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Sample records for detecting focused ultrasound-induced

  1. Photoacoustic detection and optical spectroscopy of high-intensity focused ultrasound-induced thermal lesions in biologic tissue

    SciTech Connect

    Alhamami, Mosa; Kolios, Michael C.; Tavakkoli, Jahan

    2014-05-15

    Purpose: The aims of this study are: (a) to investigate the capability of photoacoustic (PA) method in detecting high-intensity focused ultrasound (HIFU) treatments in muscle tissuesin vitro; and (b) to determine the optical properties of HIFU-treated and native tissues in order to assist in the interpretation of the observed contrast in PA detection of HIFU treatments. Methods: A single-element, spherically concaved HIFU transducer with a centre frequency of 1 MHz was utilized to create thermal lesions in chicken breast tissuesin vitro. To investigate the detectability of HIFU treatments photoacoustically, PA detection was performed at 720 and 845 nm on seven HIFU-treated tissue samples. Within each tissue sample, PA signals were acquired from 22 locations equally divided between two regions of interest within two volumes in tissue – a HIFU-treated volume and an untreated volume. Optical spectroscopy was then carried out on 10 HIFU-treated chicken breast specimens in the wavelength range of 500–900 nm, in 1-nm increments, using a spectrophotometer with an integrating sphere attachment. The authors’ optical spectroscopy raw data (total transmittance and diffuse reflectance) were used to obtain the optical absorption and reduced scattering coefficients of HIFU-induced thermal lesions and native tissues by employing the inverse adding-doubling method. The aforementioned interaction coefficients were subsequently used to calculate the effective attenuation coefficient and light penetration depth of HIFU-treated and native tissues in the wavelength range of 500–900 nm. Results: HIFU-treated tissues produced greater PA signals than native tissues at 720 and 845 nm. At 720 nm, the averaged ratio of the peak-to-peak PA signal amplitude of HIFU-treated tissue to that of native tissue was 3.68 ± 0.25 (mean ± standard error of the mean). At 845 nm, the averaged ratio of the peak-to-peak PA signal amplitude of HIFU-treated tissue to that of native tissue was 3.75

  2. Contrast-Enhanced Ultrasound Imaging for the Detection of Focused Ultrasound-Induced Blood-Brain Barrier Opening

    PubMed Central

    Fan, Ching-Hsiang; Lin, Wun-Hao; Ting, Chien-Yu; Chai, Wen-Yen; Yen, Tzu-Chen; Liu, Hao-Li; Yeh, Chih-Kuang

    2014-01-01

    The blood-brain barrier (BBB) can be transiently and locally opened by focused ultrasound (FUS) in the presence of microbubbles (MBs). Various imaging modalities and contrast agents have been used to monitor this process. Unfortunately, direct ultrasound imaging of BBB opening with MBs as contrast agent is not feasible, due to the inability of MBs to penetrate brain parenchyma. However, FUS-induced BBB opening is accompanied by changes in blood flow and perfusion, suggesting the possibility of perfusion-based ultrasound imaging. Here we evaluated the use of MB destruction-replenishment, which was originally developed for analysis of ultrasound perfusion kinetics, for verifying and quantifying FUS-induced BBB opening. MBs were intravenously injected and the BBB was disrupted by 2 MHz FUS with burst-tone exposure at 0.5-0.7 MPa. A perfusion kinetic map was estimated by MB destruction-replenishment time-intensity curve analysis. Our results showed that the scale and distribution of FUS-induced BBB opening could be determined at high resolution by ultrasound perfusion kinetic analysis. The accuracy and sensitivity of this approach was validated by dynamic contrast-enhanced MRI. Our successful demonstration of ultrasound imaging to monitor FUS-induced BBB opening provides a new approach to assess FUS-dependent brain drug delivery, with the benefit of high temporal resolution and convenient integration with the FUS device. PMID:25161701

  3. High Intensity Focused Ultrasound induced Gene Activation in Solid Tumors

    NASA Astrophysics Data System (ADS)

    Liu, Yunbo; Kon, Takashi; Li, Chuanyuan; Zhong, Pei

    2006-05-01

    In this work, the feasibility of using high intensity focused ultrasound (HIFU) to activate trans-gene expression in a mouse tumor model was investigated. 4T1 cancer cells were implanted subcutaneously in the hind limbs of Balb/C mice and adenovirus luciferase gene vectors under the control of heat shock protein 70B promoter (Adeno-hsp70B-Luc) were injected intratumoraly for gene transfection. One day following the virus injection, the transfected tumors were heated to a peak temperature of 55, 65, 75, and 85°C, respectively, in 10s at multiple sites around the center of the tumor using a HIFU transducer operated at either 1.1-MHz (fundamental) or 3.3-MHz (3rd harmonic) frequency. Inducible luciferase gene expression was found to vary from 15-fold to 120-fold of the control group following 1.1-MHz HIFU exposure. The maximum gene activation was produced at a peak temperature of 65˜75°C one day following HIFU exposure and decayed gradually to baseline level within 7 days. The inducible gene activation produced by 3.3-MHz HIFU exposure (75°C-10s) was found to be comparable to that produced by hyperthermia (42°C-30min). Altogether, these results demonstrate the feasibility of using HIFU as a simple and versatile physical means to regulate trans-gene expression in vivo. This unique feature may be explored in the future for a synergistic combination of HIFU-induced thermal ablation with heat-induced gene therapy for improved cancer therapy.

  4. Quasi-static elastography and its application in investigation of focused ultrasound induced tissue lesions

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Ling, Tao; Shen, Yong; Wang, Yan; Zheng, Hairong; Li, Faqi

    2012-10-01

    Monitoring of Focused Ultrasound (FUS) therapy has always been a key factor for a successful therapy. Although B-mode ultrasound has long been used for monitoring FUS therapy, the gray scale changes can not precisely reflect the lesion formation inside the tissue, while MR thermometry is considered to be too expensive. In this study, elastography had been performed using a commercial ultrasound system to investigate lesions produced by FUS irradiation in vitro. Several motion detection algorithms had been performed to improve the motion detection accuracy in the elastography. The effects of different algorithms on the motion detection accuracy were compared. Experimental results on the FUS induced lesion in swine muscle were introduced. The results indicated that lesions induced by small dosage of FUS inside the tissue can be successfully detected, which has a profound clinical meaning for the monitoring of FUS therapy.

  5. Low Dose Focused Ultrasound Induces Enhanced Tumor Accumulation of Natural Killer Cells

    PubMed Central

    Sta Maria, Naomi S.; Barnes, Samuel R.; Weist, Michael R.; Colcher, David; Raubitschek, Andrew A.; Jacobs, Russell E.

    2015-01-01

    Natural killer (NK) cells play a vital antitumor role as part of the innate immune system. Efficacy of adoptive transfer of NK cells depends on their ability to recognize and target tumors. We investigated whether low dose focused ultrasound with microbubbles (ldbFUS) could facilitate the targeting and accumulation of NK cells in a mouse xenograft of human colorectal adenocarcinoma (carcinoembryonic antigen (CEA)-expressing LS-174T implanted in NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) mice) in the presence of an anti-CEA immunocytokine (ICK), hT84.66/M5A-IL-2 (M5A-IL-2). Human NK cells were labeled with an FDA-approved ultra-small superparamagnetic iron oxide particle, ferumoxytol. Simultaneous with the intravenous injection of microbubbles, focused ultrasound was applied to the tumor. In vivo longitudinal magnetic resonance imaging (MRI) identified enhanced accumulation of NK cells in the ensonified tumor, which was validated by endpoint histology. Significant accumulation of NK cells was observed up to 24 hrs at the tumor site when ensonified with 0.50 MPa peak acoustic pressure ldbFUS, whereas tumors treated with at 0.25 MPa showed no detectable NK cell accumulation. These clinically translatable results show that ldbFUS of the tumor mass can potentiate tumor homing of NK cells that can be evaluated non-invasively using MRI. PMID:26556731

  6. Photoacoustic micro-imaging of focused ultrasound induced blood-brain-barrier opening in a rat model

    NASA Astrophysics Data System (ADS)

    Wang, Po-Hsun; Hsu, Po-Hung; Liu, Hao-Li; Wang, Churng-Ren Chris; Li, Meng-Lin

    2010-02-01

    Blood brain barrier (BBB) prevents most of the drug from transmitting into the brain tissue and decreases the treatment performance for brain disease. One of the methods to overcome the difficulty of drug delivery is to locally increase the permeability of BBB with high-intensity focused ultrasound. In this study, we have investigated the feasibility of photoacoustic microscopy of focused-ultrasound induced BBB opening in a rat model in vivo with gold nanorods (AuNRs) as a contrast agent. This study takes advantage of the strong near-infrared absorption of AuNRs and their extravasation tendency from BBB opening foci due to their nano-scale size. Before the experiments, craniotomy was performed on rats to provide a path for focused ultrasound beam. Localized BBB opening at the depth of about 3 mm from left cortex of rat brains was achieved by delivering 1.5 MHz focused ultrasound energy into brain tissue in the presence of microbubbles. PEGylated AuNRs with a peak optical absorption at ~800 nm were then intravenously administered. Pre-scan prior to BBB disruption and AuNR injection was taken to mark the signal background. After injection, the distribution of AuNRs in rat brains was monitored up to 2 hours. Experimental results show that imaging AuNRs reveals BBB disruption area in left brains while there are no changes observed in the right brains. From our results, photoacoustic imaging plus AuNRs shows the promise as a novel monitoring strategy in identifying the location and variation of focused-ultrasound BBB-opening in a rat model.

  7. Focused Ultrasound-Induced Neurogenesis Requires an Increase in Blood-Brain Barrier Permeability

    PubMed Central

    Mooney, Skyler J.; Shah, Kairavi; Yeung, Sharon; Burgess, Alison; Aubert, Isabelle; Hynynen, Kullervo

    2016-01-01

    Transcranial focused ultrasound technology used to transiently open the blood-brain barrier, is capable of stimulating hippocampal neurogenesis; however, it is not yet known what aspects of the treatment are necessary for enhanced neurogenesis to occur. The present study set out to determine whether the opening of blood-brain barrier, the specific pressure amplitudes of focused ultrasound, and/or the intravenous administration of microbubbles (phospholipid microspheres) are necessary for the enhancement of neurogenesis. Specifically, mice were exposed to burst (10ms, 1Hz burst repetition frequency) focused ultrasound at the frequency of 1.68MHz and with 0.39, 0.78, 1.56 and 3.0MPa pressure amplitudes. These treatments were also conducted with or without microbubbles, at 0.39 + 0.78MPa or 1.56 + 3.0MPa, respectively. Only focused ultrasound at the ~0.78 MPa pressure amplitude with microbubbles promoted hippocampal neurogenesis and was associated with an increase in blood-brain barrier permeability. These results suggest that focused ultrasound -mediated neurogenesis is dependent upon the opening of the blood-brain barrier. PMID:27459643

  8. Dependence of pulsed focused ultrasound induced thrombolysis on duty cycle and cavitation bubble size distribution.

    PubMed

    Xu, Shanshan; Zong, Yujin; Feng, Yi; Liu, Runna; Liu, Xiaodong; Hu, Yaxin; Han, Shimin; Wan, Mingxi

    2015-01-01

    In this study, we investigated the relationship between the efficiency of pulsed, focused ultrasound (FUS)-induced thrombolysis, the duty cycle (2.3%, 9%, and 18%) and the size distribution of cavitation bubbles. The efficiency of thrombolysis was evaluated through the degree of mechanical fragmentation, namely the number, mass, and size of clot debris particles. First, we found that the total number and mass of clot debris particles were highest when a duty cycle of 9% was used and that the mean diameter of clot debris particles was smallest. Second, we found that the size distribution of cavitation bubbles was mainly centered around the linear resonance radius (2.5μm) of the emission frequency (1.2MHz) of the FUS transducer when a 9% duty cycle was used, while the majority of cavitation bubbles became smaller or larger than the linear resonance radius when a 2.3% or 18% duty cycle was used. In addition, the inertial cavitation dose from the treatment performed at 9% duty cycle was much higher than the dose obtained with the other two duty cycles. The data presented here suggest that there is an optimal duty cycle at which the thrombolysis efficiency and cavitation activity are strongest. They further indicate that using a pulsed FUS may help control the size distribution of cavitation nuclei within an active size range, which we found to be near the linear resonance radius of the emission frequency of the FUS transducer.

  9. Feasibility study on photoacoustic guidance for high-intensity focused ultrasound-induced hemostasis

    NASA Astrophysics Data System (ADS)

    Nguyen, Van Phuc; Kim, Jeehyun; Ha, Kang-lyeol; Oh, Junghwan; Kang, Hyun Wook

    2014-10-01

    The feasibility of photoacoustic imaging (PAI) application was evaluated to map punctured blood vessels thermally treated by high-intensity focused ultrasound (HIFU) for hemostasis. A single-element HIFU transducer with a central frequency of 2.0 MHz, was used to induce thermal hemostasis on the punctured arteries. The HIFU-treated lesion was imaged and localized by high-contrast PAI guidance. The results showed that complete hemostasis was achieved after treatment of the damaged blood vessels within 25 to 52 s at the acoustic intensity of 3600 W/cm2. The coagulation time for the animal artery was ˜20% longer than that of the phantom possibly due to a lower Young's modulus. The reconstructed PA images were able to distinguish the treated area from the surrounding tissue in terms of augmented signal amplitudes (up to three times). Spectroscopic studies demonstrated that the optimal imaging wavelength was found to be 700 nm in order to reconstruct high-contrast photoacoustic images on HIFU-treated lesions. The proposed PAI integrated with HIFU treatment can be a feasible application to obtain safe and rapid hemostasis for acute arterial bleeding.

  10. Modeling of high-intensity focused ultrasound-induced lesions in the presence of cavitation bubbles

    PubMed

    Chavrier; Chapelon; Gelet; Cathignol

    2000-07-01

    The classical "Bio Heat Transfer Equation (BHTE)" model is adapted to take into account the effects of oscillating microbubbles that occur naturally in the tissue during high-intensity focused ultrasound (HIFU) treatment. First, the Gilmore-Akulichev model is used to quantify the acoustic pressure scattered by microbubbles submitted to HIFU. Because this scattered pressure is not monochromatic, the concept of harmonic attenuation is introduced and a global attenuation coefficient is estimated for bubble-filled tissues. The first results show that this global attenuation coefficient varies significantly with respect to several parameters such as the frequency and the density of microbubbles in the medium, but also with respect to the incident acoustic pressure which thus becomes a transcendental function. Under these conditions, a layer-by-layer modeling, in the direction of propagation, is proposed to calculate the ultrasonic beam. Finally, the BHTE is solved and the HIFU-induced lesions are estimated by the calculation of the thermal dose. Using this model, it can be observed first that, when the firing power increases, the lesion develops clearly in the direction of the transducer, with a shape agreeing with in vivo experimentation. Next, it is observed that the lesion can be significantly modified in size and position, if an interface (skin or inner wall) is simulated as a zone with multiple cavitation nuclei. With a firing power increase, it is also shown how a secondary lesion can appear at the interface and how, beyond a certain threshold, this lesion develops at the main lesion expense. Finally, a better in-depth homogeneity of lesions is observed when the acoustic frequency of HIFU is increased.

  11. Detecting hepatic steatosis using ultrasound-induced thermal strain imaging: an ex vivo animal study

    NASA Astrophysics Data System (ADS)

    Mahmoud, Ahmed M.; Ding, Xuan; Dutta, Debaditya; Singh, Vijay P.; Kim, Kang

    2014-02-01

    Hepatic steatosis or fatty liver disease occurs when lipids accumulate within the liver and can lead to steatohepatitis, cirrhosis, liver cancer and eventual liver failure requiring liver transplant. Conventional brightness mode (B-mode) ultrasound (US) is the most common noninvasive diagnostic imaging modality used to diagnose hepatic steatosis in clinics. However, it is mostly subjective or requires a reference organ such as the kidney or spleen with which to compare. This comparison can be problematic when the reference organ is diseased or absent. The current work presents an alternative approach to noninvasively detecting liver fat content using US-induced thermal strain imaging (US-TSI). This technique is based on the difference in the change in the speed of sound as a function of temperature between water- and lipid-based tissues. US-TSI was conducted using two system configurations including a mid-frequency scanner with a single linear array transducer (5-14 MHz) for both imaging and heating and a high-frequency (13-24 MHz) small animal imaging system combined with a separate custom-designed US heating transducer array. Fatty livers (n = 10) with high fat content (45.6 ± 11.7%) from an obese mouse model and control livers (n = 10) with low fat content (4.8 ± 2.9%) from wild-type mice were embedded in gelatin. Then, US imaging was performed before and after US induced heating. Heating time periods of ˜3 s and ˜9.2 s were used for the mid-frequency imaging and high-frequency imaging systems, respectively, to induce temperature changes of approximately 1.5 °C. The apparent echo shifts that were induced as a result of sound speed change were estimated using 2D phase-sensitive speckle tracking. Following US-TSI, histology was performed to stain lipids and measure percentage fat in the mouse livers. Thermal strain measurements in fatty livers (-0.065 ± 0.079%) were significantly (p < 0.05) higher than those measured in control livers (-0.124 ± 0

  12. Feasibility of optoacoustic visualization of high-intensity focused ultrasound-induced thermal lesions in live tissue.

    PubMed

    Chitnis, Parag V; Brecht, Hans-Peter; Su, Richard; Oraevsky, Alexander A

    2010-01-01

    A 3-D optoacoustic imaging system was used to visualize thermal lesions produced in vivo using high-intensity focused ultrasound (HIFU). A 7.5-MHz, surgical, focused transducer with a radius of curvature of 35 mm and an aperture diameter of 23 mm was used to generate HIFU. A pulsed laser, which could operate at 755 nm and 1064 nm, was used to illuminate excised tissue and mice using a bifurcated fiber bundle resulting in two wide beams of light. Tomographic images were obtained while the specimens were rotated within a sphere outlined by a concave arc-shaped array of 64 piezo-composite transducers. These images were then combined to reconstruct 3-D volume images (voxel resolution 0.5 mm), which were acquired before and after HIFU exposure. In vivo optoacoustic images acquired at 1064 nm provided visualization of HIFU lesions. The lesion was indicated by a negative optoacoustic contrast. The molecular nature of such contrast may possibly be associated with reduction of the optical absorption due to reduced concentration of blood, tissue dehydration, denaturation of proteins and porphyrins, and reduction of thermoacoustic efficiency in the thermally treated tissue. These preliminary results demonstrate the potential of optoacoustic imaging to assess and monitor the progress of HIFU therapy. PMID:20459235

  13. Feasibility of optoacoustic visualization of high-intensity focused ultrasound-induced thermal lesions in live tissue

    NASA Astrophysics Data System (ADS)

    Chitnis, Parag V.; Brecht, Hans-Peter; Su, Richard; Oraevsky, Alexander A.

    2010-03-01

    A 3-D optoacoustic imaging system was used to visualize thermal lesions produced in vivo using high-intensity focused ultrasound (HIFU). A 7.5-MHz, surgical, focused transducer with a radius of curvature of 35 mm and an aperture diameter of 23 mm was used to generate HIFU. A pulsed laser, which could operate at 755 nm and 1064 nm, was used to illuminate excised tissue and mice using a bifurcated fiber bundle resulting in two wide beams of light. Tomographic images were obtained while the specimens were rotated within a sphere outlined by a concave arc-shaped array of 64 piezo-composite transducers. These images were then combined to reconstruct 3-D volume images (voxel resolution 0.5 mm), which were acquired before and after HIFU exposure. In vivo optoacoustic images acquired at 1064 nm provided visualization of HIFU lesions. The lesion was indicated by a negative optoacoustic contrast. The molecular nature of such contrast may possibly be associated with reduction of the optical absorption due to reduced concentration of blood, tissue dehydration, denaturation of proteins and porphyrins, and reduction of thermoacoustic efficiency in the thermally treated tissue. These preliminary results demonstrate the potential of optoacoustic imaging to assess and monitor the progress of HIFU therapy.

  14. Nakagami imaging for detecting thermal lesions induced by high-intensity focused ultrasound in tissue.

    PubMed

    Rangraz, Parisa; Behnam, Hamid; Tavakkoli, Jahan

    2014-01-01

    High-intensity focused ultrasound induces focalized tissue coagulation by increasing the tissue temperature in a tight focal region. Several methods have been proposed to monitor high-intensity focused ultrasound-induced thermal lesions. Currently, ultrasound imaging techniques that are clinically used for monitoring high-intensity focused ultrasound treatment are standard pulse-echo B-mode ultrasound imaging, ultrasound temperature estimation, and elastography-based methods. On the contrary, the efficacy of two-dimensional Nakagami parametric imaging based on the distribution of the ultrasound backscattered signals to quantify properties of soft tissue has recently been evaluated. In this study, ultrasound radio frequency echo signals from ex vivo tissue samples were acquired before and after high-intensity focused ultrasound exposures and then their Nakagami parameter and scaling parameter of Nakagami distribution were estimated. These parameters were used to detect high-intensity focused ultrasound-induced thermal lesions. Also, the effects of changing the acoustic power of the high-intensity focused ultrasound transducer on the Nakagami parameters were studied. The results obtained suggest that the Nakagami distribution's scaling and Nakagami parameters can effectively be used to detect high-intensity focused ultrasound-induced thermal lesions in tissue ex vivo. These parameters can also be used to understand the degree of change in tissue caused by high-intensity focused ultrasound exposures, which could be interpreted as a measure of degree of variability in scatterer concentration in various parts of the high-intensity focused ultrasound lesion. PMID:24264647

  15. Permeability assessment of the focused ultrasound-induced blood-brain barrier opening using dynamic contrast-enhanced MRI

    NASA Astrophysics Data System (ADS)

    Vlachos, F.; Tung, Y.-S.; Konofagou, E. E.

    2010-09-01

    Focused ultrasound (FUS) in conjunction with microbubbles has been shown to successfully open the blood-brain barrier (BBB) in the mouse brain. In this study, we compute the BBB permeability after opening in vivo. The spatial permeability of the BBB-opened region was assessed using dynamic contrast-enhanced MRI (DCE-MRI). The DCE-MR images were post-processed using the general kinetic model (GKM) and the reference region model (RRM). Permeability maps were generated and the Ktrans values were calculated for a predefined volume of interest in the sonicated and the control area for each mouse. The results demonstrated that Ktrans in the BBB-opened region (0.02 ± 0.0123 for GKM and 0.03 ± 0.0167 min-1 for RRM) was at least two orders of magnitude higher when compared to the contra-lateral (control) side (0 and 8.5 × 10-4 ± 12 × 10-4 min-1, respectively). The permeability values obtained with the two models showed statistically significant agreement and excellent correlation (R2 = 0.97). At histological examination, it was concluded that no macroscopic damage was induced. This study thus constitutes the first permeability assessment of FUS-induced BBB opening using DCE-MRI, supporting the fact that the aforementioned technique may constitute a safe, non-invasive and efficacious drug delivery method.

  16. Microbubble-Size Dependence of Focused Ultrasound-Induced Blood–Brain Barrier Opening in Mice In Vivo

    PubMed Central

    Choi, James J.; Feshitan, Jameel A.; Baseri, Babak; Wang, Shougang; Tung, Yao-Sheng; Borden, Mark A.; Konofagou, Elisa E.

    2014-01-01

    The therapeutic efficacy of neurological agents is severely limited, because large compounds do not cross the blood–brain barrier (BBB). Focused ultrasound (FUS) sonication in the presence of microbubbles has been shown to temporarily open the BBB, allowing systemically administered agents into the brain. Until now, polydispersed microbubbles (1–10 μm in diameter) were used, and, therefore, the bubble sizes better suited for inducing the opening remain unknown. Here, the FUS-induced BBB opening dependence on microbubble size is investigated. Bubbles at 1–2 and 4–5 μm in diameter were separately size-isolated using differential centrifugation before being systemically administered in mice (n = 28). The BBB opening pressure threshold was identified by varying the peak-rarefactional pressure amplitude. BBB opening was determined by fluorescence enhancement due to systemically administered, fluorescent-tagged, 3-kDa dextran. The identified threshold fell between 0.30 and 0.46 MPa in the case of 1–2 μm bubbles and between 0.15 and 0.30 MPa in the 4–5 μm case. At every pressure studied, the fluorescence was greater with the 4–5 μm than with the 1–2 μm bubbles. At 0.61 MPa, in the 1–2 μm bubble case, the fluorescence amount and area were greater in the thalamus than in the hippocampus. In conclusion, it was determined that the FUS-induced BBB opening was dependent on both the size distribution in the injected microbubble volume and the brain region targeted. PMID:19846365

  17. Overview of ultrasound-induced lung hemorrhage

    NASA Astrophysics Data System (ADS)

    O'Brien, William D.; Simpson, Douglas G.; Frizzell, Leon A.; Oelze, Michael L.; Zachary, James F.

    2003-10-01

    It is well documented that ultrasound-induced lung hemorrhage can occur in mice, rats, rabbits, pigs, and monkeys. Our own experimental studies have focused on mice, rats, and pigs as animal models. The characteristics of the lesions produced in mice, rats and pigs were similar to those described in studies by our research group and others, suggesting a common pathogenesis for the initiation and propagation of the lesions at the macroscopic and microscopic levels. Five experimental in vivo studies have been conducted to evaluate whether cavitation is responsible for ultrasound-induced lung hemorrhage. The studies evaluated the dependencies of hydrostatic pressure, frequency, pulse polarity, contrast agents and lung inflation, and the results of each study appeared inconsistent with the hypothesis that the mechanism for the production of a lung hemorrhage was inertial cavitation. Other dependencies evaluated included beam width, pulse repetition frequency, pulse duration, exposure duration, and animal species and age. The thresholds for producing ultrasound-induced lung hemorrhage, in general, were less than the FDA's regulatory limit of a Mechanical Index (MI) of 1.9. Further, the MI does not appear to provide a risk-based index for lung hemorrhage. [Work supported by NIH Grant No. R01EB02641.

  18. Paramagnetic perfluorocarbon-filled albumin-(Gd-DTPA) microbubbles for the induction of focused-ultrasound-induced blood-brain barrier opening and concurrent MR and ultrasound imaging.

    PubMed

    Liao, Ai-Ho; Liu, Hao-Li; Su, Chia-Hao; Hua, Mu-Yi; Yang, Hung-Wei; Weng, Yu-Ting; Hsu, Po-Hung; Huang, Sheng-Min; Wu, Shih-Yen; Wang, Hsin-Ell; Yen, Tzu-Chen; Li, Pai-Chi

    2012-05-01

    This paper presents new albumin-shelled Gd-DTPA microbubbles (MBs) that can concurrently serve as a dual-modality contrast agent for ultrasound (US) imaging and magnetic resonance (MR) imaging to assist blood-brain barrier (BBB) opening and detect intracerebral hemorrhage (ICH) during focused ultrasound brain drug delivery. Perfluorocarbon-filled albumin-(Gd-DTPA) MBs were prepared with a mean diameter of 2320 nm and concentration of 2.903×10(9) MBs ml(-1) using albumin-(Gd-DTPA) and by sonication with perfluorocarbon (C(3)F(8)) gas. The albumin-(Gd-DTPA) MBs were then centrifuged and the procedure was repeated until the free Gd(3+) ions were eliminated (which were detected by the xylenol orange sodium salt solution). The albumin-(Gd-DTPA) MBs were also characterized and evaluated both in vitro and in vivo by US and MR imaging. Focused US was used with the albumin-(Gd-DTPA) MBs to induce disruption of the BBB in 18 rats. BBB disruption was confirmed with contrast-enhanced T(1)-weighted turbo-spin-echo sequence MR imaging. Heavy T(2)*-weighted 3D fast low-angle shot sequence MR imaging was used to detect ICH. In vitro US imaging experiments showed that albumin-(Gd-DTPA) MBs can significantly enhance the US contrast in T(1)-, T(2)- and T(2)*-weighted MR images. The r(1) and r(2) relaxivities for Gd-DTPA were 7.69 and 21.35 s(-1)mM(-1), respectively, indicating that the MBs represent a positive contrast agent in T(1)-weighted images. In vivo MR imaging experiments on 18 rats showed that focused US combined with albumin-(Gd-DTPA) MBs can be used to both induce disruption of the BBB and detect ICH. To compare the signal intensity change between pure BBB opening and BBB opening accompanying ICH, albumin-(Gd-DTPA) MB imaging can provide a ratio of 5.14 with significant difference (p = 0.026), whereas Gd-DTPA imaging only provides a ratio of 2.13 and without significant difference (p = 0.108). The results indicate that albumin-(Gd-DTPA) MBs have potential as a US/MR dual

  19. Paramagnetic perfluorocarbon-filled albumin-(Gd-DTPA) microbubbles for the induction of focused-ultrasound-induced blood-brain barrier opening and concurrent MR and ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Liao, Ai-Ho; Liu, Hao-Li; Su, Chia-Hao; Hua, Mu-Yi; Yang, Hung-Wei; Weng, Yu-Ting; Hsu, Po-Hung; Huang, Sheng-Min; Wu, Shih-Yen; Wang, Hsin-Ell; Yen, Tzu-Chen; Li, Pai-Chi

    2012-05-01

    This paper presents new albumin-shelled Gd-DTPA microbubbles (MBs) that can concurrently serve as a dual-modality contrast agent for ultrasound (US) imaging and magnetic resonance (MR) imaging to assist blood-brain barrier (BBB) opening and detect intracerebral hemorrhage (ICH) during focused ultrasound brain drug delivery. Perfluorocarbon-filled albumin-(Gd-DTPA) MBs were prepared with a mean diameter of 2320 nm and concentration of 2.903×109 MBs ml-1 using albumin-(Gd-DTPA) and by sonication with perfluorocarbon (C3F8) gas. The albumin-(Gd-DTPA) MBs were then centrifuged and the procedure was repeated until the free Gd3+ ions were eliminated (which were detected by the xylenol orange sodium salt solution). The albumin-(Gd-DTPA) MBs were also characterized and evaluated both in vitro and in vivo by US and MR imaging. Focused US was used with the albumin-(Gd-DTPA) MBs to induce disruption of the BBB in 18 rats. BBB disruption was confirmed with contrast-enhanced T1-weighted turbo-spin-echo sequence MR imaging. Heavy T2*-weighted 3D fast low-angle shot sequence MR imaging was used to detect ICH. In vitro US imaging experiments showed that albumin-(Gd-DTPA) MBs can significantly enhance the US contrast in T1-, T2- and T2*-weighted MR images. The r1 and r2 relaxivities for Gd-DTPA were 7.69 and 21.35 s-1mM-1, respectively, indicating that the MBs represent a positive contrast agent in T1-weighted images. In vivo MR imaging experiments on 18 rats showed that focused US combined with albumin-(Gd-DTPA) MBs can be used to both induce disruption of the BBB and detect ICH. To compare the signal intensity change between pure BBB opening and BBB opening accompanying ICH, albumin-(Gd-DTPA) MB imaging can provide a ratio of 5.14 with significant difference (p = 0.026), whereas Gd-DTPA imaging only provides a ratio of 2.13 and without significant difference (p = 0.108). The results indicate that albumin-(Gd-DTPA) MBs have potential as a US/MR dual-modality contrast agent for

  20. Focused Ultrasound-Induced Blood-Brain Barrier Opening: Association with Mechanical Index and Cavitation Index Analyzed by Dynamic Contrast-Enhanced Magnetic-Resonance Imaging.

    PubMed

    Chu, Po-Chun; Chai, Wen-Yen; Tsai, Chih-Hung; Kang, Shih-Tsung; Yeh, Chih-Kuang; Liu, Hao-Li

    2016-01-01

    Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery. PMID:27630037

  1. Focused Ultrasound-Induced Blood-Brain Barrier Opening: Association with Mechanical Index and Cavitation Index Analyzed by Dynamic Contrast-Enhanced Magnetic-Resonance Imaging

    NASA Astrophysics Data System (ADS)

    Chu, Po-Chun; Chai, Wen-Yen; Tsai, Chih-Hung; Kang, Shih-Tsung; Yeh, Chih-Kuang; Liu, Hao-Li

    2016-09-01

    Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery.

  2. Focused Ultrasound-Induced Blood-Brain Barrier Opening: Association with Mechanical Index and Cavitation Index Analyzed by Dynamic Contrast-Enhanced Magnetic-Resonance Imaging

    PubMed Central

    Chu, Po-Chun; Chai, Wen-Yen; Tsai, Chih-Hung; Kang, Shih-Tsung; Yeh, Chih-Kuang; Liu, Hao-Li

    2016-01-01

    Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery. PMID:27630037

  3. Noninvasive localized delivery of Herceptin to the mouse brain by MRI-guided focused ultrasound-induced blood-brain barrier disruption

    NASA Astrophysics Data System (ADS)

    Kinoshita, Manabu; McDannold, Nathan; Jolesz, Ferenc A.; Hynynen, Kullervo

    2006-08-01

    Antibody-based anticancer agents are promising chemotherapeutic agents. Among these agents, Herceptin (trastuzumab), a humanized anti-human epidermal growth factor receptor 2 (HER2/c-erbB2) monoclonal antibody, has been used successfully in patients with breast cancer. However, in patients with brain metastasis, the blood-brain barrier limits its use, and a different delivery method is needed to treat these patients. Here, we report that Herceptin can be delivered locally and noninvasively into the mouse central nervous system through the blood-brain barrier under image guidance by using an MRI-guided focused ultrasound blood-brain barrier disruption technique. The amount of Herceptin delivered to the target tissue was correlated with the extent of the MRI-monitored barrier opening, making it possible to estimate indirectly the amount of Herceptin delivered. Histological changes attributable to this procedure were minimal. This method may represent a powerful technique for the delivery of macromolecular agents such as antibodies to treat patients with diseases of the central nervous system. brain tumor | microbubble

  4. Gold-nanorod contrast-enhanced photoacoustic micro-imaging of focused-ultrasound induced blood-brain-barrier opening in a rat model

    NASA Astrophysics Data System (ADS)

    Wang, Po-Hsun; Liu, Hao-Li; Hsu, Po-Hung; Lin, Chia-Yu; Chris Wang, Churng-Ren; Chen, Pin-Yuan; Wei, Kuo-Chen; Yen, Tzu-Chen; Li, Meng-Lin

    2012-06-01

    In this study, we develop a novel photoacoustic imaging technique based on gold nanorods (AuNRs) for quantitatively monitoring focused-ultrasound (FUS) induced blood-brain barrier (BBB) opening in a rat model in vivo. This study takes advantage of the strong near-infrared absorption (peak at ~800 nm) of AuNRs and the extravasation tendency from BBB opening foci due to their nano-scale size to passively label the BBB disruption area. Experimental results show that AuNR contrast-enhanced photoacoustic microscopy (PAM) successfully reveals the spatial distribution and temporal response of BBB disruption area in the rat brains. The quantitative measurement of contrast enhancement has potential to estimate the local concentration of AuNRs and even the dosage of therapeutic molecules when AuNRs are further used as nano-carrier for drug delivery or photothermal therapy. The photoacoustic results also provide complementary information to MRI, being helpful to discover more details about FUS induced BBB opening in small animal models.

  5. Magnetic-resonance imaging for kinetic analysis of permeability changes during focused ultrasound-induced blood-brain barrier opening and brain drug delivery.

    PubMed

    Chai, Wen-Yen; Chu, Po-Chun; Tsai, Meng-Yen; Lin, Yu-Chun; Wang, Jiun-Jie; Wei, Kuo-Chen; Wai, Yau-Yau; Liu, Hao-Li

    2014-10-28

    Focused ultrasound (FUS) with the presence of microbubbles has been shown to induce transient and local opening of the blood-brain barrier (BBB) for the delivery of therapeutic molecules which normally cannot penetrate into the brain. The success of FUS brain-drug delivery relies on its integration with in-vivo imaging to monitor kinetic change of therapeutic molecules into the brain. In this study, we developed a dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) technique for kinetic analysis of delivered molecules during FUS-BBB opening. Three kinetic parameters (Ktrans, Ve, Kep) were characterized dynamically to describe BBB-permeability at two FUS exposure conditions (0.4 or 0.8MPa) over 24h. Ktrans, defined as the influx volume transfer constant from plasma to EES, and Ve, the EES volume fraction, were both found to be pressure-dependent. Ktrans and Ve showed a peak increase of 0.0086-0.0131min(-1) (for 0.4-0.8MPa pressure), and 0.0431-0.0692, respectively, immediately after FUS exposure. Both parameters subsequently decreased exponentially as a function of time, with estimated half-lives of decay of 2.89-5.3 and 2.2-4.93h, respectively. The kinetics of Kep, defined as the efflux rate constant from the extracellular extravascular space (EES) to the plasma, were complementary to Ktrans, with an initial decrease from 0.2010 to 0.1901min(-1) followed by a significantly longer recovery time (half-life of 17.39-99.92h). Our observations strongly supported the existence of imbalanced and mismatched kinetics of influx (Ktrans) and efflux (Kep) between the plasma and EES, indicating the existence of directional permeability during FUS-BBB opening. We further showed that kinetic change determined by DCE-MRI correlated well with the concentration of Evans Blue (EB)-albumin (coefficient of 0.74-0.89). These findings suggest that MRI kinetic monitoring may serve as an alternative method for in-vivo monitoring of pharmacokinetics and pharmacodynamics (PK

  6. Improved astigmatic focus error detection method

    NASA Technical Reports Server (NTRS)

    Bernacki, Bruce E.

    1992-01-01

    All easy-to-implement focus- and track-error detection methods presently used in magneto-optical (MO) disk drives using pre-grooved media suffer from a side effect known as feedthrough. Feedthrough is the unwanted focus error signal (FES) produced when the optical head is seeking a new track, and light refracted from the pre-grooved disk produces an erroneous FES. Some focus and track-error detection methods are more resistant to feedthrough, but tend to be complicated and/or difficult to keep in alignment as a result of environmental insults. The astigmatic focus/push-pull tracking method is an elegant, easy-to-align focus- and track-error detection method. Unfortunately, it is also highly susceptible to feedthrough when astigmatism is present, with the worst effects caused by astigmatism oriented such that the tangential and sagittal foci are at 45 deg to the track direction. This disclosure outlines a method to nearly completely eliminate the worst-case form of feedthrough due to astigmatism oriented 45 deg to the track direction. Feedthrough due to other primary aberrations is not improved, but performance is identical to the unimproved astigmatic method.

  7. Magnetoresistive Flux Focusing Eddy Current Flaw Detection

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A. (Inventor); Namkung, Min (Inventor); Simpson, John W. (Inventor)

    2005-01-01

    A giant magnetoresistive flux focusing eddy current device effectively detects deep flaws in thick multilayer conductive materials. The probe uses an excitation coil to induce eddy currents in conducting material perpendicularly oriented to the coil s longitudinal axis. A giant magnetoresistive (GMR) sensor, surrounded by the excitation coil, is used to detect generated fields. Between the excitation coil and GMR sensor is a highly permeable flux focusing lens which magnetically separates the GMR sensor and excitation coil and produces high flux density at the outer edge of the GMR sensor. The use of feedback inside the flux focusing lens enables complete cancellation of the leakage fields at the GMR sensor location and biasing of the GMR sensor to a location of high magnetic field sensitivity. In an alternate embodiment, a permanent magnet is positioned adjacent to the GMR sensor to accomplish the biasing. Experimental results have demonstrated identification of flaws up to 1 cm deep in aluminum alloy structures. To detect deep flaws about circular fasteners or inhomogeneities in thick multi-layer conductive materials, the device is mounted in a hand-held rotating probe assembly that is connected to a computer for system control, data acquisition, processing and storage.

  8. Magnetoresistive flux focusing eddy current flaw detection

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A. (Inventor); Namkung, Min (Inventor); Simpson, John W. (Inventor)

    2005-01-01

    A giant magnetoresistive flux focusing eddy current device effectively detects deep flaws in thick multilayer conductive materials. The probe uses an excitation coil to induce eddy currents in conducting material perpendicularly oriented to the coil's longitudinal axis. A giant magnetoresistive (GMR) sensor, surrounded by the excitation coil, is used to detect generated fields. Between the excitation coil and GMR sensor is a highly permeable flux focusing lens which magnetically separates the GMR sensor and excitation coil and produces high flux density at the outer edge of the GMR sensor. The use of feedback inside the flux focusing lens enables complete cancellation of the leakage fields at the GMR sensor location and biasing of the GMR sensor to a location of high magnetic field sensitivity. In an alternate embodiment, a permanent magnet is positioned adjacent to the GMR sensor to accomplish the biasing. Experimental results have demonstrated identification of flaws up to 1 cm deep in aluminum alloy structures. To detect deep flaws about circular fasteners or inhomogeneities in thick multilayer conductive materials, the device is mounted in a hand-held rotating probe assembly that is connected to a computer for system control, data acquisition, processing and storage.

  9. Controlled Ultrasound-Induced Blood-Brain Barrier Disruption Using Passive Acoustic Emissions Monitoring

    PubMed Central

    Arvanitis, Costas D.; Livingstone, Margaret S.; Vykhodtseva, Natalia; McDannold, Nathan

    2012-01-01

    The ability of ultrasonically-induced oscillations of circulating microbubbles to permeabilize vascular barriers such as the blood-brain barrier (BBB) holds great promise for noninvasive targeted drug delivery. A major issue has been a lack of control over the procedure to ensure both safe and effective treatment. Here, we evaluated the use of passively-recorded acoustic emissions as a means to achieve this control. An acoustic emissions monitoring system was constructed and integrated into a clinical transcranial MRI-guided focused ultrasound system. Recordings were analyzed using a spectroscopic method that isolates the acoustic emissions caused by the microbubbles during sonication. This analysis characterized and quantified harmonic oscillations that occur when the BBB is disrupted, and broadband emissions that occur when tissue damage occurs. After validating the system's performance in pilot studies that explored a wide range of exposure levels, the measurements were used to control the ultrasound exposure level during transcranial sonications at 104 volumes over 22 weekly sessions in four macaques. We found that increasing the exposure level until a large harmonic emissions signal was observed was an effective means to ensure BBB disruption without broadband emissions. We had a success rate of 96% in inducing BBB disruption as measured by in contrast-enhanced MRI, and we detected broadband emissions in less than 0.2% of the applied bursts. The magnitude of the harmonic emissions signals was significantly (P<0.001) larger for sonications where BBB disruption was detected, and it correlated with BBB permeabilization as indicated by the magnitude of the MRI signal enhancement after MRI contrast administration (R2 = 0.78). Overall, the results indicate that harmonic emissions can be a used to control focused ultrasound-induced BBB disruption. These results are promising for clinical translation of this technology. PMID:23029240

  10. Preface to the Focus Issue: Chaos Detection Methods and Predictability

    SciTech Connect

    Gottwald, Georg A.; Skokos, Charalampos

    2014-06-01

    This Focus Issue presents a collection of papers originating from the workshop Methods of Chaos Detection and Predictability: Theory and Applications held at the Max Planck Institute for the Physics of Complex Systems in Dresden, June 17–21, 2013. The main aim of this interdisciplinary workshop was to review comprehensively the theory and numerical implementation of the existing methods of chaos detection and predictability, as well as to report recent applications of these techniques to different scientific fields. The collection of twelve papers in this Focus Issue represents the wide range of applications, spanning mathematics, physics, astronomy, particle accelerator physics, meteorology and medical research. This Preface surveys the papers of this Issue.

  11. Attention focusing and anomaly detection in systems monitoring

    NASA Technical Reports Server (NTRS)

    Doyle, Richard J.

    1994-01-01

    Any attempt to introduce automation into the monitoring of complex physical systems must start from a robust anomaly detection capability. This task is far from straightforward, for a single definition of what constitutes an anomaly is difficult to come by. In addition, to make the monitoring process efficient, and to avoid the potential for information overload on human operators, attention focusing must also be addressed. When an anomaly occurs, more often than not several sensors are affected, and the partially redundant information they provide can be confusing, particularly in a crisis situation where a response is needed quickly. The focus of this paper is a new technique for attention focusing. The technique involves reasoning about the distance between two frequency distributions, and is used to detect both anomalous system parameters and 'broken' causal dependencies. These two forms of information together isolate the locus of anomalous behavior in the system being monitored.

  12. Automated focusing in bright-field microscopy for tuberculosis detection

    PubMed Central

    OSIBOTE, O.A.; DENDERE, R.; KRISHNAN, S.; DOUGLAS, T.S.

    2010-01-01

    Summary Automated microscopy to detect Mycobacterium tuberculosis in sputum smear slides would enable laboratories in countries with a high tuberculosis burden to cope efficiently with large numbers of smears. Focusing is a core component of automated microscopy, and successful autofocusing depends on selection of an appropriate focus algorithm for a specific task. We examined autofocusing algorithms for bright-field microscopy of Ziehl–Neelsen stained sputum smears. Six focus measures, defined in the spatial domain, were examined with respect to accuracy, execution time, range, full width at half maximum of the peak and the presence of local maxima. Curve fitting around an estimate of the focal plane was found to produce good results and is therefore an acceptable strategy to reduce the number of images captured for focusing and the processing time. Vollath's F4 measure performed best for full z-stacks, with a mean difference of 0.27 μm between manually and automatically determined focal positions, whereas it is jointly ranked best with the Brenner gradient for curve fitting. PMID:20946382

  13. Complete Inhibition Of Ultrasound Induced Cytolysis In The Presence Of Inertial Cavitation

    NASA Astrophysics Data System (ADS)

    Sostaric, Joe Z.; Miyoshi, Norio; Riesz, Peter; De Graff, William G.; Mitchell, James B.

    2006-05-01

    The investigation of ultrasound for biotechnological applications including non-invasive surgery (HIFU), drug/gene delivery to cells (sonoporation) or through the skin (sonophoresis) and ultrasound assisted bioreactors has focused mainly on the physical effects of ultrasound. The beneficial effects of ultrasound rely on a number of application-dependent mechanisms, and may include tissue heating, acoustic streaming or cavitation. Although acoustic cavitation is necessary in some systems, cavitation bubbles simultaneously result in uncontrollable cell damage and cytolysis. Thus, the development of a number of biotechnological uses of ultrasound has been hampered by the necessity to constrain exposure parameters in order to prevent the occurrence of acoustic cavitation or to at least limit the detrimental effects of cavitation. The current study shows that non-toxic concentrations of specific n-alkyl solutes completely inhibit ultrasound induced cytolysis of in vitro suspensions of human leukemia cells (HL-60). Protection of the whole cell population from cytolysis is achieved even under extreme ultrasound exposure conditions that result in cytolysis of 100 % of the cell population in the absence of the n-alkyl solutes. Furthermore, the n-alkyl solutes did not hinder the process of inertial cavitation. This method may allow utilization of beneficial effects of ultrasound and cavitation while protecting cells from cavitation induced cytolysis and thereby presents new possibilities for ultrasound in medicine and biology.

  14. Rotating flux-focusing eddy current probe for flaw detection

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A. (Inventor); Fulton, James P. (Inventor); Nath, Shridhar C. (Inventor); Simpson, John W. (Inventor); Namkung, Min (Inventor)

    1997-01-01

    A flux-focusing electromagnetic sensor which uses a ferromagnetic flux-focusing lens simplifies inspections and increases detectability of fatigue cracks about circular fasteners and other circular inhomogeneities in high conductivity material. The unique feature of the device is the ferrous shield isolating a high-turn pick-up coil from an excitation coil, The use of the magnetic shield is shown to produce a null voltage output across the receiving coil in the presence of an unflawed sample. A redistribution of the current flow in the sample caused by the presence of flaws, however, eliminates the shielding condition and a large output voltage is produced, yielding a clear unambiguous flaw signal. By rotating the probe in a path around a circular fastener such as a rivet while maintaining a constant distance between the probe and the center of a rivet, the signal due to current flow about the rivet can be held constant. Any further changes in the current distribution, such as due to a fatigue crack at the rivet joint, can be detected as an increase in the output voltage above that due to the flow about the rivet head.

  15. The origin of ultrasound-induced friction reduction in microscopic mechanical contacts.

    PubMed

    Hesjedal, Thorsten; Behme, Gerd

    2002-03-01

    We present a study of the origin of ultrasound-induced friction reduction in microscopic mechanical contacts. The effect of friction reduction caused by Rayleigh-type surface acoustic waves (SAWs) is demonstrated for propagating and two-dimensional, standing wave fields using lateral force microscopy (LFM). It is shown that with increasing wave amplitude, friction is completely suppressed. To detect and distinguish between the effect of lateral and vertical surface oscillation components on the cantilever movement, we employed multimode scanning acoustic force microscopy (SAFM). We found that the friction reduction effect is only due to the vertical oscillation component. Because this effect does not appear for purely in-plane polarized Love waves, we concluded that the mechanical diode effect is most probably responsible for the SAW-induced lubrication. This explanation is also supported by vertical and longitudinal SAFM measurements, which show that, in areas where friction is completely suppressed, low frequency vertical cantilever oscillations can still be observed, whereas lateral or torsional oscillations are no longer excited.

  16. Realigning the Focus of Plagiarism Detection Using "Plagiarismdetect.com"

    ERIC Educational Resources Information Center

    Sabapathy, Elangkeeran A/L; Rahim, Rozlan Abd; Jusoff, Kamaruzaman

    2009-01-01

    The purpose of this article is to examine the extent to which "plagiarismdetect.com," an internet help/tool to detect plagiarism helps academicians tackle the ever-growing problem of plagiarism. Concerned with term papers, essays and most of the time with full-blown research reports, a tool like "plagiarismdetect.com" may…

  17. Ultrasonic Sensitivity of Strain-Insensitive Fiber Bragg Grating Sensors and Evaluation of Ultrasound-Induced Strain

    PubMed Central

    Tsuda, Hiroshi; Kumakura, Kenji; Ogihara, Shinji

    2010-01-01

    In conventional ultrasound detection in structures, a fiber Bragg grating (FBG) is glued on or embedded in the structure. However, application of strain to the structure can influence the sensitivity of the FBG toward ultrasound and can prevent its effective detection. An FBG can work as a strain-insensitive ultrasound sensor when it is not directly glued to the monitored structure, but is instead applied to a small thin plate to form a mobile sensor. Another possible configuration is to affix an FBG-inscribed optical fiber without the grating section attached to the monitored structure. In the present study, sensitivity to ultrasound propagated through an aluminum plate was compared for a strain-insensitive FBG sensor and an FBG sensor installed in a conventional manner. Strains induced by ultrasound from a piezoelectric transducer and by quasi-acoustic emission of a pencil lead break were also quantitatively evaluated from the response amplitude of the FBG sensor. Experimental results showed that the reduction in the signal-to-noise ratio for ultrasound detection with strain-insensitive FBG sensors, relative to traditionally-installed FBG sensors, was only 6 dB, and the ultrasound-induced strain varied within a range of sub-micron strains. PMID:22163523

  18. Detection of liquid hazardous molecules using linearly focused Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Cho, Soo Gyeong; Chung, Jin Hyuk

    2013-05-01

    In security, it is an important issue to analyze hazardous materials in sealed bottles. Particularly, prompt nondestructive checking of sealed liquid bottles in a very short time at the checkpoints of crowded malls, stadiums, or airports is of particular importance to prevent probable terrorist attack using liquid explosives. Aiming to design and fabricate a detector for liquid explosives, we have used linearly focused Raman spectroscopy to analyze liquid materials in transparent or semi-transparent bottles without opening their caps. Continuous lasers with 532 nm wavelength and 58 mW/130 mW beam energy have been used for the Raman spectroscopy. Various hazardous materials including flammable liquids and explosive materials have successfully been distinguished and identified within a couple of seconds. We believe that our technique will be one of suitable methods for fast screening of liquid materials in sealed bottles.

  19. Ultrasound Induced Fluorescence of Nanoscale Liposome Contrast Agents

    PubMed Central

    Zhang, Qimei; Morgan, Stephen P.; O’Shea, Paul; Mather, Melissa L.

    2016-01-01

    A new imaging contrast agent is reported that provides an increased fluorescent signal upon application of ultrasound (US). Liposomes containing lipids labelled with pyrene were optically excited and the excimer fluorescence emission intensity was detected in the absence and presence of an ultrasound field using an acousto-fluorescence setup. The acousto-fluorescence dynamics of liposomes containing lipids with pyrene labelled on the fatty acid tail group (PyPC) and the head group (PyPE) were compared. An increase in excimer emission intensity following exposure to US was observed for both cases studied. The increased intensity and time constants were found to be different for the PyPC and PyPE systems, and dependent on the applied US pressure and exposure time. The greatest change in fluorescence intensity (130%) and smallest rise time constant (0.33 s) are achieved through the use of PyPC labelled liposomes. The mechanism underlying the observed increase of the excimer emission intensity in PyPC labelled liposomes is proposed to arise from the “wagging” of acyl chains which involves fast response and requires lower US pressure. This is accompanied by increased lipid lateral diffusivity at higher ultrasound pressures, a mechanism that is also active in the PyPE labelled liposomes. PMID:27467748

  20. Focus detection from digital in-line holograms based on spectral l1 norms.

    PubMed

    Li, Weichang; Loomis, Nick C; Hu, Qiao; Davis, Cabell S

    2007-10-01

    A rapid focus-detection technique based directly on the spectral content of digital holograms is developed. It differs from previous approaches in that it does not need a full reconstruction of the image. The technique uses l(1) norms of object spectral components associated with the real and imaginary parts of the reconstruction kernel. Further, the l(1) norms can be computed efficiently in the spatial frequency domain using a polar coordinate system, yielding a drastic speedup of approximately 2 orders of magnitude compared with image-based focus detection. Significant computational savings are achieved when subsequent image reconstructions are done selectively over the detected focus distances. Focus-detection results from holograms of plankton are demonstrated that show the technique is both accurate and robust. PMID:17912295

  1. Ultrasensitive detection of microbial cells using magnetic focus enhanced lateral flow sensors.

    PubMed

    Ren, Wen; Cho, Il-Hoon; Zhou, Zhongwu; Irudayaraj, Joseph

    2016-04-01

    We report on an improved lateral flow immunoassay (LFIA) sensor with a magnetic focus for ultrasensitive naked-eye detection of pathogenic microorganisms at a near single cell limit without any pre-enrichment steps, by allowing the magnetic probes to focus the labelled pathogens to the target zone of the LF strip.

  2. A phantom for visualization of three-dimensional drug release by ultrasound-induced mild hyperthermia

    PubMed Central

    Lai, Chun-Yen; Kruse, Dustin; Seo, Jai Woong; Kheirolomoom, Azadeh; Ferrara, Katherine W.

    2013-01-01

    Purpose: Ultrasound-induced mild hyperthermia has advantages for noninvasive, localized and controlled drug delivery. In this study, a tissue-mimicking agarose-based phantom with a thermally sensitive indicator was developed for studying the spatial drug delivery profile using ultrasound-induced mild hyperthermia. Methods: Agarose powder, regular evaporated milk, Dulbecco's phosphate-buffered saline (DPBS), n-propanol, and silicon carbide powder were homogeneously mixed with low temperature sensitive liposomes (LTSLs) loaded with a self-quenched near-infrared (NIR) fluorescent dye. A dual-mode linear array ultrasound transducer was used for insonation at 1.54 MHz with a total acoustic power and acoustic pressure of 2.0 W and 1.5 MPa, respectively. After insonation, the dye release pattern in the phantom was quantified based on optical images, and the three-dimensional release profile was reconstructed and analyzed. A finite-difference time-domain-based algorithm was developed to simulate both the temperature distribution and spatial dye diffusion as a function of time. Finally, the simulated dye diffusion patterns were compared to experimental measurements. Results: Self-quenching of the fluorescent dye in DPBS was substantial at a concentration of 6.25 × 10−2 mM or greater. The transition temperature of LTSLs in the phantom was 35 °C, and the release reached 90% at 37 °C. The simulated temperature for hyperthermia correlated with the thermocouple measurements with a mean error between 0.03 ± 0.01 and 0.06 ± 0.02 °C. The R2 value between the experimental and simulated spatial extent of the dye diffusion, defined by the half-peak level in the elevation, lateral and depth directions, was 0.99 (slope = 1.08), 0.95 (slope = 0.99), and 0.80 (slope = 1.04), respectively, indicating the experimental and simulated dye release profiles were similar. Conclusions: The combination of LTSLs encapsulating a fluorescent dye and an optically transparent phantom is

  3. Macromolecular crowding conditions enhance glycation and oxidation of whey proteins in ultrasound-induced Maillard reaction.

    PubMed

    Perusko, Marija; Al-Hanish, Ayah; Cirkovic Velickovic, Tanja; Stanic-Vucinic, Dragana

    2015-06-15

    High intensity ultrasound (HIUS) can promote Maillard reaction (MR). Macromolecular crowding conditions accelerate reactions and stabilise protein structure. The aim of this study was to investigate if combined application of ultrasound and macromolecular crowding can improve efficiency of MR. The presence of crowding agent (polyethylene glycol) significantly increased ultrasound-induced whey protein (WP) glycation by arabinose. An increase in glycation efficiency results only in slight change of WP structure. Macromolecular crowding intensifies oxidative modifications of WP, as well as formation of amyloid-like structures by enhancement of MR. Solubility at different pH, thermal stability and antioxidative capacity of glycated WP were increased, especially in the presence of crowding agent, compared to sonicated nonglycated proteins. The application of HIUS under crowding conditions can be a new approach for enhancement of reactions in general, enabling short processing time and mild conditions, while preserving protein structure and minimising protein aggregation.

  4. Three-Dimensional Simulation of Ultrasound-Induced Microalgal Cell Disruption.

    PubMed

    Wang, M; Yuan, W; Hale, Andy

    2016-03-01

    The three-dimensional distribution (x, y, and z) of ultrasound-induced microalgal cell disruption in a sonochemical reactor was predicted by solving the Helmholtz equation using a three-dimensional acoustic module in the COMSOL Multiphysics software. The simulated local ultrasound pressure at any given location (x, y, and z) was found to correlate with cell disruption of a freshwater alga, Scenedesmus dimorphus, represented by the change of algal cell particle/debris concentration, chlorophyll-a fluorescence density (CAFD), and Nile red stained lipid fluorescence density (LFD), which was also validated by the model reaction of potassium iodide oxidation (the Weissler reaction). Furthermore, the effect of ultrasound power intensity and processing duration on algal cell disruption was examined to address the limitation of the model. PMID:26660670

  5. Macromolecular crowding conditions enhance glycation and oxidation of whey proteins in ultrasound-induced Maillard reaction.

    PubMed

    Perusko, Marija; Al-Hanish, Ayah; Cirkovic Velickovic, Tanja; Stanic-Vucinic, Dragana

    2015-06-15

    High intensity ultrasound (HIUS) can promote Maillard reaction (MR). Macromolecular crowding conditions accelerate reactions and stabilise protein structure. The aim of this study was to investigate if combined application of ultrasound and macromolecular crowding can improve efficiency of MR. The presence of crowding agent (polyethylene glycol) significantly increased ultrasound-induced whey protein (WP) glycation by arabinose. An increase in glycation efficiency results only in slight change of WP structure. Macromolecular crowding intensifies oxidative modifications of WP, as well as formation of amyloid-like structures by enhancement of MR. Solubility at different pH, thermal stability and antioxidative capacity of glycated WP were increased, especially in the presence of crowding agent, compared to sonicated nonglycated proteins. The application of HIUS under crowding conditions can be a new approach for enhancement of reactions in general, enabling short processing time and mild conditions, while preserving protein structure and minimising protein aggregation. PMID:25660883

  6. Focusing Error Detection Method in Microholographic Data Storage System Using Polarization Characteristics

    NASA Astrophysics Data System (ADS)

    Kim, Taeseob; Im, Chang-Hyuk; Lee, Sang-Hyuck; Kim, Nakyeong; Park, No-Cheol; Yang, Hyunseok; Park, Young-Pil; Park, Kyoung-Su

    2011-09-01

    We present a disk-focusing error detection method for microholographic data storage systems using polarization characteristics. In high-speed optical storage systems, disturbances exist along the vertical direction of a disk. The diffraction efficiency of a readout signal depends on the distance between the focusing point of the reference beam and the vertical center of the microholographic grating. The proposed disk focusing error detection method uses only one laser source, unlike most existing systems, which use two laser sources. By using polarization characteristics, disk-focusing and reading beams are inserted in the media without interference, and the proposed system achieves the simultaneous reading of microholograms and disk-focusing control. By evaluating the focus error signal, we verified the reliability of the optical path and tolerable S-curve (FES) balance (1.8%) for the proposed system. It is possible to achieve a diffraction efficiency of over 90% at the best focus position using the proposed disk-focusing method.

  7. Measurement of focused ultrasonic fields based on colour edge detection and curve fitting

    NASA Astrophysics Data System (ADS)

    Zhu, H.; Chang, S.; Yang, P.; He, L.

    2016-03-01

    This paper utilizes firstly both a scanning device and an optic fiber hydrophone to establish a measurement system, and then proposes the parameter measurement of the focused transducer based on edge detection of the visualized acoustic data and curve fitting. The measurement system consists of a water tank with wedge absorber, stepper motors driver, system controller, a focused transducer, an optic fiber hydrophone and data processing software. On the basis of the visualized processing for the original scanned data, the -3 dB beam width of the focused transducer is calculated using the edge detection of the acoustic visualized image and circle fitting method by minimizing algebraic distance. Experiments on the visualized ultrasound data are implemented to verify the feasibility of the proposed method. The data obtained from the scanning device are utilized to reconstruct acoustic fields, and it is found that the -3 dB beam width of the focused transducer can be predicted accurately.

  8. Stand-off explosive detection utilizing low power stimulated emission nuclear quadrupole resonance detection and subwavelength focusing wideband super lens

    NASA Astrophysics Data System (ADS)

    Apostolos, John; Mouyos, William; Feng, Judy; Chase, Walter

    2015-05-01

    The need for advanced techniques to detect improvised explosive devices (IED) at stand-off distances greater than ten (10) meters has driven AMI Research and Development (AMI) to develop a solution to detect and identify the threat utilizing a forward looking Synthetic Aperture Radar (SAR) combined with our CW radar technology Nuclear Quadrupole Resonance (NQR) detection system. The novel features include a near-field sub-wavelength focusing antenna, a wide band 300 KHz to 300 MHz rapidly scanning CW radar facilitated by a high Q antenna/tuner, and an advanced processor utilizing Rabi transitions where the nucleus oscillates between states under the time dependent incident electromagnetic field and alternately absorbs energy from the incident field while emitting coherent energy via stimulated emission. AMI's Sub-wavelength Focusing Wide Band Super Lens uses a Near-Field SAR, making detection possible at distances greater than ten (10) meters. This super lens is capable of operating on the near-field and focusing electromagnetic waves to resolutions beyond the diffraction limit. When applied to the case of a vehicle approaching an explosive hazard the methodologies of synthetic aperture radar is fused with the array based super resolution and the NQR data processing detecting the explosive hazard.

  9. Usefulness of MEG magnetometer for spike detection in patients with mesial temporal epileptic focus.

    PubMed

    Enatsu, R; Mikuni, N; Usui, K; Matsubayashi, J; Taki, J; Begum, T; Matsumoto, R; Ikeda, A; Nagamine, T; Fukuyama, H; Hashimoto, N

    2008-07-15

    The present study investigated the sensitivity of magnetoencephalography (MEG) for spikes depending on sensor type in patients with mesial temporal epileptic focus. We recorded MEG in 6 patients with mesial temporal epileptic focus using two sensor types (magnetometer and gradiometer) simultaneously. The number of spikes detected and the corresponding equivalent current dipole (ECD) parameters (distance from the coordinated head center (radius), and dipole moment) were evaluated with respect to sensor type. Among 426 MEG 'consensus spikes' determined by 3 reviewers, 378 spikes satisfied the predetermined criteria for source localization. Comparing ECD parameters, spikes detected by magnetometer alone displayed a smaller radius and larger dipole moment than those detected by gradiometer alone. Spikes estimated in the mesial temporal area were more frequently detected by magnetometer alone (38.5%) than by gradiometer alone (11.5%), whereas spikes in the lateral temporal area were detected less by magnetometer alone (3.7%) than by gradiometer alone (53.9%). The present results suggest that a magnetometer is advantageous for spike detection in patients with mesial temporal epileptic focus. This also implies the higher sensitivity of magnetometer for deep sources.

  10. Animal board invited review: precision livestock farming for dairy cows with a focus on oestrus detection.

    PubMed

    Mottram, T

    2016-10-01

    Dairy cows are high value farm animals requiring careful management to achieve the best results. Since the advent of robotic and high throughput milking, the traditional few minutes available for individual human attention daily has disappeared and new automated technologies have been applied to improve monitoring of dairy cow production, nutrition, fertility, health and welfare. Cows milked by robots must meet legal requirements to detect healthy milk. This review focuses on emerging technical approaches in those areas of high cost to the farmer (fertility, metabolic disorders, mastitis, lameness and calving). The availability of low cost tri-axial accelerometers and wireless telemetry has allowed accurate models of behaviour to be developed and sometimes combined with rumination activity detected by acoustic sensors to detect oestrus; other measures (milk and skin temperature, electronic noses, milk yield) have been abandoned. In-line biosensors have been developed to detect markers for ovulation, pregnancy, lactose, mastitis and metabolic changes. Wireless telemetry has been applied to develop boluses for monitoring the rumen pH and temperature to detect metabolic disorders. Udder health requires a multisensing approach due to the varying inflammatory responses collectively described as mastitis. Lameness can be detected by walk over weigh cells, but also by various types of video image analysis and speed measurement. Prediction and detection of calving time is an area of active research mostly focused on behavioural change.

  11. A Distance Measure for Attention Focusing and Anomaly Detection in Systems Monitoring

    NASA Technical Reports Server (NTRS)

    Doyle, R.

    1994-01-01

    Any attempt to introduce automation into the monitoring of complex physical systems must start from a robust anomaly detection capability. This task is far from straightforward, for a single definition of what constitutes an anomaly is difficult to come by. In addition, to make the monitoring process efficient, and to avoid the potential for information overload on human operators, attention focusing must also be addressed. When an anomaly occurs, more often than not several sensors are affected, and the partially redundant information they provide can be confusing, particularly in a crisis situation where a response is needed quickly. Previous results on extending traditional anomaly detection techniques are summarized. The focus of this paper is a new technique for attention focusing.

  12. Application of a focus formation assay for detection and titration of porcine epidemic diarrhea virus.

    PubMed

    Cruz, Deu John M; Shin, Hyun-Jin

    2007-10-01

    A focus formation assay (FFA) for detection and titration of porcine epidemic diarrhea virus (PEDV) in a micro-culture system using Vero cells and PAP staining technique was evaluated. A linear correlation between the virus dilution and virus titer determined by FFA was observed between the range of 10 and 30 foci per well. Comparative analysis between FFA and plaque assay showed no significant difference in estimating the titer of cell adapted PEDV. However, the culture time required for detecting the virus was considerably shorter for FFA. In addition, FFA had higher sensitivity for detecting field isolates of PEDV as well as positive identification of the virus with the antibody specific reaction. A broader range of dilutions and number of replicates may be used for titration. A FFA may be applied as an alternative method for detection and titration of PEDV.

  13. Multi-focus parallel detection of fluorescent molecules at picomolar concentration with photonic nanojets arrays

    SciTech Connect

    Ghenuche, Petru; Torres, Juan de; Ferrand, Patrick; Wenger, Jérôme

    2014-09-29

    Fluorescence sensing and fluorescence correlation spectroscopy (FCS) are powerful methods to detect and characterize single molecules; yet, their use has been restricted by expensive and complex optical apparatus. Here, we present a simple integrated design using a self-assembled bi-dimensional array of microspheres to realize multi-focus parallel detection scheme for FCS. We simultaneously illuminate and collect the fluorescence from several tens of microspheres, which all generate their own photonic nanojet to efficiently excite the molecules and collect the fluorescence emission. Each photonic nanojet contributes to the global detection volume, reaching FCS detection volumes of several tens of femtoliters while preserving the fluorescence excitation and collection efficiencies. The microspheres photonic nanojets array enables FCS experiments at low picomolar concentrations with a drastic reduction in apparatus cost and alignment constraints, ideal for microfluidic chip integration.

  14. Low intensity-pulsed ultrasound induced apoptosis of human hepatocellular carcinoma cells in vitro.

    PubMed

    Shi, Mingfang; Liu, Bangzhong; Liu, Guanghua; Wang, Ping; Yang, Mingzhen; Li, Yun; Zhou, Jian

    2016-01-01

    The present study was conducted to determine whether low intensity-pulsed ultrasound (LIPUS) could induce apoptosis of human hepatocellular carcinoma cells, SMMC-7721, and to define the mechanism of ultrasound-induced apoptosis, in vitro. MTT assay was used to measure cell proliferation. Apoptosis was investigated by multiple methods such as flow cytometry, DNA fragmentation, Ca(2+) mobilizations, pro- and anti-apoptotic protein expression, and light as well as ultramicroscopic morphology. The results provide evidence that LIPUS induced a dose-dependent effect on cell viability and apoptosis of SMMC-7721 cells. Specifically, exposure of cells to >0.5 W/cm(2) intensity significantly increased cell apoptosis, caused shifts in cell cycle phase, and induced structural changes. Ultrasound significantly increased intracellular Ca(2+) concentrations and modulated expression of caspase-3, Bcl-2 and Bax. The findings suggest that this novel technology can be used to induce SMMC-7721 apoptosis via the Ca(2+)/mitochondrial pathway and could potentially be of clinical use for the treatment of hepatocellular carcinoma (SMMC-7721 cell line) and other cancers.

  15. Histological and Ultrastructural Effects of Ultrasound-induced Cavitation on Human Skin Adipose Tissue

    PubMed Central

    Li, Alessandro Quattrini; Freschi, Giancarlo; Russo, Giulia Lo

    2013-01-01

    Background: In aesthetic medicine, the most promising techniques for noninvasive body sculpturing purposes are based on ultrasound-induced fat cavitation. Liporeductive ultrasound devices afford clinically relevant subcutaneous fat pad reduction without significant adverse reactions. This study aims at evaluating the histological and ultrastructural changes induced by ultrasound cavitation on the different cell components of human skin. Methods: Control and ultrasound-treated ex vivo abdominal full-thickness skin samples and skin biopsies from patients pretreated with or without ultrasound cavitation were studied histologically, morphometrically, and ultrastructurally to evaluate possible changes in adipocyte size and morphology. Adipocyte apoptosis and triglyceride release were also assayed. Clinical evaluation of the effects of 4 weekly ultrasound vs sham treatments was performed by plicometry. Results: Compared with the sham-treated control samples, ultrasound cavitation induced a statistically significant reduction in the size of the adipocytes (P < 0.001), the appearance of micropores and triglyceride leakage and release in the conditioned medium (P < 0.05 at 15 min), or adipose tissue interstitium, without appreciable changes in microvascular, stromal, and epidermal components and in the number of apoptotic adipocytes. Clinically, the ultrasound treatment caused a significant reduction of abdominal fat. Conclusions: This study further strengthens the current notion that noninvasive transcutaneous ultrasound cavitation is a promising and safe technology for localized reduction of fat and provides experimental evidence for its specific mechanism of action on the adipocytes. PMID:25289235

  16. Overcoming MDR by ultrasound-induced hyperthermia and P-glycoprotein modulation.

    PubMed

    Liu, Y; Lillehei, K; Cobb, W N; Christians, U; Ng, K Y

    2001-11-23

    We assessed the effects of combining ultrasound-induced hyperthermia (USHT) with the P-glycoprotein modulator PSC 833 on cellular retention and cytotoxicity of rhodamine 123 (R123) and doxorubicin in the parent and multidrug resistance (MDR) variants of two human cancer lines. USHT significantly increased cellular uptake of R123 and doxorubicin. Without PSC 833, release of R123 and doxorubicin from both USHT-treated and untreated cells was rapid. As expected, PSC 833 (0.5 microM) only slowed their release into the MDR lines. Interestingly, despite the differences in their starting amounts, PSC 833 was effective in prolonging R123 and doxorubicin release from both USHT-treated and untreated MDR cells. PSC 833 did not augment the cytotoxicity of doxorubicin in parent lines but did cause a significant increase in cytotoxicity of doxorubicin in the MDR lines. However, the combined effect of USHT and PSC 833 on cytotoxicity of doxorubicin far exceeded that produced by USHT or PSC 833 alone.

  17. Focusing surface plasmon polaritons and detecting Stokes parameters utilizing nanoslits distributed plasmonic lenses.

    PubMed

    Huang, Feng; Jiang, Xiangqian; Yuan, Haiming; Yang, Hanning; Li, Siren; Sun, Xiudong

    2016-04-01

    A method to detect the full Stokes parameters utilizing a double-ring and Archimedes-curves distributed nanoslits plasmonic lenses is proposed. We demonstrate theoretically and numerically that both of these two plasmonic lenses can focus surface plasmon polaritons to centrally symmetric fields with subwavelength-sized focal spots under linear, elliptical, and circular polarization incidence. The intensity at the focal spots is modulated by the polarization state of incident light. Utilizing this intensity polarization sensitivity, the full Stokes parameters of incident light are detected by recoding only four intensities at the focal spots of these two plasmonic lenses. PMID:27192318

  18. Note: Focus error detection device for thermal expansion-recovery microscopy (ThERM).

    PubMed

    Domené, E A; Martínez, O E

    2013-01-01

    An innovative focus error detection method is presented that is only sensitive to surface curvature variations, canceling both thermoreflectance and photodefelection effects. The detection scheme consists of an astigmatic probe laser and a four-quadrant detector. Nonlinear curve fitting of the defocusing signal allows the retrieval of a cutoff frequency, which only depends on the thermal diffusivity of the sample and the pump beam size. Therefore, a straightforward retrieval of the thermal diffusivity of the sample is possible with microscopic lateral resolution and high axial resolution (~100 pm). PMID:23387710

  19. Note: Focus error detection device for thermal expansion-recovery microscopy (ThERM).

    PubMed

    Domené, E A; Martínez, O E

    2013-01-01

    An innovative focus error detection method is presented that is only sensitive to surface curvature variations, canceling both thermoreflectance and photodefelection effects. The detection scheme consists of an astigmatic probe laser and a four-quadrant detector. Nonlinear curve fitting of the defocusing signal allows the retrieval of a cutoff frequency, which only depends on the thermal diffusivity of the sample and the pump beam size. Therefore, a straightforward retrieval of the thermal diffusivity of the sample is possible with microscopic lateral resolution and high axial resolution (~100 pm).

  20. Focusing surface plasmon polaritons and detecting Stokes parameters utilizing nanoslits distributed plasmonic lenses.

    PubMed

    Huang, Feng; Jiang, Xiangqian; Yuan, Haiming; Yang, Hanning; Li, Siren; Sun, Xiudong

    2016-04-01

    A method to detect the full Stokes parameters utilizing a double-ring and Archimedes-curves distributed nanoslits plasmonic lenses is proposed. We demonstrate theoretically and numerically that both of these two plasmonic lenses can focus surface plasmon polaritons to centrally symmetric fields with subwavelength-sized focal spots under linear, elliptical, and circular polarization incidence. The intensity at the focal spots is modulated by the polarization state of incident light. Utilizing this intensity polarization sensitivity, the full Stokes parameters of incident light are detected by recoding only four intensities at the focal spots of these two plasmonic lenses.

  1. Effect of gravitational focusing on annual modulation in dark-matter direct-detection experiments.

    PubMed

    Lee, Samuel K; Lisanti, Mariangela; Peter, Annika H G; Safdi, Benjamin R

    2014-01-10

    The scattering rate in dark-matter direct-detection experiments should modulate annually due to Earth's orbit around the Sun. The rate is typically thought to be extremized around June 1, when the relative velocity of Earth with respect to the dark-matter wind is maximal. We point out that gravitational focusing can alter this modulation phase. Unbound dark-matter particles are focused by the Sun's gravitational potential, affecting their phase-space density in the lab frame. Gravitational focusing can result in a significant overall shift in the annual-modulation phase, which is most relevant for dark matter with low scattering speeds. The induced phase shift for light O(10)  GeV dark matter may also be significant, depending on the threshold energy of the experiment.

  2. Defect detection around rebars in concrete using focused ultrasound and reverse time migration.

    PubMed

    Beniwal, Surendra; Ganguli, Abhijit

    2015-09-01

    Experimental and numerical investigations have been performed to assess the feasibility of damage detection around rebars in concrete using focused ultrasound and a Reverse Time Migration (RTM) based subsurface imaging algorithm. Since concrete is heterogeneous, an unfocused ultrasonic field will be randomly scattered by the aggregates, thereby masking information about damage(s). A focused ultrasonic field, on the other hand, increases the possibility of detection of an anomaly due to enhanced amplitude of the incident field in the focal region. Further, the RTM based reconstruction using scattered focused field data is capable of creating clear images of the inspected region of interest. Since scattering of a focused field by a damaged rebar differs qualitatively from that of an undamaged rebar, distinct images of damaged and undamaged situations are obtained in the RTM generated images. This is demonstrated with both numerical and experimental investigations. The total scattered field, acquired on the surface of the concrete medium, is used as input for the RTM algorithm to generate the subsurface image that helps to identify the damage. The proposed technique, therefore, has some advantage since knowledge about the undamaged scenario for the concrete medium is not necessary to assess its integrity.

  3. 3D topographic correction of the BSR heat flow and detection of focused fluid flow

    NASA Astrophysics Data System (ADS)

    He, Tao; Li, Hong-Lin; Zou, Chang-Chun

    2014-06-01

    The bottom-simulating reflector (BSR) is a seismic indicator of the bottom of a gas hydrate stability zone. Its depth can be used to calculate the seafloor surface heat flow. The calculated BSR heat flow variations include disturbances from two important factors: (1) seafloor topography, which focuses the heat flow over regions of concave topography and defocuses it over regions of convex topography, and (2) the focused warm fluid flow within the accretionary prism coming from depths deeper than BSR. The focused fluid flow can be detected if the contribution of the topography to the BSR heat flow is removed. However, the analytical equation cannot solve the topographic effect at complex seafloor regions. We prove that 3D finite element method can model the topographic effect on the regional background heat flow with high accuracy, which can then be used to correct the topographic effect and obtain the BSR heat flow under the condition of perfectly flat topography. By comparing the corrected BSR heat flow with the regional background heat flow, focused fluid flow regions can be detected that are originally too small and cannot be detected using present-day equipment. This method was successfully applied to the midslope region of northern Cascadia subducting margin. The results suggest that the Cucumber Ridge and its neighboring area are positive heat flow anomalies, about 10%-20% higher than the background heat flow after 3D topographic correction. Moreover, the seismic imaging associated the positive heat flow anomaly areas with seabed fracture-cavity systems. This suggests flow of warm gas-carrying fluids along these high-permeability pathways, which could result in higher gas hydrate concentrations.

  4. Diffraction analysis and evaluation of several focus- and track-error detection schemes for magneto-optical disk systems

    NASA Technical Reports Server (NTRS)

    Bernacki, Bruce E.; Mansuripur, M.

    1992-01-01

    A commonly used tracking method on pre-grooved magneto-optical (MO) media is the push-pull technique, and the astigmatic method is a popular focus-error detection approach. These two methods are analyzed using DIFFRACT, a general-purpose scalar diffraction modeling program, to observe the effects on the error signals due to focusing lens misalignment, Seidel aberrations, and optical crosstalk (feedthrough) between the focusing and tracking servos. Using the results of the astigmatic/push-pull system as a basis for comparison, a novel focus/track-error detection technique that utilizes a ring toric lens is evaluated as well as the obscuration method (focus error detection only).

  5. Neuronavigation-guided focused ultrasound-induced blood-brain barrier opening: A preliminary study in swine

    NASA Astrophysics Data System (ADS)

    Liu, Hao-Li; Tsai, Hong-Chieh; Lu, Yu-Jen; Wei, Kuo-Chen

    2012-11-01

    FUS-induced BBB opening is a promising technique for noninvasive and local delivery of drugs into the brain. Here we propose the novel use of a neuronavigation system to guide the FUS-induced BBB opening procedure, and investigate its feasibility in vivo in large animals. We developed an interface between the neuronavigator and FUS to allow guidance of the focal energy produced by the FUS transducer. The system was tested in 29 pigs by more than 40 sonication procedures and evaluated by MRI. Gd-DTPA concentration was quantitated in vivo by MRI R1 relaxometry and compared by ICP-OES assay. Brain histology after FUS exposure was investigated by HE and TUNEL staining. Neuronavigation could successfully guide the focal beam with comparable precision to neurosurgical stereotactic procedures (2.3 ± 0.9 mm). FUS pressure of 0.43 MPa resulted in consistent BBB-opening. Neuronavigation-guided BBB-opening increased Gd-DTPA deposition by up to 1.83 mM (140% increase). MR relaxometry demonstrated high correlation to ICP-OES measurements (r2 = 0.822), suggesting that Gd-DTPA deposition can be directly measured by imaging. Neuronavigation could provide sufficient precision for guiding FUS to temporally and locally open the BBB. Gd-DTPA deposition in the brain could be quantified by MR relaxometry, providing a potential tool for the in vivo quantification of therapeutic agents in CNS disease treatment.

  6. Detection of Cracks at Welds in Steel Tubing Using Flux Focusing Electromagnetic Probe

    NASA Technical Reports Server (NTRS)

    Wincheski, Buzz; Fulton, Jim; Nath, Shridhar; Simpson, John; Namkung, Min

    1994-01-01

    The inspection of weldments in critical pressure vessel joints is a major concern in the nuclear power industry. Corrosive environments can speed the fatigue process and access to the critical area is often limited. Eddy current techniques have begun to be used to help overcome these obstacles [1]. As direct contact and couplants are not required, remote areas can be inspected by simply snaking an eddy current coil into the intake tube of the vessel. The drawback of the eddy current method has been the high sensitivity to small changes in the conductivity and permeability of the test piece which are known to vary at weldments [1]. The flaw detection mechanism of the flux focusing electromagnetic probe can help alleviate these difficulties and provide a unique capability for detecting longitudinal fatigue cracks in critical tube structures. The Flux Focusing Electromagnetic Flaw Detector, originally invented for the detection of fatigue and corrosion damage in aluminum plates [2-3], has been adapted for use in testing steel tubing for longitudinal fatigue cracks. The modified design allows for the probe to be placed axisymmetrically into the tubing, inducing eddy currents in the tube wall. The pickup coil of the probe is fixed slightly below the primary windings and is rotated 90 so that its axis is normal to the tube wall. The magnetic flux of the primary coil is focused through the use of ferromagnetic material so that in the absence of fatigue damage there will be no flux linkage with the pickup coil. The presence of a longitudinal fatigue crack will cause the eddy currents induced in the tube wall to flow around the flaw and directly under the pickup coil. The magnetic field associated with these currents will then link the pickup coil and an unambiguous increase in the output voltage of the probe will be measured. The use of the flux focusing electromagnetic probe is especially suited for the detection of flaws originating at or near tube welds. The probe is

  7. Line-focusing electromagnetic acoustic transducers for the detection of slit defects.

    PubMed

    Ogi, H; Hirao, M; Ohtani, T

    1999-01-01

    This paper describes the design principles of a line-focusing electromagnetic acoustic transducer (LF-EMAT) and the results of a feasibility test for detecting slit-type defects in metals. The LF-EMAT excites shear vertical (SV) elastic waves and focuses them to a line in a metal body. It consists of a permanent magnet block and a meanderline coil, whose spacing is continuously varied so that the excited SV waves become coherent on a focal line after traveling oblique paths. The measured directivity of generation and reception show a sharp peak at the designed focal line. The LF-EMATs are then applied to detecting slit defects in the bottom surface of steel blocks, on which the focal lines are located. Portions of the scattered defect signals are received by the same EMAT. When operated at 4 MHz, the LF-EMATs are capable of detecting slits deeper than 0.05 mm. The sensitivity decreases with liftoff and the LF-EMATs are usable with liftoff up to 0.6 mm. PMID:18238430

  8. Remote Detection of Concealed Radioactive Materials by Using Focused Powerful Terahertz Radiation

    NASA Astrophysics Data System (ADS)

    Nusinovich, Gregory S.

    2016-06-01

    This review paper summarizes the results of studies of a novel concept of the remote detection of concealed radioactive materials by using focused high-power terahertz (THz) radiation. The concept is based on the known fact that the ambient electron density in air is low (one to three free electrons per cubic centimeter). These electrons can serve as seed electrons from which an avalanche breakdown in strong electromagnetic fields starts. When a powerful THz radiation is focused in a small spot, the breakdown-prone volume can be much smaller than a cubic centimeter. So, the probability of having some free electrons in this volume and, hence, the probability of breakdown are low in the absence of additional sources of air ionization. However, in the vicinity of radioactive materials (10-20 m), the electron density can be higher, and, hence, there are always some seed free electrons from which the avalanche ionization will start. Thus, the breakdown rate in this case can be close to 100 %. Realization of this concept requires studies of various physical and technical issues. First, it is necessary to develop a high-power source of (sub-) THz radiation whose power, frequency, and pulse duration are sufficient for realizing this goal. Second, it is necessary to analyze numerous issues important for realizing this concept. Among these issues are (a) enhancement of the ionization level of air molecules in the presence of hidden radioactive materials, (b) estimating the minimum detectable mass of radioactive material, (c) formation of breakdown-prone volumes in focused THz wave beams, and (d) effect of atmospheric conditions on the propagation and focusing of THz wave beams and on the optimal location of the breakdown-prone volume between a container with hidden radioactive material and a THz antenna. The results of these studies are described below.

  9. Magnetic focusing immunosensor for the detection of Salmonella typhimurium in foods

    NASA Astrophysics Data System (ADS)

    Pivarnik, Philip E.; Cao, He; Letcher, Stephen V.; Pierson, Arthur H.; Rand, Arthur G.

    1999-01-01

    From 1988 through 1992 Salmonellosis accounted for 27% of the total reported foodborne disease outbreaks and 57% of the outbreaks in which the pathogen was identified. The prevalence of Salmonellosis and the new requirements to monitor the organism as a marker in pathogen reduction programs will drive the need for rapid, on-site testing. A compact fiber optic fluorometer using a red diode laser as an excitation source and fiber probes for analyte detection has been constructed and used to measure Salmonella. The organisms were isolated with anti-Salmonella magnetic beads and were labeled with a secondary antibody conjugated to a red fluorescent dye. The response of the system was proportional to the concentration of Salmonella typhimurium from 3.2 X 105 colony forming units (CFU)/ml to 1.6 X 107 CFU/ml. The system was developed to utilize a fiber-optic magnetic focusing problem that attracted the magnetic microspheres to the surface of a sample chamber directly in front of the excitation and emission fibers. The signal obtained from a homogenous suspension of fluorescent magnetic microspheres was 9 to 10 picowatts. After focusing, the signal from the fluorescent labeled magnetic microspheres increased to 200 picowatts, approximately 20 times greater than the homogeneous suspension. The magnetic focusing assay detected 1.59 X 105 colony forming units/ml of Salmonella typhimurium cultured in growth media. The process of magnetic focusing in front of the fibers has the potential to reduce the background fluorescence from unbound secondary antibodies, eliminating several rinsing steps, resulting in a simple rapid assay.

  10. Flexible Integration of Both High Imaging Resolution and High Power Arrays for Ultrasound-Induced Thermal Strain Imaging (US-TSI)

    PubMed Central

    Stephens, Douglas N.; Mahmoud, Ahmed M.; Ding, Xuan; Lucero, Steven; Dutta, Debaditya; Yu, Francois T.H.; Chen, Xucai

    2013-01-01

    Ultrasound-induced thermal strain imaging (US-TSI) for carotid artery plaque detection requires both high imaging resolution (<100 μm) and sufficient US induced heating to elevate the tissue temperature (~1-3°C within 1-3 cardiac cycles) in order to produce a noticeable change in sound speed in the targeted tissues. Since the optimization of both imaging and heating in a monolithic array design is particularly expensive and inflexible, a new integrated approach is presented that utilizes independent ultrasound arrays to meet the requirements for this particular application. This work demonstrates a new approach in dual-array construction. A 3D printed manifold was built to support both a high resolution 20 MHz commercial imaging array and 6 custom heating elements operating in the 3.5-4 MHz range. For the application of US-TSI on carotid plaque characterization, the tissue target site is 20 to 30 mm deep, with a typical target volume of 2 mm (elevation) × 8 mm (azimuthal) × 5 mm (depth). The custom heating array performance was fully characterized for two design variants (flat and spherical apertures), and can easily deliver 30 W of total acoustic power to produce intensities greater than 15 W/cm2 in tissue target region. PMID:24297029

  11. Capillary isoelectric focusing of proteins and microorganisms in dynamically modified fused silica with UV detection.

    PubMed

    Horká, Marie; Růzicka, Filip; Horký, Jaroslav; Holá, Veronika; Slais, Karel

    2006-09-01

    We suggest a method for the reproducible and efficient capillary isoelectric focusing of proteins and microorganisms in the pH gradient 3-10. The method involves the segmental injection of the simple ampholytes, the solution of the selected electrolytes, and the sample mixture of bioanalytes and carrier ampholytes to the fused silica capillaries dynamically modified by poly(ethylene glycol), PEG 4000, which is added to the catholyte, the anolyte and injected solutions. In order to receive the reproducible results, the capillaries were rinsed by the mixture of acetone/ethanol between analyses. For the tracing of the pH gradients the low-molecular-mass pI markers were used. The simple proteins and the mixed cultures of microorganisms, Saccharomyces cerevisiae CCM 8191, Escherichia coli CCM 3954, Candida albicans CCM 8180, Candida parapsilosis, Candida krusei, Staphylococcus aureus, Streptococcus agalactiae CCM 6187, Enterococcus faecalis CCM 4224, Staphylococcus epidermidis CCM 4418 and Stenotrophomonas maltophilia, were focused and separated by the method suggested. The minimum detectable number of microbial cells was 5x10(2) to 1x10(3) with on-column UV detection at 280 nm.

  12. Detection and differentiation of microbial siderophores by isoelectric focusing and chrome azurol S overlay.

    PubMed

    Koedam, N; Wittouck, E; Gaballa, A; Gillis, A; Höfte, M; Cornelis, P

    1994-10-01

    Siderophores are microbial, low molecular weight iron-chelating compounds. Fluorescent Pseudomonads produce different, strain-specific fluorescent siderophores (pyoverdines) as well as non-fluorescent siderophores in response to low iron conditions. We present an isoelectric focusing method applicable to unpurified as well as to purified pyoverdine samples where the fluorescent siderophores are visualized under UV illumination. Siderophores from different Pseudomonas sp., amongst which are P. aeruginosa, P. fluorescens and P. putida, including egg yolk, rhizospheric and clinical isolates as well as some derived Tn5 mutants were separated by this technique. Different patterns could be observed for strains known to produce different siderophores. The application of the chrome azurol S assay as a gel overlay further allows immediate detection of non-fluorescent siderophores or possibly degradation products with residual siderophore activity. The method was also applied to other microbial siderophores such as deferrioxamine B. PMID:7812113

  13. Radially Focused Eddy Current Sensor for Detection of Longitudinal Flaws in Metallic Tubes

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A. (Inventor); Simpson, John W. (Inventor); Fulton, James P. (Inventor); Nath, Shridhar C. (Inventor); Todhunter, Ronald G. (Inventor); Namkung, Min (Inventor)

    1999-01-01

    A radially focused eddy current sensor detects longitudinal flaws in a metal tube. A drive coil induces eddy currents within the wall of the metal tube. A pick-up cod is spaced apart from the drive coil along the length of the metal tube. The pick@up coil is positioned with one end thereof lying adjacent the wall of the metal tube such that the pick-up coil's longitudinal axis is perpendicular to the wall of the metal tube. To isolate the pick-up coil from the magnetic flux of the drive coil and the flux from the induced eddy currents. except the eddy currents diverted by a longitudinal flaw. an electrically conducting material high in magnetic permeability surrounds all of the pick-up coil except its one end that is adjacent the walls of the metal tube. The electrically conducting material can extend into and through the drive coil in a coaxial relationship therewith.

  14. Straightforward production of encoded microbeads by Flow Focusing: potential applications for biomolecule detection.

    PubMed

    Gañán-Calvo, A M; Martín-Banderas, L; González-Prieto, R; Rodríguez-Gil, A; Berdún-Alvarez, T; Cebolla, A; Chávez, S; Flores-Mosquera, M

    2006-10-31

    Fluorescently encoded polymeric microparticles are acquiring great importance in the development of simultaneous multianalyte screening assays. We have developed a very versatile and straightforward method for the production of dye-labeled microparticles with a very reproducible size distribution and freely-chosen and discernible fluorescent properties. Our method combines Flow Focusing technology with a solvent evaporation/extraction procedure in a single step, yielding spherical, non-aggregate and non-porous particles. We have designed a multi-coloured bead array which includes the possibility of modifying the surface properties of the microparticles, which offer excellent properties for covalent attachment of biomolecules such as peptides, oligonucleotides, proteins, etc. We also show the potential of the fluorescently labeled microspheres for the detection of biomolecule (peptides and oligonucelotides) interactions using flow cytometry.

  15. Evaluation of Ultrasound-Induced Damage to Escherichia coli and Staphylococcus aureus by Flow Cytometry and Transmission Electron Microscopy

    PubMed Central

    Li, Jiao; Ahn, Juhee; Liu, Donghong; Chen, Shiguo; Ye, Xingqian

    2016-01-01

    As a nonthermal sterilization technique, ultrasound has attracted great interest in the field of food preservation. In this study, flow cytometry and transmission electron microscopy were employed to investigate ultrasound-induced damage to Escherichia coli and Staphylococcus aureus. For flow cytometry studies, single staining with propidium iodide (PI) or carboxyfluorescein diacetate (cFDA) revealed that ultrasound treatment caused cell death by compromising membrane integrity, inactivating intracellular esterases, and inhibiting metabolic performance. The results showed that ultrasound damage was independent of initial bacterial concentrations, while the mechanism of cellular damage differed according to the bacterial species. For the Gram-negative bacterium E. coli, ultrasound worked first on the outer membrane rather than the cytoplasmic membrane. Based on the double-staining results, we inferred that ultrasound treatment might be an all-or-nothing process: cells ruptured and disintegrated by ultrasound cannot be revived, which can be considered an advantage of ultrasound over other nonthermal techniques. Transmission electron microscopy studies revealed that the mechanism of ultrasound-induced damage was multitarget inactivation, involving the cell wall, cytoplasmic membrane, and inner structure. Understanding of the irreversible antibacterial action of ultrasound has great significance for its further utilization in the food industry. PMID:26746712

  16. Controlled fabrication of nanopores using a direct focused ion beam approach with back face particle detection

    NASA Astrophysics Data System (ADS)

    Patterson, N.; Adams, D. P.; Hodges, V. C.; Vasile, M. J.; Michael, J. R.; Kotula, P. G.

    2008-06-01

    We report a direct, ion drilling technique that enables the reproducible fabrication and placement of nanopores in membranes of different thickness. Using a 30 keV focused Ga ion beam column combined with an in situ, back face, multi-channelplate particle detector, nanopores are sputtered in Si3N4 and W/Si3N4 to have diameters as small as 12 nm. Transmission electron microscopy shows that focused ion beam-drilled holes are near-conical with the diameter decreasing from entry to exit side. By monitoring the detector signal during ion exposure, the drilled hole width can be minimized such that the exit-side diameter is smaller than the full width at half-maximum of the nominally Gaussian-shaped incident beam. Judicious choice of the beam defining aperture combined with back face particle detection allows for reproducible exit-side hole diameters between 18 and 100 nm. The nanopore direct drilling technique does not require potentially damaging broad area exposure to tailor hole sizes. Moreover, this technique successfully achieves breakthrough despite the effects of varying membrane thickness, redeposition, polycrystalline grain structure, and slight ion beam current fluctuations.

  17. Controlled fabrication of nanopores using a direct focused ion beam approach with back face particle detection.

    PubMed

    Patterson, N; Adams, D P; Hodges, V C; Vasile, M J; Michael, J R; Kotula, P G

    2008-06-11

    We report a direct, ion drilling technique that enables the reproducible fabrication and placement of nanopores in membranes of different thickness. Using a 30 keV focused Ga ion beam column combined with an in situ, back face, multi-channelplate particle detector, nanopores are sputtered in Si(3)N(4) and W/Si(3)N(4) to have diameters as small as 12 nm. Transmission electron microscopy shows that focused ion beam-drilled holes are near-conical with the diameter decreasing from entry to exit side. By monitoring the detector signal during ion exposure, the drilled hole width can be minimized such that the exit-side diameter is smaller than the full width at half-maximum of the nominally Gaussian-shaped incident beam. Judicious choice of the beam defining aperture combined with back face particle detection allows for reproducible exit-side hole diameters between 18 and 100 nm. The nanopore direct drilling technique does not require potentially damaging broad area exposure to tailor hole sizes. Moreover, this technique successfully achieves breakthrough despite the effects of varying membrane thickness, redeposition, polycrystalline grain structure, and slight ion beam current fluctuations. PMID:21825787

  18. High-efficiency molecular counting in solution: Single-molecule detection in electrodynamically focused microdroplet streams

    SciTech Connect

    Lermer, N.; Barnes, M.D.; Kung, C.Y.; Whitten, W.B.; Ramsey, J.M.

    1997-06-01

    We report fluorescence detection of individual rhodamine 6G molecules using a linear quadrupole to focus streams of microdroplets through the waist of a counterpropagating cw Ar{sup +} laser. Since the terminal velocity scales as the square of the droplet diameter, the droplet-laser interaction time was `tunable` between 5 and 200 ms by using water samples spiked with a small, variable (2-5% v/v) amount of glycerol. Fluorescence bursts from droplets containing single molecules were clearly distinguished from the blanks in real time with an average signal-to-noise ratio of about 10, limited primarily by photobleaching and droplet size fluctuations (<1%). The volume throughput rates associated with this approach (approx. 10 pL/s) are roughly 10{sup 3} higher than those associated with particle levitation techniques, with minimal sacrifice in sensitivity. Total molecular detection efficiencies of about 80% (at >99% confidence) were obtained for 100 and 15 fM rhodamine 6G solutions, in good agreement with detailed theoretical calculations and statistical limitations. 39 refs., 7 figs., 1 tab.

  19. Corrosion Detection in Airframes Using a New Flux-Focusing Eddy Current Probe

    NASA Technical Reports Server (NTRS)

    Fulton, James P.; Wincheski, Buzz; Nath, Shridhar; Namkung, Min

    1994-01-01

    A new flux-focusing eddy current probe was recently developed at NASA Langley Research Center. The new probe is similar in design to a reflection type eddy current probe, but is unique in that it does not require the use of an impedance bridge for balancing. The device monitors the RMS output voltage of a pickup coil and, as a result, is easier to operate and interpret than traditional eddy current instruments. The unique design feature of the probe is a ferromagnetic cylinder, typically 1020 steel, which separates a concentrically positioned drive and pickup coil. The increased permeability of the steel causes the magnetic flux produced by the drive coil to be focused in a ring around the pickup coil. At high frequencies the eddy currents induced in both the sample and the cylinder allow little or no flux to link with the pickup coil. This results in a self-nulling condition which has been shown to be useful for the unambiguous detection of cracks in conducting materials. As the frequency is lowered the flux produced by the drive coil begins to link with the pickup coil causing an output which, among other things, is proportional to the thickness of the test specimen. This enables highly accurate measurements of the thickness of conducting materials and helps to facilitate the monitoring of thickness variations in a conducting structure such as an aircraft fuselage. Under ideal laboratory conditions the probe can sense thickness changes on the order of 1% as illustrated. However, this is highly dependent upon the thickness, and the geometric complexity of the sample being tested and for practical problems the sensitivity is usually much less. In this presentation we highlight some of the advantages and limitations in using the probe to inspect aircraft panels for corrosion and other types of material nonuniformities. In particular, we present preliminary results which illustrate the probes capabilities for detecting first and second layer corrosion in aircraft

  20. SEIS/INSIGHT and Mars seismology: Development status and focus on the Impact detection

    NASA Astrophysics Data System (ADS)

    Lognonne, Philippe; Banerdt, William; Pike, Tom; Giardini, Domenico; Christensen, Ulli; Banfield, Don; Mimoun, David; Laudet, Philippe; de Raucourt, Sebastien; Bierwirth, Marco; Zweifel, Peter; Calcutt, Simon; Hurst, Ken; Bruce, Carl

    2014-05-01

    The INSIGHT NASA Discovery mission will deploy in September 2016 a 3 axis Very Broad band seismometer and a 3 axis SP seismometer, as well as other instruments enabling the installation of a complete geophysical observatory recording seismic, heat flow, magnetic and geodetic signals, in addition to atmospheric wind, pressure and temperature. We first present the science goals status of the SEIS experiment and its development status. The SEIS sensor assembly, which contains both the VBB and SP seismometer, will be deployed on the Martian ground by a robotic arm from a Phoenix-type lander platform and protected by a wind and thermal shield. The wind and thermal shield, a vacuum sphere for VBBs and a passive compensation system will achieve a very high protection of the seismometers against temperature and pressure variations, allowing the sensor to operate in the rough Martian thermal environment while reaching a detection threshold below 10^(-9) m/s/s Hz^(-1/2) in the VBB bandwidth and 10^(-8) m/s/s Hz^(-1/2) for the SP. A levelling system will allow the VBB to operate, while providing to both seismometer the best possible mechanical coupling with the ground motion. The SEIS instrument will be provided by CNES, which will coordinate a wide set of international contributors from the Institut de Physique du Globe de Paris, the Imperial College from London and the Open University, the Max-Planck Insitute of Lindau, the École polytechnique fédérale de Zurich (ETHZ), the Jet Propulsion Laboratory and the Institut de l'Aéronautique et de l'Espace from Toulouse. We then illustrate the science goals by a focus on the capability of INSIGHT to detect either seismic or acoustic signals from impacts, with both the seismometers and the pressure sensor, and present both amplitude and occurrence expectation, based on comparative modeling between Mars, Earth and the Moon.

  1. Detection and Modeling of the Tsunami Generated by 2013 Okhotsk Deep Focus Earthquake

    NASA Astrophysics Data System (ADS)

    Williamson, A.; Newman, A. V.; Okal, E. A.

    2015-12-01

    The May 24, 2013 moment magnitude (MW) 8.3 Sea of Okhotsk deep earthquake is the largest deep focused earthquake on record. This event is the only great (Mw > 8.0) earthquake in the past two decades to rupture at a depth greater than 300 km and is the only deep earthquake to be detected by modern geodetic tools such as DART pressure sensors, continuous GPS, and GRACE. Continuous GPS stations along the Kamchatka Peninsula and Kuril Islands recorded sub-centimeter static displacements including subsidence across the peninsula, inferring a spatially extensive region of uplift within the Sea of Okhotsk likely generating a low-amplitude, but long-wavelength tsunami wave. We use water column height changes recorded at 10 regional DART pressure sensors, to evaluate the detectability and usability of these tsunami sensors in identifying tsunami waves from such deep earthquakes. Of the 10 sites, only 2 were triggered by the event, enabling capture of high-rate (one sample per minute) pressure data. The remaining sites reported at the background rate of 15 minutes per sample. From these sensors we observed sub-centimeter tsunami waves, in general agreement with synthetics computed using normal mode theory, following the framework of Ward (1980). Additionally, despite remaining at the low-frequency background rate, we were able to identify wave periods around 9000 s across multiple DART stations. We will report on our observations of the long-period tsunami waves from these sensors, and our analysis of how they compare to both reported, and our best-fit determination of the Okhotsk earthquake focal mechanism and location.

  2. Genetically Controlled Variation of "Acid" β-Galactosidase Detected in Rattus norvegicus by Isoelectric Focusing

    PubMed Central

    Douglas, Tommy C.; Kimmel, Kathryn A.; Dawson, Patti E.

    1982-01-01

    Two genetically variant forms of rat "acid" β-galactosidase were found to differ in isoelectric point and pH dependence, but not in thermostability or sensitivity to inhibition by p-mercuribenzoate (PMB). The results of two backcrosses and an intercross indicated that the isoelectric focusing phenotypes are controlled by two codominant alleles at a single autosomal locus, for which we propose the name Glb-1. No significant linkage between Glb-1 and albino (LG I), brown (LG II), or hooded (LG VI) was observed. Strain-specific differences in total levels of kidney β-galactosidase were detected, but it is not yet known whether the variation is controlled by genes linked to Glb-1. Experiments in which organ homogenates were incubated with neuraminidase indicated that the genetically variant forms do not result from differences in sialylation, though sialylation does appear to be largely responsible for the presence of multiple bands within each phenotype and for differences in the banding patterns of β-galactosidases derived from different organs. The β-galactosidase present in the bands used for Glb-1 typing resembles human GM1 gangliosidase (GLB1) with respect to pH optimum, substrate specificity, and susceptibility to inhibition by PMB. It also appears that Glb-1 is homologous with the Bgl-e locus of the mouse. In rats as in mice the genetically variant bands of β-galactosidase are active at acid pH and have relatively high isoelectric points. In both species these bands are readily detectable in kidney homogenates, and can be revealed in homogenates of liver or spleen following treatment with neuraminidase. The presence of the same β-galactosidase bands in homogenates of rat kidney and small intestine as well as in neuraminidase-treated homogenates of liver and spleen suggests that the Glb-1 variants differ by one or more point mutations in the structural gene for "acid" β-galactosidase. PMID:6811372

  3. The role of heating, cavitation and acoustic streaming in mediating ultrasound-induced changes of TGF-beta gene expression in bone cells

    NASA Astrophysics Data System (ADS)

    Harle, J.; Mayia, F.

    2004-01-01

    This paper relates ultrasound-induced changes in bone cell function to quantitative data assessing the level of several interaction mechanisms within the exposure environment. Characterisation of ultrasound fields in terms of resultant levels of heating, cavitation and acoustic streaming may provide a novel means of accurately assessing the likelihood of biological effects in vitro.

  4. Ultrasound-induced controllable morphology and growth dimension in a dihydrazide-based self-assembly system.

    PubMed

    Zhang, Yan; Ding, Hao; Wu, Yangfang; Zhang, Chunxue; Bai, Binglian; Wang, Haitao; Li, Min

    2014-11-28

    We have demonstrated ultrasound-induced organogels based on twin-tapered dihydrazide derivatives, oxalyl acid N,N-di(3,4,5-trialkoxybenzoyl)hydrazide (FH-Tn). Ultrasound irradiation has been proved to influence gel properties at micro-levels. Different self-assembled structures from entangled fibers to tube-like structures and nanoparticles can be easily manipulated by tuning irradiation time and water bath temperature. FT-IR spectra exhibit weakened hydrogen bonding interactions, and XRD studies showed different packing modes before and after sonication. In addition, ultrasound can have effects on gel properties at macro-levels. Gels obtained from ultrasound treatment possess different wetting properties, relatively worse rheological properties and thermo-stability. Kinetic studies based on dynamic fluorescence spectra, rheological studies and theoretical calculations suggest that molecular aggregation mode differed from one-dimension to two-dimension for the gel after sonication.

  5. Computer-aided tissue characterization using ultrasound-induced thermal effects: analytical formulation and in-vitro animal study

    NASA Astrophysics Data System (ADS)

    Daoud, Mohammad I.; Mousavi, Parvin; Imani, Farhad; Rohling, Robert; Abolmaesumi, Purang

    2011-03-01

    Ultrasound radio-frequency (RF) time series analysis provides an effective tissue characterization method to differentiate between healthy and cancerous prostate tissues. In this paper, an analytical model is presented that partially describes the variations in tissue acoustic properties that accompany ultrasound RF time series acquisition procedures. These ultrasound-induced effects, which depend on tissue mechanical and thermophysical properties, are hypothesized to be among the major contributors to the tissue typing capabilities of the RF time series analysis. The model is used to derive two tissue characterization features. The two features are used with a support vector machine classifier to characterize three animal tissue types: chicken breast, bovine liver, and bovine steak. Accuracy values as high as 90% are achieved when the proposed features are employed to differentiate these tissue types. The proposed model may provide a framework to optimize the ultrasound RF time series analysis for future clinical procedures.

  6. Hand-held forward-looking focused array mine detection with plane wave excitation

    NASA Astrophysics Data System (ADS)

    Rappaport, Carey M.; Azevedo, Stephen G.; Rosenbury, Tom; Gough, Jamie; Jin, Dongping

    2000-08-01

    A novel handheld time-domain array GPR antipersonnel mine detection system prototype has been developed. Using an offset paraboloidal reflector antenna to collimate rays form an ultra-wideband feed, the transmitted microwave impulse is concentrated forward, in front of the antenna structure. The resulting wave is a non-uniform plane wave over the portion of ground be investigated, and is incident at 45 degrees to normal. As such, much of the ground reflect wave is directed further forward, away from the operator, the reflector, and the receiving antennas, thereby reducing clutter. However, the wave transmitted into the ground, which interacts with the target, tends to have significant backscatter returning toward the receiving antennas. These receiving antennas are configured in a 2 by 2 array to provide spatial focusing in both along and cross-track directions. This is accomplished by measuring and comparing the backscattered signal at each receiver in the narrow time window between the times when the ground reflected wave passes the receiver and before this wave re-reflects from the reflector components. 2D FDTD simulation of this parabolic reflector transmitter indicates that it generates a beam with a non-uniform planar wavefront, which scatters form rough ground primarily in the forward direction. The wave transmitted into the ground is also planar, propagating at the angle of refraction, and scattering fairly isotropically from a small penetrable target. This system has been built and tested at LLNL, using a very narrow pulse shape. LLNL's Micro-Impulse Radar (MIR) and custom-built wideband antenna elements operate in the 1.5 to 5 GHz range. One particular advantage of using the MIR module is its low cost: an important feature for mine detectors used in developing countries. Preliminary measured data indicates that the surface clutter is indeed reduced relative to the target signal, and that small non-metallic anti-personnel mines can be reliably detected at

  7. Capillary isoelectric focusing and fluorometric detection of proteins and microorganisms dynamically modified by poly(ethylene glycol) pyrenebutanoate.

    PubMed

    Horka, Marie; Ruzicka, Filip; Horký, Jaroslav; Holá, Veronika; Slais, Karel

    2006-12-15

    The nonionogenic pyrene-based tenside, poly(ethylene glycol) pyrenebutanoate, was prepared and applied in capillary isoelectric focusing with fluorometric detection. This dye was used here as a buffer additive in capillary isoelectric focusing for a dynamic modification of the sample of proteins and microorganisms. The values of the isoelectric points of the labeled bioanalytes were calculated with use of the fluorescent pI markers and were found comparable with pI of the native compounds. The mixed cultures of proteins and microorganisms, Escherichia coli CCM 3954, Staphylococcus epidermidis CCM 4418, Proteus vulgaris, Enterococcus faecalis CCM 4224, and Stenotrophomonas maltophilia, the strains of the yeast cells, Candida albicans CCM 8180, Candida krusei, Candida parapsilosis, Candida glabrata, Candida tropicalis, and Saccharomyces cerevisiae were reproducibly focused and separated by the suggested technique. Using UV excitation for the on-column fluorometric detection, the minimum detectable amount was down to 10 cells injected on the separation capillary.

  8. In-situ characterization of nanoparticle beams focused with an aerodynamic lens by Laser-Induced Breakdown Detection.

    PubMed

    Barreda, F-A; Nicolas, C; Sirven, J-B; Ouf, F-X; Lacour, J-L; Robert, E; Benkoula, S; Yon, J; Miron, C; Sublemontier, O

    2015-01-01

    The Laser-Induced Breakdown Detection technique (LIBD) was adapted to achieve fast in-situ characterization of nanoparticle beams focused under vacuum by an aerodynamic lens. The method employs a tightly focused, 21 μm, scanning laser microprobe which generates a local plasma induced by the laser interaction with a single particle. A counting mode optical detection allows the achievement of 2D mappings of the nanoparticle beams with a reduced analysis time thanks to the use of a high repetition rate infrared pulsed laser. As an example, the results obtained with Tryptophan nanoparticles are presented and the advantages of this method over existing ones are discussed. PMID:26498694

  9. In-situ characterization of nanoparticle beams focused with an aerodynamic lens by Laser-Induced Breakdown Detection

    PubMed Central

    Barreda, F.-A.; Nicolas, C.; Sirven, J.-B.; Ouf, F.-X.; Lacour, J.-L.; Robert, E.; Benkoula, S.; Yon, J.; Miron, C.; Sublemontier, O.

    2015-01-01

    The Laser-Induced Breakdown Detection technique (LIBD) was adapted to achieve fast in-situ characterization of nanoparticle beams focused under vacuum by an aerodynamic lens. The method employs a tightly focused, 21 μm, scanning laser microprobe which generates a local plasma induced by the laser interaction with a single particle. A counting mode optical detection allows the achievement of 2D mappings of the nanoparticle beams with a reduced analysis time thanks to the use of a high repetition rate infrared pulsed laser. As an example, the results obtained with Tryptophan nanoparticles are presented and the advantages of this method over existing ones are discussed. PMID:26498694

  10. In-situ characterization of nanoparticle beams focused with an aerodynamic lens by Laser-Induced Breakdown Detection.

    PubMed

    Barreda, F-A; Nicolas, C; Sirven, J-B; Ouf, F-X; Lacour, J-L; Robert, E; Benkoula, S; Yon, J; Miron, C; Sublemontier, O

    2015-10-26

    The Laser-Induced Breakdown Detection technique (LIBD) was adapted to achieve fast in-situ characterization of nanoparticle beams focused under vacuum by an aerodynamic lens. The method employs a tightly focused, 21 μm, scanning laser microprobe which generates a local plasma induced by the laser interaction with a single particle. A counting mode optical detection allows the achievement of 2D mappings of the nanoparticle beams with a reduced analysis time thanks to the use of a high repetition rate infrared pulsed laser. As an example, the results obtained with Tryptophan nanoparticles are presented and the advantages of this method over existing ones are discussed.

  11. A focus on microfluidics and nanotechnology approaches for the ultra sensitive detection of microRNA.

    PubMed

    Lingam, Swathi; Beta, Madhu; Dendukuri, Dhananjay; Krishnakumar, Subramanian

    2014-01-01

    MicroRNAs are small RNAs that are deregulated under disease conditions. This allows them to be used as biomarkers for disease diagnosis. Recently, such microRNAs are serving as non- invasive blood based biomarkers due to ease of detection, and high stability at room temperature in biofluids. In view of these advancements in biomarker research, efficient miRNA detection at the femtomolar level is important. MiRNA detection techniques to date include Northern blotting, real time PCR and microarray technology. While these are efficient techniques, they cannot detect very low miRNA levels, and have questionable specificity. This review describes nanotechnology, microfluidics and liquid phase miRNA detection techniques that are highly sensitive and specific. With some sophistication, some of these techniques can be used as point of care devices to rapidly detect low level miRNA in patient clinical samples to aid disease diagnosis and prognosis.

  12. Focus detection in digital holography by cross-sectional images of propagating waves

    NASA Astrophysics Data System (ADS)

    Özcan, Meriç

    2014-02-01

    In digital holography, computing a focused image of an object requires a prior knowledge of the distance of the object from the camera. When this distance is not known, it is necessary to repeat the image reconstruction at a range of distances followed by evaluation of each image with a sharpness metric to determine the in-focus distance of the object. Here, we present a method to nd the focus distance by processing the image transverse to the object plane instead of the processing in the image plane as it is usually done. Since the reconstructed hologram image is spatially symmetric around the focus point along the propagation axis, simply nding the symmetry points in the image cross-section speci es the focus location, and no other sharpness metrics are necessary to use. Also with this method, it is possible to nd the focus distances of multiple objects simultaneously, including the phase only objects without any staining. We will present the simulations and the experimental results obtained by a digital holographic microscope.

  13. A Distance Measure for Attention Focusing and Anaomaly Detection in Systems Monitoring

    NASA Technical Reports Server (NTRS)

    Doyle, R. J.

    1994-01-01

    Any attempt to introduce automation into the monitoring of complex physical systems must start from a robust anomaly detection capability. This task is far from straightforward, for a single definition of what constitutes an anomaly is difficult to come by.

  14. Detection of high tritium activity on the central titanium electrode of a plasma focus device

    SciTech Connect

    Rout, R.K.; Spinivasan, M.; Shyam, A.; Chitra, V. )

    1991-03-01

    In this paper a 2-kJ Mather plasma focus device is used to deuterate the top end surface (or tip) of its central titanium electrode to investigate the occurrence of anomalous nuclear reactions in the context of the cold fusion phenomenon. The tip of the central titanium electrode is found to develop at least a few tens of microcuries of tritium after several plasma focus discharges. Neither the tritium impurity level in the deuterium gas used in the experiment nor the tritium branch of the d-d reactions that are known to occur in plasma focus devices can account for such activity in the electrode. Anomalous nuclear reactions in the deuterated titanium lattice appear to be the most probable source of this high activity.

  15. Ultrasound-induced hyperthermia for the spatio-temporal control of gene expression in bone repair

    NASA Astrophysics Data System (ADS)

    Wilson, Christopher; Padilla, Frédéric; Zhang, Man; Vilaboa, Nuria; Kripfgans, Oliver; Fowlkes, Brian; Franceschi, Renny

    2012-10-01

    Spatial and temporal control over the expression of growth/differentiation factors is of great interest for regeneration of bone, but technologies capable of providing tight and active control over gene expression remain elusive. We propose the use of focused ultrasound for the targeted activation of heat shock-sensitive expression systems in engineered bone. We report in vitro results with cells that express firefly luciferase (fLuc) under the control of a heat shock protein promoter. Cells were embedded in fibrin scaffolds and exposed to focused ultrasound, using a custom 3.3MHz transducer (focal length 4", f-number 1.33", focal dimension 1.2mm lateral FWHM) in CW mode for 2-20 minutes at intensities ISPTA=120-440 W/cm2. The kinetics of ultrasound-mediated activation of the cells was compared with that of strictly thermal activation. Bioluminescence imaging revealed fLuc expression in an area ≥2.5mm in diameter at the position of the ultrasound focus, and the diameter and intensity of the signal increased with the amplitude of the acoustic energy. We also found that ultrasound activated fLuc expression with substantially shorter exposures than thermal activation. Our results demonstrate the potential for focused ultrasound to selectively activate the expression of a gene of interest in an engineered tissue and suggest that focused ultrasound activates the heat shock pathway by a combination of thermal and non-thermal mechanisms.

  16. Detection of intrathecal immunoglobulin G synthesis by capillary isoelectric focusing immunoassay in oligoclonal band negative multiple sclerosis.

    PubMed

    Halbgebauer, Steffen; Huss, André; Buttmann, Mathias; Steinacker, Petra; Oeckl, Patrick; Brecht, Isabel; Weishaupt, Andreas; Tumani, Hayrettin; Otto, Markus

    2016-05-01

    Oligoclonal immunoglobulin G bands (OCBs) restricted to the cerebrospinal fluid indicate intrathecal inflammation. Using isoelectric focusing and immunoblotting, they are detected in about 95 % of patients with clinically definite multiple sclerosis (MS). To elucidate whether in the remaining 5 % OCBs are truly absent or alternatively missed due to insufficient sensitivity of the routine measurement, we employed a new, highly sensitive nanoscale method for OCB detection. Capillary isoelectric focusing followed by immunological detection served to analyze OCBs in 33 well-characterized OCB-negative and 10 OCB-positive MS patients as well as in 100 OCB-negative control patients with non-inflammatory neurological diseases and 30 OCB-positive control patients with inflammatory neurological diseases. We detected intrathecal immunoglobulin G production in 10 out of 33 MS patients (30 %), initially diagnosed as being OCB-negative, and in all 10 OCB-positive MS patients, but in only 3 out of 100 non-inflammatory neurological controls (3 %) and in 29 of 30 inflammatory neurological controls (97 %). At least about one-third of MS patients without intrathecal immunoglobulin G synthesis according to standard methods are OCB-positive. Advanced methods for OCB detection may increase the analytical sensitivity for detecting OCB in patients with MS who are OCB-negative according to current routine methods.

  17. Conceptual design and development of GEM based detecting system for tomographic tungsten focused transport monitoring

    NASA Astrophysics Data System (ADS)

    Chernyshova, M.; Czarski, T.; Malinowski, K.; Kowalska-Strzęciwilk, E.; Poźniak, K.; Kasprowicz, G.; Zabołotny, W.; Wojeński, A.; Kolasiński, P.; Mazon, D.; Malard, P.

    2015-10-01

    Implementing tungsten as a plasma facing material in ITER and future fusion reactors will require effective monitoring of not just its level in the plasma but also its distribution. That can be successfully achieved using detectors based on Gas Electron Multiplier (GEM) technology. This work presents the conceptual design of the detecting unit for poloidal tomography to be tested at the WEST project tokamak. The current stage of the development is discussed covering aspects which include detector's spatial dimensions, gas mixtures, window materials and arrangements inside and outside the tokamak ports, details of detector's structure itself and details of the detecting module electronics. It is expected that the detecting unit under development, when implemented, will add to the safe operation of tokamak bringing the creation of sustainable nuclear fusion reactors a step closer. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

  18. Capillary isoelectric focusing--useful tool for detection of the biofilm formation in Staphylococcus epidermidis.

    PubMed

    Ruzicka, Filip; Horka, Marie; Hola, Veronika; Votava, Miroslav

    2007-03-01

    The biofilm formation is an important factor of S. epidermidis virulence. Biofilm-positive strains might be clinically more important than biofilm-negative ones. Unlike biofilm-negative staphylococci, biofilm-positive staphylococci are surrounded with an extracellular polysaccharide substance. The presence of this substance on the surface can affect physico-chemical properties of the bacterial cell, including surface charge. 73 S. epidermidis strains were examined for the presence of ica operon, for the ability to form biofilm by Christensen test tube method and for the production of slime by Congo red agar method. Isoelectric points (pI) of these strains were determined by means of Capillary Isoelectric Focusing. The biofilm negative strains focused near pI value 2.3, while the pI values of the biofilm positive strains were near 2.6. Isoelectric point is a useful criterion for the differentiation between biofilm-positive and biofilm-negative S. epidermidis strains.

  19. Detection of Silver Nanoparticles inside Marine Diatom Thalassiosira pseudonana by Electron Microscopy and Focused Ion Beam

    PubMed Central

    Pascual García, César; Burchardt, Alina D.; Carvalho, Raquel N.; Gilliland, Douglas; C. António, Diana; Rossi, François; Lettieri, Teresa

    2014-01-01

    In the following article an electron/ion microscopy study will be presented which investigates the uptake of silver nanoparticles (AgNPs) by the marine diatom Thalassiosira pseudonana, a primary producer aquatic species. This organism has a characteristic silica exoskeleton that may represent a barrier for the uptake of some chemical pollutants, including nanoparticles (NPs), but that presents a technical challenge when attempting to use electron-microscopy (EM) methods to study NP uptake. Here we present a convenient method to detect the NPs interacting with the diatom cell. It is based on a fixation procedure involving critical point drying which, without prior slicing of the cell, allows its inspection using transmission electron microscopy. Employing a combination of electron and ion microscopy techniques to selectively cut the cell where the NPs were detected, we are able to demonstrate and visualize for the first time the presence of AgNPs inside the cell membrane. PMID:24797958

  20. Pre-history of planet detections: Focus on transits 1620 - 1995

    NASA Astrophysics Data System (ADS)

    Briot, D.; Schneider, J.; François, P.

    2015-10-01

    The discovery of 51 Peg b has been a wonderful scientific discovery, answering a multi-secular question and opening a extended new domain of astronomical research. We want to recall some old studies, some of them quite forgotten, which have used the same methods that those for planet detection, emphasizing transit method. In addition to an overview of planet search pre-history, some searchs for unknown planets in the Solar System since the seventeenth century will be evoked, as well as the search for exoplanet transits during the nineteenth and the twentieth century. The conclusion will be back to the future.

  1. Ipsi- and Contralateral Motor Response Using Ultrasound-induced Neurostimulation in Deeply Anesthetized Mice

    NASA Astrophysics Data System (ADS)

    Kamimura, Hermes; Wang, Shutao; Chen, Hong; Wang, Qi; Aurup, Christian; Fan, Kathtleen; Carneiro, Antonio; Konofagou, Elisa

    Ultrasound neurostimulation has been proven capable of eliciting motor responses. However, the studies in sedated rodents presented problems with target specificity due to the use of low ultrasound frequencies (<700 kHz). Here, we show that focused ultrasound (FUS) in mega-Hz range was able to evoke motor responses in mice under deep anesthesia. Contralateral movements of the hind limbs were observed when sonications were carried out at +2 mm of Lambda and ±2 mm lateral of midline in three mice. Moreover, stimulating other regions of the somatosensory and cerebellum induced trunk and ipsilateral limb movements in all six mice.

  2. Electrically neutral microheterogeneity of human plasma transthyretin (prealbumin) detected by isoelectric focusing in urea gradients.

    PubMed

    Altland, K; Winter, P; Sauerborn, M K

    1999-06-01

    Mutants of the human plasma transthyretin (TTR, prealbumin) have attracted interest due to their rather frequent association with the autosomal dominant disease familial amyloidotic polyneuropathy (FAP). Some three quarters of known TTR mutations produce electrically neutral amino acid substitutions undetectable via separation by charge. We have developed an electrophoretic procedure sensitive to differences in the stability of tetramers and monomers under partially denaturing conditions. The differential folding states were found to be fully reversible. Applying the procedure we found 14 electrically silent mutants of TTR among 2000 plasma samples from German donors. We demonstrate that the normal TTR monomer exists in different forms of variable stability and/or charge due to binding of sulfhydryls from plasma to the unique cysteine at position 10 of the primary structure as well as due to modification by treatment with an oxidant. We found that reduction of Cys10 increases the stability of the folded monomeric and tetrameric conformations. The conformational changes of TTR induced by isoelectric focusing in a urea gradient were found to be associated by a gain of three positive charge units. Using published crystallographic data we present structural sites in the TTR molecule which could explain the observed effects.

  3. PLLA nanofibrous paper-based plasmonic substrate with tailored hydrophilicity for focusing SERS detection.

    PubMed

    Shao, Jundong; Tong, Liping; Tang, Siying; Guo, Zhinan; Zhang, Han; Li, Penghui; Wang, Huaiyu; Du, Chang; Yu, Xue-Feng

    2015-03-11

    We report a new paper-based surface enhanced Raman scattering (SERS) substrate platform contributed by a poly(l-lactic acid) (PLLA) nanofibrous paper adsorbed with plasmonic nanostructures, which can circumvent many challenges of the existing SERS substrates. This PLLA nanofibrous paper has three-dimensional porous structure, extremely clean surface with good hydrophobicity (contact angle is as high as 133.4°), and negligible background interference under Raman laser excitation. Due to the strong electrostatic interaction between PLLA nanofiber and cetyltrimethylammonium bromide (CTAB) molecules, the CTAB-coated gold nanorods (GNRs) are efficiently immobilized onto the fibers. Such a hydrophobic paper substrate with locally hydrophilic SERS-active area can confine analyte molecules and prevent the random spreading of molecules. The confinement leads to focusing effect and the GNRs-PLLA SERS substrate is found to be highly sensitive (0.1 nM Rhodamine 6G and malachite green) and exhibit excellent reproducibility (∼8% relative standard deviation (RSD)) and long-term stability. Furthermore, it is also cost-efficient, with simple fabrication methodology, and demonstrates high sample collection efficiency. All of these benefits ensure that this GNRs-PLLA substrate is a really perfect choice for a variety of SERS applications. PMID:25697378

  4. Diagnostic Ultrasound Induced Inertial Cavitation to Non-Invasively Restore Coronary and Microvascular Flow in Acute Myocardial Infarction

    PubMed Central

    Xie, Feng; Gao, Shunji; Wu, Juefei; Lof, John; Radio, Stanley; Vignon, Francois; Shi, William; Powers, Jeffry; Unger, Evan; Everbach, E. Carr; Liu, Jinjin; Porter, Thomas R.

    2013-01-01

    Ultrasound induced cavitation has been explored as a method of dissolving intravascular and microvascular thrombi in acute myocardial infarction. The purpose of this study was to determine the type of cavitation required for success, and whether longer pulse duration therapeutic impulses (sustaining the duration of cavitation) could restore both microvascular and epicardial flow with this technique. Accordingly, in 36 hyperlipidemic atherosclerotic pigs, thrombotic occlusions were induced in the mid-left anterior descending artery. Pigs were then randomized to either a) ½ dose tissue plasminogen activator (0.5 mg/kg) alone; or same dose plasminogen activator and an intravenous microbubble infusion with either b) guided high mechanical index short pulse (2.0 MI; 5 usec) therapeutic ultrasound impulses; or c) guided 1.0 mechanical index long pulse (20 usec) impulses. Passive cavitation detectors indicated the high mechanical index impulses (both long and short pulse duration) induced inertial cavitation within the microvasculature. Epicardial recanalization rates following randomized treatments were highest in pigs treated with the long pulse duration therapeutic impulses (83% versus 59% for short pulse, and 49% for tissue plasminogen activator alone; p<0.05). Even without epicardial recanalization, however, early microvascular recovery occurred with both short and long pulse therapeutic impulses (p<0.005 compared to tissue plasminogen activator alone), and wall thickening improved within the risk area only in pigs treated with ultrasound and microbubbles. We conclude that although short pulse duration guided therapeutic impulses from a diagnostic transducer transiently improve microvascular flow, long pulse duration therapeutic impulses produce sustained epicardial and microvascular re-flow in acute myocardial infarction. PMID:23922797

  5. A novel procedure for detecting and focusing moving objects with SAR based on the Wigner-Ville distribution

    NASA Astrophysics Data System (ADS)

    Barbarossa, S.; Farina, A.

    A novel scheme for detecting moving targets with synthetic aperture radar (SAR) is presented. The proposed approach is based on the use of the Wigner-Ville distribution (WVD) for simultaneously detecting moving targets and estimating their motion kinematic parameters. The estimation plays a key role for focusing the target and correctly locating it with respect to the stationary background. The method has a number of advantages: (i) the detection is efficiently performed on the samples in the time-frequency domain, provided the WVD, without resorting to the use of a bank of filters, each one matched to possible values of the unknown target motion parameters; (ii) the estimation of the target motion parameters can be done on the same time-frequency domain by locating the line where the maximum energy of the WVD is concentrated. A validation of the approach is given by both analytical and simulation means. In addition, the estimation of the target kinematic parameters and the corresponding image focusing are also demonstrated.

  6. Ultrasound-induced DNA damage and signal transductions indicated by gammaH2AX

    NASA Astrophysics Data System (ADS)

    Furusawa, Yukihiro; Fujiwara, Yoshisada; Zhao, Qing-Li; Hassan, Mariame Ali; Ogawa, Ryohei; Tabuchi, Yoshiaki; Takasaki, Ichiro; Takahashi, Akihisa; Ohnishi, Takeo; Kondo, Takashi

    2011-09-01

    Ultrasound (US) has been shown to induce cancer cell death via different forms including apoptosis. Here, we report the potential of low-intensity pulsed US (LIPUS) to induce genomic DNA damage and subsequent DNA damage response. Using the ionizing radiation-induced DNA double-strand breaks (DSBs) as the positive control, we were able to observe the induction of DSBs (as neutral comet tails) and the subsequent formation of gammaH2AX-positive foci (by immunofluorescence detection) in human leukemia cells following exposure to LIPUS. The LIPUS-induced DNA damage arose most likely from the mechanical, but not sonochemical, effect of cavitation, based on our observation that the suppression of inertial cavitation abrogated the gammH2AX foci formation, whereas scavenging of free radical formation (e.g., hydroxyl radical) had no protective effect on it. Treatment with the specific kinase inhibitor of ATM or DNA-PKcs, which can phosphorylate H2AX Ser139, revealed that US-induced gammaH2AX was inhibited more effectively by the DNA-PK inhibitor than ATM kinase inhibitor. Notably, these inhibitor effects were opposite to those with radiation-induced gammH2AX. In conclusion, we report, for the first time that US can induce DNA damage and the DNA damage response as indicated by gammaH2AX was triggered by the cavitational mechanical effects. Thus, it is expected that the data shown here may provide a better understanding of the cellular responses to US.

  7. Ultrasound-induced thermal therapy of hyperplasia in ringed expanded polytetrafluoroethylene (eptfe) access grafts

    NASA Astrophysics Data System (ADS)

    Query, Michael Earl

    Hemodialysis vascular access, the interface between a dialysis patient and a dialysis machine, is quite literally the lifeblood of a patient's health. Vascular access dysfunction is the leading cause of hospitalization in hemodialysis patients. The occlusive growth of neointimal hyperplasia (NH) in expanded polytetrafluoroethylene (ePTFE) ringed grafts is the primary cause of failure. To further develop a proposed thermal ultrasound treatment to reduce or prevent NH in arteriovenous vascular grafts, the acoustic properties of ePTFE were studied in water and alcohol solutions. Previous reports of ePTFE acoustic properties are critiqued. It was found that the acoustic transmission and attenuation through ePTFE, and therefore the potential for an ultrasound-based therapy for NH, are heavily dependent on the medium in which the graft is immersed, suggesting that the acoustic properties of implanted grafts will change as grafts mature in vivo. The acoustic impedance and attenuation of water-soaked ePTFE were 0.478 +/- 1.43 x 10-2 MRayl and 1.78 +/- 0.111 Np/cm*MHz, respectively, while the acoustic impedance and attenuation of ePTFE in alcohol were 1.49 +/- 0.149 MRayl and 0.77 +/- 1.1 x 10-2 Np/cm*MHz, respectively. The use of focused ultrasound to heat implanted ringed ePTFE grafts was numerically modeled from 1.35- and 1.443-MHz transducers for in vitro geometries. Power deposition and heating, in turn, differed by an order of magnitude between various graft acoustic properties. Graft rings were predicted to be substantial absorbing and scattering features. In vitro phantom models were constructed: one with and one without thermocouples. At 1 W of acoustic power, the maximum temperature rise was 8˚ C. The thermocouple model containing a water-soaked graft did not experience heating in the far graft wall. The MRTI model confirmed that the graft rings are an absorbing/scattering feature. Heating was not prevented in the presence of water flow through the graft. Water

  8. Detection of measles, mumps and rubella viruses by immuno-colorimetric assay and its application in focus reduction neutralization tests.

    PubMed

    Vaidya, Sunil R; Kumbhar, Neelakshi S; Bhide, Vandana S

    2014-12-01

    Measles, mumps and rubella are vaccine-preventable diseases; however limited epidemiological data are available from low-income or developing countries. Thus, it is important to investigate the transmission of these viruses in different geographical regions. In this context, a cell culture-based rapid and reliable immuno-colorimetric assay (ICA) was established and its utility studied. Twenty-three measles, six mumps and six rubella virus isolates and three vaccine strains were studied. Detection by ICA was compared with plaque and RT-PCR assays. In addition, ICA was used to detect viruses in throat swabs (n = 24) collected from patients with suspected measles or mumps. Similarly, ICA was used in a focus reduction neutralization test (FRNT) and the results compared with those obtained by a commercial IgG enzyme immuno assay. Measles and mumps virus were detected 2 days post-infection in Vero or Vero-human signaling lymphocytic activation molecule cells, whereas rubella virus was detected 3 days post-infection in Vero cells. The blue stained viral foci were visible by the naked eye or through a magnifying glass. In conclusion, ICA was successfully used on 35 virus isolates, three vaccine strains and clinical specimens collected from suspected cases of measles and mumps. Furthermore, an application of ICA in a neutralization test (i.e., FRNT) was documented; this may be useful for sero-epidemiological, cross-neutralization and pre/post-vaccine studies.

  9. Detection of measles, mumps and rubella viruses by immuno-colorimetric assay and its application in focus reduction neutralization tests.

    PubMed

    Vaidya, Sunil R; Kumbhar, Neelakshi S; Bhide, Vandana S

    2014-12-01

    Measles, mumps and rubella are vaccine-preventable diseases; however limited epidemiological data are available from low-income or developing countries. Thus, it is important to investigate the transmission of these viruses in different geographical regions. In this context, a cell culture-based rapid and reliable immuno-colorimetric assay (ICA) was established and its utility studied. Twenty-three measles, six mumps and six rubella virus isolates and three vaccine strains were studied. Detection by ICA was compared with plaque and RT-PCR assays. In addition, ICA was used to detect viruses in throat swabs (n = 24) collected from patients with suspected measles or mumps. Similarly, ICA was used in a focus reduction neutralization test (FRNT) and the results compared with those obtained by a commercial IgG enzyme immuno assay. Measles and mumps virus were detected 2 days post-infection in Vero or Vero-human signaling lymphocytic activation molecule cells, whereas rubella virus was detected 3 days post-infection in Vero cells. The blue stained viral foci were visible by the naked eye or through a magnifying glass. In conclusion, ICA was successfully used on 35 virus isolates, three vaccine strains and clinical specimens collected from suspected cases of measles and mumps. Furthermore, an application of ICA in a neutralization test (i.e., FRNT) was documented; this may be useful for sero-epidemiological, cross-neutralization and pre/post-vaccine studies. PMID:25244651

  10. Mass spectrometry detection and imaging of inorganic and organic explosive device signatures using desorption electro-flow focusing ionization.

    PubMed

    Forbes, Thomas P; Sisco, Edward

    2014-08-01

    We demonstrate the coupling of desorption electro-flow focusing ionization (DEFFI) with in-source collision induced dissociation (CID) for the mass spectrometric (MS) detection and imaging of explosive device components, including both inorganic and organic explosives and energetic materials. We utilize in-source CID to enhance ion collisions with atmospheric gas, thereby reducing adducts and minimizing organic contaminants. Optimization of the MS signal response as a function of in-source CID potential demonstrated contrasting trends for the detection of inorganic and organic explosive device components. DEFFI-MS and in-source CID enabled isotopic and molecular speciation of inorganic components, providing further physicochemical information. The developed system facilitated the direct detection and chemical mapping of trace analytes collected with Nomex swabs and spatially resolved distributions within artificial fingerprints from forensic lift tape. The results presented here provide the forensic and security sectors a powerful tool for the detection, chemical imaging, and inorganic speciation of explosives device signatures. PMID:24968206

  11. Characterization of single α-tracks by photoresist detection and AFM analysis-focus on biomedical science and technology.

    PubMed

    Falzone, Nadia; Myhra, Sverre; Chakalova, Radka; Hill, Mark A; Thomson, James; Vallis, Katherine A

    2013-11-01

    The interactions between energetic ions and biological and/or organic target materials have recently attracted theoretical and experimental attention, due to their implications for detector and device technologies, and for therapeutic applications. Most of the attention has focused on detection of the primary ionization tracks, and their effects, while recoil target atom tracks remain largely unexplored. Detection of tracks by a negative tone photoresist (SU-8), followed by standard development, in combination with analysis by atomic force microscopy, shows that both primary and recoil tracks are revealed as conical spikes, and can be characterized at high spatial resolution. The methodology has the potential to provide detailed information about single impact events, which may lead to more effective and informative detector technologies and advanced therapeutic procedures. In comparison with current characterization methods the advantageous features include: greater spatial resolution by an order of magnitude (20 nm); detection of single primary and associated recoil tracks; increased range of fluence (to 2.5 × 10(9) cm(-2)); sensitivity to impacts at grazing angle incidence; and better definition of the lateral interaction volume in target materials.

  12. Characterization of single α-tracks by photoresist detection and AFM analysis-focus on biomedical science and technology.

    PubMed

    Falzone, Nadia; Myhra, Sverre; Chakalova, Radka; Hill, Mark A; Thomson, James; Vallis, Katherine A

    2013-11-01

    The interactions between energetic ions and biological and/or organic target materials have recently attracted theoretical and experimental attention, due to their implications for detector and device technologies, and for therapeutic applications. Most of the attention has focused on detection of the primary ionization tracks, and their effects, while recoil target atom tracks remain largely unexplored. Detection of tracks by a negative tone photoresist (SU-8), followed by standard development, in combination with analysis by atomic force microscopy, shows that both primary and recoil tracks are revealed as conical spikes, and can be characterized at high spatial resolution. The methodology has the potential to provide detailed information about single impact events, which may lead to more effective and informative detector technologies and advanced therapeutic procedures. In comparison with current characterization methods the advantageous features include: greater spatial resolution by an order of magnitude (20 nm); detection of single primary and associated recoil tracks; increased range of fluence (to 2.5 × 10(9) cm(-2)); sensitivity to impacts at grazing angle incidence; and better definition of the lateral interaction volume in target materials. PMID:24113400

  13. Nanocrystalline tin oxide nanofibers deposited by a novel focused electrospinning method. Application to the detection of TATP precursors.

    PubMed

    Santos, José Pedro; Fernández, Maria Jesús; Fontecha, José Luis; Matatagui, Daniel; Sayago, Isabel; Horrillo, Maria Carmen; Gracia, Isabel

    2014-01-01

    A new method of depositing tin dioxide nanofibers in order to develop chemical sensors is presented. It involves an electrospinning process with in-plane electrostatic focusing over micromechanized substrates. It is a fast and reproducible method. After an annealing process, which can be performed by the substrate heaters, it is observed that the fibers are intertwined forming porous networks that are randomly distributed on the substrate. The fiber diameters oscillate from 100 nm to 200 nm and fiber lengths reach several tens of microns. Each fiber has a polycrystalline structure with multiple nano-grains. The sensors have been tested for the detection of acetone and hydrogen peroxide (precursors of the explosive triacetone triperoxide, TATP) in air in the ppm range. High and fast responses to these gases have been obtained. PMID:25521384

  14. Nanocrystalline Tin Oxide Nanofibers Deposited by a Novel Focused Electrospinning Method. Application to the Detection of TATP Precursors

    PubMed Central

    Santos, José Pedro; Fernández, Maria Jesús; Fontecha, José Luis; Matatagui, Daniel; Sayago, Isabel; Horrillo, Maria Carmen; Gracia, Isabel

    2014-01-01

    A new method of depositing tin dioxide nanofibers in order to develop chemical sensors is presented. It involves an electrospinning process with in-plane electrostatic focusing over micromechanized substrates. It is a fast and reproducible method. After an annealing process, which can be performed by the substrate heaters, it is observed that the fibers are intertwined forming porous networks that are randomly distributed on the substrate. The fiber diameters oscillate from 100 nm to 200 nm and fiber lengths reach several tens of microns. Each fiber has a polycrystalline structure with multiple nano-grains. The sensors have been tested for the detection of acetone and hydrogen peroxide (precursors of the explosive triacetone triperoxide, TATP) in air in the ppm range. High and fast responses to these gases have been obtained. PMID:25521384

  15. Fast isoelectric focusing and antipeptide antibodies for detecting bovine casein in adulterated water buffalo milk and derived mozzarella cheese.

    PubMed

    Addeo, Francesco; Pizzano, Rosa; Nicolai, Maria Adalgisa; Caira, Simonetta; Chianese, Lina

    2009-11-11

    Plasmin hydrolysis of water buffalo casein (CN) can liberate a peptide comigrating with bovine gamma(2)-CN. Occurrence of this peptide may lead to false-positive detection of cow's milk for a genuine water buffalo cheese when it is analyzed by applying a fast version of the European official method for detecting bovine casein in water buffalo cheese. After isoelectric focusing of CN plasminolysates, performed according to the official method, immunoblot analysis with antipeptide antibodies was assayed to distinguish between gamma(2)-CN and the interfering bovine gamma(2)-CN-like peptide. Small, synthetic peptides containing partial sequences of bovine gamma(2)-CN were used as immunogens for antipeptide antibodies raised in rabbits. The antibody preparation directed toward the synthetic peptide containing the first five amino acid residues of gamma(2)-CN cross-reacted with native and in vitro generated gamma(2)-CN from bovine and water buffalo CN, but it did not recognize the bovine gamma(2)-CN-like band in the electrophoretic profile of pure water buffalo CN.

  16. In vitro characterization of perfluorocarbon droplets for focused ultrasound therapy

    NASA Astrophysics Data System (ADS)

    Schad, Kelly C.; Hynynen, Kullervo

    2010-09-01

    Focused ultrasound therapy can be enhanced with microbubbles by thermal and cavitation effects. However, localization of treatment is difficult as bioeffects can occur outside of the target region. Spatial control of bubbles can be achieved by ultrasound-induced conversion of liquid perfluorocarbon droplets to gas bubbles. This study was undertaken to determine the acoustic parameters for bubble production by droplet conversion and how it depends on the acoustic conditions and droplet physical parameters. Lipid-encapsulated droplets containing dodecafluoropentane were manufactured with sizes ranging from 1.9 to 7.2 µm in diameter and diluted to a concentration of 8 × 106 droplets mL-1. The droplets were sonicated in vitro with a focused ultrasound transducer and varying frequency and exposure under flow conditions through an acoustically transparent vessel. The sonications were 10 ms in duration at frequencies of 0.578, 1.736 and 2.855 MHz. The pressure threshold for droplet conversion was measured with an active transducer operating in pulse-echo mode and simultaneous measurements of broadband acoustic emissions were performed with passive acoustic detection. The results show that droplets cannot be converted at low frequency without broadband emissions occurring. However, the pressure threshold for droplet conversion decreased with increasing frequency, exposure and droplet size. The pressure threshold for broadband emissions was independent of the droplet size and was 2.9, 4.4 and 5.3 MPa for 0.578, 1736 and 2.855 MHz, respectively. In summary, we have demonstrated that droplet conversion is feasible for clinically relevant sized droplets and acoustic exposures.

  17. Rapid Focused Sequencing: A Multiplexed Assay for Simultaneous Detection and Strain Typing of Bacillus anthracis, Francisella tularensis, and Yersinia pestis

    PubMed Central

    Zolotova, Anna; Tan, Eugene; Selden, Richard F.

    2013-01-01

    Background The intentional release of Bacillus anthracis in the United States in 2001 has heightened concern about the use of pathogenic microorganisms in bioterrorism attacks. Many of the deadliest bacteria, including the Class A Select Agents Bacillus anthracis, Francisella tularensis, and Yersinia pestis, are highly infectious via the pulmonary route when released in aerosolized form. Hence, rapid, sensitive, and reliable methods for detection of these biothreats and characterization of their potential impact on the exposed population are of critical importance to initiate and support rapid military, public health, and clinical responses. Methodology/Principal Findings We have developed microfluidic multiplexed PCR and sequencing assays based on the simultaneous interrogation of three pathogens per assay and ten loci per pathogen. Microfluidic separation of amplified fluorescently labeled fragments generated characteristic electrophoretic signatures for identification of each agent. The three sets of primers allowed significant strain typing and discrimination from non-pathogenic closely-related species and environmental background strains based on amplicon sizes alone. Furthermore, sequencing of the 10 amplicons per pathogen, termed “Rapid Focused Sequencing,” allowed an even greater degree of strain discrimination and, in some cases, can be used to determine virulence. Both amplification and sequencing assays were performed in microfluidic biochips developed for fast thermal cycling and requiring 7 µL per reaction. The 30-plex sequencing assay resulted in genotypic resolution of 84 representative strains belonging to each of the three biothreat species. Conclusions/Significance The microfluidic multiplexed assays allowed identification and strain differentiation of the biothreat agents Bacillus anthracis, Francisella tularensis, and Yersinia pestis and clear discrimination from closely-related species and several environmental background strains. The

  18. Intrinsic Tryptophan Fluorescence in the Detection and Analysis of Proteins: A Focus on Förster Resonance Energy Transfer Techniques

    PubMed Central

    Ghisaidoobe, Amar B. T.; Chung, Sang J.

    2014-01-01

    Förster resonance energy transfer (FRET) occurs when the distance between a donor fluorophore and an acceptor is within 10 nm, and its application often necessitates fluorescent labeling of biological targets. However, covalent modification of biomolecules can inadvertently give rise to conformational and/or functional changes. This review describes the application of intrinsic protein fluorescence, predominantly derived from tryptophan (λEX ∼ 280 nm, λEM ∼ 350 nm), in protein-related research and mainly focuses on label-free FRET techniques. In terms of wavelength and intensity, tryptophan fluorescence is strongly influenced by its (or the protein’s) local environment, which, in addition to fluorescence quenching, has been applied to study protein conformational changes. Intrinsic Förster resonance energy transfer (iFRET), a recently developed technique, utilizes the intrinsic fluorescence of tryptophan in conjunction with target-specific fluorescent probes as FRET donors and acceptors, respectively, for real time detection of native proteins. PMID:25490136

  19. Ultrasound-Induced Organogel Formation Followed by Thin Film Fabrication via Simple Doctor Blading Technique for Field-Effect Transistor Applications.

    PubMed

    Xu, Jiaju; Wang, Yulong; Shan, Haiquan; Lin, Yiwei; Chen, Qian; Roy, V A L; Xu, Zongxiang

    2016-07-27

    We demonstrate doctor blading technique to fabricate high performance transistors made up of printed small molecular materials. In this regard, we synthesize a new soluble phthalocyanine, tetra-n-butyl peripheral substituted copper(II) phthalocaynine (CuBuPc), that can easily undergo gel formation upon ultrasonic irradiation, leading to the formation of three-dimensional (3D) network composed of one-dimensional (1D) nanofibers structure. Finally, taking the advantage of thixotropic nature of the CuBuPc organogel, we use the doctor blade processing technique that limits the material wastage for the fabrication of transistor devices. Due to the ultrasound induced stronger π-π interaction, the transistor fabricated by doctor blading based on CuBuPc organogel exhibits significant increase in charge carrier mobility in comparison with other solution process techniques, thus paving a way for a simple and economically viable preparation of electronic circuits.

  20. Ultrasound-Induced Organogel Formation Followed by Thin Film Fabrication via Simple Doctor Blading Technique for Field-Effect Transistor Applications.

    PubMed

    Xu, Jiaju; Wang, Yulong; Shan, Haiquan; Lin, Yiwei; Chen, Qian; Roy, V A L; Xu, Zongxiang

    2016-07-27

    We demonstrate doctor blading technique to fabricate high performance transistors made up of printed small molecular materials. In this regard, we synthesize a new soluble phthalocyanine, tetra-n-butyl peripheral substituted copper(II) phthalocaynine (CuBuPc), that can easily undergo gel formation upon ultrasonic irradiation, leading to the formation of three-dimensional (3D) network composed of one-dimensional (1D) nanofibers structure. Finally, taking the advantage of thixotropic nature of the CuBuPc organogel, we use the doctor blade processing technique that limits the material wastage for the fabrication of transistor devices. Due to the ultrasound induced stronger π-π interaction, the transistor fabricated by doctor blading based on CuBuPc organogel exhibits significant increase in charge carrier mobility in comparison with other solution process techniques, thus paving a way for a simple and economically viable preparation of electronic circuits. PMID:27377991

  1. Ultrasound-induced microbubble destruction promotes targeted delivery of adipose-derived stem cells to improve hind-limb ischemia of diabetic mice.

    PubMed

    Song, Ye; Xie, Xiaoyun; Gao, Yuan; Gu, Guojun; Wang, Peijun

    2016-01-01

    This study aimed to investigate whether ultrasound-induced microbubble destruction was able to promote targeted delivery of adipose-derived stem cells (ASCs) to improve hind-limb ischemia of diabetic mice. Ischemia was induced in the lower limb of db/db mice which were then randomly divided into 5 groups: PBS group, Sham group, ultrasound + microbubble group (US+MB), US+MB+ASCs group and ASCs group. Contrast-enhanced ultrasound perfusion imaging showed the ratio of blood flow in ischemic hind-limb to that in contralateral limb increased over time in five groups. A significant enhancement in US+MB+ASCs group was observed compared with US+MB group (P<0.01). Immunofluorescence microscopy of hind-limb muscle showed the microvessel density (microvessels/skeletal muscle fibers) and arteriolar density in US+MB+ASCs group were higher than in US+MB group, and significantly higher than in other control groups (P<0.01). Masson staining indicated the degree of muscle fibrosis in US+MB+ASCs group was lower than in US+MB. 3 and 7 days after therapy, ELISA and RT-PCR showed the expression of VEGF, P-selectin, ICAM-1 and SDF-1 in US+MB+ASCs group was higher than in US+MB group, and dramatically increased as compared to other groups (P<0.01). 3 and 7 days after therapy, Western blot assay showed the protein expression of P-P13K, P-AKT, VEGF, P-selectin, ICAM-1 and SDF-1 in US+MB+ASCs group was higher than US+MB group (P<0.01). The bioeffects of ultrasound-induced microbubble cavitation is able to up-regulate the expression of pro-inflammatory cytokines, which may improve the targeted delivery, adhesion and paracrine of ASCs, attenuating the hind-limb ischemia in diabetic mice. PMID:27398142

  2. Ultrasound-induced microbubble destruction promotes targeted delivery of adipose-derived stem cells to improve hind-limb ischemia of diabetic mice

    PubMed Central

    Song, Ye; Xie, Xiaoyun; Gao, Yuan; Gu, Guojun; Wang, Peijun

    2016-01-01

    This study aimed to investigate whether ultrasound-induced microbubble destruction was able to promote targeted delivery of adipose-derived stem cells (ASCs) to improve hind-limb ischemia of diabetic mice. Ischemia was induced in the lower limb of db/db mice which were then randomly divided into 5 groups: PBS group, Sham group, ultrasound + microbubble group (US+MB), US+MB+ASCs group and ASCs group. Contrast-enhanced ultrasound perfusion imaging showed the ratio of blood flow in ischemic hind-limb to that in contralateral limb increased over time in five groups. A significant enhancement in US+MB+ASCs group was observed compared with US+MB group (P<0.01). Immunofluorescence microscopy of hind-limb muscle showed the microvessel density (microvessels/skeletal muscle fibers) and arteriolar density in US+MB+ASCs group were higher than in US+MB group, and significantly higher than in other control groups (P<0.01). Masson staining indicated the degree of muscle fibrosis in US+MB+ASCs group was lower than in US+MB. 3 and 7 days after therapy, ELISA and RT-PCR showed the expression of VEGF, P-selectin, ICAM-1 and SDF-1 in US+MB+ASCs group was higher than in US+MB group, and dramatically increased as compared to other groups (P<0.01). 3 and 7 days after therapy, Western blot assay showed the protein expression of P-P13K, P-AKT, VEGF, P-selectin, ICAM-1 and SDF-1 in US+MB+ASCs group was higher than US+MB group (P<0.01). The bioeffects of ultrasound-induced microbubble cavitation is able to up-regulate the expression of pro-inflammatory cytokines, which may improve the targeted delivery, adhesion and paracrine of ASCs, attenuating the hind-limb ischemia in diabetic mice. PMID:27398142

  3. Acoustic cavitation-based monitoring of the reversibility and permeability of ultrasound-induced blood-brain barrier opening

    NASA Astrophysics Data System (ADS)

    Sun, Tao; Samiotaki, Gesthimani; Wang, Shutao; Acosta, Camilo; Chen, Cherry C.; Konofagou, Elisa E.

    2015-12-01

    Cavitation events seeded by microbubbles have been previously reported to be associated with MR- or fluorescent-contrast enhancement after focused ultrasound (FUS)-induced blood-brain barrier (BBB) opening. However, it is still unknown whether bubble activity can be correlated with the reversibility (the duration of opening and the likelihood of safe reinstatement) and the permeability of opened BBB, which is critical for the clinical translation of using passive cavitation detection to monitor, predict and control the opening. In this study, the dependence of acoustic cavitation on the BBB opening duration, permeability coefficient and histological damage occurrence were thus investigated. Transcranial pulsed FUS at 1.5 MHz in the presence of systemically circulating microbubbles was applied in the mouse hippocampi (n  =  60). The stable and inertial cavitation activities were monitored during sonication. Contrast-enhanced MRI was performed immediately after sonication and every 24 h up to 6 d thereafter, to assess BBB opening, brain tissue permeability and potential edema. Histological evaluations were used to assess the occurrence of neurovascular damages. It was found that stable cavitation was well correlated with: (1) the duration of the BBB opening (r2  =  0.77) (2) the permeability of the opened BBB (r2  =  0.82) (3) the likelihood of safe opening (P  <  0.05, safe opening compared to cases of damage; P  <  0.0001, no opening compared to safe opening). The inertial cavitation dose was correlated with the resulting BBB permeability (r2  =  0.72). Stable cavitation was found to be more reliable than inertial cavitation at assessing the BBB opening within the pressure range used in this study. This study demonstrates that the stable cavitation response during BBB opening holds promise for predicting and controlling the restoration and pharmacokinetics of FUS-opened BBB. The stable cavitation response therefore

  4. Acoustic cavitation-based monitoring of the reversibility and permeability of ultrasound-induced blood-brain barrier opening.

    PubMed

    Sun, Tao; Samiotaki, Gesthimani; Wang, Shutao; Acosta, Camilo; Chen, Cherry C; Konofagou, Elisa E

    2015-12-01

    Cavitation events seeded by microbubbles have been previously reported to be associated with MR- or fluorescent-contrast enhancement after focused ultrasound (FUS)-induced blood-brain barrier (BBB) opening. However, it is still unknown whether bubble activity can be correlated with the reversibility (the duration of opening and the likelihood of safe reinstatement) and the permeability of opened BBB, which is critical for the clinical translation of using passive cavitation detection to monitor, predict and control the opening. In this study, the dependence of acoustic cavitation on the BBB opening duration, permeability coefficient and histological damage occurrence were thus investigated. Transcranial pulsed FUS at 1.5 MHz in the presence of systemically circulating microbubbles was applied in the mouse hippocampi (n  =  60). The stable and inertial cavitation activities were monitored during sonication. Contrast-enhanced MRI was performed immediately after sonication and every 24 h up to 6 d thereafter, to assess BBB opening, brain tissue permeability and potential edema. Histological evaluations were used to assess the occurrence of neurovascular damages. It was found that stable cavitation was well correlated with: (1) the duration of the BBB opening (r(2)  =  0.77); (2) the permeability of the opened BBB (r(2)  =  0.82); (3) the likelihood of safe opening (P  <  0.05, safe opening compared to cases of damage; P  <  0.0001, no opening compared to safe opening). The inertial cavitation dose was correlated with the resulting BBB permeability (r(2)  =  0.72). Stable cavitation was found to be more reliable than inertial cavitation at assessing the BBB opening within the pressure range used in this study. This study demonstrates that the stable cavitation response during BBB opening holds promise for predicting and controlling the restoration and pharmacokinetics of FUS-opened BBB. The stable cavitation response

  5. Detection of Nitro-Based and Peroxide-Based Explosives by Fast Polarity-Switchable Ion Mobility Spectrometer with Ion Focusing in Vicinity of Faraday Detector

    PubMed Central

    Zhou, Qinghua; Peng, Liying; Jiang, Dandan; Wang, Xin; Wang, Haiyan; Li, Haiyang

    2015-01-01

    Ion mobility spectrometer (IMS) has been widely deployed for on-site detection of explosives. The common nitro-based explosives are usually detected by negative IMS while the emerging peroxide-based explosives are better detected by positive IMS. In this study, a fast polarity-switchable IMS was constructed to detect these two explosive species in a single measurement. As the large traditional Faraday detector would cause a trailing reactant ion peak (RIP), a Faraday detector with ion focusing in vicinity was developed by reducing the detector radius to 3.3 mm and increasing the voltage difference between aperture grid and its front guard ring to 591 V, which could remove trailing peaks from RIP without loss of signal intensity. This fast polarity-switchable IMS with ion focusing in vicinity of Faraday detector was employed to detect a mixture of 10 ng 2,4,6-trinitrotoluene (TNT) and 50 ng hexamethylene triperoxide diamine (HMTD) by polarity-switching, and the result suggested that [TNT-H]− and [HMTD+H]+ could be detected in a single measurement. Furthermore, the removal of trailing peaks from RIP by the Faraday detector with ion focusing in vicinity also promised the accurate identification of KClO4, KNO3 and S in common inorganic explosives, whose product ion peaks were fairly adjacent to RIP. PMID:26021282

  6. Windows of detection of lorazepam in urine, oral fluid and hair, with a special focus on drug-facilitated crimes.

    PubMed

    Kintz, Pascal; Villain, Marion; Cirimele, Vincent; Pépin, Gilbert; Ludes, Bertrand

    2004-10-29

    The purported lowering of sex opposition, coupled with a possible abrupt unconsciousness-inducing effect and ease of administration in spiked drinks have resulted in the use of hypnotics in cases of drug-facilitated offense. Among these compounds, lorazepam possesses amnesic properties and can impair an individual rapidly. The chances to detect this substance increase if the most sensitive methods are used and if the biological fluid which allows the longest possible detection time is available. In order to document the window of detection of lorazepam, we have orally administered 2.5 mg of the drug to three volunteers and collected oral fluid (n = l) over 8 h, urine (n = 2) over 144 h and hair (n = 3) 4 weeks after exposure. Lorazepam was analyzed by LC-MS/MS after alkalinisation (to pH 8.4 with phosphate buffer) and extraction by dichloromethane/diethyl ether in presence of diazepam-d5, used as internal standard. Reversed-phase separation on a XTerra C18 column was achieved in 12 min, under gradient conditions. Molecular ions (m/z 321 and 290 for lorazepam and the IS, respectively) were selected in Ql and the corresponding daughter ions (m/z 303 and 275 for lorazepam and m/z 154 and 198 for the IS) were detected in Q3 after collision with argon. Urine tested positive for lorazepam over 144 h (2-4 ng/ml), with a peak detected after 24 h exposure (411-880 ng/ml). Oral fluid tested positive for lorazepam over 8 h (0.7 ng/ml). Despite a limit of quantitation at 1 pg/mg, we were unable to detect a single lorazepam dose in hair, contrarily to most other benzodiazepines that are detectable. Therefore, in case of drug-facilitated crimes involving lorazepam, urine appears as the best specimen to document exposure, particularly if LC-MS/MS is used.

  7. High-precision topography measurement through accurate in-focus plane detection with hybrid digital holographic microscope and white light interferometer module.

    PubMed

    Liżewski, Kamil; Tomczewski, Sławomir; Kozacki, Tomasz; Kostencka, Julianna

    2014-04-10

    High-precision topography measurement of micro-objects using interferometric and holographic techniques can be realized provided that the in-focus plane of an imaging system is very accurately determined. Therefore, in this paper we propose an accurate technique for in-focus plane determination, which is based on coherent and incoherent light. The proposed method consists of two major steps. First, a calibration of the imaging system with an amplitude object is performed with a common autofocusing method using coherent illumination, which allows for accurate localization of the in-focus plane position. In the second step, the position of the detected in-focus plane with respect to the imaging system is measured with white light interferometry. The obtained distance is used to accurately adjust a sample with the precision required for the measurement. The experimental validation of the proposed method is given for measurement of high-numerical-aperture microlenses with subwavelength accuracy.

  8. Saving cells from ultrasound-induced apoptosis: quantification of cell death and uptake following sonication and effects of targeted calcium chelation

    PubMed Central

    Hutcheson, J.D.; Schlicher, R.K.; Hicks, H.K.; Prausnitz, M.R.

    2010-01-01

    Applications of ultrasound for non-invasive drug and gene delivery have been limited by associated cell death due to sonication. In this study, we sought to quantify the distribution of cellular bioeffects caused by low-frequency ultrasound (24 kHz) and test the hypothesis that Ca2+ chelation after sonication can shift this distribution by saving cells from death by apoptosis. Using flow cytometry, we quantitatively categorized sonicated cells among four populations: (1) cells that appear largely unaffected, (2) cells reversibly permeabilized, (3) cells rendered nonviable during sonication and (4) cells that appear to be viable shortly after sonication, but later undergo apoptosis and die. By monitoring cells for 6 h after ultrasound exposure, we found that up to 15% of intact cells fell into this final category. Those apoptotic cells initially had the highest levels of uptake of a marker compound, calcein; also had highly elevated levels of intracellular Ca2+; and contained an estimated plasma membrane wound radius of 100 – 300 nm. Finally, we showed that chelation of intracellular Ca2+ after sonication reduced apoptosis by up to 44%, thereby providing a strategy to save cells. We conclude that cells can be saved from ultrasound-induced death by appropriate selection of ultrasound conditions and Ca2+ chelation after sonication. PMID:20447754

  9. Exploring recruitment barriers and facilitators in early cancer detection trials: the use of pre-trial focus groups

    PubMed Central

    2014-01-01

    Background Recruiting to randomized controlled trials is fraught with challenges; with less than one third recruiting to their original target. In preparation for a trial evaluating the effectiveness of a blood test to screen for lung cancer (the ECLS trial), we conducted a qualitative study to explore the potential barriers and facilitators that would impact recruitment. Methods Thirty two people recruited from community settings took part in four focus groups in Glasgow and Dundee (UK). Thematic analysis was used to code the data and develop themes. Results Three sub-themes were developed under the larger theme of recruitment strategies. The first of these themes, recruitment options, considered that participants largely felt that the invitation to participate letter should come from GPs, with postal reminders and face-to-face reminders during primary care contacts. The second theme dealt with understanding randomization and issues related to the control group (where bloods were taken but not tested). Some participants struggled with the concept or need for randomization, or for the need for a control group. Some reported that they would not consider taking part if allocated to the control group, but others were motivated to take part even if allocated to the control group by altruism. The final theme considered perceived barriers to participation and included practical barriers (such as flexible appointments and reimbursement of travel expenses) and psychosocial barriers (such as feeling stigmatized because of their smoking status and worries about being coerced into stopping smoking). Conclusions Focus groups provided useful information which resulted in numerous changes to proposed trial documentation and processes. This was in order to address participants information needs, improve comprehension of the trial documentation, enhance facilitators and remove barriers to participation. The modifications made in light of these findings may enhance trial

  10. Side-by-side comparison of disposable microchips with commercial capillary cartridges for application in capillary isoelectric focusing with whole column imaging detection.

    PubMed

    Liu, Zhen; Ou, Junjie; Samy, Razim; Glawdel, Tomasz; Huang, Tiemin; Ren, Carolyn L; Pawliszyn, Janusz

    2008-10-01

    Simple-structured, well-functioned disposable poly(dimethylsiloxane) (PDMS) microchips were developed for capillary isoelectric focusing with whole column imaging detection (CIEF-WCID). Side-by-side comparison of the developed microchips with well-established commercial capillary cartridges demonstrated that the disposable microchips have comparable performance as well as advantages such as absence of lens effect and possibility of high-aspect-ratio accompanied with a dramatic reduction in cost.

  11. A new multichannel time reversal focusing method for circumferential Lamb waves and its applications for defect detection in thick-walled pipe with large-diameter.

    PubMed

    Liu, Zenghua; Xu, Qinglong; Gong, Yu; He, Cunfu; Wu, Bin

    2014-09-01

    This paper proposes a new multichannel time reversal focusing (MTRF) method for circumferential Lamb waves which is based on modified time reversal algorithm and applies this method for detecting different kinds of defects in thick-walled pipe with large-diameter. The principle of time reversal of circumferential Lamb waves in pipe is presented along with the influence from multiple guided wave modes and propagation paths. Experimental study is carried out in a thick-walled and large-diameter pipe with three artificial defects, namely two axial notches on its inner and outer surface respectively, and a corrosion-like defect on its outer surface. By using the proposed MTRF method, the multichannel signals focus at the defects, leading to the amplitude improvement of the defect scattered signal. Besides, another energy focus arises in the direct signal due to the partial compensation of dispersion and multimode of circumferential Lamb waves, alongside the multichannel focusing, during MTRF process. By taking the direct focus as a time base, accurate defect localization is implemented. Secondly, a new phenomenon is exhibited in this paper that defect scattered wave packet appears just before the right boundary of truncation window after time reversal, and to which two feasible explanations are given. Moreover, this phenomenon can be used as the theoretical basis in the determination of defect scattered waves in time reversal response signal. At last, in order to detect defects without prior knowing their exact position, a large-range truncation window is used in the proposed method. As a result, the experimental operation of MTRF method is simplified and defect detection and localization are well accomplished. PMID:24877582

  12. Serum Lipidomics Profiling using LC-MS and High Energy Collisional Dissociation Fragmentation: Focus on Triglyceride Detection and Characterization

    PubMed Central

    Bird, Susan S.; Marur, Vasant R.; Sniatynski, Matthew J.; Greenberg, Heather K.; Kristal, Bruce S.

    2011-01-01

    There is a growing need both clinically and experimentally to improve the characterization of blood lipids. A liquid chromatography-mass spectrometry (LC-MS) method, developed for the qualitative and semi-quantitative detection of lipids in biological samples and previously validated in mitochondrial samples, was now evaluated for the profiling of serum lipids. Data were acquired using high resolution full scan MS and high energy collisional dissociation (HCD) all ion fragmentation. The method was designed for efficient separation and detection in both positive and negative ionization mode and evaluated using standards spanning 7 lipid classes. Platform performance, related to the identification and characterization of serum triglycerides (TGs) was assessed using extracted ion chromatograms with mass tolerance windows of 5 ppm or less from full scan exact mass measurements determined using SIEVE non-differential LC-MS analysis software. The platform showed retention time coefficients of variation (CV) < 0.3%, mass accuracy values < 2 ppm error and peak area CV < 13%, with the majority of that error coming from sample preparation and extraction rather than the LC-MS analysis and linearity was shown to be over four orders of magnitude (r2=0.999) for the standard TG (15:0)3 spiked into serum. Instrument mass accuracy and precision were critical to the identification of unknown TG species, in part because these parameters enabled us to reduce false positives. In addition to detection and relative quantitation of TGs in serum, TG structures were characterized through the use of alternating HCD scans at different energies to produce diagnostic fragmentations on all ions in the analysis. The lipidomics method was applied to serum samples from 192 rats maintained on diets differing in macronutrient composition. The analysis identified 86 TG species with 81 unique masses that varied over 3.5 orders of magnitude and showed diet-dependency - consistent with TGs linking diet

  13. Harmonic motion imaging for abdominal tumor detection and high-intensity focused ultrasound ablation monitoring: an in vivo feasibility study in a transgenic mouse model of pancreatic cancer.

    PubMed

    Chen, Hong; Hou, Gary Y; Han, Yang; Payen, Thomas; Palermo, Carmine F; Olive, Kenneth P; Konofagou, Elisa E

    2015-09-01

    Harmonic motion imaging (HMI) is a radiationforce- based elasticity imaging technique that tracks oscillatory tissue displacements induced by sinusoidal ultrasonic radiation force to assess the resulting oscillatory displacement denoting the underlying tissue stiffness. The objective of this study was to evaluate the feasibility of HMI in pancreatic tumor detection and high-intensity focused ultrasound (HIFU) treatment monitoring. The HMI system consisted of a focused ultrasound transducer, which generated sinusoidal radiation force to induce oscillatory tissue motion at 50 Hz, and a diagnostic ultrasound transducer, which detected the axial tissue displacements based on acquired radio-frequency signals using a 1-D cross-correlation algorithm. For pancreatic tumor detection, HMI images were generated for pancreatic tumors in transgenic mice and normal pancreases in wild-type mice. The obtained HMI images showed a high contrast between normal and malignant pancreases with an average peak-to-peak HMI displacement ratio of 3.2. Histological analysis showed that no tissue damage was associated with HMI when it was used for the sole purpose of elasticity imaging. For pancreatic tumor ablation monitoring, the focused ultrasound transducer was operated at a higher acoustic power and longer pulse length than that used in tumor detection to simultaneously induce HIFU thermal ablation and oscillatory tissue displacements, allowing HMI monitoring without interrupting tumor ablation. HMI monitoring of HIFU ablation found significant decreases in the peak-to-peak HMI displacements before and after HIFU ablation with a reduction rate ranging from 15.8% to 57.0%. The formation of thermal lesions after HIFU exposure was confirmed by histological analysis. This study demonstrated the feasibility of HMI in abdominal tumor detection and HIFU ablation monitoring.

  14. Harmonic Motion Imaging for Abdominal Tumor Detection and High-intensity Focused Ultrasound Ablation Monitoring: A Feasibility Study in a Transgenic Mouse Model of Pancreatic Cancer

    PubMed Central

    Chen, Hong; Hou, Gary Y.; Han, Yang; Payen, Thomas; Palermo, Carmine F.; Olive, Kenneth P.; Konofagou, Elisa E.

    2015-01-01

    Harmonic motion imaging (HMI) is a radiation force-based elasticity imaging technique that tracks oscillatory tissue displacements induced by sinusoidal ultrasonic radiation force to assess relative tissue stiffness. The objective of this study was to evaluate the feasibility of HMI in pancreatic tumor detection and high-intensity focused ultrasound (HIFU) treatment monitoring. The HMI system consisted of a focused ultrasound transducer, which generated sinusoidal radiation force to induce oscillatory tissue motion at 50 Hz, and a diagnostic ultrasound transducer, which detected the axial tissue displacements based on acquired radiofrequency signals using a 1D cross-correlation algorithm. For pancreatic tumor detection, HMI images were generated for pancreatic tumors in transgenic mice and normal pancreases in wild-type mice. The obtained HMI images showed a high contrast between normal and malignant pancreases with an average peak-to-peak HMI displacement ratio of 3.2. Histological analysis showed that no tissue damage was associated with HMI when it was used for the sole purpose of elasticity imaging. For pancreatic tumor ablation monitoring, the focused ultrasound transducer was operated with a higher acoustic power and longer pulse length than that used in tumor detection to simultaneously induce HIFU thermal ablation and oscillatory tissue displacements, allowing HMI monitoring without interrupting tumor ablation. HMI monitoring of HIFU ablation found significant decreases in the peak-to-peak HMI displacements before and after HIFU ablation with a reduction rate ranging from 15.8% to 57.0%. The formation of thermal lesions after HIFU exposure was confirmed by histological analysis. This study demonstrated the feasibility of HMI in abdominal tumor detection and HIFU ablation monitoring. PMID:26415128

  15. A microfluidic device for label-free detection of Escherichia coli in drinking water using positive dielectrophoretic focusing, capturing, and impedance measurement.

    PubMed

    Kim, Myounggon; Jung, Taekeon; Kim, Youngjin; Lee, Changgeun; Woo, Kyungchul; Seol, Jae Hun; Yang, Sung

    2015-12-15

    While sensors that allow for high-throughput enumeration of microorganisms within drinking water are useful for water quality monitoring, it is particularly challenging to accurately quantify microorganisms that are present in low numbers (<100 CFU/mL) in a high-throughput manner. Negative dielectrophoresis (nDEP) is typically utilized in DEP-based cell focusing methods; however, due to its low conductivity, drinking water cannot be analyzed by this approach. Here, we report a positive DEP (pDEP)-based Escherichia coli detection system that is integrated with a focusing and sensing electrode. By incorporating a passivation layer, we avoided issues with adhesion of E. coli to the electrode, and achieved efficient cell focusing under high flow rate conditions (1500 μL/h). The resulting focused E. coli cells were then trapped on the sensor electrode, resulting in changes in impedance. The proposed system was evaluated using four different E. coli populations (150-1500 CFU/mL). We successfully enumerated populations as low as 300 CFU/mL within 1 min, and the signal variation was 1.13±0.37%. The device introduced in this study provides the basis for the development of portable, highly sensitive microorganism sensors that enable rapid detection of bacteria in drinking water.

  16. Plaque/focus immunoassay: a simple method for detecting antiviral monoclonal or other antibodies and viral antigens in cells.

    PubMed

    Pauli, G; Gregersen, J P; Ludwig, H

    1984-11-30

    A new, simple enzyme-linked immunosorbent assay (ELISA) is described which is performed directly on infected and fixed cell cultures in microtitre plates. It permits large scale screening of antiviral monoclonal antibodies and differentiation of specific antibodies from those usually responsible for high background reactions in other ELISA techniques. Time consuming purification of antigens is thus avoided. The plaque/focus immunoassay is also applicable to titration of antibodies in patients' sera and antigens in lytically or non-lytically virus-infected cells. It may also be used to localize antigens in different cell compartments. This immunoassay requires no special equipment and results may be evaluated either with the naked eye or using a light microscope.

  17. Analysis of global Terrestrial Gamma Ray Flashes distribution and special focus on AGILE detections over South America

    NASA Astrophysics Data System (ADS)

    Fabró, Ferran; Montanyà, Joan; Marisaldi, Martino; van der Velde, Oscar A.; Fuschino, Fabio

    2015-03-01

    Global distribution of the Terrestrial Gamma-ray Flashes (TGFs) detected by AGILE and RHESSI for the period from March 2009 to July 2012 has been analysed. A fourth TGF production region has been distinguished over the Pacific. It is confirmed that TGF occurrence follows the Intertropical Convergence Zone (ITCZ) seasonal migration and prefers afternoons. TGF/lightning ratio appears to be lower over America than other regions suggesting that meteorological regional differences are important for the TGF production. Diurnal cycle of TGFs peaks in the afternoon suggesting that Convective Available Potential Energy (CAPE) and convection are important for TGF production. Moreover all AGILE passages over South America in the same period have been analysed to find meteorological preferences for TGF occurrence. In each passage the analysis of Cloud Top Altitude (CTA), CAPE, number of strokes, number of storms and coverage area of clouds with temperatures below -70 °C (Cloud Top Coverage area, CTC) are computed. On average, AGILE has been exposed to 19,100 strokes between each TGF representing ∼68 h of exposure over active storms. High CAPE values, high cloud tops and high stroke occurrence suggest that meteorological conditions conducive to vigorous and electrically active storms are important for TGF production. It is shown that a high number of thunderstorms is preferable for TGF production which may be explained by a greater chance of the presence of a thunderstorm in the best development stage for TGF production. High tropopause altitude seems to be important but not primordial for TGF production.

  18. Comparative study on the effectiveness of different mosquito traps in arbovirus surveillance with a focus on WNV detection.

    PubMed

    Pezzin, Alex; Sy, Victoria; Puggioli, Arianna; Veronesi, Rodolfo; Carrieri, Marco; Maccagnani, Bettina; Bellini, Romeo

    2016-01-01

    The selection of the ideal trap for arbovirus surveillance is an issue of primary importance to increase the sensitivity of virus detection and the cost-effectiveness of the entomological surveillance. During the summer 2011, the effectiveness of five types of mosquito traps (CDC gravid trap, CO2(-)baited trap, BG-Sentinel™ and two experimental prototypes) to attract females potentially infected with West Nile virus were assessed. The study was carried out in three natural wetland sites located in the Emilia-Romagna Region (Northern Italy), using a Latin square scheme. Single night collections of adult females were performed and determination of species and physiological state (gravid, nulliparous or parous) was made upon return to the laboratory. The species most frequently collected in the gravid trap was Culex pipiens sl. L., being gravid females the large majority of the individuals. Species diversity was much higher in CO2(-)baited traps, which may therefore enable a more comprehensive description of the vector species composition and their role in arboviruses circulation. Our findings indicate that gravid traps can be a valid tool and should be integrated in the West Nile virus surveillance system in the Emilia-Romagna region, mainly based on collections made with CO2-baited traps.

  19. Comparative study on the effectiveness of different mosquito traps in arbovirus surveillance with a focus on WNV detection.

    PubMed

    Pezzin, Alex; Sy, Victoria; Puggioli, Arianna; Veronesi, Rodolfo; Carrieri, Marco; Maccagnani, Bettina; Bellini, Romeo

    2016-01-01

    The selection of the ideal trap for arbovirus surveillance is an issue of primary importance to increase the sensitivity of virus detection and the cost-effectiveness of the entomological surveillance. During the summer 2011, the effectiveness of five types of mosquito traps (CDC gravid trap, CO2(-)baited trap, BG-Sentinel™ and two experimental prototypes) to attract females potentially infected with West Nile virus were assessed. The study was carried out in three natural wetland sites located in the Emilia-Romagna Region (Northern Italy), using a Latin square scheme. Single night collections of adult females were performed and determination of species and physiological state (gravid, nulliparous or parous) was made upon return to the laboratory. The species most frequently collected in the gravid trap was Culex pipiens sl. L., being gravid females the large majority of the individuals. Species diversity was much higher in CO2(-)baited traps, which may therefore enable a more comprehensive description of the vector species composition and their role in arboviruses circulation. Our findings indicate that gravid traps can be a valid tool and should be integrated in the West Nile virus surveillance system in the Emilia-Romagna region, mainly based on collections made with CO2-baited traps. PMID:26466982

  20. Focus on the "unstable" carotid plaque: detection of intraplaque angiogenesis with contrast ultrasound. Present state and future perspectives.

    PubMed

    Giannoni, Maria Fabrizia; Vicenzini, Edoardo

    2009-04-01

    Over the past 20 years, conventional ultrasonography has identified features of the "unstable" carotid plaque. Histological studies have recognized that plaque inflammation and neoangiogenesis play a pivotal role in the developing of the vulnerable plaque. Hence, the growing interest on the biological activities of atherosclerotic lesions leading to cerebrovascular events. The presence of adventitial vasa vasorum and the occurrence of plaque vascularization have been considered as predictors of unstable lesions in cerebrovascular and/or cardiovascular patients. The advent of ultrasound contrast agents has represented a fundamental step in the up-to-date functional evaluation in several fields with minimally invasive procedures. Contrast specific ultrasound modalities are currently used with excellent results in oncology, in cardiology and in vascular diseases. Contrast carotid ultrasound is an emerging imaging technique, able to depict in vivo new functional information on plaque activity and vascularization that may add further new data on the actual condition and future cerebrovascular risk. Further studies will provide a better clarification of the degree of neo-angiogenesis. A future strategy could be represented by the monitoring of plaque neoangiogenesis in order to detect the possible pharmacological effects on plaque remodeling.

  1. Pharmacokinetics of BPA in Gliomas with Ultrasound Induced Blood-Brain Barrier Disruption as Measured by Microdialysis

    PubMed Central

    Yang, Feng-Yi; Lin, Yi-Li; Chou, Fong-In; Lin, Yu-Chuan; Hsueh Liu, Yen-Wan; Chang, Lun-Wei; Hsieh, Yu-Ling

    2014-01-01

    The blood-brain barrier (BBB) can be transiently disrupted by focused ultrasound (FUS) in the presence of microbubbles for targeted drug delivery. Previous studies have illustrated the pharmacokinetics of drug delivery across the BBB after sonication using indirect visualization techniques. In this study, we investigated the in vivo extracellular kinetics of boronophenylalanine-fructose (BPA-f) in glioma-bearing rats with FUS-induced BBB disruption by microdialysis. After simultaneous intravenous administration of BPA and FUS exposure, the boron concentration in the treated brains was quantified by inductively coupled plasma mass spectroscopy. With FUS, the mean peak concentration of BPA-f in the glioma dialysate was 3.6 times greater than without FUS, and the area under the concentration-time curve was 2.1 times greater. This study demonstrates that intracerebral microdialysis can be used to assess local BBB transport profiles of drugs in a sonicated site. Applying microdialysis to the study of metabolism and pharmacokinetics is useful for obtaining selective information within a specific brain site after FUS-induced BBB disruption. PMID:24936788

  2. Magnetic resonance thermometry at 7T for real-time monitoring and correction of ultrasound induced mild hyperthermia.

    PubMed

    Fite, Brett Z; Liu, Yu; Kruse, Dustin E; Caskey, Charles F; Walton, Jeffrey H; Lai, Chun-Yen; Mahakian, Lisa M; Larrat, Benoit; Dumont, Erik; Ferrara, Katherine W

    2012-01-01

    While Magnetic Resonance Thermometry (MRT) has been extensively utilized for non-invasive temperature measurement, there is limited data on the use of high field (≥7T) scanners for this purpose. MR-guided Focused Ultrasound (MRgFUS) is a promising non-invasive method for localized hyperthermia and drug delivery. MRT based on the temperature sensitivity of the proton resonance frequency (PRF) has been implemented in both a tissue phantom and in vivo in a mouse Met-1 tumor model, using partial parallel imaging (PPI) to speed acquisition. An MRgFUS system capable of delivering a controlled 3D acoustic dose during real time MRT with proportional, integral, and derivative (PID) feedback control was developed and validated. Real-time MRT was validated in a tofu phantom with fluoroptic temperature measurements, and acoustic heating simulations were in good agreement with MR temperature maps. In an in vivo Met-1 mouse tumor, the real-time PID feedback control is capable of maintaining the desired temperature with high accuracy. We found that real time MR control of hyperthermia is feasible at high field, and k-space based PPI techniques may be implemented for increasing temporal resolution while maintaining temperature accuracy on the order of 1°C.

  3. Magnetic Resonance Thermometry at 7T for Real-Time Monitoring and Correction of Ultrasound Induced Mild Hyperthermia

    PubMed Central

    Fite, Brett Z.; Liu, Yu; Kruse, Dustin E.; Caskey, Charles F.; Walton, Jeffrey H.; Lai, Chun-Yen; Mahakian, Lisa M.; Larrat, Benoit; Dumont, Erik; Ferrara, Katherine W.

    2012-01-01

    While Magnetic Resonance Thermometry (MRT) has been extensively utilized for non-invasive temperature measurement, there is limited data on the use of high field (≥7T) scanners for this purpose. MR-guided Focused Ultrasound (MRgFUS) is a promising non-invasive method for localized hyperthermia and drug delivery. MRT based on the temperature sensitivity of the proton resonance frequency (PRF) has been implemented in both a tissue phantom and in vivo in a mouse Met-1 tumor model, using partial parallel imaging (PPI) to speed acquisition. An MRgFUS system capable of delivering a controlled 3D acoustic dose during real time MRT with proportional, integral, and derivative (PID) feedback control was developed and validated. Real-time MRT was validated in a tofu phantom with fluoroptic temperature measurements, and acoustic heating simulations were in good agreement with MR temperature maps. In an in vivo Met-1 mouse tumor, the real-time PID feedback control is capable of maintaining the desired temperature with high accuracy. We found that real time MR control of hyperthermia is feasible at high field, and k-space based PPI techniques may be implemented for increasing temporal resolution while maintaining temperature accuracy on the order of 1°C. PMID:22536396

  4. Qualitative and Quantitative Analysis of Molecular Delivery Through the Ultrasound-Induced Blood-Brain Barrier Opening in Mice

    NASA Astrophysics Data System (ADS)

    Wang, Shougang; Baseri, Babak; Choi, James J.; Tung, Yao-Sheng; Morrison, Barclay; Konofagou, Elisa E.

    2009-04-01

    Recent studies have proven that focused ultrasound (FUS) in the presence of microbubbles can deliver large molecules across the blood-brain barrier (BBB) locally, transiently and non-invasively. In this study, the cellular effects, the size estimation of the opening and the amount delivered were inferred through qualitative and quantitative analysis of molecular delivery to the brain parenchyma in a murine model. The ultimate purpose was to build the foundation for future ultrasound-facilitated neurodegenerative disease treatment in humans. A bolus of microbubbles at 1 μl/g body weight concentration was intravenously injected. Pulsed FUS was applied to the left hippocampus through the intact skin and skull followed by intravenously administration of fluorescence-conjugated dextran at 3 kDa, 10 kDa and 70 kDa. The brain were either sectioned for fluorescence imaging or homogenized for quantitative analysis. The concentration of 3 kDa, 10 kDa and 70 kDa dextrans delivered to the left brain hemisphere was quantified to be 7.9±4.9 μg/g, 2.4±1.3 μg/g and 0.9±0.47 μg/g of brain weight. Smooth muscle cells engulfing the arterioles exhibited higher fluorescence in the case of 70 kDa dextran, compared to the 3 kDa dextran, demonstrating that fluorescence imaging can help with the understanding of the type of mechanism of molecular uptake by different brain cells.

  5. New pediatric vision screener employing polarization-modulated, retinal-birefringence-scanning-based strabismus detection and bull's eye focus detection with an improved target system: opto-mechanical design and operation

    NASA Astrophysics Data System (ADS)

    Irsch, Kristina; Gramatikov, Boris I.; Wu, Yi-Kai; Guyton, David L.

    2014-06-01

    Amblyopia ("lazy eye") is a major public health problem, caused by misalignment of the eyes (strabismus) or defocus. If detected early in childhood, there is an excellent response to therapy, yet most children are detected too late to be treated effectively. Commercially available vision screening devices that test for amblyopia's primary causes can detect strabismus only indirectly and inaccurately via assessment of the positions of external light reflections from the cornea, but they cannot detect the anatomical feature of the eyes where fixation actually occurs (the fovea). Our laboratory has been developing technology to detect true foveal fixation, by exploiting the birefringence of the uniquely arranged Henle fibers delineating the fovea using retinal birefringence scanning (RBS), and we recently described a polarization-modulated approach to RBS that enables entirely direct and reliable detection of true foveal fixation, with greatly enhanced signal-to-noise ratio and essentially independent of corneal birefringence (a confounding variable with all polarization-sensitive ophthalmic technology). Here, we describe the design and operation of a new pediatric vision screener that employs polarization-modulated, RBS-based strabismus detection and bull's eye focus detection with an improved target system, and demonstrate the feasibility of this new approach.

  6. New pediatric vision screener employing polarization-modulated, retinal-birefringence-scanning-based strabismus detection and bull's eye focus detection with an improved target system: opto-mechanical design and operation.

    PubMed

    Irsch, Kristina; Gramatikov, Boris I; Wu, Yi-Kai; Guyton, David L

    2014-06-01

    Amblyopia ("lazy eye") is a major public health problem, caused by misalignment of the eyes (strabismus) or defocus. If detected early in childhood, there is an excellent response to therapy, yet most children are detected too late to be treated effectively. Commercially available vision screening devices that test for amblyopia's primary causes can detect strabismus only indirectly and inaccurately via assessment of the positions of external light reflections from the cornea, but they cannot detect the anatomical feature of the eyes where fixation actually occurs (the fovea). Our laboratory has been developing technology to detect true foveal fixation, by exploiting the birefringence of the uniquely arranged Henle fibers delineating the fovea using retinal birefringence scanning (RBS), and we recently described a polarization-modulated approach to RBS that enables entirely direct and reliable detection of true foveal fixation, with greatly enhanced signal-to-noise ratio and essentially independent of corneal birefringence (a confounding variable with all polarization-sensitive ophthalmic technology). Here, we describe the design and operation of a new pediatric vision screener that employs polarization-modulated, RBS-based strabismus detection and bull's eye focus detection with an improved target system, and demonstrate the feasibility of this new approach.

  7. Detection efficiency vs. cathode and anode separation in cylindrical vacuum photodiodes used for measuring x-rays from plasma focus device

    NASA Astrophysics Data System (ADS)

    Borthakur, T. K.; Talukdar, N.; Neog, N. K.; Rao, C. V. S.; Shyam, A.

    2011-10-01

    A qualitative study on the performance of cylindrical vacuum photodiodes (VPDs) for x-ray detection in plasma focus device has been carried out. Various parameters of VPD such as electrode's diameter, electrode's separation, and its sensitivity are experimentally tested in plasma focus environment. For the first time it is found experimentally that the electrode-separation in the lateral direction of the two coaxial electrodes of cylindrical VPD also plays an important role to increase the efficiency of the detector. The efficiency is found to be highest for the detector with smaller cathode-anode lateral gap (1.5 mm) with smaller photo cathode diameter (10 mm). A comparison between our VPD with PIN (BPX-65) diode as an x-ray detector has also been made.

  8. Detection efficiency vs. cathode and anode separation in cylindrical vacuum photodiodes used for measuring x-rays from plasma focus device.

    PubMed

    Borthakur, T K; Talukdar, N; Neog, N K; Rao, C V S; Shyam, A

    2011-10-01

    A qualitative study on the performance of cylindrical vacuum photodiodes (VPDs) for x-ray detection in plasma focus device has been carried out. Various parameters of VPD such as electrode's diameter, electrode's separation, and its sensitivity are experimentally tested in plasma focus environment. For the first time it is found experimentally that the electrode-separation in the lateral direction of the two coaxial electrodes of cylindrical VPD also plays an important role to increase the efficiency of the detector. The efficiency is found to be highest for the detector with smaller cathode-anode lateral gap (1.5 mm) with smaller photo cathode diameter (10 mm). A comparison between our VPD with PIN (BPX-65) diode as an x-ray detector has also been made. PMID:22047294

  9. New methodology for capillary electrophoresis with ESI-MS detection: Electrophoretic focusing on inverse electromigration dispersion gradient. High-sensitivity analysis of sulfonamides in waters.

    PubMed

    Malá, Zdena; Gebauer, Petr; Boček, Petr

    2016-09-01

    This article describes for the first time the combination of electrophoretic focusing on inverse electromigration dispersion (EMD) gradient, a new separation principle described in 2010, with electrospray-ionization (ESI) mass spectrometric detection. The separation of analytes along the electromigrating EMD profile proceeds so that each analyte is focused and concentrated within the profile at a particular position given by its pKa and ionic mobility. The proposed methodology combines this principle with the transport of the focused zones to the capillary end by superimposed electromigration, electroosmotic flow and ESI suction, and their detection by the MS detector. The designed electrolyte system based on maleic acid and 2,6-lutidine is suitable to create an inverse EMD gradient of required properties and its components are volatile enough to be compatible with the ESI interface. The characteristic properties of the proposed electrolyte system and of the formed inverse gradient are discussed in detail using calculated diagrams and computer simulations. It is shown that the system is surprisingly robust and allows sensitive analyses of trace amounts of weak acids in the pKa range between approx. 6 and 9. As a first practical application of electrophoretic focusing on inverse EMD gradient, the analysis of several sulfonamides in waters is reported. It demonstrates the potential of the developed methodology for fast and high-sensitivity analyses of ionic trace analytes, with reached LODs around 3 × 10(-9) M (0.8 ng mL(-1)) of sulfonamides in spiked drinking water without any sample pretreatment.

  10. New methodology for capillary electrophoresis with ESI-MS detection: Electrophoretic focusing on inverse electromigration dispersion gradient. High-sensitivity analysis of sulfonamides in waters.

    PubMed

    Malá, Zdena; Gebauer, Petr; Boček, Petr

    2016-09-01

    This article describes for the first time the combination of electrophoretic focusing on inverse electromigration dispersion (EMD) gradient, a new separation principle described in 2010, with electrospray-ionization (ESI) mass spectrometric detection. The separation of analytes along the electromigrating EMD profile proceeds so that each analyte is focused and concentrated within the profile at a particular position given by its pKa and ionic mobility. The proposed methodology combines this principle with the transport of the focused zones to the capillary end by superimposed electromigration, electroosmotic flow and ESI suction, and their detection by the MS detector. The designed electrolyte system based on maleic acid and 2,6-lutidine is suitable to create an inverse EMD gradient of required properties and its components are volatile enough to be compatible with the ESI interface. The characteristic properties of the proposed electrolyte system and of the formed inverse gradient are discussed in detail using calculated diagrams and computer simulations. It is shown that the system is surprisingly robust and allows sensitive analyses of trace amounts of weak acids in the pKa range between approx. 6 and 9. As a first practical application of electrophoretic focusing on inverse EMD gradient, the analysis of several sulfonamides in waters is reported. It demonstrates the potential of the developed methodology for fast and high-sensitivity analyses of ionic trace analytes, with reached LODs around 3 × 10(-9) M (0.8 ng mL(-1)) of sulfonamides in spiked drinking water without any sample pretreatment. PMID:27543034

  11. Capillary isoelectric focusing of microorganisms in the pH range 2-5 in a dynamically modified FS capillary with UV detection.

    PubMed

    Horká, Marie; Růzicka, Filip; Holá, Veronika; Slais, Karel

    2006-07-01

    The isoelectric points of many microbial cells lie within the pH range spanning from 1.5 to 4.5. In this work, we suggest a CIEF method for the separation of cells according to their isoelectric points in the pH range of 2-5. It includes the segmental injection of the sample pulse composed of the segment of the selected simple ampholytes, the segment of the bioanalytes and the segment of carrier ampholytes into fused silica capillaries dynamically modified by poly(ethylene glycole). This polymer dissolved in the catholyte, in the anolyte and in the injected sample pulse was used for a prevention of the bioanalyte adsorption on the capillary surface and for the reduction of the electroosmotic flow. Between each focusing run, the capillaries were washed with the mixture of acetone/ethanol to achieve the reproducible and efficient CIEF. In order to trace of pH gradients, low-molecular-mass pI markers were used. The mixed cultures of microorganisms, Escherichia coli CCM 3954, Candida albicans CCM 8180, Candida parapsilosis, Candida krusei, Candida glabrata, Candida tropicalis, CCM 8223, Proteus vulgaris, Klebsiela pneumoniae, Staphylococcus aureus CCM 3953, Streptococcus agalactiae CCM 6187, Enterococcus faecalis CCM 4224 and Staphylococcus epidermidis CCM 4418, were focused and separated by the CIEF method suggested here. This CIEF method enables the separation and detection of the microbes from the mixed cultures within several minutes. The minimum detectable number of microbial cells was less than 10(3).

  12. Improving the sensitivity of confocal laser induced fluorescence detection to the sub-picomolar scale for round capillaries by laterally shifting the laser focus point.

    PubMed

    Zhu, Ying; Chen, Niannian; Li, Qi; Fang, Qun

    2013-08-21

    This paper describes a simple and efficient approach to reduce the background level of confocal laser induced fluorescence (LIF) detection for round capillaries by laterally shifting the laser focus point. A phenomenon of spontaneous separation of the fluorescence and reflected laser beams at the pinhole of a confocal LIF system when the laser focus point deviates from the center of a capillary channel to the sides was observed for the first time. On the basis of this phenomenon, the reflected laser light from the capillary-air interfaces could be mostly eliminated with a spatial filtering pinhole. A comprehensive study on the phenomenon and optimization of the shift distance was carried out using both experimental and simulation methods. A best shift distance of ±20 μm was obtained, with which background intensity could be significantly reduced by 98.9%, while fluorescence intensity was only reduced by 25.7%, resulting in an improvement of signal-to-noise ratio of 8.3 times, compared with that at a shift distance of 0 μm usually used in most of the confocal LIF systems for round capillaries. A limit of detection of 66 fM was obtained for sodium fluorescein. To demonstrate its potential as an on-column sensitive detector for microscale separation systems, the present system was coupled with a capillary electrophoresis system for separation of four fluorescein isothiocyanate labeled amino acids with concentrations of 100 pM.

  13. Real-time monitoring of focused ultrasound blood-brain barrier opening via subharmonic acoustic emission detection: implementation of confocal dual-frequency piezoelectric transducers

    NASA Astrophysics Data System (ADS)

    Tsai, Chih-Hung; Zhang, Jia-Wei; Liao, Yi-Yi; Liu, Hao-Li

    2016-04-01

    Burst-tone focused ultrasound exposure in the presence of microbubbles has been demonstrated to be effective at inducing temporal and local opening of the blood-brain barrier (BBB), which promises significant clinical potential to deliver therapeutic molecules into the central nervous system (CNS). Traditional contrast-enhanced imaging confirmation after focused ultrasound (FUS) exposure serves as a post-operative indicator of the effectiveness of FUS-BBB opening, however, an indicator that can concurrently report the BBB status and BBB-opening effectiveness is required to provide effective feedback to implement this treatment clinically. In this study, we demonstrate the use of subharmonic acoustic emission detection with implementation on a confocal dual-frequency piezoelectric ceramic structure to perform real-time monitoring of FUS-BBB opening. A confocal dual-frequency (0.55 MHz/1.1 MHz) focused ultrasound transducer was designed. The 1.1 MHz spherically-curved ceramic was employed to deliver FUS exposure to induce BBB-opening, whereas the outer-ring 0.55 MHz ceramic was employed to detect the subharmonic acoustic emissions originating from the target position. In stage-1 experiments, we employed spectral analysis and performed an energy spectrum density (ESD) calculation. An optimized 0.55 MHz ESD level change was shown to effectively discriminate the occurrence of BBB-opening. Wideband acoustic emissions received from 0.55 MHz ceramics were also analyzed to evaluate its correlations with erythrocyte extravasations. In stage-2 real-time monitoring experiments, we applied the predetermined ESD change as a detection threshold in PC-controlled algorithm to predict the FUS exposure intra-operatively. In stage-1 experiment, we showed that subharmonic ESD presents distinguishable dynamics between intact BBB and opened BBB, and therefore a threshold ESD change level (5.5 dB) can be identified for BBB-opening prediction. Using this ESD change threshold detection as a

  14. Real-time monitoring of focused ultrasound blood-brain barrier opening via subharmonic acoustic emission detection: implementation of confocal dual-frequency piezoelectric transducers.

    PubMed

    Tsai, Chih-Hung; Zhang, Jia-Wei; Liao, Yi-Yi; Liu, Hao-Li

    2016-04-01

    Burst-tone focused ultrasound exposure in the presence of microbubbles has been demonstrated to be effective at inducing temporal and local opening of the blood-brain barrier (BBB), which promises significant clinical potential to deliver therapeutic molecules into the central nervous system (CNS). Traditional contrast-enhanced imaging confirmation after focused ultrasound (FUS) exposure serves as a post-operative indicator of the effectiveness of FUS-BBB opening, however, an indicator that can concurrently report the BBB status and BBB-opening effectiveness is required to provide effective feedback to implement this treatment clinically. In this study, we demonstrate the use of subharmonic acoustic emission detection with implementation on a confocal dual-frequency piezoelectric ceramic structure to perform real-time monitoring of FUS-BBB opening. A confocal dual-frequency (0.55 MHz/1.1 MHz) focused ultrasound transducer was designed. The 1.1 MHz spherically-curved ceramic was employed to deliver FUS exposure to induce BBB-opening, whereas the outer-ring 0.55 MHz ceramic was employed to detect the subharmonic acoustic emissions originating from the target position. In stage-1 experiments, we employed spectral analysis and performed an energy spectrum density (ESD) calculation. An optimized 0.55 MHz ESD level change was shown to effectively discriminate the occurrence of BBB-opening. Wideband acoustic emissions received from 0.55 MHz ceramics were also analyzed to evaluate its correlations with erythrocyte extravasations. In stage-2 real-time monitoring experiments, we applied the predetermined ESD change as a detection threshold in PC-controlled algorithm to predict the FUS exposure intra-operatively. In stage-1 experiment, we showed that subharmonic ESD presents distinguishable dynamics between intact BBB and opened BBB, and therefore a threshold ESD change level (5.5 dB) can be identified for BBB-opening prediction. Using this ESD change threshold detection as a

  15. Isoelectric Focusing of Serum Apolipoprotein C-III as a Sensitive Screening Method for the Detection of O-glycosylation Disturbances.

    PubMed

    Ondrušková, Nina; Honzík, Tomáš; Kytnarová, Jitka; Matoulek, Martin; Zeman, Jiří; Hansíková, Hana

    2015-01-01

    Apolipoprotein C-III (ApoC-III) is a glycoprotein carrying the most common O-linked glycan structure and is abundantly present in serum, what renders it a suitable marker for analysis of O-glycosylation abnormalities. Isoelectric focusing followed by a Western blot of ApoC-III, using PhastSystem™ Electrophoresis System (GE Healthcare), was introduced as a rather simple and rapid method for screening of certain subtypes of inherited glycosylation disorders. The study's aim was to establish this method in our laboratory, what included performing the analysis in a group of 170 healthy individuals to set the reference range of detected relative amounts of sialylated ApoC-III isoforms and to evaluate the gender- and age-dependent differences. A significant relative increase of asialo-ApoC-III with growing age was found. Secondly, we examined serum from patients with selected metabolic disorders and detected minor O-glycosylation changes in diseases such as Prader-Willi syndrome, PGM1 (phosphoglucomutase 1) or MAN1B (class 1B alpha-1,2-mannosidase) deficiency. Our results show that this method allows for a sensitive detection of ApoC-III O-glycosylation status, however this might be modulated by several factors (i.e. nutrition, medication) whose exact role remains to be determined. PMID:26093664

  16. Nested Polymerase Chain Reaction and Sequence- Based Detection of Leishmania Infection of Sand Flies in Recently Emerged Endemic Focus of Zoonotic Cutaneous Leishmaniasis, Southern Iran

    PubMed Central

    Azizi, Kourosh; Badzohreh, Abdollah; Sarkari, Bahador; Fakoorziba, Mohammad Reza; Kalantari, Mohsen; Moemenbellah-Fard, Mohammad Djaefar; Ali-Akbarpour, Mohsen

    2013-01-01

    Background: Geographical distribution of zoonotic cutaneous leishmaniasis (ZCL) has continuously been extended in recent years in Iran. The Beiza District is one of the newly-emerged endemic foci of ZCL in southern Iran. The main aim of the present study was to detect the vector(s) of ZCL in this area. Methods: To detect the fauna and vectors of ZCL in this district, sand flies were caught using sticky papers. Seventy randomly selected female sand flies out of 730 were molecularly investigated for Leishmania infection using species-specific nested polymerase chain reaction (PCR) assay between April and October 2010. Results: A total of 2543 sand flies were caught. The fauna was identified as 10 species (five Phlebotomus spp. and five Sergentomyia spp.). Phlebotomus papatasi was the most dominant species both indoors and outdoors (37.55% and 16.35 %, respectively). L. major was detected in 5 out of 48 investigated Phlebotomus papatasi (10.41%). Sequence-based characterization was carried out to confirm the PCR findings. The positive samples were shown to have 75-88% similarity with L. major sequences in GenBank. Conclusion: According to the findings of the present study, similar to the other foci of ZCL in Iran, P. papatasi is the proven and primary vector of CL. This study could be drawn upon for future strategy planning in this newly emerged endemic focus. PMID:24031105

  17. Combining a focused air-puff system with phase-sensitive optical coherence tomography for the detection of soft-tissue tumors based on elasticity measurement

    NASA Astrophysics Data System (ADS)

    Wang, Shang; Li, Jiasong; Vantipalli, Srilatha; Manapuram, Ravi Kiran; Ingram, Davis R.; Twa, Michael D.; Lazar, Alexander J.; Lev, Dina C.; Pollock, Raphael E.; Larin, Kirill V.

    2013-03-01

    We combine a focused air-puff system with phase-sensitive optical coherence tomography (PhS-OCT) to measure the elasticity of soft tissues. Surface waves (SWs) on soft tissues are induced by a low-pressure, short-duration air stream from an air-puff system and measured using a high-sensitivity PhS-OCT imaging system. Young's modulus of soft tissues can be quantified based on the group velocity of SWs. To precisely control the excitation pressure, the air-puff system was characterized with a high-resolution analog pressure transducer. We studied the feasibility of this method for the non-contact detection of soft-tissue tumors. Ex vivo human fat and myxoma were used for these pilot experiments. Results demonstrate that this optical non-contact technique can be used to differentiate soft-tissue tumors from normal tissues based on measurements of their elasticity.

  18. Noncontact measurement of elasticity for the detection of soft-tissue tumors using phase-sensitive optical coherence tomography combined with a focused air-puff system.

    PubMed

    Wang, Shang; Li, Jiasong; Manapuram, Ravi Kiran; Menodiado, Floredes M; Ingram, Davis R; Twa, Michael D; Lazar, Alexander J; Lev, Dina C; Pollock, Raphael E; Larin, Kirill V

    2012-12-15

    We report on an optical noncontact method for the detection of soft-tissue tumors based on the measurement of their elasticity. A focused air-puff system is used to excite surface waves (SWs) on soft tissues with transient static pressure. A high-speed phase-sensitive optical coherence tomography system is used to measure the SWs as they propagate from the point of excitation. To evaluate the stiffness of soft tissues, the Young's modulus is quantified based on the group velocity of SWs. Pilot experiments were performed on ex vivo human myxoma and normal fat. Results demonstrate the feasibility of the proposed method to measure elasticity and differentiate soft-tissue tumors from normal tissues.

  19. Fully integrated PDMS/SU-8/quartz microfluidic chip with a novel macroporous poly dimethylsiloxane (PDMS) membrane for isoelectric focusing of proteins using whole-channel imaging detection.

    PubMed

    Shameli, Seyed Mostafa; Elbuken, Caglar; Ou, Junjie; Ren, Carolyn L; Pawliszyn, Janusz

    2011-02-01

    A fully integrated polydimethylsiloxane (PDMS)/modified PDMS membrane/SU-8/quartz hybrid chip was developed for protein separation using isoelectric focusing (IEF) mechanism coupled with whole-channel imaging detection (WCID) method. This microfluidic chip integrates three components into one single chip: (i) modified PDMS membranes for separating electrolytes in the reservoirs from the sample in the microchannel and thus reducing pressure disturbance, (ii) SU-8 optical slit to block UV light (below 300 nm) outside the channel aiming to increase detection sensitivity, and (iii) injection and discharge capillaries for continuous operation. Integration of all these components on a single chip is challenging because it requires fabrication techniques for perfect bonding between different materials and is prone to leakage and blockage. This study has addressed all the challenges and presented a fully integrated chip, which is more robust with higher sensitivity than the previously developed IEF chips. This chip was tested by performing protein and pI marker separation. The separation results obtained in this chip were compared with that obtained in commercial cartridges. Side-by-side comparison validated the developed chip and fabrication techniques.

  20. Focused Screening and Treatment (FSAT): A PCR-Based Strategy to Detect Malaria Parasite Carriers and Contain Drug Resistant P. falciparum, Pailin, Cambodia

    PubMed Central

    Hoyer, Stefan; Nguon, Sokomar; Kim, Saorin; Habib, Najibullah; Khim, Nimol; Sum, Sarorn; Christophel, Eva-Maria; Bjorge, Steven; Thomson, Andrew; Kheng, Sim; Chea, Nguon; Yok, Sovann; Top, Samphornarann; Ros, Seyha; Sophal, Uth; Thompson, Michelle M.; Mellor, Steve; Ariey, Frédéric; Witkowski, Benoit; Yeang, Chhiang; Yeung, Shunmay; Duong, Socheat; Newman, Robert D.; Menard, Didier

    2012-01-01

    Recent studies have shown that Plasmodium falciparum malaria parasites in Pailin province, along the border between Thailand and Cambodia, have become resistant to artemisinin derivatives. To better define the epidemiology of P. falciparum populations and to assess the risk of the possible spread of these parasites outside Pailin, a new epidemiological tool named “Focused Screening and Treatment” (FSAT), based on active molecular detection of asymptomatic parasite carriers was introduced in 2010. Cross-sectional malariometric surveys using PCR were carried out in 20 out of 109 villages in Pailin province. Individuals detected as P. falciparum carriers were treated with atovaquone-proguanil combination plus a single dose of primaquine if the patient was non-G6PD deficient. Interviews were conducted to elicit history of cross-border travel that might contribute to the spread of artemisinin-resistant parasites. After directly observed treatment, patients were followed up and re-examined on day 7 and day 28. Among 6931 individuals screened, prevalence of P. falciparum carriers was less than 1%, of whom 96% were asymptomatic. Only 1.6% of the individuals had a travel history or plans to go outside Cambodia, with none of those tested being positive for P. falciparum. Retrospective analysis, using 2010 routine surveillance data, showed significant differences in the prevalence of asymptomatic carriers discovered by FSAT between villages classified as “high risk” and “low risk” based on malaria incidence data. All positive individuals treated and followed-up until day 28 were cured. No mutant-type allele related to atovaquone resistance was found. FSAT is a potentially useful tool to detect, treat and track clusters of asymptomatic carriers of P. falciparum along with providing valuable epidemiological information regarding cross-border movements of potential malaria parasite carriers and parasite gene flow. PMID:23049687

  1. An enzyme-linked immuno focus assay for rapid detection and enumeration, and a newborn mouse model for human non-polio enteroviruses associated with acute diarrhea.

    PubMed

    Rao, C Durga; Reddy, Harikrishna; Naidu, Jagadish R; Raghavendra, A; Radhika, N S; Karande, Anjali

    2015-11-01

    We have recently reported significant association of non-polio enteroviruses (NPEVs) with acute and persistent diarrhea (18-21% of total diarrheal cases), and non-diarrheal Increased Frequency of Bowel Movements (IFoBM-ND) (about 29% of the NPEV infections) in children and that the NPEV-associated diarrhea was as significant as rotavirus diarrhea. However, their diarrhea-causing potential is yet to be demonstrated in an animal model system. Since the determination of virus titers by the traditional plaque assay takes 4-7 days, there is a need for development of a rapid method for virus titer determination to facilitate active clinical research on enterovirus-associated diarrhea. The goal of this study is to develop a cell-based rapid detection and enumeration method and to demonstrate the diarrhea-inducing potential of purified and characterized non-polio enteroviruses, which were isolated from diarrheic children. Here we describe generation of monoclonal and polyclonal antibodies against purified strains belonging to different serotypes, and development of an enzyme-linked immuno focus assay (ELIFA) for detection and enumeration of live NPEV particles in clinical and purified virus samples, and a newborn mouse model for NPEV diarrhea. Plaque-purified NPVEs, belonging to different serotypes, isolated from children with diarrhea, were grown in cell culture and purified by isopycnic CsCl density gradient centrifugation. By ELIFA, NPEVs could be detected and enumerated within 12h post-infection. Our results demonstrated that Coxsackievirus B1 (CVB1) and CVB5 strains, isolated from diarrheic children, induced severe diarrhea in orally-inoculated 9-12 day-old mouse pups, fulfilling Koch's postulates. The methods described here would facilitate studies on NPEV-associated gastrointestinal disease.

  2. Prostatic cancer surveillance following whole-gland high-intensity focused ultrasound: comparison of MRI and prostate-specific antigen for detection of residual or recurrent disease

    PubMed Central

    Punwani, S; Emberton, M; Walkden, M; Sohaib, A; Freeman, A; Ahmed, H; Allen, C; Kirkham, A

    2012-01-01

    Objective This retrospective study compares dynamic contrast-enhanced (DCE) MRI with the serial prostate-specific antigen (PSA) measurement for detection of residual disease following whole-gland high-intensity focused ultrasound (HIFU) therapy of prostate cancer. Methods Patients in whom post-HIFU DCE-MRI was followed within 3 months by ultrasound-guided transrectal biopsy were selected from a local database. 26 patients met the study inclusion criteria. Serial PSA levels following HIFU and post-HIFU follow-up MRI were retrieved for each patient. Three radiologists unaware of other investigative results independently assessed post-HIFU MRI studies for the presence of cancer, scoring on a four-point scale (1, no disease; 2, probably no disease; 3, probably residual disease; and 4, residual disease). Sensitivity, specificity and receiver operating characteristic (ROC) analysis were performed for each reader, post-HIFU PSA nadir and pre-biopsy PSA level thresholds of >0.2 and >0.5 ng ml−1. Results The sensitivity of DCE-MRI for detection of residual disease for the three readers ranged between 73% and 87%, and the specificity between 73% and 82%. There was good agreement between readers (κ=0.69–0.77). The sensitivity and specificity of PSA thresholds was 60–87% and 73–100%, respectively. The area under the ROC curve was greatest for pre-biopsy PSA (0.95). Conclusion DCE-MRI performed following whole-gland HIFU has similar sensitivity and specificity and ROC performance to serial PSA measurements for detection of residual or recurrent disease. PMID:22253342

  3. Performance assessment of HIFU lesion detection by harmonic motion imaging for focused ultrasound (HMIFU): a 3-D finite-element-based framework with experimental validation.

    PubMed

    Hou, Gary Y; Luo, Jianwen; Marquet, Fabrice; Maleke, Caroline; Vappou, Jonathan; Konofagou, Elisa E

    2011-12-01

    Harmonic motion imaging for focused ultrasound (HMIFU) is a novel high-intensity focused ultrasound (HIFU) therapy monitoring method with feasibilities demonstrated in vitro, ex vivo and in vivo. Its principle is based on amplitude-modulated (AM) - harmonic motion imaging (HMI), an oscillatory radiation force used for imaging the tissue mechanical response during thermal ablation. In this study, a theoretical framework of HMIFU is presented, comprising a customized nonlinear wave propagation model, a finite-element (FE) analysis module and an image-formation model. The objective of this study is to develop such a framework to (1) assess the fundamental performance of HMIFU in detecting HIFU lesions based on the change in tissue apparent elasticity, i.e., the increasing Young's modulus, and the HIFU lesion size with respect to the HIFU exposure time and (2) validate the simulation findings ex vivo. The same HMI and HMIFU parameters as in the experimental studies were used, i.e., 4.5-MHz HIFU frequency and 25 Hz AM frequency. For a lesion-to-background Young's modulus ratio of 3, 6 and 9, the FE and estimated HMI displacement ratios were equal to 1.83, 3.69 and 5.39 and 1.65, 3.19 and 4.59, respectively. In experiments, the HMI displacement followed a similar increasing trend of 1.19, 1.28 and 1.78 at 10-s, 20-s and 30-s HIFU exposure, respectively. In addition, moderate agreement in lesion size growth was found in both simulations (16.2, 73.1 and 334.7 mm(2)) and experiments (26.2, 94.2 and 206.2 mm(2)). Therefore, the feasibility of HMIFU for HIFU lesion detection based on the underlying tissue elasticity changes was verified through the developed theoretical framework, i.e., validation of the fundamental performance of the HMIFU system for lesion detection, localization and quantification, was demonstrated both theoretically and ex vivo.

  4. Resuscitative Long-Bone Sonography for the Clinician: Usefulness and Pitfalls of Focused Clinical Ultrasound to Detect Long-Bone Fractures During Trauma Resuscitation.

    PubMed

    Al-Kadi, Azzam S; Gillman, Lawrence M; Ball, Chad G; Panebianco, Nova L; Kirkpatrick, Andrew W

    2009-08-01

    Bone has one of the highest acoustic densities (AD) in the human body. Traditionally, bone has been considered to be a hindrance to the use of ultrasound (US), as US waves are reflected by the dense matrix and obscure underlying structures. The intense wave reflection, however, can clearly illustrate the cortical bony anatomy of long bones, making cortical disruption obvious. Ultrasound can be used at the bedside concurrently with the overall trauma resuscitation, and may potentially limit the patient's and treating team's exposure to ionizing radiation, corroborate clinical findings, and augment procedural success. The extended focused assessment with sonography for trauma (EFAST) is an essential tool in the resuscitation of severe torso trauma, frequently demonstrating intra- pericardial and intra-peritoneal fluid, inferring hemo/pneumothoraces, and demonstrating cardiac function. Although it is typically considered as a diagnosis of exclusion, multiple long-bone fractures may be a source of shock and can be quickly confirmed at the bedside with EFAST. Further, the early detection of long-bone fractures can also aid in the early stabilization of severely injured patients. Sonographic evaluation for long-bone fractures may be particularly useful in austere environments where other imaging modalities are limited, such as in the battlefield, developing world, and space. While prospective study has been limited, selected series have demonstrated high accuracy among both physician and para-medical clinicians in detecting long-bone fractures. Pitfalls in this technique include reduced accuracy with the small bones of the hands and feet, as well as great reliance on user experience.

  5. Ion focusing

    DOEpatents

    Cooks, Robert Graham; Baird, Zane; Peng, Wen-Ping

    2015-11-10

    The invention generally relates to apparatuses for focusing ions at or above ambient pressure and methods of use thereof. In certain embodiments, the invention provides an apparatus for focusing ions that includes an electrode having a cavity, at least one inlet within the electrode configured to operatively couple with an ionization source, such that discharge generated by the ionization source is injected into the cavity of the electrode, and an outlet. The cavity in the electrode is shaped such that upon application of voltage to the electrode, ions within the cavity are focused and directed to the outlet, which is positioned such that a proximal end of the outlet receives the focused ions and a distal end of the outlet is open to ambient pressure.

  6. Electrophoretic Focusing

    NASA Technical Reports Server (NTRS)

    Snyder, Robert S.

    2001-01-01

    Electrophoretic focusing is a new method of continuous flow electrophoresis that introduces precision flow control to achieve high resolution separations. The electric field is applied perpendicular to an incoming sample lamina and buffer but also perpendicular to the broad faces of the thin rectangular chamber. A uniform fluid cross-flow then enters and exits the separation chamber through the same broad faces which are porous. A balance is achieved by adjusting either the electric field or the cross-flow so the desired sample fraction with its specific migration velocity encounters an opposing flow of the same velocity. Applying an electric field transverse to the incoming sample lamina and opposing this field with a carefully configured buffer flow, a sample constituent can be selected and focused into a narrow stream for subsequent analysis. Monotonically changing either electric field or buffer cross-flow will yield a scan of all constituents of the sample. Stopping the scan increases the collection time for minor constituents to improve their analysis. Using the high voltage gradients and/or cross-flow to rapidly deflect extraneous sample through the porous screens and into either of the side (purge) chambers, the selected sample is focused in the center plane of the separation chamber and collected without contact or interaction with the separation chamber walls. Results will be presented on the separation of a range of materials including dyes, proteins, and monodisperse polystyrene latexes. Sources of sample dispersion inherent in other electrokinetic techniques will be shown to be negligible for a variety of sample concentrations, buffer properties and operating conditions.

  7. Semantic Focus and Sentence Comprehension.

    ERIC Educational Resources Information Center

    Cutler, Anne; Fodor, Jerry A.

    1979-01-01

    Reaction time to detect a phoneme target in a sentence was faster when the target-containing word formed part of the semantic focus of the sentence. Sentence understanding was facilitated by rapid identification of focused information. Active search for accented words can be interpreted as a search for semantic focus. (Author/RD)

  8. A Systematic Review of Bovine Respiratory Disease Diagnosis Focused on Diagnostic Confirmation, Early Detection, and Prediction of Unfavorable Outcomes in Feedlot Cattle.

    PubMed

    Wolfger, Barbara; Timsit, Edouard; White, Brad J; Orsel, Karin

    2015-11-01

    A large proportion of newly arrived feedlot cattle are affected with bovine respiratory disease (BRD). Economic losses could be reduced by accurate, early detection. This review evaluates the available literature regarding BRD confirmatory diagnostic tests, early detection methods, and modalities to estimate post-therapeutic prognosis or predict unfavorable or fatal outcomes. Scientific evidence promotes the use of haptoglobin to confirm BRD status. Feeding behavior, infrared thermography, and reticulorumen boluses are promising methods. Retrospective analyses of routinely collected treatment and cohort data can be used to identify cattle at risk of unfavorable outcome. Other methods have been reviewed but require further study.

  9. Investigation into the use of smartphone as a machine vision device for engineering metrology and flaw detection, with focus on drilling

    NASA Astrophysics Data System (ADS)

    Razdan, Vikram; Bateman, Richard

    2015-05-01

    This study investigates the use of a Smartphone and its camera vision capabilities in Engineering metrology and flaw detection, with a view to develop a low cost alternative to Machine vision systems which are out of range for small scale manufacturers. A Smartphone has to provide a similar level of accuracy as Machine Vision devices like Smart cameras. The objective set out was to develop an App on an Android Smartphone, incorporating advanced Computer vision algorithms written in java code. The App could then be used for recording measurements of Twist Drill bits and hole geometry, and analysing the results for accuracy. A detailed literature review was carried out for in-depth study of Machine vision systems and their capabilities, including a comparison between the HTC One X Android Smartphone and the Teledyne Dalsa BOA Smart camera. A review of the existing metrology Apps in the market was also undertaken. In addition, the drilling operation was evaluated to establish key measurement parameters of a twist Drill bit, especially flank wear and diameter. The methodology covers software development of the Android App, including the use of image processing algorithms like Gaussian Blur, Sobel and Canny available from OpenCV software library, as well as designing and developing the experimental set-up for carrying out the measurements. The results obtained from the experimental set-up were analysed for geometry of Twist Drill bits and holes, including diametrical measurements and flaw detection. The results show that Smartphones like the HTC One X have the processing power and the camera capability to carry out metrological tasks, although dimensional accuracy achievable from the Smartphone App is below the level provided by Machine vision devices like Smart cameras. A Smartphone with mechanical attachments, capable of image processing and having a reasonable level of accuracy in dimensional measurement, has the potential to become a handy low-cost Machine vision

  10. Molecular detection of Leishmania in phlebotomine sand flies (Diptera: Psychodidae) from a cutaneous leishmaniasis focus atXakriabá Indigenous Reserve, Brazil.

    PubMed

    Rêgo, Felipe Dutra; Rugani, Jeronimo Marteleto Nunes; Shimabukuro, Paloma Helena Fernandes; Tonelli, Gabriel Barbosa; Quaresma, Patrícia Flávia; Gontijo, Célia Maria Ferreira

    2015-01-01

    Autochthonous cases of American cutaneous leishmaniasis (ACL) have been reported since 2001 in the Xakriabá Indigenous Reserve located in the municipality of São João das Missões in northern Minas Gerais state, Brazil. In order to study the presence of Leishmania DNA in phlebotomine sand flies, six entomological collections were carried out from July 2008 through July 2009, using 40 light traps placed in peridomicile areas of 20 randomly selected houses. From October 2011 through August 2012, another six collections were carried out with 20 light traps distributed among four trails (five traps per trail) selected for a previous study of wild and synanthropic hosts of Leishmania. A total of 4,760 phlebotomine specimens were collected belonging to ten genera and twenty-three species. Single female specimens or pools with up to ten specimens of the same locality, species and date, for Leishmania detection by molecular methods. Species identification of parasites was performed with ITS1 PCR-RFLP using HaeIII enzyme and genetic sequencing for SSU rRNA target. The presence of Leishmania DNA was detected in eleven samples from peridomicile areas: Lu. longipalpis (two), Nyssomyia intermedia (four), Lu. renei (two), Lu. ischnacantha, Micropygomyia goiana and Evandromyia lenti (one pool of each specie). The presence of Leishmania DNA was detected in twelve samples from among the trails: Martinsmyia minasensis (six), Ny. intermedia (three), Mi. peresi (two) and Ev. lenti (one). The presence of Leishmania infantum DNA in Lu. longipalpis and Leishmania braziliensis DNA in Ny. intermediasupport the epidemiological importance of these species of sand flies in the cycle of visceral and cutaneous leishmaniasis, respectively. The results also found other species associated with Leishmania DNA, such as Mt. minasensis and Ev. lenti, which may participate in a wild and/or synanthropic cycle of Leishmania transmission in the studied area.

  11. Molecular detection and identification of Leishmania spp. in naturally infected Phlebotomus tobbi and Sergentomyia dentata in a focus of human and canine leishmaniasis in western Turkey.

    PubMed

    Özbel, Yusuf; Karakuş, Mehmet; Arserim, Suha K; Kalkan, Şaban Orçun; Töz, Seray

    2016-03-01

    Human visceral leishmaniasis (VL) is reported from 38 provinces of Turkey and dogs are accepted as main reservoir hosts. Kuşadası town, belonging to Aydın province and located in western part of Turkey, is endemic for human and canine visceral leishmaniasis caused by Leishmania infantum MON1 and MON98. In this study, phlebotomine survey was conducted to determine the vector sand fly species and to identify sand fly blood meal sources. In August and September 2012, 1027 sand fly specimens were caught using CDC light traps. Eight Phlebotomus and two Sergentomyia species with the dominancy of Phlebotomus tobbi (61.34%) were detected. A total of 622 female sand flies (571 Phlebotomus; 51 Sergentomyia) were checked for Leishmania infection by direct dissection of the midgut. The half of the midgut content was inoculated into NNN culture for isolation of the parasite. Leishmania species-specific ITS1 real time PCR, conventional PCR assays of ITS1 and hsp70 genes and subsequent sequencing were performed from extracted DNAs. A region of cytochrome b (cyt-b) gene of vertebrates based PCR was used to determine the source of blood meal of sand flies. In microscopical examinations, two female specimens (0.32%) were found naturally infected with high number and different stages of promastigotes. No growth was observed in NNN culture but Leishmania DNA was obtained from both specimens. First positive specimen was identified as P. tobbi and L. infantum DNA was detected. Second specimen was Sergentomyia dentata, but Leishmania DNA could not be identified on species level. A total of 16 blood-fed female P. tobbi specimens were used for blood meal analysis and eight, three and one specimens were positive for human, dog and mouse, respectively. This is the first detection of Leishmania promastigotes using microscopical examination in P. tobbi and S. dentata in human and canine visceral leishmaniasis endemic area in western part of Turkey. Our results indicate that, (i) P. tobbi is

  12. Molecular detection and identification of Leishmania spp. in naturally infected Phlebotomus tobbi and Sergentomyia dentata in a focus of human and canine leishmaniasis in western Turkey.

    PubMed

    Özbel, Yusuf; Karakuş, Mehmet; Arserim, Suha K; Kalkan, Şaban Orçun; Töz, Seray

    2016-03-01

    Human visceral leishmaniasis (VL) is reported from 38 provinces of Turkey and dogs are accepted as main reservoir hosts. Kuşadası town, belonging to Aydın province and located in western part of Turkey, is endemic for human and canine visceral leishmaniasis caused by Leishmania infantum MON1 and MON98. In this study, phlebotomine survey was conducted to determine the vector sand fly species and to identify sand fly blood meal sources. In August and September 2012, 1027 sand fly specimens were caught using CDC light traps. Eight Phlebotomus and two Sergentomyia species with the dominancy of Phlebotomus tobbi (61.34%) were detected. A total of 622 female sand flies (571 Phlebotomus; 51 Sergentomyia) were checked for Leishmania infection by direct dissection of the midgut. The half of the midgut content was inoculated into NNN culture for isolation of the parasite. Leishmania species-specific ITS1 real time PCR, conventional PCR assays of ITS1 and hsp70 genes and subsequent sequencing were performed from extracted DNAs. A region of cytochrome b (cyt-b) gene of vertebrates based PCR was used to determine the source of blood meal of sand flies. In microscopical examinations, two female specimens (0.32%) were found naturally infected with high number and different stages of promastigotes. No growth was observed in NNN culture but Leishmania DNA was obtained from both specimens. First positive specimen was identified as P. tobbi and L. infantum DNA was detected. Second specimen was Sergentomyia dentata, but Leishmania DNA could not be identified on species level. A total of 16 blood-fed female P. tobbi specimens were used for blood meal analysis and eight, three and one specimens were positive for human, dog and mouse, respectively. This is the first detection of Leishmania promastigotes using microscopical examination in P. tobbi and S. dentata in human and canine visceral leishmaniasis endemic area in western part of Turkey. Our results indicate that, (i) P. tobbi is

  13. Spatiotemporal drug delivery using laser-generated-focused ultrasound system.

    PubMed

    Di, Jin; Kim, Jinwook; Hu, Quanyin; Jiang, Xiaoning; Gu, Zhen

    2015-12-28

    Laser-generated-focused ultrasound (LGFU) holds promise for the high-precision ultrasound therapy owing to its tight focal spot, broad frequency band, and stable excitation with minimal ultrasound-induced heating. We here report the development of the LGFU as a stimulus for promoted drug release from microgels integrated with drug-loaded polymeric nanoparticles. The pulsed waves of ultrasound, generated by a carbon black/polydimethylsiloxane (PDMS)-photoacoustic lens, were introduced to trigger the drug release from alginate microgels encapsulated with drug-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles. We demonstrated the antibacterial capability of this drug delivery system against Escherichia coli by the disk diffusion method, and antitumor efficacy toward the HeLa cell-derived tumor spheroids in vitro. This novel LGFU-responsive drug delivery system provides a simple and remote approach to precisely control the release of therapeutics in a spatiotemporal manner and potentially suppress detrimental effects to the surrounding tissue, such as thermal ablation.

  14. Synthesis of grafted phosphorylcholine polymer layers as specific recognition ligands for C-reactive protein focused on grafting density and thickness to achieve highly sensitive detection.

    PubMed

    Kamon, Yuri; Kitayama, Yukiya; Itakura, Akiko N; Fukazawa, Kyoko; Ishihara, Kazuhiko; Takeuchi, Toshifumi

    2015-04-21

    We studied the effects of layer thickness and grafting density of poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) thin layers as specific ligands for the highly sensitive binding of C-reactive protein (CRP). PMPC layer thickness was controlled by surface-initiated activators generated by electron transfer for atom transfer radical polymerization (AGET ATRP). PMPC grafting density was controlled by utilizing mixed self-assembled monolayers with different incorporation ratios of the bis[2-(2-bromoisobutyryloxy)undecyl] disulfide ATRP initiator, as modulated by altering the feed molar ratio with (11-mercaptoundecyl)tetra(ethylene glycol). X-ray photoelectron spectroscopy and ellipsometry measurements were used to characterize the modified surfaces. PMPC grafting densities were estimated from polymer thickness and the molecular weight obtained from sacrificial initiator during surface-initiated AGET ATRP. The effects of thickness and grafting density of the obtained PMPC layers on CRP binding performance were investigated using surface plasmon resonance employing a 10 mM Tris-HCl running buffer containing 140 mM NaCl and 2 mM CaCl2 (pH 7.4). Furthermore, the non-specific binding properties of the obtained layers were investigated using human serum albumin (HSA) as a reference protein. The PMPC layer which has 4.6 nm of thickness and 1.27 chains per nm(2) of grafting density showed highly sensitive CRP detection (limit of detection: 4.4 ng mL(-1)) with low non-specific HSA adsorption, which was improved 10 times than our previous report of 50 ng mL(-1). PMID:25783194

  15. Synthesis of grafted phosphorylcholine polymer layers as specific recognition ligands for C-reactive protein focused on grafting density and thickness to achieve highly sensitive detection.

    PubMed

    Kamon, Yuri; Kitayama, Yukiya; Itakura, Akiko N; Fukazawa, Kyoko; Ishihara, Kazuhiko; Takeuchi, Toshifumi

    2015-04-21

    We studied the effects of layer thickness and grafting density of poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) thin layers as specific ligands for the highly sensitive binding of C-reactive protein (CRP). PMPC layer thickness was controlled by surface-initiated activators generated by electron transfer for atom transfer radical polymerization (AGET ATRP). PMPC grafting density was controlled by utilizing mixed self-assembled monolayers with different incorporation ratios of the bis[2-(2-bromoisobutyryloxy)undecyl] disulfide ATRP initiator, as modulated by altering the feed molar ratio with (11-mercaptoundecyl)tetra(ethylene glycol). X-ray photoelectron spectroscopy and ellipsometry measurements were used to characterize the modified surfaces. PMPC grafting densities were estimated from polymer thickness and the molecular weight obtained from sacrificial initiator during surface-initiated AGET ATRP. The effects of thickness and grafting density of the obtained PMPC layers on CRP binding performance were investigated using surface plasmon resonance employing a 10 mM Tris-HCl running buffer containing 140 mM NaCl and 2 mM CaCl2 (pH 7.4). Furthermore, the non-specific binding properties of the obtained layers were investigated using human serum albumin (HSA) as a reference protein. The PMPC layer which has 4.6 nm of thickness and 1.27 chains per nm(2) of grafting density showed highly sensitive CRP detection (limit of detection: 4.4 ng mL(-1)) with low non-specific HSA adsorption, which was improved 10 times than our previous report of 50 ng mL(-1).

  16. Detection of Leishmania major DNA within wild caught Phlebotomus papatasi and species composition of sand flies in endemic focus of cutaneous leishmaniasis, in western Iran.

    PubMed

    Vahabi, A; Rassi, Y; Oshaghi, M A; Sayyadi, M; Rafizadeh, S

    2016-03-01

    Cutaneous leishmaniasis is one of the most important public health problem in many developing countries. The present study was conducted to determine the vector(s), the parasite and the species composition of sand flies in the Dehloran County during May-November 2012. Sand flies were collected by sticky traps and mounted in Puri's medium for species identification. Polymerase chain reaction (PCR) techniques of kDNA, ITS1-rDNA, followed by restriction fragment length polymorphism (RFLP) were used for identification of DNA of Leishmania parasites in infected sand flies. A total of 82443 specimens comprising 15 species of sand flies (5 Phlebotomus and 10 Sergentomyia) were collected and identified. The species of Phlebotomus papatasi was dominant in outdoor and indoor resting places. Among the 280 specimens of female P. papatasi tested by PCR of kDNA, ITS1-rDNA genes of the parasite followed by RFLP, only 5 of them (1.8 %) were positive to Leishmania major parasites. This is the first molecular detection of leishmania infection of P. papatasi to L. major in this region. The results indicated that, P. papatasi was only species found infected by L. major and the principal vector of disease agent to human. PMID:27065601

  17. Chromosome-Directed PCR-Based Detection and Quantification of Bacillus cereus Group Members with Focus on B. thuringiensis Serovar israelensis Active against Nematoceran Larvae.

    PubMed

    Schneider, Salome; Hendriksen, Niels B; Melin, Petter; Lundström, Jan O; Sundh, Ingvar

    2015-08-01

    Bacillus thuringiensis serovar israelensis is a wide-spread soil bacterium affiliated with the B. cereus group (Bcg) and is widely used in biocontrol products applied against mosquito and black fly larvae. For monitoring and quantification of applied B. thuringiensis serovar israelensis and its effect on indigenous B. thuringiensis serovar israelensis and Bcg assemblages, efficient and reliable tools are essential. The abundance and properties of B. thuringiensis serovar israelensis strains in the environment traditionally have been investigated with cultivation-dependent techniques, which are hampered by low sensitivity and the morphological similarity between B. cereus and B. thuringiensis. Currently available PCR-based detection and quantification tools target markers located on plasmids. In this study, a new cultivation-independent PCR-based method for efficient and specific quantification of B. thuringiensis serovar israelensis and Bcg is presented, utilizing two sets of PCR primers targeting the bacterial chromosome. Sequence database searches and empirical tests performed on target and nontarget species, as well as on bulk soil DNA samples, demonstrated that this diagnostic tool is specific for B. thuringiensis serovar israelensis and Bcg. The method will be useful for comparisons of Bcg and B. thuringiensis serovar israelensis abundances in the same samples. Moreover, the effect of B. thuringiensis serovar israelensis-based insecticide application on the total Bcg assemblages, including indigenous populations, can be investigated. This type of information is valuable in risk assessment and policy making for use of B. thuringiensis serovar israelensis in the environment.

  18. Chromosome-Directed PCR-Based Detection and Quantification of Bacillus cereus Group Members with Focus on B. thuringiensis Serovar israelensis Active against Nematoceran Larvae

    PubMed Central

    Hendriksen, Niels B.; Melin, Petter; Lundström, Jan O.; Sundh, Ingvar

    2015-01-01

    Bacillus thuringiensis serovar israelensis is a wide-spread soil bacterium affiliated with the B. cereus group (Bcg) and is widely used in biocontrol products applied against mosquito and black fly larvae. For monitoring and quantification of applied B. thuringiensis serovar israelensis and its effect on indigenous B. thuringiensis serovar israelensis and Bcg assemblages, efficient and reliable tools are essential. The abundance and properties of B. thuringiensis serovar israelensis strains in the environment traditionally have been investigated with cultivation-dependent techniques, which are hampered by low sensitivity and the morphological similarity between B. cereus and B. thuringiensis. Currently available PCR-based detection and quantification tools target markers located on plasmids. In this study, a new cultivation-independent PCR-based method for efficient and specific quantification of B. thuringiensis serovar israelensis and Bcg is presented, utilizing two sets of PCR primers targeting the bacterial chromosome. Sequence database searches and empirical tests performed on target and nontarget species, as well as on bulk soil DNA samples, demonstrated that this diagnostic tool is specific for B. thuringiensis serovar israelensis and Bcg. The method will be useful for comparisons of Bcg and B. thuringiensis serovar israelensis abundances in the same samples. Moreover, the effect of B. thuringiensis serovar israelensis-based insecticide application on the total Bcg assemblages, including indigenous populations, can be investigated. This type of information is valuable in risk assessment and policy making for use of B. thuringiensis serovar israelensis in the environment. PMID:25979887

  19. Low-intensity pulsed ultrasound induces apoptosis in osteoclasts: Fish scales are a suitable model for the analysis of bone metabolism by ultrasound.

    PubMed

    Suzuki, Nobuo; Hanmoto, Taizo; Yano, Sachiko; Furusawa, Yukihiro; Ikegame, Mika; Tabuchi, Yoshiaki; Kondo, Takashi; Kitamura, Kei-ichiro; Endo, Masato; Yamamoto, Toshio; Sekiguchi, Toshio; Urata, Makoto; Mikuni-Takagaki, Yuko; Hattori, Atsuhiko

    2016-05-01

    Using fish scales in which osteoclasts and osteoblasts coexist on the calcified bone matrix, we examined the effects of low-intensity pulsed ultrasound (LIPUS) on both osteoclasts and osteoblasts. At 3h of incubation after LIPUS treatment, osteoclastic markers such as tartrate-resistant acid phosphatase (TRAP) and cathepsin K mRNA expressions decreased significantly while mRNA expressions of osteoblastic markers, osteocalcin, distal-less homeobox 5, runt-related transcription factor 2a, and runt-related transcription factor 2b, increased significantly. At 6 and 18h of incubation, however, both osteoclastic and osteoblastic marker mRNA expression did not change at least present conditions. Using GeneChip analysis of zebrafish scales treated with LIPUS, we found that cell death-related genes were upregulated with LIPUS treatment. Real-time PCR analysis indicated that the expression of apoptosis-related genes also increased significantly. To confirm the involvement of apoptosis in osteoclasts with LIPUS, osteoclasts were induced by autotransplanting scales in goldfish. Thereafter, the DNA fragmentation associated with apoptosis was detected in osteoclasts using the TUNEL (TdT-mediated dUTP nick end labeling) method. The multi-nuclei of TRAP-stained osteoclasts in the scales were labeled with TUNEL. TUNEL staining showed that the number of apoptotic osteoclasts in goldfish scales was significantly elevated by treatment with LIPUS at 3h of incubation. Thus, we are the first to demonstrate that LIPUS directly functions to osteoclasts and to conclude that LIPUS directly causes apoptosis in osteoclasts shortly after exposure. PMID:26850473

  20. Usefulness of the rK39-Immunochromatographic Test, Direct Agglutination Test, and Leishmanin Skin Test for Detecting Asymptomatic Leishmania Infection in Children in a New Visceral Leishmaniasis Focus in Amhara State, Ethiopia

    PubMed Central

    Gadisa, Endalamaw; Custodio, Estefanía; Cañavate, Carmen; Sordo, Luis; Abebe, Zelalem; Nieto, Javier; Chicharro, Carmen; Aseffa, Abraham; Yamuah, Lawrence; Engers, Howard; Moreno, Javier; Cruz, Israel

    2012-01-01

    In areas where visceral leishmaniasis is anthroponotic, asymptomatically infected patients may play a role in transmission. Additionally, the number of asymptomatic patients in a disease-endemic area will also provide information on transmission dynamics. Libo Kemkem and Fogera districts (Amhara State, Ethiopia) are now considered newly established areas to which visceral leishmaniasis is endemic. In selected villages in these districts, we conducted a study to assess the usefulness of different approaches to estimate the asymptomatic infection rate. Of 605 participants, the rK39 immunochromatographic test was able to detect asymptomatic infection in 1.5% (9 of 605), direct agglutination test in 5.3% (32 of 605), and leishmanin skin test in 5.6% (33 of 589); the combined use of serologic methods and leishmanin skin test enabled detecting asymptomatic infection in 10.1% (61 of 605). We conclude that the best option to detect asymptomatic infection in this new visceral leishmaniasis–endemic focus is the combined use of the direct agglutination test and the leishmanin skin test. PMID:22556076

  1. Comprehensive two-dimensional separation system by coupling capillary reverse-phase liquid chromatography to capillary isoelectric focusing for peptide and protein mapping with laser-induced fluorescence detection.

    PubMed

    Mao, Yu; Zhang, Xiangmin

    2003-09-01

    A comprehensive two-dimensional (2-D) separation system, coupling capillary reverse-phase liquid chromatography (cRPLC) to capillary isoelectric focusing (CIEF), is described for protein and peptide mapping. cRPLC, the first dimension, provided high-resolution separations for salt-free proteins. CIEF, the second dimension with an orthogonal mechanism to cRPLC afforded excellent resolution capability for proteins with efficient protein enrichment. Since all sample fractions in cRPLC effluents could be transferred to the CIEF dimensions, the combination of the two high-efficiency separations resulted in maximal separation capabilities of each dimension. Separation effectiveness of this approach was demonstrated using complex protein/peptide samples, such as yeast cytosol and a BSA tryptic digest. A peak capacity of more than 10 000 had been achieved. A laser-induced fluorescence (LIF) detector, developed for this system, allowed for high-sensitive detection, with a fmol level of peptide detection for the BSA digest. FITC and BODIPY maleimide were used to tag the proteins, and the latter was found better both for separation and detection in our 2-D system.

  2. Ultrasound induced aqueous polycyclic aromatic hydrocarbon reactivity.

    PubMed

    Wheat, P E; Tumeo, M A

    1997-01-01

    An investigation to determine the ability of ultrasonic radiation to chemically alter polycyclic aromatic hydrocarbons (PAHs) in aqueous solution has been conducted. The data indicate that chemical alteration of PAHs can be induced under intense ultrasonic treatment. The extent and outcome of reaction is a function of irridation time and aqueous solution parameters. Reaction products were analysed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Reaction products from ultrasonic treatment of aqueous solutions of biphenyl include ortho, meta, and para-1,1 biphenols. The principal product from ultrasonic treatment of aqueous phenanthrene solutions appears to be a phenanthrene-diol. The number and composition of reaction products for both PAHs tested suggest that a free radical mechanism is likely during aqueous high intensity ultrasonic treatment. The use of ultrasound to treat PAH contaminated aqueous solutions in tandem with other methodologies appears promising. However, the toxicity of reaction products produced by treatment remains to be determined. PMID:11233926

  3. Pulsed high intensity focused ultrasound (pHIFU) enhances delivery of doxorubicin in a preclinical model of pancreatic cancer

    PubMed Central

    Li, Tong; Wang, Yak-Nam; Khokhlova, Tatiana D.; D’Andrea, Samantha; Starr, Frank; Chen, Hong; McCune, Jeannine S.; Risler, Linda J.; Mashadi-Hossein, Afshin; Hwang, Joo Ha

    2015-01-01

    Pancreatic cancer is characterized by extensive stromal desmoplasia which decreases blood perfusion and impedes chemotherapy delivery. Breaking the stromal barrier could both increase perfusion and permeabilize the tumor, enhancing chemotherapy penetration. Mechanical disruption of the stroma can be achieved using ultrasound-induced bubble activity – cavitation. Cavitation is also known to result in microstreaming and could have the added benefit of actively enhancing diffusion into the tumors. Here, we report the ability to enhance chemotherapeutic drug doxorubicin (Dox) penetration using ultrasound-induced cavitation in a genetically engineered mouse model (KPC mouse) of pancreatic ductal adenocarcinoma. To induce localized inertial cavitation in pancreatic tumors, pulsed high intensity focused ultrasound (pHIFU) was used either during or before doxorubicin administration to elucidate the mechanisms of enhanced drug delivery (active versus passive drug diffusion). For both types, the pHIFU exposures which were associated with high cavitation activity resulted in disruption of the highly fibrotic stromal matrix and enhanced the normalized Dox concentration by up to 4.5 fold compared to controls. Furthermore, normalized Dox concentration was associated with the cavitation metrics (p < 0.01), indicating that high and sustained cavitation results in increased chemotherapy penetration. No significant difference between the outcomes of the two types, i.e., Dox infusion during or after pHIFU treatment, was observed, suggesting that passive diffusion into previously permeabilized tissue is the major mechanism for the increase in drug concentration. Together, the data indicate that pHIFU treatment of pancreatic tumors when resulting in high and sustained cavitation can efficiently enhance chemotherapy delivery to pancreatic tumors. PMID:26216548

  4. "Only" and Focus.

    ERIC Educational Resources Information Center

    Vallduvi, Enric

    The relationship of the word "only," one of a class of words known as scalar particles, focus adverbs, focus inducers, or focus-sensitive particles, with the "focus" of the sentence is examined. It is suggested, based on analysis of discourse structure, that this "association with focus" is not an inherent property of this scalar particle. The…

  5. Hyperkahler metrics on focus-focus fibrations

    NASA Astrophysics Data System (ADS)

    Zhao, Jie

    In this thesis, we focus on the study of hyperkahler metric in four dimensional cases, and practice GMN's construction of hyperkahler metric on focus-focus fibrations. We explicitly compute the action-angle coordinates on the local model of focus-focus fibration, and show its semi-global invariant should be harmonic to admit a compatible holomorphic 2-form. Then we study the canonical semi-flat metric on it. After the instanton correction inspired by physics, we get a family of the generalized Ooguri-Vafa metric on focus-focus fibrations, which becomes more local examples of explicit hyperkahler metric in four dimensional cases. In addition, we also make some exploration of the Ooguri-Vafa metric in the thesis. We study the potential function of the Ooguri-Vafa metric, and prove that its nodal set is a cylinder of bounded radius 1 < R < 1. As a result, we get that only on a finite neighborhood of the singular fibre the Ooguri-Vafa metric is a hyperkahler metric. Finally, we give some estimates for the diameter of the fibration under the Oogui-Vafa metric, which confirms that the Oogui-Vafa metric is not complete. The new family of metric constructed in the thesis, we think, will provide more examples to further study of Lagrangian fibrations and mirror symmetry in future.

  6. Use of stationary focused ultrasound fields for characterization of tissue and localized tissue ablation

    NASA Astrophysics Data System (ADS)

    Winey, Brian Andrew

    Ultrasound-induced blood stasis has been observed for more than 30 years. The physical understanding of the phenomenon has not been fully explored. Analytical descriptions of the acoustic interaction with spheres in suspension have been derived but the physical implications and limitations have not been demonstrated. The analytical expressions will be tested against physical observations using numerical simulations. The simulations will begin with stationary spheres and continue with the inclusion of moving spheres and a moving suspending fluid. To date, experimental observations of acoustically induced blood stasis have been either in vitro or invasive. We demonstrate ultrasound-induced blood stasis in murine normal leg muscle versus tumor-bearing legs, observed through noninvasive measurements of optical spectroscopy, and discuss possible diagnostic uses for this effect of ultrasound. We derive the optimal optical wavelengths for measuring the effects of the ultrasound at small source detector separations. Using optical oximetry performed at the optimal wavelengths, we demonstrate that effects of ultrasound can be used to differentiate tumor from normal leg muscle tissue in mice. To provide a statistical analysis of the experiments, we propose a novel diagnostic algorithm that quantitatively differentiates tumor from nontumor with maximum specificity 0.83, maximum sensitivity 0.79, and area under receiver-operating-characteristics curve 0.90. Ultrasound has long been known to cause tissue heating when applied in high intensities. More recently, interest has arisen in the area of High Intensity Focused Ultrasound (HIFU) for localized tissue heating effects, specifically thermal ablation. All present techniques employ focused traveling high intensity acoustic waves to create a region of elevated temperature. Such high intensity traveling waves can be damaging to normal tissue in the vicinity of the focal region, and have demonstrated surface burns and caused

  7. Acoustic characterization of high intensity focused ultrasound fields: A combined measurement and modeling approach

    PubMed Central

    Canney, Michael S.; Bailey, Michael R.; Crum, Lawrence A.; Khokhlova, Vera A.; Sapozhnikov, Oleg A.

    2008-01-01

    Acoustic characterization of high intensity focused ultrasound (HIFU) fields is important both for the accurate prediction of ultrasound induced bioeffects in tissues and for the development of regulatory standards for clinical HIFU devices. In this paper, a method to determine HIFU field parameters at and around the focus is proposed. Nonlinear pressure waveforms were measured and modeled in water and in a tissue-mimicking gel phantom for a 2 MHz transducer with an aperture and focal length of 4.4 cm. Measurements were performed with a fiber optic probe hydrophone at intensity levels up to 24 000 W∕cm2. The inputs to a Khokhlov–Zabolotskaya–Kuznetsov-type numerical model were determined based on experimental low amplitude beam plots. Strongly asymmetric waveforms with peak positive pressures up to 80 MPa and peak negative pressures up to 15 MPa were obtained both numerically and experimentally. Numerical simulations and experimental measurements agreed well; however, when steep shocks were present in the waveform at focal intensity levels higher than 6000 W∕cm2, lower values of the peak positive pressure were observed in the measured waveforms. This underrepresentation was attributed mainly to the limited hydrophone bandwidth of 100 MHz. It is shown that a combination of measurements and modeling is necessary to enable accurate characterization of HIFU fields. PMID:19062878

  8. Focus Intonation in Bengali

    ERIC Educational Resources Information Center

    Hasan, Md. Kamrul

    2015-01-01

    This work attempts to investigate the role of prosody in the syntax of focus in Bangla. The aim of this study is to show the intonation pattern of Bangla in emphasis and focus. In order to do that, the author has looked at the pattern of focus without-i/o as well as with the same. Do they really pose any different focus intonation pattern from…

  9. Alternating phase focused linacs

    DOEpatents

    Swenson, Donald A.

    1980-01-01

    A heavy particle linear accelerator employing rf fields for transverse and ongitudinal focusing as well as acceleration. Drift tube length and gap positions in a standing wave drift tube loaded structure are arranged so that particles are subject to acceleration and succession of focusing and defocusing forces which contain the beam without additional magnetic or electric focusing fields.

  10. High intensity focused ultrasound technology, its scope and applications in therapy and drug delivery.

    PubMed

    Phenix, Christopher Peter; Togtema, Melissa; Pichardo, Samuel; Zehbe, Ingeborg; Curiel, Laura

    2014-01-01

    Ultrasonography is a safe, inexpensive and wide-spread diagnostic tool capable of producing real-time non-invasive images without significant biological effects. However, the propagation of higher energy, intensity and frequency ultrasound waves through living tissues can induce thermal, mechanical and chemical effects useful for a variety of therapeutic applications. With the recent development of clinically approved High Intensity Focused Ultrasound (HIFU) systems, therapeutic ultrasound is now a medical reality. Indeed, HIFU has been used for the thermal ablation of pathological lesions; localized, minimally invasive ultrasound-mediated drug delivery through the transient formation of pores on cell membranes; the temporary disruption of skin and the blood brain barrier; the ultrasound induced break-down of blood clots; and the targeted release of drugs using ultrasound and temperature sensitive drug carriers. This review seeks to engage the pharmaceutical research community by providing an overview on the biological effects of ultrasound as well as highlighting important therapeutic applications, current deficiencies and future directions.

  11. Exploratory Focus Monitoring Test

    NASA Astrophysics Data System (ADS)

    Jedrzejewski, Robert

    1996-07-01

    Determination of the focus of the FOC is difficult because of the lack of aberrations. For small focus errors, it is very difficult to determine the sign of any focus error. We propose to use the field dependent astigmatism to remove this degeneracy. We will perform a fine focus sweep by moving the DOB to -1mm, -0.5mm, 0.0, +0.5mm, +1mm from nominal, and take images of a star using the F486N filter and placing the star in newly-defined apertures that are close to the edges of the field, where the field-dependent astigmatism is greatest. The appearance of the star as a function of focus will be unique, and this will allow an unambiguous determination of the focus. Before this program can be run, new apertures must be defined with size 256x256, SAMPOFF=0 and SAMPOFF=768, and LINEOFF=384.

  12. BrightFocus Foundation

    MedlinePlus

    ... Alzheimer’s Disease Research Program Macular Degeneration Research Program National Glaucoma Research Program Molecular Neurodegeneration ... Foundation BrightFocus Foundation 22512 Gateway Center Drive Clarksburg, MD ...

  13. MAMA Spectroscopic Sensitivity and Focus Monitor

    NASA Astrophysics Data System (ADS)

    Lennon, Daniel

    2009-07-01

    Monitor sensitivity of each MAMA grating mode to detect any change due tocontamination or other causes. Also monitor the STIS focus in a spectroscopic and animaging mode.Whenever possible, obtain parallel airglow spectra with COS.

  14. Focus, 2000-2001.

    ERIC Educational Resources Information Center

    Focus, 2001

    2001-01-01

    These three issues of 2000-2001 "Focus" present a collection of papers focusing on issues related to poverty. The first issue discusses child support enforcement policy and low-income families, highlighting such issues as fragile families and child wellbeing; low-income families and the child support enforcement system; child support enforcement…

  15. FOCUS: Sustainable Mathematics Successes

    ERIC Educational Resources Information Center

    Mireles, Selina V.; Acee, Taylor W.; Gerber, Lindsey N.

    2014-01-01

    The FOCUS (Fundamentals of Conceptual Understanding and Success) Co-Requisite Model Intervention (FOCUS Intervention) for College Algebra was developed as part of the Developmental Education Demonstration Projects (DEDP) in Texas. The program was designed to use multiple services, courses, and best practices to support student completion of a…

  16. Agreement, Shells, and Focus.

    ERIC Educational Resources Information Center

    Simpson, Andrew; Wu, Zoe

    2002-01-01

    Reconsiders development and licensing of agreement as a syntactic projection and argues for a productive developmental relation between agreement and the category of focus. Suggests that focus projections are initially selected by a variety of functional heads with real semantic content, then, over time decays into a simple concord shell. Upon…

  17. Microfabricated particle focusing device

    DOEpatents

    Ravula, Surendra K.; Arrington, Christian L.; Sigman, Jennifer K.; Branch, Darren W.; Brener, Igal; Clem, Paul G.; James, Conrad D.; Hill, Martyn; Boltryk, Rosemary June

    2013-04-23

    A microfabricated particle focusing device comprises an acoustic portion to preconcentrate particles over large spatial dimensions into particle streams and a dielectrophoretic portion for finer particle focusing into single-file columns. The device can be used for high throughput assays for which it is necessary to isolate and investigate small bundles of particles and single particles.

  18. Absorption driven focus shift

    NASA Astrophysics Data System (ADS)

    Harrop, N.; Wolf, S.; Maerten, O.; Dudek, K.; Ballach, S.; Kramer, R.

    2016-03-01

    Modern high brilliance near infrared lasers have seen a tremendous growth in applications throughout the world. Increased productivity has been achieved by higher laser power and increased brilliance of lasers. Positive impacts on the performance and costs of parts are opposed to threats on process stability and quality, namely shift of focus position over time. A high initial process quality will be reduced by contamination of optics, eventually leading to a focus shift or even destruction of the optics. Focus analysis at full power of multi-kilowatt high brilliance lasers is a very demanding task because of high power densities in the spot and the high power load on optical elements. With the newly developed high power projection optics, the High-Power Micro-Spot Monitor High Brilliance (HP-MSM-HB) is able to measure focus diameter as low as 20 μm at power levels up to 10 kW at very low internal focus shift. A main driving factor behind thermally induced focus shift is the absorption level of the optical element. A newly developed measuring system is designed to determine the relative absorption level in reference to a gold standard. Test results presented show a direct correlation between absorption levels and focus shift. The ability to determine the absorption level of optical elements as well as their performance at full processing power before they are put to use, enables a high level of quality assurance for optics manufacturers and processing head manufacturers alike.

  19. Focused ultrasound in ophthalmology

    PubMed Central

    Silverman, Ronald H

    2016-01-01

    The use of focused ultrasound to obtain diagnostically significant information about the eye goes back to the 1950s. This review describes the historical and technological development of ophthalmic ultrasound and its clinical application and impact. Ultrasound, like light, can be focused, which is crucial for formation of high-resolution, diagnostically useful images. Focused, single-element, mechanically scanned transducers are most common in ophthalmology. Specially designed transducers have been used to generate focused, high-intensity ultrasound that through thermal effects has been used to treat glaucoma (via ciliodestruction), tumors, and other pathologies. Linear and annular transducer arrays offer synthetic focusing in which precise timing of the excitation of independently addressable array elements allows formation of a converging wavefront to create a focus at one or more programmable depths. Most recently, linear array-based plane-wave ultrasound, in which the array emits an unfocused wavefront and focusing is performed solely on received data, has been demonstrated for imaging ocular anatomy and blood flow. While the history of ophthalmic ultrasound extends back over half-a-century, new and powerful technologic advances continue to be made, offering the prospect of novel diagnostic capabilities. PMID:27757007

  20. Flat Focusing Mirror

    PubMed Central

    Cheng, Y. C.; Kicas, S.; Trull, J.; Peckus, M.; Cojocaru, C.; Vilaseca, R.; Drazdys, R.; Staliunas, K.

    2014-01-01

    The control of spatial propagation properties of narrow light beams such as divergence, focusing or imaging are main objectives in optics and photonics. In this letter, we propose and demonstrate experimentally a flat focusing mirror, based on an especially designed dielectric structure without any optical axis. More generally, it also enables imaging any light pattern in reflection. The flat focusing mirror with a transversal invariance can largely increase the applicability of structured photonic materials for light beam propagation control in small-dimension photonic circuits. PMID:25228358

  1. Final focus nomenclature

    SciTech Connect

    Erickson, R.

    1986-08-08

    The formal names and common names for all devices in the final focus system of the SLC are listed. The formal names consist of a device type designator, microprocessor designator, and a four-digit unit number. (LEW)

  2. Focusing corner cube

    DOEpatents

    Monjes, J.A.

    1985-09-12

    This invention retortreflects and focuses a beam of light. The invention comprises a modified corner cube reflector wherein one reflective surface is planar, a second reflective surface is spherical, and the third reflective surface may be planar or convex cylindrical.

  3. Passive focus sensor

    NASA Astrophysics Data System (ADS)

    Engelhardt, Kai; Knop, Karl

    1995-05-01

    A focus-sensor module that could take the place of the visual-image control for professional large-format cameras was fabricated. In addition, a passive focus-sensing method was shown to work at arbitrary locations and orientations in the recording plane of large-format professional cameras. A focus resolution of better than 0.1 mm and a range of measurement of +/- 5 mm at the image side were obtained at a minimum level of illuminance and with an aperture f/5.6 of the imaging lens. In the current method, three out of four images that arose from various sections of the camera's objective lens were applied for triangulation. The demonstrated approach was based on a linear photodiode array and employed one-dimensional image information for focus sensing.

  4. Inertial Focusing in Microfluidics

    PubMed Central

    Martel, Joseph M.; Toner, Mehmet

    2015-01-01

    When Segré and Silberberg in 1961 witnessed particles in a laminar pipe flow congregating at an annulus in the pipe, scientists were perplexed and spent decades learning why such behavior occurred, finally understanding that it was caused by previously unknown forces on particles in an inertial flow. The advent of microfluidics opened a new realm of possibilities for inertial focusing in the processing of biological fluids and cellular suspensions and created a field that is now rapidly expanding. Over the past five years, inertial focusing has enabled high-throughput, simple, and precise manipulation of bodily fluids for a myriad of applications in point-of-care and clinical diagnostics. This review describes the theoretical developments that have made the field of inertial focusing what it is today and presents the key applications that will make inertial focusing a mainstream technology in the future. PMID:24905880

  5. Facility Focus: Food Service.

    ERIC Educational Resources Information Center

    College Planning & Management, 2002

    2002-01-01

    Describes the Hawthorn Court Community Center at Iowa State University, Ames, and the HUB-Robeson Center at Pennsylvania State University. Focuses on the food service offered in these new student-life buildings. Includes photographs. (EV)

  6. Final focus test beam

    SciTech Connect

    Not Available

    1991-03-01

    This report discusses the following: the Final Focus Test Beam Project; optical design; magnets; instrumentation; magnetic measurement and BPM calibration; mechanical alignment and stabilization; vacuum system; power supplies; control system; radiation shielding and personnel protection; infrastructure; and administration.

  7. High harmonics focusing undulator

    SciTech Connect

    Varfolomeev, A.A.; Hairetdinov, A.H.; Smirnov, A.V.; Khlebnikov, A.S.

    1995-12-31

    It was shown in our previous work that there exist a possibility to enhance significantly the {open_quote}natural{close_quote} focusing properties of the hybrid undulator. Here we analyze the actual undulator configurations which could provide such field structure. Numerical simulations using 2D code PANDIRA were carried out and the enhanced focusing properties of the undulator were demonstrated. The obtained results provide the solution for the beam transport in a very long (short wavelength) undulator schemes.

  8. Electron beam focusing system

    SciTech Connect

    Dikansky, N.; Nagaitsev, S.; Parkhomchuk, V.

    1997-09-01

    The high energy electron cooling requires a very cold electron beam. Thus, the electron beam focusing system is very important for the performance of electron cooling. A system with and without longitudinal magnetic field is presented for discussion. Interaction of electron beam with the vacuum chamber as well as with the background ions and stored antiprotons can cause the coherent electron beam instabilities. Focusing system requirements needed to suppress these instabilities are presented.

  9. Focusing the parabolic antenna

    NASA Technical Reports Server (NTRS)

    Wu, L. K.; Moore, R. K.; Ulaby, F. T.

    1983-01-01

    The focused parabolic antenna has far field pattern characteristics in the radiating near field region. Therefore, it can provide fine resolutions in the across range dimensions. The technique of focusing the parabolic antenna is discussed and applied to a 2-1/2 foot parabolic antenna at X-band. The results of the pattern measurements at various ranges from 2.8 m to 5 m are provided.

  10. Plutonium focus area

    SciTech Connect

    1996-08-01

    To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this new approach, EM developed a management structure and principles that led to the creation of specific Focus Areas. These organizations were designed to focus the scientific and technical talent throughout DOE and the national scientific community on the major environmental restoration and waste management problems facing DOE. The Focus Area approach provides the framework for intersite cooperation and leveraging of resources on common problems. After the original establishment of five major Focus Areas within the Office of Technology Development (EM-50, now called the Office of Science and Technology), the Nuclear Materials Stabilization Task Group (EM-66) followed the structure already in place in EM-50 and chartered the Plutonium Focus Area (PFA). The following information outlines the scope and mission of the EM, EM-60, and EM-66 organizations as related to the PFA organizational structure.

  11. New molecular identifiers for Simulium limbatum and Simulium incrustatum s.l. and the detection of genetic substructure with potential implications for onchocerciasis epidemiology in the Amazonia focus of Brazil.

    PubMed

    Conceição, Priscila A; Crainey, James L; Almeida, Tatiana P; Shelley, Anthony J; Luz, Sergio L B

    2013-08-01

    The Amazonia onchocerciasis focus of southern Venezuela and northern Brazil is the larger of the two remaining Latin American onchocerciasis foci where disease transmission still occurs and is often regarded as the most challenging of all the Latin American foci to eliminate onchocerciasis. The site is home to a population of over 20,000 semi-nomadic, hunter-gatherer Yanomami people and is made-up of a mosaic of rainforest and savannah ecologies, which are influenced by the area's undulating terrain and rich geological diversity. At least six blackfly vectors have been implicated in onchocerciasis transmission in this focus; however, because of the difficulty in their routine identification the relative importance of each has been obscured. Simulium limbatum and Simulium incrustatum s.l. have both been recorded as vectors in the Amazonia focus, but they are difficult to discriminate morphologically and thus the ecological range of these species, and indeed the presence of S. limbatum in the Amazonia focus at all, have remained controversial. In the work described here, we report 15 S. incrustatum s.l. CO1 sequences and 27 S. limbatum sequences obtained from field-caught adult female blackflies collected from forest and savannah localities, inside and just outside the Amazonia focus. Phylogenetic analysis with the sequences generated in this study, showed that both the S. limbatum and the S. incrustatum s.l. CO1 sequences obtained (even from specimens living in sympatry) all fell into discrete species-specific bootstrap-supported monophyletic groups and thus confirmed the utility of the CO1 gene for identifying both these species inside the Amazonia focus. As the S. limbatum-exclusive cluster included CO1 sequences obtained from forest-caught and morphologically identified specimens these results provide the clearest evidence yet of the presence of S. limbatum inside the Amazonia focus. The question, however, of whether S. limbatum is actually a vector in the focus

  12. New molecular identifiers for Simulium limbatum and Simulium incrustatum s.l. and the detection of genetic substructure with potential implications for onchocerciasis epidemiology in the Amazonia focus of Brazil.

    PubMed

    Conceição, Priscila A; Crainey, James L; Almeida, Tatiana P; Shelley, Anthony J; Luz, Sergio L B

    2013-08-01

    The Amazonia onchocerciasis focus of southern Venezuela and northern Brazil is the larger of the two remaining Latin American onchocerciasis foci where disease transmission still occurs and is often regarded as the most challenging of all the Latin American foci to eliminate onchocerciasis. The site is home to a population of over 20,000 semi-nomadic, hunter-gatherer Yanomami people and is made-up of a mosaic of rainforest and savannah ecologies, which are influenced by the area's undulating terrain and rich geological diversity. At least six blackfly vectors have been implicated in onchocerciasis transmission in this focus; however, because of the difficulty in their routine identification the relative importance of each has been obscured. Simulium limbatum and Simulium incrustatum s.l. have both been recorded as vectors in the Amazonia focus, but they are difficult to discriminate morphologically and thus the ecological range of these species, and indeed the presence of S. limbatum in the Amazonia focus at all, have remained controversial. In the work described here, we report 15 S. incrustatum s.l. CO1 sequences and 27 S. limbatum sequences obtained from field-caught adult female blackflies collected from forest and savannah localities, inside and just outside the Amazonia focus. Phylogenetic analysis with the sequences generated in this study, showed that both the S. limbatum and the S. incrustatum s.l. CO1 sequences obtained (even from specimens living in sympatry) all fell into discrete species-specific bootstrap-supported monophyletic groups and thus confirmed the utility of the CO1 gene for identifying both these species inside the Amazonia focus. As the S. limbatum-exclusive cluster included CO1 sequences obtained from forest-caught and morphologically identified specimens these results provide the clearest evidence yet of the presence of S. limbatum inside the Amazonia focus. The question, however, of whether S. limbatum is actually a vector in the focus

  13. EDITORIAL: Focus on Plasmonics FOCUS ON PLASMONICS

    NASA Astrophysics Data System (ADS)

    Bozhevolnyi, Sergey; García-Vidal, Francisco

    2008-10-01

    Plasmonics is an emerging field in optics dealing with the so-called surface plasmons whose extraordinary properties are being both analyzed from a fundamental point of view and exploited for numerous technological applications. Surface plasmons associated with surface electron density oscillations decorating metal-dielectric interfaces were discovered by Rufus Ritchie in the 1950s. Since the seventies, the subwavelength confinement of electromagnetic fields as well as their enhancement inherent to the surface plasmon excitation has been widely used for spectroscopic purposes. Recent advances in nano-fabrication, characterization and modelling techniques have allowed unique properties of these surface electromagnetic modes to be explored with respect to subwavelength field localization and waveguiding, opening the path to truly nanoscale plasmonic optical devices. This area of investigation also has interesting links with research on photonic band gap materials and the field of optical metamaterials. Nowadays, plasmonics can be seen as a mature interdisciplinary area of research in which scientists coming from different backgrounds (chemistry, physics, optics and engineering) strive to discover and exploit new and exciting phenomena associated with surface plasmons. The already made and forthcoming discoveries will have impacts in many fields of science and technology, including not only photonics and materials science but also computation, biology and medicine, among others. This focus issue of New Journal of Physics is intended to cover all the aforementioned capabilities of surface plasmons by presenting a current overview of state-of-the-art advances achieved by the leading groups in this field of research. The below list of articles represents the first contributions to the collection and further additions will appear soon. Focus on Plasmonics Contents Nanoantenna array-induced fluorescence enhancement and reduced lifetimes Reuben M Bakker, Vladimir P Drachev

  14. Fast focus field calculations

    NASA Astrophysics Data System (ADS)

    Leutenegger, Marcel; Geissbuehler, Matthias; Märki, Iwan; Leitgeb, Rainer A.; Lasser, Theo

    2008-02-01

    We present a method for fast calculation of the electromagnetic field near the focus of an objective with a high numerical aperture (NA). Instead of direct integration, the vectorial Debye diffraction integral is evaluated with the fast Fourier transform for calculating the electromagnetic field in the entire focal region. We generalize this concept with the chirp z transform for obtaining a flexible sampling grid and an additional gain in computation speed. Under the conditions for the validity of the Debye integral representation, our method yields the amplitude, phase and polarization of the focus field for an arbitrary paraxial input field in the aperture of the objective. Our fast calculation method is particularly useful for engineering the point-spread function or for fast image deconvolution. We present several case studies by calculating the focus fields of high NA oil immersion objectives for various amplitude, polarization and phase distributions of the input field. In addition, the calculation of an extended polychromatic focus field generated by a Bessel beam is presented. This extended focus field is of particular interest for Fourier domain optical coherence tomography because it preserves a lateral resolution of a few micrometers over an axial distance in the millimeter range.

  15. NICMOS focus monitor

    NASA Astrophysics Data System (ADS)

    Schneider, Glenn

    1997-07-01

    This proposal is used to determine and monitor the optimal focus and tilt settings for all three NICMOS cameras. It is derived from SM2/NIC 7041, but is structurally quite a bit different. This proposal is built to run NIC1/2 focus sweeps on a weekly basis, and NIC3 focus sweeps twice a week during SMOV {following the "interim" runs of the 7150}. 7043 will run for as long as it is deemed necessary to keep track of the camera focii and to monitor the dewar anomaly. After the discussion on 20/3/96, this proposal is written to run 4 complete 1-week iterations starting 3 days after the last run of the 7150 {NICMOS COARSE OPTICAL ALIGNMENT, PART 2}.

  16. Decontamination & decommissioning focus area

    SciTech Connect

    1996-08-01

    In January 1994, the US Department of Energy Office of Environmental Management (DOE EM) formally introduced its new approach to managing DOE`s environmental research and technology development activities. The goal of the new approach is to conduct research and development in critical areas of interest to DOE, utilizing the best talent in the Department and in the national science community. To facilitate this solutions-oriented approach, the Office of Science and Technology (EM-50, formerly the Office of Technology Development) formed five Focus AReas to stimulate the required basic research, development, and demonstration efforts to seek new, innovative cleanup methods. In February 1995, EM-50 selected the DOE Morgantown Energy Technology Center (METC) to lead implementation of one of these Focus Areas: the Decontamination and Decommissioning (D & D) Focus Area.

  17. Sagittal focusing Laue monochromator

    DOEpatents

    Zhong; Zhong , Hanson; Jonathan , Hastings; Jerome , Kao; Chi-Chang , Lenhard; Anthony , Siddons; David Peter , Zhong; Hui

    2009-03-24

    An x-ray focusing device generally includes a slide pivotable about a pivot point defined at a forward end thereof, a rail unit fixed with respect to the pivotable slide, a forward crystal for focusing x-rays disposed at the forward end of the pivotable slide and a rearward crystal for focusing x-rays movably coupled to the pivotable slide and the fixed rail unit at a distance rearward from the forward crystal. The forward and rearward crystals define reciprocal angles of incidence with respect to the pivot point, wherein pivoting of the slide about the pivot point changes the incidence angles of the forward and rearward crystals while simultaneously changing the distance between the forward and rearward crystals.

  18. Focusing on Mathematical Arguments

    ERIC Educational Resources Information Center

    Singletary, Laura M.; Conner, AnnaMarie

    2015-01-01

    "Collective argumentation" occurs when a group works together to arrive at a conclusion (supporting it with evidence). Simplistically, this occurs when students give answers to questions and tell how they arrived at the answer, perhaps prompted by a teacher. But collective argumentation can be much richer, with a focus on the process of…

  19. Youth Leadership. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1995

    1995-01-01

    This theme issue focuses on motivating young people to learn by providing leadership opportunities in school. "Coca-Cola Valued Youth Program: Assessing Progress" (Josie Danini Supik) examines the program's success. This program, which trains high-risk middle and high school students as tutors of younger children, has dramatically lowered dropout…

  20. Adolescent Literacy. Focus On

    ERIC Educational Resources Information Center

    Molineaux, Rebecca

    2009-01-01

    Evidence suggests that there is a crisis in adolescent literacy. Part of the problem is that students often receive little literacy instruction after elementary school. This "Focus On" examines the literacy instruction that adolescents need to be successful as they move on to more challenging texts in middle and high school. In addition, this…

  1. Focus on the President.

    ERIC Educational Resources Information Center

    Optometric Education, 2000

    2000-01-01

    An interview with the new president of the Association of Schools and Colleges of Optometry, John Schoessler, considers issues the president wishes to focus on during his presidency, changes in optometry students over the years, people who influenced his educational ideas, and research currently being conducted at Ohio State University College of…

  2. Focus on the President.

    ERIC Educational Resources Information Center

    Optometric Education, 1996

    1996-01-01

    In an interview, the incoming president of the Association of Schools and Colleges of Optometry (ASCO), Thomas L. Lewis, discusses his goals for the association, the challenges facing optometric education in the next decade, cooperation between ASCO and other professional organizations in optometry, his mentors in the profession, his focus as a…

  3. Focus on Basics, 1997.

    ERIC Educational Resources Information Center

    Focus on Basics, 1997

    1997-01-01

    Together, these four newsletters contain 36 articles devoted to adult literacy research and practice and the relationship between them. The following articles are included: "A Productive Partnership" (Richard J. Murnane, Bob Bickerton); "Welcome to 'Focus on Basics'" (Barbara Garner); "Applying Research on the Last Frontier" (Karen Backlund, Kathy…

  4. Focusing on the Invisible

    ERIC Educational Resources Information Center

    Haley, Tim R.

    2008-01-01

    This article seeks to answer the question of whether or not the design and development of an educational laboratory really changes when the focus is on nanotechnology. It explores current laboratory building trends and the added considerations for building a nanotechnology laboratory. The author leaves the reader with additional points to consider…

  5. Education Policy. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1998

    1998-01-01

    This theme issue includes five articles that focus on educational policy in the Texas legislature in relation to student retention, Internet access, and sexual harassment. "1999 Texas Legislative Session--End of an Era?" (Albert Cortez, Maria Robledo Montecel) examines educational equity issues facing legislators: school funding, including the…

  6. Focusing educational initiatives

    NASA Technical Reports Server (NTRS)

    Parks, George K.

    1990-01-01

    The United States will soon be facing a critical shortage of aerospace scientists and engineers. To address this problem, Space Grant Colleges can assist in focusing interest in existing educational initiatives and in creating new educational opportunities, particularly for women and underrepresented minorities.

  7. Focus on stochastic thermodynamics

    NASA Astrophysics Data System (ADS)

    Van den Broeck, Christian; Sasa, Shin-ichi; Seifert, Udo

    2016-02-01

    We introduce the thirty papers collected in this ‘focus on’ issue. The contributions explore conceptual issues within and around stochastic thermodynamics, use this framework for the theoretical modeling and experimental investigation of specific systems, and provide further perspectives on and for this active field.

  8. Focus on Bilingual Education.

    ERIC Educational Resources Information Center

    Mayo, Donald S., Ed.

    1982-01-01

    This collection of essays focuses on issues in bilingual education. First, Elizabeth Flynn examines different kinds of bilingual programs; efforts made towards cultural pluralism in a number of countries; national benefits to be derived from bilingualism; the needs of American ethnic groups, new immigrants, and foreign students; and the pros and…

  9. Instructional Technology. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1997

    1997-01-01

    This theme issue includes five articles that focus on implementing instructional technology in ways that benefit all students, including limited-English-proficient, minority, economically disadvantaged, and at-risk students. "Cruising the Web with English Language Learners" (Laura Chris Green) presents three scenarios using the World Wide Web in…

  10. Theme: Focus on Teaching.

    ERIC Educational Resources Information Center

    Connors, James J.; And Others

    1996-01-01

    Includes "The More Things Change..." (Connors); "Students--Bored of Education?" (Earle); "Yesterday, Today and Tomorrow" (Wesch et al.); "Attitude and the Value of Environment" (Foster); "Fins, Feathers and Fur" (Crank); "Greenhouse as a Focus for Agriscience" (Hurst); and "Agricultural and Environmental Education at Milton Hershey School"…

  11. Focus on the Presidency.

    ERIC Educational Resources Information Center

    Lindroth, Linda K.

    1996-01-01

    Uses Presidential and House of Representatives elections as basis for year-long curriculum focus on civics education, integrating print material, software, and the Internet. Describes classroom activities, Internet sites, and software described for four major areas: (1) campaigning for office; (2) moving into a new home; (3) reporting for work;…

  12. Equity. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1998

    1998-01-01

    This theme issue focuses on equity in children's literature, public funding for private schools, women in educational fields, female dropouts, and the relationship between school violence and family and community violence. "Violence in Our Schools" (Bradley Scott) explores reasons for school violence (media violence, isolation from family, racial…

  13. Bilingual Education. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1998

    1998-01-01

    This theme issue focuses on instructional practices, evaluation, and the state of bilingual education. "Effective Implementation of Bilingual Programs: Reflections from the Field" (Abelardo Villarreal, Adela Solis) describes the key characteristics of successful bilingual programs: vision and goals; program leadership; linkage to central office…

  14. Public Engagement. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1996

    1996-01-01

    This newsletter includes six articles that examine key issues facing public schools and communities related to accountability, bilingual education, immigrant education, school finance, and school choice. In addressing these issues, articles focus on the importance of community involvement and input in local school reform efforts aimed at achieving…

  15. Focus on First Graders.

    ERIC Educational Resources Information Center

    Schwartz, Shari S.

    The result of a collaboration between the El Paso, Texas, school district and community agencies, the Focus on First Graders program provides early intervention and prevention using a comprehensive approach to providing a variety of services at the school to at-risk first graders from low income families. Teachers and parents were surveyed to…

  16. Policy Update. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1995

    1995-01-01

    This theme issue focuses on the drastic revision of the Texas education code undertaken during the 1995 state legislative session. "Education Policy Reform: Key Points for Districts" (Albert Cortez, Mikki Symonds) outlines critical issues in the legislation that have an impact on educational quality: charter schools exempt from state regulations;…

  17. Young Children. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1998

    1998-01-01

    This theme issue includes five articles that focus on educational, cognitive, and brain research with implications for early childhood educators, including those who work with limited-English-proficient, minority, and economically disadvantaged children. "Coming to Grips with Reading Instruction at the Early Grades" (Christie L. Goodman) reports…

  18. Focus on Efficient Management.

    ERIC Educational Resources Information Center

    Kentucky State Dept. of Education, Frankfort. Office of Resource Management.

    Compiled as a workshop handbook, this guide presents information to help food service program administrators comply with federal regulations and evaluate and upgrade their operations. Part I discusses requirements of the National School Lunch Program, focusing on the "offer versus serve" method of service enacted in 1976 to reduce waste. After an…

  19. Homework. Focus On

    ERIC Educational Resources Information Center

    Rahal, Michelle Layer

    2010-01-01

    Homework has been an integral part of the educational system for over 100 years. What likely began as simple memorization tasks has evolved into complex projects and sparked an increasingly heated debate over the purpose and value of homework assignments. This "Focus On" examines the purpose of homework, how to create homework that has value,…

  20. Focused on Student Success

    ERIC Educational Resources Information Center

    California Community Colleges, Chancellor's Office, 2014

    2014-01-01

    In January 2011, the California Community Colleges Board of Governors formed a task force to chart a roadmap for system-wide focus on student success. The task force identified best practices and designed evidence-based recommendations to ensure student success is a driving theme in colleges. This comprehensive plan, known as the Student Success…

  1. [Focus: Family Communication].

    ERIC Educational Resources Information Center

    Barnes, Richard E., Ed.

    1977-01-01

    This issue of the "Journal of the Wisconsin Communication Association" focuses on family communication and contains the following articles: "Marital Typologies: An Alternative Approach to the Study of Communication in Enduring Relations" by Mary Anne Fitzpatrick, "Intimate Communication and the Family" by Marilyn D. LaCourt, and "A Study in…

  2. School Reform. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1998

    1998-01-01

    This theme issue addresses school reform, focusing on accountability, attrition, public-supported private education, equitable education, and schoolwide reform. "School-Student Performance and Accountability" (Jose A. Cardenas) discusses what constitutes good performance in school; the shifting emphasis among the input, output, and process of…

  3. Focus on Rashomon.

    ERIC Educational Resources Information Center

    Richie, Donald S., Ed.

    This Film Focus series is a collection of reviews, essays, and commentaries on the Japanese film Rashomon. The plot consists of an attack, a rape, and a robbery, all of which probably occurred during the Middle Ages. Each character relates his own version of what happened, or might have happened, revealing the outward and inner driving forces,…

  4. Focus: DNA probes

    SciTech Connect

    Not Available

    1986-11-01

    Progress in the development of DNA probes for the identification and quantitation of specific genetic sequences in biological samples is reviewed. Current research efforts in the development of DNA probes for the diagnosis of a wide variety of bacterial, viral, and other infectious diseases, such as herpes simplex and cytomegalovirus, and inherited genetic diseases such as cystic fibrosis and sickle cell anemia are discussed. Progress in development of DNA probe assays for cancer diagnosis, detection of Salmonella food poisoning, tissue typing (detection of histocompatibility antigens), mutagen screening, and animal diseases, among other applications is included.

  5. Focused ion beam system

    DOEpatents

    Leung, Ka-Ngo; Gough, Richard A.; Ji, Qing; Lee, Yung-Hee Yvette

    1999-01-01

    A focused ion beam (FIB) system produces a final beam spot size down to 0.1 .mu.m or less and an ion beam output current on the order of microamps. The FIB system increases ion source brightness by properly configuring the first (plasma) and second (extraction) electrodes. The first electrode is configured to have a high aperture diameter to electrode thickness aspect ratio. Additional accelerator and focusing electrodes are used to produce the final beam. As few as five electrodes can be used, providing a very compact FIB system with a length down to only 20 mm. Multibeamlet arrangements with a single ion source can be produced to increase throughput. The FIB system can be used for nanolithography and doping applications for fabrication of semiconductor devices with minimum feature sizes of 0.1 .mu.m or less.

  6. Focused ion beam system

    DOEpatents

    Leung, K.; Gough, R.A.; Ji, Q.; Lee, Y.Y.

    1999-08-31

    A focused ion beam (FIB) system produces a final beam spot size down to 0.1 {mu}m or less and an ion beam output current on the order of microamps. The FIB system increases ion source brightness by properly configuring the first (plasma) and second (extraction) electrodes. The first electrode is configured to have a high aperture diameter to electrode thickness aspect ratio. Additional accelerator and focusing electrodes are used to produce the final beam. As few as five electrodes can be used, providing a very compact FIB system with a length down to only 20 mm. Multibeamlet arrangements with a single ion source can be produced to increase throughput. The FIB system can be used for nanolithography and doping applications for fabrication of semiconductor devices with minimum feature sizes of 0.1 m or less. 13 figs.

  7. Focus on quantum efficiency

    NASA Astrophysics Data System (ADS)

    Buchleitner, Andreas; Burghardt, Irene; Cheng, Yuan-Chung; Scholes, Gregory D.; Schwarz, Ulrich T.; Weber-Bargioni, Alexander; Wellens, Thomas

    2014-10-01

    Technologies which convert light into energy, and vice versa, rely on complex, microscopic transport processes in the condensed phase, which obey the laws of quantum mechanics, but hitherto lack systematic analysis and modeling. Given our much improved understanding of multicomponent, disordered, highly structured, open quantum systems, this ‘focus on’ collection collects cutting-edge research on theoretical and experimental aspects of quantum transport in truly complex systems as defined, e.g., by the macromolecular functional complexes at the heart of photosynthesis, by organic quantum wires, or even photovoltaic devices. To what extent microscopic quantum coherence effects can (be made to) impact on macroscopic transport behavior is an equally challenging and controversial question, and this ‘focus on’ collection provides a setting for the present state of affairs, as well as for the ‘quantum opportunities’ on the horizon.

  8. Focused on Robert E

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image, taken by the microscopic imager on the Mars Exploration Rover Opportunity, shows a geological feature dubbed 'Robert E.' Light from the top is illuminating the feature, which is located within the rock outcrop at Meridiani Planum, Mars. Several images, each showing a different part of 'Robert E' in good focus, were merged to produce this view. The area in this image, taken on Sol 15 of the Opportunity mission, is 2.2 centimeters (0.8 inches) across.

  9. Subsurface contaminants focus area

    SciTech Connect

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  10. Transverse field focused system

    DOEpatents

    Anderson, Oscar A.

    1986-01-01

    A transverse field focused (TFF) system for transport or acceleration of an intense sheet beam of negative ions in which a serial arrangement of a plurality of pairs of concentric cylindrical-arc electrodes is provided. Acceleration of the sheet beam can be achieved by progressively increasing the mean electrode voltage of successive electrode pairs. Because the beam is curved by the electrodes, the system can be designed to transport the beam through a maze passage which is baffled to prevent line of sight therethrough. Edge containment of the beam can be achieved by shaping the side edges of the electrodes to produce an electric force vector directed inwardly from the electrode edges.

  11. Focus on 'Rue Legendre'

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Annotated image of PIA04196 Focus on 'Rue Legendre'

    Spirit used its microscopic imager to take this mosaic of the rock 'Haussmann' on martian day, or sol, 563 (August 3, 2005). The specific target is nicknamed 'Rue Legendre.' The rounded nature of the pebbles indicates that they were eroded on the surface before being embedded into the Haussmann rock. The size of the larger of the two pebbles is approximately 3 centimeters (1.2 inches). The rock probably formed from impact ejecta, consistent with other rocks Spirit discovered during its climb to the summit of 'Husband Hill.'

  12. Modeling localized delivery of Doxorubicin to the brain following focused ultrasound enhanced blood-brain barrier permeability

    NASA Astrophysics Data System (ADS)

    Nhan, Tam; Burgess, Alison; Lilge, Lothar; Hynynen, Kullervo

    2014-10-01

    Doxorubicin (Dox) is a well-established chemotherapeutic agent, however it has limited efficacy in treating brain malignancies due to the presence of the blood-brain barrier (BBB). Recent preclinical studies have demonstrated that focused ultrasound induced BBB disruption (BBBD) enables efficient delivery of Dox to the brain. For future treatment planning of BBBD-based drug delivery, it is crucial to establish a mathematical framework to predict the effect of transient BBB permeability enhancement on the spatiotemporal distribution of Dox at the targeted area. The constructed model considers Dox concentrations within three compartments (plasma, extracellular, intracellular) that are governed by various transport processes (e.g. diffusion in interstitial space, exchange across vessel wall, clearance by cerebral spinal fluid, uptake by brain cells). By examining several clinical treatment aspects (e.g. sonication scheme, permeability enhancement, injection mode), our simulation results support the experimental findings of optimal interval delay between two consecutive sonications and therapeutically-sufficient intracellular concentration with respect to transfer constant Ktrans range of 0.01-0.03 min-1. Finally, the model suggests that infusion over a short duration (20-60 min) should be employed along with single-sonication or multiple-sonication at 10 min interval to ensure maximum delivery to the intracellular compartment while attaining minimal cardiotoxicity via suppressing peak plasma concentration.

  13. Isoelectric focusing in space

    NASA Technical Reports Server (NTRS)

    Bier, M.; Egen, N. B.; Mosher, R. A.; Twitty, G. E.

    1982-01-01

    The potential of space electrophoresis is conditioned by the fact that all electrophoretic techniques require the suppression of gravity-caused convection. Isoelectric focusing (IEF) is a powerful variant of electrophoresis, in which amphoteric substances are separated in a pH gradient according to their isoelectric points. A new apparatus for large scale IEF, utilizing a recycling principle, has been developed. In the ground-based prototype, laminar flow is provided by a series of parallel filter elements. The operation of the apparatus is monitored by an automated array of pH and ultraviolet absorption sensors under control of a desk-top computer. The apparatus has proven to be useful for the purification of a variety of enzymes, snake venom proteins, peptide hormones, and other biologicals, including interferon produced by genetic engineering techniques. In planning for a possible space apparatus, a crucial question regarding electroosmosis needs to be addressed To solve this problem, simple focusing test modules are planned for inclusion in an early Shuttle flight.

  14. [Therapies by focused ultrasound].

    PubMed

    Grenier, N; Trillaud, H; Palussière, J; Mougenot, C; Quesson, B; Denis De Senneville, B; Moonen, C

    2007-11-01

    Many techniques of thermotherapy have emerged over the last several years in the field of oncology using different types of physical agents, including ultrasound. Only ultrasound can target deep seated lesions non-invasively without need for percutaneous probe insertion. Depending on their utilization, it is possible to select either thermal effects, in a continuous mode, at low temperature (allowing thermo-induced biological effects) or at high temperature (allowing thermoablation), or mechanical effects, in a pulsed mode, at low energy level (allowing biological effects) or at high energy levels (histotripsy). Thermoablation by focused ultrasound is now developing fast for applications in many organs. It gained a well defined role for the treatment of prostatic cancer and uterine leiomyoma but needs to be better evaluated in other organs such as the breast. Treatment of abdominal tumors must still be considered as experimental as long as problems related to acoustic interfaces (produced by ribs and gas) and movement correction are not resolved. Biological applications of focused ultrasound are currently being explored and have a great long term potential.

  15. Electrostatic Focusing Lens

    NASA Astrophysics Data System (ADS)

    Thomas, Eric; Hopkins, Demitri

    2011-10-01

    We developed an electrostatic focusing lens capable of generating DD reactions, by focusing deuterium ions generated from a pointed emitter at a frozen heavy water target. Due to difficulty with the pointed emitter, we later switched to a hollow cathode design. To model the lenses, chamber, and calculate the dimensions for the design that would maximize ion energy and density, the program SIMION was used. During stable operation, vacuum was hand adjusted around 10-13 mTorr. To keep stable beam, DC voltage generator was varied between 15-25 kV. Hand adjusting was necessary, because at points in the operation the frozen heavy water would release vapor at an increased rate. This caused the pressure to rise and the beam current to spike, creating instabilities and an arc to the lens. Three methods were used to determine successful DD production. (1) Two differently shielded Geiger counters (unshielded and UHMW-PE insulated tube), (2) Spectrophotometer comparing control peaks with heavy water tests, and (3) a calibrated bubble dosimeter specific to neutrons. Analysis of the results suggest the neutrons flux varied from 532 to 1.4 × 106 neutrons/sec, and require further tests to plot and narrow results.

  16. Flux focusing eddy current probe

    NASA Technical Reports Server (NTRS)

    Simpson, John W. (Inventor); Clendenin, C. Gerald (Inventor); Fulton, James P. (Inventor); Wincheski, Russell A. (Inventor); Todhunter, Ronald G. (Inventor); Namkung, Min (Inventor); Nath, Shridhar C. (Inventor)

    1997-01-01

    A flux-focusing electromagnetic sensor which uses a ferromagnetic flux-focusing lens simplifies inspections and increases detectability of fatigue cracks and material loss in high conductivity material. The unique feature of the device is the ferrous shield isolating a high-turn pick-up coil from an excitation coil. The use of the magnetic shield is shown to produce a null voltage output across the receiving coil in the presence of an unflawed sample. A redistribution of the current flow in the sample caused by the presence of flaws, however, eliminates the shielding condition and a large output voltage is produced, yielding a clear unambiguous flaw signal. The maximum sensor output is obtained when positioned symmetrically above the crack. Hence, by obtaining the position of the maximum sensor output, it is possible to track the fault and locate the area surrounding its tip. The accuracy of tip location is enhanced by two unique features of the sensor; a very high signal-to-noise ratio of the probe's output which results in an extremely smooth signal peak across the fault, and a rapidly decaying sensor output outside a small area surrounding the crack tip which enables the region for searching to be clearly defined. Under low frequency operation, material thinning due to corrosion damage causes an incomplete shielding of the pick-up coil. The low frequency output voltage of the probe is therefore a direct indicator of the thickness of the test sample.

  17. Focus on: neurotransmitter systems.

    PubMed

    Valenzuela, C Fernando; Puglia, Michael P; Zucca, Stefano

    2011-01-01

    Neurotransmitter systems have been long recognized as important targets of the developmental actions of alcohol (i.e., ethanol). Short- and long-term effects of ethanol on amino acid (e.g., γ-aminobutyric acid and glutamate) and biogenic amine (e.g., serotonin and dopamine) neurotransmitters have been demonstrated in animal models of fetal alcohol spectrum disorders (FASD). Researchers have detected ethanol effects after exposure during developmental periods equivalent to the first, second, and third trimesters of human pregnancy. Results support the recommendation that pregnant women should abstain from drinking-even small quantities-as effects of ethanol on neurotransmitter systems have been detected at low levels of exposure. Recent studies have elucidated new mechanisms and/or consequences of the actions of ethanol on amino acid and biogenic amine neuro-transmitter systems. Alterations in these neurotransmitter systems could, in part, be responsible for many of the conditions associated with FASD, including (1) learning, memory, and attention deficits; (2) motor coordination impairments; (3) abnormal responsiveness to stress; and (4) increased susceptibility to neuropsychiatric disorders, such as substance abuse and depression, and also neurological disorders, such as epilepsy and sudden infant death syndrome. However, future research is needed to conclusively establish a causal relationship between these conditions and developmental dysfunctions in neurotransmitter systems.

  18. Retroreflection Focusing Schlieren System

    NASA Technical Reports Server (NTRS)

    Heineck, James T. (Inventor)

    1996-01-01

    A retroreflective type focusing schlieren system which permits the light source to be positioned on the optic side of the system is introduced. The system includes an extended light source, as opposed to a point source, located adjacent to a beam splitter which projects light through the flow field onto a reflecting grating in the form of a grid which generates sheets of light that are directed back through the flow field and the beam splitter onto a primary lens behind which is located a cut-off grid having a grid pattern which corresponds to the grid pattern of the reflecting grating. The cut-off grid is adjustably positioned behind the primary lens and an image plane for imaging the turbulence is adjustably located behind the cut-off grid.

  19. Focused Ultrasound and Lithotripsy.

    PubMed

    Ikeda, Teiichiro; Yoshizawa, Shin; Koizumi, Norihiro; Mitsuishi, Mamoru; Matsumoto, Yoichiro

    2016-01-01

    Shock wave lithotripsy has generally been a first choice for kidney stone removal. The shock wave lithotripter uses an order of microsecond pulse durations and up to a 100 MPa pressure spike triggered at approximately 0.5-2 Hz to fragment kidney stones through mechanical mechanisms. One important mechanism is cavitation. We proposed an alternative type of lithotripsy method that maximizes cavitation activity to disintegrate kidney stones using high-intensity focused ultrasound (HIFU). Here we outline the method according to the previously published literature (Matsumoto et al., Dynamics of bubble cloud in focused ultrasound. Proceedings of the second international symposium on therapeutic ultrasound, pp 290-299, 2002; Ikeda et al., Ultrasound Med Biol 32:1383-1397, 2006; Yoshizawa et al., Med Biol Eng Comput 47:851-860, 2009; Koizumi et al., A control framework for the non-invasive ultrasound the ragnostic system. Proceedings of 2009 IEEE/RSJ International Conference on Intelligent Robotics and Systems (IROS), pp 4511-4516, 2009; Koizumi et al., IEEE Trans Robot 25:522-538, 2009). Cavitation activity is highly unpredictable; thus, a precise control system is needed. The proposed method comprises three steps of control in kidney stone treatment. The first step is control of localized high pressure fluctuation on the stone. The second step is monitoring of cavitation activity and giving feedback on the optimized ultrasound conditions. The third step is stone tracking and precise ultrasound focusing on the stone. For the high pressure control we designed a two-frequency wave (cavitation control (C-C) waveform); a high frequency ultrasound pulse (1-4 MHz) to create a cavitation cloud, and a low frequency trailing pulse (0.5 MHz) following the high frequency pulse to force the cloud into collapse. High speed photography showed cavitation collapse on a kidney stone and shock wave emission from the cloud. We also conducted in-vitro erosion tests of model and natural

  20. Focused Ultrasound and Lithotripsy.

    PubMed

    Ikeda, Teiichiro; Yoshizawa, Shin; Koizumi, Norihiro; Mitsuishi, Mamoru; Matsumoto, Yoichiro

    2016-01-01

    Shock wave lithotripsy has generally been a first choice for kidney stone removal. The shock wave lithotripter uses an order of microsecond pulse durations and up to a 100 MPa pressure spike triggered at approximately 0.5-2 Hz to fragment kidney stones through mechanical mechanisms. One important mechanism is cavitation. We proposed an alternative type of lithotripsy method that maximizes cavitation activity to disintegrate kidney stones using high-intensity focused ultrasound (HIFU). Here we outline the method according to the previously published literature (Matsumoto et al., Dynamics of bubble cloud in focused ultrasound. Proceedings of the second international symposium on therapeutic ultrasound, pp 290-299, 2002; Ikeda et al., Ultrasound Med Biol 32:1383-1397, 2006; Yoshizawa et al., Med Biol Eng Comput 47:851-860, 2009; Koizumi et al., A control framework for the non-invasive ultrasound the ragnostic system. Proceedings of 2009 IEEE/RSJ International Conference on Intelligent Robotics and Systems (IROS), pp 4511-4516, 2009; Koizumi et al., IEEE Trans Robot 25:522-538, 2009). Cavitation activity is highly unpredictable; thus, a precise control system is needed. The proposed method comprises three steps of control in kidney stone treatment. The first step is control of localized high pressure fluctuation on the stone. The second step is monitoring of cavitation activity and giving feedback on the optimized ultrasound conditions. The third step is stone tracking and precise ultrasound focusing on the stone. For the high pressure control we designed a two-frequency wave (cavitation control (C-C) waveform); a high frequency ultrasound pulse (1-4 MHz) to create a cavitation cloud, and a low frequency trailing pulse (0.5 MHz) following the high frequency pulse to force the cloud into collapse. High speed photography showed cavitation collapse on a kidney stone and shock wave emission from the cloud. We also conducted in-vitro erosion tests of model and natural

  1. Alliance-focused training.

    PubMed

    Eubanks-Carter, Catherine; Muran, J Christopher; Safran, Jeremy D

    2015-06-01

    Alliance-focused training (AFT) aims to increase therapists' ability to recognize, tolerate, and negotiate alliance ruptures by increasing the therapeutic skills of self-awareness, affect regulation, and interpersonal sensitivity. In AFT, therapists are encouraged to draw on these skills when metacommunicating about ruptures with patients. In this article, we present the 3 main supervisory tasks of AFT: videotape analysis of rupture moments, awareness-oriented role-plays, and mindfulness training. We describe the theoretical and empirical support for each supervisory task, provide examples based on actual supervision sessions, and present feedback about the usefulness of the techniques from trainees in our program. We also note some of the challenges involved in conducting AFT and the importance of maintaining a strong supervisory alliance when using this training approach.

  2. Alliance-focused training.

    PubMed

    Eubanks-Carter, Catherine; Muran, J Christopher; Safran, Jeremy D

    2015-06-01

    Alliance-focused training (AFT) aims to increase therapists' ability to recognize, tolerate, and negotiate alliance ruptures by increasing the therapeutic skills of self-awareness, affect regulation, and interpersonal sensitivity. In AFT, therapists are encouraged to draw on these skills when metacommunicating about ruptures with patients. In this article, we present the 3 main supervisory tasks of AFT: videotape analysis of rupture moments, awareness-oriented role-plays, and mindfulness training. We describe the theoretical and empirical support for each supervisory task, provide examples based on actual supervision sessions, and present feedback about the usefulness of the techniques from trainees in our program. We also note some of the challenges involved in conducting AFT and the importance of maintaining a strong supervisory alliance when using this training approach. PMID:25150677

  3. Focusing on customer service.

    PubMed

    1996-01-01

    This booklet is devoted to a consideration of how good customer service in family planning programs can generate demand for products and services, bring customers back, and reduce costs. Customer service is defined as increasing client satisfaction through continuous concern for client preferences, staff accountability to clients, and respect for the rights of clients. Issues discussed include the introduction of a customer service approach and gaining staff commitment. The experience of PROSALUD in Bolivia in recruiting appropriate staff, supervising staff, soliciting client feedback, and marketing services is offered as an example of a successful customer service approach. The key customer service functions are described as 1) establishing a welcoming atmosphere, 2) streamlining client flow, 3) personalizing client services, and 4) organizing and providing clear information to clients. The role of the manager in developing procedures is explored, and the COPE (Client-Oriented Provider-Efficient) process is presented as a good way to begin to make improvements. Techniques in staff training in customer service include brainstorming, role playing, using case studies (examples of which are provided), and engaging in practice sessions. Training also leads to the development of effective customer service attitudes, and the differences between these and organizational/staff-focused attitudes are illustrated in a chart. The use of communication skills (asking open-ended questions, helping clients express their concerns, engaging in active listening, and handling difficult situations) is considered. Good recovery skills are important when things go wrong. Gathering and using client feedback is the next topic considered. This involves identifying, recording, and discussing customer service issues as well as taking action on these issues and evaluating the results. The booklet ends by providing a sample of customer service indicators, considering the maintenance of a

  4. Detection of virulence factors of Escherichia coli focused on prevalence of EAST1 toxin in stool of diarrheic and non-diarrheic piglets and presence of adhesion involving virulence factors in astA positive strains.

    PubMed

    Zajacova, Zuzana Sramkova; Konstantinova, Lucie; Alexa, Pavel

    2012-01-27

    Between 2005 and 2009, a total of 800 Escherichia coli strains isolated from piglets with diarrhea were tested for the presence of enteroaggregative heat-stable enterotoxin EAST1, heat-labile (LT) and heat-stable enterotoxins (STa) and shigatoxin (Stx2e) by PCR with the purpose of investigating the present distribution of virulence factors on swine farms in the Czech Republic. The isolates were analyzed for their O-serogroup, fimbrial (K88, K99, 987P, F41, F18) and nonfimbrial adhesins (adhesin involved in diffuse adherence AIDA and porcine attaching and effacing-associated factor PAA). The detection rates of ETEC and STEC isolates were 36.5% and 7.75%, respectively, which implies that ETEC play the major role in E. coli infections in Czech herds. Generally, the most common serotype was O149:K88 which possessed genetic determinants for LT and EAST1. None of the tested E. coli isolates was positive for genes K99, 987P and F41. It was shown that out of 800 E. coli strains isolated from pigs, 277 were EAST1 positive and 74% from the latter were identified as ETEC. Of the fimbrial adhesins, K88 and F18 were commonly detected. Over 80% of K88/EAST1 positive strains possessed the gene for paa. We detected no EAE isolate positive for fimbrial adhesins or PAA and AIDA. The AIDA was more often associated with F18 than with K88. The gene astA was also identified among E. coli isolates of non-diarrheic piglets. We tested rectal swab samples collected from apparently healthy piglets on three farms. On all farms, E. coli astA positive strains (26.66%, 90.00% and 46.66% astA positive animals) were isolated. Our results showed a significantly higher prevalence of astA positive E. coli isolates among apparently healthy piglets in comparison with diarrheic piglets. The question remains as to what is the role of the astA gene in the pathogenesis of porcine colibacillosis and as a virulence factor. PMID:21864997

  5. Gas chromatography-electron capture detection determination of Dacthal and its di-acid metabolite in soil after ultrasound-assisted extraction and in situ focused microwave-assisted derivatization.

    PubMed

    Caballo-López, A; Luque de Castro, M D

    2006-09-01

    A quantitative method for the determination of Dacthal and its di-acid metabolite in soil has been developed by coupling ultrasound-assisted extraction and microwave-assisted derivatization of the analytes prior to gas chromatography-electron capture detection for individual separation and measurement. The main factors affecting both extraction efficiency and derivatization were optimized by experimental design methodology. The proposed approach allows extraction of these pollutants from spiked sediment and soil with efficiencies similar to those provided by the reference method but with a drastic reduction of both the extraction and derivatization times. The repeatability of the analyses, expressed as RSD, of Dacthal and its di-acid metabolite was 4.6% and 5.4%, respectively; meanwhile, the RSD for within-laboratory reproducibility was 8.7% and 9.2%, respectively.

  6. Focusing on flu

    PubMed Central

    Short, Mary B; Middleman, Amy B

    2014-01-01

    Introduction: To describe adolescents' perspectives regarding the use of school-located immunization programs (SLIP) for influenza vaccination. More importantly, adolescents were asked what factors would make them more or less likely to use a SLIP offering influenza vaccine. Results: Participants were generally found to be knowledgeable about influenza and to have positive attitudes toward receiving the vaccine via SLIP. Students were more willing to participate in a SLIP if it were low cost or free, less time-consuming than going to a doctor, and if they felt they could trust vaccinators. Overall, high school and middle school students ranked the benefits of SLIP similarly to each other. Methods: Focus groups using nominal group method were conducted with middle and high school students in a large, urban school district. Responses were recorded by each school, and then, responses were ranked across all participating schools for each question. Conclusions: A wide range of issues are important to middle and high school students when considering participation in SLIPs including convenience, public health benefits, trust in the program, program safety, and sanitary issues. Further research will be needed regarding the generalizability of these findings to larger populations of students. PMID:24018398

  7. Locally focused MRI

    NASA Astrophysics Data System (ADS)

    Yao, Lian; Cao, Y.; Levin, David N.

    1995-08-01

    Conventional magnetic resonance images are reconstructed by Fourier transformation and have uniform spatial resolution across the entire field of view (FOV). This paper describes a way of creating MR images which have higher spatial resolution in some areas than others. High resolution imaging can be confined to just those areas where it is necessary to resolve strong edges without truncation artifacts. Such locally focused images can be acquired in less scan time than required to image the entire FOV with uniformly high resolution. After the user specifies the spatial resolution in each portion of the FOV, the algorithm automatically generates image basis functions which oscillate most rapidly in the regions with highest resolution. Images are reconstructed by summing image projection onto these basis functions. These projections are calculated from a subset of the usual phase-encoded signals required to create a uniformly well-resolved image. The algorithm also determines which phase-encodings are optimal for this purpose, and these are usually nonuniformly scattered in k-space. Thus, both data acquisition and image reconstruction are optimized. Functional and interventional imaging may benefit from this technique, which makes it possible to acquire a rapid series of dynamical images which have high resolution in areas of expected changes and lower resolution elsewhere. Spectroscopic images may be improved by using high resolution in the neighborhood of sharp edges which might otherwise cause truncation artifacts.

  8. Focus point supersymmetry redux

    NASA Astrophysics Data System (ADS)

    Feng, Jonathan L.; Matchev, Konstantin T.; Sanford, David

    2012-04-01

    Recent results from Higgs boson and supersymmetry searches at the Large Hadron Collider provide strong new motivations for supersymmetric theories with heavy superpartners. We reconsider focus point supersymmetry (FP SUSY), in which all squarks and sleptons may have multi-TeV masses without introducing fine-tuning in the weak scale with respect to variations in the fundamental SUSY-breaking parameters. We examine both FP SUSY and its familiar special case, the FP region of minimal supergravity, also known as the constrained minimal supersymmetric standard model (mSUGRA/CMSSM), and show that they are beautifully consistent with all particle, astroparticle, and cosmological data, including Higgs boson mass limits, null results from SUSY searches, electric dipole moments, b→sγ, Bs→μ+μ-, the thermal relic density of neutralinos, and dark matter searches. The observed deviation of the muon’s anomalous magnetic moment from its standard model value may also be explained in FP SUSY, although not in the FP region of mSUGRA/CMSSM. In light of recent data, we advocate refined searches for FP SUSY and related scenarios with heavy squarks and sleptons, and we present a simplified parameter space within mSUGRA/CMSSM to aid such analyses.

  9. COMPRENDO: Focus and Approach

    PubMed Central

    Schulte-Oehlmann, Ulrike; Albanis, Triantafyllos; Allera, Axel; Bachmann, Jean; Berntsson, Pia; Beresford, Nicola; Carnevali, Daniela Candia; Ciceri, Francesca; Dagnac, Thierry; Falandysz, Jerzy; Galassi, Silvana; Hala, David; Janer, Gemma; Jeannot, Roger; Jobling, Susan; King, Isabella; Klingmüller, Dietrich; Kloas, Werner; Kusk, Kresten Ole; Levada, Ramon; Lo, Susan; Lutz, Ilka; Oehlmann, Jörg; Oredsson, Stina; Porte, Cinta; Rand-Weaver, Marian; Sakkas, Vasilis; Sugni, Michela; Tyler, Charles; van Aerle, Ronny; van Ballegoy, Christoph; Wollenberger, Leah

    2006-01-01

    Tens of thousands of man-made chemicals are in regular use and discharged into the environment. Many of them are known to interfere with the hormonal systems in humans and wildlife. Given the complexity of endocrine systems, there are many ways in which endocrine-disrupting chemicals (EDCs) can affect the body’s signaling system, and this makes unraveling the mechanisms of action of these chemicals difficult. A major concern is that some of these EDCs appear to be biologically active at extremely low concentrations. There is growing evidence to indicate that the guiding principle of traditional toxicology that “the dose makes the poison” may not always be the case because some EDCs do not induce the classical dose–response relationships. The European Union project COMPRENDO (Comparative Research on Endocrine Disrupters—Phylogenetic Approach and Common Principles focussing on Androgenic/Antiandrogenic Compounds) therefore aims to develop an understanding of potential health problems posed by androgenic and antiandrogenic compounds (AACs) to wildlife and humans by focusing on the commonalities and differences in responses to AACs across the animal kingdom (from invertebrates to vertebrates). PMID:16818253

  10. A study on the flip angle for an optimal T1-weighted image based on the 3D-THRIVE MRI technique: Focusing on the detection of a hepatocellular carcinoma (HCC)

    NASA Astrophysics Data System (ADS)

    Dong, Kyung-Rae; Goo, Eun-Hoe; Lee, Jae-Seung; Chung, Woon-Kwan; Kim, Young-Jae

    2014-04-01

    This study examined the optimal flip angle (FA) for a T1-weighted image in the detection of a hepatocellular carcinoma (HCC). A 3D-T1-weighted high-resolution isotropic volume examination (THRIVE) technique was used to determine the dependence of the signal to noise ratio (SNR) and the contrast-to-noise ratio (CNR) on the change in FA. This study targeted 40 liver cancer patients (25 men and 15 women aged 50 to 70 years with a mean age of 60.32 ± 6.2 years) who visited this hospital to undergo an abdominal MRI examination from January to June 2013. A 3.0 Tesla MRI machine (Philips, Medical System, Achieva) and a MRI receiver coil for data reception with a 16-channel multicoil were used in this study. The THRIVE (repetition time (TR): 8.1 ms, echo time (TE): 3.7 ms, matrix: 172 × 172, slice thickness: 4 mm, gap: 2 mm, field of view (FOV): 350 mm, and band width (BW): 380.1 Hz) technique was applied as a pulse sequence. The time required for the examination was 19 seconds, and the breath-hold technique was used. Axial images were obtained at five FAs: 5, 10, 15, 20 and 25°. The signal intensities of the liver, the lesion and the background noise were measured based on the acquired images before the SNR and the CNR were calculated. To evaluate the image at the FA, we used SPSS for Windows ver. 17.0 to conduct a one-way ANOVA test. A Bonferroni test was conducted as a post-hoc test. The SNRs of the hemorrhagic HCC in the 3D-THRIVE technique were 35.50 ± 4.12, 97.00 ± 10.24, 66.09 ± 7.29, 53.84 ± 5.43, and 42.92 ± 5.11 for FAs of 5, 10, 15, 20, and 25°, respectively (p = 0.0430), whereas the corresponding CNRs were 30.50 ± 3.84, 43.00 ± 5.42, 36.54 ± 4.09, 32.30 ± 2.79, and 31.69 ± 3.21 (p = 0.0003). At a small FA of 10, the SNR and the CNR showed the highest values. As the FA was increased, the SNR and the CNR values showed a decreasing tendency. In conclusion, the optimal T1-weighted image FA should be set to 10° to detect a HCC by using the 3D

  11. EDITORIAL: Focus on Graphene

    NASA Astrophysics Data System (ADS)

    Peres, N. M. R.; Ribeiro, Ricardo M.

    2009-09-01

    Graphene physics is currently one of the most active research areas in condensed matter physics. Countless theoretical and experimental studies have already been performed, targeting electronic, magnetic, thermal, optical, structural and vibrational properties. Also, studies that modify pristine graphene, aiming at finding new physics and possible new applications, have been considered. These include patterning nanoribbons and quantum dots, exposing graphene's surface to different chemical species, studying multilayer systems, and inducing strain and curvature (modifying in this way graphene's electronic properties). This focus issue includes many of the latest developments on graphene research. Focus on Graphene Contents Electronic properties of graphene and graphene nanoribbons with 'pseudo-Rashba' spin-orbit coupling Tobias Stauber and John Schliemann Strained graphene: tight-binding and density functional calculations R M Ribeiro, Vitor M Pereira, N M R Peres, P R Briddon and A H Castro Neto The effect of sublattice symmetry breaking on the electronic properties of doped graphene A Qaiumzadeh and R Asgari Interfaces within graphene nanoribbons J Wurm, M Wimmer, I Adagideli, K Richter and H U Baranger Weak localization and transport gap in graphene antidot lattices J Eroms and D Weiss Electronic properties of graphene antidot lattices J A Fürst, J G Pedersen, C Flindt, N A Mortensen, M Brandbyge, T G Pedersen and A-P Jauho Splitting of critical energies in the n=0 Landau level of graphene Ana L C Pereira Double-gated graphene-based devices S Russo, M F Craciun, M Yamamoto, S Tarucha and A F Morpurgo Pinning and switching of magnetic moments in bilayer graphene Eduardo V Castro, M P López-Sancho and M A H Vozmediano Electronic transport properties of graphene nanoribbons Katsunori Wakabayashi, Yositake Takane, Masayuki Yamamoto and Manfred Sigrist Many-body effects on out-of-plane phonons in graphene J González and E Perfetto Graphene zigzag ribbons, square

  12. Prostate Focused Ultrasound Therapy.

    PubMed

    Chapelon, Jean-Yves; Rouvière, Olivier; Crouzet, Sébastien; Gelet, Albert

    2016-01-01

    The tremendous progress in engineering and computing power coupled with ultrasound transducer technology and imaging modalities over the past 20 years have encouraged a revival of clinical interest in ultrasound therapy, mainly in High-Intensity Focused Ultrasound (HIFU). So far, the most extensive results from HIFU obtained in urology involve transrectal prostate ablation, which appears to be an effective therapeutic alternative for patients with malignant prostate tumors. Prostate cancer (PCa) is one of the most frequently diagnosed cancers in men. Several treatment options with different therapeutic approaches exist, including HIFU for localized PCa that has been in use for over 15 years. Since the early 2000s, two systems have been marketed for this application, and other devices are currently in clinical trials. HIFU treatment can be used either alone or in combination with (before- or after-) external beam radiotherapy (EBRT) (before or after HIFU) and can be repeated multiple times. HIFU treatment is performed under real-time monitoring with ultrasound or guided by MRI. Two indications are validated today: Primary care treatment and EBRT failure. The results of HIFU for primary care treatment are similar to standard conformal EBRT, even though no randomized comparative studies have been performed and no 10-year follow up data is yet available for HIFU. Salvage HIFU after EBRT failure is increasing with oncological outcomes, similar to those achieved with surgery but with the advantage of fewer adverse effects. HIFU is an evolving technology perfectly adapted for focal treatment. Thus, HIFU focal therapy is another pathway that must be explored when considering the accuracy and reliability for PCa mapping techniques. HIFU would be particularly suited for such a therapy since it is clear that HIFU outcomes and toxicity are relative to the volume of prostate treated.

  13. Cable Diagnostic Focused Initiative

    SciTech Connect

    Hartlein, R.A.; Hampton, R.N.

    2010-12-30

    This report summarizes an extensive effort made to understand how to effectively use the various diagnostic technologies to establish the condition of medium voltage underground cable circuits. These circuits make up an extensive portion of the electric delivery infrastructure in the United States. Much of this infrastructure is old and experiencing unacceptable failure rates. By deploying efficient diagnostic testing programs, electric utilities can replace or repair circuits that are about to fail, providing an optimal approach to improving electric system reliability. This is an intrinsically complex topic. Underground cable systems are not homogeneous. Cable circuits often contain multiple branches with different cable designs and a range of insulation materials. In addition, each insulation material ages differently as a function of time, temperature and operating environment. To complicate matters further, there are a wide variety of diagnostic technologies available for assessing the condition of cable circuits with a diversity of claims about the effectiveness of each approach. As a result, the benefits of deploying cable diagnostic testing programs have been difficult to establish, leading many utilities to avoid the their use altogether. This project was designed to help address these issues. The information provided is the result of a collaborative effort between Georgia Tech NEETRAC staff, Georgia Tech academic faculty, electric utility industry participants, as well as cable system diagnostic testing service providers and test equipment providers. Report topics include: •How cable systems age and fail, •The various technologies available for detecting potential failure sites, •The advantages and disadvantages of different diagnostic technologies, •Different approaches for utilities to employ cable system diagnostics. The primary deliverables of this project are this report, a Cable Diagnostic Handbook (a subset of this report) and an online

  14. The design of aerial camera focusing mechanism

    NASA Astrophysics Data System (ADS)

    Hu, Changchang; Yang, Hongtao; Niu, Haijun

    2015-10-01

    In order to ensure the imaging resolution of aerial camera and compensating defocusing caused by the changing of atmospheric temperature, pressure, oblique photographing distance and other environmental factor [1,2], and to meeting the overall design requirements of the camera for the lower mass and smaller size , the linear focusing mechanism is designed. Through the target surface support, the target surface component is connected with focusing driving mechanism. Make use of precision ball screws, focusing mechanism transforms the input rotary motion of motor into linear motion of the focal plane assembly. Then combined with the form of linear guide restraint movement, the magnetic encoder is adopted to detect the response of displacement. And the closed loop control is adopted to realize accurate focusing. This paper illustrated the design scheme for a focusing mechanism and analyzed its error sources. It has the advantages of light friction and simple transmission chain and reducing the transmission error effectively. And this paper also analyses the target surface by finite element analysis and lightweight design. Proving that the precision of focusing mechanism can achieve higher than 3um, and the focusing range is +/-2mm.

  15. Isoelectric focusing of proteins and peptides

    NASA Technical Reports Server (NTRS)

    Egen, N.

    1979-01-01

    Egg-white solution was chosen as the reference solution in order to assess the effects of operational parameters (voltage, flow rate, ampholine pH range and concentration, and protein concentration) of the RIEF apparatus on protein resolution. Topics of discussion include: (1) comparison of RIEF apparatus to conventional IEF techniques (column and PAG) with respect to resolution and throughput; (2) peptide and protein separation (AHF, Thymosin - Fraction 5, vasoactive peptide, L-asparaginase and ACP); and (3) detection of peptides - dansyl derivatives of amino acids and peptides, post-focusing fluorescent labeling of amino acids, peptides and proteins, and ampholine extraction from focused gels.

  16. Dual focus diffractive optical element with extended depth of focus

    NASA Astrophysics Data System (ADS)

    Uno, Katsuhiro; Shimizu, Isao

    2014-09-01

    A dual focus property and an extended depth of focus were verified by a new type of diffractive lens displaying on liquid crystal on silicon (LCoS) devices. This type of lens is useful to read information on multilayer optical discs and tilted discs. The radial undulation of the phase groove on the diffractive lens gave the dual focus nature. The focal extension was performed by combining the dual focus lens with the axilens that was invented for expanding the depth of focus. The number of undulations did not affect the intensity along the optical axis but the central spot of the diffraction pattern.

  17. Focusators for laser-branding

    NASA Astrophysics Data System (ADS)

    Doskolovich, L. L.; Kazanskiy, N. L.; Kharitonov, S. I.; Uspleniev, G. V.

    A new method is investigated for synthesis of computer-generated optical elements: focusators that are able to focus the radial-symmetrical laser beam into complex focal contours, in particular into alphanumeric symbols. The method is based on decomposition of the focal contour into segments of straight lines and semi-circles, following corresponding spacing out of the focusator on elementary segments (concentric rings or sectors) and solution of the inverse task of focusing from focusator segments into corresponding elements of the focal contour. The results of numerical computing of the field from synthesized focusators into the letters are presented. The theoretical efficiency of the focusators discussed is no less than 85%. The amplitude masks and the results of operational studies of synthesized focusators are presented.

  18. Focusing Electron Beams at SLAC.

    ERIC Educational Resources Information Center

    Taylor, Richard L.

    1993-01-01

    Describes the development of a set of magnets that focus high-energy electron and positron beams causing them to collide, annihilate each other, and generate new particles. Explains how dipoles bend the beam, how quadrupoles focus the beam, how the focal length is calculated, and the superconducting final focus. (MDH)

  19. The theory of ionospheric focused heating

    NASA Technical Reports Server (NTRS)

    Bernhardt, P. A.; Duncan, L. M.

    1987-01-01

    Ionospheric modification by high power radio waves and by chemical releases are combined in a theoretical study of ionospheric focused heating. The release of materials which promote electron-ion recombination creates a hole in the bottomside ionosphere. The ionospheric hole focuses high power radio waves from a ground-based transmitter to give a 20 dB or greater enhancement in power density. The intense radio beam excites atomic oxygen by collisions with accelerated electrons. Airglow from the excited oxygen provides a visible trace of the focused beam. The large increase in the intensity of the radio beam stimulates new wave-plasma interactions. Numerical simulations show that the threshold for the two-plasmon decay instability is exceeded. The interaction of the pump electromagnetic wave with the backward plasmon produces a scattered electromagnetic wave at 3/2 the pump frequency. The scattered wave provides a unique signature of the two-plasmon decay process for ground-based detection.

  20. Frequency-dependent ultrasound-induced transformation in E. coli.

    PubMed

    Deeks, Jeremy; Windmill, James; Agbeze-Onuma, Maduka; Kalin, Robert M; Argondizza, Peter; Knapp, Charles W

    2014-12-01

    Ultrasound-enhanced gene transfer (UEGT) is continuing to gain interest across many disciplines; however, very few studies investigate UEGT efficiency across a range of frequencies. Using a variable frequency generator, UEGT was tested in E. coli at six ultrasonic frequencies. Results indicate frequency can significantly influence UEGT efficiency positively and negatively. A frequency of 61 kHz improved UEGT efficiency by ~70 % higher, but 99 kHz impeded UEGT to an extent worse than no ultrasound exposure. The other four frequencies (26, 133, 174, and 190 kHz) enhanced transformation compared to no ultrasound, but efficiencies did not vary. The influence of frequency on UEGT efficiency was observed across a range of operating frequencies. It is plausible that frequency-dependent dynamics of mechanical and chemical energies released during cavitational-bubble collapse (CBC) are responsible for observed UEGT efficiencies.

  1. Understanding ultrasound induced sonoporation: definitions and underlying mechanisms.

    PubMed

    Lentacker, I; De Cock, I; Deckers, R; De Smedt, S C; Moonen, C T W

    2014-06-01

    In the past two decades, research has underlined the potential of ultrasound and microbubbles to enhance drug delivery. However, there is less consensus on the biophysical and biological mechanisms leading to this enhanced delivery. Sonoporation, i.e. the formation of temporary pores in the cell membrane, as well as enhanced endocytosis is reported. Because of the variety of ultrasound settings used and corresponding microbubble behavior, a clear overview is missing. Therefore, in this review, the mechanisms contributing to sonoporation are categorized according to three ultrasound settings: i) low intensity ultrasound leading to stable cavitation of microbubbles, ii) high intensity ultrasound leading to inertial cavitation with microbubble collapse, and iii) ultrasound application in the absence of microbubbles. Using low intensity ultrasound, the endocytotic uptake of several drugs could be stimulated, while short but intense ultrasound pulses can be applied to induce pore formation and the direct cytoplasmic uptake of drugs. Ultrasound intensities may be adapted to create pore sizes correlating with drug size. Small molecules are able to diffuse passively through small pores created by low intensity ultrasound treatment. However, delivery of larger drugs such as nanoparticles and gene complexes, will require higher ultrasound intensities in order to allow direct cytoplasmic entry.

  2. Ultrasound-Induced New Cellular Mechanism Involved in Drug Resistance

    PubMed Central

    Hassan, Mariame A.; Furusawa, Yukihiro; Minemura, Masami; Rapoport, Natalya; Sugiyama, Toshiro; Kondo, Takashi

    2012-01-01

    The acoustic effects in a biological milieu offer several scenarios for the reversal of multidrug resistance. In this study, we have observed higher sensitivity of doxorubicin-resistant uterine sarcoma MES-SA/DX5 cells to ultrasound exposure compared to its parent counterpart MES-SA cells; however, the results showed that the acoustic irradiation was genotoxic and could promote neotic division in exposed cells that was more pronounced in the resistant variant. The neotic progeny, imaged microscopically 24 hr post sonication, could contribute in modulating the final cell survival when an apoptotic dose of doxorubicin was combined with ultrasound applied either simultaneously or sequentially in dual-treatment protocols. Depending on the time and order of application of ultrasound and doxorubicin in combination treatments, there was either desensitization of the parent cells or sensitization of the resistant cells to doxorubicin action. PMID:23284614

  3. Ultrasound induced green solvent extraction of oil from oleaginous seeds.

    PubMed

    Sicaire, Anne-Gaëlle; Vian, Maryline Abert; Fine, Frédéric; Carré, Patrick; Tostain, Sylvain; Chemat, Farid

    2016-07-01

    Ultrasound-assisted extraction of rapeseed oil was investigated and compared with conventional extraction for energy efficiency, throughput time, extraction yield, cleanness, processing cost and product quality. A multivariate study enabled us to define optimal parameters (7.7 W/cm(2) for ultrasonic power intensity, 40 °C for processing temperature, and a solid/liquid ratio of 1/15) for ultrasound-assisted extraction of oil from oilseeds to maximize lipid yield while reducing solvent consumption and extraction time using response surface methodology (RSM) with a three-variable central composite design (CCD). A significant difference in oil quality was noted under the conditions of the initial ultrasound extraction, which was later avoided using ultrasound in the absence of oxygen. Three concepts of multistage cross-current extraction were investigated and compared: conventional multistage maceration, ultrasound-assisted maceration and a combination, to assess the positive impact of using ultrasound on the seed oil extraction process. The study concludes that ultrasound-assisted extraction of oil is likely to reduce both economic and ecological impacts of the process in the fat and oil industry.

  4. Double Bifurcation of Nilpotent Focus

    NASA Astrophysics Data System (ADS)

    Liu, Yirong; Li, Feng

    In this paper, an interesting bifurcation phenomenon is investigated — a 3-multiple nilpotent focus of the planar dynamical systems could be broken into two element focuses and an element saddle, and the limit cycles could bifurcate out from two element focuses. As an example, a class of cubic systems with 3-multiple nilpotent focus O(0, 0) is investigated, we prove that nine limit cycles with the scheme 7 ⊃ (1 ∪ 1) could bifurcate out from the origin when the origin is a weak focus of order 8. At the end of this paper, the double bifurcations of a class of Z2 equivalent cubic system with 3-multiple nilpotent focus or center O(0, 0) are investigated.

  5. Focus Groups Help To Focus the Marketing Strategy.

    ERIC Educational Resources Information Center

    Ashar, Hanna; Lane, Maureen

    1996-01-01

    A university-based degree completion program for adults conducted focus group research to refine market positioning and promotion. Focus groups averaged five current students and recent graduates who reflected, demographically, the current student population. Results gave insight into reasons for selecting the university, aspects of the program…

  6. Pharmacometrics: Focus on the Patient

    PubMed Central

    Dumitrescu, T Pene; Fossler, MJ; Schmith, VD

    2015-01-01

    Pharmacometrics, whether using simple or complex models, has contributed to rational and efficient drug development,1–3 with the main focus on early drug development.4 This article describes why opportunities more directly focused on the patient abound in late stage development, illustrating the concept with three innovative examples which focus on benefits to patients, enabling drugs that are truly efficacious to reach the market faster in diseases with high unmet medical needs, while maintaining adequate safety. PMID:26225220

  7. CTE's Focus on Continuous Improvement

    ERIC Educational Resources Information Center

    Foster, John; Kelley, Patricia; Pritz, Sandy; Hodes, Carol

    2011-01-01

    Just one of the ways career and technical education (CTE) is revamping its image is through increased attention to data-driven instructional techniques as a means of improving and focusing instruction on what matters most. Accountability and data have increasingly become a core focus of research, news, and commentary about education in recent…

  8. Ultrasonic inspection apparatus and method using a focused wave device

    DOEpatents

    Gieske, John H.; Roach, Dennis P.; Walkington, Phillip D.

    2001-01-01

    An ultrasonic pulse echo inspection apparatus and method for detecting structural failures. A focus lens is coupled to the transducer to focus the ultrasonic signal on an area to be inspected and a stop is placed in the focus lens to block selected ultrasonic waves. Other waves are not blocked and are transmitted through the structure to arrive at interfaces therein concurrently to produce an echo response with significantly less distortion.

  9. EDITORIAL: Focus on Quantum Control

    NASA Astrophysics Data System (ADS)

    Rabitz, Herschel

    2009-10-01

    represent two-photon power spectra of arbitrarily and adaptively shaped broadband laser pulses M A Montgomery and N H Damrauer Accurate and efficient implementation of the von Neumann representation for laser pulses with discrete and finite spectra Frank Dimler, Susanne Fechner, Alexander Rodenberg, Tobias Brixner and David J Tannor Coherent strong-field control of multiple states by a single chirped femtosecond laser pulse M Krug, T Bayer, M Wollenhaupt, C Sarpe-Tudoran, T Baumert, S S Ivanov and N V Vitanov Quantum-state measurement of ionic Rydberg wavepackets X Zhang and R R Jones On the paradigm of coherent control: the phase-dependent light-matter interaction in the shaping window Tiago Buckup, Jurgen Hauer and Marcus Motzkus Use of the spatial phase of a focused laser beam to yield mechanistic information about photo-induced chemical reactions V J Barge, Z Hu and R J Gordon Coherent control of multiple vibrational excitations for optimal detection S D McGrane, R J Scharff, M Greenfield and D S Moore Mode selectivity with polarization shaping in the mid-IR David B Strasfeld, Chris T Middleton and Martin T Zanni Laser-guided relativistic quantum dynamics Chengpu Liu, Markus C Kohler, Karen Z Hatsagortsyan, Carsten Muller and Christoph H Keitel Continuous quantum error correction as classical hybrid control Hideo Mabuchi Quantum filter reduction for measurement-feedback control via unsupervised manifold learning Anne E B Nielsen, Asa S Hopkins and Hideo Mabuchi Control of the temporal profile of the local electromagnetic field near metallic nanostructures Ilya Grigorenko and Anatoly Efimov Laser-assisted molecular orientation in gaseous media: new possibilities and applications Dmitry V Zhdanov and Victor N Zadkov Optimization of laser field-free orientation of a state-selected NO molecular sample Arnaud Rouzee, Arjan Gijsbertsen, Omair Ghafur, Ofer M Shir, Thomas Back, Steven Stolte and Marc J J Vrakking Controlling the sense of molecular rotation Sharly Fleischer

  10. Plutonium focus area: Technology summary

    SciTech Connect

    1996-03-01

    To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this approach, EM developed a management structure and principles that led to creation of specific focus areas. These organizations were designed to focus scientific and technical talent throughout DOE and the national scientific community on major environmental restoration and waste management problems facing DOE. The focus area approach provides the framework for inter-site cooperation and leveraging of resources on common problems. After the original establishment of five major focus areas within the Office of Technology Development (EM-50), the Nuclear Materials Stabilization Task Group (NMSTG, EM-66) followed EM-50`s structure and chartered the Plutonium Focus Area (PFA). NMSTG`s charter to the PFA, described in detail later in this book, plays a major role in meeting the EM-66 commitments to the Defense Nuclear Facilities Safety Board (DNFSB). The PFA is a new program for FY96 and as such, the primary focus of revision 0 of this Technology Summary is an introduction to the Focus Area; its history, development, and management structure, including summaries of selected technologies being developed. Revision 1 to the Plutonium Focus Area Technology Summary is slated to include details on all technologies being developed, and is currently planned for release in August 1996. The following report outlines the scope and mission of the Office of Environmental Management, EM-60, and EM-66 organizations as related to the PFA organizational structure.

  11. FOCUSing on Innovative Solar Technologies

    ScienceCinema

    Rohlfing, Eric; Holman, Zak, Angel, Roger

    2016-07-12

    Many of ARPA-E’s technology programs seek to break down silos and build new technological communities around a specific energy challenge. In this video, ARPA-E’s Deputy Director for Technology Eric Rohlfing, discusses how the Full-Spectrum Optimized Conversion and Utilization of Sunlight (FOCUS) program is bringing together the photovoltaic (PV) and concentrated solar power (CSP) communities to develop hybrid solar energy systems. This video features interviews with innovators from the FOCUS project team made up by Arizona State University and the University of Arizona, and showcases how the FOCUS program is combining.

  12. Compact electron beam focusing column

    SciTech Connect

    Persaud, Arun; Leung, Ka-Ngo; Reijonen, Jani

    2001-07-13

    A novel design for an electron beam focusing column has been developed at LBNL. The design is based on a low-energy spread multicusp plasma source which is used as a cathode for electron beam production. The focusing column is 10 mm in length. The electron beam is focused by means of electrostatic fields. The column is designed for a maximum voltage of 50 kV. Simulations of the electron trajectories have been performed by using the 2-D simulation code IGUN and EGUN. The electron temperature has also been incorporated into the simulations. The electron beam simulations, column design and fabrication will be discussed in this presentation.

  13. Best focus shift mitigation for extending the depth of focus

    NASA Astrophysics Data System (ADS)

    Szucs, A.; Planchot, J.; Farys, V.; Yesilada, E.; Alleaume, C.; Depre, L.; Dover, R.; Gourgon, C.; Besacier, M.; Nachtwein, A.; Rusu, P.

    2013-04-01

    The low-k1 domain of immersion lithography tends to result in much smaller depths of focus (DoF) compared to prior technology nodes. For 28 nm technology and beyond it is a challenge since (metal) layers have to deal with a wide range of structures. Beside the high variety of features, the reticle induced (mask 3D) effects became non-negligible. These mask 3D effects lead to best focus shift. In order to enhance the overlapping DoF, so called usable DoF (uDoF), alignment of each individual features best focus is required. So means the mitigation of the best focus shift. This study investigates the impact of mask 3D effects and the ability to correct the wavefront in order to extend the uDoF. The generation of the wavefront correction map is possible by using computational lithographic such Tachyon simulations software (from Brion). And inside the scanner the wavefront optimization is feasible by applying a projection lens modulator, FlexWaveTM (by ASML). This study explores both the computational lithography and scanner wavefront correction capabilities. In the first part of this work, simulations are conducted based on the determination and mitigation of best focus shift (coming from mask 3D effects) so as to improve the uDoF. In order to validate the feasibility of best focus shift decrease by wavefront tuning and mitigation results, the wavefront optimization provided correction maps are introduced into a rigorous simulator. Finally these results on best focus shift and uDoF are compared to wafers exposed using FlexWave then measured by scanning electron microscopy (SEM).

  14. Wolter Optics for Neutron Focusing

    NASA Technical Reports Server (NTRS)

    Mildner, D. F. R.; Gubarev, M. V.

    2010-01-01

    Focusing optics based on Wolter optical geometries developed for x-ray grazing incidence beams can be designed for neutron beams. Wolter optics are formed by grazing incidence reflections from two concentric conic sections (for example, a paraboloid and a hyperboloid). This has transformed observational X-ray astronomy by increasing the sensitivity by many orders of magnitude for research in astrophysics and cosmology. To increase the collection area, many reflecting mirrors of different diameters are nested with a common focal plane. These mirrors are fabricated using nickel-electroformed replication techniques. We apply these ideas to neutron focusing using nickel mirrors. We show an initial test of a conical mirror using a beam of cold neutrons. key words: electroformed nickel replication, focusing optics, grazing angle incidence, mirror reflection, neutron focusing, Wolter optics

  15. Wayside Teaching: Focusing on Relationships

    ERIC Educational Resources Information Center

    Powell, Sara Davis

    2011-01-01

    Wayside teaching focuses on building and maintaining positive relationships with students. Teachers can implement certain wayside teaching practices to end the year in a positive way and begin preparing for the next school year.

  16. Focusing liquid microjets with nozzles

    NASA Astrophysics Data System (ADS)

    Acero, A. J.; Ferrera, C.; Montanero, J. M.; Gañán-Calvo, A. M.

    2012-06-01

    The stability of flow focusing taking place in a converging-diverging nozzle, as well as the size of the resulting microjets, is examined experimentally in this paper. The results obtained in most aspects of the problem are similar to those of the classical plate-orifice configuration. There is, however, a notable difference between flow focusing in nozzles and in the plate-orifice configuration. In the former case, the liquid meniscus oscillates laterally (global whipping) for a significant area of the control parameter plane, a phenomenon never observed when focusing with the plate-orifice configuration. Global whipping may constitute an important drawback of flow focusing with nozzles because it reduces the robustness of the technique.

  17. Focusing light through living tissue

    NASA Astrophysics Data System (ADS)

    Vellekoop, I. M.; Aegerter, C. M.

    2010-02-01

    Tissues such as skin, fat or cuticle are non-transparent because inhomogeneities in the tissue scatter light. We demonstrate experimentally that light can be focused through turbid layers of living tissue, in spite of scattering. Our method is based on the fact that coherent light forms an interference pattern, even after hundreds of scattering events. By spatially shaping the wavefront of the incident laser beam, this interference pattern was modified to make the scattered light converge to a focus. In contrast to earlier experiments, where light was focused through solid objects, we focused light through living pupae of Drosophila melanogaster. We discuss a dynamic wavefront shaping algorithm that follows changes due to microscopic movements of scattering particles in real time. We relate the performance of the algorithm to the measured timescale of the changes in the speckle pattern and analyze our experiment in the light of Laser Doppler flowmetry. Applications in particle tracking, imaging, and optical manipulation are discussed.

  18. AXAF SIM focus mechanism study

    NASA Technical Reports Server (NTRS)

    Tananbaum, H. D.; Whitbeck, E.

    1994-01-01

    The design requirements and initial design concept for the AXAF-I Science Instrument Module (SIM) were reviewed at Ball on September 29, 1993. The concept design SIM focus mechanism utilizes a planetary gearset, with redundant motors, to drive a large ring (called 'main housing bearing') via a spur gearset. This large drive ring actuates three tangent bar links (called 'push rods'), which in turn actuate three levers (called 'pin levers'). Each of the three pin levers rotates an 'eccentric pin,' which in turn moves the base of a bipod flexure in both the radial (normal to optical axis) and axial (focus along optical axis) directions. Three bipod flexures are employed, equally spaced at 120 degrees apart, the base of each being translated in the two directions as described above. A focus adjustment is made by rotating the drive ring, which drives the push rods and therefore the pin levers, which in turn rotate the eccentric pins, finally imparting the two motions to the base of each of the bipod flexures. The axial translation (focus adjustment) of the focused structure is the sum of the direct axial motion plus axial motion which comes from uniformly squeezing the three bipod bases radially inward. SAO documented the following concerns regarding the focus mechanism in memo WAP-FY94-001, dated October 7, 1993: (1) The focus adjustment depends, in large part, on the structural properties (stiffnesses and end fixities) of the bipod flexures, push rods, pin levers and eccentric pins. If these properties are not matched very well, then lateral translations as well as unwanted rotations of the focussed structure will accompany focus motion. In addition, the stackup of linkage tolerances and any nonuniform wear in the linkages will result in the same unwanted motions. Thermal gradients will also affect these motions. At the review Ball did not present supporting analyses to support their choice of this design concept. (2) The proposed 'primary' method of measuring focus

  19. Focus cues affect perceived depth

    PubMed Central

    Watt, Simon J.; Akeley, Kurt; Ernst, Marc O.; Banks, Martin S.

    2007-01-01

    Depth information from focus cues—accommodation and the gradient of retinal blur—is typically incorrect in three-dimensional (3-D) displays because the light comes from a planar display surface. If the visual system incorporates information from focus cues into its calculation of 3-D scene parameters, this could cause distortions in perceived depth even when the 2-D retinal images are geometrically correct. In Experiment 1 we measured the direct contribution of focus cues to perceived slant by varying independently the physical slant of the display surface and the slant of a simulated surface specified by binocular disparity (binocular viewing) or perspective/texture (monocular viewing). In the binocular condition, slant estimates were unaffected by display slant. In the monocular condition, display slant had a systematic effect on slant estimates. Estimates were consistent with a weighted average of slant from focus cues and slant from disparity/texture, where the cue weights are determined by the reliability of each cue. In Experiment 2, we examined whether focus cues also have an indirect effect on perceived slant via the distance estimate used in disparity scaling. We varied independently the simulated distance and the focal distance to a disparity-defined 3-D stimulus. Perceived slant was systematically affected by changes in focal distance. Accordingly, depth constancy (with respect to simulated distance) was significantly reduced when focal distance was held constant compared to when it varied appropriately with the simulated distance to the stimulus. The results of both experiments show that focus cues can contribute to estimates of 3-D scene parameters. Inappropriate focus cues in typical 3-D displays may therefore contribute to distortions in perceived space. PMID:16441189

  20. Heating in vascular tissue and flow-through tissue phantoms induced by focused ultrasound

    NASA Astrophysics Data System (ADS)

    Huang, Jinlan

    High intensity focused ultrasound (HIFU) can be used to control bleeding, both from individual blood vessels as well as from gross damage to the capillary bed. This process, called acoustic hemostasis, is being studied in the hope that such a method would ultimately provide a lifesaving treatment during the so-called "golden hour", a brief grace period after a severe trauma in which prompt therapy can save the life of an injured person. Thermal effects play a major role in occlusion of small vessels and also appear to contribute to the sealing of punctures in major blood vessels. However, aggressive ultrasound-induced tissue heating can also impact healthy tissue and can lead to deleterious mechanical bioeffects. Moreover, the presence of vascularity can limit one's ability to elevate the temperature of blood vessel walls owing to convective heat transport. In an effort to better understand the heating process in tissues with vascular structure we have developed a numerical simulation that couples models for ultrasound propagation, acoustic streaming, ultrasound heating and blood cooling in Newtonian viscous media. The 3-D simulation allows for the study of complicated biological structures and insonation geometries. We have also undertaken a series of in vitro experiments, in non-uniform flow-through tissue phantoms, designed to provide a ground truth verification of the model predictions. The calculated and measured results were compared over a range of values for insonation pressure, insonation time, and flow rate; we show good agreement between predictions and measurements. We then conducted a series of simulations that address two limiting problems of interest: hemostasis in small and large vessels. We employed realistic human tissue properties and considered more complex geometries. Results show that the heating pattern in and around a blood vessel is different for different vessel sizes, flow rates and for varying beam orientations relative to the flow axis

  1. Multi-focus cluster labeling.

    PubMed

    Eikvil, Line; Jenssen, Tor-Kristian; Holden, Marit

    2015-06-01

    Document collections resulting from searches in the biomedical literature, for instance, in PubMed, are often so large that some organization of the returned information is necessary. Clustering is an efficient tool for organizing search results. To help the user to decide how to continue the search for relevant documents, the content of each cluster can be characterized by a set of representative keywords or cluster labels. As different users may have different interests, it can be desirable with solutions that make it possible to produce labels from a selection of different topical categories. We therefore introduce the concept of multi-focus cluster labeling to give users the possibility to get an overview of the contents through labels from multiple viewpoints. The concept for multi-focus cluster labeling has been established and has been demonstrated on three different document collections. We illustrate that multi-focus visualizations can give an overview of clusters along axes that general labels are not able to convey. The approach is generic and should be applicable to any biomedical (or other) domain with any selection of foci where appropriate focus vocabularies can be established. A user evaluation also indicates that such a multi-focus concept is useful.

  2. EDITORIAL: Focus on Gravitational Lensing

    NASA Astrophysics Data System (ADS)

    Jain, Bhuvnesh

    2007-11-01

    progressed rapidly. That cosmic shear is now regarded as a key element of major missions aimed at probing dark energy is a feat of scientific persuasion—a decade ago not many believed it was realistic to even detect this tiny shear signal, let alone measure it with the percent-level accuracy needed to advance dark energy measurements. If weak lensing measurements deliver on their promise, then, in combination with other imaging and spectroscopic probes, they may well impact fundamental physics and cosmology. For example they may find evidence for an evolving dark energy component or signatures of departures from general relativity. These exciting prospects rest on new optical surveys planned for the next five years which will image a thousand square degrees or more of the sky to redshifts ~1 (compared to about a hundred square degrees imaged currently). Further, through photometric redshifts based on galaxy colors, lensing tomography methods will be applied to learn about the three-dimensional distribution of dark matter. Lensing measurements in other wavelengths, such as planned 21-cm surveys and CMB lensing, would add valuable diversity to measurement techniques. The case for the next generation optical surveys from the ground and space is compelling as well: they will produce another order of magnitude in data quantity and deliver images with minimal distortions due to the atmosphere and telescope optics. The coming decade therefore has the potential for exciting discoveries in gravitational lensing. Focus on Gravitational Lensing Contents A Bayesian approach to strong lensing modelling of galaxy clusters E Jullo, J-P Kneib, M Limousin, Á Elíasdóttir, P J Marshall and T Verdugo Probing dark energy with cluster counts and cosmic shear power spectra: including the full covariance Masahiro Takada and Sarah Bridle How robust are the constraints on cosmology and galaxy evolution from the lens-redshift test? Pedro R Capelo and Priyamvada Natarajan Dark energy constraints

  3. Focusing on Pronouns: Consequences of Subjecthood, Pronominalisation, and Contrastive Focus

    ERIC Educational Resources Information Center

    Kaiser, Elsi

    2011-01-01

    We report two visual-world eye-tracking experiments that investigated the effects of subjecthood, pronominalisation, and contrastive focus on the interpretation of pronouns in subsequent discourse. By probing the effects of these factors on real-time pronoun interpretation, we aim to contribute to our understanding of how topicality-related…

  4. Magnetically focused liquid drop radiator

    DOEpatents

    Botts, Thomas E.; Powell, James R.; Lenard, Roger

    1986-01-01

    A magnetically focused liquid drop radiator for application in rejecting rgy from a spacecraft, characterized by a magnetizable liquid or slurry disposed in operative relationship within the liquid droplet generator and its fluid delivery system, in combination with magnetic means disposed in operative relationship around a liquid droplet collector of the LDR. The magnetic means are effective to focus streams of droplets directed from the generator toward the collector, thereby to assure that essentially all of the droplets are directed into the collector, even though some of the streams may be misdirected as they leave the generator. The magnetic focusing means is also effective to suppress splashing of liquid when the droplets impinge on the collector.

  5. Magnetically focused liquid drop radiator

    DOEpatents

    Botts, T.E.; Powell, J.R.; Lenard, R.

    1984-12-10

    A magnetically focused liquid drop radiator for application in rejecting energy from a spacecraft, characterized by a magnetizable liquid or slurry disposed in operative relationship within the liquid droplet generator and its fluid delivery system, in combination with magnetic means disposed in operative relationship around a liquid droplet collector of the LDR. The magnetic means are effective to focus streams of droplets directed from the generator toward the collector, thereby to assure that essentially all of the droplets are directed into the collector, even though some of the streams may be misdirected as they leave the generator. The magnetic focusing means is also effective to suppress splashing of liquid when the droplets impinge on the collector.

  6. EUV Focus Sensor: Design and Modeling

    SciTech Connect

    Goldberg, Kenneth A.; Teyssier, Maureen E.; Liddle, J. Alexander

    2005-05-01

    We describe performance modeling and design optimization of a prototype EUV focus sensor (FS) designed for use with existing 0.3-NA EUV projection-lithography tools. At 0.3-NA and 13.5-nm wavelength, the depth of focus shrinks to 150 nm increasing the importance of high-sensitivity focal-plane detection tools. The FS is a free-standing Ni grating structure that works in concert with a simple mask pattern of regular lines and spaces at constant pitch. The FS pitch matches that of the image-plane aerial-image intensity: it transmits the light with high efficiency when the grating is aligned with the aerial image laterally and longitudinally. Using a single-element photodetector, to detect the transmitted flux, the FS is scanned laterally and longitudinally so the plane of peak aerial-image contrast can be found. The design under consideration has a fixed image-plane pitch of 80-nm, with aperture widths of 12-40-nm (1-3 wavelengths), and aspect ratios of 2-8. TEMPEST-3D is used to model the light transmission. Careful attention is paid to the annular, partially coherent, unpolarized illumination and to the annular pupil of the Micro-Exposure Tool (MET) optics for which the FS is designed. The system design balances the opposing needs of high sensitivity and high throughput optimizing the signal-to-noise ratio in the measured intensity contrast.

  7. EUV focus sensor: design and modeling

    NASA Astrophysics Data System (ADS)

    Goldberg, Kenneth A.; Teyssier, Maureen E.; Liddle, J. Alexander

    2005-05-01

    We describe performance modeling and design optimization of a prototype EUV focus sensor (FS) designed for use with existing 0.3-NA EUV projection-lithography tools. At 0.3-NA and 13.5-nm wavelength, the depth of focus shrinks to 150 nm increasing the importance of high-sensitivity focal-plane detection tools. The FS is a free-standing Ni grating structure that works in concert with a simple mask pattern of regular lines and spaces at constant pitch. The FS pitch matches that of the image-plane aerial-image intensity: it transmits the light with high efficiency when the grating is aligned with the aerial image laterally and longitudinally. Using a single-element photodetector, to detect the transmitted flux, the FS is scanned laterally and longitudinally so the plane of peak aerial-image contrast can be found. The design under consideration has a fixed image-plane pitch of 80-nm, with aperture widths of 12-40-nm (1-3 wave-lengths), and aspect ratios of 2-8. TEMPEST-3D is used to model the light transmission. Careful attention is paid to the annular, partially coherent, unpolarized illumination and to the annular pupil of the Micro-Exposure Tool (MET) optics for which the FS is designed. The system design balances the opposing needs of high sensitivity and high throughput opti-mizing the signal-to-noise ratio in the measured intensity contrast.

  8. Staying in School. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1996

    1996-01-01

    This theme issue focuses on issues related to high Texas dropout rates among Hispanic and other minority group students and on dropout prevention strategies. "School Finance Inequities Mean Schools Are Not Ready To Teach" (Maria Robledo Montecel) deplores the recent Texas Supreme Court ruling that state educational funding is constitutional,…

  9. Technology for Education. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1998

    1998-01-01

    This theme issue includes five articles that focus on technology for education to benefit all students, including limited-English-proficient, minority, economically disadvantaged, and at-risk students. "Coca-Cola Valued Youth Program Students Meet Peers Via Video Conference" (Linda Cantu, Leticia Lopez-De La Garza) describes how at-risk student…

  10. Strategy and Focus: Teaching Literature.

    ERIC Educational Resources Information Center

    Karolides, Nicholas J., Ed.

    1983-01-01

    The six articles in this focused journal issue are concerned with literature teaching on the secondary and college level. The titles and authors of the articles are as follows: (1) "Aesthetic Reading and Teaching: 'Candide' Revisited" (Michael G. Gauthier); (2) "Discovery: The Role of Subjective Response in Initiating the Literature Discussion"…

  11. Math Fair: Focus on Fractions

    ERIC Educational Resources Information Center

    Mokashi, Neelima A.

    2009-01-01

    This article depicts the rewarding experience of creating mathematical environments for kindergarten and elementary students by focusing on one of the most important and often difficult-to-grasp concepts (fractions) through play methods incorporated into a math fair. The basic concept of a math fair is threefold: (1) to create preplanned,…

  12. World History. Focus on Economics.

    ERIC Educational Resources Information Center

    Caldwell, Jean; Clark, James; Herscher, Walter

    This book opens with an exploration of the first economic revolution, which set the stage for the dramatic unfolding of the role economics has played in world history. The lessons focus on two topics: (1) why some economies grew and prospered while others remained stagnant or declined; and (2) what causes people to make choices that help or hinder…

  13. Focused X-ray source

    DOEpatents

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Maccagno, P.

    1990-08-21

    Disclosed is an intense, relatively inexpensive X-ray source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator. 8 figs.

  14. Evaluating Pragmatics-Focused Materials

    ERIC Educational Resources Information Center

    Crandall, Elizabeth; Basturkmen, Helen

    2004-01-01

    Learners often find the area of pragmatics (that is, using speech acts such as requesting, inviting, and complimenting) problematic. Teachers are urged to teach pragmatic aspects of language, and make use of authentic samples of spoken discourse to do so. However, information about the effectiveness of pragmatics-focused instruction of this nature…

  15. Standards and Assessment. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1997

    1997-01-01

    This newsletter includes three articles, two of which focus on standards for student evaluation and for admission to higher education. "A Measuring Stick for Standards and TEKS: Meeting the Needs of Second Language Learners" (Laura Chris Green, Adela Solis) examines beliefs embodied in the notion of standards; defines content, performance, and…

  16. Zoonotic Focus of Plague, Algeria

    PubMed Central

    Bitam, Idir; Baziz, Belkacem; Rolain, Jean-Marc; Belkaid, Miloud

    2006-01-01

    After an outbreak of human plague, 95 Xenopsylla cheopis fleas from Algeria were tested for Yersinia pestis with PCR methods. Nine fleas were definitively confirmed to be infected with Y. pestis biovar orientalis. Our results demonstrate the persistence of a zoonotic focus of Y. pestis in Algeria. PMID:17326957

  17. The Ionospheric Focused Heating experiment

    NASA Astrophysics Data System (ADS)

    Bernhardt, P. A.; Siefring, C. L.; Rodriguez, P.; Haas, D. G.; Baumback, M. M.; Romero, H. A.; Solin, D. A.; Djuth, F. T.; Duncan, L. M.; Hunton, D. E.; Pollock, C. J.; Sulzer, M. P.; Tepley, C. A.; Wagner, L. S.; Goldstein, J. A.

    1995-09-01

    The Ionospheric Focused Heating rocket was launched on May 30, 1992. The sounding rocket carried an instrument and chemical payload along a trajectory that crossed the intersection of the beams from the 430-MHz incoherent scatter radar and the 5.1-MHz high-power radio wave facility near Arecibo. The release of 30 kg of CF3Br into the F region at 285 km altitude produced an ionospheric hole that acted like a convergent lens to focus the HF transmissions. The power density inside the radio beam was raised by 12 dB immediately after the release. A wide range of new processes were recorded by in situ and ground-based instruments. Measurements by instruments flying through the modified ionosphere show small-scale microcavities (<1 m) and downshifted electron plasma (Langmuir) waves inside the artificial cavity, electron density spikes at the edge of the cavity, and Langmuir waves coincident with ion gyroradius (4 m) cavities near the radio wave reflection altitude. The Arecibo incoherent scatter radar showed 20 dB or greater enhancements in ion acoustic and Langmuir wave turbulence after the 5.1-MHz radio beam was focused by the artificial lens. Enhancements in airglow from chemical reactions and, possibly, electron acceleration were recorded with optical instruments. The Ionospheric Focused Heating experiment verified some of the preflight predictions and demonstrated the value of active experiments that combine high-power radio waves with chemical releases.

  18. Focused X-ray source

    DOEpatents

    Piestrup, Melvin A.; Boyers, David G.; Pincus, Cary I.; Maccagno, Pierre

    1990-01-01

    An intense, relatively inexpensive X-ray source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator.

  19. Work and Family. Special Focus.

    ERIC Educational Resources Information Center

    Goetz, Kathy, Ed.

    1992-01-01

    This newsletter issue focuses on issues concerning families with both parents employed outside the home and describes several employer programs designed to help employees balance their work and family life. The newsletter includes the following articles: (1) "Work and Family: 1992"; (2) "Levi Strauss and Co.--A Work/Family Program in Action"; (3)…

  20. Focus on Young Adult Programming.

    ERIC Educational Resources Information Center

    Union, Bunni; Williams, Sheila

    1996-01-01

    Presents three library youth service programs which focus on "Pizza and Politicians," a public library pizza party which gave high school students and college-aged young adults a chance to meet and question politicians; a young adult "Reading to Seniors" program; "Making Books," a public library journal-making project for middle school students.…

  1. Supporting Task-Focused Communication.

    ERIC Educational Resources Information Center

    Lipinski, Hubert; And Others

    The extension of computer based communication to the more task-focused communication required by groups involved in joint problem solving is discussed in this paper. Specifically, it addresses three areas: (1) the aspects of the joint problem solving that are most suited to computer based communication support, (2) the computer based communication…

  2. Teaching and Learning. IDRA Focus.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1997

    1997-01-01

    This theme issue includes four articles that focus on teaching and learning strategies to benefit all students, including limited-English-proficient, minority, economically disadvantaged, and at-risk students. "Would You Read Me a Story?: In Search of Reading Strategies That Work for the Early Childhood Classroom" (Hilaria Bauer) discusses how…

  3. Focused ion beams in biology.

    PubMed

    Narayan, Kedar; Subramaniam, Sriram

    2015-11-01

    A quiet revolution is under way in technologies used for nanoscale cellular imaging. Focused ion beams, previously restricted to the materials sciences and semiconductor fields, are rapidly becoming powerful tools for ultrastructural imaging of biological samples. Cell and tissue architecture, as preserved in plastic-embedded resin or in plunge-frozen form, can be investigated in three dimensions by scanning electron microscopy imaging of freshly created surfaces that result from the progressive removal of material using a focused ion beam. The focused ion beam can also be used as a sculpting tool to create specific specimen shapes such as lamellae or needles that can be analyzed further by transmission electron microscopy or by methods that probe chemical composition. Here we provide an in-depth primer to the application of focused ion beams in biology, including a guide to the practical aspects of using the technology, as well as selected examples of its contribution to the generation of new insights into subcellular architecture and mechanisms underlying host-pathogen interactions.

  4. Law-Focused Education: Iowa.

    ERIC Educational Resources Information Center

    University of Northern Iowa, Cedar Falls. Malcolm Price Lab. School.

    This law-focused resource booklet is intended to help secondary level students learn about the civil law portion of Iowa's judicial system. The materials are designed to help students understand how to deal with conflict in a peaceful and orderly manner and how to cope with decision making in personal law situations as related to the family, the…

  5. FOREWORD: Focus on Advanced Ceramics Focus on Advanced Ceramics

    NASA Astrophysics Data System (ADS)

    Ohashi, Naoki

    2011-06-01

    Much research has been devoted recently to developing technologies for renewable energy and improving the efficiency of the processes and devices used in industry and everyday life. Efficient solutions have been found using novel materials such as platinum and palladium-based catalysts for car exhaust systems, samarium-cobalt and neodymium-iron-boron permanent magnets for electrical motors, and so on. However, their realization has resulted in an increasing demand for rare elements and in their deficit, the development of new materials based on more abundant elements and new functionalities of traditional materials. Moreover, increasing environmental and health concerns demand substitution of toxic or hazardous substances with nature-friendly alternatives. In this context, this focus issue on advanced ceramics aims to review current trends in ceramics science and technology. It is related to the International Conference on Science and Technology of Advanced Ceramics (STAC) held annually to discuss the emerging issues in the field of ceramics. An important direction of ceramic science is the collaboration between experimental and theoretical sciences. Recent developments in density functional theory and computer technology have enabled the prediction of physical and chemical properties of ceramics, thereby assisting the design of new materials. Therefore, this focus issue includes articles devoted to theory and advanced characterization techniques. As mentioned above, the potential shortage of rare elements is becoming critical to the industry and has resulted in a Japanese government initiative called the 'Ubiquitous Element Strategy'. This focus issue also includes articles related to this strategy and to the associated topics of energy conversion, such as phosphors for high-efficiency lighting and photocatalysts for solar-energy harvesting. We hope that this focus issue will provide a timely overview of current trends and problems in ceramics science and

  6. EDITORIAL: Focus on terahertz plasmonics

    NASA Astrophysics Data System (ADS)

    Rahm, Marco; Nahata, Ajay; Akalin, Tahsin; Beruete, Miguel; Sorolla, Mario

    2015-10-01

    Plasmonics is one of the growing fields in modern photonics that has garnered increasing interest over the last few years. In this focus issue, the specific challenges concerning terahertz plasmonics have been addressed and most recent advances in this specific field have been highlighted. The articles demonstrate the diversity and the opportunities of this rich field by covering a variety of topics ranging from the propagation of surface plasmon polaritons (SPPs) on artificially structures surfaces, 2D manipulation of surface plasmons and SPPs, plasmonic focusing, plasmonic high-Q resonators for sensing applications, plasmonically enhanced terahertz antennas to terahertz field manipulation by use of plasmonic structures. The articles substantiate the impact of plasmonics and its great innovative potential for terahertz technology. In memory of Professor Mario Sorolla Ayza.

  7. Development of an immunofluorescence focus assay for Ebola virus.

    PubMed Central

    Truant, A L; Regnery, R L; Kiley, M P

    1983-01-01

    A 48-h indirect immunofluorescence focus assay for the quantitation of Ebola virus was developed, utilizing HeLa-229 cell monolayers. The dose dependency and the sensitivity of this assay as compared with conventional assays are reported. This indirect immunofluorescence focus assay can be used as a rapid, quantitative test for the detection of Ebola virus, an agent from Africa known to cause hemorrhagic fever. Images PMID:6352735

  8. Focused electron beam in pyroelectric electron probe microanalyzer

    SciTech Connect

    Imashuku, Susumu; Imanishi, Akira; Kawai, Jun

    2013-07-15

    We report a method to focus the electron beam generated using a pyroelectric crystal. An electron beam with a spot size of 100 μm was achieved by applying an electrical field to an electroconductive needle tip set on a pyroelectric crystal. When the focused electron beam bombarded a sample, characteristic X-rays of the sample were only detected due to the production of an electric field between the needle tip and the sample.

  9. The quest for customer focus.

    PubMed

    Gulati, Ranjay; Oldroyd, James B

    2005-04-01

    Companies have poured enormous amounts of money into customer relationship management, but in many cases the investment hasn't really paid off. That's because getting closer to customers isn't about building an information technology system. It's a learning journey-one that unfolds over four stages, requiring people and business units to coordinate in progressively more sophisticated ways. The journey begins with the creation of a companywide repository containing each interaction a customer has with the company, organized not by product, purchase, or location, but by customer. Communal coordination is what's called for at this stage, as each group contributes its information to the data pool separately from the others and then taps into it as needed. In the second stage, one-way serial coordination from centralized IT through analytical units and out to the operating units allows companies to go beyond just assembling data to drawing inferences. In stage three, companies shift their focus from past relationships to future behavior. Through symbiotic coordination, information flows back and forth between central analytic units and various organizational units like marketing, sales, and operations, as together they seek answers to questions like "How can we prevent customers from switching to a competitor?" and "Who would be most likely to buy a new product in the future"? In stage four, firms begin to move past discrete, formal initiatives and, through integral coordination, bring an increasingly sophisticated understanding oftheir customers to bear in all day-to-day operations. Skipping stages denies organizations the sure foundation they need to build a lasting customer-focused mind-set. Those that recognize this will invest their customer relationship dollars much more wisely-and will see their customer-focusing efforts pay offon the bottom line. PMID:15807042

  10. Tanks focus area. Annual report

    SciTech Connect

    Frey, J.

    1997-12-31

    The U.S. Department of Energy Office of Environmental Management is tasked with a major remediation project to treat and dispose of radioactive waste in hundreds of underground storage tanks. These tanks contain about 90,000,000 gallons of high-level and transuranic wastes. We have 68 known or assumed leaking tanks, that have allowed waste to migrate into the soil surrounding the tank. In some cases, the tank contents have reacted to form flammable gases, introducing additional safety risks. These tanks must be maintained in the safest possible condition until their eventual remediation to reduce the risk of waste migration and exposure to workers, the public, and the environment. Science and technology development for safer, more efficient, and cost-effective waste treatment methods will speed up progress toward the final remediation of these tanks. The DOE Office of Environmental Management established the Tanks Focus Area to serve as the DOE-EM`s technology development program for radioactive waste tank remediation in partnership with the Offices of Waste Management and Environmental Restoration. The Tanks Focus Area is responsible for leading, coordinating, and facilitating science and technology development to support remediation at DOE`s four major tank sites: the Hanford Site in Washington State, Idaho National Engineering and Environmental Laboratory in Idaho, Oak Ridge Reservation in Tennessee, and the Savannah River Site in South Carolina. The technical scope covers the major functions that comprise a complete tank remediation system: waste retrieval, waste pretreatment, waste immobilization, tank closure, and characterization of both the waste and tank. Safety is integrated across all the functions and is a key component of the Tanks Focus Area program.

  11. Final focus system for TLC

    SciTech Connect

    Oide, K.

    1988-11-01

    A limit of the chromaticity correction for the final focus system of a TeV Linear Collider (TLC) is investigated. As the result, it becomes possible to increase the aperture of the final doublet with a small increase of the horizontal US function. The new optics design uses a final doublet of 0.5 mm half-aperture and 1.4 T pole-tip field. The length of the system is reduced from 400 m to 200 m by several optics changes. Tolerances for various machine errors with this optics are also studied. 5 refs., 7 figs., 2 tabs.

  12. [Fulguration of extrasystolic ventricular focus].

    PubMed

    Velázquez Rodríguez, E; Rosas, F; Frank, R; Fontaine, G; Tonet, J; Lascault, G; Gallais, Y

    1995-01-01

    A case is presented of symptomatic premature ventricular contractions refractory to drug therapy with right bundle branch block QRS morphology and left axis deviation in a 68-year-old female without structural heart disease. Endocardial mapping localized the extrasystolic focus at meso-inferoapical region of the left ventricular septum suggesting an origin from the Purkinje network of the left posterior fascicle. Catheter ablation with direct-current energy abolished extrasystolic complexes, without complications. The patient remained asymptomatic over a follow-up of 3 months. PMID:7543744

  13. A focus on human flourishing.

    PubMed

    Bunkers, Sandra Schmidt

    2010-10-01

    In this column the author focuses on the concepts of human vulnerability and human flourishing. A parable is presented highlighting the importance of now, the present, in human flourishing. A bioethical, anthropological perspective and a nursing humanbecoming perspective on human flourishing are offered. Nursing education is challenged to emphasize the nursing theories of the discipline to teach the concept of human flourishing. Parse's concept of true presence, the four postulates of humanbecoming, and the humanbecoming community change concepts illuminate a nursing theoretical understanding of human flourishing. PMID:20870999

  14. Line-focus sun trackers

    SciTech Connect

    Gee, R.

    1980-05-01

    Sun trackers have been a troublesome component for line-focus concentrating collector systems. The problems have included poor accuracy, component failures, false locks on clouds, and restricted tracker operating ranges. In response to these tracking difficulties, a variety of improved sun trackers have been developed. A testing program is underway at SERI to determine the tracking accuracy of this new generation of sun trackers. The three major types of trackers are defined, some recent sun tracker developments are described, and the testing that is underway is outlined.

  15. A focused bibliography on robotics

    NASA Astrophysics Data System (ADS)

    Mergler, H. W.

    1983-08-01

    The present bibliography focuses on eight robotics-related topics believed by the author to be of special interest to researchers in the field of industrial electronics: robots, sensors, kinematics, dynamics, control systems, actuators, vision, economics, and robot applications. This literature search was conducted through the 1970-present COMPENDEX data base, which provides world-wide coverage of nearly 3500 journals, conference proceedings and reports, and the 1969-1981 INSPEC data base, which is the largest for the English language in the fields of physics, electrotechnology, computers, and control.

  16. Isoelectric focusing of urinary metallothionein.

    PubMed

    Felley-Bosco, E; Hunziker, P E; Savolainen, H

    1990-05-01

    Isoelectric focusing of human urinary metallothionein at a pH range of 4.8 to 7.0 yielded a single protein band with a pI of 5.57 which co-migrated with authentic purified metallothionein I from human liver. Minimum pretreatment of the urine samples (160 ml) was needed. The preparatory steps included sample concentration with the original protein, enriched from 69 +/- 23 micrograms/ml to 2.0 +/- 1.4 mg/ml (+/- SD; n = 9), followed by heat treatment at 80 degrees C for 5 min (2.4 +/- 1.7 mg protein/ml). After focusing, the gels were stained with silver and the lanes were scanned with a laser scanner. Peak areas were used for quantitation with commercial beta 2-microglobulin as a standard. The urinary metallothionein ranged from 1.0 to 2.6 nmol/mmol creatinine, which is comparable with values reached by radio-immunoassay.

  17. Plutonium focus area. Technology summary

    SciTech Connect

    1997-09-01

    The Assistant Secretary for the Office of Environmental Management (EM) at the U.S. Department of Energy (DOE) chartered the Plutonium Focus Area (PFA) in October 1995. The PFA {open_quotes}...provides for peer and technical reviews of research and development in plutonium stabilization activities...{close_quotes} In addition, the PFA identifies and develops relevant research and technology. The purpose of this document is to focus attention on the requirements used to develop research and technology for stabilization, storage, and preparation for disposition of nuclear materials. The PFA Technology Summary presents the approach the PFA uses to identify, recommend, and review research. It lists research requirements, research being conducted, and gaps where research is needed. It also summarizes research performed by the PFA in the traditional research summary format. This document encourages researchers and commercial enterprises to do business with PFA by submitting research proposals or {open_quotes}white papers.{close_quotes} In addition, it suggests ways to increase the likelihood that PFA will recommend proposed research to the Nuclear Materials Stabilization Task Group (NMSTG) of DOE.

  18. Development of a Focusing DIRC

    SciTech Connect

    Benitez, J.; Bedajanek, I.; Leith, D.W.G.S.; Mazaheri, G.; Ratcliff, B.; Suzuki, K.; Schwiening, J.; Uher, J.; Va'vra, J.; /SLAC

    2006-12-12

    Benefiting from the recent introduction of new fast vacuum-based photon detectors with a transit time spread of {sigma}{sub TTS} {approx} 30-150 ps, we are developing a novel RICH detector capable of correcting the chromatic error through good time measurements; we believe that this is the first time such a technique has been demonstrated. We have built and successfully tested a particle identification detector called ''Focusing DIRC''. The concept of the prototype is based on the BaBar DIRC, with several important improvements: (a) much faster pixelated photon detectors based on Burle MCP-PMTs and Hamamatsu MaPMTs, (b) a focusing mirror which allows the photon detector to be smaller and less sensitive to background in future applications, (c) electronics allowing the measurement of single photon timing to better than {sigma} {approx} 100-200ps, which allows a correction of the chromatic error. The detector was tested in a SLAC 10GeV/c electron test beam. This detector concept could be used for particle identification at Super B-factory, ILC, GlueX, Panda, etc.

  19. Focus on the Rashba effect

    NASA Astrophysics Data System (ADS)

    Bihlmayer, G.; Rader, O.; Winkler, R.

    2015-05-01

    The Rashba effect, discovered in 1959, continues to supply fertile ground for fundamental research and applications. It provided the basis for the proposal of the spin transistor by Datta and Das in 1990, which has largely inspired the broad and dynamic field of spintronics. More recent developments include new materials for the Rashba effect such as metal surfaces, interfaces and bulk materials. It has also given rise to new phenomena such as spin currents and the spin Hall effect, including its quantized version, which has led to the very active field of topological insulators. The Rashba effect plays a crucial role in yet more exotic fields of physics such as the search for Majorana fermions at semiconductor-superconductor interfaces and the interaction of ultracold atomic Bose and Fermi gases. Advances in our understanding of Rashba-type spin-orbit couplings, both qualitatively and quantitatively, can be obtained in many different ways. This focus issue brings together the wide range of research activities on Rashba physics to further promote the development of our physical pictures and concepts in this field. The present Editorial gives a brief account on the history of the Rashba effect including material that was previously not easily accessible before summarizing the key results of the present focus issue as a guidance to the reader.

  20. Future focus for professional development.

    PubMed

    Roberts, Nicole K; Coplit, Lisa D

    2013-01-01

    Professional development has evolved from individually focused sabbaticals and professional leaves to institutionally focused programs with an interest in developing faculty members' ability to teach in various environments as well as to succeed in the many endeavors they undertake. We address various issues related to professional development in the medical school arena. Professional development in medical school takes place in a context where faculty are stretched to engage in research and service not only for their own sake but also to financially support their institutions. This obligates professional developers to acknowledge and address the environments in which teaching faculty work, and to use approaches to professional development that honor the time and efforts of teaching faculty. These approaches may be brief interventions that make use of principles of education, and may include online offerings. Professional development will be most effective when professional developers acknowledge that most faculty members aspire to excellence in teaching, but they do so in an environment that pushes them to address competing concerns. Offering professional development opportunities that fit within the workplace environment, take little time, and build upon faculty's existing knowledge will assist in enhancing faculty success.

  1. Targeted therapy using nanotechnology: focus on cancer

    PubMed Central

    Sanna, Vanna; Pala, Nicolino; Sechi, Mario

    2014-01-01

    Recent advances in nanotechnology and biotechnology have contributed to the development of engineered nanoscale materials as innovative prototypes to be used for biomedical applications and optimized therapy. Due to their unique features, including a large surface area, structural properties, and a long circulation time in blood compared with small molecules, a plethora of nanomaterials has been developed, with the potential to revolutionize the diagnosis and treatment of several diseases, in particular by improving the sensitivity and recognition ability of imaging contrast agents and by selectively directing bioactive agents to biological targets. Focusing on cancer, promising nanoprototypes have been designed to overcome the lack of specificity of conventional chemotherapeutic agents, as well as for early detection of precancerous and malignant lesions. However, several obstacles, including difficulty in achieving the optimal combination of physicochemical parameters for tumor targeting, evading particle clearance mechanisms, and controlling drug release, prevent the translation of nanomedicines into therapy. In spite of this, recent efforts have been focused on developing functionalized nanoparticles for delivery of therapeutic agents to specific molecular targets overexpressed on different cancer cells. In particular, the combination of targeted and controlled-release polymer nanotechnologies has resulted in a new programmable nanotherapeutic formulation of docetaxel, namely BIND-014, which recently entered Phase II clinical testing for patients with solid tumors. BIND-014 has been developed to overcome the limitations facing delivery of nanoparticles to many neoplasms, and represents a validated example of targeted nanosystems with the optimal biophysicochemical properties needed for successful tumor eradication. PMID:24531078

  2. Focusing ecological research for conservation.

    PubMed

    Cristescu, Bogdan; Boyce, Mark S

    2013-11-01

    Ecologists are increasingly actively involved in conservation. We identify five key topics from a broad sweep of ecology that merit research attention to meet conservation needs. We examine questions from landscape ecology, behavioral ecology, ecosystem dynamics, community ecology, and nutrient cycling related to key topics. Based on literature review and publication trend assessment, consultation with colleagues, and roundtable discussions at the 24th International Congress for Conservation Biology, focused research on the following topics could benefit conservation while advancing ecological understanding: 1. Carbon sequestration, requiring increased linkages to biodiversity conservation; 2. Ecological invasiveness, challenging our ability to find solutions to ecological aliens; 3. Individual variation, having applications in the conservation of rare species; 4. Movement of organisms, integrating ecological processes across landscapes and scales and addressing habitat fragmentation; and 5. Trophic-level interactions, driving ecological dynamics at the ecosystem-level. Addressing these will require cross-disciplinary research under the overarching framework of conservation ecology.

  3. Focus on Basal Cell Carcinoma

    PubMed Central

    Samarasinghe, Venura; Madan, Vishal; Lear, John T.

    2011-01-01

    Nonmelanoma skin cancers (NMSCs), which include basal and squamous cell cancers are the most common human cancers. BCCs have a relatively low metastatic rate and slow growth and are frequently underreported. Whilst there is a definite role of sunexposure in the pathogenesis of BCC, several additional complex genotypic, phenotypic and environmental factors are contributory. The high prevalence and the frequent occurrence of multiple primary BCC in affected individuals make them an important public health problem. This has led to a substantial increase in search for newer noninvasive treatments for BCC. Surgical excision with predetermined margins remains the mainstay treatment for most BCC. Of the newer non-invasive treatments only photodynamic therapy and topical imiquimod have become established in the treatment of certain BCC subtypes, while the search for other more effective and tissue salvaging therapies continues. This paper focuses on the pathogenesis and management of BCC. PMID:21152128

  4. Focusing X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    O'Dell, Stephen; Brissenden, Roger; Davis, William; Elsner, Ronald; Elvis, Martin; Freeman, Mark; Gaetz, Terrance; Gorenstein, Paul; Gubarev, Mikhall; Jerlus, Diab; Juda, Michael; Kolodziejczak, Jeffrey; Murray, Stephen; Petre, Robert; Podgorski, William; Ramsey, Brian; Reid, Paul; Saha, Timo; Wolk, Scott; Troller-McKinstry, Susan; Weisskopf, Martin; Wilke, Rudeger; Zhang, William

    2010-01-01

    During the half-century history of x-ray astronomy, focusing x-ray telescopes, through increased effective area and finer angular resolution, have improved sensitivity by 8 orders of magnitude. Here, we review previous and current x-ray-telescope missions. Next, we describe the planned next-generation x-ray-astronomy facility, the International X-ray Observatory (IXO). We conclude with an overview of a concept for the next next-generation facility, Generation X. Its scientific objectives will require very large areas (about 10,000 sq m) of highly-nested, lightweight grazing-incidence mirrors, with exceptional (about 0.1-arcsec) resolution. Achieving this angular resolution with lightweight mirrors will likely require on-orbit adjustment of alignment and figure.

  5. Micron-focused ion beamlets

    NASA Astrophysics Data System (ADS)

    Chowdhury, Abhishek; Bhattacharjee, Sudeep

    2010-05-01

    A multiple beam electrode system (MBES) is used to provide focused ion beamlets of elements from a compact microwave plasma. In this study, a honeycomb patterned plasma electrode with micron size apertures for extracting ion beamlets is investigated. The performance of the MBES is evaluated with the help of two widely adopted and commercially available beam simulation tools, AXCEL-INP and SIMION, where the input parameters are obtained from our experiments. A simple theoretical model based upon electrostatic ray optics is employed to compare the results of the simulations. It is found that the results for the beam focal length agree reasonably well. Different geometries are used to optimize the beam spot size and a beam spot ˜5-10 μm is obtained. The multiple ion beamlets will be used to produce microfunctional surfaces on soft matter like polymers. Additionally, the experimental set-up and plans are presented in the light of above applications.

  6. NASA Budget Focuses on Exploration

    NASA Astrophysics Data System (ADS)

    Zielinski, Sarah

    2006-02-01

    NASA has decided to rebalance its priorities following several years of healthy growth for science, turning its focus instead towards expanding support for manned space exploration, explained NASA Administrator Michael Griffin at a 16 February hearing before the U.S. House of Representatives Committee on Science. The Bush Administration has requested $16.8 billion for NASA in Fiscal Year 2007, an increase of 3.2 percent over the previous year. Most of the benefit would go to the exploration program, which would get a 55 percent increase in funding-for a total of $3.9 billion-primarily for the development of the new Crew Exploration Vehicle and Crew Launch Vehicle. The science budget would grow by 1.5 percent in FY2007-to $5.3 billion-and then is projected to grow by just one percent per year in 2008-2011.

  7. Focus: Asian migration to Canada.

    PubMed

    Kobayashi, A

    1988-01-01

    This collection of 5 short essays on Asian migration to Canada focuses on the relationships between individual migrants and their social contexts, both Asian and Canadian. Papers by Anderson and Kobayashi adopt research perspectives of outsider and insider, respectively. Vibert provides a historical overview against which the substantive issues introduced in the other 3 papers can be understood, and he illustrates the links between circumstances of migration and the larger issues by which the course of Canadian social progress has been steered. Mercer provides an introduction to issues that dominate the agenda of contemporary research, to show that Canadian communities of Asian heritage continue to grow in size, diversity, and complexity, as they become more established on the Canadian landscape. This collection is as much about the geography of racism as it is about migration.

  8. Tank Focus Area pretreatment activities

    SciTech Connect

    McGinnis, C.P.; Welch, T.D.; Manke, K.L.

    1997-03-01

    Plans call for the high-level wastes to be retrieved from the tanks and immobilized in a stable waste form suitable for long-term isolation. Chemistry and chemical engineering operations are required to retrieve the wastes, to condition the wastes for subsequent steps, and to reduce the costs of the waste management enterprise. Pretreatment includes those processes between retrieval and immobilization, and includes preparation of suitable feed material for immobilization and separations to partition the waste into streams that yield lower life-cycle costs. Some of the technologies being developed by the Tank Focus Area (TFA) to process these wastes are described. These technologies fall roughly into three areas: (1) solid/liquid separation (SLS), (2) sludge pretreatment, and (3) supernate pretreatment.

  9. Hormone Purification by Isoelectric Focusing

    NASA Technical Reports Server (NTRS)

    Bier, M.

    1985-01-01

    Various ground-based research approaches are being applied to a more definitive evaluation of the natures and degrees of electroosmosis effects on the separation capabilities of the Isoelectric Focusing (IEF) process. A primary instrumental system for this work involves rotationally stabilized, horizontal electrophoretic columns specially adapted for the IEF process. Representative adaptations include segmentation, baffles/screens, and surface coatings. Comparative performance and development testing are pursued against the type of column or cell established as an engineering model. Previously developed computer simulation capabilities are used to predict low-gravity behavior patterns and performance for IEF apparatus geometries of direct project interest. Three existing mathematical models plus potential new routines for particular aspects of simulating instrument fluid patterns with varied wall electroosmosis influences are being exercised.

  10. Rotating Apparatus for Isoelectric Focusing

    NASA Technical Reports Server (NTRS)

    Bier, M.

    1986-01-01

    Remixing of separated fractions prevented. Improved isoelectric focusing apparatus helps to prevent electro-osmosis and convection, both of which cause remixing of separated fractions. Fractionating column segmented and rotated about horizontal axis: Only combined effects of both features fully effective in making good separations. Improved apparatus slowly rotated continuously or rocked (at rotational amplitude of at least 180 degrees) about its horizontal axis so average gravitational vector experienced by fluid is zero and convection is therefore suppressed. Electro-osmosis suppressed and convection further suppressed by separating column into disklike compartments along its length with filters. Experiments have shown dimensions of apparatus not critical. Typical compartment and column volumes are 2 and 40 ml, respectively. Rotation speeds lie between 3 and 30 rpm.

  11. Signal focusing through active transport.

    PubMed

    Godec, Aljaž; Metzler, Ralf

    2015-07-01

    The accuracy of molecular signaling in biological cells and novel diagnostic devices is ultimately limited by the counting noise floor imposed by the thermal diffusion. Motivated by the fact that messenger RNA and vesicle-engulfed signaling molecules transiently bind to molecular motors and are actively transported in biological cells, we show here that the random active delivery of signaling particles to within a typical diffusion distance to the receptor generically reduces the correlation time of the counting noise. Considering a variety of signaling particle sizes from mRNA to vesicles and cell sizes from prokaryotic to eukaryotic cells, we show that the conditions for active focusing-faster and more precise signaling-are indeed compatible with observations in living cells. Our results improve the understanding of molecular cellular signaling and novel diagnostic devices.

  12. Subcycle Pulsed Focused Vector Beams

    SciTech Connect

    Lin Qiang; Zheng Jian; Becker, Wilhelm

    2006-12-22

    An accurate description of a subcycle pulsed beam (SCPB) is presented based on the complex-source model. The fields are exact solutions of Maxwell's equations and applicable to a focused pulsed beam with a pulse duration down to and below one cycle of the carrier wave and with arbitrary polarization state. Depending on the pulse duration, the pulse is blueshifted, and its wings are chirped. This effect, which we refer to as 'self-induced blueshift' goes beyond the carrier-envelope description. The corresponding phase is a temporal analog of the Gouy phase. The energy gain of a relativistic electron swept over by an SCPB is very sensitive to the proper form chosen to describe the pulse.

  13. Centripetal focusing of gyrotactic phytoplankton.

    PubMed

    Cencini, M; Franchino, M; Santamaria, F; Boffetta, G

    2016-06-21

    A suspension of gyrotactic microalgae Chlamydomonas augustae swimming in a cylindrical water vessel in solid-body rotation is studied. Our experiments show that swimming algae form an aggregate around the axis of rotation, whose intensity increases with the rotation speed. We explain this phenomenon by the centripetal orientation of the swimming direction towards the axis of rotation. This centripetal focusing is contrasted by diffusive fluxes due to stochastic reorientation of the cells. The competition of the two effects lead to a stationary distribution, which we analytically derive from a refined mathematical model of gyrotactic swimmers. The temporal evolution of the cell distribution, obtained via numerical simulations of the stochastic model, is in quantitative agreement with the experimental measurements in the range of parameters explored. PMID:27060672

  14. Non-focusing active warhead

    DOEpatents

    Hornig, Howard C.

    1998-01-01

    A non-nuclear, non-focusing, active warhead that comprises a high explosive charge contained within a casing of reactive metal. When the high explosive is detonated, the reactive metal is dispersed and reacts with the air, which significantly increases the explosive yield of the warhead. The active warhead produces therefore much higher blast effects with significantly reduced weight compared to conventional munitions. The warhead is highly effective against such targets as aircraft which typically have thin fuselages, for example. The explosiveness of this warhead can be enhanced further by elevating the temperature and therefore the reactivity of the reactive metal before or during the explosion. New methods of enhancing the reactivity of the metal are also taught.

  15. Non-focusing active warhead

    DOEpatents

    Hornig, H.C.

    1998-12-22

    A non-nuclear, non-focusing, active warhead that comprises a high explosive charge contained within a casing of reactive metal is disclosed. When the high explosive is detonated, the reactive metal is dispersed and reacts with the air, which significantly increases the explosive yield of the warhead. The active warhead produces therefore much higher blast effects with significantly reduced weight compared to conventional munitions. The warhead is highly effective against such targets as aircraft which typically have thin fuselages, for example. The explosiveness of this warhead can be enhanced further by elevating the temperature and therefore the reactivity of the reactive metal before or during the explosion. New methods of enhancing the reactivity of the metal are also taught. 4 figs.

  16. Focused rigidity casts: an overview.

    PubMed

    Dagg, A R; Chockalingam, N; Branthwaite, H

    2013-02-01

    Focused rigidity casts (FRCs) are a novel treatment made from polymer semi-flexible cast material, used in the management of plantar foot ulceration to offload the site of ulceration. Current anecdotal evidence suggests that use of FRCs helps achieve quicker healing time. While FRCs were first used in the treatment of fractures, previous reports suggest that the FRC may be effective in the treatment of plantar foot ulceration. Although there is a paucity of evidence to support the use of FRCs in the treatment of foot ulceration, current evidence demonstrates a decrease in both wound healing time and plantar pressure. The aim of the paper is to examine the importance of offloading plantar ulcerations and introduce FRCs.

  17. Variable focus crystal diffraction lens

    SciTech Connect

    Smither, R.K.

    1988-11-01

    A new method has been developed to control the shape of the surface of a diffracting crystal that will allow it to function as a variable focus crystal diffraction lens, for focusing photon beams from a synchrotron source. The new method uses thermal gradients in the crystal to control the shape of the surface of the crystal in two dimensions and allows one to generate both spherical and ellipsoidal surface shapes. In this work the thermal gradient was generated by core drilling two sets of cooling channels in a silicon crystal so that cooling or heating fluids could be circulated through the crystal at two different levels. The first set of channels is close to the surface of the crystal where the photon beam strikes it. The second set of channels is equal distant from the back surface. If a concave surface is desired, the fluid in the channels just below the surface exposed to the beam is cooler than the fluid circulating through the channels near the back surface. If a convex surface is desired, then the cooling fluid in the upper channels near the surface exposed to the incident photon beam, is warmer than the fluid in the lower channels. The focal length of the crystal lens is varied by varying the thermal gradient in the crystal. This approach can also be applied to the first crystal in a high power synchrotron beam line to eliminate the bowing and other thermal distortions of the crystal caused by the high heat load. 6 refs., 8 figs., 3 tabs.

  18. EDITORIAL: Focus on Cloud Physics FOCUS ON CLOUD PHYSICS

    NASA Astrophysics Data System (ADS)

    Falkovich, Gregory; Malinowski, Szymon P.

    2008-07-01

    Cloud physics has for a long time been an important segment of atmospheric science. It is common knowledge that clouds are crucial for our understanding of weather and climate. Clouds are also interesting by themselves (not to mention that they are beautiful). Complexity is hidden behind the common picture of these beautiful and interesting objects. The typical school textbook definition that a cloud is 'a set of droplets or particles suspended in the atmosphere' is not adequate. Clouds are complicated phenomena in which dynamics, turbulence, microphysics, thermodynamics and radiative transfer interact on a wide range of scales, from sub-micron to kilometres. Some of these interactions are subtle and others are more straightforward. Large and small-scale motions lead to activation of cloud condensation nuclei, condensational growth and collisions; small changes in composition and concentration of atmospheric aerosol lead to significant differences in radiative properties of the clouds and influence rainfall formation. It is justified to look at a cloud as a composite, nonlinear system which involves many interactions and feedback. This system is actively linked into a web of atmospheric, oceanic and even cosmic interactions. Due to the complexity of the cloud system, present-day descriptions of clouds suffer from simplifications, inadequate parameterizations, and omissions. Sometimes the most fundamental physics hidden behind these simplifications and parameterizations is not known, and a wide scope of view can sometimes prevent a 'microscopic', deep insight into the detail. Only the expertise offered by scientists focused on particular elementary processes involved in this complicated pattern of interactions allows us to shape elements of the puzzle from which a general picture of clouds can be created. To be useful, every element of the puzzle must be shaped precisely. This often creates problems in communication between the sciences responsible for shaping

  19. Knowledge focus via software agents

    NASA Astrophysics Data System (ADS)

    Henager, Donald E.

    2001-09-01

    The essence of military Command and Control (C2) is making knowledge intensive decisions in a limited amount of time using uncertain, incorrect, or outdated information. It is essential to provide tools to decision-makers that provide: * Management of friendly forces by treating the "friendly resources as a system". * Rapid assessment of effects of military actions againt the "enemy as a system". * Assessment of how an enemy should, can, and could react to friendly military activities. Software agents in the form of mission agents, target agents, maintenance agents, and logistics agents can meet this information challenge. The role of each agent is to know all the details about its assigned mission, target, maintenance, or logistics entity. The Mission Agent would fight for mission resources based on the mission priority and analyze the effect that a proposed mission's results would have on the enemy. The Target Agent (TA) communicates with other targets to determine its role in the system of targets. A system of TAs would be able to inform a planner or analyst of the status of a system of targets, the effect of that status, adn the effect of attacks on that system. The system of TAs would also be able to analyze possible enemy reactions to attack by determining ways to minimize the effect of attack, such as rerouting traffic or using deception. The Maintenance Agent would scheudle maintenance events and notify the maintenance unit. The Logistics Agent would manage shipment and delivery of supplies to maintain appropriate levels of weapons, fuel and spare parts. The central idea underlying this case of software agents is knowledge focus. Software agents are createad automatically to focus their attention on individual real-world entities (e.g., missions, targets) and view the world from that entities perspective. The agent autonomously monitors the entity, identifies problems/opportunities, formulates solutions, and informs the decision-maker. The agent must be

  20. Findings: LANL outsourcing focus groups

    SciTech Connect

    Jannotta, M.J.; McCabe, V.B.

    1996-12-31

    In March 1996, a series of 24 3-hour dialog focus groups were held with randomly selected Laboratory employees and contractors to gain their perceptions regarding potentials and problems for privatization and consolidation. A secondary goal was to educate and inform the workforce about potentials and issues in privatization and consolidation. Two hundred and thirty-six participants engaged in a learning session and structured input exercises resulting in 2,768 usable comments. Comments were categorized using standard qualitative methods; resulting categories included positive and negative comments on four models (consolidation, spin offs, outsourcing, and corporate partnering) and implications for the workforce, the Laboratory, and the local economy. Categories were in the areas of increasing/decreasing jobs, expertise, opportunity/salary/benefits, quality/efficiency, and effect on the local area and economy. An additional concern was losing Laboratory culture and history. Data were gathered and categorized on employee opinion regarding elements of successful transition to the four models, and issues emerged in the areas of terms and conditions of employment; communication; involvement; sound business planning; ethics and fairness; community infrastructure. From the aggregated opinion of the participants, it is recommended that decision-makers: Plan using sound business principles and continually communicate plans to the workforce; Respect workforce investments in the Laboratory; Tell the workforce exactly what is going on at all times; Understand that economic growth in Northern New Mexico is not universally viewed as positive; and Establish dialog with stakeholders on growth issues.

  1. Patient satisfaction: focusing on "excellent".

    PubMed

    Otani, Koichiro; Waterman, Brian; Faulkner, Kelly M; Boslaugh, Sarah; Burroughs, Thomas E; Dunagan, W Claiborne

    2009-01-01

    In an emerging competitive market such as healthcare, managers should focus on achieving excellent ratings to distinguish their organization from others. When it comes to customer loyalty, "excellent" has a different meaning. Customers who are merely satisfied often do not come back. The purpose of this study was to find out what influences adult patients to rate their overall experience as "excellent." The study used patient satisfaction data collected from one major academic hospital and four community hospitals. After conducting a multiple logistic regression analysis, certain attributes were shown to be more likely than others to influence patients to rate their experiences as excellent. The study revealed that staff care is the most influential attribute, followed by nursing care. These two attributes are distinctively stronger drivers of overall satisfaction than are the other attributes studied (i.e., physician care, admission process, room, and food). Staff care and nursing care are under the control of healthcare managers. If improvements are needed, they can be accomplished through training programs such as total quality management or continuous quality improvement, through which staff employees and nurses learn to be sensitive to patients' needs. Satisfying patients' needs is the first step toward having loyal patients, so hospitals that strive to ensure their patients are completely satisfied are more likely to prosper. PMID:19413164

  2. Focus issue introduction: nonlinear photonics.

    PubMed

    Akhmediev, Nail; Rottwitt, Karsten

    2012-11-19

    It is now 23 years since the first Topical Meeting "Nonlinear Guided Wave Phenomena" (Houston, TX, February 2-4, 1989) has been organised by George Stegeman and Allan Boardman with support of the Optical Society of America. These series of the OSA conferences known as NLGW, continued under the name "Nonlinear Photonics" starting from 2007. The latest one, in Colorado Springs in June 17-21, 2012 has been a great success despite the fierce fires advancing around the city at the time of the conference. This Focus issue is a collection of several papers presented at the conference with extended content submitted to Optics Express. Although this collection is small in comparison to the total number of papers presented at the conference, it gives a flavor of the topics considered at the meeting. It is also worthy to mention here that the next meeting "Nonlinear Photonics" is planned to be held in Barcelona - one of the main European centers on this subject.

  3. EDITORIAL: Focus on Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    2003-09-01

    The study of carbon nanotubes, since their discovery by Iijima in 1991, has become a full research field with significant contributions from all areas of research in solid-state and molecular physics and also from chemistry. This Focus Issue in New Journal of Physics reflects this active research, and presents articles detailing significant advances in the production of carbon nanotubes, the study of their mechanical and vibrational properties, electronic properties and optical transitions, and electrical and transport properties. Fundamental research, both theoretical and experimental, represents part of this progress. The potential applications of nanotubes will rely on the progress made in understanding their fundamental physics and chemistry, as presented here. We believe this Focus Issue will be an excellent guide for both beginners and experts in the research field of carbon nanotubes. It has been a great pleasure to edit the many excellent contributions from Europe, Japan, and the US, as well from a number of other countries, and to witness the remarkable effort put into the manuscripts by the contributors. We thank all the authors and referees involved in the process. In particular, we would like to express our gratitude to Alexander Bradshaw, who invited us put together this Focus Issue, and to Tim Smith and the New Journal of Physics staff for their extremely efficient handling of the manuscripts. Focus on Carbon Nanotubes Contents <;A article="1367-2630/5/1/117">Transport theory of carbon nanotube Y junctions R Egger, B Trauzettel, S Chen and F Siano The tubular conical helix of graphitic boron nitride F F Xu, Y Bando and D Golberg Formation pathways for single-wall carbon nanotube multiterminal junctions Inna Ponomareva, Leonid A Chernozatonskii, Antonis N Andriotis and Madhu Menon Synthesis and manipulation of carbon nanotubes J W Seo, E Couteau

  4. EDITORIAL: Focus on Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    2003-09-01

    The study of carbon nanotubes, since their discovery by Iijima in 1991, has become a full research field with significant contributions from all areas of research in solid-state and molecular physics and also from chemistry. This Focus Issue in New Journal of Physics reflects this active research, and presents articles detailing significant advances in the production of carbon nanotubes, the study of their mechanical and vibrational properties, electronic properties and optical transitions, and electrical and transport properties. Fundamental research, both theoretical and experimental, represents part of this progress. The potential applications of nanotubes will rely on the progress made in understanding their fundamental physics and chemistry, as presented here. We believe this Focus Issue will be an excellent guide for both beginners and experts in the research field of carbon nanotubes. It has been a great pleasure to edit the many excellent contributions from Europe, Japan, and the US, as well from a number of other countries, and to witness the remarkable effort put into the manuscripts by the contributors. We thank all the authors and referees involved in the process. In particular, we would like to express our gratitude to Alexander Bradshaw, who invited us put together this Focus Issue, and to Tim Smith and the New Journal of Physics staff for their extremely efficient handling of the manuscripts. Focus on Carbon Nanotubes Contents Transport theory of carbon nanotube Y junctions R Egger, B Trauzettel, S Chen and F Siano The tubular conical helix of graphitic boron nitride F F Xu, Y Bando and D Golberg Formation pathways for single-wall carbon nanotube multiterminal junctions Inna Ponomareva, Leonid A Chernozatonskii, Antonis N Andriotis and Madhu Menon Synthesis and manipulation of carbon nanotubes J W Seo, E Couteau, P Umek, K Hernadi, P Marcoux, B Lukic, Cs Mikó, M Milas, R Gaál and L Forró Transitional behaviour in the transformation from active end

  5. SIAM Workshop: Focus on Diversity

    SciTech Connect

    2000-07-12

    The Fourth SlAM Graduate Student Focus on Diversity workshop was held on July 12, 2000 at the Westin Rio Mar Hotel in Rio Grande, Puerto Rico. The Department of Energy provided partial support for this event. The day-long workshop consisted of several different activities. The meeting opened with a discussion of some data collected by the American Mathematical Society on Ph.D.'s awarded in the U.S. to citizens and non-citizens, further classified as blacks, latinos, asians and native americans. The activity continued with nine technical talks by underrepresented minority graduate students, informal luncheon and pizza breaks to foster social interaction, and an evening forum chaired by Dr. Richard Tapia (Rice University) in which issues related to the participation of minorities in national meetings and proposal writing where discussed. These sessions were open to the entire SIAM community and served to highlight the progress, achievements, and aspirations of the workshop participants. The students attended as well the three SlAM plenary talks during the day and the community lecture in the evening. The activity had a lively participation of students and representatives from various academic institutions and sponsoring agencies. In particular, we had the participation of 24 undergraduate students from the Mathematics REU program of the University of Puerto Rico at Humacao.

  6. Aerosol beam-focus laser-induced plasma spectrometer device

    DOEpatents

    Cheng, Meng-Dawn

    2002-01-01

    An apparatus for detecting elements in an aerosol includes an aerosol beam focuser for concentrating aerosol into an aerosol beam; a laser for directing a laser beam into the aerosol beam to form a plasma; a detection device that detects a wavelength of a light emission caused by the formation of the plasma. The detection device can be a spectrometer having at least one grating and a gated intensified charge-coupled device. The apparatus may also include a processor that correlates the wavelength of the light emission caused by the formation of the plasma with an identity of an element that corresponds to the wavelength. Furthermore, the apparatus can also include an aerosol generator for forming an aerosol beam from bulk materials. A method for detecting elements in an aerosol is also disclosed.

  7. In vivo acoustic and photoacoustic focusing of circulating cells

    NASA Astrophysics Data System (ADS)

    Galanzha, Ekaterina I.; Viegas, Mark G.; Malinsky, Taras I.; Melerzanov, Alexander V.; Juratli, Mazen A.; Sarimollaoglu, Mustafa; Nedosekin, Dmitry A.; Zharov, Vladimir P.

    2016-03-01

    In vivo flow cytometry using vessels as natural tubes with native cell flows has revolutionized the study of rare circulating tumor cells in a complex blood background. However, the presence of many blood cells in the detection volume makes it difficult to count each cell in this volume. We introduce method for manipulation of circulating cells in vivo with the use of gradient acoustic forces induced by ultrasound and photoacoustic waves. In a murine model, we demonstrated cell trapping, redirecting and focusing in blood and lymph flow into a tight stream, noninvasive wall-free transportation of blood, and the potential for photoacoustic detection of sickle cells without labeling and of leukocytes targeted by functionalized nanoparticles. Integration of cell focusing with intravital imaging methods may provide a versatile biological tool for single-cell analysis in circulation, with a focus on in vivo needleless blood tests, and preclinical studies of human diseases in animal models.

  8. In vivo acoustic and photoacoustic focusing of circulating cells

    PubMed Central

    Galanzha, Ekaterina I.; Viegas, Mark G.; Malinsky, Taras I.; Melerzanov, Alexander V.; Juratli, Mazen A.; Sarimollaoglu, Mustafa; Nedosekin, Dmitry A.; Zharov, Vladimir P.

    2016-01-01

    In vivo flow cytometry using vessels as natural tubes with native cell flows has revolutionized the study of rare circulating tumor cells in a complex blood background. However, the presence of many blood cells in the detection volume makes it difficult to count each cell in this volume. We introduce method for manipulation of circulating cells in vivo with the use of gradient acoustic forces induced by ultrasound and photoacoustic waves. In a murine model, we demonstrated cell trapping, redirecting and focusing in blood and lymph flow into a tight stream, noninvasive wall-free transportation of blood, and the potential for photoacoustic detection of sickle cells without labeling and of leukocytes targeted by functionalized nanoparticles. Integration of cell focusing with intravital imaging methods may provide a versatile biological tool for single-cell analysis in circulation, with a focus on in vivo needleless blood tests, and preclinical studies of human diseases in animal models. PMID:26979811

  9. MAMA Spectroscopic Sensitivity and Focus Monitor Cycle 18

    NASA Astrophysics Data System (ADS)

    Osten, Rachel

    2010-09-01

    Monitor sensitivity of each MAMA grating mode to detect any change due tocontamination or other causes. Also monitor the STIS focus in a spectroscopic and animaging mode.Obtain exposures in each of the 2 low-resolution MAMA spectroscopic modes every 4 months, in each of the 2 medium-resolution modes once a year, and in each of the 4 echelle modes every 3 months,using unique calibration standards for each mode, and ratio the results to the firstobservations to detect any trends. In addition, each L-mode sequence will be preceded by twospectroscopic ACQ/PEAKs with the CCD/G230LB and crossed linear patterns, with the purpose of measuringthe focus {PSF across the dispersion as a function of UV wavelength}; and each M-mode sequence will be preceded by aCCD/F28X50OII direct image also to monitor the focus.Whenever possible, obtain parallel airglow spectra with COS.

  10. MAMA Spectroscopic Sensitivity and Focus Monitor Cycle 20

    NASA Astrophysics Data System (ADS)

    Holland, Stephen

    2012-10-01

    Monitor sensitivity of each MAMA grating mode to detect any change due tocontamination or other causes. Also monitor the STIS focus in a spectroscopic and animaging mode.Obtain exposures in each of the 2 low-resolution MAMA spectroscopic modes every 4 months, in each of the 2 medium-resolution modes once a year, and in each of the 4 echelle modes every 3 months,using unique calibration standards for each mode, and ratio the results to the firstobservations to detect any trends. In addition, each L-mode sequence will be preceded by twospectroscopic ACQ/PEAKs with the CCD/G230LB and crossed linear patterns, with the purpose of measuringthe focus {PSF across the dispersion as a function of UV wavelength}; and each M-mode sequence will be preceded by aCCD/F28X50OII direct image also to monitor the focus.Whenever possible, obtain parallel airglow spectra with COS.

  11. MAMA Spectroscopic Sensitivity and Focus Monitor Cycle 21

    NASA Astrophysics Data System (ADS)

    Sana, Hugues

    2013-10-01

    Monitor sensitivity of each MAMA grating mode to detect any change due tocontamination or other causes. Also monitor the STIS focus in a spectroscopic and animaging mode.Obtain exposures in each of the 2 low-resolution MAMA spectroscopic modes every 4 months, in each of the 2 medium-resolution modes once a year, and in each of the 4 echelle modes every 3 months,using unique calibration standards for each mode, and ratio the results to the firstobservations to detect any trends. In addition, each L-mode sequence will be preceded by twospectroscopic ACQ/PEAKs with the CCD/G230LB and crossed linear patterns, with the purpose of measuringthe focus {PSF across the dispersion as a function of UV wavelength}; and each M-mode sequence will be preceded by aCCD/F28X50OII direct image also to monitor the focus.Whenever possible, obtain parallel airglow spectra with COS.

  12. MAMA Spectroscopic Sensitivity and Focus Monitor Cycle 19

    NASA Astrophysics Data System (ADS)

    Bostroem, Azalee

    2011-10-01

    Monitor sensitivity of each MAMA grating mode to detect any change due tocontamination or other causes. Also monitor the STIS focus in a spectroscopic and animaging mode.Obtain exposures in each of the 2 low-resolution MAMA spectroscopic modes every 4 months, in each of the 2 medium-resolution modes once a year, and in each of the 4 echelle modes every 3 months,using unique calibration standards for each mode, and ratio the results to the firstobservations to detect any trends. In addition, each L-mode sequence will be preceded by twospectroscopic ACQ/PEAKs with the CCD/G230LB and crossed linear patterns, with the purpose of measuringthe focus {PSF across the dispersion as a function of UV wavelength}; and each M-mode sequence will be preceded by aCCD/F28X50OII direct image also to monitor the focus.Whenever possible, obtain parallel airglow spectra with COS.

  13. Molecular collisions coming into focus.

    PubMed

    Onvlee, Jolijn; Vogels, Sjoerd N; von Zastrow, Alexander; Parker, David H; van de Meerakker, Sebastiaan Y T

    2014-08-14

    The Stark deceleration method exploits the concepts of charged particle accelerator physics to produce beams of neutral polar molecules with an almost perfect quantum state purity, a tunable velocity and a narrow velocity distribution. These monochromatic molecular beams offer interesting perspectives for precise studies of molecular scattering processes, in particular when used in conjunction with state-of-the-art laser-based detection techniques such as velocity map imaging. Here, we describe crossed beam scattering experiments in which the Stark deceleration method is combined with the velocity map imaging technique. The narrow velocity spread of Stark-decelerated molecular beams results in scattering images with unprecedented velocity and angular resolution. We demonstrate this by resolving quantum diffraction oscillations in state-to-state inelastic differential scattering cross sections for collisions between NO radicals and rare gas atoms. We describe the future prospects of this "best-of-two-worlds" combination, ranging from scattering studies at low collision energies to bimolecular scattering using two decelerators, and discuss the challenges that lie ahead to achieve these goals. PMID:24967721

  14. Topography of somatosensory processing: cerebral lateralization and focused attention.

    PubMed

    Meador, K J; Allison, J D; Loring, D W; Lavin, T B; Pillai, J J

    2002-03-01

    Healthy dextrals underwent fMRI during a task of graphesthesia requiring detection of any number written consecutively from an otherwise random number sequence. Test conditions included (1) focus on unilateral right hand stimuli, (2) focus on unilateral left hand stimuli, (3) focus on right hand only during bilateral hand stimulation, (4) focus on left hand only during bilateral hand stimulation, and (5) rest. Attention to unilateral hand stimulation produced bihemispheric activation with minimal or no activation of ipsilateral primary sensorimotor region. Attention to unilateral left hand stimuli resulted in more activation than attention to unilateral right hand stimuli. Stimulation of the nonattended hand activated the contralateral somatosensory area, but to a lesser spatial extent than attended stimuli. Comparing focused attention to the left versus right side during identical sensory inputs (i.e., bilateral hand stimulation), focused attention to the right hand increased activation in the left somatosensory region, but focused attention to the left hand increased activation in both cerebral hemispheres. Thus, focused attention to unilateral somatosensory stimuli produces bilateral cerebral activation, but the increase in blood flow is greater in the contralateral hemisphere. Unattended stimuli activate the contralateral primary somatosensory area. Left/right asymmetries were demonstrated consistent with cerebral lateralization.

  15. SAR change detection MTI

    NASA Astrophysics Data System (ADS)

    Scarborough, Steven; Lemanski, Christopher; Nichols, Howard; Owirka, Gregory; Minardi, Michael; Hale, Todd

    2006-05-01

    This paper examines the theory, application, and results of using single-channel synthetic aperture radar (SAR) data with Moving Reference Processing (MRP) to focus and geolocate moving targets. Moving targets within a standard SAR imaging scene are defocused, displaced, or completely missing in the final image. Building on previous research at AFRL, the SAR-MRP method focuses and geolocates moving targets by reprocessing the SAR data to focus the movers rather than the stationary clutter. SAR change detection is used so that target detection and focusing is performed more robustly. In the cases where moving target returns possess the same range versus slow-time histories, a geolocation ambiguity results. This ambiguity can be resolved in a number of ways. This paper concludes by applying the SAR-MRP method to high-frequency radar measurements from persistent continuous-dwell SAR observations of a moving target.

  16. On-chip pumping for pressure mobilization of the focused zones following microchip isoelectric focusing.

    PubMed

    Guillo, Christelle; Karlinsey, James M; Landers, James P

    2007-01-01

    Isoelectric focusing (IEF), traditionally accomplished in slab or tube gels, has also been performed extensively in capillary and, more recently, in microchip formats. IEF separations performed in microchips typically use electroosmotic flow (EOF) or chemical treatment to mobilize the focused zones past the detection point. This report describes the development and optimization of a microchip IEF method in a hybrid PDMS-glass device capable of controlling the mobilization of the focused zones past the detector using on-chip diaphragm pumping. The microchip design consisted of a glass fluid layer (separation channels), a PDMS layer and a glass valve layer (pressure connections and valve seats). Pressure mobilization was achieved on-chip using a diaphragm pump consisting of a series of reversible elastomeric valves, where a central diaphragm valve determined the volume of solution displaced while the gate valves on either side imparted directionality. The pumping rate could be adjusted to control the mobilization flow rate by varying the actuation times and pressure applied to the PDMS to actuate the valves. In order to compare the separation obtained using the chip with that obtained in a capillary, a serpentine channel design was used to match the separation length of the capillary, thereby evaluating the effect of diaphragm pumping itself on the overall separation quality. The optimized mIEF method was applied to the separation of labeled amino acids. PMID:17180213

  17. EDITORIAL: Focus on Molecular Electronics FOCUS ON MOLECULAR ELECTRONICS

    NASA Astrophysics Data System (ADS)

    Scheer, Elke; Reineker, Peter

    2008-06-01

    The notion 'molecular electronics' has been used more frequently since the 1970s and summarizes a series of physical phenomena and ideas for their application in connection with organic molecules, oligomers, polymers, organic aggregates and solids. The properties studied in this field were connected to optical and electrical phenomena, such as optical absorption, fluorescence, nonlinear optics, energy transport, charge transfer, electrical conductance, and electron and nuclear spin-resonance. The final goal was and is to build devices which can compete or surpass some aspects of inorganic semiconductor devices. For example, on the basis of organic molecules there exist rectifiers, transistors, molecular wires, organic light emitting diodes, elements for photovoltaics, and displays. With respect to applications, one aspect of the organic materials is their broad variability and the lower effort and costs for their processability. The step from microstructures to the investigation of nanostructures is a big challenge also in this field and has lead to what nowadays is called molecular electronics in its narrow sense. In this field the subjects of the studies are often single molecules, e.g. single molecule optical spectroscopy, electrical conductance, i.e. charge transport through a single molecule, the influence of vibrational degrees of freedom, etc. A challenge here is to provide the techniques for addressing in a reproducible way the molecular scale. In another approach small molecular ensembles are studied in order to avoid artefacts from particular contact situations. The recent development of the field is presented in [1-8]. In this Focus Issue we present new results in the field of 'molecular electronics', both in its broad and specialized sense. One of the basic questions is the distribution of the energy levels responsible for optical absorption on the one hand and for the transport of charge on the other. A still unanswered question is whether the Wannier

  18. Recent advances in microfluidic detection systems

    PubMed Central

    Baker, Christopher A; Duong, Cindy T; Grimley, Alix; Roper, Michael G

    2009-01-01

    There are numerous detection methods available for methods are being put to use for detection on these miniaturized systems, with the analyte of interest driving the choice of detection method. In this article, we summarize microfluidic 2 years. More focus is given to unconventional approaches to detection routes and novel strategies for performing high-sensitivity detection. PMID:20414455

  19. EDITORIAL: Focus on Molecular Electronics FOCUS ON MOLECULAR ELECTRONICS

    NASA Astrophysics Data System (ADS)

    Scheer, Elke; Reineker, Peter

    2008-06-01

    The notion 'molecular electronics' has been used more frequently since the 1970s and summarizes a series of physical phenomena and ideas for their application in connection with organic molecules, oligomers, polymers, organic aggregates and solids. The properties studied in this field were connected to optical and electrical phenomena, such as optical absorption, fluorescence, nonlinear optics, energy transport, charge transfer, electrical conductance, and electron and nuclear spin-resonance. The final goal was and is to build devices which can compete or surpass some aspects of inorganic semiconductor devices. For example, on the basis of organic molecules there exist rectifiers, transistors, molecular wires, organic light emitting diodes, elements for photovoltaics, and displays. With respect to applications, one aspect of the organic materials is their broad variability and the lower effort and costs for their processability. The step from microstructures to the investigation of nanostructures is a big challenge also in this field and has lead to what nowadays is called molecular electronics in its narrow sense. In this field the subjects of the studies are often single molecules, e.g. single molecule optical spectroscopy, electrical conductance, i.e. charge transport through a single molecule, the influence of vibrational degrees of freedom, etc. A challenge here is to provide the techniques for addressing in a reproducible way the molecular scale. In another approach small molecular ensembles are studied in order to avoid artefacts from particular contact situations. The recent development of the field is presented in [1-8]. In this Focus Issue we present new results in the field of 'molecular electronics', both in its broad and specialized sense. One of the basic questions is the distribution of the energy levels responsible for optical absorption on the one hand and for the transport of charge on the other. A still unanswered question is whether the Wannier

  20. Focus groups reveal consumer ambivalence.

    PubMed

    1983-01-01

    According to qualitative research, Salvadoreans are ambivalent about the use of contraceptives. Since complete responsibility for management of the CSM project was accepted by the Association Demografica Salvadorena (ADS), the agency which operates the contraceptive social marketing project in El Salvador, in November 1980, the need for decisions in such areas as product price increases, introduction of new condom brands, promotion of the vaginal foaming tablet, and assessment of product sales performance had arisen. The ICSMP funded market research, completed during 1983, was intended to provide the data on which such decisions by ADS could be based. The qualitative research involved 8 focus groups, comprised of men and women, aged 18-45, contraceptive users and nonusers, from the middle and lower socioeconomic strata of the city of San Salvador and other suburban areas. In each group a moderator led discussion of family planning and probed respondents for specific attitudes, knowledge, and behavior regarding the use of contraceptives. To assess attitudes at a more emotional level, moderators asked respondents to "draw" their ideas on certain issues. A marked discrepancy was revealed between respondents' intellectual responses to the issues raised in group discussion, as opposed to their feelings expressed in the drawings. Intellectually, participants responded very positively to family planning practice, but when they were asked to draw their perceptions, ambivalent feelings emerged. Drawings of both the user and the nonuser convey primarily negative aspects for either choice. The user is tense and moody toward her children; the nonuser loses her attractiveness and "dies." Figures also show drawings of some of the attitudes of single and married male participants. 1 drawing shows an incomplete and a complete circle, symbolizing a sterilized man (incomplete) and a nonsterilized man (complete). Another picture depicts a chained man who has lost his freedom

  1. The Unfocused Focus Group: Benefit or Bane?

    ERIC Educational Resources Information Center

    Franz, Nancy K.

    2011-01-01

    Facilitating successful focus groups requires both science and art. One element that can fully challenge focus group facilitators includes how to handle the unfocused focus group. This article describes "unfocus" and the benefits and disadvantages of unfocus in focus groups. Lessons learned from and approaches taken on this journey are shared to…

  2. EDITORIAL: Focus on Plasma Medicine

    NASA Astrophysics Data System (ADS)

    Morfill, G. E.; Kong, M. G.; Zimmermann, J. L.

    2009-11-01

    'Plasma Healthcare' is an emerging interdisciplinary research topic of rapidly growing importance, exploring considerable opportunities at the interface of plasma physics, chemistry and engineering with life sciences. Some of the scientific discoveries reported so far have already demonstrated clear benefits for healthcare in areas of medicine, food safety, environmental hygiene, and cosmetics. Examples include ongoing studies of prion inactivation, chronic wound treatment and plasma-mediated cancer therapy. Current research ranges from basic physical processes, plasma chemical design, to the interaction of plasmas with (i) eukaryotic (mammalian) cells; (ii) prokaryotic (bacteria) cells, viruses, spores and fungi; (iii) DNA, lipids, proteins and cell membranes; and (iv) living human, animal and plant tissues in the presence of biofluids. Of diverse interests in this new field is the need for hospital disinfection, in particular with respect to the alarming increase in bacterial resistance to antibiotics, the concomitant needs in private practices, nursing homes etc, the applications in personal hygiene—and the enticing possibility to 'design' plasmas as possible pharmaceutical products, employing ionic as well as molecular agents for medical treatment. The 'delivery' of the reactive plasma agents occurs at the gaseous level, which means that there is no need for a carrier medium and access to the treatment surface is optimal. This focus issue provides a close look at the current state of the art in Plasma Medicine with a number of forefront research articles as well as an introductory review. Focus on Plasma Medicine Contents Application of epifluorescence scanning for monitoring the efficacy of protein removal by RF gas-plasma decontamination Helen C Baxter, Patricia R Richardson, Gaynor A Campbell, Valeri I Kovalev, Robert Maier, James S Barton, Anita C Jones, Greg DeLarge, Mark Casey and Robert L Baxter Inactivation factors of spore-forming bacteria using low

  3. EDITORIAL: Focus on Plasma Medicine

    NASA Astrophysics Data System (ADS)

    Morfill, G. E.; Kong, M. G.; Zimmermann, J. L.

    2009-11-01

    'Plasma Healthcare' is an emerging interdisciplinary research topic of rapidly growing importance, exploring considerable opportunities at the interface of plasma physics, chemistry and engineering with life sciences. Some of the scientific discoveries reported so far have already demonstrated clear benefits for healthcare in areas of medicine, food safety, environmental hygiene, and cosmetics. Examples include ongoing studies of prion inactivation, chronic wound treatment and plasma-mediated cancer therapy. Current research ranges from basic physical processes, plasma chemical design, to the interaction of plasmas with (i) eukaryotic (mammalian) cells; (ii) prokaryotic (bacteria) cells, viruses, spores and fungi; (iii) DNA, lipids, proteins and cell membranes; and (iv) living human, animal and plant tissues in the presence of biofluids. Of diverse interests in this new field is the need for hospital disinfection, in particular with respect to the alarming increase in bacterial resistance to antibiotics, the concomitant needs in private practices, nursing homes etc, the applications in personal hygiene—and the enticing possibility to 'design' plasmas as possible pharmaceutical products, employing ionic as well as molecular agents for medical treatment. The 'delivery' of the reactive plasma agents occurs at the gaseous level, which means that there is no need for a carrier medium and access to the treatment surface is optimal. This focus issue provides a close look at the current state of the art in Plasma Medicine with a number of forefront research articles as well as an introductory review. Focus on Plasma Medicine Contents Application of epifluorescence scanning for monitoring the efficacy of protein removal by RF gas-plasma decontamination Helen C Baxter, Patricia R Richardson, Gaynor A Campbell, Valeri I Kovalev, Robert Maier, James S Barton, Anita C Jones, Greg DeLarge, Mark Casey and Robert L Baxter Inactivation factors of spore-forming bacteria using low

  4. Hydrodynamic focusing of conducting fluids for conductivity-based biosensors.

    PubMed

    Nasir, Mansoor; Ateya, Daniel A; Burk, Diana; Golden, Joel P; Ligler, Frances S

    2010-02-15

    Hydrodynamic focusing of a conducting fluid by a non-conducting fluid to form a constricted current path between two sensing electrodes is implemented in order to enhance the sensitivity of a 4-electrode conductance-based biosensor. The sensor has a simple two-inlet T-junction design and performs four-point conductivity measurements to detect particles immobilized between the sensing electrode pair. Computational simulations conducted in conjunction with experimental flow studies using confocal microscopy show that a flat profile for the focused layer is dependent on the Reynolds number for the chosen flow parameters. The results also indicate that a flat focused layer is desirable for both increased sensitivity as well as surface-binding efficiency. Proof of concept for conductance measurements in a hydrodynamically focused conducting fluid was demonstrated with entrapped magnetic beads. PMID:19932019

  5. EDITORIAL: Focus on Attosecond Physics

    NASA Astrophysics Data System (ADS)

    Bandrauk, André D.; Krausz, Ferenc; Starace, Anthony F.

    2008-02-01

    future involve using overdense plasmas. Electronic processes on sub-atomic spatio-temporal scales are the basis of chemical physics, atomic, molecular, and optical physics, materials science, and even some life science processes. Research in these areas using the new attosecond tools will advance together with the ability to control electrons themselves. Indeed, we expect that developments will advance in a way that is similar to advances that have occurred on the femtosecond time scale, in which much previous experimental and theoretical work on the interaction of coherent light sources has led to the development of means for 'coherent control' of nuclear motion in molecules. This focus issue of New Journal of Physics is centered on experimental and theoretical advances in the development of new methodologies and tools for electron control on the attosecond time scale. Topics such as the efficient generation of harmonics; the generation of attosecond pulses, including those having only a few cycles and those produced from overdense plasmas; the description of various nonlinear, nonperturbative laser-matter interactions, including many-electron effects and few-cycle pulse effects; the analysis of ultrashort propagation effects in atomic and molecular media; and the development of inversion methods for electron tomography, as well as many other topics, are addressed in the current focus issue dedicated to the new field of 'Attosecond Physics'. Focus on Attosecond Physics Contents Observing the attosecond dynamics of nuclear wavepackets in molecules by using high harmonic generation in mixed gases Tsuneto Kanai, Eiji J Takahashi, Yasuo Nabekawa and Katsumi Midorikawa Core-polarization effects in molecular high harmonic generation G Jordan and A Scrinzi Interferometric autocorrelation of an attosecond pulse train calculated using feasible formulae Y Nabekawa and K Midorikawa Attosecond pulse generation from aligned molecules—dynamics and propagation in H2+ E Lorin, S

  6. Focused electron beam induced deposition: A perspective

    PubMed Central

    Porrati, Fabrizio; Schwalb, Christian; Winhold, Marcel; Sachser, Roland; Dukic, Maja; Adams, Jonathan; Fantner, Georg

    2012-01-01

    -sensing and the detection of small, inhomogeneous magnetic fields by employing nanogranular FEBID structures are highlighted. Conclusion: FEBID has now reached a state of maturity that allows a shift of the focus towards the development of new application fields, be it in basic research or applied. This is shown for selected examples in the present review. At the same time, when seen from a broader perspective, FEBID still has to live up to the original idea of providing a tool for electron-controlled chemistry on the nanometer scale. This has to be understood in the sense that, by providing a suitable environment during the FEBID process, the outcome of the electron-induced reactions can be steered in a controlled way towards yielding the desired composition of the products. The development of a FEBID-specialized surface chemistry is mostly still in its infancy. Next to application development, it is this aspect that will likely be a guiding light for the future development of the field of focused electron beam induced deposition. PMID:23019557

  7. 3D flow focusing for microfluidic flow cytometry with ultrasonics

    NASA Astrophysics Data System (ADS)

    Gnyawali, Vaskar; Strohm, Eric M.; Daghighi, Yasaman; van de Vondervoort, Mia; Kolios, Michael C.; Tsai, Scott S. H.

    2015-11-01

    We are developing a flow cytometer that detects unique acoustic signature waves generated from single cells due to interactions between the cells and ultrasound waves. The generated acoustic waves depend on the size and biomechanical properties of the cells and are sufficient for identifying cells in the medium. A microfluidic system capable of focusing cells through a 10 x 10 μm ultrasound beam cross section was developed to facilitate acoustic measurements of single cells. The cells are streamlined in a hydro-dynamically 3D focused flow in a 300 x 300 μm channel made using PDMS. 3D focusing is realized by lateral sheath flows and an inlet needle (inner diameter 100 μm). The accuracy of the 3D flow focusing is measured using a dye and detecting its localization using confocal microscopy. Each flowing cell would be probed by an ultrasound pulse, which has a center frequency of 375 MHz and bandwidth of 250 MHz. The same probe would also be used for recording the scattered waves from the cells, which would be processed to distinguish the physical and biomechanical characteristics of the cells, eventually identifying them. This technique has potential applications in detecting circulating tumor cells, blood cells and blood-related diseases.

  8. Sensors for process control Focus Team report

    SciTech Connect

    Not Available

    1993-09-01

    At the Semiconductor Technology Workshop, held in November 1992, the Semiconductor Industry Association (SIA) convened 179 semiconductor technology experts to assess the 15-year outlook for the semiconductor manufacturing industry. The output of the Workshop, a document entitled ``Semiconductor Technology: Workshop Working Group Reports,`` contained an overall roadmap for the technology characteristics envisioned in integrated circuits (ICs) for the period 1992--2007. In addition, the document contained individual roadmaps for numerous key areas in IC manufacturing, such as film deposition, thermal processing, manufacturing systems, exposure technology, etc. The SIA Report did not contain a separate roadmap for contamination free manufacturing (CFM). A key component of CFM for the next 15 years is the use of sensors for (1) defect reduction, (2) improved product quality, (3) improved yield, (4) improved tool utilization through contamination reduction, and (5) real time process control in semiconductor fabrication. The objective of this Focus Team is to generate a Sensors for Process Control Roadmap. Implicit in this objective is the identification of gaps in current sensor technology so that research and development activity in the sensor industry can be stimulated to develop sensor systems capable of meeting the projected roadmap needs. Sensor performance features of interest include detection limit, specificity, sensitivity, ease of installation and maintenance, range, response time, accuracy, precision, ease and frequency of calibration, degree of automation, and adaptability to in-line process control applications.

  9. Focus takes time: structural effects on reading.

    PubMed

    Lowder, Matthew W; Gordon, Peter C

    2015-12-01

    Previous eye-tracking work has yielded inconsistent evidence regarding whether readers spend more or less time encoding focused information compared with information that is not focused. We report the results of an eye-tracking experiment that used syntactic structure to manipulate whether a target word was linguistically defocused, neutral, or focused, while controlling for possible oculomotor differences across conditions. As the structure of the sentence made the target word increasingly more focused, reading times systematically increased. We propose that the longer reading times for linguistically focused words reflect deeper encoding, which explains previous findings showing that readers have better subsequent memory for focused versus defocused information.

  10. Pre-impact fall detection.

    PubMed

    Hu, Xinyao; Qu, Xingda

    2016-06-01

    Pre-impact fall detection has been proposed to be an effective fall prevention strategy. In particular, it can help activate on-demand fall injury prevention systems (e.g. inflatable hip protectors) prior to fall impacts, and thus directly prevent the fall-related physical injuries. This paper gave a systematical review on pre-impact fall detection, and focused on the following aspects of the existing pre-impact fall detection research: fall detection apparatus, fall detection indicators, fall detection algorithms, and types of falls for fall detection evaluation. In addition, the performance of the existing pre-impact fall detection solutions were also reviewed and reported in terms of their sensitivity, specificity, and detection/lead time. This review also summarized the limitations in the existing pre-impact fall detection research, and proposed future research directions in this field.

  11. Pre-impact fall detection.

    PubMed

    Hu, Xinyao; Qu, Xingda

    2016-01-01

    Pre-impact fall detection has been proposed to be an effective fall prevention strategy. In particular, it can help activate on-demand fall injury prevention systems (e.g. inflatable hip protectors) prior to fall impacts, and thus directly prevent the fall-related physical injuries. This paper gave a systematical review on pre-impact fall detection, and focused on the following aspects of the existing pre-impact fall detection research: fall detection apparatus, fall detection indicators, fall detection algorithms, and types of falls for fall detection evaluation. In addition, the performance of the existing pre-impact fall detection solutions were also reviewed and reported in terms of their sensitivity, specificity, and detection/lead time. This review also summarized the limitations in the existing pre-impact fall detection research, and proposed future research directions in this field. PMID:27251528

  12. Focus on Communication: NIH Research to Results

    MedlinePlus

    ... Current Issue Past Issues Special Section: Focus on Communication NIH Research to Results Past Issues / Fall 2008 ... grew new hair cells. Read More "Focus on Communication" Articles Living with Hearing Loss / Anatomy of the ...

  13. Parent Leadership and Family Involvement (Special Focus).

    ERIC Educational Resources Information Center

    Wolf, Kathy Goetz, Ed.; Lalley, Jacqueline, Ed.

    1999-01-01

    This "Special Focus" issue of "America's Family Support Magazine," focuses on parent leadership and family involvement. Articles pertaining to this focus include: (1) "Forging Equal Partnerships" (Ahsan); (2) "Who Best Represents the Voice of Parents?" (Foster); (3) "Parent Leadership Training Programs" (Baum); (4) "Parents as Family Support…

  14. Techniques For Focusing In Zone Electrophoresis

    NASA Technical Reports Server (NTRS)

    Sharnez, Rizwan; Twitty, Garland E.; Sammons, David W.

    1994-01-01

    In two techniques for focusing in zone electrophoresis, force of applied electrical field in each charged particle balanced by restoring force of electro-osmosis. Two techniques: velocity-gradient focusing (VGF), suitable for rectangular electrophoresis chambers; and field-gradient focusing (FGF), suitable for step-shaped electrophoresis chambers.

  15. AXAF VETA-I mirror ring focus measurements

    NASA Technical Reports Server (NTRS)

    Tananbaum, H. D.; Zhao, P.

    1994-01-01

    The AXAF VETA-I mirror ring focus measurements were made with an HRI (microchannel plate) X-ray detector. The ring focus is a sharply focused ring formed by X-rays before they reach the VEAT-I focal plane. It is caused by spherical aberrations due to the finite source distance and the despace in the VETA-I test. The ring focus test reveals some aspects fo the test system distortions and the mirror surface figure which are difficult or impossible to detect at the focal plane. The test results show periodic modulations of the ring radius and width which could be caused by gravity, thermal, and/or epoxy shrinkage distortions. The strongest component of the modulation had a 12-fold symmetry, because these distortions were exerted on the mirror through 12 flexures of the VETA-I mount. Ring focus models were developed to simulate the ring image. The models were compared with the data to understand the test system distortions and the mirror glass imperfection. Further studies will be done to complete this work. The ring focus measurement is a very powerful test. We expect that a similar test for the finally assembled mirror of AXAD-I will be highly valuable.

  16. Auto-focusing method for remote gaze tracking camera

    NASA Astrophysics Data System (ADS)

    Lee, Won Oh; Lee, Hyeon Chang; Cho, Chul Woo; Gwon, Su Yeong; Park, Kang Ryoung; Lee, Heekyung; Cha, Jihun

    2012-06-01

    Gaze tracking determines what a user is looking at; the key challenge is to obtain well-focused eye images. This is not easy because the human eye is very small, whereas the required resolution of the image should be large enough for accurate detection of the pupil center. In addition, capturing a user's eye image by a remote gaze tracking system within a large working volume at a long Z distance requires a panning/tilting mechanism with a zoom lens, which makes it more difficult to acquire focused eye images. To solve this problem, a new auto-focusing method for remote gaze tracking is proposed. The proposed approach is novel in the following four ways: First, it is the first research on an auto-focusing method for a remote gaze tracking system. Second by using user-dependent calibration at initial stage, the weakness of the previous methods that use facial width in captured image to estimate Z distance between a user and camera, wherein each person has the individual variation of facial width, is solved. Third, the parameters of the modeled formula for estimating the Z distance are adaptively updated using the least squares regression method. Therefore, the focus becomes more accurate over time. Fourth, the relationship between the parameters and the face width is fitted locally according to the Z distance instead of by global fitting, which can enhance the accuracy of Z distance estimation. The results of an experiment with 10,000 images of 10 persons showed that the mean absolute error between the ground-truth Z distance measured by a Polhemus Patriot device and that estimated by the proposed method was 4.84 cm. A total of 95.61% of the images obtained by the proposed method were focused and could be used for gaze detection.

  17. [Pre-verbality in focusing and the need for self check. An attempt at "focusing check"].

    PubMed

    Masui, T; Ikemi, A; Murayama, S

    1983-06-01

    Though the Focusing process is not entirely non-verbal, in Focusing, careful attention is paid by the Focuser and the Listener to the pre-verbal experiential process. In other words, Focusing involves attending to the felt sense that is not easily expressed in words immediately. Hence, during the process of learning to Focus, the Focusing teacher attempts to communicate the experiences of Focusing to the student which are not easily done by words. Due to such difficulties, the Focusing student may (and quite frequently does) mistake the experiential process in Focusing with other processes. Often, the felt sense can be confused with other phenomena such as "autogenic discharge". Also the Focuser may not stay with the felt sense and drift into "free association" or frequently, certain processes in "meditation" can be confused with Focusing. Therefore, there is a need for a "check" by which the Focusing student can confirm the Focusing experience for himself. For the Focusing student, such a "check" serves not only to confirm the Focusing process, but also an aid to learning Focusing. We will report here a "Focusing Check" which we developed by translating Eugene Gendlin's "Focusing Check" and making several modifications in it so that it will be more understandable to the Japanese. Along with the "Focusing Check" we developed, the authors discuss the need for such a check.

  18. The hydrodynamic focusing effect inside rectangular microchannels

    NASA Astrophysics Data System (ADS)

    Lee, Gwo-Bin; Chang, Chih-Chang; Huang, Sung-Bin; Yang, Ruey-Jen

    2006-05-01

    This paper presents a theoretical and experimental investigation into the hydrodynamic focusing effect in rectangular microchannels. Two theoretical models for two-dimensional hydrodynamic focusing are proposed. The first model predicts the width of the focused stream in symmetric hydrodynamic focusing in microchannels of various aspect ratios. The second model predicts the location and the width of the focused stream in asymmetric hydrodynamic focusing in microchannels with a low or high aspect ratio. In both models, the theoretical results are shown to be in good agreement with the experimental data. Hence, the models provide a useful means of performing a theoretical analysis of flow control in microfluidic devices using hydrodynamic focusing effects. The ability of the proposed models to control the focused stream within a micro flow cytometer is verified in a series of experimental trials performed using polystyrene microparticles with a diameter of 20 µm. The experimental data show that the width of the focused stream can be reduced to the same order of magnitude as that of the particle size. Furthermore, it is shown that the microparticles can be successfully hydrodynamically focused and switched to the desired outlet port of the cytometer. Hence, the models presented in this study provide sufficient control to support cell/particle counting and sorting applications.

  19. The Development of Change Detection

    ERIC Educational Resources Information Center

    Shore, David I.; Burack, Jacob A.; Miller, Danny; Joseph, Shari; Enns, James T.

    2006-01-01

    Changes to a scene often go unnoticed if the objects of the change are unattended, making change detection an index of where attention is focused during scene perception. We measured change detection in school-age children and young adults by repeatedly alternating two versions of an image. To provide an age-fair assessment we used a bimanual…

  20. Sentence-Level Rewriting Detection

    ERIC Educational Resources Information Center

    Zhang, Fan; Litman, Diane

    2014-01-01

    Writers usually need iterations of revisions and edits during their writings. To better understand the process of rewriting, we need to know what has changed be-tween the revisions. Prior work mainly focuses on detecting corrections within sentences, which is at the level of words or phrases. This paper proposes to detect revision changes at the…

  1. Detective Scientist

    NASA Video Gallery

    NASA has many detectives looking for clues to solve a mystery, like "science detective" Monsi Roman. She is making sure the water and air on board the International Space Station are safe for the a...

  2. A universal symmetry detection algorithm.

    PubMed

    Maurer, Peter M

    2015-01-01

    Research on symmetry detection focuses on identifying and detecting new types of symmetry. The paper presents an algorithm that is capable of detecting any type of permutation-based symmetry, including many types for which there are no existing algorithms. General symmetry detection is library-based, but symmetries that can be parameterized, (i.e. total, partial, rotational, and dihedral symmetry), can be detected without using libraries. In many cases it is faster than existing techniques. Furthermore, it is simpler than most existing techniques, and can easily be incorporated into existing software. The algorithm can also be used with virtually any type of matrix-based symmetry, including conjugate symmetry.

  3. Needs of Non-Energy Focused Contractors

    SciTech Connect

    Liakus, C.

    2012-12-01

    To better understand the informational needs of non-energy focused contractors, including what information they need to motivate them to become energy-focused, the BARA team studied the type of information provided by the national programs, trade associations, and manufacturers that were researched for the related technical report: Effective Communication of Energy Efficiency. While that report focused on the delivery method, format, and strategy of the information, this study examines the content being put forward.

  4. Unstable resonators with a distributed focusing gain.

    PubMed

    Ferguson, T R

    1994-08-20

    The geometrical optics approximation is used to form a model of axisymmetric unstable resonators having distributed focus, gain, and loss. A tapered reflectivity feedback mirror is included. The rate equations for propagation through the focusing gain medium are derived. A unique grid is found for propagation without interpolation along eigenrays in each direction. Numerical examples show the effects of distributed gain and focus on the axial and transverse intensity distributions. PMID:20935986

  5. Needs of Non Energy-Focused Contractors

    SciTech Connect

    Liaukus, C.

    2012-12-01

    To better understand the informational needs of non energy-focused contractors, including what information they need to motivate them to become energy-focused, the BARA team studied the type of information provided by the national programs, trade associations, and manufacturers that were researched for the related technical report: Effective Communication of Energy Efficiency. While that report focused on the delivery method, format, and strategy of the information, this study examines the content being put forward.

  6. Numerical simulation of spherical plasma focus diode

    NASA Astrophysics Data System (ADS)

    Jiang, W.; Masugata, K.; Yatsui, K.

    1995-06-01

    A self-magnetically insulated, three-dimensionally-focused ion-beam diode, spherical plasma focus diode (SPFD), is studied by numerical simulation using a two-dimensional, electromagnetic, relativistic particle-in-cell computer code. The calculated results of the diode impedance, the ion-current efficiency, and the focusing characteristics of the ion beam are presented. These results, except the data of the ion-beam current, are in good agreement with the experimental results.

  7. Automatic focusing system of BSST in Antarctic

    NASA Astrophysics Data System (ADS)

    Tang, Peng-Yi; Liu, Jia-Jing; Zhang, Guang-yu; Wang, Jian

    2015-10-01

    Automatic focusing (AF) technology plays an important role in modern astronomical telescopes. Based on the focusing requirement of BSST (Bright Star Survey Telescope) in Antarctic, an AF system is set up. In this design, functions in OpenCV is used to find stars, the algorithm of area, HFD or FWHM are used to degree the focus metric by choosing. Curve fitting method is used to find focus position as the method of camera moving. All these design are suitable for unattended small telescope.

  8. FEMP Focus: 2011 Volume 20 Issue 1

    SciTech Connect

    2011-04-05

    Department of Energy (DOE); Federal Energy Management Program; FEMP Focus Newsletter; December 2010; Alternative Financing, Guidance Documents, Recovery Act Technical Assistance, Training, Energy Awareness

  9. Low voltage operation of plasma focus.

    PubMed

    Shukla, Rohit; Sharma, S K; Banerjee, P; Das, R; Deb, P; Prabahar, T; Das, B K; Adhikary, B; Shyam, A

    2010-08-01

    Plasma foci of compact sizes and operating with low energies (from tens of joules to few hundred joules) have found application in recent years and have attracted plasma-physics scientists and engineers for research in this direction. We are presenting a low energy and miniature plasma focus which operates from a capacitor bank of 8.4 muF capacity, charged at 4.2-4.3 kV and delivering approximately 52 kA peak current at approximately 60 nH calculated circuit inductance. The total circuit inductance includes the plasma focus inductance. The reported plasma focus operates at the lowest voltage among all reported plasma foci so far. Moreover the cost of capacitor bank used for plasma focus is nearly 20 U.S. dollars making it very cheap. At low voltage operation of plasma focus, the initial breakdown mechanism becomes important for operation of plasma focus. The quartz glass tube is used as insulator and breakdown initiation is done on its surface. The total energy of the plasma focus is approximately 75 J. The plasma focus system is made compact and the switching of capacitor bank energy is done by manual operating switch. The focus is operated with hydrogen and deuterium filled at 1-2 mbar. PMID:20815602

  10. Low voltage operation of plasma focus

    SciTech Connect

    Shukla, Rohit; Sharma, S. K.; Banerjee, P.; Das, R.; Deb, P.; Prabahar, T.; Das, B. K.; Adhikary, B.; Shyam, A.

    2010-08-15

    Plasma foci of compact sizes and operating with low energies (from tens of joules to few hundred joules) have found application in recent years and have attracted plasma-physics scientists and engineers for research in this direction. We are presenting a low energy and miniature plasma focus which operates from a capacitor bank of 8.4 {mu}F capacity, charged at 4.2-4.3 kV and delivering approximately 52 kA peak current at approximately 60 nH calculated circuit inductance. The total circuit inductance includes the plasma focus inductance. The reported plasma focus operates at the lowest voltage among all reported plasma foci so far. Moreover the cost of capacitor bank used for plasma focus is nearly 20 U.S. dollars making it very cheap. At low voltage operation of plasma focus, the initial breakdown mechanism becomes important for operation of plasma focus. The quartz glass tube is used as insulator and breakdown initiation is done on its surface. The total energy of the plasma focus is approximately 75 J. The plasma focus system is made compact and the switching of capacitor bank energy is done by manual operating switch. The focus is operated with hydrogen and deuterium filled at 1-2 mbar.

  11. Final focus system for high intensity beams

    SciTech Connect

    Henestroza, E.; Bieniosek, F.M.; Eylon, S.; Roy, P.K.; Yu, S.S.

    2003-05-01

    The NTX experiment at the Heavy Ion Fusion Virtual National Laboratory is exploring the performance of neutralized final focus systems for high perveance heavy ion beams. The NTX final focus system produces a converging beam at the entrance to the neutralized drift section where it focuses to a small spot. The final focus lattice consists of four pulsed quadrupole magnets. The main issues are the control of emittance growth due to high order fields from magnetic multipoles and image fields. We will present experimental results from NTX on beam envelope and phase space distributions, and compare these results with particle simulations using the particle-in-cell code WARP.

  12. Regulatory focus affects physician risk tolerance.

    PubMed

    Veazie, Peter J; McIntosh, Scott; Chapman, Benjamin P; Dolan, James G

    2014-01-01

    Risk tolerance is a source of variation in physician decision-making. This variation, if independent of clinical concerns, can result in mistaken utilization of health services. To address such problems, it will be helpful to identify nonclinical factors of risk tolerance, particularly those amendable to intervention-regulatory focus theory suggests such a factor. This study tested whether regulatory focus affects risk tolerance among primary care physicians. Twenty-seven primary care physicians were assigned to promotion-focused or prevention-focused manipulations and compared on the Risk Taking Attitudes in Medical Decision Making scale using a randomization test. Results provide evidence that physicians assigned to the promotion-focus manipulation adopted an attitude of greater risk tolerance than the physicians assigned to the prevention-focused manipulation (p = 0.01). The Cohen's d statistic was conventionally large at 0.92. Results imply that situational regulatory focus in primary care physicians affects risk tolerance and may thereby be a nonclinical source of practice variation. Results also provide marginal evidence that chronic regulatory focus is associated with risk tolerance (p = 0.05), but the mechanism remains unclear. Research and intervention targeting physician risk tolerance may benefit by considering situational regulatory focus as an explanatory factor.

  13. Teaching Focus Group Interviewing: Benefits and Challenges

    ERIC Educational Resources Information Center

    George, Molly

    2013-01-01

    Focus group interviewing is widely used by academic and applied researchers. Given the popularity and strengths of this method, it is surprising how rarely focus group interviewing is taught in the undergraduate classroom and how few resources exist to support instructors who wish to train students to use this technique. This article fills the gap…

  14. Inside out: Focusing as a Therapeutic Modality

    ERIC Educational Resources Information Center

    Wagner, Katje

    2006-01-01

    The author explores Focusing (E. Gendlin, 1959, 1961, 1962, 1964, 1967, 1968, 1981, 1989, 1996, 2004) as a psychotherapeutic modality and presents background that led to the development of Focusing, its rationale and theoretical orientation, and supporting research. The author also provides a detailed and experiential illustration of the…

  15. School-focused Inservice: Descriptions and Discussion.

    ERIC Educational Resources Information Center

    Howey, Kenneth R., Ed.; And Others

    The characteristics and structures of school-focused inservice teacher education are explored by educators and researchers in 16 essays. An introductory article gives the rationale for more and better school-focused inservice education, particularly because of the Education for All Handicapped Children Act (Public Law 94-142). School-focused…

  16. Accuracy of Information Processing under Focused Attention.

    ERIC Educational Resources Information Center

    Bastick, Tony

    This paper reports the results of an experiment on the accuracy of information processing during attention focused arousal under two conditions: single estimation and double estimation. The attention of 187 college students was focused by a task requiring high level competition for a monetary prize ($10) under severely limited time conditions. The…

  17. Inclusive Focus Particles in English and Korean

    ERIC Educational Resources Information Center

    Kang, Sang-gu

    2011-01-01

    When discussing focus particles, it has been common practice to rely on the dichotomy of inclusive vs. exclusive particles, "a la" Konig (1991). Inclusive focus particles are often further divided into scalar particles, such as "also", "too", and "either", and non-scalar particles, such as "even". In this thesis, I advance a comparative analysis…

  18. ION BEAM FOCUSING MEANS FOR CALUTRON

    DOEpatents

    Backus, J.G.

    1959-06-01

    An ion beam focusing arrangement for calutrons is described. It provides a virtual focus of origin for the ion beam so that the ions may be withdrawn from an arc plasma of considerable width providing greater beam current and accuracy. (T.R.H.)

  19. How I Learned to Conduct Focus Groups

    ERIC Educational Resources Information Center

    Del Rio-Roberts, Maribel

    2011-01-01

    The use of focus groups may provide researchers with important insights into research questions via participant discussion and interaction. As a human services practitioner and researcher, I became interested in learning how to conduct focus groups in order to apply these steps to my research and gain valuable insights about the human experience…

  20. Plasma lenses for focusing relativistic electron beams

    SciTech Connect

    Govil, R.; Wheeler, S.; Leemans, W.

    1997-04-01

    The next generation of colliders require tightly focused beams with high luminosity. To focus charged particle beams for such applications, a plasma focusing scheme has been proposed. Plasma lenses can be overdense (plasma density, n{sub p} much greater than electron beam density, n{sub b}) or underdense (n{sub p} less than 2 n{sub b}). In overdense lenses the space-charge force of the electron beam is canceled by the plasma and the remaining magnetic force causes the electron beam to self-pinch. The focusing gradient is nonlinear, resulting in spherical aberrations. In underdense lenses, the self-forces of the electron beam cancel, allowing the plasma ions to focus the beam. Although for a given beam density, a uniform underdense lens produces smaller focusing gradients than an overdense lens, it produces better beam quality since the focusing is done by plasma ions. The underdense lens can be improved by tapering the density of the plasma for optimal focusing. The underdense lens performance can be enhanced further by producing adiabatic plasma lenses to avoid the Oide limit on spot size due to synchrotron radiation by the electron beam. The plasma lens experiment at the Beam Test Facility (BTF) is designed to study the properties of plasma lenses in both overdense and underdense regimes. In particular, important issues such as electron beam matching, time response of the lens, lens aberrations and shot-to-shot reproducibility are being investigated.

  1. On FOCUS: Photographs and Writings by Students.

    ERIC Educational Resources Information Center

    Strohmeyer, Beatriz; McGrail, Loren

    Project FOCUS is aimed at enhancing literacy education for non-native speakers of English through the use of photography. It was offered as an elective course within a family literacy program for Hispanic adults. This collection of writings and photographs originated in the program. The collection begins with an overview of Project FOCUS, personal…

  2. Focus Groups with Linguistically Marginalized Populations.

    ERIC Educational Resources Information Center

    Pardi, Marco M.

    The focus group method has rapidly gained credibility among researchers in many fields, including public health researchers. The increased use of focus groups by public health researchers has underscored the demonstrable need for the capacity to apply this method of research among populations with limited abilities in or cultural resistance to…

  3. Attentional Focus Effects in Balance Acrobats

    ERIC Educational Resources Information Center

    Wulf, Gabriele

    2008-01-01

    Performing and learning motor skills has been shown to be enhanced if the performer adopts an external relative to internal focus (or no focus) of attention (Wulf, 2007). The present study examined the generalizability of this effect to top-level performers (balance acrobats). Participants performed a balance task (standing on an inflated rubber…

  4. Identifying Information Focuses in Listening Comprehension

    ERIC Educational Resources Information Center

    Zhang, Hong-yan

    2011-01-01

    The study explains the process of learners' listening comprehension within Halliday's information theory in functional grammar, including the skills of identifying focuses while listening in college English teaching. Identifying information focuses in listening is proved to improve the students' communicative listening ability by the means of a…

  5. Using Focused Conversation in the Classroom

    ERIC Educational Resources Information Center

    Spee, James C.

    2005-01-01

    Focused conversation is a method of collecting observations, emotions, interpretations, and decisions from groups that have shared a significant experience. This article reports how the author used focused conversation to discuss the events of September 11 with students in three sections of a master's-level organizational change class in the week…

  6. Focus Group Report: Seminar in College Teaching.

    ERIC Educational Resources Information Center

    Chang, Glenna C.; And Others

    This paper presents the report of a University of Maryland focus group evaluating a seminar in teaching designed for undergraduate teaching fellows in engineering. The course's purpose was to provide the fellows the opportunity to apply teaching theory to practice. Focus groups were conducted in order to evaluate the course and the teaching…

  7. Scanning and focusing mechanisms of METEOSAT radiometer

    NASA Technical Reports Server (NTRS)

    Jouan, J.

    1977-01-01

    Two mechanisms, both of screw-jack type are described. The scanning mechanism, an oil lubricated and sealed unit drives and accurately positions the telescope of the METEOSAT radiometer. The dry lubricated focusing mechanism is used to adjust the focus of this telescope. The METEOSAT program is nearly completed, and the first flight model will be launched at the end of the year.

  8. Focused force angioplasty Theory and application

    SciTech Connect

    Solar, Ronald J.; Ischinger, Thomas A

    2003-03-01

    Focused force angioplasty is a technique in which the forces resulting from inflating an angioplasty balloon in a stenosis are concentrated and focused at one or more locations within the stenosis. While the technique has been shown to be useful in resolving resistant stenoses, its real value may be in minimizing the vascular trauma associated with balloon angioplasty and subsequently improving the outcome.

  9. Using Focus Group Research in Public Relations.

    ERIC Educational Resources Information Center

    Grunig, Larissa A.

    1990-01-01

    Analyzes a recent instance of focus group research applied to a public relations case (rather than a marketing case). Reviews the advantages and disadvantages of this qualitative method, and describes the case of a county department of mental health relying on focus group research to help plan a program aimed at reducing the stigma of mental…

  10. Attentional Focusing Instructions and Force Production

    PubMed Central

    Marchant, David C.

    2010-01-01

    Research progress assessing the role of attentional focusing instructions on skill acquisition and performance has lead researchers to apply this approach to force production tasks. Initial converging evidence indicates that force production tasks are sensitive to verbal instruction; externally focused instructions (onto movement outcomes, or onto the object force is being exerted against) are shown to be more beneficial than internally focused instructions (focusing attention onto the movements being executed). These benefits are observed for maximal and accurate force production, as well as the maintenance of force production in prolonged tasks. A range of mechanisms are identified supporting the proposal that an external focus promotes movement efficiency in line with energy and effort conservation. Future research is required to assess how this developing body of work interacts with the broader understanding of psychological and physiological factors implicated in the effective production, maintenance, and limitation of maximal or sub-maximal forces. PMID:21833266

  11. Improvement of focus accuracy on processed wafer

    NASA Astrophysics Data System (ADS)

    Higashibata, Satomi; Komine, Nobuhiro; Fukuhara, Kazuya; Koike, Takashi; Kato, Yoshimitsu; Hashimoto, Kohji

    2013-04-01

    As feature size shrinkage in semiconductor device progress, process fluctuation, especially focus strongly affects device performance. Because focus control is an ongoing challenge in optical lithography, various studies have sought for improving focus monitoring and control. Focus errors are due to wafers, exposure tools, reticles, QCs, and so on. Few studies are performed to minimize the measurement errors of auto focus (AF) sensors of exposure tool, especially when processed wafers are exposed. With current focus measurement techniques, the phase shift grating (PSG) focus monitor 1) has been already proposed and its basic principle is that the intensity of the diffraction light of the mask pattern is made asymmetric by arranging a π/2 phase shift area on a reticle. The resist pattern exposed at the defocus position is shifted on the wafer and shifted pattern can be easily measured using an overlay inspection tool. However, it is difficult to measure shifted pattern for the pattern on the processed wafer because of interruptions caused by other patterns in the underlayer. In this paper, we therefore propose "SEM-PSG" technique, where the shift of the PSG resist mark is measured by employing critical dimension-scanning electron microscope (CD-SEM) to measure the focus error on the processed wafer. First, we evaluate the accuracy of SEM-PSG technique. Second, by applying the SEM-PSG technique and feeding the results back to the exposure, we evaluate the focus accuracy on processed wafers. By applying SEM-PSG feedback, the focus accuracy on the processed wafer was improved from 40 to 29 nm in 3σ.

  12. Prostate focused ultrasound focal therapy--imaging for the future.

    PubMed

    Rouvière, Olivier; Gelet, Albert; Crouzet, Sébastien; Chapelon, Jean-Yves

    2012-12-01

    Treatment of prostate cancer using high-intensity focused ultrasound (HIFU) focal therapy will become a reliable treatment option only if several conditions are fulfilled. These conditions concern patient selection, assessment of the tumour location and aggressiveness, evaluation of target tissue destruction, and detection of local recurrence or appearance of new tumours. Regarding patient selection, standard transrectal biopsies are not accurate enough and, although perineal template biopsies can detect tumours, they are invasive, expensive procedures, and there is a risk of incidental detection of insignificant cancers. In turn, multiparametric MRI is accurate for detecting and localizing high-grade (Gleason score ≥7) cancers and may provide non-invasive assessment of tumour aggressiveness. Moreover, contrast-enhanced imaging-ultrasonography or MRI-can assess post-HIFU tissue destruction and provide accurate detection of tumour recurrence, which is a key element for follow up. This Perspectives article will assess whether our current methods for cancer diagnosis, tissue targeting, and treatment follow up are accurate enough to allow the design of robust HIFU focal therapy protocols.

  13. Performance Improvement of Algorithms Based on the Synthetic Aperture Focusing Technique

    NASA Astrophysics Data System (ADS)

    Acevedo, P.; Sotomayor, A.; Moreno, E.

    An analysis to improve the performance of the ultrasonic synthetic aperture focusing technique (SAFT) on a PC platform is presented in this paper. Some useful processing techniques like apodization, dynamic focusing, envelope detection and image composition are used to improve the quality of the image. Finally, results of the algorithm implemented using MATLAB and C/C++ and the respective images are presented

  14. Focus-of-attention for human activity recognition from UAVs

    NASA Astrophysics Data System (ADS)

    Burghouts, G. J.; van Eekeren, A. W. M.; Dijk, J.

    2014-10-01

    This paper presents a system to extract metadata about human activities from full-motion video recorded from a UAV. The pipeline consists of these components: tracking, motion features, representation of the tracks in terms of their motion features, and classification of each track as one of the human activities of interest. We consider these activities: walk, run, throw, dig, wave. Our contribution is that we show how a robust system can be constructed for human activity recognition from UAVs, and that focus-of-attention is needed. We find that tracking and human detection are essential for robust human activity recognition from UAVs. Without tracking, the human activity recognition deteriorates. The combination of tracking and human detection is needed to focus the attention on the relevant tracks. The best performing system includes tracking, human detection and a per-track analysis of the five human activities. This system achieves an average accuracy of 93%. A graphical user interface is proposed to aid the operator or analyst during the task of retrieving the relevant parts of video that contain particular human activities. Our demo is available on YouTube.

  15. Neutron and Ion Beams Emitted from Plasma Focus (112.5 J) Device

    NASA Astrophysics Data System (ADS)

    El-Aragi M., G.

    2010-02-01

    Preliminary results of recent experiments performed within the Mather-type 112.5 J plasma focus device are presented. The ion beams from the focus device operated with deuterium filling at 1 mbar were registered using CR-39 solid state nuclear track detectors (SSNTD) and a Faraday cup detector for time-resolved measurements. The time-resolved neutron emission from the focus region measurements was detected with a photomultiplier tube (IP-28) optically coupled with a plastic scintillator NE 102.

  16. Tanks Focus Area annual report FY2000

    SciTech Connect

    2000-12-01

    The U.S. Department of Energy (DOE) continues to face a major radioactive waste tank remediation effort with tanks containing hazardous and radioactive waste resulting from the production of nuclear materials. With some 90 million gallons of waste in the form of solid, sludge, liquid, and gas stored in 287 tanks across the DOE complex, containing approximately 650 million curies, radioactive waste storage tank remediation is the nation's highest cleanup priority. Differing waste types and unique technical issues require specialized science and technology to achieve tank cleanup in an environmentally acceptable manner. Some of the waste has been stored for over 50 years in tanks that have exceeded their design lives. The challenge is to characterize and maintain these contents in a safe condition and continue to remediate and close each tank to minimize the risks of waste migration and exposure to workers, the public, and the environment. In 1994, the DOE's Office of Environmental Management (EM) created a group of integrated, multiorganizational teams focusing on specific areas of the EM cleanup mission. These teams have evolved into five focus areas managed within EM's Office of Science and Technology (OST): Tanks Focus Area (TFA); Deactivation and Decommissioning Focus Area; Nuclear Materials Focus Area; Subsurface Contaminants Focus Area; and Transuranic and Mixed Waste Focus Area.

  17. Deep-Focusing Time-Distance Helioseismology

    NASA Technical Reports Server (NTRS)

    Duvall, T. L., Jr.; Jensen, J. M.; Kosovichev, A. G.; Birch, A. C.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    Much progress has been made by measuring the travel times of solar acoustic waves from a central surface location to points at equal arc distance away. Depth information is obtained from the range of arc distances examined, with the larger distances revealing the deeper layers. This method we will call surface-focusing, as the common point, or focus, is at the surface. To obtain a clearer picture of the subsurface region, it would, no doubt, be better to focus on points below the surface. Our first attempt to do this used the ray theory to pick surface location pairs that would focus on a particular subsurface point. This is not the ideal procedure, as Born approximation kernels suggest that this focus should have zero sensitivity to sound speed inhomogeneities. However, the sensitivity is concentrated below the surface in a much better way than the old surface-focusing method, and so we expect the deep-focusing method to be more sensitive. A large sunspot group was studied by both methods. Inversions based on both methods will be compared.

  18. Laser focus compensating sensing and imaging device

    DOEpatents

    Vann, C.S.

    1993-08-31

    A laser focus compensating sensing and imaging device permits the focus of a single focal point of different frequency laser beams emanating from the same source point. In particular it allows the focusing of laser beam originating from the same laser device but having differing intensities so that a low intensity beam will not convert to a higher frequency when passing through a conversion crystal associated with the laser generating device. The laser focus compensating sensing and imaging device uses a Cassegrain system to fold the lower frequency, low intensity beam back upon itself so that it will focus at the same focal point as a high intensity beam. An angular tilt compensating lens is mounted about the secondary mirror of the Cassegrain system to assist in alignment. In addition cameras or CCD's are mounted with the primary mirror to sense the focused image. A convex lens is positioned co-axial with the Cassegrain system on the side of the primary mirror distal of the secondary for use in aligning a target with the laser beam. A first alternate embodiment includes a Cassegrain system using a series of shutters and an internally mounted dichroic mirror. A second alternate embodiment uses two laser focus compensating sensing and imaging devices for aligning a moving tool with a work piece.

  19. Laser focus compensating sensing and imaging device

    DOEpatents

    Vann, Charles S.

    1993-01-01

    A laser focus compensating sensing and imaging device permits the focus of a single focal point of different frequency laser beams emanating from the same source point. In particular it allows the focusing of laser beam originating from the same laser device but having differing intensities so that a low intensity beam will not convert to a higher frequency when passing through a conversion crystal associated with the laser generating device. The laser focus compensating sensing and imaging device uses a cassegrain system to fold the lower frequency, low intensity beam back upon itself so that it will focus at the same focal point as a high intensity beam. An angular tilt compensating lens is mounted about the secondary mirror of the cassegrain system to assist in alignment. In addition cameras or CCD's are mounted with the primary mirror to sense the focused image. A convex lens is positioned co-axial with the cassegrain system on the side of the primary mirror distal of the secondary for use in aligning a target with the laser beam. A first alternate embodiment includes a cassegrain system using a series of shutters and an internally mounted dichroic mirror. A second alternate embodiment uses two laser focus compensating sensing and imaging devices for aligning a moving tool with a work piece.

  20. Fraud Detection in Healthcare

    SciTech Connect

    Chandola, Varun; Schryver, Jack C; Sukumar, Sreenivas R

    2015-01-01

    We discuss the problem of fraud detection in healthcare in this chapter. Given the recent scrutiny of the ineciencies in the US healthcare system, identifying fraud has been on the forefront of the eorts towards reducing the healthcare costs. In this chapter we will focus on understanding the issue of healthcare fraud in detail, and review methods that have been proposed in the literature to combat this issue using data driven approach.

  1. Focused Ion beam source method and Apparatus

    SciTech Connect

    Pellin, Michael J.; Lykke, Keith R.; Lill, Thorsten B.

    1998-08-17

    A focused ion beam having a cross section of submicron diameter, a high ion current, and a narrow energy range is generated from a target comprised of particle source material by laser ablation. The method involves directing a laser beam having a cross section of critical diameter onto the target, producing a cloud of laser ablated particles having unique characteristics, and extracting and focusing a charged particle beam from the laser ablated cloud. The method is especially suited for producing focused ion beams for semiconductor device analysis and modification.

  2. MRI-guided focused ultrasound treatments.

    PubMed

    Hynynen, Kullervo

    2010-02-01

    Focused ultrasound (FUS) allows noninvasive focal delivery of energy deep into soft tissues. The focused energy can be used to modify and eliminate tissue for therapeutic purposes while the energy delivery is targeted and monitored using magnetic resonance imaging (MRI). MRI compatible methods to deliver these exposures have undergone rapid development over the past 10 years such that clinical treatments are now routinely performed. This paper will review the current technical and clinical status of MRI-guided focused ultrasound therapy and discuss future research and development opportunities.

  3. Focused ion beam source method and apparatus

    DOEpatents

    Pellin, Michael J.; Lykke, Keith R.; Lill, Thorsten B.

    2000-01-01

    A focused ion beam having a cross section of submicron diameter, a high ion current, and a narrow energy range is generated from a target comprised of particle source material by laser ablation. The method involves directing a laser beam having a cross section of critical diameter onto the target, producing a cloud of laser ablated particles having unique characteristics, and extracting and focusing a charged particle beam from the laser ablated cloud. The method is especially suited for producing focused ion beams for semiconductor device analysis and modification.

  4. Aerodynamic Focusing Of High-Density Aerosols

    SciTech Connect

    Ruiz, D. E.; Fisch, Nathaniel

    2014-02-24

    High-density micron-sized particle aerosols might form the basis for a number of applications in which a material target with a particular shape might be quickly ionized to form a cylindrical or sheet shaped plasma. A simple experimental device was built in order to study the properties of high-density aerosol focusing for 1 m silica spheres. Preliminary results recover previous findings on aerodynamic focusing at low densities. At higher densities, it is demonstrated that the focusing properties change in a way which is consistent with a density dependent Stokes number.

  5. An auto-focusing system for white light microscopic measurement

    NASA Astrophysics Data System (ADS)

    Chang, Ming; Deka, Juti Rani; Chen, Pei Jung; Chen, Yu Kuan; Cui, Changcai

    2008-12-01

    With the rapid development of semiconductor technology the demand for high resolution measuring system is evolving at an ever-increasing pace. Microscope was initially used to detect the defect by connecting charge couple device (CCD) as an auxiliary device. In general, for microscopic measurement human eyes are used to focus on the sample. The adjustment depends on the operator's astute measurement ability, which affected the repeatability and accuracy of the readings. There is a need of high-speed microscope auto focusing system for industrial applications. The present investigation describes about the development of an autofocus system to carry out microscopic measurement more precisely and accurately with less time. The measurement system consists of a light source, two beam splitters, a movable sample stage and a Mirau's interferometer, a photo-detector and 8051 microcontroller (MCU89C51). The light reflected from the sample surface interferes with the light reflected from the reference and produce an interference pattern, which is imaged onto a CCD array. In the setup developed for the autofocus one extra beam splitter is placed in the path of interfered beam to the CCD. The beam splitter is placed at equal distances from the CCD and the photodetector. The focus position is determined from the voltage developed in the photo-detector due to the movement of sample stage of the microscope. The maximum voltage that obtained at the focus position is confirmed with the CCD image. Microcontroller is used to stop the controller at the focus position immediately once the sample stage reaches it. Software is developed to locate the maximum intensity position. The design may autofocus the interferometer within 4mm distance in 1 second. The auto-focusing not only provides enhanced repeatability and accuracy of the results at a faster rate but also minimizes operator involvement.

  6. Viscoelastic effects on electrokinetic particle focusing in a constricted microchannel

    PubMed Central

    Lu, Xinyu; DuBose, John; Joo, Sang Woo; Qian, Shizhi

    2015-01-01

    Focusing suspended particles in a fluid into a single file is often necessary prior to continuous-flow detection, analysis, and separation. Electrokinetic particle focusing has been demonstrated in constricted microchannels by the use of the constriction-induced dielectrophoresis. However, previous studies on this subject have been limited to Newtonian fluids only. We report in this paper an experimental investigation of the viscoelastic effects on electrokinetic particle focusing in non-Newtonian polyethylene oxide solutions through a constricted microchannel. The width of the focused particle stream is found NOT to decrease with the increase in DC electric field, which is different from that in Newtonian fluids. Moreover, particle aggregations are observed at relatively high electric fields to first form inside the constriction. They can then either move forward and exit the constriction in an explosive mode or roll back to the constriction entrance for further accumulations. These unexpected phenomena are distinct from the findings in our earlier paper [Lu et al., Biomicrofluidics 8, 021802 (2014)], where particles are observed to oscillate inside the constriction and not to pass through until a chain of sufficient length is formed. They are speculated to be a consequence of the fluid viscoelasticity effects. PMID:25713690

  7. Introduction to Focus Issue: Mesoscales in Complex Networks

    NASA Astrophysics Data System (ADS)

    Almendral, Juan A.; Criado, Regino; Leyva, Inmaculada; Buldú, Javier M.; Sendiña-Nadal, Irene

    2011-03-01

    Although the functioning of real complex networks is greatly determined by modularity, the majority of articles have focused, until recently, on either their local scale structure or their macroscopical properties. However, neither of these descriptions can adequately describe the important features that complex networks exhibit due to their organization in modules. This Focus Issue precisely presents the state of the art on the study of complex networks at that intermediate level. The reader will find out why this mesoscale level has become an important topic of research through the latest advances carried out to improve our understanding of the dynamical behavior of modular networks. The contributions presented here have been chosen to cover, from different viewpoints, the many open questions in the field as different aspects of community definition and detection algorithms, moduli overlapping, dynamics on modular networks, interplay between scales, and applications to biological, social, and technological fields.

  8. Direct observation of light focusing by single photoreceptor cell nuclei.

    PubMed

    Błaszczak, Zuzanna; Kreysing, Moritz; Guck, Jochen

    2014-05-01

    The vertebrate retina is inverted with respect to its optical function, which requires light to pass through the entire tissue prior to detection. The last significant barrier for photons to overcome is the outer nuclear layer formed by photoreceptor cell (PRC) nuclei. Here we experimentally characterise the optical properties of PRC nuclei using bright-field defocusing microscopy to capture near-field intensity distributions behind individual nuclei. We find that some nuclei efficiently focus incident light confirming earlier predictions based on comparative studies of chromatin organisation in nocturnal and diurnal mammals. The emergence of light focusing during the development of mouse nuclei highlights the acquired nature of the observed lens-like behaviour. Optical characterisation of these nuclei is an important first step towards an improved understanding of how light transmission through the retina is influenced by its constituents.

  9. Introduction to focus issue: mesoscales in complex networks.

    PubMed

    Almendral, Juan A; Criado, Regino; Leyva, Inmaculada; Buldú, Javier M; Sendiña-Nadal, Irene

    2011-03-01

    Although the functioning of real complex networks is greatly determined by modularity, the majority of articles have focused, until recently, on either their local scale structure or their macroscopical properties. However, neither of these descriptions can adequately describe the important features that complex networks exhibit due to their organization in modules. This Focus Issue precisely presents the state of the art on the study of complex networks at that intermediate level. The reader will find out why this mesoscale level has become an important topic of research through the latest advances carried out to improve our understanding of the dynamical behavior of modular networks. The contributions presented here have been chosen to cover, from different viewpoints, the many open questions in the field as different aspects of community definition and detection algorithms, moduli overlapping, dynamics on modular networks, interplay between scales, and applications to biological, social, and technological fields. PMID:21456843

  10. EDITORIAL: Focus on Micro- and Nanofluidics FOCUS ON MICRO- AND NANOFLUIDICS

    NASA Astrophysics Data System (ADS)

    Ajdari, Armand; Stone, Howard A.

    2009-07-01

    This focus issue of New Journal of Physics concentrates on recent developments in microfluidics, and related small-scale flow themes. This subject touches on many areas with the common element that they are engaged with understanding, measuring or manipulating flows at the scale of a few hundred microns or smaller. Microfluidics is of interest to many scientists and engineers from many disciplines because it is a toolbox from which they can investigate basic questions in their respective fields. In particular, the field has led to new studies of small-scale fluid flows, especially those dominated by surface effects, which is crucial for understanding electrokinetics, chemical reactions and phase changes, and multiphase systems, including those involving dispersed liquid and gas phases, suspended particles, cells, vesicles, capsules, etc. The lower length scale of these kinds of flows concerns nanoscale manipulation of objects such as DNA or nanoparticles, nanofabrication of surfaces, studies of the flow within nanometers of substrates, etc. Microfluidics has also given rise to technologies because it enables design and implementation of new devices for sensing, detection, measurement, materials characterization, combinatorial discovery, cellular-scale manipulation, miniaturization of reactors, etc. The fact that these systems are small, cheap, physically flexible, portable, multifunctional, and, when they are working, produce measurements quickly, offers many new avenues for innovation. In this issue we highlight contributions from around the world that explore research directions inspired by the manifold possibilities of microfluidics. In particular, the papers include reports of single-phase flows that are driven by electrical fields, so-called electrokinetics. Although the field has its origins in the 19th century, if not even earlier, new theoretical ideas are required to understand dynamics close to charged surfaces, and new applications of the basic ideas are

  11. A Week-Long Focus on Development.

    ERIC Educational Resources Information Center

    Miller, Stuart; Ross, Judy

    1999-01-01

    Presents a way to dispel common misconceptions about the Third World by organizing a schoolwide event that focuses on the successes of people in developing nations, and the lessons students can learn from their experiences and achievements. (CCM)

  12. A focus on shape coexistence in nuclei

    NASA Astrophysics Data System (ADS)

    Wood, J. L.; Heyde, K.

    2016-02-01

    The present collection of articles focuses on new directions and developments under the title of shape coexistence in nuclei, following our 2011 Reviews of Modern Physics article (K Heyde and J L Wood).

  13. Social Work Intervention Focused on Transitions

    ClinicalTrials.gov

    2014-09-04

    Study Focus: 30-day Rehospitalizations Among At-risk Older Adults Randomized to a Social Work-driven Care Transitions Intervention; Heart Disease; Diabetes; Hypertension; Cancer; Depression; Asthma; Chronic Heart Failure; Chronic Obstructive Pulmonary Disease; Stroke

  14. Apparatus for focusing flowing gas streams

    DOEpatents

    Nogar, N.S.; Keller, R.A.

    1985-05-20

    Apparatus for focusing gas streams. The principle of hydrodynamic focusing is applied to flowing gas streams in order to provide sample concentration for improved photon and sample utilization in resonance ionization mass spectrometric analysis. In a concentric nozzle system, gas samples introduced from the inner nozzle into the converging section of the outer nozzle are focused to streams 50-250-..mu..m in diameter. In some cases diameters of approximately 100-..mu..m are maintained over distances of several centimeters downstream from the exit orifice of the outer nozzle. The sheath gas employed has been observed to further provide a protective covering around the flowing gas sample, thereby isolating the flowing gas sample from possible unwanted reactions with nearby surfaces. A single nozzle variation of the apparatus for achieving hydrodynamic focusing of gas samples is also described.

  15. Hydrodynamic focusing of a particle flux

    SciTech Connect

    Makhviladze, G.M.; Melikhov, O.I.; Nikolova, I.P.

    1995-12-01

    Based on numerical integration of the equations of mechanics of multiphase media, an effect of focusing of a particle flux generated by a source located on the upper wall of a closed vessel has been revealed and investigated.

  16. Regulatory focus in predictions about others.

    PubMed

    Woltin, Karl-Andrew; Yzerbyt, Vincent

    2015-03-01

    Based on social projection research, four studies investigated whether people rely on their own regulatory focus when making predictions about others. Chronic (Study 1) and induced (Study 2) regulatory focus shaped estimations of others' strategic promotion or prevention inclinations and choices between enriched (fitting promotion) and impoverished options (fitting prevention). Providing indirect process evidence via boundary conditions, participants only relied on their induced regulatory focus in predictions of others' inclinations to seek romantic alternatives to the extent that this did not run counter to stereotypic gender beliefs (Study 3). In addition, participants only relied on their induced regulatory focus in preference predictions concerning promotion and prevention products when they lacked idiosyncratic target knowledge (Study 4). These effects were not mediated by mood, judgment-certainty, perceived task-enjoyment, or task-difficulty. Implications of these findings for social projection research as well as possible interpersonal consequences are delineated.

  17. Two-axis sagittal focusing monochromator

    SciTech Connect

    Haas, Edwin G; Stelmach, Christopher; Zhong, Zhong

    2014-05-13

    An x-ray focusing device and method for adjustably focusing x-rays in two orthogonal directions simultaneously. The device and method can be operated remotely using two pairs of orthogonal benders mounted on a rigid, open frame such that x-rays may pass through the opening in the frame. The added x-ray flux allows significantly higher brightness from the same x-ray source.

  18. Results from the final focus test beam

    SciTech Connect

    Burke, D.L.; Final Focus Test Beam Collaboration

    1994-07-01

    first experimental results from the Final Focus Test Beam (FFTB) are given in this report. The FFTB has been constructed as a prototype for the final focus system of a future TeV-scale electron-positron linear collider. The vertical dimension of the 47 GeV electron beam form the SLAC linac has been reduced at the focal point of the FFTB by a demagnification of 320 to a beam height of approximately 70 nanometers.

  19. Molecular focusing and alignment with plasmon fields.

    PubMed

    Artamonov, Maxim; Seideman, Tamar

    2010-12-01

    We show the possibility of simultaneously aligning molecules and focusing their center-of-mass motion near a metal nanoparticle in the field intensity gradient created by the surface plasmon enhancement of incident light. The rotational motion is described quantum mechanically while the translation is treated classically. The effects of the nanoparticle shape on the alignment and focusing are explored. Our results carry interesting implications to the field of molecular nanoplasmonics and suggest several potential applications in nanochemistry.

  20. Fast and Adaptive Auto-focusing Microscope

    NASA Astrophysics Data System (ADS)

    Obara, Takeshi; Igarashi, Yasunobu; Hashimoto, Koichi

    Optical microscopes are widely used in biological and medical researches. By using the microscope, we can observe cellular movements including intracellular ions and molecules tagged with fluorescent dyes at a high magnification. However, a freely motile cell easily escapes from a 3D field of view of the typical microscope. Therefore, we propose a novel auto-focusing algorithm and develop a auto-focusing and tracking microscope. XYZ positions of a microscopic stage are feedback controlled to focus and track the cell automatically. A bright-field image is used to estimate a cellular position. XY centroids are used to estimate XY positions of the tracked cell. To estimate Z position, we use a diffraction pattern around the cell membrane. This estimation method is so-called Depth from Diffraction (DFDi). However, this method is not robust for individual differences between cells because the diffraction pattern depends on each cellular shape. Therefore, in this study, we propose a real-time correction of DFDi by using 2D Laplacian of an intracellular area as a goodness of the focus. To evaluate the performance of our developed algorithm and microscope, we auto-focus and track a freely moving paramecium. In this experimental result, the paramecium is auto-focused and kept inside the scope of the microscope during 45s. The evaluated focal error is within 5µm, while a length and a thickness of the paramecium are about 200µm and 50µm, respectively.

  1. Applications of on-product diffraction-based focus metrology in logic high volume manufacturing

    NASA Astrophysics Data System (ADS)

    Noyes, Ben F.; Mokaberi, Babak; Bolton, David; Li, Chen; Palande, Ashwin; Park, Kevin; Noot, Marc; Kea, Marc

    2016-03-01

    The integration of on-product diffraction-based focus (DBF) capability into the majority of immersion lithography layers in leading edge logic manufacturing has enabled new applications targeted towards improving cycle time and yield. A CD-based detection method is the process of record (POR) for excursion detection. The drawback of this method is increased cycle time and limited sampling due to CD-SEM metrology capacity constraints. The DBFbased method allows the addition of focus metrology samples to the existing overlay measurements on the integrated metrology (IM) system. The result enables the addition of measured focus to the SPC system, allowing a faster excursion detection method. For focus targeting, the current method involves using a dedicated focus-exposure matrix (FEM) on all scanners, resulting in lengthy analysis times and uncertainty in the best focus. The DBF method allows the measurement to occur on the IM system, on a regular production wafer, and at the same time as the exposure. This results in a cycle time gain as well as a less subjective determination of best focus. A third application aims to use the novel onproduct focus metrology data in order to apply per-exposure focus corrections to the scanner. These corrections are particularly effective at the edge of the wafer, where systematic layer-dependent effects can be removed using DBFbased scanner feedback. This paper will discuss the development of a methodology to accomplish each of these applications in a high-volume production environment. The new focus metrology method, sampling schemes, feedback mechanisms and analysis methods lead to improved focus control, as well as earlier detection of failures.

  2. Methods for Doping Detection.

    PubMed

    Ponzetto, Federico; Giraud, Sylvain; Leuenberger, Nicolas; Boccard, Julien; Nicoli, Raul; Baume, Norbert; Rudaz, Serge; Saugy, Martial

    2016-01-01

    Over the past few years, the World Anti-Doping Agency (WADA) has focused its efforts on detecting not only small prohibited molecules, but also larger endogenous molecules such as hormones, in the view of implementing an endocrinological module in the Athlete Biological Passport (ABP). In this chapter, the detection of two major types of hormones used for doping, growth hormone (GH) and endogenous anabolic androgenic steroids (EAASs), will be discussed: a brief historical background followed by a description of state-of-the-art methods applied by accredited anti-doping laboratories will be provided and then current research trends outlined. In addition, microRNAs (miRNAs) will also be presented as a new class of biomarkers for doping detection. PMID:27348309

  3. Multicenter comparative study of a new ELISA, PLATELIA RABIES II, for the detection and titration of anti-rabies glycoprotein antibodies and comparison with the rapid fluorescent focus inhibition test (RFFIT) on human samples from vaccinated and non-vaccinated people.

    PubMed

    Feyssaguet, M; Dacheux, L; Audry, L; Compoint, A; Morize, J L; Blanchard, I; Bourhy, H

    2007-03-01

    The envelope glycoprotein G of rabies virus induces the production of neutralising antibodies, which are important in protection against rabies. Therefore, titration of anti-envelope glycoprotein antibodies is a good indicator of the degree of immunity in people during anti-rabies treatment or after vaccination. According to the World Health Organization (WHO) guidelines, a booster vaccine dose should be given if the rabies antibody titre falls below 0.5 IU/ml. Titration of anti-rabies antibodies is also useful for plasma centers in the preparation and standardization of human anti-rabies gamma-globulins for therapeutic use and to a lesser extent for the diagnosis of rabies in human sera and cerebrospinal fluid (CSF). This paper presents a new enzyme-linked immunosorbent assay (ELISA), PLATELIA RABIES II, developed for rabies envelope glycoprotein antibody detection or titration and its comparison to the current reference method (RFFIT). The data collected during validation of the test in a multicenter study are analysed to give a sound overall knowledge of the capabilities of the PLATELIA RABIES II, for instance specificity, linearity, accuracy, precision, detection limit and quantitation limit. To this aim, human serum samples from a total of 1348 vaccinated or non-vaccinated people were tested in parallel using the new ELISA and the RFFIT for the presence of anti-rabies antibodies. Data generated indicate a linear relationship across the range of titration between the two methods. The sensitivity reaches 98.6% and the specificity 99.4%. This study indicates that this new ELISA test is as sensitive and specific as the current standardized reference method. The method is simple, safe, rapid and can be considered as a useful alternative to the neutralisation test.

  4. Efficacy of Child-Focused and Parent-Focused Interventions in a Child Anxiety Prevention Study

    ERIC Educational Resources Information Center

    Simon, Ellin; Bogels, Susan Maria; Voncken, Jannie Marisol

    2011-01-01

    This study examined anxiety development in median- (n = 74) and high-anxious children (n = 183) aged 8-13, the effect of parent- and child-focused preventive interventions on child/parental anxiety, and the effect of parental anxiety on child anxiety. High-anxious children were randomized into a parent-focused (n = 69), child-focused (n = 58) or…

  5. Localized harmonic motion imaging for focused ultrasound surgery targeting.

    PubMed

    Curiel, Laura; Hynynen, Kullervo

    2011-08-01

    Recently, an in vivo real-time ultrasound-based monitoring technique that uses localized harmonic motion (LHM) to detect changes in tissues during focused ultrasound surgery (FUS) has been proposed to control the exposure. This technique can potentially be used as well for targeting imaging. In the present study, we evaluated the potential of using LHM to detect changes in stiffness and the feasibility of using it for imaging purposes in phantoms and in vivo tumor detection. A single-element FUS transducer (80 mm focal length, 100 mm diameter, 1.485 MHz) was used for inducing a localized harmonic motion and a separate ultrasound diagnostic transducer excited by a pulser/receiver (5 kHz PRF, 5 MHz) was used to track motion. The motion was estimated using cross-correlation techniques on the acquired radio-frequency (RF) signal. Silicon phantom studies were performed to determine the size of inclusion that was possible to detect using this technique. Inclusions were discerned from the surroundings as a reduction on LHM amplitude and it was possible to depict inclusions as small as 4 mm. The amplitude of the induced LHM was always lower at the inclusions compared with the one obtained at the surroundings. Ten New Zealand rabbits had VX2 tumors implanted on their thighs and LHM was induced and measured at the tumor region. Tumors (as small as 10 mm in length and 4 mm in width) were discerned from the surroundings as a reduction on LHM amplitude.

  6. PROGRESS AND PROBLEMS IN THE APPLICATION OF FOCUSED ULTRASOUND FOR BLOOD-BRAIN BARRIER DISRUPTION

    PubMed Central

    Vykhodtseva, Natalia; McDannold, Nathan; Hynynen, Kullervo

    2008-01-01

    Advances in neuroscience have resulted in the development of new diagnostic and therapeutic agents for potential use in the central nervous system (CNS). However, the ability to deliver the majority of these agents to the brain is limited by the blood–brain barrier (BBB), a specialized structure of the blood vessel wall that hampers transport and diffusion from the blood to the brain. Many CNS disorders could be treated with drugs, enzymes, genes, or large-molecule biotechnological products such as recombinant proteins, if they could cross the BBB. This article reviews the problems of the BBB presence in treating the vast majority of CNS diseases and the efforts to circumvent the BBB through the design of new drugs and the development of more sophisticated delivery methods. Recent advances in the development of noninvasive, targeted drug delivery by MRI-guided ultrasound-induced BBB disruption are also summarized. PMID:18511095

  7. Synthetic Aperture Focusing Technique for the Ultrasonic Evaluation of Friction Stir Welds

    NASA Astrophysics Data System (ADS)

    Lévesque, D.; Dubourg, L.; Mandache, C.; Kruger, S. E.; Lord, M.; Merati, A.; Jahazi, M.; Monchalin, J.-P.

    2008-02-01

    An ultrasonic technique using numerical focusing and processing is presented in this paper for the detection of different types of flaws in friction stir welds (FSW). The data is acquired using immersion ultrasonic technique or laser ultrasonics, while the Synthetic Aperture Focusing Technique (SAFT) is used for numerical focusing. Measurements on the top and far sides of the weld for both lap and butt joints of thin aluminum sheets are investigated. Discontinuities such as wormholes, hooking, lack of penetration and voids are found to be easily detected. The limit of detectability and a comparison with mechanical properties are discussed. Also, the detection of joint line remnants or kissing bonds due to entrapped oxide layers seems possible in lap joint structures using high frequency laser-ultrasonics.

  8. (Aerodynamic focusing of particles and heavy molecules)

    SciTech Connect

    de la Mora, J.F.

    1990-01-08

    By accelerating a gas containing suspended particles or large molecules through a converging nozzle, the suspended species may be focused and therefore used to write fine lines on a surface. Our objective was to study the limits on how narrow this focal region could be as a function of particle size. We find that, for monodisperse particles with masses m{sub p} some 3.6 {times} 10{sup 5} times larger than the molecular mass m of the carrier gas (diameters above some 100{angstrom}), there is no fundamental obstacle to directly write submicron features. However, this conclusion has been verified experimentally only with particles larger than 0.1 {mu}m. Experimental, theoretical and numerical studies on the defocusing role of Brownian motion for very small particles or heavy molecules have shown that high resolution (purely aerodynamic) focusing is impossible with volatile molecules whose masses are typically smaller than 1000 Dalton. For these, the minimal focal diameter after optimization appears to be 5{radical}(m/m{sub p}) times the nozzle diameter d{sub n}. But combinations of focused lasers and aerodynamic focusing appear as promising for direct writing with molecular precursors. Theoretical and numerical schemes capable of predicting the evolution of the focusing beam, including Brownian motion effects, have been developed, although further numerical work would be desirable. 11 refs.

  9. Keeping the Hubble Space Telescope in focus

    NASA Astrophysics Data System (ADS)

    Cox, Colin; Lallo, Matthew

    2012-09-01

    The Hubble Space Telescope is a Ritchie-Chrétien optical design with a main primary concave mirror followed by a convex secondary. The focus is determined by the position of each of these two mirrors. The truss containing them is made of graphite epoxy which has very low thermal expansion. Nevertheless, temperature variations do cause the mirror separation to vary by several microns within an orbit. Additionally, outgassing of water vapor causes a long-term shrinkage which soon after launch in 1990 varied by more than 2 microns per month. This necessitated adjusting the position of the secondary mirror every few months. Currently this rate is greatly reduced and adjustments are needed less than once per year. The focus is monitored monthly to continually assess the need for such adjustments. The measurements have been used to develop models to predict the focus at times between measurements to assist in the analysis of observations. Detailed focus knowledge is of value in photometry, coronagraphy and image deconvolution. The various focus models that have been applied so far are described with an evaluation of their performance. Continuing attempts to refine the model will be discussed.

  10. Task-focused modeling in automated agriculture

    NASA Astrophysics Data System (ADS)

    Vriesenga, Mark R.; Peleg, K.; Sklansky, Jack

    1993-01-01

    Machine vision systems analyze image data to carry out automation tasks. Our interest is in machine vision systems that rely on models to achieve their designed task. When the model is interrogated from an a priori menu of questions, the model need not be complete. Instead, the machine vision system can use a partial model that contains a large amount of information in regions of interest and less information elsewhere. We propose an adaptive modeling scheme for machine vision, called task-focused modeling, which constructs a model having just sufficient detail to carry out the specified task. The model is detailed in regions of interest to the task and is less detailed elsewhere. This focusing effect saves time and reduces the computational effort expended by the machine vision system. We illustrate task-focused modeling by an example involving real-time micropropagation of plants in automated agriculture.

  11. Remote Adjustable focus Raman Spectroscopy Probe

    SciTech Connect

    Schmucker, John E.; Blasi, Raymond J.; Archer, William B.

    1998-07-28

    A remote adjustable focus Raman spectroscopy probe allows for analyzing Raman scattered light from a point of interest external to the probe. An environmental barrier including at least one window separates the probe from the point of interest. An optical tube is disposed adjacent to the environmental barrier and includes along working length compound lens objective next to the window. A beam splitter and a mirror are at the other end. A mechanical means is used to translate the probe body in the X, Y, and Z directions resulting in a variable focus optical apparatus. Laser light is reflected by the beam splitter and directed toward the compound lens objective, then through the window and focused on the point of interest. Raman scattered light is then collected by the compound lens objective and directed through the beam splitter to a mirror. A device for analyzing the light, such as a monochrometer, is coupled to the mirror.

  12. Remote adjustable focus Raman spectroscopy probe

    SciTech Connect

    Schmucker, J.E.; Blasi, R.J.; Archer, W.B.

    1999-12-28

    A remote adjustable focus Raman spectroscopy probe allows for analyzing Raman scattered light from a point of interest external probe. An environmental barrier including at least one window separates the probe from the point of interest. An optical tube is disposed adjacent to the environmental barrier and includes a long working length compound lens objective next to the window. A beam splitter and a mirror are at the other end. A mechanical means is used to translated the prove body in the X, Y, and Z directions resulting in a variable focus optical apparatus. Laser light is reflected by the beam splitter and directed toward the compound lens objective, then through the window and focused on the point of interest. Raman scattered light is then collected by the compound lens objective and directed through the beam splitter to a mirror. A device for analyzing the light, such as a monochrometer, is coupled to the mirror.

  13. Attentional focus in complex skill learning.

    PubMed

    Wulf, G; McNevin, N H; Fuchs, T; Ritter, F; Toole, T

    2000-09-01

    Experiment 1 examined whether it is more advantageous to direct learners' attention to the external effects of their movements relative to other external cues. Two groups of participants hit tennis balls at a target, with one group focusing on the ball coming toward them (antecedent) and the other group focusing on the ball leaving the racket (effect). The effect group demonstrated more effective learning. Experiment 2 examined whether it is more beneficial if the movement effect is related to the movement technique, relative to other movement effects (e.g., outcome). Two groups of participants hit golf balls at a target. The attention of these groups was directed to the club or the ball trajectory, respectively. The club group showed more effective learning than the target group, suggesting that focusing on technique-related effects is more effective. PMID:10999260

  14. Focusing light with a flame lens.

    PubMed

    Michaelis, Max M; Mafusire, Cosmas; Grobler, Jan-Hendrik; Forbes, Andrew

    2013-01-01

    The lens is a well-understood optical component used for focusing light, but is almost exclusively made in the solid-state form and, thus, suffers from optical damage at high powers. Attempts to overcome this through the use of non-solid graded-index media for lensing, for example, heated gasses, have found limited application owing to their long focal lengths. Here we describe the first flame lens, which produces a sharp focus with very little stray light and has a fourfold increase in focal power per unit length over previous gas lenses. Such gas devices remain topical due to their inherent ability to deliver high-power laser beams: our flame lens has a 'damage' threshold that is several orders of magnitude higher than that of most conventional lenses and is immediately repaired after damage for reuse, and thus will be of use in focusing high-irradiance laser beams.

  15. Focusing light with a flame lens

    NASA Astrophysics Data System (ADS)

    Michaelis, Max M.; Mafusire, Cosmas; Grobler, Jan-Hendrik; Forbes, Andrew

    2013-05-01

    The lens is a well-understood optical component used for focusing light, but is almost exclusively made in the solid-state form and, thus, suffers from optical damage at high powers. Attempts to overcome this through the use of non-solid graded-index media for lensing, for example, heated gasses, have found limited application owing to their long focal lengths. Here we describe the first flame lens, which produces a sharp focus with very little stray light and has a fourfold increase in focal power per unit length over previous gas lenses. Such gas devices remain topical due to their inherent ability to deliver high-power laser beams: our flame lens has a ‘damage’ threshold that is several orders of magnitude higher than that of most conventional lenses and is immediately repaired after damage for reuse, and thus will be of use in focusing high-irradiance laser beams.

  16. Remote adjustable focus Raman spectroscopy probe

    DOEpatents

    Schmucker, John E.; Blasi, Raymond J.; Archer, William B.

    1999-01-01

    A remote adjustable focus Raman spectroscopy probe allows for analyzing Raman scattered light from a point of interest external probe. An environmental barrier including at least one window separates the probe from the point of interest. An optical tube is disposed adjacent to the environmental barrier and includes a long working length compound lens objective next to the window. A beam splitter and a mirror are at the other end. A mechanical means is used to translated the prove body in the X, Y, and Z directions resulting in a variable focus optical apparatus. Laser light is reflected by the beam splitter and directed toward the compound lens objective, then through the window and focused on the point of interest. Raman scattered light is then collected by the compound lens objective and directed through the beam splitter to a mirror. A device for analyzing the light, such as a monochrometer, is coupled to the mirror.

  17. Focus groups: nursing staff's experiences using restraints.

    PubMed

    Janelli, L M; Dickerson, S S; Ventura, M R

    1995-11-01

    A phenomenological approach was used to examine nursing staff's experiences using physical restraints. A total of 12 nurses from a tertiary hospital participated in one of three focus groups. Exploring the attitudes of nurses can contribute to a better understanding of how decisions are made concerning restraints. An analysis of the focus group data resulted in a description of the lived experiences of nurses using restraints. Seven themes emerged from the data, one of which reflected that the nurses felt ambiguous about restraints, yet they made judgments and justified their decisions after assessing patient characteristics, environmental safety, and unit traditions. Nurse clinicians could use the focus group method to sensitize themselves to the staff's needs and to allow staff the opportunity to share ideas and to dispel misconceptions about restraints. PMID:7580947

  18. Dynamic focusing in the zebrafish beating heart

    NASA Astrophysics Data System (ADS)

    Andrés-Delgado, L.; Peralta, M.; Mercader, N.; Ripoll, J.

    2016-03-01

    Of the large amount of the animal models available for cardiac research, the zebrafish is extremely valuable due to its transparency during early stages of development. In this work a dual illumination laser sheet microscope with simultaneous dual camera imaging is used to image the beating heart at 200 fps, dynamically and selectively focusing inside the beating heart through the use of a tunable lens. This dual color dynamic focusing enables imaging with cellular resolution at unprecedented high frame rates, allowing 3D imaging of the whole beating heart of embryonic zebrafish.

  19. Stretchable Binary Fresnel Lens for Focus Tuning

    PubMed Central

    Li, Xueming; Wei, Lei; Poelma, René H.; Vollebregt, Sten; Wei, Jia; Urbach, Hendrik Paul; Sarro, Pasqualina M.; Zhang, Guo Qi

    2016-01-01

    This paper presents a tuneable binary amplitude Fresnel lens produced by wafer-level microfabrication. The Fresnel lens is fabricated by encapsulating lithographically defined vertically aligned carbon nanotube (CNT) bundles inside a polydimethyl-siloxane (PDMS) layer. The composite lens material combines the excellent optical absorption properties of the CNT with the transparency and stretchability of the PDMS. By stretching the elastomeric composite in radial direction, the lens focal length is tuned. Good focusing response is demonstrated and a large focus change (≥24%) was achieved by stretching lenses up to 11.4%. PMID:27139747

  20. Ion heating in a plasma focus

    NASA Technical Reports Server (NTRS)

    Hohl, F.; Gary, S. P.

    1974-01-01

    Ion acceleration and heating in a plasma focus were investigated by the numerical integration of the three-dimensional equations of motion. The electric and magnetic fields given were derived from experimental data. The results obtained show that during the collapse phase of focus formation, ions are efficiently heated to temperatures of several keV. During the phase of rapid current reduction, ions are accelerated to large velocities in the axial direction. The results obtained with the model are in general agreement with experimental results.

  1. CY15 Livermore Computing Focus Areas

    SciTech Connect

    Connell, Tom M.; Cupps, Kim C.; D'Hooge, Trent E.; Fahey, Tim J.; Fox, Dave M.; Futral, Scott W.; Gary, Mark R.; Goldstone, Robin J.; Hamilton, Pam G.; Heer, Todd M.; Long, Jeff W.; Mark, Rich J.; Morrone, Chris J.; Shoopman, Jerry D.; Slavec, Joe A.; Smith, David W.; Springmeyer, Becky R; Stearman, Marc D.; Watson, Py C.

    2015-01-20

    The LC team undertook a survey of primary Center drivers for CY15. Identified key drivers included enhancing user experience and productivity, pre-exascale platform preparation, process improvement, data-centric computing paradigms and business expansion. The team organized critical supporting efforts into three cross-cutting focus areas; Improving Service Quality; Monitoring, Automation, Delegation and Center Efficiency; and Next Generation Compute and Data Environments In each area the team detailed high level challenges and identified discrete actions to address these issues during the calendar year. Identifying the Center’s primary drivers, issues, and plans is intended to serve as a lens focusing LC personnel, resources, and priorities throughout the year.

  2. SKEW QUADRUPOLE FOCUSING LATTICES AND APPLICATIONS.

    SciTech Connect

    PARKER,B.

    2001-06-18

    In this paper we revisit using skew quadrupole fields in place of traditional normal upright quadrupole fields to make beam focusing structures. We illustrate by example skew lattice decoupling, dispersion suppression and chromatic correction using the neutrino factory Study-II muon storage ring design. Ongoing BNL investigation of flat coil magnet structures that allow building a very compact muon storage ring arc and other flat coil configurations that might bring significant magnet cost reduction to a VLHC motivate our study of skew focusing.

  3. The changing focus of marine mammal conservation.

    PubMed

    Hofman, R J

    1995-11-01

    Overexploitation has been the principal focus of marine mammal conservation. Less attention has been paid to bycatch in commercial fisheries; entanglement in lost and discarded fishing gear; food shortages owing to climate change and/or overharvesting of essential prey; point and non-point source pollution; and diseases. Also, relatively little attention has been paid to situations where marine mammals pose threats to the existence and human uses of other marine species. As overexploitation is addressed, focus must be shifted to these problems that are no less significant.

  4. Stretchable Binary Fresnel Lens for Focus Tuning

    NASA Astrophysics Data System (ADS)

    Li, Xueming; Wei, Lei; Poelma, René H.; Vollebregt, Sten; Wei, Jia; Urbach, Hendrik Paul; Sarro, Pasqualina M.; Zhang, Guo Qi

    2016-05-01

    This paper presents a tuneable binary amplitude Fresnel lens produced by wafer-level microfabrication. The Fresnel lens is fabricated by encapsulating lithographically defined vertically aligned carbon nanotube (CNT) bundles inside a polydimethyl-siloxane (PDMS) layer. The composite lens material combines the excellent optical absorption properties of the CNT with the transparency and stretchability of the PDMS. By stretching the elastomeric composite in radial direction, the lens focal length is tuned. Good focusing response is demonstrated and a large focus change (≥24%) was achieved by stretching lenses up to 11.4%.

  5. Aspherical lens shapes for focusing synchrotron beams.

    PubMed

    Sanchez del Rio, Manuel; Alianelli, Lucia

    2012-05-01

    Aspherical surfaces required for focusing collimated and divergent synchrotron beams using a single refractive element (lens) are reviewed. The Cartesian oval, a lens shape that produces perfect point-to-point focusing for monochromatic radiation, is studied in the context of X-ray beamlines. Optical surfaces that approximate ideal shapes are compared. Results are supported by ray-tracing simulations. Elliptical lenses, rather than parabolic, are preferred for nanofocusing X-rays because of the higher peak and lower tails in the intensity distribution. Cartesian ovals will improve the gain when using high-demagnification lenses of high numerical aperture. PMID:22514171

  6. Hormone purification by isoelectric focusing in space

    NASA Technical Reports Server (NTRS)

    Bier, M.

    1982-01-01

    The performance of a ground-prototype of an apparatus for recycling isoelectric focusing was evaluated in an effort to provide technology for large scale purification of peptide hormones, proteins, and other biologicals. Special emphasis was given to the effects of gravity on the function of the apparatus and to the determination of potential advantages deriveable from its use in a microgravity environment. A theoretical model of isoelectric focusing sing chemically defined buffer systems for the establishment of the pH gradients was developed. The model was transformed to a form suitable for computer simulations and was used extensively for the design of experimental buffers.

  7. Topicality and Impact in Social Media: Diverse Messages, Focused Messengers

    PubMed Central

    Weng, Lilian; Menczer, Filippo

    2015-01-01

    We have a limited understanding of the factors that make people influential and topics popular in social media. Are users who comment on a variety of matters more likely to achieve high influence than those who stay focused? Do general subjects tend to be more popular than specific ones? Questions like these demand a way to detect the topics hidden behind messages associated with an individual or a keyword, and a gauge of similarity among these topics. Here we develop such an approach to identify clusters of similar hashtags in Twitter by detecting communities in the hashtag co-occurrence network. Then the topical diversity of a user’s interests is quantified by the entropy of her hashtags across different topic clusters. A similar measure is applied to hashtags, based on co-occurring tags. We find that high topical diversity of early adopters or co-occurring tags implies high future popularity of hashtags. In contrast, low diversity helps an individual accumulate social influence. In short, diverse messages and focused messengers are more likely to gain impact. PMID:25710685

  8. EDITORIAL: Focus on High Energy Particle Astronomy FOCUS ON HIGH ENERGY PARTICLE ASTRONOMY

    NASA Astrophysics Data System (ADS)

    Ong, Rene A.; Covault, Corbin E.

    2009-05-01

    another clue to understanding the nature of high-energy objects both within and outside our galaxy. And yet, along with new understandings, we are also faced with new puzzles. Each of the papers in this focus issue presents the field of high-energy particle astronomy from the perspective of a given instrumental approach, corresponding to the current state-of-the-art for a particular class of messenger particle in a given energy range. For gamma-ray astronomy, we have a excellent report by R Johnson and R Mukherjee on results from space-borne telescopes, first from the Compton Gamma Ray Observatory and then from the recently commissioned Fermi Gamma-Ray Space Telescope. The detailed paper by J Hinton describes a wealth of results from several ground-based gamma-ray telescopes using the atmospheric Cherenokov technique. Gamma-ray results and the prospects from air-shower detectors which can provide all-sky monitoring are very well described in a paper by G Sinnis. Larger plans for the future of ground-based gamma-ray astronomy are summarized in a paper by F Krennrich (in preparation). We also include two papers for 'non-photon' particle detection, a summary of the exciting new results for cosmic ray physics by P Sommers and S Westerhoff and an article by K Hoffman describing the astrophysics and capabilities of truly remarkable, large-volume neutrino detectors. For both cosmic rays and neutrinos, the fields seem to be on the threshold of doing astronomy—that is, associating specific detected particles with particular astrophysical objects. Together, the fully operational space- and ground-based gamma-ray observatories and the new large-area experiments for cosmic ray and neutrino detection represent a new era in astronomy. We can be confident that the field of high-energy particle astronomy will continue to rapidly develop as more exciting results from these instruments are reported in the future. Focus on High Energy Particle Astronomy Contents Gamma ray astronomy with

  9. MUSIC algorithms for rebar detection

    NASA Astrophysics Data System (ADS)

    Solimene, Raffaele; Leone, Giovanni; Dell'Aversano, Angela

    2013-12-01

    The MUSIC (MUltiple SIgnal Classification) algorithm is employed to detect and localize an unknown number of scattering objects which are small in size as compared to the wavelength. The ensemble of objects to be detected consists of both strong and weak scatterers. This represents a scattering environment challenging for detection purposes as strong scatterers tend to mask the weak ones. Consequently, the detection of more weakly scattering objects is not always guaranteed and can be completely impaired when the noise corrupting data is of a relatively high level. To overcome this drawback, here a new technique is proposed, starting from the idea of applying a two-stage MUSIC algorithm. In the first stage strong scatterers are detected. Then, information concerning their number and location is employed in the second stage focusing only on the weak scatterers. The role of an adequate scattering model is emphasized to improve drastically detection performance in realistic scenarios.

  10. Study on focusing performance of the twice reflecting laser focusing system

    NASA Astrophysics Data System (ADS)

    Cheng, Fu Qiang; Dou, Zhi Guo

    2011-02-01

    Laser thrusters characterized by feasible application perspective all possess the twice reflecting laser focusing system. Nonetheless, studies on its focusing performance are imperative for the research of flight route of the thruster and haven't been developed yet. Under three different focusing design modes, assisted with optical design software ZEMAX which employing Monte Carlo ray tracing, performance of twice reflecting laser focusing system including focusing performance parameters, radiation intensity distribution and the details of ignition region on the focusing plane are studied comparatively, and the studied two main angular aberrations are beam out-coming aberration from laser source and flying aberration from thruster itself. Studies show even slight aberration will result in steep falling focusing performance and strong deviation of beam spot for any focusing design mode, while different aberrations bring in distinctive falling tendencies and the evolutions of ignition region. It strongly demands the directional precision of laser beam, and the attitude control of laser thruster is indispensable. And it's not recommended that one focusing design mode is superior to another. Which kind of aberration is dominant should be taken into account when choosing focusing mode.

  11. Attentional Focus Effects in Standing Long Jump Performance: Influence of a Broad and Narrow Internal Focus.

    PubMed

    Becker, Kevin A; Smith, Peter J K

    2015-07-01

    The content of instructions that strength coaches give can have a significant impact on how an athlete or client performs. Research on motor learning has shown an advantage of instructions focusing on the effects of movements (external focus) over those focusing on the movements themselves (internal focus) in the performance of motor skills. Internally focused cues are abundant in coaching, therefore the purpose of this study was to test whether some internally focused cues might be more helpful than others. Participants (68) were randomly assigned to either an external focus (EX), broad internal focus (B-IN), narrow internal focus (N-IN), or a control group (CON), and performed 5 standing long jumps. All groups were instructed that the goal was to jump as far as possible. In addition, the EX group was told to "jump as far past the start line as possible." The B-IN group was told to "use your legs." The N-IN group was told to "extend your knees as rapidly as possible," and the CON group received no additional instruction. An analysis of covariance showed that the EX group (198.09 ± 31.89 cm) jumped significantly farther than both the B-IN group (173.74 ± 35.36 cm), p = 0.010 and the N-IN group (178.53 ± 31.17 cm), p = 0.049, with no group different from the CON group. The results suggest that a broad internal focus is no more effective than a narrow internal focus, and that an external focus leads to the greatest jump distance. Strength and conditioning professionals should carefully word their instructions to induce an external focus of attention whenever possible.

  12. EDITORIAL: Focus on Heart and Mind

    NASA Astrophysics Data System (ADS)

    Bodenschatz, Eberhard; Wolf, Fred

    2008-01-01

    tractable to support a comprehensive analysis of functional performance at the systems level. Analogously, experimental work increasingly probes the system dynamics simultaneously at multiple levels from cell to whole organ. Here an invaluable contribution of physics to the experimental characterization of large scale activity in cardiac and neuronal tissues is the currently emerging high level of quantitative precision and control. Long-term high precision recording of large scale activity patterns of neural and cardiac tissues increasingly supports the formulation of quantitative phenomenological theories of complex dynamical states as well the realization of algorithms for manipulating and controlling them. Both quantitative phenomenology and control are not only essential for bridging theory and experiment in complex systems; they are also indispensable for turning scientific insight into diagnostic progress and improved treatment for the affected heart and mind. The present Focus Issue in New Journal of Physics reflects well the richness and excitement of this currently rapidly evolving field. It combines theoretical and experimental approaches and covers analyses ranging from the organ level over investigations of model systems to the biophysics of individual cells. The articles below represent the first contributions to this collection and further additions will appear in the near future. Focus on Heart and Mind Contents 'Heart' contributions Spiral wave drift and complex-oscillatory spiral waves caused by heterogeneities in two-dimensional in vitro cardiac tissues Sung-Jae Woo, Jin Hee Hong, Tae Yun Kim, Byung Wook Bae and Kyoung J Lee Epicardial wavefronts arise from widely distributed transient sources during ventricular fibrillation in the isolated swine heart J M Rogers, G P Walcott, J D Gladden, S B Melnick, R E Ideker and M W Kay Efficient control of spiral wave location in an excitable medium with localized heterogeneities J Schlesner, V S Zykov, H Brandtst

  13. International Focus: Highlighting APPA Members Worldwide

    ERIC Educational Resources Information Center

    Glazner, Steve, Comp.

    2011-01-01

    While most APPA member institutions are located in the United States and Canada, there are also 45 of member institutions located internationally--from Australia and New Zealand to Southeast Asia to the Middle East to Europe. This article focuses on four of its international members: (1) American University of Kuwait (AUK); (2) American University…

  14. Focusing the Gaze: Teacher Interrogation of Practice

    ERIC Educational Resources Information Center

    Nayler, Jennifer M.; Keddie, Amanda

    2007-01-01

    Within an Australian context of diminishing opportunities for equitable educational outcomes, this paper calls for teacher engagement in a "politics of resistance" through their focused gaze in relation to the ways in which they are positioned in their everyday practice. Our belief is that the resultant knowledge might equip teachers to see more…

  15. Teaching Introductory Physics with an Environmental Focus

    ERIC Educational Resources Information Center

    Martinuk, Mathew; Moll, Rachel F.; Kotlicki, Andrzej

    2010-01-01

    Throughout North America the curriculum of introductory physics courses is nearly standardized. In 1992, Tobias wrote that four texts dominate 90% of the introductory physics market and current physics education research is focusing on how to sustain educational reforms. The instructional team at the University of British Columbia (UBC) recently…

  16. Superintendent Leadership: Focusing on District Culture

    ERIC Educational Resources Information Center

    Donnelly, Tanya A.; Adams, Jeffery S.; Smith, Dwayne E.

    2012-01-01

    This report describes a problem-based learning project focusing on superintendent leadership and stakeholder influence of school district culture. Current research findings suggest the importance of superintendent leadership in assessing, influencing, and enhancing school district culture. Multiple scholars wrote literature in the area of…

  17. "Stepping Up": A Focus on Facilitator Development

    ERIC Educational Resources Information Center

    Kostouros, Patricia; Warthe, D. Gaye; Carter-Snell, Catherine; Burnett, Che

    2016-01-01

    This article examines the impact on peer facilitators in "Stepping Up," a dating violence prevention program at a Canadian university. A focus group held eight months following the delivery of the program determined the personal impact of involvement in the program. Results indicate that peer facilitators experienced personal growth as…

  18. Improving Teacher Effectiveness through Focused Graduate Education

    ERIC Educational Resources Information Center

    Lease, Anthony; Garrison, Lawrence F.

    2008-01-01

    This article focuses on a unique and cutting-edge master's degree program in an urban setting that is designed to increase teacher effectiveness and that has positively affected student academic achievement. The major premise of the article is that traditional master's degree programs, as represented by a series of independent courses taught by…

  19. Focused ion beam micromilling and articles therefrom

    DOEpatents

    Lamartine, Bruce C.; Stutz, Roger A.

    1998-01-01

    An ultrahigh vacuum focused ion beam micromilling apparatus and process are isclosed. Additionally, a durable data storage medium using the micromilling process is disclosed, the durable data storage medium capable of storing, e.g., digital or alphanumeric characters as well as graphical shapes or characters.

  20. Latinos and the Media. Focus "En Foco".

    ERIC Educational Resources Information Center

    Vasquez, Blanca, Ed.

    1990-01-01

    This issue focuses on Latin Americans and the media, with emphasis on portrayal of the Latin American in United States mass media. "Puerto Ricans and the Media: A Personal Statement" (B. Vasquez) recalls the author's experiences as a young girl in the New York City public schools and in an urban college. The critical importance of the media in…