WorldWideScience

Sample records for nano brain operating

  1. Operation Brain Trauma Therapy

    Science.gov (United States)

    2016-12-01

    Ho, C., Jenkins, L.W., and Kochanek, P.M. (2013). MRI assessment of cerebral blood flow following experimental traumatic brain injury combined with...Neuroproteomics and Biomarkers Research, Banyan Biomarkers, Inc., Alachua, Florida. 8Center for Pharmaceutical Sciences, University of Pittsburgh School... Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania. 8Center for Innovative Research, Center for Neuroproteomics and

  2. Operation Brain Trauma Therapy

    Science.gov (United States)

    2014-10-01

    some samples double labeled for 3D reconstruction of the obtained confocal images. Although these studies are not fully complete, a detailed...traumatic brain injury in adult rats. Exp Neurol. 2010;224:241-251. 43. Turkoglu OF, Eroglu H, Gurcan O, et al. Local administration of chitosan

  3. Brain performance enhancement for military operators

    NARCIS (Netherlands)

    Erp, J.B.F.; Reschke, S.; Grootjen, M.; Brouwer, A.-M.

    2009-01-01

    Performance of military operators depends on both physical and cognitive aspects. Enhancement of operator performance should therefore address both the body and the brain. This paper focuses on the latter. We provide an extended list of areas where neuroscientific knowledge may be important like

  4. Fabrication and Operation of a Nano-Optical Conveyor Belt.

    Science.gov (United States)

    Ryan, Jason; Zheng, Yuxin; Hansen, Paul; Hesselink, Lambertus

    2015-08-26

    The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological and physical sciences over the past few decades. The progress made in this field invites further study of even smaller systems and at a larger scale, with tools that could be distributed more easily and made more widely available. Unfortunately, the fundamental laws of diffraction limit the minimum size of the focal spot of a laser beam, which makes particles smaller than a half-wavelength in diameter hard to trap and generally prevents an operator from discriminating between particles which are closer together than one half-wavelength. This precludes the optical manipulation of many closely-spaced nanoparticles and limits the resolution of optical-mechanical systems. Furthermore, manipulation using focused beams requires beam-forming or steering optics, which can be very bulky and expensive. To address these limitations in the system scalability of conventional optical trapping our lab has devised an alternative technique which utilizes near-field optics to move particles across a chip. Instead of focusing laser beams in the far-field, the optical near field of plasmonic resonators produces the necessary local optical intensity enhancement to overcome the restrictions of diffraction and manipulate particles at higher resolution. Closely-spaced resonators produce strong optical traps which can be addressed to mediate the hand-off of particles from one to the next in a conveyor-belt-like fashion. Here, we describe how to design and produce a conveyor belt using a gold surface patterned with plasmonic C-shaped resonators and how to operate it with polarized laser light to achieve super-resolution nanoparticle manipulation and transport. The nano-optical conveyor belt chip can be produced using lithography techniques and easily packaged and distributed.

  5. Micro- and nano-technologies to probe the mechano-biology of the brain.

    Science.gov (United States)

    Tay, Andy; Schweizer, Felix E; Di Carlo, Dino

    2016-05-24

    Biomechanical forces have been demonstrated to influence a plethora of neuronal functions across scales including gene expression, mechano-sensitive ion channels, neurite outgrowth and folding of the cortices in the brain. However, the detailed roles biomechanical forces may play in brain development and disorders has seen limited study, partly due to a lack of effective methods to probe the mechano-biology of the brain. Current techniques to apply biomechanical forces on neurons often suffer from low throughput and poor spatiotemporal resolution. On the other hand, newly developed micro- and nano-technologies can overcome these aforementioned limitations and offer advantages such as lower cost and possibility of non-invasive control of neuronal circuits. This review compares the range of conventional, micro- and nano-technological techniques that have been developed and how they have been or can be used to understand the effect of biomechanical forces on neuronal development and homeostasis.

  6. Nano-Modeling and Computation in Bio and Brain Dynamics

    Directory of Open Access Journals (Sweden)

    Paolo Di Sia

    2016-04-01

    Full Text Available The study of brain dynamics currently utilizes the new features of nanobiotechnology and bioengineering. New geometric and analytical approaches appear very promising in all scientific areas, particularly in the study of brain processes. Efforts to engage in deep comprehension lead to a change in the inner brain parameters, in order to mimic the external transformation by the proper use of sensors and effectors. This paper highlights some crossing research areas of natural computing, nanotechnology, and brain modeling and considers two interesting theoretical approaches related to brain dynamics: (a the memory in neural network, not as a passive element for storing information, but integrated in the neural parameters as synaptic conductances; and (b a new transport model based on analytical expressions of the most important transport parameters, which works from sub-pico-level to macro-level, able both to understand existing data and to give new predictions. Complex biological systems are highly dependent on the context, which suggests a “more nature-oriented” computational philosophy.

  7. Nano

    DEFF Research Database (Denmark)

    Nørgaard, Bent; Engel, Lars Romann

    2007-01-01

    Gennem de sidste par år har et lille ord med et meget stort potentiale gentagende trængt sig på i den offentlige bevidsthed, det er ordet "nano". Nanovidenskab og nanoteknologi er lige nu to af de "hotteste" forskningsområder og betragtes af mange som porten til en helt ny verden af muligheder....... Muligheder, vi endnu ikke kender konsekvenserne af. Center for Kunst og Videnskabs forestilling NANO giver dig chancen for at blive bekendt med verdens mindste byggesten og idégrundlaget for nanoforskningen. Vi har skabt et rum, som på mange måder minder om et laboratorium. Rummet er forsynet med storskærme......, kolber, væsker og nanopartikler. Her vil du f.eks. opleve, hvordan forskere tilfører guld helt nye egenskaber. Forestillingen veksler mellem kemiske arbejdsdemonstrationer, stemningsskabende musik og livlig debat på storskærme mellem eksperter. NANO opfordrer publikum til at tage stilling til forskningen...

  8. Nano carriers for drug transport across the blood-brain barrier.

    Science.gov (United States)

    Li, Xinming; Tsibouklis, John; Weng, Tingting; Zhang, Buning; Yin, Guoqiang; Feng, Guangzhu; Cui, Yingde; Savina, Irina N; Mikhalovska, Lyuba I; Sandeman, Susan R; Howel, Carol A; Mikhalovsky, Sergey V

    2017-01-01

    Effective therapy lies in achieving a therapeutic amount of drug to the proper site in the body and then maintaining the desired drug concentration for a sufficient time interval to be clinically effective for treatment. The blood-brain barrier (BBB) hinders most drugs from entering the central nervous system (CNS) from the blood stream, leading to the difficulty of delivering drugs to the brain via the circulatory system for the treatment, diagnosis and prevention of brain diseases. Several brain drug delivery approaches have been developed, such as intracerebral and intracerebroventricular administration, intranasal delivery and blood-to-brain delivery, as a result of transient BBB disruption induced by biological, chemical or physical stimuli such as zonula occludens toxin, mannitol, magnetic heating and ultrasound, but these approaches showed disadvantages of being dangerous, high cost and unsuitability for most brain diseases and drugs. The strategy of vector-mediated blood-to-brain delivery, which involves improving BBB permeability of the drug-carrier conjugate, can minimize side effects, such as being submicrometre objects that behave as a whole unit in terms of their transport and properties, nanomaterials, are promising carrier vehicles for direct drug transport across the intact BBB as a result of their potential to enter the brain capillary endothelial cells by means of normal endocytosis and transcytosis due to their small size, as well as their possibility of being functionalized with multiple copies of the drug molecule of interest. This review provids a concise discussion of nano carriers for drug transport across the intact BBB, various forms of nanomaterials including inorganic/solid lipid/polymeric nanoparticles, nanoemulsions, quantum dots, nanogels, liposomes, micelles, dendrimers, polymersomes and exosomes are critically evaluated, their mechanisms for drug transport across the BBB are reviewed, and the future directions of this area are fully

  9. Combinatorial control of messenger RNAs by Pumilio, Nanos and Brain Tumor Proteins.

    Science.gov (United States)

    Arvola, René M; Weidmann, Chase A; Tanaka Hall, Traci M; Goldstrohm, Aaron C

    2017-11-02

    Eukaryotes possess a vast array of RNA-binding proteins (RBPs) that affect mRNAs in diverse ways to control protein expression. Combinatorial regulation of mRNAs by RBPs is emerging as the rule. No example illustrates this as vividly as the partnership of 3 Drosophila RBPs, Pumilio, Nanos and Brain Tumor, which have overlapping functions in development, stem cell maintenance and differentiation, fertility and neurologic processes. Here we synthesize 30 y of research with new insights into their molecular functions and mechanisms of action. First, we provide an overview of the key properties of each RBP. Next, we present a detailed analysis of their collaborative regulatory mechanism using a classic example of the developmental morphogen, hunchback, which is spatially and temporally regulated by the trio during embryogenesis. New biochemical, structural and functional analyses provide insights into RNA recognition, cooperativity, and regulatory mechanisms. We integrate these data into a model of combinatorial RNA binding and regulation of translation and mRNA decay. We then use this information, transcriptome wide analyses and bioinformatics predictions to assess the global impact of Pumilio, Nanos and Brain Tumor on gene regulation. Together, the results support pervasive, dynamic post-transcriptional control.

  10. Development of Nb nanoSQUIDs based on SNS junctions for operation in high magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Morosh, Viacheslav; Kieler, Oliver; Weimann, Thomas; Zorin, Alexander [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany); Mueller, Benedikt; Martinez-Perez, Maria Jose; Kleiner, Reinhold; Koelle, Dieter [Physikalisches Institut and Center for Quantum Science in LISA+, Universitaet Tuebingen (Germany)

    2016-07-01

    Investigation of the magnetization reversal of single magnetic nanoparticles requires SQUIDs with high spatial resolution, high spin sensitivity (a few Bohr magneton μ{sub B}) and at the same time sufficient stability in high magnetic fields. We fabricated dc nanoSQUIDs comprising overdamped SNS sandwich-type (Nb/HfTi/Nb) Josephson junctions using optimized technology based on combination of electron beam lithography and chemical-mechanical polishing. Our nanoSQUIDs have Josephson junctions with lateral dimensions ≤ 150 nm x 150 nm, effective loop areas < 0.05 μm{sup 2} and the distance between the Josephson junctions ≤ 100 nm. The feeding strip lines of the width ≤ 200 nm have been realized. The nanoSQUIDs have shown stable operation in external magnetic fields at least up to 250 mT. Sufficiently low level of flux noise resulting in spin sensitivity of few tens μ{sub B}/Hz{sup 1/2} has been demonstrated. A further reduction of the nanoSQUID size using our technology is possible.

  11. Analyzing collaboration networks and developmental patterns of nano-enabled drug delivery (NEDD for brain cancer

    Directory of Open Access Journals (Sweden)

    Ying Huang

    2015-07-01

    Full Text Available The rapid development of new and emerging science & technologies (NESTs brings unprecedented challenges, but also opportunities. In this paper, we use bibliometric and social network analyses, at country, institution, and individual levels, to explore the patterns of scientific networking for a key nano area – nano-enabled drug delivery (NEDD. NEDD has successfully been used clinically to modulate drug release and to target particular diseased tissues. The data for this research come from a global compilation of research publication information on NEDD directed at brain cancer. We derive a family of indicators that address multiple facets of research collaboration and knowledge transfer patterns. Results show that: (1 international cooperation is increasing, but networking characteristics change over time; (2 highly productive institutions also lead in influence, as measured by citation to their work, with American institutes leading; (3 research collaboration is dominated by local relationships, with interesting information available from authorship patterns that go well beyond journal impact factors. Results offer useful technical intelligence to help researchers identify potential collaborators and to help inform R&D management and science & innovation policy for such nanotechnologies.

  12. Brain computer interface for operating a robot

    Science.gov (United States)

    Nisar, Humaira; Balasubramaniam, Hari Chand; Malik, Aamir Saeed

    2013-10-01

    A Brain-Computer Interface (BCI) is a hardware/software based system that translates the Electroencephalogram (EEG) signals produced by the brain activity to control computers and other external devices. In this paper, we will present a non-invasive BCI system that reads the EEG signals from a trained brain activity using a neuro-signal acquisition headset and translates it into computer readable form; to control the motion of a robot. The robot performs the actions that are instructed to it in real time. We have used the cognitive states like Push, Pull to control the motion of the robot. The sensitivity and specificity of the system is above 90 percent. Subjective results show a mixed trend of the difficulty level of the training activities. The quantitative EEG data analysis complements the subjective results. This technology may become very useful for the rehabilitation of disabled and elderly people.

  13. Highly Efficient Spin-Current Operation in a Cu Nano-Ring

    Science.gov (United States)

    Murphy, Benedict A.; Vick, Andrew J.; Samiepour, Marjan; Hirohata, Atsufumi

    2016-11-01

    An all-metal lateral spin-valve structure has been fabricated with a medial Copper nano-ring to split the diffusive spin-current path. We have demonstrated significant modulation of the non-local signal by the application of a magnetic field gradient across the nano-ring, which is up to 30% more efficient than the conventional Hanle configuration at room temperature. This was achieved by passing a dc current through a current-carrying bar to provide a locally induced Ampère field. We have shown that in this manner a lateral spin-valve gains an additional functionality in the form of three-terminal gate operation for future spintronic logic.

  14. Drosophila Pumilio protein contains multiple autonomous repression domains that regulate mRNAs independently of Nanos and brain tumor.

    Science.gov (United States)

    Weidmann, Chase A; Goldstrohm, Aaron C

    2012-01-01

    Drosophila melanogaster Pumilio is an RNA-binding protein that potently represses specific mRNAs. In developing embryos, Pumilio regulates a key morphogen, Hunchback, in collaboration with the cofactor Nanos. To investigate repression by Pumilio and Nanos, we created cell-based assays and found that Pumilio inhibits translation and enhances mRNA decay independent of Nanos. Nanos robustly stimulates repression through interactions with the Pumilio RNA-binding domain. We programmed Pumilio to recognize a new binding site, which garners repression of new target mRNAs. We show that cofactors Brain Tumor and eIF4E Homologous Protein are not obligatory for Pumilio and Nanos activity. The conserved RNA-binding domain of Pumilio was thought to be sufficient for its function. Instead, we demonstrate that three unique domains in the N terminus of Pumilio possess the major repressive activity and can function autonomously. The N termini of insect and vertebrate Pumilio and Fem-3 binding factors (PUFs) are related, and we show that corresponding regions of human PUM1 and PUM2 have repressive activity. Other PUF proteins lack these repression domains. Our findings suggest that PUF proteins have evolved new regulatory functions through protein sequences appended to their conserved PUF repeat RNA-binding domains.

  15. Application of exergetic sustainability index to a nano-scale irreversible Brayton cycle operating with ideal Bose and Fermi gasses

    Energy Technology Data Exchange (ETDEWEB)

    Açıkkalp, Emin, E-mail: eacikkalp@gmail.com [Department of Mechanical and Manufacturing Engineering, Engineering Faculty, Bilecik S.E. University, Bilecik (Turkey); Caner, Necmettin [Department of Chemistry, Faculty of Arts and Sciences, Eskisehir Osmangazi University, Eskisehir (Turkey)

    2015-09-25

    Highlights: • An irreversible Brayton cycle operating quantum gasses is considered. • Exergetic sustainability index is derived for nano-scale cycles. • Nano-scale effects are considered. • Calculation are conducted for irreversible cycles. • Numerical results are presented and discussed. - Abstract: In this study, a nano-scale irreversible Brayton cycle operating with quantum gasses including Bose and Fermi gasses is researched. Developments in the nano-technology cause searching the nano-scale machines including thermal systems to be unavoidable. Thermodynamic analysis of a nano-scale irreversible Brayton cycle operating with Bose and Fermi gasses was performed (especially using exergetic sustainability index). In addition, thermodynamic analysis involving classical evaluation parameters such as work output, exergy output, entropy generation, energy and exergy efficiencies were conducted. Results are submitted numerically and finally some useful recommendations were conducted. Some important results are: entropy generation and exergetic sustainability index are affected mostly for Bose gas and power output and exergy output are affected mostly for the Fermi gas by x. At the high temperature conditions, work output and entropy generation have high values comparing with other degeneracy conditions.

  16. Effect of operating microscope light on brain temperature during craniotomy.

    Science.gov (United States)

    Gayatri, Parthasarathi; Menon, Girish G; Suneel, Puthuvassery R

    2013-07-01

    Operating microscopes used during neurosurgery are fitted with xenon light. Burn injuries have been reported because of xenon microscope lighting as the intensity of xenon light is 300 W. We designed this study to find out if the light of operating microscope causes an increase in temperature of the brain tissue, which is exposed underneath. Twenty-one adult patients scheduled for elective craniotomies were enrolled. Distal esophageal temperature (T Eso), brain temperature under the microscope light (T Brain), and brain temperature under dura mater (T Dura) were measured continuously at 15-minute intervals during microscope use. The irrigation fluid temperature, room temperature, intensity of the microscope light, and the distance of the microscope from the brain surface were kept constant. The average age of the patients was 44±15 years (18 males and 3 females). The mean duration of microscope use was 140±39 minutes. There were no significant changes in T Brain and T Dura and T Eso over time. T Dura was significantly lower than T Brain both at time 0 and 60 minutes but not at 90 minutes. T Brain was significantly lower than T Eso both at time 0 and 60 minutes but not at 90 minutes. The T Dura remained significantly lower than T Eso at 0, 60, and 90 minutes. Our study shows that there is no significant rise in brain temperature under xenon microscope light up to 120 minutes duration, at intensity of 60% to 70%, from a distance of 20 to 25 cm from the brain surface.

  17. REAL TIME MEASUREMENT OF ULTRAFINE AND NANO PARTICLES AND SIGNIFICANCE OF OPERATING GEARS

    Directory of Open Access Journals (Sweden)

    H. A. NAKHAWA

    2017-03-01

    Full Text Available This research paper focuses on characterization of ultrafine and nanoparticle emissions from diesel vehicle to investigate their physical characterization in terms of number and size as they are more vulnerable and responsible for toxicity, mutagenicity and carcinogenicity. An investigation has been carried out to identify the significance of different operating gears, clutch, declutch and gear change operations for their contributions to particle number(PN on urban and extra urban part of the driving cycle. A bi-modal particle size distribution pattern was observed for both urban and extra urban parts where almost all the particles are below 200 nm and particle number peaks appear at 7 to 8 nm and at 70 nm. Nano particles contribute approximately, 70% of total particle number over urban part. Experimental investigation shows that the most significant gear for their contribution to particle number are 3rd and 5th gears on urban and extra urban part of the driving cycle respectively.

  18. Research for correction pre-operative MRI images of brain during operation using particle method simulation

    International Nuclear Information System (INIS)

    Shino, Ryosaku; Koshizuka, Seiichi; Sakai, Mikio; Ito, Hirotaka; Iseki, Hiroshi; Muragaki, Yoshihiro

    2010-01-01

    In the neurosurgical procedures, surgeon formulates a surgery plan based on pre-operative images such as MRI. However, the brain is transformed by removal of the affected area. In this paper, we propose a method for reconstructing pre-operative images involving the deformation with physical simulation. First, the domain of brain is identified in pre-operative images. Second, we create particles for physical simulation. Then, we carry out the linear elastic simulation taking into account the gravity. Finally, we reconstruct pre-operative images with deformation according to movement of the particles. We show the effectiveness of this method by reconstructing the pre-operative image actually taken before surgery. (author)

  19. Connectome analysis for pre-operative brain mapping in neurosurgery

    Science.gov (United States)

    Hart, Michael G.; Price, Stephen J.; Suckling, John

    2016-01-01

    Abstract Object: Brain mapping has entered a new era focusing on complex network connectivity. Central to this is the search for the connectome or the brains ‘wiring diagram’. Graph theory analysis of the connectome allows understanding of the importance of regions to network function, and the consequences of their impairment or excision. Our goal was to apply connectome analysis in patients with brain tumours to characterise overall network topology and individual patterns of connectivity alterations. Methods: Resting-state functional MRI data were acquired using multi-echo, echo planar imaging pre-operatively from five participants each with a right temporal–parietal–occipital glioblastoma. Complex networks analysis was initiated by parcellating the brain into anatomically regions amongst which connections were identified by retaining the most significant correlations between the respective wavelet decomposed time-series. Results: Key characteristics of complex networks described in healthy controls were preserved in these patients, including ubiquitous small world organization. An exponentially truncated power law fit to the degree distribution predicted findings of general network robustness to injury but with a core of hubs exhibiting disproportionate vulnerability. Tumours produced a consistent reduction in local and long-range connectivity with distinct patterns of connection loss depending on lesion location. Conclusions: Connectome analysis is a feasible and novel approach to brain mapping in individual patients with brain tumours. Applications to pre-surgical planning include identifying regions critical to network function that should be preserved and visualising connections at risk from tumour resection. In the future one could use such data to model functional plasticity and recovery of cognitive deficits. PMID:27447756

  20. Connectome analysis for pre-operative brain mapping in neurosurgery.

    Science.gov (United States)

    Hart, Michael G; Price, Stephen J; Suckling, John

    2016-10-01

    Brain mapping has entered a new era focusing on complex network connectivity. Central to this is the search for the connectome or the brains 'wiring diagram'. Graph theory analysis of the connectome allows understanding of the importance of regions to network function, and the consequences of their impairment or excision. Our goal was to apply connectome analysis in patients with brain tumours to characterise overall network topology and individual patterns of connectivity alterations. Resting-state functional MRI data were acquired using multi-echo, echo planar imaging pre-operatively from five participants each with a right temporal-parietal-occipital glioblastoma. Complex networks analysis was initiated by parcellating the brain into anatomically regions amongst which connections were identified by retaining the most significant correlations between the respective wavelet decomposed time-series. Key characteristics of complex networks described in healthy controls were preserved in these patients, including ubiquitous small world organization. An exponentially truncated power law fit to the degree distribution predicted findings of general network robustness to injury but with a core of hubs exhibiting disproportionate vulnerability. Tumours produced a consistent reduction in local and long-range connectivity with distinct patterns of connection loss depending on lesion location. Connectome analysis is a feasible and novel approach to brain mapping in individual patients with brain tumours. Applications to pre-surgical planning include identifying regions critical to network function that should be preserved and visualising connections at risk from tumour resection. In the future one could use such data to model functional plasticity and recovery of cognitive deficits.

  1. Brain Targeted Intranasal Zaleplon Nano-emulsion: In-Vitro Characterization and Assessment of Gamma Aminobutyric Acid Levels in rabbits' Brain and Plasma at low and high Doses.

    Science.gov (United States)

    Abd-Elrasheed, Eman; El-Helaly, Sara Nageeb; El-Ashmoony, Manal M; Salah, Salwa

    2017-11-30

    Zaleplon is a pyrazolopyrimidin derivative hypnotic drug indicated for the short-term management of insomnia. Zaleplon belongs to Class II drugs, according to the biopharmaceutical classification system (BCS), showing poor solubility and high permeability. It undergoes extensive first-pass hepatic metabolism after oral absorption, with only 30% of Zaleplon being systemically available. It is available in tablet form which is unable to overcome the previous problems. The aim of this study is to enhance solubility and bioavailability via utilizing nanotechnology in the formulation of intranasal Zaleplon nano-emulsion (ZP-NE) to bypass the barriers and deliver an effective therapy to the brain. Screening studies were carried out wherein the solubility of zaleplon in various oils, surfactants(S) and co-surfactants(CoS) were estimated. Pseudo-ternary phase diagrams were constructed and various nano-emulsion formulations were prepared. These formulations were subjected to thermodynamic stability, in-vitro characterization, histopathological studies and assessment of the gamma aminobutyric acid (GABA) level in plasma and brain in rabbits compared to the market product (Sleep aid®). Stable NEs were successfully developed with a particle size range of 44.57±3.351 to 136.90±1.62 nm. A NE composed of 10% Miglyol® 812, 40%Cremophor® RH40 40%Transcutol® HP and 10% water successfully enhanced the bioavailability and brain targeting in the rabbits, showing a three to four folds increase than the marketed product. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Potential predictors for the amount of intra-operative brain shift during deep brain stimulation surgery

    Science.gov (United States)

    Datteri, Ryan; Pallavaram, Srivatsan; Konrad, Peter E.; Neimat, Joseph S.; D'Haese, Pierre-François; Dawant, Benoit M.

    2011-03-01

    A number of groups have reported on the occurrence of intra-operative brain shift during deep brain stimulation (DBS) surgery. This has a number of implications for the procedure including an increased chance of intra-cranial bleeding and complications due to the need for more exploratory electrodes to account for the brain shift. It has been reported that the amount of pneumocephalus or air invasion into the cranial cavity due to the opening of the dura correlates with intraoperative brain shift. Therefore, pre-operatively predicting the amount of pneumocephalus expected during surgery is of interest toward accounting for brain shift. In this study, we used 64 DBS patients who received bilateral electrode implantations and had a post-operative CT scan acquired immediately after surgery (CT-PI). For each patient, the volumes of the pneumocephalus, left ventricle, right ventricle, third ventricle, white matter, grey matter, and cerebral spinal fluid were calculated. The pneumocephalus was calculated from the CT-PI utilizing a region growing technique that was initialized with an atlas-based image registration method. A multi-atlas-based image segmentation method was used to segment out the ventricles of each patient. The Statistical Parametric Mapping (SPM) software package was utilized to calculate the volumes of the cerebral spinal fluid (CSF), white matter and grey matter. The volume of individual structures had a moderate correlation with pneumocephalus. Utilizing a multi-linear regression between the volume of the pneumocephalus and the statistically relevant individual structures a Pearson's coefficient of r = 0.4123 (p = 0.0103) was found. This study shows preliminary results that could be used to develop a method to predict the amount of pneumocephalus ahead of the surgery.

  3. Investigation of mechanical properties and operative deformation mechanism in nano-crystalline Ni–Co/SiC electrodeposits

    International Nuclear Information System (INIS)

    Lari Baghal, S.M.; Amadeh, A.; Heydarzadeh Sohi, M.

    2012-01-01

    Highlights: ► The tensile properties of Ni–Co and Ni–Co/SiC deposits were investigated. ► The SiC particles enhanced tensile strength and ductility of nano-structured composites. ► The deformation mechanism at low and high strain rates were studied. - Abstract: Ni–Co/SiC nano-composites were prepared via electrodeposition from a modified Watts bath containing SiC particles with average particle size of 50 nm, SDS as surfactant and saccharin as grain refiner in appropriate amounts. The effect of nano-particle incorporation on microstructure, mechanical properties and deformation mechanism of electrodeposits were investigated. The mechanical properties of electrodeposits were investigated by Vickers microhardness and tensile tests. The results indicated that incorporation of SiC particles into a 15 nm Ni–Co matrix had no considerable effect on its microhardness and yield strength, that is, dispersion hardening did not operate in this range of grain size. However it was observed that co-deposition of uniform distributed SiC particles can significantly improve the ultimate tensile strength and elongation to failure of the deposits. Calculation of apparent activation volume from tensile test results at different strain rates proved that incorporation of SiC nano-particles are responsible for stress-assisted activation of GB atoms mechanism that can significantly increase the plasticity. Nano-crystalline Ni–Co matrix showed a mixed mod behavior of ductile and brittle fracture whereas incorporation of SiC particles and increasing the strain rate promoted ductile fracture mode.

  4. Unsupervised classification of operator workload from brain signals

    Science.gov (United States)

    Schultze-Kraft, Matthias; Dähne, Sven; Gugler, Manfred; Curio, Gabriel; Blankertz, Benjamin

    2016-06-01

    Objective. In this study we aimed for the classification of operator workload as it is expected in many real-life workplace environments. We explored brain-signal based workload predictors that differ with respect to the level of label information required for training, including entirely unsupervised approaches. Approach. Subjects executed a task on a touch screen that required continuous effort of visual and motor processing with alternating difficulty. We first employed classical approaches for workload state classification that operate on the sensor space of EEG and compared those to the performance of three state-of-the-art spatial filtering methods: common spatial patterns (CSPs) analysis, which requires binary label information; source power co-modulation (SPoC) analysis, which uses the subjects’ error rate as a target function; and canonical SPoC (cSPoC) analysis, which solely makes use of cross-frequency power correlations induced by different states of workload and thus represents an unsupervised approach. Finally, we investigated the effects of fusing brain signals and peripheral physiological measures (PPMs) and examined the added value for improving classification performance. Main results. Mean classification accuracies of 94%, 92% and 82% were achieved with CSP, SPoC, cSPoC, respectively. These methods outperformed the approaches that did not use spatial filtering and they extracted physiologically plausible components. The performance of the unsupervised cSPoC is significantly increased by augmenting it with PPM features. Significance. Our analyses ensured that the signal sources used for classification were of cortical origin and not contaminated with artifacts. Our findings show that workload states can be successfully differentiated from brain signals, even when less and less information from the experimental paradigm is used, thus paving the way for real-world applications in which label information may be noisy or entirely unavailable.

  5. Intra-operative probe for brain cancer: feasibility study

    Science.gov (United States)

    Vu Thi, M. H.; Charon, Y.; Duval, M. A.; Lefebvre, F.; Menard, L.; Pitre, S.; Pinot, L.; Siebert, R.

    2007-07-01

    The present work aims a new medical probe for surgeons devoted to brain cancers, in particular glioblastoma multiforme. Within the last years, our group has started the development of a new intra-operative beta imaging probe. More recently, we took an alternative approach for the same application: a fluorescence probe. In both cases the purpose is to differentiate normal from tumor brain tissue. In a first step, we developed set-ups capable to measure autofluorescence. They are based on a dedicated epi-fluorescence design and on specific fiber optic probes. Relative signal amplitude, spectral shape and fluorescence lifetime measurements are foreseen to distinguish normal and cancer tissue by analyzing fluorophores like NADH, lipopigments and porphyrines. The autofluorescence spectra are recorded in the 460-640 nm range with a low resolution spectrometer. For lifetime measurements a fast detector (APD) is used together with a TCSPC-carte. Intrinsic wavelength- and time-resolutions are a few nm and 200 ps, respectively. Different samples have been analyzed to validate our new detection system and to allow a first configuration of our medical fluorescence probe. First results from the tissue measurements are shown.

  6. Intraperitoneal Exposure to Nano/Microparticles of Fullerene (C60) Increases Acetylcholinesterase Activity and Lipid Peroxidation in Adult Zebrafish (Danio rerio) Brain

    Science.gov (United States)

    Dal Forno, Gonzalo Ogliari; Kist, Luiza Wilges; de Azevedo, Mariana Barbieri; Fritsch, Rachel Seemann; Pereira, Talita Carneiro Brandão; Britto, Roberta Socoowski; Guterres, Sílvia Stanisçuaski; Külkamp-Guerreiro, Irene Clemes; Bonan, Carla Denise; Monserrat, José María; Bogo, Maurício Reis

    2013-01-01

    Even though technologies involving nano/microparticles have great potential, it is crucial to determine possible toxicity of these technological products before extensive use. Fullerenes C60 are nanomaterials with unique physicochemical and biological properties that are important for the development of many technological applications. The aim of this study was to evaluate the consequences of nonphotoexcited fullerene C60 exposure in brain acetylcholinesterase expression and activity, antioxidant responses, and oxidative damage using adult zebrafish as an animal model. None of the doses tested (7.5, 15, and 30 mg/kg) altered AChE activity, antioxidant responses, and oxidative damage when zebrafish were exposed to nonphotoexcited C60 nano/microparticles during 6 and 12 hours. However, adult zebrafish exposed to the 30 mg/kg dose for 24 hours have shown enhanced AChE activity and augmented lipid peroxidation (TBARS assays) in brain. In addition, the up-regulation of brain AChE activity was neither related to the transcriptional control (RT-qPCR analysis) nor to the direct action of nonphotoexcited C60 nano/microparticles on the protein (in vitro results) but probably involved a posttranscriptional or posttranslational modulation of this enzymatic activity. Taken together these findings provided further evidence of toxic effects on brain after C60 exposure. PMID:23865059

  7. Study of the performances of nano-case treatment cutting tools on carbon steel work material during turning operation

    Science.gov (United States)

    Afolalu, S. A.; Okokpujie, I. P.; Salawu, E. Y.; Abioye, A. A.; Abioye, O. P.; Ikumapayi, O. M.

    2018-04-01

    The degree of holding temperature and time play a major role in nano-case treatment of cutting tools which immensely contributed to its performance during machining operation. The objective of this research work is to carryout comparative study of performance of nano-case treatment tools developed using low and medium carbon steel as work piece. Turning operation was carried out under two different categories with specific work piece on universal lathe machine using HSS cutting tools 100 mm × 12mm × 12mm that has been nano-case treated under varying conditions of temperatures and timeof 800,850, 900, 950°C and 60, 90, 120 mins respectively. The turning parameters used in evaluating this experiment were cutting speed of 270, 380 and 560mm/min, feed rate of 0.15, 0.20 and 0.25 mm/min, depth of cut of 2mm, work piece diameter of 25mm and rake angle of 7° each at three levels. The results of comparative study of their performances revealed that the timespent in the machining of low carbon steel material at a minimum temperature and time of 800°C, 60 mins were1.50, 2.17 mins while at maximum temperature and time of 950°C, 120 mins were 1.19, 2.02 mins. It was also observed that at a corresponding constant speed of 270,380 and 560mm/min at higher temperature and time, a relative increased in the length of cut were observed. Critical observation of the result showed that at higher case hardening temperature and time (950°C/120mins), the HSS cutting tool gave a better performance as lesser time was consumed during the turning operation.

  8. Nano Materials

    International Nuclear Information System (INIS)

    Jin, In Ju; Lee, Ik Mo; Kwon, Yeung Gu

    2006-02-01

    This book introduces background of nano science such as summary, plenty room at the bottom, access way to nano technique, nanoparticles using bottom-up method which are a marvel of nature, and modern alchemy : chemical synthesis of artificial nano structure, understanding of quantum mechanics, STM/AFM, nano metal powder, ceramic nanoparticles, nano structure film, manufacture of nanoparticles using reverse micelle method, carbon nano tube, sol-gel material, nano energy material, nano catalyst nano bio material technology and spintronics.

  9. Nano technology

    International Nuclear Information System (INIS)

    Lee, In Sik

    2002-03-01

    This book is introduction of nano technology, which describes what nano technology is, alpha and omega of nano technology, the future of Korean nano technology and human being's future and nano technology. The contents of this book are nano period is coming, a engine of creation, what is molecular engineering, a huge nano technology, technique on making small things, nano materials with exorbitant possibility, the key of nano world the most desirable nano technology in bio industry, nano development plan of government, the direction of development for nano technology and children of heart.

  10. Circuit model optimization of a nano split ring resonator dimer antenna operating in infrared spectral range

    International Nuclear Information System (INIS)

    Gneiding, N.; Zhuromskyy, O.; Peschel, U.; Shamonina, E.

    2014-01-01

    Metamaterials are comprised of metallic structures with a strong response to incident electromagnetic radiation, like, for example, split ring resonators. The interaction of resonator ensembles with electromagnetic waves can be simulated with finite difference or finite elements algorithms, however, above a certain ensemble size simulations become inadmissibly time or memory consuming. Alternatively a circuit description of metamaterials, a well developed modelling tool at radio and microwave frequencies, allows to significantly increase the simulated ensemble size. This approach can be extended to the IR spectral range with an appropriate set of circuit element parameters accounting for physical effects such as electron inertia and finite conductivity. The model is verified by comparing the coupling coefficients with the ones obtained from the full wave numerical simulations, and used to optimize the nano-antenna design with improved radiation characteristics.

  11. Natural world physical, brain operational, and mind phenomenal space-time

    Science.gov (United States)

    Fingelkurts, Andrew A.; Fingelkurts, Alexander A.; Neves, Carlos F. H.

    2010-06-01

    Concepts of space and time are widely developed in physics. However, there is a considerable lack of biologically plausible theoretical frameworks that can demonstrate how space and time dimensions are implemented in the activity of the most complex life-system - the brain with a mind. Brain activity is organized both temporally and spatially, thus representing space-time in the brain. Critical analysis of recent research on the space-time organization of the brain's activity pointed to the existence of so-called operational space-time in the brain. This space-time is limited to the execution of brain operations of differing complexity. During each such brain operation a particular short-term spatio-temporal pattern of integrated activity of different brain areas emerges within related operational space-time. At the same time, to have a fully functional human brain one needs to have a subjective mental experience. Current research on the subjective mental experience offers detailed analysis of space-time organization of the mind. According to this research, subjective mental experience (subjective virtual world) has definitive spatial and temporal properties similar to many physical phenomena. Based on systematic review of the propositions and tenets of brain and mind space-time descriptions, our aim in this review essay is to explore the relations between the two. To be precise, we would like to discuss the hypothesis that via the brain operational space-time the mind subjective space-time is connected to otherwise distant physical space-time reality.

  12. [Non-operation management of 12 cases with brain abscess demonstrated by CT scan].

    Science.gov (United States)

    Long, J

    1990-12-01

    This paper reported 12 cases with brain abscess demonstrated by CT scan. Using antibiotic management without surgical intervention, in 10 cases the curative effects were satisfactory. The paper indicated that CT scan was very useful in prompt and correct diagnosis of brain abscess and with sequential CT scan medical therapy was feasible. It is significant in treatment of brain abscess especially for the patients who have a poor general condition, have the brain abscess located in important functional area or have multiple abscesses so that the operation is difficult for them.

  13. Vibrotactile Feedback for Brain-Computer Interface Operation

    OpenAIRE

    Cincotti, Febo; Kauhanen, Laura; Aloise, Fabio; Palomäki, Tapio; Caporusso, Nicholas; Jylänki, Pasi; Mattia, Donatella; Babiloni, Fabio; Vanacker, Gerolf; Nuttin, Marnix; Marciani, Maria Grazia; Millán, José del R.

    2007-01-01

    To be correctly mastered, brain-computer interfaces (BCIs) need an uninterrupted flow of feedback to the user. This feedback is usually delivered through the visual channel. Our aim was to explore the benefits of vibrotactile feedback during users' training and control of EEG-based BCI applications. A protocol for delivering vibrotactile feedback, including specific hardware and software arrangements, was specified. In three studies with 33 subjects (i...

  14. Enhanced detection of nitrogen dioxide via combined heating and pulsed UV operation of indium oxide nano-octahedra.

    Science.gov (United States)

    Gonzalez, Oriol; Roso, Sergio; Vilanova, Xavier; Llobet, Eduard

    2016-01-01

    We report on the use of combined heating and pulsed UV light activation of indium oxide gas sensors for enhancing their performance in the detection of nitrogen dioxide in air. Indium oxide nano-octahedra were synthesized at high temperature (900 °C) via vapour-phase transport and screen-printed onto alumina transducers that comprised interdigitated electrodes and a heating resistor. Compared to the standard, constant temperature operation of the sensor, mild heating (e.g., 100 °C) together with pulsed UV light irradiation employing a commercially available, 325 nm UV diode (square, 1 min period, 15 mA drive current signal), results in an up to 80-fold enhancement in sensitivity to nitrogen dioxide. Furthermore, this combined operation method allows for making savings in power consumption that range from 35% to over 80%. These results are achieved by exploiting the dynamics of sensor response under pulsed UV light, which convey important information for the quantitative analysis of nitrogen dioxide.

  15. Enhanced detection of nitrogen dioxide via combined heating and pulsed UV operation of indium oxide nano-octahedra

    Directory of Open Access Journals (Sweden)

    Oriol Gonzalez

    2016-10-01

    Full Text Available We report on the use of combined heating and pulsed UV light activation of indium oxide gas sensors for enhancing their performance in the detection of nitrogen dioxide in air. Indium oxide nano-octahedra were synthesized at high temperature (900 °C via vapour-phase transport and screen-printed onto alumina transducers that comprised interdigitated electrodes and a heating resistor. Compared to the standard, constant temperature operation of the sensor, mild heating (e.g., 100 °C together with pulsed UV light irradiation employing a commercially available, 325 nm UV diode (square, 1 min period, 15 mA drive current signal, results in an up to 80-fold enhancement in sensitivity to nitrogen dioxide. Furthermore, this combined operation method allows for making savings in power consumption that range from 35% to over 80%. These results are achieved by exploiting the dynamics of sensor response under pulsed UV light, which convey important information for the quantitative analysis of nitrogen dioxide.

  16. Effects of a Nano-Silica Additive on the Rock Erosion Characteristics of a SC-CO2 Jet under Various Operating Conditions

    Directory of Open Access Journals (Sweden)

    Man Huang

    2017-02-01

    Full Text Available In order to improve the erosion capacity of a supercritical carbon dioxide (SC-CO2 jet, the influence of a nano-silica additive on the rock erosion characteristics was experimentally investigated. By impinging the SC-CO2 jets with nano-silica mass fractions of 0 wt % (pure SC-CO2 jet, 3 wt %, 6 wt %, 9 wt %, 12 wt %, 15 wt %, and 18 wt % on specimens of red sandstone, the erosion volumes under various operating conditions were measured and analyzed. Results show that an appropriate amount of nano-silica additive can greatly enhance the erosion ability of a SC-CO2 jet. The effect on the erosion ability largely depends on the operating conditions. For instance, when the other conditions are fixed, 6 wt %, 9 wt %, 12 wt %, and 15 wt % were the optimum mass fractions, successively, with the inlet pressure increasing from 30 MPa to 60 MPa. With the increase in ambient pressure, the optimum mass fraction is unchanged under the constant inlet pressure, while it increases under the constant pressure drop. Additionally, the optimum mass fraction decreases when the fluid temperature increases. In addition, the optimal standoff distances are about five times the nozzle diameter of the nano-silica SC-CO2 jet, and three times for the pure jet. This research provides a new method for effectively enhancing the rock erosion performance of a SC-CO2 jet.

  17. Synchronization and chaos in spin-transfer-torque nano-oscillators coupled via a high-speed operational amplifier

    International Nuclear Information System (INIS)

    Sanid, C; Murugesh, S

    2014-01-01

    We propose a system of two coupled spin-torque nano-oscillators (STNOs), one driver and another response, and demonstrate using numerical studies the synchronization of the response system to the frequency of the driver system. To this end we use a high-speed operational amplifier in the form of a voltage follower, which essentially isolates the drive system from the response system. We find the occurrence of 1 : 1 as well as 2 : 1 synchronization in the system, wherein the oscillators show limit cycle dynamics. An increase in power output is noticed when the two oscillators are locked in 1 : 1 synchronization. Moreover in the crossover region between these two synchronization dynamics we show the existence of chaotic dynamics in the slave system. The coupled dynamics under periodic forcing, using a small ac input current in addition to that of the dc part, is also studied. The slave oscillator is seen to retain its qualitative identity in the parameter space in spite of being fed in, at times, a chaotic signal. Such electrically coupled STNOs will be highly useful in fabricating commercial spin-valve oscillators with high power output, when integrated with other spintronic devices. (paper)

  18. Common brain regions underlying different arithmetic operations as revealed by conjunct fMRI-BOLD activation.

    Science.gov (United States)

    Fehr, Thorsten; Code, Chris; Herrmann, Manfred

    2007-10-03

    The issue of how and where arithmetic operations are represented in the brain has been addressed in numerous studies. Lesion studies suggest that a network of different brain areas are involved in mental calculation. Neuroimaging studies have reported inferior parietal and lateral frontal activations during mental arithmetic using tasks of different complexities and using different operators (addition, subtraction, etc.). Indeed, it has been difficult to compare brain activation across studies because of the variety of different operators and different presentation modalities used. The present experiment examined fMRI-BOLD activity in participants during calculation tasks entailing different arithmetic operations -- addition, subtraction, multiplication and division -- of different complexities. Functional imaging data revealed a common activation pattern comprising right precuneus, left and right middle and superior frontal regions during all arithmetic operations. All other regional activations were operation specific and distributed in prominently frontal, parietal and central regions when contrasting complex and simple calculation tasks. The present results largely confirm former studies suggesting that activation patterns due to mental arithmetic appear to reflect a basic anatomical substrate of working memory, numerical knowledge and processing based on finger counting, and derived from a network originally related to finger movement. We emphasize that in mental arithmetic research different arithmetic operations should always be examined and discussed independently of each other in order to avoid invalid generalizations on arithmetics and involved brain areas.

  19. Vibrotactile Feedback for Brain-Computer Interface Operation

    Directory of Open Access Journals (Sweden)

    Febo Cincotti

    2007-01-01

    Full Text Available To be correctly mastered, brain-computer interfaces (BCIs need an uninterrupted flow of feedback to the user. This feedback is usually delivered through the visual channel. Our aim was to explore the benefits of vibrotactile feedback during users' training and control of EEG-based BCI applications. A protocol for delivering vibrotactile feedback, including specific hardware and software arrangements, was specified. In three studies with 33 subjects (including 3 with spinal cord injury, we compared vibrotactile and visual feedback, addressing: (I the feasibility of subjects' training to master their EEG rhythms using tactile feedback; (II the compatibility of this form of feedback in presence of a visual distracter; (III the performance in presence of a complex visual task on the same (visual or different (tactile sensory channel. The stimulation protocol we developed supports a general usage of the tactors; preliminary experimentations. All studies indicated that the vibrotactile channel can function as a valuable feedback modality with reliability comparable to the classical visual feedback. Advantages of using a vibrotactile feedback emerged when the visual channel was highly loaded by a complex task. In all experiments, vibrotactile feedback felt, after some training, more natural for both controls and SCI users.

  20. Intra-operative neurophysiological mapping and monitoring during brain tumour surgery in children: an update.

    Science.gov (United States)

    Coppola, Angela; Tramontano, Vincenzo; Basaldella, Federica; Arcaro, Chiara; Squintani, Giovanna; Sala, Francesco

    2016-10-01

    Over the past decade, the reluctance to operate in eloquent brain areas has been reconsidered in the light of the advent of new peri-operative functional neuroimaging techniques and new evidence from neuro-oncology. To maximise tumour resection while minimising morbidity should be the goal of brain surgery in children as much as it is in adults, and preservation of brain functions is critical in the light of the increased survival and the expectations in terms of quality of life. Intra-operative neurophysiology is the gold standard to localise and preserve brain functions during surgery and is increasingly used in paediatric neurosurgery. Yet, the developing nervous system has peculiar characteristics in terms of anatomical and physiological maturation, and some technical aspects need to be tailored for its use in children, especially in infants. This paper will review the most recent advances in the field of intra-operative neurophysiology (ION) techniques during brain surgery, focussing on those aspects that are relevant to the paediatric neurosurgery practice.

  1. PLGA nanoparticles prepared by nano-emulsion templating using low-energy methods as efficient nanocarriers for drug delivery across the blood-brain barrier.

    Science.gov (United States)

    Fornaguera, C; Dols-Perez, A; Calderó, G; García-Celma, M J; Camarasa, J; Solans, C

    2015-08-10

    Neurodegenerative diseases have an increased prevalence and incidence nowadays, mainly due to aging of the population. In addition, current treatments lack efficacy, mostly due to the presence of the blood-brain barrier (BBB) that limits the penetration of the drugs to the central nervous system. Therefore, novel drug delivery systems are required. Polymeric nanoparticles have been reported to be appropriate for this purpose. Specifically, the use of poly-(lactic-co-glycolic acid) (PLGA) seems to be advantageous due to its biocompatibility and biodegradability that ensure safe therapies. In this work, a novel approximation to develop loperamide-loaded nanoparticles is presented: their preparation by nano-emulsion templating using a low-energy method (the phase inversion composition, PIC, method). This nano-emulsification approach is a simple and very versatile technology, which allows a precise size control and it can be performed at mild process conditions. Drug-loaded PLGA nanoparticles were obtained using safe components by solvent evaporation of template nano-emulsions. Characterization of PLGA nanoparticles was performed, together with the study of the BBB crossing. The in vivo results of measuring the analgesic effect using the hot-plate test evidenced that the designed PLGA loperamide-loaded nanoparticles are able to efficiently cross the BBB, with high crossing efficiencies when their surface is functionalized with an active targeting moiety (a monoclonal antibody against the transferrin receptor). These results, together with the nanoparticle characterization performed here are expected to provide sufficient evidences to end up to clinical trials in the near future. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Novel theory of the human brain: information-commutation basis of architecture and principles of operation

    Directory of Open Access Journals (Sweden)

    Bryukhovetskiy AS

    2015-02-01

    Full Text Available Andrey S Bryukhovetskiy Center for Biomedical Technologies, Federal Research and Clinical Center for Specialized Types of Medical Assistance and Medical Technologies of the Federal Medical Biological Agency, NeuroVita Clinic of Interventional and Restorative Neurology and Therapy, Moscow, Russia Abstract: Based on the methodology of the informational approach and research of the genome, proteome, and complete transcriptome profiles of different cells in the nervous tissue of the human brain, the author proposes a new theory of information-commutation organization and architecture of the human brain which is an alternative to the conventional systemic connective morphofunctional paradigm of the brain framework. Informational principles of brain operation are defined: the modular principle, holographic principle, principle of systematicity of vertical commutative connection and complexity of horizontal commutative connection, regulatory principle, relay principle, modulation principle, “illumination” principle, principle of personalized memory and intellect, and principle of low energy consumption. The author demonstrates that the cortex functions only as a switchboard and router of information, while information is processed outside the nervous tissue of the brain in the intermeningeal space. The main structural element of information-commutation in the brain is not the neuron, but information-commutation modules that are subdivided into receiver modules, transmitter modules, and subscriber modules, forming a vertical architecture of nervous tissue in the brain as information lines and information channels, and a horizontal architecture as central, intermediate, and peripheral information-commutation platforms. Information in information-commutation modules is transferred by means of the carriers that are characteristic to the specific information level from inductome to genome, transcriptome, proteome, metabolome, secretome, and magnetome

  3. Enhanced Therapeutic Potential of Nano-Curcumin Against Subarachnoid Hemorrhage-Induced Blood-Brain Barrier Disruption Through Inhibition of Inflammatory Response and Oxidative Stress.

    Science.gov (United States)

    Zhang, Zong-Yong; Jiang, Ming; Fang, Jie; Yang, Ming-Feng; Zhang, Shuai; Yin, Yan-Xin; Li, Da-Wei; Mao, Lei-Lei; Fu, Xiao-Yan; Hou, Ya-Jun; Fu, Xiao-Ting; Fan, Cun-Dong; Sun, Bao-Liang

    2017-01-01

    Curcumin and nano-curcumin both exhibit neuroprotective effects in early brain injury (EBI) after experimental subarachnoid hemorrhage (SAH). However, the mechanism that whether curcumin and its nanoparticles affect the blood-brain barrier (BBB) following SAH remains unclear. This study investigated the effect of curcumin and the poly(lactide-co-glycolide) (PLGA)-encapsulated curcumin nanoparticles (Cur-NPs) on BBB disruption and evaluated the possible mechanism underlying BBB dysfunction in EBI using the endovascular perforation rat SAH model. The results indicated that Cur-NPs showed enhanced therapeutic effects than that of curcumin in improving neurological function, reducing brain water content, and Evans blue dye extravasation after SAH. Mechanically, Cur-NPs attenuated BBB dysfunction after SAH by preventing the disruption of tight junction protein (ZO-1, occludin, and claudin-5). Cur-NPs also up-regulated glutamate transporter-1 and attenuated glutamate concentration of cerebrospinal fluid following SAH. Moreover, inhibition of inflammatory response and microglia activation both contributed to Cur-NPs' protective effects. Additionally, Cur-NPs markedly suppressed SAH-mediated oxidative stress and eventually reversed SAH-induced cell apoptosis in rats. Our findings revealed that the strategy of using Cur-NPs could be a promising way in improving neurological function in EBI after experimental rat SAH.

  4. Performance Investigation of Automobile Radiator Operated with ZnFe2O4 Nano Fluid based Coolant

    Directory of Open Access Journals (Sweden)

    Tripathi Ajay

    2015-01-01

    Full Text Available The cooling system of an Automobile plays an important role in its performance, consists of two main parts, known as radiator and fan. Improving thermal efficiency of engine leads to increase the engine's performance, decline the fuel consumption and decrease the pollution emissions. Water and ethylene glycol as conventional coolants have been widely used in radiators of an automotive industry for many years. These heat transfer fluids offer low thermal conductivity. With the advancement of nanotechnology, the new generation of heat transfer fluids called, “nanofluids” have been developed and researchers found that these fluids offer higher thermal conductivity compared to that of conventional coolants. This study focused on the preparation of Zinc based nanofluids (ZnFe2O4 using chemical co-precipitation method and its application in an automotive cooling system along with mixture of ethylene glycol and water (50:50. Relevant input data, nanofluids properties and empirical correlations were obtained from literatures to investigate the heat transfer enhancement of an automotive car radiator operated with nano fluid-based coolants. It was observed that, overall heat transfer coefficient and heat transfer rate in engine cooling system increased with the usage of nanofluids (with ethylene glycol the base-fluid compared to ethylene glycol (i.e. base-fluid alone. It is observed that, about 78% of heat transfer enhancement could be achieved with the addition of 1% ZnFe2O4 particles in a base fluid at the Reynolds number of 84.4x103 and 39.5x103 for air and coolant respectively

  5. Pre- and post-operative values of serum CRP in patients undergoing surgery for brain tumour

    International Nuclear Information System (INIS)

    Syeda, T.; Rizvi, H.A.; Hashim, A.S.

    2014-01-01

    Objective: To determine the concentration of C-reactive protein in pre- and post-operative serum samples of brain tumour patients in order to detect the potential risks of post-operative infections. Methods: Serum C-reactive protein was measured on pre- and post-operative Day 1, Day 2 and Day 7 in 18 patients who underwent surgery for brain tumours. The study was performed at the Neurosurgical Ward, Jinnah Postgraduate Medical Centre, Karachi, from May 2007 to April 2008. Mean pre-operative patients and control values were compared using Mann-Whitney or Wilcoxon tests for comparing between pre- and post-operative values. P-value was considered significant at 5.0mg/L but no statistically significant difference was found when compared with healthy controls, with mean 4.4+-6.6 and 0.9+-0.7, respectively. Significantly raised serum concentrations were observed in all post-operative samples when compared with pre-operative samples. Serum CRP concentrations significantly increased post-operatively on Day 1, with mean value of 102.9+-82.0mg/L (p<0.0005), and further increased on Day 2 with mean value of 166.9+-128.1mg/L (p<0.0005), but declined on Day 7, with mean value of 42.7+-63.6mg/L (p<0.005). Conclusion: Pre-operative serum C-reactive protein concentrations of 28% of the patients were elevated, suggesting an association with brain tumours. Post-operative serum concentrations were significantly higher than those noted before the surgery. Absence of a fall of concentration from peak value on post-operative Day 2 or a secondary rise from post-operative Day 7 could be alarming for inter-current infection. (author)

  6. Simultaneous recording of brain extracellular glucose, spike and local field potential in real time using an implantable microelectrode array with nano-materials

    Science.gov (United States)

    Wei, Wenjing; Song, Yilin; Fan, Xinyi; Zhang, Song; Wang, Li; Xu, Shengwei; Wang, Mixia; Cai, Xinxia

    2016-03-01

    Glucose is the main substrate for neurons in the central nervous system. In order to efficiently characterize the brain glucose mechanism, it is desirable to determine the extracellular glucose dynamics as well as the corresponding neuroelectrical activity in vivo. In the present study, we fabricated an implantable microelectrode array (MEA) probe composed of platinum electrochemical and electrophysiology microelectrodes by standard micro electromechanical system (MEMS) processes. The MEA probe was modified with nano-materials and implanted in a urethane-anesthetized rat for simultaneous recording of striatal extracellular glucose, local field potential (LFP) and spike on the same spatiotemporal scale when the rat was in normoglycemia, hypoglycemia and hyperglycemia. During these dual-mode recordings, we observed that increase of extracellular glucose enhanced the LFP power and spike firing rate, while decrease of glucose had an opposite effect. This dual mode MEA probe is capable of examining specific spatiotemporal relationships between electrical and chemical signaling in the brain, which will contribute significantly to improve our understanding of the neuron physiology.

  7. Simultaneous recording of brain extracellular glucose, spike and local field potential in real time using an implantable microelectrode array with nano-materials

    International Nuclear Information System (INIS)

    Wei, Wenjing; Song, Yilin; Fan, Xinyi; Zhang, Song; Wang, Li; Xu, Shengwei; Wang, Mixia; Cai, Xinxia

    2016-01-01

    Glucose is the main substrate for neurons in the central nervous system. In order to efficiently characterize the brain glucose mechanism, it is desirable to determine the extracellular glucose dynamics as well as the corresponding neuroelectrical activity in vivo. In the present study, we fabricated an implantable microelectrode array (MEA) probe composed of platinum electrochemical and electrophysiology microelectrodes by standard micro electromechanical system (MEMS) processes. The MEA probe was modified with nano-materials and implanted in a urethane-anesthetized rat for simultaneous recording of striatal extracellular glucose, local field potential (LFP) and spike on the same spatiotemporal scale when the rat was in normoglycemia, hypoglycemia and hyperglycemia. During these dual-mode recordings, we observed that increase of extracellular glucose enhanced the LFP power and spike firing rate, while decrease of glucose had an opposite effect. This dual mode MEA probe is capable of examining specific spatiotemporal relationships between electrical and chemical signaling in the brain, which will contribute significantly to improve our understanding of the neuron physiology. (paper)

  8. Bio-Mechanical Model of the Brain for a Per-Operative Image-Guided Neuronavigator Compensating for "Brain-Shift" Deformations

    OpenAIRE

    Bucki, Marek; Lobos, Claudio; Payan, Yohan

    2007-01-01

    International audience; In this paper we present a methodology to address the problem of brain tissue deformation referred to as 'brain-shift'. This deformation occurs throughout a neurosurgery intervention and strongly alters the accuracy of the neuronavigation systems used to date in clinical routine which rely solely on pre-operative patient imaging to locate the surgical target, such as a tumour or a functional area. After a general description of the framework of our intra-operative imag...

  9. Multi-objective optimization and exergetic-sustainability of an irreversible nano scale Braysson cycle operating with Ma

    Directory of Open Access Journals (Sweden)

    Mohammad H. Ahmadi

    2016-06-01

    Full Text Available Nano technology is developed in this decade and changes the way of life. Moreover, developing nano technology has effect on the performance of the materials and consequently improves the efficiency and robustness of them. So, nano scale thermal cycles will be probably engaged in the near future. In this paper, a nano scale irreversible Braysson cycle is studied thermodynamically for optimizing the performance of the Braysson cycle. In the aforementioned cycle an ideal Maxwell–Boltzmann gas is used as a working fluid. Furthermore, three different plans are used for optimizing with multi-objectives; though, the outputs of the abovementioned plans are assessed autonomously. Throughout the first plan, with the purpose of maximizing the ecological coefficient of performance and energy efficiency of the system, multi-objective optimization algorithms are used. Furthermore, in the second plan, two objective functions containing the ecological coefficient of performance and the dimensionless Maximum available work are maximized synchronously by utilizing multi-objective optimization approach. Finally, throughout the third plan, three objective functions involving the dimensionless Maximum available work, the ecological coefficient of performance and energy efficiency of the system are maximized synchronously by utilizing multi-objective optimization approach. The multi-objective evolutionary approach based on the non-dominated sorting genetic algorithm approach is used in this research. Making a decision is performed by three different decision makers comprising linear programming approaches for multidimensional analysis of preference and an approach for order of preference by comparison with ideal answer and Bellman–Zadeh. Lastly, analysis of error is employed to determine deviation of the outcomes gained from each plan.

  10. Performance assessment and optimization of an irreversible nano-scale Stirling engine cycle operating with Maxwell-Boltzmann gas

    Science.gov (United States)

    Ahmadi, Mohammad H.; Ahmadi, Mohammad-Ali; Pourfayaz, Fathollah

    2015-09-01

    Developing new technologies like nano-technology improves the performance of the energy industries. Consequently, emerging new groups of thermal cycles in nano-scale can revolutionize the energy systems' future. This paper presents a thermo-dynamical study of a nano-scale irreversible Stirling engine cycle with the aim of optimizing the performance of the Stirling engine cycle. In the Stirling engine cycle the working fluid is an Ideal Maxwell-Boltzmann gas. Moreover, two different strategies are proposed for a multi-objective optimization issue, and the outcomes of each strategy are evaluated separately. The first strategy is proposed to maximize the ecological coefficient of performance (ECOP), the dimensionless ecological function (ecf) and the dimensionless thermo-economic objective function ( F . Furthermore, the second strategy is suggested to maximize the thermal efficiency ( η), the dimensionless ecological function (ecf) and the dimensionless thermo-economic objective function ( F). All the strategies in the present work are executed via a multi-objective evolutionary algorithms based on NSGA∥ method. Finally, to achieve the final answer in each strategy, three well-known decision makers are executed. Lastly, deviations of the outcomes gained in each strategy and each decision maker are evaluated separately.

  11. Nano dentistry

    International Nuclear Information System (INIS)

    Oh, S.; Park, Y.B.; Kim, S.; Jin, S.

    2014-01-01

    Nano technology in dentistry has drawn many scientists’ and clinicians’ attention to significant advances in the diagnosis, treatment, and prevention of oral disease. Also, nano materials in dentistry have been studied to overcome the physical and chemical characteristics of conventional dental materials. These interesting facts are the motivation of this special issue. The presented issue provides a variety of topics in the field of dentistry such as novel nano filled composite resin, the cytotoxicity of nanoparticles deposited on orthodontic bands, the osseointegration of 3D nano scaffold, and nano surface treated implant.

  12. Intra-operative 3-T MRI for paediatric brain tumours: challenges and perspectives

    International Nuclear Information System (INIS)

    Abernethy, L.J.; Avula, S.; Hughes, G.M.; Wright, E.J.; Mallucci, C.L.

    2012-01-01

    MRI is the ideal modality for imaging intracranial tumours. Intraoperative MRI (ioMRI) makes it possible to obtain scans during a neurosurgical operation that can aid complete macroscopic tumour resection - a major prognostic factor in the majority of brain tumours in children. Intra-operative MRI can also help limit damage to normal brain tissue. It therefore has the potential to improve the survival of children with brain tumours and to minimise morbidity, including neurological deficits. The use of ioMRI is also likely to reduce the need for second look surgery, and may reduce the need for chemotherapy and radiotherapy. High-field MRI systems provide better anatomical information and also enable effective utilisation of advanced MRI techniques such as perfusion imaging, diffusion tensor imaging, and magnetic resonance spectroscopy. However, high-field ioMRI facilities require substantial capital investment, and careful planning is required for optimal benefit. Safe ioMRI requires meticulous attention to detail and rigorous application of magnetic field safety precautions. Interpretation of ioMRI can be challenging and requires experience and understanding of artefacts that are common in the intra-operative setting. (orig.)

  13. Humanlike robot hands controlled by brain activity arouse illusion of ownership in operators

    Science.gov (United States)

    Alimardani, Maryam; Nishio, Shuichi; Ishiguro, Hiroshi

    2013-08-01

    Operators of a pair of robotic hands report ownership for those hands when they hold image of a grasp motion and watch the robot perform it. We present a novel body ownership illusion that is induced by merely watching and controlling robot's motions through a brain machine interface. In past studies, body ownership illusions were induced by correlation of such sensory inputs as vision, touch and proprioception. However, in the presented illusion none of the mentioned sensations are integrated except vision. Our results show that during BMI-operation of robotic hands, the interaction between motor commands and visual feedback of the intended motions is adequate to incorporate the non-body limbs into one's own body. Our discussion focuses on the role of proprioceptive information in the mechanism of agency-driven illusions. We believe that our findings will contribute to improvement of tele-presence systems in which operators incorporate BMI-operated robots into their body representations.

  14. Delivery of Nano-Tethered Therapies to Brain Metastases of Primary Breast Cancer Using a Cellular Trojan Horse

    Science.gov (United States)

    2015-12-01

    empirical method was developed to simulate photon transport in tissue based on the acquired medical images of an individual patient (CT and MRI ) with... MRI , etc. In the current work we have developed a fast voxel based empirical approach which can estimate photon fluence in the brain and evaluate...These tools provide the capability to develop and optimize treatment plans for optimal release of pharmaceuticals to metastatic breast cancer in the

  15. Framework for a low-cost intra-operative image-guided neuronavigator including brain shift compensation

    OpenAIRE

    Bucki, Marek; Lobos, Claudio; Payan, Yohan

    2007-01-01

    In this paper we present a methodology to address the problem of brain tissue deformation referred to as 'brain-shift'. This deformation occurs throughout a neurosurgery intervention and strongly alters the accuracy of the neuronavigation systems used to date in clinical routine which rely solely on pre-operative patient imaging to locate the surgical target, such as a tumour or a functional area. After a general description of the framework of our intra-operative image-guided system, we desc...

  16. Visual symptomatology and referral patterns for Operation Iraqi Freedom and Operation Enduring Freedom veterans with traumatic brain injury.

    Science.gov (United States)

    Bulson, Ryan; Jun, Weon; Hayes, John

    2012-01-01

    Advances in protective armor technology and changes in the "patterns of war" have created a population of Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) veterans with traumatic brain injury (TBI) that provide a unique challenge to Department of Veterans Affairs (VA) healthcare practitioners. The purpose of the study was to determine the frequency of symptomatic ocular and visual sequelae of TBI in OIF/OEF veterans at the Portland VA Medical Center, a Polytrauma Support Clinic Team site. A retrospective analysis of 100 OIF/OEF veterans with TBI was conducted to determine the prevalence of ocular and visual complaints. Referral patterns were also investigated. Visual symptoms were reported in approximately 50% of veterans with TBI. Loss of consciousness, but not number of deployments or number of blast exposures, was found to have a statistically significant association with severity of reported visual symptoms. The most commonly reported symptoms included blurred vision (67%), photosensitivity (50%), and accommodative problems (40%). Visual symptoms of OIF/OEF veterans at the Portland VA Medical Center are reported at slightly lower rates than similar studies conducted at the Palo Alto and Edward Hines Jr VA facilities.

  17. Studies on the reliability of high-field intra-operative MRI in brain glioma resection

    Directory of Open Access Journals (Sweden)

    Zhi-jun SONG

    2011-07-01

    Full Text Available Objective To evaluate the reliability of high-field intra-operative magnetic resonance imaging(iMRI in detecting the residual tumors during glioma resection.Method One hundred and thirty-one cases of brain glioma(69 males and 62 females,aged from 7 to 79 years with mean of 39.6 years hospitalized from Nov.2009 to Aug.2010 were involved in present study.All the patients were evaluated using magnetic resonance imaging(MRI before the operation.The tumors were resected under conventional navigation microscope,and the high-field iMRI was used for all the patients when the operators considered the tumor was satisfactorily resected,while the residual tumor was difficult to detect under the microscope,but resected after being revealed by high-field iMRI.Histopathological examination was performed.The patients without residual tumors recieved high-field MRI scan at day 4 or 5 after operation to evaluate the accuracy of high-field iMRI during operation.Results High quality intra-operative images were obtained by using high-field iMRI.Twenty-eight cases were excluded because their residual tumors were not resected due to their location too close to functional area.Combined with the results of intra-operative histopathological examination and post-operative MRI at the early recovery stage,the sensitivity of high-field iMRI in residual tumor diagnosis was 98.0%(49/50,the specificity was 94.3%(50/53,and the accuracy was 96.1%(99/103.Conclusion High-quality intra-operative imaging could be acquired by high-field iMRI,which maybe used as a safe and reliable method in detecting the residual tumors during glioma resection.

  18. Proteomic analysis of proteins expressing in regions of rat brain by a combination of SDS-PAGE with nano-liquid chromatography-quadrupole-time of flight tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    Maekawa Tsuyoshi

    2010-07-01

    Full Text Available Abstract Background Most biological functions controlled by the brain and their related disorders are closely associated with activation in specific regions of the brain. Neuroproteomics has been applied to the analysis of whole brain, and the general pattern of protein expression in all regions has been elucidated. However, the comprehensive proteome of each brain region remains unclear. Results In this study, we carried out comparative proteomics of six regions of the adult rat brain: thalamus, hippocampus, frontal cortex, parietal cortex, occipital cortex, and amygdala using semi-quantitative analysis by Mascot Score of the identified proteins. In order to identify efficiently the proteins that are present in the brain, the proteins were separated by a combination of SDS-PAGE on a C18 column-equipped nano-liquid chromatograph, and analyzed by quadrupole-time of flight-tandem-mass spectrometry. The proteomic data show 2,909 peptides in the rat brain, with more than 200 identified as region-abundant proteins by semi-quantitative analysis. The regions containing the identified proteins are membrane (20.0%, cytoplasm (19.5%, mitochondrion (17.1%, cytoskeleton (8.2%, nucleus (4.7%, extracellular region (3.3%, and other (18.0%. Of the identified proteins, the expressions of glial fibrillary acidic protein, GABA transporter 3, Septin 5, heat shock protein 90, synaptotagmin, heat shock protein 70, and pyruvate kinase were confirmed by immunoblotting. We examined the distributions in rat brain of GABA transporter 3, glial fibrillary acidic protein, and heat shock protein 70 by immunohistochemistry, and found that the proteins are localized around the regions observed by proteomic analysis and immunoblotting. IPA analysis indicates that pathways closely related to the biological functions of each region may be activated in rat brain. Conclusions These observations indicate that proteomics in each region of adult rat brain may provide a novel way to

  19. Controlling micro- and nano-environment of tumor and stem cells for novel research and therapy of brain cancer

    Science.gov (United States)

    Smith, Christopher Lloyd

    The use of modern technologies in cancer research has engendered a great deal of excitement. Many of these advanced approaches involve in-depth mathematical analyses of the inner working of cells, via genomic and proteomic analyses. However these techniques may not be ideal for the study of complex cell phenotypes and behaviors. This dissertation explores cancer and potential therapies through phenotypic analysis of cell behaviors, an alternative approach. We employ this experimental framework to study brain cancer (glioma), a particularly formidable example of this diverse ailment. Through the application of micro- and nanotechnology, we carefully control the surrounding environments of cells to understand their responses to various cues and to manipulate their behaviors. Subsequently we obtain clinically relevant information that allows better understanding of glioma, and enhancement of potential therapies. We first aim to address brain tumor dispersal, through analysis of cell migration. Utilizing nanometer-scale topographic models of the extracellular matrix, we study the migratory response of glioma cells to various stimuli in vitro. Second, we implement knowledge gained from these investigations to define characteristics of tumor progression in patients, and to develop treatments inhibiting cell migration. Next we use microfluidic and nanotopographic models to study the behaviors of stem cells in vitro. Here we attempt to improve their abilities to deliver therapeutic proteins to cancer, an innovative treatment approach. We analyze the multi-step process by which adipose-derived stem cells naturally home to tumor sites, and identify numerous environmental perturbations to enhance this behavior. Finally, we attempt to demonstrate that these cell culture-based manipulations can enhance the localization of adipose stem cells to glioma in vivo using animal models. Throughout this work we utilize environmental cues to analyze and induce particular behaviors in

  20. The Vertebrate Brain, Evidence of Its Modular Organization and Operating System: Insights into the Brain's Basic Units of Structure, Function, and Operation and How They Influence Neuronal Signaling and Behavior.

    Science.gov (United States)

    Baslow, Morris H

    2011-01-01

    The human brain is a complex organ made up of neurons and several other cell types, and whose role is processing information for use in eliciting behaviors. However, the composition of its repeating cellular units for both structure and function are unresolved. Based on recent descriptions of the brain's physiological "operating system", a function of the tri-cellular metabolism of N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) for supply of energy, and on the nature of "neuronal words and languages" for intercellular communication, insights into the brain's modular structural and functional units have been gained. In this article, it is proposed that the basic structural unit in brain is defined by its physiological operating system, and that it consists of a single neuron, and one or more astrocytes, oligodendrocytes, and vascular system endothelial cells. It is also proposed that the basic functional unit in the brain is defined by how neurons communicate, and consists of two neurons and their interconnecting dendritic-synaptic-dendritic field. Since a functional unit is composed of two neurons, it requires two structural units to form a functional unit. Thus, the brain can be envisioned as being made up of the three-dimensional stacking and intertwining of myriad structural units which results not only in its gross structure, but also in producing a uniform distribution of binary functional units. Since the physiological NAA-NAAG operating system for supply of energy is repeated in every structural unit, it is positioned to control global brain function.

  1. What's Behind a "+" Sign? Perceiving an Arithmetic Operator Recruits Brain Circuits for Spatial Orienting.

    Science.gov (United States)

    Mathieu, Romain; Epinat-Duclos, Justine; Sigovan, Monica; Breton, Audrey; Cheylus, Anne; Fayol, Michel; Thevenot, Catherine; Prado, Jérôme

    2018-05-01

    Do mathematical symbols evoke spatial representations? Although behavioral studies have long demonstrated interactions between space and the processing of Arabic digits, how to interpret these results remains controversial. Here, we tested whether activity in regions supporting spatial processing contributes to the processing of symbols conveying fundamental arithmetic concepts-such as operation signs-even in the absence of associated digits. Using functional magnetic resonance imaging, we show that merely perceiving a "+" sign triggers activity in brain regions that support the orienting of spatial attention in adults. Activity in these regions was greater for "+" than for "×" signs, indicating that it is modulated by whether an operator reflects an operation that evokes numerical manipulation (rather than rote memorization). Finally, the degree to which subjects activated a spatial region in response to a "+" sign was correlated with the degree to which subjects benefited from being briefly presented with that sign before having to calculate a single-digit addition problem, an effect termed operator-priming. Therefore, not only are some arithmetic operators linked to spatial intuitions, but such intuitions might also have an important role during arithmetic calculation. More generally, our findings support the view that mathematical symbols inherently evoke spatial representations.

  2. Linking EEG signals, brain functions and mental operations: Advantages of the Laplacian transformation.

    Science.gov (United States)

    Vidal, Franck; Burle, Boris; Spieser, Laure; Carbonnell, Laurence; Meckler, Cédric; Casini, Laurence; Hasbroucq, Thierry

    2015-09-01

    Electroencephalography (EEG) is a very popular technique for investigating brain functions and/or mental processes. To this aim, EEG activities must be interpreted in terms of brain and/or mental processes. EEG signals being a direct manifestation of neuronal activity it is often assumed that such interpretations are quite obvious or, at least, straightforward. However, they often rely on (explicit or even implicit) assumptions regarding the structures supposed to generate the EEG activities of interest. For these assumptions to be used appropriately, reliable links between EEG activities and the underlying brain structures must be established. Because of volume conduction effects and the mixture of activities they induce, these links are difficult to establish with scalp potential recordings. We present different examples showing how the Laplacian transformation, acting as an efficient source separation method, allowed to establish more reliable links between EEG activities and brain generators and, ultimately, with mental operations. The nature of those links depends on the depth of inferences that can vary from weak to strong. Along this continuum, we show that 1) while the effects of experimental manipulation can appear widely distributed with scalp potentials, Laplacian transformation allows to reveal several generators contributing (in different manners) to these modulations, 2) amplitude variations within the same set of generators can generate spurious differences in scalp potential topographies, often interpreted as reflecting different source configurations. In such a case, Laplacian transformation provides much more similar topographies, evidencing the same generator(s) set, and 3) using the LRP as an index of response activation most often produces ambiguous results, Laplacian-transformed response-locked ERPs obtained over motor areas allow resolving these ambiguities. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Applications of operant learning theory to the management of challenging behavior after traumatic brain injury.

    Science.gov (United States)

    Wood, Rodger Ll; Alderman, Nick

    2011-01-01

    For more than 3 decades, interventions derived from learning theory have been delivered within a neurobehavioral framework to manage challenging behavior after traumatic brain injury with the aim of promoting engagement in the rehabilitation process and ameliorating social handicap. Learning theory provides a conceptual structure that facilitates our ability to understand the relationship between challenging behavior and environmental contingencies, while accommodating the constraints upon learning imposed by impaired cognition. Interventions derived from operant learning theory have most frequently been described in the literature because this method of associational learning provides good evidence for the effectiveness of differential reinforcement methods. This article therefore examines the efficacy of applying operant learning theory to manage challenging behavior after TBI as well as some of the limitations of this approach. Future developments in the application of learning theory are also considered.

  4. Intra-operative multi-site stimulation: Expanding methodology for cortical brain mapping of language functions.

    Science.gov (United States)

    Gonen, Tal; Gazit, Tomer; Korn, Akiva; Kirschner, Adi; Perry, Daniella; Hendler, Talma; Ram, Zvi

    2017-01-01

    Direct cortical stimulation (DCS) is considered the gold-standard for functional cortical mapping during awake surgery for brain tumor resection. DCS is performed by stimulating one local cortical area at a time. We present a feasibility study using an intra-operative technique aimed at improving our ability to map brain functions which rely on activity in distributed cortical regions. Following standard DCS, Multi-Site Stimulation (MSS) was performed in 15 patients by applying simultaneous cortical stimulations at multiple locations. Language functioning was chosen as a case-cognitive domain due to its relatively well-known cortical organization. MSS, performed at sites that did not produce disruption when applied in a single stimulation point, revealed additional language dysfunction in 73% of the patients. Functional regions identified by this technique were presumed to be significant to language circuitry and were spared during surgery. No new neurological deficits were observed in any of the patients following surgery. Though the neuro-electrical effects of MSS need further investigation, this feasibility study may provide a first step towards sophistication of intra-operative cortical mapping.

  5. Simultaneous bilateral stereotactic procedure for deep brain stimulation implants: a significant step for reducing operation time.

    Science.gov (United States)

    Fonoff, Erich Talamoni; Azevedo, Angelo; Angelos, Jairo Silva Dos; Martinez, Raquel Chacon Ruiz; Navarro, Jessie; Reis, Paul Rodrigo; Sepulveda, Miguel Ernesto San Martin; Cury, Rubens Gisbert; Ghilardi, Maria Gabriela Dos Santos; Teixeira, Manoel Jacobsen; Lopez, William Omar Contreras

    2016-07-01

    OBJECT Currently, bilateral procedures involve 2 sequential implants in each of the hemispheres. The present report demonstrates the feasibility of simultaneous bilateral procedures during the implantation of deep brain stimulation (DBS) leads. METHODS Fifty-seven patients with movement disorders underwent bilateral DBS implantation in the same study period. The authors compared the time required for the surgical implantation of deep brain electrodes in 2 randomly assigned groups. One group of 28 patients underwent traditional sequential electrode implantation, and the other 29 patients underwent simultaneous bilateral implantation. Clinical outcomes of the patients with Parkinson's disease (PD) who had undergone DBS implantation of the subthalamic nucleus using either of the 2 techniques were compared. RESULTS Overall, a reduction of 38.51% in total operating time for the simultaneous bilateral group (136.4 ± 20.93 minutes) as compared with that for the traditional consecutive approach (220.3 ± 27.58 minutes) was observed. Regarding clinical outcomes in the PD patients who underwent subthalamic nucleus DBS implantation, comparing the preoperative off-medication condition with the off-medication/on-stimulation condition 1 year after the surgery in both procedure groups, there was a mean 47.8% ± 9.5% improvement in the Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) score in the simultaneous group, while the sequential group experienced 47.5% ± 15.8% improvement (p = 0.96). Moreover, a marked reduction in the levodopa-equivalent dose from preoperatively to postoperatively was similar in these 2 groups. The simultaneous bilateral procedure presented major advantages over the traditional sequential approach, with a shorter total operating time. CONCLUSIONS A simultaneous stereotactic approach significantly reduces the operation time in bilateral DBS procedures, resulting in decreased microrecording time, contributing to the optimization of functional

  6. Framework for a low-cost intra-operative image-guided neuronavigator including brain shift compensation.

    Science.gov (United States)

    Bucki, M; Lobos, C; Payan, Y

    2007-01-01

    In this paper we present a methodology to address the problem of brain tissue deformation referred to as 'brain-shift'. This deformation occurs throughout a neurosurgery intervention and strongly alters the accuracy of the neuronavigation systems used to date in clinical routine which rely solely on pre-operative patient imaging to locate the surgical target, such as a tumour or a functional area. After a general description of the framework of our intra-operative image-guided system, we describe a procedure to generate patient specific finite element meshes of the brain and propose a biomechanical model which can take into account tissue deformations and surgical procedures that modify the brain structure, like tumour or tissue resection.

  7. Consciousness as a phenomenon in the operational architectonics of brain organization: Criticality and self-organization considerations

    International Nuclear Information System (INIS)

    Fingelkurts, Andrew A.; Fingelkurts, Alexander A.; Neves, Carlos F.H.

    2013-01-01

    In this paper we aim to show that phenomenal consciousness is realized by a particular level of brain operational organization and that understanding human consciousness requires a description of the laws of the immediately underlying neural collective phenomena, the nested hierarchy of electromagnetic fields of brain activity – operational architectonics. We argue that the subjective mental reality and the objective neurobiological reality, although seemingly worlds apart, are intimately connected along a unified metastable continuum and are both guided by the universal laws of the physical world such as criticality, self-organization and emergence

  8. The Vertebrate Brain, Evidence of Its Modular Organization and Operating System: Insights into the Brain's Basic Units of Structure, Function, and Operation and How They Influence Neuronal Signaling and Behavior

    Science.gov (United States)

    Baslow, Morris H.

    2011-01-01

    The human brain is a complex organ made up of neurons and several other cell types, and whose role is processing information for use in eliciting behaviors. However, the composition of its repeating cellular units for both structure and function are unresolved. Based on recent descriptions of the brain's physiological “operating system”, a function of the tri-cellular metabolism of N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) for supply of energy, and on the nature of “neuronal words and languages” for intercellular communication, insights into the brain's modular structural and functional units have been gained. In this article, it is proposed that the basic structural unit in brain is defined by its physiological operating system, and that it consists of a single neuron, and one or more astrocytes, oligodendrocytes, and vascular system endothelial cells. It is also proposed that the basic functional unit in the brain is defined by how neurons communicate, and consists of two neurons and their interconnecting dendritic–synaptic–dendritic field. Since a functional unit is composed of two neurons, it requires two structural units to form a functional unit. Thus, the brain can be envisioned as being made up of the three-dimensional stacking and intertwining of myriad structural units which results not only in its gross structure, but also in producing a uniform distribution of binary functional units. Since the physiological NAA–NAAG operating system for supply of energy is repeated in every structural unit, it is positioned to control global brain function. PMID:21720525

  9. Operant behavior to obtain palatable food modifies neuronal plasticity in the brain reward circuit.

    Science.gov (United States)

    Guegan, Thomas; Cutando, Laura; Ayuso, Eduard; Santini, Emanuela; Fisone, Gilberto; Bosch, Fatima; Martinez, Albert; Valjent, Emmanuel; Maldonado, Rafael; Martin, Miquel

    2013-02-01

    Palatability enhances food intake by hedonic mechanisms that prevail over caloric necessities. Different studies have demonstrated the role of endogenous cannabinoids in the mesocorticolimbic system in controlling food hedonic value and consumption. We hypothesize that the endogenous cannabinoid system could also be involved in the development of food-induced behavioral alterations, such as food-seeking and binge-eating, by a mechanism that requires neuroplastic changes in the brain reward pathway. For this purpose, we evaluated the role of the CB1 cannabinoid receptor (CB1-R) in the behavioral and neuroplastic changes induced by operant training for standard, highly caloric or highly palatable isocaloric food using different genetics, viral and pharmacological approaches. Neuroplasticity was evaluated by measuring changes in dendritic spine density in neurons previously labeled with the dye DiI. Only operant training to obtain highly palatable isocaloric food induced neuroplastic changes in neurons of the nucleus accumbens shell and prefrontal cortex that were associated to changes in food-seeking behavior. These behavioral and neuroplastic modifications induced by highly palatable isocaloric food were dependent on the activity of the CB1-R. Neuroplastic changes induced by highly palatable isocaloric food are similar to those produced by some drugs of abuse and may be crucial in the alteration of food-seeking behavior leading to overweight and obesity. Copyright © 2012 Elsevier B.V. and ECNP. All rights reserved.

  10. Operation of a P300-based brain-computer interface by patients with spinocerebellar ataxia

    Directory of Open Access Journals (Sweden)

    Yoji Okahara

    Full Text Available Objective: We investigated the efficacy of a P300-based brain-computer interface (BCI for patients with spinocerebellar ataxia (SCA, which is often accompanied by cerebellar impairment. Methods: Eight patients with SCA and eight age- and gender-matched healthy controls were instructed to input Japanese hiragana characters using the P300-based BCI with green/blue flicker. All patients depended on some assistance in their daily lives (modified Rankin scale: mean 3.5. The chief symptom was cerebellar ataxia; no cognitive deterioration was present. A region-based, two-step P300-based BCI was used. During the P300 task, eight-channel EEG data were recorded, and a linear discriminant analysis distinguished the target from other nontarget regions of the matrix. Results: The mean online accuracy in BCI operation was 82.9% for patients with SCA and 83.2% for controls; no significant difference was detected. Conclusion: The P300-based BCI was operated successfully not only by healthy controls but also by individuals with SCA. Significance: These results suggest that the P300-based BCI may be applicable for patients with SCA. Keywords: BCI, BMI, P300, Visual stimuli, Spinocerebellar ataxia

  11. The effect of dynamic operating conditions on nano-particle emissions from a light-duty diesel engine applicable to prime and auxiliary machines on marine vessels

    Directory of Open Access Journals (Sweden)

    Hyungmin Lee

    2012-12-01

    Full Text Available This study presents the nano-sized particle emission characteristics from a small turbocharged common rail diesel engine applicable to prime and auxiliary machines on marine vessels. The experiments were conducted under dynamic engine operating conditions, such as steady-state, cold start, and transient conditions. The particle number and size distributions were analyzed with a high resolution PM analyzer. The diesel oxidation catalyst (DOC had an insignificant effect on the reduction in particle number, but particle number emissions were drastically reduced by 3 to 4 orders of magnitude downstream of the diesel particulate filter (DPF at various steady conditions. Under high speed and load conditions, the particle filtering efficiency was decreased by the partial combustion of trapped particles inside the DPF because of the high exhaust temperature caused by the increased particle number concentration. Retarded fuel injection timing and higher EGR rates led to increased particle number emissions. As the temperature inside the DPF increased from 25 °C to 300 °C, the peak particle number level was reduced by 70% compared to cold start conditions. High levels of nucleation mode particle generation were found in the deceleration phases during the transient tests.

  12. The world of Nano

    International Nuclear Information System (INIS)

    Noh, Seung Jeong; Hyun, Jun Won; An, Yong Hyeon; Lee, Sung Uk; Jee, Hye Gu; Kim, Young Seon

    2006-07-01

    The contents of this book are the beginning of nano technology, definition of nano, commercialization of nano technology, prospect of nano technology, survive with nano t-, development strategy of n-t in the U.S, and Japan, Korea, and other countries, comparison of development strategy of n-t among each country, various measurement technology for practical n-t, scanning tunneling microscopy, nano device, carbon nano tube, nano belt and nano wire, application of sensor in daily life, energy, post-Genome period and using as medicine with nano bio technology.

  13. [Resting-state functional magnetic resonance study of brain function changes after TIPS operation in patients with liver cirrhosis].

    Science.gov (United States)

    Liu, C; Wang, H B; Yu, Y Q; Wang, M Q; Zhang, G B; Xu, L Y; Wu, J M

    2016-12-20

    Objective: To investigate the brain function changes in cirrhosis patients after transjugular intrahepatic portosystemic shunt (TIPS), resting-state functional MRI (rs-fMRI) performed and fractional amplitude of low frequency fluctuation (fALFF) was analyzed. Methods: From January 2014 to February 2016, a total of 96 cirrhotic patients from invasive technology department and infection department in the First Affiliated Hospital of Anhui Medical University were selected , the blood ammonia data of 96 cirrhotic patients with TIPS operation in four groups were collected after 1, 3, 6 and 12 month, and all subjects performed rs-fMRI scans. The rs-fMRI data processed with DPARSF and SPM12 softwares, whole-brain fALFF values were calculated, and One-Way analysis of variance , multiple comparison analysis and correlation analysis were performed. Results: There were brain regions with significant function changes in four groups patients with TIPS operation after 1, 3, 6 and 12 month, including bilateral superior temporal gyrus, right middle temportal gyrus , right hippocampus, right island of inferior frontal gyrus, left fusiform gyrus, left olfactory cortex, left orbital superior frontal gyrus (all P brain function areas increased in left olfactory cortex, left inferior temporal gyrus, left fusiform gyrus, left orbital middle frontal gyrus, left putamen, left cerebelum, and decreased in left lingual gyrus; patients in the 6-month follow-up showed that brain function areas increased in left middle temportal gyrus, right supramarginal gyrus, right temporal pole, right central operculum, and decreased in left top edge of angular gyrus, left postcentral gyrus; patients in the 12-month follow-up showed that brain function areas increased in right hippocampus, right middle cingulate gyrus, and decreased in right middle temportal gyrus.Compared with patients in the 3-month follow-up, patients in the 6-month follow-up showed that brain function areas increased in left superior

  14. Combining task-evoked and spontaneous activity to improve pre-operative brain mapping with fMRI

    Science.gov (United States)

    Fox, Michael D.; Qian, Tianyi; Madsen, Joseph R.; Wang, Danhong; Li, Meiling; Ge, Manling; Zuo, Huan-cong; Groppe, David M.; Mehta, Ashesh D.; Hong, Bo; Liu, Hesheng

    2016-01-01

    Noninvasive localization of brain function is used to understand and treat neurological disease, exemplified by pre-operative fMRI mapping prior to neurosurgical intervention. The principal approach for generating these maps relies on brain responses evoked by a task and, despite known limitations, has dominated clinical practice for over 20 years. Recently, pre-operative fMRI mapping based on correlations in spontaneous brain activity has been demonstrated, however this approach has its own limitations and has not seen widespread clinical use. Here we show that spontaneous and task-based mapping can be performed together using the same pre-operative fMRI data, provide complimentary information relevant for functional localization, and can be combined to improve identification of eloquent motor cortex. Accuracy, sensitivity, and specificity of our approach are quantified through comparison with electrical cortical stimulation mapping in eight patients with intractable epilepsy. Broad applicability and reproducibility of our approach is demonstrated through prospective replication in an independent dataset of six patients from a different center. In both cohorts and every individual patient, we see a significant improvement in signal to noise and mapping accuracy independent of threshold, quantified using receiver operating characteristic curves. Collectively, our results suggest that modifying the processing of fMRI data to incorporate both task-based and spontaneous activity significantly improves functional localization in pre-operative patients. Because this method requires no additional scan time or modification to conventional pre-operative data acquisition protocols it could have widespread utility. PMID:26408860

  15. Numerical determination of the amplification of a cylindrical proportional counter operating at low pressure. Application to nano-dosimetry

    International Nuclear Information System (INIS)

    Moutarde, Cyrille

    1994-01-01

    This work is devoted to a study of proportional counters used to measure the energy deposition in micrometer biological sites. Tissue equivalent gas filling improve typical operating mode of those counters. Specially, the extension of the multiplication zone becomes important at low pressures. A Monte Carlo simulation has been used to study the behaviour of an electron swarm in the sensitive volume. The calculations show that electrons are not in equilibrium with the applied electric field in this geometry. The influence of the gradient field and the rotation of the electrons around the anode wire has been studied carefully. The importance of non-equilibrium effects on the theoretical amplification calculated through the ionisation coefficient has been confirmed by experimental investigations. The statistical fluctuations of multiplication process has been calculated by the determination of avalanche spectra at the anode. Resolution of an ultra-miniature counter have been calculated to improve technological limitations of experimental nanodosimetry. (author) [fr

  16. Nano Fertilizers

    Directory of Open Access Journals (Sweden)

    Hatice DAĞHAN

    2017-06-01

    Full Text Available Agricultural land is decreasing day by day due to erosion, environmental pollution, unconscious irrigation and fertilization. On the other hand, it is necessary to increase agricultural production in order to meet the needs of the developing industry as well as the nutritional needs of the growing population. In the recent years, nano fertilizers have begun to be produced to obtain the highest amount and quality of production from the unit area. Previous research shows that nano fertilizers cause an increase in the use efficiency of plant nutrients, reduce soil toxicity, minimize the potential adverse effects of excessive chemical fertilizer use, and reduce fertilizer application frequency. Nano fertilizers are important in agriculture to increase crop yield and nutrient use efficiency, and to reduce excessive use ofchemical fertilizers. The most important properties of these fertilizers are that they contain one or more of macro and micronutrients, they can be applied frequently in small amounts and are environmentally friendly. However, when applied at high doses, they exhibit decreasing effects on plant growth and crop yields, similar to chemical fertilizers. In this review, the definition, importan ce, and classification of nano fertilizers, their application in plant production, advantages and disadvantages and the results obtained in this field were discussed.

  17. Volitional enhancement of firing synchrony and oscillation by neuronal operant conditioning: interaction with neurorehabilitation and brain-machine interface.

    Science.gov (United States)

    Sakurai, Yoshio; Song, Kichan; Tachibana, Shota; Takahashi, Susumu

    2014-01-01

    In this review, we focus on neuronal operant conditioning in which increments in neuronal activities are directly rewarded without behaviors. We discuss the potential of this approach to elucidate neuronal plasticity for enhancing specific brain functions and its interaction with the progress in neurorehabilitation and brain-machine interfaces. The key to-be-conditioned activities that this paper emphasizes are synchronous and oscillatory firings of multiple neurons that reflect activities of cell assemblies. First, we introduce certain well-known studies on neuronal operant conditioning in which conditioned enhancements of neuronal firing were reported in animals and humans. These studies demonstrated the feasibility of volitional control over neuronal activity. Second, we refer to the recent studies on operant conditioning of synchrony and oscillation of neuronal activities. In particular, we introduce a recent study showing volitional enhancement of oscillatory activity in monkey motor cortex and our study showing selective enhancement of firing synchrony of neighboring neurons in rat hippocampus. Third, we discuss the reasons for emphasizing firing synchrony and oscillation in neuronal operant conditioning, the main reason being that they reflect the activities of cell assemblies, which have been suggested to be basic neuronal codes representing information in the brain. Finally, we discuss the interaction of neuronal operant conditioning with neurorehabilitation and brain-machine interface (BMI). We argue that synchrony and oscillation of neuronal firing are the key activities required for developing both reliable neurorehabilitation and high-performance BMI. Further, we conclude that research of neuronal operant conditioning, neurorehabilitation, BMI, and system neuroscience will produce findings applicable to these interrelated fields, and neuronal synchrony and oscillation can be a common important bridge among all of them.

  18. Nano-bio-sensing

    CERN Document Server

    Carrara, Sandro

    2011-01-01

    This book examines state-of-the-art applications of nano-bio-sensing. It brings together researchers from nano-electronics and bio-technology, providing multidisciplinary content from nano-structures fabrication to bio-sensing applications.

  19. Combining task-evoked and spontaneous activity to improve pre-operative brain mapping with fMRI.

    Science.gov (United States)

    Fox, Michael D; Qian, Tianyi; Madsen, Joseph R; Wang, Danhong; Li, Meiling; Ge, Manling; Zuo, Huan-Cong; Groppe, David M; Mehta, Ashesh D; Hong, Bo; Liu, Hesheng

    2016-01-01

    Noninvasive localization of brain function is used to understand and treat neurological disease, exemplified by pre-operative fMRI mapping prior to neurosurgical intervention. The principal approach for generating these maps relies on brain responses evoked by a task and, despite known limitations, has dominated clinical practice for over 20years. Recently, pre-operative fMRI mapping based on correlations in spontaneous brain activity has been demonstrated, however this approach has its own limitations and has not seen widespread clinical use. Here we show that spontaneous and task-based mapping can be performed together using the same pre-operative fMRI data, provide complimentary information relevant for functional localization, and can be combined to improve identification of eloquent motor cortex. Accuracy, sensitivity, and specificity of our approach are quantified through comparison with electrical cortical stimulation mapping in eight patients with intractable epilepsy. Broad applicability and reproducibility of our approach are demonstrated through prospective replication in an independent dataset of six patients from a different center. In both cohorts and every individual patient, we see a significant improvement in signal to noise and mapping accuracy independent of threshold, quantified using receiver operating characteristic curves. Collectively, our results suggest that modifying the processing of fMRI data to incorporate both task-based and spontaneous activity significantly improves functional localization in pre-operative patients. Because this method requires no additional scan time or modification to conventional pre-operative data acquisition protocols it could have widespread utility. Copyright © 2015. Published by Elsevier Inc.

  20. Applying online nano-UHPLC to proteomics

    DEFF Research Database (Denmark)

    Falkenby, Lasse Gaarde; Hørning, Ole; Ravnsborg, Christian

    Ultra High Performance Liquid Chromatography (UHPLC) pushes the limits of feasible column designs by allowing higher operational pressure. Migrating from nano-HPLC to nano-UHPLC and coupling directly to a mass spectrometer requires alterations to the setup to allow the increase in pressure. We...

  1. Computation by symmetry operations in a structured model of the brain: Recognition of rotational invariance and time reversal

    Science.gov (United States)

    McGrann, John V.; Shaw, Gordon L.; Shenoy, Krishna V.; Leng, Xiaodan; Mathews, Robert B.

    1994-06-01

    Symmetries have long been recognized as a vital component of physical and biological systems. What we propose here is that symmetry operations are an important feature of higher brain function and result from the spatial and temporal modularity of the cortex. These symmetry operations arise naturally in the trion model of the cortex. The trion model is a highly structured mathematical realization of the Mountcastle organizational principle [Mountcastle, in The Mindful Brain (MIT, Cambridge, 1978)] in which the cortical column is the basic neural network of the cortex and is comprised of subunit minicolumns, which are idealized as trions with three levels of firing. A columnar network of a small number of trions has a large repertoire of quasistable, periodic spatial-temporal firing magic patterns (MP's), which can be excited. The MP's are related by specific symmetries: Spatial rotation, parity, ``spin'' reversal, and time reversal as well as other ``global'' symmetry operations in this abstract internal language of the brain. These MP's can be readily enhanced (as well as inherent categories of MP's) by only a small change in connection strengths via a Hebb learning rule. Learning introduces small breaking of the symmetries in the connectivities which enables a symmetry in the patterns to be recognized in the Monte Carlo evolution of the MP's. Examples of the recognition of rotational invariance and of a time-reversed pattern are presented. We propose the possibility of building a logic device from the hardware implementation of a higher level architecture of trion cortical columns.

  2. ``DMS-R, the Brain of the ISS'', 10 Years of Continuous Successful Operation in Space

    Science.gov (United States)

    Wolff, Bernd; Scheffers, Peter

    2012-08-01

    Space industries on both sides of the Atlantic were faced with a new situation of collaboration in the beginning of the 1990s.In 1995, industrial cooperation between ASTRIUM ST, Bremen and RSC-E, Moscow started aiming the outfitting of the Russian Service Module ZVEZDA for the ISS with computers. The requested equipments had to provide not only redundancy but fault tolerance and high availability. The design and development of two fault tolerant computers, (FTCs) responsible for the telemetry (Telemetry Computer: TC) and the central control (CC), as well as the man machine interface CPC were contracted to ASTRIUM ST, Bremen. The computer system is responsible e.g. for the life support system and the ISS re-boost control.In July 2000, the integration of the Russian Service Module ZVEZDA with Russian ZARYA FGB and American Node 1 bears witness for transatlantic and European cooperation.The Russian Service module ZVEZDA provides several basic functions as Avionics Control, the Environmental Control and Life Support (ECLS) in the ISS and control of the docked Automatic Transfer Vehicle (ATV) which includes re-boost of ISS. If these elementary functions fail or do not work reliable the effects for the ISS will be catastrophic with respect to Safety (manned space) and ISS mission.For that reason the responsible computer system Data Management System - Russia (DMS-R) is also called "The brain of the ISS".The Russian Service module ZVEZDA, including DMS-R, was launched on 12th of July, 2000. DMS-R was operational also during launch and docking.The talk provide information about the definition, design and development of DMS-R, the integration of DMS-R in the Russian Service module and the maintenance of the system in space. Besides the technical aspects are also the German - Russian cooperation an important subject of this speech. An outlook finalises the talk providing further development activities and application of fault tolerant systems.The importance of the DMS

  3. Synthesis of Boron Nano wires, Nano tubes, and Nano sheets

    International Nuclear Information System (INIS)

    Patel, R.B.; Chou, T.; Iqbal, Z.

    2014-01-01

    The synthesis of boron nano wires, nano tubes, and nano sheets using a thermal vapor deposition process is reported. This work confirms previous research and provides a new method capable of synthesizing boron nano materials. The materials were made by using various combinations of MgB 2 , Mg(BH 4 ) 2 , MCM-41, NiB, and Fe wire. Unlike previously reported methods, a nanoparticle catalyst and a silicate substrate are not required for synthesis. Two types of boron nano wires, boron nano tubes, and boron nano sheets were made. Their morphology and chemical composition were determined through the use of scanning electron microscopy, transmission electron microscopy, and electron energy loss spectroscopy. These boron-based materials have potential for electronic and hydrogen storage applications.

  4. Intra-operative cerebrospinal fluid sampling versus post-operative lumbar puncture for detection of leptomeningeal disease in malignant paediatric brain tumours.

    Directory of Open Access Journals (Sweden)

    Sharon Y Y Low

    Full Text Available Leptomeningeal disease is a feared sequelae of malignant paediatric brain tumours. Current methods for its detection is the combined use of cranio-spinal MRI, and CSF cytology from a post-operative lumbar puncture. In this study, the authors hypothesize that CSF taken at the start of surgery, either from an external ventricular drain or neuroendoscope will have equal sensitivity for positive tumour cells, in comparison to lumbar puncture. Secondary hypotheses include positive correlation between CSF cytology and MRI findings of LMD. From a clinical perspective, the key aim of the study was for affected paediatric patients to avoid an additional procedure of a lumbar puncture, often performed under anaesthesia after neurosurgical intervention.This is single-institution, retrospective study of paediatric patients diagnosed with malignant brain tumours. Its main aim was to compare cytological data from CSF collected at the time of surgery versus data from an interval lumbar puncture. In addition, MRI imaging of the same cohort of patients was examined for leptomeningeal disease and corroborated against CSF tumour cytology findings.Thirty patients are recruited for this study. Data analysis demonstrates a statistically significant association between our intra-operative CSF and LP sampling. Furthermore, our results also show for significant correlation between evidence of leptomeningeal disease on MRI findings versus intra-operative CSF positivity for tumour cells.Although this is a retrospective study with a limited population, our data concurs with potential to avoid an additional procedure for the paediatric patient diagnosed with a malignant brain tumour.

  5. Nano-technology and nano-toxicology

    OpenAIRE

    Maynard, Robert L.

    2012-01-01

    Rapid developments in nano-technology are likely to confer significant benefits on mankind. But, as with perhaps all new technologies, these benefits are likely to be accompanied by risks, perhaps by new risks. Nano-toxicology is developing in parallel with nano-technology and seeks to define the hazards and risks associated with nano-materials: only when risks have been identified they can be controlled. This article discusses the reasons for concern about the potential effects on health of ...

  6. ROC [Receiver Operating Characteristics] study of maximum likelihood estimator human brain image reconstructions in PET [Positron Emission Tomography] clinical practice

    International Nuclear Information System (INIS)

    Llacer, J.; Veklerov, E.; Nolan, D.; Grafton, S.T.; Mazziotta, J.C.; Hawkins, R.A.; Hoh, C.K.; Hoffman, E.J.

    1990-10-01

    This paper will report on the progress to date in carrying out Receiver Operating Characteristics (ROC) studies comparing Maximum Likelihood Estimator (MLE) and Filtered Backprojection (FBP) reconstructions of normal and abnormal human brain PET data in a clinical setting. A previous statistical study of reconstructions of the Hoffman brain phantom with real data indicated that the pixel-to-pixel standard deviation in feasible MLE images is approximately proportional to the square root of the number of counts in a region, as opposed to a standard deviation which is high and largely independent of the number of counts in FBP. A preliminary ROC study carried out with 10 non-medical observers performing a relatively simple detectability task indicates that, for the majority of observers, lower standard deviation translates itself into a statistically significant detectability advantage in MLE reconstructions. The initial results of ongoing tests with four experienced neurologists/nuclear medicine physicians are presented. Normal cases of 18 F -- fluorodeoxyglucose (FDG) cerebral metabolism studies and abnormal cases in which a variety of lesions have been introduced into normal data sets have been evaluated. We report on the results of reading the reconstructions of 90 data sets, each corresponding to a single brain slice. It has become apparent that the design of the study based on reading single brain slices is too insensitive and we propose a variation based on reading three consecutive slices at a time, rating only the center slice. 9 refs., 2 figs., 1 tab

  7. Optical Topography of Evoked Brain Activity during Mental Tasks Involving Whole Number Operations

    Science.gov (United States)

    Ortiz, Enrique

    2014-01-01

    Students start to memorize arithmetic facts from early elementary school mathematics activities. Their fluency or lack of fluency with these facts could affect their efforts as they carry out mental calculations as adults. This study investigated participants' levels of brain activation and possible reasons for these levels as they solved…

  8. Receiver operating characteristic analysis and its potential role in evaluating the effect of head movement in PET of the brain

    International Nuclear Information System (INIS)

    Patterson, H.; Clarke, G.H.; Lombardo, P.; McKay, W.J.; Austin and Repatriation Medical Centre, Heidelberg, VIC

    1999-01-01

    Full text: We outline an example of receiver operating characteristic (ROC) analysis in the assessment of image quality. ROC analysis is a measure of image quality that accounts for the consequences of the decision and the role of the observer. Kim and Haynie (Nuclear Diagnostic Imaging: Practical Clinical Applications. Melbourne: Macmillan, 1987) describe ROC analysis as an 'objective approach to the evaluation of diagnostic decision making'. ROC analysis is an ideal technique for evaluating images of a Hoffman brain phantom obtained using positron emission tomography. Images have been acquired with the phantom in different positions. The position of the phantom and the time the phantom remained in each position was based on the measurements of head movement during simulated brain imaging (Patterson et al., Technologists Symposium, ANZSNM, 1998). This study was undertaken to explore the potential of ROC analysis in determining the effect of movement on the ability to detect lesions of various sizes

  9. Nano-technology and nano-toxicology.

    Science.gov (United States)

    Maynard, Robert L

    2012-01-01

    Rapid developments in nano-technology are likely to confer significant benefits on mankind. But, as with perhaps all new technologies, these benefits are likely to be accompanied by risks, perhaps by new risks. Nano-toxicology is developing in parallel with nano-technology and seeks to define the hazards and risks associated with nano-materials: only when risks have been identified they can be controlled. This article discusses the reasons for concern about the potential effects on health of exposure to nano-materials and relates these to the evidence of the effects on health of the ambient aerosol. A number of hypotheses are proposed and the dangers of adopting unsubstantiated hypotheses are stressed. Nano-toxicology presents many challenges and will need substantial financial support if it is to develop at a rate sufficient to cope with developments in nano-technology.

  10. Nano cobalt oxides for photocatalytic hydrogen production

    KAUST Repository

    Mangrulkar, Priti A.; Joshi, Meenal M.; Tijare, Saumitra N.; Polshettiwar, Vivek; Labhsetwar, Nitin K.; Rayalu, Sadhana Suresh

    2012-01-01

    of various operating parameters in hydrogen generation by nano cobalt oxide was then studied in detail. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

  11. Nano dots and nano crystals detectors applications and questions

    International Nuclear Information System (INIS)

    Paltiel, Y.; Shusterman, S.; Naaman, R.; Aqua, T.; Banin, U.; Aharoni, A.

    2006-01-01

    Full Text: Nano technology is in the center of attention in the last decade. In our work we are using nano dots, nano crystals and quantum wells to study and fabricate infrared devices. In this study we aim to develop an accurate narrow band infrared sensor that will use quantum mechanics at room temperature. The sensor is based on a FET like structure, in which the current is very sensitive to potential changes on its surface. We have shown that this configuration provides flexibility and variability in operation bandgap and response. However, the relations between the quantum and the macroscopic world are not trivial and the coupling between worlds influences the transport, noise, and optical measurements. In this talk we will show some of the infrared devices we are studying, and try to present the rich physics and relations that combine between the two worlds

  12. A Link between the Increase in Electroencephalographic Coherence and Performance Improvement in Operating a Brain-Computer Interface

    Directory of Open Access Journals (Sweden)

    Irma Nayeli Angulo-Sherman

    2015-01-01

    Full Text Available We study the relationship between electroencephalographic (EEG coherence and accuracy in operating a brain-computer interface (BCI. In our case, the BCI is controlled through motor imagery. Hence, a number of volunteers were trained using different training paradigms: classical visual feedback, auditory stimulation, and functional electrical stimulation (FES. After each training session, the volunteers’ accuracy in operating the BCI was assessed, and the event-related coherence (ErCoh was calculated for all possible combinations of pairs of EEG sensors. After at least four training sessions, we searched for significant differences in accuracy and ErCoh using one-way analysis of variance (ANOVA and multiple comparison tests. Our results show that there exists a high correlation between an increase in ErCoh and performance improvement, and this effect is mainly localized in the centrofrontal and centroparietal brain regions for the case of our motor imagery task. This result has a direct implication with the development of new techniques to evaluate BCI performance and the process of selecting a feedback modality that better enhances the volunteer’s capacity to operate a BCI system.

  13. Tangible User Interface and Mu Rhythm Suppression: The Effect of User Interface on the Brain Activity in Its Operator and Observer

    Directory of Open Access Journals (Sweden)

    Kazuo Isoda

    2017-03-01

    Full Text Available The intuitiveness of tangible user interface (TUI is not only for its operator. It is quite possible that this type of user interface (UI can also have an effect on the experience and learning of observers who are just watching the operator using it. To understand the possible effect of TUI, the present study focused on the mu rhythm suppression in the sensorimotor area reflecting execution and observation of action, and investigated the brain activity both in its operator and observer. In the observer experiment, the effect of TUI on its observers was demonstrated through the brain activity. Although the effect of the grasping action itself was uncertain, the unpredictability of the result of the action seemed to have some effect on the mirror neuron system (MNS-related brain activity. In the operator experiment, in spite of the same grasping action, the brain activity was activated in the sensorimotor area when UI functions were included (TUI. Such activation of the brain activity was not found with a graphical user interface (GUI that has UI functions without grasping action. These results suggest that the MNS-related brain activity is involved in the effect of TUI, indicating the possibility of UI evaluation based on brain activity.

  14. Hypofractionated stereotactic radiotherapy in five daily fractions for post-operative surgical cavities in brain metastases patients with and without prior whole brain radiation.

    Science.gov (United States)

    Al-Omair, Ameen; Soliman, Hany; Xu, Wei; Karotki, Aliaksandr; Mainprize, Todd; Phan, Nicolas; Das, Sunit; Keith, Julia; Yeung, Robert; Perry, James; Tsao, May; Sahgal, Arjun

    2013-12-01

    Our purpose was to report efficacy of hypofractionated cavity stereotactic radiotherapy (HCSRT) in patients with and without prior whole brain radiotherapy (WBRT). 32 surgical cavities in 30 patients (20 patients/21 cavities had no prior WBRT and 10 patients/11 cavities had prior WBRT) were treated with image-guided linac stereotactic radiotherapy. 7 of the 10 prior WBRT patients had "resistant" local disease given prior surgery, post-operative WBRT and a re-operation, followed by salvage HCSRT. The clinical target volume was the post-surgical cavity, and a 2-mm margin applied as planning target volume. The median total dose was 30 Gy (range: 25-37.5 Gy) in 5 fractions. In the no prior and prior WBRT cohorts, the median follow-up was 9.7 months (range: 3.0-23.6) and 15.3 months (range: 2.9-39.7), the median survival was 23.6 months and 39.7 months, and the 1-year cavity local recurrence progression- free survival (LRFS) was 79 and 100%, respectively. At 18 months the LRFS dropped to 29% in the prior WBRT cohort. Grade 3 radiation necrosis occurred in 3 prior WBRT patients. We report favorable outcomes with HCSRT, and well selected patients with prior WBRT and "resistant" disease may have an extended survival favoring aggressive salvage HCSRT at a moderate risk of radiation necrosis.

  15. Store-Operated Calcium Entries Control Neural Stem Cell Self-Renewal in the Adult Brain Subventricular Zone.

    Science.gov (United States)

    Domenichini, Florence; Terrié, Elodie; Arnault, Patricia; Harnois, Thomas; Magaud, Christophe; Bois, Patrick; Constantin, Bruno; Coronas, Valérie

    2018-05-01

    The subventricular zone (SVZ) is the major stem cell niche in the brain of adult mammals. Within this region, neural stem cells (NSC) proliferate, self-renew and give birth to neurons and glial cells. Previous studies underlined enrichment in calcium signaling-related transcripts in adult NSC. Because of their ability to mobilize sustained calcium influxes in response to a wide range of extracellular factors, store-operated channels (SOC) appear to be, among calcium channels, relevant candidates to induce calcium signaling in NSC whose cellular activities are continuously adapted to physiological signals from the microenvironment. By Reverse Transcription Polymerase Chain Reaction (RT-PCR), Western blotting and immunocytochemistry experiments, we demonstrate that SVZ cells express molecular actors known to build up SOC, namely transient receptor potential canonical 1 (TRPC1) and Orai1, as well as their activator stromal interaction molecule 1 (STIM1). Calcium imaging reveals that SVZ cells display store-operated calcium entries. Pharmacological blockade of SOC with SKF-96365 or YM-58483 (also called BTP2) decreases proliferation, impairs self-renewal by shifting the type of SVZ stem cell division from symmetric proliferative to asymmetric, thereby reducing the stem cell population. Brain section immunostainings show that TRPC1, Orai1, and STIM1 are expressed in vivo, in SOX2-positive SVZ NSC. Injection of SKF-96365 in brain lateral ventricle diminishes SVZ cell proliferation and reduces the ability of SVZ cells to form neurospheres in vitro. The present study combining in vitro and in vivo approaches uncovers a major role for SOC in the control of SVZ NSC population and opens new fields of investigation for stem cell biology in health and disease. Stem Cells 2018;36:761-774. © AlphaMed Press 2018.

  16. Critical Care Air Transport Team severe traumatic brain injury short-term outcomes during flight for Operation Iraqi Freedom/Operation Enduring Freedom.

    Science.gov (United States)

    Boyd, L Renee; Borawski, J; Lairet, J; Limkakeng, A T

    2017-10-01

    Our understanding of the expertise and equipment required to air transport injured soldiers with severe traumatic brain injuries (TBIs) continue to evolve. We conducted a retrospective chart review of characteristics, interventions required and short-term outcomes of patients with severe TBI managed by the US Air Force Critical Care Air Transport Teams (CCATTs) deployed in support of Operation Iraqi Freedom and Operation Enduring Freedom between 1 June 2007 and 31 August 2010. Patients were cared for based on guidelines given by the Brain Trauma Foundation and the Joint Theater Trauma System by non-neurosurgeon physicians with dedicated neurocritical care training. We report basic characteristics, injuries, interventions required and complications during transport. Intracranial haemorrhage was the most common diagnosis in this cohort. Most injuries were weapon related. During this study, there were no reported in-flight deaths. The majority of patients were mechanically ventilated. There were 45 patients who required at least one vasopressor to maintain adequate tissue perfusion, including four patients who required three or more. Some patients required intracranial pressure (ICP) management, treatment of diabetes insipidus and/or seizure prophylaxis medications. Air transport personnel must be prepared to provide standard critical care but also care specific to TBIs, including ICP control and management of diabetes insipidus. Although these patients and their potential complications are traditionally managed by neurosurgeons, those providers without neurosurgical backgrounds can be provided this training to help fill a wartime need. This study provides data for the future development of air transport guidelines for validating and clearing flight surgeons. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. Nano cobalt oxides for photocatalytic hydrogen production

    KAUST Repository

    Mangrulkar, Priti A.

    2012-07-01

    Nano structured metal oxides including TiO 2, Co 3O 4 and Fe 3O 4 have been synthesized and evaluated for their photocatalytic activity for hydrogen generation. The photocatalytic activity of nano cobalt oxide was then compared with two other nano structured metal oxides namely TiO 2 and Fe 3O 4. The synthesized nano cobalt oxide was characterized thoroughly with respect to EDX and TEM. The yield of hydrogen was observed to be 900, 2000 and 8275 mmol h -1 g -1 of photocatalyst for TiO 2, Co 3O 4 and Fe 3O 4 respectively under visible light. It was observed that the hydrogen yield in case of nano cobalt oxide was more than twice to that of TiO 2 and the hydrogen yield of nano Fe 3O 4 was nearly four times as compared to nano Co 3O 4. The influence of various operating parameters in hydrogen generation by nano cobalt oxide was then studied in detail. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

  18. Physics of the Brain. Prevention of the Epileptic Seizures by the Multi-photon Pulsed-operated Fiber Lasers in the Ultraviolet Range of Frequencies.

    Science.gov (United States)

    Stefan, V. Alexander; IAPS Team

    The novel study of the epileptogenesis mechanisms is proposed. It is based on the pulsed-operated (amplitude modulation) multi-photon (frequency modulation) fiber-laser interaction with the brain epilepsy-topion (the epilepsy onset area), so as to prevent the excessive electrical discharge (epileptic seizure) in the brain. The repetition frequency, Ω, matches the low frequency (epileptic) phonon waves in the brain. The laser repetition frequency (5-100 pulses per second) enables the resonance-scanning of the wide range of the phonon (possible epileptic-to-be) activity in the brain. The tunable fiber laser frequencies, Δω (multi photon operation), are in the ultraviolet frequency range, thus enabling monitoring of the electrical charge imbalance (within the 10s of milliseconds), and the DNA-corruption in the epilepsy-topion, as the possible cause of the disease. Supported by Nikola Tesla Labs., Stefan University.

  19. Nano devices and sensors

    CERN Document Server

    Liaw, Shien-Kuei; Chung, Yung-Hui

    2016-01-01

    This volume on semiconductor devices focuses on such topics as nano-imprinting, lithography, nanowire charge-trapping, thermo-stability in nanowires, nano-electrodes, and voltage and materials used for fabricating and improving electrical characteristics of nano-materials.

  20. From Nano Structure to Systems: Fabrication and Characterization

    International Nuclear Information System (INIS)

    Uda Hashim

    2011-01-01

    NPD is designed in various nano wires scale size from 100 nm down to 20 nm. Next, the nano fabrication process flow development which consists of the detailed parameters and recipes are developed for nano wires formation. In order to produce very small nano wires, the dimensions, developments, etch profiles of nano wires and size reduction by thermal oxidation was investigated. Finally, the combination on top-down nano fabrication method and size-reduction has resulted in successful reduction of Nano wires reduced from 100 nm to approximately 20 nm. Spacer Patterning Lithography (SPL) is another technique used to fabricate nano structure especially nano wire. It is a low-cost and compatible to standard CMOS fabrication process. SPL, in general is a combination of conventional photolithography, anisotropic etchings and the excellent homogeneity and reproducibility of conformal chemical vapor deposition processes. The detail process flow involving every step in SPL including the deposition of a sacrificial layer, the definition of vertical step by means of lithography and etch-back process, the deposition of a conformal layer, final anisotropic etching and formation of gold pad. A wire with the scale in nano size has a wide range of applications. Up to present, the nano wires have been implemented in electronics, optics, mechanics, and sensing technology etc. One of the fields where nano wires have been used as building blocks is biosensor. Biosensor has been developed for different applications such as health care, industrial process control, environmental monitoring, quality control of food applications etc. Nevertheless, the conventional biosensor has its disadvantages, which are expensive, time-consuming, and require highly trained personnel. Therefore, there is increasing interest in the development of new type of biosensor which has the advantages of label-free, ultrasensitive, and near real-time operation. (author)

  1. Manipulation of isolated brain nerve terminals by an external magnetic field using D-mannose-coated γ-Fe2O3 nano-sized particles and assessment of their effects on glutamate transport.

    Science.gov (United States)

    Borisova, Tatiana; Krisanova, Natalia; Borуsov, Arsenii; Sivko, Roman; Ostapchenko, Ludmila; Babic, Michal; Horak, Daniel

    2014-01-01

    The manipulation of brain nerve terminals by an external magnetic field promises breakthroughs in nano-neurotechnology. D-Mannose-coated superparamagnetic nanoparticles were synthesized by coprecipitation of Fe(II) and Fe(III) salts followed by oxidation with sodium hypochlorite and addition of D-mannose. Effects of D-mannose-coated superparamagnetic maghemite (γ-Fe2O3) nanoparticles on key characteristics of the glutamatergic neurotransmission were analysed. Using radiolabeled L-[(14)C]glutamate, it was shown that D-mannose-coated γ-Fe2O3 nanoparticles did not affect high-affinity Na(+)-dependent uptake, tonic release and the extracellular level of L-[(14)C]glutamate in isolated rat brain nerve terminals (synaptosomes). Also, the membrane potential of synaptosomes and acidification of synaptic vesicles was not changed as a result of the application of D-mannose-coated γ-Fe2O3 nanoparticles. This was demonstrated with the potential-sensitive fluorescent dye rhodamine 6G and the pH-sensitive dye acridine orange. The study also focused on the analysis of the potential use of these nanoparticles for manipulation of nerve terminals by an external magnetic field. It was shown that more than 84.3 ± 5.0% of L-[(14)C]glutamate-loaded synaptosomes (1 mg of protein/mL) incubated for 5 min with D-mannose-coated γ-Fe2O3 nanoparticles (250 µg/mL) moved to an area, in which the magnet (250 mT, gradient 5.5 Т/m) was applied compared to 33.5 ± 3.0% of the control and 48.6 ± 3.0% of samples that were treated with uncoated nanoparticles. Therefore, isolated brain nerve terminals can be easily manipulated by an external magnetic field using D-mannose-coated γ-Fe2O3 nanoparticles, while the key characteristics of glutamatergic neurotransmission are not affected. In other words, functionally active synaptosomes labeled with D-mannose-coated γ-Fe2O3 nanoparticles were obtained.

  2. Long-Term Neurobehavioral Symptoms and Return to Productivity in Operation Enduring Freedom/Operation Iraqi Freedom Veterans With and Without Traumatic Brain Injury.

    Science.gov (United States)

    Mortera, Marianne H; Kinirons, Stacy A; Simantov, Jessie; Klingbeil, Heidi

    2018-02-01

    To describe Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) veterans who underwent the Comprehensive Traumatic Brain Injury Evaluation (CTBIE), differences between the traumatic brain injury (TBI) and non-TBI subgroups, and factors associated with return to productivity (RTP). Retrospective medical record review. Medical center. Medical records of OEF/OIF veterans (N=236) who underwent the CTBIE between 2009 and 2013. Not applicable. Demographic characteristics, injury history, clinical presentation, and factors associated with RTP. Veteran sample included 90.7% men, was 45.3% white and 34.7% black, with half of Hispanic origin, and had a mean age of 33 years. The mean time since injury was approximately 4 years. Reported symptoms were high, with >90% reporting anxiousness, irritability, sleep difficulty, forgetfulness, and headaches. TBI diagnosis was found in 163 veterans (69%). The TBI subgroup was younger (TBI: 32.5y vs non-TBI: 34.9y; P=.02), reported a greater number of injuries (P<.001), and had significantly higher rates of half of the reported symptoms. Greatest differences were noted with forgetfulness (TBI: 95.7% vs non-TBI: 79.5%; P<.001), poor concentration (TBI: 90.2% vs non-TBI: 76.7%; P=.007), and headaches (TBI: 93.9% vs non-TBI: 83.6%; P=.014). RTP was 60.6% for the total veteran population. Factors associated with RTP were race (white) (odds ratio [OR], 2.00; 95% confidence interval [CI], 1.13-3.55; P=.018), sensitivity to light (OR, 2.58; 95% CI, 1.17-5.66; P=.018), and fatigue (OR, 3.68; 95% CI, 1.51-8.95; P=.004). Veterans that did RTP were 3 times less likely to report depression (OR, .32; 95% CI, .12-.85; P=.022). Veterans reported a substantial number of lingering symptoms, with a higher prevalence in veterans with TBI. Veterans with reported depression were less likely to RTP. Future research should focus on the relation between depression and non-RTP and the effectiveness of Department of Veterans Affairs services. Copyright

  3. HNF - Helmholtz Nano Facility

    Directory of Open Access Journals (Sweden)

    Wolfgang Albrecht

    2017-05-01

    Full Text Available The Helmholtz Nano Facility (HNF is a state-of-the-art cleanroom facility. The cleanroom has ~1100 m2 with cleanroom classes of DIN ISO 1-3. HNF operates according to VDI DIN 2083, Good Manufacturing Practice (GMP and aquivalent to Semiconductor Industry Association (SIA standards. HNF is a user facility of Forschungszentrum Jülich and comprises a network of facilities, processes and systems for research, production and characterization of micro- and nanostructures. HNF meets the basic supply of micro- and nanostructures for nanoelectronics, fluidics. micromechanics, biology, neutron and energy science, etc.. The task of HNF is rapid progress in nanostructures and their technology, offering efficient access to infrastructure and equipment. HNF gives access to expertise and provides resources in production, synthesis, characterization and integration of structures, devices and circuits. HNF covers the range from basic research to application oriented research facilitating a broad variety of different materials and different sample sizes.

  4. Nano-optomechanical transducer

    Science.gov (United States)

    Rakich, Peter T; El-Kady, Ihab F; Olsson, Roy H; Su, Mehmet Fatih; Reinke, Charles; Camacho, Ryan; Wang, Zheng; Davids, Paul

    2013-12-03

    A nano-optomechanical transducer provides ultrabroadband coherent optomechanical transduction based on Mach-wave emission that uses enhanced photon-phonon coupling efficiencies by low impedance effective phononic medium, both electrostriction and radiation pressure to boost and tailor optomechanical forces, and highly dispersive electromagnetic modes that amplify both electrostriction and radiation pressure. The optomechanical transducer provides a large operating bandwidth and high efficiency while simultaneously having a small size and minimal power consumption, enabling a host of transformative phonon and signal processing capabilities. These capabilities include optomechanical transduction via pulsed phonon emission and up-conversion, broadband stimulated phonon emission and amplification, picosecond pulsed phonon lasers, broadband phononic modulators, and ultrahigh bandwidth true time delay and signal processing technologies.

  5. Contributions to Executive Dysfunction in Operation Enduring Freedom/Operation Iraqi Freedom Veterans With Posttraumatic Stress Disorder and History of Mild Traumatic Brain Injury.

    Science.gov (United States)

    Jurick, Sarah M; Crocker, Laura D; Sanderson-Cimino, Mark; Keller, Amber V; Trenova, Liljana S; Boyd, Briana L; Twamley, Elizabeth W; Rodgers, Carie S; Schiehser, Dawn M; Aupperle, Robin L; Jak, Amy J

    Posttraumatic stress disorder (PTSD), history of mild traumatic brain injury (mTBI), and executive function (EF) difficulties are prevalent in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) Veterans. We evaluated the contributions of injury variables, lower-order cognitive component processes (processing speed/attention), and psychological symptoms to EF. OEF/OIF Veterans (N = 65) with PTSD and history of mTBI were administered neuropsychological tests of EF and self-report assessments of PTSD and depression. Those impaired on one or more EF measures had higher PTSD and depression symptoms and lower processing speed/attention performance than those with intact performance on all EF measures. Across participants, poorer attention/processing speed performance and higher psychological symptoms were associated with worse performance on specific aspects of EF (eg, inhibition and switching) even after accounting for injury variables. Although direct relationships between EF and injury variables were equivocal, there was an interaction between measures of injury burden and processing speed/attention such that those with greater injury burden exhibited significant and positive relationships between processing speed/attention and inhibition/switching, whereas those with lower injury burden did not. Psychological symptoms as well as lower-order component processes of EF (attention and processing speed) contribute significantly to executive dysfunction in OEF/OIF Veterans with PTSD and history of mTBI. However, there may be equivocal relationships between injury variables and EF that warrant further study. Results provide groundwork for more fully understanding cognitive symptoms in OEF/OIF Veterans with PTSD and history of mTBI that can inform psychological and cognitive interventions in this population.

  6. Accessing the nanostructural analysis network organisation (NANO)

    International Nuclear Information System (INIS)

    Hicks, R.; Ringer, S.

    2003-01-01

    Full text: As a Major National Research Facility (MNRF), NANO unites five Australian microscopy and microanalysis centres to form the peak Australian facility for nanometric analysis of the structure and chemistry of materials. NANO is headquartered at the Australian Key Centre for Microscopy and Microanalysis at the University of Sydney and involves the Centres for Microscopy and Microanalysis at the Universities of Queensland and Western Australia, the Electron Microscope Unit at the University of New South Wales and the Microanalytical Research Centre at the University of Melbourne. Together these major centres maintain a wide range of complementary instrumentation for the characterisation of nanostructure. NANO links them into a co-ordinated national facility with unified charges and booking systems. The facility will provide open access to a wide range of present and future partners involving local and international linkages. For this reason, NANO is designed to allow the incorporation of other groups as additional nodes. All Australian researchers are eligible to apply for support to use NANO through the Travel and Access Program (NANO-TAP), which will support basic travel and accommodation costs as well as instrument time. Access to the national grid may involve on-site presence at a particular node or remote telemicroscopy. Both passive (observation) and active (operation) modes of telemicroscopy are available. This presentation will address the NANO-TAP application procedure, the use of remote telemicroscopy and the formation of additional nodes. Copyright (2003) Australian Microbeam Analysis Society

  7. Nano Mechanical Machining Using AFM Probe

    Science.gov (United States)

    Mostofa, Md. Golam

    Complex miniaturized components with high form accuracy will play key roles in the future development of many products, as they provide portability, disposability, lower material consumption in production, low power consumption during operation, lower sample requirements for testing, and higher heat transfer due to their very high surface-to-volume ratio. Given the high market demand for such micro and nano featured components, different manufacturing methods have been developed for their fabrication. Some of the common technologies in micro/nano fabrication are photolithography, electron beam lithography, X-ray lithography and other semiconductor processing techniques. Although these methods are capable of fabricating micro/nano structures with a resolution of less than a few nanometers, some of the shortcomings associated with these methods, such as high production costs for customized products, limited material choices, necessitate the development of other fabricating techniques. Micro/nano mechanical machining, such an atomic force microscope (AFM) probe based nano fabrication, has, therefore, been used to overcome some the major restrictions of the traditional processes. This technique removes material from the workpiece by engaging micro/nano size cutting tool (i.e. AFM probe) and is applicable on a wider range of materials compared to the photolithographic process. In spite of the unique benefits of nano mechanical machining, there are also some challenges with this technique, since the scale is reduced, such as size effects, burr formations, chip adhesions, fragility of tools and tool wear. Moreover, AFM based machining does not have any rotational movement, which makes fabrication of 3D features more difficult. Thus, vibration-assisted machining is introduced into AFM probe based nano mechanical machining to overcome the limitations associated with the conventional AFM probe based scratching method. Vibration-assisted machining reduced the cutting forces

  8. Operant conditioning of a multiple degree-of-freedom brain-machine interface in a primate model of amputation.

    Science.gov (United States)

    Balasubramanian, Karthikeyan; Southerland, Joshua; Vaidya, Mukta; Qian, Kai; Eleryan, Ahmed; Fagg, Andrew H; Sluzky, Marc; Oweiss, Karim; Hatsopoulos, Nicholas

    2013-01-01

    Operant conditioning with biofeedback has been shown to be an effective method to modify neural activity to generate goal-directed actions in a brain-machine interface. It is particularly useful when neural activity cannot be mathematically mapped to motor actions of the actual body such as in the case of amputation. Here, we implement an operant conditioning approach with visual feedback in which an amputated monkey is trained to control a multiple degree-of-freedom robot to perform a reach-to-grasp behavior. A key innovation is that each controlled dimension represents a behaviorally relevant synergy among a set of joint degrees-of-freedom. We present a number of behavioral metrics by which to assess improvements in BMI control with exposure to the system. The use of non-human primates with chronic amputation is arguably the most clinically-relevant model of human amputation that could have direct implications for developing a neural prosthesis to treat humans with missing upper limbs.

  9. Heart rate calculation from ensemble brain wave using wavelet and Teager-Kaiser energy operator.

    Science.gov (United States)

    Srinivasan, Jayaraman; Adithya, V

    2015-01-01

    Electroencephalogram (EEG) signal artifacts are caused by various factors, such as, Electro-oculogram (EOG), Electromyogram (EMG), Electrocardiogram (ECG), movement artifact and line interference. The relatively high electrical energy cardiac activity causes EEG artifacts. In EEG signal processing the general approach is to remove the ECG signal. In this paper, we introduce an automated method to extract the ECG signal from EEG using wavelet and Teager-Kaiser energy operator for R-peak enhancement and detection. From the detected R-peaks the heart rate (HR) is calculated for clinical diagnosis. To check the efficiency of our method, we compare the HR calculated from ECG signal recorded in synchronous with EEG. The proposed method yields a mean error of 1.4% for the heart rate and 1.7% for mean R-R interval. The result illustrates that, proposed method can be used for ECG extraction from single channel EEG and used in clinical diagnosis like estimation for stress analysis, fatigue, and sleep stages classification studies as a multi-model system. In addition, this method eliminates the dependence of additional synchronous ECG in extraction of ECG from EEG signal process.

  10. Laser-Bioplasma Interaction: Excitation and Suppression of the Brain Waves by the Multi-photon Pulsed-operated Fiber Lasers in the Ultraviolet Range of Frequencies

    Science.gov (United States)

    Stefan, V. Alexander; IAPS-team Team

    2017-10-01

    The novel study of the laser excitation-suppression of the brain waves is proposed. It is based on the pulsed-operated multi-photon fiber-laser interaction with the brain parvalbumin (PV) neurons. The repetition frequency matches the low frequency brain waves (5-100 Hz); enabling the resonance-scanning of the wide range of the PV neurons (the generators of the brain wave activity). The tunable fiber laser frequencies are in the ultraviolet frequency range, thus enabling the monitoring of the PV neuron-DNA, within the 10s of milliseconds. In medicine, the method can be used as an ``instantaneous-on-off anesthetic.'' Supported by Nikola Tesla Labs, Stefan University.

  11. Energy challenge and nano-sciences

    International Nuclear Information System (INIS)

    Romulus, Anne-Marie; Chamelot, Pierre; Chaudret, Bruno; Comtat, Maurice; Fajerwerg, Katia; Philippot, Karine; Geoffron, Patrice; Lacroix, Jean-Christophe; Abanades, Stephane; Flamant, Gilles; HUERTA-ORTEGA, Benjamin; Cezac, Pierre; Lincot, Daniel; Roncali, Jean; Artero, Vincent; GuiLLET, Nicolas; Fauvarque, Jean-Francois; Simon, Patrice; Taberna, Pierre-Louis

    2013-01-01

    This book first describes the role of energy in the development of nano-sciences, discusses energy needs, the perception of nano-sciences by societies as far as the energy challenge is concerned, describes the contribution of nano-catalyzers to energy and how these catalyzers are prepared. A second part addresses the new perspectives regarding carbon: production of biofuels from biomass, process involved in CO 2 geological storage, improvement of solar fuel production with the use of nano-powders. The third part describes the new orientations of solar energy: contribution of the thin-layer inorganic sector to photovoltaic conversion, perspectives for organic photovoltaic cells, operation of new dye-sensitized nanocrystalline solar cells. The fourth part addresses the hydrogen sector: credibility, contribution of biomass in hydrogen production, production of hydrogen by electrochemistry, new catalyzers for electrolyzers and fuel cells. The last part address improved electrochemical reactors

  12. Book Review: Nano physics & Nano technology

    Directory of Open Access Journals (Sweden)

    Abdolkhaled Zaree

    2012-12-01

    Full Text Available During last decades, there are a lot of emphases on studying material behavior in atomic scale. In most scientific and engineering fields, one can see the effect of nanotechnology. The aim of nanoscience is to design and fabrication of new and applicable materials. Nowadays, Nano is a popular science which chemists, physicist, doctors, engineers, financial managers and environment's fans for creating a good life via nanoscience have a great cooperation with each others. Materials in nano scale such as nanotubes and nanowires have extraordinary properties which by optimization of these properties in nano scale and then develop these properties to macro scale, they've been challenging issues. For instance, materials in nano scale improve mechanical properties of polymers and metallic materials via nano particles and on the other hand by producing a thin film on surfaces improve surface hardening. Besides, nanotechnology is in hi-tech industries such as magnetic devices, surface coating, and biomaterial, material having sensors, polymers, gels, ceramics and intelligent membrane. Nano-carbon tubes are considered intelligent due to the fact that they couple electrochemical and elastic properties simultaneously, hence have greater activation energy density in comparison with other intelligent materials. Studying nanoscience is important because it causes the life to be better. Future Materials and structures will have a lot of outstanding properties. Intelligent machines can repair, recycle and reconstruct themselves. All these features are only possible in nano zone. Nano in engineering science can provide the possibility of making light missiles for exploring space. The reduced weight can be achieved by replacing traditional materials with hybrid nanocomposites.

  13. Language and motor function thresholds during pediatric extra-operative electrical cortical stimulation brain mapping.

    Science.gov (United States)

    Zea Vera, Alonso; Aungaroon, Gewalin; Horn, Paul S; Byars, Anna W; Greiner, Hansel M; Tenney, Jeffrey R; Arthur, Todd M; Crone, Nathan E; Holland, Katherine D; Mangano, Francesco T; Arya, Ravindra

    2017-10-01

    To examine current thresholds and their determinants for language and motor mapping with extra-operative electrical cortical stimulation (ECS). ECS electrocorticograph recordings were reviewed to determine functional thresholds. Predictors of functional thresholds were found with multivariable analyses. In 122 patients (age 11.9±5.4years), average minimum, frontal, and temporal language thresholds were 7.4 (± 3.0), 7.8 (± 3.0), and 7.4 (± 3.1) mA respectively. Average minimum, face, upper and lower extremity motor thresholds were 5.4 (± 2.8), 6.1 (± 2.8), 4.9 (± 2.3), and 5.3 (± 3.3) mA respectively. Functional and after-discharge (AD)/seizure thresholds were significantly related. Minimum, frontal, and temporal language thresholds were higher than AD thresholds at all ages. Minimum motor threshold was higher than minimum AD threshold up to 8.0years of age, face motor threshold was higher than frontal AD threshold up to 11.8years age, and lower subsequently. UE motor thresholds remained below frontal AD thresholds throughout the age range. Functional thresholds are frequently above AD thresholds in younger children. These findings raise concerns about safety and neurophysiologic validity of ECS mapping. Functional and AD/seizure thresholds relationships suggest individual differences in cortical excitability which cannot be explained by clinical variables. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  14. The nano-science of C60 molecule

    International Nuclear Information System (INIS)

    Rafii-Tabar, H.

    2002-01-01

    Over the past few years, nano-science and its associated nano-technology have emerged into prominence in research institutions across the world. They have brought about new scientific and engineering paradigms, allowing for the manipulation of single atoms and molecules, designing and fabricating new materials, atom-by-atom, and devices that operate on significantly reduced time and length scales. One important area of research in nano-science and nano technology is carbon-based physics in the form of fullerene physics. The C 6 0 molecule, and other cage-like fullerenes, together with carbon nano tubes provide objects that can be combined to generate three-dimensional functional structures for use in the anticipated nano-technology of future. The unique properties of C 6 0 can also be exploited in designing nano-phase thin films with applications in nano-scope device technology and processes such as nano-lithography. This requires a deep understanding of the highly complex process of adsorption of this molecule on a variety of substrates. We review the field of nano-scale nucleation and growth of C 6 0 molecules on some of the technologically important substrates. In addition to experimental results, the results of a set of highly accurate computational simulations are also reported

  15. Brain-mind dyad, human experience, the consciousness tetrad and lattice of mental operations: and further, the need to integrate knowledge from diverse disciplines.

    Science.gov (United States)

    Singh, Ajai R; Singh, Shakuntala A

    2011-01-01

    Brain, Mind and Consciousness are the research concerns of psychiatrists, psychologists, neurologists, cognitive neuroscientists and philosophers. All of them are working in different and important ways to understand the workings of the brain, the mysteries of the mind and to grasp that elusive concept called consciousness. Although they are all justified in forwarding their respective researches, it is also necessary to integrate these diverse appearing understandings and try and get a comprehensive perspective that is, hopefully, more than the sum of their parts. There is also the need to understand what each one is doing, and by the other, to understand each other's basic and fundamental ideological and foundational underpinnings. This must be followed by a comprehensive and critical dialogue between the respective disciplines. Moreover, the concept of mind and consciousness in Indian thought needs careful delineation and critical/evidential enquiry to make it internationally relevant. The brain-mind dyad must be understood, with brain as the structural correlate of the mind, and mind as the functional correlate of the brain. To understand human experience, we need a triad of external environment, internal environment and a consciousness that makes sense of both. We need to evolve a consensus on the definition of consciousness, for which a working definition in the form of a Consciousness Tetrad of Default, Aware, Operational and Evolved Consciousness is presented. It is equally necessary to understand the connection between physical changes in the brain and mental operations, and thereby untangle and comprehend the lattice of mental operations. Interdisciplinary work and knowledge sharing, in an atmosphere of healthy give and take of ideas, and with a view to understand the significance of each other's work, and also to critically evaluate the present corpus of knowledge from these diverse appearing fields, and then carry forward from there in a spirit of

  16. Operation Brain Trauma Therapy

    Science.gov (United States)

    2012-10-01

    mouth, following the roof of the mouth, and advanced into the esophagus and toward the stomach. After the tube is passed to the correct length...cells inhibits lipopolysaccharide-stimulated tumor necrosis factor-alpha release by reducing calcium-dependent activation of nuclear-factor-kappaB

  17. The Nano Solar Case

    DEFF Research Database (Denmark)

    Hollensen, Svend; Lindgren, Peter

    2011-01-01

    ISO PAINT Nordic A/S produces roof coatings, facade painting as well as specialised products for surface treatments. The company decided that they would develop a nano solar ICT based project having the capacity to change the whole cost structure of a building, for example by a nano roof coating...

  18. Evaluating X-ray absorption of nano-bismuth oxide ointment for decreasing risks associated with X-ray exposure among operating room personnel and radiology experts

    Directory of Open Access Journals (Sweden)

    M. Rashidi

    2015-12-01

      Conclusion: It seems that due to higher atomic number and lower toxicity, Bi2O3 nanoparticles have better efficiency in X-ray absorbtion, comparing to the lead. Cream and ointment of bismuth oxide nanoparticles can be used as X-ray absorbant for different professions such as physicians, dentists, radiology experts, and operating room staff and consequently increase health and safety of these employees.

  19. The nano-science of C sub 6 0 molecule

    CERN Document Server

    Rafii-Tabar, H

    2002-01-01

    Over the past few years, nano-science and its associated nano-technology have emerged into prominence in research institutions across the world. They have brought about new scientific and engineering paradigms, allowing for the manipulation of single atoms and molecules, designing and fabricating new materials, atom-by-atom, and devices that operate on significantly reduced time and length scales. One important area of research in nano-science and nano technology is carbon-based physics in the form of fullerene physics. The C sub 6 0 molecule, and other cage-like fullerenes, together with carbon nano tubes provide objects that can be combined to generate three-dimensional functional structures for use in the anticipated nano-technology of future. The unique properties of C sub 6 0 can also be exploited in designing nano-phase thin films with applications in nano-scope device technology and processes such as nano-lithography. This requires a deep understanding of the highly complex process of adsorption of thi...

  20. Carbon nano tubes embedded in polymer nano fibers

    International Nuclear Information System (INIS)

    Dror, Y.; Kedem, S.; Khalfin, R.L.; Paz, Y.; Cohenl, Y.; Salalha, Y.; Yarin, A.L.; Zussman, A.

    2004-01-01

    Full Text: The electro spinning process was used successfully to embed Multi-walled carbon nano tubes (MWCNTs) and single-walled carbon nano tubes (SWCNTs) in a matrix of poly(ethylene oxide) (PEO) forming composite nano fibers. Initial dispersion of SWCNTs in water was achieved by the use of an amphphilic alternating copolymer of styrene and sodium maleate. MWNT dispersion was achieved by ionic and nonionic surfactants. The distribution and conformation of the nano tubes in the nano fibers were studied by transmission electron microscopy (TEM). Oxygen plasma etching was used to expose the nano tubes within the nano fibers to facilitate direct observation. Nano tube alignment within the nano fibers was shown to depend strongly on the quality of the initial dispersions. Well-dispersed and separated nano tubes were embedded in a straight and aligned form while entangled non-separated nano tubes were incorporated as dense aggregates. X-ray diffraction demonstrated a high degree of orientation of the PEO crystals in the electro spun nano fibers with embedded SWCNTs, whereas incorporation of MVCNTs had a detrimental effect on the polymer orientation. Composite polymer nano fibers containing dispersed phases of nanometric TiO 2 particles and MWCNTs were also prepared electro spinning. In this case, the polymer matrix was poly(acrylonitrile) (PAN). The morphology and possible applications of these composite nano fibers will be discussed

  1. NanoAODs

    CERN Document Server

    Husova, Lucia Anna

    2017-01-01

    The scientist on LHC experiment analyse a huge amount of data every day on the Grid. Thus new methods are requested, how to make the analysis more efficient. The NanoAOD is a derived dataset from AOD, where only information necessary for the analysis is stored. Thus the analysis can be more than two times faster, because of the smaller file size, which can be read faster on the Grid. The main goal of this summer student project was to help other users to start using NanoAODs by rewriting their user tasks. Two example users tasks were converted to NanoAODs and tested with the local train test. A speed up of 3.5 was reached. The results of the analysis tasks are identical independent if they use AODs or NanoAODs.

  2. Nano-composite materials

    Science.gov (United States)

    Lee, Se-Hee; Tracy, C. Edwin; Pitts, J. Roland

    2010-05-25

    Nano-composite materials are disclosed. An exemplary method of producing a nano-composite material may comprise co-sputtering a transition metal and a refractory metal in a reactive atmosphere. The method may also comprise co-depositing a transition metal and a refractory metal composite structure on a substrate. The method may further comprise thermally annealing the deposited transition metal and refractory metal composite structure in a reactive atmosphere.

  3. Optiske nano-fibre

    DEFF Research Database (Denmark)

    Rubahn, Horst-Günter; Simonsen, Adam Cohen

    2003-01-01

    Forskere ved Syddansk Universitet har udviklet organiske nano-aggregater, som gør det muligt under meget kontrollerede forhold at studere optiske fænomener på skalaer mindre end lysets bølgelængde.......Forskere ved Syddansk Universitet har udviklet organiske nano-aggregater, som gør det muligt under meget kontrollerede forhold at studere optiske fænomener på skalaer mindre end lysets bølgelængde....

  4. Cancer Nano medicine

    International Nuclear Information System (INIS)

    Li, H.; Pike, M.M.; Luo, X.; Liu, L.H.

    2013-01-01

    Bioengineered nano materials have inspired revolutionary imaging and drug delivery methods whose clinical application in cancer research has resulted in powerful medical devices for early diagnosis, treatment, and prevention of cancer. Recent advances in super imaging agents have resulted in improved resolution and sensitivity. For instance, fluorescent quantum dots with wavelength-tunable emissions, plasmon-resonant gold nano structures with shape-controlled near-infrared absorptions, and MRI-active iron oxide nanoparticles are well-established molecular imaging probes for noninvasive cancer imaging. Nano materials are also considered to be the most effective vectors that can break through transport bio barriers and deliver a constant dose of multiple therapeutic agents to tumors and intracellular endocytic compartments for cancer gene therapy, immunotherapy, or chemotherapy. Furthermore, nano wire- or nano tube-based electronic devices demonstrate extraordinary sensitivity capable of detection at the single molecule or protein level. It is anticipated that developing nano technology-driven imaging, sensing, and therapeutic systems will dramatically advance cancer research and clinical treatments.

  5. Evidence that the tri-cellular metabolism of N-acetylaspartate functions as the brain's "operating system": how NAA metabolism supports meaningful intercellular frequency-encoded communications.

    Science.gov (United States)

    Baslow, Morris H

    2010-11-01

    N-acetylaspartate (NAA), an acetylated derivative of L-aspartate (Asp), and N-acetylaspartylglutamate (NAAG), a derivative of NAA and L-glutamate (Glu), are synthesized by neurons in brain. However, neurons cannot catabolize either of these substances, and so their metabolism requires the participation of two other cell types. Neurons release both NAA and NAAG to extra-cellular fluid (ECF) upon stimulation, where astrocytes, the target cells for NAAG, hydrolyze it releasing NAA back into ECF, and oligodendrocytes, the target cells for NAA, hydrolyze it releasing Asp to ECF for recycling to neurons. This sequence is unique as it is the only known amino acid metabolic cycle in brain that requires three cell types for its completion. The results of this cycling are two-fold. First, neuronal metabolic water is transported to ECF for its removal from brain. Second, the rate of neuronal activity is coupled with focal hyperemia, providing stimulated neurons with the energy required for transmission of meaningful frequency-encoded messages. In this paper, it is proposed that the tri-cellular metabolism of NAA functions as the "operating system" of the brain, and is essential for normal cognitive and motor activities. Evidence in support of this hypothesis is provided by the outcomes of two human inborn errors in NAA metabolism.

  6. Modification by oxazepam of the diurnal variations in brain 125I-melatonin binding sites in sham-operated and pinealectomized rats

    International Nuclear Information System (INIS)

    Anis, Y.; Zisapel, N.; Nir, I.; Schmidt, U.

    1992-01-01

    Sham-operated and pinealectomized male rats were maintained at 14 h light: 10 h dark cycles (lights-on 5.00 h) and injected daily, for 14 days, with oxazepam or vehicle. 125 I-melatonin binding was recorded in synaptosomes prepared at 10.00, 18.00, and 24.00 h from the hypothalamus, hippocampus and medulla-pons of the rats. In the sham-operated, vehicle treated rats, specific 125 I-melatonin binding in all brain areas studied was higher at 18.00 h, whereas in the oxazepam-treated animals, binding was higher at 24.00 h than at the other times tested. In the pinealectomized, vehicle-treated rats, the binding recorded at 18.00 h in all three brain areas, was lower than at the other times of day tested. Oxazepam treatment decreased 125 I-melatonin binding at 24.00 h in the hippocampus and medulla-pons of the pinealectomized rats and did not significantly affect the binding in the hypothalamus. These results indicate the ability of oxazepam, pinealectomy and their combination, to manipulate the diurnal variations in 125 I-melatonin binding sites in the rat brain

  7. Brain Hyper-Connectivity and Operation-Specific Deficits during Arithmetic Problem Solving in Children with Developmental Dyscalculia

    Science.gov (United States)

    Rosenberg-Lee, Miriam; Ashkenazi, Sarit; Chen, Tianwen; Young, Christina B.; Geary, David C.; Menon, Vinod

    2015-01-01

    Developmental dyscalculia (DD) is marked by specific deficits in processing numerical and mathematical information despite normal intelligence (IQ) and reading ability. We examined how brain circuits used by young children with DD to solve simple addition and subtraction problems differ from those used by typically developing (TD) children who…

  8. ON NANO Λg-CLOSED SETS

    OpenAIRE

    Rajasekaran, Ilangovan; Nethaji, Ochanan

    2017-01-01

    Abstaract−In this paper, we introduce nano ∧g-closed sets in nano topological spaces. Some properties of nano ∧g-closed sets and nano ∧g-open sets are weaker forms of nano closed sets and nano open sets

  9. Novel plasmon nano-lasers

    NARCIS (Netherlands)

    Hill, M.T.; Marell, M.J.H.

    2010-01-01

    We will discuss some of the latest developments in metallic and plasmonic nano-lasers. Furthermore we will present our latest results on further miniaturization of electrically pumped plasmonic nano-lasers and also DFB Plasmon mode devices.

  10. Nano lasers in photonic VLSI

    NARCIS (Netherlands)

    Hill, M.T.; Oei, Y.S.; Smit, M.K.

    2007-01-01

    We examine the use of micro and nano lasers to form digital photonic VLSI building blocks. Problems such as isolation and cascading of building blocks are addressed, and the potential of future nano lasers explored.

  11. Applications of Nano-optics.

    Science.gov (United States)

    Zhou, Changhe; Fainman, Yeshaiahu; Sheng, Yunlong

    2011-11-01

    As nanoscale fabrication techniques advance, nano-optics continues to offer enabling solutions to numerous practical applications for information optics. This Applied Optics feature issue focuses on the Application of Nano-optics. © 2011 Optical Society of America

  12. Environmental silicate nano-biocomposites

    CERN Document Server

    Pollet, Eric

    2012-01-01

    Environmental Silicate Nano-Biocomposites focuses on nano-biocomposites, which are obtained by the association of silicates such as bioclays with biopolymers. By highlighting recent developments and findings, green and biodegradable nano-composites from both renewable and biodegradable polymers are explored. This includes coverage of potential markets such as packaging, agricultures, leisure and the fast food industry. The knowledge and experience of more than twenty international experts in diverse fields, from chemical and biochemical engineering to applications, is brought together in four different sections covering: Biodegradable polymers and Silicates, Clay/Polyesters Nano-biocomposites, Clay/Agropolymers Nano-biocomposites, and Applications and biodegradation of Nano-biocomposites. By exploring the relationships between the biopolymer structures, the processes, and the final properties Environmental Silicate Nano-Biocomposites explains how to design nano-materials to develop new, valuable, environmenta...

  13. Framework and Bio-Mechanical Model for a Per-Operative Image-Guided Neuronavigator Including 'Brain-Shift' Compensation

    OpenAIRE

    Bucki, Marek; Payan, Yohan

    2006-01-01

    2nd Workshop on Computer Assisted Diagnosis and Surgery, March 2006, Santiago de Chile; In this paper we present a methodology to adress the problem of brain tissue deformation referred to as "brainshift". This deformation occurs throughout a neurosurgery intervention and strongly alters the accuracy of the neuronavigation systems used to date in clinical routine which rely solely on preoperative patient imaging to locate the surgical target, such as a tumour or a functional area. After a gen...

  14. Appearance and impact of post-operative intracranial clips and coils on whole-brain CT angiography and perfusion

    International Nuclear Information System (INIS)

    Roach, Cayce J.; Russell, Cheryl L.; Hanson, Eric H.; Bluett, Brent; Orrison, William W.

    2012-01-01

    Background: To evaluate the effect of vascular clips and endovascular coils placed for intracranial aneurysms and arteriovenous malformations on whole-brain computed tomography (CT) angiography and perfusion. Methods: A 320-detector row dynamic volume CT system imaged 11 patients following surgical placement of vascular clips or endovascular coils. The extent of clip and coil subtraction by automated software was evaluated using CT digital subtraction angiography and CT perfusion. Impact on CT perfusion values by retained intracranial devices was compared to age- and gender-matched controls. Results: Clip and coil subtraction on CT angiography was graded as good in 8 and moderate in 3 cases. A residual neck and additional aneurysm were noted in 1 of 11 patients. Post-procedural axial slice level CT perfusion values decreased in reliability with increasing proximity to the metallic devices secondary to beam hardening. However, the intracranial devices did not affect axial slice level CTP values of cerebral blood volume, cerebral blood flow and mean transit time outside of the level of the device. Time to peak values was globally decreased outside of the immediate vascular intervention region. Conclusions: Advances in CT technology have provided clinically useful subtraction of intracranial clips and coils. While CT perfusion values were altered in device subtraction areas and within beam hardening artifact areas; they can provide valuable postoperative information on whole-brain hemodynamics. In selected cases, the combination of CT angiography and whole-brain CT perfusion can offer an alternative to conventional angiography that is a more invasive option.

  15. Identifying non-toxic doses of manganese for manganese-enhanced magnetic resonance imaging to map brain areas activated by operant behavior in trained rats.

    Science.gov (United States)

    Gálosi, Rita; Szalay, Csaba; Aradi, Mihály; Perlaki, Gábor; Pál, József; Steier, Roy; Lénárd, László; Karádi, Zoltán

    2017-04-01

    Manganese-enhanced magnetic resonance imaging (MEMRI) offers unique advantages such as studying brain activation in freely moving rats, but its usefulness has not been previously evaluated during operant behavior training. Manganese in a form of MnCl 2 , at a dose of 20mg/kg, was intraperitoneally infused. The administration was repeated and separated by 24h to reach the dose of 40mg/kg or 60mg/kg, respectively. Hepatotoxicity of the MnCl 2 was evaluated by determining serum aspartate aminotransferase, alanine aminotransferase, total bilirubin, albumin and protein levels. Neurological examination was also carried out. The animals were tested in visual cue discriminated operant task. Imaging was performed using a 3T clinical MR scanner. T1 values were determined before and after MnCl 2 administrations. Manganese-enhanced images of each animal were subtracted from their baseline images to calculate decrease in the T1 value (ΔT1) voxel by voxel. The subtracted T1 maps of trained animals performing visual cue discriminated operant task, and those of naive rats were compared. The dose of 60mg/kg MnCl 2 showed hepatotoxic effect, but even these animals did not exhibit neurological symptoms. The dose of 20 and 40mg/kg MnCl 2 increased the number of omissions and did not affect the accuracy of performing the visual cue discriminated operant task. Using the accumulated dose of 40mg/kg, voxels with a significant enhanced ΔT1 value were detected in the following brain areas of the visual cue discriminated operant behavior performed animals compared to those in the controls: the visual, somatosensory, motor and premotor cortices, the insula, cingulate, ectorhinal, entorhinal, perirhinal and piriform cortices, hippocampus, amygdala with amygdalohippocampal areas, dorsal striatum, nucleus accumbens core, substantia nigra, and retrorubral field. In conclusion, the MEMRI proved to be a reliable method to accomplish brain activity mapping in correlation with the operant behavior

  16. ACCELERATING NANO-TECHNOLOGICAL

    DEFF Research Database (Denmark)

    Jensen, Jens Stissing; Koch, Christian

    2007-01-01

    By viewing the construction industry as a technological innovation system (TIS) this paper discusses possible initiatives to accelerate nanotechnological innovations. The point of departure is a recent report on the application of nano-technology in the Danish construction industry, which concludes...... of the system are furthermore poorly equipped at identifying potentials within high-tech areas. In order to exploit the potentials of nano-technology it is thus argued that an alternative TIS needs to be established. Initiatives should identify and support “incubation rooms” or marked niches in order...

  17. Nano-electromembrane extraction

    DEFF Research Database (Denmark)

    Payán, María D Ramos; Li, Bin; Petersen, Nickolaj J.

    2013-01-01

    as extraction selectivity. Compared with conventional EME, the acceptor phase volume in nano-EME was down-scaled by a factor of more than 1000. This resulted in a very high enrichment capacity. With loperamide as an example, an enrichment factor exceeding 500 was obtained in only 5 min of extraction...... electrophoresis (CE). In that way the sample preparation performed by nano-EME was coupled directly with a CE separation. Separation performance of 42,000-193,000 theoretical plates could easily be obtained by this direct sample preparation and injection technique that both provided enrichment as well...

  18. Bio-inspired nano tools for neuroscience.

    Science.gov (United States)

    Das, Suradip; Carnicer-Lombarte, Alejandro; Fawcett, James W; Bora, Utpal

    2016-07-01

    Research and treatment in the nervous system is challenged by many physiological barriers posing a major hurdle for neurologists. The CNS is protected by a formidable blood brain barrier (BBB) which limits surgical, therapeutic and diagnostic interventions. The hostile environment created by reactive astrocytes in the CNS along with the limited regeneration capacity of the PNS makes functional recovery after tissue damage difficult and inefficient. Nanomaterials have the unique ability to interface with neural tissue in the nano-scale and are capable of influencing the function of a single neuron. The ability of nanoparticles to transcend the BBB through surface modifications has been exploited in various neuro-imaging techniques and for targeted drug delivery. The tunable topography of nanofibers provides accurate spatio-temporal guidance to regenerating axons. This review is an attempt to comprehend the progress in understanding the obstacles posed by the complex physiology of the nervous system and the innovations in design and fabrication of advanced nanomaterials drawing inspiration from natural phenomenon. We also discuss the development of nanomaterials for use in Neuro-diagnostics, Neuro-therapy and the fabrication of advanced nano-devices for use in opto-electronic and ultrasensitive electrophysiological applications. The energy efficient and parallel computing ability of the human brain has inspired the design of advanced nanotechnology based computational systems. However, extensive use of nanomaterials in neuroscience also raises serious toxicity issues as well as ethical concerns regarding nano implants in the brain. In conclusion we summarize these challenges and provide an insight into the huge potential of nanotechnology platforms in neuroscience. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Alterations in autobiographical memory for a blast event in Operation Enduring Freedom and Operation Iraqi Freedom veterans with mild traumatic brain injury.

    Science.gov (United States)

    Palombo, Daniela J; Kapson, Heather S; Lafleche, Ginette; Vasterling, Jennifer J; Marx, Brian P; Franz, Molly; Verfaellie, Mieke

    2015-07-01

    Although loss of consciousness associated with moderate or severe traumatic brain injury (TBI) is thought to interfere with encoding of the TBI event, little is known about the effects of mild TBI (mTBI), which typically involves only transient disruption in consciousness. Blast-exposed Afghanistan and Iraq War veterans were asked to recall the blast event. Participants were stratified based on whether the blast was associated with probable mTBI (n = 50) or not (n = 25). Narratives were scored for organizational structure (i.e., coherence) using the Narrative Coherence Coding Scheme (Reese et al., 2011) and episodic recollection using the Autobiographical Interview Coding Procedures (Levine et al., 2002). The mTBI group produced narratives that were less coherent but contained more episodic details than those of the no-TBI group. These results suggest that mTBI interferes with the organizational quality of memory in a manner that is independent of episodic detail generation. (c) 2015 APA, all rights reserved).

  20. Artificial neuron operations and spike-timing-dependent plasticity using memristive devices for brain-inspired computing

    Science.gov (United States)

    Marukame, Takao; Nishi, Yoshifumi; Yasuda, Shin-ichi; Tanamoto, Tetsufumi

    2018-04-01

    The use of memristive devices for creating artificial neurons is promising for brain-inspired computing from the viewpoints of computation architecture and learning protocol. We present an energy-efficient multiplier accumulator based on a memristive array architecture incorporating both analog and digital circuitries. The analog circuitry is used to full advantage for neural networks, as demonstrated by the spike-timing-dependent plasticity (STDP) in fabricated AlO x /TiO x -based metal-oxide memristive devices. STDP protocols for controlling periodic analog resistance with long-range stability were experimentally verified using a variety of voltage amplitudes and spike timings.

  1. Light‐driven Nano­‐robotics - Invited Plenary Presentation, IEEE NANO 2016

    DEFF Research Database (Denmark)

    Glückstad, Jesper

    ) and pioneering their use in so-called lightdriven nano-robotics. Hence, the aim of our latest R&D is to combine advanced topology optimisation, 3D printing of functionalized materials and light manipulation to demonstrate a structure-mediated micro-tonano coupling paradigm for controlled operation of robotic...... tools overcoming the diffraction limit while still being optically visible and manoeuvrable. 2PP-fabrication can already today create intricate nano-features merged onto larger microstructures that, in turn, are steerable by dynamic light beams. Applying multiple independently controllable laser beam...... traps on these structures will enable real-time light-driven nanorobotics with six-degrees-of-freedom. This sets the stage for new discoveries using calibrated steering of optimally shaped and functionalized nano-tools at the subcellular level and in full 3D - not available in the scientifi c world...

  2. NanoLaunch

    Science.gov (United States)

    Jones, Jonathan; Harris, Lawanna

    2015-01-01

    NASA's NanoLaunch effort will provide the framework to mature both Earth-to-orbit and on-orbit propulsion and avionics technologies while also providing affordable, dedicated access to low-Earth orbit for CubeSat-class payloads. The project will also serve as an early career personnel training opportunity with mentors to gain hands-on project experience.

  3. Editorial Emerging Multifunctional Nano structures

    International Nuclear Information System (INIS)

    Fan, H.; Lu, Y.; Ramanath, G.; Pomposo, J.A.

    2009-01-01

    The interest in emerging nano structures is growing exponentially since they are promising building blocks for advanced multifunctional nano composites. In recent years, an evolution from the controlled synthesis of individual monodisperse nanoparticles to the tailored preparation of hybrid spherical and also unsymmetrical multiparticle nano structures is clearly observed. As a matter of fact, the field of nano structures built around a nano species such as inside, outside, and next to a nanoparticle is becoming a new evolving area of research and development with potential applications in improved drug delivery systems, innovative magnetic devices, biosensors, and highly efficient catalysts, among several others Emerging nano structures with improved magnetic, conducting and smart characteristics are currently based on the design, synthesis, characterization and modeling of multifunctional nano object-based materials. In fact, core-shell nanoparticles and other related complex nano architectures covering a broad spectrum of materials (from metal and metal oxide to fused carbon, synthetic polymer, and bio polymer structures) to nano structure morphologies (spherical, cylindrical, star-like, etc.) are becoming the main building blocks for next generation of drug delivery systems, advanced sensors and biosensors, or improved nano composites. The five papers presented in this special issue examine the preparation and characterization of emerging multifunctional materials, covering from hybrid asymmetric structures to engineering nano composites.

  4. Superconducting nano-strip particle detectors

    International Nuclear Information System (INIS)

    Cristiano, R; Ejrnaes, M; Casaburi, A; Zen, N; Ohkubo, M

    2015-01-01

    We review progress in the development and applications of superconducting nano-strip particle detectors. Particle detectors based on superconducting nano-strips stem from the parent devices developed for single photon detection (SSPD) and share with them ultra-fast response times (sub-nanosecond) and the ability to operate at a relatively high temperature (2–5 K) compared with other cryogenic detectors. SSPDs have been used in the detection of electrons, neutral and charged ions, and biological macromolecules; nevertheless, the development of superconducting nano-strip particle detectors has mainly been driven by their use in time-of-flight mass spectrometers (TOF-MSs) where the goal of 100% efficiency at large mass values can be achieved. Special emphasis will be given to this case, reporting on the great progress which has been achieved and which permits us to overcome the limitations of existing mass spectrometers represented by low detection efficiency at large masses and charge/mass ambiguity. Furthermore, such progress could represent a breakthrough in the field. In this review article we will introduce the device concept and detection principle, stressing the peculiarities of the nano-strip particle detector as well as its similarities with photon detectors. The development of parallel strip configuration is introduced and extensively discussed, since it has contributed to the significant progress of TOF-MS applications. (paper)

  5. Radiation induced nano structures

    International Nuclear Information System (INIS)

    Ibragimova, E.M.; Kalanov, M.U.; Khakimov, Z.

    2006-01-01

    Full text: Nanometer-size silicon clusters have been attracting much attention due to their technological importance, in particular, as promising building blocks for nano electronic and nano photonic systems. Particularly, silicon wires are of great of interest since they have potential for use in one-dimensional quantum wire high-speed field effect transistors and light-emitting devices with extremely low power consumption. Carbon and metal nano structures are studied very intensely due to wide possible applications. Radiation material sciences have been dealing with sub-micron objects for a long time. Under interaction of high energy particles and ionizing radiation with solids by elastic and inelastic mechanisms, at first point defects are created, then they form clusters, column defects, disordered regions (amorphous colloids) and finally precipitates of another crystal phase in the matrix. Such irradiation induced evolution of structure defects and phase transformations was observed by X-diffraction techniques in dielectric crystals of quartz and corundum, which exist in and crystal modifications. If there is no polymorphism, like in alkali halide crystals, then due to radiolysis halogen atoms are evaporated from the surface that results in non-stoichiometry or accumulated in the pores formed by metal vacancies in the sub-surface layer. Nano-pores are created by intensive high energy particles irradiation at first chaotically and then they are ordered and in part filled by inert gas. It is well-known mechanism of radiation induced swelling and embrittlement of metals and alloys, which is undesirable for construction materials for nuclear reactors. Possible solution of this problem may come from nano-structured materials, where there is neither swelling nor embrittlement at gas absorption due to very low density of the structure, while strength keeps high. This review considers experimental observations of radiation induced nano-inclusions in insulating

  6. After-discharges and seizures during pediatric extra-operative electrical cortical stimulation functional brain mapping: Incidence, thresholds, and determinants.

    Science.gov (United States)

    Aungaroon, Gewalin; Zea Vera, Alonso; Horn, Paul S; Byars, Anna W; Greiner, Hansel M; Tenney, Jeffrey R; Arthur, Todd M; Crone, Nathan E; Holland, Katherine D; Mangano, Francesco T; Arya, Ravindra

    2017-10-01

    This study examined the incidence, thresholds, and determinants of electrical cortical stimulation (ECS)-induced after-discharges (ADs) and seizures. Electrocorticograph recordings were reviewed to determine incidence of ECS-induced ADs and seizures. Multivariable analyses for predictors of AD/seizure occurrence and their thresholds were performed. In 122 patients, the incidence of ADs and seizures was 77% (94/122) and 35% (43/122) respectively. Males (odds ratio [OR] 2.92, 95% CI 1.21-7.38, p=0.02) and MRI-negative patients (OR 3.69, 95% CI 1.24-13.7, p=0.03) were found to have higher odds of ECS-induced ADs. A significant trend for decreasing AD thresholds with age was seen (regression co-efficient -0.151, 95% CI -0.267 to -0.035, p=0.011). ECS-induced seizures were more likely in patients with lateralized functional imaging (OR 6.62, 95% CI 1.36-55.56, p=0.036, for positron emission tomography) and presence of ADs (OR 3.50, 95% CI 1.12-13.36, p=0.043). ECS is associated with a high incidence of ADs and seizures. With age, current thresholds decrease and the probability for AD/seizure occurrence increases. ADs and seizures during ECS brain mapping are potentially hazardous and affect its functional validity. Thus, safer method(s) for brain mapping with improved neurophysiologic validity are desirable. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  7. Nano semiconducting materials

    CERN Document Server

    Saravanan, R

    2016-01-01

    The main focus of the present book is the characterization of a number of nano-semiconducting materials, using such techniques as powder X-ray diffraction, UV-visible spectrophotometry, Raman spectrometry, scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometry. The materials studied include ZnS, TiO2, NiO, Ga doped ZnO, Mn doped SnO2, Mn doped CeO2 and Mn doped ZrO2.

  8. Combinatorial Nano-Bio Interfaces.

    Science.gov (United States)

    Cai, Pingqiang; Zhang, Xiaoqian; Wang, Ming; Wu, Yun-Long; Chen, Xiaodong

    2018-06-08

    Nano-bio interfaces are emerging from the convergence of engineered nanomaterials and biological entities. Despite rapid growth, clinical translation of biomedical nanomaterials is heavily compromised by the lack of comprehensive understanding of biophysicochemical interactions at nano-bio interfaces. In the past decade, a few investigations have adopted a combinatorial approach toward decoding nano-bio interfaces. Combinatorial nano-bio interfaces comprise the design of nanocombinatorial libraries and high-throughput bioevaluation. In this Perspective, we address challenges in combinatorial nano-bio interfaces and call for multiparametric nanocombinatorics (composition, morphology, mechanics, surface chemistry), multiscale bioevaluation (biomolecules, organelles, cells, tissues/organs), and the recruitment of computational modeling and artificial intelligence. Leveraging combinatorial nano-bio interfaces will shed light on precision nanomedicine and its potential applications.

  9. Nano materials for Energy and Environmental Applications

    International Nuclear Information System (INIS)

    Srinivasan, S.; Kannan, A.M.; Kothurkar, N.; Khalil, Y.; Kuravi, S.

    2015-01-01

    Nano materials enabled technologies have been seamlessly integrated into applications such as aviation and space, chemical industry, optics, solar hydrogen, fuel cell, batteries, sensors, power generation, aeronautic industry, building/construction industry, automotive engineering, consumer electronics, thermoelectric devices, pharmaceuticals, and cosmetic industry. Clean energy and environmental applications often demand the development of novel nano materials that can provide shortest reaction pathways for the enhancement of reaction kinetics. Understanding the physicochemical, structural, microstructural, surface, and interface properties of nano materials is vital for achieving the required efficiency, cycle life, and sustain ability in various technological applications. Nano materials with specific size and shape such as nano tubes, nano fibers/nano wires, nano cones, nano composites, nano rods, nano islands, nanoparticles, nanospheres, and nano shells to provide unique properties can be synthesized by tuning the process conditions.

  10. Long-Term Evaluation of Changes in Operative Technique and Hardware-Related Complications With Deep Brain Stimulation.

    Science.gov (United States)

    Falowski, Steven M; Ooi, Yinn Cher; Bakay, Roy A E

    2015-12-01

    Deep brain stimulation is the most frequent neurosurgical procedure for movement disorders. While this elective procedure carries a low-risk profile, it is not free of complications. As a new procedure, the pattern of complications changed with experience and modification of surgical technique and equipment. This review analyzes the most common hardware-related complications that may occur and techniques to avoid them. It is a retrospective review of 432 patients undergoing 1077 procedures over a 14-year period by one surgeon with emphasis on the analysis of surgical technique and the changes over time. Comparisons were made pre and postimplementation of different surgical techniques over different time periods. The epochs relate to the learning curve, new equipment, and new techniques. Overall lead revision was observed at 5.7%, extension revision at 3.2%, infection rate at 1.2%, infarct without intracerebral hemorrhage at 0.8%, and intracerebral hemorrhage at 2.5% with a permanent deficit of 0.2%. An analysis and change in surgical technique which involved isolating the lead from the skin surface at both the cranial and retro-auricular incision also demonstrated a substantial decrease in lead fracture rate and infection rate. There was no mortality. This large series of patients and long-term follow-up demonstrates that risks are very low in comparison with other neurosurgical procedures, but DBS is still an elective procedure that necessitates extensive care and precision. In a rapidly evolving field, attention to surgical technique is imperative and will keep rates of complications at a minimum. © 2015 International Neuromodulation Society.

  11. Operation of a P300-based brain-computer interface by individuals with cervical spinal cord injury.

    Science.gov (United States)

    Ikegami, Shiro; Takano, Kouji; Saeki, Naokatsu; Kansaku, Kenji

    2011-05-01

    This study evaluates the efficacy of a P300-based brain-computer interface (BCI) with green/blue flicker matrices for individuals with cervical spinal cord injury (SCI). Ten individuals with cervical SCI (age 26-53, all male) and 10 age- and sex-matched able-bodied controls (age 27-52, all male) with no prior BCI experience were asked to input hiragana (Japanese alphabet) characters using the P300 BCI with two distinct types of visual stimuli, white/gray and green/blue, in an 8×10 flicker matrix. Both online and offline performance were evaluated. The mean online accuracy of the SCI subjects was 88.0% for the white/gray and 90.7% for the green/blue flicker matrices. The accuracy of the control subjects was 77.3% and 86.0% for the white/gray and green/blue, respectively. There was a significant difference in online accuracy between the two types of flicker matrix. SCI subjects performed with greater accuracy than controls, but the main effect was not significant. Individuals with cervical SCI successfully controlled the P300 BCI, and the green/blue flicker matrices were associated with significantly higher accuracy than the white/gray matrices. The P300 BCI with the green/blue flicker matrices is effective for use not only in able-bodied subjects, but also in individuals with cervical SCI. Copyright © 2010 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  12. A novel approach to nano topology via neutrosophic sets

    OpenAIRE

    M. Lellis Thivagar; Saeid Jafari; V. Sutha Devi; V. Antonysamy

    2018-01-01

    The main objective of this study is to introduce a new hybrid intelligent structure called Neutrosophic nano topology. Fuzzy nano topology and intuitionistic nano topology can also be deduced from the neutrosophic nano topology. Based on the neutrosophic nano approximations we have classified neutrosophic nano topology. Some properties like neutrosophic nano interior and neutrosophic nano closure are derived.

  13. Nano surface generation of grinding process using carbon nano tubes

    Indian Academy of Sciences (India)

    Nano surface finish has become an important parameter in the semiconductor, optical, electrical and mechanical industries. The materials used in these industries are classified as difficult to machine materials such as ceramics, glasses and silicon wafers. Machining of these materials up to nano accuracy is a great ...

  14. To be nano or not to be nano?

    Science.gov (United States)

    Joachim, Christian

    2005-02-01

    Nanomaterials, nanostructures, nanostructured materials, nanoimprint, nanobiotechnology, nanophysics, nanochemistry, radical nanotechnology, nanosciences, nanooptics, nanoelectronics, nanorobotics, nanosoldiers, nanomedecine, nanoeconomy, nanobusiness, nanolawyer, nanoethics to name a few of the nanos. We need a clear definition of all these burgeoning fields for the sake of the grant attribution, for the sake of research program definition, and to avoid everyone being lost in so many nanos.

  15. 1D Nano materials 2012

    International Nuclear Information System (INIS)

    Yanqiu Zhu, Y.; Ma, R.; Whitby, R.; Acquah, S.

    2013-01-01

    We witnessed an initial hyped period and enthusiasm on carbon nano tubes in the 1990s later went through a significant expansion into nano tubes of other materials (metal di chalcogenides, boron nitride, etc.) as well as various nano wires and nano rods. While much of the hype might have gone, the research on one-dimensional (1D) nano materials has matured as one of the most active research areas within the nano science and nano technology community, flourishing with ample, exciting, and new research opportunities. Just like any other research frontier, researchers working in the 1D nano materials field are constantly striving to develop new fundamental science as well as potential applications. It remains a common belief that versatility and tunability of 1D nano materials would challenge many new rising tasks coming from our resource and energy demanding modern society. The traditional semiconductor industry has produced so many devices and systems from transistors, sensors, lasers, and LEDs to more sophisticated solar panels, which are now part of our daily lives. By down sizing the core components or parts to 1D form, one might wonder how fundamentally the dimensionality and morphology would impact the device performance, this is, as always, requiring us to fully understand the structure-property relationship in 1D nano materials. It may be equally crucial in connecting discovery-driven fundamental science to market-driven technology industry concerning potentially relevant findings derived from these novel materials. The importance of a platform that allows active researchers in this field to present their new development in a timely and efficient manner is therefore self-evident. Following the success of two early special issues devoted to 1D nano materials, this is the third one in a row organized by the same group of guest editors, attesting that such a platform has been well received by the readers

  16. When math operations have visuospatial meanings versus purely symbolic definitions: Which solving stages and brain regions are affected?

    Science.gov (United States)

    Pyke, Aryn A; Fincham, Jon M; Anderson, John R

    2017-06-01

    How does processing differ during purely symbolic problem solving versus when mathematical operations can be mentally associated with meaningful (here, visuospatial) referents? Learners were trained on novel math operations (↓, ↑), that were defined strictly symbolically or in terms of a visuospatial interpretation (operands mapped to dimensions of shaded areas, answer = total area). During testing (scanner session), no visuospatial representations were displayed. However, we expected visuospatially-trained learners to form mental visuospatial representations for problems, and exhibit distinct activations. Since some solution intervals were long (~10s) and visuospatial representations might only be instantiated in some stages during solving, group differences were difficult to detect when treating the solving interval as a whole. However, an HSMM-MVPA process (Anderson and Fincham, 2014a) to parse fMRI data identified four distinct problem-solving stages in each group, dubbed: 1) encode; 2) plan; 3) compute; and 4) respond. We assessed stage-specific differences across groups. During encoding, several regions implicated in general semantic processing and/or mental imagery were more active in visuospatially-trained learners, including: bilateral supramarginal, precuneus, cuneus, parahippocampus, and left middle temporal regions. Four of these regions again emerged in the computation stage: precuneus, right supramarginal/angular, left supramarginal/inferior parietal, and left parahippocampal gyrus. Thus, mental visuospatial representations may not just inform initial problem interpretation (followed by symbolic computation), but may scaffold on-going computation. In the second stage, higher activations were found among symbolically-trained solvers in frontal regions (R. medial and inferior and L. superior) and the right angular and middle temporal gyrus. Activations in contrasting regions may shed light on solvers' degree of use of symbolic versus mental

  17. Application of Gaia Analysis Software AGIS to Nano-JASMINE

    Science.gov (United States)

    Yamada, Y.; Lammers, U.; Gouda, N.

    2011-07-01

    The core data reduction for the Nano-JASMINE mission is planned to be done with Gaia's Astrometric Global Iterative Solution (AGIS). Nano-JASMINE is an ultra small (35 kg) satellite for astrometry observations in Japan and Gaia is ESA's large (over 1000 kg) next-generation astrometry mission. The accuracy of Nano-JASMINE is about 3 mas, comparable to the Hipparcos mission, Gaia's predecessor some 20 years ago. It is challenging that such a small satellite can perform real scientific observations. The collaboration for sharing software started in 2007. In addition to similar design and operating principles of the two missions, this is possible thanks to the encapsulation of all Gaia-specific aspects of AGIS in a Parameter Database. Nano-JASMINE will be the test bench for the Gaia AGIS software. We present this idea in detail and the necessary practical steps to make AGIS work with Nano-JASMINE data. We also show the key mission parameters, goals, and status of the data reduction for the Nano-JASMINE.

  18. The many faces of nano in newspaper reporting

    International Nuclear Information System (INIS)

    Boholm, Max; Boholm, Åsa

    2012-01-01

    The morpheme nano in languages such as Swedish and English is a constituent of many words. This article linguistically analyses the meaning potential of nano by focusing on word use in a Swedish newspaper corpus comprising 2,564 articles (1.6 million words) covering a 22-year period (1988–2010). Close to 400 word forms having nano as a constituent have been identified and analyzed. The results suggest that nano covers a broad and heterogeneous conceptual field: (i) as a prefix of the SI system; (ii) in relation to the scientific activities of nanoscience and nanotechnology, including their sub-processes and actors; and (iii) in relation to objects. The identified meanings of nano, besides the standard definition (i.e. ‘billionth part’ in relation to SI units), are ‘operating at the nanometre level’ in relation to activities and their actors and ‘nanometre sized’ and ‘nanotechnological’ in relation to objects; in addition, the less precise and non-technical meaning ‘very small’ is identified. We discuss the implications of the findings for a hypothesis about media influence on public understanding of technology, suggesting that repeated findings in Europe and the USA of little self-reported understanding and knowledge of nanotechnology or nanoscience among the public make sense in light of the polysemy of nano reflected in its broad variety of verbal forms and usages.

  19. The many faces of nano in newspaper reporting

    Science.gov (United States)

    Boholm, Max; Boholm, Åsa

    2012-02-01

    The morpheme nano in languages such as Swedish and English is a constituent of many words. This article linguistically analyses the meaning potential of nano by focusing on word use in a Swedish newspaper corpus comprising 2,564 articles (1.6 million words) covering a 22-year period (1988-2010). Close to 400 word forms having nano as a constituent have been identified and analyzed. The results suggest that nano covers a broad and heterogeneous conceptual field: (i) as a prefix of the SI system; (ii) in relation to the scientific activities of nanoscience and nanotechnology, including their sub-processes and actors; and (iii) in relation to objects. The identified meanings of nano, besides the standard definition (i.e. `billionth part' in relation to SI units), are `operating at the nanometre level' in relation to activities and their actors and `nanometre sized' and `nanotechnological' in relation to objects; in addition, the less precise and non-technical meaning `very small' is identified. We discuss the implications of the findings for a hypothesis about media influence on public understanding of technology, suggesting that repeated findings in Europe and the USA of little self-reported understanding and knowledge of nanotechnology or nanoscience among the public make sense in light of the polysemy of nano reflected in its broad variety of verbal forms and usages.

  20. PREFACE: Nano- and microfluidics Nano- and microfluidics

    Science.gov (United States)

    Jacobs, Karin

    2011-05-01

    The field of nano- and microfluidics emerged at the end of the 1990s parallel to the demand for smaller and smaller containers and channels for chemical, biochemical and medical applications such as blood and DNS analysis [1], gene sequencing or proteomics [2, 3]. Since then, new journals and conferences have been launched and meanwhile, about two decades later, a variety of microfluidic applications are on the market. Briefly, 'the small flow becomes mainstream' [4]. Nevertheless, research in nano- and microfluidics is more than downsizing the spatial dimensions. For liquids on the nanoscale, surface and interface phenomena grow in importance and may even dominate the behavior in some systems. The studies collected in this special issue all concentrate on these type of systems and were part ot the priority programme SPP1164 'Nano- and Microfluidics' of the German Science Foundation (Deutsche Forschungsgemeinschaft, DFG). The priority programme was initiated in 2002 by Hendrik Kuhlmann and myself and was launched in 2004. Friction between a moving liquid and a solid wall may, for instance, play an important role so that the usual assumption of a no-slip boundary condition is no longer valid. Likewise, the dynamic deformations of soft objects like polymers, vesicles or capsules in flow arise from the subtle interplay between the (visco-)elasticity of the object and the viscous stresses in the surrounding fluid and, potentially, the presence of structures confining the flow like channels. Consequently, new theories were developed ( see articles in this issue by Münch and Wagner, Falk and Mecke, Bonthuis et al, Finken et al, Almenar and Rauscher, Straube) and experiments were set up to unambiguously demonstrate deviations from bulk, or 'macro', behavior (see articles in this issue by Wolff et al, Vinogradova and Belyaev, Hahn et al, Seemann et al, Grüner and Huber, Müller-Buschbaum et al, Gutsche et al, Braunmüller et al, Laube et al, Brücker, Nottebrock et al

  1. Neuroscience, brains, and computers

    Directory of Open Access Journals (Sweden)

    Giorno Maria Innocenti

    2013-07-01

    Full Text Available This paper addresses the role of the neurosciences in establishing what the brain is and how states of the brain relate to states of the mind. The brain is viewed as a computational deviceperforming operations on symbols. However, the brain is a special purpose computational devicedesigned by evolution and development for survival and reproduction, in close interaction with theenvironment. The hardware of the brain (its structure is very different from that of man-made computers.The computational style of the brain is also very different from traditional computers: the computationalalgorithms, instead of being sets of external instructions, are embedded in brain structure. Concerningthe relationships between brain and mind a number of questions lie ahead. One of them is why andhow, only the human brain grasped the notion of God, probably only at the evolutionary stage attainedby Homo sapiens.

  2. HELICoiD project: a new use of hyperspectral imaging for brain cancer detection in real-time during neurosurgical operations

    Science.gov (United States)

    Fabelo, Himar; Ortega, Samuel; Kabwama, Silvester; Callico, Gustavo M.; Bulters, Diederik; Szolna, Adam; Pineiro, Juan F.; Sarmiento, Roberto

    2016-05-01

    Hyperspectral images allow obtaining large amounts of information about the surface of the scene that is captured by the sensor. Using this information and a set of complex classification algorithms is possible to determine which material or substance is located in each pixel. The HELICoiD (HypErspectraL Imaging Cancer Detection) project is a European FET project that has the goal to develop a demonstrator capable to discriminate, with high precision, between normal and tumour tissues, operating in real-time, during neurosurgical operations. This demonstrator could help the neurosurgeons in the process of brain tumour resection, avoiding the excessive extraction of normal tissue and unintentionally leaving small remnants of tumour. Such precise delimitation of the tumour boundaries will improve the results of the surgery. The HELICoiD demonstrator is composed of two hyperspectral cameras obtained from Headwall. The first one in the spectral range from 400 to 1000 nm (visible and near infrared) and the second one in the spectral range from 900 to 1700 nm (near infrared). The demonstrator also includes an illumination system that covers the spectral range from 400 nm to 2200 nm. A data processing unit is in charge of managing all the parts of the demonstrator, and a high performance platform aims to accelerate the hyperspectral image classification process. Each one of these elements is installed in a customized structure specially designed for surgical environments. Preliminary results of the classification algorithms offer high accuracy (over 95%) in the discrimination between normal and tumour tissues.

  3. Micro/Nano manufacturing

    DEFF Research Database (Denmark)

    Tosello, Guido

    2017-01-01

    Micro- and nano-scale manufacturing has been the subject of an increasing amount of interest and research effort worldwide in both academia and industry over the past 10 years.Traditional (MEMS) manufacturing, but also precision manufacturing technologies have been developed to cover micro......-scale dimensions and accuracies. Furthermore, these fundamentally different technology ecosystems are currently combined in order to exploit strengths of both platforms. One example is the use of lithography-based technologies to establish nanostructures that are subsequently transferred to 3D geometries via...

  4. Nano Manufacturing - Products and Technologies

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Alting, Leo

    2004-01-01

    The use of micro and nano technologies in components and products not only sets new demands to the manufacturing technologies. Product concepts have to be rethought and redefined in order to implement the micro and nano technologies into functional systems. Both a technology driven and a product ...

  5. EDITORIAL: Nano Meets Spectroscopy Nano Meets Spectroscopy

    Science.gov (United States)

    Birch, David J. S.

    2012-08-01

    The multidisciplinary two-day Nano Meets Spectroscopy (NMS) event was held at the National Physical Laboratory (NPL), Teddington, UK, in September 2011. The event was planned from the outset to be at the interface of several areas—in particular, spectroscopy and nanoscience, and to bring together topics and people with different approaches to achieving common goals in biomolecular science. Hence the meeting cut across traditional boundaries and brought together researchers using diverse techniques, particularly fluorescence and Raman spectroscopy. Despite engaging common problems, these techniques are frequently seen as mutually exclusive with the two communities rarely interacting at conferences. The meeting was widely seen to have lived up to its billing in good measure. It attracted the maximum capacity of ~120 participants, including 22 distinguished speakers (9 from outside the UK), over 50 posters and a vibrant corporate exhibition comprising 10 leading instrument companies and IOP Publishing. The organizers were Professor David Birch (Chair), Dr Karen Faulds and Professor Duncan Graham of the University of Strathclyde, Professor Cait MacPhee of the University of Edinburgh and Dr Alex Knight of NPL. The event was sponsored by the European Science Foundation, the Institute of Physics, the Royal Society of Chemistry, NPL and the Scottish Universities Physics Alliance. The full programme and abstracts are available at http://sensor.phys.strath.ac.uk/nms/program.php. The programme was quite ambitious in terms of the breadth and depth of scope. The interdisciplinary and synergistic concept of 'X meets Y' played well, cross-fertilization between different fields often being a source of inspiration and progress. Fluorescence and Raman spectroscopy provided the core, but the meeting had little repetition and also attracted contributions on more specialist techniques such as CARS, super-resolution, single molecule and chiral methods. In terms of application the

  6. Nano-ceramics and its molding technologies

    International Nuclear Information System (INIS)

    Liu Jian; Xu Yunshu

    2007-01-01

    Nano-ceramics and its related knowledge were introduced. Fabrication of nano-ceramic powder, as well as the molding and sintering technologies of nano-ceramics were reviewed. Features of the present molding technologies were analyzed. The applications of nano-ceramics were prospected. (authors)

  7. Frontiers in nano-therapeutics

    CERN Document Server

    Tasnim, Nishat; Sai Krishna, Katla; Kalagara, Sudhakar; Narayan, Mahesh; Noveron, Juan C; Joddar, Binata

    2017-01-01

    This brief highlights recent research advances in the area of nano-therapeutics. Nanotechnology holds immense potential for application in a wide range of biological and engineering applications such as molecular sensors for disease diagnosis, therapeutic agents for the treatment of diseases, a vehicle for delivering therapeutics and imaging agents for theranostic applications, both in-vitro and in-vivo. The brief is grouped into the following sections namely, A) Discrete Nanosystems ; B) Anisotropic Nanoparticles; C) Nano-films/coated/layered and D) Nano-composites.

  8. An operational perspective of challenging statistical dogma while establishing a modern, secure distributed data management and imaging transport system: the Pediatric Brain Tumor Consortium phase I experience.

    Science.gov (United States)

    Onar, Arzu; Ramamurthy, Uma; Wallace, Dana; Boyett, James M

    2009-04-01

    The Pediatric Brain Tumor Consortium (PBTC) is a multidisciplinary cooperative research organization devoted to the study of correlative tumor biology and new therapies for primary central nervous system (CNS) tumors of childhood. The PBTC was created in 1999 to conduct early-phase studies in a rapid fashion in order to provide sound scientific foundation for the Children's Oncology Group to conduct definitive trials. The Operations and Biostatistics Center (OBC) of the PBTC is responsible for centrally administering study design and trial development, study conduct and monitoring, data collection and management as well as various regulatory and compliance processes. The phase I designs utilized for the consortium trials have accommodated challenges unique to pediatric trials such as body surface area (BSA)-based dosing in the absence of pediatric formulations of oral agents. Further during the past decade, the OBC has developed and implemented a state-of-the-art secure and efficient internet-based paperless distributed data management system. Additional web-based systems are also in place for tracking and distributing correlative study data as well as neuroimaging files. These systems enable effective communications among the members of the consortium and facilitate the conduct and timely reporting of multi-institutional early-phase clinical trials.

  9. Carbon nanotubes: from nano test tube to nano-reactor.

    Science.gov (United States)

    Khlobystov, Andrei N

    2011-12-27

    Confinement of molecules and atoms inside carbon nanotubes provides a powerful strategy for studying structures and chemical properties of individual molecules at the nanoscale. In this issue of ACS Nano, Allen et al. explore the nanotube as a template leading to the formation of unusual supramolecular and covalent structures. The potential of carbon nanotubes as reactors for synthesis on the nano- and macroscales is discussed in light of recent studies.

  10. Brain herniation

    Science.gov (United States)

    ... herniation; Uncal herniation; Subfalcine herniation; Tonsillar herniation; Herniation - brain ... Brain herniation occurs when something inside the skull produces pressure that moves brain tissues. This is most ...

  11. Nano Engineered Energetic Materials (NEEM)

    Science.gov (United States)

    2011-01-12

    Dryer, FL; Aksay, IA, Functionalized Graphene Sheet Colloids for Enhanced Fuel/Propellant Combustion, ACS NANO 3, 13, 3945-3954, 2009. 16. Weismiller...loading) which was not observed in other heterogeneous mixtures. Additional details on nano fuels (including graphene ) with liquid oxidizers can be...to the high reflectance of some samples black high temperature spray paint was used on ends of the samples to decrease ignition delay times and

  12. MICRO & NANO TECHNOLOGIES – APPLICATIONS, DESIGN AND INTEGRATION

    Directory of Open Access Journals (Sweden)

    Dorin LEŢ

    2010-05-01

    Full Text Available The science of micro-nano technologies represents a multidisciplinary research domain, which provokes active participation of specialist from multiple domains (physics, chemistry, biology, mathematics, electronics, medicine, a.o.. Nanotechnology is an applied science domain focusing the design, synthesis and characterization of materials and devices starting from individual atoms and molecules level up to supramolecular level of strains of molecules with 100 molecular diameters. Operations at this dimensions implies the understanding of new scientific principles and new materials properties, which take place at micro and nano scale and are used in the development of materials, devices and systems with new and improved functions and performances. The properties and basic functions of structures and material systems at nano scale may be changed based on the organization of the living mater on molecular “weak” interactions (hydrogen binds, electrostatic dipole, Van der Waals forces, surface forces, electrofluidic forces, a.o..

  13. Chemical Functionalization, Self-Assembly, and Applications of Nano materials and Nano composites 2014

    International Nuclear Information System (INIS)

    Yan, X.; Jiao, T.; Balan, L.; Chen, X.; Hu, M.Z.; Liu, W.

    2014-01-01

    The growing interests in nano materials and nano composites call for the development of processing techniques to obtain multiple functionalization nano structures and achieve the tailoring of specific features of the nanometer size. Functional nano materials and nano composites will expand the applied range of the original material and at the same time promote the development of inter discipline. Thus, the chemical functionalization and bottom-up assemblies of nano materials and subsequent applications will accelerate the development of nano science and nano technology.

  14. Comparison on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fibre lasers

    Science.gov (United States)

    Yang, Chun-Yu; Lin, Yung-Hsiang; Wu, Chung-Lun; Cheng, Chih-Hsien; Tsai, Din-Ping; Lin, Gong-Ru

    2018-06-01

    Comparisons on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fiber lasers (EDFLs) are performed. As opposed to the graphite nano-particles obtained by physically triturating the graphite foil, the tri-layer graphene nano-sheets is obtained by electrochemically exfoliating the graphite foil. To precisely control the size dispersion and the layer number of the exfoliated graphene nano-sheet, both the bias of electrochemical exfoliation and the speed of centrifugation are optimized. Under a threshold exfoliation bias of 3 volts and a centrifugation at 1000 rpm, graphene nano-sheets with an average diameter of 100  ±  40 nm can be obtained. The graphene nano-sheets with an area density of 15 #/µm2 are directly imprinted onto the end-face of a single-mode fiber made patchcord connector inside the EDFL cavity. Such electrochemically exfoliated graphene nano-sheets show comparable saturable absorption with standard single-graphene and perform the self-amplitude modulation better than physically triturated graphite nano-particles. The linear transmittance and modulation depth of the inserted graphene nano-sheets are 92.5% and 53%, respectively. Under the operation with a power gain of 21.5 dB, the EDFL can be passively mode-locked to deliver a pulsewidth of 454.5 fs with a spectral linewidth of 5.6 nm. The time-bandwidth product of 0.31 is close to the transform limit. The Kelly sideband frequency spacing of 1.34 THz is used to calculate the chirp coefficient as  ‑0.0015.

  15. Electrochemically synthesized Si nano wire arrays and thermoelectric nano structures

    International Nuclear Information System (INIS)

    Khuan, N.I.; Ying, K.K.; Nur Ubaidah Saidin; Foo, C.T.

    2012-01-01

    Thermoelectric nano structures hold great promise for capturing and directly converting into electricity some vast amount of low-grade waste heats now being lost to the environment (for example from nuclear power plant, fossil fuel burning, automotive and household appliances). In this study, large-area vertically-aligned silicon nano wire (SiNW) arrays were synthesized in an aqueous solution containing AgNO 3 and HF on p-type Si (100) substrate by self-selective electroless etching process. The etching conditions were systematically varied in order to achieve different stages of nano wire formation. Diameters of the SiNWs obtained varied from approximately 50 to 200 nm and their lengths ranged from several to a few tens of μm. Te/ Bi 2 Te 3 -Si thermoelectric core-shell nano structures were subsequently obtained via galvanic displacement of SiNWs in acidic HF electrolytes containing HTeO 2 + and Bi 3+ / HTeO 2 + ions. The reactions were basically a nano-electrochemical process due to the difference in redox potentials between the materials. the surface-modified SiNWs of core-shell structures had roughened surface morphologies and therefore, higher surface-t-bulk ratios compared to unmodified SiNWs. They have potential applications in sensors, photovoltaic and thermoelectric nano devices. Growth study on the SiNWs and core-shell nano structures produced is presented using various microscopy, diffraction and probe-based techniques for microstructural, morphological and chemical characterizations. (Author)

  16. Functional Nano fibers: Production and Applications

    International Nuclear Information System (INIS)

    Khatri, Z.; Kim, I.S.; Kim, S.H.

    2016-01-01

    Nano fibers are lighter material with higher surface area in comparison to polymeric film. The ease of producing functional nano fiber is another advantage over many nano materials. Functional nano fiber in particular has attained a greater interest in recent years. The applications of functional nano fibers are increasing in various technical fields such as water filter membranes, tissue engineering, biosensors, drug delivery systems, wound dressings, catalysis, antibacterial. This special issue is comprised of well-selective articles that discuss production of functional nano fibers their applications in different emerging fields. M. Zhang et al. have presented exciting work on drug delivery using nano fibers. They used collagen that was extracted from abandoned Rana chensinensis skin in northeastern China via an acid enzymatic extraction method. They demonstrated two different nano fiber-vancomycin (VCM) systems, that is, VCM blended nano fibers and core-shell nano fibers with VCM in the core, and both systems sustained control release for a period of 80 hours. Another work was presented by R. Takai et al. on blood purification using composite nano fibers. About 10% of the population worldwide is affected by chronic kidney disease (CKD). The authors developed nano fiber meshes zeolite-polymer composite nano fibers for efficient adsorption of creatinine, which is a simpler and more accessible method for hemodialysis (HD) patients.

  17. Radio elements / bottom salts separation by nano-filtration aided by complexation in a highly saline environment

    International Nuclear Information System (INIS)

    Gaubert, Eric

    1997-01-01

    This research thesis addresses the use of a membrane-based technique, nano-filtration, aided or not by complexation, for the processing of highly saline liquid effluents produced by radio-chemical decontamination. The objective is to separate non-radioactive elements (sodium nitrate) from radio-elements (caesium, strontium and actinides) in order to reduce the volume of wastes. Within the perspective of an industrial application, a system to concentrate the effluent is firstly defined. Different nano-filtration membranes are tested and reveal to be insufficient in highly saline environment. A stage of selective complexation of radio-elements is therefore considered before nano-filtration. The main factors affecting performance of nano-filtration-complexation (for a given membrane system) are identified: ionic force, pH, ligand content, trans-membrane pressure. Finally, a nano-filtration pilot is implemented to perform nano-filtration-complexation operations by remote handling on radioactive substances [fr

  18. The Potential Liver, Brain, and Embryo Toxicity of Titanium Dioxide Nanoparticles on Mice

    Science.gov (United States)

    Jia, Xiaochuan; Wang, Shuo; Zhou, Lei; Sun, Li

    2017-08-01

    Nanoscale titanium dioxide (nano-TiO2) has been widely used in industry and medicine. However, the safety of nano-TiO2 exposure remains unclear. In this study, we evaluated the liver, brain, and embryo toxicity and the underlying mechanism of nano-TiO2 using mice models. The results showed that titanium was distributed to and accumulated in the heart, brain, spleen, lung, and kidney of mice after intraperitoneal (i.p.) nano-TiO2 exposure, in a dose-dependent manner. The organ/body weight ratios of the heart, spleen, and kidney were significantly increased, and those of the brain and lung were decreased. High doses of nano-TiO2 significantly damaged the functions of liver and kidney and glucose and lipid metabolism, as showed in the blood biochemistry tests. Nano-TiO2 caused damages in mitochondria and apoptosis of hepatocytes, generation of reactive oxygen species, and expression disorders of protective genes in the liver of mice. We found ruptured and cracked nerve cells and inflammatory cell infiltration in the brain. We also found that the activities of constitutive nitric oxide synthases (cNOS), inducible NOS (iNOS), and acetylcholinesterase, and the levels of nitrous oxide and glutamic acid were changed in the brain after nano-TiO2 exposure. Ex vivo mouse embryo models exhibited developmental and genetic toxicity after high doses of nano-TiO2. The size of nano-TiO2 particles may affect toxicity, larger particles producing higher toxicity. In summary, nano-TiO2 exhibited toxicity in multiple organs in mice after exposure through i.p. injection and gavage. Our study may provide data for the assessment of the risk of nano-TiO2 exposure on human health.

  19. Metrology at the nano scale

    International Nuclear Information System (INIS)

    Sheridan, B.; Cumpson, P.; Bailey, M.

    2006-01-01

    Progress in nano technology relies on ever more accurate measurements of quantities such as distance, force and current industry has long depended on accurate measurement. In the 19th century, for example, the performance of steam engines was seriously limited by inaccurately made components, a situation that was transformed by Henry Maudsley's screw micrometer calliper. And early in the 20th century, the development of telegraphy relied on improved standards of electrical resistance. Before this, each country had its own standards and cross border communication was difficult. The same is true today of nano technology if it is to be fully exploited by industry. Principles of measurement that work well at the macroscopic level often become completely unworkable at the nano metre scale - about 100 nm and below. Imaging, for example, is not possible on this scale using optical microscopes, and it is virtually impossible to weigh a nano metre-scale object with any accuracy. In addition to needing more accurate measurements, nano technology also often requires a greater variety of measurements than conventional technology. For example, standard techniques used to make microchips generally need accurate length measurements, but the manufacture of electronics at the molecular scale requires magnetic, electrical, mechanical and chemical measurements as well. (U.K.)

  20. Nanos3 not nanos1 and nanos2 is a germ cell marker gene in large yellow croaker during embryogenesis.

    Science.gov (United States)

    Han, Kunhuang; Chen, Shihai; Cai, Mingyi; Jiang, Yonghua; Zhang, Ziping; Wang, Yilei

    2018-04-01

    In this study, three nanos gene subtypes (Lcnanos1, Lcnanos2 and Lcnanos3) from Larimichthys crocea, were cloned and characterized. We determined the spatio-temporal expression patterns of each subtype in tissues as well as the cellular localization of mRNA in embryos. Results showed that deduced Nanos proteins have two main homology domains: N-terminal CCR4/NOT1 deadenylase interaction domain and highly conserved carboxy-terminal region bearing two conserved CCHC zinc-finger motifs. The expression levels of Lcnanos1 in testis were significantly higher than other tissues, followed by heart, brain, eye, and ovary. Nevertheless, both Lcnanos2 and Lcnanos3 were restrictedly expressed in testis and ovary, respectively. No signals of Lcnanos1 and Lcnanos2 expression were detected at any developmental stages during embryogenesis. On the contrary, the signals of Lcnanos3 were detected in all stages examined. Lcnanos3 transcripts were firstly localized to the distal end of cleavage furrow at the 2-cell stage. Subsequently, mounting positive signals started to appear in a small number of cells as the embryo developed to blastula stage and early-gastrula stage. As development proceeded, positive signals were found in the primitive gonadal ridge. These cells of Lcnanos3 positive signals implied the specification of the future PGCs at this stage. It also suggested that PGCs of croaker originate from four clusters of cells which inherit maternal germ plasm at blastula stage. Furthermore, we preliminarily analyzed the migration route of PGCs in embryos of L. crocea. In short, this study laid the foundation for studies on specification and development of germ cell from L. crocea during embryogenesis. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Evidence that independent gut-to-brain and brain-to-gut pathways operate in the irritable bowel syndrome and functional dyspepsia: a 1-year population-based prospective study.

    Science.gov (United States)

    Koloski, N A; Jones, M; Talley, N J

    2016-09-01

    Traditionally, functional gastrointestinal disorders (FGIDs) are conceptualised as originating in the brain via stress pathways (brain-to-gut). It is uncertain how many with irritable bowel syndrome (IBS) and functional dyspepsia (FD) have a gut origin of symptoms (gut-to-brain pathway). To determine if there is a distinct brain-to-gut FGID (where psychological symptoms begin first) and separately a distinct gut-to-brain FGID (where gut symptoms start first). A prospective random population sample from Newcastle, Australia who responded to a validated survey in 2012 and completed a 1-year follow-up survey (n = 1900). The surveys contained questions on Rome III IBS and FD and the Hospital Anxiety and Depression Scale. We found that higher levels of anxiety and depression at baseline were significant predictors of developing IBS (OR = 1.31; 95% CI 1.06-1.61, P = 0.01; OR = 1.54; 95% CI 1.29-1.83, P intestinal features in many cases. © 2016 John Wiley & Sons Ltd.

  2. Nano structures for Medical Diagnostics Md

    International Nuclear Information System (INIS)

    Bellah, M.; Iqbal, S.M.; Bellah, M.; Iqbal, S.M.; Christensen, S.M.; Iqbal, S.M.; Iqbal, S.M.

    2012-01-01

    Nano technology is the art of manipulating materials on atomic or molecular scales especially to build nano scale structures and devices. The field is expanding quickly, and a lot of work is ongoing in the design, characterization, synthesis, and application of materials, structures, devices, and systems by controlling shape and size at nanometer scale. In the last few years, much work has been focused on the use of nano structures toward problems of biology and medicine. In this paper, we focus on the application of various nano structures and nano devices in clinical diagnostics and detection of important biological molecules. The discussion starts by introducing some basic techniques of micro-/nano scale fabrication that have enabled reproducible production of nano structures. The prospects, benefits, and limitations of using these novel techniques in the fields of bio detection and medical diagnostics are then discussed. Finally, the challenges of mass production and acceptance of nano technology by the medical community are considered.

  3. Green chemistry by nano-catalysis

    KAUST Repository

    Polshettiwar, Vivek; Varma, Rajender S.

    2010-01-01

    the homogeneous catalysts. This review focuses on the use of nano-catalysis for green chemistry development including the strategy of using microwave heating with nano-catalysis in benign aqueous reaction media which offers an extraordinary synergistic effect

  4. Dimensional micro and nano metrology

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; da Costa Carneiro, Kim; Haitjema, Han

    2006-01-01

    The need for dimensional micro and nano metrology is evident, and as critical dimensions are scaled down and geometrical complexity of objects is increased, the available technologies appear not sufficient. Major research and development efforts have to be undertaken in order to answer these chal......The need for dimensional micro and nano metrology is evident, and as critical dimensions are scaled down and geometrical complexity of objects is increased, the available technologies appear not sufficient. Major research and development efforts have to be undertaken in order to answer...... these challenges. The developments have to include new measuring principles and instrumentation, tolerancing rules and procedures as well as traceability and calibration. The current paper describes issues and challenges in dimensional micro and nano metrology by reviewing typical measurement tasks and available...

  5. Nano market and analysis of technology

    International Nuclear Information System (INIS)

    2001-10-01

    This book gives descriptions of summary of nano technology with meaning, character and field, trend of technical development in domestic, current condition of nano basic research in domestic, trend of technical development in foreign country such as summary, trend of technology by industrial field, machine and metronics, material and process, standard of nano mechanism, scale of market and trend, competitiveness of nano technology of major country and research development system in Japan, Korean company and major countries.

  6. Exergy analysis of the solar still integrated nano composite phase change materials

    International Nuclear Information System (INIS)

    Methre, V.K.; Eswaramoorthy, M.

    2015-01-01

    This paper communicates the exergy analysis of solar still integrated with nano composite phase change materials for design and operating parameters. Al_2O_3 nano materials (50 nm) is dispersed by weight ratio in paraffin wax at melting state and its thermophysical properties are evaluated using developed correlation. Exergy balance equation for basin liner, thermal energy storage, glass cover and saline water is developed and exergy efficiency is analysed. It is found that exergy efficiency is improved by higher weight ratio of Al_2O_3 nano materials with paraffin wax alone. (author)

  7. The Physiochemistry of Capped Nanosilver Predicts Its Biological Activity in Rat Brain Endothelial Cells (REBEC4)

    Science.gov (United States)

    The “capping” or coating of nanosilver (nanoAg) extends its potency by limiting its oxidation and aggregation and stabilizing its size and shape. The ability of such coated nanoAg to alter the permeability and activate oxidative stress pathways in rat brain endothelia...

  8. NanoSQUIDs: Basics & recent advances

    Science.gov (United States)

    José Martínez-Pérez, Maria; Koelle, Dieter

    2017-08-01

    Superconducting Quantum Interference Devices (SQUIDs) are one of the most popular devices in superconducting electronics. They combine the Josephson effect with the quantization of magnetic flux in superconductors. This gives rise to one of the most beautiful manifestations of macroscopic quantum coherence in the solid state. In addition, SQUIDs are extremely sensitive sensors allowing us to transduce magnetic flux into measurable electric signals. As a consequence, any physical observable that can be converted into magnetic flux, e.g., current, magnetization, magnetic field or position, becomes easily accessible to SQUID sensors. In the late 1980s it became clear that downsizing the dimensions of SQUIDs to the nanometric scale would encompass an enormous increase of their sensitivity to localized tiny magnetic signals. Indeed, nanoSQUIDs opened the way to the investigation of, e.g., individual magnetic nanoparticles or surface magnetic states with unprecedented sensitivities. The purpose of this chapter is to present a detailed survey of microscopic and nanoscopic SQUID sensors. We will start by discussing the principle of operation of SQUIDs, placing the emphasis on their application as ultrasensitive detectors for small localized magnetic signals. We will continue by reviewing a number of existing devices based on different kinds of Josephson junctions and materials, focusing on their advantages and drawbacks. The last sections are left for applications of nanoSQUIDs in the fields of scanning SQUID microscopy and magnetic particle characterization, placing special stress on the investigation of individual magnetic nanoparticles.

  9. Low Energy Dissipation Nano Device Research

    Science.gov (United States)

    Yu, Jenny

    2015-03-01

    The development of research on energy dissipation has been rapid in energy efficient area. Nano-material power FET is operated as an RF power amplifier, the transport is ballistic, noise is limited and power dissipation is minimized. The goal is Green-save energy by developing the Graphene and carbon nantube microwave and high performance devices. Higher performing RF amplifiers can have multiple impacts on broadly field, for example communication equipment, (such as mobile phone and RADAR); higher power density and lower power dissipation will improve spectral efficiency which translates into higher system level bandwidth and capacity for communications equipment. Thus, fundamental studies of power handling capabilities of new RF (nano)technologies can have broad, sweeping impact. Because it is critical to maximizing the power handling ability of grephene and carbon nanotube FET, the initial task focuses on measuring and understanding the mechanism of electrical breakdown. We aim specifically to determine how the breakdown voltage in graphene and nanotubes is related to the source-drain spacing, electrode material and thickness, and substrate, and thus develop reliable statistics on the breakdown mechanism and probability.

  10. The validation of the standard Chinese version of the European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire 30 (EORTC QLQ-C30 in pre-operative patients with brain tumor in China

    Directory of Open Access Journals (Sweden)

    Zhang Hong-ying

    2011-04-01

    Full Text Available Abstract Background Health related quality of life (HRQOL has increasingly emphasized on cancer patients. The psychometric properties of the standard Chinese version of the European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire 30 (EORTC QLQ-C30, version 3.0 in brain tumor patients wasn't proven, and there was no baseline HRQOL in brain tumor patients prior to surgery. Methods The questionnaire EORTC QLQ-C30 (version 3.0 was administered at three time points: T1, the first or the second day that patients were hospitalized after the brain tumor suspected or diagnosed by MRI or CT; T2, 1 to 2 days after T1, (T1 and T2 were both before surgery; T3, the day before discharge. Clinical variables included disease histologic types, cognitive function, and Karnofsky Performance Status. Results Cronbach's alpha coefficients for multi-item scales were greater than .70 and multitrait scaling analysis showed that most of the item-scale correlation coefficients met the standards of convergent and discriminant validity, except for the cognitive functioning scale. All scales and items exhibited construct validity. Score changes over peri-operation were observed in physical and role functioning scales. Compared with mixed cancer patients assessed after surgery but before adjuvant treatment, brain tumor patients assessed pre-surgery presented better function and fewer symptoms. Conclusions The standard Chinese version of the EORTC QLQ-C30 was overall a valid instrument to assess HRQOL in brain tumor patients in China. The baseline HRQOL in brain tumor patients pre-surgery was better than that in mixed cancer patients post-surgery. Future study should modify cognitive functioning scale and examine test-retest reliability and response validity.

  11. Fundamental Issues of Nano-fluid Behavior

    International Nuclear Information System (INIS)

    Williams, Wesley C.

    2006-01-01

    This paper will elucidate some of the behaviors of nano-fluids other than the abnormal conductivity enhancement, which are of importance to the experimental and engineering use of nano-fluids. Nano-fluid is the common name of any sol colloid involving nano-scale (less than 100 nm) sized particles dispersed within a base fluid. It has been shown previously that the dispersion of nano-particulate metallic oxides into water can increase thermal conductivity up to 30-40% over that of the base fluid and anomalously more than the mere weighed average of the colloid. There is a great potential for the use of nano-fluids as a way to enhance fluid/thermal energy transfer systems. Due to the recentness of nano-fluid science, there are still many issues which have not been fully investigated. This paper should act as a primer for the basic understanding of nano-fluid behavior. Particle size and colloid stability are of key importance to the functionality of nano-fluids. The pH and concentration/loading of nano-fluids can alter the size of the nano-particles and also the stability of the fluids. It will be shown through experiment and colloid theory the importance of these parameters. Furthermore, most of the existing literature uses volume percentage as the measure of particle loading, which can often be misleading. There will be discussion of this and other misleading ideas in nano-fluid science. (author)

  12. Single Molecule Nano-Metronome

    OpenAIRE

    Buranachai, Chittanon; McKinney, Sean A.; Ha, Taekjip

    2006-01-01

    We constructed a DNA-based nano-mechanical device called the nano-metronome. Our device is made by introducing complementary single stranded overhangs at the two arms of the DNA four-way junction. The ticking rates of this stochastic metronome depend on ion concentrations and can be changed by a set of DNA-based switches to deactivate/reactivate the sticky end. Since the device displays clearly distinguishable responses even with a single basepair difference, it may lead to a single molecule ...

  13. Single Molecule Nano-Metronome

    Science.gov (United States)

    Buranachai, Chittanon; McKinney, Sean A.; Ha, Taekjip

    2008-01-01

    We constructed a DNA-based nano-mechanical device called the nano-metronome. Our device is made by introducing complementary single stranded overhangs at the two arms of the DNA four-way junction. The ticking rates of this stochastic metronome depend on ion concentrations and can be changed by a set of DNA-based switches to deactivate/reactivate the sticky end. Since the device displays clearly distinguishable responses even with a single basepair difference, it may lead to a single molecule sensor of minute sequence differences of a target DNA. PMID:16522050

  14. Nano-pyramid arrays for nano-particle trapping

    NARCIS (Netherlands)

    Sun, Xingwu; Veltkamp, Henk-Willem; Berenschot, Johan W.; Gardeniers, Johannes G.E.; Tas, Niels Roelof

    2016-01-01

    Abstract In this paper we present the drastic miniaturization of nano-wire pyramids fabricated by corner lithography. A particle trapping device was fabricated in a well-defined and symmetrical array. The entrance and exit hole-size can be tuned by adjusting fabrication parameters. We describe here

  15. DLC nano-dot surfaces for tribological applications in MEMS devices

    International Nuclear Information System (INIS)

    Singh, R. Arvind; Na, Kyounghwan; Yi, Jin Woo; Lee, Kwang-Ryeol; Yoon, Eui-Sung

    2011-01-01

    With the invention of miniaturized devices like micro-electro-mechanical systems (MEMS), tribological studies at micro/nano-scale have gained importance. These studies are directed towards understanding the interactions between surfaces at micro/nano-scales, under relative motion. In MEMS devices, the critical forces, namely adhesion and friction restrict the smooth operation of the elements that are in relative motion. These miniaturized devices are traditionally made from silicon (Si), whose tribological properties are not good. In this paper, we present a short investigation of nano- and micro-tribological properties of diamond-like carbon (DLC) nano-dot surfaces. The investigation was undertaken to evaluate the potential of these surfaces for their possible application to the miniaturized devices. The tribological evaluation of the DLC nano-dot surfaces was done in comparison with bare Si (1 0 0) surfaces and DLC coated silicon surfaces. A commercial atomic force microscope (AFM) was used to measure adhesion and friction properties of the test materials at the nano-scale, whereas a custom-built micro-tribotester was used to measure their micro-friction property. Results showed that the DLC nano-dot surfaces exhibited superior tribological properties with the lowest values of adhesion force, and friction force both at the nano- and micro-scales, when compared to the bare Si (1 0 0) surfaces and DLC coated silicon surfaces. In addition, the DLC nano-dot surfaces showed no observable wear at the micro-scale, unlike the other two test materials. The superior tribological performance of the DLC nano-dot surfaces is attributed to their hydrophobic nature and the reduced area of contact projected by them.

  16. DLC nano-dot surfaces for tribological applications in MEMS devices

    Energy Technology Data Exchange (ETDEWEB)

    Singh, R. Arvind; Na, Kyounghwan [Nano-Bio Research Center, Korea Institute of Science and Technology, 39-1, Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Yi, Jin Woo; Lee, Kwang-Ryeol [Computational Science Center, Korea Institute of Science and Technology, 39-1, Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Yoon, Eui-Sung, E-mail: esyoon@kist.re.kr [Nano-Bio Research Center, Korea Institute of Science and Technology, 39-1, Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of)

    2011-02-01

    With the invention of miniaturized devices like micro-electro-mechanical systems (MEMS), tribological studies at micro/nano-scale have gained importance. These studies are directed towards understanding the interactions between surfaces at micro/nano-scales, under relative motion. In MEMS devices, the critical forces, namely adhesion and friction restrict the smooth operation of the elements that are in relative motion. These miniaturized devices are traditionally made from silicon (Si), whose tribological properties are not good. In this paper, we present a short investigation of nano- and micro-tribological properties of diamond-like carbon (DLC) nano-dot surfaces. The investigation was undertaken to evaluate the potential of these surfaces for their possible application to the miniaturized devices. The tribological evaluation of the DLC nano-dot surfaces was done in comparison with bare Si (1 0 0) surfaces and DLC coated silicon surfaces. A commercial atomic force microscope (AFM) was used to measure adhesion and friction properties of the test materials at the nano-scale, whereas a custom-built micro-tribotester was used to measure their micro-friction property. Results showed that the DLC nano-dot surfaces exhibited superior tribological properties with the lowest values of adhesion force, and friction force both at the nano- and micro-scales, when compared to the bare Si (1 0 0) surfaces and DLC coated silicon surfaces. In addition, the DLC nano-dot surfaces showed no observable wear at the micro-scale, unlike the other two test materials. The superior tribological performance of the DLC nano-dot surfaces is attributed to their hydrophobic nature and the reduced area of contact projected by them.

  17. Brain Tumors

    Science.gov (United States)

    A brain tumor is a growth of abnormal cells in the tissues of the brain. Brain tumors can be benign, with no cancer cells, ... cancer cells that grow quickly. Some are primary brain tumors, which start in the brain. Others are ...

  18. Aligned Layers of Silver Nano-Fibers

    Directory of Open Access Journals (Sweden)

    Andrii B. Golovin

    2012-02-01

    Full Text Available We describe a new dichroic polarizers made by ordering silver nano-fibers to aligned layers. The aligned layers consist of nano-fibers and self-assembled molecular aggregates of lyotropic liquid crystals. Unidirectional alignment of the layers is achieved by means of mechanical shearing. Aligned layers of silver nano-fibers are partially transparent to a linearly polarized electromagnetic radiation. The unidirectional alignment and density of the silver nano-fibers determine degree of polarization of transmitted light. The aligned layers of silver nano-fibers might be used in optics, microwave applications, and organic electronics.

  19. Traumatic Brain Injury Registry (TBI)

    Data.gov (United States)

    Department of Veterans Affairs — As the number of Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) Traumatic Brain Injury (TBI) patients has grown, so has the need to track and monitor...

  20. Nano materials for Cancer Phototheranostics

    International Nuclear Information System (INIS)

    Huang, P.; Ling, D.; Song, J; Liu, G.; Xie, J.

    2016-01-01

    The rapid development of advanced nano technology promises the integration of multiple diagnostic/therapeutic modalities into one nano platform for cancer theranostics. This issue compiles 3 review articles and 7 high-quality original research articles related to the field of nano material-based cancer theranostics. Photo therapies, such as photothermal therapy (PTT), photodynamic therapy (PDT), or photo-triggered drug/gene delivery, have gained considerable attention because of specific spatiotemporal selectivity and minimal invasiveness. Considering the inherent biocompatibility and biodegradability of proteins and peptides, P. Huang and coworkers summarized recent advances in the development of protein/peptide-based photothermal cancer theranostics, using protein/peptide as delivery vehicles or synthesis bio templates of PTT agents. M. G. O∼Toole and coworkers developed a near-infrared (NIR) responsive oligonucleotide-coated (AS1411, hairpin, or both) gold nanoplate loaded with doxorubicin (DOX), which is demonstrated to be nontoxic to cells without triggered release, while being acutely toxic to cells after 5 minutes of laser exposure to trigger DOX release. K. Na and coworkers described an acidic tumor pH-responsive nanophotomedicine (pH-NanoPM), which was prepared by self-assembly of a pH-responsive polymeric photo sensitizer (pH-PPS) consisting of pH-cleavable methoxypolyethylene glycol (pH-C-mPEG), for targeted PDT

  1. Increasing Possibilities of Nano suspension

    International Nuclear Information System (INIS)

    Sutradhar, K.B.; Khatun, S.; Luna, I.P.

    2013-01-01

    Nowadays, a very large proportion of new drug candidates emerging from drug discovery programmes are water insoluble and thus poorly bioavailable. To avoid this problem, nano technology for drug delivery has gained much interest as a way to improve the solubility problems. Nano refers to particles size range of 1-1000 nm. The reduction of drug particles into the submicron range leads to a significant increase in the dissolution rate and therefore enhances bioavailability. Nanosuspensions are part of nano technology. This interacts with the body at subcellular (i.e., molecular) scales with a high degree of specificity and can be potentially translated into targeted cellular and tissue-specific clinical applications designed to achieve maximal therapeutic efficacy with minimal side effects. Production of drugs as nanosuspensions can be developed for drug delivery systems as an oral formulation and no noral administration. Here, this review describes the methods of pharmaceutical nano suspension production including advantages and disadvantages, potential benefits, characterization tests, and pharmaceutical applications in drug delivery

  2. Brain surgery

    Science.gov (United States)

    Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... cut depends on where the problem in the brain is located. The surgeon creates a hole in ...

  3. Brain Malformations

    Science.gov (United States)

    Most brain malformations begin long before a baby is born. Something damages the developing nervous system or causes it ... medicines, infections, or radiation during pregnancy interferes with brain development. Parts of the brain may be missing, ...

  4. Nano-JASMINE Data Analysis and Publication

    Science.gov (United States)

    Yamada, Y.; Hara, T.; Yoshioka, S.; Kobayashi, Y.; Gouda, N.; Miyashita, H.; Hatsutori, Y.; Lammers, U.; Michalik, D.

    2012-09-01

    The core data reduction for the Nano-JASMINE mission is planned to be done with Gaia's Astrometric Global Iterative Solution (AGIS). A collaboration between the Gaia AGIS and Nano-JASMINE teams on the Nano-JASMINE data reduction started in 2007. The Nano-JASMINE team writes codes to generate AGIS input, and this is called Initial Data Treament (IDT). Identification of observed stars and their observed field of view, getting color index, are different from those of Gaia because Nano-JASMINE is ultra small satellite. For converting centroiding results on detector to the celestial sphere, orbit and attitude data of the satellite are used. In Nano-JASMINE, orbit information is derived from on board GPS data and attitude is processed from on-board star sensor data and on-ground Kalman filtering. We also show the Nano-JASMINE goals, status of the data publications and utilizations, and introduce the next Japanese space astrometric mission.

  5. Electrodeposition of nickel nano wire arrays

    International Nuclear Information System (INIS)

    Nur Ubaidah Saidin; Kok Kuan Ying; Ng Inn Khuan; Nurazila Mat Zali; Siti Salwa Zainal Abidin

    2010-01-01

    Synthesis, characterization and assembly of one-dimensional nickel nano wires prepared by template directed electrodeposition are discussed in this paper. Parallel arrays of high aspect ratio nickel nano wires were electrodeposited using electrolytes with different cations and pH. The nano wires were characterized using X-ray diffractometry and scanning electron microscopy. It was found that the orientations of the electro deposited Ni nano wires were governed by the deposition current and the electrolyte conditions. Free standing nickel nano wires can be obtained by dissolving the template. Due to the magnetic nature of the nano wires, magnetic alignment was employed to assemble and position the free standing nano wires in the device structure. (author)

  6. Pharmaceutical Applications of Polymeric Nano materials

    International Nuclear Information System (INIS)

    Wu, L.; Sun, L.

    2011-01-01

    With significant attention focused on nano science and nano technology in recent years, nano materials have been used in a wide variety of applications such as automotive, environmental, energy, catalysis, biomedical, drug delivery, and polymeric industries. Among those fields, the application of nano materials with pharmaceutical science is an emerging and rapidly growing field and has drawn increasing attention recently. Research and development in this field is mainly focused on several aspects such as the discoveries of novel functional nano materials, exploration on nanoparticles with controlled and targeted drug delivery characteristics, and investigation of bio functionalized and diagnostic nano materials. In this special issue, we have invited a few papers related to recent advances in pharmaceutical application of polymeric nano materials

  7. Self-organized semiconductor nano-network on graphene

    Science.gov (United States)

    Son, Dabin; Kim, Sang Jin; Lee, Seungmin; Bae, Sukang; Kim, Tae-Wook; Kang, Jae-Wook; Lee, Sang Hyun

    2017-04-01

    A network structure consisting of nanomaterials with a stable structural support and charge path on a large area is desirable for various electronic and optoelectronic devices. Generally, network structures have been fabricated via two main strategies: (1) assembly of pre-grown nanostructures onto a desired substrate and (2) direct growth of nanomaterials onto a desired substrate. In this study, we utilized the surface defects of graphene to form a nano-network of ZnO via atomic layer deposition (ALD). The surface of pure and structurally perfect graphene is chemically inert. However, various types of point and line defects, including vacancies/adatoms, grain boundaries, and ripples in graphene are generated by growth, chemical or physical treatments. The defective sites enhance the chemical reactivity with foreign atoms. ZnO nanoparticles formed by ALD were predominantly deposited at the line defects and agglomerated with increasing ALD cycles. Due to the formation of the ZnO nano-network, the photocurrent between two electrodes was clearly changed under UV irradiation as a result of the charge transport between ZnO and graphene. The line patterned ZnO/graphene (ZnO/G) nano-network devices exhibit sensitivities greater than ten times those of non-patterned structures. We also confirmed the superior operation of a fabricated flexible photodetector based on the line patterned ZnO/G nano-network.

  8. Near-field NanoThermoMechanical memory

    International Nuclear Information System (INIS)

    Elzouka, Mahmoud; Ndao, Sidy

    2014-01-01

    In this letter, we introduce the concept of NanoThermoMechanical Memory. Unlike electronic memory, a NanoThermoMechanical memory device uses heat instead of electricity to record, store, and recover data. Memory function is achieved through the coupling of near-field thermal radiation and thermal expansion resulting in negative differential thermal resistance and thermal latching. Here, we demonstrate theoretically via numerical modeling the concept of near-field thermal radiation enabled negative differential thermal resistance that achieves bistable states. Design and implementation of a practical silicon based NanoThermoMechanical memory device are proposed along with a study of its dynamic response under write/read cycles. With more than 50% of the world's energy losses being in the form of heat along with the ever increasing need to develop computer technologies which can operate in harsh environments (e.g., very high temperatures), NanoThermoMechanical memory and logic devices may hold the answer

  9. Synthetic Nano-Low Density Lipoprotein as Targeted Drug DeliveryVehicle for Glioblastoma Multiforme

    Energy Technology Data Exchange (ETDEWEB)

    Nikanjam, Mina; Blakely, Eleanor A.; Bjornstad, Kathleen A.; Shu,Xiao; Budinger, Thomas F.; Forte, Trudy M.

    2006-06-14

    This paper discribes a synthetic low density lipoprotein(LDL) made by complexing a 29 amino acid that consists of a lipid bindingdomain and the LDL receptor binding domain with a lipid microemulsion.The nano-LDL particles were intermdiate in size between LDL and HDL andbound to LDL receptors on GBM brain tumor cells. Synthetic nano-LDLuptake by GBM cells was LDL receptor specific and dependent on cellreceptor number. It is suggested that these synthetic particles can serveas a delivery vehicle for hydophobic anti-tumor drugs by targeting theLDL receptor.

  10. A novel fabrication method of silicon nano-needles using MEMS TMAH etching techniques

    International Nuclear Information System (INIS)

    Yan Sheping; Xu Yang; Yang Junyi; Wang Huiquan; Jin Zhonghe; Wang Yuelin

    2011-01-01

    Nano-needles play important roles in nanoscale operations. However, current nano-needle fabrication is usually expensive and controling the sizes and angles is complicated. We have developed a simple and low cost silicon nano-needle fabrication method using traditional microelectromechanical system (MEMS) tetramethyl ammonium hydroxide (TMAH) etching techniques. We take advantage of the fact that the decrease of the silicon etch rate in TMAH solutions exhibits an inverse fourth power dependence on the boron doping concentration in our nano-needle fabrication. Silicon nano-needles, with high aspect ratio and sharp angles θ as small as 2.9 deg., are obtained, which could be used for bio-sensors and nano-handling procedures, such as penetrating living cells. An analytic model is proposed to explain the etching evolution of the experimental results, which is used to predict the needle angle, length, and etching time. Based on our method, nano-needles with small acute angle θ can be obtained.

  11. From Gold Nano-particles through Nano-wire to Gold Nano-layers on Substrate

    Czech Academy of Sciences Publication Activity Database

    Švorčík, V.; Kolská, Z.; Slepička, P.; Siegel, J.; Hnatowicz, Vladimír

    2010-01-01

    Roč. 2010, G (2010), s. 1-57. ISBN 978-1-61668-009-1 Institutional support: RVO:61389005 Keywords : thin films * Au nano layers * AFM Subject RIV: BM - Solid Matter Physics ; Magnetism https://www.novapublishers.com/catalog/product_info.php?products_id=12909

  12. Antibacterial performance of nano polypropylene filter media containing nano-TiO{sub 2} and clay particles

    Energy Technology Data Exchange (ETDEWEB)

    Shafiee, Sara; Zarrebini, Mohammad; Naghashzargar, Elham, E-mail: e.naghashzargar@tx.iut.ac.ir; Semnani, Dariush, E-mail: d-semnani@cc.iut.ac.ir [Isfahan University of Technology, Department of Textile Engineering (Iran, Islamic Republic of)

    2015-10-15

    Disinfection and elimination of pathogenic microorganisms from liquid can be achieved by filtration process using antibacterial filter media. The advent of nanotechnology has facilitated the introduction of membranes consisting of nano-fiber in filtration operations. The melt electro-spun fibers due to their extremely small diameters are used in the production of this particular filtration medium. In this work, antibacterial polypropylene filter medium containing clay particles and nano-TiO{sub 2} were made using melt electro-spun technology. Antibacterial performance of polypropylene nano-filters was evaluated using E. coli bacteria. Additionally, filtration efficiency of the samples in terms fiber diameter, filter porosity, and fiber distribution using image processing technique was determined. Air permeability and dust aerosol tests were conducted to establish the suitability of the samples as a filter medium. It was concluded that as far as antibacterial property is concerned, nano-fibers filter media containing clay particles are preferential to similar media containing TiO{sub 2} nanoparticles.

  13. Growth of VO2 Nano wires from Supercooled Liquid Nano droplets and E-beam Irradiation for Ultra-sensitive sensor

    International Nuclear Information System (INIS)

    Byun, Ji Won; Baik, Jeong Min; Lee, Sang Hyun; Lee, Byung Cheol

    2011-01-01

    Vanadium dioxide is an interesting material on account of its easily accessible and sharp Mott metal-insulator transition at ∼ 68 .deg. C in the bulk, which is of great interest in sensing and catalytic applications. In this Paper, we describe the synthesis and properties of VO 2 nano wires as novel catalytic and gas sensor materials based on electron beam irradiation. High yields of single crystalline VO 2 nano wires are synthesized by atmospheric-pressure, physical vapor deposition using V 2 O 5 layer. Pd-decorated VO 2 nano wire sensors show extraordinary sensitivity towards hydrogen, an almost 3 order-of-magnitude increase in the current through the nano wire. By the Eb irradiation, the conductance of the nano wires significantly increased up to 5 times, reducing the response time by half and the operating temperature. The metal nanoparticles-VO 2 nano wire system will be very promising for high-sensitivity and high-selectivity under low temperature less than 100. deg. C

  14. Thermal Conductivity of Nano-fluids in Nano-channels

    OpenAIRE

    Frank, M; Asproulis, N; Drikakis, D; 4th Micro and Nano Flows Conference (MNF2014)

    2014-01-01

    This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, U...

  15. Nano catalysis: Academic Discipline and Industrial Realities

    International Nuclear Information System (INIS)

    Olveira, S.; Forster, S.P.; Seeger, S.

    2014-01-01

    Nano technology plays a central role in both academic research and industrial applications. Nano enabled products are not only found in consumer markets, but also importantly in business to business markets (B2B). One of the oldest application areas of nano technology is nano catalysis—an excellent example for such a B2 B market. Several existing reviews illustrate the scientific developments in the field of nano catalysis. The goal of the present review is to provide an up-to-date picture of academic research and to extend this picture by an industrial and economic perspective. We therefore conducted an extensive search on several scientific databases and we further analyzed more than 1,500 nano catalysis-related patents and numerous market studies. We found that scientists today are able to prepare nano catalysts with superior characteristics regarding activity, selectivity, durability, and recoverability, which will contribute to solve current environmental, social, and industrial problems. In industry, the potential of nano catalysis is recognized, clearly reflected by the increasing number of nano catalysis-related patents and products on the market. The current nano catalysis research in academic and industrial laboratories will therefore enable a wealth of future applications in the industry

  16. Editorial Nano structures for Medicine and Pharmaceuticals

    International Nuclear Information System (INIS)

    Xing-Jie, L.; Kumar, A.; Donglu, S.; Daxiang, C.

    2012-01-01

    The rapid developments in nano structured materials and nano technology will have profound impact in many areas of biomedical applications including delivery of drugs and biomolecules, tissue engineering, detection of bio markers, cancer diagnosis, cancer therapy, and imaging. This field is expanding quickly, and a lot of work is ongoing in the design, characterization, synthesis, and application of materials, for controlling shape and size at nanometer scale to develop highly advanced materials for biomedical application and even to design better pharmaceutical products. In recent years, novel nano structure with multi functionalities has been focused on the use of nano structures toward solving problems of biology and medicine. The main scope of this special issue is to demonstrate the latest achievement of nano technology and its application in nano medicine particularly in new approaches for drug delivery such as targeted drug delivery system, nano structure for drug storage, nano materials for tissue engineering, medical diagnosis and treatment, and generation of new kinds of materials from biological sources. Therefore, many critical issues in nano structured materials, particularly their applications in biomedicine, must be addressed before clinical applications. This special issue devotes several review and research articles encompassing various aspects of nano materials for medicine and pharmaceuticals.

  17. Theoretical Limits on Multiuser Molecular Communication in Internet of Nano-Bio Things.

    Science.gov (United States)

    Dinc, Ergin; Akan, Ozgur B

    2017-06-01

    In nano-bio networks, multiple transmitter-receiver pairs will operate in the same medium. Both inter-symbol interference and multi-user interference can cause saturation at the receiver side, and this effect may cause an outage. Thus, we propose a tractable framework to calculate the theoretical operating points for fully absorbing receiver.

  18. Nano-JASMINE: use of AGIS for the next astrometric satellite

    Science.gov (United States)

    Yamada, Y.; Gouda, N.; Lammers, U.

    The core data reduction for the Nano-JASMINE mission is planned to be done with Gaia's Astrometric Global Iterative Solution (AGIS). The collaboration started at 2007 prompted by Uwe Lammers' proposal. In addition to similar design and operating principles of the two missions, this is possible thanks to the encapsulation of all Gaia-specific aspects of AGIS in a Parameter Database. Nano-JASMINE will be the test bench for Gaia AGIS software. We present this idea in detail and the necessary practical steps to make AGIS work with Nano-JASMINE data. We also show the key mission parameters, goals, and status of the data reduction for the Nano-JASMINE.

  19. Gas selectivity of SILAR grown CdS nano-bulk junction

    Science.gov (United States)

    Jayakrishnan, R.; Nair, Varun G.; Anand, Akhil M.; Venugopal, Meera

    2018-03-01

    Nano-particles of cadmium sulphide were deposited on cleaned copper substrate by an automated sequential ionic layer adsorption reaction (SILAR) system. The grown nano-bulk junction exhibits Schottky diode behavior. The response of the nano-bulk junction was investigated under oxygen and hydrogen atmospheric conditions. The gas response ratio was found to be 198% for Oxygen and 34% for Hydrogen at room temperature. An increase in the operating temperature of the nano-bulk junction resulted in a decrease in their gas response ratio. A logarithmic dependence on the oxygen partial pressure to the junction response was observed, indicating a Temkin isothermal behavior. Work function measurements using a Kelvin probe demonstrate that the exposure to an oxygen atmosphere fails to effectively separate the charges due to the built-in electric field at the interface. Based on the benefits like simple structure, ease of fabrication and response ratio the studied device is a promising candidate for gas detection applications.

  20. Intraoperative appearance of the resection area in brain-tumor operations in an open 0,5 MRT; Intraoperatives Erscheinungsbild des Resektionsbereichs bei Hirntumoroperationen in einem offenen 0,5-T-MRT

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, J. [Universitaetsklinik fuer Diagnostische Radiologie, Leipzig (Germany). Arbeitsbereich Neuroradiologie; Schneider, J.P.; Schulz, T. [Universitaetsklinik fuer Diagnostische Radiologie, Leipzig (Germany); Seifert, V.; Trantakis, C. [Universitaetsklinik fuer Neurochirurgie, Leipzig (Germany); Kellermann, S. [Leipzig Univ. (Germany). Abt. fuer Neuropathologie

    1998-11-01

    During MRI-controlled resection of brain tumors using an open MRI system, operation-induced alterations may occur, especially enhancement of the resection cavity wall. This may simulate tumor areas, resulting in false assessment of the resection or resection of non-tumorous areas. Based on 42 MRI- and biopsy-controlled brain tumor resections in an 0.5 T open MRI (Signa SP, GE), the appearance and origin of operation-induced reactions are analyzed. In our opinion, there is a superposition of preformed peritumoral reactions by operation-induced microcontusions. The beginning of the cavity wall enhancement needs at least 10-15 min. MRI-controlled analysis of the intraoperative steps by the neurosurgeon and neuroradiologist allows discrimination of operation-induced reactions from tumor areas and leads to safe operation. (orig.) [Deutsch] Bei der intraoperativen Kontrolle von Hirntumorresektionen in offenen MRT-Geraeten kann es zu operativ induzierten Veraenderungen, insbesondere Rand-enhancement-Zonen, kommen. Diese koennen Tumorreste vortaeuschen, so dass die Radikalitaet des Eingriffs unterschaetzt wird oder nicht tumortragende Hirnareale entfernt werden. Ergebnisse und Diskussion: Anhand von 42 in einem offenen 0,5-T-MRT (Signa SP, GE) vorgenommenen, biopsiekontrollierten Hirntumoroperationen werden Erscheinungsbild und Entstehungsweise der Randveraenderungen analysiert. Bei den haeufig vorzufindenden Rand-enhancement-Zonen handelt es sich um eine Ueberlagerung von praeformierten Tumorrandreaktionen mit Mikrokontusionen. Die Ausbildung dieser Veraenderungen braucht eine Mindestzeit von 10-15 min. Die staendige Analyse der die Tumorresektion begleitenden MRT-Kontrollen durch den Operateur und einen mit der Problematik vertrauten Radiologen gestattet in der Regel die Differenzierung der operativ induzierten Veraenderungen und erhoeht damit die Sicherheit des Eingriffs. (orig.)

  1. HIT'91 (prospective, co-operative study for the treatment of malignant brain tumors in childhood): accuracy and acute toxicity of the irradiation of the craniospinal axis

    International Nuclear Information System (INIS)

    Kortmann, R.D.; Timmermann, B.; Bamberg, M.; Kuehl, J.; Willich, N.; Flentje, M.; Meisner, C.

    1999-01-01

    Background: It was the aim of the quality control program of the randomized trial HIT '91 (intensive chemotherapy before irradiation versus maintenance chemotherapy after irradiation) to assess prospectively the quality of neuroaxis irradiation with respect to the protocol guidelines and to evaluate acute toxicity with respect to treatment arm. Patients, Materials and Methods: Data of 134 patients undergoing irradiation of the craniospinal axis were available. Positioning aids, shielding techniques, treatment machines, choice of energy, total dose and fractionation were evaluated. A total of 651 simulation and verification films were analyzed to assess the coverage of the clinical target volume (whole brain, posterior fossa, sacral nerve roots) and deviations of field alignment between simulation and verification of first treatment. Field matching between whole brain and adjacent cranial spinal fields was analyzed with respect to site and width of junction. Acute maximal side effects were evaluated according to a modified WHO score for neurotoxicity, infections, skin, mucosa and myelotoxicity. Results: In 91.3% of patients contemporary positioning aids and individualized shielding techniques were used to assure a reproducible treatment. In 98 patients (73.1%) linear accelerators and in 36 patients (26.8%) 60 Cobalt machines were used. Single and total dose were administered according to the protocol guidelines in more than 90% of patients. In 20.2% of patients the cribriform plate, in 1.4% the middle cranial fossa and in 21.1% the posterior fossa and in 4.5% the 2nd sacral segment were incompletely encompassed by the treatment portals. Ninety-five percent of deviations of field alignment were less than 13.0 mm (whole brain) and 12 mm (cranial spinal field) with a random error between 4.9 and 7.6 mm (whole brain) and 6.9 mm and 9.9 mm (spinal canal), respectively. In 77.5% of patients the junctions between whole brain and cranial spinal fields were placed without a

  2. Radiation brain dose to vascular surgeons during fluoroscopically guided interventions is not effectively reduced by wearing lead equivalent surgical caps.

    Science.gov (United States)

    Kirkwood, Melissa L; Arbique, Gary M; Guild, Jeffrey B; Zeng, Katie; Xi, Yin; Rectenwald, John; Anderson, Jon A; Timaran, Carlos

    2018-03-12

    Radiation to the interventionalist's brain during fluoroscopically guided interventions (FGIs) may increase the incidence of cerebral neoplasms. Lead equivalent surgical caps claim to reduce radiation brain doses by 50% to 95%. We sought to determine the efficacy of the RADPAD (Worldwide Innovations & Technologies, Lenexa, Kan) No Brainer surgical cap (0.06 mm lead equivalent at 90 kVp) in reducing radiation dose to the surgeon's and trainee's head during FGIs and to a phantom to determine relative brain dose reductions. Optically stimulated, luminescent nanoDot detectors (Landauer, Glenwood, Ill) inside and outside of the cap at the left temporal position were used to measure cap attenuation during FGIs. To check relative brain doses, nanoDot detectors were placed in 15 positions within an anthropomorphic head phantom (ATOM model 701; CIRS, Norfolk, Va). The phantom was positioned to represent a primary operator performing femoral access. Fluorography was performed on a plastic scatter phantom at 80 kVp for an exposure of 5 Gy reference air kerma with or without the hat. For each brain location, the percentage dose reduction with the hat was calculated. Means and standard errors were calculated using a pooled linear mixed model with repeated measurements. Anatomically similar locations were combined into five groups: upper brain, upper skull, midbrain, eyes, and left temporal position. This was a prospective, single-center study that included 29 endovascular aortic aneurysm procedures. The average procedure reference air kerma was 2.6 Gy. The hat attenuation at the temporal position for the attending physician and fellow was 60% ± 20% and 33% ± 36%, respectively. The equivalent phantom measurements demonstrated an attenuation of 71% ± 2.0% (P < .0001). In the interior phantom locations, attenuation was statistically significant for the skull (6% ± 1.4%) and upper brain (7.2% ± 1.0%; P < .0001) but not for the middle brain (1.4% ± 1.0%; P = .15

  3. NanoChemistry Group at DTU uses NanoSight's NTA System for Nanoparticle Characterization

    DEFF Research Database (Denmark)

    2011-01-01

    (Nanowerk News) NanoSight, leading manufacturers of unique nanoparticle characterization technology, describes how the Nano Chemistry group at DTU Copenhagen is utilizing nanoparticle tracking analysis, NTA, in its research and teaching programs....

  4. Nano- and micro-electromechanical systems fundamentals of nano- and microengineering

    CERN Document Server

    Lyshevski, Sergey Edward

    2005-01-01

    NANOTECHNOLOGY AND MICROTECHNOLOGY (NANO- AND MICRO- SCIENCE, ENGINEERING AND TECHNOLOGY), AND BEYOND Introduction and Overview: From Micro- to Nano- and Beyond to Stringo-Scale Introductory Definitions to the Subjects Current Developments and Needs for Coherent Revolutionary Developments Societal Challenges and Implications NANO- AND MICROSCALE SYSTEMS, DEVICES, AND STRUCTURES Sizing Features: From Micro- to Nano-, and from Nano- to Stringo-Scale MEMS and NEMS Definitions Introduction to Taxonomy of Nano- and Microsystem Synthesis and Design Introduction to Design and Optimization of Nano- and Microsystems in the Behavioral Domain NANO- AND MICROSYSTEMS: CLASSIFICATION AND CONSIDERATION Biomimetics, Biological Analogies,and Design of NEMS and MEMS Micro- and Nanoelectromechanical Systems: Scaling Laws and Mathematical Modeling MEMS Examples and MEMS Architectures Introduction to Microfabrication and Micromachining FUNDAMENTALS OF MICROFABRICATION AND MEMS FABRICATION TECHNOLOGIES Introducti...

  5. Mothership - Affordable Exploration of Planetary Bodies through Individual Nano-Sats and Swarms

    Science.gov (United States)

    DiCorcia, James D.; Ernst, Sebastian M.; Grace, J. Mike; Gump, David P.; Lewis, John S.; Foulds, Craig F.; Faber, Daniel R.

    2015-04-01

    One concept to enable broad participation in the scientific exploration of small bodies is the Mothership mission architecture which delivers third-party nano-sats, experiments, and sensors to a near Earth asteroid or comet. Deep Space Industries' Mothership service includes delivery of nano-sats, communication to Earth, and visuals of the asteroid surface and surrounding area. It allows researchers to house their instruments in a low-cost nano-sat platform that does not require the high-performance propulsion or deep space communication capabilities that otherwise would be required for a solo asteroid mission. This enables organizations with relatively low operating budgets to closely examine an asteroid with highly specialized sensors of their own choosing, while the nano-sats can be built or commissioned by a variety of smaller institutions, companies, or agencies. In addition, the Mothership and its deployed nano-sats can offer a platform for instruments which need to be distributed over multiple spacecraft. The Mothership is designed to carry 10 to 12 nano-sats, based upon a variation of the Cubesat standard, with some flexibility on the specific geometry. The Deep Space Nano-Sat reference design is a 14.5 cm cube, which accomodates the same volume as a traditional 3U Cubesat. This design was found to be more favorable for deep space due to its thermal characteristics. The CubeSat standard was originally designed with operations in low Earth orbit in mind. By deliberately breaking the standard, Deep Space Nano-Sats offer better performance with less chance of a critical malfunction in the more hostile deep space environment. The first mission can launch as early as Q4 2017, with subsequent, regular launches through the 2020's.

  6. Survey on Recent Designs of Compliant Micro-/Nano-Positioning Stages

    Directory of Open Access Journals (Sweden)

    Zeyi Wu

    2018-02-01

    Full Text Available Micromanipulation is a hot topic due to its enabling role in various research fields. In order to perform a high precision operation at a small scale, compliant mechanisms have been proposed and applied for decades. In microscale manipulation, micro-/nano-positioning is the most fundamental operation because a precision positioning is the premise of subsequent operations. This paper is concentrated on reviewing the state-of-the-art research on complaint micro-/nano-positioning stage design in recent years. It involves the major processes and components for designing a compliant positioning stage, e.g., actuator selection, stroke amplifier design, connecting scheme of the multi-DOF stage and structure optimization. The review provides a reference to design a compliant micro-/nano-positioning stage for pertinent applications.

  7. Computational Intelligence in a Human Brain Model

    Directory of Open Access Journals (Sweden)

    Viorel Gaftea

    2016-06-01

    Full Text Available This paper focuses on the current trends in brain research domain and the current stage of development of research for software and hardware solutions, communication capabilities between: human beings and machines, new technologies, nano-science and Internet of Things (IoT devices. The proposed model for Human Brain assumes main similitude between human intelligence and the chess game thinking process. Tactical & strategic reasoning and the need to follow the rules of the chess game, all are very similar with the activities of the human brain. The main objective for a living being and the chess game player are the same: securing a position, surviving and eliminating the adversaries. The brain resolves these goals, and more, the being movement, actions and speech are sustained by the vital five senses and equilibrium. The chess game strategy helps us understand the human brain better and easier replicate in the proposed ‘Software and Hardware’ SAH Model.

  8. Conductive oxide cantilever for cryogenic nano-potentiometry

    International Nuclear Information System (INIS)

    Hiroya, Tsutomu; Inagaki, Katsuhiko; Tanda, Satoshi; Tsuneta, Taku; Yamaya, Kazuhiko

    2003-01-01

    Nanoscale electrical transport properties have attracted attentions because of new phenomena such as ballistic transport, quantized resistance, and Coulomb blockade. For measurement of nanoscale resistance, we have been developing a cryogenic atomic force microscope that can operate at 1.8 K. To use it as an electrode, we coated the cantilever with conductive oxides of TiO and indium tin oxide (ITO). We verified that TiO and ITO thin films remain conductive even at 4.2 K. Also we measured I-V characteristics of the tip-sample contact with a standard sample of NbSe 2 single crystal, and found that the conductive coats were not lost under large stresses due to the tip-sample contact. Moreover, we succeeded in obtaining a room temperature nano-potentiometry of a gold thin film with the ITO coated cantilever. In conclusion, the TiO and ITO coated cantilevers are applicable to cryogenic nano-potentiometry

  9. Mode competition and hopping in optomechanical nano-oscillators

    Science.gov (United States)

    Zhang, Xingwang; Lin, Tong; Tian, Feng; Du, Han; Zou, Yongchao; Chau, Fook Siong; Zhou, Guangya

    2018-04-01

    We investigate the inter-mode nonlinear interaction in the multi-mode optomechanical nano-oscillator which consists of coupled silicon nanocantilevers, where the integrated photonic crystal nanocavities provide the coupling between the optical and mechanical modes. Due to the self-saturation and cross-saturation of the mechanical gain, the inter-mode competition is observed, which leads to the bistable operation of the optomechanical nano-oscillator: only one of the mechanical modes can oscillate at any one time, and the oscillation of one mode extremely suppresses that of the other with a side mode suppression ratio (SMSR) up to 40 dB. In the meantime, mode hopping, i.e., the optomechanical oscillation switches from one mode to the other, is also observed and found to be able to be provoked by excitation laser fluctuations.

  10. Nano materials for Medical and Dental Applications

    International Nuclear Information System (INIS)

    Yub Kwon, T.; Oh, D.S.; Narayanan, R.

    2015-01-01

    Welcome to this special issue. Nano science and nano technology concepts are applicable across all fields of science and a more widespread application of nano materials and nano technologies is imminent or already occurring in many areas, including health care. Today is scientists take those cutting-edge technologies and concepts and apply them to medicine and dentistry. They are finding a wide variety of ways to make medical and dental materials at the nano scale to take advantage of their enhanced physical and biological properties.The purpose of this special issue is to publish high-quality research papers as well as review articles addressing recent advances in the field of nano materials for medical and dental applications. A particular interest is given to papers exploring or discussing nano materials and nano technologies related to delivery system, bonding substitutes, and surface modification techniques applicable in these areas. For this special issue, several investigators were invited to contribute original research findings that can stimulate continuing efforts to understand the cutting-edge applications of nano materials in medicine and dentistry.

  11. Bio/Nano Electronic Devices and Sensors

    National Research Council Canada - National Science Library

    Jones, W. K

    2008-01-01

    .... Flexible micromanipulator probes developed for probing waveguides. (5) Doped nano-diamonds and nanoceramic lasers- optically transparent YAG were demonstrated, and yttrium aluminum perovskite (YAP...

  12. Support vector machine to predict diesel engine performance and emission parameters fueled with nano-particles additive to diesel fuel

    Science.gov (United States)

    Ghanbari, M.; Najafi, G.; Ghobadian, B.; Mamat, R.; Noor, M. M.; Moosavian, A.

    2015-12-01

    This paper studies the use of adaptive Support Vector Machine (SVM) to predict the performance parameters and exhaust emissions of a diesel engine operating on nanodiesel blended fuels. In order to predict the engine parameters, the whole experimental data were randomly divided into training and testing data. For SVM modelling, different values for radial basis function (RBF) kernel width and penalty parameters (C) were considered and the optimum values were then found. The results demonstrate that SVM is capable of predicting the diesel engine performance and emissions. In the experimental step, Carbon nano tubes (CNT) (40, 80 and 120 ppm) and nano silver particles (40, 80 and 120 ppm) with nanostructure were prepared and added as additive to the diesel fuel. Six cylinders, four-stroke diesel engine was fuelled with these new blended fuels and operated at different engine speeds. Experimental test results indicated the fact that adding nano particles to diesel fuel, increased diesel engine power and torque output. For nano-diesel it was found that the brake specific fuel consumption (bsfc) was decreased compared to the net diesel fuel. The results proved that with increase of nano particles concentrations (from 40 ppm to 120 ppm) in diesel fuel, CO2 emission increased. CO emission in diesel fuel with nano-particles was lower significantly compared to pure diesel fuel. UHC emission with silver nano-diesel blended fuel decreased while with fuels that contains CNT nano particles increased. The trend of NOx emission was inverse compared to the UHC emission. With adding nano particles to the blended fuels, NOx increased compared to the net diesel fuel. The tests revealed that silver & CNT nano particles can be used as additive in diesel fuel to improve complete combustion of the fuel and reduce the exhaust emissions significantly.

  13. Semiconductor Nano wires and Nano tubes: From Fundamentals to Diverse Applications

    International Nuclear Information System (INIS)

    Xiong, Q.; Grimes, C.A.; Zacharias, M.; Morral, A.F.; Hiruma, K.; Shen, G.

    2012-01-01

    Research in the field of semiconductor nano wires (SNWs) and nano tubes has been progressing into a mature subject with several highly interdisciplinary sub areas such as nano electronics, nano photonics, nano composites, bio sensing, optoelectronics, and solar cells. SNWs represent a unique system with novel properties associated to their one-dimensional (1D) structures. The fundamental physics concerning the formation of discrete 1D subbands, coulomb blockade effects, ballistic transport, and many-body phenomena in 1D nano wires and nano tubes provide a strong platform to explore the various scientific aspects in these nano structures. A rich variety of preparation methods have already been developed for generating well-controlled 1D nano structures and from a broad range of materials. The present special issue focuses on the recent development in the mechanistic understanding of the synthesis, the studies on electrical/optical properties of nano wires and their applications in nano electronics, nano photonics, and solar-energy harvesting. In this special issue, we have several invited review articles and contributed papers that are addressing current status of the fundamental issues related to synthesis and the diverse applications of semiconducting nano wires and nano tubes. One of the papers reviews the progress of the top-down approach of developing silicon-based vertically aligned nano wires to explore novel device architectures and integration schemes for nano electronics and clean energy applications. Another paper reviews the recent developments and experimental evidences of probing the confined optical and acoustic phonon in nonpolar semiconducting (Si and Ge) nano wires using Raman spectroscopy. The paper by K. Hiruma et al. spotlights the III semiconductor nano wires and demonstrates selective-area metal organic vapor phase epitaxy grown GaAs/In(Al)GaAs and InP/InAs/InP nano wires with heterojunctions along their axial and radial directions. The paper

  14. Nano-silver mediated polymerization of pyrrole: synthesis and gas sensing properties of polypyrrole (PPy)/Ag nano-composite.

    Science.gov (United States)

    Kate, Kunal H; Damkale, Shubhangi R; Khanna, P K; Jain, G H

    2011-09-01

    Thermal polymerization of pyrrole was performed using silver nitrate as source of silver ions followed by its conversion to Polypyrrole (PPy)/Ag nano-comoposites without using any external oxidizing agent or solvent. The formation of PPy was monitored by UV-Visible absorption spectroscopy showing a band at approximately 464 nm. XRD measurement confirmed characteristic peaks for face centered cubic (fcc) silver and presence of PPy at 2 theta of approximately 23 degrees suggesting the formation of PPy/Ag nanocomposite. Transmission electron microscopy (TEM) images showed non-aggregated spherical Ag nano-particles of about 5-10 nm. PPy/Ag thick film acts as a NH3 sensor at 100 degrees C, a H2S sensor at 250 degrees C and CO2 sensor at 350 degrees C. The thick films showed capability to recognize various gases at different operating temperature.

  15. Metal Oxide Nano structures: Synthesis, Properties, and Applications

    International Nuclear Information System (INIS)

    Xu, L. H.; Patil, D. S.; Yang, J.; Xiao, J.

    2015-01-01

    In recent years, nano structured materials have attracted wide attention due to their fascinating optical and electrical properties, which make these materials potentially suitable for applications in electronics, optics, photonics, and sensors. Some metal oxides show a wide variety of morphologies such as nano wires, nano rods, nano tubes, nano rings, and nano belts. Synthesis and investigation of these metal-oxide nano structures are beneficial not only for understanding the fundamental phenomena in low dimensional systems, but also for developing new-generation nano devices with high performance.

  16. Brain Diseases

    Science.gov (United States)

    The brain is the control center of the body. It controls thoughts, memory, speech, and movement. It regulates the function of many organs. When the brain is healthy, it works quickly and automatically. However, ...

  17. Nano-Ceramic Coated Plastics

    Science.gov (United States)

    Cho, Junghyun

    2013-01-01

    Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (nano-ceramic coatings (TiO2, ZnO) on plastic materials (silicone, Teflon, PET, etc.) that can possess both photocatalytic oxide properties and flexible plastic properties. Processing cost is low and it does not require any expensive equipment investment. Processing can be scalable to current manufacturing infrastructure.

  18. Nano-Electrochemistry and Nano-Electrografting with an Original Combined AFM-SECM

    Directory of Open Access Journals (Sweden)

    Ammar Ben Brahim

    2013-05-01

    Full Text Available This study demonstrates the advantages of the combination between atomic force microscopy and scanning electrochemical microscopy. The combined technique can perform nano-electrochemical measurements onto agarose surface and nano-electrografting of non-conducting polymers onto conducting surfaces. This work was achieved by manufacturing an original Atomic Force Microscopy-Scanning ElectroChemical Microscopy (AFM-SECM electrode. The capabilities of the AFM-SECM-electrode were tested with the nano-electrografting of vinylic monomers initiated by aryl diazonium salts. Nano-electrochemical and technical processes were thoroughly described, so as to allow experiments reproducing. A plausible explanation of chemical and electrochemical mechanisms, leading to the nano-grafting process, was reported. This combined technique represents the first step towards improved nano-processes for the nano-electrografting.

  19. Synthesis and characterization of nano hydroxyapatite using reverse micro emulsions as nano reactors

    International Nuclear Information System (INIS)

    Amin, S.; Siddique, T.

    2015-01-01

    In the present work reverse micro emulsion has been employed as nano reactors to synthesize nano crystalline Hydroxyapatite (HA). Two precursors; calcium and phosphate with different counter ions of each were used for the synthesis of HA at two different temperatures. To maintain the emulsified nano reactor, cyclohexane, TX-100 and 1-butanol including phosphate precursor was the continuous phase while aqueous Ca precursor solution was taken as the dispersed phase. Nano crystalline particles thus produced were evaluated on the basis of synthesis route, counter ions and temperature. It has been shown that emulsified nano reactors control the morphology, particle size and minimize phase transformation of HA. Characterizations of nano powder of HA are carried out using x-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), and scanning electron microscopy (SEM). HA crystallite size was found to be in the range of 20-25 nm whereas the morphology of nano particles changed from spheres to rods. (author)

  20. Nano-Electrochemistry and Nano-Electrografting with an Original Combined AFM-SECM

    Science.gov (United States)

    Ghorbal, Achraf; Grisotto, Federico; Charlier, Julienne; Palacin, Serge; Goyer, Cédric; Demaille, Christophe; Ben Brahim, Ammar

    2013-01-01

    This study demonstrates the advantages of the combination between atomic force microscopy and scanning electrochemical microscopy. The combined technique can perform nano-electrochemical measurements onto agarose surface and nano-electrografting of non-conducting polymers onto conducting surfaces. This work was achieved by manufacturing an original Atomic Force Microscopy-Scanning ElectroChemical Microscopy (AFM-SECM) electrode. The capabilities of the AFM-SECM-electrode were tested with the nano-electrografting of vinylic monomers initiated by aryl diazonium salts. Nano-electrochemical and technical processes were thoroughly described, so as to allow experiments reproducing. A plausible explanation of chemical and electrochemical mechanisms, leading to the nano-grafting process, was reported. This combined technique represents the first step towards improved nano-processes for the nano-electrografting. PMID:28348337

  1. Brain Aneurysm

    Science.gov (United States)

    A brain aneurysm is an abnormal bulge or "ballooning" in the wall of an artery in the brain. They are sometimes called berry aneurysms because they ... often the size of a small berry. Most brain aneurysms produce no symptoms until they become large, ...

  2. Brain Development

    Science.gov (United States)

    ... Become a Member Home Early Development & Well-Being Brain Development A child’s brain undergoes an amazing period of development from birth ... neural connections each second. The development of the brain is influenced by many factors, including a child’s ...

  3. Managing collaboration in the nanoManipulator

    DEFF Research Database (Denmark)

    Hudson, Thomas C.; Helser, Aren T.; Sonnenwald, Diane H.

    2004-01-01

    We designed, developed, deployed, and evaluated the Collaborative nanoManipulator (CnM), a distributed, collaborative virtual environment system supporting remote scientific collaboration between users of the nanoManipulator interface to atomic force microscopes. This paper describes the entire...

  4. Instrument platforms for nano liquid chromatography

    Czech Academy of Sciences Publication Activity Database

    Šesták, Jozef; Moravcová, Dana; Kahle, Vladislav

    2015-01-01

    Roč. 1421, NOV (2015), s. 2-17 ISSN 0021-9673 R&D Projects: GA MV VG20112015021 Institutional support: RVO:68081715 Keywords : nano liquid chromatography * splitless gradient generation * nano LC platforms Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.926, year: 2015 http://hdl.handle.net/11104/0250900

  5. Application of nano-packaging in aquatics

    Directory of Open Access Journals (Sweden)

    D Jafarpour

    2018-03-01

    Conclusion: With regard to aquatics high nutritional value and their important presence in diet one should think of a way to increase it's survivability and maintaining quality. For this, nano technology can help packaging aquatics. Nano can be applied considerably in food health and environment protection.

  6. Villem Nano, pedagoog ja haritlane / Villem Normak

    Index Scriptorium Estoniae

    Normak, Villem

    2009-01-01

    Matemaatikaõpetaja, koolijuhi Villem Nano elust ja tegevusest. 1. juulil 1919 käivitas Villem Nano Tallinna õpetajate seminari, millest on läbi mitme nime- ja staatusemuudatuse kujunenud välja tänane Tallinna Ülikool

  7. Dipole nano-laser: Theory and properties

    Energy Technology Data Exchange (ETDEWEB)

    Ghannam, T., E-mail: gtalal@hotmail.com [King Abdullah Institute for Nano-Technology, King Saud University, PO Box 2454, Riyadh 11451 (Saudi Arabia)

    2014-03-31

    In this paper we outline the main quantum properties of the system of nano-based laser called Dipole Nano-Laser emphasizing mainly on its ability to produce coherent light and for different configurations such as different embedding materials and subjecting it to an external classical electric field.

  8. Biocompatibility and Toxicity of Nano biomaterials 2014

    International Nuclear Information System (INIS)

    Li, X.; Lee, S.Ch.; Zhang, Sh.; Akasaka, T.

    2014-01-01

    It is well known that nano materials have developed rapidly over the past few decades. Based on their unique physicochemical properties and special mechanical properties, nano materials have provided application possibility in many different fields. Currently, as nano biomaterials, they are widely used in various biomedical applications, such as drug delivery systems, tissue engineering, dental/bone implant, and biosensors. For example, nano biomaterials have been used in tissue engineering because of their satisfactory bioactivity, high mechanical properties, and large surface area to adsorb specific proteins. Many kinds of nano biomaterials are used to prepare composite scaffolds to get better biocompatibility and higher ability in repairing specific tissues. Several antibacterial metallic nano biomaterials are used to coat implant surfaces to improve the speed of healing fractures. In addition, lots of nano biomaterials have the potential to break the limitations of the traditional delivery systems. They can load larger amount of drugs and provide stable drug release for long time at the targeted sites, such as tumors. Moreover, they can combine with polymers to furnish simultaneous drug delivery systems with the controllable release rate. Besides these applications, more and more nano biomaterials show great potential to be applied as highly sensitive biosensors because they have higher ability in loading firmly or interacting completely with recognition aptamers.

  9. CZT nanoRAIDER_VFG Factsheet

    Energy Technology Data Exchange (ETDEWEB)

    James, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Bolotnikov, A. E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Cui, Yonggang [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-01-15

    Brookhaven National Laboratory (BNL) is working with FLIR System Inc., the manufacturer of the nanoRAIDER, to design a handheld device based on a position-sensitive virtual Frisch-grid (VFG) Cadmium-Zinc-Telluride (CdZnTe or CZT) detector array (with 1% or better energy resolution). The new device called nanoRAIDER VFG will be an improvement to the current nanoRAIDER, which is a compact gamma-ray detection instrument manufactured by FLIR Systems Inc. that employs relatively lower-performing CZT hemispheric detectors (i.e., 3%-FWHM CZT detectors). The nanoRAIDER will significantly improve the accuracy while maintaining similar efficiency, as compared to the nanoRAIDER, for in-field analysis of nuclear materials and detection of undeclared activities during inspections conducted by the International Atomic Energy Agency (IAEA). Since the nanoRAIDER is currently used by the IAEA as part of its Complementary Access toolkit, a relatively quick acceptance of the nanoRAIDER VFG for safeguards is anticipated. The nanoRAIDER VFG will help address several items listed in the IAEA’s Long-Term R&D Plan that could enhance the abilities to detect undeclared nuclear material and activities.

  10. Left Brain. Right Brain. Whole Brain

    Science.gov (United States)

    Farmer, Lesley S. J.

    2004-01-01

    As the United States student population is becoming more diverse, library media specialists need to find ways to address these distinctive needs. However, some of these differences transcend culture, touching on variations in the brain itself. Most people have a dominant side of the brain, which can affect their personality and learning style.…

  11. The nano-BIon in nanostructure

    Energy Technology Data Exchange (ETDEWEB)

    Sepehri, Alireza, E-mail: alireza.sepehri@uk.ac.ir [Nano Research Center of the Ferdowsi University, Mashhad (Iran, Islamic Republic of); Faculty of Physics, Shahid Bahonar University, P.O. Box 76175, Kerman (Iran, Islamic Republic of)

    2016-04-01

    Recently, some authors have considered the superconductivity in nano-cubes and shown that by decreasing the size of these systems, superconductivity order parameter increases. In this research, we show that the same result can be obtained in a nano-BIon which is a configuration of two layers of cuprates connected by an electronic tube. This tube is a channel for transporting energy and matter inside a superconductor and acts as a wormhole in this system. This wormhole-like-tube is formed by decreasing the separation distance between layers of nano-cuprate and enhancing the cooper hopping pairing between layers. We estimate the critical temperature of superconductor and find that it depends on the size of nano-BIon and coupling between atoms in a layer. Also, we observe that external magnetic field generates a new tube which causes losing the energy density of nano-BIon between two layers and decreasing critical temperature of superconductor.

  12. Issues in nano technologies for Australia

    International Nuclear Information System (INIS)

    Tegart, G.

    2007-01-01

    The Australian Government in late 2005 created a National Nano technology Taskforce that produced a paper, 'Options for a National Nano technology Strategy', in November last year. As an input to the National Nano technology Strategy Taskforce, in early 2006 the National Academies Forum was contracted by the Department of Industry, Tourism and Resources to produce a report Environmental, Social, Legal and Ethical Aspects of the Development of Nano technologies in Australia (which is available at www.naf.org.au/symposia). The report drew on the expertise of Fellows from the four academies in workshops in Melbourne and Sydney and from discussions with other experts, and expressed its outcomes as a set of opinions to assist in developing guidelines for a National Nano technology Strategy

  13. Brain Basics: Know Your Brain

    Science.gov (United States)

    ... however, the brain is beginning to relinquish its secrets. Scientists have learned more about the brain in ... through the activity of these lobes. At the top of each temporal lobe is an area responsible ...

  14. Why nano-oxidation with carbon nanotube probes is so stable: II. Bending behaviour of CNT probes during nano-oxidation

    International Nuclear Information System (INIS)

    Kuramochi, H; Tokizaki, T; Ando, K; Yokoyama, H; Dagata, J A

    2007-01-01

    Part I demonstrated that nano-oxidation in the dynamic-force mode was enhanced by the use of conductive carbon nanotube (CNT) probes. Fabrication of oxide nanostructures using CNT probes benefited not only from the smaller tip apex compared to conventional probes but from improved operational stability over a wide range of exposure conditions primarily due to the hydrophobic nature of the CNT. Here we investigate the bending response of CNT probes to electrostatic and meniscus forces during nano-oxidation. We conclude that bending of the CNT introduces an additional cushion in the combined cantilever-probe deflection system, thus improving overall stability of the tip-sample junction during nano-oxidation

  15. HIT`91 (prospective, co-operative study for the treatment of malignant brain tumors in childhood): accuracy and acute toxicity of the irradiation of the craniospinal axis

    Energy Technology Data Exchange (ETDEWEB)

    Kortmann, R.D.; Timmermann, B.; Bamberg, M. [Tuebingen Univ. (Germany). Dept. of Radiotherapy; Kuehl, J. [Wuerzburg Univ. (Germany). Children`s Hospital; Willich, N. [Muenster Univ. (Germany). Dept. of Radiotherapy; Flentje, M. [Wuerzburg Univ. (Germany). Dept. of Radiotherapy; Meisner, C. [Tuebingen Univ. (Germany). Inst. for Medical Information Processing

    1999-04-01

    Background: It was the aim of the quality control program of the randomized trial HIT `91 (intensive chemotherapy before irradiation versus maintenance chemotherapy after irradiation) to assess prospectively the quality of neuroaxis irradiation with respect to the protocol guidelines and to evaluate acute toxicity with respect to treatment arm. Patients, Materials and Methods: Data of 134 patients undergoing irradiation of the craniospinal axis were available. Positioning aids, shielding techniques, treatment machines, choice of energy, total dose and fractionation were evaluated. A total of 651 simulation and verification films were analyzed to assess the coverage of the clinical target volume (whole brain, posterior fossa, sacral nerve roots) and deviations of field alignment between simulation and verification of first treatment. Field matching between whole brain and adjacent cranial spinal fields was analyzed with respect to site and width of junction. Acute maximal side effects were evaluated according to a modified WHO score for neurotoxicity, infections, skin, mucosa and myelotoxicity. Results: In 91.3% of patients contemporary positioning aids and individualized shielding techniques were used to assure a reproducible treatment. In 98 patients (73.1%) linear accelerators and in 36 patients (26.8%) {sup 60}Cobalt machines were used. Single and total dose were administered according to the protocol guidelines in more than 90% of patients. In 20.2% of patients the cribriform plate, in 1.4% the middle cranial fossa and in 21.1% the posterior fossa and in 4.5% the 2nd sacral segment were incompletely encompassed by the treatment portals. Ninety-five percent of deviations of field alignment were less than 13.0 mm (whole brain) and 12 mm (cranial spinal field) with a random error between 4.9 and 7.6 mm (whole brain) and 6.9 mm and 9.9 mm (spinal canal), respectively. In 77.5% of patients the junctions between whole brain and cranial spinal fields were placed

  16. Nano Sensing and Energy Conversion Using Surface Plasmon Resonance (SPR

    Directory of Open Access Journals (Sweden)

    Iltai (Isaac Kim

    2015-07-01

    Full Text Available Nanophotonic technique has been attracting much attention in applications of nano-bio-chemical sensing and energy conversion of solar energy harvesting and enhanced energy transfer. One approach for nano-bio-chemical sensing is surface plasmon resonance (SPR imaging, which can detect the material properties, such as density, ion concentration, temperature, and effective refractive index in high sensitivity, label-free, and real-time under ambient conditions. Recent study shows that SPR can successfully detect the concentration variation of nanofluids during evaporation-induced self-assembly process. Spoof surface plasmon resonance based on multilayer metallo-dielectric hyperbolic metamaterials demonstrate SPR dispersion control, which can be combined with SPR imaging, to characterize high refractive index materials because of its exotic optical properties. Furthermore, nano-biophotonics could enable innovative energy conversion such as the increase of absorption and emission efficiency and the perfect absorption. Localized SPR using metal nanoparticles show highly enhanced absorption in solar energy harvesting. Three-dimensional hyperbolic metamaterial cavity nanostructure shows enhanced spontaneous emission. Recently ultrathin film perfect absorber is demonstrated with the film thickness is as low as ~1/50th of the operating wavelength using epsilon-near-zero (ENZ phenomena at the wavelength close to SPR. It is expected to provide a breakthrough in sensing and energy conversion applications using the exotic optical properties based on the nanophotonic technique.

  17. Nano-material aspects of shock absorption in bone joints.

    Science.gov (United States)

    Tributsch, H; Copf, F; Copf, P; Hindenlang, U; Niethard, F U; Schneider, R

    2010-01-01

    This theoretical study is based on a nano-technological evaluation of the effect of pressure on the composite bone fine structure. It turned out, that the well known macroscopic mechano-elastic performance of bones in combination with muscles and tendons is just one functional aspect which is critically supported by additional micro- and nano- shock damping technology aimed at minimising local bone material damage within the joints and supporting spongy bone material. The identified mechanisms comprise essentially three phenomena localised within the three-dimensional spongy structure with channels and so called perforated flexible tensulae membranes of different dimensions intersecting and linking them. Kinetic energy of a mechanical shock may be dissipated within the solid-liquid composite bone structure into heat via the generation of quasi-chaotic hydromechanic micro-turbulence. It may generate electro-kinetic energy in terms of electric currents and potentials. And the resulting specific structural and surface electrochemical changes may induce the compressible intra-osseal liquid to build up pressure dependent free chemical energy. Innovative bone joint prostheses will have to consider and to be adapted to the nano-material aspects of shock absorption in the operated bones.

  18. The battle of "nano" paclitaxel.

    Science.gov (United States)

    Sofias, Alexandros Marios; Dunne, Michael; Storm, Gert; Allen, Christine

    2017-12-01

    Paclitaxel (PTX) is one of the three most widely used chemotherapeutic agents, together with doxorubicin and cisplatin, and is first or second line treatment for several types of cancers. In 2000, Taxol, the conventional formulation of PTX, became the best-selling cancer drug of all time with annual sales of 1.6 billion. In 2005, the introduction of the albumin-based formulation of PTX, known as Abraxane, ended Taxol's monopoly of the PTX market. Abraxane's ability to push the Taxol innovator and generic formulations aside attracted fierce competition amongst competitors worldwide to develop their own unique, new and improved formulation of PTX. At this time there are at least 18 companies focused on pre-clinical and/or clinical development of nano-formulations of PTX. These pharmaceutical companies are investing substantial capital to capture a share of the lucrative global PTX market. It is hoped that any formulation that dominates the market will result in tangible benefits to patients in terms of both survival and quality of life. Given all of this activity, here we address the question: Who is going to win the battle of "nano" paclitaxel? Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Dietary 2'-Fucosyllactose Enhances Operant Conditioning and Long-Term Potentiation via Gut-Brain Communication through the Vagus Nerve in Rodents.

    Directory of Open Access Journals (Sweden)

    Enrique Vazquez

    Full Text Available 2´-fucosyllactose (2´-FL is an abundant human milk oligosaccharide (HMO in human milk with diverse biological effects. We recently reported ingested 2´-FL stimulates central nervous system (CNS function, such as hippocampal long term potentiation (LTP and learning and memory in rats. Conceivably the effect of 2´-FL on CNS function may be via the gut-brain axis (GBA, specifically the vagus nerve, and L-fucose (Fuc may play a role. This study had two aims: (1 determine if the effect of ingested 2´-FL on the modulation of CNS function is dependent on the integrity of the molecule; and (2 confirm if oral 2´-FL modified hippocampal LTP and associative learning related skills in rats submitted to bilateral subdiaphragmatic vagotomy. Results showed that 2´-FL but not Fuc enhanced LTP, and vagotomy inhibited the effects of oral 2´-FL on LTP and associative learning related paradigms. Taken together, the data show that dietary 2´-FL but not its Fuc moiety affects cognitive domains and improves learning and memory in rats. This effect is dependent on vagus nerve integrity, suggesting GBA plays a role in 2´-FL-mediated cognitive benefits.

  20. A Pilot Study of the Effects of Mindfulness-Based Stress Reduction on Post-traumatic Stress Disorder Symptoms and Brain Response to Traumatic Reminders of Combat in Operation Enduring Freedom/Operation Iraqi Freedom Combat Veterans with Post-traumatic Stress Disorder.

    Science.gov (United States)

    Bremner, James Douglas; Mishra, Sanskriti; Campanella, Carolina; Shah, Majid; Kasher, Nicole; Evans, Sarah; Fani, Negar; Shah, Amit Jasvant; Reiff, Collin; Davis, Lori L; Vaccarino, Viola; Carmody, James

    2017-01-01

    Brain imaging studies in patients with post-traumatic stress disorder (PTSD) have implicated a circuitry of brain regions including the medial prefrontal cortex, amygdala, hippocampus, parietal cortex, and insula. Pharmacological treatment studies have shown a reversal of medial prefrontal deficits in response to traumatic reminders. Mindfulness-based stress reduction (MBSR) is a promising non-pharmacologic approach to the treatment of anxiety and pain disorders. The purpose of this study was to assess the effects of MBSR on PTSD symptoms and brain response to traumatic reminders measured with positron-emission tomography (PET) in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) combat veterans with PTSD. We hypothesized that MBSR would show increased prefrontal response to stress and improved PTSD symptoms in veterans with PTSD. Twenty-six OEF/OIF combat veterans with PTSD who had recently returned from a combat zone were block randomized to receive eight sessions of MBSR or present-centered group therapy (PCGT). PTSD patients underwent assessment of PTSD symptoms with the Clinician-Administered PTSD Scale (CAPS), mindfulness with the Five Factor Mindfulness Questionnaire (FFMQ) and brain imaging using PET in conjunction with exposure to neutral and Iraq combat-related slides and sound before and after treatment. Nine patients in the MBSR group and 8 in the PCGT group completed all study procedures. Post-traumatic stress disorder patients treated with MBSR (but not PCGT) had an improvement in PTSD symptoms measured with the CAPS that persisted for 6 months after treatment. MBSR also resulted in an increase in mindfulness measured with the FFMQ. MBSR-treated patients had increased anterior cingulate and inferior parietal lobule and decreased insula and precuneus function in response to traumatic reminders compared to the PCGT group. This study shows that MBSR is a safe and effective treatment for PTSD. Furthermore, MBSR treatment is associated with

  1. A Pilot Study of the Effects of Mindfulness-Based Stress Reduction on Post-traumatic Stress Disorder Symptoms and Brain Response to Traumatic Reminders of Combat in Operation Enduring Freedom/Operation Iraqi Freedom Combat Veterans with Post-traumatic Stress Disorder

    Directory of Open Access Journals (Sweden)

    James Douglas Bremner

    2017-08-01

    Full Text Available ObjectiveBrain imaging studies in patients with post-traumatic stress disorder (PTSD have implicated a circuitry of brain regions including the medial prefrontal cortex, amygdala, hippocampus, parietal cortex, and insula. Pharmacological treatment studies have shown a reversal of medial prefrontal deficits in response to traumatic reminders. Mindfulness-based stress reduction (MBSR is a promising non-pharmacologic approach to the treatment of anxiety and pain disorders. The purpose of this study was to assess the effects of MBSR on PTSD symptoms and brain response to traumatic reminders measured with positron-emission tomography (PET in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF combat veterans with PTSD. We hypothesized that MBSR would show increased prefrontal response to stress and improved PTSD symptoms in veterans with PTSD.MethodTwenty-six OEF/OIF combat veterans with PTSD who had recently returned from a combat zone were block randomized to receive eight sessions of MBSR or present-centered group therapy (PCGT. PTSD patients underwent assessment of PTSD symptoms with the Clinician-Administered PTSD Scale (CAPS, mindfulness with the Five Factor Mindfulness Questionnaire (FFMQ and brain imaging using PET in conjunction with exposure to neutral and Iraq combat-related slides and sound before and after treatment. Nine patients in the MBSR group and 8 in the PCGT group completed all study procedures.ResultsPost-traumatic stress disorder patients treated with MBSR (but not PCGT had an improvement in PTSD symptoms measured with the CAPS that persisted for 6 months after treatment. MBSR also resulted in an increase in mindfulness measured with the FFMQ. MBSR-treated patients had increased anterior cingulate and inferior parietal lobule and decreased insula and precuneus function in response to traumatic reminders compared to the PCGT group.ConclusionThis study shows that MBSR is a safe and effective treatment for PTSD

  2. Laser nano-manufacturing: state of the art and challenges

    NARCIS (Netherlands)

    Li, L.; Hong, M.; Schmidt, M.; Zhong, M.; Mashe, A.; Huis in 't veld, A.J.; Kovalenko, V.

    2011-01-01

    This paper provides an overview of advances in laser based nano-manufacturing technologies including surface nano-structure manufacturing, production of nano materials (nanoparticles, nanotubes and nanowires) and 3D nano-structures manufacture through multiple layer additive techniques and

  3. [Preparation of nano-nacre artificial bone].

    Science.gov (United States)

    Chen, Jian-ting; Tang, Yong-zhi; Zhang, Jian-gang; Wang, Jian-jun; Xiao, Ying

    2008-12-01

    To assess the improvements in the properties of nano-nacre artificial bone prepared on the basis of nacre/polylactide acid composite artificial bone and its potential for clinical use. The compound of nano-scale nacre powder and poly-D, L-lactide acid (PDLLA) was used to prepare the cylindrical hollow artificial bone, whose properties including raw material powder scale, pore size, porosity and biomechanical characteristics were compared with another artificial bone made of micron-scale nacre powder and PDLLA. Scanning electron microscope showed that the average particle size of the nano-nacre powder was 50.4-/+12.4 nm, and the average pore size of the artificial bone prepared using nano-nacre powder was 215.7-/+77.5 microm, as compared with the particle size of the micron-scale nacre powder of 5.0-/+3.0 microm and the pore size of the resultant artificial bone of 205.1-/+72.0 microm. The porosities of nano-nacre artificial bone and the micron-nacre artificial bone were (65.4-/+2.9)% and (53.4-/+2.2)%, respectively, and the two artificial bones had comparable compressive strength and Young's modulus, but the flexural strength of the nano-nacre artificial bone was lower than that of the micro-nacre artificial bone. The nano-nacre artificial bone allows better biodegradability and possesses appropriate pore size, porosity and biomechanical properties for use as a promising material in bone tissue engineering.

  4. Nano crystals for Electronic and Optoelectronic Applications

    International Nuclear Information System (INIS)

    Zhu, T.; Cloutier, S.G.; Ivanov, I; Knappenberger Jr, K.L.; Robel, I.; Zhang, F

    2012-01-01

    Electronic and optoelectronic devices, from computers and smart cell phones to solar cells, have become a part of our life. Currently, devices with featured circuits of 45 nm in size can be fabricated for commercial use. However, further development based on traditional semiconductor is hindered by the increasing thermal issues and the manufacturing cost. During the last decade, nano crystals have been widely adopted in various electronic and optoelectronic applications. They provide alternative options in terms of ease of processing, low cost, better flexibility, and superior electronic/optoelectronic properties. By taking advantage of solution-processing, self-assembly, and surface engineering, nano crystals could serve as new building blocks for low-cost manufacturing of flexible and large area devices. Tunable electronic structures combined with small exciton binding energy, high luminescence efficiency, and low thermal conductivity make nano crystals extremely attractive for FET, memory device, solar cell, solid-state lighting/display, photodetector, and lasing applications. Efforts to harness the nano crystal quantum tunability have led to the successful demonstration of many prototype devices, raising the public awareness to the wide range of solutions that nano technology can provide for an efficient energy economy. This special issue aims to provide the readers with the latest achievements of nano crystals in electronic and optoelectronic applications, including the synthesis and engineering of nano crystals towards the applications and the corresponding device fabrication, characterization and computer modeling.

  5. Phosphorylated nano-diamond/ Polyimide Nanocomposites

    International Nuclear Information System (INIS)

    Beyler-Çiǧil, Asli; Çakmakçi, Emrah; Kahraman, Memet Vezir

    2014-01-01

    In this study, a novel route to synthesize polyimide (PI)/phosphorylated nanodiamond films with improved thermal and mechanical properties was developed. Surface phosphorylation of nano-diamond was performed in dichloromethane. Phosphorylation dramatically enhanced the thermal stability of nano-diamond. Poly(amic acid) (PAA), which is the precursor of PI, was successfully synthesized with 3,3',4,4'-Benzophenonetetracarboxylic dianhydride (BTDA) and 4,4'-oxydianiline (4,4'-ODA) in the solution of N,N- dimethylformamide (DMF). Pure BTDA-ODA polyimide films and phosphorylated nanodiamond containing BTDA-ODA PI films were prepared. The PAA displayed good compatibility with phosphorylated nano-diamond. The morphology of the polyimide (PI)/phosphorylated nano-diamond was characterized by scanning electron microscopy (SEM). Chemical structure of polyimide and polyimide (PI)/phosphorylated nano-diamond was characterized by FTIR. SEM and FTIR results showed that the phosphorylated nano-diamond was successfully prepared. Thermal properties of the polyimide (PI)/phosphorylated nanodiamond was characterized by thermogravimetric analysis (TGA). TGA results showed that the thermal stability of (PI)/phosphorylated nano-diamond film was increased

  6. Design and Simulation of Nano Wire FET

    Directory of Open Access Journals (Sweden)

    M. Anil Kumar

    2017-06-01

    Full Text Available As the era of classical planar metal-oxide-semiconductor field-effect transistors (MOSFETs comes to an end, the semiconductor industry is beginning to adopt 3D device architectures, such as FinFETs, starting at the 22 nm technology node. Since physical limits such as short channel effect (SCE and self-heating may dominate, it may be difficult to scale Si FinFET below 10 nm. In this regard, transistors with different materials, geometries, or operating principles may help. For example, gate has excellent electrostatic control over 2D thin film channel with planar geometry and 1D nanowire (NW channel with gate-all-around (GAA geometry to reduce SCE. High carrier mobility of single wall carbon nanotube (SWNT or III-V channels may reduce VDD to reduce power consumption. Therefore, as channel of transistor, 2D thin film of array SWNTs and 1D III-V multi NWs are promising for sub 10 nm technology nodes. To simulate these devices, accurate modelling and design based on gate-material are necessary to assess their performance limits, since cross-sections of the multi-gate NWFETs are expected to be a few nano-meters wide in their ultimate scaling. In this paper we have explored the use of SILVACO with different materials for simulating and studying the short channel behaviour of nanowire FETs.

  7. High Performance Nano-Ceria Electrodes for Solid Oxide Cells

    DEFF Research Database (Denmark)

    Graves, Christopher R.; Martinez Aguilera, Lev; Sudireddy, Bhaskar Reddy

    2016-01-01

    forming the active surfaces on a porous backbone with embedded electronic current collector material, yielding one of the highest performances reported for an electrode that operates either on fuel or oxidant. The second is a nano-Ce0.9Gd0.1O2-δ thin film prepared by spin-coating, which provides......In solid oxide electrochemical cells, the conventional Ni-based fuel-electrodes provide high electrocatalytic activity but they are often a major source of long-term performance degradation due to carbon deposition, poisoning of reaction sites, Ni mobility, etc. Doped-ceria is a promising mixed...

  8. Brain glycogen

    DEFF Research Database (Denmark)

    Obel, Linea Lykke Frimodt; Müller, Margit S; Walls, Anne B

    2012-01-01

    Glycogen is a complex glucose polymer found in a variety of tissues, including brain, where it is localized primarily in astrocytes. The small quantity found in brain compared to e.g., liver has led to the understanding that brain glycogen is merely used during hypoglycemia or ischemia....... In this review evidence is brought forward highlighting what has been an emerging understanding in brain energy metabolism: that glycogen is more than just a convenient way to store energy for use in emergencies-it is a highly dynamic molecule with versatile implications in brain function, i.e., synaptic...... activity and memory formation. In line with the great spatiotemporal complexity of the brain and thereof derived focus on the basis for ensuring the availability of the right amount of energy at the right time and place, we here encourage a closer look into the molecular and subcellular mechanisms...

  9. Environmental risk assessment of engineered nano-SiO2 , nano iron oxides, nano-CeO2 , nano-Al2 O3 , and quantum dots.

    Science.gov (United States)

    Wang, Yan; Nowack, Bernd

    2018-05-01

    Many research studies have endeavored to investigate the ecotoxicological hazards of engineered nanomaterials (ENMs). However, little is known regarding the actual environmental risks of ENMs, combining both hazard and exposure data. The aim of the present study was to quantify the environmental risks for nano-Al 2 O 3 , nano-SiO 2 , nano iron oxides, nano-CeO 2 , and quantum dots by comparing the predicted environmental concentrations (PECs) with the predicted-no-effect concentrations (PNECs). The PEC values of these 5 ENMs in freshwaters in 2020 for northern Europe and southeastern Europe were taken from a published dynamic probabilistic material flow analysis model. The PNEC values were calculated using probabilistic species sensitivity distribution (SSD). The order of the PNEC values was quantum dots nano-CeO 2  nano iron oxides nano-Al 2 O 3  nano-SiO 2 . The risks posed by these 5 ENMs were demonstrated to be in the reverse order: nano-Al 2 O 3  > nano-SiO 2  > nano iron oxides > nano-CeO 2  > quantum dots. However, all risk characterization values are 4 to 8 orders of magnitude lower than 1, and no risk was therefore predicted for any of the investigated ENMs at the estimated release level in 2020. Compared to static models, the dynamic material flow model allowed us to use PEC values based on a more complex parameterization, considering a dynamic input over time and time-dependent release of ENMs. The probabilistic SSD approach makes it possible to include all available data to estimate hazards of ENMs by considering the whole range of variability between studies and material types. The risk-assessment approach is therefore able to handle the uncertainty and variability associated with the collected data. The results of the present study provide a scientific foundation for risk-based regulatory decisions of the investigated ENMs. Environ Toxicol Chem 2018;37:1387-1395. © 2018 SETAC. © 2018 SETAC.

  10. Nano-nutrition of chicken embryos

    DEFF Research Database (Denmark)

    Sawosz, Filip; Pineda, Lane Manalili; Hotowy, Anna

    2013-01-01

    It has been suggested that the quantity and quality of nutrients stored in the egg might not be optimal for the fast rate of chicken embryo development in modern broilers, and embryos could be supplemented with nutrients by in ovo injection. Recent experiments showed that in ovo feeding reduces...... broiler eggs was randomly divided into a Control group without injection and injected groups with hydrocolloids of Nano-Ag, ATP or a complex of Nano-Ag and ATP (Nano-Ag/ATP). The embryos were evaluated on day 20 of incubation. The results indicate that the application of ATP to chicken embryos increases...

  11. Micro Nano Replication Processes and Applications

    CERN Document Server

    Kang, Shinill

    2012-01-01

    This book is an introduction to the fundamentals and processes for micro and nano molding for plastic components. In addition to the basics, the book covers applications details and examples. The book helps both students and professionals to understand and work with the growing tools of molding and uses for micro and nano-sized plastic parts.Provides a comprehensive presentation on fundamentals and practices of manufacturing for micro / nano sized plastics partsCovers a relatively new but fast-growing field that is impacting any industry using plastic parts in their products (electronics, tele

  12. VMESNIK ZA DALJINSKO VODENJE NANO-ROBOTA

    OpenAIRE

    Kocmut, Silvester

    2015-01-01

    V diplomskem delu je predstavljen programski uporabniški vmesnik za vodenje realnega nano-robota. Uporabniški vmesnik omogoča neposredno krmiljenje nano-robota. Realni nano-robot ima pet translacijskih osi, omogoča tudi montažo prijemala. Osi delujejo na osnovi piezoelektričnih aktuatorjev. Izhod iz inkrementalnih dajalnikov nam da povratno informacijo o gibanju. Uporabniški vmesnik omogoča ročno vodenje preko navideznih gumbov za vseh pet osi ter vodenje preko ročne ure EZ430-Chronos. Krmilj...

  13. Nano controllers characterization under radiation

    International Nuclear Information System (INIS)

    Bezerra, F.; Barde, S.; Carayon, J.L.; Sarthou, M.

    1999-01-01

    4 commercial nano-controllers (PIC16LC84, PIC16C73A, PIC16C76 and ST62E25) from MICROCHIP and SGS-Thomson have been characterized under heavy-ions, protons and total dose. The preliminary results show that PIC16LC84 has to be banned from the selection because it can not sustain high cumulated dose (its Idd begins to shift at 6 krads) and that its E 2 PROM code memory is too sensitive to SEU (single event upset). The 3 PICs have been tested with heavy-ions, the results show that they are sensible to upsets and latch-up, nevertheless no latch-up has been observed under proton irradiation. The sensitivity to latch-up does not matter a lot because PICs consume very little and it is planned to implement them in a tolerant design. (A.C.)

  14. Intelligent micro reactors. ''Nano firms''

    International Nuclear Information System (INIS)

    Pileni, M.P.; CEA Centre d'Etudes de Saclay, 91 - Gif-sur-Yvette

    1998-01-01

    A new synthesis method of CdS has been carried out. It is based on the use of inverse micellar systems. These micellae have an important property which is used here: when two droplets collide, they can join during a short moment and divide again, creating two new droplets identical to the first ones but which have indeed mixed their respective contents. The mixture of two inverse micellae (each containing a reagent) can lead to a chemical reaction, reduction or co-precipitation. Semi-conductor crystals of CdS have thus been synthesized. They are nano crystals. Their size is indeed limited because the droplets size limit the crystals growth which stabilize and stay inside the droplet. (O.M.)

  15. Fabrication of high-aspect-ratio nano structures using a nano x-ray shadow mask

    International Nuclear Information System (INIS)

    Kim, Yong Chul; Lee, Seung S

    2008-01-01

    This paper describes a novel method for the fabrication of high-aspect-ratio nano structures (HAR-nano structures) using a nano x-ray shadow mask and deep x-ray lithography (DXRL). The nano x-ray shadow mask is fabricated by depositing an x-ray absorber layer (Au, 3 µm) onto the back side of a nano shadow mask. The nano shadow mask is produced with nano-sized apertures whose dimensions are reduced to several tens of nanometers by the accumulation of low-stress silicon nitride (Si x N y ) using the LPCVD process on the shadow mask. A shadow mask containing apertures with a size of 1 µm is fabricated on a bulk micromachined Si x N y membrane. The thickness of an absorber layer must be in the range of several tens of micrometers in order to obtain a contrast of more than 100 for the conventional DXRL process at the Pohang Light Source (PLS). However, a 3 µm thick absorber layer can provide a sufficient contrast if the modified DXRL of the central beam-stop method is used, which blocks high-energy x-rays. A nano shadow mask with 30 nm sized apertures is fabricated and a nano x-ray shadow mask with 250 nm sized apertures is fabricated by depositing a 3 µm thick absorber layer on a nano shadow mask with 500 nm sized apertures. HAR-nano structures (circles with a diameter of 420 nm and lines with a width of 274 nm) with aspect ratios of over 10:1 on a 3.2 µm SU-8 are successfully fabricated by using the nano x-ray shadow mask and the central beam-stop method

  16. Application of emission CT on nano-robot radiation imaging tracing and isotope sign in nano-robot

    International Nuclear Information System (INIS)

    Wang Xuewu; Cheng Jianping; Kang Kejun

    2000-01-01

    Nano-technology has been a scientific and technical frontier with major trends foreseen in several disciplines. Nano-robot is the most remarkable imagination of the application of nano-technology. And it should be concerned of tracing technology along with nano-robot. The character of nano-robot is deeply analyzed, the development status of emission CT is integrated, and the application of emission CT on nano-robot radiation imaging tracing is discussed. The isotope sign of nano-robot is especially calculated and analyzed

  17. AC dielectrophoresis alignment of single-walled carbon nano tubes (SWNTS) and palladium nano wires for hydrogen gas sensor

    International Nuclear Information System (INIS)

    Nur Ubaidah Saidin; Nur Ubaidah Saidin; Ying, K.K.; KKhuan, N.I.; Mohammad Hafizuddin Jumali

    2013-01-01

    Full-text: Using AC electric field, nano wires or nano tubes can be aligned, chained or accelerated in a direction parallel to the applied field, oriented or concentrated onto designated locations as well as dispersed in controlled manner under high efficiencies. In this work, systematic study on the alignment of nano wires/ nano tubes across the 3 μm-gaps between pairs of micro fabricated gold electrodes was carried out using AC dielectrophoresis technique. Densities and alignment of the nano wires/ nano tubes across the gaps of the electrodes were controlled by the applied AC field strengths and frequencies on the electrodes. Good alignments of SWNTs and Pd nano wires were achieved at an applied frequency of 5 MHz and a field strength as high as 25 V pp for Pd nano wires compared to only 2 V pp for SWNTs. The aligned nano wires/ nano tubes will be functioned as sensor elements for hydrogen gas sensing. (author)

  18. Nano medicine in Action: An Overview of Cancer Nano medicine on the Market and in Clinical Trials

    International Nuclear Information System (INIS)

    Wang, R.; Billone, P.S.; Mullett, W.M.

    2013-01-01

    Nano medicine, defined as the application of nano technology in the medical field, has the potential to significantly change the course of diagnostics and treatment of life-threatening diseases, such as cancer. In comparison with traditional cancer diagnostics and therapy, cancer nano medicine provides sensitive cancer detection and/or enhances treatment efficacy with significantly minimized adverse effects associated with standard therapeutics. Cancer nano medicine has been increasingly applied in areas including nano drug delivery systems, nano pharmaceuticals, and nano analytical contrast reagents in laboratory and animal model research. In recent years, the successful introduction of several novel nano medicine products into clinical trials and even onto the commercial market has shown successful outcomes of fundamental research into clinics. This paper is intended to examine several nano medicines for cancer therapeutics and/or diagnostics-related applications, to analyze the trend of nano medicine development, future opportunities, and challenges of this fast-growing area.

  19. Topodynamics of metastable brains

    Science.gov (United States)

    Tozzi, Arturo; Peters, James F.; Fingelkurts, Andrew A.; Fingelkurts, Alexander A.; Marijuán, Pedro C.

    2017-07-01

    The brain displays both the anatomical features of a vast amount of interconnected topological mappings as well as the functional features of a nonlinear, metastable system at the edge of chaos, equipped with a phase space where mental random walks tend towards lower energetic basins. Nevertheless, with the exception of some advanced neuro-anatomic descriptions and present-day connectomic research, very few studies have been addressing the topological path of a brain embedded or embodied in its external and internal environment. Herein, by using new formal tools derived from algebraic topology, we provide an account of the metastable brain, based on the neuro-scientific model of Operational Architectonics of brain-mind functioning. We introduce a ;topodynamic; description that shows how the relationships among the countless intertwined spatio-temporal levels of brain functioning can be assessed in terms of projections and mappings that take place on abstract structures, equipped with different dimensions, curvatures and energetic constraints. Such a topodynamical approach, apart from providing a biologically plausible model of brain function that can be operationalized, is also able to tackle the issue of a long-standing dichotomy: it throws indeed a bridge between the subjective, immediate datum of the naïve complex of sensations and mentations and the objective, quantitative, data extracted from experimental neuro-scientific procedures. Importantly, it opens the door to a series of new predictions and future directions of advancement for neuroscientific research.

  20. Indentation analysis of nano-particle using nano-contact mechanics models during nano-manipulation based on atomic force microscopy

    International Nuclear Information System (INIS)

    Daeinabi, Khadijeh; Korayem, Moharam Habibnejad

    2011-01-01

    Atomic force microscopy is applied to measure intermolecular forces and mechanical properties of materials, nano-particle manipulation, surface scanning and imaging with atomic accuracy in the nano-world. During nano-manipulation process, contact forces cause indentation in contact area between nano-particle and tip/substrate which is considerable at nano-scale and affects the nano-manipulation process. Several nano-contact mechanics models such as Hertz, Derjaguin–Muller–Toporov (DMT), Johnson–Kendall–Roberts–Sperling (JKRS), Burnham–Colton–Pollock (BCP), Maugis–Dugdale (MD), Carpick–Ogletree–Salmeron (COS), Pietrement–Troyon (PT), and Sun et al. have been applied as the continuum mechanics approaches at nano-scale. In this article, indentation depth and contact radius between tip and substrate with nano-particle for both spherical and conical tip shape during nano-manipulation process are analyzed and compared by applying theoretical, semiempirical, and empirical nano-contact mechanics models. The effects of adhesion force, as the main contrast point in different nano-contact mechanics models, on nano-manipulation analysis is investigated for different contact radius, and the critical point is discussed for mentioned models.

  1. High performance nano-composite technology development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Whung Whoe; Rhee, C. K.; Kim, S. J.; Park, S. D. [KAERI, Taejon (Korea, Republic of); Kim, E. K.; Jung, S. Y.; Ryu, H. J. [KRICT, Taejon (Korea, Republic of); Hwang, S. S.; Kim, J. K.; Hong, S. M. [KIST, Taejon (Korea, Republic of); Chea, Y. B. [KIGAM, Taejon (Korea, Republic of); Choi, C. H.; Kim, S. D. [ATS, Taejon (Korea, Republic of); Cho, B. G.; Lee, S. H. [HGREC, Taejon (Korea, Republic of)

    1999-06-15

    The trend of new material development are being to carried out not only high performance but also environmental attraction. Especially nano composite material which enhances the functional properties of components, extending the component life resulting to reduced the wastes and environmental contamination, has a great effect on various industrial area. The application of nano composite, depends on the polymer matrix and filler materials, has various application from semiconductor to medical field. In spite of nano composite merits, nano composite study are confined to a few special materials as a lab, scale because a few technical difficulties are still on hold. Therefore, the purpose of this study establishes the systematical planning to carried out the next generation projects on order to compete with other countries and overcome the protective policy of advanced countries with grasping over sea's development trends and our present status. (author).

  2. Handbook of nano-optics and nanophotonics

    CERN Document Server

    2013-01-01

    In the 1990s, optical technology and photonics industry developed fast, but further progress became difficult due to a fundamental limit of light known as the diffraction limit. This limit could be overcome using the novel technology of nano-optics or nanophotonics in which the size of the electromagnetic field is decreased down to the nanoscale and is used as a carrier for signal transmission, processing, and fabrication. Such a decrease beyond the diffraction limit is possible by using optical near-fields. The true nature of nano-optics and nanophotonics involves not only their abilities to meet the above requirements but also their abilities to realize qualitative innovations in photonic devices, fabrication techniques, energy conversion and information processing systems. The objective of this work is to review the innovations of optical science and technology by nano-optics and nanophotonics. While in conventional optical science and technology, light and matter are discussed separately, in nano-optics a...

  3. Nano Approaches to Modulate Host Cell Response

    Science.gov (United States)

    The Carolina Center of Cancer Nanotechnology Excellence (CCNE) is an NCI-funded multidisciplinary collaboration among a range of disciplines using nano approaches for cancer disease management and treatment.

  4. DyNano-2010, Book of abstracts

    International Nuclear Information System (INIS)

    Bjoemeholm, O.; Boutu, W.; Gauthier, D.; Xunyou, Ge; Xiaochi, Liu; Carre, B.; Merdji, H.; Winkler, M.; Harnes, J.; Saethre, L.J.; Boerve, K.J.

    2012-01-01

    The amazing progresses made in the recent years by the instrumentation in terms of spectral brightness of the X-ray sources (new synchrotron radiation facilities, X-ray Free Electron Lasers etc.), detection schemes (multi-channel analysis due to intensive use of position sensitive detectors, time-resolved techniques etc.) and production sources of clusters (pure and mixed, atomic and molecular clusters) and nano-particles permit nowadays highly accurate spectroscopic studies of more and more complex objects. There were dedicated sessions on the following topics: 1) recent progress in Nano-object's investigations, 2) synchrotron radiation based spectroscopic investigations of clusters and nano-particles, 3) Structure and properties of size-selected clusters, 4) electronic and nuclear decay of clusters, 5) new insights in structure and dynamics of complex species, and 6) clusters and nano-particles and new light sources. This document gathers only the abstracts of the papers

  5. MEMS and Nano-Technology Clean Room

    Data.gov (United States)

    Federal Laboratory Consortium — The MEMS and Nano-Technology Clean Room is a state-of-the-art, 800 square foot, Class 1000-capable facility used for development of micro and sub-micro scale sensors...

  6. Generation and characterization of nano aluminium powder ...

    Indian Academy of Sciences (India)

    TECS

    Generation and characterization of nano aluminium powder obtained through wire ... Department of Aerospace Engineering, Indian Institute of Technology. Madras, Chennai 600 .... pressure developed due to current flow (z-Pinch). Figure 2.

  7. Hydrogen Storage in Carbon Nano-materials

    International Nuclear Information System (INIS)

    David Eyler; Michel Junker; Emanuelle Breysse Carraboeuf; Laurent Allidieres; David Guichardot; Fabien Roy; Isabelle Verdier; Edward Mc Rae; Moulay Rachid Babaa; Gilles Flamant; David Luxembourg; Daniel Laplaze; Patrick Achard; Sandrine Berthon-Fabry; David Langohr; Laurent Fulcheri

    2006-01-01

    This paper presents the results of a French project related to hydrogen storage in carbon nano-materials. This 3 years project, co-funded by the ADEME (French Agency for the Environment and the Energy Management), aimed to assess the hydrogen storage capacity of carbon nano-materials. Four different carbon materials were synthesized and characterized in the frame of present project: - Carbon Nano-tubes; - Carbon Nano-fibres; - Carbon Aerogel; - Carbon Black. All materials tested in the frame of this project present a hydrogen uptake of less than 1 wt% (-20 C to 20 C). A state of the art of hydrogen storage systems has been done in order to determine the research trends and the maturity of the different technologies. The choice and design of hydrogen storage systems regarding fuel cell specifications has also been studied. (authors)

  8. Influence of Nano Silica on Alkyd Films

    DEFF Research Database (Denmark)

    Nikolic, Miroslav

    . The present work centers on the reinforcement of alkyd binders emulsified in water and used in exterior wood coatings with nano silica. Raman spectroscopy was used throughout the study to maintain the reproducibility of results as it was found that colloidal nano silica can increase or decrease the speed...... of alkyd curing affecting the tested mechanical properties. Hydrophilic, colloidal nano silica was seen to have limited effect in improving the mechanical properties due to problems in properly dispersing and attaining good surface interactions with the hydrophobic alkyd polymer. Efforts in increasing...... the interactions with the alkyd polymer while keeping the nano filler stable in the water phase did not show further improvements of mechanical properties. The best results in respect to mechanical properties, as measured under static and dynamic loading, were obtained with the use of hexamethyldisilazane treated...

  9. Micro and nano lasers for digital photonics

    NARCIS (Netherlands)

    Hill, M.T.; Oei, Y.S.; Zhu, Y.C.; Smit, M.K.

    2007-01-01

    The small size, low-power and high-speed of nano-lasers make them an attractive nonlinear element for digital photonics. Further miniaturization of lasers below the diffraction limit is required before digital photonics can compete with electronics.

  10. High performance nano-composite technology development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Whung Whoe; Rhee, C. K.; Kim, S. J.; Park, S. D. [KAERI, Taejon (Korea, Republic of); Kim, E. K.; Jung, S. Y.; Ryu, H. J. [KRICT, Taejon (Korea, Republic of); Hwang, S. S.; Kim, J. K.; Hong, S. M. [KIST, Taejon (Korea, Republic of); Chea, Y. B. [KIGAM, Taejon (Korea, Republic of); Choi, C. H.; Kim, S. D. [ATS, Taejon (Korea, Republic of); Cho, B. G.; Lee, S. H. [HGREC, Taejon (Korea, Republic of)

    1999-06-15

    The trend of new material development are being to carried out not only high performance but also environmental attraction. Especially nano composite material which enhances the functional properties of components, extending the component life resulting to reduced the wastes and environmental contamination, has a great effect on various industrial area. The application of nano composite, depends on the polymer matrix and filler materials, has various application from semiconductor to medical field. In spite of nano composite merits, nano composite study are confined to a few special materials as a lab, scale because a few technical difficulties are still on hold. Therefore, the purpose of this study establishes the systematical planning to carried out the next generation projects on order to compete with other countries and overcome the protective policy of advanced countries with grasping over sea's development trends and our present status. (author).

  11. High performance nano-composite technology development

    International Nuclear Information System (INIS)

    Kim, Whung Whoe; Rhee, C. K.; Kim, S. J.; Park, S. D.; Kim, E. K.; Jung, S. Y.; Ryu, H. J.; Hwang, S. S.; Kim, J. K.; Hong, S. M.; Chea, Y. B.; Choi, C. H.; Kim, S. D.; Cho, B. G.; Lee, S. H.

    1999-06-01

    The trend of new material development are being to carried out not only high performance but also environmental attraction. Especially nano composite material which enhances the functional properties of components, extending the component life resulting to reduced the wastes and environmental contamination, has a great effect on various industrial area. The application of nano composite, depends on the polymer matrix and filler materials, has various application from semiconductor to medical field. In spite of nano composite merits, nano composite study are confined to a few special materials as a lab, scale because a few technical difficulties are still on hold. Therefore, the purpose of this study establishes the systematical planning to carried out the next generation projects on order to compete with other countries and overcome the protective policy of advanced countries with grasping over sea's development trends and our present status. (author).

  12. Managing collaboration in the nanoManipulator

    DEFF Research Database (Denmark)

    Hudson, Thomas C.; Heiser, Aron T.; Sonnenwald, Diane H.

    2003-01-01

    We designed, developed, deployed, and evaluated the Collaborative nanoManipulator (CnM), a system supporting remote collaboration between users of the nanoManipulator interface to atomic force microscopes. To be accepted by users, the shared nanoManipulator application had to have the same high...... level of interactivity as the single user system and the application had to support a user's ability to interleave working privately and working collaboratively. This paper briefly describes the entire collaboration system, but focuses on the shared nanoManipulator application. Based on our experience...... developing the CnM, we present: a method of analyzing applications to characterize the requirements for sharing data between collaborating sites, examples of data structures that support collaboration, and guidelines for selecting appropriate synchronization and concurrency control schemes....

  13. Green chemistry by nano-catalysis

    KAUST Repository

    Polshettiwar, Vivek

    2010-01-01

    Nano-materials are important in many diverse areas, from basic research to various applications in electronics, biochemical sensors, catalysis and energy. They have emerged as sustainable alternatives to conventional materials, as robust high surface area heterogeneous catalysts and catalyst supports. The nano-sized particles increase the exposed surface area of the active component of the catalyst, thereby enhancing the contact between reactants and catalyst dramatically and mimicking the homogeneous catalysts. This review focuses on the use of nano-catalysis for green chemistry development including the strategy of using microwave heating with nano-catalysis in benign aqueous reaction media which offers an extraordinary synergistic effect with greater potential than these three components in isolation. To illustrate the proof-of-concept of this "green and sustainable" approach, representative examples are discussed in this article. © 2010 The Royal Society of Chemistry.

  14. Synthesis, Characterization and Application of Nano Lepidocrocite ...

    African Journals Online (AJOL)

    NICO

    Degradation of halogenated organic compounds using nanoparticles is one of the innovative ... way as the synthesis of nano zero-valent iron by using sodium .... +. −. 2и High. 2и Low. FWHM. Crystallite. /counts. /counts. /degree. /degree.

  15. The Spin Torque Lego - from spin torque nano-devices to advanced computing architectures

    Science.gov (United States)

    Grollier, Julie

    2013-03-01

    Spin transfer torque (STT), predicted in 1996, and first observed around 2000, brought spintronic devices to the realm of active elements. A whole class of new devices, based on the combined effects of STT for writing and Giant Magneto-Resistance or Tunnel Magneto-Resistance for reading has emerged. The second generation of MRAMs, based on spin torque writing : the STT-RAM, is under industrial development and should be out on the market in three years. But spin torque devices are not limited to binary memories. We will rapidly present how the spin torque effect also allows to implement non-linear nano-oscillators, spin-wave emitters, controlled stochastic devices and microwave nano-detectors. What is extremely interesting is that all these functionalities can be obtained using the same materials, the exact same stack, simply by changing the device geometry and its bias conditions. So these different devices can be seen as Lego bricks, each brick with its own functionality. During this talk, I will show how spin torque can be engineered to build new bricks, such as the Spintronic Memristor, an artificial magnetic nano-synapse. I will then give hints on how to assemble these bricks in order to build novel types of computing architectures, with a special focus on neuromorphic circuits. Financial support by the European Research Council Starting Grant NanoBrain (ERC 2010 Stg 259068) is acknowledged.

  16. Nano-tribology and materials in MEMS

    CERN Document Server

    Satyanarayana, N; Lim, Seh

    2013-01-01

    This book brings together recent developments in the areas of MEMS tribology, novel lubricants and coatings for nanotechnological applications, biomimetics in tribology and fundamentals of micro/nano-tribology. Tribology plays important roles in the functioning and durability of machines at small length scales because of the problems associated with strong surface adhesion, friction, wear etc. Recently, a number of studies have been conducted to understand tribological phenomena at nano/micro scales and many new tribological solutions for MEMS have been proposed.

  17. Nano structural anodes for radiation detectors

    Science.gov (United States)

    Cordaro, Joseph V.; Serkiz, Steven M.; McWhorter, Christopher S.; Sexton, Lindsay T.; Retterer, Scott T.

    2015-07-07

    Anodes for proportional radiation counters and a process of making the anodes is provided. The nano-sized anodes when present within an anode array provide: significantly higher detection efficiencies due to the inherently higher electric field, are amenable to miniaturization, have low power requirements, and exhibit a small electromagnetic field signal. The nano-sized anodes with the incorporation of neutron absorbing elements (e.g., .sup.10B) allow the use of neutron detectors that do not use .sup.3He.

  18. The nano-materials, at the heart of the nano galaxy; Les nano-materiaux, au coeur de la galaxie nano

    Energy Technology Data Exchange (ETDEWEB)

    Le Marois, G. [Direction Generale de l' Industrie, des Technologies de l' Information et des Postes, 75 - Paris (France); Carlac, D. [Societe Developpement et Conseil, 51 - Reims (France)

    2004-02-01

    The researches on nano-materials are continuously increasing in most of industrialized countries. Between 1998 and 2003, the corresponding investment has been multiplied by six in Europe, eight in Usa and in Japan, to reach 3 milliards of euros in the world. Based on the nano-technologies development, these materials would represent the main part of the market at short and middle dated. Many examples of utilization are presented. (A.L.B.)

  19. Brain imaging

    International Nuclear Information System (INIS)

    Mishkin, F.S.

    1978-01-01

    The techniques of brain imaging and results in perfusion studies and delayed images are outlined. An analysis of the advantages and disadvantages of the brain scan in a variety of common problems is discussed, especially as compared with other available procedures. Both nonneoplastic and neoplastic lesions are considered. (Auth/C.F.)

  20. Synthesis, optical properties and growth mechanism of MnO nano structures

    Science.gov (United States)

    Pandey, B. K.; Shahi, A. K.; Gopal, R.

    2013-10-01

    Manganese oxide (MnO) colloidal nanoparticles have been successfully synthesized by pulse laser ablation in double distilled water. Nd: YAG laser with focused output operating at different pulse energies (20, 30, 40, 50 mJ/pulse) was used for ablation. Synthesized MnO nano crystal phase and structure were confirmed by X-ray diffraction and SAED pattern. Optical properties of as synthesized MnO nano colloidal solution were studied by UV-vis absorption spectroscopy. Optical particle size and band gap of as synthesized MnO colloidal nanoparticles were calculated. Particle shape and size were determined by TEM/SEM image. It is observed that MnO nano colloidal particles assembled to make different structures after aging in the liquid media. Aspect ratio has been calculated from SEM picture. MnO nanoparticles show weak antiferromagnetic behavior at room temperature as measured by VSM. A typical mechanism has been proposed for the formation of different nanostructures.

  1. Magnetically-refreshable receptor platform structures for reusable nano-biosensor chips

    International Nuclear Information System (INIS)

    Yoo, Haneul; Cho, Dong-guk; Park, Juhun; Nam, Ki Wan; Cho, Young Tak; Chen, Xing; Hong, Seunghun; Lee, Dong Jun; Park, Jae Yeol

    2016-01-01

    We developed a magnetically-refreshable receptor platform structure which can be integrated with quite versatile nano-biosensor structures to build reusable nano-biosensor chips. This structure allows one to easily remove used receptor molecules from a biosensor surface and reuse the biosensor for repeated sensing operations. Using this structure, we demonstrated reusable immunofluorescence biosensors. Significantly, since our method allows one to place receptor molecules very close to a nano-biosensor surface, it can be utilized to build reusable carbon nanotube transistor-based biosensors which require receptor molecules within a Debye length from the sensor surface. Furthermore, we also show that a single sensor chip can be utilized to detect two different target molecules simply by replacing receptor molecules using our method. Since this method does not rely on any chemical reaction to refresh sensor chips, it can be utilized for versatile biosensor structures and virtually-general receptor molecular species. (paper)

  2. Tungsten nano-tendril growth in the Alcator C-Mod divertor

    International Nuclear Information System (INIS)

    Wright, G.M.; Brunner, D.; Labombard, B.; Lipschultz, B.; Terry, J.L.; Whyte, D.G.; Baldwin, M.J.; Doerner, R.P.

    2012-01-01

    Growth of tungsten nano-tendrils (‘fuzz’) has been observed for the first time in the divertor region of a high-power density tokamak experiment. After 14 consecutive helium L-mode discharges in Alcator C-Mod, the tip of a tungsten Langmuir probe at the outer strike point was fully covered with a layer of nano-tendrils. The thickness of the individual nano-tendrils (50–100 nm) and the depth of the layer (600 ± 150 nm) are consistent with observations from experiments on linear plasma devices. The observation of tungsten fuzz in a tokamak may have important implications for material erosion, dust formation, divertor lifetime and tokamak operations in next-step devices. (letter)

  3. Alternative chemical-based synthesis routes and characterization of nano-scale particles

    International Nuclear Information System (INIS)

    Brocchi, E.A.; Motta, M.S.; Solorzano, I.G.; Jena, P.K.; Moura, F.J.

    2004-01-01

    Different nano-scale particles have been synthesized by alternative routes: nitrates dehydratation and oxide, or co-formed oxides, reduction by hydrogen. Chemical-based synthesis routes are described and thermodynamics studies and kinetics data are presented to support the feasibility for obtaining single-phase oxides and co-formed two-phase oxides. In addition, the reduction reaction has been applied to successfully produce metal/ceramic nanocomposites. Structural characterization has been carried out by means of X-ray diffraction and, more extensively, transmission electron microscopy operating in conventional diffraction contrast mode (CTEM) and high-resolution mode (HRTEM). Nano-scale size distribution of oxide particles is well demonstrated together with their defect-free structure in the lower range, around 20 nm, size. Structural features related to the synthesized nano-composites are also presented

  4. Oxide nano crystals for in vivo imaging

    International Nuclear Information System (INIS)

    Heinrich, E.

    2005-01-01

    For small animal, fluorescence imaging is complementary with other techniques such as nuclear imaging (PET, SPECT). In vivo imaging studies imply the development of new luminescent probes, with a better sensitivity and a better biological targeting. These markers must filled biological and optical conditions. Our goal is to study new doped lanthanides oxide nano-crystals, their properties, their functionalization and their ability to target biological molecules. Characterizations of Y 2 O 3 :Eu and Y 2 SiO 5 :Eu nano-crystals (light diffusion, spectrometry, microscopy) allowed the determination of their size, their fluorescence properties but also their photo-bleaching. Means of stabilization of the nanoparticles were also studied in order to decrease their aggregation. Gd 2 O 3 :Eu nano-crystals were as well excited by X rays. Nano-crystals of Y 2 SiO 5 :Eu were functionalized, and organic ligands grafting evidenced by fluorescence and NMR. The functionalized nano-crystals could then recognized biological targets (streptavidin-biotin) and be incubated in the presence of HeLa cells. This report deals with the properties of these nano-crystals and their ability to meet the optical and biological conditions required for the application of in vivo imaging. (author)

  5. Development of nano SiO2 incorporated nano zinc phosphate coatings on mild steel

    International Nuclear Information System (INIS)

    Tamilselvi, M.; Kamaraj, P.; Arthanareeswari, M.; Devikala, S.; Selvi, J. Arockia

    2015-01-01

    Highlights: • Nano SiO 2 incorporated nano zinc phosphate coating on mild steel was developed. • Coatings showed enhanced corrosion resistance. • The nano SiO 2 is adsorbed on mild steel surface and become nucleation sites. • The nano SiO 2 accelerates the phosphating process. - Abstract: This paper reports the development of nano SiO 2 incorporated nano zinc phosphate coatings on mild steel at low temperature for achieving better corrosion protection. A new formulation of phosphating bath at low temperature with nano SiO 2 was attempted to explore the possibilities of development of nano zinc phosphate coatings on mild steel with improved corrosion resistance. The coatings developed were studied by Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDX), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Electrochemical measurements. Significant variation in the coating weight, morphology and corrosion resistance was observed as nano SiO 2 concentrations varied from 0.5–4 g/L. The results showed that, the nano SiO 2 in the phosphating solution changed the initial potential of the interface between mild steel substrate and phosphating solution and reduce the activation energy of the phosphating process, increase the nucleation sites and yielded zinc phosphate coatings of higher coating weight, greater surface coverage and enhanced corrosion resistance. Better corrosion resistance was observed for coatings derived from phosphating bath containing 1.5 g/L nano SiO 2 . The new formulation reported in the present study was free from Ni or Mn salts and had very low concentration of sodium nitrite (0.4 g/L) as accelerator

  6. Transparent electrode designs based on optimal nano-patterning of metallic films

    KAUST Repository

    Catrysse, Peter B.

    2010-09-10

    Transparent conductive electrodes are critical to the operation of optoelectronic devices, such as photovoltaic cells and light emitting diodes. Effective electrodes need to combine excellent electrical and optical properties. Metal oxides, such as indium tin oxide, are commonly used. There is substantial interest in replacing them, however, motivated by practical problems and recent discoveries regarding the optics of nano-patterned metals. When designing nano-patterned metallic films for use as electrodes, one needs to account for both optical and electrical properties. In general, it is insufficient to optimize nano-structured films based upon optical properties alone, since structural variations will also affect the electrical properties. In this work, we investigate the need for simultaneous optical and electrical performance by analyzing the optical properties of a class of nano-patterned metallic electrodes that is obtained by a constant-sheet-resistance transformation. Within such a class the electrical and optical properties can be separated, i.e., the sheet resistance can be kept constant and the transmittance can be optimized independently. For simple one-dimensional periodic patterns with constant sheet-resistance, we find a transmission maximum (polarization-averaged) when the metal sections are narrow (< 40 nm, ~ 10% metal fill-factor) and tall (> 100 nm). Our design carries over to more complex two-dimensional (2D) patterns. This is significant as there are no previous reports regarding numerical studies on the optical and electrical properties of 2D nano-patterns in the context of electrode design.

  7. X-ray lithography for micro- and nano-fabrication at ELETTRA for interdisciplinary applications

    International Nuclear Information System (INIS)

    Di Fabrizio, E; Fillipo, R; Cabrini, S

    2004-01-01

    ELETTRA (http://www.elettra.trieste.it/index.html) is a third generation synchrotron radiation source facility operating at Trieste, Italy, and hosts a wide range of research activities in advanced materials analysis and processing, biology and nano-science at several various beam lines. The energy spectrum of ELETTRA allows x-ray nano-lithography using soft (1.5 keV) and hard x-ray (10 keV) wavelengths. The Laboratory for Interdisciplinary Lithography (LIILIT) was established in 1998 as part of an Italian national initiative on micro- and nano-technology project of INFM and is funded and supported by the Italian National Research Council (CNR), INFM and ELETTRA. LILIT had developed two dedicated lithographic beam lines for soft (1.5 keV) and hard x-ray (10 keV) for micro- and nano-fabrication activities for their applications in engineering, science and bio-medical applications. In this paper, we present a summary of our research activities in micro- and nano-fabrication involving x-ray nanolithography at LILIT's soft and hard x-ray beam lines

  8. In-situ TEM observation of nano-void formation in UO2 under irradiation

    Science.gov (United States)

    Sabathier, C.; Martin, G.; Michel, A.; Carlot, G.; Maillard, S.; Bachelet, C.; Fortuna, F.; Kaitasov, O.; Oliviero, E.; Garcia, P.

    2014-05-01

    Transmission electron microscopy (TEM) observations of UO2 polycrystals irradiated in situ with 4 MeV Au ions were performed at room temperature (RT) to better understand the mechanisms of cavity and ultimately fission products nucleation in UO2. Experiments were carried out at the JANNuS Orsay facility that enables in situ ion irradiations inside the microscope to be carried out. The majority of 4 MeV gold ions were transmitted through the thin foil, and the induced radiation defects were investigated by TEM. Observations showed that nano-void formation occurs at ambient temperature in UO2 thin foils irradiated with energetic heavy ions under an essentially nuclear energy loss regime. The diameter and density of nano-objects were measured as a function of the gold irradiation dose at RT. A previous paper has also revealed a similar nano-object population after a Xe implantation performed at 390 keV at 870 K. The nano-object density was modelled using simple concepts derived from Classical Molecular Dynamics simulations. The results are in good agreement, which suggests a mechanism of heterogeneous nucleation induced by energetic cascade overlaps. This indicates that nano-void formation mechanism is controlled by radiation damage. Such nanovoids are likely to act as sinks for mobile fission products during reactor operation.

  9. Nonlinear super-resolution nano-optics and applications

    CERN Document Server

    Wei, Jingsong

    2015-01-01

    This book covers many advances in the subjects of nano-optics and nano photonics. The author describes the principle and technical schematics of common methods for breaking through the optical diffraction limit and focuses on realizing optical super-resolution with nonlinear effects of thin film materials. The applications of nonlinear optical super-resolution effects in nano-data storage, nanolithography, and nano-imaging are also presented. This book is useful to graduate students majoring in optics and nano science and also serves as a reference book for academic researchers, engineers, technical professionals in the fields of super-resolution optics and laser techniques, nano-optics and nano photonics, nano-data storage, nano imaging, micro/nanofabrication and nanolithography and nonlinear optics.

  10. Nanomanufacturing : nano-structured materials made layer-by-layer.

    Energy Technology Data Exchange (ETDEWEB)

    Cox, James V.; Cheng, Shengfeng; Grest, Gary Stephen; Tjiptowidjojo, Kristianto (University of New Mexico); Reedy, Earl David, Jr.; Fan, Hongyou; Schunk, Peter Randall; Chandross, Michael Evan; Roberts, Scott A.

    2011-10-01

    Large-scale, high-throughput production of nano-structured materials (i.e. nanomanufacturing) is a strategic area in manufacturing, with markets projected to exceed $1T by 2015. Nanomanufacturing is still in its infancy; process/product developments are costly and only touch on potential opportunities enabled by growing nanoscience discoveries. The greatest promise for high-volume manufacturing lies in age-old coating and imprinting operations. For materials with tailored nm-scale structure, imprinting/embossing must be achieved at high speeds (roll-to-roll) and/or over large areas (batch operation) with feature sizes less than 100 nm. Dispersion coatings with nanoparticles can also tailor structure through self- or directed-assembly. Layering films structured with these processes have tremendous potential for efficient manufacturing of microelectronics, photovoltaics and other topical nano-structured devices. This project is designed to perform the requisite R and D to bring Sandia's technology base in computational mechanics to bear on this scale-up problem. Project focus is enforced by addressing a promising imprinting process currently being commercialized.

  11. Pluggable Controllers and Nano-Patterns in Java with Lola

    Directory of Open Access Journals (Sweden)

    Yossi Gil

    2017-09-01

    Full Text Available Pluggable controllers are a different way to design control constructors such as if, while, do, switch, and operators such as short circuit con-junction (&& and the “?.” operator of the Swift programming language. Adoption of pluggable controllers enables the final user to modify and extend the control flow constructs (if, while, etc. of an underlying programming language, the same way they can do if they implement functions such as printf and class String in a standard library. In modular, pluggable controller based language design, beside core control constructors, there are others, defined in standard libraries, with the purpose of augmenting and enriching the language. These pluggable controllers are extensible and replaceable. Being less intertwined in the main language, control constructor libraries can evolve independently from it, and their releases do not mandate new language releases. We illustrate the implementation of pluggable controllers using Lola, a powerful language-independent preprocessor and macro language. We demonstrate the introduction of new pluggable controllers with two case studies. The implementation of a Java stenography based on prevalent Java idioms, called “nano-patterns” or nanos, and the introduction in Java of new code constructs inspired by the Mathematica language’s commands.

  12. Aluminum Templates of Different Sizes with Micro-, Nano- and Micro/Nano-Structures for Cell Culture

    Directory of Open Access Journals (Sweden)

    Ming-Liang Yen

    2017-10-01

    Full Text Available This study investigates the results of cell cultures on aluminum (Al templates with flat-structures, micro-structures, nano-structures and micro/nano-structures. An Al template with flat-structure was obtained by electrolytic polishing; an Al template with micro-structure was obtained by micro-powder blasting; an Al template with nano-structure was obtained by aluminum anodization; and an Al template with micro/nano-structure was obtained by micro-powder blasting and then anodization. Osteoblast-like cells were cultured on aluminum templates with various structures. The microculture tetrazolium test assay was utilized to assess the adhesion, elongation, and proliferation behaviors of cultured osteoblast-like cells on aluminum templates with flat-structures, micro-structures, nano-structures, and micro/nano-structures. The results showed that the surface characterization of micro/nano-structure of aluminum templates had superhydrophilic property, and these also revealed that an aluminum template with micro/nano-structure could provide the most suitable growth situation for cell culture.

  13. Mass production of polymer nano-wires filled with metal nano-particles.

    Science.gov (United States)

    Lomadze, Nino; Kopyshev, Alexey; Bargheer, Matias; Wollgarten, Markus; Santer, Svetlana

    2017-08-17

    Despite the ongoing progress in nanotechnology and its applications, the development of strategies for connecting nano-scale systems to micro- or macroscale elements is hampered by the lack of structural components that have both, nano- and macroscale dimensions. The production of nano-scale wires with macroscale length is one of the most interesting challenges here. There are a lot of strategies to fabricate long nanoscopic stripes made of metals, polymers or ceramics but none is suitable for mass production of ordered and dense arrangements of wires at large numbers. In this paper, we report on a technique for producing arrays of ordered, flexible and free-standing polymer nano-wires filled with different types of nano-particles. The process utilizes the strong response of photosensitive polymer brushes to irradiation with UV-interference patterns, resulting in a substantial mass redistribution of the polymer material along with local rupturing of polymer chains. The chains can wind up in wires of nano-scale thickness and a length of up to several centimeters. When dispersing nano-particles within the film, the final arrangement is similar to a core-shell geometry with mainly nano-particles found in the core region and the polymer forming a dielectric jacket.

  14. Spin-accumulation effect in magnetic nano-bridge

    International Nuclear Information System (INIS)

    Khvalkovskii, A.V.; Zvezdin, A.A.; Zvezdin, K.A.; Pullini, D.; Perlo, P.

    2004-01-01

    Large values of magnetoresistance experimentally observed in magnetic nano-contacts and nano-wires are explained in terms of spin accumulation. The investigation of the spin-accumulation effect in magnetic nano-contacts (Phys. Rev. Lett. 82 (1999) 2923) and nano-bridges (JETP Lett. 75 (10) (2002) 613), which are considered to be very promising for various spintronic applications, is presented. The two-dimensional spin-diffusion problem in a magnetic nano-bridge is solved. Dependences of the specific resistance of the domain wall and of the distribution of non-equilibrium spin density on the nano-bridge geometry and the material parameters are obtained

  15. Stacked dipole line source excitation of active nano-particles

    DEFF Research Database (Denmark)

    Arslanagic, Samel

    This work investigates electromagnetic properties of cylindrical active coated nano-particles excited by a stac- ked electric dipole line source. The nano-particles consist of a silica nano-core, layered by silver, gold, or copper nano-shell. Attention is devoted to the influence of the source...... location and dipole orientation, the gain constant, and the nano-particle material composition on the electromagnetic field distributions and radiated powers. The results are contrasted to those for the magnetic line source illumination of the nano-particles....

  16. A Fabrication Technique for Nano-gap Electrodes by Atomic Force Microscopy Nano lithography

    International Nuclear Information System (INIS)

    Jalal Rouhi; Shahrom Mahmud; Hutagalung, S.D.; Kakooei, S.

    2011-01-01

    A simple technique is introduced for fabrication of nano-gap electrodes by using nano-oxidation atomic force microscopy (AFM) lithography with a Cr/ Pt coated silicon tip. AFM local anodic oxidation was performed on silicon-on-insulator (SOI) surfaces by optimization of desired conditions to control process in contact mode. Silicon electrodes with gaps of sub 31 nm were fabricated by nano-oxidation method. This technique which is simple, controllable, inexpensive and fast is capable of fabricating nano-gap structures. The current-voltage measurements (I-V) of the electrodes demonstrated very good insulating characteristics. The results show that silicon electrodes have a great potential for fabrication of single molecule transistors (SMT), single electron transistors (SET) and the other nano electronic devices. (author)

  17. Applications and Nano toxicity of Carbon Nano tubes and Graphene in Biomedicine Caitlin Fisher

    International Nuclear Information System (INIS)

    Rider, A.E.; Han, Z.J.; Kumar, S.; Levchenko, L.; Ostrikov, K.K.

    2012-01-01

    Owing to their unique mechanical, electrical, optical, and thermal properties, carbon nano structures including carbon nano tubes and graphenes show great promise for advancing the fields of biology and medicine. Many reports have demonstrated the promise of these carbon nano structures and their hybrid structures (composites with polymers, ceramics, and metal nanoparticles, etc.) for a variety of biomedical areas ranging from bio sensing, drug delivery, and diagnostics, to cancer treatment, tissue engineering, and bio terrorism prevention. However, the issue of the safety and toxicity of these carbon nano structures, which is vital to their use as diagnostic and therapeutic tools in biomedical fields, has not been completely resolved. This paper aims to provide a summary of the features of carbon nano tube and graphene-based materials and current research progress in biomedical applications. We also highlight the current opinions within the scientific community on the toxicity and safety of these carbon structures

  18. Adaptive neuro-fuzzy inference system (ANFIS) to predict CI engine parameters fueled with nano-particles additive to diesel fuel

    Science.gov (United States)

    Ghanbari, M.; Najafi, G.; Ghobadian, B.; Mamat, R.; Noor, M. M.; Moosavian, A.

    2015-12-01

    This paper studies the use of adaptive neuro-fuzzy inference system (ANFIS) to predict the performance parameters and exhaust emissions of a diesel engine operating on nanodiesel blended fuels. In order to predict the engine parameters, the whole experimental data were randomly divided into training and testing data. For ANFIS modelling, Gaussian curve membership function (gaussmf) and 200 training epochs (iteration) were found to be optimum choices for training process. The results demonstrate that ANFIS is capable of predicting the diesel engine performance and emissions. In the experimental step, Carbon nano tubes (CNT) (40, 80 and 120 ppm) and nano silver particles (40, 80 and 120 ppm) with nanostructure were prepared and added as additive to the diesel fuel. Six cylinders, four-stroke diesel engine was fuelled with these new blended fuels and operated at different engine speeds. Experimental test results indicated the fact that adding nano particles to diesel fuel, increased diesel engine power and torque output. For nano-diesel it was found that the brake specific fuel consumption (bsfc) was decreased compared to the net diesel fuel. The results proved that with increase of nano particles concentrations (from 40 ppm to 120 ppm) in diesel fuel, CO2 emission increased. CO emission in diesel fuel with nano-particles was lower significantly compared to pure diesel fuel. UHC emission with silver nano-diesel blended fuel decreased while with fuels that contains CNT nano particles increased. The trend of NOx emission was inverse compared to the UHC emission. With adding nano particles to the blended fuels, NOx increased compared to the net diesel fuel. The tests revealed that silver & CNT nano particles can be used as additive in diesel fuel to improve combustion of the fuel and reduce the exhaust emissions significantly.

  19. Superconducting nano-striplines as quantum detectors

    International Nuclear Information System (INIS)

    Casaburi, A.; Ejrnaes, M.; Mattioli, F.; Gaggero, A.; Leoni, R.; Martucciello, N.; Pagano, S.; Ohkubo, M.; Cristiano, R.

    2011-01-01

    The recent progress in the nanofabrication of superconducting films opens the road toward detectors with highly improved performances. This is the case for superconducting nano-striplines where the thickness and the width are pushed down to the extreme limits to realize detectors with unprecedented sensitivity and ultra fast response time. In this way quantum detectors for single photons at telecommunication wavelengths and for macromolecules such as proteins can be realized. As is often the case in applied nanotechnology, it is a challenge to make devices with the necessary macroscopic dimensions that are needed to interface present technologies, while maintaining the performance improvements. For nano-stripline detectors, both the fast temporal response and the device sensitivity is generally degraded when the area is increased. Here, we present how such detectors can be scaled up to macroscopic dimensions without losing the performance of the nano-structured active elements by using an innovative configuration. In order to realize ultrathin superconducting film the nano-layer is growth with a careful setup of the deposition technique which guarantees high quality and thickness uniformity at the nano-scale size. The active nano-strips are defined with the state-of-the-art electron beam nanolithography to achieve a highly uniform linewidth. We present working detectors based on nano-strips with thicknesses 9–40 nm and widths of 100–1000 nm which exhibit unprecedented speed and area coverage (40 × 40 μm 2 for single photon detectors and 1 × 1 mm 2 for single molecule detectors) based on niobium nitride thus enabling practical use of this nanotechnology.

  20. Oxidation of nano-reinforced polyolefins

    International Nuclear Information System (INIS)

    Gutierrez Castro, G.G.

    2010-11-01

    Nano-composite materials attract search due to their improvements on barrier properties by incorporating low level of nano-filler of 5%w. Nowadays, organically modified montmorillonite (MMT-O) is the most used filler due to its high aspect ratio which permits stronger clay/polymer interactions. If nano-reinforced materials are highly performing, the ways in which clay presence affects polyolefin durability have not being subject of a rigorous study, thus they are not yet clear. Our goal was to examine unstabilized clay polypropylene and unstabilized clay polyethylene nano composites to get a better comprehension of the clay effects on their thermo-oxidation process under low temperatures. The effects induced by a dual physic-chemical nature of the clay were explored. The problem was tackled from both experimental and theoretical point of views for degradation process not controlled and controlled by oxygen diffusion (homogenous and heterogeneous respectively). It seems that MMT-O speeds up oxidation. This phenomenon was modeled by adding a catalytic reaction between metallic particles initially present in the MMT-O and hydroperoxide groups (main responsible of oxidation). Regarding the oxygen permeability two situations were confronted: for the clay polypropylene system a decrease of 45% of oxygen permeability was measured. On the other hand, no variation was found for the polyethylene case. This effect was attributed to the fact that polyethylene nano-composite reached a blend morphology less developed than those of the polypropylene nano-composite. Kinetics and oxidation products profiles across the sample thickness were simulated for both systems by coupling oxidation reactions with oxygen diffusion equations. For the polyethylene case, the effects induced by oxidation on molar mass and crystalline morphology were also simulated. Finally, based on a structure-property relationship, simulations of mechanic modulus profiles were performed for the heterogeneous

  1. Polymer/Layered Silicate Nano composites

    International Nuclear Information System (INIS)

    Bakhit, M.E.E.H.

    2012-01-01

    Polymer–clay nano composites have attracted the attention of many researchers and experimental results are presented in a large number of recent papers and patents because of the outstanding mechanical properties and low gas permeabilities that are achieved in many cases. Polymer-clay nano composites are a new class of mineral-field polymer that contain relatively small amounts (<10%) of nanometer-sized clay particles. Polymer/clay nano composites have their origin in the pioneering research conducted at Toyota Central Research Laboratories and the first historical record goes back to 1987. The matrix was nylon-6 and the filler MMT. Because of its many advantages such as high mechanical properties, good gas barrier, flame retardation, etc. polymer/clay nano composites have been intensely investigated and is currently the subject of many research programs. Nano composite materials are commercially important and several types of products with different shapes and applications including food packaging films and containers, engine parts, dental materials, etc. are now available in markets. A number of synthesis routes have been developed in the recent years to prepare these materials, which include intercalation of polymers or prepolymers from solution, in-situ polymerization, melt intercalation etc. In this study, new nano composite materials were produced from the components of rubber (Nbr, SBR and EPDM) as the polymeric matrix and organically modified quaternary alkylammonium montmorillonite in different contents (3, 5, 7, and 10 phr) as the filler by using an extruder then, the rubber nano composite sheets were irradiated at a dose of 0, 50, 75, 100 and 150 KGy using Electron beam Irradiation technique as a crosslinking agent. These new materials can be characterized by using various analytical techniques including X-ray diffractometer XRD, Thermogravimetric analyzer TGA, scanning electron microscope (SEM), transmission electron microscope (TEM),Fourier transform

  2. Neuroprotective and neurorescue effects of a novel polymeric nanoparticle formulation of curcumin (NanoCurc™) in the neuronal cell culture and animal model: implications for Alzheimer's disease.

    Science.gov (United States)

    Ray, Balmiki; Bisht, Savita; Maitra, Amarnath; Maitra, Anirban; Lahiri, Debomoy K

    2011-01-01

    Alzheimer's disease (AD) is characterized by deposition of amyloid-β (Aβ) plaques within the brain parenchyma followed by synaptic loss and neuronal death. Deposited Aβ reacts with activated microglia to produce reactive oxygen species (ROS) and cytochemokines, which lead to severe neuroinflammation. Curcumin is a yellow polyphenol compound found in turmeric, a widely used culinary ingredient that possesses anti-inflammatory and anti-cancer properties and may show efficacy as a potential therapeutic agent in several neuro-inflammatory diseases including AD. However, poor aqueous solubility and sub-optimal systemic absorption from the gastrointestinal tract may represent factors contributing to its failure in clinical trials. To increase curcumin's bioavailability, a polymeric nanoparticle encapsulated curcumin (NanoCurc™) was formulated which is completely water soluble. NanoCurc™ treatment protects neuronally differentiated human SK-N-SH cells from ROS (H2O2) mediated insults. NanoCurc™ also rescues differentiated human SK-N-SH cells, which were previously insulted with H2O2. In vivo, intraperitoneal (IP) NanoCurc™ injection at a dose of 25mg/kg twice daily in athymic mice resulted in significant curcumin levels in the brain (0.32 μg/g). Biochemical study of NanoCurc™-treated athymic mice revealed decreased levels of H2O2 as well as caspase 3 and caspase 7 activities in the brain, accompanied by increased glutathione (GSH) concentrations. Increased free to oxidized glutathione (GSH:GSSH) ratio in athymic mice brain versus controls also indicated a favorable redox intracellular environment. Taken together, these results suggest that NanoCurc™ represents an optimized formulation worthy of assessing the therapeutic value of curcumin in AD.

  3. High-rate nano-crystalline Li{sub 4}Ti{sub 5}O{sub 12} attached on carbon nano-fibers for hybrid supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Naoi, Katsuhiko; Isobe, Yusaku; Aoyagi, Shintaro [Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8558 (Japan); Ishimoto, Shuichi [Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8558 (Japan); Nippon Chemi-Con Corporation, 363 Arakawa, Takahagi-shi, Ibaraki 318-8505 (Japan)

    2010-09-15

    A lithium titanate (Li{sub 4}Ti{sub 5}O{sub 12})-based electrode which can operate at unusually high current density (300 C) was developed as negative electrode for hybrid capacitors. The high-rate Li{sub 4}Ti{sub 5}O{sub 12} electrode has a unique nano-structure consisting of unusually small nano-crystalline Li{sub 4}Ti{sub 5}O{sub 12} (ca. 5-20 nm) grafted onto carbon nano-fiber anchors (nc-Li{sub 4}Ti{sub 5}O{sub 12}/CNF). This nano-structured nc-Li{sub 4}Ti{sub 5}O{sub 12}/CNF composite are prepared by simple sol-gel method under ultra-centrifugal force (65,000 N) followed by instantaneous annealing at 900 C for 3 min. A model hybrid capacitor cell consisting of a negative nc-Li{sub 4}Ti{sub 5}O{sub 12}/CNF composite electrode and a positive activated carbon electrode showed high energy density of 40 Wh L{sup -1} and high power density of 7.5 kW L{sup -1} comparable to conventional EDLCs. (author)

  4. Brain tumor - primary - adults

    Science.gov (United States)

    ... Vestibular schwannoma (acoustic neuroma) - adults; Meningioma - adults; Cancer - brain tumor (adults) ... Primary brain tumors include any tumor that starts in the brain. Primary brain tumors can start from brain cells, ...

  5. Brain Stimulation Therapies

    Science.gov (United States)

    ... Magnetic Seizure Therapy Deep Brain Stimulation Additional Resources Brain Stimulation Therapies Overview Brain stimulation therapies can play ... for a shorter recovery time than ECT Deep Brain Stimulation Deep brain stimulation (DBS) was first developed ...

  6. Brain radiation - discharge

    Science.gov (United States)

    Radiation - brain - discharge; Cancer - brain radiation; Lymphoma - brain radiation; Leukemia - brain radiation ... Decadron) while you are getting radiation to the brain. It may make you hungrier, cause leg swelling ...

  7. Brain abscess

    Science.gov (United States)

    ... found. However, the most common source is a lung infection. Less often, a heart infection is the cause. The following raise your chance of developing a brain abscess: A weakened immune system (such as in people ...

  8. Life Cycle Analysis of Dedicated Nano-Launch Technologies

    Science.gov (United States)

    Zapata, Edgar; McCleskey, Carey (Editor); Martin, John; Lepsch, Roger; Ternani, Tosoc

    2014-01-01

    Recent technology advancements have enabled the development of small cheap satellites that can perform useful functions in the space environment. Currently, the only low cost option for getting these payloads into orbit is through ride share programs - small satellites awaiting the launch of a larger satellite, and then riding along on the same launcher. As a result, these small satellite customers await primary payload launches and a backlog exists. An alternative option would be dedicated nano-launch systems built and operated to provide more flexible launch services, higher availability, and affordable prices. The potential customer base that would drive requirements or support a business case includes commercial, academia, civil government and defense. Further, NASA technology investments could enable these alternative game changing options. With this context, in 2013 the Game Changing Development (GCD) program funded a NASA team to investigate the feasibility of dedicated nano-satellite launch systems with a recurring cost of less than $2 million per launch for a 5 kg payload to low Earth orbit. The team products would include potential concepts, technologies and factors for enabling the ambitious cost goal, exploring the nature of the goal itself, and informing the GCD program technology investment decision making process. This paper provides an overview of the life cycle analysis effort that was conducted in 2013 by an inter-center NASA team. This effort included the development of reference nano-launch system concepts, developing analysis processes and models, establishing a basis for cost estimates (development, manufacturing and launch) suitable to the scale of the systems, and especially, understanding the relationship of potential game changing technologies to life cycle costs, as well as other factors, such as flights per year.

  9. Brain imaging and brain function

    International Nuclear Information System (INIS)

    Sokoloff, L.

    1985-01-01

    This book is a survey of the applications of imaging studies of regional cerebral blood flow and metabolism to the investigation of neurological and psychiatric disorders. Contributors review imaging techniques and strategies for measuring regional cerebral blood flow and metabolism, for mapping functional neural systems, and for imaging normal brain functions. They then examine the applications of brain imaging techniques to the study of such neurological and psychiatric disorders as: cerebral ischemia; convulsive disorders; cerebral tumors; Huntington's disease; Alzheimer's disease; depression and other mood disorders. A state-of-the-art report on magnetic resonance imaging of the brain and central nervous system rounds out the book's coverage

  10. Effect of high content nano-thoria addition on the properties of tungsten electrode

    International Nuclear Information System (INIS)

    Wang Fazhan; Zhuge Fei; Zhang Hui; Ding Bingjun

    2003-01-01

    By hot swaging, the nano-composite W-4.5%ThO 2 cathode was fabricated. A comparative investigation has been made on the operation characteristics for a conventional W-2%ThO 2 cathode, a conventional W-4%ThO 2 cathode and a nano-composite W-4.5%ThO 2 cathode. The results showed that the arc starting and arc voltage-current characteristic of the nano-composite W-4.5%ThO 2 electrode was the best among the three cathodes. These operating characteristics depended on the content and the size of thoria. The anti-erosion ability of the nano-composite W-4.5%ThO 2 cathode was slightly better than that of conventional W-4%ThO 2 cathode, but was obviously improved as compared to W-2%ThO 2 cathode, indicating that the content of thoria governs the resistance to arc erosion of the electrodes

  11. Nano-plastics in the aquatic environment.

    Science.gov (United States)

    Mattsson, K; Hansson, L-A; Cedervall, T

    2015-10-01

    The amount of plastics released to the environment in modern days has increased substantially since the development of modern plastics in the early 1900s. As a result, concerns have been raised by the public about the impact of plastics on nature and on, specifically, aquatic wildlife. Lately, much attention has been paid to macro- and micro-sized plastics and their impact on aquatic organisms. However, micro-sized plastics degrade subsequently into nano-sizes whereas nano-sized particles may be released directly into nature. Such particles have a different impact on aquatic organisms than larger pieces of plastic due to their small size, high surface curvature, and large surface area. This review describes the possible sources of nano-sized plastic, its distribution and behavior in nature, the impact of nano-sized plastic on the well-being of aquatic organisms, and the difference of impact between nano- and micro-sized particles. We also identify research areas which urgently need more attention and suggest experimental methods to obtain useful data.

  12. Instrument platforms for nano liquid chromatography.

    Science.gov (United States)

    Šesták, Jozef; Moravcová, Dana; Kahle, Vladislav

    2015-11-20

    The history of liquid chromatography started more than a century ago and miniaturization and automation are two leading trends in this field. Nanocolumn liquid chromatography (nano LC) and largely synonymous capillary liquid chromatography (capillary LC) are the most recent results of this process where miniaturization of column dimensions and sorbent particle size play crucial role. Very interesting results achieved in the research of extremely miniaturized LC columns at the end of the last century lacked distinctive raison d'être and only advances in mass spectrometry brought a real breakthrough. Configuration of nano LC-electrospray ionization mass spectrometry (LC-ESI-MS) has become a basic tool in bioanalytical chemistry, especially in proteomics. This review discusses and summarizes past and current trends in the realization of nano liquid chromatography (nano LC) platforms. Special attention is given to the mobile phase delivery under nanoflow rates (isocratic, gradient) and sample injection to the nanocolumn. Available detection techniques applied in nano LC separations are also briefly discussed. We followed up the key themes from the original scientific reports over gradual improvements up to the contemporary commercial solutions. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Nano antibody therapy for cancer

    International Nuclear Information System (INIS)

    Venkatachallam, M.; Sivakumar, T.; Nazeema; Venkateswari, P.

    2011-01-01

    Nanomedicine, an offshoot of nanotechnology, refers to highly specific medical intervention at the molecular scale for curing disease or repairing damaged tissues, such as bone, muscle, or nerve. Nanotechnology can have an early, paradigm-changing impact on how clinicians will detect cancer in its earliest stages. Exquisitely sensitive devices constructed of nanoscale components-such as nanocantilevers, nanowires and nanochannels-offer the potential for detecting even the rarest molecular signals associated with malignancy. One of the most pressing needs in clinical oncology is for imaging agents that can identify tumors that are far smaller than is possible with today's technology, at a scale of 100,000 cells rather than 1,000,000,000 cells. A new approach in nanotechnology for treating cancer incorporates nano iron particles and attaches them to an antibody that has targets only cancer cells and not healthy cells. The treatment works in two steps. This treatment is an ingenious way to make localized tumor ablation a systemic treatment. The advantages are incredible. There are absolutely no side effects from this treatment. It is not painful or even uncomfortable. The iron particles get flushed harmlessly from the body. It is not a drug and so the cancer cannot build up a resistance to the treatment. It is a systematic treatment; even cancer cells and tumors that are not known about get heated up and ablated. This treatment can even be used to enhance imaging of the cancer because once the cancer cells are coated with the iron particles, they are easy to identify. Everything depends on how reliably the antibodies target cancer cells and not healthy cells. When used in conjunction with other systemic treatments, such as vaccine treatments, we could be looking at a time when even advanced cancers can be brought under control. (author)

  14. Structure-­mediated nano-­biophotonics

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Villangca, Mark Jayson; Bañas, Andrew Rafael

    2015-01-01

    The synergy between photonics, nanotechnology and biotechnology is spawning the emerging fields of nano-biotechnology and nano-biophotonics. Photonic innovations already hurdle the diffraction barrier for imaging with nanoscopic resolutions. However, scientific hypothesis testing demands tools...

  15. Nano Surface Engineering in the 21st Century

    Institute of Scientific and Technical Information of China (English)

    Xu Bin-shi; Wang Hai-dou; Dong Shi-yun; Shi Pei-jing; Xu Yi

    2004-01-01

    Nano surface engineering is the new development of surface engineering, and is the typical representation that the advanced nano technology improves the traditional surface engineering. The connotation of nano surface engineering is profound. The initial stage of nano surface engineering is realized at present day. The key technologies of nano surface engineering are the support to the equipment remanufacturing. Today the relatively mature key technologies are: nano thermal spraying technology, nano electric-brush plating technology, nano self-repairing anti-friction technology and metal surface nanocrystallization, etc. Many scientific issues have been continuously discovered. Meanwhile they have been applied in the practice more and more, and have archived the excellent remanufacturing effect.

  16. Assessing nano cellulose developments using science and technology indicators

    International Nuclear Information System (INIS)

    Milanez, Douglas Henrique; Amaral, Roniberto Morato do; Faria, Leandro Innocentini Lopes de; Gregolin, Jose Angelo Rodrigues

    2013-01-01

    This research aims to examine scientific and technological trends of developments in nano cellulose based on scientometric and patent indicators obtained from the Science Citation Index and Derwent Innovations Index in 2001-2010. The overall nano cellulose activity indicators were compared to nanotechnology and other selected nano materials. Scientific and technological future developments in nano cellulose were forecasted using extrapolation growth curves and the main countries were also mapped. The results showed that nano cellulose publications and patent documents have increased rapidly over the last five years with an average growth rate higher than that of nanotechnology and fullerene. The USA, Japan, France, Sweden and Finland all played a significant role in nano cellulose development and the extrapolation growth curves suggested that nano cellulose scientific and technological activities are still emerging. Finally, the evidence from this study recommends monitoring nano cellulose S and T advances in the coming years. (author)

  17. Assessing nano cellulose developments using science and technology indicators

    Energy Technology Data Exchange (ETDEWEB)

    Milanez, Douglas Henrique; Amaral, Roniberto Morato do; Faria, Leandro Innocentini Lopes de; Gregolin, Jose Angelo Rodrigues, E-mail: douglasmilanez@yahoo.com.br [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Nucleo de Informacao Tecnologica em Materiais. Dept. de Engenharia de Materiais

    2013-11-01

    This research aims to examine scientific and technological trends of developments in nano cellulose based on scientometric and patent indicators obtained from the Science Citation Index and Derwent Innovations Index in 2001-2010. The overall nano cellulose activity indicators were compared to nanotechnology and other selected nano materials. Scientific and technological future developments in nano cellulose were forecasted using extrapolation growth curves and the main countries were also mapped. The results showed that nano cellulose publications and patent documents have increased rapidly over the last five years with an average growth rate higher than that of nanotechnology and fullerene. The USA, Japan, France, Sweden and Finland all played a significant role in nano cellulose development and the extrapolation growth curves suggested that nano cellulose scientific and technological activities are still emerging. Finally, the evidence from this study recommends monitoring nano cellulose S and T advances in the coming years. (author)

  18. Poly(lactic-co-glycolic) acid loaded nano-insulin has greater potentials of combating arsenic induced hyperglycemia in mice: Some novel findings

    Energy Technology Data Exchange (ETDEWEB)

    Samadder, Asmita; Das, Jayeeta; Das, Sreemanti; De, Arnab; Saha, Santu Kumar; Bhattacharyya, Soumya Sundar; Khuda-Bukhsh, Anisur Rahman, E-mail: prof_arkb@yahoo.co.in

    2013-02-15

    Diabetes is a menacing problem, particularly to inhabitants of groundwater arsenic contaminated areas needing new medical approaches. This study examines if PLGA loaded nano-insulin (NIn), administered either intraperitoneally (i.p.) or through oral route, has a greater cost-effective anti-hyperglycemic potential than that of insulin in chronically arsenite-fed hyperglycemic mice. The particle size, morphology and zeta potential of nano-insulin were determined using dynamic light scattering method, scanning electronic and atomic force microscopies. The ability of the nano-insulin (NIn) to cross the blood–brain barrier (BBB) was also checked. Circular dichroic spectroscopic (CD) data of insulin and nano-insulin in presence or absence of arsenic were compared. Several diabetic markers in different groups of experimental and control mice were assessed. The mitochondrial functioning through indices like cytochrome c, pyruvate-kinase, glucokinase, ATP/ADP ratio, mitochondrial membrane potential, cell membrane potential and calcium-ion level was also evaluated. Expressions of the relevant marker proteins and mRNAs like insulin, GLUT2, GLUT4, IRS1, IRS2, UCP2, PI3, PPARγ, CYP1A1, Bcl2, caspase3 and p38 for tracking-down the signaling cascade were also analyzed. Results revealed that i.p.-injected nano-encapsulated-insulin showed better results; NIn, due to its smaller size, faster mobility, site-specific release, could cross BBB and showed positive modulation in mitochondrial signaling cascades and other downstream signaling molecules in reducing arsenic-induced-hyperglycemia. CD data indicated that nano-insulin had less distorted secondary structure as compared with that of insulin in presence of arsenic. Thus, overall analyses revealed that PLGA nano-insulin showed better efficacy in combating arsenite-induced-hyperglycemia than that of insulin and therefore, has greater potentials for use in nano-encapsulated form. - Highlights: ► PLGA encapsulated nano

  19. Poly(lactic-co-glycolic) acid loaded nano-insulin has greater potentials of combating arsenic induced hyperglycemia in mice: Some novel findings

    International Nuclear Information System (INIS)

    Samadder, Asmita; Das, Jayeeta; Das, Sreemanti; De, Arnab; Saha, Santu Kumar; Bhattacharyya, Soumya Sundar; Khuda-Bukhsh, Anisur Rahman

    2013-01-01

    Diabetes is a menacing problem, particularly to inhabitants of groundwater arsenic contaminated areas needing new medical approaches. This study examines if PLGA loaded nano-insulin (NIn), administered either intraperitoneally (i.p.) or through oral route, has a greater cost-effective anti-hyperglycemic potential than that of insulin in chronically arsenite-fed hyperglycemic mice. The particle size, morphology and zeta potential of nano-insulin were determined using dynamic light scattering method, scanning electronic and atomic force microscopies. The ability of the nano-insulin (NIn) to cross the blood–brain barrier (BBB) was also checked. Circular dichroic spectroscopic (CD) data of insulin and nano-insulin in presence or absence of arsenic were compared. Several diabetic markers in different groups of experimental and control mice were assessed. The mitochondrial functioning through indices like cytochrome c, pyruvate-kinase, glucokinase, ATP/ADP ratio, mitochondrial membrane potential, cell membrane potential and calcium-ion level was also evaluated. Expressions of the relevant marker proteins and mRNAs like insulin, GLUT2, GLUT4, IRS1, IRS2, UCP2, PI3, PPARγ, CYP1A1, Bcl2, caspase3 and p38 for tracking-down the signaling cascade were also analyzed. Results revealed that i.p.-injected nano-encapsulated-insulin showed better results; NIn, due to its smaller size, faster mobility, site-specific release, could cross BBB and showed positive modulation in mitochondrial signaling cascades and other downstream signaling molecules in reducing arsenic-induced-hyperglycemia. CD data indicated that nano-insulin had less distorted secondary structure as compared with that of insulin in presence of arsenic. Thus, overall analyses revealed that PLGA nano-insulin showed better efficacy in combating arsenite-induced-hyperglycemia than that of insulin and therefore, has greater potentials for use in nano-encapsulated form. - Highlights: ► PLGA encapsulated nano

  20. Formation of Au nano-patterns on various substrates using simplified nano-transfer printing method

    Science.gov (United States)

    Kim, Jong-Woo; Yang, Ki-Yeon; Hong, Sung-Hoon; Lee, Heon

    2008-06-01

    For future device applications, fabrication of the metal nano-patterns on various substrates, such as Si wafer, non-planar glass lens and flexible plastic films become important. Among various nano-patterning technologies, nano-transfer print method is one of the simplest techniques to fabricate metal nano-patterns. In nano-transfer printing process, thin Au layer is deposited on flexible PDMS mold, containing surface protrusion patterns, and the Au layer is transferred from PDMS mold to various substrates due to the difference of bonding strength of Au layer to PDMS mold and to the substrate. For effective transfer of Au layer, self-assembled monolayer, which has strong bonding to Au, is deposited on the substrate as a glue layer. In this study, complicated SAM layer coating process was replaced to simple UV/ozone treatment, which can activates the surface and form the -OH radicals. Using simple UV/ozone treatments on both Au and substrate, Au nano-pattern can be successfully transferred to as large as 6 in. diameter Si wafer, without SAM coating process. High fidelity transfer of Au nano-patterns to non-planar glass lens and flexible PET film was also demonstrated.

  1. Preparation, Characterization, and Modeling of Carbon Nano fiber/Epoxy Nano composites

    International Nuclear Information System (INIS)

    Sun, L.H.; Yang, Z.G.; Ounaies, Z.; Whalen, C.A.; Gao, X.L.

    2011-01-01

    There is a lack of systematic investigations on both mechanical and electrical properties of carbon nano fiber (CNF)-reinforced epoxy matrix nano composites. In this paper, an in-depth study of both static and dynamic mechanical behaviors and electrical properties of CNF/epoxy nano composites with various contents of CNFs is provided. A modified Halpin-Tsai equation is used to evaluate the Young's modulus and storage modulus of the nano composites. The values of Young's modulus predicted using this method account for the effect of the CNF agglomeration and fit well with those obtained experimentally. The results show that the highest tensile strength is found in the epoxy nano composite with a 1.0 wt % CNFs. The alternate-current (AC) electrical properties of the CNF/epoxy nano composites exhibit a typical insulator-conductor transition. The conductivity increases by four orders of magnitude with the addition of 0.1 wt % (0.058 vol %) CNFs and by ten orders of magnitude for nano composites with CNF volume fractions higher than 1.0 wt % (0.578 vol %). The percolation threshold (i.e., the critical CNF volume fraction) is found to be at 0.057 vol %.

  2. Are nano-composites and nano-ionomers suitable for orthodontic bracket bonding?

    Science.gov (United States)

    Uysal, Tancan; Yagci, Ahmet; Uysal, Banu; Akdogan, Gülsen

    2010-02-01

    The aim of this study was to test nano-composite (Filtek Supreme Plus Universal) and a newly introduced nano-ionomer (Ketac N100 Light Curing Nano-Ionomer) restorative to determine their shear bond strength (SBS) and failure site locations in comparison with a conventional light-cure orthodontic bonding adhesive (Transbond XT). Sixty freshly extracted human maxillary premolar teeth were arbitrarily divided into three equal groups. The brackets were bonded to the teeth in each group with different composites, according to the manufacturers' instructions. The SBS values of the brackets were recorded in Megapascals (MPa) using a universal testing machine. Adhesive remnant index scores were determined after failure of the brackets. The data were analysed using analysis of variance, Tukey honestly significant difference, and chi-square tests. The results demonstrated that group 1 (Transbond XT, mean: 12.60 +/- 4.48 MPa) had a higher SBS than that of group 2 (nano-composite, mean: 8.33 +/- 5.16 MPa; P nano-ionomer, mean: 6.14 +/- 2.12 MPa; P Nano-composites and nano-ionomers may be suitable for bonding since they fulfil the previously suggested SBS ranges for clinical acceptability, but they are inferior to a conventional orthodontic composite.

  3. Nano-structural characteristics and optical properties of silver chiral nano-flower sculptured thin films

    International Nuclear Information System (INIS)

    Savaloni, Hadi; Haydari-Nasab, Fatemh; Malmir, Mariam

    2011-01-01

    Silver chiral nano-flowers with 3-, 4- and 5-fold symmetry were produced using oblique angle deposition method in conjunction with the rotation of sample holder with different speeds at different sectors of each revolution corresponding to symmetry order of the acquired nano-flower. Atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM), were employed to obtain morphology and nano-structure of the films. Optical characteristics of silver chiral nano-flower thin films were obtained using single beam spectrophotometer with both s- and p-polarization incident light at 30 o and 70 o incidence angles and at different azimuthal angles (φ). Optical spectra showed both TM (TDM (transverse dipole mode) and TQM (transverse quadruple mode)) and LM (longitudinal mode) Plasmon resonance peaks. For 3- and 4-fold symmetry chiral nano-flowers the s-polarization extinction spectra obtained at different azimuthal angles did not show significant change in the Plasmon peak position while 5-fold symmetry chiral nano-flower showed a completely different behavior, which may be the result of increased surface anisotropy, so when the φ angle is changed the s-polarization response from the surface can change more significantly than that for lower symmetries. In general, for 3-, 4- and 5-fold symmetry chiral nano-flowers a sharp peak at lower wavelengths ( o incidence angle.

  4. Nano, Queensland and cryo-electron microscopy

    International Nuclear Information System (INIS)

    McDowall, A.W.

    2002-01-01

    Full text: In a recent review the authors, Wolfgang Baumeister and Alasdair Steven wrote, '....there is immense opportunity for Cryo-EM, especially as boosted by merging crystallographic structures of individual subunits into moderate resolution Cryo-EM density maps of whole complexes. Electron tomography has now advanced to the point where it is a realistic goal to glimpse molecular machines operating inside cells....' This statement gives testament to the advances made over the past 25 years by many labs around the world to the area of microscopy referred to as Cryo-EM and related 3-D computing technologies. Australian scientific societies have been eager followers of this progress and heard first hand of the new developments in the field at the 1984 ACEM-8 (2). Since those early days the ACEM and other Australian/NZ societies have sponsored numerous researchers and workshops in the field of Cryo-EM to their conferences, Helin Sabil, Wah Chiu, Ron Milligan, Richard Henderson and Werner Kuhlbrandt to name only a few. These visits have stimulated a desire from Australian/NZ researchers to establish collaborations and access to prominent labs in the USA and Europe, where the means and knowledge to provide Cryo EM and 3D reconstruction technology for studying macromolecular complexes is well established. However, Australia has not been backward in seeking to provide its home research community with access to a base in biological molecular microscopy and electron crystallography technology. Since the last ACEM we have seen the emergence of a number of crucial factors, which will make the establishment of a national research facility in this field an operational reality in early 2003. Well publicized is the development of Australia's newest and perhaps most unique research institute, the institute for Molecular Bioscience (IMB) to open at the University of Queensland (UQ) in 2002. The IMB will be the platform for a new research group in advanced computational 3D

  5. Writing to and reading from a nano-scale crossbar memory based on memristors

    International Nuclear Information System (INIS)

    Vontobel, Pascal O; Robinett, Warren; Kuekes, Philip J; Stewart, Duncan R; Straznicky, Joseph; Stanley Williams, R

    2009-01-01

    We present a design study for a nano-scale crossbar memory system that uses memristors with symmetrical but highly nonlinear current-voltage characteristics as memory elements. The memory is non-volatile since the memristors retain their state when un-powered. In order to address the nano-wires that make up this nano-scale crossbar, we use two coded demultiplexers implemented using mixed-scale crossbars (in which CMOS-wires cross nano-wires and in which the crosspoint junctions have one-time configurable memristors). This memory system does not utilize the kind of devices (diodes or transistors) that are normally used to isolate the memory cell being written to and read from in conventional memories. Instead, special techniques are introduced to perform the writing and the reading operation reliably by taking advantage of the nonlinearity of the type of memristors used. After discussing both writing and reading strategies for our memory system in general, we focus on a 64 x 64 memory array and present simulation results that show the feasibility of these writing and reading procedures. Besides simulating the case where all device parameters assume exactly their nominal value, we also simulate the much more realistic case where the device parameters stray around their nominal value: we observe a degradation in margins, but writing and reading is still feasible. These simulation results are based on a device model for memristors derived from measurements of fabricated devices in nano-scale crossbars using Pt and Ti nano-wires and using oxygen-depleted TiO 2 as the switching material.

  6. NanoXCT: a novel technique to probe the internal architecture of pharmaceutical particles.

    Science.gov (United States)

    Wong, Jennifer; D'Sa, Dexter; Foley, Matthew; Chan, John Gar Yan; Chan, Hak-Kim

    2014-11-01

    To demonstrate the novel application of nano X-ray computed tomography (NanoXCT) for visualizing and quantifying the internal structures of pharmaceutical particles. An Xradia NanoXCT-100, which produces ultra high-resolution and non-destructive imaging that can be reconstructed in three-dimensions (3D), was used to characterize several pharmaceutical particles. Depending on the particle size of the sample, NanoXCT was operated in Zernike Phase Contrast (ZPC) mode using either: 1) large field of view (LFOV), which has a two-dimensional (2D) spatial resolution of 172 nm; or 2) high resolution (HRES) that has a resolution of 43.7 nm. Various pharmaceutical particles with different physicochemical properties were investigated, including raw (2-hydroxypropyl)-beta-cyclodextrin (HβCD), poly (lactic-co-glycolic) acid (PLGA) microparticles, and spray-dried particles that included smooth and nanomatrix bovine serum albumin (BSA), lipid-based carriers, and mannitol. Both raw HβCD and PLGA microparticles had a network of voids, whereas spray-dried smooth BSA and mannitol generally had a single void. Lipid-based carriers and nanomatrix BSA particles resulted in low quality images due to high noise-to-signal ratio. The quantitative capabilities of NanoXCT were also demonstrated where spray-dried mannitol was found to have an average void volume of 0.117 ± 0.247 μm(3) and average void-to-material percentage of 3.5%. The single PLGA particle had values of 1993 μm(3) and 59.3%, respectively. This study reports the first series of non-destructive 3D visualizations of inhalable pharmaceutical particles. Overall, NanoXCT presents a powerful tool to dissect and observe the interior of pharmaceutical particles, including those of a respirable size.

  7. Titanium oxide (TiO2) nanoparticles in induction of apoptosis and inflammatory response in brain

    International Nuclear Information System (INIS)

    Meena, Ramovatar; Kumar, Sumit; Paulraj, R.

    2015-01-01

    The ever increasing applications of engineered nanoparticles in 21st century cause serious concern about its potential health risks on living being. Regulatory health risk assessment of such particles has become mandatory for the safe use of nanomaterials in consumer products and medicines. In order to study the mechanism underlying the effects of nano-TiO 2 (TiO 2 nanoparticles) on the brain, wistar rats were administrated intravenously with various doses of nano-TiO 2 (21 nm) through the caudal vein, once a week for 4 weeks and different parameters such as bioaccumulation of nano-TiO 2 , oxidative stress-mediated response, level of inflammatory markers such as NF-κB (p65), HSP 60, p38, nitric oxide, IFN-γ and TNF-α, and level of neurochemicals in brain as well as DNA damage and expression of apoptosis markers (p53, Bax, Bcl-2, and cyto c) were evaluated. Results show that the concentration of nano-TiO 2 in the brain increased with increasing the doses of nano-TiO 2 . Oxidative stress and injury of the brain occurred as nano-TiO 2 appeared to trigger a cascade of reactions such as inflammation, lipid peroxidation, decreases the activities of antioxidative enzymes and melatonin level, the reduction of glutamic acid, downregulated levels of acetylcholinesterase activities, and the increase in caspase-3 activity (a biomarker of apoptosis), DNA fragmentation, and apoptosis. It may be concluded that nano-TiO 2 induces oxidative stress that leads to activation of inflammatory cytokines and an alteration in the level of neurotransmitters resulted in the induction of mitochondrial-mediated apoptosis

  8. Scaling Laws for NanoFET Sensors

    Science.gov (United States)

    Wei, Qi-Huo; Zhou, Fu-Shan

    2008-03-01

    In this paper, we report our numerical studies of the scaling laws for nanoplate field-effect transistor (FET) sensors by simplifying the nanoplates as random resistor networks. Nanowire/tube FETs are included as the limiting cases where the device width goes small. Computer simulations show that the field effect strength exerted by the binding molecules has significant impact on the scaling behaviors. When the field effect strength is small, nanoFETs have little size and shape dependence. In contrast, when the field-effect strength becomes stronger, there exists a lower detection threshold for charge accumulation FETs and an upper detection threshold for charge depletion FET sensors. At these thresholds, the nanoFET devices undergo a transition between low and large sensitivities. These thresholds may set the detection limits of nanoFET sensors. We propose to eliminate these detection thresholds by employing devices with very short source-drain distance and large width.

  9. Nano-optomechanics with optically levitated nanoparticles

    Science.gov (United States)

    Neukirch, Levi P.; Vamivakas, A. Nick

    2015-01-01

    Nano-optomechanics is a vibrant area of research that continues to push the boundary of quantum science and measurement technology. Recently, it has been realised that the optical forces experienced by polarisable nanoparticles can provide a novel platform for nano-optomechanics with untethered mechanical oscillators. Remarkably, these oscillators are expected to exhibit quality factors approaching ?. The pronounced quality factors are a direct result of the mechanical oscillator being freed from a supporting substrate. This review provides an overview of the basic optical physics underpinning optical trapping and optical levitation experiments, it discusses a number of experimental approaches to optical trapping and finally outlines possible applications of this nano-optomechanics modality in hybrid quantum systems and nanoscale optical metrology.

  10. Replication of micro and nano surface geometries

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Hocken, R.J.; Tosello, Guido

    2011-01-01

    The paper describes the state-of-the-art in replication of surface texture and topography at micro and nano scale. The description includes replication of surfaces in polymers, metals and glass. Three different main technological areas enabled by surface replication processes are presented......: manufacture of net-shape micro/nano surfaces, tooling (i.e. master making), and surface quality control (metrology, inspection). Replication processes and methods as well as the metrology of surfaces to determine the degree of replication are presented and classified. Examples from various application areas...... are given including replication for surface texture measurements, surface roughness standards, manufacture of micro and nano structured functional surfaces, replicated surfaces for optical applications (e.g. optical gratings), and process chains based on combinations of repeated surface replication steps....

  11. Electromagnetics of active coated nano-particles

    DEFF Research Database (Denmark)

    Arslanagic, Samel

    2013-01-01

    This work reviews the fundamental properties of several spherical and cylindrical active coated nano-particles excited by their respective single and/or multiple sources of radiation at optical frequencies. Particular attention is devoted to the influence of the source location and orientation, t......, the optical gain constant and the nano-particle material composition on the electric and magnetic near fields, the power flow density, the radiated power as well as the directivities. Resonant as well as quasi-transparent states will be emphasized in the discussion.......This work reviews the fundamental properties of several spherical and cylindrical active coated nano-particles excited by their respective single and/or multiple sources of radiation at optical frequencies. Particular attention is devoted to the influence of the source location and orientation...

  12. Nano materials Synthesis, Applications, and Toxicity 2012

    International Nuclear Information System (INIS)

    Nadagouda, M.N.; Lytle, D.A.; Speth, Th.F.; Dionysiou, D.D.; Mukhopadhyay, Sh.M.

    2013-01-01

    Nano technology presents new opportunities to create better materials and products. Nano materials find wide applications in catalysis, energy production, medicine, environmental remediation, automotive industry, and other sectors of our society. Nano material-containing products are already available globally and include automotive parts, defense application, drug delivery devices, coatings, computers, clothing, cosmetics, sports equipment, and medical devices. This special issue includes emerging advances in the field, with a special emphasis given to nano material synthesis and applications. There is an increasing interest in identifying magnetically separable catalysts for the degradation of wastewater. In this issue, A. Perumal et al. report an investigation of temperature-dependent magnetic properties and photo catalytic activity of CoFe 2 O 4 -Fe 3 O 4 magnetic nano composites (MNCs) synthesized by hydrothermal processes. These MNCs have saturation magnetization of 90 emu/g and coercivity (HC) of 530 Oe. The photo catalytic activity of the MNCs has been examined on the reduction of methyl orange (MO), a colored compound used in dyeing and printing textiles. The MNCs act as an excellent photo catalyst on the degradation of organic contaminants and degrade 93% of MO in 5 hours of UV irradiation. The photo catalytic activity of MNCs is attributed to remarkably high band gap energy and small particle size. Also, the MNCs with reproducible photo catalytic activity are easily separated from water media by applying an external magnetic field and they act as a promising catalyst for the remediation of textile wastewater. Microwaves can play an important role in orchestrating nano materials for a wide range of technological applications

  13. Mechanism of brain tumor headache.

    Science.gov (United States)

    Taylor, Lynne P

    2014-04-01

    Headaches occur commonly in all patients, including those who have brain tumors. Using the search terms "headache and brain tumors," "intracranial neoplasms and headache," "facial pain and brain tumors," "brain neoplasms/pathology," and "headache/etiology," we reviewed the literature from the past 78 years on the proposed mechanisms of brain tumor headache, beginning with the work of Penfield. Most of what we know about the mechanisms of brain tumor associated headache come from neurosurgical observations from intra-operative dural and blood vessel stimulation as well as intra-operative observations and anecdotal information about resolution of headache symptoms with various tumor-directed therapies. There is an increasing overlap between the primary and secondary headaches and they may actually share a similar biological mechanism. While there can be some criticism that the experimental work with dural and arterial stimulation produced head pain and not actual headache, when considered with the clinical observations about headache type, coupled with improvement after treatment of the primary tumor, we believe that traction on these structures, coupled with increased intracranial pressure, is clearly part of the genesis of brain tumor headache and may also involve peripheral sensitization with neurogenic inflammation as well as a component of central sensitization through trigeminovascular afferents on the meninges and cranial vessels. © 2014 American Headache Society.

  14. Self-aligned periodic Ni nano dots embedded in nano-oxide layer

    International Nuclear Information System (INIS)

    Doi, M.; Izumi, M.; Kawasaki, S.; Miyake, K.; Sahashi, M.

    2007-01-01

    The Ni nano constriction dots embedded in the Ta-nano-oxide layer (NOL) was prepared by the ion beam sputtering (IBS) method. After the various conditions of the oxidations, the structural analyses of the NOL were performed by RHEED, AES and in situ STM/AFM observations. From the current image of the conductive AFM for NOL, the periodically aligned metallic dots with the size around 5-10 nm were successfully observed. The mechanism of the formation of the self-organized aligned Ni nano constriction dots is discussed from the standpoint of the grain size, the crystal orientation, the preferred oxidation of Ta at the diffused interface

  15. Nano-sensing of the orientation of fluorescing molecules with active coated nano-particles

    DEFF Research Database (Denmark)

    Arslanagic, Samel; Ziolkowski, Richard W.

    2015-01-01

    The potential of using active coated nano-particles to determine the orientation of fluorescing molecules is reported. By treating each fluorescing molecule as an electric Hertzian dipole, single and multiple fluorescing molecules emitting coherently and incoherently in various orientations...... are considered in the presence of active coated nano-particles. It is demonstrated that in addition to offering a means to determine the orientation of a single molecule or the over-all orientation of the molecules surrounding it, the nature of the far-field response from the active coated nano...

  16. Long-Term Mechanical Behavior of Nano Silica Sol Grouting

    Directory of Open Access Journals (Sweden)

    Dongjiang Pan

    2018-01-01

    Full Text Available The longevity of grouting has a significant effect on the safe and sustainable operation of many engineering projects. A 500-day experiment was carried out to study the long-term mechanical behavior of nano silica sol grouting. The nano silica sol was activated with different proportions of a NaCl catalyst and cured under fluctuating temperature and humidity conditions. The mechanical parameters of the grout samples were tested using an electrohydraulic uniaxial compression tester and an improved Vicat instrument. Scanning electron microscope, X-ray diffraction, and ultrasonic velocity tests were carried out to analyze the strength change micro-mechanism. Tests showed that as the catalyst dosage in the grout mix is decreased, the curves on the graphs showing changes in the weight and geometric parameters of the samples over time could be divided into three stages, a shrinkage stage, a stable stage, and a second shrinkage stage. The catalyst improved the stability of the samples and reduced moisture loss. Temperature rise was also a driving force for moisture loss. Uniaxial compressive stress-strain curves for all of the samples were elastoplastic. The curves for uniaxial compression strength and secant modulus plotted against time could be divided into three stages. Sample brittleness increased with time and the brittleness index increased with higher catalyst dosages in the latter part of the curing time. Plastic strength-time curves exhibit allometric scaling. Curing conditions mainly affect the compactness, and then affect the strength.

  17. Long-Term Mechanical Behavior of Nano Silica Sol Grouting

    Science.gov (United States)

    Zhang, Nong; Zhang, Chenghao; Qian, Deyu; Han, Changliang; Yang, Sen

    2018-01-01

    The longevity of grouting has a significant effect on the safe and sustainable operation of many engineering projects. A 500-day experiment was carried out to study the long-term mechanical behavior of nano silica sol grouting. The nano silica sol was activated with different proportions of a NaCl catalyst and cured under fluctuating temperature and humidity conditions. The mechanical parameters of the grout samples were tested using an electrohydraulic uniaxial compression tester and an improved Vicat instrument. Scanning electron microscope, X-ray diffraction, and ultrasonic velocity tests were carried out to analyze the strength change micro-mechanism. Tests showed that as the catalyst dosage in the grout mix is decreased, the curves on the graphs showing changes in the weight and geometric parameters of the samples over time could be divided into three stages, a shrinkage stage, a stable stage, and a second shrinkage stage. The catalyst improved the stability of the samples and reduced moisture loss. Temperature rise was also a driving force for moisture loss. Uniaxial compressive stress-strain curves for all of the samples were elastoplastic. The curves for uniaxial compression strength and secant modulus plotted against time could be divided into three stages. Sample brittleness increased with time and the brittleness index increased with higher catalyst dosages in the latter part of the curing time. Plastic strength-time curves exhibit allometric scaling. Curing conditions mainly affect the compactness, and then affect the strength. PMID:29337897

  18. Resonant Spin-Transfer-Torque Nano-Oscillators

    Science.gov (United States)

    Sharma, Abhishek; Tulapurkar, Ashwin A.; Muralidharan, Bhaskaran

    2017-12-01

    Spin-transfer-torque nano-oscillators are potential candidates for replacing the traditional inductor-based voltage-controlled oscillators in modern communication devices. Typical oscillator designs are based on trilayer magnetic tunnel junctions, which have the disadvantages of low power outputs and poor conversion efficiencies. We theoretically propose using resonant spin filtering in pentalayer magnetic tunnel junctions as a possible route to alleviate these issues and present viable device designs geared toward a high microwave output power and an efficient conversion of the dc input power. We attribute these robust qualities to the resulting nontrivial spin-current profiles and the ultrahigh tunnel magnetoresistance, both of which arise from resonant spin filtering. The device designs are based on the nonequilibrium Green's-function spin-transport formalism self-consistently coupled with the stochastic Landau-Lifshitz-Gilbert-Slonczewski equation and Poisson's equation. We demonstrate that the proposed structures facilitate oscillator designs featuring a large enhancement in microwave power of around 1150% and an efficiency enhancement of over 1100% compared to typical trilayer designs. We rationalize the optimum operating regions via an analysis of the dynamic and static device resistances. We also demonstrate the robustness of our structures against device design fluctuations and elastic dephasing. This work sets the stage for pentalyer spin-transfer-torque nano-oscillator device designs that ameliorate major issues associated with typical trilayer designs.

  19. Nb nanoSQUIDs for detection of small spin systems

    Energy Technology Data Exchange (ETDEWEB)

    Woelbing, R.; Nagel, J.; Kemmler, M.; Kleiner, R.; Koelle, D. [Physikalisches Institut, Universitaet Tuebingen (Germany); Kieler, O.; Weimann, T.; Kohlmann, J.; Zorin, A. [Fachbereich 2.4 ' ' Quantenelektronik' ' , PTB Braunschweig (Germany); Buchter, A.; Xue, F.; Poggio, M. [Department of Physics, University of Basel (Switzerland); Rueffer, D.; Russo-Averchi, E.; Fontcuberta i Morral, A. [Laboratoire des Materiaux Semiconducteurs, EPF Lausanne (Switzerland); Huber, R.; Berberich, P. [Physik-Department E10, Technische Universitaet Muenchen (Germany); Grundler, D. [Laboratoire des Materiaux Semiconducteurs, EPF Lausanne (Switzerland); Physik-Department E10, Technische Universitaet Muenchen (Germany)

    2013-07-01

    We report on the realization of highly sensitive dc nanoSQUIDs for the investigation of small spin systems in moderate magnetic fields. The Nb SQUIDs are based on normal metal Josephson junctions made of HfTi and patterned by e-beam lithography. We demonstrate stable operation up to B = ± 50 mT without degradation of rms flux noise (S{sub Φ}{sup 1/2} ≤ 280 nΦ{sub 0}/√(Hz)). We also present a multifunctional system combining a Nb nanoSQUID and a low-temperature magnetic force microscope (LTMFM) with a Ni nanotube as a scanning tip. This system allows for magnetization measurements of the Ni tube by using both, LTMFM and SQUID readout. Furthermore, the measurement of magnetic flux Φ vs. position of the particle provides an experimental determination of the coupling factor φ{sub μ} = Φ/μ between SQUID and Ni tube with magnetic moment μ. The results confirm our predictions from numerical simulations, taking into account the SQUID geometry.

  20. Selective and lithography-independent fabrication of 20 nm nano-gap electrodes and nano-channels for nanoelectrofluidics applications

    International Nuclear Information System (INIS)

    Zhang, J Y; Wang, X F; Wang, X D; Fan, Z C; Li, Y; Ji, An; Yang, F H

    2010-01-01

    A new method has been developed to selectively fabricate nano-gap electrodes and nano-channels by conventional lithography. Based on a sacrificial spacer process, we have successfully obtained sub-100-nm nano-gap electrodes and nano-channels and further reduced the dimensions to 20 nm by shrinking the sacrificial spacer size. Our method shows good selectivity between nano-gap electrodes and nano-channels due to different sacrificial spacer etch conditions. There is no length limit for the nano-gap electrode and the nano-channel. The method reported in this paper also allows for wafer scale fabrication, high throughput, low cost, and good compatibility with modern semiconductor technology.

  1. Rapid fabrication of an ordered nano-dot array by the combination of nano-plastic forming and annealing methods

    International Nuclear Information System (INIS)

    Yoshino, Masahiko; Ohsawa, Hiroki; Yamanaka, Akinori

    2011-01-01

    In this paper, a new fabrication method for an ordered nano-dot array is developed. Combination of coating, nano-plastic forming and annealing processes is studied to produce uniformly sized and ordered gold nano-dot array on a quartz glass substrate. The experimental results reveal that patterning of a groove grid on the gold-coated substrate with NPF is effective to obtain the ordered gold nano-dot array. In the proposed fabrication process, the size of the gold nano-dot can be controlled by adjusting the groove grid size. A minimum gold nano-dot array fabricated on a quartz-glass substrate was 93 nm in diameter and 100 nm in pitch. Furthermore, the mechanism of nano-dot array generation by the presented process is investigated. Using a theoretical model it is revealed that the proposed method is capable of fabrication of smaller nano-dots than 10 nm by controlling process conditions adequately.

  2. Operation Brain Trauma Therapy Extended Studies

    Science.gov (United States)

    2015-05-01

    precluded our ability to move forward. Others agents with favorable voting at our prior drug selection meetings include edaravone and etanercept...Minocycline, P7C3-A20, NACA, NIM-811, Edaravone , and Etanercept, among many others by Dr. Kochanek, with updating of the manual through the most

  3. Brain SPECT

    International Nuclear Information System (INIS)

    Feistel, H.

    1991-01-01

    Brain SPECT investigations have gained broad acceptance since the introduction of the lipophilic tracer Tc-99m-HMPAO. Depending on equipment and objectives in different departments, the examinations can be divided into three groups: 1. Under normal conditions and standardised patient preparation the 'rest' SPECT can be performed in every department with a tomographic camera. In cerebrovascular disease there is a demand for determination of either the perfusion reserve in reversible ischemia or prognostic values in completed stroke. In cases of dementia, SPECT may yield useful results according to differential diagnosis. Central cerebral system involvement in immunologic disease may be estimated with higher sensitivity than in conventional brain imaging procedures. In psychiatric diseases there is only a relative indication for brain SPECT, since results during recent years have been contradictory and may be derived only in interventional manner. In brain tumor diagnostics SPECT with Tl-201 possibly permits grading. In inflammatory disease, especially in viral encephalitis, SPECT may be used to obtain early diagnosis. Normal pressure hydrocephalus can be distinguished from other forms of dementia and, consequently, the necessity for shunting surgery can be recognised. 2. In departments equipped for emergency cases an 'acute' SPECT can be performed in illnesses with rapid changing symptoms such as different forms of migraine, transient global amnesia, epileptic seizures (so-called 'ictal SPECT') or urgent forms like trauma. 3. In cooperation with several departments brain SPECT can be practised as an interventional procedure in clinical and in scientific studies. (orig./MG) [de

  4. X-diffraction technique applied for nano system metrology

    International Nuclear Information System (INIS)

    Kuznetsov, Alexei Yu.; Machado, Rogerio; Robertis, Eveline de; Campos, Andrea P.C.; Archanjo, Braulio S.; Gomes, Lincoln S.; Achete, Carlos A.

    2009-01-01

    The application of nano materials are fast growing in all industrial sectors, with a strong necessity in nano metrology and normalizing in the nano material area. The great potential of the X-ray diffraction technique in this field is illustrated at the example of metals, metal oxides and pharmaceuticals

  5. Security in Nano Communication: Challenges and Open Research Issues

    NARCIS (Netherlands)

    Dressler, Falko; Kargl, Frank

    Nano communication is one of the fastest growing emerging research fields. In recent years, much progress has been achieved in developing nano machines supporting our needs in health care and other scenarios. However, experts agree that only the interaction among nano machines allows to address the

  6. Fabrication of nano piezoelectric based vibration accelerometer for mechanical sensing

    Science.gov (United States)

    Murugan, S.; Prasad, M. V. N.; Jayakumar, K.

    2016-05-01

    An electromechanical sensor unit has been fabricated using nano PZT embedded in PVDF polymer. Such a polymer nano composite has been used as vibration sensor element and sensitivity, detection of mechanical vibration, and linearity measurements have been investigated. It is found from its performance, that this nano composite sensor is suitable for mechanical sensing applications.

  7. Synthesise of Zn O nano wires by direct oxidation method

    International Nuclear Information System (INIS)

    Farbod, M.; Ahangarpour, A.

    2007-01-01

    Zn O is a semiconductor which has a direct and wide energy band which is about 3.37 eV at room temperature. It has various applications from UV lasers, sensitive sensors, solar cells to photo catalysis applications. Zn O has different nano structures such as nanoparticles, nano wires, nano rods, nano tubes and nano belts. The one dimensional Zn O nano structures such as nano wires are very important because of their applications in nano electronics and nano photonics so different methods have been proposed to synthesize them. In this work large scale of Zn O nano wires are produced by direct oxidation a Zn substrate (which was cleaned by chemical methods) in air or oxygen atmosphere at 400 d eg C . Nano wires were investigated by scanning electron microscopy and energy dispersive x-ray measurements. Their diameter is about 30-150 nanometer and their length is about several micrometer. This method which acts without any catalyst is a convenient method to synthesis semiconductor nano wires.

  8. Topology optimization of nano-photonic systems

    DEFF Research Database (Denmark)

    Elesin, Yuriy; Wang, Fengwen; Andkjær, Jacob Anders

    2012-01-01

    We describe recent developments within nano-photonic systems design based on topology optimization. Applications include linear and non-linear optical waveguides, slow-light waveguides, as well as all-dielectric cloaks that minimize scattering or back-scattering from hard obstacles.......We describe recent developments within nano-photonic systems design based on topology optimization. Applications include linear and non-linear optical waveguides, slow-light waveguides, as well as all-dielectric cloaks that minimize scattering or back-scattering from hard obstacles....

  9. Emerging areas of Nano and Smart Materials

    OpenAIRE

    Partha Ghosal

    2016-01-01

    ‘There’s plenty of room at the bottom’ – In 1959, one of the most brilliant physicists the world has ever seen, Richard P. Feynmann, gave us a beautiful introduction to nano-science. Today, after almost seven decades, nano-materials and related technologies are not just a simple extension of regular research and miniaturisation of materials, but have become the prime driver of advancement in science and technology all over the world. Over the past few decades, new societal requirement haveeme...

  10. Nano-material and method of fabrication

    Science.gov (United States)

    Menchhofer, Paul A; Seals, Roland D; Howe, Jane Y; Wang, Wei

    2015-02-03

    A fluffy nano-material and method of manufacture are described. At 2000.times. magnification the fluffy nanomaterial has the appearance of raw, uncarded wool, with individual fiber lengths ranging from approximately four microns to twenty microns. Powder-based nanocatalysts are dispersed in the fluffy nanomaterial. The production of fluffy nanomaterial typically involves flowing about 125 cc/min of organic vapor at a pressure of about 400 torr over powder-based nano-catalysts for a period of time that may range from approximately thirty minutes to twenty-four hours.

  11. Measurement capability overview in PolyNano

    DEFF Research Database (Denmark)

    Calaon, Matteo; Tosello, Guido; Hansen, Hans Nørgaard

    2012-01-01

    A measurement capability overview has been conducted to evaluate, among the most used instruments in the field of nanometrology, where the PolyNano project should focus its research. The deliverable presents the most relevant instruments to achieve the best possible measurements accuracy matching...... requirements such as low uncertainty, high repeatability and resolution, adequate measuring range and availability among the different project partners. Based on the present measurement capability overview and in relation to the objective of PolyNano to “remove the technology barrier between lab‐scale proof...

  12. Gel nano-particulates against radioactivity

    International Nuclear Information System (INIS)

    Deroin, Ph.

    2004-01-01

    The Argonne research center (USA) has developed a 'super-gel' compound, a polymer close to those used in baby's diapers, which can reach a 90% efficiency in the radioactive decontamination of porous materials, like bricks or concrete. The contaminated materials are sprayed with a mixture of polymer gel and wetting agent with nano-particulates in suspension. Under the action of the wetting agent, radioactivity migrates from the pores to the gel and is trapped by the nano-particulates. The drying and recycling of the gel allows to reduce the volume of radioactive wastes. Short paper. (J.S.)

  13. Magnetic bead detection using nano-transformers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Kwon; Ahn, Doyeol [Institute of Quantum Information Processing and Systems, University of Seoul, 90 Jeonnong, Dongdaemun, Seoul 130-743 (Korea, Republic of); Hwang, Jong Seung; Hwang, Sung Woo, E-mail: dahn@uos.ac.kr [Research Center for Time-domain Nano-functional Devices and School of Electrical Engineering, Korea University, 5-1 Anam, Sungbuk, Seoul 136-701 (Korea, Republic of)

    2010-11-19

    A novel scheme to detect magnetic beads using a nano-scale transformer with a femtoweber resolution is reported. We have performed a Faraday's induction experiment with the nano-transformer at room temperature. The transformer shows the linear output voltage responses to the sinusoidal input current. When magnetic beads are placed on the transformer, the output responses are increased by an amount corresponding to the added magnetic flux from the beads when compared with the case of no beads on the transformer. In this way, we could determine whether magnetic beads are on top of the transformer in a single particle level.

  14. Magnetic bead detection using nano-transformers.

    Science.gov (United States)

    Kim, Hyung Kwon; Hwang, Jong Seung; Hwang, Sung Woo; Ahn, Doyeol

    2010-11-19

    A novel scheme to detect magnetic beads using a nano-scale transformer with a femtoweber resolution is reported. We have performed a Faraday's induction experiment with the nano-transformer at room temperature. The transformer shows the linear output voltage responses to the sinusoidal input current. When magnetic beads are placed on the transformer, the output responses are increased by an amount corresponding to the added magnetic flux from the beads when compared with the case of no beads on the transformer. In this way, we could determine whether magnetic beads are on top of the transformer in a single particle level.

  15. Olefin metathesis in nano-sized systems

    Directory of Open Access Journals (Sweden)

    Denise Méry

    2011-01-01

    Full Text Available The interplay between olefin metathesis and dendrimers and other nano systems is addressed in this mini review mostly based on the authors’ own contributions over the last decade. Two subjects are presented and discussed: (i The catalysis of olefin metathesis by dendritic nano-catalysts via either covalent attachment (ROMP or, more usefully, dendrimer encapsulation – ring closing metathesis (RCM, cross metathesis (CM, enyne metathesis reactions (EYM – for reactions in water without a co-solvent and (ii construction and functionalization of dendrimers by CM reactions.

  16. Improved nano-particle tracking analysis

    International Nuclear Information System (INIS)

    Walker, John G

    2012-01-01

    Nano-particle tracking is a method to estimate a particle size distribution by tracking the movements of individual particles, using multiple images of particles moving under Brownian motion. A novel method to recover a particle size distribution from nano-particle tracking data is described. Unlike a simple histogram-based method, the method described is able to account for the finite number of steps in each particle track and consequently for the measurement uncertainty in the step-length data. Computer simulation and experimental results are presented to demonstrate the performance of the approach compared with the current method. (paper)

  17. Desensitizing nano powders to electrostatic discharge ignition

    International Nuclear Information System (INIS)

    Steelman, Ryan; Daniels, Michael A.

    2015-01-01

    Electrostatic discharge (ESD) is a main cause for ignition in powder media ranging from grain silos to fireworks. Nanoscale particles are orders of magnitude more ESD ignition sensitive than their micron scale counterparts. This study shows that at least 13 vol. % carbon nanotubes (CNT) added to nano-aluminum and nano-copper oxide particles (nAl + CuO) eliminates ESD ignition sensitivity. The CNT act as a conduit for electric energy and directs electric charge through the powder to desensitize the reactive mixture to ignition. For nanoparticles, the required CNT concentration for desensitizing ESD ignition acts as a diluent to quench energy propagation.

  18. Delayed radiation necrosis of the brain simulating a brain tumor

    International Nuclear Information System (INIS)

    Ikeda, Hiroya; Kanai, Nobuhiro; Kamikawa, Kiyoo

    1976-01-01

    Two cases of delayed radiation necrosis of the brain are reported. Case 1 was a 50-year-old man who had right hemiparesis and disorientation 26 months after Linac irradiation (5,000 rad), preceded by an operation for right maxillar carcinoma. A left carotid angiogram demonstrated a left temporal mass lesion, extending to the frontal lobe. Case 2 was a 41-year-old man who had previously had an operation for right intraorbital plasmocytoma, followed by two Co irradiations (6,400 rad, and 5,000 rad). He had the signs and symptoms of intracranial hypertension 36 months after his last irradiation. A left carotid angiogram demonstrated a left temporal mass lesion. Both cases were treated by administration of steroid hormone (which alleviated the signs and symptoms) and by temporal lobectomy. Microscopic examinations showed necrosis of the brain tissues associated with hyaline degeneration of blood vessel walls and perivascular cell infiltration. The signs and symptoms of intracranial hypertension subsided postoperatively. Thirteen other cases the same as ours were collected from literature. They showed the signs and symptoms simulating a brain tumor (like a metastatic brain tumor) after irradiation to extracranial malignant tumors. Diagnosis of radiation necrosis was made by operation or autopsy. A follow-up for a long time is necessary, because the pathological changes in the brain may be progressive and extending in some cases, although decompressive operations for mass lesions give excellent results. (auth.)

  19. Brain injury in sports.

    Science.gov (United States)

    Lloyd, John; Conidi, Frank

    2016-03-01

    Helmets are used for sports, military, and transportation to protect against impact forces and associated injuries. The common belief among end users is that the helmet protects the whole head, including the brain. However, current consensus among biomechanists and sports neurologists indicates that helmets do not provide significant protection against concussion and brain injuries. In this paper the authors present existing scientific evidence on the mechanisms underlying traumatic head and brain injuries, along with a biomechanical evaluation of 21 current and retired football helmets. The National Operating Committee on Standards for Athletic Equipment (NOCSAE) standard test apparatus was modified and validated for impact testing of protective headwear to include the measurement of both linear and angular kinematics. From a drop height of 2.0 m onto a flat steel anvil, each football helmet was impacted 5 times in the occipital area. Skull fracture risk was determined for each of the current varsity football helmets by calculating the percentage reduction in linear acceleration relative to a 140-g skull fracture threshold. Risk of subdural hematoma was determined by calculating the percentage reduction in angular acceleration relative to the bridging vein failure threshold, computed as a function of impact duration. Ranking the helmets according to their performance under these criteria, the authors determined that the Schutt Vengeance performed the best overall. The study findings demonstrated that not all football helmets provide equal or adequate protection against either focal head injuries or traumatic brain injuries. In fact, some of the most popular helmets on the field ranked among the worst. While protection is improving, none of the current or retired varsity football helmets can provide absolute protection against brain injuries, including concussions and subdural hematomas. To maximize protection against head and brain injuries for football players of

  20. The Effect of Nano Loading and Ultrasonic Compounding of EVA/LDPE/Nano-magnesium Hydroxide on Mechanical Properties and Distribution of Nano Particles

    Science.gov (United States)

    Azman, I. A.; Salleh, R. M.; Alauddin, S. M.; Shueb, M. I.

    2018-05-01

    Blends of Ethylene Vinyl Acetate (EVA) and Low-Density Polyethylene (LDPE) are promising composite which have good mechanical properties to environmental stress cracking. However, they lack fire resistant properties, which limits it usage in wire and cable industry. In order to improve flame retardancy ability, a range of nano-magnesium hydroxide (nano-MH) loading which is from 0 phr to maximum of 20 phr with ultrasonic extrusion 0-100 kHz frequencies have been introduced. Ultrasonic extrusion was used to improve the distribution of nano-MH. It was found that, 10 phr of nano loading with 100 kHz ultrasonic assisted has greater tensile strength compared to the nanocomposite without ultrasonication. Further increase of nano MH loading, will decrease the tensile properties. Better elongation at break was observed at10 phr nano-MH with the frequency of 50 kHz. The sample of 20 phr of nanoMH assisted with 50 kHz ultrasonic exhibits good flexural properties while 10 phr of nano-MH without the ultrasonic assisted demonstrates good in izod impact properties. From the evaluation of mechanical properties studied, it was found that 10 phr of nano-MH has shown the best performance among all the samples tested for EVA/LDPE/nano-MH composites. Transmission Electron Microscopy (TEM) has been conducted on 10 phr sample with different frequencies in order to observe the distribution of nano-MH particles. The sample with 100 kHz frequency shows more uniform dispersion of nano-MH in EVA/LDPE composites. This investigation indicates that the ultrasonic technology can enhance the mechanical properties studied as well as the dispersion of nano particles in the composite.

  1. Nano Energy Harvesting with Plasmonic Nano-Antennas: A review of MID-IR Rectenna and Application

    Directory of Open Access Journals (Sweden)

    R. Citroni

    2017-03-01

    Full Text Available Over the past decade, unmanned air vehicles are gaining more and more interest and popularity in particular miniaturized small flight objects named NAVs (Nano Air Vehicles. One of the main considerations when building or buying a drone is the flight time and range. The flight time is nowadays a drawback for miniature unmanned aerial vehicles (UAVs. It is limited to few minutes before requiring a forced recovery to replace exhausted batteries. Currently the batteries are the dominant technology, which possess limited operation in time and energy. The real viability to extending flight time (FT of NAVs is possible exploring new and more disruptive alternative solution able either to recharge a battery, or even to directly power the NAVs during the flight. Plasmonic Nano Energy harvester is an attractive technology to extending the FT extracting the energy in mid-infrared radiation emitted from Earth’s surface with Rectenna tuned to mid-infrared wavelengths (7 –14 um with a peak wavelength of about10um . In this review the concepts emerging from this work identify and suggest how this novel harvester can constantly supply these flying objects for the whole day.

  2. Electrode fabrication for Lithium-ion batteries by intercalating of carbon nano tubes inside nano metric pores of silver foam

    International Nuclear Information System (INIS)

    Khoshnevisan, B.

    2011-01-01

    Here there is an on effort to improve working electrode (Ag + carbon nano tubes) preparation for Li-Ion batteries applications. Nano scaled silver foam with high specific area has been employed as a frame for loading carbon nano tubes by electrophoretic deposition method. In this ground, the prepared electrodes show a very good stability and also charge-discharge cycles reversibility.

  3. Plasmonic graded nano-disks as nano-optical conveyor belt.

    Science.gov (United States)

    Kang, Zhiwen; Lu, Haifei; Chen, Jiajie; Chen, Kun; Xu, Fang; Ho, Ho-Pui

    2014-08-11

    We propose a plasmonic system consisting of nano-disks (NDs) with graded diameters for the realization of nano-optical conveyor belt. The system contains a couple of NDs with individual elements coded with different resonant wavelengths. By sequentially switching the wavelength and polarization of the excitation source, optically trapped target nano-particle can be transferred from one ND to another. The feasibility of such function is verified based on the three-dimensional finite-difference time-domain technique and the Maxwell stress tensor method. Our design may provide an alternative way to construct nano-optical conveyor belt with which target molecules can be delivered between trapping sites, thus enabling many on-chip optofluidic applications.

  4. Report of International NanoSPD Steering Committee and statistics on recent NanoSPD activities

    International Nuclear Information System (INIS)

    Valiev, R Z; Langdon, T G

    2014-01-01

    Abstract. The Université de Lorraine in Metz, France, is the selected site for the 6th International Conference on Nanomaterials by Severe Plastic Deformation (NanoSPD6) following a series of five earlier conferences. This introductory paper reports on several major developments in NanoSPD activities as well as on very recent NanoSPD citation data which confirm the continued growth and expansion of this important research area. Close attention is given to the topics of workshops, conferences and seminars organized during these last three years as well as on books and reviews published prior to the NanoSPD6 conference. A special concern of the committee is in introducing and discussing the appropriate terminology to be applied in this new field of materials science and engineering

  5. Reactive oxygen species-related activities of nano-iron metal and nano-iron oxides.

    Science.gov (United States)

    Wu, Haohao; Yin, Jun-Jie; Wamer, Wayne G; Zeng, Mingyong; Lo, Y Martin

    2014-03-01

    Nano-iron metal and nano-iron oxides are among the most widely used engineered and naturally occurring nanostructures, and the increasing incidence of biological exposure to these nanostructures has raised concerns about their biotoxicity. Reactive oxygen species (ROS)-induced oxidative stress is one of the most accepted toxic mechanisms and, in the past decades, considerable efforts have been made to investigate the ROS-related activities of iron nanostructures. In this review, we summarize activities of nano-iron metal and nano-iron oxides in ROS-related redox processes, addressing in detail the known homogeneous and heterogeneous redox mechanisms involved in these processes, intrinsic ROS-related properties of iron nanostructures (chemical composition, particle size, and crystalline phase), and ROS-related bio-microenvironmental factors, including physiological pH and buffers, biogenic reducing agents, and other organic substances. Copyright © 2014. Published by Elsevier B.V.

  6. TRANSFORMATIONS IN NANO-DIAMONDS WITH FORMATION OF NANO-POROUS SILICON CARBIDE AT HIGH PRESSURE

    Directory of Open Access Journals (Sweden)

    V. N. Kovalevsky

    2010-01-01

    Full Text Available The paper contains investigations on regularities of diamond - silicon carbide composite structure formation at impact-wave excitation. It has been determined that while squeezing a porous blank containing Si (SiC nano-diamond by explosive detonation products some processes are taking place such as diamond nano-particles consolidation, reverse diamond transition into graphite, fragments formation from silicon carbide. A method for obtaining high-porous composites with the presence of ultra-disperse diamond particles has been developed. Material with three-dimensional high-porous silicon-carbide structure has been received due to nano-diamond graphitation at impact wave transmission and plastic deformation. The paper reveals nano-diamonds inverse transformation into graphite and its subsequent interaction with the silicon accompanied by formation of silicon-carbide fragments with dimensions of up to 100 nm.

  7. Every which way – nanos gene regulation in echinoderms

    OpenAIRE

    Oulhen, Nathalie; Wessel, Gary M.

    2014-01-01

    Nanos is an essential factor of germ line success in all animals tested. This gene encodes a Zn-finger RNA-binding protein that in complex with its partner pumilio, binds to and changes the fate of several known transcripts. We summarize here the documented functions of nanos in several key organisms, and then emphasize echinoderms as a working model for how nanos expression is regulated. Nanos presence outside of the target cells is often detrimental to the animal, and in sea urchins, nanos ...

  8. Every which way – nanos gene regulation in echinoderms

    Science.gov (United States)

    Oulhen, Nathalie; Wessel, Gary M.

    2014-01-01

    Nanos is an essential factor of germ line success in all animals tested. This gene encodes a Zn-finger RNA-binding protein that in complex with its partner pumilio, binds to and changes the fate of several known transcripts. We summarize here the documented functions of nanos in several key organisms, and then emphasize echinoderms as a working model for how nanos expression is regulated. Nanos presence outside of the target cells is often detrimental to the animal, and in sea urchins, nanos expression appears to be regulated at every step of transcription, and post-transcriptional activity, making this gene product exciting, every which way. PMID:24376110

  9. Lifetime of Nano-Structured Black Silicon for Photovoltaic Applications

    DEFF Research Database (Denmark)

    Plakhotnyuk, Maksym; Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk

    2016-01-01

    In this work, we present recent results of lifetime optimization for nano-structured black silicon and its photovoltaic applications. Black silicon nano-structures provide significant reduction of silicon surface reflection due to highly corrugated nanostructures with excellent light trapping pro......, respectively. This is promising for use of black silicon RIE nano-structuring in a solar cell process flow......In this work, we present recent results of lifetime optimization for nano-structured black silicon and its photovoltaic applications. Black silicon nano-structures provide significant reduction of silicon surface reflection due to highly corrugated nanostructures with excellent light trapping...

  10. Functionally Graded Materials using Plasma Spray with Nano Structured Ceramic

    International Nuclear Information System (INIS)

    Sioh, E L; Tok, A I Y

    2013-01-01

    In this paper, nano structured FGM was fabricated using DC plasma spray technique. Nano structured and micro structured powder were used as the feeding powder with steel substrate. The spray parameters was optimized and characterisation of nano-ceramic FGM and micro-ceramic FGM were done using bending test and micro-hardness test. Experimental results have shown that the nano-structured FGM exhibit 20% improvement flexure strength and 10% in hardness. A comparison was made between sintered micro ceramic tile and nano ceramic FGM using simple drop test method.

  11. Averaging operations on matrices

    Indian Academy of Sciences (India)

    2014-07-03

    Jul 3, 2014 ... Role of Positive Definite Matrices. • Diffusion Tensor Imaging: 3 × 3 pd matrices model water flow at each voxel of brain scan. • Elasticity: 6 × 6 pd matrices model stress tensors. • Machine Learning: n × n pd matrices occur as kernel matrices. Tanvi Jain. Averaging operations on matrices ...

  12. Nano-scale Materials and Nano-technology Processes in Environmental Protection

    International Nuclear Information System (INIS)

    Vissokov, Gh; Tzvetkoff, T.

    2003-01-01

    A number of environmental and energy technologies have benefited substantially from nano-scale technology: reduced waste and improved energy efficiency; environmentally friendly composite structures; waste remediation; energy conversion. In this report examples of current achievements and paradigm shifts are presented: from discovery to application; a nano structured materials; nanoparticles in the environment (plasma chemical preparation); nano-porous polymers and their applications in water purification; photo catalytic fluid purification; hierarchical self-assembled nano-structures for adsorption of heavy metals, etc. Several themes should be considered priorities in developing nano-scale processes related to environmental management: 1. To develop understanding and control of relevant processes, including protein precipitation and crystallisation, desorption of pollutants, stability of colloidal dispersion, micelle aggregation, microbe mobility, formation and mobility of nanoparticles, and tissue-nanoparticle interaction. Emphasis should be given to processes at phase boundaries (solid-liquid, solid-gas, liquid-gas) that involve mineral and organic soil components, aerosols, biomolecules (cells, microbes), bio tissues, derived components such as bio films and membranes, and anthropogenic additions (e.g. trace and heavy metals); 2. To carry out interdisciplinary research that initiates Noel approaches and adopts new methods for characterising surfaces and modelling complex systems to problems at interfaces and other nano-structures in the natural environment, including those involving biological or living systems. New technological advances such as optical traps, laser tweezers, and synchrotrons are extending examination of molecular and nano-scale processes to the single-molecule or single-cell level; 3. To integrate understanding of the roles of molecular and nano-scale phenomena and behaviour at the meso- and/or macro-scale over a period of time

  13. Exfoliated β-Ga2O3 nano-belt field-effect transistors for air-stable high power and high temperature electronics.

    Science.gov (United States)

    Kim, Janghyuk; Oh, Sooyeoun; Mastro, Michael A; Kim, Jihyun

    2016-06-21

    This study demonstrated the exfoliation of a two-dimensional (2D) β-Ga2O3 nano-belt and subsequent processing into a thin film transistor structure. This mechanical exfoliation and transfer method produces β-Ga2O3 nano-belts with a pristine surface as well as a continuous defect-free interface with the SiO2/Si substrate. This β-Ga2O3 nano-belt based transistor displayed an on/off ratio that increased from approximately 10(4) to 10(7) over the operating temperature range of 20 °C to 250 °C. No electrical breakdown was observed in our measurements up to VDS = +40 V and VGS = -60 V between 25 °C and 250 °C. Additionally, the electrical characteristics were not degraded after a month-long storage in ambient air. The demonstration of high-temperature/high-voltage operation of quasi-2D β-Ga2O3 nano-belts contrasts with traditional 2D materials such as transition metal dichalcogenides that intrinsically have limited temperature and power operational envelopes owing to their narrow bandgap. This work motivates the application of 2D β-Ga2O3 to high power nano-electronic devices for harsh environments such as high temperature chemical sensors and photodetectors as well as the miniaturization of power circuits and cooling systems in nano-electronics.

  14. Nano-materials for solar energy conversion

    International Nuclear Information System (INIS)

    Davenas, J.; Boiteux, G.; Ltaief, A.; Barlier, V.

    2006-01-01

    Nano-materials present an important development potential in the field of photovoltaic conversion in opening new outlooks in the reduction of the solar energy cost. The organic or hybrid solar cells principle is based on the electron-hole pairs dissociation, generated under solar radiation on a conjugated polymer, by chemical species acting as electrons acceptors. The two ways based on fullerenes dispersion or on TiO 2 particles in a semi-conductor polymer (MEH-PPV, PVK) are discussed. The acceptors concentration is high in order to allow the conduction of the electrons on a percolation way, the polymer providing the holes conduction. A new preparation method of the mixtures MEH-PPV/fullerenes based on the use of specific solvents has allowed to produce fullerenes having nano-metric sizes ranges. It has then been possible to decrease the fullerenes concentration allowing the dissociation and the transport of photoinduced charges. The way based on the in-situ generation of TiO 2 from an organometallic precursor has allowed to obtain dispersions of nano-metric inorganic particles. The optimization of the photovoltaic properties of these nano-composites requires a particular adjustment of their composition and size ranges leading to a better control of the synthesis processes. (O.M.)

  15. Scaling laws for nanoFET sensors

    International Nuclear Information System (INIS)

    Zhou Fushan; Wei Qihuo

    2008-01-01

    The sensitive conductance change of semiconductor nanowires and carbon nanotubes in response to the binding of charged molecules provides a novel sensing modality which is generally denoted as nanoFET sensors. In this paper, we study the scaling laws of nanoplate FET sensors by simplifying nanoplates as random resistor networks with molecular receptors sitting on lattice sites. Nanowire/tube FETs are included as the limiting cases where the device width goes small. Computer simulations show that the field effect strength exerted by the binding molecules has significant impact on the scaling behaviors. When the field effect strength is small, nanoFETs have little size and shape dependence. In contrast, when the field effect strength becomes stronger, there exists a lower detection threshold for charge accumulation FETs and an upper detection threshold for charge depletion FET sensors. At these thresholds, the nanoFET devices undergo a transition between low and large sensitivities. These thresholds may set the detection limits of nanoFET sensors, while they could be eliminated by designing devices with very short source-drain distance and large width

  16. Sintering characteristics of nano-ceramic coatings

    NARCIS (Netherlands)

    de Hosson, J.T.M.; Popma, R.

    2003-01-01

    This paper concentrates on sintering characteristics of nano-sized ceramic SiO2 particles. The sintering process is studied as a function of temperature using a conventional furnace and using a laser beam. The underlying idea is to combine the nanoceramic sol-gel concept with inkjet technology and

  17. Metal nano-film resistivity chemical sensor

    Czech Academy of Sciences Publication Activity Database

    Podešva, Pavel; Foret, František

    2016-01-01

    Roč. 37, č. 3 (2016), s. 392-397 ISSN 0173-0835 R&D Projects: GA ČR(CZ) GBP206/12/G014 Institutional support: RVO:68081715 Keywords : adsorption * chemiresistor * nano-film * thiol binding * thiol sensing Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.744, year: 2016

  18. Nanotechnology Environmental and Health Implications (NEHI) | Nano

    Science.gov (United States)

    Skip main navigation Nano.gov Nanotechnology 101 What It Is and How It Works What is Nanotechnology What's So Special about the Nanoscale? NNI Accomplishments NNI Accomplishments Archive Nanotechnology Timeline Frequently Asked Questions Glossary Nanotechnology and You Benefits and Applications Networks and

  19. Immuno compatibility of Bacteriophages as Nano medicines

    International Nuclear Information System (INIS)

    Kaur, T.; Nafissi, N.; Wasfi, O.; Sheldon, K.; Wettig, Sh.; Slavcev, R.

    2012-01-01

    Bacteriophage-based medical research provides the opportunity to develop targeted nano medicines with heightened efficiency and safety profiles. Filamentous phages also can and have been formulated as targeted drug-delivery nano medicines, and phage may also serve as promising alternatives/complements to antibiotics. Over the past decade the use of phage for both the prophylaxis and the treatment of bacterial infection, has gained special significance in view of a dramatic rise in the prevalence of antibiotic resistance bacterial strains. Two potential medical applications of phages are the treatment of bacterial infections and their use as immunizing agents in diagnosis and monitoring patients with immunodeficiencies. Recently, phages have been employed as gene-delivery vectors (phage nano medicine), for nearly half a century as tools in genetic research, for about two decades as tools for the discovery of specific target-binding proteins and peptides, and for almost a decade as tools for vaccine development. As phage applications to human therapeutic development grow at an exponential rate, it will become essential to evaluate host immune responses to initial and repetitive challenges by therapeutic phage in order to develop phage therapies that offer suitable utility. This paper examines and discusses phage nano medicine applications and the immunomodulatory effects of bacteriophage exposure and treatment modalities.

  20. Replication Fidelity Assessment in Nano Moulding

    DEFF Research Database (Denmark)

    Calaon, Matteo; Hansen, Hans Nørgaard; Tosello, Guido

    2015-01-01

    to remove technology barrier between lab-scale proof-of-principle and high-volume low-cost production of nanotechnology-based products. In the current study research work has been devoted to develop methods and approaches to process chain characterization for final polymer micro and nano structures...

  1. Structural stability of nano-sized clusters

    NARCIS (Netherlands)

    De Hosson, JTM; Palasantzas, G; Vystavel, T; Koch, S; Ovidko,; Pande, CS; Krishnamoorti, R; Lavernia, E; Skandan, G

    2004-01-01

    This contribution presents challenges to control the microstructure in nano-structured materials via a relatively new approach, i.e. using a so-called nanocluster source. An important aspect is that the cluster size distribution is monodisperse and that the kinetic energy of the clusters during

  2. Mechanics over micro and nano scales

    CERN Document Server

    Chakraborty, Suman

    2011-01-01

    Discusses the fundaments of mechanics over micro and nano scales in a level accessible to multi-disciplinary researchers, with a balance of mathematical details and physical principles Covers life sciences and chemistry for use in emerging applications related to mechanics over small scales Demonstrates the explicit interconnection between various scale issues and the mechanics of miniaturized systems

  3. We Scream for Nano Ice Cream

    Science.gov (United States)

    Jones, M. Gail; Krebs, Denise L.; Banks, Alton J.

    2011-01-01

    There is a wide range of new products emerging from nanotechnology, and "nano ice cream" is an easy one that you can use to teach topics from surface area to volume applications. In this activity, students learn how ice cream can be made smoother and creamier tasting through nanoscience. By using liquid nitrogen to cool the cream mixture, students…

  4. Nano spray drying for encapsulation of pharmaceuticals.

    Science.gov (United States)

    Arpagaus, Cordin; Collenberg, Andreas; Rütti, David; Assadpour, Elham; Jafari, Seid Mahdi

    2018-05-17

    Many pharmaceuticals such as pills, capsules, or tablets are prepared in a dried and powdered form. In this field, spray drying plays a critical role to convert liquid pharmaceutical formulations into powders. In addition, in many cases it is necessary to encapsulate bioactive drugs into wall materials to protect them against harsh process and environmental conditions, as well as to deliver the drug to the right place and at the correct time within the body. Thus, spray drying is a common process used for encapsulation of pharmaceuticals. In view of the rapid progress of nanoencapsulation techniques in pharmaceutics, nano spray drying is used to improve drug formulation and delivery. The nano spray dryer developed in the recent years provides ultrafine powders at nanoscale and high product yields. In this paper, after explaining the concept of nano spray drying and understanding the key elements of the equipment, the influence of the process parameters on the final powders properties, like particle size, morphology, encapsulation efficiency, drug loading and release, will be discussed. Then, numerous application examples are reviewed for nano spray drying and encapsulation of various drugs in the early stages of product development along with a brief overview of the obtained results and characterization techniques. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. A new nano-biophotonics toolbox

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Bañas, Andrew Rafael; Palima, Darwin

    The science fiction inspired shrinking of macro-scale robotic manipulation and handling down to the micro- and nano-scale regime open new doors for exploiting the forces and torques of light for micro- and nanobiologic probing, actuation and control. A generic approach for optimizing light...

  6. Nano technologies for Biosensor and Bio chip

    International Nuclear Information System (INIS)

    Kim, I.M.; Park, T.J.; Paskaleva, E.E.; Sun, F.; Seo, J.W.; Mehta, K.K.

    2015-01-01

    The bio sensing devices are characterized by their biological receptors, which have specificity to their corresponding analytes. These analytes are a vast and diverse group of biological molecules, DNAs, proteins (such as antibodies), fatty acids, or entire biological systems, such as pathogenic bacteria, viruses, cancerous cells, or other living organisms. A main challenge in the development of biosensor applications is the efficient recognition of a biological signal in a low signal-to-noise ratio environment, and its transduction into an electrochemical, optical, or other signals. The advent of nano material technology greatly increased the potential for achieving exquisite sensitivity of such devises, due to the innate high surface-to-volume ratio and high reactivity of the nano material. The second major challenge facing the biosensor application, that of sca lability, is addressed by multiplexing and miniaturizing of the biosensor devises into a bio chip. In recent years, biosensor and bio chip technologies have made significant progress by taking advantages of diverse kinds of nano materials that are derived from nano technology

  7. An Experimental study of Fullerene (C60) Nano-fluids on Pool Boiling Conditions

    International Nuclear Information System (INIS)

    Melani, Ai; Shin, Byoong Su; Chang, Soon Heung

    2009-01-01

    Critical heat flux (CHF) is directly related to the performance of the system since CHF limits the heat transfer of a heat transfer system. Significant enhancement of CHF allows reliable operation of equipment with more margins to operational limit and more economic cost saving. The previous results show that the nano-fluids significantly enhanced pool boiling CHF compared to pure water. It was supposed that CHF enhancement was due to increased thermal conductivity of fluids, change of bubble shape and behavior, and nano-particle coating of the boiling surface. The previous researches also show that mainly the pool boiling experiment was employed metal particles. Fullerene (C 60 ) is a novel carbon allotrope that was first discovered in 1985 by a winner noble 'Sir Harold W.Kroto, Richard E. Smalley and Robert F.Curl Jr'. In this study we report the first CHF experiment in pool boiling conditions using Fullerene (C 60 ) nanofluids

  8. Brain Fog

    Science.gov (United States)

    ... relationship with your doctor(s): • Always report changes in cognition/memory and mood (depression, anxiety). • Make sure your physician ... joint pain. • Exercise regularly. Adequate physical exercise enhances cognition/memory. • Train the Brain! “If you don’t use ...

  9. Robot brains

    NARCIS (Netherlands)

    Babuska, R.

    2011-01-01

    The brain hosts complex networks of neurons that are responsible for behavior in humans and animals that we generally call intelligent. I is not easy to give an exact definition of intelligence – for the purpose of this talk it will suffice to say that we refer to intelligence as a collection of

  10. Manipulation and functionalization of nano-tubes: application to boron nitride nano-tubes

    International Nuclear Information System (INIS)

    Maguer, A.

    2007-01-01

    This PhD work is divided into two parts dealing with boron nitride (BNNT) and carbon nano-tubes. The first part is about synthesis, purification and chemical functionalization of BNNT. Single-walled BNNT are synthesized by LASER ablation of a hBN target. Improving the synthesis parameters first allowed us to limit the byproducts (hBN, boric acid). A specific purification process was then developed in order to enrich the samples in nano-tubes. Purified samples were then used to develop two new chemical functionalization methods. They both involve chemical molecules that present a high affinity towards the BN network. The use of long chain-substituted quinuclidines and borazines actually allowed the solubilization of BNNT in organic media. Purification and functionalization were developed for single-walled BNNT and were successfully applied to multi-walled BNNT. Sensibility of boron to thermic neutrons finally gave birth to a study about covalent functionalization possibilities of the network. The second part of the PhD work deals with separation of carbon nano-tubes depending on their properties. Microwave irradiation of carbon nano-tubes first allowed the enrichment of initially polydisperse samples in large diameter nano-tubes. A second strategy involving selective interaction between one type of tubes and fullerene micelles was finally envisaged to selectively solubilize carbon nano-tubes with specific electronic properties. (author) [fr

  11. Transferring metallic nano-island on hydrogen passivated silicon surface for nano-electronics

    International Nuclear Information System (INIS)

    Deng, J; Troadec, C; Joachim, C

    2009-01-01

    In a planar configuration, precise positioning of ultra-flat metallic nano-islands on semiconductor surface opens a way to construct nanostructures for atomic scale interconnects. Regular triangular Au nano-islands have been grown on atomically flat MoS 2 substrates and manipulated by STM to form nanometer gap metal-pads connector for single molecule electronics study. The direct assembly of regular shaped metal nano-islands on H-Si(100) is not achievable. Here we present how to transfer Au triangle nano-islands from MoS 2 onto H-Si(100) in a clean manner. In this experiment, clean MoS 2 substrates are patterned as array of MoS 2 pillars with height of 8 μm. The Au triangle nano-islands are grown on top of the pillars. Successful printing transfer of these Au nano-islands from the MoS 2 pillars to the H-Si(100) is demonstrated.

  12. Convection enhanced delivery of panobinostat (LBH589-loaded pluronic nano-micelles prolongs survival in the F98 rat glioma model

    Directory of Open Access Journals (Sweden)

    Singleton WG

    2017-02-01

    Full Text Available WG Singleton,1,2 AM Collins,3 AS Bienemann,1 CL Killick-Cole,1 HR Haynes,4 DJ Asby,1 CP Butts,5 MJ Wyatt,1 NU Barua,1,2 SS Gill1,2 1Functional Neurosurgery Research Group, School of Clinical Sciences, University of Bristol, 2Department of Neurosurgery, North Bristol NHS Trust, 3Bristol Centre for Functional Nanomaterials, School of Physics, HH Wills Physics Laboratory, 4Brain Tumour Research Group, School of Clinical Sciences, 5School of Chemistry, University of Bristol, Bristol, UKBackground: The pan-histone deacetylase inhibitor panobinostat is a potential therapy for malignant glioma, but it is water insoluble and does not cross the blood–brain barrier when administered systemically. In this article, we describe the in vitro and in vivo efficacy of a novel water-soluble nano-micellar formulation of panobinostat designed for administration by convection enhanced delivery (CED.Materials and methods: The in vitro efficacy of panobinostat-loaded nano-micelles against rat F98, human U87-MG and M059K glioma cells and against patient-derived glioma stem cells was measured using a cell viability assay. Nano-micelle distribution in rat brain was analyzed following acute CED using rhodamine-labeled nano-micelles, and toxicity was assayed using immunofluorescent microscopy and synaptophysin enzyme-linked immunosorbent assay. We compared the survival of the bioluminescent syngenic F98/Fischer344 rat glioblastoma model treated by acute CED of panobinostat-loaded nano-micelles with that of untreated and vehicle-only-treated controls.Results: Nano-micellar panobinostat is cytotoxic to rat and human glioma cells in vitro in a dose-dependent manner following short-time exposure to drug. Fluorescent rhodamine-labelled nano-micelles distribute with a volume of infusion/volume of distribution (Vi/Vd ratio of four and five respectively after administration by CED. Administration was not associated with any toxicity when compared to controls. CED of

  13. Nanoelectromechanical resonator for logic operations

    KAUST Repository

    Kazmi, Syed N. R.

    2017-08-29

    We report an electro-thermally tunable in-plane doubly-clamped nanoelectromechanical resonator capable of dynamically performing NOR, NOT, XNOR, XOR, and AND logic operations. Toward this, a silicon based resonator is fabricated using standard e-beam lithography and surface nanomachining of a highly conductive device layer of a silicon-on-insulator (SOI) wafer. The performance of this logic device is examined at elevated temperatures, ranging from 25 °C to 85 °C, demonstrating its resilience for most of the logic operations; thereby paving the way towards nano-elements-based mechanical computing.

  14. Nano materials for Renewable Energy Storage: Synthesis, Characterization, and Applications

    International Nuclear Information System (INIS)

    Rather, S.U.; Zacharia, R.; Stephan, A.M.; Petrov, L.A.; Nair, J.R.

    2015-01-01

    Nano technology and nano scale materials have been part of human history and in use since centuries. Staining of glass windows hundreds of years ago is one of the examples where people created beautiful works without knowing that they are using nano processing. The beginning of modern era of nano technology dates back to the talk of the Nobel laureate Professor Richard Feynman in There plenty of room at the bottom. Professor Feynman hypothesized that in near future scientists would be able to control and modulate individual molecules and atoms. After a decade, Professor Norio Taniguchi introduced the magical word nano technology. However, in 1981, the introduction of scanning tunnelling microscope enabled the scientists to see the materials in nano scale that propagated the new age of nano technology.

  15. Review on Nano SeleniumProduced by Bacteria

    Directory of Open Access Journals (Sweden)

    LI Ji-xiang

    2014-12-01

    Full Text Available Selenium (Se is a kind of essential trace element for people and animal, while ionic state of selenium is toxic with high concentrations and will cause the selenium pollution. Nano-selenium is stable, nontoxic with higher biological activity. Application of bacteria reducing selenite or selenate to biological nano-selenium has great potential in selenium pollution control and nano-selenium production. This review summarizes the research progress of the red elemental nano-selenium reduced by bacteria including characteristics and application of nano-selenium, effects of carbon and nitrogen source, oxygen, temperature and pH in bacteria nano-selenium production, and molecular mechanisms of nano-selenium reduced by bacteria.

  16. Nano-Fiber Reinforced Enhancements in Composite Polymer Matrices

    Science.gov (United States)

    Chamis, Christos C.

    2009-01-01

    Nano-fibers are used to reinforce polymer matrices to enhance the matrix dependent properties that are subsequently used in conventional structural composites. A quasi isotropic configuration is used in arranging like nano-fibers through the thickness to ascertain equiaxial enhanced matrix behavior. The nano-fiber volume ratios are used to obtain the enhanced matrix strength properties for 0.01,0.03, and 0.05 nano-fiber volume rates. These enhanced nano-fiber matrices are used with conventional fiber volume ratios of 0.3 and 0.5 to obtain the composite properties. Results show that nano-fiber enhanced matrices of higher than 0.3 nano-fiber volume ratio are degrading the composite properties.

  17. Mass transfer in nano-fluids: A review

    International Nuclear Information System (INIS)

    Ashrafmansouri, Seyedeh-Saba; Esfahany, Mohsen Nasr

    2014-01-01

    Growing attention has been recently paid to nano-fluids because of their potential for augmenting transfer processes - i.e., heat and mass transfer. Conflicting results have been reported in the literature on mass transfer in nano-fluids. The aim of this paper is to summarize the literature on mass transfer in nano-fluids stating the conflicts and possible reasons. Literature on mass transfer in nano-fluids has been reviewed in two sections. The first section concentrates on surveying mass diffusivity in nano-fluids while the second section focuses on convective mass transfer in nano-fluids. In each section, published articles, type of nano-fluids used, size and concentration range of nanoparticles, measurement methods, maximum observed enhancement, and suggested mass transport mechanisms are summarized. (authors)

  18. Applying Nano technology to Human Health: Revolution in Biomedical Sciences

    International Nuclear Information System (INIS)

    Shrivastava, S.; Dash, D.

    2009-01-01

    Recent research on bio systems at the nano scale has created one of the most dynamic science and technology domains at the confluence of physical sciences, molecular engineering, biology, biotechnology, and medicine. This domain includes better understanding of living and thinking systems, revolutionary biotechnology processes, synthesis of new drugs and their targeted delivery, regenerative medicine, necrophorum engineering, and developing a sustainable environment. Nano bio systems research is a priority in many countries and its relevance within nano technology is expected to increase in the future. The realisation that the nano scale has certain properties needed to solve important medical challenges and cater to unmet medical needs is driving nano medical research. The present review explores the significance of nano science and latest nano technologies for human health. Addressing the associated opportunities, the review also suggests how to manage far-reaching developments in these areas

  19. Catalytic Fast Pyrolysis of Alcell Lignin with Nano-NiO

    Directory of Open Access Journals (Sweden)

    Jiao Chen

    2015-11-01

    Full Text Available Catalytic fast pyrolysis of Alcell lignin with various additive ratios (5%, 10%, and 15%, mass ratio of nano-NiO was investigated using a horizontal pyrolyzer. Characterization methods, including Fourier transform infrared spectroscopy (FTIR, gas chromatography (GC, gas chromatography coupled with mass spectrometry (GC/MS, and elemental analysis, were utilized to identify the catalytic fast pyrolysis products. The results indicated that the nano-NiO catalyst had remarkable effects on the yield and quality of these products. The formation of gases, especially CO, CO2, and CH4, were greatly promoted when the additive ratio increased, while the formation of bio-char was clearly inhibited. However, when the additive ratio was 10%, the maximum yield of bio-oil (53.09 wt.% was obtained, and the corresponding maximum higher heating value (HHV was 25.33 MJ/kg. Furthermore, nano-NiO caused a large variation in the species of the compounds in bio-oil. Operating with the optimal nano-NiO additive ratio (10%, the carbon conversion rate was 65.50%, and the energy conversion rate was 74.53%.

  20. Preparation and characterization of functionalized cellulose nano crystals with methyl adipoyl chloride used to prepare chitosan grafting nano composite

    International Nuclear Information System (INIS)

    Mesquita, Joao Paulo de; Teixeira, Ivo F.; Donnici, Claudio L.; Pereira, Fabiano V.

    2011-01-01

    Cellulose nano crystals (CNCs) were prepared from eucalyptus pulp and functionalized with methyl adipoyl chloride. The nano materials were characterized by different techniques including FTIR, 1H NMR and XRD which showed that the functionalization occurs only on the surface of the nano structures without change in crystalline structure of the nanoparticles. The new-functionalized CNCs were used as reinforcement in the preparation of a nano composite with chitosan, through the formation of a covalent bond between the nano filler and matrix. Preliminary results of mechanical tests indicate an improvement in tensile strength and increase in deformation of chitosan. (author)

  1. Understanding Brain Tumors

    Science.gov (United States)

    ... to Know About Brain Tumors . What is a Brain Tumor? A brain tumor is an abnormal growth
 ... Tumors” from Frankly Speaking Frankly Speaking About Cancer: Brain Tumors Download the full book Questions to ask ...

  2. Brain tumor - children

    Science.gov (United States)

    ... children; Neuroglioma - children; Oligodendroglioma - children; Meningioma - children; Cancer - brain tumor (children) ... The cause of primary brain tumors is unknown. Primary brain tumors may ... (spread to nearby areas) Cancerous (malignant) Brain tumors ...

  3. Brain Tumors (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Brain Tumors KidsHealth / For Parents / Brain Tumors What's in ... radiation therapy or chemotherapy, or both. Types of Brain Tumors There are many different types of brain ...

  4. Brain and Nervous System

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Brain and Nervous System KidsHealth / For Parents / Brain and ... healthy, and remove waste products. All About the Brain The brain is made up of three main ...

  5. Nano-dot and nano-pit fabrication on a GaAs substrate by a pulse applied AFM

    International Nuclear Information System (INIS)

    Kim, H C; Yu, J S; Ryu, S H

    2012-01-01

    The nano-patterning characteristics of GaAs is investigated using a pulse applied atomic force microscope (AFM). Very short range voltage pulses of micro to nano-seconds’ duration are applied to a conductive diamond-coated silicon (Si) tip in contact mode, to regulate the created feature size. The effects of pulse conditions such as pulse voltage, duration, frequency, offset voltage, anodization time, and applied tip pressure on nano-dot generation are characterized, based on the experiments. An interesting phenomenon, nano-pit creation instead of nano-dot creation, is observed when the applied pulse duration is less than 100 μs. Pulse frequency and offset voltage are also involved in nano-pit generation. The electrical spark discharge between the tip and the GaAs's surface is the most probable cause of the nano-pit creation and its generation mechanism is explained by considering the relevant pulse parameters. Nano-pits over 15 nm in depth are acquired on the GaAs substrate by adjusting the pulse conditions. This research facilitates the fabrication of more complex nano-structures on semiconductor materials since nano-dots and nano-pits could be easily made without any additional post-processes. (paper)

  6. A Novel Silicon-based Wideband RF Nano Switch Matrix Cell and the Fabrication of RF Nano Switch Structures

    Directory of Open Access Journals (Sweden)

    Yi Xiu YANG

    2011-12-01

    Full Text Available This paper presents the concept of RF nano switch matrix cell and the fabrication of RF nano switch. The nano switch matrix cell can be implemented into complex switch matrix for signal routing. RF nano switch is the decision unit for the matrix cell; in this research, it is fabricated on a tri-layer high-resistivity-silicon substrate using surface micromachining approach. Electron beam lithography is introduced to define the pattern and IC compatible deposition process is used to construct the metal layers. Silicon-based nano switch fabricated by IC compatible process can lead to a high potential of system integration to perform a cost effective system-on-a-chip solution. In this paper, simulation results of the designed matrix cell are presented; followed by the details of the nano structure fabrication and fabrication challenges optimizations; finally, measurements of the fabricated nano structure along with analytical discussions are also discussed.

  7. The Creative Brain.

    Science.gov (United States)

    Herrmann, Ned

    1982-01-01

    Outlines the differences between left-brain and right-brain functioning and between left-brain and right-brain dominant individuals, and concludes that creativity uses both halves of the brain. Discusses how both students and curriculum can become more "whole-brained." (Author/JM)

  8. The therapeutic effect of nano-encapsulated and nano-emulsion forms of carvacrol on experimental liver fibrosis.

    Science.gov (United States)

    Hussein, Jihan; El-Banna, Mona; Mahmoud, Khaled F; Morsy, Safaa; Abdel Latif, Yasmin; Medhat, Dalia; Refaat, Eman; Farrag, Abdel Razik; El-Daly, Sherien M

    2017-06-01

    The present study aimed to compare the therapeutic efficiency of nano-encapsulated and nano-emulsion carvacrol administration on liver injury in thioacetamide (TAA) treated rats. To fulfill our target, we used sixty male albino rats classified into six groups as follow: control, nano-encapsulated carvacrol, nano-emulsion carvacrol, thioacetamide, treated nano-encapsulated carvacrol and treated nano-emulsion carvacrol groups. Blood samples were collected from all groups and the separated serum was used for analysis of the following biochemical parameters; aspartate aminotransferase (AST), alanine aminotransferase (ALT), S100 B protein, alpha fetoprotein (AFP) and caspase-3. The levels of malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (NO), monocyte chemoattractant protein-1(MCP-1) and hydroxyproline content were all evaluated in liver tissue homogenate. Histopathological examinations for liver tissues were also performed. Thioacetamide induced hepatic damage in rats as revealed by the significant increase in the levels of serum ALT, AST and produced oxidative stress as displayed by the significant elevation in the levels of hepatic MDA and NO concomitant with a significant decrease in GSH. In addition, thioacetamide significantly increased serum S100B protein, alpha fetoprotein and caspase-3 along with hepatic MCP-1 and hydroxyproline; these results were confirmed by the histopathological investigation. In contrast, nano-encapsulated and nano-emulsion carvacrol were able to ameliorate these negative changes in the thioacetamide injected rats. However, the effect of the nano-encapsulated form of carvacrol was more prominent than the nano-emulsion form. Nano-encapsulated and nano-emulsion carvacrol can ameliorate thioacetamide induced liver injury. These results could be attributed to the potential anti-inflammatory, antioxidant, and anti-apoptotic activities of carvacrol in addition to the effectiveness of the encapsulation technique that can protect

  9. Ceramic compositions based on nano forsterite/nano magnesium aluminate spinel powders

    International Nuclear Information System (INIS)

    Khattab, R.M.; Wahsh, M.M.S.; Khalil, N.M.

    2015-01-01

    According to the wide applications in the field of chemical and engineering industries, forsterite (Mg_2SiO_4)/spinel (MgAl_2O_4) ceramic compositions were the matter of interest of several research works during the last three decades. This work aims at preparation and characterization of improved ceramic bodies based on forsterite and spinel nano powders through controlling the forsterite and spinel contents in the prepared mixes. These prepared ceramic compositions have been investigated through measuring the densification parameters, cold crushing strength as well as volume resistively. Nano spinel was added from 0 to 30 mass% on expense of nano forsterite matrix and fired at 1550 °C for 2 h. The phase composition of the fired samples was examined using x-ray diffraction (XRD) technique. The microstructure of some selected samples was shown using scanning electron microscope (SEM). A pronounced improvement in the sintering, mechanical properties and volume resistively were achieved with increasing of nano spinel addition up to 15 mass%. This is due to the improvement in the matrix of the prepared forsterite/spinel bodies as a result of well distribution of spinel in the forsterite matrix as depicted by SEM analysis. - Highlights: • Ceramic compositions based on nano forsterite/nano-MgAl_2O_4 spinel were synthesized. • CCS was improved (333.78 MPa) through 15 mass% of nano-MgAl_2O_4 spinel addition. • Volume resistivity was enhanced to 203*10"1"3 Ohm cm with 15 mass% of spinel addition. • Beyond 15 mass% spinel, CCS and volume resistivity were decreased.

  10. Nano-structural characteristics and optical properties of silver chiral nano-flower sculptured thin films

    Energy Technology Data Exchange (ETDEWEB)

    Savaloni, Hadi, E-mail: savaloni@khayam.ut.ac.ir [Department of Physics, University of Tehran, North-Kargar Street, Tehran (Iran, Islamic Republic of); Haydari-Nasab, Fatemh; Malmir, Mariam [Department of Physics, University of Tehran, North-Kargar Street, Tehran (Iran, Islamic Republic of)

    2011-08-15

    Silver chiral nano-flowers with 3-, 4- and 5-fold symmetry were produced using oblique angle deposition method in conjunction with the rotation of sample holder with different speeds at different sectors of each revolution corresponding to symmetry order of the acquired nano-flower. Atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM), were employed to obtain morphology and nano-structure of the films. Optical characteristics of silver chiral nano-flower thin films were obtained using single beam spectrophotometer with both s- and p-polarization incident light at 30{sup o} and 70{sup o} incidence angles and at different azimuthal angles ({phi}). Optical spectra showed both TM (TDM (transverse dipole mode) and TQM (transverse quadruple mode)) and LM (longitudinal mode) Plasmon resonance peaks. For 3- and 4-fold symmetry chiral nano-flowers the s-polarization extinction spectra obtained at different azimuthal angles did not show significant change in the Plasmon peak position while 5-fold symmetry chiral nano-flower showed a completely different behavior, which may be the result of increased surface anisotropy, so when the {phi} angle is changed the s-polarization response from the surface can change more significantly than that for lower symmetries. In general, for 3-, 4- and 5-fold symmetry chiral nano-flowers a sharp peak at lower wavelengths (<450 nm) is observed in the s-polarization spectra, while in addition to this peak a broad peak at longer wavelengths (i.e., LM) observed in the p-polarization spectra, which is more dominant for 70{sup o} incidence angle.

  11. Brain imaging

    International Nuclear Information System (INIS)

    Greenfield, L.D.; Bennett, L.R.

    1976-01-01

    Imaging with radionuclides should be used in a complementary fashion with other neuroradiologic techniques. It is useful in the early detection and evaluation of intracranial neoplasm, cerebrovascular accident and abscess, and in postsurgical follow-up. Cisternography yields useful information about the functional status of cerebrospinal fluid pathways. Computerized axial tomography is a new technique of great promise that produced a cross-sectional image of the brain

  12. Brain imaging

    International Nuclear Information System (INIS)

    Bradshaw, J.R.

    1989-01-01

    This book presents a survey of the various imaging tools with examples of the different diseases shown best with each modality. It includes 100 case presentations covering the gamut of brain diseases. These examples are grouped according to the clinical presentation of the patient: headache, acute headache, sudden unilateral weakness, unilateral weakness of gradual onset, speech disorders, seizures, pituitary and parasellar lesions, sensory disorders, posterior fossa and cranial nerve disorders, dementia, and congenital lesions

  13. Interaction of NANOS2 and NANOS3 with different components of the CNOT complex may contribute to the functional differences in mouse male germ cells

    Directory of Open Access Journals (Sweden)

    Atsushi Suzuki

    2014-11-01

    Full Text Available NANOS2 and NANOS3 belong to the Nanos family of proteins that contain a conserved zinc finger domain, which consists of two consecutive CCHC-type zinc finger motifs, and contribute to germ cell development in mice. Previous studies indicate that there are redundant and distinct functions of these two proteins. NANOS2 rescues NANOS3 functions in the maintenance of primordial germ cells, whereas NANOS3 fails to replace NANOS2 functions in the male germ cell pathway. However, the lack of a conditional allele of Nanos3 has hampered delineation of each contribution of NANOS2 and NANOS3 to the male germ cell pathway. In addition, the molecular mechanism underlying the distinct functions of these proteins remains unexplored. Here, we report an unexpected observation of a transgenic mouse line expressing a NANOS2 variant harboring mutations in the zinc finger domain. Transcription of Nanos2 and Nanos3 was strongly compromised in the presence of this transgene, which resulted in the mimicking of the Nanos2/Nanos3 double-null condition in the male gonad. In these transgenic mice, P-bodies involved in RNA metabolism had disappeared and germ cell differentiation was more severely affected than that in Nanos2-null mice, indicating that NANOS3 partially substitutes for NANOS2 functions. In addition, similar to NANOS2, we found that NANOS3 associated with the CCR4-NOT deadenylation complex but via a direct interaction with CNOT8, unlike CNOT1 in the case of NANOS2. This alternate interaction might account for the molecular basis of the functional redundancy and differences in NANOS2 and NANOS3 functions.

  14. Radionuclidr diagnosis of brain tumors, brain inflammatory and traumatic lesions

    International Nuclear Information System (INIS)

    Badmaev, K.N.; Mel'kishev, V.F.; Dement'ev, E.V.; Svetlova, N.L.

    1982-01-01

    A complex of problems of radionuclide diagnosis of central nervous system diseases including tumors, traumas, vascular lessons, inflammatory processes is considered. The principles, technique and results of radionuclide xintigraphy of a tumor, depending on its localization are given. Radioindication of brain tumours in the operation is given

  15. Theranastic USPIO-loaded microbubbles for mediating and monitoring blood-brain barrier permeation

    NARCIS (Netherlands)

    Lammers, Twan Gerardus Gertudis Maria; Koczera, Patrick; Fokong, Stanley; Gremse, Felix; Ehling, Josef; Vogt, Michael; Pich, Andrij; Storm, Gerrit; van Zandvoort, Marc; Kiessling, Fabian

    2015-01-01

    Efficient and safe drug delivery across the blood-brain barrier (BBB) remains one of the major challenges of biomedical and (nano-) pharmaceutical research. Here, it is demonstrated that poly(butyl cyanoacrylate)-based microbubbles (MB), carrying ultrasmall superparamagnetic iron oxide (USPIO)

  16. Theranostic USPIO-loaded microbubbles for mediating and monitoring blood-brain barrier permeation

    NARCIS (Netherlands)

    Lammers, Twan; Koczera, Patrick; Fokong, Stanley; Gremse, Felix; Ehling, Josef; Vogt, Michael; Pich, Andrij; Storm, G; Van Zandvoort, Marc; Kiessling, Fabian

    2015-01-01

    Efficient and safe drug delivery across the blood-brain barrier (BBB) remains one of the major challenges of biomedical and (nano-) pharmaceutical research. Here, it is demonstrated that poly(butyl cyanoacrylate)-based microbubbles (MB), carrying ultrasmall superparamagnetic iron oxide (USPIO)

  17. Quantitative Analysis of Nanoparticle Transport through in Vitro Blood-Brain Barrier Models

    NARCIS (Netherlands)

    Åberg, Christoffer

    2016-01-01

    Nanoparticle transport through the blood-brain barrier has received much attention of late, both from the point of view of nano-enabled drug delivery, as well as due to concerns about unintended exposure of nanomaterials to humans and other organisms. In vitro models play a lead role in efforts to

  18. Graphene nano-devices and nano-composites for structural, thermal and sensing applications

    Science.gov (United States)

    Yavari, Fazel

    In this dissertation we have developed graphene-based nano-devices for applications in integrated circuits and gas sensors; as well as graphene-based nano-composites for applications in structures and thermal management. First, we have studied the bandgap of graphene for semiconductor applications. Graphene as a zero-bandgap material cannot be used in the semiconductor industry unless an effective method is developed to open the bandgap in this material. We have demonstrated that a bandgap of 0.206 eV can be opened in graphene by adsorption of water vapor molecules on its surface. Water molecules break the molecular symmetries of graphene resulting in a significant bandgap opening. We also illustrate that the lack of bandgap in graphene can be used to our advantage by making sensors that are able to detect low concentrations of gas molecules mixed in air. We have shown that 1-2 layers of graphene synthesized by chemical vapor deposition enables detection of trace amounts of NO 2 and NH3 in air at room temperature and atmospheric pressure. The gas species are detected by monitoring changes in electrical resistance of the graphene film due to gas adsorption. The sensor response time is inversely proportional to the gas concentration. Heating the film expels chemisorbed molecules from the graphene surface enabling reversible operation. The detection limits of ~100 parts-per-billion (ppb) for NO2 and ~500 ppb for NH3 obtained using this device are markedly superior to commercially available NO2 and NH3 detectors. This sensor is fabricated using individual graphene sheets that are exquisitely sensitive to the chemical environment. However, the fabrication and operation of devices that use individual nanostructures for sensing is complex, expensive and suffers from poor reliability due to contamination and large variability from sample-to-sample. To overcome these problems we have developed a gas sensor based on a porous 3D network of graphene sheets called graphene foam

  19. Flame Retardant Effect of Nano Fillers on Polydimethylsiloxane Composites.

    Science.gov (United States)

    Jagdale, Pravin; Salimpour, Samera; Islam, Md Hujjatul; Cuttica, Fabio; Hernandez, Francisco C Robles; Tagliaferro, Alberto; Frache, Alberto

    2018-02-01

    Polydimethylsiloxane has exceptional fire retardancy characteristics, which make it a popular polymer in flame retardancy applications. Flame retardancy of polydimethylsiloxane with different nano fillers was studied. Polydimethylsiloxane composite fire property varies because of the shape, size, density, and chemical nature of nano fillers. In house made carbon and bismuth oxide nano fillers were used in polydimethylsiloxane composite. Carbon from biochar (carbonised bamboo) and a carbon by-product (carbon soot) were selected. For comparative study of nano fillers, standard commercial multiwall carbon nano tubes (functionalised, graphitised and pristine) as nano fillers were selected. Nano fillers in polydimethylsiloxane positively affects their fire retardant properties such as total smoke release, peak heat release rate, and time to ignition. Charring and surface ceramization are the main reasons for such improvement. Nano fillers in polydimethylsiloxane may affect the thermal mobility of polymer chains, which can directly affect the time to ignition. The study concludes that the addition of pristine multiwall carbon nano tubes and bismuth oxide nano particles as filler in polydimethylsiloxane composite improves the fire retardant property.

  20. The protective effect of hesperetin and nano-hesperetin on object recognition memory in animal model of Alzheimer

    Directory of Open Access Journals (Sweden)

    2017-11-01

    Full Text Available Background and objectives: Hesperetin (Hst, aglycone form of hesperidin, is reported to have antioxidant, anti-inflammatory and neuroprotective activities. On the other hand, the latest nanoparticle technology can help to improve the bioavailability of Hst, which is affected by the final particle size and stability. Alzheimer’s disease is a neurodegenerative disease, characterized by loss of the cognitive abilities, including memory, speech, emotions, and personality. Oxidative stress, a condition that occurs due to the imbalance in oxidant and antioxidant status, has been known to play a vital role in the pathophysiology of neurodegenerative diseases. This study was carried out in order to evaluate the protective effects of hesperetin and nano-hesperetin on memory disorder in the brains of Alzheimer’s animal models. Methods: Forty nine male rats were divided into 7 groups: control, vehicle, STZ group (rats were injected with STZ, treatment groups receiving 10 and 20 mg/kg/day of hesperetin and nano-hesperetin. Then 3 μgr/rat of (STZ was injected to the cerebroventricular of rats of all groups except the control and vehicle groups. The 4 treatment groups were gavaged by, respectively 10, 20 mg/Kg of hesperetin and nano-hesperetin for 30 days. After three weeks, recognition memory was examined by novel object recognition test. Results: The results showed that injection of STZ increased memory disorders (p≤0.001 and treatment of hesperetin and nano-hesperetin effectively decreased memory disorders (p

  1. Applications of Nano palm oil fuel ash and Nano fly ash in concrete

    Science.gov (United States)

    Hamada, Hussein M.; Jokhio, Gul Ahmed; Mat Yahaya, Fadzil; Humada, Ali M.

    2018-04-01

    This paper discusses the applications of Nano waste materials including palm oil fuel ash and fly ash in the concrete production. The implementation of nanotechnology has been instrumental in the development of significant interest among the stakeholders to improve the mechanical and chemical properties of materials involved in the production of concrete. Although many researchers have shown the potential of nanomaterials to increase strength and durability of concrete and improve its physical and chemical properties, there is still a knowledge gap regarding the preparation of Nano waste materials from agricultural waste to use as cement replacement instead of non-renewable materials. Therefore, it should be focused on to study Nano- waste materials to benefit from these characteristics during preparation of concrete mixtures. Therefore, this paper highlights the potential of waste materials in the Nano size to partially replace cement in concrete and achieve the same or better result than the traditional concrete. This paper recommends to conduct further experimental works to improve the concrete material properties by investigating the properties of waste materials in Nano size.

  2. Nano Ag-Doped In2O3 Thick Film: A Low-Temperature H2S Gas Sensor

    Directory of Open Access Journals (Sweden)

    D. N. Chavan

    2011-01-01

    Full Text Available Thick films of AR grade In2O3 were prepared by standard screen-printing technique. The gas sensing performances of thick films were tested for various gases. It showed maximum sensitivity to ethanol vapour at 350°C for 80 ppm concentration. To improve the sensitivity and selectivity of the film towards a particular gas, In2O3 sensors were surface-modified by dipping them in a solution of 2% nanosilver for different intervals of time. Obtained results indicated that spherical nano-Ag grains are highly dispersed on the surface of In2O3sensor. The surface area of the nano-Ag/ In2O3 sensor is several times larger than that of pure In2O3 sensor. In comparison with pure In2O3 sensor, all of the nano-Ag-doped sensors showed better sensing performance in respect of response, selectivity, and optimum operating temperature. The surface-modified (30 min In2O3 sensor showed larger sensitivity to H2S gas (10 ppm at 100°C. Nano silver on the surface of the film shifts the reactivity of film from ethanol vapour to H2S gas. A systematic study of gas sensing performance of the sensor indicates the key role played by the nano silver species on the surface. The sensitivity, selectivity, response, and recovery time of the sensor were measured and presented.

  3. Equilibrium isotherms, kinetics, and thermodynamics studies for congo red adsorption using calcium alginate beads impregnated with nano-goethite.

    Science.gov (United States)

    Munagapati, Venkata Subbaiah; Kim, Dong-Su

    2017-07-01

    The present study is concerned with the batch adsorption of congo red (CR) from an aqueous solution using calcium alginate beads impregnated with nano-goethite (CABI nano-goethite) as an adsorbent. The optimum conditions for CR removal were determined by studying operational variables viz. pH, adsorbent dose, contact time, initial dye ion concentration and temperature. The CABI nano-goethite was characterized by Fourier transform infrared spectroscopy (FTIR), X- ray diffraction (XRD) and Scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) analysis. The CR sorption data onto CABI nano-goethite were described using Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherm models. The results show that the best fit was achieved with the Langmuir isotherm model. The maximum adsorption capacity (181.1mg/g) of CR was occurred at pH 3.0. Kinetic studies showed that the adsorption followed a pseudo-second-order model. Desorption experiments were carried out to explore the feasibility of regenerating the adsorbent and the adsorbed CR from CABI nano-goethite. The best desorbing agent was 0.1M NaOH with an efficiency of 94% recovery. The thermodynamic parameters ΔG°, ΔH°, and ΔS° for the CR adsorption were determined by using adsorption capacities at five different temperatures (293, 303, 313, 323 and 303K). Results show that the adsorption process was endothermic and favoured at high temperature. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Bioinspiration From Nano to Micro Scales

    CERN Document Server

    2012-01-01

    Methods in bioinspiration and biomimicking have been around for a long time. However, due to current advances in modern physical, biological sciences, and technologies, our understanding of the methods have evolved to a new level. This is due not only to the identification of mysterious and fascinating phenomena but also to the understandings of the correlation between the structural factors and the performance based on the latest theoretical, modeling, and experimental technologies. Bioinspiration: From Nano to Micro Scale provides readers with a broad view of the frontiers of research in the area of bioinspiration from the nano to macroscopic scales, particularly in the areas of biomineralization, antifreeze protein, and antifreeze effect. It also covers such methods as the lotus effect and superhydrophobicity, structural colors in animal kingdom and beyond, as well as behavior in ion channels. A number of international experts in related fields have contributed to this book, which offers a comprehensive an...

  5. Thermoelectric properties of silicon nano pillars

    Energy Technology Data Exchange (ETDEWEB)

    Stranz, Andrej; Soekmen, Uensal; Waag, Andreas; Peiner, Erwin [Institute of Semiconductor Technology, Braunschweig (Germany)

    2010-07-01

    In order to establish silicon as a efficient thermoelectric material, its high thermal conductivity has to be reduced which is feasible, e.g., by nano structuring. Therefore, in this study Si-based sub-micron pillars of various dimensions were investigated. Using anisotropic etching followed by thermal oxidation we could fabricate pillars of diameters <500 nm, about 25 {mu}m in height with aspect ratios of more than 50. The distance between the pillars was varied from 500 nm to 10 micron. Besides the fabrication and structural characterization of sub-micron silicon pillars, and adequate metrology for measuring their thermoelectric properties was implemented. Commercial tungsten probes and self-made gold probes, as well as Wollaston wire probes were used for electrical and thermal conductivity, as well as Seebeck voltage measurements on single pillars in a scanning electron microscope equipped with nano manipulators.

  6. Dynamics of magnetic nano-particle assembly

    International Nuclear Information System (INIS)

    Kondratyev, V N

    2010-01-01

    Ferromagnetically coupled nano-particle assembly is analyzed accounting for inter- and intra- particle electronic structures within the randomly jumping interacting moments model including quantum fluctuations due to the discrete levels and disorder. At the magnetic jump anomalies caused by quantization the magnetic state equation and phase diagram are found to indicate an existence of spinodal regions and critical points. Arrays of magnetized nano-particles with multiple magnetic response anomalies are predicted to display some specific features. In a case of weak coupling such arrays exhibit the well-separated instability regions surrounding the anomaly positions. With increasing coupling we observe further structure modification, plausibly, of bifurcation type. At strong coupling the dynamical instability region become wide while the stable regime arises as a narrow islands at small disorders. It is shown that exploring correlations of magnetic noise amplitudes represents convenient analytical tool for quantitative definition, description and study of supermagnetism, as well as self-organized criticality.

  7. Nano-photonics: past and present

    Science.gov (United States)

    Szu, Harold

    2010-04-01

    Nanotech is at the scale of 10-9 meters, located at the mesocopic transition phase, which can take both classical mechanics (CM) and quantum mechanics (QM) descriptions bridging ten orders of magnitude phenomena, between the microscopic world of a single atom at 10-10 meters with the macroscopic world at meters. However, QM principles aid the understanding of any unusual property at the nanotech level. The other major difference between nano-photonics and other forms of optics is that the nano-scale is not very 'hands on'. For the most part, we will not be able to see the components with our naked eyes, but will be required to use some nanotech imaging tools, as follows:

  8. Manufacture of Nano Structures in Polymer Material

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Pedersen, H.C.; Staun, Jacob

    2003-01-01

    The incorporation of micro and nano technology into the products of the future is an area of increasing interest. The ideas for new products based on this technology often take their starting point in specific scientific fields whereas the subsequent design and product development not necessarily...... is based on a systematic approach including manufacturing processes and production system capabilities. The process chain associated with micro and nano injection moulding usually comprises silicon or photoresist mastering, electroforming and polymer processing. Additionally, if the produced polymer...... components are to be used in a microsystem, subsequent handling and assembly is necessary. The present paper describes the process chain related to the manufacture of optical gratings with nanometer-sized structures. The problems of each process step and the challenges of establishing a coherent production...

  9. Heat Conduction of Air in Nano Spacing

    Directory of Open Access Journals (Sweden)

    Zhang Yao-Zhong

    2009-01-01

    Full Text Available Abstract The scale effect of heat conduction of air in nano spacing (NS is very important for nanodevices to improve their life and efficiency. By constructing a special technique, the changes of heat conduction of air were studied by means of measuring the heat conduction with heat conduction instrument in NS between the hot plate and the cooling plate. Carbon nanotubes were used to produce the nano spacing. The results show that when the spacing is small down to nanometer scale, heat conduction plays a prominent role in NS. It was found that the thickness of air is a non-linear parameter for demarcating the heat conduction of air in NS and the rate of heat conduction in unit area could be regard as a typical parameter for the heat conduction characterization at nanometer scale.

  10. Nano silicon for lithium-ion batteries

    International Nuclear Information System (INIS)

    Holzapfel, Michael; Buqa, Hilmi; Hardwick, Laurence J.; Hahn, Matthias; Wuersig, Andreas; Scheifele, Werner; Novak, Petr; Koetz, Ruediger; Veit, Claudia; Petrat, Frank-Martin

    2006-01-01

    New results for two types of nano-size silicon, prepared via thermal vapour deposition either with or without a graphite substrate are presented. Their superior reversible charge capacity and cycle life as negative electrode material for lithium-ion batteries have already been shown in previous work. Here the lithiation reaction of the materials is investigated more closely via different electrochemical in situ techniques: Raman spectroscopy, dilatometry and differential electrochemical mass spectrometry (DEMS). The Si/graphite compound material shows relatively high kinetics upon discharge. The moderate relative volume change and low gas evolution of the nano silicon based electrode, both being important points for a possible future use in real batteries, are discussed with respect to a standard graphite electrode

  11. Effect of TMAH Etching Duration on the Formation of Silicon Nano wire Transistor Patterned by AFM Nano lithography

    International Nuclear Information System (INIS)

    Hutagalung, S.D.; Lew, K.C.

    2012-01-01

    Atomic force microscopy (AFM) lithography was applied to produce nano scale pattern for silicon nano wire transistor fabrication. This technique takes advantage of imaging facility of AFM and the ability of probe movement controlling over the sample surface to create nano patterns. A conductive AFM tip was used to grow the silicon oxide nano patterns on silicon on insulator (SOI) wafer. The applied tip-sample voltage and writing speed were well controlled in order to form pre-designed silicon oxide nano wire transistor structures. The effect of tetra methyl ammonium hydroxide (TMAH) etching duration on the oxide covered silicon nano wire transistor structure has been investigated. A completed silicon nano wire transistor was obtained by removing the oxide layer via hydrofluoric acid etching process. The fabricated silicon nano wire transistor consists of a silicon nano wire that acts as a channel with source and drain pads. A lateral gate pad with a nano wire head was fabricated very close to the channel in the formation of transistor structures. (author)

  12. Effects of incorporation of nano-fluorapatite or nano-fluorohydroxyapatite on a resin-modified glass ionomer cement.

    Science.gov (United States)

    Lin, Jun; Zhu, Jiajun; Gu, Xiaoxia; Wen, Wenjian; Li, Qingshan; Fischer-Brandies, Helge; Wang, Huiming; Mehl, Christian

    2011-03-01

    This study aimed to investigate the fluoride release properties and the effect on bond strength of two experimental adhesive cements. Synthesized particles of nano-fluorapatite (nano-FA) or nano-fluorohydroxyapatite (nano-FHA) were incorporated into a resin-modified glass ionomer cement (Fuji Ortho LC) and characterized using X-ray diffraction and scanning electron microscopy. Blocks with six different concentrations of nano-FA or nano-FHA were manufactured and their fluoride release properties evaluated by ultraviolet spectrophotometry. The unaltered glass ionomer cement Fuji Ortho LC (GC, control) and the two experimental cements with the highest fluoride release capacities (nano-FA+Fuji Ortho LC (GFA) and nano-FHA+Fuji Ortho LC (GFHA)) were used to bond composite blocks and orthodontic brackets to human enamel. After 24 h water storage all specimens were debonded, measuring the micro-tensile bond strength (μTBS) and the shear bond strength (SBS), respectively. The optimal concentration of added nano-FA and nano-FHA for maximum fluoride release was 25 wt.%, which nearly tripled fluoride release after 70 days compared with the control group. GC exhibited a significantly higher SBS than GFHA/GFA, with GFHA and GFA not differing significantly (P>0.05). The μTBS of GC and GFA were significantly higher than that of GFHA (P≤0.05). The results seem to indicate that the fluoride release properties of Fuji Ortho LC are improved by incorporating nano-FA or nano-FHA, simultaneously maintaining a clinically sufficient bond strength when nano-FA was added. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  13. Multifunctional magnetic nano/microparticles for bioapplications

    Czech Academy of Sciences Publication Activity Database

    Horák, Daniel; Babič, Michal; Jendelová, Pavla; Herynek, V.

    2010-01-01

    Roč. 26, č. 2 (2010), s. 38 ISSN 0233-7657. [Bridges in Life Sciences, Annual Scientific Meeting Regional Cooperation for Health, Science and Technology /5./. 09.04.2010-11.04.2010, Lviv] R&D Projects: GA MŠk 2B06053 Institutional research plan: CEZ:AV0Z40500505 Keywords : magnetic * nano particle * microsphere Subject RIV: EE - Microbiology, Virology

  14. Method for producing nano-embedded microparticles

    DEFF Research Database (Denmark)

    2015-01-01

    of the invention. (FR)La présente invention concerne un procédé rapide, à haut rendement et continu de production de nano-microparticules intégrées sous forme de poudre, ce qui permet d'obtenir un procédé économique qui peut être mis en oeuvre de manière aseptique. L'invention concerne, en outre, un appareil pour...

  15. Asphaltenes-based polymer nano-composites

    Science.gov (United States)

    Bowen, III, Daniel E

    2013-12-17

    Inventive composite materials are provided. The composite is preferably a nano-composite, and comprises an asphaltene, or a mixture of asphaltenes, blended with a polymer. The polymer can be any polymer in need of altered properties, including those selected from the group consisting of epoxies, acrylics, urethanes, silicones, cyanoacrylates, vulcanized rubber, phenol-formaldehyde, melamine-formaldehyde, urea-formaldehyde, imides, esters, cyanate esters, allyl resins.

  16. The Next Technology Revolution - Nano Electronic Technology

    Science.gov (United States)

    Turlik, Iwona

    2004-03-01

    Nanotechnology is a revolutionary engine that will engender enormous changes in a vast majority of today's industries and markets, while potentially creating whole new industries. The impact of nanotechnology is particularly significant in the electronics industry, which is constantly driven by the need for higher performance, increased functionality, smaller size and lower cost. Nanotechnology can influence many of the hundreds of components that are typically assembled to manufacture modern electronic devices. Motorola manufactures electronics for a wide range of industries and communication products. In this presentation, the typical components of a cellular phone are outlined and technology requirements for future products, the customer benefits, and the potential impact of nanotechnology on many of the components are discussed. Technology needs include reliable materials supply, processes for high volume production, experimental and simulation tools, etc. For example, even routine procedures such as failure characterization may require the development of new tools for investigating nano-scale phenomena. Business needs include the development of an effective, high volume supply chain for nano-materials and devices, disruptive product platforms, and visible performance impact on the end consumer. An equally significant long-term industry need is the availability of science and engineering graduates with a multidisciplinary focus and a deep understanding of the fundamentals of nano-technology, that can harness the technology to create revolutionary products.

  17. Computer simulations for the nano-scale

    International Nuclear Information System (INIS)

    Stich, I.

    2007-01-01

    A review of methods for computations for the nano-scale is presented. The paper should provide a convenient starting point into computations for the nano-scale as well as a more in depth presentation for those already working in the field of atomic/molecular-scale modeling. The argument is divided in chapters covering the methods for description of the (i) electrons, (ii) ions, and (iii) techniques for efficient solving of the underlying equations. A fairly broad view is taken covering the Hartree-Fock approximation, density functional techniques and quantum Monte-Carlo techniques for electrons. The customary quantum chemistry methods, such as post Hartree-Fock techniques, are only briefly mentioned. Description of both classical and quantum ions is presented. The techniques cover Ehrenfest, Born-Oppenheimer, and Car-Parrinello dynamics. The strong and weak points of both principal and technical nature are analyzed. In the second part we introduce a number of applications to demonstrate the different approximations and techniques introduced in the first part. They cover a wide range of applications such as non-simple liquids, surfaces, molecule-surface interactions, applications in nano technology, etc. These more in depth presentations, while certainly not exhaustive, should provide information on technical aspects of the simulations, typical parameters used, and ways of analysis of the huge amounts of data generated in these large-scale supercomputer simulations. (author)

  18. Gold nano-particles fixed on glass

    International Nuclear Information System (INIS)

    Worsch, Christian; Wisniewski, Wolfgang; Kracker, Michael; Rüssel, Christian

    2012-01-01

    Highlights: ► We produced wear resistant gold–ruby coatings on amorphous substrates. ► Thin sputtered gold layers were covered by or embedded in silica coatings. ► Annealing above T g of the substrate glass led to the formation of gold nano particles. ► A 1 1 1-texture of the gold particles is observed via XRD and EBSD. ► EBSD-patterns can be acquired from crystals covered by a thin layer of glass. - Abstract: A simple process for producing wear resistant gold nano-particle coatings on transparent substrates is proposed. Soda-lime-silica glasses were sputtered with gold and subsequently coated with SiO 2 using a combustion chemical vapor deposition technique. Some samples were first coated with silica, sputtered with gold and then coated with a second layer of silica. The samples were annealed for 20 min at either 550 or 600 °C. This resulted in the formation of round, well separated gold nano-particles with sizes from 15 to 200 nm. The color of the coated glass was equivalent to that of gold–ruby glasses. Silica/gold/silica coatings annealed at 600 °C for 20 min were strongly adherent and scratch resistant. X-ray diffraction and electron backscatter diffraction (EBSD) were used to describe the crystal orientations of the embedded particles. The gold particles are preferably oriented with their (1 1 1) planes perpendicular to the surface.

  19. Nano-education from a European perspective

    International Nuclear Information System (INIS)

    Malsch, I

    2008-01-01

    At a global level, educating the nanotechnology workforce has been discussed since the beginning of the new millennium. Scientists, engineers and technicians should be trained in nanotechnology. Most educators prefer training students first in their own discipline at the Bachelor level (physics, chemistry, biology, etc) followed by specialisation in nanoscience and technology at the Master's level. Some favour a broad interdisciplinary basic training in different nanosciences followed by specialisation in a particular application area. What constitutes a good nanoscience curriculum is also being discussed, as well as the application of e-learning methodologies. The European Union is stimulating the development of nanoscience education in universities. The Erasmus Mundus programme is funding nanoscience and nanotechnology education programmes involving universities in several European countries. The policy debate in Europe is moving towards vocational training in nanotechnology for educating the technicians needed in industry and research. The EU vocational training institute CEDEFOP published a report in 2005 The EU funded European gateway to nanotechnology Nanoforum has stimulated the accessibility of nano-education throughout Europe with reports and online databases of education courses and materials. For university education, they list courses at the Bachelor, Master's, and PhD level as well as short courses. The EU funded EuroIndiaNet project also reviewed Nano-education courses at the Master's level, short courses, e-learning programmes, summerschools and vocational training courses. In this presentation, I review Nanoforum and other publications on nano-education in Europe and highlight current trends and gaps

  20. Magnetite nano-islands on Graphene

    Science.gov (United States)

    Anderson, Nathaniel; Zhang, Qiang; Rosenberg, Richard; Vaknin, David

    X-ray magnetic circular dichroism (XMCD) of ex-situ iron nano-islands grown on graphene reveals that iron oxidation spontaneously leads to the formation of magnetite nano-particles - i.e, the formation of the inverse spinel Fe3O4. Fe islands have been grown with two different heights (20 and 75 MLs) on epitaxial graphene and we have determined their magnetic behavior both as function of temperature and applied external field. Our XAS and XMCD at an applied magnetic field of B = 5 T show that the thin film (20 MLs) is totally converted to magnetite whereas the thicker film (75 MLs) exhibits magnetite properties but also those of pure metal iron. For both samples, temperature dependence of the XMCD shows clear transitions at ~120 K consistent with the Verwey transition of bulk magnetite. XMCD at low temperatures shows a weak hysteresis and provide the average spin and angular-momentum moments, the dipolar term, and the total moment . In addition, manipulation and comparison of the XMCD data from both samples allows us to extract information about the pure iron nano-islands from the thicker sample. Ames Laboratory is supported by the U.S. DOE, BES, MSE Contract No. DE-AC02-07CH11358. APS is supported by U.S. DOE Contract No. DE-AC02-06CH11357.

  1. Development of nano-roughness calibration standards

    International Nuclear Information System (INIS)

    Baršić, Gorana; Mahović, Sanjin; Zorc, Hrvoje

    2012-01-01

    At the Laboratory for Precise Measurements of Length, currently the Croatian National Laboratory for Length, unique nano-roughness calibration standards were developed, which have been physically implemented in cooperation with the company MikroMasch Trading OU and the Ruđer Bošković Institute. In this paper, a new design for a calibration standard with two measuring surfaces is presented. One of the surfaces is for the reproduction of roughness parameters, while the other is for the traceability of length units below 50 nm. The nominal values of the groove depths on these measuring surfaces are the same. Thus, a link between the measuring surfaces has been ensured, which makes these standards unique. Furthermore, the calibration standards available on the market are generally designed specifically for individual groups of measuring instrumentation, such as interferometric microscopes, stylus instruments, scanning electron microscopes (SEM) or scanning probe microscopes. In this paper, a new design for nano-roughness standards has been proposed for use in the calibration of optical instruments, as well as for stylus instruments, SEM, atomic force microscopes and scanning tunneling microscopes. Therefore, the development of these new nano-roughness calibration standards greatly contributes to the reproducibility of the results of groove depth measurement as well as the 2D and 3D roughness parameters obtained by various measuring methods. (paper)

  2. Titanium oxide (TiO{sub 2}) nanoparticles in induction of apoptosis and inflammatory response in brain

    Energy Technology Data Exchange (ETDEWEB)

    Meena, Ramovatar, E-mail: rammeenarv@gmail.com; Kumar, Sumit; Paulraj, R., E-mail: paulrajr@hotmail.com [Jawaharlal Nehru University, School of Environmental Sciences (India)

    2015-01-15

    The ever increasing applications of engineered nanoparticles in 21st century cause serious concern about its potential health risks on living being. Regulatory health risk assessment of such particles has become mandatory for the safe use of nanomaterials in consumer products and medicines. In order to study the mechanism underlying the effects of nano-TiO{sub 2} (TiO{sub 2} nanoparticles) on the brain, wistar rats were administrated intravenously with various doses of nano-TiO{sub 2} (21 nm) through the caudal vein, once a week for 4 weeks and different parameters such as bioaccumulation of nano-TiO{sub 2}, oxidative stress-mediated response, level of inflammatory markers such as NF-κB (p65), HSP 60, p38, nitric oxide, IFN-γ and TNF-α, and level of neurochemicals in brain as well as DNA damage and expression of apoptosis markers (p53, Bax, Bcl-2, and cyto c) were evaluated. Results show that the concentration of nano-TiO{sub 2} in the brain increased with increasing the doses of nano-TiO{sub 2}. Oxidative stress and injury of the brain occurred as nano-TiO{sub 2} appeared to trigger a cascade of reactions such as inflammation, lipid peroxidation, decreases the activities of antioxidative enzymes and melatonin level, the reduction of glutamic acid, downregulated levels of acetylcholinesterase activities, and the increase in caspase-3 activity (a biomarker of apoptosis), DNA fragmentation, and apoptosis. It may be concluded that nano-TiO{sub 2} induces oxidative stress that leads to activation of inflammatory cytokines and an alteration in the level of neurotransmitters resulted in the induction of mitochondrial-mediated apoptosis.

  3. Extraction and characterization of cellulose nano whiskers from balsa wood

    International Nuclear Information System (INIS)

    Morelli, Carolina L.; Bretas, Rosario E.S.; Marconcini, Jose M.; Pereira, Fabiano V.; Branciforti, Marcia C.

    2011-01-01

    In this study cellulose nano whiskers were obtained from balsa wood. For this purpose, fibers of balsa wood were subjected to hydrolysis reactions for lignin and hemi cellulose digestion and acquisition of nano-scale cellulose. Cellulose nano crystals obtained had medium length and thickness of 176 nm and 7 nm respectively. Infrared spectroscopy and x-ray diffraction showed that the process used for extracting nano whiskers could digest nearly all the lignin and hemi cellulose from the balsa fiber and still preserve the aspect ratio and crystallinity, satisfactory enough for future application in polymer nano composites. Thermogravimetry showed that the onset temperature of thermal degradation of cellulose nano crystals (226 degree C) was higher than the temperature of the balsa fiber (215 degree C), allowing its use in molding processes with many polymers from the molten state.(author)

  4. Drug Delivery Systems: A New Frontier in Nano-technology

    Directory of Open Access Journals (Sweden)

    Chamindri Witharana

    2017-09-01

    Full Text Available Nano-technology is a recent advancement in science, defined as “Science, engineering, and technology conducted at the Nano scale” (National nanotechnology initiatives in USA. Applications of Nano-technology cover a vast range from basic material science, personal care applications, agriculture, and medicine. Nano-technology is used in field of medicine for treatment, diagnostic, monitoring, genetic engineering, and drug delivery. There are two main types of Nano Particles (NPs used in drug delivery; organic NPs and inorganic NPs. In drug delivery, the drug-Nano- Particle (NP conjugate should be able to deliver drugs to the target site without degradation in gastrointestinal track and without reducing drug activity. Further, it should attack to target cells without causing any adverse effects. The ultimate goal of NP drug delivery is to improve proper treatment, effectiveness, less side effects with safety and patient adherence as well as reduction in the cost.

  5. Optical and Structural Characterizations of GaN Nano structures

    International Nuclear Information System (INIS)

    Shekari, L.; Abu Hassan, H.; Thahab, S.M.

    2011-01-01

    We have grown wurtzite GaN nano wires (NWs) on polished silicon (Si) either with or without Au as catalyst, using commercial GaN powder by thermal evaporation in an atmosphere of argon (Ar) gas. Structural and optical characterizations were performed using high resolution X-ray diffraction (HR-XRD), scanning electron microscopy (SEM), photoluminescence (PL) and energy-dispersive X-ray spectroscopy (EDX) spectroscopy. Results indicate that the nano wires are of single-crystal hexagonal GaN and the nano wires on Si with Au catalyst are more oriented than those without Au catalyst; and using catalyst make the NWs grow much faster and quite well-ordered. The compositional quality of the grown nano wires on the substrates are mostly same, however the nano wires on the Au coated silicon are of low density, while the nano wires on the Si are of high density. (author)

  6. Toughening by nano-scaled twin boundaries in nanocrystals

    International Nuclear Information System (INIS)

    Zhou, Haofei; Qu, Shaoxing; Yang, Wei

    2010-01-01

    Joint enhancement on strength and toughness provides a cutting-edge research frontier for metals and alloys. Conventional strengthening methods typically lead to suppressed ductility and fracture toughness. In this study, large-scale atomic simulation on the fracture process is performed featuring nanocrystals embedded with nano-scaled twin boundaries (TBs). Four toughening mechanisms by nano-scaled TBs are identified: (i) crack blunting through dislocation accommodation along the nano-scaled TBs; (ii) crack deflection in a manner of intragranular propagation; (iii) daughter crack formation along the nano-scaled TBs that further enhances the toughness and (iv) curved TB planes owing to an excessive pileup of geometrically necessary dislocations. These toughening mechanisms jointly dictate the mechanical behavior of nano-structured materials, and provide insights into the application of nano-scaled TBs with an aim to simultaneously obtain enhanced strength and toughness. New approaches to introduce these coherent internal defects into the nanostructure of crystalline materials are also proposed

  7. Micro/nano-fabrication technologies for cell biology.

    Science.gov (United States)

    Qian, Tongcheng; Wang, Yingxiao

    2010-10-01

    Micro/nano-fabrication techniques, such as soft lithography and electrospinning, have been well-developed and widely applied in many research fields in the past decade. Due to the low costs and simple procedures, these techniques have become important and popular for biological studies. In this review, we focus on the studies integrating micro/nano-fabrication work to elucidate the molecular mechanism of signaling transduction in cell biology. We first describe different micro/nano-fabrication technologies, including techniques generating three-dimensional scaffolds for tissue engineering. We then introduce the application of these technologies in manipulating the physical or chemical micro/nano-environment to regulate the cellular behavior and response, such as cell life and death, differentiation, proliferation, and cell migration. Recent advancement in integrating the micro/nano-technologies and live cell imaging are also discussed. Finally, potential schemes in cell biology involving micro/nano-fabrication technologies are proposed to provide perspectives on the future research activities.

  8. Core-shell architectures as nano-size transporters

    International Nuclear Information System (INIS)

    Adeli, M.; Zarnegar, Z.; Kabiri, R.; Salimi, F.; Dadkah, A.

    2006-01-01

    Core-shell architectures containing poly (ethylene imine) (PEI) as a core and poly (lactide) (PLA) as arms were prepared. PEI was used as macro initiator for ring opening polymerization of lactide. PEI-PLA core-shell architectures were able to encapsulate guest molecules. Size of the core-shell architectures was between 10- 100 nm, hence they can be considered as nano carriers to transport the guest molecules. Transport capacity of nano carriers depends on their nano-environments and type of self-assembly in solvent. In solid state nano carriers self-assemble as long structures with nano-size diameter or they form network structures. Aggregations type depends on the concentration of nano carriers in solution. Effect of the shell thickness and aggregation type on the release rate are also investigated

  9. Conductive nano composites based on cellulose nano fiber coated poly aniline via in situ polymerization

    International Nuclear Information System (INIS)

    Silva, Michael J. da; Sanches, Alex O.; Malmonge, Luiz F.; Malmonge, Jose A.; Medeiros, Eliton S. de; Rosa, Morsyleide F.

    2011-01-01

    Cellulose nano fiber (CNF) was extracted by acid hydrolysis from cotton microfibril and nano composites of CNF/PANI-DBSA were obtained by in situ polymerization of aniline onto CNF. The ratios between DBSA/aniline and aniline/oxidant were varied and the nano composites were characterized by four probes direct current (dc) electrical conductivity, ultraviolet-visible (UV-Vis-NIR) and FTIR spectroscopy and X-ray diffraction (XRD). Electrical conductive about ∼10 -1 S/cm was research and was independent of DBSA/aniline molar ratio between 2-4 and the aniline/oxidant molar ratio between 1-5. X-ray patterns of the samples show crystalline peaks characteristic of cellulose I. The FTIR spectra confirmed the presence of PANI and CNF in all samples. (author)

  10. Linear electrostatic micromotors for nano- and micro-positioning

    Science.gov (United States)

    Baginsky, I. L.; Kostsov, Edvard G.

    2004-05-01

    The functioning of the linear step electrostatic film micromotors with the short controlling pulse (less then 100-200 ´s) is studied to create nano- and micro-positioners. The theoretical study of the step movement of the given mass in this time frame is carried out. The results of the experimental studies of the multipetal reciprocal micromotors created on the basis of La modified Ba0.5Sr0.5Nb2O6 ferroelectric films with 1-3 μm thickness are shown. The petals were made of beryllium bronze. It is shown that the electrostatic rolling can last less than 50 μs, and the process of separating two surfaces (the metal and the ferroelectric) can last less than 1 μs. These parameters allow one to operate the micromotor at 1-10 kHz frequency, and the propulsion force in the beginning (the first 20-100 μs) of the electrostatic rolling can be as high as 1-10 N per 1 mm2 of the rolling surface with the voltage pulse amplitude of 40-50 V. The possibility of obtaining moving plate (MP) step in the nanometer range is studied, as well as the precision of these steps during the continuous MP movement with the different clock frequencies and durations of the voltage pulses. The recommendations are given to improve the accuracy and the speed of the positioning in the nano- and micro-movement range. Possible fields of micromotor application are micromechanics, including precision micromechanics, microelectronics, microrobots, microoptics, microscanners, micropumps (e.g. in the jet printers), micro flying vehicles etc.

  11. The Art of Photoelectron Spectroscopy, from Micro to Nano

    Science.gov (United States)

    Rotenberg, Eli

    Angle-resolved photoemission spectroscopy (ARPES) was developed for the determination of the electronic bandstructure of solids. In the last 20 years, ARPES has become nearly unlimited with respect to instrumental resolution, and therefore able to illuminate more subtle electronic aspects, such as ground-state symmetry breaking and the many-body interactions (MBIs) that characterize ground states such as superconductivity. These MBIs involve exchange of momentum among electrons or with excitations such as phonons, and can therefore couple to nanoscale structures. By controlling the structure at the nanoscale, we can therefore hope to control or enhance the ground state properties of materials through nanoscale engineering. This dream has motivated the development of nanoscale ARPES (nanoARPES) machines that are now coming online worldwide. After a brief overview, I will show the latest results from the new nanoARPES endstation at the MAESTRO facility (Microscopic and Electronic Structure Observatory), a new user beamline commissioned this year at the Advanced Light Source (ALS). We achieved routine operation at spatial resolution around 120 nm, and expect improvement down to 50 nm or better. Examples will include graphene and 2D-metal-chalcogenide heterostructures. I will also discuss the prospects for dramatic improvements expected as new diffraction-limited light sources such as the ALS-U project are realized. Work performed at the Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

  12. Advanced vectorial simulation of VCSELs with nano structures invited paper

    DEFF Research Database (Denmark)

    Chung, Il-Sug; Mørk, Jesper

    2009-01-01

    The single-mode properties and design issues of three vertical-cavity surface-emitting laser (VCSEL) structures incorporating nano structures are rigorously investigated. Nano structuring enables to deliver selective pumping or loss to the fundamental mode as well as stabilizing the output...... polarization state. Comparison of three vectorial simulation methods reveals that the modal expansion method is suitable for treating the nano structured VCSEL designs....

  13. Review on the Synthesis and Applications of Nano materials

    International Nuclear Information System (INIS)

    Liu, X.; Tang, Y.; Liang, B.; Zhong, Z.

    2013-01-01

    Recently, Fe 3 O 4 nano materials have attracted tremendous attention because of their favorable electric and magnetic properties. Fe 3 O 4 nano structures with various morphologies have been successfully synthesized and have been used in many fields such as lithium-ion batteries (LIBs), wastewater treatment, and magnetic resonance imaging (MRI) contrast agents. In this paper, we provide an in-depth discussion of recent development of Fe 3 O 4 nano materials, including their effective synthetic methods and potential applications.

  14. Ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory

    International Nuclear Information System (INIS)

    Han, Jinhua; Wang, Wei; Ying, Jun; Xie, Wenfa

    2014-01-01

    An ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory was demonstrated, with discrete distributed gold nanoparticles, tetratetracontane (TTC), pentacene as the floating-gate layer, tunneling layer, and active layer, respectively. The electron traps at the TTC/pentacene interface were significantly suppressed, which resulted in an ambipolar operation in present memory. As both electrons and holes were supplied in the channel and trapped in the floating-gate by programming/erasing operations, respectively, i.e., one type of charge carriers was used to overwrite the other, trapped, one, a large memory window, extending on both sides of the initial threshold voltage, was realized

  15. Ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jinhua; Wang, Wei, E-mail: wwei99@jlu.edu.cn; Ying, Jun; Xie, Wenfa [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012 (China)

    2014-01-06

    An ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory was demonstrated, with discrete distributed gold nanoparticles, tetratetracontane (TTC), pentacene as the floating-gate layer, tunneling layer, and active layer, respectively. The electron traps at the TTC/pentacene interface were significantly suppressed, which resulted in an ambipolar operation in present memory. As both electrons and holes were supplied in the channel and trapped in the floating-gate by programming/erasing operations, respectively, i.e., one type of charge carriers was used to overwrite the other, trapped, one, a large memory window, extending on both sides of the initial threshold voltage, was realized.

  16. [Biomimetic mineralization of rod-like cellulose nano-whiskers and spectrum analysis].

    Science.gov (United States)

    Qu, Ping; Wang, Xuan; Cui, Xiao-xia; Zhang, Li-ping

    2012-05-01

    Cellulose nano-whiskers/nano-hydroxyapatite composite was prepared with biomimetic mineralization using rod-like cellulose nano-whiskers as template. The cellulose nano-whiskers and cellulose nano-whiskers/nano-hydroxyapatite composite were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope-energy dispersive analysis of X-rays (SEM-EDXA). Variation and distribution of carbon, oxygen, calcium, and phosphorus in the composites were studied. The morphologies and growth mechanism of nano-hydroxyapatite were analyzed. The results showed that nano-hydroxyapatite was formed on the surface of cellulose nano-whiskers; the carbon-oxygen ratio of cellulose nano-whiskers and cellulose nano-whiskers/nano-hydroxyapatite composite was 1.81 and 1.54, respectively; the calcium-phosphorus ratio of the composite was 1.70. The nucleation of nano-hydroxyapatite was around the hydroxyl groups of cellulose nano-whiskers. It is suggested that there is coordination between the hydroxyl groups of cellulose nano-whiskers and calcium ions of nano-hydroxyapatite. The nano-hydroxyapatite can distribute in the matrix of cellulose nano-whiskers. From the atomic force microscope (AFM) images, we can see that the diameter of the spherical nano-hydroxyapatite particles was about 20 nm.

  17. Positron annihilation lifetime study of Nafion/titanium dioxide nano-composite membranes

    Science.gov (United States)

    Lei, M.; Wang, Y. J.; Liang, C.; Huang, K.; Ye, C. X.; Wang, W. J.; Jin, S. F.; Zhang, R.; Fan, D. Y.; Yang, H. J.; Wang, Y. G.

    2014-01-01

    Positron annihilation lifetime (PAL) technique is applied for investigation of size and number density of free volumes in Nafion/TiO2-nanoparticles composite membrane. The proton transporting ability is correlated with the properties of free volume inside the membrane. It is revealed that composite membrane with 5 wt% of TiO2 nano-fillers exhibits good electrochemical performance under reduced humidity and it can be saturated with water at relative humidity of 50%, under which ionic clusters and proton transporting channels are formed, indicating that composite membranes with 5 wt% of TiO2 nano-fillers are effective electrolyte for fuel cells operated at reduced humidification levels. The results suggest that PAL can be a powerful tool for elucidating the relationship between microstructure and ion transport in polymer electrolyte membranes.

  18. Demonstration of Ultra-Fast Switching in Nano metallic Resistive Switching Memory Devices

    International Nuclear Information System (INIS)

    Yang, Y.

    2016-01-01

    Interdependency of switching voltage and time creates a dilemma/obstacle for most resistive switching memories, which indicates low switching voltage and ultra-fast switching time cannot be simultaneously achieved. In this paper, an ultra-fast (sub-100 ns) yet low switching voltage resistive switching memory device (“nano metallic ReRAM”) was demonstrated. Experimental switching voltage is found independent of pulse width (intrinsic device property) when the pulse is long but shows abrupt time dependence (“cliff”) as pulse width approaches characteristic RC time of memory device (extrinsic device property). Both experiment and simulation show that the onset of cliff behavior is dependent on physical device size and parasitic resistance, which is expected to diminish as technology nodes shrink down. We believe this study provides solid evidence that nano metallic resistive switching memory can be reliably operated at low voltage and ultra-fast regime, thus beneficial to future memory technology.

  19. Investigations on a nano-scale periodical waveguide structure taking surface plasmon polaritons into consideration

    International Nuclear Information System (INIS)

    Liu Weihao; Zhong Renbin; Zhou Jun; Zhang Yaxin; Hu Min; Liu Shenggang

    2012-01-01

    Detailed theoretical analysis and computer simulations on the electromagnetic characteristics of a nano-scale periodical waveguide structure, taking surface plasmon polaritons (SPPs) into consideration, are carried out in this paper. The results show that SPPs will significantly influence the electromagnetic characteristics of the structure. When the operation frequency is in a certain band—the ‘radial confinement band’, neither radial surface plasmon waves nor guided waves, which both will lead to radial energy loss, can be excited in the structure. And the electromagnetic waves are completely confined within the longitudinal waveguide and propagate along it with little attenuation. The radial energy loss is then significantly reduced. These results are of great significance not only for increasing the efficiency of the radiation sources based on the nano-scale periodical waveguide structure but also for the development of high-efficiency waveguides and wide-band filters in the infrared and visible light regimes. (paper)

  20. Design and finite element method analysis of laterally actuated multi-value nano electromechanical switches

    KAUST Repository

    Kloub, Hussam; Smith, Casey; Hussain, Muhammad Mustafa

    2011-01-01

    We report on the design and modeling of novel nano electromechanical switches suitable for implementing reset/set flip-flops, AND, NOR, and XNOR Boolean functions. Multiple logic operations can be implemented using only one switching action enabling parallel data processing; a feature that renders this design competitive with complementary metal oxide semiconductor and superior to conventional nano-electromechanical switches in terms of functionality per device footprint. The structural architecture of the newly designed switch consists of a pinned flexural beam structure which allows low strain lateral actuation for enhanced mechanical integrity. Reliable control of on-state electrical current density is achieved through the use of metal-metal contacts, true parallel beam deflection, and lithographically defined contact area to prevent possible device welding. Dynamic response as a function of device dimensions numerically investigated using ANSYS and MatLab Simulink. © 2011 The Japan Society of Applied Physics.

  1. High Performance Nano-Crystalline Oxide Fuel Cell Materials. Defects, Structures, Interfaces, Transport, and Electrochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, Scott [Northwestern Univ., Evanston, IL (United States); Poeppelmeier, Ken [Northwestern Univ., Evanston, IL (United States); Mason, Tom [Northwestern Univ., Evanston, IL (United States); Marks, Lawrence [Northwestern Univ., Evanston, IL (United States); Voorhees, Peter [Northwestern Univ., Evanston, IL (United States)

    2016-09-07

    This project addresses fundamental materials challenges in solid oxide electrochemical cells, devices that have a broad range of important energy applications. Although nano-scale mixed ionically and electronically conducting (MIEC) materials provide an important opportunity to improve performance and reduce device operating temperature, durability issues threaten to limit their utility and have remained largely unexplored. Our work has focused on both (1) understanding the fundamental processes related to oxygen transport and surface-vapor reactions in nano-scale MIEC materials, and (2) determining and understanding the key factors that control their long-term stability. Furthermore, materials stability has been explored under the “extreme” conditions encountered in many solid oxide cell applications, i.e, very high or very low effective oxygen pressures, and high current density.

  2. Design and finite element method analysis of laterally actuated multi-value nano electromechanical switches

    KAUST Repository

    Kloub, Hussam

    2011-09-01

    We report on the design and modeling of novel nano electromechanical switches suitable for implementing reset/set flip-flops, AND, NOR, and XNOR Boolean functions. Multiple logic operations can be implemented using only one switching action enabling parallel data processing; a feature that renders this design competitive with complementary metal oxide semiconductor and superior to conventional nano-electromechanical switches in terms of functionality per device footprint. The structural architecture of the newly designed switch consists of a pinned flexural beam structure which allows low strain lateral actuation for enhanced mechanical integrity. Reliable control of on-state electrical current density is achieved through the use of metal-metal contacts, true parallel beam deflection, and lithographically defined contact area to prevent possible device welding. Dynamic response as a function of device dimensions numerically investigated using ANSYS and MatLab Simulink. © 2011 The Japan Society of Applied Physics.

  3. Recent Development of Nano-Materials Used in DNA Biosensors

    Directory of Open Access Journals (Sweden)

    Yibin Ying

    2009-07-01

    Full Text Available As knowledge of the structure and function of nucleic acid molecules has increased, sequence-specific DNA detection has gained increased importance. DNA biosensors based on nucleic acid hybridization have been actively developed because of their specificity, speed, portability, and low cost. Recently, there has been considerable interest in using nano-materials for DNA biosensors. Because of their high surface-to-volume ratios and excellent biological compatibilities, nano-materials could be used to increase the amount of DNA immobilization; moreover, DNA bound to nano-materials can maintain its biological activity. Alternatively, signal amplification by labeling a targeted analyte with nano-materials has also been reported for DNA biosensors in many papers. This review summarizes the applications of various nano-materials for DNA biosensors during past five years. We found that nano-materials of small sizes were advantageous as substrates for DNA attachment or as labels for signal amplification; and use of two or more types of nano-materials in the biosensors could improve their overall quality and to overcome the deficiencies of the individual nano-components. Most current DNA biosensors require the use of polymerase chain reaction (PCR in their protocols. However, further development of nano-materials with smaller size and/or with improved biological and chemical properties would substantially enhance the accuracy, selectivity and sensitivity of DNA biosensors. Thus, DNA biosensors without PCR amplification may become a reality in the foreseeable future.

  4. Nano-funnels as electro-osmotic ``tweezers and pistons''

    Science.gov (United States)

    Wang, Yanqian; Panyukov, Sergey; Zhou, Jinsheng; Menard, Laurent D.; Ramsey, J. Michael; Rubinstien, Michael

    2014-03-01

    An electric field is used to force a DNA molecule into a nano-channel by compensating the free energy penalty that results from the reduced conformational entropy of the confined macromolecule. Narrow nano-channels require high critical electric fields to achieve DNA translocation, leading to short dwell times of DNA in these channels. We demonstrate that nano-funnels integrated with nano-channels reduce the free energy barrier and lower the critical electric field required for DNA translocation. A focused electric field within the funnel increases the electric force on the DNA, compresses the molecule, and increases the osmotic pressure at the nano-channel entrance. This ``electro-osmotic piston'' forces the molecule into the nano-channel at lower electric fields than those observed without the funnel. Appropirately designed nano-funnels can also function as tweezers that allow manipulation of the position of the DNA molecule. The predictions of our theory describing double-stranded DNA behavior in nano-funnel - nano-channel devices are consistent with experimental results. Thanks for the financial support from NSF (DMR-1309892, DMR-1121107, DMR-1122483), NIH (1-P50-HL107168, 1-P01-HL108808-01A1, R01HG02647), NHGRI and CF Foundation.

  5. Radiation synthesis of the nano-scale materials

    Energy Technology Data Exchange (ETDEWEB)

    Yonghong, Ni; Zhicheng, Zhang; Xuewu, Ge; Xiangling, Xu [Department of Applied Chemistry, Univ. of Science and Technology of China, Hefei (China)

    2000-03-01

    Some recent research jobs on fabricating the nano-scale materials via {gamma}-irradiation in our laboratory are simply summarized in this paper. The main contents contain four aspects: (1) the preparation of metal alloy - powders; (2) the fabrication of polymer -metal nano-composites in aqueous solution, micro-emulsion and emulsion systems; (3) the synthesis of metal sulfide nano-particles and (4) the preparation of the ordered nano-structure materials. The corresponding preparation processes are also simply described. (author)

  6. Radiation synthesis of the nano-scale materials

    International Nuclear Information System (INIS)

    Ni Yonghong; Zhang Zhicheng; Ge Xuewu; Xu Xiangling

    2000-01-01

    Some recent research jobs on fabricating the nano-scale materials via γ-irradiation in our laboratory are simply summarized in this paper. The main contents contain four aspects: (1) the preparation of metal alloy - powders; (2) the fabrication of polymer -metal nano-composites in aqueous solution, micro-emulsion and emulsion systems; (3) the synthesis of metal sulfide nano-particles and (4) the preparation of the ordered nano-structure materials. The corresponding preparation processes are also simply described. (author)

  7. Template-assisted growth of nano structured functional materials

    International Nuclear Information System (INIS)

    Ying, K.K.; Nur Ubaidah Saidin; Khuan, N.I.; Suhaila Hani Ilias; Foo, C.T.

    2012-01-01

    Template-assisted growth is an important nano electrochemical deposition technique for synthesizing one-dimensional (1-D) nano structures with uniformly well-controlled shapes and sizes. A good template with well-defined dimensions is imperative for realizing this task. Porous anodic alumina (PAA) has been a favorable candidate for this purpose as it can be tailor-made with precise pore geometries, such as pore length and diameter as well as inter-pore distances, via the anodization of pure aluminium. This paper reports the fabrication of PAA templates and electrochemical synthesis of functional nano structures in the form of nano wires using PAA templates as scaffolds. Axial heterostructure and homogeneous nano wires formed by engineering materials configuration via composition and/ or layer thickness variations were fabricated for different functionalities. X-ray diffraction and imaging techniques were used to alucidate the microstructures, morphologies and chemical compositions of the nano wires produced. Due to their large surface area-to-volume ratios, and therefore high sensitivities, these functional nano structures have useful applications as critical components in nano sensor devices and various areas of nano technology. Potential applications include as hydrogen gas sensors in nuclear power plant for monitoring structural integrity of reactor components and containment building, as well as environmental monitoring of air pollution and leakages of toxic gases and chemicals. (Author)

  8. Anodic Aluminum Oxide Templates for Nano wires Array Fabrication

    International Nuclear Information System (INIS)

    Nur Ubaidah Saidin; Kok, K.Y.; Ng, I.K.

    2011-01-01

    This paper reports on the process developed to fabricate anodic aluminium oxide (AAO) templates suitable for the fabrication of nano wire arrays. Anodization process has been used to fabricate the AAO templates with pore diameters ranging from 15 nm to 30 nm. Electrodeposition of parallel arrays of high aspect ratio nickel nano wires were demonstrated using these fabricated AAO templates. The nano wires produced were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that the orientations of the electrodeposited nickel nano wires were governed by the deposition current and electrolyte conditions. (author)

  9. Preparation and characterization of PVC /ENR/CNTs Nano composites

    International Nuclear Information System (INIS)

    Ratnam, C.T.; Nur Azrini Ramlee; Keong, C.C.

    2011-01-01

    Poly (vinyl chloride), PVC/ epoxidized natural rubber blend, ENR/ carbon nano tubes, CNTs were prepared by using melt and solution blending methods. Addition of 2 phr of CNTs found to cause a drop in the tensile strength, Ts of the 50/ 50 PVC/ ENR blend. The nano composites prepared by the melt blending method exhibited higher values of Ts compared to the nano composites prepared by solution blending. Melt blending found to be an efficient method to prepare PVC/ ENR/ CNTs nano composites. (author)

  10. Nano-based PCMs for building energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Kaushik [ORNL

    2016-01-01

    Thermal storage using phase change materials (PCMs) is seen as a viable method for improving the energy efficiency of buildings. PCMs have been used in building applications in various forms PCM slurries in heat exchangers, macro- or microencapsulated PCMs in building envelopes, bulk PCM for modulating photovoltaic temperatures, etc. In the last decade a new class of PCMs, called nano-enhanced PCM (or nanoPCM), has been extensively investigated with the goal of improving the heat transfer and thermal storage properties of PCMs. NanoPCMs can primarily be categorized as nano-encapsulated PCMs and nanoparticle-PCM composites. The former are nano-sized capsules in which the PCM forms the core and is surrounded by a high-conductivity membrane or shell. The latter consist of PCM supported within nanostructures or nanoparticles dispersed in PCMs. This article reviews the current state of nanoPCM synthesis and characterization of their heat transfer and thermal storage properties. Further, a critical review of nanoPCM applications and their potential energy benefits is performed. Nano-enhanced PCMs exhibit higher thermal conductivities than regular PCM. However, whether the higher conductivity is desirable in all applications and if the property enhancements are worth the cost and effort needed to create nanoPCMs are questions that still need to be answered.

  11. Ge nano-layer fabricated by high-fluence low-energy ion implantation

    International Nuclear Information System (INIS)

    Lu Tiecheng; Dun Shaobo; Hu Qiang; Zhang Songbao; An Zhu; Duan Yanmin; Zhu Sha; Wei Qiangmin; Wang Lumin

    2006-01-01

    A Ge nano-layer embedded in the surface layer of an amorphous SiO 2 film was fabricated by high-fluence low-energy ion implantation. The component, phase, nano-structure and luminescence properties of the nano-layer were studied by means of Rutherford backscattering, glancing incident X-ray diffraction, laser Raman scattering, transmission electron microscopy and photoluminescence. The relation between nano-particle characteristics and ion fluence was also studied. The results indicate that nano-crystalline Ge and nano-amorphous Ge particles coexist in the nano-layer and the ratio of nano-crystalline Ge to nano-particle Ge increases with increasing ion fluence. The intensity of photoluminescence from the nano-layer increases with increasing ion fluence also. Prepared with certain ion fluences, high-density nano-layers composed of uniform-sized nano-particles can be observed

  12. Nano/macro porous bioactive glass scaffold

    Science.gov (United States)

    Wang, Shaojie

    Bioactive glass (BG) and ceramics have been widely studied and developed as implants to replace hard tissues of the musculo-skeletal system, such as bones and teeth. Recently, instead of using bulk materials, which usually do not degrade rapidly enough and may remain in the human body for a long time, the idea of bioscaffold for tissue regeneration has generated much interest. An ideal bioscaffold is a porous material that would not only provide a three-dimensional structure for the regeneration of natural tissue, but also degrade gradually and, eventually be replaced by the natural tissue completely. Among various material choices the nano-macro dual porous BG appears as the most promising candidate for bioscaffold applications. Here macropores facilitate tissue growth while nanopores control degradation and enhance cell response. The surface area, which controls the degradation of scaffold can also be tuned by changing the nanopore size. However, fabrication of such 3D structure with desirable nano and macro pores has remained challenging. In this dissertation, sol-gel process combined with spinodal decomposition or polymer sponge replication method has been developed to fabricate the nano-macro porous BG scaffolds. Macropores up to 100microm are created by freezing polymer induced spinodal structure through sol-gel transition, while larger macropores (>200um) of predetermined size are obtained by the polymer sponge replication technique. The size of nanopores, which are inherent to the sol-gel method of glass fabrication, has been tailored using several approaches: Before gel point, small nanopores are generated using acid catalyst that leads to weakly-branched polymer-like network. On the other hand, larger nanopores are created with the base-catalyzed gel with highly-branched cluster-like structure. After the gel point, the nanostructure can be further modified by manipulating the sintering temperature and/or the ammonia concentration used in the solvent

  13. Electromagnetic brain imaging

    International Nuclear Information System (INIS)

    Sekihara, Kensuke

    2008-01-01

    Present imaging methods of cerebral neuro-activity like brain functional MRI and positron emission tomography (PET) secondarily measure only average activities within a time of the second-order (low time-resolution). In contrast, the electromagnetic brain imaging (EMBI) directly measures the faint magnetic field (10 -12 -10 -13 T) yielded by the cerebral activity with use of multiple arrayed sensors equipped on the head surface within a time of sub-millisecond order (high time-resolution). The sensor array technology to find the signal source from the measured data is common in wide areas like signal procession for radar, sonar, and epicenter detection by seismic wave. For estimating and reconstructing the active region in the brain in EMBI, the efficient method must be developed and this paper describes the direct and inverse problems concerned in signal and image processions of EMBI. The direct problem involves the cerebral magnetic field/lead field matrix and inverse problem for reconstruction of signal source, the MUSIC (multiple signal classification) algorithm, GLRT (generalized likelihood ratio test) scan, and adaptive beamformer. As an example, given are results of magnetic intensity changes (unit, fT) in the somatosensory cortex vs time (msec) measured by 160 sensors and of images reconstructed from EMBI and MRI during electric muscle afferent input from the hand. The real-time imaging is thus possible with EMBI and extremely, the EMBI image, the real-time cerebral signals, can inversely operate a machine, of which application directs toward the brain/machine interface development. (R.T.)

  14. Plasma-arc reactor for production possibility of powdered nano-size materials

    International Nuclear Information System (INIS)

    Hadzhiyski, V; Mihovsky, M; Gavrilova, R

    2011-01-01

    Nano-size materials of various chemical compositions find increasing application in life nowadays due to some of their unique properties. Plasma technologies are widely used in the production of a range of powdered nano-size materials (metals, alloys, oxides, nitrides, carbides, borides, carbonitrides, etc.), that have relatively high melting temperatures. Until recently, the so-called RF-plasma generated in induction plasma torches was most frequently applied. The subject of this paper is the developments of a new type of plasma-arc reactor, operated with transferred arc system for production of disperse nano-size materials. The new characteristics of the PLASMALAB reactor are the method of feeding the charge, plasma arc control and anode design. The disperse charge is fed by a charge feeding system operating on gravity principle through a hollow cathode of an arc plasma torch situated along the axis of a water-cooled wall vertical tubular reactor. The powdered material is brought into the zone of a plasma space generated by the DC rotating transferred plasma arc. The arc is subjected to Auto-Electro-Magnetic Rotation (AEMR) by an inductor serially connected to the anode circuit. The anode is in the form of a water-cooled copper ring. It is mounted concentrically within the cylindrical reactor, with its lower part electrically insulated from it. The electric parameters of the arc in the reactor and the quantity of processed charge are maintained at a level permitting generation of a volumetric plasma discharge. This mode enables one to attain high mean mass temperature while the processed disperse material flows along the reactor axis through the plasma zone where the main physico-chemical processes take place. The product obtained leaves the reactor through the annular anode, from where it enters a cooling chamber for fixing the produced nano-structure. Experiments for AlN synthesis from aluminium power and nitrogen were carried out using the plasma reactor

  15. Interaction of NANOS2 and NANOS3 with different components of the CNOT complex may contribute to the functional differences in mouse male germ cells

    OpenAIRE

    Atsushi Suzuki; Yuki Niimi; Yumiko Saga

    2014-01-01

    ABSTRACT NANOS2 and NANOS3 belong to the Nanos family of proteins that contain a conserved zinc finger domain, which consists of two consecutive CCHC-type zinc finger motifs, and contribute to germ cell development in mice. Previous studies indicate that there are redundant and distinct functions of these two proteins. NANOS2 rescues NANOS3 functions in the maintenance of primordial germ cells, whereas NANOS3 fails to replace NANOS2 functions in the male germ cell pathway. However, the lack o...

  16. The investigation of nano-monitoring technology and the probability analysis of application of nuclear technology

    International Nuclear Information System (INIS)

    Kang Kejun; Wang Xuewu; Gao Wenhuan

    1999-01-01

    After several-decade of development, nano science/nano technology has become a scientific and technical frontier that with major trends foreseen in several disciplines. By connecting with the development of nano science/nano technology and considering the human body environment that the nano system is applicable in, the author analyzes the probability of the present nuclear detection technologies integrating and application with the monitoring of nano system, and draws an analysis of optimality choice

  17. The effect of brushing with nano calcium carbonate and calcium carbonate toothpaste on the surface roughness of nano-ionomer

    Science.gov (United States)

    Anisja, D. H.; Indrani, D. J.; Herda, E.

    2017-08-01

    Nanotechnology developments in dentistry have resulted in the development of nano-ionomer, a new restorative material. The surface roughness of restorative materials can increase bacteria adhesion and lead to poor oral hygiene. Abrasive agents in toothpaste can alter tooth and restorative material surfaces. The aim of this study is to identify the effect of brushing with nano calcium carbonate, and calcium carbonate toothpaste on surface roughness of nano-ionomer. Eighteen nano-ionomer specimens were brushed with Aquabidest (doubledistilled water), nano calcium carbonate and calcium carbonate toothpaste. Brushing lasted 30 minutes, and the roughness value (Ra) was measured after each 10 minute segment using a surface roughness tester. The data was analyzed using repeated ANOVA and one-way ANOVA test. The value of nano-ionomer surface roughness increased significantly (p<0.05) after 20 minutes of brushing with the nano calcium carbonate toothpaste. Brushing with calcium carbonate toothpaste leaves nano-ionomer surfaces more rugged than brushing with nano calcium carbonate toothpaste.

  18. Study the scratch resistance of UV-cured epoxy acrylate in the presence of nano alumina particles via nano indentation

    International Nuclear Information System (INIS)

    Bastani, S.; Ebrahimi, M.; Kardar, P.

    2007-01-01

    In this research, an epoxy acrylate resin was synthesized, then the synthesized resin was used along with different multifunctional acrylate monomers and with a photoinitiator in different formulations and cured with UV radiation. The experiments were designed based on mixture method by using Design-Expert software. To investigate the effect of nano particles on the some of physical and mechanical properties of the UV cured resins, the suspension of nano alumina in TPGDA, was used in formulations. The hardness of prepared films was evaluated by using konig hardness tester and nano indentater. The scratch resistance and gloss of the films were also determined. The results showed that the visibility of scratch decreased when the nano particles were used. It seems that the self-healing property of the film improved in the presence of nano particles. The hardness of the samples with nano particles was found to be less than that the samples of without any nano particles. It was observed that the gloss of the films with the nano particles, almost was the same as the film without nano particles. (Author)

  19. Label it or ban it? Public perceptions of nano-food labels and propositions for banning nano-food applications

    Science.gov (United States)

    Chuah, Agnes S. F.; Leong, Alisius D.; Cummings, Christopher L.; Ho, Shirley S.

    2018-02-01

    The future of nano-food largely hinges on public perceptions and willingness to accept this novel technology. The present study utilizes the scientific literacy model and psychometric paradigm as the key theoretical frameworks to examine the factors influencing public support for labeling and banning of nano-food in Singapore. Using data collected from a nationally representative survey of 1001 respondents, the findings demonstrated that attitudes toward technology, preference for natural product, science knowledge, and risk perception were found to substantially affect public support for both labeling and banning of nano-food. Conversely, attention to food safety news on traditional media and attention to nano-news on new media were only associated with public support for labeling of nano-food. Similarly, benefit perception was only significantly associated with public support for banning of nano-food. Theoretically, these findings support the growing body of literature that argues for the significant role played by predispositions, media use, science knowledge, and risk and benefit perceptions on attitude formation toward nano-food. It serves as the pioneering piece to address the aspect of banning in the field of nano-food. Practically, insights drawn from this study could aid relevant stakeholders in enlisting effecting strategies to convey the benefits of nano-food while mitigating the risk perceptions among the public.

  20. Control of the Nano-Particle Weight Ratio in Stainless Steel Micro and Nano Powders by Radio Frequency Plasma Treatment

    OpenAIRE

    Dong-Yeol Yang; Youngja Kim; Min Young Hur; Hae June Lee; Yong-Jin Kim; Tae-Soo Lim; Ki-Bong Kim; Sangsun Yang

    2015-01-01

    This study describes how to make stainless steel hybrid micro-nano-powders (a mixture of micro-powder and nano-powder) using an in situ one-step process via radio frequency (RF) thermal plasma treatment. Nano-particles attached to micro-powders were successfully prepared by RF thermal plasma treatment of stainless steel powder with an average size of 35 μm. The ratio of nano-powders is estimated with a two-dimensional fluid simulation that calculates the temperature profile influencing the r...