Science.gov

Sample records for miniature bioreactors current

  1. Miniature bioreactors: current practices and future opportunities

    PubMed Central

    Betts, Jonathan I; Baganz, Frank

    2006-01-01

    This review focuses on the emerging field of miniature bioreactors (MBRs), and examines the way in which they are used to speed up many areas of bioprocessing. MBRs aim to achieve this acceleration as a result of their inherent high-throughput capability, which results from their ability to perform many cell cultivations in parallel. There are several applications for MBRs, ranging from media development and strain improvement to process optimisation. The potential of MBRs for use in these applications will be explained in detail in this review. MBRs are currently based on several existing bioreactor platforms such as shaken devices, stirred-tank reactors and bubble columns. This review will present the advantages and disadvantages of each design together with an appraisal of prototype and commercialised devices developed for parallel operation. Finally we will discuss how MBRs can be used in conjunction with automated robotic systems and other miniature process units to deliver a fully-integrated, high-throughput (HT) solution for cell cultivation process development. PMID:16725043

  2. Oxygen Transfer Characteristics of Miniaturized Bioreactor Systems

    PubMed Central

    Kirk, Timothy V; Szita, Nicolas

    2013-01-01

    Since their introduction in 2001 miniaturized bioreactor systems have made great advances in function and performance. In this article the dissolved oxygen (DO) transfer performance of submilliliter microbioreactors, and 1–10 mL minibioreactors was examined. Microbioreactors have reached kLa values of 460 h-1, and are offering instrumentation and some functionality comparable to production systems, but at high throughput screening volumes. Minibioreactors, aside from one 1,440 h-1 kLa system, have not offered as high rates of DO transfer, but have demonstrated superior integration with automated fluid handling systems. Microbioreactors have been typically limited to studies with E. coli, while minibioreactors have offered greater versatility in this regard. Further, mathematical relationships confirming the applicability of kLa measurements across all scales have been derived, and alternatives to fluorescence lifetime DO sensors have been evaluated. Finally, the influence on reactor performance of oxygen uptake rate (OUR), and the possibility of its real-time measurement have been explored. Biotechnol. Bioeng. 2013; 110: 1005–1019. © 2012 Wiley Periodicals, Inc. PMID:23280578

  3. Miniature Bioreactor System for Long-Term Cell Culture

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R.; Kleis, Stanley J.; Geffert, Sandara K.

    2010-01-01

    A prototype miniature bioreactor system is designed to serve as a laboratory benchtop cell-culturing system that minimizes the need for relatively expensive equipment and reagents and can be operated under computer control, thereby reducing the time and effort required of human investigators and reducing uncertainty in results. The system includes a bioreactor, a fluid-handling subsystem, a chamber wherein the bioreactor is maintained in a controlled atmosphere at a controlled temperature, and associated control subsystems. The system can be used to culture both anchorage-dependent and suspension cells, which can be either prokaryotic or eukaryotic. Cells can be cultured for extended periods of time in this system, and samples of cells can be extracted and analyzed at specified intervals. By integrating this system with one or more microanalytical instrument(s), one can construct a complete automated analytical system that can be tailored to perform one or more of a large variety of assays.

  4. High-throughput miniaturized bioreactors for cell culture process development: reproducibility, scalability, and control.

    PubMed

    Rameez, Shahid; Mostafa, Sigma S; Miller, Christopher; Shukla, Abhinav A

    2014-01-01

    Decreasing the timeframe for cell culture process development has been a key goal toward accelerating biopharmaceutical development. Advanced Microscale Bioreactors (ambr™) is an automated micro-bioreactor system with miniature single-use bioreactors with a 10-15 mL working volume controlled by an automated workstation. This system was compared to conventional bioreactor systems in terms of its performance for the production of a monoclonal antibody in a recombinant Chinese Hamster Ovary cell line. The miniaturized bioreactor system was found to produce cell culture profiles that matched across scales to 3 L, 15 L, and 200 L stirred tank bioreactors. The processes used in this article involve complex feed formulations, perturbations, and strict process control within the design space, which are in-line with processes used for commercial scale manufacturing of biopharmaceuticals. Changes to important process parameters in ambr™ resulted in predictable cell growth, viability and titer changes, which were in good agreement to data from the conventional larger scale bioreactors. ambr™ was found to successfully reproduce variations in temperature, dissolved oxygen (DO), and pH conditions similar to the larger bioreactor systems. Additionally, the miniature bioreactors were found to react well to perturbations in pH and DO through adjustments to the Proportional and Integral control loop. The data presented here demonstrates the utility of the ambr™ system as a high throughput system for cell culture process development.

  5. Presynaptic miniature GABAergic currents in developing interneurons.

    PubMed

    Trigo, Federico F; Bouhours, Brice; Rostaing, Philippe; Papageorgiou, George; Corrie, John E T; Triller, Antoine; Ogden, David; Marty, Alain

    2010-04-29

    Miniature synaptic currents have long been known to represent random transmitter release under resting conditions, but much remains to be learned about their nature and function in central synapses. In this work, we describe a new class of miniature currents ("preminis") that arise by the autocrine activation of axonal receptors following random vesicular release. Preminis are prominent in gabaergic synapses made by cerebellar interneurons during the development of the molecular layer. Unlike ordinary miniature postsynaptic currents in the same cells, premini frequencies are strongly enhanced by subthreshold depolarization, suggesting that the membrane depolarization they produce belongs to a feedback loop regulating neurotransmitter release. Thus, preminis could guide the formation of the interneuron network by enhancing neurotransmitter release at recently formed synaptic contacts.

  6. Characterization of an experimental miniature bioreactor for cellular perturbation studies.

    PubMed

    Aboka, Fredrick O; Yang, Huiling; de Jonge, Lodewijk P; Kerste, Rob; van Winden, Wouter A; van Gulik, Walter M; Hoogendijk, Rob; Oudshoorn, Arthur; Heijnen, Joseph J

    2006-12-20

    A mini bioreactor (3.0 mL volume) has been developed and shown to be a versatile tool for rapidly screening and quantifying the response of organisms on environmental perturbations. The mini bioreactor is essentially a plug flow device transformed into a well-mixed reactor by a recycle flow of the broth. The gas and liquid phases are separated by a silicone membrane. Dynamic mass transfer experiments were performed to determine the mass transfer capacities for oxygen and carbon dioxide. The mass transfer coefficients for oxygen and carbon dioxide were found to be 1.55 +/- 0.17 x 10(-5) m/s and 4.52 +/- 0.60 x 10(-6) m/s, respectively. Cultivation experiments with the 3.0 mL bioreactor show that (i) it can maintain biomass in the same physiological state as the 4.0 L lab scale bioreactor, (ii) reproducible perturbation experiments such as changing substrate uptake rate can be readily performed and the physiological response monitored quantitatively in terms of the O2 and CO2 uptake and production rates.

  7. Analysis of drug metabolism activities in a miniaturized liver cell bioreactor for use in pharmacological studies.

    PubMed

    Hoffmann, Stefan A; Müller-Vieira, Ursula; Biemel, Klaus; Knobeloch, Daniel; Heydel, Sandra; Lübberstedt, Marc; Nüssler, Andreas K; Andersson, Tommy B; Gerlach, Jörg C; Zeilinger, Katrin

    2012-12-01

    Based on a hollow fiber perfusion technology with internal oxygenation, a miniaturized bioreactor with a volume of 0.5 mL for in vitro studies was recently developed. Here, the suitability of this novel culture system for pharmacological studies was investigated, focusing on the model drug diclofenac. Primary human liver cells were cultivated in bioreactors and in conventional monolayer cultures in parallel over 10 days. From day 3 on, diclofenac was continuously applied at a therapeutic concentration (6.4 µM) for analysis of its metabolism. In addition, the activity and gene expression of the cytochrome P450 (CYP) isoforms CYP1A2, CYP2B6, CYP2C9, CYP2D6, and CYP3A4 were assessed. Diclofenac was metabolized in bioreactor cultures with an initial conversion rate of 230 ± 57 pmol/h/10(6) cells followed by a period of stable conversion of about 100 pmol/h/10(6) cells. All CYP activities tested were maintained until day 10 of bioreactor culture. The expression of corresponding mRNAs correlated well with the degree of preservation. Immunohistochemical characterization showed the formation of neo-tissue with expression of CYP2C9 and CYP3A4 and the drug transporters breast cancer resistance protein (BCRP) and multidrug resistance protein 2 (MRP2) in the bioreactor. In contrast, monolayer cultures showed a rapid decline of diclofenac conversion and cells had largely lost activity and mRNA expression of the assessed CYP isoforms at the end of the culture period. In conclusion, diclofenac metabolism, CYP activities and gene expression levels were considerably more stable in bioreactor cultures, making the novel bioreactor a useful tool for pharmacological or toxicological investigations requiring a highly physiological in vitro representation of the liver.

  8. Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues currently being cultured in rotating bioreactors by investigators

  9. Population growth and physiological characteristics of microalgae in a miniaturized bioreactor during space flight

    NASA Astrophysics Data System (ADS)

    Wang, Gaohong; Chen, Haofeng; Li, Genbao; Chen, Lanzhou; Li, Dunhai; Hu, Chunxiang; Chen, Kun; Liu, Yongding

    2006-03-01

    A strain of microalgae ( Anabaena siamensis) had been cultured in a miniaturized bioreactor during a retrievable satellite flight for 15 days. By means of remote sensing equipment installed in the satellite, we gained the growth curve of microalgae population in space every day in real time. The curve indicated that the growth of microalgae in space was slower than the control on ground. Inoculation of the retrieved microalgae culture showed that the growth rate was distinctively higher than ground control. But after several generations, both cultures indicated similar growth rates. Those data showed that algae can adapt to space environment easily which may be valuable for designing more complex bioreactor and controlled ecological life support system in future experiment.

  10. Serum-free culture of primary human hepatocytes in a miniaturized hollow-fibre membrane bioreactor for pharmacological in vitro studies.

    PubMed

    Lübberstedt, Marc; Müller-Vieira, Ursula; Biemel, Klaus M; Darnell, Malin; Hoffmann, Stefan A; Knöspel, Fanny; Wönne, Eva C; Knobeloch, Daniel; Nüssler, Andreas K; Gerlach, Jörg C; Andersson, Tommy B; Zeilinger, Katrin

    2015-09-01

    Primary human hepatocytes represent an important cell source for in vitro investigation of hepatic drug metabolism and disposition. In this study, a multi-compartment capillary membrane-based bioreactor technology for three-dimensional (3D) perfusion culture was further developed and miniaturized to a volume of less than 0.5 ml to reduce demand for cells. The miniaturized bioreactor was composed of two capillary layers, each made of alternately arranged oxygen and medium capillaries serving as a 3D culture for the cells. Metabolic activity and stability of primary human hepatocytes was studied in this bioreactor in the presence of 2.5% fetal calf serum (FCS) under serum-free conditions over a culture period of 10 days. The miniaturized bioreactor showed functions comparable to previously reported data for larger variants. Glucose and lactate metabolism, urea production, albumin synthesis and release of intracellular enzymes (AST, ALT, GLDH) showed no significant differences between serum-free and serum-supplemented bioreactors. Activities of human-relevant cytochrome P450 (CYP) isoenzymes (CYP1A2, CYP3A4/5, CYP2C9, CYP2D6, CYP2B6) analyzed by determination of product formation rates from selective probe substrates were also comparable in both groups. Gene expression analysis showed moderately higher expression in the majority of CYP enzymes, transport proteins and enzymes of Phase II metabolism in the serum-free bioreactors compared to those maintained with FCS. In conclusion, the miniaturized bioreactor maintained stable function over the investigated period and thus provides a suitable system for pharmacological studies on primary human hepatocytes under defined serum-free conditions.

  11. Fiber Attachment Module Experiment (FAME): Using a Multiplexed Miniature Hollow Fiber Membrane Bioreactor Solution for Rapid Process Testing

    NASA Astrophysics Data System (ADS)

    Lunn, Griffin; Wheeler, Raymond; Hummerick, Mary; Birmele, Michele; Richards, Jeffrey; Coutts, Janelle; Koss, Lawrence; Spencer, Lashelle.; Johnsey, Marissa; Ellis, Ronald

    Bioreactor research, even today, is mostly limited to continuous stirred-tank reactors (CSTRs). These are not an option for microgravity applications due to the lack of a gravity gradient to drive aeration as described by the Archimedes principle. This has led to testing of Hollow Fiber Membrane Bioreactors (HFMBs) for microgravity applications, including possible use for wastewater treatment systems for the International Space Station (ISS). Bioreactors and filtration systems for treating wastewater could avoid the need for harsh pretreatment chemicals and improve overall water recovery. However, the construction of these reactors is difficult and commercial off-the-shelf (COTS) versions do not exist in small sizes. We have used 1-L modular HFMBs in the past, but the need to perform rapid testing has led us to consider even smaller systems. To address this, we designed and built 125-mL, rectangular reactors, which we have called the Fiber Attachment Module Experiment (FAME) system. A polycarbonate rack of four square modules was developed with each module containing removable hollow fibers. Each FAME reactor is self-contained and can be easily plumbed with peristaltic and syringe pumps for continuous recycling of fluids and feeding, as well as fitted with sensors for monitoring pH, dissolved oxygen, and gas measurements similar to their larger counterparts. The first application tested in the FAME racks allowed analysis of over a dozen fiber surface treatments and three inoculation sources to achieve rapid reactor startup and biofilm attachment (based on carbon oxidation and nitrification of wastewater). With these miniature FAME reactors, data for this multi-factorial test were collected in duplicate over a six-month period; this greatly compressed time period required for gathering data needed to study and improve bioreactor performance.

  12. Method and Apparatus for a Miniature Bioreactor System for Long-Term Cell Culture

    NASA Technical Reports Server (NTRS)

    Kleis, Stanley J. (Inventor); Geffert, Sandra K. (Inventor); Gonda, Steve R. (Inventor)

    2015-01-01

    A bioreactor and method that permits continuous and simultaneous short, moderate, or long term cell culturing of one or more cell types or tissue in a laminar flow configuration is disclosed, where the bioreactor supports at least two laminar flow zones, which are isolated by laminar flow without the need for physical barriers between the zones. The bioreactors of this invention are ideally suited for studying short, moderate and long term studies of cell cultures and the response of cell cultures to one or more stressors such as pharmaceuticals, hypoxia, pathogens, or any other stressor. The bioreactors of this invention are also ideally suited for short, moderate or long term cell culturing with periodic cell harvesting and/or medium processing for secreted cellular components.

  13. New miniature stirred-tank bioreactors for parallel study of enzymatic biomass hydrolysis.

    PubMed

    Riedlberger, Peter; Weuster-Botz, Dirk

    2012-02-01

    Many factors strongly influence the enzymatic hydrolysis of biomass to fermentable sugars (feedstock composition, pretreatment, enzymes and enzyme loading). In order to optimize the reaction conditions for the hydrolysis of biomass, an accurate high-throughput bioprocess development tool is mandatory, which enables a parallelization and an easy scale-up. New S-shaped impellers were developed for magnetically inductive driven stirred-tank bioreactors at a 10mL-scale. An efficient and reproducible homogenization was shown at 20% w/w solids loading of microcrystalline cellulose and at, 4-10% with wheat straw in 48 parallel operated stirred-tank bioreactors. The scale-up was successfully validated for the enzymatic hydrolysis of wheat straw suspensions and microcrystalline cellulose mixtures by application of a cellulase complex at a milliliter- and liter-scale. As an example, the parallel stirred-tank bioreactor system was applied for the evaluation of enzymatic batch hydrolyses of plant materials with varying pretreatments.

  14. Miniaturized auto-focusing VCM actuator with zero holding current.

    PubMed

    Liu, Chien-Sheng; Lin, Psang Dain

    2009-06-01

    In keeping with consumers' preferences for electronic products of ever smaller size and enhanced functionality, it is necessary to reduce the profile of the auto-focusing actuators used in camera phones without sacrificing their performance. Accordingly, this study modifies the Voice Coil Motor (VCM) actuator proposed by the current group in a previous study (C. S. Liu and P. D. Lin, Opt. Express, 16, 2533-2540, 2008) to accomplish a miniaturized auto-focusing actuator for cell phone camera modules with minimal power consumption. The proposed device comprises a VCM, a closed-loop position control system, a magnetoconductive plate, and a lens support structure to drive the lens to the optimal focusing position. The experimental results show that the actuator has a zero holding current when maintaining the lens in the specified focusing position. Overall, it is shown that compared to existing VCM actuators, the proposed actuator has bo a higher power efficiency and an improved positioning repeatability.

  15. Miniaturized auto-focusing VCM actuator with zero holding current.

    PubMed

    Liu, Chien-Sheng; Lin, Psang Dain

    2009-06-01

    In keeping with consumers' preferences for electronic products of ever smaller size and enhanced functionality, it is necessary to reduce the profile of the auto-focusing actuators used in camera phones without sacrificing their performance. Accordingly, this study modifies the Voice Coil Motor (VCM) actuator proposed by the current group in a previous study (C. S. Liu and P. D. Lin, Opt. Express, 16, 2533-2540, 2008) to accomplish a miniaturized auto-focusing actuator for cell phone camera modules with minimal power consumption. The proposed device comprises a VCM, a closed-loop position control system, a magnetoconductive plate, and a lens support structure to drive the lens to the optimal focusing position. The experimental results show that the actuator has a zero holding current when maintaining the lens in the specified focusing position. Overall, it is shown that compared to existing VCM actuators, the proposed actuator has bo a higher power efficiency and an improved positioning repeatability. PMID:19506625

  16. Fiber Attachment Module Experiment (FAME): Using a Multiplexed Miniature Hollow Fiber Membrane Bioreactor Solution for Rapid Process Testing

    NASA Technical Reports Server (NTRS)

    Coutts, Janelle L.; Lunn, Griffin M.; Koss, Lawrence L.; Hummerick, Mary E.; Spencer, Lachelle E.; Johnsey, Marissa N.; Richards, Jeffrey T.; Ellis, Ronald; Birmele, Michele N.; Wheeler, Raymond M.

    2014-01-01

    Bioreactor research is mostly limited to continuous stirred-tank reactors (CSTRs) which are not an option for microgravity (g) applications due to the lack of a gravity gradient to drive aeration as described by the Archimedes principle. Bioreactors and filtration systems for treating wastewater in g could avoid the need for harsh pretreatment chemicals and improve overall water recovery. Solution: Membrane Aerated Bioreactors (MABRs) for g applications, including possible use for wastewater treatment systems for the International Space Station (ISS).

  17. Characterization of oxygen transfer in miniature and lab-scale bubble column bioreactors and comparison of microbial growth performance based on constant k(L)a.

    PubMed

    Doig, Steven D; Ortiz-Ochoa, Kenny; Ward, John M; Baganz, Frank

    2005-01-01

    This work describes the engineering characterization of miniature (2 mL) and laboratory-scale (100 mL) bubble column bioreactors useful for the cultivation of microbial cells. These bioreactors were constructed of glass and used a range of sintered glass gas diffusers with differently sized pores to disperse humidified air within the liquid biomedium. The effect of the pressure of this supplied air on the breakthrough point for gas diffusers with different pore sizes was examined and could be predicted using the Laplace-Young equation. The influence of the superficial gas velocity (u(g)) on the volumetric mass transfer coefficient (k(L)a) was determined, and values of up to 0.09 s(-1) were observed in this work. Two modeling approaches were considered in order to predict and provide comparison criteria. The first related the volumetric power consumption (P/V) to the k(L)a and a good correlation was obtained for differently sized reactors with a given pore size, but this correlation was not satisfactory for bubble columns with different gas diffusers. Values for P/V ranged from about 10 to 400 W.m(-3). Second, a model was developed predicting bubble size (d(b)), bubble rising velocity (u(b)), gas hold-up (phi), liquid side mass transfer coefficient (k(L)), and thus the k(L)a using established theory and empirical correlations. Good agreement was found with our experimental data at different scales and pore sizes. Values for d(b) varied from 0.1 to 0.6 mm, and k(L) values between 1.7 and 9.8 x 10(-4) m.s(-1) were determined. Several E. coli cultivations were performed in the miniature bubble column at low and high k(L)a values, and the results were compared to those from a conventional stirred tank operated under identical k(L)a values. Results from the two systems were similar in terms of biomass growth rate and carbon source utilization.

  18. In Vivo Demonstration of Addressable Microstimulators Powered by Rectification of Epidermically Applied Currents for Miniaturized Neuroprostheses.

    PubMed

    Becerra-Fajardo, Laura; Ivorra, Antoni

    2015-01-01

    Electrical stimulation is used in order to restore nerve mediated functions in patients with neurological disorders, but its applicability is constrained by the invasiveness of the systems required to perform it. As an alternative to implantable systems consisting of central stimulation units wired to the stimulation electrodes, networks of wireless microstimulators have been devised for fine movement restoration. Miniaturization of these microstimulators is currently hampered by the available methods for powering them. Previously, we have proposed and demonstrated a heterodox electrical stimulation method based on electronic rectification of high frequency current bursts. These bursts can be delivered through textile electrodes on the skin. This approach has the potential to result in an unprecedented level of miniaturization as no bulky parts such as coils or batteries are included in the implant. We envision microstimulators designs based on application-specific integrated circuits (ASICs) that will be flexible, thread-like (diameters < 0.5 mm) and not only with controlled stimulation capabilities but also with sensing capabilities for artificial proprioception. We in vivo demonstrate that neuroprostheses composed of addressable microstimulators based on this electrical stimulation method are feasible and can perform controlled charge-balanced electrical stimulation of muscles. We developed miniature external circuit prototypes connected to two bipolar probes that were percutaneously implanted in agonist and antagonist muscles of the hindlimb of an anesthetized rabbit. The electronic implant architecture was able to decode commands that were amplitude modulated on the high frequency (1 MHz) auxiliary current bursts. The devices were capable of independently stimulating the target tissues, accomplishing controlled dorsiflexion and plantarflexion joint movements. In addition, we numerically show that the high frequency current bursts comply with safety standards

  19. In Vivo Demonstration of Addressable Microstimulators Powered by Rectification of Epidermically Applied Currents for Miniaturized Neuroprostheses

    PubMed Central

    2015-01-01

    Electrical stimulation is used in order to restore nerve mediated functions in patients with neurological disorders, but its applicability is constrained by the invasiveness of the systems required to perform it. As an alternative to implantable systems consisting of central stimulation units wired to the stimulation electrodes, networks of wireless microstimulators have been devised for fine movement restoration. Miniaturization of these microstimulators is currently hampered by the available methods for powering them. Previously, we have proposed and demonstrated a heterodox electrical stimulation method based on electronic rectification of high frequency current bursts. These bursts can be delivered through textile electrodes on the skin. This approach has the potential to result in an unprecedented level of miniaturization as no bulky parts such as coils or batteries are included in the implant. We envision microstimulators designs based on application-specific integrated circuits (ASICs) that will be flexible, thread-like (diameters < 0.5 mm) and not only with controlled stimulation capabilities but also with sensing capabilities for artificial proprioception. We in vivo demonstrate that neuroprostheses composed of addressable microstimulators based on this electrical stimulation method are feasible and can perform controlled charge-balanced electrical stimulation of muscles. We developed miniature external circuit prototypes connected to two bipolar probes that were percutaneously implanted in agonist and antagonist muscles of the hindlimb of an anesthetized rabbit. The electronic implant architecture was able to decode commands that were amplitude modulated on the high frequency (1 MHz) auxiliary current bursts. The devices were capable of independently stimulating the target tissues, accomplishing controlled dorsiflexion and plantarflexion joint movements. In addition, we numerically show that the high frequency current bursts comply with safety standards

  20. Effects of Ketamine on Neuronal Spontaneous Excitatory Postsynaptic Currents and Miniature Excitatory Postsynaptic Currents in the Somatosensory Cortex of Rats

    PubMed Central

    Yuan, Chengdong; Zhang, Yajun; Zhang, Yu; Cao, Song; Wang, Yuan; Fu, Bao; Yu, Tian

    2016-01-01

    Background: Ketamine is a commonly used intravenous anesthetic which produces dissociation anesthesia, analgesia, and amnesia. The mechanism of ketamine-induced synaptic inhibition in high-level cortical areas is still unknown. We aimed to elucidate the effects of different concentrations of ketamine on the glutamatergic synaptic transmission of the neurons in the primary somatosensory cortex by using the whole-cell patch-clamp method. Methods: Sprague-Dawley rats (11–19 postnatal days, n=36) were used to obtain brain slices (300 μM). Spontaneous excitatory postsynaptic currents (data from 40 neurons) were recorded at a command potential of -70 mV in the presence of bicuculline (a competitive antagonist of GABAA receptors, 30 μM) and strychnine (glycine receptor antagonist, 30 μM). Miniature excitatory postsynaptic currents (data from 40 neurons) were also recorded when 1 μM of tetrodotoxin was added into the artificial cerebrospinal fluid. We used GraphPad Prism5for statistical analysis. Significant differences in the mean amplitude and frequency were tested using the Student paired 2-tailed t test. Values of P<0.05 were considered significant. Results: Different concentrations of ketamine inhibited the frequency and amplitude of the spontaneous excitatory postsynaptic currents as well as the amplitude of the miniature excitatory postsynaptic currents in a concentration-dependent manner, but they exerted no significant effect on the frequency of the miniature excitatory postsynaptic currents. Conclusion: Ketamine inhibited the excitatory synaptic transmission of the neurons in the primary somatosensory cortex. The inhibition may have been mediated by a reduction in the sensitivity of the postsynaptic glutamatergic receptors. PMID:27365548

  1. Miniature excitatory synaptic ion currents in the earthworm Lumbricus terrestris body wall muscles.

    PubMed

    Volkov, E M; Nurullin, L F; Nikolsky, E; Vyskocil, F

    2007-01-01

    The miniature excitatory postsynaptic currents (MEPCs) of the muscle cells of the earthworm Lumbricus terrestris were recorded by glass microelectrodes. In a single synaptic zone, three types of MEPC were recorded: a fast single-exponential type that decayed with tau =0.9 ms, a slow single-exponential with tau = 9.2 ms and a two-exponential MEPC with tau = 1.3 and 8.5 ms, respectively. The muscle cells of earthworms contain populations of yet-unidentified ionic channels that might be different from the common nicotinic and muscarinic groups of acetylcholine receptors, since these MEPCs are not sensitive to d-tubocurarine, atropine, benzohexonium or proserine. Alternatively, besides ACh receptors, the membrane may contain receptors for another yet-unidentified excitatory transmitter. PMID:17973597

  2. Effect of adrenalectomy on miniature inhibitory postsynaptic currents in the paraventricular nucleus of the hypothalamus.

    PubMed

    Verkuyl, J M; Joëls, M

    2003-01-01

    Within the rat paraventricular nucleus of the hypothalamus two types of neurons have been distinguished based on morphological appearance, i.e., parvocellular and magnocellular neurons. The parvocellular neurons play a key role in regulating the activity of the hypothalamo-pituitary-adrenal axis, which is activated, e.g., after stress exposure. These neurons receive humoral negative feedback via the adrenal hormone corticosterone but also neuronal inhibitory input, either directly or transsynaptically relayed via GABAergic interneurons. In the present study we examined to what extent the neuronal GABAergic input is influenced by the humoral signal. To this end, miniature inhibitory postsynaptic currents (mIPSCs) were recorded in parvo- and magnocellular neurons of adrenalectomized rats, which lack corticosterone, and in sham-operated controls. Under visual control neurons in coronal slices containing the paraventricular nucleus were designated as putative parvocellular or magnocellular neurons: the former were located in the medial part of the nucleus and displayed a small fusiform soma; the latter were mostly located in the lateral part and were recognized by their large round soma. Compared with putative magnocellular neurons, parvocellular neurons generally exhibited a lower membrane capacitance, lower mIPSC frequency, and smaller mIPSC amplitude. Following adrenalectomy, the mIPSC frequency was significantly enhanced in parvo- but not magnocellular neurons. Other properties of the cells were not affected. In a second series of experiments we examined whether the increase in mIPSC frequency was due to the absence of corticosterone or caused by other effects related to adrenalectomy. The data support the former explanation since implantation of a corticosterone releasing pellet after adrenalectomy fully prevented the change in mIPSC frequency. We conclude that, in the absence of humoral negative feedback, local GABAergic input of parvocellular neurons in the

  3. A system of miniaturized stirred bioreactors for parallel continuous cultivation of yeast with online measurement of dissolved oxygen and off-gas.

    PubMed

    Klein, Tobias; Schneider, Konstantin; Heinzle, Elmar

    2013-02-01

    Chemostat cultivation is a powerful tool for physiological studies of microorganisms. We report the construction and application of a set of eight parallel small-scale bioreactors with a working volume of 10 mL for continuous cultivation. Hungate tubes were used as culture vessels connected to multichannel-peristaltic pumps for feeding fresh media and removal of culture broth and off-gas. Water saturated air is sucked into the bioreactors by applying negative pressure, and small stirrer bars inside the culture vessels allow sufficient mixing and oxygen transfer. Optical sensors are used for non-invasive online measurement of dissolved oxygen, which proved to be a powerful indicator of the physiological state of the cultures, particularly of steady-state conditions. Analysis of culture exhaust-gas by means of mass spectrometry enables balancing of carbon. The capacity of the developed small-scale bioreactor system was validated using the fission yeast Schizosaccharomyces pombe, focusing on the metabolic shift from respiratory to respiro-fermentative metabolism, as well as studies on consumption of different substrates such as glucose, fructose, and gluconate. In all cases, an almost completely closed carbon balance was obtained proving the reliability of the experimental setup.

  4. A miniature high voltage plasma interaction flight experiment - Project MINX. [for measuring solar cell array parasitic current drain

    NASA Technical Reports Server (NTRS)

    Riley, T. J.; Triner, J. E.; Sater, B. L.; Cohen, D.; Somberg, H.

    1974-01-01

    A miniature high-voltage array was fabricated, incorporating the multi-junction edge illuminated (MJC) cell technique. The array consists of 32 2x2.2 cm MJCs, series connected, capable of 1600 V open circuit at 1 AMO and 1.2 mA short circuit. A solid state, high-voltage relay is connected across each 4-cell subgroup of the array. It was built to test plasma current drain on space systems using high voltage as might occur when a high-voltage solar array is operated from low to synchronous orbit.

  5. PRACTICE REVIEW OF FIVE BIOREACTOR/RECIRCULATION LANDFILLS

    EPA Science Inventory

    Six bioreactor landfills were analyzed to provide a perspective of current practice and technical issues that differentiate bioreactor landfills from conventional landfills. Five of the bioreactor landfills were anaerobic and one was aerated. In one case, nearly identical cells e...

  6. Monte Carlo simulation of miniature endplate current generation in the vertebrate neuromuscular junction.

    PubMed Central

    Bartol, T M; Land, B R; Salpeter, E E; Salpeter, M M

    1991-01-01

    A Monte Carlo method for modeling the neuromuscular junction is described in which the three-dimensional structure of the synapse can be specified. Complexities can be introduced into the acetylcholine kinetic model used with only a small increase in computing time. The Monte Carlo technique is shown to be superior to differential equation modeling methods (although less accurate) if a three-dimensional representation of synaptic geometry is desired. The conceptual development of the model is presented and the accuracy estimated. The consequences of manipulations such as varying the spacing of secondary synaptic folds or that between the release of multiple quantal packets of acetylcholine, are also presented. Increasing the spacing between folds increases peak current. Decreased spacing of adjacent quantal release sites increases the potentiation of peak current. Images FIGURE 1 FIGURE 1 FIGURE 7 FIGURE 8 FIGURE 10 FIGURE 11 PMID:1873466

  7. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Laptop computer sits atop the Experiment Control Computer for a NASA Bioreactor. The flight crew can change operating conditions in the Bioreactor by using the graphical interface on the laptop. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  8. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Close-up view of the interior of a NASA Bioreactor shows the plastic plumbing and valves (cylinders at center) to control fluid flow. A fresh nutrient bag is installed at top; a flattened waste bag behind it will fill as the nutrients are consumed during the course of operation. The drive chain and gears for the rotating wall vessel are visible at bottom center center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  9. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Interior view of the gas supply for the NASA Bioreactor. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  10. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  11. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Exterior view of the NASA Bioreactor Engineering Development Unit flown on Mir. The rotating wall vessel is behind the window on the face of the large module. Control electronics are in the module at left; gas supply and cooling fans are in the module at back. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  12. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Electronics control module for the NASA Bioreactor. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  13. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Interior of a Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  14. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell and with thermal blankets partially removed. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  15. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Close-up view of the interior of a NASA Bioreactor shows the plastic plumbing and valves (cylinders at right center) to control fluid flow. The rotating wall vessel is at top center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  16. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Biotechnology Refrigerator (BTR) holds fixed tissue culture bags at 4 degrees C to preserve them for return to Earth and postflight analysis. The cultures are used in research with the NASA Bioreactor cell science program. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  17. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The heart of the bioreactor is the rotating wall vessel, shown without its support equipment. Volume is about 125 mL. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  18. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Astronaut John Blaha replaces an exhausted media bag and filled waste bag with fresh bags to continue a bioreactor experiment aboard space station Mir in 1996. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. This image is from a video downlink. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  19. The Whole new world of miniature technology

    SciTech Connect

    Gillespie, L.K.

    1980-07-01

    In the past ten years, miniaturization of both electrical and mechanical parts has significantly increased. Documentation of the design and production capabilities of miniaturization in the electronics industry is well-defined. Literature on the subject of miniaturization of metal piece parts, however, is hard to find. Some of the current capabilities in the manufacture of miniature metal piece parts or miniature features in larger piece parts are discussed.

  20. Bioreactor principles

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Cells cultured on Earth (left) typically settle quickly on the bottom of culture vessels due to gravity. In microgravity (right), cells remain suspended and aggregate to form three-dimensional tissue. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  1. Bioreactors and bioseparation.

    PubMed

    Zhang, Siliang; Cao, Xuejun; Chu, Ju; Qian, Jiangchao; Zhuang, Yingping

    2010-01-01

    Along with the rapid development of life science, great attention has been increasingly given to the biotechnological products of cell cultivation technology. In the course of industrialization, bioreactor and bioproduct separation techniques are the two essential technical platforms. In this chapter, the current situation and development prospects of bioreactor techniques in China are systematically discussed, starting with the elucidation of bioreactor processes and the principle of process optimization. Separation technology for biological products is also briefly introduced.At present, a series of bioreactors made by Chinese enterprises have been widely used for laboratory microbial cultivation, process optimization studies, and large-scale production. In the course of bioprocess optimization studies, the complicated bioprocesses in a bioreactor could be resolved into different reaction processes on three scales, namely genetic, cellular, and bioreactor scales. The structural varieties and nonlinear features of various scales of bioprocess systems was discussed through considering the mutual effects of different scale events, namely material flux, energy flux, and information flux, and the optimization approach for bioprocesses was proposed by taking the analysis of metabolic flux and multiscale consideration as a core strategy.In order to realize such an optimization approach, a bioreactor system based on association analysis of multiscale parameters was elaborated, and process optimization of many biological products were materialized, which resulted in great improvement in production efficiency. In designing and manufacturing large-scale bioreactors, the principle of scaling up a process incorporated with flow field study and physiological features in a bioreactor was suggested according to the criterion for the scale-up of cellular physiological and metabolic traits. The flow field features of a bioreactor were investigated through computational fluid

  2. Bioreactors and bioseparation.

    PubMed

    Zhang, Siliang; Cao, Xuejun; Chu, Ju; Qian, Jiangchao; Zhuang, Yingping

    2010-01-01

    Along with the rapid development of life science, great attention has been increasingly given to the biotechnological products of cell cultivation technology. In the course of industrialization, bioreactor and bioproduct separation techniques are the two essential technical platforms. In this chapter, the current situation and development prospects of bioreactor techniques in China are systematically discussed, starting with the elucidation of bioreactor processes and the principle of process optimization. Separation technology for biological products is also briefly introduced.At present, a series of bioreactors made by Chinese enterprises have been widely used for laboratory microbial cultivation, process optimization studies, and large-scale production. In the course of bioprocess optimization studies, the complicated bioprocesses in a bioreactor could be resolved into different reaction processes on three scales, namely genetic, cellular, and bioreactor scales. The structural varieties and nonlinear features of various scales of bioprocess systems was discussed through considering the mutual effects of different scale events, namely material flux, energy flux, and information flux, and the optimization approach for bioprocesses was proposed by taking the analysis of metabolic flux and multiscale consideration as a core strategy.In order to realize such an optimization approach, a bioreactor system based on association analysis of multiscale parameters was elaborated, and process optimization of many biological products were materialized, which resulted in great improvement in production efficiency. In designing and manufacturing large-scale bioreactors, the principle of scaling up a process incorporated with flow field study and physiological features in a bioreactor was suggested according to the criterion for the scale-up of cellular physiological and metabolic traits. The flow field features of a bioreactor were investigated through computational fluid

  3. Measurements of miniature ionization chamber currents in the JSI TRIGA Mark II reactor demonstrate the importance of the delayed contribution to the photon field in nuclear reactors

    NASA Astrophysics Data System (ADS)

    Radulović, Vladimir; Fourmentel, Damien; Barbot, Loïc; Villard, Jean-François; Kaiba, Tanja; Gašper, Žerovnik; Snoj, Luka

    2015-12-01

    The characterization of experimental locations of a research nuclear reactor implies the determination of neutron and photon flux levels within, with the best achievable accuracy. In nuclear reactors, photon fluxes are commonly calculated by Monte Carlo simulations but rarely measured on-line. In this context, experiments were conducted with a miniature gas ionization chamber (MIC) based on miniature fission chamber mechanical parts, recently developed by the CEA (French Atomic Energy and Alternative Energies Commission) irradiated in the core of the Jožef Stefan Institute TRIGA Mark II reactor in Ljubljana, Slovenia. The aim of the study was to compare the measured MIC currents with calculated currents based on simulations with the MCNP6 code. A discrepancy of around 50% was observed between the measured and the calculated currents; in the latter taking into consideration only the prompt photon field. Further experimental measurements of MIC currents following reactor SCRAMs (reactor shutdown with rapid insertions of control rods) provide evidence that over 30% of the total measured signal is due to the delayed photon field, originating from fission and activation products, which are untreated in the calculations. In the comparison between the measured and calculated values, these findings imply an overall discrepancy of less than 20% of the total signal which is still unexplained.

  4. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 deg. C (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  5. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101824 for a version with labels, and No. 0103180 for an operational schematic.

  6. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101816 for a version without labels, and No. 0103180 for an operational schematic.

  7. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101823 for a version without labels, and No. 0103180 for an operational schematic.

  8. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101825 for a version with major elements labeled, and No. 0103180 for an operational schematic. 0101816

  9. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 degreesC (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  10. Multimembrane Bioreactor

    NASA Technical Reports Server (NTRS)

    Cho, Toohyon; Shuler, Michael L.

    1989-01-01

    Set of hydrophilic and hydrophobic membranes in bioreactor allows product of reaction to be separated, while nutrients fed to reacting cells and byproducts removed from them. Separation process requires no externally supplied energy; free energy of reaction sufficient. Membranes greatly increase productivity of metabolizing cells by continuously removing product and byproducts, which might otherwise inhibit reaction, and by continuously adding oxygen and organic nutrients.

  11. Development of a Space Bioreactor using Microtechnology

    NASA Technical Reports Server (NTRS)

    Arquint, Philippe; Boillat, Marc A.; deRooij, Nico F.; Jeanneret, Sylvain; vanderSchoot, Bart H.; Bechler, Birgitt; Cogoli, Augusto; Walther, Isabelle; Gass, Volker; Ivorra, Marie-Therese

    1995-01-01

    A miniature bio-reactor for the cultivation of cells aboard Spacelab is presented. Yeast cells are grown in a 3 milliliter reactor chamber. A supply of fresh nutrient medium is provided by a piezo-electric silicon micro-pump. In the reactor, pH, temperature, and redox potential are monitored and the pH is regulated at a constant value. The complete instrument is fitted in a standard experiment container of 63 x 63 x 85 mm. The bioreactor was used on the IML-2 mission in July 1994 and is being refurbished for a reflight in the spring of 1996.

  12. Miniature Earthmover

    NASA Technical Reports Server (NTRS)

    1996-01-01

    International Machinery Corporation (IMC) developed a miniature earthmover, the 1/8 scale Caterpillar D11N Track-type Tractor, with trademark product approval and manufacturing/marketing license from Caterpillar, Inc. Through Marshall Space Flight Center assistance, the company has acquired infrared remote control technology, originally developed for space exploration. The technology is necessary for exports because of varying restrictions on radio frequency in foreign countries. The Cat D11N weighs only 340 pounds and has the world's first miniature industrial internal combustion engine. The earthmover's uses include mining, construction and demolition work, and hazardous environment work. IMC also has designs of various products for military use and other Caterpillar replicas.

  13. A nanoliter microfluidic serial dilution bioreactor.

    PubMed

    Gu, Guo-Yue; Lee, Yi-Wei; Chiang, Chih-Chung; Yang, Ya-Tang

    2015-07-01

    Bacterial culture is a basic technique in both fundamental and applied microbiology. The excessive reagent consumption and laborious maintenance of bulk bioreactors for microbial culture have prompted the development of miniaturized on-chip bioreactors. With the minimal choice of two compartments (N = 2) and discrete time, periodic dilution steps, we realize a microfluidic bioreactor that mimics macroscopic serial dilution transfer culture. This device supports automated, long-term microbial cultures with a nanoliter-scale working volume and real-time monitoring of microbial populations at single-cell resolution. Because of the high surface-to-volume ratio, the device also operates as an effective biofilm-flow reactor to support cogrowth of planktonic and biofilm populations. We expect that such devices will open opportunities in many fields of microbiology.

  14. Bioreactors Addressing Diabetes Mellitus

    PubMed Central

    Minteer, Danielle M.; Gerlach, Jorg C.

    2014-01-01

    The concept of bioreactors in biochemical engineering is a well-established process; however, the idea of applying bioreactor technology to biomedical and tissue engineering issues is relatively novel and has been rapidly accepted as a culture model. Tissue engineers have developed and adapted various types of bioreactors in which to culture many different cell types and therapies addressing several diseases, including diabetes mellitus types 1 and 2. With a rising world of bioreactor development and an ever increasing diagnosis rate of diabetes, this review aims to highlight bioreactor history and emerging bioreactor technologies used for diabetes-related cell culture and therapies. PMID:25160666

  15. Bioreactors addressing diabetes mellitus.

    PubMed

    Minteer, Danielle M; Gerlach, Jorg C; Marra, Kacey G

    2014-11-01

    The concept of bioreactors in biochemical engineering is a well-established process; however, the idea of applying bioreactor technology to biomedical and tissue engineering issues is relatively novel and has been rapidly accepted as a culture model. Tissue engineers have developed and adapted various types of bioreactors in which to culture many different cell types and therapies addressing several diseases, including diabetes mellitus types 1 and 2. With a rising world of bioreactor development and an ever increasing diagnosis rate of diabetes, this review aims to highlight bioreactor history and emerging bioreactor technologies used for diabetes-related cell culture and therapies.

  16. Miniature electrical connector

    DOEpatents

    Casper, Robert F.

    1976-01-01

    A miniature coaxial cable electrical connector includes an annular compressible gasket in a receptacle member, the gasket having a generally triangular cross section resiliently engaging and encircling a conically tapered outer surface of a plug member to create an elongated current leakage path at their interface; means for preventing rotation of the plug relative to the receptacle; a metal sleeve forming a portion of the receptacle and encircling the plug member when interconnected; and a split ring in the plug having outwardly and rearwardly projecting fingers spaced from and encircling a portion of a coaxial cable and engageable with the metal sleeve to interlock the receptacle and plug.

  17. Bio-reactor chamber

    NASA Technical Reports Server (NTRS)

    Chandler, Joseph A. (Inventor)

    1989-01-01

    A bioreactor for cell culture is disclosed which provides for the introduction of fresh medium without excessive turbulent action. The fresh medium enters the bioreactor through a filter with a backwash action which prevents the cells from settling on the filter. The bioreactor is sealed and depleted medium is forced out of the container as fresh medium is added.

  18. Advances in Miniaturized Instruments for Genomics

    PubMed Central

    2014-01-01

    In recent years, a lot of demonstrations of the miniaturized instruments were reported for genomic applications. They provided the advantages of miniaturization, automation, sensitivity, and specificity for the development of point-of-care diagnostics. The aim of this paper is to report on recent developments on miniaturized instruments for genomic applications. Based on the mature development of microfabrication, microfluidic systems have been demonstrated for various genomic detections. Since one of the objectives of miniaturized instruments is for the development of point-of-care device, impedimetric detection is found to be a promising technique for this purpose. An in-depth discussion of the impedimetric circuits and systems will be included to provide total consideration of the miniaturized instruments and their potential application towards real-time portable imaging in the “-omics” era. The current excellent demonstrations suggest a solid foundation for the development of practical and widespread point-of-care genomic diagnostic devices. PMID:25114919

  19. In vivo bioreactors for mandibular reconstruction.

    PubMed

    Tatara, A M; Wong, M E; Mikos, A G

    2014-12-01

    Large mandibular defects are difficult to reconstruct with good functional and aesthetic outcomes because of the complex geometry of craniofacial bone. While the current gold standard is free tissue flap transfer, this treatment is limited in fidelity by the shape of the harvested tissue and can result in significant donor site morbidity. To address these problems, in vivo bioreactors have been explored as an approach to generate autologous prefabricated tissue flaps. These bioreactors are implanted in an ectopic site in the body, where ossified tissue grows into the bioreactor in predefined geometries and local vessels are recruited to vascularize the developing construct. The prefabricated flap can then be harvested with vessels and transferred to a mandibular defect for optimal reconstruction. The objective of this review article is to introduce the concept of the in vivo bioreactor, describe important preclinical models in the field, summarize the human cases that have been reported through this strategy, and offer future directions for this exciting approach.

  20. Bioreactors for tissue engineering.

    PubMed

    Chen, Huang-Chi; Hu, Yu-Chen

    2006-09-01

    Bioreactors are essential in tissue engineering, not only because they provide an in vitro environment mimicking in vivo conditions for the growth of tissue substitutes, but also because they enable systematic studies of the responses of living tissues to various mechanical and biochemical cues. The basic principles of bioreactor design are reviewed, the bioreactors commonly used for the tissue engineering of cartilage, bone and cardiovascular systems are assessed in terms of their performance and usefulness. Several novel bioreactor types are also reviewed. PMID:16955350

  1. NASA Bioreactor Demonstration System

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Leland W. K. Chung (left), Director, Molecular Urology Therapeutics Program at the Winship Cancer Institute at Emory University, is principal investigator for the NASA bioreactor demonstration system (BDS-05). With him is Dr. Jun Shu, an assistant professor of Orthopedics Surgery from Kuming Medical University China. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  2. LEACHATE NITROGEN CONCENTRATIONS AND BACTERIAL NUMBERS FROM TWO BIOREACTOR LANDFILLS

    EPA Science Inventory

    The U.S. EPA and Waste Management Inc. have entered into a cooperative research and development agreement (CRADA) to study landfills operated as bioreactors. Two different landfill bioreactor configurations are currently being tested at the Outer Loop landfill in Louisville, KY...

  3. Miniature Radioisotope Power Source

    NASA Technical Reports Server (NTRS)

    Chmielewski, Artur B.

    1995-01-01

    Proposed miniature power source generates electricity for years from heat developed in small radioisotope unit without addition of fuel or dependence on sunlight. Called powerstick, is relatively inexpensive, lightweight, and rugged. Supplies power to small vehicles or scientific instruments in remote locations on Earth or in outer space. Envisioned uses include Mars miniature rovers and monitoring equipment for toxic or nuclear storage sites.

  4. Bioreactor rotating wall vessel

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells.

  5. Configuration of bioreactors.

    PubMed

    Martens, Dirk E; van den End, Evert J; Streefland, Mathieu

    2014-01-01

    Lab-scale stirred-tank bioreactors (0.2-20 l) are used for fundamental research on animal cells and in process development and troubleshooting for large-scale production. In this chapter, different configurations of bioreactor systems are shortly discussed and setting up these different configurations is described. In addition, online measurement and control of bioreactor parameters is described, with special attention to controller settings (PID) and online measurement of oxygen consumption and carbon dioxide production. Finally, methods for determining the oxygen transfer coefficient are described.

  6. Bioreactors: design and operation

    SciTech Connect

    Cooney, C.L.

    1983-02-11

    The bioreactor provides a central link between the starting feedstock and the product. The reaction yield and selectivity are determined by the biocatalyst, but productivity is often determined by the process technology; as a consequence, biochemical reaction engineering becomes the interface for the biologist and engineer. Developments in bioreactor design, including whole cell immobilization, immobilized enzymes, continuous reaction, and process control, will increasingly reflect the need for cross-disciplinary interaction in the biochemical process industry. This paper examines the strategy for selection and design of bioreactors and identifies the limits and constraints in their use. 25 references, 3 figures, 3 tables.

  7. Space Bioreactor Science Workshop

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Editor)

    1987-01-01

    The first space bioreactor has been designed for microprocessor control, no gaseous headspace, circulation and resupply of culture medium, and a slow mixing in very low shear regimes. Various ground based bioreactors are being used to test reactor vessel design, on-line sensors, effects of shear, nutrient supply, and waste removal from continuous culture of human cells attached to microcarriers. The small (500 ml) bioreactor is being constructed for flight experiments in the Shuttle middeck to verify systems operation under microgravity conditions and to measure the efficiencies of mass transport, gas transfer, oxygen consumption, and control of low shear stress on cells. Applications of microcarrier cultures, development of the first space bioreactor flight system, shear and mixing effects on cells, process control, and methods to monitor cell metabolism and nutrient requirements are among the topics covered.

  8. Bioreactor design concepts

    NASA Technical Reports Server (NTRS)

    Bowie, William

    1987-01-01

    Two parallel lines of work are underway in the bioreactor laboratory. One of the efforts is devoted to the continued development and utilization of a laboratory research system. That system's design is intended to be fluid and dynamic. The sole purpose of such a device is to allow testing and development of equipment concepts and procedures. Some of the results of those processes are discussed. A second effort is designed to produce a flight-like bioreactor contained in a double middeck locker. The result of that effort has been to freeze a particular bioreactor design in order to allow fabrication of the custom parts. The system is expected to be ready for flight in early 1988. However, continued use of the laboratory system will lead to improvements in the space bioreactor. Those improvements can only be integrated after the initial flight series.

  9. Tapered bed bioreactor

    DOEpatents

    Scott, Charles D.; Hancher, Charles W.

    1977-01-01

    A vertically oriented conically shaped column is used as a fluidized bed bioreactor wherein biologically catalyzed reactions are conducted in a continuous manner. The column utilizes a packing material a support having attached thereto a biologically active catalytic material.

  10. BIOREACTOR LANDFILL DESIGN

    EPA Science Inventory

    Modern landfill design entails many elements including foundations, liner systems, leachate collection systems, stormwater control systems, slope stability considerations, leachate management systems, gas extraction systems, and capping and closure. The use of bioreactor technolo...

  11. Miniature TV Camera

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Originally devised to observe Saturn stage separation during Apollo flights, Marshall Space Flight Center's Miniature Television Camera, measuring only 4 x 3 x 1 1/2 inches, quickly made its way to the commercial telecommunications market.

  12. NASA Classroom Bioreactor

    NASA Technical Reports Server (NTRS)

    Scully, Robert

    2004-01-01

    Exploration of space provides a compelling need for cell-based research into the basic mechanisms that underlie the profound changes that occur in terrestrial life that is transitioned to low gravity environments. Toward that end, NASA developed a rotating bioreactor in which cells are cultured while continuously suspended in a cylinder in which the culture medium rotates with the cylinder. The randomization of the gravity vector accomplished by the continuous rotation, in a low shear environment, provides an analog of microgravity. Because cultures grown in bioreactors develop structures and functions that are much closer to those exhibited by native tissue than can be achieved with traditional culture methods, bioreactors have contributed substantially to advancing research in the fields of cancer, diabetes, infectious disease modeling for vaccine production, drug efficacy, and tissue engineering. NASA has developed a Classroom Bioreactor (CB) that is built from parts that are easily obtained and assembled, user-friendly and versatile. It can be easily used in simple school settings to examine the effect cultures of seeds or cells. An educational brief provides assembly instructions and lesson plans that describes activities in science, math and technology that explore free fall, microgravity, orbits, bioreactors, structure-function relationships and the scientific method.

  13. NASA Bioreactor Schematic

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The schematic depicts the major elements and flow patterns inside the NASA Bioreactor system. Waste and fresh medium are contained in plastic bags placed side-by-side so the waste bag fills as the fresh medium bag is depleted. The compliance vessel contains a bladder to accommodate pressure transients that might damage the system. A peristolic pump moves fluid by squeezing the plastic tubing, thus avoiding potential contamination. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  14. The Potential for Microalgae as Bioreactors to Produce Pharmaceuticals.

    PubMed

    Yan, Na; Fan, Chengming; Chen, Yuhong; Hu, Zanmin

    2016-01-01

    As photosynthetic organisms, microalgae can efficiently convert solar energy into biomass. Microalgae are currently used as an important source of valuable natural biologically active molecules, such as carotenoids, chlorophyll, long-chain polyunsaturated fatty acids, phycobiliproteins, carotenoids and enzymes. Significant advances have been achieved in microalgae biotechnology over the last decade, and the use of microalgae as bioreactors for expressing recombinant proteins is receiving increased interest. Compared with the bioreactor systems that are currently in use, microalgae may be an attractive alternative for the production of pharmaceuticals, recombinant proteins and other valuable products. Products synthesized via the genetic engineering of microalgae include vaccines, antibodies, enzymes, blood-clotting factors, immune regulators, growth factors, hormones, and other valuable products, such as the anticancer agent Taxol. In this paper, we briefly compare the currently used bioreactor systems, summarize the progress in genetic engineering of microalgae, and discuss the potential for microalgae as bioreactors to produce pharmaceuticals. PMID:27322258

  15. The Potential for Microalgae as Bioreactors to Produce Pharmaceuticals

    PubMed Central

    Yan, Na; Fan, Chengming; Chen, Yuhong; Hu, Zanmin

    2016-01-01

    As photosynthetic organisms, microalgae can efficiently convert solar energy into biomass. Microalgae are currently used as an important source of valuable natural biologically active molecules, such as carotenoids, chlorophyll, long-chain polyunsaturated fatty acids, phycobiliproteins, carotenoids and enzymes. Significant advances have been achieved in microalgae biotechnology over the last decade, and the use of microalgae as bioreactors for expressing recombinant proteins is receiving increased interest. Compared with the bioreactor systems that are currently in use, microalgae may be an attractive alternative for the production of pharmaceuticals, recombinant proteins and other valuable products. Products synthesized via the genetic engineering of microalgae include vaccines, antibodies, enzymes, blood-clotting factors, immune regulators, growth factors, hormones, and other valuable products, such as the anticancer agent Taxol. In this paper, we briefly compare the currently used bioreactor systems, summarize the progress in genetic engineering of microalgae, and discuss the potential for microalgae as bioreactors to produce pharmaceuticals. PMID:27322258

  16. Miniaturized handheld hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Wu, Huawen; Haibach, Frederick G.; Bergles, Eric; Qian, Jack; Zhang, Charlie; Yang, William

    2014-05-01

    A miniaturized hyperspectral imager is enabled with image sensor integrated with dispersing elements in a very compact form factor, removing the need for expensive, moving, bulky and complex optics that have been used in conventional hyperspectral imagers for decades. The result is a handheld spectral imager that can be installed on miniature UAV drones or conveyor belts in production lines. Eventually, small handhelds can be adapted for use in outpatient medical clinics for point-of-care diagnostics and other in-field applications.

  17. Throw a Miniature Vase

    ERIC Educational Resources Information Center

    Sapiro, Maurice

    1977-01-01

    A direct correlation exists between the acquisition of skills on the potter's wheel and the vertical dimension of the finished pot. Ability equals height. Overlooked somewhere in the search for acquiring technical facility and a means of demonstrating it, is the fascinating world of miniature pottery. Describes the mechanics peculiar to small…

  18. Disposable Bioreactors for Plant Micropropagation and Mass Plant Cell Culture

    NASA Astrophysics Data System (ADS)

    Ducos, Jean-Paul; Terrier, Bénédicte; Courtois, Didier

    Different types of bioreactors are used at Nestlé R&D Centre - Tours for mass propagation of selected plant varieties by somatic embryogenesis and for large scale culture of plants cells to produce metabolites or recombinant proteins. Recent studies have been directed to cut down the production costs of these two processes by developing disposable cell culture systems. Vegetative propagation of elite plant varieties is achieved through somatic embryogenesis in liquid medium. A pilot scale process has recently been set up for the industrial propagation of Coffea canephora (Robusta coffee). The current production capacity is 3.0 million embryos per year. The pre-germination of the embryos was previously conducted by temporary immersion in liquid medium in 10-L glass bioreactors. An improved process has been developed using a 10-L disposable bioreactor consisting of a bag containing a rigid plastic box ('Box-in-Bag' bioreactor), insuring, amongst other advantages, a higher light transmittance to the biomass due to its horizontal design. For large scale cell culture, two novel flexible plastic-based disposable bioreactors have been developed from 10 to 100 L working volumes, validated with several plant species ('Wave and Undertow' and 'Slug Bubble' bioreactors). The advantages and the limits of these new types of bioreactor are discussed, based mainly on our own experience on coffee somatic embryogenesis and mass cell culture of soya and tobacco.

  19. NASA Bioreactor tissue culture

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  20. Miniaturized HTS technologies - uHTS.

    PubMed

    Wölcke, J; Ullmann, D

    2001-06-01

    The transition from slow, manual, low-throughput screening to industrialized robotic ultra-high throughput screening (uHTS) in the past few years has made it possible to screen hundreds of thousands of chemical entities against a biological target in a short time-frame. The need to minimize the cost of screening has been addressed primarily by reducing the volume of sample to be screened. This, in turn, has resulted in the miniaturization of HTS technology as a whole. Miniaturization requires new technologies and strategies for compound handling, assay development, assay adaptation, liquid handling and automation in addition to refinement of the technologies used for detection systems and data management. This review summarizes current trends in the field of uHTS and illustrates the technological developments that are necessary to enable the routine application of miniaturized uHTS systems within an industrial environment.

  1. In Vivo Bioreactors for Mandibular Reconstruction

    PubMed Central

    Tatara, A.M.; Wong, M.E.; Mikos, A.G.

    2014-01-01

    Large mandibular defects are difficult to reconstruct with good functional and aesthetic outcomes because of the complex geometry of craniofacial bone. While the current gold standard is free tissue flap transfer, this treatment is limited in fidelity by the shape of the harvested tissue and can result in significant donor site morbidity. To address these problems, in vivo bioreactors have been explored as an approach to generate autologous prefabricated tissue flaps. These bioreactors are implanted in an ectopic site in the body, where ossified tissue grows into the bioreactor in predefined geometries and local vessels are recruited to vascularize the developing construct. The prefabricated flap can then be harvested with vessels and transferred to a mandibular defect for optimal reconstruction. The objective of this review article is to introduce the concept of the in vivo bioreactor, describe important preclinical models in the field, summarize the human cases that have been reported through this strategy, and offer future directions for this exciting approach. PMID:25139360

  2. Miniaturization in Biocatalysis

    PubMed Central

    Fernandes, Pedro

    2010-01-01

    The use of biocatalysts for the production of both consumer goods and building blocks for chemical synthesis is consistently gaining relevance. A significant contribution for recent advances towards further implementation of enzymes and whole cells is related to the developments in miniature reactor technology and insights into flow behavior. Due to the high level of parallelization and reduced requirements of chemicals, intensive screening of biocatalysts and process variables has become more feasible and reproducibility of the bioconversion processes has been substantially improved. The present work aims to provide an overview of the applications of miniaturized reactors in bioconversion processes, considering multi-well plates and microfluidic devices, update information on the engineering characterization of the hardware used, and present perspective developments in this area of research. PMID:20479988

  3. Miniaturized Environmental Monitoring Instrumentation

    SciTech Connect

    C. B. Freidhoff

    1997-09-01

    The objective of the Mass Spectrograph on a Chip (MSOC) program is the development of a miniature, multi-species gas sensor fabricated using silicon micromachining technology which will be orders of magnitude smaller and lower power consumption than a conventional mass spectrometer. The sensing and discrimination of this gas sensor are based on an ionic mass spectrograph, using magnetic and/or electrostatic fields. The fields cause a spatial separation of the ions according to their respective mass-to-charge ratio. The fabrication of this device involves the combination of microelectronics with micromechanically built sensors and, ultimately, vacuum pumps. The prototype of a chemical sensor would revolutionize the method of performing environmental monitoring for both commercial and government applications. The portable unit decided upon was the miniaturized gas chromatograph with a mass spectrometer detector, referred to as a GC/MS in the analytical marketplace.

  4. Miniature ceramic fuel cell

    DOEpatents

    Lessing, Paul A.; Zuppero, Anthony C.

    1997-06-24

    A miniature power source assembly capable of providing portable electricity is provided. A preferred embodiment of the power source assembly employing a fuel tank, fuel pump and control, air pump, heat management system, power chamber, power conditioning and power storage. The power chamber utilizes a ceramic fuel cell to produce the electricity. Incoming hydro carbon fuel is automatically reformed within the power chamber. Electrochemical combustion of hydrogen then produces electricity.

  5. Miniature multichannel biotelemeter system

    NASA Technical Reports Server (NTRS)

    Carraway, J. B.; Sumida, J. T. (Inventor)

    1974-01-01

    A miniature multichannel biotelemeter system is described. The system includes a transmitter where signals from different sources are sampled to produce a wavetrain of pulses. The transmitter also separates signals by sync pulses. The pulses amplitude modulate a radio frequency carrier which is received at a receiver unit. There the sync pulses are detected by a demultiplexer which routes the pulses from each different source to a separate output channel where the pulses are used to reconstruct the signals from the particular source.

  6. Miniaturized photoacoustic spectrometer

    DOEpatents

    Okandan, Murat; Robinson, Alex; Nielson, Gregory N.; Resnick, Paul J.

    2016-08-09

    A low-power miniaturized photoacoustic sensor uses an optical microphone made by semiconductor fabrication techniques, and optionally allows for all-optical communication to and from the sensor. This allows integration of the photoacoustic sensor into systems with special requirements, such as those that would be reactive in an electrical discharge condition. The photoacoustic sensor can also be operated in various other modes with wide application flexibility.

  7. Miniaturizing RFID for magnamosis.

    PubMed

    Jiang, Hao; Chen, Shijie; Kish, Shad; Loh, Lokkee; Zhang, Junmin; Zhang, Xiaorong; Kwiat, Dillon; Harrison, Michael; Roy, Shuvo

    2014-01-01

    Anastomosis is a common surgical procedure using staples or sutures in an open or laparoscopic surgery. A more effective and much less invasive alternative is to apply the mechanical pressure on the tissue over a few days [1]. Since the pressure is produced by the attractive force between two permanent magnets, the procedure is called magnamosis[1]. To ensure the two magnets are perfectly aligned during the surgery, a miniaturized batteryless Radio Frequency IDentification (RFID) tag is developed to wirelessly telemeter the status of a pressure sensitive mechanical switch. Using the multi-layer circular spiral coil design, the diameter of the RFID tag is shrunk to 10, 15, 19 and 27 mm to support the magnamosis for children as well as adults. With the impedance matching network, the operating distance of these four RFID tags are longer than 10 cm in a 20 × 22 cm(2) area, even when the tag's normal direction is 45° off the antenna's normal direction. Measurement results also indicate that there is no noticeable degradation on the operating distance when the tag is immersed in saline or placed next to the rare-earth magnet. The miniaturized RFID tag presented in this paper is able to support the magnamosis and other medical applications that require the miniaturized RFID tag.

  8. BioReactor

    2003-04-18

    BioReactor is a simulation tool kit for modeling networks of coupled chemical processes (or similar productions rules). The tool kit is implemented in C++ and has the following functionality: 1. Monte Carlo discrete event simulator 2. Solvers for ordinary differential equations 3. Genetic algorithm optimization routines for reverse engineering of models using either Monte Carlo or ODE representation )i.e., 1 or 2)

  9. Oscillating Cell Culture Bioreactor

    NASA Technical Reports Server (NTRS)

    Freed, Lisa E.; Cheng, Mingyu; Moretti, Matteo G.

    2010-01-01

    To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid

  10. Miniaturized flow injection analysis system

    DOEpatents

    Folta, James A.

    1997-01-01

    A chemical analysis technique known as flow injection analysis, wherein small quantities of chemical reagents and sample are intermixed and reacted within a capillary flow system and the reaction products are detected optically, electrochemically, or by other means. A highly miniaturized version of a flow injection analysis system has been fabricated utilizing microfabrication techniques common to the microelectronics industry. The microflow system uses flow capillaries formed by etching microchannels in a silicon or glass wafer followed by bonding to another wafer, commercially available microvalves bonded directly to the microflow channels, and an optical absorption detector cell formed near the capillary outlet, with light being both delivered and collected with fiber optics. The microflow system is designed mainly for analysis of liquids and currently measures 38.times.25.times.3 mm, but can be designed for gas analysis and be substantially smaller in construction.

  11. Miniaturized flow injection analysis system

    DOEpatents

    Folta, J.A.

    1997-07-01

    A chemical analysis technique known as flow injection analysis is described, wherein small quantities of chemical reagents and sample are intermixed and reacted within a capillary flow system and the reaction products are detected optically, electrochemically, or by other means. A highly miniaturized version of a flow injection analysis system has been fabricated utilizing microfabrication techniques common to the microelectronics industry. The microflow system uses flow capillaries formed by etching microchannels in a silicon or glass wafer followed by bonding to another wafer, commercially available microvalves bonded directly to the microflow channels, and an optical absorption detector cell formed near the capillary outlet, with light being both delivered and collected with fiber optics. The microflow system is designed mainly for analysis of liquids and currently measures 38{times}25{times}3 mm, but can be designed for gas analysis and be substantially smaller in construction. 9 figs.

  12. Bioreactor Development for Lung Tissue Engineering

    PubMed Central

    Panoskaltsis-Mortari, Angela

    2015-01-01

    Rationale Much recent interest in lung bioengineering by pulmonary investigators, industry and the organ transplant field has seen a rapid growth of bioreactor development ranging from the microfluidic scale to the human-sized whole lung systems. A comprehension of the findings from these models is needed to provide the basis for further bioreactor development. Objective The goal was to comprehensively review the current state of bioreactor development for the lung. Methods A search using PubMed was done for published, peer-reviewed papers using the keywords “lung” AND “bioreactor” or “bioengineering” or “tissue engineering” or “ex vivo perfusion”. Main Results Many new bioreactors ranging from the microfluidic scale to the human-sized whole lung systems have been developed by both academic and commercial entities. Microfluidic, lung-mimic and lung slice cultures have the advantages of cost-efficiency and high throughput analyses ideal for pharmaceutical and toxicity studies. Perfused/ventilated rodent whole lung systems can be adapted for mid-throughput studies of lung stem/progenitor cell development, cell behavior, understanding and treating lung injury and for preliminary work that can be translated to human lung bioengineering. Human-sized ex vivo whole lung bioreactors incorporating perfusion and ventilation are amenable to automation and have been used for whole lung decellularization and recellularization. Clinical scale ex vivo lung perfusion systems have been developed for lung preservation and reconditioning and are currently being evaluated in clinical trials. Conclusions Significant advances in bioreactors for lung engineering have been made at both the microfluidic and the macro scale. The most advanced are closed systems that incorporate pressure-controlled perfusion and ventilation and are amenable to automation. Ex vivo lung perfusion systems have advanced to clinical trials for lung preservation and reconditioning. The biggest

  13. Design challenges for space bioreactors

    NASA Technical Reports Server (NTRS)

    Seshan, P. K.; Petersen, G. R.

    1989-01-01

    The design of bioreactors for operation under conditions of microgravity presents problems and challenges. Absence of a significant body force such as gravity can have profound consequences for interfacial phenomena. Marangoni convection can no longer be overlooked. Many speculations on the advantages and benefits of microgravity can be found in the literature. Initial bioreactor research considerations for space applications had little regard for the suitability of the designs for conditions of microgravity. Bioreactors can be classified in terms of their function and type of operation. The complex interaction of parameters leading to optimal design and operation of a bioreactor is illustrated by the JSC mammalian cell culture system. The design of a bioreactor is strongly dependent upon its intended use as a production unit for cell mass and/or biologicals or as a research reactor for the study of cell growth and function. Therefore a variety of bioreactor configurations are presented in rapid summary. Following this, a rationale is presented for not attempting to derive key design parameters such as the oxygen transfer coefficient from ground-based data. A set of themes/objectives for flight experiments to develop the expertise for design of space bioreactors is then proposed for discussion. These experiments, carried out systematically, will provide a database from which engineering tools for space bioreactor design will be derived.

  14. Miniature Laser Magnetometer

    NASA Technical Reports Server (NTRS)

    Slocum, Robert; Brown, Andy

    2011-01-01

    A conceptual design has been developed for a miniature laser magnetometer (MLM) that will measure the scalar magnitude and vector components of near-Earth magnetic fields. The MLM incorporates a number of technical innovations to achieve high-accuracy and high-resolution performance while significantly reducing the size of the laser-pumped helium magnetometer for use on small satellites and unmanned aerial vehicles (UAVs). and electronics sections that has the capability of measuring both the scalar magnetic field magnitude and the vector magnetic field components. Further more, the high-accuracy scalar measurements are used to calibrate and correct the vector component measurements in order to achieve superior vector accuracy and stability. The correction algorithm applied to the vector components for calibration and the same cell for vector and scalar measurements are major innovations. The separate sensor and electronics section of the MLM instrument allow the sensor to be installed on a boom or otherwise located away from electronics and other noisy magnetic components. The MLM s miniaturization will be accomplished through the use of advanced miniaturized components and packaging methods for the MLM sensor and electronics. The MLM conceptual design includes three key innovations. The first is a new non-magnetic laser package that will allow the placement of the laser pump source near the helium cell sensing elements. The second innovation is the design of compact, nested, triaxial Braunbek coils used in the vector measurements that reduce the coil size by a factor of two compared to existing Helmholtz coils with similar field-generation performance. The third innovation is a compact sensor design that reduces the sensor volume by a factor of eight compared to MLM s predecessor.

  15. Mars Miniature Science Instruments

    NASA Technical Reports Server (NTRS)

    Kim, Soon Sam; Hayati, Samad; Lavery, David; McBrid, Karen

    2006-01-01

    For robotic Mars missions, all the science information is gathered through on-board miniature instruments that have been developed through many years of R&D. Compared to laboratory counterparts, the rover instruments require miniaturization, such as low mass (1-2 kg), low power (> 10 W) and compact (1-2 liter), yet with comparable sensitivity. Since early 1990's, NASA recognized the need for the miniature instruments and launched several instrument R&D programs, e.g., PIDDP (Planetary Instrument Definition and Development). However, until 1998, most of the instrument R&D programs supported only up to a breadboard level (TRL 3, 4) and there is a need to carry such instruments to flight qualifiable status (TU 5, 6) to respond to flight AOs (Announcement of Opportunity). Most of flight AOs have only limited time and financial resources, and can not afford such instrument development processes. To bridge the gap between instrument R&D programs and the flight instrument needs, NASA's Mars Technology Program (MTP) created advanced instrumentation program, Mars Instrument Development Project (MIDP). MIDP candidate instruments are selected through NASA Research Announcement (NRA) process [l]. For example, MIDP 161998-2000) selected and developed 10 instruments, MIDP II (2003-2005) 16 instruments, and MIDP III (2004-2006) II instruments.Working with PIs, JPL has been managing the MIDP tasks since September 1998. All the instruments being developed under MIDP have been selected through a highly competitive NRA process, and employ state-of-the-art technology. So far, four MIDP funded instruments have been selected by two Mars missions (these instruments have further been discussed in this paper).

  16. Miniaturized radiation chirper

    DOEpatents

    Umbarger, C. John; Wolf, Michael A.

    1980-01-01

    The disclosure relates to a miniaturized radiation chirper for use with a small battery supplying on the order of 5 volts. A poor quality CdTe crystal which is not necessarily suitable for high resolution gamma ray spectroscopy is incorporated with appropriate electronics so that the chirper emits an audible noise at a rate that is proportional to radiation exposure level. The chirper is intended to serve as a personnel radiation warning device that utilizes new and novel electronics with a novel detector, a CdTe crystal. The resultant device is much smaller and has much longer battery life than existing chirpers.

  17. Bioreactor and process design for biohydrogen production.

    PubMed

    Show, Kuan-Yeow; Lee, Duu-Jong; Chang, Jo-Shu

    2011-09-01

    Biohydrogen is regarded as an attractive future clean energy carrier due to its high energy content and environmental-friendly conversion. It has the potential for renewable biofuel to replace current hydrogen production which rely heavily on fossil fuels. While biohydrogen production is still in the early stage of development, there have been a variety of laboratory- and pilot-scale systems developed with promising potential. This work presents a review of advances in bioreactor and bioprocess design for biohydrogen production. The state-of-the art of biohydrogen production is discussed emphasizing on production pathways, factors affecting biohydrogen production, as well as bioreactor configuration and operation. Challenges and prospects of biohydrogen production are also outlined.

  18. Bioreactor and process design for biohydrogen production.

    PubMed

    Show, Kuan-Yeow; Lee, Duu-Jong; Chang, Jo-Shu

    2011-09-01

    Biohydrogen is regarded as an attractive future clean energy carrier due to its high energy content and environmental-friendly conversion. It has the potential for renewable biofuel to replace current hydrogen production which rely heavily on fossil fuels. While biohydrogen production is still in the early stage of development, there have been a variety of laboratory- and pilot-scale systems developed with promising potential. This work presents a review of advances in bioreactor and bioprocess design for biohydrogen production. The state-of-the art of biohydrogen production is discussed emphasizing on production pathways, factors affecting biohydrogen production, as well as bioreactor configuration and operation. Challenges and prospects of biohydrogen production are also outlined. PMID:21624834

  19. Miniaturization of Planar Horn Motors

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Ostlund, Patrick N.; Chang, Zensheu; Bao, Xiaoqi; Bar-Cohen, Yoseph; Widholm, Scott E.; Badescu, Mircea

    2012-01-01

    There is a great need for compact, efficient motors for driving various mechanisms including robots or mobility platforms. A study is currently underway to develop a new type of piezoelectric actuators with significantly more strength, low mass, small footprint, and efficiency. The actuators/motors utilize piezoelectric actuated horns which have a very high power density and high electromechanical conversion efficiency. The horns are fabricated using our recently developed novel pre-stress flexures that make them thermally stable and increases their coupling efficiency. The monolithic design and integrated flexures that pre-stresses the piezoelectric stack eliminates the use of stress bolt. This design allows embedding solid-state motors and actuators in any structure so that the only macroscopically moving parts are the rotor or the linear translator. The developed actuator uses a stack/horn actuation and has a Barth motor configuration, which potentially generates very large torque and speeds that do not require gearing. Finite element modeling and design tools were investigated to determine the requirements and operation parameters and the results were used to design and fabricate a motor. This new design offers a highly promising actuation mechanism that can potentially be miniaturized and integrated into systems and structures. It can be configured in many shapes to operate as multi-degrees of freedom and multi-dimensional motors/actuators including unidirectional, bidirectional, 2D and 3D. In this manuscript, we are reporting the experimental measurements from a bench top design and the results from the efforts to miniaturize the design using 2x2x2 mm piezoelectric stacks integrated into thin plates that are of the order of3 x 3x 0.2 cm.

  20. Miniaturization of planar horn motors

    NASA Astrophysics Data System (ADS)

    Sherrit, Stewart; Ostlund, Patrick N.; Chang, Zensheu; Bao, Xiaoqi; Bar-Cohen, Yoseph; Widholm, Scott E.; Badescu, Mircea

    2012-04-01

    There is a great need for compact, efficient motors for driving various mechanisms including robots or mobility platforms. A study is currently underway to develop a new type of piezoelectric actuators with significantly more strength, low mass, small footprint, and efficiency. The actuators/motors utilize piezoelectric actuated horns which have a very high power density and high electromechanical conversion efficiency. The horns are fabricated using our recently developed novel pre-stress flexures that make them thermally stable and increases their coupling efficiency. The monolithic design and integrated flexures that pre-stresses the piezoelectric stack eliminates the use of a stress bolt. This design allows embedding solid-state motors and actuators in any structure so that the only macroscopically moving parts are the rotor or the linear translator. The developed actuator uses a stack/horn actuation and has a Barth motor configuration, which potentially generates very large torque and speeds that do not require gearing. Finite element modeling and design tools were investigated to determine the requirements and operation parameters and the results were used to design and fabricate a motor. This new design offers a highly promising actuation mechanism that can potentially be miniaturized and integrated into systems and structures. It can be configured in many shapes to operate as multi-degrees of freedom and multi-dimensional motors/actuators including unidirectional, bidirectional, 2D and 3D. In this manuscript, we are reporting the experimental measurements from a bench top design and the results from the efforts to miniaturize the design using 2×2×2 mm piezoelectric stacks integrated into thin plates that are of the order of 3 × 3 × 0.2 cm.

  1. Perfusion Bioreactor Module

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.

    1990-01-01

    Perfusion bioreactor module, self-contained, closed-loop cell-culture system that operates in microgravity or on Earth. Equipment supports growth or long-term maintenance of cultures of human or other fragile cells for experiments in basic cell biology or process technology. Designed to support proliferation (initially at exponential rates of growth) of cells in complex growth medium and to maintain confluent cells in defined medium under conditions optimized to permit or encourage selected functions of cells, including secretion of products of cells into medium.

  2. Perspectives on Simulation and Miniaturization.

    ERIC Educational Resources Information Center

    McCluskey, Michael R.

    Training applications of simulation and miniaturization are examined, as are areas where research is needed to develop cost-effectiveness simulation methodologies for training. In order for simulation and miniaturization techniques to reach maximum levels of effectiveness, systems analysis is needed to define physical and psychological dimensions,…

  3. Miniature Ion-Array Spectrometer

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.

    2006-01-01

    A figure is shown that depicts a proposed miniature ion-mobility spectrometer that would share many features of design and operation of the instrument described in another article. The main differences between that instrument and this one would lie in the configuration and mode of operation of the filter and detector electrodes. A filter electrode and detector electrodes would be located along the sides of a drift tube downstream from the accelerator electrode. These electrodes would apply a combination of (1) a transverse AC electric field that would effect differential transverse dispersal of ions and (2) a transverse DC electric field that would drive the dispersed ions toward the detector electrodes at different distances along the drift tube. The electric current collected by each detector electrode would be a measure of the current, and thus of the abundance of the species of ions impinging on that electrode. The currents collected by all the detector electrodes could be measured simultaneously to obtain continuous readings of abundances of species. The downstream momentum of accelerated ions would be maintained through neutralization on the electrodes; the momentum of the resulting neutral atoms would serve to expel gases from spectrometer, without need for a pump.

  4. Microtechnology in space bioreactors.

    PubMed

    Walther, I; van der Schoot, B; Boillat, M; Muller, O; Cogoli, A

    1999-03-01

    Space biology is a young and rapidly developing discipline comprising basic research and biotechnology. In the next decades it will play a prominent role in the International Space Station (ISS). Therefore, there is an increasing demand for sophisticated instrumentation to satisfy the requirements of the future projects in space biology. Bioreactors will be needed to supply fresh living material (cells and tissues) either to study still obscure basic biological mechanisms or to develop profitable bioprocesses which will take advantage of the peculiar microgravity conditions. Since more than twenty years, the Space Biology Group of the ETHZ is carrying out research projects in space (Space Shuttle/Spacelab, MIR Station, satellites, and sounding rockets) that involve also the development of space-qualified instrumentation. In the last ten years we have developed, in collaboration with Mecanex SA, Nyon, and the Institute of Microtechnology of the University of Neuchatel, a space bioreactor for the continuous culture of yeast cells under controlled conditions. Sensors, pH control, nutrients pump and fluid flowmeter are based on state-of-the-art silicon technology. After two successful space flights, a further improved version is presently prepared for a flight in the year 2000.

  5. Sensing in tissue bioreactors

    NASA Astrophysics Data System (ADS)

    Rolfe, P.

    2006-03-01

    Specialized sensing and measurement instruments are under development to aid the controlled culture of cells in bioreactors for the fabrication of biological tissues. Precisely defined physical and chemical conditions are needed for the correct culture of the many cell-tissue types now being studied, including chondrocytes (cartilage), vascular endothelial cells and smooth muscle cells (blood vessels), fibroblasts, hepatocytes (liver) and receptor neurones. Cell and tissue culture processes are dynamic and therefore, optimal control requires monitoring of the key process variables. Chemical and physical sensing is approached in this paper with the aim of enabling automatic optimal control, based on classical cell growth models, to be achieved. Non-invasive sensing is performed via the bioreactor wall, invasive sensing with probes placed inside the cell culture chamber and indirect monitoring using analysis within a shunt or a sampling chamber. Electroanalytical and photonics-based systems are described. Chemical sensing for gases, ions, metabolites, certain hormones and proteins, is under development. Spectroscopic analysis of the culture medium is used for measurement of glucose and for proteins that are markers of cell biosynthetic behaviour. Optical interrogation of cells and tissues is also investigated for structural analysis based on scatter.

  6. Cells growing in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. Shown here, clusters of cells slowly spin inside a bioreactor. On Earth, the cells continually fall through the buffer medium and never hit bottom. In space, they are naturally suspended. Rotation ensures gentle stirring so waste is removed and fresh nutrient and oxygen are supplied. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  7. Bioreactor Engineering of Stem Cell Environments

    PubMed Central

    Tandon, Nina; Marolt, Darja; Cimetta, Elisa; Vunjak-Novakovic, Gordana

    2013-01-01

    Stem cells hold promise to revolutionize modern medicine by development of new therapies, disease models and drug screening systems. Standard cell culture systems have limited biological relevance because they do not recapitulate the complex 3-dimensional interactions and biophysical cues that characterize the in vivo environment. In this review, we discuss the current advances in engineering stem cell environments using novel biomaterials and bioreactor technologies. We also reflect on the challenges the field is currently facing with regard to translation of stem cell based therapies into the clinic. PMID:23531529

  8. Miniature, ruggedized data collector

    NASA Astrophysics Data System (ADS)

    Jackson, Scott; Calcutt, Wade; Knobler, Ron; Jones, Barry; Klug, Robert

    2009-05-01

    McQ has developed a miniaturized, programmable, ruggedized data collector intended for use in weapon testing or data collection exercises that impose severe stresses on devices under test. The recorder is designed to survive these stresses which include acceleration and shock levels up to 100,000 G. The collector acquires and stores up to four channels of signal data to nonvolatile memory for later retrieval by a user. It is small (< 7 in3), light weight (< 1 lb), and can operate from various battery chemistries. A built-in menuing system, accessible via a USB interface, allows the user to configure parameters of the recorder operation, such as channel gain, filtering, and signal offsets, and also to retrieve recorded data for analysis. An overview of the collector, its features, performance, and potential uses, is presented.

  9. Miniature spectrally selective dosimeter

    NASA Technical Reports Server (NTRS)

    Adams, R. R.; Macconochie, I. O.; Poole, B. D., Jr. (Inventor)

    1980-01-01

    A miniature spectrally selective dosimeter capable of measuring selected bandwidths of radiation exposure on small mobile areas is described. This is achieved by the combination of photovoltaic detectors, electrochemical integrators (E-cells) and filters in a small compact case which can be easily attached in close proximity to and substantially parallel to the surface being measured. In one embodiment two photovoltaic detectors, two E-cells, and three filters are packaged in a small case with attaching means consisting of a safety pin. In another embodiment, two detectors, one E-cell, three filters are packaged in a small case with attaching means consisting of a clip to clip over a side piece of an eye glass frame.

  10. Bioreactor design for clinical-grade expansion of stem cells.

    PubMed

    dos Santos, Francisco F; Andrade, Pedro Z; da Silva, Cláudia Lobato; Cabral, Joaquim M S

    2013-06-01

    The many clinical trials currently in progress will likely lead to the widespread use of stem cell-based therapies for an extensive variety of diseases, either in autologous or allogeneic settings. With the current pace of progress, in a few years' time, the field of stem cell-based therapy should be able to respond to the market demand for safe, robust and clinically efficient stem cell-based therapeutics. Due to the limited number of stem cells that can be obtained from a single donor, one of the major challenges on the roadmap for regulatory approval of such medicinal products is the expansion of stem cells using Good Manufacturing Practices (GMP)-compliant culture systems. In fact, manufacturing costs, which include production and quality control procedures, may be the main hurdle for developing cost-effective stem cell therapies. Bioreactors provide a viable alternative to the traditional static culture systems in that bioreactors provide the required scalability, incorporate monitoring and control tools, and possess the operational flexibility to be adapted to the differing requirements imposed by various clinical applications. Bioreactor systems face a number of issues when incorporated into stem cell expansion protocols, both during development at the research level and when bioreactors are used in on-going clinical trials. This review provides an overview of the issues that must be confronted during the development of GMP-compliant bioreactors systems used to support the various clinical applications employing stem cells. PMID:23625834

  11. Cultivation of mammalian cells using a single-use pneumatic bioreactor system.

    PubMed

    Obom, Kristina M; Cummings, Patrick J; Ciafardoni, Janelle A; Hashimura, Yasunori; Giroux, Daniel

    2014-10-10

    Recent advances in mammalian, insect, and stem cell cultivation and scale-up have created tremendous opportunities for new therapeutics and personalized medicine innovations. However, translating these advances into therapeutic applications will require in vitro systems that allow for robust, flexible, and cost effective bioreactor systems. There are several bioreactor systems currently utilized in research and commercial settings; however, many of these systems are not optimal for establishing, expanding, and monitoring the growth of different cell types. The culture parameters most challenging to control in these systems include, minimizing hydrodynamic shear, preventing nutrient gradient formation, establishing uniform culture medium aeration, preventing microbial contamination, and monitoring and adjusting culture conditions in real-time. Using a pneumatic single-use bioreactor system, we demonstrate the assembly and operation of this novel bioreactor for mammalian cells grown on micro-carriers. This bioreactor system eliminates many of the challenges associated with currently available systems by minimizing hydrodynamic shear and nutrient gradient formation, and allowing for uniform culture medium aeration. Moreover, the bioreactor's software allows for remote real-time monitoring and adjusting of the bioreactor run parameters. This bioreactor system also has tremendous potential for scale-up of adherent and suspension mammalian cells for production of a variety therapeutic proteins, monoclonal antibodies, stem cells, biosimilars, and vaccines.

  12. Design considerations for miniaturized PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Meyers, Jeremy P.; Maynard, Helen L.

    In this paper, we consider the design of a miniaturized proton-exchange membrane (PEM) fuel cell for powering 0.5-20 W portable telecommunication and computing devices. Our design is implemented on a silicon substrate to take advantage of advanced silicon processing technology in order to minimize production costs. The reduced length scales afforded by silicon processing allow us to consider designs that would be prohibited by excessive Ohmic losses in larger systems. We employ a mathematical model to quantify the effects of the secondary current distribution on two competing cell designs. In addition to the design of the cell itself, we discuss key integration issues and engineering trade-offs relevant to all miniaturized fuel cell systems: air movement, fuel delivery and water balance, thermal management and load handling.

  13. Producing miniature threads. Final report

    SciTech Connect

    Gillespie, L.K.; Robb, J.M.

    1981-11-01

    Miniature precision actuators, timers, and switches typically utilize miniature threads to provide convenient assembly, disassembly and adjustment. Thread rolling provides high-quality external threads with greater strength and lower cost than other thread-producing techniques. Tap breakage is a significant problem when 0.5 and 0.6 Unified National Miniature (UNM) threads must be produced in hard materials such as SAE K95100 high-permeability magnetic steel. Aluminum parts can be tapped with no difficulty in these sizes. Stainless steel 0.5 UNM screws break at loads of 21 lb (53 N). Thread failure occurs at thread heights of 62% full thread or lower.

  14. Spiral vane bioreactor

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Inventor)

    1991-01-01

    A spiral vane bioreactor of a perfusion type is described in which a vertical chamber, intended for use in a microgravity condition, has a central rotating filter assembly and has flexible membranes disposed to rotate annularly about the filter assembly. The flexible members have end portions disposed angularly with respect to one another. A fluid replenishment medium is input from a closed loop liquid system to a completely liquid filled chamber containing microcarrier beads, cells and a fluid medium. Output of spent medium is to the closed loop. In the closed loop, the output and input parameters are sensed by sensors. A manifold permits recharging of the nutrients and pH adjustment. Oxygen is supplied and carbon dioxide and bubbles are removed and the system is monitored and controlled by a microprocessor.

  15. Controlled-Turbulence Bioreactors

    NASA Technical Reports Server (NTRS)

    Wolf, David A.; Schwartz, Ray; Trinh, Tinh

    1989-01-01

    Two versions of bioreactor vessel provide steady supplies of oxygen and nutrients with little turbulence. Suspends cells in environment needed for sustenance and growth, while inflicting less damage from agitation and bubbling than do propeller-stirred reactors. Gentle environments in new reactors well suited to delicate mammalian cells. One reactor kept human kidney cells alive for as long as 11 days. Cells grow on carrier beads suspended in liquid culture medium that fills cylindrical housing. Rotating vanes - inside vessel but outside filter - gently circulates nutrient medium. Vessel stationary; magnetic clutch drives filter cylinder and vanes. Another reactor creates even less turbulence. Oxygen-permeable tubing wrapped around rod extending along central axis. Small external pump feeds oxygen to tubing through rotary coupling, and oxygen diffuses into liquid medium.

  16. Membrane Bioreactor With Pressure Cycle

    NASA Technical Reports Server (NTRS)

    Efthymiou, George S.; Shuler, Michael L.

    1991-01-01

    Improved class of multilayer membrane bioreactors uses convention forced by differences in pressure to overcome some of diffusional limitations of prior bioreactors. In reactor of new class, flow of nutrient solution reduces adverse gradients of concentration, keeps cells supplied with fresh nutrient, and sweeps away products faster than diffusion alone. As result, overall yield and rate of reaction increased. Pressures in sweeping gas and nutrient alternated to force nutrient liquid into and out of biocatalyst layer through hyrophilic membrane.

  17. Bioreactor Mass Transport Studies

    NASA Technical Reports Server (NTRS)

    Kleis, Stanley J.; Begley, Cynthia M.

    1997-01-01

    The objectives of the proposed research efforts were to develop both a simulation tool and a series of experiments to provide a quantitative assessment of mass transport in the NASA rotating wall perfused vessel (RWPV) bioreactor to be flown on EDU#2. This effort consisted of a literature review of bioreactor mass transport studies, the extension of an existing scalar transport computer simulation to include production and utilization of the scalar, and the evaluation of experimental techniques for determining mass transport in these vessels. Since mass transport at the cell surface is determined primarily by the relative motion of the cell assemblage and the surrounding fluid, a detailed assessment of the relative motion was conducted. Results of the simulations of the motion of spheres in the RWPV under microgravity conditions are compared with flight data from EDU#1 flown on STS-70. The mass transport across the cell membrane depends upon the environment, the cell type, and the biological state of the cell. Results from a literature review of cell requirements of several scalars are presented. As a first approximation, a model with a uniform spatial distribution of utilization or production was developed and results from these simulations are presented. There were two candidate processes considered for the experimental mass transport evaluations. The first was to measure the dissolution rate of solid or gel beads. The second was to measure the induced fluorescence of beads as a stimulant (for example hydrogen peroxide) is infused into the vessel. Either technique would use video taped images of the process for recording the quantitative results. Results of preliminary tests of these techniques are discussed.

  18. Development of foamed emulsion bioreactor for air pollution control.

    PubMed

    Kan, Eunsung; Deshusses, Marc A

    2003-10-20

    A new type of bioreactor for air pollution control has been developed. The new process relies on an organic-phase emulsion and actively growing pollutant-degrading microorganisms, made into a foam with the air being treated. This new reactor is referred to as a foamed emulsion bioreactor (FEBR). As there is no packing in the reactor, the FEBR is not subject to clogging. Mathematical modeling of the process and proof of concept using a laboratory prototype revealed that the foamed emulsion bioreactor greatly surpasses the performance of existing gas-phase bioreactors. Experimental results showed a toluene elimination capacity as high as 285 g(toluene) m(-3) (reactor) h(-1) with a removal efficiency of 95% at a gas residence time of 15 s and a toluene inlet concentration of 1-1.3 g x m(-3). Oxygen limited the reactor performance at toluene concentration above about 0.7-1.0 g x m(-3); consequently, performance was significantly improved when pure oxygen was added to the contaminated air. The elimination capacity increased from 204 to 408 g x m(-3) h(-1) with >77% toluene removal at toluene inlet concentrations of 2-2.2 g x m(-3). Overall, the results show that the performance of the FEBR far exceeds that of currently used bioreactors for air pollution control.

  19. Bioreactor control improves bioprocess performance.

    PubMed

    Simutis, Rimvydas; Lübbert, Andreas

    2015-08-01

    The performance of bioreactors is not only determined by productivity but also by process quality, which is mainly determined by variances in the process variables. As fluctuations in these quantities directly affect the variability in the product properties, combatting distortions is the main task of practical quality assurance. The straightforward way of reducing this variability is keeping the product formation process tightly under control. Purpose of this keynote is to show that there is enough evidence in literature showing that the performance of the fermentation processes can significantly be improved by feedback control. Most of the currently used open loop control procedures can be replaced by relatively simple feedback techniques. It is shown by practical examples that such a retrofitting does not require significant changes in the well-established equipment. Feedback techniques are best in assuring high reproducibility of the industrial cultivation processes and thus in assuring the quality of their products. Many developments in supervising and controlling industrial fermentations can directly be taken over in manufacturing processes. Even simple feedback controllers can efficiently improve the product quality. It's the time now that manufacturers follow the developments in most other industries and improve process quality by automatic feedback control. PMID:26228573

  20. Bioreactor control improves bioprocess performance.

    PubMed

    Simutis, Rimvydas; Lübbert, Andreas

    2015-08-01

    The performance of bioreactors is not only determined by productivity but also by process quality, which is mainly determined by variances in the process variables. As fluctuations in these quantities directly affect the variability in the product properties, combatting distortions is the main task of practical quality assurance. The straightforward way of reducing this variability is keeping the product formation process tightly under control. Purpose of this keynote is to show that there is enough evidence in literature showing that the performance of the fermentation processes can significantly be improved by feedback control. Most of the currently used open loop control procedures can be replaced by relatively simple feedback techniques. It is shown by practical examples that such a retrofitting does not require significant changes in the well-established equipment. Feedback techniques are best in assuring high reproducibility of the industrial cultivation processes and thus in assuring the quality of their products. Many developments in supervising and controlling industrial fermentations can directly be taken over in manufacturing processes. Even simple feedback controllers can efficiently improve the product quality. It's the time now that manufacturers follow the developments in most other industries and improve process quality by automatic feedback control.

  1. Noise in miniature microphones.

    PubMed

    Thompson, Stephen C; LoPresti, Janice L; Ring, Eugene M; Nepomuceno, Henry G; Beard, John J; Ballad, William J; Carlson, Elmer V

    2002-02-01

    The internal noise spectrum in miniature electret microphones of the type used in the manufacture of hearing aids is measured. An analogous circuit model of the microphone is empirically fit to the measured data and used to determine the important sources of noise within the microphone. The dominant noise source is found to depend on the frequency. Below 40 Hz and above 9 kHz, the dominant source is electrical noise from the amplifier circuit needed to buffer the electrical signal from the microphone diaphragm. Between approximately 40 Hz and 1 kHz, the dominant source is thermal noise originating in the acoustic flow resistance of the small hole pierced in the diaphragm to equalize barometric pressure. Between approximately 1 kHz and 9 kHz, the noise originates in the acoustic flow resistances of sound entering the microphone and propagating to the diaphragm. To further reduce the microphone internal noise in the audio band requires attacking these sources. A prototype microphone having reduced acoustical noise is measured and discussed. PMID:11863188

  2. Miniature Chemical Sensor

    SciTech Connect

    Andrew C. R. Pipino

    2004-12-13

    A new chemical detection technology has been realized that addresses DOE environmental management needs. The new technology is based on a variant of the sensitive optical absorption technique, cavity ring-down spectroscopy (CRDS). Termed evanescent-wave cavity ring-down spectroscopy (EW-CRDS), the technology employs a miniature solid-state optical resonator having an extremely high Q-factor as the sensing element, where the high-Q is achieved by using ultra-low-attenuation optical materials, ultra-smooth surfaces, and ultra-high reflectivity coatings, as well as low-diffraction-loss designs. At least one total-internal reflection (TIR) mirror is integral to the resonator permitting the concomitant evanescent wave to probe the ambient environment. Several prototypes have been designed, fabricated, characterized, and applied to chemical detection. Moreover, extensions of the sensing concept have been explored to enhance selectivity, sensitivity, and range of application. Operating primarily in the visible and near IR regions, the technology inherently enables remote detection by optical fiber. Producing 11 archival publications, 5 patents, 19 invited talks, 4 conference proceedings, a CRADA, and a patent-license agreement, the project has realized a new chemical detection technology providing >100 times more sensitivity than comparable technologies, while also providing practical advantages.

  3. Noise in miniature microphones

    NASA Astrophysics Data System (ADS)

    Thompson, Stephen C.; Lopresti, Janice L.; Ring, Eugene M.; Nepomuceno, Henry G.; Beard, John J.; Ballad, William J.; Carlson, Elmer V.

    2002-02-01

    The internal noise spectrum in miniature electret microphones of the type used in the manufacture of hearing aids is measured. An analogous circuit model of the microphone is empirically fit to the measured data and used to determine the important sources of noise within the microphone. The dominant noise source is found to depend on the frequency. Below 40 Hz and above 9 kHz, the dominant source is electrical noise from the amplifier circuit needed to buffer the electrical signal from the microphone diaphragm. Between approximately 40 Hz and 1 kHz, the dominant source is thermal noise originating in the acoustic flow resistance of the small hole pierced in the diaphragm to equalize barometric pressure. Between approximately 1 kHz and 9 kHz, the noise originates in the acoustic flow resistances of sound entering the microphone and propagating to the diaphragm. To further reduce the microphone internal noise in the audio band requires attacking these sources. A prototype microphone having reduced acoustical noise is measured and discussed.

  4. Miniaturized Electrochemical Flow Cells

    PubMed Central

    Sahlin, Eskil; Halle, Alexandra ter; Schaefer, Kathleen; Horn, Jeffery; Then, Matthew; Weber, Stephen G.

    2006-01-01

    Several novel types of miniaturized electrochemical flow cells are described. The flow cells are fabricated in fluorinated ethylene propylene using a novel technique where channels with inner diameters down to 13 μm are integrated with electrodes. The channel is formed by shrinking and simultaneous melting of a heat shrink/melt tubing around a channel template (a tungsten wire) and electrodes followed by removal of the channel template. The technique allows incorporation of different electrode materials of different sizes. The electrode configuration consists of one or two working electrodes inside the channel and a counter electrode located in the channel outlet reservoir. Electrode configurations with different channel and working electrode sizes, different electrode materials including carbon fibers, glassy carbon rods, poly(tetrafluoroethylene)/carbon composite material, and platinum wires, and different arrangements have been assembled. Hydrodynamic voltammograms in dual-electrode (generator–collector) experiments indicate good potential control for cells with 25-μm channels, while there is some iR drop in cells with 13-μm channels. Cells prepared with a cylindrical working electrode tangent and perpendicular to a flow channel show a flow rate dependence consistent with thin-layer cell behavior. Electrode areas can be made in the range of 10−10–10−8 m2. PMID:12622401

  5. Feasibility of the membrane bioreactor process for water reclamation.

    PubMed

    Adham, S; Gagliardo, P; Boulos, L; Oppenheimer, J; Trussell, R

    2001-01-01

    The feasibility of the membrane bioreactor (MBR) process for water reclamation was studied. Process evaluation was based on the following: literature review of MBRs, worldwide survey of MBRs, and preliminary costs estimates. The literature review and the survey have shown that the MBR process offers several benefits over the conventional activated sludge process, including: smaller space and reactor requirements, better effluent water quality, disinfection, increased volumetric loading, and less sludge production. The MBR process can exist in two different configurations, one with the low-pressure membrane modules replacing the clarifier downstream the bioreactor (in series), and the second with the membranes submerged within the bioreactor. Four major companies are currently marketing MBRs while many other companies are also in the process of developing new MBRs. The MBR process operates in a considerably different range of parameters than the conventional activated sludge process. The preliminary cost evaluation has shown that the MBR process is cost competitive with other conventional wastewater treatment processes.

  6. Organic ionic salt draw solutions for osmotic membrane bioreactors.

    PubMed

    Bowden, Katie S; Achilli, Andrea; Childress, Amy E

    2012-10-01

    This investigation evaluates the use of organic ionic salt solutions as draw solutions for specific use in osmotic membrane bioreactors. Also, this investigation presents a simple method for determining the diffusion coefficient of ionic salt solutions using only a characterized membrane. A selection of organic ionic draw solutions underwent a desktop screening process before being tested in the laboratory and evaluated for performance using specific salt flux (reverse salt flux per unit water flux), biodegradation potential, and replenishment cost. Two of the salts were found to have specific salt fluxes three to six times lower than two commonly used inorganic draw solutions, NaCl and MgCl(2). All of the salts tested have organic anions with the potential to degrade in the bioreactor as a carbon source and aid in nutrient removal. Results demonstrate the potential benefits of organic ionic salt draw solutions over currently implemented inorganics in osmotic membrane bioreactor systems. PMID:22771022

  7. Miniaturized cathodic arc plasma source

    DOEpatents

    Anders, Andre; MacGill, Robert A.

    2003-04-15

    A cathodic arc plasma source has an anode formed of a plurality of spaced baffles which extend beyond the active cathode surface of the cathode. With the open baffle structure of the anode, most macroparticles pass through the gaps between the baffles and reflect off the baffles out of the plasma stream that enters a filter. Thus the anode not only has an electrical function but serves as a prefilter. The cathode has a small diameter, e.g. a rod of about 1/4 inch (6.25 mm) diameter. Thus the plasma source output is well localized, even with cathode spot movement which is limited in area, so that it effectively couples into a miniaturized filter. With a small area cathode, the material eroded from the cathode needs to be replaced to maintain plasma production. Therefore, the source includes a cathode advancement or feed mechanism coupled to cathode rod. The cathode also requires a cooling mechanism. The movable cathode rod is housed in a cooled metal shield or tube which serves as both a current conductor, thus reducing ohmic heat produced in the cathode, and as the heat sink for heat generated at or near the cathode. Cooling of the cathode housing tube is done by contact with coolant at a place remote from the active cathode surface. The source is operated in pulsed mode at relatively high currents, about 1 kA. The high arc current can also be used to operate the magnetic filter. A cathodic arc plasma deposition system using this source can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

  8. The effect of a miniature argon flow rate on the spectral characteristics of a direct current atmospheric pressure glow micro-discharge between an argon microjet and a small sized flowing liquid cathode

    NASA Astrophysics Data System (ADS)

    Jamróz, Piotr; Żyrnicki, Wiesław; Pohl, Paweł

    2012-07-01

    A stable direct current atmospheric pressure glow microdischarge (dc-μAPGD) was generated between a miniature Ar flow microjet and a small sized flowing liquid cathode. The microdischarge was operated in the open to air atmosphere. High energy species, including OH, NH, NO, N2, H, O and Ar were identified in the emission spectra of this microdischarge. Additionally, atomic lines of metals dissolved in water solutions were easily excited. The near cathode and the near anode zones of the microdischarge were investigated as a function of an Ar flow rate up to 300 sccm. The spectroscopic parameters, i.e., the excitation, the vibrational and the rotational temperatures as well as the electron number density, were determined in the near cathode and the near anode regions of the microdischarge. In the near cathode region, the rotational temperatures obtained for OH (2000-2600 K) and N2 bands (1600-1950 K) were significantly lower than the excitation temperatures of Ar (7400 K-7800 K) and H (11 000-15 500 K) atoms. Vibrational temperatures of N2, OH and NO varied from 3400 to 4000 K, from 2900 to 3400 K and from 2700 to 3000 K, respectively. In the near anode region, rotational temperatures of OH (350-1750 K) and N2 (400-1350 K) and excitation temperatures of Ar (5200-5500 K) and H (3600-12 600 K) atoms were lower than those measured in the near cathode region. The effect of the introduction of a liquid sample on the microdischarge radiation and spectroscopic parameters was also investigated in the near cathode zone. The electron number density was calculated from the Stark broadening of the Hβ line and equals to (0.25-1.1) × 1015 cm- 3 and (0.68-1.2) × 1015 cm- 3 in the near cathode and the near anode zones, respectively. The intensity of the Na I emission line and the signal to background ratio (SBR) of this line were investigated in both zones to evaluate the excitation properties of the developed excitation microsource. The limit of detection for Na was determined

  9. Miniature, Variable-Speed Control Moment Gyroscope

    NASA Technical Reports Server (NTRS)

    Bilski, Steve; Kline-Schoder, Robert; Sorensen, Paul

    2011-01-01

    The Miniature Variable-Speed Control Moment Gyroscope (MVS-CMG) was designed for small satellites (mass from less than 1 kg up to 500 kg). Currently available CMGs are too large and heavy, and available miniature CMGs do not provide sufficient control authority for use on practical satellites. This primarily results from the need to greatly increase the speed of rotation of the flywheel in order to reduce the flywheel size and mass. This goal was achieved by making use of a proprietary, space-qualified, high-speed (100,000 rpm) motor technology to spin the flywheel at a speed ten times faster than other known miniature CMGs under development. NASA is supporting innovations in propulsion, power, and guidance and navigation systems for low-cost small spacecraft. One of the key enabling technologies is attitude control mechanisms. CMGs are particularly attractive for spacecraft attitude control since they can achieve higher torques with lower mass and power than reaction wheels, and they provide continuous torque capability that enables precision pointing (in contrast to on-off thruster control). The aim of this work was to develop a miniature, variable-speed CMG that is sized for use on small satellites. To achieve improved agility, these spacecraft must be able to slew at high rate, which requires attitude control actuators that can apply torques on the order of 5 N-m. The MVS-CMG is specifically designed to achieve a high-torque output with a minimum flywheel and system mass. The flywheel can be run over a wide range of speeds, which is important to help reduce/eliminate potential gimbal lock, and can be used to optimize the operational envelope of the CMG.

  10. LEACHATE RECIRCULATION, METHANOGENS AND METAL CONCENTRATIONS IN BIOREACTOR LANDFILLS

    EPA Science Inventory

    The idea of operating landfills as bioreactors has received a lot of attention owing to many of the economic and waste treatment benefits. Portions of the Outer Loop landfill in Louisville, KY, owned and operated by WMI, Inc., are currently being used to test two different decom...

  11. Cell culture experiments planned for the space bioreactor

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.; Cross, John H.

    1987-01-01

    Culturing of cells in a pilot-scale bioreactor remains to be done in microgravity. An approach is presented based on several studies of cell culture systems. Previous and current cell culture research in microgravity which is specifically directed towards development of a space bioprocess is described. Cell culture experiments planned for a microgravity sciences mission are described in abstract form.

  12. A Scalable Perfusion Culture System with Miniature Peristaltic Pumps for Live-Cell Imaging Assays with Provision for Microfabricated Scaffolds

    PubMed Central

    Balakrishnan, Sreenath; Suma, M.S.; Raju, Shilpa R.; Bhargav, Santosh D.B.; Arunima, S.; Das, Saumitra

    2015-01-01

    Abstract We present a perfusion culture system with miniature bioreactors and peristaltic pumps. The bioreactors are designed for perfusion, live-cell imaging studies, easy incorporation of microfabricated scaffolds, and convenience of operation in standard cell culture techniques. By combining with miniature peristaltic pumps—one for each bioreactor to avoid cross-contamination and to maintain desired flow rate in each—we have made a culture system that facilitates perfusion culture inside standard incubators. This scalable system can support multiple parallel perfusion experiments. The major components are fabricated by three-dimensional printing using VeroWhite, which we show to be amenable to ex vivo cell culture. Furthermore, the components of the system can be reused, thus making it economical. We validate the system and illustrate its versatility by culturing primary rat hepatocytes, live imaging the growth of mouse fibroblasts (NIH 3T3) on microfabricated ring-scaffolds inserted into the bioreactor, performing perfusion culture of breast cancer cells (MCF7), and high-magnification imaging of hepatocarcinoma cells (HuH7). PMID:26309810

  13. Miniature Intelligent Sensor Module

    NASA Technical Reports Server (NTRS)

    Beech, Russell S.

    2007-01-01

    An electronic unit denoted the Miniature Intelligent Sensor Module performs sensor-signal-conditioning functions and local processing of sensor data. The unit includes four channels of analog input/output circuitry, a processor, volatile and nonvolatile memory, and two Ethernet communication ports, all housed in a weathertight enclosure. The unit accepts AC or DC power. The analog inputs provide programmable gain, offset, and filtering as well as shunt calibration and auto-zeroing. Analog outputs include sine, square, and triangular waves having programmable frequencies and amplitudes, as well as programmable amplitude DC. One innovative aspect of the design of this unit is the integration of a relatively powerful processor and large amount of memory along with the sensor-signalconditioning circuitry so that sophisticated computer programs can be used to acquire and analyze sensor data and estimate and track the health of the overall sensor-data-acquisition system of which the unit is a part. The unit includes calibration, zeroing, and signalfeedback circuitry to facilitate health monitoring. The processor is also integrated with programmable logic circuitry in such a manner as to simplify and enhance acquisition of data and generation of analog outputs. A notable unique feature of the unit is a cold-junction compensation circuit in the back shell of a sensor connector. This circuit makes it possible to use Ktype thermocouples without compromising a housing seal. Replicas of this unit may prove useful in industrial and manufacturing settings - especially in such large outdoor facilities as refineries. Two features can be expected to simplify installation: the weathertight housings should make it possible to mount the units near sensors, and the Ethernet communication capability of the units should facilitate establishment of communication connections for the units.

  14. Miniature EVA Software Defined Radio

    NASA Technical Reports Server (NTRS)

    Pozhidaev, Aleksey

    2012-01-01

    As NASA embarks upon developing the Next-Generation Extra Vehicular Activity (EVA) Radio for deep space exploration, the demands on EVA battery life will substantially increase. The number of modes and frequency bands required will continue to grow in order to enable efficient and complex multi-mode operations including communications, navigation, and tracking applications. Whether conducting astronaut excursions, communicating to soldiers, or first responders responding to emergency hazards, NASA has developed an innovative, affordable, miniaturized, power-efficient software defined radio that offers unprecedented power-efficient flexibility. This lightweight, programmable, S-band, multi-service, frequency- agile EVA software defined radio (SDR) supports data, telemetry, voice, and both standard and high-definition video. Features include a modular design, an easily scalable architecture, and the EVA SDR allows for both stationary and mobile battery powered handheld operations. Currently, the radio is equipped with an S-band RF section. However, its scalable architecture can accommodate multiple RF sections simultaneously to cover multiple frequency bands. The EVA SDR also supports multiple network protocols. It currently implements a Hybrid Mesh Network based on the 802.11s open standard protocol. The radio targets RF channel data rates up to 20 Mbps and can be equipped with a real-time operating system (RTOS) that can be switched off for power-aware applications. The EVA SDR's modular design permits implementation of the same hardware at all Network Nodes concept. This approach assures the portability of the same software into any radio in the system. It also brings several benefits to the entire system including reducing system maintenance, system complexity, and development cost.

  15. Space bioreactor: Design/process flow

    NASA Technical Reports Server (NTRS)

    Cross, John H.

    1987-01-01

    The design of the space bioreactor stems from three considerations. First, and foremost, it must sustain cells in microgravity. Closely related is the ability to take advantage of the weightlessness and microgravity. Lastly, it should fit into a bioprocess. The design of the space bioreactor is described in view of these considerations. A flow chart of the bioreactor is presented and discussed.

  16. Collaborating miniature drones for surveillance and reconnaissance

    NASA Astrophysics Data System (ADS)

    Bürkle, Axel

    2009-09-01

    The use of miniature Unmanned Aerial Vehicles (UAVs), e.g. quadrocopters, has gained great popularity over the last years. Some complex application scenarios for micro UAVs call for the formation of swarms of multiple drones. In this paper a platform for the creation of such swarms is presented. It consists of commercial quadrocopters enhanced with on-board processing and communication units enabling autonomy of individual drones. Furthermore, a generic ground control station has been realized. Different co-operation strategies for teams of UAVs are currently evaluated with an agent based simulation tool. Finally, complex application scenarios for multiple micro UAVs are presented.

  17. Tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Cells from kidneys lose some of their special features in conventional culture but form spheres replete with specialized cell microvilli (hair) and synthesize hormones that may be clinically useful. Ground-based research studies have demonstrated that both normal and neoplastic cells and tissues recreate many of the characteristics in the NASA bioreactor that they display in vivo. Proximal kidney tubule cells that normally have rich apically oriented microvilli with intercellular clefts in the kidney do not form any of these structures in conventional two-dimensional monolayer culture. However, when normal proximal renal tubule cells are cultured in three-dimensions in the bioreactor, both the microvilli and the intercellular clefts form. This is important because, when the morphology is recreated, the function is more likely also to be rejuvenated. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  18. Potentials and limitations of miniaturized calorimeters for bioprocess monitoring.

    PubMed

    Maskow, Thomas; Schubert, Torsten; Wolf, Antje; Buchholz, Friederike; Regestein, Lars; Buechs, Jochen; Mertens, Florian; Harms, Hauke; Lerchner, Johannes

    2011-10-01

    In theory, heat production rates are very well suited for analysing and controlling bioprocesses on different scales from a few nanolitres up to many cubic metres. Any bioconversion is accompanied by a production (exothermic) or consumption (endothermic) of heat. The heat is tightly connected with the stoichiometry of the bioprocess via the law of Hess, and its rate is connected to the kinetics of the process. Heat signals provide real-time information of bioprocesses. The combination of heat measurements with respirometry is theoretically suited for the quantification of the coupling between catabolic and anabolic reactions. Heat measurements have also practical advantages. Unlike most other biochemical sensors, thermal transducers can be mounted in a protected way that prevents fouling, thereby minimizing response drifts. Finally, calorimetry works in optically opaque solutions and does not require labelling or reactants. It is surprising to see that despite all these advantages, calorimetry has rarely been applied to monitor and control bioprocesses with intact cells in the laboratory, industrial bioreactors or ecosystems. This review article analyses the reasons for this omission, discusses the additional information calorimetry can provide in comparison with respirometry and presents miniaturization as a potential way to overcome some inherent weaknesses of conventional calorimetry. It will be discussed for which sample types and scientific question miniaturized calorimeter can be advantageously applied. A few examples from different fields of microbiological and biotechnological research will illustrate the potentials and limitations of chip calorimetry. Finally, the future of chip calorimetry is addressed in an outlook. PMID:21808971

  19. Novel Hydrogen Bioreactor and Detection Apparatus.

    PubMed

    Rollin, Joseph A; Ye, Xinhao; Del Campo, Julia Martin; Adams, Michael W W; Zhang, Y-H Percival

    2016-01-01

    In vitro hydrogen generation represents a clear opportunity for novel bioreactor and system design. Hydrogen, already a globally important commodity chemical, has the potential to become the dominant transportation fuel of the future. Technologies such as in vitro synthetic pathway biotransformation (SyPaB)-the use of more than 10 purified enzymes to catalyze unnatural catabolic pathways-enable the storage of hydrogen in the form of carbohydrates. Biohydrogen production from local carbohydrate resources offers a solution to the most pressing challenges to vehicular and bioenergy uses: small-size distributed production, minimization of CO2 emissions, and potential low cost, driven by high yield and volumetric productivity. In this study, we introduce a novel bioreactor that provides the oxygen-free gas phase necessary for enzymatic hydrogen generation while regulating temperature and reactor volume. A variety of techniques are currently used for laboratory detection of biohydrogen, but the most information is provided by a continuous low-cost hydrogen sensor. Most such systems currently use electrolysis for calibration; here an alternative method, flow calibration, is introduced. This system is further demonstrated here with the conversion of glucose to hydrogen at a high rate, and the production of hydrogen from glucose 6-phosphate at a greatly increased reaction rate, 157 mmol/L/h at 60 °C.

  20. Miniaturized Cassegrainian concentrator concept demonstration

    NASA Technical Reports Server (NTRS)

    Patterson, R. E.; Rauschenbach, H. S.

    1982-01-01

    High concentration ratio photovoltaic systems for space applications have generally been considered impractical because of perceived difficulties in controlling solar cell temperatures to reasonably low values. A miniaturized concentrator system is now under development which surmounts this objection by providing acceptable solar cell temperatures using purely passive cell cooling methods. An array of identical miniaturized, rigid Cassegrainian optical systems having a low f-number with resulting short dimensions along their optical axes are rigidly mounted into a frame to form a relatively thin concentrator solar array panel. A number of such panels, approximately 1.5 centimeters thick, are wired as an array and are folded against one another for launch in a stowed configuration. Deployment on orbit is similar to the deployment of conventional planar honeycomb panel arrays or flexible blanket arrays. The miniaturized concept was conceived and studied in the 1978-80 time frame. Progress in the feasibility demonstration to date is reported.

  1. Some process control/design considerations in the development of a microgravity mammalian cell bioreactor

    NASA Technical Reports Server (NTRS)

    Goochee, Charles F.

    1987-01-01

    The purpose is to review some of the physical/metabolic factors which must be considered in the development of an operating strategy for a mammalian cell bioreactor. Emphasis is placed on the dissolved oxygen and carbon dioxide requirements of growing mammalian epithelial cells. Literature reviews concerning oxygen and carbon dioxide requirements are discussed. A preliminary, dynamic model which encompasses the current features of the NASA bioreactor is presented. The implications of the literature survey and modeling effort on the design and operation of the NASA bioreactor are discussed.

  2. Miniature Bipolar Electrostatic Ion Thruster

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.

    2006-01-01

    The figure presents a concept of a bipolar miniature electrostatic ion thruster for maneuvering a small spacecraft. The ionization device in the proposed thruster would be a 0.1-micron-thick dielectric membrane with metal electrodes on both sides. Small conical holes would be micromachined through the membrane and electrodes. An electric potential of the order of a volt applied between the membrane electrodes would give rise to an electric field of the order of several mega-volts per meter in the submicron gap between the electrodes. An electric field of this magnitude would be sufficient to ionize all the molecules that enter the holes. In a thruster-based on this concept, one or more propellant gases would be introduced into such a membrane ionizer. Unlike in larger prior ion thrusters, all of the propellant molecules would be ionized. This thruster would be capable of bipolar operation. There would be two accelerator grids - one located forward and one located aft of the membrane ionizer. In one mode of operation, which one could denote the forward mode, positive ions leaving the ionizer on the backside would be accelerated to high momentum by an electric field between the ionizer and an accelerator grid. Electrons leaving the ionizer on the front side would be ejected into free space by a smaller accelerating field. The equality of the ion and electron currents would eliminate the need for an additional electron- or ion-emitting device to keep the spacecraft charge-neutral. In another mode of operation, which could denote the reverse mode, the polarities of the voltages applied to the accelerator grids and to the electrodes of the membrane ionizer would be the reverse of those of the forward mode. The reversal of electric fields would cause the ion and electrons to be ejected in the reverse of their forward mode directions, thereby giving rise to thrust in the direction opposite that of the forward mode.

  3. A Good Neighborhood for Cells: Bioreactor Demonstration System (BDS-05)

    NASA Technical Reports Server (NTRS)

    Chung, Leland W. K.; Goodwin, Thomas J. (Technical Monitor)

    2002-01-01

    Good neighborhoods help you grow. As with a city, the lives of a cell are governed by its neighborhood connections Connections that do not work are implicated in a range of diseases. One of those connections - between prostate cancer and bone cells - will be studied on STS-107 using the Bioreactor Demonstration System (BDS-05). To improve the prospects for finding novel therapies, and to identify biomarkers that predict disease progression, scientists need tissue models that behave the same as metastatic or spreading cancer. This is one of several NASA-sponsored lines of cell science research that use the microgravity environment of orbit in an attempt to grow lifelike tissue models for health research. As cells replicate, they "self associate" to form a complex matrix of collagens, proteins, fibers, and other structures. This highly evolved microenvironment tells each cell who is next door, how it should grow arid into what shapes, and how to respond to bacteria, wounds, and other stimuli. Studying these mechanisms outside the body is difficult because cells do not easily self-associate outside a natural environment. Most cell cultures produce thin, flat specimens that offer limited insight into how cells work together. Ironically, growing cell cultures in the microgravity of space produces cell assemblies that more closely resemble what is found in bodies on Earth. NASA's Bioreactor comprises a miniature life support system and a rotating vessel containing cell specimens in a nutrient medium. Orbital BDS experiments that cultured colon and prostate cancers have been highly promising.

  4. Use Alkalinity Monitoring to Optimize Bioreactor Performance.

    PubMed

    Jones, Christopher S; Kult, Keegan J

    2016-05-01

    In recent years, the agricultural community has reduced flow of nitrogen from farmed landscapes to stream networks through the use of woodchip denitrification bioreactors. Although deployment of this practice is becoming more common to treat high-nitrate water from agricultural drainage pipes, information about bioreactor management strategies is sparse. This study focuses on the use of water monitoring, and especially the use of alkalinity monitoring, in five Iowa woodchip bioreactors to provide insights into and to help manage bioreactor chemistry in ways that will produce desirable outcomes. Results reported here for the five bioreactors show average annual nitrate load reductions between 50 and 80%, which is acceptable according to established practice standards. Alkalinity data, however, imply that nitrous oxide formation may have regularly occurred in at least three of the bioreactors that are considered to be closed systems. Nitrous oxide measurements of influent and effluent water provide evidence that alkalinity may be an important indicator of bioreactor performance. Bioreactor chemistry can be managed by manipulation of water throughput in ways that produce adequate nitrate removal while preventing undesirable side effects. We conclude that (i) water should be retained for longer periods of time in bioreactors where nitrous oxide formation is indicated, (ii) measuring only nitrate and sulfate concentrations is insufficient for proper bioreactor operation, and (iii) alkalinity monitoring should be implemented into protocols for bioreactor management. PMID:27136151

  5. Use Alkalinity Monitoring to Optimize Bioreactor Performance.

    PubMed

    Jones, Christopher S; Kult, Keegan J

    2016-05-01

    In recent years, the agricultural community has reduced flow of nitrogen from farmed landscapes to stream networks through the use of woodchip denitrification bioreactors. Although deployment of this practice is becoming more common to treat high-nitrate water from agricultural drainage pipes, information about bioreactor management strategies is sparse. This study focuses on the use of water monitoring, and especially the use of alkalinity monitoring, in five Iowa woodchip bioreactors to provide insights into and to help manage bioreactor chemistry in ways that will produce desirable outcomes. Results reported here for the five bioreactors show average annual nitrate load reductions between 50 and 80%, which is acceptable according to established practice standards. Alkalinity data, however, imply that nitrous oxide formation may have regularly occurred in at least three of the bioreactors that are considered to be closed systems. Nitrous oxide measurements of influent and effluent water provide evidence that alkalinity may be an important indicator of bioreactor performance. Bioreactor chemistry can be managed by manipulation of water throughput in ways that produce adequate nitrate removal while preventing undesirable side effects. We conclude that (i) water should be retained for longer periods of time in bioreactors where nitrous oxide formation is indicated, (ii) measuring only nitrate and sulfate concentrations is insufficient for proper bioreactor operation, and (iii) alkalinity monitoring should be implemented into protocols for bioreactor management.

  6. Miniature Ion-Mobility Spectrometer

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.

    2006-01-01

    The figure depicts a proposed miniature ion-mobility spectrometer that would be fabricated by micromachining. Unlike prior ion-mobility spectrometers, the proposed instrument would not be based on a time-of-flight principle and, consequently, would not have some of the disadvantageous characteristics of prior time-of-flight ion-mobility spectrometers. For example, one of these characteristics is the need for a bulky carrier-gas-feeding subsystem that includes a shutter gate to provide short pulses of gas in order to generate short pulses of ions. For another example, there is need for a complex device to generate pulses of ions from the pulses of gas and the device is capable of ionizing only a fraction of the incoming gas molecules; these characteristics preclude miniaturization. In contrast, the proposed instrument would not require a carrier-gas-feeding subsystem and would include a simple, highly compact device that would ionize all the molecules passing through it. The ionization device in the proposed instrument would be a 0.1-micron-thick dielectric membrane with metal electrodes on both sides. Small conical holes would be micromachined through the membrane and electrodes. An electric potential of the order of a volt applied between the membrane electrodes would give rise to an electric field of the order of several megavolts per meter in the submicron gap between the electrodes. An electric field of this magnitude would be sufficient to ionize all the molecules that enter the holes. Ionization (but not avalanche arcing) would occur because the distance between the ionizing electrodes would be less than the mean free path of gas molecules at the operating pressure of instrument. An accelerating grid would be located inside the instrument, downstream from the ionizing membrane. The electric potential applied to this grid would be negative relative to the potential on the inside electrode of the ionizing membrane and would be of a magnitude sufficient to

  7. Two new disposable bioreactors for plant cell culture: The wave and undertow bioreactor and the slug bubble bioreactor.

    PubMed

    Terrier, Bénédicte; Courtois, Didier; Hénault, Nicolas; Cuvier, Arnaud; Bastin, Maryse; Aknin, Aziz; Dubreuil, Julien; Pétiard, Vincent

    2007-04-01

    The present article describes two novel flexible plastic-based disposable bioreactors. The first one, the WU bioreactor, is based on the principle of a wave and undertow mechanism that provides agitation while offering convenient mixing and aeration to the plant cell culture contained within the bioreactor. The second one is a high aspect ratio bubble column bioreactor, where agitation and aeration are achieved through the intermittent generation of large diameter bubbles, "Taylor-like" or "slug bubbles" (SB bioreactor). It allows an easy volume increase from a few liters to larger volumes up to several hundred liters with the use of multiple units. The cultivation of tobacco and soya cells producing isoflavones is described up to 70 and 100 L working volume for the SB bioreactor and WU bioreactor, respectively. The bioreactors being disposable and pre-sterilized before use, cleaning, sterilization, and maintenance operations are strongly reduced or eliminated. Both bioreactors represent efficient and low cost cell culture systems, applicable to various cell cultures at small and medium scale, complementary to traditional stainless-steel bioreactors.

  8. LTCC based bioreactors for cell cultivation

    NASA Astrophysics Data System (ADS)

    Bartsch, H.; Welker, T.; Welker, K.; Witte, H.; Müller, J.

    2016-01-01

    LTCC multilayers offer a wide range of structural options and flexibility of connections not available in standard thin film technology. Therefore they are considered as material base for cell culture reactors. The integration of microfluidic handling systems and features for optical and electrical capturing of indicators for cell culture growth offers the platform for an open system concept. The present paper assesses different approaches for the creation of microfluidic channels in LTCC multilayers. Basic functions required for the fluid management in bioreactors include temperature and flow control. Both features can be realized with integrated heaters and temperature sensors in LTCC multilayers. Technological conditions for the integration of such elements into bioreactors are analysed. The temperature regulation for the system makes use of NTC thermistor sensors which serve as real value input for the control of the heater. It allows the adjustment of the fluid temperature with an accuracy of 0.2 K. The tempered fluid flows through the cell culture chamber. Inside of this chamber a thick film electrode array monitors the impedance as an indicator for the growth process of 3-dimensional cell cultures. At the system output a flow sensor is arranged to monitor the continual flow. For this purpose a calorimetric sensor is implemented, and its crucial design parameters are discussed. Thus, the work presented gives an overview on the current status of LTCC based fluid management for cell culture reactors, which provides a promising base for the automation of cell culture processes.

  9. High retention membrane bioreactors: challenges and opportunities.

    PubMed

    Luo, Wenhai; Hai, Faisal I; Price, William E; Guo, Wenshan; Ngo, Hao H; Yamamoto, Kazuo; Nghiem, Long D

    2014-09-01

    Extensive research has focussed on the development of novel high retention membrane bioreactor (HR-MBR) systems for wastewater reclamation in recent years. HR-MBR integrates high rejection membrane separation with conventional biological treatment in a single step. High rejection membrane separation processes currently used in HR-MBR applications include nanofiltration, forward osmosis, and membrane distillation. In these HR-MBR systems, organic contaminants can be effectively retained, prolonging their retention time in the bioreactor and thus enhancing their biodegradation. Therefore, HR-MBR can offer a reliable and elegant solution to produce high quality effluent. However, there are several technological challenges associated with the development of HR-MBR, including salinity build-up, low permeate flux, and membrane degradation. This paper provides a critical review on these challenges and potential opportunities of HR-MBR for wastewater treatment and water reclamation, and aims to guide and inform future research on HR-MBR for fast commercialisation of this innovative technology. PMID:24996563

  10. Propagation of cold atoms along a miniature magnetic guide

    PubMed

    Key; Hughes; Rooijakkers; Sauer; Hinds; Richardson; Kazansky

    2000-02-14

    A cloud of laser-cooled 85Rb atoms is coupled through a magnetic funnel into a miniature waveguide formed by four current-carrying wires embedded in a silica fiber. The atom cloud has a approximately 100 &mgr;m radius within the fiber and propagates over cm distances. We study the coupling, propagation, and transverse distribution of atoms in the fiber, and find good agreement with theory. This prototype demonstrates the feasibility of miniature guides as a tool in the new field of integrated atom optics, leading to single-mode propagation of de Broglie waves and the possible preparation of 1D atom clouds.

  11. Visual thread quality for precision miniature mechanisms

    SciTech Connect

    Gillespie, L.K.

    1981-04-01

    Threaded features have eight visual appearance factors which can affect their function in precision miniature mechanisms. The Bendix practice in deburring, finishing, and accepting these conditions on miniature threads is described as is their impact in assemblies of precision miniature electromechanical assemblies.

  12. A Laser Interferometric Miniature Sensor

    SciTech Connect

    Carr, Dustin W., PhD.; Baldwin, Patrick C.; Milburn, Howard; Robinson, David

    2011-09-12

    This is the second year of a Phase II Small Business Innovation Research (SBIR) contract geared towards the development of a new seismic sensor. Ground-based seismic monitoring systems have proven to be very capable in identifying nuclear tests, and can provide somewhat precise information on the location and yield of the explosive device. Making these measurements, however, currently requires very expensive and bulky seismometers that are difficult to deploy in places where they are most needed. A high performance, compact device can enable rapid deployment of large scale arrays, which can in turn be used to provide higher quality data during times of critical need. The use of a laser interferometer-based device has shown considerable promise, while also presenting significant challenges. The greatest strength of this optical readout technique is the ability to decouple the mechanical design from the transducer, thus enabling a miniaturized design that is not accessible with conventional sensing techniques. However, the nonlinearity in the optical response must be accounted for in the sensor output. Previously, we had proposed using a force-feedback approach to position the sensor at a point of maximum linearity. However, it can be shown that the combined nonlinearities of the optical response and the force-feedback curve necessarily results in a significant amount of unwanted noise at low frequencies. Having realized this, we have developed a new approach that eliminates force feedback, allowing the proof mass to move freely at all times. This takes advantage of some advanced optical spatial filtering that was developed at Symphony Acoustics for other types of sensors, and was recently adapted to this work. After processing the signals in real time, the digital output of the device is intrinsically linear, and the sensor can operate at any orientation with the same level of resolution, while instantly adapting to significant changes in orientation. Ultimately, we

  13. A new microfluidic concept for parallel operated milliliter-scale stirred tank bioreactors.

    PubMed

    Gebhardt, Gabi; Hortsch, Ralf; Kaufmann, Klaus; Arnold, Matthias; Weuster-Botz, Dirk

    2011-01-01

    Parallel miniaturized stirred tank bioreactors are an efficient tool for "high-throughput bioprocess design." As most industrial bioprocesses are pH-controlled and/or are operated in a fed-batch mode, an exact scale-down of these reactions with continuous dosing of fluids into the miniaturized bioreactors is highly desirable. Here, we present the development, characterization, and application of a novel concept for a highly integrated microfluidic device for a bioreaction block with 48 parallel milliliter-scale stirred tank reactors (V = 12 mL). The device consists of an autoclavable fluidic section to dispense up to three liquids individually per reactor. The fluidic section contains 144 membrane pumps, which are magnetically driven by a clamped-on actuator section. The micropumps are designed to dose 1.6 μL per pump lift. Each micropump enables a continuous addition of liquid with a flow rate of up to 3 mL h(-1) . Viscous liquids up to a viscosity of 8.2 mPa s (corresponds to a 60% v/v glycerine solution) can be pumped without changes in the flow rates. Thus, nearly all feeding solutions can be delivered, which are commonly used in bioprocesses. The functionality of the first prototype of this microfluidic device was demonstrated by double-sided pH-controlled cultivations of Saccharomyces cerevisiae based on signals of fluorimetric sensors embedded at the bottom of the bioreactors. Furthermore, fed-batch cultivations with constant and exponential feeding profiles were successfully performed. Thus, the presented novel microfluidic device will be a useful tool for parallel and, thus, efficient optimization of controlled fed-batch bioprocesses in small-scale stirred tank bioreactors. This can help to reduce bioprocess development times drastically.

  14. Fabrication of miniaturized electrostatic deflectors using LIGA

    SciTech Connect

    Jackson, K.H.; Khan-Malek, C.; Muray, L.P.

    1997-04-01

    Miniaturized electron beam columns ({open_quotes}microcolumns{close_quotes}) have been demonstrated to be suitable candidates for scanning electron microscopy (SEM), e-beam lithography and other high resolution, low voltage applications. In the present technology, microcolumns consist of {open_quotes}selectively scaled{close_quotes} micro-sized lenses and apertures, fabricated from silicon membranes with e-beam lithography, reactive ion beam etching and other semiconductor thin-film techniques. These miniaturized electron-optical elements provide significant advantages over conventional optics in performance and ease of fabrication. Since lens aberrations scale roughly with size, it is possible to fabricate simple microcolumns with extremely high brightness sources and electrostatic objective lenses, with resolution and beam current comparable to conventional e-beam columns. Moreover since microcolumns typically operate at low voltages (1 KeV), the proximity effects encountered in e-beam lithography become negligible. For high throughput applications, batch fabrication methods may be used to build large parallel arrays of microcolumns. To date, the best reported performance with a 1 keV cold field emission cathode, is 30 nm resolution at a working distance of 2mm in a 3.5mm column. Fabrication of the microcolumn deflector and stigmator, however, have remained beyond the capabilities of conventional machining operations and semiconductor processing technology. This work examines the LIGA process as a superior alternative to fabrication of the deflectors, especially in terms of degree of miniaturization, dimensional control, placement accuracy, run-out, facet smoothness and choice of suitable materials. LIGA is a combination of deep X-ray lithography, electroplating, and injection molding processes which allow the fabrication of microstructures.

  15. A novel milliliter-scale chemostat system for parallel cultivation of microorganisms in stirred-tank bioreactors.

    PubMed

    Schmideder, Andreas; Severin, Timm Steffen; Cremer, Johannes Heinrich; Weuster-Botz, Dirk

    2015-09-20

    A pH-controlled parallel stirred-tank bioreactor system was modified for parallel continuous cultivation on a 10 mL-scale by connecting multichannel peristaltic pumps for feeding and medium removal with micro-pipes (250 μm inner diameter). Parallel chemostat processes with Escherichia coli as an example showed high reproducibility with regard to culture volume and flow rates as well as dry cell weight, dissolved oxygen concentration and pH control at steady states (n=8, coefficient of variation <5%). Reliable estimation of kinetic growth parameters of E. coli was easily achieved within one parallel experiment by preselecting ten different steady states. Scalability of milliliter-scale steady state results was demonstrated by chemostat studies with a stirred-tank bioreactor on a liter-scale. Thus, parallel and continuously operated stirred-tank bioreactors on a milliliter-scale facilitate timesaving and cost reducing steady state studies with microorganisms. The applied continuous bioreactor system overcomes the drawbacks of existing miniaturized bioreactors, like poor mass transfer and insufficient process control.

  16. Miniature spectroscopic instrumentation: Applications to biology and chemistry

    NASA Astrophysics Data System (ADS)

    Bacon, Christina P.; Mattley, Yvette; DeFrece, Ronald

    2004-01-01

    Spectroscopy is a fundamental analytical tool utilized throughout all of the sciences. For chemistry and biology alone, there are thousands of applications. In the past two decades there have been monumental advances in the miniaturization of components used in spectrophotometric systems. The key components include detector arrays, laser diodes, and fiber optics. Currently, there are numerous commercially available miniature spectrometer systems as well as discrete components that are used by researchers in designing their own systems. A comprehensive summary of current instrumentation available for the design and development of miniaturized spectroscopy applications is described, including detectors, wavelength discriminating components, light sources, and sampling assemblies. Recommendations are made for designing spectrometer systems for specific applications. Current literature is reviewed for chemical and biological applications specifically using miniaturized spectrometer systems with the focus being on ultraviolet-visible-near-infrared spectrometers. The applications include laboratory applications, environmental sensing, on-site industrial analyses, botany and ecology applications, and finally clinical and biochemical studies. Additionally, microspectrometers, two-dimensional arrays, and photonics crystals are discussed in regards to their future role in chemistry and biology applications.

  17. Miniature Neurotransmission Regulates Drosophila Synaptic Structural Maturation

    PubMed Central

    Choi, Ben Jiwon; Imlach, Wendy L.; Jiao, Wei; Wolfram, Verena; Wu, Ying; Grbic, Mark; Cela, Carolina; Baines, Richard A.; Nitabach, Michael N.; McCabe, Brian D.

    2014-01-01

    Summary Miniature neurotransmission is the transsynaptic process where single synaptic vesicles spontaneously released from presynaptic neurons induce miniature postsynaptic potentials. Since their discovery over 60 years ago, miniature events have been found at every chemical synapse studied. However, the in vivo necessity for these small-amplitude events has remained enigmatic. Here, we show that miniature neurotransmission is required for the normal structural maturation of Drosophila glutamatergic synapses in a developmental role that is not shared by evoked neurotransmission. Conversely, we find that increasing miniature events is sufficient to induce synaptic terminal growth. We show that miniature neurotransmission acts locally at terminals to regulate synapse maturation via a Trio guanine nucleotide exchange factor (GEF) and Rac1 GTPase molecular signaling pathway. Our results establish that miniature neurotransmission, a universal but often-overlooked feature of synapses, has unique and essential functions in vivo. PMID:24811381

  18. Miniature Free-Space Electrostatic Ion Thrusters

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.; Stephens, James B.

    2006-01-01

    A miniature electrostatic ion thruster is proposed for maneuvering small spacecraft. In a thruster based on this concept, one or more propellant gases would be introduced into an ionizer based on the same principles as those of the device described in an earlier article, "Miniature Bipolar Electrostatic Ion Thruster". On the front side, positive ions leaving an ionizer element would be accelerated to high momentum by an electric field between the ionizer and an accelerator grid around the periphery of the concave laminate structure. On the front side, electrons leaving an ionizer element would be ejected into free space by a smaller accelerating field. The equality of the ion and electron currents would eliminate the need for an additional electron- or ion-emitting device to keep the spacecraft charge-neutral. In a thruster design consisting of multiple membrane ionizers in a thin laminate structure with a peripheral accelerator grid, the direction of thrust could then be controlled (without need for moving parts in the thruster) by regulating the supply of gas to specific ionizer.

  19. Miniature Mass Spectrometers for Hydrogen Isotopic Analyses

    SciTech Connect

    Spencer, W.A.

    2003-05-29

    As part of the Defense Programs Plant Directed Research and Development Program, the Savannah River Technology Center investigated the emerging area of miniature mass sensors for hydrogen and hydrogen isotope analysis. New sensors from Ferran Scientific and a beta prototype sensor from Mass Sensors, Inc. were purchased. A small pumping platform was designed and assembled. Components for miniature ion traps were investigated based on design information from Oak Ridge National Laboratories. The systems were compared to a conventional residual gas analyzer based on a Stanford Research RGA 300. Each of the sensors investigated had distinct advantages for particular applications. The Ferran system was the least expensive and the smallest, but it had low resolution for hydrogen and deuterium mixtures. The Mass Sensor unit used a new ExB design which achieved excellent resolution of the hydrogen isotopes in a small package. One limitation with the current design was the small 3 to 4 order dynamic range and another was a need for a variable sampling rate to speed analysis over a wider mass range.

  20. Miniature x-ray source

    DOEpatents

    Trebes, James E.; Bell, Perry M.; Robinson, Ronald B.

    2000-01-01

    A miniature x-ray source utilizing a hot filament cathode. The source has a millimeter scale size and is capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature source consists of a compact vacuum tube assembly containing the hot filament cathode, an anode, a high voltage feedthru for delivering high voltage to the cathode, a getter for maintaining high vacuum, a connector for initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is fabricated from highly x-ray transparent materials, such as sapphire, diamond, or boron nitride.

  1. Miniature x-ray source

    DOEpatents

    Trebes, James E.; Stone, Gary F.; Bell, Perry M.; Robinson, Ronald B.; Chornenky, Victor I.

    2002-01-01

    A miniature x-ray source capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature x-ray source comprises a compact vacuum tube assembly containing a cathode, an anode, a high voltage feedthru for delivering high voltage to the anode, a getter for maintaining high vacuum, a connection for an initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is highly x-ray transparent and made, for example, from boron nitride. The compact size and potential for remote operation allows the x-ray source, for example, to be placed adjacent to a material sample undergoing analysis or in proximity to the region to be treated for medical applications.

  2. Methane production in simulated hybrid bioreactor landfill.

    PubMed

    Xu, Qiyong; Jin, Xiao; Ma, Zeyu; Tao, Huchun; Ko, Jae Hac

    2014-09-01

    The aim of this work was to study a hybrid bioreactor landfill technology for landfill methane production from municipal solid waste. Two laboratory-scale columns were operated for about ten months to simulate an anaerobic and a hybrid landfill bioreactor, respectively. Leachate was recirculated into each column but aeration was conducted in the hybrid bioreactor during the first stage. Results showed that leachate pH in the anaerobic bioreactor maintained below 6.5, while in the hybrid bioreactor quickly increased from 5.6 to 7.0 due to the aeration. The temporary aeration resulted in lowering COD and BOD5 in the leachate. The volume of methane collected from the hybrid bioreactor was 400 times greater than that of the anaerobic bioreactor. Also, the methane production rate of the hybrid bioreactor was improved within a short period of time. After about 10 months' operation, the total methane production in the hybrid bioreactor was 212 L (16 L/kgwaste).

  3. Prostate tumor grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This prostate cancer construct was grown during NASA-sponsored bioreactor studies on Earth. Cells are attached to a biodegradable plastic lattice that gives them a head start in growth. Prostate tumor cells are to be grown in a NASA-sponsored Bioreactor experiment aboard the STS-107 Research-1 mission in 2002. Dr. Leland Chung of the University of Virginia is the principal investigator. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and the University of Virginia.

  4. Monolithic Continuous-Flow Bioreactors

    NASA Technical Reports Server (NTRS)

    Stephanopoulos, Gregory; Kornfield, Julia A.; Voecks, Gerald A.

    1993-01-01

    Monolithic ceramic matrices containing many small flow passages useful as continuous-flow bioreactors. Ceramic matrix containing passages made by extruding and firing suitable ceramic. Pores in matrix provide attachment medium for film of cells and allow free movement of solution. Material one not toxic to micro-organisms grown in reactor. In reactor, liquid nutrients flow over, and liquid reaction products flow from, cell culture immobilized in one set of channels while oxygen flows to, and gaseous reaction products flow from, culture in adjacent set of passages. Cells live on inner surfaces containing flowing nutrient and in pores of walls of passages. Ready access to nutrients and oxygen in channels. They generate continuous high yield characteristic of immobilized cells, without large expenditure of energy otherwise incurred if necessary to pump nutrient solution through dense biomass as in bioreactors of other types.

  5. Review of nonconventional bioreactor technology

    SciTech Connect

    Turick, C.E.; Mcllwain, M.E.

    1993-09-01

    Biotechnology will significantly affect many industrial sectors in the future. Industrial sectors that will be affected include pharmaceutical, chemical, fuel, agricultural, and environmental remediation. Future research is needed to improve bioprocessing efficiency and cost-effectiveness in order to compete with traditional technologies. This report describes recent advances in bioprocess technologies and bioreactor designs and relates them to problems encountered in many industrial bioprocessing operations. The primary focus is directed towards increasing gas and vapor transfer for enhanced bioprocess kinetics as well as unproved by-product separation and removal. The advantages and disadvantages of various conceptual designs such as hollow-fiber, gas-phase, hyperbaric/hypobaric, and electrochemical bioreactors are also discussed. Specific applications that are intended for improved bioprocesses include coal desulfurization, coal liquefaction, soil bioremediation, biomass conversion to marketable chemicals, biomining, and biohydrometallurgy as well as bioprocessing of gases and vapors.

  6. Dynamic Single-Use Bioreactors Used in Modern Liter- and m(3)- Scale Biotechnological Processes: Engineering Characteristics and Scaling Up.

    PubMed

    Löffelholz, Christian; Kaiser, Stephan C; Kraume, Matthias; Eibl, Regine; Eibl, Dieter

    2014-01-01

    During the past 10 years, single-use bioreactors have been well accepted in modern biopharmaceutical production processes targeting high-value products. Up to now, such processes have mainly been small- or medium-scale mammalian cell culture-based seed inoculum, vaccine or antibody productions. However, recently first attempts have been made to modify existing single-use bioreactors for the cultivation of plant cells and tissue cultures, and microorganisms. This has even led to the development of new single-use bioreactor types. Moreover, due to safety issues it has become clear that single-use bioreactors are the "must have" for expanding human stem cells delivering cell therapeutics, the biopharmaceuticals of the next generation. So it comes as no surprise that numerous different dynamic single-use bioreactor types, which are suitable for a wide range of applications, already dominate the market today. Bioreactor working principles, main applications, and bioengineering data are presented in this review, based on a current overview of greater than milliliter-scale, commercially available, dynamic single-use bioreactors. The focus is on stirred versions, which are omnipresent in R&D and manufacturing, and in particular Sartorius Stedim's BIOSTAT family. Finally, we examine development trends for single-use bioreactors, after discussing proven approaches for fast scaling-up processes.

  7. Handheld interface for miniature sensors

    NASA Astrophysics Data System (ADS)

    Kedia, Sunny; Samson, Scott A.; Farmer, Andrew; Smith, Matthew C.; Fries, David; Bhansali, Shekhar

    2005-02-01

    Miniaturization of laboratory sensors has been enabled by continued evolution of technology. Field portable systems are often desired, because they reduce sample handling, provide rapid feedback capability, and enhance convenience. Fieldable sensor systems should include a method for initiating the analysis, storing and displaying the results, while consuming minimal power and being compact and portable. Low cost will allow widespread usage of these systems. In this paper, we discuss a reconfigurable Personal Data Assistant (PDA) based control and data collection system for use with miniature sensors. The system is based on the Handspring visor PDA and a custom designed motherboard, which connects directly to the PDA microprocessor. The PDA provides a convenient and low cost graphical user interface, moderate processing capability, and integrated battery power. The low power motherboard provides the voltage levels, data collection, and input/output (I/O) capabilities required by many MEMS and miniature sensors. These capabilities are relayed to connectors, where an application specific daughterboard is attached. In this paper, two applications are demonstrated. First, a handheld nucleic acid sequence-based amplification (NASBA) detection sensor consisting of a heated and optical fluorescence detection system is discussed. Second, an electrostatically actuated MEMS micro mirror controller is realized.

  8. Affordable miniaturized SAR for tactical UAV applications

    NASA Astrophysics Data System (ADS)

    Sloan, George R.; Dubbert, Dale F.

    2004-08-01

    Sandia"s fielded and experimental SAR systems are well known for their real time, high resolution imagery. Previous designs, such as the Lynx radar, have been successfully demonstrated on medium-payload UAVs, including Predator and Fire Scout. However, fielding a high performance SAR sensor on even smaller (sub-50 pound payload) UAVs will require at least a 5x reduction in size, weight, and cost. This paper gives an overview of Sandia"s system concept and roadmap for near-term SAR miniaturization. Specifically, the "miniSAR" program, which plans to demonstrate a 25 pound system with 4 inch resolution in early 2005, is detailed. Accordingly, the conceptual approach, current status, design tradeoffs, and key facilitating technologies are reviewed. Lastly, future enhancements and directions are described, such as the follow-on demonstration of a sub-20 pound version with multi-mode (SAR/GMTI) capability.

  9. Miniaturization of flight deflection measurement system

    NASA Technical Reports Server (NTRS)

    Fodale, Robert (Inventor); Hampton, Herbert R. (Inventor)

    1990-01-01

    A flight deflection measurement system is disclosed including a hybrid microchip of a receiver/decoder. The hybrid microchip decoder is mounted piggy back on the miniaturized receiver and forms an integral unit therewith. The flight deflection measurement system employing the miniaturized receiver/decoder can be used in a wind tunnel. In particular, the miniaturized receiver/decoder can be employed in a spin measurement system due to its small size and can retain already established control surface actuation functions.

  10. BIOREACTOR LANDFILLS, THEORETICAL ADVANTAGES AND RESEARCH CHALLENGES

    EPA Science Inventory

    Bioreactor landfills are municipal solid waste landfills that utilize bulk liquids in an effort to accelerate solid waste degradation. There are few potential benefits for operating a MSW landfill as a bioreactor. These include leachate treatment and management, increase in the s...

  11. BIOREACTOR DESIGN - OUTER LOOP LANDFILL, LOUISVILLE, KY

    EPA Science Inventory

    Bioreactor field demonstration projects are underway at the Outer Loop Landfill in Louisville, KY, USA. The research effort is a cooperative research effort between US EPA and Waste Management Inc. Two primary kinds of municipal waste bioreactors are under study at this site. ...

  12. Bioreactors for Plant Embryogenesis and Beyond.

    PubMed

    Fei, Liwen; Weathers, Pamela

    2016-01-01

    A variety of different bioreactors have been developed for use in initiating and cultivating somatic embryos. The various designs for embryogenesis and culture are critically evaluated here. Bioreactor optimization and operation methods are also described along with recommendations for use based on desired outcome.

  13. The stress response system of proteins: Implications for bioreactor scaleup

    NASA Technical Reports Server (NTRS)

    Goochee, Charles F.

    1988-01-01

    Animal cells face a variety of environmental stresses in large scale bioreactors, including periodic variations in shear stress and dissolved oxygen concentration. Diagnostic techniques were developed for identifying the particular sources of environmental stresses for animal cells in a given bioreactor configuration. The mechanisms by which cells cope with such stresses was examined. The individual concentrations and synthesis rates of hundreds of intracellular proteins are affected by the extracellular environment (medium composition, dissolved oxygen concentration, ph, and level of surface shear stress). Techniques are currently being developed for quantifying the synthesis rates and concentrations of the intracellular proteins which are most sensitive to environmental stress. Previous research has demonstrated that a particular set of stress response proteins are synthesized by mammalian cells in response to temperature fluctuations, dissolved oxygen deprivation, and glucose deprivation. Recently, it was demonstrated that exposure of human kidney cells to high shear stress results in expression of a completely distinct set of intracellular proteins.

  14. Food analysis: a continuous challenge for miniaturized separation techniques.

    PubMed

    Asensio-Ramos, María; Hernández-Borges, Javier; Rocco, Anna; Fanali, Salvatore

    2009-11-01

    One of the current trends of modern analytical chemistry is the miniaturization of the various tools daily used by a large number of researchers. Ultrafast separations, consumption of small amounts of both samples and reagents as well as a high sensitivity and automation are some of the most important goals desired to be achieved. For many years a large number of research laboratories and analytical instrument manufacturing companies have been investing their efforts in this field, which includes miniaturized extraction materials, sample pre-treatment procedures and separation techniques. Among the separation techniques, capillary electromigration methods (which also include CEC), microchip and nano-LC/capillary LC have received special attention. Besides their well-known advantages over other separation tools, the role of these miniaturized techniques in food analysis is still probably in an early stage. In fact, applications in this field carried out by CEC, microchip, nano-LC and capillary LC are only a few when compared with other more established procedures such as conventional GC or HPLC. The scope of this review is to gather and discuss the different applications of such miniaturized techniques in this field. Concerning CE, microchip-CE and CEC works, emphasis has been placed on articles published after January 2007.

  15. Miniaturization in x ray and gamma ray spectroscopy

    NASA Technical Reports Server (NTRS)

    Iwanczyk, Jan S.; Wang, Yuzhong J.; Bradley, James G.

    1993-01-01

    The paper presents advances in two new sensor technologies and a miniaturized associated electronics technology which, when combined, can allow for very significant miniaturization and for the reduction of weight and power consumption in x-ray and gamma-ray spectroscopy systems: (1) Mercuric iodide (HgI2) x-ray technology, which allows for the first time the construction of truly portable, high-energy resolution, non-cryogenic x-ray fluorescence (XRF) elemental analyzer systems, with parameters approaching those of laboratory quality cryogenic instruments; (2) the silicon avalanche photodiode (APD), which is a solid-state light sensitive device with internal amplification, capable of uniquely replacing the vacuum photomultiplier tube in scintillation gamma-ray spectrometer applications, and offering substantial improvements in size, ruggedness, low power operation and energy resolution; and (3) miniaturized (hybridized) low noise, low power amplification and processing electronics, which take full advantage of the favorable properties of these new sensors and allow for the design and fabrication of advanced, highly miniaturized x-ray and gamma-ray spectroscopy systems. The paper also presents experimental results and examples of spectrometric systems currently under construction. The directions for future developments are discussed.

  16. The Bama miniature swine is susceptible to experimental HEV infection

    PubMed Central

    Tang, Zi-Min; Wang, Si-Ling; Ying, Dong; Wen, Gui-Ping; Cai, Wei; Zhang, Ke; Ji, Wen-Fang; Yang, Ming; Zheng, Zi-Zheng; Xia, Ning-Shao

    2016-01-01

    The hepatitis E virus (HEV) is one of the main causes of enterically transmitted hepatitis worldwide. Although the mortality rates associated with HEV are generally low, they can be up to 28% in HEV-infected pregnant women, and the elderly are more susceptible. The reasons for this selective severity are unclear, partially because there is no suitable, easy-to-use model in which to study HEV infection. Non-human primates and standard swine have been identified as being sensitive to infection with HEV and have been used for HEV infection studies. However, studies in these animals have been limited by high housing costs and the difficulty of manipulating these animals. In the current study, we established a model of HEV infection using Bama miniature swine. The model is easy to use and is sensitive to infections with HEV genotypes 3 and 4, which are classified as zoonotic HEVs. In this model, infection of Bama miniature swine with HEV genotypes 3 and 4 caused the typical features. All Bama miniature swine that were infected with HEV genotypes 3 and 4 exhibited significant HEV viremia, shedding, anti-HEV antibody responses and partial liver inflammation. Bama miniature swine may serve as an alternative to standard swine models for the study of zoonotic HEV infection and HEV genotype specificity research. PMID:27534702

  17. The Bama miniature swine is susceptible to experimental HEV infection.

    PubMed

    Tang, Zi-Min; Wang, Si-Ling; Ying, Dong; Wen, Gui-Ping; Cai, Wei; Zhang, Ke; Ji, Wen-Fang; Yang, Ming; Zheng, Zi-Zheng; Xia, Ning-Shao

    2016-01-01

    The hepatitis E virus (HEV) is one of the main causes of enterically transmitted hepatitis worldwide. Although the mortality rates associated with HEV are generally low, they can be up to 28% in HEV-infected pregnant women, and the elderly are more susceptible. The reasons for this selective severity are unclear, partially because there is no suitable, easy-to-use model in which to study HEV infection. Non-human primates and standard swine have been identified as being sensitive to infection with HEV and have been used for HEV infection studies. However, studies in these animals have been limited by high housing costs and the difficulty of manipulating these animals. In the current study, we established a model of HEV infection using Bama miniature swine. The model is easy to use and is sensitive to infections with HEV genotypes 3 and 4, which are classified as zoonotic HEVs. In this model, infection of Bama miniature swine with HEV genotypes 3 and 4 caused the typical features. All Bama miniature swine that were infected with HEV genotypes 3 and 4 exhibited significant HEV viremia, shedding, anti-HEV antibody responses and partial liver inflammation. Bama miniature swine may serve as an alternative to standard swine models for the study of zoonotic HEV infection and HEV genotype specificity research. PMID:27534702

  18. Personal miniature electrophysiological tape recorder

    NASA Astrophysics Data System (ADS)

    Green, H.

    1981-11-01

    The use of a personal miniature electrophysiological tape recorder to measure the physiological reactions of space flight personnel to space flight stress and weightlessness is described. The Oxford Instruments Medilog recorder, a battery-powered, four-channel cassette tape recorder with 24 hour endurance is carried on the person and will record EKG, EOG, EEG, and timing and event markers. The data will give information about heart rate and morphology changes, and document adaptation to zero gravity on the part of subjects who, unlike highly trained astronauts, are more representative of the normal population than were the subjects of previous space flight studies.

  19. Personal miniature electrophysiological tape recorder

    NASA Technical Reports Server (NTRS)

    Green, H.

    1981-01-01

    The use of a personal miniature electrophysiological tape recorder to measure the physiological reactions of space flight personnel to space flight stress and weightlessness is described. The Oxford Instruments Medilog recorder, a battery-powered, four-channel cassette tape recorder with 24 hour endurance is carried on the person and will record EKG, EOG, EEG, and timing and event markers. The data will give information about heart rate and morphology changes, and document adaptation to zero gravity on the part of subjects who, unlike highly trained astronauts, are more representative of the normal population than were the subjects of previous space flight studies.

  20. Miniature Autonomous Robotic Vehicle (MARV)

    SciTech Connect

    Feddema, J.T.; Kwok, K.S.; Driessen, B.J.; Spletzer, B.L.; Weber, T.M.

    1996-12-31

    Sandia National Laboratories (SNL) has recently developed a 16 cm{sup 3} (1 in{sup 3}) autonomous robotic vehicle which is capable of tracking a single conducting wire carrying a 96 kHz signal. This vehicle was developed to assess the limiting factors in using commercial technology to build miniature autonomous vehicles. Particular attention was paid to the design of the control system to search out the wire, track it, and recover if the wire was lost. This paper describes the test vehicle and the control analysis. Presented in the paper are the vehicle model, control laws, a stability analysis, simulation studies and experimental results.

  1. A miniature remote deadweight calibrator

    NASA Astrophysics Data System (ADS)

    Supplee, Frank H., Jr.; Tcheng, Ping

    A miniature, computer-controlled, deadweight calibrator was developed to remotely calibrate a force transducer mounted in a cryogenic chamber. This simple mechanism allows automatic loading and unloading of deadweights placed onto a skin friction balance during calibrations. Equipment for the calibrator includes a specially designed set of five interlocking 200-milligram weights, a motorized lifting platform, and a controller box taking commands from a microcomputer on an IEEE interface. The computer is also used to record and reduce the calibration data and control other calibration parameters. The full-scale load for this device is 1,000 milligrams; however, the concept can be extended to accommodate other calibration ranges.

  2. Maintenance energy requirements in miniature colony dogs.

    PubMed

    Serisier, S; Weber, M; Feugier, A; Fardet, M-O; Garnier, F; Biourge, V; German, A J

    2013-05-01

    There are numerous reports of maintenance energy requirements (MER) in dogs, but little information is available about energy requirements of miniature dog breeds. In this prospective, observational, cohort study, we aimed to determine MER in dogs from a number of miniature breeds and to determine which factors were associated with it. Forty-two dogs participated in the study. MER was calculated by determining daily energy intake (EI) during a period of 196 days (28-359 days) when body weight did not change significantly (e.g. ±2% in 12 weeks). Estimated median MER was 473 kJ/kg(0.75) /day (285-766 kJ/kg(0.75) /day), that is, median 113 kcal/kg(0.75) /day (68-183 kcal/kg(0.75) /day). In the obese dogs that lost weight, median MER after weight loss was completed was 360 kJ/kg(0.75) /day (285-515 kJ/kg(0.75) /day), that is, 86 kcal/kg(0.75) /day, (68-123 kcal/kg(0.75) /day). Simple linear regression analysis suggested that three breeds (e.g. Chihuahua, p = 0.002; Yorkshire terrier, p = 0.039; dachshund, p = 0.035) had an effect on MER. In addition to breed, simple linear regression revealed that neuter status (p = 0.079) and having previously been overweight (p = 0.002) were also of significance. However, with multiple linear regression analysis, only previous overweight status (MER less in dogs previously overweight p = 0.008) and breed (MER greater in Yorkshire terriers [p = 0.029] and less in Chihuahuas [p = 0.089]) remained in the final model. This study is the first to estimate MER in dogs of miniature breeds. Although further information from pet dogs is now needed, the current work will be useful for setting energy and nutrient requirement in such dogs for the future.

  3. Oxygen mass transfer in a stirred tank bioreactor using different impeller configurations for environmental purposes.

    PubMed

    Karimi, Ali; Golbabaei, Farideh; Mehrnia, Momammad Reza; Neghab, Masoud; Mohammad, Kazem; Nikpey, Ahmad; Pourmand, Mohammad Reza

    2013-01-07

    In this study, a miniature stirred tank bioreactor was designed for treatment of waste gas containing benzene, toluene and xylene. Oxygen mass transfer characteristics for various twin and single-impeller systems were investigated for 6 configurations in a vessel with 10 cm of inner diameter and working volume of 1.77L. Three types of impellers, namely, Rushton turbine, Pitched 4blades and Pitched 2blades impellers with downward pumping have been used. Deionized water was used as a liquid phase. With respect to other independent variables such as agitation speed, aeration rate, type of sparger, number of impellers, the relative performance of these impellers was assessed by comparing the values of (KLa) as a key parameter. Based on the experimental data, empirical correlations as a function of the operational conditions have been proposed, to study the oxygen transfer rates from air bubbles generated in the bioreactor. It was shown that twin Rushton turbine configuration demonstrates superior performance (23% to 77% enhancement in KLa) compared with other impeller compositions and that sparger type has negligible effect on oxygen mass transfer rate. Agitation speeds of 400 to 800 rpm were the most efficient speeds for oxygen mass transfer in the stirred bioreactor.

  4. Oxygen mass transfer in a stirred tank bioreactor using different impeller configurations for environmental purposes.

    PubMed

    Karimi, Ali; Golbabaei, Farideh; Mehrnia, Momammad Reza; Neghab, Masoud; Mohammad, Kazem; Nikpey, Ahmad; Pourmand, Mohammad Reza

    2013-01-01

    In this study, a miniature stirred tank bioreactor was designed for treatment of waste gas containing benzene, toluene and xylene. Oxygen mass transfer characteristics for various twin and single-impeller systems were investigated for 6 configurations in a vessel with 10 cm of inner diameter and working volume of 1.77L. Three types of impellers, namely, Rushton turbine, Pitched 4blades and Pitched 2blades impellers with downward pumping have been used. Deionized water was used as a liquid phase. With respect to other independent variables such as agitation speed, aeration rate, type of sparger, number of impellers, the relative performance of these impellers was assessed by comparing the values of (KLa) as a key parameter. Based on the experimental data, empirical correlations as a function of the operational conditions have been proposed, to study the oxygen transfer rates from air bubbles generated in the bioreactor. It was shown that twin Rushton turbine configuration demonstrates superior performance (23% to 77% enhancement in KLa) compared with other impeller compositions and that sparger type has negligible effect on oxygen mass transfer rate. Agitation speeds of 400 to 800 rpm were the most efficient speeds for oxygen mass transfer in the stirred bioreactor. PMID:23369581

  5. Oxygen mass transfer in a stirred tank bioreactor using different impeller configurations for environmental purposes

    PubMed Central

    2013-01-01

    In this study, a miniature stirred tank bioreactor was designed for treatment of waste gas containing benzene, toluene and xylene. Oxygen mass transfer characteristics for various twin and single-impeller systems were investigated for 6 configurations in a vessel with 10 cm of inner diameter and working volume of 1.77L. Three types of impellers, namely, Rushton turbine, Pitched 4blades and Pitched 2blades impellers with downward pumping have been used. Deionized water was used as a liquid phase. With respect to other independent variables such as agitation speed, aeration rate, type of sparger, number of impellers, the relative performance of these impellers was assessed by comparing the values of (KLa) as a key parameter. Based on the experimental data, empirical correlations as a function of the operational conditions have been proposed, to study the oxygen transfer rates from air bubbles generated in the bioreactor. It was shown that twin Rushton turbine configuration demonstrates superior performance (23% to 77% enhancement in KLa) compared with other impeller compositions and that sparger type has negligible effect on oxygen mass transfer rate. Agitation speeds of 400 to 800 rpm were the most efficient speeds for oxygen mass transfer in the stirred bioreactor. PMID:23369581

  6. Measuring Water in Bioreactor Landfills

    NASA Astrophysics Data System (ADS)

    Han, B.; Gallagher, V. N.; Imhoff, P. T.; Yazdani, R.; Chiu, P.

    2004-12-01

    Methane is an important greenhouse gas, and landfills are the largest anthropogenic source in many developed countries. Bioreactor landfills have been proposed as one means of abating greenhouse gas emissions from landfills. Here, the decomposition of organic wastes is enhanced by the controlled addition of water or leachate to maintain optimal conditions for waste decomposition. Greenhouse gas abatement is accomplished by sequestration of photosynthetically derived carbon in wastes, CO2 offsets from energy use of waste derived gas, and mitigation of methane emission from the wastes. Maintaining optimal moisture conditions for waste degradation is perhaps the most important operational parameter in bioreactor landfills. To determine how much water is needed and where to add it, methods are required to measure water within solid waste. However, there is no reliable method that can measure moisture content simply and accurately in the heterogeneous environment typical of landfills. While well drilling and analysis of solid waste samples is sometimes used to determine moisture content, this is an expensive, time-consuming, and destructive procedure. To overcome these problems, a new technology recently developed by hydrologists for measuring water in the vadose zone --- the partitioning tracer test (PTT) --- was evaluated for measuring water in solid waste in a full-scale bioreactor landfill in Yolo County, CA. Two field tests were conducted in different regions of an aerobic bioreactor landfill, with each test measuring water in ≈ 250 ft3 of solid waste. Tracers were injected through existing tubes inserted in the landfill, and tracer breakthrough curves were measured through time from the landfill's gas collection system. Gas samples were analyzed on site using a field-portable gas chromatograph and shipped offsite for more accurate laboratory analysis. In the center of the landfill, PTT measurements indicated that the fraction of the pore space filled with water

  7. Feeding strategies enhance high cell density cultivation and protein expression in milliliter scale bioreactors.

    PubMed

    Faust, Georg; Janzen, Nils H; Bendig, Christoph; Römer, Lin; Kaufmann, Klaus; Weuster-Botz, Dirk

    2014-10-01

    Miniature bioreactors under parallel fed-batch operations are not only useful screening tools for bioprocess development but also provide a suitable basis for eventual scale-up. In this study, three feeding strategies were investigated: besides the established intermittent feeding by a liquid handler, an optimized microfluidic device and a new enzymatic release system were applied for parallel fed-batch cultivation of Escherichia coli HMS174(DE3) and BL21(DE3) strains in stirred-tank bioreactors on a 10 mL scale. Lower fluctuation in dissolved oxygen (DO) and higher optical densities were measured in fed-batch processes applying the microfluidic device or the enzymatic glucose/fructose release system (conversion of intermittently added sucrose by an invertase), but no difference in dry cell weights (DCW) were observed. With all three feeding strategies high cell densities were realized on a milliliter scale with final optical density measured at 600 nm (OD600 ) of 114-133 and final DCW concentrations of 69-70 g L(-1) . The effect of feeding strategies on the expression of two heterologous proteins was investigated. Whereas no impact was observed on the expression of the spider silk protein eADF4(C16), the fluorescence of enhanced green fluorescence protein (eGFP) was reproducibly lower, if an intermittent glucose feed was applied. Thus, the impact of feeding strategy on expression is strongly dependent on the E. coli strain and/or expressed protein. As a completely continuous feed supply is difficult to realize in miniature bioreactors, the enzymatic release approach from this study can be easily applied in all microfluidic system to reduce fluctuations of glucose supply and DO concentrations.

  8. Lightweight, Miniature Inertial Measurement System

    NASA Technical Reports Server (NTRS)

    Tang, Liang; Crassidis, Agamemnon

    2012-01-01

    A miniature, lighter-weight, and highly accurate inertial navigation system (INS) is coupled with GPS receivers to provide stable and highly accurate positioning, attitude, and inertial measurements while being subjected to highly dynamic maneuvers. In contrast to conventional methods that use extensive, groundbased, real-time tracking and control units that are expensive, large, and require excessive amounts of power to operate, this method focuses on the development of an estimator that makes use of a low-cost, miniature accelerometer array fused with traditional measurement systems and GPS. Through the use of a position tracking estimation algorithm, onboard accelerometers are numerically integrated and transformed using attitude information to obtain an estimate of position in the inertial frame. Position and velocity estimates are subject to drift due to accelerometer sensor bias and high vibration over time, and so require the integration with GPS information using a Kalman filter to provide highly accurate and reliable inertial tracking estimations. The method implemented here uses the local gravitational field vector. Upon determining the location of the local gravitational field vector relative to two consecutive sensors, the orientation of the device may then be estimated, and the attitude determined. Improved attitude estimates further enhance the inertial position estimates. The device can be powered either by batteries, or by the power source onboard its target platforms. A DB9 port provides the I/O to external systems, and the device is designed to be mounted in a waterproof case for all-weather conditions.

  9. Miniaturized neural interfaces and implants

    NASA Astrophysics Data System (ADS)

    Stieglitz, Thomas; Boretius, Tim; Ordonez, Juan; Hassler, Christina; Henle, Christian; Meier, Wolfgang; Plachta, Dennis T. T.; Schuettler, Martin

    2012-03-01

    Neural prostheses are technical systems that interface nerves to treat the symptoms of neurological diseases and to restore sensory of motor functions of the body. Success stories have been written with the cochlear implant to restore hearing, with spinal cord stimulators to treat chronic pain as well as urge incontinence, and with deep brain stimulators in patients suffering from Parkinson's disease. Highly complex neural implants for novel medical applications can be miniaturized either by means of precision mechanics technologies using known and established materials for electrodes, cables, and hermetic packages or by applying microsystems technologies. Examples for both approaches will be introduced and discussed. Electrode arrays for recording of electrocorticograms during presurgical epilepsy diagnosis have been manufactured using approved materials and a marking laser to achieve an integration density that is adequate in the context of brain machine interfaces, e.g. on the motor cortex. Microtechnologies have to be used for further miniaturization to develop polymer-based flexible and light weighted electrode arrays to interface the peripheral and central nervous system. Polyimide as substrate and insulation material will be discussed as well as several application examples for nerve interfaces like cuffs, filament like electrodes and large arrays for subdural implantation.

  10. Miniature Telerobots in Space Applications

    NASA Technical Reports Server (NTRS)

    Venema, S. C.; Hannaford, B.

    1995-01-01

    Ground controlled telerobots can be used to reduce astronaut workload while retaining much of the human capabilities of planning, execution, and error recovery for specific tasks. Miniature robots can be used for delicate and time consuming tasks such as biological experiment servicing without incurring the significant mass and power penalties associated with larger robot systems. However, questions remain regarding the technical and economic effectiveness of such mini-telerobotic systems. This paper address some of these open issues and the details of two projects which will provide some of the needed answers. The Microtrex project is a joint University of Washington/NASA project which plans on flying a miniature robot as a Space Shuttle experiment to evaluate the effects of microgravity on ground-controlled manipulation while subject to variable time-delay communications. A related project involving the University of Washington and Boeing Defense and Space will evaluate the effectiveness f using a minirobot to service biological experiments in a space station experiment 'glove-box' rack mock-up, again while subject to realistic communications constraints.

  11. Miniaturized spectral imager for Aalto-1 nanosatellite

    NASA Astrophysics Data System (ADS)

    Mannila, Rami; Näsilä, Antti; Praks, Jaan; Saari, Heikki; Antila, Jarkko

    2011-11-01

    The Aalto-1 is a 3U-cubesat project coordinated by Aalto University. The satellite, Aalto-1, will be mainly built by students as project assignments and thesis works. VTT Technical Research Centre of Finland will develop the main Earth observation payload, a miniaturized spectral imager, for the satellite. It is a novel highly miniaturized tunable filter type spectral imager. Mass of the spectral imager will be less than 400 grams, and dimensions will be approximately 80 mm x 80 mm x 45 mm. The spectral imager is based on a tunable Fabry-Pérot interferometer (FPI) accompanied by an RGB CMOS image sensor. The FPI consists of two highly reflective surfaces separated by a tunable air gap and it is based either on a microelectromechanical (MEMS) or piezo-actuated structure. The MEMS FPI is a monolithic device, i.e. it is made entirely on one substrate in a batch process, without assembling separate pieces together. The gap is adjusted by moving the upper mirror with electrostatic force. Benefits of the MEMS FPI are low mass and small size. However, large aperture (2-10 mm) MEMS FPIs are currently under development, thus it is not yet known if their performance is adequate. The piezo-actuated FPI uses three piezo-actuators and is controlled in a closed capacitive feedback loop. The drawback of the piezo-actuated FPI is its higher mass. However, it has a large aperture which enables a shorter exposure times. Selection of the FPI type will be done after thorough evaluation. Depending on the selected FPI type, the spectral resolution of the imager will be 5 - 10 nm at full width at half maximum and it will operate in the visible and/or near infrared range.

  12. 33 CFR 13.01-40 - Miniature medals and bars.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... GENERAL DECORATIONS, MEDALS, RIBBONS AND SIMILAR DEVICES Gold and Silver Lifesaving Medals, Bars, and Miniatures § 13.01-40 Miniature medals and bars. (a) Miniature Gold and Silver Lifesaving Medals and bars...

  13. 33 CFR 13.01-40 - Miniature medals and bars.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... GENERAL DECORATIONS, MEDALS, RIBBONS AND SIMILAR DEVICES Gold and Silver Lifesaving Medals, Bars, and Miniatures § 13.01-40 Miniature medals and bars. (a) Miniature Gold and Silver Lifesaving Medals and bars...

  14. 33 CFR 13.01-40 - Miniature medals and bars.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... GENERAL DECORATIONS, MEDALS, RIBBONS AND SIMILAR DEVICES Gold and Silver Lifesaving Medals, Bars, and Miniatures § 13.01-40 Miniature medals and bars. (a) Miniature Gold and Silver Lifesaving Medals and bars...

  15. 33 CFR 13.01-40 - Miniature medals and bars.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... GENERAL DECORATIONS, MEDALS, RIBBONS AND SIMILAR DEVICES Gold and Silver Lifesaving Medals, Bars, and Miniatures § 13.01-40 Miniature medals and bars. (a) Miniature Gold and Silver Lifesaving Medals and bars...

  16. 33 CFR 13.01-40 - Miniature medals and bars.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... GENERAL DECORATIONS, MEDALS, RIBBONS AND SIMILAR DEVICES Gold and Silver Lifesaving Medals, Bars, and Miniatures § 13.01-40 Miniature medals and bars. (a) Miniature Gold and Silver Lifesaving Medals and bars...

  17. Miniature reaction chamber and devices incorporating same

    DOEpatents

    Mathies, Richard A.; Woolley, Adam T.

    2000-10-17

    The present invention generally relates to miniaturized devices for carrying out and controlling chemical reactions and analyses. In particular, the present invention provides devices which have miniature temperature controlled reaction chambers for carrying out a variety of synthetic and diagnostic applications, such as PCR amplification, nucleic acid hybridization, chemical labeling, nucleic acid fragmentation and the like.

  18. Anthrax vaccine associated deaths in miniature horses.

    PubMed

    Wobeser, Bruce K

    2015-04-01

    During a widespread anthrax outbreak in Canada, miniature horses were vaccinated using a live spore anthrax vaccine. Several of these horses died from an apparent immune-mediated vasculitis temporally associated with this vaccination. During the course of the outbreak, other miniature horses from different regions with a similar vaccination history, clinical signs, and necropsy findings were found.

  19. Advanced bioreactor concepts for coal processing

    SciTech Connect

    Scott, C.D.

    1988-01-01

    The development of advanced bioreactor systems for the processing of coal should follow some basic principles. Continuous operation is preferred, with maximum bioreagent concentrations and enhanced mass transfer. Although conventional stirred-tank bioreactors will be more appropriate for some processing concepts, columnar reactors with retained bioreagents could be the system of choice for most of the applications. Serious consideration must now be given to process development of some biological coal processing concepts. Process biology and biochemistry will continue to be very important, but efficient bioreactor systems will be necessary for economic feasibility. Conventional bioreactor concepts will be useful for some applications, but columnar systems represent an innovative approach to the design of continuous bioreactors with high productivity and good operational control. Fluidized and packed beds are the most promising configurations, especially where three-phase operation is required and where interphase mass transport is a likely controlling mechanism. Although the biocatalyst must be immobilized into or onto particles to be retained in the bioreactors, this also results in a very high biocatalyst concentration without washout and a significant enhancement in bioconversion rates. The multistage nature of these types of bioreactors also contributes to higher efficiencies for many types of biocatalytic processes. 25 refs.

  20. Tissue grown in space in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, such as the culture section shown here, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. The two white circles within the tumor are part of a plastic lattice that helped the cells associate. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  1. Denitrification 'Woodchip' Bioreactors for Productive and Sustainable Agricultural Systems

    NASA Astrophysics Data System (ADS)

    Christianson, L. E.; Summerfelt, S.; Sharrer, K.; Lepine, C.; Helmers, M. J.

    2014-12-01

    Growing alarm about negative cascading effects of reactive nitrogen in the environment has led to multifaceted efforts to address elevated nitrate-nitrogen levels in water bodies worldwide. The best way to mitigate N-related impacts, such as hypoxic zones and human health concerns, is to convert nitrate to stable, non-reactive dinitrogen gas through the natural process of denitrification. This means denitrification technologies need to be one of our major strategies for tackling the grand challenge of managing human-induced changes to our global nitrogen cycle. While denitrification technologies have historically been focused on wastewater treatment, there is great interest in new lower-tech options for treating effluent and drainage water from one of our largest reactive nitrogen emitters -- agriculture. Denitrification 'woodchip' bioreactors are able to enhance this natural N-conversion via addition of a solid carbon source (e.g., woodchips) and through designs that facilitate development of anoxic conditions required for denitrification. Wood-based denitrification technologies such as woodchip bioreactors and 'sawdust' walls for groundwater have been shown to be effective at reducing nitrate loads in agricultural settings around the world. Designing these systems to be low-maintenance and to avoid removing land from agricultural production has been a primary focus of this "farmer-friendly" technology. This presentation provides a background on woodchip bioreactors including design considerations, N-removal performance, and current research worldwide. Woodchip bioreactors for the agricultural sector are an accessible new option to address society's interest in improving water quality while simultaneously allowing highly productive agricultural systems to continue to provide food in the face of increasing demand, changing global diets, and fluctuating weather.

  2. Spatial Experiment Technologies Suitable for Unreturnable Bioreactor

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Zheng, Weibo; Tong, Guanghui

    2016-07-01

    The system composition and main function of the bioreactor piggybacked on TZ cargo transport spacecraft are introduced briefly in the paper.The spatial experiment technologies which are suitable for unreturnable bioreactor are described in detail,including multi-channel liquid transportion and management,multi-type animal cells circuit testing,dynamic targets microscopic observation in situ etc..The feasibility and effectiveness of these technologies which will be used in space experiment in bioreactor are verified in tests and experiments on the ground.

  3. Development of Fundamental Technologies for Micro Bioreactors

    NASA Astrophysics Data System (ADS)

    Sato, Kiichi; Kitamori, Takehiko

    This chapter reviews the development of fundamental technologies required for microchip-based bioreactors utilizing living mammalian cells and pressure driven flow. The most important factor in the bioreactor is the cell culture. For proper cell culturing, continuous medium supply from a microfluidic channel and appropriate modification of the channel surface to accommodate cell attachment is required. Moreover, the medium flow rate should be chosen carefully, because shear stress affects cell activity. The techniques presented here could be applied to the development of micro bioreactors such as microlivers, pigment production by plant cells, and artificial insemination.

  4. Tubular membrane bioreactors for biotechnological processes.

    PubMed

    Wolff, Christoph; Beutel, Sascha; Scheper, Thomas

    2013-02-01

    This article is an overview of bioreactors using tubular membranes such as hollow fibers or ceramic capillaries for cultivation processes. This diverse group of bioreactor is described here in regard to the membrane materials used, operational modes, and configurations. The typical advantages of this kind of system such as environments with low shear stress together with high cell densities and also disadvantages like poor oxygen supply are summed up. As the usage of tubular membrane bioreactors is not restricted to a certain organism, a brief overview of various applications covering nearly all types of cells from prokaryotic to eukaryotic cells is also given here. PMID:23224587

  5. Bioreactor Technology in Cardiovascular Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Mertsching, H.; Hansmann, J.

    Cardiovascular tissue engineering is a fast evolving field of biomedical science and technology to manufacture viable blood vessels, heart valves, myocar-dial substitutes and vascularised complex tissues. In consideration of the specific role of the haemodynamics of human circulation, bioreactors are a fundamental of this field. The development of perfusion bioreactor technology is a consequence of successes in extracorporeal circulation techniques, to provide an in vitro environment mimicking in vivo conditions. The bioreactor system should enable an automatic hydrodynamic regime control. Furthermore, the systematic studies regarding the cellular responses to various mechanical and biochemical cues guarantee the viability, bio-monitoring, testing, storage and transportation of the growing tissue.

  6. Miniature mechanical transfer optical coupler

    DOEpatents

    Abel, Philip; Watterson, Carl

    2011-02-15

    A miniature mechanical transfer (MT) optical coupler ("MMTOC") for optically connecting a first plurality of optical fibers with at least one other plurality of optical fibers. The MMTOC may comprise a beam splitting element, a plurality of collimating lenses, and a plurality of alignment elements. The MMTOC may optically couple a first plurality of fibers disposed in a plurality of ferrules of a first MT connector with a second plurality of fibers disposed in a plurality of ferrules of a second MT connector and a third plurality of fibers disposed in a plurality of ferrules of a third MT connector. The beam splitting element may allow a portion of each beam of light from the first plurality of fibers to pass through to the second plurality of fibers and simultaneously reflect another portion of each beam of light from the first plurality of fibers to the third plurality of fibers.

  7. Miniature hybrid optical imaging lens

    DOEpatents

    Sitter, D.N. Jr.; Simpson, M.L.

    1997-10-21

    A miniature lens system that corrects for imaging and chromatic aberrations is disclosed, the lens system being fabricated from primarily commercially-available components. A first element at the input to a lens housing is an aperture stop. A second optical element is a refractive element with a diffractive element closely coupled to, or formed a part of, the rear surface of the refractive element. Spaced closely to the diffractive element is a baffle to limit the area of the image, and this is closely followed by a second refractive lens element to provide the final correction. The image, corrected for aberrations exits the last lens element to impinge upon a detector plane were is positioned any desired detector array. The diffractive element is fabricated according to an equation that includes, as variables, the design wavelength, the index of refraction and the radius from an optical axis of the lens system components. 2 figs.

  8. Miniature hybrid optical imaging lens

    DOEpatents

    Sitter, Jr., David N.; Simpson, Marc L.

    1997-01-01

    A miniature lens system that corrects for imaging and chromatic aberrations, the lens system being fabricated from primarily commercially-available components. A first element at the input to a lens housing is an aperture stop. A second optical element is a refractive element with a diffractive element closely coupled to, or formed a part of, the rear surface of the refractive element. Spaced closely to the diffractive element is a baffle to limit the area of the image, and this is closely followed by a second refractive lens element to provide the final correction. The image, corrected for aberrations exits the last lens element to impinge upon a detector plane were is positioned any desired detector array. The diffractive element is fabricated according to an equation that includes, as variables, the design wavelength, the index of refraction and the radius from an optical axis of the lens system components.

  9. An innovative membrane bioreactor for methane biohydroxylation.

    PubMed

    Pen, N; Soussan, L; Belleville, M-P; Sanchez, J; Charmette, C; Paolucci-Jeanjean, D

    2014-12-01

    In this study, a membrane bioreactor (MBR) was developed for efficient, safe microbial methane hydroxylation with Methylosinus trichosporium OB3b. This innovative MBR, which couples a bioreactor with two gas/liquid macroporous membrane contactors supplying the two gaseous substrates (methane and oxygen) was operated in fed-batch mode. The feasibility and the reproducibility of this new biohydroxylation process were first demonstrated. The mass transfer within this MBR was twice that observed in a batch reactor in similar conditions. The productivity reached with this MBR was 75±25mgmethanol(gdrycell)(-1)h(-1). Compared to the literature, this value is 35times higher than that obtained with the only other fed-batch membrane bioreactor reported, which was run with dense membranes, and is comparable to those obtained with bioreactors fed by bubble-spargers. However, in the latter case, an explosive gas mixture can be formed, a problem that is avoided with the MBR.

  10. Bioreactor Design for Tendon/Ligament Engineering

    PubMed Central

    Wang, Tao; Gardiner, Bruce S.; Lin, Zhen; Rubenson, Jonas; Kirk, Thomas B.; Wang, Allan; Xu, Jiake

    2013-01-01

    Tendon and ligament injury is a worldwide health problem, but the treatment options remain limited. Tendon and ligament engineering might provide an alternative tissue source for the surgical replacement of injured tendon. A bioreactor provides a controllable environment enabling the systematic study of specific biological, biochemical, and biomechanical requirements to design and manufacture engineered tendon/ligament tissue. Furthermore, the tendon/ligament bioreactor system can provide a suitable culture environment, which mimics the dynamics of the in vivo environment for tendon/ligament maturation. For clinical settings, bioreactors also have the advantages of less-contamination risk, high reproducibility of cell propagation by minimizing manual operation, and a consistent end product. In this review, we identify the key components, design preferences, and criteria that are required for the development of an ideal bioreactor for engineering tendons and ligaments. PMID:23072472

  11. Parallel operation of miniature hollow cathode discharges

    SciTech Connect

    Schoenbach, K.H.; Peterkin, F.E.; Verhappen, R.

    1994-12-31

    The pressure where hollow cathode discharges operate scales inversely with the cathode hole diameter. By reducing the size of the cathode hole to less than one millimeter, the authors were able to obtain stable operation of the hollow cathode glow discharge in air, up to ten`s of torr. The current-voltage characteristic was found to have a positive slope below approximately 5 torr. This allows the authors to operate hollow cathode discharges in parallel at these pressures without using ballast resistors for the individual discharges. In an experiment with four 0.75 mm diameter cathode holes drilled in a 0.75 mm copper plate, the authors obtained stable operation of the discharges at a threshold voltage of 380 V and a total current of 0.16 mA. The intensity of the glow from each hole tended to equalize after several hours of operation. The system was run for approximately 40 hours without evident change in performance. The stability with respect to parallel operation offers the possibility to use miniature hollow cathode discharge arrays as flat panel electron and ion sources.

  12. An innovative miniature microbial fuel cell fabricated using photolithography.

    PubMed

    Chen, You-Peng; Zhao, Yue; Qiu, Ke-Qiang; Chu, Jian; Lu, Rui; Sun, Min; Liu, Xian-Wei; Sheng, Guo-Ping; Yu, Han-Qing; Chen, Jie; Li, Wen-Jie; Liu, Gang; Tian, Yang-Chao; Xiong, Ying

    2011-02-15

    Recently microbial fuel cells (MFCs) have attracted increasing interests in both environmental and energy fields. Among the various MFC configurations, miniature microbial fuel cell (mini-MFC) has a great potential for the application in medical, communication and other areas because of its miniature volume and high output power density. In this work, a 25-μL single-chamber mini-MFC was fabricated using the photolithography technique. The plate-shaped gold anodic electrode in the mini-MFC showed a higher electrochemical activity than the stripe-shaped one. A biofilm of Shewanella oneidensis MR-1 was formed on the surface of gold electrode in this micro-liter-scale MFCs. As a result, a maximum power density of 29 mW/m(2) and a maximum current density of 2148 mA/m(2) were achieved by this single-chamber mini-MFC.

  13. Thin film bioreactors in space.

    PubMed

    Hughes-Fulford, M; Scheld, H W

    1989-01-01

    Studies from the Skylab, SL-3 and D-1 missions have demonstrated that biological organisms grown in microgravity have changes in basic cellular functions such as DNA, mRNA and protein synthesis, cytoskeleton synthesis, glucose utilization and cellular differentiation. Since microgravity could affect prokaryotic and eukaryotic cells at a subcellular and molecular level, space offers us an opportunity to learn more about basic biological systems with one important variable removed. The thin film bioreactor will facilitate the handling of fluids in microgravity, under constant temperature and will allow multiple samples of cells to be grown with variable conditions. Studies on cell cultures grown in microgravity would enable us to identify and quantify changes in basic biological function in microgravity which are needed to develop new applications of orbital research and future biotechnology.

  14. Thin film bioreactors in space

    NASA Technical Reports Server (NTRS)

    Hughes-Fulford, M.; Scheld, H. W.

    1989-01-01

    Studies from the Skylab, SL-3 and D-1 missions have demonstrated that biological organisms grown in microgravity have changes in basic cellular functions such as DNA, mRNA and protein synthesis, cytoskeleton synthesis, glucose utilization, and cellular differentiation. Since microgravity could affect prokaryotic and eukaryotic cells at a subcellular and molecular level, space offers an opportunity to learn more about basic biological systems with one inmportant variable removed. The thin film bioreactor will facilitate the handling of fluids in microgravity, under constant temperature and will allow multiple samples of cells to be grown with variable conditions. Studies on cell cultures grown in microgravity would make it possible to identify and quantify changes in basic biological function in microgravity which are needed to develop new applications of orbital research and future biotechnology.

  15. NASA Bioreactors Advance Disease Treatments

    NASA Technical Reports Server (NTRS)

    2009-01-01

    The International Space Station (ISS) is falling. This is no threat to the astronauts onboard, however, because falling is part of the ISS staying in orbit. The absence of gravity beyond the Earth s atmosphere is actually an illusion; at the ISS s orbital altitude of approximately 250 miles above the surface, the planet s gravitational pull is only 12-percent weaker than on the ground. Gravity is constantly pulling the ISS back to Earth, but the space station is also constantly traveling at nearly 18,000 miles per hour. This means that, even though the ISS is falling toward Earth, it is moving sideways fast enough to continually miss impacting the planet. The balance between the force of gravity and the ISS s motion creates a stable orbit, and the fact that the ISS and everything in it including the astronauts are falling at an equal rate creates the condition of weightlessness called microgravity. The constant falling of objects in orbit is not only an important principle in space, but it is also a key element of a revolutionary NASA technology here on Earth that may soon help cure medical ailments from heart disease to diabetes. In the mid-1980s, NASA researchers at Johnson Space Center were investigating the effects of long-term microgravity on human tissues. At the time, the Agency s shuttle fleet was grounded following the 1986 Space Shuttle Challenger disaster, and researchers had no access to the microgravity conditions of space. To provide a method for recreating such conditions on Earth, Johnson s David Wolf, Tinh Trinh, and Ray Schwarz developed that same year a horizontal, rotating device called a rotating wall bioreactor that allowed the growth of human cells in simulated weightlessness. Previously, cell cultures on Earth could only be grown two-dimensionally in Petri dishes, because gravity would cause the multiplying cells to sink within their growth medium. These cells do not look or function like real human cells, which grow three-dimensionally in

  16. Energy efficiency in membrane bioreactors.

    PubMed

    Barillon, B; Martin Ruel, S; Langlais, C; Lazarova, V

    2013-01-01

    Energy consumption remains the key factor for the optimisation of the performance of membrane bioreactors (MBRs). This paper presents the results of the detailed energy audits of six full-scale MBRs operated by Suez Environnement in France, Spain and the USA based on on-site energy measurement and analysis of plant operation parameters and treatment performance. Specific energy consumption is compared for two different MBR configurations (flat sheet and hollow fibre membranes) and for plants with different design, loads and operation parameters. The aim of this project was to understand how the energy is consumed in MBR facilities and under which operating conditions, in order to finally provide guidelines and recommended practices for optimisation of MBR operation and design to reduce energy consumption and environmental impacts.

  17. Simplified Bioreactor For Growing Mammalian Cells

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn F.

    1995-01-01

    Improved bioreactor for growing mammalian cell cultures developed. Designed to support growth of dense volumes of mammalian cells by providing ample, well-distributed flows of nutrient solution with minimal turbulence. Cells relatively delicate and, unlike bacteria, cannot withstand shear forces present in turbulent flows. Bioreactor vessel readily made in larger sizes to accommodate greater cell production quantities. Molding equipment presently used makes cylinders up to 30 centimeters long. Alternative sintered plastic techniques used to vary pore size and quantity, as necessary.

  18. Colon tumor cells grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These photos compare the results of colon carcinoma cells grown in a NASA Bioreactor flown on the STS-70 Space Shuttle in 1995 flight and ground control experiments. The cells grown in microgravity (left) have aggregated to form masses that are larger and more similar to tissue found in the body than the cells cultured on the ground (right). The principal investigator is Milburn Jessup of the University of Texas M. D. Anderson Cancer Center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: NASA and University of Texas M. D. Anderson Cancer Center.

  19. Heart tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Lisa Freed and Gordana Vunjak-Novakovic, both of the Massachusetts Institute of Technology (MIT), have taken the first steps toward engineering heart muscle tissue that could one day be used to patch damaged human hearts. Cells isolated from very young animals are attached to a three-dimensional polymer scaffold, then placed in a NASA bioreactor. The cells do not divide, but after about a week start to cornect to form a functional piece of tissue. Functionally connected heart cells that are capable of transmitting electrical signals are the goal for Freed and Vunjak-Novakovic. Electrophysiological recordings of engineered tissue show spontaneous contractions at a rate of 70 beats per minute (a), and paced contractions at rates of 80, 150, and 200 beats per minute respectively (b, c, and d). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: NASA and MIT.

  20. Heart tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Lisa Freed and Gordana Vunjak-Novakovic, both of the Massachusetts Institute of Technology (MIT), have taken the first steps toward engineering heart muscle tissue that could one day be used to patch damaged human hearts. Cells isolated from very young animals are attached to a three-dimensional polymer scaffold, then placed in a NASA bioreactor. The cells do not divide, but after about a week start to cornect to form a functional piece of tissue. Here, a transmission electron micrograph of engineered tissue shows a number of important landmarks present in functional heart tissue: (A) well-organized myofilaments (Mfl), z-lines (Z), and abundant glycogen granules (Gly); and (D) intercalcated disc (ID) and desmosomes (DES). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: MIT

  1. Plasma Structure and Behavior of Miniature Ring-Cusp Discharges

    NASA Astrophysics Data System (ADS)

    Mao, Hann-Shin

    Miniature ring-cusp ion thrusters provide a unique blend of high efficiencies and millinewton level thrust for future spacecraft. These thrusters are attractive as a primary propulsion for small satellites that require a high delta V, and as a secondary propulsion for larger spacecraft that require precision formation flying, disturbance rejection, or attitude control. To ensure desirable performance throughout the life of such missions, an advancement in the understanding of the plasma structure and behavior of miniature ring-cusp discharges is required. A research model was fabricated to provide a simplified experimental test bed for the analysis of the plasma discharge chamber of a miniature ion thruster. The plasma source allowed for spatially resolved measurements with a Langmuir probe along a meridian plane. Probe measurements yielded plasma density, electron temperature, and plasma potential data. The magnetic field strength was varied along with the discharge current to determine the plasma behavior under various conditions. The structure of the plasma properties were found to be independent of the discharge power under the proper scaling. It was concluded that weaker magnetic fields can improve the overall performance for ion thruster operation. To further analyze the experimental measurements, a framework was developed based on the magnetic field. A flux aligned coordinate system was developed to decouple the perpendicular and parallel plasma motion with respect to the magnetic field. This was done using the stream function and magnetic scalar potential. Magnetic formulae provided intuition on the field profiles dependence on magnet dimensions. The flux aligned coordinate system showed that the plasma was isopycnic along constant stream function values. This was used to develop an empirical relation suitable for estimating the spatial behavior and to determine the plasma volume and loss areas. The plasma geometry estimates were applied to a control volume

  2. Estimation of flow and transport parameters for woodchip based bioreactors: I. laboratory-scale bioreactor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In subsurface bioreactors used for tile drainage systems, carbon sources are used to facilitate denitrification. The objective of this study was to estimate hydraulic conductivity, effective porosity, dispersivity, and first-order decay coefficients for a laboratory-scale bioreactor with woodchips a...

  3. Hydrodynamics of an Electrochemical Membrane Bioreactor

    PubMed Central

    Wang, Ya-Zhou; Wang, Yun-Kun; He, Chuan-Shu; Yang, Hou-Yun; Sheng, Guo-Ping; Shen, Jin-You; Mu, Yang; Yu, Han-Qing

    2015-01-01

    An electrochemical membrane bioreactor (EMBR) has recently been developed for energy recovery and wastewater treatment. The hydrodynamics of the EMBR would significantly affect the mass transfers and reaction kinetics, exerting a pronounced effect on reactor performance. However, only scarce information is available to date. In this study, the hydrodynamic characteristics of the EMBR were investigated through various approaches. Tracer tests were adopted to generate residence time distribution curves at various hydraulic residence times, and three hydraulic models were developed to simulate the results of tracer studies. In addition, the detailed flow patterns of the EMBR were acquired from a computational fluid dynamics (CFD) simulation. Compared to the tank-in-series and axial dispersion ones, the Martin model could describe hydraulic performance of the EBMR better. CFD simulation results clearly indicated the existence of a preferential or circuitous flow in the EMBR. Moreover, the possible locations of dead zones in the EMBR were visualized through the CFD simulation. Based on these results, the relationship between the reactor performance and the hydrodynamics of EMBR was further elucidated relative to the current generation. The results of this study would benefit the design, operation and optimization of the EMBR for simultaneous energy recovery and wastewater treatment. PMID:25997399

  4. Hydrodynamics of an Electrochemical Membrane Bioreactor

    NASA Astrophysics Data System (ADS)

    Wang, Ya-Zhou; Wang, Yun-Kun; He, Chuan-Shu; Yang, Hou-Yun; Sheng, Guo-Ping; Shen, Jin-You; Mu, Yang; Yu, Han-Qing

    2015-05-01

    An electrochemical membrane bioreactor (EMBR) has recently been developed for energy recovery and wastewater treatment. The hydrodynamics of the EMBR would significantly affect the mass transfers and reaction kinetics, exerting a pronounced effect on reactor performance. However, only scarce information is available to date. In this study, the hydrodynamic characteristics of the EMBR were investigated through various approaches. Tracer tests were adopted to generate residence time distribution curves at various hydraulic residence times, and three hydraulic models were developed to simulate the results of tracer studies. In addition, the detailed flow patterns of the EMBR were acquired from a computational fluid dynamics (CFD) simulation. Compared to the tank-in-series and axial dispersion ones, the Martin model could describe hydraulic performance of the EBMR better. CFD simulation results clearly indicated the existence of a preferential or circuitous flow in the EMBR. Moreover, the possible locations of dead zones in the EMBR were visualized through the CFD simulation. Based on these results, the relationship between the reactor performance and the hydrodynamics of EMBR was further elucidated relative to the current generation. The results of this study would benefit the design, operation and optimization of the EMBR for simultaneous energy recovery and wastewater treatment.

  5. Scanning Miniature Microscopes without Lenses

    NASA Technical Reports Server (NTRS)

    Wang, Yu

    2009-01-01

    The figure schematically depicts some alternative designs of proposed compact, lightweight optoelectronic microscopes that would contain no lenses and would generate magnified video images of specimens. Microscopes of this type were described previously in Miniature Microscope Without Lenses (NPO - 20218), NASA Tech Briefs, Vol. 22, No. 8 (August 1998), page 43 and Reflective Variants of Miniature Microscope Without Lenses (NPO 20610), NASA Tech Briefs, Vol. 26, No. 9 (September 1999), page 6a. To recapitulate: In the design and construction of a microscope of this type, the focusing optics of a conventional microscope are replaced by a combination of a microchannel filter and a charge-coupled-device (CCD) image detector. Elimination of focusing optics reduces the size and weight of the instrument and eliminates the need for the time-consuming focusing operation. The microscopes described in the cited prior articles contained two-dimensional CCDs registered with two-dimensional arrays of microchannels and, as such, were designed to produce full two-dimensional images, without need for scanning. The microscopes of the present proposal would contain one-dimensional (line image) CCDs registered with linear arrays of microchannels. In the operation of such a microscope, one would scan a specimen along a line perpendicular to the array axis (in other words, one would scan in pushbroom fashion). One could then synthesize a full two-dimensional image of the specimen from the line-image data acquired at one-pixel increments of position along the scan. In one of the proposed microscopes, a beam of unpolarized light for illuminating the specimen would enter from the side. This light would be reflected down onto the specimen by a nonpolarizing beam splitter attached to the microchannels at their lower ends. A portion of the light incident on the specimen would be reflected upward, through the beam splitter and along the microchannels, to form an image on the CCD. If the

  6. Advanced microscale bioreactor system: a representative scale-down model for bench-top bioreactors.

    PubMed

    Hsu, Wei-Ting; Aulakh, Rigzen P S; Traul, Donald L; Yuk, Inn H

    2012-12-01

    In recent years, several automated scale-down bioreactor systems have been developed to increase efficiency in cell culture process development. ambr™ is an automated workstation that provides individual monitoring and control of culture dissolved oxygen and pH in single-use, stirred-tank bioreactors at a working volume of 10-15 mL. To evaluate the ambr™ system, we compared the performance of four recombinant Chinese hamster ovary cell lines in a fed-batch process in parallel ambr™, 2-L bench-top bioreactors, and shake flasks. Cultures in ambr™ matched 2-L bioreactors in controlling the environment (temperature, dissolved oxygen, and pH) and in culture performance (growth, viability, glucose, lactate, Na(+), osmolality, titer, and product quality). However, cultures in shake flasks did not show comparable performance to the ambr™ and 2-L bioreactors.

  7. Metal diaphragm used to calibrate miniature transducers

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Dynamic comparative calibration system measures response of miniature pressure transducers. The system is composed of an electromechanically driven metal diaphragm, a calibrated and an uncalibrated transducer and an oscillator.

  8. Using Miniature Landforms in Teaching Geomorphology.

    ERIC Educational Resources Information Center

    Petersen, James F.

    1986-01-01

    This paper explores the uses of true landform miniatures and small-scale analogues and suggests ways to teach geomorphological concepts using small-scale relief features as illustrative examples. (JDH)

  9. Miniature infrared data acquisition and telemetry system

    NASA Technical Reports Server (NTRS)

    Stokes, J. H.; Ward, S. M.

    1985-01-01

    The Miniature Infrared Data Acquisition and Telemetry (MIRDAT) Phase 1 study was performed to determine the technical and commercial feasibility of producing a miniaturized electro-optical telemetry system. This system acquires and transmits experimental data from aircraft scale models for realtime monitoring in wind tunnels. During the Phase 1 study, miniature prototype MIRDAT telemetry devices were constructed, successfully tested in the laboratory and delivered to the user for wind tunnel testing. A search was conducted for commercially available components and advanced hybrid techniques to further miniaturize the system during Phase 2 development. A design specification was generated from laboratory testing, user requirements and discussions with component manufacturers. Finally, a preliminary design of the proposed MIRDAT system was documented for Phase 2 development.

  10. Membrane Distillation Bioreactor (MDBR) - A lower Green-House-Gas (GHG) option for industrial wastewater reclamation.

    PubMed

    Goh, Shuwen; Zhang, Jinsong; Liu, Yu; Fane, Anthony G

    2015-12-01

    A high-retention membrane bioreactor system, the Membrane Distillation Bioreactor (MDBR) is a wastewater reclamation process which has the potential to tap on waste heat generated in industries to produce high quality product water. There are a few key factors which could make MDBR an attractive advanced treatment option, namely tightening legal requirements due to increasing concerns on the micropollutants in industrial wastewater effluents as well as concerns over the electrical requirement of pressurized advanced treatment processes and greenhouse gas emissions associated with wastewater reclamation. This paper aims to provide a consolidated review on the current state of research for the MDBR system and to evaluate the system as a possible lower Green House Gas (GHG) emission option for wastewater reclamation using the membrane bioreactor-reverse osmosis (MBR-RO) system as a baseline for comparison. The areas for potential applications and possible configurations for MDBR applications are discussed. PMID:25262945

  11. Membrane Distillation Bioreactor (MDBR) - A lower Green-House-Gas (GHG) option for industrial wastewater reclamation.

    PubMed

    Goh, Shuwen; Zhang, Jinsong; Liu, Yu; Fane, Anthony G

    2015-12-01

    A high-retention membrane bioreactor system, the Membrane Distillation Bioreactor (MDBR) is a wastewater reclamation process which has the potential to tap on waste heat generated in industries to produce high quality product water. There are a few key factors which could make MDBR an attractive advanced treatment option, namely tightening legal requirements due to increasing concerns on the micropollutants in industrial wastewater effluents as well as concerns over the electrical requirement of pressurized advanced treatment processes and greenhouse gas emissions associated with wastewater reclamation. This paper aims to provide a consolidated review on the current state of research for the MDBR system and to evaluate the system as a possible lower Green House Gas (GHG) emission option for wastewater reclamation using the membrane bioreactor-reverse osmosis (MBR-RO) system as a baseline for comparison. The areas for potential applications and possible configurations for MDBR applications are discussed.

  12. Comparing the value of bioproducts from different stages of anaerobic membrane bioreactors.

    PubMed

    Khan, M A; Ngo, H H; Guo, W S; Liu, Y W; Zhou, J L; Zhang, J; Liang, S; Ni, B J; Zhang, X B; Wang, J

    2016-08-01

    The anaerobic digestion process in anaerobic membrane bioreactors is an effective way for waste management, energy sustainability and pollution control in the environment. This digestion process basically involves the production of volatile fatty acids and biohydrogen as intermediate products and methane as a final product. This paper compares the value of bioproducts from different stages of anaerobic membrane bioreactors through a thorough assessment. The value was assessed in terms of technical feasibility, economic assessment, environmental impact and impact on society. Even though the current research objective is more inclined to optimize the production of methane, the intermediate products could also be considered as economically attractive and environment friendly options. Hence, this is the first review study to correlate the idea into an anaerobic membrane bioreactor which is expected to guide future research pathways regarding anaerobic process and its bioproducts. PMID:27233838

  13. Engineering cellulosic bioreactors by template assisted DNA shuffling and in vitro recombination (TADSir).

    PubMed

    Davis, Leroy K

    2014-10-01

    The current study focuses on development of a bioreactor engineering strategy based on exploitation of the Arabidopsis thaliana genome. Chimeric A. thaliana glycosyl hydrolase (GH) gene libraries were assembled using a novel directed evolution strategy (TADSir: template assisted DNA shuffling and in vitro recombination) that promotes DNA recombination by reassembly of DNA fragments on unique gene templates. TADSir was modeled using a set of algorithms designed to simulate DNA interactions based on nearest neighbor base stacking interactions and Gibb's free energy differences between helical coil and folded DNA states. The algorithms allow for target gene prediction and for in silica analysis of chimeric gene library composition. Further, the study investigated utilization of A. thaliana GH sequence space for bioreactor design by evolving 20 A. thaliana genes representing the GH1, GH3, GH5, GH9 and GH10 gene families. Notably, TADSir achieved streamlined engineering of Saccharomyces cerevisiae and spinach mesophyll protoplast bioreactors capable of processing CM cellulose, Avicel and xylan.

  14. Comparing the value of bioproducts from different stages of anaerobic membrane bioreactors.

    PubMed

    Khan, M A; Ngo, H H; Guo, W S; Liu, Y W; Zhou, J L; Zhang, J; Liang, S; Ni, B J; Zhang, X B; Wang, J

    2016-08-01

    The anaerobic digestion process in anaerobic membrane bioreactors is an effective way for waste management, energy sustainability and pollution control in the environment. This digestion process basically involves the production of volatile fatty acids and biohydrogen as intermediate products and methane as a final product. This paper compares the value of bioproducts from different stages of anaerobic membrane bioreactors through a thorough assessment. The value was assessed in terms of technical feasibility, economic assessment, environmental impact and impact on society. Even though the current research objective is more inclined to optimize the production of methane, the intermediate products could also be considered as economically attractive and environment friendly options. Hence, this is the first review study to correlate the idea into an anaerobic membrane bioreactor which is expected to guide future research pathways regarding anaerobic process and its bioproducts.

  15. Miniaturized GPS/MEMS IMU integrated board

    NASA Technical Reports Server (NTRS)

    Lin, Ching-Fang (Inventor)

    2012-01-01

    This invention documents the efforts on the research and development of a miniaturized GPS/MEMS IMU integrated navigation system. A miniaturized GPS/MEMS IMU integrated navigation system is presented; Laser Dynamic Range Imager (LDRI) based alignment algorithm for space applications is discussed. Two navigation cameras are also included to measure the range and range rate which can be integrated into the GPS/MEMS IMU system to enhance the navigation solution.

  16. Miniature Electrostatic Ion Thruster With Magnet

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.

    2006-01-01

    A miniature electrostatic ion thruster is proposed that, with one exception, would be based on the same principles as those of the device described in the previous article, "Miniature Bipolar Electrostatic Ion Thruster". The exceptional feature of this thruster would be that, in addition to using electric fields for linear acceleration of ions and electrons, it would use a magnetic field to rotationally accelerate slow electrons into the ion stream to neutralize the ions.

  17. Miniature curved artificial compound eyes

    PubMed Central

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L’Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A.; Franceschini, Nicolas

    2013-01-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories. PMID:23690574

  18. Miniature curved artificial compound eyes.

    PubMed

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L'Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A; Franceschini, Nicolas

    2013-06-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories. PMID:23690574

  19. Miniature curved artificial compound eyes.

    PubMed

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L'Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A; Franceschini, Nicolas

    2013-06-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories.

  20. Miniature electrically operated diaphragm valve

    DOEpatents

    Adkins, Douglas R.; Spletzer, Barry L.; Wong, Chungnin C.; Frye-Mason, Gregory C.; Fischer, Gary J.; Hesketh, Peter J.

    2001-01-01

    The present invention provides a miniature electrically operated valve that can stand off significant pressures, that can be inexpensively produced, and that can be made to operate without continuous electrical power. A valve according to the present invention comprises a housing and a beam mounted with the housing. A diaphragm mounted with the housing forms a sealed fluid volume. An electromagnetic energy source, such as an electromagnetic coil, mounts with the housing and when energized urges the beam in one direction. The beam can be urged in the opposing direction by passive means or by reversing the polarity of the electromagnetic energy source or by a second electromagnetic energy source. Two fluid ports mount with the housing. A first fluid port mounts so that, as the beam is urged in one direction or the opposite, the beam urges the diaphragm to move between engaging and substantially sealing the fluid port and disengaging and not substantially sealing the fluid port. A seat can be mounted with the diaphragm to aid in sealing the fluid port. Latching mechanisms such as permanent magnets can be mounted so that the valve remains in the open or closed positions without continuous electrical power input. Fluid can flow through the housing between the two fluid ports when the diaphragm does not seal the first fluid port, but can be prevented from flowing by urging the beam so that the diaphragm seals the first fluid port. Various embodiments accommodate various latching mechanisms, electromagnetic energy sources, number of fluid ports, and diaphragm design considerations.

  1. Novel approaches to the construction of miniaturized analytical instrumentation

    NASA Technical Reports Server (NTRS)

    Porter, Marc D.; Otoole, Ronald P.; Coldiron, Shelley J.; Deninger, William D.; Deinhammer, Randall S.; Burns, Stanley G.; Bastiaans, Glenn J.; Braymen, Steve D.; Shanks, Howard R.

    1992-01-01

    This paper focuses on the design, construction, preliminary testing, and potential applications of three forms of miniaturized analytical instrumentation. The first is an optical fiber instrument for monitoring pH and other cations in aqueous solutions. The instrument couples chemically selective indicators that were immobilized at porous polymeric films with a hardware package that provides the excitation light source, required optical components, and detection and data processing hardware. The second is a new form of a piezoelectric mass sensor. The sensor was fabricated by the deposition of a thin (5.5 micron) film of piezoelectric aluminum nitride (AIN). The completed deposition process yields a thin film resonator (TFR) that is shaped as a 400 micron square and supports a standing bulk acoustic wave in a longitudinal mode at frequencies of approx. 1 GHz. Various deposition and vapor sorption studies indicate that the mass sensitivity of the TFR's rival those of the most sensitive mass sensors currently available, though offering such performance in a markedly smaller device. The third couples a novel form of liquid chromatography with microlithographic miniaturization techniques. The status of the miniaturization effort, the goal of which is to achieve chip-scale separations, is briefly discussed.

  2. Development of thermoelectric fibers for miniature thermoelectric devices

    DOE PAGESBeta

    Ren, Fei; Menchhofer, Paul A.; Kiggans, Jr., James O.; Wang, Hsin

    2016-09-23

    Miniature thermoelectric (TE) devices may be used in a variety of applications such as power sources of small sensors, temperature regulation of precision electronics, etc. Reducing the size of TE elements may also enable design of novel devices with unique form factor and higher device efficiency. Current industrial practice of fabricating TE devices usually involves mechanical removal processes that not only lead to material loss but also limit the geometry of the TE elements. In this project, we explored a powder-processing method for the fabrication of TE fibers with large length-to-area ratio, which could be potentially used for miniature TEmore » devices. Powders were milled from Bi2Te3-based bulk materials and then mixed with a thermoplastic resin dissolved in an organic solvent. Through an extrusion process, flexible, continuous fibers with sub-millimeter diameters were formed. The polymer phase was then removed by sintering. Sintered fibers exhibited similar Seebeck coefficients to the bulk materials. Moreover, their electrical resistivity was much higher, which might be related to the residual porosity and grain boundary contamination. Prototype miniature uni-couples fabricated from these fibers showed a linear I-V behavior and could generate millivolt voltages and output power in the nano-watt range. Further development of these TE fibers requires improvement in their electrical conductivities, which needs a better understanding of the causes that lead to the low conductivity in the sintered fibers.« less

  3. Development of Thermoelectric Fibers for Miniature Thermoelectric Devices

    NASA Astrophysics Data System (ADS)

    Ren, Fei; Menchhofer, Paul; Kiggans, James; Wang, Hsin

    2016-03-01

    Miniature thermoelectric (TE) devices may be used in a variety of applications such as power sources of small sensors, temperature regulation of precision electronics, etc. Reducing the size of TE elements may also enable design of novel devices with unique form factor and higher device efficiency. Current industrial practice of fabricating TE devices usually involves mechanical removal processes that not only lead to material loss but also limit the geometry of the TE elements. In this project, we explored a powder-processing method for the fabrication of TE fibers with large length-to-area ratio, which could be potentially used for miniature TE devices. Powders were milled from Bi2Te3-based bulk materials and then mixed with a thermoplastic resin dissolved in an organic solvent. Through an extrusion process, flexible, continuous fibers with sub-millimeter diameters were formed. The polymer phase was then removed by sintering. Sintered fibers exhibited similar Seebeck coefficients to the bulk materials. However, their electrical resistivity was much higher, which might be related to the residual porosity and grain boundary contamination. Prototype miniature uni-couples fabricated from these fibers showed a linear I- V behavior and could generate millivolt voltages and output power in the nano-watt range. Further development of these TE fibers requires improvement in their electrical conductivities, which needs a better understanding of the causes that lead to the low conductivity in the sintered fibers.

  4. Recent Advances in Miniaturized Optical Gyroscopes

    NASA Astrophysics Data System (ADS)

    Dell'Olio, F.; Tatoli, T.; Ciminelli, C.; Armenise, M. N.

    2014-03-01

    Low-cost chip-scale optoelectronic gyroscopes having a resolution ≤ 10 °/h and a good reliability also in harsh environments could have a strong impact on the medium/high performance gyro market, which is currently dominated by well-established bulk optical angular velocity sensors. The R&D activity aiming at the demonstration of those miniaturized sensors is crucial for aerospace/defense industry, and thus it is attracting an increasing research effort and notably funds. In this paper the recent technological advances on the compact optoelectronic gyroscopes with low weight and high energy saving are reviewed. Attention is paid to both the so-called gyroscope-on-a-chip, which is a novel sensor, at the infantile stage, whose optical components are monolithically integrated on a single indium phosphide chip, and to a new ultra-high Q ring resonator for gyro applications with a configuration including a 1D photonic crystal in the resonant path. The emerging field of the gyros based on passive ring cavities, which have already shown performance comparable with that of optical fiber gyros, is also discussed.

  5. Miniaturized Amperometric Solid Electrolyte Carbon Dioxide Sensors

    NASA Technical Reports Server (NTRS)

    Hunter, G. W.; Xu, J. C.; Liu, C. C.; Hammond, J. W.; Ward, B.; Lukco, D.; Lampard, P.; Artale, M.; Androjna, D.

    2006-01-01

    A miniaturized electrochemical carbon dioxide (CO2) sensor using Na3Z r2Si2PO12 (NASICON) as a solid electrolyte has been fabricated and de monstrated. Microfabrication techniques were used for sensor fabricat ion to yield a sensing area around 1.0 mm x 1.1 mm. The NASICON solid electrolyte and the Na2CO3/BaCO3 (1:1.7 molar ratio) auxiliary elect rolyte were deposited by sputtering in between and on top of the inte rdigitated finger-shaped platinum electrodes. This structure maximize s the length of the three-phase boundary (electrode, solid electrolyt e, and auxiliary electrolyte), which is critical for gas sensing. The robust CO2 sensor operated up to 600 C in an amperometric mode and a ttempts were made to optimize sensor operating parameters. Concentrat ions of CO2 between 0.02% and 4% were detected and the overall sensor performance was evaluated. Linear response of sensor current output to ln[CO2 concentration] ranging from 0.02% to 1% was achieved.

  6. NASA Ultra-Sensitive Miniature Accelerometer

    NASA Technical Reports Server (NTRS)

    Zavracky, Paul M.; Hartley, Frank T.

    1994-01-01

    Using micro-machined silicon technology, an ultra-sensitive miniature acce.,rometer can be constructed which meets the requirements for microgravity experiments in the space environment.Such an accelerometer will have a full scale sensitivity of 1C2 g a resolution of lC8 g, low cross axis sensitivity, and low temperature sensitivity. Mass of the device is approximately five grams and its footprint is 2 cm x 2 cm. Innovative features of the accelerometer, which are patented, are: electrostatic caging to withstand handling shock up to 150 g, in-situ calibration, in situ performance characterization, and both static and dynamic compensation. The transducer operates on a force balance principle wherein the displacement of the proof mass is monitored by measuring tunneling electron current flow between a conductive tip, and a fixed platen. The four major parts of the accelerometer are tip die, incorporating the tunneling tip and four field plates for controlling pitch and roll of the proof mass; two proof mass dies, attached to the surrounding frame by sets of four leg" springs; and a force plate die. The four parts are fuse-bonded into a complete assembly. External electrical connections are made at bond pads on the front surface of the force plate die. Materials and processes used in the construction of the transducer are compatible with volume production.

  7. Miniaturized Airborne Imaging Central Server System

    NASA Technical Reports Server (NTRS)

    Sun, Xiuhong

    2011-01-01

    data organization, fast aerial imaging applications, including the real time LWIR image mosaic for Google Earth, have been realized for NASA fs LWIR QWIP instrument. MAICSS is a significant improvement and miniaturization of current multisensor technologies. Structurally, it has a complete modular and solid-state design. Without rotating hard drives and other moving parts, it is operational at high altitudes and survivable in high-vibration environments. It is assembled from a suite of miniaturized, precision-machined, standardized, and stackable interchangeable embedded instrument modules. These stackable modules can be bolted together with the interconnection wires inside for the maximal simplicity and portability. Multiple modules are electronically interconnected as stacked. Alternatively, these dedicated modules can be flexibly distributed to fit the space constraints of a flying vehicle. As a flexibly configurable system, MAICSS can be tailored to interface a variety of multisensor packages. For example, with a 1,024x1,024 pixel LWIR and a 8,984x6,732 pixel EO payload, the complete MAICSS volume is approximately 7x9x11 in. (=18x23x28 cm), with a weight of 25 lb (=11.4 kg).

  8. Open source software to control Bioflo bioreactors.

    PubMed

    Burdge, David A; Libourel, Igor G L

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW. PMID:24667828

  9. Open source software to control Bioflo bioreactors.

    PubMed

    Burdge, David A; Libourel, Igor G L

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW.

  10. Open Source Software to Control Bioflo Bioreactors

    PubMed Central

    Burdge, David A.; Libourel, Igor G. L.

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW. PMID:24667828

  11. Nitrogen management in bioreactor landfills

    SciTech Connect

    Price, G. Alexander; Barlaz, Morton A.; Hater, Gary R

    2003-07-01

    One scenario for long-term nitrogen management in landfills is ex situ nitrification followed by denitrification in the landfill. The objective of this research was to measure the denitrification potential of actively decomposing and well decomposed refuse. A series of 10-l reactors that were actively producing methane were fed 400 mg NO{sub 3}-N /l every 48 h for periods of 19-59 days. Up to 29 nitrate additions were either completely or largely depleted within 48 h of addition and the denitrification reactions did not adversely affect the leachate pH. Nitrate did inhibit methane production, but the reactors recovered their methane-producing activity with the termination of nitrate addition. In well decomposed refuse, the nitrate consumption rate was reduced but was easily stimulated by the addition of either acetate or an overlayer of fresh refuse. Addition of acetate at five times the amount required to reduce nitrate did not lead to the production of NH{sub 4}{sup +} by dissimilatory nitrate reduction. The most probable number of denitrifying bacteria decreased by about five orders of magnitude during refuse decomposition in a reactor that did not receive nitrate. However, rapid denitrification commenced immediately with nitrate addition. This study shows that the use of a landfill as a bioreactor for the conversion of nitrate to a harmless byproduct, nitrogen gas, is technically viable.

  12. Design and Use of a Novel Bioreactor for Regeneration of Biaxially Stretched Tissue-Engineered Vessels.

    PubMed

    Huang, Angela Hai; Lee, Yong-Ung; Calle, Elizabeth A; Boyle, Michael; Starcher, Barry C; Humphrey, Jay D; Niklason, Laura E

    2015-08-01

    Conventional bioreactors are used to enhance extracellular matrix (ECM) production and mechanical strength of tissue-engineered vessels (TEVs) by applying circumferential strain, which is uniaxial stretching. However, the resulting TEVs still suffer from inadequate mechanical properties, where rupture strengths and compliance values are still very different from native arteries. The biomechanical milieu of native arteries consists of both circumferential and axial loading. Therefore, to better simulate the physiological stresses acting on native arteries, we built a novel bioreactor system to enable biaxial stretching of engineered arteries during culture. This new bioreactor system allows for independent control of circumferential and axial stretching parameters, such as displacement and beat rate. The assembly and setup processes for this biaxial bioreactor system are reliable with a success rate greater than 75% for completion of long-term sterile culture. This bioreactor also supports side-by-side assessments of TEVs that are cultured under three types of mechanical conditions (static, uniaxial, and biaxial), all within the same biochemical environment. Using this bioreactor, we examined the impact of biaxial stretching on arterial wall remodeling of TEVs. Biaxial TEVs developed the greatest wall thickness compared with static and uniaxial TEVs. Unlike uniaxial loading, biaxial loading led to undulated collagen fibers that are commonly found in native arteries. More importantly, the biaxial TEVs developed the most mature elastin in the ECM, both qualitatively and quantitatively. The presence of mature extracellular elastin along with the undulated collagen fibers may contribute to the observed vascular compliance in the biaxial TEVs. The current work shows that biaxial stretching is a novel and promising means to improve TEV generation. Furthermore, this novel system allows us to optimize biomechanical conditioning by unraveling the interrelationships among the

  13. Design and Use of a Novel Bioreactor for Regeneration of Biaxially Stretched Tissue-Engineered Vessels

    PubMed Central

    Huang, Angela Hai; Lee, Yong-Ung; Calle, Elizabeth A.; Boyle, Michael; Starcher, Barry C.; Humphrey, Jay D.

    2015-01-01

    Conventional bioreactors are used to enhance extracellular matrix (ECM) production and mechanical strength of tissue-engineered vessels (TEVs) by applying circumferential strain, which is uniaxial stretching. However, the resulting TEVs still suffer from inadequate mechanical properties, where rupture strengths and compliance values are still very different from native arteries. The biomechanical milieu of native arteries consists of both circumferential and axial loading. Therefore, to better simulate the physiological stresses acting on native arteries, we built a novel bioreactor system to enable biaxial stretching of engineered arteries during culture. This new bioreactor system allows for independent control of circumferential and axial stretching parameters, such as displacement and beat rate. The assembly and setup processes for this biaxial bioreactor system are reliable with a success rate greater than 75% for completion of long-term sterile culture. This bioreactor also supports side-by-side assessments of TEVs that are cultured under three types of mechanical conditions (static, uniaxial, and biaxial), all within the same biochemical environment. Using this bioreactor, we examined the impact of biaxial stretching on arterial wall remodeling of TEVs. Biaxial TEVs developed the greatest wall thickness compared with static and uniaxial TEVs. Unlike uniaxial loading, biaxial loading led to undulated collagen fibers that are commonly found in native arteries. More importantly, the biaxial TEVs developed the most mature elastin in the ECM, both qualitatively and quantitatively. The presence of mature extracellular elastin along with the undulated collagen fibers may contribute to the observed vascular compliance in the biaxial TEVs. The current work shows that biaxial stretching is a novel and promising means to improve TEV generation. Furthermore, this novel system allows us to optimize biomechanical conditioning by unraveling the interrelationships among the

  14. Design concepts for bioreactors in space

    NASA Technical Reports Server (NTRS)

    Seshan, P. K.; Peterson, G. R.; Beard, B.; Dunlop, E. H.

    1986-01-01

    Microbial food sources are becoming viable and more efficient alternatives to conventional food sources especially in the context of Closed Ecological Life Support Systems (CELSS) in space habitats. Since bioreactor designs for terrestrial operation will not readily apply to conditions of microgravity, there is an urgent need to learn about the differences. These differences cannot be easily estimated due to the complex nature of the mass transport and mixing mechanisms in fermenters. Therefore, a systematic and expeditious experimental program must be undertaken to obtain the engineering data necessary to lay down the foundations of designing bioreactors for microgravity. Two bioreactor design concepts presented represent two dissimilar approaches to grappling with the absence of gravity in space habitats and deserve to be tested for adoption as important components of the life support function aboard spacecrafts, space stations and other extra-terrestrial habitats.

  15. Numerical study of a high-speed miniature centrifugal compressor

    NASA Astrophysics Data System (ADS)

    Li, Xiaoyi

    A miniature centrifugal compressor is a key component of reverse Brayton cycle cryogenic cooling system. The system is commonly used to generate a low cryogenic temperature environment for electronics to increase their efficiency, or generate, store and transport cryogenic liquids, such as liquid hydrogen and oxygen, where space limit is also an issue. Because of space limitation, the compressor is composed of a radial IGV, a radial impeller and an axial-direction diffuser (which reduces the radial size because of smaller diameter). As a result of reduction in size, rotating speed of the impeller is as high as 313,000 rpm, and Helium is used as the working fluid, in order to obtain the required static pressure ratio/rise. Two main characteristics of the compressor---miniature and high-speed, make it distinct from conventional compressors. Higher compressor efficiency is required to obtain a higher COP (coefficient of performance) system. Even though miniature centrifugal compressors start to draw researchers' attention in recent years, understanding of the performance and loss mechanism is still lacking. Since current experimental techniques are not advanced enough to capture details of flow at miniature scale, numerical methods dominate miniature turbomachinery study. This work numerically studied a high speed miniature centrifugal compressor with commercial CFD code. The overall performance of the compressor was predicted with consideration of interaction between blade rows by using sliding mesh model. The law of similarity of turbomachinery was validated for small scale machines. It was found that the specific ratio effect needs to be considered when similarity law is applied. But Reynolds number effect can be neglected. The loss mechanism of each component was analyzed. Loss due to turning bend was significant in each component. Tip leakage loss of small scale turbomachines has more impact on the impeller performance than that of large scale ones. Because the

  16. Advances in miniature spectrometer and sensor development

    NASA Astrophysics Data System (ADS)

    Malinen, Jouko; Rissanen, Anna; Saari, Heikki; Karioja, Pentti; Karppinen, Mikko; Aalto, Timo; Tukkiniemi, Kari

    2014-05-01

    Miniaturization and cost reduction of spectrometer and sensor technologies has great potential to open up new applications areas and business opportunities for analytical technology in hand held, mobile and on-line applications. Advances in microfabrication have resulted in high-performance MEMS and MOEMS devices for spectrometer applications. Many other enabling technologies are useful for miniature analytical solutions, such as silicon photonics, nanoimprint lithography (NIL), system-on-chip, system-on-package techniques for integration of electronics and photonics, 3D printing, powerful embedded computing platforms, networked solutions as well as advances in chemometrics modeling. This paper will summarize recent work on spectrometer and sensor miniaturization at VTT Technical Research Centre of Finland. Fabry-Perot interferometer (FPI) tunable filter technology has been developed in two technical versions: Piezoactuated FPIs have been applied in miniature hyperspectral imaging needs in light weight UAV and nanosatellite applications, chemical imaging as well as medical applications. Microfabricated MOEMS FPIs have been developed as cost-effective sensor platforms for visible, NIR and IR applications. Further examples of sensor miniaturization will be discussed, including system-on-package sensor head for mid-IR gas analyzer, roll-to-roll printed Surface Enhanced Raman Scattering (SERS) technology as well as UV imprinted waveguide sensor for formaldehyde detection.

  17. Liquid storage of miniature boar semen.

    PubMed

    Shimatsu, Yoshiki; Uchida, Masaki; Niki, Rikio; Imai, Hiroshi

    2002-04-01

    The effects of liquid storage at 15 degrees C on the fertilizing ability of miniature pig semen were investigated. Characterization of ejaculated semen from 3 miniature boars was carried out. Semen volume and pH were similar among these boars. In one of the boars, sperm motility was slightly low, and sperm concentration and total number of sperm were significantly lower than in the others (P < 0.01). Seminal plasma of the semen was substituted with various extenders (Kiev, Androhep, BTS and Modena) by centrifugation and semen was stored for 7 days at 15 degrees C. Sperm motility was estimated daily at 37 degrees C. For complete substitution of seminal plasma, Modena was significantly more efficient than the other extenders (P < 0.001) in retaining sperm motility. Semen from each of the 3 miniature boars that had been stored for 5 to 7 days at 15 degrees C in Modena was used for artificial insemination of 15 miniature sows. The farrowing rates were 100, 100 and 60%, and litter sizes were 6.4 +/- 1.5, 5.8 +/- 0.8 and 5.0 +/- 1.0 for each boar semen, respectively. The boar that sired the smallest farrowing rate was the same one that showed lower seminal quality with respect to sperm motility, sperm concentration and total number of sperm. These results suggest that miniature boar semen can be stored for at least 5 days at 15 degrees C by the substitution of seminal plasma with Modena extender.

  18. Bioreactor and methods for producing synchronous cells

    NASA Technical Reports Server (NTRS)

    Helmstetter, Charles E. (Inventor); Thornton, Maureen (Inventor); Gonda, Steve (Inventor)

    2005-01-01

    Apparatus and methods are directed to a perfusion culture system in which a rotating bioreactor is used to grow cells in a liquid culture medium, while these cells are attached to an adhesive-treated porous surface. As a result of this arrangement and its rotation, the attached cells divide, with one cell remaining attached to the substrate, while the other cell, a newborn cell is released. These newborn cells are of approximately the same age, that are collected upon leaving the bioreactor. The populations of newborn cells collected are of synchronous and are minimally, if at all, disturbed metabolically.

  19. Transport and kinetics in sandwiched membrane bioreactors.

    PubMed

    Jeong, Y S; Vieth, W R; Matsuura, T

    1991-01-01

    A bioreactor in which living yeast cells are sandwiched between an ultrafiltration membrane and a reverse osmosis membrane was constructed, and experiments were performed for the conversion of substrate glucose to product ethanol. A set of equations that include both transport through a series of barrier layers and bioreaction rate were developed to predict the performance of the sandwich bioreactor. The above equations were solved by using numerical values for the transport parameter and the bioreaction rate constant, and the results are compared with the experimental data.

  20. The oceanic crust as a bioreactor

    NASA Astrophysics Data System (ADS)

    Staudigel, Hubert; Tebo, Bradley; Yayanos, Art; Furnes, Harald; Kelley, Katie; Plank, Terry; Muehlenbachs, Karlis

    Various lines of evidence suggest that large portions of hydrothermal systems in the oceanic crust acts like a giant bioreactor that mediates water-rock exchange and buffers the chemical composition of seawater. We review the current literature and present new chemical, biological and petrographic data on microbially mediated alteration of glass in the oceanic crust. Microbial alteration of glass displays characteristic bioalteration features, in particular in the alteration fronts around residual glass in the oceanic crust, suggesting that microbes take on an active role in its dissolution. Such features are found throughout the oceanic crust ranging in age from a few million to 170 Ma and they are found down to crustal depths of 500 m, possibly defining a Deep Oceanic Biosphere (DOB) that covers up to 2/3 of the earth's surface area. Microbial glass alteration substantially increases the active surface area of dissolving glass particles thereby enhancing the reaction rates during microbially aided dissolution. Microbially mediated glass alteration involves the establishment of two types of diffusion barriers including hydration rinds and biofilms that play an important role in mediating glass alteration. In particular biofilms may be very active by creating a localized chemical environment conducive to glass alteration, and by sequestering dissolved chemical inventory from solution. When compared with abiotic alteration of the oceanic crust, bio-alteration causes more rapid deposition of biotic and abiotic reaction products in the oceanic crust that result in a more effective removal of elements from seawater and a more rapid sealing of the oceanic crust. Thus, it is likely that microbial activity increases the fluxes of seawater components into the crust, while reducing the low—temperature flux of basalt components into seawater. However, much about the microbial activity and its relationships to the chemistry of hydrothermal systems still remains to be

  1. Differentiation of cartilaginous anlagen in entire embryonic mouse limbs cultured in a rotating bioreactor

    NASA Astrophysics Data System (ADS)

    Montufar-Solis, D.; Oakley, C. R.; Jefferson, Y.; Duke, P. J.

    2003-10-01

    Mechanisms involved in development of the embryonic limb have remained the same throughout eons of genetic and environmental evolution under Earth gravity (lg). During the spaceflight era it has been of interest to explore the ancient theory that form of the skeleton develops in response to gravity, and that changes in gravitational forces can change the developmental pattern of the limb. This has been shown in vivo and in vitro, allowing the hypergravity of centrifugation and microgravity of space to be used as tools to increase our knowledge of limb development. In recapitulations of spaceflight experiments, premetatarsals were cultured in suspension in a bioreactor, and found to be shorter and less differentiated than those cultured in standard culture dishes. This study only measured length of the metatarsals, and did not account for possible changes due to the skeletal elements having a more in vivo 3D shape while in suspension vs. flattened tissues compressed by their own weight. A culture system with an outcome closer to in vivo and that supports growth of younger limb buds than traditional systems will allow studies of early Hox gene expression, and contribute to the understanding of very early stages of development. The purpose of the current experiment was to determine if entire limb buds could be cultured in the bioreactor, and to compare the growth and differentiation with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were cultured for six days, either in the bioreactor or in center-well organ culture dishes, fixed, and embedded for histology. E13 specimens grown in culture dishes were flat, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections showed excellent cartilage differentiation in both culture systems, with more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Younger limb buds fused together during culture, so an additional set of El 1

  2. Differentiation of cartilaginous anlage in entire embryonic mouse limbs cultured in a rotating bioreactor.

    NASA Astrophysics Data System (ADS)

    Duke, P.; Oakley, C.; Montufar-Solis, D.

    The embryonic mammalian limb is sensitive both in vivo and in vitro to changes in gravitational force. Hypergravity of centrifugation and microgravity of space decreased size of elements due to precocious or delayed chondrogenesis respectively. In recapitulating spaceflight experiments, premetatarsals were cultured in suspension in a low stress, low sheer rotating bioreactor, and found to be shorter than those cultured in standard culture dishes, and cartilage development was delayed. This study only measured length of the metatarsals, and did not account for possible changes in width and/or in form of the skeletal elements. Shorter cartilage elements in limbbuds cultured in the bioreactor may be due to the ability of the system to reproduce a more in vivo 3D shape than traditional organ cultures. Tissues subjected to traditional organ cultures become flattened by their own weight, attachment to the filter, and restrictions imposed by nutrient diffusion. The purpose of the current experiment was to determine if entire limb buds could be successfully cultured in the bioreactor, and to compare the effects on 3D shape with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were placed either in the bioreactor, in Trowell culture, or fixed as controls. Limbbuds were cultured for six days, fixed, and processed either as whole mounts or embedded for histology. Qualitative analysis revealed that the Trowell culture specimens were flattened, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections of limbbuds from both types of cultures had excellent cartilage differentiation, with apparently more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Morphometric quantitation of the cartilaginous elements for comparisons of the two culture systems was complicated due to some limb buds fusing together during culture. This problem was especially noticeable in the younger limbs, and

  3. Method and system for assembling miniaturized devices

    DOEpatents

    Montesanti, Richard C.; Klingmann, Jeffrey L.; Seugling, Richard M.

    2013-03-12

    An apparatus for assembling a miniaturized device includes a manipulator system including six manipulators operable to position and orient components of the miniaturized device with submicron precision and micron-level accuracy. The manipulator system includes a first plurality of motorized axes, a second plurality of manual axes, and force and torque and sensors. Each of the six manipulators includes at least one translation stage, at least one rotation stage, tooling attached to the at least one translation stage or the at least one rotation stage, and an attachment mechanism disposed at a distal end of the tooling and operable to attach at least a portion of the miniaturized device to the tooling. The apparatus also includes an optical coordinate-measuring machine (OCMM) including a machine-vision system, a laser-based distance-measuring probe, and a touch probe. The apparatus also includes an operator control system coupled to the manipulator system and the OCMM.

  4. FY 2005 Miniature Spherical Retroreflectors Final Report

    SciTech Connect

    Anheier, Norman C.; Bernacki, Bruce E.; Johnson, Bradley R.; Riley, Brian J.; Sliger, William A.

    2005-12-01

    Research done by the Infrared Photonics team at Pacific Northwest National Laboratory (PNNL) is focused on developing miniature spherical retroreflectors using the unique optical and material properties of chalcogenide glass to reduce both performance limiting spherical and chromatic aberrations. The optimized optical performance will provide efficient signal retroreflection that enables a broad range of remote detection scenarios for mid-wave infrared (MWIR) and long-wave infrared (LWIR) sensing applications. Miniature spherical retroreflectors can be developed to aid in the detection of signatures of nuclear proliferation or other chemical vapor or radiation signatures. Miniature spherical retroreflectors are not only well suited to traditional bistatic LIDAR methods for chemical plume detection and identification, but could enable remote detection of difficult semi-volatile chemical materials or low level radiation sources.

  5. FY 2006 Miniature Spherical Retroreflectors Final Report

    SciTech Connect

    Anheier, Norman C.; Bernacki, Bruce E.; Krishnaswami, Kannan

    2006-12-28

    Research done by the Infrared Photonics team at Pacific Northwest National Laboratory (PNNL) is focused on developing miniature spherical retroreflectors using the unique optical and material properties of chalcogenide glass to reduce both performance limiting spherical aberrations. The optimized optical performance will provide efficient signal retroreflection that enables a broad range of remote detection scenarios for mid-wave infrared (MWIR) and long-wave infrared (LWIR) sensing applications. Miniature spherical retroreflectors can be developed to aid in the detection of signatures of nuclear proliferation or other chemical vapor or radiation signatures. Miniature spherical retroreflectors are not only well suited to traditional LIDAR methods for chemical plume detection and identification, but could enable remote detection of difficult semi-volatile chemical materials or low level radiation sources.

  6. Acral mutilation syndrome in a miniature pinscher.

    PubMed

    Bardagí, M; Montoliu, P; Ferrer, L; Fondevila, D; Pumarola, M

    2011-01-01

    Acral mutilation syndrome (AMS) is a rare canine hereditary sensory neuropathy that results in progressive mutilation of the distal extremities and which has been reported only in German short-haired pointers, English pointers, English springer spaniels and French spaniels. The present report describes a case of AMS in an 18-month-old female miniature pinscher with progressive self-mutilation of the hind feet. The dog did not respond to any treatment and was humanely destroyed at the age of 30 months. Microscopical findings post mortem were restricted to the nervous system and were compatible with AMS. This is the first case of AMS described in a miniature pinscher. It is not known if the disease was the result of a point mutation in this particular dog or if the miniature pinscher breed will evolve to become a breed predisposed to AMS.

  7. Compact Miniaturized Antenna for 210 MHz RFID

    NASA Technical Reports Server (NTRS)

    Lee, Richard Q.; Chun, Kue

    2008-01-01

    This paper describes the design and simulation of a miniaturized square-ring antenna. The miniaturized antenna, with overall dimensions of approximately one tenth of a wavelength (0.1 ), was designed to operate at around 210 MHz, and was intended for radio-frequency identification (RFID) application. One unique feature of the design is the use of a parasitic element to improve the performance and impedance matching of the antenna. The use of parasitic elements to enhance the gain and bandwidth of patch antennas has been demonstrated and reported in the literature, but such use has never been applied to miniaturized antennas. In this work, we will present simulation results and discuss design parameters and their impact on the antenna performance.

  8. Miniature plastic gripper and fabrication method

    DOEpatents

    Benett, William J.; Krulevitch, Peter A.; Lee, Abraham P.; Northrup, Milton A.; Folta, James A.

    1997-01-01

    A miniature plastic gripper actuated by inflation of a miniature balloon and method of fabricating same. The gripper is constructed of either heat-shrinkable or heat-expandable plastic tubing and is formed around a mandrel, then cut to form gripper prongs or jaws and the mandrel removed. The gripper is connected at one end with a catheter or tube having an actuating balloon at its tip, whereby the gripper is opened or closed by inflation or deflation of the balloon. The gripper is designed to removably retain a member to which is connected a quantity or medicine, plugs, or micro-components. The miniature plastic gripper is inexpensive to fabricate and can be used for various applications, such as gripping, sorting, or placing of micron-scale particles for analysis.

  9. Fabrication method for miniature plastic gripper

    DOEpatents

    Benett, William J.; Krulevitch, Peter A.; Lee, Abraham P.; Northrup, Milton A.; Folta, James A.

    1998-01-01

    A miniature plastic gripper actuated by inflation of a miniature balloon and method of fabricating same. The gripper is constructed of either heat-shrinkable or heat-expandable plastic tubing and is formed around a mandrel, then cut to form gripper prongs or jaws and the mandrel removed. The gripper is connected at one end with a catheter or tube having an actuating balloon at its tip, whereby the gripper is opened or dosed by inflation or deflation of the balloon. The gripper is designed to removably retain a member to which is connected a quantity or medicine, plugs, or micro-components. The miniature plastic gripper is inexpensive to fabricate and can be used for various applications, such as gripping, sorting, or placing of micron-scale particles for analysis.

  10. A miniature robotic plane meteorological sounding system

    NASA Astrophysics Data System (ADS)

    Ma, Shuqing; Chen, Hongbin; Wang, Gai; Pan, Yi; Li, Qiang

    2004-12-01

    This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and flight control system, and a ground-based system. Take-off and landing of the miniature aircraft are guided by radio control, and the flight of the robotic plane along a pre-designed trajectory is automatically piloted by an onboard navigation system. The observed meteorological data as well as all flight information are sent back in real time to the ground, then displayed and recorded by the ground-based computer. The ground-based subsystem can also transmit instructions to the air-borne control subsystem. Good system performance has been demonstrated by more than 300 hours of flight for atmospheric sounding.

  11. Miniature plastic gripper and fabrication method

    DOEpatents

    Benett, W.J.; Krulevitch, P.A.; Lee, A.P.; Northrup, M.A.; Folta, J.A.

    1997-03-11

    A miniature plastic gripper actuated by inflation of a miniature balloon and method of fabricating same are disclosed. The gripper is constructed of either heat-shrinkable or heat-expandable plastic tubing and is formed around a mandrel, then cut to form gripper prongs or jaws and the mandrel removed. The gripper is connected at one end with a catheter or tube having an actuating balloon at its tip, whereby the gripper is opened or closed by inflation or deflation of the balloon. The gripper is designed to removably retain a member to which is connected a quantity or medicine, plugs, or micro-components. The miniature plastic gripper is inexpensive to fabricate and can be used for various applications, such as gripping, sorting, or placing of micron-scale particles for analysis. 8 figs.

  12. Fabrication method for miniature plastic gripper

    DOEpatents

    Benett, W.J.; Krulevitch, P.A.; Lee, A.P.; Northrup, M.A.; Folta, J.A.

    1998-07-21

    A miniature plastic gripper is described actuated by inflation of a miniature balloon and method of fabricating same. The gripper is constructed of either heat-shrinkable or heat-expandable plastic tubing and is formed around a mandrel, then cut to form gripper prongs or jaws and the mandrel removed. The gripper is connected at one end with a catheter or tube having an actuating balloon at its tip, whereby the gripper is opened or dosed by inflation or deflation of the balloon. The gripper is designed to removably retain a member to which is connected a quantity or medicine, plugs, or micro-components. The miniature plastic gripper is inexpensive to fabricate and can be used for various applications, such as gripping, sorting, or placing of micron-scale particles for analysis. 8 figs.

  13. Miniature Long-life Space Cryocoolers

    NASA Technical Reports Server (NTRS)

    Tward, E.

    1993-01-01

    TRW has designed, built, and tested a miniature integral Stirling cooler and a miniature pulse tube cooler intended for long-life space application. Both efficient, low-vibration coolers were developed for cooling IR sensors to temperatures as low as 50 K on lightsats. The vibrationally balanced nonwearing design Stirling cooler incorporates clearance seals maintained by flexure springs for both the compressor and the drive displacer. The design achieved its performance goal of 0.25 W at 65 K for an input power to the compressor of 12 W. The cooler recently passed launch vibration tests prior to its entry into an extended life test and its first scheduled flight in 1995. The vibrationally balanced, miniature pulse tube cooler intended for a 10-year long-life space application incorporates a flexure bearing compressor vibrationally balanced by a motor-controlled balancer and a completely passive pulse tube cold head.

  14. A multicommutated tester of bioreactors for flow analysis.

    PubMed

    Pokrzywnicka, Marta; Kamiński, Jacek; Michalec, Michał; Koncki, Robert; Tymecki, Łukasz

    2016-11-01

    Enzymes are often used in the modern analytical procedures allowing selective recognition and conversion of target analytes into easily detected products. In flow analysis systems, enzymes are predominantly applied in the immobilized forms as flow-through bioreactors. In this research the multicommutated flow analysis (MCFA) system for evaluation and comparison of analytical parameters of bioreactors has been developed. The MCFA manifold allows simultaneous testing up to four bioreactors, but if necessary their number can be easily increased. The system allows comparison of several parameters of tested bioreactors including activity, repeatability, reproducibility, operational and storage stability. The performance of developed bioreactor tester is presented using urea-urease model system based on plastic open-tubular bioreactor with covalently immobilized enzyme. Product of enzymatic reaction is detected using two different chemical methods and by dedicated optoelectronic ammonium detectors. Moreover, the utility of developed MCFA manifold for evaluation of other enzyme bioreactors is demonstrated. PMID:27591609

  15. Design of a miniature explosive isentropic compression experiment

    SciTech Connect

    Tasker, Douglas G

    2010-01-01

    The purpose of this design study is to adapt the High Explosive Pulsed Power Isentropic Compression Experiment (HEPP-ICE) to milligram quantities of materials at stresses of {approx}100 GPa. For this miniature application we assume that a parallel plate stripline of {approx}2.5 mm width is needed to compress the samples. In any parallel plate load, the rising currents flow preferentially along the outside edges of the load where the specific impedance is a minimum [1]. Therefore, the peak current must be between 1 and 2 MA to reach a stress of 100 GPa in the center of a 2.5 mm wide parallel plate load; these are small relative to typical HEPP-ICE currents. We show that a capacitor bank alone exceeds the requirements of this miniature ICE experiment and a flux compression generator (FCG) is not necessary. The proposed circuit will comprise one half of the 2.4-MJ bank, i.e., the 6-mF, 20-kV, 1.2 MJ capacitor bank used in the original HEPP-ICE circuit. Explosive opening and closing switches will still be required because the rise time of the capacitor circuit would be of the order of 30 {micro}s without them. For isentropic loading in these small samples, stress rise times of {approx}200 ns are required.

  16. FY 2007 Miniature Spherical Retroreflectors Final Report

    SciTech Connect

    Anheier, Norman C.; Bernacki, Bruce E.; Krishnaswami, Kannan

    2008-02-20

    Miniature spherical retroreflectors, less than 8 millimeters in diameter, are currently being developed to enhance remote optical detection of nuclear proliferation activities. These retroreflecting spheres resemble small, sand-colored marbles that have the unique optical property of providing a strong reflection directly back to the source (i.e., retroreflecting) when illuminated with a laser. The addition of specific coatings, sensitive to specific chemicals or radioactive decay in the environment, can be applied to the surface of these retroreflectors to provide remote detection of nuclear proliferation activities. The presence of radioactive decay (e.g., alpha, gamma, neutron) or specific chemicals in the environment (e.g., TBP, acids) will change the optical properties of the spheres in a predictable fashion, thus indicating the presence or absence of the target materials. One possible scenario might employ an airborne infrared laser system (e.g., quantum-cascade lasers) to illuminate a section of ground littered with these retroreflective spheres. Depending on the coating and the presence of a specific chemical or radioisotope in the environment, the return signal would be modified in some predictable fashion because of fluorescence, frequency shifting, intensity attenuation/enhancement, or change in polarization. Research conducted in FY 2007 focused on developing novel optical fabrication processes and exploiting the unique material properties of chalcogenide infrared-transparent glass (germanium-arsenic-sulfur-tellurium compounds) to produce highly efficient retroreflectors. Pacific Northwest National Laboratory’s approach provides comparable performance to the ideal graded index sphere concept, developed by R. K. Luneburg in 1944 (Luneburg 1944), while greatly reducing the complexity in fabrication by utilizing chalcogenide glass materials and compression-molding processes.

  17. A Miniaturized Transcutaneous System for Continuous Glucose Monitoring

    PubMed Central

    Croce, Robert A.; Vaddiraju, SanthiSagar; Kondo, Jun; Wang, Yan; Zuo, Liang; Zhu, Kai; Islam, Syed K.; Burgess, Diane; Papadimitrakopoulos, Fotios; Jain, Faquir C.

    2012-01-01

    Implantable sensors for continuous glucose monitoring hold great potential for optimal diabetes management. This is often undermined by a variety of issues associated with: (1) negative tissue response; (2) poor sensor performance; and (3) lack of device miniaturization needed to reduce implantation trauma. Herein, we report our initial results towards constructing an implantable device that simultaneously address all three aforementioned issues. In terms of device miniaturization, a highly miniaturized CMOS (complementary metal-oxide-semiconductor) potentiostat and signal processing unit was employed (with a combined area of 0.665 mm2). The signal processing unit converts the current generated by a transcutaneous, Clark-type amperometric sensor to output frequency in a linear fashion. The Clark-type amperometric sensor employs stratification of five functional layers to attain a well-balanced mass transfer which in turn yields a linear sensor response from 0 to 25 mM of glucose concentration, well beyond the physiologically observed (2 to 22 mM) range. In addition, it is coated with a thick polyvinyl alcohol (PVA) hydrogel with embedded poly(lactic-co-glycolic acid) (PLGA) microspheres intended to provide continuous, localized delivery of dexamethasone to suppress inflammation and fibrosis. In vivo evaluation in rat model has shown that the transcutaneous sensor system reproducibly tracks repeated glycemic events. Clarke’s error grid analysis on the as –obtained glycemic data has indicated that all of the measured glucose readings fell in the desired Zones A & B and none fell in the erroneous Zones C, D and E. Such reproducible operation of the transcutaneous sensor system, together with low power (140 μW) consumption and capability for current-to-frequency conversion renders this a versatile platform for continuous glucose monitoring and other biomedical sensing devices. PMID:22992979

  18. Temperature and Substrate Control Woodchip Bioreactor Performance in Reducing Tile Nitrate Loads in East-Central Illinois.

    PubMed

    David, Mark B; Gentry, Lowell E; Cooke, Richard A; Herbstritt, Stephanie M

    2016-05-01

    Tile drainage is the major source of nitrate in the upper Midwest, and end-of-tile removal techniques such as wood chip bioreactors have been installed that allow current farming practices to continue, with nitrate removed through denitrification. There have been few multiyear studies of bioreactors examining controls on nitrate removal rates. We evaluated the nitrate removal performance of two wood chip bioreactors during the first 3 yr of operation and examined the major factors that regulated nitrate removal. Bioreactor 2 was subject to river flooding, and performance was not assessed. Bioreactor 1 had average monthly nitrate removal rates of 23 to 44 g N m d in Year 1, which decreased to 1.2 to 11 g N m d in Years 2 and 3. The greater N removal rates in Year 1 and early in Year 2 were likely due to highly degradable C in the woodchips. Only late in Year 2 and in Year 3 was there a strong temperature response in the nitrate removal rate. Less than 1% of the nitrate removed was emitted as NO. Due to large tile inputs of nitrate (729-2127 kg N) at high concentrations (∼30 mg nitrate N L) in Years 2 and 3, overall removal efficiency was low (3 and 7% in Years 2 and 3, respectively). Based on a process-based bioreactor performance model, Bioreactor 1 would have needed to be 9 times as large as the current system to remove 50% of the nitrate load from this 20-ha field. PMID:27136147

  19. Research on miniature gas analysis systems

    NASA Technical Reports Server (NTRS)

    Angell, J. B.

    1974-01-01

    Technology for fabricating very small valves, whose function will be to introduce a small sample of the gas to be analyzed into the main carrier gas stream flowing through the chromatograph column is described. In addition, some analyses were made of the factors governing the resolution of gas chromatographs, particularly those with miniature columns. These analyses show how important the column lining thickness is in governing the ability of a miniature column to separate components of an unknown gas. A brief description of column lining factors is included. Preliminary work on a super small thermistor detector is included.

  20. Miniature rotating transmissive optical drum scanner

    NASA Technical Reports Server (NTRS)

    Lewis, Robert (Inventor); Parrington, Lawrence (Inventor); Rutberg, Michael (Inventor)

    2013-01-01

    A miniature rotating transmissive optical scanner system employs a drum of small size having an interior defined by a circumferential wall rotatable on a drum axis, an optical element positioned within the interior of the drum, and a light-transmissive lens aperture provided at an angular position in the circumferential wall of the drum for scanning a light beam to or from the optical element in the drum along a beam azimuth angle as the drum is rotated. The miniature optical drum scanner configuration obtains a wide scanning field-of-view (FOV) and large effective aperture is achieved within a physically small size.

  1. Coulomb Repulsion in Miniature Ion Mobility Spectrometry

    SciTech Connect

    Xu, J.; Whitten, W.B.; Ramsey, J.M.

    1999-08-08

    We have undertaken a study of ion mobility resolution in a miniature ion mobility spectrometer with a drift channel 1.7 mm in diameter and 35 mm in length. The device attained a maximum resolution of 14 in separating ions of NO, O{sub 2}, and methyl iodine. The ions were generated by pulses from a frequency-quadrupled Nd:YAG laser. Broadening due to Coulomb repulsion was modeled theoretically and shown experimentally to have a major effect on the resolution of the miniature device.

  2. Miniature biotelemeter gives multichannel wideband biomedical data

    NASA Technical Reports Server (NTRS)

    Carraway, J. B.

    1972-01-01

    A miniature biotelemeter was developed for sensing and transmitting multiple channels of biomedical data over a radio link. The design of this miniature, 10-channel, wideband (5 kHz/channel), pulse amplitude modulation/ frequency modulation biotelemeter takes advantage of modern device technology (e.g., integrated circuit operational amplifiers, complementary symmetry/metal oxide semiconductor logic, and solid state switches) and hybrid packaging techniques. The telemeter is being used to monitor 10 channels of neuron firings from specific regions of the brain in rats implanted with chronic electrodes. Design, fabrication, and testing of an engineering model biotelemeter are described.

  3. Batch fabrication of precision miniature permanent magnets

    DOEpatents

    Christenson, Todd R.; Garino, Terry J.; Venturini, Eugene L.

    2002-01-01

    A new class of processes for fabrication of precision miniature rare earth permanent magnets is disclosed. Such magnets typically have sizes in the range 0.1 to 10 millimeters, and dimensional tolerances as small as one micron. Very large magnetic fields can be produced by such magnets, lending to their potential application in MEMS and related electromechanical applications, and in miniature millimeter-wave vacuum tubes. This abstract contains simplifications, and is supplied only for purposes of searching, not to limit or alter the scope or meaning of any claims herein.

  4. Continuous flow nitration in miniaturized devices

    PubMed Central

    2014-01-01

    Summary This review highlights the state of the art in the field of continuous flow nitration with miniaturized devices. Although nitration has been one of the oldest and most important unit reactions, the advent of miniaturized devices has paved the way for new opportunities to reconsider the conventional approach for exothermic and selectivity sensitive nitration reactions. Four different approaches to flow nitration with microreactors are presented herein and discussed in view of their advantages, limitations and applicability of the information towards scale-up. Selected recent patents that disclose scale-up methodologies for continuous flow nitration are also briefly reviewed. PMID:24605161

  5. Design of a biaxial mechanical loading bioreactor for tissue engineering.

    PubMed

    Bilgen, Bahar; Chu, Danielle; Stefani, Robert; Aaron, Roy K

    2013-01-01

    We designed a loading device that is capable of applying uniaxial or biaxial mechanical strain to a tissue engineered biocomposites fabricated for transplantation. While the device primarily functions as a bioreactor that mimics the native mechanical strains, it is also outfitted with a load cell for providing force feedback or mechanical testing of the constructs. The device subjects engineered cartilage constructs to biaxial mechanical loading with great precision of loading dose (amplitude and frequency) and is compact enough to fit inside a standard tissue culture incubator. It loads samples directly in a tissue culture plate, and multiple plate sizes are compatible with the system. The device has been designed using components manufactured for precision-guided laser applications. Bi-axial loading is accomplished by two orthogonal stages. The stages have a 50 mm travel range and are driven independently by stepper motor actuators, controlled by a closed-loop stepper motor driver that features micro-stepping capabilities, enabling step sizes of less than 50 nm. A polysulfone loading platen is coupled to the bi-axial moving platform. Movements of the stages are controlled by Thor-labs Advanced Positioning Technology (APT) software. The stepper motor driver is used with the software to adjust load parameters of frequency and amplitude of both shear and compression independently and simultaneously. Positional feedback is provided by linear optical encoders that have a bidirectional repeatability of 0.1 μm and a resolution of 20 nm, translating to a positional accuracy of less than 3 μm over the full 50 mm of travel. These encoders provide the necessary position feedback to the drive electronics to ensure true nanopositioning capabilities. In order to provide the force feedback to detect contact and evaluate loading responses, a precision miniature load cell is positioned between the loading platen and the moving platform. The load cell has high accuracies of 0

  6. Design of a biaxial mechanical loading bioreactor for tissue engineering.

    PubMed

    Bilgen, Bahar; Chu, Danielle; Stefani, Robert; Aaron, Roy K

    2013-04-25

    We designed a loading device that is capable of applying uniaxial or biaxial mechanical strain to a tissue engineered biocomposites fabricated for transplantation. While the device primarily functions as a bioreactor that mimics the native mechanical strains, it is also outfitted with a load cell for providing force feedback or mechanical testing of the constructs. The device subjects engineered cartilage constructs to biaxial mechanical loading with great precision of loading dose (amplitude and frequency) and is compact enough to fit inside a standard tissue culture incubator. It loads samples directly in a tissue culture plate, and multiple plate sizes are compatible with the system. The device has been designed using components manufactured for precision-guided laser applications. Bi-axial loading is accomplished by two orthogonal stages. The stages have a 50 mm travel range and are driven independently by stepper motor actuators, controlled by a closed-loop stepper motor driver that features micro-stepping capabilities, enabling step sizes of less than 50 nm. A polysulfone loading platen is coupled to the bi-axial moving platform. Movements of the stages are controlled by Thor-labs Advanced Positioning Technology (APT) software. The stepper motor driver is used with the software to adjust load parameters of frequency and amplitude of both shear and compression independently and simultaneously. Positional feedback is provided by linear optical encoders that have a bidirectional repeatability of 0.1 μm and a resolution of 20 nm, translating to a positional accuracy of less than 3 μm over the full 50 mm of travel. These encoders provide the necessary position feedback to the drive electronics to ensure true nanopositioning capabilities. In order to provide the force feedback to detect contact and evaluate loading responses, a precision miniature load cell is positioned between the loading platen and the moving platform. The load cell has high accuracies of 0

  7. An experimental study on Sokkuram Cave Temple dome's indoor environment using a miniature model in winter season

    SciTech Connect

    Kong, S.H.; Chung, K.S.; Park, J.S.; Shin, I.S.; Han, H.T.

    1999-07-01

    Currently, there are many researches on the analysis of indoor environment in Sokkuram Cave Temple. However, there is not enough researches about an experimental study on the dome's indoor environment in Sokkuram Cave Temple using a miniature model. The purpose of this investigation is to measure and analyze characteristics of indoor environment such as relative humidity, dry bulb temperature and air velocity in the miniature model of Sokkuram Cave dome during winter season.

  8. Establishing Liver Bioreactors for In Vitro Research.

    PubMed

    Rebelo, Sofia P; Costa, Rita; Sousa, Marcos F Q; Brito, Catarina; Alves, Paula M

    2015-01-01

    In vitro systems that can effectively model liver function for long periods of time are fundamental tools for preclinical research. Nevertheless, the adoption of in vitro research tools at the earliest stages of drug development has been hampered by the lack of culture systems that offer the robustness, scalability, and flexibility necessary to meet industry's demands. Bioreactor-based technologies, such as stirred tank bioreactors, constitute a feasible approach to aggregate hepatic cells and maintain long-term three-dimensional cultures. These three-dimensional cultures sustain the polarity, differentiated phenotype, and metabolic performance of human hepatocytes. Culture in computer-controlled stirred tank bioreactors allows the maintenance of physiological conditions, such as pH, dissolved oxygen, and temperature, with minimal fluctuations. Moreover, by operating in perfusion mode, gradients of soluble factors and metabolic by-products can be established, aiming at resembling the in vivo microenvironment. This chapter provides a protocol for the aggregation and culture of hepatocyte spheroids in stirred tank bioreactors by applying perfusion mode for the long-term culture of human hepatocytes. This in vitro culture system is compatible with feeding high-throughput screening platforms for the assessment of drug elimination pathways, being a useful tool for toxicology research and drug development in the preclinical phase.

  9. Engineering stem cell niches in bioreactors

    PubMed Central

    Liu, Meimei; Liu, Ning; Zang, Ru; Li, Yan; Yang, Shang-Tian

    2013-01-01

    Stem cells, including embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells and amniotic fluid stem cells have the potential to be expanded and differentiated into various cell types in the body. Efficient differentiation of stem cells with the desired tissue-specific function is critical for stem cell-based cell therapy, tissue engineering, drug discovery and disease modeling. Bioreactors provide a great platform to regulate the stem cell microenvironment, known as “niches”, to impact stem cell fate decision. The niche factors include the regulatory factors such as oxygen, extracellular matrix (synthetic and decellularized), paracrine/autocrine signaling and physical forces (i.e., mechanical force, electrical force and flow shear). The use of novel bioreactors with precise control and recapitulation of niche factors through modulating reactor operation parameters can enable efficient stem cell expansion and differentiation. Recently, the development of microfluidic devices and microbioreactors also provides powerful tools to manipulate the stem cell microenvironment by adjusting flow rate and cytokine gradients. In general, bioreactor engineering can be used to better modulate stem cell niches critical for stem cell expansion, differentiation and applications as novel cell-based biomedicines. This paper reviews important factors that can be more precisely controlled in bioreactors and their effects on stem cell engineering. PMID:24179601

  10. MONITORING APPROACHES FOR BIOREACTOR LANDFILLS - Report

    EPA Science Inventory

    Experimental bioreactor landfill operations at operating Municipal Solid Waste (MSW) landfills can be approved under the research development and demonstration (RD&D) provisions of 30CFR 258.4. To provide a basis for consistent data collection for future decision-making in suppor...

  11. LANDFILL BIOREACTOR PERFORMANCE, SECOND INTERIM REPORT

    EPA Science Inventory

    A bioreactor landfill is a landfill that is operated in a manner that is expected to increase the rate and extent of waste decomposition, gas generation, and settlement compared to a traditional landfill. This Second Interim Report was prepared to provide an interpretation of fie...

  12. Continuous-Flow Gas-Phase Bioreactors

    NASA Technical Reports Server (NTRS)

    Wise, Donald L.; Trantolo, Debra J.

    1994-01-01

    Continuous-flow gas-phase bioreactors proposed for biochemical, food-processing, and related industries. Reactor contains one or more selected enzymes dehydrated or otherwise immobilized on solid carrier. Selected reactant gases fed into reactor, wherein chemical reactions catalyzed by enzyme(s) yield product biochemicals. Concept based on discovery that enzymes not necessarily placed in traditional aqueous environments to function as biocatalysts.

  13. Human cell culture in a space bioreactor

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.

    1988-01-01

    Microgravity offers new ways of handling fluids, gases, and growing mammalian cells in efficient suspension cultures. In 1976 bioreactor engineers designed a system using a cylindrical reactor vessel in which the cells and medium are slowly mixed. The reaction chamber is interchangeable and can be used for several types of cell cultures. NASA has methodically developed unique suspension type cell and recovery apparatus culture systems for bioprocess technology experiments and production of biological products in microgravity. The first Space Bioreactor was designed for microprocessor control, no gaseous headspace, circulation and resupply of culture medium, and slow mixing in very low shear regimes. Various ground based bioreactors are being used to test reactor vessel design, on-line sensors, effects of shear, nutrient supply, and waste removal from continuous culture of human cells attached to microcarriers. The small Bioreactor is being constructed for flight experiments in the Shuttle Middeck to verify systems operation under microgravity conditions and to measure the efficiencies of mass transport, gas transfer, oxygen consumption and control of low shear stress on cells.

  14. Denitrifying bioreactor clogging potential during wastewater treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chemoheterotrophic denitrification technologies using woodchips as a solid carbon source (i.e., woodchip bioreactors) have been widely trialed for treatment of diffuse-source agricultural nitrogen pollution. There is growing interest in the use of this simple, relatively low-cost biological wastewat...

  15. Membrane bioreactors and their uses in wastewater treatments.

    PubMed

    Le-Clech, Pierre

    2010-12-01

    With the current need for more efficient and reliable processes for municipal and industrial wastewaters treatment, membrane bioreactor (MBR) technology has received considerable attention. After just a couple of decades of existence, MBR can now be considered as an established wastewater treatment system, competing directly with conventional processes like activated sludge treatment plant. However, MBR processes still suffer from major drawbacks, including high operational costs due to the use of anti-fouling strategies applied to the system to maintain sustainable filtration conditions. Moreover, this specific use of membranes has not reached full maturity yet, as MBR suppliers and users still lack experience regarding the long-term performances of the system. Still, major improvements of the MBR design and operation have been witnessed over the recent years, making MBR an option of choice for wastewater treatment and reuse. This mini-review reports recent developments and current research trends in the field.

  16. Bubble Experiments on the Hydrodynamic Focusing Bioreactor-Space (HFB-S)

    NASA Technical Reports Server (NTRS)

    Niederhaus, Charles; Nahra, Henry; Gonda, Steve; Lupo, Pamela; Kleis, Stanley; Geffert, Sandra; Kizito, John; Robinson, Stewart

    2002-01-01

    The Hydrodynamic Focusing Bioreactor-Space (HFB-S) is being developed as a drop-in replacement for the Rotating Wall Perfused Vessel (RWPV) bioreactor currently planned for use on the International Space Station (ISS). Only the vessel itself is proposed for change, the supporting hardware will remain the same. These bioreactors are used for the growth of three-dimensional tissue culture that cannot be done in normal gravity labs. The bioreactors provide a continual supply of oxygen for cell growth, as well as periodic replacement of cell culture media with nutrients. The RWPV has had many successful flights on the space shuttle, but longer duration missions onboard the Mir Space Station resulted in bubbles inside the vessel that were detrimental to the science. It is believed that procedural changes can prevent bubble formation, but the HFB-S must not only provide a mechanism of bubble removal, but must also meet strict requirements for a low-shear environment and uniform oxygen concentration distribution for optimum cell tissue growth. A detailed technical objective (DTO) flight on the space shuttle to fully evaluate the HFB-S is currently in the planning stages. Ground-based activities are also underway to quanitify the characteristics of the HFB-S. Computational studies are being used to predict the internal fluid flow and cell trajectories. These computations will be compared to ground-based flow visualization experiments. Comparative studies of ground-based cell growth between the RWPV and the HFB-S are also in progress. These studies have shown that the HFB-S functions well as a bioreactor in normal gravity. Bubble motion and bubble removal are being studied using computational predictions as well as experimental validation.

  17. The evolution of simulation techniques for dynamic bone tissue engineering in bioreactors.

    PubMed

    Vetsch, Jolanda Rita; Müller, Ralph; Hofmann, Sandra

    2015-08-01

    Bone tissue engineering aims to overcome the drawbacks of current bone regeneration techniques in orthopaedics. Bioreactors are widely used in the field of bone tissue engineering, as they help support efficient nutrition of cultured cells with the possible combination of applying mechanical stimuli. Beneficial influencing parameters of in vitro cultures are difficult to find and are mostly determined by trial and error, which is associated with significant time and money spent. Mathematical simulations can support the finding of optimal parameters. Simulations have evolved over the last 20 years from simple analytical models to complex and detailed computational models. They allow researchers to simulate the mechanical as well as the biological environment experienced by cells seeded on scaffolds in a bioreactor. Based on the simulation results, it is possible to give recommendations about specific parameters for bone bioreactor cultures, such as scaffold geometries, scaffold mechanical properties, the level of applied mechanical loading or nutrient concentrations. This article reviews the evolution in simulating various aspects of dynamic bone culture in bioreactors and reveals future research directions.

  18. 21 CFR 890.1615 - Miniature pressure transducer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Miniature pressure transducer. 890.1615 Section... Miniature pressure transducer. (a) Identification. A miniature pressure transducer is a device intended for medical purposes to measure the pressure between a device and soft tissue by converting mechanical...

  19. 21 CFR 890.1615 - Miniature pressure transducer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Miniature pressure transducer. 890.1615 Section... Miniature pressure transducer. (a) Identification. A miniature pressure transducer is a device intended for medical purposes to measure the pressure between a device and soft tissue by converting mechanical...

  20. 21 CFR 890.1615 - Miniature pressure transducer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Miniature pressure transducer. 890.1615 Section... Miniature pressure transducer. (a) Identification. A miniature pressure transducer is a device intended for medical purposes to measure the pressure between a device and soft tissue by converting mechanical...

  1. Two Views of Islam: Ceramic Tile Design and Miniatures.

    ERIC Educational Resources Information Center

    Macaulay, Sara Grove

    2001-01-01

    Describes an art project focusing on Islamic art that consists of two parts: (1) ceramic tile design; and (2) Islamic miniatures. Provides background information on Islamic art and step-by-step instructions for designing the Islamic tile and miniature. Includes learning objectives and resources on Islamic tile miniatures. (CMK)

  2. Miniature shock tube for laser driven shocks.

    PubMed

    Busquet, Michel; Barroso, Patrice; Melse, Thierry; Bauduin, Daniel

    2010-02-01

    We describe in this paper the design of a miniature shock tube (smaller than 1 cm(3)) that can be placed in a vacuum vessel and allows transverse optical probing and longitudinal backside extreme ultraviolet emission spectroscopy in the 100-500 A range. Typical application is the study of laser launched radiative shocks, in the framework of what is called "laboratory astrophysics."

  3. Miniature Paintings: Small Size, Big Impact!

    ERIC Educational Resources Information Center

    Hicks, Bill

    2011-01-01

    This article describes a miniature painting project that allows students to research a master painter and then replicate the work on a smaller scale. This lesson focuses on the students' ability to learn to identify style, subject matter, themes, and content in painting through the study of historical paintings, and the application of various…

  4. Miniature imaging photometer. Phase 2. Technical report

    SciTech Connect

    Eather, R.H.; Lance, C.A.

    1990-07-15

    Progress is presented in the design and fabrication of a miniature imaging photometer for aurora and airglow studies. Detailed descriptions are presented of present status of optical design and fabrication, detector selection and detector housing fabrication, electronics and control system design and prototyping, selection of image analysis hardware and software, and control software development.

  5. Miniature Housings for Electronics With Standard Interfaces

    NASA Technical Reports Server (NTRS)

    Howard, David E.; Smith, Dennis A.; Alhorn, Dean C.

    2006-01-01

    A family of general-purpose miniature housings has been designed to contain diverse sensors, actuators, and drive circuits plus associated digital electronic readout and control circuits. The circuits contained in the housings communicate with the external world via standard RS-485 interfaces.

  6. Bioreactors in tissue engineering - principles, applications and commercial constraints.

    PubMed

    Hansmann, Jan; Groeber, Florian; Kahlig, Alexander; Kleinhans, Claudia; Walles, Heike

    2013-03-01

    Bioreactor technology is vital for tissue engineering. Usually, bioreactors are used to provide a tissue-specific physiological in vitro environment during tissue maturation. In addition to this most obvious application, bioreactors have the potential to improve the efficiency of the overall tissue-engineering concept. To date, a variety of bioreactor systems for tissue-specific applications have been developed. Of these, some systems are already commercially available. With bioreactor technology, various functional tissues of different types were generated and cultured in vitro. Nevertheless, these efforts and achievements alone have not yet led to many clinically successful tissue-engineered implants. We review possible applications for bioreactor systems within a tissue-engineering process and present basic principles and requirements for bioreactor development. Moreover, the use of bioreactor systems for the expansion of clinically relevant cell types is addressed. In contrast to cell expansion, for the generation of functional three-dimensional tissue equivalents, additional physical cues must be provided. Therefore, bioreactors for musculoskeletal tissue engineering are discussed. Finally, bioreactor technology is reviewed in the context of commercial constraints.

  7. An actively mixed mini-bioreactor for protein production from suspended animal cells.

    PubMed

    Diao, Jinpian; Young, Lincoln; Zhou, Peng; Shuler, Michael Louis

    2008-05-01

    Biopharmaceutical production would benefit from rapid methods to optimize production of therapeutic proteins by screening host cell line/vector combination, culture media, and operational parameters such as timing of induction. Miniaturized bioreactors are an emerging research area aiming at improving the development speed. In this work, a 3 mm thick mini-bioreactor including two 12 mm wide culture chambers connected by a 5 mm wide channel is described. Active mixing is achieved by pressure shuttling between the two chambers. Gas-liquid phase exchange for oxygen and carbon dioxide is realized by molecular diffusion through 50 microm thick polymethylpentene membranes. With this unique design, a velocity difference between the middle area and the side areas at the interfaces of the culture chambers and the connecting channel is created, which enhances the mixing efficiency. The observed mixing time is on the order of 100 s. The combination of high permeability toward oxygen of polymethylpentene membranes and fluid movement during active pressure shuttling enables higher volumetric oxygen transfer coefficients, 5.7 +/- 0.4-14.8 +/- 0.6 h(-1), to be obtained in the mini-bioreactors than the values found in traditional 50 mL spinner flasks, 2.0-2.5 h(-1). Meanwhile, the calculated volume averaged shear stress, in the range of 10(-2)-10(-1) N/m(2), is within the typical tolerable range of animal cells. To demonstrate the applicability of this mini-bioreactor to culture suspended animal cells, the insect cell, Spodoptera frugiperda, is cultured in mini-bioreactors operated under a K(L)a value of 14.8 +/- 0.6 h(-1) and compared to the same cells cultured in 50 mL spinner flasks operated under a K(L)a value of 2.2 h(-1). Sf-21 cells cultured in the mini-bioreactors present comparable length of lag phases and growth rates to their counterparts cultured in 50 mL spinner flasks, but achieve a higher maximum cell density of 5.3 +/- 0.9 x 10(6) cell/mL than the value of 3

  8. Fabrication of a Miniaturized ZnO Nanowire Accelerometer and Its Performance Tests.

    PubMed

    Kim, Hyun Chan; Song, Sangho; Kim, Jaehwan

    2016-01-01

    This paper reports a miniaturized piezoelectric accelerometer suitable for a small haptic actuator array. The accelerometer is made with zinc oxide (ZnO) nanowire (NW) grown on a copper wafer by a hydrothermal process. The size of the accelerometer is 1.5 × 1.5 mm², thus fitting the 1.8 × 1.8 mm² haptic actuator array cell. The detailed fabrication process of the miniaturized accelerometer is illustrated. Performance evaluation of the fabricated accelerometer is conducted by comparing it with a commercial piezoelectric accelerometer. The output current of the fabricated accelerometer increases linearly with the acceleration. The miniaturized ZnO NW accelerometer is feasible for acceleration measurement of small and lightweight devices. PMID:27649184

  9. Fabrication of a Miniaturized ZnO Nanowire Accelerometer and Its Performance Tests

    PubMed Central

    Kim, Hyun Chan; Song, Sangho; Kim, Jaehwan

    2016-01-01

    This paper reports a miniaturized piezoelectric accelerometer suitable for a small haptic actuator array. The accelerometer is made with zinc oxide (ZnO) nanowire (NW) grown on a copper wafer by a hydrothermal process. The size of the accelerometer is 1.5 × 1.5 mm2, thus fitting the 1.8 × 1.8 mm2 haptic actuator array cell. The detailed fabrication process of the miniaturized accelerometer is illustrated. Performance evaluation of the fabricated accelerometer is conducted by comparing it with a commercial piezoelectric accelerometer. The output current of the fabricated accelerometer increases linearly with the acceleration. The miniaturized ZnO NW accelerometer is feasible for acceleration measurement of small and lightweight devices. PMID:27649184

  10. Application of nanotechnology in miniaturized systems and its use in medical and food analysis.

    PubMed

    Kuhlmeier, Dirk; Sandetskaya, Natalia; Allelein, Susann

    2012-12-01

    A combination of Micro-Electro-Mechanical Systems and nanoscale structures allows for the creation of novel miniaturized devices, which broaden the boundaries of the diagnostic approaches. Some materials possess unique properties at the nanolevel, which are different from those in bulk materials. In the last years these properties became a focus of interest for many researchers, as well as methods of production, design and operation of the nanoobjects. Intensive research and development work resulted in numerous inventions, exploiting nanotechnology in miniaturized systems. Modern technical and laboratory equipment allows for the precise control of such devices, making them suitable for sensitive and accurate detection of the analytes. The current review highlights recent patents in the field of nanotechnology in microdevices, applicable for medical and food analysis. The paper covers the structural and functional basis of such systems and describes specific embodiments in three principal branches: application of nanoparticles, nanofluidics, and nanosensors in the miniaturized systems for advanced analytics and diagnostics. PMID:22963075

  11. Nanoparticle separation with a miniaturized asymmetrical flow field-flow fractionation cartridge

    NASA Astrophysics Data System (ADS)

    Müller, David; Cattaneo, Stefano; Meier, Florian; Welz, Roland; deMello, Andrew

    2015-07-01

    Asymmetrical Flow Field-Flow Fractionation (AF4) is a separation technique applicable to particles over a wide size range. Despite the many advantages of AF4, its adoption in routine particle analysis is somewhat limited by the large footprint of currently available separation cartridges, extended analysis times and significant solvent consumption. To address these issues, we describe the fabrication and characterization of miniaturized AF4 cartridges. Key features of the scale-down platform include simplified cartridge and reagent handling, reduced analysis costs and higher throughput capacities. The separation performance of the miniaturized cartridge is assessed using certified gold and silver nanoparticle standards. Analysis of gold nanoparticle populations indicates shorter analysis times and increased sensitivity compared to conventional AF4 separation schemes. Moreover, nanoparticulate titanium dioxide populations exhibiting broad size distributions are analyzed in a rapid and efficient manner. Finally, the repeatability and reproducibility of the miniaturized platform are investigated with respect to analysis time and separation efficiency.

  12. Fabrication of a Miniaturized ZnO Nanowire Accelerometer and Its Performance Tests.

    PubMed

    Kim, Hyun Chan; Song, Sangho; Kim, Jaehwan

    2016-01-01

    This paper reports a miniaturized piezoelectric accelerometer suitable for a small haptic actuator array. The accelerometer is made with zinc oxide (ZnO) nanowire (NW) grown on a copper wafer by a hydrothermal process. The size of the accelerometer is 1.5 × 1.5 mm², thus fitting the 1.8 × 1.8 mm² haptic actuator array cell. The detailed fabrication process of the miniaturized accelerometer is illustrated. Performance evaluation of the fabricated accelerometer is conducted by comparing it with a commercial piezoelectric accelerometer. The output current of the fabricated accelerometer increases linearly with the acceleration. The miniaturized ZnO NW accelerometer is feasible for acceleration measurement of small and lightweight devices.

  13. Circuits and Systems for Low-Power Miniaturized Wireless Sensors

    NASA Astrophysics Data System (ADS)

    Nagaraju, Manohar

    The field of electronic sensors has witnessed a tremendous growth over the last decade particularly with the proliferation of mobile devices. New applications in Internet of Things (IoT), wearable technology, are further expected to fuel the demand for sensors from current numbers in the range of billions to trillions in the next decade. The main challenges for a trillion sensors are continued miniaturization, low-cost and large-scale manufacturing process, and low power consumption. Traditional integration and circuit design techniques in sensor systems are not suitable for applications in smart dust, IoT etc. The first part of this thesis demonstrates an example sensor system for biosignal recording and illustrates the tradeoffs in the design of low-power miniaturized sensors. The different components of the sensor system are integrated at the board level. The second part of the thesis demonstrates fully integrated sensors that enable extreme miniaturization of a sensing system with the sensor element, processing circuitry, a frequency reference for communication and the communication circuitry in a single hermetically sealed die. Design techniques to reduce the power consumption of the sensor interface circuitry at the architecture and circuit level are demonstrated. The principles are used to design sensors for two of the most common physical variables, mass and pressure. A low-power wireless mass and pressure sensor suitable for a wide variety of biological/chemical sensing applications and Tire Pressure Monitoring Systems (TPMS) respectively are demonstrated. Further, the idea of using high-Q resonators for a Voltage Controlled Oscillator (VCO) is proposed and a low-noise, wide bandwidth FBAR-based VCO is presented.

  14. Miniature Scroll Pumps Fabricated by LIGA

    NASA Technical Reports Server (NTRS)

    Wiberg, Dean; Shcheglov, Kirill; White, Victor; Bae, Sam

    2009-01-01

    Miniature scroll pumps have been proposed as roughing pumps (low - vacuum pumps) for miniature scientific instruments (e.g., portable mass spectrometers and gas analyzers) that depend on vacuum. The larger scroll pumps used as roughing pumps in some older vacuum systems are fabricated by conventional machining. Typically, such an older scroll pump includes (1) an electric motor with an eccentric shaft to generate orbital motion of a scroll and (2) conventional bearings to restrict the orbital motion to a circle. The proposed miniature scroll pumps would differ from the prior, larger ones in both design and fabrication. A miniature scroll pump would include two scrolls: one mounted on a stationary baseplate and one on a flexure stage (see figure). An electromagnetic actuator in the form of two pairs of voice coils in a push-pull configuration would make the flexure stage move in the desired circular orbit. The capacitance between the scrolls would be monitored to provide position (gap) feedback to a control system that would adjust the drive signals applied to the voice coils to maintain the circular orbit as needed for precise sealing of the scrolls. To minimize power consumption and maximize precision of control, the flexure stage would be driven at the frequency of its mechanical resonance. The miniaturization of these pumps would entail both operational and manufacturing tolerances of <1 m. Such tight tolerances cannot be achieved easily by conventional machining of high-aspect-ratio structures like those of scroll-pump components. In addition, the vibrations of conventional motors and ball bearings exceed these tight tolerances by an order of magnitude. Therefore, the proposed pumps would be fabricated by the microfabrication method known by the German acronym LIGA ( lithographie, galvanoformung, abformung, which means lithography, electroforming, molding) because LIGA has been shown to be capable of providing the required tolerances at large aspect ratios.

  15. [Optical Design of Miniature Infrared Gratings Spectrometer Based on Planar Waveguide].

    PubMed

    Li, Yang-yu; Fang, Yong-hua; Li, Da-cheng; Liu, Yang

    2015-03-01

    In order to miniaturize an infrared spectrometer, we analyze the current optical design of miniature spectrometers and propose a method for designing a miniature infrared gratings spectrometer based on planar waveguide. Common miniature spectrometer uses miniature optical elements to reduce the size of system, which also shrinks the effective aperture. So the performance of spectrometer has dropped. Miniaturization principle of planar waveguide spectrometer is different from the principle of common miniature spectrometer. In planar waveguide spectrometer, the propagation of light is limited in a thin planar waveguide, which looks like the whole optical system is squashed flat. In the direction parallel to the planar waveguide, the light through the slit is collimated, dispersed and focused. And a spectral image is formed in the detector plane. This propagation of light is similar to the light in common miniature spectrometer. In the direction perpendicular to the planar waveguide, light is multiple reflected by the upper and lower surfaces of the planar waveguide and propagates in the waveguide. So the size of corresponding optical element could be very small in the vertical direction, which can reduce the size of the optical system. And the performance of the spectrometer is still good. The design method of the planar waveguide spectrometer can be separated into two parts, Czerny-Turner structure design and planar waveguide structure design. First, by using aberration theory an aberration-corrected (spherical aberration, coma, focal curve) Czerny-Turner structure is obtained. The operation wavelength range and spectral resolution are also fixed. Then, by using geometrical optics theory a planar waveguide structure is designed for reducing the system size and correcting the astigmatism. The planar waveguide structure includes a planar waveguide and two cylindrical lenses. Finally, they are modeled together in optical design software and are optimized as a whole. An

  16. Hollow fiber bioreactor technology for tissue engineering applications.

    PubMed

    Eghbali, Hadis; Nava, Michele M; Mohebbi-Kalhori, Davod; Raimondi, Manuela T

    2016-01-01

    Hollow fiber bioreactors are the focus of scientific research aiming to mimic physiological vascular networks and engineer organs and tissues in vitro. The reason for this lies in the interesting features of this bioreactor type, including excellent mass transport properties. Indeed, hollow fiber bioreactors allow limitations to be overcome in nutrient transport by diffusion, which is often an obstacle to engineer sizable constructs in vitro. This work reviews the existing literature relevant to hollow fiber bioreactors in organ and tissue engineering applications. To this purpose, we first classify the hollow fiber bioreactors into 2 categories: cylindrical and rectangular. For each category, we summarize their main applications both at the tissue and at the organ level, focusing on experimental models and computational studies as predictive tools for designing innovative, dynamic culture systems. Finally, we discuss future perspectives on hollow fiber bioreactors as in vitro models for tissue and organ engineering applications.

  17. Miniature electron bombardment evaporation source: evaporation rate measurement

    NASA Astrophysics Data System (ADS)

    Nehasil, V.; Mašek, K.; Moreau, O.; Matolín, V.

    1997-03-01

    Miniature electron beam evaporation sources which operate on the principle of vaporization of source material, in the form of a tip, by electron bombardment are produced by several companies specialised in UHV equipment. These sources are used primarily for materials that are normally difficult to deposit due to their high evaporation temperature. They are appropriate for special applications, like heteroepitaxial thin films growth that require very low and well controlled deposition rate. We propose a simple and easily applicable method of evaporation rate control. The method is based on the measurement of ion current produced by electron bombardment of evaporated atoms. In order to be able to determine the ion current - evaporation flux calibration curves we measured the absolute values of evaporation flux by means of Bayard-Alpert ion gauge.

  18. Miniature vibration isolation system for space applications

    NASA Astrophysics Data System (ADS)

    Quenon, Dan; Boyd, Jim; Buchele, Paul; Self, Rick; Davis, Torey; Hintz, Timothy L.; Jacobs, Jack H.

    2001-06-01

    In recent years, there has been a significant interest in, and move towards using highly sensitive, precision payloads on space vehicles. In order to perform tasks such as communicating at extremely high data rates between satellites using laser cross-links, or searching for new planets in distant solar systems using sparse aperture optical elements, a satellite bus and its payload must remain relatively motionless. The ability to hold a precision payload steady is complicated by disturbances from reaction wheels, control moment gyroscopes, solar array drives, stepper motors, and other devices. Because every satellite is essentially unique in its construction, isolating or damping unwanted vibrations usually requires a robust system over a wide bandwidth. The disadvantage of these systems is that they typically are not retrofittable and not tunable to changes in payload size or inertias. Previous work, funded by AFRL, DARPA, BMDO and others, developed technology building blocks that provide new methods to control vibrations of spacecraft. The technology of smart materials enables an unprecedented level of integration of sensors, actuators, and structures; this integration provides the opportunity for new structural designs that can adaptively influence their surrounding environment. To date, several demonstrations have been conducted to mature these technologies. Making use of recent advances in smart materials, microelectronics, Micro-Electro Mechanical Systems (MEMS) sensors, and Multi-Functional Structures (MFS), the Air Force Research Laboratory along with its partner DARPA, have initiated an aggressive program to develop a Miniature Vibration Isolation System (MVIS) (patent pending) for space applications. The MVIS program is a systems-level demonstration of the application of advanced smart materials and structures technology that will enable programmable and retrofittable vibration control of spacecraft precision payloads. The current effort has been awarded

  19. Comparison of Leachate Quality from Aerobic and Anaerobic Municipal Solid Waste Bioreactors

    NASA Astrophysics Data System (ADS)

    Borglin, S. E.; Hazen, T. C.; Oldenburg, C. M.

    2002-12-01

    Municipal solid waste landfills are becoming a drain on the resources of local municipalities as the requirements for stabilization and containment become increasingly stringent. Current regulations limit the moisture in the landfill to minimize leachate production and lower the potential for release of leachate to the environment. Recent research has shown that addition and recycling of moisture in the waste optimizes the biodegradation of stabilization and also provides a means for leachate treatment. This study compares the characteristics of leachate produced from aerobic and anaerobic laboratory bioreactors, and leachate collected from a full-scale anaerobic bioreactor. The laboratory reactors consisted of 200-liter tanks filled with fresh waste materials with the following conditions: (a) aerobic (air injection with leachate recirculation), (b) anaerobic (leachate recirculation). The leachate from the reactors was monitored for metals, nutrients, organic carbon, and microbiological activity for up to 500 days. Leachate from the aerobic tank had significantly lower concentrations of all potential contaminants, both organic and metal, after only a few weeks of operation. Metals leaching was low throughout the test period for the aerobic tanks, and decreased over time for the anaerobic tanks. Organic carbon as measured by BOD, COD, TOC, and COD were an order of magnitude higher in the leachate from the anaerobic system. Microbiological assessment by lipid analysis, enzyme activity assays, and cell counts showed high biomass and diversity in both the aerobic and anaerobic bioreactors, with higher activity in the anaerobic leachate. Results from the full-scale anaerobic bioreactor were not significantly different from those of the laboratory anaerobic bioreactor. The reduction in noxious odors was a significant advantage of the aerobic system. These results suggest that aerobic management of landfills could reduce or eliminate the need for leachate treatment

  20. Miniature Heat Transport System for Nanosatellite Technology

    NASA Technical Reports Server (NTRS)

    Douglas, Donya M,

    1999-01-01

    The scientific understanding of key physical processes between the Sun and the Earth require simultaneous measurements from many vantage points in space. Nano-satellite technologies will enable a class of constellation missions for the NASA Space Science Sun-Earth Connections. This recent emphasis on the implementation of smaller satellites leads to a requirement for development of smaller subsystems in several areas. Key technologies under development include: advanced miniaturized chemical propulsion; miniaturized sensors; highly integrated, compact electronics; autonomous onboard and ground operations; miniatures low power tracking techniques for orbit determination; onboard RF communications capable of transmitting data to the ground from far distances; lightweight efficient solar array panels; lightweight, high output battery cells; lightweight yet strong composite materials for the nano-spacecraft and deployer-ship structures. These newer smaller systems may have higher power densities and higher thermal transport requirements than seen on previous small satellites. Furthermore, the small satellites may also have a requirement to maintain thermal control through extended earth shadows, possibly up to 8 hours long. Older thermal control technology, such as heaters, thermostats, and heat pipes, may not be sufficient to meet the requirements of these new systems. Conversely, a miniature two-phase heat transport system (Mini-HTS) such as a Capillary Pumped Loop (CPL) or Loop Heat Pipe (LBP) is a viable alternative. A Mini-HTS can provide fine temperature control, thermal diode action, and a highly efficient means of heat transfer. The Mini-HTS would have power capabilities in the range of tens of watts or less and provide thermal control over typical spacecraft ranges. The Mini-HTS would allow the internal portion of the spacecraft to be thermally isolated from the external radiator, thus protecting the internal components from extreme cold temperatures during an

  1. FluoSTIC: miniaturized fluorescence image-guided surgery system

    NASA Astrophysics Data System (ADS)

    Gioux, Sylvain; Coutard, Jean-Guillaume; Berger, Michel; Grateau, Henri; Josserand, Véronique; Keramidas, Michelle; Righini, Christian; Coll, Jean-Luc; Dinten, Jean-Marc

    2012-10-01

    Over the last few years, near-infrared (NIR) fluorescence imaging has witnessed rapid growth and is already used in clinical trials for various procedures. However, most clinically compatible imaging systems are optimized for large, open-surgery procedures. Such systems cannot be employed during head and neck oncologic surgeries because the system is not able to image inside deep cavities or allow the surgeon access to certain tumors due to the large footprint of the system. We describe a miniaturized, low-cost, NIR fluorescence system optimized for clinical use during oral oncologic surgeries. The system, termed FluoSTIC, employs a miniature, high-quality, consumer-grade lipstick camera for collecting fluorescence light and a novel custom circular optical fiber array for illumination that combines both white light and NIR excitation. FluoSTIC maintains fluorescence imaging quality similar to that of current large-size imaging systems and is 22 mm in diameter and 200 mm in height and weighs less than 200 g.

  2. FluoSTIC: miniaturized fluorescence image-guided surgery system.

    PubMed

    Gioux, Sylvain; Coutard, Jean-Guillaume; Berger, Michel; Grateau, Henri; Josserand, Véronique; Keramidas, Michelle; Righini, Christian; Coll, Jean-Luc; Dinten, Jean-Marc

    2012-10-01

    Over the last few years, near-infrared (NIR) fluorescence imaging has witnessed rapid growth and is already used in clinical trials for various procedures. However, most clinically compatible imaging systems are optimized for large, open-surgery procedures. Such systems cannot be employed during head and neck oncologic surgeries because the system is not able to image inside deep cavities or allow the surgeon access to certain tumors due to the large footprint of the system. We describe a miniaturized, low-cost, NIR fluorescence system optimized for clinical use during oral oncologic surgeries. The system, termed FluoSTIC, employs a miniature, high-quality, consumer-grade lipstick camera for collecting fluorescence light and a novel custom circular optical fiber array for illumination that combines both white light and NIR excitation. FluoSTIC maintains fluorescence imaging quality similar to that of current large-size imaging systems and is 22 mm in diameter and 200 mm in height and weighs less than 200 g. PMID:23052561

  3. Advanced bioreactors for enhanced production of chemicals

    SciTech Connect

    Davison, B.H.

    1993-12-31

    A variety of advanced bioreactors are being developed to improve production of fuels, solvents, organic acids, and other fermentation products. One key approach is immobilization of the biocatalyst, leading to increased rates and yields. In addition, there are processes for simultaneous fermentation and separation to further increase production. For example, ethanol productivity in immobilized-cell fluidized-bed bioreactors (FBRs) can increase more than tenfold with 99% conversion and near stoichiometric yields. Two modified FBR configurations offer further improvements by removing the inhibitory product directly from the continuous fermentation. One involves the addition and removal of solid adsorbent particles to the FBR. This process was demonstrated with the production of lactic acid by immobilized Lactobacillus. The second uses an immiscible organic extractant in the FBR. This increased total butanol yields in the anaerobic acetone-butanol fermentation by Clostridium acetobutylicum.

  4. The role of bioreactors in tissue engineering.

    PubMed

    Martin, Ivan; Wendt, David; Heberer, Michael

    2004-02-01

    Ex vivo engineering of living tissues is a rapidly developing area with the potential to impact significantly on a wide-range of biomedical applications. Major obstacles to the generation of functional tissues and their widespread clinical use are related to a limited understanding of the regulatory role of specific physicochemical culture parameters on tissue development, and the high manufacturing costs of the few commercially available engineered tissue products. By enabling reproducible and controlled changes of specific environmental factors, bioreactor systems provide both the technological means to reveal fundamental mechanisms of cell function in a 3D environment, and the potential to improve the quality of engineered tissues. In addition, by automating and standardizing tissue manufacture in controlled closed systems, bioreactors could reduce production costs, thus facilitating a wider use of engineered tissues.

  5. Bioreactor-Based Tumor Tissue Engineering

    PubMed Central

    Guller, A.E.; Grebenyuk, P.N.; Shekhter, A.B.; Zvyagin, A.V.; Deyev, S. M.

    2016-01-01

    This review focuses on modeling of cancer tumors using tissue engineering technology. Tumor tissue engineering (TTE) is a new method of three-dimensional (3D) simulation of malignant neoplasms. Design and development of complex tissue engineering constructs (TECs) that include cancer cells, cell-bearing scaffolds acting as the extracellular matrix, and other components of the tumor microenvironment is at the core of this approach. Although TECs can be transplanted into laboratory animals, the specific aim of TTE is the most realistic reproduction and long-term maintenance of the simulated tumor properties in vitro for cancer biology research and for the development of new methods of diagnosis and treatment of malignant neoplasms. Successful implementation of this challenging idea depends on bioreactor technology, which will enable optimization of culture conditions and control of tumor TECs development. In this review, we analyze the most popular bioreactor types in TTE and the emerging applications. PMID:27795843

  6. Chromium detoxification by fixed-film bioreactors

    SciTech Connect

    Chirwa, E.M.N.; Wang, Y.T.

    1996-11-01

    In this study, completely mixed, continuous flow bioreactors were utilized to detoxify chromium. Glass beads were incorporated as a support medium for two strains of bacteria, Bacillus sp. and Pseudomonas fluorescens LB300 (LB300), growing aerobically in two separate reactors. Aerobic conditions were maintained in the reactors by continuously supplying fresh air to the liquid through gas exchange chambers installed on the recycle line of the bioreactors. Results obtained showed that near complete removal of chromate was possible for influent concentrations up to 200 mg/L for Bacillus sp., and up to 100 mg/L for LB300 at 24 hours liquid detention time. Similar results were obtained for corresponding loading rates at 12 hours and 6 hours liquid detention time.

  7. Advanced bioreactors for enhanced production of chemicals

    SciTech Connect

    Davison, B.H.; Scott, C.D.

    1993-06-01

    A variety of advanced bioreactors are being developed to improve production of fuels, solvents, organic acids and other fermentation products. One key approach is immobilization of the biocatalyst leading to increased rates and yields. In addition, there are processes for simultaneous fermentation and separation to further increase production by the removal of an inhibitory product. For example, ethanol productivity in immobilized-cell fluidized-bed bioreactors (FBRs) can increase more than tenfold with 99% conversion and near stoichiometric yields. Two modified FBR configurations offer further improvements by removing the inhibitory product directly from the continuous fermentation. One involves the addition and removal of solid adsorbent particles to the FBR. This process was demonstrated with the production of lactic acid by immobilized Lactobacillus. The second uses an immiscible organic extractant in the FBR. This increased total butanol yields in the anaerobic acetone-butanol fermentation by Clostridium acetobutylicum.

  8. Development of a novel sensor for bioreactor operation

    SciTech Connect

    Huang, B.; Wang, T.W.; Saylor, G. ); Burlage, R. )

    1992-01-01

    For a batch bioreactor operation, the bioluminescence emission profile can be used as an indication for the metabolic state of the cells, because of its high sensitivity to environmental perturbations, such as a change in temperature, pH, the dissolved oxygen level, and inhibitory factors. Among the twelve experiments several qualitative correlation features between the light emission and the biomass growth profiles were observed. However, a consistent quantitative correlation cannot be obtained, mainly because of the inconsistency of the level of emitted light from batch to batch. We are currently trying to control the operation more tightly to see if we,can obtain a more consistent output. However, we plan to switch to the continuous mode of operation, thus controlling the growth to be exponential.

  9. Development of a novel sensor for bioreactor operation

    SciTech Connect

    Huang, B.; Wang, T.W.; Saylor, G.; Burlage, R.

    1992-08-01

    For a batch bioreactor operation, the bioluminescence emission profile can be used as an indication for the metabolic state of the cells, because of its high sensitivity to environmental perturbations, such as a change in temperature, pH, the dissolved oxygen level, and inhibitory factors. Among the twelve experiments several qualitative correlation features between the light emission and the biomass growth profiles were observed. However, a consistent quantitative correlation cannot be obtained, mainly because of the inconsistency of the level of emitted light from batch to batch. We are currently trying to control the operation more tightly to see if we,can obtain a more consistent output. However, we plan to switch to the continuous mode of operation, thus controlling the growth to be exponential.

  10. Design concepts for bioreactors in space

    NASA Technical Reports Server (NTRS)

    Seshan, P. K.; Peterson, G. R.; Beard, B.; Boshe, C.; Dunlop, E. H.

    1987-01-01

    Microbial food sources are becoming viable and more efficient alternatives to conventional food sources, especially in the context of closed ecological life support systems (CELSS) in space habitats. Two bioreactor design concepts presented represent two dissimilar approaches to grappling with the absence of gravity in space habitats and deserve to be tested for adoption as important components of the life support function aboard spacecraft, space stations and other extra-terrestrial habitats.

  11. Oxygen transfer in a pressurized airlift bioreactor.

    PubMed

    Campani, Gilson; Ribeiro, Marcelo Perencin Arruda; Horta, Antônio Carlos Luperni; Giordano, Roberto Campos; Badino, Alberto Colli; Zangirolami, Teresa Cristina

    2015-08-01

    Airlift bioreactors (ALBs) offer advantages over conventional systems, such as simplicity of construction, reduced risk of contamination, and efficient gas-liquid dispersion with low power consumption. ALBs are usually operated under atmospheric pressure. However, in bioprocesses with high oxygen demand, such as high cell density cultures, oxygen limitation may occur even when operating with high superficial gas velocity and air enriched with oxygen. One way of overcoming this drawback is to pressurize the reactor. In this configuration, it is important to assess the influence of bioreactor internal pressure on the gas hold-up, volumetric oxygen transfer coefficient (k(L)a), and volumetric oxygen transfer rate (OTR). Experiments were carried out in a concentric-tube airlift bioreactor with a 5 dm(3) working volume, equipped with a system for automatic monitoring and control of the pressure, temperature, and inlet gas flow rate. The results showed that, in disagreement with previous published results for bubble column and external loop airlift reactors, overpressure did not significantly affect k(L)a within the studied ranges of pressure (0.1-0.4 MPa) and superficial gas velocity in the riser (0.032-0.065 m s(-1)). Nevertheless, a positive effect on OTR was observed: it increased up to 5.4 times, surpassing by 2.3 times the oxygen transfer in a 4 dm(3) stirred tank reactor operated under standard cultivation conditions. These results contribute to the development of non-conventional reactors, especially pneumatic bioreactors operated using novel strategies for oxygen control.

  12. Bioreactor Yields Extracts for Skin Cream

    NASA Technical Reports Server (NTRS)

    2015-01-01

    Johnson Space Flight Center researchers created a unique rotating-wall bioreactor that simulates microgravity conditions, spurring innovations in drug development and medical research. Renuèll Int'l Inc., based in Aventure, Florida, licensed the technology and used it to produce a healing skin care product, RE`JUVEL. In a Food and Drug Administration test, RE`JUVEL substantially increased skin moisture and elasticity while reducing dark blotches and wrinkles.

  13. Miniature instrumentation for laser light scattering experiments

    NASA Technical Reports Server (NTRS)

    Brown, Robert G. W.

    1989-01-01

    Traditional optical systems for photon correlation spectroscopy and laser anemometry have relied upon physically large and fairly expensive lasers, bulk-optics such as lenses of a few inches diameter, large mechanical mounts and carefully selected, fragile and bulky photon counting photomultiplier detectors. In some cases, experimental fluid dynamics at a desired position in a flow, perhaps deep inside complex machinery, is physically impossible or very difficult. Similar problems exist with photon correlation spectroscopy, e.g., remote and heterodyne experiments. Various optical and electro optical components were investigated and characterized with the aim of replacing existing photon correlation laser spectroscopy and anemometry techniques in miniaturized form, and with significant cost reduction. Very recently, a range of miniature, modular light scattering systems were constructed from little solid state optical and electro optical components, and experimentally verified measurement performance comparable to standard lab photon correlation spectroscopy and laser anemometry equipment.

  14. Non-disruptive measurement system of cell viability in bioreactors

    NASA Astrophysics Data System (ADS)

    Rudek, F.; Nelsen, B. L.; Baselt, T.; Berger, T.; Wiele, M.; Prade, I.; Hartmann, P.

    2016-04-01

    Nutrient and oxygen transport, as well as the removal of metabolic waste are essential processes to support and maintain viable tissue. Current bioreactor technology used to grow tissue cultures in vitro has a fundamental limit to the thickness of tissues. Based on the low diffusion limit of oxygen a maximum tissue thickness of 200 μm is possible. The efficiency of those systems is currently under investigation. During the cultivation process of the artificial tissue in bioreactors, which lasts 28 days or longer, there are no possibilities to investigate the viability of cells. This work is designed to determine the influence of a non-disruptive cell viability measuring system on cellular activity. The measuring system uses a natural cellular marker produced during normal metabolic activity. Nicotinamide adenine dinucleotide (NADH) is a coenzyme naturally consumed and produced during cellular metabolic processes and has thoroughly been studied to determine the metabolic state of a cell. Measuring the fluorescence of NADH within the cell represents a non-disruptive marker for cell viability. Since the measurement process is optical in nature, NADH fluorescence also provides a pathway for sampling at different measurement depths within a given tissue sample. The measurement system we are using utilizes a special UV light source, to excite the NADH fluorescence state. However, the high energy potentially alters or harms the cells. To investigate the influence of the excitation signal, the cells were irradiated with a laser operating at a wavelength of 355 nm and examined for cytotoxic effects. The aim of this study was to develop a non-cytotoxic system that is applicable for large-scale operations during drug-tissue interaction testing.

  15. An impact excitation system for repeatable, high-bandwidth modal testing of miniature structures

    NASA Astrophysics Data System (ADS)

    Bediz, Bekir; Korkmaz, Emrullah; Burak Ozdoganlar, O.

    2014-06-01

    Miniature components and devices are increasingly seen in a myriad of applications. In general, the dynamic behavior of miniature devices is critical to their functionality and performance. However, modal testing of miniature structures poses many challenges. This paper presents a design and evaluation of an impact excitation system (IES) for repeatable, high-bandwidth, controlled-force modal testing of miniature structures. Furthermore, a dynamic model of the system is derived and experimentally validated to enable the identification of the system parameters that yield single-hit impacts with desired bandwidth and force magnitude. The system includes a small instrumented impact tip attached to a custom designed flexure-based body, an automated electromagnetic release mechanism, and various precision positioners. The excitation bandwidth and the impact force magnitude can be controlled by selecting the system parameters. The dynamic model of the system includes the structural dynamics of the flexure-based body, the electromagnetic force and the associated eddy-current damping, and the impact event. A validation study showed an excellent match between the model simulations and experiments in terms of impact force and bandwidth. The model is then used to create process maps that relate the system parameters to the number of hits (single vs. multiple), the impact force magnitudes and the excitation bandwidths. These process maps can be used to select system parameters or predict system response for a given set of parameters. A set of experiments is conducted to compare the performances of the IES and a (manual) miniature impact hammer. It is concluded that the IES significantly improves repeatability in terms of the impact bandwidth, location, and force magnitude, while providing a high excitation-bandwidth and excellent coherence values. The application of the IES is demonstrated through modal testing of a miniature contact-probe system.

  16. Raman measurement of glucose in bioreactor materials

    NASA Astrophysics Data System (ADS)

    Xu, Yijing; Ford, Joseph F.; Mann, Charles K.; Vickers, Thomas J.; Brackett, John M.; Cousineau, Kristen L.; Robey, W. G.

    1997-06-01

    The feasibility of using Raman spectroscopy to monitor the concentration of chemical species in a bioreactor has been examined. Successful operation of a bioreactor requires that nutrients and metabolic waste products be maintained within narrow ranges, and it is, therefore, important to provide accurate, reliable and timely measurement of the composition in the reactor. Raman spectroscopy offers the possibility of real time simultaneous monitoring of molecular components present in the millimolar and higher concentration range. Work reported here has focused on four analytes: glucose, glutamine, lactic acid and ammonia. Measurements have been made with a spectrograph providing a spectral window for simultaneous measurement of about 1800 cm-1 on a multichannel CCD detector. Most measurements were made with an argon ion laser emitting at 514.5 nm. Some measurements are reported with a solid state diode laser operating at 785 nm. Locally constructed inexpensive silica fiber-optic probes delivered the laser light and collected the scattered radiation. Spectra of the four analytes n buffer and reactor media have been obtained. Analytical curves have been constructed and limits of detection measured. Limits of detection in buffer media are about 1 mM. Results are reported for off-line measurements on material drawn from a bioreactor.

  17. Replaceable Sensor System for Bioreactor Monitoring

    NASA Technical Reports Server (NTRS)

    Mayo, Mike; Savoy, Steve; Bruno, John

    2006-01-01

    A sensor system was proposed that would monitor spaceflight bioreactor parameters. Not only will this technology be invaluable in the space program for which it was developed, it will find applications in medical science and industrial laboratories as well. Using frequency-domain-based fluorescence lifetime technology, the sensor system will be able to detect changes in fluorescence lifetime quenching that results from displacement of fluorophorelabeled receptors bound to target ligands. This device will be used to monitor and regulate bioreactor parameters including glucose, pH, oxygen pressure (pO2), and carbon dioxide pressure (pCO2). Moreover, these biosensor fluorophore receptor-quenching complexes can be designed to further detect and monitor for potential biohazards, bioproducts, or bioimpurities. Biosensors used to detect biological fluid constituents have already been developed that employ a number of strategies, including invasive microelectrodes (e.g., dark electrodes), optical techniques including fluorescence, and membrane permeable systems based on osmotic pressure. Yet the longevity of any of these sensors does not meet the demands of extended use in spacecraft habitat or bioreactor monitoring. It was therefore necessary to develop a sensor platform that could determine not only fluid variables such as glucose concentration, pO2, pCO2, and pH but can also regulate these fluid variables with controlled feedback loop.

  18. Miniature Reservoir Cathode: An Update

    NASA Technical Reports Server (NTRS)

    Vancil, Bernard K.; Wintucky, Edwin G.

    2002-01-01

    We report on recent work to produce a small low power, low cost reservoir cathode capable of long life (more than 100,000 hours) at high loading (> 5 A/sq cm). Our objective is a highly manufacturable, commercial device costing less than $30. Small highly loaded cathodes are needed, especially for millimeter wave tubes, where focusing becomes difficult when area convergence ratios are too high. We currently have 3 models ranging from .060-inch diameter to. 125-inch diameter. Reservoir type barium dispenser cathodes have a demonstrated capability for simultaneous high emission density and long life. Seven reservoir cathodes continue to operate on the cathode life test facility at NSWC, Crane, Indiana at 2 and 4 amps/sq cm. They have accumulated nearly 100,000 hours with practically no change in emission levels or knee temperature.

  19. Imaging performance of a miniature integrated microendoscope.

    PubMed

    Rogers, Jeremy D; Landau, Sara; Tkaczyk, Tomasz S; Descour, Michael R; Rahman, Mohammed S; Richards-Kortum, Rebecca; Kärkäinen, Ari H O; Christenson, Todd

    2008-01-01

    An integrated miniature multi-modal microscope (4M device) for microendoscopy was built and tested. Imaging performance is evaluated and imaging results are presented for both fluorescence and reflectance samples. Images of biological samples show successful imaging of both thin layers of fixed cells prepared on a slide as well as thick samples of excised fixed porcine epithelial tissue, thus demonstrating the potential for in vivo use.

  20. High Q Miniature Sapphire Acoustic Resonator

    NASA Technical Reports Server (NTRS)

    Wang, Rabi T.; Tjoelker, R. L.

    2010-01-01

    We have demonstrated high Q measurements in a room temperature Miniature Sapphire Acoustic Resonator (MSAR). Initial measurements of bulk acoustic modes in room temperature sapphire at 39 MHz have demonstrated a Q of 8.8 x 10(exp 6). The long term goal of this work is to integrate such a high Q resonator with small, low noise quartz oscillator electronics, providing a fractional frequency stability better than 1 x 10(exp -14) @ 1s.

  1. Miniature Reversal Electron-Attachment Detector

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara

    1994-01-01

    Miniature reversal electron-attachment detector (miniREAD) enables direct injection of air or vapor at atmospheric pressure from monitored area into mass-spectrometric instrument to detect explosives, narcotics, or other substances, vapors of which suspected of being present in low concentrations. In comparison with older reversal electron-attachment detector, miniREAD simpler in design; more rugged; and easier to build, repair, and maintain. In addition, probably more sensitive.

  2. A miniature tilting pad gas lubricated bearing

    NASA Astrophysics Data System (ADS)

    Sixsmith, H.; Swift, W. L.

    1983-12-01

    This paper describes the design and development of a miniature tilting pad gas bearing developed for use in very small turbomachines. The bearings have been developed for cryogenic turboexpanders with shaft diameters down to about 0.3 cm and rotational speeds up to one million rpm. Cryogenic expansion turbines incorporating this type of bearing should be suitable for refrigeration rates down to about 10 w.

  3. A miniature tilting pad gas lubricated bearing

    NASA Technical Reports Server (NTRS)

    Sixsmith, H.; Swift, W. L.

    1983-01-01

    This paper describes the design and development of a miniature tilting pad gas bearing developed for use in very small turbomachines. The bearings have been developed for cryogenic turboexpanders with shaft diameters down to about 0.3 cm and rotational speeds up to one million rpm. Cryogenic expansion turbines incorporating this type of bearing should be suitable for refrigeration rates down to about 10 w.

  4. Raytheon Advanced Miniature Cryocooler Characterization Testing

    NASA Astrophysics Data System (ADS)

    Conrad, T.; Yates, R.; Schaefer, B.; Bellis, L.; Pillar, M.; Barr, M.

    2015-12-01

    The Raytheon Advanced Miniature (RAM) cryocooler is a flight packaged, high frequency pulse tube cooler with an integrated surge volume and inertance tube. Its design has been fully optimized to make use of the Raytheon Advanced Regenerator, resulting in improved efficiency relative to previous Raytheon pulse tube coolers. In this paper, thermodynamic characterization data for the RAM cryocooler is presented along with details of its design specifications.

  5. Micro-Miniature Split Stirling Linear Crycooler

    NASA Astrophysics Data System (ADS)

    Veprik, A.; Zehtzer, S.; Vilenchik, H.; Pundak, N.

    2010-04-01

    Novel tactics for rescue, surveillance, reconnaissance, force protection, perimeter security, navigation and targeting often involve the use of miniature infrared imagers, where the cooled imaging systems are known to be superior to their uncooled rivals in terms of working range, resolution and ability to distinguish/track fast moving objects in dynamic infrared scenes. The latest technological advances in industrial applications of high-temperature infrared detectors have spurred the development of linearly driven, long life, dynamically quiet and aurally undetectable micro-miniature split Stirling linear cryogenic coolers. Recent progress in designing highly efficient "moving magnet" resonant linear actuators and dedicated smart electronics have enabled further improvements to the cooler's size, weight, power consumption, cooldown time and ownership costs. The authors report on the development of a novel micro-miniature split Stirling linear cryogenic cooler, where, by means of increasing the driving frequency up to 90 Hz, it appeared possible to shorten the cold finger to 19 mm. The cooler was specifically designed to cool a new generation of 130 K infrared detectors for portable infrared imagers, where compactness, low steady-state power consumption, fast cool-down time, vibration export and aural stealth are of primary concern.

  6. Fully traceable miniature CMM with submicrometer uncertainty

    NASA Astrophysics Data System (ADS)

    Lewis, Andrew J.

    2003-11-01

    A CMM has been developed which operates over a working volume of 50 × 50 × 50 mm, and achieves an uncertainty in 3D probing of ~100 nm. This miniature CMM is based around the concept of a metrology frame, mounted on a host CMM, with a miniature probe system held on the host CMM's ram. The probing system is rigidly connected to 3 orthogonal mirrors, the positions and rotations of which are measured using 3 dual axis interferometers (length, angle) and 3 dual axis angular sensors. Corrections for the mis-alignments of the interferometers, flatness errors of the mirrors and the performance of the miniature probe system are all determined in situ, by reference to the calibrated laser wavelength. This process performs a full error map of the CMM and requires only two artefacts: a precision sphere and a good quality optical cube. The error map is used online to determine the 3D position of the probe tip, based on measurements of the interferometers and angle sensing systems. The CMM is fully programmable and operates as a normal CMM, albeit with considerably improved accuracy. The design, manufacture and calibration of the CMM are described, followed by examples of measurements made with the machine and a determination of the uncertainty sources. This CMM is designed as the first step in bridging the gap between conventional (millimetre scale metrology) and nanometrology.

  7. Miniature Robotic Spacecraft for Inspecting Other Spacecraft

    NASA Technical Reports Server (NTRS)

    Fredrickson, Steven; Abbott, Larry; Duran, Steve; Goode, Robert; Howard, Nathan; Jochim, David; Rickman, Steve; Straube, Tim; Studak, Bill; Wagenknecht, Jennifer; Lemke, Matthew; Wade, Randall; Wheeler, Scott; Baggerman, Clinton

    2004-01-01

    A report discusses the Miniature Autonomous Extravehicular Robotic Camera (Mini AERCam)-- a compact robotic spacecraft intended to be released from a larger spacecraft for exterior visual inspection of the larger spacecraft. The Mini AERCam is a successor to the AERCam Sprint -- a prior miniature robotic inspection spacecraft that was demonstrated in a space-shuttle flight experiment in 1997. The prototype of the Mini AERCam is a demonstration unit having approximately the form and function of a flight system. The Mini AERCam is approximately spherical with a diameter of about 7.5 in. (.19 cm) and a weight of about 10 lb (.4.5 kg), yet it has significant additional capabilities, relative to the 14-in. (36-cm), 35-lb (16-kg) AERCam Sprint. The Mini AERCam includes miniaturized avionics, instrumentation, communications, navigation, imaging, power, and propulsion subsystems, including two digital video cameras and a high-resolution still camera. The Mini AERCam is designed for either remote piloting or supervised autonomous operations, including station keeping and point-to-point maneuvering. The prototype has been tested on an air-bearing table and in a hardware-in-the-loop orbital simulation of the dynamics of maneuvering in proximity to the International Space Station.

  8. Miniature quadrupole mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1997-01-01

    The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

  9. Miniature quadrupole mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1998-01-01

    The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

  10. Information processing in miniature brains.

    PubMed

    Chittka, L; Skorupski, P

    2011-03-22

    Since a comprehensive understanding of brain function and evolution in vertebrates is often hobbled by the sheer size of the nervous system, as well as ethical concerns, major research efforts have been made to understand the neural circuitry underpinning behaviour and cognition in invertebrates, and its costs and benefits under natural conditions. This special feature of Proceedings of the Royal Society B contains an idiosyncratic range of current research perspectives on neural underpinnings and adaptive benefits (and costs) of such diverse phenomena as spatial memory, colour vision, attention, spontaneous behaviour initiation, memory dynamics, relational rule learning and sleep, in a range of animals from marine invertebrates with exquisitely simple nervous systems to social insects forming societies with many thousands of individuals working together as a 'superorganism'. This introduction provides context and history to tie the various approaches together, and concludes that there is an urgent need to understand the full neuron-to-neuron circuitry underlying various forms of information processing-not just to explore brain function comprehensively, but also to understand how (and how easily) cognitive capacities might evolve in the face of pertinent selection pressures. In the invertebrates, reaching these goals is becoming increasingly realistic.

  11. A novel bioreactor for stimulating skeletal muscle in vitro.

    PubMed

    Donnelly, Kenneth; Khodabukus, Alastair; Philp, Andrew; Deldicque, Louise; Dennis, Robert G; Baar, Keith

    2010-08-01

    For over 300 years, scientists have understood that stimulation, in the form of an electrical impulse, is required for normal muscle function. More recently, the role of specific parameters of the electrical impulse (i.e., the pulse amplitude, pulse width, and work-to-rest ratio) has become better appreciated. However, most existing bioreactor systems do not permit sufficient control over these parameters. Therefore, the aim of the current study was to engineer an inexpensive muscle electrical stimulation bioreactor to apply physiologically relevant electrical stimulation patterns to tissue-engineered muscles and monolayers in culture. A low-powered microcontroller and a DC-DC converter were used to power a pulse circuit that converted a 4.5 V input to outputs of up to 50 V, with pulse widths from 0.05 to 4 ms, and frequencies up to 100 Hz (with certain operational limitations). When two-dimensional cultures were stimulated at high frequencies (100 Hz), this resulted in an increase in the rate of protein synthesis (at 12 h, control [CTL] = 5.0 + or - 0.16; 10 Hz = 5.0 + or - 0.07; and 100 Hz = 5.5 + or - 0.13 fmol/min/mg) showing that this was an anabolic signal. When three-dimensional engineered muscles were stimulated at 0.1 ms and one or two times rheobase, stimulation improved force production (CTL = 0.07 + or - 0.009; 1.25 V/mm = 0.10 + or - 0.011; 2.5 V/mm = 0.14146 + or - 0.012; and 5 V/mm = 0.03756 + or - 0.008 kN/mm(2)) and excitability (CTL = 0.53 + or - 0.022; 1.25 V/mm = 0.44 + or - 0.025; 2.5 V/mm = 0.41 + or - 0.012; and 5 V/mm = 0.60 + or - 0.021 V/mm), suggesting enhanced maturation. Together, these data show that the physiology and function of muscles can be improved in vitro using a bioreactor that allows the control of pulse amplitude, pulse width, pulse frequency, and work-to-rest ratio.

  12. Miniature Sapphire Acoustic Resonator - MSAR

    NASA Technical Reports Server (NTRS)

    Wang, Rabi T.; Tjoelker, Robert L.

    2011-01-01

    A room temperature sapphire acoustics resonator incorporated into an oscillator represents a possible opportunity to improve on quartz ultrastable oscillator (USO) performance, which has been a staple for NASA missions since the inception of spaceflight. Where quartz technology is very mature and shows a performance improvement of perhaps 1 dB/decade, these sapphire acoustic resonators when integrated with matured quartz electronics could achieve a frequency stability improvement of 10 dB or more. As quartz oscillators are an essential element of nearly all types of frequency standards and reference systems, the success of MSAR would advance the development of frequency standards and systems for both groundbased and flight-based projects. Current quartz oscillator technology is limited by quartz mechanical Q. With a possible improvement of more than x 10 Q with sapphire acoustic modes, the stability limit of current quartz oscillators may be improved tenfold, to 10(exp -14) at 1 second. The electromagnetic modes of sapphire that were previously developed at JPL require cryogenic temperatures to achieve the high Q levels needed to achieve this stability level. However sapphire fs acoustic modes, which have not been used before in a high-stability oscillator, indicate the required Q values (as high as Q = 10(exp 8)) may be achieved at room temperature in the kHz range. Even though sapphire is not piezoelectric, such a high Q should allow electrostatic excitation of the acoustic modes with a combination of DC and AC voltages across a small sapphire disk (approximately equal to l mm thick). The first evaluations under this task will test predictions of an estimated input impedance of 10 kilohms at Q = 10(exp 8), and explore the Q values that can be realized in a smaller resonator, which has not been previously tested for acoustic modes. This initial Q measurement and excitation demonstration can be viewed similar to a transducer converting electrical energy to

  13. Correlation between mass transfer coefficient kLa and relevant operating parameters in cylindrical disposable shaken bioreactors on a bench-to-pilot scale

    PubMed Central

    2013-01-01

    Background Among disposable bioreactor systems, cylindrical orbitally shaken bioreactors show important advantages. They provide a well-defined hydrodynamic flow combined with excellent mixing and oxygen transfer for mammalian and plant cell cultivations. Since there is no known universal correlation between the volumetric mass transfer coefficient for oxygen kLa and relevant operating parameters in such bioreactor systems, the aim of this current study is to experimentally determine a universal kLa correlation. Results A Respiration Activity Monitoring System (RAMOS) was used to measure kLa values in cylindrical disposable shaken bioreactors and Buckingham’s π-Theorem was applied to define a dimensionless equation for kLa. In this way, a scale- and volume-independent kLa correlation was developed and validated in bioreactors with volumes from 2 L to 200 L. The final correlation was used to calculate cultivation parameters at different scales to allow a sufficient oxygen supply of tobacco BY-2 cell suspension cultures. Conclusion The resulting equation can be universally applied to calculate the mass transfer coefficient for any of seven relevant cultivation parameters such as the reactor diameter, the shaking frequency, the filling volume, the viscosity, the oxygen diffusion coefficient, the gravitational acceleration or the shaking diameter within an accuracy range of +/− 30%. To our knowledge, this is the first kLa correlation that has been defined and validated for the cited bioreactor system on a bench-to-pilot scale. PMID:24289110

  14. Miniaturized passive hydrogel check valve for hydrocephalus treatment.

    PubMed

    Schwerdt, Helen N; Bristol, Ruth E; Junseok Chae

    2014-03-01

    Improvements in cerebrospinal fluid (CSF) draining techniques for treatment of hydrocephalus are urgently sought after to substitute for current CSF shunts that are plagued by high failure rates. The passive check valve aims to restore near natural CSF draining operations while mitigating possible failure mechanisms caused by finite leakage or low resilience that frequently constrain practical implementation of miniaturized valves. A simple hydrogel diaphragm structures core passive valve operations and enforce valve sealing properties to substantially lower reverse flow leakage. Experimental measurements demonstrate realization of targeted cracking pressures (PT ≈ 20-110 mmH2O) and operation at -800 <; ΔP <; 600 mmH2O without observable degradation or leakage.

  15. In vivo demonstration of surgical task assistance using miniature robots.

    PubMed

    Hawks, Jeff A; Kunowski, Jacob; Platt, Stephen R

    2012-10-01

    Laparoscopy is beneficial to patients as measured by less painful recovery and an earlier return to functional health compared to conventional open surgery. However, laparoscopy requires the manipulation of long, slender tools from outside the patient's body. As a result, laparoscopy generally benefits only patients undergoing relatively simple procedures. An innovative approach to laparoscopy uses miniature in vivo robots that fit entirely inside the abdominal cavity. Our previous work demonstrated that a mobile, wireless robot platform can be successfully operated inside the abdominal cavity with different payloads (biopsy, camera, and physiological sensors). We hope that these robots are a step toward reducing the invasiveness of laparoscopy. The current study presents design details and results of laboratory and in vivo demonstrations of several new payload designs (clamping, cautery, and liquid delivery). Laboratory and in vivo cooperation demonstrations between multiple robots are also presented. PMID:22893373

  16. Miniaturized module for the wireless transmission of measurements with Bluetooth.

    PubMed

    Roth, H; Schwaibold, M; Moor, C; Schöchlin, J; Bolz, A

    2002-01-01

    The wiring of patients for obtaining medical measurements has many disadvantages. In order to limit these, a miniaturized module was developed which digitalizes analog signals and sends the signal wirelessly to the receiver using Bluetooth. Bluetooth is especially suitable for this application because distances of up to 10 m are possible with low power consumption and robust transmission with encryption. The module consists of a Bluetooth chip, which is initialized in such a way by a microcontroller that connections from other bluetooth receivers can be accepted. The signals are then transmitted to the distant end. The maximum bit rate of the 23 mm x 30 mm module is 73.5 kBit/s. At 4.7 kBit/s, the current consumption is 12 mA.

  17. In vivo demonstration of surgical task assistance using miniature robots.

    PubMed

    Hawks, Jeff A; Kunowski, Jacob; Platt, Stephen R

    2012-10-01

    Laparoscopy is beneficial to patients as measured by less painful recovery and an earlier return to functional health compared to conventional open surgery. However, laparoscopy requires the manipulation of long, slender tools from outside the patient's body. As a result, laparoscopy generally benefits only patients undergoing relatively simple procedures. An innovative approach to laparoscopy uses miniature in vivo robots that fit entirely inside the abdominal cavity. Our previous work demonstrated that a mobile, wireless robot platform can be successfully operated inside the abdominal cavity with different payloads (biopsy, camera, and physiological sensors). We hope that these robots are a step toward reducing the invasiveness of laparoscopy. The current study presents design details and results of laboratory and in vivo demonstrations of several new payload designs (clamping, cautery, and liquid delivery). Laboratory and in vivo cooperation demonstrations between multiple robots are also presented.

  18. Chemically modified graphene based supercapacitors for flexible and miniature devices

    NASA Astrophysics Data System (ADS)

    Ghosh, Debasis; Kim, Sang Ouk

    2015-09-01

    Rapid progress in the portable and flexible electronic devises has stimulated supercapacitor research towards the design and fabrication of high performance flexible devices. Recent research efforts for flexible supercapacitor electrode materials are highly focusing on graphene and chemically modified graphene owing to the unique properties, including large surface area, high electrical and thermal conductivity, excellent mechanical flexibility, and outstanding chemical stability. This invited review article highlights current status of the flexible electrode material research based on chemically modified graphene for supercapacitor application. A variety of electrode architectures prepared from chemically modified graphene are summarized in terms of their structural dimensions. Novel prototypes for the supercapacitor aiming at flexible miniature devices, i.e. microsupercapacitor with high energy and power density are highlighted. Future challenges relevant to graphene-based flexible supercapacitors are also suggested. [Figure not available: see fulltext.

  19. ADVANCING THE FIELD EVALUATIONS AND APPLICATIONS OF LANDFILL BIOREACTORS

    EPA Science Inventory

    The US Environmental Protection Agency (EPA) is undertaking a long-term program to conduct field evaluations of landfill bioreactors. The near-term effort is focused on the development of appropriate monitoring strategies to ensure adequate control of the landfill bioreactors an...

  20. Microbial community analysis of a full-scale DEMON bioreactor.

    PubMed

    Gonzalez-Martinez, Alejandro; Rodriguez-Sanchez, Alejandro; Muñoz-Palazon, Barbara; Garcia-Ruiz, Maria-Jesus; Osorio, Francisco; van Loosdrecht, Mark C M; Gonzalez-Lopez, Jesus

    2015-03-01

    Full-scale applications of autotrophic nitrogen removal technologies for the treatment of digested sludge liquor have proliferated during the last decade. Among these technologies, the aerobic/anoxic deammonification process (DEMON) is one of the major applied processes. This technology achieves nitrogen removal from wastewater through anammox metabolism inside a single bioreactor due to alternating cycles of aeration. To date, microbial community composition of full-scale DEMON bioreactors have never been reported. In this study, bacterial community structure of a full-scale DEMON bioreactor located at the Apeldoorn wastewater treatment plant was analyzed using pyrosequencing. This technique provided a higher-resolution study of the bacterial assemblage of the system compared to other techniques used in lab-scale DEMON bioreactors. Results showed that the DEMON bioreactor was a complex ecosystem where ammonium oxidizing bacteria, anammox bacteria and many other bacterial phylotypes coexist. The potential ecological role of all phylotypes found was discussed. Thus, metagenomic analysis through pyrosequencing offered new perspectives over the functioning of the DEMON bioreactor by exhaustive identification of microorganisms, which play a key role in the performance of bioreactors. In this way, pyrosequencing has been proven as a helpful tool for the in-depth investigation of the functioning of bioreactors at microbiological scale.

  1. Evaluation of woodchip bioreactors for improved water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Woodchip bioreactors are gaining popularity with farmers because of their edge-of-field nitrate removal capabilities, which do not require changes in land management practices. However, limited research has been conducted to study the potential of these bioreactors to also reduce downstream transpor...

  2. Denitrifying bioreactors for nitrate removal from tile drained cropland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Denitrification bioreactors are a promising technology for mitigation of nitrate-nitrogen (NO3-N) losses in subsurface drainage water. Bioreactors are constructed with carbon substrates, typically wood chips, to provide a substrate for denitrifying microorganisms. Researchers in Iowa found that for ...

  3. A miniature quantitative PCR device for directly monitoring a sample processing on a microfluidic rapid DNA system.

    PubMed

    Hurth, Cedric; Yang, Jianing; Barrett, Matthew; Brooks, Carla; Nordquist, Alan; Smith, Stanley; Zenhausern, Frederic

    2014-12-01

    We report a microfluidic device and measurement method to perform real-time PCR (or qPCR) in a miniaturized configuration for on-chip implementation using reaction volumes of less than 20 μL. The qPCR bioreactor is designed as a module to be embedded in an automated sample-in/profile-out system for rapid DNA biometrics or human identification. The PCR mixture is excited with a 505 nm diode-pumped solid-state laser (DPSSL) and the fluorescence build-up is measured using optical fibers directly embedded to the sidewalls of the microfluidic qPCR bioreactor. We discuss manufacturing and operating parameters necessary to adjust the internal surface conditions and temperature profiles of the bioreactor and to optimize the yield and quality of the PCR reaction for the amplification of 62 bp hTERT intron fragments using the commercial Quantifiler® kit (Life Technologies, Carlsbad, CA) commonly accepted for genotyping analysis. We designed a microfluidic device suitable for continuously processing a specimen by efficiently mixing the reagents from the kit to a set volume of DNA template on chip. Our approach relies on a calibration curve for the specific device using control DNA. We successfully applied this method to determine the concentration of genomic DNA extracted from a buccal swab on separate microfluidic devices which are operated upstream the qPCR device and perform buccal swab lysis and buccal DNA extraction. A precise correlation between the amount determined on chip and that obtained using a commercial cycler is demonstrated.

  4. Novel micro-bioreactor high throughput technology for cell culture process development: Reproducibility and scalability assessment of fed-batch CHO cultures.

    PubMed

    Amanullah, Ashraf; Otero, Jose Manuel; Mikola, Mark; Hsu, Amy; Zhang, Jinyou; Aunins, John; Schreyer, H Brett; Hope, James A; Russo, A Peter

    2010-05-01

    With increasing timeline pressures to get therapeutic and vaccine candidates into the clinic, resource intensive approaches such as the use of shake flasks and bench-top bioreactors may limit the design space for experimentation to yield highly productive processes. The need to conduct large numbers of experiments has resulted in the use of miniaturized high-throughput (HT) technology for process development. One such high-throughput system is the SimCell platform, a robotically driven, cell culture bioreactor system developed by BioProcessors Corp. This study describes the use of the SimCell micro-bioreactor technology for fed-batch cultivation of a GS-CHO transfectant expressing a model IgG4 monoclonal antibody. Cultivations were conducted in gas-permeable chambers based on a micro-fluidic design, with six micro-bioreactors (MBs) per micro-bioreactor array (MBA). Online, non-invasive measurement of total cell density, pH and dissolved oxygen (DO) was performed. One hundred fourteen parallel MBs (19 MBAs) were employed to examine process reproducibility and scalability at shake flask, 3- and 100-L bioreactor scales. The results of the study demonstrate that the SimCell platform operated under fed-batch conditions could support viable cell concentrations up to least 12 x 10(6) cells/mL. In addition, both intra-MB (MB to MB) as well as intra-MBA (MBA to MBA) culture performance was found to be highly reproducible. The intra-MB and -MBA variability was calculated for each measurement as the coefficient of variation defined as CV (%) = (standard deviation/mean) x 100. The % CV values for most intra-MB and intra-MBA measurements were generally under 10% and the intra-MBA values were slightly lower than those for intra-MB. Cell growth, process parameters, metabolic and protein titer profiles were also compared to those from shake flask, bench-top, and pilot scale bioreactor cultivations and found to be within +/-20% of the historical averages.

  5. STATE OF THE PRACTICE FOR BIOREACTOR LANDFILLS - SUMMARY OF USEPA WORKSHOP ON BIOREACTOR LANDFILLS: SUMMARY

    EPA Science Inventory

    This is a summary of the Workshop on Landfill Bioreactors, held 9/6-7/2000 in Arlington, VA. The purpose of the workshop was to provide a forum to EPA, state and local governments, solid waste industry, and academic research representatives to exchange information and ideas on b...

  6. Performance of an anaerobic, static bed, fixed film bioreactor for chlorinated solvent treatment

    USGS Publications Warehouse

    Lorah, Michelle M.; Walker, Charles; Graves, Duane

    2015-01-01

    Anaerobic, fixed film, bioreactors bioaugmented with a dechlorinating microbial consortium were evaluated as a potential technology for cost effective, sustainable, and reliable treatment of mixed chlorinated ethanes and ethenes in groundwater from a large groundwater recovery system. Bench- and pilot-scale testing at about 3 and 13,500 L, respectively, demonstrated that total chlorinated solvent removal to less than the permitted discharge limit of 100 μg/L. Various planned and unexpected upsets, interruptions, and changes demonstrated the robustness and reliability of the bioreactor system, which handled the operational variations with no observable change in performance. Key operating parameters included an adequately long hydraulic retention time for the surface area, a constant supply of electron donor, pH control with a buffer to minimize pH variance, an oxidation reduction potential of approximately −200 millivolts or lower, and a well-adapted biomass capable of degrading the full suite of chlorinated solvents in the groundwater. Results indicated that the current discharge criteria can be met using a bioreactor technology that is less complex and has less downtime than the sorption based technology currently being used to treat the groundwater.

  7. Performance of an anaerobic, static bed, fixed film bioreactor for chlorinated solvent treatment.

    PubMed

    Lorah, Michelle M; Walker, Charles; Graves, Duane

    2015-09-01

    Anaerobic, fixed film, bioreactors bioaugmented with a dechlorinating microbial consortium were evaluated as a potential technology for cost effective, sustainable, and reliable treatment of mixed chlorinated ethanes and ethenes in groundwater from a large groundwater recovery system. Bench- and pilot-scale testing at about 3 and 13,500 L, respectively, demonstrated that total chlorinated solvent removal to less than the permitted discharge limit of 100 μg/L. Various planned and unexpected upsets, interruptions, and changes demonstrated the robustness and reliability of the bioreactor system, which handled the operational variations with no observable change in performance. Key operating parameters included an adequately long hydraulic retention time for the surface area, a constant supply of electron donor, pH control with a buffer to minimize pH variance, an oxidation reduction potential of approximately -200 millivolts or lower, and a well-adapted biomass capable of degrading the full suite of chlorinated solvents in the groundwater. Results indicated that the current discharge criteria can be met using a bioreactor technology that is less complex and has less downtime than the sorption based technology currently being used to treat the groundwater.

  8. Disposable bioreactors for inoculum production and protein expression.

    PubMed

    Eibl, Regine; Löffelholz, Christian; Eibl, Dieter

    2014-01-01

    Disposable bioreactors have been increasingly implemented over the past ten years. This relates to both R & D and commercial manufacture, in particular, in animal cell-based processes. Among the numerous disposable bioreactors which are available today, wave-mixed bag bioreactors and stirred bioreactors are predominant. Whereas wave-mixed bag bioreactors represent the system of choice for inoculum production, stirred systems are often preferred for protein expression. For this reason, the authors present protocols instructing the reader how to use the wave-mixed BIOSTAT CultiBag RM 20 L for inoculum production and the stirred UniVessel SU 2 L for recombinant protein production at benchtop scale. All methods described are based on a Chinese hamster ovary (CHO) suspension cell line expressing the human placental secreted alkaline phosphatase (SEAP).

  9. Reduced-Gravity Experiments Conducted to Help Bioreactor Development

    NASA Technical Reports Server (NTRS)

    Niederhaus, Charles E.; Nahra, Henry K.; Kizito, John P.

    2004-01-01

    The NASA Glenn Research Center and the NASA Johnson Space Center are collaborating on fluid dynamic investigations for a future cell science bioreactor to fly on the International Space Station (ISS). Project Manager Steven Gonda from the Cellular Biotechnology Program at Johnson is leading the development of the Hydrodynamic Focusing Bioreactor--Space (HFB-S) for use on the ISS to study tissue growth in microgravity. Glenn is providing microgravity fluid physics expertise to help with the design and evaluation of the HFB-S. These bioreactors are used for three-dimensional tissue culture, which cannot be done in ground-based labs in normal gravity. The bioreactors provide a continual supply of oxygen for cell growth, as well as periodic replacement of cell culture media with nutrients. The bioreactor must provide a uniform distribution of oxygen and nutrients while minimizing the shear stresses on the tissue culture.

  10. Development of Californium-252 Miniature Source Assemblies

    SciTech Connect

    Notspecified, N. A.

    2007-06-26

    The purpose of this CRADA between ORNL and lsotron, Inc. is to develop miniature californium-252 sources configured for remote handling that can be used in neutron brachytherapy for treatment of cancer. Brachytherapy places the · radioactive source at or near the site of the tumor, using a catheter. The CRADA ran from late 1999 through November 2005. The heart of a Cf-252 source is the radioactive core wire, which is sealed inside a metallic source capsule. Previous Cf-252 medical sources were based on a cermet wire with californium oxide dispersed in palladium, typically >1-mm diameter and <0.1% Cf-252 by weight. Previously, the standard medical source in the U.S. was the Applicator Tube (AT) source. 23-mm long, 2.8-mm diameter, with ~30 {micro}g of Cf-252, and which required manual loading into patients by medical staff. The goal of this work was to develop capabilities and technology to fabricate higher-intensity Cf-252 sources attached to a positioning cable, with overall diameter approaching that of exist ing photon (iridium-192) brachytherapy sources (i.e., ~1.1 mm). This work was successful in developing and demonstrating new technologies and procedures for the fabrication of miniaturized Cf-252 sources. CRADA-designed equipment reduced the wire diameters significantly (patent pending). Short wire segments were cut and successfully welded inside capsules meeting the miniaturization goals. A batch of seven prototype sources was prepared that met fabrication specifications. Although their neutron emissions were not maximized, they were still several times more intense than the previous AT sources. Very robust source-to-cable attachment methods were demonstrated (patent issued). A shipping canister was designed and built to contain the completed source assembly. lsotron designed and built a computer-controlled remote afterloader system to deliver the new sources for treatments.

  11. Miniaturized Mid-Infrared Sensor Technologies

    SciTech Connect

    Kim, S; Young, C; Mizaikoff, B

    2007-08-16

    Fundamental vibrational and rotational modes associated with most inorganic and organic molecules are spectroscopically accessible within the mid-infrared (MIR; 3-20 {micro}m) regime of the electromagnetic spectrum. The interaction between MIR photons and organic molecules provides particularly sharp transitions, which - despite the wide variety of organic molecules - provide unique MIR absorption spectra reflecting the molecularly characteristic arrangement of chemical bonds within the probed molecules via the frequency position of the associated vibrational and rotational transitions. Given the inherent molecular selectivity and achievable sensitivity, MIR spectroscopy provides an ideal platform for optical sensing applications. Despite this potential, early MIR sensing applications were limited to localized applications due to the size of the involved instrumentation, and limited availability of appropriately compact MIR optical components including light sources, detectors, waveguides, and spectrometers. During the last decades, engineering advances in photonics and optical engineering have facilitated the translation of benchtop-style MIR spectroscopy into miniaturized optical sensing schemes providing a footprint compatible with portable instrumentation requirements for field deployable analytical tools. In this trend article, we will discuss recent advances and future strategies for miniaturizing MIR sensor technology. The Beer-Lambert law implies that achievable limit of detection (LOD) for any optical sensor system improves by increasing the interaction length between photons and target analyte species such as e.g., folding the optical path multiple times as in multi-pass gas phase sensing; however, this governing paradigm naturally leads to an increase in system dimensions. Hence, miniaturization of optical sensing system requires scaling down of each optical component, yet improving the performance of each optical element within a smaller form factor for

  12. Tissue grown in space in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. Final samples from Mir and Earth appeared histologically cartilaginous throughout their entire cross sections (5-8 mm thick), with the exception of fibrous outer capsules. Constructs grown on Earth (A) appeared to have a more organized extracellular matrix with more uniform collagen orientation as compared with constructs grown on Mir (B), but the average collagen fiber diameter was similar in the two groups (22 +- 2 nm) and comparable to that previously reported for developing articular cartilage. Randomly oriented collagen in Mir samples would be consistent with previous reports that microgravity disrupts fibrillogenesis. These are transmission electron micrographs of constructs from Mir (A) and Earth (B) groups at magnifications of x3,500 and x120,000 (Inset). The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Credit: Proceedings of the National Academy of Sciences.

  13. Rad-Hard, Miniaturized, Scalable, High-Voltage Switching Module for Power Applications Rad-Hard, Miniaturized

    NASA Technical Reports Server (NTRS)

    Adell, Philippe C.; Mojarradi, Mohammad; DelCastillo, Linda Y.; Vo, Tuan A.

    2011-01-01

    A paper discusses the successful development of a miniaturized radiation hardened high-voltage switching module operating at 2.5 kV suitable for space application. The high-voltage architecture was designed, fabricated, and tested using a commercial process that uses a unique combination of 0.25 micrometer CMOS (complementary metal oxide semiconductor) transistors and high-voltage lateral DMOS (diffusion metal oxide semiconductor) device with high breakdown voltage (greater than 650 V). The high-voltage requirements are achieved by stacking a number of DMOS devices within one module, while two modules can be placed in series to achieve higher voltages. Besides the high-voltage requirements, a second generation prototype is currently being developed to provide improved switching capabilities (rise time and fall time for full range of target voltages and currents), the ability to scale the output voltage to a desired value with good accuracy (few percent) up to 10 kV, to cover a wide range of high-voltage applications. In addition, to ensure miniaturization, long life, and high reliability, the assemblies will require intensive high-voltage electrostatic modeling (optimized E-field distribution throughout the module) to complete the proposed packaging approach and test the applicability of using advanced materials in a space-like environment (temperature and pressure) to help prevent potential arcing and corona due to high field regions. Finally, a single-event effect evaluation would have to be performed and single-event mitigation methods implemented at the design and system level or developed to ensure complete radiation hardness of the module.

  14. Compact and miniature snapshot imaging polarimeter.

    PubMed

    Luo, Haitao; Oka, Kazuhiko; DeHoog, Edward; Kudenov, Michael; Schiewgerling, James; Dereniak, Eustace L

    2008-08-20

    We present and demonstrate a compact and miniature snapshot imaging polarimeter camera; it is anticipated that such a camera can be scaled down to less than 1.5 cm. Two Savart plates are used at the pupil plane to generate multiple fringes to encode the full Stokes vector in a single image. A geometric ray model is developed to explain the system. The numerical simulation based on this model is presented. Finally, the validity of the device is demonstrated by showing experimental results. PMID:18716648

  15. Miniature Ground Penetrating Radar, CRUX GPR

    NASA Technical Reports Server (NTRS)

    Kim, Soon Sam; Carnes, Steven R.; Haldemann, Albert F.; Ulmer, Christopher T.; Ng, Eddie; Arcone, Steven A.

    2006-01-01

    Under NASA instrument development programs (PIDDP 2000-2002, MIPD 2003-2005, ESR and T, 2005) we have been developing miniature ground penetrating radars (GPR) for use in mapping subsurface stratigraphy from planetary rovers for Mars and lunar applications. The Mars GPR is for deeper penetration (up to 50 m depth) into the Martian subsurface at moderate resolution (0.5 m) for a geological characterization. As a part of the CRUX (Construction and Resource Utilization Explorer) instrument suite, the CRUX GPR is optimized for a lunar prospecting application. It will have shallower penetration (5 m depth) with higher resolution (10 cm) for construction operations including ISRU (in-situ resource utilization).

  16. Miniature Robotic Submarine for Exploring Harsh Environments

    NASA Technical Reports Server (NTRS)

    Behar, Alberto; Bruhn, Fredrik; Carsey, Frank

    2004-01-01

    The miniature autonomous submersible explorer (MASE) has been proposed as a means of scientific exploration -- especially, looking for signs of life -- in harsh, relatively inaccessible underwater environments. Basically, the MASE would be a small instrumented robotic submarine (see figure) that could launch itself or could be launched from another vehicle. Examples of environments that might be explored by use of the MASE include subglacial lakes, deep-ocean hydrothermal vents, acidic or alkaline lakes, brine lenses in permafrost, and ocean regions under Antarctic ice shelves.

  17. A miniature solid propellant rocket motor

    SciTech Connect

    Grubelich, M.C.; Hagan, M.; Mulligan, E.

    1997-08-01

    A miniature solid-propellant rocket motor has been developed to impart a specific motion to an object deployed in space. This rocket motor effectively eliminated the need for a cold-gas thruster system or mechanical spin-up system. A low-energy igniter, an XMC4397, employing a semiconductor bridge was used to ignite the rocket motor. The rocket motor was ground-tested in a vacuum tank to verify predicted space performance and successfully flown in a Sandia National Laboratories flight vehicle program.

  18. Miniature integrated-optical wavelength analyzer chip

    NASA Astrophysics Data System (ADS)

    Kunz, R. E.; Dübendorfer, J.

    1995-11-01

    A novel integrated-optical chip suitable for realizing compact miniature wavelength analyzers with high linear dispersion is presented. The chip performs the complete task of converting the spectrum of an input beam into a corresponding spatial irradiance distribution without the need for an imaging function. We demonstrate the feasibility of this approach experimentally by monitoring the changes in the mode spectrum of a laser diode on varying its case temperature. Comparing the results with simultaneous measurements by a commercial spectrometer yielded a rms wavelength deviation of 0.01 nm.

  19. Miniature interferometer terminals for earth surveying

    NASA Technical Reports Server (NTRS)

    Counselman, C. C., III; Shapiro, I. I.

    1978-01-01

    A system of miniature radio interferometer terminals was proposed for the measurement of vector baselines with uncertainties ranging from the millimeter to the centimeter level for baseline lengths ranging, respectively, from a few to a few hundred kilometers. Each terminal would have no moving parts, could be packaged in a volume of less than 0.1 cu m, and would operate unattended. These units would receive radio signals from low-power (10 w) transmitters on earth-orbiting satellites. The baselines between units could be determined virtually instantaneously and monitored continuously as long as at least four satellites were visible simultaneously.

  20. Miniaturized bendable 400 MHz artificial magnetic conductor

    NASA Astrophysics Data System (ADS)

    Presse, Anthony; Tarot, Anne-Claude

    2016-04-01

    A bendable artificial magnetic conductor (AMC) with a resonant frequency of 400 MHz is proposed. The dimensions of the unit cell are 50 × 50 mm2 or 0.07 × 0.07 λ0. The miniaturization is achieved with closely coupled patches printed on each side of a 0.127-mm-thick dielectric substrate. This last one is stacked on a flexible 3-mm-thick silicone over a ground plane. An AMC prototype is simulated and manufactured. Also, a printed inverted-F antenna is used to highlight the bandwidth of the AMC.

  1. Bioreactor boats high BTEX removal rate

    SciTech Connect

    Hickey, R.

    1994-04-01

    The oil and gas industries face formidable challenges in treating process wastes to federally mandated standards. The sheer magnitude of the job is daunting: 1,200 Superfund sites and 11,000 military installations have been identified for toxic cleanup. EPA assessments place petroleum as the point source of contamination for fully 50 percent of all identified hazardous waste sites. A new treatment technolgy is a fluidized-bed bioreactor that combines the advantages of a physical carbon adsorption system with bioremediation. The system has been effective in treating tank botton wastes, brines, groundwater contaminated with benzene, toluene, xylene, aliphatic hydrocarbons, and polycyclic aromatic hydrocarbons.

  2. Autonomous chemical and biological miniature wireless-sensor

    NASA Astrophysics Data System (ADS)

    Goldberg, Bar-Giora

    2005-05-01

    would take place within the miniature, low cost distributed sensor platforms. This concept however presents a significant challenge due to a combination and convergence of required new technologies, as mentioned above. Passive biological and chemical sensors with very high sensitivity and which require no assaying are in development using a technique to optically and chemically encode silicon wafers with tailored nanostructures. The silicon wafer is patterned with nano-structures designed to change colors ad patterns when exposed to the target analytes (TICs, TIMs, VOC). A small video camera detects the color and pattern changes on the sensor. To determine if an alarm condition is present, an on board DSP processor, using specialized image processing algorithms and statistical analysis, determines if color gradient changes occurred on the sensor array. These sensors can detect several agents simultaneously. This system is currently under development by Avaak, with funding from DARPA through an SBIR grant.

  3. Dual-Purpose Bioreactors to Monitor Noninvasive Physical and Biochemical Markers of Kidney and Liver Scaffold Recellularization

    PubMed Central

    Uzarski, Joseph S.; Bijonowski, Brent M.; Wang, Bo; Ward, Heather H.; Wandinger-Ness, Angela

    2015-01-01

    Analysis of perfusion-based bioreactors for organ engineering and a detailed evaluation of physical and biochemical parameters that measure dynamic changes within maturing cell-laden scaffolds are critical components of ex vivo tissue development that remain understudied topics in the tissue and organ engineering literature. Intricately designed bioreactors that house developing tissue are critical to properly recapitulate the in vivo environment, deliver nutrients within perfused media, and monitor physiological parameters of tissue development. Herein, we provide an in-depth description and analysis of two dual-purpose perfusion bioreactors that improve upon current bioreactor designs and enable comparative analyses of ex vivo scaffold recellularization strategies and cell growth performance during long-term maintenance culture of engineered kidney or liver tissues. Both bioreactors are effective at maximizing cell seeding of small-animal organ scaffolds and maintaining cell survival in extended culture. We further demonstrate noninvasive monitoring capabilities for tracking dynamic changes within scaffolds as the native cellular component is removed during decellularization and model human cells are introduced into the scaffold during recellularization and proliferate in maintenance culture. We found that hydrodynamic pressure drop (ΔP) across the retained scaffold vasculature is a noninvasive measurement of scaffold integrity. We further show that ΔP, and thus resistance to fluid flow through the scaffold, decreases with cell loss during decellularization and correspondingly increases to near normal values for whole organs following recellularization of the kidney or liver scaffolds. Perfused media may be further sampled in real time to measure soluble biomarkers (e.g., resazurin, albumin, or kidney injury molecule-1) that indicate degree of cellular metabolic activity, synthetic function, or engraftment into the scaffold. Cell growth within bioreactors is

  4. Dual-Purpose Bioreactors to Monitor Noninvasive Physical and Biochemical Markers of Kidney and Liver Scaffold Recellularization.

    PubMed

    Uzarski, Joseph S; Bijonowski, Brent M; Wang, Bo; Ward, Heather H; Wandinger-Ness, Angela; Miller, William M; Wertheim, Jason A

    2015-10-01

    Analysis of perfusion-based bioreactors for organ engineering and a detailed evaluation of physical and biochemical parameters that measure dynamic changes within maturing cell-laden scaffolds are critical components of ex vivo tissue development that remain understudied topics in the tissue and organ engineering literature. Intricately designed bioreactors that house developing tissue are critical to properly recapitulate the in vivo environment, deliver nutrients within perfused media, and monitor physiological parameters of tissue development. Herein, we provide an in-depth description and analysis of two dual-purpose perfusion bioreactors that improve upon current bioreactor designs and enable comparative analyses of ex vivo scaffold recellularization strategies and cell growth performance during long-term maintenance culture of engineered kidney or liver tissues. Both bioreactors are effective at maximizing cell seeding of small-animal organ scaffolds and maintaining cell survival in extended culture. We further demonstrate noninvasive monitoring capabilities for tracking dynamic changes within scaffolds as the native cellular component is removed during decellularization and model human cells are introduced into the scaffold during recellularization and proliferate in maintenance culture. We found that hydrodynamic pressure drop (ΔP) across the retained scaffold vasculature is a noninvasive measurement of scaffold integrity. We further show that ΔP, and thus resistance to fluid flow through the scaffold, decreases with cell loss during decellularization and correspondingly increases to near normal values for whole organs following recellularization of the kidney or liver scaffolds. Perfused media may be further sampled in real time to measure soluble biomarkers (e.g., resazurin, albumin, or kidney injury molecule-1) that indicate degree of cellular metabolic activity, synthetic function, or engraftment into the scaffold. Cell growth within bioreactors is

  5. Glucagon-Like Peptide-1 Excites Firing and Increases GABAergic Miniature Postsynaptic Currents (mPSCs) in Gonadotropin-Releasing Hormone (GnRH) Neurons of the Male Mice via Activation of Nitric Oxide (NO) and Suppression of Endocannabinoid Signaling Pathways

    PubMed Central

    Farkas, Imre; Vastagh, Csaba; Farkas, Erzsébet; Bálint, Flóra; Skrapits, Katalin; Hrabovszky, Erik; Fekete, Csaba; Liposits, Zsolt

    2016-01-01

    Glucagon-like peptide-1 (GLP-1), a metabolic signal molecule, regulates reproduction, although, the involved molecular mechanisms have not been elucidated, yet. Therefore, responsiveness of gonadotropin-releasing hormone (GnRH) neurons to the GLP-1 analog Exendin-4 and elucidation of molecular pathways acting downstream to the GLP-1 receptor (GLP-1R) have been challenged. Loose patch-clamp recordings revealed that Exendin-4 (100 nM–5 μM) elevated firing rate in hypothalamic GnRH-GFP neurons of male mice via activation of GLP-1R. Whole-cell patch-clamp measurements demonstrated increased excitatory GABAergic miniature postsynaptic currents (mPSCs) frequency after Exendin-4 administration, which was eliminated by the GLP-1R antagonist Exendin-3(9–39) (1 μM). Intracellular application of the G-protein inhibitor GDP-β-S (2 mM) impeded action of Exendin-4 on mPSCs, suggesting direct excitatory action of GLP-1 on GnRH neurons. Blockade of nitric-oxide (NO) synthesis by Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME; 100 μM) or N5-[Imino(propylamino)methyl]-L-ornithine hydrochloride (NPLA; 1 μM) or intracellular scavenging of NO by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (CPTIO; 1 mM) partially attenuated the excitatory effect of Exendin-4. Similar partial inhibition was achieved by hindering endocannabinoid pathway using cannabinoid receptor type-1 (CB1) inverse-agonist 1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-(1-piperidyl) pyrazole-3-carboxamide (AM251; 1 μM). Simultaneous blockade of NO and endocannabinoid signaling mechanisms eliminated action of Exendin-4 suggesting involvement of both retrograde machineries. Intracellular application of the transient receptor potential vanilloid 1 (TRPV1)-antagonist 2E-N-(2, 3-Dihydro-1,4-benzodioxin-6-yl)-3-[4-(1, 1-dimethylethyl)phenyl]-2-Propenamide (AMG9810; 10 μM) or the fatty acid amide hydrolase (FAAH)-inhibitor PF3845 (5 μM) impeded the GLP-1-triggered endocannabinoid

  6. Glucagon-Like Peptide-1 Excites Firing and Increases GABAergic Miniature Postsynaptic Currents (mPSCs) in Gonadotropin-Releasing Hormone (GnRH) Neurons of the Male Mice via Activation of Nitric Oxide (NO) and Suppression of Endocannabinoid Signaling Pathways.

    PubMed

    Farkas, Imre; Vastagh, Csaba; Farkas, Erzsébet; Bálint, Flóra; Skrapits, Katalin; Hrabovszky, Erik; Fekete, Csaba; Liposits, Zsolt

    2016-01-01

    Glucagon-like peptide-1 (GLP-1), a metabolic signal molecule, regulates reproduction, although, the involved molecular mechanisms have not been elucidated, yet. Therefore, responsiveness of gonadotropin-releasing hormone (GnRH) neurons to the GLP-1 analog Exendin-4 and elucidation of molecular pathways acting downstream to the GLP-1 receptor (GLP-1R) have been challenged. Loose patch-clamp recordings revealed that Exendin-4 (100 nM-5 μM) elevated firing rate in hypothalamic GnRH-GFP neurons of male mice via activation of GLP-1R. Whole-cell patch-clamp measurements demonstrated increased excitatory GABAergic miniature postsynaptic currents (mPSCs) frequency after Exendin-4 administration, which was eliminated by the GLP-1R antagonist Exendin-3(9-39) (1 μM). Intracellular application of the G-protein inhibitor GDP-β-S (2 mM) impeded action of Exendin-4 on mPSCs, suggesting direct excitatory action of GLP-1 on GnRH neurons. Blockade of nitric-oxide (NO) synthesis by Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME; 100 μM) or N(5)-[Imino(propylamino)methyl]-L-ornithine hydrochloride (NPLA; 1 μM) or intracellular scavenging of NO by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (CPTIO; 1 mM) partially attenuated the excitatory effect of Exendin-4. Similar partial inhibition was achieved by hindering endocannabinoid pathway using cannabinoid receptor type-1 (CB1) inverse-agonist 1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-(1-piperidyl) pyrazole-3-carboxamide (AM251; 1 μM). Simultaneous blockade of NO and endocannabinoid signaling mechanisms eliminated action of Exendin-4 suggesting involvement of both retrograde machineries. Intracellular application of the transient receptor potential vanilloid 1 (TRPV1)-antagonist 2E-N-(2, 3-Dihydro-1,4-benzodioxin-6-yl)-3-[4-(1, 1-dimethylethyl)phenyl]-2-Propenamide (AMG9810; 10 μM) or the fatty acid amide hydrolase (FAAH)-inhibitor PF3845 (5 μM) impeded the GLP-1-triggered endocannabinoid

  7. Glucagon-Like Peptide-1 Excites Firing and Increases GABAergic Miniature Postsynaptic Currents (mPSCs) in Gonadotropin-Releasing Hormone (GnRH) Neurons of the Male Mice via Activation of Nitric Oxide (NO) and Suppression of Endocannabinoid Signaling Pathways.

    PubMed

    Farkas, Imre; Vastagh, Csaba; Farkas, Erzsébet; Bálint, Flóra; Skrapits, Katalin; Hrabovszky, Erik; Fekete, Csaba; Liposits, Zsolt

    2016-01-01

    Glucagon-like peptide-1 (GLP-1), a metabolic signal molecule, regulates reproduction, although, the involved molecular mechanisms have not been elucidated, yet. Therefore, responsiveness of gonadotropin-releasing hormone (GnRH) neurons to the GLP-1 analog Exendin-4 and elucidation of molecular pathways acting downstream to the GLP-1 receptor (GLP-1R) have been challenged. Loose patch-clamp recordings revealed that Exendin-4 (100 nM-5 μM) elevated firing rate in hypothalamic GnRH-GFP neurons of male mice via activation of GLP-1R. Whole-cell patch-clamp measurements demonstrated increased excitatory GABAergic miniature postsynaptic currents (mPSCs) frequency after Exendin-4 administration, which was eliminated by the GLP-1R antagonist Exendin-3(9-39) (1 μM). Intracellular application of the G-protein inhibitor GDP-β-S (2 mM) impeded action of Exendin-4 on mPSCs, suggesting direct excitatory action of GLP-1 on GnRH neurons. Blockade of nitric-oxide (NO) synthesis by Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME; 100 μM) or N(5)-[Imino(propylamino)methyl]-L-ornithine hydrochloride (NPLA; 1 μM) or intracellular scavenging of NO by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (CPTIO; 1 mM) partially attenuated the excitatory effect of Exendin-4. Similar partial inhibition was achieved by hindering endocannabinoid pathway using cannabinoid receptor type-1 (CB1) inverse-agonist 1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-(1-piperidyl) pyrazole-3-carboxamide (AM251; 1 μM). Simultaneous blockade of NO and endocannabinoid signaling mechanisms eliminated action of Exendin-4 suggesting involvement of both retrograde machineries. Intracellular application of the transient receptor potential vanilloid 1 (TRPV1)-antagonist 2E-N-(2, 3-Dihydro-1,4-benzodioxin-6-yl)-3-[4-(1, 1-dimethylethyl)phenyl]-2-Propenamide (AMG9810; 10 μM) or the fatty acid amide hydrolase (FAAH)-inhibitor PF3845 (5 μM) impeded the GLP-1-triggered endocannabinoid

  8. Glucagon-Like Peptide-1 Excites Firing and Increases GABAergic Miniature Postsynaptic Currents (mPSCs) in Gonadotropin-Releasing Hormone (GnRH) Neurons of the Male Mice via Activation of Nitric Oxide (NO) and Suppression of Endocannabinoid Signaling Pathways

    PubMed Central

    Farkas, Imre; Vastagh, Csaba; Farkas, Erzsébet; Bálint, Flóra; Skrapits, Katalin; Hrabovszky, Erik; Fekete, Csaba; Liposits, Zsolt

    2016-01-01

    Glucagon-like peptide-1 (GLP-1), a metabolic signal molecule, regulates reproduction, although, the involved molecular mechanisms have not been elucidated, yet. Therefore, responsiveness of gonadotropin-releasing hormone (GnRH) neurons to the GLP-1 analog Exendin-4 and elucidation of molecular pathways acting downstream to the GLP-1 receptor (GLP-1R) have been challenged. Loose patch-clamp recordings revealed that Exendin-4 (100 nM–5 μM) elevated firing rate in hypothalamic GnRH-GFP neurons of male mice via activation of GLP-1R. Whole-cell patch-clamp measurements demonstrated increased excitatory GABAergic miniature postsynaptic currents (mPSCs) frequency after Exendin-4 administration, which was eliminated by the GLP-1R antagonist Exendin-3(9–39) (1 μM). Intracellular application of the G-protein inhibitor GDP-β-S (2 mM) impeded action of Exendin-4 on mPSCs, suggesting direct excitatory action of GLP-1 on GnRH neurons. Blockade of nitric-oxide (NO) synthesis by Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME; 100 μM) or N5-[Imino(propylamino)methyl]-L-ornithine hydrochloride (NPLA; 1 μM) or intracellular scavenging of NO by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (CPTIO; 1 mM) partially attenuated the excitatory effect of Exendin-4. Similar partial inhibition was achieved by hindering endocannabinoid pathway using cannabinoid receptor type-1 (CB1) inverse-agonist 1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-(1-piperidyl) pyrazole-3-carboxamide (AM251; 1 μM). Simultaneous blockade of NO and endocannabinoid signaling mechanisms eliminated action of Exendin-4 suggesting involvement of both retrograde machineries. Intracellular application of the transient receptor potential vanilloid 1 (TRPV1)-antagonist 2E-N-(2, 3-Dihydro-1,4-benzodioxin-6-yl)-3-[4-(1, 1-dimethylethyl)phenyl]-2-Propenamide (AMG9810; 10 μM) or the fatty acid amide hydrolase (FAAH)-inhibitor PF3845 (5 μM) impeded the GLP-1-triggered endocannabinoid

  9. Miniature open channel scrubbers for gas collection.

    PubMed

    Toda, Kei; Koga, Tomoko; Tanaka, Toshinori; Ohira, Shin-Ichi; Berg, Jordan M; Dasgupta, Purnendu K

    2010-10-15

    An open channel scrubber is proposed as a miniature fieldable gas collector. The device is 100mm in length, 26 mm in width and 22 mm in thickness. The channel bottom is rendered hydrophilic and liquid flows as a thin layer on the bottom. Air sample flows atop the appropriately chosen flowing liquid film and analyte molecules are absorbed into the liquid. There is no membrane at the air-liquid interface: they contact directly each other. Analyte species collected over a 10 min interval are determined by fluorometric flow analysis or ion chromatography. A calculation algorithm was developed to estimate the collection efficiency a priori; experimental and simulated results agreed well. The characteristics of the open channel scrubber are discussed in this paper from both theoretical and experimental points of view. In addition to superior collection efficiencies at relatively high sample air flow rates, this geometry is particularly attractive that there is no change in collection performance due to membrane fouling. We demonstrate field use for analysis of ambient SO(2) near an active volcano. This is basic investigation of membraneless miniature scrubber and is expected to lead development of an excellent micro-gas analysis system integrated with a detector for continuous measurements.

  10. Miniaturized integration of a fluorescence microscope

    PubMed Central

    Ghosh, Kunal K.; Burns, Laurie D.; Cocker, Eric D.; Nimmerjahn, Axel; Ziv, Yaniv; Gamal, Abbas El; Schnitzer, Mark J.

    2013-01-01

    The light microscope is traditionally an instrument of substantial size and expense. Its miniaturized integration would enable many new applications based on mass-producible, tiny microscopes. Key prospective usages include brain imaging in behaving animals towards relating cellular dynamics to animal behavior. Here we introduce a miniature (1.9 g) integrated fluorescence microscope made from mass-producible parts, including semiconductor light source and sensor. This device enables high-speed cellular-level imaging across ∼0.5 mm2 areas in active mice. This capability allowed concurrent tracking of Ca2+ spiking in >200 Purkinje neurons across nine cerebellar microzones. During mouse locomotion, individual microzones exhibited large-scale, synchronized Ca2+ spiking. This is a mesoscopic neural dynamic missed by prior techniques for studying the brain at other length scales. Overall, the integrated microscope is a potentially transformative technology that permits distribution to many animals and enables diverse usages, such as portable diagnostics or microscope arrays for large-scale screens. PMID:21909102

  11. Miniature open channel scrubbers for gas collection.

    PubMed

    Toda, Kei; Koga, Tomoko; Tanaka, Toshinori; Ohira, Shin-Ichi; Berg, Jordan M; Dasgupta, Purnendu K

    2010-10-15

    An open channel scrubber is proposed as a miniature fieldable gas collector. The device is 100mm in length, 26 mm in width and 22 mm in thickness. The channel bottom is rendered hydrophilic and liquid flows as a thin layer on the bottom. Air sample flows atop the appropriately chosen flowing liquid film and analyte molecules are absorbed into the liquid. There is no membrane at the air-liquid interface: they contact directly each other. Analyte species collected over a 10 min interval are determined by fluorometric flow analysis or ion chromatography. A calculation algorithm was developed to estimate the collection efficiency a priori; experimental and simulated results agreed well. The characteristics of the open channel scrubber are discussed in this paper from both theoretical and experimental points of view. In addition to superior collection efficiencies at relatively high sample air flow rates, this geometry is particularly attractive that there is no change in collection performance due to membrane fouling. We demonstrate field use for analysis of ambient SO(2) near an active volcano. This is basic investigation of membraneless miniature scrubber and is expected to lead development of an excellent micro-gas analysis system integrated with a detector for continuous measurements. PMID:20875590

  12. Maximizing strain in miniaturized dielectric elastomer actuators

    NASA Astrophysics Data System (ADS)

    Rosset, Samuel; Araromi, Oluwaseun; Shea, Herbert

    2015-04-01

    We present a theoretical model to optimise the unidirectional motion of a rigid object bonded to a miniaturized dielectric elastomer actuator (DEA), a configuration found for example in AMI's haptic feedback devices, or in our tuneable RF phase shifter. Recent work has shown that unidirectional motion is maximized when the membrane is both anistropically prestretched and subjected to a dead load in the direction of actuation. However, the use of dead weights for miniaturized devices is clearly highly impractical. Consequently smaller devices use the membrane itself to generate the opposing force. Since the membrane covers the entire frame, one has the same prestretch condition in the active (actuated) and passive zones. Because the passive zone contracts when the active zone expands, it does not provide a constant restoring force, reducing the maximum achievable actuation strain. We have determined the optimal ratio between the size of the electrode (active zone) and the passive zone, as well as the optimal prestretch in both in-plane directions, in order to maximize the absolute displacement of the rigid object placed at the active/passive border. Our model and experiments show that the ideal active ratio is 50%, with a displacement twice smaller than what can be obtained with a dead load. We expand our fabrication process to also show how DEAs can be laser-post-processed to remove carefully chosen regions of the passive elastomer membrane, thereby increasing the actuation strain of the device.

  13. Miniature Oxidizer Ionizer for a Fuel Cell

    NASA Technical Reports Server (NTRS)

    Hartley, Frank

    2006-01-01

    A proposed miniature device for ionizing the oxygen (or other oxidizing gas) in a fuel cell would consist mostly of a membrane ionizer using the same principles as those of the device described in the earlier article, Miniature Bipolar Electrostatic Ion Thruster (NPO-21057). The oxidizing gas would be completely ionized upon passage through the holes in the membrane ionizer. The resulting positively charged atoms or molecules of oxidizing gas could then, under the influence of the fringe fields of the ionizer, move toward the fuel-cell cathode that would be part of a membrane/electrode assembly comprising the cathode, a solid-electrolyte membrane, and an anode. The electro-oxidized state of the oxidizer atoms and molecules would enhance transfer of them through the cathode, thereby reducing the partial pressure of the oxidizer gas between the ionizer and the fuel-cell cathode, thereby, in turn, causing further inflow of oxidizer gas through the holes in the membrane ionizer. Optionally the ionizer could be maintained at a positive electric potential with respect to the cathode, in which case the resulting electric field would accelerate the ions toward the cathode.

  14. Miniature Optical Wide-Angle-Lens Startracker (Mini-OWLS)

    NASA Astrophysics Data System (ADS)

    Miller, Rick; Coulter, Joe E.; Levine, Seymour

    1993-02-01

    This paper provides a brief overview of the design considerations and the current status of the Miniature Optical Wide-Angle Lens Startracker Program. Mini-OWLS offers a revolutionary alternative to the conventional startracker. It is a small, lightweight, low cost, high performance startracker that can be used in a variety of applications including calibration and alignment of Inertial Measurement Units (IMU's) Mini-OWLS makes use of a strap down design incorporating Holographic Optical Elements (HOES) in place of conventional optics. HOES can be multiplexed so that the same aperture can be used for multiple separate optical paths looking in several directions simultaneously without startracker rotation. Additionally, separate Schmidt corrector plates are not required to compensate for spherical aberration. The optical assembly, or what would normally be considered as the telescope, is less than 20 cc in volume, weighs less than 55 grams, and contains the equivalent of three individual telescopes. Each one has a 4 deg Field of View (FOV) with a field of regard of 48 square degrees. Mini-OWLS has a bandwidth of approximately 300 nm in or near the visible wavelength. The projected resolution of the startracker is 5 to 10 arcseconds, depending on the centroiding algorithm used. The Mini-OWLS program was initiated last year and represents a miniaturized version of a similar design for aeronautical applications. The contract is managed by Wright Laboratory, Air Force Systems Command, Wright-Patterson AFB, Ohio, with funding from the Strategic Defense Initiative Organization through Eglin AFB. The initial phase of the program is to build and test a development unit. The second phase is to integrate the startracker with the Charles Stark Draper Laboratory Micromechanical Inertial Guidance System (MIGS) and the Signal Processing Packaging Design (SPPD) being developed by Texas Instruments. The preliminary design review was conducted in November 1991. Three-axes prototype

  15. Miniature Optical Wide-Angle-Lens Startracker (Mini-OWLS)

    NASA Technical Reports Server (NTRS)

    Miller, Rick; Coulter, Joe E.; Levine, Seymour

    1993-01-01

    This paper provides a brief overview of the design considerations and the current status of the Miniature Optical Wide-Angle Lens Startracker Program. Mini-OWLS offers a revolutionary alternative to the conventional startracker. It is a small, lightweight, low cost, high performance startracker that can be used in a variety of applications including calibration and alignment of Inertial Measurement Units (IMU's) Mini-OWLS makes use of a strap down design incorporating Holographic Optical Elements (HOES) in place of conventional optics. HOES can be multiplexed so that the same aperture can be used for multiple separate optical paths looking in several directions simultaneously without startracker rotation. Additionally, separate Schmidt corrector plates are not required to compensate for spherical aberration. The optical assembly, or what would normally be considered as the telescope, is less than 20 cc in volume, weighs less than 55 grams, and contains the equivalent of three individual telescopes. Each one has a 4 deg Field of View (FOV) with a field of regard of 48 square degrees. Mini-OWLS has a bandwidth of approximately 300 nm in or near the visible wavelength. The projected resolution of the startracker is 5 to 10 arcseconds, depending on the centroiding algorithm used. The Mini-OWLS program was initiated last year and represents a miniaturized version of a similar design for aeronautical applications. The contract is managed by Wright Laboratory, Air Force Systems Command, Wright-Patterson AFB, Ohio, with funding from the Strategic Defense Initiative Organization through Eglin AFB. The initial phase of the program is to build and test a development unit. The second phase is to integrate the startracker with the Charles Stark Draper Laboratory Micromechanical Inertial Guidance System (MIGS) and the Signal Processing Packaging Design (SPPD) being developed by Texas Instruments. The preliminary design review was conducted in November 1991. Three-axes prototype

  16. Magnet-Based System for Docking of Miniature Spacecraft

    NASA Technical Reports Server (NTRS)

    Howard, Nathan; Nguyen, Hai D.

    2007-01-01

    A prototype system for docking a miniature spacecraft with a larger spacecraft has been developed by engineers at the Johnson Space Center. Engineers working on Mini AERCam, a free-flying robotic camera, needed to find a way to successfully dock and undock their miniature spacecraft to refuel the propulsion and recharge the batteries. The subsystems developed (see figure) include (1) a docking port, designed for the larger spacecraft, which contains an electromagnet, a ball lock mechanism, and a service probe; and (2) a docking cluster, designed for the smaller spacecraft, which contains either a permanent magnet or an electromagnet. A typical docking operation begins with the docking spacecraft maneuvering into position near the docking port on the parent vehicle. The electromagnet( s) are then turned on, and, if necessary, the docking spacecraft is then maneuvered within the capture envelope of the docking port. The capture envelope for this system is approximated by a 5-in. (12.7-cm) cube centered on the front of the docking-port electromagnet and within an angular misalignment of <30 . Thereafter, the magnetic forces draw the smaller spacecraft toward the larger one and this brings the spacecraft into approximate alignment prior to contact. Mechanical alignment guides provide the final rotational alignment into one of 12 positions. Once the docking vehicle has been captured magnetically in the docking port, the ball-lock mechanism is activated, which locks the two spacecraft together. At this point the electromagnet( s) are turned off, and the service probe extended if recharge and refueling are to be performed. Additionally, during undocking, the polarity of one electromagnet can be reversed to provide a gentle push to separate the two spacecraft. This system is currently being incorporated into the design of Mini AERCam vehicle.

  17. Miniaturized Environmental Scanning Electron Microscope for In Situ Planetary Studies

    NASA Technical Reports Server (NTRS)

    Gaskin, Jessica; Abbott, Terry; Medley, Stephanie; Gregory, Don; Thaisen, Kevin; Taylor , Lawrence; Ramsey, Brian; Jerman, Gregory; Sampson, Allen; Harvey, Ralph

    2010-01-01

    The exploration of remote planetary surfaces calls for the advancement of low power, highly-miniaturized instrumentation. Instruments of this nature that are capable of multiple types of analyses will prove to be particularly useful as we prepare for human return to the moon, and as we continue to explore increasingly remote locations in our Solar System. To this end, our group has been developing a miniaturized Environmental-Scanning Electron Microscope (mESEM) capable of remote investigations of mineralogical samples through in-situ topographical and chemical analysis on a fine scale. The functioning of an SEM is well known: an electron beam is focused to nanometer-scale onto a given sample where resulting emissions such as backscattered and secondary electrons, X-rays, and visible light are registered. Raster scanning the primary electron beam across the sample then gives a fine-scale image of the surface topography (texture), crystalline structure and orientation, with accompanying elemental composition. The flexibility in the types of measurements the mESEM is capable of, makes it ideally suited for a variety of applications. The mESEM is appropriate for use on multiple planetary surfaces, and for a variety of mission goals (from science to non-destructive analysis to ISRU). We will identify potential applications and range of potential uses related to planetary exploration. Over the past few of years we have initiated fabrication and testing of a proof-of-concept assembly, consisting of a cold-field-emission electron gun and custom high-voltage power supply, electrostatic electron-beam focusing column, and scanning-imaging electronics plus backscatter detector. Current project status will be discussed. This effort is funded through the NASA Research Opportunities in Space and Earth Sciences - Planetary Instrument Definition and Development Program.

  18. Disposable polymeric cryogel bioreactor matrix for therapeutic protein production.

    PubMed

    Jain, Era; Kumar, Ashok

    2013-05-01

    Low cost and high efficiency make disposable bioreactors feasible for small-scale therapeutic development and initial clinical trials. We have developed a cryogel-based disposable bioreactor matrix, which has been used for production of protein therapeutics such as urokinase and monoclonal antibodies (mAbs). The protocol discusses the application of a cryogel bioreactor for mAb production. Cryogels composed of either polyacrylamide (PAAm) coupled to gelatin or semi-interpenetrating PAAm-chitosan are synthesized by free-radical polymerization at -12 °C. Hybridoma cells are immobilized over the cryogel bioreactor and incubated for 48 h. Medium is circulated thereafter at 0.2 ml min(-1) and bioreactors can be run continuously for 60 d. The cryogel-based packed-bed bioreactor can be formulated as a monolith or as beads; it also has an efficiency four times what can be obtained using a tissue-culture flask, a high surface-to-volume ratio and effective nutrient transport. After incubation, the bioreactor setup will take about 60 min using a pre-prepared sterilized cryogel.

  19. Enhanced membrane bioreactor process without chemical cleaning.

    PubMed

    Krause, S; Zimmermann, B; Meyer-Blumenroth, U; Lamparter, W; Siembida, B; Cornel, P

    2010-01-01

    In membrane bioreactors (MBR) for wastewater treatment, the separation of activated sludge and treated water takes place by membrane filtration. Due to the small footprint and superior effluent quality, the number of membrane bioreactors used in wastewater treatment is rapidly increasing. A major challenge in this process is the fouling of the membranes which results in permeability decrease and the demand of chemical cleaning procedures. With the objective of a chemical-free process, the removal of the fouling layer by continuous physical abrasion was investigated. Therefore, particles (granules) were added to the activated sludge in order to realise a continuous abrasion of the fouling layer. During operation for more than 8 months, the membranes showed no decrease in permeability. Fluxes up to 40 L/(m(2) h) were achieved. An online turbidity measurement was installed for the effluent control and showed no change during this test period. For comparison, a reference (standard MBR process without granules) was operated which demonstrated permeability loss at lower fluxes and required chemical cleaning. Altogether with this process an operation at higher fluxes and no use of cleaning chemicals will increase the cost efficiency of the MBR-process.

  20. Engineering Parameters in Bioreactor's Design: A Critical Aspect in Tissue Engineering

    PubMed Central

    Amoabediny, Ghassem; Pouran, Behdad; Tabesh, Hadi; Shokrgozar, Mohammad Ali; Haghighipour, Nooshin; Khatibi, Nahid; Mottaghy, Khosrow; Zandieh-Doulabi, Behrouz

    2013-01-01

    Bioreactors are important inevitable part of any tissue engineering (TE) strategy as they aid the construction of three-dimensional functional tissues. Since the ultimate aim of a bioreactor is to create a biological product, the engineering parameters, for example, internal and external mass transfer, fluid velocity, shear stress, electrical current distribution, and so forth, are worth to be thoroughly investigated. The effects of such engineering parameters on biological cultures have been addressed in only a few preceding studies. Furthermore, it would be highly inefficient to determine the optimal engineering parameters by trial and error method. A solution is provided by emerging modeling and computational tools and by analyzing oxygen, carbon dioxide, and nutrient and metabolism waste material transports, which can simulate and predict the experimental results. Discovering the optimal engineering parameters is crucial not only to reduce the cost and time of experiments, but also to enhance efficacy and functionality of the tissue construct. This review intends to provide an inclusive package of the engineering parameters together with their calculation procedure in addition to the modeling techniques in TE bioreactors. PMID:24000327

  1. A Pulsatile Bioreactor for Conditioning of Tissue-Engineered Cardiovascular Constructs under Endoscopic Visualization

    PubMed Central

    König, Fabian; Hollweck, Trixi; Pfeifer, Stefan; Reichart, Bruno; Wintermantel, Erich; Hagl, Christian; Akra, Bassil

    2012-01-01

    Heart valve disease (HVD) is a globally increasing problem and accounts for thousands of deaths yearly. Currently end-stage HVD can only be treated by total valve replacement, however with major drawbacks. To overcome the limitations of conventional substitutes, a new clinical approach based on cell colonization of artificially manufactured heart valves has been developed. Even though this attempt seems promising, a confluent and stable cell layer has not yet been achieved due to the high stresses present in this area of the human heart. This study describes a bioreactor with a new approach to cell conditioning of tissue engineered heart valves. The bioreactor provides a low pulsatile flow that grants the correct opening and closing of the valve without high shear stresses. The flow rate can be regulated allowing a steady and sensitive conditioning process. Furthermore, the correct functioning of the valve can be monitored by endoscope surveillance in real-time. The tubeless and modular design allows an accurate, simple and faultless assembly of the reactor in a laminar flow chamber. It can be concluded that the bioreactor provides a strong tool for dynamic pre-conditioning and monitoring of colonized heart valve prostheses physiologically exposed to shear stress. PMID:24955628

  2. A Pulsatile Bioreactor for Conditioning of Tissue-Engineered Cardiovascular Constructs under Endoscopic Visualization.

    PubMed

    König, Fabian; Hollweck, Trixi; Pfeifer, Stefan; Reichart, Bruno; Wintermantel, Erich; Hagl, Christian; Akra, Bassil

    2012-07-19

    Heart valve disease (HVD) is a globally increasing problem and accounts for thousands of deaths yearly. Currently end-stage HVD can only be treated by total valve replacement, however with major drawbacks. To overcome the limitations of conventional substitutes, a new clinical approach based on cell colonization of artificially manufactured heart valves has been developed. Even though this attempt seems promising, a confluent and stable cell layer has not yet been achieved due to the high stresses present in this area of the human heart. This study describes a bioreactor with a new approach to cell conditioning of tissue engineered heart valves. The bioreactor provides a low pulsatile flow that grants the correct opening and closing of the valve without high shear stresses. The flow rate can be regulated allowing a steady and sensitive conditioning process. Furthermore, the correct functioning of the valve can be monitored by endoscope surveillance in real-time. The tubeless and modular design allows an accurate, simple and faultless assembly of the reactor in a laminar flow chamber. It can be concluded that the bioreactor provides a strong tool for dynamic pre-conditioning and monitoring of colonized heart valve prostheses physiologically exposed to shear stress.

  3. Biological technologies for the removal of sulfur containing compounds from waste streams: bioreactors and microbial characteristics.

    PubMed

    Li, Lin; Zhang, Jingying; Lin, Jian; Liu, Junxin

    2015-10-01

    Waste gases containing sulfur compounds, such as hydrogen sulfide, sulfur dioxide, thioethers, and mercaptan, produced and emitted from industrial processes, wastewater treatment, and landfill waste may cause undesirable issues in adjacent areas and contribute to atmospheric pollution. Their control has been an area of concern and research for many years. As alternative to conventional physicochemical air pollution control technologies, biological treatment processes which can transform sulfur compounds to harmless products by microbial activity, have gained in popularity due to their efficiency, cost-effectiveness and environmental acceptability. This paper provides an overview of the current biological techniques used for the treatment of air streams contaminated with sulfur compounds as well as the advances made in the past year. The discussion focuses on bioreactor configuration and design, mechanism of operation, insights into the overall biological treatment process, and the characterization of the microbial species present in bioreactors, their populations and their interactions with the environment. Some bioreactor case studies are also introduced. Finally, the perspectives on future research and development needs in this research area were also highlighted.

  4. Achieving "Final Storage Quality" of municipal solid waste in pilot scale bioreactor landfills.

    PubMed

    Valencia, R; van der Zon, W; Woelders, H; Lubberding, H J; Gijzen, H J

    2009-01-01

    Entombed waste in current sanitary landfills will generate biogas and leachate when physical barriers fail in the future, allowing the intrusion of moisture into the waste mass contradicting the precepts of the sustainability concept. Bioreactor landfills are suggested as a sustainable option to achieve Final Storage Quality (FSQ) status of waste residues; however, it is not clear what characteristics the residues should have in order to stop operation and after-care monitoring schemes. An experiment was conducted to determine the feasibility to achieve FSQ status (Waste Acceptance Criteria of the European Landfill Directive) of residues in a pilot scale bioreactor landfill. The results of the leaching test were very encouraging due to their proximity to achieve the proposed stringent FSQ criterion after 2 years of operation. Furthermore, residues have the same characteristics of alternative waste stabilisation parameters (low BMP, BOD/COD ratio, VS content, SO4(2-)/Cl- ratio) established by other researchers. Mass balances showed that the bioreactor landfill simulator was capable of practically achieving biological stabilisation after 2 years of operation, while releasing approximately 45% of the total available (organic and inorganic) carbon and nitrogen into the liquid and gas phases.

  5. Spaceflight bioreactor studies of cells and tissues.

    PubMed

    Freed, Lisa E; Vunjak-Novakovic, Gordana

    2002-01-01

    Studies of the fundamental role of gravity in the development and function of biological organisms are a central component of the human exploration of space. Microgravity affects numerous physical phenomena relevant to biological research, including the hydrostatic pressure in fluid filled vesicles, sedimentation of organelles, and buoyancy-driven convection of flow and heat. These physical phenomena can in turn directly and indirectly affect cellular morphology, metabolism, locomotion, secretion of extracellular matrix and soluble signals, and assembly into functional tissues. Studies aimed at distinguishing specific effects of gravity on biological systems require the ability to: (i) control and systematically vary gravity, e.g. by utilizing the microgravity environment of space in conjunction with an in-flight centrifuge; and (ii) maintain constant all other factors in the immediate environment, including in particular concentrations and exchange rates of biochemical species and hydrodynamic shear. The latter criteria imply the need for gravity-independent mechanisms to provide for mass transport between the cells and their environment. Available flight hardware has largely determined the experimental design and scientific objectives of spaceflight cell and tissue culture studies carried out to date. Simple culture vessels have yielded important quantitative data, and helped establish in vitro models of cell locomotion, growth and differentiation in various mammalian cell types including embryonic lung cells [6], lymphocytes [2,8], and renal cells [7,31]. Studies done using bacterial cells established the first correlations between gravity-dependent factors such as cell settling velocity and diffusional distance and the respective cell responses [12]. The development of advanced bioreactors for microgravity cell and tissue culture and for tissue engineering has benefited both research areas and provided relevant in vitro model systems for studies of astronaut

  6. Design and evaluation of a bioreactor with application to forensic burial environments.

    PubMed

    Dunphy, Melissa A; Weisensee, Katherine E; Mikhailova, Elena A; Harman, Melinda K

    2015-12-01

    Existing forensic taphonomic methods lack specificity in estimating the postmortem interval (PMI) in the period following active decomposition. New methods, such as the use of citrate concentration in bone, are currently being considered; however, determining the applicability of these methods in differing environmental contexts is challenging. This research aims to design a forensic bioreactor that can account for environmental factors known to impact decomposition, specifically temperature, moisture, physical damage from animals, burial depth, soil pH, and organic matter content. These forensically relevant environmental variables were characterized in a soil science context. The resulting metrics were soil temperature regime, soil moisture regime, slope, texture, soil horizon, cation exchange capacity, soil pH, and organic matter content. Bioreactor chambers were constructed using sterilized thin-walled polystyrene boxes housed in calibrated temperature units. Gravesoil was represented using mineral soil (Ultisols), and organic soil proxy for Histosols, horticulture mix. Gravesoil depth was determined using mineral soil horizons A and Bt2 to simulate surface scatter and shallow grave burial respectively. A total of fourteen different environmental conditions were created and controlled successfully over a 90-day experiment. These results demonstrate successful implementation and control of forensic bioreactor simulating precise environments in a single research location, rather than site-specific testing occurring in different geographic regions. Bone sections were grossly assessed for weathering characteristics, which revealed notable differences related to exposure to different temperature regimes and soil types. Over the short 90-day duration of this experiment, changes in weathering characteristics were more evident across the different temperature regimes rather than the soil types. Using this methodology, bioreactor systems can be created to replicate many

  7. Congenital urethral stenosis in a male miniature piglet

    PubMed Central

    Pouleur-Larrat, Bénédicte; Maccolini, Edouard; Carmel, Eric Norman; Hélie, Pierre

    2014-01-01

    A 2-month-old male miniature pig showed progressive abdominal pain, pollakiuria, and stranguria that progressed to complete urinary obstruction. Postmortem examination revealed idiopathic urethral stenosis at the level of the recess, of probable congenital origin. Urinary tract malformations should be included in the differential diagnosis of miniature piglets with urinary disorders. PMID:24891635

  8. The Miniature Job Training and Evaluation Approach: Additional Findings.

    ERIC Educational Resources Information Center

    Siegel, Arthur I.

    1983-01-01

    Describes miniature job training and evaluation situations administered to 1,034 "low aptitude" Navy recruits. Checklist criterion data describing the on-the-job performance of the sample were collected after the recruits were on their fleet assignments. The results confirmed the predictive validity of the miniature job training approach.…

  9. A miniaturized artificial mastoid using a skull simulator.

    PubMed

    Stenfelt, S P; Håkansson, B E

    1998-01-01

    A miniaturized artificial mastoid of size and weight that allow calibration and measurement of bone conduction hearing aids in a conventional audiometric soundproof box has been developed. Its level of mechanical impedance corresponds to the standard IEC 373 (1990) within the frequency range 250 Hz to 8 kHz. The miniaturized artificial mastoid consists of three parts: coupler, skull simulator (TU-1000), and an external electrical correction filter. The coupler is a highly damped mass-spring system designed to give the miniaturized artificial mastoid mechanical impedance in accordance with the standard IEC 373 (1990). It was found that the miniaturized artificial mastoid yielded results that are in correspondence with results obtained with the Brüel & Kjaer type 4930 artificial mastoid for frequencies above 450 Hz. Thus, at these frequencies, the miniaturized artificial mastoid can be used for audiometer calibration as well as measurement of bone conduction hearing aids.

  10. Development of an energy-saving anaerobic hybrid membrane bioreactors for 2-chlorophenol-contained wastewater treatment.

    PubMed

    Wang, Yun-Kun; Pan, Xin-Rong; Sheng, Guo-Ping; Li, Wen-Wei; Shi, Bing-Jing; Yu, Han-Qing

    2015-12-01

    A novel energy-saving anaerobic hybrid membrane bioreactor (AnHMBR) with mesh filter, which takes advantage of anaerobic membrane bioreactor and fixed-bed biofilm reactor, is developed for low-strength 2-chlorophenol (2-CP)-contained wastewater treatment. In this system, the anaerobic membrane bioreactor is stuffed with granular activated carbon to construct an anaerobic hybrid fixed-bed biofilm membrane bioreactor. The effluent turbidity from the AnHMBR system was low during most of the operation period, and the chemical oxygen demand and 2-CP removal efficiencies averaged 82.3% and 92.6%, respectively. Furthermore, a low membrane fouling rate was achieved during the operation. During the AnHMBR operation, the only energy consumption was for feed pump. And a low energy demand of 0.0045-0.0063kWhm(-3) was estimated under the current operation conditions. All these results demonstrated that this novel AnHMBR is a sustainable technology for treating 2-CP-contained wastewater.

  11. Bioreactors Drive Advances in Tissue Engineering

    NASA Technical Reports Server (NTRS)

    2012-01-01

    It was an unlikely moment for inspiration. Engineers David Wolf and Ray Schwarz stopped by their lab around midday. Wolf, of Johnson Space Center, and Schwarz, with NASA contractor Krug Life Sciences (now Wyle Laboratories Inc.), were part of a team tasked with developing a unique technology with the potential to enhance medical research. But that wasn t the focus at the moment: The pair was rounding up colleagues interested in grabbing some lunch. One of the lab s other Krug engineers, Tinh Trinh, was doing something that made Wolf forget about food. Trinh was toying with an electric drill. He had stuck the barrel of a syringe on the bit; it spun with a high-pitched whirr when he squeezed the drill s trigger. At the time, a multidisciplinary team of engineers and biologists including Wolf, Schwarz, Trinh, and project manager Charles D. Anderson, who formerly led the recovery of the Apollo capsules after splashdown and now worked for Krug was pursuing the development of a technology called a bioreactor, a cylindrical device used to culture human cells. The team s immediate goal was to grow human kidney cells to produce erythropoietin, a hormone that regulates red blood cell production and can be used to treat anemia. But there was a major barrier to the technology s success: Moving the liquid growth media to keep it from stagnating resulted in turbulent conditions that damaged the delicate cells, causing them to quickly die. The team was looking forward to testing the bioreactor in space, hoping the device would perform more effectively in microgravity. But on January 28, 1986, the Space Shuttle Challenger broke apart shortly after launch, killing its seven crewmembers. The subsequent grounding of the shuttle fleet had left researchers with no access to space, and thus no way to study the effects of microgravity on human cells. As Wolf looked from Trinh s syringe-capped drill to where the bioreactor sat on a workbench, he suddenly saw a possible solution to both

  12. Ammonia quantitative analysis model based on miniaturized Al ionization gas sensor and non-linear bistable dynamic model

    PubMed Central

    Ma, Rongfei

    2015-01-01

    In this paper, ammonia quantitative analysis based on miniaturized Al ionization gas sensor and non-linear bistable dynamic model was proposed. Al plate anodic gas-ionization sensor was used to obtain the current-voltage (I-V) data. Measurement data was processed by non-linear bistable dynamics model. Results showed that the proposed method quantitatively determined ammonia concentrations. PMID:25975362

  13. Miniature Neutron-Alpha Activation Spectrometer

    NASA Astrophysics Data System (ADS)

    Rhodes, Edgar; Holloway, James Paul; He, Zhong; Goldsten, John

    2002-10-01

    We are developing a miniature neutron-alpha activation spectrometer for in-situ analysis of chem-bio samples, including rocks, fines, ices, and drill cores, suitable for a lander or Rover platform for Mars or outer-planet missions. In the neutron-activation mode, penetrating analysis will be performed of the whole sample using a γ spectrometer and in the α-activation mode, the sample surface will be analyzed using Rutherford-backscatter and x-ray spectrometers. Novel in our approach is the development of a switchable radioactive neutron source and a small high-resolution γ detector. The detectors and electronics will benefit from remote unattended operation capabilities resulting from our NEAR XGRS heritage and recent development of a Ge γ detector for MESSENGER. Much of the technology used in this instrument can be adapted to portable or unattended terrestrial applications for detection of explosives, chemical toxins, nuclear weapons, and contraband.

  14. Miniature piezo electric vacuum inlet valve

    DOEpatents

    Keville, R.F.; Dietrich, D.D.

    1998-03-24

    A miniature piezo electric vacuum inlet valve having a fast pulse rate and is battery operated with variable flow capability is disclosed. The low power (<1.6 watts), high pulse rate (<2 milliseconds), variable flow inlet valve is utilized for mass spectroscopic applications or other applications where pulsed or continuous flow conditions are needed. The inlet valve also has a very minimal dead volume of less than 0.01 std/cc. The valve can utilize, for example, a 12 Vdc input/750 Vdc, 3 mA output power supply compared to conventional piezo electric valves which require preloading of the crystal drive mechanism and 120 Vac, thus the valve of the present invention is smaller by a factor of three. 6 figs.

  15. Miniature piezo electric vacuum inlet valve

    DOEpatents

    Keville, Robert F.; Dietrich, Daniel D.

    1998-03-24

    A miniature piezo electric vacuum inlet valve having a fast pulse rate and is battery operated with variable flow capability. The low power (<1.6 watts), high pulse rate (<2 milliseconds), variable flow inlet valve is utilized for mass spectroscopic applications or other applications where pulsed or continuous flow conditions are needed. The inlet valve also has a very minimal dead volume of less than 0.01 std/cc. The valve can utilize, for example, a 12 Vdc input/750 Vdc, 3 mA output power supply compared to conventional piezo electric valves which require preloading of the crystal drive mechanism and 120 Vac, thus the valve of the present invention is smaller by a factor of three.

  16. Miniature Trailing Edge Effector for Aerodynamic Control

    NASA Technical Reports Server (NTRS)

    Lee, Hak-Tae (Inventor); Bieniawski, Stefan R. (Inventor); Kroo, Ilan M. (Inventor)

    2008-01-01

    Improved miniature trailing edge effectors for aerodynamic control are provided. Three types of devices having aerodynamic housings integrated to the trailing edge of an aerodynamic shape are presented, which vary in details of how the control surface can move. A bucket type device has a control surface which is the back part of a C-shaped member having two arms connected by the back section. The C-shaped section is attached to a housing at the ends of the arms, and is rotatable about an axis parallel to the wing trailing edge to provide up, down and neutral states. A flip-up type device has a control surface which rotates about an axis parallel to the wing trailing edge to provide up, down, neutral and brake states. A rotating type device has a control surface which rotates about an axis parallel to the chord line to provide up, down and neutral states.

  17. An automated miniature robotic vehicle inspection system

    SciTech Connect

    Dobie, Gordon; Summan, Rahul; MacLeod, Charles; Pierce, Gareth; Galbraith, Walter

    2014-02-18

    A novel, autonomous reconfigurable robotic inspection system for quantitative NDE mapping is presented. The system consists of a fleet of wireless (802.11g) miniature robotic vehicles, each approximately 175 × 125 × 85 mm with magnetic wheels that enable them to inspect industrial structures such as storage tanks, chimneys and large diameter pipe work. The robots carry one of a number of payloads including a two channel MFL sensor, a 5 MHz dry coupled UT thickness wheel probe and a machine vision camera that images the surface. The system creates an NDE map of the structure overlaying results onto a 3D model in real time. The authors provide an overview of the robot design, data fusion algorithms (positioning and NDE) and visualization software.

  18. Self-folding miniature elastic electric devices

    NASA Astrophysics Data System (ADS)

    Miyashita, Shuhei; Meeker, Laura; Tolley, Michael T.; Wood, Robert J.; Rus, Daniela

    2014-09-01

    Printing functional materials represents a considerable impact on the access to manufacturing technology. In this paper we present a methodology and validation of print-and-self-fold miniature electric devices. Polyvinyl chloride laminated sheets based on metalized polyester film show reliable self-folding processes under a heat application, and it configures 3D electric devices. We exemplify this technique by fabricating fundamental electric devices, namely a resistor, capacitor, and inductor. Namely, we show the development of a self-folded stretchable resistor, variable resistor, capacitive strain sensor, and an actuation mechanism consisting of a folded contractible solenoid coil. Because of their pre-defined kinematic design, these devices feature elasticity, making them suitable as sensors and actuators in flexible circuits. Finally, an RLC circuit obtained from the integration of developed devices is demonstrated, in which the coil based actuator is controlled by reading a capacitive strain sensor.

  19. Miniature solid-state gas compressor

    DOEpatents

    Lawless, W.N.; Cross, L.E.; Steyert, W.A.

    1985-05-07

    A miniature apparatus for compressing gases is disclosed in which an elastomer disposed between two opposing electrostrictive or piezoelectric ceramic blocks, or between a single electrostrictive or piezoelectric ceramic block and a rigid surface, is caused to extrude into or recede from a channel defined adjacent to the elastomer in response to application or removal of an electric field from the blocks. Individual cells of blocks and elastomer are connected to effect a gas compression by peristaltic activation of the individual cells. The apparatus is self-valving in that the first and last cells operate as inlet and outlet valves, respectively. Preferred electrostrictive and piezoelectric ceramic materials are disclosed, and an alternative, non-peristaltic embodiment of the apparatus is described. 9 figs.

  20. Miniature solid-state gas compressor

    DOEpatents

    Lawless, William N.; Cross, Leslie E.; Steyert, William A.

    1985-01-01

    A miniature apparatus for compressing gases is disclosed in which an elastomer disposed between two opposing electrostrictive or piezoelectric ceramic blocks, or between a single electrostrictive or piezoelectric ceramic block and a rigid surface, is caused to extrude into or recede from a channel defined adjacent to the elastomer in response to application or removal of an electric field from the blocks. Individual cells of blocks and elastomer are connected to effect a gas compression by peristaltic activation of the individual cells. The apparatus is self-valving in that the first and last cells operate as inlet and outlet valves, respectively. Preferred electrostrictive and piezoelectric ceramic materials are disclosed, and an alternative, non-peristaltic embodiment of the apparatus is described.

  1. A miniaturized fibrinolytic assay for plasminogen activators

    NASA Technical Reports Server (NTRS)

    Lewis, M. L.; Nachtwey, D. S.; Damron, K. L.

    1991-01-01

    This report describes a micro-clot lysis assay (MCLA) for evaluating fibrinolytic activity of plasminogen activators (PA). Fibrin clots were formed in wells of microtiter plates. Lysis of the clots by PA, indicated by change in turbidity (optical density, OD), was monitored with a microplate reader at five minutes intervals. Log-log plots of PA dilution versus endpoint, the time at which the OD value was halfway between the maximum and minimum value for each well, were linear over a broad range of PA concentrations (2-200 International units/ml). The MCLA is a modification and miniaturization of well established fibrinolytic methods. The significant practical advantages of the MCLA are that it is a simple, relatively sensitive, non-radioactive, quantitative, kinetic, fibrinolytic micro-technique which can be automated.

  2. Miniature Ring-Shaped Peristaltic Pump

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph; Chang, Zensheu; Bao, Xiaoqi; Lih, Shyh-Shiuh

    2004-01-01

    An experimental miniature peristaltic pump exploits piezoelectrically excited flexural waves that travel around a ring: A fluid is carried in the containers formed in the valleys between the peaks of the flexural waves, What sets the present pump apart from other pumps that exploit piezoelectrically excited flexural waves is the ring shape, which makes it possible to take advantage of some of the desirable characteristics of previously developed piezoelectric rotary motors. A major advantage of the circular (in contradistinction to a straight-line) wave path is that the flexural waves do not come to a stop and, instead, keep propagating around the ring. Hence, a significant portion of the excitation energy supplied during each cycle is reused during the next cycle, with the result that the pump operates more effectively than it otherwise would.

  3. Miniature, sub-nanometer resolution Talbot spectrometer.

    PubMed

    Ye, Erika; Atabaki, Amir H; Han, Ningren; Ram, Rajeev J

    2016-06-01

    Miniaturization of optical spectrometers has a significant practical value as it can enable compact, affordable spectroscopic systems for chemical and biological sensing applications. For many applications, the spectrometer must gather light from sources that span a wide range of emission angles and wavelengths. Here, we report a lens-free spectrometer that is simultaneously compact (<0.6  cm3), of high resolution (<1  nm), and has a clear aperture (of 10×10  mm). The wavelength-scale pattern in the dispersive element strongly diffracts the input light to produce non-paraxial mid-field diffraction patterns that are then recorded using an optimally matched image sensor and processed to reconstruct the spectrum.

  4. Miniature reciprocating heat pumps and engines

    NASA Technical Reports Server (NTRS)

    Thiesen, Jack H. (Inventor); Willen, Gary S. (Inventor); Mohling, Robert A. (Inventor)

    2003-01-01

    The present invention discloses a miniature thermodynamic device that can be constructed using standard micro-fabrication techniques. The device can be used to provide cooling, generate power, compress gases, pump fluids and reduce pressure below ambient (operate as a vacuum pump). Embodiments of the invention relating to the production of a cooling effect and the generation of electrical power, change the thermodynamic state of the system by extracting energy from a pressurized fluid. Energy extraction is attained using an expansion process, which is as nearly isentropic as possible for the appropriately chosen fluid. An isentropic expansion occurs when a compressed gas does work to expand, and in the disclosed embodiments, the gas does work by overcoming either an electrostatic or a magnetic force.

  5. A miniaturized pointing mount for Spacelab missions

    NASA Technical Reports Server (NTRS)

    Fritz, C. G.; Howell, T., Jr.; Nicaise, P. D.; Parker, J. R.

    1975-01-01

    A Miniaturized Pointing Mount (MPM) for Spacelab missions is defined and simulation results are described. This mount is proposed to complement the Spacelab Instrument Pointing System (IPS). It uses the same mount isolator concept as the Spacelab IPS but is much more efficient and economical for the accommodation of small shuttle payloads. The MPM is built from star tracker assemblies left over from the Apollo Telescope Mount program thereby assuring low cost and development risk. Simulation results indicate a high level of instrument stability can be expected. The short development time of the MPM would permit it to serve as a precursor to the Spacelab IPS for verifying critical new concepts such as the mount isolation and hold down mechanisms.

  6. Miniature fiber optic surface plasmon resonance biosensors

    NASA Astrophysics Data System (ADS)

    Slavik, Radan; Brynda, Eduard; Homola, Jiri; Ctyroky, Jiri

    1999-01-01

    A novel design of surface plasmon resonance fiber optic sensor is reported which leads to a compact, highly miniaturized sensing element with excellent sensitivity. The sensing device is based on a side-polished single-mode optical fiber with a thin metal overlayer supporting surface plasmon waves. The strength of interaction between a fiber mode and a surface plasmon wave depends strongly on the refractive index near the sensing surface. Therefore, refractive index changes associated with biospecific interaction between antibodies immobilized on the sensor and antigen molecules can be monitored by measuring light intensity variations. Detection of horse radish peroxidase (HRP) of the concentration of 100 ng/ml has been accomplished using the fiber optic sensor with a matrix of monoclonal antibodies against HRP immobilized on the sensor surface.

  7. Micro-miniature roll rate sensor

    NASA Astrophysics Data System (ADS)

    Grant, Jonathan; Nelson, Bruce; Garnes, George

    1989-11-01

    The Phase 2 Micro-Miniature Roll Rate Sensor Program developed an optical centripetal accelerometer that can be tailored to work over a wide range of accelerations. A rate sensing device was developed by measuring centripetal acceleration due to rotation with a proof mass loading a photoelastic sensing element. The acceleration is proportional to the amount of birefringence induced by the load. Development of this technology resulted in construction of a prototype rate sensor targeted for use with the Copperhead munition. The sensors developed in this program can be adjusted for the desired range of operation through changes in width of a photoelastic (plastic) sensing element and/or changes in the amount of proof mass used to load the sensing element. Radial location of the sensor can also be used to control the range.

  8. An automated miniature robotic vehicle inspection system

    NASA Astrophysics Data System (ADS)

    Dobie, Gordon; Summan, Rahul; MacLeod, Charles; Pierce, Gareth; Galbraith, Walter

    2014-02-01

    A novel, autonomous reconfigurable robotic inspection system for quantitative NDE mapping is presented. The system consists of a fleet of wireless (802.11g) miniature robotic vehicles, each approximately 175 × 125 × 85 mm with magnetic wheels that enable them to inspect industrial structures such as storage tanks, chimneys and large diameter pipe work. The robots carry one of a number of payloads including a two channel MFL sensor, a 5 MHz dry coupled UT thickness wheel probe and a machine vision camera that images the surface. The system creates an NDE map of the structure overlaying results onto a 3D model in real time. The authors provide an overview of the robot design, data fusion algorithms (positioning and NDE) and visualization software.

  9. A highly miniaturized NDIR methane sensor

    NASA Astrophysics Data System (ADS)

    Ayerden, N. P.; de Graaf, Ger; Enoksson, Peter; Wolffenbuttel, Reinoud F.

    2016-04-01

    The increasing demand for handheld systems for absorption spectroscopy has triggered the development of microspectrometers at various wavelength ranges. Several MEMS implementations of the light source, interferometer/optical filter, and detector have already been reported in the literature. However, the size of microspectrometers is still limited by the required absorption path length in the sample gas cell. This paper presents a compact MEMS linear-variable optical filter (LVOF) where the resonator cavity of the filter is also used as a sample gas cell to measure the absorption of methane at 3392nm wavelength. The physical resonator cavity length is elongated 62.2-fold, using multiple reflections from highly reflective Bragg mirrors to achieve a sufficiently long effective optical absorption path. Although the LVOF would in principle enable operation as a robust portable microspectrometer, here it is used in a miniaturized NDIR methane sensor for wavelength selection and calibration.

  10. Miniaturized radioisotope solid state power sources

    NASA Astrophysics Data System (ADS)

    Fleurial, J.-P.; Snyder, G. J.; Patel, J.; Herman, J. A.; Caillat, T.; Nesmith, B.; Kolawa, E. A.

    2000-01-01

    Electrical power requirements for the next generation of deep space missions cover a wide range from the kilowatt to the milliwatt. Several of these missions call for the development of compact, low weight, long life, rugged power sources capable of delivering a few milliwatts up to a couple of watts while operating in harsh environments. Advanced solid state thermoelectric microdevices combined with radioisotope heat sources and energy storage devices such as capacitors are ideally suited for these applications. By making use of macroscopic film technology, microgenrators operating across relatively small temperature differences can be conceptualized for a variety of high heat flux or low heat flux heat source configurations. Moreover, by shrinking the size of the thermoelements and increasing their number to several thousands in a single structure, these devices can generate high voltages even at low power outputs that are more compatible with electronic components. Because the miniaturization of state-of-the-art thermoelectric module technology based on Bi2Te3 alloys is limited due to mechanical and manufacturing constraints, we are developing novel microdevices using integrated-circuit type fabrication processes, electrochemical deposition techniques and high thermal conductivity substrate materials. One power source concept is based on several thermoelectric microgenerator modules that are tightly integrated with a 1.1W Radioisotope Heater Unit. Such a system could deliver up to 50mW of electrical power in a small lightweight package of approximately 50 to 60g and 30cm3. An even higher degree of miniaturization and high specific power values (mW/mm3) can be obtained when considering the potential use of radioisotope materials for an alpha-voltaic or a hybrid thermoelectric/alpha-voltaic power source. Some of the technical challenges associated with these concepts are discussed in this paper. .

  11. Miniaturized Autonomous Extravehicular Robotic Camera (Mini AERCam)

    NASA Technical Reports Server (NTRS)

    Fredrickson, Steven E.

    2001-01-01

    The NASA Johnson Space Center (JSC) Engineering Directorate is developing the Autonomous Extravehicular Robotic Camera (AERCam), a low-volume, low-mass free-flying camera system . AERCam project team personnel recently initiated development of a miniaturized version of AERCam known as Mini AERCam. The Mini AERCam target design is a spherical "nanosatellite" free-flyer 7.5 inches in diameter and weighing 1 0 pounds. Mini AERCam is building on the success of the AERCam Sprint STS-87 flight experiment by adding new on-board sensing and processing capabilities while simultaneously reducing volume by 80%. Achieving enhanced capability in a smaller package depends on applying miniaturization technology across virtually all subsystems. Technology innovations being incorporated include micro electromechanical system (MEMS) gyros, "camera-on-a-chip" CMOS imagers, rechargeable xenon gas propulsion system , rechargeable lithium ion battery, custom avionics based on the PowerPC 740 microprocessor, GPS relative navigation, digital radio frequency communications and tracking, micropatch antennas, digital instrumentation, and dense mechanical packaging. The Mini AERCam free-flyer will initially be integrated into an approximate flight-like configuration for demonstration on an airbearing table. A pilot-in-the-loop and hardware-in-the-loop simulation to simulate on-orbit navigation and dynamics will complement the airbearing table demonstration. The Mini AERCam lab demonstration is intended to form the basis for future development of an AERCam flight system that provides beneficial on-orbit views unobtainable from fixed cameras, cameras on robotic manipulators, or cameras carried by EVA crewmembers.

  12. Hairy root culture: bioreactor design and process intensification.

    PubMed

    Stiles, Amanda R; Liu, Chun-Zhao

    2013-01-01

    The cultivation of hairy roots for the production of secondary metabolites offers numerous advantages; hairy roots have a fast growth rate, are genetically stable, and are relatively simple to maintain in phytohormone free media. Hairy roots provide a continuous source of secondary metabolites, and are useful for the production of chemicals for pharmaceuticals, cosmetics, and food additives. In order for hairy roots to be utilized on a commercial scale, it is necessary to scale-up their production. Over the last several decades, significant research has been conducted on the cultivation of hairy roots in various types of bioreactor systems. In this review, we discuss the advantages and disadvantages of various bioreactor systems, the major factors related to large-scale bioreactor cultures, process intensification technologies and overview the mathematical models and computer-aided methods that have been utilized for bioreactor design and development.

  13. Upflow bioreactor with septum and pressure release mechanism

    DOEpatents

    Hansen, Conly L.; Hansen, Carl S.; Pack, Kevin; Milligan, John; Benefiel, Bradley C.; Tolman, C. Wayne; Tolman, Kenneth W.

    2010-04-20

    An upflow bioreactor includes a vessel having an inlet and an outlet configured for upflow operation. A septum is positioned within the vessel and defines a lower chamber and an upper chamber. The septum includes an aperture that provides fluid communication between the upper chamber and lower chamber. The bioreactor also includes means for releasing pressure buildup in the lower chamber. In one configuration, the septum includes a releasable portion having an open position and a closed position. The releasable portion is configured to move to the open position in response to pressure buildup in the lower chamber. In the open position fluid communication between the lower chamber and the upper chamber is increased. Alternatively the lower chamber can include a pressure release line that is selectively actuated by pressure buildup. The pressure release mechanism can prevent the bioreactor from plugging and/or prevent catastrophic damage to the bioreactor caused by high pressures.

  14. Salmonella Typhimurium grown in a rotating wall bioreactor

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Salmonella typhimurium appears green in on human intestinal tissue (stained red) cultured in a NASA rotating wall bioreactor. Dr. Cheryl Nickerson of Tulane University is studying the effects of simulated low-g on a well-known pathogen, Salmonella typhimurium, a bacterium that causes two to four million cases of gastrointestinal illness in the United States each year. While most healthy people recover readily, S. typhimurium can kill people with weakened immune systems. Thus, a simple case of food poisoning could disrupt a space mission. Using the NASA rotating-wall bioreactor, Nickerson cultured S. typhimurium in modeled microgravity. Mice infected with the bacterium died an average of three days faster than the control mice, indicating that S. typhimurium's virulence was enhanced by the bioreactor. Earlier research showed that 3 percent of the genes were altered by exposure to the bioreactor. Nickerson's work earned her a 2001 Presidential Early Career Award for Scientists and Engineers.

  15. EMERGING TECHNOLOGY BULLETIN - METHANOTROPHIC BIOREACTOR SYSTEM - BIOTROL, INC.

    EPA Science Inventory

    BioTrol's Methanotrophic Bioreactor is an above-ground remedial system for water contaminated with halogenated volatile organic compounds, including trichloroethylene (ICE) and related chemicals. Its design features circumvent problems peculiar to treatment of this unique class o...

  16. Hydrofocusing Bioreactor for Three-Dimensional Cell Culture

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R.; Spaulding, Glenn F.; Tsao, Yow-Min D.; Flechsig, Scott; Jones, Leslie; Soehnge, Holly

    2003-01-01

    The hydrodynamic focusing bioreactor (HFB) is a bioreactor system designed for three-dimensional cell culture and tissue-engineering investigations on orbiting spacecraft and in laboratories on Earth. The HFB offers a unique hydrofocusing capability that enables the creation of a low-shear culture environment simultaneously with the "herding" of suspended cells, tissue assemblies, and air bubbles. Under development for use in the Biotechnology Facility on the International Space Station, the HFB has successfully grown large three-dimensional, tissuelike assemblies from anchorage-dependent cells and grown suspension hybridoma cells to high densities. The HFB, based on the principle of hydrodynamic focusing, provides the capability to control the movement of air bubbles and removes them from the bioreactor without degrading the low-shear culture environment or the suspended three-dimensional tissue assemblies. The HFB also provides unparalleled control over the locations of cells and tissues within its bioreactor vessel during operation and sampling.

  17. Microbial community structure and dynamics in a membrane bioreactor supplemented with the flame retardant dibromoneopentyl glycol.

    PubMed

    Zangi-Kotler, Moran; Ben-Dov, Eitan; Tiehm, Andreas; Kushmaro, Ariel

    2015-11-01

    Brominated flame retardants (BFRs) are a group of widely used compounds that, due to their limited biodegradability, exhibit excessive persistence in the environment. The persistence and high toxicity of these compounds to the natural biota causes great environmental concern. We investigated the biodegradation of the BFR dibromoneopentyl glycol (DBNPG) under continuous culture conditions using a miniature membrane bioreactor (mMBR) to assess its feasibility as a bioremediation approach. This system demonstrated long-term, stable biodegradation of DBNPG (>90 days), with an average removal rate of about 50%. Pyrosequencing of the 16S rRNA gene of the microorganisms involved in this process revealed the dominance of reads affiliated with the genus Brevundimonas of the Alphaproteobacteria class during the different mMBR operational stages. The bacterial community was also dominated by reads affiliated with the Sinorhizobium and Sphingopyxis genera within the Alphaproteobacteria class and the Sediminibacterium genus of the Sphingobacteria class. Real-time PCR used to analyze possible changes in the population dynamics of these four dominant groups revealed their consistent presence throughout the long-term mMBR biodegradation activity. Two genera, Brevundimonas and Sphingopyxis, were found to increase in abundance during the acclimation period and then remained relatively stable, forming the main parts of the consortium over the prolonged active stage.

  18. Brain-Region-Specific Organoids Using Mini-bioreactors for Modeling ZIKV Exposure.

    PubMed

    Qian, Xuyu; Nguyen, Ha Nam; Song, Mingxi M; Hadiono, Christopher; Ogden, Sarah C; Hammack, Christy; Yao, Bing; Hamersky, Gregory R; Jacob, Fadi; Zhong, Chun; Yoon, Ki-Jun; Jeang, William; Lin, Li; Li, Yujing; Thakor, Jai; Berg, Daniel A; Zhang, Ce; Kang, Eunchai; Chickering, Michael; Nauen, David; Ho, Cheng-Ying; Wen, Zhexing; Christian, Kimberly M; Shi, Pei-Yong; Maher, Brady J; Wu, Hao; Jin, Peng; Tang, Hengli; Song, Hongjun; Ming, Guo-Li

    2016-05-19

    Cerebral organoids, three-dimensional cultures that model organogenesis, provide a new platform to investigate human brain development. High cost, variability, and tissue heterogeneity limit their broad applications. Here, we developed a miniaturized spinning bioreactor (SpinΩ) to generate forebrain-specific organoids from human iPSCs. These organoids recapitulate key features of human cortical development, including progenitor zone organization, neurogenesis, gene expression, and, notably, a distinct human-specific outer radial glia cell layer. We also developed protocols for midbrain and hypothalamic organoids. Finally, we employed the forebrain organoid platform to model Zika virus (ZIKV) exposure. Quantitative analyses revealed preferential, productive infection of neural progenitors with either African or Asian ZIKV strains. ZIKV infection leads to increased cell death and reduced proliferation, resulting in decreased neuronal cell-layer volume resembling microcephaly. Together, our brain-region-specific organoids and SpinΩ provide an accessible and versatile platform for modeling human brain development and disease and for compound testing, including potential ZIKV antiviral drugs. PMID:27118425

  19. Vortex breakdown in a truncated conical bioreactor

    NASA Astrophysics Data System (ADS)

    Balci, Adnan; Brøns, Morten; Herrada, Miguel A.; Shtern, Vladimir N.

    2015-12-01

    This numerical study explains the eddy formation and disappearance in a slow steady axisymmetric air-water flow in a vertical truncated conical container, driven by the rotating top disk. Numerous topological metamorphoses occur as the water height, Hw, and the bottom-sidewall angle, α, vary. It is found that the sidewall convergence (divergence) from the top to the bottom stimulates (suppresses) the development of vortex breakdown (VB) in both water and air. At α = 60°, the flow topology changes eighteen times as Hw varies. The changes are due to (a) competing effects of AMF (the air meridional flow) and swirl, which drive meridional motions of opposite directions in water, and (b) feedback of water flow on AMF. For small Hw, the AMF effect dominates. As Hw increases, the swirl effect dominates and causes VB. The water flow feedback produces and modifies air eddies. The results are of fundamental interest and can be relevant for aerial bioreactors.

  20. PIV Measurements of Bioreactor Flow Fields

    NASA Astrophysics Data System (ADS)

    Neitzel, G. P.; Brown, J. B.

    1999-11-01

    Spinner-flask bioreactors are operated with several stationary tissue constructs mounted on long needles; the culture medium is stirred by a magnetic stir bar at the vessel bottom. Flow-visualization and PIV measurements have been performed in a scaled-up model system in which the curved, outer vessel wall has been eliminated and the vessel body, culture-medium simulant and tissue-construct models are all index-of-refraction matched. Measurements in the vicinity of the tissue constructs indicate high instantaneous shear stresses at some locations, which may be detrimental to tissue growth. Since the flow is driven by a periodic source, turbulence properties are determined using phase-locked ensemble averaging.

  1. Cardiac tissue engineering using perfusion bioreactor systems

    PubMed Central

    Radisic, Milica; Marsano, Anna; Maidhof, Robert; Wang, Yadong; Vunjak-Novakovic, Gordana

    2009-01-01

    This protocol describes tissue engineering of synchronously contractile cardiac constructs by culturing cardiac cell populations on porous scaffolds (in some cases with an array of channels) and bioreactors with perfusion of culture medium (in some cases supplemented with an oxygen carrier). The overall approach is ‘biomimetic’ in nature as it tends to provide in vivo-like oxygen supply to cultured cells and thereby overcome inherent limitations of diffusional transport in conventional culture systems. In order to mimic the capillary network, cells are cultured on channeled elastomer scaffolds that are perfused with culture medium that can contain oxygen carriers. The overall protocol takes 2–4 weeks, including assembly of the perfusion systems, preparation of scaffolds, cell seeding and cultivation, and on-line and end-point assessment methods. This model is well suited for a wide range of cardiac tissue engineering applications, including the use of human stem cells, and high-fidelity models for biological research. PMID:18388955

  2. Rotating bio-reactor cell culture apparatus

    NASA Technical Reports Server (NTRS)

    Schwarz, Ray P. (Inventor); Wolf, David A. (Inventor)

    1991-01-01

    A bioreactor system is described in which a tubular housing contains an internal circularly disposed set of blade members and a central tubular filter all mounted for rotation about a common horizontal axis and each having independent rotational support and rotational drive mechanisms. The housing, blade members and filter preferably are driven at a constant slow speed for placing a fluid culture medium with discrete microbeads and cell cultures in a discrete spatial suspension in the housing. Replacement fluid medium is symmetrically input and fluid medium is symmetrically output from the housing where the input and the output are part of a loop providing a constant or intermittent flow of fluid medium in a closed loop.

  3. Microbial Bioreactor Development in the ALS NSCORT

    NASA Astrophysics Data System (ADS)

    Mitchell, Cary; Whitaker, Dawn; Banks, M. Katherine; Heber, Albert J.; Turco, Ronald F.; Nies, Loring F.; Alleman, James E.; Sharvelle, Sybil E.; Li, Congna; Heller, Megan

    The NASA Specialized Center of Research and Training in Advanced Life Support (the ALS NSCORT), a partnership of Alabama A & M, Howard, and Purdue Universities, was established by NASA in 2002 to develop technologies that will reduce the Equivalent System Mass (ESM) of regenerative processes within future space life-support systems. A key focus area of NSCORT research has been the development of efficient microbial bioreactors for treatment of human, crop, and food-process wastes while enabling resource recovery. The approach emphasizes optimizing the energy-saving advantages of hydrolytic enzymes for biomass degradation, with focus on treatment of solid wastes including crop residue, paper, food, and human metabolic wastes, treatment of greywater, cabin air, off-gases from other treatment systems, and habitat condensate. This summary includes important findings from those projects, status of technology development, and recommendations for next steps. The Plant-based Anaerobic-Aerobic Bioreactor-Linked Operation (PAABLO) system was developed to reduce crop residue while generating energy and/or food. Plant residues initially were added directly to the bioreactor, and recalcitrant residue was used as a substrate for growing plants or mushrooms. Subsequently, crop residue was first pretreated with fungi to hydrolyze polymers recalcitrant to bacteria, and leachate from the fungal beds was directed to the anaerobic digester. Exoenzymes from the fungi pre-soften fibrous plant materials, improving recovery of materials that are more easily biodegraded to methane that can be used for energy reclamation. An Autothermal Thermophilic Aerobic Digestion (ATAD) system was developed for biodegradable solid wastes. Objectives were to increase water and nutrient recovery, reduce waste volume, and inactivate pathogens. Operational parameters of the reactor were optimized for degradation and resource recovery while minimizing system requirements and footprint. The start-up behavior

  4. Modeling bioaugmentation with nitrifiers in membrane bioreactors.

    PubMed

    Mannucci, Alberto; Munz, Giulio; Mori, Gualtiero; Makinia, Jacek; Lubello, Claudio; Oleszkiewicz, Jan A

    2015-01-01

    Bioaugmentation with nitrifiers was studied using two pilot-scale membrane bioreactors, with the purpose of assessing the suitability of state-of-the-art activated sludge models (ASMs) in predicting the efficiency of bioaugmentation as a function of operating conditions. It was demonstrated that the temperature difference between seeding and seeded reactors (ΔT) affects bioaugmentation efficiency. Experimental data were accurately predicted when ΔT was within a range of up to 10 °C at the higher range, and when the temperature was significantly lower in the seeded reactor compared to the seeding one, standard ASMs overestimated the efficiency of bioaugmentation. A modified ASM, capable of accurately representing the behavior of seeded nitrifying biomass in the presence of high ΔT, would require the inclusion of the effect of temperature time gradients on nitrifiers. A simple linear correlation between ΔT and the Arrhenius coefficient was proposed as a preliminary step.

  5. Production of oncolytic adenovirus and human mesenchymal stem cells in a single-use, Vertical-Wheel bioreactor system: Impact of bioreactor design on performance of microcarrier-based cell culture processes.

    PubMed

    Sousa, Marcos F Q; Silva, Marta M; Giroux, Daniel; Hashimura, Yas; Wesselschmidt, Robin; Lee, Brian; Roldão, António; Carrondo, Manuel J T; Alves, Paula M; Serra, Margarida

    2015-01-01

    Anchorage-dependent cell cultures are used for the production of viruses, viral vectors, and vaccines, as well as for various cell therapies and tissue engineering applications. Most of these applications currently rely on planar technologies for the generation of biological products. However, as new cell therapy product candidates move from clinical trials towards potential commercialization, planar platforms have proven to be inadequate to meet large-scale manufacturing demand. Therefore, a new scalable platform for culturing anchorage-dependent cells at high cell volumetric concentrations is urgently needed. One promising solution is to grow cells on microcarriers suspended in single-use bioreactors. Toward this goal, a novel bioreactor system utilizing an innovative Vertical-Wheel™ technology was evaluated for its potential to support scalable cell culture process development. Two anchorage-dependent human cell types were used: human lung carcinoma cells (A549 cell line) and human bone marrow-derived mesenchymal stem cells (hMSC). Key hydrodynamic parameters such as power input, mixing time, Kolmogorov length scale, and shear stress were estimated. The performance of Vertical-Wheel bioreactors (PBS-VW) was then evaluated for A549 cell growth and oncolytic adenovirus type 5 production as well as for hMSC expansion. Regarding the first cell model, higher cell growth and number of infectious viruses per cell were achieved when compared with stirred tank (ST) bioreactors. For the hMSC model, although higher percentages of proliferative cells could be reached in the PBS-VW compared with ST bioreactors, no significant differences in the cell volumetric concentration and expansion factor were observed. Noteworthy, the hMSC population generated in the PBS-VW showed a significantly lower percentage of apoptotic cells as well as reduced levels of HLA-DR positive cells. Overall, these results showed that process transfer from ST bioreactor to PBS-VW, and scale-up was

  6. Production of oncolytic adenovirus and human mesenchymal stem cells in a single-use, Vertical-Wheel bioreactor system: Impact of bioreactor design on performance of microcarrier-based cell culture processes.

    PubMed

    Sousa, Marcos F Q; Silva, Marta M; Giroux, Daniel; Hashimura, Yas; Wesselschmidt, Robin; Lee, Brian; Roldão, António; Carrondo, Manuel J T; Alves, Paula M; Serra, Margarida

    2015-01-01

    Anchorage-dependent cell cultures are used for the production of viruses, viral vectors, and vaccines, as well as for various cell therapies and tissue engineering applications. Most of these applications currently rely on planar technologies for the generation of biological products. However, as new cell therapy product candidates move from clinical trials towards potential commercialization, planar platforms have proven to be inadequate to meet large-scale manufacturing demand. Therefore, a new scalable platform for culturing anchorage-dependent cells at high cell volumetric concentrations is urgently needed. One promising solution is to grow cells on microcarriers suspended in single-use bioreactors. Toward this goal, a novel bioreactor system utilizing an innovative Vertical-Wheel™ technology was evaluated for its potential to support scalable cell culture process development. Two anchorage-dependent human cell types were used: human lung carcinoma cells (A549 cell line) and human bone marrow-derived mesenchymal stem cells (hMSC). Key hydrodynamic parameters such as power input, mixing time, Kolmogorov length scale, and shear stress were estimated. The performance of Vertical-Wheel bioreactors (PBS-VW) was then evaluated for A549 cell growth and oncolytic adenovirus type 5 production as well as for hMSC expansion. Regarding the first cell model, higher cell growth and number of infectious viruses per cell were achieved when compared with stirred tank (ST) bioreactors. For the hMSC model, although higher percentages of proliferative cells could be reached in the PBS-VW compared with ST bioreactors, no significant differences in the cell volumetric concentration and expansion factor were observed. Noteworthy, the hMSC population generated in the PBS-VW showed a significantly lower percentage of apoptotic cells as well as reduced levels of HLA-DR positive cells. Overall, these results showed that process transfer from ST bioreactor to PBS-VW, and scale-up was

  7. Tissue grown in space in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens of cartilage tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. Constructs grown on Mir (A) tended to become more spherical, whereas those grown on Earth (B) maintained their initial disc shape. These findings might be related to differences in cultivation conditions, i.e., videotapes showed that constructs floated freely in microgravity but settled and collided with the rotating vessel wall at 1g (Earth's gravity). In particular, on Mir the constructs were exposed to uniform shear and mass transfer at all surfaces such that the tissue grew equally in all directions, whereas on Earth the settling of discoid constructs tended to align their flat circular areas perpendicular to the direction of motion, increasing shear and mass transfer circumferentially such that the tissue grew preferentially in the radial direction. A and B are full cross sections of constructs from Mir and Earth groups shown at 10-power. C and D are representative areas at the construct surfaces enlarged to 200-power. They are stained red with safranin-O. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Photo credit: Proceedings of the National Academy of Sciences.

  8. Pinching evidences in a miniature plasma focus with fast pseudospark switch

    NASA Astrophysics Data System (ADS)

    Hassan, S. M.; Zhang, T.; Patran, A.; Rawat, R. S.; Springham, S. V.; Tan, T. L.; Wong, D.; Wang, W.; Lee, S.; Gribkov, V. A.; Mohanty, S. R.; Lee, P.

    2006-11-01

    We report the observations of pinching in a miniature plasma focus (PF) (58—160 J) operated in repetitive mode using fast pseudospark switch (PSS). The size of the device, which includes the capacitor bank, PSS and the focus chamber, is of the order of 22 cm × 22 cm × 38 cm. Several diagnostic tools, the gated imager, streak camera, current and voltage probe, are employed simultaneously to confirm the occurrence of pinching in this fast miniature PF device. The device is optimized for operation in neon and hydrogen as the working gas. The best focus formation was obtained at pressures between 0.5 to 8.0 mbar for neon and between 7.0 to 15.0 mbar for hydrogen. When the system was operated at 100 J with hydrogen as the filling gas, the typical dip in the current derivative signal and the typical peak in the voltage signal associated with pinch compression, are observed to be most intense indicating efficient pinching in the miniature PF device.

  9. A high power density miniaturized microbial fuel cell having carbon nanotube anodes

    NASA Astrophysics Data System (ADS)

    Ren, Hao; Pyo, Soonjae; Lee, Jae-Ik; Park, Tae-Jin; Gittleson, Forrest S.; Leung, Frederick C. C.; Kim, Jongbaeg; Taylor, André D.; Lee, Hyung-Sool; Chae, Junseok

    2015-01-01

    Microbial fuel cells (MFCs) are a promising technology capable of directly converting the abundant biomass on the planet into electricity. Prior studies have adopted a variety of nanostructured materials with high surface area to volume ratio (SAV), yet the current and power density of these nanostructured materials do not deliver a significant leap over conventional MFCs. This study presents a novel approach to implement a miniaturized MFC with a high SAV of 4000 m-1 using three different CNT-based electrode materials: Vertically Aligned CNT (VACNT), Randomly Aligned CNT (RACNT), and Spin-Spray Layer-by-Layer (SSLbL) CNT. These CNT-based electrodes show unique biofilm morphology and thickness. The study of performance parameters of miniaturized MFCs with these CNT-electrodes are conducted with respect to a control bare gold electrode. The results show that CNT-based materials attract more exoelectrogens, Geobacter sp., than bare gold, yielding thicker biofilm formation. Among CNT-based electrodes, low sheet resistance electrodes result in thick biofilm generation and high current/power density. The miniaturized MFC having an SSLbL CNT anode exhibits a high volumetric power density of 3320 W m-3. This research may help lay the foundation for future research involving the optimization of MFCS with 2D and 3D nanostructured electrodes.

  10. Miniature Piezoelectric Compressor for Joule-Thomson Cryocoolers

    NASA Astrophysics Data System (ADS)

    Sobol, Sergey; Tzabar, Nir; Grossman, Gershon

    Joule-Thomson (JT) cryocoolers operate with a continuous flow of the working fluid that enters the cooler at a high pressure and leaves it at a lower pressure. Ideally, the temperature of the outgoing fluid equals the temperature of the entering fluid. JT cryocoolers that operate with pure refrigerants require high pressure of a few tens of MPa where the low pressure is usually around 0.1 MPa. Circulation of the working fluid in such cases requires high pressure ratio compressors that evidently have large dimensions. JT cryocoolers can operate with much lower pressure ratios by using mixed-refrigerants. Cooling from 300 K to about 80 K in a single stage cryocooler normally requires a pressure ratio of about 1:25. In the present research a miniature compressor driven by piezoelectric elements is developed in collaboration between Rafael and the Technion. This type of compressor has the advantage of improved long life compared to other mechanical compressors, very low vibrations, and silent operation. In the current case, the design goal of the intake and discharge pressures has been 0.1 and 2.5 MPa, respectively, with a flow rate of 0.06 g/s. The compressor has two compression stages; 1:5 and 5:25. Several configurations have been considered, fabricated, and tested. The performance of the last configuration approaches the desired specification and is presented in the current paper together with the design concept.

  11. Towards a Standard Mixed-Signal Parallel Processing Architecture for Miniature and Microrobotics

    PubMed Central

    Sadler, Brian M; Hoyos, Sebastian

    2014-01-01

    The conventional analog-to-digital conversion (ADC) and digital signal processing (DSP) architecture has led to major advances in miniature and micro-systems technology over the past several decades. The outlook for these systems is significantly enhanced by advances in sensing, signal processing, communications and control, and the combination of these technologies enables autonomous robotics on the miniature to micro scales. In this article we look at trends in the combination of analog and digital (mixed-signal) processing, and consider a generalized sampling architecture. Employing a parallel analog basis expansion of the input signal, this scalable approach is adaptable and reconfigurable, and is suitable for a large variety of current and future applications in networking, perception, cognition, and control. PMID:26601042

  12. Use of a miniature infrared COTS sensor in a several military applications

    NASA Astrophysics Data System (ADS)

    Kostrzewa, Joseph; Meyer, William H.; Terre, William A.; Laband, Stanley; Newsome, Gwendolyn W.

    2002-08-01

    The proliferation of small infrared cameras in high-volume commercial applications (e.g. firefighting, law-enforcement, and automotive) presents a tremendous opportunity for truly low-cost military micro-sensors. Indigo Systems Corporation's UL3 OmegaTM camera is a commercial off-the-shelf (COTS) thermal imager that offers ultra-small size, light weight, and low power. It employs a 164×120 microbolometer focal plane array (FPA) and is currently entering full-scale production. Furthermore, a 324×240 upgrade is in development. While aimed primarily at the commercial market, small size and low-power consumption make UL3 well-suited for other applications, including miniature unmanned aerial vehicles (UAVs) weapon-sights, and unattended ground sensors (UGS). This paper focuses on the key features of the UL3 family of miniature IR cameras and their utility in soldier systems.

  13. Discovery of skin alkaloids in a miniaturized eleutherodactylid frog from Cuba

    PubMed Central

    Rodríguez, Ariel; Poth, Dennis; Schulz, Stefan; Vences, Miguel

    2011-01-01

    Four phylogenetically independent lineages of frogs are currently known to sequester lipid-soluble skin alkaloids for which a dietary source has been demonstrated. We report here a remarkable fifth such instance, in Eleutherodactylus iberia and Eleutherodactylus orientalis, two species of miniaturized frogs of the family Eleutherodactylidae from Cuba. Six pumiliotoxins and two indolizidines were found in E. iberia, one of the smallest frogs in the world and characterized by a contrasting colour pattern for which we hypothesize an aposematic function. Analyses of stomach content indicated a numerical prevalence of mites with an important proportion of oribatids—a group of arthropods known to contain one of the pumiliotoxins detected in E. iberia. This suggests that miniaturization and specialization to small prey may have favoured the acquisition of dietary skin alkaloids in these amphibians. PMID:21047848

  14. Miniature swept source for point of care Optical Frequency Domain Imaging

    PubMed Central

    Goldberg, Brian D.; Nezam, S.M. Reza Motaghian; Jillella, Priyanka; Bouma, Brett E.; Tearney, Guillermo J.

    2009-01-01

    Point of care (POC) medical technologies require portable, small, robust instrumentation for practical implementation. In their current embodiment, optical frequency domain imaging (OFDI) systems employ large form-factor wavelength-swept lasers, making them impractical in the POC environment. Here, we describe a first step toward a POC OFDI system by demonstrating a miniaturized swept-wavelength source. The laser is based on a tunable optical filter using a reflection grating and a miniature resonant scanning mirror. The laser achieves 75 nm of bandwidth centered at 1340 nm, a 0.24 nm instantaneous line width, a 15.3 kHz repetition rate with 12 mW peak output power, and a 30.4 kHz A-line rate when utilizing forward and backward sweeps. The entire laser system is approximately the size of a deck of cards and can operate on battery power for at least one hour. PMID:19259202

  15. A MEMS-based miniature DNA analysis system

    SciTech Connect

    Northrup, M.A.; Gonzalez, C.; Hadley, D.

    1995-04-25

    We detail the design and development of a miniature thermal cycling instrument for performing the polymerase chain reaction (PCR) that uses microfabricated, silicon-based reaction chambers. The MEMS-based, battery-operated instrument shows significant improvements over commercial thermal cycling instrumentation. Several different biological systems have been amplified and verified with the miniature PCR instrument including the Human Immunodeficiency Virus; both cloned and genomic DNA templates of {beta} globin; and the genetic disease, Cystic Fibrosis from human DNA. The miniaturization of a PCR thermal cycler is the initial module of a fully-integrated portable, low-power, rapid, and highly efficient bioanalytical instrument.

  16. Bioreactors for tissue mass culture: design, characterization, and recent advances.

    PubMed

    Martin, Yves; Vermette, Patrick

    2005-12-01

    This paper reviews reports on three-dimensional mammalian tissue growth in bioreactors and the corresponding mammalian tissue growth requirements. The needs for nutrient and waste removal of several mammalian tissues are reviewed and compared with the environment of many reactors currently in use such as the continuous stirred tank, the hollow fiber, the Couette-Taylor, the airlift, and the rotating-wall reactors developed by NASA. Many studies conclude that oxygen supply appears to be one of the most important factors limiting tissue growth. Various correlations to describe oxygen mass transfer are presented and discussed with the aim to provide some guidance to design, construct, and test reactors for tissue mass culture. To obtain tissue thickness clinically valuable, dimensionless and other types of analysis tend to point out that diffusive transport will have to be matched with an important convection to bring sufficient oxygen molecular flux to the growing cells located within a tissue mass. As learned from solid-state fermentation and hairy root culture, during the growth of large biomass, heterogeneity (i.e., channeling, temperature gradients, non-uniform cell growth, transfer gradients, etc.) can cause some important problems and these should be addressed in tissue engineering as well. Reactors (along with the scaffolds) should be designed to minimize these issues. The role of the uterus, the reactor built by Nature, is examined, and the environment provided to a growing embryo is reported, yielding possible paths for further reactor developments. Finally, the importance of cell seeding methods is also addressed.

  17. Development of autonomous control in a closed microbial bioreactor.

    PubMed

    Smernoff, D T; Mancinelli, R L

    1999-01-01

    Space-based life support systems which include ecological components will rely on sophisticated hardware and software to monitor and control key system parameters. Autonomous closed artificial ecosystems are useful for research in numerous fields. We are developing a bioreactor designed to study both microbe-environment interactions and autonomous control systems. Currently we are investigating N-cycling and N-mass balance in closed microbial systems. The design features of the system involve real-time monitoring of physical parameters (e.g. temperature, light), growth solution composition (e.g. pH, NOx, CO2), cell density and the status of important hardware components. Control of key system parameters is achieved by incorporation of artificial intelligence software tools that permit autonomous decision-making by the instrument. These developments provide a valuable research tool for terrestrial microbial ecology, as well as a testbed for implementation of artificial intelligence concepts. Autonomous instrumentation will be necessary for robust operation of space-based life support systems, and for use on robotic spacecraft. Sample data acquired from the system, important features of software components, and potential applications for terrestrial and space research will be presented.

  18. Miniature Dual-Corona Ionizer for Bipolar Charging of Aerosol

    PubMed Central

    Qi, Chaolong; Kulkarni, Pramod

    2015-01-01

    A corona-based bipolar charger has been developed for use in compact, field-portable mobility size spectrometers. The charger employs an aerosol flow cavity exposed to two corona ionizers producing ions of opposite polarity. Each corona ionizer houses two electrodes in parallel needle-mesh configuration and is operated at the same magnitude of corona current. Experimental measurement of detailed charge distribution of near-monodisperse particles of different diameter in the submicrometer size range showed that the charger is capable of producing well-defined, consistent bipolar charge distributions for flow rates up to 1.5 L/min and aerosol concentration up to 107 per cm3. For particles with preexisting charge of +1, 0, and −1, the measured charge distributions agreed well with the theoretical distributions within the range of experimental and theoretical uncertainties. The transmission efficiency of the charger was measured to be 80% for 10 nm particles (at 0.3 L/min and 5 μA corona current) and increased with increasing diameter beyond this size. Measurement of uncharged fractions at various combinations of positive and negative corona currents showed the charger performance to be insensitive to fluctuations in corona current. Ion concentrations under positive and negative unipolar operation were estimated to be 8.2 × 107 and 3.37 × 108 cm−3 for positive and negative ions; the n·t product value under positive corona operation was independently estimated to be 8.5 × 105 s/cm3. The ion concentration estimates indicate the charger to be capable of “neutralizing” typical atmospheric and industrial aerosols in most measurement applications. The miniature size, simple and robust operation makes the charger suitable for portable mobility spectrometers. PMID:26512158

  19. Pneumatically Actuated Miniature Peristaltic Vacuum Pumps

    NASA Technical Reports Server (NTRS)

    Feldman, Sabrina; Feldman, Jason; Svehla, Danielle

    2003-01-01

    Pneumatically actuated miniature peristaltic vacuum pumps have been proposed for incorporation into advanced miniature versions of scientific instruments that depend on vacuum for proper operation. These pumps are expected to be capable of reaching vacuum-side pressures in the torr to millitorr range (from .133 down to .0.13 Pa). Vacuum pumps that operate in this range are often denoted roughing pumps. In comparison with previously available roughing pumps, these pumps are expected to be an order of magnitude less massive and less power-hungry. In addition, they would be extremely robust, and would operate with little or no maintenance and without need for oil or other lubricants. Portable mass spectrometers are typical examples of instruments that could incorporate the proposed pumps. In addition, the proposed pumps could be used as roughing pumps in general laboratory applications in which low pumping rates could be tolerated. The proposed pumps could be designed and fabricated in conventionally machined and micromachined versions. A typical micromachined version (see figure) would include a rigid glass, metal, or plastic substrate and two layers of silicone rubber. The bottom silicone layer would contain shallow pump channels covered by silicone arches that could be pushed down pneumatically to block the channels. The bottom silicone layer would be covered with a thin layer of material with very low gas permeability, and would be bonded to the substrate everywhere except in the channel areas. The top silicone layer would be attached to the bottom silicone layer and would contain pneumatic- actuation channels that would lie crosswise to the pump channels. This version is said to be micromachined because the two silicone layers containing the channels would be fabricated by casting silicone rubber on micromachined silicon molds. The pneumatic-actuation channels would be alternately connected to a compressed gas and (depending on pump design) either to atmospheric

  20. Modeling the microbial growth and temperature profile in a fixed-bed bioreactor.

    PubMed

    da Silveira, Christian L; Mazutti, Marcio A; Salau, Nina P G

    2014-10-01

    Aiming to scale up and apply control and optimization strategies, currently is required the development of accurate plant models to forecast the process nonlinear dynamics. In this work, a mathematical model to predict the growth of the Kluyveromyces marxianus and temperature profile in a fixed-bed bioreactor for solid-state fermentation using sugarcane bagasse as substrate was built up. A parameter estimation technique was performed to fit the mathematical model to the experimental data. The estimated parameters and the model fitness were evaluated with statistical analyses. The results have shown the estimated parameters significance, with 95 % confidence intervals, and the good quality of process model to reproduce the experimental data.

  1. A Miniature Controllable Flapping Wing Robot

    NASA Astrophysics Data System (ADS)

    Arabagi, Veaceslav Gheorghe

    The agility and miniature size of nature's flapping wing fliers has long baffled researchers, inspiring biological studies, aerodynamic simulations, and attempts to engineer their robotic replicas. Flapping wing flight is characterized by complex reciprocating wing kinematics, transient aerodynamic effects, and very small body lengths. These characteristics render robotic flapping wing aerial vehicles ideal for surveillance and defense applications, search and rescue missions, and environment monitoring, where their ability to hover and high maneuverability is immensely beneficial. One of the many difficulties in creating flapping wing based miniature robotic aerial vehicles lies in generating a proper wing trajectory that would result in sufficient lift forces for hovering and maneuvering. Since design of a flapping wing system is a balance between overall weight and the number of actuated inputs, we take the approach of having minimal controlled inputs, allowing passive behavior wherever possible. Hence, we propose a completely passive wing pitch reversal design that relies on wing inertial dynamics, an elastic energy storage mechanism, and low Reynolds number aerodynamic effects. Theoretical models, compiling previous research on piezoelectric actuators, four-bar transmissions, and aerodynamics effects, are developed and used as basis for a complete numerical simulation. Limitations of the model are discussed in comparison to experimental results obtained from a working prototype of the proposed passive pitch reversal flapping wing mechanism. Given that the mechanism is under-actuated, methods to control lift force generation by actively varying system parameters are proposed, discussed, and tested experimentally. A dual wing aerial platform is developed based on the passive pitch reversal wing concept. Design considerations are presented, favoring controllability and structural rigidity of the final platform. Finite element analysis and experimental

  2. Laboratory assessment of a miniature electromagnetic tracker

    NASA Astrophysics Data System (ADS)

    Hummel, Johann; Birkfellner, Wolfgang; Figl, Michael; Haider, C.; Hanel, Rudolf A.; Bergmann, Helmar

    2002-05-01

    With the invention of miniaturized electromagnetic digitizers comes a variety of potential clinical applications for computer aided interventions using flexible instruments; it has become possible to track endoscopes or catheters within the body. To evaluate the reliability of a new commercial tracking system, we measured the systematic distortions induced by various materials such as closed metallic loops, wire guides, catheters and ultrasound scan heads. The system under evaluation was the electromagnetic tracking system Aurora (Mednetix/CH, NDI/Can); data were acquired using the serial port of a PC running SuSE Linux 7.1 (SuSE, Gmbh, Nuernberg). The objects suspected to cause distortions were brought into the digitizer volume. Beside this, we evaluated the influence of a C-arm fluoroscopy unit. To quantify the reliability of the system, the miniaturized sensor was mounted on a nonmetallic measurement rack while the transmitter was fixed at three different distances within the digitizer range. The tracker is more sensitive to distortions caused by materials close to the emitter (average value 13.6 mm +/- 16.6mm) for wire loops positioned at a distance between 100 mm and 200 mm from the emitter). Distortions caused by materials near the sensor (distances smaller than 100 mm) are small (typical error: 2.2 mm +/- 1.9 mm) in comparison to the errors of other electromagnetic systems published in an earlier study of our group where we found an average error of 3.4 mm. Considerable distortions are caused by the C-arm fluoroscopy unit and limits the reliability of the tracker (error: 18.6 mm +/- 24.9 mm). The US scan head was found to cause significant distortions only at a distance between the emitter and the scan head less than 100 mm from the emitter in contrast to the average error of 3.8 mm +/- 6.3 mm at distances greater than 100 mm. Taking into account that significant distortions only occur in the presence of metallic objects close to the emitter, these results

  3. The determination of particulate contamination in miniature ball bearings

    SciTech Connect

    Harding, W.B.

    1992-12-01

    A method is described for determining the particulate contamination in miniature ball bearings in which the bearing is flushed with a solvent that is then filtered. The particles that are collected on the filter are examined by optical microscopy.

  4. An Investigation Into the Performance of a Miniature Diesel Engine

    ERIC Educational Resources Information Center

    Stevenson, P. W.

    1970-01-01

    Reports the procedures and results of a student investigation of the performance of a miniature diesel engine. The experiments include (1) torque measurement, (2) power measurement, and (3) variation of power output with applied load. Bibliography. (LC)

  5. Miniature Tractor Pull Helps Teach Mechanical Power Transmission.

    ERIC Educational Resources Information Center

    Waggoner, Todd C.

    1996-01-01

    A miniature tractor pull was developed as a high school activity, enabling students to assess a tractor's pulling capabilities and determine subsequent horsepower. The activity takes the textbook concept of horsepower and makes it come alive. (JOW)

  6. Miniature paint-spray gun for recessed areas

    NASA Technical Reports Server (NTRS)

    Vanasse, M. A.

    1968-01-01

    Miniature spray gun regulates paints and other liquids to spray at close range, facilitating spraying of remote or recessed areas. Individual valves for regulating air pressure and paint maximizes atomization for low pressure spraying.

  7. Miniature oxygen-hydrogen cutting torch constructed from hypodermic needle

    NASA Technical Reports Server (NTRS)

    Shlichta, P.

    1964-01-01

    A miniature cutting torch consisting of a main body member, upon which the hydrogen and oxygen containers are mounted, valves for controlling gas flow, and a hypodermic needle that acts as a mixing tube and flame tip is constructed.

  8. Miniaturized biological and electrochemical fuel cells: challenges and applications.

    PubMed

    Yang, Jie; Ghobadian, Sasan; Goodrich, Payton J; Montazami, Reza; Hashemi, Nastaran

    2013-09-14

    This paper discusses the fundamentals and developments of miniaturized fuel cells, both biological and electrochemical. An overview of microfluidic fuel cells, miniaturized microbial fuel cells, enzymatic biofuel cells, and implanted biofuel cells in an attempt to provide green energy and to power implanted microdevices is provided. Also, the challenges and applications of each type of fuel cell are discussed in detail. Most recent developments in fuel cell technologies such as novel catalysts, compact designs, and fabrication methods are reviewed.

  9. Modular bioreactor for the remediation of liquid streams and methods for using the same

    DOEpatents

    Noah, K.S.; Sayer, R.L.; Thompson, D.N.

    1998-06-30

    The present invention is directed to a bioreactor system for the remediation of contaminated liquid streams. The bioreactor system is composed of at least one and often a series of sub-units referred to as bioreactor modules. The modular nature of the system allows bioreactor systems be subdivided into smaller units and transported to waste sites where they are combined to form bioreactor systems of any size. The bioreactor modules further comprises reactor fill materials in the bioreactor module that remove the contaminants from the contaminated stream. To ensure that the stream thoroughly contacts the reactor fill materials, each bioreactor module comprises means for directing the flow of the stream in a vertical direction and means for directing the flow of the stream in a horizontal direction. In a preferred embodiment, the reactor fill comprises a sulfate reducing bacteria which is particularly useful for precipitating metals from acid mine streams. 6 figs.

  10. Modular bioreactor for the remediation of liquid streams and methods for using the same

    DOEpatents

    Noah, Karl S.; Sayer, Raymond L.; Thompson, David N.

    1998-01-01

    The present invention is directed to a bioreactor system for the remediation of contaminated liquid streams. The bioreactor system is composed of at least one and often a series of sub-units referred to as bioreactor modules. The modular nature of the system allows bioreactor systems be subdivided into smaller units and transported to waste sites where they are combined to form bioreactor systems of any size. The bioreactor modules further comprises reactor fill materials in the bioreactor module that remove the contaminants from the contaminated stream. To ensure that the stream thoroughly contacts the reactor fill materials, each bioreactor module comprises means for directing the flow of the stream in a vertical direction and means for directing the flow of the stream in a horizontal direction. In a preferred embodiment, the reactor fill comprises a sulfate reducing bacteria which is particularly useful for precipitating metals from acid mine streams.

  11. A Novel Miniature Wide-band Radiometer for Space Applications

    NASA Astrophysics Data System (ADS)

    Sykulska-Lawrence, Hanna

    2016-10-01

    Design, development and testing of a novel miniaturised infrared radiometer is described. The instrument opens up new possibilities in planetary science of deployment on smaller platforms – such as unmanned aerial vehicles and microprobes – to enable study of a planet's radiation balance, as well as terrestrial volcano plumes and trace gases in planetary atmospheres, using low-cost long-term observations. Thus a key enabling development is that of miniaturised, low-power and well-calibrated instrumentation.The paper reports advances in miniature technology to perform high accuracy visible / IR remote sensing measurements. The infrared radiometer is akin to those widely used for remote sensing for earth and space applications, which are currently either large instruments on orbiting platforms or medium-sized payloads on balloons. We use MEMS microfabrication techniques to shrink a conventional design, while combining the calibration benefits of large (>1kg) type radiometers with the flexibility and portability of a <10g device. The instrument measures broadband (0.2 to 100um) upward and downward radiation fluxes, with built-in calibration capability, incorporating traceability to temperature standards such as ITS-90.The miniature instrument described here was derived from a concept developed for a European Space Agency study, Dalomis (Proc. of 'i-SAIRAS 2005', Munich, 2005), which involved dropping multiple probes into the atmosphere of Venus from a balloon to sample numerous parts of the complex weather systems on the planet. Data from such an in-situ instrument would complement information from a satellite remote sensing instrument or balloon radiosonde. Moreover, the addition of an internal calibration standard facilitates comparisons between datasets.One of the main challenges for a reduced size device is calibration. We use an in-situ method whereby a blackbody source is integrated within the device and a micromirror switches the input to the detector

  12. CRUQS: A Miniature Fine Sun Sensor for Nanosatellites

    NASA Technical Reports Server (NTRS)

    Heatwole, Scott; Snow, Carl; Santos, Luis

    2013-01-01

    A new miniature fine Sun sensor has been developed that uses a quadrant photodiode and housing to determine the Sun vector. Its size, mass, and power make it especially suited to small satellite applications, especially nanosatellites. Its accuracy is on the order of one arcminute, and it will enable new science in the area of nanosatellites. The motivation for this innovation was the need for high-performance Sun sensors in the nanosatellite category. The design idea comes out of the LISS (Lockheed Intermediate Sun Sensor) used by the sounding rocket program on their solar pointing ACS (Attitude Control System). This system uses photodiodes and a wall between them. The shadow cast by the Sun is used to determine the Sun angle. The new sensor takes this concept and miniaturizes it. A cruciform shaped housing and a surface-mount quadrant photodiode package allow for a two-axis fine Sun sensor to be packaged into a space approx.1.25xl x0.25 in. (approx.3.2x2.5x0.6 cm). The circuitry to read the photodiodes is a simple trans-impedance operational amplifier. This is much less complex than current small Sun sensors for nanosatellites that rely on photo-arrays and processing of images to determine the Sun center. The simplicity of the circuit allows for a low power draw as well. The sensor consists of housing with a cruciform machined in it. The cruciform walls are 0.5-mm thick and the center of the cruciform is situated over the center of the quadrant photodiode sensor. This allows for shadows to be cast on each of the four photodiodes based on the angle of the Sun. A simple operational amplifier circuit is used to read the output of the photodiodes as a voltage. The voltage output of each photodiode is summed based on rows and columns, and then the values of both rows or both columns are differenced and divided by the sum of the voltages for all four photodiodes. The value of both difference over sums for the rows and columns is compared to a table or a polynomial fit

  13. Miniature detector measures deep space radiation

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2011-08-01

    The 1972 journey of Apollo 17 marked not only the last time a human walked on the Moon but also the most recent manned venture beyond the outer reaches of the Earth's atmosphere. With preparations being made for humans to once again explore deep space, important steps are under way to quantify the hazards of leaving low-Earth orbit. One significant risk for long-distance missions is the increased exposure to ionizing radiation—energetic particles that can strip electrons off of otherwise neutral materials, affecting human health and the functioning of spacecraft equipment. The deep space probes that are being sent to measure the risks from ionizing radiation and other hazards can be costly, so maximizing the scientific value of each launch is important. With this goal in mind, Mazur et al. designed and developed a miniature dosimeter that was sent into lunar orbit aboard NASA's Lunar Reconnaissance Orbiter (LRO) in 2009. Weighing only 20 grams, the detector is able to measure fluctuations in ionizing radiation as low as 1 microrad (equivalent to 1.0 × 10-8 joules of energy deposited into 1 kilogram) while requiring minimal power and computer processing. The postage stamp-sized detector tracked radiation dosages for the first year of LRO's mission, with the results being confirmed by other onboard and near-Earth detectors. (Space Weather, doi:10.1029/2010SW000641, 2011)

  14. Design considerations for miniaturized optical neural probes

    NASA Astrophysics Data System (ADS)

    Rudmann, Linda; Ordonez, Juan S.; Stieglitz, Thomas

    2016-03-01

    Neural probes are designed to selectively record from or stimulate nerve cells. In optogenetics it is desirable to build miniaturized and long-term stable optical neural probes, in which the light sources can be directly and chronically implanted into the animals to allow free movement and behavior. Because of the size and the beam shape of the available light sources, it is difficult to target single cells as well as spatially localized networks. We therefore investigated design considerations for packages, which encapsulate the light source hermetically and have integrated hemispherical lens structures that enable to focus the light onto the desired region, by optical simulations. Integration of a biconvex lens into the package lid (diameter = 300 μm, material: silicon carbide) increased the averaged absolute irradiance ηA by 298 % compared to a system without a lens and had a spot size of around 120 μm. Solely integrating a plano-convex lens (same diameter and material) results in an ηA of up to 227 %.

  15. Computational investigation of miniature trailing edge effectors

    NASA Astrophysics Data System (ADS)

    Lee, Hak-Tae

    Miniature trailing edge effectors (MiTEs) are small flaps (typically 1% to 5% chord) actuated with deflection angles of up to 90 degrees. The small size, combined with little required power and good control authority, enables the device to be used for high bandwidth control as well as conventional attitude control. However, some of the aerodynamic characteristics of these devices are complex and poorly understood. This research investigated the aerodynamics of MiTEs using incompressible Navier-Stokes flow solvers, INS2D and INS3D. To understand the flow structure and establish a parametric database, two dimensional steady-state computations were performed for MiTEs with various geometries and flow conditions. Time accurate computations were used to resolve the unsteady characteristics including transient response and vortex shedding phenomena. The frequency response was studied to fully identify the dynamics of MiTEs. Three dimensional computations show the change in control effectiveness with respect to the spanwise length of MiTEs as well as the spanwise lift distribution induced by these devices. Based on the CFD results, an approximate vortex panel model was developed for design purposes that reproduces the key characteristics of MiTEs. Two application areas for MiTEs were explored. Flutter suppression was demonstrated by combining a finite element structural model with the vortex panel model. The application of MiTEs to augment maximum lift and improve the post stall behavior of an airfoil was also investigated.

  16. Miniaturization and globalization of clinical laboratory activities.

    PubMed

    Melo, Murilo R; Clark, Samantha; Barrio, Daniel

    2011-04-01

    Clinical laboratories provide an invaluable service to millions of people around the world in the form of quality diagnostic care. Within the clinical laboratory industry the impetus for change has come from technological development (miniaturization, nanotechnology, and their collective effect on point-of-care testing; POCT) and the increasingly global nature of laboratory services. Potential technological gains in POCT include: the development of bio-sensors, microarrays, genetics and proteomics testing, and enhanced web connectivity. In globalization, prospective opportunities lie in: medical tourism, the migration of healthcare workers, cross-border delivery of testing, and the establishment of accredited laboratories in previously unexplored markets. Accompanying these impressive opportunities are equally imposing challenges. Difficulty transitioning from research to clinical use, poor infrastructure in developing countries, cultural differences and national barriers to global trade are only a few examples. Dealing with the issues presented by globalization and the impact of developing technology on POCT, and on the clinical laboratory services industry in general, will be a daunting task. Despite such concerns, with appropriate countermeasures it will be possible to address the challenges posed. Future laboratory success will be largely dependent on one's ability to adapt in this perpetually shifting landscape.

  17. A locust-inspired miniature jumping robot.

    PubMed

    Zaitsev, Valentin; Gvirsman, Omer; Ben Hanan, Uri; Weiss, Avi; Ayali, Amir; Kosa, Gabor

    2015-12-01

    Unmanned ground vehicles are mostly wheeled, tracked, or legged. These locomotion mechanisms have a limited ability to traverse rough terrain and obstacles that are higher than the robot's center of mass. In order to improve the mobility of small robots it is necessary to expand the variety of their motion gaits. Jumping is one of nature's solutions to the challenge of mobility in difficult terrain. The desert locust is the model for the presented bio-inspired design of a jumping mechanism for a small mobile robot. The basic mechanism is similar to that of the semilunar process in the hind legs of the locust, and is based on the cocking of a torsional spring by wrapping a tendon-like wire around the shaft of a miniature motor. In this study we present the jumping mechanism design, and the manufacturing and performance analysis of two demonstrator prototypes. The most advanced jumping robot demonstrator is power autonomous, weighs 23 gr, and is capable of jumping to a height of 3.35 m, covering a distance of 1.37 m. PMID:26602094

  18. Miniaturized Technologies for Enhancement of Motor Plasticity.

    PubMed

    Moorjani, Samira

    2016-01-01

    The idea that the damaged brain can functionally reorganize itself - so when one part fails, there lies the possibility for another to substitute - is an exciting discovery of the twentieth century. We now know that motor circuits once presumed to be hardwired are not, and motor-skill learning, exercise, and even mental rehearsal of motor tasks can turn genes on or off to shape brain architecture, function, and, consequently, behavior. This is a very significant alteration from our previously static view of the brain and has profound implications for the rescue of function after a motor injury. Presentation of the right cues, applied in relevant spatiotemporal geometries, is required to awaken the dormant plastic forces essential for repair. The focus of this review is to highlight some of the recent progress in neural interfaces designed to harness motor plasticity, and the role of miniaturization in development of strategies that engage diverse elements of the neuronal machinery to synergistically facilitate recovery of function after motor damage. PMID:27148525

  19. Miniature thermo-electric cooled cryogenic pump

    DOEpatents

    Keville, Robert F.

    1997-01-01

    A miniature thermo-electric cooled cryogenic pump for removing residual water molecules from an inlet sample prior to sample analysis in a mass spectroscopy system, such as ion cyclotron resonance (ICR) mass spectroscopy. The cryogenic pump is a battery operated, low power (<1.6 watts) pump with a .DELTA.T=100.degree. C. characteristic. The pump operates under vacuum pressures of 5.times.10.sup.-4 Torr to ultra high vacuum (UHV) conditions in the range of 1.times.10.sup.-7 to 3.times.10.sup.-9 Torr and will typically remove partial pressure, 2.times.10.sup.-7 Torr, residual water vapor. The cryogenic pump basically consists of an inlet flange piece, a copper heat sink with a square internal bore, four two tier Peltier (TEC) chips, a copper low temperature square cross sectional tubulation, an electronic receptacle, and an exit flange piece, with the low temperature tubulation being retained in the heat sink at a bias angle of 5.degree., and with the TECs being positioned in parallel to each other with a positive potential being applied to the top tier thereof.

  20. Miniaturized Blue Laser using Second Harmonic Generation

    NASA Astrophysics Data System (ADS)

    Kitaoka, Yasuo; Yokoyama, Toshifumi; Mizuuchi, Kiminori; Yamamoto, Kazuhisa

    2000-06-01

    We demonstrate a miniaturized blue laser (5× 12× 1.5 mm3) using second harmonic generation (SHG), which consists of a quasi-phase-matched (QPM)-SHG waveguide device on an x-cut Mg-doped LiNbO3 substrate and a tunable distributed-Bragg-reflector (DBR) laser diode. By using the QPM-SHG waveguide device on an x-cut substrate, efficient optical coupling was realized without a half-wave plate, and the maximum coupling efficiency of 75% was achieved. The blue light power of 2 mW was generated for the fundamental coupling power of 20 mW, which agreed with a conversion efficiency of 10%. The mechanical stability of the planar-type butt-coupled SHG blue laser was examined, where the coupling efficiency was maintained constantly under the change of module temperature and the temperature cycle test from 10 to 60°C. We succeeded in downsizing the SHG blue laser to 0.1 cm3, which is sufficiently small for its application to optical disk systems.

  1. Miniaturized 3D microscope imaging system

    NASA Astrophysics Data System (ADS)

    Lan, Yung-Sung; Chang, Chir-Weei; Sung, Hsin-Yueh; Wang, Yen-Chang; Chang, Cheng-Yi

    2015-05-01

    We designed and assembled a portable 3-D miniature microscopic image system with the size of 35x35x105 mm3 . By integrating a microlens array (MLA) into the optical train of a handheld microscope, the biological specimen's image will be captured for ease of use in a single shot. With the light field raw data and program, the focal plane can be changed digitally and the 3-D image can be reconstructed after the image was taken. To localize an object in a 3-D volume, an automated data analysis algorithm to precisely distinguish profundity position is needed. The ability to create focal stacks from a single image allows moving or specimens to be recorded. Applying light field microscope algorithm to these focal stacks, a set of cross sections will be produced, which can be visualized using 3-D rendering. Furthermore, we have developed a series of design rules in order to enhance the pixel using efficiency and reduce the crosstalk between each microlens for obtain good image quality. In this paper, we demonstrate a handheld light field microscope (HLFM) to distinguish two different color fluorescence particles separated by a cover glass in a 600um range, show its focal stacks, and 3-D position.

  2. Development of a Prototype Miniature Silicon Microgyroscope

    PubMed Central

    Xia, Dunzhu; Chen, Shuling; Wang, Shourong

    2009-01-01

    A miniature vacuum-packaged silicon microgyroscope (SMG) with symmetrical and decoupled structure was designed to prevent unintended coupling between drive and sense modes. To ensure high resonant stability and strong disturbance resisting capacity, a self-oscillating closed-loop circuit including an automatic gain control (AGC) loop based on electrostatic force feedback is adopted in drive mode, while, dual-channel decomposition and reconstruction closed loops are applied in sense mode. Moreover, the temperature effect on its zero bias was characterized experimentally and a practical compensation method is given. The testing results demonstrate that the useful signal and quadrature signal will not interact with each other because their phases are decoupled. Under a scale factor condition of 9.6 mV/°/s, in full measurement range of ± 300 deg/s, the zero bias stability reaches 15°/h with worse-case nonlinearity of 400 ppm, and the temperature variation trend of the SMG bias is thus largely eliminated, so that the maximum bias value is reduced to one tenth of the original after compensation from -40 °C to 80 °C. PMID:22408543

  3. A new miniaturized atomic magnetic gradiometer

    NASA Astrophysics Data System (ADS)

    Sheng, Dong; Perry, Abigail; Krzyzewski, Sean; Geller, Shawn; Knappe, Svenja; Kitching, John

    2016-05-01

    We report the development of a new miniaturized magnetic gradiometer using alkali atoms. The gradiometer, with the length of 5 cm and cross section diameter of 11 mm, is made of two chip-scale atomic magnetometers placed on a printed optical bench with a defined separation. Both magnetometers work in the spin-exchange relaxation free regime, share the same beam for pumping and probing to reduce the common mode noises from the lasers, and atom temperature is independently controlled by heating beams at telecom wavelength. With 2 cm baseline, 1 mW pumping beam power, and less than 400 mW input heating beam power, we measure a noise level of 15 fT/ Hz1/2 from the subtraction of two magnetometer outputs, which corresponds to a gradient field sensitivity of 7.5 fT/ Hz1/2/cm. The maximum common mode magnetic field noise rejection is up to 1000 within the gradiometer bandwidth. This device is useful in many fields that require both sensitive gradient field information and high common mode noise cancellation. We are also developing a new hybrid system based on this device to improve its dynamical range.

  4. Miniaturized Technologies for Enhancement of Motor Plasticity

    PubMed Central

    Moorjani, Samira

    2016-01-01

    The idea that the damaged brain can functionally reorganize itself – so when one part fails, there lies the possibility for another to substitute – is an exciting discovery of the twentieth century. We now know that motor circuits once presumed to be hardwired are not, and motor-skill learning, exercise, and even mental rehearsal of motor tasks can turn genes on or off to shape brain architecture, function, and, consequently, behavior. This is a very significant alteration from our previously static view of the brain and has profound implications for the rescue of function after a motor injury. Presentation of the right cues, applied in relevant spatiotemporal geometries, is required to awaken the dormant plastic forces essential for repair. The focus of this review is to highlight some of the recent progress in neural interfaces designed to harness motor plasticity, and the role of miniaturization in development of strategies that engage diverse elements of the neuronal machinery to synergistically facilitate recovery of function after motor damage. PMID:27148525

  5. Miniature thermo-electric cooled cryogenic pump

    DOEpatents

    Keville, R.F.

    1997-11-18

    A miniature thermo-electric cooled cryogenic pump is described for removing residual water molecules from an inlet sample prior to sample analysis in a mass spectroscopy system, such as ion cyclotron resonance (ICR) mass spectroscopy. The cryogenic pump is a battery operated, low power (<1.6 watts) pump with a {Delta}T=100 C characteristic. The pump operates under vacuum pressures of 5{times}10{sup {minus}4} Torr to ultra high vacuum (UHV) conditions in the range of 1{times}10{sup {minus}7} to 3{times}10{sup {minus}9} Torr and will typically remove partial pressure, 2{times}10{sup {minus}7} Torr, residual water vapor. The cryogenic pump basically consists of an inlet flange piece, a copper heat sink with a square internal bore, four two tier Peltier (TEC) chips, a copper low temperature square cross sectional tubulation, an electronic receptacle, and an exit flange piece, with the low temperature tubulation being retained in the heat sink at a bias angle of 5{degree}, and with the TECs being positioned in parallel to each other with a positive potential being applied to the top tier thereof. 2 figs.

  6. A locust-inspired miniature jumping robot.

    PubMed

    Zaitsev, Valentin; Gvirsman, Omer; Ben Hanan, Uri; Weiss, Avi; Ayali, Amir; Kosa, Gabor

    2015-11-25

    Unmanned ground vehicles are mostly wheeled, tracked, or legged. These locomotion mechanisms have a limited ability to traverse rough terrain and obstacles that are higher than the robot's center of mass. In order to improve the mobility of small robots it is necessary to expand the variety of their motion gaits. Jumping is one of nature's solutions to the challenge of mobility in difficult terrain. The desert locust is the model for the presented bio-inspired design of a jumping mechanism for a small mobile robot. The basic mechanism is similar to that of the semilunar process in the hind legs of the locust, and is based on the cocking of a torsional spring by wrapping a tendon-like wire around the shaft of a miniature motor. In this study we present the jumping mechanism design, and the manufacturing and performance analysis of two demonstrator prototypes. The most advanced jumping robot demonstrator is power autonomous, weighs 23 gr, and is capable of jumping to a height of 3.35 m, covering a distance of 1.37 m.

  7. Body Size Evolution in Extant Oryzomyini Rodents: Cope's Rule or Miniaturization?

    PubMed Central

    Avaria-Llautureo, Jorge; Hernández, Cristián E.; Boric-Bargetto, Dusan; Canales-Aguirre, Cristian B.; Morales-Pallero, Bryan; Rodríguez-Serrano, Enrique

    2012-01-01

    At the macroevolutionary level, one of the first and most important hypotheses that proposes an evolutionary tendency in the evolution of body sizes is “Cope's rule". This rule has considerable empirical support in the fossil record and predicts that the size of species within a lineage increases over evolutionary time. Nevertheless, there is also a large amount of evidence indicating the opposite pattern of miniaturization over evolutionary time. A recent analysis using a single phylogenetic tree approach and a Bayesian based model of evolution found no evidence for Cope's rule in extant mammal species. Here we utilize a likelihood-based phylogenetic method, to test the evolutionary trend in body size, which considers phylogenetic uncertainty, to discern between Cope's rule and miniaturization, using extant Oryzomyini rodents as a study model. We evaluated body size trends using two principal predictions: (a) phylogenetically related species are more similar in their body size, than expected by chance; (b) body size increased (Cope's rule)/decreased (miniaturization) over time. Consequently the distribution of forces and/or constraints that affect the tendency are homogenous and generate this directional process from a small/large sized ancestor. Results showed that body size in the Oryzomyini tribe evolved according to phylogenetic relationships, with a positive trend, from a small sized ancestor. Our results support that the high diversity and specialization currently observed in the Oryzomyini tribe is a consequence of the evolutionary trend of increased body size, following and supporting Cope's rule. PMID:22509339

  8. MEMS technology to achieve miniaturization, redundancy, and new functionality in space

    NASA Astrophysics Data System (ADS)

    Grönland, Tor-Arne; Bendixen, Maria; Bejhed, Johan; Johansson, Håkan; Jonsson, Kerstin; Rangsten, Pelle

    2011-02-01

    Development of MEMS-based (Micro Electro Mechanical System) components and subsystems for space applications has been going on for at least two decades. The main driver for developing MEMS components for space is miniaturization through reduced mass, volume and power of individual components. However, the commercial breakthrough of MEMS has not occurred within the space business as it has within other branches such as the IT/telecom, the automotive industry, or other areas. In addition to miniaturization, increased redundancy and improved (or in some cases unique) performance has also been achieved by using MEMS-based components. MEMS pressure sensors integrated into the mechanical housing of another component is one example. Another example is an isolation valve which is both redundant and has an integrated particle filter on a single silicon chip weighing less than one gram. Currently there are few space missions using allowing newly developed MEMS devices onboard, but one of the exceptions is the Swedish-built Prisma satellites. One of the Prisma satellites has a MEMS-based cold gas propulsion system onboard, which contains a number of miniaturized and novel components. This paper presents the MEMS based cold gas propulsion system developed for Prisma including a number of novel components and their maiden spaceflight onboard Prisma last year.

  9. A Coupled Model for the Simulation of Miniaturized and Integrated Photoacoustic Gas Detector

    NASA Astrophysics Data System (ADS)

    Glière, A.; Rouxel, J.; Parvitte, B.; Boutami, S.; Zéninari, V.

    2013-11-01

    In photoacoustic (PA) spectroscopy, the signal is inversely proportional to the resonant cell volume. This favorable scaling behavior has provoked in recent years a growing interest in the miniaturization of PA cells. Due to dimension downscaling, technological constraints, and preliminary design choices, the modeling hypotheses used at the macro-scale are no longer valid. Here, a new model adapted to miniaturized and integrated PA (-PA) sensors is presented. The coupled model takes advantage of commercial software to address, respectively, (i) the electromagnetic mode propagation in the waveguide, (ii) the mid-IR light illumination of the chamber and its interaction with the molecules of interest, and (iii) the creation and propagation of acoustic waves in the cell. The model has been used to confirm the validity of the choice of the differential Helmholtz resonator principle and to provide a prototype -PA cell geometry. It is shown that, in spite of the specific issues inherent to miniaturization and integration, in particular, the strong divergence of the light beam and the crucial influence of viscothermal dissipation processes, the -PA sensor produces a pressure signal compatible with the next generation of resonant microphone technology. The model will be further improved when measurements performed on the prototype currently in fabrication are available.

  10. Nanobarcode gene expression monitoring system for potential miniaturized space applications

    NASA Astrophysics Data System (ADS)

    Ruan, Weiming; Eastman, P. Scott; Cooke, Patrick A.; Park, Jennifer S.; Chu, Julia S. F.; Gray, Joe W.; Li, Song; Chen, Fanqing Frank

    Manned mission to space has been threatened by various cosmos risks including radiation, mirogravity, vacuum, confinement, etc., which may cause genetic variations of astronauts and eventually lead to damages of their health. Thus, the development of small biomedical devices, which can monitor astronaut gene expression changes, is useful for future long-term space missions. Using magnetic microbeads packed with nanocrystal quantum dots at controlled ratios, we were able to generate highly multiplexed nanobarcodes, which can encode a flexible panel of genes. Also, by using a reporter quantum dot, this nanobarcode platform can monitor and quantify gene expression level with improved speed and sensitivity. As a comparison, we studied TGF-β1 induced transcription changes in human bone marrow mesenchymal stem cells with both the nanobarcode microbead system and the Affymetrix GeneChip ® HTA system, which is currently considered as the industrial standard. Though using only 1/20 of the sample RNA, the nanobarcode system showed sensitivity equivalent to Affymetrix GeneChip ® system. The coefficient of variation, dynamic range, and accuracy of the nanobarcodes measurement is equivalent to that of the GeneChip ® HTA system. Therefore, this newly invented nanobarcode microbead platform is thought to be sensitive, flexible, cost-effective and accurate in a level equivalent to the conventional methods. As an extension of the use of this new platform, spacecrafts may carry this miniaturized system as a diagnostic tool for the astronauts.

  11. A novel planar ion funnel design for miniature ion optics

    SciTech Connect

    Chaudhary, A.; Amerom, Friso H. W. van; Short, R. T.

    2014-10-01

    The novel planar ion funnel (PIF) design presented in this article emphasizes simple fabrication, assembly, and operation, making it amenable to extreme miniaturization. Simulations performed in SIMION 8.0 indicate that ion focusing can be achieved by using a gradient of electrostatic potentials on concentric metal rings in a plane. A prototype was fabricated on a 35 × 35 mm custom-designed printed circuit board (PCB) with a center hole for ions to pass through and a series of concentric circular metal rings of increasing diameter on the front side of the PCB. Metal vias on the PCB electrically connected each metal ring to a resistive potential divider that was soldered on the back of the PCB. The PIF was tested at 5.5 × 10⁻⁶ Torr in a vacuum test setup that was equipped with a broad-beam ion source on the front and a micro channel plate (MCP) ion detector on the back of the PIF. The ion current recorded on the MCP anode during testing indicated a 23× increase in the ion transmission through the PIF when electric potentials were applied to the rings. These preliminary results demonstrate the functionality of a 2D ion funnel design with a much smaller footprint and simpler driving electronics than conventional 3D ion funnels. Future directions to improve the design and a possible micromachining approach to fabrication are discussed in the conclusions.

  12. A novel planar ion funnel design for miniature ion optics.

    PubMed

    Chaudhary, A; van Amerom, Friso H W; Short, R T

    2014-10-01

    The novel planar ion funnel (PIF) design presented in this article emphasizes simple fabrication, assembly, and operation, making it amenable to extreme miniaturization. Simulations performed in SIMION 8.0 indicate that ion focusing can be achieved by using a gradient of electrostatic potentials on concentric metal rings in a plane. A prototype was fabricated on a 35 × 35 mm custom-designed printed circuit board (PCB) with a center hole for ions to pass through and a series of concentric circular metal rings of increasing diameter on the front side of the PCB. Metal vias on the PCB electrically connected each metal ring to a resistive potential divider that was soldered on the back of the PCB. The PIF was tested at 5.5 × 10(-6) Torr in a vacuum test setup that was equipped with a broad-beam ion source on the front and a micro channel plate (MCP) ion detector on the back of the PIF. The ion current recorded on the MCP anode during testing indicated a 23× increase in the ion transmission through the PIF when electric potentials were applied to the rings. These preliminary results demonstrate the functionality of a 2D ion funnel design with a much smaller footprint and simpler driving electronics than conventional 3D ion funnels. Future directions to improve the design and a possible micromachining approach to fabrication are discussed in the conclusions.

  13. A novel planar ion funnel design for miniature ion optics

    NASA Astrophysics Data System (ADS)

    Chaudhary, A.; van Amerom, Friso H. W.; Short, R. T.

    2014-10-01

    The novel planar ion funnel (PIF) design presented in this article emphasizes simple fabrication, assembly, and operation, making it amenable to extreme miniaturization. Simulations performed in SIMION 8.0 indicate that ion focusing can be achieved by using a gradient of electrostatic potentials on concentric metal rings in a plane. A prototype was fabricated on a 35 × 35 mm custom-designed printed circuit board (PCB) with a center hole for ions to pass through and a series of concentric circular metal rings of increasing diameter on the front side of the PCB. Metal vias on the PCB electrically connected each metal ring to a resistive potential divider that was soldered on the back of the PCB. The PIF was tested at 5.5 × 10-6 Torr in a vacuum test setup that was equipped with a broad-beam ion source on the front and a micro channel plate (MCP) ion detector on the back of the PIF. The ion current recorded on the MCP anode during testing indicated a 23× increase in the ion transmission through the PIF when electric potentials were applied to the rings. These preliminary results demonstrate the functionality of a 2D ion funnel design with a much smaller footprint and simpler driving electronics than conventional 3D ion funnels. Future directions to improve the design and a possible micromachining approach to fabrication are discussed in the conclusions.

  14. Miniature six-DOF inertial system for tracking HMDs

    NASA Astrophysics Data System (ADS)

    Foxlin, Eric M.; Harrington, Michael; Altshuler, Yury

    1998-08-01

    Current HMD applications are hampered by the limitations of head-tracking technologies now in use. Commercially available magnetic, optical, acoustic, and mechanical head- trackers suffer form various problems such as vulnerability to interference, line-of-sight restrictions, jitter, latency, small range, and high cost. This paper presents inertial-sensor-based hybrid tracking technology that was developed to combat all these problems. Two commercially available products, the IS-300 and the IS-600, are described, both based on the same miniature triaxial inertial sensor device. The IS-300 is a sourceless 3-DOF orientation tracker, using gravimetric tilt-sensing to prevent any gyroscopic drift in pitch and roll, and optical geo-magnetic compassing to prevent any gyroscopic drift in yaw. The IS-600 is a hybrid acousto-inertial 6-DOF position and orientation tracking system. It tracks changes in orientation and position by integrating the outputs of its gyros and accelerometers, and corrects drift using a room- referenced ultrasonic time-of-flight range measuring system. The is paper overviews the theory of operation of both systems, and reports bench-testing results designed to evaluate the resolution, accuracy, and latency of each system.

  15. All-Solid-State Conductive Polymer Miniaturized Reference Electrode

    NASA Astrophysics Data System (ADS)

    Chen, Chien Cheng; Chou, Jung Chuan

    2009-11-01

    A novel, stable, and all-solid-state miniaturized reference electrode (MRE) prepared by changing the properties of a conductive polymer for potentiometric applications is presented in this study. A monomer of a conductive polymer, pyrrole, was electrodeposited to form polypyrrole on an indium-tin oxide (ITO) glass at a DC power of 5 V. The difference of the solid-state MRE from the Ag/AgCl glass reference electrode is that the former requires no inner electrolyte and can be preserved without any storage solution (such as saturated KCl solution). In this study, the potentiometric characteristics of the solid-state MRE are investigated using the current-voltage (I-V) measurement system. The solid-state MRE exhibits sufficient stability and reproducibility in acid-base, sodium chloride, and potassium chloride solutions. Furthermore, the solid-state MRE can collocate successfully with H+-, Na+-, and K+-ion selective electrodes to measure H+, Na+, and K+ ion concentrations in acid-base, sodium chloride, and potassium chloride solutions, respectively.

  16. A miniaturized neuroprosthesis suitable for implantation into the brain

    NASA Technical Reports Server (NTRS)

    Mojarradi, Mohammad; Binkley, David; Blalock, Benjamin; Andersen, Richard; Ulshoefer, Norbert; Johnson, Travis; Del Castillo, Linda

    2003-01-01

    This paper presents current research on a miniaturized neuroprosthesis suitable for implantation into the brain. The prosthesis is a heterogeneous integration of a 100-element microelectromechanical system (MEMS) electrode array, front-end complementary metal-oxide-semiconductor (CMOS) integrated circuit for neural signal preamplification, filtering, multiplexing and analog-to-digital conversion, and a second CMOS integrated circuit for wireless transmission of neural data and conditioning of wireless power. The prosthesis is intended for applications where neural signals are processed and decoded to permit the control of artificial or paralyzed limbs. This research, if successful, will allow implantation of the electronics into the brain, or subcutaneously on the skull, and eliminate all external signal and power wiring. The neuroprosthetic system design has strict size and power constraints with each of the front-end preamplifier channels fitting within the 400 x 400-microm pitch of the 100-element MEMS electrode array and power dissipation resulting in less than a 1 degree C temperature rise for the surrounding brain tissue. We describe the measured performance of initial micropower low-noise CMOS preamplifiers for the neuroprosthetic.

  17. A miniature high resolution 3-D imaging sonar.

    PubMed

    Josserand, Tim; Wolley, Jason

    2011-04-01

    This paper discusses the design and development of a miniature, high resolution 3-D imaging sonar. The design utilizes frequency steered phased arrays (FSPA) technology. FSPAs present a small, low-power solution to the problem of underwater imaging sonars. The technology provides a method to build sonars with a large number of beams without the proportional power, circuitry and processing complexity. The design differs from previous methods in that the array elements are manufactured from a monolithic material. With this technique the arrays are flat and considerably smaller element dimensions are achievable which allows for higher frequency ranges and smaller array sizes. In the current frequency range, the demonstrated array has ultra high image resolution (1″ range×1° azimuth×1° elevation) and small size (<3″×3″). The design of the FSPA utilizes the phasing-induced frequency-dependent directionality of a linear phased array to produce multiple beams in a forward sector. The FSPA requires only two hardware channels per array and can be arranged in single and multiple array configurations that deliver wide sector 2-D images. 3-D images can be obtained by scanning the array in a direction perpendicular to the 2-D image field and applying suitable image processing to the multiple scanned 2-D images. This paper introduces the 3-D FSPA concept, theory and design methodology. Finally, results from a prototype array are presented and discussed.

  18. Miniaturized LED sources for in vivo optogenetic experimentation

    NASA Astrophysics Data System (ADS)

    Clements, Isaac P.; Gnade, Andrew G.; Rush, Alexander D.; Patten, Craig D.; Twomey, Mark C.; Kravitz, Alexxai V.

    2013-03-01

    Recently developed optogenetics techniques have enabled researchers to modulate the activity of specific cell types. As a result, complex neural pathways previously regarded as black boxes can now be directly probed, yielding a steadily increasing understanding of the basic neural circuits that underlie health and disease. For in vivo experimentation, fiber-coupled lasers have traditionally been used to illuminate internal brain regions, via an optical fiber that penetrates through overlying tissue. Though able to deliver intense fiber-coupled light, lasers are costly, bulky, and face limitations in output beam stability and temporal precision during modulated outputs. For experiments on unrestricted, behaving animals, a laser-based system also necessitates the use of fiber optic rotary joints, which come with costs and limitations of their own. Here, we report and characterize an alternative light delivery solution, based on high intensity fiber-coupled LEDs that are miniaturized for placement on the end of custom electrical commutators. This design allows for enhanced control of output light and expanded capabilities for optical stimulation as well as simultaneous electrical neural recordings, as with an optrode array. Temporal response of light outputs and light stability during commutator rotation were assessed. The influence of high current optical control signals on adjacent neural recording channels was also explored. To validate the function of this LED based system in in vivo recording scenarios, chronic stimulation experiments were performed.

  19. Miniaturized pulsed CO2 laser with sealed electron source

    NASA Astrophysics Data System (ADS)

    Bychkov, Y. I.; Orlovskiy, V. M.; Osipov, V. V.; Poteryayev, A. G.

    1984-04-01

    A new miniature electron beam-controlled CO2 laser (the MIG-3) contains an electron accelerator, gas cell and DC supply in one large unit (0.22 x 0,16 x 0.7 m) and the accelerator power supply and laser control panel in a second smaller unit. The overall weight of the instrument in 30 kg. The electron beam is controlled by four vacuum diodes in parallel; a 180 KV pulse is fed to the vacuum diode inputs from a "NORA" series-produced X-ray source (the MIRA-3D) also is used). The total electron beam current from all diodes was 600 A following the foil with a half-height width of 10 ns. The lasing medium is CO2:N2 - 1:1 at 4.5 atm. The maximum stimulated emission pulse energy was 1 J with an efficiency of 8% when the pressure was 4 atm. With a pulse repetition rate of 4 Hz, the average power consumption of the unit was 100 W.

  20. Production of transgenic miniature pigs by pronuclear microinjection.

    PubMed

    Uchida, M; Shimatsu, Y; Onoe, K; Matsuyama, N; Niki, R; Ikeda, J E; Imai, H

    2001-12-01

    Miniature pig is an attractive animal for a wide range of research fields, such as medicine and pharmacology, because of its small size, the possibility of breeding it under minimum environmental controls and the physiology that is potentially similar to that of human. Although transgenic technology is useful for the analysis of gene function and for the development of model animals for various diseases, there have not yet been any reports on producing transgenic miniature pig. This study is the first successful report concerning the production of transgenic miniature pig by pronuclear microinjection. The huntingtin gene cloned from miniature pig, which is a homologue of candidate gene for Huntington's disease, connected with rat neuron-specific enolase promoter region, was injected into a pronucleus of fertilized eggs with micromanipulator. The eggs were transferred into the oviduct of recipient miniature pigs, whose estrus cycles were previously synchronized with a progesterone analogue. A total of 402 injected eggs from 171 donors were transferred to 23 synchronized recipients. Sixteen of them maintained pregnancy and delivered 65 young, and one resulted in abortion. Five of the 68 offspring (three of which were aborted) were determined to have transgene by PCR and Southern analysis. The overall rate of transgenic production was 1.24% (transgenic/injected eggs). This study provides the first success and useful information regarding production of transgenic miniature pig for biomedical research.