Subject-specific bone attenuation correction for brain PET/MR: can ZTE-MRI substitute CT scan accurately?

NASA Astrophysics Data System (ADS)

Khalifé, Maya; Fernandez, Brice; Jaubert, Olivier; Soussan, Michael; Brulon, Vincent; Buvat, Irène; Comtat, Claude

2017-10-01

In brain PET/MR applications, accurate attenuation maps are required for accurate PET image quantification. An implemented attenuation correction (AC) method for brain imaging is the single-atlas approach that estimates an AC map from an averaged CT template. As an alternative, we propose to use a zero echo time (ZTE) pulse sequence to segment bone, air and soft tissue. A linear relationship between histogram normalized ZTE intensity and measured CT density in Hounsfield units (HU ) in bone has been established thanks to a CT-MR database of 16 patients. Continuous AC maps were computed based on the segmented ZTE by setting a fixed linear attenuation coefficient (LAC) to air and soft tissue and by using the linear relationship to generate continuous μ values for the bone. Additionally, for the purpose of comparison, four other AC maps were generated: a ZTE derived AC map with a fixed LAC for the bone, an AC map based on the single-atlas approach as provided by the PET/MR manufacturer, a soft-tissue only AC map and, finally, the CT derived attenuation map used as the gold standard (CTAC). All these AC maps were used with different levels of smoothing for PET image reconstruction with and without time-of-flight (TOF). The subject-specific AC map generated by combining ZTE-based segmentation and linear scaling of the normalized ZTE signal into HU was found to be a good substitute for the measured CTAC map in brain PET/MR when used with a Gaussian smoothing kernel of 4~mm corresponding to the PET scanner intrinsic resolution. As expected TOF reduces AC error regardless of the AC method. The continuous ZTE-AC performed better than the other alternative MR derived AC methods, reducing the quantification error between the MRAC corrected PET image and the reference CTAC corrected PET image.

Non-linear transfer characteristics of stimulation and recording hardware account for spurious low-frequency artifacts during amplitude modulated transcranial alternating current stimulation (AM-tACS).

PubMed

Kasten, Florian H; Negahbani, Ehsan; Fröhlich, Flavio; Herrmann, Christoph S

2018-05-31

Amplitude modulated transcranial alternating current stimulation (AM-tACS) has been recently proposed as a possible solution to overcome the pronounced stimulation artifact encountered when recording brain activity during tACS. In theory, AM-tACS does not entail power at its modulating frequency, thus avoiding the problem of spectral overlap between brain signal of interest and stimulation artifact. However, the current study demonstrates how weak non-linear transfer characteristics inherent to stimulation and recording hardware can reintroduce spurious artifacts at the modulation frequency. The input-output transfer functions (TFs) of different stimulation setups were measured. Setups included recordings of signal-generator and stimulator outputs and M/EEG phantom measurements. 6 th -degree polynomial regression models were fitted to model the input-output TFs of each setup. The resulting TF models were applied to digitally generated AM-tACS signals to predict the frequency of spurious artifacts in the spectrum. All four setups measured for the study exhibited low-frequency artifacts at the modulation frequency and its harmonics when recording AM-tACS. Fitted TF models showed non-linear contributions significantly different from zero (all p < .05) and successfully predicted the frequency of artifacts observed in AM-signal recordings. Results suggest that even weak non-linearities of stimulation and recording hardware can lead to spurious artifacts at the modulation frequency and its harmonics. These artifacts were substantially larger than alpha-oscillations of a human subject in the MEG. Findings emphasize the need for more linear stimulation devices for AM-tACS and careful analysis procedures, taking into account low-frequency artifacts to avoid confusion with effects of AM-tACS on the brain. Copyright © 2018 Elsevier Inc. All rights reserved.

Sorption and Transport of Pharmaceutical chemicals in Organic- and Mineral-rich Soils

NASA Astrophysics Data System (ADS)

Vulava, V. M.; Schwindaman, J.; Murphey, V.; Kuzma, S.; Cory, W.

2011-12-01

Pharmaceutical, active ingredients in personal care products (PhACs), and their derivative compounds are increasingly ubiquitous in surface waters across the world. Sorption and transport of four relatively common PhACs (naproxen, ibuprofen, cetirizine, and triclosan) in different natural soils was measured. All of these compounds are relatively hydrophobic (log KOW>2) and have acid/base functional groups, including one compound that is zwitterionic (cetirizine.) The main goal of this study was to correlate organic matter (OM) and clay content in natural soils and sediment with sorption and degradation of PhACs and ultimately their potential for transport within the subsurface environment. A- and B-horizon soils were collected from four sub-regions within a pristine managed forested watershed near Charleston, SC, with no apparent sources of anthropogenic contamination. These four soil series had varying OM content (fOC) between 0.4-9%, clay mineral content between 6-20%, and soil pH between 4.5-6. The A-horizon soils had higher fOC and lower clay content than the B-horizon soils. Sorption isotherms measured from batch sorption experimental data indicated a non-linear sorption relationship in all A- and B-horizon soils - stronger sorption was observed at lower PhAC concentrations and lower sorption at higher concentrations. Three PhACs (naproxen, ibuprofen, and triclosan) sorbed more strongly with higher fOC A-horizon soils compared with the B-horizon soils. These results show that soil OM had a significant role in strongly binding these three PhACs, which had the highest KOW values. In contrast, cetirizine, which is predominantly positively charged at pH below 8, strongly sorbed to soils with higher clay mineral content and least strongly to higher fOC soils. All sorption isotherms fitted well to the Freundlich model. For naproxen, ibuprofen, and triclosan, there was a strong and positive linear correlation between the Freundlich adsorption constant, Kf, and fOC, again indicating that these PhACs preferentially partition into the soil OM. Such a correlation was absent for cetirizine. Breakthrough curves of PhACs measured in homogeneous packed soil columns indicated that PhAC transport was affected by chemical nonequilibrium processes depending on the soil and PhAC chemistry. The shape of the breakthrough curves indicated that there were two distinct sorption sites - OM and clay minerals - which influence nonequilibrium transport of these compounds. The retardation factor estimated using the distribution coefficient, Kd, measured from the sorption experiments was very similar to the measured value. While the sorption and transport data do not provide mechanistic information regarding the nature of PhAC interaction with chemical reactive components within geological materials, they do provide important information regarding potential fate of such compounds in the environment. The results also show the role that soil OM and mineral surfaces play in sequestering or transporting these chemicals. These insights have implications to the quality of the water resources in our communities.

Conformal Stereotactic Radiosurgery With Multileaf Collimation.

DTIC Science & Technology

1992-01-01

Hartmann, W. Schlegel, V. Sturm, B. Kober, 0. Pastyr, W.J. Lorenz, "Cerebral radiation surgery using moving field irradiation at a linear ac ...Kober, 0. Pastyr, W.J. Lorenz, "Cerebral radiation surgery using moving field irradiation at a linear ac - celerator facility," Int. J. Radiation...scattered photons), off-axis ratios (for points off of the central axis of the incident beam), percent depth dose or tissue maximum ratio (to ac - count for

Free piston variable-stroke linear-alternator generator

DOEpatents

Haaland, Carsten M.

1998-01-01

A free-piston variable stroke linear-alternator AC power generator for a combustion engine. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod.

An extended sequence specificity for UV-induced DNA damage.

PubMed

Chung, Long H; Murray, Vincent

2018-01-01

The sequence specificity of UV-induced DNA damage was determined with a higher precision and accuracy than previously reported. UV light induces two major damage adducts: cyclobutane pyrimidine dimers (CPDs) and pyrimidine(6-4)pyrimidone photoproducts (6-4PPs). Employing capillary electrophoresis with laser-induced fluorescence and taking advantages of the distinct properties of the CPDs and 6-4PPs, we studied the sequence specificity of UV-induced DNA damage in a purified DNA sequence using two approaches: end-labelling and a polymerase stop/linear amplification assay. A mitochondrial DNA sequence that contained a random nucleotide composition was employed as the target DNA sequence. With previous methodology, the UV sequence specificity was determined at a dinucleotide or trinucleotide level; however, in this paper, we have extended the UV sequence specificity to a hexanucleotide level. With the end-labelling technique (for 6-4PPs), the consensus sequence was found to be 5'-GCTC*AC (where C* is the breakage site); while with the linear amplification procedure, it was 5'-TCTT*AC. With end-labelling, the dinucleotide frequency of occurrence was highest for 5'-TC*, 5'-TT* and 5'-CC*; whereas it was 5'-TT* for linear amplification. The influence of neighbouring nucleotides on the degree of UV-induced DNA damage was also examined. The core sequences consisted of pyrimidine nucleotides 5'-CTC* and 5'-CTT* while an A at position "1" and C at position "2" enhanced UV-induced DNA damage. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Absolute Position Sensing Based on a Robust Differential Capacitive Sensor with a Grounded Shield Window

PubMed Central

Bai, Yang; Lu, Yunfeng; Hu, Pengcheng; Wang, Gang; Xu, Jinxin; Zeng, Tao; Li, Zhengkun; Zhang, Zhonghua; Tan, Jiubin

2016-01-01

A simple differential capacitive sensor is provided in this paper to measure the absolute positions of length measuring systems. By utilizing a shield window inside the differential capacitor, the measurement range and linearity range of the sensor can reach several millimeters. What is more interesting is that this differential capacitive sensor is only sensitive to one translational degree of freedom (DOF) movement, and immune to the vibration along the other two translational DOFs. In the experiment, we used a novel circuit based on an AC capacitance bridge to directly measure the differential capacitance value. The experimental result shows that this differential capacitive sensor has a sensitivity of 2 × 10−4 pF/μm with 0.08 μm resolution. The measurement range of this differential capacitive sensor is 6 mm, and the linearity error are less than 0.01% over the whole absolute position measurement range. PMID:27187393

Free piston variable-stroke linear-alternator generator

DOEpatents

Haaland, C.M.

1998-12-15

A free-piston variable stroke linear-alternator AC power generator for a combustion engine is described. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod. 8 figs.

Bioavailabilty of beta-amino acid and C-terminally derived PK/PBAN analogs

USDA-ARS?s Scientific Manuscript database

The ability of linear beta amino-acid-substituted peptides (PK-betaA-1: Ac-YFT[beta3-P]RLa; PK-betaA-2: Ac-Y[beta2-homoF]TPRLa; PK-betaA-3: Ac-Y[beta3-F]TPRLa and PK-betaA-4: Ac-[beta3-F]FT[beta3-P]RLa) and unsubstituted analogs (Ac-YFTPRLa and YFTPRLa) of the pyrokinin(PK)/pheromone biosynthesis-ac...

Kinetics of intercalation of lithium into NbSe3 and TiS2 cathodes

NASA Technical Reports Server (NTRS)

Ratnakumar, B. V.; Nagasubramanian, G.; Di Stefano, S.; Bankston, C. P.

1992-01-01

Titanium disulfide and niobium triselenide are two well-studied candidate materials for positive electrodes in rechargeable lithium cells. A comparative study of the kinetics of intercalation of lithium in both the cathodes is made here based on various electrochemical techniques, i.e., linear polarization, potentiodynamic polarization, and ac impedance under different experimental conditions such as prismatic or disk configuration of fresh, partially discharged, or cycled electrode. Further, the diffusion coefficients of lithium ions in these cathodes are estimated under these conditions using conventional techniques, i.e., ac impedance, chronocoulometry, chronoamperometry, and current pulse relaxation. Based on the values of the diffusion coefficients, the applicability of these methods for the determination of diffusion coefficients is discussed.

Theoretical and experimental analysis of amplitude control ablation and bipolar ablation in creating linear lesion and discrete lesions for treating atrial fibrillation.

PubMed

Yan, Shengjie; Wu, Xiaomei; Wang, Weiqi

2017-09-01

Radiofrequency (RF) energy is often used to create a linear lesion or discrete lesions for blocking the accessory conduction pathways for treating atrial fibrillation. By using finite element analysis, we study the ablation effect of amplitude control ablation mode (AcM) and bipolar ablation mode (BiM) in creating a linear lesion and discrete lesions in a 5-mm-thick atrial wall; particularly, the characteristic of lesion shape has been investigated in amplitude control ablation. Computer models of multipolar catheter were developed to study the lesion dimensions in atrial walls created through AcM, BiM and special electrodes activated ablation methods in AcM and BiM. To validate the theoretical results in this study, an in vitro experiment with porcine cardiac tissue was performed. At 40 V/20 V root mean squared (RMS) of the RF voltage for AcM, the continuous and transmural lesion was created by AcM-15s, AcM-5s and AcM-ad-20V ablation in 5-mm-thick atrial wall. At 20 V RMS for BiM, the continuous but not transmural lesion was created. AcM ablation yielded asymmetrical and discrete lesions shape, whereas the lesion shape turned to more symmetrical and continuous as the electrodes alternative activated period decreased from 15 s to 5 s. Two discrete lesions were created when using AcM, AcM-ad-40V, BiM-ad-20V and BiM-ad-40V. The experimental and computational thermal lesion shapes created in cardiac tissue were in agreement. Amplitude control ablation technology and bipolar ablation technology are feasible methods to create continuous lesion or discrete for pulmonary veins isolation.

Modeling Laterality of the Globus Pallidus Internus in Patients With Parkinson's Disease.

PubMed

Sharim, Justin; Yazdi, Daniel; Baohan, Amy; Behnke, Eric; Pouratian, Nader

2017-04-01

Neurosurgical interventions such as deep brain stimulation surgery of the globus pallidus internus (GPi) play an important role in the treatment of medically refractory Parkinson's disease (PD), and require high targeting accuracy. Variability in the laterality of the GPi across patients with PD has not been well characterized. The aim of this report is to identify factors that may contribute to differences in position of the motor region of GPi. The charts and operative reports of 101 PD patients following deep brain stimulation surgery (70 males, aged 11-78 years) representing 201 GPi were retrospectively reviewed. Data extracted for each subject include age, gender, anterior and posterior commissures (AC-PC) distance, and third ventricular width. Multiple linear regression, stepwise regression, and relative importance of regressors analysis were performed to assess the predictive ability of these variables on GPi laterality. Multiple linear regression for target vs. third ventricular width, gender, AC-PC distance, and age were significant for normalized linear regression coefficients of 0.333 (p < 0.0001), 0.206 (p = 0.00219), 0.168 (p = 0.0119), and 0.159 (p = 0.0136), respectively. Third ventricular width, gender, AC-PC distance, and age each account for 44.06% (21.38-65.69%, 95% CI), 20.82% (10.51-35.88%), 21.46% (8.28-37.05%), and 13.66% (2.62-28.64%) of the R 2 value, respectively. Effect size calculation was significant for a change in the GPi laterality of 0.19 mm per mm of ventricular width, 0.11 mm per mm of AC-PC distance, 0.017 mm per year in age, and 0.54 mm increase for male gender. This variability highlights the limitations of indirect targeting alone, and argues for the continued use of MRI as well as intraoperative physiological testing to account for such factors that contribute to patient-specific variability in GPi localization. © 2016 International Neuromodulation Society.

AC Application of HTS Conductors in Highly Dynamic Electric Motors

NASA Astrophysics Data System (ADS)

Oswald, B.; Best, K.-J.; Setzer, M.; Duffner, E.; Soell, M.; Gawalek, W.; Kovalev, L. K.

2006-06-01

Based on recent investigations we design highly dynamic electric motors up to 400 kW and linear motors up to 120 kN linear force using HTS bulk material and HTS tapes. The introduction of HTS tapes into AC applications in electric motors needs fundamental studies on double pancake coils under transversal magnetic fields. First theoretical and experimental results on AC field distributions in double-pancake-coils and corresponding AC losses will be presented. Based on these results the simulation of the motor performance confirms extremely high power density and efficiency of both types of electric motors. Improved characteristics of rare earth permanent magnets used in our motors at low temperatures give an additional technological benefit.

Efficacy of Transcerebellar Diameter/Abdominal Circumference Versus Head Circumference/Abdominal Circumference in Predicting Asymmetric Intrauterine Growth Retardation

PubMed Central

Bhimarao; Bhat, Venkataramana; Gowda, Puttanna VN

2015-01-01

Background The high incidence of IUGR and its low recognition lead to increasing perinatal morbidity and mortality for which prediction of IUGR with timely management decisions is of paramount importance. Many studies have compared the efficacy of several gestational age independent parameters and found that TCD/AC is a better predictor of asymmetric IUGR. Aim To compare the accuracy of transcerebellar diameter/abdominal circumference with head circumference/abdominal circumference in predicting asymmetric intrauterine growth retardation after 20 weeks of gestation. Materials and Methods The prospective study was conducted over a period of one year on 50 clinically suspected IUGR pregnancies who were evaluated with 3.5 MHz frequency ultrasound scanner by a single sonologist. BPD, HC, AC and FL along with TCD were measured for assessing the sonological gestational age. Two morphometric ratios- TCD/AC and HC/AC were calculated. Estimated fetal weight was calculated for all these pregnancies and its percentile was determined. Statistical Methods The TCD/AC and HC/AC ratios were correlated with advancing gestational age to know if these were related to GA. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy (DA) for TCD/AC and HC/AC ratios in evaluating IUGR fetuses were calculated. Results In the present study, linear relation of TCD and HC in IUGR fetuses with gestation was noted. The sensitivity, specificity, PPV, NPV & DA were 88%, 93.5%, 77.1%, 96.3% & 92.4% respectively for TCD/AC ratio versus 84%, 92%, 72.4%, 95.8% & 90.4% respectively for HC/AC ratio in predicting IUGR. Conclusion Both ratios were gestational age independent and can be used in detecting IUGR with good diagnostic accuracy. However, TCD/AC ratio had a better diagnostic validity and accuracy compared to HC/AC ratio in predicting asymmetric IUGR. PMID:26557588

Bowel obstruction rates in antecolic/antegastric versus retrocolic/retrogastric Roux limb gastric bypass: a meta-analysis.

PubMed

Al Harakeh, Ayman B; Kallies, Kara J; Borgert, Andrew J; Kothari, Shanu N

2016-01-01

Previous literature is varied with regard to rates of bowel obstruction after laparoscopic Roux-en-Y gastric bypass (LRYGB). Internal herniation through mesenteric defects is a common cause of bowel obstructions. There are advantages and disadvantages to routing the Roux limb via a retrocolic/retrogastric (RC/RG) versus an antecolic/antegastric (AC/AG) position. To review the literature comparing obstruction rates in RYGB using the antecolic versus retrocolic approach. Community-based integrated multispecialty health system with a teaching hospital serving 19 counties over a 3-state region. A literature search for articles published from 1994-2013 was completed. Articles were included if they reported an n>25, Roux limb route, obstruction rate by route, and follow-up duration. Statistical analysis included χ(2) test by patient number. The initial search identified 241 articles; 8 met inclusion criteria. There were 4805 patients in the AC/AG group, and 2238 in the RC/RG group. Follow-up ranged from 0 to 68 months. A linear stapled technique was reported in 4231 (88%) patients in the AC/AG group and 1541 (69%) of RC/RG group. Handsewn closure of mesenteric defects was reported in 2152 (45%) patients in the AC/AG group and 1012 (45%) patients in the RC/RG group. Bowel obstructions occurred in 68 (1.4%) patients in the AC/AG group and 117 (5.2%) patients in the RC/RG group (P<.001). Internal hernias were reported in 65 (1.3%) patients in the AC/AG group and 52 (2.3%) patients in the RC/RG group (P<.001). Two mortalities were reported in the AC/AG group. Increased rates of bowel obstruction and internal hernia were observed in the RC/RG group compared with the AC/AG group. A prospective, randomized trial would be necessary to definitively determine the impact of Roux limb position and routine closure of mesenteric defects on bowel obstruction rates after gastric bypass. Copyright © 2016 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

General purpose computer programs for numerically analyzing linear ac electrical and electronic circuits for steady-state conditions

NASA Technical Reports Server (NTRS)

Egebrecht, R. A.; Thorbjornsen, A. R.

1967-01-01

Digital computer programs determine steady-state performance characteristics of active and passive linear circuits. The ac analysis program solves the basic circuit parameters. The compiler program solves these circuit parameters and in addition provides a more versatile program by allowing the user to perform mathematical and logical operations.

Probabilistic dual heuristic programming-based adaptive critic

NASA Astrophysics Data System (ADS)

Herzallah, Randa

2010-02-01

Adaptive critic (AC) methods have common roots as generalisations of dynamic programming for neural reinforcement learning approaches. Since they approximate the dynamic programming solutions, they are potentially suitable for learning in noisy, non-linear and non-stationary environments. In this study, a novel probabilistic dual heuristic programming (DHP)-based AC controller is proposed. Distinct to current approaches, the proposed probabilistic (DHP) AC method takes uncertainties of forward model and inverse controller into consideration. Therefore, it is suitable for deterministic and stochastic control problems characterised by functional uncertainty. Theoretical development of the proposed method is validated by analytically evaluating the correct value of the cost function which satisfies the Bellman equation in a linear quadratic control problem. The target value of the probabilistic critic network is then calculated and shown to be equal to the analytically derived correct value. Full derivation of the Riccati solution for this non-standard stochastic linear quadratic control problem is also provided. Moreover, the performance of the proposed probabilistic controller is demonstrated on linear and non-linear control examples.

Towards Implementing an MR-based PET Attenuation Correction Method for Neurological Studies on the MR-PET Brain Prototype

PubMed Central

Catana, Ciprian; van der Kouwe, Andre; Benner, Thomas; Michel, Christian J.; Hamm, Michael; Fenchel, Matthias; Fischl, Bruce; Rosen, Bruce; Schmand, Matthias; Sorensen, A. Gregory

2013-01-01

A number of factors have to be considered for implementing an accurate attenuation correction (AC) in a combined MR-PET scanner. In this work, some of these challenges were investigated and an AC method based entirely on the MR data obtained with a single dedicated sequence was developed and used for neurological studies performed with the MR-PET human brain scanner prototype. Methods The focus was on the bone/air segmentation problem, the bone linear attenuation coefficient selection and the RF coil positioning. The impact of these factors on the PET data quantification was studied in simulations and experimental measurements performed on the combined MR-PET scanner. A novel dual-echo ultra-short echo time (DUTE) MR sequence was proposed for head imaging. Simultaneous MR-PET data were acquired and the PET images reconstructed using the proposed MR-DUTE-based AC method were compared with the PET images reconstructed using a CT-based AC. Results Our data suggest that incorrectly accounting for the bone tissue attenuation can lead to large underestimations (>20%) of the radiotracer concentration in the cortex. Assigning a linear attenuation coefficient of 0.143 or 0.151 cm−1 to bone tissue appears to give the best trade-off between bias and variability in the resulting images. Not identifying the internal air cavities introduces large overestimations (>20%) in adjacent structures. Based on these results, the segmented CT AC method was established as the “silver standard” for the segmented MR-based AC method. Particular to an integrated MR-PET scanner, ignoring the RF coil attenuation can cause large underestimations (i.e. up to 50%) in the reconstructed images. Furthermore, the coil location in the PET field of view has to be accurately known. Good quality bone/air segmentation can be performed using the DUTE data. The PET images obtained using the MR-DUTE- and CT-based AC methods compare favorably in most of the brain structures. Conclusion An MR-DUTE-based AC method was implemented considering all these factors and our preliminary results suggest that this method could potentially be as accurate as the segmented CT method and it could be used for quantitative neurological MR-PET studies. PMID:20810759

Toward implementing an MRI-based PET attenuation-correction method for neurologic studies on the MR-PET brain prototype.

PubMed

Catana, Ciprian; van der Kouwe, Andre; Benner, Thomas; Michel, Christian J; Hamm, Michael; Fenchel, Matthias; Fischl, Bruce; Rosen, Bruce; Schmand, Matthias; Sorensen, A Gregory

2010-09-01

Several factors have to be considered for implementing an accurate attenuation-correction (AC) method in a combined MR-PET scanner. In this work, some of these challenges were investigated, and an AC method based entirely on the MRI data obtained with a single dedicated sequence was developed and used for neurologic studies performed with the MR-PET human brain scanner prototype. The focus was on the problem of bone-air segmentation, selection of the linear attenuation coefficient for bone, and positioning of the radiofrequency coil. The impact of these factors on PET data quantification was studied in simulations and experimental measurements performed on the combined MR-PET scanner. A novel dual-echo ultrashort echo time (DUTE) MRI sequence was proposed for head imaging. Simultaneous MR-PET data were acquired, and the PET images reconstructed using the proposed DUTE MRI-based AC method were compared with the PET images that had been reconstructed using a CT-based AC method. Our data suggest that incorrectly accounting for the bone tissue attenuation can lead to large underestimations (>20%) of the radiotracer concentration in the cortex. Assigning a linear attenuation coefficient of 0.143 or 0.151 cm(-1) to bone tissue appears to give the best trade-off between bias and variability in the resulting images. Not identifying the internal air cavities introduces large overestimations (>20%) in adjacent structures. On the basis of these results, the segmented CT AC method was established as the silver standard for the segmented MRI-based AC method. For an integrated MR-PET scanner, in particular, ignoring the radiofrequency coil attenuation can cause large underestimations (i.e.,

An AC electroosmotic micropump for circular chromatographic applications.

PubMed

Debesset, S; Hayden, C J; Dalton, C; Eijkel, J C T; Manz, A

2004-08-01

Flow rates of up to 50 microm s(-1) have been successfully achieved in a closed-loop channel using an AC electroosmotic pump. The AC electroosmotic pump is made of an interdigitated array of unequal width electrodes located at the bottom of a channel, with an AC voltage applied between the small and the large electrodes. The flow rate was found to increase linearly with the applied voltage and to decrease linearly with the applied frequency. The pump is expected to be suitable for circular chromatography for the following reasons: the driving forces are distributed over the channel length and the pumping direction is set by the direction of the interdigitated electrodes. Pumping in a closed-loop channel can be achieved by arranging the electrode pattern in a circle. In addition the inherent working principle of AC electroosmotic pumping enables the independent optimisation of the channel height or the flow velocity.

Hispanic residential ethnic density and depression in post-ACS patients: Re-thinking the role of social support

PubMed Central

Denton, Ellen-ge D.; Shaffer, Jonathan A.; Alcantara, Carmela; Clemow, Lynn; Brondolo, Elizabeth

2014-01-01

Objective The ethnic density hypothesis suggests that ethnic density confers greater social support and consequently protects against depressive symptoms in ethnic minority individuals. However, the potential benefits of ethnic density have not been examined in individuals who are facing a specific and salient life stressor. We examined the degree to which the effects of Hispanic ethnic density on depressive symptoms are explained by socioeconomic resources and social support. Methods Patients with acute coronary syndrome (ACS, N = 472) completed the Beck Depression Inventory (BDI) and measures of demographics, ACS clinical factors and disease severity, and perceived social support. Neighborhood characteristics, including median income, number of single-parent households, and Hispanic ethnic density, were extracted from the American Community Survey Census (2005 – 2009) for each patient using his/her geocoded address. Results In a linear regression analysis adjusted for demographic and clinical factors, Hispanic ethnic density was positively associated with depressive symptoms (β = .09, SE = .04, p = .03). However, Hispanic density was no longer a significant predictor of depressive symptoms when measures of neighborhood socioeconomic disadvantage were controlled. In addition, the effects of Hispanic density were not the same for all groups. The relationship of Hispanic density on depressive symptoms was moderated by nativity status. Among US-born patients with ACS, there was a significant positive relationship between Hispanic density and depressive symptoms, and social support significantly mediated this effect. There was no observed effect of Hispanic density to depressive symptoms for foreign-born ACS patients. Discussion Although previous research suggests that ethnic density may be protective against depression, our data suggest that among patients with ACS, living in a community with a high concentration of Hispanic individuals is associated with constrained social and economic resources which are themselves associated with greater depressive symptoms. These data add to a growing body of literature on the effects of racial or ethnic segregation on health outcomes. PMID:24985313

Linear optics measurements and corrections using an AC dipole in RHIC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, G.; Bai, M.; Yang, L.

2010-05-23

We report recent experimental results on linear optics measurements and corrections using ac dipole. In RHIC 2009 run, the concept of the SVD correction algorithm is tested at injection energy for both identifying the artificial gradient errors and correcting it using the trim quadrupoles. The measured phase beatings were reduced by 30% and 40% respectively for two dedicated experiments. In RHIC 2010 run, ac dipole is used to measure {beta}* and chromatic {beta} function. For the 0.65m {beta}* lattice, we observed a factor of 3 discrepancy between model and measured chromatic {beta} function in the yellow ring.

A linearly controlled direct-current power source for high-current inductive loads in a magnetic suspension wind tunnel

NASA Technical Reports Server (NTRS)

Tripp, John S.; Daniels, Taumi S.

1990-01-01

The NASA Langley 6 inch magnetic suspension and balance system (MSBS) requires an independently controlled bidirectional DC power source for each of six positioning electromagnets. These electromagnets provide five-degree-of-freedom control over a suspended aerodynamic test model. Existing power equipment, which employs resistance coupled thyratron controlled rectifiers as well as AC to DC motor generator converters, is obsolete, inefficient, and unreliable. A replacement six phase bidirectional controlled bridge rectifier is proposed, which employs power MOSFET switches sequenced by hybrid analog/digital circuits. Full load efficiency is 80 percent compared to 25 percent for the resistance coupled thyratron system. Current feedback provides high control linearity, adjustable current limiting, and current overload protection. A quenching circuit suppresses inductive voltage impulses. It is shown that 20 kHz interference from positioning magnet power into MSBS electromagnetic model position sensors results predominantly from capacitively coupled electric fields. Hence, proper shielding and grounding techniques are necessary. Inductively coupled magnetic interference is negligible.

Predictability of the 2012 Great Arctic Cyclone on medium-range timescales

NASA Astrophysics Data System (ADS)

Yamagami, Akio; Matsueda, Mio; Tanaka, Hiroshi L.

2018-03-01

Arctic Cyclones (ACs) can have a significant impact on the Arctic region. Therefore, the accurate prediction of ACs is important in anticipating their associated environmental and societal costs. This study investigates the predictability of the 2012 Great Arctic Cyclone (AC12) that exhibited a minimum central pressure of 964 hPa on 6 August 2012, using five medium-range ensemble forecasts. We show that the development and position of AC12 were better predicted in forecasts initialized on and after 4 August 2012. In addition, the position of AC12 was more predictable than its development. A comparison of ensemble members, classified by the error in predictability of the development and position of AC12, revealed that an accurate prediction of upper-level fields, particularly temperature, was important for the prediction of this event. The predicted position of AC12 was influenced mainly by the prediction of the polar vortex, whereas the predicted development of AC12 was dependent primarily on the prediction of the merging of upper-level warm cores. Consequently, an accurate prediction of the polar vortex position and the development of the warm core through merging resulted in better prediction of AC12.

Sensitivity of amplitude-phase characteristics of the surface air temperature annual cycle to variations in annual mean temperature

NASA Astrophysics Data System (ADS)

Eliseev, A. V.; Mokhov, I. I.; Guseva, M. S.

2006-05-01

The ERA40 and NCEP/NCAR data over 1958 1998 were used to estimate the sensitivity of amplitude-phase characteristics (APCs) of the annual cycle (AC) of the surface air temperature (SAT) T s. The results were compared with outputs of the ECHAM4/OPYC3, HadCM3, and INM RAS general circulation models and the IAP RAS climate model of intermediate complexity, which were run with variations in greenhouse gases and sulfate aerosol specified over 1860 2100. The analysis was performed in terms of the linear regression coefficients b of SAT AC APCs on the local annual mean temperature and in terms of the sensitivity characteristic D = br 2, which takes into account not only the linear regression coefficient but also its statistical significance (via the correlation coefficient r). The reanalysis data were used to reveal the features of the tendencies of change in the SAT AC APCs in various regions, including areas near the snow-ice boundary, storm-track ocean regions, large desert areas, and the tropical Pacific. These results agree with earlier observations. The model computations are in fairly good agreement with the reanalysis data in regions of statistically significant variations in SAT AC APCs. The differences between individual models and the reanalysis data can be explained, in particular, in terms of the features of the sea-ice schemes used in the models. Over the land in the middle and high latitudes of the Northern Hemisphere, the absolute values of D for the fall phase time and the interval of exceeding exhibit a positive intermodel correlation with the absolute value of D for the annual-harmonic amplitude. Over the ocean, the models reproducing larger (in modulus) sensitivity parameters of the SAT annual-harmonic amplitude are generally characterized by larger (in modulus) negative sensitivity values of the semiannual-harmonic amplitude T s, 2, especially at latitudes characteristic of the sea-ice boundary. In contrast to the averaged fields of AC APCs and their interannual standard deviations, the sensitivity parameters of the SAT AC APCs on a regional scale vary noticeably for various types of anthropogenic forcing.

Activated carbon oxygen content influence on water and surfactant adsorption.

PubMed

Pendleton, Phillip; Wu, Sophie Hua; Badalyan, Alexander

2002-02-15

This research investigates the adsorption properties of three activated carbons (AC) derived from coconut, coal, and wood origin. Each carbon demonstrates different levels of resistance to 2 M NaOH treatment. The coconut AC offers the greatest and wood AC the least resistance. The influence of base treatment is mapped in terms of its effects on specific surface area, micropore volume, water adsorption, and dodecanoic acid adsorption from both water and 2 M NaOH solution. A linear relationship exists between the number of water molecules adsorbed at the B-point of the water adsorption isotherm and the oxygen content determined from elemental analysis. Surfactant adsorption isotherms from water and 2 M NaOH indicate that the AC oxygen content effects a greater dependence on affinity for surfactant than specific surface area and micropore volume. We show a linear relationship between the plateau amount of surfactant adsorbed and the AC oxygen content in both water and NaOH phases. The higher the AC oxygen content, the lower the amount of surfactant adsorbed. In contrast, no obvious relationship could be drawn between the surfactant amount adsorbed and the surface area.

Influence of bending stress on flux distribution in toroidal transducers

NASA Astrophysics Data System (ADS)

Goktepe, M.; Meydan, T.

1994-05-01

Amorphous transducers consisting of toroidally wound amorphous ribbon with a magnetising winding and search coil windings have been investigated. The application of displacement to the toroid gives a linear search coil voltage against the applied force characteristics. The position of the search coils with respect to the applied force has been studied and it is shown that the effect of applied force is localised. These results have elucidated the operation of ac amorphous ribbon transducers and enabled improved designs to be produced.

Correlation of symptom depression levels with mean platelet volume rate on patients of acute coronary syndrome

NASA Astrophysics Data System (ADS)

Hasugian, L.; Hanum, H.; Hanida, W.; Safri, Z.

2018-03-01

Patients with Depression and the acute coronary syndrome (ACS) is rarely detected, although in some studies say that depression can worsen cardiovascularly and increase mortality. From research, Canan F et al found that increasing levels of Mean platelet volume (MPV) as a risk factor for atherosclerosis and MPV was higher in patients with depression compared with patients without depression. In this study used observational methods of measurement of cross-sectional data. Research began in November 2015 - May 2016 against General Hospital inpatients H. Adam Malik Medan. There are 64 patients with a diagnosis of ACS were given quieter Beck Depression Inventory (BDI), then calculated a score of BDI patients and MPV levels were seen when they first entered the hospital before being given treatment. Patients answered quieter on days 3-7 after diagnosis ACS. ACS Patients were divided into 3 groups: acute myocardial infarction with ST elevation, acute myocardial infarction with non-ST elevation and unstable angina pectoris. The level of depression is grouped into not depression, mild depression, moderate depression and severe depression. Statistically significant with p-value<0.05Based on the linear correlation analysis, it was found a positive correlation with r=0.542. And the relationship is statistically significant with p-value 0.000003.

Non-linearity of the response accommodative convergence to accommodation ratio.

PubMed

Johnston, Miriam S; Firth, Alison Y

2013-09-01

Previous studies have reported variation in stimulus accommodative convergence to accommodation (AC/A) ratio across differing accommodative stimuli. Response AC/A ratio was assessed across 4 accommodative demands to determine if these differences could be due to accommodative inaccuracies to stimuli. Twenty-three student participants aged 18 to 26 years (mean age 20.3 ± 1.7 years) successfully completed all testing conditions. The modified Thorington technique was used at 4 m to measure heterophoria. The Shin Nippon SRW 5000 infrared autorefractor was used to determine accommodative change to -1.50, -3.00, -4.50, and -6.00D lens stimuli. Significant differences were found in response AC/A ratio between different minus lens stimulated accommodative demands (p < 0.001). Mean AC/A ratio values were 3.11 ± 1.29 with the -1.50D lens stimulus; 4.03 ± 2.11 with -3.00D; 4.14 ± 1.40 with -4.50D; and 4.48 ± 1.56 with -6.00D. No differences in linearity were noted between myopes and non-myopic participants, but myopes tended to have higher response AC/A ratios than non-myopes, mean 4.88 ± 1.89 for myopes vs 3.61 ± 1.47 for non-myopes (p = 0.045). Response AC/A ratio did not display linearity across 4 minus lens accommodative stimuli, but tended to increase with accommodative demand. Significant variability in response AC/A ratio was found, both within individuals to different accommodative demands, and between individuals across the data set.

Relationship between perception of malocclusion and the psychological impact of dental aesthetics in university students

PubMed Central

Montiel-Company, José-María; Pinho, Teresa; Almerich-Silla, José-Manuel

2015-01-01

Introduction and Objectives: The objectives were to assess the relationship between perceived smile aesthetics and perceived psychological impact as measured by the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ), and their own perception of it using the Aesthetic Component of the Index of Orthodontic Treatment Need (IOTN-AC) and a Visual Analog Scale (VAS); relate the IOTN-AC and VAS to the PIDAQ; and study the predictive capacity of the scales for psychological impact. Material and Methods: A cross-sectional study was conducted in 447 college students in Spain and Portugal (average age 20.4 years, 33.1% men and 66.9% women). The online self-completed surveys used the recently-validated Spanish and Portuguese versions of the PIDAQ to assess the self–reported psychological impact of the students’ dental aesthetics and IOTN-AC and an ad hoc 100 mm VAS for their perception of their dental aesthetics. Results: PIDAQ was linearly correlated with IOTN AC and VAS. Pearson’s coefficient was 0.55 for PIDAQ and IOTN-AC (CI 95% 0.48-0.61) and -0.72 for PIDAQ and VAS (CI 95% -0.66 - -0.76). VAS and IOTN-AC were predictive variables in a linear regression model of the total PIDAQ score. The VAS diagnosed individuals whose dental aesthetics had a self-perceived psychological impact (area under the curve 0.827, CI 95% 0.787-0.868) more precisely than the IOTN-AC (area under the curve 0.742, CI 95% 0. 696-0.788). Conclusions: In adults patients, there is a significant linear relationship between perceived smile aesthetics and self-perceived psychological impact. Key words:Visual Analog Scale, Index of Orthodontic Treatment Need, malocclusion, psychological, aesthetics. PMID:25810834

WFPC2 CYCLE 15 Intflat Linearity Check and Filter Rotation Anomaly Monitor

NASA Astrophysics Data System (ADS)

Gonzaga, Shireen

2006-07-01

Intflat observations will be taken to provide a linearity check: the linearity test consists of a series of intflats in F555W, in each gain and each shutter. A combination of intflats, visflats, and earthflats will be used to check the repeatability of filter wheel motions. {Intflat sequences tied to decons, visits 1-18 in prop 10363, have been moved to the cycle 15 decon proposal xxxx for easier scheduling.} Note: long-exposure WFPC2 intflats must be scheduled during ACS anneals to prevent stray light from the WFPC2 lamps from contaminating long ACS external exposures.

Diagnostics of the Fermilab Tevatron using an AC dipole

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyamoto, Ryoichi

2008-08-01

The Fermilab Tevatron is currently the world's highest energy colliding beam facility. Its counter-rotating proton and antiproton beams collide at 2 TeV center-of-mass. Delivery of such intense beam fluxes to experiments has required improved knowledge of the Tevatron's beam optical lattice. An oscillating dipole magnet, referred to as an AC dipole, is one of such a tool to non-destructively assess the optical properties of the synchrotron. We discusses development of an AC dipole system for the Tevatron, a fast-oscillating (f ~ 20 kHz) dipole magnet which can be adiabatically turned on and off to establish sustained coherent oscillations of themore » beam particles without affecting the transverse emittance. By utilizing an existing magnet and a higher power audio amplifier, the cost of the Tevatron AC dipole system became relatively inexpensive. We discuss corrections which must be applied to the driven oscillation measurements to obtain the proper interpretation of beam optical parameters from AC dipole studies. After successful operations of the Tevatron AC dipole system, AC dipole systems, similar to that in the Tevatron, will be build for the CERN LHC. We present several measurements of linear optical parameters (beta function and phase advance) for the Tevatron, as well as studies of non-linear perturbations from sextupole and octupole elements.« less

Comparative study of ROR2 and WNT5a expression in squamous/adenosquamous carcinoma and adenocarcinoma of the gallbladder

PubMed Central

Wu, Zheng-Chun; Xiong, Li; Wang, Ling-Xiang; Miao, Xiong-Ying; Liu, Zi-Ru; Li, Dai-Qiang; Zou, Qiong; Liu, Kui-Jie; Zhao, Hua; Yang, Zhu-Lin

2017-01-01

AIM To investigate the expression and clinical pathological significance of ROR2 and WNT5a in gallbladder squamous/adenosquamous carcinoma (SC/ASC) and adenocarcinoma (AC). METHODS EnVision immunohistochemistry was used to stain for ROR2 and WNT5a in 46 SC/ASC patients and 80 AC patients. RESULTS Poorly differentiated AC among AC patients aged > 45 years were significantly more frequent compared with SC/ASC patients, while tumors with a maximal diameter > 3 cm in the SC/ASC group were significantly more frequent compared with the AC group. Positive ROR2 and WNT5a expression was significantly lower in SC/ASC or AC with a maximal mass diameter ≤ 3 cm, a TNM stage of I + II, no lymph node metastasis, no surrounding invasion, and radical resection than in patients with a maximal mass diameter > 3 cm, TNM stage IV, lymph node metastasis, surrounding invasion, and no resection. Positive ROR2 expression in patients with highly differentiated SC/ASC was significantly lower than in patients with poorly differentiated SC/ASC. Positive ROR2 and WNT5a expression levels in highly differentiated AC were significantly lower than in poorly differentiated AC. Kaplan-Meier survival analysis showed that differentiation degree, maximal mass diameter, TNM stage, lymph node metastasis, surrounding invasion, surgical procedure and the ROR2 and WNT5a expression levels were closely related to average survival of SC/ASC or AC. The survival of SC/ASC or AC patients with positive expression of ROR2 and WNT5a was significantly shorter than that of patients with negative expression results. Cox multivariate analysis revealed that poor differentiation, a maximal diameter of the mass ≥ 3 cm, TNM stage III or IV, lymph node metastasis, surrounding invasion, unresected surgery and positive ROR2 or WNT5a expression in the SC/ASC or AC patients were negatively correlated with the postoperative survival rate and positively correlated with mortality, which are risk factors and independent prognostic predictors. CONCLUSION SC/ASC or AC patients with positive ROR2 or WNT5a expression generally have a poor prognosis. PMID:28465645

Ferroresonant flux coupled battery charger

NASA Technical Reports Server (NTRS)

McLyman, Colonel W. T. (Inventor)

1987-01-01

A battery charger for incorporation into an electric-powered vehicle is disclosed. The charger includes a ferroresonant voltage-regulating circuit for providing an output voltage proportional to the frequency of an input AC voltage. A high frequency converter converts a DC voltage supplied, for example, from a rectifier connected to a standard AC outlet, to a controlled frequency AC voltage which is supplied to the input of the ferroresonant circuit. The ferroresonant circuit includes an output, a saturable core transformer connected across the output, and a first linear inductor and a capacitor connected in series across the saturable core transformer and tuned to resonate at the third harmonic of the AC voltage from the high frequency converter. The ferroresonant circuit further includes a second linear inductor connected between the input of the ferroresonant circuit and the saturable core transformer. The output voltage from the ferroresonant circuit is rectified and applied across a pair of output terminals adapted to be connected to the battery to be charged. A feedback circuit compares the voltage across the output terminals with a reference voltage and controls the frequency of the AC voltage produced by the high frequency converter to maintain the voltage across the output terminals at a predetermined value. The second linear inductor provides a highly reactive load in the event of a fault across the output terminals to render the charger short-circuit proof.

Hispanic residential ethnic density and depression in post-acute coronary syndrome patients: Re-thinking the role of social support.

PubMed

Denton, Ellen-Ge D; Shaffer, Jonathan A; Alcantara, Carmela; Clemow, Lynn; Brondolo, Elizabeth

2015-05-01

The ethnic density hypothesis suggests that ethnic density confers greater social support and consequently protects against depressive symptoms in ethnic minority individuals. However, the potential benefits of ethnic density have not been examined in individuals who are facing a specific and salient life stressor. We examined the degree to which the effects of Hispanic ethnic density on depressive symptoms are explained by socioeconomic resources and social support. Patients with acute coronary syndrome (ACS, N = 472) completed the Beck Depression Inventory (BDI) and measures of demographics, ACS clinical factors and perceived social support. Neighborhood characteristics, including median income, number of single parent households and Hispanic ethnic density, were extracted from the American Community Survey Census (2005-2009) for each patient using his or her geocoded address. In a linear regression analysis adjusted for demographic and clinical factors, Hispanic ethnic density was positively associated with depressive symptoms (β = .09, standard error (SE) = .04, p = .03). However, Hispanic density was no longer a significant predictor of depressive symptoms when neighborhood characteristics were controlled. The relationship of Hispanic density on depressive symptoms was moderated by nativity status. Among US-born patients with ACS, there was a significant positive relationship between Hispanic density and depressive symptoms and social support significantly mediated this effect. There was no observed effect of Hispanic density to depressive symptoms for foreign-born ACS patients. Although previous research suggests that ethnic density may be protective against depression, our data suggest that among patients with ACS, living in a community with a high concentration of Hispanic individuals is associated with constrained social and economic resources that are themselves associated with greater depressive symptoms. These data add to a growing body of literature on the effects of racial or ethnic segregation on health outcomes. © The Author(s) 2014.

The Group Selection or Assessment Centre (AC) Approach to Personnel Selection: An Annotated Bibliography,

DTIC Science & Technology

1988-02-01

sponsors of ACs, e.g. their cost in terms of the time lost by senior managers because of their partici.nnts as assessors. Emhasises the need to address...American Psychologist. 37, 180-189. Reports use of the AC method to study the progress of a group of managers over a period of time . The study included...on 254 managers attending an AC, for changes in validities over time . Peer and assessor ratings, along with linear combinations, were found

AC conductivity and dielectric behavior of bulk Furfurylidenemalononitrile

NASA Astrophysics Data System (ADS)

El-Nahass, M. M.; Ali, H. A. M.

2012-06-01

AC conductivity and dielectric behavior for bulk Furfurylidenemalononitrile have been studied over a temperature range (293-333 K) and frequency range (50-5×106 Hz). The frequency dependence of ac conductivity, σac, has been investigated by the universal power law, σac(ω)=Aωs. The variation of the frequency exponent (s) with temperature was analyzed in terms of different conduction mechanisms, and it was found that the correlated barrier hopping (CBH) model is the predominant conduction mechanism. The temperature dependence of σac(ω) showed a linear increase with the increase in temperature at different frequencies. The ac activation energy was determined at different frequencies. Dielectric data were analyzed using complex permittivity and complex electric modulus for bulk Furfurylidenemalononitrile at various temperatures.

Experimental investigation of SDBD plasma actuator driven by AC high voltage with a superimposed positive pulse bias voltage

NASA Astrophysics Data System (ADS)

Qi, Xiao-Hua; Yan, Hui-Jie; Yang, Liang; Hua, Yue; Ren, Chun-Sheng

2017-08-01

In this work, a driven voltage consisting of AC high voltage with a superimposed positive pulse bias voltage ("AC+ Positive pulse bias" voltage) is adopted to study the performance of a surface dielectric barrier discharge plasma actuator under atmospheric conditions. To compare the performance of the actuator driven by single-AC voltage and "AC+ Positive pulse bias" voltage, the actuator-induced thrust force and power consumption are measured as a function of the applied AC voltage, and the measured results indicate that the thrust force can be promoted significantly after superimposing the positive pulse bias voltage. The physical mechanism behind the thrust force changes is analyzed by measuring the optical properties, electrical characteristics, and surface potential distribution. Experimental results indicate that the glow-like discharge in the AC voltage half-cycle, next to the cycle where a bias voltage pulse has been applied, is enhanced after applying the positive pulse bias voltage, and this perhaps is the main reason for the thrust force increase. Moreover, surface potential measurement results reveal that the spatial electric field formed by the surface charge accumulation after positive pulse discharge can significantly affect the applied external electric field, and this perhaps can be responsible for the experimental phenomenon that the decrease of thrust force is delayed by pulse bias voltage action after the filament discharge occurs in the glow-like discharge region. The schlieren images further verify that the actuator-induced airflow velocity increases with the positive pulse voltage.

Context based computational analysis and characterization of ARS consensus sequences (ACS) of Saccharomyces cerevisiae genome.

PubMed

Singh, Vinod Kumar; Krishnamachari, Annangarachari

2016-09-01

Genome-wide experimental studies in Saccharomyces cerevisiae reveal that autonomous replicating sequence (ARS) requires an essential consensus sequence (ACS) for replication activity. Computational studies identified thousands of ACS like patterns in the genome. However, only a few hundreds of these sites act as replicating sites and the rest are considered as dormant or evolving sites. In a bid to understand the sequence makeup of replication sites, a content and context-based analysis was performed on a set of replicating ACS sequences that binds to origin-recognition complex (ORC) denoted as ORC-ACS and non-replicating ACS sequences (nrACS), that are not bound by ORC. In this study, DNA properties such as base composition, correlation, sequence dependent thermodynamic and DNA structural profiles, and their positions have been considered for characterizing ORC-ACS and nrACS. Analysis reveals that ORC-ACS depict marked differences in nucleotide composition and context features in its vicinity compared to nrACS. Interestingly, an A-rich motif was also discovered in ORC-ACS sequences within its nucleosome-free region. Profound changes in the conformational features, such as DNA helical twist, inclination angle and stacking energy between ORC-ACS and nrACS were observed. Distribution of ACS motifs in the non-coding segments points to the locations of ORC-ACS which are found far away from the adjacent gene start position compared to nrACS thereby enabling an accessible environment for ORC-proteins. Our attempt is novel in considering the contextual view of ACS and its flanking region along with nucleosome positioning in the S. cerevisiae genome and may be useful for any computational prediction scheme.

MR Imaging-Guided Attenuation Correction of PET Data in PET/MR Imaging.

PubMed

Izquierdo-Garcia, David; Catana, Ciprian

2016-04-01

Attenuation correction (AC) is one of the most important challenges in the recently introduced combined PET/magnetic resonance (MR) scanners. PET/MR AC (MR-AC) approaches aim to develop methods that allow accurate estimation of the linear attenuation coefficients of the tissues and other components located in the PET field of view. MR-AC methods can be divided into 3 categories: segmentation, atlas, and PET based. This review provides a comprehensive list of the state-of-the-art MR-AC approaches and their pros and cons. The main sources of artifacts are presented. Finally, this review discusses the current status of MR-AC approaches for clinical applications. Copyright © 2016 Elsevier Inc. All rights reserved.

Superconductor disks and cylinders in an axial magnetic field: II. Nonlinear and linear ac susceptibilities

NASA Astrophysics Data System (ADS)

Brandt, Ernst Helmut

1998-09-01

The ac susceptibility χ=χ'-iχ'' of superconductor cylinders of finite length in a magnetic field applied along the cylinder axis is calculated using the method developed in the preceding paper, part I. This method does not require any approximation of the infinitely extended magnetic field outside the cylinder or disk but directly computes the current density J inside the superconductor. The material is characterized by a general current-voltage law E(J), e.g., E(J)=Ec[J/Jc(B)]n(B), where E is the electric field, B=μ0H the magnetic induction, Ec a prefactor, Jc the critical current density, and n>=1 the creep exponent. For n>1, the nonlinear ac susceptibility is calculated from the hysteresis loops of the magnetic moment of the cylinder, which is obtained by time integration of the equation for J(r,t). For n>>1 these results go over into the Bean critical state model. For n=1, and for any linear complex resistivity ρac(ω)=E/J, the linear ac susceptibility is calculated from an eigenvalue problem which depends on the aspect ratio b/a of the cylinder or disk. In the limits b/a<<1 and b/a>>1, the known results for thin disks in a perpendicular field and long cylinders in a parallel field are reproduced. For thin disks in a perpendicular field, at large frequencies χ(ω) crosses over to the behavior of slabs in parallel geometry since the magnetic field lines are expelled and have to flow around the disk. The results presented may be used to obtain the nonlinear or linear resistivity from contact-free magnetic measurements on superconductors of realistic shape.

External Magnetic Field Reduction Techniques for the Advanced Stirling Radioisotope Generator

NASA Technical Reports Server (NTRS)

Niedra, Janis M.; Geng, Steven M.

2013-01-01

Linear alternators coupled to high efficiency Stirling engines are strong candidates for thermal-to-electric power conversion in space. However, the magnetic field emissions, both AC and DC, of these permanent magnet excited alternators can interfere with sensitive instrumentation onboard a spacecraft. Effective methods to mitigate the AC and DC electromagnetic interference (EMI) from solenoidal type linear alternators (like that used in the Advanced Stirling Convertor) have been developed for potential use in the Advanced Stirling Radioisotope Generator. The methods developed avoid the complexity and extra mass inherent in data extraction from multiple sensors or the use of shielding. This paper discusses these methods, and also provides experimental data obtained during breadboard testing of both AC and DC external magnetic field devices.

Neighborhood matters: the impact of Hispanic ethnic density on future depressive symptoms 1-year following an ACS event among Hispanic patients.

PubMed

Denton, Ellen-Ge D; Shaffer, Jonathan A; Alcantara, Carmela; Cadermil, Esteban

2016-02-01

The Ethnic Density hypothesis posits that living around others from similar ethnic backgrounds reduces the risk of adverse mental health outcomes such as depression. Contrary to this hypothesis, previous work has shown that Hispanic ethnic density is cross-sectionally associated with increased depressive symptom severity among patients hospitalized with an acute coronary syndrome (ACS; myocardial infarction or unstable angina pectoris). To date, no study has examined the prospective association of Hispanic ethnic density on long-term depressive symptom severity following an acute medical event. We prospectively assessed the impact of Hispanic ethnic density on depressive symptoms, 1-year following an ACS event, among Hispanic adult patients. We tested the non-linear association between ethnic density and depressive symptoms to account for inconsistent findings on the ethnic density hypothesis. At the time of an index ACS event (i.e., baseline, N = 326) and 1-year later (N = 252), Hispanic patients from the Prescription Usage, Lifestyle, and Stress Evaluation prospective cohort study completed the Beck Depression Inventory as a measure of depressive symptom severity. Hispanic ethnic density was defined by the percentage of Hispanic residents within each patient's census tract using data extracted from the American Community Survey Census (2010-2013). Covariates included baseline demographic factors (age, gender, English fluency, education, nativity status), cardiovascular factors (Charlson comorbidity index, left ventricular ejection fraction, Global Registry of Acute Coronary Events 6-month prognostic risk score), and neighborhood factors (residential density, income, and percentage of households receiving public assistance). In an adjusted multivariable linear regression analysis there was a significant curvilinear association between Hispanic ethnic density and depressive symptom severity at 1 year. As Hispanic ethnic density increased from low to moderate density, there was an increase in depressive symptoms, but depressive symptoms slightly declined in census tracts with the highest density of Hispanics. Furthermore, gender significantly moderated the relation between Hispanic ethnic density and 1-year depressive symptom severity, such that Hispanic ethnic density was significantly associated with increased depressive symptom severity for female Hispanic patients with ACS, but not for male Hispanic patients. Previous research suggests that ethnic density may be protective against depression in Hispanic enclaves; however, our findings suggest a non-linear ethnic density effect and an overall more complex association between ethnic density and depression. These data add to a growing body of literature on the effects of sociodemographic and contextual factors on health.

Neighborhood matters: the impact of Hispanic ethnic density on future depressive symptoms 1-year following an ACS event among Hispanic patients

PubMed Central

Denton, Ellen-ge D.; Shaffer, Jonathan A.; Alcantara, Carmela; Cadermil, Esteban

2015-01-01

The Ethnic Density hypothesis posits that living around others from similar ethnic backgrounds reduces the risk of adverse mental health outcomes such as depression. Contrary to this hypothesis, previous work has shown that Hispanic ethnic density is cross-sectionally associated with increased depressive symptom severity among patients hospitalized with an acute coronary syndrome (ACS; myocardial infarction or unstable angina pectoris). To date, no study has examined the prospective association of Hispanic ethnic density on long-term depressive symptom severity following an acute medical event. We prospectively assessed the impact of Hispanic ethnic density on depressive symptoms, 1-year following an ACS event, among Hispanic adult patients. We tested the non-linear association between ethnic density and depressive symptoms to account for inconsistent findings on the ethnic density hypothesis. At the time of an index ACS event (i.e., baseline, N = 326) and 1-year later (N = 252), Hispanic patients from the Prescription Usage, Lifestyle, and Stress Evaluation prospective cohort study completed the Beck Depression Inventory as a measure of depressive symptom severity. Hispanic ethnic density was defined by the percentage of Hispanic residents within each patient's census tract using data extracted from the American Community Survey Census (2010–2013). Covariates included baseline demographic factors (age, gender, English fluency, education, nativity status), cardiovascular factors (Charlson comorbidity index, left ventricular ejection fraction, Global Registry of Acute Coronary Events 6-month prognostic risk score), and neighborhood factors (residential density, income, and percentage of households receiving public assistance). In an adjusted multivariable linear regression analysis there was a significant curvilinear association between Hispanic ethnic density and depressive symptom severity at 1 year. As Hispanic ethnic density increased from low to moderate density, there was an increase in depressive symptoms, but depressive symptoms slightly declined in census tracts with the highest density of Hispanics. Furthermore, gender significantly moderated the relation between Hispanic ethnic density and 1-year depressive symptom severity, such that Hispanic ethnic density was significantly associated with increased depressive symptom severity for female Hispanic patients with ACS, but not for male Hispanic patients. Previous research suggests that ethnic density may be protective against depression in Hispanic enclaves; however, our findings suggest a non-linear ethnic density effect and an overall more complex association between ethnic density and depression. These data add to a growing body of literature on the effects of sociodemographic and contextual factors on health. PMID:26407692

The Association between Anticholinergic Drug Use and Rehabilitation Outcome in Post-Acute Hip Fractured Patients: A Retrospective Cohort Study.

PubMed

Hershkovitz, Avital; Angel, Corina; Brill, Shai; Nissan, Ran

2018-04-01

Anticholinergic (AC) drugs are associated with significant impairment in cognitive and physical function which may affect rehabilitation in older people. We aimed to evaluate whether AC burden is associated with rehabilitation achievement in post-acute hip-fractured patients. A retrospective cohort study carried out in a post-acute geriatric rehabilitation center on 1019 hip-fractured patients admitted from January 2011 to October 2015. The Anticholinergic Cognitive Burden Scale (ACB) was used to quantify the AC burden. Main outcome measures included the Functional Independence Measure (FIM) instrument, motor FIM (mFIM), Montebello Rehabilitation Factor Score (MRFS) on the mFIM, and length of stay (LOS). The study population was divided into two groups: individuals with low admission AC burden (ACB ≤ 1) and those with high admission AC burden (ACB ≥ 2). The relationship between the admission AC burden and clinical, demographic and comorbidity variables was assessed using the Mann-Whitney and Chi square tests. A multiple linear regression model was used to estimate the association between admission AC burden and discharge FIM score after controlling for sociodemographic characteristics and chronic diseases. Patients with a high admission AC burden had a significantly higher rate of high education, a significantly lower rate reside at home, they waited a longer period of time from surgery to rehabilitation, were less independent pre-fracture, and presented with a higher rate of vascular disorders and depression compared with patients with a lower admission AC burden. These patients also exhibited a significantly lower FIM score on admission and at discharge, a lower FIM score change, and a lower achievement on the MRFS compared with patients with a lower admission AC burden. A multiple linear regression analysis showed that admission AC burden was significantly associated with the discharge FIM score after adjustment for confounding variables. High admission AC drug burden is significantly associated with less favorable discharge functional status in post-acute hip-fractured patients, independent of relevant risk factors.

A Global Circuit Diagram to Contrast the Behavior of the DC and AC Global Circuits

NASA Astrophysics Data System (ADS)

Williams, E.; Boldi, R. A.; Markson, R. J.

2017-12-01

The Earth-ionosphere cavity is home to both the classical DC and the AC (Schumann resonances) global circuits. The predominant source for the AC global circuit is lightning, but the sources for the DC global circuit source remains controversial. Separate measurements over many years have shown that the amplitude variation of global lightning and the AC global circuit is about twice that of the DC global circuit on both the diurnal and annual time scales. A global diagram is used to shed further light on this result and to explore the co-variation of the two global circuits. Actual measurements of the ionospheric potential (Vi) are plotted against the simultaneous global lightning flash rate F. The latter estimates are drawn from a global climatology of LIS/OTD satellite observations (Cecil et al., 2014) giving flash rate as a function of both Day of Year and UT time, and are used as best guesses for F at the time of the Vi observations. A least-squares linear fit through the data points on this diagram show a zero-flash-rate intercept for Vi that is more than half of the mean Vi ( 250 kV). This result suggests that electrified shower clouds (without lightning), possibly supplemented by convective transport of positive space charge in the marine boundary layer, are playing a greater role in driving the DC global circuit than previously suspected.

AC impedance analysis of polypyrrole thin films

NASA Technical Reports Server (NTRS)

Penner, Reginald M.; Martin, Charles R.

1987-01-01

The AC impedance spectra of thin polypyrrole films were obtained at open circuit potentials from -0.4 to 0.4 V vs SCE. Two limiting cases are discussed for which simplified equivalent circuits are applicable. At very positive potentials, the predominantly nonfaradaic AC impedance of polypyrrole is very similar to that observed previously for finite porous metallic films. Modeling of the data with the appropriate equivalent circuit permits effective pore diameter and pore number densities of the oxidized film to be estimated. At potentials from -0.4 to -0.3 V, the polypyrrole film is essentially nonelectronically conductive and diffusion of polymer oxidized sites with their associated counterions can be assumed to be linear from the film/substrate electrode interface. The equivalent circuit for the polypyrrole film at these potentials is that previously described for metal oxide, lithium intercalation thin films. Using this model, counterion diffusion coefficients are determined for both semi-infinite and finite diffusion domains. In addition, the limiting low frequency resistance and capacitance of the polypyrrole thin fims was determined and compared to that obtained previously for thicker films of the polymer. The origin of the observed potential dependence of these low frequency circuit components is discussed.

Determination of Noncovalent Binding Using a Continuous Stirred Tank Reactor as a Flow Injection Device Coupled to Electrospray Ionization Mass Spectrometry

NASA Astrophysics Data System (ADS)

Santos, Inês C.; Waybright, Veronica B.; Fan, Hui; Ramirez, Sabra; Mesquita, Raquel B. R.; Rangel, António O. S. S.; Fryčák, Petr; Schug, Kevin A.

2015-07-01

Described is a new method based on the concept of controlled band dispersion, achieved by hyphenating flow injection analysis with ESI-MS for noncovalent binding determinations. A continuous stirred tank reactor (CSTR) was used as a FIA device for exponential dilution of an equimolar host-guest solution over time. The data obtained was treated for the noncovalent binding determination using an equimolar binding model. Dissociation constants between vancomycin and Ac-Lys(Ac)-Ala-Ala-OH peptide stereoisomers were determined using both the positive and negative ionization modes. The results obtained for Ac- L-Lys(Ac)- D-Ala- D-Ala (a model for a Gram-positive bacterial cell wall) binding were in reasonable agreement with literature values made by other mass spectrometry binding determination techniques. Also, the developed method allowed the determination of dissociation constants for vancomycin with Ac- L-Lys(Ac)- D-Ala- L-Ala, Ac- L-Lys(Ac)- L-Ala- D-Ala, and Ac- L-Lys(Ac)- L-Ala- L-Ala. Although some differences in measured binding affinities were noted using different ionization modes, the results of each determination were generally consistent. Differences are likely attributable to the influence of a pseudo-physiological ammonium acetate buffer solution on the formation of positively- and negatively-charged ionic complexes.

Academic stress and positive affect: Asian value and self-worth contingency as moderators among Chinese international students.

PubMed

Liao, Kelly Yu-Hsin; Wei, Meifen

2014-01-01

The theoretical model proposed by Berry and colleagues (Berry, 1997; Berry, Kim, Minde, & Mok, 1987) highlights the importance of identifying moderators in the acculturation process. Accordingly, the current study examined the Asian cultural value of family recognition through achievement (FRTA) and contingency of self-worth on academic competence (CSW-AC) as moderators in the association between academic stress and positive affect among Chinese international students. A total of 370 Chinese international students completed online surveys. Results from a hierarchical regression indicated that while academic stress was negatively associated with positive affect, FRTA was positively associated with positive affect. In other words, those with high academic stress reported a lower level of positive affect. However, individuals who endorsed high levels of FRTA reported a higher level of positive affect. In addition, results also revealed a significant interaction between academic stress and CSW-AC on positive affect. Thus, the study's finding supported the moderator role of CSW-AC. Simple effect analyses were conducted to examine the significant interaction. The results showed that higher levels of CSW-AC strengthened the negative association between academic stress and positive affect but lower levels of CSW-AC did not. Future research directions and implications are discussed.

Development of Monoclonal Antibodies Recognizing Linear Epitope: Illustration by Three Bacillus thuringiensis Crystal Proteins of Genetically Modified Cotton, Maize, and Tobacco.

PubMed

Cao, Zhen; Zhang, Wei; Ning, Xiangxue; Wang, Baomin; Liu, Yunjun; Li, Qing X

2017-11-22

Bacillus thuringiensis Cry1Ac, Cry1Ia1, and Cry1Ie are δ-endotoxin insecticidal proteins widely implemented in genetically modified organisms (GMO), such as cotton, maize, and potato. Western blot assay integrates electrophoresis separation power and antibody high specificity for monitoring specific exogenous proteins expressed in GMO. Procedures for evoking monoclonal antibody (mAb) for Western blot were poorly documented. In the present study, Cry1Ac partially denatured at 100 °C for 5 min was used as an immunogen to develop mAbs selectively recognizing a linear epitope of Cry1Ac for Western blot. mAb 5E9C6 and 3E6E2 selected with sandwich ELISA strongly recognized the heat semidenatured Cry1Ac. Particularly, 3E6E2 recognized both E. coli and cotton seed expressed Cry1Ac in Western blot. Such strategy of using partially denatured proteins as immunogens and using sandwich ELISA for mAb screening was also successfully demonstrated with production of mAbs against Cry1Ie for Western blot assay in maize.

Alternating current corona discharge/atmospheric pressure chemical ionization for mass spectrometry.

PubMed

Habib, Ahsan; Usmanov, Dilshadbek; Ninomiya, Satoshi; Chen, Lee Chuin; Hiraoka, Kenzo

2013-12-30

Although alternating current (ac) corona discharge has been widely used in the fields of material science and technology, no reports have been published on its application to an atmospheric pressure chemical ionization (APCI) ion source. In this work, ac corona discharge for an APCI ion source has been examined for the first time. The ambient atmospheric pressure ac corona discharge (15 kHz, 2.6 kVptp ) was generated by using a stainless steel acupuncture needle. The generated ions were measured using an ion trap mass spectrometer. A comparative study on ac and direct current (dc) corona APCI ion sources was carried out using triacetone triperoxide and trinitrotoluene as test samples. The ac corona discharge gave ion signals as strong as dc corona discharge for both positive and negative ion modes. In addition, softer ionization was obtained with ac corona discharge than with dc corona discharge. The erosion of the needle tip induced by ac corona was less than that obtained with positive mode dc corona. A good 'yardstick' for assessing ac corona is that it can be used for both positive and negative ion modes without changing the polarity of the high-voltage power supply. Thus, ac corona can be an alternative to conventional dc corona for APCI ion sources. Copyright © 2013 John Wiley & Sons, Ltd.

Quantitative analysis of MRI-guided attenuation correction techniques in time-of-flight brain PET/MRI.

PubMed

Mehranian, Abolfazl; Arabi, Hossein; Zaidi, Habib

2016-04-15

In quantitative PET/MR imaging, attenuation correction (AC) of PET data is markedly challenged by the need of deriving accurate attenuation maps from MR images. A number of strategies have been developed for MRI-guided attenuation correction with different degrees of success. In this work, we compare the quantitative performance of three generic AC methods, including standard 3-class MR segmentation-based, advanced atlas-registration-based and emission-based approaches in the context of brain time-of-flight (TOF) PET/MRI. Fourteen patients referred for diagnostic MRI and (18)F-FDG PET/CT brain scans were included in this comparative study. For each study, PET images were reconstructed using four different attenuation maps derived from CT-based AC (CTAC) serving as reference, standard 3-class MR-segmentation, atlas-registration and emission-based AC methods. To generate 3-class attenuation maps, T1-weighted MRI images were segmented into background air, fat and soft-tissue classes followed by assignment of constant linear attenuation coefficients of 0, 0.0864 and 0.0975 cm(-1) to each class, respectively. A robust atlas-registration based AC method was developed for pseudo-CT generation using local weighted fusion of atlases based on their morphological similarity to target MR images. Our recently proposed MRI-guided maximum likelihood reconstruction of activity and attenuation (MLAA) algorithm was employed to estimate the attenuation map from TOF emission data. The performance of the different AC algorithms in terms of prediction of bones and quantification of PET tracer uptake was objectively evaluated with respect to reference CTAC maps and CTAC-PET images. Qualitative evaluation showed that the MLAA-AC method could sparsely estimate bones and accurately differentiate them from air cavities. It was found that the atlas-AC method can accurately predict bones with variable errors in defining air cavities. Quantitative assessment of bone extraction accuracy based on Dice similarity coefficient (DSC) showed that MLAA-AC and atlas-AC resulted in DSC mean values of 0.79 and 0.92, respectively, in all patients. The MLAA-AC and atlas-AC methods predicted mean linear attenuation coefficients of 0.107 and 0.134 cm(-1), respectively, for the skull compared to reference CTAC mean value of 0.138cm(-1). The evaluation of the relative change in tracer uptake within 32 distinct regions of the brain with respect to CTAC PET images showed that the 3-class MRAC, MLAA-AC and atlas-AC methods resulted in quantification errors of -16.2 ± 3.6%, -13.3 ± 3.3% and 1.0 ± 3.4%, respectively. Linear regression and Bland-Altman concordance plots showed that both 3-class MRAC and MLAA-AC methods result in a significant systematic bias in PET tracer uptake, while the atlas-AC method results in a negligible bias. The standard 3-class MRAC method significantly underestimated cerebral PET tracer uptake. While current state-of-the-art MLAA-AC methods look promising, they were unable to noticeably reduce quantification errors in the context of brain imaging. Conversely, the proposed atlas-AC method provided the most accurate attenuation maps, and thus the lowest quantification bias. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparative histological and immunohistochemical study of ameloblastomas and ameloblastic carcinomas

PubMed Central

Mosqueda-Taylor, Adalberto; Carlos-Bregni, Román; Pires, Fabio-Ramoa; Delgado-Azañero, Wilson; Neves-Silva, Rodrigo; Aldape-Barrios, Beatriz; Paes-de Almeida, Oslei

2017-01-01

Background This study aimed to compare the histological and immunohistochemical characteristics of ameloblastomas (AM) and ameloblastic carcinomas (AC). Material and Methods Fifteen cases of AM and 9 AC were submitted to hematoxilin and eosin (H&E) and immunohistochemical analysis with the following antibodies: cytokeratins 5,7,8,14 and 19, Ki-67, p53, p63 and the cellular adhesion molecules CD138 (Syndecan-1), E-cadherin and β-catenin. The mean score of the expression of Ki-67 and p53 labelling index (LIs) were compared between the groups using the t test. A value of p<0.05 was considered to be statistically significant. Results All cases were positive for CKs 5, 14 and 19, but negative for CKs 7 and 8. CKs 5 and 19 were positive mainly in the central regions of the ameloblastic islands, while the expression in AC was variable in intensity and localization. CK14 was also variably expressed in both AM and AC. Ki-67 (P=.001) and p53 (P=.004) immunoexpression was higher in AC. All cases were positive for p63, but values were higher in AC. CD138 was mainly expressed in peripheral cells of AM, with a weak positivity in the central areas, while it was positive in most areas of ACs, except in less differentiated regions, where expression was decreased or lost. E-cadherin and β-catenin were weakly positive in both AM and AC. Conclusions These results shows that Ki-67, p53 and p63 expression was higher in AC as compared to AM, suggesting that these markers can be useful when considering diagnosis of malignancy, and perhaps could play a role in malignant transformation of AM. Pattern of expression of CKs 5 and 19 in AC were different to those found in AM, suggesting genetic alterations of these proteins in malignant cells. It was confirmed that CK19 is a good marker for benign odontogenic tumors, such as AM, but it is variably expressed in malignant cases. Key words:Ameloblastoma, ameloblastic carcinoma, immunohistochemistry, odontogenic tumors. PMID:28390135

Amorphous ribbon transducers

NASA Astrophysics Data System (ADS)

Meydan, T.; Overshott, K. J.

1984-02-01

Amorphous ribbon transducers have been investigated which consist of toroidally wound amorphous ribbon with a primary (magnetizing) winding and secondary (search coil) windings. The application of a force to the ribbon gives a linear search coil voltage against applied force characteristic. The positioning of the windings with respect to the applied force has been studied, and it is shown that the effect of the applied force is localized. Domain studies have shown that the applied force produces domain wall motion which can be correlated to the performance. These results have elucidated the operation of ac amorphous ribbon transducers and enabled improved designs to be produced.

Comparison of Short-Term Effects of Diquafosol and Rebamipide on Mucin 5AC Level on the Rabbit Ocular Surface.

PubMed

Hori, Yuichi; Kageyama, Tomofumi; Sakamoto, Asuka; Shiba, Tomoaki; Nakamura, Masatsugu; Maeno, Takatoshi

To investigate the short-term effects of 2 new secretagogue eye drops for dry eye, 3% diquafosol tetrasodium ophthalmic solution (diquafosol) and 2% rebamipide ophthalmic suspension (rebamipide), on the concentration of mucin 5AC (MUC5AC) in rabbit tear fluid and conjunctival goblet cells. One dose of artificial tears, diquafosol or rebamipide, was instilled into 8 eyes of Japanese white rabbits. MUC5AC concentration in the tear fluid was examined using the enzyme-linked immunosorbent assay 15 min after instillation and compared with 8 untreated controls. Impression cytology was performed to measure the number of periodic acid Schiff (PAS)-positive cells and the ratio of the PAS-positive area using image analysis software. Statistical comparison was performed using ANOVA with post hoc analysis with the Tukey's test. After 15 min, only diquafosol significantly (P ≤ 0.01) increased the MUC5AC level in the tear fluid. Although no drug affected the number of PAS-positive cells, the ratio of the PAS-positive area decreased significantly (P ≤ 0.01) only in the diquafosol group. These data indicated that more PAS-positive MUC5AC was released into the tear fluid from the goblet cells by diquafosol than by rebamipide. There is a difference in the induction pattern of MUC5AC into the tears from the goblet cells between these eye drops.

Diffusion tensor imaging of anterior commissural fibers in patients with schizophrenia.

PubMed

Choi, Hongyoon; Kubicki, Marek; Whitford, Thomas J; Alvarado, Jorge L; Terry, Douglas P; Niznikiewicz, Margaret; McCarley, Robert W; Kwon, Jun Soo; Shenton, Martha E

2011-08-01

Alterations in white matter connections in schizophrenia have been investigated using diffusion tensor imaging (DTI). There is also evidence from post-mortem studies as well as from magnetic resonance imaging morphometry studies that the anterior commissure (AC) might be implicated in schizophrenia, but no studies, to date, have investigated the AC using DTI or tractography. DTI scans were analyzed from 25 patients and 23 controls. Mean fractional anisotropy (FA) and trace were measured from the AC tracts. SANS and SAPS were used to evaluate clinical symptoms, and the Iowa Gambling Task, related to decision making, was also examined. Results revealed a significant decrease in mean FA and a significant increase in mean trace of AC tracts in patients compared with controls. In addition, patients, but not controls, showed a negative correlation between age and AC integrity. Statistically significant positive correlations were also found between AC FA and total positive symptom score. Decision making was negatively correlated with FA in patients on the Iowa Gambling Task, but not in controls. This study provides quantitative evidence for a reduction of interhemispheric connectivity in schizophrenia within the AC. Negative correlation between age and AC FA in the patients is consistent with the idea that schizophrenia may be a disorder of white matter maturation. Positive correlation between FA and positive symptom is discussed in the context of white matter's established role in modulating neural conduction velocity. Published by Elsevier B.V.

Application of linear mixed-effects model with LASSO to identify metal components associated with cardiac autonomic responses among welders: a repeated measures study

PubMed Central

Zhang, Jinming; Cavallari, Jennifer M; Fang, Shona C; Weisskopf, Marc G; Lin, Xihong; Mittleman, Murray A; Christiani, David C

2017-01-01

Background Environmental and occupational exposure to metals is ubiquitous worldwide, and understanding the hazardous metal components in this complex mixture is essential for environmental and occupational regulations. Objective To identify hazardous components from metal mixtures that are associated with alterations in cardiac autonomic responses. Methods Urinary concentrations of 16 types of metals were examined and ‘acceleration capacity’ (AC) and ‘deceleration capacity’ (DC), indicators of cardiac autonomic effects, were quantified from ECG recordings among 54 welders. We fitted linear mixed-effects models with least absolute shrinkage and selection operator (LASSO) to identify metal components that are associated with AC and DC. The Bayesian Information Criterion was used as the criterion for model selection procedures. Results Mercury and chromium were selected for DC analysis, whereas mercury, chromium and manganese were selected for AC analysis through the LASSO approach. When we fitted the linear mixed-effects models with ‘selected’ metal components only, the effect of mercury remained significant. Every 1 µg/L increase in urinary mercury was associated with −0.58 ms (−1.03, –0.13) changes in DC and 0.67 ms (0.25, 1.10) changes in AC. Conclusion Our study suggests that exposure to several metals is associated with impaired cardiac autonomic functions. Our findings should be replicated in future studies with larger sample sizes. PMID:28663305

The AC 2000.2 Catalogue

NASA Astrophysics Data System (ADS)

Urban, S. E.; Corbin, T. E.; Wycoff, G. L.; Makarov, V. V.; Høg, E.; Fabricius, C.

2001-12-01

For over 100 years, the international project known as the Astrographic Catalogue -- which involved 20 observatories tasked to photograph the sky -- has held an unfulfilled promised of yielding a wealth of astrometric information. This promise was not realized due to the inadequate reductions of the project's plates. However, in 1997 the U.S. Naval Observatory (USNO) completed the reductions of the 22,660 plates. That catalogue, named the AC 2000, contained positions and magnitudes for 4.6 million stars down to about v magnitude 12.5. Due to the early epochs of the data -- averaging 1907 -- and the positional accuracies -- between 150 and 400 milliarcseconds -- the data are extremely valuable in computing proper motions. In 1997, these positions were used to form the proper motions of the ACT Reference Catalogue. In 1999, USNO and Copenhagen University Observatory (CUO) partnered to create the Tycho-2 Catalogue. The CUO group re-analyzed the data from the Tycho experiment on the Hipparcos satellite. The USNO group re-analyzed over 140 positional catalogs which were combined with the expanded Tycho positions from the CUO group to compute the Tycho-2 proper motions. The largest contributor to these proper motions was the re-analyzed Astrographic Catalogue; the latest version being known as the AC 2000.2 Catalogue. There are two major differences between the AC 2000 and the AC 2000.2. First, the reference catalog used in AC 2000.2 was an expanded version of the Astrographic Catalogue Reference Stars that was rigorously derived on the Hipparcos Celestial Reference Frame. The second is that AC 2000.2 contains photometry from Tycho-2, where available. A description of the AC 2000.2 Catalogue, the reduction techniques used, how it compares with the 1997 version, and information on obtaining the data will be presented.

Immuno-PET Imaging of CD30-Positive Lymphoma Using 89Zr-Desferrioxamine-Labeled CD30-Specific AC-10 Antibody.

PubMed

Rylova, Svetlana N; Del Pozzo, Luigi; Klingeberg, Cathrin; Tönnesmann, Roswitha; Illert, Anna L; Meyer, Philipp T; Maecke, Helmut R; Holland, Jason P

2016-01-01

The CD30-specific antibody-drug conjugate, brentuximab vedotin, is approved for the treatment of relapsed, refractory Hodgkin lymphomas and systemic anaplastic large T-cell lymphomas. Multiple ongoing clinical trials are investigating brentuximab vedotin efficacy in other CD30-positive hematologic malignancies. Because CD30 expression varies among different types of lymphoma and can also change during the course of treatment, companion diagnostic imaging of CD30 could be a valuable tool in optimizing patient-specific brentuximab vedotin treatment regimens. The mouse antihuman CD30 antibody AC-10 was radiolabeled with the positron-emitting radionuclide (89)Zr. The stability and specificity of (89)Zr-desferrioxamine (DFO)-labeled CD30-specific AC-10 antibody ((89)Zr-DFO-AC-10) was evaluated in vitro. The pharmacokinetics of (89)Zr-DFO-AC-10 was studied in BALB/c nude mice bearing subcutaneous human Karpas 299 tumors (CD30-positive model) or A-431 tumors (CD30-negative model) using PET/CT imaging, biodistribution studies, and autoradiography. AC-10 was conjugated with a DFO B chelator and radiolabeled with (89)Zr to give formulated (89)Zr-DFO-AC-10 with a radiochemical yield of 80%, radiochemical purity greater than 99%, and specific activity of 111-148 MBq/mg. (89)Zr-DFO-AC-10 was stable in mouse and human sera and preserved the immunoreactivity toward CD30. Biodistribution data showed the highest tissue accumulation of (89)Zr-DFO-AC-10 in CD30-positive tumors, with 37.9% ± 8.2% injected activity per gram of tissue at 72 h after injection, whereas uptake in CD30-negative tumors was 11.0% ± 0.4%. The specificity of (89)Zr-DFO-AC-10 binding to CD30 in vivo was confirmed by blocking studies. Time-activity curves showed that between 24 and 144 h after injection, tumor-to-muscle ratios increased from 18.9 to 51.8 in the CD30-positive model and from 4.8 to 8.7 in the CD30-negative model. Tumor-to-blood ratios also increased, from 3.2 to 13.6 and from 1 to 2 in the CD30-positive and -negative models, respectively. Our results demonstrate that for measuring CD30 expression, (89)Zr-DFO-AC-10 is a sensitive PET agent with high tumor-to-normal-tissue contrast. (89)Zr-DFO-AC-10 is a promising CD30-imaging radiotracer for clinical translation in patients with various lymphomas and other diseases. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Magnetic resonance imaging-guided attenuation correction of positron emission tomography data in PET/MRI

PubMed Central

Izquierdo-Garcia, David; Catana, Ciprian

2018-01-01

Synopsis Attenuation correction (AC) is one of the most important challenges in the recently introduced combined positron emission tomography/magnetic resonance imaging (PET/MR) scanners. PET/MR AC (MR-AC) approaches aim to develop methods that allow accurate estimation of the linear attenuation coefficients (LACs) of the tissues and other components located in the PET field of view (FoV). MR-AC methods can be divided into three main categories: segmentation-, atlas- and PET-based. This review aims to provide a comprehensive list of the state of the art MR-AC approaches as well as their pros and cons. The main sources of artifacts such as body-truncation, metallic implants and hardware correction will be presented. Finally, this review will discuss the current status of MR-AC approaches for clinical applications. PMID:26952727

A free-piston Stirling engine/linear alternator controls and load interaction test facility

NASA Technical Reports Server (NTRS)

Rauch, Jeffrey S.; Kankam, M. David; Santiago, Walter; Madi, Frank J.

1992-01-01

A test facility at LeRC was assembled for evaluating free-piston Stirling engine/linear alternator control options, and interaction with various electrical loads. This facility is based on a 'SPIKE' engine/alternator. The engine/alternator, a multi-purpose load system, a digital computer based load and facility control, and a data acquisition system with both steady-periodic and transient capability are described. Preliminary steady-periodic results are included for several operating modes of a digital AC parasitic load control. Preliminary results on the transient response to switching a resistive AC user load are discussed.

Characterization of AC current sensor based on giant magnetoresistance and coil for power meter design

NASA Astrophysics Data System (ADS)

Dhani, H. S.; Aminudin, A.; Waslaluddin

2018-05-01

Electric current is the basic variable of measurement in instrumentation system. One of the current measurements had been developed was based on magnetic sensor. Giant Magnetoresistance (GMR) produces an output voltage when it detects the magnetic field from electric current flow. The purpose of this study was to characterize the response of GMR when variation number of coil was given. The characterization was the GMR voltage response to the AC current values from 0.01 A to 5.00 A. The linearity of the relation was reaching saturation point when the magnetic field measured higher than 10.5 Oe at room temperature. As the number of coil increased, the earlier saturation occurred. To see the sensitivity of the sensor response, the data graph was cut off at 1.56 A AC. From this research, we got single coil was ideal to measure electric current higher than 1.56 A AC, as the relation of GMR voltage to the current tended to maintain its linearity. For measurement of 1.56 A AC and less, coil number addition would increase the sensitivity of sensor response. This research hopefully will be benefit for further development using an electric current measurement based on GMR magnetic sensor for power meter design.

Interpersonal violence, alcohol use, and acquired capability for suicide.

PubMed

Wolford-Clevenger, Caitlin; Febres, Jeniimarie; Zapor, Heather; Elmquist, JoAnna; Bliton, Chloe; Stuart, Gregory L

2015-01-01

Acquired capability for suicide (ACS), defined as pain tolerance and fearlessness about death, is theorized as necessary to enact suicide. This study examined the associations of interpersonal violence and alcohol use with ACS in 502 college students. General fearlessness/pain tolerance was positively associated with male gender and alcohol use. Fearlessness about death was positively associated with male gender and general physical violence perpetration. However, these risk factors did not explain variance in ACS beyond male gender and history of suicide attempts/nonsuicidal self-injury. These findings add to the understanding of ACS correlates.

Medium-Range Forecast Skill for Extraordinary Arctic Cyclones in Summer of 2008-2016

NASA Astrophysics Data System (ADS)

Yamagami, Akio; Matsueda, Mio; Tanaka, Hiroshi L.

2018-05-01

Arctic cyclones (ACs) are a severe atmospheric phenomenon that affects the Arctic environment. This study assesses the forecast skill of five leading operational medium-range ensemble forecasts for 10 extraordinary ACs that occurred in summer during 2008-2016. Average existence probability of the predicted ACs was >0.9 at lead times of ≤3.5 days. Average central position error of the predicted ACs was less than half of the mean radius of the 10 ACs (469.1 km) at lead times of 2.5-4.5 days. Average central pressure error of the predicted ACs was 5.5-10.7 hPa at such lead times. Therefore, the operational ensemble prediction systems generally predict the position of ACs within 469.1 km 2.5-4.5 days before they mature. The forecast skill for the extraordinary ACs is lower than that for midlatitude cyclones in the Northern Hemisphere but similar to that in the Southern Hemisphere.

Positional-Species Composition of Diacylglycerol Acetates from Mature Euonymus Seeds.

PubMed

Sidorov, Roman A; Pchelkin, Vasily P; Zhukov, Anatoly V; Tsydendambaev, Vladimir D

2016-06-01

The positional-species composition (PSC) of 3-acetyl-1,2-diacyl-sn-glycerols (AcDAGs) from the seeds of mature fruits of 14 species of the genus Euonymus L. was established. The residues of six major fatty acids (FAs), palmitic (P), stearic (St), hexadecenoic (H), octadecenoic (O), linoleic (L), and linolenic (Ln), were present in the AcDAGs. Here, we demonstrated that the profile of PSC of AcDAGs could serve as chemotaxonomic factor to divide euonymus species studied here into groups which completely correlate with the present day systematic of the genus. In particular, the Euonymus section greatly exceeded other sections of the Euonymus subgenus as well as the Kalonymus one in the total levels of AcDAGs positional species having one and two O residues and was characterized by significantly lesser concentrations of species with one and two L residues. Moreover, in seed, AcDAGs of almost all Euonymus species EFL values were slightly higher than EFO ones, but all EFL and EFO values were higher than 1.0, and therefore, it can be concluded that both FAs mainly esterified sn-2-position of the glycerol moiety and saturated FAs residues were always virtually absent in the sn-2 position of Euonymus seed AcDAGs, as it is also the case in nearly all TAGs molecules of plant origin. © 2016 Verlag Helvetica Chimica Acta AG, Zürich.

Region specific optimization of continuous linear attenuation coefficients based on UTE (RESOLUTE): application to PET/MR brain imaging

NASA Astrophysics Data System (ADS)

Ladefoged, Claes N.; Benoit, Didier; Law, Ian; Holm, Søren; Kjær, Andreas; Højgaard, Liselotte; Hansen, Adam E.; Andersen, Flemming L.

2015-10-01

The reconstruction of PET brain data in a PET/MR hybrid scanner is challenging in the absence of transmission sources, where MR images are used for MR-based attenuation correction (MR-AC). The main challenge of MR-AC is to separate bone and air, as neither have a signal in traditional MR images, and to assign the correct linear attenuation coefficient to bone. The ultra-short echo time (UTE) MR sequence was proposed as a basis for MR-AC as this sequence shows a small signal in bone. The purpose of this study was to develop a new clinically feasible MR-AC method with patient specific continuous-valued linear attenuation coefficients in bone that provides accurate reconstructed PET image data. A total of 164 [18F]FDG PET/MR patients were included in this study, of which 10 were used for training. MR-AC was based on either standard CT (reference), UTE or our method (RESOLUTE). The reconstructed PET images were evaluated in the whole brain, as well as regionally in the brain using a ROI-based analysis. Our method segments air, brain, cerebral spinal fluid, and soft tissue voxels on the unprocessed UTE TE images, and uses a mapping of R2* values to CT Hounsfield Units (HU) to measure the density in bone voxels. The average error of our method in the brain was 0.1% and less than 1.2% in any region of the brain. On average 95% of the brain was within  ±10% of PETCT, compared to 72% when using UTE. The proposed method is clinically feasible, reducing both the global and local errors on the reconstructed PET images, as well as limiting the number and extent of the outliers.

Novel AC Servo Rotating and Linear Composite Driving Device for Plastic Forming Equipment

NASA Astrophysics Data System (ADS)

Liang, Jin-Tao; Zhao, Sheng-Dun; Li, Yong-Yi; Zhu, Mu-Zhi

2017-07-01

The existing plastic forming equipment are mostly driven by traditional AC motors with long transmission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In order to realize high performance forming processes, the driving device should be improved, especially for complicated processing motions. Based on electric servo direct drive technology, a novel AC servo rotating and linear composite driving device is proposed, which features implementing both spindle rotation and feed motion without transmission, so that compact structure and precise control can be achieved. Flux switching topology is employed in the rotating drive component for strong robustness, and fractional slot is employed in the linear direct drive component for large force capability. Then the mechanical structure for compositing rotation and linear motion is designed. A device prototype is manufactured, machining of each component and the whole assembly are presented respectively. Commercial servo amplifiers are utilized to construct the control system of the proposed device. To validate the effectiveness of the proposed composite driving device, experimental study on the dynamic test benches are conducted. The results indicate that the output torque can attain to 420 N·m and the dynamic tracking errors are less than about 0.3 rad in the rotating drive. the dynamic tracking errors are less than about 1.6 mm in the linear feed. The proposed research provides a method to construct high efficiency and accuracy direct driving device in plastic forming equipment.

Positive Illusions? The Accuracy of Academic Self-Appraisals in Adolescents With ADHD.

PubMed

Chan, Todd; Martinussen, Rhonda

2016-08-01

Children with attention deficit/hyperactivity disorder (ADHD) overestimate their academic competencies (AC) relative to performance and informant indicators (i.e., positive illusory bias; PIB). Do adolescents with ADHD exhibit this PIB and does it render self-views inaccurate? We examined the magnitude of the AC-PIB in adolescents with and without ADHD, the predictive accuracy of parent and adolescent AC ratings, and whether executive functions (EF) predict the AC-PIB. Adolescents (49 ADHD; 47 typically developing) completed math and EF tests, and self-rated their AC. Parents rated their adolescents' AC and EF. Adolescents with ADHD performed more poorly on the math task (vs. comparison group) but had a larger AC-PIB relative to parents' ratings. EFs predicted the PIB within the full sample. Adolescents' AC ratings, regardless of ADHD status, were more predictive of math performance than their parents' AC ratings. Adolescents with ADHD appear self-aware in their AC despite a modest PIB; nuanced self-appraisals may depend on EFs. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Autographa californica Multiple Nucleopolyhedrovirus ac83 Gene Contains a cis-Acting Element That Is Essential for Nucleocapsid Assembly.

PubMed

Huang, Zhihong; Pan, Mengjia; Zhu, Silei; Zhang, Hao; Wu, Wenbi; Yuan, Meijin; Yang, Kai

2017-03-01

Baculoviridae is a family of insect-specific viruses that have a circular double-stranded DNA genome packaged within a rod-shaped capsid. The mechanism of baculovirus nucleocapsid assembly remains unclear. Previous studies have shown that deletion of the ac83 gene of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) blocks viral nucleocapsid assembly. Interestingly, the ac83 -encoded protein Ac83 is not a component of the nucleocapsid, implying a particular role for ac83 in nucleocapsid assembly that may be independent of its protein product. To examine this possibility, Ac83 synthesis was disrupted by insertion of a chloramphenicol resistance gene into its coding sequence or by deleting its promoter and translation start codon. Both mutants produced progeny viruses normally, indicating that the Ac83 protein is not required for nucleocapsid assembly. Subsequently, complementation assays showed that the production of progeny viruses required the presence of ac83 in the AcMNPV genome instead of its presence in trans Therefore, we reasoned that ac83 is involved in nucleocapsid assembly via an internal cis -acting element, which we named the nucleocapsid assembly-essential element (NAE). The NAE was identified to lie within nucleotides 1651 to 1850 of ac83 and had 8 conserved A/T-rich regions. Sequences homologous to the NAE were found only in alphabaculoviruses and have a conserved positional relationship with another essential cis -acting element that was recently identified. The identification of the NAE may help to connect the data of viral cis -acting elements and related proteins in the baculovirus nucleocapsid assembly, which is important for elucidating DNA-protein interaction events during this process. IMPORTANCE Virus nucleocapsid assembly usually requires specific cis -acting elements in the viral genome for various processes, such as the selection of the viral genome from the cellular nucleic acids, the cleavage of concatemeric viral genome replication intermediates, and the encapsidation of the viral genome into procapsids. In linear DNA viruses, such elements generally locate at the ends of the viral genome; however, most of these elements remain unidentified in circular DNA viruses (including baculovirus) due to their circular genomic conformation. Here, we identified a nucleocapsid assembly-essential element in the AcMNPV (the archetype of baculovirus) genome. This finding provides an important reference for studies of nucleocapsid assembly-related elements in baculoviruses and other circular DNA viruses. Moreover, as most of the previous studies of baculovirus nucleocapsid assembly have been focused on viral proteins, our study provides a novel entry point to investigate this mechanism via cis -acting elements in the viral genome. Copyright © 2017 American Society for Microbiology.

Plasma firocoxib concentrations after intra-articular injection of autologous conditioned serum prepared from firocoxib positive horses.

PubMed

Ortved, K F; Goodale, M B; Ober, C; Maylin, G A; Fortier, L A

2017-12-01

Orthobiologics such as autologous conditioned serum (ACS) are often used to treat joint disease in horses. Because ACS is generated from the horse's own blood, any medication administered at the time of preparation would likely be present in stored ACS, which could lead to an inadvertent positive drug test following intra-articular (IA) injection. The main objective of this study was to determine if ACS prepared from firocoxib positive horses could result in detectable plasma concentrations of the drug following IA injection. Firocoxib was administered to six horses at 0.1mg/kg PO twice at a 24h interval. Blood was obtained at 4h following the second dose and transferred to a separate syringe (Arthrex IRAP II) for ACS preparation. Plasma and ACS concentrations of firocoxib were analysed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). When horses were confirmed firocoxib negative, 7.5mL of ACS was injected into both tarsocrural joints. Blood samples were collected at 0, 4, 8, 12, 24, and 48h, and firocoxib concentration was measured. Mean (±standard error of the mean, SEM) plasma concentration of firocoxib 4h following the second dose was 33.3±4.72ng/mL. Mean (±SEM) firocoxib concentration in ACS was 35.4±4.47ng/mL. Fourteen days following the second and last dose of firocoxib, mean plasma concentration was below the lower limit of detection (LOD=1ng/mL) in all horses. Following IA injection of ACS, plasma concentrations of firocoxib remained below LOD at all times in all horses. ACS generated from horses with therapeutic plasma concentrations of firocoxib did not contain sufficient firocoxib to lead to a positive plasma drug test following IA administration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Using the Dynamic Model of Affect (DMA) to examine leisure time as a stress coping resource: Taking into account stress severity and gender difference

PubMed Central

Qian, Xinyi Lisa; Yarnal, Careen M.; Almeida, David M.

2014-01-01

Affective complexity (AC) is a marker of psychological well-being. According to the Dynamic Model of Affect (DMA), stressful experiences reduce AC while positive events increase AC. One type of positive events is leisure, which was also identified as a coping resource. This study extended the DMA and leisure coping research by assessing gender difference in how daily stress severity and leisure time influence AC. Analyzing eight-day diary data, we found that females, compared to males, experienced greater decrease in AC with increase in stress severity but also bigger increase in AC with increase in leisure time. The finding highlights gender difference in affective reactivity to and coping with daily stress, the value of the DMA, and the importance of severity appraisal. PMID:25242824

Analysis of sialyl-Lewis x on MUC5AC and MUC1 mucins in pancreatic cancer tissues.

PubMed

Balmaña, Meritxell; Duran, Adrià; Gomes, Catarina; Llop, Esther; López-Martos, Raquel; Ortiz, M Rosa; Barrabés, Sílvia; Reis, Celso A; Peracaula, Rosa

2018-06-01

Pancreatic adenocarcinoma (PDAC) lacks efficient biomarkers. Mucins are glycoproteins that can carry aberrant glycosylation in cancer. Our objective was to identify cancer-related glycan epitopes on MUC1 and MUC5AC mucins in PDAC as potential biomarkers. We have analysed the tumour-associated carbohydrate antigens sialyl-Lewis x (SLe x ) and sialyl-Tn (STn) on MUC1 and MUC5AC in PDAC tissues. The selected cohort for this study consisted of twenty-one PDAC tissues positive for SLe x antigen and three normal pancreas specimens as controls. STn expression was shown in 76% of the PDAC tissues. MUC1 and MUC5AC were detected in 90% of PDAC tissues. We performed in situ proximity ligation assay combining antibodies against mucins and glycan epitopes to identify specific mucin glycoforms. MUC1-SLe x and MUC5AC-SLe x were found in 68% and 84% respectively, of the mucin expressing PDAC tissues, while STn hardly colocalized with any of the evaluated mucins. Further analysis by Western blot of MUC5AC and SLe x in eight PDAC tissue lysates showed that six out of eight cases were positive for both markers. Moreover, immunoprecipitation of MUC5AC from positive PDAC tissues and subsequent SLe x immunodetection confirmed the presence of SLe x on MUC5AC. Altogether, MUC5AC-SLe x glycoform is present in PDAC and can be regarded as potential biomarker. Copyright © 2018 Elsevier B.V. All rights reserved.

Predominance of the ac variant in K88-positive Escherichia coli isolates from swine.

PubMed Central

Westerman, R B; Mills, K W; Phillips, R M; Fortner, G W; Greenwood, J M

1988-01-01

Monoclonal antibodies to K88ac and K88ab were used in enzyme-linked immunosorbent assays on Escherichia coli cultures known to produce K88 pili. A total of 415 K88-positive E. coli isolates from nine states were all found to be the K88ac variant. The cultures tested were isolated during the years 1976 to 1985. PMID:3277990

AC-driven bilayer graphene: quasienergy spectrum of electrons and generation of soliton-like electromagnetic pulse

NASA Astrophysics Data System (ADS)

Kukhar, Egor I.

2018-01-01

Quasienergy spectrum of electrons in biased bigraphene subjected to the linear polarized high-frequency electromagnetic radiation has been derived. Quasienergy bands of ac-driven bigraphene have been investigated. Dynamical appearing of the saddle points in band structure of biased bigraphene and energy gap modification have been predicted. Electromagnetic field equation has been written using obtained quasienergy spectrum. The solution corresponding to the soliton-like electromagnetic wave has been obtained. The conditions of soliton-like wave generation in ac-driven bigraphene have been discussed.

Instantaneous velocity measurement of AC electroosmotic flows by laser induced fluorescence photobleaching anemometer with high temporal resolution

NASA Astrophysics Data System (ADS)

Zhao, Wei; Yang, Fang; Qiao, Rui; Wang, Guiren; Rui Qiao Collaboration

2015-11-01

Understanding the instantaneous response of flows to applied AC electric fields may help understand some unsolved issues in induced-charge electrokinetics and enhance performance of microfluidic devices. Since currently available velocimeters have difficulty in measuring velocity fluctuations with frequency higher than 1 kHz, most experimental studies so far focus only on the average velocity measurement in AC electrokinetic flows. Here, we present measurements of AC electroosmotic flow (AC-EOF) response time in microchannels by a novel velocimeter with submicrometer spatial resolution and microsecond temporal resolution, i.e. laser-induced fluorescence photobleaching anemometer (LIFPA). Several parameters affecting the AC-EOF response time to the applied electric signal were investigated, i.e. channel length, transverse position and solution conductivity. The experimental results show that the EOF response time under a pulsed electric field decreases with the reduction of the microchannel length, distance between the detection position to the wall and the conductivity of the solution. This work could provide a new powerful tool to measure AC electrokinetics and enhance our understanding of AC electrokinetic flows.

Aeroallergen sensitization predicts acute chest syndrome in children with sickle cell anaemia.

PubMed

Willen, Shaina M; Rodeghier, Mark; Strunk, Robert C; Bacharier, Leonard B; Rosen, Carol L; Kirkham, Fenella J; DeBaun, Michael R; Cohen, Robyn T

2018-02-01

Asthma is associated with higher rates of acute chest syndrome (ACS) and vaso-occlusive pain episodes among children with sickle cell anaemia (SCA). Aeroallergen sensitization is a risk factor for asthma. We hypothesized that aeroallergen sensitization is associated with an increased incidence of hospitalizations for ACS and pain. Participants in a multicentre, longitudinal cohort study, aged 4-18 years with SCA, underwent skin prick testing to ten aeroallergens. ACS and pain episodes were collected from birth until the end of the follow-up period. The number of positive skin tests were tested for associations with prospective rates of ACS and pain. Multivariable models demonstrated additive effects of having positive skin tests on future rates of ACS (incidence rate ratio (IRR) for each positive test 1·23, 95% confidence interval [CI] 1·11-1·36, P < 0·001). Aeroallergen sensitization was not associated with future pain (IRR 1·14, 95%CI 0·97-1·33, P = 0·11). Our study demonstrated that children with SCA and aeroallergen sensitization are at increased risk for future ACS. Future research is needed to determine whether identification of specific sensitizations and allergen avoidance and treatment reduce the risk of ACS for children with SCA. © 2018 John Wiley & Sons Ltd.

Perchlorate adsorption and desorption on activated carbon and anion exchange resin.

PubMed

Yoon, In-Ho; Meng, Xiaoguang; Wang, Chao; Kim, Kyoung-Woong; Bang, Sunbaek; Choe, Eunyoung; Lippincott, Lee

2009-05-15

The mechanisms of perchlorate adsorption on activated carbon (AC) and anion exchange resin (SR-7 resin) were investigated using Raman, FTIR, and zeta potential analyses. Batch adsorption and desorption results demonstrated that the adsorption of perchlorate by AC and SR-7 resin was reversible. The reversibility of perchlorate adsorption by the resin was also proved by column regeneration test. Solution pH significantly affected perchlorate adsorption and the zeta potential of AC, while it did not influence perchlorate adsorption and the zeta potential of resin. Zeta potential measurements showed that perchlorate was adsorbed on the negatively charged AC surface. Raman spectra indicated the adsorption resulted in an obvious position shift of the perchlorate peak, suggesting that perchlorate was associated with functional groups on AC at neutral pH through interactions stronger than electrostatic interaction. The adsorbed perchlorate on the resin exhibited a Raman peak at similar position as the aqueous perchlorate, indicating that perchlorate was adsorbed on the resin through electrostatic attraction between the anion and positively charged surface sites.

Academic context and perceived mental workload of psychology students.

PubMed

Rubio-Valdehita, Susana; López-Higes, Ramón; Díaz-Ramiro, Eva

2014-01-01

The excessive workload of university students is an academic stressor. Consequently, it is necessary to evaluate and control the workload in education. This research applies the NASA-TLX scale, as a measure of the workload. The objectives of this study were: (a) to measure the workload levels of a sample of 367 psychology students, (b) to group students according to their positive or negative perception of academic context (AC) and c) to analyze the effects of AC on workload. To assess the perceived AC, we used an ad hoc questionnaire designed according to Demand-Control-Social Support and Effort-Reward Imbalance models. Using cluster analysis, participants were classified into two groups (positive versus negative context). The differences between groups show that a positive AC improves performance (p < .01) and reduces feelings of overload (p < .02), temporal demand (p < .02), and nervousness and frustration (p < .001). Social relationships with peers and teachers, student autonomy and result satisfaction were relevant dimensions of the AC (p < .001 in all cases).

The effects of optimism and gratitude on adherence, functioning and mental health following an acute coronary syndrome.

PubMed

Millstein, Rachel A; Celano, Christopher M; Beale, Eleanor E; Beach, Scott R; Suarez, Laura; Belcher, Arianna M; Januzzi, James L; Huffman, Jeff C

This study examined the effects of optimism and gratitude on self-reported health behavior adherence, physical functioning and emotional well-being after an acute coronary syndrome (ACS). Among 156 patients, we examined associations between optimism and gratitude measured 2 weeks post-ACS and 6-month outcomes: adherence to medical recommendations, mental and physical health-related quality of life (HRQoL), physical functioning, depressive symptoms and anxiety. Multivariable linear regression models were used, controlling for increasing levels of adjustment. Optimism [β=.11, standard error (S.E.)=.05, P=.038] and gratitude (β=.10, S.E.=.05, P=.027) at 2 weeks were associated with subsequent self-reported adherence to medical recommendations (diet, exercise, medication adherence, stress reduction) at 6 months in fully adjusted models. Two-week optimism and gratitude were associated with improvements in mental HRQoL (optimism: β=.44, S.E.=.13, P=.001; gratitude: β=.33, S.E.=.12, P=.005) and reductions in symptoms of depression (optimism: β=-.11, S.E.=.05, P=.039; gratitude: β=-.10, S.E.=.05, P=.028) and anxiety (optimism: β=-.15, S.E.=.05, P=.004; gratitude: β=-.10, S.E.=.05, P=.034) at 6 months. Optimism and gratitude at 2 weeks post-ACS were associated with higher self-reported adherence and improved emotional well-being 6 months later, independent of negative emotional states. Optimism and gratitude may help recovery from an ACS. Interventions promoting these positive constructs could help improve adherence and well-being. Copyright © 2016 Elsevier Inc. All rights reserved.

Astrometric Measurements of Triple Star System 15379+3006 STF 1963AB, STF 1963AC

NASA Astrophysics Data System (ADS)

Russell, Harker; Miller, Lindsey; Beltzer-Sweeney, Alexander; Shilts, Trey; Stojimirovic, Irena

2018-04-01

Research team PRSM reports astrometric measurements of the double star system WDS 15379+3006 (STF 1963AB, STF 1963AC) obtained using the iTelescope Network. By performing CCD astrometry, the team determined a position angle of 298.4° ± 0.1° with an angular separation of 05. 28" ± 0.1" for STF 1963AB, and a position angle of 116.1° ± 0.1° with an angular separation of 32.35" ± 0.1" for STF 1963AC. The angular separation and position angle have changed from previous measurements.

A new infusion pathway intactness monitoring system.

PubMed

Ogawa, Hidekuni; Yonezawa, Yoshiharu; Maki, Hiromichi; Ninomiya, Ishio; Sata, Koji; Hamada, Shingo; Caldwell, W Morton

2006-01-01

A new infusion pathway monitoring system has been developed for hospital and home use. The system consists of linear integrated circuits and a low-power 8-bit single chip microcomputer which constantly monitors the infusion pathway intactness. An AC (alternating current) voltage is induced on the patient's body by electrostatic coupling from the normal 100 volt, 60 Hz AC power line wiring field in the patient's room. The induced AC voltage can be recorded by a main electrode wrapped around the infusion polyvinyl chloride tube. A reference electrode is wrapped on the electrode to monitor the AC voltage around the main electrode. If the injection needle or infusion tube becomes detached, then the system detects changes in the induced AC voltages and alerts the nursing station, via the nurse call system or PHS (personal handy phone system).

Dynamic Correlations between Intrinsic Connectivity and Extrinsic Connectivity of the Auditory Cortex in Humans.

PubMed

Cui, Zhuang; Wang, Qian; Gao, Yayue; Wang, Jing; Wang, Mengyang; Teng, Pengfei; Guan, Yuguang; Zhou, Jian; Li, Tianfu; Luan, Guoming; Li, Liang

2017-01-01

The arrival of sound signals in the auditory cortex (AC) triggers both local and inter-regional signal propagations over time up to hundreds of milliseconds and builds up both intrinsic functional connectivity (iFC) and extrinsic functional connectivity (eFC) of the AC. However, interactions between iFC and eFC are largely unknown. Using intracranial stereo-electroencephalographic recordings in people with drug-refractory epilepsy, this study mainly investigated the temporal dynamic of the relationships between iFC and eFC of the AC. The results showed that a Gaussian wideband-noise burst markedly elicited potentials in both the AC and numerous higher-order cortical regions outside the AC (non-auditory cortices). Granger causality analyses revealed that in the earlier time window, iFC of the AC was positively correlated with both eFC from the AC to the inferior temporal gyrus and that to the inferior parietal lobule. While in later periods, the iFC of the AC was positively correlated with eFC from the precentral gyrus to the AC and that from the insula to the AC. In conclusion, dual-directional interactions occur between iFC and eFC of the AC at different time windows following the sound stimulation and may form the foundation underlying various central auditory processes, including auditory sensory memory, object formation, integrations between sensory, perceptional, attentional, motor, emotional, and executive processes.

Precursor and Neutral Loss Scans in an RF Scanning Linear Quadrupole Ion Trap

NASA Astrophysics Data System (ADS)

Snyder, Dalton T.; Szalwinski, Lucas J.; Schrader, Robert L.; Pirro, Valentina; Hilger, Ryan; Cooks, R. Graham

2018-03-01

Methodology for performing precursor and neutral loss scans in an RF scanning linear quadrupole ion trap is described and compared to the unconventional ac frequency scan technique. In the RF scanning variant, precursor ions are mass selectively excited by a fixed frequency resonance excitation signal at low Mathieu q while the RF amplitude is ramped linearly to pass ions through the point of excitation such that the excited ion's m/z varies linearly with time. Ironically, a nonlinear ac frequency scan is still required for ejection of the product ions since their frequencies vary nonlinearly with the linearly varying RF amplitude. In the case of the precursor scan, the ejection frequency must be scanned so that it is fixed on a product ion m/z throughout the RF scan, whereas in the neutral loss scan, it must be scanned to maintain a constant mass offset from the excited precursor ions. Both simultaneous and sequential permutation scans are possible; only the former are demonstrated here. The scans described are performed on a variety of samples using different ionization sources: protonated amphetamine ions generated by nanoelectrospray ionization (nESI), explosives ionized by low-temperature plasma (LTP), and chemical warfare agent simulants sampled from a surface and analyzed with swab touch spray (TS). We lastly conclude that the ac frequency scan variant of these MS/MS scans is preferred due to electronic simplicity. In an accompanying manuscript, we thus describe the implementation of orthogonal double resonance precursor and neutral loss scans on the Mini 12 using constant RF voltage. [Figure not available: see fulltext.

The KAC family of kinesin-like proteins is essential for the association of chloroplasts with the plasma membrane in land plants.

PubMed

Suetsugu, Noriyuki; Sato, Yoshikatsu; Tsuboi, Hidenori; Kasahara, Masahiro; Imaizumi, Takato; Kagawa, Takatoshi; Hiwatashi, Yuji; Hasebe, Mitsuyasu; Wada, Masamitsu

2012-11-01

Chloroplasts require association with the plasma membrane for movement in response to light and for appropriate positioning within the cell to capture photosynthetic light efficiently. In Arabidopsis, CHLOROPLAST UNUSUAL POSITIONING 1 (CHUP1), KINESIN-LIKE PROTEIN FOR ACTIN-BASED CHLOROPLAST MOVEMENT 1 (KAC1) and KAC2 are required for both the proper movement of chloroplasts and the association of chloroplasts with the plasma membrane, through the reorganization of short actin filaments located on the periphery of the chloroplasts. Here, we show that KAC and CHUP1 orthologs (AcKAC1, AcCHUP1A and AcCHUP1B, and PpKAC1 and PpKAC2) play important roles in chloroplast positioning in the fern Adiantum capillus-veneris and the moss Physcomitrella patens. The knockdown of AcKAC1 and two AcCHUP1 genes induced the aggregation of chloroplasts around the nucleus. Analyses of A. capillus-veneris mutants containing perinuclear-aggregated chloroplasts confirmed that AcKAC1 is required for chloroplast-plasma membrane association. In addition, P. patens lines in which two KAC genes had been knocked out showed an aggregated chloroplast phenotype similar to that of the fern kac1 mutants. These results indicate that chloroplast positioning and movement are mediated through the activities of KAC and CHUP1 proteins, which are conserved in land plants.

Production of Ac-225 for cancer therapy by photon-induced transmutation of Ra-226.

PubMed

Melville, G; Meriarty, H; Metcalfe, P; Knittel, T; Allen, B J

2007-09-01

The increasing application of Ac-225 for cancer therapy indicates the potential need for its increased production and availability. The production of Ac-225 has been achieved using bremsstrahlung photons from an 18 MV medical linear accelerator (linac) to bombard a Ra-226 target. A linac dose of 2800 Gy produced about 64 microCi of Ra-225, which decays to Ac-225. This result, while consistent with the theoretical calculations, is far too low to be of practical use. A more powerful linac is required that runs at a higher current, longer pulse length and higher frequency for practical production. This process could also lead to the reduction of the nuclear waste product Ra-226.

Grain sorghum is a viable feedstock for ethanol production.

PubMed

Wang, D; Bean, S; McLaren, J; Seib, P; Madl, R; Tuinstra, M; Shi, Y; Lenz, M; Wu, X; Zhao, R

2008-05-01

Sorghum is a major cereal crop in the USA. However, sorghum has been underutilized as a renewable feedstock for bioenergy. The goal of this research was to improve the bioconversion efficiency for biofuels and biobased products from processed sorghum. The main focus was to understand the relationship among "genetics-structure-function-conversion" and the key factors impacting ethanol production, as well as to develop an energy life cycle analysis model (ELCAM) to quantify and prioritize the saving potential from factors identified in this research. Genetic lines with extremely high and low ethanol fermentation efficiency and some specific attributes that may be manipulated to improve the bioconversion rate of sorghum were identified. In general, ethanol yield increased as starch content increased. However, no linear relationship between starch content and fermentation efficiency was found. Key factors affecting the ethanol fermentation efficiency of sorghum include protein digestibility, level of extractable proteins, protein and starch interaction, mash viscosity, amount of phenolic compounds, ratio of amylose to amylopectin, and formation of amylose-lipid complexes in the mash. A platform ELCAM with a base case showed a positive net energy value (NEV) = 25,500 Btu/gal EtOH. ELCAM cases were used to identify factors that most impact sorghum use. For example, a yield increase of 40 bu/ac resulted in NEV increasing from 7 million to 12 million Btu/ac. An 8% increase in starch provided an incremental 1.2 million Btu/ac.

Discovery and characterization of sialic acid O-acetylation in group B Streptococcus.

PubMed

Lewis, Amanda L; Nizet, Victor; Varki, Ajit

2004-07-27

Group B Streptococcus (GBS) is the leading cause of human neonatal sepsis and meningitis. The GBS capsular polysaccharide is a major virulence factor and the active principle of vaccines in phase II trials. All GBS capsules have a terminal alpha 2-3-linked sialic acid [N-acetylneuraminic acid (Neu5Ac)], which interferes with complement-mediated killing. We show here that some of the Neu5Ac residues of the GBS type III capsule are O-acetylated at carbon position 7, 8, or 9, a major modification evidently missed in previous studies. Data are consistent with initial O-acetylation at position 7, and subsequent migration of the O-acetyl ester at positions 8 and 9. O-acetylation was also present on several other GBS serotypes (Ia, Ib, II, V, and VI). Deletion of the CMP-Neu5Ac synthase gene neuA by precise, in-frame allelic replacement gave intracellular accumulation of O-acetylated Neu5Ac, whereas overexpression markedly decreased O-acetylation. Given the known GBS Neu5Ac biosynthesis pathway, these data indicate that O-acetylation occurs on free Neu5Ac, competing with the CMP-Neu5Ac synthase. O-acetylation often generates immunogenic epitopes on bacterial capsular polysaccharides and can modulate human alternate pathway complement activation. Thus, our discovery has important implications for GBS pathogenicity, immunogenicity, and vaccine design.

Nonlinear dynamics of a magnetically driven Duffing-type spring-magnet oscillator in the static magnetic field of a coil

NASA Astrophysics Data System (ADS)

Donoso, Guillermo; Ladera, Celso L.

2012-11-01

We study the nonlinear oscillations of a forced and weakly dissipative spring-magnet system moving in the magnetic fields of two fixed coaxial, hollow induction coils. As the first coil is excited with a dc current, both a linear and a cubic magnet-position dependent force appear on the magnet-spring system. The second coil, located below the first, excited with an ac current, provides the oscillating magnetic driving force on the system. From the magnet-coil interactions, we obtain, analytically, the nonlinear motion equation of the system, found to be a forced and damped cubic Duffing oscillator moving in a quartic potential. The relative strengths of the coefficients of the motion equation can be easily set by varying the coils’ dc and ac currents. We demonstrate, theoretically and experimentally, the nonlinear behaviour of this oscillator, including its oscillation modes and nonlinear resonances, the fold-over effect, the hysteresis and amplitude jumps, and its chaotic behaviour. It is an oscillating system suitable for teaching an advanced experiment in nonlinear dynamics both at senior undergraduate and graduate levels.

Contributions of Mirror and Ion Bernstein Instabilities to the Scattering of Pickup Ions in the Outer Heliosheath

NASA Astrophysics Data System (ADS)

Min, Kyungguk; Liu, Kaijun

2018-01-01

Maintaining the stability of pickup ions in the outer heliosheath is a critical element for the secondary energetic neutral atom (ENA) mechanism, a theory put forth to explain the nearly annular band of ENA emission observed by the Interstellar Boundary EXplorer. A recent study showed that a pickup ion ring can remain stable to the Alfvén/ion cyclotron (AC) instability at propagation parallel to the background magnetic field when the parallel thermal spread of the ring is comparable to that of a background population. This study investigates the potential role that the mirror or ion Bernstein (IB) instabilities can play in the stability of pickup ions when conditions are such that the AC instability is suppressed. Linear Vlasov theory predicts relatively fast mirror and IB instability growth even though AC instability growth is suppressed. For a few such cases, two-dimensional hybrid and macroscopic quasi-linear simulations are carried out to examine how the unstable mirror and IB modes evolve and affect the pickup ion ring beyond the linear theory picture. For the parameters used, the mirror mode dominates initially and leads to a rapid parallel heating of the pickup ions in excess of the parallel temperature of the background protons. The heated pickup ions subsequently trigger onset of the AC mode, which grows sufficiently large to be the dominant pitch angle scattering agent after the mirror mode has decayed away. The present results indicate that the pickup ion stability needed may not be guaranteed once the mirror and IB instabilities are taken into account.

Imitative modeling automatic system Control of steam pressure in the main steam collector with the influence on the main Servomotor steam turbine

NASA Astrophysics Data System (ADS)

Andriushin, A. V.; Zverkov, V. P.; Kuzishchin, V. F.; Ryzhkov, O. S.; Sabanin, V. R.

2017-11-01

The research and setting results of steam pressure in the main steam collector “Do itself” automatic control system (ACS) with high-speed feedback on steam pressure in the turbine regulating stage are presented. The ACS setup is performed on the simulation model of the controlled object developed for this purpose with load-dependent static and dynamic characteristics and a non-linear control algorithm with pulse control of the turbine main servomotor. A method for tuning nonlinear ACS with a numerical algorithm for multiparametric optimization and a procedure for separate dynamic adjustment of control devices in a two-loop ACS are proposed and implemented. It is shown that the nonlinear ACS adjusted with the proposed method with the regulators constant parameters ensures reliable and high-quality operation without the occurrence of oscillations in the transient processes the operating range of the turbine loads.

Electrical transport in lead-free (Na0.5Bi0.5)1-xSrxTiO3 ceramics (x = 0, 0.01 and 0.02)

NASA Astrophysics Data System (ADS)

Dutkiewicz, E. M.; Suchanicz, J.; Konieczny, K.; Czaja, P.; Kluczewska, K.; Czternastek, H.; Antonova, M.; Sternberg, A.

2017-09-01

Lead-free (Na0.5Bi0.5)1xSrxTiO3 (x = 0, 0.01 and 0.02) ceramics were manufactured through a solid-state mixed oxide method and their ac (σac) and dc (σdc) electric conductivity were studied. It is shown that the low-frequency (100 Hz-1 MHz) ac conductivity obeys a power law σac ∼ ωs characteristic for disordered materials. Both the dc and ac conductivities have thermally activated character and possess linear parts with different activation energies. The calculated activation energies are attributed to different mechanism of conductivity. Frequency dependence of σdc and exponent s is reasonably interpreted by a correlated barrier hopping model. The NBT-ST system is expected to be a new promising candidate for lead-free electronic materials.

AC magnetic field measurement using a small flip coil system for rapid cycling AC magnets at the China Spallation Neutron Source (CSNS)

NASA Astrophysics Data System (ADS)

Zhou, Jianxin; Kang, Wen; Li, Shuai; Liu, Yudong; Liu, Yiqin; Xu, Shouyan; Guo, Xiaoling; Wu, Xi; Deng, Changdong; Li, Li; Wu, Yuwen; Wang, Sheng

2018-02-01

The China Spallation Neutron Source (CSNS) has two major accelerator systems, a linear accelerator and a rapid cycling synchrotron (RCS). The RCS accelerator is used to accumulate and accelerate protons from the energy of 80 MeV to the design energy of 1.6 GeV at the repetition rate of 25 Hz, and extract the high energy beam to the target. The main magnets of the RCS accelerator are excited by AC current with DC bias. The magnetic field quality is very important for the RCS accelerator operation, since it should guarantee and focus a circulating beam. In order to characterize the AC magnets, a small flip coil measurement system has been developed and one of each type of AC magnets has been studied. The measurement system and selected measurement results are presented in this paper.

Chance-Constrained AC Optimal Power Flow for Distribution Systems With Renewables

DOE Office of Scientific and Technical Information (OSTI.GOV)

DallAnese, Emiliano; Baker, Kyri; Summers, Tyler

This paper focuses on distribution systems featuring renewable energy sources (RESs) and energy storage systems, and presents an AC optimal power flow (OPF) approach to optimize system-level performance objectives while coping with uncertainty in both RES generation and loads. The proposed method hinges on a chance-constrained AC OPF formulation where probabilistic constraints are utilized to enforce voltage regulation with prescribed probability. A computationally more affordable convex reformulation is developed by resorting to suitable linear approximations of the AC power-flow equations as well as convex approximations of the chance constraints. The approximate chance constraints provide conservative bounds that hold for arbitrarymore » distributions of the forecasting errors. An adaptive strategy is then obtained by embedding the proposed AC OPF task into a model predictive control framework. Finally, a distributed solver is developed to strategically distribute the solution of the optimization problems across utility and customers.« less

Preparation and chromatographic evaluation of zwitterionic stationary phases with controllable ratio of positively and negatively charged groups.

PubMed

Cheng, Xiao-Dong; Hao, Yan-Hong; Peng, Xi-Tian; Yuan, Bi-Feng; Shi, Zhi-Guo; Feng, Yu-Qi

2015-08-15

The present study described the preparation and application of zwitterionic stationary phases (ACS) with controllable ratio of positively charged tertiary amine groups and negatively charged carboxyl groups. Various parameters, including water content, pH values and ionic strength of the mobile phase, were investigated to study the chromatographic characteristics of ACS columns. The prepared ACS columns demonstrated a mix-mode retention mechanism composed of surface adsorption, partitioning and electrostatic interactions. The elemental analysis of different batches of the ACS phases demonstrated good reproducibility of the preparation strategy. Additionally, various categories of compounds, including nucleosides, water-soluble vitamins, benzoic acid derivatives and basic compounds were successively employed to evaluate the separation selectivity of the prepared ACS stationary phases. These ACS phases exhibited entirely different selectivity and retention behavior from each other for various polar analytes, demonstrating the excellent application potential in the analysis of polar compounds in HILIC. Copyright © 2015 Elsevier B.V. All rights reserved.

Single Phase Passive Rectification Versus Active Rectification Applied to High Power Stirling Engines

NASA Technical Reports Server (NTRS)

Santiago, Walter; Birchenough, Arthur G.

2006-01-01

Stirling engine converters are being considered as potential candidates for high power energy conversion systems required by future NASA explorations missions. These types of engines typically contain two major moving parts, the displacer and the piston, in which a linear alternator is attached to the piston to produce a single phase sinusoidal waveform at a specific electric frequency. Since all Stirling engines perform at low electrical frequencies (less or equal to 100 Hz), space explorations missions that will employ these engines will be required to use DC power management and distribution (PMAD) system instead of an AC PMAD system to save on space and weight. Therefore, to supply such DC power an AC to DC converter is connected to the Stirling engine. There are two types of AC to DC converters that can be employed, a passive full bridge diode rectifier and an active switching full bridge rectifier. Due to the inherent line inductance of the Stirling Engine-Linear Alternator (SE-LA), their sinusoidal voltage and current will be phase shifted producing a power factor below 1. In order to keep power the factor close to unity, both AC to DC converters topologies will implement power factor correction. This paper discusses these power factor correction methods as well as their impact on overall mass for exploration applications. Simulation results on both AC to DC converters topologies with power factor correction as a function of output power and SE-LA line inductance impedance are presented and compared.

Quantifying interactions between accommodation and vergence in a binocularly normal population.

PubMed

Sweeney, Laura E; Seidel, Dirk; Day, Mhairi; Gray, Lyle S

2014-12-01

Stimulation of the accommodation system results in a response in the vergence system via accommodative vergence cross-link interactions, and stimulation of the vergence system results in an accommodation response via vergence accommodation cross-link interactions. Cross-link interactions are necessary in order to ensure simultaneous responses in the accommodation and vergence systems. The crosslink interactions are represented most comprehensively by the response AC/A (accommodative vergence) and CA/C (vergence accommodation) ratios, although the stimulus AC/A ratio is measured clinically, and the stimulus CA/C ratio is seldom measured in clinical practice. The present study aims to quantify both stimulus and response AC/A and CA/C ratios in a binocularly normal population, and determine the relationship between them. 25 Subjects (mean ± SD age 21.0 ± 1.9 years) were recruited from the university population. A significant linear relationship was found between the stimulus and response ratios, for both AC/A (r² = 0.96, p < 0.001) and CA/C ratios (r² = 0.40, p < 0.05). Good agreement was found between the stimulus and response AC/A ratios (95% CI -0.06 to 0.24 MA/D). Stimulus and response CA/C ratios are linearly related. Stimulus CA/C ratios were higher than response ratios at low values, and lower than response ratios at high values (95% CI -0.46 to 0.42 D/MA). Agreement between stimulus and response CA/C ratios is poorer than that found for AC/A ratios due to increased variability in vergence responses when viewing the Gaussian blurred target. This study has shown that more work is needed to refine the methodology of CA/C ratio measurement.

Value of a Dixon-based MR/PET attenuation correction sequence for the localization and evaluation of PET-positive lesions.

PubMed

Eiber, Matthias; Martinez-Möller, Axel; Souvatzoglou, Michael; Holzapfel, Konstantin; Pickhard, Anja; Löffelbein, Dennys; Santi, Ivan; Rummeny, Ernst J; Ziegler, Sibylle; Schwaiger, Markus; Nekolla, Stephan G; Beer, Ambros J

2011-09-01

In this study, the potential contribution of Dixon-based MR imaging with a rapid low-resolution breath-hold sequence, which is a technique used for MR-based attenuation correction (AC) for MR/positron emission tomography (PET), was evaluated for anatomical correlation of PET-positive lesions on a 3T clinical scanner compared to low-dose CT. This technique is also used in a recently installed fully integrated whole-body MR/PET system. Thirty-five patients routinely scheduled for oncological staging underwent (18)F-fluorodeoxyglucose (FDG) PET/CT and a 2-point Dixon 3-D volumetric interpolated breath-hold examination (VIBE) T1-weighted MR sequence on the same day. Two PET data sets reconstructed using attenuation maps from low-dose CT (PET(AC_CT)) or simulated MR-based segmentation (PET(AC_MR)) were evaluated for focal PET-positive lesions. The certainty for the correlation with anatomical structures was judged in the low-dose CT and Dixon-based MRI on a 4-point scale (0-3). In addition, the standardized uptake values (SUVs) for PET(AC_CT) and PET(AC_MR) were compared. Statistically, no significant difference could be found concerning anatomical localization for all 81 PET-positive lesions in low-dose CT compared to Dixon-based MR (mean 2.51 ± 0.85 and 2.37 ± 0.87, respectively; p = 0.1909). CT tended to be superior for small lymph nodes, bone metastases and pulmonary nodules, while Dixon-based MR proved advantageous for soft tissue pathologies like head/neck tumours and liver metastases. For the PET(AC_CT)- and PET(AC_MR)-based SUVs (mean 6.36 ± 4.47 and 6.31 ± 4.52, respectively) a nearly complete concordance with a highly significant correlation was found (r = 0.9975, p < 0.0001). Dixon-based MR imaging for MR AC allows for anatomical allocation of PET-positive lesions similar to low-dose CT in conventional PET/CT. Thus, this approach appears to be useful for future MR/PET for body regions not fully covered by diagnostic MRI due to potential time constraints.

A solid-state controllable power supply for a magnetic suspension wind tunnel

NASA Technical Reports Server (NTRS)

Daniels, Taumi S.; Tripp, John S.

1991-01-01

The NASA Langley 6-inch Magnetic Suspension and Balance System (6-in. MSBS) requires an independently controlled bidirectional dc power source for each of six positioning electromagnets. These electromagnets provide five-degree-of-freedom control over a suspended aerodynamic test model. Existing power equipment, which employs resistance-coupled thyratron-controlled rectifiers as well as ac to dc motor-generator converters, is obsolete, inefficient, and unreliable. A replacement six-phase bidirectional controlled bridge rectifier is proposed, which employs power MOSFET switches sequenced by hybrid analog/digital circuits. Full-load efficiency is 80 percent compared with 25 percent for the resistance-coupled thyratron system. Current feedback provides high control linearity, adjustable current limiting, and current overload protection. A quenching circuit suppresses inductive voltage impulses. It is shown that 20-kHz interference from positioning magnet power into MSBS electromagnetic model position sensors results predominantly from capacitively coupled electric fields. Hence, proper shielding and grounding techniques are necessary. Inductively coupled magnetic interference is negligible.

Here Be Dragons: Characterization of ACS/WFC Scattered Light Anomalies

NASA Astrophysics Data System (ADS)

Porterfield, B.; Coe, D.; Gonzaga, S.; Anderson, J.; Grogin, N.

2016-11-01

We present a study characterizing scattered light anomalies that occur near the edges of Advanced Camera for Surveys (ACS) Wide Field Channel (WFC) images. We inspected all 8,573 full-frame ACS/WFC raw images with exposure times longer than 350 seconds obtained in the F606W and F814W filters from 2002 to October 2013. We visually identified two particular scattered light artifacts known as "dragon's breath" and edge glow. Using the 2MASS point source catalog and Hubble Guide Star Catalog (GSC II), we identified the stars that caused these artifacts. The stars are all located in narrow bands ( 3" across) just outside the ACS/WFC field of view (2" - 16" away). We provide a map of these risky areas around the ACS/WFC detectors - users should avoid positioning bright stars in these regions when designing ACS/WFC imaging observations. We also provide interactive webpages which display all the image artifacts we identified, allowing users to see examples of the severity of artifacts they might expect for a given stellar magnitude at a given position relative to the ACS/WFC field of view. On average, 10th (18th) magnitude stars produce artifacts about 1,000 (100) pixels long. But the severity of these artifacts can vary strongly with small positional shifts (∼ 1"). The results are similar for both filters (F606W and F814W) when expressed in total fluence, or flux multiplied by exposure time.

Electronic spectra and excited-state dynamics of acridine and its hydrated clusters

NASA Astrophysics Data System (ADS)

Harthcock, Colin; Zhang, Jie; Kong, Wei; Mitsui, Masaaki; Ohshima, Yasuhiro

2017-04-01

We combine results from several different experiments to investigate the photophysics of acridine (Ac) and its hydrated clusters in the gas phase. Our findings are also compared with results from condensed phase studies. Similar to measurements of Ac dissolved in hydrocarbons, the lifetime of the first electronically excited state of isolated Ac in vacuum is too short for typical resonantly enhanced multiphoton ionization (REMPI) and laser induced fluorescence (LIF) experiments, hence no signal from REMPI and LIF can be attributed to monomeric Ac. Instead, sensitized phosphorescence emission spectroscopy is more successful in revealing the electronic states of Ac. Upon clustering with water, on the other hand, the lifetimes of the excited states are substantially increased to the nanosecond scale, and with two water molecules attached to Ac, the lifetime of the hydrated cluster is essentially the same as that of Ac in aqueous solutions. Detailed REMPI and ultraviolet-ultraviolet hole-burning experiments are then performed to reveal the structural information of the hydrated clusters. Although the formation of hydrogen bonds results in energy level reversal and energy separation between the first two excited states of Ac, its effect on the internal geometry of Ac is minimal, and all clusters with 1-3 water molecules demonstrate consistent intramolecular vibrational modes. Theoretical calculations reveal just one stable structure for each cluster under supersonic molecular beam conditions. Furthermore, different from mono- and di-water clusters, tri-water clusters consist of a linear chain of three water molecules attached to Ac. Consequently, the fragmentation pattern in the REMPI spectrum of tri-water clusters seems to be dominated by water trimer elimination, since the REMPI spectrum of Ac+.W3 is largely reproduced in the Ac+ mass channel, but not in the Ac+.W1 or Ac+.W2 channel.

Off-resonance energy absorption in a linear Paul trap due to mass selective resonant quenching

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sivarajah, I.; Goodman, D. S.; Wells, J. E.

Linear Paul traps (LPT) are used in many experimental studies such as mass spectrometry, atom-ion collisions, and ion-molecule reactions. Mass selective resonant quenching (MSRQ) is implemented in LPT either to identify a charged particle's mass or to remove unwanted ions from a controlled experimental environment. In the latter case, MSRQ can introduce undesired heating to co-trapped ions of different mass, whose secular motion is off resonance with the quenching ac field, which we call off-resonance energy absorption (OREA). We present simulations and experimental evidence that show that the OREA increases exponentially with the number of ions loaded into the trapmore » and with the amplitude of the off-resonance external ac field.« less

Linearity of the Faraday-rotation-type ac magnetic-field sensor with a ferrimagnetic or ferromagnetic rotator film

NASA Astrophysics Data System (ADS)

Mori, Hiroshi; Asahara, Yousuke

1996-03-01

We analyze the linearity and modulation depth of ac magnetic-field sensors or current sensors, using a ferrimagnetic or ferromagnetic film as the Faraday rotator and employing the detection of only the zeroth-order optical diffraction component from the rotator. It is theoretically shown that for this class of sensor the condition of a constant modulation depth and that of a constant ratio error give an identical series of curves for the relationship between Faraday rotation angle greater than or equals V and polarizer/analyzer relative angle Phi . We give some numerical examples to demonstrate the usefulness of the result with reference to a rare-earth iron garnet film as the rotator.

Dynamic magnetic hysteresis and nonlinear susceptibility of antiferromagnetic nanoparticles

NASA Astrophysics Data System (ADS)

Kalmykov, Yuri P.; Ouari, Bachir; Titov, Serguey V.

2016-08-01

The nonlinear ac stationary response of antiferromagnetic nanoparticles subjected to both external ac and dc fields of arbitrary strength and orientation is investigated using Brown's continuous diffusion model. The nonlinear complex susceptibility and dynamic magnetic hysteresis (DMH) loops of an individual antiferromagnetic nanoparticle are evaluated and compared with the linear regime for extensive ranges of the anisotropy, the ac and dc magnetic fields, damping, and the specific antiferromagnetic parameter. It is shown that the shape and area of the DMH loops of antiferromagnetic particles are substantially altered by applying a dc field that permits tuning of the specific magnetic power loss in the nanoparticles.

The protein phosphatase 2A catalytic subunit StPP2Ac2b acts as a positive regulator of tuberization induction in Solanum tuberosum L.

PubMed

Muñiz García, María Noelia; Muro, María Catalina; Mazzocchi, Luciana Carla; País, Silvia Marina; Stritzler, Margarita; Schlesinger, Mariana; Capiati, Daniela Andrea

2017-02-01

This study provides the first genetic evidence for the role of PP2A in tuberization, demonstrating that the catalytic subunit StPP2Ac2b positively modulates tuber induction, and that its function is related to the regulation of gibberellic acid metabolism. The results contribute to a better understanding of the molecular mechanism controlling tuberization induction, which remains largely unknown. The serine/threonine protein phosphatases type 2A (PP2A) are implicated in several physiological processes in plants, playing important roles in hormone responses. In cultivated potato (Solanum tuberosum), six PP2A catalytic subunits (StPP2Ac) were identified. The PP2Ac of the subfamily I (StPP2Ac1, 2a and 2b) were suggested to be involved in the tuberization signaling in leaves, where the environmental and hormonal signals are perceived and integrated. The aim of this study was to investigate the role of PP2A in the tuberization induction in stolons. We selected one of the catalytic subunits of the subfamily I, StPP2Ac2b, to develop transgenic plants overexpressing this gene (StPP2Ac2b-OE). Stolons from StPP2Ac2b-OE plants show higher tuber induction rates in vitro, as compared to wild type stolons, with no differences in the number of tubers obtained at the end of the process. This effect is accompanied by higher expression levels of the gibberellic acid (GA) catabolic enzyme StGA2ox1. GA up-regulates StPP2Ac2b expression in stolons, possibly as part of the feedback system by which the hormone regulates its own level. Sucrose, a tuber-promoting factor in vitro, increases StPP2Ac2b expression. We conclude that StPP2Ac2b acts in stolons as a positive regulator tuber induction, integrating different tuberization-related signals mainly though the modulation of GA metabolism.

Possible increase in insulin resistance and concealed glucose-coupled potassium-lowering mechanisms during acute coronary syndrome documented by covariance structure analysis.

PubMed

Ito, Satoshi; Nagoshi, Tomohisa; Minai, Kosuke; Kashiwagi, Yusuke; Sekiyama, Hiroshi; Yoshii, Akira; Kimura, Haruka; Inoue, Yasunori; Ogawa, Kazuo; Tanaka, Toshikazu D; Ogawa, Takayuki; Kawai, Makoto; Yoshimura, Michihiro

2017-01-01

Although glucose-insulin-potassium (GIK) therapy ought to be beneficial for ischemic heart disease in general, variable outcomes in many clinical trials of GIK in acute coronary syndrome (ACS) had a controversial impact. This study was designed to examine whether "insulin resistance" is involved in ACS and to clarify other potential intrinsic compensatory mechanisms for GIK tolerance through highly statistical procedure. We compared the degree of insulin resistance during ACS attack and remission phase after treatment in individual patients (n = 104). During ACS, homeostasis model assessment of insulin resistance (HOMA-IR) values were significantly increased (P<0.001), while serum potassium levels were transiently decreased (degree of which was indicated by ΔK) (P<0.001). This finding provides a renewed paradox, as ΔK, a surrogate marker of intrinsic GIK cascade activation, probably reflects the validated glucose metabolism during ischemic attack. Indeed, multiple regression analysis revealed that plasma glucose level during ACS was positively correlated with ΔK (P = 0.026), whereas HOMA-IR had no impact on ΔK. This positive correlation between ΔK and glucose was confirmed by covariance structure analysis with a strong impact (β: 0.398, P = 0.015). Intriguingly, a higher incidence of myocardial infarction relative to unstable angina pectoris, as well as a longer hospitalization period were observed in patients with larger ΔK, indicating that ΔK also reflects disease severity of ACS. Insulin resistance most likely increases during ACS; however, ΔK was positively correlated with plasma glucose level, which overwhelmed insulin resistance condition. The present study with covariance structure analysis suggests that there are potential endogenous glucose-coupled potassium lowering mechanisms, other than insulin, regulating glucose metabolism during ACS.

Anticholinergic Drug Use and Risk of Cognitive Performance in Older Adults with Questionable Cognitive Impairment: A Cross-Sectional Analysis

PubMed Central

Swami, Sunil; Cohen, Ronald A.; Kairalla, John A.; Manini, Todd M.

2018-01-01

Background Age-associated decline in central cholinergic activity makes older adults susceptible to harmful effects of anticholinergic (AC) medications. However, there is an inadequate understanding of association and possible effects of AC drugs on cognition. This cross-sectional study examines the associations of AC medications on cognition among older adults with questionable cognitive impairment (QCI). Methods For this cross-sectional study, we used multicenter database of community dwelling older adults (N=7,351) aged 60+ years with QCI from September 2005 until March 2014 as baseline data. Anticholinergic Drug Scale was used to categorize AC drug load in no, low or moderate/high groups. Individuals with clinical dementia rating-sum of boxes score between 0.5 and 2.5 were identify as having QCI. Cognitive performance was evaluated using Neuropsychological Test Battery. The mean z-scores of neuropsychological tests were grouped into a global cognition score. Results Participants who took AC medications were older, largely female and had higher prevalence of incontinence than those without AC exposure. Global cognition was significantly greater in moderate/high AC group than no AC group (-0.23±0.53 vs. -0.32±0.53). Multivariable linear regression showed that global cognition score among low and moderate/high AC groups, as compared to no AC group, was higher by 0.064 (P=.006 and P=.12, respectively). Conclusions This cross-sectional study indicates that older adults with QCI who were exposed to AC medications might have higher global cognitive scores than those without AC exposure. The observed associations indicate that older adults might experience some beneficial cognitive effects from AC drugs, possibly due to the therapeutic effects of these medications in controlling comorbidities; thus, outweighing their adverse effects on cognition. PMID:27638818

A putative positive feedback regulation mechanism in CsACS2 expression suggests a modified model for sex determination in cucumber (Cucumis sativus L.)

PubMed Central

Wang, Shu; Tao, Qianyi; Pan, Junsong; Si, Longting; Gong, Zhenhui; Cai, Run

2012-01-01

It is well established that the plant hormone ethylene plays a key role in cucumber sex determination. Since the unisexual control gene M was cloned and shown to encode an ethylene synthase, instead of an ethylene receptor, the ‘one-hormone hypothesis’, which was used to explain the cucumber sex phenotype, has been challenged. Here, the physiological function of CsACS2 (the gene encoded by the M locus) was studied using the transgenic tobacco system. The results indicated that overexpression of CsACS2 increased ethylene production in the tobacco plant, and the native cucumber promoter had no activity in transgenic tobacco (PM). However, when PM plants were treated with exogenous ethylene, CsACS2 expression could be detected. In cucumber, ethylene treatment could also induce transcription of CsACS2, while inhibition of ethylene action reduced the expression level. These findings suggest a positive feedback regulation mechanism for CsACS2, and a modified ‘one-hormone hypothesis’ for sex determination in cucumber is proposed. PMID:22577183

A putative positive feedback regulation mechanism in CsACS2 expression suggests a modified model for sex determination in cucumber (Cucumis sativus L.).

PubMed

Li, Zheng; Wang, Shu; Tao, Qianyi; Pan, Junsong; Si, Longting; Gong, Zhenhui; Cai, Run

2012-07-01

It is well established that the plant hormone ethylene plays a key role in cucumber sex determination. Since the unisexual control gene M was cloned and shown to encode an ethylene synthase, instead of an ethylene receptor, the 'one-hormone hypothesis', which was used to explain the cucumber sex phenotype, has been challenged. Here, the physiological function of CsACS2 (the gene encoded by the M locus) was studied using the transgenic tobacco system. The results indicated that overexpression of CsACS2 increased ethylene production in the tobacco plant, and the native cucumber promoter had no activity in transgenic tobacco (PM). However, when PM plants were treated with exogenous ethylene, CsACS2 expression could be detected. In cucumber, ethylene treatment could also induce transcription of CsACS2, while inhibition of ethylene action reduced the expression level. These findings suggest a positive feedback regulation mechanism for CsACS2, and a modified 'one-hormone hypothesis' for sex determination in cucumber is proposed.

Efficient Actor-Critic Algorithm with Hierarchical Model Learning and Planning

PubMed Central

Fu, QiMing

2016-01-01

To improve the convergence rate and the sample efficiency, two efficient learning methods AC-HMLP and RAC-HMLP (AC-HMLP with ℓ 2-regularization) are proposed by combining actor-critic algorithm with hierarchical model learning and planning. The hierarchical models consisting of the local and the global models, which are learned at the same time during learning of the value function and the policy, are approximated by local linear regression (LLR) and linear function approximation (LFA), respectively. Both the local model and the global model are applied to generate samples for planning; the former is used only if the state-prediction error does not surpass the threshold at each time step, while the latter is utilized at the end of each episode. The purpose of taking both models is to improve the sample efficiency and accelerate the convergence rate of the whole algorithm through fully utilizing the local and global information. Experimentally, AC-HMLP and RAC-HMLP are compared with three representative algorithms on two Reinforcement Learning (RL) benchmark problems. The results demonstrate that they perform best in terms of convergence rate and sample efficiency. PMID:27795704

Efficient Actor-Critic Algorithm with Hierarchical Model Learning and Planning.

PubMed

Zhong, Shan; Liu, Quan; Fu, QiMing

2016-01-01

To improve the convergence rate and the sample efficiency, two efficient learning methods AC-HMLP and RAC-HMLP (AC-HMLP with ℓ 2 -regularization) are proposed by combining actor-critic algorithm with hierarchical model learning and planning. The hierarchical models consisting of the local and the global models, which are learned at the same time during learning of the value function and the policy, are approximated by local linear regression (LLR) and linear function approximation (LFA), respectively. Both the local model and the global model are applied to generate samples for planning; the former is used only if the state-prediction error does not surpass the threshold at each time step, while the latter is utilized at the end of each episode. The purpose of taking both models is to improve the sample efficiency and accelerate the convergence rate of the whole algorithm through fully utilizing the local and global information. Experimentally, AC-HMLP and RAC-HMLP are compared with three representative algorithms on two Reinforcement Learning (RL) benchmark problems. The results demonstrate that they perform best in terms of convergence rate and sample efficiency.

Design of a probe for two-dimensional small angle detection

NASA Astrophysics Data System (ADS)

He, Haixia; Wang, Xuanze; Zhong, Yuning; Yang, Liangen; Cao, Hongduan

2008-10-01

A novel two-dimensional small angle probe is introduced, which is based on principle of auto-collimation and utilizes quadrant Si-photoelectric detector (QPD) as detection device. AC modulation, AC magnification and absolute value demodulation are incorporated to restrain the DC excursion caused by background light and noise etc and to improve the sensitivity and stability of angle detection. To ensure that while the laser is shining, the current signal (converted into voltage signal) of QPD also is linear to the AC modulation voltage, this paper adopted AC modulation signal (5400Hz) with a DC offset. AC magnification circuit with reasonable parameters is designed to inhibit DC drift and the impact of industrial frequency noise and to ensure good amplification to signal frequency at the same time. A piezoelectric-driven micro-angle generator is designed to demarcate the angle. The calibration data are input to single chip, and the measurement of angles can be shown in SMC1602A.

Quantification of four artificial sweeteners in Finnish surface waters with isotope-dilution mass spectrometry.

PubMed

Perkola, Noora; Sainio, Pirjo

2014-01-01

The artificial sweeteners sucralose (SCL), acesulfame (ACS), saccharin (SAC), and cyclamate (CYC) have been detected in environmental waters in Europe and North America. Higher environmental levels are expected in view of the increasing consumption of these food additives. In this study, an isotope-dilution mass spectrometry (IDMS) LC-MS/MS method was developed and validated for quantifying the four artificial sweeteners in boreal lakes (n = 3) and rivers (n = 12). The highest concentrations of ACS, SAC, CYC and SCL were 9,600, 490, 210 and 1000 ng/L, respectively. ACS and SAC were detected in all studied samples, and CYC and SCL in 98% and 56% of the samples. Seasonal trends of ACS and SAC were observed in some rivers. ACS and SCL concentrations in rivers correlated linearly with population equivalents of the wastewater treatment plants in the catchment areas, whereas SAC and CYC concentrations depend more on the source. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Psychosocial Context Impacts Medication Adherence after Acute Coronary Syndrome

PubMed Central

Kronish, Ian M.; Rieckmann, Nina; Burg, Matthew M.; Alcántara, Carmela; Davidson, Karina W.

2013-01-01

Background Depression is associated with poor adherence to medications and worse prognosis in patients with acute coronary syndrome (ACS). Purpose To determine whether cognitive, behavioral, and/or psychosocial vulnerabilities for depression explain the association between depression and medication adherence among ACS patients. Methods 169 ACS patients who agreed to have their aspirin adherence measured using an electronic pill bottle for 3 months were enrolled within 1 week of hospitalization. Linear regression was used to determine whether depression vulnerabilities predicted aspirin adherence after adjustment for depressive symptoms, demographics, and comorbidity. Results Of the depression vulnerabilities, only role transitions (beta = −3.32; p=0.02) and interpersonal conflict (beta −3.78; p=0.03) predicted poor adherence. Depression vulnerabilities did not mediate the association between depressive symptoms and medication adherence. Conclusions Key elements of the psychosocial context preceding the ACS including major role transitions and conflict with close contacts place ACS patients at increased risk for poor medication adherence independent of depressive symptoms. PMID:24163188

Sociodemographic and Environmental Correlates of Active Commuting in Rural America

PubMed Central

Fan, Jessie X.; Wen, Ming; Kowaleski-Jones, Lori

2014-01-01

Purpose This research investigated participation rates in 3 modes of active commuting (AC) and their sociodemographic and physical environmental correlates in rural America. Methods The 2000 Census supplemented with other datasets were used to analyze AC rates in percentage of workers walking, biking, and taking public transportations to work in 14,209 nonmetropolitan rural tracts identified by RUCA codes, including 4,067 small rural and 10,142 town-micropolitan rural tracts. Sociodemographic and physical environmental variables were correlated with 3 AC modes simultaneously using Seemingly Unrelated Regression for nonmetro rural, and for small rural and town-micropolitan rural separately. Findings The average AC rates in rural tracts were 3.63%, 0.26%, and 0.56% for walking, biking, and public transportation to work, respectively, with small rural tracts having a higher rate of walking but lower rates of biking and public transportation to work than town-micropolitan tracts. In general, better economic well-being was negatively associated with AC but percentage of college-educated was a positive correlate. Population density was positively associated with AC but greenness and proximity to parks were negative correlates. However, significant differences existed for different AC modes, and between small rural and town-micropolitan rural tracts. Conclusions Sociodemographic factors explained more variance in AC than physical environmental factors but the detailed relationships were complex, varying by AC mode and by degree of rurality. Any strategy to promote AC in rural America needs to be sensitive to the population size of the area and assessed in a comprehensive manner to avoid a “one size fits all” approach. PMID:25066252

Sociodemographic and environmental correlates of active commuting in rural America.

PubMed

Fan, Jessie X; Wen, Ming; Kowaleski-Jones, Lori

2015-01-01

This research investigated participation rates in 3 modes of active commuting (AC) and their sociodemographic and physical environmental correlates in rural America. The 2000 Census supplemented with other data sets were used to analyze AC rates in percentage of workers walking, biking, and taking public transportation to work in 14,209 nonmetropolitan rural tracts identified by RUCA codes, including 4,067 small rural and 10,142 town-micropolitan rural tracts. Sociodemographic and physical environmental variables were correlated with 3 AC modes simultaneously using Seemingly Unrelated Regression for nonmetro rural, and for small rural and town-micropolitan rural separately. The average AC rates in rural tracts were 3.63%, 0.26%, and 0.56% for walking, biking, and public transportation to work, respectively, with small rural tracts having a higher rate of walking but lower rates of biking and public transportation to work than town-micropolitan tracts. In general, better economic well-being was negatively associated with AC but percentage of college-educated was a positive correlate. Population density was positively associated with AC but greenness and proximity to parks were negative correlates. However, significant differences existed for different AC modes, and between small rural and town-micropolitan rural tracts. Sociodemographic factors explained more variance in AC than physical environmental factors but the detailed relationships were complex, varying by AC mode and by degree of rurality. Any strategy to promote AC in rural America needs to be sensitive to the population size of the area and assessed in a comprehensive manner to avoid a "one size fits all" approach. © 2014 National Rural Health Association.

Prevalence of heroin markers in urine for pain management patients.

PubMed

Knight, Julie; Puet, Brandi L; DePriest, Anne; Heltsley, Rebecca; Hild, Cheryl; Black, David L; Robert, Timothy; Caplan, Yale H; Cone, Edward J

2014-10-01

Surveys of current trends indicate heroin abuse is associated with nonmedical use of pain relievers. Consequently, there is an interest in evaluating the presence of heroin-specific markers in chronic pain patients who are prescribed controlled substances. A total of 926,084 urine specimens from chronic pain patients were tested for heroin/diacetylmorphine (DAM), 6-acetylmorphine (6AM), 6-acetylcodeine (6AC), codeine (COD), and morphine (MOR). Heroin and markers were analyzed using liquid chromatography tandem mass spectrometry (LC-MS-MS). Opiates were analyzed following hydrolysis using LC-MS-MS. The prevalence of heroin use was 0.31%, as 2871 were positive for one or more heroin-specific markers including DAM, 6AM, or 6AC (a known contaminant of illicit heroin). Of these, 1884 were additionally tested for the following markers of illicit drug use: 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), methamphetamine (MAMP), 11-nor-9-carboxy-Δ(9)-tetracannabinol (THCCOOH), and benzoylecgonine (BZE); 654 (34.7%) had positive findings for one or more of these analytes. The overall prevalence of heroin markers were as follows: DAM 1203 (41.9%), 6AM 2570 (89.5%), 6AC 1082 (37.7%). MOR was present in 2194 (76.4%) and absent (

Second Order Non-Linear Optical Polyphosphazenes. Proceedings of Symposium on Non-Linear Optics, ACS Meeting, Held in Boston, Massachusetts 1990

DTIC Science & Technology

1990-03-23

Paciorek Dr. William B. Moniz Ultrasystems Defense and Space, Inc. Code 6120 16775 Von Karman Avenue Naval Research Laboratory Irvine, CA 92714 Washington...413h004 Dr. Les H. Sperling Dr. Richard S. Stein Materials Research Center #32 Polymer Research Institute Lehigh University University of Massachusetts

1995 second modulator-klystron workshop: A modulator-klystron workshop for future linear colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-03-01

This second workshop examined the present state of modulator design and attempted an extrapolation for future electron-positron linear colliders. These colliders are currently viewed as multikilometer-long accelerators consisting of a thousand or more RF sources with 500 to 1,000, or more, pulsed power systems. The workshop opened with two introductory talks that presented the current approaches to designing these linear colliders, the anticipated RF sources, and the design constraints for pulse power. The cost of main AC power is a major economic consideration for a future collider, consequently the workshop investigated efficient modulator designs. Techniques that effectively apply the artmore » of power conversion, from the AC mains to the RF output, and specifically, designs that generate output pulses with very fast rise times as compared to the flattop. There were six sessions that involved one or more presentations based on problems specific to the design and production of thousands of modulator-klystron stations, followed by discussion and debate on the material.« less

Insight into climate change from the carbon exchange of biocrusts utilizing non-rainfall water.

PubMed

Ouyang, Hailong; Hu, Chunxiang

2017-05-31

Biocrusts are model ecosystems of global change studies. However, light and non-rainfall water (NRW) were previously few considered. Different biocrust types further aggravated the inconsistence. So carbon-exchange of biocrusts (cyanobacteria crusts-AC1/AC2; cyanolichen crust-LC1; chlorolichen crust-LC2; moss crust-MC) utilizing NRW at various temperatures and light-intensities were determined under simulated and insitu mesocosm experiments. Carbon input of all biocrusts were negatively correlated with experimental temperature under all light-intensity with saturated water and stronger light with equivalent NRW, but positively correlated with temperature under weak light with equivalent NRW. LCPs and R/Pg of AC1 were lowest, followed in turn by AC2, LC2 and MC. Thus AC1 had most opportunities to use NRW, and 2.5 °C warming did cause significant changes of carbon exchange. Structural equation models further revealed that air-temperature was most important for carbon-exchange of ACs, but equally important as NRW for LC2 and MC; positive influence of warming on carbon-input in ACs was much stronger than the latter. Therefore, temperature effect on biocrust carbon-input depends on both moisture and light. Meanwhile, the role of NRW, transitional states between ACs, and obvious carbon-fixation differences between lichen crusts should be fully considered in the future study of biocrusts responding to climate change.

Two anomalous cardiovascular responses to active standing in essential hypertension.

PubMed

Bettencourt, M Joaquina; Pinto, Basílio Gomes; de Oliveira, E Infante; Silva-Carvalho, L

2008-05-01

In a previous work we studied, non-invasively, autonomic nervous system control of circulation in healthy subjects, observing the hemodynamic reaction to active standing. We now propose to extend this analysis to essential hypertension (EH), investigating possible autonomic dysfunction. The cardiovascular response to postural change from the supine position to active standing of 48 EH patients, of both sexes, with and without medication, was compared with that obtained for healthy subjects. We evaluated arterial systolic (SBP) and diastolic (DBP) blood pressure, stroke volume (SV), inotropic index (INOI), total vascular resistance (TVR), cardiac work (W), stroke work (SW), arterial compliance (AC) and heart rate (HR), using the entirely non-invasive BoMed NCCOM3 thoracic electrical bioimpedance monitor and sphygmomanometry. We found two patient groups characterized by different linear relationships between values of cardiovascular variables in active standing and in supine positions. Except for HR, in both groups these regression lines differed from normal. Compared to the supine position, in active standing, one group (EH-I) presented increased TVR, diminished SV, INOI, W, SW, and AC, and normal HR; the other group (EH-II) presented diminished TVR and HR and increased SV, INOI, W, SW and AC. The two patient groups could be separated on the basis of their age, but not on the basis of their systolic, diastolic and mean arterial blood pressures, gender or medication. The younger patient group (EH-I) included 28 subjects aged 24 to 69 years (50+/-10), of whom 11 were unmedicated, and the older patient group (EH-II) included 20 subjects aged 35 to 75 years (62+/-11), of whom 7 were unmedicated. Our results show a depressed response in postural change for older patients, which in the autonomic control of circulation expresses carotid baroreflex impairment, and conversely an enhanced response for younger patients, which can be caused by a maladjustment of the influence of cardiopulmonary mechanoreflexes in the alance with arterial baroreflexes. This work suggests the existence of two different levels of dysautonomia in EH, according to age. The deterministic changes in cardiovascular variables after postural change show that, regarding autonomic nervous system control to maintain homeostasis, certain circulatory statuses are favored.

The influence of changes in blood flow on the accuracy of pulse oximetry in humans.

PubMed

Vegfors, M; Lindberg, L G; Lennmarken, C

1992-05-01

Oxygen saturation (SpO2) was measured with a pulse oximeter in ten healthy, young men breathing air. A pulse oximeter probe was attached to the second toe and a laser Doppler probe to the first toe of the same foot for measurement of changes in peripheral blood flow. The pulse oximeter and laser Doppler readings were simultaneously compared when the foot was positioned 40 cm (position 1) above heart level, elevated 10 cm (position 2) above heart level and horizontally at heart level (position 3). Using this experimental human model, we achieved various blood flows. The AC and DC optical signals used for determination of oxygen saturation were recorded from the pulse oximeter and analysed. There was a significant increase (P less than 0.05) between position 1 and 3 in blood flow as measured by the laser Doppler flow meter. The corresponding pulse oximeter readings of haemoglobin saturation also increased significantly (P less than 0.05) comparing these two leg positions. Analysing the AC- and DC optical signals, the AC value of infrared light increased considerably, while the AC value of the red light decreased slightly. The DC values of red and infrared light did not change significantly. In summary, when blood flow was decreased, the ratio of red to infrared transmitted light was changed, resulting in a low SpO2 reading.

Linear ac Response of Thin Superconductors during Flux Creep

NASA Astrophysics Data System (ADS)

Brandt, Ernst Helmut; Gurevich, Alexander

1996-03-01

The linear magnetic susceptibility χ\\(ω\\) of superconducting strips and disks in a transverse magnetic field is calculated in the flux-creep regime. It is shown that χ\\(ω\\) = χ'-iχ'' for ω>>1/t is universal, independent of temperature, dc field, and material parameters, depending only on the sample shape, ac frequency ω/2π, and time t elapsed after creep has started. Qualitatively, χ\\(ω\\) can be obtained from the χ\\(ω\\) of metallic conductors by replacing the Ohmic relaxation time by t. At ωt>>1, which may apply down to rather low frequencies, the dissipative flux-creep state exhibits a nearly Meissner-like response with χ' = -1+0.40/ωt and χ'' = 0.25ln\\(29ωt\\)/ωt for disks.

Adjuvant trastuzumab in HER2-positive breast cancer.

PubMed

Slamon, Dennis; Eiermann, Wolfgang; Robert, Nicholas; Pienkowski, Tadeusz; Martin, Miguel; Press, Michael; Mackey, John; Glaspy, John; Chan, Arlene; Pawlicki, Marek; Pinter, Tamas; Valero, Vicente; Liu, Mei-Ching; Sauter, Guido; von Minckwitz, Gunter; Visco, Frances; Bee, Valerie; Buyse, Marc; Bendahmane, Belguendouz; Tabah-Fisch, Isabelle; Lindsay, Mary-Ann; Riva, Alessandro; Crown, John

2011-10-06

Trastuzumab improves survival in the adjuvant treatment of HER-positive breast cancer, although combined therapy with anthracycline-based regimens has been associated with cardiac toxicity. We wanted to evaluate the efficacy and safety of a new nonanthracycline regimen with trastuzumab. We randomly assigned 3222 women with HER2-positive early-stage breast cancer to receive doxorubicin and cyclophosphamide followed by docetaxel every 3 weeks (AC-T), the same regimen plus 52 weeks of trastuzumab (AC-T plus trastuzumab), or docetaxel and carboplatin plus 52 weeks of trastuzumab (TCH). The primary study end point was disease-free survival. Secondary end points were overall survival and safety. At a median follow-up of 65 months, 656 events triggered this protocol-specified analysis. The estimated disease-free survival rates at 5 years were 75% among patients receiving AC-T, 84% among those receiving AC-T plus trastuzumab, and 81% among those receiving TCH. Estimated rates of overall survival were 87%, 92%, and 91%, respectively. No significant differences in efficacy (disease-free or overall survival) were found between the two trastuzumab regimens, whereas both were superior to AC-T. The rates of congestive heart failure and cardiac dysfunction were significantly higher in the group receiving AC-T plus trastuzumab than in the TCH group (P<0.001). Eight cases of acute leukemia were reported: seven in the groups receiving the anthracycline-based regimens and one in the TCH group subsequent to receiving an anthracycline outside the study. The addition of 1 year of adjuvant trastuzumab significantly improved disease-free and overall survival among women with HER2-positive breast cancer. The risk-benefit ratio favored the nonanthracycline TCH regimen over AC-T plus trastuzumab, given its similar efficacy, fewer acute toxic effects, and lower risks of cardiotoxicity and leukemia. (Funded by Sanofi-Aventis and Genentech; BCIRG-006 ClinicalTrials.gov number, NCT00021255.).

Adjuvant Trastuzumab in HER2-Positive Breast Cancer

PubMed Central

Slamon, Dennis; Eiermann, Wolfgang; Robert, Nicholas; Pienkowski, Tadeusz; Martin, Miguel; Press, Michael; Mackey, John; Glaspy, John; Chan, Arlene; Pawlicki, Marek; Pinter, Tamas; Valero, Vicente; Liu, Mei-Ching; Sauter, Guido; von Minckwitz, Gunter; Visco, Frances; Bee, Valerie; Buyse, Marc; Bendahmane, Belguendouz; Tabah-Fisch, Isabelle; Lindsay, Mary-Ann; Riva, Alessandro; Crown, John

2011-01-01

BACKGROUND Trastuzumab improves survival in the adjuvant treatment of HER-positive breast cancer, although combined therapy with anthracycline-based regimens has been associated with cardiac toxicity. We wanted to evaluate the efficacy and safety of a new nonanthracycline regimen with trastuzumab. METHODS We randomly assigned 3222 women with HER2-positive early-stage breast cancer to receive doxorubicin and cyclophosphamide followed by docetaxel every 3 weeks (AC-T), the same regimen plus 52 weeks of trastuzumab (AC-T plus trastuzumab), or docetaxel and carboplatin plus 52 weeks of trastuzumab (TCH). The primary study end point was disease-free survival. Secondary end points were overall survival and safety. RESULTS At a median follow-up of 65 months, 656 events triggered this protocol-specified analysis. The estimated disease-free survival rates at 5 years were 75% among patients receiving AC-T, 84% among those receiving AC-T plus trastuzumab, and 81% among those receiving TCH. Estimated rates of overall survival were 87%, 92%, and 91%, respectively. No significant differences in efficacy (disease-free or overall survival) were found between the two trastuzumab regimens, whereas both were superior to AC-T. The rates of congestive heart failure and cardiac dysfunction were significantly higher in the group receiving AC-T plus trastuzumab than in the TCH group (P<0.001). Eight cases of acute leukemia were reported: seven in the groups receiving the anthracycline-based regimens and one in the TCH group subsequent to receiving an anthracycline outside the study. CONCLUSIONS The addition of 1 year of adjuvant trastuzumab significantly improved disease-free and overall survival among women with HER2-positive breast cancer. The risk–benefit ratio favored the nonanthracycline TCH regimen over AC-T plus trastuzumab, given its similar efficacy, fewer acute toxic effects, and lower risks of cardiotoxicity and leukemia. (Funded by Sanofi-Aventis and Genentech; BCIRG-006 ClinicalTrials.gov number, NCT00021255.) PMID:21991949

Combined Effect of Alternating Current Interference and Cathodic Protection on Pitting Corrosion and Stress Corrosion Cracking Behavior of X70 Pipeline Steel in Near-Neutral pH Environment.

PubMed

Wang, Liwei; Cheng, Lianjun; Li, Junru; Zhu, Zhifu; Bai, Shuowei; Cui, Zhongyu

2018-03-22

Influence of alternating current (AC) on pitting corrosion and stress corrosion cracking (SCC) behavior of X70 pipeline steel in the near-neutral pH environment under cathodic protection (CP) was investigated. Both corrosion and SCC are inhibited by -0.775 V SCE CP without AC interference. With the superimposition of AC current (1-10 mA/cm²), the direct current (DC) potential shifts negatively under the CP of -0.775 V SCE and the cathodic DC current decreases and shifts to the anodic direction. Under the CP potential of -0.95 V SCE and -1.2 V SCE , the applied AC current promotes the cathodic reaction and leads to the positive shift of DC potential and increase of cathodic current. Local anodic dissolution occurs attributing to the generated anodic current transients in the positive half-cycle of the AC current, resulting in the initiation of corrosion pits (0.6-2 μm in diameter). AC enhances the SCC susceptibility of X70 steel under -0.775 V SCE CP, attributing to the promotion of anodic dissolution and hydrogen evolution. Even an AC current as low as 1 mA/cm² can enhance the SCC susceptibility.

Performance Estimation for Two-Dimensional Brownian Rotary Ratchet Systems

NASA Astrophysics Data System (ADS)

Tutu, Hiroki; Horita, Takehiko; Ouchi, Katsuya

2015-04-01

Within the context of the Brownian ratchet model, a molecular rotary system that can perform unidirectional rotations induced by linearly polarized ac fields and produce positive work under loads was studied. The model is based on the Langevin equation for a particle in a two-dimensional (2D) three-tooth ratchet potential of threefold symmetry. The performance of the system is characterized by the coercive torque, i.e., the strength of the load competing with the torque induced by the ac driving field, and the energy efficiency in force conversion from the driving field to the torque. We propose a master equation for coarse-grained states, which takes into account the boundary motion between states, and develop a kinetic description to estimate the mean angular momentum (MAM) and powers relevant to the energy balance equation. The framework of analysis incorporates several 2D characteristics and is applicable to a wide class of models of smooth 2D ratchet potential. We confirm that the obtained expressions for MAM, power, and efficiency of the model can enable us to predict qualitative behaviors. We also discuss the usefulness of the torque/power relationship for experimental analyses, and propose a characteristic for 2D ratchet systems.

Block of Brain Sodium Channels by Peptide Mimetics of the Isoleucine, Phenylalanine, and Methionine (IFM) Motif from the Inactivation Gate

PubMed Central

Eaholtz, Galen; Colvin, Anita; Leonard, Daniele; Taylor, Charles; Catterall, William A.

1999-01-01

Inactivation of sodium channels is thought to be mediated by an inactivation gate formed by the intracellular loop connecting domains III and IV. A hydrophobic motif containing the amino acid sequence isoleucine, phenylalanine, and methionine (IFM) is required for the inactivation process. Peptides containing the IFM motif, when applied to the cytoplasmic side of these channels, produce two types of block: fast block, which resembles the inactivation process, and slow, use-dependent block stimulated by strong depolarizing pulses. Fast block by the peptide ac-KIFMK-NH2, measured on sodium channels whose inactivation was slowed by the α-scorpion toxin from Leiurus quinquestriatus (LqTx), was reversed with a time constant of 0.9 ms upon repolarization. In contrast, control and LqTx-modified sodium channels were slower to recover from use-dependent block. For fast block, linear peptides of three to six amino acid residues containing the IFM motif and two positive charges were more effective than peptides with one positive charge, whereas uncharged IFM peptides were ineffective. Substitution of the IFM residues in the peptide ac-KIFMK-NH2 with smaller, less hydrophobic residues prevented fast block. The positively charged tripeptide IFM-NH2 did not cause appreciable fast block, but the divalent cation IFM-NH(CH2)2NH2 was as effective as the pentapeptide ac-KIFMK-NH2. The constrained peptide cyclic KIFMK containing two positive charges did not cause fast block. These results indicate that the position of the positive charges is unimportant, but flexibility or conformation of the IFM-containing peptide is important to allow fast block. Slow, use-dependent block was observed with IFM-containing peptides of three to six residues having one or two positive charges, but not with dipeptides or phenylalanine-amide. In contrast to its lack of fast block, cyclic KIFMK was an effective use-dependent blocker. Substitutions of amino acid residues in the tripeptide IFM-NH2 showed that large hydrophobic residues are preferred in all three positions for slow, use-dependent block. However, substitution of the large hydrophobic residue diphenylalanine or the constrained residues phenylglycine or tetrahydroisoquinoline for phe decreased potency, suggesting that this phe residue must be able to enter a restricted hydrophobic pocket during the binding of IFM peptides. Together, the results on fast block and slow, use-dependent block indicate that IFM peptides form two distinct complexes of different stability and structural specificity with receptor site(s) on the sodium channel. It is proposed that fast block represents binding of these peptides to the inactivation gate receptor, while slow, use-dependent block represents deeper binding of the IFM peptides in the pore. PMID:9925825

Anatomical landmark position--can we trust what we see? Results from an online reliability and validity study of osteopaths.

PubMed

Pattyn, Elise; Rajendran, Dévan

2014-04-01

Practitioners traditionally use observation to classify the position of patients' anatomical landmarks. This information may contribute to diagnosis and patient management. To calculate a) Inter-rater reliability of categorising the sagittal plane position of four anatomical landmarks (lateral femoral epicondyle, greater trochanter, mastoid process and acromion) on side-view photographs (with landmarks highlighted and not-highlighted) of anonymised subjects; b) Intra-rater reliability; c) Individual landmark inter-rater reliability; d) Validity against a 'gold standard' photograph. Online inter- and intra-rater reliability study. Photographed subjects: convenience sample of asymptomatic students; raters: randomly selected UK registered osteopaths. 40 photographs of 30 subjects were used, a priori clinically acceptable reliability was ≥0.4. Inter-rater arm: 20 photographs without landmark highlights plus 10 with highlights; Intra-rater arm: 10 duplicate photographs (non-highlighted landmarks). Validity arm: highlighted landmark scores versus 'gold standard' photographs with vertical line. Research ethics approval obtained. Osteopaths (n = 48) categorised landmark position relative to imagined vertical-line; Gwet's Agreement Coefficient 1 (AC1) calculated and chance-corrected coefficient benchmarked against Landis and Koch's scale; Validity calculation used Kendall's tau-B. Inter-rater reliability was 'fair' (AC1 = 0.342; 95% confidence interval (CI) = 0.279-0.404) for non-highlighted landmarks and 'moderate' (AC1 = 0.700; 95% CI = 0.596-0.805) for highlighted landmarks. Intra-rater reliability was 'fair' (AC1 = 0.522); range was 'poor' (AC1 = 0.160) to 'substantial' (AC1 = 0.896). No differences were found between individual landmarks. Validity was 'low' (TB = 0.327; p = 0.104). Both inter- and intra-rater reliability was 'fair' but below clinically acceptable levels, validity was 'low'. Together these results challenge the clinical practice of using observation to categorise anterio-posterior landmark position. Copyright © 2014 Elsevier Ltd. All rights reserved.

7-aminoclonazepam is superior to clonazepam for detection of clonazepam use in oral fluid by LC-MS/MS.

PubMed

Melanson, Stacy E F; Griggs, David; Bixho, Ida; Khaliq, Tahira; Flood, James G

2016-04-01

Clonazepam (CLON) is not only frequently prescribed in addiction management but is also commonly abused. Therefore many addiction clinics perform oral fluid (OF) testing, which unlike urine is not subject to adulteration, to monitor CLON compliance. However, CLON and other benzodiazepines can be challenging to detect in OF due to their weakly acidic nature and their presence in low concentrations. We determined the optimal technical and clinical approach for the detection of CLON use using OF. We measured CLON and its primary metabolite 7-aminoclonazepam (7AC) by liquid chromatography-tandem mass spectrometry in OF specimens over a 2 month period. The samples were collected using the Orasure Intercept OF sample collection device. One hundred samples were presumptive-positive for 7AC and/or CLON. 91 (91.0%) confirmed positive for 7AC (median, range: 4.2, 0.5-316.7 ng/ml) using the ion ratio test, while only 44 of the 100 (44.0%) samples confirmed positive for CLON (median, range: 3.7, 0.5-217.2 ng/ml) using the ion ratio test. In OF the levels of 7AC were approximately 2.4-fold higher than CLON. The use of 7AC as an analyte for the detection of both CLON compliance and undisclosed use is also recommended. 7AC should be the analyte measured in OF for the detection of CLON use. Copyright © 2016 Elsevier B.V. All rights reserved.

Combined orbits and clocks from the IGS 2nd reprocessing

NASA Astrophysics Data System (ADS)

Griffiths, J.; Ray, J.

2016-12-01

In early 2015, the Analysis Centers (ACs) of the International GNSS Service (IGS) completed their second reanalysis of the full history of globally distributed GPS and GLONASS data collected since 1994. The suite of reprocessed AC solutions includes daily product files containing station positions, Earth rotation parameters, satellite orbits and clocks. This second reprocessing—or repro2—provided the IGS contribution to ITRF2014; it follows the successful first reprocessing, which provided the IGS input for ITRF2008. For this poster, we will discuss the newly combined repro2 GPS orbits and clocks. We also revisit our previous analysis of orbit day-boundary discontinuities with several significant changes and improvements: 1) Orbit discontinuities for the contributing ACs were studied in addition to those for the IGS repro2 combined orbits. (2) Apart from homogeneous reprocessing with updated analysis models, the main difference compared to the IGS Final operational products is that NOAA/NGS inputs were not submitted for the IGS reprocessing, yet they contribute heavily in the operational orbits in recent years. (3) Also, during spring 2016, the ESA modified their orbit model so that it is no longer consistent with the one used for reprocessing. A much longer span of orbits was available now, up to 11.2 years for some individual satellites, which allows a far better resolution of spectral features. 4) The procedure to compute orbit discontinuities has been further refined to account for extrapolation edge effects, improved geopotential fields, and to allow for spectral analysis of a longer time series of jumps. The satellite position time series used are complete enough that linear interpolation is necessary for only sparse gaps. So the key results are based on standard FFT power spectra (stacked over the available constellation and lightly smoothed). However, we have also computed Lomb-Scargle periodgrams to provide higher frequency resolution of some spectral peaks and to permit tests of the effect of excluding eclipse periods.

A new venous infusion pathway monitoring system.

PubMed

Maki, Hiromichi; Yonezawa, Yoshiharu; Ogawa, Hidekuni; Ninomiya, Ishio; Sata, Koji; Hamada, Shingo; Caldwell, W Morton

2007-01-01

A new infusion catheter pathway monitoring system employing linear integrated circuits and a low-power 8-bit single chip microcomputer has been developed for hospital and home use. The sensor consists of coaxial three-layer conductive tapes wrapped around the polyvinyl chloride infusion tube. The inner tape is the main electrode, which records an AC (alternating current) voltage induced on the patient's body by electrostatic coupling from the normal 100 volt, 60 Hz AC power line wiring field in the patient's room. The outside tape layer is a reference electrode to monitor the AC voltage around the main electrode. The center tape layer is connected to system ground and functions as a shield. The microcomputer calculates the ratio of the induced AC voltages recorded by the main and reference electrodes and if the ratio indicates a detached infusion, alerts the nursing station, via the nurse call system or low transmitting power mobile phone.

Inflammatory role and prognostic value of platelet chemokines in acute coronary syndrome.

PubMed

Blanchet, X; Cesarek, K; Brandt, J; Herwald, H; Teupser, D; Küchenhoff, H; Karshovska, E; Mause, S F; Siess, W; Wasmuth, H; Soehnlein, O; Koenen, R R; Weber, C; von Hundelshausen, P

2014-12-01

Activated platelets and neutrophils exacerbate atherosclerosis. Platelets release the chemokines CXCL4, CXCL4L1 and CCL5, whereas myeloperoxidase (MPO) and azurocidin are neutrophil-derived. We investigated whether plasma levels of these platelet and neutrophil mediators are affected by the acute coronary syndrome (ACS), its medical treatment, concomitant clinical or laboratory parameters, and predictive for the progression of coronary artery disease (CAD). In an observational study, the association of various factors with plasma concentrations of platelet chemokines and neutrophil mediators in 204 patients, either upon admission with ACS and 6 hours later or without ACS or CAD, was determined by multiple linear regression. Mediator release was further analysed after activation of blood with ACS-associated triggers such as plaque material. CXCL4, CXCL4L1, CCL5, MPO and azurocidin levels were elevated in ACS. CXCL4 and CCL5 but not CXCL4L1 or MPO were associated with platelet counts and CRP. CXCL4 (in association with heparin treatment) and MPO declined over 6 hours during ACS. Elevated CCL5 was associated with a progression of CAD. Incubating blood with plaque material, PAR1 and PAR4 activation induced a marked release of CXCL4 and CCL5, whereas CXCL4L1 and MPO were hardly or not altered. Platelet chemokines and neutrophil products are concomitantly elevated in ACS and differentially modulated by heparin treatment. CCL5 levels during ACS predict a progression of preexisting CAD. Platelet-derived products appear to dominate the inflammatory response during ACS, adding to the emerging evidence that ACS per se may promote vascular inflammation.

Chromatographic enantioseparation by poly(biphenylylacetylene) derivatives with memory of both axial chirality and macromolecular helicity.

PubMed

Ishidate, Ryoma; Ikai, Tomoyuki; Kanoh, Shigeyoshi; Yashima, Eiji; Maeda, Katsuhiro

2017-03-01

Novel poly(biphenylylacetylene) derivatives bearing two acetyloxy groups at the 2- and 2'-positions and an alkoxycarbonyl group at the 4'-position of the biphenyl pendants (poly-Ac's) were synthesized by the polymerization of the corresponding biphenylylacetylenes using a rhodium catalyst. The obtained stereoregular (cis-transoidal) poly-Ac's folded into a predominantly one-handed helical conformation accompanied by a preferred-handed axially twisted conformation of the biphenyl pendants through noncovalent interactions with a chiral alcohol and both the induced main-chain helicity and the pendant axial chirality were maintained, that is, memorized, after complete removal of the chiral alcohol. The stability of the helicity memory of the poly-Ac's in a solution was lower than that of the analogous poly(biphenylylacetylene)s bearing two methoxymethoxy groups at the 2- and 2'-positions of the biphenyl pendants (poly-MOM's). In the solid state, however, the helicity memory of the poly-Ac's was much more stable and showed a better chiral recognition ability toward several racemates than that of the previously reported poly-MOM when used as a chiral stationary phase for high-performance liquid chromatography. In particular, the poly-Ac-based CSP with a helicity memory efficiently separated racemic benzoin derivatives into enantiomers. © 2017 Wiley Periodicals, Inc.

Energy band alignment and electronic states of amorphous carbon surfaces in vacuo and in aqueous environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caro, Miguel A., E-mail: mcaroba@gmail.com; Department of Applied Physics, COMP Centre of Excellence in Computational Nanoscience, Aalto University, Espoo; Määttä, Jukka

2015-01-21

In this paper, we obtain the energy band positions of amorphous carbon (a–C) surfaces in vacuum and in aqueous environment. The calculations are performed using a combination of (i) classical molecular dynamics (MD), (ii) Kohn-Sham density functional theory with the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional, and (iii) the screened-exchange hybrid functional of Heyd, Scuseria, and Ernzerhof (HSE). PBE allows an accurate generation of a-C and the evaluation of the local electrostatic potential in the a-C/water system, HSE yields an improved description of energetic positions which is critical in this case, and classical MD enables a computationally affordable description of water. Ourmore » explicit calculation shows that, both in vacuo and in aqueous environment, the a-C electronic states available in the region comprised between the H{sub 2}/H{sub 2}O and O{sub 2}/H{sub 2}O levels of water correspond to both occupied and unoccupied states within the a-C pseudogap region. These are localized states associated to sp{sup 2} sites in a-C. The band realignment induces a shift of approximately 300 meV of the a-C energy band positions with respect to the redox levels of water.« less

Joint correction of respiratory motion artifact and partial volume effect in lung/thoracic PET/CT imaging.

PubMed

Chang, Guoping; Chang, Tingting; Pan, Tinsu; Clark, John W; Mawlawi, Osama R

2010-12-01

Respiratory motion artifacts and partial volume effects (PVEs) are two degrading factors that affect the accuracy of image quantification in PET/CT imaging. In this article, the authors propose a joint motion and PVE correction approach (JMPC) to improve PET quantification by simultaneously correcting for respiratory motion artifacts and PVE in patients with lung/thoracic cancer. The objective of this article is to describe this approach and evaluate its performance using phantom and patient studies. The proposed joint correction approach incorporates a model of motion blurring, PVE, and object size/shape. A motion blurring kernel (MBK) is then estimated from the deconvolution of the joint model, while the activity concentration (AC) of the tumor is estimated from the normalization of the derived MBK. To evaluate the performance of this approach, two phantom studies and eight patient studies were performed. In the phantom studies, two motion waveforms-a linear sinusoidal and a circular motion-were used to control the motion of a sphere, while in the patient studies, all participants were instructed to breathe regularly. For the phantom studies, the resultant MBK was compared to the true MBK by measuring a correlation coefficient between the two kernels. The measured sphere AC derived from the proposed method was compared to the true AC as well as the ACs in images exhibiting PVE only and images exhibiting both PVE and motion blurring. For the patient studies, the resultant MBK was compared to the motion extent derived from a 4D-CT study, while the measured tumor AC was compared to the AC in images exhibiting both PVE and motion blurring. For the phantom studies, the estimated MBK approximated the true MBK with an average correlation coefficient of 0.91. The tumor ACs following the joint correction technique were similar to the true AC with an average difference of 2%. Furthermore, the tumor ACs on the PVE only images and images with both motion blur and PVE effects were, on average, 75% and 47.5% (10%) of the true AC, respectively, for the linear (circular) motion phantom study. For the patient studies, the maximum and mean AC/SUV on the PET images following the joint correction are, on average, increased by 125.9% and 371.6%, respectively, when compared to the PET images with both PVE and motion. The motion extents measured from the derived MBK and 4D-CT exhibited an average difference of 1.9 mm. The proposed joint correction approach can improve the accuracy of PET quantification by simultaneously compensating for the respiratory motion artifacts and PVE in lung/thoracic PET/CT imaging.

Antibody-capture enzyme-linked immunosorbent assays that use enzyme-labelled antigen for detection of virus-specific immunoglobulin M, A and G in patients with varicella or herpes zoster.

PubMed Central

van Loon, A. M.; van der Logt, J. T.; Heessen, F. W.; Heeren, M. C.; Zoll, J.

1992-01-01

Antibody-capture enzyme-linked immunosorbent assays (AC-ELISA) which use enzyme-labelled antigen were developed for detection of varicella-zoster virus-(VZV) specific IgM, IgA and IgG antibody in patients with varicella or herpes zoster and in sera from healthy individuals. All 18 patients with varicella developed a VZV-IgM and a VZV-IgG response, 17 also a VZV-IgA response. In contrast, all 19 patients with herpes zoster were shown to be positive for VZV-IgA whereas only 13 of these reacted positively for VZV-IgM. A VZV-IgM response was detected in only two sera from 100 healthy individuals and an IgA response in only one. The presence of virus-specific IgA and IgG in the cerebrospinal fluid as determined by AC-ELISA was a useful indicator of VZV infection of the central nervous system. By AC-ELISA, VZV-IgG was detected predominantly in sera from patients with acute or recent VZV infection. Only 14 sera from 100 healthy individuals were positive for VZV-IgG by AC-ELISA, whereas all were positive by an indirect ELISA. These results indicate that AC-ELISA's may be useful assays for determination for acute or recurrent VZV infection, but are not suitable for determination of past infection with this virus. PMID:1312479

Actinic cheilitis: epithelial expression of COX-2 and its association with mast cell tryptase and PAR-2.

PubMed

Rojas, I Gina; Martínez, Alejandra; Brethauer, Ursula; Grez, Patricia; Yefi, Roger; Luza, Sandra; Marchesani, Francisco J

2009-03-01

Cyclooxygenase-2 (COX-2) is overexpressed in various types of human malignancies, including oral cancers. Recent studies have shown that mast cell-derived protease tryptase can induce COX-2 expression by the cleavage of proteinase-activated receptor-2 (PAR-2). Actinic cheilitis (AC) is a premalignant form of lip cancer characterized by an increased density of tryptase-positive mast cells. To investigate the possible contribution of tryptase to COX-2 overexpression during early lip carcinogenesis, normal lip (n=24) and AC (n=45) biopsies were processed for COX-2, PAR-2 and tryptase detection, using RT-PCR and immunohistochemistry. Expression scores were obtained for each marker and tested for statistical significance using Mann-Whitney and Spearmann's correlation tests as well as multivariate logistic regression analysis. Increased epithelial co-expression of COX-2 and PAR-2, as well as, elevated subepithelial density of tryptase-positive mast cells were found in AC as compared to normal lip (P<0.001). COX-2 overexpression was found to be a significant predictor of AC (P<0.034, forward stepwise, Wald), and to be correlated with both tryptase-positive mast cells and PAR-2 expression (P<0.01). The results suggest that epithelial COX-2 overexpression is a key event in AC, which is associated with increased tryptase-positive mast cells and PAR-2. Therefore, tryptase may contribute to COX-2 up-regulation by epithelial PAR-2 activation during early lip carcinogenesis.

Monte Carlo Study of the Fish-like Patterns of Anthracenes on Cu(111)

NASA Astrophysics Data System (ADS)

Kim, Kwangmoo; Einstein, T. L.; Sun, Dezheng; Kim, Dae-Ho; Bartels, Ludwig

2011-03-01

Using Monte Carlo calculations of the two-dimensional triangular lattice with a 2-component 3-state Potts model, we demonstrate a mechanism for the spontaneous formation of fish-like patterns of anthracene (AC) molecules on Cu(111) by sputtering and annealing, then cooling to ~ 80 K. The two components are an AC on a hollow site and another on a bridge site of Cu(111). The liquid crystal model with two separate parts, positional and orientational, only explains a part of the fish-like pattern, not the whole regular pattern. Our model fixes the positional order of AC's into the triangular lattice and the orientational order into three angles as observed in the experiments. The variation of the coverages of AC's is reflected in the change of the ratio of two components in our model. We also try to understand the compression of AC's with the introduction of Gaussian dispersion of AC's about their triangular lattice sites. Supported primarily by NSF Grants CHE 07-50334 with a secondary support from NSF-MRSEC at the University of Maryland, DMR05-20471. Work at UCR supported primarily by NSF CHE 07-49949.

Breath analyzer screening of emergency department patients suspected of alcohol intoxication.

PubMed

Sebbane, Mustapha; Claret, Pierre-Géraud; Jreige, Riad; Dumont, Richard; Lefebvre, Sophie; Rubenovitch, Josh; Mercier, Grégoire; Eledjam, Jean-Jacques; de la Coussaye, Jean-Emmanuel

2012-10-01

Acute alcohol intoxication is a frequent cause of emergency department (ED) visits. Evaluating a patient's alcohol intoxication is commonly based on both a physical examination and determination of blood alcohol concentration (BAC). To demonstrate the feasibility and usefulness of using a last-generation infrared breath analyzer as a non-invasive and rapid screening tool for alcohol intoxication in the ED. Adult patients suspected of acute alcohol intoxication were prospectively enrolled over 10 days. Breath alcohol concentrations (BrAC) were measured using a handheld infrared breath analyzer. BAC was determined simultaneously by automated enzymatic analysis of a venous blood sample. The relationship between BAC and BrAC values was examined by both linear regression and Bland-Altman analysis. The study included 54 patients (mean age 40±14 years, sex ratio M/F of 3/1). Breath and blood alcohol concentrations ranged from 0 to 1.44 mg/L and from 0 to 4.40 g/L (0-440 mg/dL), respectively. The mean individual BAC/BrAC ratio was 2615±387, 95% confidence interval 2509-2714, which is 30% higher than the legal ratio in France (2000). The correlation between both measurements was excellent: r=0.95 (0.92-0.97). Linear regression revealed BAC=0.026+1.29 (BrAC×2000) and BAC=0.026+0.99 (BrAC×2615). Mean BAC-BrAC differences and limits of agreement were 0.49 g/L [-0.35, 1.34] (or 49 mg/dL [-35, 134] and 0.01 g/L [-0.68, 0.71] (or 1 mg/dL [-68, 71]), for the 2000 and 2615 ratios, respectively. The calculated conversion coefficient provided a satisfactory determination of blood alcohol concentration. Breath alcohol testing, using appropriate BAC/BrAC conversion, different from the legal BAC/BrAC, could be a reliable alternative for routine screening and management of alcohol intoxication in the ED. Copyright © 2012 Elsevier Inc. All rights reserved.

Proteomics of the Autographa californica Nucleopolyhedrovirus Budded Virions ▿

PubMed Central

Wang, RanRan; Deng, Fei; Hou, Dianhai; Zhao, Yong; Guo, Lin; Wang, Hualin; Hu, Zhihong

2010-01-01

Baculoviruses produce two progeny phenotypes during their replication cycles. The occlusion-derived virus (ODV) is responsible for initiating primary infection in the larval midgut, and the budded virus (BV) phenotype is responsible for the secondary infection. The proteomics of several baculovirus ODVs have been revealed, but so far, no extensive analysis of BV-associated proteins has been conducted. In this study, the protein composition of the BV of Autographa californica nucleopolyhedrovirus (AcMNPV), the type species of baculoviruses, was analyzed by various mass spectrometry (MS) techniques, including liquid chromatography-triple quadrupole linear ion trap (LC-Qtrap), liquid chromatography-quadrupole time of flight (LC-Q-TOF), and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF). SDS-PAGE and MALDI-TOF analyses showed that the three most abundant proteins of the AcMNPV BV were GP64, VP39, and P6.9. A total of 34 viral proteins associated with the AcMNPV BV were identified by the indicated methods. Thirteen of these proteins, PP31, AC58/59, AC66, IAP-2, AC73, AC74, AC114, AC124, chitinase, polyhedron envelope protein (PEP), AC132, ODV-E18, and ODV-E56, were identified for the first time to be BV-associated proteins. Western blot analyses showed that ODV-E18 and ODV-E25, which were previously thought to be ODV-specific proteins, were also present in the envelop fraction of BV. In addition, 11 cellular proteins were found to be associated with the AcMNPV BV by both LC-Qtrap and LC-Q-TOF analyses. Interestingly, seven of these proteins were also identified in other enveloped viruses, suggesting that many enveloped viruses may commonly utilize certain conserved cellular pathways. PMID:20444894

Regulation of Split Linear Systems Over Rings: Coefficient-Assignment and Observers,

DTIC Science & Technology

1980-02-22

we give for the first time , a method to obtain an observer for a finite -free strongly observable The K-linear map irQ is defined as system 5" ( F. G...NAME a ADORESS~if dif!ttrent from Controlling Office) IS1 SECURITY CLASS . (of this report) SIS.. DE CL ASSI ’I CATION/ODOWNGRADING SCHEDULE 16...Entered) IEEE rRANSACTIONS ON AUTOMATIC CONTROL . VOL. Ac-27 . No. 1. FEaRUAay 1982 Regutlation of Split Linear Systems Over Rings: Coefficient

Electrostatic coalescence system with independent AC and DC hydrophilic electrodes

DOEpatents

Hovarongkura, A. David; Henry, Jr., Joseph D.

1981-01-01

An improved electrostatic coalescence system is provided in which independent AC and DC hydrophilic electrodes are employed to provide more complete dehydration of an oil emulsion. The AC field is produced between an AC electrode array and the water-oil interface wherein the AC electrode array is positioned parallel to the interface which acts as a grounded electrode. The emulsion is introduced into the AC field in an evenly distributed manner at the interface. The AC field promotes drop-drop and drop-interface coalescence of the water phase in the entering emulsion. The continuous oil phase passes upward through the perforated AC electrode array and enters a strong DC field produced between closely spaced DC electrodes in which small dispersed droplets of water entrained in the continuous phase are removed primarily by collection at hydrophilic DC electrodes. Large droplets of water collected by the electrodes migrate downward through the AC electrode array to the interface. All phase separation mechanisms are utilized to accomplish more complete phase separation.

Assessment of algorithms to identify patients with thrombophilia following venous thromboembolism.

PubMed

Delate, Thomas; Hsiao, Wendy; Kim, Benjamin; Witt, Daniel M; Meyer, Melissa R; Go, Alan S; Fang, Margaret C

2016-01-01

Routine testing for thrombophilia following venous thromboembolism (VTE) is controversial. The use of large datasets to study the clinical impact of thrombophilia testing on patterns of care and patient outcomes may enable more efficient analysis of this practice in a wide range of settings. We set out to examine how accurately algorithms using International Classification of Diseases 9th Revision (ICD-9) codes and/or pharmacy data reflect laboratory-confirmed thrombophilia diagnoses. A random sample of adult Kaiser Permanente Colorado patients diagnosed with unprovoked VTE between 1/2004 and 12/2010 underwent medical record abstraction of thrombophilia test results. Algorithms using "ICD-9" (positive if a thrombophilia ICD-9 code was present), "Extended anticoagulation (AC)" (positive if AC therapy duration was >6 months), and "ICD-9 & Extended AC" (positive for both) criteria to identify possible thrombophilia cases were tested. Using positive thrombophilia laboratory results as the gold standard, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value of each algorithm were calculated, along with 95% confidence intervals (CIs). In our cohort of 636 patients, sensitivities were low (<50%) for each algorithm. "ICD-9" yielded the highest PPV (41.5%, 95% CI 26.3-57.9%) and a high specificity (95.9%, 95% CI 94.0-97.4%). "Extended AC" had the highest sensitivity but lowest specificity, and "ICD-9 & Extended AC" had the highest specificity but lowest sensitivity. ICD-9 codes for thrombophilia are highly specific for laboratory-confirmed cases, but all algorithms had low sensitivities. Further development of methods to identify thrombophilia patients in large datasets is warranted. Copyright © 2015 Elsevier Ltd. All rights reserved.

Alternating current (AC) iontophoretic transport across human epidermal membrane: effects of AC frequency and amplitude.

PubMed

Yan, Guang; Xu, Qingfang; Anissimov, Yuri G; Hao, Jinsong; Higuchi, William I; Li, S Kevin

2008-03-01

As a continuing effort to understand the mechanisms of alternating current (AC) transdermal iontophoresis and the iontophoretic transport pathways in the stratum corneum (SC), the objectives of the present study were to determine the interplay of AC frequency, AC voltage, and iontophoretic transport of ionic and neutral permeants across human epidermal membrane (HEM) and use AC as a means to characterize the transport pathways. Constant AC voltage iontophoresis experiments were conducted with HEM in 0.10 M tetraethyl ammonium pivalate (TEAP). AC frequencies ranging from 0.0001 to 25 Hz and AC applied voltages of 0.5 and 2.5 V were investigated. Tetraethyl ammonium (TEA) and arabinose (ARA) were the ionic and neutral model permeants, respectively. In data analysis, the logarithm of the permeability coefficients of HEM for the model permeants was plotted against the logarithm of the HEM electrical resistance for each AC condition. As expected, linear correlations between the logarithms of permeability coefficients and the logarithms of resistances of HEM were observed, and the permeability data were first normalized and then compared at the same HEM electrical resistance using these correlations. Transport enhancement of the ionic permeant was significantly larger than that of the neutral permeant during AC iontophoresis. The fluxes of the ionic permeant during AC iontophoresis of 2.5 V in the frequency range from 5 to 1,000 Hz were relatively constant and were approximately 4 times over those of passive transport. When the AC frequency decreased from 5 to 0.001 Hz at 2.5 V, flux enhancement increased to around 50 times over passive transport. While the AC frequency for achieving the full effect of iontophoretic enhancement at low AC frequency was lower than anticipated, the frequency for approaching passive diffusion transport at high frequency was higher than expected from the HEM morphology. These observations are consistent with a transport model of multiple barriers in series and the previous hypothesis that the iontophoresis pathways across HEM under AC behave like a series of reservoirs interconnected by short pore pathways.

Comparing the TYCHO Catalogue with CCD Astrograph Observations

NASA Astrophysics Data System (ADS)

Zacharias, N.; Hoeg, E.; Urban, S. E.; Corbin, T. E.

1997-08-01

Selected fields around radio-optical reference frame sources have been observed with the U.S. Naval Observatory CCD astrograph (UCA). This telescope is equipped with a red-corrected 206mm 5-element lens and a 4k by 4k CCD camera which provides a 1 square degree field of view. Positions with internal precisions of 20 mas for stars in the 7 to 12 magnitude range have been obtained with 30 second exposures. A comparison is made with the Tycho Catalogue, which is accurate to about 5 to 50 mas at mean epoch of J1991.25, depending on the magnitude of the star. Preliminary proper motions are obtained using the Astrographic Catalogue (AC) to update the Tycho positions to the epoch of the UCA observations, which adds an error contribution of about 15 to 20 mas. Individual CCD frames have been reduced with an average of 30 Tycho reference stars per frame. A linear plate model gives an average adjustment standard error of 46 mas, consistent with the internal errors. The UCA is capable of significantly improving the positions of Tycho stars fainter than about visual magnitude 9.5.

A new infusion pathway monitoring system utilizing electrostatic induced potential.

PubMed

Maki, Hiromichi; Yonezawa, Yoshiharu; Ogawa, Hidekuni; Ninomiya, Ishio; Sada, Kouji; Hamada, Shingo; Hahn, Alien W; Caldwell, W Morton

2006-01-01

We have developed a new infusion pathway monitoring system employing linear integrated circuits and a low-power 8-bit single chip microcomputer. The system is available for hospital and home use and it constantly monitors the intactness of the pathway. The sensor is an electro-conductive polymer electrode wrapped around the infusion polyvinyl chloride infusion tube. This records an AC (alternating current) voltage induced on the patient's body by electrostatic coupling from the normal 100 volt, 60 Hz AC power line wiring field in the patient's room. If the injection needle or infusion tube becomes detached, then the system detects changes in the induced AC voltage and alerts the nursing station, via the nurse call system or PHS (personal handy phone System).

Prothymosin-α and parathymosin expression predicts poor prognosis in squamous and adenosquamous carcinomas of the gallbladder

PubMed Central

Chen, Kang; Xiong, Li; Yang, Zhuling; Huang, Shengfu; Zeng, Rong; Miao, Xiongying

2018-01-01

The present study aimed to investigate the expression patterns of prothymosin-α (PTMA) and parathymosin (PTMS) in patients with squamous cell carcinoma (SCC), adenosquamous cell carcinoma (ASC) and adenocarcinoma (AC) of the gallbladder, and to assess their association with the clinicopathological characteristics and prognosis of the patients. A retrospective analysis of data pertaining to patients with SCC/ASC (n=46) and AC (n=80) of the gallbladder, who were treated with surgical resection, was conducted. Kaplan-Meier survival analysis was also performed to assess the correlation of the expression pattern with survival. The results revealed a higher percentage of patients with a large tumor diameter (>3 cm) in the SCC/ASC group as compared with those in the AC group (P<0.05). No significant differences were observed between patients with SCC/ASC and those with AC with respect to the patient sex, presence of gallstones, TNM stage, lymph node metastasis, invasive growth into anatomically contiguous structures, surgical methods used, survival rate, and the expression levels of PTMA and PTMA (P>0.05). However, positive expression of PTMA and PTMA was associated with tumor size, TNM stage, lymph node metastasis, locally invasive growth, and treatment with radical resection in patients with SCC/ASC and AC (P<0.05). In addition, positive expression of PTMA and PTMA was observed in a significantly lower number of patients with advanced AC as compared with those in early AC (P<0.05), while these expression levels were also associated with shorter survival in the SCC/ASC group and AC group (P<0.05). Cox multivariate analysis also demonstrated a negative correlation between PTMA and PTMA levels, and the postoperative survival rate in the two groups. In conclusion, the present study indicated that the expression levels of PTMA and PTMA were closely associated with the tumorigenesis and progression of SCC, ASC and AC of the gallbladder. Positive expression of PTMA and PTMA may serve as a valuable prognostic factor in these patients. PMID:29541218

Effect of DOTA position on melanoma targeting and pharmacokinetic properties of 111In-labeled lactam bridge-cyclized alpha-melanocyte stimulating hormone peptide.

PubMed

Guo, Haixun; Yang, Jianquan; Gallazzi, Fabio; Prossnitz, Eric R; Sklar, Larry A; Miao, Yubin

2009-11-01

The purpose of this study was to examine the effect of DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) position on melanoma targeting and pharmacokinetics of radiolabeled lactam bridge-cyclized alpha-melanocyte stimulating hormone (alpha-MSH) peptide. A novel lactam bridge-cyclized alpha-MSH peptide, Ac-GluGlu-CycMSH[DOTA] {Ac-Glu-Glu-c[Lys-Nle-Glu-His-DPhe-Arg-Trp-Gly-Arg-Pro-Val-Lys(DOTA)]}, was synthesized using standard 9-fluorenylmethyloxycarbonyl (Fmoc) chemistry. DOTA was directly attached to the alpha-amino group of Lys in the cyclic ring, while the N-terminus of the peptide was acetylated to generate Ac-GluGlu-CycMSH[DOTA]. The MC1 receptor binding affinity of Ac-GluGlu-CycMSH[DOTA] was determined in B16/F1 melanoma cells. Melanoma targeting and pharmacokinetic properties of Ac-GluGlu-CycMSH[DOTA]-111In were determined in B16/F1 melanoma-bearing C57 mice and compared to that of 111In-DOTA-Gly-Glu-c[Lys-Nle-Glu-His-DPhe-Arg-Trp-Gly-Arg-Pro-Val-Asp] (111In-DOTA-GlyGlu-CycMSH; DOTA was coupled to the N-terminus of the peptide). Ac-GluGlu-CycMSH[DOTA] displayed 0.6 nM MC1 receptor binding affinity in B16/F1 cells. Ac-GluGlu-CycMSH[DOTA]-111In was readily prepared with greater than 95% radiolabeling yield. Ac-GluGlu-CycMSH[DOTA]-111In exhibited high tumor uptake (11.42 +/- 2.20% ID/g 2 h postinjection) and prolonged tumor retention (9.42 +/- 2.41% ID/g 4 h postinjection) in B16/F1 melanoma-bearing C57 mice. The uptake values for nontarget organs were generally low (<1.3% ID/g) except for the kidneys 2, 4, and 24 h postinjection. DOTA position exhibited profound effect on melanoma targeting and pharmacokinetic properties of Ac-GluGlu-CycMSH[DOTA]-111In, providing a new insight into the design of lactam bridge-cyclized peptide for melanoma imaging and therapy.

Discovery of melanocortin ligands via a double simultaneous substitution strategy based on the Ac-His-DPhe-Arg-Trp-NH2 template.

PubMed

Todorovic, Aleksandar; Lensing, Cody J; Holder, Jerry Ryan; Scott, Joseph W; Sorensen, Nicholas B; Haskell-Luevano, Carrie

2018-05-21

The melanocortin system regulates an array of diverse physiological functions including pigmentation, feeding behavior, energy homeostasis, cardiovascular regulation, sexual function, and steroidogenesis. Endogenous melanocortin agonist ligands all possess the minimal messaging tetrapeptide sequence His-Phe-Arg-Trp. Based on this endogenous sequence, the Ac-His1-DPhe2-Arg3-Trp4-NH 2 tetrapeptide has previously been shown to be a useful scaffold when utilizing traditional positional scanning approaches to modify activity at the various melanocortin receptors (MC1-5R). The study reported herein was undertaken to evaluate a double simultaneous substitution strategy as an approach to further diversify the Ac-His1-DPhe2-Arg3-Trp4-NH 2 tetrapeptide with concurrent introduction of natural and unnatural amino acids at positions 1, 2, or 4 as well as an octanoyl residue at the N-terminus. The designed library includes the following combinations: (A) double simultaneous substitution at capping group position (Ac) together with position 1, 2, or 4, (B) double simultaneous substitution at position 1 and 2, (C) double simultaneous substitution at position 1 and 4, and (D) double simultaneous substitution at position 2 and 4. Several lead ligands with unique pharmacologies were discovered in the current study including antagonists targeting the neuronal mMC3R with minimal agonist activity and ligands with selective profiles for the various melanocortin subtypes. The results suggest that the double simultaneous substitution strategy is a suitable approach in altering melanocortin receptor potency, selectivity, or converting agonists into antagonists and vice versa.

Help Desk Answers: Surgery vs conservative management for AC joint repair: How do the 2 compare?

PubMed

Matchin, Bruce; Yee, Bruce; Mott, Timothy

2016-04-01

When not considering the grade of acromioclavicular (AC) joint dislocation, both conservative and surgical management lead to positive outcomes, although surgically managed patients require more time out of work.

Application of novel Ni(II) complex and ZrO2 nanoparticle as mediators for electrocatalytic determination of N-acetylcysteine in drug samples.

PubMed

Karimi-Maleh, Hassan; Salehi, Mehdi; Faghani, Fatemeh

2017-10-01

The electrooxidation of N-acetylcysteine (N-AC) was studied by a novel Ni(II) complex modified ZrO 2 nanoparticle carbon paste electrode [Ni(II)/ZrO 2 /NPs/CPE] using voltammetric methods. The results showed that Ni(II)/ZrO 2 /NPs/CPE had high electrocatalytic activity for the electrooxidation of N-AC in aqueous buffer solution (pH = 7.0). The electrocatalytic oxidation peak currents increase linearly with N-AC concentrations over the concentration ranges of 0.05-600μM using square wave voltammetric methods. The detection limit for N-AC was equal to 0.009μM. The catalytic reaction rate constant, k h , was calculated (7.01 × 10 2  M -1  s -1 ) using the chronoamperometry method. Finally, Ni(II)/ZrO 2 /NPs/CPE was also examined as an ultrasensitive electrochemical sensor for the determination of N-AC in real samples such as tablet and urine. Copyright © 2017. Published by Elsevier B.V.

Charging in the ac Conductance of a Double Barrier Resonant Tunneling Structure

NASA Technical Reports Server (NTRS)

Anantram, M. P.; Saini, Subhash (Technical Monitor)

1998-01-01

There have been many studies of the linear response ac conductance of a double barrier resonant tunneling structure (DBRTS), both at zero and finite dc biases. While these studies are important, they fail to self consistently include the effect of the time dependent charge density in the well. In this paper, we calculate the ac conductance at both zero and finite do biases by including the effect of the time dependent charge density in the well in a self consistent manner. The charge density in the well contributes to both the flow of displacement currents in the contacts and the time dependent potential in the well. We find that including these effects can make a significant difference to the ac conductance and the total ac current is not equal to the simple average of the non-selfconsistently calculated conduction currents in the two contacts. This is illustrated by comparing the results obtained with and without the effect of the time dependent charge density included correctly. Some possible experimental scenarios to observe these effects are suggested.

Lateral separation of colloids or cells by dielectrophoresis augmented by AC electroosmosis.

PubMed

Zhou, Hao; White, Lee R; Tilton, Robert D

2005-05-01

Colloidal particles and biological cells are patterned and separated laterally adjacent to a micropatterned electrode array by applying AC electric fields that are principally oriented normally to the electrode array. This is demonstrated for yeast cells, red blood cells, and colloidal polystyrene particles of different sizes and zeta-potentials. The separation mechanism is observed experimentally to depend on the applied field frequency and voltage. At high frequencies, particles position themselves in a manner that is consistent with dielectrophoresis, while at low frequencies, the positioning is explained in terms of a strong coupling between gravity, the vertical component of the dielectrophoretic force, and the Stokes drag on particles induced by AC electroosmotic flow. Compared to high frequency dielectrophoretic separations, the low frequency separations are faster and require lower applied voltages. Furthermore, the AC electroosmosis coupling with dielectrophoresis may enable cell separations that are not feasible based on dielectrophoresis alone.

Comparison of Doxorubicin and Cyclophosphamide Versus Single-Agent Paclitaxel As Adjuvant Therapy for Breast Cancer in Women With 0 to 3 Positive Axillary Nodes: CALGB 40101 (Alliance)

PubMed Central

Shulman, Lawrence N.; Berry, Donald A.; Cirrincione, Constance T.; Becker, Heather P.; Perez, Edith A.; O'Regan, Ruth; Martino, Silvana; Shapiro, Charles L.; Schneider, Charles J.; Kimmick, Gretchen; Burstein, Harold J.; Norton, Larry; Muss, Hyman; Hudis, Clifford A.; Winer, Eric P.

2014-01-01

Purpose Optimal adjuvant chemotherapy for early-stage breast cancer balances efficacy and toxicity. We sought to determine whether single-agent paclitaxel (T) was inferior to doxorubicin and cyclophosphamide (AC), when each was administered for four or six cycles of therapy, and whether it offered less toxicity. Patients and Methods Patients with operable breast cancer with 0 to 3 positive nodes were enrolled onto the study to address the noninferiority of single-agent T to AC, defined as the one-sided 95% upper-bound CI (UCB) of hazard ratio (HR) of T versus AC less than 1.30 for the primary end point of relapse-free survival (RFS). As a 2 × 2 factorial design, duration of therapy was also addressed and was previously reported. Results With 3,871 patients enrolled onto the trial, a median follow-up period of 6.1 years, and 437 RFS events, we achieved an HR of 1.26 (one sided 95% UCB, 1.48; favoring AC does not allow a conclusion of noninferiority of T with AC; UCB > 1.3). With 266 patient deaths, the HR for overall survival (OS) was 1.27 favoring AC (UCB, 1.56). The estimated absolute advantage of AC at 5 years is 3% for RFS (91 v 88%) and 1% for OS (95 v 94%). All nine treatment-related deaths were patients receiving AC and are included in the analyses of both RFS and OS. Hematologic toxicity was more common in patients treated with AC, and neuropathy was more common in patients treated with T. Conclusion This trial did not show noninferiority of T to AC, a conclusion that is unlikely to change with additional events and follow-up. T was less toxic than AC. PMID:24934787

A double signal amplification platform for ultrasensitive and simultaneous detection of ascorbic acid, dopamine, uric acid and acetaminophen based on a nanocomposite of ferrocene thiolate stabilized Fe₃O₄@Au nanoparticles with graphene sheet.

PubMed

Liu, Meiling; Chen, Qiong; Lai, Cailang; Zhang, Youyu; Deng, Jianhui; Li, Haitao; Yao, Shouzhuo

2013-10-15

A double signal amplification platform for ultrasensitive and simultaneous detection of ascorbic acid (AA), dopamine (DA), uric acid (UA) and acetaminophen (AC) was fabricated by a nanocomposite of ferrocene thiolate stabilized Fe₃O₄@Au nanoparticles with graphene sheet. The platform was constructed by coating a newly synthesized phenylethynyl ferrocene thiolate (Fc-SAc) modified Fe₃O₄@Au NPs coupling with graphene sheet/chitosan (GS-chitosan) on a glassy carbon electrode (GCE) surface. The Fe₃O₄@Au-S-Fc/GS-chitosan modified GCE exhibits a synergistic catalytic and amplification effect toward AA, DA, UA and AC oxidation. The oxidation peak currents of the four compounds on the electrode were linearly dependent on AA, DA, UA and AC concentrations in the ranges of 4-400 μM, 0.5-50 μM, 1-300 μM and 0.3-250 μM in the individual detection of each component, respectively. By simultaneously changing the concentrations of AA, DA, UA and AC, their electrochemical oxidation peaks appeared at -0.03, 0.15, 0.24 and 0.35 V, and good linear current responses were obtained in the concentration ranges of 6-350, 0.5-50, 1-90 and 0.4-32 μM with the detection limits of 1, 0.1, 0.2 and 0.05 μM (S/N=3), respectively. Copyright © 2013 Elsevier B.V. All rights reserved.

Life Cycle of Midlatitude Deep Convective Systems in a Lagrangian Framework

NASA Technical Reports Server (NTRS)

Feng, Zhe; Dong, Xiquan; Xie, Baike; McFarlane, Sally A.; Kennedy, Aaron; Lin, Bing; Minnis, Patrick

2012-01-01

Deep Convective Systems (DCSs) consist of intense convective cores (CC), large stratiform rain (SR) regions, and extensive non-precipitating anvil clouds (AC). This study focuses on the evolution of these three components and the factors that affect convective AC production. An automated satellite tracking method is used in conjunction with a recently developed multi-sensor hybrid classification to analyze the evolution of DCS structure in a Lagrangian framework over the central United States. Composite analysis from 4221 tracked DCSs during two warm seasons (May-August, 2010-2011) shows that maximum system size correlates with lifetime, and longer-lived DCSs have more extensive SR and AC. Maximum SR and AC area lag behind peak convective intensity and the lag increases linearly from approximately 1-hour for short-lived systems to more than 3-hours for long-lived ones. The increased lag, which depends on the convective environment, suggests that changes in the overall diabatic heating structure associated with the transition from CC to SR and AC could prolong the system lifetime by sustaining stratiform cloud development. Longer-lasting systems are associated with up to 60% higher mid-tropospheric relative humidity and up to 40% stronger middle to upper tropospheric wind shear. Regression analysis shows that the areal coverage of thick AC is strongly correlated with the size of CC, updraft strength, and SR area. Ambient upper tropospheric wind speed and wind shear also play an important role for convective AC production where for systems with large AC (radius greater than 120-km) they are 24% and 20% higher, respectively, than those with small AC (radius=20 km).

Colorimetric anion sensors based on positional effect of nitro group for recognition of biologically relevant anions in organic and aqueous medium, insight real-life application and DFT studies

NASA Astrophysics Data System (ADS)

Singh, Archana; Sahoo, Suban K.; Trivedi, Darshak R.

2018-01-01

A new six colorimetric receptors A1-A6 were designed and synthesized, characterized by typical common spectroscopic techniques like FT-IR, UV-Visible, 1H NMR, 13C NMR and ESI-MS. The receptor A1 and A2 exhibit a significant naked-eye response towards F- and AcO- ions in DMSO. Due to presences of the NO2 group at para and ortho position with extended π-conjugation of naphthyl group carrying sbnd OH as a binding site. Compared to receptor A2, A1 is extremely capable of detecting F- and AcO- ions present in the form of sodium salts in an aqueous medium. This is owed to the occurrence of sbnd NO2 group at para position induced in increasing the acidity of sbnd OH proton. Consequently, it easily gets deprotonated in aqueous media. The detection limit of receptor A1 was turned out to be 0.40 and 0.35 ppm for F- and AcO- ions which is beneath WHO permission level (1.0 ppm). Receptor A1 shows a solitary property of solvatochromism in different aprotic solvents in presence of AcO- ion. Receptor A1 depicts high selectivity towards AcO- ion in DMSO: HEPES buffer (9:1, v/v). Receptor A1 proved itself for real life application by detecting anion in solution and solid state. The binding mechanism of receptor A1 with AcO- and F- ions was monitored from 1HNMR titration and DFT study.

Nutritional status of patients with locally advanced pancreatic cancer: a pilot study.

PubMed

Ferrucci, Leah M; Bell, Diana; Thornton, Jennifer; Black, Glenda; McCorkle, Ruth; Heimburger, Douglas C; Saif, Muhammad Wasif

2011-11-01

Nutritional status may influence quality of life and prognosis among pancreatic cancer patients, yet few studies describe measures of nutritional status during treatment. We evaluated the nutritional status of locally advanced pancreatic cancer (LAPC) patients undergoing chemoradiotherapy who received baseline nutritional assessment and counseling. Fourteen newly diagnosed LAPC patients enrolled in phase I/II trials of capecitabine with concomitant radiotherapy were assessed for baseline clinical nutrition measures (body mass index, albumin, weight loss, total energy, and protein intake). Participants completed the Anorexia/Cachexia Subscale (A/CS) questionnaire at baseline and during the 6 weeks of treatment. We evaluated associations between baseline characteristics and subsequent A/CS scores with linear regression and changes in A/CS were assessed with the paired t test. We observed a statistically significant increase in mean A/CS between baseline [24.9, standard deviation (SD) = 9.7] and end of treatment (29.9, SD = 6.2). Controlling for baseline A/CS score, only weight loss greater than 5% of body weight over 1 month was associated with A/CS scores at 6 weeks (β = 10.558, standard error = 3.307, p value = 0.009) and mean A/CS scores during the last 3 weeks of treatment (β = 12.739, standard error = 2.251, p value = 0.001). After 6 weeks of chemoradiotherapy, LAPC patients reported a statistically significant improvement in appetite and weight concerns. Increases in AC/S scores were associated with higher baseline A/CS scores and weight loss of 5% or more during 1 month. Further research is needed to determine the impact of nutritional support during treatment, as improvements in this domain may impact LAPC patients' overall quality of life.

Highly sensitive glucose sensor based on monodisperse palladium nickel/activated carbon nanocomposites.

PubMed

Koskun, Yağmur; Şavk, Aysun; Şen, Betül; Şen, Fatih

2018-06-20

Glucose enzyme biosensors have been used for a variety of applications such as medical diagnosis, bioprocess engineering, beverage industry and environmental scanning etc. and there is still a growing interest in glucose sensors. For this purpose, addressed herein, as a novel glucose sensor, highly sensitive activated carbon (AC) decorated monodisperse nickel and palladium alloy nanocomposites modified glassy carbon electrode (Ni-Pd@AC/GCE NCs) have been synthesized by in-situ reduction technique. Raman Spectroscopy (RS), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), cyclic voltammetry (CV) and chronoamperometry (CA) were used for the characterization of the prepared non-enzymatic glucose sensor. The characteristic sensor properties of the Ni-Pd@AC/GCE electrode were compared with Ni-Pd NCs/GCE, Ni@AC/GCE and Pd@AC/GCE and the results demonstrate that the AC is very effective in the enhancement of the electrocatalytic properties of sensor. In addition, the Ni-Pd@AC/GCE nanocomposites showed a very low detection limit of 0.014 μM, a wide linear range of 0.01 mM-1 mM and a very high sensitivity of 90 mA mM -1  cm -2 . Furthermore, the recommended sensor offer the various advantageous such as facile preparation, fast response time, high selectivity and sensitivity. Lastly, monodisperse Ni-Pd@AC/GCE was utilized to detect glucose in real sample species. Copyright © 2018 Elsevier B.V. All rights reserved.

Variation of antibiotic consumption and its correlated factors in Turkey.

PubMed

Sahin, Ayfer; Akici, Ahmet; Aydin, Volkan; Melik, Bahar; Aksoy, Mesil; Alkan, Ali

2017-07-01

Presentation of antibiotic utilization data by reliable and comparable analyses constitutes an important way of ensuring rational use of antibiotics. This study aimed to evaluate antibiotic consumption (AC) of Turkey by each city/region and to investigate any association of such consumption with socio-economic factors. For 81 provinces and 12 regions in Turkey, AC data from IMS (Intercontinental Medical Statistics) in 2011 was analyzed in accordance with "ATC/DDD, DID" (Anatomical Therapeutic Chemical/Defined Daily Doses, DID = DDD/1000 inhabitants/day) methodology supported by World Health Organization. Association between provincial AC rates and socio-economic development index (SEDI)-2011 and between regional AC rates and some health indicators were analyzed. While provincial AC data of Turkey was detected to vary between 17.2 and 55.2 DID (Hakkari and Usak, respectively), regional AC ranged from 28.4 to 48.9 DID (Middle Eastern Anatolia and Western Anatolia, respectively). Mostly consumed antibiotic group among all regions were beta-lactamase inhibitor/penicillin combinations (range: 9.9-17.6 DID). SEDI and AC of each city showed positive correlation (rho = 0.683, p < 0.001). While regional AC was positively associated with percentage of 14-year-old population (p = 0.002) and pharmacist density (p < 0.001), it was negatively associated with physician density (p = 0.038). It is remarkable that Turkey, at both provincial and regional levels, exhibits important variations in AC, which is proportional to socio-economic status. Besides, the consumption is found to be closely associated with recognized critical factors of access to healthcare. These findings are expected to provide important insights to the activities promoting rational use of antibiotics.

Baerveldt drainage tube motility in the anterior chamber.

PubMed

Tan, Annelie N; De Witte, Pauline M; Webers, Carroll A B; Berendschot, Tos T J M; De Brabander, John; Schouten, Johannes S A G; Beckers, Henny J M

2014-01-01

To investigate the stability in position of the Baerveldt glaucoma drainage tube over time and to study movement of the drainage tube in the anterior chamber (AC) under varying light conditions. This prospective study included 70 eyes with implantation of a Baerveldt glaucoma drainage tube in the anterior chamber. Anterior segment optical coherence tomography (AS-OCT) images were made preoperatively to quantify AC depth. AS-OCT images were made twice under photopic and twice under scotopic conditions, in the angle parallel to the Baerveldt tube to quantify drainage tube position, at 3, 6, 12, and 24 months postoperatively. Tube-corneal (T-C) and tube-iris (T-I) distances were measured. Additionally, the central AC depth and the peripheral angle opening (AOD 500) were determined. Two subgroups were distinguished according to tube position: free in the AC (group 1, n = 48) and transiridal (group 2, n = 22). After 24 months of follow-up, the drainage tube was found to move statistically significantly closer (0.12 mm) to the corneal endothelium in group 1 (p<0.01). There was no statistically significant difference in T-C distance over time in group 2. The T-C distance did not differ under photopic versus scotopic circumstances (p = 0.32). In both groups, the T-I distance was larger under scotopic conditions, a result of pupil dilation. The Baerveldt glaucoma drainage tube remained in a stable position when a transiridal implantation was performed, whereas the tube moved closer to the endothelium when placed free into the AC. Transiridal implantation of the Baerveldt tube seems a safe alternative for tube implantation with respect to tube motility.

21-Gene Recurrence Score for prognosis and prediction of taxane benefit after adjuvant chemotherapy plus endocrine therapy: results from NSABP B-28/NRG Oncology.

PubMed

Mamounas, Eleftherios P; Tang, Gong; Paik, Soonmyung; Baehner, Frederick L; Liu, Qing; Jeong, Jong-Hyeon; Kim, S Rim; Butler, Steven M; Jamshidian, Farid; Cherbavaz, Diana B; Sing, Amy P; Shak, Steven; Julian, Thomas B; Lembersky, Barry C; Wickerham, D Lawrence; Costantino, Joseph P; Wolmark, Norman

2018-02-01

The 21-gene recurrence score (RS) predicts outcome and benefit from adjuvant chemotherapy benefit in breast cancer patients treated with adjuvant endocrine therapy. In the NSABP B-28 study, we evaluated the 21-gene RS for its prognostic impact and its ability to predict benefit from paclitaxel (P) in node-positive, estrogen receptor-positive (ER+) breast cancer patients treated with adjuvant chemotherapy plus tamoxifen. The B-28 trial compared doxorubicin/cyclophosphamide (AC) with AC followed by P in 3060 patients. Tamoxifen for 5 years was also given to patients > 50 years and those < 50 years with ER+ and/or progesterone receptor-positive (PR+) tumors. The present study includes 1065 ER-positive, tamoxifen-treated patients with RS assessment. Median follow-up time was 11.2 years. In univariate analyses, RS was a significant predictor of outcome. In multivariate analyses, RS remained a significant independent predictor of outcome beyond clinico-pathologic factors, age, and type of surgery (p < 0.001). In the study population (n = 1065), the disease-free survival (DFS) hazard ratio (HR) with adding P to AC was 0.87 (95% CI 0.72-1.05; p = 0.14). RS was not a significant predictor of P benefit: for DFS, HRs for adding P to AC in RS low, intermediate, and high subgroups were 1.01 (95% CI 0.69-1.47; p = 0.99), 0.84 (95% CI 0.62-1.14; p = 0.26), and 0.81 (95% CI 0.60-1.10; p = 0.21), respectively (interaction p = 0.64). Similar findings were observed for the other study endpoints. RS maintains significant prognostic impact in ER-positive, node-positive patients treated with adjuvant chemotherapy plus tamoxifen. However, RS did not significantly predict benefit from adding paclitaxel to AC chemotherapy. (Trial Registration: PDQ: NSABP-B-28).

Comparative methods to assess harmonic response of nonlinear piezoelectric energy harvesters interfaced with AC and DC circuits

NASA Astrophysics Data System (ADS)

Lan, Chunbo; Tang, Lihua; Harne, Ryan L.

2018-05-01

Nonlinear piezoelectric energy harvester (PEH) has been widely investigated during the past few years. Among the majority of these researches, a pure resistive load is used to evaluate power output. To power conventional electronics in practical application, the alternating current (AC) generated by nonlinear PEH needs to be transformed into a direct current (DC) and rectifying circuits are required to interface the device and electronic load. This paper aims at exploring the critical influences of AC and DC interface circuits on nonlinear PEH. As a representative nonlinear PEH, we fabricate and evaluate a monostable PEH in terms of generated power and useful operating bandwidth when it is connected to AC and DC interface circuits. Firstly, the harmonic balance analysis and equivalent circuit representation method are utilized to tackle the modeling of nonlinear energy harvesters connected to AC and DC interface circuits. The performances of the monostable PEH connected to these interface circuits are then analyzed and compared, focusing on the influences of the varying load, excitation and electromechanical coupling strength on the nonlinear dynamics, bandwidth and harvested power. Subsequently, the behaviors of the monostable PEH with AC and DC interface circuits are verified by experiment. Results indicate that both AC and DC interface circuits have a peculiar influence on the power peak shifting and operational bandwidth of the monostable PEH, which is quite different from that on the linear PEH.

Linear ketenimines. Variable structures of C,C-dicyanoketenimines and C,C-bis-sulfonylketenimines.

PubMed

Finnerty, Justin; Mitschke, Ullrich; Wentrup, Curt

2002-02-22

C,C-dicyanoketenimines 10a-c were generated by flash vacuum thermolysis of ketene N,S-acetals 9a-c or by thermal or photochemical decomposition of alpha-azido-beta-cyanocinnamonitrile 11. In the latter reaction, 3,3-dicyano-2-phenyl-1-azirine 12 is also formed. IR spectroscopy of the keteniminines isolated in Ar matrixes or as neat films, NMR spectroscopy of 10c, and theoretical calculations (B3LYP/6-31G) demonstrate that these ketenimines have variable geometry, being essentially linear along the CCN-R framework in polar media (neat films and solution), but in the gas phase or Ar matrix they are bent, as is usual for ketenimines. Experiments and calculations agree that a single CN substituent as in 13 is not enough to enforce linearity, and sulfonyl groups are less effective that cyano groups in causing linearity. C,C-bis(methylsulfonyl)ketenimines 4-5 and a C-cyano-C-(methylsulfonyl)ketenimine 15 are not linear. The compound p-O2NC6H4N=C=C(COOMe)2 previously reported in the literature is probably somewhat linearized along the CCNR moiety. A computational survey (B3LYP/6-31G) of the inversion barrier at nitrogen indicates that electronegative C-substituents dramatically lower the barrier; this is also true of N-acyl substituents. Increasing polarity causes lower barriers. Although N-alkylbis(methylsulfonyl)ketenimines are not calculated to be linear, the barriers are so low that crystal lattice forces can induce planarity in N-methylbis(methylsulfonyl)ketenimine 3.

Identification of ATP Citrate Lyase as a Positive Regulator of Glycolytic Function in Glioblastomas

PubMed Central

Beckner, Marie E.; Fellows-Mayle, Wendy; Zhang, Zhe; Agostino, Naomi R.; Kant, Jeffrey A.; Day, Billy W.; Pollack, Ian F.

2009-01-01

Glioblastomas, the most malignant type of glioma, are more glycolytic than normal brain tissue. Robust migration of glioblastoma cells has been previously demonstrated under glycolytic conditions and their pseudopodia contain increased glycolytic and decreased mitochondrial enzymes. Glycolysis is suppressed by metabolic acids, including citric acid which is excluded from mitochondria during hypoxia. We postulated that glioma cells maintain glycolysis by regulating metabolic acids, especially in their pseudopodia. The enzyme that breaks down cytosolic citric acid is ATP citrate lyase (ACLY). Our identification of increased ACLY in pseudopodia of U87 glioblastoma cells on 1D gels and immunoblots prompted investigation of ACLY gene expression in gliomas for survival data and correlation with expression of ENO1, that encodes enolase 1. Queries of the NIH’s REMBRANDT brain tumor database based on Affymetrix data indicated that decreased survival correlated with increased gene expression of ACLY in gliomas. Queries of gliomas and glioblastomas found an association of upregulated ACLY and ENO1 expression by chi square for all probe sets (reporters) combined and correlation for numbers of probe sets indicating shared upregulation of these genes. Real-time quantitative PCR confirmed correlation between ACLY and ENO1 in 21 glioblastomas (p < 0.001). Inhibition of ACLY with hydroxycitrate suppressed (p < 0.05) in vitro glioblastoma cell migration, clonogenicity and brain invasion under glycolytic conditions and enhanced the suppressive effects of a Met inhibitor on cell migration. In summary, gene expression data, proteomics and functional assays support ACLY as a positive regulator of glycolysis in glioblastomas. PMID:19795461

AC conductivity and Dielectric Study of Chalcogenide Glasses of Se-Te-Ge System

NASA Astrophysics Data System (ADS)

Salman, Fathy

2004-01-01

The ac conductivity and dielectric properties of glassy system SexTe79 - xGe21, with x = 11, 14, 17 at.%, has been studied at temperatures 300 to 450 K and over a wide range of frequencies (50 Hz to 500 kHz). Experimental results indicate that the ac conductivity and the dielectric constants depend on temperature, frequency and Se content. The conductivity as a function of frequency exhibited two components: dc conductivity s dc, and ac conductivity s ac, where s ac ˜ w s. The mechanism of ac conductivity can be reasonably interpreted in terms of the correlated barrier hopping model (CBH). The activation energies are estimated and discussed. The dependence of ac conductivity and dielectric constants on the Se content x can be interpreted as the effect of Se fraction on the positional disorder. The impedance plot at each temperature appeared as a semicircle passes through the origin. Each semicircle is represented by an equivalent circuit of parallel resistance Rb and capacitance Cb.

(In)sensitivity of GNSS techniques to geocenter motion

NASA Astrophysics Data System (ADS)

Rebischung, Paul; Altamimi, Zuheir; Springer, Tim

2013-04-01

As a satellite-based technique, GNSS should be sensitive to motions of the Earth's center of mass (CM) with respect to the Earth's crust. In theory, the weekly solutions of the IGS Analysis Centers (ACs) should indeed have the "instantaneous" CM as their origin, and the net translations between the weekly AC frames and a secular frame such as ITRF2008 should thus approximate the non-linear motion of CM with respect to the Earth's center of figure. However, the comparison of the AC translation time series with each other, with SLR geocenter estimates or with geophysical models reveals that this way of observing geocenter motion with GNSS currently gives unreliable results. The fact that the origin of the weekly AC solutions shoud be CM stems from the satellite equations of motion, in which no degree-1 Stokes coefficients are included. It is therefore reasonable to think that any mis-modeling or uncertainty about the forces acting on GNSS satellites can potentially offset the network origin from CM. That is why defects in radiation pressure modeling have long been assumed to be the main origin of the GNSS geocenter errors. In particular, Meindl et al. (2012) incriminate the correlation between the Z component of the origin and the direct radiation pressure parameters D0. We review here the sensitivity of GNSS techniques to geocenter motion from a different perspective. Our approach consists in determining the signature of a geocenter error on GNSS observations, and seeing how and how well such an error can be compensated by all other usual GNSS parameters. (In other words, we look for the linear combinations of parameters which have the maximal partial correlations with each of the 3 components of the origin, and evaluate these maximal partial correlations.) Without setting up any empirical radiation pressure parameter, we obtain maximal partial correlations of 99.98 % for all 3 components of the origin: a geocenter error can almost perfectly be absorbed by the other GNSS parameters. Satellite clock offsets, if estimated epoch-wise, especially devastate the sensitivity of GNSS to geocenter motion. The numerous station-related parameters (station positions, station clock offsets, ZWDs and horizontal tropospheric gradients) do the rest of the job. The maximal partial correlations increase a bit more when the classic "ECOM" set of 5 radiation pressure parameters is set up for each satellite. But this increase is almost fully attributable to the once-per-revolution parameters BC & BS. In particular, we do not find the direct radiation pressure parameters D0 to play a predominant role in the GNSS geocenter determination problem.

Influence of barley grain treated with alkaline compounds or organic extracts on ex vivo site and extent of digestion of starch.

PubMed

Naseroleslami, Reza; Mesgaran, Mohsen Danesh; Tahmasbi, Abdolmansour; Vakili, Seyed Alireza; Ebrahimi, Seyed Hadi

2018-02-01

Two e x vivo experiments were conducted to verify the effect of barley grain ( Nusrat cultivar ) treated with alkaline compounds (AC) including alum, ammonium, and sodium hydroxide or cation-exchanged organic extracts (OE) prepared from alfalfa hay, sugar beet pulp and Ulva Fasciata , on extent and digestion of starch. In the first study, the in vitro first order disappearance kinetic parameters of dry matter (DM), crude protein (CP) and starch were estimated using a non-linear model (D (t) = D (i) · e (-k d · time) + I, where: D (t) = potentially digestible residues at any time, D (i) = potentially digestible fraction at any time, k d = fractional rate constant of digestion (/h), I = indigestible fraction at any time). In the second experiment, the ruminal and post-ruminal disappearance of DM, CP, and starch were determined using in situ mobile nylon bag. Barley grains treated with alum and alfalfa extract had a higher constant rate of starch digestion (0.11 and 0.09/h) than others. Barley grain treated with OE had a higher constant rate of CP digestion and that of treated with AC had a higher constant rate of starch digestion (0.08 and 0.11/h) compared with those of the other treatments. The indigestible fraction of starch treated with alum and sugar beet pulp extract was higher than that of the control group (0.24 and 0.25 vs 0.21). Barley grain treated with AC and OE had significant CP disappearance in the rumen, post-rumen and total tract, and also starch disappearance for post-rumen and total tract compared with the untreated (p<0.001). This study demonstrated that AC and OE might have positive effects on the starch degradation of the barley grain. In addition, treating barley grain with alum and sugar beet pulp extract could change the site and extend digestion of protein and starch.

Influence of barley grain treated with alkaline compounds or organic extracts on ex vivo site and extent of digestion of starch

PubMed Central

Vakili, Seyed Alireza

2018-01-01

Objective Two ex vivo experiments were conducted to verify the effect of barley grain (Nusrat cultivar) treated with alkaline compounds (AC) including alum, ammonium, and sodium hydroxide or cation-exchanged organic extracts (OE) prepared from alfalfa hay, sugar beet pulp and Ulva Fasciata, on extent and digestion of starch. Methods In the first study, the in vitro first order disappearance kinetic parameters of dry matter (DM), crude protein (CP) and starch were estimated using a non-linear model (D(t) = D(i) · e(−kd · time) + I, where: D(t) = potentially digestible residues at any time, D(i) = potentially digestible fraction at any time, kd = fractional rate constant of digestion (/h), I = indigestible fraction at any time). In the second experiment, the ruminal and post-ruminal disappearance of DM, CP, and starch were determined using in situ mobile nylon bag. Results Barley grains treated with alum and alfalfa extract had a higher constant rate of starch digestion (0.11 and 0.09/h) than others. Barley grain treated with OE had a higher constant rate of CP digestion and that of treated with AC had a higher constant rate of starch digestion (0.08 and 0.11/h) compared with those of the other treatments. The indigestible fraction of starch treated with alum and sugar beet pulp extract was higher than that of the control group (0.24 and 0.25 vs 0.21). Barley grain treated with AC and OE had significant CP disappearance in the rumen, post-rumen and total tract, and also starch disappearance for post-rumen and total tract compared with the untreated (p<0.001). Conclusion This study demonstrated that AC and OE might have positive effects on the starch degradation of the barley grain. In addition, treating barley grain with alum and sugar beet pulp extract could change the site and extend digestion of protein and starch. PMID:28728361

Activated carbon with excellent chromium(VI) adsorption performance prepared by acid-base surface modification.

PubMed

Liu, S X; Chen, X; Chen, X Y; Liu, Z F; Wang, H L

2007-03-06

In the present work, activated carbon (AC) with excellent Cr(VI) adsorption performance especially at low concentrations was prepared by an acid-base surface modification method. Raw activated carbon (AC(0)) was first oxidized in boiling HNO(3) (AC(1)), then treated with a mixture of NaOH and NaCl (AC(2)). Batch equilibrium and continuous column adsorption were conducted to evaluate the adsorption performance. Boehm titration, elemental analysis, and N(2)/77K adsorption isotherm methods were used to characterize the surface properties and pore structure of modified ACs. The results revealed that the modified AC exhibited excellent Cr(VI) adsorption performance in terms of adsorption capacity and adsorption rate: AC(2)>AC(1)>AC(0). Modification caused S(BET) to decrease and the total number of surface oxygen acidic groups to increase. HNO(3) oxidization produced positive acid groups, and subsequently NaOH treatment replaced H(+) of surface acid groups by Na(+), and the acidity of AC decreased. The main cause of higher Cr(VI) adsorption capacity and rate for AC(2) was the presence of more oxygen surface acidic groups and suitable surface acidity. HNO(3)-NaOH modification shows potential for the preparation of high quality AC for the effective removal of low concentrations of Cr(VI).

Source positions from VLBI combined solution

NASA Astrophysics Data System (ADS)

Bachmann, S.; Thaller, D.; Engelhardt, G.

2014-12-01

The IVS Combination Center at BKG is primarily responsible for combined Earth Orientation Parameter (EOP) products and the generation of a terrestrial reference frame based on VLBI observations (VTRF). The procedure is based on the combination of normal equations provided by six IVS Analysis Centers (AC). Since more and more ACs also provide source positions in the normal equations - beside EOPs and station coordinates - an estimation of these parameters is possible and should be investigated. In the past, the International Celestial Reference Frame (ICRF) was not generated as a combined solution from several individual solutions, but was based on a single solution provided by one AC. The presentation will give an overview on the combination strategy and the possibilities for combined source position determination. This includes comparisons with existing catalogs, quality estimation and possibilities of rigorous combination of EOP, TRF and CRF in one combination process.

Broadband Laser Ranging for Position Measurements in Shock Physics Experiments

NASA Astrophysics Data System (ADS)

Rhodes, Michelle; Bennett, Corey; Daykin, Edward; Younk, Patrick; Lalone, Brandon; Kostinski, Natalie

2017-06-01

Broadband laser ranging (BLR) is a recently developed measurement system that provides an attractive option for determining the position of shock-driven surfaces. This system uses broadband, picosecond (or femtosecond) laser pulses and a fiber interferometer to measure relative travel time to a target and to a reference mirror. The difference in travel time produces a delay difference between pulse replicas that creates a spectral beat frequency. The spectral beating is recorded in real time using a dispersive Fourier transform and an oscilloscope. BLR systems have been designed that measure position at 12.5-40 MHz with better than 100 micron accuracy over ranges greater than 10 cm. We will give an overview of the basic operating principles of these systems. Prepared by LLNL under Contract DE-AC52-07NA27344, by LANL under Contract DE-AC52-06NA25396, and by NSTec Contract DE-AC52-06NA25946.

Some Observations on Damage Tolerance Analyses in Pressure Vessels

NASA Technical Reports Server (NTRS)

Raju, Ivatury S.; Dawicke, David S.; Hampton, Roy W.

2017-01-01

AIAA standards S080 and S081 are applicable for certification of metallic pressure vessels (PV) and composite overwrap pressure vessels (COPV), respectively. These standards require damage tolerance analyses with a minimum reliable detectible flaw/crack and demonstration of safe life four times the service life with these cracks at the worst-case location in the PVs and oriented perpendicular to the maximum principal tensile stress. The standards require consideration of semi-elliptical surface cracks in the range of aspect ratios (crack depth a to half of the surface length c, i.e., (a/c) of 0.2 to 1). NASA-STD-5009 provides the minimum reliably detectible standard crack sizes (90/95 probability of detection (POD) for several non-destructive evaluation (NDE) methods (eddy current (ET), penetrant (PT), radiography (RT) and ultrasonic (UT)) for the two limits of the aspect ratio range required by the AIAA standards. This paper tries to answer the questions: can the safe life analysis consider only the life for the crack sizes at the two required limits, or endpoints, of the (a/c) range for the NDE method used or does the analysis need to consider values within that range? What would be an appropriate method to interpolate 90/95 POD crack sizes at intermediate (a/c) values? Several procedures to develop combinations of a and c within the specified range are explored. A simple linear relationship between a and c is chosen to compare the effects of seven different approaches to determine combinations of aj and cj that are between the (a/c) endpoints. Two of the seven are selected for evaluation: Approach I, the simple linear relationship, and a more conservative option, Approach III. For each of these two Approaches, the lives are computed for initial semi-elliptic crack configurations in a plate subjected to remote tensile fatigue loading with an R-ratio of 0.1, for an assumed material evaluated using NASGRO (registered 4) version 8.1. These calculations demonstrate that for this loading, using Approach I and the initial detectable crack sizes at the (a/c) endpoints in 5009 specified for the ET and UT NDE methods, the smallest life is not at the two required limits of the (a/c) range, but rather is at an intermediate configuration in the range (a/c) of 0.4 to 0.6. Similar analyses using both Approach I and III with the initial detectable crack size at the (a/c) endpoints in 5009 for PT NDE showed the smallest life may be at an (a/c) endpoint or an intermediate (a/c), depending upon which Approach is used. As such, analyses that interrogate only the two (a/c) values of 0.2 and 1 may result in unconservative life predictions. The standard practice may need to be revised based on these results.

Preliminary design of a Primary Loop Pump Assembly (PLPA), using electromagnetic pumps

NASA Technical Reports Server (NTRS)

Moss, T. A.; Matlin, G.; Donelan, L.; Johnson, J. L.; Rowe, I.

1972-01-01

A preliminary design study of flight-type dc conduction-permanent magnetic, ac helical induction, and ac linear induction pumps for circulating 883 K (1130 F) NaK at 9.1 kg/sec (20 lb/sec) is described. Various electromagnetic pump geometrics are evaluated against hydraulic performance, and the effects of multiple windings and numbers of pumps per assembly on overall reliability were determined. The methods used in the electrical-hydraulic, stress, and thermal analysis are discussed, and the high temperature electrical materials selected for the application are listed.

Hounsfield Unit inaccuracy in computed tomography lesion size and density, diagnostic quality vs attenuation correction

NASA Astrophysics Data System (ADS)

Szczepura, Katy; Thompson, John; Manning, David

2017-03-01

In computed tomography the Hounsfield Units (HU) are used as an indicator of the tissue type based on the linear attenuation coefficients of the tissue. HU accuracy is essential when this metric is used in any form to support diagnosis. In hybrid imaging, such as SPECT/CT and PET/CT, the information is used for attenuation correction (AC) of the emission images. This work investigates the HU accuracy of nodules of known size and HU, comparing diagnostic quality (DQ) images with images used for AC.

Modified Activated Carbon Prepared from Acorn Shells as a New Solid-Phase Extraction Sorbent for the Preconcentration and Determination of Trace Amounts of Nickel in Food Samples Prior to Flame Atomic Absorption Spectrometry.

PubMed

Ebrahimi, Bahram

2017-03-01

A new solid-phase extraction (SPE) sorbent was introduced based on acidic-modified (AM) activated carbon (AC) prepared from acorn shells of native oak trees in Kurdistan. Hydrochloric acid (15%, w/w) and nitric acid (32.5%, w/w) were used to condition and modify AC. The IR spectra of AC and AM-AC showed that AM lead to the formation of increasing numbers of acidic functional groups on AM-AC. AM-AC was used in the SPE method for the extraction and preconcentration of Ni+2 prior to flame atomic absorption spectrometric determination at ng/mL levels in model and real food samples. Effective parameters of the SPE procedure, such as the pH of the solutions, sorbent dosage, extraction time, sample volume, type of eluent, and matrix ions, were considered and optimized. An enrichment factor of 140 was obtained. The calibration curve was linear with an R2 of 0.997 in the concentration range of 1-220 ng/mL. The RSD was 5.67% (for n = 7), the LOD was 0.352 ng/mL, and relative recoveries in vegetable samples ranged from 96.7 to 103.7%.

From Beamline to Scanner with 225Ac

NASA Astrophysics Data System (ADS)

Robertson, Andrew K. H.; Ramogida, Caterina F.; Kunz, Peter; Rodriguez-Rodriguez, Cristina; Schaffer, Paul; Sossi, Vesna

2016-09-01

Due to the high linear energy transfer and short range of alpha-radiation, targeted radiation therapy using alpha-emitting pharmaceuticals that successfully target small disease clusters will kill target cells with limited harm to healthy tissue, potentially treating the most aggressive forms of cancer. As the parent of a decay chain with four alpha- and two beta-decays, 225Ac is a promising candidate for such a treatment. However, this requires retention of the entire decay chain at the target site, preventing the creation of freely circulating alpha-emitters that reduce therapeutic effect and increase toxicity to non-target tissues. Two major challenges to 225Ac pharmaceutical development exist: insufficient global supply, and the difficulty of preventing toxicity by retaining the entire decay chain at the target site. While TRIUMF works towards large-scale (C i amounts) production of 225Ac, we already use our Isotope Separation On-Line facility to provide small (< 1 mCi) quantities for in-house chemistry and imaging research that aims to improve and assess 225Ac radiopharmaceutical targeting. This presentation provides an overview of this research program and the journey of 225Ac from the beamline to the scanner. This research is funded by the Natural Sciences and Engineering Research Council of Canada.

[Expression of AC133 vs. CD34 in acute childhood leukemias].

PubMed

Ebener, U; Brinkmann, A; Zotova, V; Niegemann, E; Wehner, S

2000-01-01

AC133, a newly discovered antigen on human progenitor cells, demonstrating 5-transmembranous domains is expressed by 30-60% out of all CD34+ cells. Our aim therefore was to investigate the extent of human stem-/progenitor cells expressing AC133 antigen in umbilical cord blood, peripheral blood without or following an application of granulocyte-colony stimulating factor (rhG-CSF). The main task was the investigation of bone marrow aspirates derived from children suffering from newly diagnosed acute leukemias, as well as from patients with a relapse or during a complete remission. The determination of antigen expression was done by application of flow cytometry (FACScan analysis) and the usage of newly developed monoclonal antibodies (AC133/1 and AC133/2; Miltenyi Biotec GmbH) in combination with monoclonal antibody directed against CD34-antigens (HPCA-2; BD). Our studies till now show average percentages in umbilical cord blood derived from 43 newborns about 0.294 +/- 0.165% AC133+ vs. 0.327 +/- 0.156% CD34+ hematopoietic stem-/progenitor cells (HSPC). In peripheral blood from 11 healthy donors we verified up to 0.15% CD34+ as well as AC133+ HSPC's. The concentration of progenitor cells was found to be obviously higher in peripheral blood from children with various diseases (neuroblastoma, rhabdomyosarcoma, ALL/AML) and undergoing application with rhG-CSF in order to be prepared for PBSC-transplantation. In those cases we found up to 3.51% AC133+ cells as well as slightly higher values (3.94%) for CD34 antigens. Additionally we quantified 128 bone marrow (BM) samples for AC133+ and CD34+ cells. In 10 BM samples, derived from patients without any neoplasia, the CD34+ cells were about 0.03% and 1.49%, whereas AC133 values were up to 0.64%. Bone marrow aspirates from 53 children with acute leukemias at time of diagnosis (ALL: n = 41/AML: n = 12) have been immunophenotyped and leukemic blast cells have been proved for AC133- and CD34 antigen expression. 32/41 (78%) of lymphoblastic leukemic cells showed to be positive for CD34 antigen and 24/41 (58%) demonstrated AC133 antigens. Interestingly there were 2 ALL-patients with pathological blast cells positive for AC133 but lacking of any CD34 antigens. 42% (5/12) of investigated AML patients showed CD34+ phenotype, on the other hand there were only 25% (3/12) with AC133+ phenotype. Similar values were found in relapsed patients (n = 18). In BM samples from patients during complete remission (n = 47) we could detect percentages up to 5.55% for CD34 and up to 1.25% for AC133 positive stem-/progenitor cells. Such quite high data may be explained by occasionally application of rhG-CSF therapy. Our results till now lead to the conclusion, that it seems to be useful, to recruit quantification of CD34+ HPSC by additionally detecting AC133 antigens. This new stem cell marker (AC133) may be of great value in case of autologous peripheral blood stem cell transplantation (PBSCT) because it could be an alternative to the usual CD34+ MACS selection system.

Acute coronary syndrome vs nonspecific troponin elevation: clinical predictors and survival analysis.

PubMed

Alcalai, Ronny; Planer, David; Culhaoglu, Afsin; Osman, Aydin; Pollak, Arthur; Lotan, Chaim

2007-02-12

Although troponin is considered a specific marker for the diagnosis of acute coronary syndrome (ACS), recent studies have shown troponin elevation in a variety of nonischemic conditions. Our aim was to determine the predictors for the diagnosis of ACS in the presence of an abnormal troponin level. All patients with abnormal troponin T levels were analyzed. Demographic and clinical data were collected and death was recorded. The study group was divided into 2 subgroups: ACS vs nonthrombotic troponin elevation. A multivariate logistic regression analysis was performed to define variables that predict the diagnosis of ACS. The positive predictive value (PPV) for ACS diagnosis was calculated, and a survival analysis was performed. During the study period, 615 patients had elevated troponin T levels. Only 326 patients (53%) received a main diagnosis of ACS, while 254 (41%) had nonthrombotic troponin elevation; for 35 patients (6%), the diagnosis was not conclusive. Positive predictors for the diagnosis of ACS were age between 40 and 70 years, history of hypertension or ischemic heart disease, normal renal function, and a troponin T level higher than 1.0 ng/mL. The overall PPV of troponin T for ACS diagnosis was only 56% (95% CI, 52%-60%). The PPV of troponin T level higher than 1.0 ng/mL in the presence of normal renal function was 90% but was as low as 27% for values of 0.1 to 1.0 ng/mL for elderly patients with renal failure. In-hospital and long-term survival rates were significantly better (P<.001) for patients with ACS. Nonspecific troponin elevation is a common finding among hospitalized patients and correlates with worse prognosis. The diagnosis of myocardial infarction should still mostly be based on the clinical presentation. The predictors and algorithm suggested in this study might increase the diagnostic accuracy of ACS and direct the appropriate treatment.

Inhibitory Effect of Flavonoids on the Efflux of N-Acetyl 5-Aminosalicylic Acid Intracellularly Formed in Caco-2 Cells

PubMed Central

Shin, Yoshimura; Kentaro, Kawano; Ryusuke, Matsumura; Narumi, Sugihara; Koji, Furuno

2009-01-01

N-acetyl 5-aminosalicylic acid (5-AcASA) that was intracellularly formed from 5-aminosalicylic acid (5-ASA) at 200 μM was discharged 5.3, 7.1, and 8.1-fold higher into the apical site than into the basolateral site during 1, 2, and 4-hour incubations, respectively, in Caco-2 cells grown in Transwells. The addition of flavonols (100 μM) such as fisetin and quercetin with 5-ASA remarkably decreased the apically directed efflux of 5-AcASA. When 5-ASA (200 μM) was added to Caco-2 cells grown in tissue culture dishes, the formation of 5-AcASA decreased, and, in addition, the formed 5-AcASA was found to be accumulated within the cells in the presence of such flavonols. Thus, the decrease in 5-AcASA efflux by such flavonols was attributed not only to the inhibition of N-acetyl-conjugation of 5-ASA but to the predominant cellular accumulation of 5-AcASA. Various flavonoids also had both of the effects with potencies that depend on their specific structures. The essential structure of flavonoids was an absence of a hydroxyl substitution at the C5 position on the A-ring of flavone structure for the inhibitory effect on the N-acetyl-conjugation of 5-ASA, and a presence of hydroxyl substitutions at the C3′ or C4′ position on the B-ring of flavone structure for the promoting effect on the cellular accumulation of 5-AcASA. Both the decrease in 5-AcASA apical efflux and the increase in 5-AcASA cellular accumulation were also caused by MK571 and indomethacin, inhibitors of MRPs, but not by quinidine, cyclosporin A, P-glycoprotein inhibitors, and mitoxantrone, a BCRP substrate. These results suggest that certain flavonoids suppress the apical efflux of 5-AcASA possibly by inhibiting MRPs pumps located on apical membranes in Caco-2 cells. PMID:19688110

Ethylene induces combinatorial effects of histone H3 acetylation in gene expression in Arabidopsis.

PubMed

Wang, Likai; Zhang, Fan; Rode, Siddharth; Chin, Kevin K; Ko, Eun Esther; Kim, Jonghwan; Iyer, Vishwanath R; Qiao, Hong

2017-07-17

Histone acetylation and deacetylation are essential for gene regulation and have been implicated in the regulation of plant hormone responses. Many studies have indicated the role of histone acetylation in ethylene signaling; however, few studies have investigated how ethylene signaling regulates the genomic landscape of chromatin states. Recently, we found that ethylene can specifically elevate histone H3K14 acetylation and the non-canonical histone H3K23 acetylation in etiolated seedlings and the gene activation is positively associated with the elevation of H3K14Ac and H3K23Ac in response to ethylene. To assess the role of H3K9, H3K14, and H3K23 histone modifications in the ethylene response, we examined how ethylene regulates histone acetylation and the transcriptome at global level and in ethylene regulated genes both in wild type (Col-0) and ein2-5 seedlings. Our results revealed that H3K9Ac, H3K14Ac, and H3K23Ac are preferentially enriched around the transcription start sites and are positively correlated with gene expression levels in Col-0 and ein2-5 seedlings both with and without ethylene treatment. In the absence of ethylene, no combinatorial effect of H3K9Ac, H3K14Ac, and H3K23Ac on gene expression was detected. In the presence of ethylene, however, combined enrichment of the three histone acetylation marks was associated with high gene expression levels, and this ethylene-induced change was EIN2 dependent. In addition, we found that ethylene-regulated genes are expressed at medium or high levels, and a group of ethylene regulated genes are marked by either one of H3K9Ac, H3K14Ac or H3K23Ac. In this group of genes, the levels of H3K9Ac were altered by ethylene, but in the absence of ethylene the levels of H3K9Ac and peak breadths are distinguished in up- and down- regulated genes. In the presence of ethylene, the changes in the peak breadths and levels of H3K14Ac and H3K23Ac are required for the alteration of gene expressions. Our study reveals that the plant hormone ethylene induces combinatorial effects of H3K9Ac, K14Ac and K23Ac histone acetylation in gene expression genome widely. Further, for a group of ethylene regulated genes, in the absence of ethylene the levels and the covered breadths of H3K9Ac are the preexist markers for distinguishing up- and down- regulated genes, the change in the peak breadths and levels of H3K14Ac and H3K23Ac are required for the alteration of gene expression in the presence of ethylene.

Disequilibrium After Traumatic Brain Injury: Vestibular Mechanisms

DTIC Science & Technology

2011-09-01

of otolith signal processing, including the integration of head acceleration26 and the disambiguation of linear ac- celeration signals related to tilt ...Foveal versus full-field visual stabilization strategies for translational and rotational head movements. J. Neurosci. 23: 1104–1108. 14. Walker, M.F., M...in the vestibular reflexes that compensate for linear movements of the head and body during standing and walking. The experimental protocol has two

Numerical simulation of the dielectrophoretic concentration of DNA particles and the effect of AC electroosmosis

NASA Astrophysics Data System (ADS)

Loucaides, N. G.; Georghiou, G. E.; Charalambous, C. D.

2007-04-01

The dielectrophoretic concentration of DNA particles suspended in a solution is investigated in a system of parallel electrodes, where the particles are attracted to the edges of the electrodes by positive dielectrophoresis. The AC electroosmotic motion of the fluid is also considered, as well as the diffusion of the particles, using the solution of the Smoluchowski equation. The results examine the effect of AC electroosmosis in steady state dielectrophoretic concentration of particles, by demonstrating that AC electroosmosis significantly reduces the dielectrophoretic concentration at the edges and moves the particles towards the electrode centres.

Quality and Safety in Health Care, Part XVII: The ACS National Surgical Quality Improvement Program.

PubMed

Harolds, Jay A

2016-12-01

Mainly due to the positive effect on quality and safety from the Veterans Health Administration National Surgical Quality Improvement Program (VASQIP), a National Surgical Quality Improvement Program (NSQIP) for private hospitals was begun, which is now under the auspices of the American College of Surgeons (ACS). More than 600 hospitals now participate in the ACS-NSQIP. The information gained by the institutions is typically utilized to initiate quality improvement activities. The ACS-NSQIP also shares information on how to get better results, has national meetings, and provides other support.

Examining the Link Between Public Transit Use and Active Commuting

PubMed Central

Bopp, Melissa; Gayah, Vikash V.; Campbell, Matthew E.

2015-01-01

Background: An established relationship exists between public transportation (PT) use and physical activity. However, there is limited literature that examines the link between PT use and active commuting (AC) behavior. This study examines this link to determine if PT users commute more by active modes. Methods: A volunteer, convenience sample of adults (n = 748) completed an online survey about AC/PT patterns, demographic, psychosocial, community and environmental factors. t-test compared differences between PT riders and non-PT riders. Binary logistic regression analyses examined the effect of multiple factors on AC and a full logistic regression model was conducted to examine AC. Results: Non-PT riders (n = 596) reported less AC than PT riders. There were several significant relationships with AC for demographic, interpersonal, worksite, community and environmental factors when considering PT use. The logistic multivariate analysis for included age, number of children and perceived distance to work as negative predictors and PT use, feelings of bad weather and lack of on-street bike lanes as a barrier to AC, perceived behavioral control and spouse AC were positive predictors. Conclusions: This study revealed the complex relationship between AC and PT use. Further research should investigate how AC and public transit use are related. PMID:25898405

Examining the link between public transit use and active commuting.

PubMed

Bopp, Melissa; Gayah, Vikash V; Campbell, Matthew E

2015-04-17

An established relationship exists between public transportation (PT) use and physical activity. However, there is limited literature that examines the link between PT use and active commuting (AC) behavior. This study examines this link to determine if PT users commute more by active modes. A volunteer, convenience sample of adults (n = 748) completed an online survey about AC/PT patterns, demographic, psychosocial, community and environmental factors. t-test compared differences between PT riders and non-PT riders. Binary logistic regression analyses examined the effect of multiple factors on AC and a full logistic regression model was conducted to examine AC. Non-PT riders (n = 596) reported less AC than PT riders. There were several significant relationships with AC for demographic, interpersonal, worksite, community and environmental factors when considering PT use. The logistic multivariate analysis for included age, number of children and perceived distance to work as negative predictors and PT use, feelings of bad weather and lack of on-street bike lanes as a barrier to AC, perceived behavioral control and spouse AC were positive predictors. This study revealed the complex relationship between AC and PT use. Further research should investigate how AC and public transit use are related.

Electroconvection in one-dimensional liquid crystal cells

NASA Astrophysics Data System (ADS)

Huh, Jong-Hoon

2018-04-01

We investigate the alternating current (ac) -driven electroconvection (EC) in one-dimensional cells (1DCs) under the in-plane switching mode. In 1DCs, defect-free EC can be realized. In the presence and absence of external multiplicative noise, the features of traveling waves (TWs), such as their Hopf frequency fH and velocity, are examined in comparison with those of conventional two-dimensional cells (2DCs) accompanying defects of EC rolls. In particular, we show that the defects significantly contribute to the features of the TWs. Additionally, owing to the defect-free EC in the 1DCs, the effects of the ac and noise fields on the TW are clarified. The ac field linearly increases fH, independent of the ac frequency f . The noise increases fH monotonically, but fH does not vary below a characteristic noise intensity VN*. In addition, soliton-like waves and unfamiliar oscillation of EC vortices in 1DCs are observed, in contrast to the localized EC (called worms) and the oscillation of EC rolls in 2DCs.

Chance-Constrained AC Optimal Power Flow: Reformulations and Efficient Algorithms

DOE PAGES

Roald, Line Alnaes; Andersson, Goran

2017-08-29

Higher levels of renewable electricity generation increase uncertainty in power system operation. To ensure secure system operation, new tools that account for this uncertainty are required. Here, in this paper, we adopt a chance-constrained AC optimal power flow formulation, which guarantees that generation, power flows and voltages remain within their bounds with a pre-defined probability. We then discuss different chance-constraint reformulations and solution approaches for the problem. Additionally, we first discuss an analytical reformulation based on partial linearization, which enables us to obtain a tractable representation of the optimization problem. We then provide an efficient algorithm based on an iterativemore » solution scheme which alternates between solving a deterministic AC OPF problem and assessing the impact of uncertainty. This more flexible computational framework enables not only scalable implementations, but also alternative chance-constraint reformulations. In particular, we suggest two sample based reformulations that do not require any approximation or relaxation of the AC power flow equations.« less

Student Measurements of STFA 14 AC at Vanguard Preparatory School

NASA Astrophysics Data System (ADS)

Gillette, Sean; Archuleta, Alex; Diaz, Lizbeth; Gillespie, Kyle; Gosney, Timothy; Johnson, Stephen; Mohan, Nikita; Rajacich, Jacob; Roehl, Nathaniel; Sharpe, Scotty; Whitt, Kahaloha

2016-01-01

Eighth grade students at Vanguard Preparatory School measured the double star STFA 14 AC using a Bader Planetarium Micro Guide eyepiece. Navi (Gamma Cassiopeiae) was used as the ca libration star. The calculated means of multiple observations of STFA 14 AC resulted in a separation of 53.3" and a position angle of 2.0°. These measurements were compared to the most recent values in the Washington Double Star Catalog.

Is it feasible to diagnose catheter-related candidemia without catheter withdrawal?

PubMed

Fernández-Cruz, Ana; Martín-Rabadán, Pablo; Suárez-Salas, Marisol; Rojas-Wettig, Loreto; Pérez, María Jesús; Guinea, Jesús; Guembe, María; Peláez, Teresa; Sánchez-Carrillo, Carlos; Bouza, Emilio

2014-07-01

Many bloodstream infections (BSI) in patients with central venous catheters (CVC) are not catheter-related (CR). Assessment of catheter involvement without catheter withdrawal has not been studied in candidemia. We assessed the value of conservative techniques to evaluate catheters as the origin of candidemia in patients with CVC in a prospective cohort study (superficial Gram stain and culture, Kite technique (Gram stain and culture of the first 1 cm blood drawn from the CVC), proportion of positive blood cultures (PPBCs), differential time to positivity (DTP), and minimal time to positivity (MTP)). All catheters were cultured at withdrawal. From June 2008 to January 2012, 22 cases fulfilled the inclusion criteria. CR-candidemia (CRC) was confirmed in 10. Validity values for predicting CRC were: superficial Gram stain (S, 30%; Sp, 81.83%; PPV, 60%; NPV, 56.3%; Ac, 57.1%), superficial cultures (S, 40%; Sp, 75%; PPV, 57.1%; NPV, 60%; Ac, 59.1%), Kite Gram stain (S, 33.3%; Sp, 66.7%; PPV, 50%; NPV, 50%; Ac, 50%), Kite culture (S, 80%; Sp, 66.7%; PPV, 66.7%; NPV, 80%; Ac, 72.7%), PPBC (S, 50%; Sp, 41.7%; PPV, 41.7%; NPV, 50.0%; Ac, 45.5%), DTP (S, 100%; Sp, 33.3%; PPV, 55.6%; NPV, 100%; Ac, 63.6%), and MTTP (S, 70%; Sp, 58.3%; PPV, 58.3%; NPV, 70%; Ac, 63.6%). While combinations of two tests improved sensitivity and NPV, more than two tests did not improve validity values. Classic tests to assess CR-BSI caused by bacteria cannot be reliably used to diagnose CRC. Combinations of tests could be useful, but more and larger studies are required. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Contrasting Relationships between Betaine and Homocysteine in Two Clinical Cohorts are Associated with Plasma Lipids and Drug Treatments

PubMed Central

Lever, Michael; George, Peter M.; Atkinson, Wendy; Elmslie, Jane L.; Slow, Sandy; Molyneux, Sarah L.; Troughton, Richard W.; Richards, A. Mark; Frampton, Christopher M.; Chambers, Stephen T.

2012-01-01

Background Urinary betaine excretion positively correlated with plasma homocysteine in outpatients attending a lipid disorders clinic (lipid clinic study). We aimed to confirm this in subjects with established vascular disease. Methods The correlation between betaine excretion and homocysteine was compared in samples collected from subjects 4 months after hospitalization for an acute coronary episode (ACS study, 415 urine samples) and from 158 sequential patients visiting a lipid disorders clinic. Principal findings In contrast to the lipid clinic study, betaine excretion and plasma homocysteine did not correlate in the total ACS cohort. Differences between the patient groups included age, non-HDL cholesterol and medication. In ACS subjects with below median betaine excretion, excretion correlated (using log transformed data) negatively with plasma homocysteine (r = −0.17, p = 0.019, n = 199), with no correlation in the corresponding subset of the lipid clinic subjects. In ACS subjects with above median betaine excretion a positive trend (r = +0.10) between betaine excretion and homocysteine was not significant; the corresponding correlation in lipid clinic subjects was r = +0.42 (p = 0.0001). In ACS subjects, correlations were stronger when plasma non-HDL cholesterol and betaine excretion were above the median, r = +0.20 (p = 0.045); in subjects above median non-HDL cholesterol and below median betaine excretion, r = −0.26 (p = 0.012). ACS subjects taking diuretics or proton pump inhibitors had stronger correlations, negative with lower betaine excretion and positive with higher betaine excretion. Conclusions Betaine excretion correlates with homocysteine in subjects with elevated blood lipids. PMID:22396767

Colorimetric anion sensors based on positional effect of nitro group for recognition of biologically relevant anions in organic and aqueous medium, insight real-life application and DFT studies.

PubMed

Singh, Archana; Sahoo, Suban K; Trivedi, Darshak R

2018-01-05

A new six colorimetric receptors A1-A6 were designed and synthesized, characterized by typical common spectroscopic techniques like FT-IR, UV-Visible, 1 H NMR, 13 C NMR and ESI-MS. The receptor A1 and A2 exhibit a significant naked-eye response towards F - and AcO - ions in DMSO. Due to presences of the NO 2 group at para and ortho position with extended π-conjugation of naphthyl group carrying OH as a binding site. Compared to receptor A2, A1 is extremely capable of detecting F - and AcO - ions present in the form of sodium salts in an aqueous medium. This is owed to the occurrence of NO 2 group at para position induced in increasing the acidity of OH proton. Consequently, it easily gets deprotonated in aqueous media. The detection limit of receptor A1 was turned out to be 0.40 and 0.35ppm for F - and AcO - ions which is beneath WHO permission level (1.0ppm). Receptor A1 shows a solitary property of solvatochromism in different aprotic solvents in presence of AcO - ion. Receptor A1 depicts high selectivity towards AcO - ion in DMSO: HEPES buffer (9:1, v/v). Receptor A1 proved itself for real life application by detecting anion in solution and solid state. The binding mechanism of receptor A1 with AcO - and F - ions was monitored from 1 HNMR titration and DFT study. Copyright © 2017 Elsevier B.V. All rights reserved.

Equivalent circuit modeling of a piezo-patch energy harvester on a thin plate with AC-DC conversion

NASA Astrophysics Data System (ADS)

Bayik, B.; Aghakhani, A.; Basdogan, I.; Erturk, A.

2016-05-01

As an alternative to beam-like structures, piezoelectric patch-based energy harvesters attached to thin plates can be readily integrated to plate-like structures in automotive, marine, and aerospace applications, in order to directly exploit structural vibration modes of the host system without mass loading and volumetric occupancy of cantilever attachments. In this paper, a multi-mode equivalent circuit model of a piezo-patch energy harvester integrated to a thin plate is developed and coupled with a standard AC-DC conversion circuit. Equivalent circuit parameters are obtained in two different ways: (1) from the modal analysis solution of a distributed-parameter analytical model and (2) from the finite-element numerical model of the harvester by accounting for two-way coupling. After the analytical modeling effort, multi-mode equivalent circuit representation of the harvester is obtained via electronic circuit simulation software SPICE. Using the SPICE software, electromechanical response of the piezoelectric energy harvester connected to linear and nonlinear circuit elements are computed. Simulation results are validated for the standard AC-AC and AC-DC configurations. For the AC input-AC output problem, voltage frequency response functions are calculated for various resistive loads, and they show excellent agreement with modal analysis-based analytical closed-form solution and with the finite-element model. For the standard ideal AC input-DC output case, a full-wave rectifier and a smoothing capacitor are added to the harvester circuit for conversion of the AC voltage to a stable DC voltage, which is also validated against an existing solution by treating the single-mode plate dynamics as a single-degree-of-freedom system.

Tumor vascularity and hematogenous metastasis in experimental murine intraocular melanoma.

PubMed Central

Grossniklaus, H E

1998-01-01

PURPOSE: The purpose of this study is to test the hypothesis that primary tumor vascularity in a murine model of intraocular melanoma positively correlates with the development and hematogenous spread of metastasis. METHODS: Forty 12-week-old C57BL6 mice were inoculated in either the anterior chamber (AC) or posterior compartment (PC) of 1 eye with 5 x 10(5) cells/microL of Queens tissue culture melanoma cells. The inoculated eye was enucleated at 2 weeks; the mice were sacrificed at 4 weeks postinoculation, and necropsies were performed. The enucleated eyes were examined for histologic and ultrastructural features, including relationship of tumor cells to tumor vascular channels, vascular pattern, and mean vascular density. RESULTS: Melanoma grew and was confined to the eye in 12 of 20 AC eyes and 10 of 20 PC eyes. Histologic and electron microscopic examination showed tumor invasion into vascular channels. Five of 12 AC tumors (42%) and 8 of 10 PC tumors (80%) metastasized. All of the AC tumors, but none of the PC tumors, that distantly metastasized also metastasized to ipsilateral cervical lymph nodes (P = .00535). There was no statistically significant difference of vascular pattern between the melanomas that did and did not metastasize to lungs in the PC group (P = .24), although there was a significant difference in the AC group (P = .02). Tumors with high-grade vascular patterns were more likely to metastasize than tumors with low-grade vascular patterns in the AC group. The mean vascular density positively correlated with the presence and number of metastases in both groups (P = .0000 and P < .001, respectively). There was no statistically significant difference of vascular pattern and mean vascular density for AC versus PC melanoma (P = .97). CONCLUSIONS: The rate of metastasis in this murine intraocular melanoma model positively correlates with primary tumor vascularity. The melanoma metastasizes via invasion of tumor vascular channels. AC melanoma also metastasizes through regional lymphatics. Images FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 FIGURE 14 FIGURE 15 FIGURE 16 PMID:10360307

Logarithms in the Year 10 A.C.

ERIC Educational Resources Information Center

Kalman, Dan; Mitchell, Charles E.

1981-01-01

An alternative application of logarithms in the high school algebra curriculum that is not undermined by the existence and widespread availability of calculators is presented. The importance and use of linear relationships are underscored in the proposed lessons. (MP)

Structure of the cellulose synthase complex of Gluconacetobacter hansenii at 23.4 Å resolution

DOE PAGES

Du, Juan; Vepachedu, Venkata; Cho, Sung Hyun; ...

2016-05-23

Bacterial crystalline cellulose is used in biomedical and industrial applications, but the molecular mechanisms of synthesis are unclear. Unlike most bacteria, which make non-crystalline cellulose, Gluconacetobacter hansenii extrudes profuse amounts of crystalline cellulose. Its cellulose synthase (AcsA) exists as a complex with accessory protein AcsB, forming a 'terminal complex' (TC) that has been visualized by freeze-fracture TEM at the base of ribbons of crystalline cellulose. The catalytic AcsAB complex is embedded in the cytoplasmic membrane. The C-terminal portion of AcsC is predicted to form a translocation channel in the outer membrane, with the rest of AcsC possibly interacting with AcsDmore » in the periplasm. It is thus believed that synthesis from an organized array of TCs coordinated with extrusion by AcsC and AcsD enable this bacterium to make crystalline cellulose. The only structural data that exist for this system are the above mentioned freeze-fracture TEM images, fluorescence microscopy images revealing that TCs align in a row, a crystal structure of AcsD bound to cellopentaose, and a crystal structure of PilZ domain of AcsA. Here we advance our understanding of the structural basis for crystalline cellulose production by bacterial cellulose synthase by determining a negative stain structure resolved to 23.4 angstrom for highly purified AcsAB complex that catalyzed incorporation of UDP-glucose into β-1,4-glucan chains, and responded to the presence of allosteric activator cyclic diguanylate. Although the AcsAB complex was functional in vitro, the synthesized cellulose was not visible in TEM. The negative stain structure revealed that AcsAB is very similar to that of the BcsAB synthase of Rhodobacter sphaeroides, a non-crystalline cellulose producing bacterium. Furthermore, the results indicate that the crystalline cellulose producing and non-crystalline cellulose producing bacteria share conserved catalytic and membrane translocation components, and support the hypothesis that it is the extrusion mechanism and order in linearly arrayed TCs that enables production of crystalline cellulose.« less

Structure of the cellulose synthase complex of Gluconacetobacter hansenii at 23.4 Å resolution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Du, Juan; Vepachedu, Venkata; Cho, Sung Hyun

Bacterial crystalline cellulose is used in biomedical and industrial applications, but the molecular mechanisms of synthesis are unclear. Unlike most bacteria, which make non-crystalline cellulose, Gluconacetobacter hansenii extrudes profuse amounts of crystalline cellulose. Its cellulose synthase (AcsA) exists as a complex with accessory protein AcsB, forming a 'terminal complex' (TC) that has been visualized by freeze-fracture TEM at the base of ribbons of crystalline cellulose. The catalytic AcsAB complex is embedded in the cytoplasmic membrane. The C-terminal portion of AcsC is predicted to form a translocation channel in the outer membrane, with the rest of AcsC possibly interacting with AcsDmore » in the periplasm. It is thus believed that synthesis from an organized array of TCs coordinated with extrusion by AcsC and AcsD enable this bacterium to make crystalline cellulose. The only structural data that exist for this system are the above mentioned freeze-fracture TEM images, fluorescence microscopy images revealing that TCs align in a row, a crystal structure of AcsD bound to cellopentaose, and a crystal structure of PilZ domain of AcsA. Here we advance our understanding of the structural basis for crystalline cellulose production by bacterial cellulose synthase by determining a negative stain structure resolved to 23.4 angstrom for highly purified AcsAB complex that catalyzed incorporation of UDP-glucose into β-1,4-glucan chains, and responded to the presence of allosteric activator cyclic diguanylate. Although the AcsAB complex was functional in vitro, the synthesized cellulose was not visible in TEM. The negative stain structure revealed that AcsAB is very similar to that of the BcsAB synthase of Rhodobacter sphaeroides, a non-crystalline cellulose producing bacterium. Furthermore, the results indicate that the crystalline cellulose producing and non-crystalline cellulose producing bacteria share conserved catalytic and membrane translocation components, and support the hypothesis that it is the extrusion mechanism and order in linearly arrayed TCs that enables production of crystalline cellulose.« less

Structure of the Cellulose Synthase Complex of Gluconacetobacter hansenii at 23.4 Å Resolution

PubMed Central

Du, Juan; Vepachedu, Venkata; Cho, Sung Hyun; Kumar, Manish; Nixon, B. Tracy

2016-01-01

Bacterial crystalline cellulose is used in biomedical and industrial applications, but the molecular mechanisms of synthesis are unclear. Unlike most bacteria, which make non-crystalline cellulose, Gluconacetobacter hansenii extrudes profuse amounts of crystalline cellulose. Its cellulose synthase (AcsA) exists as a complex with accessory protein AcsB, forming a 'terminal complex' (TC) that has been visualized by freeze-fracture TEM at the base of ribbons of crystalline cellulose. The catalytic AcsAB complex is embedded in the cytoplasmic membrane. The C-terminal portion of AcsC is predicted to form a translocation channel in the outer membrane, with the rest of AcsC possibly interacting with AcsD in the periplasm. It is thus believed that synthesis from an organized array of TCs coordinated with extrusion by AcsC and AcsD enable this bacterium to make crystalline cellulose. The only structural data that exist for this system are the above mentioned freeze-fracture TEM images, fluorescence microscopy images revealing that TCs align in a row, a crystal structure of AcsD bound to cellopentaose, and a crystal structure of PilZ domain of AcsA. Here we advance our understanding of the structural basis for crystalline cellulose production by bacterial cellulose synthase by determining a negative stain structure resolved to 23.4 Å for highly purified AcsAB complex that catalyzed incorporation of UDP-glucose into β-1,4-glucan chains, and responded to the presence of allosteric activator cyclic diguanylate. Although the AcsAB complex was functional in vitro, the synthesized cellulose was not visible in TEM. The negative stain structure revealed that AcsAB is very similar to that of the BcsAB synthase of Rhodobacter sphaeroides, a non-crystalline cellulose producing bacterium. The results indicate that the crystalline cellulose producing and non-crystalline cellulose producing bacteria share conserved catalytic and membrane translocation components, and support the hypothesis that it is the extrusion mechanism and order in linearly arrayed TCs that enables production of crystalline cellulose. PMID:27214134

Contemporary Population-Based Comparison of Localized Ductal Adenocarcinoma and High-Risk Acinar Adenocarcinoma of the Prostate.

PubMed

Packiam, Vignesh T; Patel, Sanjay G; Pariser, Joseph J; Richards, Kyle A; Weiner, Adam B; Paner, Gladell P; VanderWeele, David J; Zagaja, Gregory P; Eggener, Scott E

2015-10-01

To compare pathological characteristics, treatment patterns, and survival in patients with ductal adenocarcinoma (DC) compared to those with acinar adenocarcinoma (AC). Using the National Cancer Database, we identified patients diagnosed with clinically localized (cN0, cM0) pure DC (n = 1328) and AC (n = 751,635) between 1998 and 2011. High-risk AC was defined as Gleason 8-10. Demographic, treatment, pathological, and survival characteristics of patients were compared. Compared to patients with Gleason 8-10 AC, those with DC presented with lower mean prostate-specific antigen (10.3 vs 16.2 ng/mL, P <.001), had similar rates (11.7% vs 11.5%, P = .8) of clinical extra-capsular extension (stage ≥ cT3), and were more likely to undergo prostatectomy (54% vs 36%, P <.001). Compared to patients with Gleason 8-10 AC undergoing prostatectomy, those with DC had more favorable pathology: stage ≥ T3 (39% vs 52%, P <.001), fewer positive lymph nodes (4% vs 11%, P <.001), and fewer positive margins (25% vs 33%, P <.001). On Kaplan-Meier analysis, patients with DC had similar 5-year survival (75.0%, 95% confidence interval [CI] [71.7-78.9]) compared to those with Gleason 8-10 AC (77.1%, 95% CI [76.6%-77.6%], P = .2). On Cox multivariable analysis, patients with Gleason 8-10 AC had a similar risk of death compared to those with DC (hazards ratio = 0.92, 95% CI [0.69-1.23], P = 6). In this large contemporary population-based series, patients with DC of the prostate presented with lower prostate-specific antigen, had more favorable pathological features, and similar overall survival compared to men with Gleason 8-10 AC. Copyright © 2015 Elsevier Inc. All rights reserved.

Coping and metabolic syndrome indicators in urban black South African men: the SABPA study.

PubMed

du Plessis, A; Malan, L; Malan, N T

2010-01-01

Urbanisation is associated with obesity, hypertension and development of the metabolic syndrome (MS). We aimed to assess the use of different coping styles and their influence on increases in MS indicators and target end-organ damage (TOD) in urban black African men. A sample of 53 men was classified as clear high active (AC, n = 30) or passive coping (PC, n = 23) responders, using the Amirkhan African validated coping style indicator. Blood pressure (BP) was recorded with an aneroid sphygmomanometer and waist circumference (WC) was determined. Carotid intima-media thickness (CIMT) and microalbuminuria were analysed to determine TOD. Fasting serum and eight-hour urine samples revealed elevated MS indicators in AC men. Strong associations existed between MS indicators and TOD in AC but not PC men. To conclude, only BP and seeking social support were positively associated with TOD in urban PC African men, while in urban AC African men, most MS indicators were positively associated with TOD, i.e. sub-clinical atherosclerosis and renal impairment.

Reactions of the linear tetranuclear complex Ru sub 4 (CO) sub 10 (CH sub 3 C double bond C(H)C(H) double bond N-i-Pr) sub 2 with oxidizing reagents. Syntheses of halide-bridged (Ru(CO) sub 2 X(CH sub 3 C double bond C(H)C(H) double bond N-i-Pr)) sub 2 and fac-Ru(CO) sub 3 X(CH sub 3 C double bond C(H)C(H) double bond N-i-Pr)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mul, W.P.; Elsevier, C.J.; van Leijen, M.

1991-01-01

The linear tetranuclear complex Ru{sub 4}(CO){sub 10}(CH{sub 3}C{double bond}C(H)C(H){double bond}N-i-Pr){sub 2} (1), containing two {eta}{sup 5}-azaruthenacyclopentadienyl systems, reacts with oxidizing reagents (I{sub 2}, Br{sub 2}, NBS, CCl{sub 4}) at elevated temperatures (40-90C) in heptane or benzene to give the new dimeric halide-bridged organoruthenium(II) complexes (Ru(CO){sub 2}X(CH{sub 3}C{double bond}C(H)C(H){double bond}N-i-Pr)){sub 2} (X = I (3a), X = Br (3b), Cl (3c); yield 30-80%) together with (Ru(CO){sub 3}X{sub 2}){sub 2}. The reactions of 1 with CX{sub 4} (X = I, Br, Cl) are accelerated by CO, probably because Ru{sub 4}(CO){sub 12}(CH{sub 3}C{double bond}C(H)C(H){double bond}N-i-Pr){sub 2} (5), which contains two unbridged metal-metal bonds,more » is formed prior to oxidation. The halide-bridged dimers 3a-c are obtained as mixtures of four isomers, the configurations of which are discussed. Splitting of the halide bridges takes place when a solution of 3a-c is saturated with CO, whereby mononuclear fac-Ru(CO){sub 3}X(CH{sub 3}C{double bond}C(H)C(H){double bond}N-i-Pr) (4a-c) is obtained. This process is reversible; ie., passing a stream of nitrogen through a solution of 4a-c or removal of the solvent under vacuum causes the reverse reaction with reformation of 3a-c. Compounds 3a-c and 4a-c have been characterized by IR (3, 4), FD mass (3), {sup 1}H (3, 4), and {sup 13}C{l brace}H{r brace} NMR (4) spectroscopy and satisfactory elemental analyses have been obtained for 3a-c. Compounds 3 and 4 are suitable precursors for the preparation of new homo- and heteronuclear transition-metal complexes.« less

Good Trellises for IC Implementation of Viterbi Decoders for Linear Block Codes

NASA Technical Reports Server (NTRS)

Moorthy, Hari T.; Lin, Shu; Uehara, Gregory T.

1997-01-01

This paper investigates trellis structures of linear block codes for the integrated circuit (IC) implementation of Viterbi decoders capable of achieving high decoding speed while satisfying a constraint on the structural complexity of the trellis in terms of the maximum number of states at any particular depth. Only uniform sectionalizations of the code trellis diagram are considered. An upper-bound on the number of parallel and structurally identical (or isomorphic) subtrellises in a proper trellis for a code without exceeding the maximum state complexity of the minimal trellis of the code is first derived. Parallel structures of trellises with various section lengths for binary BCH and Reed-Muller (RM) codes of lengths 32 and 64 are analyzed. Next, the complexity of IC implementation of a Viterbi decoder based on an L-section trellis diagram for a code is investigated. A structural property of a Viterbi decoder called add-compare-select (ACS)-connectivity which is related to state connectivity is introduced. This parameter affects the complexity of wire-routing (interconnections within the IC). The effect of five parameters namely: (1) effective computational complexity; (2) complexity of the ACS-circuit; (3) traceback complexity; (4) ACS-connectivity; and (5) branch complexity of a trellis diagram on the very large scale integration (VISI) complexity of a Viterbi decoder is investigated. It is shown that an IC implementation of a Viterbi decoder based on a nonminimal trellis requires less area and is capable of operation at higher speed than one based on the minimal trellis when the commonly used ACS-array architecture is considered.

Good trellises for IC implementation of viterbi decoders for linear block codes

NASA Technical Reports Server (NTRS)

Lin, Shu; Moorthy, Hari T.; Uehara, Gregory T.

1996-01-01

This paper investigates trellis structures of linear block codes for the IC (integrated circuit) implementation of Viterbi decoders capable of achieving high decoding speed while satisfying a constraint on the structural complexity of the trellis in terms of the maximum number of states at any particular depth. Only uniform sectionalizations of the code trellis diagram are considered. An upper bound on the number of parallel and structurally identical (or isomorphic) subtrellises in a proper trellis for a code without exceeding the maximum state complexity of the minimal trellis of the code is first derived. Parallel structures of trellises with various section lengths for binary BCH and Reed-Muller (RM) codes of lengths 32 and 64 are analyzed. Next, the complexity of IC implementation of a Viterbi decoder based on an L-section trellis diagram for a code is investigated. A structural property of a Viterbi decoder called ACS-connectivity which is related to state connectivity is introduced. This parameter affects the complexity of wire-routing (interconnections within the IC). The effect of five parameters namely: (1) effective computational complexity; (2) complexity of the ACS-circuit; (3) traceback complexity; (4) ACS-connectivity; and (5) branch complexity of a trellis diagram on the VLSI complexity of a Viterbi decoder is investigated. It is shown that an IC implementation of a Viterbi decoder based on a non-minimal trellis requires less area and is capable of operation at higher speed than one based on the minimal trellis when the commonly used ACS-array architecture is considered.

Structure of gel phase saturated lecithin bilayers: temperature and chain length dependence.

PubMed Central

Sun, W J; Tristram-Nagle, S; Suter, R M; Nagle, J F

1996-01-01

Systematic low-angle and wide-angle x-ray scattering studies have been performed on fully hydrated unoriented multilamamellar vesicles of saturated lecithins with even chain lengths N = 16, 18, 20, 22, and 24 as a function of temperature T in the normal gel (L beta') phase. For all N, the area per chain Ac increases linearly with T with an average slope dAc/dT = 0.027 A2/degree C, and the lamellar D-spacings also increase linearly with an average slope dD/dT = 0.040 A/degree C. At the same T, longer chain length lecithins have more densely packed chains, i.e., smaller Ac's, than shorter chain lengths. The chain packing of longer chain lengths is found to be more distorted from hexagonal packing than that of smaller N, and the distortion epsilon of all N approaches the same value at the respective transition temperatures. The thermal volume expansion of these lipids is accounted for by the expansion in the hydrocarbon chain region. Electron density profiles are constructed using four orders of low-angle lamellar peaks. These show that most of the increase in D with increasing T is due to thickening of the bilayers that is consistent with a decrease in tilt angle theta and with little change in water spacing with either T or N. Because of the opposing effects of temperature on area per chain Ac and tilt angle 0, the area expansivity alpha A is quite small. A qualitative theoretical model based on competing head and chain interactions accounts for our results. PMID:8842227

A theoretical model for the production of Ac-225 for cancer therapy by photon-induced transmutation of Ra-226.

PubMed

Melville, G; Fan Liu, Sau; Allen, B J

2006-09-01

Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. We are investigating the reduction of radium by transmutation on a small scale by bombarding Ra-226 with high-energy photons from a medical linear accelerator (linac) to produce Ra-225, which subsequently decays to Ac-225, which can be used as a generator to produce Bi-213 for use in 'targeted alpha therapy' for cancer. This paper examines the possibility of producing Ac-225 with a linac using an accurate theoretical model in which the bremsstrahlung photon spectrum at 18 MV linac electron energy is convoluted with the corresponding photonuclear cross sections of Ra-226. The total integrated yield can then be obtained and is compared with a computer simulation. This study shows that at 18 MV, the photonuclear reaction on Ra-226 can produce low activities of Ac-225 with a linac. However, a high power linac with high current, pulse length and frequency is needed to produce practical amounts of Ac-225 and a useful reduction of Ra-226.

Signatures of filamentary superconductivity in antiferromagnetic BaFe 2As 2 single crystals

DOE PAGES

Moseley, D. A.; Yates, K. A.; Branford, W. R.; ...

2015-08-24

In this paper, we present ac susceptibility and magnetotransport measurements on aged single crystals of the ferropnictide parent compound, BaFe 2As 2 with a paramagnetic-to-antiferromagnetic transition temperature of 134 K. The ac susceptibility shows the clear onset of a partial diamagnetic response with an onset temperature, commensurate with a subtle downturn in resistivity at approximately 20 K. Below 20 K the magnetotransport shows in-plane anisotropy, magnetic-field history dependence and a hysteretic signature. Above 20 K the crystals show the widely reported high-field linear magnetoresistance. An enhanced noise signature in ac susceptibility is observed above 20 K, which varies in character with amplitude and frequency of the ac signal. The hysteresis in magnetoresistance and the observed sensitivity of the superconducting phase to the amplitude of the ac signal are indicative characteristics of granular or weakly linked filamentary superconductivity. Furthermore, these features taken together with the observed noise signature abovemore » $$T_{\\mathrm{c}}$$ suggests a link between the formation of the superconducting filamentary phase and the freezing of antiphase domain walls, known to exist in these materials.« less

Multilayered Regulation of Ethylene Induction Plays a Positive Role in Arabidopsis Resistance against Pseudomonas syringae1[OPEN

PubMed Central

Guan, Rongxia; Su, Jianbin; Meng, Xiangzong; Li, Sen; Liu, Yidong; Xu, Juan; Zhang, Shuqun

2015-01-01

Ethylene, a key phytohormone involved in plant-pathogen interaction, plays a positive role in plant resistance against fungal pathogens. However, its function in plant bacterial resistance remains unclear. Here, we report a detailed analysis of ethylene induction in Arabidopsis (Arabidopsis thaliana) in response to Pseudomonas syringae pv tomato DC3000 (Pst). Ethylene biosynthesis is highly induced in both pathogen/microbe-associated molecular pattern (PAMP)-triggered immunity and effector-triggered immunity (ETI), and the induction is potentiated by salicylic acid (SA) pretreatment. In addition, Pst actively suppresses PAMP-triggered ethylene induction in a type III secretion system-dependent manner. SA potentiation of ethylene induction is dependent mostly on MITOGEN-ACTIVATED PROTEIN KINASE6 (MPK6) and MPK3 and their downstream ACS2 and ACS6, two type I isoforms of 1-aminocyclopropane-1-carboxylic acid synthases (ACSs). ACS7, a type III ACS whose expression is enhanced by SA pretreatment, is also involved. Pst expressing the avrRpt2 effector gene (Pst-avrRpt2), which is capable of triggering ETI, induces a higher level of ethylene production, and the elevated portion is dependent on SALICYLIC ACID INDUCTION DEFICIENT2 and NONEXPRESSER OF PATHOGENESIS-RELATED GENE1, two key players in SA biosynthesis and signaling. High-order ACS mutants with reduced ethylene induction are more susceptible to both Pst and Pst-avrRpt2, demonstrating a positive role of ethylene in plant bacterial resistance mediated by both PAMP-triggered immunity and ETI. PMID:26265775

Comparative study of 0° X-cut and Y + 36°-cut lithium niobate high-voltage sensing

NASA Astrophysics Data System (ADS)

Patel, N.; Branch, D. W.; Schamiloglu, E.; Cular, S.

2015-08-01

A comparison study between Y + 36° and 0° X-cut lithium niobate (LiNbO3) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y + 36° crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5 μs voltage pulses to both crystals, the voltage-induced shift scaled linearly with voltage. For the Y + 36° cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz-100 kHz. Using the same conditions as the Y + 36° cut, the 0° X-cut crystal sensed a shift of 10-273 ps for DC voltages and 189-813 ps for AC voltage application. For 5 μs voltage pulses, the 0° X-cut crystal sensed a voltage induced shift of 0.250-2 ns and the Y + 36°-cut crystal sensed a time shift of 0.115-1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. When the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.

Comparative study of 0° X-cut and Y + 36°-cut lithium niobate high-voltage sensing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patel, N.; Department of Electrical and Computer Engineering, MSC01 1100, University of New Mexico, Albuquerque, New Mexico 87131-0001; Branch, D. W.

2015-08-15

A comparison study between Y + 36° and 0° X-cut lithium niobate (LiNbO{sub 3}) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y + 36° crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5more » μs voltage pulses to both crystals, the voltage-induced shift scaled linearly with voltage. For the Y + 36° cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz–100 kHz. Using the same conditions as the Y + 36° cut, the 0° X-cut crystal sensed a shift of 10–273 ps for DC voltages and 189–813 ps for AC voltage application. For 5 μs voltage pulses, the 0° X-cut crystal sensed a voltage induced shift of 0.250–2 ns and the Y + 36°-cut crystal sensed a time shift of 0.115–1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. When the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.« less

Comparative study of 0° X-cut and Y+36°-cut lithium niobate high-voltage sensing

DOE PAGES

Patel, N.; Branch, D. W.; Schamiloglu, E.; ...

2015-08-11

A comparison study between Y+36° and 0° X-cut lithium niobate (LiNbO 3) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y+36° crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5 μs voltage pulses tomore » both crystals, the voltage-induced shift scaled linearly with voltage. For the Y+36° cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz–100 kHz. Using the same conditions as the Y+36° cut, the 0° X-cut crystal sensed a shift of 10–273 ps for DC voltages and 189–813 ps for AC voltage application. For 5 μs voltage pulses, the 0° X-cut crystal sensed a voltage induced shift of 0.250–2 ns and the Y+36°-cut crystal sensed a time shift of 0.115–1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. Furthermore, when the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.« less

Frequency-dependent laminar electroosmotic flow in a closed-end rectangular microchannel.

PubMed

Marcos; Yang, C; Ooi, K T; Wong, T N; Masliyah, J H

2004-07-15

This article presents an analysis of the frequency- and time-dependent electroosmotic flow in a closed-end rectangular microchannel. An exact solution to the modified Navier-Stokes equation governing the ac electroosmotic flow field is obtained by using the Green's function formulation in combination with a complex variable approach. An analytical expression for the induced backpressure gradient is derived. With the Debye-Hückel approximation, the electrical double-layer potential distribution in the channel is obtained by analytically solving the linearized two-dimensional Poisson-Boltzmann equation. Since the counterparts of the flow rate and the electrical current are shown to be linearly proportional to the applied electric field and the pressure gradient, Onsager's principle of reciprocity is demonstrated for transient and ac electroosmotic flows. The time evolution of the electroosmotic flow and the effect of a frequency-dependent ac electric field on the oscillating electroosmotic flow in a closed-end rectangular microchannel are examined. Specifically, the induced pressure gradient is analyzed under effects of the channel dimension and the frequency of electric field. In addition, based on the Stokes second problem, the solution of the slip velocity approximation is presented for comparison with the results obtained from the analytical scheme developed in this study. Copyright 2004 Elsevier Inc.

Poly(sophorolipid) structural variation: effects on biomaterial physical and biological properties.

PubMed

Peng, Yifeng; Munoz-Pinto, Dany J; Chen, Mingtao; Decatur, John; Hahn, Mariah; Gross, Richard A

2014-11-10

Diacetylated lactonic sophorolipids (polyLSL[6'Ac,6″Ac]), a biosurfactant, can be efficiently polymerized by ring-opening metathesis polymerization (ROMP). In this paper, enzyme-mediated chemical transformations are developed to regioselectively modify LSL[6'Ac,6″Ac] at sophorose primary hydroxyl positions (6' and 6″). The resulting modified LSLs were polymerized to expand polyLSL structural diversity, that is, polyLSL[6'OH,6″Ac], polyLSL[6'OH,6″OH], polyLSL[6'Bu,6″Ac], polyLSL[6'N3,6″Ac], and polyLSL[6'MA,6″Ac]. Controlled placement of azide and methacrylate at sophorolipid moieties enables the use of "click" reactions to introduce bioactive groups. Thermal analyses of polyLSLs showed that the acylation pattern at sugar moieties has a remarkable effect on chain stiffness and crystallinity. Films of polyLSL[6'Ac,6″Ac], polyLSL[6'OH,6″Ac], and polyLSL[6'Bu,6″Ac] exhibited nonbrittle behaviors with compressive elastic moduli ranging from ∼1.5 to ∼4.9 MPa. PolyLSLs were cytocompatible with human mesenchymal stem cells (h-MSCs), and examination of material-induced osteogenic cell lineage progression uncovered a dependence on polyLSL substitution at sophorose 6'-sites. This research reveals opportunities to regulate polyLSL physical properties and cell response behaviors by variation in substituents at polyLSL sophorolipid moieties.

Pre-Drinking and the Temporal Gradient of Intoxication in a New Zealand Nightlife Environment.

PubMed

Cameron, Michael P; Roskruge, Matthew J; Droste, Nic; Miller, Peter G

2018-01-01

We measured changes in the average level of intoxication over time in the nighttime economy and identified the factors associated with intoxication, including pre-drinking. A random intercept sample of 320 pedestrians (105 women; 215 men) was interviewed and received breath alcohol analysis in the nighttime economy of Hamilton, New Zealand. Data were collected over a five-night period, between 7 P.M. and 2:30 A.M. Data were analyzed by plotting the moving average breath alcohol concentration (BrAC) over time and using linear regression models to identify the factors associated with BrAC. Mean BrAC was 241.5 mcg/L for the full sample; 179.7 for women and 271.7 for men, which is a statistically significant difference. Mean BrAC was also significantly higher among those who engaged in pre-drinking than those who did not. In the regression models, time of night and pre-drinking were significantly associated with higher BrAC. The effect of pre-drinking on BrAC was larger for women than for men. The average level of intoxication increases throughout the night. However, this masks a potentially important gender difference, in that women's intoxication levels stop increasing after midnight, whereas men's increase continuously through the night. Similarly, intoxication of pre-drinkers stops increasing from 11 P.M., although remaining higher than non-pre-drinkers throughout the night. Analysis of BrAC provides a more nuanced understanding of intoxication levels in the nighttime economy.

A linear magnetic motor and generator

NASA Technical Reports Server (NTRS)

Studer, P. A.

1980-01-01

In linear magnetic motor and generator suitable for remote and hostile environments, magnetic forces drive reciprocating shaft along its axis. Actuator shaft is located in center of cylindrical body and may be supported by either contacting or noncontacting bearings. When device operates as bidirectional motor, drive coil selectively adds and subtracts magnetic flux to and from flux paths, producing forces that drive actuator along axis. When actuator is driven by external reciprocating engine, device becomes ac generator.

Employees’ Organizational Identification and Affective Organizational Commitment: An Integrative Approach

PubMed Central

Stinglhamber, Florence; Marique, Géraldine; Caesens, Gaëtane; Desmette, Donatienne; Hansez, Isabelle; Hanin, Dorothée; Bertrand, Françoise

2015-01-01

Although several studies have empirically supported the distinction between organizational identification (OI) and affective commitment (AC), there is still disagreement regarding how they are related. Precisely, little attention has been given to the direction of causality between these two constructs and as to why they have common antecedents and outcomes. This research was designed to fill these gaps. Using a cross-lagged panel design with two measurement times, Study 1 examined the directionality of the relationship between OI and AC, and showed that OI is positively related to temporal change in AC, confirming the antecedence of OI on AC. Using a cross-sectional design, Study 2 investigated the mediating role of OI in the relationship between three work experiences (i.e., perceived organizational support, leader-member exchange, and job autonomy) and AC, and found that OI partially mediates the influence of work experiences on AC. Finally, Study 3 examined longitudinally how OI and AC combine in the prediction of actual turnover, and showed that AC totally mediates the relationship between OI and turnover. Overall, these findings suggest that favorable work experiences operate via OI to increase employees' AC that, in turn, decreases employee turnover. PMID:25875086

Employees' organizational identification and affective organizational commitment: an integrative approach.

PubMed

Stinglhamber, Florence; Marique, Géraldine; Caesens, Gaëtane; Desmette, Donatienne; Hansez, Isabelle; Hanin, Dorothée; Bertrand, Françoise

2015-01-01

Although several studies have empirically supported the distinction between organizational identification (OI) and affective commitment (AC), there is still disagreement regarding how they are related. Precisely, little attention has been given to the direction of causality between these two constructs and as to why they have common antecedents and outcomes. This research was designed to fill these gaps. Using a cross-lagged panel design with two measurement times, Study 1 examined the directionality of the relationship between OI and AC, and showed that OI is positively related to temporal change in AC, confirming the antecedence of OI on AC. Using a cross-sectional design, Study 2 investigated the mediating role of OI in the relationship between three work experiences (i.e., perceived organizational support, leader-member exchange, and job autonomy) and AC, and found that OI partially mediates the influence of work experiences on AC. Finally, Study 3 examined longitudinally how OI and AC combine in the prediction of actual turnover, and showed that AC totally mediates the relationship between OI and turnover. Overall, these findings suggest that favorable work experiences operate via OI to increase employees' AC that, in turn, decreases employee turnover.

Segmented AC-coupled readout from continuous collection electrodes in semiconductor sensors

DOEpatents

Sadrozinski, Hartmut F. W.; Seiden, Abraham; Cartiglia, Nicolo

2017-04-04

Position sensitive radiation detection is provided using a continuous electrode in a semiconductor radiation detector, as opposed to the conventional use of a segmented electrode. Time constants relating to AC coupling between the continuous electrode and segmented contacts to the electrode are selected to provide position resolution from the resulting configurations. The resulting detectors advantageously have a more uniform electric field than conventional detectors having segmented electrodes, and are expected to have much lower cost of production and of integration with readout electronics.

Photovoltaic system with improved DC connections and method of making same

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cioffi, Philip Michael; Todorovic, Maja Harfman; Herzog, Michael Scott

A micro-inverter assembly includes a housing having an opening formed in a bottom surface thereof, and a direct current (DC)-to-alternating current (AC) micro-inverter disposed within the housing at a position adjacent to the opening. The micro-inverter assembly further includes a micro-inverter DC connector electrically coupled to the DC-to-AC micro-inverter and positioned within the opening of the housing, the micro-inverter DC connector having a plurality of exposed electrical contacts.

Analysis and Control of Pulse-Width Modulated AC to DC Voltage Source Converters.

NASA Astrophysics Data System (ADS)

Wu, Rusong

The pulse width modulated AC to DC voltage source converter is comprehensively analyzed in the thesis. A general mathematical model of the converter is first established, which is discontinuous, time-variant and non-linear. The following three techniques are used to obtain closed form solutions: Fourier analysis, transformation of reference frame and small signal linearization. Three models, namely, a steady-state DC model, a low frequency small signal AC model and a high frequency model, are consequently developed. Finally, three solution sets, namely, the steady-state solution, various dynamic transfer functions and the high frequency harmonic components, are obtained from the three models. Two control strategies, the Phase and Amplitude Control (PAC) and a new proposed strategy, Predicted Current Control with a Fixed Switching Frequency (PCFF), are investigated. Based on the transfer functions derived from the above mentioned analysis, regulators for a closed-loop control are designed. A prototype circuit is built to experimentally verify the theoretical predictions. The analysis and experimental results show that both strategies produce nearly sinusoidal line current with unity power factor on the utility side in both rectifying and regenerating operations and concurrently provide a regulated DC output voltage on the load side. However the proposed PCFF control has a faster and improved dynamic response over the PAC control. Moreover it is also easier to be implemented. Therefore, the PCFF control is preferable to the PAC control. As an example of application, a configuration of variable DC supply under PCFF control is proposed. The quasi-optimal dynamic response obtained shows that the PWM AC to DC converter lays the foundation for building a four-quadrant, fast-dynamic system, and the PCFF control is an effective strategy for improving dynamic performances not only as applied to the AC to DC converter, but also as applied to the DC to DC chopper or other circuits.

Comparison of Optical Coherence Tomography and Scanning Laser Polarimetry Measurements in Patients with Multiple Sclerosis

PubMed Central

Quelly, Amanda; Cheng, Han; Laron, Michal; Schiffman, Jade S.; Tang, Rosa A.

2010-01-01

Purpose To compare optical coherence tomography (OCT) and scanning laser polarimetry (GDx) measurements of the retinal nerve fiber layer (RNFL) in multiple sclerosis (MS) patients with and without optic neuritis (ON). Methods OCT and GDx were performed on 68 MS patients. Qualifying eyes were divided into two groups: 51 eyes with an ON history ≥ 6 months prior (ON eyes), and 65 eyes with no history of ON (non-ON eyes). Several GDx and OCT parameters and criteria were used to define an eye as abnormal, for example, GDx nerve fiber indicator (NFI) above 20 or 30, OCT average RNFL thickness and GDx temporal-superior-nasal-inferior-temporal average (TSNIT) below 5% or 1% of the instruments’ normative database. Agreement between OCT and GDx parameters was reported as percent of observed agreement, along with the AC1 statistic. Linear regression analyses were used to examine the relationship between OCT average RNFL thickness and GDx NFI and TSNIT. Results All OCT and GDx measurements showed significantly more RNFL damage in ON than in non-ON eyes. Agreement between OCT and GDx parameters ranged from 69–90% (AC1 0.37–0.81) in ON eyes, and 52–91% (AC1 = 0.21–0.90) in non-ON eyes. Best agreement was observed between OCT average RNFL thickness (P < 0.01) and NFI (>30) in ON eyes (90%, AC1 = 0.81), and between OCT average RNFL thickness (P < 0.01) and GDx TSNIT average (P < 0.01) in non-ON eyes (91%, AC1 = 0.90). In ON eyes, the OCT average RNFL thickness showed good linear correlation with NFI (R2 = 0.69, P < 0.0001) and TSNIT (R2 = 0.55, P < 0.0001). Conclusions OCT and GDx show good agreement and can be useful in detecting RNFL loss in MS/ON eyes. PMID:20495500

Assay of mucins in human tear fluid.

PubMed

Spurr-Michaud, Sandra; Argüeso, Pablo; Gipson, Ilene

2007-05-01

Mucin genes, both secreted (MUC2, MUC5AC, MUC5B, MUC7) and membrane associated (MUC1, MUC4, MUC16), have been reported to be expressed by ocular surface epithelia. The purpose of this study was to comprehensively assay the mucin content of human tear fluid using multiple antibodies for each mucin and to develop a sensitive, semi-quantitative method for the assay of mucins in tears. Tear washes were obtained by instillation of saline onto the ocular surface, followed by collection from the inferior fornix. Tear proteins were separated in 1% agarose gels, transferred to nitrocellulose membrane by vacuum blotting and probed with multiple antibodies recognizing MUC1, MUC2, MUC4, MUC5AC, MUC5B, MUC7 and MUC16. Binding was detected using chemiluminescence, and quantity was determined by densitometry. Serial dilutions of pooled tears from normal individuals were assayed to determine the linear range of detectability. MUC1, MUC4, MUC16, MUC5AC and low levels of MUC2 were consistently detected in human tear fluid, while MUC5B and MUC7 were not. Use of several antibodies recognizing different epitopes on the same mucin confirmed these findings. The antibodies to mucins bound to serial dilutions of tears in a linear fashion (r2 > 0.9), indicating the feasibility of semi-quantitation. MUC5AC in tear fluid had an increased electrophoretic mobility compared to MUC5AC isolated from conjunctival tissue. This study provides clear evidence that the mucin component of tears is a mixture of secreted and shed membrane-associated mucins, and for the first time demonstrates MUC16 in tear fluid. Immunoblots of tears using agarose gel electrophoresis and chemiluminescence detection provide a semi-quantitative assay for mucin protein that will be useful for comparisons with tears from diseased eyes or after pharmacological intervention.

Assay of Mucins in Human Tear Fluid

PubMed Central

Spurr-Michaud, Sandra; Argüeso, Pablo; Gipson, Ilene

2007-01-01

Mucin genes, both secreted (MUC2, MUC5AC, MUC5B, MUC7) and membrane associated (MUC1, MUC4, MUC16), have been reported to be expressed by ocular surface epithelia. The purpose of this study was to comprehensively assay the mucin content of human tear fluid using multiple antibodies for each mucin and to develop a sensitive, semi-quantitative method for the assay of mucins in tears. Tear washes were obtained by instillation of saline onto the ocular surface, followed by collection from the inferior fornix. Tear proteins were separated in 1% agarose gels, transferred to nitrocellulose membrane by vacuum blotting and probed with multiple antibodies recognizing MUC1, MUC2, MUC4, MUC5AC, MUC5B, MUC7 and MUC16. Binding was detected using chemiluminescence, and quantity was determined by densitometry. Serial dilutions of pooled tears from normal individuals were assayed to determine the linear range of detectability. MUC1, MUC4, MUC16, MUC5AC and low levels of MUC2 were consistently detected in human tear fluid, while MUC5B and MUC7 were not. Use of several antibodies recognizing different epitopes on the same mucin confirmed these findings. The antibodies to mucins bound to serial dilutions of tears in a linear fashion (r2 >0.9), indicating the feasibility of semi-quantitation. MUC5AC in tear fluid had an increased electrophoretic mobility compared to MUC5AC isolated from conjunctival tissue. This study provides clear evidence that the mucin component of tears is a mixture of secreted and shed membrane-associated mucins, and for the first time demonstrates MUC16 in tear fluid. Immunoblots of tears using agarose gel electrophoresis and chemiluminescence detection provide a semi-quantitative assay for mucin protein that will be useful for comparisons with tears from diseased eyes or after pharmacological intervention. PMID:17399701

Effect of Dimension and Shape of Magnet on the Performance AC Generator with Translation Motion

NASA Astrophysics Data System (ADS)

Indriani, A.; Dimas, S.; Hendra

2018-02-01

The development of power plants using the renewable energy sources is very rapid. Renewable energy sources used solar energy, wind energy, ocean wave energy and other energy. All of these renewable energy sources require a processing device or a change of motion system to become electrical energy. One processing device is a generator which have work principle of converting motion (mechanical) energy into electrical energy with rotary shaft, blade and other motion components. Generator consists of several types of rotation motion and linear motion (translational). The generator have components such as rotor, stator and anchor. In the rotor and stator having magnet and winding coil as an electric generating part of the electric motion force. Working principle of AC generator with linear motion (translation) also apply the principle of Faraday that is using magnetic induction which change iron magnet to produce magnetic flux. Magnetic flux is captured by the stator to be converted into electrical energy. Linear motion generators consist of linear induction machine, wound synchronous machine field, and permanent magnet synchronous [1]. Performance of synchronous generator of translation motion is influenced by magnet type, magnetic shape, coil winding, magnetic and coil spacing and others. In this paper focus on the neodymium magnet with varying shapes, number of coil windings and gap of magnetic distances. This generator work by using pneumatic mechanism (PLTGL) for power plants system. Result testing of performance AC generator translation motion obtained that maximum voltage, current and power are 63 Volt for diameter winding coil 0.15 mm, number of winding coil 13000 and distance of magnet 20 mm. For effect shape of magnet, maximum voltage happen on rectangle magnet 30x20x5 mm with 4.64 Volt. Voltage and power on effect of diameter winding coil is 14.63 V and 17.82 W at the diameter winding coil 0.7 and number of winding coil is 1260 with the distance of magnet 25 mm.

Isolated abdominal circumference < 5% or estimated fetal weight 10 to 19% as predictors of small for gestational age infants.

PubMed

Turitz, Amy L; Quant, Hayley; Schwartz, Nadav; Elovitz, Michal; Bastek, Jamie A

2014-06-01

To determine whether (1) isolated fetal abdominal circumference < 5% (AC5) in absence of growth restriction (estimated fetal weight < 10% [EFW10]) or (2) borderline fetal growth 10 to 19% (EFW10-19) predicts subsequent fetal and/or neonatal growth restriction. The authors performed a retrospective cohort study (January 2008 to December 2011) of women with singleton pregnancies between 26 and 36 weeks who had ≥ 1 growth ultrasound. Univariable and multivariable analyses were performed to determine the association between isolated AC5 or EFW10-19 with both subsequent sonographic diagnosis of EFW10 and neonatal diagnosis of small for gestational age (SGA). Test characteristics were calculated. Out of the 10,642 pregnancies, prevalence of isolated AC5, EFW10-19, EFW10, and SGA were as follows: AC5, 5.31%; EFW10-19, 13.30%; EFW10, 7.95%; and SGA, 17.63%. While screening for SGA using EFW10 alone would miss 68.34% of SGA neonates, using isolated AC5 would identify an additional 16.15% of SGA neonates with a 3.7% false positive rate. Using EFW10-19 would identify an additional 40.20% of SGA neonates with a 9.0% false positive rate. Fetuses with isolated AC5 or EFW10-19 are at an increased risk of growth restriction. Using isolated AC5 or composite EFW10-19 would identify SGA neonates that are missed using conventional sonographic definitions of growth restriction alone. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Predischarge screening for chronic obstructive pulmonary disease in patients with acute coronary syndrome and smoking history.

PubMed

Campo, Gianluca; Pavasini, Rita; Barbetta, Carlo; Maietti, Elisa; Mascetti, Susanna; Biscaglia, Simone; Zaraket, Fatima; Spitaleri, Giosafat; Gallo, Francesco; Tonet, Elisabetta; Papi, Alberto; Ferrari, Roberto; Contoli, Marco

2016-11-01

Several studies suggested that chronic obstructive pulmonary disease (COPD) is largely underdiagnosed in patients with acute coronary syndrome (ACS) contributing to further affect clinical outcome. Our aim was to validate a screening procedure to identify, in ACS patients, those with negligible risk of undiagnosed COPD. From December 2014 to August 2015, 169 ACS patients with smoking history underwent screening procedure. Screening procedure combined peak expiratory flow rate (PEFR, defined as positive if <80% of predicted) and respiratory health status questionnaire (RHSQ, defined as positive if >19.5 points). The screening was considered negative if both tests provided negative results, positive if both were positive, uncertain in presence of discrepancy. Spirometry was planned after 2months to identify or not the presence of irreversible airflow obstruction (undiagnosed COPD). The primary endpoint was the negative predictive value of screening for undiagnosed COPD. Overall, 137 (81%) patients received spirometry (final study population). Screening was negative, uncertain and positive in 58 (42%), 46 (34%) and 33 (24%) patients, respectively. We found undiagnosed COPD in 39 (29%) patients. Only 3 patients with negative screening showed undiagnosed COPD. Negative screening showed the best ability to discriminate patients without COPD (negative predictive value 95%). Two-month health status in patients with undiagnosed COPD was significantly poor. Undiagnosed COPD is relatively frequent in ACS patients with smoking history and a simple screening procedure including PEFR and RHSQ can be administered before hospital discharge to discriminate those at negligible risk of undiagnosed COPD (ClinicalTrials.gov, NCT02324660). Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Diagnostic value of heart-type fatty acid binding protein determined by the rapid qualitative chromatographic immunoassay method for the detection of minor myocardial damage in patients presenting with non-ST elevation acute coronary syndrome.

PubMed

Çavuşoğlu, Yüksel; Gök, Bülent; Demirüstü, Canan; Birdane, Alparslan; Görenek, Bülent; Ata, Necmi

2012-11-01

The aim of this prospective study was to evaluate the diagnostic value of heart-type fatty acid binding protein (H-FABP) determined by qualitative immunoassay method for the detection of minor myocardial damage (MMD) in patients with non-ST elevation acute coronary syndrome (NSTE-ACS). The study consisted of 62 patients with NSTE-ACS. Cardiac troponin I (cTnI) and creatine kinase MB isoenzyme (CK-MB) values were measured at arrival. Myoglobin and H-FABP were obtained if cTnI level was found to be elevated. A control group included 20 subjects with normal cTnI and CK-MB values. H-FABP was determined by a rapid qualitative immunochromatographic test. Patients were classified as MMD-ACS group if they had abnormal cTnI and normal CK-MB (n=24) and as NSTEMI-ACS group if they had elevated both cTnI and CK-MB (n=38). The diagnostic accuracy of H-FABP for minor myocardial damage was determined using ROC analysis. The sensitivity of the H-FABP was significantly higher for NSTEMI-ACS than for MMD-ACS (44.7% vs 0%, p<0.001) and its specificity was 95% for both groups. The diagnostic efficacy rates for myoglobin and H-FABP were 75% and 43% for MMD-ACS, 74% and 62% for NSTEMI-ACS. Positive predictive value for H-FABP and myoglobin were found to be 0% and 80.8% in MMD-ACS, 94% and 87% in NSTEMI-ACS and negative predictive value was 44% and 69.5% in MMD-ACS, 47.5% and 59% in NSTEMI-ACS, respectively. AUC for myoglobin was significantly greater than that for H-FABP in MMD-ACS group (0.754 vs 0.525, p=0.027). The sensitivity of the H-FABP was significantly higher in patients with >3-fold increase in cTnI than those with <3-fold increase in cTnI (46.8% vs. 6.7%, p<0.001). A positive correlation was found between the magnitude of cTnI rise and H-FABP results (r=0.45, p<0.001). H-FABP determined by the rapid qualitative immunochromatographic test has almost similar diagnostic value to that of myoglobin for identifying NSTEMI-ACS, however, does not seem to represent diagnostic potential for the detection of MMD.

Synthesis and Pharmacology of α/β(3)-Peptides Based on the Melanocortin Agonist Ac-His-dPhe-Arg-Trp-NH2 Sequence.

PubMed

Singh, Anamika; Tala, Srinivasa R; Flores, Viktor; Freeman, Katie; Haskell-Luevano, Carrie

2015-05-14

The melanocortin-3 and -4 receptors are expressed in the brain and play key roles in regulating feeding behavior, metabolism, and energy homeostasis. In the present study, incorporation of β(3)-amino acids into a melanocortin tetrapeptide template was investigated. Four linear α/β(3)-hybrid tetrapeptides were designed with the modifications at the Phe, Arg, and Trp residues in the agonist sequence Ac-His-dPhe-Arg-Trp-NH2. The most potent mouse melanocortin-4 receptor (mMC4R) agonist, Ac-His-dPhe-Arg-β(3)hTrp-NH2 (8) showed 35-fold selectivity versus the mMC3R. The study presented here has identified a new template with heterogeneous backbone for designing potent and selective melanocortin receptor ligands.

Synthesis and Pharmacology of α/β3-Peptides Based on the Melanocortin Agonist Ac-His-dPhe-Arg-Trp-NH2 Sequence

PubMed Central

2015-01-01

The melanocortin-3 and -4 receptors are expressed in the brain and play key roles in regulating feeding behavior, metabolism, and energy homeostasis. In the present study, incorporation of β3-amino acids into a melanocortin tetrapeptide template was investigated. Four linear α/β3-hybrid tetrapeptides were designed with the modifications at the Phe, Arg, and Trp residues in the agonist sequence Ac-His-dPhe-Arg-Trp-NH2. The most potent mouse melanocortin-4 receptor (mMC4R) agonist, Ac-His-dPhe-Arg-β3hTrp-NH2 (8) showed 35-fold selectivity versus the mMC3R. The study presented here has identified a new template with heterogeneous backbone for designing potent and selective melanocortin receptor ligands. PMID:26005535

Small-Signal Dynamic Analysis of LCC-HVDC with STATCOM at the Inverter Busbar

NASA Astrophysics Data System (ADS)

Liu, Dong; Jiang, Wen; Guo, Chunyi; Rehman, Atiq Ur; Zhao, Chengyong

2018-01-01

This paper develops a linearized small-signal dynamic model of a Line-Commutated-Converter based HVDC (LCC-HVDC) system with STATCOM at the inverter busbar, and validates its accuracy by comparing time-domain responses from small-signal model and PSCAD-based simulation results. Considering the potential impact of Phase-Locked-Loop (PLL) parameters on the study system and the close connection of STATCOM and LCC inverter station at AC busbar, this paper investigates the impact of PLL gains and AC voltage control parameters of STATCOM on the system small-signal stability. The studies show that (i) the PLL gain has highly impact on the study system and smaller PLL gains are preferable; (ii) larger values of both the proportional gain and the integral gain of AC voltage controller of STATCOM could result in oscillation/instability of the system.

Associations between psychological constructs and cardiac biomarkers following acute coronary syndrome

PubMed Central

Celano, Christopher M.; Beale, Eleanor E.; Beach, Scott R.; Belcher, Arianna M.; Suarez, Laura; Motiwala, Shweta R.; Gandhi, Parul U.; Gaggin, Hanna; Januzzi, James L.; Healy, Brian C.; Huffman, Jeff C.

2016-01-01

Objective Psychological constructs are associated with cardiovascular health, but the biological mechanisms mediating these relationships are unknown. We examined relationships between psychological constructs and markers of inflammation, endothelial function, and myocardial strain in a cohort of post-acute coronary syndrome (ACS) patients. Methods Participants (N=164) attended study visits 2 weeks and 6 months post-ACS. During these visits, they completed self-report measures of depressive symptoms, anxiety, optimism, and gratitude, and blood samples were collected for measurement of biomarkers reflecting inflammation, endothelial function, and myocardial strain. Generalized estimating equations and linear regression analyses were performed to examine concurrent and prospective relationships between psychological constructs and biomarkers. Results In concurrent analyses, depressive symptoms were associated with elevated markers of inflammation (interleukin-17: β=.047, 95% confidence interval [.010, .083]), endothelial dysfunction (endothelin-1: β=.020, [.004, .037]), and myocardial strain (N-terminal pro-B-type natriuretic peptide: β=.045, [.008, .083]), independent of age, sex, medical variables, and anxiety, while anxiety was not associated with these markers in multivariable adjusted models. Optimism and gratitude were associated with lower levels of markers of endothelial dysfunction (endothelin-1: gratitude: β=−.009, [−.017, −.001]; optimism: β=−.009, [−.016, −.001]; soluble intercellular adhesion molecule-1: gratitude: β=−.007, [−.014, −.000]), independent of depressive and anxiety symptoms. Psychological constructs at 2 weeks were not prospectively associated with biomarkers at 6 months. Conclusions Depressive symptoms were associated with more inflammation, myocardial strain, and endothelial dysfunction in the 6 months post-ACS, while positive psychological constructs were linked to better endothelial function. Larger, prospective studies may clarify the directionality of these relationships. PMID:27749683

Screening length and quantum capacitance in graphene by scanning probe microscopy.

PubMed

Giannazzo, F; Sonde, S; Raineri, V; Rimini, E

2009-01-01

A nanoscale investigation on the capacitive behavior of graphene deposited on a SiO2/n(+) Si substrate (with SiO2 thickness of 300 or 100 nm) was carried out by scanning capacitance spectroscopy (SCS). A bias V(g) composed by an AC signal and a slow DC voltage ramp was applied to the macroscopic n(+) Si backgate of the graphene/SiO(2)/Si capacitor, while a nanoscale contact was obtained on graphene by the atomic force microscope tip. This study revealed that the capacitor effective area (A(eff)) responding to the AC bias is much smaller than the geometrical area of the graphene sheet. This area is related to the length scale on which the externally applied potential decays in graphene, that is, the screening length of the graphene 2DEG. The nonstationary charges (electrons/holes) induced by the AC potential spread within this area around the contact. A(eff) increases linearly with the bias and in a symmetric way for bias inversion. For each bias V(g), the value of A(eff) is related to the minimum area necessary to accommodate the not stationary charges, according to the graphene density of states (DOS) at V(g). Interestingly, by decreasing the SiO(2) thickness from 300 to 100 nm, the slope of the A(eff) versus bias curve strongly increases (by a factor of approximately 50). The local quantum capacitance C(q) in the contacted graphene region was calculated starting from the screening length, and the distribution of the values of C(q) for different tip positions was obtained. Finally the lateral variations of the DOS in graphene was determined.

Impact of divalent metal ions on regulation of adenylyl cyclase isoforms by forskolin analogs.

PubMed

Erdorf, Miriam; Mou, Tung-Chung; Seifert, Roland

2011-12-01

Mammalian membranous adenylyl cyclases (mACs) play an important role in transmembrane signalling events in almost every cell and represent an interesting drug target. Forskolin (FS) is an invaluable research tool, activating AC isoforms 1-8. However, there is a paucity of AC isoform-selective FS analogs. Therefore, we examined the effects of FS and six FS derivatives on recombinant ACs 1, 2 and 5, representing members of different mAC families. Correlations of the pharmacological properties of the different AC isoforms revealed pronounced differences between ACs 1, 2 and 5. Additionally, potencies and efficacies of FS derivatives changed for any given AC isoform, depending on the metal ion, Mg(2+) or Mn(2+). The most striking effects of Mg(2+) and Mn(2+) on the diterpene profile were observed for AC2 where the large inhibitory effect of BODIPY-FS in the presence of Mg(2+) was considerably reduced in the presence of Mn(2+). Sequence alignment and docking experiments confirmed an exceptional position of AC2 compared to ACs 1 and 5 with respect to the structural environment of the catalytic core and cation-dependent diterpene effects. In conclusion, mAC isoforms 1, 2 and 5 exhibit a distinct pharmacological diterpene profile, depending on the divalent cation present. mAC crystal structures and modelling/docking studies provided an explanation for the pharmacological differences between the AC isoforms. Our study constitutes an important step towards the development of isoform-specific diterpenes exhibiting stimulatory or inhibitory effects. Copyright © 2011 Elsevier Inc. All rights reserved.

Circulating Myeloid‐Related Protein–8/14 is Related to Thromboxane‐Dependent Platelet Activation in Patients With Acute Coronary Syndrome, With and Without Ongoing Low‐Dose Aspirin Treatment

PubMed Central

Santilli, Francesca; Paloscia, Leonardo; Liani, Rossella; Di Nicola, Marta; Di Marco, Massimo; Lattanzio, Stefano; La Barba, Sara; Pascale, Silvia; Mascellanti, Marco; Davì, Giovanni

2014-01-01

Background Platelet activation is involved in acute coronary syndromes (ACS). Incomplete suppression by low‐dose aspirin treatment of thromboxane (TX) metabolite excretion (urinary 11‐dehydro‐TXB2) is predictive of vascular events in high‐risk patients. Myeloid‐related protein (MRP)‐8/14 is a heterodimer secreted on activation of platelets, monocytes, and neutrophils, regulating inflammation and predicting cardiovascular events. Among platelet transcripts, MRP‐14 has emerged as a powerful predictor of ACS. Methods and Results We enrolled 68 stable ischemic heart disease (IHD) and 63 ACS patients, undergoing coronary angiography, to evaluate whether MRP‐8/14 release in the circulation is related to TX‐dependent platelet activation in ACS and IHD patients and to residual TX biosynthesis in low‐dose aspirin–treated ACS patients. In ACS patients, plasma MRP‐8/14 and urinary 11‐dehydro‐TXB2 levels were linearly correlated (r=0.651, P<0.001) but significantly higher than those in IHD patients (P=0.012, P=0.044) only among subjects not receiving aspirin. In aspirin‐treated ACS patients, MRP‐8/14 and 11‐dehydro‐TXB2 were lower versus those not receiving aspirin (P<0.001) and still significantly correlated (r=0.528, P<0.001). Higher 11‐dehydro‐TXB2 significantly predicted higher MRP‐8/14 in both all ACS patients and ACS receiving aspirin (P<0.001, adj R2=0.463 and adj R2=0.497) after multivariable adjustment. Conversely, plasma MRP‐8/14 (P<0.001) and higher urinary 8‐iso‐prostaglandin F2α (P=0.050) levels were significant predictors of residual, on‐aspirin, TX biosynthesis in ACS (adjusted R2=0.384). Conclusions Circulating MRP‐8/14 is associated with TX‐dependent platelet activation in ACS, even during low‐dose aspirin treatment, suggesting a contribution of residual TX to MRP‐8/14 shedding, which may further amplify platelet activation. Circulating MRP‐8/14 may be a target to test different antiplatelet strategies in ACS. PMID:25037196

Segmented media and medium damping in microwave assisted magnetic recording

NASA Astrophysics Data System (ADS)

Bai, Xiaoyu; Zhu, Jian-Gang

2018-05-01

In this paper, we present a methodology of segmented media stack design for microwave assisted magnetic recording. Through micro-magnetic modeling, it is demonstrated that an optimized media segmentation is able to yield high signal-to-noise ratio even with limited ac field power. With proper segmentation, the ac field power could be utilized more efficiently and this can alleviate the requirement for medium damping which has been previously considered a critical limitation. The micro-magnetic modeling also shows that with segmentation optimization, recording signal-to-noise ratio can have very little dependence on damping for different recording linear densities.

Evaluation Of Different Power Conditioning Options For Stirling Generators

NASA Astrophysics Data System (ADS)

Garrigos, A.; Blanes, J. M.; Carrasco, J. A.; Maset, E.; Montalban, G.; Ejea, J.; Ferreres, A.; Sanchis, E.

2011-10-01

Free-piston Stirling engines are an interesting alternative for electrical power systems, especially in deep space missions where photovoltaic systems are not feasible. This kind of power generators contains two main parts, the Stirling machine and the linear alternator that converts the mechanical energy from the piston movement to electrical energy. Since the generated power is in AC form, several aspects should be assessed to use such kind of generators in a spacecraft power system: AC/DC topologies, power factor correction, power regulation techniques, integration into the power system, etc. This paper details power generator operation and explores different power conversion approaches.

Comparative ELM study between the observation by ECEI and linear/nonlinear simulation in the KSTAR plasmas

NASA Astrophysics Data System (ADS)

Kim, Minwoo; Park, Hyeon K.; Yun, Gunsu; Lee, Jaehyun; Lee, Jieun; Lee, Woochang; Jardin, Stephen; Xu, X. Q.; Kstar Team

2015-11-01

The modeling of the Edge-localized-mode (ELM) should be rigorously pursued for reliable and robust ELM control for steady-state long-pulse H-mode operation in ITER as well as DEMO. In the KSTAR discharge #7328, a linear stability of the ELMs is investigated using M3D-C1 and BOUT + + codes. This is achieved by linear simulation for the n = 8 mode structure of the ELM observed by the KSTAR electron cyclotron emission imaging (ECEI) systems. In the process of analysis, variations due to the plasma equilibrium profiles and transport coefficients on the ELM growth rate are investigated and simulation results with the two codes are compared. The numerical simulations are extended to nonlinear phase of the ELM dynamics, which includes saturation and crash of the modes. Preliminary results of the nonlinear simulations are compared with the measured images especially from the saturation to the crash. This work is supported by NRF of Korea under contract no. NRF-2014M1A7A1A03029865, US DoE by LLNL under contract DE-AC52-07NA27344 and US DoE by PPPL under contract DE-AC02-09CH11466.

A Technique for Estimating the Surface Conductivity of Single Molecules

NASA Astrophysics Data System (ADS)

Bau, Haim; Arsenault, Mark; Zhao, Hui; Purohit, Prashant; Goldman, Yale

2007-11-01

When an AC electric field at 2MHz was applied across a small gap between two metal electrodes elevated above a surface, rhodamine-phalloidin-labeled actin filaments were attracted to the gap and became suspended between the two electrodes. The variance of each filament's horizontal, lateral displacement was measured as a function of electric field intensity and position along the filament. The variance significantly decreased as the electric field intensity increased. Hypothesizing that the electric field induces electroosmotic flow around the filament that, in turn, induces drag on the filament, which appears as effective tension, we estimated the tension using a linear, Brownian dynamic model. Based on the tension, we estimated the filament's surface conductivity. Our experimental method provides a novel means for trapping and manipulating biological filaments and for probing the surface conductance and mechanical properties of single polymers.

Evidence of Strict Stereospecificity in the Structure of sn-1,2-Diacyl-3-Acetyl-Glycerols from Euonymus maximowiczianus Seeds Using Nuclear Magnetic Resonance Spectroscopy.

PubMed

Sidorov, Roman A; Shashkov, Alexander S; Solovyev, Pavel A; Gorshkova, Elena N; Tsydendambaev, Vladimir D

2018-05-02

Asymmetric, optically active sn-1,2-diacyl-3-acetyl-glycerols (AcDAG) have been known to scientists for several decades. However, to date, the problem of their structure has not been definitely resolved, which has led to a vast diversity of terms used for their designation in the literature. Using two-dimensional nuclear magnetic resonance, we have investigated AcDAG from the mature seeds of Euonymus maximowiczianus, from which we have been able to both identify a correlation of the methyl group in acetic acid residue with protons at the carbon atom at sn-3 position in the glycerol residue of the AcDAG molecule and, for the first time, demonstrate that this correlation is observed exclusively with one carbon atom at the α-position, but not with two as would have been expected in case of a racemic mixture. Moreover, results of our analysis of AcDAG isolated from the seeds of E. maximowiczianus directly confirm that diacylglycerol-3-acetyl-transferase is responsible for their biosynthesis, which reveals a strict specificity not only to acetyl-CoA as one of the substrates but also to the sn-3-position of the glycerol residue in sn-1,2-diacylglycerol during their biosynthesis. © 2018 AOCS.

Student Observations of Double Star Delta Orionis (STFA 14 AC)

NASA Astrophysics Data System (ADS)

Estrada, Reed; Aguilera, Sophia; Bowden, Sam; Gillette, Travis; Givens, Jalynn; Reder, Gabriel; Rhoades, Breauna; Sharpe, Scott; Shattles, Jenna; Cha, Brendon; Do, Vicky; Ewing, Malachi; Kiamco, Alex Junior; Nelms, Brenda; Peña, Emilie; Maricarmen, Richard; Thielen, Austin

2018-01-01

A group of eight eighth graders and eight high schoolers studied the double star STFA 14 AC. They used the procedure from Argyle's book to get the separation and position angle for the double star. The students used a Celestron C8 Schmidt-Cassegrain telescope with a Baader Planetarium microguide eyepiece with similar markings to a Celestron Eyepiece. The students determined the separation to be 56 arcseconds and the position angle to be 4.19°. They compared their results to the Washington Double Star Catalog and found that they had a 2.88 arcseconds difference in separation and a 2.19° in position angle.

An examination of the relationship of interpersonal influences with walking and biking to work.

PubMed

Campbell, Matthew E; Bopp, Melissa

2013-01-01

Active commuting (AC) to the workplace is a successful strategy for incorporating more physical activity into daily life and is associated with health benefits. The purpose of this study was to understand the relationship between interpersonal influences and AC. A cross-sectional online survey was delivered to workplaces in the mid-Atlantic region. A volunteer convenience sample of adults (N = 1234) completed questions about demographics, number of times per week actively commuting, spouse and coworker AC patterns, and spousal and coworker normative beliefs for AC. Basic descriptive and frequencies described the sample; bivariate correlations examined the relationship between AC and spouse and coworker variables. A multivariate regression analysis predicted the variance in AC with interpersonal independent variables. The sample was primarily middle-aged, white (92.7%), female (67.9%), and well-educated (83.3% college graduate or higher). Of those surveyed, 20.3% report AC to work at least once per week by means of walking or biking. The number of times per week of AC for spouse (P < .001) and coworkers (P = .006) and AC norms for spouse (P < .001) and coworker (P < .001) were positively related to AC. The multivariate regression model accounted for 37.9% of the variance in AC (F = 101.83, df = 4, P < .001). This study demonstrates that interpersonal influences are significantly related to actively commuting to work. Future interventions targeting AC should consider these interpersonal influences in addition to individual and environmental influences that have been previously documented.

Modeling AC ripple currents in HTS coated conductors by integral equations

NASA Astrophysics Data System (ADS)

Grilli, Francesco; Xu, Zhihan

2016-12-01

In several HTS applications, the superconducting tapes experience the simultaneous presence of DC and AC excitations. For example in high-current DC cables, where the transport current is not perfectly constant, but it exhibits some ripples at different frequencies introduced by the rectification process (AC-DC conversion). These ripples give rise to dissipation, whose magnitude and possible influence on the device's cooling requirements need to be evaluated. Here we report a study of the AC losses in a HTS coated conductor subjected to DC currents and AC ripples simultaneously. The modeling approach is based on an integral equation method for thin superconductors: the superconducting tape is modeled as a 1-D object with a non-linear resistivity, which includes the dependence of the critical current density Jc on the magnetic field. The model, implemented in a commercial finite-element program, runs very fast (the simulation of one AC cycle typically takes a few seconds on standard desktop workstation): this allows simulating a large number of cycles and estimating when the AC ripple losses stabilize to a constant value. The model is used to study the influence of the flux creep power index n on the stabilization speed and on the AC loss values, as well as the effect of using a field-dependent Jc instead of a constant one. The simulations confirm that the dissipation level should not be a practical concern in HTS DC cables. At the same time, however, they reveal a strong dependence of the results upon the power index n and the form of Jc , which spurs the question whether the power-law is the most suitable description of the superconductor's electrical behavior for this kind of analysis.

Predictors of long-term adherence to continuous positive airway pressure in patients with obstructive sleep apnoea and acute coronary syndrome

PubMed Central

Florés, Marina; Martinez-Alonso, Montserrat; Sánchezde-la-Torre, Alicia; Aldomà, Albina; Galera, Estefania; Barbé, Ferran; Sánchezde-la-Torre, Manuel

2018-01-01

Background Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnoea (OSA), but an evaluation of CPAP adherence is rarely carried out among patients with acute coronary syndrome (ACS). The goals of the study are to analyse long-term adherence and identify the predictors of non-compliance with CPAP treatment for patients with non-sleepy OSA and ACS. Methods This is an ancillary study of the ISAACC study, which is a multicentre, prospective, open-label, parallel, randomized, and controlled trial (NCT01335087) in patients with hospital admission for ACS. For the purpose of this study, only non-sleepy patients with moderate or severe OSA and randomized to receive CPAP treatment were analysed (n=357). Non-compliance was defined as CPAP dropout or average cumulative CPAP use of <4 hours/night. Multivariable logistic regression analysis was performed to identify predictors of CPAP adherence. Results Adherence to treatment was 35.3% at 12 months. According to the unadjusted analysis, higher apnoea-hypopnea index (AHI) (P<0.001) and oxygen desaturation index (ODI) (P=0.001) were associated with a lower risk of non-compliance. Multivariable logistic regression analysis showed that high AHI (P=0.0051), high amounts of smoking pack-year (P=0.0170), and long intensive care unit (ICU) stays (P=0.0263) were associated with lower odds of non-compliance. It also showed a significant interaction between ACS history and age (P=0.0131), such that young patients with their first ACS showed significantly lower odds of CPAP non-compliance than patients with recurrent ACS and significantly lower odds of CPAP non-compliance were associated with ageing only in patients with recurrent ACS. Conclusions Protective factors against non-compliance with CPAP treatment in non-sleepy patients with ACS were illness severity (high values of AHI or ICU stay length) or smoking amount. Patients with no previous history of ACS showed lower odds of CPAP non-compliance than patients with a recurrent ACS with younger age. PMID:29445536

Dissimilarity of increased phosphatidylserine-positive microparticles and associated coagulation activation in acute coronary syndromes.

PubMed

Liu, Yan; He, Zhangxiu; Zhang, Yan; Dong, Zengxiang; Bi, Yayan; Kou, Junjie; Zhou, Jin; Shi, Jialan

2016-08-01

We evaluated cellular origin, numbers, and procoagulant activity of phosphatidylserine-positive microparticles (MPs) among subgroups in acute coronary syndromes (ACS). Parameters were measured on admission, days 1 (within 24 h of admission), 2, 3, and 7. All ST-elevated myocardial infarction (STEMI) patients presented more than 3 h from symptom onset and received fibrinolysis treatment; controls included unstable angina and non-STEMI patients as well as healthy controls. Phosphatidylserine-positive MPs were detected by flow cytometry, whereas procoagulant activity was assessed by coagulation time, purified coagulation complex assays, and fibrin formation. MP-induced fibrins were visualized by confocal microscopy. On admission, the total MP count was ∼2.5-fold higher in the ACS groups compared with the healthy controls (P<0.05), primarily originating from platelets and endothelial cells, and there were no significant differences among ACS subgroups. Specifically, leukocyte-derived and erythrocyte-derived MPs were higher in the STEMI group compared with unstable angina and non-STEMI groups (both P<0.05). Further, MPs from the ACS groups reduced coagulation time by 27.5% and induced intrinsic and extrinsic FXase, prothrombinase, and fibrin formation by 2.8-, 2.3-, 2.5-, and 1.7-fold, respectively (P<0.05 for all), whereas blocking phosphatidylserine with lactadherin inhibited ∼70% of procoagulant activity. MP number and concomitant coagulation decreased significantly by day 2 and continued to decrease gradually during the recovery period. This study shows that MP characteristics from circulating blood may be used as prognostic indicators to reflect the origin cell of activation and thrombophilic states found in ACS subgroups.

Multilayered Regulation of Ethylene Induction Plays a Positive Role in Arabidopsis Resistance against Pseudomonas syringae.

PubMed

Guan, Rongxia; Su, Jianbin; Meng, Xiangzong; Li, Sen; Liu, Yidong; Xu, Juan; Zhang, Shuqun

2015-09-01

Ethylene, a key phytohormone involved in plant-pathogen interaction, plays a positive role in plant resistance against fungal pathogens. However, its function in plant bacterial resistance remains unclear. Here, we report a detailed analysis of ethylene induction in Arabidopsis (Arabidopsis thaliana) in response to Pseudomonas syringae pv tomato DC3000 (Pst). Ethylene biosynthesis is highly induced in both pathogen/microbe-associated molecular pattern (PAMP)-triggered immunity and effector-triggered immunity (ETI), and the induction is potentiated by salicylic acid (SA) pretreatment. In addition, Pst actively suppresses PAMP-triggered ethylene induction in a type III secretion system-dependent manner. SA potentiation of ethylene induction is dependent mostly on MITOGEN-ACTIVATED PROTEIN KINASE6 (MPK6) and MPK3 and their downstream ACS2 and ACS6, two type I isoforms of 1-aminocyclopropane-1-carboxylic acid synthases (ACSs). ACS7, a type III ACS whose expression is enhanced by SA pretreatment, is also involved. Pst expressing the avrRpt2 effector gene (Pst-avrRpt2), which is capable of triggering ETI, induces a higher level of ethylene production, and the elevated portion is dependent on SALICYLIC ACID INDUCTION DEFICIENT2 and NONEXPRESSER OF PATHOGENESIS-RELATED GENE1, two key players in SA biosynthesis and signaling. High-order ACS mutants with reduced ethylene induction are more susceptible to both Pst and Pst-avrRpt2, demonstrating a positive role of ethylene in plant bacterial resistance mediated by both PAMP-triggered immunity and ETI. © 2015 American Society of Plant Biologists. All Rights Reserved.

Functioned silver nanoparticle loaded activated carbon for the recovery of bioactive molecule from bacterial fermenter for its bactericidal activity

NASA Astrophysics Data System (ADS)

Arivizhivendhan, Villalan; Mahesh, Mannacharaju; Boopathy, Ramasamy; Karthikeyan, Sekar; Mary, Rathanasamy Regina; Sekaran, Ganesan

2018-01-01

A novel continuous production and extraction of bacterial bioactive prodigiosin (PG) from fermented using silver nanoparticle impregnated functioned activated carbon composite is proposed for cost-effective and ecofriendly microbial technique. Hence, in this investigation silver nanoparticle was impregnated onto functioned activated carbon ([AC]F) as a support matrix and to enable the separation of PG conjugated silver nanoparticle from the fermented medium. A laboratory scale experiment was carried out to evaluate the continuous production and recovery of PG using [AC@Ag]F. Ag nanoparticle impregnated [AC]F ([AC@Ag]F) characterized by FT-IR, XRD, TGA, DSC and SEM. Instrumental analyses confirmed that Ag nanoparticles significantly impregnated on AC through the functionalization of AC with diethanolamine and it enhances the binding capacity between AC and Ag. The various process parameters, such as contact time, pH, and mass of [AC@Ag]F, were statistically optimized for the recovery of PG using Response Surface Methodology (RSM). The maximum extraction of PG in [AC@Ag]F was found to be 16.2 ± 0.2 mg g-1, its twofold higher than [AC]F. Further, PG conjugated [AC@Ag]F and ([AC@Ag]F-PG) were checked for the growth inhibition of gram negative and gram positive bacteria without formation of biofilm upto 96 h. Hence, the developed matrix could be eco-friendly, viable and lower energy consumption step for separation of the bacterial bioactive PG from fermented broth. In additionally, [AC@Ag]F-PG was used as an antifouling matrix without formation of biofilm.

Performance evaluation of BC-3200 hematology analyzer in a university hospital.

PubMed

Peng, L; Bai, L; Nie, L; Wu, Z; Yan, C

2008-06-01

The BC-3200 automated hematology analyzer was evaluated and compared with the Beckman-Coulter AcT (Ac.T diff 2) 3-part differential hematology analyzer. The BC-3200 was evaluated according to guidelines published by the International Committee for Standardization in Hematology (ICSH), Clinical and Laboratory Standards Institute (CLSI), and Department of Food and Drug Administration (FDA). The results demonstrated no background, minimal carryover (<0.5%), and excellent linearity for hemoglobin (Hb) level, white blood cell (WBC), red blood cell (RBC), and platelet (PLT) counts (>0.998). Precision was generally acceptable for all complete blood count (CBC) parameters; coefficients of variation (CVs) were within the manufacturer's claims and CVs of CBC parameters, including WBC, RBC and PLT counts, Hb and mean corpuscular volume, were <6%. Correlation between the BC-3200 and Ac.T diff 2 was excellent (r > 0.98) for all major CBC parameters (WBC, RBC, and PLT counts and Hb). We conclude that the overall performance of the BC-3200 is excellent and compares well with that of the Coulter Ac.T diff 2.

Retrospective correction of bias in diffusion tensor imaging arising from coil combination mode.

PubMed

Sakaie, Ken; Lowe, Mark

2017-04-01

To quantify and retrospectively correct for systematic differences in diffusion tensor imaging (DTI) measurements due to differences in coil combination mode. Multi-channel coils are now standard among MRI systems. There are several options for combining signal from multiple coils during image reconstruction, including sum-of-squares (SOS) and adaptive combine (AC). This contribution examines the bias between SOS- and AC-derived measures of tissue microstructure and a strategy for limiting that bias. Five healthy subjects were scanned under an institutional review board-approved protocol. Each set of raw image data was reconstructed twice-once with SOS and once with AC. The diffusion tensor was calculated from SOS- and AC-derived data by two algorithms-standard log-linear least squares and an approach that accounts for the impact of coil combination on signal statistics. Systematic differences between SOS and AC in terms of tissue microstructure (axial diffusivity, radial diffusivity, mean diffusivity and fractional anisotropy) were evaluated on a voxel-by-voxel basis. SOS-based tissue microstructure values are systematically lower than AC-based measures throughout the brain in each subject when using the standard tensor calculation method. The difference between SOS and AC can be virtually eliminated by taking into account the signal statistics associated with coil combination. The impact of coil combination mode on diffusion tensor-based measures of tissue microstructure is statistically significant but can be corrected retrospectively. The ability to do so is expected to facilitate pooling of data among imaging protocols. Copyright © 2016 Elsevier Inc. All rights reserved.

Biosynthesis and secretion of catalytically active acetylcholinesterase in Xenopus oocytes microinjected with mRNA from rat brain and from Torpedo electric organ.

PubMed

Soreq, H; Parvari, R; Silman, I

1982-02-01

A novel technique was developed for monitoring the level of the mRNA species that direct the synthesis of acetylcholinesterase (AcChoEase; acetylcholine acetylhydrolase, EC 3.1.1.7), using microinjected Xenopus oocytes as a translation system. When injected with poly(A)-containing RNA from whole rat brain or rat cerebellum and from electric organ of Torpedo ocellata, Xenopus oocytes synthesize and secrete catalytically active cholinesterase. The newly synthesized enzyme, which is mostly secreted into the oocytes incubation medium, appears to be primarily AcChoEase because it is inhibited by the specific inhibitor BW 284C51. The new enzymatic activity can be detected after injection of as little as 12.5 ng of poly(A)-containing RNA per oocyte, and there is a linear dependence of the oocytes' ability to form AcChoEase on the amount of injected RNA. The AcChoEase mRNA displays a tau 1/2 of about 10 +/- 3 hr in injected oocytes. The abundance of AcChoEase mRNA in the total nonfractionated mRNA injected was calculated to be ca. 1 x 10(-5), a value similar to the level of AcChoEase protein determined in rat brain. The combination of the high turnover number of AcChoEase, the efficiency of the oocyte system, and the sensitivity of the assay used thus permit the accurate monitoring of the scarce mRNA species that direct the synthesis of this enzyme.

PERIOD–COLOR AND AMPLITUDE–COLOR RELATIONS AT MAXIMUM AND MINIMUM LIGHT FOR RR LYRAE STARS IN THE SDSS STRIPE 82 REGION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ngeow, Chow-Choong; Kanbur, Shashi M.; Schrecengost, Zachariah

Investigation of period–color (PC) and amplitude–color (AC) relations at the maximum and minimum light can be used to probe the interaction of the hydrogen ionization front (HIF) with the photosphere and the radiation hydrodynamics of the outer envelopes of Cepheids and RR Lyraes. For example, theoretical calculations indicated that such interactions would occur at minimum light for RR Lyrae and result in a flatter PC relation. In the past, the PC and AC relations have been investigated by using either the ( V − R ){sub MACHO} or ( V − I ) colors. In this work, we extend previousmore » work to other bands by analyzing the RR Lyraes in the Sloan Digital Sky Survey Stripe 82 Region. Multi-epoch data are available for RR Lyraes located within the footprint of the Stripe 82 Region in five ( ugriz ) bands. We present the PC and AC relations at maximum and minimum light in four colors: ( u − g ){sub 0}, ( g − r ){sub 0}, ( r − i ){sub 0}, and ( i − z ){sub 0}, after they are corrected for extinction. We found that the PC and AC relations for this sample of RR Lyraes show a complex nature in the form of flat, linear or quadratic relations. Furthermore, the PC relations at minimum light for fundamental mode RR Lyrae stars are separated according to the Oosterhoff type, especially in the ( g − r ){sub 0} and ( r − i ){sub 0} colors. If only considering the results from linear regressions, our results are quantitatively consistent with the theory of HIF-photosphere interaction for both fundamental and first overtone RR Lyraes.« less

Audiometric analyses confirm a cochlear component, disproportional to age, in stapedial otosclerosis.

PubMed

Topsakal, Vedat; Fransen, Erik; Schmerber, Sébastien; Declau, Frank; Yung, Matthew; Gordts, Frans; Van Camp, Guy; Van de Heyning, Paul

2006-09-01

To report the preoperative audiometric profile of surgically confirmed otosclerosis. Retrospective, multicenter study. Four tertiary referral centers. One thousand sixty-four surgically confirmed patients with otosclerosis. Therapeutic ear surgery for hearing improvement. Preoperative audiometric air conduction (AC) and bone conduction (BC) hearing thresholds were obtained retrospectively for 1064 patients with otosclerosis. A cross-sectional multiple linear regression analysis was performed on audiometric data of affected ears. Influences of age and sex were analyzed and age-related typical audiograms were created. Bone conduction thresholds were corrected for Carhart effect and presbyacusis; in addition, we tested to see if separate cochlear otosclerosis component existed. Corrected thresholds were than analyzed separately for progression of cochlear otosclerosis. The study population consisted of 35% men and 65% women (mean age, 44 yr). The mean pure-tone average at 0.5, 1, and 2 kHz was 57 dB hearing level. Multiple linear regression analysis showed significant progression for all measured AC and BC thresholds. The average annual threshold deterioration for AC was 0.45 dB/yr and the annual threshold deterioration for BC was 0.37 dB/yr. The average annual gap expansion was 0.08 dB/year. The corrected BC thresholds for Carhart effect and presbyacusis remained significantly different from zero, but only showed progression at 2 kHz. The preoperative audiological profile of otosclerosis is described. There is a significant sensorineural component in patients with otosclerosis planned for stapedotomy, which is worse than age-related hearing loss by itself. Deterioration rates of AC and BC thresholds have been reported, which can be helpful in clinical practice and might also guide the characterization of allegedly different phenotypes for familial and sporadic otosclerosis.

In-vitro cytotoxicity assessment of carbon-nanodot-conjugated Fe-aminoclay (CD-FeAC) and its bio-imaging applications.

PubMed

Kang, Kyoung Suk; Lee, Hyun Uk; Kim, Moon Il; Park, So Young; Chang, Sung-Jin; Park, Ji-Ho; Huh, Yun Suk; Lee, Jouhahn; Yang, Mino; Lee, Young-Chul; Park, Hyun Gyu

2015-11-26

We have investigated the cytotoxic assay of Fe-aminoclay (FeAC) nanoparticles (NPs) and simultaneous imaging in HeLa cells by photoluminescent carbon nanodots (CD) conjugation. Non-cytotoxic, photostable, and CD NPs are conjugated with cationic FeAC NPs where CD NPs play a role in bio-imaging and FeAC NPs act as a substrate for CD conjugation and help to uptake of NPs into cancer cells due to positively charged surface of FeAC NPs in physiological media. As increase of CD-FeAC NPs loading in HeLa cell in vitro, it showed slight cytotoxicity at 1000 μg/mL but no cytotoxicity for normal cells up to concentration of 1000 μg/mL confirmed by two 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and neutral red (NR) assays, with further observations by 4',6-diamidino-2-phenylindole (DAPI) stained confocal microscopy images, possessing that CD-FeAC NPs can be used as potential drug delivery platforms in cancer cells with simultaneous imaging. Graphical abstract CD conjugation with organo-building blocks of delaminated FeAC NPs.

Reconstitutional Mutagenesis of the Maize P Gene by Short-Range Ac Transpositions

PubMed Central

Moreno, M. A.; Chen, J.; Greenblatt, I.; Dellaporta, S. L.

1992-01-01

The tendency for Ac to transpose over short intervals has been utilized to develop insertional mutagenesis and fine structure genetic mapping strategies in maize. We recovered excisions of Ac from the P gene and insertions into nearby chromosomal sites. These closely linked Ac elements reinserted into the P gene, reconstituting over 250 unstable variegated alleles. Reconstituted alleles condition a variety of variegation patterns that reflect the position and orientation of Ac within the P gene. Molecular mapping and DNA sequence analyses have shown that reinsertion sites are dispersed throughout a 12.3-kb chromosomal region in the promoter, exons and introns of the P gene, but in some regions insertions sites were clustered in a nonrandom fashion. Transposition profiles and target site sequence data obtained from these studies have revealed several features of Ac transposition including its preference for certain target sites. These results clearly demonstrate the tendency of Ac to transpose to nearby sites in both proximal and distal directions from the donor site. With minor modifications, reconstitutional mutagenesis should be applicable to many Ac-induced mutations in maize and in other plant species and can possibly be extended to other eukaryotic transposon systems as well. PMID:1325389

Initial NIST AC QHR Measurements

PubMed Central

Cage, M. E.; Shields, S. H.; Jeffery, A.

2004-01-01

We demonstrate that dc quantized Hall resistance (dc QHR) guideline properties and dc and ac QHR values can be measured without changing sample probe lead connections at the QHR device, and report ac QHR values that converge to the dc QHR value when using four-terminal-pair ac QHR measurements. This was accomplished during one cooldown using single-series and quadruple-series connections outside the sample probe. The QHR was measured from 0 Hz to 5500 Hz in 1:1 ratio at 20 µA to ±1 part in 107 uncertainties with a poor-quality QHR device. A good device would allow an order of magnitude smaller uncertainties over this frequency range. We exchanged positions of the QHR device and reference resistor in the bridge and remeasured the resistance ratios to remove dominant ac bridge effects. PMID:27366620

A Magnesium-Activated Carbon Hybrid Capacitor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoo, HD; Shterenberg, I; Gofer, Y

2013-12-11

Prototype cells of hybrid capacitor were developed, comprising activated carbon (AC) cloth and magnesium (Mg) foil as the positive and negative electrodes, respectively. The electrolyte solution included ether solvent (TBF) and a magnesium organo-halo-aluminate complex 0.25 M Mg2Cl3+-Ph2AlCl2-. In this solution Mg can be deposited/dissolved reversibly for thousands of cycles with high reversibility (100% cycling efficiency). The main barrier for integrating porous AC electrodes with this electrolyte solution was the saturation of the pores with the large ions in the AC prior to reaching the potential limit. This is due to the existence of bulky Mg and Al based ionicmore » complexes consisting Cl, alkyl or aryl (R), and THF ligands. This problem was resolved by adding 0.5 M of lithium chloride (LiCl), thus introducing smaller ionic species to the solution. This Mg hybrid capacitor system demonstrated a stable cycle performance for many thousands of cycles with a specific capacitance of 90 Fg(-1) for the AC positive electrodes along a potential range of 2.4 V. (C) 2014 The Electrochemical Society. All rights reserved.« less

Microbial Contamination of Ice Machines Is Mediated by Activated Charcoal Filtration Systems in a City Hospital.

PubMed

Yorioka, Katsuhiro; Oie, Shigeharu; Hayashi, Koji; Kimoto, Hiroo; Furukawa, Hiroyuki

2016-06-01

Although microbial contamination of ice machines has been reported, no previous study has addressed microbial contamination of ice produced by machines equipped with activated charcoal (AC) filters in hospitals. The aim of this study was to provide clinical data for evaluating AC filters to prevent microbial contamination of ice. We compared microbial contamination in ice samples produced by machines with (n = 20) and without an AC filter (n = 40) in Shunan City Shinnanyo Municipal Hospital. All samples from the ice machine equipped with an AC filter contained 10-116 CFUs/g of glucose nonfermenting gram-negative bacteria such as Pseudomonas aeruginosa and Chryseobacterium meningosepticum. No microorganisms were detected in samples from ice machines without AC filters. After the AC filter was removed from the ice machine that tested positive for Gram-negative bacteria, the ice was resampled (n = 20). Analysis found no contaminants. Ice machines equipped with AC filters pose a serious risk factor for ice contamination. New filter-use guidelines and regulations on bacterial detection limits to prevent contamination of ice in healthcare facilities are necessary.

High surface area bio-waste based carbon as a superior electrode for vanadium redox flow battery

NASA Astrophysics Data System (ADS)

Maharjan, Makhan; Bhattarai, Arjun; Ulaganathan, Mani; Wai, Nyunt; Oo, Moe Ohnmar; Wang, Jing-Yuan; Lim, Tuti Mariana

2017-09-01

Activated carbon (AC) with high surface area (1901 m2 g-1) is synthesized from low cost bio-waste orange (Citrus sinensis) peel for vanadium redox flow battery (VRB). The composition, structure and electrochemical properties of orange peel derived AC (OP-AC) are characterized by elemental analyzer, field emission-scanning electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy. CV results show that OP-AC coated bipolar plate demonstrates improved electro-catalytic activity in both positive and negative side redox couples than the pristine bipolar plate electrode and this is ascribed to the high surface area of OP-AC which provides effective electrode area and better contact between the porous electrode and bipolar plate. Consequently, the performance of VRB in a static cell shows higher energy efficiency for OP-AC electrode than the pristine electrode at all current densities tested. The results suggest the OP-AC to be a promising electrode for VRB applications and can be incorporated into making conducting plastics electrode to lower the VRB cell stack weight and cost.

Serum IL-18 level, clinical symptoms and IL-18-607A/C polymorphism among chronic patients with schizophrenia in a Chinese Han population.

PubMed

Zhang, Xiang Yang; Tan, Yun-Long; Chen, Da-Chun; Tan, Shu-Ping; Malouta, Michelle Z; Bernard, Jared D; Combs, Jessica L; Bhatti, Sarai; Davis, Michael C; Kosten, Thomas R; Soares, Jair C

2016-06-01

Literature suggests that alterations in the inflammatory and immune systems are involved in the pathogenesis of schizophrenia. Specifically, patients diagnosed with schizophrenia exhibit increased IL-18, a pleiotropic proinflammatory cytokine in type 1 T-helper (Th1) responses. The functional 607A/C promoter polymorphism of the IL-18 gene is also associated with the psychopathology of this disorder. However, no current study has explored its role in the clinical symptoms of schizophrenia as mediated through IL-18 levels. We recruited 772 inpatients with schizophrenia and 775 healthy controls in a Han Chinese population and genotyped the IL-18-607A/C polymorphism. Patient psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS). Serum IL-18 levels were measured in 80 patients and 93 healthy controls. Our results showed that there were no significant differences in the distribution of the allele and genotype frequencies between the patients and controls. Both increased IL-18 serum level and the IL-18-607A/C polymorphism were positively associated with the PANSS general psychopathology subscore and the PANSS total score. Moreover, interaction of increased IL-18 serum level and the IL-18-607A/C polymorphism influenced the clinical psychopathological symptoms, indicating that association of IL-18 level with the PANSS general psychopathology subscale or the total scores was present only among patients carrying the C allele. We demonstrate an association between the IL-18-607A/C variant and clinical psychopathological symptoms in schizophrenia. Findings suggest that the association between higher IL-18 levels and clinical symptoms in schizophrenia is dependent on the IL-18-607A/C polymorphism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Non-target screening of Allura Red AC photodegradation products in a beverage through ultra high performance liquid chromatography coupled with hybrid triple quadrupole/linear ion trap mass spectrometry.

PubMed

Gosetti, Fabio; Chiuminatto, Ugo; Mazzucco, Eleonora; Calabrese, Giorgio; Gennaro, Maria Carla; Marengo, Emilio

2013-01-15

The study deals with the identification of the degradation products formed by simulated sunlight photoirradiation in a commercial beverage that contains Allura Red AC dye. An UHPLC-MS/MS method, that makes use of hybrid triple quadrupole/linear ion trap, was developed. In the identification step the software tool information dependent acquisition (IDA) was used to automatically obtain information about the species present and to build a multiple reaction monitoring (MRM) method with the MS/MS fragmentation pattern of the species considered. The results indicate that the identified degradation products are formed from side-reactions and/or interactions among the dye and other ingredients present in the beverage (ascorbic acid, citric acid, sucrose, aromas, strawberry juice, and extract of chamomile flowers). The presence of aromatic amine or amide functionalities in the chemical structures proposed for the degradation products might suggest potential hazards to consumer health. Copyright © 2012 Elsevier Ltd. All rights reserved.

Advanced complex trait analysis.

PubMed

Gray, A; Stewart, I; Tenesa, A

2012-12-01

The Genome-wide Complex Trait Analysis (GCTA) software package can quantify the contribution of genetic variation to phenotypic variation for complex traits. However, as those datasets of interest continue to increase in size, GCTA becomes increasingly computationally prohibitive. We present an adapted version, Advanced Complex Trait Analysis (ACTA), demonstrating dramatically improved performance. We restructure the genetic relationship matrix (GRM) estimation phase of the code and introduce the highly optimized parallel Basic Linear Algebra Subprograms (BLAS) library combined with manual parallelization and optimization. We introduce the Linear Algebra PACKage (LAPACK) library into the restricted maximum likelihood (REML) analysis stage. For a test case with 8999 individuals and 279,435 single nucleotide polymorphisms (SNPs), we reduce the total runtime, using a compute node with two multi-core Intel Nehalem CPUs, from ∼17 h to ∼11 min. The source code is fully available under the GNU Public License, along with Linux binaries. For more information see http://www.epcc.ed.ac.uk/software-products/acta. a.gray@ed.ac.uk Supplementary data are available at Bioinformatics online.

Fate and distribution of pharmaceutically active compounds in mesocosm constructed wetlands.

PubMed

He, Yujie; Sutton, Nora B; Lei, Yu; Rijnaarts, Huub H M; Langenhoff, Alette A M

2018-05-22

Removal of pharmaceutically active compounds (PhACs) in constructed wetlands (CWs) is a complex interplay of different processes. We studied fate and distribution of seven PhACs (caffeine, CAF; naproxen, NAP; metoprolol, MET; propranolol, PRO; ibuprofen, IBP; carbamazepine, CBZ; diclofenac, DFC) in mesocosm CWs and effects of irradiation via pre-photocatalysis, substrate composition (mainly sediment) through addition of litter (dead plant biomass), and plants. CWs showed high removal of CAF, NAP, MET, PRO, and IBP (79-99%). All seven PhACs were detected in substrate and plant tissues as well as IBP intermediates. Estimated PhAC mass balance showed that sorption dominated PRO removal in CWs while other PhACs were mainly removed by biodegradation and/or phytodegradation. Pre-photocatalysis significantly increased removal of PhACs except for CAF and IBP, and decreased accumulation of PhACs in substrate and plant tissues of the following wetland compartment. Litter addition in CW significantly enhanced removal of PRO and CBZ via biodegradation and/or phytodegradation. Plants played an essential and positive role in removing PhACs, resulting from direct phytoremediation and indirectly enhancing sorption and biodegradation. Our study provides knowledge to understand removal mechanisms of PhACs in CWs and to potentially enhance PhAC removal by developing pre-photocatalysis, adding dead plant biomass, and optimizing vegetation. Copyright © 2018 Elsevier B.V. All rights reserved.

Investigation of the transition of multicycle AC operation in ISTTOK under edge electrode biasing

NASA Astrophysics Data System (ADS)

Malaquias, A.; Henriques, R. B.; Silva, C.; Figueiredo, H.; Nedzelskiy, I. S.; Fernandes, H.; Sharma, R.; Plyusnin, V. V.

2017-11-01

In this paper we present recent results obtained on plasma edge electrode biasing during AC discharges. The goal is to obtain experimental evidence on a number of plasma parameters that can play a role during the AC transition on the repeatability and reproducibility of AC operation. The control of the plasma density in the quiescent phase is made just before the AC transition by means of positive edge biasing leading to a transitory improved of density (30%-40%). Gas puff experiments show that the increase of background gas pressure during discharge led to a better success of the AC transition. The experimental results indicate that the increase of density during the AC transition induced by edge biasing is followed by an electron temperature drop. The drop in electron temperature leads in most cases the formation of runaway electrons. It has been observed that the runaway population during discharge flattop depends on the interplay between gas content and plasma density and temperature. The results also confirm that the correct balance of external magnetic fields is crucial during the AC transition phase where drift electron currents are formed. The results from the heavy ion beam diagnostic show that the formation of plasma current during consecutive AC transitions is asymmetric. Numerical simulations indicate that for some particular conditions this result could be reproduced from assuming the presence of two counter-currents during AC transition.

Evaluation of constant current alternating current iontophoresis for transdermal drug delivery.

PubMed

Yan, Guang; Li, S Kevin; Higuchi, William I

2005-12-10

Previous studies in our laboratory have demonstrated that alternating current (AC) iontophoresis can significantly decrease skin electric resistance and enhance the transport of charged permeants across skin. Flux variability of neutral permeants during AC iontophoresis was also found to be less than that of conventional direct current (DC) iontophoresis. The objectives of the present study were to evaluate flux enhancement of constant current AC transdermal iontophoresis and compare the AC flux with that of constant current DC iontophoresis. Iontophoresis studies of AC amplitude of 1, 2, and 5 mA were conducted in side-by-side diffusion cells with donor solution of 0.015, 0.15, and 1.0 M tetraethylammonium (TEA) chloride and receiver solution of phosphate buffered saline (PBS) using human epidermal membrane (HEM). Conventional constant current DC iontophoresis of 0.2 mA was also performed under similar conditions. TEA and mannitol were the model permeants. The following are the major findings in the present study. The flux of TEA increased proportionally with the AC current for all three TEA chloride concentrations and at the AC frequency used in the present study. When the permeant and its counter ion were the only ionic species in the donor chamber, the fluxes during DC iontophoresis were weakly dependent of its donor concentration. The fluxes of TEA during constant current AC iontophoresis were moderately related to the donor concentration with the highest TEA flux observed under the 1.0 M TEA chloride condition although the relationship between flux and donor concentration was not linear. A trend of decreasing electroosmotic transport with increasing donor TEA chloride concentration was observed with significant sample-to-sample variability during DC iontophoresis. Mannitol permeability was also observed to decrease with increasing TEA chloride concentration in the donor under the AC conditions, but data variability under AC was significantly smaller than that under DC. The results in the present study indicate that constant current AC iontophoresis under conditions tolerable to human (2 and 5 mA) can provide predictable fluxes that were lower than but of comparable magnitude as those of conventional constant current DC iontophoresis (0.2 mA).

A new bed-exiting alarm system for welfare facility residents.

PubMed

Ogawa, Hidekuni; Yonezawa, Yoshiharu; Maki, Hiromichi; Caldwell, W

2009-01-01

A newly developed alarm system detects welfare facility residents leaving their beds, and does not respond to the care staff, who wear shoes or slippers. It employs a stainless steel tape electrode, several linear integrated circuits and a low-power 8-bit single chip microcomputer. The electrode, which is used as a bed-exiting detection sensor, is attached to the floor mat to record changes in the always-present AC (alternating current) voltage induced on the patient's body by electrostatic coupling from the standard 100 volt, 60 Hz AC utility power wiring in the room walls and ceiling. The resident's body movements, before trying to get out of bed and after leaving the bed, are detected by the microcomputer from changes in the induced AC voltage. The microcomputer alerts the care staff station, via a power line communication system or PHS (personal handy phone System).

Amination of activated carbon for enhancing phenol adsorption: Effect of nitrogen-containing functional groups

NASA Astrophysics Data System (ADS)

Yang, Guo; Chen, Honglin; Qin, Hangdao; Feng, Yujun

2014-02-01

To study the contribution of different nitrogen-containing functional groups to enhancement of phenol adsorption, the aminated activated carbons (AC) were characterized by N2 adsorption/desorption, XPS, Boehm titration, and pH drift method and tested for adsorption behaviors of phenol. Adsorption isotherm fitting revealed that the Langmuir model was preferred for the aminated ACs. The adsorption capacity per unit surface area (qm/SSABET) was linearly correlated with the amount of pyridinic and pyrrolic N, which suggested that these two functional groups played a critical role in phenol adsorption. The enhancement of adsorption capacity was attributed to the strengthened π-π dispersion between phenol and basal plane of AC by pyridinic, pyrrolic N. The adsorption kinetics was found to follow the pseudo-second-order kinetic model, and intraparticle diffusion was one of the rate-controlling steps in the adsorption process.

Dynamic ADMM for Real-Time Optimal Power Flow

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall-Anese, Emiliano; Zhang, Yijian; Hong, Mingyi

This paper considers distribution networks featuring distributed energy resources (DERs), and develops a dynamic optimization method to maximize given operational objectives in real time while adhering to relevant network constraints. The design of the dynamic algorithm is based on suitable linearization of the AC power flow equations, and it leverages the so-called alternating direction method of multipliers (ADMM). The steps of the ADMM, however, are suitably modified to accommodate appropriate measurements from the distribution network and the DERs. With the aid of these measurements, the resultant algorithm can enforce given operational constraints in spite of inaccuracies in the representation ofmore » the AC power flows, and it avoids ubiquitous metering to gather the state of noncontrollable resources. Optimality and convergence of the proposed algorithm are established in terms of tracking of the solution of a convex surrogate of the AC optimal power flow problem.« less

Dynamic ADMM for Real-Time Optimal Power Flow: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall-Anese, Emiliano; Zhang, Yijian; Hong, Mingyi

This paper considers distribution networks featuring distributed energy resources (DERs), and develops a dynamic optimization method to maximize given operational objectives in real time while adhering to relevant network constraints. The design of the dynamic algorithm is based on suitable linearizations of the AC power flow equations, and it leverages the so-called alternating direction method of multipliers (ADMM). The steps of the ADMM, however, are suitably modified to accommodate appropriate measurements from the distribution network and the DERs. With the aid of these measurements, the resultant algorithm can enforce given operational constraints in spite of inaccuracies in the representation ofmore » the AC power flows, and it avoids ubiquitous metering to gather the state of non-controllable resources. Optimality and convergence of the propose algorithm are established in terms of tracking of the solution of a convex surrogate of the AC optimal power flow problem.« less

Dating archeological ceramics from the Valley of Vitor, Arequipa by the TL method

NASA Astrophysics Data System (ADS)

Cano, N. F.; Arizaca, E. C.; Yauri, J. M.; Arenas, J. S. A.; Watanabe, S.

The age of some ancient pottery from the Valley of Vitor in the region of Arequipa, Peru, is determined by the thermoluminescence (TL) method. For dating, a 325 °C TL peak was used and irradiation with γ-dose from 5 to 50 Gy was carried out for the additive method, and from 0.4 to 5 Gy for the regeneration method. For these dose values, the TL intensity is observed to grow linearly, obtaining an accumulated dose of 1.62±0.09 Gy and 1.36±0.03 Gy for the additive and regeneration methods, respectively. The age (A) of the sample was calculated by the two methods, being A=867±195 years after Christ (AC) for the additive method and A=1050±157 years AC for the regeneration method. Both results are within 800-1200 years AC, which is the period of the Wari culture.

Dielectrophoresis of gold nanoparticles conjugated to DNA origami structures

PubMed Central

Wiens, Matthew; Lakatos, Mathias; Heerwig, Andreas; Ostermaier, Frieder; Haufe, Nora

2016-01-01

Summary DNA nanostructures are promising construction materials to bridge the gap between self-assembly of functional molecules and conventional top-down fabrication methods in nanotechnology. Their positioning onto specific locations of a microstructured substrate is an important task towards this aim. Here we study manipulation and positioning of pristine and of gold nanoparticle-conjugated tubular DNA origami structures using ac dielectrophoresis. The dielectrophoretic behavior was investigated employing fluorescence microscopy. For the pristine origami, a significant dielectrophoretic response was found to take place in the megahertz range, whereas, due to the higher polarizability of the metallic nanoparticles, the nanoparticle/DNA hybrid structures required a lower electrical field strength and frequency for a comparable trapping at the edges of the electrode structure. The nanoparticle conjugation additionally resulted in a remarkable alteration of the DNA structure arrangement. The growth of linear, chain-like structures in between electrodes at applied frequencies in the megahertz range was observed. The long-range chain formation is caused by a local, gold nanoparticle-induced field concentration along the DNA nanostructures, which in turn, creates dielectrophoretic forces that enable the observed self-alignment of the hybrid structures. PMID:27547612

New functional materials AC3B4O12 (Review)

NASA Astrophysics Data System (ADS)

Vasil'ev, A. N.; Volkova, O. S.

2007-11-01

The physical properties of perovskites of the type AC3B4O12, whose structure derives from simple perovskites ABO3, are reviewed. The A position is subject to strong structural distortions and splits into two new positions A and C. In the structure of AC3B4O12 vacancies and any cations with a large radius, irrespective of their charge state, can be present in the icosahedral environment of A: Na +, Cd2+, Ca2+, Sr2+, Y3+, Ln3+, and Nd4+. The C position in the square environment of oxygen can be occupied only by the Jahn-Teller cations Cu2+ and Mn3+. Transition and nontransition metal ions—Mn3+, Fe3+, Al3+, Cr3+, Ti4+, Mn4+, Ge4+, Ru4+, Ir4+, Ta5+, Nb5+, Ta5+, Sb5+—can occupy the B position in an octahedral environment. Some members of the family of complex perovskites possess properties which are characteristic for systems with heavy fermions; collinear and noncollinear magnetic structures with high ordering temperatures occur in these materials; tunneling magnetoresistance and high permittivity are observed. The diversity and unique properties make these materials attractive for practical applications.

Sensitivity of hepatobiliary imaging and real-time ultrasonography in the detection of acute cholecystitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fink-Bennett, D.; Freitas, J.E.; Ripley, S.D.

To determine the sensitivity of hepatobiliary imaging (HBI) and strict- and liberal-criteria real-time ultrasonography (RTUS), the authors retrospectively analyzed 100 cases of pathologically proved acute cholecystitis (AC). A positive HBI was one in which there was nonvisualization of the gallbladder up to four hours after the administration of technetium 99m-disofenin. In the absence of hypoalbuminemia, cirrhosis, or ascites, pathognomonic RTUS findings (strict criteria) for AC were wall edema and/or pericholecystic fluid. Findings indicative of AC (liberal criteria) included the demonstration of stones, a thick gallbladder wall, nonshadowing echoes, or the ultrasonographic Murphy's sign. Of the 100 cases of AC, 91more » were calculous, and nine were acalculous. Four of 100 patients had associated choledocholithiasis. The sensitivities in detecting calculous AC were as follows: HBI, 97%; liberal-criteria RTUS, 86%; and strict-criteria RTUS, 24%. The sensitivities in detecting acalculous AC were as follows: HBI, 100%; liberal-criteria RTUS, 89%; and strict-criteria RTUS, 44%.« less

Closed Loop Software Control of the MIDEX Power System

NASA Technical Reports Server (NTRS)

Castell, Karen; Hernandez-Pellerano, Amri; Wismer, Margaret

1998-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE) spacecraft. The design and analysis of the MAP attitude control system (ACS) have been refined since work previously reported. The full spacecraft and instrument flexible model was developed in NASTRAN, and the resulting flexible modes were plotted and reduced with the Modal Significance Analysis Package (MSAP). The reduced-order model was used to perform the linear stability analysis for each control mode, the results of which are presented in this paper. Although MAP is going to a relatively disturbance-free Lissajous orbit around the Earth-Sun L2 Lagrange point, a detailed disturbance-torque analysis is required because there are only a small number of opportunities for momentum unloading each year. Environmental torques, including solar pressure at L2, and aerodynamic and gravity gradient during phasing-loop orbits, were calculated and simulated. A simple model of fuel slosh was derived to model its effect on the motion of the spacecraft. In addition, a thruster mode linear impulse controller was developed to meet the accuracy requirements of the phasing loop burns. A dynamic attitude error limiter was added to improve the performance of the ACS during large attitude slews. The result of this analysis is a stable ACS subsystem that meets all of the mission's requirements.

Short-term metal particulate exposures decrease cardiac acceleration and deceleration capacities in welders: a repeated-measures panel study.

PubMed

Umukoro, Peter E; Cavallari, Jennifer M; Fang, Shona C; Lu, Chensheng; Lin, Xihong; Mittleman, Murray A; Christiani, David C

2016-02-01

Acceleration (AC) and deceleration (DC) capacities measure heart rate variability during speeding up and slowing down of the heart, respectively. We investigated associations between AC and DC with occupational short-term metal PM2.5 exposures. A panel of 48 male welders had particulate matter less than 2.5 microns in diameter (PM2.5) exposure measurements over 4-6 h repeated over 5 sampling periods between January 2010 and June 2012. We simultaneously obtained continuous recordings of digital ECG using a Holter monitor. We analysed ECG data in the time domain to obtain hourly AC and DC. Linear mixed models were used to assess the associations between hourly PM2.5 exposure and each of hourly AC and DC, controlling for age, smoking status, active smoking, exposure to secondhand smoke, season/time of day when ECG reading was obtained and baseline AC or DC. We also ran lagged exposure response models for each successive hour up to 3 h after onset of exposure. Mean (SD) shift PM2.5 exposure during welding was 0.47 (0.43) mg/m(3). Significant exposure-response associations were found for AC and DC with increased PM2.5 exposure. In our adjusted models without any lag between exposure and response, a 1 mg/m(3) increase of PM2.5 was associated with a decrease of 1.46 (95% CI 1.00 to 1.92) ms in AC and a decrease of 1.00 (95% CI 0.53 to 1.46) ms in DC. The effect of PM2.5 on AC and DC was maximal immediately postexposure and lasted 1 h following exposure. There are short-term effects of metal particulates on AC and DC. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Adding source positions to the IVS Combination

NASA Astrophysics Data System (ADS)

Bachmann, S.; Thaller, D.

2016-12-01

Simultaneous estimation of source positions, Earth orientation parameters (EOPs) and station positions in one common adjustment is crucial for a consistent generation of celestial and terrestrial reference frame (CRF and TRF, respectively). VLBI is the only technique to guarantee this consistency. Previous publications showed that the VLBI intra-technique combination could improve the quality of the EOPs and station coordinates compared to the individual contributions. By now, the combination of EOP and station coordinates is well established within the IVS and in combination with other space geodetic techniques (e.g. inter-technique combined TRF like the ITRF). Most of the contributing IVS Analysis Centers (AC) now provide source positions as a third parameter type (besides EOP and station coordinates), which have not been used for an operational combined solution yet. A strategy for the combination of source positions has been developed and integrated into the routine IVS combination. Investigations are carried out to compare the source positions derived from different IVS ACs with the combined estimates to verify whether the source positions are improved by the combination, as it has been proven for EOP and station coordinates. Furthermore, global solutions of source positions, i.e., so-called catalogues describing a CRF, are generated consistently with the TRF similar to the IVS operational combined quarterly solution. The combined solutions of the source positions time series and the consistently generated TRF and CRF are compared internally to the individual solutions of the ACs as well as to external CRF catalogues and TRFs. Additionally, comparisons of EOPs based on different CRF solutions are presented as an outlook for consistent EOP, CRF and TRF realizations.

Large amplitude Fourier transformed ac voltammetry at a rotating disc electrode: a versatile technique for covering Levich and flow rate insensitive regimes in a single experiment.

PubMed

Bano, Kiran; Kennedy, Gareth F; Zhang, Jie; Bond, Alan M

2012-04-14

The theory for large amplitude Fourier transformed ac voltammetry at a rotating disc electrode is described. Resolution of time domain data into dc and ac harmonic components reveals that the mass transport for the dc component is controlled by convective-diffusion, while the background free higher order harmonic components are flow rate insensitive and mainly governed by linear diffusion. Thus, remarkable versatility is available; Levich behaviour of the dc component limiting current provides diffusion coefficient values and access to higher harmonics allows fast electrode kinetics to be probed. Two series of experiments (dc and ac voltammetry) have been required to extract these parameters; here large amplitude ac voltammetry with RDE methodology is used to demonstrate that kinetics and diffusion coefficient information can be extracted from a single experiment. To demonstrate the power of this approach, theoretical and experimental comparisons of data obtained for the reversible [Ru(NH(3))(6)](3+/2+) and quasi-reversible [Fe(CN)(6)](3-/4-) electron transfer processes are presented over a wide range of electrode rotation rates and with different concentrations and electrode materials. Excellent agreement of experimental and simulated data is achieved, which allows parameters such as electron transfer rate, diffusion coefficient, uncompensated resistance and others to be determined using a strategically applied approach that takes into account the different levels of sensitivity of each parameter to the dc or the ac harmonic.

The therapeutic potential of polymersomes loaded with 225Ac evaluated in 2D and 3D in vitro glioma models.

PubMed

de Kruijff, R M; van der Meer, A J G M; Windmeijer, C A A; Kouwenberg, J J M; Morgenstern, A; Bruchertseifer, F; Sminia, P; Denkova, A G

2018-06-01

Alpha emitters have great potential in targeted tumour therapy, especially in destroying micrometastases, due to their high linear energy transfer (LET). To prevent toxicity caused by recoiled daughter atoms in healthy tissue, alpha emitters like 225 Ac can be encapsulated in polymeric nanocarriers (polymersomes), which are capable of retaining the daughter atoms to a large degree. In the translation to a (pre-)clinical setting, it is essential to evaluate their therapeutic potential. As multicellular tumour spheroids mimic a tumour microenvironment more closely than a two-dimensional cellular monolayer, this study has focussed on the interaction of the polymersomes with U87 human glioma spheroids. We have found that polymersomes distribute themselves throughout the spheroid after 4 days which, considering the long half-life of 225 Ac (9.9 d) (Vaidyanathan and Zalutsky, 1996), allows for irradiation of the entire spheroid. A decrease in spheroidal growth has been observed upon the addition of only 0.1 kBq 225 Ac, an effect which was more pronounced for the 225 Ac in polymersomes than when only coupled to DTPA. At higher activities (5 kBq), the spheroids have been found to be destroyed completely after two days. We have thus demonstrated that 225 Ac containing polymersomes effectively inhibit tumour spheroid growth, making them very promising candidates for future in vivo testing. Copyright © 2018 Elsevier B.V. All rights reserved.

First observation of N-acetyl leucine and N-acetyl isoleucine in diabetic patient hair and quantitative analysis by UPLC-ESI-MS/MS.

PubMed

Min, Jun Zhe; Tomiyasu, Yuki; Morotomi, Takashi; Jiang, Ying-Zi; Li, Gao; Shi, Qing; Yu, Hai-Fu; Inoue, Koichi; Todoroki, Kenichiro; Toyo'oka, Toshimasa

2015-04-15

Type 2 diabetes patients (DP) have significantly higher plasma levels of valine, leucine, isoleucine and alanine than the controls. Specific amino acids may acutely and chronically regulate insulin secretion from the pancreatic β-cells. We recently identified a metabolic signature of N-acetyl leucine (Ac-Leu) that strongly predicts diabetes development in mice hair. The Ac-Leu appears to be a potential biomarker candidate related to diabetes. However, the determination of Ac-Leu in human hair has not been reported. We measured the Ac-Leu, and its structure is similar to N-acetyl isoleucine (Ac-Ile) in human hair by ultra-performance liquid chromatography (UPLC) with electrospray ionization tandem mass spectrometry (ESI-MS/MS). The developed method was applied to the determination of Ac-Leu and Ac-Ile in the hair of healthy volunteers (HV) and DP. Ac-Leu, Ac-Ile and N-acetyl norleucine (Ac-Nle, IS) were extracted from human hair samples by a micropulverized extraction procedure, then separated on a C18 column by isocratic elution of acetonitrile-0.1% formic acid in water:0.1% formic acid (14:86, vol./vol.). MRM using the fragmentation transitions of m/z 174.1→86.1 in the positive ESI mode was performed to quantify the N-acetyl leucine, N-acetyl isoleucine and IS. Ac-Leu, Ac-Ile and Ac-Nle in the human hair samples were completely separated by isocratic elution of a 5.0 min duration wash program using a reversed-phase column, and sensitively detected by LC-MS/MS in the ESI(+) MRM mode. The amounts of Ac-Leu and Ac-Ile in the hairs of HV and DP were determined. When comparing the concentrations between DP and those from HV, a statistically significant correlation was observed for the Ac-Leu (p<0.001) and Ac-Ile (p<0.01). The proposed method is useful for the determination of Ac-Leu and Ac-Ile in the hairs of DP and HV. Human hair may serve as a noninvasive biosample for the diagnosis of diabetes. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Antiferromagnetic spin current rectifier

NASA Astrophysics Data System (ADS)

Khymyn, Roman; Tiberkevich, Vasil; Slavin, Andrei

2017-05-01

It is shown theoretically, that an antiferromagnetic dielectric with bi-axial anisotropy, such as NiO, can be used for the rectification of linearly-polarized AC spin current. The AC spin current excites two evanescent modes in the antiferromagnet, which, in turn, create DC spin current flowing back through the antiferromagnetic surface. Spin diode based on this effect can be used in future spintronic devices as direct detector of spin current in the millimeter- and submillimeter-wave bands. The sensitivity of such a spin diode is comparable to the sensitivity of modern electric Schottky diodes and lies in the range 102-103 V/W for 30 ×30 nm2 structure.

A Field Investigation of the Effects of Drinking Consequences on Young Adults’ Readiness to Change

PubMed Central

Usala, Julie M.; Celio, Mark A.; Lisman, Stephen A.; Day, Anne M.; Spear, Linda P.

2014-01-01

In the research on readiness to change (RTC) one’s drinking, there has been little assessment of the influence of positive drinking consequences or other potential moderating variables. To address these limitations, we examined how young adults’ RTC their alcohol consumption shortly following a drinking episode was associated with self-reported drinking consequences, as well as any potential moderating effects of gender and Breath Alcohol Concentration (BrAC). In street interviews outside bars, 238 young adults were administered questionnaires about their drinking, including a measure examining participants’ current readiness to reduce their alcohol consumption. Within 72 hours of their drinking episode, 67 participants (36 males; Entire Sample Mage = 20.90 years, Range = 18–26 years) completed an online survey, once again measuring RTC as well as positive and negative drinking consequences. Consistent with our hypothesis, positive drinking consequences were negatively associated with participants’ changes in RTC. Additionally, a three-way interaction of gender x BrAC x Positive Drinking Consequences on RTC showed that females with low BrACs reported higher RTC scores when they had endorsed fewer positive drinking consequences. Interestingly, negative drinking consequences alone did not impact individuals’ RTC. Because positive drinking consequences were a significantly better predictor of RTC than were negative drinking consequences, researchers are advised to examine both types of consequences in future studies. Finally, effective alcohol education programs for those who have never consumed alcohol as well as social drinkers should include consideration of the experience of positive outcomes. PMID:25452061

Transduction of cultured fish cells with recombinant baculoviruses.

PubMed

Leisy, Douglas J; Lewis, Teresa D; Leong, Jo-Ann C; Rohrmann, George F

2003-05-01

Five fish cell lines were tested for their ability to be transduced by Ac-CAlacZ, a recombinant baculovirus that is capable of expressing a beta-galactosidase reporter gene from the CAG promoter (consisting of a cytomegalovirus enhancer element, a chicken actin promoter and rabbit beta-globin termination sequences). TO (Tilapia ovary), EPC (carp), CHH-1 (Chum salmon heart fibroblast) and CHSE-214 (chinook salmon embryo) cells were transducible, as demonstrated by an in situ beta-galactosidase assay, whereas RTG-2 (rainbow trout gonad) cells were not. The EPC cell line was used for more detailed studies on baculovirus transduction. The transduction frequency was found to be higher at 28 degrees C than at 21 degrees C. Addition of the histone deacetylase inhibitor sodium butyrate increased the number of blue cells detected 5- to 7-fold. The m.o.i. was positively correlated with transduction frequency, although the relationship did not appear to be strictly linear, as has been observed with mammalian cells. The temperature at which baculoviruses were adsorbed to EPC cells did not affect levels of beta-galactosidase expression. We also examined expression levels of beta-galactosidase in EPC cells after infection with a baculovirus construct that overexpresses the vesicular stomatitis virus G protein and displays it on the virion surface. Expression levels with this virus were approximately 15-fold higher than were observed with Ac-CAlacZ.

Spin noise spectroscopy beyond thermal equilibrium and linear response.

PubMed

Glasenapp, P; Sinitsyn, N A; Yang, Luyi; Rickel, D G; Roy, D; Greilich, A; Bayer, M; Crooker, S A

2014-10-10

Per the fluctuation-dissipation theorem, the information obtained from spin fluctuation studies in thermal equilibrium is necessarily constrained by the system's linear response functions. However, by including weak radio frequency magnetic fields, we demonstrate that intrinsic and random spin fluctuations even in strictly unpolarized ensembles can reveal underlying patterns of correlation and coupling beyond linear response, and can be used to study nonequilibrium and even multiphoton coherent spin phenomena. We demonstrate this capability in a classical vapor of (41)K alkali atoms, where spin fluctuations alone directly reveal Rabi splittings, the formation of Mollow triplets and Autler-Townes doublets, ac Zeeman shifts, and even nonlinear multiphoton coherences.

Optical laboratory solution and error model simulation of a linear time-varying finite element equation

NASA Technical Reports Server (NTRS)

Taylor, B. K.; Casasent, D. P.

1989-01-01

The use of simplified error models to accurately simulate and evaluate the performance of an optical linear-algebra processor is described. The optical architecture used to perform banded matrix-vector products is reviewed, along with a linear dynamic finite-element case study. The laboratory hardware and ac-modulation technique used are presented. The individual processor error-source models and their simulator implementation are detailed. Several significant simplifications are introduced to ease the computational requirements and complexity of the simulations. The error models are verified with a laboratory implementation of the processor, and are used to evaluate its potential performance.

An AC modulated near infrared gain calibration system for a "Violin-Mode" transimpedance amplifier, intended for advanced LIGO suspensions.

PubMed

Lockerbie, N A; Tokmakov, K V

2016-07-01

The background to this work was a prototype shadow sensor, which was designed for retro-fitting to an advanced LIGO (Laser Interferometer Gravitational wave Observatory) test-mass/mirror suspension, in which a 40 kg test-mass/mirror is suspended by four approximately 600 mm long by 0.4 mm diameter fused-silica suspension fibres. The shadow sensor comprised a LED source of Near InfraRed (NIR) radiation, and a "tall-thin" rectangular silicon photodiode detector, which together were to bracket the fibre under test. The photodiode was positioned so as to be sensitive (primarily) to transverse "Violin-Mode" vibrations of such a fibre, via the oscillatory movement of the shadow cast by the fibre, as this moved across the face of the detector. In this prototype shadow sensing system the photodiode was interfaced to a purpose-built transimpedance amplifier, this having both AC and DC outputs. A quasi-static calibration was made of the sensor's DC responsivity, i.e., incremental rate of change of output voltage versus fibre position, by slowly scanning a fused-silica fibre sample transversely through the illuminating beam. The work reported here concerns the determination of the sensor's more important AC (Violin-Mode) responsivity. Recognition of the correspondence between direct AC modulation of the source, and actual Violin-Mode signals, and of the transformative role of the AC/DC gain ratio for the amplifier, at any modulation frequency, f, resulted in the construction of the AC/DC calibration source described here. A method for determining in practice the transimpedance AC/DC gain ratio of the photodiode and amplifier, using this source, is illustrated by a specific numerical example, and the gain ratio for the prototype sensing system is reported over the frequency range 1 Hz-300 kHz. In fact, a maximum DC responsivity of 1.26 kV.m(-1) was measured using the prototype photodiode sensor and amplifier discussed here. Therefore, the measured AC/DC transimpedance gain ratio of 922.5 for this sensor, at 500 Hz, translated into a maximum Violin-Mode (AC) responsivity of (1.16 ± 0.05) MV m(-1), at that frequency.

Photovoltaic system with improved AC connections and method of making same

DOEpatents

Cioffi, Philip Michael; Todorovic, Maja Harfman; Herzog, Michael Scott; Korman, Charles Steven; Doherty, Donald M.; Johnson, Neil Anthony

2018-02-13

An alternating current (AC) harness for a photovoltaic (PV) system includes a wire assembly having a first end and a second end, the wire assembly having a plurality of lead wires, and at least one AC connection module positioned at a location along a length of the wire assembly between the first end and the second end. Further, the at least one AC connection module includes a first connection terminal electrically coupled to the plurality of lead wires of the wire assembly and constructed to electrically couple the wire assembly with an output of a first PV module of the PV system. The at least one AC connection module also includes a second connection terminal electrically coupled to the plurality of lead wires of the wire assembly and constructed to electrically couple the wire assembly with an output of a second PV module of the PV system.

Acromioclavicular joint injuries in the National Football League: epidemiology and management.

PubMed

Lynch, T Sean; Saltzman, Matthew D; Ghodasra, Jason H; Bilimoria, Karl Y; Bowen, Mark K; Nuber, Gordon W

2013-12-01

Previous studies investigating acromioclavicular (AC) joint injuries in professional American football players have only been reported on quarterbacks during the 1980s and 1990s. These injuries have not been evaluated across all position players in the National Football League (NFL). The purpose of this study was 4-fold: (1) to determine the incidence of AC joint injuries among all NFL position players; (2) to investigate whether player position, competition setting, type of play, and playing surface put an athlete at an increased risk for this type of injury; (3) to determine the incidence of operative and nonoperative management of these injuries; and (4) to compare the time missed for injuries treated nonoperatively to the time missed for injuries requiring surgical intervention. Descriptive epidemiological study. All documented injuries of the AC joint were retrospectively analyzed using the NFL Injury Surveillance System (NFLISS) over a 12-season period from 2000 through 2011. The data were analyzed by the anatomic location, player position, field conditions, type of play, requirement of surgical management, days missed per injury, and injury incidence. Over 12 NFL seasons, there were a total of 2486 shoulder injuries, with 727 (29.2%) of these injuries involving the AC joint. The overall rate of AC joint injuries in these athletes was 26.1 injuries per 10,000 athlete exposures, with the majority of these injuries occurring during game activity on natural grass surfaces (incidence density ratio, 0.79) and most often during passing plays. These injuries occurred most frequently in defensive backs, wide receivers, and special teams players; however, the incidence of these injuries was greatest in quarterbacks (20.9 injuries per 100 players), followed by special teams players (20.7/100) and wide receivers (16.5/100). Overall, these athletes lost a mean of 9.8 days per injury, with quarterbacks losing the most time to injury (mean, 17.3 days). The majority of these injuries were low-grade AC joint sprains that were treated with nonoperative measures; only 13 (1.7%) required surgical management. Players who underwent surgical management lost a mean of 56.2 days. Shoulder injuries, particularly those of the AC joint, occur frequently in the NFL. These injuries can result in time lost but rarely require operative management. Quarterbacks had the highest incidence of injury; however, this incidence is lower than in previous investigations that evaluated these injuries during the 1980s and 1990s.

Magnus-induced ratchet effects for skyrmions interacting with asymmetric substrates

NASA Astrophysics Data System (ADS)

Reichhardt, C.; Ray, D.; Olson Reichhardt, C. J.

2015-07-01

We show using numerical simulations that pronounced ratchet effects can occur for ac driven skyrmions moving over asymmetric quasi-one-dimensional substrates. We find a new type of ratchet effect called a Magnus-induced transverse ratchet that arises when the ac driving force is applied perpendicular rather than parallel to the asymmetry direction of the substrate. This transverse ratchet effect only occurs when the Magnus term is finite, and the threshold ac amplitude needed to induce it decreases as the Magnus term becomes more prominent. Ratcheting skyrmions follow ordered orbits in which the net displacement parallel to the substrate asymmetry direction is quantized. Skyrmion ratchets represent a new ac current-based method for controlling skyrmion positions and motion for spintronic applications.

Histone H3 Lysine 14 (H3K14) Acetylation Facilitates DNA Repair in a Positioned Nucleosome by Stabilizing the Binding of the Chromatin Remodeler RSC (Remodels Structure of Chromatin)*

PubMed Central

Duan, Ming-Rui; Smerdon, Michael J.

2014-01-01

Histone H3 acetylation is induced by UV damage in yeast and may play an important role in regulating the repair of UV photolesions in nucleosome-loaded genomic loci. However, it remains elusive how H3 acetylation facilitates repair. We generated a strongly positioned nucleosome containing homogeneously acetylated H3 at Lys-14 (H3K14ac) and investigated possible mechanisms by which H3K14 acetylation modulates repair. We show that H3K14ac does not alter nucleosome unfolding dynamics or enhance the repair of UV-induced cyclobutane pyrimidine dimers by UV photolyase. Importantly, however, nucleosomes with H3K14ac have a higher affinity for purified chromatin remodeling complex RSC (Remodels the Structure of Chromatin) and show greater cyclobutane pyrimidine dimer repair compared with unacetylated nucleosomes. Our study indicates that, by anchoring RSC, H3K14 acetylation plays an important role in the unfolding of strongly positioned nucleosomes during repair of UV damage. PMID:24515106

The effects of corporate social responsibility on employees' affective commitment: a cross-cultural investigation.

PubMed

Mueller, Karsten; Hattrup, Kate; Spiess, Sven-Oliver; Lin-Hi, Nick

2012-11-01

This study investigated the moderating effects of several Global Leadership and Organizational Behavior Effectiveness (GLOBE) cultural value dimensions on the relationship between employees' perceptions of their organization's social responsibility and their affective organizational commitment. Based on data from a sample of 1,084 employees from 17 countries, results showed that perceived corporate social responsibility (CSR) was positively related to employees' affective commitment (AC), after controlling for individual job satisfaction and gender as well as for nation-level differences in unemployment rates. In addition, several GLOBE value dimensions moderated the effects of CSR on AC. In particular, perceptions of CSR were more positively related to AC in cultures higher in humane orientation, institutional collectivism, ingroup collectivism, and future orientation and in cultures lower in power distance. Implications for future CSR research and cross-cultural human resources management are discussed. (c) 2012 APA, all rights reserved.

76 FR 63899 - Positive Train Control Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-14

...-0028, Notice No. 2] RIN 2130-AC27 Positive Train Control Systems AGENCY: Federal Railroad...-based criteria in order to avoid positive train control (PTC) system implementation on track segments... and Compliance, Staff Director, Signal & Train Control Division, Federal Railroad Administration, Mail...

Prevalence of sensitization to the predatory mite Amblyseius cucumeris as a new occupational allergen in horticulture.

PubMed

Groenewoud, G C M; de Graaf in 't Veld, C; vVan Oorschot-van Nes, A J; de Jong, N W; Vermeulen, A M; van Toorenenbergen, A W; Burdorf, A; de Groot, H; Gerth van Wijk, R

2002-07-01

Protection against thrips, a common pest in bell pepper horticulture is effectively possible without pesticides by using the commercially available predatory mite Amblyzeius cucumeris (Ac). The prevalence of sensitization to Ac among exposed greenhouse employees and its clinical relevance was studied. Four hundred and seventytwo employees were asked to fill in a questionnaire and were tested on location. Next to RAST, skin prick tests (SPTs) were performed with common inhalant allergens, the storage mite Tyrophagus putrescentiae (Tp) which serves as a temporary food source during the cultivation process and Ac. Furthermore, nasal challenge tests with Ac were carried out in 23 sensitized employees. SPTs positive to Ac were found in 109 employees (23%). Work-related symptoms were reported by 76.1%. Sensitization to Tp was found in 62 employees of whom 48 were also sensitized to Ac. Immunoglobulin (Ig)E-mediated allergy to inhalant allergens appeared to be an important risk factor for sensitization to Ac. Employees with rhinitis symptoms showed a significantly higher response to all Ac doses during the nasal challenge test compared with employees without rhinitis symptoms. The predatory mite Ac is a new occupational allergen in horticulture which can cause an IgE-mediated allergy in exposed employees. It is biologically active on the mucous membranes of the nose and therefore clinically relevant for the development of work-related symptoms.

Effects of pole flux distribution in a homopolar linear synchronous machine

NASA Astrophysics Data System (ADS)

Balchin, M. J.; Eastham, J. F.; Coles, P. C.

1994-05-01

Linear forms of synchronous electrical machine are at present being considered as the propulsion means in high-speed, magnetically levitated (Maglev) ground transportation systems. A homopolar form of machine is considered in which the primary member, which carries both ac and dc windings, is supported on the vehicle. Test results and theoretical predictions are presented for a design of machine intended for driving a 100 passenger vehicle at a top speed of 400 km/h. The layout of the dc magnetic circuit is examined to locate the best position for the dc winding from the point of view of minimum core weight. Measurements of flux build-up under the machine at different operating speeds are given for two types of secondary pole: solid and laminated. The solid pole results, which are confirmed theoretically, show that this form of construction is impractical for high-speed drives. Measured motoring characteristics are presented for a short length of machine which simulates conditions at the leading and trailing ends of the full-sized machine. Combination of the results with those from a cylindrical version of the machine make it possible to infer the performance of the full-sized traction machine. This gives 0.8 pf and 0.9 efficiency at 300 km/h, which is much better than the reported performance of a comparable linear induction motor (0.52 pf and 0.82 efficiency). It is therefore concluded that in any projected high-speed Maglev systems, a linear synchronous machine should be the first choice as the propulsion means.

RNAi-derived transgenic resistance to Mungbean yellow mosaic India virus in cowpea.

PubMed

Kumar, Sanjeev; Tanti, Bhaben; Patil, Basavaprabhu L; Mukherjee, Sunil Kumar; Sahoo, Lingaraj

2017-01-01

Cowpea is an important grain legume crop of Africa, Latin America, and Southeast Asia. Leaf curl and golden mosaic diseases caused by Mungbean yellow mosaic India virus (MYMIV) have emerged as most devastating viral diseases of cowpea in Southeast Asia. In this study, we employed RNA interference (RNAi) strategy to control cowpea-infecting MYMIV. For this, we generated transgenic cowpea plants harbouring three different intron hairpin RNAi constructs, containing the AC2, AC4 and fusion of AC2 and AC4 (AC2+AC4) of seven cowpea-infecting begomoviruses. The T0 and T1 transgenic cowpea lines of all the three constructs accumulated transgene-specific siRNAs. Transgenic plants were further assayed up to T1 generations, for resistance to MYMIV using agro-infectious clones. Nearly 100% resistance against MYMIV infection was observed in transgenic lines, expressing AC2-hp and AC2+AC4-hp RNA, when compared with untransformed controls and plants transformed with empty vectors, which developed severe viral disease symptoms within 3 weeks. The AC4-hp RNA expressing lines displayed appearance of milder symptoms after 5 weeks of MYMIV-inoculation. Northern blots revealed a positive correlation between the level of transgene-specific siRNAs accumulation and virus resistance. The MYMIV-resistant transgenic lines accumulated nearly zero or very low titres of viral DNA. The transgenic cowpea plants had normal phenotype with no yield penalty in greenhouse conditions. This is the first demonstration of RNAi-derived resistance to MYMIV in cowpea.

RNAi-derived transgenic resistance to Mungbean yellow mosaic India virus in cowpea

PubMed Central

Kumar, Sanjeev; Tanti, Bhaben; Patil, Basavaprabhu L.; Mukherjee, Sunil Kumar

2017-01-01

Cowpea is an important grain legume crop of Africa, Latin America, and Southeast Asia. Leaf curl and golden mosaic diseases caused by Mungbean yellow mosaic India virus (MYMIV) have emerged as most devastating viral diseases of cowpea in Southeast Asia. In this study, we employed RNA interference (RNAi) strategy to control cowpea-infecting MYMIV. For this, we generated transgenic cowpea plants harbouring three different intron hairpin RNAi constructs, containing the AC2, AC4 and fusion of AC2 and AC4 (AC2+AC4) of seven cowpea-infecting begomoviruses. The T0 and T1 transgenic cowpea lines of all the three constructs accumulated transgene-specific siRNAs. Transgenic plants were further assayed up to T1 generations, for resistance to MYMIV using agro-infectious clones. Nearly 100% resistance against MYMIV infection was observed in transgenic lines, expressing AC2-hp and AC2+AC4-hp RNA, when compared with untransformed controls and plants transformed with empty vectors, which developed severe viral disease symptoms within 3 weeks. The AC4-hp RNA expressing lines displayed appearance of milder symptoms after 5 weeks of MYMIV-inoculation. Northern blots revealed a positive correlation between the level of transgene-specific siRNAs accumulation and virus resistance. The MYMIV-resistant transgenic lines accumulated nearly zero or very low titres of viral DNA. The transgenic cowpea plants had normal phenotype with no yield penalty in greenhouse conditions. This is the first demonstration of RNAi-derived resistance to MYMIV in cowpea. PMID:29077738

Autoimmune Conditions in 235 Hemochromatosis Probands with HFE C282Y Homozygosity and Their First-Degree Relatives.

PubMed

Barton, James C; Barton, J Clayborn

2015-01-01

We performed a retrospective study of autoimmune conditions (ACs) in 235 hemochromatosis probands at diagnosis by analyzing age, sex, ACs, history of first-degree family members with ACs (FH), diabetes, heavy ethanol consumption, elevated serum ALT/AST, nonalcoholic fatty liver disease, viral hepatitis, cirrhosis, iron removed to achieve iron depletion (QFe), and positivity for human leukocyte antigen (HLA) haplotypes A (∗) 01, B (∗) 08; A (∗) 02, B (∗) 44; A (∗) 03, B (∗) 07; A (∗) 03, B (∗) 14; and A (∗) 29, B (∗) 44. There were 138 men (58.7%). Median followup was 19.6 y. One or more of 19 ACs were diagnosed in each of 35 probands (14.9%). Prevalences of Hashimoto's thyroiditis, rheumatoid arthritis, and ankylosing spondylitis were 8.1% (95% CI: [5.1, 12.5]), 1.7% [0.6, 4.6], and 0.0085 [0.0015, 0.0337], respectively. Eighteen probands (7.7%) had a FH. Eight probands with ACs had 9 family members with ACs. In a logistic regression, ACs were less likely in men (odds ratio (OR) 0.3 [0.1, 0.6]) and more likely in probands with a FH (OR 4.1 [1.4, 11.8]). Overall ACs risk was not significantly associated with QFe or HLA haplotypes. Estimated survival of probands with and without ACs did not differ significantly. We conclude that ACs are common in hemochromatosis probands, especially women and probands with a FH.

Autoimmune Conditions in 235 Hemochromatosis Probands with HFE C282Y Homozygosity and Their First-Degree Relatives

PubMed Central

Barton, James C.; Barton, J. Clayborn

2015-01-01

We performed a retrospective study of autoimmune conditions (ACs) in 235 hemochromatosis probands at diagnosis by analyzing age, sex, ACs, history of first-degree family members with ACs (FH), diabetes, heavy ethanol consumption, elevated serum ALT/AST, nonalcoholic fatty liver disease, viral hepatitis, cirrhosis, iron removed to achieve iron depletion (QFe), and positivity for human leukocyte antigen (HLA) haplotypes A∗01, B∗08; A∗02, B∗44; A∗03, B∗07; A∗03, B∗14; and A∗29, B∗44. There were 138 men (58.7%). Median followup was 19.6 y. One or more of 19 ACs were diagnosed in each of 35 probands (14.9%). Prevalences of Hashimoto's thyroiditis, rheumatoid arthritis, and ankylosing spondylitis were 8.1% (95% CI: [5.1, 12.5]), 1.7% [0.6, 4.6], and 0.0085 [0.0015, 0.0337], respectively. Eighteen probands (7.7%) had a FH. Eight probands with ACs had 9 family members with ACs. In a logistic regression, ACs were less likely in men (odds ratio (OR) 0.3 [0.1, 0.6]) and more likely in probands with a FH (OR 4.1 [1.4, 11.8]). Overall ACs risk was not significantly associated with QFe or HLA haplotypes. Estimated survival of probands with and without ACs did not differ significantly. We conclude that ACs are common in hemochromatosis probands, especially women and probands with a FH. PMID:26504855

Binaural Hearing Ability With Bilateral Bone Conduction Stimulation in Subjects With Normal Hearing: Implications for Bone Conduction Hearing Aids.

PubMed

Zeitooni, Mehrnaz; Mäki-Torkko, Elina; Stenfelt, Stefan

The purpose of this study is to evaluate binaural hearing ability in adults with normal hearing when bone conduction (BC) stimulation is bilaterally applied at the bone conduction hearing aid (BCHA) implant position as well as at the audiometric position on the mastoid. The results with BC stimulation are compared with bilateral air conduction (AC) stimulation through earphones. Binaural hearing ability is investigated with tests of spatial release from masking and binaural intelligibility level difference using sentence material, binaural masking level difference with tonal chirp stimulation, and precedence effect using noise stimulus. In all tests, results with bilateral BC stimulation at the BCHA position illustrate an ability to extract binaural cues similar to BC stimulation at the mastoid position. The binaural benefit is overall greater with AC stimulation than BC stimulation at both positions. The binaural benefit for BC stimulation at the mastoid and BCHA position is approximately half in terms of decibels compared with AC stimulation in the speech based tests (spatial release from masking and binaural intelligibility level difference). For binaural masking level difference, the binaural benefit for the two BC positions with chirp signal phase inversion is approximately twice the benefit with inverted phase of the noise. The precedence effect results with BC stimulation at the mastoid and BCHA position are similar for low frequency noise stimulation but differ with high-frequency noise stimulation. The results confirm that binaural hearing processing with bilateral BC stimulation at the mastoid position is also present at the BCHA implant position. This indicates the ability for binaural hearing in patients with good cochlear function when using bilateral BCHAs.

Immunohistochemical study of mucins in human intestinal spirochetosis.

PubMed

Ogata, Sho; Shimizu, Ken; Tominaga, Susumu; Nakanishi, Kuniaki

2017-04-01

Most patients with human intestinal spirochetosis (HIS; a colorectal bacterial infection caused by Brachyspira species) seem asymptomatic, and its pathogenicity remains unclear. Recently, alterations in mucin expression were reported in animal Brachyspira infection. The present question was "Is mucin expression altered in HIS?" Using antibodies for MUCs 1, 2, 4, 5AC, and 6, we immunohistochemically compared 215 specimens from 83 histology-confirmed HIS cases with 106 specimens from 26 non-HIS cases. Positive staining (which included even focal positive staining) was rated "high (+)" or "low (+)." Results were analyzed for 4 categories of lesions, and associations between MUC expression and spirochetal presence were also analyzed. In the "specimens without polyps or adenocarcinoma" category, high (+) MUC2 positivity was more frequent in HIS than in control. In the hyperplasia/serrated polyp category, in HIS (versus control), the MUC5AC positivity rate was lower, whereas high (+) MUC4 positivity was more frequent. In the conventional adenoma category, in HIS (versus control), the MUC1 positivity rate was lower, whereas both high (+) MUC2 positivity and high (+) MUC5AC positivity were less frequent. In the adenocarcinoma category, high (+) MUC2 positivity was more frequent in HIS than in control. Among the above mucins, only MUC1 positivity was significantly associated with an absence of the so-called fringe formation, an absence of spiral organisms within mucus, and an absence of strong immunopositive materials within the epithelial layer and within the subepithelial layer. The results suggest that Brachyspira infection or a related change in the microbiome may alter the large intestine mucin expression profile in humans. Copyright © 2017 Elsevier Inc. All rights reserved.

Artificial neural network and particle swarm optimization for removal of methyl orange by gold nanoparticles loaded on activated carbon and Tamarisk.

PubMed

Ghaedi, M; Ghaedi, A M; Ansari, A; Mohammadi, F; Vafaei, A

2014-11-11

The influence of variables, namely initial dye concentration, adsorbent dosage (g), stirrer speed (rpm) and contact time (min) on the removal of methyl orange (MO) by gold nanoparticles loaded on activated carbon (Au-NP-AC) and Tamarisk were investigated using multiple linear regression (MLR) and artificial neural network (ANN) and the variables were optimized by partial swarm optimization (PSO). Comparison of the results achieved using proposed models, showed the ANN model was better than the MLR model for prediction of methyl orange removal using Au-NP-AC and Tamarisk. Using the optimal ANN model the coefficient of determination (R2) for the test data set were 0.958 and 0.989; mean squared error (MSE) values were 0.00082 and 0.0006 for Au-NP-AC and Tamarisk adsorbent, respectively. In this study a novel and green approach were reported for the synthesis of gold nanoparticle and activated carbon by Tamarisk. This material was characterized using different techniques such as SEM, TEM, XRD and BET. The usability of Au-NP-AC and activated carbon (AC) Tamarisk for the methyl orange from aqueous solutions was investigated. The effect of variables such as pH, initial dye concentration, adsorbent dosage (g) and contact time (min) on methyl orange removal were studied. Fitting the experimental equilibrium data to various isotherm models such as Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich models show the suitability and applicability of the Langmuir model. Kinetic models such as pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion models indicate that the second-order equation and intraparticle diffusion models control the kinetic of the adsorption process. The small amount of proposed Au-NP-AC and activated carbon (0.015 g and 0.75 g) is applicable for successful removal of methyl orange (>98%) in short time (20 min for Au-NP-AC and 45 min for Tamarisk-AC) with high adsorption capacity 161 mg g(-1) for Au-NP-AC and 3.84 mg g(-1) for Tamarisk-AC. Copyright © 2014 Elsevier B.V. All rights reserved.

Artificial neural network and particle swarm optimization for removal of methyl orange by gold nanoparticles loaded on activated carbon and Tamarisk

NASA Astrophysics Data System (ADS)

Ghaedi, M.; Ghaedi, A. M.; Ansari, A.; Mohammadi, F.; Vafaei, A.

2014-11-01

The influence of variables, namely initial dye concentration, adsorbent dosage (g), stirrer speed (rpm) and contact time (min) on the removal of methyl orange (MO) by gold nanoparticles loaded on activated carbon (Au-NP-AC) and Tamarisk were investigated using multiple linear regression (MLR) and artificial neural network (ANN) and the variables were optimized by partial swarm optimization (PSO). Comparison of the results achieved using proposed models, showed the ANN model was better than the MLR model for prediction of methyl orange removal using Au-NP-AC and Tamarisk. Using the optimal ANN model the coefficient of determination (R2) for the test data set were 0.958 and 0.989; mean squared error (MSE) values were 0.00082 and 0.0006 for Au-NP-AC and Tamarisk adsorbent, respectively. In this study a novel and green approach were reported for the synthesis of gold nanoparticle and activated carbon by Tamarisk. This material was characterized using different techniques such as SEM, TEM, XRD and BET. The usability of Au-NP-AC and activated carbon (AC) Tamarisk for the methyl orange from aqueous solutions was investigated. The effect of variables such as pH, initial dye concentration, adsorbent dosage (g) and contact time (min) on methyl orange removal were studied. Fitting the experimental equilibrium data to various isotherm models such as Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich models show the suitability and applicability of the Langmuir model. Kinetic models such as pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion models indicate that the second-order equation and intraparticle diffusion models control the kinetic of the adsorption process. The small amount of proposed Au-NP-AC and activated carbon (0.015 g and 0.75 g) is applicable for successful removal of methyl orange (>98%) in short time (20 min for Au-NP-AC and 45 min for Tamarisk-AC) with high adsorption capacity 161 mg g-1 for Au-NP-AC and 3.84 mg g-1 for Tamarisk-AC.

Impact of Vascular Hemodynamics on Aortic Stenosis Evaluation: New Insights Into the Pathophysiology of Normal Flow-Small Aortic Valve Area-Low Gradient Pattern.

PubMed

Côté, Nancy; Simard, Louis; Zenses, Anne-Sophie; Tastet, Lionel; Shen, Mylène; Clisson, Marine; Clavel, Marie-Annick

2017-07-07

About 50% of normal-flow/low-gradient patients (ie, low mean gradient [MG] or peak aortic jet velocity and small aortic valve area) have severe aortic valve calcification as measured by computed tomography. However, they are considered to have moderate aortic stenosis (AS) in current American College of Cardiology/American Heart Association guidelines. The objective was thus to evaluate the effect of hypertension and reduced arterial compliance (rAC) on MG and V peak measurements. Doppler-echocardiography was performed in 4 sheep with experimentally induced severe and critical AS at: (1) normal aortic pressure, (2) during hypertension, and (3) with rAC. Hypertension and rAC induced a substantial decrease in MG/V peak compared with normal stage (both P ≤0.03) despite a stable transvalvular flow ( P >0.16). Hypertension and rAC resulted in a greater reduction of MG in critical (-42%) compared with severe (-35%) AS ( P ˂0.0001). Comprehensive Doppler-echocardiography and computed tomography were performed in 220 AS patients (mean age: 69±13 years; MG 29±18 mm Hg) with normal flow. The population was divided in 3 groups according to the presence of hypertension and rAC. The slope of the linear association between MG/V peak and aortic valve calcification divided by the cross-sectional area of the aortic annulus was significantly reduced in patients with hypertension and/or rAC compared with normotensive/normal AC patients ( P <0.01). Accordingly, patients with normal-flow/low-gradient and severe aortic valve calcification density were more frequent in hypertension and rAC groups compared with the normotensive/normal-AC group (16% and 12% compared with 2%; P =0.03). Hypertension and rAC are associated with a substantial reduction in MG/V peak for similar aortic valve calcification (ie, similar AS anatomic severity), which may lead to underestimation of AS hemodynamic severity. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Association between the -794 (CATT)5-8  MIF gene polymorphism and susceptibility to acute coronary syndrome in a western Mexican population.

PubMed

Valdés-Alvarado, Emmanuel; Muñoz-Valle, José Francisco; Valle, Yeminia; Sandoval-Pinto, Elena; García-González, Ilian Janet; Valdez-Haro, Angélica; De la Cruz-Mosso, Ulises; Flores-Salinas, Héctor Enrique; Padilla-Gutiérrez, Jorgé Ramón

2014-01-01

The macrophage migration inhibitory factor (MIF) is related to the progression of atherosclerosis, which, in turn, is a key factor in the development of acute coronary syndrome (ACS). MIF has a CATT short tandem repeat (STR) at position -794 that might be involved in its expression rate. The aim of this study was to investigate the association between the -794 (CATT)5-8  MIF gene polymorphism and susceptibility to ACS in a western Mexican population. This research included 200 ACS patients classified according to the criteria of the American College of Cardiology (ACC) and 200 healthy subjects (HS). The -794 (CATT)5-8  MIF gene polymorphism was analyzed using a conventional polymerase chain reaction (PCR) technique. The 6 allele was the most frequent in both groups (ACS: 54% and HS: 57%). The most common genotypes in ACS patients and HS were 6/7 and 6/6, respectively, and a significant association was found between the 6/7 genotype and susceptibility to ACS (68% versus 47% in ACS and HS, resp., P = 0.03). We conclude that the 6/7 genotype of the MIF -794 (CATT)5-8 polymorphism is associated with susceptibility to ACS in a western Mexican population.

A single amino acid substitution modulates low-pH-triggered membrane fusion of GP64 protein in Autographa californica and Bombyx mori nucleopolyhedroviruses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katou, Yasuhiro; Yamada, Hayato; Ikeda, Motoko

2010-09-01

We have previously shown that budded viruses of Bombyx mori nucleopolyhedrovirus (BmNPV) enter the cell cytoplasm but do not migrate into the nuclei of non-permissive Sf9 cells that support a high titer of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) multiplication. Here we show, using the syncytium formation assay, that low-pH-triggered membrane fusion of BmNPV GP64 protein (Bm-GP64) is significantly lower than that of AcMNPV GP64 protein (Ac-GP64). Mutational analyses of GP64 proteins revealed that a single amino acid substitution between Ac-GP64 H155 and Bm-GP64 Y153 can have significant positive or negative effects on membrane fusion activity. Studies using bacmid-based GP64 recombinantmore » AcMNPV harboring point-mutated ac-gp64 and bm-gp64 genes showed that Ac-GP64 H155Y and Bm-GP64 Y153H substitutions decreased and increased, respectively, the multiplication and cell-to-cell spread of progeny viruses. These results indicate that Ac-GP64 H155 facilitates the low-pH-triggered membrane fusion reaction between virus envelopes and endosomal membranes.« less

Expression of adenylyl cyclase types III and VI in human hyperfunctioning thyroid nodules.

PubMed

Celano, M; Arturi, F; Presta, I; Bruno, R; Scarpelli, D; Calvagno, M G; Cristofaro, C; Bulotta, S; Giannasio, P; Sacco, R; Filetti, S; Russo, D

2003-05-30

Hyperfunctioning thyroid nodules are characterized by the presence of spontaneous somatic mutations responsible for constitutive activation of the cAMP pathway. However, alterations affecting other elements of the cAMP signaling system may counteract the effects of the mutations. In this study, the expression of the adenylyl cyclase (AC) types III and VI was investigated by Western blot in 18 hyperfunctioning thyroid nodules; in 12 samples, we also assessed the presence of TSH receptor (TSHR) or gsp mutations and levels of AC VI and III mRNA. We found that the expression of nodular AC VI (but not AC III) was significantly lower (85.1% of normal, P=0.014) than the expression of both adenylyl cycles types of perinodular tissue from the same patients. Slightly, but not significant differences were detected in nodules with or without mutations and AC protein levels generally showed correlation with the levels of the transcripts detected by RT-PCR. In addition, AC III and AC VI expression levels within a given nodule were characterized by a significant positive correlation. These findings indicate that a diminished expression of AC type VI may be part of the mechanisms occurring in the hyperfunctioning nodules, independently of the presence of TSHR or gsp mutations, which influence the resulting phenotype.

A Combined Field and Laboratory Study on Activated Carbon-Based Thin Layer Capping in a PCB-Contaminated Boreal Lake.

PubMed

Abel, Sebastian; Akkanen, Jarkko

2018-04-17

The in situ remediation of aquatic sediments with activated carbon (AC)-based thin layer capping is a promising alternative to traditional methods, such as sediment dredging. Applying a strong sorbent like AC directly to the sediment can greatly reduce the bioavailability of organic pollutants. To evaluate the method under realistic field conditions, a 300 m 2 plot in the PCB-contaminated Lake Kernaalanjärvi, Finland, was amended with an AC cap (1.6 kgAC/m 2 ). The study lake showed highly dynamic sediment movements over the monitoring period of 14 months. This led to poor retention and rapid burial of the AC cap under a layer of contaminated sediment from adjacent sites. As a result, the measured impact of the AC amendment was low: Both the benthic community structure and PCB bioaccumulation were similar on the plot and in surrounding reference sites. Corresponding follow-up laboratory studies using Lumbriculus variegatus and Chironomus riparius showed that long-term remediation success is possible, even when an AC cap is covered with contaminated sediment. To retain a measurable effectiveness (reduction in contaminant bioaccumulation), a sufficient intensity and depth of bioturbation is required. On the other hand, the magnitude of the adverse effect induced by AC correlated positively with the measured remediation success.

Unique capabilities of AC frequency scanning and its implementation on a Mars Organic Molecule Analyzer linear ion trap.

PubMed

Snyder, Dalton T; Kaplan, Desmond A; Danell, Ryan M; van Amerom, Friso H W; Pinnick, Veronica T; Brinckerhoff, William B; Mahaffy, Paul R; Cooks, R Graham

2017-06-21

A limitation of conventional quadrupole ion trap scan modes which use rf amplitude control for mass scanning is that, in order to detect a subset of an ion population, the rest of the ion population must also be interrogated. That is, ions cannot be detected out of order; they must be detected in order of either increasing or decreasing mass-to-charge (m/z). However, an ion trap operated in the ac frequency scan mode, where the rf amplitude is kept constant and instead the ac frequency is used for mass-selective operations, has no such limitation because any variation in the ac frequency affects only the subset of ions whose secular frequencies match the perturbation frequency. Hence, an ion trap operated in the ac frequency scan mode can perform any arbitrary mass scan, as well as a sequence of scans, using a single ion injection; we demonstrate both capabilities here. Combining these two capabilities, we demonstrate the acquisition of a full mass spectrum, a product ion spectrum, and a second generation product ion spectrum using a single ion injection event. We further demonstrate a "segmented scan" in which different mass ranges are interrogated at different rf amplitudes in order to improve resolution over a portion of the mass range, and a "periodic scan" in which ions are continuously introduced into the ion trap to achieve a nearly 100% duty cycle. These unique scan modes, along with other characteristics of ac frequency scanning, are particularly appropriate for miniature ion trap mass spectrometers. Hence, implementation of ac frequency scanning on a prototype of the Mars Organic Molecule Analyzer mass spectrometer is also described.

Molecular modeling of methyl-α-Neu5Ac analogues docked against cholera toxin--a molecular dynamics study.

PubMed

Blessy, J Jino; Sharmila, D Jeya Sundara

2015-02-01

Molecular modeling of synthetic methyl-α-Neu5Ac analogues modified in C-9 position was investigated by molecular docking and molecular dynamics (MD) simulation methods. Methyl-α-Neu5Ac analogues were docked against cholera toxin (CT) B subunit protein and MD simulations were carried out for three Methyl-α-Neu5Ac analogue-CT complexes (30, 10 and 10 ns) to estimate the binding activity of cholera toxin-Methyl-α-Neu5Ac analogues using OPLS_2005 force field. In this study, direct and water mediated hydrogen bonds play a vital role that exist between the methyl-α-9-N-benzoyl-amino-9-deoxy-Neu5Ac (BENZ)-cholera toxin active site residues. The Energy plot, RMSD and RMSF explain that the simulation was stable throughout the simulation run. Transition of phi, psi and omega angle for the complex was calculated. Molecular docking studies could be able to identify the binding mode of methyl-α-Neu5Ac analogues in the binding site of cholera toxin B subunit protein. MD simulation for Methyl-α-9-N-benzoyl-amino-9-deoxy-Neu5Ac (BENZ), Methyl-α-9-N-acetyl-9-deoxy-9-amino-Neu5Ac and Methyl-α-9-N-biphenyl-4-acetyl-deoxy-amino-Neu5Ac complex with CT B subunit protein was carried out, which explains the stable nature of interaction. These methyl-α-Neu5Ac analogues that have computationally acceptable pharmacological properties may be used as novel candidates for drug design for cholera disease.

Evaluation of the impact of metal artifacts in CT-based attenuation correction of positron emission tomography scans

NASA Astrophysics Data System (ADS)

Wu, Jay; Shih, Cheng-Ting; Chang, Shu-Jun; Huang, Tzung-Chi; Chen, Chuan-Lin; Wu, Tung Hsin

2011-08-01

The quantitative ability of PET/CT allows the widespread use in clinical research and cancer staging. However, metal artifacts induced by high-density metal objects degrade the quality of CT images. These artifacts also propagate to the corresponding PET image and cause a false increase of 18F-FDG uptake near the metal implants when the CT-based attenuation correction (AC) is performed. In this study, we applied a model-based metal artifact reduction (MAR) algorithm to reduce the dark and bright streaks in the CT image and compared the differences between PET images with the general CT-based AC (G-AC) and the MAR-corrected-CT AC (MAR-AC). Results showed that the MAR algorithm effectively reduced the metal artifacts in the CT images of the ACR flangeless phantom and two clinical cases. The MAR-AC also removed the false-positive hot spot near the metal implants of the PET images. We conclude that the MAR-AC could be applied in clinical practice to improve the quantitative accuracy of PET images. Additionally, further use of PET/CT fusion images with metal artifact correction could be more valuable for diagnosis.

p85α recruitment by the CD300f phosphatidylserine receptor mediates apoptotic cell clearance required for autoimmunity suppression

NASA Astrophysics Data System (ADS)

Tian, Linjie; Choi, Seung-Chul; Murakami, Yousuke; Allen, Joselyn; Morse, Herbert C., III; Qi, Chen-Feng; Krzewski, Konrad; Coligan, John E.

2014-01-01

Apoptotic cell (AC) clearance is essential for immune homeostasis. Here we show that mouse CD300f (CLM-1) recognizes outer membrane-exposed phosphatidylserine, and regulates the phagocytosis of ACs. CD300f accumulates in phagocytic cups at AC contact sites. Phosphorylation within CD300f cytoplasmic tail tyrosine-based motifs initiates signals that positively or negatively regulate AC phagocytosis. Y276 phosphorylation is necessary for enhanced CD300f-mediated phagocytosis through the recruitment of the p85α regulatory subunit of phosphatidylinositol-3-kinase (PI3K). CD300f-PI3K association leads to activation of downstream Rac/Cdc42 GTPase and mediates changes of F-actin that drive AC engulfment. Importantly, primary macrophages from CD300f-deficient mice have impaired phagocytosis of ACs. The biological consequence of CD300f deficiency is predisposition to autoimmune disease development, as FcγRIIB-deficient mice develop a systemic lupus erythematosus-like disease at a markedly accelerated rate if CD300f is absent. In this report we identify the mechanism and role of CD300f in AC phagocytosis and maintenance of immune homeostasis.

Secapin, a bee venom peptide, exhibits anti-fibrinolytic, anti-elastolytic, and anti-microbial activities.

PubMed

Lee, Kwang Sik; Kim, Bo Yeon; Yoon, Hyung Joo; Choi, Yong Soo; Jin, Byung Rae

2016-10-01

Bee venom contains a variety of peptide constituents that have various biological, toxicological, and pharmacological actions. However, the biological actions of secapin, a venom peptide in bee venom, remain largely unknown. Here, we provide the evidence that Asiatic honeybee (Apis cerana) secapin (AcSecapin-1) exhibits anti-fibrinolytic, anti-elastolytic, and anti-microbial activities. The recombinant mature AcSecapin-1 peptide was expressed in baculovirus-infected insect cells. AcSecapin-1 functions as a serine protease inhibitor-like peptide that has inhibitory effects against plasmin, elastases, microbial serine proteases, trypsin, and chymotrypsin. Consistent with these functions, AcSecapin-1 inhibited the plasmin-mediated degradation of fibrin to fibrin degradation products, thus indicating the role of AcSecapin-1 as an anti-fibrinolytic agent. AcSecapin-1 also inhibited both human neutrophil and porcine pancreatic elastases. Furthermore, AcSecapin-1 bound to bacterial and fungal surfaces and exhibited anti-microbial activity against fungi and gram-positive and gram-negative bacteria. Taken together, our data demonstrated that the bee venom peptide secapin has multifunctional roles as an anti-fibrinolytic agent during fibrinolysis and an anti-microbial agent in the innate immune response. Copyright © 2016 Elsevier Ltd. All rights reserved.

Positive train control shared network.

DOT National Transportation Integrated Search

2015-05-01

The Interoperable Train Control (ITC) Positive : Train Control (PTC) Shared Network (IPSN) : project investigated anticipated industry benefits : and the level of support for the development of : a hosted technological platform for PTC : messaging ac...

77 FR 28285 - Positive Train Control Systems (RRR)

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-14

...-0028, Notice No. 3] RIN 2130-AC27 Positive Train Control Systems (RRR) AGENCY: Federal Railroad... railroads to install positive train control (PTC) systems. This final rule removes regulatory provisions... Safety Assurance and Compliance, Staff Director, Signal & Train Control Division, Federal Railroad...

76 FR 52918 - Positive Train Control Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-24

...-0028, Notice No. 1] RIN 2130-AC27 Positive Train Control Systems AGENCY: Federal Railroad... that requires certain passenger and freight railroads to install positive train control (PTC) systems...: Thomas McFarlin, Office of Safety Assurance and Compliance, Staff Director, Signal & Train Control...

Building a Database for the Historical Analysis of the General Chemistry Curriculum Using ACS General Chemistry Exams as Artifacts

ERIC Educational Resources Information Center

Luxford, Cynthia J.; Linenberger, Kimberly J.; Raker, Jeffrey R.; Baluyut, John Y.; Reed, Jessica J.; De Silva, Chamila; Holme, Thomas A.

2015-01-01

As a discipline, chemistry enjoys a unique position. While many academic areas prepared "cooperative examinations" in the 1930s, only chemistry maintained the activity within what has become the ACS Examinations Institute. As a result, the long-term existence of community-built, norm-referenced, standardized exams provides a historical…

Category (CAT) IIIb Level 1 Test Plan for Global Positioning System (GPS)

DTIC Science & Technology

1993-09-01

applications. CAT 11Tb is defined in Advisory Circular ( AC ) 120-28C [1] as "a precision instrument approach and landing with no decision height (DH), or...2) FAA AC 20-57A (Automatic Landing Systems) [31, AC 120-28C (Criteria for Approval of CAT III Landing Weather Minima) [I] and the FAA tunnel-in...AD-A274 098I I~II l~iiUIRII 11111ilIII2 DOT/FAA/RD-93/21 Category ( CAT ) IIb Level 1 MTR 93W0000102 Research and Test Plan for Global Development

Design versions of HTS three-phase cables with the minimized value of AC losses

NASA Astrophysics Data System (ADS)

Altov, V. A.; Balashov, N. N.; Degtyarenko, P. N.; Ivanov, S. S.; Kopylov, S. I.; Lipa, DA; Samoilenkov, S. V.; Sytnikov, V. E.; Zheltov, V. V.

2018-03-01

Design versions of HTS three-phase cables consisting of 2G HTS tapes have been investigated by the numerical simulation method with the aim of AC losses minimization. Two design versions of cables with the coaxial and extended rectangular cross-section shape are considered – the non-sectioned and sectioned one. In the latter each cable phase consists of sections connected in parallel. The optimal dimensions of sections and order of their alteration are chosen by appropriate calculations. The model used takes into account the current distribution between the sections and its non-uniformity within each single HTS tape as well. The following characteristics are varied: design version, dimension, positioning of extra copper layer in a cable, design of HTS tapes themselves and their mutual position. The dependence of AC losses on the latter two characteristics is considered in details, and the examples of cable designs optimized by the total set of characteristics for the medium class of voltages (10 – 60 kV) are given. At the critical current JC=5.1 кA per phase and current amplitudes lower than 0.85JC, the level of total AC losses does not exceed the natural cryostat heat losses.

Inadequately marketing our brand: Medical student awareness of acute care surgery.

PubMed

Montgomery, Stephanie C; Privette, Alicia R; Ferguson, Pamela L; Mirdamadi, Meena; Fakhry, Samir M

2015-11-01

Despite focused national efforts to promote acute care surgery (ACS), little is known about medical student awareness of ACS as a career choice. The impending shortage of general surgeons emphasizes the need to increase interest in this comprehensive surgical specialty. The goal of this study was to determine whether students would be more likely to consider choosing ACS if they were aware of the specialty and its benefits. A survey was distributed electronically to medical students at our institution, a Level I trauma center with an active ACS service. The survey asked questions regarding specialty choice and factors that were used in making that decision. Also included were questions regarding their familiarity and affinity for ACS. The survey was returned by 518 students. Each medical school year was proportionately represented. Twenty-one percent of the students reported surgery as their career choice; however, women were half as likely to choose surgery as men. When asked to define ACS, 23% of all students gave the correct response. Only 8.9% of the students in the preclinical years correctly defined ACS. Even in the clinical years, 54% were unaware of ACS as a specialty. Students reported that the top factors that influenced their choice were controllable lifestyle, predictable schedule, and a positive medical school role model. When asked to identify what would make ACS appealing, a 50-hour work week was deemed most influential. When given the definition of ACS with approximate pay and on-call hours, 41.5% of the students and 75% of those interested in surgery would be likely to choose ACS as a career. This study highlights that awareness of ACS as a specialty is lacking. This may reflect inadequate marketing of our "brand" both locally and nationally. Focused efforts at familiarizing students with ACS and increased role modeling may increase interest in ACS.

Artemisia capillaris inhibits atopic dermatitis-like skin lesions in Dermatophagoides farinae-sensitized Nc/Nga mice

PubMed Central

2014-01-01

Background Artemisia capillaries Thunb. (AC) has been used to treat inflammatory and hepatic disorders such as hepatic injury, hepatic fibrosis and hepatitis. However, the efficacy of AC against atopic dermatitis (AD), an inflammatory disease, has not been examined. In the present study, AC was evaluated for anti-inflammatory and anti-AD effects using both in vitro and in vivo systems. Methods The contents of six compounds (chlorogenic acid, caffeic acid, isochlorogenic acid A, hyperoside, isoquercitrin and scoparone) in AC were simultaneously assayed using HPLC system. To evaluate the anti-inflammatory effect of AC, NO production was measured in RAW264.7 cell stimulated with 1 μg/mL LPS. Histamine levels were assayed in MC/9 cells stimulated with 50 nM PMA and 1 μM A23187. To examine the role of AC in vivo, AC (10 mg/mouse/day) was topically applied for four weeks the back and ears of Dermatophagoides farinae-sensitized Nc/Nga mice. Protopic ointment (0.1% tacrolimus) was used as a positive control. Results The contents of the six components in AC range from 0.44 to 43.14 mg/g. Chlorogenic acid (21.06 ± 0.08 mg/g) and isochlorogenic acid A (43.14 ± 0.12 mg/g) were major components in AC. AC inhibited NO and histamine production in cells respectively. In D. farinae-sensitized Nc/Nga mice, the topical application of AC reduced dermatitis scores, hemorrhage, hypertrophy and hyperkeratosis of the epidermis in the dorsal skin and ear. The treatment of AC also reduced the plasma levels of histamine (1.5 fold) and IgE (1.4 fold). Conclusions Our results suggest that AC should be explored as a potential therapeutic agent to treat atopic dermatitis and analysis by HPLC will help to improve the quality of AC. PMID:24624888

Early histological, hormonal, and molecular changes during pineapple (Ananas comosus (L.) Merrill) artificial flowering induction.

PubMed

Espinosa, Maita Eulalia Ávila; Moreira, Rafael Oliveira; Lima, André Almeida; Ságio, Solange Aparecida; Barreto, Horllys Gomes; Luiz, Sara Lazara Pérez; Abreu, Carlos Eduardo Aragón; Yanes-Paz, Ermis; Ruíz, Yanelis Capdesuñer; González-Olmedo, Justo Lorenzo; Chalfun-Júnior, Antonio

2017-02-01

Natural flowering can cause serious scheduling problems in the pineapple (Ananas comosus) industry and increase harvest costs. Pineapple flowering is thought to be triggered by increased ethylene levels and artificial forcing of pineapple flowering is a common practice to promote flowering synchronisation. However, little is known about the early hormonal and molecular changes of pineapple flowering induction and development. Here, we aimed to analyse the molecular, hormonal, and histological changes during artificial pineapple flowering by Ethrel ® 48 treatment. Histological analyses of the shoot apical meristem, leaf gibberellic acid (GA 3 ), and ethylene quantification were carried out during the first 72h after Ethrel ® 48 treatment. Expression profiles from ethylene biosynthesis (AcACS2 and AcACO1), gibberellin metabolism (AcGA2-ox1 and AcDELLA1), and flower development (FT-like gene (AcFT), LFY-like gene (AcLFY), and a PISTILLATA-like gene (AcPI)) genes were analysed during the first 24h after Ethrel ® 48 treatment. Differentiation processes of the shoot apical meristem into flower buds were already present in the first 72h after Ethrel ® 48 treatment. Ethrel ® 48 lead to a reduction in GA 3 levels, probably triggered by elevated ethylene levels and the positive regulation AcGA2-ox1. AcLFY activation upon Ethrel ® 48 may also have contributed to the reduction of GA 3 levels and, along with the up-regulation of AcPI, are probably associated with the flower induction activation. AcFT and AcDELLA1 do not seem to be regulated by GA 3 and ethylene. Decreased GA 3 and increased ethylene levels suggest an accumulation of AcDELLA1, which may display an important role in pineapple flowering induction. Thus, this study shows that molecular, hormonal, and histological changes are present right after Ethrel ® 48 treatment, providing new insights into how pineapple flowering occurs under natural conditions. Copyright © 2016 Elsevier GmbH. All rights reserved.

Comparative transcriptome analysis reveals distinct ethylene-independent regulation of ripening in response to low temperature in kiwifruit.

PubMed

Asiche, William O; Mitalo, Oscar W; Kasahara, Yuka; Tosa, Yasuaki; Mworia, Eric G; Owino, Willis O; Ushijima, Koichiro; Nakano, Ryohei; Yano, Kentaro; Kubo, Yasutaka

2018-03-21

Kiwifruit are classified as climacteric since exogenous ethylene (or its analogue propylene) induces rapid ripening accompanied by ethylene production under positive feedback regulation. However, most of the ripening-associated changes (Phase 1 ripening) in kiwifruit during storage and on-vine occur largely in the absence of any detectable ethylene. This ripening behavior is often attributed to basal levels of system I ethylene, although it is suggested to be modulated by low temperature. To elucidate the mechanisms regulating Phase 1 ripening in kiwifruit, a comparative transcriptome analysis using fruit continuously exposed to propylene (at 20 °C), and during storage at 5 °C and 20 °C was conducted. Propylene exposure induced kiwifruit softening, reduction of titratable acidity (TA), increase in soluble solids content (SSC) and ethylene production within 5 days. During storage, softening and reduction of TA occurred faster in fruit at 5 °C compared to 20 °C although no endogenous ethylene production was detected. Transcriptome analysis revealed 3761 ripening-related differentially expressed genes (DEGs), of which 2742 were up-regulated by propylene while 1058 were up-regulated by low temperature. Propylene exclusively up-regulated 2112 DEGs including those associated with ethylene biosynthesis and ripening such as AcACS1, AcACO2, AcPL1, AcXET1, Acβ-GAL, AcAAT, AcERF6 and AcNAC7. Similarly, low temperature exclusively up-regulated 467 DEGS including AcACO3, AcPL2, AcPMEi, AcADH, Acβ-AMY2, AcGA2ox2, AcNAC5 and AcbZIP2 among others. A considerable number of DEGs such as AcPG, AcEXP1, AcXET2, Acβ-AMY1, AcGA2ox1, AcNAC6, AcMADS1 and AcbZIP1 were up-regulated by either propylene or low temperature. Frequent 1-MCP treatments failed to inhibit the accelerated ripening and up-regulation of associated DEGs by low temperature indicating that the changes were independent of ethylene. On-vine kiwifruit ripening proceeded in the absence of any detectable endogenous ethylene production, and coincided with increased expression of low temperature-responsive DEGs as well as the decrease in environmental temperature. These results indicate that kiwifruit possess both ethylene-dependent and low temperature-modulated ripening mechanisms that are distinct and independent of each other. The current work provides a foundation for elaborating the control of these two ripening mechanisms in kiwifruit.

Impedance Spectroscopy and AC Conductivity Studies of Bulk 3-Amino-7-(dimethylamino)-2-methyl-hydrochloride

NASA Astrophysics Data System (ADS)

El-Shabaan, M. M.

2018-02-01

Impedance spectroscopy and alternating-current (AC) conductivity (σ AC) studies of bulk 3-amino-7-(dimethylamino)-2-methyl-hydrochloride (neutral red, NR) have been carried out over the temperature (T) range from 303 K to 383 K and frequency (f) range from 0.5 kHz to 5 MHz. Dielectric data were analyzed using the complex impedance (Z *) and complex electric modulus (M *) for bulk NR at various temperatures. The impedance loss peaks were found to shift towards high frequencies, indicating an increase in the relaxation time (τ 0) and loss in the material, with increasing temperature. For each temperature, a single depressed semicircle was observed at high frequencies, originating from the bulk transport, and a spike in the low-frequency region, resulting from the electrode effect. Fitting of these curves yielded an equivalent circuit containing a parallel combination of a resistance R and constant-phase element (CPE) Q. The carrier transport in bulk NR is governed by the correlated barrier hopping (CBH) mechanism, some parameters of which, such as the maximum barrier height (W M), charge density (N), and hopping distance (r), were determined as functions of both temperature and frequency. The frequency dependence of σ AC at different temperatures indicated that the conduction in bulk NR is a thermally activated process. The σ AC value at different frequencies increased linearly with temperature.

Scalable Heuristics for Planning, Placement and Sizing of Flexible AC Transmission System Devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frolov, Vladmir; Backhaus, Scott N.; Chertkov, Michael

Aiming to relieve transmission grid congestion and improve or extend feasibility domain of the operations, we build optimization heuristics, generalizing standard AC Optimal Power Flow (OPF), for placement and sizing of Flexible Alternating Current Transmission System (FACTS) devices of the Series Compensation (SC) and Static VAR Compensation (SVC) type. One use of these devices is in resolving the case when the AC OPF solution does not exist because of congestion. Another application is developing a long-term investment strategy for placement and sizing of the SC and SVC devices to reduce operational cost and improve power system operation. SC and SVCmore » devices are represented by modification of the transmission line inductances and reactive power nodal corrections respectively. We find one placement and sizing of FACTs devices for multiple scenarios and optimal settings for each scenario simultaneously. Our solution of the nonlinear and nonconvex generalized AC-OPF consists of building a convergent sequence of convex optimizations containing only linear constraints and shows good computational scaling to larger systems. The approach is illustrated on single- and multi-scenario examples of the Matpower case-30 model.« less

Evaluation of shuttle solid rocket booster case materials. Corrosion and stress corrosion susceptibility of several high temperature materials

NASA Technical Reports Server (NTRS)

Pionke, L. J.; Garland, K. C.

1973-01-01

Candidate alloys for the Shuttle Solid Rocket Booster (SRB) case were tested under simulated service conditions to define subcritical flaw growth behavior under both sustained and cyclic loading conditions. The materials evaluated were D6AC and 18 Ni maraging steel, both heat treated to a nominal yield strength of 1380 MN/sq m (200 ksi). The sustained load tests were conducted by exposing precracked, stressed specimens of both alloys to alternate immersion in synthetic sea water. It was found that the corrosion and stress corrosion resistance of the 18 Ni maraging steel were superior to that of the D6AC steel under these test conditions. It was also found that austenitizing temperature had little influence on the threshold stress intensity of the D6AC. The cyclic tests were conducted by subjecting precracked surface-flawed specimens of both alloys to repeated load/thermal/environmental profiles which were selected to simulate the SRB missions. It was found that linear removal operations that involve heating to 589 K (600 F) cause a decrease in cyclic life of D6AC steel relative to those tests conducted with no thermal cycling.

The effectiveness of stationary automobiles as shelters in accidental releases of toxic materials

NASA Astrophysics Data System (ADS)

Engelmann, Rudolf J.; Pendergrass, William R.; White, J. Randy; Hall, Mark E.

The protection offered occupants of stationary automobiles against airborne gases and respirable particles, such as might result from an accidental release, was measured and found to be substantial. For the four autos tested with the air conditioning (AC) system on and in recirculate position, the equilibrium ratios of inside/outside concentrations ( I/ O) for 2-μm diameter particles were less than 0.2, and some ratios were as small as 0.014. With both the AC compressor and the system fan off, the I/ O for five autos ranged from 0.04 to 0.18. These low ratios are primarily a result of deposition within the autos. However, three of the five autos had substantially higher I/ O ratios when the AC fan was on than when off, indicating that for some autos the AC caused significant added intake of outside air. Air exchange rates for the five stationary autos were on the order of 0.5h -1 with AC off, and 2.5 h -1 with AC on.

Tadpole-shaped lateralized parietal atretic cephalocele associated with an ipsilateral lacrimal gland fistula and schizencephalic clefts.

PubMed

Murakami, Nobuya; Morioka, Takato; Suzuki, Satoshi O; Mukae, Nobutaka; Hashiguchi, Kimiaki; Iihara, Koji

2017-02-01

Parietal atretic cephalocele (AC) and its associated intracranial venous anomalies, such as vertical embryonic positioning of the straight sinus (VEP of SS), have, in previous reports, been exclusively restricted to the midline. We report a patient with lateralized parietal AC on the right side. The AC was in the shape of a tadpole, with a large head and a long tail, extending to the proximity of the right external canthus, where a lacrimal gland fistula was observed. The superior sagittal sinus and VEP of SS were also displaced to the right side, although the sagittal suture was located at the midline. Schizencephalic clefts in the right posterior cortex were also observed. The parietal AC, which was initially located in the midline, could conceivably have been displaced to the right side by other developmental processes. However, the relationship between lateralized AC and associated multiple anomalies on the ipsilateral side is difficult to explain monogenetically. Our case study indicates that AC might have a broader spectrum of clinical symptoms than was once thought to be the case.

Oral lichen planus patients exhibit consistent chromosomal numerical aberrations: A follow-up analysis.

PubMed

Yahalom, Ran; Yarom, Noam; Shani, Tali; Amariglio, Ninet; Kaplan, Ilana; Trakhtenbrot, Luba; Hirshberg, Abraham

2016-04-01

Oral lichen planus (OLP) carries an increased risk for malignant transformation with aneuploid cells (ACs) being found in brush samples of a quarter of patients with OLP. Patients with OLP were followed and repeated brush samples were simultaneously analyzed for morphology and fluorescent in situ hybridization (FISH) using centromeric probes for chromosomes 2 and 8. Three patients with a high proportion of ACs developed oral cancer. Fifteen patients had ≥1% ACs (13 in affected sites and 2 in nonaffected sites), whereas only 2 of the 15 patients with <1% ACs in the first sample had ≥1% ACs in the second sample. A strong positive correlation between the results of the initial and repeated samples was found. High proportion of ACs in brush samples from patients with OLP may imply an impending malignant transformation. As FISH analysis is consistent over time, it can be used to identify a subgroup of patients who would require close follow-up. © 2015 Wiley Periodicals, Inc. Head Neck 38: E741-E746, 2016. © 2015 Wiley Periodicals, Inc.

The Interactive Effects of the Capability for Suicide and Major Depressive Episodes on Suicidal Behavior in a Military Sample

PubMed Central

Chu, Carol; Podlogar, Matthew; Hagan, Christopher R.; Buchman-Schmitt, Jennifer M.; Silva, Caroline; Chiurliza, Bruno; Hames, Jennifer L.; Stanley, Ian H.; Lim, LTC Ingrid C.; Joiner, Thomas E.

2015-01-01

Major depressive symptoms represent a significant risk for suicidal ideation and behavior. Given that suicide is fearsome, the interpersonal theory of suicide proposes that individuals who engage in suicidal behavior possess not only the desire to die, but also the acquired capability (AC) for suicide. This study examined whether major depressive episodes (MDEs) may be particularly relevant to suicidal behavior when considered in the context of AC. History of MDEs, AC, and suicide attempt history were examined in a large (n=3,377) sample of military members. Data were analyzed using hierarchical multiple regression. Results indicated that among individuals with high AC, the number of MDEs was significantly, positively associated with number of previous suicide attempts; MDEs were not significantly related to suicide attempt history among individuals with low AC. Findings held in the presence of robust covariates associated with suicidal behavior. Findings suggest that a history of MDEs alone may not indicate severe suicide risk – increased AC for suicide appears necessary for increased suicide risk. Implications for suicide treatment and prevention in military personnel are discussed. PMID:26834299

Association Study between an SNP in CD147 and Its Expression With Acute Coronary Syndrome in a Jiangsu Chinese Population.

PubMed

Yan, Jinchuan; Mao, Yu; Wang, Cuiping; Wang, Zhongqun

2015-10-01

CD147 is an important molecule in the inflammation and proteolysis process. This molecule crucially contributes to the initial and progression of atherosclerotic lesions. A single nucleotide polymorphism in CD147 gene, the rs8259 T/A in the 3'-untranslated region, is responsible for its expression in various cells. This study assessed whether the genetic variation rs8259 is associated with acute coronary syndrome (ACS) and CD147. A total of 943 ACS subjects and 439 stable angina subjects, and 851 controls were genotyped for rs8259 polymorphism by polymerase chain reaction restriction fragment length polymorphism and DNA-sequencing method. Plasma soluble CD147 (sCD147) level was measured by enzyme-linked immunosorbent assay. CD147 mRNA and protein expression in peripheral blood mononuclear cells were tested by real-time quantitative polymerase chain reaction and western blot, respectively. We found that TT genotype and T-allele frequency of CD147 rs8259 in ACS patients were much lower than the other patient groups. Significant difference was not observed between stable angina and controls. CD147 T allele was negatively related to ACS. ACS patients exhibited the highest CD147 expression in peripheral blood mononuclear cells and plasma sCD147 level. The plasma sCD147 levels in the culprit vessel were higher than those in the radial artery. In ACS patients, AA gene carriers had the highest CD147 levels, whereas TT gene carriers had the lowest CD147 levels. Linear regression analysis showed that genotypes and disease conditions contributed 49% to the change of the plasma CD147 level. These results suggested that the single nucleotide polymorphism of CD147 gene rs8259 T/A was associated with ACS susceptibility. Allele T gene may decrease the relative risk of suffering from ACS through downregulation of CD147 expression.

Magnus-induced ratchet effects for skyrmions interacting with asymmetric substrates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reichhardt, C.; Ray, D.; Reichhardt, C. J. Olson

2015-07-31

We show using numerical simulations that pronounced ratchet effects can occur for ac driven skyrmions moving over asymmetric quasi-one-dimensional substrates. We find a new type of ratchet effect called a Magnus-induced transverse ratchet that arises when the ac driving force is applied perpendicular rather than parallel to the asymmetry direction of the substrate. This transverse ratchet effect only occurs when the Magnus term is finite, and the threshold ac amplitude needed to induce it decreases as the Magnus term becomes more prominent. Ratcheting skyrmions follow ordered orbits in which the net displacement parallel to the substrate asymmetry direction is quantized.more » As a result, skyrmion ratchets represent a new ac current-based method for controlling skyrmion positions and motion for spintronic applications.« less

A Feature-Based Approach to Modeling Protein–DNA Interactions

PubMed Central

Segal, Eran

2008-01-01

Transcription factor (TF) binding to its DNA target site is a fundamental regulatory interaction. The most common model used to represent TF binding specificities is a position specific scoring matrix (PSSM), which assumes independence between binding positions. However, in many cases, this simplifying assumption does not hold. Here, we present feature motif models (FMMs), a novel probabilistic method for modeling TF–DNA interactions, based on log-linear models. Our approach uses sequence features to represent TF binding specificities, where each feature may span multiple positions. We develop the mathematical formulation of our model and devise an algorithm for learning its structural features from binding site data. We also developed a discriminative motif finder, which discovers de novo FMMs that are enriched in target sets of sequences compared to background sets. We evaluate our approach on synthetic data and on the widely used TF chromatin immunoprecipitation (ChIP) dataset of Harbison et al. We then apply our algorithm to high-throughput TF ChIP data from mouse and human, reveal sequence features that are present in the binding specificities of mouse and human TFs, and show that FMMs explain TF binding significantly better than PSSMs. Our FMM learning and motif finder software are available at http://genie.weizmann.ac.il/. PMID:18725950

Direct Evaluation of MR-Derived Attenuation Correction Maps for PET/MR of the Mouse Myocardium

NASA Astrophysics Data System (ADS)

Evans, Eleanor; Buonincontri, Guido; Hawkes, Rob C.; Ansorge, Richard E.; Carpenter, T. Adrian; Sawiak, Stephen J.

2016-02-01

Attenuation correction (AC) must be applied to provide accurate measurements of PET tracer activity concentrations. Due to the limited space available in PET/MR scanners, MR-derived AC (MRAC) is used as a substitute for transmission source scanning. In preclinical PET/MR, there has been limited exploration of MRAC, as the magnitude of AC in murine imaging is much smaller than that required in clinical scans. We investigated if a simple 2 class (air and tissue) segmentation-based MRAC approach could provide adequate AC for mouse PET imaging. To construct the default MRAC μ maps, MR images were thresholded and segmented using ASIPRO software (Siemens Molecular Imaging), which defined the mouse body region as tissue with a uniform linear attenuation coefficient ( μ) of 0.095 cm - 1, and the background and lungs as air, with a μ value of 0 cm - 1. To correct for the misassignment of the lungs as air, two further MRAC μ maps were tested: 1) MRAC (tissue) approach, which changed the lung region designation from air to tissue ( μ = 0.095 cm - 1) and 2) MRAC (lung) approach, which treated the lungs as an additional tissue class, with a μ value of 0.032 cm - 1. All μ maps were then forward projected to create attenuation sinograms for image reconstruction. Standard uptake value (SUV) maps of the myocardium were derived for 10 mice with and without AC applied using gold standard transmission scans (TXAC), the 3 MRAC methods and PET emission scans (EmAC). All AC methods produced significantly different myocardial SUVs to those produced without AC when compared across the mouse group ( ). Similar ( ) SUV were derived with all AC methods, with the best agreement to TXAC achieved using the MRAC (tissue) method, giving a mean difference of 0.9±2.4% in myocardial SUV when compared across all mice. SUV differences of up to 40%, however, were seen in areas adjacent to the RF coil in images produced using all AC methods, except for TXAC. A 2 class MRAC approach can therefore provide acceptable AC for myocardial imaging in mice, although additional CT templates of coils and animals beds would be recommended to further improve image quantification.

De Novo Design and Experimental Characterization of Ultrashort Self-Associating Peptides

PubMed Central

Xue, Bo; Robinson, Robert C.; Hauser, Charlotte A. E.; Floudas, Christodoulos A.

2014-01-01

Self-association is a common phenomenon in biology and one that can have positive and negative impacts, from the construction of the architectural cytoskeleton of cells to the formation of fibrils in amyloid diseases. Understanding the nature and mechanisms of self-association is important for modulating these systems and in creating biologically-inspired materials. Here, we present a two-stage de novo peptide design framework that can generate novel self-associating peptide systems. The first stage uses a simulated multimeric template structure as input into the optimization-based Sequence Selection to generate low potential energy sequences. The second stage is a computational validation procedure that calculates Fold Specificity and/or Approximate Association Affinity (K*association) based on metrics that we have devised for multimeric systems. This framework was applied to the design of self-associating tripeptides using the known self-associating tripeptide, Ac-IVD, as a structural template. Six computationally predicted tripeptides (Ac-LVE, Ac-YYD, Ac-LLE, Ac-YLD, Ac-MYD, Ac-VIE) were chosen for experimental validation in order to illustrate the self-association outcomes predicted by the three metrics. Self-association and electron microscopy studies revealed that Ac-LLE formed bead-like microstructures, Ac-LVE and Ac-YYD formed fibrillar aggregates, Ac-VIE and Ac-MYD formed hydrogels, and Ac-YLD crystallized under ambient conditions. An X-ray crystallographic study was carried out on a single crystal of Ac-YLD, which revealed that each molecule adopts a β-strand conformation that stack together to form parallel β-sheets. As an additional validation of the approach, the hydrogel-forming sequences of Ac-MYD and Ac-VIE were shuffled. The shuffled sequences were computationally predicted to have lower K*association values and were experimentally verified to not form hydrogels. This illustrates the robustness of the framework in predicting self-associating tripeptides. We expect that this enhanced multimeric de novo peptide design framework will find future application in creating novel self-associating peptides based on unnatural amino acids, and inhibitor peptides of detrimental self-aggregating biological proteins. PMID:25010703

The Impact of Personal Background and School Contextual Factors on Academic Competence and Mental Health Functioning across the Primary-Secondary School Transition

PubMed Central

Vaz, Sharmila; Parsons, Richard; Falkmer, Torbjörn; Passmore, Anne Elizabeth; Falkmer, Marita

2014-01-01

Students negotiate the transition to secondary school in different ways. While some thrive on the opportunity, others are challenged. A prospective longitudinal design was used to determine the contribution of personal background and school contextual factors on academic competence (AC) and mental health functioning (MHF) of 266 students, 6-months before and after the transition to secondary school. Data from 197 typically developing students and 69 students with a disability were analysed using hierarchical linear regression modelling. Both in primary and secondary school, students with a disability and from socially disadvantaged backgrounds gained poorer scores for AC and MHF than their typically developing and more affluent counterparts. Students who attended independent and mid-range sized primary schools had the highest concurrent AC. Those from independent primary schools had the lowest MHF. The primary school organisational model significantly influenced post-transition AC scores; with students from Kindergarten - Year 7 schools reporting the lowest scores, while those from the Kindergarten - Year 12 structure without middle school having the highest scores. Attending a school which used the Kindergarten - Year 12 with middle school structure was associated with a reduction in AC scores across the transition. Personal background factors accounted for the majority of the variability in post-transition AC and MHF. The contribution of school contextual factors was relatively minor. There is a potential opportunity for schools to provide support to disadvantaged students before the transition to secondary school, as they continue to be at a disadvantage after the transition. PMID:24608366

The impact of personal background and school contextual factors on academic competence and mental health functioning across the primary-secondary school transition.

PubMed

Vaz, Sharmila; Parsons, Richard; Falkmer, Torbjörn; Passmore, Anne Elizabeth; Falkmer, Marita

2014-01-01

Students negotiate the transition to secondary school in different ways. While some thrive on the opportunity, others are challenged. A prospective longitudinal design was used to determine the contribution of personal background and school contextual factors on academic competence (AC) and mental health functioning (MHF) of 266 students, 6-months before and after the transition to secondary school. Data from 197 typically developing students and 69 students with a disability were analysed using hierarchical linear regression modelling. Both in primary and secondary school, students with a disability and from socially disadvantaged backgrounds gained poorer scores for AC and MHF than their typically developing and more affluent counterparts. Students who attended independent and mid-range sized primary schools had the highest concurrent AC. Those from independent primary schools had the lowest MHF. The primary school organisational model significantly influenced post-transition AC scores; with students from Kindergarten--Year 7 schools reporting the lowest scores, while those from the Kindergarten--Year 12 structure without middle school having the highest scores. Attending a school which used the Kindergarten--Year 12 with middle school structure was associated with a reduction in AC scores across the transition. Personal background factors accounted for the majority of the variability in post-transition AC and MHF. The contribution of school contextual factors was relatively minor. There is a potential opportunity for schools to provide support to disadvantaged students before the transition to secondary school, as they continue to be at a disadvantage after the transition.

Comparison of cadmium hydroxide nanowires and silver nanoparticles loaded on activated carbon as new adsorbents for efficient removal of Sunset yellow: Kinetics and equilibrium study.

PubMed

Ghaedi, Mehrorang

2012-08-01

Adsorption of Sunset yellow (SY) onto cadmium hydroxide nanowires loaded on activated carbon (Cd(OH)(2)-NW-AC) and silver nanoparticles loaded on activated carbon (Ag-NP-AC) was investigated. The effects of pH, contact time, amount of adsorbents, initial dye concentration, agitation speed and temperature on Sunset yellow removal on both adsorbents were studied. Following the optimization of variables, the experimental data were fitted to different conventional isotherm models like Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich (D-R) based on linear regression coefficient R(2) the Langmuir isotherm was found to be the best fitting isotherm model and the maximum monolayer adsorption capacities calculated based on this model for Cd(OH)(2)-NW-AC and Ag-NP-AC were found to be 76.9 and 37.03mg g(-1) at room temperatures, respectively. The experimental fitting of time dependency of adsorption of SY onto both adsorbent shows the applicability of second order kinetic model for interpretation of kinetic data. The pseudo-second order model best fits the adsorption kinetics. Thermodynamic parameters such as enthalpy, entropy, activation energy, sticking probability, and Gibb's free energy changes were also calculated. It was found that the sorption of SY over (Cd(OH)(2)-NW-AC) and (Ag-NP-AC) was spontaneous and endothermic in nature. Efficiency of the adsorbent was also investigated using real effluents and more than 95% SY removal for both adsorbents was observed. Copyright © 2012 Elsevier B.V. All rights reserved.

Optimizing a positive psychology intervention to promote health behaviors following an acute coronary syndrome: The Positive Emotions after Acute Coronary Events-III (PEACE-III) randomized factorial trial.

PubMed

Celano, Christopher M; Albanese, Ariana M; Millstein, Rachel A; Mastromauro, Carol A; Chung, Wei-Jean; Campbell, Kirsti A; Legler, Sean R; Park, Elyse R; Healy, Brian C; Collins, Linda M; Januzzi, James L; Huffman, Jeff C

2018-04-05

Despite the clear benefits of physical activity and related behaviors on prognosis, most patients suffering an acute coronary syndrome (ACS) remain nonadherent to these behaviors. Deficits in positive psychological constructs (e.g., optimism) are linked to reduced participation in health behaviors, supporting the potential utility of a positive psychology (PP)-based intervention in post-ACS patients. Accordingly, we aimed to identify optimal components of a PP-based intervention to promote post-ACS physical activity. As part of a multiphase optimization strategy, we completed a randomized factorial trial with eight conditions in 128 post-ACS patients to efficiently identify best-performing intervention components. All participants received a PP-based intervention, with conditions varying in duration (presence/absence of booster sessions), intensity (weekly/daily PP exercises), and content (PP alone or combined with motivational interviewing [MI]), allowing three concurrent comparisons within the trial. Study aims included assessments of the overall feasibility, acceptability, and impact of the intervention, along with the primary aim of determining which components were associated with objectively-measured physical activity and self-reported health behavior adherence at 16 weeks, assessed using longitudinal models. The intervention was well-accepted and associated with substantial improvements in behavioral and psychological outcomes. Booster sessions were associated with greater activity to a nearly significant degree (β=8.58, 95% confidence interval= -0.49-17.65, effect size difference=.43; p=.064), MI was associated with overall adherence (β=0.95, 95% confidence interval=0.02-1.87, effect size difference=.39; p=.044), and weekly exercise completion was generally superior to daily. These findings will enable optimization of the PP-based intervention in preparation for a well-powered controlled trial. ClinicalTrials.gov identifier: NCT02754895.

Two novel monoclonal antibodies against the MUC4 tandem repeat reacting with an antigen overexpressed by lung cancer.

PubMed

Botti, C; Seregni, E; Ménard, S; Collini, P; Tagliabue, E; Campiglio, M; Vergani, B; Ghirelli, C; Aiello, P; Pilotti, S; Bombardieri, E

2000-01-01

In this study we investigated the immunochemical and cytochemical reactivity of two monoclonal antibodies against the 16-amino acid tandem repeat of MUC4 to demonstrate a possible variation of the mucin core peptide expression related to lung cancer. The immunocytochemical anti-MUC4 reactivity was analyzed in four lung cancer cell lines (Calu-1, Calu-3, H460, SKMES) and in other tumor cell lines, as well as in frozen materials from 21 lung adenocarcinomas (ACs), including five bronchioloalveolar carcinomas (BACs), and 11 squamous cell lung carcinomas (SqCCs). A weak fluorescence anti-MUC4 positivity (range: 10.3-16.2) was observed only in acetone-fixed lung cancer cell lines Calu-1, Calu-3 and H460. These three lung cancer cell lines also showed a cytoplasmic immunoperoxidase reactivity. The immunostaining in lung cancer tissues showed a granular cytoplasmic reactivity: 15/21 (71%) and 17/21 (80%) ACs were positive with BC-LuC18.2 and BC-LuCF12, respectively. All BACs were positive. Moderate to strong reactivity was present in well-differentiated ACs. In the normal lung parenchyma counterparts weak reactivity was found only in bronchiolar cells. All SqCCs were negative. Anti-MUC4 reactivity was also observed in the alveolar mucus. In conclusion, our anti-MUC4 MAbs detect a secretion product present in mucus and this product is elaborated by lung cancer cells and overexpressed in well-differentiated lung ACs.

Major Depression and Acute Coronary Syndrome-Related Factors

PubMed Central

Figueiredo, Jose Henrique Cunha; Silva, Nelson Albuquerque de Souza e; Pereira, Basilio de Bragança; de Oliveira, Glaucia Maria Moraes

2017-01-01

Background Major Depressive Disorder (MDD) is one of the most common mental illnesses in psychiatry, being considered a risk factor for Acute Coronary Syndrome (ACS). Objective To assess the prevalence of MDD in ACS patients, as well as to analyze associated factors through the interdependence of sociodemographic, lifestyle and clinical variables. Methods Observational, descriptive, cross-sectional, case-series study conducted on patients hospitalized consecutively at the coronary units of three public hospitals in the city of Rio de Janeiro over a 24-month period. All participants answered a standardized questionnaire requesting sociodemographic, lifestyle and clinical data, as well as a structured diagnostic interview for the DSM-IV regarding ongoing major depressive episodes. A general log-linear model of multivariate analysis was employed to assess association and interdependence with a significance level of 5%. Results Analysis of 356 patients (229 men), with an average and median age of 60 years (SD ± 11.42, 27-89). We found an MDD point prevalence of 23%, and a significant association between MDD and gender, marital status, sedentary lifestyle, Killip classification, and MDD history. Controlling for gender, we found a statistically significant association between MDD and gender, age ≤ 60 years, sedentary lifestyle and MDD history. The log-linear model identified the variables MDD history, gender, sedentary lifestyle, and age ≤ 60 years as having the greatest association with MDD. Conclusion Distinct approaches are required to diagnose and treat MDD in young women with ACS, history of MDD, sedentary lifestyle, and who are not in stable relationships. PMID:28443957

MAP stability, design, and analysis

NASA Technical Reports Server (NTRS)

Ericsson-Jackson, A. J.; Andrews, S. F.; O'Donnell, J. R., Jr.; Markley, F. L.

1998-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE) spacecraft. The design and analysis of the MAP attitude control system (ACS) have been refined since work previously reported. The full spacecraft and instrument flexible model was developed in NASTRAN, and the resulting flexible modes were plotted and reduced with the Modal Significance Analysis Package (MSAP). The reduced-order model was used to perform the linear stability analysis for each control mode, the results of which are presented in this paper. Although MAP is going to a relatively disturbance-free Lissajous orbit around the Earth-Sun L(2) Lagrange point, a detailed disturbance-torque analysis is required because there are only a small number of opportunities for momentum unloading each year. Environmental torques, including solar pressure at L(2), aerodynamic and gravity gradient during phasing-loop orbits, were calculated and simulated. Thruster plume impingement torques that could affect the performance of the thruster modes were estimated and simulated, and a simple model of fuel slosh was derived to model its effect on the motion of the spacecraft. In addition, a thruster mode linear impulse controller was developed to meet the accuracy requirements of the phasing loop burns. A dynamic attitude error limiter was added to improve the performance of the ACS during large attitude slews. The result of this analysis is a stable ACS subsystem that meets all of the mission's requirements.

A Mixed-Integer Linear Programming Problem which is Efficiently Solvable.

DTIC Science & Technology

1987-10-01

INTEGER LINEAR PROGRAMMING PROBLEM WHICH IS EFFICIENTLY SOLVABLE 12. PERSONAL AUTHOR(S) Leiserson, Charles, and Saxe, James B. 13a. TYPE OF REPORT j13b TIME...ger prongramn rg versions or the problem is not ac’hievable in genieral for sparse inistancves of’ P rolem(r Mi. Th le remrai nder or thris paper is...rClazes c:oIh edge (i,I*) by comlpli urg +- rnirr(z 3, ,x + a,j). A sirnI) le analysis (11 vto Nei [131 indicates why whe Iellinan-Ford algorithm works

Computational Methods for Design, Estimation and Real-Time Control of PDE Systems with Applications to Mobile Sensor Networks

DTIC Science & Technology

2013-08-14

TIME CONTROL OF PDE SYSTEMS WITH APPLICATIONS TO MOBILE SENSOR NETWORKS Finall Report: AFOSR Grant...linear time invariant (LTI) control problem. If the control is a linear function of the states, then the closed loop system then takes the form[ żr u̇...Ar2 A r 3 0T 0 ] − [ Br 1 ] K ) ︸ ︷︷ ︸ Ac [ zr u ] . (3) As the purpose of the control law is to stabilize the system , it is desired to have

Internal friction and dislocation collective pinning in disordered quenched solid solutions

NASA Astrophysics Data System (ADS)

D'Anna, G.; Benoit, W.; Vinokur, V. M.

1997-12-01

We introduce the collective pinning of dislocations in disordered quenched solid solutions and calculate the macroscopic mechanical response to a small dc or ac applied stress. This work is a generalization of the Granato-Lücke string model, able to describe self-consistently short and long range dislocation motion. Under dc applied stress the long distance dislocation creep has at the microscopic level avalanche features, which result in a macroscopic nonlinear "glassy" velocity-stress characteristic. Under ac conditions the model predicts, in addition to the anelastic internal friction relaxation in the high frequency regime, a linear internal friction background which remains amplitude-independent down to a crossover frequency to a strongly nonlinear internal friction regime.

Trichopeptides A and B, trichocyclodipeptides A-C, new peptides from the ascomycete fungus Stagonospora trichophoricola.

PubMed

Chen, Zhengkun; Xu, Xiuli; Ren, Jinwei; Wang, Wenzhao; Liu, Xingzhong; Li, Erwei

2017-08-01

Trichopeptides A (1) and B (2), new linear tetrapeptide and tripeptide, respectively, and three new diketopiperazines trichocyclodipeptides A-C (3-5) were isolated from the fermentation of the ascomycete fungus Stagonospora trichophoricola, a fungus isolated from the soil sample surrounding the fruiting body of Ophiocordyceps sinensis in Maqin Country, Qinghai Province, People's Republic of China. Their structures were primarily elucidated by interpretation of NMR and MS experiments. The absolute configurations of 1-5 were assigned through Marfey's method on their acid hydrolyzates. Compound 3 showed antifungal activity against Candida albicans with the IC 50 and MIC values of 22 and 90 μg ml -1 , respectively.

Superconductivity in the graphene monolayer calculated using the Kubo formulalism

NASA Astrophysics Data System (ADS)

Lima, L. S.

2018-03-01

We have employed the massless Dirac's fermions formalism together with the Kubo's linear response theory to study the transport by electrons in the graphene monolayer. We have calculated the electric conductivity and verified the behavior of the AC and DC electric conductivities of the system that is known to be a relativistic electron plasma. Our results show a superconductor behavior to the electron transport and consequently the spin transport for all values of T > 0 and a behavior of the AC conductivity tending to infinity in the limit ω → 0. In T = 0 our results show an insulator behavior with a transition from a superconductor state at T > 0 to an insulator state at T = 0 .

A new venous infusion path monitoring system utilizing electrostatic induced potential.

PubMed

Ogawa, Hidekuni; Yonezawa, Yoshiharu; Maki, Hiromichi; Caldwell, W Morton

2008-01-01

A new venous infusion pathway monitoring system has been developed for hospital and home use. The system consists of linear and digital integrated circuits and a low-power 8-bit single chip microcomputer which constantly monitors the infusion pathway intactness. A 330 kHz AC voltage, which is induced on the patient's body by electrostatic coupling from a 330 kHz pulse oscillator, can be recorded by main and reference electrodes wrapped around the infusion polyvinyl chloride tube. If the injection needle or infusion tube becomes detached, then the system detects changes in the induced AC voltages and alerts the nursing station, via the nurse call system or PHS (personal handy phone system).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baker, Kyri; Dall'Anese, Emiliano; Summers, Tyler

This paper outlines a data-driven, distributionally robust approach to solve chance-constrained AC optimal power flow problems in distribution networks. Uncertain forecasts for loads and power generated by photovoltaic (PV) systems are considered, with the goal of minimizing PV curtailment while meeting power flow and voltage regulation constraints. A data- driven approach is utilized to develop a distributionally robust conservative convex approximation of the chance-constraints; particularly, the mean and covariance matrix of the forecast errors are updated online, and leveraged to enforce voltage regulation with predetermined probability via Chebyshev-based bounds. By combining an accurate linear approximation of the AC power flowmore » equations with the distributionally robust chance constraint reformulation, the resulting optimization problem becomes convex and computationally tractable.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yijian; Hong, Mingyi; Dall'Anese, Emiliano

This paper considers power distribution systems featuring renewable energy sources (RESs), and develops a distributed optimization method to steer the RES output powers to solutions of AC optimal power flow (OPF) problems. The design of the proposed method leverages suitable linear approximations of the AC-power flow equations, and is based on the Alternating Direction Method of Multipliers (ADMM). Convergence of the RES-inverter output powers to solutions of the OPF problem is established under suitable conditions on the stepsize as well as mismatches between the commanded setpoints and actual RES output powers. In a broad sense, the methods and results proposedmore » here are also applicable to other distributed optimization problem setups with ADMM and inexact dual updates.« less

Actinium-225 in targeted alpha-particle therapeutic applications

PubMed Central

Scheinberg, David A.; McDevit, Michael R.

2017-01-01

Alpha particle-emitting isotopes are being investigated in radioimmunotherapeutic applications because of their unparalleled cytotoxicity when targeted to cancer and their relative lack of toxicity towards untargeted normal tissue. Actinium-225 has been developed into potent targeting drug constructs and is in clinical use against acute myelogenous leukemia. The key properties of the alpha particles generated by 225Ac are the following: i) limited range in tissue of a few cell diameters; ii) high linear energy transfer leading to dense radiation damage along each alpha track; iii) a 10 day half-life; and iv) four net alpha particles emitted per decay. Targeting 225Ac-drug constructs have potential in the treatment of cancer. PMID:22202153

Matrix Converter Interface for a Wind Energy Conversion System: Issues and Limitations

NASA Astrophysics Data System (ADS)

Patki, Chetan; Agarwal, Vivek

2009-08-01

Variable speed grid connected wind energy systems sometimes involve AC-AC power electronic interface between the generator and the grid. Matrix converter is an attractive option for such applications. Variable speed of the wind generator demands variable voltage variable frequency at the generator terminal. Matrix converter is used in this work to generate such a supply. Also, matrix converter can be appropriately controlled to compensate the grid for non-linear, reactive loads. However, any change of power factor on the grid side reflects on the voltage magnitude on the wind generator side. It is highlighted that this may contradict the maximum power point tracking control requirements. All the results of this work are presented.

Aedes communis Reactivity Is Associated with Bee Venom Hypersensitivity: An in vitro and in vivo Study.

PubMed

Scala, Enrico; Pirrotta, Lia; Uasuf, Carina G; Mistrello, Gianni; Amato, Stefano; Guerra, Emma Cristina; Locanto, Maria; Meneguzzi, Giorgia; Giani, Mauro; Cecchi, Lorenzo; Abeni, Damiano; Asero, Riccardo

2018-01-01

Mosquito bite is usually followed by a local reaction, but severe or systemic reaction may, in rare cases, occur. Allergic reactions to Aedes communis (Ac) may be underestimated due to the lack of reliable diagnostic tools. In this multicenter study, 205 individuals reporting large local reactions to Ac were enrolled and studied for cutaneous or IgE reactivity to Ac, Blattella germanica, Penaeus monodon, and Dermatophagoides pteronyssinus. Extract and molecular IgE reactivity to bees, wasps, hornets, and yellow jacket venoms were also studied in 119 patients with a clinical history of adverse reaction to Hymenoptera. Immunoblot (IB) analysis and immunoCAP IgE inhibition experiments were carried out in selected sera. Ac sensitization was recorded in 96 (46.8%) patients on SPT. Strict relationship between Ac and D. pteronyssinus, B. germanica, P. monodon, or Apis mellifera reactivity on SPT was observed. Ac IgE recognition was seen in 60/131 (45.8%) patients, 49 (81.6%) of them SPT positive, and 5/14 IB reactors. Ac IgE sensitization was associated with Tabanus spp, A. mellifera, Vespula vulgaris, and Polistes dominula reactivity. A strict relationship between Ac IgE reactivity and Api m 1, Api m 2, Api m 3, Api m 5, and Api m 10 was recorded. IgE reactivity to AC was inhibited in 9/15 cases after serum absorption with the A. mellifera extract. Both SPT and IgE Ac reactivity is observed in about half of patients with a history of large local reactions to mosquito bites. The significant relationship between Ac sensitization and either extract or single bee venom components is suggestive of a "bee-mosquito syndrome" occurrence. © 2018 S. Karger AG, Basel.

[Analysis of AC/A ratio after myopic excimer laser in situ keratomileusis].

PubMed

Wu, Xiao-ying; Liu, Shuang-zhen

2003-03-01

To study the changes of AC/A ratio of myopia after excimer laser in situ keratomileusis (LASIK). 135 myopia patients were treated by LASIK, their AC/A ratios were measured with synoptohore before surgery and 3 months after surgery. The average AC/A ratios of naked eyes or eyes wearing glasses before surgery and the naked after surgery were (0.724 +/- 0.587) (Delta)/D, (2.754 +/- 1.565) (Delta)/D, (1.618 +/- 1.027) (Delta)/D in turn. There were significant difference among those groups (P < 0.001). That also appeared in different degree of myopia naked before surgery (P < 0.01). We found no significant difference between the groups wearing glasses before surgery and naked after surgery (P > 0.05). A positive correlation was built up between postoperative AC/A ratio and AC/A ratio of wearing glasses or refractive diopter before surgery (r = 0.550, P < 0.001; r = 0.185, P < 0.005). And the postoperative AC/A ratios had a negative correlation to age or length of ocular axis (r = -0.340, P < 0.001; r = -0.192, P < 0.002). The regression equation for postoperative AC/A ratios was figured out as Y((Delta)/D) = 4.080 0 - 0.031 8X(1) - 0.097 1X(2) + 0.325 0X(3) (P < 0.001). X(1) = age (year), X(2) = length of ocular axis (mm), X(3) = preoperative AC/A ratio with weaning glasses ((Delta)/D). The naked AC/A ratios are higher than the preoperative's after LASIK, but lower than the wearing glasses's before surgery. It is influenced by the factors, such as: the preoperative AC/A ratio of wearing glasses, the length of ocular axis and the age.

Adsorptive Removal of Nitrate from Aqueous Solution Using Nitrogen Doped Activated Carbon.

PubMed

Machida, Motoi; Goto, Tatsuru; Amano, Yoshimasa; Iida, Tatsuya

2016-01-01

Activated carbon (AC) has been widely applied for adsorptive removal of organic contaminants from aqueous phase, but not for ionic pollutants. In this study, nitrogen doped AC was prepared to increase the adsorption capacity of nitrate from water. AC was oxidized with (NH 4 ) 2 S 2 O 8 solution to maximize oxygen content for the first step, and then NH 3 gas treatment was carried out at 950°C to aim at forming quaternary nitrogen (N-Q) species on AC surface (Ox-9.5AG). Influence of solution pH was examined so as to elucidate the relationship between surface charge and adsorption amounts of nitrate. The results showed that Ox-9.5AG exhibited about twice higher adsorption capacity than non-treatment AC at any initial nitrate concentration and any equilibrium solution pH (pH e ) investigated. The more decrease in pH e value, the more adsorption amount of negatively charged nitrate ion, because the surface charge of AC and Ox-9.5AG could become more positive in acidic solution. The oxidation and consecutive ammonia treatments lead to increase in nitrogen content from 0.35 to 6.4% and decrease in the pH of the point of zero charge (pH pzc ) from 7.1 to 4.0 implying that positively charged N-Q of a Lewis acid was created on the surface of Ox-9.5AG. Based on a Langmuir data analysis, maximum adsorption capacity attained 0.5-0.6 mmol/g of nitrate and adsorption affinity was 3.5-4.0 L/mmol at pH e 2.5 for Ox-9.5AG.

Interleukin-13-induced MUC5AC expression is regulated by a PI3K–NFAT3 pathway in mouse tracheal epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Fugui; Li, Wen; Zhou, Hongbin

Highlights: • IL-13 specifically induced NFAT3 activation in mouse tracheal epithelial cells. • CsA and LY294002 significantly blocked IL-13-induced MUC5AC production. • The PI3K–NFAT3 pathway is positively involved in IL-13-induced MUC5AC production. - Abstract: Interleukin-13 (IL-13) plays a critical role in asthma mucus overproduction, while the mechanisms underlying this process are not fully elucidated. Previous studies showed that nuclear factor of activated T cells (NFAT) is involved in the pathogenesis of asthma, but whether it can directly regulate IL-13-induced mucus (particularly MUC5AC) production is still not clear. Here we showed that IL-13 specifically induced NFAT3 activation through promoting its dephosphorylationmore » in air–liquid interface (ALI) cultures of mouse tracheal epithelial cells (mTECs). Furthermore, both Cyclosporin A (CsA, a specific NFAT inhibitor) and LY294002 (a Phosphoinositide 3-kinase (PI3K) inhibitor) significantly blocked IL-13-induced MUC5AC mRNA and protein production through the inhibition of NFAT3 activity. We also confirmed that CsA could not influence the forkhead Box A2 (Foxa2) and mouse calcium dependent chloride channel 3 (mClca3) expression in IL-13-induced MUC5AC production, which both are known to be important in IL-13-stimulated mucus expression. Our study is the first to demonstrate that the PI3K–NFAT3 pathway is positively involved in IL-13-induced mucus production, and provided novel insights into the molecular mechanism of asthma mucus hypersecretion.« less

STAT3:FOXM1 and MCT1 drive uterine cervix carcinoma fitness to a lactate-rich microenvironment.

PubMed

Silva, Lidia Santos; Goncalves, Luis Gafeira; Silva, Fernanda; Domingues, Germana; Maximo, Valdemar; Ferreira, Joana; Lam, Eric W-F; Dias, Sergio; Felix, Ana; Serpa, Jacinta

2016-04-01

Uterine cervix cancer is the second most common malignancy in women worldwide with human papillomavirus (HPV) as the etiologic factor. The two main histological variants, squamous cell carcinomas (SCC) and adenocarcinomas (AC), resemble the cell morphology of exocervix and endocervix, respectively. Cancer metabolism is a cancer hallmark conditioned by the microenvironment. As uterine cervix homeostasis is dependent on lactate, we hypothesized lactate plays a role in uterine cervix cancer progression. Using in vitro (SiHa-SCC and HeLa-AC) and BALB-c/SCID models, we demonstrated that lactate metabolism is linked to histological types, with SCC predominantly consuming and AC producing lactate. MCT1 is a key factor, allowing lactate consumption and being regulated in vitro by lactate through the FOXM1:STAT3 pathway. In vivo models showed that SCC (SiHa) expresses MCT1 and is dependent on lactate to grow, whereas AC (HeLa) expresses MCT1 and MCT4, with higher growth capacities. Immunohistochemical analysis of tissue microarrays (TMA) from human cervical tumors showed that MCT1 expression associates with the SCC type and metastatic behavior of AC, whereas MCT4 expression concomitantly increases from in situ SCC to invasive SCC and is significantly associated with the AC type. Consistently, FOXM1 expression is statistically associated with MCT1 positivity in SCC, whereas the expression of FOXO3a, a FOXM1 functional antagonist, is linked to MCT1 negativity in AC. Our study reinforces the role of the microenvironment in the metabolic adaptation of cancer cells, showing that cells that retain metabolic features of their normal counterparts are positively selected by the organ's microenvironment and will survive. In particular, MCT1 was shown to be a key element in uterine cervix cancer development; however, further studies are needed to validate MCT1 as a suitable therapeutic target in uterine cervix cancer.

An extreme Arctic cyclone in August 2016 and its predictability on medium-range timescales

NASA Astrophysics Data System (ADS)

Yamagami, Akio; Matsueda, Mio; Tanaka, Hiroshi

2017-04-01

An extremely strong Arctic cyclone (AC) developed in August 2016. The AC exhibited a minimum sea level pressure (SLP) of 967.2 hPa and covered the entire Pacific sector of the Arctic Ocean at 0000UTC on 16 August. At this time the AC was comparable to the strong AC observed in August 2012, in terms of horizontal extent, position, and intensity as measured by SLP. Two processes contributed to the explosive development of the AC: growth due to baroclinic instability, similar to extratropical cyclones, during the early part of the development stage, and later nonlinear development via the merging of upper warm cores. The AC was maintained for more than one month through multiple mergings with cyclones both generated in the Arctic and migrating northward from lower latitudes, as a result of the high cyclone activity in summer 2016. This study also investigated the predictability of the AC using operational medium-range ensemble forecasts: CMC (Canada), ECMWF (EU), JMA (Japan), NCEP (USA), and UKMO (UK), available at the The Interactive Grand Global Ensemble (TIGGE) database. The minimum SLP of the AC at 0000UTC on 16 August was well predicted by ECMWF 6-day, NCEP and UKMO 5-day, CMC 4-day, and JMA 3-day in advance. The predictability of the minimum SLP of the AC in August 2016 was much higher than that of the AC in 2012 August. Whereas most of the members well predicted the cyclogenesis of the AC, the growth due to baroclinic instability was weaker in some members. Even if the baroclinic growth was predicted well, predicted AC did not develop when the nonlinear development via the merging was not predict accurately. The accurate prediction of the processes in both early and later parts of the development stage was important for the accurate prediction of the development of the AC.

Transdifferentiation of mouse adipose-derived stromal cells into acinar cells of the submandibular gland using a co-culture system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Jingu; Park, Sangkyu; Roh, Sangho, E-mail: sangho@snu.ac.kr

A loss of salivary gland function often occurs after radiation therapy in head and neck tumors, though secretion of saliva by the salivary glands is essential for the health and maintenance of the oral environment. Transplantation of salivary acinar cells (ACs), in part, may overcome the side effects of therapy. Here we directly differentiated mouse adipose-derived stromal cells (ADSCs) into ACs using a co-culture system. Multipotent ADSCs can be easily collected from stromal vascular fractions of adipose tissues. The isolated ADSCs showed positive expression of markers such as integrin beta-1 (CD29), cell surface glycoprotein (CD44), endoglin (CD105), and Nanog. Themore » cells were able to differentiate into adipocytes, osteoblasts, and neural-like cells after 14 days in culture. ADSCs at passage 2 were co-cultured with mouse ACs in AC culture medium using the double-chamber (co-culture system) to avoid mixing the cell types. The ADSCs in this co-culture system expressed markers of ACs, such as α-amylases and aquaporin5, in both mRNA and protein. ADSCs cultured in AC-conditioned medium also expressed AC markers. Cellular proliferation and senescence analyses demonstrated that cells in the co-culture group showed lower senescence and a higher proliferation rate than the AC-conditioned medium group at Days 14 and 21. The results above imply direct conversion of ADSCs into ACs under the co-culture system; therefore, ADSCs may be a stem cell source for the therapy for salivary gland damage. - Highlights: • ADSCs could transdifferentiate into acinar cells (ACs) using ACs co-culture (CCA). • Transdifferentiated ADSCs expressed ACs markers such as α-amylase and aquaporin5. • High proliferation and low senescence were presented in CCA at Day 14. • Transdifferentiation of ADSCs into ACs using CCA may be an appropriate method for cell-based therapy.« less

Deformation of giant vesicles in AC electric fields —Dependence of the prolate-to-oblate transition frequency on vesicle radius

NASA Astrophysics Data System (ADS)

Antonova, K.; Vitkova, V.; Mitov, M. D.

2010-02-01

The electrodeformation of giant vesicles is studied as a function of their radii and the frequency of the applied AC field. At low frequency the shape is prolate, at sufficiently high frequency it is oblate and at some frequency, fc, the shape changes from prolate to oblate. A linear dependence of the prolate-to-oblate transition inverse frequency, 1/fc, on the vesicle radius is found. The nature of this phenomenon does not change with the variation of both the solution conductivity, σ, and the type of the fluid enclosed by the lipid membrane (water, sucrose or glucose aqueous solution). When σ increases, the value of fc increases while the slope of the line 1/fc(r) decreases. For vesicles in symmetrical conditions (the same conductivity of the inner and the outer solution) a linear dependence between σ and the critical frequency, fc, is obtained for conductivities up to σ=114 μS/cm. For vesicles with sizes below a certain minimum radius, depending on the solution conductivity, no shape transition could be observed.

Blind Deconvolution for Distributed Parameter Systems with Unbounded Input and Output and Determining Blood Alcohol Concentration from Transdermal Biosensor Data.

PubMed

Rosen, I G; Luczak, Susan E; Weiss, Jordan

2014-03-15

We develop a blind deconvolution scheme for input-output systems described by distributed parameter systems with boundary input and output. An abstract functional analytic theory based on results for the linear quadratic control of infinite dimensional systems with unbounded input and output operators is presented. The blind deconvolution problem is then reformulated as a series of constrained linear and nonlinear optimization problems involving infinite dimensional dynamical systems. A finite dimensional approximation and convergence theory is developed. The theory is applied to the problem of estimating blood or breath alcohol concentration (respectively, BAC or BrAC) from biosensor-measured transdermal alcohol concentration (TAC) in the field. A distributed parameter model with boundary input and output is proposed for the transdermal transport of ethanol from the blood through the skin to the sensor. The problem of estimating BAC or BrAC from the TAC data is formulated as a blind deconvolution problem. A scheme to identify distinct drinking episodes in TAC data based on a Hodrick Prescott filter is discussed. Numerical results involving actual patient data are presented.

Dependency of Tearing Mode Stability on Current and Pressure Profiles in DIII-D Hybrid Discharges

NASA Astrophysics Data System (ADS)

Kim, K.; Park, J. M.; Murakami, M.; La Haye, R. J.; Na, Y.-S.; SNU/ORAU; ORNL; Atomics, General; SNU; DIII-D Team

2016-10-01

Understanding the physics of the onset and evolution of tearing modes (TMs) in tokamak plasmas is important for high- β steady-state operation. Based on DIII-D steady-state hybrid experiments with accurate equilibrium reconstruction and well-measured plasma profiles, the 2/1 tearing mode can be more stable with increasing local current and pressure gradient at rational surface and with lower pressure peaking and plasma inductance. The tearing stability index Δ', estimated by the Rutherford equation with experimental mode growth rate was validated against Δ' calculated by linear eigenvalue solver (PEST3); preliminary comprehensive MHD modeling by NIMROD reproduced the TM onset reasonably well. We present a novel integrated modeling for the purpose of predicting TM onset in experiment by combining a model equilibrium reconstruction using IPS/FASTRAN, linear stability Δ' calculation using PEST3, and fitting formula for critical Δ' from NIMROD. Work supported in part by the US DoE under DE-AC05-06OR23100, DE-AC05-00OR22725, and DEFC02-04ER54698.

Absolute and relative kinetic changes of high-sensitivity cardiac troponin T in acute coronary syndrome and in patients with increased troponin in the absence of acute coronary syndrome.

PubMed

Mueller, Matthias; Biener, Moritz; Vafaie, Mehrshad; Doerr, Susanne; Keller, Till; Blankenberg, Stefan; Katus, Hugo A; Giannitsis, Evangelos

2012-01-01

We evaluated kinetic changes of high-sensitivity cardiac troponin T (hs-cTnT) in patients with acute coronary syndrome (ACS) and patients with hs-cTnT increases not due to ACS to rule in or rule out non-ST-segment elevation myocardial infarction (STEMI). hs-cTnT was measured serially in consecutive patients presenting to the emergency department. Patients with ACS who had at least 2 hs-cTnT measurements within 6 h and non-ACS patients with hs-cTnT concentrations above the 99th percentile value (14 ng/L) were enrolled to compare absolute and relative kinetic changes of hs-cTnT. For discrimination of non-STEMI (n=165) in the entire study population (n=784), the absolute δ change with the ROC-optimized value of 9.2 ng/L yielded an area under the curve of 0.898 and was superior to all relative δ changes (P<0.0001). The positive predictive value for the absolute δ change was 48.7%, whereas the negative predictive value was 96.5%. In a specific ACS population with exclusion of STEMI (n=342), the absolute δ change with the ROC-optimized value of 6.9 ng/L yielded a positive predictive value of 82.8% and a negative predictive value of 93.0%. In comparison to the ≥20% relative δ change, the ROC-optimized absolute δ change demonstrated a significantly added value for the entire study population and for the ACS cohort (net reclassification index 0.331 and 0.499, P<0.0001). Absolute δ changes appear superior to relative δ changes in discriminating non-STEMI. A rise or fall of at least 9.2 ng/L in the entire study population and 6.9 ng/L in selected ACS patients seems adequate to rule-out non-STEMI. However, δ-values are useful to rule-in non-STEMI only in a specific ACS population.

Design of Distributed Controllers Seeking Optimal Power Flow Solutions Under Communication Constraints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall'Anese, Emiliano; Simonetto, Andrea; Dhople, Sairaj

This paper focuses on power distribution networks featuring inverter-interfaced distributed energy resources (DERs), and develops feedback controllers that drive the DER output powers to solutions of time-varying AC optimal power flow (OPF) problems. Control synthesis is grounded on primal-dual-type methods for regularized Lagrangian functions, as well as linear approximations of the AC power-flow equations. Convergence and OPF-solution-tracking capabilities are established while acknowledging: i) communication-packet losses, and ii) partial updates of control signals. The latter case is particularly relevant since it enables asynchronous operation of the controllers where DER setpoints are updated at a fast time scale based on local voltagemore » measurements, and information on the network state is utilized if and when available, based on communication constraints. As an application, the paper considers distribution systems with high photovoltaic integration, and demonstrates that the proposed framework provides fast voltage-regulation capabilities, while enabling the near real-time pursuit of solutions of AC OPF problems.« less

Design of Distributed Controllers Seeking Optimal Power Flow Solutions under Communication Constraints: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall'Anese, Emiliano; Simonetto, Andrea; Dhople, Sairaj

This paper focuses on power distribution networks featuring inverter-interfaced distributed energy resources (DERs), and develops feedback controllers that drive the DER output powers to solutions of time-varying AC optimal power flow (OPF) problems. Control synthesis is grounded on primal-dual-type methods for regularized Lagrangian functions, as well as linear approximations of the AC power-flow equations. Convergence and OPF-solution-tracking capabilities are established while acknowledging: i) communication-packet losses, and ii) partial updates of control signals. The latter case is particularly relevant since it enables asynchronous operation of the controllers where DER setpoints are updated at a fast time scale based on local voltagemore » measurements, and information on the network state is utilized if and when available, based on communication constraints. As an application, the paper considers distribution systems with high photovoltaic integration, and demonstrates that the proposed framework provides fast voltage-regulation capabilities, while enabling the near real-time pursuit of solutions of AC OPF problems.« less

Performance characteristics of nanocrystalline diamond vacuum field emission transistor array

NASA Astrophysics Data System (ADS)

Hsu, S. H.; Kang, W. P.; Davidson, J. L.; Huang, J. H.; Kerns, D. V.

2012-06-01

Nitrogen-incorporated nanocrystalline diamond (ND) vacuum field emission transistor (VFET) with self-aligned gate is fabricated by mold transfer microfabrication technique in conjunction with chemical vapor deposition (CVD) of nanocrystalline diamond on emitter cavity patterned on silicon-on-insulator (SOI) substrate. The fabricated ND-VFET demonstrates gate-controlled emission current with good signal amplification characteristics. The dc characteristics of the ND-VFET show well-defined cutoff, linear, and saturation regions with low gate turn-on voltage, high anode current, negligible gate intercepted current, and large dc voltage gain. The ac performance of the ND-VFET is measured, and the experimental data are analyzed using a modified small signal circuit model. The experimental results obtained for the ac voltage gain are found to agree with the theoretical model. A higher ac voltage gain is attainable by using a better test setup to eliminate the associated parasitic capacitances. The paper reveals the amplifier characteristics of the ND-VFET for potential applications in vacuum microelectronics.

Performance characteristics of nanocrystalline diamond vacuum field emission transistor array

NASA Astrophysics Data System (ADS)

Hsu, S. H.; Kang, W. P.; Davidson, J. L.; Huang, J. H.; Kerns, D. V.

2012-05-01

Nitrogen-incorporated nanocrystalline diamond (ND) vacuum field emission transistor (VFET) with self-aligned gate is fabricated by mold transfer microfabrication technique in conjunction with chemical vapor deposition (CVD) of nanocrystalline diamond on emitter cavity patterned on silicon-on-insulator (SOI) substrate. The fabricated ND-VFET demonstrates gate-controlled emission current with good signal amplification characteristics. The dc characteristics of the ND-VFET show well-defined cutoff, linear, and saturation regions with low gate turn-on voltage, high anode current, negligible gate intercepted current, and large dc voltage gain. The ac performance of the ND-VFET is measured, and the experimental data are analyzed using a modified small signal circuit model. The experimental results obtained for the ac voltage gain are found to agree with the theoretical model. A higher ac voltage gain is attainable by using a better test setup to eliminate the associated parasitic capacitances. The paper reveals the amplifier characteristics of the ND-VFET for potential applications in vacuum microelectronics.

Circular Array of Magnetic Sensors for Current Measurement: Analysis for Error Caused by Position of Conductor.

PubMed

Yu, Hao; Qian, Zheng; Liu, Huayi; Qu, Jiaqi

2018-02-14

This paper analyzes the measurement error, caused by the position of the current-carrying conductor, of a circular array of magnetic sensors for current measurement. The circular array of magnetic sensors is an effective approach for AC or DC non-contact measurement, as it is low-cost, light-weight, has a large linear range, wide bandwidth, and low noise. Especially, it has been claimed that such structure has excellent reduction ability for errors caused by the position of the current-carrying conductor, crosstalk current interference, shape of the conduction cross-section, and the Earth's magnetic field. However, the positions of the current-carrying conductor-including un-centeredness and un-perpendicularity-have not been analyzed in detail until now. In this paper, for the purpose of having minimum measurement error, a theoretical analysis has been proposed based on vector inner and exterior product. In the presented mathematical model of relative error, the un-center offset distance, the un-perpendicular angle, the radius of the circle, and the number of magnetic sensors are expressed in one equation. The comparison of the relative error caused by the position of the current-carrying conductor between four and eight sensors is conducted. Tunnel magnetoresistance (TMR) sensors are used in the experimental prototype to verify the mathematical model. The analysis results can be the reference to design the details of the circular array of magnetic sensors for current measurement in practical situations.

Positioning activated carbon amendment technologies in a novel framework for sediment management.

PubMed

Kupryianchyk, Darya; Rakowska, Magdalena I; Reible, Danny; Harmsen, Joop; Cornelissen, Gerard; van Veggel, Marc; Hale, Sarah E; Grotenhuis, Tim; Koelmans, Albert A

2015-04-01

Contaminated sediments can pose serious threats to human health and the environment by acting as a source of toxic chemicals. The amendment of contaminated sediments with strong sorbents like activated C (AC) is a rapidly developing strategy to manage contaminated sediments. To date, a great deal of attention has been paid to the technical and ecological features and implications of sediment remediation with AC, although science in this field still is rapidly evolving. This article aims to provide an update on the recent literature on these features, and provides a comparison of sediment remediation with AC to other sediment management options, emphasizing their full-scale application. First, a qualitative overview of advantages of current alternatives to remediate contaminated sediments is presented. Subsequently, AC treatment technology is critically reviewed, including current understanding of the effectiveness and ecological safety for the use of AC in natural systems. Finally, this information is used to provide a novel framework for supporting decisions concerning sediment remediation and beneficial reuse. © 2015 SETAC.

Identification of Escherichia coli F4ac-binding proteins in porcine milk fat globule membrane

PubMed Central

Novakovic, Predrag; Huang, Yanyun Y.; Lockerbie, Betty; Shahriar, Farshid; Kelly, John; Gordon, John R.; Middleton, Dorothy M.; Loewen, Matthew E.; Kidney, Beverly A.; Simko, Elemir

2015-01-01

F4ac-positive enterotoxigenic Escherichia coli (ETEC) must attach to the intestinal mucosa to cause diarrhea in piglets. Prevention of bacterial attachment to the intestinal mucosa is the most effective defense against ETEC-induced diarrhea. Porcine milk fat globule membranes (MFGM) were shown to be able to inhibit attachment of ETEC to the intestinal brush border; however, the specific components of porcine MFGM that inhibited attachment of ETEC to enterocytes were not identified. Accordingly, the purpose of this study was to identify F4ac-binding MFGM proteins by overlay Western blot and affinity chromatography. The proteome of porcine MFGM was characterized and the following F4ac-binding proteins were detected by overlay Western blot and affinity chromatography: lactadherin, butyrophilin, adipophilin, acyl-CoA synthetase 3, and fatty acid-binding protein 3. The biological function of these proteins was not investigated but it is possible that their interaction with F4ac fimbria interferes with bacterial attachment and colonization. PMID:25852227

Cardiac patients' perceptions of neighboring patients' risk: influence on psychological stress in the ED and subsequent posttraumatic stress.

PubMed

Konrad, Beatrice; Hiti, David; Chang, Bernard P; Retuerto, Jessica; Julian, Jacob; Edmondson, Donald

2017-11-06

As many as 12% of acute coronary syndrome (ACS) patients screen positive for post-traumatic stress disorder (PTSD) symptoms due to their cardiac event, and emergency department (ED) factors such as overcrowding have been associated with risk for PTSD. We tested the association of patients' perceptions of their proximity to a critically ill patient during ED evaluation for ACS with development of posttraumatic stress symptoms (PSS) in the month after hospital discharge. Participants were enrolled in the REactions to Acute Care and Hospitalization (REACH) study during evaluation for ACS in an urban ED. Participants reported whether they perceived a patient near them was close to death. They also reported their current fear, concern they may die, perceived control, and feelings of vulnerability on an Emergency Room Perceptions questionnaire. One month later, participants reported on PTSD symptoms specific to the cardiac event and ED hospitalization. Of 763 participants, 12% reported perceiving a nearby patient was likely to die. In a multivariate linear regression model [F(9757) = 19.69, p < .001, R 2 adjusted = .18] with adjustment for age, sex, GRACE cardiac risk score, discharge ACS diagnosis, Charlson comorbidity index, objective ED crowding, and depression symptoms at baseline, perception of a nearby patients' likely death was associated with a 2.33 point (95% CI, 0.60-4.61) increase in 1 month PTSD score. A post hoc mediation analysis with personal threat perceptions [F(10,756) = 25.28, p < .001, R 2 adjusted = .24] showed increased personal threat perceptions during the ED visit, B = 0.71 points on the PCL per point on the personal threat perception questionnaire, β = 0.27, p = .001, fully mediated association of participants' perceptions of nearby patients' likely death with 1-month PTSD score (after adjustment for ED threat perceptions,) B = 0.89 (95% CI, -1.33 to 3.12), β = 0.03, p = .43, accounting for 62% of the adjusted effect and causing the main effect to become statistically nonsignificant. We found patients who perceived a nearby patient was likely to die had significantly greater PTSD symptoms at 1 month. Awareness of this association may be helpful for designing ED patient management procedures to identify and treat patients with an eye to post-ACS psychological care.

Towards improved hardware component attenuation correction in PET/MR hybrid imaging

NASA Astrophysics Data System (ADS)

Paulus, D. H.; Tellmann, L.; Quick, H. H.

2013-11-01

In positron emission tomography/computed tomography (PET/CT) hybrid imaging attenuation correction (AC) of the patient tissue and patient table is performed by converting the CT-based Hounsfield units (HU) to linear attenuation coefficients (LAC) of PET. When applied to the new field of hardware component AC in PET/magnetic resonance (MR) hybrid imaging, this conversion method may result in local overcorrection of PET activity values. The aim of this study thus was to optimize the conversion parameters for CT-based AC of hardware components in PET/MR. Systematic evaluation and optimization of the HU to LAC conversion parameters has been performed for the hardware component attenuation map (µ-map) of a flexible radiofrequency (RF) coil used in PET/MR imaging. Furthermore, spatial misregistration of this RF coil to its µ-map was simulated by shifting the µ-map in different directions and the effect on PET quantification was evaluated. Measurements of a PET NEMA standard emission phantom were performed on an integrated hybrid PET/MR system. Various CT parameters were used to calculate different µ-maps for the flexible RF coil and to evaluate the impact on the PET activity concentration. A 511 keV transmission scan of the local RF coil was used as standard of reference to adapt the slope of the conversion from HUs to LACs at 511 keV. The average underestimation of the PET activity concentration due to the non-attenuation corrected RF coil in place was calculated to be 5.0% in the overall phantom. When considering attenuation only in the upper volume of the phantom, the average difference to the reference scan without RF coil is 11.0%. When the PET/CT conversion is applied, an average overestimation of 3.1% (without extended CT scale) and 4.2% (with extended CT scale) is observed in the top volume of the NEMA phantom. Using the adapted conversion resulting from this study, the deviation in the top volume of the phantom is reduced to -0.5% and shows the lowest standard deviation inside the phantom in comparison to all other conversions. Simulation of a µ-map misregistration shows acceptable results for shifts below 5 mm for the flexible surface RF coil. The adapted conversion from HUs to LAC at 511 keV within this study can improve hardware component AC in PET/MR hybrid imaging as shown for a flexible RF surface coil. Furthermore, these results have a direct impact on the improvement of the hardware component AC of the examined flexible RF coil in conjunction with position determination.

Cytokine profile and proviral load among Japanese immigrants and non-Japanese infected with HTLV-1 in a non-endemic area of Brazil.

PubMed

Domingos, João Américo; Soares, Luana Silva; Bandeira, Larissa M; Bonin, Camila Mareti; Vicente, Ana C P; Zanella, Louise; Puga, Marco Antonio Moreira; Tozetti, Inês Aparecida; Motta-Castro, Ana Rita Coimbra; da Cunha, Rivaldo Venâncio

2017-01-01

The lifetime risk of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) development differs among ethnic groups. To better understand these differences, this prospective cohort study was conducted to investigate the cytokine profile and the HTLV-1 proviral load (PVL) in Japanese and non-Japanese populations with HAM/TSP and asymptomatic carriers (ACs). The serum IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α, and IFN-γ levels were quantified using the Cytometric Bead Array in 40 HTLV-1-infected patients (11 HAM/TSP and 29 ACs) and 18 healthy controls (HCs) in Brazil. Among ACs, 15 were Japanese descendants and 14 were non-Japanese. Of 11 patients with HAM/TSP, only one was a Japanese descendant. The HTLV-1 PVL was quantified by real-time PCR. The HTLV-1 PVL was 2.7-fold higher in HAM/TSP patients than ACs. Regardless of the clinical outcome, the PVL was significantly higher in patients younger than 60 years than older patients. The HAM/TSP and ACs had higher IL-10 serum concentrations than that of HCs. The ACs also showed higher IL-6 serum levels than those of HCs. According to age, the IL-10 and IL-6 levels were higher in ACs non-Japanese patients older than 60 years. HAM/TSP patients showed a positive correlation between IL-6 and IL-17 and a negative correlation between the PVL and IL-17 and IFN-γ. In the all ACs, a significant positive correlation was observed between IL-2 and IL-17 and a negative correlation was detected between IL-10 and TNF-α. Only 6.25% of the Japanese patients were symptomatic carriers, compared with 41.67% of the non-Japanese patients. In conclusion, this study showed that high levels of HTLV-1 PVL was intrinsicaly associated with the development of HAM/TSP. A higher HTLV-1 PVL and IL10 levels found in non-Japanese ACs over 60 years old, which compared with the Japanese group depicts that the ethnic background may interfere in the host immune status. More researches also need to be undertaken regarding the host genetic background to better understand the low frequency of HAM/TSP in Japanese HTLV-1-infected individuals.

Cytokine profile and proviral load among Japanese immigrants and non-Japanese infected with HTLV-1 in a non-endemic area of Brazil

PubMed Central

Domingos, João Américo; Soares, Luana Silva; Bandeira, Larissa M.; Bonin, Camila Mareti; Vicente, Ana C. P.; Zanella, Louise; Puga, Marco Antonio Moreira; Tozetti, Inês Aparecida; Motta-Castro, Ana Rita Coimbra; da Cunha, Rivaldo Venâncio

2017-01-01

The lifetime risk of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) development differs among ethnic groups. To better understand these differences, this prospective cohort study was conducted to investigate the cytokine profile and the HTLV-1 proviral load (PVL) in Japanese and non-Japanese populations with HAM/TSP and asymptomatic carriers (ACs). The serum IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α, and IFN-γ levels were quantified using the Cytometric Bead Array in 40 HTLV-1-infected patients (11 HAM/TSP and 29 ACs) and 18 healthy controls (HCs) in Brazil. Among ACs, 15 were Japanese descendants and 14 were non-Japanese. Of 11 patients with HAM/TSP, only one was a Japanese descendant. The HTLV-1 PVL was quantified by real-time PCR. The HTLV-1 PVL was 2.7-fold higher in HAM/TSP patients than ACs. Regardless of the clinical outcome, the PVL was significantly higher in patients younger than 60 years than older patients. The HAM/TSP and ACs had higher IL-10 serum concentrations than that of HCs. The ACs also showed higher IL-6 serum levels than those of HCs. According to age, the IL-10 and IL-6 levels were higher in ACs non-Japanese patients older than 60 years. HAM/TSP patients showed a positive correlation between IL-6 and IL-17 and a negative correlation between the PVL and IL-17 and IFN-γ. In the all ACs, a significant positive correlation was observed between IL-2 and IL-17 and a negative correlation was detected between IL-10 and TNF-α. Only 6.25% of the Japanese patients were symptomatic carriers, compared with 41.67% of the non-Japanese patients. In conclusion, this study showed that high levels of HTLV-1 PVL was intrinsicaly associated with the development of HAM/TSP. A higher HTLV-1 PVL and IL10 levels found in non-Japanese ACs over 60 years old, which compared with the Japanese group depicts that the ethnic background may interfere in the host immune status. More researches also need to be undertaken regarding the host genetic background to better understand the low frequency of HAM/TSP in Japanese HTLV-1-infected individuals. PMID:28376092

An AC modulated near infrared gain calibration system for a “Violin-Mode” transimpedance amplifier, intended for advanced LIGO suspensions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lockerbie, N. A.; Tokmakov, K. V.

The background to this work was a prototype shadow sensor, which was designed for retro-fitting to an advanced LIGO (Laser Interferometer Gravitational wave Observatory) test-mass/mirror suspension, in which a 40 kg test-mass/mirror is suspended by four approximately 600 mm long by 0.4 mm diameter fused-silica suspension fibres. The shadow sensor comprised a LED source of Near InfraRed (NIR) radiation, and a “tall-thin” rectangular silicon photodiode detector, which together were to bracket the fibre under test. The photodiode was positioned so as to be sensitive (primarily) to transverse “Violin-Mode” vibrations of such a fibre, via the oscillatory movement of the shadowmore » cast by the fibre, as this moved across the face of the detector. In this prototype shadow sensing system the photodiode was interfaced to a purpose-built transimpedance amplifier, this having both AC and DC outputs. A quasi-static calibration was made of the sensor’s DC responsivity, i.e., incremental rate of change of output voltage versus fibre position, by slowly scanning a fused-silica fibre sample transversely through the illuminating beam. The work reported here concerns the determination of the sensor’s more important AC (Violin-Mode) responsivity. Recognition of the correspondence between direct AC modulation of the source, and actual Violin-Mode signals, and of the transformative role of the AC/DC gain ratio for the amplifier, at any modulation frequency, f, resulted in the construction of the AC/DC calibration source described here. A method for determining in practice the transimpedance AC/DC gain ratio of the photodiode and amplifier, using this source, is illustrated by a specific numerical example, and the gain ratio for the prototype sensing system is reported over the frequency range 1 Hz–300 kHz. In fact, a maximum DC responsivity of 1.26 kV.m{sup −1} was measured using the prototype photodiode sensor and amplifier discussed here. Therefore, the measured AC/DC transimpedance gain ratio of 922.5 for this sensor, at 500 Hz, translated into a maximum Violin-Mode (AC) responsivity of (1.16 ± 0.05) MV m{sup −1}, at that frequency.« less

Role of HSF1-upregulated AC6 in ameliorating heart failure in mice.

PubMed

The, Erlinda; Du, Peizhao; Chang, Yaowei; Dai, Fangjie; Wei, Chunyan; Li, Jiming

2016-10-01

Our previous studies discovered that Heat shock factor 1(HSF1) can alleviate pressure overload induced heart failure in mice. However, its molecular mechanisms are yet to be further explained. Many studies have already verified that Adenylyl Cyclase 6 (AC6) can ameliorate heart failure, but it is still unknown whether or not the pathway HSF1 is involved in the process. Our preliminary experiment showed that the expression level of AC6 is positively associated with HSF1. Therefore, in the present study, we aimed to explore whether HSF1 can play its role in ameliorating heart failure by regulating AC6, and how the potential internal mechanisms work. We applied the Transverse Aortic Constriction (TAC) for 4 weeks to develop the C57BL/6 mice pressure overload induced heart failure model. First, the mice were divided into TAC group and SHAM group. Changes in the cardiac function and morphology of the mice were observed by an ultrasonic device and Masson staining slices, expressions of AC6 mRNA were observed by RT-QPCR, expressions of HSF1 and proteinkinase A (PKA) were examined by Western Blotting, and the levels of cyclic adenosine monophosphate (cAMP) from aortic blood were measured by ELISA. Second, the TAC group were further divided into subgroups of HSF1 transgene mice, HSF1 knockout mice and wild type mice, followed by the aforesaid observations. In the SHAM group, no obvious variations of cardiac function, AC6 mRNAHSF1, PKA, cAMP and other test results were found among each of the subgroups. Compared to the SHAM group, the TAC group presented clearly weakened heart functions, while, expressions of AC6 mRNA, HSF1, PKA and cAMP all recorded obvious increases. In the TAC group, compared to the WT subgroup, the HSF1 KO subgroup presented decreases in expressions of AC6 mRNA, HSF1, PKA and cAMP, and at the same time, the heart functions were weaker, while, the HSF1 TG subgroup recorded the contrary results. In the pressure overload heart failure model, HSF1 can ameliorate heart failure by positively regulating the pathway of AC6/cAMP/PKA. Copyright © 2016 Elsevier B.V. All rights reserved.

Generalization of the Child-Langmuir law to the alternate extraction of positive and negative ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lafleur, T., E-mail: trevor.lafleur@lpp.polytechnique.fr; ONERA-The French Aerospace Lab, 91120 Palaiseau; Aanesland, A.

Using a combined analytical and simulation approach, we investigate positive and negative ion extraction between two electrodes from an ion-ion plasma source. With a square voltage waveform applied to the electrodes, we obtain approximate analytical solutions for the time-averaged extracted current densities, which are given simply by: J{sub p}{sup ac}=[α−fL√((M{sub p})/(q{sub p}V{sub 0}) )]J{sub p}{sup dc}, and J{sub n}{sup ac}=[(1−α)−fL√((M{sub n})/(q{sub n}V{sub 0}) )]J{sub n}{sup dc}, where J{sup ac} is the time-averaged current density, α is the square waveform duty cycle, f is the frequency, L is the electrode gap length, M is the ion mass, q is the ionmore » charge, V{sub 0} is the applied voltage amplitude, J{sup dc} is the dc extracted current density, and the subscripts p and n refer to positive and negative ions, respectively. In particular, if J{sup dc} is the dc space-charge limited current density, then these equations describe the square waveform generalization of the Child-Langmuir law.« less

Adalimumab Treatment in Biologically Naïve Crohn's Disease: Relationship with Ectopic MUC5AC Expression and Endoscopic Improvement

PubMed Central

Mizoshita, Tsutomu; Tanida, Satoshi; Tsukamoto, Hironobu; Ozeki, Keiji; Katano, Takahito; Nishiwaki, Hirotaka; Ebi, Masahide; Mori, Yoshinori; Kubota, Eiji; Kataoka, Hiromi; Kamiya, Takeshi; Joh, Takashi

2014-01-01

Background. Adalimumab (ADA) is effective for patients with Crohn's disease (CD). However, there have been few reports on ADA therapy with respect to its relationship with pathologic findings and drug efficacy in biologically naïve CD cases. Methods. Fifteen patients with active biologically naïve CD were treated with ADA. We examined them clinically and pathologically with ectopic MUC5AC expression in the lesions before and after 12 and 52 weeks of ADA therapy, retrospectively. Results. Both mean CD activity index scores and serum C-reactive protein values were significantly lower after ADA therapy (P < 0.001). In the MUC5AC negative group, all cases exhibited clinical remission (CR) and endoscopic improvement at 52 weeks. In MUC5AC positive groups, loss of MUC5AC expression was detected in cases having CR and endoscopic improvement at 52 weeks, while remnant ectopic MUC5AC expression was observed in those exhibiting no endoscopic improvement and flare up after 52 weeks. Conclusions. ADA leads to CR and endoscopic improvement in biologically naïve CD cases. In addition, ectopic MUC5AC expression may be a predictive marker of flare up and endoscopic improvement in the intestines of CD patients. PMID:24829572

Influence of sialic acids on the galactose-recognizing receptor of rat peritoneal macrophages.

PubMed

Lee, H Y; Kelm, S; Michalski, J C; Schauer, R

1990-04-01

The interaction of the galactose-recognizing receptor from rat peritoneal macrophages with ligands containing terminal galactose residues, such as asialoorosomucoid, desialylated erythrocytes or lymphocytes, can be inhibited by free N-acetylneuraminic acid (Neu5Ac) and oligosaccharides or glycoproteins containing this sugar in terminal position. This effect of Neu5Ac on the receptor is specific. The other naturally occurring or most of synthetic neuraminic acid derivatives tested do not exhibit an equivalent inhibitory potency as Neu5Ac. Although free Neu5Ac inhibits 5-fold stronger (K50 = 0.2mM) than free galactose, clustering of Neu5Ac in oligosaccharides and glycoproteins does not lead to stronger inhibition, which is in contrast to galactose-containing ligands. A more branched (triantennary) sialooligosaccharide inhibits less than biantennary and unbranched sialooligosaccharides. This may be the reason, why complex sialic acid-containing ligands like native orosomucoid or blood cells are not bound and internalized by the macrophages. The dissociation of asialoorosomucoid from the receptor is slow under the influence of Neu5Ac and requires relatively high concentrations of this sugar, whereas the dissociation mediated by galactose is rapid and requires lower concentrations. An allosteric influence of Neu5Ac on the binding of galactose by the receptor is discussed.

Value of heart-type fatty acid-binding protein (H-FABP) for emergency department patients with suspected acute coronary syndrome.

PubMed

Banu, Karakus Yilmaz; Niyazi, Ozüçelik Doğaç; Erdem, Cevik; Dpekçi Afşin, Doğan Hatice; Ozlem, Uzun; Yasemin, Celik; Afsin, Ipekci

2014-09-01

The aim of this study is testing the value of H-FABP in the early diagnosis of ACS alone or with routinely used biomarkers such as myoglobin, CK-MB, and cTn I in patients who admitted to emergency department (ED) with complaint of chest pain and suspected acute coronary syndrome. This prospective and cross-sectional study was performed at the Emergency Department of University hospital between June 2009 and September 2010. Patients who were admitted with chest pain within first 48 hours and suspected ACS were enrolled to the study. Blood samples were taken for CK-MB, myoglobin, cTnI and H-FABP The patients were divided into two groups (ACS and non ACS). Statistical analyse were used for relation of biomarkers with diagnosis of ACS. A 66 patients were included to the study. H-FAPB values were positive in 15.2% patients. When H-FABP was added to routinely used biomarkers in the diagnosis of ACS, increasing was observed in all sensitivity, specificity, PPV and NPV values. However, this increase was not statistically significant. H-FABP did not provide any significant change in early diagnosis and exclusion of ACS diagnosis when used either alone or combination with routinely used biomarkers.

An Optimized Method for the Measurement of Acetaldehyde by High-Performance Liquid Chromatography

PubMed Central

Guan, Xiangying; Rubin, Emanuel; Anni, Helen

2011-01-01

Background Acetaldehyde is produced during ethanol metabolism predominantly in the liver by alcohol dehydrogenase, and rapidly eliminated by oxidation to acetate via aldehyde dehydrogenase. Assessment of circulating acetaldehyde levels in biological matrices is performed by headspace gas chromatography and reverse phase high-performance liquid chromatography (RP-HPLC). Methods We have developed an optimized method for the measurement of acetaldehyde by RP-HPLC in hepatoma cell culture medium, blood and plasma. After sample deproteinization, acetaldehyde was derivatized with 2,4-dinitrophenylhydrazine (DNPH). The reaction was optimized for pH, amount of derivatization reagent,, time and temperature. Extraction methods of the acetaldehyde-hydrazone (AcH-DPN) stable derivative and product stability studies were carried out. Acetaldehyde was identified by its retention time in comparison to AcH-DPN standard, using a new chromatography gradient program, and quantitated based on external reference standards and standard addition calibration curves in the presence and absence of ethanol. Results Derivatization of acetaldehyde was performed at pH 4.0 with a 80-fold molar excess of DNPH. The reaction was completed in 40 min at ambient temperature, and the product was stable for 2 days. A clear separation of AcH-DNP from DNPH was obtained with a new 11-min chromatography program. Acetaldehyde detection was linear up to 80 μM. The recovery of acetaldehyde was >88% in culture media, and >78% in plasma. We quantitatively determined the ethanol-derived acetaldehyde in hepatoma cells, rat blood and plasma with a detection limit around 3 μM. The accuracy of the method was <9% for intraday and <15% for interday measurements, in small volume (70 μl) plasma sampling. Conclusions An optimized method for the quantitative determination of acetaldehyde in biological systems was developed using derivatization with DNPH, followed by a short RP-HPLC separation of AcH-DNP. The method has an extended linear range, is reproducible and applicable to small volume sampling of culture media and biological fluids. PMID:21895715

Interacting dynamic Wannier-Stark ladder driven by a periodic pulse train

NASA Astrophysics Data System (ADS)

Hino, Ken-Ichi; Tong, Xiao Min; Toshima, Nobuyuki

2008-01-01

The electronic structures of the Floquet states of the dynamic Wannier-Stark ladder (DWSL) are examined, where the DWSL is formed by driving the biased superlattices (SLs) by the periodic pulse train (PPT) with the electric field F(t) —with time t —and the temporal period 2π/ω . For a strong F(t) , interminiband interactions, namely, the ac-Zener tunneling (ac-ZT), are predominantly caused in the DWSL. Such a system is termed the interacting DWSL. In order to understand the details of the Floquet states and the modulation patterns by alteration of a couple of the PPT laser parameters, the linear absorption spectra, αabs(ωp;ω) , of optical interband transitions invoked by the monochromatic probe laser fp(t) with the frequency ωp are calculated, where the spectra are not only linear in fp(t) but also nonlinear in F(t) . The exciton effect is not included for the sake of simplicity. For the PPT driving with unit-pulse shapes largely deviated from the square and saw-toothed profiles, the spectra show unexpected dent structures, differing a great deal from the corresponding ac-ZT-free spectra basically similar to those of the original SLs just showing the ascending steplike structure. To deepen the understanding of this anomaly, the spectra of αabs0(ωp;ω)∝∂αabs(ωp;ω)/∂ωp are also calculated, whereby the dent structures become spectral dips showing the negative absorption. It is found that such anomalous behavior is attributed to the ac-ZT between different minibands that accompanies emission/absorption of the nonzero net number of photons with Jω (with J a nonzero integer). This anomaly also shows the unusual time dependence in the dual-time optical susceptibility associated with αabs0(ωp;ω) . Moreover, the possibility of existence of the negative absorption in the more realistic excitonic spectra is speculated.

An optimized method for the measurement of acetaldehyde by high-performance liquid chromatography.

PubMed

Guan, Xiangying; Rubin, Emanuel; Anni, Helen

2012-03-01

Acetaldehyde is produced during ethanol metabolism predominantly in the liver by alcohol dehydrogenase and rapidly eliminated by oxidation to acetate via aldehyde dehydrogenase. Assessment of circulating acetaldehyde levels in biological matrices is performed by headspace gas chromatography and reverse phase high-performance liquid chromatography (RP-HPLC). We have developed an optimized method for the measurement of acetaldehyde by RP-HPLC in hepatoma cell culture medium, blood, and plasma. After sample deproteinization, acetaldehyde was derivatized with 2,4-dinitrophenylhydrazine (DNPH). The reaction was optimized for pH, amount of derivatization reagent, time, and temperature. Extraction methods of the acetaldehyde-hydrazone (AcH-DNP) stable derivative and product stability studies were carried out. Acetaldehyde was identified by its retention time in comparison with AcH-DNP standard, using a new chromatography gradient program, and quantitated based on external reference standards and standard addition calibration curves in the presence and absence of ethanol. Derivatization of acetaldehyde was performed at pH 4.0 with an 80-fold molar excess of DNPH. The reaction was completed in 40 minutes at ambient temperature, and the product was stable for 2 days. A clear separation of AcH-DNP from DNPH was obtained with a new 11-minute chromatography program. Acetaldehyde detection was linear up to 80 μM. The recovery of acetaldehyde was >88% in culture media and >78% in plasma. We quantitatively determined the ethanol-derived acetaldehyde in hepatoma cells, rat blood and plasma with a detection limit around 3 μM. The accuracy of the method was <9% for intraday and <15% for interday measurements, in small volume (70 μl) plasma sampling. An optimized method for the quantitative determination of acetaldehyde in biological systems was developed using derivatization with DNPH, followed by a short RP-HPLC separation of AcH-DNP. The method has an extended linear range, is reproducible and applicable to small-volume sampling of culture media and biological fluids. Copyright © 2011 by the Research Society on Alcoholism.

Zero TE-based pseudo-CT image conversion in the head and its application in PET/MR attenuation correction and MR-guided radiation therapy planning.

PubMed

Wiesinger, Florian; Bylund, Mikael; Yang, Jaewon; Kaushik, Sandeep; Shanbhag, Dattesh; Ahn, Sangtae; Jonsson, Joakim H; Lundman, Josef A; Hope, Thomas; Nyholm, Tufve; Larson, Peder; Cozzini, Cristina

2018-02-18

To describe a method for converting Zero TE (ZTE) MR images into X-ray attenuation information in the form of pseudo-CT images and demonstrate its performance for (1) attenuation correction (AC) in PET/MR and (2) dose planning in MR-guided radiation therapy planning (RTP). Proton density-weighted ZTE images were acquired as input for MR-based pseudo-CT conversion, providing (1) efficient capture of short-lived bone signals, (2) flat soft-tissue contrast, and (3) fast and robust 3D MR imaging. After bias correction and normalization, the images were segmented into bone, soft-tissue, and air by means of thresholding and morphological refinements. Fixed Hounsfield replacement values were assigned for air (-1000 HU) and soft-tissue (+42 HU), whereas continuous linear mapping was used for bone. The obtained ZTE-derived pseudo-CT images accurately resembled the true CT images (i.e., Dice coefficient for bone overlap of 0.73 ± 0.08 and mean absolute error of 123 ± 25 HU evaluated over the whole head, including errors from residual registration mismatches in the neck and mouth regions). The linear bone mapping accounted for bone density variations. Averaged across five patients, ZTE-based AC demonstrated a PET error of -0.04 ± 1.68% relative to CT-based AC. Similarly, for RTP assessed in eight patients, the absolute dose difference over the target volume was found to be 0.23 ± 0.42%. The described method enables MR to pseudo-CT image conversion for the head in an accurate, robust, and fast manner without relying on anatomical prior knowledge. Potential applications include PET/MR-AC, and MR-guided RTP. © 2018 International Society for Magnetic Resonance in Medicine.

75 FR 50950 - Federal Speculative Position Limits for Referenced Energy Contracts and Associated Regulations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-18

... COMMODITY FUTURES TRADING COMMISSION 17 CFR Parts 1, 20, and 151 RIN 3038-AC85 Federal Speculative Position Limits for Referenced Energy Contracts and Associated Regulations AGENCY: Commodity Futures... Futures Trading Commission (``CFTC'' or ``Commission'') proposed to implement position limits for futures...

78 FR 5767 - Positive Train Control Systems (RRR)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-28

... [Docket No. FRA-2011-0061, Notice No. 2] RIN 2130-AC32 Positive Train Control Systems (RRR) AGENCY... positive train control (PTC) systems. The present document clarifies FRA's responses to several elements of... control by signal indication or mandatory directive; that the movement of non-PTC equipped locomotives and...

Accurate evaluation of fast threshold voltage shift for SiC MOS devices under various gate bias stress conditions

NASA Astrophysics Data System (ADS)

Sometani, Mitsuru; Okamoto, Mitsuo; Hatakeyama, Tetsuo; Iwahashi, Yohei; Hayashi, Mariko; Okamoto, Dai; Yano, Hiroshi; Harada, Shinsuke; Yonezawa, Yoshiyuki; Okumura, Hajime

2018-04-01

We investigated methods of measuring the threshold voltage (V th) shift of 4H-silicon carbide (SiC) metal–oxide–semiconductor field-effect transistors (MOSFETs) under positive DC, negative DC, and AC gate bias stresses. A fast measurement method for V th shift under both positive and negative DC stresses revealed the existence of an extremely large V th shift in the short-stress-time region. We then examined the effect of fast V th shifts on drain current (I d) changes within a pulse under AC operation. The fast V th shifts were suppressed by nitridation. However, the I d change within one pulse occurred even in commercially available SiC MOSFETs. The correlation between I d changes within one pulse and V th shifts measured by a conventional method is weak. Thus, a fast and in situ measurement method is indispensable for the accurate evaluation of I d changes under AC operation.

Effects of Bone Vibrator Position on Auditory Spatial Perception Tasks.

PubMed

McBride, Maranda; Tran, Phuong; Pollard, Kimberly A; Letowski, Tomasz; McMillan, Garnett P

2015-12-01

This study assessed listeners' ability to localize spatially differentiated virtual audio signals delivered by bone conduction (BC) vibrators and circumaural air conduction (AC) headphones. Although the skull offers little intracranial sound wave attenuation, previous studies have demonstrated listeners' ability to localize auditory signals delivered by a pair of BC vibrators coupled to the mandibular condyle bones. The current study extended this research to other BC vibrator locations on the skull. Each participant listened to virtual audio signals originating from 16 different horizontal locations using circumaural headphones or BC vibrators placed in front of, above, or behind the listener's ears. The listener's task was to indicate the signal's perceived direction of origin. Localization accuracy with the BC front and BC top positions was comparable to that with the headphones, but responses for the BC back position were less accurate than both the headphones and BC front position. This study supports the conclusion of previous studies that listeners can localize virtual 3D signals equally well using AC and BC transducers. Based on these results, it is apparent that BC devices could be substituted for AC headphones with little to no localization performance degradation. BC headphones can be used when spatial auditory information needs to be delivered without occluding the ears. Although vibrator placement in front of the ears appears optimal from the localization standpoint, the top or back position may be acceptable from an operational standpoint or if the BC system is integrated into headgear. © 2015, Human Factors and Ergonomics Society.

Stix Award: The ponderomotive effect beyond the ponderomotive force

NASA Astrophysics Data System (ADS)

Dodin, I. Y.

2014-10-01

The classical ponderomotive effect (PE) is typically understood as the nonlinear time-average force produced by a rapidly oscillating electromagnetic field on a nonresonant particle. It is instructive to contrast this understanding with the common quantum interpretation of the PE as the ac Stark shift, i.e., phase modulation, or a Kerr effect experienced by the wave function. Then the PE is naturally extended from particles to waves and can be calculated efficiently in general settings, including for strongly nonlinear interactions and resonant dynamics. In particular, photons (plasmons, etc.) are hence seen to have polarizability and contribute to the linear dielectric tensor exactly like ``true'' particles such as electrons and ions. The talk will briefly review the underlying variational theory and some nonintuitive PE-based techniques of wave and particle manipulation that the theory predicts. It will also be shown that the PE can be understood as the cause for the basic properties of both linear and nonlinear waves in plasma, including their dispersion, energy-momentum transport, and various modulational instabilities. Linear collisionless dissipation (both on particles and classical waves, treated on the same footing) also appears merely as a special case of the modulational dynamics. The work was supported by NNSA grant DE274-FG52-08NA28553, DOE contract DE-AC02-09CH11466, and DTRA grant HDTRA1-11-1-0037.

Cognitive impairment in rheumatoid arthritis: role of lymphocyte subsets, cytokines and neurotrophic factors.

PubMed

Petersen, Laura E; Baptista, Talita S A; Molina, Júlia K; Motta, Julia G; do Prado, Aline; Piovesan, Deise M; de Nardi, Tatiana; Viola, Thiago W; Vieira, Érica L M; Teixeira, Antonio L; Grassi-Oliveira, Rodrigo; Bauer, Moisés Evandro

2018-05-01

To what extent the cognitive impairment of rheumatoid arthritis (RA) is modulated by autoimmune and/or inflammatory activity is largely unknown. The aim of this study was to investigate the role of peripheral inflammation on cognitive functions of patients with active (Ac-), controlled (Co-) RA and healthy controls. In a cross-sectional study, 102 RA patients and 30 matched healthy controls were recruited. B and T cell subsets were immunophenotyped by flow cytometry. Plasma cytokines and neurotrophins were measured by flow cytometry and ELISA, respectively. Cognitive performance, depression and stress were evaluated by structured clinical interviews. Generalized linear modeling (GzLM) was used to compare differences between groups and multiple linear regression models were used to explore the predictive value of immune variables on cognitive performance. RA patients had overall cognitive impairment. Of note, the Ac-RA had the poorest performance on digit span (DST) and N-back when compared to Co-RA and control group (DST 9.9 ± 2.1, 12.9 ± 4.2, 15.5 ± 4.7, respectively; N-back 49.2 ± 8.3, 55.5 ± 11.1, 60.8 ± 9.1, respectively, all p < 0.0001). RA patients had expansions of immature B cells (Ac-RA 11.2 ± 7.1, Co-RA: 9 ± 5.7, control 5.9 ± 2.1) and plasma cells (Ac-RA 5.2 ± 2.5, Co-RA 6.9 ± 3.7, control 2.8 ± 1.7) as compared to controls, all p < 0.05. RA patients (controlled and active disease) had higher plasma levels of TNF, IL-2, IL-4, IL-6 and IL-10 than controls (all p < 0.002). RA patients had higher BDNF levels (Ac-RA 17,354.4 ± 5357.3, Co-RA 13,841.2 ± 5953.7, control 11,543.3 ± 3772), but lower GDNF levels [median (interquartile range) Ac-RA 0 pg/ml (0.0), Co-RA 0 pg/ml (4.6) and control 4.7 pg/ml (18.1)] than controls (all p < 0.05). RA patients had global cognitive impairment, which was associated with disease activity and immune changes.

Controlled vaporized cannabis, with and without alcohol: subjective effects and oral fluid-blood cannabinoid relationships.

PubMed

Hartman, Rebecca L; Brown, Timothy L; Milavetz, Gary; Spurgin, Andrew; Gorelick, David A; Gaffney, Gary; Huestis, Marilyn A

2016-07-01

Vaporized cannabis and concurrent cannabis and alcohol intake are commonplace. We evaluated the subjective effects of cannabis, with and without alcohol, relative to blood and oral fluid (OF, advantageous for cannabis exposure screening) cannabinoid concentrations and OF/blood and OF/plasma vaporized-cannabinoid relationships. Healthy adult occasional-to-moderate cannabis smokers received a vaporized placebo or active cannabis (2.9% and 6.7% Δ(9) -tetrahydrocannabinol, THC) with or without oral low-dose alcohol (~0.065g/210L peak breath alcohol concentration [BrAC]) in a within-subjects design. Blood and OF were collected up to 8.3 h post-dose and subjective effects measured at matched time points with visual-analogue scales and 5-point Likert scales. Linear mixed models evaluated subjective effects by THC concentration, BrAC, and interactions. Effects by time point were evaluated by dose-wise analysis of variance (ANOVA). OF versus blood or plasma cannabinoid ratios and correlations were evaluated in paired-positive specimens. Nineteen participants (13 men) completed the study. Blood THC concentration or BrAC significantly associated with subjective effects including 'high', while OF contamination prevented significant OF concentration associations <1.4 h post-dose. Subjective effects persisted through 3.3-4.3 h, with alcohol potentiating the duration of the cannabis effects. Effect-versus-THC concentration and effect-versus-alcohol concentration hystereses were counterclockwise and clockwise, respectively. OF/blood and OF/plasma THC significantly correlated (all Spearman r≥0.71), but variability was high. Vaporized cannabis subjective effects were similar to those previously reported after smoking, with duration extended by concurrent alcohol. Cannabis intake was identified by OF testing, but OF concentration variability limited interpretation. Blood THC concentrations were more consistent across subjects and more accurate at predicting cannabis' subjective effects. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Off-line solid phase extraction and liquid chromatography-tandem mass spectrometry method for the quantitation of brivaracetam acid metabolites: Method validation and application to in vitro metabolism assays.

PubMed

Bourgogne, Emmanuel; Culot, Benoit; Dell'Aiera, Sylvie; Chanteux, Hugues; Stockis, Armel; Nicolas, Jean-Marie

2018-06-01

Brivaracetam (BRV) is a new high affinity synaptic vesicle protein 2A ligand recently approved for adults with partial-onset seizures. As a support to in vitro metabolism assays, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method coupled to off-line solid phase extraction (SPE) was developed to quantify BRV acid metabolites, that is, BRV-AC (carboxylic derivative derived from BRV hydrolysis) and BRV-OHAC (corresponding to hydroxylated BRV-AC). The method was validated for various incubates (liver and kidney tissue homogenates and blood, all from humans) and applied to in vitro metabolism assays. The analytes were isolated from buffered samples using ISOLUTE C8 96-well SPE plates. Chromatographic separation was achieved on a Waters Atlantis T3 C18 analytical column (2.1 mm × 50 mm, 5 μm) with detection accomplished using a Waters Premier tandem mass spectrometer in positive ion electrospray and multiple reaction monitoring (MRM) mode. The standard curves, which ranged from 1.00 to 200 ng/mL for BRV-AC, BRV-OHAC, were fitted to a 1/x 2 weighted linear regression model. The intra-assay precision and inter-assay precision (expressed as coefficient of variation -%CV) were <8.5%, and the assay accuracy (deviation - %Dev) was within ±7.1% for the different matrices. This accurate, precise, and selective SPE/LC-MS/MS method has been successfully applied to in vitro assays aimed at characterizing the kinetics of BRV hydrolysis. BRV was found to be a better substrate for hydrolysis than its hydroxylated metabolite BRV-OH. BRV hydrolysis was detected in blood, liver and kidneys, demonstrating the broad distribution of the enzyme catalyzing the reaction. Copyright © 2018 Elsevier B.V. All rights reserved.

Acute care surgery: now that we have built it, will they come?

PubMed

Coleman, Jamie J; Esposito, Thomas J; Rozycki, Grace S; Feliciano, David V

2013-02-01

Concern over lack of resident interest caused by the nonoperative nature and compromised lifestyle associated with a career as a "trauma surgeon" has led to the emergence of a new acute care surgery (ACS) specialty. This study examined the opinions of current general surgical residents about training and careers in this new field. A 36-item online anonymous survey regarding ACS was sent to the program directors of 55 randomly selected general surgery (GS) training programs for distribution to their categorical residents. The national sample consisted of 1,515 PGY 1 to 5 trainees. Response rate was 45%. More than 90% of residents had an appropriate understanding of the components of ACS as generally described (trauma, surgical critical care, and emergency GS). Nearly half (46%) of all respondents have considered ACS as a career. Overall, ACS ranked as the second most appealing career ahead of surgical critical care and trauma but behind GS. Most residents believed that ACS offers better or equivalent case complexity (88%), scope of practice (84%), case volume (75%), and level of reimbursement (69%) compared with GS alone. Respondents who answered ACS had a better scope of practice (61% vs. 36%), lifestyle as an attending surgeon (77% vs. 34%), or level of reimbursement (83% vs. 38%) compared with GS were twice as likely (p < 0.0001) to have considered ACS as a career. Overall, 40% of the residents believed that ACS offers a worse lifestyle in comparison with GS. These results suggest that there is notable interest in the emerging specialty of ACS. The level of resident interest in ACS as a fellowship and career may be increased by marketing those aspects of practice, which are viewed positively and addressing negative perceptions related to lifestyle. It may be appealing to add an elective GS component to certain ACS practice options.

Study on AC loss measurements of HTS power cable for standardizing

NASA Astrophysics Data System (ADS)

Mukoyama, Shinichi; Amemiya, Naoyuki; Watanabe, Kazuo; Iijima, Yasuhiro; Mido, Nobuhiro; Masuda, Takao; Morimura, Toshiya; Oya, Masayoshi; Nakano, Tetsutaro; Yamamoto, Kiyoshi

2017-09-01

High-temperature superconducting power cables (HTS cables) have been developed for more than 20 years. In addition of the cable developments, the test methods of the HTS cables have been discussed and proposed in many laboratories and companies. Recently the test methods of the HTS cables is required to standardize and to common in the world. CIGRE made the working group (B1-31) for the discussion of the test methods of the HTS cables as a power cable, and published the recommendation of the test method. Additionally, IEC TC20 submitted the New Work Item Proposal (NP) based on the recommendation of CIGRE this year, IEC TC20 and IEC TC90 started the standardization work on Testing of HTS AC cables. However, the individual test method that used to measure a performance of HTS cables hasn’t been established as world’s common methods. The AC loss is one of the most important properties to disseminate low loss and economical efficient HTS cables in the world. We regard to establish the method of the AC loss measurements in rational and in high accuracy. Japan is at a leading position in the AC loss study, because Japanese researchers have studied on the AC loss technically and scientifically, and also developed the effective technologies for the AC loss reduction. The JP domestic commission of TC90 made a working team to discussion the methods of the AC loss measurements for aiming an international standard finally. This paper reports about the AC loss measurement of two type of the HTS conductors, such as a HTS conductor without a HTS shield and a HTS conductor with a HTS shield. The AC loss measurement method is suggested by the electrical method..

TNT Biodegradation by Natural Microbial Assemblages at Estuarine Frontal Boundaries

DTIC Science & Technology

2012-07-02

component acid, aldehyde , and ketone phenols after microwave assisted CuO-oxidation (Louchouarn et al. 2000, Goni and Montgomery 2000). Phenols...Oahu, HI, USA (20 July 2010). vii LIST OF ACRONYMS Ac:Ad: Ratio of Acid to Aldehyde Moieties ASI: Air-Sea Interface BIX: Biological... aldehyde moieties for vanillyl phenols (Ac:Alv), an index of oxidative degradation for lignin, was positively correlated with fraction of C1 in the

Genome-wide miRNA response to anacardic acid in breast cancer cells

PubMed Central

Schultz, David J.; Muluhngwi, Penn; Alizadeh-Rad, Negin; Green, Madelyn A.; Rouchka, Eric C.; Waigel, Sabine J.

2017-01-01

MicroRNAs are biomarkers and potential therapeutic targets for breast cancer. Anacardic acid (AnAc) is a dietary phenolic lipid that inhibits both MCF-7 estrogen receptor α (ERα) positive and MDA-MB-231 triple negative breast cancer (TNBC) cell proliferation with IC50s of 13.5 and 35 μM, respectively. To identify potential mediators of AnAc action in breast cancer, we profiled the genome-wide microRNA transcriptome (microRNAome) in these two cell lines altered by the AnAc 24:1n5 congener. Whole genome expression profiling (RNA-seq) and subsequent network analysis in MetaCore Gene Ontology (GO) algorithm was used to characterize the biological pathways altered by AnAc. In MCF-7 cells, 69 AnAc-responsive miRNAs were identified, e.g., increased let-7a and reduced miR-584. Fewer, i.e., 37 AnAc-responsive miRNAs were identified in MDA-MB-231 cells, e.g., decreased miR-23b and increased miR-1257. Only two miRNAs were increased by AnAc in both cell lines: miR-612 and miR-20b; however, opposite miRNA arm preference was noted: miR-20b-3p and miR-20b-5p were upregulated in MCF-7 and MDA-MB-231, respectively. miR-20b-5p target EFNB2 transcript levels were reduced by AnAc in MDA-MB-231 cells. AnAc reduced miR-378g that targets VIM (vimentin) and VIM mRNA transcript expression was increased in AnAc-treated MCF-7 cells, suggesting a reciprocal relationship. The top three enriched GO terms for AnAc-treated MCF-7 cells were B cell receptor signaling pathway and ribosomal large subunit biogenesis and S-adenosylmethionine metabolic process for AnAc-treated MDA-MB-231 cells. The pathways modulated by these AnAc-regulated miRNAs suggest that key nodal molecules, e.g., Cyclin D1, MYC, c-FOS, PPARγ, and SIN3, are targets of AnAc activity. PMID:28886127

Uroplakin II Expression in Breast Carcinomas Showing Apocrine Differentiation: Putting Some Emphasis on Invasive Pleomorphic Lobular Carcinoma as a Potential Mimic of Urothelial Carcinoma at Metastatic Sites.

PubMed

Tajima, Shogo; Koda, Kenji

2016-01-01

Uroplakin II antibody is exclusively specific for urothelial carcinoma. Nonurothelial carcinoma has not been reported to be immunoreactive for uroplakin II. In the present study, we hypothesized that breast carcinoma showing apocrine differentiation, such as invasive pleomorphic lobular carcinoma (IPLC) and apocrine carcinoma (AC), stains positive for uroplakin II. We identified 6 cases of IPLC between 2000 and 2014 by searching a computerized pathological database. We randomly selected 10 cases of each classic invasive lobular carcinoma (cILC) and AC and five cases of apocrine metaplasia (AM) that coexisted in a surgically resected breast carcinoma specimen. Immunohistochemistry was performed for uroplakin II, GATA3, CK7, CK20, and other representative markers positive for urothelial carcinoma. All cases of IPLC, AC, and AM, except those of cILC, showed immunoreactivity for uroplakin II. Poorly differentiated urothelial carcinoma sometimes shows similar morphology to IPLC with the following immunophenotype: CK7+, CK20-, GATA3+, and uroplakin II+. In the present study, this immunophenotype was observed in all the cases of IPLC and AC. Therefore, when studying metastatic, poorly differentiated carcinoma showing the aforementioned immunophenotype, we should consider the possibility of it being IPLC in addition to metastatic urothelial carcinoma.

Preliminary investigation of the effects of γ-tACS on working memory in schizophrenia.

PubMed

Hoy, Kate E; Whitty, Dean; Bailey, Neil; Fitzgerald, Paul B

2016-10-01

Working memory impairment in schizophrenia has been strongly associated with abnormalities in gamma oscillations within the dorsolateral prefrontal cortex (DLFPC). We recently published the first ever study showing that anodal transcranial direct current stimulation (tDCS) to the left DLPFC was able to significantly improve working memory in schizophrenia and did so seemingly via restoring normal gamma oscillatory function. Transcranial alternating current stimulation (tACS) is a form of electrical brain stimulation that delivers stimulation at a specific frequency and has been shown to entrain endogenous cortical oscillations. Therefore, gamma (γ) tACS may be even more effective than tDCS in improving working memory in schizophrenia. In a randomized repeated-measures study we compared the effects of γ-tACS, tDCS and sham stimulation on the performance of the two back working memory tasks in ten patients with schizophrenia. There was a significant time by stimulation interaction, with tDCS and sham showing trend-level improvements in working memory, while γ-tACS, contrary to our hypothesis, showed no change. The results are discussed in light of posited divergent effects of tACS and tDCS on the pathophysiology of working memory impairment in schizophrenia.

Assessment of self taken swabs versus clinician taken swab cultures for diagnosing gonorrhoea in women: single centre, diagnostic accuracy study.

PubMed

Stewart, Catherine M W; Schoeman, Sarah A; Booth, Russell A; Smith, Susan D; Wilcox, Mark H; Wilson, Janet D

2012-12-12

To compare gonorrhoea detection by self taken vulvovaginal swabs (tested with nucleic acid amplification tests) with the culture of urethral and endocervical samples taken by clinicians. Prospective study of diagnostic accuracy. 1 sexual health clinic in an urban setting (Leeds Centre for Sexual Health, United Kingdom), between March 2009 and January 2010. Women aged 16 years or older, attending the clinic for sexually transmitted infection (STI) testing and consenting to perform a vulvovaginal swab themselves before routine examination. During examination, clinicians took urethral and endocervical samples for culture and an endocervical swab for nucleic acid amplification testing. Urethra and endocervix samples were analysed by gonococcal culture. Vulvovaginal swabs and endocervical swabs were analysed by the Aptima Combo 2 (AC2) assay; positive results from this assay were confirmed with a second nucleic acid amplification test. Positive confirmation of gonorrhoea. Of 3859 women with complete data and test results, 96 (2.5%) were infected with gonorrhoea (overall test sensitivities: culture 81%, endocervical swabs with AC2 96%, vulvovaginal swabs with AC2 99%). The AC2 assays were more sensitive than culture (P<0.001), but the endocervical and vulvovaginal assays did not differ significantly (P=0.375). Specificity of all Aptima Combo 2 tests was 100%. Of 1625 women who had symptoms suggestive of a bacterial STI, 56 (3.4%) had gonorrhoea (culture 84%, endocervical AC2 100%, vulvovaginal AC2 100%). The AC2 assays were more sensitive than culture (P=0.004), and the endocervical and vulvovaginal assays were equivalent to each other. Of 2234 women who did not have symptoms suggesting a bacterial STI, 40 (1.8%) had gonorrhoea (culture 78%, endocervical AC2 90%, vulvovaginal AC2 98%). The vulvovaginal swab was more sensitive than culture (P=0.008), but there was no difference between the endocervical and vulvovaginal AC2 assays (P=0.375) or between the endocervical AC2 assay and culture (P=0.125). The endocervical swab assay performed less well in women without symptoms of a bacterial STI than in those with symptoms (90% v 100%, P=0.028), whereas the vulvovaginal swab assay performed similarly (98% v 100%, P=0.42). Self taken vulvovaginal swabs analysed by nucleic acid amplification tests are significantly more sensitive at detecting gonorrhoea than culture of clinician taken urethral and endocervical samples, and are equivalent to endocervical swabs analysed by nucleic acid amplification tests. Self taken vulvovaginal swabs are the sample of choice in women without symptoms and have the advantage of being non-invasive. In women who need a clinical examination, either a clinician taken or self taken vulvovaginal swab is recommended.

Whole-body hybrid imaging concept for the integration of PET/MR into radiation therapy treatment planning.

PubMed

Paulus, Daniel H; Oehmigen, Mark; Grüneisen, Johannes; Umutlu, Lale; Quick, Harald H

2016-05-07

Modern radiation therapy (RT) treatment planning is based on multimodality imaging. With the recent availability of whole-body PET/MR hybrid imaging new opportunities arise to improve target volume delineation in RT treatment planning. This, however, requires dedicated RT equipment for reproducible patient positioning on the PET/MR system, which has to be compatible with MR and PET imaging. A prototype flat RT table overlay, radiofrequency (RF) coil holders for head imaging, and RF body bridges for body imaging were developed and tested towards PET/MR system integration. Attenuation correction (AC) of all individual RT components was performed by generating 3D CT-based template models. A custom-built program for μ-map generation assembles all AC templates depending on the presence and position of each RT component. All RT devices were evaluated in phantom experiments with regards to MR and PET imaging compatibility, attenuation correction, PET quantification, and position accuracy. The entire RT setup was then evaluated in a first PET/MR patient study on five patients at different body regions. All tested devices are PET/MR compatible and do not produce visible artifacts or disturb image quality. The RT components showed a repositioning accuracy of better than 2 mm. Photon attenuation of  -11.8% in the top part of the phantom was observable, which was reduced to  -1.7% with AC using the μ-map generator. Active lesions of 3 subjects were evaluated in terms of SUVmean and an underestimation of  -10.0% and  -2.4% was calculated without and with AC of the RF body bridges, respectively. The new dedicated RT equipment for hybrid PET/MR imaging enables acquisitions in all body regions. It is compatible with PET/MR imaging and all hardware components can be corrected in hardware AC by using the suggested μ-map generator. These developments provide the technical and methodological basis for integration of PET/MR hybrid imaging into RT planning.

Stress-only myocardial perfusion scintigraphy: a prospective study on the accuracy and observer agreement with quantitative coronary angiography as the gold standard.

PubMed

Ejlersen, June A; May, Ole; Mortensen, Jesper; Nielsen, Gitte L; Lauridsen, Jeppe F; Allan, Johansen

2017-11-01

Patients with normal stress perfusion have an excellent prognosis. Prospective studies on the diagnostic accuracy of stress-only scans with contemporary, independent examinations as gold standards are lacking. A total of 109 patients with typical angina and no previous coronary artery disease underwent a 2-day stress (exercise)/rest, gated, and attenuation-corrected (AC), 99m-technetium-sestamibi perfusion study, followed by invasive coronary angiography. The stress datasets were evaluated twice by four physicians with two different training levels (expert and novice): familiar and unfamiliar with AC. The two experts also made a consensus reading of the integrated stress-rest datasets. The consensus reading and quantitative data from the invasive coronary angiography were applied as reference methods. The sensitivity/specificity were 0.92-1.00/0.73-0.90 (reference: expert consensus reading), 0.93-0.96/0.63-0.82 (reference: ≥1 stenosis>70%), and 0.75-0.88/0.70-0.88 (reference: ≥1 stenosis>50%). The four readers showed a high and fairly equal sensitivity independent of their familiarity with AC. The expert familiar with AC had the highest specificity independent of the reference method. The intraobserver and interobserver agreements on the stress-only readings were good (readers without AC experience) to excellent (readers with AC experience). AC stress-only images yielded a high sensitivity independent of the training level and experience with AC of the nuclear physician, whereas the specificity correlated positively with both. Interobserver and intraobserver agreements tended to be the best for physicians with AC experience.

Ambient temperature and emergency room admissions for acute coronary syndrome in Taiwan

NASA Astrophysics Data System (ADS)

Liang, Wen-Miin; Liu, Wen-Pin; Chou, Sze-Yuan; Kuo, Hsien-Wen

2008-01-01

Acute coronary syndrome (ACS) is an important public health problem around the world. Since there is a considerable seasonal fluctuation in the incidence of ACS, climatic temperature may have an impact on the onset of this disease. The objective of this study was to assess the relationship between the average daily temperature, diurnal temperature range and emergency room (ER) admissions for ACS in an ER in Taichung City, Taiwan. A longitudinal study was conducted which assessed the correlation of the average daily temperature and the diurnal temperature range to ACS admissions to the ER of the city’s largest hospital. Daily ER admissions for ACS and ambient temperature were collected from 1 January 2000 to 31 March 2003. The Poisson regression model was used in the analysis after adjusting for the effects of holiday, season, and air pollutant concentrations. The results showed that there was a negative significant association between the average daily temperature and ER admissions for ACS. ACS admissions to the ER increased 30% to 70% when the average daily temperature was lower than 26.2°C. A positive association between the diurnal temperature range and ACS admissions was also noted. ACS admissions increased 15% when the diurnal temperature range was over 8.3°C. The data indicate that patients suffering from cardiovascular disease must be made aware of the increased risk posed by lower temperatures and larger changes in temperature. Hospitals and ERs should take into account the increased demand of specific facilities during colder weather and wider temperature variations.

Anti-fibrinolytic and anti-microbial activities of a serine protease inhibitor from honeybee (Apis cerana) venom.

PubMed

Yang, Jie; Lee, Kwang Sik; Kim, Bo Yeon; Choi, Yong Soo; Yoon, Hyung Joo; Jia, Jingming; Jin, Byung Rae

2017-10-01

Bee venom contains a variety of peptide constituents, including low-molecular-weight protease inhibitors. While the putative low-molecular-weight serine protease inhibitor Api m 6 containing a trypsin inhibitor-like cysteine-rich domain was identified from honeybee (Apis mellifera) venom, no anti-fibrinolytic or anti-microbial roles for this inhibitor have been elucidated. In this study, we identified an Asiatic honeybee (A. cerana) venom serine protease inhibitor (AcVSPI) that was shown to act as a microbial serine protease inhibitor and plasmin inhibitor. AcVSPI was found to consist of a trypsin inhibitor-like domain that displays ten cysteine residues. Interestingly, the AcVSPI peptide sequence exhibited high similarity to the putative low-molecular-weight serine protease inhibitor Api m 6, which suggests that AcVSPI is an allergen Api m 6-like peptide. Recombinant AcVSPI was expressed in baculovirus-infected insect cells, and it demonstrated inhibitory activity against trypsin, but not chymotrypsin. Additionally, AcVSPI has inhibitory effects against plasmin and microbial serine proteases; however, it does not have any detectable inhibitory effects on thrombin or elastase. Consistent with these inhibitory effects, AcVSPI inhibited the plasmin-mediated degradation of fibrin to fibrin degradation products. AcVSPI also bound to bacterial and fungal surfaces and exhibited anti-microbial activity against fungi as well as gram-positive and gram-negative bacteria. These findings demonstrate the anti-fibrinolytic and anti-microbial roles of AcVSPI as a serine protease inhibitor. Copyright © 2017 Elsevier Inc. All rights reserved.

Air conditioning impact on the dynamics of radon and its daughters concentration.

PubMed

Kozak, Krzysztof; Grządziel, Dominik; Połednik, Bernard; Mazur, Jadwiga; Dudzińska, Marzenna R; Mroczek, Mariusz

2014-12-01

Radon and its decay products are harmful pollutants present in indoor air and are responsible for the majority of the effective dose due to ionising radiation that people are naturally exposed to. The paper presents the results of the series of measurements of radon and its progeny (in unattached and attached fractions) as well as indoor air parameters: temperature, relative humidity, number and mass concentrations of fine aerosol particles. The measurements were carried out in the auditorium (lecture hall), which is an indoor air quality laboratory, in controlled conditions during two periods of time: when air conditioning (AC) was switched off (unoccupied auditorium) and when it was switched on (auditorium in normal use). The significant influence of AC and of students' presence on the dynamics of radon and its progeny was confirmed. A decrease in the mean value of radon and its attached progeny was found when AC was working. The mean value of radon equilibrium factor F was also lower when AC was working (0.49) than when it was off (0.61). The linear correlations were found between attached radon progeny concentration and particle number and mass concentration only when the AC was switched off. This research is being conducted with the aim to study the variability of radon equilibrium factor F which is essential to determine the effective dose due to radon and its progeny inhalation. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The relationship between heart-carotid pulse transit time and carotid intima-media thickness in hypertensive patients.

PubMed

Li, C; Xiong, H; Wu, W; Tian, X; Wang, Y; Wu, D; Lin, W-H; Miao, F; Zhang, H; Huang, W; Zhang, Y-T

2015-11-01

The study aimed to investigate the relationship between heart-carotid pulse transit time and carotid intima-media thickness (CIMT) in hypertensive patients, and whether including the pre-ejection period (PEP) in heart-carotid pulse transit time would affect this correlation. A total of 62 hypertensive patients were included in this study. They were divided into the normal CIMT group (n=33, CIMT⩽0.8 mm) and the thickened CIMT group (n=29, CIMT>0.8 mm). The noninvasive ultrasound method was used to measure CIMT, electrocardiogram R-wave-based heart-carotid pulse transit time (rcPTT) and PEP. Aortic valve-carotid artery pulse transit time (acPTT) was calculated by subtracting PEP from rcPTT. Simple linear analysis showed that CIMT was negatively associated with rcPTT and acPTT (r=-0.57, P<0.0001; r=-0.41, P=0.016) in the normal CIMT group as well as in the thickened CIMT group (r=-0.50, P=0.0053; r=-0.59, P=0.001). These relationships were eliminated in the normal CIMT group after adjusting for age, gender, smoking behaviour, systolic blood pressure, diastolic blood pressure and cholesterol levels. However, rcPTT and acPTT still showed significant correlations with CIMT in the thickened CIMT group. In conclusion, rcPTT and acPTT were associated with CIMT, independent of well-known clinical confounders in thickened CIMT hypertensive patients. Therefore, rcPTT and acPTT might be useful markers for atherosclerosis evaluation.

Linear Power-Flow Models in Multiphase Distribution Networks: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bernstein, Andrey; Dall'Anese, Emiliano

This paper considers multiphase unbalanced distribution systems and develops approximate power-flow models where bus-voltages, line-currents, and powers at the point of common coupling are linearly related to the nodal net power injections. The linearization approach is grounded on a fixed-point interpretation of the AC power-flow equations, and it is applicable to distribution systems featuring (i) wye connections; (ii) ungrounded delta connections; (iii) a combination of wye-connected and delta-connected sources/loads; and, (iv) a combination of line-to-line and line-to-grounded-neutral devices at the secondary of distribution transformers. The proposed linear models can facilitate the development of computationally-affordable optimization and control applications -- frommore » advanced distribution management systems settings to online and distributed optimization routines. Performance of the proposed models is evaluated on different test feeders.« less

Premature Cardiac Aging in South Asian Compared to Afro-Caribbean Subjects in a Community-Based Screening Study.

PubMed

Shantsila, Eduard; Shantsila, Alena; Gill, Paramjit S; Lip, Gregory Y H

2016-11-10

People of South Asian (SAs) and African Caribbean (AC) origin have increased cardiovascular morbidity, but underlying mechanisms are poorly understood. Aging is the key predictor of deterioration in diastolic function, which can be assessed by echocardiography using E/e' ratio as a surrogate of left ventricular (LV) filling pressure. The study aimed to assess a possibility of premature cardiac aging in SA and AC subjects. We studied 4540 subjects: 2880 SA and 1660 AC subjects. All participants underwent detailed echocardiography, including LV ejection fraction, average septal-lateral E/e', and LV mass index (LVMI). When compared to ACs, SAs were younger, with lower mean LVMI, systolic blood pressure (BP), diastolic BP, and body mass index (BMI), as well as a lower prevalence of hypertension and smoking (P≤0.001 for all). In a multivariate linear regression model including age, sex, ethnicity, BP, heart rate, BMI, waist circumference, LVMI, history of smoking, hypertension, coronary artery disease, diabetes mellitus, medications, SA origin was independently associated with higher E/e' (regression coefficient±standard error, -0.66±0.10; P<0.001, adjusted R 2 for the model 0.21; P<0.001). Furthermore, SAs had significantly accelerated age-dependent increase in E/e' compared to ACs. On multivariable Cox regression analysis without adjustment for E/e', SA ethnicity was independently predictive of mortality (P=0.04). After additional adjustment for E/e', the ethnicity lost its significance value, whereas E/e' was independently predictive of higher risk of death (P=0.008). Premature cardiac aging is evident in SAs and may contribute to high cardiovascular morbidity in this ethnic group, compared to ACs. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Testing item response theory invariance of the standardized Quality-of-life Disease Impact Scale (QDIS(®)) in acute coronary syndrome patients: differential functioning of items and test.

PubMed

Deng, Nina; Anatchkova, Milena D; Waring, Molly E; Han, Kyung T; Ware, John E

2015-08-01

The Quality-of-life (QOL) Disease Impact Scale (QDIS(®)) standardizes the content and scoring of QOL impact attributed to different diseases using item response theory (IRT). This study examined the IRT invariance of the QDIS-standardized IRT parameters in an independent sample. The differential functioning of items and test (DFIT) of a static short-form (QDIS-7) was examined across two independent sources: patients hospitalized for acute coronary syndrome (ACS) in the TRACE-CORE study (N = 1,544) and chronically ill US adults in the QDIS standardization sample. "ACS-specific" IRT item parameters were calibrated and linearly transformed to compare to "standardized" IRT item parameters. Differences in IRT model-expected item, scale and theta scores were examined. The DFIT results were also compared in a standard logistic regression differential item functioning analysis. Item parameters estimated in the ACS sample showed lower discrimination parameters than the standardized discrimination parameters, but only small differences were found for thresholds parameters. In DFIT, results on the non-compensatory differential item functioning index (range 0.005-0.074) were all below the threshold of 0.096. Item differences were further canceled out at the scale level. IRT-based theta scores for ACS patients using standardized and ACS-specific item parameters were highly correlated (r = 0.995, root-mean-square difference = 0.09). Using standardized item parameters, ACS patients scored one-half standard deviation higher (indicating greater QOL impact) compared to chronically ill adults in the standardization sample. The study showed sufficient IRT invariance to warrant the use of standardized IRT scoring of QDIS-7 for studies comparing the QOL impact attributed to acute coronary disease and other chronic conditions.

[Social support status and related influential factors of patients with acute coronary syndrome].

PubMed

Lei, S; Ding, R J; Wang, L; Xia, K; Zhang, L J; Yao, D K; Hu, D Y

2017-05-24

Objectives: To investigate the social support status, related influential factors and the impact on one year outcome in patients with acute coronary syndrome (ACS), our data might be helpful to provide basis for making new treatment strategy aimed at improving social support for patients with ACS. Methods: From January 2013 to June 2014, a total of 778 hospitalized patients with ACS were enrolled in the study. All patients completed enhancing recovery in coronary heart disease patients social support inventory(ESSI), general anxiety disorder scale(GAD-7), patient health questionnaire(PHQ-9), short-form 12 health survey questionnaire(SF-12), sleep questionnaire and demographic questionnaire within 7 days after admission and at 6 months and one year post discharge. Multiple linear regressions were performed to analyze factors that influenced the social support. Results: The total score of social support was 17.08±3.61, 17.72±3.04, and 17.76±3.05 respectively in patients with ACS at baseline, 6 months and 12 months after discharge. Patients had a higher point of social support at 6 months ( t =-2.69, P <0.01) and 12 months ( t =-2.86, P <0.01) after discharge than at baseline. Multiple regression analysis for baseline data identified five significant predictors of low social support status: workers or farmers ( t =2.82, P <0.01), low family monthly income ( t =2.42, P <0.05), anxiety ( t =-3.66, P <0.01), depression ( t =-3.22, P <0.01) and low quality of life ( t =4.38, P <0.01). Conclusions: Social support of patients with ACS is lower in China, and there are significant relationships between low social support and occupation, economic status, anxiety, depression, quality of life of ACS patients.

Regional projections of the likelihood of very large wildland fires under a changing climate in the contiguous Western United States

Treesearch

Donald McKenzie; John T. Abatzoglou; E. Natasha Stavros; Narasimhan K. Larkin

2014-01-01

Seasonal changes in the climatic potential for very large wildfires (VLWF >= 50,000 ac~20,234 ha) across the western contiguous United States are projected over the 21st century using generalized linear models and downscaled climate projections for two representative concentration pathways (RCPs). Significant (p

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hlond, M.; Bzowski, M.; Moebius, E.

Post-launch boresight of the IBEX-Lo instrument on board the Interstellar Boundary Explorer (IBEX) is determined based on IBEX-Lo Star Sensor observations. Accurate information on the boresight of the neutral gas camera is essential for precise determination of interstellar gas flow parameters. Utilizing spin-phase information from the spacecraft attitude control system (ACS), positions of stars observed by the Star Sensor during two years of IBEX measurements were analyzed and compared with positions obtained from a star catalog. No statistically significant differences were observed beyond those expected from the pre-launch uncertainty in the Star Sensor mounting. Based on the star observations andmore » their positions in the spacecraft reference system, pointing of the IBEX satellite spin axis was determined and compared with the pointing obtained from the ACS. Again, no statistically significant deviations were observed. We conclude that no systematic correction for boresight geometry is needed in the analysis of IBEX-Lo observations to determine neutral interstellar gas flow properties. A stack-up of uncertainties in attitude knowledge shows that the instantaneous IBEX-Lo pointing is determined to within {approx}0.{sup 0}1 in both spin angle and elevation using either the Star Sensor or the ACS. Further, the Star Sensor can be used to independently determine the spacecraft spin axis. Thus, Star Sensor data can be used reliably to correct the spin phase when the Star Tracker (used by the ACS) is disabled by bright objects in its field of view. The Star Sensor can also determine the spin axis during most orbits and thus provides redundancy for the Star Tracker.« less

Effect of monoclonal antibodies (MoAb) to class I and class II HLA antigens on lectin- and MoAb OKT3-induced lymphocyte proliferation.

PubMed

Akiyama, Y; Zicht, R; Ferrone, S; Bonnard, G D; Herberman, R B

1985-04-01

We have examined the effect of several monoclonal antibodies (MoAb) to monomorphic determinants of class II HLA antigens, and MoAb to monomorphic determinants of class I HLA antigens and to beta-2-microglobulin (beta 2-mu) on lectin- and MoAb OKT3-induced proliferation of human peripheral blood mononuclear cells (PBMNC) and cultured T cells (CTC). Some, but not all, anti-class II HLA MoAb inhibited the proliferative response of PBMNC to MoAb OKT3 and pokeweed mitogen (PWM). The degree of inhibitory effect varied considerably. This effect was not limited to anti-class II HLA MoAb since anti-class I HLA MoAb and anti-beta 2-mu MoAb also inhibited MoAb OKT3- or PWM-induced proliferative responses. In contrast, the response of PBMNC to phytohemagglutinin (PHA) and concanavalin A (Con A) was not blocked by any anti-class II HLA MoAb. However, some anti-class II HLA MoAb also inhibited the proliferative response of CTC plus allogeneic peripheral blood adherent accessory cells (AC) to PHA or Con A as well as to MoAb OKT3 or PWM. This may be attributable to the substantially greater class II HLA antigen expression by CTC than by fresh lymphocytes. Pretreatment of either CTC or AC with anti-class II HLA MoAb inhibited OKT3-induced proliferation. In contrast, pretreatment of CTC, but not AC, with anti-class I HLA MoAb inhibited the proliferative response of CTC to OKT3. Pretreatment of CTC with anti-class I HLA MoAb inhibited PHA-, Con A and PWM-induced proliferation, to a greater degree than the anti-class II HLA MoAb. It appears as if lymphocyte activation by different mitogens exhibits variable requirements for the presence of cells expressing major histocompatibility determinants. Binding of Ab to membrane markers may interfere with lymphocyte-AC cooperation, perhaps by inhibiting binding of mitogens to their receptors or by interfering with lymphocyte and AC function. We also have examined the role of class II HLA antigens on CTC by depleting class II HLA-positive cells. As expected, elimination of class II HLA-positive AC with anti-class II HLA MoAb plus complement caused a decrease in proliferation of CTC in response to all the mitogens tested. In contrast, elimination of class II HLA-positive CTC was shown to clearly increase proliferation of CTC, perhaps because this may deplete class II HLA-positive suppressor cells.

Acquisition of Cry1Ac Protein by Non-Target Arthropods in Bt Soybean Fields

PubMed Central

Yu, Huilin; Romeis, Jörg; Li, Yunhe; Li, Xiangju; Wu, Kongming

2014-01-01

Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean. PMID:25110881

A novel electrochemical sensor based on FeS anchored reduced graphene oxide nanosheets for simultaneous determination of dopamine and acetaminophen.

PubMed

Liu, Xiaoya; Shangguan, Enbo; Li, Jing; Ning, Sashuang; Guo, Litan; Li, Quanmin

2017-01-01

In this paper, FeS nanoparticles anchored on reduced graphene oxide (rGO) nanosheets are synthesized via a facile direct-precipitation method. For the first time, a novel electrochemical sensor is developed based on FeS/rGO nanosheets modified glassy carbon electrode (GCE). It has been proved that the resultant FeS/rGO/GCE sensor is very suitable for the individual and simultaneous measurement of dopamine (DA) and acetaminophen (AC) and delivers excellent anti-interference ability to ascorbic acid (AA) and uric acid (UA). Under optimum conditions with differential pulse voltammetry method, a broad linear response versus the concentrations of DA and AC has been observed in the ranges of 2.0 to 250.0μM and 5.0 to 300.0μM, respectively. The detection limits for DA and AC are 0.098μM and 0.18μM, respectively. Furthermore, the as-obtained sensor has been successfully utilized in real samples and satisfactory results have been achieved. Consequently, by virtue of its outstanding electrocatalytic activity, excellent sensitivity, and long time stability, the as-obtained FeS/rGO modified electrode can be considered as a new promising DA and AC sensor. Copyright © 2016. Published by Elsevier B.V.

Solar Dynamic Power System Stability Analysis and Control

NASA Technical Reports Server (NTRS)

Momoh, James A.; Wang, Yanchun

1996-01-01

The objective of this research is to conduct dynamic analysis, control design, and control performance test of solar power system. Solar power system consists of generation system and distribution network system. A bench mark system is used in this research, which includes a generator with excitation system and governor, an ac/dc converter, six DDCU's and forty-eight loads. A detailed model is used for modeling generator. Excitation system is represented by a third order model. DDCU is represented by a seventh order system. The load is modeled by the combination of constant power and constant impedance. Eigen-analysis and eigen-sensitivity analysis are used for system dynamic analysis. The effects of excitation system, governor, ac/dc converter control, and the type of load on system stability are discussed. In order to improve system transient stability, nonlinear ac/dc converter control is introduced. The direct linearization method is used for control design. The dynamic analysis results show that these controls affect system stability in different ways. The parameter coordination of controllers are recommended based on the dynamic analysis. It is concluded from the present studies that system stability is improved by the coordination of control parameters and the nonlinear ac/dc converter control stabilize system oscillation caused by the load change and system fault efficiently.

Electric dipole spin resonance in a quantum spin dimer system driven by magnetoelectric coupling

NASA Astrophysics Data System (ADS)

Kimura, Shojiro; Matsumoto, Masashige; Akaki, Mitsuru; Hagiwara, Masayuki; Kindo, Koichi; Tanaka, Hidekazu

2018-04-01

In this Rapid Communication, we propose a mechanism for electric dipole active spin resonance caused by spin-dependent electric polarization in a quantum spin gapped system. This proposal was successfully confirmed by high-frequency electron spin resonance (ESR) measurements of the quantum spin dimer system KCuCl3. ESR measurements by an illuminating linearly polarized electromagnetic wave reveal that the optical transition between the singlet and triplet states in KCuCl3 is driven by an ac electric field. The selection rule of the observed transition agrees with the calculation by taking into account spin-dependent electric polarization. We suggest that spin-dependent electric polarization is effective in achieving fast control of quantum spins by an ac electric field.

Single channel double-duct liquid metal electrical generator using a magnetohydrodynamic device

DOEpatents

Haaland, C.M.; Deeds, W.E.

1999-07-13

A single channel double-duct liquid metal electrical generator using a magnetohydrodynamic (MHD) device. The single channel device provides useful output AC electric energy. The generator includes a two-cylinder linear-piston engine which drives liquid metal in a single channel looped around one side of the MHD device to form a double-duct contra-flowing liquid metal MHD generator. A flow conduit network and drive mechanism are provided for moving liquid metal with an oscillating flow through a static magnetic field to produce useful AC electric energy at practical voltages and currents. Variable stroke is obtained by controlling the quantity of liquid metal in the channel. High efficiency is obtained over a wide range of frequency and power output. 5 figs.

Single channel double-duct liquid metal electrical generator using a magnetohydrodynamic device

DOEpatents

Haaland, Carsten M.; Deeds, W. Edward

1999-01-01

A single channel double-duct liquid metal electrical generator using a magnetohydrodynamic (MHD) device. The single channel device provides useful output AC electric energy. The generator includes a two-cylinder linear-piston engine which drives liquid metal in a single channel looped around one side of the MHD device to form a double-duct contra-flowing liquid metal MHD generator. A flow conduit network and drive mechanism are provided for moving liquid metal with an oscillating flow through a static magnetic field to produce useful AC electric energy at practical voltages and currents. Variable stroke is obtained by controlling the quantity of liquid metal in the channel. High efficiency is obtained over a wide range of frequency and power output.

Regulation of Renewable Energy Sources to Optimal Power Flow Solutions Using ADMM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall-Anese, Emiliano; Zhang, Yijian; Hong, Mingyi

This paper considers power distribution systems featuring renewable energy sources (RESs), and develops a distributed optimization method to steer the RES output powers to solutions of AC optimal power flow (OPF) problems. The design of the proposed method leverages suitable linear approximations of the AC-power flow equations, and is based on the Alternating Direction Method of Multipliers (ADMM). Convergence of the RES-inverter output powers to solutions of the OPF problem is established under suitable conditions on the stepsize as well as mismatches between the commanded setpoints and actual RES output powers. In a broad sense, the methods and results proposedmore » here are also applicable to other distributed optimization problem setups with ADMM and inexact dual updates.« less

Calcium silicate cement sorbent for H/sub 2/S removal and improved gasification processes. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoo, H.J.; Steinberg, M.

1983-10-01

Based on the studies performed on the agglomerated cement sorbent (ACS) pellet for in-situ desulfurization of gases and for improved gasification, in low and medium Btu fluidized bed coal gasifier (FBG) systems, the following conclusions can be drawn: (1) The pelletization method by a drum pelletizer is a good way of agglomerating large sized (>20 US mesh) ACS pellets having high sorbent performance. (2) The ACS pellets have a sulfur capture capacity of about 60% at 950/sup 0/C, are 100% regenerable, and so not lose reactivity during cyclic use. (3) The rate of sulfidation increases linearly with H/sub 2/S concentrationmore » in the feed gas stream up to 1.0%. (4) The rate of sulfidation first increases with temperature in an Arrhenius fashion in the temperature range of 800/sup 0/C to 1000/sup 0/C and then decreases with further increase in temperatures, giving rise to an optimum sulfidation temperature of about 1000/sup 0/C. (5) The gasification of coal or coal char either with CO/sub 2/ gas or by partial oxidation in a 40 mm ID FBG shows that the gasification efficiency of coal (or coal char) is very much enhanced with the ACS pellets and with Greer limestone over the coal (or coal char) alone. There is, however, not much difference between the ACS pellets and Greer limestone in the degree of enhancement. (6) The gasification of coal by partial oxidation with air to low Btu gas in a 1-inch coal-fired FBG unit shows that in the temperature range of 800/sup 0/ to 900/sup 0/C the efficiency of coal gasification is improved by as much as 40% when ACS pellets are used compared to the use of Greer limestone. At the same time the sulfur removal efficiency is increased from 50 to 65% with Greer limestone to over 95% with the ACS pellets.« less

Is hypercortisolism in anorexia nervosa detectable using hair samples?

PubMed

Ritschel, Franziska; Clas, Sabine; Geisler, Daniel; Haas, Verena; Seidel, Maria; Steding, Julius; Roessner, Veit; Kirschbaum, Clemens; Ehrlich, Stefan

2018-03-01

Anorexia nervosa (AN) is a severe mental disorder accompanied by extensive metabolic and endocrine abnormalities. It has been associated with hypercortisolism using short-term measurement methods such as 24 h-urine, saliva, and blood. The aim of this study was to examine whether the proposed hypercortisolism in acutely underweight AN (acAN) is also reflected in a long-term measure: hair cortisol (HCC). To gain further insight, we compared hair cortisol to a well-established classical cortisol measure (24 h-urine; UCC) longitudinally in acAN. Hair samples were collected and analyzed using a LC-MS/MS-based method to provide a monthly cortisol value. We compared HCC in samples of 40 acAN with 40 pairwise age-matched healthy controls (HC) as well as 23 long-term recovered AN participants (recAN) with 23 pairwise age-matched HC (cross-sectional design). In the second part, UCC collected weekly during 14 weeks of weight-restoration therapy in 16 acAN was compared with the (time-corresponding) HCC using linear mixed models and bivariate correlations (longitudinal design). No group differences in HCC occurred comparing acAN and recAN to HC (cross-sectional study). The longitudinal analysis revealed a decrease of UCC but not HCC with weight gain. Furthermore, there was no overall significant association between UCC and HCC. Only in the last four weeks of weight-restoration therapy we found a significant moderate correlation between UCC and HCC. HCC did not reflect the expected hypercortisolism in acAN and did not decrease during short-term weight-restoration. Time-corresponding measurements of UCC and HCC were not consistently associated in our longitudinal analysis of acAN undergoing inpatient treatment. Given the drastic metabolic disturbances in acutely underweight AN our findings could be interpreted as disturbed cortisol incorporation or altered activity of 11-β-HSD-enzymes in the hair follicle. Copyright © 2017. Published by Elsevier Ltd.

MO-FG-CAMPUS-TeP3-05: Limitations of the Dose Weighted LET Concept for Intensity Modulated Proton Therapy in the Distal Falloff Region and Beyond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moskvin, V; Pirlepesov, F; Farr, J

2016-06-15

Purpose: Dose-weighted linear energy transfer (dLET) has been shown to be useful for the analysis of late effects in proton therapy. This study presents the results of the testing of the dLET concept for intensity modulated proton therapy (IMPT) with a discrete spot scanning beam system without use of an aperture or compensator (AC). Methods: IMPT (no AC) and broad beams (BB) with (AC) were simulated in the TOPAS and FLUKA code systems. Information from the independently tested Monte Carlo Damage Simulation (MCDS) was integrated into the FLUKA code systems to account for spatial variations in the RBE for protonsmore » and other light ions using an endpoint of DNA double strand break (DSB) induction. Results: The proton spectra for IMPT beams at the depths beyond the distal edge contain a tail of high energy protons up to 100 MeV. The integral from the tail is compatible with the number of 5–8 MeV protons at the tip of the Bragg peak (BP). The dose averaged energy (dEav) decreases to 7 MeV at the tip of (BP) and then increases to about 15 MeV beyond the distal edge. Neutrons produced in the nozzle are two orders of magnitude higher for BB with AC than for IMPT in low energy part of the spectra. The dLET values beyond of the distal edge of the BP are 5 times larger for the IMPT than for BB with the AC. Contrarily, negligible differences are seen in the RBE estimates for IMPT and BB with AC beyond the distal edge of the BP. Conclusion: The analysis of late effects in IMPT with a spot scanning and double scattering or scanning techniques with AC may requires both dLET and RBE as quantitative parameters to characterize effects beyond the distal edge of the BP.« less

Estimating the strength of bone using linear response

NASA Astrophysics Data System (ADS)

Gunaratne, Gemunu H.

2002-12-01

Accurate diagnostic tools are required for effective management of osteoporosis; one method to identify additional diagnostics is to search for observable consequences of bone loss. An analysis of a model system is used to show that weakening of a bone is accompanied by a reduction of the fraction of the bone that participates in load transmission. On the basis of this observation, it is argued that the ratio Γ of linear responses of a network to dc and high-frequency ac driving can be used as a surrogate for their strength. Protocols needed to obtain Γ for bone samples are discussed.

Positive expiratory pressure device acceptance by hospitalized children with sickle cell disease is comparable to incentive spirometry.

PubMed

Hsu, Lewis L; Batts, Brenda K; Rau, Joseph L

2005-05-01

The pulmonary complication in sickle cell disease known as acute chest syndrome (ACS) has potential for high morbidity and mortality. A randomized trial demonstrated that incentive spirometry (IS) reduces the rate of ACS, leading to a role for respiratory therapy in hospital management of sickle cell pain. However, use of IS can be limited by chest wall pain, or by difficulty with the coordinated inspiration in a young child. Intermittent positive expiratory pressure (PEP) therapy may be easier for a child's coordination and more comfortable than IS for a child with chest wall pain. To compare PEP therapy with conventional IS for children hospitalized for sickle cell pain with respect to patient satisfaction, length of hospital stay, and progression to ACS. This pilot study enrolled 20 children upon hospitalization for sickle cell pain in the thorax, randomly assigning them to either PEP (n = 11) or IS (n = 9) therapy, administered by a therapist hourly while awake. The randomization assigned an older distribution to PEP than IS (12.3 vs 8.8 y). Patient satisfaction was high for both respiratory care devices, and there was no difference between the PEP and IS groups (4.5 vs 4.4, p = 0.81). Length of hospital stay was similar (5 vs 4.3 d, p = 0.56). No children in either group progressed to ACS. These preliminary results show no difference in the primary outcomes in the 2 groups. Intermittent PEP therapy warrants further study as an alternative to IS for sickle cell patients at high risk for ACS, as effective preventive respiratory therapy.

Assessment on the influence of resistive superconducting fault current limiter in VSC-HVDC system

NASA Astrophysics Data System (ADS)

Lee, Jong-Geon; Khan, Umer Amir; Hwang, Jae-Sang; Seong, Jae-Kyu; Shin, Woo-Ju; Park, Byung-Bae; Lee, Bang-Wook

2014-09-01

Due to fewer risk of commutation failures, harmonic occurrences and reactive power consumptions, Voltage Source Converter (VSC) based HVDC system is known as the optimum solution of HVDC power system for the future power grid. However, the absence of suitable fault protection devices for HVDC system hinders the efficient VSC-HVDC power grid design. In order to enhance the reliability of the VSC-HVDC power grid against the fault current problems, the application of resistive Superconducting Fault Current Limiters (SFCLs) could be considered. Also, SFCLs could be applied to the VSC-HVDC system with integrated AC Power Systems in order to enhance the transient response and the robustness of the system. In this paper, in order to evaluate the role of SFCLs in VSC-HVDC systems and to determine the suitable position of SFCLs in VSC-HVDC power systems integrated with AC power System, a simulation model based on Korea Jeju-Haenam HVDC power system was designed in Matlab Simulink/SimPowerSystems. This designed model was composed of VSC-HVDC system connected with an AC microgrid. Utilizing the designed VSC-HVDC systems, the feasible locations of resistive SFCLs were evaluated when DC line-to-line, DC line-to-ground and three phase AC faults were occurred. Consequently, it was found that the simulation model was effective to evaluate the positive effects of resistive SFCLs for the effective suppression of fault currents in VSC-HVDC systems as well as in integrated AC Systems. Finally, the optimum locations of SFCLs in VSC-HVDC transmission systems were suggested based on the simulation results.

Cognitive demands and the relationship between age and workload in apron control.

PubMed

Müller, Andreas; Petru, Raluca; Angerer, Peter

2011-01-01

Apron controllers (ACs) determine the taxiways for aircraft entering the apron area until they reach their parking positions and vice versa. The aims of this study were to identify age-sensitive job requirements of apron control (Study 1), and to investigate the relationship between age of ACs and their workload (Study 2). Study 1: There were 14 experienced ACs who assessed the job requirements of apron control with the Fleishman-Job Analyses Survey. Additionally, during one shift, the number of parallel processed traffic data sets (indicating memory-load) and the number of delivered radio messages (indicating processing speed requirements) were assessed. Study 2: There were 30 ACs (age: 23-51 yr) who volunteered for trials during late shifts at an international airport. ACs assessed their subjective workload (NASA-Task Load Index) at four times during the shift and carried out an attention test (d2) before and after the shift. Moreover, their heart rate was assessed during the shift and in a reference period. Study 1: Results indicate that apron control requires especially high levels of memory-load and processing speed. Study 2: Hierarchical regression analyses revealed a u-shaped relationship between age and subjective workload (beta = 0.59) as well as heart rate (beta = 0.33). Up to the age of about 35-37 yr, workload and heart rate decreased with age, but afterwards the relationship became positive. There was no association between chronological age and attention performance. There is a need for age adequate job design in apron control that should especially aim at the reduction of memory-load and processing speed.

The effect of temperature and ration size on the growth, body composition, and energy content of juvenile coho salmon

USGS Publications Warehouse

Edsall, Thomas A.; Frank, Anthony M.; Rottiers, Donald V.; Adams, Jean V.

1999-01-01

Juvenile (postsmolt) coho salmon (Oncorhynchus kitsuch) were held in fresh water in the laboratory at 5, 10, 15, and 18A?C for 8 weeks and fed freshly thawed, juvenile alewives (Alosa pseudoharengus) at rates equal to 1 and 2 % of their wet body weight/day, and also at the ad libitum or unrestricted ration rate. Most rapid growth in weight (1.2% wet body weight/day) occurred among fish fed the ad libitum ration at 15A?C; growth was most rapid at about 10A?C for fish fed the 2% ration (0.7%/day), and the 1% ration (0.1%/day). Gross conversion efficiency was highest at 10A?C for all three ration levels. Gross body constituents and energy content of the test fish changed with temperature and ration during the study. Growth rate was positively related to lipid, energy content, and ration; lipid and energy content were positively related to water temperature; lipid, energy content, growth rate, ration, and water temperature were negatively related to water content; and protein was not related to any of the test variables. At the end of the study, water (68.7 to 76.4%) and lipid (3.5 to 10.4%) content were more variable than ash (1.8 to 3.1%), carbohydrate (0.1 to 1.9%), and protein (16.9 to 19.4%) content. Energy content of the fish increased with ration and was highest for each ration level at 15A?C.

The "Acute coronary syndromes: consensus recommendations for translating knowledge into action" position statement is based on a false premise.

PubMed

Forge, Brett H

2010-06-21

Recent National Heart Foundation of Australia (NHFA) guidelines for management of acute coronary syndromes (ACS) recommend increasing the rates of early invasive management of ACS and providing equal access for all Australians to percutaneous coronary intervention (PCI) facilities. For patients with ACS managed in regional hospitals without PCI facilities, review of the evidence does not show unequivocal benefit of early routine PCI over selective PCI for patients with non-ST-segment-elevation ACS or ST-elevation myocardial infarction. The current pattern of transfer based on the NHFA guidelines is expensive and disruptive of patient care, as well as undermining regional health care services. Further increase in transfer rates and increases in PCI facilities would divert resources away from supporting the regional infrastructure needed to provide evidence-based therapies, without any evidence that lives would be saved.

Development of an Integrated Chip for Automatic Tracking and Positioning Manipulation for Single Cell Lysis

PubMed Central

Young, Chao-Wang; Hsieh, Jia-Ling; Ay, Chyung

2012-01-01

This study adopted a microelectromechanical fabrication process to design a chip integrated with electroosmotic flow and dielectrophoresis force for single cell lysis. Human histiocytic lymphoma U937 cells were driven rapidly by electroosmotic flow and precisely moved to a specific area for cell lysis. By varying the frequency of AC power, 15 V AC at 1 MHz of frequency configuration achieved 100% cell lysing at the specific area. The integrated chip could successfully manipulate single cells to a specific position and lysis. The overall successful rate of cell tracking, positioning, and cell lysis is 80%. The average speed of cell driving was 17.74 μm/s. This technique will be developed for DNA extraction in biomolecular detection. It can simplify pre-treatment procedures for biotechnological analysis of samples. PMID:22736957

Development of an integrated chip for automatic tracking and positioning manipulation for single cell lysis.

PubMed

Young, Chao-Wang; Hsieh, Jia-Ling; Ay, Chyung

2012-01-01

This study adopted a microelectromechanical fabrication process to design a chip integrated with electroosmotic flow and dielectrophoresis force for single cell lysis. Human histiocytic lymphoma U937 cells were driven rapidly by electroosmotic flow and precisely moved to a specific area for cell lysis. By varying the frequency of AC power, 15 V AC at 1 MHz of frequency configuration achieved 100% cell lysing at the specific area. The integrated chip could successfully manipulate single cells to a specific position and lysis. The overall successful rate of cell tracking, positioning, and cell lysis is 80%. The average speed of cell driving was 17.74 μm/s. This technique will be developed for DNA extraction in biomolecular detection. It can simplify pre-treatment procedures for biotechnological analysis of samples.

Allergic colitis in infants related to cow's milk: clinical characteristics, pathologic changes, and immunologic findings.

PubMed

Yu, Man-Chun; Tsai, Chia-Lun; Yang, Yao-Jong; Yang, Sing-San; Wang, Li-Hui; Lee, Chung-Ta; Jan, Ren-Long; Wang, Jiu-Yao

2013-02-01

Allergic colitis (AC) is an inflammatory condition characterized by eosinophils infiltrating the colonic wall. It can be a benign and/or severe illness among gastrointestinal diseases in infants. We report five infants who, since January 2009, in whom AC under fibrotic endoscopic examinations has been diagnosed. The criterion for histopathologic diagnosis of AC in this study was five or more eosinophils per high-power field. Patients' clinical symptoms, pathologic findings, and immunologic studies, such as specific antibodies against component of cow's milk protein, were compared with those of allergic children without AC and those of nonatopic control children. Histopathologic examinations of biopsy specimens revealed acute inflammation with characteristic eosinophilic infiltration of lamina propria (5-15 eosinophils per high-power field) in all five patients. They all had strongly positive skin prick tests against milk protein, which were not correlated with in vitro allergen-specific immunoglobulin (Ig) E levels. In contrast, there were significantly higher levels of IgE antibodies, and lower specific IgG4 and IgA levels to components and whole milk proteins in AC, as compared to control children without AC. Endoscopic biopsy specimens of intestine confirm the diagnosis of AC. However, allergen skin prick test and IgE antibody to milk protein components also provide helpful diagnostic tools for this rare disease in children. Copyright © 2012. Published by Elsevier B.V.

78 FR 79338 - Airworthiness Directives; Bombardier, Inc. Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-30

...We propose to adopt a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400 series airplanes. This proposed AD was prompted by reports of missing clamps that are required to provide positive separation between the alternating current (AC) feeder cables and the hydraulic line of the landing gear alternate extension. This proposed AD would require inspecting for missing clamps, and related investigative and corrective actions if necessary. We are proposing this AD to detect and correct chafing of the AC feeder cable. A chafed and arcing AC feeder cable could puncture the adjacent hydraulic line, which, in combination with the use of the alternate extension system, could result in an in-flight fire.

Driving Human Motor Cortical Oscillations Leads to Behaviorally Relevant Changes in Local GABAA Inhibition: A tACS-TMS Study

PubMed Central

van Ede, Freek

2017-01-01

Beta and gamma oscillations are the dominant oscillatory activity in the human motor cortex (M1). However, their physiological basis and precise functional significance remain poorly understood. Here, we used transcranial magnetic stimulation (TMS) to examine the physiological basis and behavioral relevance of driving beta and gamma oscillatory activity in the human M1 using transcranial alternating current stimulation (tACS). tACS was applied using a sham-controlled crossover design at individualized intensity for 20 min and TMS was performed at rest (before, during, and after tACS) and during movement preparation (before and after tACS). We demonstrated that driving gamma frequency oscillations using tACS led to a significant, duration-dependent decrease in local resting-state GABAA inhibition, as quantified by short interval intracortical inhibition. The magnitude of this effect was positively correlated with the magnitude of GABAA decrease during movement preparation, when gamma activity in motor circuitry is known to increase. In addition, gamma tACS-induced change in GABAA inhibition was closely related to performance in a motor learning task such that subjects who demonstrated a greater increase in GABAA inhibition also showed faster short-term learning. The findings presented here contribute to our understanding of the neurophysiological basis of motor rhythms and suggest that tACS may have similar physiological effects to endogenously driven local oscillatory activity. Moreover, the ability to modulate local interneuronal circuits by tACS in a behaviorally relevant manner provides a basis for tACS as a putative therapeutic intervention. SIGNIFICANCE STATEMENT Gamma oscillations have a vital role in motor control. Using a combined tACS-TMS approach, we demonstrate that driving gamma frequency oscillations modulates GABAA inhibition in the human motor cortex. Moreover, there is a clear relationship between the change in magnitude of GABAA inhibition induced by tACS and the magnitude of GABAA inhibition observed during task-related synchronization of oscillations in inhibitory interneuronal circuits, supporting the hypothesis that tACS engages endogenous oscillatory circuits. We also show that an individual's physiological response to tACS is closely related to their ability to learn a motor task. These findings contribute to our understanding of the neurophysiological basis of motor rhythms and their behavioral relevance and offer the possibility of developing tACS as a therapeutic tool. PMID:28348136

An examination of the psychometric properties of the Rosenberg Self-Esteem Scale (RSES) in Chinese acute coronary syndrome (ACS) patients.

PubMed

Martin, Colin R; Thompson, David R; Chan, Dominic S

2006-11-01

The psychometric properties of the Rosenberg Self-Esteem Scale (RSES) as a clinical research instrument for acute coronary syndrome (ACS) patients were investigated in a translated Chinese version of the instrument. A confirmatory factor analysis was conducted on the RSES to establish its psychometric properties in 128 ACS patients over two observation points (within 1 week and 6 months post-admission for ACS). Internal and test-retest reliability of the RSES-TOT (all-items) and RSES-POS sub-scale (positively valenced items) were found to be acceptable. The RSES-NEG sub-scale (negatively valenced items) lacked acceptable internal reliability. The underlying factor structure of the RSES comprised two distinct but related factors, though there was inconsistency in best model fit indices at the 1-week observation point. The use of the RSES as two sub-scales (RSES-POS and RSES-NEG) may be clinically useful in evaluating the influence of this important psychological construct on the health outcomes of patients with ACS. Directions for future research are indicated.

High accuracy-nationwide differential global positioning system test and analysis : phase II report

DOT National Transportation Integrated Search

2005-07-01

The High Accuracy-Nationwide Differential Global Positioning System (HA-NDGPS) program focused on the development of compression and broadcast techniques to provide users over a large area wit very accurate radio navigation solutions. The goal was ac...

Arthroscopic treatment of acute acromioclavicular joint dislocation by coracoclavicular ligament augmentation.

PubMed

Liu, Xudong; Huangfu, Xiaoqiao; Zhao, Jinzhong

2015-05-01

Coracoclavicular (CC) ligament augmentation has been a method to treat acromioclavicular (AC) joint dislocation in recent years. The purpose of this paper is to describe our arthroscopic CC ligament augmentation technique in treating type III and V acute AC joint dislocations and to report the early clinical and radiological results. From 2010 to 2011, twelve patients suffering from acute type III or V AC joint dislocations were arthroscopically treated in our department, by CC ligament augmentation after AC joint reduction. The post-operative outcomes were assessed through physical examination, radiographic examination and the Constant-Murley Shoulder Score. All patients post-operatively experienced anatomical reduction in their AC joint dislocation. No intraoperative complications occurred. At a mean follow-up at 24 months (ranging from 18 to 32 months), the mean Constant-Murley Shoulder Score significantly improved from 24.3 pre-operatively to 91.1 post-operatively. No neurovascular complications or secondary degenerative changes of the AC joint were detected in any of the patients. In one case, a second dislocation occurred 1 month post-operation because the patient had had another traumatic injury. This patient accepted a revision operation, but his AC joint eventually fixated into a subluxated position after his second injury. Based on the resultant successful repair in all cases, the arthroscopic CC ligament augmentation method has thus far proven to be a safe and reliable technique for treatment of acute type III or V AC joint dislocation. The arthroscopic CC ligament augmentation with a flip button/polyethylene belt repair is an efficient method to treat acute type III and V AC joint dislocations which should be popularized. IV.

Genome-wide profiling identifies a subset of methamphetamine (METH)-induced genes associated with METH-induced increased H4K5Ac binding in the rat striatum

PubMed Central

2013-01-01

Background METH is an illicit drug of abuse that influences gene expression in the rat striatum. Histone modifications regulate gene transcription. Methods We therefore used microarray analysis and genome-scale approaches to examine potential relationships between the effects of METH on gene expression and on DNA binding of histone H4 acetylated at lysine 4 (H4K5Ac) in the rat dorsal striatum of METH-naïve and METH-pretreated rats. Results Acute and chronic METH administration caused differential changes in striatal gene expression. METH also increased H4K5Ac binding around the transcriptional start sites (TSSs) of genes in the rat striatum. In order to relate gene expression to histone acetylation, we binned genes of similar expression into groups of 100 genes and proceeded to relate gene expression to H4K5Ac binding. We found a positive correlation between gene expression and H4K5Ac binding in the striatum of control rats. Similar correlations were observed in METH-treated rats. Genes that showed acute METH-induced increased expression in saline-pretreated rats also showed METH-induced increased H4K5Ac binding. The acute METH injection caused similar increases in H4K5Ac binding in METH-pretreated rats, without affecting gene expression to the same degree. Finally, genes that showed METH-induced decreased expression exhibited either decreases or no changes in H4K5Ac binding. Conclusion Acute METH injections caused increased gene expression of genes that showed increased H4K5Ac binding near their transcription start sites. PMID:23937714

Genome-wide profiling identifies a subset of methamphetamine (METH)-induced genes associated with METH-induced increased H4K5Ac binding in the rat striatum.

PubMed

Cadet, Jean Lud; Jayanthi, Subramaniam; McCoy, Michael T; Ladenheim, Bruce; Saint-Preux, Fabienne; Lehrmann, Elin; De, Supriyo; Becker, Kevin G; Brannock, Christie

2013-08-12

METH is an illicit drug of abuse that influences gene expression in the rat striatum. Histone modifications regulate gene transcription. We therefore used microarray analysis and genome-scale approaches to examine potential relationships between the effects of METH on gene expression and on DNA binding of histone H4 acetylated at lysine 4 (H4K5Ac) in the rat dorsal striatum of METH-naïve and METH-pretreated rats. Acute and chronic METH administration caused differential changes in striatal gene expression. METH also increased H4K5Ac binding around the transcriptional start sites (TSSs) of genes in the rat striatum. In order to relate gene expression to histone acetylation, we binned genes of similar expression into groups of 100 genes and proceeded to relate gene expression to H4K5Ac binding. We found a positive correlation between gene expression and H4K5Ac binding in the striatum of control rats. Similar correlations were observed in METH-treated rats. Genes that showed acute METH-induced increased expression in saline-pretreated rats also showed METH-induced increased H4K5Ac binding. The acute METH injection caused similar increases in H4K5Ac binding in METH-pretreated rats, without affecting gene expression to the same degree. Finally, genes that showed METH-induced decreased expression exhibited either decreases or no changes in H4K5Ac binding. Acute METH injections caused increased gene expression of genes that showed increased H4K5Ac binding near their transcription start sites.

A role for calmodulin-stimulated adenylyl cyclases in cocaine sensitization.

PubMed

DiRocco, Derek P; Scheiner, Zachary S; Sindreu, Carlos Balet; Chan, Guy C-K; Storm, Daniel R

2009-02-25

Cocaine sensitization is produced by repeated exposure to the drug and is thought to reflect neuroadaptations that contribute to addiction. Here, we identify the Ca(2+)/calmodulin-stimulated adenylyl cyclases, type 1 (AC1) and type 8 (AC8), as novel regulators of this behavioral plasticity. We show that, whereas AC1 and AC8 single knock-out mice (AC1(-/-) and AC8(-/-)) exhibit Ca(2+)-stimulated adenylyl cyclase activity in striatal membrane fractions, AC1/8 double-knock-out (DKO) mice do not. Furthermore, DKO mice are acutely supersensitive to low doses of cocaine and fail to display locomotor sensitization after chronic cocaine treatment. Because of the known role for the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase signaling pathway in cocaine-induced behavioral plasticity and its coupling to calcium-stimulated cAMP signaling in the hippocampus, we measured phosphorylated ERK (pERK) levels in the striatum. Under basal conditions, pERK is upregulated in choline acetyltransferase-positive interneurons in DKO mice relative to wild-type (WT) controls. After acute cocaine treatment, pERK signaling is significantly suppressed in medium spiny neurons (MSNs) of DKO mice relative to WT mice. In addition to the lack of striatal ERK activation by acute cocaine, signaling machinery downstream of ERK is uncoupled in DKO mice. We demonstrate that AC1 and AC8 are necessary for the phosphorylation of mitogen and stress-activated kinase-1 (pMSK1) at Ser376 and Thr581 and cAMP response element-binding protein (pCREB) at Ser133 after acute cocaine treatment. Our results demonstrate that the Ca(2+)-stimulated adenylyl cyclases regulate long-lasting cocaine-induced behavioral plasticity via activation of the ERK/MSK1/CREB signaling pathway in striatonigral MSNs.

A Role for Calmodulin-Stimulated Adenylyl Cyclases in Cocaine Sensitization

PubMed Central

DiRocco, Derek P.; Scheiner, Zachary S.; Sindreu, Carlos Balet; Chan, Guy C-K; Storm, Daniel R.

2009-01-01

Cocaine sensitization is produced by repeated exposure to the drug and is thought to reflect neuroadaptations that contribute to addiction. Here, we identify the Ca2+/calmodulin-stimulated adenylyl cyclases, type 1 (AC1) and type 8 (AC8), as novel regulators of this behavioral plasticity. We show that while AC1 and AC8 single knockout mice (AC1−/− and AC8−/−) exhibit Ca2+-stimulated adenylyl cyclase activity in striatal membrane fractions, AC1/8 double-knockout (DKO) mice do not. Furthermore, DKO mice are acutely supersensitive to low doses of cocaine and fail to display locomotor sensitization following chronic cocaine treatment. Because of the known role for the ERK/MAP kinase signaling pathway in cocaine-induced behavioral plasticity and its coupling to calcium-stimulated cAMP signaling in the hippocampus, we measured phosphorylated extracellular signal-regulated kinase (pERK) levels in the striatum. Under basal conditions, pERK is upregulated in choline acetyltransferase positive (ChAT+) interneurons in DKO mice relative to wild-type (WT) controls. Following acute cocaine treatment, pERK signaling is significantly suppressed in medium spiny neurons (MSNs) of DKO mice relative to WT mice. In addition to the lack of striatal ERK activation by acute cocaine, signaling machinery downstream of ERK is uncoupled in DKO mice. We demonstrate that AC1 and AC8 are necessary for the phosphorylation of mitogen and stress-activated kinase-1 (pMSK1) at Ser376 and Thr581, and cAMP response element-binding protein (pCREB) at Ser133 following acute cocaine treatment. Our results demonstrate that the Ca2+-stimulated adenylyl cyclases regulate long-lasting cocaine-induced behavioral plasticity via activation of the ERK/MSK1/CREB signaling pathway in striatonigral MSNs. PMID:19244515

ENSO and East Asian winter monsoon relationship modulation associated with the anomalous northwest Pacific anticyclone

NASA Astrophysics Data System (ADS)

Kim, Ji-Won; An, Soon-Il; Jun, Sang-Yoon; Park, Hey-Jin; Yeh, Sang-Wook

2017-08-01

Using observational datasets and numerical model experiments, the mechanism on the slowly varying change in the relationship between the El Niño-Southern Oscillation (ENSO) and the East Asian winter monsoon (EAWM) is investigated. The decadal-window (11-, 15-, and 21-year) moving correlations show a significant change in the boreal wintertime ENSO-EAWM relationship between two sub-periods of 1976‒1992 and 1997‒2013. Such recent change in ENSO-EAWM relationship is mainly attributed to the changes in the intensity and zonal location of the anomalous lower-tropospheric northwest Pacific anticyclone (NWP-AC). NWP-AC commonly develops near the region of the Philippine Sea during the ENSO's peak phase and plays an important role of bridging the tropical convection and mid-latitude teleconnection. On one hand, the intensity of the NWP-AC is influenced by the interdecadal variation in a linkage between ENSO and the Indian Ocean sea surface temperature (SST) variability, referring that a strong connection between the Pacific and Indian Oceans results in the strengthening of NWP-AC response to ENSO. On the other hand, the zonal displacement of the NWP-AC is associated with the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO). That is, the tropical Pacific mean state (i.e., zonal SST gradient between climatologically warm western Pacific and cold eastern Pacific)—strengthened by either the negative PDO phase or the positive AMO phase—drives the anomalous ENSO-induced convection to be shifted to the west. With this westward shift, the zonal center of the NWP-AC also migrates westward over the Philippine Islands and exerts stronger connection between ENSO and EAWM. In contrast, the relaxed zonal SST contrast associated with either the positive PDO phase or the negative AMO phase tends to exhibit weaker ENSO-EAWM relationship via both of eastward shifted zonal centers of the anomalous ENSO-induced convection and the NWP-AC. Finally, a series of the numerical experiments conducted by an atmospheric general circulation model supports the observational findings.

Adaptive Harmonic Detection Control of Grid Interfaced Solar Photovoltaic Energy System with Power Quality Improvement

NASA Astrophysics Data System (ADS)

Singh, B.; Goel, S.

2015-03-01

This paper presents a grid interfaced solar photovoltaic (SPV) energy system with a novel adaptive harmonic detection control for power quality improvement at ac mains under balanced as well as unbalanced and distorted supply conditions. The SPV energy system is capable of compensation of linear and nonlinear loads with the objectives of load balancing, harmonics elimination, power factor correction and terminal voltage regulation. The proposed control increases the utilization of PV infrastructure and brings down its effective cost due to its other benefits. The adaptive harmonic detection control algorithm is used to detect the fundamental active power component of load currents which are subsequently used for reference source currents estimation. An instantaneous symmetrical component theory is used to obtain instantaneous positive sequence point of common coupling (PCC) voltages which are used to derive inphase and quadrature phase voltage templates. The proposed grid interfaced PV energy system is modelled and simulated in MATLAB Simulink and its performance is verified under various operating conditions.

HPV prevalence and type-distribution in cervical cancer and premalignant lesions of the cervix: A population-based study from Northern Ireland.

PubMed

Anderson, Lesley A; O'Rorke, Michael A; Wilson, Robbie; Jamison, Jackie; Gavin, Anna T

2016-07-01

Assessment of Human papillomavirus (HPV) prevalence and genotype distribution is important for monitoring the impact of prophylactic HPV vaccination. This study aimed to demonstrate the HPV genotypes predominating in pre-malignant and cervical cancers in Northern Ireland (NI) before the vaccination campaign has effect. Formalin fixed paraffin embedded tissue blocks from 2,303 women aged 16-93 years throughout NI were collated between April 2011 and February 2013. HPV DNA was amplified by PCR and HPV genotyping undertaken using the Roche(®) linear array detection kit. In total, 1,241 out of 1,830 eligible samples (68.0%) tested positive for HPV, with the majority of these [1,181/1,830 (64.5%)] having high-risk (HR) HPV infection; 37.4% were positive for HPV-16 (n = 684) and 5.1% for HPV-18 (n = 93). HPV type-specific prevalence was 48.1%, 65.9%, 81.3%, 92.2%, and 64.3% among cervical intraepithelial neoplasias (CIN) Grades I-III, squamous cell carcinomas (SCC) and adenocarcinoma (AC) cases, respectively. Most SCC cases (81.3%) had only one HPV genotype detected and almost a third (32.0%) of all cervical pathologies were HPV negative including 51.9% of CIN I (n = 283), 34.1% CIN II (n = 145), 18.7% of CIN III (n = 146), 7.8% of SCC (n = 5), and 35.7% of AC (n = 5) cases. This study provides important baseline data for monitoring the effect of HPV vaccination in NI and for comparison with other UK regions. The coverage of other HR-HPV genotypes apart from 16 and 18, including HPV-45, 31, 39, and 52, and the potential for cross protection, should be considered when considering future polyvalent vaccines. © 2015 Wiley Periodicals, Inc.

Comparison of the HEART and TIMI Risk Scores for Suspected Acute Coronary Syndrome in the Emergency Department.

PubMed

Sun, Benjamin C; Laurie, Amber; Fu, Rongwei; Ferencik, Maros; Shapiro, Michael; Lindsell, Christopher J; Diercks, Deborah; Hoekstra, James W; Hollander, Judd E; Kirk, J Douglas; Peacock, W Frank; Anantharaman, Venkataraman; Pollack, Charles V

2016-03-01

The emergency department evaluation for suspected acute coronary syndrome (ACS) is common, costly, and challenging. Risk scores may help standardize clinical care and screening for research studies. The Thrombolysis in Myocardial Infarction (TIMI) and HEART are two commonly cited risk scores. We tested the null hypothesis that the TIMI and HEART risk scores have equivalent test characteristics. We analyzed data from the Internet Tracking Registry of Acute Coronary Syndromes (i*trACS) from 9 EDs on patients with suspected ACS, 1999-2001. We excluded patients with an emergency department diagnosis consistent with ACS, or without sufficient data to calculate TIMI and HEART scores. The primary outcome was 30-day major adverse cardiovascular events, including all-cause death, acute myocardial infarction, and urgent revascularization. We describe test characteristics of the TIMI and HEART risk scores. The study cohort included 8255 patients with 508 (6.2%) 30-day major adverse cardiovascular events. Receiver operating curve and reclassification analyses favored HEART [c statistic: 0.753, 95% confidence interval (CI): 0.733-0.773; continuous net reclassification improvement: 0.608, 95% CI: 0.527-0.689] over TIMI (c statistic: 0.678, 95% CI: 0.655-0.702). A HEART score 0-3 [negative predictive value (NPV) 0.982, 95% CI: 0.978-0.986; positive predictive value (PPV) 0.103, 95% CI: 0.094-0.113; likelihood ratio (LR) positive 1.76; LR negative 0.28] demonstrates similar or superior NPV/PPV/LR compared with TIMI = 0 (NPV 0.978, 95% CI: 0.971-0.983; PPV 0.077, 95% CI: 0.071-0.084; LR positive 1.28; LR negative 0.35) and TIMI = 0-1 (NPV 0.963, 95% CI: 0.958-0.968; PPV 0.102, 95% CI: 0.092-0.113; LR positive 1.73; LR negative 0.58). The HEART score has better discrimination than TIMI and outperforms TIMI within previously published "low-risk" categories.

Investigations of Turbulent Transport Channels in Gyrokinetic Simulations

NASA Astrophysics Data System (ADS)

Dimits, A. M.; Candy, J.; Guttenfelder, W.; Holland, C.; Howard, N.; Nevins, W. M.; Wang, E.

2014-10-01

Magnetic-field stochasticity arises due to microtearing perturbations, which can be driven linearly or nonlinearly (in cases where they are linearly stable), even at very modest values of the plasma beta. The resulting magnetic-flutter contribution may or may not be a significant component of the overall electron (particle and thermal) transport. Investigations of the effect of ExB flow shear on electron-drift magnetic-flutter diffusion coefficient Dedr (r ,v||) using perturbed magnetic fields from simulations, using the GYRO code, of ITG turbulence show a significant effect for electrons with parallel velocities v|| surprisingly far from the resonant velocity. We further examine changes in the radial dependence of this diffusion coefficient vs. v|| and which resonant magnetic-field perturbations are important to the values and radial structure of Dedr. The resulting electron transport fluxes are compared with the simulation results. Improvements over in treating the ambipolar field in the relationship between the magnetic (or drift) diffusion coefficients and the transport have been made in these comparisons. Prepared for US DOE by LLNL under Contract DE-AC52-07NA27344, by GA under Contract DE-FG03-95ER54309, and by PPPL under Contract DE-AC02-09CH11466.

A Multilevel Structural Equation Model of Within- and Between-Person Associations among Subjective Responses to Alcohol, Craving, and Laboratory Alcohol Self-Administration

PubMed Central

Wardell, Jeffrey D.; Ramchandani, Vijay A.; Hendershot, Christian S.

2017-01-01

Subjective responses to alcohol are important determinants of drinking behavior and have been linked with risk for alcohol use disorders. However, few attempts have been made to examine proximal within-person associations among state changes in subjective responses and ongoing alcohol self-administration in the laboratory. This study disaggregated within- and between-person associations among subjective responses and alcohol self-administration, while also examining the mediating role of craving and the moderating role of trait impaired control over alcohol. Sixty young heavy drinkers (mean age=19.90, SD=0.86) completed self-report measures including the Impaired Control Scale, then participated in a 2-hour intravenous alcohol self-administration session using the Computer-Assisted Self-infusion of Ethanol (CASE) paradigm. Repeated assessments of subjective stimulation, subjective sedation, and craving were examined in relation to ongoing in-session self-administration, as indexed by breath alcohol concentration (BrAC) assessed 15 minutes later. Multilevel structural equation modeling was used to disentangle within-person and between-person associations. The results showed few significant associations at the between-person level, except for a direct negative association between sedation and BrAC. At the within-person level, state fluctuations in stimulation were positively associated with both craving and subsequent BrAC, whereas state changes in sedation were negatively associated with craving and positively associated with BrAC. Within-person indirect associations from subjective stimulation and sedation to subsequent BrAC mediated via craving were statistically significant. Also, participants higher on impaired control showed stronger within-person associations between craving and greater subsequent BrAC. The results suggest that subjective responses to alcohol and craving have proximal associations with self-administration behavior, the strength of which is linked with trait impaired control over alcohol. PMID:26595481

Negative urgency and ventromedial prefrontal cortex responses to alcohol cues: FMRI evidence of emotion-based impulsivity.

PubMed

Cyders, Melissa A; Dzemidzic, Mario; Eiler, William J; Coskunpinar, Ayca; Karyadi, Kenny; Kareken, David A

2014-02-01

Recent research has highlighted the role of emotion-based impulsivity (negative and positive urgency personality traits) for alcohol use and abuse, but has yet to examine how these personality traits interact with the brain's motivational systems. Using functional magnetic resonance imaging (fMRI), we tested whether urgency traits and mood induction affected medial prefrontal responses to alcohol odors (AcO). Twenty-seven social drinkers (mean age = 25.2, 14 males) had 6 fMRI scans while viewing negative, neutral, or positive mood images (3 mood conditions) during intermittent exposure to AcO and appetitive control (AppCo) aromas. Voxel-wise analyses (p < 0.001) confirmed [AcO > AppCo] activation throughout medial prefrontal cortex (mPFC) and ventromedial PFC (vmPFC) regions. Extracted from a priori mPFC and vmPFC regions and analyzed in Odor (AcO, AppCo) × Mood factorial models, AcO activation was greater than AppCo in left vmPFC (p < 0.001), left mPFC (p = 0.002), and right vmPFC (p = 0.01) regions. Mood did not interact significantly with activation, but the covariate of trait negative urgency accounted for significant variance in left vmPFC (p = 0.01) and right vmPFC (p = 0.01) [AcO > AppCo] activation. Negative urgency also mediated the relationship between vmPFC activation and both (i) subjective craving and (ii) problematic drinking. The trait of negative urgency is associated with neural responses to alcohol cues in the vmPFC, a region involved in reward value and emotion-guided decision-making. This suggests that negative urgency might alter subjective craving and brain regions involved in coding reward value. Copyright © 2013 by the Research Society on Alcoholism.

A field-based community assessment of intoxication levels across college football weekends: does it matter who's playing?

PubMed

Barry, Adam E; Howell, Steve; Bopp, Trevor; Stellefson, Michael; Chaney, Elizabeth; Piazza-Gardner, Anna; Payne-Purvis, Caroline

2014-12-01

While alcohol consumption has been consistently linked to college football games in the United States, this literature lacks (a) field-based event-level analyses; (b) assessments of the context of drinking, such as days leading to an event, that occurs in conjunction with a contest; (c) investigations of non-student drinking; and (d) objective assessments of opponent rating. Therefore, the present study: (1) examines the extent to which breath alcohol concentrations (BrAC) among restaurant and bar district patrons differ for low- and high-profile games and (2) explores the relationship between an objective rating of a team's opponent and BrAC levels. Data were collected throughout the fall 2011 football season via six anonymous field studies in a bar district within a southeastern college community. During low-profile game weekends, respondents recorded significantly lower BrAC levels than those during high-profile game weekends. Additionally, there was a positive correlation between opponent rating and BrAC levels, such that mean BrAC readings were highest prior to the game featuring the highest rated opponent. Overall, participants exhibited significantly higher BrACs when a higher-rated opponent was playing that weekend. When resources (money, manpower) are limited, community-based prevention and enforcement efforts should occur during the weekends surrounding higher-profile games.

A critical evaluation of magnetic activated carbon's potential for the remediation of sediment impacted by polycyclic aromatic hydrocarbons.

PubMed

Han, Zhantao; Sani, Badruddeen; Akkanen, Jarkko; Abel, Sebastian; Nybom, Inna; Karapanagioti, Hrissi K; Werner, David

2015-04-09

Addition of activated carbon (AC) or biochar (BC) to sediment to reduce the chemical and biological availability of organic contaminants is a promising in-situ remediation technology. But concerns about leaving the adsorbed pollutants in place motivate research into sorbent recovery methods. This study explores the use of magnetic sorbents. A coal-based magnetic activated carbon (MAC) was identified as the strongest of four AC and BC derived magnetic sorbents for polycyclic aromatic hydrocarbons (PAHs) remediation. An 8.1% MAC amendment (w/w, equal to 5% AC content) was found to be as effective as 5% (w/w) pristine AC in reducing aqueous PAHs within three months by 98%. MAC recovery from sediment after three months was 77%, and incomplete MAC recovery had both, positive and negative effects. A slight rebound of aqueous PAH concentrations was observed following the MAC recovery, but aqueous PAH concentrations then dropped again after six months, likely due to the presence of the 23% unrecovered MAC. On the other hand, the 77% recovery of the 8.1% MAC dose was insufficient to reduce ecotoxic effects of fine grained AC or MAC amendment on the egestion rate, growth and reproduction of the AC sensitive species Lumbriculus variegatus. Copyright © 2014 Elsevier B.V. All rights reserved.

The effects of pore structure on the behavior of water in lignite coal and activated carbon.

PubMed

Nwaka, Daniel; Tahmasebi, Arash; Tian, Lu; Yu, Jianglong

2016-09-01

The effects of physical structure (pore structure) on behavior of water in lignite coal and activated carbon (AC) samples were investigated by using Differential Scanning Calorimetry (DSC) and low-temperature X-ray diffraction (XRD) techniques. AC samples with different pore structures were prepared at 800°C in steam and the results were compared with that of parent lignite coal. The DSC results confirmed the presence of two types of freezable water that freeze at -8°C (free water) and -42°C (freezable bound water). A shift in peak position of free water (FW) towards lower temperature was observed in AC samples compared to the lignite coal with decreasing water loading. The amount of free water (FW) increased with increasing gasification conversion. The amounts of free and freezable bound water (FBW) in AC samples were calculated and correlated to pore volume and average pore size. The amount of FW in AC samples is well correlated to the pore volume and average pore size of the samples, while an opposite trend was observed for FBW. The low-temperature XRD analysis confirmed the existence of non-freezable water (NFW) in coal and AC with the boundary between the freezable and non-freezable water (NFW) determined. Copyright © 2016 Elsevier Inc. All rights reserved.

Diagnostic value of mean platelet volume (MPV) to troponin T inpatients with acute coronary syndrome

NASA Astrophysics Data System (ADS)

Aryanto, D.; Isnanta, R.; Safri, Z.; Hasan, R.

2018-03-01

Acute Coronary Syndrome (ACS) is used to describe the spectrum of coronary artery disease (CAD). Troponin T is the determinant of the most sensitive marker of ACS, but there aren’t all hospitals have this because of expensiveness. Mean Platelet Volume (MPV) is one of the components of a complete blood routine examination and relatively cheap as a marker in ACS. Determining the sensitivity and specificity of MPV in detecting cases of the acute coronary syndrome, 325 subjects’ medical records were from the period of July 2013 to June 2014; 228 ACS patients met the inclusion criteria. 228 subjects showed a risk factor for age ≥45years of more 195 (85.5%). 122 subjects with hypertension (53.5%) and subjects who smoked 118 (51.8%) that suffered most ACS. Subjects with risk factors for diabetes mellitus, obesity, menopause and dyslipidemia in this study was lower than non-diabetic 161 (70.6%), obese189 (82.9%), nonmenopause 196 (86%) and normal lipid 210 (92.1%). But there was norelation between risk factor with MPV and troponin T statistically. The results of diagnostic tests MPV for the evaluation of patients with ACS, sensitivity 92%, specificity 71%, positive predictive value 95% and negative predictive value 58%.

Does Parents' Social Cohesion Influence Their Perception of Neighborhood Safety and Their Children's Active Commuting to and From School?

PubMed

Salahuddin, Meliha; Nehme, Eileen; Ranjit, Nalini; Kim, Young-Jae; Oluyomi, Abiodun O; Dowdy, Diane; Lee, Chanam; Ory, Marcia; Hoelscher, Deanna M

2016-12-01

The role of parents' perceptions of the neighborhood environment in determining children's active commuting to and from school (ACS) is understudied. This study examined the association between parents' perceptions of neighborhood social cohesion, perceived neighborhood safety, and their children's ACS. This cross-sectional analysis (n = 857 from 81 elementary schools in Texas) examined baseline data from the Texas Childhood Obesity Prevention Policy Evaluation project. Participants had a mean age of 9.6 (0.6) years, and 50% were girls. Mixed effects logistic regression models were used to assess gender-stratified associations between parent's perceived social cohesion and children's ACS and their perception of neighborhood safety. A positive significant association was observed between levels of perceived social cohesion and children's ACS for boys (P = 0.047); however, an inverse significant association was observed among girls (P = 0.033). Parents of boys living in neighborhoods with medium to high social cohesion were more likely to perceive their neighborhood as safe compared with parents living in neighborhoods with low social cohesion, though nonsignificant. Perceived neighborhood safety for walking and biking was associated with greater ACS among boys (P = 0.003). Our study findings indicate that both social and physical environments are important factors in determining ACS among boys.

in silico identification of cross affinity towards Cry1Ac pesticidal protein with receptor enzyme in Bos taurus and sequence, structure analysis of crystal proteins for stability.

PubMed

Ebenezer, King Solomon; Nachimuthu, Ramesh; Thiagarajan, Prabha; Velu, Rajesh Kannan

2013-01-01

Any novel protein introduced into the GM crops need to be evaluated for cross affinity on living organisms. Many researchers are currently focusing on the impact of Bacillus thuringiensis cotton on soil and microbial diversity by field experiments. In spite of this, in silico approach might be helpful to elucidate the impact of cry genes. The crystal a protein which was produced by Bt at the time of sporulation has been used as a biological pesticide to target the insectivorous pests like Cry1Ac for Helicoverpa armigera and Cry2Ab for Spodoptera sp. and Heliothis sp. Here, we present the comprehensive in silico analysis of Cry1Ac and Cry2Ab proteins with available in silico tools, databases and docking servers. Molecular docking of Cry1Ac with procarboxypeptidase from Helicoverpa armigera and Cry1Ac with Leucine aminopeptidase from Bos taurus has showed the 125(th) amino acid position to be the preference site of Cry1Ac protein. The structures were compared with each other and it showed 5% of similarity. The cross affinity of this toxin that have confirmed the earlier reports of ill effects of Bt cotton consumed by cattle.

The impact of modifying photosystem antenna size on canopy photosynthetic efficiency—Development of a new canopy photosynthesis model scaling from metabolism to canopy level processes

PubMed Central

Song, Qingfeng; Wang, Yu; Qu, Mingnan; Ort, Donald R.

2017-01-01

Abstract Canopy photosynthesis (Ac) describes photosynthesis of an entire crop field and the daily and seasonal integrals of Ac positively correlate with daily and seasonal biomass production. Much effort in crop breeding has focused on improving canopy architecture and hence light distribution inside the canopy. Here, we develop a new integrated canopy photosynthesis model including canopy architecture, a ray tracing algorithm, and C3 photosynthetic metabolism to explore the option of manipulating leaf chlorophyll concentration ([Chl]) for greater Ac and nitrogen use efficiency (NUE). Model simulation results show that (a) efficiency of photosystem II increased when [Chl] was decreased by decreasing antenna size and (b) the light received by leaves at the bottom layers increased when [Chl] throughout the canopy was decreased. Furthermore, the modelling revealed a modest ~3% increase in Ac and an ~14% in NUE was accompanied when [Chl] reduced by 60%. However, if the leaf nitrogen conserved by this decrease in leaf [Chl] were to be optimally allocated to other components of photosynthesis, both Ac and NUE can be increased by over 30%. Optimizing [Chl] coupled with strategic reinvestment of conserved nitrogen is shown to have the potential to support substantial increases in Ac, biomass production, and crop yields. PMID:28755407

Memory for Object Locations: Priority Effect and Sex Differences in Associative Spatial Learning

ERIC Educational Resources Information Center

Cinan, Sevtap; Atalay, Deniz; Sisman, Simge; Basbug, Gokce; Dervent-Ozbek, Sevinc; Teoman, Dalga D.; Karagoz, Ayca; Karadeniz, A. Yezdan; Beykurt, Sinem; Suleyman, Hediye; Memis, H. Ozge; Yurtsever, Ozgur D.

2007-01-01

This paper reports two experiments conducted to examine priority effects and sex differences in object location memory. A new task of paired position-learning was designed, based on the A-B A-C paradigm, which was used in paired word learning. There were three different paired position-learning conditions: (1) positions of several different…

75 FR 59108 - Positive Train Control Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-27

... established. No railroad had supplied data supporting further track exceptions from PTC system installation...-0132, Notice No. 4] RIN 2130-AC03 Positive Train Control Systems AGENCY: Federal Railroad... Control (PTC) systems for railroads as mandated by the Rail Safety Improvement Act of 2008. With...

Physical properties of i-R-Cd quasicrystals(R = Y, Gd-Tm)

NASA Astrophysics Data System (ADS)

Kong, Tai; Bud'Ko, Sergey L.; Jesche, Anton; Goldman, Alan I.; Kreyssig, Andreas; Dennis, Kevin W.; Ramazanoglu, Mehmet; Canfield, Paul C.; McArthur, John

2014-03-01

Detailed characterization of recently discovered i-R-Cd (R = Y, Gd-Tm) binary quasicrystals by means of room-temperature powder x-ray diffraction, dc and ac magnetization, resistivity and specific heat measurements will be presented. i-Y-Cd is weakly diamagnetic. The dc magnetization of i-R-Cd (R = Gd, Ho-Tm) shows typical spin-glass type splitting between field-cooled (FC) and zero-field-cooled (ZFC) data. i-Tb-Cd and i-Dy-Cd do not show a clear cusp in their ZFC dc magnetization. ac magnetization measured on i-Gd-Cd indicates a clear frequency-dependence and the third-order non-linear magnetization, χ3, is consistent with a spin-glass transition. The resistivity for i-R-Cd is of order 100 μΩ cm and weakly temperature-dependent. No feature that can be associated with long-range magnetic order was observed in any of the measurements. Characteristic freezing temperatures for i-R-Cd (R = Gd-Tm) deviate from ideal de Gennes scaling. This work is supported by the US DOE, Basic Energy Sciences under Contract No. DE-AC02-07CH11358.

Identification and analysis of o-acetylated sialoglycoproteins.

PubMed

Mandal, Chandan; Mandal, Chitra

2013-01-01

5-N-acetylneuraminic acid, commonly known as sialic acid (Sia), constitutes a family of N- and O-substituted 9-carbon monosaccharides. Frequent modification of O-acetylations at positions C-7, C-8, or C-9 of Sias generates a family of O-acetylated sialic acid (O-AcSia) and plays crucial roles in many cellular events like cell-cell adhesion, proliferation, migration, etc. Therefore, identification and analysis of O-acetylated sialoglycoproteins (O-AcSGPs) are important. In this chapter, we describe several approaches for successful identification of O-AcSGPs. We broadly divide them into two categories, i.e., invasive and noninvasive methods. Several O-AcSias-binding probes are used for this purpose. Detailed methodologies for step-by-step identification using these probes have been discussed. We have also included a few invasive analytical methods for identification and quantitation of O-AcSias. Several indirect methods are also elaborated for such purpose, in which O-acetyl group from sialic acids is initially removed followed by detection of Sias by several approaches. For molecular identification, we have described methods for affinity purification of O-AcSGPs using an O-AcSias-binding lectin as an affinity matrix followed by sequencing using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF-TOF) mass spectroscopy (MS). In spite of special attention, loss of O-acetyl groups due to its sensitivity towards alkaline pH and high temperature along with migration of labile O-acetyl groups from C7-C8-C9 during sample preparation is difficult to avoid. Therefore there is always a risk for underestimation of O-AcSias.

The incremental value of troponin biomarkers in risk stratification of acute coronary syndromes: is the relationship multiplicative?

PubMed

Amin, Amit P; Nathan, Sandeep; Vassallo, Patricia; Calvin, James E

2009-05-20

To emphasize the importance of troponin in the context of a new score for risk stratifying acute coronary syndromes (ACS) patients. Although troponins have powerful prognostic value, current ACS scores do not fully capitalize this prognostic ability. Here, we weigh troponin status in a multiplicative manner to develop the TRACS score from previously published Rush score risk factors (RRF). 2,866 ACS patients (46.7% troponin positive) from 9 centers comprising the TRACS registry, were randomly split into derivation (n=1,422) and validation (n=1,444) cohorts. In the derivation sample, RRF sum was multiplied by 3 if troponins were positive to yield the TRACS score, which was grouped into five categories of 0-2, 3-5, 6-8, 9-11, 12-15 (multiples of 3). Predictive performance of this score to predict hospital death was ascertained in the validation sample. The TRACS score had ROC AUC of 0.71 in the validation cohort. Logistic regression, Kaplan-Meier analysis, likelihood-ratio and Bayesian Information Criterion (BIC) test indicated that weighing troponin status with 3 in the TRACS score improved the prediction of mortality. Hosmer-Lemeshow test indicated sound model fit. We demonstrate that weighing troponin as a multiple of 3 yields robust prognostication of hospital mortality in ACS patients, when used in the context of the TRACS score.

The Incremental Value of Troponin Biomarkers in Risk Stratification of Acute Coronary Syndromes: Is the Relationship Multiplicative?

PubMed Central

Amin, Amit P; Nathan, Sandeep; Vassallo, Patricia; Calvin, James E

2009-01-01

Structured Abstract Objective: To emphasize the importance of troponin in the context of a new score for risk stratifying acute coronary syndromes (ACS) patients. Although troponins have powerful prognostic value, current ACS scores do not fully capitalize this prognostic ability. Here, we weigh troponin status in a multiplicative manner to develop the TRACS score from previously published Rush score risk factors (RRF). Methods: 2,866 ACS patients (46.7% troponin positive) from 9 centers comprising the TRACS registry, were randomly split into derivation (n=1,422) and validation (n=1,444) cohorts. In the derivation sample, RRF sum was multiplied by 3 if troponins were positive to yield the TRACS score, which was grouped into five categories of 0-2, 3-5, 6-8, 9-11, 12-15 (multiples of 3). Predictive performance of this score to predict hospital death was ascertained in the validation sample. Results: The TRACS score had ROC AUC of 0.71 in the validation cohort. Logistic regression, Kaplan-Meier analysis, likelihood-ratio and Bayesian Information Criterion (BIC) test indicated that weighing troponin status with 3 in the TRACS score improved the prediction of mortality. Hosmer-Lemeshow test indicated sound model fit. Conclusions: We demonstrate that weighing troponin as a multiple of 3 yields robust prognostication of hospital mortality in ACS patients, when used in the context of the TRACS score. PMID:19557150

Application of ant colony optimization in development of models for prediction of anti-HIV-1 activity of HEPT derivatives.

PubMed

Zare-Shahabadi, Vali; Abbasitabar, Fatemeh

2010-09-01

Quantitative structure-activity relationship models were derived for 107 analogs of 1-[(2-hydroxyethoxy) methyl]-6-(phenylthio)thymine, a potent inhibitor of the HIV-1 reverse transcriptase. The activities of these compounds were investigated by means of multiple linear regression (MLR) technique. An ant colony optimization algorithm, called Memorized_ACS, was applied for selecting relevant descriptors and detecting outliers. This algorithm uses an external memory based upon knowledge incorporation from previous iterations. At first, the memory is empty, and then it is filled by running several ACS algorithms. In this respect, after each ACS run, the elite ant is stored in the memory and the process is continued to fill the memory. Here, pheromone updating is performed by all elite ants collected in the memory; this results in improvements in both exploration and exploitation behaviors of the ACS algorithm. The memory is then made empty and is filled again by performing several ACS algorithms using updated pheromone trails. This process is repeated for several iterations. At the end, the memory contains several top solutions for the problem. Number of appearance of each descriptor in the external memory is a good criterion for its importance. Finally, prediction is performed by the elitist ant, and interpretation is carried out by considering the importance of each descriptor. The best MLR model has a training error of 0.47 log (1/EC(50)) units (R(2) = 0.90) and a prediction error of 0.76 log (1/EC(50)) units (R(2) = 0.88). Copyright 2010 Wiley Periodicals, Inc.

Development and Validation of a Reversed Phase HPLC Method for Determination of Anacardic Acids in Cashew (Anacardium occidentale) Nut Shell Liquid.

PubMed

Oiram Filho, Francisco; Alcântra, Daniel Barbosa; Rodrigues, Tigressa Helena Soares; Alexandre E Silva, Lorena Mara; de Oliveira Silva, Ebenezer; Zocolo, Guilherme Julião; de Brito, Edy Sousa

2018-04-01

Cashew nut shell liquid (CNSL) contains phenolic lipids with aliphatic chains that are of commercial interest. In this work, a chromatographic method was developed to monitor and quantify anacardic acids (AnAc) in CNSL. Samples containing AnAc were analyzed on a high-performance liquid chromatograph coupled to a diode array detector, equipped with a reversed phase C18 (150 × 4.6 mm × 5 μm) column using acetonitrile and water as the mobile phase both acidified with acetic acid to pH 3.0 in an isocratic mode (80:20:1). The chromatographic method showed adequate selectivity, as it could clearly separate the different AnAc. To validate this method, AnAc triene was used as an external standard at seven different concentrations varying from 50 to 1,000 μg mL-1. The Student's t-test and F-test were applied to ensure high confidence for the obtained data from the analytical calibration curve. The results were satisfactory with respect to intra-day (relative standard deviation (RSD) = 0.60%) and inter-day (RSD = 0.67%) precision, linearity (y = 2,670.8x - 26,949, r2 > 0.9998), system suitability for retention time (RSD = 1.02%), area under the curve (RSD = 0.24%), selectivity and limits of detection (19.8 μg mg-1) and quantification (60.2 μg mg-1). The developed chromatographic method was applied for the analysis of different CNSL samples, and it was deemed suitable for the quantification of AnAc.

The association between pretest probability of coronary artery disease and stress test utilization and outcomes in a chest pain observation unit.

PubMed

Napoli, Anthony M

2014-04-01

Cardiology consensus guidelines recommend use of the Diamond and Forrester (D&F) score to augment the decision to pursue stress testing. However, recent work has reported no association between pretest probability of coronary artery disease (CAD) as measured by D&F and physician discretion in stress test utilization for inpatients. The author hypothesized that D&F pretest probability would predict the likelihood of acute coronary syndrome (ACS) and a positive stress test and that there would be limited yield to diagnostic testing of patients categorized as low pretest probability by D&F score who are admitted to a chest pain observation unit (CPU). This was a prospective observational cohort study of consecutively admitted CPU patients in a large-volume academic urban emergency department (ED). Cardiologists rounded on all patients and stress test utilization was driven by their recommendations. Inclusion criteria were as follows: age>18 years, American Heart Association (AHA) low/intermediate risk, nondynamic electrocardiograms (ECGs), and normal initial troponin I. Exclusion criteria were as follows: age older than 75 years with a history of CAD. A D&F score for likelihood of CAD was calculated on each patient independent of patient care. Based on the D&F score, patients were assigned a priori to low-, intermediate-, and high-risk groups (<10, 10 to 90, and >90%, respectively). ACS was defined by ischemia on stress test, coronary artery occlusion of ≥70% in at least one vessel, or elevations in troponin I consistent with consensus guidelines. A true-positive stress test was defined by evidence of reversible ischemia and subsequent angiographic evidence of critical stenosis or a discharge diagnosis of ACS. An estimated 3,500 patients would be necessary to have 1% precision around a potential 0.3% event rate in low-pretest-probability patients. Categorical comparisons were made using Pearson chi-square testing. A total of 3,552 patients with index visits were enrolled over a 29-month period. The mean (±standard deviation [SD]) age was 51.3 (±9.3) years. Forty-nine percent of patients received stress testing. Pretest probability based on D&F score was associated with stress test utilization (p<0.01), risk of ACS (p<0.01), and true-positive stress tests (p=0.03). No patients with low pretest probability were subsequently diagnosed with ACS (95% CI=0 to 0.66%) or had a true-positive stress test (95% CI=0 to 1.6%). Physician discretionary decision-making regarding stress test use is associated with pretest probability of CAD. However, based on the D&F score, low-pretest-probability patients who meet CPU admission criteria are very unlikely to have a true-positive stress test or eventually receive a diagnosis of ACS, such that observation and stress test utilization may be obviated. © 2014 by the Society for Academic Emergency Medicine.

Dirac points and van Hove singularities of silicene under uniaxial strain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Xianqing, E-mail: xqlin@zjut.edu.cn; College of Science, Zhejiang University of Technology, Hangzhou 310023; Ni, Jun

2015-04-28

First-principles calculations have been performed to investigate the low energy electronic properties and van Hove singularities (VHSs) of silicene under uniaxial strain. The Dirac points (DPs) persist when silicene is stretched uniaxially, while they are shifted away from the corners (K points) of the first Brillouin zone (FBZ). The relative positions of DPs with respect to the K points for silicene strained along the armchair (AC) or zigzag (ZZ) direction show opposite tendency compared with strained graphene, which is due to the larger deformation of the unit cell of strained silicene than that of strained graphene. Moreover, for silicene undermore » AC or ZZ strain, the Fermi velocities around DPs along the positive and negative directions of the FBZ show rather significant difference. The nature of the VHS just above the Fermi energy undergoes a transition from the π* band to the σ* band for silicene under increasing AC or ZZ strain. These observations suggest uniaxial strain as an effective route to tune the electronic properties of silicene for potential applications in future electronic devices.« less

Using interactive voice response to improve disease management and compliance with acute coronary syndrome best practice guidelines: A randomized controlled trial.

PubMed

Sherrard, Heather; Duchesne, Lloyd; Wells, George; Kearns, Sharon Ann; Struthers, Christine

2015-01-01

There is evidence from large clinical trials that compliance with standardized best practice guidelines (BPGs) improves survival of acute coronary syndrome (ACS) patients. However, their application is often suboptimal. In this study, the researchers evaluated whether the use of an interactive voice response (IVR) follow-up system improved ACS BPG compliance. This was a single-centre randomized control trial (RCT) of 1,608 patients (IVR=803; usual care=805). The IVR group received five automated calls in 12 months. The primary composite outcome was increased medication compliance and decreased adverse events. A significant improvement of 60% in the IVR group for the primary composite outcome was found (RR 1.60, 95% CI: 1.29 to 2.00, p <0.001). There was significant improvement in medication compliance (p <0.001) and decrease in unplanned medical visits (p = 0.023). At one year, the majority of patients ( 85%) responded positively to using the system again. Follow-up by IVR produced positive outcomes in ACS patients.

Activity of adenylyl cyclase and protein kinase A contributes to morphine-induced spinal apoptosis.

PubMed

Lim, Grewo; Wang, Shuxing; Lim, Jeong-Ae; Mao, Jianren

2005-12-02

Our previous study has shown that chronic morphine exposure induces neuronal apoptosis within the spinal cord dorsal horn; however, the mechanisms of morphine-induced apoptosis remain unclear. Here we examined whether adenylyl cyclase (AC) and protein kinase A (PKA) would play a role in this process. Intrathecal morphine regimen (10 microg, twice daily x 7 days) that resulted in antinociceptive tolerance induced spinal apoptosis as revealed by in situ terminal deoxynucleotidyl transferase (TdT)-UTP-biotin nick end labeling (TUNEL). The TUNEL-positive cells were detected primarily in the superficial laminae of the spinal cord dorsal horn, which was associated with an increase in the expression of activated caspase-3 and mitogen-activated protein kinase (MAPK) within the same spinal region. Co-administration of morphine with a broad AC inhibitor (ddA), a PKA inhibitor (H89), or a MAPK inhibitor (PD98059) substantially reduced the number of TUNEL-positive cells, as compared with the morphine alone group. The results indicate that the spinal AC and PKA pathway through intracellular MAPK may be contributory to the cellular mechanisms of morphine-induced apoptosis.

Life review based on remembering specific positive events in active aging.

PubMed

Latorre, José M; Serrano, Juan P; Ricarte, Jorge; Bonete, Beatriz; Ros, Laura; Sitges, Esther

2015-02-01

The aim of this study is to evaluate the effectiveness of life review (LR) based on specific positive events in non-depressed older adults taking part in an active aging program. Fifty-five older adults were randomly assigned to an experimental group or an active control (AC) group. A six-session individual training of LR based on specific positive events was carried out with the experimental group. The AC group undertook a "media workshop" of six sessions focused on learning journalistic techniques. Pre-test and post-test measures included life satisfaction, depressive symptoms, experiencing the environment as rewarding, and autobiographical memory (AM) scales. LR intervention decreased depressive symptomatology, improved life satisfaction, and increased specific memories. The findings suggest that practice in AM for specific events is an effective component of LR that could be a useful tool in enhancing emotional well-being in active aging programs, thus reducing depressive symptoms. © The Author(s) 2014.

Distribution-Agnostic Stochastic Optimal Power Flow for Distribution Grids: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baker, Kyri; Dall'Anese, Emiliano; Summers, Tyler

2016-09-01

This paper outlines a data-driven, distributionally robust approach to solve chance-constrained AC optimal power flow problems in distribution networks. Uncertain forecasts for loads and power generated by photovoltaic (PV) systems are considered, with the goal of minimizing PV curtailment while meeting power flow and voltage regulation constraints. A data- driven approach is utilized to develop a distributionally robust conservative convex approximation of the chance-constraints; particularly, the mean and covariance matrix of the forecast errors are updated online, and leveraged to enforce voltage regulation with predetermined probability via Chebyshev-based bounds. By combining an accurate linear approximation of the AC power flowmore » equations with the distributionally robust chance constraint reformulation, the resulting optimization problem becomes convex and computationally tractable.« less

Realizing the potential of the Actinium-225 radionuclide generator in targeted alpha-particle therapy applications

PubMed Central

Miederer, Matthias; Scheinberg, David A.; McDevitt, Michael R.

2013-01-01

Alpha particle-emitting isotopes have been proposed as novel cytotoxic agents for augmenting targeted therapy. Properties of alpha particle radiation such as their limited range in tissue of a few cell diameters and their high linear energy transfer leading to dense radiation damage along each alpha track are promising in the treatment of cancer, especially when single cells or clusters of tumor cells are targeted. Actinium-225 (225Ac) is an alpha particle-emitting radionuclide that generates 4 net alpha particle isotopes in a short decay chain to stable 209Bi, and as such can be described as an alpha particle nanogenerator. This article reviews the literature pertaining to the research, development, and utilization of targeted 225Ac to potently and specifically affect cancer. PMID:18514364

Analysis of improved dc and ac performances of an InGaP/GaAs heterojunction bipolar transistor with a graded Al xGa 1- xAs layer at emitter/base heterojunction

NASA Astrophysics Data System (ADS)

Cheng, Shiou-Ying

2004-07-01

An InGaP/GaAs heterojunction bipolar transistor (HBT) with a continuous conduction-band structure is demonstrated and theoretically investigated. This device exhibited good performance including lower turn-on voltage, lower offset voltage and smaller collector current saturation voltage. The novel aspect of device structure design is the adoption of the compositionally linear-graded AlGaAs layer between the InGaP-emitter and GaAs-base layers. Therefore, the device studied shows better dc and ac performances than a conventional device. Consequently, this causes the substantial benefit for practical analog and digital applications especially for lower operation voltage, lower power consumption commercial and military products.

The relationship of eco-friendly attitudes with walking and biking to work.

PubMed

Bopp, Melissa; Kaczynski, Andrew T; Wittman, Pamela

2011-01-01

Active commuting (AC) to work is an effective strategy for integrating regular physical activity (PA) into daily life routines, but limited research exists on influences of AC among adults. Current trends and interests toward environmental consciousness and sustainable forms of travel could impact transportation-related PA. The purpose of this study was to examine the association between eco-friendly attitudes (EFA) and several variables related to AC. A cross-sectional study of respondents to an online survey. Employed adults, physically able to walk or bicycle. The survey included questions about EFA, AC patterns, motivators and barriers for AC, and demographics. Eco-friendly attitudes were measured using a 9-item scale (eg, "I subscribe to ecological publications"). Participants were divided into quartiles on the basis of their EFA summary score (higher score = more ecologically friendly), and t tests and analyses of variance were used to make comparisons across groups on several variables related to AC. The sample (n = 375) was primarily young to middle-aged adults (mean age 39.4 ± 12.9 years), female (60.7%), and Caucasian (90.3%), with at least a high school education (94.6% with high school diploma or greater). Participants reported actively commuting an average of 2.4 ± 4.5 times per week and driving on average 8.4 ± 3.8 times per week. The mean EFA score was 33.4 ± 12.1 out of 63. Age was negatively related and education was positively related to EFA. Compared with those in the lower 3 quartiles, individuals in the top quartile of EFA scores were more likely to actively commute and less likely to drive and reported more self-efficacy, fewer barriers, and more motivators for AC. This study provides insight into potential influences on AC and possible strategies for intervention. Future studies should continue to investigate ecological attitudes as a possible moderator of AC behavior. Public health-based interventions to promote AC may use ecology-themed messages for greater reach and impact.

The role of lysine(100) in the binding of acetylcoenzyme A to human arylamine N-acetyltransferase 1: implications for other acetyltransferases.

PubMed

Minchin, Rodney F; Butcher, Neville J

2015-04-01

The arylamine N-acetyltransferases (NATs) catalyze the acetylation of aromatic and heterocyclic amines as well as hydrazines. All proteins in this family of enzymes utilize acetyl coenzyme A (AcCoA) as an acetyl donor, which initially binds to the enzyme and transfers an acetyl group to an active site cysteine. Here, we have investigated the role of a highly conserved amino acid (Lys(100)) in the enzymatic activity of human NAT1. Mutation of Lys(100) to either a glutamine or a leucine significantly increased the Ka for AcCoA without changing the Kb for the acetyl acceptor p-aminobenzoic acid. In addition, substrate inhibition was more marked with the mutant enzymes. Steady state kinetic analyzes suggested that mutation of Lys(100) to either leucine or glutamine resulted in a less stable enzyme-cofactor complex, which was not seen with a positively charged arginine at this position. When p-nitrophenylacetate was used as acetyl donor, no differences were seen between the wild-type and mutant enzymes because p-nitrophenylacetate is too small to interact with Lys(100) when bound to the active site. Using 3'-dephospho-AcCoA as the acetyl donor, kinetic data confirmed that Ly(100) interacts with the 3'-phosphoanion to stabilize the enzyme-cofactor complex. Mutation of Lys(100) decreases the affinity of AcCoA for the protein and increases the rate of CoA release. Crystal structures of several other unrelated acetyltransferases show a lysine or arginine residue within 3Å of the 3'-phosphoanion of AcCoA, suggesting that this mechanism for stabilizing the complex by the formation of a salt bridge may be widely applicable in nature. Copyright © 2015 Elsevier Inc. All rights reserved.

Serum neutrophil gelatinase-associated lipocalin levels are correlated with the complexity and the severity of atherosclerosis in acute coronary syndrome

PubMed Central

Soylu, Korhan; Aksan, Gökhan; Nar, Gökay; Özdemir, Metin; Gülel, Okan; İnci, Sinan; Aksakal, Aytekin; İdil Soylu, Ayşegül; Yılmaz, Özcan

2015-01-01

Objective: Neutrophil gelatinase-associated lipocalin (NGAL) is a novel inflammatory marker that is released from neutrophils. In this study, we evaluated the correlation between serum NGAL level and clinical and angiographic risk scores in patients diagnosed with non-ST elevation acute coronary syndrome (NSTE-ACS). Methods: Forty-seven random NSTE-ACS patients and 45 patients with normal coronary arteries (NCA) who underwent coronary angiography were enrolled in the study. GRACE risk score and SYNTAX and Gensini risk scores were used, respectively, for the purpose of clinical risk assessment and angiographic risk scoring. Serum NGAL level was measured via ELISA in peripheral blood samples obtained from the patients at the time of admission. Results: Serum NGAL level was significantly higher in the NSTE-ACS group compared to the control group (112.3±49.6 ng/mL vs. 58.1±24.3 ng/mL, p<0.001). There was a significant positive correlation between serum NGAL levels and the GRACE (r=0.533 and p<0.001), SYNTAX (r=0.395 and p=0.006), and Gensini risk scores (r=0.575 and p<0.001). The intermediate-high SYNTAX (>22) group had statistically significantly higher serum NGAL levels compared to the low SYNTAX (≤22) group (143±29.5 ng/mL vs. 98.7±43.2 ng/mL, p=0.001). Conclusion: NGAL level was positively correlated with lesion complexity and severity of coronary artery disease in patients with NSTE-ACS. Serum NGAL levels on admission are associated with increased burden of atherosclerosis in patients with NSTE-ACS. PMID:25430410

New structures and composition of cell wall teichoic acids from Nocardiopsis synnemataformans, Nocardiopsis halotolerans, Nocardiopsis composta and Nocardiopsis metallicus: a chemotaxonomic value.

PubMed

Tul'skaya, Elena M; Shashkov, Alexander S; Streshinskaya, Galina M; Potekhina, Natalia V; Evtushenko, Ludmila I

2014-12-01

The structures of the cell wall teichoic acids (TA) from some species of the genus Nocardiopsis were established by chemical and NMR spectroscopic methods. The cell walls of Nocardiopsis synnemataformans VKM Ac-2518(T) and Nocardiopsis halotolerans VKM Ac-2519(T) both contain two TA with unique structures-poly(polyol phosphate-glycosylpolyol phosphate)-belonging to the type IV TA. In both organisms, the minor TA have identical structures: poly(glycerol phosphate-N-acetyl-β-galactosaminylglycerol phosphate) with the phosphodiester bond between C-3 of glycerol and C-4 of the amino sugar. This structure is found for the first time. The major TA of N. halotolerans has a hitherto unknown structure: poly(glycerol phosphate-N-acetyl-β-galactosaminylglycerol phosphate), the N-acetyl-β-galactosamine being acetalated with pyruvic acid at positions 4 and 6. The major TA of N. synnemataformans is a poly(glycerol phosphate-N-acetyl-β-galactosaminylglycerol phosphate) with the phosphodiester bond between C-3 of glycerol and C-3 of the amino sugar. The cell walls of Nocardiopsis composta VKM Ac-2520 and N. composta VKM Ac-2521(T) contain only one TA, namely 1,3-poly(glycerol phosphate) partially substituted with N-acetyl-α-glucosamine. The cell wall of Nocardiopsis metallicus VKM Ac-2522(T) contains two TA. The major TA is 1,5-poly(ribitol phosphate), each ribitol unit carrying a pyruvate ketal group at positions 2 and 4. The structure of the minor TA is the same as that of N. composta. The results presented correlate well with the phylogenetic grouping of strains and confirm the species and strain specific features of cell wall TA in members of the genus Nocardiopsis.

Reduced Collagen Deposition in Infarcted Myocardium Facilitates Induced Pluripotent Stem Cell Engraftment and Angiomyogenesis for Improvement of Left Ventricular Function

PubMed Central

Dai, Bo; Huang, Wei; Xu, Meifeng; Millard, Ronald W.; Gao, Mei Hua; Hammond, H. Kirk; Menick, Donald R.; Ashraf, Muhammad; Wang, Yigang

2012-01-01

Objectives The purpose of this study was to assess the effect of scar tissue composition on engraftment of progenitor cells into infarcted myocardium. Background Scar tissue formation after myocardial infarction creates a barrier that severely compromises tissue regeneration, limiting potential functional recovery. Methods In vitro: A tricell patch (Tri-P) was created from peritoneum seeded and cultured with induced pluripotent stem cell–derived cardiomyocytes, endothelial cells, and mouse embryonic fibroblasts. The expression of fibrosis-related molecules from mouse embryonic fibroblasts and infarcted heart was measured by Western blot and quantitative reverse transcriptase polymerase chain reaction. In vivo: A Tri-P was affixed over the entire infarcted area 7 days after myocardial infarction in mice overexpressing adenylyl cyclase 6 (AC6). Engraftment efficiency of progenitor cells in hearts of AC6 mice was compared with that of control wild-type (WT) mice using a combination of in vivo bioluminescence imaging, post-mortem ex vivo tissue analysis, and the number of green fluorescent protein–positive cells. Echocardiography of left ventricular (LV) function was performed weekly. Hearts were harvested for analysis 4 weeks after Tri-P application. Mouse embryonic fibroblasts were stimulated with forskolin before an anoxia/reoxygenation protocol. Fibrosis-related molecules were analyzed. Results In AC6 mice, infarcted hearts treated with Tri-P showed significantly higher bioluminescence imaging intensity and numbers of green fluorescent protein–positive cells than in WT mice. LV function improved progressively in AC6 mice from weeks 2 to 4 and was associated with reduced LV fibrosis. Conclusions Application of a Tri-P in AC6 mice resulted in significantly higher induced pluripotent stem cell engraftment accompanied by angiomyogenesis in the infarcted area and improvement in LV function. PMID:22051336

Purification of HBsAg produced by the human hepatoma cell line PLC/PRE/5 by affinity chromatography using monoclonal antibodies and application for ELISA diagnostic.

PubMed

Merten, O W; Reiter, S; Scheirer, W; Katinger, H

1983-01-01

The human cell line PLC/PRF/5 (5) was used for the production of hepatitis B surface antigen subtype ad (HBsAg ad) and purified by affinity chromatography (AC) with monoclonal antibodies (mAb). mAb to HBsAg from mouse ascites have been purified by Protein A - AC prior coupling to AH-Sepharose 4B (Pharmacia). The combined procedure of ammonium-sulphate-precipitation of HBsAg from culture supernatants and immunosorbent-AC leads to approx. 700-fold purification. ELISA results using the mAb and the HBsAg for diagnostics of human serum, positive for anti-HBsAg-antibodies correlate with the RIA (AUSAB, Abbott).

Cell-Free circulating DNA: a new biomarker for the acute coronary syndrome.

PubMed

Cui, Ming; Fan, Mengkang; Jing, Rongrong; Wang, Huimin; Qin, Jingfeng; Sheng, Hongzhuan; Wang, Yueguo; Wu, Xinhua; Zhang, Lurong; Zhu, Jianhua; Ju, Shaoqing

2013-01-01

In recent studies, concentrations of cell-free circulating DNA (cf-DNA) have been correlated with clinical characteristics and prognosis in several diseases. The relationship between cf-DNA concentrations and the acute coronary syndrome (ACS) remains unknown. Moreover, no data are available for the detection cf-DNA in ACS by a branched DNA (bDNA)-based Alu assay. The aim of the present study was to investigate cf-DNA concentrations in ACS and their relationship with clinical features. Plasma cf-DNA concentrations of 137 ACS patients at diagnosis, of 60 healthy individuals and of 13 patients with stable angina (SA) were determined using a bDNA-based Alu assay. ACS patients (median 2,285.0, interquartile range 916.4-4,857.3 ng/ml), especially in ST-segment elevation myocardial infarction patients (median 5,745.4, interquartile range 4,013.5-8,643.9 ng/ml), showed a significant increase in plasma cf-DNA concentrations compared with controls (healthy controls: median 118.3, interquartile range 81.1-221.1 ng/ml; SA patients: median 202.3, interquartile range 112.7-256.1 ng/ml) using a bDNA-based Alu assay. Moreover, we found positive correlations between cf-DNA and Gensini scoring and GRACE (Global Registry of Acute Coronary Events) scoring in ACS. cf-DNA may be a valuable marker for diagnosing and predicting the severity of coronary artery lesions and risk stratification in ACS. Copyright © 2013 S. Karger AG, Basel.

Influence of mobile air-conditioning on vehicle emissions and fuel consumption: a model approach for modern gasoline cars used in Europe.

PubMed

Weilenmann, Martin F; Vasic, Ana-Marija; Stettler, Peter; Novak, Philippe

2005-12-15

The influence of air-conditioning activity on the emissions and fuel consumption of passenger cars is an important issue, since fleet penetration and use of these systems have reached a high level. Apart from the MOBILE6 study in the United States, little data is available on the impact of air-conditioning devices (A/Cs). Since weather conditions and A/C technologies both differ from those in the U. S., a test series was designed for the European setting. A fleet of six modern gasoline passenger cars was tested in different weather conditions. Separate test series were carried out for the initial cooldown and for the stationary situation of keeping the interior of the vehicle cool. As assumed, CO2 emissions and fuel consumption rise with the thermal load. This also causes a notable rise in CO and hydrocarbons (HCs). Moreover, A/Cs do not stop automatically at low ambient temperatures; if necessary, they produce dry air to demist the windscreen. A model is proposed that shows a constant load for lower temperatures and a linear trend for higher temperatures. The initial cooldown tests highlight significant differences among cars but show that A/C operation for the initial cooling of an overheated passenger compartment does not result in any extra emissions for the fleet as a whole.

Steric and electronic ligand perturbations in catalysis: asymmetric allylic substitution reactions using C2-symmetrical phosphorus-chiral (bi)ferrocenyl donors.

PubMed

Nettekoven, U; Widhalm, M; Kalchhauser, H; Kamer, P C; van Leeuwen, P W; Lutz, M; Spek, A L

2001-02-09

Three series of P-chiral diphosphines based on ferrocene (1a-f, 2a-c) and biferrocenyl skeletons (3a-c), including novel ligands 1f and 3c, were employed in palladium-catalyzed allylic substitution reactions. Steric effects imposed by the phosphine residues were studied using C2-symmetrical donors 1 (1 = 1,1'-bis(arylphenylphosphino)ferrocene with aryl groups a = 1-naphthyl, b = 2-naphthyl, c = 2-anisyl, d = 2-biphenylyl, e = 9-phenanthryl, and f = ferrocenyl), whereas para-methoxy- and/or para-trifluoromethyl substitution of the phenyl moieties in 1a enabled investigation of ligand electronic effects applying ferrocenyl diphosphines 2a-c. Ligands 3 (3 = 2,2'-bis- (arylphenylphosphino)-1,1'-biferrocenyls with aryl substituents a,c = 1-naphthyl (diastereomers) and b = 2-biphenylyl) allowed for comparison of backbone structure effects (bite angle variation) in catalysis. Linear and cyclic allylic acetates served as substrates in typical test reactions; upon attack of soft carbon and nitrogen nucleophiles on (E)-1,3-diphenylprop-2-ene-1-yl acetate the respective malonate, amine, or imide products were obtained in enantioselectivities of up to 99% ee. A crystal structure analysis of a palladium 1,3-diphenyl-eta 3-allyl complex incorporating ligand (S,S)-1a revealed a marked distortion of the allyl fragment, herewith defining the regioselectivity of nucleophile addition.

Driving Human Motor Cortical Oscillations Leads to Behaviorally Relevant Changes in Local GABAA Inhibition: A tACS-TMS Study.

PubMed

Nowak, Magdalena; Hinson, Emily; van Ede, Freek; Pogosyan, Alek; Guerra, Andrea; Quinn, Andrew; Brown, Peter; Stagg, Charlotte J

2017-04-26

Beta and gamma oscillations are the dominant oscillatory activity in the human motor cortex (M1). However, their physiological basis and precise functional significance remain poorly understood. Here, we used transcranial magnetic stimulation (TMS) to examine the physiological basis and behavioral relevance of driving beta and gamma oscillatory activity in the human M1 using transcranial alternating current stimulation (tACS). tACS was applied using a sham-controlled crossover design at individualized intensity for 20 min and TMS was performed at rest (before, during, and after tACS) and during movement preparation (before and after tACS). We demonstrated that driving gamma frequency oscillations using tACS led to a significant, duration-dependent decrease in local resting-state GABA A inhibition, as quantified by short interval intracortical inhibition. The magnitude of this effect was positively correlated with the magnitude of GABA A decrease during movement preparation, when gamma activity in motor circuitry is known to increase. In addition, gamma tACS-induced change in GABA A inhibition was closely related to performance in a motor learning task such that subjects who demonstrated a greater increase in GABA A inhibition also showed faster short-term learning. The findings presented here contribute to our understanding of the neurophysiological basis of motor rhythms and suggest that tACS may have similar physiological effects to endogenously driven local oscillatory activity. Moreover, the ability to modulate local interneuronal circuits by tACS in a behaviorally relevant manner provides a basis for tACS as a putative therapeutic intervention. SIGNIFICANCE STATEMENT Gamma oscillations have a vital role in motor control. Using a combined tACS-TMS approach, we demonstrate that driving gamma frequency oscillations modulates GABA A inhibition in the human motor cortex. Moreover, there is a clear relationship between the change in magnitude of GABA A inhibition induced by tACS and the magnitude of GABA A inhibition observed during task-related synchronization of oscillations in inhibitory interneuronal circuits, supporting the hypothesis that tACS engages endogenous oscillatory circuits. We also show that an individual's physiological response to tACS is closely related to their ability to learn a motor task. These findings contribute to our understanding of the neurophysiological basis of motor rhythms and their behavioral relevance and offer the possibility of developing tACS as a therapeutic tool. Copyright © 2017 Nowak et al.

Resonant soft X-ray scattering study of twist bend nematic, cholesteric and blue phases.

NASA Astrophysics Data System (ADS)

Slamonczyk, Miroslaw; Grecka, Ewa; Vaupotic, Natasa; Pociecha, Damian; Gleesom, Jim; Jakli, Antal; Sprunt, Sam; Wang, Cheng; Hexemer, Alexander; Zhu, Chenhui

We have demonstrated that, when operated at carbon K-edge, the linearly polarized soft X-rays can enable bond orientation sensitivity, which can be utilized to probe the otherwise forbidden peak from the helices of twist bend nematic and helical nanofilament phase. Here we show that the same principle can be used to probe blue phase and chiral nematic phase. Furthermore, we discuss the relationship between the incoming linearly polarized X-rays, and the anisotropy in the scattering pattern. Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02- 05CH11231.

Validation of Air Traffic Controller Workload Models

DTIC Science & Technology

1979-09-01

15 2.2 ATF Description ................................. 20 2.3 Summary of Changes to RECEP/ATF ............... 22 2.3.1 Definition of Routine...as an exhavistive descrip- tion. Emphasis is placed more on methodology while highlighting areas where changes in the process have oeen made as a... Change 3.7 2.2 Beacon (Discrete) Code 3.3 2.3 Mode C Altitude Report 2.9 2.0 A/C Position Report 3.0 2.6 A/C Altitude Report 2.0 2.6 Heading and Speed

Benzene exposure is associated with cardiovascular disease risk.

PubMed

Abplanalp, Wesley; DeJarnett, Natasha; Riggs, Daniel W; Conklin, Daniel J; McCracken, James P; Srivastava, Sanjay; Xie, Zhengzhi; Rai, Shesh; Bhatnagar, Aruni; O'Toole, Timothy E

2017-01-01

Benzene is a ubiquitous, volatile pollutant present at high concentrations in toxins (e.g. tobacco smoke) known to increase cardiovascular disease (CVD) risk. Despite its prevalence, the cardiovascular effects of benzene have rarely been studied. Hence, we examined whether exposure to benzene is associated with increased CVD risk. The effects of benzene exposure in mice were assessed by direct inhalation, while the effects of benzene exposure in humans was assessed in 210 individuals with mild to high CVD risk by measuring urinary levels of the benzene metabolite trans,trans-muconic acid (t,t-MA). Generalized linear models were used to assess the association between benzene exposure and CVD risk. Mice inhaling volatile benzene had significantly reduced levels of circulating angiogenic cells (Flk-1+/Sca-1+) as well as an increased levels of plasma low-density lipoprotein (LDL) compared with control mice breathing filtered air. In the human cohort, urinary levels of t,t-MA were inversely associated several populations of circulating angiogenic cells (CD31+/34+/45+, CD31+/34+/45+/AC133-, CD34+/45+/AC133+). Although t,t-MA was not associated with plasma markers of inflammation or thrombosis, t,t-MA levels were higher in smokers and in individuals with dyslipidemia. In smokers, t,t-MA levels were positively associated with urinary metabolites of nicotine (cotinine) and acrolein (3-hydroxymercapturic acid). Levels of t,t-MA were also associated with CVD risk as assessed using the Framingham Risk Score and this association was independent of smoking. Thus, benzene exposure is associated with increased CVD risk and deficits in circulating angiogenic cells in both smokers and non-smokers.

Comparing on-road real-time simultaneous in-cabin and outdoor particulate and gaseous concentrations for a range of ventilation scenarios

NASA Astrophysics Data System (ADS)

Leavey, Anna; Reed, Nathan; Patel, Sameer; Bradley, Kevin; Kulkarni, Pramod; Biswas, Pratim

2017-10-01

Advanced automobile technology, developed infrastructure, and changing economic markets have resulted in increasing commute times. Traffic is a major source of harmful pollutants and consequently daily peak exposures tend to occur near roadways or while travelling on them. The objective of this study was to measure simultaneous real-time particulate matter (particle numbers, lung-deposited surface area, PM2.5, particle number size distributions) and CO concentrations outside and in-cabin of an on-road car during regular commutes to and from work. Data was collected for different ventilation parameters (windows open or closed, fan on, AC on), whilst travelling along different road-types with varying traffic densities. Multiple predictor variables were examined using linear mixed-effects models. Ambient pollutants (NOx, PM2.5, CO) and meteorological variables (wind speed, temperature, relative humidity, dew point) explained 5-44% of outdoor pollutant variability, while the time spent travelling behind a bus was statistically significant for PM2.5, lung-deposited SA, and CO (adj-R2 values = 0.12, 0.10, 0.13). The geometric mean diameter (GMD) for outdoor aerosol was 34 nm. Larger cabin GMDs were observed when windows were closed compared to open (b = 4.3, p-value = <0.01). When windows were open, cabin total aerosol concentrations tracked those outdoors. With windows closed, the pollutants took longer to enter the vehicle cabin, but also longer to exit it. Concentrations of pollutants in cabin were influenced by outdoor concentrations, ambient temperature, and the window/ventilation parameters. As expected, particle number concentrations were impacted the most by changes to window position/ventilation, and PM2.5 the least. Car drivers can expect their highest exposures when driving with windows open or the fan on, and their lowest exposures during windows closed or the AC on. Final linear mixed-effects models could explain between 88 and 97% of cabin pollutant concentration variability. An individual may control their commuting exposure by applying dynamic behavior modification to adapt to changing pollutant scenarios.

Comparing on-road real-time simultaneous in-cabin and outdoor particulate and gaseous concentrations for a range of ventilation scenarios

PubMed Central

Leavey, Anna; Reed, Nathan; Patel, Sameer; Bradley, Kevin; Kulkarni, Pramod; Biswas, Pratim

2017-01-01

Advanced automobile technology, developed infrastructure, and changing economic markets have resulted in increasing commute times. Traffic is a major source of harmful pollutants and consequently daily peak exposures tend to occur near roadways or while traveling on them. The objective of this study was to measure simultaneous real-time particulate matter (particle numbers, lung-deposited surface area, PM2.5, particle number size distributions) and CO concentrations outside and in-cabin of an on-road car during regular commutes to and from work. Data was collected for different ventilation parameters (windows open or closed, fan on, AC on), whilst traveling along different road-types with varying traffic densities. Multiple predictor variables were examined using linear mixed-effects models. Ambient pollutants (NOx, PM2.5, CO) and meteorological variables (wind speed, temperature, relative humidity, dew point) explained 5–44% of outdoor pollutant variability, while the time spent travelling behind a bus was statistically significant for PM2.5, lung-deposited SA, and CO (adj-R2 values = 0.12, 0.10, 0.13). The geometric mean diameter (GMD) for outdoor aerosol was 34 nm. Larger cabin GMDs were observed when windows were closed compared to open (b = 4.3, p-value = <0.01). When windows were open, cabin total aerosol concentrations tracked those outdoors. With windows closed, the pollutants took longer to enter the vehicle cabin, but also longer to exit it. Concentrations of pollutants in cabin were influenced by outdoor concentrations, ambient temperature, and the window/ventilation parameters. As expected, particle number concentrations were impacted the most by changes to window position / ventilation, and PM2.5 the least. Car drivers can expect their highest exposures when driving with windows open or the fan on, and their lowest exposures during windows closed or the AC on. Final linear mixed-effects models could explain between 88–97% of cabin pollutant concentration variability. An individual may control their commuting exposure by applying dynamic behavior modification to adapt to changing pollutant scenarios. PMID:29284988