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Sample records for based clinical microscopy

  1. Mobile phone based clinical microscopy for global health applications.

    Directory of Open Access Journals (Sweden)

    David N Breslauer

    Full Text Available Light microscopy provides a simple, cost-effective, and vital method for the diagnosis and screening of hematologic and infectious diseases. In many regions of the world, however, the required equipment is either unavailable or insufficiently portable, and operators may not possess adequate training to make full use of the images obtained. Counterintuitively, these same regions are often well served by mobile phone networks, suggesting the possibility of leveraging portable, camera-enabled mobile phones for diagnostic imaging and telemedicine. Toward this end we have built a mobile phone-mounted light microscope and demonstrated its potential for clinical use by imaging P. falciparum-infected and sickle red blood cells in brightfield and M. tuberculosis-infected sputum samples in fluorescence with LED excitation. In all cases resolution exceeded that necessary to detect blood cell and microorganism morphology, and with the tuberculosis samples we took further advantage of the digitized images to demonstrate automated bacillus counting via image analysis software. We expect such a telemedicine system for global healthcare via mobile phone -- offering inexpensive brightfield and fluorescence microscopy integrated with automated image analysis -- to provide an important tool for disease diagnosis and screening, particularly in the developing world and rural areas where laboratory facilities are scarce but mobile phone infrastructure is extensive.

  2. Clinical specular microscopy

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    Hirst, L.W.; Laing, R.A.

    1987-01-01

    This book provides the general ophthalmologist with a guide to the clinical applications of specular microscopy. Important material is included on laser injury, cataract surgery, corneal transplants, glaucoma, uveitis, and trauma.

  3. Clinical applications of corneal confocal microscopy

    Directory of Open Access Journals (Sweden)

    Mitra Tavakoli

    2008-06-01

    Full Text Available Mitra Tavakoli1, Parwez Hossain2, Rayaz A Malik11Division of Cardiovascular Medicine, University of Manchester and Manchester Royal Infirmary, Manchester, UK; 2University of Southampton, Southampton Eye Unit, Southampton General Hospital, Southampton, UKAbstract: Corneal confocal microscopy is a novel clinical technique for the study of corneal cellular structure. It provides images which are comparable to in-vitro histochemical techniques delineating corneal epithelium, Bowman’s layer, stroma, Descemet’s membrane and the corneal endothelium. Because, corneal confocal microscopy is a non invasive technique for in vivo imaging of the living cornea it has huge clinical potential to investigate numerous corneal diseases. Thus far it has been used in the detection and management of pathologic and infectious conditions, corneal dystrophies and ecstasies, monitoring contact lens induced corneal changes and for pre and post surgical evaluation (PRK, LASIK and LASEK, flap evaluations and Radial Keratotomy, and penetrating keratoplasty. Most recently it has been used as a surrogate for peripheral nerve damage in a variety of peripheral neuropathies and may have potential in acting as a surrogate marker for endothelial abnormalities.Keywords: corneal confocal microscopy, cornea, infective keratitis, corneal dystrophy, neuropathy

  4. CONTENT-BASED AUTOFOCUSING IN AUTOMATED MICROSCOPY

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    Peter Hamm

    2010-11-01

    Full Text Available Autofocusing is the fundamental step when it comes to image acquisition and analysis with automated microscopy devices. Despite all efforts that have been put into developing a reliable autofocus system, recent methods still lack robustness towards different microscope modes and distracting artefacts. This paper presents a novel automated focusing approach that is generally applicable to different microscope modes (bright-field, phase contrast, Differential Interference Contrast (DIC and fluorescence microscopy. The main innovation consists in a Content-based focus search that makes use of a priori knowledge about the observed objects by employing local object features and Boosted Learning. Hence, this method turns away from common autofocus approaches that apply solely whole image frequency measurements to obtain the focus plane. Thus, it is possible to exclude artefacts from being brought into focus calculation as well as locating the in-focus layer of specific microscopic objects.

  5. Quartz tuning fork based microwave impedance microscopy

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    Cui, Yong-Tao; Ma, Eric Yue; Shen, Zhi-Xun

    2016-06-01

    Microwave impedance microscopy (MIM), a near-field microwave scanning probe technique, has become a powerful tool to characterize local electrical responses in solid state samples. We present the design of a new type of MIM sensor based on quartz tuning fork and electrochemically etched thin metal wires. Due to a higher aspect ratio tip and integration with tuning fork, such design achieves comparable MIM performance and enables easy self-sensing topography feedback in situations where the conventional optical feedback mechanism is not available, thus is complementary to microfabricated shielded stripline-type probes. The new design also enables stable differential mode MIM detection and multiple-frequency MIM measurements with a single sensor.

  6. Portable microscopy platform for the clinical and environmental monitoring

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    Wang, Weiming; Yu, Yan; Huang, Hui; Ou, Jinping

    2016-04-01

    Light microscopy can not only address various diagnosis needs such as aquatic parasites and bacteria such as E. coli in water, but also provide a method for the screening of red tide. Traditional microscope based on the smartphone created by adding lens couldn't keep the tradeoff between field-of-view(FOV) and the resolution. In this paper, we demonstrate a non-contact, light and cost-effective microscope platform, that can image highly dense samples with a spatial resolution of ~0.8um over a field-of-view(FOV) of >1mm2. After captured the direct images, we performed the pixel super-resolution algorithm to improve the image resolution and overcome the hardware interference. The system would be a good point-of-care diagnostic solution in resource limited settings. We validated the performance of the system by imaging resolution test targets, the squamous cell cancer(SqCC) and green algae that necessary to detect the squamous carcinoma and red tide

  7. [Mobile phone based wireless microscopy imaging technology].

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    Yuan, Yucheng; Liu, Jing

    2011-03-01

    This article proposes a new device named "Wireless Cellscope" that combining mobile phone and optical microscope together. The established wireless microscope platform consists of mobile phone, network monitor, miniaturized microscope or high resolution microscope etc. A series of conceptual experiments were performed on microscopic observation of ordinary objects and mice tumor tissue slices. It was demonstrated that, the new method could acquire microscopy images via a wireless way, which is spatially independent. With small size and low cost, the device thus developed has rather wide applicability in non-disturbing investigation of cell/tissue culture and long distance observation of dangerous biological sample etc.

  8. Digital differential confocal microscopy based on spatial shift transformation.

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    Liu, J; Wang, Y; Liu, C; Wilson, T; Wang, H; Tan, J

    2014-11-01

    Differential confocal microscopy is a particularly powerful surface profilometry technique in industrial metrology due to its high axial sensitivity and insensitivity to noise. However, the practical implementation of the technique requires the accurate positioning of point detectors in three-dimensions. We describe a simple alternative based on spatial transformation of a through-focus series of images obtained from a homemade beam scanning confocal microscope. This digital differential confocal microscopy approach is described and compared with the traditional Differential confocal microscopy approach. The ease of use of the digital differential confocal microscopy system is illustrated by performing measurements on a 3D standard specimen.

  9. Correlative atomic force microscopy and localization-based super-resolution microscopy: revealing labelling and image reconstruction artefacts.

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    Monserrate, Aitor; Casado, Santiago; Flors, Cristina

    2014-03-17

    Hybrid microscopy: A correlative microscopy tool that combines in situ super-resolution fluorescence microscopy based on single-molecule localization and atomic force microscopy is presented. Direct comparison with high- resolution topography allows the authors to improve fluorescence labeling and image analysis in super-resolution imaging.

  10. [Clinical pathology on the verge of virtual microscopy].

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    Tolonen, Teemu; Näpänkangas, Juha; Isola, Jorma

    2015-01-01

    For more than 100 years, examinations of pathology specimens have relied on the use of the light microscope. The technological progress of the last few years is enabling the digitizing of histologic specimen slides and application of the virtual microscope in diagnostics. Virtual microscopy will facilitate consultation possibilities, and digital image analysis serves to enhance the level of diagnostics. Organizing and monitoring clinicopathological meetings will become easier. Digital archive of histologic specimens and the virtual microscopy network are expected to benefit training and research as well, particularly what applies to the Finnish biobank network which is currently being established.

  11. The clinical application of evidence-based nursing in the biliary microscopy after operation%循证护理在术后胆道镜中的应用

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    艾刚锋; 万东; 毛云高

    2011-01-01

    目的:探讨用循证护理方法解决术后胆道镜常见问题的护理对策及效果.方法:将循证护理实践应用于术后胆道镜患者,解决患者发热、窦道穿孔、胆汁性腹膜炎、胆管出血、恶心、呕吐、腹泻、导管脱出等问题.结果:78例术后胆道镜患者,12例出现腹泻症状,8例轻度恶心、呕吐,7例出现发热,3例引流管脱出,2例轻度胆管出血,无窦道穿孔、胆汁性腹膜炎等严重并发症发生.通过循证护理应用得到及时、得当的护理,全部康复出院.结论:将循证护理应用于术后胆道镜患者,不仅可提高护理质量,有利于患者康复,而且可以丰富护理人员的经验.%Objective : To explore the effect of used evidence - based approach to observe the common problems. Methods : Through the method of evidence -basefl nursing practice, patients with biliary microscopy were solved fever, sinus perforation or bile peritonitis, bile duct bleeding, nausea, vomiting, diarthea, catheter extrusion and other issues. Results:78 patients with postoperative cholangioscopy had no sinus perforation, biliary peritonitis. Drainage tuhe prolapse happened in 3 cases , slight nausea, vomiting happened in 8 cases of and diarrhea happened in 12 cases, 2 patients happened bile duct slight hemorrhage. Through the application of evidence - based nursing ,7 cases of fever got timely and appropriate nursing interventions and all cases recovered and were discharged satisfactory. Conclusions: Evidence - based nursing was the base of clinical nursing. It is not only improve the quality of care henefit to patients, but also got nursing knowledge.

  12. Optimization-based wavefront sensorless adaptive optics for multiphoton microscopy

    NARCIS (Netherlands)

    Antonello, J.; Werkhoven, T. van; Verhaegen, M.; Truong, H.H.; Keller, C.U.; Gerritsen, H.C.

    2014-01-01

    Optical aberrations have detrimental effects in multiphoton microscopy. These effects can be curtailed by implementing model-based wavefront sensorless adaptive optics, which only requires the addition of a wavefront shaping device, such as a deformable mirror (DM) to an existing microscope. The abe

  13. Clinical applications of in vivo fluorescence confocal laser scanning microscopy

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    Oh, Chilhwan; Park, Sangyong; Kim, Junhyung; Ha, Seunghan; Park, Gyuman; Lee, Gunwoo; Lee, Onseok; Chun, Byungseon; Gweon, Daegab

    2008-02-01

    Living skin for basic and clinical research can be evaluated by Confocal Laser Scanning Microscope (CLSM) non-invasively. CLSM imaging system can achieve skin image its native state either "in vivo" or "fresh biopsy (ex vivo)" without fixation, sectioning and staining that is necessary for routine histology. This study examines the potential fluorescent CLSM with a various exogenous fluorescent contrast agent, to provide with more resolution images in skin. In addition, in vivo fluorescent CLSM researchers will be extended a range of potential clinical application. The prototype of our CLSM system has been developed by Prof. Gweon's group. The operating parameters are composed of some units, such as illuminated wavelength 488 nm, argon illumination power up to 20mW on the skin, objective lens, 0.9NA oil immersion, axial resolution 1.0μm, field of view 200μm x 100μm (lateral resolution , 0.3μm). In human volunteer, fluorescein sodium was administrated topically and intradermally. Animal studies were done in GFP transgenic mouse, IRC mouse and pig skin. For imaging of animal skin, fluorescein sodium, acridine orange, and curcumine were used for fluorescein contrast agent. We also used the GFP transgenic mouse for fluorescein CLSM imaging. In intact skin, absorption of fluorescein sodium by individual corneocyte and hair. Intradermal administrated the fluorescein sodium, distinct outline of keratinocyte cell border could be seen. Curcumin is a yellow food dye that has similar fluorescent properties to fluorescein sodium. Acridin Orange can be highlight nuclei in viable keratinocyte. In vivo CLSM of transgenic GFP mouse enable on in vivo, high resolution view of GFP expressing skin tissue. GFP signals are brightest in corneocyte, kertinocyte, hair and eccrine gland. In intact skin, absorption of fluorescein sodium by individual corneocyte and hair. Intradermal administrated the fluorescein sodium, distinct outline of keratinocyte cell border could be seen. In

  14. Automated seeding-based nuclei segmentation in nonlinear optical microscopy.

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    Medyukhina, Anna; Meyer, Tobias; Heuke, Sandro; Vogler, Nadine; Dietzek, Benjamin; Popp, Jürgen

    2013-10-01

    Nonlinear optical (NLO) microscopy based, e.g., on coherent anti-Stokes Raman scattering (CARS) or two-photon-excited fluorescence (TPEF) is a fast label-free imaging technique, with a great potential for biomedical applications. However, NLO microscopy as a diagnostic tool is still in its infancy; there is a lack of robust and durable nuclei segmentation methods capable of accurate image processing in cases of variable image contrast, nuclear density, and type of investigated tissue. Nonetheless, such algorithms specifically adapted to NLO microscopy present one prerequisite for the technology to be routinely used, e.g., in pathology or intraoperatively for surgical guidance. In this paper, we compare the applicability of different seeding and boundary detection methods to NLO microscopic images in order to develop an optimal seeding-based approach capable of accurate segmentation of both TPEF and CARS images. Among different methods, the Laplacian of Gaussian filter showed the best accuracy for the seeding of the image, while a modified seeded watershed segmentation was the most accurate in the task of boundary detection. The resulting combination of these methods followed by the verification of the detected nuclei performs high average sensitivity and specificity when applied to various types of NLO microscopy images.

  15. Adaptive optics in digital micromirror based confocal microscopy

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    Pozzi, P.; Wilding, D.; Soloviev, O.; Vdovin, G.; Verhaegen, M.

    2016-03-01

    This proceeding reports early results in the development of a new technique for adaptive optics in confocal microscopy. The term adaptive optics refers to the branch of optics in which an active element in the optical system is used to correct inhomogeneities in the media through which light propagates. In its most classical form, mostly used in astronomical imaging, adaptive optics is achieved through a closed loop in which the actuators of a deformable mirror are driven by a wavefront sensor. This approach is severely limited in fluorescence microscopy, as the use of a wavefront sensor requires the presence of a bright, point like source in the field of view, a condition rarely satisfied in microscopy samples. Previously reported approaches to adaptive optics in fluorescence microscopy are therefore limited to the inclusion of fluorescent microspheres in the sample, to use as bright stars for wavefront sensors, or time consuming sensorless optimization procedures, requiring several seconds of optimization before the acquisition of a single image. We propose an alternative approach to the problem, implementing sensorless adaptive optics in a Programmable array microscope. A programmable array microscope is a microscope based on a digital micromirror device, in which the single elements of the micromirror act both as point sources and pinholes.

  16. STED super-resolution microscopy of clinical paraffin-embedded human rectal cancer tissue.

    Directory of Open Access Journals (Sweden)

    Peter Ilgen

    Full Text Available Formalin fixed and paraffin-embedded human tissue resected during cancer surgery is indispensable for diagnostic and therapeutic purposes and represents a vast and largely unexploited resource for research. Optical microscopy of such specimen is curtailed by the diffraction-limited resolution of conventional optical microscopy. To overcome this limitation, we used STED super-resolution microscopy enabling optical resolution well below the diffraction barrier. We visualized nanoscale protein distributions in sections of well-annotated paraffin-embedded human rectal cancer tissue stored in a clinical repository. Using antisera against several mitochondrial proteins, STED microscopy revealed distinct sub-mitochondrial protein distributions, suggesting a high level of structural preservation. Analysis of human tissues stored for up to 17 years demonstrated that these samples were still amenable for super-resolution microscopy. STED microscopy of sections of HER2 positive rectal adenocarcinoma revealed details in the surface and intracellular HER2 distribution that were blurred in the corresponding conventional images, demonstrating the potential of super-resolution microscopy to explore the thus far largely untapped nanoscale regime in tissues stored in biorepositories.

  17. STED super-resolution microscopy of clinical paraffin-embedded human rectal cancer tissue.

    Science.gov (United States)

    Ilgen, Peter; Stoldt, Stefan; Conradi, Lena-Christin; Wurm, Christian Andreas; Rüschoff, Josef; Ghadimi, B Michael; Liersch, Torsten; Jakobs, Stefan

    2014-01-01

    Formalin fixed and paraffin-embedded human tissue resected during cancer surgery is indispensable for diagnostic and therapeutic purposes and represents a vast and largely unexploited resource for research. Optical microscopy of such specimen is curtailed by the diffraction-limited resolution of conventional optical microscopy. To overcome this limitation, we used STED super-resolution microscopy enabling optical resolution well below the diffraction barrier. We visualized nanoscale protein distributions in sections of well-annotated paraffin-embedded human rectal cancer tissue stored in a clinical repository. Using antisera against several mitochondrial proteins, STED microscopy revealed distinct sub-mitochondrial protein distributions, suggesting a high level of structural preservation. Analysis of human tissues stored for up to 17 years demonstrated that these samples were still amenable for super-resolution microscopy. STED microscopy of sections of HER2 positive rectal adenocarcinoma revealed details in the surface and intracellular HER2 distribution that were blurred in the corresponding conventional images, demonstrating the potential of super-resolution microscopy to explore the thus far largely untapped nanoscale regime in tissues stored in biorepositories.

  18. Cryogel micromechanics unraveled by atomic force microscopy-based nanoindentation.

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    Welzel, Petra B; Friedrichs, Jens; Grimmer, Milauscha; Vogler, Steffen; Freudenberg, Uwe; Werner, Carsten

    2014-11-01

    Cell-instructive physical characteristics of macroporous scaffolds, developed for tissue engineering applications, often remain difficult to assess. Here, an atomic force microscopy-based nanoindentation approach is adapted to quantify the local mechanical properties of biohybrid glycosaminoglycan-poly(ethylene glycol) cryogels. Resulting from cryoconcentration effects upon gel formation, cryogel struts are observed to feature a higher stiffness compared to the corresponding bulk hydrogel materials. Local Young's moduli, porosity, and integral moduli of the cryogel scaffolds are compared in dependence on gel formation parameters. The results provide valuable insights into the cryogelation process and a base for adjusting physical characteristics of the obtained cryogel scaffolds, which can critically influence the cellular response.

  19. Multidirectional Image Sensing for Microscopy Based on a Rotatable Robot

    Directory of Open Access Journals (Sweden)

    Yajing Shen

    2015-12-01

    Full Text Available Image sensing at a small scale is essentially important in many fields, including microsample observation, defect inspection, material characterization and so on. However, nowadays, multi-directional micro object imaging is still very challenging due to the limited field of view (FOV of microscopes. This paper reports a novel approach for multi-directional image sensing in microscopes by developing a rotatable robot. First, a robot with endless rotation ability is designed and integrated with the microscope. Then, the micro object is aligned to the rotation axis of the robot automatically based on the proposed forward-backward alignment strategy. After that, multi-directional images of the sample can be obtained by rotating the robot within one revolution under the microscope. To demonstrate the versatility of this approach, we view various types of micro samples from multiple directions in both optical microscopy and scanning electron microscopy, and panoramic images of the samples are processed as well. The proposed method paves a new way for the microscopy image sensing, and we believe it could have significant impact in many fields, especially for sample detection, manipulation and characterization at a small scale.

  20. Stokes vector formalism based second harmonic generation microscopy

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    Qiu, Jianjun; Mazumder, Nirmal; Tsai, Han-Ruei; Hu, Chih-Wei; Kao, Fu-Jen

    2012-02-01

    In this study, we have developed a four-channel Stokes vector formalism based second harmonic generation (SHG) microscopy to map and analyze SHG signal. A four-channel Stokesmeter setup is calibrated and integrated into a laser scanning microscope to measure and characterize the SH's corresponding Stokes parameters. We are demonstrating the use of SH and its Stokes parameters to visualize the birefringence and crystalline orientation of KDP and collagen. We believe the developed method can reveal unprecedented information for biomedical and biomaterial studies.

  1. Gabor-based fusion technique for Optical Coherence Microscopy.

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    Rolland, Jannick P; Meemon, Panomsak; Murali, Supraja; Thompson, Kevin P; Lee, Kye-sung

    2010-02-15

    We recently reported on an Optical Coherence Microscopy technique, whose innovation intrinsically builds on a recently reported - 2 microm invariant lateral resolution by design throughout a 2 mm cubic full-field of view - liquid-lens-based dynamic focusing optical probe [Murali et al., Optics Letters 34, 145-147, 2009]. We shall report in this paper on the image acquisition enabled by this optical probe when combined with an automatic data fusion method developed and described here to produce an in-focus high resolution image throughout the imaging depth of the sample. An African frog tadpole (Xenopus laevis) was imaged with the novel probe and the Gabor-based fusion technique, demonstrating subcellular resolution in a 0.5 mm (lateral) x 0.5 mm (axial) without the need, for the first time, for x-y translation stages, depth scanning, high-cost adaptive optics, or manual intervention. In vivo images of human skin are also presented.

  2. Ultramicrosensors based on transition metal hexacyanoferrates for scanning electrochemical microscopy

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    Maria A. Komkova

    2013-10-01

    Full Text Available We report here a way for improving the stability of ultramicroelectrodes (UME based on hexacyanoferrate-modified metals for the detection of hydrogen peroxide. The most stable sensors were obtained by electrochemical deposition of six layers of hexacyanoferrates (HCF, more specifically, an alternating pattern of three layers of Prussian Blue and three layers of Ni–HCF. The microelectrodes modified with mixed layers were continuously monitored in 1 mM hydrogen peroxide and proved to be stable for more than 5 h under these conditions. The mixed layer microelectrodes exhibited a stability which is five times as high as the stability of conventional Prussian Blue-modified UMEs. The sensitivity of the mixed layer sensor was 0.32 A·M−1·cm−2, and the detection limit was 10 µM. The mixed layer-based UMEs were used as sensors in scanning electrochemical microscopy (SECM experiments for imaging of hydrogen peroxide evolution.

  3. Scanning near field microwave microscopy based on an active resonator

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    Qureshi, Naser; Kolokoltsev, Oleg; Ordonez-Romero, Cesar Leonardo

    2014-03-01

    A large number of recent implementations of near field scanning microwave microscopy (NFSMM) have been based on the perturbation of a resonant cavity connected to a sharp scanning probe. In this work we present results from an alternative approach: the perturbation of a microwave source connected to a scanning tip. Based on a yittrium iron garnet (YIG) cavity ring resonator this scanning probe system has a quality factor greater than 106, which allows us to detect very small frequency shifts, which translates to a very high sensitivity in sample impedance measurements. Using a selection of representative semiconductor, metal and biological samples we show how this approach leads to unusually high sensitivity and spatial resolution. Work supported by a grant from PAPIIT, UNAM 104513.

  4. Operational implementation of LED fluorescence microscopy in screening tuberculosis suspects in an urban HIV clinic in Uganda.

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    Heidi Albert

    Full Text Available BACKGROUND: Light emitting diode (LED fluorescence microscopy (FM is an affordable, technology targeted for use in resource-limited settings and recommended for widespread roll-out by the World Health Organization (WHO. We sought to compare the operational performance of three LED FM methods compared to light microscopy in a cohort of HIV-positive tuberculosis (TB suspects at an urban clinic in a high TB burden country. METHODS: Two spot specimens collected from TB suspects were included in the study. Smears were stained using auramine O method and read after blinding by three LED-based FM methods by trained laboratory technicians in the Infectious Diseases Institutelaboratory. Leftover portions of the refrigerated sputum specimens were transported to the FIND Tuberculosis Research Laboratory for Ziehl Neelsen (ZN smear preparation and reading by experienced technologist as well as liquid and solid culture. RESULTS: 174 of 627 (27.8% specimens collected yielded one or more positive mycobacterial cultures. 94.3% (164/174 were M. tuberculosis complex. LED FM was between 7.3-11.0% more sensitive compared to ZN microscopy. Of the 592 specimens examined by all microscopy methods, there was no significant difference in sensitivity between the three LED FM methods. The specificity of the LED FM methods was between 6.1% and 7.7% lower than ZN microscopy (P<0.001, although exclusion of the single poor reader resulted in over 98% specificity for all FM methods. CONCLUSIONS: Laboratory technicians in routine settings can be trained to use FM which is more sensitive than ZN microscopy. Despite rigorous proficiency testing, there were operator-dependent accuracy issues which highlight the critical need for intensive quality assurance procedures during LED FM implementation. The low sensitivity of FM for HIV-positive individuals particularly those with low CD4 T cell counts, will limit the number of additional patients found by LED FM in countries with high

  5. [Clinical forms of acanthamoeba keratitis as viewed from the standpoint of biomicroscopy and confocal microscopy].

    Science.gov (United States)

    Maĭchuk, Iu F; Maĭchuk, D Iu

    2004-01-01

    Clinical cases of 60 patients with acanthamebic keratitis examined by biomicroscopy and of 22 patients largely examined by confocal microscopy are generalized. Acanthamebic keratitis is a slowly progressing infectious lesion of the cornea, which is caused by acanthamebas freely residing in soil and water. Contaminated contact lenses are the key risk factor. The main clinical features of acanthamebic keratitis are defined; they are presence of risk factors; a unilateral lesion in young, healthy and immune-competent persons; a typical clinical pattern of surface keratitis mainly of the ring shape; corneal neuritis without corneal neovascularization but with a severe pain in the eye; and a slow chronic clinical course, i.e. lasting for several weeks and months. Confocal microscopy is the most effective and fast diagnostic tool because it ensures the detection of acanthamebic cysts and trophozoids in all strata of the corneal stroma. The authors isolate, within the clinical course of acanthamebic keratitis, 5 stages; they are surface epithelial keratitis; surface epithelial punctate keratitis; stromal ring-shaped keratitis; ulcerous keratitis; and keratoscleritis.

  6. Two-photon microscopy using fiber-based nanosecond excitation.

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    Karpf, Sebastian; Eibl, Matthias; Sauer, Benjamin; Reinholz, Fred; Hüttmann, Gereon; Huber, Robert

    2016-07-01

    Two-photon excitation fluorescence (TPEF) microscopy is a powerful technique for sensitive tissue imaging at depths of up to 1000 micrometers. However, due to the shallow penetration, for in vivo imaging of internal organs in patients beam delivery by an endoscope is crucial. Until today, this is hindered by linear and non-linear pulse broadening of the femtosecond pulses in the optical fibers of the endoscopes. Here we present an endoscope-ready, fiber-based TPEF microscope, using nanosecond pulses at low repetition rates instead of femtosecond pulses. These nanosecond pulses lack most of the problems connected with femtosecond pulses but are equally suited for TPEF imaging. We derive and demonstrate that at given cw-power the TPEF signal only depends on the duty cycle of the laser source. Due to the higher pulse energy at the same peak power we can also demonstrate single shot two-photon fluorescence lifetime measurements.

  7. Optimisation-based wavefront sensorless adaptive optics for microscopy

    NARCIS (Netherlands)

    Antonello, J.

    2014-01-01

    Microscopy is an essential tool for life sciences. Thanks to the development of confocal and multiphoton microscopy, scientists are able to obtain high-resolution 3D views of biological specimens. Nevertheless, spatial variations in the index of refraction within specimens cause aberrations that deg

  8. Pulse-Shaping-Based Nonlinear Microscopy: Development and Applications

    Science.gov (United States)

    Flynn, Daniel Christopher

    The combination of optical microscopy and ultrafast spectroscopy make the spatial characterization of chemical kinetics on the femtosecond time scale possible. Commercially available octave-spanning Ti:Sapphire oscillators with sub-8 fs pulse durations can drive a multitude of nonlinear transitions across a significant portion of the visible spectrum with minimal average power. Unfortunately, dispersion from microscope objectives broadens pulse durations, decreases temporal resolution and lowers the peak intensities required for driving nonlinear transitions. In this dissertation, pulse shaping is used to compress laser pulses after the microscope objective. By using a binary genetic algorithm, pulse-shapes are designed to enable selective two-photon excitation. The pulse-shapes are demonstrated in two-photon fluorescence of live COS-7 cells expressing GFP-variants mAmetrine and tdTomato. The pulse-shaping approach is applied to a new multiphoton fluorescence resonance energy transfer (FRET) stoichiometry method that quantifies donor and acceptor molecules in complex, as well as the ratio of total donor to acceptor molecules. Compared to conventional multi-photon imaging techniques that require laser tuning or multiple laser systems to selectively excite individual fluorophores, the pulse-shaping approach offers rapid selective multifluorphore imaging at biologically relevant time scales. By splitting the laser beam into two beams and building a second pulse shaper, a pulse-shaping-based pump-probe microscope is developed. The technique offers multiple imaging modalities, such as excited state absorption (ESA), ground state bleach (GSB), and stimulated emission (SE), enhancing contrast of structures via their unique quantum pathways without the addition of contrast agents. Pulse-shaping based pump-probe microscopy is demonstrated for endogenous chemical-contrast imaging of red blood cells. In the second section of this dissertation, ultrafast spectroscopic

  9. The analysis of aging skin based on multiphoton microscopy

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    Wu, Shulian; Li, Hui; Zhang, Xiaoman; Li, Zhifang; Xu, Shufei

    2010-11-01

    Aging is a very important issue not only in dermatology, but also in cosmetic science. Cutaneous aging involves both chronological and photoaging aging process. The chronological aging is induced with the passage of time. And the photoaging skin is the extrinsic aging caused by sun exposure. The aim of this study is to use multiphoton microscopy (MPM) in vivo to assess intrinsic-age-related and photo-age-related difference. The changes of dermal collagen are measured in quantitively. The algorithm that we used automatically produced the transversal dermal map from MPM. Others, the texture of dermis are analyzed by Fourier transform and Gray Level Co-occurrence Matrix. And the object extraction in textured images is proposed based on the method in object edge extraction, and the aim of it is to detect the object hidden in the skin texture in difference aging skin. The result demonstrates that the approach is effective in detecting the object in epidermis and dermis textured image in different aging skin. It could help to further understand the aging mechanism.

  10. An Evaluation of Web-Based Case Studies in Microscopy

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    Susan M. Merkel

    2009-12-01

    Full Text Available It is often difficult to provide students in introductory science courses with opportunities that mimic the investigative learning experience of doing research. This is particularly true in microbiology courses where advanced microscopy techniques are expensive and difficult to do. To that end, we developed three computer-based case studies around real-life scenarios. Our goals were to: (i improve students’ understanding of advanced microscopic techniques, (ii give students practice analyzing and interpreting data, and (iii model a scientific approach to how these techniques are applied to current issues in microbiology. Each case requires students to use references and interpret actual microscopic images, thus giving them a more realistic experience than we could previously provide. We analyzed student learning and perceptions to these case studies. After doing the case studies, students were more able to apply microscopic methods to a realistic problem, thus demonstrating an understanding of how the methods are used. Students appreciated the intellectual challenges presented by having to interpret and analyze actual microscopic images. This approach has allowed us to introduce new areas of content to our course and to stimulate critical thinking skills, a difficult task in a large introductory microbiology course.

  11. Evidence-based clinical practice

    DEFF Research Database (Denmark)

    Gluud, Christian

    2002-01-01

    Evidence-based medicine combines the patient's preferences with clinical experience and the best research evidence. Randomized clinical trials are considered the most valid research design for evaluating health-care interventions. However, empirical research shows that intervention effects may be...

  12. DNA origami-based standards for quantitative fluorescence microscopy.

    Science.gov (United States)

    Schmied, Jürgen J; Raab, Mario; Forthmann, Carsten; Pibiri, Enrico; Wünsch, Bettina; Dammeyer, Thorben; Tinnefeld, Philip

    2014-01-01

    Validating and testing a fluorescence microscope or a microscopy method requires defined samples that can be used as standards. DNA origami is a new tool that provides a framework to place defined numbers of small molecules such as fluorescent dyes or proteins in a programmed geometry with nanometer precision. The flexibility and versatility in the design of DNA origami microscopy standards makes them ideally suited for the broad variety of emerging super-resolution microscopy methods. As DNA origami structures are durable and portable, they can become a universally available specimen to check the everyday functionality of a microscope. The standards are immobilized on a glass slide, and they can be imaged without further preparation and can be stored for up to 6 months. We describe a detailed protocol for the design, production and use of DNA origami microscopy standards, and we introduce a DNA origami rectangle, bundles and a nanopillar as fluorescent nanoscopic rulers. The protocol provides procedures for the design and realization of fluorescent marks on DNA origami structures, their production and purification, quality control, handling, immobilization, measurement and data analysis. The procedure can be completed in 1-2 d.

  13. Superresolution Imaging of Clinical Formalin Fixed Paraffin Embedded Breast Cancer with Single Molecule Localization Microscopy

    Science.gov (United States)

    Creech, Matthew K.; Wang, Jing; Nan, Xiaolin; Gibbs, Summer L.

    2017-01-01

    Millions of archived formalin-fixed, paraffin-embedded (FFPE) specimens contain valuable molecular insight into healthy and diseased states persevered in their native ultrastructure. To diagnose and treat diseases in tissue on the nanoscopic scale, pathology traditionally employs electron microscopy (EM), but this platform has significant limitations including cost and painstaking sample preparation. The invention of single molecule localization microscopy (SMLM) optically overcame the diffraction limit of light to resolve fluorescently labeled molecules on the nanoscale, leading to many exciting biological discoveries. However, applications of SMLM in preserved tissues has been limited. Through adaptation of the immunofluorescence workflow on FFPE sections milled at histological thickness, cellular architecture can now be visualized on the nanoscale using SMLM including individual mitochondria, undulations in the nuclear lamina, and the HER2 receptor on membrane protrusions in human breast cancer specimens. Using astigmatism imaging, these structures can also be resolved in three dimensions to a depth of ~800 nm. These results demonstrate the utility of SMLM in efficiently uncovering ultrastructural information of archived clinical samples, which may offer molecular insights into the physiopathology of tissues to assist in disease diagnosis and treatment using conventional sample preparation methods. PMID:28098202

  14. In vivo reflectance-mode confocal microscopy in clinical dermatology and cosmetology.

    Science.gov (United States)

    González, S; Gilaberte-Calzada, Y

    2008-02-01

    In vivo reflectance confocal microscopy (RCM) is a non-invasive imaging tool that allows real-time visualization of cells and structures in living skin with near histological resolution. RCM has been used for the assessment of benign and malignant lesions, showing great potential for applications in basic skin research and clinical dermatology. RCM also reveals dynamic changes in the skin over time and in response to specific stimuli, like ultraviolet exposure, which makes it a promising tool in cosmetology, as it allows repetitive sampling without biopsy collection, causing no further damage to the areas under investigation. This review summarizes the latest advances in RCM, and its applications in the characterization of both normal and pathological skin.

  15. Fourier ptychographic microscopy for filtration-based circulating tumor cell enumeration and analysis

    Science.gov (United States)

    Williams, Anthony; Chung, Jaebum; Ou, Xiaoze; Zheng, Guoan; Rawal, Siddarth; Ao, Zheng; Datar, Ram; Yang, Changhuei; Cote, Richard

    2014-06-01

    Circulating tumor cells (CTCs) are recognized as a candidate biomarker with strong prognostic and predictive potential in metastatic disease. Filtration-based enrichment technologies have been used for CTC characterization, and our group has previously developed a membrane microfilter device that demonstrates efficacy in model systems and clinical blood samples. However, uneven filtration surfaces make the use of standard microscopic techniques a difficult task, limiting the performance of automated imaging using commercially available technologies. Here, we report the use of Fourier ptychographic microscopy (FPM) to tackle this challenge. Employing this method, we were able to obtain high-resolution color images, including amplitude and phase, of the microfilter samples over large areas. FPM's ability to perform digital refocusing on complex images is particularly useful in this setting as, in contrast to other imaging platforms, we can focus samples on multiple focal planes within the same frame despite surface unevenness. In model systems, FPM demonstrates high image quality, efficiency, and consistency in detection of tumor cells when comparing corresponding microfilter samples to standard microscopy with high correlation (R2=0.99932). Based on these results, we believe that FPM will have important implications for improved, high throughput, filtration-based CTC analysis, and, more generally, image analysis of uneven surfaces.

  16. Quantitative interferometric microscopy cytometer based on regularized optical flow algorithm

    Science.gov (United States)

    Xue, Liang; Vargas, Javier; Wang, Shouyu; Li, Zhenhua; Liu, Fei

    2015-09-01

    Cell detections and analysis are important in various fields, such as medical observations and disease diagnoses. In order to analyze the cell parameters as well as observe the samples directly, in this paper, we present an improved quantitative interferometric microscopy cytometer, which can monitor the quantitative phase distributions of bio-samples and realize cellular parameter statistics. The proposed system is able to recover the phase imaging of biological samples in the expanded field of view via a regularized optical flow demodulation algorithm. This algorithm reconstructs the phase distribution with high accuracy with only two interferograms acquired at different time points simplifying the scanning system. Additionally, the method is totally automatic, and therefore it is convenient for establishing a quantitative phase cytometer. Moreover, the phase retrieval approach is robust against noise and background. Excitingly, red blood cells are readily investigated with the quantitative interferometric microscopy cytometer system.

  17. Structured light sheet fluorescence microscopy based on four beam interference.

    Science.gov (United States)

    Lei, Ming; Zumbusch, Andreas

    2010-08-30

    A 3D structured light sheet microscope using a four-faceted symmetric pyramid is presented. The sample is illuminated by the resulting four beam interference field. This approach combines advantages of standing wave and structured illumination microscopy. Examples of micrographs of fluorescently labeled Chinese hamster ovary (CHO) cells as well as of the compound eyes of drosophila are shown and the optical sectioning ability of our system is demonstrated. The capabilities and the limitations of the scheme are discussed.

  18. Doubling the resolution of spatial-light-modulator-based differential interference contrast microscopy by structured illumination.

    Science.gov (United States)

    Chen, Jianling; Lv, Xiaohua; Zeng, Shaoqun

    2013-09-01

    Recently developed spatial light modulator (SLM)-based differential interference contrast (DIC) microscopy [Opt. Lett. 34, 2988 (2009)] reveals flexibility on the implementation of DIC imaging. However, its numerical aperture (spatial resolution) is limited to maintain sufficient interference contrast, because it requires two beams to interfere. We present a structured illumination (SI) SLM-based DIC microscopy to effectively improve the lateral resolution of the SLM-based DIC microscopy. The SI field is generated and controlled by an adjustable grating displayed on an SLM. The SI SLM-based DIC expands the bandwidth of the coherent transfer function of the SLM-based DIC imaging system, thus improving the spatial resolution. The reconstructed SI SLM-based DIC image exhibits lateral resolution of approximately 208 nm, doubling that of the common SLM-based DIC image (approximately 415 nm). SI SLM-based DIC microscopy has the potential for achieving high-resolution quantitative phase images.

  19. Some issues on atomic force microscopy based surface characterization

    Institute of Scientific and Technical Information of China (English)

    CHEN Yu-hang; HUANG Wen-hao

    2007-01-01

    Influences of tip radius and sampling interval on applying atomic force microscopy(AFM)in quantitative surface evaluations are investigated by numerical simulations and experiments. Several evaluation parameters of surfaces ranging from amplitude to functional parameters are studied. Numerical and experimental results are in good agreements. The accuracy of estimating tip radius on random rough surface with Gaussian distribution of heights using a blind reconstruction method is also discussed theoretically. It is found that the accuracy is greatly depending on the ratio of actual tip radius to rootmean-square (rms) radius of curvature. To obtain an accurate estimation of tip radius under Gaussian rough surface, the ratio has to be larger than 3/2.

  20. Clinical features and in vivo confocal microscopy assessment in 12 patients with ocular cicatricial pemphigoid

    Science.gov (United States)

    Long, Qin; Zuo, Ya-Gang; Yang, Xue; Gao, Ting-Ting; Liu, Jie; Li, Ying

    2016-01-01

    AIM To describe the clinical features and microstructural characteristics assessed by in vivo confocal microscopy (IVCM) in patients with ocular cicatricial pemphigoid (OCP). METHODS A descriptive, uncontrolled case series study. Patients diagnosed with OCP were examined by clinical history, slit-lamp biomicroscopy features and IVCM images. The results of direct immunofluorescence (DIF) biopsies and indirect immunofluorescence (IIF) were also recorded. Local and systemic immunosuppressive therapy were administered and adjusted according to response. RESULTS A total of 12 consecutive OCP patients (7 male, 5 female; mean age 60.42±10.39y) were recruited. All patients exhibited bilateral progressive conjunctival scarring and recurrent chronic conjunctivitis was the most frequent clinical pattern. The mean duration of symptoms prior to diagnosis of OCP was 2.95±2.85y (range: 5mo to 10y). The Foster classification varied from stage I to IV and 20 eyes (83%) were within or greater than Foster stage III on presentation. Two of the 12 patients (17%) demonstrated positive DIF; 3 of the 12 (25%) patients reported positive IIF. The mean duration of the follow-up period was 20.17±11.88mo (range: 6 to 48mo). IVCM showed variable degrees of abnormality in the conjuctiva-cornea and conjuctival scarring was detected in all the involved eyes. Corneal stromal cell activation and dendritic cell infiltration presented as ocular surface inflammation, ocular surface keratinization along with the destroyed Vogt palisades was noted in eyes with potential limbal stem cell deficiency. After treatment, remission of ocular surface inflammation was achieved in all the patients, 18 eyes (75%) remained stable, 6 eyes (25%) had recurrent conjunctivitis and cicatrization in 2 eyes (8%) was progressing. CONCLUSION As an autoimmune disease, OCP manifests as variable degrees of clinical and laboratory abnormalities with both local and systemic immunosuppressive treatment playing important roles

  1. Endoscopic Microscopy

    Science.gov (United States)

    Sokolov, Konstantin; Sung, Kung-Bin; Collier, Tom; Clark, Anne; Arifler, Dizem; Lacy, Alicia; Descour, Michael; Richards-Kortum, Rebecca

    2002-01-01

    In vivo endoscopic optical microscopy provides a tool to assess tissue architecture and morphology with contrast and resolution similar to that provided by standard histopathology – without need for physical tissue removal. In this article, we focus on optical imaging technologies that have the potential to dramatically improve the detection, prevention, and therapy of epithelial cancers. Epithelial pre-cancers and cancers are associated with a variety of morphologic, architectural, and molecular changes, which currently can be assessed only through invasive, painful biopsy. Optical imaging is ideally suited to detecting cancer-related alterations because it can detect biochemical and morphologic alterations with sub-cellular resolution throughout the entire epithelial thickness. Optical techniques can be implemented non-invasively, in real time, and at low cost to survey the tissue surface at risk. Our manuscript focuses primarily on modalities that currently are the most developed: reflectance confocal microscopy (RCM) and optical coherence tomography (OCT). However, recent advances in fluorescence-based endoscopic microscopy also are reviewed briefly. We discuss the basic principles of these emerging technologies and their current and potential applications in early cancer detection. We also present research activities focused on development of exogenous contrast agents that can enhance the morphological features important for cancer detection and that have the potential to allow vital molecular imaging of cancer-related biomarkers. In conclusion, we discuss future improvements to the technology needed to develop robust clinical devices. PMID:14646041

  2. Atomic force microscopy and scanning electron microscopy evaluation of efficacy of scaling and root planing using magnification: A randomized controlled clinical study

    Directory of Open Access Journals (Sweden)

    Ranjana Mohan

    2013-01-01

    Full Text Available Aim: A randomized controlled clinical study was undertaken to evaluate the effectiveness of scaling and root planing (SRP by using Magnifying Loupes (ML and dental operating microscope (DOM. Materials and Methods: A total of 90 human teeth scheduled for extraction from 18 patients aged between 25 and 65 years suffering from generalized chronic severe periodontitis were randomly assigned to three treatment groups. Group 1 consisted SRP performed without using magnification (unaided, Group 2-SRP with ML and Group 3-SRP with DOM. Following extractions, samples were prepared for (i evaluation of surface topography by atomic force microscopy, (ii presence of smear layer, debris by scanning electron microscopy (iii elemental analysis by energy dispersive X-ray analysis. Data was subjected to statistical analysis using analysis of variance, post-hoc (Tukey-HSD and Chi-square test. Results: Statistically significant (P < 0.001 difference was found among the different treatment groups. Group 3 was the best while Group 1 was the least effective technique for SRP. Order of efficacy in terms of the surface was found to be - Palatal < Lingual < Distal ≅ Mesial < Buccal. Efficiency in mandibular to maxillary teeth was found to be significant (P < 0.05, also anterior to posterior teeth (P < 0.05. Conclusion: Magnification tools significantly enhance the efficacy of supragingival and subgingival SRP.

  3. Rapid differentiation between clinically relevant mycobacteria in microscopy positive clinical specimens and mycobacterial isolates by line probe assay

    DEFF Research Database (Denmark)

    Johansen, Isik Somuncu; Lundgren, Bettina H; Thyssen, Jacob Pontoppidan;

    2002-01-01

    The Inno LiPA Mycobacteria assay, based on PCR amplification of the 16-23S rRNA spacer region of Mycobacterium species, has been designed for identification of mycobacteria grown in culture media and discrimination between Mycobacterium tuberculosis complex, M. avium, M. intracellulare, M. kansasii...... of conventional identification using 16S rDNA analysis and biochemical properties. The assay only misidentified one strain, which was found to be M. avium complex instead of M. intracellulare as found by the conventional tests. The assay allows rapid discrimination of the eight most clinically relevant...

  4. Label-free imaging of rat spinal cords based on multiphoton microscopy

    Science.gov (United States)

    Liao, Chenxi; Wang, Zhenyu; Zhou, Linquan; Zhu, Xiaoqin; Liu, Wenge; Chen, Jianxin

    2016-10-01

    As an integral part of the central nervous system, the spinal cord is a communication cable between the body and the brain. It mainly contains neurons, glial cells, nerve fibers and fiber tracts. The recent development of the optical imaging technique allows high-resolution imaging of biological tissues with the great potential for non-invasively looking inside the body. In this work, we evaluate the imaging capacity of multiphoton microscopy (MPM) based on second harmonic generation (SHG) and two-photon excited fluorescence (TPEF) for the cells and extracellular matrix in the spinal cord at molecular level. Rat spinal cord tissues were sectioned and imaged by MPM to demonstrate that MPM is able to show the microstructure including white matter, gray matter, ventral horns, dorsal horns, and axons based on the distinct intrinsic sources in each region of spinal cord. In the high-resolution and high-contrast MPM images, the cell profile can be clearly identified as dark shadows caused by nuclei and encircled by cytoplasm. The nerve fibers in white matter region emitted both SHG and TPEF signals. The multiphoton microscopic imaging technique proves to be a fast and effective tool for label-free imaging spinal cord tissues, based on endogenous signals in biological tissue. It has the potential to extend this optical technique to clinical study, where the rapid and damage-free imaging is needed.

  5. Recent developments in fluorescence-based microscopy applied in biomedical sciences

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The present short review aims to give an overview of the most recent de velopments in fluorescence microscopy and its applications in biomedical science s. Apart from improvements in well-established methods based on conventional fl u orescence microscopy and confocal microscopy (fluorescence in situ hybridisa tion (FISH), tyramide signal amplification (TSA) in immunocytochemistry, new fluorop hores), more recently introduced techniques like fluorescence resonance energy t ransfer (FRET), fluorescence recovery after photobleaching (FRAP), multiphoton m icroscopy and fluorescence correlation spectroscopy (FCS) will be discussed.

  6. Vibrational imaging based on stimulated Raman scattering microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nandakumar, P; Kovalev, A; Volkmer, A [3. Physikalisches Institut, Universitaet Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart (Germany)], E-mail: a.volkmer@physik.uni-stuttgart.de

    2009-03-15

    A stimulated Raman scattering microscope with near-infrared picosecond laser pulses at high repetition rates (76 MHz) and radio-frequency lock-in detection is accomplished. Based on stimulated Raman loss detection, we demonstrate noninvasive point-by-point vibrational mapping of chemical and biological samples with high sensitivity and without the requirement for labeling of the sample with natural or artificial fluorophores. We experimentally demonstrate a major benefit of this technique, which is the capability to respond exclusively to the linear Raman-resonance properties of the sample, thus allowing a direct quantitative interpretation of image contrast in terms of the number density of Raman-active modes.

  7. Vibrational imaging based on stimulated Raman scattering microscopy

    Science.gov (United States)

    Nandakumar, P.; Kovalev, A.; Volkmer, A.

    2009-03-01

    A stimulated Raman scattering microscope with near-infrared picosecond laser pulses at high repetition rates (76 MHz) and radio-frequency lock-in detection is accomplished. Based on stimulated Raman loss detection, we demonstrate noninvasive point-by-point vibrational mapping of chemical and biological samples with high sensitivity and without the requirement for labeling of the sample with natural or artificial fluorophores. We experimentally demonstrate a major benefit of this technique, which is the capability to respond exclusively to the linear Raman-resonance properties of the sample, thus allowing a direct quantitative interpretation of image contrast in terms of the number density of Raman-active modes.

  8. Ion microscopy based on laser-cooled cesium atoms

    Energy Technology Data Exchange (ETDEWEB)

    Viteau, M.; Reveillard, M.; Kime, L.; Rasser, B.; Sudraud, P. [Orsay Physics, TESCAN Orsay, 95 Avenue des Monts Auréliens – ZA Saint-Charles – 13710 Fuveau (France); Bruneau, Y.; Khalili, G.; Pillet, P.; Comparat, D. [Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS Cachan, Bât. 505, 91405 Orsay (France); Guerri, I. [Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy); Fioretti, A., E-mail: andrea.fioretti@ino.it [Istituto Nazionale di Ottica, INO-CNR, U.O.S. ”Adriano Gozzini”, via Moruzzi 1, 56124 Pisa (Italy); Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, CNISM, Sezione di Pisa, 56127 Pisa (Italy); Ciampini, D.; Allegrini, M.; Fuso, F. [Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy); Istituto Nazionale di Ottica, INO-CNR, U.O.S. ”Adriano Gozzini”, via Moruzzi 1, 56124 Pisa (Italy); Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, CNISM, Sezione di Pisa, 56127 Pisa (Italy)

    2016-05-15

    We demonstrate a prototype of a Focused Ion Beam machine based on the ionization of a laser-cooled cesium beam and adapted for imaging and modifying different surfaces in the few-tens nanometer range. Efficient atomic ionization is obtained by laser promoting ground-state atoms into a target excited Rydberg state, then field-ionizing them in an electric field gradient. The method allows obtaining ion currents up to 130 pA. Comparison with the standard direct photo-ionization of the atomic beam shows, in our conditions, a 40-times larger ion yield. Preliminary imaging results at ion energies in the 1–5 keV range are obtained with a resolution around 40 nm, in the present version of the prototype. Our ion beam is expected to be extremely monochromatic, with an energy spread of the order of the eV, offering great prospects for lithography, imaging and surface analysis. - Highlights: • We realize a Focused Ion Beam with an ionic source based on laser cooled cesium atoms. • Ionization involves excitation of the laser cooled atoms to Rydberg states. • We use the cesium FIB system to image different materials. • We use the cesium FIB to produce permanent modifications on surfaces. • In the present configuration, the focused probe size of the cesium FIB prototype is about 300 nm for beam energies in the 2–5 keV range.

  9. Ion microscopy based on laser-cooled cesium atoms.

    Science.gov (United States)

    Viteau, M; Reveillard, M; Kime, L; Rasser, B; Sudraud, P; Bruneau, Y; Khalili, G; Pillet, P; Comparat, D; Guerri, I; Fioretti, A; Ciampini, D; Allegrini, M; Fuso, F

    2016-05-01

    We demonstrate a prototype of a Focused Ion Beam machine based on the ionization of a laser-cooled cesium beam and adapted for imaging and modifying different surfaces in the few-tens nanometer range. Efficient atomic ionization is obtained by laser promoting ground-state atoms into a target excited Rydberg state, then field-ionizing them in an electric field gradient. The method allows obtaining ion currents up to 130pA. Comparison with the standard direct photo-ionization of the atomic beam shows, in our conditions, a 40-times larger ion yield. Preliminary imaging results at ion energies in the 1-5keV range are obtained with a resolution around 40nm, in the present version of the prototype. Our ion beam is expected to be extremely monochromatic, with an energy spread of the order of the eV, offering great prospects for lithography, imaging and surface analysis.

  10. Super-Resolution Scanning Laser Microscopy Based on Virtually Structured Detection.

    Science.gov (United States)

    Zhi, Yanan; Wang, Benquan; Yao, Xincheng

    2015-01-01

    Light microscopy plays a key role in biological studies and medical diagnosis. The spatial resolution of conventional optical microscopes is limited to approximately half the wavelength of the illumination light as a result of the diffraction limit. Several approaches-including confocal microscopy, stimulated emission depletion microscopy, stochastic optical reconstruction microscopy, photoactivated localization microscopy, and structured illumination microscopy-have been established to achieve super-resolution imaging. However, none of these methods is suitable for the super-resolution ophthalmoscopy of retinal structures because of laser safety issues and inevitable eye movements. We recently experimentally validated virtually structured detection (VSD) as an alternative strategy to extend the diffraction limit. Without the complexity of structured illumination, VSD provides an easy, low-cost, and phase artifact-free strategy to achieve super-resolution in scanning laser microscopy. In this article we summarize the basic principles of the VSD method, review our demonstrated single-point and line-scan super-resolution systems, and discuss both technical challenges and the potential of VSD-based instrumentation for super-resolution ophthalmoscopy of the retina.

  11. Clinical cancer diagnosis using optical fiber-delivered coherent anti-stokes ramon scattering microscopy

    Science.gov (United States)

    Gao, Liang

    This thesis describes the development of a combined label-free imaging and analytical strategy for intraoperative characterization of cancer lesions using the coherent anti-Stokes Raman scattering imaging (CARS) technique. A cell morphology-based analytical platform is developed to characterize CARS images and, hence, provide diagnostic information using disease-related pathology features. This strategy is validated for three different applications, including margin detection for radical prostatectomy, differential diagnosis of lung cancer, as well as detection and differentiation of breast cancer subtypes for in situ analysis of margin status during lumpectomy. As the major contribution of this thesis, the developed analytical strategy shows high accuracy and specificity for all three diseases and thus has introduced the CARS imaging technique into the field of human cancer diagnosis, which holds substantial potential for clinical translations. In addition, I have contributed a project aimed at miniaturizing the CARS imaging device into a microendoscope setup through a fiber-delivery strategy. A four-wave-mixing (FWM) background signal, which is caused by simultaneous delivery of the two CARS-generating excitation laser beams, is initially identified. A polarization-based strategy is then introduced and tested for suppression of this FWM noise. The approach shows effective suppression of the FWM signal, both on microscopic and prototype endoscopic setups, indicating the potential of developing a novel microendoscope with a compatible size for clinical use. These positive results show promise for the development of an all-fiber-based, label-free imaging and analytical platform for minimally invasive detection and diagnosis of cancers during surgery or surgical-biopsy, thus improving surgical outcomes and reducing patients' suffering.

  12. Fully automated corneal endothelial morphometry of images captured by clinical specular microscopy

    Science.gov (United States)

    Bucht, Curry; Söderberg, Per; Manneberg, Göran

    2010-02-01

    The corneal endothelium serves as the posterior barrier of the cornea. Factors such as clarity and refractive properties of the cornea are in direct relationship to the quality of the endothelium. The endothelial cell density is considered the most important morphological factor of the corneal endothelium. Pathological conditions and physical trauma may threaten the endothelial cell density to such an extent that the optical property of the cornea and thus clear eyesight is threatened. Diagnosis of the corneal endothelium through morphometry is an important part of several clinical applications. Morphometry of the corneal endothelium is presently carried out by semi automated analysis of pictures captured by a Clinical Specular Microscope (CSM). Because of the occasional need of operator involvement, this process can be tedious, having a negative impact on sampling size. This study was dedicated to the development and use of fully automated analysis of a very large range of images of the corneal endothelium, captured by CSM, using Fourier analysis. Software was developed in the mathematical programming language Matlab. Pictures of the corneal endothelium, captured by CSM, were read into the analysis software. The software automatically performed digital enhancement of the images, normalizing lights and contrasts. The digitally enhanced images of the corneal endothelium were Fourier transformed, using the fast Fourier transform (FFT) and stored as new images. Tools were developed and applied for identification and analysis of relevant characteristics of the Fourier transformed images. The data obtained from each Fourier transformed image was used to calculate the mean cell density of its corresponding corneal endothelium. The calculation was based on well known diffraction theory. Results in form of estimated cell density of the corneal endothelium were obtained, using fully automated analysis software on 292 images captured by CSM. The cell density obtained by the

  13. Real-time analysis and visualization for single-molecule based super-resolution microscopy.

    Directory of Open Access Journals (Sweden)

    Adel Kechkar

    Full Text Available Accurate multidimensional localization of isolated fluorescent emitters is a time consuming process in single-molecule based super-resolution microscopy. We demonstrate a functional method for real-time reconstruction with automatic feedback control, without compromising the localization accuracy. Compatible with high frame rates of EM-CCD cameras, it relies on a wavelet segmentation algorithm, together with a mix of CPU/GPU implementation. A combination with Gaussian fitting allows direct access to 3D localization. Automatic feedback control ensures optimal molecule density throughout the acquisition process. With this method, we significantly improve the efficiency and feasibility of localization-based super-resolution microscopy.

  14. Real-time analysis and visualization for single-molecule based super-resolution microscopy.

    Science.gov (United States)

    Kechkar, Adel; Nair, Deepak; Heilemann, Mike; Choquet, Daniel; Sibarita, Jean-Baptiste

    2013-01-01

    Accurate multidimensional localization of isolated fluorescent emitters is a time consuming process in single-molecule based super-resolution microscopy. We demonstrate a functional method for real-time reconstruction with automatic feedback control, without compromising the localization accuracy. Compatible with high frame rates of EM-CCD cameras, it relies on a wavelet segmentation algorithm, together with a mix of CPU/GPU implementation. A combination with Gaussian fitting allows direct access to 3D localization. Automatic feedback control ensures optimal molecule density throughout the acquisition process. With this method, we significantly improve the efficiency and feasibility of localization-based super-resolution microscopy.

  15. Scanning electron microscopy and transmission electron microscopy study of hot-deformed gamma-TiAl-based alloy microstructure.

    Science.gov (United States)

    Chrapoński, J; Rodak, K

    2006-09-01

    The aim of this work was to assess the changes in the microstructure of hot-deformed specimens made of alloys containing 46-50 at.% Al, 2 at.% Cr and 2 at.% Nb (and alloying additions such as carbon and boron) with the aid of scanning electron microscopy and transmission electron microscopy techniques. After homogenization and heat treatment performed in order to make diverse lamellae thickness, the specimens were compressed at 1000 degrees C. Transmission electron microscopy examinations of specimens after the compression test revealed the presence of heavily deformed areas with a high density of dislocation. Deformation twins were also observed. Dynamically recrystallized grains were revealed. For alloys no. 2 and no. 3, the recovery and recrystallization processes were more extensive than for alloy no. 1.

  16. Atomic Steps with tuning-fork-based noncontact atomic force microscopy

    NARCIS (Netherlands)

    Rensen, W.H.J.; Hulst, van N.F.; Ruiter, A.G.T.; West, P.E.

    1999-01-01

    Tuning forks as tip-sample distance detectors are a promising and versatile alternative to conventional cantilevers with optical beam deflection in noncontact atomic force microscopy (AFM). Both theory and experiments are presented to make a comparison between conventional and tuning-fork-based AFM.

  17. Use of atomic force microscopy to quantify slip irreversibility in a nickel-base superalloy

    Energy Technology Data Exchange (ETDEWEB)

    Risbet, M.; Feaugas, X.; Guillemer-Neel, C.; Clavel, M

    2003-09-15

    Atomic force microscopy was used to study the evolution of surface deformation during cyclic loading in a nickel-base superalloy. Cyclic slip irreversibility has been investigated using quantitative evaluation of extrusion heights and inter-band spacing. This approach is applied to formulate a microscopic crack initiation law, compared to a classical Manson-Coffin relationship.

  18. Nanoscale contact line visualization based on total internal reflection fluorescence microscopy

    NARCIS (Netherlands)

    Franken, M.J.Z.; Poelma, C.; Westerweel, J.

    2013-01-01

    We describe a novel measurement method to study the contact line of a droplet at nanoscale level. The method is based on Total Internal Reflection Fluorescence Microscopy (TIRFM), which uses an evanescent excitation field produced by total internal reflection of light. The evanescent field depends o

  19. Investigation of Amyloid Structures at Nanoscale via AFM based Dynamic Nanomechncial Microscopy

    DEFF Research Database (Denmark)

    Zhang, Shuai

    2014-01-01

    and material research. Among kinds of techniques, Atomic force microscopy (AFM) has the advantages in amyloid study, due to the real-space nano-resolution, the possibilities to characterize in physiological condition, and easy operation without staining requirement. The recent developed AFM based dynamic...

  20. Carbon fibre tips for scanning probe microscopy based on quartz tuning fork force sensors

    Energy Technology Data Exchange (ETDEWEB)

    Castellanos-Gomez, A; Agrait, N; Rubio-Bollinger, G, E-mail: gabino.rubio@uam.es [Departamento de Fisica de la Materia Condensada (C-III), Universidad Autonoma de Madrid, Campus de Cantoblanco, 28049 Madrid (Spain)

    2010-04-09

    We report the fabrication and the characterization of carbon fibre tips for use in combined scanning tunnelling and force microscopy based on piezoelectric quartz tuning fork force sensors. We find that the use of carbon fibre tips results in a minimum impact on the dynamics of quartz tuning fork force sensors, yielding a high quality factor and, consequently, a high force gradient sensitivity. This high force sensitivity, in combination with high electrical conductivity and oxidation resistance of carbon fibre tips, make them very convenient for combined and simultaneous scanning tunnelling microscopy and atomic force microscopy measurements. Interestingly, these tips are quite robust against occasionally occurring tip crashes. An electrochemical fabrication procedure to etch the tips is presented that produces a sub-100-nm apex radius in a reproducible way which can yield high resolution images.

  1. GPU-based computational adaptive optics for volumetric optical coherence microscopy

    Science.gov (United States)

    Tang, Han; Mulligan, Jeffrey A.; Untracht, Gavrielle R.; Zhang, Xihao; Adie, Steven G.

    2016-03-01

    Optical coherence tomography (OCT) is a non-invasive imaging technique that measures reflectance from within biological tissues. Current higher-NA optical coherence microscopy (OCM) technologies with near cellular resolution have limitations on volumetric imaging capabilities due to the trade-offs between resolution vs. depth-of-field and sensitivity to aberrations. Such trade-offs can be addressed using computational adaptive optics (CAO), which corrects aberration computationally for all depths based on the complex optical field measured by OCT. However, due to the large size of datasets plus the computational complexity of CAO and OCT algorithms, it is a challenge to achieve high-resolution 3D-OCM reconstructions at speeds suitable for clinical and research OCM imaging. In recent years, real-time OCT reconstruction incorporating both dispersion and defocus correction has been achieved through parallel computing on graphics processing units (GPUs). We add to these methods by implementing depth-dependent aberration correction for volumetric OCM using plane-by-plane phase deconvolution. Following both defocus and aberration correction, our reconstruction algorithm achieved depth-independent transverse resolution of 2.8 um, equal to the diffraction-limited focal plane resolution. We have translated the CAO algorithm to a CUDA code implementation and tested the speed of the software in real-time using two GPUs - NVIDIA Quadro K600 and Geforce TITAN Z. For a data volume containing 4096×256×256 voxels, our system's processing speed can keep up with the 60 kHz acquisition rate of the line-scan camera, and takes 1.09 seconds to simultaneously update the CAO correction for 3 en face planes at user-selectable depths.

  2. DMD-based LED-illumination super-resolution and optical sectioning microscopy.

    Science.gov (United States)

    Dan, Dan; Lei, Ming; Yao, Baoli; Wang, Wen; Winterhalder, Martin; Zumbusch, Andreas; Qi, Yujiao; Xia, Liang; Yan, Shaohui; Yang, Yanlong; Gao, Peng; Ye, Tong; Zhao, Wei

    2013-01-01

    Super-resolution three-dimensional (3D) optical microscopy has incomparable advantages over other high-resolution microscopic technologies, such as electron microscopy and atomic force microscopy, in the study of biological molecules, pathways and events in live cells and tissues. We present a novel approach of structured illumination microscopy (SIM) by using a digital micromirror device (DMD) for fringe projection and a low-coherence LED light for illumination. The lateral resolution of 90 nm and the optical sectioning depth of 120 μm were achieved. The maximum acquisition speed for 3D imaging in the optical sectioning mode was 1.6×10(7) pixels/second, which was mainly limited by the sensitivity and speed of the CCD camera. In contrast to other SIM techniques, the DMD-based LED-illumination SIM is cost-effective, ease of multi-wavelength switchable and speckle-noise-free. The 2D super-resolution and 3D optical sectioning modalities can be easily switched and applied to either fluorescent or non-fluorescent specimens.

  3. DMD-based LED-illumination Super-resolution and optical sectioning microscopy

    Science.gov (United States)

    Dan, Dan; Lei, Ming; Yao, Baoli; Wang, Wen; Winterhalder, Martin; Zumbusch, Andreas; Qi, Yujiao; Xia, Liang; Yan, Shaohui; Yang, Yanlong; Gao, Peng; Ye, Tong; Zhao, Wei

    2013-01-01

    Super-resolution three-dimensional (3D) optical microscopy has incomparable advantages over other high-resolution microscopic technologies, such as electron microscopy and atomic force microscopy, in the study of biological molecules, pathways and events in live cells and tissues. We present a novel approach of structured illumination microscopy (SIM) by using a digital micromirror device (DMD) for fringe projection and a low-coherence LED light for illumination. The lateral resolution of 90 nm and the optical sectioning depth of 120 μm were achieved. The maximum acquisition speed for 3D imaging in the optical sectioning mode was 1.6×107 pixels/second, which was mainly limited by the sensitivity and speed of the CCD camera. In contrast to other SIM techniques, the DMD-based LED-illumination SIM is cost-effective, ease of multi-wavelength switchable and speckle-noise-free. The 2D super-resolution and 3D optical sectioning modalities can be easily switched and applied to either fluorescent or non-fluorescent specimens.

  4. Molecular recognition imaging using tuning fork-based transverse dynamic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hofer, Manuel; Adamsmaier, Stefan [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Zanten, Thomas S. van [IBEC-Institute for Bioengineering of Catalonia and CIBER-Bbn, Baldiri i Reixac 15-21, Barcelona 08028 (Spain); Chtcheglova, Lilia A. [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Manzo, Carlo [IBEC-Institute for Bioengineering of Catalonia and CIBER-Bbn, Baldiri i Reixac 15-21, Barcelona 08028 (Spain); Duman, Memed [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Mayer, Barbara [Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Institute for Biophysics, University of Linz, Altenbergerstr. 69, 4040 Linz (Austria); Ebner, Andreas [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Institute for Biophysics, University of Linz, Altenbergerstr. 69, 4040 Linz (Austria); Moertelmaier, Manuel; Kada, Gerald [Agilent Technologies Austria GmbH, Aubrunnerweg 11, 4040 Linz (Austria); Garcia-Parajo, Maria F. [IBEC-Institute for Bioengineering of Catalonia and CIBER-Bbn, Baldiri i Reixac 15-21, Barcelona 08028 (Spain); ICREA-Institucio Catalana de Recerca i Estudis Avancats, 08010 Barcelona (Spain); Hinterdorfer, Peter, E-mail: peter.hinterdorfer@jku.at [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Institute for Biophysics, University of Linz, Altenbergerstr. 69, 4040 Linz (Austria); Kienberger, Ferry [Agilent Technologies Austria GmbH, Aubrunnerweg 11, 4040 Linz (Austria)

    2010-05-15

    We demonstrate simultaneous transverse dynamic force microscopy and molecular recognition imaging using tuning forks as piezoelectric sensors. Tapered aluminum-coated glass fibers were chemically functionalized with biotin and anti-lysozyme molecules and attached to one of the prongs of a 32 kHz tuning fork. The lateral oscillation amplitude of the tuning fork was used as feedback signal for topographical imaging of avidin aggregates and lysozyme molecules on mica substrate. The phase difference between the excitation and detection signals of the tuning fork provided molecular recognition between avidin/biotin or lysozyme/anti-lysozyme. Aggregates of avidin and lysozyme molecules appeared as features with heights of 1-4 nm in the topographic images, consistent with single molecule atomic force microscopy imaging. Recognition events between avidin/biotin or lysozyme/anti-lysozyme were detected in the phase image at high signal-to-noise ratio with phase shifts of 1-2{sup o}. Because tapered glass fibers and shear-force microscopy based on tuning forks are commonly used for near-field scanning optical microscopy (NSOM), these results open the door to the exciting possibility of combining optical, topographic and biochemical recognition at the nanometer scale in a single measurement and in liquid conditions.

  5. Live imaging of Tribolium castaneum embryonic development using light-sheet-based fluorescence microscopy.

    Science.gov (United States)

    Strobl, Frederic; Schmitz, Alexander; Stelzer, Ernst H K

    2015-10-01

    Tribolium castaneum has become an important insect model organism for evolutionary developmental biology, genetics and biotechnology. However, few protocols for live fluorescence imaging of Tribolium have been reported, and little image data is available. Here we provide a protocol for recording the development of Tribolium embryos with light-sheet-based fluorescence microscopy. The protocol can be completed in 4-7 d and provides procedural details for: embryo collection, microscope configuration, embryo preparation and mounting, noninvasive live imaging for up to 120 h along multiple directions, retrieval of the live embryo once imaging is completed, and image data processing, for which exemplary data is provided. Stringent quality control criteria for developmental biology studies are also discussed. Light-sheet-based fluorescence microscopy complements existing toolkits used to study Tribolium development, can be adapted to other insect species, and requires no advanced imaging or sample preparation skills.

  6. Accessing the third dimension in localization-based super-resolution microscopy.

    Science.gov (United States)

    Hajj, Bassam; El Beheiry, Mohamed; Izeddin, Ignacio; Darzacq, Xavier; Dahan, Maxime

    2014-08-21

    Only a few years after its inception, localization-based super-resolution microscopy has become widely employed in biological studies. Yet, it is primarily used in two-dimensional imaging and accessing the organization of cellular structures at the nanoscale in three dimensions (3D) still poses important challenges. Here, we review optical and computational techniques that enable the 3D localization of individual emitters and the reconstruction of 3D super-resolution images. These techniques are grouped into three main categories: PSF engineering, multiple plane imaging and interferometric approaches. We provide an overview of their technical implementation as well as commentary on their applicability. Finally, we discuss future trends in 3D localization-based super-resolution microscopy.

  7. Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials

    Directory of Open Access Journals (Sweden)

    Xiaoxing Ke

    2015-07-01

    Full Text Available A major revolution for electron microscopy in the past decade is the introduction of aberration correction, which enables one to increase both the spatial resolution and the energy resolution to the optical limit. Aberration correction has contributed significantly to the imaging at low operating voltages. This is crucial for carbon-based nanomaterials which are sensitive to electron irradiation. The research of carbon nanomaterials and nanohybrids, in particular the fundamental understanding of defects and interfaces, can now be carried out in unprecedented detail by aberration-corrected transmission electron microscopy (AC-TEM. This review discusses new possibilities and limits of AC-TEM at low voltage, including the structural imaging at atomic resolution, in three dimensions and spectroscopic investigation of chemistry and bonding. In situ TEM of carbon-based nanomaterials is discussed and illustrated through recent reports with particular emphasis on the underlying physics of interactions between electrons and carbon atoms.

  8. Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials.

    Science.gov (United States)

    Ke, Xiaoxing; Bittencourt, Carla; Van Tendeloo, Gustaaf

    2015-01-01

    A major revolution for electron microscopy in the past decade is the introduction of aberration correction, which enables one to increase both the spatial resolution and the energy resolution to the optical limit. Aberration correction has contributed significantly to the imaging at low operating voltages. This is crucial for carbon-based nanomaterials which are sensitive to electron irradiation. The research of carbon nanomaterials and nanohybrids, in particular the fundamental understanding of defects and interfaces, can now be carried out in unprecedented detail by aberration-corrected transmission electron microscopy (AC-TEM). This review discusses new possibilities and limits of AC-TEM at low voltage, including the structural imaging at atomic resolution, in three dimensions and spectroscopic investigation of chemistry and bonding. In situ TEM of carbon-based nanomaterials is discussed and illustrated through recent reports with particular emphasis on the underlying physics of interactions between electrons and carbon atoms.

  9. Real-Time analysis and visualization for single-molecule based super-resolution microscopy

    OpenAIRE

    Kechkar, Adel; Nair, Deepak; Heilemann, Mike; Choquet, Daniel; Sibarita, Jean-Baptiste

    2013-01-01

    Accurate multidimensional localization of isolated fluorescent emitters is a time consuming process in single-molecule based super-resolution microscopy. We demonstrate a functional method for real-time reconstruction with automatic feedback control, without compromising the localization accuracy. Compatible with high frame rates of EM-CCD cameras, it relies on a wavelet segmentation algorithm, together with a mix of CPU/GPU implementation. A combination with Gaussian fitting allows direct ac...

  10. Real-Time Analysis and Visualization for Single-Molecule Based Super-Resolution Microscopy

    OpenAIRE

    Kechkar, Adel; Nair, Deepak; Heilemann, Mike; Choquet, Daniel; Sibarita, Jean-Baptiste

    2013-01-01

    Accurate multidimensional localization of isolated fluorescent emitters is a time consuming process in single-molecule based super-resolution microscopy. We demonstrate a functional method for real-time reconstruction with automatic feedback control, without compromising the localization accuracy. Compatible with high frame rates of EM-CCD cameras, it relies on a wavelet segmentation algorithm, together with a mix of CPU/GPU implementation. A combination with Gaussian fitting allows direct ac...

  11. Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials

    OpenAIRE

    Xiaoxing Ke; Carla Bittencourt; Gustaaf Van Tendeloo

    2015-01-01

    A major revolution for electron microscopy in the past decade is the introduction of aberration correction, which enables one to increase both the spatial resolution and the energy resolution to the optical limit. Aberration correction has contributed significantly to the imaging at low operating voltages. This is crucial for carbon-based nanomaterials which are sensitive to electron irradiation. The research of carbon nanomaterials and nanohybrids, in particular the fundamental understanding...

  12. Super-Resolution Scanning Laser Microscopy Based on Virtually Structured Detection

    OpenAIRE

    Zhi, Yanan; Wang, Benquan; Yao, Xincheng

    2015-01-01

    Light microscopy plays a key role in biological studies and medical diagnosis. The spatial resolution of conventional optical microscopes is limited to approximately half the wavelength of the illumination light as a result of the diffraction limit. Several approaches—including confocal microscopy, stimulated emission depletion microscopy, stochastic optical reconstruction microscopy, photoactivated localization microscopy, and structured illumination microscopy—have been established to achie...

  13. Rapid differentiation between clinically relevant mycobacteria in microscopy positive clinical specimens and mycobacterial isolates by line probe assay

    DEFF Research Database (Denmark)

    Johansen, Isik Somuncu; Lundgren, Bettina H; Thyssen, Jacob Pontoppidan;

    2002-01-01

    The Inno LiPA Mycobacteria assay, based on PCR amplification of the 16-23S rRNA spacer region of Mycobacterium species, has been designed for identification of mycobacteria grown in culture media and discrimination between Mycobacterium tuberculosis complex, M. avium, M. intracellulare, M. kansas...

  14. Atomic Force Microscopy Based Nanorobotics Modelling, Simulation, Setup Building and Experiments

    CERN Document Server

    Xie, Hui; Régnier, Stéphane; Sitti, Metin

    2012-01-01

    The atomic force microscope (AFM) has been successfully used to perform nanorobotic manipulation operations on nanoscale entities such as particles, nanotubes, nanowires, nanocrystals, and DNA since 1990s. There have been many progress on modeling, imaging, teleoperated or automated control, human-machine interfacing, instrumentation, and applications of AFM based nanorobotic manipulation systems in literature. This book aims to include all of such state-of-the-art progress in an organized, structured, and detailed manner as a reference book and also potentially a textbook in nanorobotics and any other nanoscale dynamics, systems and controls related research and education. Clearly written and well-organized, this text introduces designs and prototypes of the nanorobotic systems in detail with innovative principles of three-dimensional manipulation force microscopy and parallel imaging/manipulation force microscopy.

  15. Origin and compensation of imaging artefacts in localization-based super-resolution microscopy.

    Science.gov (United States)

    Erdélyi, M; Sinkó, J; Kákonyi, R; Kelemen, A; Rees, E; Varga, D; Szabó, G

    2015-10-15

    Interpretation of high resolution images provided by localization-based microscopy techniques is a challenge due to imaging artefacts that can be categorized by their origin. They can be introduced by the optical system, by the studied sample or by the applied algorithms. Some artefacts can be eliminated via precise calibration procedures, others can be reduced only below a certain value. Images studied both theoretically and experimentally are qualified either by pattern specific metrics or by a more general metric based on fluorescence correlation spectroscopy.

  16. Deformation mechanisms of human amnion: Quantitative studies based on second harmonic generation microscopy.

    Science.gov (United States)

    Mauri, Arabella; Ehret, Alexander E; Perrini, Michela; Maake, Caroline; Ochsenbein-Kölble, Nicole; Ehrbar, Martin; Oyen, Michelle L; Mazza, Edoardo

    2015-06-25

    Multiphoton microscopy has proven to be a versatile tool to analyze the three-dimensional microstructure of the fetal membrane and the mechanisms of deformation on the length scale of cells and the collagen network. In the present contribution, dedicated microscopic tools for in situ mechanical characterization of tissue under applied mechanical loads and the related methods for data interpretation are presented with emphasis on new stepwise monotonic uniaxial experiments. The resulting microscopic parameters are consistent with previous ones quantified for cyclic and relaxation tests, underlining the reliability of these techniques. The thickness reduction and the substantial alignment of collagen fiber bundles in the compact and fibroblast layer starting at very small loads are highlighted, which challenges the definition of a reference configuration in terms of a force threshold. The findings presented in this paper intend to inform the development of models towards a better understanding of fetal membrane deformation and failure, and thus of related problems in obstetrics and other clinical conditions.

  17. Large-field-of-view Chip-scale Talbot-grid-based Fluorescence Microscopy

    CERN Document Server

    Pang, Shuo; Kato, Mihoko; Sternberg, Paul W; Yang, Changhuei

    2012-01-01

    The fluorescence microscope is one of the most important tools in modern clinical diagnosis and biological science. However, its expense, size and limited field-of-view (FOV) are becoming bottlenecks in key applications such as large-scale phenotyping and low-resource-setting diagnostics. Here we report a low-cost, compact chip-scale fluorescence-imaging platform, termed the Fluorescence Talbot Microscopy (FTM), which utilizes the Talbot self-imaging effect to enable efficient fluorescence imaging over a large and directly-scalable FOV. The FTM prototype has a resolution of 1.2 microns and an FOV of 3.9 mm x 3.5 mm. We demonstrate the imaging capability of FTM on fluorescently labeled breast cancer cells (SK-BR-3) and HEK cells expressing green fluorescent protein.

  18. Polarization sensitive localization based super-resolution microscopy with a birefringent wedge

    Science.gov (United States)

    Sinkó, József; Gajdos, Tamás; Czvik, Elvira; Szabó, Gábor; Erdélyi, Miklós

    2017-03-01

    A practical method has been presented for polarization sensitive localization based super-resolution microscopy using a birefringent dual wedge. The measurement of the polarization degree at the single molecule level can reveal the chemical and physical properties of the local environment of the fluorescent dye molecule and can hence provide information about the sub-diffraction sized structure of biological samples. Polarization sensitive STORM imaging of the F-Actins proved correlation between the orientation of fluorescent dipoles and the axis of the fibril.

  19. Live cell imaging based on surface plasmon-enhanced fluorescence microscopy using random nanostructures

    Science.gov (United States)

    Oh, Youngjin; Lee, Wonju; Son, Taehwang; Kim, Sook Young; Shin, Jeon-Soo; Kim, Donghyun

    2014-02-01

    Localized surface plasmon enhanced microscopy based on nanoislands of random spatial distribution was demonstrated for imaging live cells and molecular interactions. Nanoislands were produced without lithography by high temperature annealing under various processing conditions. The localization of near-field distribution that is associated with localized surface plasmon on metallic random nanoislands was analyzed theoretically and experimentally in comparison with periodic nanostructures. For experimental validation in live cell imaging, mouse macrophage-like cell line stained with Alexa Fluor 488 was prepared on nanoislands. The results suggest the possibility of attaining the imaging resolution on the order of 80 nm.

  20. Atomic force microscopy based nanoindentation study of onion abaxial epidermis walls in aqueous environment

    Energy Technology Data Exchange (ETDEWEB)

    Xi, Xiaoning; Tittmann, Bernhard [Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Kim, Seong H. [Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2015-01-14

    An atomic force microscopy based nanoindentation method was employed to study how the structure of cellulose microfibril packing and matrix polymers affect elastic modulus of fully hydrated primary plant cell walls. The isolated, single-layered abaxial epidermis cell wall of an onion bulb was used as a test system since the cellulose microfibril packing in this cell wall is known to vary systematically from inside to outside scales and the most abundant matrix polymer, pectin, can easily be altered through simple chemical treatments such as ethylenediaminetetraacetic acid and calcium ions. Experimental results showed that the pectin network variation has significant impacts on the cell wall modulus, and not the cellulose microfibril packing.

  1. LED-FISH: Fluorescence microscopy based on light emitting diodes for the molecular analysis of Her-2/neu oncogene amplification

    Directory of Open Access Journals (Sweden)

    Vollmer Ekkehard

    2008-12-01

    Full Text Available Abstract Light emitting diodes (LED, which are available as small monochromatic light sources with characteristic features such as maximum illumination power combined with minimum energy consumption and extremely long lifespan have already proved as a highly potential low-cost alternative for specific diagnostic applications in clinical medicine such as tuberculosis fluorescence microscopy. Likewise, the most reliable evaluation of Her-2/neu (c-erbB2 gene amplification, which has been established in the last few years for routine diagnosis in clinical pathology as determinant towards Herceptin-based treatment of patients with breast cancer, is based on fluorescence in situ hybridization (FISH and corresponding high priced fluorescence equipment. In order to test the possibility to utilize the advantages of low-cost LED technology on FISH analysis of c-erbB2 gene expression for routine diagnostic purposes, the applicability of a standard bright field Carl Zeiss Axiostar Plus microscope equipped with a Fraen AFTER* LED Fluorescence Microscope Kit for the detection of Her-2/neu gene signals was compared to an advanced Nikon Eclipse 80i fluorescence microscope in combination with a conventional 100W mercury vapor lamp. Both microscopes were fitted with the same Quicam FAST CCD digital camera to unequivocally compare the quality of the captured images. C-erbB2 gene expression was analyzed in 30 different human tissue samples of primary invasive breast cancer, following formalin fixation and subsequent paraffin-embedding. The Her2/neu gene signals (green were identifiable in the tumor cells in all cases and images of equal quality were captured under almost identical conditions by 480 nm (blue LED module equipped standard Axiostar microscope as compared to conventional fluorescence microscopy. In this first attempt, these monochromatic LED elements proved in principle to be suitable for the detection of Her-2/neu gene expression by FISH. Thus, our own

  2. Nanoscale contact line visualization based on Total Internal Reflection Fluorescence Microscopy.

    Science.gov (United States)

    Franken, M J Z; Poelma, C; Westerweel, J

    2013-11-04

    We describe a novel measurement method to study the contact line of a droplet at nanoscale level. The method is based on Total Internal Reflection Fluorescence Microscopy (TIRFM), which uses an evanescent excitation field produced by total internal reflection of light. The evanescent field depends on the angle of the incident light and has an exponential intensity decay, characterized by the penetration depth. The penetration depth is determined by imaging a fluorescent particle probe that is traversed using an Atomic Force Microscopy (AFM) setup. The result confirms the exponential behavior of the evanescent field intensity, and the value of the penetration depth also corresponds with the value predicted based on the optical configuration. By using the intensity distribution of a fluorescent dye and the value for the penetration depth of the evanescent wave, it is possible to reconstruct the interface of a partial wetting droplet. The reconstructed interface based on TIRFM is in good agreement with the interface obtained from two reference measurements: non-disturbing AFM-imaging and conventional contact angle measurement. The latter lacks spatial resolution, while the former is limited to particular droplets. This new non-contact measurement does not suffer from these drawbacks, making it a very useful tool to study the fundamental wetting behavior of both stationary and dynamic interfaces.

  3. Theoretical study of carbon-based tips for scanning tunnelling microscopy.

    Science.gov (United States)

    González, C; Abad, E; Dappe, Y J; Cuevas, J C

    2016-03-11

    Motivated by recent experiments, we present here a detailed theoretical analysis of the use of carbon-based conductive tips in scanning tunnelling microscopy. In particular, we employ ab initio methods based on density functional theory to explore a graphitic, an amorphous carbon and two diamond-like tips for imaging with a scanning tunnelling microscope (STM), and we compare them with standard metallic tips made of gold and tungsten. We investigate the performance of these tips in terms of the corrugation of the STM images acquired when scanning a single graphene sheet. Moreover, we analyse the impact of the tip-sample distance and show that it plays a fundamental role in the resolution and symmetry of the STM images. We also explore in depth how the adsorption of single atoms and molecules in the tip apexes modifies the STM images and demonstrate that, in general, it leads to an improved image resolution. The ensemble of our results provides strong evidence that carbon-based tips can significantly improve the resolution of STM images, as compared to more standard metallic tips, which may open a new line of research in scanning tunnelling microscopy.

  4. Theoretical study of carbon-based tips for scanning tunnelling microscopy

    Science.gov (United States)

    González, C.; Abad, E.; Dappe, Y. J.; Cuevas, J. C.

    2016-03-01

    Motivated by recent experiments, we present here a detailed theoretical analysis of the use of carbon-based conductive tips in scanning tunnelling microscopy. In particular, we employ ab initio methods based on density functional theory to explore a graphitic, an amorphous carbon and two diamond-like tips for imaging with a scanning tunnelling microscope (STM), and we compare them with standard metallic tips made of gold and tungsten. We investigate the performance of these tips in terms of the corrugation of the STM images acquired when scanning a single graphene sheet. Moreover, we analyse the impact of the tip-sample distance and show that it plays a fundamental role in the resolution and symmetry of the STM images. We also explore in depth how the adsorption of single atoms and molecules in the tip apexes modifies the STM images and demonstrate that, in general, it leads to an improved image resolution. The ensemble of our results provides strong evidence that carbon-based tips can significantly improve the resolution of STM images, as compared to more standard metallic tips, which may open a new line of research in scanning tunnelling microscopy.

  5. Evaluating the morphology of erythrocyte population: An approach based on atomic force microscopy and flow cytometry.

    Science.gov (United States)

    Ghosh, Sayari; Chakraborty, Ishita; Chakraborty, Monojit; Mukhopadhyay, Ashis; Mishra, Raghwendra; Sarkar, Debasish

    2016-04-01

    Erythrocyte morphology is gaining importance as a powerful pathological index in identifying the severity of any blood related disease. However, the existing technique of quantitative microscopy is highly time consuming and prone to personalized bias. On the other hand, relatively unexplored, complementary technique based on flow cytometry has not been standardized till date, particularly due to the lack of a proper morphological scoring scale. In this article, we have presented a new approach to formulate a non-empirical scoring scale based on membrane roughness (R(rms)) data obtained from atomic force microscopy. Subsequently, the respective morphological quantifier of the whole erythrocyte population, commonly known as morphological index, was expressed as a function of highest correlated statistical parameters of scattered signal profiles generated by flow cytometry. Feed forward artificial neural network model with multilayer perceptron architecture was used to develop the intended functional form. High correlation coefficient (R(2) = 0.95), even for model-formulation exclusive samples, clearly indicates the universal validity of the proposed model. Moreover, a direct pathological application of the proposed model has been illustrated in relation to patients, diagnosed to be suffering from a wide variety of cancer.

  6. Compact, cost-effective and field-portable microscope prototype based on MISHELF microscopy

    Science.gov (United States)

    Sanz, Martín; Picazo-Bueno, José Ángel; Granero, Luis; García, Javier; Micó, Vicente

    2017-01-01

    We report on a reduced cost, portable and compact prototype design of lensless holographic microscope with an illumination/detection scheme based on wavelength multiplexing, working with single hologram acquisition and using a fast convergence algorithm for image processing. All together, MISHELF (initials coming from Multi-Illumination Single-Holographic-Exposure Lensless Fresnel) microscopy allows the recording of three Fresnel domain diffraction patterns in a single camera snap-shot incoming from illuminating the sample with three coherent lights at once. Previous implementations have proposed an illumination/detection procedure based on a tuned (illumination wavelengths centered at the maximum sensitivity of the camera detection channels) configuration but here we report on a detuned (non-centered ones) scheme resulting in prototype miniaturization and cost reduction. Thus, MISHELF microscopy in combination with a novel and fast iterative algorithm allows high-resolution (μm range) phase-retrieved (twin image elimination) quantitative phase imaging of dynamic events (video rate recording speed). The performance of this microscope prototype is validated through experiments using both amplitude (USAF resolution test) and complex (live swine sperm cells and flowing microbeads) samples. The proposed method becomes in an alternative instrument improving some capabilities of existing lensless microscopes. PMID:28233829

  7. Compact, cost-effective and field-portable microscope prototype based on MISHELF microscopy

    Science.gov (United States)

    Sanz, Martín; Picazo-Bueno, José Ángel; Granero, Luis; García, Javier; Micó, Vicente

    2017-02-01

    We report on a reduced cost, portable and compact prototype design of lensless holographic microscope with an illumination/detection scheme based on wavelength multiplexing, working with single hologram acquisition and using a fast convergence algorithm for image processing. All together, MISHELF (initials coming from Multi-Illumination Single-Holographic-Exposure Lensless Fresnel) microscopy allows the recording of three Fresnel domain diffraction patterns in a single camera snap-shot incoming from illuminating the sample with three coherent lights at once. Previous implementations have proposed an illumination/detection procedure based on a tuned (illumination wavelengths centered at the maximum sensitivity of the camera detection channels) configuration but here we report on a detuned (non-centered ones) scheme resulting in prototype miniaturization and cost reduction. Thus, MISHELF microscopy in combination with a novel and fast iterative algorithm allows high-resolution (μm range) phase-retrieved (twin image elimination) quantitative phase imaging of dynamic events (video rate recording speed). The performance of this microscope prototype is validated through experiments using both amplitude (USAF resolution test) and complex (live swine sperm cells and flowing microbeads) samples. The proposed method becomes in an alternative instrument improving some capabilities of existing lensless microscopes.

  8. Electron microscopy characterization of some carbon based nanostructures with application in divertors coatings from fusion reactor

    Science.gov (United States)

    Ciupina, V.; Morjan, I.; Lungu, C. P.; Vladoiu, R.; Prodan, G.; Prodan, M.; Zarovschi, V.; Porosnicu, C.; Stanescu, I. M.; Contulov, M.; Mandes, A.; Dinca, V.; Sugiyama, K.

    2011-10-01

    Nanostructured carbon materials have increasingly attracted the interest of the scientific community, because of their fascinating physical properties and potential applications in high-tech devices. In the current ITER design, the tiles made of carbon fiber composites (CFCs) are foreseen for the strike point zone and tungsten (W) for other parts of the divertor region. This choice is a compromise based mainly on experience with individual materials in many different tokamaks. Also Beryllium is the candidate material for the First Wall in ITER. In order to prepare nanostructured carbon-tungsten nanocomposite for the divertor part in fusion applications, the original method thermionic vacuum arc (TVA) was used in two electronic guns configuration. One of the main advantages of this technology is the bombardment of the growing thin film just by the ions of the depositing film. The nanostructured C-W and C-Be films were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). The C-W films were identified as a nanocrystals complex (5 nm average diameter) surrounded by amorphous structures with a strong graphitization tendency, allowing the creating of adherent and wear resistant films. The C-Be films are polycrystalline with mean grain size about 15 nm. The friction coefficients (0.15 - 0.35) of the C-W coatings was decreased more than 3-5 times in comparison with the uncoated substrates proving excellent tribological properties. C-W nanocomposites coatings were designed to have excellent tribological properties while the structure is composed by nanocrystals complex surrounded by amorphous structures with a strong graphitization tendency, allowing the creating of adherent and wear resistant films.&updat

  9. Novel organic dyes for multicolor localization-based super-resolution microscopy.

    Science.gov (United States)

    Lehmann, Martin; Lichtner, Gregor; Klenz, Haider; Schmoranzer, Jan

    2016-01-01

    Precise multicolor single molecule localization-based microscopy (SMLM) requires bright probes with compatible photo-chemical and spectral properties to resolve distinct molecular species at the nanoscale. The accuracy of multicolor SMLM is further challenged by color channel crosstalk and chromatic alignment errors. These constrains limit the applicability of known reversibly switchable organic dyes for optimized multicolor SMLM. Here, we tested 28 commercially available dyes for their suitability to super-resolve a known cellular nanostructure. We identified eight novel dyes in different spectral regimes that enable high quality dSTORM imaging. Among those, the spectrally close dyes CF647 and CF680 comprise an optimal dye pair for spectral demixing-based, registration free multicolor dSTORM with low crosstalk. Combining this dye pair with the separately excited CF568 we performed 3-color dSTORM to image the relative nanoscale distribution of components of the endocytic machinery and the cytoskeleton.

  10. Quantitative interferometric microscopy with two dimensional Hilbert transform based phase retrieval method

    Science.gov (United States)

    Wang, Shouyu; Yan, Keding; Xue, Liang

    2017-01-01

    In order to obtain high contrast images and detailed descriptions of label free samples, quantitative interferometric microscopy combining with phase retrieval is designed to obtain sample phase distributions from fringes. As accuracy and efficiency of recovered phases are affected by phase retrieval methods, thus approaches owning higher precision and faster processing speed are still in demand. Here, two dimensional Hilbert transform based phase retrieval method is adopted in cellular phase imaging, it not only reserves more sample specifics compared to classical fast Fourier transform based method, but also overcomes disadvantages of traditional algorithm according to Hilbert transform which is a one dimensional processing causing phase ambiguities. Both simulations and experiments are provided, proving the proposed phase retrieval approach can acquire quantitative sample phases with high accuracy and fast speed.

  11. Dual tree complex wavelet transform based denoising of optical microscopy images.

    Science.gov (United States)

    Bal, Ufuk

    2012-12-01

    Photon shot noise is the main noise source of optical microscopy images and can be modeled by a Poisson process. Several discrete wavelet transform based methods have been proposed in the literature for denoising images corrupted by Poisson noise. However, the discrete wavelet transform (DWT) has disadvantages such as shift variance, aliasing, and lack of directional selectivity. To overcome these problems, a dual tree complex wavelet transform is used in our proposed denoising algorithm. Our denoising algorithm is based on the assumption that for the Poisson noise case threshold values for wavelet coefficients can be estimated from the approximation coefficients. Our proposed method was compared with one of the state of the art denoising algorithms. Better results were obtained by using the proposed algorithm in terms of image quality metrics. Furthermore, the contrast enhancement effect of the proposed method on collagen fıber images is examined. Our method allows fast and efficient enhancement of images obtained under low light intensity conditions.

  12. DMD-based LED-illumination Super-resolution and optical sectioning microscopy

    OpenAIRE

    Dan, Dan; Ming LEI; Yao, Baoli; Wang, Wen; Winterhalder, Martin; Zumbusch, Andreas; Qi, Yujiao; Xia, Liang; Yan, Shaohui; Yang, Yanlong; Gao, Peng; Ye, Tong; Zhao,Wei

    2013-01-01

    Super-resolution three-dimensional (3D) optical microscopy has incomparable advantages over other high-resolution microscopic technologies, such as electron microscopy and atomic force microscopy, in the study of biological molecules, pathways and events in live cells and tissues. We present a novel approach of structured illumination microscopy (SIM) by using a digital micromirror device (DMD) for fringe projection and a low-coherence LED light for illumination. The lateral resolution of 90 ...

  13. High-speed and high-SNR photoacoustic microscopy based on a galvanometer mirror in non-conducting liquid

    Science.gov (United States)

    Kim, Jin Young; Lee, Changho; Park, Kyungjin; Han, Sangyeob; Kim, Chulhong

    2016-10-01

    Optical-resolution photoacoustic microscopy (OR-PAM), a promising microscopic imaging technique with high ultrasound resolution and superior optical sensitivity, can provide anatomical, functional, and molecular information at scales ranging from the microvasculature to single red blood cells. In particular, real-time OR-PAM imaging with a high signal-to-noise ratio (SNR) is a prerequisite for widespread use in preclinical and clinical applications. Although several technical approaches have been pursued to simultaneously improve the imaging speed and SNR of OR-PAM, they are bulky, complex, not sensitive, and/or not actually real-time. In this paper, we demonstrate a simple and novel OR-PAM technique which is based on a typical galvanometer immersed in non-conducting liquid. Using an opto-ultrasound combiner, this OR-PAM system achieves a high SNR and fast imaging speed. It takes only 2 seconds to acquire a volumetric image with a wide field of view (FOV) of 4 × 8 mm2 along the X and Y axes, respectively. The measured lateral and axial resolutions are 6.0 and 37.7 μm, respectively. Finally, as a demonstration of the system’s capability, we successfully imaged the microvasculature in a mouse ear in vivo. Our new method will contribute substantially to the popularization and commercialization of OR-PAM in various preclinical and clinical applications.

  14. High-speed and high-SNR photoacoustic microscopy based on a galvanometer mirror in non-conducting liquid

    Science.gov (United States)

    Kim, Jin Young; Lee, Changho; Park, Kyungjin; Han, Sangyeob; Kim, Chulhong

    2016-01-01

    Optical-resolution photoacoustic microscopy (OR-PAM), a promising microscopic imaging technique with high ultrasound resolution and superior optical sensitivity, can provide anatomical, functional, and molecular information at scales ranging from the microvasculature to single red blood cells. In particular, real-time OR-PAM imaging with a high signal-to-noise ratio (SNR) is a prerequisite for widespread use in preclinical and clinical applications. Although several technical approaches have been pursued to simultaneously improve the imaging speed and SNR of OR-PAM, they are bulky, complex, not sensitive, and/or not actually real-time. In this paper, we demonstrate a simple and novel OR-PAM technique which is based on a typical galvanometer immersed in non-conducting liquid. Using an opto-ultrasound combiner, this OR-PAM system achieves a high SNR and fast imaging speed. It takes only 2 seconds to acquire a volumetric image with a wide field of view (FOV) of 4 × 8 mm2 along the X and Y axes, respectively. The measured lateral and axial resolutions are 6.0 and 37.7 μm, respectively. Finally, as a demonstration of the system’s capability, we successfully imaged the microvasculature in a mouse ear in vivo. Our new method will contribute substantially to the popularization and commercialization of OR-PAM in various preclinical and clinical applications. PMID:27708379

  15. Web-based virtual microscopy for parasitology: a novel tool for education and quality assurance.

    Directory of Open Access Journals (Sweden)

    Ewert Linder

    Full Text Available BACKGROUND: The basis for correctly assessing the burden of parasitic infections and the effects of interventions relies on a somewhat shaky foundation as long as we do not know how reliable the reported laboratory findings are. Thus virtual microscopy, successfully introduced as a histopathology tool, has been adapted for medical parasitology. METHODOLOGY/PRINCIPAL FINDINGS: Specimens containing parasites in tissues, stools, and blood have been digitized and made accessible as a "webmicroscope for parasitology" (WMP on the Internet (http://www.webmicroscope.net/parasitology.These digitized specimens can be viewed ("navigated" both in the x-axis and the y-axis at the desired magnification by an unrestricted number of individuals simultaneously. For virtual microscopy of specimens containing stool parasites, it was necessary to develop the technique further in order to enable navigation in the z plane (i.e., "focusing". Specimens were therefore scanned and photographed in two or more focal planes. The resulting digitized specimens consist of stacks of laterally "stiched" individual images covering the entire area of the sample photographed at high magnification. The digitized image information (approximately 10 GB uncompressed data per specimen is accessible at data transfer speeds from 2 to 10 Mb/s via a network of five image servers located in different parts of Europe. Image streaming and rapid data transfer to an ordinary personal computer makes web-based virtual microscopy similar to conventional microscopy. CONCLUSION/SIGNIFICANCE: The potential of this novel technique in the field of medical parasitology to share identical parasitological specimens means that we can provide a "gold standard", which can overcome several problems encountered in quality control of diagnostic parasitology. Thus, the WMP may have an impact on the reliability of data, which constitute the basis for our understanding of the vast problem of neglected tropical

  16. Four-wave mixing based light sources for real-world biomedical applications of coherent Raman microscopy

    Science.gov (United States)

    Gottschall, Thomas; Meyer, Tobias; Jauregui, Cesar; Schmitt, Michael; Popp, Jürgen; Limpert, Jens; Tünnermann, Andreas

    2016-03-01

    Stimulated Raman Scattering requires an extremely quiet, widely wavelength tunable laser, which, up to now, is unheard of in fiber lasers. We present a compact and maintenance-free optical parametric oscillator based on degenerate four-wave mixing in a photonic crystal fiber. By employing an all-fiber frequency and repetition rate tunable laser as a seed source, we are able to generate tunable light between 1015 and 1065 nm. After amplification and subsequent conversion in the fiber OPO, signal and idler radiation between 785 and 960 nm and 1177 and 1500 nm may be generated with a repetition rate of 9 MHz. Therefore, we are able to address Raman shifts between 910 and 3030 cm-1. An additional output provides the Stokes radiation at 18 MHz required for the SRS process, which is passively synchronized to the tunable radiation. We measure the relative intensity noise of the Stokes beam at 9 MHz to be -150 dBc enabling high speed SRS imaging with a good signal-to-noise ratio. The combination of FWM based conversion, coupled with all-fiber Yb-based fiber lasers allows for the first turn-key, widely tunable and extremely compact laser systems developed for applications of CRS microscopy in clinics. This source could very well be the missing key instrument that CRS imaging requires for its real world transition.

  17. Next-generation biomarkers based on 100-parameter functional super-resolution microscopy TIS.

    Science.gov (United States)

    Schubert, Walter; Gieseler, Anne; Krusche, Andreas; Serocka, Peter; Hillert, Reyk

    2012-06-15

    Functional super-resolution (fSR) microscopy is based on the automated toponome imaging system (TIS). fSR-TIS provides insight into the myriad of different cellular functionalities by direct imaging of large subcellular protein networks in morphologically intact cells and tissues, referred to as the toponome. By cyclical fluorescence imaging of at least 100 molecular cell components, fSR-TIS overcomes the spectral limitations of fluorescence microscopy, which is the essential condition for the detection of protein network structures in situ/in vivo. The resulting data sets precisely discriminate between cell types, subcellular structures, cell states and diseases (fSR). With up to 16 bits per protein, the power of combinatorial molecular discrimination (PCMD) is at least 2(100) per subcellular data point. It provides the dimensionality necessary to uncover thousands of distinct protein clusters including their subcellular hierarchies controlling protein network topology and function in the one cell or tissue section. Here we review the technology and findings showing that functional protein networks of the cell surface in different cancers encompass the same hierarchical and spatial coding principle, but express cancer-specific toponome codes within that scheme (referred to as TIS codes). Findings suggest that TIS codes, extracted from large-scale toponome data, have the potential to be next-generation biomarkers because of their cell type and disease specificity. This is functionally substantiated by the observation that blocking toponome-specific lead proteins results in disassembly of molecular networks and loss of function.

  18. PScan 1.0: flexible software framework for polygon based multiphoton microscopy

    Science.gov (United States)

    Li, Yongxiao; Lee, Woei Ming

    2016-12-01

    Multiphoton laser scanning microscopes exhibit highly localized nonlinear optical excitation and are powerful instruments for in-vivo deep tissue imaging. Customized multiphoton microscopy has a significantly superior performance for in-vivo imaging because of precise control over the scanning and detection system. To date, there have been several flexible software platforms catered to custom built microscopy systems i.e. ScanImage, HelioScan, MicroManager, that perform at imaging speeds of 30-100fps. In this paper, we describe a flexible software framework for high speed imaging systems capable of operating from 5 fps to 1600 fps. The software is based on the MATLAB image processing toolbox. It has the capability to communicate directly with a high performing imaging card (Matrox Solios eA/XA), thus retaining high speed acquisition. The program is also designed to communicate with LabVIEW and Fiji for instrument control and image processing. Pscan 1.0 can handle high imaging rates and contains sufficient flexibility for users to adapt to their high speed imaging systems.

  19. All-optical optoacoustic microscopy based on probe beam deflection technique

    Directory of Open Access Journals (Sweden)

    Saher M. Maswadi

    2016-09-01

    Full Text Available Optoacoustic (OA microscopy using an all-optical system based on the probe beam deflection technique (PBDT for detection of laser-induced acoustic signals was investigated as an alternative to conventional piezoelectric transducers. PBDT provides a number of advantages for OA microscopy including (i efficient coupling of laser excitation energy to the samples being imaged through the probing laser beam, (ii undistorted coupling of acoustic waves to the detector without the need for separation of the optical and acoustic paths, (iii high sensitivity and (iv ultrawide bandwidth. Because of the unimpeded optical path in PBDT, diffraction-limited lateral resolution can be readily achieved. The sensitivity of the current PBDT sensor of 22 μV/Pa and its noise equivalent pressure (NEP of 11.4 Pa are comparable with these parameters of the optical micro-ring resonator and commercial piezoelectric ultrasonic transducers. Benefits of the present prototype OA microscope were demonstrated by successfully resolving micron-size details in histological sections of cardiac muscle.

  20. Phytoplankton taxonomy based on CHEMTAX and microscopy in the northwestern Black Sea

    Science.gov (United States)

    Eker-Develi, Elif; Berthon, Jean-François; Canuti, Elisabetta; Slabakova, Natalya; Moncheva, Snejana; Shtereva, Galina; Dzhurova, Boryana

    2012-06-01

    Abundance and carbon biomass of different phytoplankton groups obtained by microscopy were compared with taxonomy derived from pigment measurements and CHEMTAX analysis of samples collected in June 2006 in the NW Black Sea. The diatom Chaetoceros curvisetus was dominant in terms of carbon biomass based on cell volume at inshore stations, while the coccolithophore Emiliania huxleyi was prevalent at offshore. Emiliania huxleyi reached bloom abundance of 3.3 × 106 cells L- 1. The chlorophyll a (chl a) concentration within phytoplankton groups as allocated by CHEMTAX was in agreement with microscopy derived carbon biomasses of the taxonomic groups diatoms, dinoflagellates and cryptophytes only. Carbon biomass of less abundant phytoplankton taxa (cyanophytes, euglenophytes and chlorophytes) did not correlate with group-specific chl a. It was not possible to detect E. huxleyi bloom by CHEMTAX analysis probably due to much higher biomass of other species containing 19'-hexanoyloxyfucoxanthin. Nutrient concentrations were generally high in the waters where diatom and dinoflagellates dominated the community but low in the area of E. huxleyi bloom. A good correlation between total carbon biomass of phytoplankton and chl a was found and the estimated C:chl a ratio of phytoplankton varied between 36 and 256 (in average 124 ± 50).

  1. Analysis of acute brain slices by electron microscopy: a correlative light-electron microscopy workflow based on Tokuyasu cryo-sectioning.

    Science.gov (United States)

    Loussert Fonta, Celine; Leis, Andrew; Mathisen, Cliff; Bouvier, David S; Blanchard, Willy; Volterra, Andrea; Lich, Ben; Humbel, Bruno M

    2015-01-01

    Acute brain slices are slices of brain tissue that are kept vital in vitro for further recordings and analyses. This tool is of major importance in neurobiology and allows the study of brain cells such as microglia, astrocytes, neurons and their inter/intracellular communications via ion channels or transporters. In combination with light/fluorescence microscopies, acute brain slices enable the ex vivo analysis of specific cells or groups of cells inside the slice, e.g. astrocytes. To bridge ex vivo knowledge of a cell with its ultrastructure, we developed a correlative microscopy approach for acute brain slices. The workflow begins with sampling of the tissue and precise trimming of a region of interest, which contains GFP-tagged astrocytes that can be visualised by fluorescence microscopy of ultrathin sections. The astrocytes and their surroundings are then analysed by high resolution scanning transmission electron microscopy (STEM). An important aspect of this workflow is the modification of a commercial cryo-ultramicrotome to observe the fluorescent GFP signal during the trimming process. It ensured that sections contained at least one GFP astrocyte. After cryo-sectioning, a map of the GFP-expressing astrocytes is established and transferred to correlation software installed on a focused ion beam scanning electron microscope equipped with a STEM detector. Next, the areas displaying fluorescence are selected for high resolution STEM imaging. An overview area (e.g. a whole mesh of the grid) is imaged with an automated tiling and stitching process. In the final stitched image, the local organisation of the brain tissue can be surveyed or areas of interest can be magnified to observe fine details, e.g. vesicles or gold labels on specific proteins. The robustness of this workflow is contingent on the quality of sample preparation, based on Tokuyasu's protocol. This method results in a reasonable compromise between preservation of morphology and maintenance of

  2. X-ray microscopy using reflection targets based on SEM with tungsten filament

    Science.gov (United States)

    Liu, Junbiao; Ma, Yutian; Zhao, Weixia; Niu, Geng; Chu, Mingzhang; Yin, Bohua; Han, Li; Liu, Baodong

    2016-10-01

    X-ray MicroandNano imaging is developed based on the conventional x-ray tomography, it can not only provide nondestructive testing with higher resolution measurement, but also be used to examine the material or the structure with low atomic number and low density. The source with micro-focal spot size is one of the key components of x-ray MicroandNano imaging. The focused electron beam from SEM bombarding the metal target can generate x-ray with ultra-small size. It is convenient to set up x-ray microscopy based on SEM for laboratory use. This paper describes a new x-ray microscopy using reflection targets based on FEI Quanta600 SEM with tungsten filament. The flat panel detector is placed outside of the vacuum chamber with 300μm thickness Be-window to isolate vacuum from the air. A stage with 3 DOFs is added to adjust the positions of the target, the SEM's sample stage is used to move sample. And the shape of target is designed as cone with 60° half cone angle to get the maximum x-ray dosage. The attenuation coefficient of Bewindow for x-ray is about 25%. Finally, the line pair card is used to evaluate the resolution and the result shows that the resolution of the system can receive less than 750nm, when the acceleration voltage is 30keV, the beam current is 160nA, the SEM working distance is 5mm and the acquisition time of the detector is 60s.

  3. Context based mixture model for cell phase identification in automated fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Zhou Xiaobo

    2007-01-01

    Full Text Available Abstract Background Automated identification of cell cycle phases of individual live cells in a large population captured via automated fluorescence microscopy technique is important for cancer drug discovery and cell cycle studies. Time-lapse fluorescence microscopy images provide an important method to study the cell cycle process under different conditions of perturbation. Existing methods are limited in dealing with such time-lapse data sets while manual analysis is not feasible. This paper presents statistical data analysis and statistical pattern recognition to perform this task. Results The data is generated from Hela H2B GFP cells imaged during a 2-day period with images acquired 15 minutes apart using an automated time-lapse fluorescence microscopy. The patterns are described with four kinds of features, including twelve general features, Haralick texture features, Zernike moment features, and wavelet features. To generate a new set of features with more discriminate power, the commonly used feature reduction techniques are used, which include Principle Component Analysis (PCA, Linear Discriminant Analysis (LDA, Maximum Margin Criterion (MMC, Stepwise Discriminate Analysis based Feature Selection (SDAFS, and Genetic Algorithm based Feature Selection (GAFS. Then, we propose a Context Based Mixture Model (CBMM for dealing with the time-series cell sequence information and compare it to other traditional classifiers: Support Vector Machine (SVM, Neural Network (NN, and K-Nearest Neighbor (KNN. Being a standard practice in machine learning, we systematically compare the performance of a number of common feature reduction techniques and classifiers to select an optimal combination of a feature reduction technique and a classifier. A cellular database containing 100 manually labelled subsequence is built for evaluating the performance of the classifiers. The generalization error is estimated using the cross validation technique. The

  4. The study on the atomic force microscopy base nanoscale electrical discharge machining.

    Science.gov (United States)

    Huang, Jen-Ching; Chen, Chung-Ming

    2012-01-01

    This study proposes an innovative atomic force microscopy (AFM) based nanoscale electrical discharge machining (AFM-based nanoEDM) system which combines an AFM with a self-produced metallic probe and a high-voltage generator to create an atmospheric environment AFM-based nanoEDM system and a deionized water (DI water) environment AFM-based nanoEDM system. This study combines wire-cut processing and electrochemical tip sharpening techniques on a 40-µm thick stainless steel sheet to produce a high conductive AFM probes, the production can withstand high voltage and large current. The tip radius of these probes is approximately 40 nm. A probe test was executed on the AFM using probes to obtain nanoscales morphology of Si wafer surface. The silicon wafer was as a specimen to carry out AFM-base nanoEDM process in atmospheric and DI water environments by AFM-based nanoEDM system. After experiments, the results show that the atmospheric and DI water environment AFM-based nanoEDM systems operate smoothly. From experimental results, it can be found that the electric discharge depth of the silicon wafer at atmospheric environments is a mere 14.54 nm. In a DI water environment, the depth of electric discharge of the silicon wafer can reach 25.4 nm. This indicates that the EDM ability of DI water environment AFM-based nanoEDM system is higher than that of atmospheric environment AFM-based nanoEDM system. After multiple nanoEDM process, the tips become blunt. After applying electrochemical tip sharpening techniques, the tip radius can return to approximately 40 nm. Therefore, AFM probes produced in this study can be reused.

  5. Atomic Force Microscopy-based Cell Nanostructure for Ligand-conjugated Quantum Dot Endocytosis

    Institute of Scientific and Technical Information of China (English)

    Yun-Long PAN; Ji-Ye CAI; Li QIN; Hao WANG

    2006-01-01

    While it has been well demonstrated that quantum dots (QDs) play an important role in biological labeling both in vitro and in vivo,there is no report describing the cellular nanostructure basis of receptor-mediated endocytosis. Here, nanostructure evolution responses to the endocytosis of transferrin force microscopy (AFM). AFM-based nanostructure analysis demonstrated that the Tf-conjugated QDs were specifically and tightly bound to the cell receptors rrelated with the cell membrane receptor-mediated transduction.Consistently, confocal microscopic and flow cytometry results have demonstrated the specificity and the internalization of Tf-QD is linearly related to time. Moreover, while the nanoparticles on the cell membrane increased, the endocytosis was still nanoparticles did not interfere sterically with the binding and function of receptors. Therefore, ligand-conjugated QDs are potentially useful in biological labeling of cells at a nanometer scale.

  6. Structural and dynamical aspects of skin studied by multiphoton excitation fluorescence microscopy-based methods

    DEFF Research Database (Denmark)

    Bloksgaard, Maria; Brewer, Jonathan R.; Bagatolli, Luis

    2013-01-01

    This mini-review reports on applications of particular multiphoton excitation microscopy-based methodologies employed in our laboratory to study skin. These approaches allow in-depth optical sectioning of the tissue, providing spatially resolved information on specific fluorescence probes...... excised skin, including applications of fluctuation correlation spectroscopy on transdermal penetration of liposomes are presented and discussed. The data from the different studies reported reveal the intrinsic heterogeneity of skin and also prove these strategies to be powerful noninvasive tools......-carboxyethyl)-5-(and-6)-carboxyfluorescein) and diffusion coefficients of distinct fluorescence probes (raster imaging correlation spectroscopy) can be obtained from different regions of the tissue. Comparative studies of different tissue strata, but also between equivalent regions of normal and abnormal...

  7. RESEARCH ON A SCANNING NEAR-FIELD MICROSCOPY BASED ON A QUARTZ RESONATOR

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A scanning near-field acoustic microscopy(SNAM) us ed in imaging the topography of precise surfaces is presented. As a micro-force sensor, a non-encapsulated 1 MHz quartz resonator is damped by hydrodynamic fo rces when approaching an object. Thus the oscillating characteristics of the leg of the quartz resonator change. While measuring the decrease of the amplitude o f vibrating, the shape of the object can be obtained. Based on the analyses of t he principle and key parameters of SNAM, a SNAM is exploited. A lateral resoluti on of 0.5 μm and vertical resolution of 2 nm has been achieved in the experimen ts.

  8. SMILE Microscopy : fast and single-plane based super-resolution volume imaging

    CERN Document Server

    Mondal, Partha Pratim

    2016-01-01

    Fast 3D super-resolution imaging is essential for decoding rapidly occurring biological processes. Encoding single molecules to their respective planes enable simultaneous multi-plane super-resolution volume imaging. This saves the data-acquisition time and as a consequence reduce radiation-dose that lead to photobleaching and other undesirable photochemical reactions. Detection and subsequent identification of the locus of individual molecule (both on the focal plane and off-focal planes) holds the key. Experimentally, this is achieved by accurate calibration of system PSF size and its natural spread in off-focal planes using sub-diffraction fluorescent beads. Subsequently the identification and sorting of single molecules that belong to different axial planes is carried out (by setting multiple cut-offs to respective PSFs). Simultaneous Multiplane Imaging based Localization Encoded (SMILE) microscopy technique eliminates the need for multiple z-plane scanning and thereby provides a truly simultaneous multip...

  9. Super-resolution microscopy based on fluorescence emission difference of cylindrical vector beams

    Science.gov (United States)

    Rong, Zihao; Kuang, Cuifang; Fang, Yue; Zhao, Guangyuan; Xu, Yingke; Liu, Xu

    2015-11-01

    We propose a novel fluorescence emission difference microscopy (FED) system based on focusing cylindrical vector beams. In conventional FED, a Gaussian beam and a 0-2π vortex phase plate are used to generate solid and hollow spots. We focus radially polarized and azimuthally polarized cylindrical vector beams to obtain an expanded solid spot and a shrunken hollow spot, taking advantage of the optical properties of cylindrical vector beams to improve the conventional FED performance. Our novel method enhances FED performance because the hollow spot size determines the FED resolution and an expanded solid spot effectively reduces negative side-lobe emergence during image processing. We demonstrate improved performance theoretically and experimentally using an in-house built FED. Our FED achieved resolution of less than λ/4 in test images of 100 nm nanoparticles, better than the confocal image resolution by a factor of approximately 1/3. We also discuss detailed simulation analyses and FED imaging of biological cells.

  10. Pathological process investigation of Jadassohn-Pellizzari anetoderma based on multiphoton microscopy

    Science.gov (United States)

    Chen, Jianxin; Zhao, Jingjun; Yang, Yinghong; Zhuo, Shuangmu; Jiang, Xingshan; Tian, Wei; Ye, Xiaoyin; Lin, Lihang

    2009-08-01

    Multiphoton microscopy based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) was firstly employed to investigate pathological process from the unaffected skin to the erythematous phase and to finally affected skin of Jadassohn-Pellizzari anetoderma. Our study showed that the normal elastic fibers in unaffected skin were almost completely absent in erthematous skin tissue, then replaced by a lot of elastic fibers with granular morphology in affected skin. The obvious change of collagen fibers and occurrence of inflammatory cell infiltration in erthematous tissue suggested that variation of these two components were also main pathogenesis of anetoderma except for deficiency of elastic fibers. Our results give a sight to noninvasively study the pathological process of skin disease and the other disease with tight relation to variation of collagen and elastic fibers in skin dermis and cell in skin epidermis.

  11. Passive microrheology of soft materials with atomic force microscopy: A wavelet-based spectral analysis

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Torres, C.; Streppa, L. [CNRS, UMR5672, Laboratoire de Physique, Ecole Normale Supérieure de Lyon, 46 Allée d' Italie, Université de Lyon, 69007 Lyon (France); Arneodo, A.; Argoul, F. [CNRS, UMR5672, Laboratoire de Physique, Ecole Normale Supérieure de Lyon, 46 Allée d' Italie, Université de Lyon, 69007 Lyon (France); CNRS, UMR5798, Laboratoire Ondes et Matière d' Aquitaine, Université de Bordeaux, 351 Cours de la Libération, 33405 Talence (France); Argoul, P. [Université Paris-Est, Ecole des Ponts ParisTech, SDOA, MAST, IFSTTAR, 14-20 Bd Newton, Cité Descartes, 77420 Champs sur Marne (France)

    2016-01-18

    Compared to active microrheology where a known force or modulation is periodically imposed to a soft material, passive microrheology relies on the spectral analysis of the spontaneous motion of tracers inherent or external to the material. Passive microrheology studies of soft or living materials with atomic force microscopy (AFM) cantilever tips are rather rare because, in the spectral densities, the rheological response of the materials is hardly distinguishable from other sources of random or periodic perturbations. To circumvent this difficulty, we propose here a wavelet-based decomposition of AFM cantilever tip fluctuations and we show that when applying this multi-scale method to soft polymer layers and to living myoblasts, the structural damping exponents of these soft materials can be retrieved.

  12. Characteristics of scar margin dynamic with time based on multiphoton microscopy.

    Science.gov (United States)

    Zhu, Xiaoqin; Zhuo, Shuangmu; Zheng, Liqin; Jiang, Xingshan; Chen, Jianxin; Lin, Bifang

    2011-03-01

    Scar margins dynamic with time were quantitatively characterized using multiphoton microscopy (MPM). 2D large-area and 3D focused images of elastin and collagen at scar margins were obtained to extract quantitative parameters. An obvious boundary was observed at the scar margin, showing altered morphological patterns of elastin and collagen on both sides. Content alteration of elastin and collagen between the two sides of boundary were defined to characterize scar margins from different individuals. The statistical results from 15 normal scar samples strongly demonstrated that content alteration degree of elastin and collagen had decreasing tendency with the increase of patient age or scar duration, consistent with the fact of normal scars regressing spontaneously over time. It indicated that alteration degree can potentially serve as quantitative indicators to examine wound healing and scar progression over time. With the advent of clinical portable multiphoton endoscopes, the MPM technique can be applied in tracking scar formation and progression in vivo by examination of scar margin.

  13. Quantitative nanohistological investigation of scleroderma: an atomic force microscopy-based approach to disease characterization

    Science.gov (United States)

    Strange, Adam P; Aguayo, Sebastian; Ahmed, Tarek; Mordan, Nicola; Stratton, Richard; Porter, Stephen R; Parekh, Susan; Bozec, Laurent

    2017-01-01

    Scleroderma (or systemic sclerosis, SSc) is a disease caused by excess crosslinking of collagen. The skin stiffens and becomes painful, while internally, organ function can be compromised by the less elastic collagen. Diagnosis of SSc is often only possible in advanced cases by which treatment time is limited. A more detailed analysis of SSc may provide better future treatment options and information of disease progression. Recently, the histological stain picrosirius red showing collagen register has been combined with atomic force microscopy (AFM) to study SSc. Skin from healthy individuals and SSc patients was biopsied, stained and studied using AFM. By investigating the crosslinking of collagen at a smaller hierarchical stage, the effects of SSc were more pronounced. Changes in morphology and Young’s elastic modulus were observed and quantified; giving rise to a novel technique, we have termed “quantitative nanohistology”. An increase in nanoscale stiffness in the collagen for SSc compared with healthy individuals was seen by a significant increase in the Young’s modulus profile for the collagen. These markers of stiffer collagen in SSc are similar to the symptoms experienced by patients, giving additional hope that in the future, nanohistology using AFM can be readily applied as a clinical tool, providing detailed information of the state of collagen. PMID:28138238

  14. Time-stretch microscopy on a DVD for high-throughput imaging cell-based assay.

    Science.gov (United States)

    Tang, Anson H L; Yeung, P; Chan, Godfrey C F; Chan, Barbara P; Wong, Kenneth K Y; Tsia, Kevin K

    2017-02-01

    Cell-based assay based on time-stretch imaging is recognized to be well-suited for high-throughput phenotypic screening. However, this ultrafast imaging technique has primarily been limited to suspension-cell assay, leaving a wide range of solid-substrate assay formats uncharted. Moreover, time-stretch imaging is generally restricted to intrinsic biophysical phenotyping, but lacks the biomolecular signatures of the cells. To address these challenges, we develop a spinning time-stretch imaging assay platform based on the functionalized digital versatile disc (DVD). We demonstrate that adherent cell culture and biochemically-specific cell-capture can now be assayed with time-stretch microscopy, thanks to the high-speed DVD spinning motion that naturally enables on-the-fly cellular imaging at an ultrafast line-scan rate of >10MHz. As scanning the whole DVD at such a high speed enables ultra-large field-of-view imaging, it could be favorable for scaling both the assay throughput and content as demanded in many applications, e.g. drug discovery, and rare cancer cell screening.

  15. Drying techniques for the visualisation of agarose-based chromatography media by scanning electron microscopy.

    Science.gov (United States)

    Nweke, Mauryn C; Turmaine, Mark; McCartney, R Graham; Bracewell, Daniel G

    2017-03-01

    The drying of chromatography resins prior to scanning electron microscopy is critical to image resolution and hence understanding of the bead structure at sub-micron level. Achieving suitable drying conditions is especially important with agarose-based chromatography resins, as over-drying may cause artefact formation, bead damage and alterations to ultrastructural properties; and under-drying does not provide sufficient resolution for visualization under SEM. This paper compares and contrasts the effects of two drying techniques, critical point drying and freeze drying, on the morphology of two agarose based resins (MabSelect™/dw ≈85 µm and Capto™ Adhere/dw ≈75 µm) and provides a complete method for both. The results show that critical point drying provides better drying and subsequently clearer ultrastructural visualization of both resins under SEM. Under this protocol both the polymer fibers (thickness ≈20 nm) and the pore sizes (diameter ≈100 nm) are clearly visible. Freeze drying is shown to cause bead damage to both resins, but to different extents. MabSelect resin encounters extensive bead fragmentation, whilst Capto Adhere resin undergoes partial bead disintegration, corresponding with the greater extent of agarose crosslinking and strength of this resin. While freeze drying appears to be the less favorable option for ultrastructural visualization of chromatography resin, it should be noted that the extent of fracturing caused by the freeze drying process may provide some insight into the mechanical properties of agarose-based chromatography media.

  16. Image-based characterization of thrombus formation in time-lapse DIC microscopy.

    Science.gov (United States)

    Brieu, Nicolas; Navab, Nassir; Serbanovic-Canic, Jovana; Ouwehand, Willem H; Stemple, Derek L; Cvejic, Ana; Groher, Martin

    2012-05-01

    The characterization of thrombus formation in time-lapse DIC microscopy is of increased interest for identifying genes which account for atherothrombosis and coronary artery diseases (CADs). In particular, we are interested in large-scale studies on zebrafish, which result in large amount of data, and require automatic processing. In this work, we present an image-based solution for the automatized extraction of parameters quantifying the temporal development of thrombotic plugs. Our system is based on the joint segmentation of thrombotic and aortic regions over time. This task is made difficult by the low contrast and the high dynamic conditions observed in vivo DIC microscopic scenes. Our key idea is to perform this segmentation by distinguishing the different motion patterns in image time series rather than by solving standard image segmentation tasks in each image frame. Thus, we are able to compensate for the poor imaging conditions. We model motion patterns by energies based on the idea of dynamic textures, and regularize the model by two prior energies on the shape of the aortic region and on the topological relationship between the thrombus and the aorta. We demonstrate the performance of our segmentation algorithm by qualitative and quantitative experiments on synthetic examples as well as on real in vivo microscopic sequences.

  17. Recognizing Disjoint Clinical Concepts in Clinical Text Using Machine Learning-based Methods

    OpenAIRE

    Tang, Buzhou; Chen, Qingcai; Wang, Xiaolong; Wu, Yonghui; Zhang, Yaoyun; Jiang, Min; Wang, Jingqi; Xu, Hua

    2015-01-01

    Clinical concept recognition (CCR) is a fundamental task in clinical natural language processing (NLP) field. Almost all current machine learning-based CCR systems can only recognize clinical concepts of consecutive words (called consecutive clinical concepts, CCCs), but can do nothing about clinical concepts of disjoint words (called disjoint clinical concepts, DCCs), which widely exist in clinical text. In this paper, we proposed two novel types of representations for disjoint clinical conc...

  18. The influence of physical and physiological cues on atomic force microscopy-based cell stiffness assessment.

    Directory of Open Access Journals (Sweden)

    Yu-Wei Chiou

    Full Text Available Atomic force microscopy provides a novel technique for differentiating the mechanical properties of various cell types. Cell elasticity is abundantly used to represent the structural strength of cells in different conditions. In this study, we are interested in whether physical or physiological cues affect cell elasticity in Atomic force microscopy (AFM-based assessments. The physical cues include the geometry of the AFM tips, the indenting force and the operating temperature of the AFM. All of these cues show a significant influence on the cell elasticity assessment. Sharp AFM tips create a two-fold increase in the value of the effective Young's modulus (E(eff relative to that of the blunt tips. Higher indenting force at the same loading rate generates higher estimated cell elasticity. Increasing the operation temperature of the AFM leads to decreases in the cell stiffness because the structure of actin filaments becomes disorganized. The physiological cues include the presence of fetal bovine serum or extracellular matrix-coated surfaces, the culture passage number, and the culture density. Both fetal bovine serum and the extracellular matrix are critical for cells to maintain the integrity of actin filaments and consequently exhibit higher elasticity. Unlike primary cells, mouse kidney progenitor cells can be passaged and maintain their morphology and elasticity for a very long period without a senescence phenotype. Finally, cell elasticity increases with increasing culture density only in MDCK epithelial cells. In summary, for researchers who use AFM to assess cell elasticity, our results provide basic and significant information about the suitable selection of physical and physiological cues.

  19. Spectral demixing avoids registration errors and reduces noise in multicolor localization-based super-resolution microscopy

    Science.gov (United States)

    Lampe, André; Tadeus, Georgi; Schmoranzer, Jan

    2015-09-01

    Multicolor single molecule localization-based super-resolution microscopy (SMLM) approaches are challenged by channel crosstalk and errors in multi-channel registration. We recently introduced a spectral demixing-based variant of direct stochastic optical reconstruction microscopy (SD-dSTORM) to perform multicolor SMLM with minimal color crosstalk. Here, we demonstrate that the spectral demixing procedure is inherently free of errors in multicolor registration and therefore does not require multicolor channel alignment. Furthermore, spectral demixing significantly reduces single molecule noise and is applicable to astigmatism-based 3D multicolor imaging achieving 25 nm lateral and 66 nm axial resolution on cellular nanostructures.

  20. Insights into the prominent effect of mahanimbine on Acanthamoeba castellanii: Cell profiling analysis based on microscopy techniques

    Science.gov (United States)

    Hashim, Fatimah; Amin, Nakisah Mat

    2017-02-01

    Mahanimbine (MH), has been shown to have antiamoeba properties. Therefore, the aim of this study was to assess the growth inhibitory mechanisms of MH on Acanthamoeba castellanii, a causative agents for Acanthamoeba keratitis. The IC50 value obtained for MH against A. castellanii was 1.18 µg/ml. Light and scanning electron microscopy observation showed that most cells were in cystic appearance. While transmission electron microscopy observation revealed changes at the ultrastructural level and fluorescence microscopy observation indicated the induction of apoptosis and autophagic activity in the amoeba cytoplasms. In conclusion, MH has very potent anti-amoebic properties on A. castellanii as is shown by cytotoxicity analyses based on microscopy techniques.

  1. Field portable mobile phone based fluorescence microscopy for detection of Giardia lamblia cysts in water samples

    Science.gov (United States)

    Ceylan Koydemir, Hatice; Gorocs, Zoltan; McLeod, Euan; Tseng, Derek; Ozcan, Aydogan

    2015-03-01

    Giardia lamblia is a waterborne parasite that causes an intestinal infection, known as giardiasis, and it is found not only in countries with inadequate sanitation and unsafe water but also streams and lakes of developed countries. Simple, sensitive, and rapid detection of this pathogen is important for monitoring of drinking water. Here we present a cost-effective and field portable mobile-phone based fluorescence microscopy platform designed for automated detection of Giardia lamblia cysts in large volume water samples (i.e., 10 ml) to be used in low-resource field settings. This fluorescence microscope is integrated with a disposable water-sampling cassette, which is based on a flow-through porous polycarbonate membrane and provides a wide surface area for fluorescence imaging and enumeration of the captured Giardia cysts on the membrane. Water sample of interest, containing fluorescently labeled Giardia cysts, is introduced into the absorbent pads that are in contact with the membrane in the cassette by capillary action, which eliminates the need for electrically driven flow for sample processing. Our fluorescence microscope weighs ~170 grams in total and has all the components of a regular microscope, capable of detecting individual fluorescently labeled cysts under light-emitting-diode (LED) based excitation. Including all the sample preparation, labeling and imaging steps, the entire measurement takes less than one hour for a sample volume of 10 ml. This mobile phone based compact and cost-effective fluorescent imaging platform together with its machine learning based cyst counting interface is easy to use and can even work in resource limited and field settings for spatio-temporal monitoring of water quality.

  2. Statistical region based active contour using a fractional entropy descriptor: Application to nuclei cell segmentation in confocal \\ud microscopy images

    OpenAIRE

    Histace, A.; Meziou, B J; Matuszewski, Bogdan; Precioso, F.; Murphy, M F; Carreiras, F

    2013-01-01

    We propose an unsupervised statistical region based active contour approach integrating an original fractional entropy measure for image segmentation with a particular application to single channel actin tagged fluorescence confocal microscopy image segmentation. Following description of statistical based active contour segmentation and the mathematical definition of the proposed fractional entropy descriptor, we demonstrate comparative segmentation results between the proposed approach and s...

  3. Molecular dynamics-based refinement and validation for sub-5 Å cryo-electron microscopy maps

    Science.gov (United States)

    Singharoy, Abhishek; Teo, Ivan; McGreevy, Ryan; Stone, John E; Zhao, Jianhua; Schulten, Klaus

    2016-01-01

    Two structure determination methods, based on the molecular dynamics flexible fitting (MDFF) paradigm, are presented that resolve sub-5 Å cryo-electron microscopy (EM) maps with either single structures or ensembles of such structures. The methods, denoted cascade MDFF and resolution exchange MDFF, sequentially re-refine a search model against a series of maps of progressively higher resolutions, which ends with the original experimental resolution. Application of sequential re-refinement enables MDFF to achieve a radius of convergence of ~25 Å demonstrated with the accurate modeling of β-galactosidase and TRPV1 proteins at 3.2 Å and 3.4 Å resolution, respectively. The MDFF refinements uniquely offer map-model validation and B-factor determination criteria based on the inherent dynamics of the macromolecules studied, captured by means of local root mean square fluctuations. The MDFF tools described are available to researchers through an easy-to-use and cost-effective cloud computing resource on Amazon Web Services. DOI: http://dx.doi.org/10.7554/eLife.16105.001 PMID:27383269

  4. Single-molecule analysis of fluorescent carbon dots towards localization-based super-resolution microscopy

    Science.gov (United States)

    Verma, Navneet C.; Khan, Syamantak; Nandi, Chayan K.

    2016-12-01

    The advancement of high-resolution bioimaging has always been dependent on the discovery of bright and easily available fluorescent probes. Fluorescent carbon nanodots, an interesting class of relatively new nanomaterials, have emerged as a versatile alternative due to their superior optical properties, non-toxicity, cell penetrability and easy routes to synthesis. Although a plethora of reports is available on bioimaging using carbon dots, single-molecule-based super-resolution imaging is rare in the literature. In this study, we have systematically characterized the single-molecule fluorescence of three carbon dots and compared them with a standard fluorescent probe. Each of these carbon dots showed a long-lived dark state in the presence of an electron acceptor. The electron transfer mechanism was investigated in single-molecule as well as in ensemble experiments. The average on-off rate between the fluorescent bright and dark states, which is one of the important parameters for single-molecule localization-based super-resolution microscopy, was measured by changing the laser power. We report that the photon budget and on-off rate of these carbon dots were good enough to achieve single-molecule localization with a precision of ~35 nm.

  5. Low-Temperature Magnetic Force Microscopy on Single Molecule Magnet-Based Microarrays.

    Science.gov (United States)

    Serri, Michele; Mannini, Matteo; Poggini, Lorenzo; Vélez-Fort, Emilio; Cortigiani, Brunetto; Sainctavit, Philippe; Rovai, Donella; Caneschi, Andrea; Sessoli, Roberta

    2017-03-08

    The magnetic properties of some single molecule magnets (SMM) on surfaces can be strongly modified by the molecular packing in nanometric films/aggregates or by interactions with the substrate, which affect the molecular orientation and geometry. Detailed investigations of the magnetism of thin SMM films and nanostructures are necessary for the development of spin-based molecular devices, however this task is challenged by the limited sensitivity of laboratory-based magnetometric techniques and often requires access to synchrotron light sources to perform surface sensitive X-ray magnetic circular dichroism (XMCD) investigations. Here we show that low-temperature magnetic force microscopy is an alternative powerful laboratory tool able to extract the field dependence of the magnetization and to identify areas of in-plane and perpendicular magnetic anisotropy in microarrays of the SMM terbium(III) bis-phthalocyaninato (TbPc2) neutral complex grown as nanosized films on SiO2 and perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA), and this is in agreement with data extracted from nonlocal XMCD measurements performed on homogeneous TbPc2/PTCDA films.

  6. Sparsity-based multi-height phase recovery in holographic microscopy

    Science.gov (United States)

    Rivenson, Yair; Wu, Yichen; Wang, Hongda; Zhang, Yibo; Feizi, Alborz; Ozcan, Aydogan

    2016-11-01

    High-resolution imaging of densely connected samples such as pathology slides using digital in-line holographic microscopy requires the acquisition of several holograms, e.g., at >6-8 different sample-to-sensor distances, to achieve robust phase recovery and coherent imaging of specimen. Reducing the number of these holographic measurements would normally result in reconstruction artifacts and loss of image quality, which would be detrimental especially for biomedical and diagnostics-related applications. Inspired by the fact that most natural images are sparse in some domain, here we introduce a sparsity-based phase reconstruction technique implemented in wavelet domain to achieve at least 2-fold reduction in the number of holographic measurements for coherent imaging of densely connected samples with minimal impact on the reconstructed image quality, quantified using a structural similarity index. We demonstrated the success of this approach by imaging Papanicolaou smears and breast cancer tissue slides over a large field-of-view of ~20 mm2 using 2 in-line holograms that are acquired at different sample-to-sensor distances and processed using sparsity-based multi-height phase recovery. This new phase recovery approach that makes use of sparsity can also be extended to other coherent imaging schemes, involving e.g., multiple illumination angles or wavelengths to increase the throughput and speed of coherent imaging.

  7. Molecular dynamics-based refinement and validation for sub-5 Å cryo-electron microscopy maps.

    Science.gov (United States)

    Singharoy, Abhishek; Teo, Ivan; McGreevy, Ryan; Stone, John E; Zhao, Jianhua; Schulten, Klaus

    2016-07-07

    Two structure determination methods, based on the molecular dynamics flexible fitting (MDFF) paradigm, are presented that resolve sub-5 Å cryo-electron microscopy (EM) maps with either single structures or ensembles of such structures. The methods, denoted cascade MDFF and resolution exchange MDFF, sequentially re-refine a search model against a series of maps of progressively higher resolutions, which ends with the original experimental resolution. Application of sequential re-refinement enables MDFF to achieve a radius of convergence of ~25 Å demonstrated with the accurate modeling of β-galactosidase and TRPV1 proteins at 3.2 Å and 3.4 Å resolution, respectively. The MDFF refinements uniquely offer map-model validation and B-factor determination criteria based on the inherent dynamics of the macromolecules studied, captured by means of local root mean square fluctuations. The MDFF tools described are available to researchers through an easy-to-use and cost-effective cloud computing resource on Amazon Web Services.

  8. A Dual Microscopy-Based Assay To Assess Listeria monocytogenes Cellular Entry and Vacuolar Escape.

    Science.gov (United States)

    Quereda, Juan J; Pizarro-Cerdá, Javier; Balestrino, Damien; Bobard, Alexandre; Danckaert, Anne; Aulner, Nathalie; Shorte, Spencer; Enninga, Jost; Cossart, Pascale

    2015-10-23

    Listeria monocytogenes is a Gram-positive bacterium and a facultative intracellular pathogen that invades mammalian cells, disrupts its internalization vacuole, and proliferates in the host cell cytoplasm. Here, we describe a novel image-based microscopy assay that allows discrimination between cellular entry and vacuolar escape, enabling high-content screening to identify factors specifically involved in these two steps. We first generated L. monocytogenes and Listeria innocua strains expressing a β-lactamase covalently attached to the bacterial cell wall. These strains were then incubated with HeLa cells containing the Förster resonance energy transfer (FRET) probe CCF4 in their cytoplasm. The CCF4 probe was cleaved by the bacterial surface β-lactamase only in cells inoculated with L. monocytogenes but not those inoculated with L. innocua, thereby demonstrating bacterial access to the host cytoplasm. Subsequently, we performed differential immunofluorescence staining to distinguish extracellular versus total bacterial populations in samples that were also analyzed by the FRET-based assay. With this two-step analysis, bacterial entry can be distinguished from vacuolar rupture in a single experiment. Our novel approach represents a powerful tool for identifying factors that determine the intracellular niche of L. monocytogenes.

  9. Quantitative nanohistological investigation of scleroderma: an atomic force microscopy-based approach to disease characterization

    Directory of Open Access Journals (Sweden)

    Strange AP

    2017-01-01

    Full Text Available Adam P Strange,1 Sebastian Aguayo,1 Tarek Ahmed,1 Nicola Mordan,1 Richard Stratton,2 Stephen R Porter,3 Susan Parekh,4 Laurent Bozec1 1Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, 2Centre for Rheumatology and Connective Tissue Diseases, Royal Free Hospital, UCL Medical School, 3UCL Eastman Dental Institute, 4Department of Pediatrics, UCL Eastman Dental Institute, London, UK Abstract: Scleroderma (or systemic sclerosis, SSc is a disease caused by excess crosslinking of collagen. The skin stiffens and becomes painful, while internally, organ function can be compromised by the less elastic collagen. Diagnosis of SSc is often only possible in advanced cases by which treatment time is limited. A more detailed analysis of SSc may provide better future treatment options and information of disease progression. Recently, the histological stain picrosirius red showing collagen register has been combined with atomic force microscopy (AFM to study SSc. Skin from healthy individuals and SSc patients was biopsied, stained and studied using AFM. By investigating the crosslinking of collagen at a smaller hierarchical stage, the effects of SSc were more pronounced. Changes in morphology and Young’s elastic modulus were observed and quantified; giving rise to a novel technique, we have termed “quantitative nanohistology”. An increase in nanoscale stiffness in the collagen for SSc compared with healthy individuals was seen by a significant increase in the Young’s modulus profile for the collagen. These markers of stiffer collagen in SSc are similar to the symptoms experienced by patients, giving additional hope that in the future, nanohistology using AFM can be readily applied as a clinical tool, providing detailed information of the state of collagen. Keywords: rheumatology, adjunct diagnosis, picrosirius red, collagen, nanohistology

  10. High-speed and high-SNR photoacoustic microscopy based on a galvanometer mirror in non-conducting liquid

    OpenAIRE

    Jin Young Kim; Changho Lee; Kyungjin Park; Sangyeob Han; Chulhong Kim

    2016-01-01

    Optical-resolution photoacoustic microscopy (OR-PAM), a promising microscopic imaging technique with high ultrasound resolution and superior optical sensitivity, can provide anatomical, functional, and molecular information at scales ranging from the microvasculature to single red blood cells. In particular, real-time OR-PAM imaging with a high signal-to-noise ratio (SNR) is a prerequisite for widespread use in preclinical and clinical applications. Although several technical approaches have ...

  11. A review of RGB-LED based mixed-color illumination system for machine vision and microscopy

    Science.gov (United States)

    Hou, Lexin; Wang, Hexin; Xu, Min

    2016-09-01

    The theory and application of RGB-LED based mixed-color illumination system for use in machine vision and optical microscopy systems are presented. For machine vision system, relationship of various color sources and output image sharpness is discussed. From the viewpoint of gray scale images, evaluation and optimization methods of optimal illumination for machine vision are concluded. The image quality under monochromatic and mixed color illumination is compared. For optical microscopy system, demand of light source is introduced and design thoughts of RGB-LED based mixed-color illumination system are concluded. The problems need to be solved in this field are pointed out.

  12. Nanomechanical assessment of human and murine collagen fibrils via atomic force microscopy cantilever-based nanoindentation.

    Science.gov (United States)

    Andriotis, Orestis G; Manuyakorn, Wiparat; Zekonyte, Jurgita; Katsamenis, Orestis L; Fabri, Sebastien; Howarth, Peter H; Davies, Donna E; Thurner, Philipp J

    2014-11-01

    The nanomechanical assessment of collagen fibrils via atomic force microscopy (AFM) is of increasing interest within the biomedical research community. In contrast to conventional nanoindentation there exists no common standard for conducting experiments and analysis of data. Currently used analysis approaches vary between studies and validation of quantitative results is usually not performed, which makes comparison of data from different studies difficult. Also there are no recommendations with regards to the maximum indentation depth that should not be exceeded to avoid substrate effects. Here we present a methodology and analysis approach for AFM cantilever-based nanoindentation experiments that allows efficient use of captured data and relying on a reference sample for determination of tip shape. Further we show experimental evidence that maximum indentation depth on collagen fibrils should be lower than 10-15% of the height of the fibril to avoid substrate effects and we show comparisons between our and other approaches used in previous works. While our analysis approach yields similar values for indentation modulus compared to the Oliver-Pharr method we found that Hertzian analysis yielded significantly lower values. Applying our approach we successfully and efficiently indented collagen fibrils from human bronchi, which were about 30 nm in size, considerably smaller compared to collagen fibrils obtained from murine tail-tendon. In addition, derived mechanical parameters of collagen fibrils are in agreement with data previously published. To establish a quantitative validation we compared indentation results from conventional and AFM cantilever-based nanoindentation on polymeric samples with known mechanical properties. Importantly we can show that our approach yields similar results when compared to conventional nanoindentation on polymer samples. Introducing an approach that is reliable, efficient and taking into account the AFM tip shape, we anticipate

  13. Context based support for Clinical Reasoning

    DEFF Research Database (Denmark)

    Vilstrup Pedersen, Klaus

    2004-01-01

    In many areas of the medical domain, the decision process i.e. reasoning, involving health care professionals is distributed, cooperative and complex. Computer based decision support systems has usually been focusing on the outcome of the decision making and treated it as a single task. In this p......In many areas of the medical domain, the decision process i.e. reasoning, involving health care professionals is distributed, cooperative and complex. Computer based decision support systems has usually been focusing on the outcome of the decision making and treated it as a single task....... In this paper a framework for a Clinical Reasoning Knowledge Warehouse (CRKW) is presented, intended to support the reasoning process, by providing the decision participants with an analysis platform that captures and enhances information and knowledge. The CRKW mixes theories and models from Artificial...... Intelligence, Knowledge Management Systems and Business Intelligence to make context sensitive, patient case specific analysis and knowledge management. The knowledge base consists of patient health records, reasoning process information and clinical guidelines. Patient specific information and knowledge...

  14. A confocal microscopy-based atlas of tissue architecture in the tapeworm Hymenolepis diminuta.

    Science.gov (United States)

    Rozario, Tania; Newmark, Phillip A

    2015-11-01

    Tapeworms are pervasive and globally distributed parasites that infect millions of humans and livestock every year, and are the causative agents of two of the 17 neglected tropical diseases prioritized by the World Health Organization. Studies of tapeworm biology and pathology are often encumbered by the complex life cycles of disease-relevant tapeworm species that infect hosts such as foxes, dogs, cattle, pigs, and humans. Thus, studies of laboratory models can help overcome the practical, ethical, and cost-related difficulties faced by tapeworm parasitologists. The rat intestinal tapeworm Hymenolepis diminuta is easily reared in the laboratory and has the potential to enable modern molecular-based experiments that will greatly contribute to our understanding of multiple aspects of tapeworm biology, such as growth and reproduction. As part of our efforts to develop molecular tools for experiments on H. diminuta, we have characterized a battery of lectins, antibodies, and common stains that label different tapeworm tissues and organ structures. Using confocal microscopy, we have assembled an "atlas" of H. diminuta organ architecture that will be a useful resource for helminthologists. The methodologies we describe will facilitate characterization of loss-of-function perturbations using H. diminuta. This toolkit will enable a greater understanding of fundamental tapeworm biology that may elucidate new therapeutic targets toward the eradication of these parasites.

  15. Energy transfer in PPV-based conjugated polymers: a defocused widefield fluorescence microscopy study.

    Science.gov (United States)

    Hooley, E N; Tilley, A J; White, J M; Ghiggino, K P; Bell, T D M

    2014-04-21

    Both pendant and main chain conjugated MEH-PPV based polymers have been studied at the level of single chains using confocal and widefield fluorescence microscopy techniques. In particular, defocused widefield fluorescence is applied to reveal the extent of energy transfer in these polymers by identifying whether they act as single emitters. For main chain conjugated MEH-PPV, molecular weight and the surrounding matrix play a primary role in determining energy transport processes and whether single emitter behaviour is observed. Surprisingly in polymers with a saturated backbone but containing the same pendant MEH-PPV oligomer on each repeating unit, intra-chain energy transfer to a single emitter is also apparent. The results imply there is chromophore heterogeneity that can facilitate energy funneling to the emitting site. Both main chain conjugated and pendant MEH-PPV polymers exhibit changes in orientation of the emission dipole during a fluorescence trajectory of many seconds, whereas a model MEH-PPV oligomer does not. The results suggest that, in the polymers, the nature of the emitting chromophores can change during the time trajectory.

  16. Pattern of glomerular diseases in oman: A study based on light microscopy and immunofluorescence

    Directory of Open Access Journals (Sweden)

    Nasar Yousuf Alwahaibi

    2013-01-01

    Full Text Available Light microscopy and immunofluorescence play an important part in the final diagnosis of renal biopsy. The aim of this study was to analyze the pattern of various glomerular diseases in Oman. A total of 424 renal biopsies were retrospectively analyzed at the Sultan Qaboos University Hospital between 1999 and 2010. Focal and segmental glomerulosclerosis (FSGS, minimal change disease (MCD, membranous glomerulopathy (MGN and IgA nephropathy were the most common primary glomerular diseases encountered, accounting for 21.2%, 17%, 12.3% and 8.3%, respectively, of all cases. Lupus nephritis was the most common secondary glomerular disease and was the most prevalent among all biopsies, accounting for 30.4% of all biopsies. Amyloidosis was seen in only two cases. The presence of fluorescein isothiocyanatefibrin in all renal cases was low when compared with IgG, IgA, IgM, C3 and C1q markers. In conclusion, based on the findings of this study, lupus nephritis was the most common of all glomerular diseases and FSGS was the most common primary glomerular disease. The importance of fluorescein isothiocyanate-fibrin in the diagnosis of renal biopsy needs to be further investigated.

  17. Development of an automated asbestos counting software based on fluorescence microscopy.

    Science.gov (United States)

    Alexandrov, Maxym; Ichida, Etsuko; Nishimura, Tomoki; Aoki, Kousuke; Ishida, Takenori; Hirota, Ryuichi; Ikeda, Takeshi; Kawasaki, Tetsuo; Kuroda, Akio

    2015-01-01

    An emerging alternative to the commonly used analytical methods for asbestos analysis is fluorescence microscopy (FM), which relies on highly specific asbestos-binding probes to distinguish asbestos from interfering non-asbestos fibers. However, all types of microscopic asbestos analysis require laborious examination of large number of fields of view and are prone to subjective errors and large variability between asbestos counts by different analysts and laboratories. A possible solution to these problems is automated counting of asbestos fibers by image analysis software, which would lower the cost and increase the reliability of asbestos testing. This study seeks to develop a fiber recognition and counting software for FM-based asbestos analysis. We discuss the main features of the developed software and the results of its testing. Software testing showed good correlation between automated and manual counts for the samples with medium and high fiber concentrations. At low fiber concentrations, the automated counts were less accurate, leading us to implement correction mode for automated counts. While the full automation of asbestos analysis would require further improvements in accuracy of fiber identification, the developed software could already assist professional asbestos analysts and record detailed fiber dimensions for the use in epidemiological research.

  18. Stripe artifact elimination based on nonsubsampled contourlet transform for light sheet fluorescence microscopy

    Science.gov (United States)

    Liang, Xiao; Zang, Yali; Dong, Di; Zhang, Liwen; Fang, Mengjie; Yang, Xin; Arranz, Alicia; Ripoll, Jorge; Hui, Hui; Tian, Jie

    2016-10-01

    Stripe artifacts, caused by high-absorption or high-scattering structures in the illumination light path, are a common drawback in both unidirectional and multidirectional light sheet fluorescence microscopy (LSFM), significantly deteriorating image quality. To circumvent this problem, we present an effective multidirectional stripe remover (MDSR) method based on nonsubsampled contourlet transform (NSCT), which can be used for both unidirectional and multidirectional LSFM. In MDSR, a fast Fourier transform (FFT) filter is designed in the NSCT domain to shrink the stripe components and eliminate the noise. Benefiting from the properties of being multiscale and multidirectional, MDSR succeeds in eliminating stripe artifacts in both unidirectional and multidirectional LSFM. To validate the method, MDSR has been tested on images from a custom-made unidirectional LSFM system and a commercial multidirectional LSFM system, clearly demonstrating that MDSR effectively removes most of the stripe artifacts. Moreover, we performed a comparative experiment with the variational stationary noise remover and the wavelet-FFT methods and quantitatively analyzed the results with a peak signal-to-noise ratio, showing an improved noise removal when using the MDSR method.

  19. Structural changes in a Schiff base molecular assembly initiated by scanning tunneling microscopy tip

    Science.gov (United States)

    Tomak, A.; Bacaksiz, C.; Mendirek, G.; Sahin, H.; Hur, D.; Görgün, K.; Senger, R. T.; Birer, Ö.; Peeters, F. M.; Zareie, H. M.

    2016-08-01

    We report the controlled self-organization and switching of newly designed Schiff base (E)-4-((4-(phenylethynyl) benzylidene) amino) benzenethiol (EPBB) molecules on a Au (111) surface at room temperature. Scanning tunneling microscopy and spectroscopy (STM/STS) were used to image and analyze the conformational changes of the EPBB molecules. The conformational change of the molecules was induced by using the STM tip while increasing the tunneling current. The switching of a domain or island of molecules was shown to be induced by the STM tip during scanning. Unambiguous fingerprints of the switching mechanism were observed via STM/STS measurements. Surface-enhanced Raman scattering was employed, to control and identify quantitatively the switching mechanism of molecules in a monolayer. Density functional theory calculations were also performed in order to understand the microscopic details of the switching mechanism. These calculations revealed that the molecular switching behavior stemmed from the strong interaction of the EPBB molecules with the STM tip. Our approach to controlling intermolecular mechanics provides a path towards the bottom-up assembly of more sophisticated molecular machines.

  20. The bacterial rhizobiome of hyperaccumulators: future perspectives based on omics analysis and advanced microscopy

    Directory of Open Access Journals (Sweden)

    Giovanna eVisioli

    2015-01-01

    Full Text Available Hyperaccumulators are plants that can extract heavy metal ions from the soil and translocate those ions to the shoots, where they are sequestered and detoxified. Hyperaccumulation depends not only on the availability of mobilized metal ions in the soil, but also on the enhanced activity of metal transporters and metal chelators which may be provided by the plant or its associated microbes. The rhizobiome is captured by plant root exudates from the complex microbial community in the soil, and may colonize the root surface or infiltrate the root cortex. This community can increase the root surface area by inducing hairy root proliferation. It may also increase the solubility of metals in the rhizosphere and promote the uptake of soluble metals by the plant. The bacterial rhizobiome, a subset of specialized microorganisms that colonize the plant rhizosphere and endosphere, makes an important contribution to the hyperaccumulator phenotype. In this review, we discuss classic and more recent tools that are used to study the interactions between hyperaccumulators and the bacterial rhizobiome, and consider future perspectives based on the use of omics analysis and microscopy to study plant metabolism in the context of metal accumulation. Recent data suggest that metal-resistant bacteria isolated from the hyperaccumulator rhizosphere and endosphere could be useful in applications such as phytoextraction and phytoremediation, although more research is required to determine whether such properties can be transferred successfully to non-accumulator species.

  1. Modeling the Effect of Wave-front Aberrations in Fiber-based Scanning Optical Microscopy

    NARCIS (Netherlands)

    Verstraete, H.R.G.W.; Verhaegen, M.H.G.; Kalkman, J.

    2013-01-01

    In scanning microscopy and optical coherence tomography, aberrations of the wave-front cause a loss in intensity and resolution. Intensity and resolution are quantified using Fresnel propagation, Fraunhofer diffraction, and the calculation of overlap integrals.

  2. From the patient to the clinical mycology laboratory: how can we optimise microscopy and culture methods for mould identification?

    Science.gov (United States)

    Vyzantiadis, Timoleon-Achilleas A; Johnson, Elizabeth M; Kibbler, Christopher C

    2012-06-01

    The identification of fungi relies mainly on morphological criteria. However, there is a need for robust and definitive phenotypic identification procedures in order to evaluate continuously evolving molecular methods. For the future, there is an emerging consensus that a combined (phenotypic and molecular) approach is more powerful for fungal identification, especially for moulds. Most of the procedures used for phenotypic identification are based on experience rather than comparative studies of effectiveness or performance and there is a need for standardisation among mycology laboratories. This review summarises and evaluates the evidence for the major existing phenotypic identification procedures for the predominant causes of opportunistic mould infection. We have concentrated mainly on Aspergillus, Fusarium and mucoraceous mould species, as these are the most important clinically and the ones for which there are the most molecular taxonomic data.

  3. Transmission electron microscopy of GaN based, doped semiconductor heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Pretorius, A.

    2006-07-01

    This thesis addresses the analysis of GaN based heterostructures with transmission electron microscopy (TEM). Basic properties of the material of interest are introduced in chapter 2. These include the structural and optical properties as well as an introduction to the growth methods used for the samples analysed in this work. In chapter 3 a brief theoretical treatment of TEM is given. As one main topic of this work is the determination of the In concentration in InGaN islands using strain state analysis, a detailed description of the method is given. Chapter 4 describes the results obtained for pyramidal defects present in metalorganic vapour phase epitaxy grown GaN:Mg with high dopant concentration. Based on the experimental results and the well established knowledge that GaN of inverted polarity is present inside the pyramidal defects, a variety of basal plane inversion domain boundary models was set up. From these models, HRTEM images were simulated using the multislice approach, followed by a quantitative comparison to experimentally obtained HRTEM images. Another focus of this work is the analysis of In{sub x}Ga{sub 1-x}N islands grown on GaN presented in chapter 5. Following a literature survey which describes different methods used to obtain In{sub x}Ga{sub 1-x}N islands, the first topic is the distinction of In{sub x}Ga{sub 1-x}N islands and metal droplets, which can form during growth. This is followed by the experimental results of molecular beam epitaxy and metalorganic vapour phase epitaxy grown In{sub x}Ga{sub 1-x}N island and quantum dot samples. (orig.)

  4. Clinical data interoperability based on archetype transformation.

    Science.gov (United States)

    Costa, Catalina Martínez; Menárguez-Tortosa, Marcos; Fernández-Breis, Jesualdo Tomás

    2011-10-01

    The semantic interoperability between health information systems is a major challenge to improve the quality of clinical practice and patient safety. In recent years many projects have faced this problem and provided solutions based on specific standards and technologies in order to satisfy the needs of a particular scenario. Most of such solutions cannot be easily adapted to new scenarios, thus more global solutions are needed. In this work, we have focused on the semantic interoperability of electronic healthcare records standards based on the dual model architecture and we have developed a solution that has been applied to ISO 13606 and openEHR. The technological infrastructure combines reference models, archetypes and ontologies, with the support of Model-driven Engineering techniques. For this purpose, the interoperability infrastructure developed in previous work by our group has been reused and extended to cover the requirements of data transformation.

  5. Exploring nanoscale electrical and electronic properties of organic and polymeric functional materials by atomic force microscopy based approaches.

    Science.gov (United States)

    Palermo, Vincenzo; Liscio, Andrea; Palma, Matteo; Surin, Mathieu; Lazzaroni, Roberto; Samorì, Paolo

    2007-08-28

    Beyond imaging, atomic force microscopy (AFM) based methodologies enable the quantitative investigation of a variety of physico-chemical properties of (multicomponent) materials with a spatial resolution of a few nanometers. This Feature Article is focused on two AFM modes, i.e. conducting and Kelvin probe force microscopies, which allow the study of electrical and electronic properties of organic thin films, respectively. These nanotools provide a wealth of information on (dynamic) characteristics of tailor-made functional architectures, opening pathways towards their technological application in electronics, catalysis and medicine.

  6. All-optical optoacoustic microscopy system based on probe beam deflection technique

    Science.gov (United States)

    Maswadi, Saher M.; Tsyboulskic, Dmitri; Roth, Caleb C.; Glickman, Randolph D.; Beier, Hope T.; Oraevsky, Alexander A.; Ibey, Bennett L.

    2016-03-01

    It is difficult to achieve sub-micron resolution in backward mode OA microscopy using conventional piezoelectric detectors, because of wavefront distortions caused by components placed in the optical path, between the sample and the objective lens, that are required to separate the acoustic wave from the optical beam. As an alternate approach, an optoacoustic microscope (OAM) was constructed using the probe beam deflection technique (PBDT) to detect laserinduced acoustic signals. The all-optical OAM detects laser-generated pressure waves using a probe beam passing through a coupling medium, such as water, filling the space between the microscope objective lens and sample. The acoustic waves generated in the sample propagate through the coupling medium, causing transient changes in the refractive index that deflect the probe beam. These deflections are measured with a high-speed, balanced photodiode position detector. The deflection amplitude is directly proportional to the magnitude of the acoustic pressure wave, and provides the data required for image reconstruction. The sensitivity of the PBDT detector expressed as noise equivalent pressure was 12 Pa, comparable to that of existing high-performance ultrasound detectors. Because of the unimpeded working distance, a high numerical aperture objective lens, i.e. NA = 1, was employed in the OAM to achieve near diffraction-limited lateral resolution of 0.5 μm at 532nm. The all-optical OAM provides several benefits over current piezoelectric detector-based systems, such as increased lateral and axial resolution, higher sensitivity, robustness, and potentially more compatibility with multimodal instruments.

  7. Model-based segmentation and quantification of subcellular structures in 2D and 3D fluorescent microscopy images

    Science.gov (United States)

    Wörz, Stefan; Heinzer, Stephan; Weiss, Matthias; Rohr, Karl

    2008-03-01

    We introduce a model-based approach for segmenting and quantifying GFP-tagged subcellular structures of the Golgi apparatus in 2D and 3D microscopy images. The approach is based on 2D and 3D intensity models, which are directly fitted to an image within 2D circular or 3D spherical regions-of-interest (ROIs). We also propose automatic approaches for the detection of candidates, for the initialization of the model parameters, and for adapting the size of the ROI used for model fitting. Based on the fitting results, we determine statistical information about the spatial distribution and the total amount of intensity (fluorescence) of the subcellular structures. We demonstrate the applicability of our new approach based on 2D and 3D microscopy images.

  8. Korean Clinic Based Outcome Measure Studies

    Directory of Open Access Journals (Sweden)

    Jongbae Park

    2003-02-01

    Full Text Available Background: Evidence based medicine has become main tools for medical practice. However, conducting a highly ranked in the evidence hierarchy pyramid is not easy or feasible at all times and places. There remains a room for descriptive clinical outcome measure studies with admitting the limit of the intepretation. Aims: Presents three Korean clinic based outcome measure studies with a view to encouraging Korean clinicians to conduct similar studies. Methods: Three studies are presented briefly here including 1 Quality of Life of liver cancer patients after 8 Constitutional acupuncture; 2 Developing a Korean version of Measuring yourself Medical Outcome profile (MYMOP; and 3 Survey on 5 Shu points: a pilot In the first study, we have included 4 primary or secondary liver cancer patients collecting their diagnostic X-ray film and clinical data f개m their hospital, and asked them to fill in the European Organization Research and Treatment of Cancer, Quality of Life Questionnaire before the commencement of the treatment. The acupuncture treatment is set up format but not disclosed yet. The translation and developing a Korean version of outcome measures that is Korean clinician friendly has been sought for MYMOP is one of the most appropriate one. The permission was granted, the translation into Korean was done, then back translated into English only based on the Korean translation by the researcher who is bilingual in both languages. The back translation was compared by the original developer of MYMOP and confirmed usable. In order to test the existence of acupoints and meridians through popular forms of Korean acupuncture regimes, we aim at collecting opinions from 101 Korean clinicians that have used those forms. The questions asked include most effective symptoms, 5 Shu points, points those are least likely to use due to either adverse events or the lack of effectiveness, theoretical reasons for the above proposals, proposing outcome measures

  9. Clinical applications of plasma based electrosurgical systems

    Science.gov (United States)

    Woloszko, Jean; Endler, Ashley; Ryan, Thomas P.; Stalder, Kenneth R.

    2013-02-01

    Over the past 18 years, several electrosurgical systems generating a low temperature plasma in an aqueous conductive solution have been commercialized for various clinical applications and have been used in over 10 million patients to date. The most popular utilizations are in arthroscopic surgery, otorhinolaryngology surgery, spine and neurosurgery, urology and wound care. These devices can be configured to bring saline to the tip and to have concomitant aspiration to remove by-products and excess fluid. By tuning the electrode geometry, waveform and fluid dynamic at the tip of the devices, tissue resection and thermal effects can be adjusted individually. This allows one to design products that can operate as precise tissue dissectors for treatment of articular cartilage or debridement of chronic wounds, as well as global tissue debulking devices providing sufficient concomitant hemostasis for applications like tonsillectomies. Effects of these plasma based electrosurgical devices on cellular biology, healing response and nociceptive receptors has also been studied in various models. This talk will include a review of the clinical applications, with product descriptions, results and introductory review of some of the research on the biological effects of these devices.

  10. Super-resolution optical microscopy based on scannable cantilever-combined microsphere.

    Science.gov (United States)

    Wang, Shuying; Zhang, Dongxian; Zhang, Haijun; Han, Xu; Xu, Rui

    2015-12-01

    We report an ingenious method of super-resolution optical microscopy utilizing scannable cantilever-combined microsphere. By scanning the microsphere over the sample surface in a cantilever-combined microsphere-sample contact state, super-resolution images can be acquired at arbitrary sample regions through near-field information collection by the microsphere. In addition, such a state can effectively reduce the possibility of breaking the cantilever and damaging the microsphere or sample surface. This work has developed a new method and technique of sub-diffraction-limit optical microscopy, and can be practically applied in various fields of micro/nanoscopy.

  11. Electron Microscopy.

    Science.gov (United States)

    Beer, Michael

    1980-01-01

    Reviews technical aspects of structure determination in biological electron microscopy (EM). Discusses low dose EM, low temperature microscopy, electron energy loss spectra, determination of mass or molecular weight, and EM of labeled systems. Cites 34 references. (CS)

  12. Combined microscopies study of the C-contamination induced by extreme-ultraviolet radiation: A surface-dependent secondary-electron-based model

    Science.gov (United States)

    Prezioso, S.; Donarelli, M.; Bisti, F.; Palladino, L.; Santucci, S.; Spadoni, S.; Avaro, L.; Liscio, A.; Palermo, V.; Ottaviano, L.

    2012-05-01

    SiO2 and Al2O3 surfaces exposed to periodically modulated extreme ultraviolet (EUV) light (λ = 46.9 nm) have been investigated at the μm scale by optical microscopy, scanning electron microscopy, scanning Auger microscopy, atomic force microscopy, and Kelvin probe force microscopy. The formation of a carbon contamination layer preserving the same periodical modulation of the EUV dose has been observed. The mechanisms of hydrocarbon molecules deposition have been studied with the help of correlation plots between the modulated Auger signal and the corresponding EUV dose. A surface-dependent secondary-electron-based model has been proposed.

  13. Combined microscopies study of the C-contamination induced by extreme-ultraviolet radiation: A surface-dependent secondary-electron-based model

    Energy Technology Data Exchange (ETDEWEB)

    Prezioso, S.; Donarelli, M.; Bisti, F.; Palladino, L.; Santucci, S.; Ottaviano, L. [Dip. di Fisica, Universita dell' Aquila, Via Vetoio, 67100 L' Aquila (Italy); Spadoni, S.; Avaro, L. [Micron, Process R and D, Via C. Olivetti 2, 20864 Agrate Brianza (Italy); Liscio, A.; Palermo, V. [CNR-ISOF, Via Gobetti 101, 40129 Bologna (Italy)

    2012-05-14

    SiO{sub 2} and Al{sub 2}O{sub 3} surfaces exposed to periodically modulated extreme ultraviolet (EUV) light ({lambda} = 46.9 nm) have been investigated at the {mu}m scale by optical microscopy, scanning electron microscopy, scanning Auger microscopy, atomic force microscopy, and Kelvin probe force microscopy. The formation of a carbon contamination layer preserving the same periodical modulation of the EUV dose has been observed. The mechanisms of hydrocarbon molecules deposition have been studied with the help of correlation plots between the modulated Auger signal and the corresponding EUV dose. A surface-dependent secondary-electron-based model has been proposed.

  14. Structured Illumination-Based Super-Resolution Optical Microscopy for Hemato- and Cyto-Pathology Applications

    Directory of Open Access Journals (Sweden)

    Tieqiao Zhang

    2013-01-01

    Full Text Available Structured illumination fluorescence microscopy utilizes interfering light and the moiré effect to enhance spatial resolution to about a half of that of conventional light microscopy, i.e. approximately 90 nm. In addition to the enhancement in the x and y directions, it also allows enhancement of resolution in the z- direction by the same factor of two (to approximately 220 nm, making it a powerful tool for 3-D morphology studies of fluorescently labeled cells or thin tissue sections. In this report, we applied this technique to several types of blood cells that are commonly seen in hematopathology. Compared with standard brightfield and ordinary fluorescence microscopy images, the 3-D morphology results clearly reveal the morphological features of different types of normal blood cells. We have also used this technique to evaluate morphologies of abnormal erythrocytes and compare them with those recorded on normal cells. The results give a very intuitive presentation of morphological structures of erythrocytes with great details. This research illustrates the potential of this technique to be used in hematology and cyto-pathology studies aimed at identifying nanometer-sized features that cannot be distinguished otherwise with conventional optical microscopy.

  15. Structured illumination-based super-resolution optical microscopy for hemato- and cyto-pathology applications.

    Science.gov (United States)

    Zhang, Tieqiao; Osborn, Samantha; Brandow, Chloe; Dwyre, Denis; Green, Ralph; Lane, Stephen; Wachsmann-Hogiu, Sebastian

    2013-01-01

    Structured illumination fluorescence microscopy utilizes interfering light and the moiré effect to enhance spatial resolution to about a half of that of conventional light microscopy, i.e. approximately 90 nm. In addition to the enhancement in the x and y directions, it also allows enhancement of resolution in the z- direction by the same factor of two (to approximately 220 nm), making it a powerful tool for 3-D morphology studies of fluorescently labeled cells or thin tissue sections. In this report, we applied this technique to several types of blood cells that are commonly seen in hematopathology. Compared with standard brightfield and ordinary fluorescence microscopy images, the 3-D morphology results clearly reveal the morphological features of different types of normal blood cells. We have also used this technique to evaluate morphologies of abnormal erythrocytes and compare them with those recorded on normal cells. The results give a very intuitive presentation of morphological structures of erythrocytes with great details. This research illustrates the potential of this technique to be used in hematology and cyto-pathology studies aimed at identifying nanometer-sized features that cannot be distinguished otherwise with conventional optical microscopy.

  16. Visualization of magnetic dipolar interaction based on scanning transmission X-ray microscopy

    Science.gov (United States)

    Ohtori, Hiroyuki; Iwano, Kaoru; Mitsumata, Chiharu; Takeichi, Yasuo; Yano, Masao; Kato, Akira; Miyamoto, Noritaka; Shoji, Tetsuya; Manabe, Akira; Ono, Kanta

    2014-04-01

    Using scanning transmission X-ray microscopy (STXM), in this report we visualized the magnetic dipolar interactions in nanocrystalline Nd-Fe-B magnets and imaged their magnetization distributions at various applied fields. We calculated the magnetic dipolar interaction by analyzing the interaction between the magnetization at each point and those at the other points on the STXM image.

  17. Evidence Based Studies in Clinical Transfusion Medicine

    NARCIS (Netherlands)

    A.J.G. Jansen (Gerard)

    2007-01-01

    textabstractAfter the introduction of blood component therapy in the 1960s, more and more attention is given to clinical transfusion medicine. Although blood transfusion is an important treatment in different clinical settings, there are still lack of much randomized clinical trials. Nowadays bloo

  18. Non parametric denoising methods based on wavelets: Application to electron microscopy images in low exposure time

    Energy Technology Data Exchange (ETDEWEB)

    Soumia, Sid Ahmed, E-mail: samasoumia@hotmail.fr [Science and Technology Faculty, El Bachir El Ibrahimi University, BordjBouArreridj (Algeria); Messali, Zoubeida, E-mail: messalizoubeida@yahoo.fr [Laboratory of Electrical Engineering(LGE), University of M' sila (Algeria); Ouahabi, Abdeldjalil, E-mail: abdeldjalil.ouahabi@univ-tours.fr [Polytechnic School, University of Tours (EPU - PolytechTours), EPU - Energy and Electronics Department (France); Trepout, Sylvain, E-mail: sylvain.trepout@curie.fr, E-mail: cedric.messaoudi@curie.fr, E-mail: sergio.marco@curie.fr; Messaoudi, Cedric, E-mail: sylvain.trepout@curie.fr, E-mail: cedric.messaoudi@curie.fr, E-mail: sergio.marco@curie.fr; Marco, Sergio, E-mail: sylvain.trepout@curie.fr, E-mail: cedric.messaoudi@curie.fr, E-mail: sergio.marco@curie.fr [INSERMU759, University Campus Orsay, 91405 Orsay Cedex (France)

    2015-01-13

    The 3D reconstruction of the Cryo-Transmission Electron Microscopy (Cryo-TEM) and Energy Filtering TEM images (EFTEM) hampered by the noisy nature of these images, so that their alignment becomes so difficult. This noise refers to the collision between the frozen hydrated biological samples and the electrons beam, where the specimen is exposed to the radiation with a high exposure time. This sensitivity to the electrons beam led specialists to obtain the specimen projection images at very low exposure time, which resulting the emergence of a new problem, an extremely low signal-to-noise ratio (SNR). This paper investigates the problem of TEM images denoising when they are acquired at very low exposure time. So, our main objective is to enhance the quality of TEM images to improve the alignment process which will in turn improve the three dimensional tomography reconstructions. We have done multiple tests on special TEM images acquired at different exposure time 0.5s, 0.2s, 0.1s and 1s (i.e. with different values of SNR)) and equipped by Golding beads for helping us in the assessment step. We herein, propose a structure to combine multiple noisy copies of the TEM images. The structure is based on four different denoising methods, to combine the multiple noisy TEM images copies. Namely, the four different methods are Soft, the Hard as Wavelet-Thresholding methods, Bilateral Filter as a non-linear technique able to maintain the edges neatly, and the Bayesian approach in the wavelet domain, in which context modeling is used to estimate the parameter for each coefficient. To ensure getting a high signal-to-noise ratio, we have guaranteed that we are using the appropriate wavelet family at the appropriate level. So we have chosen âĂIJsym8âĂİ wavelet at level 3 as the most appropriate parameter. Whereas, for the bilateral filtering many tests are done in order to determine the proper filter parameters represented by the size of the filter, the range parameter and the

  19. Web-based virtual microscopy at the RWTH Aachen University: didactic concept, methods and analysis of acceptance by the students.

    Science.gov (United States)

    Merk, Magdalene; Knuechel, Ruth; Perez-Bouza, Alberto

    2010-12-20

    Fundamental knowledge of microscopic anatomy and pathology has always been an essential part in medical education. The traditional didactic concept comprises theoretical and practical lessons using a light microscope and glass slides. High-speed Internet connections and technical improvement in whole-slide digital microscopy (commonly termed "virtual microscopy") provide a new and attractive approach for both teachers and students. High picture quality and unlimited temporal and spatial availability of histology samples from different fields are key advantages of web-based digital microscopy. In this report we discuss the technical requirements, system efficiency, optical resolution and didactic concept. Furthermore, we present a review of the experience gained in the course of one year based on an analysis of student acceptance. Three groups with a total of 192 students between the 3rd and 5th year of medical studies attending the practical courses of general and advanced histopathology had access to both glass-mounted and digitalized slides. Prior to exams, students were asked to answer an anonymous questionnaire. The results of the study reflect the high acceptance and intensive use of the web-based digital histology by students, thus encouraging the development of further Web-based learning strategies for the teaching of histology and pathology.

  20. Electron microscopy study of the deactivation of nickel based catalysts for bio oil hydrodeoxygenation

    DEFF Research Database (Denmark)

    Gardini, Diego; Mortensen, Peter Mølgaard; Carvalho, Hudson W. P.

    2014-01-01

    Hydrodeoxygenation (HDO) is proposed as an efficient way to remove oxygen in bio-oil, improving its quality as a more sustainable alternative to conventional fuels in terms of CO2 neutrality and relative short production cycle [1]. Ni and Ni-MoS2 nanoparticles supported on ZrO2 show potential...... as high-pressure (100 bar) catalysts for purification of bio-oil by HDO. However, the catalysts deactivate in presence of sulfur, chlorine and potassium species, which are all naturally occurring in real bio-oil. The deactivation mechanisms of the Ni/ZrO2 have been investigated through scanning...... transmission electron microscopy (STEM), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Catalytic testing has been performed using guaiacol in 1-octanol acting as a model compound for bio-oil. Addition of sulphur (0.3 vol% octanethiol) in the feed...

  1. Fabrication of metal oxide nanostructures based on Atomic Force Microscopy lithography

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Atomic Force Microscopy (AFM) mechanical lithography is a simple but significant method for nanofabrication. In this work, we used this method to construct nanos- tructures on Pt/Cu bilayer metal electrodes under ambient conditions in air. The influence of various scratch parameters, such as the applied force, scan velocity and circle times, on the lithography patterns was investigated. The Pt-Cu-CuxO-Cu-Pt nanostructure was constructed by choosing suitable scratch parameters and oxidation at room temperature. The properties of the scratched regions were also investigated by friction force microscopy and conductive AFM (C-AFM). The I-V curves show symmetric and linear properties, and Ohmic contacts were formed. These results indicate that AFM mechanical lithography is a powerful tool for fabricating novel metal-semiconductor nanoelectronic devices.

  2. Time-Encoded Raman: Fiber-based, hyperspectral, broadband stimulated Raman microscopy

    CERN Document Server

    Karpf, Sebastian; Wieser, Wolfgang; Klein, Thomas; Huber, Robert

    2014-01-01

    Raman sensing and Raman microscopy are amongst the most specific optical technologies to identify the chemical compounds of unknown samples, and to enable label-free biomedical imaging with molecular contrast. However, the high cost and complexity, low speed, and incomplete spectral information provided by current technology are major challenges preventing more widespread application of Raman systems. To overcome these limitations, we developed a new method for stimulated Raman spectroscopy and Raman imaging using continuous wave (CW), rapidly wavelength swept lasers. Our all-fiber, time-encoded Raman (TICO-Raman) setup uses a Fourier Domain Mode Locked (FDML) laser source to achieve a unique combination of high speed, broad spectral coverage (750 cm-1 - 3150 cm-1) and high resolution (0.5 cm-1). The Raman information is directly encoded and acquired in time. We demonstrate quantitative chemical analysis of a solvent mixture and hyperspectral Raman microscopy with molecular contrast of plant cells.

  3. Fabrication of metal oxide nanostructures based on Atomic Force Microscopy lithography

    Institute of Scientific and Technical Information of China (English)

    ZHU XiaoYang; CHENG Gang; WANG ShuJie; DAI ShuXi; WAN ShaoMing; ZHANG XingTang; DU ZuLiang

    2008-01-01

    Atomic Force Microscopy (AFM) mechanical lithography is a simple but significant method for nanofabrication. In this work, we used this method to construct nanos-tructures on Pt/Cu bilayer metal electrodes under ambient conditions in air. The influence of various scratch parameters, such as the applied force, scan velocity and circle times, on the lithography patterns was investigated. The Pt-Cu-CuxO-Cu-Pt nanostructure was constructed by choosing suitable scratch parameters and oxidation at room temperature. The properties of the scratched regions were also investigated by friction force microscopy and conductive AFM (C-AFM). The/-Vcurves show symmetric and linear properties, and Ohmic contacts were formed. These results indicate that AFM mechanical lithography is a powerful tool for fabricating novel metal-semiconductor nanoelectronic devices.

  4. Model-based traction force microscopy reveals differential tension in cellular actin bundles.

    Science.gov (United States)

    Soiné, Jérôme R D; Brand, Christoph A; Stricker, Jonathan; Oakes, Patrick W; Gardel, Margaret L; Schwarz, Ulrich S

    2015-03-01

    Adherent cells use forces at the cell-substrate interface to sense and respond to the physical properties of their environment. These cell forces can be measured with traction force microscopy which inverts the equations of elasticity theory to calculate them from the deformations of soft polymer substrates. We introduce a new type of traction force microscopy that in contrast to traditional methods uses additional image data for cytoskeleton and adhesion structures and a biophysical model to improve the robustness of the inverse procedure and abolishes the need for regularization. We use this method to demonstrate that ventral stress fibers of U2OS-cells are typically under higher mechanical tension than dorsal stress fibers or transverse arcs.

  5. Characterization nanoparticles-based vaccines and vaccine candidates: a Transmission Electron Microscopy study

    Directory of Open Access Journals (Sweden)

    I. Menéndez I

    2016-05-01

    Full Text Available Transmission Electron Microscopy (TEM is a valuable tool for the biotech industry. This paper summarizes some of the contributions of MET in the characterization of the recombinant antigens are part of vaccines or vaccine candidates obtained in the CIGB. It mentions the use of complementary techniques MET (Negative staining, and immunoelectron that enhance visualization and ultrastructural characterization of the recombinant proteins obtained by Genetic Engineering.

  6. Pulse splitter-based nonlinear microscopy for live-cardiomyocyte imaging

    OpenAIRE

    Wang, Zhonghai; Qin, Wan; Shao, Yonghong; Ma, Siyu; Borg, Thomas K.; GAO, BRUCE Z.

    2014-01-01

    Second harmonic generation (SHG) microscopy is a new imaging technique used in sarcomeric-addition studies. However, during the early stage of cell culture in which sarcomeric additions occur, the neonatal cardiomyocytes that we have been working with are very sensitive to photodamage, the resulting high rate of cell death prevents systematic study of sarcomeric addition using a conventional SHG system. To address this challenge, we introduced use of the pulse-splitter system developed by Na ...

  7. Challenges of microtome-based serial block-face scanning electron microscopy in neuroscience.

    Science.gov (United States)

    Wanner, A A; Kirschmann, M A; Genoud, C

    2015-08-01

    Serial block-face scanning electron microscopy (SBEM) is becoming increasingly popular for a wide range of applications in many disciplines from biology to material sciences. This review focuses on applications for circuit reconstruction in neuroscience, which is one of the major driving forces advancing SBEM. Neuronal circuit reconstruction poses exceptional challenges to volume EM in terms of resolution, field of view, acquisition time and sample preparation. Mapping the connections between neurons in the brain is crucial for understanding information flow and information processing in the brain. However, information on the connectivity between hundreds or even thousands of neurons densely packed in neuronal microcircuits is still largely missing. Volume EM techniques such as serial section TEM, automated tape-collecting ultramicrotome, focused ion-beam scanning electron microscopy and SBEM (microtome serial block-face scanning electron microscopy) are the techniques that provide sufficient resolution to resolve ultrastructural details such as synapses and provides sufficient field of view for dense reconstruction of neuronal circuits. While volume EM techniques are advancing, they are generating large data sets on the terabyte scale that require new image processing workflows and analysis tools. In this review, we present the recent advances in SBEM for circuit reconstruction in neuroscience and an overview of existing image processing and analysis pipelines.

  8. Analytical Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    2006-06-01

    In the Analytical Microscopy group, within the National Center for Photovoltaic's Measurements and Characterization Division, we combine two complementary areas of analytical microscopy--electron microscopy and proximal-probe techniques--and use a variety of state-of-the-art imaging and analytical tools. We also design and build custom instrumentation and develop novel techniques that provide unique capabilities for studying materials and devices. In our work, we collaborate with you to solve materials- and device-related R&D problems. This sheet summarizes the uses and features of four major tools: transmission electron microscopy, scanning electron microscopy, the dual-beam focused-ion-beam workstation, and scanning probe microscopy.

  9. Recent advancements in the "water-window" microscopy with laser-plasma SXR source based on a double stream gas-puff target

    Science.gov (United States)

    Wachulak, P. W.

    2016-09-01

    An overview of our recent developments, regarding "water-window" soft X-ray (SXR) microscopy based on a laser-plasma double stream gas puff target sources is presented. The work, presented herein, describes two approaches to SXR microscopy. The first one is a low spatial resolution, achromatic SXR microscopy, employing Wolter type-I objective. The second one is a nanometer spatial resolution SXR microscopy, with the use of a Fresnel zone plate objective, for imaging various objects with quasimonochromatic light, emitted from a double stream gas puff target based short wavelength source. The developments regarding both systems are presented, as well as the possible applications, for which the SXR microscope was already employed. Such compact, table-top size, laboratory type microscopy setups may be employed in the near future for complementary-like studies to other, often used, microscopy techniques.

  10. Optical parametric oscillator-based light source for coherent Raman scattering microscopy: practical overview

    Science.gov (United States)

    Brustlein, Sophie; Ferrand, Patrick; Walther, Nico; Brasselet, Sophie; Billaudeau, Cyrille; Marguet, Didier; Rigneault, Hervé

    2011-02-01

    We present the assets and constraints of using optical parametric oscillators (OPOs) to perform point scanning nonlinear microscopy and spectroscopy with special emphasis on coherent Raman spectroscopy. The difterent possible configurations starting with one OPO and two OPOs are described in detail and with comments that are intended to be practically useful for the user. Explicit examples on test samples such as nonlinear organic crystal, polystyrene beads, and fresh mouse tissues are given. Special emphasis is given to background-free coherent Raman anti-Stokes scattering (CARS) imaging, including CARS hyperspectral imaging in a fully automated mode with commercial OPOs.

  11. Monolithically Integrated, Mechanically Resilient Carbon-Based Probes for Scanning Probe Microscopy

    Science.gov (United States)

    Kaul, Anupama B.; Megerian, Krikor G.; Jennings, Andrew T.; Greer, Julia R.

    2010-01-01

    Scanning probe microscopy (SPM) is an important tool for performing measurements at the nanoscale in imaging bacteria or proteins in biology, as well as in the electronics industry. An essential element of SPM is a sharp, stable tip that possesses a small radius of curvature to enhance spatial resolution. Existing techniques for forming such tips are not ideal. High-aspect-ratio, monolithically integrated, as-grown carbon nanofibers (CNFs) have been formed that show promise for SPM applications by overcoming the limitations present in wet chemical and separate substrate etching processes.

  12. Developing methods based on light sheet fluorescence microscopy for biophysical investigations of larval zebrafish

    Science.gov (United States)

    Taormina, Michael J.

    Adapting the tools of optical microscopy to the large-scale dynamic systems encountered in the development of multicellular organisms provides a path toward understanding the physical processes necessary for complex life to form and function. Obtaining quantitatively meaningful results from such systems has been challenging due to difficulty spanning the spatial and temporal scales representative of the whole, while also observing the many individual members from which complex and collective behavior emerges. A three-dimensional imaging technique known as light sheet fluorescence microscopy provides a number of significant benefits for surmounting these challenges and studying developmental systems. A thin plane of fluorescence excitation light is produced such that it coincides with the focal plane of an imaging system, providing rapid acquisition of optically sectioned images that can be used to construct a three-dimensional rendition of a sample. I discuss the implementation of this technique for use in larva of the model vertebrate Danio rerio (zebrafish). The nature of light sheet imaging makes it especially well suited to the study of large systems while maintaining good spatial resolution and minimizing damage to the specimen from excessive exposure to excitation light. I show the results from a comparative study that demonstrates the ability to image certain developmental processes non-destructively, while in contrast confocal microscopy results in abnormal growth due to phototoxicity. I develop the application of light sheet microscopy to the study of a previously inaccessible system: the bacterial colonization of a host organism. Using the technique, we are able to obtain a survey of the intestinal tract of a larval zebrafish and observe the location of microbes as they grow and establish a stable population in an initially germ free fish. Finally, I describe a new technique to measure the fluid viscosity of this intestinal environment in vivo using

  13. A dynamic scanning method based on signal-statistics for scanning electron microscopy.

    Science.gov (United States)

    Timischl, F

    2014-01-01

    A novel dynamic scanning method for noise reduction in scanning electron microscopy and related applications is presented. The scanning method dynamically adjusts the scanning speed of the electron beam depending on the statistical behavior of the detector signal and gives SEM images with uniform and predefined standard deviation, independent of the signal value itself. In the case of partially saturated images, the proposed method decreases image acquisition time without sacrificing image quality. The effectiveness of the proposed method is shown and compared to the conventional scanning method and median filtering using numerical simulations.

  14. Quantitative analysis on collagen morphology in aging skin based on multiphoton microscopy

    Science.gov (United States)

    Wu, Shulian; Li, Hui; Yang, Hongqin; Zhang, Xiaoman; Li, Zhifang; Xu, Shufei

    2011-04-01

    Multiphoton microscopy was employed for monitoring the structure changes of mouse dermis collagen in the intrinsic- or the extrinsic-age-related processes in vivo. The characteristics of textures in different aging skins were uncovered by fast Fourier transform in which the orientation index and bundle packing of collagen were quantitatively analyzed. Some significant differences in collagen-related changes are found in different aging skins, which can be good indicators for the statuses of aging skins. The results are valuable to the study of aging skin and also of interest to biomedical photonics.

  15. Autofocusing of digital holographic microscopy based on off-axis illuminations.

    Science.gov (United States)

    Gao, Peng; Yao, Baoli; Min, Junwei; Guo, Rongli; Ma, Baiheng; Zheng, Juanjuan; Lei, Ming; Yan, Shaohui; Dan, Dan; Ye, Tong

    2012-09-01

    An auto-focusing method for digital holographic microscopy has been proposed by employing two off-axis illumination beams. When specimens are illuminated by two plane waves in different directions, it is found that the farther the reconstruction plane is from the image plane, the wider the two reconstructed images are separated from each other. Thus, the image plane can be determinated by finding the minimum of the variation between the two reconstructed object waves on both the amplitude and phase distributions. The feasibility of the proposed method is demonstrated by the corresponding simulation and experiment.

  16. Cost-effectiveness of malaria diagnosis using rapid diagnostic tests compared to microscopy or clinical symptoms alone in Afghanistan

    DEFF Research Database (Denmark)

    Hansen, Kristian S; Grieve, Eleanor; Mikhail, Amy;

    2015-01-01

    BACKGROUND: Improving access to parasitological diagnosis of malaria is a central strategy for control and elimination of the disease. Malaria rapid diagnostic tests (RDTs) are relatively easy to perform and could be used in primary level clinics to increase coverage of diagnostics and improve tr...

  17. Mapping of Proteomic Composition on the Surfaces of Bacillus spores by Atomic Force Microscopy-based Immunolabeling

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; Malkin, A J

    2008-06-02

    Atomic force microscopy provides a unique capability to image high-resolution architecture and structural dynamics of pathogens (e.g. viruses, bacteria and bacterial spores) at near molecular resolution in native conditions. Further development of atomic force microscopy in order to enable the correlation of pathogen protein surface structures with specific gene products is essential to understand the mechanisms of the pathogen life cycle. We have applied an AFM-based immunolabeling technique for the proteomic mapping of macromolecular structures through the visualization of the binding of antibodies, conjugated with nanogold particles, to specific epitopes on Bacillus spore surfaces. This information is generated while simultaneously acquiring the surface morphology of the pathogen. The immunospecificity of this labeling method was established through the utilization of specific polyclonal and monoclonal antibodies that target spore coat and exosporium epitopes of Bacillus atrophaeus and Bacillus anthracis spores.

  18. Campus Clinical: simulation-based curriculum designed to meet clinical course learning outcomes.

    Science.gov (United States)

    Jarvis, Michelle; Rivers, Julie

    2014-01-01

    Campus Clinical is a simulation-based curriculum designed to meet the challenge of decreasing clinical spaces in maternal-child units. The curriculum framework is situated in a constructivist, experiential learning context, integrating Chickering and Gamson's principles for good practice in education. This innovative approach to meeting clinical course learning outcomes is transferable to a variety of settings.

  19. Experimental validation of atomic force microscopy-based cell elasticity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Andrew R; Charras, G T, E-mail: g.charras@ucl.ac.uk [London Centre for Nanotechnology, University College London, London WC1H 0AH (United Kingdom)

    2011-08-26

    Atomic force microscopy (AFM) is widely used for measuring the elasticity of living cells yielding values ranging from 100 Pa to 100 kPa, much larger than those obtained using bead-tracking microrheology or micropipette aspiration (100-500 Pa). AFM elasticity measurements appear dependent on tip geometry with pyramidal tips yielding elasticities 2-3 fold larger than spherical tips, an effect generally attributed to the larger contact area of spherical tips. In AFM elasticity measurements, experimental force-indentation curves are analyzed using contact mechanics models that infer the tip-cell contact area from the tip geometry and indentation depth. The validity of these assumptions has never been verified. Here we utilize combined AFM-confocal microscopy of epithelial cells expressing a GFP-tagged membrane marker to directly characterize the indentation geometry and measure the indentation depth. Comparison with data derived from AFM force-indentation curves showed that the experimentally measured contact area for spherical tips agrees well with predicted values, whereas for pyramidal tips, the contact area can be grossly underestimated at forces larger than {approx} 0.2 nN leading to a greater than two-fold overestimation of elasticity. These data suggest that a re-examination of absolute cellular elasticities reported in the literature may be necessary and we suggest guidelines for avoiding elasticity measurement artefacts introduced by extraneous cantilever-cell contact.

  20. Role of clinical images based teaching as a supplement to conventional clinical teaching in dermatology

    Directory of Open Access Journals (Sweden)

    Gurumoorthy Rajesh Kumar

    2015-01-01

    Full Text Available Introduction : Clinical Dermatology is a visually oriented specialty, where visually oriented teaching is more important than it is in any other specialty. It is essential that students must have repeated exposure to common dermatological disorders in the limited hours of Dermatology clinical teaching. Aim: This study was conducted to assess the effect of clinical images based teaching as a supplement to the patient based clinical teaching in Dermatology, among final year MBBS students. Methods: A clinical batch comprising of 19 students was chosen for the study. Apart from the routine clinical teaching sessions, clinical images based teaching was conducted. This teaching method was evaluated using a retrospective pre-post questionnaire. Students′ performance was assessed using Photo Quiz and an Objective Structured Clinical Examination (OSCE. Feedback about the addition of images based class was collected from students. Results: A significant improvement was observed in the self-assessment scores following images based teaching. Mean OSCE score was 6.26/10, and that of Photo Quiz was 13.6/20. Conclusion : This Images based Dermatology teaching has proven to be an excellent supplement to routine clinical cases based teaching.

  1. Scanning thermal microscopy based on a modified atomic force microscope combined with pyroelectric detection

    Science.gov (United States)

    Antoniow, J.-S.; Chirtoc, M.; Trannoy, N.; Raphael, O.; Pelzl, J.

    2005-06-01

    We propose a novel approach in scanning thermal microscopy of layered samples. The thermal probe (ThP) (Wollaston wire) acts as a local a.c. heat source at the front of a sample layer deposited on a pyroelectric (PE) sensor. The PE signal is proportional to the heat wave transmitted through the sample. The ThP and PE signals can be used to generate complementary thermal conductivity maps and with some restrictions, thermal diffusivity maps of the sample. Additionally, the topography map is obtained in the usual way from the atomic force microscope. We give the theoretical background for the interpretation of PE signal obtained at low and at high frequency, and we demonstrate that it carries information on the thermal diffusivity of a test sample (12 μm thick PET polymer sheet). Finally, we discuss the contributions of heat transfer channels between ThP and sample, and the role of contact thermal resistance.

  2. Friedel oscillations in graphene-based systems probed by Scanning Tunneling Microscopy

    Science.gov (United States)

    Mallet, Pierre; Brihuega, Iván; Cherkez, Vladimir; Gómez-Rodríguez, Jose Marìa; Veuillen, Jean-Yves

    2016-03-01

    For the last 25 years, scientists have demonstrated the capabilities of Scanning Tunneling Microscopy (STM) to visualize in real space the response of a two-dimensional electron gas to atomic-scale impurities. The analysis of the Friedel oscillations surrounding the impurities yields valuable information regarding the elastic scattering properties, the band structure, the doping level and the symmetry of the electronic states in the two-dimensional host system. We will address in this article the use of this technique for probing the electronic properties of graphene, the star two-dimensional compound of the last decade. In particular, we will emphasize how this technique can be pushed up to unravel the electronic pseudospin, a distinctive degree of freedom of graphene's Dirac fermions.

  3. A model for the ultrastructure of bone based on electron microscopy of ion-milled sections.

    Directory of Open Access Journals (Sweden)

    Elizabeth A McNally

    Full Text Available The relationship between the mineral component of bone and associated collagen has been a matter of continued dispute. We use transmission electron microscopy (TEM of cryogenically ion milled sections of fully-mineralized cortical bone to study the spatial and topological relationship between mineral and collagen. We observe that hydroxyapatite (HA occurs largely as elongated plate-like structures which are external to and oriented parallel to the collagen fibrils. Dark field images suggest that the structures ("mineral structures" are polycrystalline. They are approximately 5 nm thick, 70 nm wide and several hundred nm long. Using energy-dispersive X-ray analysis we show that approximately 70% of the HA occurs as mineral structures external to the fibrils. The remainder is found constrained to the gap zones. Comparative studies of other species suggest that this structural motif is ubiquitous in all vertebrates.

  4. A novel Kalman filter based video image processing scheme for two-photon fluorescence microscopy

    Science.gov (United States)

    Sun, Wenqing; Huang, Xia; Li, Chunqiang; Xiao, Chuan; Qian, Wei

    2016-03-01

    Two-photon fluorescence microscopy (TPFM) is a perfect optical imaging equipment to monitor the interaction between fast moving viruses and hosts. However, due to strong unavoidable background noises from the culture, videos obtained by this technique are too noisy to elaborate this fast infection process without video image processing. In this study, we developed a novel scheme to eliminate background noises, recover background bacteria images and improve video qualities. In our scheme, we modified and implemented the following methods for both host and virus videos: correlation method, round identification method, tree-structured nonlinear filters, Kalman filters, and cell tracking method. After these procedures, most of noises were eliminated and host images were recovered with their moving directions and speed highlighted in the videos. From the analysis of the processed videos, 93% bacteria and 98% viruses were correctly detected in each frame on average.

  5. Memory-effect based deconvolution microscopy for super-resolution imaging through scattering media

    Science.gov (United States)

    Edrei, Eitan; Scarcelli, Giuliano

    2016-09-01

    High-resolution imaging through turbid media is a fundamental challenge of optical sciences that has attracted a lot of attention in recent years for its wide range of potential applications. Here, we demonstrate that the resolution of imaging systems looking behind a highly scattering medium can be improved below the diffraction-limit. To achieve this, we demonstrate a novel microscopy technique enabled by the optical memory effect that uses a deconvolution image processing and thus it does not require iterative focusing, scanning or phase retrieval procedures. We show that this newly established ability of direct imaging through turbid media provides fundamental and practical advantages such as three-dimensional refocusing and unambiguous object reconstruction.

  6. Monitoring the progression from intraductal carcinoma to invasive ductal carcinoma based on multiphoton microscopy

    Science.gov (United States)

    Wu, Yan; Fu, Fangmeng; Lian, Yuane; Nie, Yuting; Zhuo, Shuangmu; Wang, Chuan; Chen, Jianxin

    2015-09-01

    Intraductal carcinoma is a precancerous lesion of the breast and the immediate precursor of invasive ductal carcinoma. Multiphoton microscopy (MPM) was used to monitor the progression from intraductal carcinoma to invasive ductal carcinoma, which can improve early detection of precursor lesions and halt progression to invasive neoplastic disease. It was found that MPM has the capability to reveal the qualitative changes in features of cells, structure of basement membranes, and architecture of collagens during the development from intraductal carcinoma to invasive ductal carcinoma, as well as the quantitative alterations in nuclear area, circle length of basement membrane, and collagen density. Combined with intra-fiberoptic ductoscopy or transdermal biopsy needle, MPM has the potential to provide immediate histological diagnosis of tumor progression in the field of breast carcinoma.

  7. Laboratory source based full-field x-ray microscopy at 9 keV

    Energy Technology Data Exchange (ETDEWEB)

    Fella, C.; Balles, A.; Wiest, W. [Lehrstuhl für Röntgenmikroskopie, Julius-Maximilians-Universität, 97074 Würzburg (Germany); Zabler, S.; Hanke, R. [Lehrstuhl für Röntgenmikroskopie, Julius-Maximilians-Universität, 97074 Würzburg (Germany); Fraunhofer Development Center X-Ray Technology (EZRT), Flugplatzstrasse 75, 90768 Fürth (Germany)

    2016-01-28

    In the past decade, hard x-ray transmission microscopy experienced tremendous developments. With the avail-ability of efficient Fresnel zone plates, even set-ups utilizing laboratory sources were developed [1]. In order to improve the performance of these x-ray microscopes, novel approaches to fabricate optical elements [2] and brighter x-ray tubes [3] are promising candidates. We are currently building a laboratory transmission x-ray microscope for 9.25 keV, using an electron impact liquid-metal-jet anode source. Up to now, the further elements of our setup are: a polycapillary condenser, a tungsten zone plate, and a scintillator which is optically coupled to a CMOS camera. However, further variations in terms of optical elements are intended. Here we present the current status of our work, as well as first experimental results.

  8. Fluorescence antibunching microscopy

    CERN Document Server

    Schwartz, Osip

    2011-01-01

    Breaking the diffraction limit in microscopy by utilizing quantum properties of light has been the goal of intense research in the recent years. We propose a quantum superresolution technique based on non-classical emission statistics of fluorescent markers, routinely used as contrast labels for bio-imaging. The technique can be readily implemented using standard fluorescence microscopy equipment.

  9. Adaptive optics in nonlinear microscopy implemented with open-loop control and EMCCD-based Shack-Hartmann wavefront sensor

    Science.gov (United States)

    Sun, Wei

    Nonlinear microscopy, with its unique advantages over conventional confocal fluorescence microscopy, has been widely adopted to study biological processes at the cellular level. However, like all other high-resolution optical imaging techniques, nonlinear microscopy suffers from focal degradation due to optical aberrations in the sample as a result of refractive index mismatch. Optical aberrations distort the wavefront of the excitation beam, causing the focal spot to be larger than the diffraction limit. Since the fluorescence efficiency scales nonlinearly with the profile of the focusing excitation beam, aberrations further degrade the image brightness in addition to resolution. In this dissertation I describe the design, characterization and experimentation of an adaptive optics (AO) nonlinear laser scanning microscope implemented with open-loop control and an EMCCD-based Shack-Hartmann wavefront sensor (EMCCD SHWFS) for aberration compensation. Adaptive optics (AO), originally designed for ground-based astronomical observatories to correct for the aberrations from atmospheric turbulence while imaging distant stars and planets, has benefited many biomedical imaging platforms. We integrated a microelectromechanical system (MEMS) deformable mirror (DM) into our nonlinear laser scanning microscope. With an accurate open-loop control mechanism, which predicts the control voltages and generates a prescribed surface shape on the MEMS DM, known aberrations in the system can be compensated for with this computationally simple and inherently fast method. The use of a nonlinear guide star imbedded within the sample can reflect the sample aberration. However, the low level of nonlinear fluorescence signal is usually detected by photomultiplier tubes (PMT) and is below the sensitivity of a conventional charge-coupled device (CCD) based Shack-Hartmann wavefront sensor. This dissertation also describes the design of an EMCCD SHWFS to measure the wavefront distortion from the

  10. Molecular and Clinical Based Cardiovascular Care Program

    Science.gov (United States)

    2010-11-01

    Unrelated Hospitalization - r/o cerebral aneurysm Unrelated Malignant ovarian CA - TAH/BSO Unrelated Worsening right great toe pain (required follow-up...distributed to all nurses working on inpatient wards and in outpatient clinics for adult medicine and surgery, gynecology, pediatrics , psychiatry

  11. Annotating Evidence Based Clinical Guidelines: A Lightweight Ontology

    NARCIS (Netherlands)

    R. Hoekstra; A. de Waard; R. Vdovjak

    2012-01-01

    This paper describes a lightweight ontology for representing annotations of declarative evidence based clinical guidelines. We present the motivation and requirements for this representation, based on an analysis of several guidelines. The ontology provides the means to connect clinical questions an

  12. An innovative clinical practicum to teach evidence-based practice.

    Science.gov (United States)

    Brancato, Vera C

    2006-01-01

    A clinical practicum was successfully implemented for RN to BSN students to apply evidence-based practice to actual clinical problems affecting nursing practice. The author describes how this practicum was implemented and the requisite resources and support systems. This senior-level capstone course enabled students to understand and value a lifelong learning approach to evidence-based practice.

  13. Nanoscale characterization of local structures and defects in photonic crystals using synchrotron-based transmission soft X-ray microscopy

    Science.gov (United States)

    Nho, Hyun Woo; Kalegowda, Yogesh; Shin, Hyun-Joon; Yoon, Tae Hyun

    2016-04-01

    For the structural characterization of the polystyrene (PS)-based photonic crystals (PCs), fast and direct imaging capabilities of full field transmission X-ray microscopy (TXM) were demonstrated at soft X-ray energy. PS-based PCs were prepared on an O2-plasma treated Si3N4 window and their local structures and defects were investigated using this label-free TXM technique with an image acquisition speed of ~10 sec/frame and marginal radiation damage. Micro-domains of face-centered cubic (FCC (111)) and hexagonal close-packed (HCP (0001)) structures were dominantly found in PS-based PCs, while point and line defects, FCC (100), and 12-fold symmetry structures were also identified as minor components. Additionally, in situ observation capability for hydrated samples and 3D tomographic reconstruction of TXM images were also demonstrated. This soft X-ray full field TXM technique with faster image acquisition speed, in situ observation, and 3D tomography capability can be complementally used with the other X-ray microscopic techniques (i.e., scanning transmission X-ray microscopy, STXM) as well as conventional characterization methods (e.g., electron microscopic and optical/fluorescence microscopic techniques) for clearer structure identification of self-assembled PCs and better understanding of the relationship between their structures and resultant optical properties.

  14. Nanoscale characterization of local structures and defects in photonic crystals using synchrotron-based transmission soft X-ray microscopy

    Science.gov (United States)

    Nho, Hyun Woo; Kalegowda, Yogesh; Shin, Hyun-Joon; Yoon, Tae Hyun

    2016-01-01

    For the structural characterization of the polystyrene (PS)-based photonic crystals (PCs), fast and direct imaging capabilities of full field transmission X-ray microscopy (TXM) were demonstrated at soft X-ray energy. PS-based PCs were prepared on an O2-plasma treated Si3N4 window and their local structures and defects were investigated using this label-free TXM technique with an image acquisition speed of ~10 sec/frame and marginal radiation damage. Micro-domains of face-centered cubic (FCC (111)) and hexagonal close-packed (HCP (0001)) structures were dominantly found in PS-based PCs, while point and line defects, FCC (100), and 12-fold symmetry structures were also identified as minor components. Additionally, in situ observation capability for hydrated samples and 3D tomographic reconstruction of TXM images were also demonstrated. This soft X-ray full field TXM technique with faster image acquisition speed, in situ observation, and 3D tomography capability can be complementally used with the other X-ray microscopic techniques (i.e., scanning transmission X-ray microscopy, STXM) as well as conventional characterization methods (e.g., electron microscopic and optical/fluorescence microscopic techniques) for clearer structure identification of self-assembled PCs and better understanding of the relationship between their structures and resultant optical properties. PMID:27087141

  15. Micromorphology of cactus-pear (Opuntia ficus-indica (L.) Mill) cladodes based on scanning microscopies.

    Science.gov (United States)

    Ben Salem-Fnayou, Asma; Zemni, Hassène; Nefzaoui, Ali; Ghorbel, Abdelwahed

    2014-01-01

    Cladode ultrastructural features of two prickly and two spineless Opuntia ficus-indica cultivars were examined using environmental scanning electron and atomic force microscopies. Observations focused on cladode as well as spine and glochid surface micromorphologies. Prickly cultivars were characterized by abundant cracked epicuticular wax deposits covering the cladode surface, with an amorphous structure as observed by AFM, while less abundant waxy plates were observed by ESEM on spineless cultivar cladodes. Further AFM observations allowed a rough granular and crystalloid epicuticular wax structure to be distinguished in spineless cultivars. Regarding spine micromorphology, prickly cultivars had strong persistent spines, observed by ESEM as a compact arrangement of oblong epidermal cells with a rough granular structure. However, deciduous spines in spineless cultivars had a broken transversely fissured epidermis covering a parallel arrangement of fibres. Through AFM, the deciduous spine surface presented an irregular hilly and smooth microrelief while persistent spines exhibited rough helical filamentous prints. ESEM and AFM studies of cladode surfaces from prickly and spineless cactus pear cultivars revealed valuable micro-morphological details that ought to be extended to a large number of O. ficus-indica cultivars.

  16. Quantitative Conductive Atomic Force Microscopy on Single-Walled Carbon Nanotube-Based Polymer Composites.

    Science.gov (United States)

    Bârsan, Oana A; Hoffmann, Günter G; van der Ven, Leendert G J; de With, Gijsbertus

    2016-08-03

    Conductive atomic force microscopy (C-AFM) is a valuable technique for correlating the electrical properties of a material with its topographic features and for identifying and characterizing conductive pathways in polymer composites. However, aspects such as compatibility between tip material and sample, contact force and area between the tip and the sample, tip degradation and environmental conditions render quantifying the results quite challenging. This study aims at finding the suitable conditions for C-AFM to generate reliable, reproducible, and quantitative current maps that can be used to calculate the resistance in each point of a single-walled carbon nanotube (SWCNT) network, nonimpregnated as well as impregnated with a polymer. The results obtained emphasize the technique's limitation at the macroscale as the resistance of these highly conductive samples cannot be distinguished from the tip-sample contact resistance. Quantitative C-AFM measurements on thin composite sections of 150-350 nm enable the separation of sample and tip-sample contact resistance, but also indicate that these sections are not representative for the overall SWCNT network. Nevertheless, the technique was successfully used to characterize the local electrical properties of the composite material, such as sample homogeneity and resistance range of individual SWCNT clusters, at the nano- and microscale.

  17. Transmission electron microscopy investigations of the CdSe based quantum structures

    Energy Technology Data Exchange (ETDEWEB)

    Roventa, E.

    2006-09-22

    In this work, the structural morphology of the active region of the ZnSe laser diode: quaternary CdZnSSe quantum well or CdSe quantum dots embedded in CdSe/ZnSSe superlattices is investigated using Transmission Electron Microscopy. The conventional as well as high resolution imaging studies indicated that the degradation of the ZnSe laser diodes is connected with the formation of extended defects in the optical active region leading to a local strain relaxation of the quantum well. Furthermore the outdiffusion of Cd from the quantum well occurs predominantly where the defects are located. The chemical composition and ordering phenomena in CdSe/ZnSSe supperlattices were also investigated, employing a series of five-fold structures with different spacer layer thickness and a ten-fold structure. The composition in the CdSe/ZnSSe superlattice was determined to a certain extent using different techniques. Generally, the encountered difficulties regarding the accuracy of the obtained values are correlated with the complexity of the investigated system and with the available experimental methods used. Regarding the alignment of the dots, experimental results support a strain driven ordering process, in which the strain fields from buried dots lead to heterogeneous nucleation conditions for the dots in the subsequently deposited layers. An increased ordering with subsequent stacking of the dot layers is was also found. An anisotropy of the lateral alignment of the CdSe dots was also observed in two different left angle 110 right angle zone axes. The similar plan-view images shows that the preferential alignment of the dots does not follow low-index crystallographic directions. However, it is assumed that this is attributed to the anisotropic elastic strain distribution combined with surface diffusion. (orig.)

  18. Chitosan nanoparticles as non-viral gene delivery vehicles based on atomic force microscopy study

    Institute of Scientific and Technical Information of China (English)

    Yujing Yuan; Jieyi Tan; Yifei Wang; Chuiwen Qian; Meiying Zhang

    2009-01-01

    Chitosan (CS), a biocompatible and biodegradable material, can act as a non-viral delivery vehicle with low toxicity. In this study, plasmid DNA (pDNA) and siRNA were encapsulated in CS nanoparticles (NPs) to prepare CS-DNA and CS-siRNA NPs using a complex coacervation process. The CS-DNA particle size was within the range of 180-370 nm with a surface charge ranging from 0 to 18 mV at pH 5.5. The stability of pDNA in CS-DNA was investigated by pDNA release study and DNase I protection assay. The release of pDNA from NPs was studied in pH 7.4 phosphatebuffered saline at 37℃ and the CS-DNA NPs could delay the DNA release. Results of DNase I protection assay showed that CS-DNA NPs could protect the encapsulated pDNA from nuclease degradation. In the transfection study, it was found that the transfection efficiency in vitro was dependent on the molecular weight, charge ratio, and DNA concentration of the CS-DNA NP as well as the type of cell transfected. Moreover, the morphology of HeLa cells transfected with CS-siRNA complexes was studied using atomic force microscopy. The results suggest that CS may be more capable than liposome in delivering siRNA to target cells. In summary,our analysis suggests that pDNA and siRNA can be encapsulated in CS NPs without being damaged.

  19. Issues for application of virtual microscopy to cytoscreening, perspectives based on questionnaire to Japanese cytotechnologists.

    Science.gov (United States)

    Mori, Ichiro; Nunobiki, Osamu; Ozaki, Takashi; Taniguchi, Emiko; Kakudo, Kennichi

    2008-07-15

    To clarify the issues associated with the applications of virtual microscopy to the daily cytology slide screening, we conducted a survey at a slide conference of cytology. The survey was conducted specifically to the Japanese cytology technologists who use microscopes on a routine basis. Virtual slides (VS) were prepared from cytology slides using NanoZoomer (Hamamatsu Photonics, Japan), which is capable of adjusting focus on any part of the slide. A total of ten layers were scanned from the same slides, with 2 micrometer intervals. To simulate the cytology slide screening, no marker points were created. The total data volume of six slides was approximately 25 Giga Bytes. The slides were stored on the Windows 2003 Server, and were made accessible on the web to the cytology technologists. Most cytotechnologists answered "Satisfied" or "Acceptable" to the VS resolution and drawing speed, and "Dissatisfied" to the operation speed. To the ten layered focus, an answer "insufficient" was slightly more frequent than the answer "sufficient", while no one answered "fewer is acceptable" or "no need for depth". As for the use of cytology slide screening, answers "usable, but requires effort" and "not usable" were about equal in number. In a Japanese cytology meeting, a unique VS system has been used in slide conferences with markings to the discussion point for years. Therefore, Japanese cytotechnologists are relatively well accustomed to the use of VS, and the survey results showed that they regarded VS more positively than we expected. Currently, VS has the acceptable resolution and drawing speed even on the web. Most cytotechnologists regard the focusing capability crucial for cytology slide screening, but the consequential enlargement of data size, longer scanning time, and slower drawing speed are the issues that are yet to be resolved.

  20. Modeling of fibrin gels based on confocal microscopy and light-scattering data.

    Science.gov (United States)

    Magatti, Davide; Molteni, Matteo; Cardinali, Barbara; Rocco, Mattia; Ferri, Fabio

    2013-03-01

    Fibrin gels are biological networks that play a fundamental role in blood coagulation and other patho/physiological processes, such as thrombosis and cancer. Electron and confocal microscopies show a collection of fibers that are relatively monodisperse in diameter, not uniformly distributed, and connected at nodal points with a branching order of ∼3-4. Although in the confocal images the hydrated fibers appear to be quite straight (mass fractal dimension D(m) = 1), for the overall system 1, joined at randomly distributed nodal points. The resulting 3D network strikingly resembles real fibrin gels and can be sketched as an assembly of densely packed fractal blobs, i.e., regions of size ξ, where the fiber concentration is higher than average. The blobs are placed at a distance ξ0 between their centers of mass so that they are overlapped by a factor η =ξ/ξ0 and have D(m) ∼1.2-1.6. The in silico gels' structure is quantitatively analyzed by its 3D spatial correlation function g(3D)(r) and corresponding power spectrum I(q) = FFT(3D[g3D(r)]), from which ρ, d, D(m), η, and ξ0 can be extracted. In particular, ξ0 provides an excellent estimate of the gel mesh size. The in silico gels' I(q) compares quite well with real gels' elastic light-scattering measurements. We then derived an analytical form factor for accurately fitting the scattering data, which allowed us to directly recover the gels' structural parameters.

  1. Analysis of Adhesive Characteristics of Asphalt Based on Atomic Force Microscopy and Molecular Dynamics Simulation.

    Science.gov (United States)

    Xu, Meng; Yi, Junyan; Feng, Decheng; Huang, Yudong; Wang, Dongsheng

    2016-05-18

    Asphalt binder is a very important building material in infrastructure construction; it is commonly mixed with mineral aggregate and used to produce asphalt concrete. Owing to the large differences in physical and chemical properties between asphalt and aggregate, adhesive bonds play an important role in determining the performance of asphalt concrete. Although many types of adhesive bonding mechanisms have been proposed to explain the interaction forces between asphalt binder and mineral aggregate, few have been confirmed and characterized. In comparison with chemical interactions, physical adsorption has been considered to play a more important role in adhesive bonding between asphalt and mineral aggregate. In this study, the silicon tip of an atomic force microscope was used to represent silicate minerals in aggregate, and a nanoscale analysis of the characteristics of adhesive bonding between asphalt binder and the silicon tip was conducted via an atomic force microscopy (AFM) test and molecular dynamics (MD) simulations. The results of the measurements and simulations could help in better understanding of the bonding and debonding procedures in asphalt-aggregate mixtures during hot mixing and under traffic loading. MD simulations on a single molecule of a component of asphalt and monocrystalline silicon demonstrate that molecules with a higher atomic density and planar structure, such as three types of asphaltene molecules, can provide greater adhesive strength. However, regarding the real components of asphalt binder, both the MD simulations and AFM test indicate that the colloidal structural behavior of asphalt also has a large influence on the adhesion behavior between asphalt and silicon. A schematic model of the interaction between asphalt and silicon is presented, which can explain the effect of aging on the adhesion behavior of asphalt.

  2. Volumetric label-free imaging and 3D reconstruction of mammalian cochlea based on two-photon excitation fluorescence microscopy

    Science.gov (United States)

    Zhang, Xianzeng; Geng, Yang; Ye, Qing; Zhan, Zhenlin; Xie, Shusen

    2013-11-01

    The visualization of the delicate structure and spatial relationship of intracochlear sensory cells has relied on the laborious procedures of tissue excision, fixation, sectioning and staining for light and electron microscopy. Confocal microscopy is advantageous for its high resolution and deep penetration depth, yet disadvantageous due to the necessity of exogenous labeling. In this study, we present the volumetric imaging of rat cochlea without exogenous dyes using a near-infrared femtosecond laser as the excitation mechanism and endogenous two-photon excitation fluorescence (TPEF) as the contrast mechanism. We find that TPEF exhibits strong contrast, allowing cellular and even subcellular resolution imaging of the cochlea, differentiating cell types, visualizing delicate structures and the radial nerve fiber. Our results further demonstrate that 3D reconstruction rendered with z-stacks of optical sections enables better revealment of fine structures and spatial relationships, and easily performed morphometric analysis. The TPEF-based optical biopsy technique provides great potential for new and sensitive diagnostic tools for hearing loss or hearing disorders, especially when combined with fiber-based microendoscopy.

  3. Photothermal imaging scanning microscopy

    Science.gov (United States)

    Chinn, Diane; Stolz, Christopher J.; Wu, Zhouling; Huber, Robert; Weinzapfel, Carolyn

    2006-07-11

    Photothermal Imaging Scanning Microscopy produces a rapid, thermal-based, non-destructive characterization apparatus. Also, a photothermal characterization method of surface and subsurface features includes micron and nanoscale spatial resolution of meter-sized optical materials.

  4. Digital reconstruction based on angular spectrum diffraction with the ridge of wavelet transform in holographic phase-contrast microscopy.

    Science.gov (United States)

    Weng, Jiawen; Zhong, Jiangang; Hu, Cuiying

    2008-12-22

    A numerical reconstruction technique of digital holography based on angular spectrum diffraction by means of the ridge of Gabor wavelet transform (GWT) is presented. Appling the GWT, the object wave can be reconstructed by calculating the wavelet coefficients of the hologram at the ridge of the GWT automatically even if the spectrum of the virtual image is disturbed by the other spectrum. It provides a way to eliminate the effect of the zero-order and the twin-image terms without the spatial filtering. In particular, based on the angular spectrum theory, GWT is applied to the digital holographic phase-contrast microscopy on biological specimens. The theory, the results of a simulation and an experiment of an onion specimen are shown.

  5. It's Elementary: Expanding the Use of School-Based Clinics

    Science.gov (United States)

    Lear, Julia Graham

    2007-01-01

    Governor Arnold Schwarzenegger has declared his intention to open health centers in 500 elementary schools across the state, which would bring the total number of such school-based clinics to 646. This initiative builds on California's 30-year history of using the school setting to increase access to care for children, improve clinical outcomes,…

  6. Bayesian-based aberration correction and numerical diffraction for improved lensfree on-chip microscopy of biological specimens

    CERN Document Server

    Wong, Alexander; Jin, Chao; Wang, Xiao Yu

    2015-01-01

    Lensfree on-chip microscopy is an emerging imaging technique that can be used to visualize and study biological specimens without the need for imaging lens systems. Important issues that can limit the performance of lensfree on-chip microscopy include interferometric aberrations, acquisition noise, and image reconstruction artifacts. In this study, we introduce a Bayesian-based method for performing aberration correction and numerical diffraction that accounts for all three of these issues to improve the effective numerical aperture (NA) and signal-to-noise ratio (SNR) of the reconstructed microscopic image. The proposed method was experimentally validated using the USAF resolution target as well as real waterborne Anabaena flos-aquae samples, demonstrating improvements in NA by ~25% over the standard method, and improvements in SNR of 2.3 dB and 3.8 dB in the reconstructed image when compared to the reconstructed images produced using the standard method and a maximum likelihood estimation method, respective...

  7. Rapid on-site detection of airborne asbestos fibers and potentially hazardous nanomaterials using fluorescence microscopy-based biosensing.

    Science.gov (United States)

    Kuroda, Akio; Alexandrov, Maxym; Nishimura, Tomoki; Ishida, Takenori

    2016-06-01

    A large number of peptides with binding affinity to various inorganic materials have been identified and used as linkers, catalysts, and building blocks in nanotechnology and nanobiotechnology. However, there have been few applications of material-binding peptides in the fluorescence microscopy-based biosensing (FM method) of environmental pollutants. A notable exception is the application of the FM method for the detection of asbestos, a dangerous industrial toxin that is still widely used in many developing countries. This review details the selection and isolation of asbestos-binding proteins and peptides with sufficient specificity to distinguish asbestos from a large variety of safer fibrous materials used as asbestos substitutes. High sensitivity to nanoscale asbestos fibers (30-35 nm in diameter) invisible under conventional phase contrast microscopy can be achieved. The FM method is the basis for developing an automated system for asbestos biosensing that can be used for on-site testing with a portable fluorescence microscope. In the future, the FM method could also become a useful tool for detecting other potentially hazardous nanomaterials in the environment.

  8. Note: Tormenta: An open source Python-powered control software for camera based optical microscopy

    Science.gov (United States)

    Barabas, Federico M.; Masullo, Luciano A.; Stefani, Fernando D.

    2016-12-01

    Until recently, PC control and synchronization of scientific instruments was only possible through closed-source expensive frameworks like National Instruments' LabVIEW. Nowadays, efficient cost-free alternatives are available in the context of a continuously growing community of open-source software developers. Here, we report on Tormenta, a modular open-source software for the control of camera-based optical microscopes. Tormenta is built on Python, works on multiple operating systems, and includes some key features for fluorescence nanoscopy based on single molecule localization.

  9. Coherent anti-Stokes Raman scattering microscopy with a photonic crystal fiber based light source

    DEFF Research Database (Denmark)

    Paulsen, H.N.; Hilligsøe, Karen Marie; Thøgersen, J.;

    2003-01-01

    A coherent anti-Stokes Raman scattering microscope based on a Ti:sapphire femtosecond oscillator and a photonic crystal fiber is demonstrated. The nonlinear response of the fiber is used to generate the additional wavelength needed in the Raman process. The applicability of the setup...

  10. A piecewise monotone subgradient algorithm for accurate L¹-TV based registration of physical slices with discontinuities in microscopy.

    Science.gov (United States)

    Michalek, Jan; Capek, Martin

    2013-05-01

    Image registration tasks are often formulated in terms of minimization of a functional consisting of a data fidelity term penalizing the mismatch between the reference and the target image, and a term enforcing smoothness of shift between neighboring pairs of pixels (a min-sum problem). Most methods for deformable image registration use some form of interpolation between matching control points. The interpolation makes it impossible to account for isolated discontinuities in the deformation field that may appear, e.g., when a physical slice of a microscopy specimen is ruptured by the cutting tool. For registration of neighboring physical slices of microscopy specimens with discontinuities, Janácek proposed an L¹-distance data fidelity term and a total variation (TV) smoothness term, and used a graph-cut (GC) based iterative steepest descent algorithm for minimization. The L¹-TV functional is nonconvex; hence a steepest descent algorithm is not guaranteed to converge to the global minimum. Schlesinger presented transformation of max-sum problems to minimization of a dual quantity called problem power, which is--contrary to the original max-sum functional--convex. Based on Schlesinger's solution to max-sum problems we developed an algorithm for L¹-TV minimization by iterative multi-label steepest descent minimization of the convex dual problem. For Schlesinger's subgradient algorithm we proposed a novel step control heuristics that considerably enhances both speed and accuracy compared with standard step size strategies for subgradient methods. It is shown experimentally that our subgradient scheme achieves consistently better image registration than GC in terms of lower values both of the composite L¹-TV functional, and of its components, i.e., the L¹ distance of the images and the transformation smoothness TV, and yields visually acceptable results even in cases where the GC based algorithm fails. The new algorithm allows easy parallelization and can thus be

  11. High-speed real-time single-pixel microscopy based on Fourier sampling

    CERN Document Server

    Guo, Qiang; Wang, Yuxi; Guo, Yong; Liu, Peng; Zhu, Xiurui; Cheng, Zheng; Yu, Zhenming; Chen, Minghua; Yang, Sigang; Xie, Shizhong

    2016-01-01

    Single-pixel cameras based on the concepts of compressed sensing (CS) leverage the inherent structure of images to retrieve them with far fewer measurements and operate efficiently over a significantly broader spectral range than conventional silicon-based cameras. Recently, photonic time-stretch (PTS) technique facilitates the emergence of high-speed single-pixel cameras. A significant breakthrough in imaging speed of single-pixel cameras enables observation of fast dynamic phenomena. However, according to CS theory, image reconstruction is an iterative process that consumes enormous amounts of computational time and cannot be performed in real time. To address this challenge, we propose a novel single-pixel imaging technique that can produce high-quality images through rapid acquisition of their effective spatial Fourier spectrum. We employ phase-shifting sinusoidal structured illumination instead of random illumination for spectrum acquisition and apply inverse Fourier transform to the obtained spectrum fo...

  12. Web-based volume slicer for 3D electron-microscopy data from EMDB.

    Science.gov (United States)

    Salavert-Torres, José; Iudin, Andrii; Lagerstedt, Ingvar; Sanz-García, Eduardo; Kleywegt, Gerard J; Patwardhan, Ardan

    2016-05-01

    We describe the functionality and design of the Volume slicer - a web-based slice viewer for EMDB entries. This tool uniquely provides the facility to view slices from 3D EM reconstructions along the three orthogonal axes and to rapidly switch between them and navigate through the volume. We have employed multiple rounds of user-experience testing with members of the EM community to ensure that the interface is easy and intuitive to use and the information provided is relevant. The impetus to develop the Volume slicer has been calls from the EM community to provide web-based interactive visualisation of 2D slice data. This would be useful for quick initial checks of the quality of a reconstruction. Again in response to calls from the community, we plan to further develop the Volume slicer into a fully-fledged Volume browser that provides integrated visualisation of EMDB and PDB entries from the molecular to the cellular scale.

  13. Single cells and intracellular processes studied by a plasmonic-based electrochemical impedance microscopy

    Science.gov (United States)

    Wang, Wei; Foley, Kyle; Shan, Xiaonan; Wang, Shaopeng; Eaton, Seron; Nagaraj, Vinay J; Wiktor, Peter; Patel, Urmez; Tao, Nongjian

    2012-01-01

    We report an electrochemical impedance microscope (EIM) based on surface plasmon resonance. The new EIM can resolve local impedance with sub-micron spatial resolution, and monitor dynamics of various processes, such as apoptosis and electroporation of individual cells with millisecond time resolution. The high spatial and temporal resolution images make it possible to not only study individual cells, but also resolve the sub-cellular structures and processes without labels. The detection sensitivity achieved with the current setup is ~2 pS, which is excellent considering the conductance of a single ion channel is in the range of 5–400 pS. We describe also a model that simulates the EIM images of cells based on local dielectric constant and conductivity. PMID:21336333

  14. Investigation on traceability of 3D Scanning Electron Microscopy based on the Stereo Pair Technique

    DEFF Research Database (Denmark)

    Bariani, Paolo

    The scanning electron microscope (SEM) has a big potential as a metrology instrument for micro and nanotechnology due to its unique combination of three imaging properties: • Lateral ultimate resolution down to 2nm • Large range of possible magnification levels ranging from a few hundred times...... that addresses the performance of 3D topography calculation based on surface topography imaging using secondary electrons and the Stereo Pair Technique....

  15. Impact of thermal frequency drift on highest precision force microscopy using quartz-based force sensors at low temperatures

    Directory of Open Access Journals (Sweden)

    Florian Pielmeier

    2014-04-01

    Full Text Available In frequency modulation atomic force microscopy (FM-AFM the stability of the eigenfrequency of the force sensor is of key importance for highest precision force measurements. Here, we study the influence of temperature changes on the resonance frequency of force sensors made of quartz, in a temperature range from 4.8–48 K. The sensors are based on the qPlus and length extensional principle. The frequency variation with temperature T for all sensors is negative up to 30 K and on the order of 1 ppm/K, up to 13 K, where a distinct kink appears, it is linear. Furthermore, we characterize a new type of miniaturized qPlus sensor and confirm the theoretically predicted reduction in detector noise.

  16. Repeatability and reproducibility of intracellular molar concentration assessed by synchrotron-based x-ray fluorescence microscopy

    Science.gov (United States)

    Merolle, L.; Malucelli, E.; Fratini, M.; Gianoncelli, A.; Notargiacomo, A.; Cappadone, C.; Farruggia, G.; Sargenti, A.; Procopio, A.; Lombardo, M.; Lagomarsino, S.; Iotti, S.

    2016-01-01

    Elemental analysis of biological sample can give information about content and distribution of elements essential for human life or trace elements whose absence is the cause of abnormal biological function or development. However, biological systems contain an ensemble of cells with heterogeneous chemistry and elemental content; therefore, accurate characterization of samples with high cellular heterogeneity may only be achieved by analyzing single cells. Powerful methods in molecular biology are abundant, among them X-Ray microscopy based on synchrotron light source has gaining increasing attention thanks to its extremely sensitivity. However, reproducibility and repeatability of these measurements is one of the major obstacles in achieving a statistical significance in single cells population analysis. In this study, we compared the elemental content of human colon adenocarcinoma cells obtained by three distinct accesses to synchrotron radiation light.

  17. Repeatability and reproducibility of intracellular molar concentration assessed by synchrotron-based x-ray fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Merolle, L., E-mail: lucia.merolle@elettra.eu; Gianoncelli, A. [Elettra - Sincrotrone Trieste, 34149 Basovizza, Trieste (Italy); Malucelli, E., E-mail: emil.malucelli@unibo.it; Cappadone, C.; Farruggia, G.; Sargenti, A.; Procopio, A. [Department of Pharmacy and Biotechnology, University of Bologna, Bologna 40127 (Italy); Fratini, M. [Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Piazza del Viminale 1, 00184 Roma Italy (Italy); Department of Science, Roma Tre University, Via della Vasca Navale 84, I-00146 Rome (Italy); Notargiacomo, A. [Institute for Photonics and Nanotechnology, Consiglio Nazionale delle Richerche, 00156 Rome (Italy); Lombardo, M. [Department of Chemistry “G. Ciamician”, University of Bologna, Bologna 40126 (Italy); Lagomarsino, S. [Institute of Chemical-Physical Processes, Sapienza University of Rome, 00185 Rome (Italy); National Institute of Biostructures and Biosystems, 00136 Rome (Italy); Iotti, S. [Department of Pharmacy and Biotechnology, University of Bologna, Bologna 40127 (Italy); National Institute of Biostructures and Biosystems, 00136 Rome (Italy)

    2016-01-28

    Elemental analysis of biological sample can give information about content and distribution of elements essential for human life or trace elements whose absence is the cause of abnormal biological function or development. However, biological systems contain an ensemble of cells with heterogeneous chemistry and elemental content; therefore, accurate characterization of samples with high cellular heterogeneity may only be achieved by analyzing single cells. Powerful methods in molecular biology are abundant, among them X-Ray microscopy based on synchrotron light source has gaining increasing attention thanks to its extremely sensitivity. However, reproducibility and repeatability of these measurements is one of the major obstacles in achieving a statistical significance in single cells population analysis. In this study, we compared the elemental content of human colon adenocarcinoma cells obtained by three distinct accesses to synchrotron radiation light.

  18. Comparison of microscopy and Alamar blue reduction in a larval based assay for schistosome drug screening.

    Directory of Open Access Journals (Sweden)

    Nuha R Mansour

    Full Text Available BACKGROUND: In view of the current widespread use of and reliance on a single schistosomicide, praziquantel, there is a pressing need to discover and develop alternative drugs for schistosomiasis. One approach to this is to develop High Throughput in vitro whole organism screens (HTS to identify hits amongst large compound libraries. METHODOLOGY/PRINCIPAL FINDINGS: We have been carrying out low throughput (24-well plate in vitro testing based on microscopic evaluation of killing of ex-vivo adult S. mansoni worms using selected compound collections mainly provided through the WHO-TDR Helminth Drug Initiative. To increase throughput, we introduced a similar but higher throughput 96-well primary in vitro assay using the schistosomula stage which can be readily produced in vitro in large quantities. In addition to morphological readout of viability we have investigated using fluorometric determination of the reduction of Alamar blue (AB, a redox indicator of enzyme activity widely used in whole organism screening. A panel of 7 known schistosome active compounds including praziquantel, produced diverse effects on larval morphology within 3 days of culture although only two induced marked larval death within 7 days. The AB assay was very effective in detecting these lethal compounds but proved more inconsistent in detecting compounds which damaged but did not kill. The utility of the AB assay in detecting compounds which cause severe morbidity and/or death of schistosomula was confirmed in testing a panel of compounds previously selected in library screening as having activity against the adult worms. Furthermore, in prospective library screening, the AB assay was able to detect all compounds which induced killing and also the majority of compounds designated as hits based on morphological changes. CONCLUSION: We conclude that an HTS combining AB readout and image-based analysis would provide an efficient and stringent primary assay for schistosome

  19. [Research on WiFi-based wireless microscopy on a mobile phone and its application].

    Science.gov (United States)

    Hailan, Jin; Jing, Liu

    2012-11-01

    We proposed and realized a new device that acquires microscopic image wirelessly based on mobile phone and WiFi system. The mobile terminals could record, display and store the image from the far end via the wireless LAN. Using this system, a series of conceptual experiments on monitoring the microscopic images of common objects and liver cancer cells were successfully demonstrated. This system is expected to have important value in the experimental investigations on wirelessly monitoring the cell culture, and small insect etc.

  20. Arduino Due based tool to facilitate in vivo two-photon excitation microscopy.

    Science.gov (United States)

    Artoni, Pietro; Landi, Silvia; Sato, Sebastian Sulis; Luin, Stefano; Ratto, Gian Michele

    2016-04-01

    Two-photon excitation spectroscopy is a powerful technique for the characterization of the optical properties of genetically encoded and synthetic fluorescent molecules. Excitation spectroscopy requires tuning the wavelength of the Ti:sapphire laser while carefully monitoring the delivered power. To assist laser tuning and the control of delivered power, we developed an Arduino Due based tool for the automatic acquisition of high quality spectra. This tool is portable, fast, affordable and precise. It allowed studying the impact of scattering and of blood absorption on two-photon excitation light. In this way, we determined the wavelength-dependent deformation of excitation spectra occurring in deep tissues in vivo.

  1. Cantilevered bimorph-based scanner for high speed atomic force microscopy with large scanning range.

    Science.gov (United States)

    Zhou, Yusheng; Shang, Guangyi; Cai, Wei; Yao, Jun-en

    2010-05-01

    A cantilevered bimorph-based resonance-mode scanner for high speed atomic force microscope (AFM) imaging is presented. The free end of the bimorph is used for mounting a sample stage and the other one of that is fixed on the top of a conventional single tube scanner. High speed scanning is realized with the bimorph-based scanner vibrating at resonant frequency driven by a sine wave voltage applied to one piezolayer of the bimorph, while slow scanning is performed by the tube scanner. The other piezolayer provides information on vibration amplitude and phase of the bimorph itself simultaneously, which is used for real-time data processing and image calibration. By adjusting the free length of the bimorph, the line scan rate can be preset ranging from several hundred hertz to several kilohertz, which would be beneficial for the observation of samples with different properties. Combined with a home-made AFM system and a commercially available data acquisition card, AFM images of various samples have been obtained, and as an example, images of the silicon grating taken at a line rate of 1.5 kHz with the scan size of 20 microm are given. By manually moving the sample of polished Al foil surface while scanning, the capability of dynamic imaging is demonstrated.

  2. Pico-projector-based optical sectioning microscopy for 3D chlorophyll fluorescence imaging of mesophyll cells

    Science.gov (United States)

    Chen, Szu-Yu; Hsu, Yu John; Yeh, Chia-Hua; Chen, S.-Wei; Chung, Chien-Han

    2015-03-01

    A pico-projector-based optical sectioning microscope (POSM) was constructed using a pico-projector to generate structured illumination patterns. A net rate of 5.8 × 106 pixel/s and sub-micron spatial resolution in three-dimensions (3D) were achieved. Based on the pico-projector’s flexibility in pattern generation, the characteristics of POSM with different modulation periods and at different imaging depths were measured and discussed. With the application of different modulation periods, 3D chlorophyll fluorescence imaging of mesophyll cells was carried out in freshly plucked leaves of four species without sectioning or staining. For each leaf, an average penetration depth of 120 μm was achieved. Increasing the modulation period along with the increment of imaging depth, optical sectioning images can be obtained with a compromise between the axial resolution and signal-to-noise ratio. After ∼30 min imaging on the same area, photodamage was hardly observed. Taking the advantages of high speed and low damages of POSM, the investigation of the dynamic fluorescence responses to temperature changes was performed under three different treatment temperatures. The three embedded blue, green and red light-emitting diode light sources were applied to observe the responses of the leaves with different wavelength excitation.

  3. Respiratory clinical guidelines inform ward-based nurses' clinical skills and knowledge required for evidence-based care.

    Science.gov (United States)

    Johnson, Alisha M; Smith, Sheree M S

    2016-09-01

    Respiratory clinical guidelines provide clinicians with evidence-based guidance for practice. Clinical guidelines also provide an opportunity to identify the knowledge and technical and non-technical skills required by respiratory ward-based registered nurses. The aim of this review was to use a systematic process to establish the core technical and non-technical skills and knowledge identified in evidence-based clinical guidelines that enable the care of hospitalised adult respiratory patients. 17 guidelines were identified in our systematic review. The quality assessment demonstrated variability in these guidelines. Common core knowledge and technical and non-technical skills were identified. These include pathophysiology, understanding of physiological measurements and monitoring, education, counselling, and ward and patient management. The knowledge and skills extracted from respiratory clinical guidelines may inform a curriculum for ward-based respiratory nursing to ensure optimal care of adult patients.

  4. An Atomic Force Microscopy based investigation of specific biomechanical properties for various types of neuronal cells

    Science.gov (United States)

    Spedden, Elise; White, James; Kaplan, David; Staii, Cristian

    2012-02-01

    Here we describe the use of Atomic Force Microscope (AFM) based techniques to characterize and explore the influence of biochemical and biomechanical cues on the growth and interaction of neuronal cells with surrounding guidance factors. Specifically, we use AFM topography and AFM force spectroscopy measurements to systematically investigate the morphology, elasticity, and real time growth of neuronal processes in the presence of different types of extracellular matrix proteins and growth factors. We therefore create a series of systems containing specified neuron densities where the type of the underlying growth promoting protein is different from sample to sample. For each system we measure key biomechanical parameters related to neuronal growth such as height and elastic modulus at multiple growth points on several types of neurons. We show that systematic measurements of these parameters yield fundamental information about the role played by substrate-plated guidance factors in determining elastic and morphological properties of neurons during growth.

  5. Recognizing Disjoint Clinical Concepts in Clinical Text Using Machine Learning-based Methods

    Science.gov (United States)

    Tang, Buzhou; Chen, Qingcai; Wang, Xiaolong; Wu, Yonghui; Zhang, Yaoyun; Jiang, Min; Wang, Jingqi; Xu, Hua

    2015-01-01

    Clinical concept recognition (CCR) is a fundamental task in clinical natural language processing (NLP) field. Almost all current machine learning-based CCR systems can only recognize clinical concepts of consecutive words (called consecutive clinical concepts, CCCs), but can do nothing about clinical concepts of disjoint words (called disjoint clinical concepts, DCCs), which widely exist in clinical text. In this paper, we proposed two novel types of representations for disjoint clinical concepts, and applied two state-of-the-art machine learning methods to recognizing consecutive and disjoint concepts. Experiments conducted on the 2013 ShARe/CLEF challenge corpus showed that our best system achieved a “strict” F-measure of 0.803 for CCCs, a “strict” F-measure of 0.477 for DCCs, and a “strict” F-measure of 0.783 for all clinical concepts, significantly higher than the baseline systems by 4.2% and 4.1% respectively. PMID:26958258

  6. Community based clinical program: the Medunsa physiotherapy students` experience

    Directory of Open Access Journals (Sweden)

    N. P. Taukobong

    2004-02-01

    Full Text Available Backgound: The aim of community based clinical training is tproduce graduates who are responsive to the health needs of their communit It is envisaged that upon completion of training graduates would go back an serve their respective communities following exposure to community need Program evaluation should therefore allow students to express the inadequacie and strengths of the program.Aim: To evaluate the community-based clinical program through student's experiences.Methodology: A qualitative research design was used. End of block students reports for both third (8 and fourth (15 year physiotherapy students (n = 23 were used to collect the data. Responses in the reports were grouped into the following categories for purpose of data analysis: feeling about the block, suggestion/s and supervision.Results: The students described the community based clinical program as an unique learning experience which equipped them with the understanding of life within communities. Sixty five percent (65% expressed satisfaction with the supervision given. The main complaints were amounts of paper work involved and clinical workload.Conclusion: The student's experiences indicated that the community-based clinical program within the MEDUNSA physiotherapy department realizes the goal of community-based clinical training as determined by WHO, except for inclusion of some multi-professional approaches and adaptation of the supervision provided.

  7. Thermal conductivity calibration for hot wire based dc scanning thermal microscopy

    Science.gov (United States)

    Lefèvre, Stéphane; Volz, Sebastian; Saulnier, Jean-Bernard; Fuentes, Catherine; Trannoy, Nathalie

    2003-04-01

    Thermal conductivity characterization with nanoscale spatial resolution can be performed by contact probe techniques only. The technique based on a hot anemometer wire probe mounted in an atomic force microscope is now a standard setup. However, no rigorous calibration procedure is provided so far in basic dc mode. While in contact with the sample surface, the electrical current I injected into the probe is controlled so that electrical resistance or the wire temperature is maintained by the Joule effect. The variation in current is assumed to be linearly related to the heat flux lost towards the sample and traditional calibration is carried out by relating the thermal conductivity of a set of samples to the measured current I. We provide analytical and numerical thermal modeling of the tip and sample to estimate the key heat transfer in a conductivity calibration procedure. A simple calibration expression is established that provides thermal conductivity as a function of the probe current or voltage measured. Finally, experimental data allow us to determine the unknown quantities of the parametric form obtained, i.e., the mean tip-sample contact radius and conductance.

  8. Identification by microscopy and MS-based electronic nose of a fraudulent addition to maize gluten

    Directory of Open Access Journals (Sweden)

    Frick G.

    2009-01-01

    Full Text Available Classical and chemometric methods have been used to detect falsified maize gluten products. Microscopic observations (numerous starch grains, seed envelopes and wheat bran fragments clearly showed the presence of atypical maize gluten particles in samples with otherwise normal crude protein levels (≥ 60% and the usual gold-yellow color. Chemical analyses in a few samples confirmed the presence of urea (19 to 174 g.kg-1, melamine (0 to 20 g.kg-1, and cyanuric acid (0 to 10 g.kg-1 coping for the low levels of methionine (0 to 13 g.kg-1 in incriminated products (genuine maize gluten methionine level ≥ 16 g.kg-1. Furthermore, a fast technique (an electronic nose based on mass spectrometry detection also proved to be reliable for the identification of falsified maize gluten products: 100% correct classification of model and unknown samples was achieved with principal component analysis. As a consequence of these results, the Swiss feed-inspection authority blocked the import, or restricted the use, of 2,500 tons of the falsified products.

  9. Identification of novel pro-migratory, cancer-associated genes using quantitative, microscopy-based screening.

    Directory of Open Access Journals (Sweden)

    Suha Naffar-Abu-Amara

    Full Text Available BACKGROUND: Cell migration is a highly complex process, regulated by multiple genes, signaling pathways and external stimuli. To discover genes or pharmacological agents that can modulate the migratory activity of cells, screening strategies that enable the monitoring of diverse migratory parameters in a large number of samples are necessary. METHODOLOGY: In the present study, we describe the development of a quantitative, high-throughput cell migration assay, based on a modified phagokinetic tracks (PKT procedure, and apply it for identifying novel pro-migratory genes in a cancer-related gene library. In brief, cells are seeded on fibronectin-coated 96-well plates, covered with a monolayer of carboxylated latex beads. Motile cells clear the beads, located along their migratory paths, forming tracks that are visualized using an automated, transmitted-light screening microscope. The tracks are then segmented and characterized by multi-parametric, morphometric analysis, resolving a variety of morphological and kinetic features. CONCLUSIONS: In this screen we identified 4 novel genes derived from breast carcinoma related cDNA library, whose over-expression induces major alteration in the migration of the stationary MCF7 cells. This approach can serve for high throughput screening for novel ways to modulate cellular migration in pathological states such as tumor metastasis and invasion.

  10. EGFR mutations detection on liquid-based cytology: is microscopy still necessary?

    Science.gov (United States)

    Malapelle, Umberto; de Rosa, Nicla; Bellevicine, Claudio; Rocco, Danilo; Vitiello, Fabiana; Piantedosi, Franco Vito; Illiano, Alfonso; Nappi, Oscar; Troncone, Giancarlo

    2012-06-01

    Currently, there is a trend towards an increasing use of liquid-based cytology (LBC) to diagnose non-small cell lung cancer. In this study, to detect epidermal growth factor receptor mutations, different molecular techniques were applied to LBC samples with and without laser capture microdissection (LCM). In 58 LBCs, DNA was extracted twice. One sample was obtained directly from CytoLyt solution, whereas the other DNA sample was derived after slide preparation and LCM of Papanicolaou-stained cells. The rate of mutant cases obtained by direct sequencing was discordant between CytoLyt-derived (10.3%) and LCM-derived (17.2%) DNA. However, the same mutant rate (17.2%) was achieved on the matched samples by high-resolution melting analysis, fragment and TaqMan assays. Thus, LCM and direct sequencing may be replaced by more sensitive non-sequencing methods directly performed on CytoLyt-derived DNA, an easier and faster approach to improve epidermal growth factor receptor testing standardisation on LBCs.

  11. Image-Guided Cryoablation of the Spine in a Swine Model: Clinical, Radiological, and Pathological Findings with Light and Electron Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Ricardo Miguel Costa de, E-mail: ricardomcfreitas@gmail.com; Andrade, Celi Santos, E-mail: celis.andrade@hotmail.com; Caldas, José Guilherme Mendes Pereira, E-mail: jgmpcaldas@uol.com.br [Faculdade de Medicina da Universidade de São Paulo, Department of Radiology, Interventional Radiology Unit of the Instituto de Radiologia (Brazil); Tsunemi, Miriam Harumi, E-mail: miharumi@gmail.com [Universidade Estadual Paulista Júlio de Mesquita Filho, Department of Biostatistics, Biosciences Institute (Brazil); Ferreira, Lorraine Braga, E-mail: lorraine.braga@gmail.com; Arana-Chavez, Victor Elias, E-mail: vearana@usp.br [Faculdade de Odontologia da Universidade de São Paulo, Department of Oral Pathology (Brazil); Cury, Patrícia Maluf, E-mail: pmcury@hotmail.com [Faculdade de Medicina de São José do Rio Preto, Department of Pathology and Forensic Medicine (Brazil)

    2015-10-15

    PurposeThis study was designed to present the feasibility of an in vivo image-guided percutaneous cryoablation of the porcine vertebral body.MethodsThe institutional animal care committee approved this study. Cone-beam computed tomography (CBCT)-guided vertebral cryoablations (n = 22) were performed in eight pigs with short, 2-min, single or double-freezing protocols. Protective measures to nerves included dioxide carbon (CO{sub 2}) epidural injections and spinal canal temperature monitoring. Clinical, radiological, and pathological data with light (n = 20) or transmission electron (n = 2) microscopic analyses were evaluated after 6 days of clinical follow-up and euthanasia.ResultsCBCT/fluoroscopic-guided transpedicular vertebral body cryoprobe positioning and CO{sub 2} epidural injection were successful in all procedures. No major complications were observed in seven animals (87.5 %, n = 8). A minor complication was observed in one pig (12.5 %, n = 1). Logistic regression model analysis showed the cryoprobe-spinal canal (Cp-Sc) distance as the most efficient parameter to categorize spinal canal temperatures lower than 19 °C (p < 0.004), with a significant Pearson’s correlation test (p < 0.041) between the Cp-Sc distance and the lowest spinal canal temperatures. Ablation zones encompassed pedicles and the posterior wall of the vertebral bodies with an inflammatory rim, although no inflammatory infiltrate was depicted in the surrounding neural structures at light microscopy. Ultrastructural analyses evidenced myelin sheath disruption in some large nerve fibers, although neurological deficits were not observed.ConclusionsCBCT-guided vertebral cryoablation of the porcine spine is feasible under a combination of a short freezing protocol and protective measures to the surrounding nerves. Ultrastructural analyses may be helpful assess the early modifications of the nerve fibers.

  12. Evidence Based Dental Care: Integrating Clinical Expertise with Systematic Research

    OpenAIRE

    2014-01-01

    Clinical dentistry is becoming increasingly complex and our patients more knowledgeable. Evidence-based care is now regarded as the “gold standard” in health care delivery worldwide. The basis of evidence based dentistry is the published reports of research projects. They are, brought together and analyzed systematically in meta analysis, the source for evidence based decisions. Activities in the field of evidence-based dentistry has increased tremendously in the 21st century, more and more p...

  13. Semantically based clinical TCM telemedicine systems

    CERN Document Server

    Wong, Allan K Y; Lin, Wilfred W K; Dillon, Tharam S; Chang, Elizabeth J

    2015-01-01

    Recent years have seen the development of two significant trends namely: the adoption of some Traditional Chinese Medicine Practices into mainstream Allopathic Western Medicine and the advent of the internet and broad band networks leading to an increased interest in the use of Telemedicine to deliver medical services. In this book, we see the convergence of these two trends leading to a semantically-based TCM Telemedicine system that utilizes an ontology to provide sharable knowledge in the TCM realm to achieve this. The underpinning research required the development of a three-layer architecture and an Ontology of the TCM knowledge. As TCM knowledge like all medical knowledge is not frozen in time it was important to develop an approach that would allow evolution of the Ontology when new evidence became available. In order for the system to be practically grounded it was important to work with an industry partner PuraPharm Group/HerbMiners Informatics Limited. This partnership was initiated through Professo...

  14. Assessment of Clinical Competence: Written and Computer-Based Simulations.

    Science.gov (United States)

    Swanson, David B.; And Others

    1987-01-01

    Literature concerning the validity and reliability of both written and computer-based simulations in assessing clinical competence in the health professions is reviewed, and suggestions are given for the improvement of the psychometric qualities of simulation-based tests. (MSE)

  15. Applying extracellular vesicles based therapeutics in clinical trials

    DEFF Research Database (Denmark)

    Lener, Thomas; Gimona, Mario; Aigner, Ludwig

    2015-01-01

    EVs are considered the active drug components or primarily serve as drug delivery vehicles. For an effective and particularly safe translation of EV-based therapies into clinical practice, a high level of cooperation between researchers, clinicians and competent authorities is essential....... The translation of EVs into clinical therapies requires the categorization of EV-based therapeutics in compliance with existing regulatory frameworks. As the classification defines subsequent requirements for manufacturing, quality control and clinical investigation, it is of major importance to define whether....... In this position statement, basic and clinical scientists, as members of the International Society for Extracellular Vesicles (ISEV) and of the European Cooperation in Science and Technology (COST) program of the European Union, namely European Network on Microvesicles and Exosomes in Health and Disease (ME...

  16. Atomic force microscopy-based antibody recognition imaging of proteins in the pathological deposits in Pseudoexfoliation Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Creasey, Rhiannon [School of Chemical and Physical Sciences, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia); Sharma, Shiwani [School of Medicine, Ophthalmology, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia); Gibson, Christopher T. [School of Chemical and Physical Sciences, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia); Craig, Jamie E. [School of Medicine, Ophthalmology, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia); Ebner, Andreas [Institute for Biophysics, Johannes Kepler Universitaet Linz, Altenbergerstr. 69, A-4040 Linz (Austria); Becker, Thomas [Nanochemistry Research Institute, Curtin University, GPO Box U1987, Perth, 6845 WA (Australia); Hinterdorfer, Peter [Institute for Biophysics, Johannes Kepler Universitaet Linz, Altenbergerstr. 69, A-4040 Linz (Austria); Voelcker, Nicolas H., E-mail: nico.voelcker@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia)

    2011-07-15

    The phenomenon of protein aggregation is of considerable interest to various disciplines, including the field of medicine. A range of disease pathologies are associated with this phenomenon. One of the ocular diseases hallmarked by protein aggregation is the Pseudoexfoliation (PEX) Syndrome. This condition is characterized by the deposition of insoluble proteinaceous material on the anterior human lens capsule. Genomic and proteomic analyses have revealed an association of specific genetic markers and various proteins, respectively, with PEX syndrome. However, the ultrastructure of the protein aggregates is poorly characterized. This study seeks to build capacity to determine the molecular nature of PEX aggregates on human lens capsules in their native state by AFM-based antibody recognition imaging. Lysyl oxidase-Like 1 (LOXL1), a protein identified as a component of PEX aggregates, is detected by an antibody-modified AFM probe. Topographical AFM images and antibody recognition images are obtained using three AFM-based techniques: TREC, phase and force-volume imaging. LOXL1 is found to be present on the lens capsule surface, and is localized around fibrous protein aggregates. Our evaluation shows that TREC imaging is best suited for human tissue imaging and holds significant potential for imaging of human disease tissues in their native state. -- Highlights: {yields} Atomic force microscopy techniques were applied to diseased human tissues. {yields} LOXL1 protein was detected on the small fibers of Pseudoexfoliation deposits. {yields} PicoTREC was the optimum technique for investigating protein aggregates.

  17. StatSTEM: An efficient approach for accurate and precise model-based quantification of atomic resolution electron microscopy images.

    Science.gov (United States)

    De Backer, A; van den Bos, K H W; Van den Broek, W; Sijbers, J; Van Aert, S

    2016-12-01

    An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, has been investigated. The highest attainable precision is reached even for low dose images. Furthermore, the advantages of the model-based approach taking into account overlap between neighbouring columns are highlighted. This is done for the estimation of the distance between two neighbouring columns as a function of their distance and for the estimation of the scattering cross-section which is compared to the integrated intensity from a Voronoi cell. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license.

  18. Giant Electric-Field-Induced Strain in PVDF-Based Battery Separator Membranes Probed by Electrochemical Strain Microscopy.

    Science.gov (United States)

    Romanyuk, Konstantin; Costa, Carlos M; Luchkin, Sergey Yu; Kholkin, Andrei L; Lanceros-Méndez, Senentxu

    2016-05-31

    Efficiency of lithium-ion batteries largely relies on the performance of battery separator membrane as it controls the mobility and concentration of Li-ions between the anode and cathode electrodes. Recent advances in electrochemical strain microscopy (ESM) prompted the study of Li diffusion and transport at the nanoscale via electromechanical strain developed under an application of inhomogeneous electric field applied via the sharp ESM tip. In this work, we observed unexpectedly high electromechanical strain developed in polymer membranes based on porous poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-co-chlorotrifluoroethylene) (PVDF-CTFE) and, using it, could study a dynamics of electroosmotic flow of electrolyte inside the pores. We show that, independently of the separator membrane, electric field-induced deformation observed by ESM on wetted membrane surfaces can reach up to 10 nm under a moderate bias of 1 V (i.e., more than an order of magnitude higher than that in best piezoceramics). Such a high strain is explained by the electroosmotic flow in a porous media composed of PVDF. It is shown that the strain-based ESM method can be used to extract valuable information such as average pore size, porosity, elasticity of membrane in electrolyte solvent, and membrane-electrolyte affinity expressed in terms of zeta potential. Besides, such systems can, in principle, serve as actuators even in the absence of apparent piezoelectricity in amorphous PVDF.

  19. Synchrotron-based X-ray fluorescence microscopy enables multiscale spatial visualization of ions involved in fungal lignocellulose deconstruction

    Science.gov (United States)

    Kirker, Grant; Zelinka, Sam; Gleber, Sophie-Charlotte; Vine, David; Finney, Lydia; Chen, Si; Hong, Young Pyo; Uyarte, Omar; Vogt, Stefan; Jellison, Jody; Goodell, Barry; Jakes, Joseph E.

    2017-01-01

    The role of ions in the fungal decay process of lignocellulose biomaterials, and more broadly fungal metabolism, has implications for diverse research disciplines ranging from plant pathology and forest ecology, to carbon sequestration. Despite the importance of ions in fungal decay mechanisms, the spatial distribution and quantification of ions in lignocellulosic cell walls and fungal hyphae during decay is not known. Here we employ synchrotron-based X-ray fluorescence microscopy (XFM) to map and quantify physiologically relevant ions, such as K, Ca, Mn, Fe, and Zn, in wood being decayed by the model brown rot fungus Serpula lacrymans. Two-dimensional XFM maps were obtained to study the ion spatial distributions from mm to submicron length scales in wood, fungal hyphae with the dried extracellular matrix (ECM) from the fungus, and Ca oxalate crystals. Three-dimensional ion volume reconstructions were also acquired of wood cell walls and hyphae with ECM. Results show that the fungus actively transports some ions, such as Fe, into the wood and controls the distribution of ions at both the bulk wood and cell wall length scales. These measurements provide new insights into the movement of ions during decay and illustrate how synchrotron-based XFM is uniquely suited study these ions. PMID:28139778

  20. Synchrotron-based X-ray fluorescence microscopy enables multiscale spatial visualization of ions involved in fungal lignocellulose deconstruction

    Science.gov (United States)

    Kirker, Grant; Zelinka, Sam; Gleber, Sophie-Charlotte; Vine, David; Finney, Lydia; Chen, Si; Hong, Young Pyo; Uyarte, Omar; Vogt, Stefan; Jellison, Jody; Goodell, Barry; Jakes, Joseph E.

    2017-01-01

    The role of ions in the fungal decay process of lignocellulose biomaterials, and more broadly fungal metabolism, has implications for diverse research disciplines ranging from plant pathology and forest ecology, to carbon sequestration. Despite the importance of ions in fungal decay mechanisms, the spatial distribution and quantification of ions in lignocellulosic cell walls and fungal hyphae during decay is not known. Here we employ synchrotron-based X-ray fluorescence microscopy (XFM) to map and quantify physiologically relevant ions, such as K, Ca, Mn, Fe, and Zn, in wood being decayed by the model brown rot fungus Serpula lacrymans. Two-dimensional XFM maps were obtained to study the ion spatial distributions from mm to submicron length scales in wood, fungal hyphae with the dried extracellular matrix (ECM) from the fungus, and Ca oxalate crystals. Three-dimensional ion volume reconstructions were also acquired of wood cell walls and hyphae with ECM. Results show that the fungus actively transports some ions, such as Fe, into the wood and controls the distribution of ions at both the bulk wood and cell wall length scales. These measurements provide new insights into the movement of ions during decay and illustrate how synchrotron-based XFM is uniquely suited study these ions.

  1. In vivo determination of organellar pH using a universal wavelength-based confocal microscopy approach.

    Science.gov (United States)

    Pineda Rodó, Albert; Váchová, Libuše; Palková, Zdena

    2012-01-01

    Many essential cellular processes are affected by transmembrane H(+) gradients and intracellular pH (pHi). The research of such metabolic events calls for a non-invasive method to monitor pHi within individual subcellular compartments. We present a novel confocal microscopy approach for the determination of organellar pHi in living cells expressing pH-dependent ratiometric fluorescent proteins. Unlike conventional intensity-based fluorometry, our method relies on emission wavelength scans at single-organelle resolution to produce wavelength-based pH estimates both accurate and robust to low-signal artifacts. Analyses of Ato1p-pHluorin and Ato1p-mCherry yeast cells revealed previously unreported wavelength shifts in pHluorin emission which, together with ratiometric mCherry, allowed for high-precision quantification of actual physiological pH values and evidenced dynamic pHi changes throughout the different stages of yeast colony development. Additionally, comparative pH quantification of Ato1p-pHluorin and Met17p-pHluorin cells implied the existence of a significant pHi gradient between peripheral and internal cytoplasm of cells from colonies occurring in the ammonia-producing alkali developmental phase. Results represent a step forward in the study of pHi regulation and subcellular metabolic functions beyond the scope of this study.

  2. In vivo determination of organellar pH using a universal wavelength-based confocal microscopy approach.

    Directory of Open Access Journals (Sweden)

    Albert Pineda Rodó

    Full Text Available Many essential cellular processes are affected by transmembrane H(+ gradients and intracellular pH (pHi. The research of such metabolic events calls for a non-invasive method to monitor pHi within individual subcellular compartments. We present a novel confocal microscopy approach for the determination of organellar pHi in living cells expressing pH-dependent ratiometric fluorescent proteins. Unlike conventional intensity-based fluorometry, our method relies on emission wavelength scans at single-organelle resolution to produce wavelength-based pH estimates both accurate and robust to low-signal artifacts. Analyses of Ato1p-pHluorin and Ato1p-mCherry yeast cells revealed previously unreported wavelength shifts in pHluorin emission which, together with ratiometric mCherry, allowed for high-precision quantification of actual physiological pH values and evidenced dynamic pHi changes throughout the different stages of yeast colony development. Additionally, comparative pH quantification of Ato1p-pHluorin and Met17p-pHluorin cells implied the existence of a significant pHi gradient between peripheral and internal cytoplasm of cells from colonies occurring in the ammonia-producing alkali developmental phase. Results represent a step forward in the study of pHi regulation and subcellular metabolic functions beyond the scope of this study.

  3. 3D multiplexed immunoplasmonics microscopy

    Science.gov (United States)

    Bergeron, Éric; Patskovsky, Sergiy; Rioux, David; Meunier, Michel

    2016-07-01

    Selective labelling, identification and spatial distribution of cell surface biomarkers can provide important clinical information, such as distinction between healthy and diseased cells, evolution of a disease and selection of the optimal patient-specific treatment. Immunofluorescence is the gold standard for efficient detection of biomarkers expressed by cells. However, antibodies (Abs) conjugated to fluorescent dyes remain limited by their photobleaching, high sensitivity to the environment, low light intensity, and wide absorption and emission spectra. Immunoplasmonics is a novel microscopy method based on the visualization of Abs-functionalized plasmonic nanoparticles (fNPs) targeting cell surface biomarkers. Tunable fNPs should provide higher multiplexing capacity than immunofluorescence since NPs are photostable over time, strongly scatter light at their plasmon peak wavelengths and can be easily functionalized. In this article, we experimentally demonstrate accurate multiplexed detection based on the immunoplasmonics approach. First, we achieve the selective labelling of three targeted cell surface biomarkers (cluster of differentiation 44 (CD44), epidermal growth factor receptor (EGFR) and voltage-gated K+ channel subunit KV1.1) on human cancer CD44+ EGFR+ KV1.1+ MDA-MB-231 cells and reference CD44- EGFR- KV1.1+ 661W cells. The labelling efficiency with three stable specific immunoplasmonics labels (functionalized silver nanospheres (CD44-AgNSs), gold (Au) NSs (EGFR-AuNSs) and Au nanorods (KV1.1-AuNRs)) detected by reflected light microscopy (RLM) is similar to the one with immunofluorescence. Second, we introduce an improved method for 3D localization and spectral identification of fNPs based on fast z-scanning by RLM with three spectral filters corresponding to the plasmon peak wavelengths of the immunoplasmonics labels in the cellular environment (500 nm for 80 nm AgNSs, 580 nm for 100 nm AuNSs and 700 nm for 40 nm × 92 nm AuNRs). Third, the developed

  4. Workshop on the coupling of synchrotron radiation IR and X-rays with tip based scanning probe microscopies X-TIP

    Energy Technology Data Exchange (ETDEWEB)

    Comin, F.; Martinez-Criado, G.; Mundboth, K.; Susini, J. [European Synchrotron Radiation Facility (ESRF), 38 - Grenoble (France); Purans, J.; Sammelselg, V. [Tartu Univ. (Estonia); Chevrier, J.; Huant, S. [Universite Joseph-Fourier, Grenoble I, LEPES, 38 (France); Hamilton, B. [School of Electrical Engineering and Electronics, Manchester (United Kingdom); Saito, A. [Osaka Univ., RIKEN/SPring8 (Japan); Dhez, O. [OGG, INFM/CNR, 38 - Grenoble (France); Brocklesby, W.S. [Southampton Univ., Optoelectronics Research Centre (United Kingdom); Alvarez-Prado, L.M. [Ovieado, Dept. de Fisica (Spain); Kuzmin, A. [Institute of Solid State Physics - Riga (Latvia); Pailharey, D. [CRMC-N - CNRS, 13 - Marseille (France); Tonneau, D. [CRMCN - Faculte des sciences de Luminy, 13 - Marseille (France); Chretien, P. [Laboratoire de Genie Electrique de Paris, 75 - Paris (France); Cricenti, A. [ISM-CNR, Rome (Italy); DeWilde, Y. [ESPCI, 75 - Paris (France)

    2005-07-01

    The coupling of scanning probe microscopy (SPM) with synchrotron radiation is attracting increasing attention from nano-science community. By combining these 2 tools one can visualize, for example, the sample nano-structure prior to any X-ray characterization. Coupled with focusing devices or independently, SPM can provide spatial resolution below the optical limits. Furthermore, the possibility of employing SPM to manipulate nano-objects under X-ray beams is another exciting perspective. This document gathers the transparencies of 6 of the presentations made at the workshop: 1) the combination of atomic force microscopy and X-ray beam - experimental set-up and objectives; 2) the combination of scanning probe microscope and X-rays for detection of electrons; 3) towards soft X-ray scanning microscopy using tapered capillaries and laser-based high harmonic sources; 4) near-field magneto-optical microscopy; 5) near-field scanning optical microscopy - a brief overview -; and 6) from aperture-less near-field optical microscopy to infra-red near-field night vision. 4 posters entitled: 1) development of laboratory setup for X-ray/AFM experiments, 2) towards X-ray diffraction on single islands, 3) nano-XEOL using near-field detection, and 4) local collection with a STM tip of photoelectrons emitted by a surface irradiated by visible of UV laser beam, are included in the document.

  5. Evidence-Based Clinical Significance in Health Care: Toward an Inferential Analysis of Clinical Relevance

    Directory of Open Access Journals (Sweden)

    Mahsa Dousti

    2011-09-01

    Full Text Available Evidence-based dental practice requires the developmment and evaluation of protocols that en-sure translational effectiveness: that is, the efficient incorporation of the best available efficacy and effec-tiveness findings in specific clinical dentistry settings and environments. Evidence-based dentistry predi-cates the synthesis of research for obtaining the best available evidence in a validated, stringent, systematic and unbiased fashion. Research synthesis is now established as a science in its own right, precisely because it adheres to the scientific process that is driven by a research question and a hypothesis, follows through clearly defined methodology and design, yielding quantifiable data that are analyzed statistically, and from which stringent statistical inferences are drawn. The conclusions from the protocol of research synthesis define the best available evidence, which is used in the process of evidence-based revision of clinical practice guidelines. One important hurdle of the process of applying research synthesis in evidence-based dentistry lies in the fact that the statistical inferences produced by research must be translated into clinical relevance. Here, we present a model to circumvent this limitation by means of text analysis/mining protocols, which could lead the path toward a novel, valid and reliable ap-proach for the inferential analysis of clinical relevance.

  6. Fabrication and Demonstration of Mercury Disc-Well Probes for Stripping-Based Cyclic Voltammetry Scanning Electrochemical Microscopy.

    Science.gov (United States)

    Barton, Zachary J; Rodríguez-López, Joaquín

    2017-03-07

    Scanning electrochemical microscopy (SECM) is a rising technique for the study of energy storage materials. Hg-based probes allow the extension of SECM investigations to ionic processes, but the risk of irreversible Hg amalgam saturation limits their operation to rapid timescales and dilute analyte solutions. Here, we report a novel fabrication protocol for Hg disc-well ultramicroelectrodes (UMEs), which retain access to stripping information but are less susceptible to amalgam saturation than traditional Hg sphere-caps or thin-films. The amalgamation and stripping behaviors of Hg disc-well UMEs are compared to those of traditional Hg sphere-cap UMEs and corroborated with data from finite element simulations. The improved protection against amalgam saturation allows Hg disc-wells to operate safely in highly concentrated environments at long timescales. The utility of the probes for bulk measurements extends also to SECM studies, where the disc geometry facilitates small tip-substrate gaps and improves both spatial and temporal resolution. Because they can carry out slow, high-resolution anodic stripping voltammetry approaches and imaging in concentrated solutions, Hg disc-well electrodes fill a new analytical niche for studies of ionic reactivity and are a valuable addition to the electrochemical toolbox.

  7. In situ electron microscopy studies of electromechanical behavior in metals at the nanoscale using a novel microdevice-based system.

    Science.gov (United States)

    Kang, Wonmo; Beniam, Iyoel; Qidwai, Siddiq M

    2016-09-01

    Electrically assisted deformation (EAD) is an emerging technique to enhance formability of metals by applying an electric current through them. Despite its increasing importance in manufacturing applications, there is still an unresolved debate on the nature of the fundamental deformation mechanisms underlying EAD, mainly between electroplasticity (non-thermal effects) and resistive heating (thermal effects). This status is due to two critical challenges: (1) a lack of experimental techniques to directly observe fundamental mechanisms of material deformation during EAD, and (2) intrinsic coupling between electric current and Joule heating giving rise to unwanted thermally activated mechanisms. To overcome these challenges, we have developed a microdevice-based electromechanical testing system (MEMTS) to characterize nanoscale metal specimens in transmission electron microscopy (TEM). Our studies reveal that MEMTS eliminates the effect of Joule heating on material deformation, a critical advantage over macroscopic experiments, owing to its unique scale. For example, a negligible change in temperature (<0.02 °C) is predicted at ∼3500 A/mm(2). Utilizing the attractive features of MEMTS, we have directly investigated potential electron-dislocation interactions in single crystal copper (SCC) specimens that are simultaneously subjected to uniaxial loading and electric current density up to 5000 A/mm(2). Our in situ TEM studies indicate that for SCC, electroplasticity does not play a key role as no differences in dislocation activities, such as depinning and movement, are observed.

  8. In situ electron microscopy studies of electromechanical behavior in metals at the nanoscale using a novel microdevice-based system

    Science.gov (United States)

    Kang, Wonmo; Beniam, Iyoel; Qidwai, Siddiq M.

    2016-09-01

    Electrically assisted deformation (EAD) is an emerging technique to enhance formability of metals by applying an electric current through them. Despite its increasing importance in manufacturing applications, there is still an unresolved debate on the nature of the fundamental deformation mechanisms underlying EAD, mainly between electroplasticity (non-thermal effects) and resistive heating (thermal effects). This status is due to two critical challenges: (1) a lack of experimental techniques to directly observe fundamental mechanisms of material deformation during EAD, and (2) intrinsic coupling between electric current and Joule heating giving rise to unwanted thermally activated mechanisms. To overcome these challenges, we have developed a microdevice-based electromechanical testing system (MEMTS) to characterize nanoscale metal specimens in transmission electron microscopy (TEM). Our studies reveal that MEMTS eliminates the effect of Joule heating on material deformation, a critical advantage over macroscopic experiments, owing to its unique scale. For example, a negligible change in temperature (<0.02 °C) is predicted at ˜3500 A/mm2. Utilizing the attractive features of MEMTS, we have directly investigated potential electron-dislocation interactions in single crystal copper (SCC) specimens that are simultaneously subjected to uniaxial loading and electric current density up to 5000 A/mm2. Our in situ TEM studies indicate that for SCC, electroplasticity does not play a key role as no differences in dislocation activities, such as depinning and movement, are observed.

  9. Electron tomography of HEK293T cells using scanning electron microscope-based scanning transmission electron microscopy.

    Science.gov (United States)

    You, Yun-Wen; Chang, Hsun-Yun; Liao, Hua-Yang; Kao, Wei-Lun; Yen, Guo-Ji; Chang, Chi-Jen; Tsai, Meng-Hung; Shyue, Jing-Jong

    2012-10-01

    Based on a scanning electron microscope operated at 30 kV with a homemade specimen holder and a multiangle solid-state detector behind the sample, low-kV scanning transmission electron microscopy (STEM) is presented with subsequent electron tomography for three-dimensional (3D) volume structure. Because of the low acceleration voltage, the stronger electron-atom scattering leads to a stronger contrast in the resulting image than standard TEM, especially for light elements. Furthermore, the low-kV STEM yields less radiation damage to the specimen, hence the structure can be preserved. In this work, two-dimensional STEM images of a 1-μm-thick cell section with projection angles between ±50° were collected, and the 3D volume structure was reconstructed using the simultaneous iterative reconstructive technique algorithm with the TomoJ plugin for ImageJ, which are both public domain software. Furthermore, the cross-sectional structure was obtained with the Volume Viewer plugin in ImageJ. Although the tilting angle is constrained and limits the resulting structural resolution, slicing the reconstructed volume generated the depth profile of the thick specimen with sufficient resolution to examine cellular uptake of Au nanoparticles, and the final position of these nanoparticles inside the cell was imaged.

  10. GPU-based rapid reconstruction of cellular 3D refractive index maps from tomographic phase microscopy (Conference Presentation)

    Science.gov (United States)

    Dardikman, Gili; Shaked, Natan T.

    2016-03-01

    We present highly parallel and efficient algorithms for real-time reconstruction of the quantitative three-dimensional (3-D) refractive-index maps of biological cells without labeling, as obtained from the interferometric projections acquired by tomographic phase microscopy (TPM). The new algorithms are implemented on the graphic processing unit (GPU) of the computer using CUDA programming environment. The reconstruction process includes two main parts. First, we used parallel complex wave-front reconstruction of the TPM-based interferometric projections acquired at various angles. The complex wave front reconstructions are done on the GPU in parallel, while minimizing the calculation time of the Fourier transforms and phase unwrapping needed. Next, we implemented on the GPU in parallel the 3-D refractive index map retrieval using the TPM filtered-back projection algorithm. The incorporation of algorithms that are inherently parallel with a programming environment such as Nvidia's CUDA makes it possible to obtain real-time processing rate, and enables high-throughput platform for label-free, 3-D cell visualization and diagnosis.

  11. Compressive sensing based high-speed time-stretch optical microscopy for two-dimensional image acquisition.

    Science.gov (United States)

    Guo, Qiang; Chen, Hongwei; Weng, Zhiliang; Chen, Minghua; Yang, Sigang; Xie, Shizhong

    2015-11-16

    In this paper, compressive sensing based high-speed time-stretch optical microscopy for two-dimensional (2D) image acquisition is proposed and experimentally demonstrated for the first time. A section of dispersion compensating fiber (DCF) is used to perform wavelength-to-time conversion and then ultrafast spectral shaping of broadband optical pulses can be achieved via high-speed intensity modulation. A 2D spatial disperser comprising a pair of orthogonally oriented dispersers is employed to produce spatially structured illumination for 2D image acquisition and a section of single mode fiber (SMF) is utilized for pulse compression in the optical domain. In our scheme, a 1.2-GHz photodetector and a 50-MHz analog-to-digital converter (ADC) are used to acquire the energy of the compressed pulses. Image reconstructions are demonstrated at a frame rate of 500 kHz and a sixteen-fold image compression is achieved in our proof-of-concept demonstration.

  12. Super-resolved image acquisition with full-field localization-based microscopy: theoretical analysis and evaluation

    Science.gov (United States)

    Son, Taehwang; Lee, Wonju; Kim, Donghyun

    2016-02-01

    We analyze and evaluate super-resolved image acquisition with full-field localization microscopy in which an individual signal sampled by localization may or may not be switched. For the analysis, Nyquist-Shannon sampling theorem based on ideal delta function was extended to sampling with unit pulse comb and surface-enhanced localized near-field that was numerically calculated with finite difference time domain. Sampling with unit pulse was investigated in Fourier domain where magnitude of baseband becomes larger than that of adjacent subband, i.e. aliasing effect is reduced owing to pulse width. Standard Lena image was employed as imaging target and a diffraction-limited optical system is assumed. A peak signal-to-noise ratio (PSNR) was introduced to evaluate the efficiency of image reconstruction quantitatively. When the target was sampled without switching by unit pulse as the sampling width and period are varied, PSNR increased eventually to 18.1 dB, which is the PSNR of a conventional diffraction-limited image. PSNR was found to increase with a longer pulse width due to reduced aliasing effect. When switching of individual sampling pulses was applied, blurry artifact outside the excited field is removed for each pulse and PSNR soars to 25.6 dB with a shortened pulse period, i.e. effective resolution of 72 nm is obtained, which can further be decreased.

  13. Determination of electrostatic force and its characteristics based on phase difference by amplitude modulation atomic force microscopy

    Science.gov (United States)

    Wang, Kesheng; Cheng, Jia; Yao, Shiji; Lu, Yijia; Ji, Linhong; Xu, Dengfeng

    2016-12-01

    Electrostatic force measurement at the micro/nano scale is of great significance in science and engineering. In this paper, a reasonable way of applying voltage is put forward by taking an electrostatic chuck in a real integrated circuit manufacturing process as a sample, applying voltage in the probe and the sample electrode, respectively, and comparing the measurement effect of the probe oscillation phase difference by amplitude modulation atomic force microscopy. Based on the phase difference obtained from the experiment, the quantitative dependence of the absolute magnitude of the electrostatic force on the tip-sample distance and applied voltage is established by means of theoretical analysis and numerical simulation. The results show that the varying characteristics of the electrostatic force with the distance and voltage at the micro/nano scale are similar to those at the macroscopic scale. Electrostatic force gradually decays with increasing distance. Electrostatic force is basically proportional to the square of applied voltage. Meanwhile, the applicable conditions of the above laws are discussed. In addition, a comparison of the results in this paper with the results of the energy dissipation method shows the two are consistent in general. The error decreases with increasing distance, and the effect of voltage on the error is small.

  14. Fuzzy-Logic Based Detection and Characterization of Junctions and Terminations in Fluorescence Microscopy Images of Neurons.

    Science.gov (United States)

    Radojević, Miroslav; Smal, Ihor; Meijering, Erik

    2016-04-01

    Digital reconstruction of neuronal cell morphology is an important step toward understanding the functionality of neuronal networks. Neurons are tree-like structures whose description depends critically on the junctions and terminations, collectively called critical points, making the correct localization and identification of these points a crucial task in the reconstruction process. Here we present a fully automatic method for the integrated detection and characterization of both types of critical points in fluorescence microscopy images of neurons. In view of the majority of our current studies, which are based on cultured neurons, we describe and evaluate the method for application to two-dimensional (2D) images. The method relies on directional filtering and angular profile analysis to extract essential features about the main streamlines at any location in an image, and employs fuzzy logic with carefully designed rules to reason about the feature values in order to make well-informed decisions about the presence of a critical point and its type. Experiments on simulated as well as real images of neurons demonstrate the detection performance of our method. A comparison with the output of two existing neuron reconstruction methods reveals that our method achieves substantially higher detection rates and could provide beneficial information to the reconstruction process.

  15. Theoretical and experimental studies of distance dependent response of micro-ring resonator-based ultrasonic detectors for photoacoustic microscopy.

    Science.gov (United States)

    Zhang, Zhen; Dong, Biqin; Li, Hao; Zhou, Fan; Zhang, Hao F; Sun, Cheng

    2014-10-14

    We present in this paper a systematic study of the distance dependent detection characteristics of the newly developed micro-ring resonator (MRR)-based ultrasonic detector for photoacoustic microscopy (PAM). A simple analytic model was first developed to study the steady-state response to the continuous ultrasonic waves. While placing the MRR detector at the acoustic far-field provides longer working distance and broader field of view, the detection at acoustic near-field offers the improved sensitivity and broader bandwidth but at the cost of reduction in the field of view. Furthermore, a numerical model was developed to analyze the transient response to the photoacoustic-induced impulsive waves. Notably, far-field detection exhibits a flat wavefront of its response pattern in the time domain while large distortions are clearly visible in the case of near-field detection. Finally, both analytic and numerical models are validated by experimental studies. This work establishes a theoretical framework for quantitatively analyzing the trade-offs between near-field and far-field detection using MRR detector, creating a guideline for optimizing the PAM for various applications in biomedical imaging and diagnostics.

  16. Immobilization of zebrafish larvae on a chip-based device for environmental scanning electron microscopy (ESEM) imaging

    Science.gov (United States)

    Akagi, Jin; Hall, Chris J.; Crosier, Kathryn E.; Crosier, Philip S.; Wlodkowic, Donald

    2013-12-01

    Small vertebrate model organisms have recently gained popularity as attractive experimental models that enhance our understanding of human tissue and organ development. Laser microsurgery on zebrafish larvae combined with Scanning Electron Microscopy (SEM) imaging can in particular provide accelerated insights into the tissue regeneration phenomena. Conventional SEM exposes, however, specimens to high vacuum environments, and often requires laborintensive and time-consuming pretreatments and manual positioning. Moreover, there are virtually no technologies available that can quickly immobilize the zebrafish larvae for high definition SEM imaging. This work describes the proof-of-concept design and validation of a microfluidic chip-based system for immobilizing zebrafish larvae and it's interfacing with Environmental Scanning Electron Microscope (ESEM) imaging. The Lab-on-a-Chip (LOC) device was fabricated using a high-speed infrared laser micromachining and consists of a reservoir with multiple semispherical microwells, which hold the yolk of zebrafish larvae, and drain channels that allow removing excess of medium during SEM imaging. Paper filter is used to actuate the chip and immobilization of the larvae by gentle suction that occurs during water drainage. The trapping region allows multiple specimens to be positioned on the chip. The device is then inserted directly inside the ESEM and imaged in a near 100% humidity atmosphere. This facilitates ESEM imaging of untreated biological samples.

  17. Confocal microscopy-based three-dimensional cell-specific modeling for large deformation analyses in cellular mechanics.

    Science.gov (United States)

    Slomka, Noa; Gefen, Amit

    2010-06-18

    This study introduces a new confocal microscopy-based three-dimensional cell-specific finite element (FE) modeling methodology for simulating cellular mechanics experiments involving large cell deformations. Three-dimensional FE models of undifferentiated skeletal muscle cells were developed by scanning C2C12 myoblasts using a confocal microscope, and then building FE model geometries from the z-stack images. Strain magnitudes and distributions in two cells were studied when the cells were subjected to compression and stretching, which are used in pressure ulcer and deep tissue injury research to induce large cell deformations. Localized plasma membrane and nuclear surface area (NSA) stretches were observed for both the cell compression and stretching simulation configurations. It was found that in order to induce large tensile strains (>5%) in the plasma membrane and NSA, one needs to apply more than approximately 15% of global cell deformation in cell compression tests, or more than approximately 3% of tensile strains in the elastic plate substrate in cell stretching experiments. Utilization of our modeling can substantially enrich experimental cellular mechanics studies in classic cell loading designs that typically involve large cell deformations, such as static and cyclic stretching, cell compression, micropipette aspiration, shear flow and hydrostatic pressure, by providing magnitudes and distributions of the localized cellular strains specific to each setup and cell type, which could then be associated with the applied stimuli.

  18. Light sheet-based fluorescence microscopy (LSFM) reduces phototoxic effects and provides new means for the modern life sciences

    Science.gov (United States)

    Pampaloni, Francesco; Ansari, Nari; Girard, Philippe; Stelzer, Ernst H. K.

    2011-07-01

    Most optical technologies are applied to flat, basically two-dimensional cellular systems. However, physiological meaningful information relies on the morphology, the mechanical properties and the biochemistry of a cell's context. A cell requires the complex three-dimensional relationship to other cells. However, the observation of multi-cellular biological specimens remains a challenge. Specimens scatter and absorb light, thus, the delivery of the probing light and the collection of the signal light become inefficient; many endogenous biochemical compounds also absorb light and suffer degradation of some sort (photo-toxicity), which induces malfunction of a specimen. In conventional and confocal fluorescence microscopy, whenever a single plane, the entire specimen is illuminated. Recording stacks of images along the optical Z-axis thus illuminates the entire specimen once for each plane. Hence, cells are illuminated 10-20 and fish 100-300 times more often than they are observed. This can be avoided by changing the optical arrangement. The basic idea is to use light sheets, which are fed into the specimen from the side and overlap with the focal plane of a wide-field fluorescence microscope. In contrast to an epi-fluorescence arrangement, such an azimuthal fluorescence arrangement uses two independently operated lenses for illumination and detection. Optical sectioning and no photo-toxic damage or photo-bleaching outside a small volume close to the focal plane are intrinsic properties. Light sheet-based fluorescence microscopy (LSFM) takes advantage of modern camera technologies. LSFM can be operated with laser cutters and for fluorescence correlation spectroscopy. During the last few years, LSFM was used to record zebrafish development from the early 32-cell stage until late neurulation with sub-cellular resolution and short sampling periods (60-90 sec/stack). The recording speed was five 4-Megapixel large frames/sec with a dynamic range of 12-14 bit. We followed

  19. Clinical consequences of PCR based diagnosis of intestinal parasitic infections

    NARCIS (Netherlands)

    Rijsman, Lucas H; Monkelbaan, Jan F; Kusters, Johannes G

    2016-01-01

    The implementation of Polymerase Chain Reaction (PCR) based diagnostics of intestinal protozoa have led to higher sensitivity and (subtype) specificity, more convenient sampling and the possibility for high-throughput screening. An increasing number of clinical laboratories use PCR for routine detec

  20. Embedding trials in evidence-based clinical practice

    NARCIS (Netherlands)

    Oude Rengerink, K.

    2014-01-01

    This thesis presents a number of research projects centred on ‘evidence-based medicine’. It consists of two parts. Part 1 focuses on improving recruitment of the necessary number of patients in clinical trials, as this is the major problem while evaluating the effectiveness of interventions in healt

  1. Toward clinical scholarship: promoting evidence-based practice in the clinical setting.

    Science.gov (United States)

    Mohide, E Ann; Coker, Esther

    2005-01-01

    Organizational interventions are being suggested to increase the rate of quality research dissemination and uptake. This article describes how one tertiary institution is using an evidence-based nursing (EBN) committee as an organizational strategy to shift its nursing culture toward clinical scholarship. A number of approaches and activities that have stimulated the movement toward evidence-based practice (EBP) are examined: organizational commitment to EBP, strategic positioning of the EBN committee within nursing's administrative structure, articulation of a mission, conceptualization of a model for EBN practice, learning on the job, selection and adoption of an evidence-based model for implementing change, marketing for a change in culture toward clinical scholarship, and other selected examples of projects undertaken by the committee. Action-oriented principles associated with committee experiences are related to the approaches and activities.

  2. A new approach for the spatially resolved qualitative analysis of the protein distribution in hydrogel beads based on confocal laser scanning microscopy

    NARCIS (Netherlands)

    Heinemann, Matthias; Wagner, Thomas; Doumèche, Bastien; Ansorge-Schumacher, Marion; Büchs, Jochen

    2002-01-01

    To investigate the spatial distribution of white egg albumin (WEA) in alginate beads, a new method based on confocal laser scanning microscopy (CLSM) was developed. In contrast to the existing CLSM methods, misleading conclusions are prevented with the application of the new method which does not al

  3. Evidence-based integrative medicine in clinical veterinary oncology.

    Science.gov (United States)

    Raditic, Donna M; Bartges, Joseph W

    2014-09-01

    Integrative medicine is the combined use of complementary and alternative medicine with conventional or traditional Western medicine systems. The demand for integrative veterinary medicine is growing, but evidence-based research on its efficacy is limited. In veterinary clinical oncology, such research could be translated to human medicine, because veterinary patients with spontaneous tumors are valuable translational models for human cancers. An overview of specific herbs, botanics, dietary supplements, and acupuncture evaluated in dogs, in vitro canine cells, and other relevant species both in vivo and in vitro is presented for their potential use as integrative therapies in veterinary clinical oncology.

  4. Confocal scanning microscopy

    DEFF Research Database (Denmark)

    Bariani, Paolo

    This report is based on a metrological investigation on confocal microscopy technique carried out by Uffe Rolf Arlø Theilade and Paolo Bariani. The purpose of the experimental activity was twofold a metrological instrument characterization and application to assessment of rough PP injection moulded...... replicated topography. Confocal microscopy is seen to be a promising technique in metrology of microstructures. Some limitations with respect to surface metrology were found during the experiments. The experiments were carried out using a Zeiss LSM 5 Pascal microscope owned by the Danish Polymer Centre...

  5. Conventional transmission electron microscopy.

    Science.gov (United States)

    Winey, Mark; Meehl, Janet B; O'Toole, Eileen T; Giddings, Thomas H

    2014-02-01

    Researchers have used transmission electron microscopy (TEM) to make contributions to cell biology for well over 50 years, and TEM continues to be an important technology in our field. We briefly present for the neophyte the components of a TEM-based study, beginning with sample preparation through imaging of the samples. We point out the limitations of TEM and issues to be considered during experimental design. Advanced electron microscopy techniques are listed as well. Finally, we point potential new users of TEM to resources to help launch their project.

  6. Adhesion of rice flour-based batter to chicken drumsticks evaluated by laser scanning confocal microscopy and texture analysis.

    Science.gov (United States)

    Mukprasirt, A; Herald, T J; Boyle, D L; Rausch, K D

    2000-09-01

    The convenience and appeal of battered or breaded products have resulted in a sales increase of 100% since 1980. Because of the rapid growth of the Asian-American population and increasing consumption of rice and rice products, rice flour is a logical alternative for wheat flour in traditional batter formulation. The effects of ingredients used in rice flour-based batters on adhesion characteristic for deep-fat fried chicken drumsticks were studied by laser scanning confocal microscopy (LSCM) and texture analysis. Raw chicken drumsticks were predusted with egg albumin powder before dipping into batters prepared from combinations of rice flour, yellow corn flour, oxidized cornstarch, methylcellulose, or xanthan gum. The drumsticks were fried at 175+/-5 C until the internal temperature reached at least 71 C. For LSCM, samples were fixed overnight and were sectioned by vibratome (200 microm) before viewing. Batter adhesion was determined using an attachment specifically designed for chicken drumsticks. Microstructural analysis showed that batter formulated with a 50:50 mixture of rice and corn flours adhered better to drumsticks than batter with other rice flour ratios. Xanthan gum (0.2%) or methylcellulose (0.3%) alone had poor adhesion to chicken skin. However, when combined with other ingredients, xanthan gum increased the amount of batter pick-up before frying by increasing viscosity. Egg albumin significantly facilitated batter adhesion. The results from texture analysis supported the microstructural studies. As rice flour ratio increased from 50 to 70%, the binding force decreased. Rice flour showed potential as an alternative to wheat flour for batter formulas when the appropriate levels of oxidized starch, xanthan gum, and methylcellulose were included in the formulation.

  7. Discrimination Between Cervical Cancer Cells and Normal Cervical Cells Based on Longitudinal Elasticity Using Atomic Force Microscopy

    Science.gov (United States)

    Zhao, Xueqin; Zhong, Yunxin; Ye, Ting; Wang, Dajing; Mao, Bingwei

    2015-12-01

    The mechanical properties of cells are considered promising biomarkers for the early diagnosis of cancer. Recently, atomic force microscopy (AFM)-based nanoindentation technology has been utilized for the examination of cell cortex mechanics in order to distinguish malignant cells from normal cells. However, few attempts to evaluate the biomechanical properties of cells have focused on the quantification of the non-homogeneous longitudinal elasticity of cellular structures. In the present study, we applied a variation of the method of Carl and Schillers to investigate the differences between longitudinal elasticity of human cervical squamous carcinoma cells (CaSki) and normal cervical epithelial cells (CRL2614) using AFM. The results reveal a three-layer heterogeneous structure in the probing volume of both cell types studied. CaSki cells exhibited a lower whole-cell stiffness and a softer nuclei zone compared to the normal counterpart cells. Moreover, a better differentiated cytoskeleton was found in the inner cytoplasm/nuclei zone of the normal CRL2614 cells, whereas a deeper cytoskeletal distribution was observed in the probing volume of the cancerous counterparts. The sensitive cortical panel of CaSki cells, with a modulus of 0.35~0.47 kPa, was located at 237~225 nm; in normal cells, the elasticity was 1.20~1.32 kPa at 113~128 nm. The present improved method may be validated using the conventional Hertz-Sneddon method, which is widely reported in the literature. In conclusion, our results enable the quantification of the heterogeneous longitudinal elasticity of cancer cells, in particular the correlation with the corresponding depth. Preliminary results indicate that our method may potentially be applied to improve the detection of cancerous cells and provide insights into the pathophysiology of the disease.

  8. SynapticDB, effective web-based management and sharing of data from serial section electron microscopy.

    Science.gov (United States)

    Shi, Bitao; Bourne, Jennifer; Harris, Kristen M

    2011-03-01

    Serial section electron microscopy (ssEM) is rapidly expanding as a primary tool to investigate synaptic circuitry and plasticity. The ultrastructural images collected through ssEM are content rich and their comprehensive analysis is beyond the capacity of an individual laboratory. Hence, sharing ultrastructural data is becoming crucial to visualize, analyze, and discover the structural basis of synaptic circuitry and function in the brain. We devised a web-based management system called SynapticDB (http://synapses.clm.utexas.edu/synapticdb/) that catalogues, extracts, analyzes, and shares experimental data from ssEM. The management strategy involves a library with check-in, checkout and experimental tracking mechanisms. We developed a series of spreadsheet templates (MS Excel, Open Office spreadsheet, etc) that guide users in methods of data collection, structural identification, and quantitative analysis through ssEM. SynapticDB provides flexible access to complete templates, or to individual columns with instructional headers that can be selected to create user-defined templates. New templates can also be generated and uploaded. Research progress is tracked via experimental note management and dynamic PDF forms that allow new investigators to follow standard protocols and experienced researchers to expand the range of data collected and shared. The combined use of templates and tracking notes ensures that the supporting experimental information is populated into the database and associated with the appropriate ssEM images and analyses. We anticipate that SynapticDB will serve future meta-analyses towards new discoveries about the composition and circuitry of neurons and glia, and new understanding about structural plasticity during development, behavior, learning, memory, and neuropathology.

  9. Bacteriophage- based tests for the detection of Mycobacterium tuberculosis in clinical specimens: a systematic review and meta- analysis

    Directory of Open Access Journals (Sweden)

    Pascopella Lisa

    2005-07-01

    Full Text Available Abstract Background Sputum microscopy, the most important conventional test for tuberculosis, is specific in settings with high burden of tuberculosis and low prevalence of non tuberculous mycobacteria. However, the test lacks sensitivity. Although bacteriophage-based tests for tuberculosis have shown promising results, their overall accuracy has not been systematically evaluated. Methods We did a systematic review and meta-analysis of published studies to evaluate the accuracy of phage-based tests for the direct detection of M. tuberculosis in clinical specimens. To identify studies, we searched Medline, EMBASE, Web of science and BIOSIS, and contacted authors, experts and test manufacturers. Thirteen studies, all based on phage amplification method, met our inclusion criteria. Overall accuracy was evaluated using forest plots, summary receiver operating (SROC curves, and subgroup analyses. Results The data suggest that phage-based assays have high specificity (range 0.83 to 1.00, but modest and variable sensitivity (range 0.21 to 0.88. The sensitivity ranged between 0.29 and 0.87 among smear-positive, and 0.13 to 0.78 among smear-negative specimens. The specificity ranged between 0.60 and 0.88 among smear-positive and 0.89 to 0.99 among smear-negative specimens. SROC analyses suggest that overall accuracy of phage-based assays is slightly higher than smear microscopy in direct head-to-head comparisons. Conclusion Phage-based assays have high specificity but lower and variable sensitivity. Their performance characteristics are similar to sputum microscopy. Phage assays cannot replace conventional diagnostic tests such as microscopy and culture at this time. Further research is required to identify methods that can enhance the sensitivity of phage-based assays without compromising the high specificity.

  10. Development of a laser-based heating system for in situ synchrotron-based X-ray tomographic microscopy.

    Science.gov (United States)

    Fife, Julie L; Rappaz, Michel; Pistone, Mattia; Celcer, Tine; Mikuljan, Gordan; Stampanoni, Marco

    2012-05-01

    Understanding the formation of materials at elevated temperatures is critical for determining their final properties. Synchrotron-based X-ray tomographic microscopy is an ideal technique for studying such processes because high spatial and temporal resolutions are easily achieved and the technique is non-destructive, meaning additional analyses can take place after data collection. To exploit the state-of-the-art capabilities at the tomographic microscopy and coherent radiology experiments (TOMCAT) beamline of the Swiss Light Source, a general-use moderate-to-high-temperature furnace has been developed. Powered by two diode lasers, it provides controlled localized heating, from 673 to 1973 K, to examine many materials systems and their dynamics in real time. The system can also be operated in various thermal modalities. For example, near-isothermal conditions at a given sample location can be achieved with a prescribed time-dependent temperature. This mode is typically used to study isothermal phase transformations; for example, the formation of equiaxed grains in metallic systems or to nucleate and grow bubble foams in silicate melts under conditions that simulate volcanic processes. In another mode, the power of the laser can be fixed and the specimen moved at a constant speed in a user-defined thermal gradient. This is similar to Bridgman solidification, where the thermal gradient and cooling rate control the microstructure formation. This paper details the experimental set-up and provides multiple proofs-of-concept that illustrate the versatility of using this laser-based heating system to explore, in situ, many elevated-temperature phenomena in a variety of materials.

  11. Bases for time-resolved probing of transient carrier dynamics by optical pump-probe scanning tunneling microscopy.

    Science.gov (United States)

    Yokota, Munenori; Yoshida, Shoji; Mera, Yutaka; Takeuchi, Osamu; Oigawa, Haruhiro; Shigekawa, Hidemi

    2013-10-07

    The tangled mechanism that produces optical pump-probe scanning tunneling microscopy spectra from semiconductors was analyzed by comparing model simulation data with experimental data. The nonlinearities reflected in the spectra, namely, the excitations generated by paired laser pulses with a delay time, the logarithmic relationship between carrier density and surface photovoltage (SPV), and the effect of the change in tunneling barrier height depending on SPV, were examined along with the delay-time-dependent integration process used in measurement. The optimum conditions required to realize reliable measurement, as well as the validity of the microscopy technique, were demonstrated for the first time.

  12. Clinical study of confocal laser microscopy in fungal keratitis%应用激光共焦显微镜诊断真菌性角膜炎的临床研究

    Institute of Scientific and Technical Information of China (English)

    李昂; 范忠义

    2013-01-01

    目的:应用激光共焦显微镜观察真菌性角膜炎患者图像特点及菌丝和孢子检出率,探讨激光共焦显微镜检查在真菌性角膜炎临床诊断中的意义.方法:对41例41眼经门诊确诊为真菌性角膜炎的患者行角膜激光共焦显微镜检查,观察不同治疗期真菌性角膜炎患者活体角膜各层图像特点.结果:共焦显微镜下真菌性角膜炎患者图像有如下特点:(1)病变部位角膜各层形态结构破坏明显;角膜上皮至基质不同程度水肿;炎细胞浸润;神经结构破坏;基质层结构紊乱,透过度降低;(2)真菌菌丝是本病的特异性诊断依据,不同菌种感染在镜下菌丝有不同的影像学特点;(3)不同病变时期和治疗阶段,图像有很大差异,真菌菌丝的检出并不是诊断本病的唯一依据.结论:激光共焦显微镜检查具有无创、及时等优点,在临床诊断真菌性角膜炎中有重要参考意义,尤其是指导临床早期诊断、合理治疗及评价预后.%AIM: To examine the configuration of fungal keratitis and the detection rate of hypha and spore under confocal laser microscopy and investigate the value of confocal microscopy in the clinical diagnosis of fungal keratitis.METHODS: We conducted laserconfocal microscopy on 41 patients of 41 eyes diagnosed as fungal keratitis and compared the configuration of different layers of cornea in different stages.RESULTS: The fungal infected corneas histologically showed disordered layers, edema, infiltration of inflammatory cells, damaged sub-epithelial nerves and disordered stroma with reduced transparence. Hypha showed a specific base on the diagnosis of the disease, but not the only, it may appeared different configuration in different types of fungal keratitis and at different stages of the disease.CONCLUSION: Confocal laser microscopy is a noninvasive and rapid intuitive technique, and can offer helpful analysis in the early diagnosis, reasonable treatment and prognosis

  13. Ultra-sharp metal and nanotube-based probes for applications in scanning microscopy and neural recording.

    Science.gov (United States)

    Borzenets, I V; Yoon, I; Prior, M M; Donald, B R; Mooney, R D; Finkelstein, G

    2012-04-01

    This paper discusses several methods for manufacturing ultra-sharp probes, with applications geared toward, but not limited to, scanning microscopy (STM, AFM) and intra-cellular recordings of neural signals. We present recipes for making tungsten, platinum/iridium alloy, and nanotube fibril tips. Electrical isolation methods using Parylene-C or PMMA are described.

  14. Fractographic features of glass-ceramic and zirconia-based dental restorations fractured during clinical function.

    Science.gov (United States)

    Oilo, Marit; Hardang, Anne D; Ulsund, Amanda H; Gjerdet, Nils R

    2014-06-01

    Fractures during clinical function have been reported as the major concern associated with all-ceramic dental restorations. The aim of this study was to analyze the fracture features of glass-ceramic and zirconia-based restorations fractured during clinical use. Twenty-seven crowns and onlays were supplied by dentists and dental technicians with information about type of cement and time in function, if available. Fourteen lithium disilicate glass-ceramic restorations and 13 zirconia-based restorations were retrieved and analyzed. Fractographic features were examined using optical microscopy to determine crack initiation and crack propagation of the restorations. The material comprised fractured restorations from one canine, 10 incisors, four premolars, and 11 molars. One crown was not categorized because of difficulty in orientation of the fragments. The results revealed that all core and veneer fractures initiated in the cervical margin and usually from the approximal area close to the most coronally placed curvature of the margin. Three cases of occlusal chipping were found. The margin of dental all-ceramic single-tooth restorations was the area of fracture origin. The fracture features were similar for zirconia, glass-ceramic, and alumina single-tooth restorations. Design features seem to be of great importance for fracture initiation.

  15. Relevance of guideline-based ICD indications to clinical practice.

    Science.gov (United States)

    Al-Jefairi, Nora; Burri, Haran

    2014-01-01

    The implantable cardioverter-defibrillator (ICD) has established itself as life-saving therapy in patients at risk for sudden cardiac death. Remarkable technological advances have made ICDs easier and safer to implant, with improved therapeutic and diagnostic functions and reduced morbidity. Guidelines on ICD indications have been proposed by American and European scientific societies since a number of years, based upon trials and expert opinion. In the context of variable economic and political constraints, it is questionable whether these guidelines may be applied to all settings. This review discusses the guideline-based indications, critically examines their applicability to clinical practice, and discusses alternatives to ICD therapy.

  16. An electron microscopy based method for the detection and quantification of nanomaterial number concentration in environmentally relevant media

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, A. [School of Geography, Earth and Environmental Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Lead, J.R., E-mail: jlead@mailbox.sc.edu [School of Geography, Earth and Environmental Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia 29208, SC (United States); Baalousha, M., E-mail: mbaalous@mailbox.sc.edu [Center for Environmental Nanoscience and Risk, Department of Environmental Health Sciences, Arnold School of Public Health, University South Carolina, Columbia 29208, SC (United States)

    2015-12-15

    Improved detection and characterization of nanomaterials (NMs) in complex environmental media requires the development of novel sampling approaches to improve the detection limit to be close to environmentally realistic concentrations. Transmission electron microscopy (TEM) is an indispensable metrological tool in nanotechnology and environmental nanoscience due to its high spatial resolution and analytical capabilities when coupled to spectroscopic techniques. However, these capabilities are hampered by the conventional sample preparation methods, which suffer from low NM recovery. The current work presents a validated, fully quantitative sampling technique for TEM that overcomes conventional sample preparation shortcomings, and thus enables the use of TEM for measurement of particle number concentration and their detection in complex media at environmentally realistic concentrations. This sampling method is based on ultracentrifugation of NMs from suspension onto a poly-L-lysine (PLL) functionalized TEM grid, using active deposition (by ultracentrifugation) and retention (by PLL interactions with NM surface) of NMs on the substrate, enabling fully quantitative analysis. Similar analysis with AFM was satisfactory in simple media but the lack of chemical-selectivity of AFM limits its applicability for the detection of NMs in complex environmental samples. The sampling approach was validated using both citrate- and PVP-coated AuNMs in pure water, which demonstrated an even distribution of NM on the TEM grid and high NM recovery (80–100%) at environmentally relevant NM concentrations (ca. 0.20–100 μg L{sup −1}). The applicability of the sampling method to complex environmental samples was demonstrated by the quantification of particle number concentration of AuNMs in EPA soft water (with and without Suwannee River fulvic acid) and lake water. This sample preparation approach is also applicable to other types of NMs with some modifications (e.g. centrifugation

  17. Movement-Based Priming: Clinical Applications and Neural Mechanisms.

    Science.gov (United States)

    Stoykov, Mary Ellen; Corcos, Daniel Montie; Madhavan, Sangeetha

    2017-01-01

    Priming can be described as behavior change generated by preceding stimuli. Although various types of priming have been long studied in the field of psychology, priming that targets motor cortex is a relatively new topic of research in the fields of motor control and rehabilitation. In reference to a rehabilitation intervention, priming is categorized as a restorative approach. There are a myriad of possible priming approaches including noninvasive brain stimulation, motor imagery, and sensory-based priming, to name a few. The authors report on movement-based priming which, compared to other priming types, is less frequently examined and under reported. Movement-based priming includes, but is not limited to, bilateral motor priming, unilateral priming, and aerobic exercise. Clinical and neural mechanistic aspects of movement-based priming techniques are explored.

  18. Deterministic versus evidence-based attitude towards clinical diagnosis.

    Science.gov (United States)

    Soltani, Akbar; Moayyeri, Alireza

    2007-08-01

    Generally, two basic classes have been proposed for scientific explanation of events. Deductive reasoning emphasizes on reaching conclusions about a hypothesis based on verification of universal laws pertinent to that hypothesis, while inductive or probabilistic reasoning explains an event by calculation of some probabilities for that event to be related to a given hypothesis. Although both types of reasoning are used in clinical practice, evidence-based medicine stresses on the advantages of the second approach for most instances in medical decision making. While 'probabilistic or evidence-based' reasoning seems to involve more mathematical formulas at the first look, this attitude is more dynamic and less imprisoned by the rigidity of mathematics comparing with 'deterministic or mathematical attitude'. In the field of medical diagnosis, appreciation of uncertainty in clinical encounters and utilization of likelihood ratio as measure of accuracy seem to be the most important characteristics of evidence-based doctors. Other characteristics include use of series of tests for refining probability, changing diagnostic thresholds considering external evidences and nature of the disease, and attention to confidence intervals to estimate uncertainty of research-derived parameters.

  19. Clinical TVA-based studies: a general review

    Directory of Open Access Journals (Sweden)

    Thomas eHabekost

    2015-03-01

    Full Text Available In combination with whole report and partial report tasks, the Theory of Visual Attention (TVA can be used to estimate individual differences in five basic attentional parameters: The visual processing speed, the storage capacity of visual short-term memory, the perceptual threshold, the efficiency of top-down selectivity, and the spatial bias of attentional weighting. TVA-based assessment has been used in about 30 studies to investigate attentional deficits in a range of neurological and psychiatric conditions: (a neglect and simultanagnosia, (b reading disturbances, (c aging and neurodegenerative diseases, and most recently (d neurodevelopmental disorders. The article introduces TVA based assessment, discusses its methodology and psychometric properties, and reviews the progress made in each of the four research fields. The empirical results demonstrate the general usefulness of TVA-based assessment for many types of clinical neuropsychological research. The method’s most important qualities are cognitive specificity and theoretical grounding, but it is also characterized by good reliability and sensitivity to minor deficits. The review concludes by pointing to promising new areas for clinical TVA-based research.

  20. A JAVA-based multimedia tool for clinical practice guidelines.

    Science.gov (United States)

    Maojo, V; Herrero, C; Valenzuela, F; Crespo, J; Lazaro, P; Pazos, A

    1997-01-01

    We have developed a specific language for the representation of Clinical Practice Guidelines (CPGs) and Windows C++ and platform independent JAVA applications for multimedia presentation and edition of electronically stored CPGs. This approach facilitates translation of guidelines and protocols from paper to computer-based flowchart representations. Users can navigate through the algorithm with a friendly user interface and access related multimedia information within the context of each clinical problem. CPGs can be stored in a computer server and distributed over the World Wide Web, facilitating dissemination, local adaptation, and use as a reference element in medical care. We have chosen the Agency for Health Care and Policy Research's heart failure guideline to demonstrate the capabilities of our tool.

  1. Transmission Electron Microscopy of a CMSX-4 Ni-Base Superalloy Produced by Selective Electron Beam Melting

    Directory of Open Access Journals (Sweden)

    Alireza B. Parsa

    2016-10-01

    Full Text Available In this work, the microstructures of superalloy specimens produced using selective electron beam melting additive manufacturing were characterized. The materials were produced using a CMSX-4 powder. Two selective electron beam melting processing strategies, which result in higher and lower effective cooling rates, are described. Orientation imaging microscopy, scanning transmission electron microscopy and conventional high resolution transmission electron microscopy are used to investigate the microstructures. Our results suggest that selective electron beam melting processing results in near equilibrium microstructures, as far as γ′ volume fractions, the formation of small amounts of TCP phases and the partitioning behavior of the alloy elements are concerned. As expected, higher cooling rates result in smaller dendrite spacings, which are two orders of magnitude smaller than observed during conventional single crystal casting. During processing, columnar grains grow in <100> directions, which are rotated with respect to each other. There are coarse γ/γ′ microstructures in high angle boundary regions. Dislocation networks form low angle boundaries. A striking feature of the as processed selective electron beam melting specimens is their high dislocation density. From a fundamental point of view, this opens new possibilities for the investigation of elementary dislocation processes which accompany solidification.

  2. Fickian-Based Empirical Approach for Diffusivity Determination in Hollow Alginate-Based Microfibers Using 2D Fluorescence Microscopy and Comparison with Theoretical Predictions

    Directory of Open Access Journals (Sweden)

    Maryam Mobed-Miremadi

    2014-12-01

    Full Text Available Hollow alginate microfibers (od = 1.3 mm, id = 0.9 mm, th = 400 µm, L = 3.5 cm comprised of 2% (w/v medium molecular weight alginate cross-linked with 0.9 M CaCl2 were fabricated to model outward diffusion capture by 2D fluorescent microscopy. A two-fold comparison of diffusivity determination based on real-time diffusion of Fluorescein isothiocyanate molecular weight (FITC MW markers was conducted using a proposed Fickian-based approach in conjunction with a previously established numerical model developed based on spectrophotometric data. Computed empirical/numerical (Dempiricial/Dnumerical diffusivities characterized by small standard deviations for the 4-, 70- and 500-kDa markers expressed in m2/s are (1.06 × 10−9 ± 1.96 × 10−10/(2.03 × 10−11, (5.89 × 10−11 ± 2.83 × 10−12/(4.6 × 10−12 and (4.89 × 10−12 ± 3.94 × 10−13/(1.27 × 10−12, respectively, with the discrimination between the computation techniques narrowing down as a function of MW. The use of the numerical approach is recommended for fluorescence-based measurements as the standard computational method for effective diffusivity determination until capture rates (minimum 12 fps for the 4-kDa marker and the use of linear instead of polynomial interpolating functions to model temporal intensity gradients have been proven to minimize the extent of systematic errors associated with the proposed empirical method.

  3. Implementing security in computer based patient records clinical experiences.

    Science.gov (United States)

    Iversen, K R; Heimly, V; Lundgren, T I

    1995-01-01

    In Norway, organizational changes in hospitals and a stronger focus on patient safety have changed the way of organizing and managing paper based patient records. Hospital-wide patient records tend to replace department based records. Since not only clinicians, but also other non-medical staff have access to the paper records, they also have easy access to all the information which is available on a specific patient; such a system has obvious 'side effects' on privacy and security. Computer based patient records (CPRs) can provide the solution to this apparent paradox if the complex aspects of security, privacy, effectiveness, and user friendliness are focused on jointly from the outset in designing such systems. Clinical experiences in Norway show that it is possible to design patient record systems that provide a very useful tool for clinicians and other health care personnel (HCP) while fully complying with comprehensive security and privacy requirements.

  4. Photoelectron Microscopy

    Science.gov (United States)

    King, Paul Lawrence

    1992-01-01

    This thesis describes the theory and first operations of a novel synchrotron-based imaging system allowing photoemission spectroscopy (XPS or ESCA) to be performed at lateral resolutions better than 10 microns. Originally developed in David Turner's group at Oxford, the MicroESCA^ {rm TM} relies on the diverging magnetic field from a 7 Tesla superconducting solenoid to project photoemitted electrons from a sample to an imaging detector located 1.5 meters away. The diverging magnetic field converts off-axis momentum to forward momentum and electrons form a magnified image at the detector while moving nearly parallel to one another. Because of this "parallelization", a planar gridded retarding field analyzer achieves excellent energy resolution with only minor impact on image quality. The thesis begins with an overview of the various techniques by which high lateral resolution photoelectron spectroscopy can be achieved. This is followed by a theoretical treatment of magnetic projection leading to predictions of lateral and energy resolution. Chapter 3 documents resolution tests and known deviations from ideality. Image forming capabilities and energy resolution of the retarding field analyzer are demonstrated at near-theoretical limits. Practical limitations of the microscope are recognized in the form of poor signal to noise ratios of core level images which originate from a combination of the narrow dynamic range of the imaging detector and the large backgrounds inherent in retarding field spectroscopy of solids. Chapter 4 describes an interactive image processing and interpretation scheme that relies on scatter plots and principal component analysis to reduce the dimensionality of retarding field image sets and improve image signal to noise. This procedure is generally applicable to all imaging spectroscopies and an example from SEM-based energy dispersive spectroscopy (EDS) is included. In a final results section, variations in the surface Fermi levels on cleaved

  5. Activity-based costing for clinical paths. An example to improve clinical cost & efficiency.

    Science.gov (United States)

    Asadi, M J; Baltz, W A

    1996-01-01

    How much does this medical service or surgical procedure cost the hospital to provide? What is the most efficient clinical pathway that maximizes the quality of patient care while minimizing costs? More and more hospitals are discovering that they don't have solid answers to these critically important questions. In an age of managed care and capitation, however, it is imperative for management to know if the patient care services they provide are making or losing money-and by how much. This article discusses how a powerful new tool called activity-based costing (ABC) can be used to help hospitals accurately determine patient care costs. We show how to build a model that combines both clinical and financial data to measure how efficiently the operation allocates human, material and capital resources to provide its services. The modeling approach described in this article can be used to better analyze a wide range of important operational and financial issues, including: How to efficiently allocate resources, and what resources will be needed as patient demand changes-ideal for operational management and planning; How efficiently activities and processes are performed to meet patient needs-effective for measuring performance and improving quality; Determining clinical pathway profitability-essential for understanding where you're making or losing money; Cycle time, throughput and the impact of resource capacity constraints-critical for meeting patient demand; Costs of idle capacity-important for using resources more efficiently. We will illustrate with an example how this modeling technique can be used to develop and implement efficient clinical pathways.

  6. Ten practical, theory-based tips for clinical course planners

    DEFF Research Database (Denmark)

    Balslev, T.; Westphall, I.; Blichfeldt, S.

    2008-01-01

    A list of practical advice and examples are given based on the literature. E-learning with cliffhanger text-cases can activate prior knowledge, and selected examination skills can be trained with simulated patients. Patient video recordings can be used to train clinical reasoning skills, including...... pattern recognition and hypothetic-deductive approaches. Interactive approaches, for example, questioning, quizzes or buzz groups imply active involvement and participation. Quizzes and MCQ-testing can provide a formative 'check-up' on learning and point to gaps in understanding for the teachers...

  7. Do evidence-based guidelines change clinical practice patterns?

    DEFF Research Database (Denmark)

    Kessel, Line; Erngaard, Ditte; Flesner, Per;

    2017-01-01

    In 2013, the Danish Health and Medicines Authorities published a National Clinical Guideline on the treatment of age-related cataracts. The guideline provided evidence-based recommendations on the indication for cataract surgery, cataract surgery in patients with age-related macular degeneration...... sequential bilateral cataract surgery and on the postoperative check-up of patients. A questionnaire was sent to all members of the Danish Ophthalmological Society before and after publication of the guideline. The responses showed that the guideline had changed practice patterns so that surgeons were more...

  8. Clinical Holistic Medicine: Applied Consciousness-Based Medicine

    OpenAIRE

    Søren Ventegodt; Joav Merrick

    2004-01-01

    Consciousness-based medicine is our term for a form of medical treatment that works by direct appeal to the consciousness of the patient, in contrast to modern biomedical treatment where drugs are used to affect body chemistry. With this concept, maybe we are (in a sense) turning back to the “old medicine”, where the family physician was the all-concerned “old country doctor” who knew the child, the siblings, the parents, the family, and the village. In a series of papers on clinical holistic...

  9. Evidence-based review of clinical studies on pulpotomy.

    Science.gov (United States)

    2009-08-01

    Although pulpotomy procedures have a long history of clinical application, comparatively few dental clinical trials have evaluated this treatment approach. In this section, we provide an analysis of recent clinical studies evaluating pulpotomy procedures in dental patients.

  10. Fresnel zone-plate based X-ray microscopy in Zernike phase contrast with sub-50 nm resolution at NSRL

    Energy Technology Data Exchange (ETDEWEB)

    Chen Jie; Li Wenjie; Tian Jinping; Liu Longhua; Xiong Ying; Liu Gang; Wu Ziyu; Tian Yangchao [National Synchrotron Radiation Laboratory (China); Liu Yijin [School of Physics (China); Yue Zhengbo; Yu Hanqing [Laboratory of Environmental Engineering, School of Chemistry, University of Science and Technology of China, Hefei Anhui 230029 (China); Wang Chunru, E-mail: ychtian@ustc.edu.c [Institute of Chemistry, Chinese Academy of Sciences, Beijing 10060 (China)

    2009-09-01

    A transmission X-ray microscope using Fresnel zone-plates (FZPs) has been installed at U7A beamline of National Synchrotron Radiation Laboratory (NSRL). The objective FZP with 45 nm outermost zone width delivers a sub-50 nm resolution. A gold phase ring with 2.5 {mu}m thickness and 4 {mu}m width was placed at the focal plane of the objective FZP at 8 keV to produce a negative Zernike phase contrast. A series of samples were used to test the performance of the Zernike phase contrast X-ray microscopy.

  11. Characterization of Metal Oxide-Based Gas Nanosensors and Microsensors Fabricated via Local Anodic Oxidation Using Atomic Force Microscopy

    Directory of Open Access Journals (Sweden)

    Bráulio S. Archanjo

    2013-01-01

    Full Text Available This work reports on nanoscale and microscale metal oxide gas sensors, consisting of metal-semiconductor-metal barriers designed via scanning probe microscopy. Two distinct metal oxides, molybdenum and titanium oxides, were tested at different temperatures using CO2 and H2 as test gases. Sensitivities down to ppm levels are demonstrated, and the influence of dry and humid working atmospheres on these metal oxide conductivities was studied. Furthermore, the activation energy was evaluated and analyzed within working sensor temperature range. Finally, full morphological, chemical, and structural analyses of the oxides composites are provided allowing their identification as MoO3 and Ti.

  12. Investigation of (Fe,Co)NbB-Based Nanocrystalline Soft Magnetic Alloys by Lorentz Microscopy and Off-Axis Electron Holography.

    Science.gov (United States)

    Zheng, Changlin; Kirmse, Holm; Long, Jianguo; Laughlin, David E; McHenry, Michael E; Neumann, Wolfgang

    2015-04-01

    The relationship between microstructure and magnetic properties of a (Fe,Co)NbB-based nanocrystalline soft magnetic alloy was investigated by analytical transmission electron microscopy (TEM). The microstructures of (Fe0.5Co0.5)80Nb4B13Ge2Cu1 nanocrystalline alloys annealed at different temperatures were characterized by TEM and electron diffraction. The magnetic structures were analyzed by Lorentz microscopy and off-axis electron holography, including quantitative measurement of domain wall width, induction, and in situ magnetic domain imaging. The results indicate that the magnetic domain structure and particularly the dynamical magnetization behavior of the alloys strongly depend on the microstructure of the nanocrystalline alloys. Smaller grain size and random orientation of the fine particles decrease the magneto-crystalline anisotropy and suggests better soft magnetic properties which may be explained by the anisotropy model of Herzer.

  13. Use of colloidal quantum dots as a digitally switched swept light source for gold nanoparticle based hyperspectral microscopy

    Science.gov (United States)

    Hoshino, Kazunori; Joshi, Pratixa. P.; Bhave, Gauri.; Sokolov, Konstantin V.; Zhang, Xiaojing

    2014-01-01

    We propose a method to utilize colloidal quantum dots (QDs) as a swept light source for hyperspectral microscopy. The use of QD allows for uniform multicolor emission which covers visible-NIR wavelengths. We used 8 colors of CdSe/ZnS and CdTe/ZnS colloidal quantum dots with the peak emission wavelengths from 520 nm to 800 nm. The QDs are packed in a compact enclosure, composing a low-cost, solid-state swept light source that can be easily used in most microscopes. Multicolor emission from the QDs is simply controlled by digitally switching excitation UVLEDs, eliminating the use of mechanically-driven gratings or filters. We used gold nanoparticles as optical markers for hyperspectral microscopy. Due to the effect of localized surface plasmon resonance, gold nanoparticles demonstrate size and shape-dependent absorption spectra. Employed in a standard microscope, the QD light source enabled multispectral absorption imaging of macrophage cells labeled with gold nanorods and nanospheres. PMID:24877018

  14. Signal-Characteristic analysis with respect to backing material of PVDF-based high-frequency ultrasound for photoacoustic microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jun Su; Chang, Jin Ho [Dept. of Electronic Engineering, Sogang University, Seoul (Korea, Republic of)

    2015-04-15

    Photoacoustic microscopy is capable of providing high-resolution molecular images, and its spatial resolution is typically determined by ultrasonic transducers used to receive the photoacoustic signals. Therefore, ultrasonic transducers for photoacoustic microscopy (PAM) should have a high operating frequency, broad bandwidth, and high signal-reception efficiency. Polyvinylidene fluoride (PVDF) is a suitable material. To take full advantage of this material, the selection of the backing material is crucial, as it influences the center frequency and bandwidth of the transducer. Therefore, we experimentally determined the most suitable backing material among EPO-TEK 301, E-Solder 3022, and RTV. For this, three PVDF high-frequency single-element transducers were fabricated with each backing material. The center frequency and -6 dB bandwidth of each transducer were ascertained by a pulse-echo test. The spatial resolution of each transducer was examined using wire-target images. The experimental results indicated that EPO-TEK 301 is the most suitable backing material for a PAM transducer. This material provides the highest signal magnitude and a reasonable bandwidth because a large portion of the energy propagates toward the front medium, and the PVDF resonates in the half-wave mode.

  15. Formulation factors affecting the isomerization rate of betamethasone-17-valerate in a developmental hydrophilic cream - a HPLC and microscopy based stability study.

    Science.gov (United States)

    Byrne, Jonathan; Wyraz, Anke; Velasco-Torrijos, Trinidad; Reinhardt, Robert

    2016-02-19

    The formulation of betamethasone-17-valerate (BV) into topical medicines presents a significant challenge for the formulation chemist. The substance is susceptible to acid and base catalyzed isomerization in aqueous environments, which results in valerate transesterification from carbon 17 to carbon 21 of the steroid ring system. This acyl migration process is of significant clinical importance since the 21-valerate ester possesses only a fraction of the potency of the 17-valerate parent compound. Isomerization of BV should therefore be reduced to a minimum through design of a suitable drug vehicle. In this study, the effect of varying the concentration of several excipient components on the isomerization rate of betamethasone valerate in a model hydrophilic cream has been investigated. These excipients include the emulsifier macrogolstearylether-20/21, the co-emulsifier cetylstearyl alcohol and the thickening agent hydroxyl propyl methylcellulose. Additionally, the influence of pH, the presence of the antioxidant, alpha-tocopherol, as well as the chelating agent, disodium edetate, on the stability of the formulation have been investigated. Trial drug product formulations, which were designed to investigate the influence of the above-mentioned components/parameters were manufactured and their stability was tested according to current ICH Guidelines. The content, purity and crystalline structure of the active substance in these formulations was analyzed by a combination of HPLC and microscopy techniques. The study demonstrates that the rate of isomerization of betamethasone valerate depends significantly on the concentration of emulsifier used in the cream formulation. At higher concentrations of emulsifier the isomerization proceeds rapidly with significant degradation over a period of weeks, whereas at lower concentrations significant degradation may not be observed, even after several years' storage. The influence of the emulsifier has been shown to be

  16. Clinical trial designs for testing biomarker-based personalized therapies

    Science.gov (United States)

    Lai, Tze Leung; Lavori, Philip W; Shih, Mei-Chiung I; Sikic, Branimir I

    2014-01-01

    Background Advances in molecular therapeutics in the past decade have opened up new possibilities for treating cancer patients with personalized therapies, using biomarkers to determine which treatments are most likely to benefit them, but there are difficulties and unresolved issues in the development and validation of biomarker-based personalized therapies. We develop a new clinical trial design to address some of these issues. The goal is to capture the strengths of the frequentist and Bayesian approaches to address this problem in the recent literature and to circumvent their limitations. Methods We use generalized likelihood ratio tests of the intersection null and enriched strategy null hypotheses to derive a novel clinical trial design for the problem of advancing promising biomarker-guided strategies toward eventual validation. We also investigate the usefulness of adaptive randomization (AR) and futility stopping proposed in the recent literature. Results Simulation studies demonstrate the advantages of testing both the narrowly focused enriched strategy null hypothesis related to validating a proposed strategy and the intersection null hypothesis that can accommodate to a potentially successful strategy. AR and early termination of ineffective treatments offer increased probability of receiving the preferred treatment and better response rates for patients in the trial, at the expense of more complicated inference under small-to-moderate total sample sizes and some reduction in power. Limitations The binary response used in the development phase may not be a reliable indicator of treatment benefit on long-term clinical outcomes. In the proposed design, the biomarker-guided strategy (BGS) is not compared to ‘standard of care’, such as physician’s choice that may be informed by patient characteristics. Therefore, a positive result does not imply superiority of the BGS to ‘standard of care’. The proposed design and tests are valid asymptotically

  17. Preparing dental students for careers as independent dental professionals: clinical audit and community-based clinical teaching.

    Science.gov (United States)

    Lynch, C D; Llewelyn, J; Ash, P J; Chadwick, B L

    2011-05-28

    Community-based clinical teaching programmes are now an established feature of most UK dental school training programmes. Appropriately implemented, they enhance the educational achievements and competences achieved by dental students within the earlier part of their developing careers, while helping students to traverse the often-difficult transition between dental school and vocational/foundation training and independent practice. Dental school programmes have often been criticised for 'lagging behind' developments in general dental practice - an important example being the so-called 'business of dentistry', including clinical audit. As readers will be aware, clinical audit is an essential component of UK dental practice, with the aims of improving the quality of clinical care and optimising patient safety. The aim of this paper is to highlight how training in clinical audit has been successfully embedded in the community-based clinical teaching programme at Cardiff.

  18. Design and construction of a cost-efficient Arduino-based mirror galvanometer system for scanning optical microscopy

    Science.gov (United States)

    Hsu, Jen-Feng; Dhingra, Shonali; D'Urso, Brian

    2017-01-01

    Mirror galvanometer systems (galvos) are commonly employed in research and commercial applications in areas involving laser imaging, laser machining, laser-light shows, and others. Here, we present a robust, moderate-speed, and cost-efficient home-built galvo system. The mechanical part of this design consists of one mirror, which is tilted around two axes with multiple surface transducers. We demonstrate the ability of this galvo by scanning the mirror using a computer, via a custom driver circuit. The performance of the galvo, including scan range, noise, linearity, and scan speed, is characterized. As an application, we show that this galvo system can be used in a confocal scanning microscopy system.

  19. Finite-difference time-domain-based optical microscopy simulation of dispersive media facilitates the development of optical imaging techniques

    Science.gov (United States)

    Zhang, Di; Capoglu, Ilker; Li, Yue; Cherkezyan, Lusik; Chandler, John; Spicer, Graham; Subramanian, Hariharan; Taflove, Allen; Backman, Vadim

    2016-06-01

    Combining finite-difference time-domain (FDTD) methods and modeling of optical microscopy modalities, we previously developed an open-source software package called Angora, which is essentially a "microscope in a computer." However, the samples being simulated were limited to nondispersive media. Since media dispersions are common in biological samples (such as cells with staining and metallic biomarkers), we have further developed a module in Angora to simulate samples having complicated dispersion properties, thereby allowing the synthesis of microscope images of most biological samples. We first describe a method to integrate media dispersion into FDTD, and we validate the corresponding Angora dispersion module by applying Mie theory, as well as by experimentally imaging gold microspheres. Then, we demonstrate how Angora can facilitate the development of optical imaging techniques with a case study.

  20. Multiscale phase mapping of LiFePO4-based electrodes by transmission electron microscopy and electron forward scattering diffraction.

    Science.gov (United States)

    Robert, Donatien; Douillard, Thierry; Boulineau, Adrien; Brunetti, Guillaume; Nowakowski, Pawel; Venet, Denis; Bayle-Guillemaud, Pascale; Cayron, Cyril

    2013-12-23

    LiFePO4 and FePO4 phase distributions of entire cross-sectioned electrodes with various Li content are investigated from nanoscale to mesoscale, by transmission electron microscopy and by the new electron forward scattering diffraction technique. The distributions of the fully delithiated (FePO4) or lithiated particles (LiFePO4) are mapped on large fields of view (>100 × 100 μm(2)). Heterogeneities in thin and thick electrodes are highlighted at different scales. At the nanoscale, the statistical analysis of 64 000 particles unambiguously shows that the small particles delithiate first. At the mesoscale, the phase maps reveal a core-shell mechanism at the scale of the agglomerates with a preferential pathway along the electrode porosities. At larger scale, lithiation occurs in thick electrodes "stratum by stratum" from the surface in contact with electrolyte toward the current collector.

  1. Miniaturized video-microscopy system for near real-time water quality biomonitoring using microfluidic chip-based devices

    Science.gov (United States)

    Huang, Yushi; Nigam, Abhimanyu; Campana, Olivia; Nugegoda, Dayanthi; Wlodkowic, Donald

    2016-12-01

    Biomonitoring studies apply biological responses of sensitive biomonitor organisms to rapidly detect adverse environmental changes such as presence of physic-chemical stressors and toxins. Behavioral responses such as changes in swimming patterns of small aquatic invertebrates are emerging as sensitive endpoints to monitor aquatic pollution. Although behavioral responses do not deliver information on an exact type or the intensity of toxicants present in water samples, they could provide orders of magnitude higher sensitivity than lethal endpoints such as mortality. Despite the advantages of behavioral biotests performed on sentinel organisms, their wider application in real-time and near realtime biomonitoring of water quality is limited by the lack of dedicated and automated video-microscopy systems. Current behavioral analysis systems rely mostly on static test conditions and manual procedures that are time-consuming and labor intensive. Tracking and precise quantification of locomotory activities of multiple small aquatic organisms requires high-resolution optical data recording. This is often problematic due to small size of fast moving animals and limitations of culture vessels that are not specially designed for video data recording. In this work, we capitalized on recent advances in miniaturized CMOS cameras, high resolution optics and biomicrofluidic technologies to develop near real-time water quality sensing using locomotory activities of small marine invertebrates. We present proof-of-concept integration of high-resolution time-resolved video recording system and high-throughput miniaturized perfusion biomicrofluidic platform for optical tracking of nauplii of marine crustacean Artemia franciscana. Preliminary data demonstrate that Artemia sp. exhibits rapid alterations of swimming patterns in response to toxicant exposure. The combination of video-microscopy and biomicrofluidic platform facilitated straightforward recording of fast moving objects. We

  2. Quantitative Analysis of Rat Dorsal Root Ganglion Neurons Cultured on Microelectrode Arrays Based on Fluorescence Microscopy Image Processing.

    Science.gov (United States)

    Mari, João Fernando; Saito, José Hiroki; Neves, Amanda Ferreira; Lotufo, Celina Monteiro da Cruz; Destro-Filho, João-Batista; Nicoletti, Maria do Carmo

    2015-12-01

    Microelectrode Arrays (MEA) are devices for long term electrophysiological recording of extracellular spontaneous or evocated activities on in vitro neuron culture. This work proposes and develops a framework for quantitative and morphological analysis of neuron cultures on MEAs, by processing their corresponding images, acquired by fluorescence microscopy. The neurons are segmented from the fluorescence channel images using a combination of segmentation by thresholding, watershed transform, and object classification. The positioning of microelectrodes is obtained from the transmitted light channel images using the circular Hough transform. The proposed method was applied to images of dissociated culture of rat dorsal root ganglion (DRG) neuronal cells. The morphological and topological quantitative analysis carried out produced information regarding the state of culture, such as population count, neuron-to-neuron and neuron-to-microelectrode distances, soma morphologies, neuron sizes, neuron and microelectrode spatial distributions. Most of the analysis of microscopy images taken from neuronal cultures on MEA only consider simple qualitative analysis. Also, the proposed framework aims to standardize the image processing and to compute quantitative useful measures for integrated image-signal studies and further computational simulations. As results show, the implemented microelectrode identification method is robust and so are the implemented neuron segmentation and classification one (with a correct segmentation rate up to 84%). The quantitative information retrieved by the method is highly relevant to assist the integrated signal-image study of recorded electrophysiological signals as well as the physical aspects of the neuron culture on MEA. Although the experiments deal with DRG cell images, cortical and hippocampal cell images could also be processed with small adjustments in the image processing parameter estimation.

  3. Model Comparison for Breast Cancer Prognosis Based on Clinical Data.

    Directory of Open Access Journals (Sweden)

    Sabri Boughorbel

    Full Text Available We compared the performance of several prediction techniques for breast cancer prognosis, based on AU-ROC performance (Area Under ROC for different prognosis periods. The analyzed dataset contained 1,981 patients and from an initial 25 variables, the 11 most common clinical predictors were retained. We compared eight models from a wide spectrum of predictive models, namely; Generalized Linear Model (GLM, GLM-Net, Partial Least Square (PLS, Support Vector Machines (SVM, Random Forests (RF, Neural Networks, k-Nearest Neighbors (k-NN and Boosted Trees. In order to compare these models, paired t-test was applied on the model performance differences obtained from data resampling. Random Forests, Boosted Trees, Partial Least Square and GLMNet have superior overall performance, however they are only slightly higher than the other models. The comparative analysis also allowed us to define a relative variable importance as the average of variable importance from the different models. Two sets of variables are identified from this analysis. The first includes number of positive lymph nodes, tumor size, cancer grade and estrogen receptor, all has an important influence on model predictability. The second set incudes variables related to histological parameters and treatment types. The short term vs long term contribution of the clinical variables are also analyzed from the comparative models. From the various cancer treatment plans, the combination of Chemo/Radio therapy leads to the largest impact on cancer prognosis.

  4. Nanomaterial-Based Electrochemical Immunosensors for Clinically Significant Biomarkers

    Directory of Open Access Journals (Sweden)

    Niina J. Ronkainen

    2014-06-01

    Full Text Available Nanotechnology has played a crucial role in the development of biosensors over the past decade. The development, testing, optimization, and validation of new biosensors has become a highly interdisciplinary effort involving experts in chemistry, biology, physics, engineering, and medicine. The sensitivity, the specificity and the reproducibility of biosensors have improved tremendously as a result of incorporating nanomaterials in their design. In general, nanomaterials-based electrochemical immunosensors amplify the sensitivity by facilitating greater loading of the larger sensing surface with biorecognition molecules as well as improving the electrochemical properties of the transducer. The most common types of nanomaterials and their properties will be described. In addition, the utilization of nanomaterials in immunosensors for biomarker detection will be discussed since these biosensors have enormous potential for a myriad of clinical uses. Electrochemical immunosensors provide a specific and simple analytical alternative as evidenced by their brief analysis times, inexpensive instrumentation, lower assay cost as well as good portability and amenability to miniaturization. The role nanomaterials play in biosensors, their ability to improve detection capabilities in low concentration analytes yielding clinically useful data and their impact on other biosensor performance properties will be discussed. Finally, the most common types of electroanalytical detection methods will be briefly touched upon.

  5. Framework for clinical data standardization based on archetypes.

    Science.gov (United States)

    Maldonado, Jose A; Moner, David; Tomás, Diego; Angulo, Carlos; Robles, Montserrat; Fernández, Jesualdo T

    2007-01-01

    Standardization of data is a prerequisite to achieve semantic interoperability in any domain. This is even more important in the healthcare sector where the need for exchanging health related data among professional and institutions is not an exception but the rule. Currently, there are several international organizations working on the definition of electronic health record architectures, some of them based on a dual-model approach. We present both an archetype modeling framework and LinkEHR-ED, an archetype editor and mapping tool for transforming existing electronic healthcare data which do not conform to a particular electronic healthcare record architecture into compliant electronic health records extracts. In particular, archetypes in LinkEHR-ED are formal representations of clinical concepts built on a particular reference model but enriched with mapping information to data sources which define how to extract and transform existing data in order to generate standardized XML documents.

  6. A GPU-based computer-assisted microscopy system for assessing the importance of different families of histological characteristics in cancer diagnosis

    Science.gov (United States)

    Glotsos, Dimitris; Kostopoulos, Spiros; Sidiropoulos, Konstantinos; Ravazoula, Panagiota; Kalatzis, Ioannis; Asvestas, Pantelis; Cavouras, Dionisis

    2014-01-01

    In this study a Computer-Aided Microscopy (CAM) system is proposed for investigating the importance of the histological criteria involved in diagnosing of cancers in microscopy in order to suggest the more informative features for discriminating low from high-grade brain tumours. Four families of criteria have been examined, involving the greylevel variations (i.e. texture), the morphology (i.e. roundness), the architecture (i.e. cellularity) and the overall tumour qualities (expert's ordinal scale). The proposed CAM system was constructed using a modified Seeded Region Growing algorithm for image segmentation, and the Probabilistic Neural Network classifier for image classification. The implementation was designed on a commercial Graphics Processing Unit card using parallel programming. The system's performance using textural, morphological, architectural and ordinal information was 90.8%, 87.0%, 81.2% and 88.9% respectively. Results indicate that nuclei texture is the most important family of features regarding the degree of malignancy, and, thus, may guide more accurate predictions for discriminating low from high grade gliomas. Considering that nuclei texture is almost impractical to be encoded by visual observation, the need to incorporate computer-aided diagnostic tools as second opinion in daily clinical practice of diagnosing rare brain tumours may be justified.

  7. Scanning near-field microscopy of microdisk resonator with InP/GalnP quantum dots using cantilever-based probes

    Science.gov (United States)

    Shelaev, A. V.; Mintairov, A. M.; Dorozhkin, P. S.; Bykov, V. A.

    2016-08-01

    We present cantilever-probe based scanning near-field microscopy (SNOM) studies of GaInP microdisks resonators (radii R=2 um and quality factors Q∼1000) with embedded InP quantum dots (QDs) emitting at ∼750 nm. Near-field photoluminescence spectroscopy in collection regime, using side excitation from micro-objective, was used for imaging of whispering-gallery modes (WGMs) with a spatial resolution below the light diffraction limit. Using collection-illumination regime we imaged the position of single InP/GaInP QDs in microdisk.

  8. The use of atomic force microscopy as an important technique to analyze the dispersion of nanometric fillers and morphology in nanocomposites and polymer blends based on elastomers

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Fabiula Danielli Bastos de; Scuracchio, Carlos Henrique, E-mail: fabiuladesousa@gmail.com [Universidade Federal do ABC (CECS/UFABC), Santo Andre, SP (Brazil). Centro de Engenharia, Modelagem e Ciencias Sociais Aplicadas

    2014-11-15

    AFM has been recognized as one of the most powerful tools for the analysis of surface morphologies because it creates three-dimensional images at angstrom and nano scale. This technique has been exhaustively used in the analyses of dispersion of nanometric components in nanocomposites and in polymer blends, because of the easiness of sample preparation and lower equipment maintenance costs compared to electron microscopy. In this review, contributions using AFM are described, with emphasis on the dispersion of nanofillers in polymeric matrices. It is aimed to show the importance of technical analysis for nanocomposites and polymer blends based on elastomers. (author)

  9. Electrochemical force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kalinin, Sergei V.; Jesse, Stephen; Collins, Liam F.; Rodriguez, Brian J.

    2017-01-10

    A system and method for electrochemical force microscopy are provided. The system and method are based on a multidimensional detection scheme that is sensitive to forces experienced by a biased electrode in a solution. The multidimensional approach allows separation of fast processes, such as double layer charging, and charge relaxation, and slow processes, such as diffusion and faradaic reactions, as well as capturing the bias dependence of the response. The time-resolved and bias measurements can also allow probing both linear (small bias range) and non-linear (large bias range) electrochemical regimes and potentially the de-convolution of charge dynamics and diffusion processes from steric effects and electrochemical reactivity.

  10. Correlated Light Microscopy and Electron Microscopy

    NARCIS (Netherlands)

    Sjollema, Klaas A.; Schnell, Ulrike; Kuipers, Jeroen; Kalicharan, Ruby; Giepmans, Ben N. G.; MullerReichert, T; Verkade, P

    2012-01-01

    Understanding where, when, and how biomolecules (inter)act is crucial to uncover fundamental mechanisms in cell biology. Recent developments in fluorescence light microscopy (FLM) allow protein imaging in living cells and at the near molecular level. However, fluorescence microscopy only reveals sel

  11. Clinical Holistic Medicine: Applied Consciousness-Based Medicine

    Directory of Open Access Journals (Sweden)

    Søren Ventegodt

    2004-01-01

    Full Text Available Consciousness-based medicine is our term for a form of medical treatment that works by direct appeal to the consciousness of the patient, in contrast to modern biomedical treatment where drugs are used to affect body chemistry. With this concept, maybe we are (in a sense turning back to the “old medicine”, where the family physician was the all-concerned “old country doctor” who knew the child, the siblings, the parents, the family, and the village. In a series of papers on clinical holistic medicine, we would like to present the classic art of healing, where the physician works mostly with his hands, then show how the modern biomedical physician performs with biochemistry, and finally introduce consciousness-based medicine. Some of our questions will be: If you improve your quality of life, will you also improve your health? Will learning more about yourself bring more purpose in your life? Will finding someone to live with in a loving and mutually respectful relationship improve your health? Scientists and thinkers like Antonovsky, Frankl, Maslow, and Jung have pointed to love as a unique way to coherence in life, and thus to biological order and a better health. Several scientific studies have also suggested that patients who focus on improving their quality of life usually will not follow the general statistics for survival, since somehow other factors are at play, which sometimes you will find referred to as “exceptional”.

  12. Clinical holistic medicine: applied consciousness-based medicine.

    Science.gov (United States)

    Ventegodt, Søren; Merrick, Joav

    2004-03-03

    Consciousness-based medicine is our term for a form of medical treatment that works by direct appeal to the consciousness of the patient, in contrast to modern biomedical treatment where drugs are used to affect body chemistry. With this concept, maybe we are (in a sense) turning back to the "old medicine", where the family physician was the all-concerned "old country doctor" who knew the child, the siblings, the parents, the family, and the village. In a series of papers on clinical holistic medicine, we would like to present the classic art of healing, where the physician works mostly with his hands, then show how the modern biomedical physician performs with biochemistry, and finally introduce consciousness-based medicine. Some of our questions will be: If you improve your quality of life, will you also improve your health? Will learning more about yourself bring more purpose in your life? Will finding someone to live with in a loving and mutually respectful relationship improve your health? Scientists and thinkers like Antonovsky, Frankl, Maslow, and Jung have pointed to love as a unique way to coherence in life, and thus to biological order and a better health. Several scientific studies have also suggested that patients who focus on improving their quality of life usually will not follow the general statistics for survival, since somehow other factors are at play, which sometimes you will find referred to as "exceptional".

  13. Wavelet-based decomposition of high resolution surface plasmon microscopy V(Z) curves at visible and near infrared wavelengths.

    Science.gov (United States)

    Boyer-Provera, E; Rossi, A; Oriol, L; Dumontet, C; Plesa, A; Berguiga, L; Elezgaray, J; Arneodo, A; Argoul, F

    2013-03-25

    Surface plasmon resonance is conventionally conducted in the visible range and, during the past decades, it has proved its efficiency in probing molecular scale interactions. Here we elaborate on the first implementation of a high resolution surface plasmon microscope that operates at near infrared (IR) wavelength for the specific purpose of living matter imaging. We analyze the characteristic angular and spatial frequencies of plasmon resonance in visible and near IR lights and how these combined quantities contribute to the V(Z) response of a scanning surface plasmon microscope (SSPM). Using a space-frequency wavelet decomposition, we show that the V(Z) response of the SSPM for red (632.8 nm) and near IR (1550 nm) lights includes the frequential response of plasmon resonance together with additional parasitic frequencies induced by the objective pupil. Because the objective lens pupil profile is often unknown, this space-frequency decomposition turns out to be very useful to decipher the characteristic frequencies of the experimental V(Z) curves. Comparing the visible and near IR light responses of the SSPM, we show that our objective lens, primarily designed for visible light microscopy, is still operating very efficiently in near IR light. Actually, despite their loss in resolution, the SSPM images obtained with near IR light remain contrasted for a wider range of defocus values from negative to positive Z values. We illustrate our theoretical modeling with a preliminary experimental application to blood cell imaging.

  14. Static Recrystallization Kinetics and Crystallographic Texture of Nb-Stabilized Ferritic Stainless Steel Based on Orientation Imaging Microscopy

    Science.gov (United States)

    Malta, Paula Oliveira; Alves, Davi Silva; Ferreira, Aline Oliveira Vasconcelos; Moutinho, Iane Dutra; Dias, Carolina Arriel Pedroso; Santos, Dagoberto Brandão

    2017-01-01

    In the present study, Nb-stabilized ferritic stainless steel was prepared with annealing (430-A) and without annealing (430-NA) annealing, and the microstructure of the resulting samples was examined. The steel was then subjected to cold rolling and isothermal annealing in order to analyze its recrystallization kinetics and texture evolution. Microstructural characterization was performed by scanning and transmission electron microscopies. Recrystallization kinetics were evaluated by measuring the microhardness of the samples, and analyzing their kernel average misorientation and grain orientation spread via electron backscatter diffraction. The Avrami exponent data revealed that one-dimensional grain growth occurred owing to the migration of high-angle grain boundaries. The mean activation energies for recrystallization for 430-NA and 430-A was found to be 365 and 419 kJ mol-1, respectively. The recrystallization texture was influenced by oriented nucleation and selected growth mechanisms, as well as by the Nb carbonitride distribution and grain boundary energy. The recrystallized and growing grains with the {554} orientation showed a dimensional advantage over the other recrystallized components. The coincident site lattice boundaries were attributed to the progression of recrystallization since the CSL numeric fraction increased as the temperature increased. The {554} component was associated with the ∑19a boundary, which exerted a significant control on the selective growth during the recrystallization.

  15. Static Recrystallization Kinetics and Crystallographic Texture of Nb-Stabilized Ferritic Stainless Steel Based on Orientation Imaging Microscopy

    Science.gov (United States)

    Malta, Paula Oliveira; Alves, Davi Silva; Ferreira, Aline Oliveira Vasconcelos; Moutinho, Iane Dutra; Dias, Carolina Arriel Pedroso; Santos, Dagoberto Brandão

    2017-03-01

    In the present study, Nb-stabilized ferritic stainless steel was prepared with annealing (430-A) and without annealing (430-NA) annealing, and the microstructure of the resulting samples was examined. The steel was then subjected to cold rolling and isothermal annealing in order to analyze its recrystallization kinetics and texture evolution. Microstructural characterization was performed by scanning and transmission electron microscopies. Recrystallization kinetics were evaluated by measuring the microhardness of the samples, and analyzing their kernel average misorientation and grain orientation spread via electron backscatter diffraction. The Avrami exponent data revealed that one-dimensional grain growth occurred owing to the migration of high-angle grain boundaries. The mean activation energies for recrystallization for 430-NA and 430-A was found to be 365 and 419 kJ mol-1, respectively. The recrystallization texture was influenced by oriented nucleation and selected growth mechanisms, as well as by the Nb carbonitride distribution and grain boundary energy. The recrystallized and growing grains with the {554} orientation showed a dimensional advantage over the other recrystallized components. The coincident site lattice boundaries were attributed to the progression of recrystallization since the CSL numeric fraction increased as the temperature increased. The {554} component was associated with the ∑19a boundary, which exerted a significant control on the selective growth during the recrystallization.

  16. Synchrotron-based in situ soft X-ray microscopy of Ag corrosion in aqueous chloride solution

    Science.gov (United States)

    Bozzini, B.; D'Urzo, L.; Gianoncelli, A.; Kaulich, B.; Kiskinova, M.; Prasciolu, M.; Tadjeddine, A.

    2009-09-01

    In this paper we report an in situ X-ray microscopy study of a model metal electrochemistry system, incorporating faradaic reactivity: the anodic corrosion and cathodic electrodeposition of Ag in aqueous systems. The information at sub-μm scale about morpho-chemical evolution of the electrified interface, provided by this novel electroanalytical approach fosters fundamental understanding of important issues concerning material fabrication and stability, which are crucial in developing the next generation electrochemical technologies, such as fuel cells and biosensors. The key methodology challenge faced in this pilot electrochemical experiments is combining a three-electrode configuration and wet environment, which required metal electrodes suitable for transmitting soft X-rays and a sealed cell allowing working in high vacuum. This has been solved via lithographic fabrication route fabricating 75 nm thick Ag electrodes and using Si3N4 membranes as X-ray windows and electrode support. Imaging in the STXM mode with phase contrast allowed us to monitor the corrosion morphologies and metal outgrowth features. Localised thickness variation and the build-up of reaction products of electron density different from that of the starting material have been detected with high sensitivity.

  17. Synchrotron-based in situ soft X-ray microscopy of Ag corrosion in aqueous chloride solution

    Energy Technology Data Exchange (ETDEWEB)

    Bozzini, B; D' Urzo, L [Dipartimento di Ingegneria dell' Innovazione, Universita del Salento, via Monteroni, 73100 Lecce (Italy); Gianoncelli, A; Kaulich, B; Kiskinova, M [Sincrotrone Trieste S.C.p.A., ELETTRA, s.s. 14 km 163.5 in Area Science Park, 34012 Basovizza, Trieste (Italy); Prasciolu, M [CNR-INFM TASC National Laboratory S.S.14 Km 163.5, Area Science Park, 34012 Basovizza, Trieste (Italy); Tadjeddine, A, E-mail: alessandra.gianoncelli@elettra.trieste.i [3UDIL/CNRS, BP34 91898 Orsay Cedex (France)

    2009-09-01

    In this paper we report an in situ X-ray microscopy study of a model metal electrochemistry system, incorporating faradaic reactivity: the anodic corrosion and cathodic electrodeposition of Ag in aqueous systems. The information at sub-{mu}m scale about morpho-chemical evolution of the electrified interface, provided by this novel electroanalytical approach fosters fundamental understanding of important issues concerning material fabrication and stability, which are crucial in developing the next generation electrochemical technologies, such as fuel cells and biosensors. The key methodology challenge faced in this pilot electrochemical experiments is combining a three-electrode configuration and wet environment, which required metal electrodes suitable for transmitting soft X-rays and a sealed cell allowing working in high vacuum. This has been solved via lithographic fabrication route fabricating 75 nm thick Ag electrodes and using Si{sub 3}N{sub 4} membranes as X-ray windows and electrode support. Imaging in the STXM mode with phase contrast allowed us to monitor the corrosion morphologies and metal outgrowth features. Localised thickness variation and the build-up of reaction products of electron density different from that of the starting material have been detected with high sensitivity.

  18. A custom image-based analysis tool for quantifying elastin and collagen micro-architecture in the wall of the human aorta from multi-photon microscopy.

    Science.gov (United States)

    Koch, Ryan G; Tsamis, Alkiviadis; D'Amore, Antonio; Wagner, William R; Watkins, Simon C; Gleason, Thomas G; Vorp, David A

    2014-03-21

    The aorta possesses a micro-architecture that imparts and supports a high degree of compliance and mechanical strength. Alteration of the quantity and/or arrangement of the main load-bearing components of this micro-architecture--the elastin and collagen fibers--leads to mechanical, and hence functional, changes associated with aortic disease and aging. Therefore, in the future, the ability to rigorously characterize the wall fiber micro-architecture could provide insight into the complicated mechanisms of aortic wall remodeling in aging and disease. Elastin and collagen fibers can be observed using state-of-the-art multi-photon microscopy. Image-analysis algorithms have been effective at characterizing fibrous constructs using various microscopy modalities. The objective of this study was to develop a custom MATLAB-language automated image-based analysis tool to describe multiple parameters of elastin and collagen micro-architecture in human soft fibrous tissue samples using multi-photon microscopy images. Human aortic tissue samples were used to develop the code. The tool smooths, cleans and equalizes fiber intensities in the image before segmenting the fibers into a binary image. The binary image is cleaned and thinned to a fiber skeleton representation of the image. The developed software analyzes the fiber skeleton to obtain intersections, fiber orientation, concentration, porosity, diameter distribution, segment length and tortuosity. In the future, the developed custom image-based analysis tool can be used to describe the micro-architecture of aortic wall samples in a variety of conditions. While this work targeted the aorta, the software has the potential to describe the architecture of other fibrous materials, tube-like networks and connective tissues.

  19. Eruptive dermal clear cell desmo-plastic mesenchymal tumors with perivascular myoid differentiation in a young boy. A clinical, histopathologic, immunohistochemical and electron microscopy study of 17 lesions.

    Science.gov (United States)

    Tomasini, Carlo; Metze, Dieter; Osella-Abate, Simona; Novelli, Mauro; Kutzner, Heinz

    2014-02-01

    Clear cell tumors of the skin are observed in a wide variety of benign and malignant conditions with different histogenesis, sharing the presence of cells with abundant clear cytoplasm. Herein, we report the clinicopathologic features of a healthy young patient affected by asymptomatic, eruptive and disseminated, benign clear cell dermal tumors since early infancy. Neither family history nor genetic testing and counseling provided further useful information. The lesions were mostly confined to the face and lower left extremity with pink teleangiectatic papules and small nodules. Over a 4-year period, a total of 16 different cutaneous lesions were biopsied and histopathologic and immunohistochemical studies carried out; an additional lesion was also removed for electron microscopy examination. Histopathology evidenced multiple perivascular growths of spindle to oval and round cells intermingled with clear/granular cells throughout the dermis, with prominent desmoplasia and numerous capillary-like vessels with focal hemangiopericytoma-like features. Immunohistochemical neoplastic cells were uniformly positive for h-caldesmon and focally smooth muscle α-actin and CD13 indicating myoid differentiation whereas the consistent diffuse cytoplasmic staining for lysosome antigen, such as CD68PG-M1 and NKI/C3 along with the ultrastructural findings supported the view of a lysosome-mediated apoptotic process. The differential diagnosis with other clear cell cutaneous neoplasms is discussed.

  20. By Laser Confocal Microscopy Observed Clinical Efficacy of Fungal Keratitis%共焦显微镜对真菌性角膜炎药物治疗后转归的临床观察

    Institute of Scientific and Technical Information of China (English)

    张秀娟; 李雪丽; 勾晓梅; 周丽霞; 谷万章

    2015-01-01

    Objective To investigate the clinical observation of fungal keratitis after drug treatment outcomes with confocal microscopy.Methods 32 patients (32 eyes) with fungal keratitis hospitalized patients given anti -drug treat-ment of fungal keratitis in treated 2 w, 4 w, 8 w, respectively , for patients confocal microscopy , depending on the num-ber of fungal hyphae , size, clinical signs adjust medication.Results All of patients were cured 28 cases, varying de-grees of visual acuity improved after treatment in 8w to review confocal microscopy , the patient′s condition is stable , only see a small amount of fungal hyphae or fungal hyphae completely subsided , visible scar -like changes , 4 cases of the disease after treatment 2 w deterioration, corneal perforation, final enucleation after treatment , the total effective rate was 87.5%, with statistical significance (P<0.05).Conclusions Confocal microscopy as a non -invasive treatment meth-ods, can be used as medication guide fungal keratitis an objective examination tool .%目的:探讨共焦显微镜对真菌性角膜炎药物治疗后转归的临床观察。方法32例(32只眼)真菌性角膜炎的住院患者给予抗真菌性角膜炎药物治疗,在接受治疗的2w、4w、8w分别对患者进行共焦显微镜检查,根据真菌菌丝的数量、大小,临床体征调整用药。结果32例患者中28例治愈,视力不同程度提高,在治疗2月后复查共焦显微,患者病情稳定,仅见少量真菌菌丝或真菌菌丝完全消退,可见疤痕样改变,4例治疗2周后病情恶化,角膜穿孔,最终眼球摘除,治疗后总有效率为87.5%,有统计学意义( P<0.05)。结论共焦显微镜作为一种无创伤性诊疗手段,可作为指导真菌性角膜炎药物治疗的一种客观检查工具。

  1. Comparison of confocal microscopy and two-photon microscopy in mouse cornea in vivo.

    Science.gov (United States)

    Lee, Jun Ho; Lee, Seunghun; Gho, Yong Song; Song, In Seok; Tchah, Hungwon; Kim, Myoung Joon; Kim, Ki Hean

    2015-03-01

    High-resolution imaging of the cornea is important for studying corneal diseases at cellular levels. Confocal microscopy (CM) has been widely used in the clinic, and two-photon microscopy (TPM) has recently been introduced in various pre-clinical studies. We compared the performance of CM and TPM in normal mouse corneas and neovascularized mouse corneas induced by suturing. Balb/C mice and C57BL/6 mice expressing green fluorescent protein (GFP) were used to compare modalities based on intrinsic contrast and extrinsic fluorescence contrast. CM based on reflection (CMR), CM based on fluorescence (CMF), and TPM based on intrinsic/extrinsic fluorescence and second harmonic generation (SHG) were compared by imaging the same sections of mouse corneas sequentially in vivo. In normal mouse corneas, CMR visualized corneal cell morphologies with some background noise, and CMF visualized GFP expressing corneal cells clearly. TPM visualized corneal cells and collagen in the stroma based on fluorescence and SHG, respectively. However, in neovascularized mouse corneas, CMR could not resolve cells deep inside the cornea due to high background noise from the effects of increased structural irregularity induced by suturing. CMF and TPM visualized cells and induced vasculature better than CMR because both collect signals from fluorescent cells only. Both CMF and TPM had signal decays with depth due to the structural irregularity, with CMF having faster signal decay than TPM. CMR, CMF, and TPM showed different degrees of image degradation in neovascularized mouse corneas.

  2. [Evidence-based clinical guidelines in dental practice 6. Guidelines for clinical practice in dental education].

    Science.gov (United States)

    van der Sanden, W J M; Gorter, R; Tams, J

    2015-09-01

    In response to the initiatives of the Kennisinstituut Mondzorg (Institute for Knowledge Translation in Oral Care), the importance of effective education in the area of guidelines is increasing. Future dentists will, after all, be confronted with new guidelines and need to be able to integrate them in their daily practice. Various guidelines and protocols have been established within the 3 dental schools. For students and instructors, however, the motivation for these guidelines and protocols is not always sufficiently clear. In addition, the terms guideline, clinical practice guideline and protocol are used interchangeably, resulting in terminological confusion. Embedding within and coordination with theoretical education is also still limited in all programmes and it is proposed that the 3 dental schools collaborate on this issue. Finally, it is advised to replace the term 'evidence-based' with 'evidence-informed' because this indicates more clearly that other factors (patients opinion, available financial means, etc.) play a role in the final choice of treatment in a specific situation.

  3. 基于时间相关单光子计数的离线式g-STED超分辨显微术%Super Resolution Microscopy of Offline g-STED Microscopy Based on Time-Correlated Single Photon Counting

    Institute of Scientific and Technical Information of China (English)

    郝翔; 匡翠方; 顾兆泰; 李帅; 刘旭

    2013-01-01

    提出了一种离线式基于时间门的荧光受激发射损耗(g-STED)显微方法.基于在强光照条件下荧光寿命缩短的理论模型,在常规STED架构基础上,使用时间相关单光子记数(TCSPC)算法获取图像的荧光寿命信息,离线设置合理的时间门阈值,丢弃短寿命信号数据,对荧光信号有效点扩展函数(PSF)进行压缩,达到超分辨显微的目的.与传统STED显微术相比,此方法所需光功率大幅度降低,减少了荧光漂白及光毒性;离线式处理则同时增加了时间门设置的灵活性.在实验中,使用45 rnW的连续STED光,最终获取了约80 nm的图像空间分辨率.进一步对时间门的设置对获取图像信号的分辨率和信噪比的影响进行了讨论.%The offline time-gated stimulated emission depletion (g-STED) microscopy, which is based on time-correlated single photon counting (TCSPC) algorithm, is proposed. As STED beam can eliminate the ratio of spontaneous fluorescent emission while reducing the fluorescence lifetime, the lifetime of fluorescent signals in the center of excitation focal spot and that in the surrounding doughnut area which are overlap by the STED focal spot are significant different. Based on this principle, in a general continuous wave STED (CW-STED), the fluorescent lifetimes of the whole imaging region are calculated by TCSPC, and the signals with shorter lifetime are discarded after all data recorded. The effective point spread function (PSF) of each fluorescent labels are shrinked in order to enhance the resolution. Compared with traditional ones, this offline g-STED not only decreases the incident intensity of laser to avoid the risk of fluorescence photobleaching and optical toxicity, but also increases the flexibility of time-gate manipulation. A spatial resolution of 80 nm is obtained in the experiment when only 45 mW STED beam is introduced. The potential influences of time-gate selection to the resolution and signal-to-noise ratio

  4. Image scanning microscopy with radially polarized light

    Science.gov (United States)

    Xiao, Yun; Zhang, Yunhai; Wei, Tongda; Huang, Wei; Shi, Yaqin

    2017-03-01

    In order to improve the resolution of image scanning microscopy, we present a method based on image scanning microscopy and radially polarized light. According to the theory of image scanning microscopy, we get the effective point spread function of image scanning microscopy with the longitudinal component of radially polarized light and a 1 AU detection area, and obtain imaging results of the analyzed samples using this method. Results show that the resolution can be enhanced by 7% compared with that in image scanning microscopy with circularly polarized light, and is 1.54-fold higher than that in confocal microscopy with a pinhole of 1 AU. Additionally, the peak intensity of ISM is 1.54-fold higher than that of a confocal microscopy with a pinhole of 1 AU. In conclusion, the combination of the image scanning microscopy and the radially polarized light could improve the resolution, and it could realize high-resolution and high SNR imaging at the same time.

  5. Technology for nanoelectronic devices based on ultra-high vacuum scanning tunneling microscopy on the Si(100) surface

    NARCIS (Netherlands)

    Palasantzas, G; Ilge, B; Rogge, S; Geerlings, LJ

    1999-01-01

    We describe two process steps in an STM-based fabrication technology for nanoelectronic devices. First, we have fabricated Co/Si metal lines on Si(100) surfaces by UHV-STM based nanolithography on a monohydride passivation layer. The STM tip was used to define depassivated lines (

  6. Significance of Evidence-based Medicine in the Assessment of Chinese Medicine Clinical Efficacy

    Institute of Scientific and Technical Information of China (English)

    WANG Ji-yao

    2010-01-01

    @@ Evidence-based medicine (EBM) requires the integration of the best research evidence with our clinical expertise and our patient's unique values and circumstances.The best evidence is valid and clinically relevant,especially from patient-centered clinical research.The clinical expertise means the ability to use our clinical skills and past experiences to rapidly identify each patient's unique health state and diagnosis,their individual risks,and the benefits of interventions (1)..

  7. Construction of a shared system-based real-world clinical research system.

    Science.gov (United States)

    Wu, Huikun; Li, Xiaodong; Yang, Fan; Xie, Dan; Li, Hui; Huang, Jingjing; Guo, Mingxing

    2014-09-01

    Hubei Provincial Hospital of Traditional Chinese Medicine established research outpatient clinics to contribute to the major disease-entity research conducted by the National Traditional Chinese Medicine Clinical Research Base and to the construction of the National Traditional Chinese Medicine Treatment and Clinical Research Information Sharing System. With a view of developing a "real-world traditional Chinese medicine clinical research paradigm," these clinics explored the mode of constructing research outpatient clinics from the aspects of clinical research, health management, and characteristics diagnosis and treatment.

  8. Membranes and Fluorescence microscopy

    DEFF Research Database (Denmark)

    Bagatolli, Luis

    2009-01-01

    be provided by microscopy-related techniques. In this chapter, I will attempt to summarize representative examples concerning how microscopy (which provides information on membrane lateral organization by direct visualization) and spectroscopy techniques (which provides information about molecular interaction...

  9. Towards knowledge-based systems in clinical practice: development of an integrated clinical information and knowledge management support system.

    Science.gov (United States)

    Kalogeropoulos, Dimitris A; Carson, Ewart R; Collinson, Paul O

    2003-09-01

    Given that clinicians presented with identical clinical information will act in different ways, there is a need to introduce into routine clinical practice methods and tools to support the scientific homogeneity and accountability of healthcare decisions and actions. The benefits expected from such action include an overall reduction in cost, improved quality of care, patient and public opinion satisfaction. Computer-based medical data processing has yielded methods and tools for managing the task away from the hospital management level and closer to the desired disease and patient management level. To this end, advanced applications of information and disease process modelling technologies have already demonstrated an ability to significantly augment clinical decision making as a by-product. The wide-spread acceptance of evidence-based medicine as the basis of cost-conscious and concurrently quality-wise accountable clinical practice suffices as evidence supporting this claim. Electronic libraries are one-step towards an online status of this key health-care delivery quality control environment. Nonetheless, to date, the underlying information and knowledge management technologies have failed to be integrated into any form of pragmatic or marketable online and real-time clinical decision making tool. One of the main obstacles that needs to be overcome is the development of systems that treat both information and knowledge as clinical objects with same modelling requirements. This paper describes the development of such a system in the form of an intelligent clinical information management system: a system which at the most fundamental level of clinical decision support facilitates both the organised acquisition of clinical information and knowledge and provides a test-bed for the development and evaluation of knowledge-based decision support functions.

  10. Teaching clinical reasoning: case-based and coached.

    Science.gov (United States)

    Kassirer, Jerome P

    2010-07-01

    Optimal medical care is critically dependent on clinicians' skills to make the right diagnosis and to recommend the most appropriate therapy, and acquiring such reasoning skills is a key requirement at every level of medical education. Teaching clinical reasoning is grounded in several fundamental principles of educational theory. Adult learning theory posits that learning is best accomplished by repeated, deliberate exposure to real cases, that case examples should be selected for their reflection of multiple aspects of clinical reasoning, and that the participation of a coach augments the value of an educational experience. The theory proposes that memory of clinical medicine and clinical reasoning strategies is enhanced when errors in information, judgment, and reasoning are immediately pointed out and discussed. Rather than using cases artificially constructed from memory, real cases are greatly preferred because they often reflect the false leads, the polymorphisms of actual clinical material, and the misleading test results encountered in everyday practice. These concepts foster the teaching and learning of the diagnostic process, the complex trade-offs between the benefits and risks of diagnostic tests and treatments, and cognitive errors in clinical reasoning. The teaching of clinical reasoning need not and should not be delayed until students gain a full understanding of anatomy and pathophysiology. Concepts such as hypothesis generation, pattern recognition, context formulation, diagnostic test interpretation, differential diagnosis, and diagnostic verification provide both the language and the methods of clinical problem solving. Expertise is attainable even though the precise mechanisms of achieving it are not known.

  11. Cramér-Rao Lower Bound for Point Based Image Registration With Heteroscedastic Error Model for Application in Single Molecule Microscopy.

    Science.gov (United States)

    Cohen, E A K; Kim, D; Ober, R J

    2015-12-01

    The Cramér-Rao lower bound for the estimation of the affine transformation parameters in a multivariate heteroscedastic errors-in-variables model is derived. The model is suitable for feature-based image registration in which both sets of control points are localized with errors whose covariance matrices vary from point to point. With focus given to the registration of fluorescence microscopy images, the Cramér-Rao lower bound for the estimation of a feature's position (e.g., of a single molecule) in a registered image is also derived. In the particular case where all covariance matrices for the localization errors are scalar multiples of a common positive definite matrix (e.g., the identity matrix), as can be assumed in fluorescence microscopy, then simplified expressions for the Cramér-Rao lower bound are given. Under certain simplifying assumptions these expressions are shown to match asymptotic distributions for a previously presented set of estimators. Theoretical results are verified with simulations and experimental data.

  12. An Integrative Pathway-based Clinical-genomic Model for Cancer Survival Prediction.

    Science.gov (United States)

    Chen, Xi; Wang, Lily; Ishwaran, Hemant

    2010-09-01

    Prediction models that use gene expression levels are now being proposed for personalized treatment of cancer, but building accurate models that are easy to interpret remains a challenge. In this paper, we describe an integrative clinical-genomic approach that combines both genomic pathway and clinical information. First, we summarize information from genes in each pathway using Supervised Principal Components (SPCA) to obtain pathway-based genomic predictors. Next, we build a prediction model based on clinical variables and pathway-based genomic predictors using Random Survival Forests (RSF). Our rationale for this two-stage procedure is that the underlying disease process may be influenced by environmental exposure (measured by clinical variables) and perturbations in different pathways (measured by pathway-based genomic variables), as well as their interactions. Using two cancer microarray datasets, we show that the pathway-based clinical-genomic model outperforms gene-based clinical-genomic models, with improved prediction accuracy and interpretability.

  13. Imaging of Pseudo Oil Base Mud in Environmental Scanning Electron Microscopy Imagerie des boues de forage à base d'huile de substitution par microscopie électronique à balayage ambiant

    Directory of Open Access Journals (Sweden)

    Tricart J. P.

    2006-12-01

    Full Text Available Characterizing pseudo oil base muds (POBM amounts to determining the relationships between the size distribution of droplets and stability of emulsions. Conventional scanning and transmission electron microscope (SEM and TEM have been used to investigate these problems. However, hydrated samples are difficult to handle using such techniques. The Environmental Scanning Electron Microscope (ESEM or Electroscan and the cryogenic techniques have opened the door to the study of wet and non-conductive specimens, and of various liquids or emulsions. ESEM with the cold stage allows us to directly visualize emulsions :- without any preparation or coating;- at different temperatures, by controlling the specimen temperature (between -180°C and -8O°C and pressure (between 400 and 1400 Pa. La caractérisation des boues de forage à base d'huile de substitution (POBM équivaut à définir la relation entre la répartition dimensionnelle des gouttelettes et la stabilité des émulsions. Les microscopes électroniques à balayage (SEM et à transmission (TEM classiques ont été utilisés pour étudier ces problèmes. Toutefois, les échantillons hydratés sont d'un traitement difficile à l'aide de ces techniques. Le microscope environnemental électronique à balayage (ESEM ou electroscan et les techniques cryogéniques ont ouvert la voie à l'étude de spécimens humides et non conducteurs, de liquides et d'émulsions divers. A froid, l'ESEM nous permet de visualiser des émulsions : - sans aucune préparation ou enrobage, - à différentes températures, en régulant la température (entre - 180°C et - 80°C et la pression (entre 400 et 1400 kPa du spécimen. Le présent document se propose de caractériser les boues à base d'huile de substitution et d'étudier : - l'homogénéité de la formulation et la procédure de préparation, - l'influence de la répartition dimensionnelle des gouttelettes sur la stabilité des émulsions.

  14. Management of posttraumatic brain swelling based on clinical typing

    Institute of Scientific and Technical Information of China (English)

    刘伟国; 裘五四; 沈宏; 王卫民

    2004-01-01

    Objective: To investigate the clinical typing and prophylactico-therapeutic measures for acute posttraumatic brain swelling (BS).Methods: A retrospective study was performed in 66 cases of acute posttraumatic BS. There were 3 groups based on computered tomography (CT) scanning: 23 cases of hemisphere brain swelling (HBS) with middle line shift for less than 5 mm within 24 hours ( Group A), 20 with middle line shift for more than 5 mm (Group B ), and 23 with bilateral diffuse brain swelling (Group C).Results : (1) The mortality rates of the operative and nonoperative management in Group A, Group B, and Group C were 20.0%, 31.6%, and 75.0% versus 44.4%,0, and 85.7 %, respectively ( P > 0.05 ); while the rates in subgroups with different middle line shift ( more than 5 mm and less or equal 5 mm) were 29.2% and 75.0% versus 75.0% and 44.4%, respectively (0.05 >P >0.01). (2) The good recovery rate and mortality in Group A were 47.8 % and 39.1%, respectively and in Group C, 8.7 % and 78.3%, respectively. There was a very significant difference between Group A and Group C (P <0.01). (3) The total survival rate of the selective comprehensive therapy was 53.1%.Conclusions : ( 1 ) Acute posttraumatic BS needs to be diagnosed correctly and promptly with CT scanning within 4 hours. (2) For patients with midline shift for more than 5 mm, especially with thin-layered subdural hematoma,surgical intervention is essential to reduce the fatality of acute posttraumatic BS.

  15. Methyldibromo glutaronitrile: clinical experience and exposure-based risk assessment.

    Science.gov (United States)

    Zachariae, Claus; Rastogi, Suresh; Devantier, Charlotte; Menné, Torkil; Johansen, Jeanne Duus

    2003-03-01

    In the year 2000, the level of methyldibromo glutaronitrile (MDGN) allergy in dermatology clinics in Europe exceeded the level of allergies to all other preservatives, with a prevalence of 3.5%. In the present study, cases of primary sensitization and elicitation to MDGN due to cosmetic products were collected over an 8-month period at the Department of Dermatology, Gentofte University Hospital. The aim was to identify the products related to hand eczema, assess exposure to MDGN in these products and relate the findings to results from a newly developed updated risk assessment model for contact allergy. Out of 24 patients with a positive patch test to MDGN, 17 patients with hand eczema were identified. In 11 of these patients, cosmetic products used in relation to the onset of the disease were shown to contain MDGN (65%). In 8 of these 11 cases, primary sensitization was probable, 5 due to hand/body lotions and 3 due to lotions and/or liquid hand soap. Chemical analysis of 12 products showed that lotions contained 149-390 ppm of MDGN, liquid hand soap 144-399 ppm, a rinsing cream 293 ppm and shampoos 78-79 ppm. The shampoo exposure was not of certain relevance to the eczema. Applying the newly developed updated risk assessment model showed that the concentrations of MDGN in lotions of 149-390 ppm exceeded the calculated maximum acceptable exposure level for MDGN, which would be expected to lead to sensitization in consumers using such products, as seen in the current study. The present cases and updated exposure-based risk assessment process add to the evidence and need for re-defining safe-use concentrations of MDGN in cosmetic products.

  16. Recognition and Evaluation of Clinical Section Headings in Clinical Documents Using Token-Based Formulation with Conditional Random Fields

    Science.gov (United States)

    Dai, Hong-Jie; Syed-Abdul, Shabbir; Chen, Chih-Wei; Wu, Chieh-Chen

    2015-01-01

    Electronic health record (EHR) is a digital data format that collects electronic health information about an individual patient or population. To enhance the meaningful use of EHRs, information extraction techniques have been developed to recognize clinical concepts mentioned in EHRs. Nevertheless, the clinical judgment of an EHR cannot be known solely based on the recognized concepts without considering its contextual information. In order to improve the readability and accessibility of EHRs, this work developed a section heading recognition system for clinical documents. In contrast to formulating the section heading recognition task as a sentence classification problem, this work proposed a token-based formulation with the conditional random field (CRF) model. A standard section heading recognition corpus was compiled by annotators with clinical experience to evaluate the performance and compare it with sentence classification and dictionary-based approaches. The results of the experiments showed that the proposed method achieved a satisfactory F-score of 0.942, which outperformed the sentence-based approach and the best dictionary-based system by 0.087 and 0.096, respectively. One important advantage of our formulation over the sentence-based approach is that it presented an integrated solution without the need to develop additional heuristics rules for isolating the headings from the surrounding section contents. PMID:26380302

  17. Damage in nickel base superalloy: Influence of local parameters measured by electron backscattered diffraction and atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Risbet, M. [Laboratoire Roberval, UMR 6253 UTC-CNRS, Universite de Technologie de Compiegne, BP 20529-60205 Compiegne cedex (France)], E-mail: marion.risbet@utc.fr; Feaugas, X. [Laboratoire d' Etude des Materiaux en Milieux Agressifs, EA 3127, Universite de La Rochelle, 17000 La Rochelle cedex (France); Guillemer-Neel, C. [Laboratoire de Technologies Innovantes, EA 3899, IUT Genie Mecanique d' Amiens, 80025 Amiens Cedex (France); Clavel, M. [Laboratoire Mecanique des Sols, Structures et Materiaux, UMR 8579 CNRS, Ecole Centrale Paris, 92295 Chatenay-Malabry Cedex (France)

    2009-03-15

    The low-cycle fatigue behaviour of a nickel-based superalloy has been investigated with regard to its surface damage features. This alloy endures localized plastic deformation confined in slip bands emerging as extrusions. The correlations between damage, grain orientation, the Schmid factor of slip systems and the height of extrusions have been questioned. It is proved here that reaching a critical height value is not a sufficient condition for an extrusion to induce the apparition of a transgranular crack.

  18. Rule based Part of speech Tagger for Homoeopathy Clinical realm

    CERN Document Server

    Dwivedi, Sanjay K

    2011-01-01

    A tagger is a mandatory segment of most text scrutiny systems, as it consigned a s yntax class (e.g., noun, verb, adjective, and adverb) to every word in a sentence. In this paper, we present a simple part of speech tagger for homoeopathy clinical language. This paper reports about the anticipated part of speech tagger for homoeopathy clinical language. It exploit standard pattern for evaluating sentences, untagged clinical corpus of 20085 words is used, from which we had selected 125 sentences (2322 tokens). The problem of tagging in natural language processing is to find a way to tag every word in a text as a meticulous part of speech. The basic idea is to apply a set of rules on clinical sentences and on each word, Accuracy is the leading factor in evaluating any POS tagger so the accuracy of proposed tagger is also conversed.

  19. Quantitative composition determination at the atomic level using model-based high-angle annular dark field scanning transmission electron microscopy.

    Science.gov (United States)

    Martinez, G T; Rosenauer, A; De Backer, A; Verbeeck, J; Van Aert, S

    2014-02-01

    High angle annular dark field scanning transmission electron microscopy (HAADF STEM) images provide sample information which is sensitive to the chemical composition. The image intensities indeed scale with the mean atomic number Z. To some extent, chemically different atomic column types can therefore be visually distinguished. However, in order to quantify the atomic column composition with high accuracy and precision, model-based methods are necessary. Therefore, an empirical incoherent parametric imaging model can be used of which the unknown parameters are determined using statistical parameter estimation theory (Van Aert et al., 2009, [1]). In this paper, it will be shown how this method can be combined with frozen lattice multislice simulations in order to evolve from a relative toward an absolute quantification of the composition of single atomic columns with mixed atom types. Furthermore, the validity of the model assumptions are explored and discussed.

  20. Stenostomum cf. leucops (Platyhelminthes in Thailand: a surface observation using scanning electron microscopy and phylogenetic analysis based on 18S ribosomal DNA sequences

    Directory of Open Access Journals (Sweden)

    Arin Ngamniyom

    2016-02-01

    Full Text Available The genus Stenostomum contains small turbellaria that are widely distributed in freshwater environments worldwide. However, there are only rare reports or studies of this genus from Thailand. Therefore, the objective of this study was to report S. cf. leucops in Thailand collected from Pathum Thani Province. The worm morphology and surface topography using scanning electron microscopy were determined. Moreover, the phylogenetic tree of S. cf. leucops was analysed with 17 flatworms based on the 18S ribosomal DNA sequences. The phylogenetic relationship shared a common ancestry of Catenulida species, and S. cf. leucops displayed a monophyletic pattern within Stenostomum spp. The results of the morphological and molecular data are discussed. These results may increase the knowledge of freshwater microturbellarians in Thailand.

  1. Development of a scanning electrochemical microscopy-based micropipette and its application to analysis of topographic change of single-cell.

    Science.gov (United States)

    Hirano, Yu; Kowata, Keiko; Kodama, Mikie; Komatsu, Yasuo

    2013-08-01

    Scanning electrochemical microscopy (SECM) is useful for analyzing various cellular responses. We have combined a micropipette (MP) with SECM to perform quantitative solution delivery to single cells. In this system, since the concentrations of electrochemical mediators are changed by the volume of solution delivered from the MP, we constructed a feedback control system to regulate MP delivery by SECM-detected signals. Cellular responses induced by MP delivery could be monitored by the SECM, and cell apoptosis was successfully detected by adding a kinase inhibitor of two orders of magnitude less than what is required in the conventional method. The SECM-based MP can activate a target cell, requiring a minimal amount of agent, and can continually examine target cell responses. This system improves the accuracy of delivery from the MP and is useful for single-cell analysis.

  2. Achromatic and high-resolution full-field X-ray microscopy based on total-reflection mirrors.

    Science.gov (United States)

    Matsuyama, Satoshi; Emi, Yoji; Kino, Hidetoshi; Kohmura, Yoshiki; Yabashi, Makina; Ishikawa, Tetsuya; Yamauchi, Kazuto

    2015-04-20

    We developed an achromatic and high-resolution full-field X-ray microscope based on advanced Kirkpatrick-Baez mirror optics that comprises two pairs of elliptical mirrors and hyperbolic mirrors utilizing the total reflection of X-rays. Performance tests to investigate the spatial resolution and chromatic aberration were performed at SPring-8. The microscope clearly resolved the pattern with ~100-nm feature size. Imaging the pattern by changing the X-ray energy revealed achromatism in the wide energy range of 8-11 keV.

  3. Automated microscopy system for peripheral blood cells

    Science.gov (United States)

    Boev, Sergei F.; Sazonov, Vladimir V.; Kozinets, Gennady I.; Pogorelov, Valery M.; Gusev, Alexander A.; Korobova, Farida V.; Vinogradov, Alexander G.; Verdenskaya, Natalya V.; Ivanova, Irina A.

    2000-11-01

    The report describes the instrument ASPBS (Automated Screening of Peripheral Blood Cells) designed for an automated analysis of dry blood smears. The instrument is based on computer microscopy and uses dry blood smears prepared according to the standard Romanovskii-Giemza procedure. In comparison with the well-known flow cytometry systems, our instrument provides more detailed information and offers an opporunity of visualizing final results. The basic performances of the instrument are given. Software of this instrument is based on digital image processing and image recognition procedures. It is pointed out that the instrument can be used as a fairly universal tool in scientific research, public demonstrations, in medical treatment, and in medical education. The principle used as the basis of the instrument appeared adequate for creating an instrument version serviceable even during space flights where standard manual procedures and flow cytometry systems fail. The benefit of the use of the instrument in clinical laboratories is described.

  4. Determining the structure-mechanics relationships of dense microtubule networks with confocal microscopy and magnetic tweezers-based microrheology.

    Science.gov (United States)

    Yang, Yali; Valentine, Megan T

    2013-01-01

    The microtubule (MT) cytoskeleton is essential in maintaining the shape, strength, and organization of cells. Its spatiotemporal organization is fundamental for numerous dynamic biological processes, and mechanical stress within the MT cytoskeleton provides an important signaling mechanism in mitosis and neural development. This raises important questions about the relationships between structure and mechanics in complex MT structures. In vitro, reconstituted cytoskeletal networks provide a minimal model of cell mechanics while also providing a testing ground for the fundamental polymer physics of stiff polymer gels. Here, we describe our development and implementation of a broad tool kit to study structure-mechanics relationships in reconstituted MT networks, including protocols for the assembly of entangled and cross-linked MT networks, fluorescence imaging, microstructure characterization, construction and calibration of magnetic tweezers devices, and mechanical data collection and analysis. In particular, we present the design and assembly of three neodymium iron boron (NdFeB)-based magnetic tweezers devices optimized for use with MT networks: (1) high-force magnetic tweezers devices that enable the application of nano-Newton forces and possible meso- to macroscale materials characterization; (2) ring-shaped NdFeB-based magnetic tweezers devices that enable oscillatory microrheology measurements; and (3) portable magnetic tweezers devices that enable direct visualization of microscale deformation in soft materials under applied force.

  5. Population-based clinical decision support: a clinical and economic evaluation.

    Science.gov (United States)

    Eisenstein, Eric L; Anstrom, Kevin J; Edwards, Rex; Willis, Janese M; Simo, Jessica; Lobach, David F

    2012-01-01

    Governments are investing in health information technologies (HIT) to improve care quality and reduce medical costs. However, evidence of these benefits is limited. We conducted a randomized trial of three clinical decision support (CDS) interventions in 20,180 patients: email to care managers (n=3329), reports to primary care administrators (n=3368), letters to patients (n=3401), and controls (10,082). At 7-month follow-up, the letters to patients group had greater use of outpatient services and higher outpatient and total medical costs; whereas, the other groups had no change in clinical events or medical costs. As our CDS interventions were associated with no change or an increase in medical costs, it appears that investments in HIT without consideration for organizational context may not be sufficient to achieve improvements in clinical and economic outcomes.

  6. The Emerging Microbe Project: Developing Clinical Care Plans Based on Pathogen Identification and Clinical Case Studies.

    Science.gov (United States)

    O'Donnell, Lauren A; Perry, Michael W; Doup, Dane't R

    2015-12-01

    For many students in the health sciences, including doctor of pharmacy (PharmD) students, basic and clinical sciences often appear detached from each other. In the infectious disease field, PharmD students additionally struggle with mastering the diversity of microorganisms and the corresponding therapies. The objective of this study was to design an interdisciplinary project that integrates fundamental microbiology with clinical research and decision-making skills. The Emerging Microbe Project guided students through the identification of a microorganism via genetic sequence analysis. The unknown microbe provided the basis for a patient case that asked the student to design a therapeutic treatment strategy for an infected patient. Outside of lecture, students had two weeks to identify the pathogen using nucleotide sequences, compose a microbiology report on the pathogen, and recommend an appropriate therapeutic treatment plan for the corresponding clinical case. We hypothesized that the students would develop a better understanding of the interplay between basic microbiology and infectious disease clinical practice, and that they would gain confidence and skill in independently selecting appropriate antimicrobial therapies for a new disease state. The exercise was conducted with PharmD students in their second professional year of pharmacy school in a required infectious disease course. Here, we demonstrate that the Emerging Microbe Project significantly improved student learning through two assessment strategies (assignment grades and exam questions), and increased student confidence in clinical infectious disease practice. This exercise could be modified for other health sciences students or undergraduates depending upon the level of clinical focus required of the course.

  7. The Emerging Microbe Project: Developing Clinical Care Plans Based on Pathogen Identification and Clinical Case Studies

    Directory of Open Access Journals (Sweden)

    Lauren A. O'Donnell

    2015-08-01

    Full Text Available For many students in the health sciences, including doctor of pharmacy (PharmD students, basic and clinical sciences often appear detached from each other. In the infectious disease field, PharmD students additionally struggle with mastering the diversity of microorganisms and the corresponding therapies. The objective of this study was to design an interdisciplinary project that integrates fundamental microbiology with clinical research and decision-making skills. The Emerging Microbe Project guided students through the identification of a microorganism via genetic sequence analysis. The unknown microbe provided the basis for a patient case that asked the student to design a therapeutic treatment strategy for an infected patient. Outside of lecture, students had two weeks to identify the pathogen using nucleotide sequences, compose a microbiology report on the pathogen, and recommend an appropriate therapeutic treatment plan for the corresponding clinical case. We hypothesized that the students would develop a better understanding of the interplay between basic microbiology and infectious disease clinical practice, and that they would gain confidence and skill in independently selecting appropriate antimicrobial therapies for a new disease state. The exercise was conducted with PharmD students in their second professional year of pharmacy school in a required infectious disease course. Here, we demonstrate that the Emerging Microbe Project significantly improved student learning through two assessment strategies (assignment grades and exam questions, and increased student confidence in clinical infectious disease practice. This exercise could be modified for other health sciences students or undergraduates depending upon the level of clinical focus required of the course.

  8. A service oriented approach for guidelines-based clinical decision support using BPMN.

    Science.gov (United States)

    Rodriguez-Loya, Salvador; Aziz, Ayesha; Chatwin, Chris

    2014-01-01

    Evidence-based medical practice requires that clinical guidelines need to be documented in such a way that they represent a clinical workflow in its most accessible form. In order to optimize clinical processes to improve clinical outcomes, we propose a Service Oriented Architecture (SOA) based approach for implementing clinical guidelines that can be accessed from an Electronic Health Record (EHR) application with a Web Services enabled communication mechanism with the Enterprise Service Bus. We have used Business Process Modelling Notation (BPMN) for modelling and presenting the clinical pathway in the form of a workflow. The aim of this study is to produce spontaneous alerts in the healthcare workflow in the diagnosis of Chronic Obstructive Pulmonary Disease (COPD). The use of BPMN as a tool to automate clinical guidelines has not been previously employed for providing Clinical Decision Support (CDS).

  9. Performance-Based Assessment of Clinical Ethics Using an Objective Structured Clinical Examination.

    Science.gov (United States)

    Singer, Peter A.; And Others

    1996-01-01

    Final-year Ontario medical students (n=88) took a 4-station objective structured clinical examination (OSCE) using standardized patients and involving decisions to forgo life-sustaining treatment. Performance was scored on a checklist of behaviors unique to each case. Results indicated that because of low reliability, the OSCE is not a feasible…

  10. Saliva-based biosensors: noninvasive monitoring tool for clinical diagnostics.

    Science.gov (United States)

    Malon, Radha S P; Sadir, Sahba; Balakrishnan, Malarvili; Córcoles, Emma P

    2014-01-01

    Saliva is increasingly recognised as an attractive diagnostic fluid. The presence of various disease signalling salivary biomarkers that accurately reflect normal and disease states in humans and the sampling benefits compared to blood sampling are some of the reasons for this recognition. This explains the burgeoning research field in assay developments and technological advancements for the detection of various salivary biomarkers to improve clinical diagnosis, management, and treatment. This paper reviews the significance of salivary biomarkers for clinical diagnosis and therapeutic applications, with focus on the technologies and biosensing platforms that have been reported for screening these biomarkers.

  11. Saliva-Based Biosensors: Noninvasive Monitoring Tool for Clinical Diagnostics

    Directory of Open Access Journals (Sweden)

    Radha S. P. Malon

    2014-01-01

    Full Text Available Saliva is increasingly recognised as an attractive diagnostic fluid. The presence of various disease signalling salivary biomarkers that accurately reflect normal and disease states in humans and the sampling benefits compared to blood sampling are some of the reasons for this recognition. This explains the burgeoning research field in assay developments and technological advancements for the detection of various salivary biomarkers to improve clinical diagnosis, management, and treatment. This paper reviews the significance of salivary biomarkers for clinical diagnosis and therapeutic applications, with focus on the technologies and biosensing platforms that have been reported for screening these biomarkers.

  12. [Clinical-metabolic data base on chronic generalized parodontitis].

    Science.gov (United States)

    Gil'miiarov, E M; Berezhnoĭ, V P; Gil'miiarova, I E; Tlustenko, V P

    2008-01-01

    As the result of clinical-lab study of 40 oral fluid parameters in 176 patients new block of data was received disclosing key pathogenetic links of chronic generalized parodontitis (CGP) to which could be attributed endocrine dysfunction with cortisol level reduction and free thyroid hormones increase, enforcing prooxidant processes with multiple iron content increase. As the result of it molecules of medium mass were accumulated; protein spectrum, protein coupling capacity, content of collagenous C-peptide, osteocalcine, Ca, P and Mg were changing. In comprehensive CGP treatment due to Natursyl (lipophilic fraction of holy thistle) applications the disease clinical signs disappeared quicker and biochemical markers normalized.

  13. Are the outcomes of clinical pathways evidence-based? A critical appraisal of clinical pathway evaluation research

    NARCIS (Netherlands)

    El Baz, N.; Middel, B.; Van Dijk, J.P.; Oosterhof, A.; Boonstra, P.W.; Reijneveld, S.A.

    2007-01-01

    Aim and objective To evaluate the validity of study outcomes of published papers that report the effects of clinical pathways (CP). Method Systematic review based on two search strategies, including searching Medline, CINAHL, Embase, Psychinfo and Picarta from 1995 till 2005 and ISI Web of Knowledge

  14. 3D -Ray Diffraction Microscopy

    DEFF Research Database (Denmark)

    Poulsen, Henning Friis; Schmidt, Søren; Juul Jensen, Dorte

    2014-01-01

    Three-dimensional X-ray diffraction (3DXRD) microscopy is a fast and non-destructive structural characterization technique aimed at the study of individual crystalline elements (grains or subgrains) within mm-sized polycrystalline specimens. It is based on two principles: the use of highly penetr...

  15. New microscopy for nanoimaging

    CERN Document Server

    Kinjo, Y; Watanabe, M

    2002-01-01

    Two types of new microscopy, namely, X-ray contact microscopy (XRCM) in combination with atomic force microscopy (AFM) and X-ray projection microscopy (XRPM) using synchrotron radiation and zone plate optics were used to image the fine structures of human chromosomes. In the XRCM plus AFM system, location of X-ray images on a photoresist has become far easier than that with our previous method using transmission electron microscopy coupled with the replica method. In addition, the images obtained suggested that the conformation of chromatin fiber differs from the current textbook model regarding the architecture of a eukaryotic chromosome. X-ray images with high contrast of the specimens could be obtained with XRPM. The resolution of each microscopy was about 30 and 200-300 nm for XRCM plus AFM and XRPM, respectively. (author)

  16. Clinical study of model-based blood flow quantification on cerebrovascular data

    NARCIS (Netherlands)

    Groth, A.; Wächter-Stehle, I.; Brina, O.; Perren. F.; Rüfenacht, D.; Bruijns, T.; Bertram, M.; Weese, J.

    2011-01-01

    Diagnosis and treatment decisions of cerebrovascular diseases are currently based on structural information like the endovascular lumen. In future, clinical diagnosis will increasingly be based on functional information which gives direct information about the physiological parameters and, hence, is

  17. Three-dimensional block-based restoration integrated with wide-field fluorescence microscopy for the investigation of thick specimens with spatially variant refractive index.

    Science.gov (United States)

    Ghosh, Sreya; Preza, Chrysanthe

    2016-04-30

    Development of a block-based restoration (BBR) method that addresses spatially variant (SV) imaging in wide-field fluorescence microscopy of thick samples is presented. The BBR method is based on a block-based imaging model, which approximates SV imaging using an efficient orthonormal basis decomposition of multiple SV point-spread functions computed at block vertices. The effect of reducing the number of blocks needed to account for SV imaging on the restoration accuracy was investigated with simulations using a numerical lung tissue phantom relevant to biological studies. Results show that reducing the number of blocks by 82% and 98% resulted in a 19% and 27% reduction in restoration accuracy, respectively, thereby establishing a reasonable tradeoff between computational resources and accuracy. Comparison of the BBR method to existing methods (deconvolution) that do not account for SV imaging demonstrates a 90% improvement in restoration accuracy. BBR results from synthetic and experimental images of a controlled test sample with SV refractive index (RI) show consistency, providing a validation of the BBR approach. In this study, information from DIC and fluorescence images was combined to identify regions with changing RI within the imaging volume. The BBR method provides a first step toward computationally tractable reconstruction of images from thick samples.

  18. Computer-aided screening system for cervical precancerous cells based on field emission scanning electron microscopy and energy dispersive x-ray images and spectra

    Science.gov (United States)

    Jusman, Yessi; Ng, Siew-Cheok; Hasikin, Khairunnisa; Kurnia, Rahmadi; Osman, Noor Azuan Bin Abu; Teoh, Kean Hooi

    2016-10-01

    The capability of field emission scanning electron microscopy and energy dispersive x-ray spectroscopy (FE-SEM/EDX) to scan material structures at the microlevel and characterize the material with its elemental properties has inspired this research, which has developed an FE-SEM/EDX-based cervical cancer screening system. The developed computer-aided screening system consisted of two parts, which were the automatic features of extraction and classification. For the automatic features extraction algorithm, the image and spectra of cervical cells features extraction algorithm for extracting the discriminant features of FE-SEM/EDX data was introduced. The system automatically extracted two types of features based on FE-SEM/EDX images and FE-SEM/EDX spectra. Textural features were extracted from the FE-SEM/EDX image using a gray level co-occurrence matrix technique, while the FE-SEM/EDX spectra features were calculated based on peak heights and corrected area under the peaks using an algorithm. A discriminant analysis technique was employed to predict the cervical precancerous stage into three classes: normal, low-grade intraepithelial squamous lesion (LSIL), and high-grade intraepithelial squamous lesion (HSIL). The capability of the developed screening system was tested using 700 FE-SEM/EDX spectra (300 normal, 200 LSIL, and 200 HSIL cases). The accuracy, sensitivity, and specificity performances were 98.2%, 99.0%, and 98.0%, respectively.

  19. Rapid imaging, detection and quantification of Giardia lamblia cysts using mobile-phone based fluorescent microscopy and machine learning.

    Science.gov (United States)

    Koydemir, Hatice Ceylan; Gorocs, Zoltan; Tseng, Derek; Cortazar, Bingen; Feng, Steve; Chan, Raymond Yan Lok; Burbano, Jordi; McLeod, Euan; Ozcan, Aydogan

    2015-03-07

    efficiency of ~79% on our filter membrane along with a machine learning based cyst counting sensitivity of ~84%, yielding a limit-of-detection of ~12 cysts per 10 mL. Providing rapid detection and quantification of microorganisms, this field-portable imaging and sensing platform running on a mobile-phone could be useful for water quality monitoring in field and resource-limited settings.

  20. In situ and operando atomic force microscopy of high-capacity nano-silicon based electrodes for lithium-ion batteries

    Science.gov (United States)

    Breitung, Ben; Baumann, Peter; Sommer, Heino; Janek, Jürgen; Brezesinski, Torsten

    2016-07-01

    Silicon is a promising next-generation anode material for high-energy-density lithium-ion batteries. While the alloying of nano- and micron size silicon with lithium is relatively well understood, the knowledge of mechanical degradation and structural rearrangements in practical silicon-based electrodes during operation is limited. Here, we demonstrate, for the first time, in situ and operando atomic force microscopy (AFM) of nano-silicon anodes containing polymer binder and carbon black additive. With the help of this technique, the surface topography is analyzed while electrochemical reactions are occurring. In particular, changes in particle size as well as electrode structure and height are visualized with high resolution. Furthermore, the formation and evolution of the solid-electrolyte interphase (SEI) can be followed and its thickness determined by phase imaging and nano-indentation, respectively. Major changes occur in the first lithiation cycle at potentials below 0.6 V with respect to Li/Li+ due to increased SEI formation - which is a dynamic process - and alloying reactions. Overall, these results provide insight into the function of silicon-based composite electrodes and further show that AFM is a powerful technique that can be applied to important battery materials, without restriction to thin film geometries.Silicon is a promising next-generation anode material for high-energy-density lithium-ion batteries. While the alloying of nano- and micron size silicon with lithium is relatively well understood, the knowledge of mechanical degradation and structural rearrangements in practical silicon-based electrodes during operation is limited. Here, we demonstrate, for the first time, in situ and operando atomic force microscopy (AFM) of nano-silicon anodes containing polymer binder and carbon black additive. With the help of this technique, the surface topography is analyzed while electrochemical reactions are occurring. In particular, changes in particle

  1. Photothermal Single Particle Microscopy

    OpenAIRE

    Selmke, Markus; Braun, Marco; Cichos, Frank

    2011-01-01

    Photothermal microscopy has recently complemented single molecule fluorescence microscopy by the detection of individual nano-objects in absorption. Photothermal techniques gain their superior sensitivity by exploiting a heat induced refractive index change around the absorbing nano-object. Numerous new applications to nanoparticles, nanorods and even single molecules have been reported all refering to the fact that photothermal microscopy is an extinction measurement on a heat induced refrac...

  2. A Semantic Web-based System for Managing Clinical Archetypes.

    Science.gov (United States)

    Fernandez-Breis, Jesualdo Tomas; Menarguez-Tortosa, Marcos; Martinez-Costa, Catalina; Fernandez-Breis, Eneko; Herrero-Sempere, Jose; Moner, David; Sanchez, Jesus; Valencia-Garcia, Rafael; Robles, Montserrat

    2008-01-01

    Archetypes facilitate the sharing of clinical knowledge and therefore are a basic tool for achieving interoperability between healthcare information systems. In this paper, a Semantic Web System for Managing Archetypes is presented. This system allows for the semantic annotation of archetypes, as well for performing semantic searches. The current system is capable of working with both ISO13606 and OpenEHR archetypes.

  3. Analysis of quality data based on national clinical databases

    DEFF Research Database (Denmark)

    Utzon, Jan; Petri, A.L.; Christophersen, S.

    2009-01-01

    There is little agreement on the philosophy of measuring clinical quality in health care. How data should be analyzed and transformed to healthcare information is an ongoing discussion. To accept a difference in quality between health departments as a real difference, one should consider to which...... is understandable to readers without specialised knowledge of statistics Udgivelsesdato: 2009/9/14...

  4. Vaccine-based clinical trials in ovarian cancer

    NARCIS (Netherlands)

    Leffers, Ninke; Daemen, Toos; Boezen, H. Marike; Melief, Kees J. M.; Nijman, Hans W.

    2011-01-01

    Ovarian cancer vaccines are one of the new treatment strategies under investigation in epithelial ovarian cancer. This article discusses the results of different immunization strategies, points out potential pitfalls in study designs and provides possible solutions for augmentation of clinical effic

  5. A comprehensive clinical competency-based assessment in periodontics.

    Science.gov (United States)

    Shiloah, J; Scarbecz, M; Bland, P S; Hottel, T L

    2017-05-01

    Traditional periodontics clinical examinations in dental education frequently assess a narrow set of clinical skills and do not adequately assess the ability of students to independently manage a periodontal patient. As an alternative, the authors developed a comprehensive periodontics competency case experience (CCCE) for senior dental students and surveyed students regarding their experience with the CCCE. Students challenging the CCCE must treat a patient with moderate periodontitis and must independently decide when a state of periodontal and oral health has been achieved. Students are also required to conduct an oral presentation to periodontology faculty. Dental students who completed the CCCE had a favourable impression of the experience, compared with the traditional clinical examinations taken in the junior year. The majority of students rated all the components of the CCCE as 'somewhat' or 'very helpful'. About 72.4% of students felt that being able to work independently on the examination was very helpful for learning about the clinical management of patients with periodontal disease, followed by 'simulation of care in private practice' (65.5%), and oral photography experience (55.2%). The greatest difficulty reported by students was finding an acceptable patient. About 62.1% of students rated 'finding the right patient' as very difficult. Students reported having to screen a mean of 5.9 patients (SD: 4.5) to find a qualified patient. The results of the survey will be useful in improving the examination as an assessment tool in periodontal therapy.

  6. An Exploration of the Base Rate Scores of the Millon Clinical Multiaxial Inventory-III

    Science.gov (United States)

    Grove, William M.; Vrieze, Scott I.

    2009-01-01

    The Millon Clinical Multiaxial Inventory (3rd ed.; MCMI-III) is a widely used psychological assessment of clinical and personality disorders. Unlike typical tests, the MCMI-III uses a base-rate score transformation to incorporate prior probabilities of disorder (i.e., base rates) in test output and diagnostic thresholds. The authors describe the…

  7. A Comparison of Urban School- and Community-Based Dental Clinics

    Science.gov (United States)

    Larsen, Charles D.; Larsen, Michael D.; Handwerker, Lisa B.; Kim, Maile S.; Rosenthal, Murray

    2009-01-01

    Background: The objective of the study was to quantitatively compare school- and community-based dental clinics in New York City that provide dental services to children in need. It was hypothesized that the school-based clinics would perform better in terms of several measures. Methods: We reviewed billing and visit data derived from encounter…

  8. Developing Clinical Competency in Crisis Event Management: An Integrated Simulation Problem-Based Learning Activity

    Science.gov (United States)

    Liaw, S. Y.; Chen, F. G.; Klainin, P.; Brammer, J.; O'Brien, A.; Samarasekera, D. D.

    2010-01-01

    This study aimed to evaluate the integration of a simulation based learning activity on nursing students' clinical crisis management performance in a problem-based learning (PBL) curriculum. It was hypothesized that the clinical performance of first year nursing students who participated in a simulated learning activity during the PBL session…

  9. Bridging fluorescence microscopy and electron microscopy

    NARCIS (Netherlands)

    Giepmans, Ben N. G.

    2008-01-01

    Development of new fluorescent probes and fluorescence microscopes has led to new ways to study cell biology. With the emergence of specialized microscopy units at most universities and research centers, the use of these techniques is well within reach for a broad research community. A major breakth

  10. Coherent light microscopy

    CERN Document Server

    Ferraro, Pietro; Zalevsky, Zeev

    2011-01-01

    This book deals with the latest achievements in the field of optical coherent microscopy. While many other books exist on microscopy and imaging, this book provides a unique resource dedicated solely to this subject. Similarly, many books describe applications of holography, interferometry and speckle to metrology but do not focus on their use for microscopy. The coherent light microscopy reference provided here does not focus on the experimental mechanics of such techniques but instead is meant to provide a users manual to illustrate the strengths and capabilities of developing techniques. Th

  11. Electron Microscopy Center (EMC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Electron Microscopy Center (EMC) at Argonne National Laboratory develops and maintains unique capabilities for electron beam characterization and applies those...

  12. [Artefacts of confocal microscopy].

    Science.gov (United States)

    Vekshin, N L; Frolov, M S

    2014-01-01

    Typical artefacts caused by using confocal fluorescent microscopy while studying living cells are considered. The role of light scattering, mobility, staining, local concentrations, etc. is discussed.

  13. [The historical background and present development of evidence-based healthcare and clinical nursing].

    Science.gov (United States)

    Tsai, Jung-Mei

    2014-12-01

    Evidence-based healthcare (EBHC) emphasizes the integration of the best research evidence with patient values, specialist suggestions, and clinical circumstances during the process of clinical decision-making. EBHC is a recognized core competency in modern healthcare. Nursing is a professional discipline of empirical science that thrives in an environment marked by advances in knowledge and technology in medicine as well as in nursing. Clinical nurses must elevate their skills and professional qualifications, provide efficient and quality health services, and promote their proficiency in EBHC. The Institute of Medicine in the United States indicates that evidence-based research results often fail to disseminate efficiently to clinical decision makers. This problem highlights the importance of better promoting the evidence-based healthcare fundamentals and competencies to frontline clinical nurses. This article describes the historical background and present development of evidence-based healthcare from the perspective of modern clinical nursing in light of the importance of evidence-based healthcare in clinical nursing; describes the factors associated with evidence-based healthcare promotion; and suggests strategies and policies that may improve the promotion and application of EBHC in clinical settings. The authors hope that this paper provides a reference for efforts to improve clinical nursing in the realms of EBHC training, promotion, and application.

  14. Development of Clinic Specific Physical Therapy Efficiency Targets Based on Clinic Specific Metrics

    Science.gov (United States)

    2009-04-24

    efficiency ratings in the PBAM model which inflates the monetary budget adjustment for the MTF under the orthopedic product line. Developing individual... Veterinarians IF Fellow-Medical 1R Resident-Medical IS Intern-Dental IT Fellow-Dental 1U Resident-Dental IV Veterinarian 2 Direct Care Professional 2P...concerned with the Physical Therapy clinic under the Orthopedic (ORTHO) primary product line within the ambulatory section of the Product Line

  15. Correlative microscopy of detergent granules.

    Science.gov (United States)

    van Dalen, G; Nootenboom, P; Heussen, P C M

    2011-03-01

    The microstructure of detergent products for textile cleaning determines to a large extent the physical properties of these products. Correlative microscopy was used to reveal the microstructure by reconciling images obtained by scanning electron microscopy with energy dispersive X-ray analysis, X-ray microtomography and Fourier transform infrared microscopy. These techniques were applied on the same location of a subsample of a spray-dried detergent base powder embedded in polyacrylate. In this way, the three-dimensional internal and external structure of detergent granules could be investigated from milli to nano scale with detailed spatial information about the components present. This will generate knowledge how to design optimal microstructures for laundry products to obtain product properties demanded by the market. This method is also very useful for other powder systems used in a large variety of industries (e.g. for pharmaceutical, food, ceramic and metal industries).

  16. Implementation outcomes of evidence-based quality improvement for depression in VA community based outpatient clinics

    Directory of Open Access Journals (Sweden)

    Fortney John

    2012-04-01

    Full Text Available Abstract Background Collaborative-care management is an evidence-based practice for improving depression outcomes in primary care. The Department of Veterans Affairs (VA has mandated the implementation of collaborative-care management in its satellite clinics, known as Community Based Outpatient Clinics (CBOCs. However, the organizational characteristics of CBOCs present added challenges to implementation. The objective of this study was to evaluate the effectiveness of evidence-based quality improvement (EBQI as a strategy to facilitate the adoption of collaborative-care management in CBOCs. Methods This nonrandomized, small-scale, multisite evaluation of EBQI was conducted at three VA Medical Centers and 11 of their affiliated CBOCs. The Plan phase of the EBQI process involved the localized tailoring of the collaborative-care management program to each CBOC. Researchers ensured that the adaptations were evidence based. Clinical and administrative staff were responsible for adapting the collaborative-care management program for local needs, priorities, preferences and resources. Plan-Do-Study-Act cycles were used to refine the program over time. The evaluation was based on the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance Framework and used data from multiple sources: administrative records, web-based decision-support systems, surveys, and key-informant interviews. Results Adoption: 69.0% (58/84 of primary care providers referred patients to the program. Reach: 9.0% (298/3,296 of primary care patients diagnosed with depression who were not already receiving specialty care were enrolled in the program. Fidelity: During baseline care manager encounters, education/activation was provided to 100% (298/298 of patients, barriers were assessed and addressed for 100% (298/298 of patients, and depression severity was monitored for 100% (298/298 of patients. Less than half (42.5%, 681/1603 of follow-up encounters during the acute

  17. Development of the Computerized Model of Performance-Based Measurement System to Measure Nurses' Clinical Competence.

    Science.gov (United States)

    Liou, Shwu-Ru; Liu, Hsiu-Chen; Tsai, Shu-Ling; Cheng, Ching-Yu; Yu, Wei-Chieh; Chu, Tsui-Ping

    2016-04-01

    Critical thinking skills and clinical competence are for providing quality patient care. The purpose of this study is to develop the Computerized Model of Performance-Based Measurement system based on the Clinical Reasoning Model. The system can evaluate and identify learning needs for clinical competency and be used as a learning tool to increase clinical competency by using computers. The system includes 10 high-risk, high-volume clinical case scenarios coupled with questions testing clinical reasoning, interpersonal, and technical skills. Questions were sequenced to reflect patients' changing condition and arranged by following the process of collecting and managing information, diagnosing and differentiating urgency of problems, and solving problems. The content validity and known-groups validity was established. The Kuder-Richardson Formula 20 was 0.90 and test-retest reliability was supported (r = 0.78). Nursing educators can use the system to understand students' needs for achieving clinical competence, and therefore, educational plans can be made to better prepare students and facilitate their smooth transition to a future clinical environment. Clinical nurses can use the system to evaluate their performance-based abilities and weakness in clinical reasoning. Appropriate training programs can be designed and implemented to practically promote nurses' clinical competence and quality of patient care.

  18. Personalized Clinical Diagnosis in Data Bases for Treatment Support in Phthisiology.

    Science.gov (United States)

    Lugovkina, T K; Skornyakov, S N; Golubev, D N; Egorov, E A; Medvinsky, I D

    2016-01-01

    The decision-making is a key event in the clinical practice. The program products with clinical decision support models in electronic data-base as well as with fixed decision moments of the real clinical practice and treatment results are very actual instruments for improving phthisiological practice and may be useful in the severe cases caused by the resistant strains of Mycobacterium tuberculosis. The methodology for gathering and structuring of useful information (critical clinical signals for decisions) is described. Additional coding of clinical diagnosis characteristics was implemented for numeric reflection of the personal situations. The created methodology for systematization and coding Clinical Events allowed to improve the clinical decision models for better clinical results.

  19. Spirulina in clinical practice: evidence-based human applications.

    Science.gov (United States)

    Karkos, P D; Leong, S C; Karkos, C D; Sivaji, N; Assimakopoulos, D A

    2011-01-01

    Spirulina or Arthrospira is a blue-green alga that became famous after it was successfully used by NASA as a dietary supplement for astronauts on space missions. It has the ability to modulate immune functions and exhibits anti-inflammatory properties by inhibiting the release of histamine by mast cells. Multiple studies investigating the efficacy and the potential clinical applications of Spirulina in treating several diseases have been performed and a few randomized controlled trials and systematic reviews suggest that this alga may improve several symptoms and may even have an anticancer, antiviral and antiallergic effects. Current and potential clinical applications, issues of safety, indications, side-effects and levels of evidence are addressed in this review. Areas of ongoing and future research are also discussed.

  20. Spirulina in Clinical Practice: Evidence-Based Human Applications

    Directory of Open Access Journals (Sweden)

    P. D. Karkos

    2011-01-01

    Full Text Available Spirulina or Arthrospira is a blue-green alga that became famous after it was successfully used by NASA as a dietary supplement for astronauts on space missions. It has the ability to modulate immune functions and exhibits anti-inflammatory properties by inhibiting the release of histamine by mast cells. Multiple studies investigating the efficacy and the potential clinical applications of Spirulina in treating several diseases have been performed and a few randomized controlled trials and systematic reviews suggest that this alga may improve several symptoms and may even have an anticancer, antiviral and antiallergic effects. Current and potential clinical applications, issues of safety, indications, side-effects and levels of evidence are addressed in this review. Areas of ongoing and future research are also discussed.

  1. Spirulina in Clinical Practice: Evidence-Based Human Applications

    OpenAIRE

    Karkos, P. D.; Leong, S. C.; C. D. Karkos; Sivaji, N.; Assimakopoulos, D. A.

    2011-01-01

    Spirulina or Arthrospira is a blue-green alga that became famous after it was successfully used by NASA as a dietary supplement for astronauts on space missions. It has the ability to modulate immune functions and exhibits anti-inflammatory properties by inhibiting the release of histamine by mast cells. Multiple studies investigating the efficacy and the potential clinical applications of Spirulina in treating several diseases have been performed and a few randomized controlled trials and sy...

  2. Internet in clinical research based on a pilot experience.

    Science.gov (United States)

    López-Carrero, Carmen; Arriaza, Elena; Bolaños, Elena; Ciudad, Antonio; Municio, Marco; Ramos, José; Hesen, Wout

    2005-04-01

    Computing has become an integral part of many disciplines nowadays, turning it into an evermore necessary working tool. Internet provides a fast and easy way to collect scientific data and is becoming a more and more effective and safe way to transmit data. It is also an efficient means for interaction and information sharing within a work group that provides the necessary flexibility. A pilot project was conducted replacing the traditional hardcopy version of the case report form for an electronic one (e-CRF) and with access to Internet within the Naturalistic Randomized Clinical Trial of the Effectiveness of Olanzapine and Risperidone in the Treatment of Schizophrenia. Carrying out this pilot project has given us the opportunity to determine the advantages electronic data collection (EDC) by Internet has to offer both researchers and sponsors. The results have optimized time management, since it is easier to work in real time; data quality is improved, since intermediates are eliminated, and it facilitates communication amongst the different parties involved in the project. The use of this technology requires updated Internet connections and adequate personal computers, since the possibilities offered by the computer system and high-speed connection are critical in conducting the project. Obviously, this may involve a higher initial investment, but the results have revealed to us that these start-up costs are later offset by lowering personnel costs or by decreasing the number of monitoring visits. On the basis of our experience and that of the participating investigators, certain recommendations for future clinical trials using e-CRF can be made. We will go into these recommendations in greater depth throughout this paper. In short, EDC can dramatically improve the clinical trial process, opening the door to new technologies in the world of clinical research, not only for sponsors, but also for clinicians.

  3. Novel phosphate-based cements for clinical applications

    OpenAIRE

    2012-01-01

    This Thesis aims at the development of two novel families of inorganic phosphate cements with suitable characteristics for clinical applications in hard tissue regeneration or replacement. It is organized in two distinct parts. The first part focuses at the development of silicon-doped a-tricalcium phosphate and the subsequent preparation of a silicon-doped calcium phosphate cement for bone regeneration applications. For this purpose, silicon-doped a-tricalcium phosphate was synthesized b...

  4. X-ray fluorescence microscopy demonstrates preferential accumulation of a vanadium-based magnetic resonance imaging contrast agent in murine colonic tumors.

    Science.gov (United States)

    Mustafi, Devkumar; Ward, Jesse; Dougherty, Urszula; Bissonnette, Marc; Hart, John; Vogt, Stefan; Karczmar, Gregory S

    2015-01-01

    Contrast agents that specifically enhance cancers on magnetic resonance imaging (MRI) will allow earlier detection. Vanadium-based chelates (VCs) selectively enhance rodent cancers on MRI, suggesting selective uptake of VCs by cancers. Here we report x-ray fluorescence microscopy (XFM) of VC uptake by murine colon cancer. Colonic tumors in mice treated with azoxymethane/dextran sulfate sodium were identified by MRI. Then a gadolinium-based contrast agent and a VC were injected intravenously; mice were sacrificed and colons sectioned. VC distribution was sampled at 120 minutes after injection to evaluate the long-term accumulation. Gadolinium distribution was sampled at 10 minutes after injection due to its rapid washout. XFM was performed on 72 regions of normal and cancerous colon from five normal mice and four cancer-bearing mice. XFM showed that all gadolinium was extracellular, with similar concentrations in colon cancers and normal colon. In contrast, the average VC concentration was twofold higher in cancers versus normal tissue (p < .002). Cancers also contained numerous "hot spots" with intracellular VC concentrations sixfold higher than the concentration in normal colon (p < .0001). No hot spots were detected in normal colon. This is the first direct demonstration that VCs selectively accumulate in cancer cells and thus may improve cancer detection.

  5. Enhanced Optoelectronic Performance of a Passivated Nanowire-Based Device: Key Information from Real-Space Imaging Using 4D Electron Microscopy

    KAUST Repository

    Khan, Jafar Iqbal

    2016-03-03

    Managing trap states and understanding their role in ultrafast charge-carrier dynamics, particularly at surface and interfaces, remains a major bottleneck preventing further advancements and commercial exploitation of nanowire (NW)-based devices. A key challenge is to selectively map such ultrafast dynamical processes on the surfaces of NWs, a capability so far out of reach of time-resolved laser techniques. Selective mapping of surface dynamics in real space and time can only be achieved by applying four-dimensional scanning ultrafast electron microscopy (4D S-UEM). Charge carrier dynamics are spatially and temporally visualized on the surface of InGaN NW arrays before and after surface passivation with octadecylthiol (ODT). The time-resolved secondary electron images clearly demonstrate that carrier recombination on the NW surface is significantly slowed down after ODT treatment. This observation is fully supported by enhancement of the performance of the light emitting device. Direct observation of surface dynamics provides a profound understanding of the photophysical mechanisms on materials\\' surfaces and enables the formulation of effective surface trap state management strategies for the next generation of high-performance NW-based optoelectronic devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Automated analysis of siRNA screens of cells infected by hepatitis C and dengue viruses based on immunofluorescence microscopy images

    Science.gov (United States)

    Matula, Petr; Kumar, Anil; Wörz, Ilka; Harder, Nathalie; Erfle, Holger; Bartenschlager, Ralf; Eils, Roland; Rohr, Karl

    2008-03-01

    We present an image analysis approach as part of a high-throughput microscopy siRNA-based screening system using cell arrays for the identification of cellular genes involved in hepatitis C and dengue virus replication. Our approach comprises: cell nucleus segmentation, quantification of virus replication level in the neighborhood of segmented cell nuclei, localization of regions with transfected cells, cell classification by infection status, and quality assessment of an experiment and single images. In particular, we propose a novel approach for the localization of regions of transfected cells within cell array images, which combines model-based circle fitting and grid fitting. By this scheme we integrate information from single cell array images and knowledge from the complete cell arrays. The approach is fully automatic and has been successfully applied to a large number of cell array images from screening experiments. The experimental results show a good agreement with the expected behaviour of positive as well as negative controls and encourage the application to screens from further high-throughput experiments.

  7. Clinical review: Reunification of acid–base physiology

    OpenAIRE

    2005-01-01

    Recent advances in acid–base physiology and in the epidemiology of acid–base disorders have refined our understanding of the basic control mechanisms that determine blood pH in health and disease. These refinements have also brought parity between the newer, quantitative and older, descriptive approaches to acid–base physiology. This review explores how the new and older approaches to acid–base physiology can be reconciled and combined to result in a powerful bedside tool. A case based tutori...

  8. Metadata registry and management system based on ISO 11179 for Cancer Clinical Trials Information System.

    Science.gov (United States)

    Park, Yu Rang; Kim, Ju Han

    2006-01-01

    Standardized management of data elements (DEs) for Case Report Form (CRF) is crucial in Clinical Trials Information System (CTIS). Traditional CTISs utilize organization-specific definitions and storage methods for Des and CRFs. We developed metadata-based DE management system for clinical trials, Clinical and Histopathological Metadata Registry (CHMR), using international standard for metadata registry (ISO 11179) for the management of cancer clinical trials information. CHMR was evaluated in cancer clinical trials with 1625 DEs extracted from the College of American Pathologists Cancer Protocols for 20 major cancers.

  9. Lasers for nonlinear microscopy.

    Science.gov (United States)

    Wise, Frank

    2013-03-01

    Various versions of nonlinear microscopy are revolutionizing the life sciences, almost all of which are made possible because of the development of ultrafast lasers. In this article, the main properties and technical features of short-pulse lasers used in nonlinear microscopy are summarized. Recent research results on fiber lasers that will impact future instruments are also discussed.

  10. LEDs for fluorescence microscopy

    NARCIS (Netherlands)

    Young, I.T.; Garini, Y.; Dietrich, H.R.C.; Van Oel, W.; Liqui Lung, G.

    2004-01-01

    Traditional light sources for fluorescence microscopy have been mercury lamps, xenon lamps, and lasers. These sources have been essential in the development of fluorescence microscopy but each can have serious disadvantages: lack of near monochromaticity, heat generation, cost, lifetime of the light

  11. A history of urine microscopy.

    Science.gov (United States)

    Cameron, J Stewart

    2015-11-01

    The naked-eye appearance of the urine must have been studied by shamans and healers since the Stone Age, and an elaborate interpretation of so-called Uroscopy began around 600 AD as a form of divination. A 1000 years later, the first primitive monocular and compound microscopes appeared in the Netherlands, and along with many other objects and liquids, urine was studied from around 1680 onwards as the enlightenment evolved. However, the crude early instruments did not permit fine study because of chromatic and linear/spherical blurring. Only after complex multi-glass lenses which avoided these problems had been made and used in the 1820s in London by Lister, and in Paris by Chevalier and Amici, could urinary microscopy become a practical, clinically useful tool in the 1830s. Clinical urinary microscopy was pioneered by Rayer and his pupils in Paris (especially Vigla), in the late 1830s, and spread to UK and Germany in the 1840s, with detailed descriptions and interpretations of cells and formed elements of the urinary sediment by Nasse, Henle, Robinson and Golding Bird. Classes were held, most notably by Donné in Paris. After another 50 years, optical microscopy had reached its apogee, with magnifications of over 1000 times obtainable free of aberration, using immersion techniques. Atlases of the urinary sediment were published in all major European countries and in the US. Polarised light and phase contrast was used also after 1900 to study urine, and by the early 20th century, photomicroscopy (pioneered by Donné and Daguerre 50 years previously, but then ignored) became usual for teaching and recording. In the 1940s electron microscopy began, followed by detection of specific proteins and cells using immunofluorescent antibodies. All this had been using handheld methodology. Around 1980, machine-assisted observations began, and have dominated progress since.

  12. Team-based learning, a learning strategy for clinical reasoning, in students with problem-based learning tutorial experiences.

    Science.gov (United States)

    Okubo, Yumiko; Ishiguro, Naoko; Suganuma, Taiyo; Nishikawa, Toshio; Takubo, Toshio; Kojimahara, Noriko; Yago, Rie; Nunoda, Shinichi; Sugihara, Shigetaka; Yoshioka, Toshimasa

    2012-01-01

    Acquiring clinical reasoning skills in lectures may be difficult, but it can be learnt through problem-solving in the context of clinical practice. Problem finding and solving are skills required for clinical reasoning; however, students who underwent problem-based learning (PBL) still have difficulty in acquiring clinical reasoning skills. We hypothesized that team-based learning (TBL), a learning strategy that provides the opportunity to solve problems by repeatedly taking tests, can enhance the clinical reasoning ability in medical students with PBL experiences during the pre-clinical years. TBL courses were designed for 4(th) year students in a 6-year program in 2008, 2009, and 2010. TBL individual scores, consisting of a combination of individual and group tests, were compared with scores of several examinations including computer-based testing (CBT), an original examination assessing clinical reasoning ability (problem-solving ability test; P-SAT), term examinations, and Objective Structured Clinical Examination (OSCE). CBT, OSCE and P-SAT scores were compared with those of students who learned clinical reasoning only through PBL tutorials in 2005, 2006, and 2007 (non-TBL students). Individual TBL scores of students did not correlate with scores of any other examination. Assessments on clinical reasoning ability, such as CBT, OSCE, and P-SAT scores, were significantly higher in TBL students compared with non-TBL students. Students found TBL to be effective, particularly in areas of problem solving by both individuals and teams, and feedback from specialists. In conclusion, TBL for clinical reasoning is useful in improving clinical reasoning ability in students with PBL experiences with limited clinical exposure.

  13. Photothermal Single Particle Microscopy

    CERN Document Server

    Selmke, Markus; Cichos, Frank

    2011-01-01

    Photothermal microscopy has recently complemented single molecule fluorescence microscopy by the detection of individual nano-objects in absorption. Photothermal techniques gain their superior sensitivity by exploiting a heat induced refractive index change around the absorbing nano-object. Numerous new applications to nanoparticles, nanorods and even single molecules have been reported all refering to the fact that photothermal microscopy is an extinction measurement on a heat induced refractive index profile. Here, we show that the actual physical mechanism generating a photothermal signal from a single molecule/particle is fundamentally different from the assumed extinction measurement. Combining photothermal microscopy, light scattering microscopy as well as accurate Mie scattering calculations to single gold nanoparticles, we reveal that the detection mechanism is quantitatively explained by a nanolensing effect of the long range refractive index profile. Our results lay the foundation for future develop...

  14. Online survey system for image-based clinical guideline studies using the Delphi method.

    Science.gov (United States)

    Harper, Todd M; Teng, Chia-Chi

    2011-01-01

    The increasing use of health information technology (HIT) is due to a rising interest in improving the quality of health care. HIT has the potential to reduce cost and transform services. Proper clinical support systems will contribute to the meaningful use of HIT systems by providing a wide array of data to clinicians for the diagnosis and treatments. Clinical guidelines, created by a consensus of experts, can be put in place to assist physicians in making clinical decisions. Delphi methods are commonly used to create consensus from surveys completed by a team of experts. Image based studies could create guidelines that standardize severity, deformity or other clinical classifications. As these studies were traditionally conducted using paper based media, the cost and time requirement often make the process impractical. Ware proposing a web based system to aid medical researchers in conducting image based Delphi studies for improved clinical guidelines and decision support.

  15. Extracting clinical information to support medical decision based on standards.

    Science.gov (United States)

    Gomoi, Valentin; Vida, Mihaela; Stoicu-Tivadar, Lăcrămioara; Stoicu-Tivadar, Vasile

    2011-01-01

    The paper presents a method connecting medical databases to a medical decision system, and describes a service created to extract the necessary information that is transferred based on standards. The medical decision can be improved based on many inputs from different medical locations. The developed solution is described for a concrete case concerning the management for chronic pelvic pain, based on the information retrieved from diverse healthcare databases.

  16. ATTITUDE AND PERCEPTION OF FACULTIES TOWARDS TEACHING EVIDENCE BASED MEDICINE TO PRE - CLINICAL & PARA - CLINICAL MEDICAL STUDENTS

    Directory of Open Access Journals (Sweden)

    Bhavita Patel

    2015-02-01

    Full Text Available NTRODUCTION: Evidence - based medicine (EBM is defined as the „conscientious, explicit, and judicious use of current best evidence‟. It i s an important tool for lifelong learning in medicine, and medical students can develop the skills necessary to understand and use EBM. The teaching of EBM in Sumandeep Vidyapeeth is as part of Evidence Based Education System (EBES. The university has imp lemented the 16 hours of teaching with project work on Evidence Based Medicine in 1st MBBS and 2nd MBBS curriculum in addition to MBBS syllabus. AIMS & OBJECTIVES: This study was planned to take feedback from all the faculties those who are involved in Evi dence based Medicine teaching to evaluate their attitude and perception towards this innovative teaching method and to recommend improvements. MATERIAL & METHODS: A Descriptive, self - structured , pilot pretested questionnaire based cross sectional study was conducted in the year 2013 - 2014 among 40 faculties from 7 Departments like Anatomy, Physiology, Biochemistry, Microbiology, Pharmacology, Pathology and Forensic Medicine teaching Evidence Base d Medicine to students at S.B.K.S MI & RC, Sumandeep Vidyapeeth. Data was expressed as percentage. RESULTS: The response rate for the study was 75%. Almost 87% of faculties agreed that teaching EBM is a welcoming development during pre and para clinical ye ars. About 80% faculties agreed that it will help them in future clinical learning. 87% faculties agreed that literature and research searching improves their day to day teaching. About 77% of faculties have attended workshop and training held in Universit y and 83% of faculties agreed that they are interested in more learning and improving skills necessary to incorporate Evidence based medicine into their discipline. Barriers included shortage of time and need for training in teaching EBM. CONCLUSION: Facul ties of this University teaching Pre - clinical and Para - clinical medical students recognized

  17. A work-based learning approach for clinical support workers on mental health inpatient wards.

    Science.gov (United States)

    Kemp, Philip; Gilding, Moorene; Seewooruttun, Khooseal; Walsh, Hannah

    2016-09-14

    Background With a rise in the number of unqualified staff providing health and social care, and reports raising concerns about the quality of care provided, there is a need to address the learning needs of clinical support workers. This article describes a qualitative evaluation of a service improvement project that involved a work-based learning approach for clinical support workers on mental health inpatient wards. Aim To investigate and identify insights in relation to the content and process of learning using a work-based learning approach for clinical support workers. Method This was a qualitative evaluation of a service improvement project involving 25 clinical support workers at the seven mental health inpatient units in South London and Maudsley NHS Foundation Trust. Three clinical skills tutors were appointed to develop, implement and evaluate the work-based learning approach. Four sources of data were used to evaluate this approach, including reflective journals, qualitative responses to questionnaires, three focus groups involving the clinical support workers and a group interview involving the clinical skills tutors. Data were analysed using thematic analysis. Findings The work-based learning approach was highly valued by the clinical support workers and enhanced learning in practice. Face-to-face learning in practice helped the clinical support workers to develop practice skills and reflective learning skills. Insights relating to the role of clinical support workers were also identified, including the benefits of face-to-face supervision in practice, particularly in relation to the interpersonal aspects of care. Conclusion A work-based learning approach has the potential to enhance care delivery by meeting the learning needs of clinical support workers and enabling them to apply learning to practice. Care providers should consider how the work-based learning approach can be used on a systematic, organisation-wide basis in the context of budgetary

  18. Magnetic force microscopy: Quantitative issues in biomaterials

    NARCIS (Netherlands)

    Passeri, D.; Dong, C.; Reggente, M.; Angeloni, L.; Barteri, M.; Scaramuzzo, F.A.; De Angelis, F.; Marinelli, F.; Antonelli, F.; Rinaldi, F.; Marianecci, C.; Carafa, M.; Sorbo, A.; Sordi, D.; Arends, I.W.C.E.; Rossi, M.

    2014-01-01

    Magnetic force microscopy (MFM) is an atomic force microscopy (AFM) based technique in which an AFM tip with a magnetic coating is used to probe local magnetic fields with the typical AFM spatial resolution, thus allowing one to acquire images reflecting the local magnetic properties of the samples

  19. Robust tumor morphometry in multispectral fluorescence microscopy

    Science.gov (United States)

    Tabesh, Ali; Vengrenyuk, Yevgen; Teverovskiy, Mikhail; Khan, Faisal M.; Sapir, Marina; Powell, Douglas; Mesa-Tejada, Ricardo; Donovan, Michael J.; Fernandez, Gerardo

    2009-02-01

    Morphological and architectural characteristics of primary tissue compartments, such as epithelial nuclei (EN) and cytoplasm, provide important cues for cancer diagnosis, prognosis, and therapeutic response prediction. We propose two feature sets for the robust quantification of these characteristics in multiplex immunofluorescence (IF) microscopy images of prostate biopsy specimens. To enable feature extraction, EN and cytoplasm regions were first segmented from the IF images. Then, feature sets consisting of the characteristics of the minimum spanning tree (MST) connecting the EN and the fractal dimension (FD) of gland boundaries were obtained from the segmented compartments. We demonstrated the utility of the proposed features in prostate cancer recurrence prediction on a multi-institution cohort of 1027 patients. Univariate analysis revealed that both FD and one of the MST features were highly effective for predicting cancer recurrence (p <= 0.0001). In multivariate analysis, an MST feature was selected for a model incorporating clinical and image features. The model achieved a concordance index (CI) of 0.73 on the validation set, which was significantly higher than the CI of 0.69 for the standard multivariate model based solely on clinical features currently used in clinical practice (p < 0.0001). The contributions of this work are twofold. First, it is the first demonstration of the utility of the proposed features in morphometric analysis of IF images. Second, this is the largest scale study of the efficacy and robustness of the proposed features in prostate cancer prognosis.

  20. Genome-based versus gene-based theory of cancer: Possible implications for clinical practice

    Indian Academy of Sciences (India)

    Nataša Todorović-Raković

    2011-09-01

    The current state in oncology research indicates that the attempts to explain such complex process as cancerogenesis by a single or several genetic mutations were not successful enough. On the other hand, chromosomal/genomic instability – almost universal features of malignant tumours which influence a global pattern of gene expression and, subsequently, many oncogenic pathways – were often disregarded and considered nonessential to clinical application. However, a new arising field of system biology including ‘new forms’ of genome diversity such as copy number variations (CNV) and high-throughput oncogene mutation profiling now reveal all the complexity of cancer and provide the final explanation of the oncogenic pathways, based on stochastic (onco)genomic variation rather than on (onco)genic concepts.

  1. Analytical electron microscopy of W-core β-SiC fibers for use in an SiC-based composite material for fusion applications.

    Science.gov (United States)

    Toplišek, Tea; Gec, Medeja; Iveković, Aljaž; Novak, Saša; Kobe, Spomenka; Dražić, Goran

    2013-08-01

    In this work, the interactions between tungsten (W) and silicon carbide (SiC) in Sigma SiC fibers at high temperatures were characterized using scanning and transmission electron microscopy. These fibers could have the potential for use in fusion-related applications owing to their high thermal conductivity compared with pure SiC-based fibers. The as-received fibers were composed of a 100-μm-thick shell of radially textured β-SiC grains and a 15-μm-thick tungsten core, composed of a few hundreds of nm-sized elongated tungsten grains. The interfaces between the tungsten and the SiC and the SiC and the outer coatings were sharp and smooth. After heat treatment at 1,600°C for 3 h in Ar, the tungsten core reacted with SiC to form a rough interface surface. Inside the core, W₅Si₃, W₃Si, and W₂C phases were detected using energy-dispersive X-ray spectroscopy and electron-diffraction techniques. The mechanical properties of the fibers deteriorate after the heat treatment.

  2. Object-wave reconstruction by carbon film-based Zernike- and Hilbert-phase plate microscopy: A theoretical study not restricted to weak-phase objects

    Energy Technology Data Exchange (ETDEWEB)

    Dries, M., E-mail: manuel.dries@kit.edu [Laboratorium fuer Elektronenmikroskopie, Karlsruher Institut fuer Technologie (KIT), D-76128 Karlsruhe (Germany); Schultheiss, K.; Gamm, B. [Laboratorium fuer Elektronenmikroskopie, Karlsruher Institut fuer Technologie (KIT), D-76128 Karlsruhe (Germany); Rosenauer, A. [Institut fuer Festkoerperphysik, Universitaet Bremen, D-28359 Bremen (Germany); Schroeder, R.R. [BioQuant CellNetworks, Universitaet Heidelberg, D-69120 Heidelberg (Germany); Gerthsen, D. [Laboratorium fuer Elektronenmikroskopie, Karlsruher Institut fuer Technologie (KIT), D-76128 Karlsruhe (Germany)

    2011-01-15

    Transmission electron microscopy phase-contrast images taken by amorphous carbon film-based phase plates are affected by the scattering of electrons within the carbon film causing a modification of the image-wave function. Moreover, image artefacts are produced by non-centrosymmetric phase plate designs such as the Hilbert-phase plate. Various methods are presented to correct phase-contrast images with respect to the scattering of electrons and image artefacts induced by phase plates. The proposed techniques are not restricted to weak-phase objects and linear image formation. Phase-contrast images corrected by the presented methods correspond to those taken by an ideal centrosymmetric, matter-free phase plate and are suitable for object-wave reconstruction. -- Research Highlights: {yields} Object-wave reconstruction by phase plates considering nonlinear image formation. {yields} Requirement of three (five) images in case of Zernike- (Hilbert-) phase plates. {yields} Analytical correction of damping and/or image artefacts induced by phase plates.{yields} Validation by simulation of crystalline silicon.

  3. Scanning transmission X-ray microscopy probe for in situ mechanism study of graphene-oxide-based resistive random access memory.

    Science.gov (United States)

    Nho, Hyun Woo; Kim, Jong Yun; Wang, Jian; Shin, Hyun-Joon; Choi, Sung-Yool; Yoon, Tae Hyun

    2014-01-01

    Here, an in situ probe for scanning transmission X-ray microscopy (STXM) has been developed and applied to the study of the bipolar resistive switching (BRS) mechanism in an Al/graphene oxide (GO)/Al resistive random access memory (RRAM) device. To perform in situ STXM studies at the C K- and O K-edges, both the RRAM junctions and the I0 junction were fabricated on a single Si3N4 membrane to obtain local XANES spectra at these absorption edges with more delicate I0 normalization. Using this probe combined with the synchrotron-based STXM technique, it was possible to observe unique chemical changes involved in the BRS process of the Al/GO/Al RRAM device. Reversible oxidation and reduction of GO induced by the externally applied bias voltages were observed at the O K-edge XANES feature located at 538.2 eV, which strongly supported the oxygen ion drift model that was recently proposed from ex situ transmission electron microscope studies.

  4. Insights into electrode/electrolyte interfacial processes and the effect of nanostructured cobalt oxides loading on graphene-based hybrids by scanning electrochemical microscopy

    Science.gov (United States)

    Gupta, Sanju; Carrizosa, Sara B.

    2016-12-01

    Nanostructured cobalt oxide polymorphs (CoO and Co3O4) deposited via electrodeposition allowed optimal loading on supercapacitive graphene nanosheets producing a set of graphene-based hybrids namely, CoO/GO, CoO/ErGO, Co3O4/GO, Co3O4/rGO, and Co3O4/ErGO, as pseudocapacitive electrochemical electrodes. We gained fundamental insights into the complex physicochemical interfacial processes at electrode surfaces and electrode/electrolyte (or solid/liquid) interfaces by scanning electrochemical microscopy operating in the feedback probe approach and imaging modes while monitoring and mapping the redox probe (re)activity behavior. We determined the various experimental descriptors including diffusion coefficient, electron transfer rate, and electroactive site distribution on electrodes. We emphasize the interplay of (1) heterogeneous basal and edge plane active sites, (2) graphene surface functional moieties (conducting/semiconducting), and (3) crystalline spinel cobalt oxides (semiconducting/insulating) coated graphene, reinforcing the available electron density of states in the vicinity of the Fermi level contributing to higher electroactivity, faster interfacial diffusion, and shorter distances for electron transfer, facilitated through molecular and chemical bridges obtained by electrodeposition as compared with the physical deposition.

  5. Evidence Base of Clinical Studies on Tai Chi: A Bibliometric Analysis

    OpenAIRE

    Guo-Yan Yang; Li-Qiong Wang; Jun Ren; Yan Zhang; Meng-Ling Li; Yu-Ting Zhu; Jing Luo; Yan-Jun Cheng; Wen-Yuan Li; Peter M. Wayne; Jian-Ping Liu

    2015-01-01

    BACKGROUND: The safety and health benefits of Tai Chi mind-body exercise has been documented in a large number of clinical studies focused on specific diseases and health conditions. The objective of this systematic review is to more comprehensively summarize the evidence base of clinical studies of Tai Chi for healthcare. METHODS AND FINDINGS: We searched for all types of clinical studies on Tai chi in PubMed, the Cochrane Library and four major Chinese electronic databases from their incept...

  6. Multiphoton microscopy based cryo-imaging of inflated frozen human lung sections at -60°C in healthy and COPD lungs

    Science.gov (United States)

    Abraham, Thomas; Kayra, Damian; Zhang, Angela; Suzuki, Masaru; McDonough, John; Elliott, W. M.; Cooper, Joel D.; Hogg, James C.

    2013-02-01

    Lung is a complex gas exchanger with interfacial area (where the gas exchange takes place) is about the size of a tennis court. Respiratory function is linked to the biomechanical stability of the gas exchange or alveolar regions which directly depends on the spatial distributions of the extracellular matrix fibers such fibrillar collagens and elastin fibers. It is very important to visualize and quantify these fibers at their native and inflated conditions to have correct morphometric information on differences between control and diseased states. This can be only achieved in the ex vivo states by imaging directly frozen lung specimens inflated to total lung capacity. Multiphoton microscopy, which uses ultra-short infrared laser pulses as the excitation source, produces multiphoton excitation fluorescence (MPEF) signals from endogenously fluorescent proteins (e.g. elastin) and induces specific second harmonic generation (SHG) signals from non-centrosymmetric proteins such as fibrillar collagens in fresh human lung tissues [J. Struct. Biol. (2010)171,189-196]. Here we report for the first time 3D image data obtained directly from thick frozen inflated lung specimens (~0.7- 1.0 millimeter thick) visualized at -60°C without prior fixation or staining in healthy and diseased states. Lung specimens donated for transplantation and released for research when no appropriate recipient was identified served as controls, and diseased lung specimens donated for research by patients receiving lung transplantation for very severe COPD (n=4) were prepared as previously described [N. Engl. J. Med. (2011) 201, 1567]. Lung slices evenly spaced between apex and base were examined using multiphoton microscopy while maintained at -60°C using a temperature controlled cold stage with a temperature resolution of 0.1°C. Infrared femto-second laser pulses tuned to 880nm, dry microscopic objectives, and non-de-scanned detectors/spectrophotometer located in the reflection geometry were

  7. Diagnostic electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Dickersin, G.R.

    1988-01-01

    In this book the author presents a comprehensive reference text on diagnostic electron microscopy. Throughout the book he illustrates how ultrastructural identification can be helpful for the recognition of cell type and the identification of mechanisms of pathogenesis in various diseases. In addition to electron microscopy photographs, there are also numerous light microscopy photographs for comparison. This text presents the classification of neoplasms in the order and arrangement most familiar to the pathologist. Contents: Introduction; Diagram of a Normal Cell; Normal Cell Function; Embryology; Neoplasms; Infectious Agents; Metabolic Diseases; Renal Diseases; Skeletal Muscle and Peripheral Nerve Diseases; Index.

  8. Intraspecies Transmission of BASE Induces Clinical Dullness and Amyotrophic Changes

    Science.gov (United States)

    Lombardi, Guerino; Casalone, Cristina; D' Angelo, Antonio; Gelmetti, Daniela; Torcoli, Gloria; Barbieri, Ilaria; Corona, Cristiano; Fasoli, Elisa; Farinazzo, Alessia; Fiorini, Michele; Gelati, Matteo; Iulini, Barbara; Tagliavini, Fabrizio; Ferrari, Sergio; Caramelli, Maria; Monaco, Salvatore; Capucci, Lorenzo; Zanusso, Gianluigi

    2008-01-01

    The disease phenotype of bovine spongiform encephalopathy (BSE) and the molecular/ biological properties of its prion strain, including the host range and the characteristics of BSE-related disorders, have been extensively studied since its discovery in 1986. In recent years, systematic testing of the brains of cattle coming to slaughter resulted in the identification of at least two atypical forms of BSE. These emerging disorders are characterized by novel conformers of the bovine pathological prion protein (PrPTSE), named high-type (BSE-H) and low-type (BSE-L). We recently reported two Italian atypical cases with a PrPTSE type identical to BSE-L, pathologically characterized by PrP amyloid plaques and known as bovine amyloidotic spongiform encephalopathy (BASE). Several lines of evidence suggest that BASE is highly virulent and easily transmissible to a wide host range. Experimental transmission to transgenic mice overexpressing bovine PrP (Tgbov XV) suggested that BASE is caused by a prion strain distinct from the BSE isolate. In the present study, we experimentally infected Friesian and Alpine brown cattle with Italian BSE and BASE isolates via the intracerebral route. BASE-infected cattle developed amyotrophic changes accompanied by mental dullness. The molecular and neuropathological profiles, including PrP deposition pattern, closely matched those observed in the original cases. This study provides clear evidence of BASE as a distinct prion isolate and discloses a novel disease phenotype in cattle. PMID:18497860

  9. Intraspecies transmission of BASE induces clinical dullness and amyotrophic changes.

    Directory of Open Access Journals (Sweden)

    Guerino Lombardi

    2008-05-01

    Full Text Available The disease phenotype of bovine spongiform encephalopathy (BSE and the molecular/ biological properties of its prion strain, including the host range and the characteristics of BSE-related disorders, have been extensively studied since its discovery in 1986. In recent years, systematic testing of the brains of cattle coming to slaughter resulted in the identification of at least two atypical forms of BSE. These emerging disorders are characterized by novel conformers of the bovine pathological prion protein (PrP(TSE, named high-type (BSE-H and low-type (BSE-L. We recently reported two Italian atypical cases with a PrP(TSE type identical to BSE-L, pathologically characterized by PrP amyloid plaques and known as bovine amyloidotic spongiform encephalopathy (BASE. Several lines of evidence suggest that BASE is highly virulent and easily transmissible to a wide host range. Experimental transmission to transgenic mice overexpressing bovine PrP (Tgbov XV suggested that BASE is caused by a prion strain distinct from the BSE isolate. In the present study, we experimentally infected Friesian and Alpine brown cattle with Italian BSE and BASE isolates via the intracerebral route. BASE-infected cattle developed amyotrophic changes accompanied by mental dullness. The molecular and neuropathological profiles, including PrP deposition pattern, closely matched those observed in the original cases. This study provides clear evidence of BASE as a distinct prion isolate and discloses a novel disease phenotype in cattle.

  10. Intraspecies transmission of BASE induces clinical dullness and amyotrophic changes.

    Science.gov (United States)

    Lombardi, Guerino; Casalone, Cristina; D' Angelo, Antonio; Gelmetti, Daniela; Torcoli, Gloria; Barbieri, Ilaria; Corona, Cristiano; Fasoli, Elisa; Farinazzo, Alessia; Fiorini, Michele; Gelati, Matteo; Iulini, Barbara; Tagliavini, Fabrizio; Ferrari, Sergio; Caramelli, Maria; Monaco, Salvatore; Capucci, Lorenzo; Zanusso, Gianluigi

    2008-05-23

    The disease phenotype of bovine spongiform encephalopathy (BSE) and the molecular/ biological properties of its prion strain, including the host range and the characteristics of BSE-related disorders, have been extensively studied since its discovery in 1986. In recent years, systematic testing of the brains of cattle coming to slaughter resulted in the identification of at least two atypical forms of BSE. These emerging disorders are characterized by novel conformers of the bovine pathological prion protein (PrP(TSE)), named high-type (BSE-H) and low-type (BSE-L). We recently reported two Italian atypical cases with a PrP(TSE) type identical to BSE-L, pathologically characterized by PrP amyloid plaques and known as bovine amyloidotic spongiform encephalopathy (BASE). Several lines of evidence suggest that BASE is highly virulent and easily transmissible to a wide host range. Experimental transmission to transgenic mice overexpressing bovine PrP (Tgbov XV) suggested that BASE is caused by a prion strain distinct from the BSE isolate. In the present study, we experimentally infected Friesian and Alpine brown cattle with Italian BSE and BASE isolates via the intracerebral route. BASE-infected cattle developed amyotrophic changes accompanied by mental dullness. The molecular and neuropathological profiles, including PrP deposition pattern, closely matched those observed in the original cases. This study provides clear evidence of BASE as a distinct prion isolate and discloses a novel disease phenotype in cattle.

  11. Surface Plasmon Resonance for Cell-Based Clinical Diagnosis

    Directory of Open Access Journals (Sweden)

    Yuhki Yanase

    2014-03-01

    Full Text Available Non-invasive real-time observations and the evaluation of living cell conditions and functions are increasingly demanded in life sciences. Surface plasmon resonance (SPR sensors detect the refractive index (RI changes on the surface of sensor chips in label-free and on a real-time basis. Using SPR sensors, we and other groups have developed techniques to evaluate living cells’ reactions in response to stimuli without any labeling in a real-time manner. The SPR imaging (SPRI system for living cells may visualize single cell reactions and has the potential to expand application of SPR cell sensing for clinical diagnosis, such as multi-array cell diagnostic systems and detection of malignant cells among normal cells in combination with rapid cell isolation techniques.

  12. Ultrafast scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Botkin, D.A. [California Univ., Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley Lab., CA (United States)

    1995-09-01

    I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM`s atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

  13. Towards evidence-based clinical practice: an international survey of 18 clinical guideline programs.

    NARCIS (Netherlands)

    Burgers, J.S.; Grol, R.P.T.M.; Klazinga, N.S.; Makela, M.; Zaat, J.O.M.

    2003-01-01

    OBJECTIVE: To describe systematically the structures and working methods of guideline programs. DESIGN: Descriptive survey using a questionnaire with 32 items based on a framework derived from the literature. Answers were tabulated and checked by participants. STUDY PARTICIPANTS: Key informants of 1

  14. Computer-Based versus High-Fidelity Mannequin Simulation in Developing Clinical Judgment in Nursing Education

    Science.gov (United States)

    Howard, Beverly J.

    2013-01-01

    The purpose of this study was to determine if students learn clinical judgment as effectively using computer-based simulations as when using high-fidelity mannequin simulations. There was a single research questions for this study: What is the difference in clinical judgment between participants completing high-fidelity human simulator mannequin…

  15. Change in stated clinical practice associated with participation in the Dental Practice-Based Research Network

    DEFF Research Database (Denmark)

    Gilbert, Gregg H; Richman, Joshua S; Qvist, Vibeke

    2010-01-01

    Clinical researchers have attempted many methods to translate scientific evidence into routine clinical practice, with varying success. Practice-based research networks (PBRNs) provide an important, practitioner-friendly venue to test these methods. Dentist practitioner-investigators from the Den...

  16. Effects of an Art-Based Curriculum on Clinical Trials Attitudes and Breast Cancer Prevention Knowledge

    Science.gov (United States)

    Herman, Patricia M.; Larkey, Linda K.

    2006-01-01

    Although Latinos now comprise the largest minority in the U.S. population, they continue to be seriously underrepresented in clinical trials. A nonrandomized controlled study of an innovative community-developed clinical trial and breast cancer education program targeting Latinas tested whether use of an art-based curriculum could increase…

  17. Students' Experiences of Clinic-Based Learning during a Final Year Veterinary Internship Programme

    Science.gov (United States)

    Matthew, Susan M.; Taylor, Rosanne M.; Ellis, Robert A.

    2010-01-01

    This study investigated veterinary students' experiences of clinic-based learning (CBL) during a comprehensive final year internship programme. Open-ended surveys (n = 93) were used to gather qualitative data about students' conceptions of what is learned during CBL and their approaches to learning in clinics. Phenomenography was used for detailed…

  18. The observation of clinical application of confocal microscopy in the diagnosis and treatment of fungal keratitis%共聚焦显微镜在真菌性角膜炎诊治中应用观察

    Institute of Scientific and Technical Information of China (English)

    郝兆芹; 宋金鑫; 吴洁

    2013-01-01

    after anti-fungus therapy,pathogenetic condition improved at 2-3th week,and the infection was controlled at the 4th week,and then conjunctival flap covering or amniotic membrane grafting could be chosen to promote cornea recovery at this time.Conclusions Confocal microscopy examination is non-invasive and secure,with strong repeatability and short time,can be used to monitor the states and changes of comeal,can be used to conduct clinical therapy and improve the cure rate.

  19. [History of microscopy in Spain].

    Science.gov (United States)

    Fernández-Galiano, D

    1994-12-01

    Nowadays, many Spanish research centers have excellent electronic microscopy services. The current situation, however, should not allow us to forget that the initial steps of microscopy in Spain were very difficult. The construction of excellent optical microscopies in the late XIX century, and their almost immediate introduction in Spain, coincides with a period of thriving scientific activity in our country. Both micrography and histology saw the highlights of their development in Spain, with scientists such as Ramón y Cajal, Río Hortega, Ferrán, Simarro, among others, all of them widely known at present. This article evokes briefly the vicissitudes of Spanish microscopy, from its very beginning in 1843, when the Allgemeine Anatomie by Jacob Henle was translated into Spanish, to present. Scientific historical facts in this article are often accompanied with anecdotes, which show the human aspect of those great scientists. The persevering task carried out by researchers whose names have been recorded in the history of Spanish science and technology, have established the grounds in which our current development is based.

  20. International Multidisciplinary Microscopy Congress

    CERN Document Server

    Oral, Ahmet; Ozer, Mehmet; InterM; INTERM2013

    2014-01-01

    The International Multidisciplinary Microscopy Congress (INTERM2013) was organized on October 10-13, 2013. The aim of the congress was to bring together scientists from various branches to discuss the latest advances in the field of microscopy. The contents of the congress have been broadened to a more "interdisciplinary" scope, so as to allow all scientists working on related subjects to participate and present their work. These proceedings include 39 peer-reviewed technical papers, submitted by leading academic and research institutions from over 12 countries and representing some of the most cutting-edge research available. The 39 papers are grouped into the following sections: - Applications of Microscopy in the Physical Sciences - Applications of Microscopy in the Biological Sciences

  1. Comparison of reflectance confocal microscopy and two-photon second harmonic generation microscopy in fungal keratitis rabbit model ex vivo

    Science.gov (United States)

    Lee, Jun Ho; Lee, Seunghun; Yoon, Calvin J.; Park, Jin Hyoung; Tchah, Hungwon; Kim, Myoung Joon; Kim, Ki Hean

    2016-01-01

    Fungal keratitis is an infection of the cornea by fungal pathogens. Diagnosis methods based on optical microscopy could be beneficial over the conventional microbiology method by allowing rapid and non-invasive examination. Reflectance confocal microscopy (RCM) and two-photon second harmonic generation microscopy (TPSHGM) have been applied to pre-clinical or clinical studies of fungal keratitis. In this report, RCM and TPSHGM were characterized and compared in the imaging of a fungal keratitis rabbit model ex vivo. Fungal infection was induced by using two strains of fungi: aspergillus fumigatus and candida albicans. The infected corneas were imaged in fresh condition by both modalities sequentially and their images were analyzed. Both RCM and TPSHGM could detect both fungal strains within the cornea based on morphology: aspergillus fumigatus had distinctive filamentous structures, and candida albicans had round structures superficially and elongated structures in the corneal stroma. These imaging results were confirmed by histology. Comparison between RCM and TPSHGM showed several characteristics. Although RCM and TPSHGM images had good correlation each other, their images were slightly different due to difference in contrast mechanism. RCM had relatively low image contrast with the infected turbid corneas due to high background signal. TPSHGM visualized cells and collagen in the cornea clearly compared to RCM, but used higher laser power to compensate low autofluorescence. Since these two modalities provide complementary information, combination of RCM and TPSHGM would be useful for fungal keratitis detection by compensating their weaknesses each other. PMID:26977371

  2. Evidence-based diagnosis and clinical decision making

    NARCIS (Netherlands)

    Mileman, P.A.; van den Hout, W.B.

    2009-01-01

    The application of evidence-based dentistry to diagnosis should result in a reduction of errors in decision making. The frequency of errors is dependent not only on the accuracy of a diagnostic test for pathology, but also on the prior chance of disease being present. If this chance is low and below

  3. From Paper Based Clinical Practice Guidelines to Declarative Workflow Management

    DEFF Research Database (Denmark)

    Lyng, Karen Marie; Hildebrandt, Thomas; Mukkamala, Raghava Rao

    2009-01-01

    a sub workflow can be described in a declarative workflow management system: the Resultmaker Online Consultant (ROC). The example demonstrates that declarative primitives allow to naturally extend the paper based flowchart to an executable model without introducing a complex cyclic control flow graph....

  4. Effects of conventional and problem-based learning on clinical and general competencies and career development

    NARCIS (Netherlands)

    Cohen-Schotanus, Janke; Muijtjens, Arno M. M.; Schonrock-Adema, Johanna; Geertsma, Jelle; van der Vleuten, Cees P. M.

    2008-01-01

    OBJECTIVE: To test hypotheses regarding the longitudinal effects of problem-based learning (PBL) and conventional learning relating to students' appreciation of the curriculum, self-assessment of general competencies, summative assessment of clinical competence and indicators of career development.

  5. Developing computational model-based diagnostics to analyse clinical chemistry data

    NARCIS (Netherlands)

    Schalkwijk, D.B. van; Bochove, K. van; Ommen, B. van; Freidig, A.P.; Someren, E.P. van; Greef, J. van der; Graaf, A.A. de

    2010-01-01

    This article provides methodological and technical considerations to researchers starting to develop computational model-based diagnostics using clinical chemistry data.These models are of increasing importance, since novel metabolomics and proteomics measuring technologies are able to produce large

  6. Ontology-based data integration between clinical and research systems.

    Directory of Open Access Journals (Sweden)

    Sebastian Mate

    Full Text Available Data from the electronic medical record comprise numerous structured but uncoded elements, which are not linked to standard terminologies. Reuse of such data for secondary research purposes has gained in importance recently. However, the identification of relevant data elements and the creation of database jobs for extraction, transformation and loading (ETL are challenging: With current methods such as data warehousing, it is not feasible to efficiently maintain and reuse semantically complex data extraction and trans-formation routines. We present an ontology-supported approach to overcome this challenge by making use of abstraction: Instead of defining ETL procedures at the database level, we use ontologies to organize and describe the medical concepts of both the source system and the target system. Instead of using unique, specifically developed SQL statements or ETL jobs, we define declarative transformation rules within ontologies and illustrate how these constructs can then be used to automatically generate SQL code to perform the desired ETL procedures. This demonstrates how a suitable level of abstraction may not only aid the interpretation of clinical data, but can also foster the reutilization of methods for un-locking it.

  7. Sustained effect of simulation-based ultrasound training on clinical performance

    DEFF Research Database (Denmark)

    Tolsgaard, Martin; Ringsted, C; Dreisler, E;

    2015-01-01

    was performed using a virtual-reality TVS simulator until an expert performance level was attained, and was followed by training on a pelvic mannequin. After 2 months of clinical training, one TVS examination was recorded for assessment of each resident's clinical performance (n = 26). Two ultrasound experts......OBJECTIVE: To study the effect of initial simulation-based transvaginal sonography (TVS) training compared with clinical training only, on the clinical performance of residents in obstetrics and gynecology (Ob-Gyn), assessed 2 months into their residency. METHODS: In a randomized study, new Ob...

  8. Mass spectrometry-based proteomics and analyses of serum: a primer for the clinical investigator.

    Science.gov (United States)

    Fusaro, V A; Stone, J H

    2003-01-01

    The vocabulary of proteomics and the swiftly-developing, technological nature of the field constitute substantial barriers to clinical investigators. In recent years, mass spectrometry has emerged as the most promising technique in this field. The purpose of this review is to introduce the field of mass spectrometry-based proteomics to clinical investigators, to explain many of the relevant terms, to introduce the equipment employed in this field, and to outline approaches to asking clinical questions using a proteomic approach. Examples of clinical applications of proteomic techniques are provided from the fields of cancer and vasculitis research, with an emphasis on a pattern recognition approach.

  9. Clinical performance of a light-cured denture base material compared to polymethylmethacrylate--a randomized clinical study.

    Science.gov (United States)

    Gohlke-Wehrße, Hanna-Lena; Giese-Kraft, Katja; Wöstmann, Bernd

    2012-06-01

    The aim of this study was to evaluate the clinical long-term performance of a visible light-cured resin (VLCR) denture base material and to compare it to a well-established polymethylmethacrylate (PMMA)-based denture acrylic in a randomized split-mouth clinical long-term study. One hundred removable partial dentures in 90 patients, with at least two saddles each, were investigated. One saddle was made of VLCR, while the other was made of PMMA at random. Plaque adhesion, tissue reaction, and technical parameters of the dentures were assessed 6, 12, and 18 months after treatment. Statistical analysis was performed using the Wilcoxon rank-sum test. Though VLCR showed higher plaque adhesion than PMMA after 6, 12, and 18 months (p denture acrylic and metal and the boundary between denture acrylic and denture tooth PMMA was rated higher than VLCR. The surface quality of the upper side of the denture saddles showed no significant differences (p > 0.05). Neither VLCR nor PMMA showed discoloration at any point in time (p > 0.05). It can be concluded that VLCR is a viable alternative for the production of removable dentures. Especially in patients with hypersensitivities to PMMA, VLCR is particularly suitable for clinical use.

  10. Community vs. Clinic-Based Modular Treatment of Children with Early-Onset ODD or CD: A Clinical Trial with 3-Year Follow-Up

    Science.gov (United States)

    Kolko, David J.; Dorn, Lorah D.; Bukstein, Oscar G.; Pardini, Dustin; Holden, Elizabeth A.; Hart, Jonathan

    2009-01-01

    This study examines the treatment outcomes of 139, 6-11 year-old, clinically referred boys and girls diagnosed with Oppositional Defiant Disorder (ODD) or Conduct Disorder (CD) who were randomly assigned to a modular-based treatment protocol that was applied by research study clinicians either in the community (COMM) or a clinic office (CLINIC).…

  11. Six school-based clinics: their reproductive health services and impact on sexual behavior.

    Science.gov (United States)

    Kirby, D; Waszak, C; Ziegler, J

    1991-01-01

    An evaluation of the reproductive health programs of six diverse school-based clinics measured the impact of the clinics on sexual behavior and contraceptive use. All six clinics served low-income populations; at five of them, the great majority of the students served were black. An analysis of student visits by type of care given found that these clinics were not primarily family planning facilities; rather, they provided reproductive health care as one component of a comprehensive health program. Student survey data collected in the clinic schools and nearby comparison schools (four sites) or collected both before the clinic opened and two years later (two sites) indicated that the clinics neither hastened the onset of sexual activity nor increased its frequency. The clinics had varying effects on contraceptive use. Providing contraceptives on site was not enough to significantly increase their use; in only one of the three sites that did so were students in the clinic school significantly more likely than students in the comparison school to have used birth control during last intercourse. However, condom use rose sharply at one clinic school that had a strong AIDS education program and was located in a community where AIDS was a salient issue. At another clinic school, where pregnancy prevention was a high priority and staff issued vouchers for contraceptives, the use of condoms and pills was significantly higher than in the comparison school. A third clinic school--which focused on high-risk youth, emphasized pregnancy prevention and dispensed birth control pills--recorded a significantly higher use of pills than its comparison school. Although the data suggest that the clinics probably prevented small numbers of pregnancies at some schools, none of the clinics had a statistically significant effect on school-wide pregnancy rates.

  12. Acute care clinical pharmacy practice: unit- versus service-based models.

    Science.gov (United States)

    Haas, Curtis E; Eckel, Stephen; Arif, Sally; Beringer, Paul M; Blake, Elizabeth W; Lardieri, Allison B; Lobo, Bob L; Mercer, Jessica M; Moye, Pamela; Orlando, Patricia L; Wargo, Kurt

    2012-02-01

    This commentary from the 2010 Task Force on Acute Care Practice Model of the American College of Clinical Pharmacy was developed to compare and contrast the "unit-based" and "service-based" orientation of the clinical pharmacist within an acute care pharmacy practice model and to offer an informed opinion concerning which should be preferred. The clinical pharmacy practice model must facilitate patient-centered care and therefore must position the pharmacist to be an active member of the interprofessional team focused on providing high-quality pharmaceutical care to the patient. Although both models may have advantages and disadvantages, the most important distinction pertains to the patient care role of the clinical pharmacist. The unit-based pharmacist is often in a position of reacting to an established order or decision and frequently is focused on task-oriented clinical services. By definition, the service-based clinical pharmacist functions as a member of the interprofessional team. As a team member, the pharmacist proactively contributes to the decision-making process and the development of patient-centered care plans. The service-based orientation of the pharmacist is consistent with both the practice vision embraced by ACCP and its definition of clinical pharmacy. The task force strongly recommends that institutions pursue a service-based pharmacy practice model to optimally deploy their clinical pharmacists. Those who elect to adopt this recommendation will face challenges in overcoming several resource, technologic, regulatory, and accreditation barriers. However, such challenges must be confronted if clinical pharmacists are to contribute fully to achieving optimal patient outcomes.

  13. [Asymptomatic skull base metastases: clinical course and therapeutic alternatives].

    Science.gov (United States)

    Vargas, A; Paulazo, C; Oleaga, L; Verger, E

    2017-03-01

    Introduccion. Las metastasis sintomaticas de la base craneal (MBC) son una progresion infrecuente, tardia y de mal pronostico en pacientes con tumores solidos. Sus manifestaciones clinicas pueden agruparse en cinco sindromes caracteristicos, y su tratamiento mas frecuente es la radioterapia. Gracias a los progresos tecnologicos en las pruebas de imagen y al seguimiento estrecho de los pacientes con cancer, las MBC pueden diagnosticarse incidentalmente. En este subgrupo no se conoce la evolucion clinica ni se ha establecido la mejor modalidad de tratamiento. Objetivo. Analizar las caracteristicas clinicas y la evolucion de los pacientes diagnosticados incidentalmente de MBC. Pacientes y metodos. Entre enero de 2012 y diciembre de 2015, 31 pacientes con una neoplasia solida diagnosticados de MBC fueron valorados por nuestro servicio. Resultados. Las MBC se diagnosticaron por la presencia de un sindrome de base craneal (n = 24) o incidentalmente (n = 7). Los pacientes sintomaticos fueron tratados con radioterapia. Todos los pacientes diagnosticados incidentalmente permanecieron sin sintomas relacionados con la afectacion de la base craneal hasta la fecha del fallecimiento, aunque frecuentemente presentaron de forma concomitante otros tipos de progresion intracraneal de mal pronostico. Se observo una diferencia estadisticamente significativa en la supervivencia a favor de los pacientes sintomaticos (p = 0,001). Conclusiones. Las MBC diagnosticadas incidentalmente se asociaron frecuentemente a otros tipos de progresion intracraneal, limitando las opciones terapeuticas.

  14. Profile of a unique community-based clinical pharmacy family practice program.

    Science.gov (United States)

    Leff, R D; Helling, D K; Smith, F W; Probasco, R W; Pfeiffer, F G

    1981-01-01

    The provision of clinical pharmaceutical services in family practice offices has aroused considerable national interest among both pharmacists and physicians. Many of these clinical pharmaceutical services and educational programs have been university-funded and/or rely on colleges of pharmacy for fiscal support. Few examples of community-funded, ambulatory care clinical pharmaceutical programs have been reported. Community Health Care, Inc., and Davenport Medical Education Foundation, Inc., are two health care programs which sponsor an innovative ambulatory care clinical pharmacy program. Community Health Care is a nonprofit corporation which utilizes a multidisciplinary team concept to provide comprehensive ambulatory care services to patients. Davenport Medical Education Foundation is a nonprofit corporation that provides a community-based family practice residency program. Because the two separate parent organizations have distinct goals requiring individualized clinical pharmaceutical services, the responsibilities of the clinical pharmacist have evolved to be comprehensive in scope.

  15. Evidence-based clinical practice guidelines for bladder cancer (summary - JUA 2009 Edition).

    Science.gov (United States)

    2010-02-01

    In Japan, until now, the treatment of bladder cancer has been based on guidelines from overseas. The problem with this practice is that the options recommended in overseas guidelines are not necessarily suitable for Japanese clinical practice. A relatively large number of clinical trials have been conducted in Japan in the field of bladder cancer, and the Japanese Urological Association (JUA) considered it appropriate to formulate their own guidelines. These Guidelines present an overview of bladder cancer at each clinical stage, followed by clinical questions that address problems frequently faced in everyday clinical practice. In this English translation of a shortened version of the original Guidelines, we have abridged each overview, summarized each clinical question and its answer, and only included the references we considered of particular importance.

  16. CLINICAL SURFACES -- Activity-Based Computing for Distributed Multi-Display Environments in Hospitals

    DEFF Research Database (Denmark)

    Bardram, Jakob Eyvind; Bunde-Pedersen, Jonathan; Doryab, Afsaneh

    2009-01-01

    and activities that the MDE is being used for. This paper presents a novel approach to support activity-based computing in distributed MDEs, where displays are physically distributed across a large building. CLINICAL SURFACES was designed for clinical work in hospitals, and enables context-sensitive retrieval...... and browsing of patient data on public displays. We present the design and implementation of CLINICAL SURFACES, and report from an evaluation of the system at a large hospital. The evaluation shows that using distributed public displays to support activity-based computing inside a hospital is very useful...... for clinical work, and that the apparent contradiction between maintaining privacy of medical data in a public display environment can be mitigated by the use of CLINICAL SURFACES....

  17. Evidence-based early clinical detection of emerging diseases in food animals and zoonoses: two cases.

    Science.gov (United States)

    Saegerman, Claude; Humblet, Marie-France; Porter, Sarah Rebecca; Zanella, Gina; Martinelle, Ludovic

    2012-03-01

    If diseases of food-producing animals or zoonoses (re-)emerge, early clinical decision making is of major importance. In this particular condition, it is difficult to apply a classic evidence-based veterinary medicine process, because of a lack of available published data. A method based on the partition of field clinical observations (evidences) could be developed as an interesting alternative approach. The classification and regression tree (CART) analysis was used to improve the early clinical detection in two cases of emerging diseases: bovine spongiform encephalopathy (mad cow disease) and bluetongue due to the serotype 8-virus in cattle.

  18. Electronic data capture platform for clinical research based on mobile phones and near field communication technology.

    Science.gov (United States)

    Morak, Jürgen; Schwetz, Verena; Hayn, Dieter; Fruhwald, Friedrich; Schreier, Gunter

    2008-01-01

    Electronic data capture systems support data acquisition for clinical research and enable the evaluation of new investigational medical devices. In case of evaluating a device the most challenging part is the user interface i.e. the solution how to acquire the data within a clinical setting and to synchronize them with a web-based data centre. The aim of this paper is to describe the development of an electronic data capture system with a mobile data input solution based on mobile phones and Near Field Communication technology. This system was evaluated within a real clinical setting and demonstrated high usability, security and reliability.

  19. A Population-Based Clinical Trial of Irinotecan and Carboplatin

    Directory of Open Access Journals (Sweden)

    Derick Lau

    2009-01-01

    Full Text Available Purpose. Phase I trials of anticancer drugs are commonly conducted using the method of modified Fibonacci. We have developed a population-based design for phase I trials of combining anticancer drugs such as irinotecan and carboplatin. Patients and Methods. Intrapatient dose escalation of irinotecan and carboplatin was performed according to a predetermined schema to reach individual dose-limiting toxicity (DLT in 50 patients with solid tumors refractory to previous chemotherapy. The individual toxicity-limiting dose levels were analyzed for normal distribution using the method of Ryan-Joiner and subsequently used to determine a population-based maximum tolerated dose (pMTD. For comparison, a simulation study was performed using the method of modified Fibonacci. Results. The most common dose-limiting toxicities (DLTs included neutropenia (58%, thrombocytopenia (16%, and diarrhea (8%. The frequency of individual toxicity-limiting dose levels of 50 patients approximated a normal distribution. The dose levels associated with individual limiting toxicities ranged from level 1 (irinotecan 100 mg/m2 and carboplatin AUC = 4 mg/mL x min to level 8 (irinotecan 350 mg/m2 and carboplatin AUC = 6. The pMTD was determined to be dose level 3 (150 mg/m2 for irinotecan and AUC = 5 for carboplatin. In contrast, the MTD was determined to be dose level 4 (200 mg/m2 for irinotecan and AUC 5 for carboplatin by modified-Fibonacci simulation. Conclusions. The population-based design of phase I trial allows optimization of dose intensity and derivation of a pMTD. The pMTD has been applied in phase II trial of irinotecan and carboplatin in patients with small-cell lung cancer.

  20. Combination of synchrotron radiation-based Fourier transforms infrared microspectroscopy and confocal laser scanning microscopy to understand spatial heterogeneity in aquatic multispecies biofilms.

    Science.gov (United States)

    Reuben, Sheela; Banas, Krzysztof; Banas, Agnieszka; Swarup, Sanjay

    2014-11-01

    Understanding the spatial heterogeneity within environmental biofilms can provide an insight into compartmentalization of different functions in biofilm communities. We used a non-destructive and label-free method by combining Synchrotron Radiation-based Fourier Transform Infrared Microspectroscopy (SR-FTIR) with Confocal Laser Scanning Microscopy (CLSM) to distinguish the spatial chemical changes within multispecies biofilms grown from natural storm waters in flow cells. Among the different surfaces tested for biofilm growth and optimal imaging, mylar membranes were most suited and it enabled successful spatial infrared imaging of natural biofilms for obtaining reliable and interpretable FTIR spectra. Time series analysis of biofilm growth showed that influx of water during biofilm growth, results in significant changes in biofilm formation. Early biofilms showed active nutrient acquisition and desiccation tolerance mechanisms corresponding with accumulation of secreted proteins. Statistical approach used for the evaluation of chemical spectra allowed for clustering and classification of various regions of the biofilm. Microheterogeneity was observed in the polymeric components of the biofilm matrix, including cellulose, glycocalyx and dextran-like molecules. Fructan and glycan-rich regions were distinguishable and glycocalyx was abundant in the strongly adhering peripheral regions of biofilms. Inner core showed coexistence of oxygen dimers and ferrihydrite that will likely support growth of Fe (II)-oxidising bacteria. The combined SR-FTIR microspectroscopy and CSLM approach for complex natural biofilms described here will be useful both in understanding heterogeneity of matrix components and in correlating functions of juxtaposed microbial species in complex natural biofilms with physicochemical microenvironment to which they are exposed.

  1. Preparing a 21st century workforce: is it time to consider clinically based, competency-based training of health practitioners?

    Science.gov (United States)

    Nancarrow, Susan A; Moran, Anna M; Graham, Iain

    2014-02-01

    Health workforce training in the 21st century is still based largely on 20th century healthcare paradigms that emphasise professionalisation at the expense of patient-focussed care. This is illustrated by the paradox of increased training times for health workers that have corresponded with workforce shortages, the limited career options and pathways for paraprofessional workers, and inefficient clinical training models that detract from, rather than add to, service capacity. We propose instead that a 21st century health workforce training model should be: situated in the clinical setting and supported by outsourced university training (not the other way around); based on the achievement of specific milestones rather than being time-defined; and incorporate para-professional career pathways that allow trainees to 'step-off' with a useable qualification following the achievement of specific competencies. Such a model could be facilitated by existing technology and clinical training infrastructure, with enormous potential for economies of scale in the provision of formal training. The benefits of a clinically based, competency-based model include an increase in clinical service capacity, and clinical training resources become a resource for the delivery of healthcare, not just education. Existing training models are unsustainable, and are not preparing a workforce with the flexibility the 21st century demands.

  2. Applications of orientation mapping by scanning and transmission electron microscopy

    DEFF Research Database (Denmark)

    Juul Jensen, D.

    1997-01-01

    The potentials of orientation mapping techniques (in the following referred to as OIM) for studies of thermomechanical processes are analysed. Both transmission electron microscopy (TEM) and scanning electron microscopy (SEM) based OIM techniques are considered. Among the thermomechanical processes...

  3. Clinical capabilities of graduates of an outcomes-based integrated medical program

    Directory of Open Access Journals (Sweden)

    Scicluna Helen A

    2012-06-01

    Full Text Available Abstract Background The University of New South Wales (UNSW Faculty of Medicine replaced its old content-based curriculum with an innovative new 6-year undergraduate entry outcomes-based integrated program in 2004. This paper is an initial evaluation of the perceived and assessed clinical capabilities of recent graduates of the new outcomes-based integrated medical program compared to benchmarks from traditional content-based or process-based programs. Method Self-perceived capability in a range of clinical tasks and assessment of medical education as preparation for hospital practice were evaluated in recent graduates after 3 months working as junior doctors. Responses of the 2009 graduates of the UNSW’s new outcomes-based integrated medical education program were compared to those of the 2007 graduates of UNSW’s previous content-based program, to published data from other Australian medical schools, and to hospital-based supervisor evaluations of their clinical competence. Results Three months into internship, graduates from UNSW’s new outcomes-based integrated program rated themselves to have good clinical and procedural skills, with ratings that indicated significantly greater capability than graduates of the previous UNSW content-based program. New program graduates rated themselves significantly more prepared for hospital practice in the confidence (reflective practice, prevention (social aspects of health, interpersonal skills (communication, and collaboration (teamwork subscales than old program students, and significantly better or equivalent to published benchmarks of graduates from other Australian medical schools. Clinical supervisors rated new program graduates highly capable for teamwork, reflective practice and communication. Conclusions Medical students from an outcomes-based integrated program graduate with excellent self-rated and supervisor-evaluated capabilities in a range of clinically-relevant outcomes. The program

  4. Multiphoton microscopy in defining liver function

    Science.gov (United States)

    Thorling, Camilla A.; Crawford, Darrell; Burczynski, Frank J.; Liu, Xin; Liau, Ian; Roberts, Michael S.

    2014-09-01

    Multiphoton microscopy is the preferred method when in vivo deep-tissue imaging is required. This review presents the application of multiphoton microscopy in defining liver function. In particular, multiphoton microscopy is useful in imaging intracellular events, such as mitochondrial depolarization and cellular metabolism in terms of NAD(P)H changes with fluorescence lifetime imaging microscopy. The morphology of hepatocytes can be visualized without exogenously administered fluorescent dyes by utilizing their autofluorescence and second harmonic generation signal of collagen, which is useful in diagnosing liver disease. More specific imaging, such as studying drug transport in normal and diseased livers are achievable, but require exogenously administered fluorescent dyes. If these techniques can be translated into clinical use to assess liver function, it would greatly improve early diagnosis of organ viability, fibrosis, and cancer.

  5. [Evidence-Based Knowledge Translation: From Scientific Evidence to Clinical Nursing Practice].

    Science.gov (United States)

    Chen, Kee-Hsin; Kao, Ching-Chiu; Chen, Chiehfeng

    2016-12-01

    In 1992, Gordon Guyatt coined the term "evidence-based medicine", which has since attracted worldwide attention. In 2007, the Institute of Medicine's Roundtable on Evidence-Based Medicine set the goal that 90% of clinical decisions would be supported by accurate, timely, and up-to-date clinical information and would reflect the best available evidence by 2020. However, the chasm between knowing and doing remains palpable. In 2000, the Canadian Institute of Health Research applied the term "knowledge translation" to describe the bridge that is necessary to cross the gap between research knowledge and clinical practice. The present paper outlines the conceptual framework, barriers, and promotion strategies for evidence-based knowledge translation and shares clinical experience related to overcoming the seven layers of leakage (aware, accepted, applicable, able, acted on, agreed, and adhered to). We hope that this paper can enhance the public well-being and strengthen the future health care system.

  6. Clinical gait data analysis based on Spatio-Temporal features

    CERN Document Server

    Katiyar, Rohit

    2010-01-01

    Analysing human gait has found considerable interest in recent computer vision research. So far, however, contributions to this topic exclusively dealt with the tasks of person identification or activity recognition. In this paper, we consider a different application for gait analysis and examine its use as a means of deducing the physical well-being of people. The proposed method is based on transforming the joint motion trajectories using wavelets to extract spatio-temporal features which are then fed as input to a vector quantiser; a self-organising map for classification of walking patterns of individuals with and without pathology. We show that our proposed algorithm is successful in extracting features that successfully discriminate between individuals with and without locomotion impairment.

  7. Person-centric clinical trials: an opportunity for the good clinical practice (GCP)-practice-based research network.

    Science.gov (United States)

    Curro, Frederick A; Robbins, Dennis A; Millenson, Michael L; Fox, Chester H; Naftolin, Frederick

    2013-10-01

    Practice-based research networks (PBRNs) can function as a platform for delivery of patient-centered care consistent with the Patient Protection and Affordable Care Act. Patient-centered (centric) clinical studies encourage the patient to be an integral part of study design and outcome. The patient's electronic health record contributes to the shared national health care data set. PBRNs integrate health care data in real time at the point of care and reflect the full context of the person's health. PBRNs designed under the principles of good clinical practice (GCP) validate studies related to comparative effectiveness research and drug development. PBRNs can generate large amounts of data from known patient histories so that side effects can be assessed in their totality. The larger and more diverse number of patients recruited suggests that point-of-care-data, where both provider and patient participate in the treatment, may be more robust in that side effects, drug-drug interactions and number of concomitant medications used may be identified earlier in the development process. The GCP PBRN concept affords continuous patient information for both care and research purposes. These all contribute to an ethical approach for the pharmaceutical industry to generate clinical research data for regulatory submission and to contribute to a HIPAA-compliant national database that could contribute to improved health care delivery and pharmacovigilance.

  8. All-optical photoacoustic microscopy

    Directory of Open Access Journals (Sweden)

    Sung-Liang Chen

    2015-12-01

    Full Text Available Three-dimensional photoacoustic microscopy (PAM has gained considerable attention within the biomedical imaging community during the past decade. Detecting laser-induced photoacoustic waves by optical sensing techniques facilitates the idea of all-optical PAM (AOPAM, which is of particular interest as it provides unique advantages for achieving high spatial resolution using miniaturized embodiments of the imaging system. The review presents the technology aspects of optical-sensing techniques for ultrasound detection, such as those based on optical resonators, as well as system developments of all-optical photoacoustic systems including PAM, photoacoustic endoscopy, and multi-modality microscopy. The progress of different AOPAM systems and their representative applications are summarized.

  9. BASED TO CLINICAL CASE. VON HIPLEA-LINDAU SYNDROME

    Directory of Open Access Journals (Sweden)

    Brzeziński Piotr

    2011-01-01

    Full Text Available von Hippel-Lindau syndrome (VHL is a rare, genetic multi-system disorder characterized by the abnormal growth of tumors in certain parts of the body (angiomatosis. The tumors of the central nervous system (CNS are benign and are comprised of a nest of blood vessels and are called hemangioblastomas. Hemangioblastomas may develop in the brain, the retina of the eyes, and other areas of the nervous system. Other types of tumors develop in the adrenal glands, the kidneys, or the pancreas. Symptoms of VHL vary among patients and depend on the size and location of the tumors. Symptoms may include headaches, problems with balance and walking, dizziness, weakness of the limbs, vision problems, and high blood pressure. Cysts (fluid-filled sacs and/or tumors (benign or cancerous may develop around the hemangioblastomas and cause the symptoms listed above. Individuals with VHL are also at a higher risk than normal for certain types of cancer, especially kidney cancer. Based on the case of 30-year old patient with characteristics of von Hippel-Lindau syndrome as phakomatosis.

  10. Simulation-based education for building clinical teams

    Directory of Open Access Journals (Sweden)

    Marshall Stuart

    2010-01-01

    Full Text Available Failure to work as an effective team is commonly cited as a cause of adverse events and errors in emergency medicine. Until recently, individual knowledge and skills in managing emergencies were taught, without reference to the additional skills required to work as part of a team. Team training courses are now becoming commonplace, however their strategies and modes of delivery are varied. Just as different delivery methods of traditional education can result in different levels of retention and transfer to the real world, the same is true in team training of the material in different ways in traditional forms of education may lead to different levels of retention and transfer to the real world, the same is true in team training. As team training becomes more widespread, the effectiveness of different modes of delivery including the role of simulation-based education needs to be clearly understood. This review examines the basis of team working in emergency medicine, and the components of an effective emergency medical team. Lessons from other domains with more experience in team training are discussed, as well as the variations from these settings that can be observed in medical contexts. Methods and strategies for team training are listed, and experiences in other health care settings as well as emergency medicine are assessed. Finally, best practice guidelines for the development of team training programs in emergency medicine are presented.

  11. Validation of wet mount microscopy against Trichomonas culture among women of reproductive age group in Western province, Sri Lanka.

    Science.gov (United States)

    Banneheke, H; Fernandopulle, R; Gunasekara, U; Barua, A; Fernando, N; Wickremasinghe, R

    2015-06-01

    Wet mount microscopy is the most commonly used diagnostic method for trichomoniasis in clinical diagnostic services all over the world including Sri Lanka due to its availability, simplicity and is relatively inexpensive. However, Trichomonas culture and PCR are the gold standard tests. Unfortunately, neither the culture nor PCR is available for the diagnosis of trichomoniasis in Sri Lanka. Thus, it is important to validate the wet mount microscopy as it is the only available diagnostic test and has not been validated to date in Sri Lanka. The objective was to evaluate the validity and reliability of wet mount microscopy against gold standard Trichomonas culture among clinic based population of reproductive age group women in Western province, Sri Lanka. Women attending hospital and institutional based clinics were enrolled. They were interviewed and high vaginal swabs were taken for laboratory diagnosis by culture and wet mount microscopy. There were 601 participants in the age group of 15-45 years. Wet mount microscopy showed 68% sensitivity, 100% specificity, 100% positive (PPV) and 98% negative predictive values (NPV) (P=0.001, kappa=0.803) respectively against the gold standard culture. The area under the ROC curve was 0.840. Sensitivity of wet mount microscopy is low. However it has high validity and reliability as a specific diagnostic test for trichomoniasis. If it is to be used among women of reproductive age group in Western province, Sri Lanka, a culture method could be adopted as a second test to confirm the negative wet mount for symptomatic patients.

  12. Optical imaging. Expansion microscopy.

    Science.gov (United States)

    Chen, Fei; Tillberg, Paul W; Boyden, Edward S

    2015-01-30

    In optical microscopy, fine structural details are resolved by using refraction to magnify images of a specimen. We discovered that by synthesizing a swellable polymer network within a specimen, it can be physically expanded, resulting in physical magnification. By covalently anchoring specific labels located within the specimen directly to the polymer network, labels spaced closer than the optical diffraction limit can be isotropically separated and optically resolved, a process we call expansion microscopy (ExM). Thus, this process can be used to perform scalable superresolution microscopy with diffraction-limited microscopes. We demonstrate ExM with apparent ~70-nanometer lateral resolution in both cultured cells and brain tissue, performing three-color superresolution imaging of ~10(7) cubic micrometers of the mouse hippocampus with a conventional confocal microscope.

  13. Second harmonic generation microscopy

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline; Brewer, Jonathan R.; Risbo, Jens;

    2010-01-01

    Myofibers and collagen show non-linear optical properties enabling imaging using second harmonic generation (SHG) microscopy. The technique is evaluated for use as a tool for real-time studies of thermally induced changes in thin samples of unfixed and unstained pork. The forward and the backward......-temperature endotherm peak observable in the differential scanning calorimetry (DSC) thermograms. DSC analysis of epimysium, the connective tissue layer that enfold skeletal muscles, produces one large endotherm starting at 57 °C and peaking at 59.5 °C. SHG microscopy of collagen fibers reveals a variability of thermal...... indicating regions of much higher thermal stability. It is seen that the benefits of the structural and temporal information available from SHG microscopy reveals complementary information to a traditional DSC measurement and enables a more complete understanding of the thermal denaturation process....

  14. Confocal Raman Microscopy

    CERN Document Server

    Dieing, Thomas; Toporski, Jan

    2011-01-01

    Confocal Raman Microscopy is a relatively new technique that allows chemical imaging without specific sample preparation. By integrating a sensitive Raman spectrometer within a state-of-the-art microscope, Raman microscopy with a spatial resolution down to 200nm laterally and 500nm vertically can be achieved using visible light excitation. Recent developments in detector and computer technology as well as optimized instrument design have reduced integration times of Raman spectra by orders of magnitude, so that complete images consisting of tens of thousands of Raman spectra can be acquired in seconds or minutes rather than hours, which used to be standard just one decade ago. The purpose of this book is to provide the reader a comprehensive overview of the rapidly developing field of Confocal Raman Microscopy and its applications.

  15. Primary oral health service provision in Aboriginal Medical Services-based dental clinics in Western Australia.

    Science.gov (United States)

    Kruger, Estie; Perera, Irosha; Tennant, Marc

    2010-01-01

    Australians living in rural and remote areas have poorer access to dental care. This situation is attributed to workforce shortages, limited facilities and large distances to care centres. Against this backdrop, rural and remote Indigenous (Aboriginal) communities in Western Australia seem to be more disadvantaged because evidence suggests they have poorer oral health than non-Indigenous people. Hence, provision of dental care for Aboriginal populations in culturally appropriate settings in rural and remote Western Australia is an important public health issue. The aim of this research was to compare services between the Aboriginal Medical Services (AMS)-based clinics and a typical rural community clinic. A retrospective analysis of patient demographics and clinical treatment data was undertaken among patients who attended the dental clinics over a period of 6 years from 1999 to 2004. The majority of patients who received dental care at AMS dental clinics were Aboriginal (95.3%), compared with 8% at the non-AMS clinic. The rate of emergency at the non-AMS clinic was 33.5%, compared with 79.2% at the AMS clinics. The present study confirmed that more Indigenous patients were treated in AMS dental clinics and the mix of dental care provided was dominated by emergency care and oral surgery. This indicated a higher burden of oral disease and late utilisation of dental care services (more focus on tooth extraction) among rural and remote Indigenous people in Western Australia.

  16. Transmission electron microscopy study for investigating high-temperature reliability of Ti{sub 10}W{sub 90}-based and Ta-based diffusion barriers up to 600 C

    Energy Technology Data Exchange (ETDEWEB)

    Budhiman, Nando; Schuermann, Ulrich; Kienle, Lorenz [Institute of Material Science, Christian-Albrechts-Universitaet, Kiel (Germany); Jensen, Bjoern [Fraunhofer Institute for Silicon Technology, Itzehoe (Germany); Chemnitz, Steffen; Wagner, Bernhard [Institute of Material Science, Christian-Albrechts-Universitaet, Kiel (Germany); Fraunhofer Institute for Silicon Technology, Itzehoe (Germany)

    2016-04-15

    Abstractauthoren Transmission electron microscopy (TEM) analysis, including energy dispersive X-ray (EDX) (elemental mapping, line, and point measurements) and energy filtered TEM (EFTEM) methods, is applied to investigate the high temperature reliability, especially material diffusion, of two types of diffusion barriers: titanium-tungsten-based (Ti{sub 10}W{sub 90}-based) and tantalum-based (Ta-based), with nickel (Ni) layer on top. Both barriers were deposited as a form of stacked layers on sili-con (Si) wafers using the physical vapor deposition (PVD) technique. TEM analysis is performed on both barriers before and after annealing (at 600 C for 24 h inside a vacuum chamber). No diffusion of material into the Si substrate as observed. Additionally, only diffusion between the Ni and adjoining Ti{sub 10}W{sub 90} layers, and between Ni and adjoining Ta layers in the Ti{sub 10}W{sub 90}-based and Ta-based barriers, respectively, are observed due to annealing. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Basic confocal microscopy

    Directory of Open Access Journals (Sweden)

    Manuela Monti

    2012-03-01

    Full Text Available This is an eleven chapter’s effort done by a bunch of Authors coordinated by Prof. R.L. Price and W.G. Jerome (who have personally written almost half of the book that with great skills are revealing us the secrets of confocal microscopy. Considering the significant progresses in different fields of biology, confocal microscopy is extremely important to dynamically see all the different molecules involved in the controlling networks build up by gene expressions in time and space. Necessary prerequisites to accomplish such goals are some fundamental microscopic technologies well and clearly presented in the first chapters....

  18. Spectrally encoded confocal microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tearney, G.J.; Webb, R.H.; Bouma, B.E. [Wellman Laboratories of Photomedicine, Massachusetts General Hospital, 50 Blossom Street, BAR 703, Boston, Massachusetts 02114 (United States)

    1998-08-01

    An endoscope-compatible, submicrometer-resolution scanning confocal microscopy imaging system is presented. This approach, spectrally encoded confocal microscopy (SECM), uses a quasi-monochromatic light source and a transmission diffraction grating to detect the reflectivity simultaneously at multiple points along a transverse line within the sample. Since this method does not require fast spatial scanning within the probe, the equipment can be miniaturized and incorporated into a catheter or endoscope. Confocal images of an electron microscope grid were acquired with SECM to demonstrate the feasibility of this technique. {copyright} {ital 1998} {ital Optical Society of America}

  19. Fungal Keratitis - Improving Diagnostics by Confocal Microscopy

    Directory of Open Access Journals (Sweden)

    Esben Nielsen

    2013-12-01

    Full Text Available Purpose: Introducing a simple image grading system to support the interpretation of in vivo confocal microscopy (IVCM images in filamentous fungal keratitis. Setting: Clinical and confocal studies took place at the Department of Ophthalmology, Aarhus University Hospital, Denmark. Histopathological analysis was performed at the Eye Pathology Institute, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark. Methods: A recent series of consecutive patients with filamentous fungal keratitis is presented to demonstrate the results from in-house IVCM. Based upon our experience with IVCM and previously published images, we composed a grading system for interpreting IVCM images of filamentous fungal keratitis. Results: A recent case series of filamentous fungal keratitis from 2011 to 2012 was examined. There were 3 male and 3 female patients. Mean age was 44.5 years (range 12-69, 6 out of 17 (35% cultures were positive and a total of 6/7 (86% IVCM scans were positive. Three different categories of IVCM results for the grading of diagnostic certainty were formed. Conclusion: IVCM is a valuable tool for diagnosing filamentous fungal keratitis. In order to improve the reliability of IVCM, we suggest implementing a simple and clinically applicable grading system for aiding the interpretation of IVCM images of filamentous fungal keratitis.

  20. Defining Emergency Department Necessary Policies Based on Clinical Governance Accreditation Scores

    Directory of Open Access Journals (Sweden)

    Mehrdad Esmailian

    2015-05-01

    Full Text Available Introduction: The role of accreditation scheme in quality improvement of emergency departments (ED has not been thoroughly evaluated in studies. Therefore, this study was designed to appraise the effects of policies defined based on clinical governance accreditation scores, on improvement of the procedures in ED. Methods: The present cohort study was carried out in the ED of Alzahra University Hospital, Isfahan, Iran in 2012-2013. In 2012 the deficiencies in ED of this hospital was determined based on clinical governance indicators. Then the deficiencies were classified based on their importance and changes were made in the ED. Finally, the effects of the changes were evaluated in August 2013. Results: The evaluation made in 2012 showed that 23 clinical and non-clinical procedures were carried out with deficiencies. Over the mentioned period, 6 (26.1% procedures were not done at all, while 17 (73.9% were done without a policy and irregularly. The overall score for clinical and non-clinical procedures in the ED before carrying out the accreditation scheme was 43 / 230 (18.7% of the maximum possible score. The score was raised to 222 equal to 96.5% of the maximum possible score after carrying out the scheme. This increase was statistically significant (p < 0.001. Conclusion: The findings of the present study showed that defining policies for improving the procedures carried out in ED based on accreditation scheme leads to improvement of medical services in ED.

  1. Clinical Outlook for Type-1 and FOXP3+ T Regulatory Cell-Based Therapy

    Science.gov (United States)

    Gregori, Silvia; Passerini, Laura; Roncarolo, Maria-Grazia

    2015-01-01

    T regulatory cells (Tregs) are subsets of T lymphocytes specialized in modulating antigen-specific immune responses in vivo. Hence, Tregs represent an ideal therapeutic tool to control detrimental immune reactions. Based on solid pre-clinical results, investigators started testing the safety and efficacy of Treg-based therapies in humans. Despite promising results, a number of issues remain to be solved. We will discuss the results obtained from clinical trials and the challenges and risks we are facing in the further development of Treg-based therapies. PMID:26635807

  2. Competency-based education in a clinical course in conservative dentistry.

    Science.gov (United States)

    Yip, H K; Smales, R J; Newsome, P R; Chu, F C; Chow, T W

    2001-11-10

    The conceptual difference between a competency-based education and an education based upon a conventional dental curriculum is, perhaps, the starting point for the development of new curricula. The two systems are not, in themselves, exclusive. There is common ground to be found, and the concept of combining instruction with competency-based learning experiences is emerging in recent publications. This paper describes a competency-based approach applied to a clinical course in conservative dentistry. The learning outcomes of the fourth-year dental students in the new course were assessed using methods that included continuous clinical assessments, student presentations and peer-group reflective evaluations, patient management reviews, a clinical progress examination, the range and amount of work completed, and a written examination and viva voce. Different weightings were given to various elements of the assessment. A formal student assessment of the course rated it as being satisfactory.

  3. Safe in the city: developing an effective video-based intervention for STD clinic waiting rooms.

    Science.gov (United States)

    Myint-U, Athi; Bull, Sheana; Greenwood, Gregory L; Patterson, Jocelyn; Rietmeijer, Cornelis A; Vrungos, Shelley; Warner, Lee; Moss, Jesse; O'Donnell, Lydia N

    2010-05-01

    There is a strong need for inexpensive, easily administered HIV and STD prevention interventions that are highly replicable and appealing to diverse clinic audiences. This article describes the four-step iterative and collaborative process used by the Safe City Study Group to design and develop a brief video-based intervention: Safe in the City. Step 1 involves identification of an appropriate intervention medium, a theoretical framework, and key messages; Step 2, collaboration with a film company to integrate the framework and key messages into an entertaining product; Step 3, facilitation of a multistep participatory process involving input from members of the priority audience (clinic patients), clinic staff, and community reviewers; and Step 4, pilot-testing to determine structural barriers to patients' viewing the video in clinic waiting rooms. Safe in the City has been demonstrated to reduce incident STDs among clinic patients in three cities in the United States.

  4. ON THE IDENTITY OF KARLODINIUM VENEFICUM AND DESCRIPTION OF KARLODINIUM ARMIGER SP. NOV. (DINOPHYCEAE), BASED ON LIGHT AND ELECTRON MICROSCOPY, NUCLEAR-ENCODED LSU RDNA, AND PIGMENT COMPOSITION

    DEFF Research Database (Denmark)

    Bergholtz, Trine; Daugbjerg, Niels; Moestrup, Øjvind;

    2006-01-01

    An undescribed species of the dinoflagellate genus Karlodinium J. Larsen (viz. K. armiger sp. nov.) is described from Alfacs Bay (Spain), using light and electron microscopy, pigment composition, and partial large subunit (LSU) rDNA sequence. The new species differs from the type species of Karlo...

  5. Development and clinical study of mobile 12-lead electrocardiography based on cloud computing for cardiac emergency.

    Science.gov (United States)

    Fujita, Hideo; Uchimura, Yuji; Waki, Kayo; Omae, Koji; Takeuchi, Ichiro; Ohe, Kazuhiko

    2013-01-01

    To improve emergency services for accurate diagnosis of cardiac emergency, we developed a low-cost new mobile electrocardiography system "Cloud Cardiology®" based upon cloud computing for prehospital diagnosis. This comprises a compact 12-lead ECG unit equipped with Bluetooth and Android Smartphone with an application for transmission. Cloud server enables us to share ECG simultaneously inside and outside the hospital. We evaluated the clinical effectiveness by conducting a clinical trial with historical comparison to evaluate this system in a rapid response car in the real emergency service settings. We found that this system has an ability to shorten the onset to balloon time of patients with acute myocardial infarction, resulting in better clinical outcome. Here we propose that cloud-computing based simultaneous data sharing could be powerful solution for emergency service for cardiology, along with its significant clinical outcome.

  6. Self-guided clinical cases for medical students based on postmortem CT scans of cadavers.

    Science.gov (United States)

    Bohl, Michael; Francois, Webster; Gest, Thomas

    2011-07-01

    In the summer of 2009, we began full body computed tomography (CT) scanning of the pre-embalmed cadavers in the University of Michigan Medical School (UMMS) dissection lab. We theorized that implementing web-based, self-guided clinical cases based on postmortem CT (PMCT) scans would result in increased student appreciation for the clinical relevance of anatomy, increased knowledge of cross-sectional anatomy, and increased ability to identify common pathologies on CT scans. The PMCT scan of each cadaver was produced as a DICOM dataset, and then converted into a Quicktime movie file using Osirix software. Clinical cases were researched and written by the authors, and consist of at least one Quicktime movie of a PMCT scan surrounded by a novel navigation interface. To assess the value of these clinical cases we surveyed medical students at UMMS who are currently using the clinical cases in their coursework. Students felt the clinical cases increased the clinical relevance of anatomy (mean response 7.77/10), increased their confidence finding anatomical structures on CT (7.00/10), and increased their confidence recognizing common pathologies on CT (6.17/10). Students also felt these clinical cases helped them synthesize material from numerous courses into an overall picture of a given disease process (7.01/10). These results support the conclusion that our clinical cases help to show students why the anatomy they are learning is foundational to their other coursework. We would recommend the use of similar clinical cases to any medical school utilizing cadaver dissection as a primary teaching method in anatomy education.

  7. Scanning ultrafast electron microscopy.

    Science.gov (United States)

    Yang, Ding-Shyue; Mohammed, Omar F; Zewail, Ahmed H

    2010-08-24

    Progress has been made in the development of four-dimensional ultrafast electron microscopy, which enables space-time imaging of structural dynamics in the condensed phase. In ultrafast electron microscopy, the electrons are accelerated, typically to 200 keV, and the microscope operates in the transmission mode. Here, we report the development of scanning ultrafast electron microscopy using a field-emission-source configuration. Scanning of pulses is made in the single-electron mode, for which the pulse contains at most one or a few electrons, thus achieving imaging without the space-charge effect between electrons, and still in ten(s) of seconds. For imaging, the secondary electrons from surface structures are detected, as demonstrated here for material surfaces and biological specimens. By recording backscattered electrons, diffraction patterns from single crystals were also obtained. Scanning pulsed-electron microscopy with the acquired spatiotemporal resolutions, and its efficient heat-dissipation feature, is now poised to provide in situ 4D imaging and with environmental capability.

  8. Ballistic hole magnetic microscopy

    NARCIS (Netherlands)

    Haq, E.; Banerjee, T.; Siekman, M.H.; Lodder, J.C.; Jansen, R.

    2005-01-01

    A technique to study nanoscale spin transport of holes is presented: ballistic hole magnetic microscopy. The tip of a scanning tunneling microscope is used to inject hot electrons into a ferromagnetic heterostructure, where inelastic decay creates a distribution of electron-hole pairs. Spin-dependen

  9. Single particle electron microscopy

    NARCIS (Netherlands)

    Boekema, Egbert J.; Folea, Mihaela; Kouril, Roman; Kouřil, Roman

    2009-01-01

    Electron microscopy (EM) in combination with image analysis is a powerful technique to study protein structures at low, medium, and high resolution. Since electron micrographs of biological objects are very noisy, improvement of the signal-to-noise ratio by image processing is an integral part of EM

  10. General practice-based clinical trials in Germany - a problem analysis

    Directory of Open Access Journals (Sweden)

    Hummers-Pradier Eva

    2012-11-01

    Full Text Available Abstract Background In Germany, clinical trials and comparative effectiveness studies in primary care are still very rare, while their usefulness has been recognised in many other countries. A network of researchers from German academic general practice has explored the reasons for this discrepancy. Methods Based on a comprehensive literature review and expert group discussions, problem analyses as well as structural and procedural prerequisites for a better implementation of clinical trials in German primary care are presented. Results In Germany, basic biomedical science and technology is more reputed than clinical or health services research. Clinical trials are funded by industry or a single national programme, which is highly competitive, specialist-dominated, exclusive of pilot studies, and usually favours innovation rather than comparative effectiveness studies. Academic general practice is still not fully implemented, and existing departments are small. Most general practitioners (GPs work in a market-based, competitive setting of small private practices, with a high case load. They have no protected time or funding for research, and mostly no research training or experience. Good Clinical Practice (GCP training is compulsory for participation in clinical trials. The group defined three work packages to be addressed regarding clinical trials in German general practice: (1 problem analysis, and definition of (2 structural prerequisites and (3 procedural prerequisites. Structural prerequisites comprise specific support facilities for general practice-based research networks that could provide practices with a point of contact. Procedural prerequisites consist, for example, of a summary of specific relevant key measures, for example on a web platform. The platform should contain standard operating procedures (SOPs, templates, checklists and other supporting materials for researchers. Conclusion All in all, our problem analyses revealed that

  11. Correlative Stochastic Optical Reconstruction Microscopy and Electron Microscopy

    OpenAIRE

    Doory Kim; Deerinck, Thomas J.; Sigal, Yaron M.; Babcock, Hazen P.; Ellisman, Mark H.; Xiaowei Zhuang

    2015-01-01

    Correlative fluorescence light microscopy and electron microscopy allows the imaging of spatial distributions of specific biomolecules in the context of cellular ultrastructure. Recent development of super-resolution fluorescence microscopy allows the location of molecules to be determined with nanometer-scale spatial resolution. However, correlative super-resolution fluorescence microscopy and electron microscopy (EM) still remains challenging because the optimal specimen preparation and ima...

  12. Implementing ward based clinical pharmacy services in an Ethiopian University Hospital

    Directory of Open Access Journals (Sweden)

    Mekonnen AB

    2013-03-01

    Full Text Available Background: Clinical pharmacy practice has developed internationally to expand the role of a pharmacist well beyond the traditional roles of compounding, dispensing and supplying drugs to roles more directly in caring for patients. Studies on the activities of the clinical pharmacist in an inpatient ward in resource constrained settings are scarce, however.Objective: To assess ward based clinical pharmacy services in an internal medicine ward of Jimma University Specialized Hospital. Methods: The study was carried out in the internal medicine ward from March to April, 2011 at Jimma University Specialized Hospital. The study design was a prospective observational study where pharmaceutical care services provided by clinical pharmacists for inpatients were documented over a period of two months. Interventions like optimization of rational drug use and physician acceptance of these recommendations were documented. Clinical significance of interventions was evaluated by an independent team (1 internist, 1 clinical pharmacologist using a standardized method for categorizing drug related problems (DRPs. Results: A total of 149 drug related interventions conducted for 48 patients were documented; among which 133(89.3% were clinical pharmacists initiated interventions and 16(10.7% interventions were initiated by other health care professionals. The most frequent DRPs underlying interventions were unnecessary drug therapy, 36(24.2%; needs additional drug therapy, 34(22.8% and noncompliance, 29(19.5%. The most frequent intervention type was change of dosage/instruction for use, 23(15.4%. Acceptance rate by physicians was 68.4%. Among the interventions that were rated as clinically significant, 46(48.9% and 25(26.6% had major and moderate clinical importance respectively. Conclusion: Involving trained clinical pharmacists in the healthcare team leads to clinically relevant and well accepted optimization of medicine use in a resource limited settings. This

  13. Evaluating research for clinical significance: using critically appraised topics to enhance evidence-based neuropsychology.

    Science.gov (United States)

    Bowden, Stephen C; Harrison, Elise J; Loring, David W

    2014-01-01

    Meehl's (1973, Psychodiagnosis: Selected papers. Minneapolis: University of Minnesota Press) distinction between statistical and clinical significance holds special relevance for evidence-based neuropsychological practice. Meehl argued that despite attaining statistical significance, many published findings have limited practical value since they do not inform clinical care. In the context of an ever expanding clinical research literature, accessible methods to evaluate clinical impact are needed. The method of Critically Appraised Topics (Straus, Richardson, Glasziou, & Haynes, 2011, Evidence-based medicine: How to practice and teach EBM (4th ed.). Edinburgh: Elsevier Churchill-Livingstone) was developed to provide clinicians with a "toolkit" to facilitate implementation of evidence-based practice. We illustrate the Critically Appraised Topics method using a dementia screening example. We argue that the skills practiced through critical appraisal provide clinicians with methods to: (1) evaluate the clinical relevance of new or unfamiliar research findings with a focus on patient benefit, (2) help focus of research quality, and (3) incorporate evaluation of clinical impact into educational and professional development activities.

  14. Patient-based not problem-based learning: An Oslerian approach to clinical skills, looking back to move forward

    Directory of Open Access Journals (Sweden)

    Franklyn-Miller A

    2009-01-01

    Full Text Available Context : There have been significant changes in the past decade in both the curriculum and its delivery, in undergraduate medical education. Many of these changes have been made simultaneously, preventing clear assessment of outcome measures. The move away from a pre-clinical science grounding, to an integrated ′problem-based learning (PBL approach′ has been widespread in many countries across the world. Purpose : One effect of these changes has been the way in which clinical skills, in particular history and examination are taught. By integrating clinical scenarios earlier in the undergraduate course, clinical skills are increasingly taught in tutorials. This approach, when used in the pre-clinical setting may have shortcomings in the development of the ability to construct a differential diagnosis. There has been little evidence that PBL improves problem-solving ability and this is critical to the differential diagnostic process. The concurrent decline in anatomical teaching and understanding contributes to this difficulty. Discussion : The authors outline a model which clinicians can re-emphasize to students and juniors based on the fundamentals of clinical practice. The apprenticeship is more important than ever in the days of small group learning. The relinquishing of the traditional model of undergraduate medicine is of concern. The effects of educational reform should be examined by further research into the competencies of graduates entering higher professional training, before it is accepted that this change has been for the better.

  15. Clinical Holistic Medicine: Tools for a Medical Science Based on Consciousness

    Directory of Open Access Journals (Sweden)

    Søren Ventegodt

    2004-01-01

    Full Text Available Biomedicine focuses on the biochemistry of the body, while consciousness-based medicine — holistic medicine — focuses on the individual's experiences and conscious whole (Greek: holos, whole. Biomedicine perceives diseases as mechanical errors at the micro level, while consciousness-based medicine perceives diseases as disturbances in attitudes, perceptions, and experiences at the macro level — in the organism as a whole. Thus, consciousness-based medicine is based on the whole individual, while biomedicine is based on its smallest parts, the molecules. These two completely different points of departure make the two forms of medicine very different; they represent two different mind sets and two different frames of reference or medical paradigms. This paper explains the basic tools of clinical holistic medicine based on the life mission theory and holistic process theory, with examples of holistic healing from the holistic medical clinic.

  16. Outcomes assessment of case-based writing exercises in a veterinary clinical pathology course.

    Science.gov (United States)

    Sharkey, Leslie; Michael, Helen; LeBeau, Brandon; Center, Bruce; Wingert, Deb

    2012-01-01

    Our second-year core clinical pathology course uses free-response case-based learning exercises in an otherwise traditional lecture or laboratory course format to augment the development of skills in application of knowledge and critical thinking and clinical reasoning. We previously reported increased learner confidence accompanied by perceived improvements in understanding and ability to apply information, along with enhanced feelings of preparedness for examinations that students attributed to the case-based exercises. The current study prospectively follows a cohort of students to determine the ability of traditional multiple-choice versus free-response case-based assessments to predict future academic performance and to determine if the perceived value of the case-based exercises persists through the curriculum. Our data show that after holding multiple-choice scores constant, better performance on case-based free-response exercises led to higher GPA and better class rank in the second and third years and better class rank in the fourth year. Students in clinical rotations reported that the case-based approach was superior to traditional lecture or multiple-choice exam format for learning clinical reasoning, retaining factual information, organizing information, communicating medical information clearly to colleagues in clinical situations, and preparing high quality medical records. In summary, this longitudinal study shows that case-based free-response writing assignments are efficacious above and beyond standard measures in determining students' GPAs and class rank and in students' acquisition of knowledge, skills, and clinical reasoning. Students value these assignments and overwhelmingly find them an efficient use of their time, and these opinions are maintained even two years following the course.

  17. Comparative evaluation of microscopy, OptiMAL®and 18S rRNAgene based multiplex PCR for detection of Plasmodium falciparum & Plasmodium vivax from field isolates of Bikaner, India

    Institute of Scientific and Technical Information of China (English)

    Deepak Pakalapati; Jyoti Acharya; Dhanpat Kumar Kochar; Ashis Das; Shilpi Garg; She Middha; Abhishek Kochar; Amit Kumar Subudhi; Boopathi Pon Arunachalam; Sanjay Kumar Kochar; Vishal Saxena; Pareek RP

    2013-01-01

    Objective: To evaluate microscopy, OptiMAL®and multiplex PCR for the identification of Plasmodium falciparum (P. falciparum) and Plasmodium vivax (P. vivax) from the field isolates of Bikaner, Rajasthan (Northwest India). Methods: In this study, a multiplex PCR (P. falciparum and P. vivax) was further developed with the incorporation of Plasmodium malariae (P. malariae) specific primer and also a positive control. The performance of microscopy, plasmodium lactate dehydrogenase (pLDH) based malaria rapid diagnostic test OptiMAL®and 18S rRNA gene based multiplex PCR for the diagnosis of P. falciparum and P. vivax was compared. Results: The three species multiplex PCR (P. falciparum, P. vivax and P. malariae) with an inbuilt positive control was developed and evaluated. In comparison with multiplex PCR, which showed the sensitivity and specificity of 99.36% (95% CI, 98.11%-100.00%) and 100.00% (95% CI, 100.00%-100.00%), the sensitivity and specificity of microscopy was 90.44% (95% CI, 88.84%-95.04%) and 99.22% (95%CI, 97.71%-100.00%), and OptiMAL®was 93.58% (95% CI, 89.75%-97.42%) and 97.69% (95% CI, 95.10%-100.00%). The efficiencies were 99.65%, 95.10% and 95.45% for multiplex PCR, microscopy and OptiMAL®, respectively. Conclusions: Our results raise concerns over the overall sensitivities of microscopy and OptiMAL®, when compared to the multiplex PCR and thus stress the need for new molecular interventions in the accurate detection of the malarial parasites. This further highlights the fact that further developments are needed to improve the performance of rapid diagnostic tests at field level.

  18. Perceived Benefits of Pre-Clinical Simulation-based Training on Clinical Learning Outcomes among Omani Undergraduate Nursing Students

    Directory of Open Access Journals (Sweden)

    Girija Madhavanprabhakaran

    2015-01-01

    Full Text Available Objectives: This study aimed to explore the benefits perceived by Omani undergraduate maternity nursing students regarding the effect of pre-clinical simulation-based training (PSBT on clinical learning outcomes. Methods: This non-experimental quantitative survey was conducted between August and December 2012 among third-year baccalaureate nursing students at Sultan Qaboos University in Muscat, Oman. Voluntary participants were exposed to faculty-guided PSBT sessions using low- and medium-fidelity manikins, standardised scenarios and skill checklists on antenatal, intranatal, postnatal and newborn care and assessment. Participants answered a purposely designed self-administered questionnaire on the benefits of PSBT in enhancing learning outcomes. Items were categorised into six subscales: knowledge, skills, patient safety, academic safety, confidence and satisfaction. Scores were rated on a four-point Likert scale. Results: Of the 57 participants, the majority (95.2% agreed that PSBT enhanced their knowledge. Most students (94.3% felt that their patient safety practices improved and 86.5% rated PSBT as beneficial for enhancing skill competencies. All male students and 97% of the female students agreed that PSBT enhanced their confidence in the safe holding of newborns. Moreover, 93% of participants were satisfied with PSBT. Conclusion: Omani undergraduate nursing students perceived that PSBT enhanced their knowledge, skills, patient safety practices and confidence levels in providing maternity care. These findings support the use of simulation training as a strategy to facilitate clinical learning outcomes in future nursing courses in Oman, although further research is needed to explore the objective impact of PSBT on learning outcomes.

  19. Medical imaging in clinical applications algorithmic and computer-based approaches

    CERN Document Server

    Bhateja, Vikrant; Hassanien, Aboul

    2016-01-01

    This volume comprises of 21 selected chapters, including two overview chapters devoted to abdominal imaging in clinical applications supported computer aided diagnosis approaches as well as different techniques for solving the pectoral muscle extraction problem in the preprocessing part of the CAD systems for detecting breast cancer in its early stage using digital mammograms. The aim of this book is to stimulate further research in medical imaging applications based algorithmic and computer based approaches and utilize them in real-world clinical applications. The book is divided into four parts, Part-I: Clinical Applications of Medical Imaging, Part-II: Classification and clustering, Part-III: Computer Aided Diagnosis (CAD) Tools and Case Studies and Part-IV: Bio-inspiring based Computer Aided diagnosis techniques. .

  20. Clinical variability in dystrophic epidermolysis bullosa and findings with scanning electron microscopy Variabilidade clínica em epidermólise bolhosa distrófica e achados de microscopia eletrônica de varredura

    Directory of Open Access Journals (Sweden)

    Hiram Larangeira de Almeida Jr

    2012-02-01

    Full Text Available In dystrophic epidermolysis bullosa, the genetic defect of anchoring fibrils leads to cleavage beneath the basement membrane and its consequent loss. A 46 year-old female patient presented blisters with a pretibial distribution associated with nail dystrophy. Her two children had hyponychia and anonychia, which affected all toe nails and the thumb, forefinger and middle finger. DNA sequencing identified in exon 75 of COL7A1 gene a pathologic mutation: c.6235G>A (p.Gly2079Arg. Immunomapping of a blister demonstrated collagen IV (basal membrane in the blister roof and collagen VII in its floor, confirming dystrophic epidermolysis bullosa. Scanning electron microscopy of an inverted blister showed net-forming collagen attached to the blister roof . The variability found in this family has already been reported and confirms, on a clinical basis, the nail subtype as a dystrophic variant.Na epidermólise bolhosa distrófica, o defeito genético das fibrilas de ancoragem leva à clivagem abaixo da membrana basal com sua consequente perda. Uma paciente de 46 anos apresentava bolhas pré-tibiais associadas à distrofia ungueal. Seus dois filhos apresentavam hipo e anoníquia, afetando todas as unhas dos pododáctilos e dos primeiros, segundos e terceiros quirodáctilos. O sequenciamento de DNA identificou no exon 75 do gene COL7A1 uma mutação patológica: c.6235G>A (p.Gly2079Arg. O imunomapeamento identificou o colágeno IV no teto e colágeno VII no assoalho de uma bolha , confirmando o diagnóstico de epidermólise bolhosa distrófica. A microscopia eletrônica de varredura de um teto invertido de bolha demonstrou rede de colágeno aderida ao mesmo. A variabilidade clínica encontrada nessa família já foi escrita e confirma, que o subtipo ungueal das epidermólises bolhosas é uma forma distrófica.

  1. Polarized Light Microscopy

    Science.gov (United States)

    Frandsen, Athela F.

    2016-01-01

    Polarized light microscopy (PLM) is a technique which employs the use of polarizing filters to obtain substantial optical property information about the material which is being observed. This information can be combined with other microscopy techniques to confirm or elucidate the identity of an unknown material, determine whether a particular contaminant is present (as with asbestos analysis), or to provide important information that can be used to refine a manufacturing or chemical process. PLM was the major microscopy technique in use for identification of materials for nearly a century since its introduction in 1834 by William Fox Talbot, as other techniques such as SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Infrared spectroscopy), XPD (X-ray Powder Diffraction), and TEM (Transmission Electron Microscopy) had not yet been developed. Today, it is still the only technique approved by the Environmental Protection Agency (EPA) for asbestos analysis, and is often the technique first applied for identification of unknown materials. PLM uses different configurations in order to determine different material properties. With each configuration additional clues can be gathered, leading to a conclusion of material identity. With no polarizing filter, the microscope can be used just as a stereo optical microscope, and view qualities such as morphology, size, and number of phases. With a single polarizing filter (single polars), additional properties can be established, such as pleochroism, individual refractive indices, and dispersion staining. With two polarizing filters (crossed polars), even more can be deduced: isotropy vs. anisotropy, extinction angle, birefringence/degree of birefringence, sign of elongation, and anomalous polarization colors, among others. With the use of PLM many of these properties can be determined in a matter of seconds, even for those who are not highly trained. McCrone, a leader in the field of polarized light microscopy, often

  2. Combining fluorescence and bioluminescence microscopy.

    Science.gov (United States)

    Goda, Kazuhito; Hatta-Ohashi, Yoko; Akiyoshi, Ryutaro; Sugiyama, Takashi; Sakai, Ikuko; Takahashi, Takeo; Suzuki, Hirobumi

    2015-08-01

    Bioluminescence microscopy has revealed that gene expression in individual cells can respond differently to the same stimulus. To understand this phenomenon, it is important to sequentially observe the series of events from cellular signal transduction to gene expression regulated by specific transcription factors derived from signaling cascades in individual cells. However, these processes have been separately analyzed with fluorescence and bioluminescence microscopy. Furthermore, in culture medium, the background fluorescence of luciferin-a substrate of luciferase in promoter assays of gene expression in cultured cells-confounds the simultaneous observation of fluorescence and bioluminescence. Therefore, we optimized conditions for optical filter sets based on spectral properties and the luciferin concentration based on cell permeability for fluorescence observation combined with bioluminescence microscopy. An excitation and emission filter set (492-506 nm and 524-578 nm) was suitable for green fluorescent protein and yellow fluorescent protein imaging of cells, and >100 μM luciferin was acceptable in culture medium based on kinetic constants and the estimated intracellular concentration. Using these parameters, we present an example of sequential fluorescence and bioluminescence microscopic observation of signal transduction (translocation of protein kinase C alpha from the cytoplasm to the plasma membrane) coupled with activation of gene expression by nuclear factor of kappa light polypeptide B in individual cells and show that the gene expression response is not completely concordant with upstream signaling following stimulation with phorbol-12-myristate-13-acetate. Our technique is a powerful imaging tool for analysis of heterogeneous gene expression together with upstream signaling in live single cells.

  3. Clinical Study on the Visceral Differentiation-Based Acupuncture Therapy for Insomnia

    Institute of Scientific and Technical Information of China (English)

    LING Li; JIANG Xin-mei; XUE Jin-wei; WANG Miao; KE Rui

    2008-01-01

    objective;To investigate the clinical effects of acupuncture for insomnia on the basis of visceral differentiation.Methods;Seventy cases of insomnia were randomly divided into a treatment group and a control group,The former was treated by acupuncture based on visceral differentiation and the latter by the routine acupuncture therapy.Results;The clinical effcts were significantly better in the treatment group than that of the control group(P<0.05).Conclusion;The visceral difrerentiation-based acupuncture therapy may enhance the therapeutic effects for insomnia patients.

  4. NMR-based metabolomics of prostate cancer: a protagonist in clinical diagnostics.

    Science.gov (United States)

    Kumar, Deepak; Gupta, Ashish; Nath, Kavindra

    2016-06-01

    Advances in the application of NMR spectroscopy-based metabolomic profiling of prostate cancer comprises a potential tactic for understanding the impaired biochemical pathways arising due to a disease evolvement and progression. This technique involves qualitative and quantitative estimation of plethora of small molecular weight metabolites of body fluids or tissues using state-of-the-art chemometric methods delivering an important platform for translational research from basic to clinical, to reveal the pathophysiological snapshot in a single step. This review summarizes the present arrays and recent advancements in NMR-based metabolomics and a glimpse of currently used medical imaging tactics, with their role in clinical diagnosis of prostate cancer.

  5. Twin-Photon Confocal Microscopy

    CERN Document Server

    Simon, D S

    2010-01-01

    A recently introduced two-channel confocal microscope with correlated detection promises up to 50% improvement in transverse spatial resolution [Simon, Sergienko, Optics Express {\\bf 18}, 9765 (2010)]. Here we move further by introducing a triple-confocal correlated microscope, exploiting the correlations present in optical parametric amplifiers. It is based on tight focusing of pump radiation onto a thin sample positioned in front of a nonlinear crystal, followed by coincidence detection of signal and idler photons, each focused onto a pinhole. This approach offers further resolution enhancement in microscopy.

  6. Visual-servoing optical microscopy

    Science.gov (United States)

    Callahan, Daniel E.; Parvin, Bahram

    2009-06-09

    The present invention provides methods and devices for the knowledge-based discovery and optimization of differences between cell types. In particular, the present invention provides visual servoing optical microscopy, as well as analysis methods. The present invention provides means for the close monitoring of hundreds of individual, living cells over time: quantification of dynamic physiological responses in multiple channels; real-time digital image segmentation and analysis; intelligent, repetitive computer-applied cell stress and cell stimulation; and the ability to return to the same field of cells for long-term studies and observation. The present invention further provides means to optimize culture conditions for specific subpopulations of cells.

  7. Data and image transfer using mobile phones to strengthen microscopy-based diagnostic services in low and middle income country laboratories.

    Directory of Open Access Journals (Sweden)

    Coosje J Tuijn

    Full Text Available BACKGROUND: The emerging market of mobile phone technology and its use in the health sector is rapidly expanding and connecting even the most remote areas of world. Distributing diagnostic images over the mobile network for knowledge sharing, feedback or quality control is a logical innovation. OBJECTIVE: To determine the feasibility of using mobile phones for capturing microscopy images and transferring these to a central database for assessment, feedback and educational purposes. METHODS: A feasibility study was carried out in Uganda. Images of microscopy samples were taken using a prototype connector that could fix a variety of mobile phones to a microscope. An Information Technology (IT platform was set up for data transfer from a mobile phone to a website, including feedback by text messaging to the end user. RESULTS: Clear images were captured using mobile phone cameras of 2 megapixels (MP up to 5MP. Images were sent by mobile Internet to a website where they were visualized and feedback could be provided to the sender by means of text message. CONCLUSION: The process of capturing microscopy images on mobile phones, relaying them to a central review website and feeding back to the sender is feasible and of potential benefit in resource poor settings. Even though the system needs further optimization, it became evident from discussions with stakeholders that there is a demand for this type of technology.

  8. Clinical-decision support based on medical literature: A complex network approach

    Science.gov (United States)

    Jiang, Jingchi; Zheng, Jichuan; Zhao, Chao; Su, Jia; Guan, Yi; Yu, Qiubin

    2016-10-01

    In making clinical decisions, clinicians often review medical literature to ensure the reliability of diagnosis, test, and treatment because the medical literature can answer clinical questions and assist clinicians making clinical decisions. Therefore, finding the appropriate literature is a critical problem for clinical-decision support (CDS). First, the present study employs search engines to retrieve relevant literature about patient records. However, the result of the traditional method is usually unsatisfactory. To improve the relevance of the retrieval result, a medical literature network (MLN) based on these retrieved papers is constructed. Then, we show that this MLN has small-world and scale-free properties of a complex network. According to the structural characteristics of the MLN, we adopt two methods to further identify the potential relevant literature in addition to the retrieved literature. By integrating these potential papers into the MLN, a more comprehensive MLN is built to answer the question of actual patient records. Furthermore, we propose a re-ranking model to sort all papers by relevance. We experimentally find that the re-ranking model can improve the normalized discounted cumulative gain of the results. As participants of the Text Retrieval Conference 2015, our clinical-decision method based on the MLN also yields higher scores than the medians in most topics and achieves the best scores for topics: #11 and #12. These research results indicate that our study can be used to effectively assist clinicians in making clinical decisions, and the MLN can facilitate the investigation of CDS.

  9. Clinical pharmacokinetic/pharmacodynamic and physiologically based pharmacokinetic modeling in new drug development: the capecitabine experience.

    Science.gov (United States)

    Blesch, Karen S; Gieschke, Ronald; Tsukamoto, Yuko; Reigner, Bruno G; Burger, Hans U; Steimer, Jean-Louis

    2003-05-01

    Preclinical studies, along with Phase I, II, and III clinical trials demonstrate the pharmacokinetics, pharmacodynamics, safety and efficacy of a new drug under well controlled circumstances in relatively homogeneous populations. However, these types of studies generally do not answer important questions about variability in specific factors that predict pharmacokinetic and pharmacodynamic (PKPD) activity, in turn affecting safety and efficacy. Semi-physiological and clinical PKPD modeling and simulation offer the possibility of utilizing data obtained in the laboratory and the clinic to make accurate characterizations and predictions of PKPD activity in the target population, based on variability in predictive factors. Capecitabine is an orally administered pro-drug of 5-fluorouracil (5-FU), designed to exploit tissue-specific differences in metabolic enzyme activities in order to enhance efficacy and safety. It undergoes extensive metabolism in multiple physiologic compartments, and presents particular challenges for predicting pharmacokinetic and pharmacodynamic activity in humans. Clinical and physiologically based pharmacokinetic (PBPK) and pharmacodynamic models were developed to characterize the activity of capecitabine and its metabolites, and the clinical consequences under varying physiological conditions such as creatinine clearance or activity of key metabolic enzymes. The results of the modeling investigations were consistent with capecitabine's rational design as a triple pro-drug of 5-FU. This paper reviews and discusses the PKPD and PBPK modeling approaches used in capecitabine development to provide a more thorough understanding of what the key predictors of its PBPK activity are, and how variability in these predictors may affect its PKPD, and ultimately, clinical outcomes.

  10. Quantitative Susceptibility Mapping-Based Microscopy of Magnetic Resonance Venography (QSM-mMRV for In Vivo Morphologically and Functionally Assessing Cerebromicrovasculature in Rat Stroke Model.

    Directory of Open Access Journals (Sweden)

    Meng-Chi Hsieh

    Full Text Available Abnormal cerebral oxygenation and vessel structure is a crucial feature of stroke. An imaging method with structural and functional information is necessary for diagnosis of stroke. This study applies QSM-mMRV (quantitative susceptibility mapping-based microscopic magnetic resonance venography for noninvasively detecting small cerebral venous vessels in rat stroke model. First, susceptibility mapping is optimized and calculated from magnetic resonance (MR phase images of a rat brain. Subsequently, QSM-mMRV is used to simultaneously provide information on microvascular architecture and venous oxygen saturation (SvO2, both of which can be used to evaluate the physiological and functional characteristics of microvascular changes for longitudinally monitoring and therapeutically evaluating a disease model. Morphologically, the quantification of vessel sizes using QSM-mMRV was 30% smaller than that of susceptibility-weighted imaging (SWI, which eliminated the overestimation of conventional SWI. Functionally, QSM-mMRV estimated an average SvO2 ranging from 73% to 85% for healthy rats. Finally, we also applied QSM to monitor the revascularization of post-stroke vessels from 3 to 10 days after reperfusion. QSM estimations of SvO2 were comparable to those calculated using the pulse oximeter standard metric. We conclude that QSM-mMRV is useful for longitudinally monitoring blood oxygen and might become clinically useful for assessing cerebrovascular diseases.

  11. Developing a competency-based educational structure within clinical and translational science.

    Science.gov (United States)

    Dilmore, Terri Collin; Moore, Debra W; Bjork, Zuleikha

    2013-04-01

    In the emerging field of clinical and translational science (CTS), where researchers use both basic and clinical science research methodologies to move discoveries to clinical practice, establishing standards of competence is essential for preparing physician-scientists for the profession and for defining the field. The diversity of skills needed to execute quality research within the field of CTS has heightened the importance of an educational process that requires learners to demonstrate competence. Particularly within the more applied clinical science disciplines where there is a multi- or interdisciplinary approach to conducting research, defining and articulating the unique role and associated competencies of a physician-scientist is necessary. This paper describes a systematic process for developing a competency-based educational framework within a CTS graduate program at one institution.

  12. Training-Based Interventions in Motor Rehabilitation after Stroke: Theoretical and Clinical Considerations

    Directory of Open Access Journals (Sweden)

    Annette Sterr

    2004-01-01

    Full Text Available Basic neuroscience research on brain plasticity, motor learning and recovery has stimulated new concepts in neurological rehabilitation. Combined with the development of set methodological standards in clinical outcome research, these findings have led to a double-paradigm shift in motor rehabilitation: (a the move towards evidence-based procedures for the assessment of clinical outcome & the employment of disablement models to anchor outcome parameters, and (b the introduction of practice-based concepts that are derived from testable models that specify treatment mechanisms. In this context, constraint-induced movement therapy (CIT has played a catalytic role in taking motor rehabilitation forward into the scientific arena. As a theoretically founded and hypothesis-driven intervention, CIT research focuses on two main issues. The first issue is the assessment of long-term clinical benefits in an increasing range of patient groups, and the second issue is the investigation of neuronal and behavioural treatment mechanisms and their interactive contribution to treatment success. These studies are mainly conducted in the research environment and will eventually lead to increased treatment benefits for patients in standard health care. However, gradual but presumably more immediate benefits for patients may be achieved by introducing and testing derivates of the CIT concept that are more compatible with current clinical practice. Here, we summarize the theoretical and empirical issues related to the translation of research-based CIT work into the clinical context of standard health care.

  13. Comparison of multi-mode parallel detection microscopy methods

    Science.gov (United States)

    Zhu, Dazhao; Fang, Yue; Chen, Youhua; Hussain, Anwar; Kuang, Cuifang; Ding, Zhihua; Liu, Xu

    2017-03-01

    Four microscopy resolution enhancement methods based on parallel detection were investigated in this study: confocal microscopy with four pinhole sizes, fluorescence emission difference microscopy (FED) based on parallel detection, Airyscan microscopy, and virtual k-vector modulation optical microscopy (Vikmom). These methods use different algorithms to process parallel detection data and achieve resolution improvement. We investigated these methods first by performing simulations and then experimentally. In this report, the basic theories of these methods are briefly introduced. Then, analyses and comparisons of their imaging performances, especially in terms of resolution improvement, imaging speed, and signal-to-noise ratio, are presented. Finally, the results of our comparative study are summarized.

  14. Final-Year Students' and Clinical instructors' Experience of Workplace-Based Assessments Used in a Small-Animal Primary-Veterinary-Care Clinical Rotation.

    Science.gov (United States)

    Weijs, Cynthia A; Coe, Jason B; Hecker, Kent G

    2015-01-01

    Final-year veterinary students must meet baseline clinical competency upon completion of their training for entry to practice. Workplace-based assessments (WBAs), widely used in human medical training to assess post-graduate students' professionalism and clinical performance, have recently been adopted in undergraduate veterinary clinical teaching environments. WBAs should support veterinary trainees' learning in a clinical teaching environment, though utility of WBAs within veterinary education may differ from that in medical training due to differences in context and in learners' stage of clinical development. We conducted focus groups with final-year veterinary students and clinical instructors following the implementation of three WBAs (Direct Observation of Procedural Skills [DOPS], the Mini-Clinical evaluation exercise [Mini-CEX], and the In-Training Evaluation Report [ITER]) during a small-animal primary-veterinary-care rotation. Students and clinical instructors viewed the DOPS and Mini-CEX as feasible and valuable learning and assessment tools that offered an overall opportunity for timely in-the-moment feedback. Instructors viewed the ITER as less feasible in the context of a service-oriented veterinary clinical teaching environment. Students believed the ITER had potential to be informative, although in its existing application the ITER had limited utility due to time constraints on instructors that prevented them from providing students with individualized and specific feedback. In service-oriented veterinary clinical teaching environments, successful implementation of WBAs requires balancing provision of feedback to students, time demands on clinical instructors, and flexibility of assessment tools.

  15. Mindfulness-based stress reduction for comorbid anxiety and depression: case report and clinical considerations.

    Science.gov (United States)

    Hazlett-Stevens, Holly

    2012-11-01

    Growing research literature has documented the effectiveness of mindfulness-based interventions for anxiety and depressive disorders. Mindfulness-based stress reduction (MBSR) teaches a series of mindfulness meditation and yoga practices, delivered in a group format during eight weekly sessions plus one full-day session. This case report demonstrates how MBSR was associated with dramatic clinical improvement of an individual with symptoms of panic, generalized anxiety, and depression. Scores on clinical assessment measures suggested clinically severe levels of anxious arousal, generalized anxiety, worry, fear of negative evaluation, and depression at the beginning of the intervention. The scores on all these measures fell well within normal limits 7 weeks later at the end of the intervention, and no remaining symptoms were reported afterward. Increased life satisfaction and quality of life were documented as well. This case illustrates the potential benefit of MBSR as an alternative or adjunctive treatment for comorbid anxiety and depressive disorder symptoms.

  16. [Exercise is medicine: development and evidence-based practice in clinical exercise physiology].

    Science.gov (United States)

    Zhou, Shi

    2014-08-01

    It has been well established that appropriate physical activity and exercise play an important role in promotion of health and fitness, prevention of disease and treatment and rehabilitation of health conditions. However, practice based on scientific evidence, in respect of the role and effectiveness of exercise interventions in prevention and treatment of diseases, has only been promoted and implemented in the fields of clinical exercise physiology, public health and medicine in recent years. This brief review provides an introduction of the concept of "Exercise is Medicine", the development and evidence-based practice in Clinical Exercise Physiology, and the role and training of Clinical Exercise Physiologist in the health care system of some other countries.

  17. Developing evidence-based dentistry skills: how to interpret randomized clinical trials and systematic reviews.

    Science.gov (United States)

    Kiriakou, Juliana; Pandis, Nikolaos; Madianos, Phoebus; Polychronopoulou, Argy

    2014-10-30

    Decision-making based on reliable evidence is more likely to lead to effective and efficient treatments. Evidence-based dentistry was developed, similarly to evidence-based medicine, to help clinicians apply current and valid research findings into their own clinical practice. Interpreting and appraising the literature is fundamental and involves the development of evidence-based dentistry (EBD) skills. Systematic reviews (SRs) of randomized controlled trials (RCTs) are considered to be evidence of the highest level in evaluating the effectiveness of interventions. Furthermore, the assessment of the report of a RCT, as well as a SR, can lead to an estimation of how the study was designed and conducted.

  18. Association of School-Based Influenza Vaccination Clinics and School Absenteeism--Arkansas, 2012-2013

    Science.gov (United States)

    Gicquelais, Rachel E.; Safi, Haytham; Butler, Sandra; Smith, Nathaniel; Haselow, Dirk T.

    2016-01-01

    Background: Influenza is a major cause of seasonal viral respiratory illness among school-aged children. Accordingly, the Arkansas Department of Health (ADH) coordinates >800 school-based influenza immunization clinics before each influenza season. We quantified the relationship between student influenza vaccination in Arkansas public schools…

  19. Conveying clinical reasoning based on visual observation via eye-movement modelling examples

    NARCIS (Netherlands)

    Jarodzka, Halszka; Balslev, Thomas; Holmqvist, Kenneth; Nyström, Marcus; Scheiter, Katharina; Gerjets, Peter; Eika, Berit

    2012-01-01

    Jarodzka, H., Balslev, T., Holmqvist, K., Nyström, M., Scheiter, K., Gerjets, P., & Eika, B. (2012). Conveying clinical reasoning based on visual observation via eye-movement modelling examples. Instructional Science, 40(5), 813-827. doi:10.1007/s11251-012-9218-5

  20. Automatic Domain Adaptation of Word Sense Disambiguation Based on Sublanguage Semantic Schemata Applied to Clinical Narrative

    Science.gov (United States)

    Patterson, Olga

    2012-01-01

    Domain adaptation of natural language processing systems is challenging because it requires human expertise. While manual effort is effective in creating a high quality knowledge base, it is expensive and time consuming. Clinical text adds another layer of complexity to the task due to privacy and confidentiality restrictions that hinder the…