CA2 IMAGING OF THE LIVING BRAIN USING MULTI CELL BOLUS LOADING TECHNIQUE

Tìm thấy 10,000 tài liệu liên quan tới từ khóa "CA2 IMAGING OF THE LIVING BRAIN USING MULTI CELL BOLUS LOADING TECHNIQUE":

Cell Metabolism Cell Homeostasis and Stress Response Part 15 doc

CELL METABOLISM CELL HOMEOSTASIS AND STRESS RESPONSE PART 15 DOC

Imaging Cellular Metabolism 201 address such questions, it will be important to analyze cell cycle dependent events in large numbers of cells. A very promising new technique for measuring cell cycle dependent growth was demonstrated recently, using spatial light interference microscopy (SLIM) coupled with a fluorescence marker for S-phase to analyze cell cycle phase within a cell population (Mir et al., 2011). The applications for this technique to a range of cell types, as well as to microscopy systems that utilize multi-channel fluorescence imaging, open endless possibilities for developing variations on this method to image cellular metabolism in the context of cell growth even within a complex cellular population. 5. Conclusion The rapid progress recently made toward developing metabolic tracer molecules shows great promise for new applications in clinical diagnostics. Further characterization of novel imaging probes is needed to understand how they can be used to image and identify malignant tissues. Rapidly screening novel tracer molecules for efficacy in identifying tumors in cell culture systems, animal models and clinical trials is a crucial ongoing challenge aimed toward building a battery of tools for imaging cancer metabolism in patients. Feeding into clinical studies is a vast amount of knowledge gained from basic research characterizing metabolic pathways in single cells. This information has potential for wide use for diagnostic imaging, but awaits further research and development into translational medicine that will utilize novel biomarkers and imaging technologies. Finally, continued development of super-resolution imaging platforms for both basic research and clinical use are certain to have a major impact on our understanding of molecular complexes, especially with regard to colocalization of specific protein-protein, protein-RNA or protein-DNA complexes within the overall context of cellular architecture. 6. References Amiel, A., Litmanovitch T., Lishner M., Mor A., Gaber E., Tangi I., Fejgin M. & Avivi, L. 1998. Temporal differences in replication timing of homologous loci in malignant cells derived from CML and lymphoma patients. Genes Chromosomes Cancer 22: 225–231.
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báo cáo hóa học:" Immunological considerations of modern animal models of malignant primary brain tumors" doc

BÁO CÁO HÓA HỌC:" IMMUNOLOGICAL CONSIDERATIONS OF MODERN ANIMAL MODELS OF MALIGNANT PRIMARY BRAIN TUMORS" DOC

though of low incidence in relation to many adult solidtumors, represent a disproportionately large fraction ofcancer deaths due to their highly aggressive and fatal char-acter. For example, Glioblastoma Multiforme (GBM), themost common and malignant brain tumor of adults, car-ries a median survival of less than 1 year. While currentapproaches to brain tumor therapy, including surgicalresection, radiotherapy, and either systemic or local chem-otherapy with either nitrosoureas or temozolamide,appear to prolong survival for patients with CNS cancers,the modest effect of these therapies, and their associatedmorbidity, has left investigators in search of alternativeand novel treatments to extend quantity and quality of lifefor affected patients [1].The nearly infinite flexibility and remarkable cellular spe-cificity of the human immune response makes immunebased approaches an attractive option to current therapy,which either crudely target entire regions of the brain (e.g.surgery, radiation), or potentially interfere with the cellu-lar metabolism of all dividing cells in the body (e.g.alkylating agents). However, immunotherapy is not with-out technical barriers, which have hindered its incorpora-Published: 8 October 2009Journal of Translational Medicine 2009, 7:84 doi:10.1186/1479-5876-7-84Received: 8 July 2009Accepted: 8 October 2009This article is available from: http://www.translational-medicine.com/content/7/1/84© 2009 Sughrue et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0),
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Tài liệu Báo cáo khoa học: It is all about resolution Meeting report based upon presentations at the 10th International Global BioMillennium 2006 symposium on molecular cell biology (Tbilisi, Georgia) docx

TÀI LIỆU BÁO CÁO KHOA HỌC: IT IS ALL ABOUT RESOLUTION MEETING REPORT BASED UPON PRESENTATIONS AT THE 10TH INTERNATIONAL GLOBAL BIOMILLENNIUM 2006 SYMPOSIUM ON MOLECULAR CELL BIOLOGY (TBILISI, GEORGIA) DOCX

sequence conservation, suggesting that ribosomesevolved by gene fusion. Antibiotics complexed withribosomes from an archaeon that shares propertieswith eukaryotes illuminated the structural elementsrequired for therapeutic effectiveness. Structural bio-logy can hence become a key tool for developingnovel antibiotics.Post-translational regulation was discussed by AaronCiechanover (Haifa, Israel), who argued that theubiquitin proteolytic system covers the pathway forelucidating the basic mechanisms that are pivotal fordrug targeting. Degradation of cellular proteins playsmajor roles in a multitude of basic pathways duringcell life and death, in both health and disease. Theubiquitin–proteasome pathway involves conjugation ofmultiple ubiquitin moieties to the substrate and subse-quent degradation of the tagged protein, whichinvolves the downstream 26S proteasome complex andunknown mechanisms. The common thread in all ofthese topics is far greater complexity than was previ-ously perceived, and the need for methods that achievethe maximum resolution.Imaging genomic and cellular propertiesDifferent technologies dealing with real-time imagingof molecular events, which has become a major tool inbiological research, were presented.Hans J. Tanke (Leiden, the Netherlands) describedcellular imaging of telomere localization and dynamicsin normal cells and in cancer cells using a fluorescentlylabeled peptide nucleic acid probe with a sequence
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ultrasonic measurement of residual stresses

ULTRASONIC MEASUREMENT OF RESIDUAL STRESSES

Ultrasonic Measurement of Residual Stresses in Welded Elements and Structures Yuri Kudryavtsev and Jacob Kleiman Structural Integrity Technologies Inc., 80 Esna Park Drive, Units 7-9, Markham, Ontario, L3R 2R7, Canada ykudryavtsev@sintec.ca Keywords: Residual Stresses, Ultrasonic Measurement, Welded Elements, Fatigue Tests, Relaxation of Residual Stresses Abstract. The objective of the study described in this paper is to identify the residual stress distribution and relaxation in standard welded specimens as well as in a large-scale welded panel imitating the critical, from the fatigue point of view, zones of ship structure. The residual stresses were measured after welding and in the process of fatigue loading of welded elements by the UltraMARS system that is based on using ultrasound. The measurements had shown that the maximum residual stresses near the welds (4-5mm away from the weld) reach levels 290-320 MPa that are close to the yield strength of considered material both in welded specimens and in the large scale panel. Analysis of residual stress relaxation in the welded panel under the action of cyclic loading confirmed the fact that within the interval of applied stress ranges corresponding to the multi-cycle region of loading of the welded joints, the relaxation of residual stresses occurs mainly during the first cycle. The results of residual stress measurements in welded elements were compared with the results of computation based on advanced finite element model. Introduction Residual stresses (RS) can significantly affect engineering properties of materials and structural components, notably fatigue life, distortion, dimensional stability, corrosion resistance, brittle fracture [1]. Systematic studies had shown that, for instance, welding RS might lead to a drastic reduction in fatigue strength of welded elements [2]. In multi-cycle fatigue (N>106
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CONCISE ENCYCLOPEDIA OF BRAIN AND LANGUAGE pdf

CONCISE ENCYCLOPEDIA OF BRAIN AND LANGUAGE PDF

Neuroscience,theEncyclopedia of Gerontology an d the Handbook of the Neuroscience of Language. The articles are broadly dividedinto 11 topics, listed here and outlined in greater detail immediately below: (1) functional and structural brain imaging oflanguage, (2) hemispheric asymmetries and the lateralization of language, (3) disorders of language, (4) neurologicalsymptoms and their language sequelae, (5) the auditory system, (6) testing, the assessment of language disorders, (7) thetreatment and rehabilitation of persons with aphasia and cognitive disorders (8) recovery from aphasia and brain damage.The remaining three divisions broaden the scope of this collection of papers: (9) the principles of psycholinguisticanalysis, essential for understanding language and language disorders, (10) normal brain processes that directly interactwith the language system and (11) memory and memory disorders, understood since the 19th century to be inextricablybound up with language and language disorders.In more detail, the first division of the Concise Encyclopedia of Brain and Language contains eight articles on imaginglanguage in the brain; there is one overview article reviewing techniques in general and techniques specific to cognitiveprocessing followed by seven articles covering all the major techniques used in language research: diffusion and perfusionimaging, direct electrical brain stimulation of both the cortical surface and deep structures, event-related (evoked)potentials, functional magnetic resonance imaging, the intracarotid sodium amobarbital procedure, positron emissiontomography, and transcranial magnetic stimulation. The second division contains ten articles featuring brain hemi-spheric asymmetries and the lateralization of language representation, approached from a variety of behavioral andimaging techniques. Division three is the largest division, thirty two articles focusing on disorders of language. There areeleven general articles that review a variety
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báo cáo hóa học: " Gait analysis methods in rehabilitation" pot

BÁO CÁO HÓA HỌC: " GAIT ANALYSIS METHODS IN REHABILITATION" POT

under-lying bones are now the principal problems. Techniques for using functional tests todetermine joint centres and axes of rotation are starting to be used successfully. Probably the lastgreat challenge for optical systems is in using computational techniques to compensate for softtissue measurements. In the long term future it is possible that direct imaging of bones and jointsin three dimensions (using MRI or fluoroscopy) may replace marker based systems.Methods for interpreting gait analysis data: There is still not an accepted general theory ofwhy we walk the way we do. In the absence of this, many explanations of walking address themechanisms by which specific movements are achieved by particular muscles. A whole newmethodology is developing to determine the functions of individual muscles. This needs furtherdevelopment and validation. A particular requirement is for subject specific models incorporating3-dimensional imaging data of the musculo-skeletal anatomy with kinematic and kinetic data.Methods for understanding the effects of intervention: Clinical gait analysis is extremelylimited if it does not allow clinicians to choose between alternative possible interventions or topredict outcomes. This can be achieved either by rigorously planned clinical trials or usingtheoretical models. The evidence base is generally poor partly because of the limited number ofprospective clinical trials that have been completed and more such studies are essential. Veryrecent work has started to show the potential of using models of the mechanisms by which peoplewith pathology walk in order to simulate different potential interventions. The development ofthese models offers considerable promise for new clinical applications of gait analysis.Published: 02 March 2006Journal of NeuroEngineering and Rehabilitation2006, 3:4 doi:10.1186/1743-0003-3-4Received: 29 April 2005Accepted: 02 March 2006This article is available from: http://www.jneuroengrehab.com/content/3/1/4© 2006Baker; licensee BioMed Central Ltd.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Journal of NeuroEngineering and Rehabilitation 2006, 3:4 http://www.jneuroengrehab.com/content/3/1/4Page 2 of 10
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Food Biotechnology

FOOD BIOTECHNOLOGY

Genes determine traits by controlling the productionof proteins, including enzymes. Proteins and enzymesare used by all living organisms to grow, metabolize en-ergy, and become what their genetic code dictates. EachFood BiotechnologyJ.L. Tietyen and M.E. Garrison, Family and Consumer Sciences;R.T. Bessin, Department of Entomology; D.F. Hildebrand, Department of AgronomyThis publication is part of a series that seeks to provide science-based information about discoveries in agricultural biotechnology.The information in these publications comes from the Biotechnology Research and Education Initiative (BREI) committee, which iscomprised of a multi-disciplinary team of research, extension, and teaching professionals from the College of Agriculture. The seriesis designed to help Kentuckians understand and assess the risks and benefits of agricultural biotechnology.DNA directs the processes of life.2cell of an organism contains the entire genetic code neededto create the organism. The interaction of genetic makeupand environmental factors shapes the nature of all livingthings. When people eat a healthy diet, they are con-trolling environmental factors that will, within the limitsof their genetic makeup, decrease their risk of develop-ing a disease.From Breeders to Gene JockeysPlant breeders have for many years used tools andtechniques such as selective hybridization grafting andcell isolation to improve crop quality and yield. Andthese early agricultural scientists made great advances,producing juicy ears of corn instead of hard-kerneledcorn, which must be ground into flour, and present-daykiwi fruits rather than the hard berry from which theywere developed.Scientists using the relatively new tools of biotechnol-
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báo cáo hóa học: " Syndecan-1 antigen, a promising new target for triple-negative breast cancer immuno-PET and " potx

BÁO CÁO HÓA HỌC: " SYNDECAN-1 ANTIGEN, A PROMISING NEW TARGET FOR TRIPLE-NEGATIVE BREAST CANCER IMMUNO-PET AND " POTX

15. Supiot S, Faivre-Chauvet A, Couturier O, Heymann MF, Robillard N, Kraeber-Bodere F, Morandaeu L, Mahé MA, Chérel M: Comparison of the biologiceffects of MA5 and B-B4 monoclonal antibody labeled with iodine-131and bismuth-213 on multiple myeloma. Cancer 2002, 94(4Suppl):1202-1209.16. DeNardo SJ, O’Grady LF, Richman CM, DeNardo GL: Overview ofradioimmunotherapy in advanced breast cancer using I-131 chimeric L6.Adv Exp Med Biol 1994, 353:203-211.17. Schrier DM, Stemmer SM, Johnson T, Kasliwal R, Lear J, Matthes S, Taffs S,Dufton C, Glenn SD, Butchko G, Ceriani RL, Rovira D, Bunn P, Shpall EJ,Bearman SI, Purdy M, Cagnoni P, Jones RB: High-dose 90Y Mx-diethylenetriaminepentaacetic acid (DTPA)-BrE-3 and autologoushematopoietic stem cell support (AHSCS) for the treatment of advancedbreast cancer: a phase I trial. Cancer Res 1995, 55(23 Suppl):5921s-5924s.18. Behr TM, Sharkey RM, Juweid ME, Dunn RM, Vagg RC, Ying Z, Zhang CH,Swayne LC, Vardi Y, Siegel JA, Goldenberg DM: Phase I/II clinicalradioimmunotherapy with an iodine-131-labeled anti-carcinoembryonicantigen murine monoclonal antibody IgG. J Nucl Med 1997, 38(6):858-870.19. Mulligan T, Carrasquillo JA, Chung Y, Milenic DE, Schlom J, Feuerstein I,Paik C, Perentesis P, Reynolds J, Curt G, Goeckeler W, Fordyce W, Cheng R,Riseberg D, Cowan K, O’Shauffnessy J: Phase I study of intravenous Lu-labeled CC49 murine monoclonal antibody in patients with advancedadenocarcinoma. Clin Cancer Res 1995, 1(12):1447-1454.20. Oliveras-Ferraros C, Vazquez-Martin A, Lopez-Bonet E, Martin-Castillo B, DelBarco S, Brunet J, Menendez JA: Growth and molecular interactions of theanti-EGFR antibody cetuximab and the DNA cross-linking agent cisplatinin gefitinib-resistant MDA-MB-468 cells: new prospects in the treatmentof triple-negative/basal-like breast cancer. Int J Oncol 2008,33(6):1165-1176.21. Bernardeau K, Gouard S, David G, Ruellan AL, Devys A, Barbet J,
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báo cáo hóa học: " Proinflammatory and proapoptotic markers in relation to mono and di-cations in plasma of autistic patients from Saudi Arabia" docx

BÁO CÁO HÓA HỌC PROINFLAMMATORY AND PROAPOPTOTIC MARKERS IN RELATION TO MONO AND DI CATIONS IN PLASMA OF AUTISTIC PATIENTS FROM SAUDI ARABIA DOCX

34. Stys PK, Lopachin RM: Mechanisms of calcium and sodium fluxes inanoxic myelinated central nervous system axons. Neuroscience 1998,82:21-32.35. Banasiak KJ, Burenkova O, Haddad GG: Activation of voltage-sensitivesodium channels during oxygen deprivation leads to apoptotic neuronaldeath. Neuroscience 2004, 126:31-44.36. Galland L: Magnesium, stress and neuropsychiatric disorders. MagnesTrace Elem 1992, 10(Suppl 2-4):287-301.37. Iotti S, Malucelli E: In vivo assessment of Mg2+ in human brain andskeletal muscle by 31P-MRS. Magnes Res 2008, 21(Suppl 3):157-62.38. Faulker WR, Meites S: Selected methods for the small clinical chemistrylaboratory Washington, DC; 1982.39. Henry RL, Cannon DC, Winklemen JW: Clinical Chemistry Principles andTechniques. 2 edition. Hagerstown, MD: Harper and Row; 1974.40. Tietz NW: Fundamentals of Clinical Chemistry WB, Saunder Co, Philadelphia,PA; 1982, 874.41. Lindstrom F, Diehl H: Indicator for the titration of calcium plusmagnesium with (ethylenedinitrilo)tetraacetate. Anal Chem 1960, 32:1123.42. Klein B, Oklander M: Clin Chem 1976, 13:26.43. Rees S, Harding R, Walker D: The biological basis of injury andneuroprotection in the fetal and neonatal brain. Int J Devl Neuroscience .44. Dalitz P, Harding R, Rees SM, Cock ML: Prolonged reductions in placen- talblood flow and cerebral oxygen delivery in preterm fetals heep exposedto endotoxin: possible factors in white matter injury after acuteinfection. J Soc Gynecol Investig 2003, 10:283-290.45. Duncan JR, Cock ML, Suzuki K, Scheerlinck JP, Harding R, Rees SM: Chronicendo toxin exposure causes brain injury in the ovine fetus in theabsence of hypoxemia. J Soc Gynecol Investig 2006, 13:87-96.46. Yan E, Castillo-Melendez M, Nicholls T, Hirst J, Walker D: Cerebrovascu- larresponses in the fetal sheep brain to low-dose endotoxin. Pediatr Res
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Bioluminescence Recent Advances in Oceanic Measurements and Laboratory Applications Part 5 ppt

BIOLUMINESCENCE RECENT ADVANCES IN OCEANIC MEASUREMENTS AND LABORATORY APPLICATIONS PART 5 PPT

introduced in a cell in addition to the level of its counterpart expressed inside a cell, it will have some direct physical effect on a number of other proteins. These new interactions may cause some changes in the functional aspects of several other proteins. Such effects can be felt right across the protein interaction network, most often becoming less significant as the distance of the new protein from the other protein increases. It is also possible for genetically modified cells to produce a new protein that will display completely new patterns of protein interactions. This may not be evident until the cells find themselves in some unusual circumstances. They may then respond in a very different way from wild-type cells. Although the genetically engineered cells may appear to behave just like wild-type cells, this cannot be guaranteed under all circumstances (Becker et al., 1990; Beeckmans 1999; Bode and Willmitzer 1975). However the techniques currently available for inserting new DNA into the chromosomes of cells do not have any specific control mechanisms, capable of directing the point of insertion in the organism's existing genome without producing significant impact on the expression level of any of the endogenous proteins. Of the gene delivery systems currently available, the adeno-associated virus is the only viral mediated vector which can normally introduce and integrate a single copy of the transgene specifically into human chromosome loci at 19 (19q13.3-qter). Otherwise, it is customary to produce millions of cells with the new DNA inserted at essentially random positions in the hope of producing at least some “hits.” Screening is then conducted to find those cells, which must survive the engineering process and also express the newly inserted gene. These survivors are then subjected to further screenings to find those that seem to behave most like the wild-type, and yet possessing the new, desired, engineered properties. It is generally assumed that any harm to an organism as a result of inserting a new gene will be observed as a change in gross characteristics of the organism (Stopeck et al., 1998). 1.7 Biological importance in studying protein folding As discussed in the previous sections, proteins are cellular macromolecules with complex structural and functional properties. Dysfunctional protein folding represents the Bioluminescent Proteins: High Sensitive Optical Reporters for Imaging Protein-Protein Interactions and Protein Foldings in Living Animals
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Advances in Solid State Part 12 pot

ADVANCES IN SOLID STATE PART 12 POT

proposed. Since flash memory cell consists of one cell transistor in a memory cell and no contact is needed to source and drain in a string of cell transistors, the multi-stack is relatively easier than that of DRAM. On the other hand, field-effect transistor itself will encounter the ultimate size limit of 5-10 nm. Only about several tens of silicon atoms exist in the channel region of 10-nm transistor. Normal filed-effect operation will be impossible due to fatal short-channel effects in that dimension range. Particularly a ratio of off current to on current becomes worse causing unacceptably large stand-by power consumption. If the scaling pace is still kept constant, the ultimate limit will be encountered within 15 years. Forecasting the limitation, various kinds of 3-D transistors have been proposed, however, they will still suffer from the short-channel effects same as 2-D transistors. Due to a limitation of invariable channel length of vertical transistor, it will be practical in products that the vertical transistor is employed together with 2-D one in an LSI chip. To cope with these fundamental limits in miniaturization of devices, various kinds of chip stack will be dominant in LSI products in response to the requirement for smaller package used in personal-use, hand-held products. Advances in Solid State Circuits Technologies 330 7. Acknowledgements The author wishes to thank all of colleagues, who have done research and development with respect to trench capacitors and 3-D transistors together with him, M. Koyanagi, K. Itoh, T. Kure, Y. Kawamoto, S. Iijima, M. Ohkura, S. Kimura, T. Kaga, R. Hori, T. Toyabe, T. Furukawa, S. Matsumura, A. Sugimura, and K. Okumura for their cooperation. He is also thankful to N. Hashimoto, S. Asai, M. Kubo, and S. Harada for their continuous encouragement. 8. References Choi, Y K.; Lindert, N.; Xuan, P.; Tang, S.; Ha, D.; Anderson, E.; King,T J.; Bokor, J. and Hu, C. (2001). Sub-20nm CMOS FinFET technologies, IEDM Tech. Dig., pp. 421-424, December 2001, Washington, D. C.
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Báo cáo hóa học: " Brain perfusion CT compared with15O-H2O-PET in healthy subjects" pdf

BÁO CÁO HÓA HỌC: " BRAIN PERFUSION CT COMPARED WITH15O-H2O-PET IN HEALTHY SUBJECTS" PDF

Neuroradiology 2004, 46:s194-s200.2. Coles JP: Imaging of cerebral blood flow and metabolism. Curr OpinAnaesthesiol 2006, 19:473-480.3. Waldemar G: Functional brain imaging with SPECT in normal aging anddementia. Methodological, pathophysiological, and diagnostic aspects.Cerebrovasc Brain Metab Rev 1995, 7:89-130.4. Cha S: Update on brain tumor imaging: from anatomy to physiology.AJNR Am J Neuroradiol 2006, 27:475-487.5. Aref M, Chaudhari AR, Bailey KL, Aref S, Wiener EC: Comparison of tumorhistology to dynamic contrast enhanced magnetic resonance imaging-based physiological estimates. Magn Reson Imaging 2008, 26:1279-1293.6. Kudo K, Terae S, Katoh C, Oka M, Shiga T, Tamaki N, Miyasaka K:Quantitative cerebral blood flow measurement with dynamic perfusionCT using the vascular-pixel elimination method: comparison with H2(15)O positron emission tomography. AJNR Am J Neuroradiol 2003, 24:419-426.7. Law I, Iida H, Holm S, Nour S, Rostrup E, Svarer C, Paulson OB, :Quantitation of regional cerebral blood flow corrected for partialvolume effect using O-15 water and PET: II. Normal values and graymatter blood flow response to visual activation. J Cereb Blood Flow Metab2000, 20:1252-1263.8. Iida H, Law I, Pakkenberg B, Krarup-Hansen A, Eberl S, Holm S, Hansen AK,Gundersen HJ, Thomsen C, Svarer C, Ring P, Friberg L, Paulson OB:Quantitation of regional cerebral blood flow corrected for partialvolume effect using O-15 water and PET: I. Theory, error analysis, andstereologic comparison. J Cereb Blood Flow Metab 2000, 20:1237-1251.9. Miles KA: Perfusion imaging with computed tomography: brain andbeyond. Eur Radiol 2006, 16:M37-M43.10. Chen W: Clinical applications of PET in brain tumors. J Nucl Med 2007,48:1468-1481.11. Bruehlmeier M, Roelcke U, Schubiger PA, Ametamey SM: Assessment of
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Independent component analysis P22

INDEPENDENT COMPONENT ANALYSIS P22

considering the underlying source signals as stochastic processes, the requirementof stationarity is in theory necessary to guarantee the existence of a representativedistribution of the ICs. Yet, in the implementation of batch ICA algorithms, the dataare considered as random variables, and their distributions are estimated from thewhole data set. Thus, the nonstationarity of the signals is not really a violation of theassumptions of the model. On the other hand, the stationarity of the mixing matrix Ais crucial. Fortunately, this assumption agrees with widely accepted neuronal sourcemodels [394, 309].410BRAIN IMAGING APPLICATIONS22.2 ARTIFACT IDENTIFICATION FROM EEG AND MEGAs a first application of ICA on EEG and MEG signals, we consider separation ofartifacts. Artifacts mean signals not generated by brain activity, but by some externaldisturbances, such as muscle activity. A typical example is ocular artifacts, generatedby eye muscle activity.A review on artifact identification and removal,with special emphasis on the ocularones, can be found in [56, 445]. The simplest, and most widely used method consistsof discarding the portions of the recordings containing attributes (e.g., amplitudepeak, frequency contents, variance and slope) that are typical of artifacts and exceeda determined threshold. This may lead to significant loss of data, and to completeinability of studying interesting brain activity occuring near or during strong eyeactivity, such as in visual tracking experiments.Other methods include the subtraction of a regression portion of one or moreadditional inputs (e.g., from electrooculograms, electrocardiograms, or electromyo-grams) from the measured signals. This technique is more likely to be used in EEGrecordings, but may, in some situations, be applied to MEG. It should be noted thatthis technique may lead to the insertion of undesirable new artifacts into the brainrecordings [221]. Further methods include the signal-space projection [190], andsubtracting the contributions of modeled dipoles accounting for the artifact [45]. Inboth of these latter methods we need either a good model of the artifactual source
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Báo cáo khoa học: Mitochondrial calcium signalling in cell death Delivered on 1 July 2004 at the 29th FEBS Congress in Warsaw pptx

BÁO CÁO KHOA HỌC: MITOCHONDRIAL CALCIUM SIGNALLING IN CELL DEATH DELIVERED ON 1 JULY 2004 AT THE 29TH FEBS CONGRESS IN WARSAW PPTX

rial matrix and was instrumental in gaining new insightinto mitochondrial Ca2+handling, i.e. the topic of thisreview [13]. In the chimeric cDNA, an aequorin moietyincluding an HA1 tag was fused in frame with theN-terminal portion (including the 25 amino acidscleavable presequence and the first eight amino acidsof the mature polypeptide) of subunit VIII of cyto-chrome c oxidase (COX8). The fusion protein, whenexpressed in mammalian cells, is entirely distributedto the mitochondria (Fig. 1B). The localization ofmtAEQ is revealed by immunofluorescence using anantibody that recognizes the HA1 domain.In general, targeted aequorins (also developed forother intracellular compartments using similar strat-egies) have proved to be extremely valuable, andallowed many new data and novel concepts in Ca2+signalling to be obtained. The most important onesABFig. 1. Schematic map of the mtAEQ construct (aequorin targetedto the mitochondrial matrix) and its localization by immunofluores-cence.Mitochondrial calcium signalling in cell death S. Leo et al.4014 FEBS Journal 272 (2005) 4013–4022 ª 2005 FEBSnot covered in this review are the estimates of ER[Ca2+
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State of the Elderly in Singapore 2008/2009 potx

STATE OF THE ELDERLY IN SINGAPORE 2008/2009 POTX

100.0 100.0 100.0 N* 53,570 53,570 53,357 53,357 74,593 74,187 * Excluding non-response cases Programmes and Services for Ageing- in-Place The Housing and Development Board (HDB) has initiated various schemes to encourage the elderly and their children to stay with or near each other for mutual care and support, such as Married Child Priority Scheme, Multi-Generation Living Scheme, Higher-tier Family CPF Housing Grant, Higher-tier Singles CPF Housing Grant and higher income ceiling for extended families. The elderly could also sublet their whole flat and move in with their married children or rightsize to a smaller flat or Studio Apartment to stay near them. Alternatively, the elderly could continue to stay in their own flats and rent out a room for an income. Eligible elderly who own a 3-room or smaller flat could also apply for the Lease Buyback Scheme which allows them to remain in their existing flats for the next 30 years while enjoying a lifelong stream of annuity payout to supplement their retirement income. To enable the elderly to live in the community rather than an institution, HDB has put in place several programmes for existing estates. HDB works closely with Town Councils to give them technical advice on Barrier-free accessibility (BFA) programme to improve the accessibility in HDB estates . Apart from this ,HDB has also been carrying out Lift Upgrading Programmes (LUP) to provide full lift access to eligible HDB blocks, Home Improvement 40.6
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Laser Welding Part 10 pptx

LASER WELDING PART 10 PPTX

with tag points in a virtual environment. The robot program is accomplished based on these information by using GSL (Graphic Simulation Language). After fully examining the accessibility of optic head to all stitches, the collisions with equipments such as jig etc., the welding parameters for the secure of quality, the applicability of sensor to tracing welding path and the operation sequences for preventing from distortion of parts, the program is generated to execute the events offered from the sequence diagram. Three types of the proposed configuration of cell are evaluated through the simulation of laser welding for the side panel with the generated program. The evaluation regarding to technology is done in terms of cycle time related to productivity, minimization shortest moving distance, automation degree, flexibility, available space and possibility of modular system adapting to change of manufacturing environment and so on. From the organization and economy point of view, the terms of expansion ability, control logic, interface between stations and investment and operating cost are chosen for the evaluation. As the result of evaluation, the cell configuration having the parallel arrangement of two robots is selected as optimal due to high score in the load balancing of each robot(the cycle time of each robot is 47.1 sec and 48 sec) and the minimal area required for implementation. The total cycle time for welding the side panel is also saved 3 sec compared to two another cell configurations. In addition, the selected cell has the following technical and geometrical parameters as shown in Table 1. Table 1. The specifications of the laser welding cell 5. Conclusion The laser as economical and flexible tool has established a solid ground in industrial manufacturing area. Specially at welding BIW (Body In White) in automobile industry, the importance of it has been increased due to the technological characteristics such as high process speed, slim seam and good capability of automation and so on. For application of laser welding technique, welding principle and influential factors were investigated based on the analysis of laser welding processes. With that, the main process
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Laser Welding Part 10 pot

LASER WELDING PART 10 POT

with tag points in a virtual environment. The robot program is accomplished based on these information by using GSL (Graphic Simulation Language). After fully examining the accessibility of optic head to all stitches, the collisions with equipments such as jig etc., the welding parameters for the secure of quality, the applicability of sensor to tracing welding path and the operation sequences for preventing from distortion of parts, the program is generated to execute the events offered from the sequence diagram. Three types of the proposed configuration of cell are evaluated through the simulation of laser welding for the side panel with the generated program. The evaluation regarding to technology is done in terms of cycle time related to productivity, minimization shortest moving distance, automation degree, flexibility, available space and possibility of modular system adapting to change of manufacturing environment and so on. From the organization and economy point of view, the terms of expansion ability, control logic, interface between stations and investment and operating cost are chosen for the evaluation. As the result of evaluation, the cell configuration having the parallel arrangement of two robots is selected as optimal due to high score in the load balancing of each robot(the cycle time of each robot is 47.1 sec and 48 sec) and the minimal area required for implementation. The total cycle time for welding the side panel is also saved 3 sec compared to two another cell configurations. In addition, the selected cell has the following technical and geometrical parameters as shown in Table 1. Table 1. The specifications of the laser welding cell 5. Conclusion The laser as economical and flexible tool has established a solid ground in industrial manufacturing area. Specially at welding BIW (Body In White) in automobile industry, the importance of it has been increased due to the technological characteristics such as high process speed, slim seam and good capability of automation and so on. For application of laser welding technique, welding principle and influential factors were investigated based on the analysis of laser welding processes. With that, the main process
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Báo cáo hóa học: " Scalable synthesis of aligned carbon nanotubes bundles using green natural precursor: neem oil" doc

BÁO CÁO HÓA HỌC: " SCALABLE SYNTHESIS OF ALIGNED CARBON NANOTUBES BUNDLES USING GREEN NATURAL PRECURSOR: NEEM OIL" DOC

NANO EXPRESS Open AccessScalable synthesis of aligned carbon nanotubesbundles using green natural precursor: neem oilRajesh Kumar, Radhey Shyam Tiwari*, Onkar Nath SrivastavaAbstractPractical application of aligned carbon nanotubes (ACNTs) would have to be determined by a matter of itseconomical and large-scale preparation. In this study, neem oil (also named Margoaa oil, extracted from the seedsof the neem–Azadirachta indic a ) was used as carbon source to fabricate the bundles of ACNTs. ACNTs hav e beensynthesized by spray pyrolysis of neem oil and ferrocene mixture at 825°C. The major components of neem oil arehydrocarbon with less amount of oxygen, which provided the precursor species in spray pyrolysis growth of CNTs.The bundles of ACNTs have been grown directly inside the quartz tube. The as-grown ACNTs have beencharacterized through Raman spectroscopy, scanning and transmission electron microscopic (SEM/TEM) techniques.SEM images reveal that the bundles of ACNTs are densely packed and are of several microns in length. High-resolution TEM analysis reveals these nanotubes to be multi-walled CNTs. These multi-walled CNTs were found tohave inner diameter between 15 and 30 nm. It was found that present technique gives high yield with highdensity of bundles of ACNTs.IntroductionAdvanced carbonaceous materials have drawn greatattention throughout the world because of their particu-lar microstructur es, unique properties, and great poten-tial applications in many fields. Several carbon speciessuch as methane, acetylene, benzene, xylene, toluene,etc., have been used as a carb on feedstock to synthesizeCNTs [1-7]. These carbon precursors are related to fos-sil fuels which may not be sufficiently available in nearfuture; so in order to develop a more competitive car-bon material, it is necessary to consider devel oping car-bonaceous materials from the natural resource.Recently, there have been reports on the use of natural
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Báo cáo khoa học: Inactive forms of the catalytic subunit of protein kinase A are expressed in the brain of higher primates potx

BÁO CÁO KHOA HỌC INACTIVE FORMS OF THE CATALYTIC SUBUNIT OF PROTEIN KINASE A ARE EXPRESSED IN THE BRAIN OF HIGHER PRIMATES POTX

CN3D software, version 4.1 (NationalCentre for Biotechnology Information, Bethesda, MD, USA). (B) Expression and catalytic activities of Cb1, Cb1D4, Cb3ab and Cb3abD4. Cellextracts of 239T cells, either mock transfected or transfected with expression vectors for Cb1, Cb1D4, Cb3ab and Cb3abD4, were analysedby immunoblotting using a pan-C antibody (upper panel). Immunoreactive PKA C subunits of approximately 40 kDa are clearly recognized inCb1 and Cb3ab transfected cells (lanes 2 and 4) whereas a 35 kDa band is recognized in the CbD4 transfected cells (lanes 3 and 5). Appar-ent molecular masses are indicated by arrows. The same cell extracts were monitored for PKA-specific kinase activity using c-[32P]ATP andthe PKA substrates kemptide (middle panel) and histone (lower panel). Relative kinase activities were compared with PKA activity in mocktransfected cells and are presented as the mean ± SEM from three representative experiments. (C) 239T cells were co-transfected with aCRE-luciferase reporter plasmid, a b-galactosidase control plasmid and one of the following expression vectors: Cb1, Cb1D4, Cb3ab andCb3abD4. Mock samples were transfected with the CRE-luciferase reporter plasmid and b-galactosidase control plasmid only. Cell lysateswere analyzed for C subunit expression levels by immunoblotting using a pan-C antibody (upper panel). A 40 kDa immunoreactive band isclearly recognized in Cb1 and Cb3ab transfected cells (lanes 2 and 4). A 35 kDa immunoreactive band is detected in lanes 3 and 5. Arrowsindicate apparent molecular masses. The cell lysates were monitored for luciferase activity (lower panel). The relative levels of luciferaseactivity were compared with the activity in mock transfected cells and are presented as the mean ± SEM from three representative experi-ments with luciferase activity adjusted according to b-galactosidase-indicated transfection efficiency.Formation of novel PKA C subunits by exon skipping A. C. V. Larsen et al.256 FEBS Journal 275 (2008) 250–262 ª 2007 The Authors Journal compilation ª 2007 FEBSsupernatants analyzed for C subunit immunoreactiveproteins. This demonstrated that Cb1 and Cb3ab arereleased into the supernatant fraction after cAMPtreatment (Fig. 7B, lanes 4 and 8) implying that theyare released from the R subunit. This was not the casewith Cb1D4 and Cb3abD4 which remained in the pelletfraction after treatment with saturating concentrationsof cAMP (Fig. 7B, lanes 3 and 6), implying that theirassociation with the R subunit is insensitive to cAMP.Control experiments were performed by immunopre-cipitating with irrelevant IgG (not shown). Taken
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Báo cáo hóa học: "Biocompatible micro-sized cell culture chamber for the detection of nanoparticle-induced IL8 promoter activity on a small cell population" pot

BÁO CÁO HÓA HỌC BIOCOMPATIBLE MICRO SIZED CELL CULTURE CHAMBER FOR THE DETECTION OF NANOPARTICLE INDUCED IL8 PROMOTER ACTIVITY ON A SMALL CELL POPULATION POT

cells in self-assembled multifunctional microfluidic chip prepared withcarbohydrate beads. Micro and Nanosystems 2010, 2:261-268.40. Zhang Z, Perozziello G, Boccazzi P, Sinskey AJ, Geschke O, Jensen KF:Microbioreactors for bioprocess development. JALA 2007, 12:143-151.41. Jin GZ, Kim M, Shin US, Kim HW: Effect of carbon nanotube coating ofaligned nanofibrous polymer scaffolds on the neurite outgrowth of PC-12 cells. Cell Biol Int 2011, 35:741-745, PMID:21332449.42. Waddell RL, Marra KG, Collins KL, Leung JT, Doctor JS: Using PC12 cells toevaluate poly(caprolactone) and collagenous microcarriers forapplications in nerve guide fabrication. Biotechnol Prog 2003,19:1767-1774.43. Liu D, Yi C, Zhang D, Zhang J, Yang M: Inhibition of proliferation anddifferentiation of mesenchymal stem cells by carboxylated carbonnanotubes. ACS Nano 2010, 4:2185-2195.44. Oostingh GJ, Casals E, Italiani P, Colognato R, Stritzinger R, Ponti J, Pfaller T,Kohl Y, Ooms D, Favilli F, Leppens H, Lucchesi D, Rossi F, Nelissen I,Thielecke H, Puntes VF, Duschl A, Boraschi D: Problems and challenges inthe development and validation of human cell-based assays todetermine nanoparticle-induced immunomodulatory effects. Part FibreToxicol 2011, 8:8.45. Casals E, Pfaller T, Duschl A, Oostingh GJ, Puntes V: Time evolution of thenanoparticle protein corona. ACS Nano 2010, 4:3623-3632.46. Diegoli S, Manciulea AL, Begum S, Jones IP, Lead JR, Preece JA: Interactionbetween manufactured gold nanoparticles and naturally occurringorganic macromolecules. Sci Total Environ 2008, 402:51-61.47. Pan Y, Neuss S, Leifert A, Fischler M, Wen F, Simon U, Schmid G,Brandau W, Jahnen-Dechent W: Size-dependent cytotoxicity of goldnanoparticles. Small 2007, 3:1941-1949.48. Davis RR, Lockwood PE, Hobbs DT, Messer RL, Price RJ, Lewis JB, Wataha JC:In vitro biological effects of sodium titanate materials. J Biomed Mater
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