Evaluation of diatomea algae Thalassiosira weissflogii sensitivity to chloride mercury and methylmercury by chlorophyll fluorescence analysis

NASA Astrophysics Data System (ADS)

Graevskaya, E. E.; Antal, T. K.; Matorin, D. N.; Voronova, E. N.; Pogosyan, S. I.; Rubin, A. B.

2003-05-01

Measurement of chlorophyll fluorescence has been shown to be a rapid, non-invasive, and reliable method to assess photosynthetic performance in a changing environment. In our study, the pulseamplitude-modulation (PAM) - fluorometric method was used to evaluate the sensitivity to chloride mercury and methylmercury chloride of diatomea microalgae Thalassiosira weissflogii. We found that 10^{-6} and 10^{-7} M MeHg led to a slow decrease in the PS II activity following for prolonged lag phase, whereas the algae was not sensitive to the same concentrations of HgCl2. However observed PS II inactivation by methylmercury was not complete and about 10 percents ofthe cells kept the high level of PS II activity as it was shown by microfluorometric analysis. These cells could determine adaptation of algae to methylmercury effect. Both toxicants decreased the rate of PS II reparation, as well as increased a heat pathway of excitation dissipation in PS II antennae complex.

Engine of life and big bang of evolution: a personal perspective.

PubMed

Barber, James

2004-01-01

Photosystem II (PS II) is the engine for essentially all life on our planet and its beginning 2.5 billion years ago was the 'big bang of evolution.' It produces reducing equivalents for making organic compounds on an enormous scale and at the same time provides us with an oxygenic atmosphere and protection against UV radiation (in the form of the ozone layer). In 1967, when I began my career in photosynthesis research, little was known about PS II. The Z-scheme had been formulated [Hill and Bendall (1960) Nature 186: 136-137] and Boardman and Anderson [(1964) Nature 203: 166-167] had isolated PS II as a discrete biochemical entity. PS II was known not only to be the source of oxygen but of variable chlorophyll fluorescence [Duysens and Sweers (1963) In: Studies on Microalgae and Photosynthetic Bacteria, pp. 353-372. University of Tokyo Press, Tokyo] and delayed chlorophyll fluorescence [Arnold and Davidson (1954) J Gen Physiol 37: 677-684]. P680 had just been discovered [Döring et al. (1967) Z Naturforsch 22b: 639-644]. No wonder the 'black box of PS II' was described at that time by Bessel Kok and George Cheniae [Current Topics in Bioenergetics 1: 1-47 (1966)] as the 'inner sanctum of photosynthesis.' What a change in our level of understanding of PS II since then! The contributions of many talented scientists have unraveled the mechanisms and structural basis of PS II function and we are now very close to revealing the molecular details of the remarkable and thermodynamically demanding reaction which it catalyzes, namely the splitting of water into its elemental constituents. It has been a privilege to be involved in this journey.

Formation of tyrosine radicals in photosystem II under far-red illumination.

PubMed

Ahmadova, Nigar; Mamedov, Fikret

2018-04-01

Photosystem II (PS II) contains two redox-active tyrosine residues on the donor side at symmetrical positions to the primary donor, P 680 . Tyr Z , part of the water-oxidizing complex, is a preferential fast electron donor while Tyr D is a slow auxiliary donor to P 680 + . We used PS II membranes from spinach which were depleted of the water oxidation complex (Mn-depleted PS II) to study electron donation from both tyrosines by time-resolved EPR spectroscopy under visible and far-red continuous light and laser flash illumination. Our results show that under both illumination regimes, oxidation of Tyr D occurs via equilibrium with Tyr Z • at pH 4.7 and 6.3. At pH 8.5 direct Tyr D oxidation by P 680 + occurs in the majority of the PS II centers. Under continuous far-red light illumination these reactions were less effective but still possible. Different photochemical steps were considered to explain the far-red light-induced electron donation from tyrosines and localization of the primary electron hole (P 680 + ) on the Chl D1 in Mn-depleted PS II after the far-red light-induced charge separation at room temperature is suggested.

[PS II photochemical efficiency in flag leaf of wheat varieties and its adaptation to strong sun- light intensity on farmland of Xiangride in Qinghai Province, Northwest China].

PubMed

Shi, Sheng-Bo; Chen, Wen-Jie; Shi, Rui; Li, Miao; Zhang, Huai-Gang; Sun, Ya-Nan

2014-09-01

Taking four wheat varieties developed by Northwest Institute of Plateau Biology, Chinese Academy of Sciences, as test materials, with the measurement of content of photosynthetic pigments, leaf area, fresh and dry mass of flag leaf, the PS II photochemistry efficiency of abaxial and adaxial surface of flag leaf and its adaptation to strong solar radiation during the period of heading stage in Xiangride region were investigated with the pulse-modulated in-vivo chlorophyll fluorescence technique. The results indicated that flag leaf angle mainly grew in horizontal state in Gaoyuan 314, Gaoyuan 363 and Gaoyuan 584, and mainly in vertical state in Gaoyuan 913 because of its smaller leaf area and larger width. Photosynthetic pigments were different among the 4 varieties, and positively correlated with intrinsic PS II photochemistry efficiencies (Fv/Fm). In clear days, especially at noon, the photosynthetic photoinhibition was more serious in abaxial surface of flag leaf due to directly facing the solar radiation, but it could recover after reduction of sunlight intensity in the afternoon, which meant that no inactive damage happened in PS II reaction centers. There were significant differences of PS II actual and maximum photochemical efficiencies at the actinic light intensity (ΦPS II and Fv'/Fm') between abaxial and adaxial surface, and their relative variation trends were on the contrary. The photochemical and non-photochemical quenching coefficients (qP and NPQ) had a similar tendency in both abaxial and adaxial surfaces. Although ΦPS II and qP were lower in adaxial surface of flag leaf, the Fv'/Fm' was significantly higher, which indicated that the potential PS II capture efficiency of excited energy was higher. The results demonstrated that process of photochemical and non-photochemical quenching could effectively dissipate excited energy caused by strong solar radiation, and there were higher adaptation capacities in wheat varieties natively cultivated in Qinghai-Tibetan Plateau area.

Freezing cytorrhysis and critical temperature thresholds for photosystem II in the peat moss Sphagnum capillifolium.

PubMed

Buchner, Othmar; Neuner, Gilbert

2010-07-01

Leaflets of Sphagnum capillifolium were exposed to temperatures from -5 degrees C to +60 degrees C under controlled conditions while mounted on a microscope stage. The resultant cytological response to these temperature treatments was successfully monitored using a light and fluorescence microscope. In addition to the observable cytological changes during freezing cytorrhysis and heat exposure on the leaflets, the concomitant critical temperature thresholds for inactivation of photosystem II (PS II) were studied using a micro fibre optic and a chlorophyll fluorometer mounted to the microscope stage. Chlorophyllous cells of S. capillifolium showed extended freezing cytorrhysis immediately after ice nucleation at -1.1 degrees C in the water in which the leaflets were submersed during the measurement. The occurrence of freezing cytorrhysis, which was visually manifested by cell shrinkage, was highly dynamic and was completed within 2 s. A total reduction of the mean projected diameter of the chloroplast containing area during freezing cytorrhysis from 8.9 to 3.8 microm indicates a cell volume reduction of approximately -82%. Simultaneous measurement of chlorophyll fluorescence of PS II was possible even through the frozen water in which the leaf samples were submersed. Freezing cytorrhysis was accompanied by a sudden rise of basic chlorophyll fluorescence. The critical freezing temperature threshold of PS II was identical to the ice nucleation temperature (-1.1 degrees C). This is significantly above the temperature threshold at which frost damage to S. capillifolium leaflets occurs (-16.1 degrees C; LT(50)) which is higher than observed in most higher plants from the European Alps during summer. High temperature thresholds of PS II were 44.5 degrees C which is significantly below the heat tolerance of chlorophyllous cells (49.9 degrees C; LT(50)). It is demonstrated that light and fluorescence microscopic techniques combined with simultaneous chlorophyll fluorescence measurements may act as a useful tool to study heat, low temperature, and ice-encasement effects on the cellular structure and primary photosynthetic processes of intact leaf tissues.

X-ray absorption spectroscopy and EPR studies of oriented spinach thylakoid preparations

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

Andrews, J.C.

In this study, oriented Photosystem II (PS II) particles from spinach chloroplasts are studied with electron paramagnetic resonance (EPR) and x-ray absorption spectroscopy (XAS) to determine more details of the structure of the oxygen evolving complex (OEC). The nature of halide binding to Mn is also studied with Cl K-edge and Mn EXAFS (extended x-ray absorption fine structure) of Mn-Cl model compounds, and with Mn EXAFS of oriented PS II in which Br has replaced Cl. Attention is focused on the following: photosynthesis and the oxygen evolving complex; determination of mosaic spread in oriented photosystem II particles from signal IImore » EPR measurement; oriented EXAFS--studies of PS II in the S{sub 2} state; structural changes in PS II as a result of treatment with ammonia: EPR and XAS studies; studies of halide binding to Mn: Cl K-edge and Mn EXAFS of Mn-Cl model compounds and Mn EXAFS of oriented Br-treated photosystem II.« less

[Perioperative mortality and morbidity in the year 2000 in 502 Japanese certified anesthesia-training hospitals: with a special reference to ASA-physical status--report of the Japan Society of Anesthesiologists Committee on Operating Room Safety].

PubMed

Irita, Kazuo; Kawashima, Yasuo; Tsuzaki, Koichi; Iwao, Yasuhide; Kobayashi, Tsutomu; Seo, Norimasa; Goto, Yasuyuki; Morita, Kiyoshi; Shiraishi, Yoshito; Nakao, Yasuo; Tanaka, Yoshifumi; Tosaki, Youko; Dohi, Shuji; Obara, Hidefumi

2002-01-01

Perioperative mortality and morbidity in Japan from Jan. 1 to Dec. 31, 2000 were studied retrospectively. Committee on Operating Room Safety in Japanese Society of Anesthesiologists (JSA) sent confidential questionnaires to 794 certified training hospitals of JSA and received answers from 67.6% of the hospitals. We analyzed their answers with a special reference to ASA physical status (ASA-PS). The total number of anesthesia available for this analysis was 897,733. The percentages of patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E are 38.0, 40.3, 8.5, 0.4, 4.3, 5.3, 2.5, and 0.7%, respectively. Mortality and morbidity from all kinds of causes including anesthetic management, intraoperative events, co-existing diseases, and surgical problems were as follows. The incidences of cardiac arrest (per 10,000 cases of anesthesia) were 1.11, 3.26, 12.25, 54.60, 0.77, 4.46, 21.08 and 217.75 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The incidences of critical events including cardiac arrest, severe hypotension, and severe hypoxemia were 6.89, 20.22, 62.18, 148.21, 6.71, 20.38, 106.72 and 592.21 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The mortality rates (death during anesthesia and within 7 postoperative days) after cardiac arrest were 0.26, 0.77, 3.69, 41.60, 0.00, 1.06, 9.42 and 163.31 per 10,000 cases of anesthesia in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The overall mortality rates were 0.32, 1.38, 9.75, 70.20, 0.26, 2.12, 29.15 and 353.02 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. Overall mortality and morbidity were higher in emergency anesthesia than in elective anesthesia. ASA-PS correlated well with overall mortality and morbidity, regardless of etiology. The incidences of cardiac arrest totally attributable to anesthesia were 0.23, 0.50, 1.32, 0.00, 0.00, 0.85, 2.69 and 4.95 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The incidences of all critical events totally attributable to anesthesia were 3.13, 5.56, 11.46, 5.20, 3.87, 5.94, 13.90 and 14.85 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The mortality rates after cardiac arrest totally attributable to anesthesia were 0.03, 0.03, 0.00, 0.00, 0.00, 0.21, 0.45 and 3.30 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The overall mortality rates totally attributable to anesthesia were 0.03, 0.06, 0.00, 0.00, 0.00, 0.21, 0.45 and 6.60 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The overall mortality rate totally attributable to anesthesia among patients with good physical status (ASA-PS of I, II, I E, II E) was 0.05. Anesthetic management was mainly responsible for critical events in patients with good physical status, while coexisting diseases were in those with poor physical status. Surgical problems including procedures and massive hemorrhage were the leading causes of mortality in patients with good physical status. We reconfirmed that ASA-PS is useful to predict perioperative mortality and morbidity. It also seems likely that we should make much more efforts to reduce anesthetic morbidity in patients with good physical status, and to improve preanesthetic assessment and preparation in those with poor physical status. Reducing mortality and morbidity from surgical problems is also required for improving perioperative mortality.

Study of cell-differentiation and assembly of photosynthetic proteins during greening of etiolated Zea mays leaves using confocal fluorescence microspectroscopy at liquid-nitrogen temperature.

PubMed

Shibata, Yutaka; Katoh, Wataru; Tahara, Yukari

2013-04-01

Fluorescence microspectroscopy observations were used to study the processes of cell differentiation and assemblies of photosynthesis proteins in Zea mays leaves under the greening process. The observations were done at 78K by setting the sample in a cryostat to avoid any undesired progress of the greening process during the measurements. The lateral and axial spatial resolutions of the system were 0.64μm and 4.4μm, respectively. The study revealed the spatial distributions of protochlorophyllide (PChld) in both the 632-nm-emitting and 655-nm-emitting forms within etiolated Zea mays leaves. The sizes of the fluorescence spots attributed to the former were larger than those of the latter, validating the assignment of the former and latter to the prothylakoid and prolamellar bodies, respectively. In vivo microspectroscopy observations of mature Zea mays leaves confirmed the different photosystem II (PS I)/photosystem I (PS II) ratio between the bundle sheath (BS) and mesophyll (MS) cells, which is specific for C4-plants. The BS cells in Zea mays leaves 1h after the initiation of the greening process tended to show fluorescence spectra at shorter wavelength side (at around 679nm) than the MS cells (at around 682nm). The 679-nm-emitting chlorophyll-a form observed mainly in the BS cells was attributed to putative precursor complexes to PS I. The BS cells under 3-h greening showed higher relative intensities of the PS I fluorescence band at around 735nm, suggesting the reduced PS II amount in the BS cells in this greening stage. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of angiotensin II on proliferation and differentiation of mouse induced pluripotent stem cells into mesodermal progenitor cells

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

Ishizuka, Toshiaki, E-mail: tishizu@ndmc.ac.jp; Goshima, Hazuki; Ozawa, Ayako

2012-03-30

Highlights: Black-Right-Pointing-Pointer Treatment with angiotensin II enhanced LIF-induced DNA synthesis of mouse iPS cells. Black-Right-Pointing-Pointer Angiotensin II may enhance the DNA synthesis via induction of superoxide. Black-Right-Pointing-Pointer Treatment with angiotensin II significantly increased JAK/STAT3 phosphorylation. Black-Right-Pointing-Pointer Angiotensin II enhanced differentiation into mesodermal progenitor cells. Black-Right-Pointing-Pointer Angiotensin II may enhance the differentiation via activation of p38 MAPK. -- Abstract: Previous studies suggest that angiotensin receptor stimulation may enhance not only proliferation but also differentiation of undifferentiated stem/progenitor cells. Therefore, in the present study, we determined the involvement of the angiotensin receptor in the proliferation and differentiation of mouse induced pluripotent stemmore » (iPS) cells. Stimulation with angiotensin II (Ang II) significantly increased DNA synthesis in mouse iPS cells cultured in a medium with leukemia inhibitory factor (LIF). Pretreatment of the cells with either candesartan (a selective Ang II type 1 receptor [AT{sub 1}R] antagonist) or Tempol (a cell-permeable superoxide scavenger) significantly inhibited Ang II-induced DNA synthesis. Treatment with Ang II significantly increased JAK/STAT3 phosphorylation. Pretreatment with candesartan significantly inhibited Ang II- induced JAK/STAT3 phosphorylation. In contrast, induction of mouse iPS cell differentiation into Flk-1-positive mesodermal progenitor cells was performed in type IV collagen (Col IV)- coated dishes in a differentiation medium without LIF. When Col IV-exposed iPS cells were treated with Ang II for 5 days, the expression of Flk-1 was significantly increased compared with that in the cells treated with the vehicle alone. Pretreatment of the cells with both candesartan and SB203580 (a p38 MAPK inhibitor) significantly inhibited the Ang II- induced increase in Flk-1 expression. Treatment with Ang II enhanced the phosphorylation of p38 MAPK in Col IV- exposed iPS cells. These results suggest that the stimulation of mouse iPS cells with AT{sub 1}R may enhance LIF-induced DNA synthesis, by augmenting the generation of superoxide and activating JAK/STAT3, and that AT{sub 1}R stimulation may enhance Col IV-induced differentiation into mesodermal progenitor cells via p38 MAPK activation.« less

Impact of nitrophenols on the photosynthetic electron transport chain and ATP content in Nostoc muscorum and Chlorella vulgaris.

PubMed

Umamaheswari, A; Venkateswarlu, K

2004-06-01

Concentration-dependent inhibition of the photosynthetic electron transport chain (photosystem I (PS I), photosystem II (PS II) and whole chain reaction) and ATP content was observed in Nostoc muscorum and Chlorella vulgaris grown with o-nitrophenol, m-nitrophenol, or 2,4-dinitrophenol. Although the extents of inhibition of the photosynthetic electron transport chain in both organisms were similar, PS II was more sensitive than PS I and whole chain reaction to the nitrophenols. Depletion of the ATP pool was noted in nitrophenol-grown cultures, probably as a consequence of nearly complete inhibition of the photosynthetic electron transport chain.

Efficient biodegradation of acephate by Pseudomonas pseudoalcaligenes PS-5 in the presence and absence of heavy metal ions [Cu(II) and Fe(III)], and humic acid.

PubMed

Singh, Simranjeet; Kumar, Vijay; Upadhyay, Niraj; Singh, Joginder; Singla, Sourav; Datta, Shivika

2017-08-01

The present study was intended to investigate the biodegradation of acephate in aqueous media in the presence and in the absence of metal ions [Fe(III) and Cu(II)], and humic acid (HA). Biodegradations were performed using Pseudomonas pseudoalcaligenes PS-5 (PS-5) isolated from the heavy metal polluted site. Biodegradations were monitored by UV-Visible, FTIR, and electron spray ionization-mass spectrometry (ESI-MS) analyses. ESI-MS analysis revealed that PS-5 degraded acephate to two metabolites showing intense ions at mass-to-charge ratios ( m / z ) 62 and 97. The observed kinetic was the pseudo-first order, and half-life periods ( t 1/2 ) were 2.79 d -1 (of PS-5 + acephate), 3.45 d -1 [of PS-5 + acephate + Fe(III)], 3.16 d -1 [of PS-5 + acephate + Cu(II)], and 5.54 d -1 (of PS-5 + acephate + HA). A significant decrease in degradation rate of acephate was noticed in the presence of HA, and the same was confirmed by UV-Visible and TGA analyses. Strong aggregation behavior of acephate with humic acid in aqueous media was the major cause behind the slow degradation rate of acephate . New results on acephate metabolism by strain PS-5 in the presence and in the absence of metal ions [Fe(III) and Cu(II)] and humic acid were obtained. Results confirmed that Pseudomonas pseudoalcaligenes strain PS-5 was capable of mineralization of the acephate without formation of toxic metabolite methamidophos. More significantly, the Pseudomonas pseudoalcaligenes strain PS-5 could be useful as potential biological agents in effective bioremediation campaign for multi-polluted environments.

Uphill energy transfer from long-wavelength absorbing chlorophylls to PS II in Ostreobium sp. is functional in carbon assimilation.

PubMed

Wilhelm, Christian; Jakob, Torsten

2006-03-01

From the algal genus Ostrobium two species are known which express a chlorophyll antenna absorbing between 710 and 725 nm to a different extent. In a comparative study with these two species it is shown that quanta absorbed by this long wavelength antenna can be transferred to PS II leading to significant PS II-related electron transfer. It is documented that under monochromatic far red light illumination growth continues with rather high efficiency. The data show that the uphill-energy transfer to PS II reduces the quantum yield under white light significantly. It is discussed that this strategy of energy conversion might play a role in special environments where far red light is the predominant energy source.

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

Vermaas, Willem

The proposed research seeks to address two interconnected, important questions that impact photosynthetic processes and that reflect key differences between the photosynthetic systems of cyanobacteria and plants or algae. The first question is what are the reasons and consequences of the high photosystem I / photosystem II (PS I/PS II) ratio in many cyanobacteria, vs. a ratio that is close to unity in many plants and algae. The corresponding hypothesis is that most of PS I functions in cyclic electron transport, and that reduction in PS I will result primarily in a shortage of ATP rather than reducing power. Thismore » hypothesis will be tested by reducing the amount of PS I by changing the promoter region of the psaAB operon in the cyanobacterium Synechocystis sp. PCC 6803 and generating a range of mutants with different PS I content and thereby different PS I/PS II ratios, with some of the mutants having a PS II/PS I ratio closer to that in plants. The resulting mutants will be probed in terms of their growth rates, electron transfer rates, and P700 redox kinetics. A second question relates to a Mehler-type reaction catalyzed by two flavoproteins, Flv1 and Flv3, that accept electrons from PS I and that potentially function as an electron safety valve leading to no useful purpose of the photosynthesis-generated electrons. The hypothesis to be tested is that Flv1 and Flv3 use the electrons for useful purposes such as cyclic electron flow around PS I. This hypothesis will be tested by analysis of a mutant strain lacking flv3, the gene for one of the flavoproteins. This research is important for a more detailed understanding of the consequences of photosystem stoichiometry and amounts in a living system. Such an understanding is critical for not only insights in the regulatory systems of the organism but also to guide the development of biological or bio-hybrid systems for solar energy conversion into fuels.« less

Ultrafast Primary Reactions in the Photosystems of Oxygen-Evolving Organisms

NASA Astrophysics Data System (ADS)

Holzwarth, A. R.

In oxygen-evolving photosynthetic organisms (plants, green algae, cyanobacteria), the primary steps of photosynthesis occur in two membrane-bound protein supercomplexes, Photosystem I (PS I) and Photosystem II (PS II), located in the thylakoid membrane (c.f. Fig. 7.1) along with two other important protein complexes, the cytochrome b6/f complex and the ATP-synthase [1]. Each of the photosystems consists of a reaction center (RC) where the photoinduced early electron transfer processes occur, of a so-called core antenna consisting of chlorophyll (Chl) protein complexes responsible for light absorption and ultrafast energy transfer to the RC pigments, and additional peripheral antenna complexes of various kinds that increase the absorption cross-section. The peripheral complexes are Chl a/b-protein complexes in higher plants and green algae (LHC I or LHC II for PS I or PS II, respectively) and so-called phycobilisomes in cyanobacteria and red algae [2-4]. The structures and light-harvesting functions of these antenna systems have been extensively reviewed [2, 5-9]. Recently, X-ray structures of both PS I and PS II antenna/RC complexes have been determined, some to atomic resolution. Although many details of the pigment content and organization of the RCs and antenna systems of PS I and PS II have been known before, the high resolution structures of the integral complexes allow us for the first time to try to understand structure/function relationships in detail. This article covers our present understanding of the ultrafast energy transfer and early electron transfer processes occurring in the photosystems of oxygen-evolving organisms. The main emphasis will be on the electron transfer processes. However, in both photosystems the kinetics of the energy transfer processes in the core antennae is intimately interwoven with the kinetics of the electron transfer steps. Since both types of processes occur on a similar time scale, their kinetics cannot be considered separately in any experiment and consequently they have to be discussed together.

VizieR Online Data Catalog: RR Lyrae stars from the PS1 3π survey (Sesar+, 2017)

NASA Astrophysics Data System (ADS)

Sesar, B.; Hernitschek, N.; Mitrovic, S.; Ivezic, Z.; Rix, H.-W.; Cohen, J. G.; Bernard, E. J.; Grebel, E. K.; Martin, N. F.; Schlafly, E. F.; Burgett, W. S.; Draper, P. W.; Flewelling, H.; Kaiser, N.; Kudritzki, R. P.; Magnier, E. A.; Metcalfe, N.; Tonry, J. L.; Waters, C.

2018-04-01

Building on the work by Hernitschek+ (2016, J/ApJ/817/73), in this paper, we use the final PS1 data release (PV3) to significantly increase the completeness and purity of the PS1 sample of RR Lyrae stars. Pan-STARRS1 (PS1; Kaiser+ 2010, see II/349) is a wide-field optical/near-IR survey telescope system located at the Haleakala Observatory on the island of Maui in Hawai'i. The largest survey undertaken by the telescope, the PS1 3π survey (Chambers K.C. 2011, BAAS, 43, 113.01), has observed the entire sky north of decl. -30° in five filter bands, reaching 5σ single-epoch depths of about 22.0, 22.0, 21.9, 21.0, and 19.8mag in gP1, rP1, iP1, zP1, and yP1 bands, respectively. The uncertainty in photometric calibration of the survey is <~0.01mag, and the astrometric precision of single-epoch detections is 10mas. (4 data files).

Spraying Brassinolide improves Sigma Broad tolerance in foxtail millet (Setaria italica L.) through modulation of antioxidant activity and photosynthetic capacity.

PubMed

Yuan, Xiang-Yang; Zhang, Li-Guang; Huang, Lei; Yang, Hui-Jie; Zhong, Yan-Ting; Ning, Na; Wen, Yin-Yuan; Dong, Shu-Qi; Song, Xi-E; Wang, Hong-Fu; Guo, Ping-Yi

2017-09-11

To explore the role of Brassinolide (BR) in improving the tolerance of Sigma Broad in foxtail millet (Setaria italica L.), effects of 0.1 mg/L of BR foliar application 24 h before 3.37 g/ha of Sigma Broad treatment at five-leaf stage of foxtail millet on growth parameters, antioxidant enzymes, malondialdehyde (MDA), chlorophyll, net photosynthetic rate (P N ), chlorophyll fluorescence and P 700 parameters were studied 7 and 15 d after herbicide treatment, respectively. Results showed that Sigma Broad significantly decreased plant height, activities of superoxide dismutase (SOD), chlorophyll content, P N , PS II effective quantum yield (Y (II)), PS II electron transport rate (ETR (II)), photochemical quantum yield of PSI(Y (I)) and PS I electron transport rate ETR (I), but significantly increased MDA. Compared to herbicide treatment, BR dramatically increased plant height, activities of SOD, Y (II), ETR (II), Y (I) and ETR (I). This study showed BR pretreatment could improve the tolerance of Sigma Broad in foxtail millet through improving the activity of antioxidant enzymes, keeping electron transport smooth, and enhancing actual photochemical efficiency of PS II and PSI.

Adsorption of transition metal ions from aqueous solutions onto a novel silica gel matrix inorganic-organic composite material.

PubMed

Yin, Ping; Xu, Qiang; Qu, Rongjun; Zhao, Guifang; Sun, Yanzhi

2010-01-15

A novel inorganic-organic composite material silica gel microspheres encapsulated by imidazole functionalized polystyrene (SG-PS-azo-IM) has been synthesized and characterized. This composite material was used to investigate the adsorption of Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II), Hg(II), Pb(II), Pd(II), Pt(II), Ag(I), and Au(III) from aqueous solutions, and the research results displayed that SG-PS-azo-IM has the highest adsorption capacity for Au(III). Langmuir and Freundlich isotherm models were applied to analyze the experimental data, the best interpretation for the experimental data was given by the Langmuir isotherm equation, and the maximum adsorption capacity for Au(III) is 1.700 mmol/g. The adsorption selectivity, the dynamic adsorption and desorption properties of SG-PS-azo-IM for Au(III) have also been studied. The results showed that SG-PS-azo-IM had excellent adsorption for Au(III) in four binary ions system, especially in the systems of Au(III)-Zn(II) and Au(III)-Cu(II), and almost Au(III) could be desorbed with the eluent solution of 0.5% thiourea in 1 mol/L HCl. Moreover, this novel composite material was used to preconcentrate Au(III) before its determination by flame atomic adsorption spectrometry. In the initial concentration range of 0.10-0.20 microg/mL, multiple of enrichment could reach 5.28. Thus, silica gel encapsulated by polystyrene coupling with imidazole (SG-PS-azo-IM) is favorable and useful for the removal of transition metal ions, and the high adsorption capacity makes it a good promising candidate material for Au(III) removal.

Systems approach to excitation-energy and electron transfer reaction networks in photosystem II complex: model studies for chlorophyll a fluorescence induction kinetics.

PubMed

Matsuoka, Takeshi; Tanaka, Shigenori; Ebina, Kuniyoshi

2015-09-07

Photosystem II (PS II) is a protein complex which evolves oxygen and drives charge separation for photosynthesis employing electron and excitation-energy transfer processes over a wide timescale range from picoseconds to milliseconds. While the fluorescence emitted by the antenna pigments of this complex is known as an important indicator of the activity of photosynthesis, its interpretation was difficult because of the complexity of PS II. In this study, an extensive kinetic model which describes the complex and multi-timescale characteristics of PS II is analyzed through the use of the hierarchical coarse-graining method proposed in the authors׳ earlier work. In this coarse-grained analysis, the reaction center (RC) is described by two states, open and closed RCs, both of which consist of oxidized and neutral special pairs being in quasi-equilibrium states. Besides, the PS II model at millisecond scale with three-state RC, which was studied previously, could be derived by suitably adjusting the kinetic parameters of electron transfer between tyrosine and RC. Our novel coarse-grained model of PS II can appropriately explain the light-intensity dependent change of the characteristic patterns of fluorescence induction kinetics from O-J-I-P, which shows two inflection points, J and I, between initial point O and peak point P, to O-J-D-I-P, which shows a dip D between J and I inflection points. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of the Manganese Cluster in Oxygen-Evolving Photosystem II with Distorted Cubane Manganese Compounds through X-ray Absorption Spectroscopy

PubMed Central

Cinco, Roehl M.; Rompel, Annette; Visser, Hendrik; Aromí, Guillem; Christou, George; Sauer, Kenneth; Klein, Melvin P.; Yachandra, Vittal K.

2014-01-01

X-ray absorption spectroscopy has been employed to assess the degree of similarity between the oxygen-evolving complex (OEC) in photosystem II (PS II) and a family of synthetic manganese complexes containing the distorted cubane [Mn4O3X] core (X = benzoate, acetate, methoxide, hydroxide, azide, fluoride, chloride, or bromide). These [Mn4(μ3-O)3(μ3-X)] cubanes possess C3v symmetry except for the X = benzoate species, which is slightly more distorted with only Cs symmetry. In addition, Mn4O3Cl complexes containing three or six terminal Cl ligands at three of the Mn were included in this study. The Mn K-edge X-ray absorption near edge structure (XANES) from the oxygen-ligated complexes begin to resemble general features of the PS II (S1 state) spectrum, although the second derivatives are distinct from those in PS II. The extended X-ray absorption fine structure (EXAFS) of these Mn compounds also displays superficial resemblance to that of PS II, but major differences emerge on closer examination of the phases and amplitudes. The most obvious distinction is the smaller magnitude of the Fourier transform (FT) of the PS II EXAFS compared to the FTs from the distorted cubanes. Curve fitting of the Mn EXAFS spectra verifies the known core structures of the Mn cubanes, and shows that the number of the crucial 2.7 and 3.3 Å Mn–Mn distances differs from that observed in the OEC. The EXAFS method detects small changes in the core structures as X is varied in this series, and serves to exclude the distorted cubane of C3v symmetry as a topological model for the Mn catalytic cluster of the OEC. Instead, the method shows that even more distortion of the cubane framework, altering the ratio of the Mn–Mn distances, is required to resemble the Mn cluster in PS II. PMID:11671305

Photoinhibition of Photosystems I and II Using Chlorophyll Fluorescence Measurements

ERIC Educational Resources Information Center

Quiles, Maria Jose

2005-01-01

In this study the photoinhibition of photosystems (PS) I and II caused by exposure to high intensity light in oat ("Avena sativa," var Prevision) is measured by the emission of chlorophyll fluorescence in intact leaves adapted to darkness. The maximal quantum yield of PS II was lower in plants grown under high light intensity than in plants grown…

Volume changes and electrostriction in the primary photoreactions of various photosynthetic systems: estimation of dielectric coefficient in bacterial reaction centers and of the observed volume changes with the Drude-Nernst equation.

PubMed

Mauzerall, David; Hou, Jian-Min; Boichenko, Vladimir A

2002-01-01

Photoacoustics (PA) allows the determination of enthalpy and volume changes of photoreactions in photosynthetic reaction centers on the 0.1-10 mus time scale. These include the bacterial centers from Rb. sphaeroides, PS I and PS II centers from Synechocystis and in whole cells. In vitro and in vivo PA data on PS I and PS II revealed that both the volume change (-26 A(3)) and reaction enthalpy (-0.4 eV) in PS I are the same as those in the bacterial centers. However the volume change in PS II is small and the enthalpy far larger, -1 eV. Assigning the volume changes to electrostriction allows a coherent explanation of these observations. One can explain the large volume decrease in the bacterial centers with an effective dielectric coefficient of approximately 4. This is a unique approach to this parameter so important in estimation of protein energetics. The value of the volume contraction for PS I can only be explained if the acceptor is the super- cluster (Fe(4)S(4))(Cys(4)) with charge change from -1 to -2. The small volume change in PS II is explained by sub-mus electron transfer from Y(Z) anion to P(680) cation, in which charge is only moved from the Y(Z) anion to the Q(A) with no charge separation or with rapid proton transfer from oxidized Y(Z) to a polar region and thus very little change in electrostriction. At more acid pH equally rapid proton transfer from a neighboring histidine to a polar region may be caused by the electric field of the P(680) cation.

Resolution and identification of the protein components of the photosystem II antenna system of higher plants by reversed-phase liquid chromatography with electrospray-mass spectrometric detection.

PubMed

Corradini, D; Huber, C G; Timperio, A M; Zolla, L

2000-07-21

Reversed-phase liquid chromatography (RPLC) was interfaced to mass spectrometry (MS) with an electrospray ion (ESI) source for the separation and accurate molecular mass determination of the individual intrinsic membrane proteins that comprise the photosystem II (PS II) major light-harvesting complex (LHC II) and minor (CP24, CP26 and CP29) antenna system, whose molecular masses range between 22,000 and 29,000. PS II is a supramolecular complex intrinsic of the thylacoid membrane, which plays the important role in photosynthesis of capturing solar energy, and transferring it to photochemical reaction centers where energy conversion occurs. The protein components of the PS II major and minor antenna systems were extracted from spinach thylacoid membranes and separated using a butyl-silica column eluted by an acetonitrile gradient in 0.05% (v/v) aqueous trifluoroacetic acid. On-line electrospray MS allowed accurate molecular mass determination and identification of the protein components of PS II major and minor antenna system. The proposed RPLC-ESI-MS method holds several advantages over sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the conventional technique for studying membrane proteins, including a better protein separation, mass accuracy, speed and efficiency.

Manganese-dependent carboanhydrase activity of photosystem II proteins.

PubMed

Shitov, A V; Pobeguts, O V; Smolova, T N; Allakhverdiev, S I; Klimov, V V

2009-05-01

Four sources of carbonic anhydrase (CA) activity in submembrane preparations of photosystem II (PS II) isolated from pea leaves were examined. Three of them belong to the hydrophilic proteins of the oxygen-evolving complex of PS II with molecular mass 33 kDa (protein PsbO), 24 kDa (protein PsbP), and 18 kDa (protein PsbQ). The fourth source of CA activity is associated with a pigment-protein complex of PS II after removing three hydrophilic proteins by salt treatment. Except for protein PsbQ, the CA activity of all these proteins depends on the presence of Mn2+: the purified protein PsbO did not show CA activity before adding Mn2+ into the medium (concentration of Mn2+ required for 50% effect, EC(50), was 670 microM); CA activity of protein mixture composed of PsbP and PsbQ increased more than 5-fold upon adding Mn2+ (EC(50) was 45 microM). CA activity of purified protein PsbP increased 2-fold in the presence of 200 microM Mn2+. As indicated for the mixture of two proteins (PsbP and PsbQ), Mg2+, Ca2+, and Zn2+, in contrast to Mn2+, suppressed CA activity (both initial and Mn2+-induced activity). Since the found sources of CA activity demonstrated properties different from ones of typical CA (need for Mn2+, insensitivity or low sensitivity to acetazolamide or ethoxyzolamide) and such CA activity was found only among PS II proteins, we cannot exclude that they belong to the type of Mn-dependent CA associated with PS II.

Angiotensin II stimulates basolateral 50-pS K channels in the thick ascending limb.

PubMed

Wang, Mingxiao; Luan, Haiyan; Wu, Peng; Fan, Lili; Wang, Lijun; Duan, Xinpeng; Zhang, Dandan; Wang, Wen-Hui; Gu, Ruimin

2014-03-01

We used the patch-clamp technique to examine the effect of angiotensin II (ANG II) on the basolateral K channels in the thick ascending limb (TAL) of the rat kidney. Application of ANG II increased the channel activity and the current amplitude of the basolateral 50-pS K channel. The stimulatory effect of ANG II on the K channels was completely abolished by losartan, an inhibitor of type 1 angiotensin receptor (AT1R), but not by PD123319, an AT2R antagonist. Moreover, inhibition of phospholipase C (PLC) and protein kinase C (PKC) also abrogated the stimulatory effect of ANG II on the basolateral K channels in the TAL. This suggests that the stimulatory effect of ANG II on the K channels was induced by activating PLC and PKC pathways. Western blotting demonstrated that ANG II increased the phosphorylation of c-Src at tyrosine residue 416, an indication of c-Src activation. This effect was mimicked by PKC stimulator but abolished by calphostin C. Moreover, inhibition of NADPH oxidase (NOX) also blocked the effect of ANG II on c-Src tyrosine phosphorylation. The role of Src-family protein tyrosine kinase (SFK) in mediating the effect of ANG II on the basolateral K channel was further suggested by the experiments in which inhibition of SFK abrogated the stimulatory effect of ANG II on the basolateral 50-pS K channel. We conclude that ANG II increases basolateral 50-pS K channel activity via AT1R and that activation of AT1R stimulates SFK by a PLC-PKC-NOX-dependent mechanism.

Optimizing COD removal from greywater by photoelectro-persulfate process using Box-Behnken design: assessment of effluent quality and electrical energy consumption.

PubMed

Ahmadi, Mehdi; Ghanbari, Farshid

2016-10-01

Greywater (GW) is a potential source for water reuse in various applications. However, GW treatment is still a vital issue in water reuse in cases of environmental standards and risk to public health. This study investigates optimization and modeling of a hybrid process for COD removal from GW. Persulfate (PS) was simultaneously activated by electrogenerated ferrous ion (EC) and UV to generate sulfate radical. Photoelectro-persulfate (PEPS) was optimized by Box-Behnken design and the effects of four variables (pH, PS dosage, current density, and electrolysis time) were evaluated on COD removal. The results and several coefficients showed that the obtained model was acceptable for predicting the COD removal. Moreover, under optimum conditions (pH = 6.9, PS = 8.8 mM, current density = 2.0 mA/cm(2), and 49.3 min electrolysis time), BOD5, turbidity, TSS, phosphate, and UV254 were effectively removed and COD and BOD5 values reached to discharge standards. Different configurations of the processes were assessed for COD removal. The order of COD removal efficiency followed: PS < Fe(II) < UV/PS ≤ Fe(II)/PS < Fe(II)/PS/UV < electrocoagulation ≤ electrocoagulation/UV < electro-PS < PEPS. The monitoring PS concentration during 60 min reaction time in the aforesaid processes indicated that PEPS could remarkably activate PS. The solution pH was also monitored and related results revealed that the presence of PS during the 10 min first time decreased pH value while production of hydroxide ion at cathode increased pH significantly. Finally, the contribution of electrochemical process in the electrical energy consumption was far less than that of photolysis process in hybrid PEPS process.

Design and Fabrication of High-Performance LWIR Photodetectors Based on Type-II Superlattices

DTIC Science & Technology

2017-08-11

SPONSOR/MONITOR’S REPORT Kirtland AFB, NM 87117-5776 NUMBER(S) AFRL -RV-PS-TR-2017-0090 12. DISTRIBUTION / AVAILABILITY STATEMENT Approved for public...unlimited. 13 DISTRIBUTION LIST DTIC/OCP 8725 John J. Kingman Rd, Suite 0944 Ft Belvoir, VA 22060-6218 1 cy AFRL /RVIL Kirtland AFB, NM 87117-5776 2... AFRL -RV-PS- AFRL -RV-PS- TR-2017-0090 TR-2017-0090 DESIGN AND FABRICATION OF HIGH- PERFORMANCE LWIR PHOTODETECTORS BASED ON TYPE-II SUPERLATTICES

The efficiency of non-photochemical fluorescence quenching by cation radicals in photosystem II reaction centers.

PubMed

Paschenko, V Z; Churin, A A; Gorokhov, V V; Grishanova, N P; Korvatovskii, B N; Maksimov, E G; Mamedov, M D

2016-12-01

In a direct experiment, the rate constants of photochemical k p and non-photochemical k p + quenching of the chlorophyll fluorescence have been determined in spinach photosystem II (PS II) membrane fragments, oxygen-evolving PS II core, as well as manganese-depleted PS II particles using pulse fluorimetry. In the dark-adapted reaction center(s) (RC), the fluorescence decay kinetics of the antenna were measured at low-intensity picosecond pulsed excitation. To create a "closed" P680 + Q A - state, RCs were illuminated by high-intensity actinic flash 8 ns prior to the measuring flash. The obtained data were approximated by the sum of two decaying exponents. It was found that the antennae fluorescence quenching efficiency by the oxidized photoactive pigment of RC P680 + was about 1.5 times higher than that of the neutral P680 state. These results were confirmed by a single-photon counting technique, which allowed to resolve the additional slow component of the fluorescence decay. Slow component was assigned to the charge recombination of P680 + Pheo - in PS II RC. Thus, for the first time, the ratio k p + /k p  ≅ 1.5 was found directly. The mechanism of the higher efficiency of non-photochemical quenching comparing to photochemical quenching is discussed.

Electronic readout system for the Belle II imaging Time-Of-Propagation detector

NASA Astrophysics Data System (ADS)

Kotchetkov, Dmitri

2017-07-01

The imaging Time-Of-Propagation (iTOP) detector, constructed for the Belle II experiment at the SuperKEKB e+e- collider, is an 8192-channel high precision Cherenkov particle identification detector with timing resolution below 50 ps. To acquire data from the iTOP, a novel front-end electronic readout system was designed, built, and integrated. Switched-capacitor array application-specific integrated circuits are used to sample analog signals. Triggering, digitization, readout, and data transfer are controlled by Xilinx Zynq-7000 system on a chip devices.

Miniaturized Retrodirective Arrays for a Nanosatellite Platform

DTIC Science & Technology

2012-01-01

TABLE I ABBREVIATED CONTROL MODULE LOOKUP TABLE PS2 PS3 PS4 e B4 B3 82 81 84 83 82 81 84 83 82 81 30.00 1 1 0 0 I 0 0 0 0 I 0 0 22.02 l l 0 1 l 0 I...is controlled by bit values in columns PS2, PS3 , and PS4 of Table I. 4.3.2 Experimental Results Full-Duplex Operation To show the full-duplex

Redox potential of pheophytin a in photosystem II of two cyanobacteria having the different special pair chlorophylls.

PubMed

Allakhverdiev, Suleyman I; Tomo, Tatsuya; Shimada, Yuichiro; Kindo, Hayato; Nagao, Ryo; Klimov, Vyacheslav V; Mimuro, Mamoru

2010-02-23

Water oxidation by photosystem (PS) II in oxygenic photosynthetic organisms is a major source of energy on the earth, leading to the production of a stable reductant. Mechanisms generating a high oxidation potential for water oxidation have been a major focus of photosynthesis research. This potential has not been estimated directly but has been measured by the redox potential of the primary electron acceptor, pheophytin (Phe) a. However, the reported values for Phe a are still controversial. Here, we measured the redox potential of Phe a under physiological conditions (pH 7.0; 25 degrees C) in two cyanobacteria with different special pair chlorophylls (Chls): Synechocystis sp. PCC 6803, whose special pair for PS II consists of Chl a, and Acaryochloris marina MBIC 11017, whose special pair for PS II consists of Chl d. We obtained redox potentials of -536 +/- 8 mV for Synechocystis sp. PCC 6803 and -478 +/- 24 mV for A. marina on PS II complexes in the presence of 1.0 M betaine. The difference in the redox potential of Phe a between the two species closely corresponded with the difference in the light energy absorbed by Chl a versus Chl d. We estimated the potentials of the special pair of PS II to be 1.20 V and 1.18 V for Synechocystis sp. PCC 6803 (P680) and A. marina (P713), respectively. This clearly indicates conservation in the properties of water-oxidation systems in oxygenic photosynthetic organisms, irrespective of the special-pair chlorophylls.

Intrinsic polarization switching in BaTi O3 crystal under uniaxial electromechanical loading

NASA Astrophysics Data System (ADS)

Li, Yingwei; Wang, Jie; Li, Faxin

2016-11-01

Both 180∘ and 90∘ intrinsic polarization switching (IPS) in BaTi O3 crystal were investigated by Landau-Ginzburg-Devonshire (LGD) theory under combined electric field and stress loading. Results show that for 180∘PS , the coercive electric field (EIC 180∘) increases under tension but decreases under compression with increasing stresses. The 90∘PS was classified into two types. For type I 90∘PS , EIC I (90∘) increases under tension but decreases under compression with increasing stresses, similar to 180∘PS ; while for type II 90∘PS , an opposite variation trend is observed. (The definition of the type I and the type II 90∘PS is given in the text.) Additionally, the calculation demonstrates that under tensile stresses or under compressive stresses between -140 and 0 MPa, the electric field needed to drive both types of 90∘PS is smaller than that needed for driving 180∘PS , implying that 180∘PS is favorable to accomplish by two-step 90∘PS . As EI C refers to 180∘PS in the past investigations, these demonstrate that the EI C calculated by others may be overestimated. Moreover, the coercive stresses needed to drive 90∘ ferroelastic IPS was also calculated as a function of preloading bias electric fields.

GPS PPP-derived precipitable water vapor retrieval based on Tm/Ps from multiple sources of meteorological data sets in China

NASA Astrophysics Data System (ADS)

Zhang, Hongxing; Yuan, Yunbin; Li, Wei; Ou, Jikun; Li, Ying; Zhang, Baocheng

2017-04-01

Weighted mean temperature (Tm) and pressure (Ps) are two parameters of great relevance to precipitable water vapor (PWV) retrieval from global positioning system (GPS) data. However, information about the Tm and Ps cannot be available for those GPS stations that are not colocated with meteorological sensors. To investigate the optimal GPS-PWV retrieval method for China, two enhanced Tm models, GM-Tm (temperature dependent) and GH-Tm (temperature independent), are developed. Additionally, the potentials of the Ps data from the two reanalysis data sets, the National Centers for Environmental Prediction (NCEP)-Department of Energy (DOE) Reanalysis II (NCEP II) and ERA-Interim, and from the empirical model GPT2w for GPS-PWV retrieval are investigated over China. To evaluate the performances of multisources Tm and Ps data for GPS-PWV retrieval, GPS data (2011-2013) collected from 22 stations of the Crustal Movement Observation Network of China (CMONOC) were processed by using the precise point positioning (PPP) technique, estimating the zenith tropospheric delay (ZTD) so as to be subsequently converted to GPS-PWV. The retrieved GPS-PWVs are compared with their counterparts derived from NCEP II and radiosonde data over China. The results show that (1) the GM-Tm model consistently shows the highest accuracy (with root mean square error of 2.3 K), and the GH-Tm model should be selected when temperature observations are not available, and that (2) the performances of Ps from NCEP II and ERA-Interim differ marginally for GPS-PWV retrieval, and significant seasonal variations are found in the agreement between the GPS-PWVs and the PWVs derived from NCEP II and radiosonde data over China.

Photodamage of a Mn(III/IV)-oxo mixed-valence compound and photosystem II: evidence that a high-valent manganese species is responsible for UV-induced photodamage of the oxygen-evolving complex in photosystem II.

PubMed

Wei, Zi; Cady, Clyde W; Brudvig, Gary W; Hou, Harvey J M

2011-01-01

The Mn cluster in photosystem II (PS II) is believed to play an important role in the UV photoinhibition of green plants, but the mechanism is still not clear at a molecular level. In this work, the photochemical stability of [Mn(III)(O)(2)Mn(IV)(H(2)O)(2)(Terpy)(2)](NO(3))(3) (Terpy=2,2':6',2''-terpyridine), designated as Mn-oxo mixed-valence dimer, a well characterized functional model of the oxygen-evolving complex in PS II, was examined in aqueous solution by exposing the complex to excess light irradiation at six different wavelengths in the range of 250 to 700 nm. The photodamage of the Mn-oxo mixed-valence dimer was confirmed by the decrease of its oxygen-evolution activity measured in the presence of the chemical oxidant oxone. Ultraviolet light irradiation induced a new absorption peak at around 400-440 nm of the Mn-oxo mixed-valence dimer. Visible light did not have the same effect on the Mn-oxo mixed-valence dimer. We speculate that the spectral change may be caused by conversion of the Mn(III)O(2)Mn(IV) dimer into a new structure--Mn(IV)O(2)Mn(IV). In the processes, the appearance of a 514 nm fluorescence peak was observed in the solution and may be linked to the hydration or protonation of Terpy ligand in the Mn-oxo dimer. In comparing the response of the PS II functional model compound and the PS II complex to excess light radiation, our results support the idea that UV photoinhibition is triggered at the Mn(4)Ca center of the oxygen-evolution complex in PS II by forming a modified structure, possibly a Mn(IV) species, and that the reaction of Mn ions is likely the initial step. Published by Elsevier B.V.

Association between presenilin-1 polymorphism and maternal meiosis II errors in Down syndrome.

PubMed

Petersen, M B; Karadima, G; Samaritaki, M; Avramopoulos, D; Vassilopoulos, D; Mikkelsen, M

2000-08-28

Several lines of evidence suggest a shared genetic susceptibility to Down syndrome (DS) and Alzheimer disease (AD). Rare forms of autosomal-dominant AD are caused by mutations in the APP and presenilin genes (PS-1 and PS-2). The presenilin proteins have been localized to the nuclear membrane, kinetochores, and centrosomes, suggesting a function in chromosome segregation. A genetic association between a polymorphism in intron 8 of the PS-1 gene and AD has been described in some series, and an increased risk of AD has been reported in mothers of DS probands. We therefore studied 168 probands with free trisomy 21 of known parental and meiotic origin and their parents from a population-based material, by analyzing the intron 8 polymorphism in the PS-1 gene. An increased frequency of allele 1 in mothers with a meiosis II error (70.8%) was found compared with mothers with a meiosis I error (52.7%, P < 0.01), with an excess of the 11 genotype in the meiosis II mothers. The frequency of allele 1 in mothers carrying apolipoprotein E (APOE) epsilon4 allele (68.0%) was higher than in mothers without epsilon4 (52.2%, P < 0.01). We hypothesize that the PS-1 intronic polymorphism might be involved in chromosomal nondisjunction through an influence on the expression level of PS-1 or due to linkage disequilibrium with biologically relevant polymorphisms in or outside the PS-1 gene. Copyright 2000 Wiley-Liss, Inc.

ACTIVATION OF EXTRACELLULAR REGULATED KINASE AND MECHANISTIC TARGET OF RAPAMYCIN PATHWAY IN FOCAL CORTICAL DYSPLASIA

PubMed Central

Patil, Vinit V.; Guzman, Miguel; Carter, Angela N.; Rathore, Geetanjali; Yoshor, Daniel; Curry, Daniel; Wilfong, Angus; Agadi, Satish; Swann, John W.; Adesina, Adekunle M.; Bhattacharjee, Meenakshi B.; Anderson, Anne E.

2016-01-01

Neuropathology of resected brain tissue has revealed an association of focal cortical dysplasia (FCD) with drug resistant epilepsy (DRE). Recent studies have shown that the mechanistic target of rapamycin (mTOR) pathway is hyperactivated in FCD as evidenced by increased phosphorylation of the ribosomal protein S6 (S6) at serine 240/244 (S240/244), a downstream target of mTOR. Moreover, extracellular regulated kinase (ERK) has been shown to phosphorylate S6 at serine 235/236 (S235/236) and tuberous sclerosis complex 2 (TSC2) at serine 664 (S664) leading to hyperactive mTOR signaling. We evaluated ERK phosphorylation of S6 and TSC2 in two types of FCD (FCD I and FCDII) as a candidate mechanism contributing to mTOR pathway dysregulation in this disorder. Tissue samples from patients with tuberous sclerosis (TS) served as a positive control. Immunostaining for phospho-S6 (pS6240/244 and pS6235/236), phospho-ERK (pERK), and phospho-TSC2 (pTSC2) was performed on resected brain tissue with FCD and TS. We found increased pS6240/244 and pS6235/236 staining in FCD I, FCD II, and TS compared to normal appearing tissue, while pERK and pTSC2 staining was increased only in FCD IIb and TS tissue. Our results suggest that both the ERK and mTOR pathways are dysregulated in FCD and TS; however, the signaling alterations are different for FCD I as compared to FCD II and TS. PMID:26381727

Evaluation of magnifying colonoscopy in the diagnosis of serrated polyps.

PubMed

Ishigooka, Shinya; Nomoto, Masahito; Obinata, Nobuyuki; Oishi, Yoshichika; Sato, Yoshinori; Nakatsu, Satoko; Suzuki, Midori; Ikeda, Yoshiko; Maehata, Tadateru; Kimura, Tomoaki; Watanabe, Yoshiyuki; Nakajima, Takashi; Yamano, Hiro-o; Yasuda, Hiroshi; Itoh, Fumio

2012-08-28

To elucidate the colonoscopic features of serrated lesions of the colorectum using magnifying colonoscopy. Broad division of serrated lesions of the colorectum into hyperplastic polyps (HPs), traditional serrated adenomas (TSAs), and sessile serrated adenomas/polyps (SSA/Ps) has been proposed on the basis of recent molecular biological studies. However, few reports have examined the colonoscopic features of these divisions, including magnified colonoscopic findings. This study examined 118 lesions excised in our hospital as suspected serrated lesions after magnified observation between January 2008 and September 2011. Patient characteristics (sex, age), conventional colonoscopic findings (location, size, morphology, color, mucin) and magnified colonoscopic findings (pit pattern diagnosis) were interpreted by five colonoscopists with experience in over 1000 colonoscopies, and were compared with histopathological diagnoses. The pit patterns were categorized according to Kudo's classification, but a more detailed investigation was also performed using the subclassification [type II-Open (type II-O), type II-Long (type II-L), or type IV-Serrated (type IV-S)] proposed by Kimura T and Yamano H. Lesions comprised 23 HPs (23/118: 19.5%), 39 TSAs (39/118: 33.1%: with cancer in one case), 50 SSA/Ps (50/118: 42.4%: complicated with cancer in three cases), and six others (6/118: 5.1%). We excluded six others, including three regular adenomas, one hamartoma, one inflammatory polyp, and one juvenile polyp for further analysis. Conventional colonoscopy showed that SSA/Ps were characterized as larger in diameter than TSAs and HPs (SSA/P vs HP, 13.62 ± 8.62 mm vs 7.74 ± 3.24 mm, P < 0.001; SSA/Ps vs TSA, 13.62 ± 8.62 mm vs 9.89 ± 5.73 mm, P < 0.01); common in the right side of the colon [HPs, 30.4% (7/23): TSAs, 20.5% (8/39): SSA/P, 84.0% (42/50), P < 0.001]; flat-elevated lesion [HPs, 30.4% (7/23): TSAs, 5.1% (2/39): SSA/Ps, 90.0% (45/50), P < 0.001]; normal-colored or pale imucosa [HPs, 34.8% (8/23): TSAs, 10.3% (4/39): SSA/Ps, 80% (40/50), P < 0.001]; and with large amounts of mucin [HPs, 21.7% (5/23): TSAs, 17.9% (7/39): SSA/Ps, 72.0% (36/50), P < 0.001]. In magnified colonoscopic findings, 17 lesions showed either type II pit pattern alone or partial type II pit pattern as the basic architecture, with 14 HPs (14/17, 70.0%) and 3 SSA/Ps. Magnified colonoscopy showed the type II-O pit pattern as characteristic of SSA/Ps [sensitivity 83.7% (41/49), specificity 85.7% (54/63)]. Cancer was also present in three lesions, in all of which a type VI pit pattern was also present within the same lesion. There were four HPs and four TSAs each. The type IV-S pit pattern was characteristic of TSAs [sensitivity 96.7% (30/31), specificity 89.9% (72/81)]. Cancer was present in one lesion, in which a type VI pit pattern was also present within the same lesion. In our study, serrated lesions of the colorectum also possessed the features described in previous reports of conventional colonoscopic findings. The pit pattern diagnosis using magnifying colonoscopy, particularly magnified colonoscopic findings using subclassifications of surface architecture, reflected the pathological characteristics of SSA/Ps and TSAs, and will be useful for colonoscopic diagnosis. We suggest that this system could be a good diagnostic tool for SSA/Ps using magnifying colonoscopy.

Lower neurocognitive function in U-2 pilots

PubMed Central

Tate, David F.; Wood, Joe; Sladky, John H.; McDonald, Kent; Sherman, Paul M.; Kawano, Elaine S.; Rowland, Laura M.; Patel, Beenish; Wright, Susan N.; Hong, Elliot; Rasmussen, Jennifer; Willis, Adam M.; Kochunov, Peter V.

2014-01-01

Objective: Determine whether United States Air Force (USAF) U-2 pilots (U2Ps) with occupational exposure to repeated hypobaria had lower neurocognitive performance compared to pilots without repeated hypobaric exposure and whether U2P neurocognitive performance correlated with white matter hyperintensity (WMH) burden. Methods: We collected Multidimensional Aptitude Battery–II (MAB-II) and MicroCog: Assessment of Cognitive Functioning (MicroCog) neurocognitive data on USAF U2Ps with a history of repeated occupational exposure to hypobaria and compared these with control data collected from USAF pilots (AFPs) without repeated hypobaric exposure (U2Ps/AFPs MAB-II 87/83; MicroCog 93/80). Additional comparisons were performed between U2Ps with high vs low WMH burden. Results: U2Ps with repeated hypobaric exposure had significantly lower scores than control pilots on reasoning/calculation (U2Ps/AFPs 99.4/106.5), memory (105.5/110.9), information processing accuracy (102.1/105.8), and general cognitive functioning (103.5/108.5). In addition, U2Ps with high whole-brain WMH count showed significantly lower scores on reasoning/calculation (high/low 96.8/104.1), memory (102.9/110.2), general cognitive functioning (101.5/107.2), and general cognitive proficiency (103.6/108.8) than U2Ps with low WMH burden (high/low WMH mean volume 0.213/0.003 cm3 and mean count 14.2/0.4). Conclusion: In these otherwise healthy, highly functioning individuals, pilots with occupational exposure to repeated hypobaria demonstrated lower neurocognitive performance, albeit demonstrable on only some tests, than pilots without repeated exposure. Furthermore, within the U2P population, higher WMH burden was associated with lower neurocognitive test performance. Hypobaric exposure may be a risk factor for subtle changes in neurocognition. PMID:25008397

Benefits Analysis Of Alternative Secondary National Ambient ...

EPA Pesticide Factsheets

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Increases in plasma plant sterols stabilize within four weeks of plant sterol intake and are independent of cholesterol metabolism.

PubMed

Ras, R T; Koppenol, W P; Garczarek, U; Otten-Hofman, A; Fuchs, D; Wagner, F; Trautwein, E A

2016-04-01

Plant sterols (PS) lower plasma LDL-cholesterol through partial inhibition of intestinal cholesterol absorption. Although PS themselves are poorly absorbed, increased intakes of PS result in elevated plasma concentrations. In this paper, we report time curves of changes in plasma PS during 12 weeks of PS intake. Furthermore, the impact of cholesterol synthesis and absorption on changes in plasma PS is explored. The study was a double-blind, randomized, placebo-controlled, parallel-group study with the main aim to investigate the effects of PS on vascular function (clinicaltrials.gov: NCT01803178). Hypercholesterolemic but otherwise healthy men and women (n = 240) consumed low-fat spreads without or with added PS (3 g/d) for 12 weeks after a 4-week run-in period. Blood sampling was performed at week 0, 4, 8 and 12. Basal cholesterol-standardized concentrations of lathosterol and sitosterol + campesterol were used as markers of cholesterol synthesis and absorption, respectively. In the PS group, plasma sitosterol and campesterol concentrations increased within the first 4 weeks of intervention by 69% (95%CI: 58; 82) starting at 7.2 μmol/L and by 28% (95%CI: 19; 39) starting at 11.4 μmol/L, respectively, and remained stable during the following 8 weeks. Placebo-corrected increases in plasma PS were not significantly different between high and low cholesterol synthesizers (P-values >0.05). Between high and low cholesterol absorbers, no significant differences were observed, except for the cholesterol-standardized sum of four major plasma PS (sitosterol, campesterol, brassicasterol and stigmasterol) showing larger increases in low absorbers (78.3% (95%CI: 51.7; 109.5)) compared to high absorbers (40.8% (95%CI: 19.9; 65.5)). Increases in plasma PS stabilize within 4 weeks of PS intake and do not seem impacted by basal cholesterol synthesis or absorption efficiency. This study was registered at clinicaltrials.gov (NCT01803178). Copyright © 2015 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Body-image, quality of life and psychological distress: a comparison between kidney transplant patients and a matching healthy sample.

PubMed

Yagil, Yaron; Geller, Shulamit; Levy, Sigal; Sidi, Yael; Aharoni, Shiri

2018-04-01

The purpose of the current study was to assess the uniqueness of the condition of kidney transplant recipients in comparison to a sample of matching healthy peers in relation to body-image dissatisfaction and identification, quality of life and psychological distress. Participants were 45 kidney transplant recipients who were under follow-up care at a Transplant Unit of a major Medical Center, and a sample of 45 matching healthy peers. Measures were taken using self-report questionnaires [Body-Image Ideals Questionnaire (BIIQ), Body Identification Questionnaire (BIQ), Brief Symptoms Inventory (BSI), and the SF-12]. The major findings were the following: (i) kidney transplant recipients reported lower levels of quality of life and higher levels of PsD when compared to their healthy peers; (ii) no difference in body-image dissatisfaction was found between the two studied groups; (iii) significant correlations between body-image dissatisfaction quality of life and PsD were found only in the kidney transplant recipients. The kidney transplantation condition has a moderating effect in the association between body-image dissatisfaction PsD but not in the association between body-image dissatisfaction and quality of life; (iv) kidney transplant recipients experienced higher levels of body identification than did their healthy peers. Taken together, these findings highlight the unique condition of kidney transplant recipients, as well as the function that body-image plays within the self.

[Effects of plastic film mulching and rain harvesting modes on chlorophyll fluorescence characteristics, yield and water use efficiency of dryland maize].

PubMed

Li, Shang-Zhong; Fan, Ting-Lu; Wang, Yong; Zhao, Gang; Wang, Lei; Tang, Xiao-Ming; Dang, Yi; Zhao, Hui

2014-02-01

The differences on chlorophyll fluorescence parameters, yield and water use efficiency of dryland maize were compared among full plastic film mulching on double ridges and planting in catchment furrows (FFDRF), half plastic film mulching on double ridges and planting in catchment furrows (HFDRF), plastic film mulching on ridge and planting in film-side (FS), and flat planting with no plastic film mulching (NM) under field conditions in dry highland of Loess Plateau in 2007-2012. The results showed that fluorescence yield (Fo), the maximum fluorescence yield (Fm), light-adapted fluorescence yield when PS II reaction centers were totally open (F), light-adapted fluorescence yield when PS II reaction centers closed (Fm'), the maximal photochemical efficiency of PS II (Fv/Fm), the actual photochemical efficiency of PS II in the light (Phi PS II), the relative electron transport rate (ETR), photochemical quenching (qP) and non-photochemical quenching (qN) in maize leaves of FFDRF were higher than that of control (NM), and the value of 1-qP was lower than that of control, at 13:00, chlorophyll fluorescence parameters values of FFDRF was significantly higher than control, which were increased by 5.3%, 56.8%, 10.7%, 36.3%, 23.6%, 56.7%, 64.4%, 45.5%, 23.6% and -55.6%, respectively, compared with the control. Yield and water use efficiency of FFDRF were the highest in every year no matter dry year, normal year, humid year and hail disaster year. Average yield and water use efficiency of FFDRF were 12,650 kg x hm(-2) and 40.4 kg x mm(-1) x hm(-2) during 2007-2012, increased by 57.8% and 61.6% compared with the control, respectively, and also significantly higher compared with HFDRF and PS. Therefore, it was concluded that FFDRF had significantly increased the efficiency of light energy conversion and improved the production capacity of dryland maize.

Generation of a Mn(IV)-Peroxo or Mn(III)-Oxo-Mn(III) Species upon Oxygenation of Mono- and Binuclear Thiolate-Ligated Mn(II) Complexes.

PubMed

Lee, Chien-Ming; Wu, Wun-Yan; Chiang, Ming-Hsi; Bohle, D Scott; Lee, Gene-Hsiang

2017-09-05

A thiolate-bridged binuclear complex [PPN] 2 [(Mn II ( TMS PS3)) 2 ] (1, PPN = bis(triphenylphosphine)iminium and TMS PS3H 3 = (2,2',2″-trimercapto-3,3',3″-tris(trimethylsilyl)triphenylphosphine)), prepared from the reaction of MnCl 2 /[PPN]Cl and Li 3 [ TMS PS3], converts into a mononuclear complex [PPN][Mn II ( TMS PS3)(DABCO)] (2) in the presence of excess amounts of DABCO (DABCO = 1,4-diazabicyclo[2.2.2]octane). Variable temperature studies of solution containing 1 and DABCO by UV-vis spectroscopy indicate that 1 and 2 exist in significant amounts in equilibrium and mononuclear 2 is favored at low temperature. Treatment of 1 or 2 with the monomeric O 2 -side-on-bound [PPN][Mn IV (O 2 )( TMS PS3)] (3) produces the mono-oxo-bridged dimer [PPN] 2 [(Mn III ( TMS PS3)) 2 (μ-O)] (4). The electrochemistry of 1 and 2 reveals anodic peak(s) for a Mn III/ Mn II redox couple at shifted potentials against Fc/Fc + , indicating that both complexes can be oxidized by dioxygen. The O 2 activation mediated by 1 and 2 is investigated in both solution and the solid state. Microcrystals of 2 rapidly react with air or dry O 2 to generate the Mn(IV)-peroxo 3 in high yield, revealing a solid-to-solid transformation and two-electron reduction of O 2 . Oxygenation of 1 or 2 in solution, however, is affected by diffusion and transient concentration of dioxygen in the two different substrates, leading to generation of 3 and 4 in variable ratios.

Testing directed evolution strategies for space exploration: genetic modification of photosystem II to increase stress tolerance under space conditions

NASA Astrophysics Data System (ADS)

Bertalan, I.; Giardi, M. T.; Johanningmeier, U.

Plants and many microorganisms are able to convert and store solar energy in chemical bonds by a process called photosynthesis They remove CO 2 from the atmosphere fix it as carbohydrate and simultaneously evolve oxygen Oxygen evolution is of supreme relevance for all higher life forms and results from the splitting of water molecules This process is catalyzed by the so called photosystem II PSII complex and represents the very beginning of biomass production PS II is also a central point of regulation being responsive to various physical and physiological parameters Complex space radiation is damaging PS II and reduces photosynthetic efficiency Thus bioregenerative life-support systems are severely disturbed at this point Genetic manipulation of photosynthesis checkpoints offer the possibility to adjust biomass and oxygen production to changing environmental conditions As the photosynthetic apparatus has adapted to terrestrial and not to space conditions we are trying to adapt a central and particularly stress-susceptible element of the photosynthesis apparatus - the D1 subunit of PS II - to space radiation by a strategy of directed evolution The D1 subunit together with its sister subunit D2 form the reaction centre of PS II D1 presents a central weak point for radiation energy that hits the chloroplast We have constructed a mutant of the green alga Chlamydomonas reinhardtii with a defect D1 protein This mutant is easily transformable with D1-encoding PCR fragments without purification and cloning steps 1 When

Fertilization Induces a Transient Exposure of Phosphatidylserine in Mouse Eggs

PubMed Central

Curia, Claudio A.; Ernesto, Juan I.; Stein, Paula; Busso, Dolores; Schultz, Richard M.; Cuasnicu, Patricia S.; Cohen, Débora J.

2013-01-01

Phosphatidylserine (PS) is normally localized to the inner leaflet of the plasma membrane and the requirement of PS translocation to the outer leaflet in cellular processes other than apoptosis has been demonstrated recently. In this work we investigated the occurrence of PS mobilization in mouse eggs, which express flippase Atp8a1 and scramblases Plscr1 and 3, as determined by RT-PCR; these enzyme are responsible for PS distribution in cell membranes. We find a dramatic increase in binding of flouresceinated-Annexin-V, which specifically binds to PS, following fertilization or parthenogenetic activation induced by SrCl2 treatment. This increase was not observed when eggs were first treated with BAPTA-AM, indicating that an increase in intracellular Ca2+ concentration was required for PS exposure. Fluorescence was observed over the entire egg surface with the exception of the regions overlying the meiotic spindle and sperm entry site. PS exposure was also observed in activated eggs obtained from CaMKIIγ null females, which are unable to exit metaphase II arrest despite displaying Ca2+ spikes. In contrast, PS exposure was not observed in TPEN-activated eggs, which exit metaphase II arrest in the absence of Ca2+ release. PS exposure was also observed when eggs were activated with ethanol but not with a Ca2+ ionophore, suggesting that the Ca2+ source and concentration are relevant for PS exposure. Last, treatment with cytochalasin D, which disrupts microfilaments, or jasplakinolide, which stabilizes microfilaments, prior to egg activation showed that PS externalization is an actin-dependent process. Thus, the Ca2+ rise during egg activation results in a transient exposure of PS in fertilized eggs that is not associated with apoptosis. PMID:23951277

Effects of electrolysis by low-amperage electric current on the chlorophyll fluorescence characteristics of Microcystis aeruginosa.

PubMed

Lin, Li; Feng, Cong; Li, Qingyun; Wu, Min; Zhao, Liangyuan

2015-10-01

Effects of electrolysis by low-amperage electric current on the chlorophyll fluorescence characteristics of Microcystis aeruginosa were investigated in order to reveal the mechanisms of electrolytic inhibition of algae. Threshold of current density was found under a certain initial no. of algae cell. When current density was equal to or higher than the threshold (fixed electrolysis time), growth of algae was inhibited completely and the algae lost the ability to survive. Effect of algal solution volume on algal inhibition was insignificant. Thresholds of current density were 8, 10, 14, 20, and 22 mA cm(-2) at 2.5 × 10(7), 5 × 10(7), 1 × 10(8), 2.5 × 10(8), and 5 × 10(8) cells mL(-1) initial no. of algae cell, respectively. Correlativity between threshold of current and initial no. of algae cells was established for scale-up and determining operating conditions. Changes of chlorophyll fluorescence parameters demonstrated that photosystem (PS) II of algae was damaged by electrolysis but still maintained relatively high activity when algal solution was treated by current densities lower than the threshold. The activity of algae recovered completely after 6 days of cultivation. On the contrary, when current density was higher than the threshold, connection of phycobilisome (PBS) and PS II core complexes was destroyed, PS II system of algae was damaged irreversibly, and algae could not survive thoroughly. The inactivation of M. aeruginosa by electrolysis can be attributed to irreversible separation of PBS from PS II core complexes and the damage of PS II of M. aeruginosa.

Decreased Bacterial Diversity Characterizes an Altered Gut Microbiota in Psoriatic Arthritis and Resembles Dysbiosis of Inflammatory Bowel Disease

PubMed Central

Scher, Jose U.; Ubeda, Carles; Artacho, Alejandro; Attur, Mukundan; Isaac, Sandrine; Reddy, Soumya M.; Marmon, Shoshana; Neimann, Andrea; Brusca, Samuel; Patel, Tejas; Manasson, Julia; Pamer, Eric G.; Littman, Dan R.; Abramson, Steven B.

2014-01-01

Objective To characterize the diversity and taxonomic relative abundance of the gut microbiota in patients with never-treated, recent-onset psoriatic arthritis (PsA). Methods High-throughput 16S rRNA pyrosequencing was utilized to compare community composition of gut microbiota in PsA patients (n=16), subjects with psoriasis of the skin (Ps) (n=15) and healthy, matched-controls (n=17). Samples were further assessed for the presence and levels of fecal and serum secretory immunoglobulin A (sIgA), pro-inflammatory proteins and fatty-acids. Results The gut microbiota observed in PsA and Ps patients was less diverse when compared to healthy controls. These could be attributed to the reduced presence of several taxa. While both groups showed a relative decrease in Coprococcus spp., PsA samples were characterized by a significant reduction in Akkermansia, Ruminococcus, and Pseudobutyrivibrio. Supernatants of fecal samples from PsA patients revealed an increase in sIgA and a decrease in receptor activator of nuclear factor kappa-B ligand (RANKL) levels. Fatty acid analysis revealed low levels of hexanoate and heptanoate in PsA and Ps patients. Conclusion PsA and Ps patients had a lower relative abundance of multiple intestinal bacteria. Although some genera were concomitantly decreased in both conditions, PsA samples had lower abundance of reportedly beneficial taxa. This gut microbiota profile in PsA was similar to that published for patients with IBD and was associated with changes in specific inflammatory proteins unique to this group, and distinct from Ps and controls. Thus, the role of gut microbiota in the continuum of Ps-PsA pathogenesis and the associated immune response merits further study. PMID:25319745

Incorporation of preservatives in polylactic acid films for inactivating Escherichia coli O157:H7 and extending microbiological shelf life of strawberry puree.

PubMed

Jin, Tony; Zhang, Howard; Boyd, Glenn

2010-05-01

Antimicrobial films of polylactic acid polymer incorporated with nisin, EDTA, sodium benzoate (SB), potassium sorbate (PS), and their combinations were developed, and their antimicrobial effects on the inactivation of Escherichia coli O157:H7 and natural background microflora (total aerobic bacteria, molds, and yeasts) in strawberry puree at 10 and 22 degrees C were determined. Direct addition of SB+PS to strawberry puree was also used as a comparison with SB+PS film treatment. The combination treatment reduced the cell populations of E. coli O157:H7 from 3.5 log CFU/ml to undetectable levels (<1 CFU/ml) after 14 days and 1 day at 10 and 22 degrees C, respectively, while the cells of E. coli O157:H7 in control samples survived up to 48 days at 10 degrees C and more than 14 days at 22 degrees C. The SB+PS film treatment produced a greater reduction of population of E. coli O157:H7 cells than did the SB+PS direct addition treatment. Similar results were observed for inactivation of natural microflora. In general, the antimicrobial effect was in the following order: film combination > SB+PS film > SB+PS direct addition > EDTA film > nisin film. The data obtained in this study suggest two approaches toward the development of control interventions against E. coli O157:H7 and extension of the microbiological shelf life of strawberry puree: (i) using antimicrobial packaging and (ii) using combinations of preservatives. The film formulas developed here can be used to make bottles or as coatings on the surface of bottles for use in liquid food packaging.

Biotic stress induced demolition of thylakoid structure and loss in photoelectron transport of chloroplasts in papaya leaves.

PubMed

Nanda, Rashmi Madhumita; Biswal, Basanti

2008-04-01

Papaya mosaic virus (PMV) causes severe mosaic symptoms in the papaya (Carica papaya L.) leaves. The PMV-induced alterations in photosystem II (PS II) structure and photochemical functions were probed. An increase in chlorophyll a (Chl a) fluorescence polarization suggests pathogen-induced transformation of thylakoid membrane to a gel phase. This transformation in physical state of thylakoid membrane may result in alteration in topology of pigments on pigment-binding proteins as reflected in pathogen-induced loss in the efficiency of energy transfer from carotenoids to chlorophylls. The fast Chl a fluorescence induction kinetics of healthy and PMV-infected plants by F(O)-F(J)-F(I)-F(P) transients revealed pathogen-induced perturbation on PS II acceptor side electron transfer equilibrium between Q(A) and Q(B) and in the pool size of electron transport acceptors. Pathogen-induced loss in photosynthetic pigments, changes in thylakoid structure and decrease in the ratio of F(V)/F(M) (photochemical potential of PS II) further correlate with the loss in photoelectron transport of PS II as probed by 2,6-dichlorophenol indophenol (DCPIP)-Hill reaction. Restoration of the loss by 1,5-diphenyl carbazide (DPC), an exogenous electron donor, that donates electron directly to reaction centre II bypassing the oxygen evolving system (OES), leads towards the conclusion that OES is one of the major targets of biotic stress. Further, the data suggest that chlorophyll fluorescence could be used as a non-invasive handy tool to assess the loss in photosynthetic efficiency and symptom severity in infected green tissues vis-a-vis the healthy ones.

[Effects of acid rain stress on Eleocarpus glabripetalus seedlings leaf chlorophyll fluorescence characteristics and growth].

PubMed

Yin, Xiu-Min; Yu, Shu-Quan; Jiang, Hong; Liu, Mei-Hu

2010-06-01

A pot experiment was conducted to study the Eleocarpus glabripetalus seedlings leaf chlorophyll fluorescence characteristics and growth in different seasons under simulated acid rain stress (heavy, pH = 2. 5; moderate, pH = 4.0; and control, pH = 5.6). In the same treatments, the leaf relative chlorophyll content (SPAD), maximum PS II photochemical efficiency (F(v)/F(m)), actual PSII photochemical quantum yield (phi(PS II)), plant height, and stem diameter in different seasons were all in the order of October > July > April > January. In the same seasons, all the parameters were in the order of heavy acid rain > moderate acid rain > control. The interactions between different acid rain stress and seasons showed significant effects on the SPAD, F(v)/F(m), plant height, and stem diameter, but lesser effects on phi(PS II), qp and qN.

Functional characterization of mutant strains of the cyanobacterium Synechocystis sp. PCC 6803 lacking short domains within the large, lumen-exposed loop of the chlorophyll protein CP47 in photosystem II.

PubMed

Gleiter, H M; Haag, E; Shen, J R; Eaton-Rye, J J; Inoue, Y; Vermaas, W F; Renger, G

1994-10-11

Several autotrophic mutant strains of Synechocystis sp. PCC 6803 carrying short deletions or a single-site mutation within the large, lumen-exposed loop (loop E) of the chlorophyll a-binding photosystem II core protein, CP47, are analyzed for their functional properties by measuring the flash-induced pattern of thermoluminescence, oxygen yield, and fluorescence quantum yield. A physiological and biochemical characterization of these mutant strains has been given in two previous reports [Eaton-Rye, J.J., & Vermaas, W.F.J. (1991) Plant Mol. Biol. 17, 1165-1177; Haag, E., Eaton-Rye, J.J., Renger, G., & Vermaas, S. F.J. (1993) Biochemistry 32, 4444-4454]. The results of the present study show that deletion of charged and conserved amino acids in a region roughly located between residues 370 and 390 decreases the binding affinity of the extrinsic PS II-O protein to photosystem II. Marked differences with PSII-O deletion mutants are observed with respect to Ca2+ requirement and the flash-induced pattern of oxygen evolution. Under conditions where a sufficient light activation is provided, the psbB mutants assayed in this study reveal normal S-state parameters and lifetimes. The results bear two basic implications: (i) the manganese involved in water oxidation can still be bound in a functionally normal or only slightly distorted manner, and (ii) the binding of the extrinsic PS II-O protein to photosystem II is impaired in mutants carrying a deletion in the domain between residues 370 and 390, but the presence of the PS II-O protein is still of functional relevance for the PS II complex, e.g., for maintenance of a high-affinity binding site for Ca2+ and/or involvement during the process of photoactivation.

Biological water-oxidizing complex: a nano-sized manganese-calcium oxide in a protein environment.

PubMed

Najafpour, Mohammad Mahdi; Moghaddam, Atefeh Nemati; Yang, Young Nam; Aro, Eva-Mari; Carpentier, Robert; Eaton-Rye, Julian J; Lee, Choon-Hwan; Allakhverdiev, Suleyman I

2012-10-01

The resolution of Photosystem II (PS II) crystals has been improved using isolated PS II from the thermophilic cyanobacterium Thermosynechococcus vulcanus. The new 1.9 Å resolution data have provided detailed information on the structure of the water-oxidizing complex (Umena et al. Nature 473: 55-61, 2011). The atomic level structure of the manganese-calcium cluster is important for understanding the mechanism of water oxidation and to design an efficient catalyst for water oxidation in artificial photosynthetic systems. Here, we have briefly reviewed our knowledge of the structure and function of the cluster.

Enteral leucine supplementation increases protein synthesis in skeletal and cardiac muscles and visceral tissues of neonatal pigs through mTORC1-dependent pathways

USDA-ARS?s Scientific Manuscript database

Leucine activates mammalian target of rapamycin (mTOR) to upregulate protein synthesis (PS). To examine enteral Leu effects on PS and signaling activation, 5-d-old piglets were fed for 24 h diets containing: (i) LP, (ii) LP+L, or (iii) HP. PS in skeletal muscles, heart, liver, pancreas, and jejunum...

Study of the Mn-binding sites in photosystem II using antibodies raised against lumenal regions of the D1 and D2 reaction center proteins

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

Dalmasso, Enrique Agustin

The experiments discussed in this thesis focus on identifying the protein segments or specific amino acids which provide ligands to the Mn cluster of photosystem II (PS II). This Mn cluster plays a central role in the oxygen-evolving complex (OEC) of PS II. The Mn cluster is thought to be bound by lumenal regions of the PS II reaction center proteins known as D1 and D2. First, several peptides were synthesized which correspond to specific lumenal segments of the D1 and D2 proteins. Next, polyclonal antibodies were successfully elicited using three of these peptides. The peptides recognized by these antibodiesmore » correspond to protein segments of the spinach reaction center proteins: Ile-321 to Ala-344 of D1 (D1-a), Asp-319 to Arg-334 of D1 (D1-b), and Val-300 to Asn-319 of D2 (D2-a). These antibodies were then used in assays which were developed to structurally or functionally probe the potential Mn-binding regions of the D1 and D2 proteins.« less

Immobilization of 5-aminopyridine-2-tetrazole on cross-linked polystyrene for the preparation of a new adsorbent to remove heavy metal ions from aqueous solution.

PubMed

Zhang, Yu; Chen, Youning; Wang, Chaozhan; Wei, Yinmao

2014-07-15

Novel 5-aminopyridine-2-tetrazole-functionalized polystyrene resin (APTZ-PS) was prepared by anchoring 5-aminopyridine-2-carbonitrile onto chloromethylated polystyrene beads (CMPS) and subsequently using the cyano-tetrazole conversion reaction. The APTZ-PS resin was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and specific surface area and pore size analyses. The adsorption experiments of the prepared resin for heavy metal ions were conducted by batch methods. The effects of the experimental conditions, such as pH, contact time and initial metal ion concentration on the adsorption properties of Cu(II), Pb(II) and Hg(II) were investigated. The results showed that the resin possessed perfect adsorption capacities for Cu(II), Pb(II) and Hg(II), and the selectivity was different from the commonly used iminodiacetic acid-chelating resin. The sorption kinetics of the three metal ions followed the pseudo-second-order equation. The adsorption isotherms for Cu(II) and Pb(II) could be better fitted by the Langmuir model than the Freundlich model, whereas the Freundlich model was the best for the Hg(II) ion. Even after five consecutive adsorption-desorption cycles, no obvious change in the adsorption capacity of the resin was found, which implied that the APTZ-PS resin was suitable for the efficient removal of heavy metal ions from aqueous solution. Copyright © 2014 Elsevier B.V. All rights reserved.

On the positronium spin conversion reactions caused by some macrocyclic Co II complexes

NASA Astrophysics Data System (ADS)

Fantola-Lazzarini, Anna L.; Lazzarini, Ennio

2002-08-01

The rate constants, kCR, of ortho- into para-positronium ( o-Ps→ p-Ps) spin conversion reactions, CR, caused by the high-spin [Co IIsep] 2+, [Co IIdinosar] 2+ and [Co IIdiamsar] 2+ macrocyclic complexes and also by high-spin [Co II sen] 2+ tripod complex were measured at several temperatures. The delocalizations, β, of Co II unpaired electrons, promoted by the mentioned ligands, were determined by using the previously established correlations between kCR and the electron delocalization β of unpaired metal electrons. β is given by the ratio between the Racah inter-electronic repulsion parameters of complexes, B, and that of the free ions, B0. The β values are compared with those of the Co II complexes with en (1,2-ethanediamine), pn (1,2 propanediamine) and dien (2,2' diamino diethylamine) ligands. The kCR rate constants are also compared with those of the Ps oxidation reactions, OR, promoted by the corresponding Co III complexes. It is concluded that, unlike OR's, the CR's do not occur by formation of hepta-coordinate adducts with Ps atoms.

[Response of photosynthetic characteristics of peanut seedlings leaves to low light].

PubMed

Zhang, Kun; Wan, Yong-shan; Liu, Feng-zhen; Zhang, Er-qun; Wang, Su

2009-12-01

To investigate the effects of shading and light recovery on the photosynthetic characteristics of peanut seedlings leaves, different shading treatments including no shading, 27% shading, 43% shading, and 77% shading were performed with black sunshade net at the seedling stage of two peanut cultivars Fenghua 1 and Fenghua 2, with related parameters determined. It was shown that with the increase of shading degree, the leaf chlorophyll content, actual PSII photochemical efficiency under irradiance (phi(PS II)), and maximum PS II photochemical efficiency (Fv/Fm) of test cultivars increased, while the Chl a/b ratio and photosynthetic rate (Pn) decreased. On the first day after light recovery, the Pn and stomatal conductance (Gs) decreased while the intercellular CO2 concentration (Ci) increased with increasing shading degree when measured under high light, but the Pn increased and the Gs and Ci decreased with increasing shading degree when measured under low light. The ratio of Pn measured under low light to that measured under high light increased significantly. With increasing shading degree, the light compensation point, light saturation point, CO2 compensation point, CO2 saturation point, and carboxylation efficiency decreased, while the apparent quantum yield increased. After the removal of shading, the Pn, phi(PS II), and Fv/Fm under natural light decreased immediately, but increased gradually 3-5 days after. 15 days after light recovery, the Pn, phi(PS II) and Fv/Fm in treatment 27% shading recovered to the level of no shading. As for the other treatments, the restored extent differed with shading degree and test variety. In the same treatments, the leaf chlorophyll content, Pn and phi(PS II) of Fenghua 1 were higher than those of Fenghua 2. The results demonstrated that shading at seedling stage improved the capabilities of test varieties in using low light, but reduced the capabilities in using high light.

A new insert sample approach to paper spray mass spectrometry: a paper substrate with paraffin barriers.

PubMed

Colletes, T C; Garcia, P T; Campanha, R B; Abdelnur, P V; Romão, W; Coltro, W K T; Vaz, B G

2016-03-07

The analytical performance for paper spray (PS) using a new insert sample approach based on paper with paraffin barriers (PS-PB) is presented. The paraffin barrier is made using a simple, fast and cheap method based on the stamping of paraffin onto a paper surface. Typical operation conditions of paper spray such as the solvent volume applied on the paper surface, and the paper substrate type are evaluated. A paper substrate with paraffin barriers shows better performance on analysis of a range of typical analytes when compared to the conventional PS-MS using normal paper (PS-NP) and PS-MS using paper with two rounded corners (PS-RC). PS-PB was applied to detect sugars and their inhibitors in sugarcane bagasse liquors from a second generation ethanol process. Moreover, the PS-PB proved to be excellent, showing results for the quantification of glucose in hydrolysis liquors with excellent linearity (R(2) = 0.99), limits of detection (2.77 mmol L(-1)) and quantification (9.27 mmol L(-1)). The results are better than for PS-NP and PS-RC. The PS-PB was also excellent in performance when compared with the HPLC-UV method for glucose quantification on hydrolysis of liquor samples.

Study on thermal, mechanical and adsorption properties of amine-functionalized MCM-41/PMMA and MCM-41/PS nanocomposites prepared by ultrasonic irradiation.

PubMed

Mohammadnezhad, Gholamhossein; Abad, Saeed; Soltani, Roozbeh; Dinari, Mohammad

2017-11-01

In this study, two common industrial polymers, poly(methyl methacrylate) (PMMA) and polystyrene (PS), were incorporated into amine-functionalized MCM-41 mesoporous silica as reinforcement agents via an ultrasonic assisted method as a facile, fast, eco-friendly, and versatile synthetic tool. Amino functionalization of MCM-41 were performed by 3-aminopropyl triethoxysilane as a coupling agent and it is denoted as APTS-MCM-41. The obtained nanocomposites (NCs), APTS-MCM-41/PMMA and APTS-MCM-41/PS, were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), and thermogravimetric analysis (TGA). Their mechanical properties were also probed via stress-strain curves and improved tensile properties were observed in the NCs relative to the neat polymers. Additionally, APTS-MCM-41/PMMA exhibited better mechanical properties than APTS-MCM-41/PS. Sorption studies were carried out on the two NCs and the effect of different process parameters, namely, pH, contact time, and initial Cd(II) concentration investigated in batch mode. Pseudo-second order and intraparticle diffusion models explain the Cd(II) kinetics more effectively for APTS-MCM-41/PMMA and APTS-MCM-41/PS, respectively. The adsorption isotherm data fitted well to Langmuir isotherm for both NCs and the maximum monolayer adsorption capacities were found to be 24.75mg/g and 10.42mg/g for APTS-MCM-41/PMMA and APTS-MCM-41/PS, respectively. The results demonstrate that the NCs show potential for use in adsorption of heavy metal ion such as Cd(II) from aqueous media. Copyright © 2017 Elsevier B.V. All rights reserved.

Particle size analysis of lamb meat: Effect of homogenization speed, comparison with myofibrillar fragmentation index and its relationship with shear force.

PubMed

Karumendu, L U; Ven, R van de; Kerr, M J; Lanza, M; Hopkins, D L

2009-08-01

The impact of homogenization speed on Particle Size (PS) results was examined using samples from the M.longissimus thoracis et lumborum (LL) of 40 lambs. One gram duplicate samples from meat aged for 1 and 5days were homogenized at five different speeds; 11,000, 13,000, 16,000, 19,000 and 22,000rpm. In addition to this LL samples from 30 different lamb carcases also aged for 1 and 5days were used to study the comparison between PS and myofibrillar fragmentation index (MFI) values. In this case, 1g duplicate samples (n=30) were homogenized at 16,000rpm and the other half (0.5g samples) at 11,000rpm (n=30). The homogenates were then subjected to respective combinations of treatments which included either PS analysis or the determination of MFI, both with or without three cycles of centrifugation. All 140 samples of LL included 65g blocks for subsequent shear force (SF) testing. Homogenization at 16,000rpm provided the greatest ability to detect ageing differences for particle size between samples aged for 1 and 5days. Particle size at the 25% quantile provided the best result for detecting differences due to ageing. It was observed that as ageing increased the mean PS decreased and was significantly (P<0.001) less for 5days aged samples compared to 1day aged samples, while MFI values significantly increased (P<0.001) as ageing period increased. When comparing the PS and MFI methods it became apparent that, as opposed to the MFI method, there was a greater coefficient of variation for the PS method which warranted a quality assurance system. Given this requirement and examination of the mean, standard deviation and the 25% quantile for PS data it was concluded that three cycles of centrifugation were not necessary and this also applied to the MFI method. There were significant correlations (P<0.001) within the same lamb loin sample aged for a given period between mean MFI and mean PS (-0.53), mean MFI and mean SF (-0.38) and mean PS and mean SF (0.23). It was concluded that PS analysis offers significant potential for streamlining determination of myofibrillar degradation when samples are measured after homogenization at 16,000rpm with no centrifugation.

Near-infrared image-guided laser ablation of artificial caries lesions

NASA Astrophysics Data System (ADS)

Tao, You-Chen; Fan, Kenneth; Fried, Daniel

2007-02-01

Laser removal of dental hard tissue can be combined with optical, spectral or acoustic feedback systems to selectively ablate dental caries and restorative materials. Near-infrared (NIR) imaging has considerable potential for the optical discrimination of sound and demineralized tissue. The objective of this study was to test the hypothesis that two-dimensional NIR images of demineralized tooth surfaces can be used to guide CO II laser ablation for the selective removal of artificial caries lesions. Highly patterned artificial lesions were produced by submerging 5 x 5 mm2 bovine enamel samples in demineralized solution for a 9-day period while sound areas were protected with acid resistant varnish. NIR imaging and polarization sensitive optical coherence tomography (PS-OCT) were used to acquire depth-resolved images at a wavelength of 1310-nm. An imaging processing module was developed to analyze the NIR images and to generate optical maps. The optical maps were used to control a CO II laser for the selective removal of the lesions at a uniform depth. This experiment showed that the patterned artificial lesions were removed selectively using the optical maps with minimal damage to sound enamel areas. Post-ablation NIR and PS-OCT imaging confirmed that demineralized areas were removed while sound enamel was conserved. This study successfully demonstrated that near-IR imaging can be integrated with a CO II laser ablation system for the selective removal of dental caries.

Angiotensin II, hypertension and angiotensin II receptor antagonism: Roles in the behavioural and brain pathology of a mouse model of Alzheimer's disease.

PubMed

Wiesmann, Maximilian; Roelofs, Monica; van der Lugt, Robert; Heerschap, Arend; Kiliaan, Amanda J; Claassen, Jurgen Ahr

2017-07-01

Elevated angiotensin II causes hypertension and contributes to Alzheimer's disease by affecting cerebral blood flow. Angiotensin II receptor blockers may provide candidates to reduce (vascular) risk factors for Alzheimer's disease. We studied effects of two months of angiotensin II-induced hypertension on systolic blood pressure, and treatment with the angiotensin II receptor blockers, eprosartan mesylate, after one month of induced hypertension in wild-type C57bl/6j and AβPPswe/PS1ΔE9 (AβPP/PS1/Alzheimer's disease) mice. AβPP/PS1 showed higher systolic blood pressure than wild-type. Subsequent eprosartan mesylate treatment restored this elevated systolic blood pressure in all mice. Functional connectivity was decreased in angiotensin II-infused Alzheimer's disease and wild-type mice, and only 12 months of Alzheimer's disease mice showed impaired cerebral blood flow. Only angiotensin II-infused Alzheimer's disease mice exhibited decreased spatial learning in the Morris water maze. Altogether, angiotensin II-induced hypertension not only exacerbated Alzheimer's disease-like pathological changes such as impairment of cerebral blood flow, functional connectivity, and cognition only in Alzheimer's disease model mice, but it also induced decreased functional connectivity in wild-type mice. However, we could not detect hypertension-induced overexpression of Aβ nor increased neuroinflammation. Our findings suggest a link between midlife hypertension, decreased cerebral hemodynamics and connectivity in an Alzheimer's disease mouse model. Eprosartan mesylate treatment restored and beneficially affected cerebral blood flow and connectivity. This model could be used to investigate prevention/treatment strategies in early Alzheimer's disease.

Cartilage collagen type II seromarker patterns in axial spondyloarthritis and psoriatic arthritis: associations with disease activity, smoking and HLA-B27.

PubMed

Munk, Heidi Lausten; Gudmann, Natasja Staehr; Christensen, Anne Friesgaard; Ejstrup, Leif; Sorensen, Grith Lykke; Loft, Anne Gitte; Bay-Jensen, Anne C; Siebuhr, Anne Sofie; Junker, Peter

2016-04-01

The aim of the study was to assess the possible association between type II collagen turnover seromarkers and disease profile in patients with axial spondyloarthritis (SpA) and psoriatic arthritis (PsA). Outpatients with axial SpA (n = 110) or PsA (n = 101) underwent clinical examination including disease activity measures and HLA-B27 typing. The procollagen IIA N-terminal peptide (PIIANP) and a matrix metalloproteinase-generated type II collagen fragment (C2M) were quantified in serum by ELISA. C2M was higher in SpA than in controls, 0.41 versus 0.36 ng/ml (p = 0.004), while PIIANP did not differ between patients and healthy subjects, 2252 versus 2142 ng/ml (p = 0.13). However, DMARD-naïve SpA patients had higher PIIANP, 2461 ng/ml (p = 0.01) and C2M, 0.44 ng/ml (p = 0.0007) levels than controls, and PIIANP correlated with CRP (ρ = 0.34). C2M was lower in SpA smokers, 0.36 ng/ml versus non-smokers, 0.43 ng/ml (p = 0.02), while PIIANP was higher in HLA-B27 positive, 2312 ng/ml versus negative patients, 2021 ng/ml (p = 0.03). In PsA, PIIANP and C2M did not differ between patients and controls, but PIIANP was elevated in patients not receiving DMARDs, 2726 ng/ml. In PsA, PIIANP and C2M did not differ according to smoking and HLA-B27. Cartilage degradation assessed by C2M is increased in SpA irrespective of treatment but not in PsA. Cartilage synthesis reflected by PIIANP is increased in untreated SpA and PsA. PIIANP correlates with CRP in SpA while not in PsA. In DMARD-naïve SpA but not in PsA, HLA-B27 positivity and smoking are associated with a chondro-proliferative metabolic pattern.

Electroporation of the photosynthetic membrane: structural changes in protein and lipid-protein domains.

PubMed Central

Rosemberg, Y; Rotenberg, M; Korenstein, R

1994-01-01

A biological membrane undergoes a reversible permeability increase through structural changes in the lipid domain when exposed to high external electric fields. The present study shows the occurrence of electric field-induced changes in the conductance of the proton channel of the H(+)-ATPase as well as electric field-induced structural changes in the lipid-protein domain of photosystem (PS) II in the photosynthetic membrane. The study was carried out by analyzing the electric field-stimulated delayed luminescence (EPL), which originates from charge recombination in the protein complexes of PS I and II of photosynthetic vesicles. We established that a small fraction of the total electric field-induced conductance change was abolished by N,N'-dicyclohexylcarbodiimide (DCCD), an inhibitor of the H(+)-ATPase. This reversible electric field-induced conductance change has characteristics of a small channel and possesses a lifetime < or = 1 ms. To detect electric field-induced changes in the lipid-protein domains of PS II, we examined the effects of phospholipase A2 (PLA2) on EPL. Higher values of EPL were observed from vesicles that were exposed in the presence of PLA2 to an electroporating electric field than to a nonelectroporating electric field. The effect of the electroporating field was a long-lived one, lasting for a period > or = 2 min. This effect was attributed to long-lived electric field-induced structural changes in the lipid-protein domains of PS II. PMID:7811916

Recovery of photosynthesis in 1-year-old needles of unfertilized and fertilized Norway spruce (Picea abies (L.) Karst.) during spring.

PubMed

Strand, M; Lundmark, T

1995-03-01

Photosynthetic O(2) evolution and chlorophyll a fluorescence were measured in 1-year-old needles of unfertilized and fertilized trees of Norway spruce (Picea abies (L.) Karst.) during recovery of photosynthesis from winter inhibition in northern Sweden. Measurements were made under laboratory conditions at 20 degrees C. In general, the CO(2)-saturated rate of O(2) evolution was higher in needles of fertilized trees than in needles of unfertilized trees over a wide range of incident photon flux densities. Furthermore, the maximum photochemical efficiency of photosystem (PS) II, as indicated by the ratio of variable to maximum fluorescence (F(V)/F(M)) was higher in needles of fertilized trees than in needles of unfertilized trees. The largest differences in F(V)/F(M) between the two treatments occurred before the main recovery of photosynthesis from winter inhibition in late May. The rate of O(2) evolution was higher in needles of north-facing branches than in needles of south-facing branches in the middle of May. Simultaneous measurements of O(2) exchange and chlorophyll fluorescence indicated that differences in the rate of O(2) evolution between the two treatments were paralleled by differences in the rate of PS II electron transport determined by chlorophyll fluorescence. We suggest that, during recovery of photosynthesis from winter inhibition, the balance between carbon assimilation and PS II electron transport was maintained largely by adjustments in the nonphotochemical dissipation of excitation energy within PS II.

Fine tuning the energetics of excited-state intramolecular proton transfer (ESIPT): white light generation in a single ESIPT system.

PubMed

Tang, Kuo-Chun; Chang, Ming-Jen; Lin, Tsung-Yi; Pan, Hsiao-An; Fang, Tzu-Chien; Chen, Kew-Yu; Hung, Wen-Yi; Hsu, Yu-Hsiang; Chou, Pi-Tai

2011-11-09

Using 7-hydroxy-1-indanone as a prototype (I), which exhibits excited-state intramolecular proton transfer (ESIPT), chemical modification has been performed at C(2)-C(3) positions by fusing benzene (molecule II) and naphthalene rings, (molecule III). I undergoes an ultrafast rate of ESIPT, resulting in a unique tautomer emission (λ(max) ∼530 nm), whereas excited-state equilibrium is established for both II and III, as supported by the dual emission and the associated relaxation dynamics. The forward ESIPT (normal to proton-transfer tautomer species) rates for II and III are deduced to be (30 ps)(-1) and (22 ps)(-1), respectively, while the backward ESIPT rates are (11 ps)(-1) and (48 ps)(-1). The ESIPT equilibrium constants are thus calculated to be 0.37 and 2.2 for II and III, respectively, giving a corresponding free energy change of 0.59 and -0.47 kcal/mol between normal and tautomer species. For III, normal and tautomer emissions in solid are maximized at 435 and 580 nm, respectively, achieving a white light generation with Commission Internationale de l'Eclairage (CIE) (0.30, 0.27). An organic light-emitting diode based on III is also successfully fabricated with maximum brightness of 665 cd m(-2) at 20 V (885 mA cm(-2)) and the CIE coordinates of (0.26, 0.35). The results provide the proof of concept that the white light generation can be achieved in a single ESIPT system.

Enzyme-linked immunosorbent assay for detection of pertussis immunoglobulin A in nasopharyngeal secretions as an indicator of recent infection.

PubMed Central

Goodman, Y E; Wort, A J; Jackson, F L

1981-01-01

An enzyme-linked immunosorbent assay was developed for detection of immunoglobulin A (IgA) antibody to Bordetella pertussis (PsIgA) in nasopharyngeal secretions as an indicator of recent infection. Secretion specimens submitted for pertussis culture were examined for PsIgA by this technique. Of 348 specimens tested, B. pertussis was cultured from 57, and PsIgA was detected in 8 culture-positive and 40 culture-negative specimens. The average time between onset of symptoms and specimen collection for the culture-positive, PsIgA-negative specimens was 10 days; for the culture-positive, PsIgA-positive specimens, 15 days; and for the culture-negative, PsIgA-positive specimens, 36 days. Examination of paired samples available from several culture-proven cases demonstrated conversion from a negative PsIgA in the early sample to a positive PsIgA in the follow-up sample. Our results indicate that PsIgA is produced during natural human infection and does not arise as a result of parenteral vaccination. PsIgA usually appears in the nasopharyngeal secretions during the second or third week of illness and persists for at least 3 months. The detection of PsIgA in secretions may be a valuable diagnostic aid in culture-negative patients with pertussis. Images PMID:6259201

The water-water cycle as alternative photon and electron sinks.

PubMed

Asada, K

2000-10-29

The water-water cycle in chloroplasts is the photoreduction of dioxygen to water in photosystem I (PS I) by the electrons generated in photosystem II (PS II) from water. In the water-water cycle, the rate of photoreduction of dioxygen in PS I is several orders of magnitude lower than those of the disproportionation of superoxide catalysed by superoxide dismutase, the reduction of hydrogen peroxide to water catalysed by ascorbate peroxidase, and the reduction of the resulting oxidized forms of ascorbate by reduced ferredoxin or catalysed by either dehydroascorbate reductase or monodehydroascorbate reductase. The water-water cycle therefore effectively shortens the lifetimes of photoproduced superoxide and hydrogen peroxide to suppress the production of hydroxyl radicals, their interactions with the target molecules in chloroplasts, and resulting photoinhibition. When leaves are exposed to photon intensities of sunlight in excess of that required to support the fixation of CO2, the intersystem electron carriers are over-reduced, resulting in photoinhibition. Under such conditions, the water-water cycle not only scavenges active oxygens, but also safely dissipates excess photon energy and electrons, in addition to downregulation of PS II and photorespiration. The dual functions of the water-water cycle for protection from photoinhibition under photon excess stress are discussed, along with its functional evolution.

A Measurement of the Charged and Neutral B Meson Lifetimes Using Fully Reconstructed Decays

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

Barrera, Barbara

Data collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC are used to study the lifetimes of the B{sup 0} and B{sup +} mesons. The data sample consists of 7.4 fb{sup -1} collected near the {Upsilon}(4S) resonance. B{sup 0} and B{sup +} mesons are fully reconstructed in several exclusive hadronic decay modes to charm and charmonium final states. The B lifetimes are determined from the flight length difference between the two B mesons which are pair-produced in the {Upsilon}(4S) decay. The preliminary measurements of the lifetimes are {tau}B{sup 0} = 1.506 {+-} 0.052 (stat) {+-} 0.029more » (syst) ps, {tau}B{sup +} = 1.602 {+-} 0.049 (stat) {+-} 0.035 (syst) ps, and of their ratio is {tau}B{sup +}/{tau}B{sup 0} = 1.065 {+-} 0.044 (stat) {+-} 0.021 (syst).« less

A Measurement of the Charged and Neutral B Meson Lifetimes Using Fully Reconstructed Decays

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

Barrera, Barbara

Data collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC are used to study the lifetimes of the B{sup 0} and B{sup +} mesons. The data sample consists of 7.4 fb{sup {minus}1} collected near the Upsilon(4S) resonance. B{sup 0} and B{sup +} mesons are fully reconstructed in several exclusive hadronic decay modes to charm and charmonium final states. The B lifetimes are determined from the flight length difference between the two B mesons which are pair-produced in the Upsilon(4S) decay. The preliminary measurements of the lifetimes are tau{sub B0} = 1.506 {+-} 0.052 (stat) {+-} 0.029more » (syst) ps, tau{sub B+} = 1.602 {+-} 0.049 (stat) {+-} 0.035 (syst) ps, and of their ratio is tau{sub B+}/tau{sub B0} = 1.065 {+-} 0.044 (stat) {+-} 0.021 (syst).« less

An EPR study of the pH dependence of formate effects on Photosystem II.

PubMed

Jajoo, Anjana; Katsuta, Nobuhiro; Kawamori, Asako

2006-04-01

Effects of formate on rates of O(2) evolution and electron paramagnetic resonance (EPR) signals were observed in the oxygen evolving PS II membranes as a function of pH. In formate treated PS II membranes, decrease in pH value resulted in the inhibition of the O(2) evolving activity, a decrease in the intensity of S(2) state multiline signal but an increase in the intensity of the Q(A)(-)Fe(2+) EPR signal. Time-resolved EPR study of the Y(Z)(*) decay kinetics showed that the light-induced intensity of Y(Z)(*) EPR signal was proportional to the formate concentration. The change in the pH affected both the light-induced intensities and the decay rates of Y(Z)(*), which was found to be faster at lower pH. At 253 K, t(1/e) value of Y(Z)(*) decay kinetics was found to be 8-10 s at pH 6.0 and 18-21 s at pH 5.0. The results presented here indicate that the extent of inhibition at the donor and the acceptor side of PS II due to formate is pH dependent, being more effective at lower pH.

Effects of marine actinomycete on the removal of a toxicity alga Phaeocystis globose in eutrophication waters.

PubMed

Zhang, Huajun; Zhang, Su; Peng, Yun; Li, Yi; Chen, Zhangran; Xu, Hong; Yu, Zhiming; Zheng, Wei; Zheng, Tianling

2015-01-01

Phaeocystis globosa blooms in eutrophication waters can cause severely damage in marine ecosystem and consequently influence human activities. This study investigated the effect and role of an algicidal actinomycete (Streptomyces sp. JS01) on the elimination process of P. globosa. JS01 supernatant could alter algal cell membrane permeability in 4 h when analyzed with flow cytometry. Reactive oxygen species (ROS) levels were 7.2 times higher than that at 0 h following exposure to JS01 supernatant for 8 h, which indicated that algal cells suffered from oxidative damage. The Fv/Fm value which could reflect photosystem II (PS II) electron flow status also decreased. Real-time PCR showed that the expression of the photosynthesis related genes psbA and rbcS were suppressed by JS01 supernatant, which might induce damage to PS II. Our results demonstrated that JS01 supernatant can change algal membrane permeability in a short time and then affect photosynthesis process, which might block the PS II electron transport chain to produce excessive ROS. This experiment demonstrated that Streptomyces sp. JS01 could eliminate harmful algae in marine waters efficiently and may be function as a harmful algal bloom controller material.

Effects of marine actinomycete on the removal of a toxicity alga Phaeocystis globose in eutrophication waters

PubMed Central

Zhang, Huajun; Zhang, Su; Peng, Yun; Li, Yi; Chen, Zhangran; Xu, Hong; Yu, Zhiming; Zheng, Wei; Zheng, Tianling

2015-01-01

Phaeocystis globosa blooms in eutrophication waters can cause severely damage in marine ecosystem and consequently influence human activities. This study investigated the effect and role of an algicidal actinomycete (Streptomyces sp. JS01) on the elimination process of P. globosa. JS01 supernatant could alter algal cell membrane permeability in 4 h when analyzed with flow cytometry. Reactive oxygen species (ROS) levels were 7.2 times higher than that at 0 h following exposure to JS01 supernatant for 8 h, which indicated that algal cells suffered from oxidative damage. The Fv/Fm value which could reflect photosystem II (PS II) electron flow status also decreased. Real-time PCR showed that the expression of the photosynthesis related genes psbA and rbcS were suppressed by JS01 supernatant, which might induce damage to PS II. Our results demonstrated that JS01 supernatant can change algal membrane permeability in a short time and then affect photosynthesis process, which might block the PS II electron transport chain to produce excessive ROS. This experiment demonstrated that Streptomyces sp. JS01 could eliminate harmful algae in marine waters efficiently and may be function as a harmful algal bloom controller material. PMID:26042109

Mechanism of action of anions on the electron transport chain in thylakoid membranes of higher plants.

PubMed

Singh-Rawal, Pooja; Zsiros, Ottó; Bharti, Sudhakar; Garab, Gyozo; Jajoo, Anjana

2011-04-01

With an aim to improve our understanding of the mechanisms behind specific anion effects in biological membranes, we have studied the effects of sodium salts of anions of varying valency in thylakoid membranes. Rates of electron transport of PS II and PS I, 77K fluorescence emission and excitation spectra, cyclic electron flow around PS I and circular dichroism (CD) spectra were measured in thylakoid membranes in order to elucidate a general mechanism of action of inorganic anions on photosynthetic electron transport chain. Re-distribution of absorbed excitation energy has been observed as a signature effect of inorganic anions. In the presence of anions, such as nitrite, sulphate and phosphate, distribution of absorbed excitation energy was found to be more in favor of Photosystem I (PS I). The amount of energy distributed towards PS I depended on the valency of the anion. In this paper, we propose for the first time that energy re-distribution and its valence dependence may not be the effect of anions per se. The entry of negative charge (anion) is accompanied by influx of positive charge (protons) to maintain a balance of charge across the thylakoid membranes. As reflected by the CD spectra, the observed energy re-distribution could be a result of structural rearrangements of the protein complexes of PS II caused by changes in the ionic environment of the thylakoid lumen.

Molecular features of colorectal polyps presenting Kudo’s type II mucosal crypt pattern: are they based on the same mechanism of tumorigenesis?

PubMed Central

Shinmura, Kensuke; Konishi, Kazuo; Yamochi, Toshiko; Kubota, Yutaro; Yano, Yuichiro; Katagiri, Atsushi; Muramoto, Takashi; Kihara, Toshihiro; Tojo, Masayuki; Konda, Kenichi; Tagawa, Teppei; Yanagisawa, Fumito; Kogo, Mari; Makino, Reiko; Takimoto, Masafumi; Yoshida, Hitoshi

2014-01-01

Background and study aims: The molecular features of serrated polyps (SPs) with hyperplastic crypt pattern, also called Kudo’s type II observed by chromoendoscopy, were evaluated. Methods: The clinicopathological and molecular features of 114 SPs with a hyperplastic pit pattern detected under chromoendoscopy (five dysplastic SPs, 63 sessile serrated adenoma/polyps (SSA/Ps), 36 microvesicular hyperplastic polyps (MVHPs), and 10 goblet cell-rich hyperplastic polyps (GCHPs)) were examined. The frequency of KRAS and BRAF mutations and CpG island methylator phenotype (CIMP) were investigated. Results: Dysplastic SPs and SSA/Ps were frequently located in the proximal colon compared to others (SSA/Ps vs. MVHPs or GCHPs, P < 0.0001). No significant difference was found in the frequency of BRAF mutation among SPs apart from GCHP (60 % for dysplastic SPs, 44 % for SSA/Ps, 47 % for MVHPs, and 0 % for GCHPs). The frequency of CIMP was higher in dysplastic SPs or SSA/Ps than in MVHPs or GCHPs (60 % for dysplastic SPs, 56 % for SSA/Ps, 32 % for MVHPs, and 10 % for GCHPs) (SSA/Ps vs. GCHP, P = 0.0068). When serrated neoplasias (SNs) and MVHPs were classified into proximal and distal lesions, the frequency of CIMP was significantly higher in the proximal compared to the distal SNs (64 % vs. 11 %, P = 0.0032). Finally, multivariate analysis showed that proximal location and BRAF mutation were significantly associated with an increased risk of CIMP. Conclusions: Distinct molecular features were observed between proximal and distal SPs with hyperplastic crypt pattern. Proximal MVHPs may develop more frequently through SSA/Ps to CIMP cancers than distal MVHPs. PMID:26134964

Molecular features of colorectal polyps presenting Kudo's type II mucosal crypt pattern: are they based on the same mechanism of tumorigenesis?

PubMed

Shinmura, Kensuke; Konishi, Kazuo; Yamochi, Toshiko; Kubota, Yutaro; Yano, Yuichiro; Katagiri, Atsushi; Muramoto, Takashi; Kihara, Toshihiro; Tojo, Masayuki; Konda, Kenichi; Tagawa, Teppei; Yanagisawa, Fumito; Kogo, Mari; Makino, Reiko; Takimoto, Masafumi; Yoshida, Hitoshi

2014-09-01

The molecular features of serrated polyps (SPs) with hyperplastic crypt pattern, also called Kudo's type II observed by chromoendoscopy, were evaluated. The clinicopathological and molecular features of 114 SPs with a hyperplastic pit pattern detected under chromoendoscopy (five dysplastic SPs, 63 sessile serrated adenoma/polyps (SSA/Ps), 36 microvesicular hyperplastic polyps (MVHPs), and 10 goblet cell-rich hyperplastic polyps (GCHPs)) were examined. The frequency of KRAS and BRAF mutations and CpG island methylator phenotype (CIMP) were investigated. Dysplastic SPs and SSA/Ps were frequently located in the proximal colon compared to others (SSA/Ps vs. MVHPs or GCHPs, P < 0.0001). No significant difference was found in the frequency of BRAF mutation among SPs apart from GCHP (60 % for dysplastic SPs, 44 % for SSA/Ps, 47 % for MVHPs, and 0 % for GCHPs). The frequency of CIMP was higher in dysplastic SPs or SSA/Ps than in MVHPs or GCHPs (60 % for dysplastic SPs, 56 % for SSA/Ps, 32 % for MVHPs, and 10 % for GCHPs) (SSA/Ps vs. GCHP, P = 0.0068). When serrated neoplasias (SNs) and MVHPs were classified into proximal and distal lesions, the frequency of CIMP was significantly higher in the proximal compared to the distal SNs (64 % vs. 11 %, P = 0.0032). Finally, multivariate analysis showed that proximal location and BRAF mutation were significantly associated with an increased risk of CIMP. Distinct molecular features were observed between proximal and distal SPs with hyperplastic crypt pattern. Proximal MVHPs may develop more frequently through SSA/Ps to CIMP cancers than distal MVHPs.

Comparing the utility of DSM-5 Section II and III antisocial personality disorder diagnostic approaches for capturing psychopathic traits.

PubMed

Few, Lauren R; Lynam, Donald R; Maples, Jessica L; MacKillop, James; Miller, Joshua D

2015-01-01

The current study compares the 2 diagnostic approaches (Section II vs. Section III) included in the Diagnostic and Statistical Manual for Mental Disorders-5 (DSM-5; American Psychiatric Association, 2013) for diagnosis of antisocial personality disorder (ASPD) in terms of their relations with psychopathic traits and externalizing behaviors (EBs). The Section III approach to ASPD, which is more explicitly trait-based than the Section II approach, also includes a psychopathy specifier (PS) that was created with the goal of making the diagnosis of ASPD more congruent with psychopathy. In a community sample of individuals currently receiving mental health treatment (N = 106), ratings of the 2 DSM-5 diagnostic approaches were compared in relation to measures of psychopathy, as well as indices of EBs. Both DSM-5 ASPD approaches were significantly related to the psychopathy scores, although the Section III approach accounted for almost twice the amount of variance when compared with the Section II approach. Relatively little of this predictive advantage, however, was due to the PS, as these traits manifested little evidence of incremental validity in relation to existing psychopathy measures and EBs, with the exception of a measure of fearless dominance. Overall, the DSM-5 Section III diagnostic approach for ASPD is more convergent with the construct of psychopathy, from which ASPD was originally derived. These improvements, however, are due primarily to the new trait-based focus in the Section III ASPD diagnosis rather than the assessment of personality dysfunction or the inclusion of additional "psychopathy-specific" traits. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Effect of molecular characteristics on cellular uptake, subcellular localization, and phototoxicity of Zn(II) N-alkylpyridylporphyrins.

PubMed

Ezzeddine, Rima; Al-Banaw, Anwar; Tovmasyan, Artak; Craik, James D; Batinic-Haberle, Ines; Benov, Ludmil T

2013-12-20

Tetra-cationic Zn(II) meso-tetrakis(N-alkylpyridinium-2 (or -3 or -4)-yl)porphyrins (ZnPs) with progressively increased lipophilicity were synthesized to investigate how the tri-dimensional shape and lipophilicity of the photosensitizer (PS) affect cellular uptake, subcellular distribution, and photodynamic efficacy. The effect of the tri-dimensional shape of the molecule was studied by shifting the N-alkyl substituent attached to the pyridyl nitrogen from ortho to meta and para positions. Progressive increase of lipophilicity from shorter hydrophilic (methyl) to longer amphiphilic (hexyl) alkyl chains increased the phototoxicity of the ZnP PSs. PS efficacy was also increased for all derivatives when the alkyl substituents were shifted from ortho to meta, and from meta to para positions. Both cellular uptake and subcellular distribution of the PSs were affected by the lipophilicity and the position of the alkyl chains on the periphery of the porphyrin ring. Whereas the hydrophilic ZnPs demonstrated mostly lysosomal distribution, the amphiphilic hexyl derivatives were associated with mitochondria, endoplasmic reticulum, and plasma membrane. A comparison of hexyl isomers revealed that cellular uptake and partition into membranes followed the order para > meta > ortho. Varying the position and length of the alkyl substituents affects (i) the exposure of cationic charges for electrostatic interactions with anionic biomolecules and (ii) the lipophilicity of the molecule. The charge, lipophilicity, and the tri-dimensional shape of the PS are the major factors that determine cellular uptake, subcellular distribution, and as a consequence, the phototoxicity of the PSs.

Effect of Molecular Characteristics on Cellular Uptake, Subcellular Localization, and Phototoxicity of Zn(II) N-Alkylpyridylporphyrins*

PubMed Central

Ezzeddine, Rima; Al-Banaw, Anwar; Tovmasyan, Artak; Craik, James D.; Batinic-Haberle, Ines; Benov, Ludmil T.

2013-01-01

Tetra-cationic Zn(II) meso-tetrakis(N-alkylpyridinium-2 (or -3 or -4)-yl)porphyrins (ZnPs) with progressively increased lipophilicity were synthesized to investigate how the tri-dimensional shape and lipophilicity of the photosensitizer (PS) affect cellular uptake, subcellular distribution, and photodynamic efficacy. The effect of the tri-dimensional shape of the molecule was studied by shifting the N-alkyl substituent attached to the pyridyl nitrogen from ortho to meta and para positions. Progressive increase of lipophilicity from shorter hydrophilic (methyl) to longer amphiphilic (hexyl) alkyl chains increased the phototoxicity of the ZnP PSs. PS efficacy was also increased for all derivatives when the alkyl substituents were shifted from ortho to meta, and from meta to para positions. Both cellular uptake and subcellular distribution of the PSs were affected by the lipophilicity and the position of the alkyl chains on the periphery of the porphyrin ring. Whereas the hydrophilic ZnPs demonstrated mostly lysosomal distribution, the amphiphilic hexyl derivatives were associated with mitochondria, endoplasmic reticulum, and plasma membrane. A comparison of hexyl isomers revealed that cellular uptake and partition into membranes followed the order para > meta > ortho. Varying the position and length of the alkyl substituents affects (i) the exposure of cationic charges for electrostatic interactions with anionic biomolecules and (ii) the lipophilicity of the molecule. The charge, lipophilicity, and the tri-dimensional shape of the PS are the major factors that determine cellular uptake, subcellular distribution, and as a consequence, the phototoxicity of the PSs. PMID:24214973

Administration of Bifidobacterium breve PS12929 and Lactobacillus salivarius PS12934, two strains isolated from human milk, to very low and extremely low birth weight preterm infants: a pilot study.

PubMed

Moles, Laura; Escribano, Esperanza; de Andrés, Javier; Montes, María Teresa; Rodríguez, Juan M; Jiménez, Esther; Sáenz de Pipaón, Miguel; Espinosa-Martos, Irene

2015-01-01

The preterm infant gut has been described as immature and colonized by an aberrant microbiota. Therefore, the use of probiotics is an attractive practice in hospitals to try to reduce morbidity and mortality in this population. The objective of this pilot study was to elucidate if administration of two probiotic strains isolated from human milk to preterm infants led to their presence in feces. In addition, the evolution of a wide spectrum of immunological compounds, including the inflammatory biomarker calprotectin, in both blood and fecal samples was also assessed. For this purpose, five preterm infants received two daily doses (~10(9) CFU) of a 1:1 mixture of Bifidobacterium breve PS12929 and Lactobacillus salivarius PS12934. Bacterial growth was detected by culture-dependent techniques in all the fecal samples. The phylum Firmicutes dominated in nearly all fecal samples while L. salivarius PS12934 was detected in all the infants at numerous sample collection points and B. breve PS12929 appeared in five fecal samples. Finally, a noticeable decrease in the fecal calprotectin levels was observed along time.

Structure of photosystem II and substrate binding at room temperature.

PubMed

Young, Iris D; Ibrahim, Mohamed; Chatterjee, Ruchira; Gul, Sheraz; Fuller, Franklin; Koroidov, Sergey; Brewster, Aaron S; Tran, Rosalie; Alonso-Mori, Roberto; Kroll, Thomas; Michels-Clark, Tara; Laksmono, Hartawan; Sierra, Raymond G; Stan, Claudiu A; Hussein, Rana; Zhang, Miao; Douthit, Lacey; Kubin, Markus; de Lichtenberg, Casper; Long Vo, Pham; Nilsson, Håkan; Cheah, Mun Hon; Shevela, Dmitriy; Saracini, Claudio; Bean, Mackenzie A; Seuffert, Ina; Sokaras, Dimosthenis; Weng, Tsu-Chien; Pastor, Ernest; Weninger, Clemens; Fransson, Thomas; Lassalle, Louise; Bräuer, Philipp; Aller, Pierre; Docker, Peter T; Andi, Babak; Orville, Allen M; Glownia, James M; Nelson, Silke; Sikorski, Marcin; Zhu, Diling; Hunter, Mark S; Lane, Thomas J; Aquila, Andy; Koglin, Jason E; Robinson, Joseph; Liang, Mengning; Boutet, Sébastien; Lyubimov, Artem Y; Uervirojnangkoorn, Monarin; Moriarty, Nigel W; Liebschner, Dorothee; Afonine, Pavel V; Waterman, David G; Evans, Gwyndaf; Wernet, Philippe; Dobbek, Holger; Weis, William I; Brunger, Axel T; Zwart, Petrus H; Adams, Paul D; Zouni, Athina; Messinger, Johannes; Bergmann, Uwe; Sauter, Nicholas K; Kern, Jan; Yachandra, Vittal K; Yano, Junko

2016-12-15

Light-induced oxidation of water by photosystem II (PS II) in plants, algae and cyanobacteria has generated most of the dioxygen in the atmosphere. PS II, a membrane-bound multi-subunit pigment protein complex, couples the one-electron photochemistry at the reaction centre with the four-electron redox chemistry of water oxidation at the Mn 4 CaO 5 cluster in the oxygen-evolving complex (OEC). Under illumination, the OEC cycles through five intermediate S-states (S 0 to S 4 ), in which S 1 is the dark-stable state and S 3 is the last semi-stable state before O-O bond formation and O 2 evolution. A detailed understanding of the O-O bond formation mechanism remains a challenge, and will require elucidation of both the structures of the OEC in the different S-states and the binding of the two substrate waters to the catalytic site. Here we report the use of femtosecond pulses from an X-ray free electron laser (XFEL) to obtain damage-free, room temperature structures of dark-adapted (S 1 ), two-flash illuminated (2F; S 3 -enriched), and ammonia-bound two-flash illuminated (2F-NH 3 ; S 3 -enriched) PS II. Although the recent 1.95 Å resolution structure of PS II at cryogenic temperature using an XFEL provided a damage-free view of the S 1 state, measurements at room temperature are required to study the structural landscape of proteins under functional conditions, and also for in situ advancement of the S-states. To investigate the water-binding site(s), ammonia, a water analogue, has been used as a marker, as it binds to the Mn 4 CaO 5 cluster in the S 2 and S 3 states. Since the ammonia-bound OEC is active, the ammonia-binding Mn site is not a substrate water site. This approach, together with a comparison of the native dark and 2F states, is used to discriminate between proposed O-O bond formation mechanisms.

Loss of Functional Photosystem II Reaction Centres in Zooxanthellae of Corals Exposed to Bleaching Conditions: Using Fluorescence Rise Kinetics.

PubMed

Hill, R; Larkum, A W D; Frankart, C; Kühl, M; Ralph, P J

2004-01-01

Mass coral bleaching is linked to elevated sea surface temperatures, 1-2 degrees C above average, during periods of intense light. These conditions induce the expulsion of zooxanthellae from the coral host in response to photosynthetic damage in the algal symbionts. The mechanism that triggers this release has not been clearly established and to further our knowledge of this process, fluorescence rise kinetics have been studied for the first time. Corals that were exposed to elevated temperature (33 degrees C) and light (280 mumol photons m(-2) s(-1)), showed distinct changes in the fast polyphasic induction of chlorophyll-a fluorescence, indicating biophysical changes in the photochemical processes. The fluorescence rise over the first 2000ms was monitored in three species of corals for up to 8 h, with a PEA fluorometer and an imaging-PAM. Pocillopora damicornis showed the least impact on photosynthetic apparatus, while Acropora nobilis was the most sensitive, with Cyphastrea serailia intermediate between the other two species. A. nobilis showed a remarkable capacity for recovery from bleaching conditions. For all three species, a steady decline in the slope of the initial rise and the height of the J-transient was observed, indicating the loss of functional Photosystem II (PS II) centres under elevated-temperature conditions. A significant loss of PS II centres was confirmed by a decline in photochemical quenching when exposed to bleaching stress. Non-photochemical quenching was identified as a significant mechanism for dissipating excess energy as heat under the bleaching conditions. Photophosphorylation could explain this decline in PS II activity. State transitions, a component of non-photochemical quenching, was a probable cause of the high non-photochemical quenching during bleaching and this mechanism is associated with the phosphorylation-induced dissociation of the light harvesting complexes from the PS II reaction centres. This reversible process may account for the coral recovery, particularly in A. nobilis.

Effect Of Inorganic, Synthetic And Naturally Occurring Chelating Agents On Fe(II) Mediated Advanced Oxidation Of Chlorophenols

EPA Science Inventory

This study examines the feasibility and application of Advanced Oxidation Technologies (AOTs) for the treatment of chlorophenols that are included in US EPA priority pollutant list. A novel class of sulfate/hydroxyl radical-based homogeneous AOTs (Fe(II)/PS, Fe(II)/PMS, Fe(II)/H...

The accuracy of the lateral vertebral notch-referred pedicle screw insertion technique in subaxial cervical spine: a human cadaver study.

PubMed

Luo, Jiaquan; Wu, Chunyang; Huang, Zhongren; Pan, Zhimin; Li, Zhiyun; Zhong, Junlong; Chen, Yiwei; Han, Zhimin; Cao, Kai

2017-04-01

This is a cadaver specimen study to confirm new pedicle screw (PS) entry point and trajectory for subaxial cervical PS insertion. To assess the accuracy of the lateral vertebral notch-referred PS insertion technique in subaxial cervical spine in cadaver cervical spine. Reported morphometric landmarks used to guide the surgeon in PS insertion show significant variability. In the previous study, we proposed a new technique (as called "notch-referred" technique) primarily based on coronal multiplane reconstruction images (CMRI) and cortical integrity after PS insertion in cadavers. However, the PS position in cadaveric cervical segment was not confirmed radiologically. Therefore, the difference between the pedicle trajectory and the PS trajectory using the notch-referred technique needs to be illuminated. Twelve cadaveric cervical spines were conducted with PS insertion using the lateral vertebral notch-referred technique. The guideline for entry point and trajectory for each vertebra was established based on the morphometric data from our previous study. After 3.5-mm diameter screw insertion, each vertebra was dissected and inspected for pedicle trajectory by CT scan. The pedicle trajectory and PS trajectory were measured and compared in axial plane. The perforation rate was assessed radiologically and was graded from ideal to unacceptable: Grade 0 = screw in pedicle; Grade I = perforation of pedicle wall less than one-fourth of the screw diameter; Grade II = perforation more than one-fourth of the screw diameter but less than one-second; Grade III = perforation more than one-second outside of the screw diameter. In addition, pedicle width between the acceptable and unacceptable screws was compared. A total of 120 pedicle screws were inserted. The perforation rate of pedicle screws was 78.3% in grade 0 (excellent PS position), 10.0% in grade I (good PS position), 8.3% in grade II (fair PS position), and 3.3% in grade III (poor PS position). The overall accepted accuracy of pedicle screws was 96.7% (Grade 0 + Grade I + Grade II), and only 3.3% had critical breach. There was no statistical difference between the pedicle trajectory and PS trajectory (p > 0.05). Compared to the pedicle width (4.4 ± 0.7 mm) in acceptably inserted screw, the unacceptably screw is 3.2 ± 0.3 mm which was statistically different (p < 0.05). The accuracy of the notch-referred PS insertion in cadaveric subaxial cervical spine is satisfactory.

Responses of the photosynthetic electron transport system to excess light energy caused by water deficit in wild watermelon.

PubMed

Sanda, Satoko; Yoshida, Kazuo; Kuwano, Masayoshi; Kawamura, Tadayuki; Munekage, Yuri Nakajima; Akashi, Kinya; Yokota, Akiho

2011-07-01

In plants, drought stress coupled with high levels of illumination causes not only dehydration of tissues, but also oxidative damage resulting from excess absorbed light energy. In this study, we analyzed the regulation of electron transport under drought/high-light stress conditions in wild watermelon, a xerophyte that shows strong resistance to this type of stress. Under drought/high-light conditions that completely suppressed CO(2) fixation, the linear electron flow was diminished between photosystem (PS) II and PS I, there was no photoinhibitory damage to PS II and PS I and no decrease in the abundance of the two PSs. Proteome analyses revealed changes in the abundance of protein spots representing the Rieske-type iron-sulfur protein (ISP) and I and K subunits of NAD(P)H dehydrogenase in response to drought stress. Two-dimensional electrophoresis and immunoblot analyses revealed new ISP protein spots with more acidic isoelectric points in plants under drought stress. Our findings suggest that the modified ISPs depress the linear electron transport activity under stress conditions to protect PS I from photoinhibition. The qualitative changes in photosynthetic proteins may switch the photosynthetic electron transport from normal photosynthesis mode to stress-tolerance mode. Copyright © Physiologia Plantarum 2011.

Iron Tolerant Cyanobacteria as an Effective Tool to Study Early Evolution of Life and the Development of Biosignatures

NASA Technical Reports Server (NTRS)

Brown, Igor; Mummey, Daniel; Sarkisova, Svetlana; Allen, Carlton; McKay, David S.

2006-01-01

We are currently conducting preliminary studies on the diversity of iron-tolerant cyanobacteria (CB) isolated from iron-depositing hot springs in and around Yellowstone National Park (WY, USA). In conclusion, there is no consensus on the divergence of cyanobacteria from a common ancestor for either anoxygenic or oxygenic phototrophs. Anoxygenic photosynthesis may have provided energy for the common ancestor, but it is unclear what environmental pressure induced the evolving of oxygenic phototrophs. It is supposed, however, that predecessors of contemporary CB were capable of oxidizing various substrates other than water , and it is likely that Fe2+ could be one of those substrates . If that were the case, the work of entire photosystems in Precambrian cyanobacteria and/or in their predecessors could follow three scenarios (at least): 1) ferrous iron may have been oxidized in PS II but without significant effects on oxygen evolution, and environmental iron could have been oxidized either enzymatically or chemically; 2) ferrous iron may have been oxidized only enzymatically by PS II, accompanied by the repression of O2 evolution; or 3) ferrous iron may have been oxidized by PS I upon the prevalence of anoxygenic photosynthesis or without any effect on PS II. All of these scenarios will be the subject of our future studies with the aim to understand which line-ages of CB could be typical for Precambrian time.

Viscosity and medium effects on the fluorescence and photochemical behaviour of some aryl chalcones

NASA Astrophysics Data System (ADS)

Ebeid, El-Zeiny M.; Abdel-Kader, Mahmood H.; Issa, Raafat M.; El-Daly, Samy A.

1988-05-01

The emission, excitation and absorption spectra toghether with the fluorescence and photochemical quantum yields of some chalcone derivatives have been studied in organic solvents and micellar and microemulsion media. Both 4-[2-(2-pyridyl)ethenyl] ( I) and 4-[2-(4-pyridyl)ethenyl ( II) chalcones show large positive solvatochromic effects. The fluorescence quantum yields increase substantially as the medium viscosity increases with a subsequent decrease in the photochemical quatum yield. Compounds I and II undergo excited-state molecular aggregation in concentrated solutions giving excimer-like emission that coincides with emission from crystalline samples. The enthalpies of photoassociation have been estimated. The chalcone derivative I acts as an efficient quencher of the fluorescence of the laser dye 1,4-bis (β-pyridyl-2-vinyl)benzene via a long-range mechanism. The excited-state lifetimes of both I and II are short and at 20°C their τ values are less than 800 ps.

Measurement of the B(0) lifetime with partially reconstructed B(0)-->D(-)l(+)nu(l) decays.

PubMed

Aubert, B; Boutigny, D; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, G P; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Clark, A R; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kral, J F; LeClerc, C; Levi, M E; Lynch, G; Oddone, P J; Pripstein, M; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Harrison, T J; Hawkes, C M; Knowles, D J; O'Neale, S W; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Kunze, M; Lewandowski, B; Peters, K; Schmuecker, H; Steinke, M; Barlow, N R; Bhimji, W; Chevalier, N; Clark, P J; Cottingham, W N; Foster, B; Mackay, C; Wilson, F F; Abe, K; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Jolly, S; McKemey, A K; Blinov, V E; Bukin, A D; Bukin, D A; Buzykaev, A R; Golubev, V B; Ivanchenko, V N; Korol, A A; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Telnov, V I; Yushkov, A N; Best, D; Chao, M; Kirkby, D; Lankford, A J; Mandelkern, M; McMahon, S; Stoker, D P; Arisaka, K; Buchanan, C; Chun, S; MacFarlane, D B; Prell, S; Rahatlou, Sh; Raven, G; Sharma, V; Campagnari, C; Dahmes, B; Hart, P A; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beringer, J; Eisner, A M; Grothe, M; Heusch, C A; Lockman, W S; Pulliam, T; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Metzler, S; Oyang, J; Porter, F C; Ryd, A; Samuel, A; Weaver, M; Yang, S; Zhu, R Y; Devmal, S; Geld, T L; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Barillari, T; Bloom, P; Dima, M O; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; van Hoek, W C; Blouw, J; Harton, J L; Krishnamurthy, M; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Dubitzky, R S; Hauke, A; Maly, E; Müller-Pfefferkorn, R; Otto, S; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Ferrag, S; T'Jampens, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Anjomshoaa, A; Bernet, R; Khan, A; Lavin, D; Muheim, F; Playfer, S; Swain, J E; Tinslay, J; Falbo, M; Borean, C; Bozzi, C; Dittongo, S; Piemontese, L; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Xie, Y; Zallo, A; Bagnasco, S; Buzzo, A; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Pastore, F C; Patrignani, C; Pia, M G; Robutti, E; Santroni, A; Tosi, S; Morii, M; Bartoldus, R; Hamilton, R; Mallik, U; Cochran, J; Crawley, H B; Fischer, P-A; Lamsa, J; Meyer, W T; Rosenberg, E I; Grosdidier, G; Hast, C; Höcker, A; Lacker, H M; Laplace, S; Lepeltier, V; Lutz, A M; Plaszczynski, S; Schune, M H; Trincaz-Duvoid, S; Wormser, G; Bionta, R M; Brigljević, V; Lange, D J; Mugge, M; van Bibber, K; Wright, D M; Bevan, A J; Fry, J R; Gabathuler, E; Gamet, R; George, M; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Gunawardane, N J W; Nash, J A; Sanders, P; Smith, D; Azzopardi, D E; Back, J J; Bellodi, G; Dixon, P; Harrison, P F; Potter, R J L; Shorthouse, H W; Strother, P; Vidal, P B; Cowan, G; George, S; Green, M G; Kurup, A; Marker, C E; McGrath, P; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Brown, D; Davis, C L; Allison, J; Barlow, R J; Boyd, J T; Forti, A C; Fullwood, J; Jackson, F; Lafferty, G D; Savvas, N; Weatherall, J H; Williams, J C; Farbin, A; Jawahery, A; Lillard, V; Olsen, J; Roberts, D A; Schieck, J R; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Staengle, H; Willocq, S; Brau, B; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Milek, M; Patel, P M; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Nief, J Y; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; LoSecco, J M; Alsmiller, J R G; Gabriel, T A; Brau, J; Frey, R; Grauges, E; Iwasaki, M; Sinev, N B; Strom, D; Colecchia, F; Dal Corso, F; Dorigo, A; Galeazzi, F; Margoni, M; Michelon, G; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Torassa, E; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; Le Diberder, F; Leruste, Ph; Ocariz, J; Roos, L; Stark, J; Manfredi, P F; Re, V; Speziali, V; Frank, E D; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Campagna, E; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Simi, G; Triggiani, G; Walsh, J; Haire, M; Judd, D; Paick, K; Turnbull, L; Wagoner, D E; Albert, J; Elmer, P; Lu, C; Miftakov, V; Schaffner, S F; Smith, A J S; Tumanov, A; Varnes, E W; Cavoto, G; Del Re, D; Faccini, R; Ferrarotto, F; Ferroni, F; Lamanna, E; Mazzoni, M A; Morganti, S; Piredda, G; Safai Tehrani, F; Serra, M; Voena, C; Christ, S; Waldi, R; Adye, T; De Groot, N; Franek, B; Geddes, N I; Gopal, G P; Xella, S M; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; Hamel de Monchenault, G; Kozanecki, W; Langer, M; London, G W; Mayer, B; Serfass, B; Vasseur, G; Yèche, Ch; Zito, M; Purohit, M V; Singh, H; Weidemann, A W; Yumiceva, F X; Adam, I; Aston, D; Berger, N; Boyarski, A M; Calderini, G; Convery, M R; Coupal, D P; Dong, D; Dorfan, J; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Haas, T; Halyo, V; Himel, T; Hryn'ova, T; Huffer, M E; Innes, W R; Jessop, C P; Kelsey, M H; Kim, P; Kocian, M L; Langenegger, U; Leith, D W G S; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Menke, S; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Quinn, H; Ratcliff, B N; Robertson, S H; Roodman, A; Salnikov, A A; Schietinger, T; Schindler, R H; Schwiening, J; Snyder, A; Soha, A; Spanier, S M; Stelzer, J; Su, D; Sullivan, M K; Tanaka, H A; Va'vra, J; Wagner, S R; Weinstein, A J R; Wisniewski, W J; Wright, D H; Young, C C; Burchat, P R; Cheng, C H; Meyer, T I; Roat, C; Henderson, R; Bugg, W; Cohn, H; Izen, J M; Kitayama, I; Lou, X C; Bianchi, F; Bona, M; Gamba, D; Bosisio, L; Della Ricca, G; Lanceri, L; Poropat, P; Vuagnin, G; Panvini, R S; Brown, C M; Jackson, P D; Kowalewski, R; Roney, J M; Band, H R; Charles, E; Dasu, S; Eichenbaum, A M; Hu, H; Johnson, J R; Liu, R; Di Lodovico, F; Pan, Y; Prepost, R; Scott, I J; Sekula, S J; von Wimmersperg-Toeller, J H; Wu, S L; Yu, Z; Kordich, T M B; Neal, H

2002-07-01

The B(0) lifetime was measured with a sample of 23 million BB pairs collected by the BABAR detector at the PEP-II e(+)e(-) storage ring during 1999 and 2000. Events from the semileptonic decay B(0)-->D(*-)l(+)nu(l) have been selected with a partial reconstruction method in which only the charged lepton and the slow pi from the D*--->D(0)pi(-) decay are reconstructed. The result is tau(B(0)) = 1.529+/-0.012(stat)+/-0.029(syst) ps.

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

Kapusta, P.; Kisielewski, B.

In this paper the overvoltage protection modules (OVP) for the power supply (PS) system of the Belle II pixel detector (PXD) are described. The aim of the OVP is to protect the detector and associated electronics against overvoltage conditions. Most critical in the system are voltages supplying the front-end ASICs. The PXD detector consists of the DEPFET sensor modules with integrated chips like the Drain Current Digitizer, the Switcher and the Data Handling Processor. These chips, implemented in modern sub-micron technologies, are quite vulnerable to variations in the supply voltages. The PXD will be placed in the Belle II experimentmore » as close as possible to the interaction point, where access during experiment is very limited or even impossible, thus the PS and OVP systems exploit the remote-sensing method. Overvoltage conditions are due to failures of the PS itself, wrong setting of the output voltages or transient voltages coming out of hard noisy environment of the experiment. The OVP modules are parts of the PS modules. For powering the PXD 40 PS modules are placed 15 m outside the Belle II spectrometer. Each one is equipped with the OVP board. All voltages (22) are grouped in 4 domains: Analog, Digital, Steering and Gate which have independent grounds. The OVP boards are designed from integrated circuits from Linear Technology. All configurations were simulated with the Spice program. The control electronics is designed in a Xilinx CPLD. Two types of integrated circuits were used. LT4356 surge stopper protects loads from high voltage transients. The output voltages are limited to a safe value and also protect loads against over current faults. For less critical voltages, the LTC2912 voltage monitors are used that detect under-voltage and overvoltage events. It has to be noted that the OVP system is working independently of any other protection of the PS system, which increases its overall reliability. (authors)« less

A search for ultraviolet circumstellar gas absorption features in alpha Piscis Austrinus (Fomalhaut), a possible Beta Pictoris-like system

NASA Technical Reports Server (NTRS)

Cheng, K.-P.; Bruhweiler, Fred C.; Kondo, Yoji

1994-01-01

Archival high-dispersion International Ultraviolet Explorer (IUE) spectra have been used to search for circumstellar gas absorption features in alpha PsA (A3 V), a nearby (6.7 pc) proto-planetary system candidate. Recent sub-millimeter mapping observations around the region of alpha PsA indicate a spatially resolved dust disk like the one seen around Beta Pic. To determine how closely this putative disk resembles that of Beta Pic, we have searched for signatures of circumstellar gaseous absorption in all the available IUE high-dispersion data of alpha PsA. Examination of co-added IUE spectra shows weak circumstellar absorptions from excited levels in the resonance multiplet of Fe II near 2600 A. We also conclude that the sharp C I feature near 1657 A, previously identified as interstellar absorption toward alpha PsA, likely has a circumstellar origin. However, because the weakness of these absorption features, we will consider the presence of circumstellar gas as tentative and should be verified by using the Goddard High-Resolution Spectrograph aboard the Hubble Space Telescope. No corresponding circumstellar absorption is detected in higher ionization Fe III and Al III. Since the collisionally ionized nonphotospheric Al III resonance absorption seen in Beta Pic is likely formed close to the stellar surface, its absence in the UV spectra of alpha PsA could imply that, in contrast with Beta Pic, there is no active gaseous disk infall onto the central star. In the alpha PsA gaseous disk, if we assume a solar abundance for iron and all the iron is in the form of Fe II, plus a disk temperature of 5000 K, the Fe II UV1 absorption at 2611.8743 A infers a total hydrogen column density along the line of sight through the circumstellar disk of N(H) approximately equals 3.8 x 10(exp 17)/cm.

Morphology, drug release, antibacterial, cell proliferation, and histology studies of chamomile-loaded wound dressing mats based on electrospun nanofibrous poly(ɛ-caprolactone)/polystyrene blends.

PubMed

Motealleh, Behrooz; Zahedi, Payam; Rezaeian, Iraj; Moghimi, Morvarid; Abdolghaffari, Amir Hossein; Zarandi, Mohammad Amin

2014-07-01

For the first time, it has been tried to achieve optimum conditions for electrospun poly(ε-caprolactone)/polystyrene (PCL/PS) nanofibrous samples as active wound dressings containing chamomile via D-optimal design approach. In this work, systematic in vitro and in vivo studies were carried out by drug release rate, antibacterial and antifungal evaluations, cell culture, and rat wound model along with histology observation. The optimized samples were prepared under the following electrospinning conditions: PCL/PS ratio (65/35), PCL concentration 9%(w/v), PS concentration 14%(w/v), distance between the syringe needle tip and the collector 15.5 cm, applied voltage 18 kV, and solution flow rate 0.46 mL h(-1) . The FE-SEM micrographs showed electrospun PCL/PS (65/35) nanofibrous sample containing 15% chamomile had a minimum average diameter (∼175 nm) compared to the neat samples (∼268 nm). The drug released resulted in a gradual and high amount of chamomile from the optimized PCL/PS nanofibrous sample (∼70%) in respect to PCL and PS nanofibers after 48 h. This claim was also confirmed by antibacterial and antifungal evaluations in which an inhibitory zone with a diameter of about 7.6 mm was formed. The rat wound model results also indicated that the samples loaded with 15% chamomile extract were remarkably capable to heal the wounds up to 99 ± 0.5% after 14 days post-treatment periods. The adhesion of mesenchymal stem cells and their viability on the optimized samples were confirmed by MTT analysis. Also, the electrospun nanofibrous mats based on PCL/PS (65/35) showed a high efficiency in the wound closure and healing process compared to the reference sample, PCL/PS nanofibers without chamomile. Finally, the histology analysis revealed that the formation of epithelial tissues, the lack of necrosis and collagen fibers accumulation in the dermis tissues for the above optimized samples. © 2013 Wiley Periodicals, Inc.

Emission of positronium in a nanometric PMMA film

NASA Astrophysics Data System (ADS)

Palacio, C. A.; De Baerdemaeker, J.; Van Thourhout, D.; Dauwe, C.

2008-10-01

Positron beam experiments have been performed for the first time on a self-supporting polymethyl metacrylate (PMMA) film of 310 nm-thick made by spin coating. The positronium (Ps) emission from the PMMA surface is studied as a function of the positron implantation energy by using Doppler profile spectroscopy and Compton-to-peak ratio analysis. When the sample and the Ge-detector are perpendicular to the positron beam, the emission of para-positronium ( p-Ps) is detected as a narrow central peak. By rotating the sample 45° with respect to the beam, the emission of p-Ps is detected as a blue-shifted fly-away peak. The bulk Ps fraction, the efficiency for the emission of Ps by picking up an electron from the surface, and the diffusion lengths of positrons (thermal and or epithermal), p-Ps and ortho-positronium ( o-Ps) are obtained.

Morphological and physical characterization of poly(styrene-isobutylene-styrene) block copolymers and ionomers thereof

NASA Astrophysics Data System (ADS)

Baugh, Daniel Webster, III

Poly(styrene-isobutylene-styrene) block copolymers made by living cationic polymerization using a difunctional initiator and the sequential monomer addition technique were analyzed using curve-resolution software in conjunction with high-resolution GPC. Fractional precipitation and selective solvent extraction were applied to a representative sample in order to confirm the identity of contaminating species. The latter were found to be low molecular weight polystyrene homopolymer, diblock copolymer, and higher molecular weight segmented block copolymers formed by intermolecular electrophilic aromatic substitution linking reactions occurring late in the polymerization of the styrene outer blocks. Solvent-cast films of poly(styrene-isobutylene-styrene) (PS-PIB-PS) block copolymers and block ionomers were analyzed using small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). Four block copolymer samples with center block molecular weights of 52,000 g/mol and PS volume fractions (o sbPS) ranging from 0.17 to 0.31 were studied. All samples exhibited hexagonally packed cylinders of PS within the PIB matrix. Cylinder spacing was in the range 32 to 36 nm for most samples, while cylinder diameters varied from 14 to 21 nm. Porod analysis of the scattering data indicated the presence of isolated phase mixing and sharp phase boundaries. PS-PIB-PS block copolymers and ionomers therefrom were analyzed using dynamic mechanical analysis (DMA) and tensile testing. The study encompassed five block copolymer samples with similar PIB center blocks with molecular weights of approx52,000 g/mol and PS weight fractions ranging from 0.127 to 0.337. Ionomers were prepared from two of these materials by lightly sulfonating the PS outer blocks. Sulfonation levels varied from 1.7 to 4.7 mol % and the sodium and potassium neutralized forms were compared to the parent block copolymers. Dynamic mechanical analysis (DMA) of the block copolymer films indicated the existence of a third phase attributed to PIB chains near the PS domain interface which experience reduced mobility due to their firm attachment to the hard PS domain. The relative amount of this phase decreased in samples with larger PS blocks, while the temperature of the associated transition increased. Tensile testing showed increased tensile strength but decreased elongation at break with larger PS blocks. DMA of the ionomers indicated improved dynamic modulus at temperatures above 100spcirc$C. Tensile testing of the ionomers indicated slight improvements in tensile strength with little loss in elongation at break. PS-PIB-PS block copolymer ionomer (BCP01, center block molecular weight = 53,000 g/mole; 25.5 wt % polystyrene, 4.7% sulfonation of phenyl units, 100% neutralized with KOH) was compounded with various organic and inorganic acid salts of 2-ethylhexyl-p-dimethyl aminobenzoate (ODAB) to explore the efficacy of these compounds as ionic plasticizers. (Abstract shortened by UMI.)

Study of white light emission from ZnS/PS composite system

NASA Astrophysics Data System (ADS)

Wang, Caifeng; Li, Qingshan; Lu, Lei; Zhang, Lichun; Qi, Hongxia

2007-09-01

ZnS films were deposited by pulsed laser deposition (PLD) on porous silicon (PS) substrates formed by electrochemical anodization of p-type (100) silicon wafer. The photoluminescence (PL) spectra of ZnS/PS composites were measured at room temperature. Under different excitation wavelengths, the relative integrated intensities of the red light emission from PS layers and the blue-green emission from ZnS films had different values. After samples were annealed in vacuum at different temperatures (200, 300, and 400 Celsius degree) for 30 min respectively, a new green emission located at around 550 nm appeared in the PL spectra of all ZnS/PS samples, and all of the ZnS/PS composites had a broad PL band (450-700 nm) in the visible region, exhibiting intensively white light emission.

Separation and determination of minor photosynthetic pigments by reversed-phase HPLC with minimal alteration of chlorophylls.

PubMed

Nakamura, A; Watanabe, T

2001-04-01

Reversed-phase HPLC conditions for separation of chlorophyll (Chl) a, Chl a' (the C132-epimer of Chl a), pheophytin (Pheo) a (the primary electron acceptor of photosystem (PS) II), and phylloquinone (PhQ) (the secondary electron acceptor of PS 1), have been developed. Pigment extraction conditions were optimized in terms of pigment alteration and extraction efficiency. Pigment composition analysis of light-harvesting complex II, which would not contain Chl a' nor Pheo a, showed the Chl a'/Chl a ratio of 3-4 x 10(-4) and the Pheo a/Chl a ratio of 4-5 x 10(-4), showing that the conditions developed here were sufficiently inert for Chl analysis. Preliminary analysis of thylakoid membranes with this analytical system gave the PhQ/Chl a' ratio of 0.58 +/- 0.03 (n = 4), in line with the stoichiometry of one molecule of Chl a' per PS I.

The relationship between the Tg depression and the speeding up of physical aging in polystyrene/gold nanocomposites

NASA Astrophysics Data System (ADS)

Boucher, Virginie M.; Cangialosi, Daniele; Alegria, Angel; Colmenero, Juan

2011-03-01

The effect of gold nanoparticles on the segmental dynamics, glass transition (Tg) and physical aging of polystyrene (PS) was studied in PS/Gold nanocomposites samples containing 5 and 15 wt.% of 60 nm spherical gold nanoparticles, surface-treated with thiolated-PS. While the segmental dynamics of PS, as assessed by broadband dielectric spectroscopy (BDS), was found to be unchanged in presence of gold nanoparticles, the calorimetric Tg of PS was shown to decrease with increasing the amount of nanoparticles in the samples. Furthermore, the physical aging of PS, monitored by measuring the enthalpy relaxation below Tg by means of DSC, was shown to speed up with increasing the nanoparticles weight fraction, i.e. the amount of PS/Gold interface in the hybrid material. Thus, the main conclusion of our work is that PS molecular mobility and out-of-equilibrium dynamics are decoupled in these nanocomposites. The significant effect of the amount of PS/Gold interface on both the physical aging rate of PS and the calorimetric Tg depression are quantitatively accounted for by a model based on the diffusion of free volume holes towards polymer interfaces, with a diffusion coefficient depending only on the molecular mobility.

Tunable PhoXonic Band Gap Materials from Self-Assembly of Block Copoliymers and Colloidal Nanocrystals (NBIT Phase II)

DTIC Science & Technology

2011-05-06

electric fields. For that, we are going to use PS - b - P2VP block copolymers as a model system, utilizing the quite versatile chemistry of the P2VP ...displays. Our efforts at Hanyang have focused on tunable PBG materials self-assembled from polystyrene- b -poly(2-vinyl pyridine) ( PS - b - P2VP ) block...small angle x-ray scattering measurements during swelling of low molecular weight PS - P2VP polymers at the Cornell High Energy Synchrotron Source

Removal of Ca 2+ from the Oxygen-Evolving Complex in Photosystem II Has Minimal Effect on the Mn 4O 5 Core Structure: A Polarized Mn X-ray Absorption Spectroscopy Study

DOE PAGES

Lohmiller, Thomas; Shelby, Megan L.; Long, Xi; ...

2015-05-19

We studied Ca 2+ -depleted and Ca 2+ -reconstituted spinach photosystem II using polarized X-ray absorption spectroscopy of oriented PS II preparations to investigate the structural and functional role of the Ca 2+ ion in the Mn 4O 5Ca cluster of the oxygen-evolving complex (OEC). Samples were prepared by low pH/citrate treatment as one-dimensionally ordered membrane layers and poised in the Ca 2+ -depleted S 1 (S 1') and S 2 (S 2') states, the S 2'Y Z• state, at which point the catalytic cycle of water oxidation is inhibited, and the Ca 2+ -reconstituted S 1 state. Polarized Mnmore » K-edge XANES and EXAFS spectra exhibit pronounced dichroism. Polarized EXAFS data of all states of Ca 2+ -depleted PS II investigated show only minor changes in distances and orientations of the Mn-Mn vectors compared to the Ca 2+ -containing OEC, which may be attributed to some loss of rigidity of the core structure. Thus, removal of the Ca 2+ ion does not lead to fundamental distortion or rearrangement of the tetranuclear Mn cluster, which indicates that the Ca 2+ ion in the OEC is not critical for structural maintenance of the cluster, at least in the S 1 and S 2 states, but fulfills a crucial catalytic function in the mechanism of the water oxidation reaction. On the basis of this structural information, reasons for the inhibitory effect of Ca 2+ removal are discussed, attributing to the Ca 2+ ion a fundamental role in organizing the surrounding (substrate) water framework and in proton-coupled electron transfer to Y Z• (D1-Tyr161).« less

Removal of Ca(2+) from the Oxygen-Evolving Complex in Photosystem II Has Minimal Effect on the Mn4O5 Core Structure: A Polarized Mn X-ray Absorption Spectroscopy Study.

PubMed

Lohmiller, Thomas; Shelby, Megan L; Long, Xi; Yachandra, Vittal K; Yano, Junko

2015-10-29

Ca(2+)-depleted and Ca(2+)-reconstituted spinach photosystem II was studied using polarized X-ray absorption spectroscopy of oriented PS II preparations to investigate the structural and functional role of the Ca(2+) ion in the Mn4O5Ca cluster of the oxygen-evolving complex (OEC). Samples were prepared by low pH/citrate treatment as one-dimensionally ordered membrane layers and poised in the Ca(2+)-depleted S1 (S1') and S2 (S2') states, the S2'YZ(•) state, at which point the catalytic cycle of water oxidation is inhibited, and the Ca(2+)-reconstituted S1 state. Polarized Mn K-edge XANES and EXAFS spectra exhibit pronounced dichroism. Polarized EXAFS data of all states of Ca(2+)-depleted PS II investigated show only minor changes in distances and orientations of the Mn-Mn vectors compared to the Ca(2+)-containing OEC, which may be attributed to some loss of rigidity of the core structure. Thus, removal of the Ca(2+) ion does not lead to fundamental distortion or rearrangement of the tetranuclear Mn cluster, which indicates that the Ca(2+) ion in the OEC is not critical for structural maintenance of the cluster, at least in the S1 and S2 states, but fulfills a crucial catalytic function in the mechanism of the water oxidation reaction. On the basis of this structural information, reasons for the inhibitory effect of Ca(2+) removal are discussed, attributing to the Ca(2+) ion a fundamental role in organizing the surrounding (substrate) water framework and in proton-coupled electron transfer to YZ(•) (D1-Tyr161).

Ping-Pong Energy Transfer in a Boron Dipyrromethane Containing Pt(II)-Schiff Base Complex: Synthesis, Photophysical Studies, and Anti-Stokes Shift Increase in Triplet-Triplet Annihilation Upconversion.

PubMed

Razi, Syed S; Koo, Yun Hee; Kim, Woojae; Yang, Wenbo; Wang, Zhijia; Gobeze, Habtom; D'Souza, Francis; Zhao, Jianzhang; Kim, Dongho

2018-05-07

A boron dipyrromethane (BDP)-containing Pt(II)-Schiff base complex (Pt-BDP), showing ping-pong singlet-triplet energy transfer, was synthesized, and the detailed photophysical properties were investigated using various steady-state and time-resolved transient spectroscopies. Femtosecond/nanosecond transient absorption spectroscopies demonstrated that, upon selective excitation of the BDP unit in Pt-BDP at 490 nm, Förster resonance energy transfer from the BDP unit to the Pt(II) coordination center occurred (6.7 ps), accompanied by an ultrafast intersystem crossing at the Pt(II) coordination center (<1 ps) and triplet-triplet energy transfer back to the BDP moiety (148 ps). These processes generated a triplet state localized at BDP, and the lifetime was 103.2 μs, much longer than the triplet-state lifetime of Pt-Ph (3.5 μs), a complex without the BDP moiety. Finally, Pt-BDP was used as a triplet photosensitizer for triplet-triplet annihilation (TTA) upconversion through selective excitation of the BDP unit or the Pt(II) coordination center at lower excitation energy. An upconversion quantum yield of up to 10% was observed with selective excitation of the BDP moiety, and a large anti-Stokes shift of 0.65 eV was observed upon excitation of the lower-energy band of the Pt(II) coordination center. We propose that using triplet photosensitizers with the ping-pong energy-transfer process may become a useful method for increasing the anti-Stokes shift of TTA upconversion.

Towards a more ecologically relevant assessment of the impact of heavy metals on the photosynthesis of the seagrass, Zostera capricorni.

PubMed

Macinnis-Ng, Catriona M O; Ralph, Peter J

2002-01-01

This in situ study used photosynthetic activity (measured as chlorophyll a fluorescence) and photosynthetic pigment concentrations to assess the effect of copper, cadmium, lead and zinc on the seagrass Zostera capricorni. Custom-made portable in situ exposure (PIE) chambers were developed so seagrasses could be dosed within the meadow. Z capricorni was exposed to 0.1 and I mg l(-1) of metal solutions for 10 h. During this time and for the subsequent four-day recovery period, the effective quantum yield of photosystem II (PS II) (deltaF/Fm') was measured. While the results were variable, copper and zinc exposed samples had a depressed deltaF/Fm' during the exposure period. Samples exposed to zinc recovered to pre-exposure levels but those exposed to copper did not. Cadmium and lead did not impact on the chlorophyll a fluorescence and the chlorophyll pigment data supported these findings. This study presents an innovative new application of chlorophyll a fluorescence stress assessment.

Analytical variables affecting analysis of F2-isoprostanes and F4-neuroprostanes in human cerebrospinal fluid by gas chromatography/mass spectrometry.

PubMed

Yen, Hsiu-Chuan; Wei, Hsing-Ju; Chen, Ting-Wei

2013-01-01

F2-isoprostanes (F2-IsoPs) are a gold marker of lipid peroxidation in vivo, whereas F4-neuroprostanes (F4-NPs) measured in cerebrospinal fluid (CSF) or brain tissue selectively indicate neuronal oxidative damage. Gas chromatography/negative-ion chemical-ionization mass spectrometry (GC/NICI-MS) is the most sensitive and robust method for quantifying these compounds, which is essential for CSF samples because abundance of these compounds in CSF is very low. The present study revealed potential interferences on the analysis of F2-IsoPs and F4-NPs in CSF by GC/NICI-MS due to the use of improper analytical methods that have been employed in the literature. First, simultaneous quantification of F2-IsoPs and F4-NPs in CSF samples processed for F4-NPs analysis could cause poor chromatographic separation and falsely higher F2-IsoPs values for CSF samples with high levels of F2-IsoPs and F4-NPs. Second, retention of unknown substances in GC columns from CSF samples during F4-NPs analysis and from plasma samples during F2-IsoPs analysis might interfere with F4-NPs analysis of subsequent runs, which could be solved by holding columns at a high temperature for a period of time after data acquisition. Therefore, these special issues should be taken into consideration when performing analysis of F2-IsoPs and F4-NPs in CSF to avoid misleading results.

Analytical Variables Affecting Analysis of F2-Isoprostanes and F4-Neuroprostanes in Human Cerebrospinal Fluid by Gas Chromatography/Mass Spectrometry

PubMed Central

Yen, Hsiu-Chuan; Wei, Hsing-Ju; Chen, Ting-Wei

2013-01-01

F2-isoprostanes (F2-IsoPs) are a gold marker of lipid peroxidation in vivo, whereas F4-neuroprostanes (F4-NPs) measured in cerebrospinal fluid (CSF) or brain tissue selectively indicate neuronal oxidative damage. Gas chromatography/negative-ion chemical-ionization mass spectrometry (GC/NICI-MS) is the most sensitive and robust method for quantifying these compounds, which is essential for CSF samples because abundance of these compounds in CSF is very low. The present study revealed potential interferences on the analysis of F2-IsoPs and F4-NPs in CSF by GC/NICI-MS due to the use of improper analytical methods that have been employed in the literature. First, simultaneous quantification of F2-IsoPs and F4-NPs in CSF samples processed for F4-NPs analysis could cause poor chromatographic separation and falsely higher F2-IsoPs values for CSF samples with high levels of F2-IsoPs and F4-NPs. Second, retention of unknown substances in GC columns from CSF samples during F4-NPs analysis and from plasma samples during F2-IsoPs analysis might interfere with F4-NPs analysis of subsequent runs, which could be solved by holding columns at a high temperature for a period of time after data acquisition. Therefore, these special issues should be taken into consideration when performing analysis of F2-IsoPs and F4-NPs in CSF to avoid misleading results. PMID:23957004

Mutation of Photosystem II D1 protein that empower efficient phenotypes of Chlamydomonas Reinhardtii under extreme environment in space

USDA-ARS?s Scientific Manuscript database

Oxygenic photosynthesis involves capture and conversion of light energy into chemical energy, a process fundamental to life including plant productivity on Earth. Photosynthetic electron transport is catalyzed by two photochemical reaction centres in series, photosystem II (PS II) and photosytem I (...

The effect of phosphatidylserine administration on memory and symptoms of attention-deficit hyperactivity disorder: a randomised, double-blind, placebo-controlled clinical trial.

PubMed

Hirayama, S; Terasawa, K; Rabeler, R; Hirayama, T; Inoue, T; Tatsumi, Y; Purpura, M; Jäger, R

2014-04-01

Attention-deficit hyperactivity disorder (ADHD) is the most commonly diagnosed behavioural disorder of childhood, affecting 3-5% of school-age children. The present study investigated whether the supplementation of soy-derived phosphatidylserine (PS), a naturally occurring phospholipid, improves ADHD symptoms in children. Thirty six children, aged 4-14 years, who had not previously received any drug treatment related to ADHD, received placebo (n = 17) or 200 mg day(-1) PS (n = 19) for 2 months in a randomised, double-blind manner. Main outcome measures included: (i) ADHD symptoms based on DSM-IV-TR; (ii) short-term auditory memory and working memory using the Digit Span Test of the Wechsler Intelligence Scale for Children; and (iii) mental performance to visual stimuli (GO/NO GO task). PS supplementation resulted in significant improvements in: (i) ADHD (P < 0.01), AD (P < 0.01) and HD (P < 0.01); (ii) short-term auditory memory (P < 0.05); and (iii) inattention (differentiation and reverse differentiation, P < 0.05) and inattention and impulsivity (P < 0.05). No significant differences were observed in other measurements and in the placebo group. PS was well-tolerated and showed no adverse effects. PS significantly improved ADHD symptoms and short-term auditory memory in children. PS supplementation might be a safe and natural nutritional strategy for improving mental performance in young children suffering from ADHD. © 2013 The Authors Journal of Human Nutrition and Dietetics © 2013 The British Dietetic Association Ltd.

Characterization of Dye-decolorizing Peroxidase (DyP) from Thermomonospora curvata Reveals Unique Catalytic Properties of A-type DyPs*

PubMed Central

Chen, Chao; Shrestha, Ruben; Jia, Kaimin; Gao, Philip F.; Geisbrecht, Brian V.; Bossmann, Stefan H.; Shi, Jishu; Li, Ping

2015-01-01

Dye-decolorizing peroxidases (DyPs) comprise a new family of heme peroxidases, which has received much attention due to their potential applications in lignin degradation. A new DyP from Thermomonospora curvata (TcDyP) was identified and characterized. Unlike other A-type enzymes, TcDyP is highly active toward a wide range of substrates including model lignin compounds, in which the catalytic efficiency with ABTS (kcatapp/Kmapp = (1.7 × 107) m−1 s−1) is close to that of fungal DyPs. Stopped-flow spectroscopy was employed to elucidate the transient intermediates as well as the catalytic cycle involving wild-type (wt) and mutant TcDyPs. Although residues Asp220 and Arg327 are found necessary for compound I formation, His312 is proposed to play roles in compound II reduction. Transient kinetics of hydroquinone (HQ) oxidation by wt-TcDyP showed that conversion of the compound II to resting state is a rate-limiting step, which will explain the contradictory observation made with the aspartate mutants of A-type DyPs. Moreover, replacement of His312 and Arg327 has significant effects on the oligomerization and redox potential (E°′) of the enzyme. Both mutants were found to promote the formation of dimeric state and to shift E°′ to a more negative potential. Not only do these results reveal the unique catalytic property of the A-type DyPs, but they will also facilitate the development of these enzymes as lignin degraders. PMID:26205819

Variation in host specificity and gene content in strains from genetically isolated lineages of the ectomycorrhizal fungus Paxillus involutus s. lat.

PubMed

Hedh, Jenny; Johansson, Tomas; Tunlid, Anders

2009-10-01

Ectomycorrhizal fungi are known to vary in host range. Some fungi can enter into symbiosis with multiple plant species, while others have restricted host ranges. The aim of this study was to examine variation in host specificity among strains from the basidiomycete Paxillus involutus s. lat. Recent studies have shown that this fungus consists of at least four genetically isolated lineages, phylogenetic species (PS) I (which corresponds to the morphological species Paxillus obscurosporus), PS II (P. involutus s. str.), PS III (Paxillus validus), and PS IV (not yet supported by any reference material). Thirty-five Paxillus strains of PS I to IV were examined in microcosms for their capacity to infect birch (Betula pendula) and spruce (Picea abies). Seventeen strains were compatible and formed mycorrhizae with both tree species. Seven strains were incompatible with both birch and spruce. The gene content in three pairs of incompatible and compatible strains PS I, II, and III were compared using microarray-based comparative genomic hybridizations. Of 4,113 P. involutus gene representatives analyzed, 390 varied in copy numbers in at least one of the three pairwise comparisons. Only three reporters showed significant changes in all three pairwise comparisons, and none of these were changed in a similar way in three comparisons. Our data indicate that changes in host range have occurred frequently and independently among strains in P. obscurosporus, P. involutus s. str., and P. validus. No evidence was obtained demonstrating that these changes have been associated with the gain or loss of similar genes in these three species.

Voltammetric studies of hemoglobin-coated polystyrene latex bead films on pyrolytic graphite electrodes.

PubMed

Sun, Hong; Hu, Naifei

2004-08-01

A novel hemoglobin (Hb)-coated polystyrene (PS) latex bead film was deposited on pyrolytic graphite (PG) electrode surface. In the first step, positively charged Hb molecules in pH 5.0 buffers were adsorbed on the surface of negatively charged, 500 nm diameter PS latex beads bearing sulfate groups by electrostatic interaction. The aqueous dispersion of Hb-coated PS particles was then deposited on the surface of PG electrodes and, after evaporation of the solvent, Hb-PS films were formed. The Hb-PS film electrodes exhibited a pair of well-defined, quasi-reversible cyclic voltammetric (CV) peaks at about -0.36 V vs. SCE in pH 7.0 buffers, characteristic of Hb heme Fe(III)/Fe(II) redox couples. Positions of Soret absorption band of Hb-PS films suggest that Hb retains its near-native structure in the films in its dry form and in solution at medium pH. The Hb in PS films was also acted as a catalyst to catalyze electrochemical reduction of various substrates such as trichloroacetic acid (TCA), nitrite, oxygen and hydrogen peroxide.

Third-order nonlinear optical properties of ADP crystal

NASA Astrophysics Data System (ADS)

Wang, Mengxia; Wang, Zhengping; Chai, Xiangxu; Sun, Yuxiang; Sui, Tingting; Sun, Xun; Xu, Xinguang

2018-05-01

By using the Z-scan method, we investigated the third-order nonlinear optical (NLO) properties of ADP crystal at different wavelengths (355, 532, and 1064 nm) and different orientations ([001], [100], [110], I and II). The experimental data were fitted by NLO theory, to give out the two photon absorption (TPA) coefficient β 2 and the nonlinear refractive index n 2. When the light source changed from a 40 ps, 1064 nm fundamental laser to a 30 ps, 355 nm third-harmonic-generation (THG) laser, the β 2 value increased about 5 times (0.2 × 10‑2 → 1 × 10‑2 cm GW‑1), and the n 2 value increased about 1.5 times (1.5 × 10‑16 → 2.2 × 10‑16 cm2 W‑1). Among all of the orientations, the [110] sample exhibits the smallest β 2, and the second smallest n 2. It indicates that this orientation and its surroundings will be the preferred directions for high-power laser applications of ADP crystal.

A new type of subchloroplast fragments isolated from pea chloroplasts in the presence of digitonin.

PubMed

Kochubey, S M; Bondarenko, O Yu; Shevchenko, V V

2007-09-01

Heavy fragments were isolated from pea chloroplasts using digitonin treatment and differential centrifugation. The particles were characterized by a significantly lowered chlorophyll a/b ratio, contents of photosystem I (PS I) proteins and ATPase, as well as of amount of P700. The content of photosystem II (PS II) proteins decreased insignificantly, whereas that of proteins of the light-harvesting complex II did not change. The absorption and low-temperature fluorescence spectra were indicative of a decreased content of PS I. Electron microscopy of ultrathin sections of heavy fragment preparations identified them as grana with reduced content of thylakoids. The diameter of these particles was practically the same as within chloroplasts. Comparison of various characteristics of the fragments and chloroplasts from which the fragments were isolated allowed us to define a high degree of preservation of marginal regions in thylakoids present in the heavy fragment particles. Analysis of the results shows that the procedure of fragmentation produces grana with high extent of thylakoid integrity. The phenomenon of reduction of the thylakoid content in grana, occurring as our heavy fragments, is considered in the frame of our previous hypothesis concerning the peculiarities of grana organization in the transversal direction.

The detection of interstellar C I in the immediate vicinity of the sun

NASA Technical Reports Server (NTRS)

Bruhweiler, F. C.; Kondo, Y.

1982-01-01

Multiple stacked IUE spectra reveal the presence of interstellar C I 1657 in the trough of a corresponding photospheric feature in the nearby star, Alpha PsA (d = 7 pc). This represents the first detection of this neutral atom in the interstellar medium within the immediate vicinity of the sun. It is suggested that C I may be a much better diagnostic tool in studying the local interstellar medium than the neutral species K I and Na I, which are observable at visual wavelengths. Variations in C I column density, coupled with b-values deduced from the Mg II doublet ratio, may prove to be an important means to unravel density and temperature fluctuations in the very local interstellar medium. Comparison of the line of sight toward Alpha PsA with previous Copernicus interstellar Mg II results for that of Alpha Leo tentatively indicates that the distribution of Mg II in the local cloud is not homogeneous about the sun. Rough constraints on the ionization fraction of hydrogen toward Alpha PsA do not conflict with previous data, implying that the very local interstellar medium is significantly ionized.

PS II model based analysis of transient fluorescence yield measured on whole leaves of Arabidopsis thaliana after excitation with light flashes of different energies.

PubMed

Belyaeva, N E; Schmitt, F-J; Paschenko, V Z; Riznichenko, G Yu; Rubin, A B; Renger, G

2011-02-01

Our recently presented PS II model (Belyaeva et al., 2008) was improved in order to permit a consistent simulation of Single Flash Induced Transient Fluorescence Yield (SFITFY) traces that were earlier measured by Steffen et al. (2005) on whole leaves of Arabidopsis (A.) thaliana at four different energies of the actinic flash. As the essential modification, the shape of the actinic flash was explicitly taken into account assuming that an exponentially decaying rate simulates the time dependent excitation of PS II by the 10 ns actinic flash. The maximum amplitude of this excitation exceeds that of the measuring light by 9 orders of magnitude. A very good fit of the SFITFY data was achieved in the time domain from 100 ns to 10s for all actinic flash energies (the maximum energy of 7.5 × 10¹⁶ photons/(cm²flash) is set to 100%, the relative energies of weaker actinic flashes were of ∼8%, 4%, ∼1%). Our model allows the calculation and visualization of the transient PS II redox state populations ranging from the dark adapted state, via excitation energy and electron transfer steps induced by pulse excitation, followed by final relaxation into the stationary state eventually attained under the measuring light. It turned out that the rate constants of electron transfer steps are invariant to intensity of the actinic laser flash. In marked contrast, an increase of the actinic flash energy by more than two orders of magnitude from 5.4×10¹⁴ photons/(cm²flash) to 7.5×10¹⁶ photons/(cm²flash), leads to an increase of the extent of fluorescence quenching due to carotenoid triplet (³Car) formation by a factor of 14 and of the recombination reaction between reduced primary pheophytin (Phe(-)) and P680(+) by a factor of 3 while the heat dissipation in the antenna complex remains virtually constant. The modified PS II model offers new opportunities to compare electron transfer and dissipative parameters for different species (e.g. for the green algae and the higher plant) under varying illumination conditions. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Role of clinician's experience and implant design on implant stability. An ex vivo study in artificial soft bones.

PubMed

Romanos, Georgios E; Basha-Hijazi, Abdulaziz; Gupta, Bhumija; Ren, Yan-Fang; Malmstrom, Hans

2014-04-01

Clinical experience in implant placement is important in order to prevent implant failures. However, the implant design affects the primary implant stability (PS) especially in poor quality bones. Therefore, the aim of this study was to compare the effect of clinician surgical experience on PS, when placing different type of implant designs. A total of 180 implants (90 parallel walled-P and 90 tapered-T) were placed in freshly slaughtered cow ribs. Bone quality was evaluated by two examiners during surgery and considered as 'type IV' bone. Implants (ø 5 mm, length: 15 mm, Osseotite, BIOMET 3i, Palm Beach Gardens, FL, USA) were placed by three different clinicians (master/I, good/II, non-experienced/III, under direct supervision of a manufacturer representative; 30 implants/group). An independent observer assessed the accuracy of placement by resonance frequency analysis (RFA) with implant stability quotient (ISQ) values. Two-way analysis of variance (ANOVA) and Tukey's post hoc test were used to detect the surgical experience of the clinicians and their interaction and effects of implant design on the PS. All implants were mechanically stable. The mean ISQ values were: 49.57(± 18.49) for the P-implants and 67.07(± 8.79) for the T-implants. The two-way ANOVA showed significant effects of implant design (p < .0001), clinician (p < .0001), and their interaction (p < .0001). The Tukey's multiple comparison test showed significant differences in RFA for the clinician group I/II (p = .015) and highly significant (p < .0001) between I/III and II/III. The P-implants presented (for I, II, and III) mean ISQ values 31.25/49.18/68.17 and the T-implants showed higher ISQ values, 70.15/62.08/68.98, respectively. Clinicians I and II did not show extreme differences for T-implants (p = .016). In contrast, clinician III achieved high ISQ values using P- and T-implants following the exact surgical protocol based on the manufacturer guidelines. T-implants provided high stability for experienced clinicians compared with P-implants. T-implants achieved greater PS than the P-implants. All clinicians consistently achieved PS; however, experienced clinicians achieved higher ISQ values with T-implants in poor quality bone. © 2012 Wiley Periodicals, Inc.

Measurement of tritium with high efficiency by using liquid scintillation counter with plastic scintillator.

PubMed

Furuta, Etsuko; Ohyama, Ryu-ichiro; Yokota, Shigeaki; Nakajo, Toshiya; Yamada, Yuka; Kawano, Takao; Uda, Tatsuhiko; Watanabe, Yasuo

2014-11-01

The detection efficiencies of tritium samples by using liquid scintillation counter with hydrophilic plastic scintillator (PS) was approximately 48% when the sample of 20 μL was held between 2 PS sheets treated by plasma. The activity and count rates showed a good relationship between 400 Bq to 410 KBq mL(-1). The calculated detection limit of 2 min measurement by the PS was 13 Bq mL(-1) when a confidence was 95%. The plasma method for PS produces no radioactive waste. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structure of photosystem II and substrate binding at room temperature

PubMed Central

Gul, Sheraz; Fuller, Franklin; Koroidov, Sergey; Brewster, Aaron S.; Tran, Rosalie; Alonso-Mori, Roberto; Kroll, Thomas; Michels-Clark, Tara; Laksmono, Hartawan; Sierra, Raymond G.; Stan, Claudiu A.; Hussein, Rana; Zhang, Miao; Douthit, Lacey; Kubin, Markus; de Lichtenberg, Casper; Long Vo, Pham; Nilsson, Håkan; Cheah, Mun Hon; Shevela, Dmitriy; Saracini, Claudio; Bean, Mackenzie A.; Seuffert, Ina; Sokaras, Dimosthenis; Weng, Tsu-Chien; Pastor, Ernest; Weninger, Clemens; Fransson, Thomas; Lassalle, Louise; Bräuer, Philipp; Aller, Pierre; Docker, Peter T.; Andi, Babak; Orville, Allen M.; Glownia, James M.; Nelson, Silke; Sikorski, Marcin; Zhu, Diling; Hunter, Mark S.; Lane, Thomas J.; Aquila, Andy; Koglin, Jason E.; Robinson, Joseph; Liang, Mengning; Boutet, Sébastien; Lyubimov, Artem Y.; Uervirojnangkoorn, Monarin; Moriarty, Nigel W.; Liebschner, Dorothee; Afonine, Pavel V.; Waterman, David G.; Evans, Gwyndaf; Wernet, Philippe; Dobbek, Holger; Weis, William I.; Brunger, Axel T.; Zwart, Petrus H.; Adams, Paul D.; Zouni, Athina; Messinger, Johannes; Bergmann, Uwe; Sauter, Nicholas K.; Kern, Jan; Yachandra, Vittal K.; Yano, Junko

2016-01-01

Light-induced oxidation of water by photosystem II (PS II) in plants, algae and cyanobacteria has generated most of the dioxygen in the atmosphere. PS II, a membrane-bound multi-subunit pigment-protein complex, couples the one-electron photochemistry at the reaction center with the four-electron redox chemistry of water oxidation at the Mn4CaO5 cluster in the oxygen-evolving complex (OEC) (Fig. 1a, Extended Data Fig. 1). Under illumination, the OEC cycles through five intermediate S-states (S0 to S4)1, where S1 is the dark stable state and S3 is the last semi-stable state before O-O bond formation and O2 evolution2,3. A detailed understanding of the O-O bond formation mechanism remains a challenge, and elucidating the structures of the OEC in the different S-states, as well as the binding of the two substrate waters to the catalytic site4-6, is a prerequisite for this purpose. Here we report the use of femtosecond pulses from an X-ray free electron laser (XFEL) to obtain damage free, room temperature (RT) structures of dark-adapted (S1), two-flash illuminated (2F; S3-enriched), and ammonia-bound two-flash illuminated (2F-NH3; S3-enriched) PS II. Although the recent 1.95 Å structure of PS II7 at cryogenic temperature using an XFEL provided a damage-free view of the S1 state, RT measurements are required to study the structural landscape of proteins under functional conditions8,9, and also for in situ advancement of the S-states. To investigate the water-binding site(s), ammonia, a water analog, has been used as a marker, as it binds to the Mn4CaO5 cluster in the S2 and S3 states10. Since the ammonia-bound OEC is active, the ammonia-binding Mn site is not a substrate water site10-13. Thus, this approach, together with a comparison of the native dark and 2F states, is used to discriminate between proposed O-O bond formation mechanisms. PMID:27871088

N-terminal lipid modification is required for the stable accumulation of CyanoQ in Synechocystis sp. PCC 6803

DOE PAGES

Juneau, Andrea D.; Frankel, Laurie K.; Bricker, Terry M.; ...

2016-09-22

Here, the CyanoQ protein has been demonstrated to be a component of cyanobacterial Photosystem II (PS II), but there exist a number of outstanding questions concerning its physical association with the complex. CyanoQ is a lipoprotein; upon cleavage of its transit peptide by Signal Peptidase II, which targets delivery of the mature protein to the thylakoid lumenal space, the N-terminal cysteinyl residue is lipid-modified. This modification appears to tether this otherwise soluble component to the thylakoid membrane. To probe the functional significance of the lipid anchor, mutants of the CyanoQ protein have been generated in Synechocystis sp. PCC 6803 tomore » eliminate the N-terminal cysteinyl residue, preventing lipid modification. Substitution of the N-terminal cysteinyl residue with serine (Q-C22S) resulted in a decrease in the amount of detectable CyanoQ protein to 17% that of the wild-type protein. Moreover, the physical properties of the accumulated Q-C22S protein were consistent with altered processing of the CyanoQ precursor. The Q-C22S protein was shifted to a higher apparent molecular mass and partitioned in the hydrophobic phase in TX-114 phase-partitioning experiments. These results suggest that the hydrophobic N-terminal 22 amino acids were not properly cleaved by a signal peptidase. Substitution of the entire CyanoQ transit peptide with the transit peptide of the soluble lumenal protein PsbO yielded the Q-SS mutant and resulted in no detectable accumulation of the modified CyanoQ protein. Finally, the CyanoQ protein was present at normal amounts in the PS II mutant strains ΔpsbB and ΔpsbO, indicating that an association with PS II was not a prerequisite for stable CyanoQ accumulation. Together these results indicate that CyanoQ accumulation in Synechocystis sp. PCC 6803 depends on the presence of the N-terminal lipid anchor, but not on the association of CyanoQ with the PS II complex.« less

N-terminal lipid modification is required for the stable accumulation of CyanoQ in Synechocystis sp. PCC 6803

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

Juneau, Andrea D.; Frankel, Laurie K.; Bricker, Terry M.

Here, the CyanoQ protein has been demonstrated to be a component of cyanobacterial Photosystem II (PS II), but there exist a number of outstanding questions concerning its physical association with the complex. CyanoQ is a lipoprotein; upon cleavage of its transit peptide by Signal Peptidase II, which targets delivery of the mature protein to the thylakoid lumenal space, the N-terminal cysteinyl residue is lipid-modified. This modification appears to tether this otherwise soluble component to the thylakoid membrane. To probe the functional significance of the lipid anchor, mutants of the CyanoQ protein have been generated in Synechocystis sp. PCC 6803 tomore » eliminate the N-terminal cysteinyl residue, preventing lipid modification. Substitution of the N-terminal cysteinyl residue with serine (Q-C22S) resulted in a decrease in the amount of detectable CyanoQ protein to 17% that of the wild-type protein. Moreover, the physical properties of the accumulated Q-C22S protein were consistent with altered processing of the CyanoQ precursor. The Q-C22S protein was shifted to a higher apparent molecular mass and partitioned in the hydrophobic phase in TX-114 phase-partitioning experiments. These results suggest that the hydrophobic N-terminal 22 amino acids were not properly cleaved by a signal peptidase. Substitution of the entire CyanoQ transit peptide with the transit peptide of the soluble lumenal protein PsbO yielded the Q-SS mutant and resulted in no detectable accumulation of the modified CyanoQ protein. Finally, the CyanoQ protein was present at normal amounts in the PS II mutant strains ΔpsbB and ΔpsbO, indicating that an association with PS II was not a prerequisite for stable CyanoQ accumulation. Together these results indicate that CyanoQ accumulation in Synechocystis sp. PCC 6803 depends on the presence of the N-terminal lipid anchor, but not on the association of CyanoQ with the PS II complex.« less

What spectroscopy reveals concerning the Mn oxidation levels in the oxygen evolving complex of photosystem II: X-ray to near infra-red.

PubMed

Pace, Ron J; Jin, Lu; Stranger, Rob

2012-08-28

Photosystem II (PS II), found in oxygenic photosynthetic organisms, catalyses the most energetically demanding reaction in nature, the oxidation of water to molecular oxygen and protons. The water oxidase in PS II contains a Mn(4)Ca cluster (oxygen evolving complex, OEC), whose catalytic mechanism has been extensively investigated but is still unresolved. In particular the precise Mn oxidation levels through which the cluster cycles during functional turnover are still contentious. In this, the first of several planned parts, we examine a broad range of published data relating to this question, while considering the recent atomic resolution PS II crystal structure of Umena et al. (Nature, 2011, 473, 55). Results from X-ray, UV-Vis and NIR spectroscopies are considered, using an approach that is mainly empirical, by comparison with published data from known model systems, but with some reliance on computational or other theoretical considerations. The intention is to survey the extent to which these data yield a consistent picture of the Mn oxidation states in functional PS II - in particular, to test their consistency with two current proposals for the mean redox levels of the OEC during turnover; the so called 'high' and 'low' oxidation state paradigms. These systematically differ by two oxidation equivalents throughout the redox accumulating catalytic S state cycle (states S(0)···S(3)). In summary, we find that the data, in total, substantially favor the low oxidation proposal, particularly as a result of the new analyses we present. The low oxidation state scheme is able to resolve a number of previously 'anomalous' results in the observed UV-Visible S state turnover spectral differences and in the resonant inelastic X-ray spectroscopy (RIXS) of the Mn pre-edge region of the S(1) and S(2) states. Further, the low oxidation paradigm is able to provide a 'natural' explanation for the known sensitivity of the OEC Mn cluster to cryogenic near infra-red (NIR) induced turnover to alternative spin/redox states in S(2) and S(3).

Red shift in the spectrum of a chlorophyll species is essential for the drought-induced dissipation of excess light energy in a poikilohydric moss, Bryum argenteum.

PubMed

Shibata, Yutaka; Mohamed, Ahmed; Taniyama, Koichiro; Kanatani, Kentaro; Kosugi, Makiko; Fukumura, Hiroshi

2018-05-01

Some mosses are extremely tolerant of drought stress. Their high drought tolerance relies on their ability to effectively dissipate absorbed light energy to heat under dry conditions. The energy dissipation mechanism in a drought-tolerant moss, Bryum argenteum, has been investigated using low-temperature picosecond time-resolved fluorescence spectroscopy. The results are compared between moss thalli samples harvested in Antarctica and in Japan. Both samples show almost the same quenching properties, suggesting an identical drought tolerance mechanism for the same species with two completely different habitats. A global target analysis was applied to a large set of data on the fluorescence-quenching dynamics for the 430-nm (chlorophyll-a selective) and 460-nm (chlorophyll-b and carotenoid selective) excitations in the temperature region from 5 to 77 K. This analysis strongly suggested that the quencher is formed in the major peripheral antenna of photosystem II, whose emission spectrum is significantly broadened and red-shifted in its quenched form. Two emission components at around 717 and 725 nm were assigned to photosystem I (PS I). The former component at around 717 nm is mildly quenched and probably bound to the PS I core complex, while the latter at around 725 nm is probably bound to the light-harvesting complex. The dehydration treatment caused a blue shift of the PS I emission peak via reduction of the exciton energy flow to the pigment responsible for the 725 nm band.

Immunological evaluation of polystyrene and poly(ether imide) cell culture inserts with different roughness.

PubMed

Roch, Toralf; Krüger, Anne; Kratz, Karl; Ma, Nan; Jung, Friedrich; Lendlein, Andreas

2012-01-01

For the successful clinical and biological application of polymers, their interaction with cells, tissues, and body fluids has to be well characterized. In order to investigate how the physical, chemical, and mechanical properties of candidate biomaterials influence cell behaviours, the testing sample is usually placed in commercially available cell culture plates. Thus, not only the testing sample itself but also the culture dish material might influence the cell behaviour. Therefore, an insert system was created to exclude this influence and allow investigations of the testing material solely. In this study micropatterned inserts prepared from polystyrene (PS) as well as from poly(ether imide) (PEI) with three different roughness levels of i) Rq = 0.29 μm (PS) and 0.23 μm (PEI); ii) Rq = 3.47 μm (PS) and 3.92 μm (PEI); and iii) Rq = 22.16 μm [corrected] (PS) and 22.65 μm (PEI) were explored with regard of their immuno-compatibility including the determination of potential contaminations with endotoxins or other microbial products. The endotoxin levels of the inserts were determined to be less than 0.07 EU/mL, which is well below the U.S. Food and Drug Administration limit of 0.5 EU/mL and the survival of murine macrophages cultured in the inserts was not impaired. Activation of early immune mechanisms such as complement activation and the generation of reactive oxygen species could not be observed. All tested materials had no influence on the cytokine secretion from cells of whole human blood. The investigated inserts were immuno-compatible and apparently free of contaminations with microbial products. The roughness of the inserts had no stimulatory or inhibitory effect on early immune mechanisms. Conclusively, the 24-well plate insert systems introduced in this study allow investigating the interactions of tailored surface properties such as roughness with many other cell types, without the disadvantage of the standard commercially available culture vessels influencing the biomaterial testing.

Binding of thrombin-activated platelets to a fibrin scaffold through α(IIb)β₃ evokes phosphatidylserine exposure on their cell surface.

PubMed

Brzoska, Tomasz; Suzuki, Yuko; Mogami, Hideo; Sano, Hideto; Urano, Tetsumei

2013-01-01

Recently, by employing intra-vital confocal microscopy, we demonstrated that platelets expose phosphatidylserine (PS) and fibrin accumulate only in the center of the thrombus but not in its periphery. To address the question how exposure of platelet anionic phospholipids is regulated within the thrombus, an in-vitro experiment using diluted platelet-rich plasma was employed, in which the fibrin network was formed in the presence of platelets, and PS exposure on the platelet surface was analyzed using Confocal Laser Scanning Microscopy. Almost all platelets exposed PS after treatment with tissue factor, thrombin or ionomycin. Argatroban abrogated fibrin network formation in all samples, however, platelet PS exposure was inhibited only in tissue factor- and thrombin-treated samples but not in ionomycin-treated samples. FK633, an α(IIb)β₃ antagonist, and cytochalasin B impaired platelet binding to the fibrin scaffold and significantly reduced PS exposure evoked by thrombin. Gly-Pro-Arg-Pro amide abrogated not only fibrin network formation, but also PS exposure on platelets without suppressing platelet binding to fibrin/fibrinogen. These results suggest that outside-in signals in platelets generated by their binding to the rigid fibrin network are essential for PS exposure after thrombin treatment.

Binding of Thrombin-Activated Platelets to a Fibrin Scaffold through αIIbβ3 Evokes Phosphatidylserine Exposure on Their Cell Surface

PubMed Central

Brzoska, Tomasz; Suzuki, Yuko; Mogami, Hideo; Sano, Hideto; Urano, Tetsumei

2013-01-01

Recently, by employing intra-vital confocal microscopy, we demonstrated that platelets expose phosphatidylserine (PS) and fibrin accumulate only in the center of the thrombus but not in its periphery. To address the question how exposure of platelet anionic phospholipids is regulated within the thrombus, an in-vitro experiment using diluted platelet-rich plasma was employed, in which the fibrin network was formed in the presence of platelets, and PS exposure on the platelet surface was analyzed using Confocal Laser Scanning Microscopy. Almost all platelets exposed PS after treatment with tissue factor, thrombin or ionomycin. Argatroban abrogated fibrin network formation in all samples, however, platelet PS exposure was inhibited only in tissue factor- and thrombin-treated samples but not in ionomycin-treated samples. FK633, an αIIbβ3 antagonist, and cytochalasin B impaired platelet binding to the fibrin scaffold and significantly reduced PS exposure evoked by thrombin. Gly-Pro-Arg-Pro amide abrogated not only fibrin network formation, but also PS exposure on platelets without suppressing platelet binding to fibrin/fibrinogen. These results suggest that outside-in signals in platelets generated by their binding to the rigid fibrin network are essential for PS exposure after thrombin treatment. PMID:23383331

Diffusion of liquid polystyrene into glassy poly(phenylene oxide) characterized by DSC

NASA Astrophysics Data System (ADS)

Li, Linling; Wang, Xiaoliang; Zhou, Dongshan; Xue, Gi

2013-03-01

We report a diffusion study on the polystyrene/poly(phenylene oxide) (PS/PPO) mixture consisted by the PS and PPO nanoparticles. Diffusion of liquid PS into glassy PPO (l-PS/g-PPO) is promoted by annealing the PS/PPO mixture at several temperatures below Tg of the PPO. By tracing the Tgs of the PS-rich domain behind the diffusion front using DSC, we get the relationships of PS weight fractions and diffusion front advances with the elapsed diffusion times at different diffusion temperatures using the Gordon-Taylor equation and core-shell model. We find that the plots of weight fraction of PS vs. elapsed diffusion times at different temperatures can be converted to a master curve by Time-Temperature superposition, and the shift factors obey the Arrhenius equation. Besides, the diffusion front advances of l-PS into g-PPO show an excellent agreement with the t1/2 scaling law at the beginning of the diffusion process, and the diffusion coefficients of different diffusion temperatures also obey the Arrhenius equation. We believe the diffusion mechanism for l-PS/g-PPO should be the Fickean law rather than the Case II, though there are departures of original linearity at longer diffusion times due to the limited liquid supply system. Diffusion of liquid polystyrene into glassy poly(phenylene oxide) characterized by DSC

Calcium EXAFS Establishes the Mn-Ca Cluster in the Oxygen-Evolving Complex of Photosystem II†

PubMed Central

Cinco, Roehl M.; Holman, Karen L. McFarlane; Robblee, John H.; Yano, Junko; Pizarro, Shelly A.; Bellacchio, Emanuele; Sauer, Kenneth; Yachandra, Vittal K.

2014-01-01

The proximity of Ca to the Mn cluster of the photosynthetic water-oxidation complex is demonstrated by X-ray absorption spectroscopy. We have collected EXAFS data at the Ca K-edge using active PS II membrane samples that contain approximately 2 Ca per 4 Mn. These samples are much less perturbed than previously investigated Sr-substituted samples, which were prepared subsequent to Ca depletion. The new Ca EXAFS clearly shows backscattering from Mn at 3.4 Å, a distance that agrees with that surmised from previously recorded Mn EXAFS. This result is also consistent with earlier related experiments at the Sr K-edge, using samples that contained functional Sr, that show Mn is ~ 3.5 Å distant from Sr. The totality of the evidence clearly advances the notion that the catalytic center of oxygen evolution is a Mn-Ca heteronuclear cluster. PMID:12390018

Development of slow control system for the Belle II ARICH counter

NASA Astrophysics Data System (ADS)

Yonenaga, M.; Adachi, I.; Dolenec, R.; Hataya, K.; Iori, S.; Iwata, S.; Kakuno, H.; Kataura, R.; Kawai, H.; Kindo, H.; Kobayashi, T.; Korpar, S.; Križan, P.; Kumita, T.; Mrvar, M.; Nishida, S.; Ogawa, K.; Ogawa, S.; Pestotnik, R.; Šantelj, L.; Sumiyoshi, T.; Tabata, M.; Yusa, Y.

2017-12-01

A slow control system (SCS) for the Aerogel Ring Imaging Cherenkov (ARICH) counter in the Belle II experiment was newly developed and coded in the development frameworks of the Belle II DAQ software. The ARICH is based on 420 Hybrid Avalanche Photo-Detectors (HAPDs). Each HAPD has 144 pixels to be readout and requires 6 power supply (PS) channels, therefore a total number of 2520 PS channels and 60,480 pixels have to be configured and controlled. Graphical User Interfaces (GUIs) with detector oriented view and device oriented view, were also implemented to ease the detector operation. The ARICH SCS is in operation for detector construction and cosmic rays tests. The paper describes the detailed features of the SCS and preliminary results of operation of a reduced set of hardware which confirm the scalability to the full detector.

Polystyrene plastic: a source and sink for polycyclic aromatic hydrocarbons in the marine environment

PubMed Central

Rochman, Chelsea M.; Manzano, Carlos; Hentschel, Brian T.; Massey Simonich, Staci L.; Hoh, Eunha

2014-01-01

Polycyclic aromatic hydrocarbons (PAHs) on virgin polystyrene (PS) and PS marine debris led us to examine PS as a source and sink for PAHs in the marine environment. At two locations in San Diego Bay, we measured sorption of PAHs to PS pellets, sampling at 0, 1, 3, 6, 9 and 12 months. We detected 25 PAHs using a new analytical method with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry. Several congeners were detected on samples before deployment. After deployment, some concentrations decreased (1,3-dimethylnaphthalene and 2,6-methylnaphthalene) while most increased (2-methylanthracene and all parent PAHs (PPAHs) except fluorene and fluoranthene), suggesting PS debris is a source and sink for PAHs. When comparing sorbed concentrations of PPAHs on PS to the five most common polymers (polyethylene terephthalate (PET), high-density polyethylene (HDPE), polyvinyl chloride (PVC), low-density polyethylene (LDPE), and polypropylene (PP)), PS sorbed greater concentrations than PP, PET and PVC, similar to HDPE and LDPE. Most strikingly, at 0 months, PPAHs on PS ranged from 8-200 times greater than on PET, HDPE, PVC, LDPE, and PP. The combination of greater PAHs in virgin pellets and large sorption suggests that PS may pose a greater risk of exposure to PAHs upon ingestion. PMID:24341360

Polystyrene plastic: a source and sink for polycyclic aromatic hydrocarbons in the marine environment.

PubMed

Rochman, Chelsea M; Manzano, Carlos; Hentschel, Brian T; Simonich, Staci L Massey; Hoh, Eunha

2013-12-17

Polycyclic aromatic hydrocarbons (PAHs) on virgin polystyrene (PS) and PS marine debris led us to examine PS as a source and sink for PAHs in the marine environment. At two locations in San Diego Bay, we measured sorption of PAHs to PS pellets, sampling at 0, 1, 3, 6, 9, and 12 months. We detected 25 PAHs using a new analytical method with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry. Several congeners were detected on samples before deployment. After deployment, some concentrations decreased (1,3-dimethylnaphthalene and 2,6-methylnaphthalene), while most increased [2-methylanthracene and all parent PAHs (PPAHs), except fluorene and fluoranthene], suggesting that PS debris is a source and sink for PAHs. When sorbed concentrations of PPAHs on PS are compared to the five most common polymers [polyethylene terephthalate (PET), high-density polyethylene (HDPE), polyvinyl chloride (PVC), low-density polyethylene (LDPE), and polypropylene (PP)], PS sorbed greater concentrations than PP, PET, and PVC, similar to HDPE and LDPE. Most strikingly, at 0 months, PPAHs on PS ranged from 8 to 200 times greater than on PET, HDPE, PVC, LDPE, and PP. The combination of greater PAHs in virgin pellets and large sorption suggests that PS may pose a greater risk of exposure to PAHs upon ingestion.

Changes in the energy distribution between chlorophyll-protein complexes of thylakoid membranes from pea mutants with modified pigment content. I. Changes due to the modified pigment content.

PubMed

Andreeva, Atanaska; Stoitchkova, Katerina; Busheva, Mira; Apostolova, Emilia

2003-07-01

The low-temperature (77 K) emission and excitation chlorophyll fluorescence spectra in thylakoid membranes isolated from pea mutants were investigated. The mutants have modified pigment content, structural organization, different surface electric properties and functions [Dobrikova et al., Photosynth. Res. 65 (2000) 165]. The emission spectra of thylakoid membranes were decomposed into bands belonging to the main pigment protein complexes. By an integration of the areas under them, the changes in the energy distribution between the two photosystems as well as within each one of them were estimated. It was shown that the excitation energy flow to the light harvesting, core antenna and RC complexes of photosystem II increases with the total amount of pigments in the mutants, relative to the that to photosystem I complexes. A reduction of the fluorescence ratio between aggregated trimers of LHC II and its trimeric and monomeric forms with the increase of the pigment content (chlorophyll a, chlorophyll b, and lutein) was observed. This implies that the closer packing in the complexes with a higher extent of aggregation regulates the energy distribution to the PS II core antenna and reaction centers complexes. Based on the reduced energy flow to PS II, i.e., the relative increased energy flow to PS I, we hypothesize that aggregation of LHC II switches the energy flow toward LHC I. These results suggest an additive regulatory mechanism, which redistributes the excitation energy between the two photosystems and operates at non-excess light intensities but at reduced pigment content.

High Frequency of Chronic Bacterial and Non-Inflammatory Prostatitis in Infertile Patients with Prostatitis Syndrome Plus Irritable Bowel Syndrome

PubMed Central

Vicari, Enzo; La Vignera, Sandro; Arcoria, Domenico; Condorelli, Rosita; Vicari, Lucia O.; Castiglione, Roberto; Mangiameli, Andrea; Calogero, Aldo E.

2011-01-01

Background Although prostatitis syndrome (PS) and irritable bowel syndrome (IBS) are common disorders, information on the prevalence of IBS in infertile patients with PS is relatively scanty. Therefore, this study was undertaken to estimate the frequency of PS and IBS and to evaluate the prevalence of the various diagnostic categories of prostatitis. Methodology/Principal Findings This study enrolled 152 patients with PS, diagnosed by the NIH-Chronic Prostatitis Symptom Index (NIH-CPSI) in an andrological setting, and 204 patients with IBS, diagnosed according to the Rome III diagnostic criteria in a gastroenterological setting. The patients with PS were asked to fulfill the Rome III questionnaire for IBS, whereas patients with IBS were asked to complete the NIH-CPSI. The simultaneous presence of PS and IBS was observed in 30.2% and 31.8% of the patients screened by andrologists and gastroenterologists, respectively. Altogether, 111 patients had PS plus IBS (31.2%). They had a total NIH-CPSI and pain subscale scores significantly higher than patients with PS alone. Gastrointestinal symptoms in patients with PS plus IBS were similar to those reported by patients with IBS alone and significantly greater in patients with PS alone. Patients with PS plus IBS had a significantly higher frequency of chronic bacterial prostatitis (category II) and lower of non-inflammatory prostatitis (category IIIB), compared to patients with PS alone. The frequency of inflammatory prostatitis (category IIIA) resulted similar. Conclusions/Significance Prostatitis syndromes and IBS are frequently associated in patients with PS- or IBS-related symptoms. These patients have an increased prevalence of chronic bacterial and non-inflammatory prostatitis. PMID:21494624

Cloning and characterization of a cDNA encoding topoisomerase II in pea and analysis of its expression in relation to cell proliferation.

PubMed

Reddy, M K; Nair, S; Tewari, K K; Mudgil, Y; Yadav, B S; Sopory, S K

1999-09-01

We have isolated and sequenced four overlapping cDNA clones to identify the full-length cDNA for topoisomerase II (PsTopII) from pea. Using degenerate primers, based on the conserved amino acid sequences of other eukaryotic type II topoisomerases, a 680 bp fragment was PCR-amplified with pea cDNA as template. This fragment was used as a probe to screen an oligo-dT-primed pea cDNA library. A partial cDNA clone was isolated that was truncated at the 3' end. RACE-PCR was employed to isolate the remaining portion of the gene. The total size of PsTopII is 4639 bp with an open reading frame of 4392 bp. The deduced amino acid sequence shows a strong homology to other eukaryotic topoisomerase II (topo II) at the N-terminus end. The topo II transcript was abundant in proliferative tissues. We also show that the level of topo II transcripts could be stimulated by exogenous application of growth factors that induced proliferation in vitro cultures. Light irradiation to etiolated tissue strongly stimulated the expression of topo II. These results suggest that topo II gene expression is up-regulated in response to light and hormones and correlates with cell proliferation. Besides, we have also isolated and analysed the 5'-flanking region of the pea TopII gene. This is first report on the isolation of a putative promoter for topoisomerase II from plants.

Medical risk assessment in dentistry: use of the American Society of Anesthesiologists Physical Status Classification.

PubMed

Clough, S; Shehabi, Z; Morgan, C

2016-02-12

Medical risk assessment is essential to safe patient management and the delivery of appropriate dental care. The American Society of Anesthesiologists Physical Status (ASA PS) Classification is widely used within medicine and dentistry, but has received significant criticism. This is the first UK survey to assess the consistency of medical risk assessment in dentistry. (i) To determine the use and consistency of the ASA PS among dentists and anaesthetists. (ii) To consider the appropriateness of the ASA PS in relation to dental treatment planning and delivery of care. A cross-sectional online questionnaire was distributed to anaesthetists and dental practitioners in general practice, community and hospital dental services. Questions focused on professional backgrounds, use of the ASA PS, alternative approaches to risk assessment in everyday practice and scoring of eight hypothetical patients using ASA PS. There were 101 responses, 82 were complete. Anaesthetists recorded ASA PS score more frequently than dental practitioners and found it more useful. Inconsistencies were evident in the assignment of ASA PS scores both between and within professional groups. Many dental practitioners did not use or find ASA PS helpful, with significant inconsistencies in its use. An awareness of alternative assessment scales may be useful across settings. Accepting its limitations, it would be helpful for all dentists to be educated in ASA PS and its use in medical risk assessment, particularly in relation to conscious sedation.

Localized-surface-plasmon enhanced emission from porous silicon by gold nanoparticles.

PubMed

Wang, Hui; An, Zhenghua; Ren, Qijun; Wang, Hengliang; Mao, Feilong; Chen, Zhanghai; Shen, Xuechu

2011-12-01

The porous silicon (PS) samples, decorated by Au nanoparticles (NPs) possessing localized-surface-plasmon (LSP) resonance, are prepared by the conventional anodization method. Photoluminescence (PL) is studied systematically, in particular, its dependence on the excitation power. It is found that undecorated PS samples exhibit a saturation behavior in PL intensity with increasing the pumping laser power, while the luminescence of Au-decorated PS hybrid samples have a purely linear dependence on the excitation power. In the linear response region of PS samples, addition of metal NPs layer moderately suppresses the emission while, in the saturation region, the net emission is enhanced by approximately up to 4-fold. Several possible mechanisms are discussed. We believe that the observed PL enhancement in saturation region is dominantly due to the resonant coupling between the LSP of Au NPs and the electronic excitation of PS, which inhibits the nonradiative Auger recombination process at high excitation power. These results indicate that the plasmon effect could be useful for designing even more efficient optoelectronic devices such as super bright light emitting devices and solar cells with high efficiencies. Despite many challenges, Au NPs can potentially be applied to introduce LSP resonance for the future silicon-based optoelectronics or photonics.

Influence of polarized bias and porous silicon morphology on the electrical behavior of Au-porous silicon contacts*

PubMed Central

Zhao, Yue; Li, Dong-sheng; Xing, Shou-xiang; Yang, De-ren; Jiang, Min-hua

2005-01-01

This paper reports the surface morphology and I-V curves of porous silicon (PS) samples and related devices. The observed fabrics on the PS surface were found to affect the electrical property of PS devices. When the devices were operated under different external bias (10 V or 3 V) for 10 min, their observed obvious differences in electrical properties may be due to the different control mechanisms in the Al/PS interface and PS matrix morphology. PMID:16252350

Bioactive Mushroom Polysaccharides: A Review on Monosaccharide Composition, Biosynthesis and Regulation.

PubMed

Wang, Qiong; Wang, Feng; Xu, Zhenghong; Ding, Zhongyang

2017-06-13

Mushrooms are widely distributed around the world and are heavily consumed because of their nutritional value and medicinal properties. Polysaccharides (PSs) are an important component of mushrooms, a major factor in their bioactive properties, and have been intensively studied during the past two decades. Monosaccharide composition/combinations are important determinants of PS bioactivities. This review summarizes: (i) monosaccharide composition/combinations in various mushroom PSs, and their relationships with PS bioactivities; (ii) possible biosynthetic pathways of mushroom PSs and effects of key enzymes on monosaccharide composition; (iii) regulation strategies in PS biosynthesis, and prospects for controllable biosynthesis of PSs with enhanced bioactivities.

Remote monitoring of chlorophyll fluorescence in two reef corals during the 2005 bleaching event at Lee Stocking Island, Bahamas

NASA Astrophysics Data System (ADS)

Manzello, D.; Warner, M.; Stabenau, E.; Hendee, J.; Lesser, M.; Jankulak, M.

2009-03-01

Zooxanthellae fluorescence was measured in situ, remotely, and in near real-time with a pulse amplitude modulated (PAM) fluorometer for a colony of Siderastrea siderea and Agaricia tenuifolia at Lee Stocking Island, Bahamas during the Caribbean-wide 2005 bleaching event. These colonies displayed evidence of photosystem II (PS II) inactivation coincident with thermal stress and seasonally high doses of solar radiation. Hurricane-associated declines in temperature and light appear to have facilitated the recovery of maximum quantum yield of PS II within these two colonies, although both corals responded differently to individual storms. PAM fluorometry, coupled with long-term measurement of in situ light and temperature, provides much more detail of coral photobiology on a seasonal time scale and during possible bleaching conditions than sporadic, subjective, and qualitative observations. S. siderea displayed evidence of PS II inactivation over a month prior to the issuing of a satellite-based, sea surface temperature (SST) bleaching alert by the National Oceanic and Atmospheric Administration (NOAA). In fact, recovery had already begun in S. siderea when the bleaching alert was issued. Fluorescence data for A. tenuifolia were difficult to interpret because the shaded parts of a colony were monitored and thus did not perfectly coincide with thermal stress and seasonally high doses of solar radiation as in S. siderea. These results further emphasize the limitations of solely monitoring SST (satellite or in situ) as a bleaching indicator without considering the physiological status of coral-zooxanthellae symbioses.

The Complete Light-curve Sample of Spectroscopically Confirmed SNe Ia from Pan-STARRS1 and Cosmological Constraints from the Combined Pantheon Sample

NASA Astrophysics Data System (ADS)

Scolnic, D. M.; Jones, D. O.; Rest, A.; Pan, Y. C.; Chornock, R.; Foley, R. J.; Huber, M. E.; Kessler, R.; Narayan, G.; Riess, A. G.; Rodney, S.; Berger, E.; Brout, D. J.; Challis, P. J.; Drout, M.; Finkbeiner, D.; Lunnan, R.; Kirshner, R. P.; Sanders, N. E.; Schlafly, E.; Smartt, S.; Stubbs, C. W.; Tonry, J.; Wood-Vasey, W. M.; Foley, M.; Hand, J.; Johnson, E.; Burgett, W. S.; Chambers, K. C.; Draper, P. W.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R. P.; Magnier, E. A.; Metcalfe, N.; Bresolin, F.; Gall, E.; Kotak, R.; McCrum, M.; Smith, K. W.

2018-06-01

We present optical light curves, redshifts, and classifications for 365 spectroscopically confirmed Type Ia supernovae (SNe Ia) discovered by the Pan-STARRS1 (PS1) Medium Deep Survey. We detail improvements to the PS1 SN photometry, astrometry, and calibration that reduce the systematic uncertainties in the PS1 SN Ia distances. We combine the subset of 279 PS1 SNe Ia (0.03 < z < 0.68) with useful distance estimates of SNe Ia from the Sloan Digital Sky Survey (SDSS), SNLS, and various low-z and Hubble Space Telescope samples to form the largest combined sample of SNe Ia, consisting of a total of 1048 SNe Ia in the range of 0.01 < z < 2.3, which we call the “Pantheon Sample.” When combining Planck 2015 cosmic microwave background (CMB) measurements with the Pantheon SN sample, we find {{{Ω }}}m=0.307+/- 0.012 and w=-1.026+/- 0.041 for the wCDM model. When the SN and CMB constraints are combined with constraints from BAO and local H 0 measurements, the analysis yields the most precise measurement of dark energy to date: {w}0=-1.007+/- 0.089 and {w}a=-0.222+/- 0.407 for the {w}0{w}aCDM model. Tension with a cosmological constant previously seen in an analysis of PS1 and low-z SNe has diminished after an increase of 2× in the statistics of the PS1 sample, improved calibration and photometry, and stricter light-curve quality cuts. We find that the systematic uncertainties in our measurements of dark energy are almost as large as the statistical uncertainties, primarily due to limitations of modeling the low-redshift sample. This must be addressed for future progress in using SNe Ia to measure dark energy.

A novel chromogenic medium for isolation of Pseudomonas aeruginosa from the sputa of cystic fibrosis patients.

PubMed

Laine, Larissa; Perry, John D; Lee, Jenner; Oliver, Michelle; James, Arthur L; De La Foata, Corinne; Halimi, Diane; Orenga, Sylvain; Galloway, Angela; Gould, F Kate

2009-03-01

A novel chromogenic medium for isolation and identification of Pseudomonas aeruginosa from sputa of cystic fibrosis (CF) patients was evaluated and compared with standard laboratory methods. One hundred sputum samples from distinct CF patients were cultured onto blood agar (BA), Pseudomonas CN selective agar (CN) and a Pseudomonas chromogenic medium (PS-ID). All Gram-negative morphological variants from each medium were subjected to antimicrobial susceptibility testing, and identification using a combination of biochemical and molecular methods. P. aeruginosa was isolated from 62 samples after 72 h incubation. Blood agar recovered P. aeruginosa from 56 samples (90.3%) compared with 59 samples (95.2%) using either CN or PS-ID. The positive predictive value of PS-ID (98.3%) was significantly higher than growth on CN (88.5%) for identification of P. aeruginosa (P<0.05). PS-ID is a promising medium allowing for the isolation and simultaneous identification of P. aeruginosa from sputa of CF patients.

Adaptation of the rumen microbial population to native potato starch degradation determined with the gas production technique and the nylon bag technique.

PubMed

Cone, J W; van Gelder, A H

2006-12-01

Experiments were conducted to investigate the influence of the adaptation of rumen micro-organisms on the degradation of native potato starch (PS) in the rumen. Cows were fed with rations used for gas production (GP) analysis (dry cows, 1.6% starch) and for the nylon bag (NB) technique (lactating cows, 23% starch, mainly maize starch) and a ration containing 19% native PS (lactating cows). Fermentation characteristics of 13 samples were investigated with the GP technique using rumen fluid from cows fed each of the three rations. The same samples were investigated with the NB technique in the cows obtaining the NB ration and the PS ration. The results showed that the rate of GP was influenced by the source of the rumen fluid. The fermentation rate of PS was considerably enhanced by using rumen fluid adapted to the fermentation of native PS instead of using the other rumen fluids. Incubating in cows fed the PS ration, the rate of PS degradation determined with the NB technique, was higher compared with cows fed other rations. Using the PS ration the observed lag period for PS was shorter. The results show a clear influence of ration on the degradation characteristics of starch, determined with both the GP technique and the NB technique. However, these changes in behaviour did not explain observed differences in amounts of rumen escape PS measured in vivo in animal experiments and in situ, using the NB technique.

Ferryl Protonation in Oxoiron(IV) Porphyrins and Its Role in Oxygen Transfer

DOE PAGES

Boaz, Nicholas C.; Bell, Seth R.; Groves, John T.

2015-02-04

Ferryl porphyrins, P–Fe IVmore » $=$O, are central reactive intermediates in the catalytic cycles of numerous heme proteins and a variety of model systems. There has been considerable interest in elucidating factors, such as terminal oxo basicity, that may control ferryl reactivity. Here in this study, the sulfonated, water-soluble ferryl porphyrin complexes tetramesitylporphyrin, oxoFe IVTMPS (FeTMPS-II), its 2,6-dichlorophenyl analogue, oxoFe IVTDClPS (FeTDClPS-II), and two other analogues are shown to be protonated under turnover conditions to produce the corresponding bis-aqua-iron(III) porphyrin cation radicals. The results reveal a novel internal electromeric equilibrium, P–Fe IV$=$O $$\\leftrightarrows$$ P +–Fe III(OH 2) 2. Reversible pKa values in the range of 4–6.3 have been measured for this process by pH-jump, UV–vis spectroscopy. Ferryl protonation has important ramifications for C–H bond cleavage reactions mediated by oxoiron(IV) porphyrin cation radicals in protic media. Both solvent O–H and substrate C–H deuterium kinetic isotope effects are observed for these reactions, indicating that hydrocarbon oxidation by these oxoiron(IV) porphyrin cation radicals occurs via a solvent proton-coupled hydrogen atom transfer from the substrate that has not been previously described. The effective FeO–H bond dissociation energies for FeTMPS-II and FeTDClPS-II were estimated from similar kinetic reactivities of the corresponding oxoFe IVTMPS + and oxoFe IVTDClPS + species to be ~92–94 kcal/mol. Similar values were calculated from the two-proton P +–Fe III(OH 2) 2 pK a obs and the porphyrin oxidation potentials, despite a 230 mV range for the iron porphyrins examined. Thus, the iron porphyrin with the lower ring oxidation potential has a compensating higher basicity of the ferryl oxygen. The solvent-derived proton adds significantly to the driving force for C–H bond scission.« less

Altered enzyme-linked immunosorbent assay immunoglobulin M (IgM)/IgG optical density ratios can correctly classify all primary or secondary dengue virus infections 1 day after the onset of symptoms, when all of the viruses can be isolated.

PubMed

Falconar, Andrew K I; de Plata, Elsa; Romero-Vivas, Claudia M E

2006-09-01

We compared dengue virus (DV) isolation rates and tested whether acute primary (P) and acute/probable acute secondary (S/PS) DV infections could be correctly classified serologically when the patients' first serum (S1) samples were obtained 1 to 3 days after the onset of symptoms (AOS). DV envelope/membrane protein-specific immunoglobulin M (IgM) capture and IgG capture enzyme-linked immunosorbent assay (ELISA) titrations (1/log(10) 1.7 to 1 log(10) 6.6 dilutions) were performed on 100 paired S1 and S2 samples from suspected DV infections. The serologically confirmed S/PS infections were divided into six subgroups based on their different IgM and IgG responses. Because of their much greater dynamic ranges, IgG/IgM ELISA titer ratios were more accurate and reliable than IgM/IgG optical density (OD) ratios recorded at a single cutoff dilution for discriminating between P and S/PS infections. However, 62% of these patients' S1 samples were DV IgM and IgG titer negative (or=2.60 and <2.60) discriminatory IgM/IgG OD (DOD) ratios on these S1 samples than those published previously to correctly classify the highest percentage of these P and S/PS infections. The DV isolation rate was highest (12/12; 100%) using IgG and IgM titer-negative S1 samples collected 1 day AOS, when 100% of them were correctly classified as P or S/PS infections using these higher DOD ratios.

Time Demand and Radiation Dose in 3D-Fluoroscopy-based Navigation-assisted 3D-Fluoroscopy-controlled Pedicle Screw Instrumentations.

PubMed

Balling, Horst

2018-05-01

Prospective single-center cohort study to record additional time requirements and radiation dose in navigation-assisted O-arm-controlled pedicle screw (PS) instrumentations. The aim of this study was to evaluate amount of extra-time and radiation dose for navigation-assisted PS instrumentations of the thoracolumbosacral spine using O-arm 3D-real-time-navigation (O3DN) compared to non-navigated spinal procedures (NNSPs) with a single C-arm and postoperative computed tomography (CT) scan for controlling PS positions. 3D-navigation is reported to enhance PS insertion accuracy. But time-consuming navigational steps and considerable additional radiation doses seem to limit this modern technique's attraction. A detailed analysis of additional time demand and extra-radiation dose in 3D-navigated spine surgery is not provided in literature, yet. From February 2011 through July 2015, 306 consecutive posterior instrumentations were performed in vertebral levels T10-S1 using O3DN for PS insertion. The duration of procedure-specific navigational steps of the overall collective (I) and the last cohort of 50 consecutive O3DN-surgeries (II) was compared to the average duration of analogous surgical steps in 100 consecutive NNSP using a single C-arm. 3D-radiation dose (dose-length-product, DLP) of navigational and postinstrumentation O-arm scans in group I and II was compared to the average DLP of 100 diagnostic lumbar CT scans. The average presurgical time from patient positioning on the operating table to skin incision was 46.2 ± 10.1 minutes (O3DN, I) and 40.6 ± 9.8 minutes (O3DN, II) versus 30.6 ± 8.3 minutes (NNSP) (P < 0.001, each). Intraoperative interruptions for scanning and data processing took 3.0 ± 0.6 minutes. DLPs averaged 865.1 ± 360.8 mGycm (O3DN, I) and 562.1 ± 352.6 mGycm (O3DN, II) compared to 575.5 ± 316.5 mGycm in diagnostic lumbar CT scans (P < 0.001 (I), P ≈ 0.81 [II]). After procedural experience, navigated surgeries can be performed with an additional time demand of 13.0 minutes compared to NNSP, and with a total DLP below that of a diagnostic lumbar CT scan (P ≈ 0.81). 4.

Software Reviews: Programs Worth a Second Look.

ERIC Educational Resources Information Center

Classroom Computer Learning, 1989

1989-01-01

Reviewed are three computer software programs: (1) "World GeoGraph"--geography, discovery tool, grades 6-12, Apple IIGS; (2) "Grammatik III"--language arts, grade 7-adult, IBM, PS/2, Tandy 1000; (3) "Words & Concepts I, II, III"--language and concept training for special education, age 3-9, Apple II with speech…

Measurement of tritium with plastic scintillator surface improvement with plasma treatment

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

Yoshihara, Y.; Furuta, E.; Ohyama, R.I.

2015-03-15

Tritium is usually measured by using a liquid scintillation counter. However, liquid scintillator used for measurement will become radioactive waste fluid. To solve this issue, we have developed a method of measuring tritium samples with plasma-treated plastic scintillator (PS)sheets (Plasma method). The radioactive sample is held between 2 PS sheets and the whole is enclosed in a a low-potassium glass vial. With the Plasma method of 2-min plasma treatment, we have obtained measurement efficiency of 48 ± 2 % for 2 min measurement of tritium except for tritiated water. The plasma treatment makes the PS surface rough and hydrophilic whichmore » contributes to improve the contact between tritium and PS. On the other hand, it needed almost 6 hours to obtain constant measurement efficiency. The reason was that the dry-up handling in the vial needed longer time to vaporize H{sub 2}O molecules than in the air. We tried putting silica gel beads into vials to remove H{sub 2}O molecules from PS sheet surface quickly. The silica gel beads worked well and we got constant measurement efficiency within 1-3 hours. Also, we tried using other kinds of PS treated with plasma to obtain higher measurement efficiencies of tritium samples.« less

Pelvic inflammatory disease and puerperal sepsis in Ethiopia. II. Treatment.

PubMed

Duncan, M E; Perine, P L; Krause, D W; Awoke, S; Zaidi, A A

1980-12-01

Where bacteriologic support is lacking, a combination of penicillin and streptomycin (P/S) is used empirically to treat serious gynecologic infections in Ethiopia. We compared the efficacy of P/S to a combination of penicillin and chloramphenicol (P/C) in hospitalized women who had bacteriologically confirmed pelvic inflammatory disease or puerperal sepsis (PPS). Treatment of PPS with P/C was significantly more effective in limiting the duration of fever than was treatment with P/S. Twenty-eight of 40 PPS patients had endometritis with retained products of conception that required evacuation of the uterus. The duration of fever in patients with PID who were treated with the P/C regimen was no different than that in those treated with P/S. Twenty of the 24 PID patients required surgery for drainage of abscesses, in addition to antibiotics.

Investigation on the structural characterization of pulsed p-type porous silicon

NASA Astrophysics Data System (ADS)

Wahab, N. H. Abd; Rahim, A. F. Abd; Mahmood, A.; Yusof, Y.

2017-08-01

P-type Porous silicon (PS) was sucessfully formed by using an electrochemical pulse etching (PC) and conventional direct current (DC) etching techniques. The PS was etched in the Hydrofluoric (HF) based solution at a current density of J = 10 mA/cm2 for 30 minutes from a crystalline silicon wafer with (100) orientation. For the PC process, the current was supplied through a pulse generator with 14 ms cycle time (T) with 10 ms on time (Ton) and pause time (Toff) of 4 ms respectively. FESEM, EDX, AFM, and XRD have been used to characterize the morphological properties of the PS. FESEM images showed that pulse PS (PPC) sample produces more uniform circular structures with estimated average pore sizes of 42.14 nm compared to DC porous (PDC) sample with estimated average size of 16.37nm respectively. The EDX spectrum for both samples showed higher Si content with minimal presence of oxide.

Radiation damage in a-SiO 2 exposed to intense positron pulses

NASA Astrophysics Data System (ADS)

Cassidy, D. B.; Mills, A. P.

2007-08-01

In addition to its numerous technological applications amorphous silica (a-SiO 2) is also well suited to the creation and study of exotic atoms such as positronium (Ps) and muonium. In particular, a dense Ps gas may be created by implanting an intense positron pulse into a porous a-SiO 2 sample. However, such positron pulses can constitute a significant dose of radiation, which may damage the sample. We have observed a reduction in the amount of Ps formed in a thin film of porous a-SiO 2 following irradiation by intense positron pulses, indicating the creation of paramagnetic centers. The data show that the primary effect of the irradiation is the inhibition of Ps formation, with no significant change in the subsequent Ps lifetime, from which we deduce that damage centers are created primarily in the bulk material and not on the internal surfaces of the pores, where they would be accessible to the long-lived Ps. We find that the damage is reversible, and that the system may be returned to its original state by heating to 700 K. The implications of these results for experiments with dense Ps in porous materials are discussed.

The directed differentiation of human iPS cells into kidney podocytes.

PubMed

Song, Bi; Smink, Alexandra M; Jones, Christina V; Callaghan, Judy M; Firth, Stephen D; Bernard, Claude A; Laslett, Andrew L; Kerr, Peter G; Ricardo, Sharon D

2012-01-01

The loss of glomerular podocytes is a key event in the progression of chronic kidney disease resulting in proteinuria and declining function. Podocytes are slow cycling cells that are considered terminally differentiated. Here we provide the first report of the directed differentiation of induced pluripotent stem (iPS) cells to generate kidney cells with podocyte features. The iPS-derived podocytes share a morphological phenotype analogous with cultured human podocytes. Following 10 days of directed differentiation, iPS podocytes had an up-regulated expression of mRNA and protein localization for podocyte markers including synaptopodin, nephrin and Wilm's tumour protein (WT1), combined with a down-regulation of the stem cell marker OCT3/4. In contrast to human podocytes that become quiescent in culture, iPS-derived cells maintain a proliferative capacity suggestive of a more immature phenotype. The transduction of iPS podocytes with fluorescent labeled-talin that were immunostained with podocin showed a cytoplasmic contractile response to angiotensin II (AII). A permeability assay provided functional evidence of albumin uptake in the cytoplasm of iPS podocytes comparable to human podocytes. Moreover, labeled iPS-derived podocytes were found to integrate into reaggregated metanephric kidney explants where they incorporated into developing glomeruli and co-expressed WT1. This study establishes the differentiation of iPS cells to kidney podocytes that will be useful for screening new treatments, understanding podocyte pathogenesis, and offering possibilities for regenerative medicine.

Dynamic Changes of IsiA-Containing Complexes during Long-Term Iron Deficiency in Synechocystis sp. PCC 6803.

PubMed

Ma, Fei; Zhang, Xin; Zhu, Xi; Li, Tianpei; Zhan, Jiao; Chen, Hui; He, Chenliu; Wang, Qiang

2017-01-09

Iron stress-induced protein A (IsiA), a major chlorophyll-binding protein in the thylakoid membrane, is significantly induced under iron deficiency conditions. Using immunoblot analysis and 77 K fluorescence spectroscopy combined with sucrose gradient fractionation, we monitored dynamic changes of IsiA-containing complexes in Synechocystis sp. PCC 6803 during exposure to long-term iron deficiency. Within 3 days of exposure to iron deficiency conditions, the initially induced free IsiA proteins preferentially conjugated to PS I trimer to form IsiA 18 -PS I trimers, which serve as light energy collectors for efficiently transmitting energy to PS I. With prolonged iron deficiency, IsiA proteins assembled either into IsiA aggregates or into two other types of IsiA-PS I supercomplexes, namely IsiA-PS I high fluorescence supercomplex (IHFS) and IsiA-PS I low fluorescence supercomplex (ILFS). Further analysis revealed a role for IsiA as an energy dissipater in the IHFS and as an energy collector in the ILFS. The trimeric structure of PS I mediated by PsaL was found to be indispensable for the formation of IHFS/ILFS. Dynamic changes in IsiA-containing complexes in cyanobacteria during long-term iron deficiency may represent an adaptation to iron limitation stress for flexible light energy distribution, which balances electron transfer between PS I and PS II, thus minimizing photooxidative damage. Copyright © 2017 The Author. Published by Elsevier Inc. All rights reserved.

Maternal obesity and perinatal oxidative stress: the strength of the association.

PubMed

Negro, S; Boutsikou, T; Briana, D D; Tataranno, M L; Longini, M; Proietti, F; Bazzini, F; Dani, C; Malamitsi-Puchner, A; Buonocore, G; Perrone, S

2017-01-01

Maternal obesity is a chronic inflammatory state, which has been shown to induce increased levels of free fatty acids, reactive oxygen species and inflammatory cells. Recent evidence reveals increased levels of lipid peroxidation products in the plasma of obese women during pregnancy. The aim of this study was to test the hypothesis that maternal overweight or obesity is associated with increased oxidative stress (OS) in offspring. Two hundred and forty-five pregnant women and their newborns were prospectively enrolled. Mothers were divided in two groups: lean control - LC (n=175, Group I); overweight or obese (n=70, Group II) according to BMI ≥ 25 before pregnancy. Cord blood F2-isoprostanes (F2-IsoPs), as reliable markers of OS, were measured in all newborns. Lower 1 minute APGAR score and higher weight at discharge were found in Group II neonates, compared to those of Group I (p less than 0.05). Small for gestational age (SGA) newborns of both groups showed increased levels of F2-IsoPs than appropriate (AGA) or large (LGA) for gestational age (GA) (p less than 0.01). SGA newborns of Group II had higher F2-IsoPs levels compared to SGA of Group I (p less than 0.01), which were significantly correlated to maternal BMI at the end of pregnancy (r=0.451, p less than 0.01). Multivariate regression analysis corrected for confounding factors, showed that maternal overweight or obesity was significantly associated with high F2-IsoPs levels in SGA offspring (p less than 0.01). Maternal overweight or obesity is associated with increased OS in their SGA newborns. Data suggest the need of antioxidant protection for both mothers during pregnancy and infants soon after birth.

Photosystem II functionality and antioxidant system changes during leaf rolling in post-stress emerging Ctenanthe setosa exposed to drought.

PubMed

Terzi, Rabiye; Saruhan, Neslihan; Sağlam, A; Nar, Hatice; Kadioğlu, A

2009-12-01

We studied the changes in antioxidant system and chlorophyll fluorescence parameters in post-stress emerging Ctenanthe setosa (Rosc.) Eichler (Marantaceae) plants (PSE plants) having reduced leaf area under drought stress causing leaf rolling and re-watering. PSE plants were compared to primary stressed plants (PS) in previous studies. The parameters were measured at different visual leaf rolling scores from 1 to 4 (1 is unrolled, 4 is tightly rolled and the others is intermediate form). Water potentials and stomatal conductance of leaves were gradually decreased during leaf rolling. Similarly, maximum quantum efficiency of open PS II center and quantum yield of PS II decreased during the rolling period. Non-photochemical quenching of chlorophyll fluorescence decreased at score 2 then increased while photochemical quenching did not change during leaf rolling. Electron transport rate decreased only at score 4 but approximately reached to score 1 level after re-watering. Superoxide dismutase activity was not constant at all leaf rolling scores. Ascorbate peroxidase, catalase and glutathione reductase activities generally tended to increase during leaf rolling. Lipid peroxidation and H 2 O 2 content increased at score 2 but decreased at the later scores. On the other hand, O 2 .- production increased during the rolling period. After re-watering of the plants having score 4 of leaf rolling, antioxidant enzyme activities were lower than those of score 1. Other physiological parameters also tended to reach the value of score 1. The results indicated that PSE plants gained drought tolerance by reducing leaf area effectively induced their antioxidant systems and protected the photosynthesis under drought stress similar to PS plants.

Far-red light photoacclimation (FaRLiP) in Synechococcus sp. PCC 7335. II.Characterization of phycobiliproteins produced during acclimation to far-red light.

PubMed

Ho, Ming-Yang; Gan, Fei; Shen, Gaozhong; Bryant, Donald A

2017-02-01

Phycobilisomes (PBS) are antenna complexes that harvest light for photosystem (PS) I and PS II in cyanobacteria and some algae. A process known as far-red light photoacclimation (FaRLiP) occurs when some cyanobacteria are grown in far-red light (FRL). They synthesize chlorophylls d and f and remodel PS I, PS II, and PBS using subunits paralogous to those produced in white light. The FaRLiP strain, Leptolyngbya sp. JSC-1, replaces hemidiscoidal PBS with pentacylindrical cores, which are produced when cells are grown in red or white light, with PBS with bicylindrical cores when cells are grown in FRL. This study shows that the PBS of another FaRLiP strain, Synechococcus sp. PCC 7335, are not remodeled in cells grown in FRL. Instead, cells grown in FRL produce bicylindrical cores that uniquely contain the paralogous allophycocyanin subunits encoded in the FaRLiP cluster, and these bicylindrical cores coexist with red-light-type PBS with tricylindrical cores. The bicylindrical cores have absorption maxima at 650 and 711 nm and a low-temperature fluorescence emission maximum at 730 nm. They contain ApcE2:ApcF:ApcD3:ApcD2:ApcD5:ApcB2 in the approximate ratio 2:2:4:6:12:22, and a structural model is proposed. Time course experiments showed that bicylindrical cores were detectable about 48 h after cells were transferred from RL to FRL and that synthesis of red-light-type PBS continued throughout a 21-day growth period. When considered in comparison with results for other FaRLiP cyanobacteria, the results here show that acclimation responses to FRL can differ considerably among FaRLiP cyanobacteria.

Paper sludge (PS) to bioethanol: Evaluation of virgin and recycle mill sludge for low enzyme, high-solids fermentation.

PubMed

Boshoff, Sonja; Gottumukkala, Lalitha Devi; van Rensburg, Eugéne; Görgens, Johann

2016-03-01

Paper sludge (PS) from the paper and pulp industry consists primarily of cellulose and ash and has significant potential for ethanol production. Thirty-seven PS samples from 11 South African paper and pulp mills exhibited large variation in chemical composition and resulting ethanol production. Simultaneous saccharification and fermentation (SSF) of PS in fed-batch culture was investigated at high solid loadings and low enzyme dosages. Water holding capacity and viscosity of the PS influenced ethanol production at elevated solid loadings of PS. High viscosity of PS from virgin pulp mills restricted the solid loading to 18% (w/w) at an enzyme dosage of 20 FPU/gram dry PS (gdPS), whereas an optimal solid loading of 27% (w/w) was achieved with corrugated recycle mill PS at 11 FPU/gdPS. Ethanol concentration and yield of virgin pulp and corrugated recycle PS were 34.2g/L at 66.9% and 45.5 g/L at 78.2%, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Di-n-butyl phthalate induced hypospadias relates to autophagy in genital tubercle via the PI3K/Akt/mTOR pathway.

PubMed

Li, Xiang; Li, Jinhao; Zhang, Ya; Zhou, Yun

2017-01-24

To explore the mechanisms of hypospadias induced by in utero exposure to din-butyl phthalate (DBP). Timed-pregnant Sprague-Dawley rats were administered 750 mg/kg of DBP by gavage from GD (gestation days) 13 to GD 18, whereas control group received corn oil. Genital tubercles (GTs) and blood samples were collected from male fetuses on GD 19. The serum testosterone concentration, apoptosis activity, autophagosomes and their related proteins (light chain 3 (LC3-I, LC3-II) ), and sequestosomes (SQSTM1/p62) in the GTs were then measured. Protein expression of protein kinase B (Akt), Beclin 1, phosphorylated Akt (p-Akt), p-S6, and phosphorylated mammalian target of rapamycin (p-mTOR) in the GTs were analyzed by Western blotting. The incidence of hypospadias induced by DBP was 43.64% in male fetuses. The GT volume and GT volume/body weight of fetuses were significantly reduced in the hypospadias and the non-hypospadias groups. Apoptotic cell number was significantly decreased in the GTs of the hypospadias group, but unchanged in the non-hyposadias group. The ratio of LC3-II/LC3-I was higher in the GTs from DBP exposed fetuses compared to the control group. The ratio of LC3-II/LC3-I in the GTs was higher in the hypospadias group than in the non-hypospadias group. The number of autophagosomes was increased in the GTs of the hypospadias group. Protein expression of p-S6, p-mTOR, and p-Akt were significantly decreased in the GTs of hypospadiac rats. DBP-induced hypospadias might be associated with apoptosis and autophagy mediated by the PI3K/Akt/mTOR signaling pathway in the GT.

Di-n-butyl phthalate induced hypospadias relates to autophagy in genital tubercle via the PI3K/Akt/mTOR pathway

PubMed Central

Li, Xiang; Li, Jinhao; Zhang, Ya; Zhou, Yun

2016-01-01

Objective: To explore the mechanisms of hypospadias induced by in utero exposure to din-butyl phthalate (DBP). Methods: Timed-pregnant Sprague-Dawley rats were administered 750 mg/kg of DBP by gavage from GD (gestation days) 13 to GD 18, whereas control group received corn oil. Genital tubercles (GTs) and blood samples were collected from male fetuses on GD 19. The serum testosterone concentration, apoptosis activity, autophagosomes and their related proteins (light chain 3 (LC3-I, LC3-II) ), and sequestosomes (SQSTM1/p62) in the GTs were then measured. Protein expression of protein kinase B (Akt), Beclin 1, phosphorylated Akt (p-Akt), p-S6, and phosphorylated mammalian target of rapamycin (p-mTOR) in the GTs were analyzed by Western blotting. Results: The incidence of hypospadias induced by DBP was 43.64% in male fetuses. The GT volume and GT volume/body weight of fetuses were significantly reduced in the hypospadias and the non-hypospadias groups. Apoptotic cell number was significantly decreased in the GTs of the hypospadias group, but unchanged in the non-hyposadias group. The ratio of LC3-II/LC3-I was higher in the GTs from DBP exposed fetuses compared to the control group. The ratio of LC3-II/LC3-I in the GTs was higher in the hypospadias group than in the non-hypospadias group. The number of autophagosomes was increased in the GTs of the hypospadias group. Protein expression of p-S6, p-mTOR, and p-Akt were significantly decreased in the GTs of hypospadiac rats. Conclusions: DBP-induced hypospadias might be associated with apoptosis and autophagy mediated by the PI3K/Akt/mTOR signaling pathway in the GT. PMID:27885243

Subtypes of the Type II Pit Pattern Reflect Distinct Molecular Subclasses in the Serrated Neoplastic Pathway.

PubMed

Aoki, Hironori; Yamamoto, Eiichiro; Yamano, Hiro-O; Sugai, Tamotsu; Kimura, Tomoaki; Tanaka, Yoshihito; Matsushita, Hiro-O; Yoshikawa, Kenjiro; Takagi, Ryo; Harada, Eiji; Nakaoka, Michiko; Yoshida, Yuko; Harada, Taku; Sudo, Gota; Eizuka, Makoto; Yorozu, Akira; Kitajima, Hiroshi; Niinuma, Takeshi; Kai, Masahiro; Nojima, Masanori; Suzuki, Hiromu; Nakase, Hiroshi

2018-03-15

Colorectal serrated lesions (SLs) are important premalignant lesions whose clinical and biological features are not fully understood. We aimed to establish accurate colonoscopic diagnosis and treatment of SLs through evaluation of associations among the morphological, pathological, and molecular characteristics of SLs. A total of 388 premalignant and 18 malignant colorectal lesions were studied. Using magnifying colonoscopy, microsurface structures were assessed based on Kudo's pit pattern classification system, and the Type II pit pattern was subcategorized into classical Type II, Type II-Open (Type II-O) and Type II-Long (Type II-L). BRAF/KRAS mutations and DNA methylation of CpG island methylator phenotype (CIMP) markers (MINT1, - 2, - 12, - 31, p16, and MLH1) were analyzed through pyrosequencing. Type II-O was tightly associated with sessile serrated adenoma/polyps (SSA/Ps) with BRAF mutation and CIMP-high. Most lesions with simple Type II or Type II-L were hyperplastic polyps, while mixtures of Type II or Type II-L plus more advanced pit patterns (III/IV) were characteristic of traditional serrated adenomas (TSAs). Type II-positive TSAs frequently exhibited BRAF mutation and CIMP-low, while Type II-L-positive TSAs were tightly associated with KRAS mutation and CIMP-low. Analysis of lesions containing both premalignant and cancerous components suggested Type II-L-positive TSAs may develop into KRAS-mutated/CIMP-low/microsatellite stable cancers, while Type II-O-positive SSA/Ps develop into BRAF-mutated/CIMP-high/microsatellite unstable cancers. These results suggest that Type II subtypes reflect distinct molecular subclasses in the serrated neoplasia pathway and that they could be useful hallmarks for identifying SLs at high risk of developing into CRC.

Photosensitizer adhered to cell culture microplates induces phototoxicity in carcinoma cells.

PubMed

Ziegler, Verena; Kiesslich, Tobias; Krammer, Barbara; Plaetzer, Kristjan

2013-01-01

In vitro experiments in plastic receptacles are the basis of characterization of new photosensitizers (PSs) for the photodynamic therapy. We recently reported that lipophilic PSs adhere to cell culture microplates in a kinetic-like manner (Engelhardt et al., 2011). In the current study, we examined the interaction and phototoxic effects of the microplate-adhered PS in cancer cells. Therefore, we preloaded microplates with hypericin, Foscan, PVP-hypericin, or aluminum (III) phthalocyanine tetrasulfonate chloride (AlPCS4) for 24 hours and measured the PS distribution after addition of A431 human carcinoma cells: following another 24 hours up to 68% of hypericin were detected in the cell fraction. The hydrophilic PVP-hypericin and AlPCS4 also diffused into the cells, but the quantities of PS adherence were considerably lower. Microplate-adhered Foscan appeared not to be redistributed. In contrast to the hydrophilic PSs, the cellular phototoxicity of microplate-adhered lipophilic PS was high, independent of whether the PS (i) was pre-loaded onto microplates or (ii) added simultaneously with the cells or (iii) one day after cell seeding. Based on these results, we suggest testing lipophilic PS dyes for their adherence to microplates. Furthermore, the ability of plastic materials to (reversibly) store PSs might represent a new approach for the PS delivery or the development of antimicrobial coatings.

Photosensitizer Adhered to Cell Culture Microplates Induces Phototoxicity in Carcinoma Cells

PubMed Central

Ziegler, Verena; Kiesslich, Tobias; Krammer, Barbara; Plaetzer, Kristjan

2013-01-01

In vitro experiments in plastic receptacles are the basis of characterization of new photosensitizers (PSs) for the photodynamic therapy. We recently reported that lipophilic PSs adhere to cell culture microplates in a kinetic-like manner (Engelhardt et al., 2011). In the current study, we examined the interaction and phototoxic effects of the microplate-adhered PS in cancer cells. Therefore, we preloaded microplates with hypericin, Foscan, PVP-hypericin, or aluminum (III) phthalocyanine tetrasulfonate chloride (AlPCS4) for 24 hours and measured the PS distribution after addition of A431 human carcinoma cells: following another 24 hours up to 68% of hypericin were detected in the cell fraction. The hydrophilic PVP-hypericin and AlPCS4 also diffused into the cells, but the quantities of PS adherence were considerably lower. Microplate-adhered Foscan appeared not to be redistributed. In contrast to the hydrophilic PSs, the cellular phototoxicity of microplate-adhered lipophilic PS was high, independent of whether the PS (i) was pre-loaded onto microplates or (ii) added simultaneously with the cells or (iii) one day after cell seeding. Based on these results, we suggest testing lipophilic PS dyes for their adherence to microplates. Furthermore, the ability of plastic materials to (reversibly) store PSs might represent a new approach for the PS delivery or the development of antimicrobial coatings. PMID:23509741

Development of bunch shape monitor for high-intensity beam on the China ADS proton LINAC Injector II

NASA Astrophysics Data System (ADS)

Zhu, Guangyu; Wu, Junxia; Du, Ze; Zhang, Yong; Xue, Zongheng; Xie, Hongming; Wei, Yuan; Jing, Long; Jia, Huan

2018-05-01

The development, performance, and testing of the longitudinal bunch shape monitor, namely, the Fast Faraday Cup (FFC), are presented in this paper. The FFC is an invasive instrument controlled by a stepper motor, and its principle of operation is based on a strip line structure. The longitudinal bunch shape was determined by sampling a small part of the beam hitting the strip line through a 1-mm hole. The rise time of the detector reached 24 ps. To accommodate experiments that utilize high-intensity beams, the materials of the bunch shape monitor were chosen to sustain high temperatures. Water cooling was also integrated in the detector system to enhance heat transfer and prevent thermal damage. We also present an analysis of the heating caused by the beam. The bunch shape monitor has been installed and commissioned at the China ADS proton LINAC Injector II.

Broad-spectrum Antibiotic Plus Metronidazole May Not Prevent the Deterioration of Necrotizing Enterocolitis From Stage II to III in Full-term and Near-term Infants

PubMed Central

Luo, Li-Juan; Li, Xin; Yang, Kai-Di; Lu, Jiang-Yi; Li, Lu-Quan

2015-01-01

Abstract Necrotizing enterocolitis (NEC) is the most common and frequently dangerous neonatal gastrointestinal disease. Studies have shown broad-spectrum antibiotics plus anaerobic antimicrobial therapy did not prevent the deterioration of NEC among very low birth preterm infants. However, few studies about this therapy which focused on full-term and near-term infant with NEC has been reported. The aim of this study was to evaluate the effect of broad-spectrum antibiotic plus metronidazole in preventing the deterioration of NEC from stage II to III in full-term and near-term infants. A retrospective cohort study based on the propensity score (PS) 1:1 matching was performed among the full-term and near-term infants with NEC (Bell stage ≥II). All infants who received broad-spectrum antibiotics were divided into 2 groups: group with metronidazole treatment (metronidazole was used ≥4 days continuously, 15 mg/kg/day) and group without metronidazole treatment. The depraved rates of stage II NEC between the 2 groups were compared. Meanwhile, the risk factors associated with the deterioration of stage II NEC were analyzed by case-control study in the PS-matched cases. A total of 229 infants met the inclusion criteria. Before PS-matching, we found the deterioration of NEC rate in the group with metronidazole treatment was higher than that in the group without metronidazole treatment (18.1% [28/155] vs 8.1% [6/74]; P = 0.048). After PS-matching, 73 pairs were matched, and the depraved rate of NEC in the group with metronidazole treatment was not lower than that in the group without metronidazole treatment (15.1% vs 8.2%; P = 0.2). Binary logistic regression analysis showed that sepsis after NEC (odds ratio [OR] 3.748, 95% confidence interval [CI] 1.171–11.998, P = 0.03), the need to use transfusion of blood products after diagnosis of NEC (OR 8.003, 95% CI 2.365–27.087, P = 0.00), and the need of longer time for nasogastric suction were risk factors for stage II NEC progressing to stage III (OR 1.102, 95% CI 1.004–1.21, P = 0.04). Broad-spectrum antibiotic plus metronidazole may not prevent the deterioration of NEC in full-term and near-term infants. Those infants who had sepsis required transfusion of blood products, and needed longer time for nasogastric suction after stage II NEC was more likely to progress to stage III. PMID:26496340

Molecular characterization of intestinal protozoa in two poor communities in the State of São Paulo, Brazil.

PubMed

David, Érica Boarato; Guimarães, Semíramis; de Oliveira, Ana Paula; Goulart de Oliveira-Sequeira, Teresa Cristina; Nogueira Bittencourt, Gabriela; Moraes Nardi, Ana Rita; Martins Ribolla, Paulo Eduardo; Bueno Franco, Regina Maura; Branco, Nilson; Tosini, Fabio; Bella, Antonino; Pozio, Edoardo; Cacciò, Simone M

2015-02-15

Several species of protozoa cause acute or chronic gastroenteritis in humans, worldwide. The burden of disease is particularly high among children living in developing areas of the world, where transmission is favored by lower hygienic standards and scarce availability of safe water. However, asymptomatic infection and polyparasitism are also commonly observed in poor settings. Here, we investigated the prevalence of intestinal protozoa in two small fishing villages, Porto Said (PS) and Santa Maria da Serra (SM), situated along the river Tietê in the State of São Paolo, Brazil. The villages lack basic public infrastructure and services, such as roads, public water supply, electricity and public health services. Multiple fecal samples were collected from 88 individuals in PS and from 38 individuals in SM, who were asymptomatic at the time of sampling and had no recent history of diarrheal disease. To gain insights into potential transmission routes, 49 dog fecal samples (38 from PS and 11 from SM) and 28 river water samples were also collected. All samples were tested by microscopy and PCR was used to genotype Giardia duodenalis, Blastocystis sp., Dientamoeba fragilis and Cryptosporidium spp. By molecular methods, the most common human parasite was Blastocystis sp. (prevalence, 45% in PS and 71% in SM), followed by D. fragilis (13.6% in PS, and 18.4% in SM) and G. duodenalis (18.2% in PS and 7.9% in SM); Cryptosporidium spp. were not detected. Sequence analysis revealed large genetic variation among Blastocystis samples, with subtypes (STs) 1 and 3 being predominant, and with the notable absence of ST4. Among G. duodenalis samples, assemblages A and B were detected in humans, whereas assemblages A, C and D were found in dogs. Finally, all D. fragilis samples from humans were genotype 1. A single dog was found infected with Cryptosporidium canis. River water samples were negative for the investigated parasites. This study showed a high carriage of intestinal parasites in asymptomatic individuals from two poor Brazilian villages, and highlighted a large genetic variability of Blastocystis spp. and G. duodenalis.

MUW Approach of PS OCT

NASA Astrophysics Data System (ADS)

Hitzenberger, Christoph K.; Pircher, Michael

Polarization sensitive (PS) OCT is a functional extension of OCT that exploits the light's polarization state to generate intrinsic, tissue specific contrast and enables quantitative measurements of tissue parameters. This chapter explains the technique, discusses polarization-changing light-tissue interactions and demonstrates the application of PS-OCT to retinal imaging. Two polarization-changing light-tissue interactions are discussed and their use for retinal diagnostics are demonstrated: (i) birefringence, which is found in fibrous tissues like the retinal nerve fiber layer and can be used for glaucoma diagnostics; and (ii) depolarization, which is observed in the retinal pigment epithelium (RPE) and can be used to segment the RPE and associated lesions like drusen or geographic atrophies in age related macular degeneration.

Electronic structural changes of Mn in the oxygen-evolving complex of photosystem II during the catalytic cycle.

PubMed

Glatzel, Pieter; Schroeder, Henning; Pushkar, Yulia; Boron, Thaddeus; Mukherjee, Shreya; Christou, George; Pecoraro, Vincent L; Messinger, Johannes; Yachandra, Vittal K; Bergmann, Uwe; Yano, Junko

2013-05-20

The oxygen-evolving complex (OEC) in photosystem II (PS II) was studied in the S0 through S3 states using 1s2p resonant inelastic X-ray scattering spectroscopy. The spectral changes of the OEC during the S-state transitions are subtle, indicating that the electrons are strongly delocalized throughout the cluster. The result suggests that, in addition to the Mn ions, ligands are also playing an important role in the redox reactions. A series of Mn(IV) coordination complexes were compared, particularly with the PS II S3 state spectrum to understand its oxidation state. We find strong variations of the electronic structure within the series of Mn(IV) model systems. The spectrum of the S3 state best resembles those of the Mn(IV) complexes Mn3(IV)Ca2 and saplnMn2(IV)(OH)2. The current result emphasizes that the assignment of formal oxidation states alone is not sufficient for understanding the detailed electronic structural changes that govern the catalytic reaction in the OEC.

Sulfate radical degradation of acetaminophen by novel iron-copper bimetallic oxidation catalyzed by persulfate: Mechanism and degradation pathways

NASA Astrophysics Data System (ADS)

Zhang, Yuanchun; Zhang, Qian; Hong, Junming

2017-11-01

A novel iron coupled copper oxidate (Fe2O3@Cu2O) catalyst was synthesized to activate persulfate (PS) for acetaminophen (APAP) degradation. The catalysts were characterized via field-emission scanning electron microscopy and energy-dispersive X-ray spectrometry. The effects of the catalyst, PS concentration, catalyst dosage, initial pH, dissolved oxygen were analyzed for treatment optimization. Results indicated that Fe2O3@Cu2O achieved higher efficiency in APAP degradation than Fe2O3/PS and Cu2O/PS systems. The optimal removal efficiency of APAP (90%) was achieved within 40 min with 0.6 g/L PS and 0.3 g/L catalyst. To clarify the mechanism for APAP degradation, intermediates were analyzed with gas chromatography-mass spectrometry. Three possible degradation pathways were identified. During reaction, Cu(I) was found to react with Fe(III) to generate Fe(II), which is the most active phase for PS activation. Through the use of methanol and tert-butyl alcohol (TBA) as radical trappers, SO4rad - was identified as the main radical species that is generated during oxidation.

Costing Complex Products, Operations & Support

DTIC Science & Technology

2011-10-19

last version of the Harrier II family introduced in the UK. As such it is similar to the U.S. Marine Corps’ AV-8B in basic structure , systems , and...ABSTRACT Complex products and systems (CoPS) are major capital goods in which customers play a central role from design through to disposal, such as...Complex products and systems (CoPS) are major capital goods in which customers play a central role from design through to disposal, such as large defense

Attitudes to, and experience of, pooled sampling for sexually transmitted infection testing: a web-based survey of English sexual health services.

PubMed

Shaw, Jonathan; Saunders, John Michael; Hughes, Gwenda

2018-05-01

Chlamydia trachomatis and Neisseria gonorrhoeae testing guidance recommends extragenital screening with locally validated nucleic acid amplification tests, with anatomical sites tested separately. Evidence supports multi-patient combined aliquot pooled sampling (PS) for population screening; evidence for within-patient PS is sparse. Within-patient PS could be more cost-effective for triple-site testing, but requires distinct clinical pathways and consideration over loss of information to guide risk assessments and treatment. We explored PS attitudes and practices amongst clinicians in England. A cross-sectional web-based survey was distributed to clinical leads of sexual health services throughout England in February 2016. Fifty-two (52/216, 23%) services responded. One service reported current within-patient PS and two were awaiting implementation. Of the 49 services not pooling, five were considering implementation. Concerns raised included the inability to distinguish infection site(s) (36/52, 69%), absence of national guidance (34/52, 65%) and reduced assay performance (18/52, 34%). Only 8/52 (15%) considered the current level of evidence sufficient to support PS, with 40/52 (77%) requesting further validation studies and 39/52 (77%) national guidance. PS was rarely used by respondents to this survey, although the response rate was low. The clinical challenges presented by PS need to be addressed through further development of the evidence base.

Targeting Tumor Associated Phosphatidylserine with New Zinc Dipicolylamine-Based Drug Conjugates.

PubMed

Liu, Yu-Wei; Shia, Kak-Shan; Wu, Chien-Huang; Liu, Kuan-Liang; Yeh, Yu-Cheng; Lo, Chen-Fu; Chen, Chiung-Tong; Chen, Yun-Yu; Yeh, Teng-Kuang; Chen, Wei-Han; Jan, Jiing-Jyh; Huang, Yu-Chen; Huang, Chen-Lung; Fang, Ming-Yu; Gray, Brian D; Pak, Koon Y; Hsu, Tsu-An; Huang, Kuan-Hsun; Tsou, Lun K

2017-07-19

A series of zinc(II) dipicolylamine (ZnDPA)-based drug conjugates have been synthesized to probe the potential of phosphatidylserine (PS) as a new antigen for small molecule drug conjugate (SMDC) development. Using in vitro cytotoxicity and plasma stability studies, PS-binding assay, in vivo pharmacokinetic studies, and maximum tolerated dose profiles, we provided a roadmap and the key parameters required for the development of the ZnDPA based drug conjugate. In particular, conjugate 24 induced tumor regression in the COLO 205 xenograft model and exhibited a more potent antitumor effect with a 70% reduction of cytotoxic payload compared to that of the marketed irinotecan when dosed at the same regimen. In addition to the validation of PS as an effective pharmacodelivery target for SMDC, our work also provided the foundation that, if applicable, a variety of therapeutic agents could be conjugated in the same manner to treat other PS-associated diseases.

Formate-induced inhibition of the water-oxidizing complex of photosystem II studied by EPR.

PubMed

Feyziev, Y M; Yoneda, D; Yoshii, T; Katsuta, N; Kawamori, A; Watanabe, Y

2000-04-04

The effects of various formate concentrations on both the donor and the acceptor sides in oxygen-evolving PS II membranes (BBY particles) were examined. EPR, oxygen evolution and variable chlorophyll fluorescence have been observed. It was found that formate inhibits the formation of the S(2) state multiline signal concomitant with stimulation of the Q(A)(-)Fe(2+) signal at g = 1.82. The decrease and the increase in intensities of the multiline and Q(A)(-)Fe(2+) signals, respectively, had a linear relation for formate concentrations between 5 and 500 mM. The g = 4.1 signal formation measured in the absence of methanol was not inhibited by formate up to 250 mM in the buffer. In the presence of 3% methanol the g = 4.1 signal evolved as formate concentration increased. The evolved signal could be ascribed to the inhibited centers. Oxygen evolution measured in the presence of an electron acceptor, phenyl-p-benzoquinone, was also inhibited by formate proportionally to the decrease in the multiline signal intensity. The inhibition seemed to be due to a retarded electron transfer from the water-oxidizing complex to Y(Z)(+), which was observed in the decay kinetics of the Y(Z)(+) signal induced by illumination above 250 K. These results show that formate induces inhibition of water oxidation reactions as well as electron transfer on the PS II acceptor side. The inhibition effects of formate in PS II were found to be reversible, indicating no destructive effect on the reaction center induced by formate.

Isolation Of PS II Nanoparticles And Oxygen Evolution Studies In Synechococcus Spp. PCC 7942 Under Heavy Metal Stress

NASA Astrophysics Data System (ADS)

Ahmad, Iffat Zareen; Sundaram, Shanthy; Tripathi, Ashutosh; Soumya, K. K.

2009-06-01

The effect of heavy metals was seen on the oxygen evolution pattern of a unicellular, non-heterocystous cyanobacterial strain of Synechococcus spp. PCC 7942. It was grown in a BG-11 medium supplemented with heavy metals, namely, nickel, copper, cadmium and mercury. Final concentrations of the heavy metal solution used in the culture were 0.1, 0.4 and 1 μM. All the experiments were performed in the exponential phase of the culture. Oxygen-evolving photosystem II (PS II) particles were purified from Synechococcus spp. PCC 7942 by a single-step Ni2+-affinity column chromatography after solubilization of thylakoid membranes with sucrose monolaurate. Oxygen evolution was measured with Clark type oxygen electrode fitted with a circulating water jacket. The light on the surface of the vessel was 10 w/m2. The cultures were incubated in light for 15 minutes prior to the measurement of oxygen evolution. Oxygen evolution was measured in assay mixture containing phosphate buffer (pH-7.5, 0.1 M) in the presence of potassium ferricyanide as the electron acceptor. The preparation from the control showed a high oxygen-evolving activity of 2, 300-2, 500 pmol O2 (mg Chl)-1 h-1 while the activity was decreased in the cultures grown with heavy metals. The inhibition of oxygen evolution shown by the organism in the presence of different metals was in the order Hg>Ni>Cd>Cu. Such heavy metal resistant strains will find application in the construction of PS II- based biosensors for the monitoring of pollutants.

Photosensitized H2 Production Using a Zinc Porphyrin-Substituted Protein, Platinum Nanoparticles, and Ascorbate with No Electron Relay: Participation of Good's Buffers.

PubMed

Clark, Emily R; Kurtz, Donald M

2017-04-17

Development of efficient light-driven splitting of water, 2H 2 O → 2H 2 + O 2 , often attempts to optimize photosensitization of the reductive and oxidative half-reactions individually. Numerous homogeneous and heterogeneous systems have been developed for photochemical stimulation of the reductive half reaction, 2H + + 2e - → H 2 . These systems generally consist of various combinations of a H + reduction catalyst, a photosensitizer (PS), and a "sacrificial" electron donor. Zinc(II)-porphyrins (ZnPs) have frequently been used as PSs for H 2 generation, but they are subject to various self-quenching processes in aqueous solutions. Colloidal platinum in nanoparticle form (Pt NP) is a classical H + reduction catalyst using ZnP photosensitizers, but efficient photosensitized H 2 generation requires an electron relay molecule between ZnP and Pt NP. The present report describes an aqueous system for visible (white) light-sensitized generation of H 2 using a protein-embedded Zn(II)-protoporphyrin IX as PS and Pt NP as H + reduction catalyst without an added electron relay. This system operated efficiently in piperazino- and morpholino-alkylsulfonic acid (Good's buffers), which served as sacrificial electron donors. The system also required ascorbate at relatively modest concentrations, which stabilized the Zn(II)-protoporphyrin IX against photodegradation. In the absence of an electron relay molecule, the photosensitized H 2 generation must involve formation of at least a transient complex between a protein-embedded Zn(II)-protoporphyrin IX species and Pt NP.

Groundwater Hydrology and Chemistry in and near an Emulsified Vegetable-Oil Injection Zone, Solid Waste Management Unit 17, Naval Weapons Station Charleston, North Charleston, South Carolina, 2004-2009

USGS Publications Warehouse

Vroblesky, Don A.; Petkewich, Matthew D.; Lowery, Mark A.; Conlon, Kevin J.; Casey, Clifton C.

2010-01-01

The U.S. Geological Survey and the Naval Facilities Engineering Command Southeast investigated the hydrology and groundwater chemistry in the vicinity of an emulsified vegetable-oil injection zone at Solid Waste Management Unit (SWMU) 17, Naval Weapons Station Charleston, North Charleston, South Carolina. In May 2004, Solutions-IES initiated a Phase-I pilot-scale treatability study at SWMU17 involving the injection of an edible oil emulsion into the aquifer near wells 17PS-01, 17PS-02, and 17PS-03 to treat chlorinated solvents. The Phase-I injection of emulsified vegetable oil resulted in dechlorination of trichloroethene (TCE) to cis-1,2-dichloroethene (cDCE), but the dechlorination activity appeared to stall at cDCE, with little further dechlorination of cDCE to vinyl chloride (VC) or to ethene. The purpose of the present investigation was to examine the groundwater hydrology and chemistry in and near the injection zone to gain a better understanding of the apparent remediation stall. It is unlikely that the remediation stall was due to the lack of an appropriate microbial community because groundwater samples showed the presence of Dehalococcoides species (sp.) and suitable enyzmes. The probable causes of the stall were heterogeneous distribution of the injectate and development of low-pH conditions in the injection area. Because groundwater pH values in the injection area were below the range considered optimum for dechlorination activity, a series of tests was done to examine the effect on dechlorination of increasing the pH within well 17PS-02. During and following the in-well pH-adjustment tests, VC concentrations gradually increased in some wells in the injection zone that were not part of the in-well pH-adjustment tests. These data possibly reflect a gradual microbial acclimation to the low-pH conditions produced by the injection. In contrast, a distinct increase in VC concentration was observed in well 17PS-02 following the in-well pH increase. Adjustment of the pH to near-neutral values in well 17PS-02 may have made that well relatively favorable to VC production compared with much of the rest of the injection zone, possibly accounting for acceleration of VC production at that well. Following a Phase-II injection in which Solutions-IES, Inc., injected pH-buffered emulsified vegetable oil with an improved efficiency injection approach, 1,1-dichloroethene, TCE, and cDCE rapidly decreased in concentration and are now (2009) undetectable in the injection zone, with the exception of a low concentration (43 micrograms per liter, August 2009) of cDCE in well 17PS-01. In August 2009, VC was still present in groundwater at the test wells in concentrations ranging from 150 to 640 micrograms per liter. The Phase-II injection, however, appears to have locally decreased aquifer permeability, possibly resulting in movement of contamination around, rather than through, the treatment area.

Keratins Are Altered in Intestinal Disease-Related Stress Responses.

PubMed

Helenius, Terhi O; Antman, Cecilia A; Asghar, Muhammad Nadeem; Nyström, Joel H; Toivola, Diana M

2016-09-10

Keratin (K) intermediate filaments can be divided into type I/type II proteins, which form obligate heteropolymers. Epithelial cells express type I-type II keratin pairs, and K7, K8 (type II) and K18, K19 and K20 (type I) are the primary keratins found in the single-layered intestinal epithelium. Keratins are upregulated during stress in liver, pancreas, lung, kidney and skin, however, little is known about their dynamics in the intestinal stress response. Here, keratin mRNA, protein and phosphorylation levels were studied in response to murine colonic stresses modeling human conditions, and in colorectal cancer HT29 cells. Dextran sulphate sodium (DSS)-colitis was used as a model for intestinal inflammatory stress, which elicited a strong upregulation and widened crypt distribution of K7 and K20. K8 levels were slightly downregulated in acute DSS, while stress-responsive K8 serine-74 phosphorylation (K8 pS74) was increased. By eliminating colonic microflora using antibiotics, K8 pS74 in proliferating cells was significantly increased, together with an upregulation of K8 and K19. In the aging mouse colon, most colonic keratins were upregulated. In vitro, K8, K19 and K8 pS74 levels were increased in response to lipopolysaccharide (LPS)-induced inflammation in HT29 cells. In conclusion, intestinal keratins are differentially and dynamically upregulated and post-translationally modified during stress and recovery.

Hierarchical structure of the energy landscape of proteins revisited by time series analysis. II. Investigation of explicit solvent effects

NASA Astrophysics Data System (ADS)

Alakent, Burak; Camurdan, Mehmet C.; Doruker, Pemra

2005-10-01

Time series analysis tools are employed on the principal modes obtained from the Cα trajectories from two independent molecular-dynamics simulations of α-amylase inhibitor (tendamistat). Fluctuations inside an energy minimum (intraminimum motions), transitions between minima (interminimum motions), and relaxations in different hierarchical energy levels are investigated and compared with those encountered in vacuum by using different sampling window sizes and intervals. The low-frequency low-indexed mode relationship, established in vacuum, is also encountered in water, which shows the reliability of the important dynamics information offered by principal components analysis in water. It has been shown that examining a short data collection period (100ps) may result in a high population of overdamped modes, while some of the low-frequency oscillations (<10cm-1) can be captured in water by using a longer data collection period (1200ps). Simultaneous analysis of short and long sampling window sizes gives the following picture of the effect of water on protein dynamics. Water makes the protein lose its memory: future conformations are less dependent on previous conformations due to the lowering of energy barriers in hierarchical levels of the energy landscape. In short-time dynamics (<10ps), damping factors extracted from time series model parameters are lowered. For tendamistat, the friction coefficient in the Langevin equation is found to be around 40-60cm-1 for the low-indexed modes, compatible with literature. The fact that water has increased the friction and that on the other hand has lubrication effect at first sight contradicts. However, this comes about because water enhances the transitions between minima and forces the protein to reduce its already inherent inability to maintain oscillations observed in vacuum. Some of the frequencies lower than 10cm-1 are found to be overdamped, while those higher than 20cm-1 are slightly increased. As for the long-time dynamics in water, it is found that random-walk motion is maintained for approximately 200ps (about five times of that in vacuum) in the low-indexed modes, showing the lowering of energy barriers between the higher-level minima.

An updated Type II supernova Hubble diagram

NASA Astrophysics Data System (ADS)

Gall, E. E. E.; Kotak, R.; Leibundgut, B.; Taubenberger, S.; Hillebrandt, W.; Kromer, M.; Burgett, W. S.; Chambers, K.; Flewelling, H.; Huber, M. E.; Kaiser, N.; Kudritzki, R. P.; Magnier, E. A.; Metcalfe, N.; Smith, K.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.

2018-03-01

We present photometry and spectroscopy of nine Type II-P/L supernovae (SNe) with redshifts in the 0.045 ≲ z ≲ 0.335 range, with a view to re-examining their utility as distance indicators. Specifically, we apply the expanding photosphere method (EPM) and the standardized candle method (SCM) to each target, and find that both methods yield distances that are in reasonable agreement with each other. The current record-holder for the highest-redshift spectroscopically confirmed supernova (SN) II-P is PS1-13bni (z = 0.335-0.012+0.009), and illustrates the promise of Type II SNe as cosmological tools. We updated existing EPM and SCM Hubble diagrams by adding our sample to those previously published. Within the context of Type II SN distance measuring techniques, we investigated two related questions. First, we explored the possibility of utilising spectral lines other than the traditionally used Fe IIλ5169 to infer the photospheric velocity of SN ejecta. Using local well-observed objects, we derive an epoch-dependent relation between the strong Balmer line and Fe IIλ5169 velocities that is applicable 30 to 40 days post-explosion. Motivated in part by the continuum of key observables such as rise time and decline rates exhibited from II-P to II-L SNe, we assessed the possibility of using Hubble-flow Type II-L SNe as distance indicators. These yield similar distances as the Type II-P SNe. Although these initial results are encouraging, a significantly larger sample of SNe II-L would be required to draw definitive conclusions. Tables A.1, A.3, A.5, A.7, A.9, A.11, A.13, A.15 and A.17 are also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A25

Human-induced pluripotent stem cell-derived macrophages and their immunological function in response to tuberculosis infection.

PubMed

Hong, Danping; Ding, Jiongyan; Li, Ouyang; He, Quan; Ke, Minxia; Zhu, Mengyi; Liu, Lili; Ou, Wen-Bin; He, Yulong; Wu, Yuehong

2018-02-26

Induced pluripotent stem cells (iPS) represent an innovative source for the standardized in vitro generation of macrophages (Mφ). Mφ show great promise in disease pathogenesis, particularly tuberculosis. However, there is no information about human iPS-derived (hiPS) macrophages (hiPS-Mφ) in response to tuberculosis infection. In the present study, macrophages derived from hiPS were established via embryoid body (EB) formation by using feeder-free culture conditions, and the human monocyte cell line THP-1 (THP-1-Mφ) was used as control. iPS-Mφ were characterized by using morphology, Giemsa staining, nonspecific esterase staining (α-NAE), phagocytosis, and surface phenotype. Additionally, after treatment with Bacillus Calmette-Guérin (BCG) for 24 h, cell apoptosis was detected by using an Annexin V-FITC Apoptosis Detection assay. The production of nitric oxide (NO), expression of tumor necrosis factor alpha (TNF-α), activity of apoptosis-related protein cysteine-3 (Caspase-3) and expression of B-cell lymphoma-2 (Bcl-2) were analyzed. With respect to morphology, surface phenotype, and function, the iPS-Mφ closely resembled their counterparts generated in vitro from a human monocyte cell line. iPS-Mφ exhibited the typically morphological characteristics of macrophages, such as round, oval, fusiform and irregular characteristics. The cells were Giemsa-stained-positive, α-NAE-positive, and possessed phagocytic ability. iPS-Mφ express high levels of CD14, CD11b, CD40, CD68, and major histocompatibility complex II (MHC-II). Moreover, with regard to the apoptotic rate, the production of NO, expression of TNF-α, and activity of Caspase-3 and Bcl-2, iPS-Mφ closely resemble that of their counterparts generated in vitro from human monocyte cell line in response to BCG infection. The rate of apoptosis of BCG-treated iPS-Mφ was 37.77 ± 7.94% compared to that of the untreated group at 4.97 ± 1.60% (P < 0.01) by using Annexin V-FITC Apoptosis Detection. Additionally, the rate of apoptosis of BCG-treated THP-1-Mφ was 37.1 ± 2.84% compared to that of the untreated group at 6.19 ± 1.68% (P < 0.001). The expression of TNF-α and the production of NO were significantly increased (P < 0.001), and the activity of Caspase-3 was increased. However, the expression of Bcl-2 was inhibited (P < 0.001). Our results demonstrate that Mφ derived from hiPS perform the immunological function in response to Bacillus Calmette-Guérin infection by undergoing apoptosis, increasing the production of NO and expression of TNF-α. Thus, our study may help to overcome the limitations of research into certain rare diseases due to the lack of adequate supply of disease-specific primary cells.

New psychoactive substances: Studies on the metabolism of XLR-11, AB-PINACA, FUB-PB-22, 4-methoxy-α-PVP, 25-I-NBOMe, and meclonazepam using human liver preparations in comparison to primary human hepatocytes, and human urine.

PubMed

Richter, Lilian H J; Maurer, Hans H; Meyer, Markus R

2017-10-05

New psychoactive substances (NPS) are an increasing problem in clinical and forensic toxicology. The knowledge of their metabolism is important for toxicological risk assessment and for developing toxicological urine screenings. Considering the huge numbers of NPS annually appearing on the market, metabolism studies should be realized in a fast, simple, cost efficient, and reliable way. Primary human hepatocytes (PHH) were recommended to be the gold standard for in vitro metabolism studies as they are expected to contain natural enzyme clusters, co-substrates, and drug transporters. In addition, they were already successfully used for metabolism studies of NPS. However, they also have disadvantages such as high costs and limited applicability without special equipment. The aims of the present study were therefore first to investigate exemplarily the phase I and phase II metabolism of six NPS (XLR-11, AB-PINACA, FUB-PB-22, 4-methoxy-α-PVP, 25-I-NBOMe, and meclonazepam) from different drug classes using pooled human S9 fraction (pS9) or pooled human liver microsomes combined with cytosol (pHLM/pHLC) after addition of the co-substrates for the main metabolic phase I and II reactions. Second to compare results to published data generated using primary human hepatocytes and human urine samples. Results of the incubations with pS9 or pHLM/pHLC were comparable in number and abundance of metabolites. Formation of metabolites, particularly after multi-step reactions needed a longer incubation time. However, incubations using human liver preparations resulted in a lower number of total detected metabolites compared to PHH, but they were still able to allow the identification of the main human urinary excretion products. Human liver preparations and particularly the pooled S9 fraction could be shown to be a sufficient and more cost-efficient alternative in context of metabolism studies also for developing toxicological urine screenings. It might be recommended to use the slightly cheaper pS9 fraction instead of a pHLM/pHLC combination. As formation of some metabolites needed a long incubation time, two sampling points at 60 and 360min should be recommended. Copyright © 2017 Elsevier B.V. All rights reserved.

Employment Interventions for Individuals with ASD: The Relative Efficacy of Supported Employment With or Without Prior Project SEARCH Training.

PubMed

Schall, Carol M; Wehman, Paul; Brooke, Valerie; Graham, Carolyn; McDonough, Jennifer; Brooke, Alissa; Ham, Whitney; Rounds, Rachael; Lau, Stephanie; Allen, Jaclyn

2015-12-01

This paper presents findings from a retrospective observational records review study that compares the outcomes associated with implementation of supported employment (SE) with and without prior Project SEARCH with ASD Supports (PS-ASD) on wages earned, time spent in intervention, and job retention. Results suggest that SE resulted in competitive employment for 45 adults with ASD. Twenty-five individuals received prior intervention through PS-ASD while the other 20 individuals received SE only. Individuals in this sample who received PS-ASD required fewer hours of intervention. Additionally, individuals in the PS-ASD group achieved a mean higher wage and had higher retention rates than their peers who received SE only. Further research with a larger sample is needed to confirm these findings.

Mealybug species from Chilean agricultural landscapes and main factors influencing the genetic structure of Pseudococcus viburni

PubMed Central

Correa, Margarita C. G.; Lombaert, Eric; Malausa, Thibaut; Crochard, Didier; Alvear, Andrés; Zaviezo, Tania; Palero, Ferran

2015-01-01

The present study aimed to characterize the distribution of mealybug species along Chilean agro-ecosystems and to determine the relative impact of host plant, management strategy, geography and micro-environment on shaping the distribution and genetic structure of the obscure mealybug Pseudococcus viburni. An extensive survey was completed using DNA barcoding methods to identify Chilean mealybugs to the species level. Moreover, a fine-scale study of Ps. viburni genetic diversity and population structure was carried out, genotyping 529 Ps. viburni individuals with 21 microsatellite markers. Samples from 16 localities were analyzed using Bayesian and spatially-explicit methods and the genetic dataset was confronted to host-plant, management and environmental data. Chilean crops were found to be infested by Ps. viburni, Pseudococcus meridionalis, Pseudococcus longispinus and Planococcus citri, with Ps. viburni and Ps. meridionalis showing contrasting distribution and host-plant preference patterns. Ps. viburni samples presented low genetic diversity levels but high genetic differentiation. While no significant genetic variance could be assigned to host-plant or management strategy, climate and geography were found to correlate significantly with genetic differentiation levels. The genetic characterization of Ps. viburni within Chile will contribute to future studies tracing back the origin and improving the management of this worldwide invader. PMID:26559636

Alectinib for Patients with ALK Rearrangement-Positive Non-Small Cell Lung Cancer and a Poor Performance Status (Lung Oncology Group in Kyushu 1401).

PubMed

Iwama, Eiji; Goto, Yasushi; Murakami, Haruyasu; Harada, Taishi; Tsumura, Shinsuke; Sakashita, Hiroyuki; Mori, Yoshiaki; Nakagaki, Noriaki; Fujita, Yuka; Seike, Masahiro; Bessho, Akihiro; Ono, Manabu; Okazaki, Akihito; Akamatsu, Hiroaki; Morinaga, Ryotaro; Ushijima, Shinichiro; Shimose, Takayuki; Tokunaga, Shoji; Hamada, Akinobu; Yamamoto, Nobuyuki; Nakanishi, Yoichi; Sugio, Kenji; Okamoto, Isamu

2017-07-01

Alectinib has shown marked efficacy and safety in patients with anaplastic lymphoma receptor tyrosine kinase gene (ALK) rearrangement-positive NSCLC and a good performance status (PS). It has remained unclear whether alectinib might also be beneficial for such patients with a poor PS. Eligible patients with advanced ALK rearrangement-positive NSCLC and a PS of 2 to 4 received alectinib orally at 300 mg twice daily. The primary end point of the study was objective response rate (ORR), and the most informative secondary end point was rate of PS improvement. Between September 2014 and December 2015, 18 patients were enrolled in this phase II study. Of those patients, 12, five, and one had a PS of 2, 3, or 4, respectively, whereas four patients had received prior crizotinib treatment. The ORR was 72.2% (90% confidence interval: 52.9-85.8%). The ORR did not differ significantly between patients with a PS of 2 and those with a PS of 3 or higher (58.3% and 100%, respectively [p = 0.114]). The PS improvement rate was 83.3% (90% confidence interval: 64.8-93.1%, p < 0.0001), with the frequency of improvement to a PS of 0 or 1 being 72.2%. The median progression-free survival was 10.1 months. Toxicity was mild, with the frequency of adverse events of grade 3 or higher being low. Neither dose reduction nor withdrawal of alectinib because of toxicity was necessary. Alectinib is a treatment option for patients with ALK rearrangement-positive NSCLC and a poor PS. Copyright © 2017 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

Development of tolerance of egg plant (Solanum melangena L.) to field application of dimethoate.

PubMed

Khillar, R; Acharya, S; Mohapatra, P K

2010-07-01

Dimethoate, at field concentration (1.419 mg g(-1) fr wt), caused inhibition of photosynthesis, transpiration and stomatal conductance of Solanum melangena L. on first treatment but subsequent treatments caused adaptation and recovery of these parameters. The variable fluorescence (F(v)), dissipation (DI(0)/RC), 2 ms relative variable fluorescence (V(j)), net rate of PS II closure (M(0)), and maximum trapping rate of active PS II (TR(0)/RC) increased initially but reduced to the control value with repetition of treatment. However, fluorescence yield (TR(0)/Abs), electron transport probability (ET(0)/TR(0)) and activity of RC (ET(0)/RC) increased with each treatment. With each subsequent treatment there was enhancement of activities of esterases and decrease of insecticide content of leaves.

Pearson marrow pancreas syndrome in patients suspected to have Diamond-Blackfan anemia.

PubMed

Gagne, Katelyn E; Ghazvinian, Roxanne; Yuan, Daniel; Zon, Rebecca L; Storm, Kelsie; Mazur-Popinska, Magdalena; Andolina, Laura; Bubala, Halina; Golebiowska, Sydonia; Higman, Meghan A; Kalwak, Krzysztof; Kurre, Peter; Matysiak, Michal; Niewiadomska, Edyta; Pels, Salley; Petruzzi, Mary Jane; Pobudejska-Pieniazek, Aneta; Szczepanski, Tomasz; Fleming, Mark D; Gazda, Hanna T; Agarwal, Suneet

2014-07-17

Pearson marrow pancreas syndrome (PS) is a multisystem disorder caused by mitochondrial DNA (mtDNA) deletions. Diamond-Blackfan anemia (DBA) is a congenital hypoproliferative anemia in which mutations in ribosomal protein genes and GATA1 have been implicated. Both syndromes share several features including early onset of severe anemia, variable nonhematologic manifestations, sporadic genetic occurrence, and occasional spontaneous hematologic improvement. Because of the overlapping features and relative rarity of PS, we hypothesized that some patients in whom the leading clinical diagnosis is DBA actually have PS. Here, we evaluated patient DNA samples submitted for DBA genetic studies and found that 8 (4.6%) of 173 genetically uncharacterized patients contained large mtDNA deletions. Only 2 (25%) of the patients had been diagnosed with PS on clinical grounds subsequent to sample submission. We conclude that PS can be overlooked, and that mtDNA deletion testing should be performed in the diagnostic evaluation of patients with congenital anemia. © 2014 by The American Society of Hematology.

Rapid Analysis of Bisphenol A and Its Analogues in Food Packaging Products by Paper Spray Ionization Mass Spectrometry.

PubMed

Chen, Shuo; Chang, Quanying; Yin, Kai; He, Qunying; Deng, Yongxiu; Chen, Bo; Liu, Chengbin; Wang, Ying; Wang, Liping

2017-06-14

In this study, a paper spray ionization mass spectrometric (PS-MS) method was developed for the rapid in situ screening and simultaneous quantitative analysis of bisphenol A and its analogues, i.e., bisphenol S, bisphenol F, and bisphenol AF, in food packaging products. At the optimal PS-MS conditions, the calibration curves of bisphenols in the range of 1-100 μg/mL were linear. The correlation coefficients were higher than 0.998, and the LODs of the target compounds were 0.1-0.3 μg/mL. After a simple treatment by dichloromethane on the surface, the samples were analyzed by PS-MS in situ for rapid screening without a traditional sample pretreatment procedure, such as powdering, extraction, and enrichment steps. The analytical time of the PS-MS method was less than 1 min. In comparison with conventional HPLC-MS/MS, it was demonstrated that PS-MS was a more effective high-throughput screening and quantitative analysis method.

Polysaccharides from Ganoderma formosanum function as a Th1 adjuvant and stimulate cytotoxic T cell response in vivo.

PubMed

Pi, Chia-Chen; Chu, Ching-Liang; Lu, Chu-Ying; Zhuang, Yu-Jing; Wang, Cheng-Li; Yu, Yao-Hsuan; Wang, Hui-Yi; Lin, Chih-Chung; Chen, Chun-Jen

2014-01-09

The fungus of Ganoderma is a basidiomycete that possesses a variety of pharmacological effects and has been used in traditional Asian medicine for centuries. Ganoderma formosanum is a native Ganoderma species isolated in Taiwan, and we have previously demonstrated that PS-F2, a polysaccharide fraction purified from the submerged culture broth of G. formosanum, exhibits immunostimulatory properties in macrophages. In this study, we further characterized the adjuvant functions of PS-F2. In vitro, PS-F2 stimulated dendritic cells (DCs) to produce proinflammatory cytokines, including TNF-α, interleukin (IL)-6, and IL-12/IL-23 p40. PS-F2 also stimulated DCs to express the maturation markers CD40, CD80, CD86, and MHC class II. In a murine splenocyte culture, PS-F2 treatment resulted in elevated expression of T-bet and interferon (IFN)-γ in T lymphocytes. When used as an adjuvant in vivo with the ovalbumin (OVA) antigen, PS-F2 stimulated OVA-specific antibody production and primed IFN-γ production in OVA-specific T lymphocytes. PS-F2-adjuvated immunization also induced OVA-specific CTLs, which protected mice from a challenge with tumor cells expressing OVA. Collectively, our data show that PS-F2 functions as an adjuvant capable of inducing a Th1-polarized adaptive immune response, which would be useful in vaccines against viruses and tumors. Copyright © 2013 Elsevier Ltd. All rights reserved.

Immunogenicity and safety of a new meningococcal A conjugate vaccine in Indian children aged 2-10 years: a phase II/III double-blind randomized controlled trial.

PubMed

Hirve, Siddhivinayak; Bavdekar, Ashish; Pandit, Anand; Juvekar, Sanjay; Patil, Malini; Preziosi, Marie-Pierre; Tang, Yuxiao; Marchetti, Elisa; Martellet, Lionel; Findlow, Helen; Elie, Cheryl; Parulekar, Varsha; Plikaytis, Brian; Borrow, Ray; Carlone, George; Kulkarni, Prasad S; Goel, Akshay; Suresh, Karupothula; Beri, Suresh; Kapre, Subhash; Jadhav, Suresh; Preaud, Jean-Marie; Viviani, Simonetta; LaForce, F Marc

2012-10-05

This study compares the immunogenicity and safety of a single dose of a new meningococcal A conjugate vaccine (PsA-TT, MenAfriVac™, Serum Institute of India Ltd., Pune) against the meningococcal group A component of a licensed quadrivalent meningococcal polysaccharide vaccine (PsACWY, Mencevax ACWY(®), GSK, Belgium) 28 days after vaccination in Indian children. This double-blind, randomized, controlled study included 340 Indian children aged 2-10 years enrolled from August to October 2007; 169 children received a dose of PsA-TT while 171 children received a dose of PsACWY. Intention-to-treat analysis showed that 95.2% of children in PsA-TT group had a ≥4-fold response in serum bactericidal titers (rSBA) 28 days post vaccination as compared to 78.2% in the PsACWY group. A significantly higher rSBA GMT (11,209, 95%CI 9708-12,942) was noted in the PsA-TT group when compared to PsACWY group (2838, 95%CI 2368-3401). Almost all children in both vaccine groups had a ≥4-fold response in group A-specific IgG concentration but the IgG GMC was significantly greater in the PsA-TT group (89.1 μg/ml, 95%CI 75.5-105.0) when compared to the PsACWY group (15.3 μg/ml, 95%CI 12.3-19.2). Local and systemic reactions during the 4 days after immunization were similar for both vaccine groups except for tenderness (30.2% in PsA-TT group vs 12.3% in PsACWY group). None of the adverse events or serious adverse events was related to the study vaccines. We conclude that MenAfriVac™ is well tolerated and significantly more immunogenic when compared to a licensed polysaccharide vaccine, in 2-to-10-year-old Indian children. Copyright © 2012 Elsevier Ltd. All rights reserved.

Endoscopic stenting for hilar cholangiocarcinoma: efficacy of unilateral and bilateral placement of plastic and metal stents in a retrospective review of 480 patients

PubMed Central

2012-01-01

Background Endoscopic biliary drainage of hilar cholangiocarcinoma is controversial with respect to the optimal types of stents and the extent of drainage. This study evaluated endoscopic palliation in patients with hilar cholangiocarcinoma using self-expandable metallic stents (SEMS) and plastic stents (PS).We also compared unilateral and bilateral stent placement according to the Bismuth classification. Methods Data on 480 patients receiving endoscopic biliary drainage for hilar cholangiocarcinoma between September 1995 and December 2010 were retrospectively reviewed to evaluate the following outcome parameters: technical success (TS), functional success (FS), early and late complications, stent patency and survival. Patients were followed from stent insertion until death or stent occlusion. Patients were divided into 3 groups according to the Bismuth classification (Group 1, type I; Group 2, type II; Group 3, type > III). Results The initial stent insertion was successful in 450 (93.8%) patients. TS was achieved in 204 (88.3%) patients treated with PS and in 246 (98.8%) patients palliated with SEMS (p < 0.001). In the intention-to-treat (ITT) analysis, the FS in patients treated with SEMS (97.9%) was significantly higher than in patients treated with PS (84.8%) (p < 0.001). Late complications occurred in 115 (56.4%) patients treated with PS and 60 (24.4%) patients treated with SEMS (p < 0.001). The median duration of stent patency in weeks (w) were as follows: 20 w in patients palliated with PS and 27 w in patients treated with SEMS (p < 0.0001). In Group 2, the median duration of PS patency was 17 w and 18 w for unilateral and bilateral placement, respectively (p = 0.0004); the median duration of SEMS patency was 24 w and 29 w for unilateral and bilateral placement, respectively (p < 0.0001). Multivariate analysis using the Poisson regression showed that SEMS placement (B = 0.48; P < 0.01) and bilateral deployment (B = 0.24; P < 0.01) were the only independent prognostic factors associated with stent patency. Conclusions SEMS insertion for the palliation of hilar cholangiocarcinoma offers higher technical and clinical success rates in the ITT analysis as well as lower complication rates and a superior cumulative stent patency when compared with PS placement in all Bismuth classifications. The cumulative patency of bilateral SEMS or PS stents was significantly higher than that of unilateral SEMS or PS stents, with lower occlusion rates in Bismuth II patients. PMID:22873816

Effects of aggregation of drug and diagnostic codes on the performance of the high-dimensional propensity score algorithm: an empirical example.

PubMed

Le, Hoa V; Poole, Charles; Brookhart, M Alan; Schoenbach, Victor J; Beach, Kathleen J; Layton, J Bradley; Stürmer, Til

2013-11-19

The High-Dimensional Propensity Score (hd-PS) algorithm can select and adjust for baseline confounders of treatment-outcome associations in pharmacoepidemiologic studies that use healthcare claims data. How hd-PS performance is affected by aggregating medications or medical diagnoses has not been assessed. We evaluated the effects of aggregating medications or diagnoses on hd-PS performance in an empirical example using resampled cohorts with small sample size, rare outcome incidence, or low exposure prevalence. In a cohort study comparing the risk of upper gastrointestinal complications in celecoxib or traditional NSAIDs (diclofenac, ibuprofen) initiators with rheumatoid arthritis and osteoarthritis, we (1) aggregated medications and International Classification of Diseases-9 (ICD-9) diagnoses into hierarchies of the Anatomical Therapeutic Chemical classification (ATC) and the Clinical Classification Software (CCS), respectively, and (2) sampled the full cohort using techniques validated by simulations to create 9,600 samples to compare 16 aggregation scenarios across 50% and 20% samples with varying outcome incidence and exposure prevalence. We applied hd-PS to estimate relative risks (RR) using 5 dimensions, predefined confounders, ≤ 500 hd-PS covariates, and propensity score deciles. For each scenario, we calculated: (1) the geometric mean RR; (2) the difference between the scenario mean ln(RR) and the ln(RR) from published randomized controlled trials (RCT); and (3) the proportional difference in the degree of estimated confounding between that scenario and the base scenario (no aggregation). Compared with the base scenario, aggregations of medications into ATC level 4 alone or in combination with aggregation of diagnoses into CCS level 1 improved the hd-PS confounding adjustment in most scenarios, reducing residual confounding compared with the RCT findings by up to 19%. Aggregation of codes using hierarchical coding systems may improve the performance of the hd-PS to control for confounders. The balance of advantages and disadvantages of aggregation is likely to vary across research settings.

Structural and transcription analysis of two homologous genes for the P700 chlorophyll a-apoproteins in Chlamydomonas reinhardii: evidence for in vivo trans-splicing

PubMed Central

Kück, Ulrich; Choquet, Yves; Schneider, Michel; Dron, Michel; Bennoun, Pierre

1987-01-01

The two homologous genes for the P700 chlorophyll a-apoproteins (ps1A1 and ps1A2) are encoded by the plastom in the green alga Chlamydomonas reinhardii. The structure and organization of the two genes were determined by comparison with the homologous genes from maize using data from heterologous hybridizations as well as from DNA and RNA sequencing. While the ps1A2 (736 codons) gene shows a continuous gene organization, the ps1A1 (754 codons) gene possesses some unusual features. The discontinuous gene is split into three separate exons which are scattered around the circular chloroplast genome. Exon 1 (86 bp) is separated by ∼50 kb from exon 2 (198 bp), which is located ∼ 90 kb apart from exon 3 (1984 bp). All exons are flanked by intronic sequences of group II. Transcription analysis reveals that the ps1A2 gene hybridizes with a 2.8-kb transcript, while all exon regions of the ps1A1 gene are homologous to a mature mRNA of 2.7 kb. From our data we conclude that the three distantly separated exonic sequences of the ps1A1 gene constitute a functional gene which probably operates by a trans-splicing mechanism. ImagesFig. 3.Fig. 5.Fig. 6. PMID:16453785

Using PS1 and Type Ia Supernovae To Make Most Precise Measurement of Dark Energy To Date

NASA Astrophysics Data System (ADS)

Scolnic, Daniel; Pan-STARRS

2018-01-01

I will review recent results that present optical light curves, redshifts, and classifications for 361 spectroscopically confirmed Type Ia supernovae (SNeIa) discovered by the Pan-STARRS1 (PS1) Medium Deep Survey. I will go over improvements to the PS1 SN photometry, astrometry and calibration that reduce the systematic uncertainties in the PS1 SN Ia distances. We combined distances of PS1 SNe with distance estimates of SNIa from SDSS, SNLS, various low-z and HST samples to form the largest combined sample of SN Ia consisting of a total of ~1050 SN Ia ranging from 0.01 < z < 2.3, which we call the ‘Pantheon Sample’. Photometric calibration uncertainties have long dominated the systematic error budget of every major analysis of cosmological parameters with SNIa. Using the PS1 relative calibration, we have reduced these calibration systematics to the point where they are similar in magnitude to the other major sources of known systematic uncertainties: the nature of the intrinsic scatter of SNIa and modeling of selection effects. I will present measurements of dark energy which are now the most precise measurements of dark energy to date.

Machine-learned Identification of RR Lyrae Stars from Sparse, Multi-band Data: The PS1 Sample

NASA Astrophysics Data System (ADS)

Sesar, Branimir; Hernitschek, Nina; Mitrović, Sandra; Ivezić, Željko; Rix, Hans-Walter; Cohen, Judith G.; Bernard, Edouard J.; Grebel, Eva K.; Martin, Nicolas F.; Schlafly, Edward F.; Burgett, William S.; Draper, Peter W.; Flewelling, Heather; Kaiser, Nick; Kudritzki, Rolf P.; Magnier, Eugene A.; Metcalfe, Nigel; Tonry, John L.; Waters, Christopher

2017-05-01

RR Lyrae stars may be the best practical tracers of Galactic halo (sub-)structure and kinematics. The PanSTARRS1 (PS1) 3π survey offers multi-band, multi-epoch, precise photometry across much of the sky, but a robust identification of RR Lyrae stars in this data set poses a challenge, given PS1's sparse, asynchronous multi-band light curves (≲ 12 epochs in each of five bands, taken over a 4.5 year period). We present a novel template fitting technique that uses well-defined and physically motivated multi-band light curves of RR Lyrae stars, and demonstrate that we get accurate period estimates, precise to 2 s in > 80 % of cases. We augment these light-curve fits with other features from photometric time-series and provide them to progressively more detailed machine-learned classification models. From these models, we are able to select the widest (three-fourths of the sky) and deepest (reaching 120 kpc) sample of RR Lyrae stars to date. The PS1 sample of ˜45,000 RRab stars is pure (90%) and complete (80% at 80 kpc) at high galactic latitudes. It also provides distances that are precise to 3%, measured with newly derived period-luminosity relations for optical/near-infrared PS1 bands. With the addition of proper motions from Gaia and radial velocity measurements from multi-object spectroscopic surveys, we expect the PS1 sample of RR Lyrae stars to become the premier source for studying the structure, kinematics, and the gravitational potential of the Galactic halo. The techniques presented in this study should translate well to other sparse, multi-band data sets, such as those produced by the Dark Energy Survey and the upcoming Large Synoptic Survey Telescope Galactic plane sub-survey.

Evaluating the combined effects of pretilachlor and UV-B on two Azolla species.

PubMed

Prasad, Sheo Mohan; Kumar, Sushil; Parihar, Parul; Singh, Anita; Singh, Rachana

2016-03-01

The present study assessed the comparative responses of two agronomic species of Azolla (A.microphylla and A. pinnata) exposed to man-made and natural stressors by evaluating biomass accumulation, pigments (chlorophyll a and b and carotenoid contents), photosynthetic activity and nitrogen metabolism. The study was carried out in field where two species of Azolla were cultured and treated with various concentrations (5, 10 and 20 μg ml(-1)) of herbicide; pretilachlor [2-chloro-2,6-diethyl-N-(2-propoxyethyl) acetanilide] and enhanced levels (UV-B1: ambient +2.2 kJ m(-2) day(-1) and UV-B2: ambient +4.4 kJ m(-2) day(-1)) of UV-B, alone as well as in combination. Biomass accumulation, photosynthetic pigments; chlorophyll a, b and carotenoids, photosynthetic oxygen yield and photosynthetic electron transport activities i.e. photosystem II (PS II) and photosystem I (PS I) in both the species declined with the increasing doses of pretilachlor and UV-B radiation, which further declined when applied in combination. The lower doses (5 and 10 μg ml(-1)) of pretilachlor and UV-B (UV-B1 and UV-B2) alone, damaged mainly the oxidation side of PS II, whereas higher dose (20 μg ml(-1)) of pretilachlor alone and in combination with UV-B1 and UV-B2 caused damage to PS II reaction centre and beyond this towards the reduction side. A significant enhancement in respiration was also noticed in fronds of both the Azolla species following pretilachlor and UV-B treatment, hence indicating strong damaging effect. The nitrate assimilating enzymes - nitrate reductase and nitrite reductase and ammonium assimilating enzymes - glutamine synthetase and glutamate synthase were also severely affected when treated either with pretilachlor and/or UV-B while glutamate dehydrogenase exhibited a stimulatory response. The study suggests that both the species of Azolla showed considerable damage under pretilachlor and UV-B treatments alone, however, in combination the effect was more intense. Further, in comparison to A. pinnata, A. microphylla exhibited greater resistance against tested doses of both the stresses, either alone or in combination. Copyright © 2015 Elsevier Inc. All rights reserved.

Photocatalytic activity of Cr-doped TiO2 nanoparticles deposited on porous multicrystalline silicon films

PubMed Central

2014-01-01

This work deals with the deposition of Cr-doped TiO2 thin films on porous silicon (PS) prepared from electrochemical anodization of multicrystalline (mc-Si) Si wafers. The effect of Cr doping on the properties of the TiO2-Cr/PS/Si samples has been investigated by means of X-ray diffraction (XRD), atomic force microcopy (AFM), photoluminescence, lifetime, and laser beam-induced current (LBIC) measurements. The photocatalytic activity is carried out on TiO2-Cr/PS/Si samples. It was found that the TiO2-Cr/PS/mc-Si type structure degrades an organic pollutant (amido black) under ultraviolet (UV) light. A noticeable degradation of the pollutant is obtained for a Cr doping of 2 at. %. This result is discussed in light of LBIC and photoluminescence measurements. PMID:25313302

Photocatalytic activity of Cr-doped TiO2 nanoparticles deposited on porous multicrystalline silicon films.

PubMed

Hajjaji, Anouar; Trabelsi, Khaled; Atyaoui, Atef; Gaidi, Mounir; Bousselmi, Latifa; Bessais, Brahim; El Khakani, My Ali

2014-01-01

This work deals with the deposition of Cr-doped TiO2 thin films on porous silicon (PS) prepared from electrochemical anodization of multicrystalline (mc-Si) Si wafers. The effect of Cr doping on the properties of the TiO2-Cr/PS/Si samples has been investigated by means of X-ray diffraction (XRD), atomic force microcopy (AFM), photoluminescence, lifetime, and laser beam-induced current (LBIC) measurements. The photocatalytic activity is carried out on TiO2-Cr/PS/Si samples. It was found that the TiO2-Cr/PS/mc-Si type structure degrades an organic pollutant (amido black) under ultraviolet (UV) light. A noticeable degradation of the pollutant is obtained for a Cr doping of 2 at. %. This result is discussed in light of LBIC and photoluminescence measurements.

Comparison of the effect of plasma treatment and gamma ray irradiation on PS-Cu nanocomposite films surface

NASA Astrophysics Data System (ADS)

Farag, O. F.

2018-06-01

Polystyrene-copper (PS-Cu) nanocomposite films were treated with DC N2 plasma and gamma rays irradiations. The plasma treatment of PS-Cu film surface was carried out at different treatment times, gas pressure 0.4 Torr and the applied power 3.5 W. On the other hand, the treatment with gamma rays irradiation were carried out at irradiation doses 10, 30 and 50 kGy. The induced changes in surface properties of PS-Cu films were investigated with UV-viss spectroscopy, scanning electron microscopy (SEM) and FTIR spectroscopy techniques. In addition, the wettability property, surface free energy, spreading coefficient and surface roughness of the treated samples were studied by measuring the contact angle. The UV-viss spectroscopy analysis revealed that the optical band gap decreases with increasing the treatment time and the irradiation dose for plasma and gamma treatments, respectively. SEM observations showed that the particle size of copper particles was increased with increasing the treatment time and the irradiation dose, but gamma treatment changes the copper particles size from nano scale to micro scale. The contact angle measurements showing that the wettability property, surface free energy, spreading coefficient and surface roughness of the treated PS-Cu samples were increased remarkably with increasing the treatment time and the irradiation dose for plasma and gamma treatments, respectively. The contact angle, surface free energy, spreading coefficient and surface roughness of the treated PS-Cu samples are more influenced by plasma treatment than gamma treatment.

Matching on the Disease Risk Score in Comparative Effectiveness Research of New Treatments

PubMed Central

Wyss, Richard; Ellis, Alan R.; Brookhart, M. Alan; Funk, Michele Jonsson; Girman, Cynthia J.; Simpson, Ross J.; Stürmer, Til

2016-01-01

Purpose We use simulations and an empirical example to evaluate the performance of disease risk score (DRS) matching compared with propensity score (PS) matching when controlling large numbers of covariates in settings involving newly introduced treatments. Methods We simulated a dichotomous treatment, a dichotomous outcome, and 100 baseline covariates that included both continuous and dichotomous random variables. For the empirical example, we evaluated the comparative effectiveness of dabigatran versus warfarin in preventing combined ischemic stroke and all-cause mortality. We matched treatment groups on a historically estimated DRS and again on the PS. We controlled for a high-dimensional set of covariates using 20% and 1% samples of Medicare claims data from October 2010 through December 2012. Results In simulations, matching on the DRS versus the PS generally yielded matches for more treated individuals and improved precision of the effect estimate. For the empirical example, PS and DRS matching in the 20% sample resulted in similar hazard ratios (0.88 and 0.87) and standard errors (0.04 for both methods). In the 1% sample, PS matching resulted in matches for only 92.0% of the treated population and a hazard ratio and standard error of 0.89 and 0.19, respectively, while DRS matching resulted in matches for 98.5% and a hazard ratio and standard error of 0.85 and 0.16, respectively. Conclusions When PS distributions are separated, DRS matching can improve the precision of effect estimates and allow researchers to evaluate the treatment effect in a larger proportion of the treated population. However, accurately modeling the DRS can be challenging compared with the PS. PMID:26112690

Matching on the disease risk score in comparative effectiveness research of new treatments.

PubMed

Wyss, Richard; Ellis, Alan R; Brookhart, M Alan; Jonsson Funk, Michele; Girman, Cynthia J; Simpson, Ross J; Stürmer, Til

2015-09-01

We use simulations and an empirical example to evaluate the performance of disease risk score (DRS) matching compared with propensity score (PS) matching when controlling large numbers of covariates in settings involving newly introduced treatments. We simulated a dichotomous treatment, a dichotomous outcome, and 100 baseline covariates that included both continuous and dichotomous random variables. For the empirical example, we evaluated the comparative effectiveness of dabigatran versus warfarin in preventing combined ischemic stroke and all-cause mortality. We matched treatment groups on a historically estimated DRS and again on the PS. We controlled for a high-dimensional set of covariates using 20% and 1% samples of Medicare claims data from October 2010 through December 2012. In simulations, matching on the DRS versus the PS generally yielded matches for more treated individuals and improved precision of the effect estimate. For the empirical example, PS and DRS matching in the 20% sample resulted in similar hazard ratios (0.88 and 0.87) and standard errors (0.04 for both methods). In the 1% sample, PS matching resulted in matches for only 92.0% of the treated population and a hazard ratio and standard error of 0.89 and 0.19, respectively, while DRS matching resulted in matches for 98.5% and a hazard ratio and standard error of 0.85 and 0.16, respectively. When PS distributions are separated, DRS matching can improve the precision of effect estimates and allow researchers to evaluate the treatment effect in a larger proportion of the treated population. However, accurately modeling the DRS can be challenging compared with the PS. Copyright © 2015 John Wiley & Sons, Ltd.

Measurement of the Λb0 Lifetime Using Semileptonic Decays

NASA Astrophysics Data System (ADS)

Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T.; Aguilo, E.; Ahn, S. H.; Ahsan, M.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Anastasoaie, M.; Ancu, L. S.; Andeen, T.; Anderson, S.; Andrieu, B.; Anzelc, M. S.; Arnoud, Y.; Arov, M.; Arthaud, M.; Askew, A.; Åsman, B.; Assis Jesus, A. C. S.; Atramentov, O.; Autermann, C.; Avila, C.; Ay, C.; Badaud, F.; Baden, A.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Banerjee, P.; Barberis, E.; Barfuss, A.-F.; Bargassa, P.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bauer, D.; Beale, S.; Bean, A.; Begalli, M.; Begel, M.; Belanger-Champagne, C.; Bellantoni, L.; Bellavance, A.; Benitez, J. A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Berntzon, L.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Biscarat, C.; Blazey, G.; Blekman, F.; Blessing, S.; Bloch, D.; Bloom, K.; Boehnlein, A.; Boline, D.; Bolton, T. A.; Borissov, G.; Bos, K.; Bose, T.; Brandt, A.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Buchanan, N. J.; Buchholz, D.; Buehler, M.; Buescher, V.; Burdin, S.; Burke, S.; Burnett, T. H.; Buszello, C. P.; Butler, J. M.; Calfayan, P.; Calvet, S.; Cammin, J.; Caron, S.; Carvalho, W.; Casey, B. C. K.; Cason, N. M.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chan, K.; Chandra, A.; Charles, F.; Cheu, E.; Chevallier, F.; Cho, D. K.; Choi, S.; Choudhary, B.; Christofek, L.; Christoudias, T.; Cihangir, S.; Claes, D.; Clément, C.; Clément, B.; Coadou, Y.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Crépé-Renaudin, S.; Cutts, D.; Ćwiok, M.; da Motta, H.; Das, A.; Davies, G.; de, K.; de Jong, S. J.; de Jong, P.; de La Cruz-Burelo, E.; de Oliveira Martins, C.; Degenhardt, J. D.; Déliot, F.; Demarteau, M.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; Dominguez, A.; Dong, H.; Dudko, L. V.; Duflot, L.; Dugad, S. R.; Duggan, D.; Duperrin, A.; Dyer, J.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Eno, S.; Ermolov, P.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Ferapontov, A. V.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Ford, M.; Fortner, M.; Fox, H.; Fu, S.; Fuess, S.; Gadfort, T.; Galea, C. F.; Gallas, E.; Galyaev, E.; Garcia, C.; Garcia-Bellido, A.; Gavrilov, V.; Gay, P.; Geist, W.; Gelé, D.; Gerber, C. E.; Gershtein, Y.; Gillberg, D.; Ginther, G.; Gollub, N.; Gómez, B.; Goussiou, A.; Grannis, P. D.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guo, J.; Guo, F.; Gutierrez, P.; Gutierrez, G.; Haas, A.; Hadley, N. J.; Haefner, P.; Hagopian, S.; Haley, J.; Hall, I.; Hall, R. E.; Han, L.; Hanagaki, K.; Hansson, P.; Harder, K.; Harel, A.; Harrington, R.; Hauptman, J. M.; Hauser, R.; Hays, J.; Hebbeker, T.; Hedin, D.; Hegeman, J. G.; Heinmiller, J. M.; Heinson, A. P.; Heintz, U.; Hensel, C.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hobbs, J. D.; Hoeneisen, B.; Hoeth, H.; Hohlfeld, M.; Hong, S. J.; Hooper, R.; Hossain, S.; Houben, P.; Hu, Y.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jain, S.; Jakobs, K.; Jarvis, C.; Jesik, R.; Johns, K.; Johnson, C.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Juste, A.; Käfer, D.; Kahn, S.; Kajfasz, E.; Kalinin, A. M.; Kalk, J. R.; Kalk, J. M.; Kappler, S.; Karmanov, D.; Kasper, J.; Kasper, P.; Katsanos, I.; Kau, D.; Kaur, R.; Kaushik, V.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. M.; Khatidze, D.; Kim, H.; Kim, T. J.; Kirby, M. H.; Kirsch, M.; Klima, B.; Kohli, J. M.; Konrath, J.-P.; Kopal, M.; Korablev, V. M.; Kothari, B.; Kozelov, A. V.; Krop, D.; Kryemadhi, A.; Kuhl, T.; Kumar, A.; Kunori, S.; Kupco, A.; Kurča, T.; Kvita, J.; Lacroix, F.; Lam, D.; Lammers, S.; Landsberg, G.; Lazoflores, J.; Lebrun, P.; Lee, W. M.; Leflat, A.; Lehner, F.; Lellouch, J.; Lesne, V.; Leveque, J.; Lewin, M.; Lewis, P.; Li, J.; Li, Q. Z.; Li, L.; Lietti, S. M.; Lima, J. G. R.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Liu, Z.; Lobo, L.; Lobodenko, A.; Lokajicek, M.; Lounis, A.; Love, P.; Lubatti, H. J.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Madaras, R. J.; Mättig, P.; Magass, C.; Magerkurth, A.; Makovec, N.; Mal, P. K.; Malbouisson, H. B.; Malik, S.; Malyshev, V. L.; Mao, H. S.; Maravin, Y.; Martin, B.; McCarthy, R.; Melnitchouk, A.; Mendes, A.; Mendoza, L.; Mercadante, P. G.; Merkin, M.; Merritt, K. W.; Meyer, J.; Meyer, A.; Michaut, M.; Millet, T.; Mitrevski, J.; Molina, J.; Mommsen, R. K.; Mondal, N. K.; Moore, R. W.; Moulik, T.; Muanza, G. S.; Mulders, M.; Mulhearn, M.; Mundal, O.; Mundim, L.; Nagy, E.; Naimuddin, M.; Narain, M.; Naumann, N. A.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nilsen, H.; Nomerotski, A.; Novaes, S. F.; Nunnemann, T.; O'Dell, V.; O'Neil, D. C.; Obrant, G.; Ochando, C.; Onoprienko, D.; Oshima, N.; Osta, J.; Otec, R.; Otero Y Garzón, G. J.; Owen, M.; Padley, P.; Pangilinan, M.; Parashar, N.; Park, S.-J.; Park, S. K.; Parsons, J.; Partridge, R.; Parua, N.; Patwa, A.; Pawloski, G.; Penning, B.; Perea, P. M.; Peters, K.; Peters, Y.; Pétroff, P.; Petteni, M.; Piegaia, R.; Piper, J.; Pleier, M.-A.; Podesta-Lerma, P. L. M.; Podstavkov, V. M.; Pogorelov, Y.; Pol, M.-E.; Polozov, P.; Pompoš, A.; Pope, B. G.; Popov, A. V.; Potter, C.; Prado da Silva, W. L.; Prosper, H. B.; Protopopescu, S.; Qian, J.; Quadt, A.; Quinn, B.; Rakitine, A.; Rangel, M. S.; Rani, K. J.; Ranjan, K.; Ratoff, P. N.; Renkel, P.; Reucroft, S.; Rich, P.; Rijssenbeek, M.; Ripp-Baudot, I.; Rizatdinova, F.; Robinson, S.; Rodrigues, R. F.; Royon, C.; Rubinov, P.; Ruchti, R.; Safronov, G.; Sajot, G.; Sánchez-Hernández, A.; Sanders, M. P.; Santoro, A.; Savage, G.; Sawyer, L.; Scanlon, T.; Schaile, D.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schieferdecker, P.; Schliephake, T.; Schmitt, C.; Schwanenberger, C.; Schwartzman, A.; Schwienhorst, R.; Sekaric, J.; Sengupta, S.; Severini, H.; Shabalina, E.; Shamim, M.; Shary, V.; Shchukin, A. A.; Shivpuri, R. K.; Shpakov, D.; Siccardi, V.; Simak, V.; Sirotenko, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Smith, R. P.; Snow, J.; Snow, G. R.; Snyder, S.; Söldner-Rembold, S.; Sonnenschein, L.; Sopczak, A.; Sosebee, M.; Soustruznik, K.; Souza, M.; Spurlock, B.; Stark, J.; Steele, J.; Stolin, V.; Stone, A.; Stoyanova, D. A.; Strandberg, J.; Strandberg, S.; Strang, M. A.; Strauss, M.; Strauss, E.; Ströhmer, R.; Strom, D.; Strovink, M.; Stutte, L.; Sumowidagdo, S.; Svoisky, P.; Sznajder, A.; Talby, M.; Tamburello, P.; Tanasijczuk, A.; Taylor, W.; Telford, P.; Temple, J.; Tiller, B.; Tissandier, F.; Titov, M.; Tokmenin, V. V.; Tomoto, M.; Toole, T.; Torchiani, I.; Trefzger, T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Tuts, P. M.; Unalan, R.; Uvarov, S.; Uvarov, L.; Uzunyan, S.; Vachon, B.; van den Berg, P. J.; van Eijk, B.; van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vartapetian, A.; Vasilyev, I. A.; Vaupel, M.; Verdier, P.; Vertogradov, L. S.; Verzocchi, M.; Villeneuve-Seguier, F.; Vint, P.; Vokac, P.; von Toerne, E.; Voutilainen, M.; Vreeswijk, M.; Wagner, R.; Wahl, H. D.; Wang, L.; Wang, M. H. L. S.; Warchol, J.; Watts, G.; Wayne, M.; Weber, M.; Weber, G.; Weerts, H.; Wenger, A.; Wermes, N.; Wetstein, M.; White, A.; Wicke, D.; Wilson, G. W.; Wimpenny, S. J.; Wobisch, M.; Wood, D. R.; Wyatt, T. R.; Xie, Y.; Yacoob, S.; Yamada, R.; Yan, M.; Yasuda, T.; Yatsunenko, Y. A.; Yip, K.; Yoo, H. D.; Youn, S. W.; Yu, J.; Yu, C.; Yurkewicz, A.; Zatserklyaniy, A.; Zeitnitz, C.; Zhang, D.; Zhao, T.; Zhou, B.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zieminski, A.; Zivkovic, L.; Zutshi, V.; Zverev, E. G.

2007-11-01

We report a measurement of the Λb0 lifetime using a sample corresponding to 1.3fb-1 of data collected by the D0 experiment in 2002 2006 during run II of the Fermilab Tevatron collider. The Λb0 baryon is reconstructed via the decay Λb0→μν¯Λc+X. Using 4437±329 signal candidates, we measure the Λb0 lifetime to be τ(Λb0)=1.290-0.110+0.119(stat)-0.091+0.087(syst)ps, which is among the most precise measurements in semileptonic Λb0 decays. This result is in good agreement with the world average value.

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

LaFreniere, L. M.; Environmental Science Division

In 1992-1993, Argonne National Laboratory investigated potential carbon tetrachloride contamination that might be linked to the former grain storage facility operated by the Commodity Credit Corporation (CCC) of the U.S. Department of Agriculture (USDA) at Utica, Nebraska. These initial studies identified carbon tetrachloride in a plume of contaminated groundwater, extending approximately 3,500 ft southeastward from the former CCC/USDA facility, within a shallow upper aquifer that had been used previously as a municipal water source by the town (Figure 1.1). A deeper aquifer used as the current municipal water source was found to be free of carbon tetrachloride contamination. Although themore » shallow aquifer was no longer being used as a source of drinking water at Utica, additional studies indicated that the carbon tetrachloride could pose an unacceptable health threat to potential future residents who might install private wells along the expected downgradient migration pathway of the plume. On the basis of these findings, corrective action was recommended to decrease the carbon tetrachloride concentrations in the upper aquifer to acceptable levels (Argonne 1993a,b, 1995). Initial discussions with the Utica village board indicated that any restoration strategies involving nonbeneficial discharge of treated groundwater in the immediate vicinity of Utica would be unacceptable to the town. To address this concern, the CCC/USDA and Argonne, in cooperation with multiple federal and state regulatory and environmental agencies (Table 1.1) proposed a treatment strategy for the Utica groundwater employing groundwater extraction coupled with the seasonal use of agricultural spray irrigation equipment to simultaneously (1) remove carbon tetrachloride from the groundwater (by volatilization to the atmosphere) and (2) discharge the treated groundwater to enhance the development of wetlands in the North Lake Basin Wildlife Management Area, just north of the town (Argonne 2000). To develop this treatment approach, additional groundwater sampling was conducted to update the distribution of carbon tetrachloride in groundwater identified in the preliminary studies in 1992-1993. In March 1998, detailed mapping of the carbon tetrachloride plume was performed by using the Argonne cone penetrometer (CPT) vehicle to collect groundwater samples for analyses for volatile organic compounds (VOCs) at 13 locations (PS01-PS09, PS12, PS16, PS17, PS19; Figure 1.2). The samples were collected in vertical profiles through the aquifer, at 10-ft intervals. The results of this 1998 study (Table 1.2) demonstrated that the three-dimensional distribution of carbon tetrachloride in the aquifer is complex, with multiple 'hot spots' occurring in the plume at various depths and distances along its length (Argonne 2000). In October 2002, the CCC/USDA requested that Argonne perform targeted groundwater sampling at Utica to document the migration of the carbon tetrachloride plume since the 1998 sampling event. In February 2003, vertical-profile groundwater sampling for VOCs analyses was conducted at 8 selected locations (PS01, PS04-PS07, PS12, PS19, PS20; Figure 1.2 and Table 1.3). The lateral and vertical configuration of the carbon tetrachloride plume, as identified in the 2003 study (Argonne 2003), is illustrated in Figures 1.3-1.7. On the basis of the 2003 groundwater sampling results, a remedial system employing four extraction wells (GWEX 1-GWEX 4), with groundwater treatment by spray irrigation and conventional air stripping, was implemented at Utica, with the concurrence of the CCC/USDA and the agencies identified in Table 1.1. The principal components of the Utica system (shown in Figure 1.8) are described briefly in Section 1.2. Operation of well GWEX4 and the associated air stripper began on October 29, 2004, and routine operation of wells GWEX1-GWEX3 and the spray irrigation treatment units began on November 22, 2004.« less

Cytological, molecular mechanisms and temperature stress regulating production of diploid male gametes in Dianthus caryophyllus L.

PubMed

Zhou, Xuhong; Mo, Xijun; Gui, Min; Wu, Xuewei; Jiang, Yalian; Ma, Lulin; Shi, Ziming; Luo, Ying; Tang, Wenru

2015-12-01

In plant evolution, because of its key role in sexual polyploidization or whole genome duplication events, diploid gamete formation is considered as an important component in diversification and speciation. Environmental stress often triggers unreduced gamete production. However, the molecular, cellular mechanisms and adverse temperature regulating diplogamete production in carnation remain poorly understood. Here, we investigate the cytological basis for 2n male gamete formation and describe the isolation and characterization of the first gene, DcPS1 (Dianthus Caryophyllus Parallel Spindle 1). In addition, we analyze influence of temperature stress on diploid gamete formation and transcript levels of DcPS1. Cytological evidence indicated that 2n male gamete formation is attributable to abnormal spindle orientation at male meiosis II. DcPS1 protein is conserved throughout the plant kingdom and carries domains suggestive of a regulatory function. DcPS1 expression analysis show DcPS1 gene probably have a role in 2n pollen formation. Unreduced pollen formation in various cultivation was sensitive to high or low temperature which was probably regulated by the level of DcPS1 transcripts. In a broader perspective, these findings can have potential applications in fundamental polyploidization research and plant breeding programs. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Protein C and protein S deficiencies: similarities and differences between two brothers playing in the same game.

PubMed

Bereczky, Zsuzsanna; Kovács, Kitti B; Muszbek, László

2010-12-01

Protein C (PC) and protein S (PS) are vitamin K-dependent glycoproteins that play an important role in the regulation of blood coagulation as natural anticoagulants. PC is activated by thrombin and the resulting activated PC (APC) inactivates membrane-bound activated factor VIII and factor V. The free form of PS is an important cofactor of APC. Deficiencies in these proteins lead to an increased risk of venous thromboembolism; a few reports have also associated these deficiencies with arterial diseases. The degree of risk and the prevalence of PC and PS deficiency among patients with thrombosis and in those in the general population have been examined by several population studies with conflicting results, primarily due to methodological variability. The molecular genetic background of PC and PS deficiencies is heterogeneous. Most of the mutations cause type I deficiency (quantitative disorder). Type II deficiency (dysfunctional molecule) is diagnosed in approximately 5%-15% of cases. The diagnosis of PC and PS deficiencies is challenging; functional tests are influenced by several pre-analytical and analytical factors, and the diagnosis using molecular genetics also has special difficulties. Large gene segment deletions often remain undetected by DNA sequencing methods. The presence of the PS pseudogene makes genetic diagnosis even more complicated.

Use of aspirin, non-steroidal anti-inflammatory drugs, and acetaminophen (paracetamol), and risk of psoriasis and psoriatic arthritis: a cohort study.

PubMed

Wu, Shaowei; Han, Jiali; Qureshi, Abrar A

2015-02-01

Non-steroidal anti-inflammatory drugs (NSAIDs) have been reported to induce or exacerbate psoriasis. We aimed to evaluate the association between several widely used analgesics, including aspirin, non-aspirin NSAIDs, and acetaminophen (paracetamol), and risk of psoriasis and psoriatic arthritis (PsA) in a large cohort of US women, the Nurses' Health Study II (1991-2005). Information on regular use of aspirin, NSAIDs, and acetaminophen was collected for 95,540 participants during the follow-up. During 1,321,280 person-years of follow-up, we documented 646 incident psoriasis cases and 165 concomitant PsA cases. Compared to women who reported no use, regular acetaminophen and NSAIDs users with more than 10 years of use had multivariate hazard ratios of 3.60 [95% confidence interval (CI): 2.02-6.41] and 2.10 (95% CI: 1.11-3.96) for PsA, respectively. There was no clear association between aspirin and risk of psoriasis or PsA. In conclusion, long-term acetaminophen and NSAIDs use may be associated with an increased risk of PsA. Special attention on psoriasis and PsA screening may be needed for those who are prescribed for acetaminophen and NSAIDs for long-term periods.

Sperm membrane functionality in the dog assessed by flow cytometry.

PubMed

Cheuquemán, C; Bravo, P; Treulén, F; Giojalas, Lc; Villegas, J; Sánchez, R; Risopatrón, J

2012-02-01

The objective assessment of sperm function increases the chances of predicting the fertilizing capacity of a fresh semen sample or diagnosing infertility problems. In this study, the available flow cytometry technique was used to determine the membrane functional capacity of canine spermatozoa. The second fractions of ejaculates from six dogs were pooled, and samples (n = 26) processed to determine the variables: sperm viability and plasma membrane integrity by Sybr-14/Pi staining; phosphatidylserine (PS) translocation by Annexin-V-FITC/PI labelling; acrosome membrane integrity by FITC-conjugated Pisum sativum agglutinin/PI labelling; and mitochondrial membrane potential (ΔΨm) by staining with JC-1. Means for the 26 examined samples indicated that 82.66 ± 2.8% of the viable spermatozoa showed an intact plasma membrane, 8.4 ± 2.6% were moribund, 72.7 ± 16% had an intact acrosome, 80.9 ± 17% had high ΔΨm and 8.1 ± 11% had PS translocation with a PS translocation index of 2.1 ± 3%. Motility was only correlated with PS translocation (R = 0.3901; p = 0.0488), and acrosome membrane integrity was correlated with PS translocation (R = -0.5816; p = 0.0018). This study provides objective physiological data on the functional capacity of canine spermatozoa. © 2011 Blackwell Verlag GmbH.

Intensification of UV-C tertiary treatment: Disinfection and removal of micropollutants by sulfate radical based Advanced Oxidation Processes.

PubMed

Rodríguez-Chueca, J; García-Cañibano, C; Lepistö, R-J; Encinas, Á; Pellinen, J; Marugán, J

2018-04-21

This study explores the enhancement of UV-C tertiary treatment by sulfate radical based Advanced Oxidation Processes (SR-AOPs), including photolytic activation of peroxymonosulfate (PMS) and persulfate (PS) and their photocatalytic activation using Fe(II). Their efficiency was assessed both for the inactivation of microorganisms and the removal or micropollutants (MPs) in real wastewater treatment plant effluents. Under the studied experimental range (UV-C dose 5.7-57 J/L; UV-C contact time 3 to 28 s), the photolysis of PMS and PS (0.01 mM) increased up to 25% the bacterial removal regarding to UV-C system. The photolytic activation of PMS led to the total inactivation of bacteria (≈ 5.70 log) with the highest UV-C dose (57 J/L). However, these conditions were insufficient to remove the MPs, being required oxidant's dosages of 5 mM to remove above 90% of carbamazepine, diclofenac, atenolol and triclosan. The best efficiencies were achieved by the combination of PMS or PS with Fe(II), leading to the total removal of the MPs using a low UV-C dosage (19 J/L), UV-C contact time (9 s) and reagent's dosages (0.5 mM). Finally, high mineralization was reached (>50%) with photocatalytic activation of PMS and PS even with low reagent's dosages. Copyright © 2018 Elsevier B.V. All rights reserved.

Elastomeric negative acoustic contrast particles for affinity capture assays.

PubMed

Cushing, Kevin W; Piyasena, Menake E; Carroll, Nick J; Maestas, Gian C; López, Beth Ann; Edwards, Bruce S; Graves, Steven W; López, Gabriel P

2013-02-19

This report describes the development of elastomeric capture microparticles (ECμPs) and their use with acoustophoretic separation to perform microparticle assays via flow cytometry.We have developed simple methods to form ECμPs by cross-linking droplets of common commercially available silicone precursors in suspension followed by surface functionalization with biomolecular recognition reagents. The ECμPs are compressible particles that exhibit negative acoustic contrast in ultrasound when suspended in aqueous media, blood serum, or diluted blood. In this study, these particles have been functionalized with antibodies to bind prostate specific antigen and immunoglobulin (IgG). Specific separation of the ECμPs from blood cells is achieved by flowing them through a microfluidic acoustophoretic device that uses an ultrasonic standing wave to align the blood cells, which exhibit positive acoustic contrast, at a node in the acoustic pressure distribution while aligning the negative acoustic contrast ECμPs at the antinodes. Laminar flow of the separated particles to downstream collection ports allows for collection of the separated negative contrast (ECμPs) and positive contrast particles (cells). Separated ECμPs were analyzed via flow cytometry to demonstrate nanomolar detection for prostate specific antigen in aqueous buffer and picomolar detection for IgG in plasma and diluted blood samples. This approach has potential applications in the development of rapid assays that detect the presence of low concentrations of biomarkers in a number of biological sample types.

Initiation and Modification of Reaction by Energy Addition: Kinetic and Transport Phenomena

DTIC Science & Technology

1990-10-01

ignition- delay time ranges from about 2 to 100 ps. The results of a computer- modeling calcu- lation of the chemical kinetics suggest that the...Page PROGRAM INFORMATION iii 1.0 RESEARCH OBJECTIVES 2.0 ANALYSIS 2 3.0 EXPERIMENT 7 REFERENCES 8 APPENDIX I. Evaluating a Simple Model for Laminar...Flame-Propagation I-1 Rates. I. Planar Geometry. APPENDIX II. Evaluating a Simple Model for Laminar-Flame-Propagation II-1 Rates. II. Spherical

Complementary Cholesterol-Lowering Response of a Phytosterol/α-Lipoic Acid Combination in Obese Zucker Rats

PubMed Central

Rideout, Todd C.; Carrier, Bradley; Wen, Shin; Raslawsky, Amy; Browne, Richard W.; Harding, Scott V.

2015-01-01

To investigate the cholesterol-lowering effectiveness of a phytosterol/α-lipoic acid (PS/αLA) therapy, thirty-two male Zucker rats were randomly assigned to 1 of 4 diets for 30 days: (i) high fat diet (HF, 40% energy from fat); (ii) HF diet supplemented with 3% phytosterols; (iii) HF diet supplemented with 0.25% αLA; or (iv) HF diet supplemented with PS (3%) and αLA (0.25%, PS/αLA). Compared with the HF diet, combination PS/αLA proved more effective in reducing non-HDL cholesterol (−55%) than either the PS (−24%) or the αLA (−25%) therapies alone. PS supplementation did not affect LDL particle number, however, αLA supplementation reduced LDL particle number when supplemented alone (−47%) or in combination with PS (−54%). Compared with the HF-fed animals, evidence of increased HDL-particle number was evident in all treatment groups to a similar extent (21–22%). PS-mediated interruption of intestinal cholesterol absorption was evident by increased fecal cholesterol loss (52%) and compensatory increase in HMG-CoA reductase mRNA (1.6 fold of HF), however, αLA supplementation did not affect fecal cholesterol loss. Hepatic mRNA and protein expression patterns suggested that αLA modulated multiple aspects of cholesterol homeostasis including reduced synthesis (HMG-CoA reductase mRNA, 0.7 fold of HF), reduced bile acid synthesis (CYP7a1 expression, 0.17 of HF), and increased cholesterol clearance (reduced PCSK9 mRNA, 0.5 fold of HF; increased LDLr protein, 2 fold of HF). Taken together, this data suggests that PS and αLA work through unique and complementary mechanisms to provide a superior and more comprehensive cholesterol lowering response than either therapy alone. PMID:25664679

NASA PS400: A New Temperature Solid Lubricant Coating for High Temperature Wear Applications

NASA Technical Reports Server (NTRS)

DellaCorte, C.; Edmonds, B. J.

2009-01-01

A new solid lubricant coating, NASA PS400, has been developed for high temperature tribological applications. This plasma sprayed coating is a variant of the patented PS304 coating and has been formulated to provide higher density, smoother surface finish and better dimensional stability than PS304. PS400 is comprised of a nickel-molybdenum binder that provides strength, creep resistance and extreme oxidative and dimensional stability. Chromium oxide, silver and barium-calcium fluoride eutectic are added to the binder to form PS400.Tribological properties were evaluated with a pin-on-disk test rig in sliding contact to 650 C. Coating material samples were exposed to air, argon and vacuum at 760 C followed by cross section microscopic analysis to assess microstructure stability. Oil-Free microturbine engine hot section foil bearing tests were undertaken to assess PS400 s suitability for hot foil gas bearing applications. The preliminary results indicate that PS400 exhibits tribological characteristics comparable to the PS304 coating but with enhanced creep resistance and dimensional stability suitable for demanding, dynamic applications.

Associating gunpowder and residues from commercial ammunition using compositional analysis.

PubMed

MacCrehan, William A; Reardon, Michelle R; Duewer, David L

2002-03-01

Qualitatively identifying and quantitatively determining the additives in smokeless gunpowder to calculate a numerical propellant to stabilizer (P/S) ratio is a new approach to associate handgun-fired organic gunshot residues (OGSR) with unfired powder. In past work, the P/S values of handgun OGSR and cartridges loaded with known gunpowders were evaluated. In this study, gunpowder and residue samples were obtained from seven boxes of commercial 38 caliber ammunition with the goals of associating cartridges within a box and matching residues to unfired powders, based on the P/S value and the qualitative identity of the additives. Gunpowder samples from four of the seven boxes of ammunition could be easily differentiated. When visual comparisons of the cartridge powders were considered in addition to composition, powder samples from all seven boxes of ammunition could be reliably differentiated. Handgun OGSR was also collected and evaluated in bulk as well as for individual particles. In some cases, residues could be reliably differentiated based on P/S and additive identity. It was instructive to evaluate the composition of individual unfired gunpowder and OGSR particles. We determined that both the numerical centroid and dispersity of the P/S measurements provide information for associations and exclusions. Associating measurements from residue particles with those of residue samples collected from a test firing of the same weapon and ammunition appears to be a useful approach to account for any changes in composition that occur during the firing process.

Origin of the F685 and F695 fluorescence in photosystem II.

PubMed

Andrizhiyevskaya, Elena G; Chojnicka, Agnieszka; Bautista, James A; Diner, Bruce A; van Grondelle, Rienk; Dekker, Jan P

2005-06-01

The emission spectra of CP47-RC and core complexes of Photosystem II (PS II) were measured at different temperatures and excitation wavelengths in order to establish the origin of the emission and the role of the core antenna in the energy transfer and charge separation processes in PS II. Both types of particles reveal strong dependences of spectral shape and yield on temperature. The results indicate that the well-known F-695 emission at 77 K arises from excitations that are trapped on a red-absorbing CP47 chlorophyll, whereas the F-685 nm emission at 77 K arises from excitations that are transferred slowly from 683 nm states in CP47 and CP43 to the RC, where they are trapped by charge separation. We conclude that F-695 at 77 K originates from the low-energy part of the inhomogeneous distribution of the 690 nm absorbing chlorophyll of CP47, while at 4 K the fluorescence originates from the complete distribution of the 690 nm chlorophyll of CP47 and from the low-energy part of the inhomogeneous distribution of one or more CP43 chlorophylls.

Ultrafast Energy Transfer Dynamics Between a Polypyridyl Ru(II) Chromophore and a Covalently Attached Acceptor

NASA Astrophysics Data System (ADS)

Styers-Barnett, David; Gannon, Erika; Papanikolas, John; Meyer, Thomas

2003-03-01

The energy transfer dynamics between the ^3MLCT excited state of a polypyridyl Ru(II) chromophore and a ligand-bound anthracene has been studied using femtosecond transient absorption spectroscopy. Photoexcitation of the metal complex at 450 nm promotes an electron from a d-orbital on the metal to a π* orbital on the bipyridine, forming a metal-to-ligand charge-transfer (MLCT) excited state. Energy transfer to the covalently appended anthracene is followed by the growth of the anthracene excited state absorption at 425 nm, and the simultaneous decay of the ^3MLCT absorption at 380 nm. The observed growth is biexponential, with the fast component attributed to energy transfer (19 ps), and the slow component arising from a combination of interligand electron transfer between the polypyridyl ligands and energy transfer (75 ps).

Carbon dioxide "trapped" in a β-carbonic anhydrase

DOE PAGES

Aggarwal, Mayank; Chua, Teck Khiang; Pinard, Melissa A.; ...

2015-10-12

Carbonic anhydrases (CAs) are enzymes that catalyze the hydration/ dehydration of CO 2/HCO 3 - with rates approaching diffusion-controlled limits (k cat/K M ~ 10 8 M –1s –1). Here, this family of enzymes has evolved disparate protein folds that all perform the same reaction at near catalytic perfection. Presented here is a structural study of a beta-CA (psCA3) expressed in Pseudomonas aeruginosa, in complex with CO 2, using pressurized cryocooled crystallography. The structure has been refined to 1.6 angstrom resolution with R cryst and R free values of 17.3 and 19.9%, respectively, and is compared with the α-CA, humanmore » CA isoform II (hCA II), the only other CA to have CO 2, captured in its active site. Despite the lack of structural similarity between psCA3 and hCA II, the CO 2, binding orientation relative to the zinc-bound solvent is identical. In addition, a second CO 2, binding site was located at the dimer interface of psCA3. Interestingly, all β-CAs function as dirners or higher-order oligomeric states, and the CO 2, bound at the interface may contribute to the allosteric nature of this family of enzymes or may be a convenient alternative binding site as this pocket has been previously shown to be a promiscuous site for a variety of ligands, including bicarbonate, sulfate, and phosphate ions.« less

Keratins Are Altered in Intestinal Disease-Related Stress Responses

PubMed Central

Helenius, Terhi O.; Antman, Cecilia A.; Asghar, Muhammad Nadeem; Nyström, Joel H.; Toivola, Diana M.

2016-01-01

Keratin (K) intermediate filaments can be divided into type I/type II proteins, which form obligate heteropolymers. Epithelial cells express type I-type II keratin pairs, and K7, K8 (type II) and K18, K19 and K20 (type I) are the primary keratins found in the single-layered intestinal epithelium. Keratins are upregulated during stress in liver, pancreas, lung, kidney and skin, however, little is known about their dynamics in the intestinal stress response. Here, keratin mRNA, protein and phosphorylation levels were studied in response to murine colonic stresses modeling human conditions, and in colorectal cancer HT29 cells. Dextran sulphate sodium (DSS)-colitis was used as a model for intestinal inflammatory stress, which elicited a strong upregulation and widened crypt distribution of K7 and K20. K8 levels were slightly downregulated in acute DSS, while stress-responsive K8 serine-74 phosphorylation (K8 pS74) was increased. By eliminating colonic microflora using antibiotics, K8 pS74 in proliferating cells was significantly increased, together with an upregulation of K8 and K19. In the aging mouse colon, most colonic keratins were upregulated. In vitro, K8, K19 and K8 pS74 levels were increased in response to lipopolysaccharide (LPS)-induced inflammation in HT29 cells. In conclusion, intestinal keratins are differentially and dynamically upregulated and post-translationally modified during stress and recovery. PMID:27626448

[Effects of Morus alba and Setaria italica intercropping on their plant growth and diurnal variation of photosynthesis].

PubMed

Zhu, Wen-Xu; Zhang, Hui-Hui; Xu, Nan; Wang, Peng; Wang, Shi-Dan; Mu, Shi-Nan; Liang, Ming; Sun, Guang-Yu

2012-07-01

A field investigation was conducted to study the effects of intercropping Morus aIba and Setaria italica on their dry matter production, land use efficiency, and diurnal variation of leaf photosynthesis. Under intercropping, the plant height, basal diameter, root length, and branch number of M. alba increased by 6.0%, 13.7%, 6.8%, and 14.8%, respectively, and the leaf yield of M. alba was increased by 31.3%, as compared with monoculture M. alba. In contrast, the plant height and root length of intercropped S. italica had no significant difference with those of monoculture S. italica. Intercropping enhanced the equivalent ratio and use efficiency of arable land. For both M. alba and S. italica in monoculture or intercropping, their leaf photosynthetic depression all occurred at midday (12 :00), but the leaf photosynthetic depression of monoculture M. alba was heavier than that of intercropped M. alba. Intercropping promoted the leaf stomatal conductance (g(s)) and water use efficiency (WUE) of M. alba at midday, increased the photosynthetic carbon assimilation of M. alba, and inhibited the decline of M. alba leaf actual photochemical efficiency of PS II (phi(PS II)), photosynthetic electron transport rate (ETR), and the maximal photochemical of PS II (F(v)/F(m)) , which might contribute to alleviate the leaf photosynthetic depression of M. alba at midday. It was concluded that M. alba and S. italica intercropping could obviously improve the leaf photosynthetic capacity of M. alba.

Effects of anesthesia and blood sampling techniques on plasma metabolites and corticosterone in the rat.

PubMed

Arnold, Myrtha; Langhans, Wolfgang

2010-04-19

Blood is routinely sampled from laboratory animals in biomedical research, and many of the commonly applied sampling techniques require anesthesia. Acute effects of many sampling and anesthesia procedures may confound the results, but those effects are incompletely characterized. We here compare the effects of four common anesthesia procedures (inhalation anesthesia with ether (EA) or isoflurane (IA) and intraperitoneal injection anesthesia with xylazin/ketamine (XKA) or medetomidine/midazolam/fentanyl (MMFA)) on plasma concentrations of glucose, lactate, non-esterified fatty acids (NEFAs), and corticosterone in blood obtained from a previously implanted jugular vein (JV) catheter with the effect of JV blood sampling from non-anesthetized, freely-moving rats (JV-NA). Also, we included in the comparison two other blood sampling procedures usually performed without anesthesia (NA), i.e., puncture of the saphenic vein (SV) and tail incision (TI). Whereas the control procedure (JV-NA) did not significantly affect any of the target parameters, plasma glucose increased from 14 (JV-IA) to 44 (JV-MMFA) % (all Ps=0.05 when compared with the control procedure) in all blood samples collected in anesthesia and was 12 and 14% lower (both Ps<0.05) in SV-NA and TI-NA samples, respectively. Plasma lactate increased from 74 (JV-IA) to 226% (SV-NA) (all Ps<0.05) with all sampling and anesthesia procedures except for JV-XKA and JV-MMF. Plasma NEFAs increased to 52% (P<0.05) with the TI-NA procedure and appeared to decrease with the JV-IA and JV-MMFA procedures (both Ps>0.05). Finally, only the JV-EA and the JV-MMFA procedures increased plasma corticosterone (+525 and +353%, respectively, both Ps< 0.05). The JV-IA and JV-XKA procedures appeared to increase it as well, but these differences did not reach statistical significance. Thus, anesthesia and blood sampling procedures can have profound acute effects on plasma metabolite and hormone concentrations. This must be considered for the design and interpretation of blood sampling experiments in laboratory animals. (c) 2010. Published by Elsevier Inc.

High prevalence of shoulder girdle muscles with myofascial trigger points in patients with shoulder pain

PubMed Central

2011-01-01

Background Shoulder pain is reported to be highly prevalent and tends to be recurrent or persistent despite medical treatment. The pathophysiological mechanisms of shoulder pain are poorly understood. Furthermore, there is little evidence supporting the effectiveness of current treatment protocols. Although myofascial trigger points (MTrPs) are rarely mentioned in relation to shoulder pain, they may present an alternative underlying mechanism, which would provide new treatment targets through MTrP inactivation. While previous research has demonstrated that trained physiotherapists can reliably identify MTrPs in patients with shoulder pain, the percentage of patients who actually have MTrPs remains unclear. The aim of this observational study was to assess the prevalence of muscles with MTrPs and the association between MTrPs and the severity of pain and functioning in patients with chronic non-traumatic unilateral shoulder pain. Methods An observational study was conducted. Subjects were recruited from patients participating in a controlled trial studying the effectiveness of physical therapy on patients with unilateral non-traumatic shoulder pain. Sociodemographic and patient-reported symptom scores, including the Disabilities of the Arm, Shoulder, and Hand (DASH) Questionnaire, and Visual Analogue Scales for Pain were compared with other studies. To test for differences in age, gender distribution, and education level between the current study population and the populations from Dutch shoulder studies, the one sample T-test was used. One observer examined all subjects (n = 72) for the presence of MTrPs. Frequency distributions, means, medians, standard deviations, and 95% confidence intervals were calculated for descriptive purposes. The Spearman's rank-order correlation (ρ) was used to test for association between variables. Results MTrPs were identified in all subjects. The median number of muscles with MTrPs per subject was 6 (active MTrPs) and 4 (latent MTrPs). Active MTrPs were most prevalent in the infraspinatus (77%) and the upper trapezius muscles (58%), whereas latent MTrPs were most prevalent in the teres major (49%) and anterior deltoid muscles (38%). The number of muscles with active MTrPs was only moderately correlated with the DASH score. Conclusion The prevalence of muscles containing active and latent MTrPs in a sample of patients with chronic non-traumatic shoulder pain was high. PMID:21711512

Strategies for monitoring the emerging polar organic contaminants in water with emphasis on integrative passive sampling.

PubMed

Söderström, Hanna; Lindberg, Richard H; Fick, Jerker

2009-01-16

Although polar organic contaminants (POCs) such as pharmaceuticals are considered as some of today's most emerging contaminants few of them are regulated or included in on-going monitoring programs. However, the growing concern among the public and researchers together with the new legislature within the European Union, the registration, evaluation and authorisation of chemicals (REACH) system will increase the future need of simple, low cost strategies for monitoring and risk assessment of POCs in aquatic environments. In this article, we overview the advantages and shortcomings of traditional and novel sampling techniques available for monitoring the emerging POCs in water. The benefits and drawbacks of using active and biological sampling were discussed and the principles of organic passive samplers (PS) presented. A detailed overview of type of polar organic PS available, and their classes of target compounds and field of applications were given, and the considerations involved in using them such as environmental effects and quality control were discussed. The usefulness of biological sampling of POCs in water was found to be limited. Polar organic PS was considered to be the only available, but nevertheless, an efficient alternative to active water sampling due to its simplicity, low cost, no need of power supply or maintenance, and the ability of collecting time-integrative samples with one sample collection. However, the polar organic PS need to be further developed before they can be used as standard in water quality monitoring programs.

In situ photoacoustic characterization for porous silicon growing: Detection principles

NASA Astrophysics Data System (ADS)

Ramirez-Gutierrez, C. F.; Castaño-Yepes, J. D.; Rodriguez-García, M. E.

2016-05-01

There are a few methodologies for monitoring the in-situ formation of Porous Silicon (PS). One of the methodologies is photoacoustic. Previous works that reported the use of photoacoustic to study the PS formation do not provide the physical explanation of the origin of the signal. In this paper, a physical explanation of the origin of the photoacoustic signal during the PS etching is provided. The incident modulated radiation and changes in the reflectance are taken as thermal sources. In this paper, a useful methodology is proposed to determine the etching rate, porosity, and refractive index of a PS film by the determination of the sample thickness, using scanning electron microscopy images. This method was developed by carrying out two different experiments using the same anodization conditions. The first experiment consisted of growth of the samples with different etching times to prove the periodicity of the photoacoustic signal, while the second one considered the growth samples using three different wavelengths that are correlated with the period of the photoacoustic signal. The last experiment showed that the period of the photoacoustic signal is proportional to the laser wavelength.

Free-running waveform characterization using a delay-time tunable laser based delay-line-free electro-optic sampling oscilloscope

NASA Astrophysics Data System (ADS)

Lin, Gong-Ru

2002-12-01

We develop a delay-line-free and frequency traceable electro-optic sampling oscilloscope by use of a digital phase-locked loop phase shifter (PLL-PS) controlled delay-time-tunable gain-switched laser diode (GSLD). The home-made voltage-controllable PLL-PS exhibits a linear transfer function with ultra-wide phase shifting range of ±350° and tuning error of <±5%, which benefits the advantages of frequency tracking to free-running signals with suppressed timing-jitter. The maximum delay-time of PLL-PS controlled GSLD is up to 1.95 periods by changing the controlling voltage ( VREF) from -3.5 to 3.5 V, which corresponds to 3.9 ns at repetition frequency of 500 MHz. The tuning responsivity and resolution are about 0.56 ns/V and 0.15˜0.2 ps, respectively. The maximum delay-time switching bandwidth of 100 Hz is determined under the control of a saw-tooth modulated VREF function. The waveform sampling of microwave PECL signals generated from a free-running digital frequency divider is performed with acceptable measuring deviation.

Erlotinib as a single agent in select subsets of patients with advanced non-small-cell lung cancer.

PubMed

Carrión, Ramón Pérez; Gracián, Antonio Cubillo; Hernandez, Pedro Salinas

2007-07-01

Erlotinib is an orally active inhibitor of the epidermal growth factor receptor that is effective for the treatment of non-small-cell lung cancer (NSCLC). Patients with a poor performance status (PS) of 2 constitute up to 40% of advanced NSCLC. This group of patients have a lower life expectancy and are thought to have a greater degree of treatment-related toxicity. The clinical benefit on 238 patients with poor PS included in an open-label, nonrandomized, phase II trial of erlotinib in advanced/metastatic NSCLC was 57.58% defined as complete response plus partial response plus stable disease. Median time to progression was 2.9 months. This review will summarize available data about erlotinib on patients with a PS of 2.

New Interleukins in Psoriasis and Psoriatic Arthritis Patients: The Possible Roles of Interleukin-33 to Interleukin-38 in Disease Activities and Bone Erosions.

PubMed

Li, Jiang; Liu, Lei; Rui, Wenlong; Li, Xiangyu; Xuan, Dandan; Zheng, Shucong; Yu, Yiyun; Zhang, Jiong; Kong, Ning; Zhu, Xiaoxia; Zou, Hejian; Wan, Weiguo; Xue, Yu

2017-01-01

New interleukins (ILs), especially members of IL-1 and IL-12 families, have recently been reported to be involved in the development and regulation of autoimmune and inflammatory diseases. In this study, we aimed to explore the impact of these new ILs in psoriasis (Ps) and psoriatic arthritis (PsA). Forty PsA patients, 20 Ps patients, and 20 healthy controls (HCs) were recruited. Blood samples were obtained for detecting the levels of ILs, IL-12/23p40, and tumor necrosis factor α (TNF-α). The severity of skin lesions was assessed by the Psoriasis Area and Severity Index (PASI). Arthritis activities of PsA patients were assessed by the PsA Joint Activity Index. For PsA patients, circulating osteoclastogenesis-related cytokines (osteoprotegerin and receptor activator of nuclear factor-κB ligand) and numbers of osteoclast precursors were evaluated. Radiographic features of affected joints in these patients were scored for erosion, joint-space narrowing, osteolysis, and new bone formation. Correlations among levels of these ILs, Ps, and PsA disease activities and bone erosions were studied. Ps and PsA patients had higher serum levels of TNF-α, IL-12/23p40, and IL-33. Serum levels of IL-34 and IL-35 were higher in PsA patients than in Ps patients and HCs. Patients with pustular Ps had higher serum levels of IL-36α and IL-38 than patients with Ps vulgaris or HCs. Increased serum levels of IL-36α were positively correlated with PASI. Certain ILs were elevated in the circulation of patients with Ps and PsA, which might contribute to the pathogenesis of skin lesions and arthritis. © 2017 S. Karger AG, Basel.

Characterization of Homopolymer and Polymer Blend Films by Phase Sensitive Acoustic Microscopy

NASA Astrophysics Data System (ADS)

Ngwa, Wilfred; Wannemacher, Reinhold; Grill, Wolfgang

2003-03-01

CHARACTERIZATION OF HOMOPOLYMER AND POLYMER BLEND FILMS BY PHASE SENSITIVE ACOUSTIC MICROSCOPY W Ngwa, R Wannemacher, W Grill Institute of Experimental Physics II, University of Leipzig, 04103 Leipzig, Germany Abstract We have used phase sensitive acoustic microscopy (PSAM) to study homopolymer thin films of polystyrene (PS) and poly (methyl methacrylate) (PMMA), as well as PS/PMMA blend films. We show from our results that PSAM can be used as a complementary and highly valuable technique for elucidating the three-dimensional (3D) morphology and micromechanical properties of thin films. Three-dimensional image acquisition with vector contrast provides the basis for: complex V(z) analysis (per image pixel), 3D image processing, height profiling, and subsurface image analysis of the polymer films. Results show good agreement with previous studies. In addition, important new information on the three dimensional structure and properties of polymer films is obtained. Homopolymer film structure analysis reveals (pseudo-) dewetting by retraction of droplets, resulting in a morphology that can serve as a starting point for the analysis of polymer blend thin films. The outcome of confocal laser scanning microscopy studies, performed on the same samples are correlated with the obtained results. Advantages and limitations of PSAM are discussed.

Measurement of the Lambdab0 lifetime in Lambdab0 --> Lambdac+pi- decays in pp collisions at square root of s = 1.96 TeV.

PubMed

Aaltonen, T; Adelman, J; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bauer, G; Beauchemin, P-H; Bedeschi, F; Beecher, D; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Calancha, C; Camarda, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Chung, K; Chung, W H; Chung, Y S; Chwalek, T; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Corbo, M; Cordelli, M; Cox, C A; Cox, D J; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; de Barbaro, P; De Cecco, S; Deisher, A; De Lorenzo, G; Dell'Orso, M; Deluca, C; Demortier, L; Deng, J; Deninno, M; d'Errico, M; Di Canto, A; di Giovanni, G P; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Dorigo, T; Dube, S; Ebina, K; Elagin, A; Erbacher, R; Errede, D; Errede, S; Ershaidat, N; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; Garcia, J E; Garfinkel, A F; Garosi, P; Gerberich, H; Gerdes, D; Gessler, A; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, S R; Halkiadakis, E; Han, B-Y; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harr, R F; Hartz, M; Hatakeyama, K; Hays, C; Heck, M; Heinrich, J; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Hou, S; Houlden, M; Hsu, S-C; Hughes, R E; Hurwitz, M; Husemann, U; Hussein, M; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jha, M K; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Ketchum, W; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, H W; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Krumnack, N; Kruse, M; Krutelyov, V; Kuhr, T; Kulkarni, N P; Kurata, M; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, E; Lee, H S; Lee, J S; Lee, S W; Leone, S; Lewis, J D; Lin, C-J; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, C; Liu, T; Lockyer, N S; Loginov, A; Lovas, L; Lucchesi, D; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lys, J; Lysak, R; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, M S; Martin, V; Martínez, M; Martínez-Ballarín, R; Mastrandrea, P; Mathis, M; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzione, A; Mesropian, C; Miao, T; Mietlicki, D; Miladinovic, N; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moed, S; Moggi, N; Mondragon, M N; Moon, C S; Moore, R; Morello, M J; Morlock, J; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Nett, J; Neu, C; Neubauer, M S; Neubauer, S; Nielsen, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Osterberg, K; Pagan Griso, S; Pagliarone, C; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramanov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Peiffer, T; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Pianori, E; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Potamianos, K; Poukhov, O; Prokoshin, F; Pronko, A; Ptohos, F; Pueschel, E; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Renton, P; Renz, M; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rodriguez, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Rutherford, B; Saarikko, H; Safonov, A; Sakumoto, W K; Santi, L; Sartori, L; Sato, K; Savoy-Navarro, A; Schlabach, P; Schmidt, A; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sforza, F; Sfyrla, A; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shiraishi, S; Shochet, M; Shon, Y; Shreyber, I; Simonenko, A; Sinervo, P; Sisakyan, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soha, A; Somalwar, S; Sorin, V; Squillacioti, P; Stanitzki, M; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Strycker, G L; Suh, J S; Sukhanov, A; Suslov, I; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tang, J; Tecchio, M; Teng, P K; Thom, J; Thome, J; Thompson, G A; Thomson, E; Tipton, P; Ttito-Guzmán, P; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Tourneur, S; Trovato, M; Tsai, S-Y; Tu, Y; Turini, N; Ukegawa, F; Uozumi, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Vellidis, C; Vidal, M; Vila, I; Vilar, R; Vogel, M; Volobouev, I; Volpi, G; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wagner-Kuhr, J; Wakisaka, T; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Weinelt, J; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Wilbur, S; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wolfe, H; Wright, T; Wu, X; Würthwein, F; Yagil, A; Yamamoto, K; Yamaoka, J; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yi, K; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanetti, A; Zeng, Y; Zhang, X; Zheng, Y; Zucchelli, S

2010-03-12

We report a measurement of the lifetime of the Lambda(b)(0) baryon in decays to the Lambda(c)(+)pi(-) final state in a sample corresponding to 1.1 fb(-1) collected in pp collisions at square root of s = 1.96 TeV by the CDF II detector at the Tevatron collider. Using a sample of about 3000 fully reconstructed Lambda(b)(0) events we measure tau(Lambda(b)(0)) = 1.401 +/- 0.046(stat) +/- 0.035(syst) ps (corresponding to ctau(Lambda(b)(0)) = 420.1 +/- 13.7(stat) +/- 10.6(syst) microm, where c is the speed of light). The ratio of this result and the world average B(0) lifetime yields tau(Lambda(b)(0))/tau(B(0)) = 0.918 +/- 0.038 (stat) and (syst), in good agreement with recent theoretical predictions.

Free-volume characterization of nanostructurized substances by positron annihilation lifetime spectroscopy

NASA Astrophysics Data System (ADS)

Shpotyuk, O.; Ingram, A.; Shpotyuk, Ya.

2018-02-01

Methodological possibilities of positron annihilation lifetime (PAL) spectroscopy are examined to parameterize free-volume structural evolution processes in some nanostructurized substances obeying conversion from positronium (Ps) decaying to positron trapping. Unlike conventional x3-term fitting analysis based on admixed positron trapping and Ps decaying, the effect of nanostructurization is considered as occurring due to conversion from preferential Ps decaying in initial host matrix to positron trapping in modified (nanostructurized) host-guest matrix. The developed approach referred to as x3-x2-CDA (coupling decomposition algorithm) allows estimation defect-free bulk and defect-specific positron lifetimes of free-volume elements responsible for nanostructurization. The applicability of this approach is proved for some nanostructurized materials allowing free-volume changes through Ps-to-positron trapping conversion, such as (i) metallic Ag nanoparticles embedded in polymer matrix, (ii) structure-modification processes caused by swift heavy ions irradiation in polystyrene, and (iii) host-guest chemistry problems like water immersion in alumomagnesium spinel ceramics. This approach is considered to be used as test-indicator, separating processes of host-matrix nanostructurization due to embedded nanoparticles from uncorrelated changes in positron-trapping and Ps-decaying channels.

The "3 in 1" Study: Pooling Self-Taken Pharyngeal, Urethral, and Rectal Samples into a Single Sample for Analysis for Detection of Neisseria gonorrhoeae and Chlamydia trachomatis in Men Who Have Sex with Men.

PubMed

Sultan, B; White, J A; Fish, R; Carrick, G; Brima, N; Copas, A; Robinson, A; Gilson, R; Mercey, D; Benn, P

2016-03-01

Triple-site testing (using pharyngeal, rectal, and urethral/first-void urine samples) for Neisseria gonorrhoeae and Chlamydia trachomatis using nucleic acid amplification tests detects greater numbers of infections among men who have sex with men (MSM). However, triple-site testing represents a cost pressure for services. MSM over 18 years of age were eligible if they requested testing for sexually transmitted infections (STIs), reported recent sexual contact with either C. trachomatis or N. gonorrhoeae, or had symptoms of an STI. Each patient underwent standard-of-care (SOC) triple-site testing, and swabs were taken to form a pooled sample (PS) (pharyngeal, rectal, and urine specimens). The PS was created using two methods during different periods at one clinic, but we analyzed the data in combination because the sensitivity of the two methods did not differ significantly for C. trachomatis (P = 0.774) or N. gonorrhoeae (P = 0.163). The sensitivity of PS testing (92%) was slightly lower than that of SOC testing (96%) for detecting C. trachomatis (P = 0.167). For N. gonorrhoeae, the sensitivity of PS testing (90%) was significantly lower than that of SOC testing (99%) (P < 0.001). When pharynx-only infections were excluded, the sensitivity of PS testing to detect N. gonorrhoeae infections increased to 94%. Our findings show that pooling of self-taken samples could be an effective and cost-saving method, with high negative predictive values. (Interim results of this study were presented at the BASHH 2013 summer meeting.). Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Emotional intelligence and perceived stress.

PubMed

Naidoo, Sudeshni; Pau, Allan

2008-04-01

Many studies have reported that high levels of stress and psychological morbidity occur in students in the health care profession. Stress has been defined as the strain that accompanies a demand perceived to be either challenging (positive) or threatening (negative) and, depending on the appraisal, may be either adaptive or debilitating. The aim of the present survey was to gain some understanding of the explanatory factors for stress and an evaluation of the role that emotional intelligence (EI) plays in the experience of perceived stress (PS). It also aimed to compare EI and PS and explore the association between academic background, satisfaction with career choice and EI, and PS in first year dental students. A cross-sectional survey was conducted at the Faculty of Dentistry, University of the Western Cape. First year dental undergraduates who had completed at least six months of their dental degree course during 2005/06 were invited to complete a set of questionnaires on emotional intelligence and perceived stress. Demographic questions included gender and age. Students were also asked if they had a previous qualification from a higher education institution and if they were satisfied with their decision to study dentistry. Ninety eight completed the questionnaires representing a response rate of 96%. 43 were male (44%) and 55 female (56%), Results of t-tests indicated that low scorers on the EI scale were more likely to be (i) younger compared to older students (p<0.001), (ii) those without compared to those with a previous higher education qualification (p<0.001), and (iii) those who were not satisfied compared to those who were satisfied with their decision to study dentistry (p<0.001). Statistically significant differences were noted in mean PS scores between (i) male and female students (p<0.05), (ii) younger compared to older students (p<0.001), (iii) those without compared to those with previous higher education qualification (p<0.001), and (iv) those who were not satisfied compared to those who were satisfied with their decisions to study dentistry (p<0.001). Correlation analysis between EI and PS indicated a statistically significant inverse relationship between EI and PS (coefficient =-0.50, p=0.001). Stepwise regression analysis identified significant predictors of PS as gender, previous higher education qualification, satisfaction with decision to study dentistry and EI. The t statistic indicates that EI is relatively the most important predictor of PS. The finding that low EI is associated the stress suggests two possible strategies: firstly, selection of prospective students could be based on EI, and there should be interventions to enhance students' emotional intelligence.

Critical de Broglie wavelength in superconductors

NASA Astrophysics Data System (ADS)

Talantsev, E. F.

2018-03-01

There are growing numbers of experimental evidences that the self-field critical currents, Jc(sf,T), are a new instructive tool to investigate fundamental properties of superconductors ranging from atomically thin films [M. Liao et al., Nat. Phys. 6 (2018), https://doi.org/10.1038/s41567-017-0031-6; E. F. Talantsev et al., 2D Mater. 4 (2017) 025072; A. Fete et al., Appl. Phys. Lett. 109 (2016) 192601] to millimeter-scale samples [E. F. Talantsev et al., Sci. Rep. 7 (2017) 10010]. The basic empirical equation which quantitatively accurately described experimental Jc(sf,T) was proposed by Talantsev and Tallon [Nat. Commun. 6 (2015) 7820] and it was the relevant critical field (i.e. thermodynamic field, Bc, for type-I and lower critical field, Bc1, for type-II superconductors) divided by the London penetration depth, λL. In this paper, we report new findings relating to this empirical equation. It is that the critical wavelength of the de Broglie wave, λdB,c, of the superconducting charge carrier which within a numerical pre-factor is equal to the largest of two characteristic lengths of Ginzburg-Landau theory, i.e. the coherence length, ξ, for type-I superconductors or the London penetration depth, λL, for type-II superconductors. We also formulate a microscopic criterion for the onset of dissipative transport current flow: ps ṡ 2ṡλL ln(1+2ṡ(λL ξ )) ≥ 1 2 ṡ ( h 2π), where ps is the charge carrier momentum, h is Planck’s constant and the inequality sign “ <” is reserved for the dissipation-free flow.

Elastomeric Capture Microparticles (ECmuPs) and Their use with Acoustophoresis to Perform Affinity Capture Assays

NASA Astrophysics Data System (ADS)

Cushing, Kevin Wallace

This dissertation describes the development of elastomeric capture microparticles (ECmicroPs) and their use with acoustophoresis to perform affinity capture assays. ECμPs that function as negative acoustic contrast particles were developed by crosslinking emulsion-based droplets composed of commercially available silicone precursors followed by functionalization with avidin/biotin reagents. The size distribution of the ECμPs was very broad or narrow depending on the emulsion system that was used during the synthesis process. Elastomeric particles exhibited a very broad size distribution when a bulk-emulsion process was used; however, when microfluidic systems were utilized, their size distribution became comparatively narrow. The functionalization of elastomeric particles was accomplished by the non-specific adsorption of avidin protein followed by bovine serum albumin (BSA) blocking and bio-specific adsorption of a biotinylated-capture antibody. Polydisperse ECμPs were functionalized to bind prostate specific antigen (PSA) or IgG-phycoerythrin (PE) in aqueous media (buffer, plasma, blood); whereas monodisperse ECμPs were functionalized to bind a high density lipoprotein in the aqueous media. Polydisperse ECμPs functionalized to bind PSA in a physiological buffer (PBS pH 7.4) demonstrated nanomolar detection using flow cytometry analysis; whereas ECμPs functionalized to bind IgG-PE demonstrated picomolar detection in 10% porcine plasma. ECμPs have a specific density of ~1.03 and are more compressible than their surrounding aqueous media; which allowed the ECμPs to exhibit negative acoustic contrast properties under an ultrasonic acoustic standing wave field. The negative acoustic contrast property of ECμPs was advantageously utilized in an IgG-PE assay conducted in 0.1% whole porcine blood. The ligand-bound ECμPs suspended in the diluted blood sample were flowed through an acoustofluidic device where the application of an ultrasonic acoustic standing wave field focused the ligand-bound ECμPs to pressure antinodes and the positive acoustic contrast blood cells to the central pressure node of the microchannel. As a result of laminar flow, focused ligand-bound ECμPs and blood cells were flowed into properly aligned outlet channels at the downstream trifurcation, where they where collected separately off-chip. The cell-free fraction containing ligand-bound ECμPs was analyzed using flow cytometry; where the detection of IgG-PE was in the picomolar range. This approach has potential applications in the development of rapid assays that detect the presence of low concentrations of biomarkers in a number of biological sample types.

An educational overview of the chemistry, biochemistry and therapeutic aspects of Mn porphyrins--From superoxide dismutation to H2O2-driven pathways.

PubMed

Batinic-Haberle, Ines; Tovmasyan, Artak; Spasojevic, Ivan

2015-08-01

Most of the SOD mimics thus far developed belong to the classes of Mn-(MnPs) and Fe porphyrins(FePs), Mn(III) salens, Mn(II) cyclic polyamines and metal salts. Due to their remarkable stability we have predominantly explored Mn porphyrins, aiming initially at mimicking kinetics and thermodynamics of the catalysis of O2(-) dismutation by SOD enzymes. Several MnPs are of potency similar to SOD enzymes. The in vivo bioavailability and toxicity of MnPs have been addressed also. Numerous in vitro and in vivo studies indicate their impressive therapeutic efficacy. Increasing insight into complex cellular redox biology has been accompanied by increasing awareness of complex redox chemistry of MnPs. During O2(-) dismutation process, the most powerful Mn porphyrin-based SOD mimics reduce and oxidize O2(-) with close to identical rate constants. MnPs reduce and oxidize other reactive species also (none of them specific to MnPs), acting as reductants (antioxidant) and pro-oxidants. Distinction must be made between the type of reactions of MnPs and the favorable therapeutic effects we observe; the latter may be of either anti- or pro-oxidative nature. H2O2/MnP mediated oxidation of protein thiols and its impact on cellular transcription seems to dominate redox biology of MnPs. It has been thus far demonstrated that the ability of MnPs to catalyze O2(-) dismutation parallels all other reactivities (such as ONOO(-) reduction) and in turn their therapeutic efficacies. Assuming that all diseases have in common the perturbation of cellular redox environment, developing SOD mimics still seems to be the appropriate strategy for the design of potent redox-active therapeutics. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Innovative combination of electrolysis and Fe(II)-activated persulfate oxidation for improving the dewaterability of waste activated sludge.

PubMed

Zhen, Guang-Yin; Lu, Xue-Qin; Li, Yu-You; Zhao, You-Cai

2013-05-01

The feasibility of electrolysis integrated with Fe(II)-activated persulfate (S2O8(2-)) oxidation to improve waste activated sludge (WAS) dewaterability was evaluated. The physicochemical properties (sludge volume (SV), total suspended solids (TSS) and volatile suspended solids (VSS)) and extracellular polymeric substances (EPS), including slime EPS, loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS) were characterized to identify their exact roles in sludge dewatering. While dewaterability negatively corresponded to LB-EPS, TB-EPS, protein (PN) and polysaccharide (PS) in LB-EPS and TB-EPS, it was independent of SV, TSS, VSS, slime EPS and PN/PS. Further study through scanning electron microscope (SEM) verified the entrapment of bacterial cells by TB-EPS, protecting them against electrolysis disruption. Comparatively, electrolysis integrated with S2O8(2-)/Fe(II) oxidation was able to effectively disrupt the protective barrier and crack the entrapped cells, releasing the water inside EPS and cells. Therefore, the destruction of both TB-EPS and cells is the fundamental reason for the enhanced dewaterability. Copyright © 2013 Elsevier Ltd. All rights reserved.

Polymerization stress evolution of a bulk-fill flowable composite under different compliances.

PubMed

Guo, Yongwen; Landis, Forrest A; Wang, Zhengzhi; Bai, Ding; Jiang, Li; Chiang, Martin Y M

2016-04-01

To use a compliance-variable instrument to simultaneously measure and compare the polymerization stress (PS) evolution, degree of conversion (DC), and exotherm of a bulk-fill flowable composite to a packable composite. A bulk-fill flowable composite (Filtek Bulk-fill, FBF) and a conventional packable composite (Filtek Z250, Z250) purchased from 3M ESPE were investigated. The composites were studied using a cantilever-beam based instrument equipped with an in situ near infrared (NIR) spectrometer and a microprobe thermocouple. The measurements were carried out under various instrumental compliances (ranging from 0.3327μm/N to 12.3215μm/N) that are comparable to the compliances of clinically prepared tooth cavities. Correlations between the PS and temperature change as well as the DC were interpreted. The maximum PS of both composites at 10min after irradiation decreased with the increase in the compliance of the cantilever beam. The FBF composite generated a lower final stress than the Z250 sample under instrumental compliances less than ca. 4μm/N; however, both materials generated statistically similar PS values at higher compliances. The reaction exotherm and the DC of both materials were found to be independent of compliance. The DC of the FBF sample was slightly higher than that of the packable Z250 composite while the peak exotherm of FBF was almost double that of the Z250 composite. For FBF, a characteristic drop in the PS was observed during the early stage of polymerization for all compliances studied which was not observed in the Z250 sample. This drop was shown to relate to the greater exotherm of the less-filled FBF sample relative to the Z250 composite. While the composites with lower filler content (low viscosity) are generally considered to have lower PS than the conventional packable composites, a bulk-fill flowable composite was shown to produce lower PS under a lower compliance of constraint as would be experienced if the composite was used as the base material in clinical procedures. Published by Elsevier Ltd.

Transcriptional and physiological analyses of Fe deficiency response in maize reveal the presence of Strategy I components and Fe/P interactions.

PubMed

Zanin, Laura; Venuti, Silvia; Zamboni, Anita; Varanini, Zeno; Tomasi, Nicola; Pinton, Roberto

2017-02-13

Under limited iron (Fe) availability maize, a Strategy II plant, improves Fe acquisition through the release of phytosiderophores (PS) into the rhizosphere and the subsequent uptake of Fe-PS complexes into root cells. Occurrence of Strategy-I-like components and interactions with phosphorous (P) nutrition has been hypothesized based on molecular and physiological studies in grasses. In this report transcriptomic analysis (NimbleGen microarray) of Fe deficiency response revealed that maize roots modulated the expression levels of 724 genes (508 up- and 216 down-regulated, respectively). As expected, roots of Fe-deficient maize plants overexpressed genes involved in the synthesis and release of 2'-deoxymugineic acid (the main PS released by maize roots). A strong modulation of genes involved in regulatory aspects, Fe translocation, root morphological modification, primary metabolic pathways and hormonal metabolism was induced by the nutritional stress. Genes encoding transporters for Fe 2+ (ZmNRAMP1) and P (ZmPHT1;7 and ZmPHO1) were also up-regulated under Fe deficiency. Fe-deficient maize plants accumulated higher amounts of P than the Fe-sufficient ones, both in roots and shoots. The supply of 1 μM 59 Fe, as soluble (Fe-Citrate and Fe-PS) or sparingly soluble (Ferrihydrite) sources to deficient plants, caused a rapid down-regulation of genes coding for PS and Fe(III)-PS transport, as well as of ZmNRAMP1 and ZmPHT1;7. Levels of 32 P absorption essentially followed the rates of 59 Fe uptake in Fe-deficient plants during Fe resupply, suggesting that P accumulation might be regulated by Fe uptake in maize plants. The transcriptional response to Fe-deficiency in maize roots confirmed the modulation of known genes involved in the Strategy II and revealed the presence of Strategy I components usually described in dicots. Moreover, data here presented provide evidence of a close relationship between two essential nutrients for plants, Fe and P, and highlight a key role played by Fe and P transporters to preserve the homeostasis of these two nutrients in maize plants.

Probing the phosphatidylinositol 3-kinase/mammalian target of rapamycin pathway in gliomas: A phase 2 study of everolimus for recurrent adult low-grade gliomas.

PubMed

Wahl, Michael; Chang, Susan M; Phillips, Joanna J; Molinaro, Annette M; Costello, Joseph F; Mazor, Tali; Alexandrescu, Sanda; Lupo, Janine M; Nelson, Sarah J; Berger, Mitchel; Prados, Michael; Taylor, Jennie W; Butowski, Nicholas; Clarke, Jennifer L; Haas-Kogan, Daphne

2017-12-01

Activation of the phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathway is common in patients with low-grade gliomas (LGGs), but agents that inhibit this pathway, including mTOR inhibitors, have not been studied in this population. Fifty-eight patients with pathologic evidence of recurrence after they had initially been diagnosed with World Health Organization (WHO) grade II gliomas were enrolled into a prospective phase 2 clinical trial and received daily everolimus (RAD001) for 1 year or until progression. Tissue at the time of enrollment was analyzed for markers of PI3K/mTOR pathway activation. Thirty-eight patients underwent serial multiparametric magnetic resonance imaging, with the tumor volume and the perfusion metrics (the fractional blood volume [fBV] for capillary density and the transfer coefficient [K ps ] for vascular permeability) measured during treatment. The primary endpoint was progression-free survival at 6 months (PFS-6) in patients with WHO II disease at enrollment. For patients with WHO II gliomas at enrollment, the PFS-6 rate was 84%, and this met the primary endpoint (P < .001 for an improvement from the historical rate of 17%). Evidence of PI3K/mTOR activation by immunohistochemistry for phosphorylated ribosomal S6 Ser240/244 (p-S6 Ser240/244 ) was associated with worse progression-free survival (PFS; hazard ratio [HR], 3.03; P = .004) and overall survival (HR, 12.7; P = .01). Tumor perfusion decreased after 6 months (median decrease in fBV, 15%; P = .03; median decrease in K ps , 12%; P = .09), with greater decreases associated with improved PFS (HR for each 10% fBV decrease, 0.71; P = .01; HR for each 10% K ps decrease, 0.82; P = .04). Patients with recurrent LGGs demonstrated a high degree of disease stability during treatment with everolimus. PI3K/mTOR activation, as measured by immunohistochemistry for p-S6, was associated with a worse prognosis. Tumor vascular changes were observed that were consistent with the antiangiogenic effects of mTOR inhibitors. These results support further study of everolimus for LGGs. Cancer 2017;123:4631-4639. © 2017 American Cancer Society. © 2017 American Cancer Society.

Quantitative determination of fatty acids in marine fish and shellfish from warm water of Straits of Malacca for nutraceutical purposes.

PubMed

Abd Aziz, Nurnadia; Azlan, Azrina; Ismail, Amin; Mohd Alinafiah, Suryati; Razman, Muhammad Rizal

2013-01-01

This study was conducted to quantitatively determine the fatty acid contents of 20 species of marine fish and four species of shellfish from Straits of Malacca. Most samples contained fairly high amounts of polyunsaturated fatty acids (PUFAs), especially alpha-linolenic acid (ALA, C18:3 n3), eicosapentaenoic acid (EPA, C20:5 n3), and docosahexaenoic acid (DHA, C22:6 n3). Longtail shad, yellowstripe scad, and moonfish contained significantly higher (P < 0.05) amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA), respectively. Meanwhile, fringescale sardinella, malabar red snapper, black pomfret, Japanese threadfin bream, giant seaperch, and sixbar grouper showed considerably high content (537.2-944.1 mg/100 g wet sample) of desirable omega-3 fatty acids. The polyunsaturated-fatty-acids/saturated-fatty-acids (P/S) ratios for most samples were higher than that of Menhaden oil (P/S = 0.58), a recommended PUFA supplement which may help to lower blood pressure. Yellowstripe scad (highest DHA, ω - 3/ω - 6 = 6.4, P/S = 1.7), moonfish (highest ALA, ω - 3/ω - 6 = 1.9, P/S = 1.0), and longtail shad (highest EPA, ω - 3/ω - 6 = 0.8, P/S = 0.4) were the samples with an outstandingly desirable overall composition of fatty acids. Overall, the marine fish and shellfish from the area contained good composition of fatty acids which offer health benefits and may be used for nutraceutical purposes in the future.

Quantitative Determination of Fatty Acids in Marine Fish and Shellfish from Warm Water of Straits of Malacca for Nutraceutical Purposes

PubMed Central

Abd Aziz, Nurnadia; Azlan, Azrina; Ismail, Amin; Mohd Alinafiah, Suryati; Razman, Muhammad Rizal

2013-01-01

This study was conducted to quantitatively determine the fatty acid contents of 20 species of marine fish and four species of shellfish from Straits of Malacca. Most samples contained fairly high amounts of polyunsaturated fatty acids (PUFAs), especially alpha-linolenic acid (ALA, C18:3 n3), eicosapentaenoic acid (EPA, C20:5 n3), and docosahexaenoic acid (DHA, C22:6 n3). Longtail shad, yellowstripe scad, and moonfish contained significantly higher (P < 0.05) amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA), respectively. Meanwhile, fringescale sardinella, malabar red snapper, black pomfret, Japanese threadfin bream, giant seaperch, and sixbar grouper showed considerably high content (537.2–944.1 mg/100g wet sample) of desirable omega-3 fatty acids. The polyunsaturated-fatty-acids/saturated-fatty-acids (P/S) ratios for most samples were higher than that of Menhaden oil (P/S = 0.58), a recommended PUFA supplement which may help to lower blood pressure. Yellowstripe scad (highest DHA, ω − 3/ω − 6 = 6.4, P/S = 1.7), moonfish (highest ALA, ω − 3/ω − 6 = 1.9, P/S = 1.0), and longtail shad (highest EPA, ω − 3/ω − 6 = 0.8, P/S = 0.4) were the samples with an outstandingly desirable overall composition of fatty acids. Overall, the marine fish and shellfish from the area contained good composition of fatty acids which offer health benefits and may be used for nutraceutical purposes in the future. PMID:23509703

7 CFR 1753.47 - Plans and specifications (P&S).

Code of Federal Regulations, 2014 CFR

2014-01-01

... the Loan Design (LD) shall be revised to reflect any needed changes (See § 1753.3). (ii) Deviations... units and guide drawings, if any. (4) Key, detail, and cable layout maps. (5) RUS Contract Form 787...

7 CFR 1753.47 - Plans and specifications (P&S).

Code of Federal Regulations, 2011 CFR

2011-01-01

... the Loan Design (LD) shall be revised to reflect any needed changes (See § 1753.3). (ii) Deviations... units and guide drawings, if any. (4) Key, detail, and cable layout maps. (5) RUS Contract Form 787...

7 CFR 1753.47 - Plans and specifications (P&S).

Code of Federal Regulations, 2012 CFR

2012-01-01

... the Loan Design (LD) shall be revised to reflect any needed changes (See § 1753.3). (ii) Deviations... units and guide drawings, if any. (4) Key, detail, and cable layout maps. (5) RUS Contract Form 787...

7 CFR 1753.47 - Plans and specifications (P&S).

Code of Federal Regulations, 2013 CFR

2013-01-01

... the Loan Design (LD) shall be revised to reflect any needed changes (See § 1753.3). (ii) Deviations... units and guide drawings, if any. (4) Key, detail, and cable layout maps. (5) RUS Contract Form 787...

7 CFR 1753.47 - Plans and specifications (P&S).

Code of Federal Regulations, 2010 CFR

2010-01-01

... the Loan Design (LD) shall be revised to reflect any needed changes (See § 1753.3). (ii) Deviations... units and guide drawings, if any. (4) Key, detail, and cable layout maps. (5) RUS Contract Form 787...

Association between cell-derived microparticles and adverse events in patients with nonpulsatile left ventricular assist devices

PubMed Central

Nascimbene, Angelo; Hernandez, Ruben; George, Joggy K.; Parker, Anita; Bergeron, Angela L.; Pradhan, Subhashree; Vijayan, K. Vinod; Civitello, Andrew; Simpson, Leo; Nawrot, Maria; Lee, Vei-Vei; Mallidi, Hari R.; Delgado, Reynolds M.; Dong, Jing Fei; Frazier, O.H.

2014-01-01

BACKGROUND Continuous-flow left ventricular assist devices (LVADs) expose blood cells to high shear stress, potentially resulting in the production of microparticles that express phosphatidylserine (PS+) and promote coagulation and inflammation. In this prospective study, we attempted to determine whether PS+ microparticle levels correlate with clinical outcomes in LVAD-supported patients. METHODS We enrolled 20 patients undergoing implantation of the HeartMate II LVAD and 10 healthy controls who provided reference values for the microparticle assays. Plasma was collected before LVAD implantation, at discharge, at 3-month follow-up, and when an adverse clinical event occurred. We quantified PS+ microparticles in the plasma using flow cytometry. RESULTS During the study period, 8 patients developed adverse clinical events: ventricular tachycardia storm (n=1), non–ST-elevation myocardial infarction (n=2), arterial thrombosis (n=2), gastrointestinal bleeding (n=2), and stroke (n=3). Levels of PS+ microparticles were higher in patients at baseline than in healthy controls (2.11%±1.26 vs 0.69±0.46, P=0.007). After LVAD implantation, patient PS+ microparticle levels increased to 2.39%±1.22 at discharge and then leveled to 1.97%±1.25 at 3-month follow-up. Importantly, patients who developed an adverse event had significantly higher levels of PS+ microparticles than did patients with no events (3.82%±1.17 vs 1.57%±0.59, P<0.001), even though the 2 patient groups did not markedly differ in other clinical and hematologic parameters. CONCLUSIONS Our results suggest that an elevation of PS+ microparticle levels may be associated with adverse clinical events. Thus, measuring PS+ microparticle levels in LVAD-supported patients may help identify patients at increased risk for adverse events. PMID:24656391

Synthesis, Structural, and Adsorption Properties and Thermal Stability of Nanohydroxyapatite/Polysaccharide Composites.

PubMed

Skwarek, Ewa; Goncharuk, Olena; Sternik, Dariusz; Janusz, Wladyslaw; Gdula, Karolina; Gun'ko, Vladimir M

2017-12-01

A series of composites based on nanohydroxyapatite (nHAp) and natural polysaccharides (PS) (nHAp/agar, nHAp/chitosan, nHAp/pectin FB300, nHAp/pectin APA103, nHAp/sodium alginate) was synthesized by liquid-phase two-step method and characterized using nitrogen adsorption-desorption, DSC, TG, FTIR spectroscopy, and SEM. The analysis of nitrogen adsorption-desorption data shows that composites with a nHAp: PS ratio of 4:1 exhibit a sufficiently high specific surface area from 49 to 82 m 2 /g. The incremental pore size distributions indicate mainly mesoporosity. The composites with the component ratio 1:1 preferably form a film-like structure, and the value of S BET varies from 0.3 to 43 m 2 /g depending on the nature of a polysaccharide. Adsorption of Sr(II) on the composites from the aqueous solutions has been studied. The thermal properties of polysaccharides alone and in nHAp/PS show the influence of nHAp, since there is a shift of characteristic DSC and DTG peaks. FTIR spectroscopy data confirm the presence of functional groups typical for nHAp as well as polysaccharides in composites. Structure and morphological characteristics of the composites are strongly dependent on the ratio of components, since nHAp/PS at 4:1 have relatively large S BET values and a good ability to adsorb metal ions. The comparison of the adsorption capacity with respect to Sr(II) of nHAp, polysaccharides, and composites shows that it of the latter is higher than that of nHAp (per 1 m 2 of surface).

Mid-infrared Flare of TDE Candidate PS16dtm: Dust Echo and Implications for the Spectral Evolution

NASA Astrophysics Data System (ADS)

Jiang, Ning; Wang, Tinggui; Yan, Lin; Xiao, Ting; Yang, Chenwei; Dou, Liming; Wang, Huiyuan; Cutri, Roc; Mainzer, Amy

2017-11-01

PS16dtm was classified as a candidate tidal disruption event in a dwarf Seyfert 1 galaxy with a low-mass black hole (˜ {10}6 {M}⊙ ) and has presented various intriguing photometric and spectra characteristics. Using the archival Wide-field Infrared Survey Explorer and the newly released NEOWISE data, we found that PS16dtm is experiencing a mid-infrared (MIR) flare that started ˜11 days before the first optical detection. Interpreting the MIR flare as a dust echo requires close pre-existing dust with a high covering factor and suggests that the optical flare may have brightened slowly for some time before it became bright detectable from the ground. More evidence is given at the later epochs. At the peak of the optical light curve, the new inner radius of the dust torus has grown to a much larger size (I.e., a factor of seven of the initial radius) due to the strong radiation field. At ˜150 days after the first optical detection, the dust temperature has dropped well below the sublimation temperature. Other peculiar spectral features shown by PS16dtm are the transient, prominent Fe II emission lines and outflows indicated by broad absorption lines detected during the optical flare. Our model explains the enhanced Fe II emission from iron that is newly released from the evaporated dust. The observed broad absorption line outflow could be explained by accelerated gas in the dust torus due to the radiation pressure.

Adaptation of Chinese and English versions of the Psoriatic Arthritis Quality of Life (PsAQoL) scale for use in Singapore.

PubMed

Leung, Ying Ying; Thumboo, Julian; Rouse, Matthew; McKenna, Stephen P

2016-10-18

To develop Singapore Chinese and English versions of the Psoriatic Arthritis Quality of Life (PsAQoL) scale that were equivalent to and met the same psychometric and acceptability standards as the original UK measure. Translation of the original PsAQoL into contextualised English and Chinese versions for use in Singapore was performed by professional and lay translation panels. Ten Chinese speaking and ten English speaking local patients were interviewed to assess face and content validity. Psoriatic arthritis (PsA) patients (either Chinese or English speaking) fulfilling the Classification criteria of Psoriatic Arthritis were then invited to participate in a validation survey. Clinical variables, the Health Assessment Questionnaire (HAQ) and the Medical Outcome Short-form 36 (SF-36) were used as comparator instruments for convergent validity. A separate sample of PsA patients were invited to participate in a test-retest postal study, with two weeks between administrations. The validation sample included 98 patients (51 % men) with a mean (SD) age of 51.5 (13.8) years. The PsAQoL had excellent internal consistency (Cronbach's α = 0.92) and scores on the measure were moderately correlated with health status measures (pain, HAQ score, SF-36 scores) and patient and physician global assessments. The scale was able to distinguish between groups with active or inactive disease assessed by composite scores, HAQ and minimal disease activity. Test-retest reliability was excellent (r = 0.92). This study provides evidence that the adapted English and Chinese versions of the PsAQoL can be used in clinical studies with PsA patients in Singapore.

Use of X-ray absorption near edge structure (XANES) to identify physisorption and chemisorption of phosphate onto ferrihydrite-modified diatomite.

PubMed

Xiong, Wenhui; Peng, Jian; Hu, Yongfeng

2012-02-15

This paper presents a novel technique integrating bulk-sensitive and surface-sensitive XANES methods to distinguish between physisorption and chemisorption for phosphate adsorption onto ferrihydrite-modified diatomite (FHMD). XANES P K-edge, L-edge, and Fe M-edge spectra were obtained for reference samples (K(2)HPO(4) and FePO(4)·2H(2)O) and test samples (phosphate adsorbed onto FHMD (FHMD-Ps) and Si-containing ferrihydrite (FHYD-Ps)). A resolvable pre-edge peak in the P K-edge spectra of FHMD-Ps and FHYD-Ps provided direct evidence for the formation of P-O-Fe(III) coordination and the occurrence of chemisorption. The resemblance between the P L-edge spectra of K(2)HPO(4) and FHMD-Ps and the marked difference between the spectra of FHMD-Ps and FePO(4)·2H(2)O indicated the intact existence of the adsorbate and the adsorbent. The similarity between Fe M-edge spectra of FHMD and FHMD-Ps and the difference between the spectra of FHMD-Ps and FePO(4)·2H(2)O confirmed the findings from P L-edge analyses. Therefore, chemisorption and physisorption coexisted during phosphate adsorption onto FHMD. Phosphate chemisorption occurred in the deeper zone of FHMD (from 50 nm to 5 μm); whereas physisorption occurred in the zone of FHMD shallower than 50 nm since the probing depth of XANES P K-edge method is 5 μm and that of P L-edge and Fe M-edge methods is 50 nm. Copyright © 2011 Elsevier Inc. All rights reserved.

Alpha/beta pulse shape discrimination in plastic scintillation using commercial scintillation detectors.

PubMed

Bagán, H; Tarancón, A; Rauret, G; García, J F

2010-06-18

Activity determination in different types of samples is a current need in many different fields. Simultaneously analysing alpha and beta emitters is now a routine option when using liquid scintillation (LS) and pulse shape discrimination. However, LS has an important drawback, the generation of mixed waste. Recently, several studies have shown the capability of plastic scintillation (PS) as an alternative to LS, but no research has been carried out to determine its capability for alpha/beta discrimination. The objective of this study was to evaluate the capability of PS to discriminate alpha/beta emitters on the basis of pulse shape analysis (PSA). The results obtained show that PS pulses had lower energy than LS pulses. As a consequence, a lower detection efficiency, a shift to lower energies and a better discrimination of beta and a worst discrimination of alpha disintegrations was observed for PS. Colour quenching also produced a decrease in the energy of the particles, as well as the effects described above. It is clear that in PS, the discrimination capability was correlated with the energy of the particles detected. Taking into account the discrimination capabilities of PS, a protocol for the measurement and the calculation of alpha and beta activities in mixtures using PS and commercial scintillation detectors has been proposed. The new protocol was applied to the quantification of spiked river water samples containing a pair of radionuclides ((3)H-(241)Am or (90)Sr/(90)Y-(241)Am) in different activity proportions. The relative errors in all determinations were lower than 7%. These results demonstrate the capability of PS to discriminate alpha/beta emitters on the basis of pulse shape and to quantify mixtures without generating mixed waste. 2010 Elsevier B.V. All rights reserved.

Structure and photoluminescence properties of ZnS films grown on porous Si substrates

NASA Astrophysics Data System (ADS)

Wang, Cai-feng; Hu, Bo; Yi, Hou-hui; Li, Wei-bing

2011-11-01

ZnS films were deposited on porous silicon (PS) substrates with different porosities. With the increase of PS substrate porosity, the XRD diffraction peak intensity decreases and the surface morphology of the ZnS films becomes rougher. Voids appear in the films, due to the increased roughness of PS structure. The photoluminescence (PL) spectra of the samples before and after deposition of ZnS were measured to study the effect of substrate porosity on the luminescence properties of ZnS/PS composites. As-prepared PS substrates emit strong red light. The red PL peak of PS after deposition of ZnS shows an obvious blueshift. As PS substrate porosity increases, the trend of blueshift increases. A green emission at about 550 nm was also observed when the porosity of PS increased, which is ascribed to the defect-center luminescence of ZnS. The effect of annealing time on the structural and luminescence properties of ZnS/PS composites were also studied. With the increase of annealing time, the XRD diffraction peak intensity and the self-activated luminescence intensity of ZnS increase, and, the surface morphology of the ZnS films becomes smooth and compact. However, the red emission intensity of PS decreases, which was associated with a redshift. White light emission was obtained by combining the luminescence of ZnS with the luminescence of PS.

Psoriatic Arthritis Quality of Life questionnaire: translation, cultural adaptation and validation into Portuguese language.

PubMed

Barcelos, Anabela; Ambrósio, Catarina; Pereira da Silva, J A; McKenna, Stephen; Wilburn, Jeanette; Lopes Ferreira, Pedro

2018-02-01

Psoriatic arthritis (PsA) has a strong negative impact on the quality of life of patients. The Psoriatic Arthritis Quality of Life (PsAQoL) questionnaire is a disease-specific instrument developed to measure the quality of life in patients with PsA. The aims of this study were to culturally adapt the questionnaire for Portugal and evaluate its reliability and validity in patients with PsA. The original UK English version of the PsAQoL was translated into Portuguese by a bilingual and lay panel. Structured cognitive debriefing interviews were conducted with ten PsA patients. The Portuguese PsAQoL was subsequently applied to PsA patients followed at the Rheumatology Department of Centro Hospitalar do Baixo Vouga, E.P.E. To assess reproducibility, 30 patients with PsA completed the Portuguese PsAQoL on two occasions, 2 weeks apart. A larger sample was recruited to determine internal consistency and construct validity. The Nottingham Health Profile (NHP) was used as a comparator instrument. Translation and adaptation were successful. Cronbach´s alpha for the Portuguese version of the PsAQoL was 0.91 and the test-retest reliability was 0.93. The PsAQoL could distinguish between groups of patients defined by self-reported general health status, self-reported severity of PsA and flare of arthritis. There was a positive correlation between the total score of the PsAQoL and each of the sections of the NHP. The Portuguese version of the PsAQoL was found to be relevant, understandable and easy to complete, reliable and valid.

An in-vitro evaluation of mechanical and esthetic properties of orthodontic sealants

PubMed Central

Premaraj, Thyagaseely Sheela; Rohani, Nima; Covey, David; Premaraj, Sundaralingam; Hua, Yi; Watanabe, Hidehiko

2014-01-01

Objective: To evaluate mechanical and esthetic Properties of two commercially available orthodontic sealants: Opal®Seal (OS) and L.E.D. Pro Seal (PS). Materials and Methods: Discs of each sealant were prepared to test the following properties: Micro hardness, wear resistance and color stability. Samples were randomly selected after the wear test for SEM imaging to analyze surface morphology. Results: OS was significantly harder than PS (P < 0.001). PS was significantly more wear resistant than OS (P < 0.05). PS showed a greater ∆E*ab (increased staining) when placed in wine or coffee showing a significant difference (P < 0.05). SEM showed particle size, shape and distribution were different for PS and OS reflecting the pattern seen on wear surfaces. Conclusion: Both orthodontic sealants are beneficial for protecting enamel. However with better wear properties PS was superior in resisting mechanical stresses. OS was more color stable. PMID:25512729

Optimizing concentration of shifter additive for plastic scintillators of different size

NASA Astrophysics Data System (ADS)

Adadurov, A. F.; Zhmurin, P. N.; Lebedev, V. N.; Titskaya, V. D.

2009-02-01

This paper concerns the influence of wavelength shifting (secondary) luminescent additive (LA 2) on the light yield of polystyrene-based plastic scintillator (PS) taking self-absorption into account. Calculations of light yield dependence on concentration of 1.4-bis(2-(5-phenyloxazolyl)-benzene (POPOP) as LA 2 were made for various path lengths of photons in PS. It is shown that there is an optimal POPOP concentration ( Copt), which provides a maximum light yield for a given path length. This optimal concentration is determined by the competition of luminescence and self-reflection processes. Copt values were calculated for PS of different dimensions. For small PS, Copt≈0.02%, which agree with a common (standard) value of POPOP concentration. For higher PS dimensions, the optimal POPOP concentration is decreased (to Copt≈0.006% for 320×30×2 cm sample), reducing the light yield from PS by almost 35%.

Mesoscale variation in the photophysiology of the reef building coral Pocillopora damicornis along an environmental gradient

NASA Astrophysics Data System (ADS)

Cooper, Timothy F.; Ulstrup, Karin E.

2009-06-01

Spatial variation in the photophysiology of symbiotic dinoflagellates (zooxanthellae) of the scleractinian coral Pocillopora damicornis was examined along an environmental gradient in the Whitsunday Islands (Great Barrier Reef) at two depths (3 m and 6 m). Chlorophyll a fluorescence of photosystem II (PSII) and PAR-absorptivity measurements were conducted using an Imaging-PAM (pulse-amplitude-modulation) fluorometer. Most photophysiological parameters correlated with changes in environmental conditions quantified by differences in water quality along the gradient. For example, maximum quantum yield ( Fv/ Fm) increased and PAR-absorptivity decreased as water quality improved along the gradient from nearshore reefs (low irradiance, elevated nutrients and sediments) to outer islands (high irradiance, low nutrients and sediments). For apparent photosynthetic rate (PS max) and minimum saturating irradiance ( Ek), the direction of change differed depending on sampling depth, suggesting that different mechanisms of photo-acclimatisation operated between shallow and deep corals. Deep corals conformed to typical patterns of light/shade acclimatisation whereas shallow corals exhibited reduced PS max and Ek with improving water quality coinciding with greater heat dissipation (NPQ 241). Furthermore, deep corals on nearshore reefs exhibited elevated Q241 in comparison to outer islands possibly due to effects of sedimentation and/or pollutants rather than irradiance. These results highlight the importance of mesoscale sampling to obtain useful estimates of the variability of photophysiological parameters, particularly if such measures are to be used as bioindicators of the condition of coral reefs.

Solid-Phase Fe Speciation along the Vertical Redox Gradients in Floodplains using XAS and Mössbauer Spectroscopies.

PubMed

Chen, Chunmei; Kukkadapu, Ravi K; Lazareva, Olesya; Sparks, Donald L

2017-07-18

Properties of Fe minerals are poorly understood in natural soils and sediments with variable redox conditions. In this study, we combined 57 Fe Mössbauer and Fe K-edge X-ray absorption spectroscopic (XAS) techniques to assess solid-phase Fe speciation along the vertical redox gradients of floodplains, which exhibited a succession of oxic, anoxic, and suboxic-oxic zones with increasing depth along the vertical profiles. The incised stream channel is bounded on the east by a narrow floodplain and a steep hillslope, and on the west by a broad floodplain. In the eastern floodplain, the anoxic conditions at the intermediate horizon (55-80 cm) coincided with lower Fe(III)-oxides (particularly ferrihydrite), in concurrence with a greater reduction of phyllosilicates(PS)-Fe(III) to PS-Fe(II), relative to the oxic near-surface and sandy gravel layers. In addition, the anoxic conditions in the eastern floodplain coincided with increased crystallinity of goethite, relative to the oxic layers. In the most reduced intermediate sediments at 80-120 cm of the western floodplain, no Fe(III)-oxides were detected, concurrent with the greatest PS-Fe(III) reduction (PS-Fe(II)/Fe(III) ratio ≈ 1.2 (Mössbauer) or 0.8 (XAS)). In both oxic near-surface horizon and oxic-suboxic gravel aquifers beneath the soil horizons, Fe(III)-oxides were mainly present as ferrihydrite with a much less amount of goethite, which preferentially occurred as nanogoethite or Al/Si-substituted goethite. Ferrihydrite with varying crystallinity or impurities such as organic matter, Al or Si, persisted under suboxic-oxic conditions in the floodplain. This study indicates that vertical redox gradients exert a major control on the quantity and speciation of Fe(III) oxides as well as the oxidation state of structural Fe in PS, which could significantly affect nutrient cycling and carbon (de)stabilization.

The gray area between synapse structure and function-Gray's synapse types I and II revisited.

PubMed

Klemann, Cornelius J H M; Roubos, Eric W

2011-11-01

On the basis of ultrastructural parameters, the concept was formulated that asymmetric Type I and symmetric Type II synapses are excitatory and inhibitory, respectively. This "functional Gray synapses concept" received strong support from the demonstration of the excitatory neurotransmitter glutamate in Type I synapses and of the inhibitory neurotransmitter γ-aminobutyric acid in Type II synapses, and is still frequently used in modern literature. However, morphological and functional evidence has accumulated that the concept is less tenable. Typical features of synapses like shape and size of presynaptic vesicles and synaptic cleft and presence of a postsynaptic density (PsD) do not always fit the postulated (excitatory/inhibitory) function of Gray's synapses. Furthermore, synapse function depends on postsynaptic receptors and associated signal transduction mechanisms rather than on presynaptic morphology and neurotransmitter type. Moreover, the notion that many synapses are difficult to classify as either asymmetric or symmetric has cast doubt on the assumption that the presence of a PsD is a sign of excitatory synaptic transmission. In view of the morphological similarities of the PsD in asymmetric synapses with membrane junctional structures such as the zonula adherens and the desmosome, asymmetric synapses may play a role as links between the postsynaptic and presynaptic membrane, thus ensuring long-term maintenance of interneuronal communication. Symmetric synapses, on the other hand, might be sites of transient communication as takes place during development, learning, memory formation, and pathogenesis of brain disorders. Confirmation of this idea might help to return the functional Gray synapse concept its central place in neuroscience. Copyright © 2011 Wiley-Liss, Inc.

Preparation and application of a molecular capture for safety detection of cosmetics based on surface imprinting and multi-walled carbon nanotubes.

PubMed

Wang, Fang; Li, Xiaoyan; Li, Junjie; Zhu, Chen; Liu, Min; Wu, Zongyuan; Liu, Li; Tan, Xuecai; Lei, Fuhou

2018-05-14

A novel composite material for prednisone molecular capture (PS-MC) was prepared by surface imprinting technique in combination with a polyethylene filter plate coated with multi-walled carbon nanotubes for the first time. PS-MC was achieved by using prednisone as the template molecule, 3-aminopropyltriethoxysilane as the monomer, and tetraethoxysilane as the cross-linker. The structure, morphology, and thermal stability of the prepared PS-MC were studied by fourier-transform infrared spectrometry, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and thermogravimetric analysis. PS-MC was assessed by re-binding experiments such as adsorption kinetics, adsorption isotherms, molecular identification, and applied to the separation and enrichment of prednisone in cosmetics. The results indicated that PS-MC has rapid binding kinetic, high adsorption capacity, and favorable reusability. The imprinted materials were coupled with HPLC to selectively separation, purification, and detection of prednisone from spiked cosmetic samples. The recoveries of spiked cosmetic samples were in the range of 83.0-106.0%, with relative standard deviations of less than 2.10%, and the limit of detection of 5 ng/mL (S/N = 3). Copyright © 2018. Published by Elsevier Inc.

Opto-chemical response of CR-39 and polystyrene to swift heavy ion irradiation

NASA Astrophysics Data System (ADS)

Singh, Lakhwant; Singh Samra, Kawaljeet; Singh, Ravinder

2007-02-01

The samples of CR-39 and polystyrene (PS) polymers have been irradiated with 64Cu 9+ (120 MeV) and 12C 5+ (70 MeV) ion beams having fluence ranging from 1 × 10 11 to 1 × 10 13 ions/cm -2. UV spectra of irradiated samples reveal that the optical band gap decreases from 5.50 to 2.75 eV in CR-39 and from 4.36 to 1.73 eV in PS. The correlation between optical band gap and the number of carbon atoms in a cluster with modified Tauc's equation has been discussed in case of CR-39. FTIR spectra reveal that there is the formation of hydroxyl, alkene, alkyne and carboxylic groups in the Cu-ion irradiated PS. In CR-39, changes in the intensity of the bands on irradiation relative to pristine samples without appearance of any new band have been observed and discussed.

Electrospun polystyrene/oxidized carbon nanotubes film as both sorbent for thin film microextraction and matrix for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

PubMed

He, Xiao-Mei; Zhu, Gang-Tian; Yin, Jia; Zhao, Qin; Yuan, Bi-Feng; Feng, Yu-Qi

2014-07-18

In the current study, polystyrene/oxidized carbon nanotubes (PS/OCNTs) film was prepared and applied as both an adsorbent of thin film microextraction (TFME) and matrix for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for the first time. The uniform size of PS/OCNTs film with OCNTs evenly and firmly immobilized in PS was obtained by electrospinning. And a novel TFME device was developed using the prepared PS/OCNTs film to enrich benzo[a]pyrene (BaP) from water, and also BaP and 1-hydroxypyrene (1-OHP) from urine sample. Then the extracted analytes on the PS/OCNTs film were directly applied to MALDI-MS analysis with PS/OCNTs film as the MALDI matrix. Our results show that PS/OCNTs film is a good TFME adsorbent toward the analytes and an excellent matrix for the sensitive determination of BaP and 1-OHP using MALDI-TOF-MS. The employment of PS/OCNTs as the matrix for MALDI can effectively avoid the large variation of signal intensity normally resulting from heterogeneous distribution of the adsorbed analyte on matrix layer, which therefore significantly improve spot-to-spot reproducibility. The introduction of PS in the film can prevent OCNTs from flying out of MALDI plate to damage the equipment. In addition, PS/OCNTs film also largely extended the duration of ion signal of target analyte compared to OCNTs matrix. The developed method was further successfully used to quantitatively determine BaP in environmental water and 1-OHP in urine samples. The results show that BaP and 1-OHP could be easily detected at concentrations of 50pgmL(-1) and 500pgmL(-1), respectively, indicating the high detection sensitivity of this method. For BaP analysis, the linear range was 0.1-20ngmL(-1) with a correlation coefficient of 0.9970 and the recoveries were in the range of 81.3 to 123.4% with the RSD≤8.5% (n=3); for urinary 1-OHP analysis, the linear range was 0.5-20ngmL(-1) with a correlation coefficient of 0.9937 and the recoveries were in the range of 79.2 to 103.4% with the RSD≤7.6% (n=3). Taken together, the developed method provides a simple, rapid, cost-effective and high-throughput approach for the analysis of BaP in environmental water and endogenous 1-OHP in urine samples. Copyright © 2014 Elsevier B.V. All rights reserved.

In situ photoacoustic characterization for porous silicon growing: Detection principles

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

Ramirez-Gutierrez, C. F.; Licenciatura en Ingeniería Física, Facultad de Ingeniería, Universidad Autónoma de Querétaro, C. P. 76010 Querétaro, Qro.; Castaño-Yepes, J. D.

There are a few methodologies for monitoring the in-situ formation of Porous Silicon (PS). One of the methodologies is photoacoustic. Previous works that reported the use of photoacoustic to study the PS formation do not provide the physical explanation of the origin of the signal. In this paper, a physical explanation of the origin of the photoacoustic signal during the PS etching is provided. The incident modulated radiation and changes in the reflectance are taken as thermal sources. In this paper, a useful methodology is proposed to determine the etching rate, porosity, and refractive index of a PS film bymore » the determination of the sample thickness, using scanning electron microscopy images. This method was developed by carrying out two different experiments using the same anodization conditions. The first experiment consisted of growth of the samples with different etching times to prove the periodicity of the photoacoustic signal, while the second one considered the growth samples using three different wavelengths that are correlated with the period of the photoacoustic signal. The last experiment showed that the period of the photoacoustic signal is proportional to the laser wavelength.« less

Ultra-high resolution, polarization sensitive transversal optical coherence tomography for structural analysis and strain mapping

NASA Astrophysics Data System (ADS)

Wiesauer, Karin; Pircher, Michael; Goetzinger, Erich; Hitzenberger, Christoph K.; Engelke, Rainer; Ahrens, Gisela; Pfeiffer, Karl; Ostrzinski, Ute; Gruetzner, Gabi; Oster, Reinhold; Stifter, David

2006-02-01

Optical coherence tomography (OCT) is a contactless and non-invasive technique nearly exclusively applied for bio-medical imaging of tissues. Besides the internal structure, additionally strains within the sample can be mapped when OCT is performed in a polarization sensitive (PS) way. In this work, we demonstrate the benefits of PS-OCT imaging for non-biological applications. We have developed the OCT technique beyond the state-of-the-art: based on transversal ultra-high resolution (UHR-)OCT, where an axial resolution below 2 μm within materials is obtained using a femtosecond laser as light source, we have modified the setup for polarization sensitive measurements (transversal UHR-PS-OCT). We perform structural analysis and strain mapping for different types of samples: for a highly strained elastomer specimen we demonstrate the necessity of UHR-imaging. Furthermore, we investigate epoxy waveguide structures, photoresist moulds for the fabrication of micro-electromechanical parts (MEMS), and the glass-fibre composite outer shell of helicopter rotor blades where cracks are present. For these examples, transversal scanning UHR-PS-OCT is shown to provide important information about the structural properties and the strain distribution within the samples.

Positron Annihilation Spectroscopy during physical aging of carbon-black filled rubber composites

NASA Astrophysics Data System (ADS)

Jobando, Vincent; Wang, Jingyi; Quarles, C. A.

2004-10-01

We have used positron annihilation spectroscopy to investigate the relaxation behavior of vulcanized and un-vulcanized rubber-carbon black composites. The samples were studied at temperatures above their glassy transitions. Changes in o-Ps intensity and S-parameter are indicative of the structural relaxation process. We have found that at room temperature, both vulcanized and un-vulcanized rubber showed no changes after ageing for about two months. While within the same period, un-vulcanized samples heated at 60^oC and allowed to age at room -temperature showed a decrease in o-Ps intensity and S-parameter. The o-Ps lifetime also decreased after this heat treatment for the un-vulcanized samples while the vulcanized ones remained unchanged. The changes seen were reversible however when we stopped heating the samples. We proposed that heat disordered the system and on cooling, rubber molecules formed more ordered regions, which we interpreted as crystallization. Vulcanized samples remained unchanged. We also found out that free volume decreases during physical deformation of pure rubber, but rubber with carbon black showed a significant rise in free volume. The lifetimes however remained unchanged.

Elastomeric Negative Acoustic Contrast Particles for Affinity Capture Assays

PubMed Central

Cushing, Kevin W.; Piyasena, Menake E.; Carroll, Nick J.; Maestas, Gian C.; López, Beth Ann; Edwards, Bruce S.; Graves, Steven W.; López, Gabriel P.

2013-01-01

This report describes the development of elastomeric capture microparticles (ECμPs) and their use with acoustophoretic separation to perform microparticle assays via flow cytometry. We have developed simple methods to form ECμPsby crosslinking droplets of common commercially available silicone precursors in suspension followed by surface functionalization with biomolecular recognition reagents. The ECμPs are compressible particles that exhibit negative acoustic contrast in ultrasound when suspended in aqueous media, blood serum or diluted blood. In this study, these particles have been functionalized with antibodies to bind prostate specific antigen and immunoglobulin (IgG). Specific separation of the ECμPs from blood cells is achieved by flowing them through a microfluidic acoustophoretic device that uses an ultrasonic standing wave to align the blood cells, which exhibit positive acoustic contrast, at a node in the acoustic pressure distribution while aligning the negative acoustic contrast ECμPs at the antinodes. Laminar flow of the separated particles to downstream collection ports allows for collection of the separated negative contrast (ECμPs) and positive contrast particles (cells). Separated ECμPs were analyzed via flow cytometry to demonstrate nanomolar detection for prostate specific antigen in aqueous buffer and picomolar detection for IgG in plasma and diluted blood samples. This approach has potential applications in the development of rapid assays that detect the presence of low concentrations of biomarkers in a number of biological sample types. PMID:23331264

Shelf-life extension of Pacific white shrimp using algae extracts during refrigerated storage.

PubMed

Li, Yingchang; Yang, Zhongyan; Li, Jianrong

2017-01-01

Shrimp is a low-fat, high-protein aquatic product, and is susceptible to spoilage during storage. To establish an effective method for the quality control of Pacific white shrimp, the effects of polyphenols (PP) and polysaccharides (PS) from Porphyra yezoensis on the quality of Pacific white shrimp were assessed during refrigerated storage. Pacific white shrimp samples were treated with 5 g L -1 polyphenols, and 8 g L -1 polysaccharides, then stored at 4 ± 1 °C for 8 days. All samples were subjected to measurement of total viable count (TVC), pH, total volatile basic nitrogen (TVB-N), K-value, thiobarbituric acid (TBA), polyphenol oxidase (PPO) activity, and were also assessed by sensory evaluation. The results showed that PP, PS, and the mixture of polyphenols and polysaccharides (PP+PS) could inhibit the increase of total volatile basic nitrogen (TVB-N), thiobarbituric acid (TBA) and K-value, and reduce total viable count (TVC) compared with the control group. PP could also inhibit polyphenol oxidase (PPO) activity. Sensory evaluation proved the efficacy of PP and PS by maintaining the overall quality of Pacific white shrimp during refrigerated storage. Moreover, PP+PS could extend the shelf-life of shrimp by 3-4 days compared with the control group. PP+PS could more effectively maintain quality and extend shelf-life during refrigerated storage. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

A Test of the Empirical Profile and Coherence of the DSM-5 Psychopathy Specifier.

PubMed

Miller, Joshua D; Lamkin, Joanna; Maples-Keller, Jessica L; Sleep, Chelsea E; Lynam, Donald R

2017-11-13

The Diagnostic and Statistical Manual of Mental Disorders-5th edition (DSM-5; American Psychiatric Association, 2013) introduced a psychopathy specifier (DSM-5 PS) as part of the Section III diagnostic model of antisocial personality disorder. Designed to capture the construct of fearless dominance/boldness, the DSM-5 PS is assessed on the basis of the presence of low scores on traits of withdrawal and anxiousness, and high scores on attention seeking. These constructs have garnered attention in the past decade but are the subject of substantial debate as to their role in the conceptualization and assessment of psychopathy, given their limited relations to the maladaptive outcomes typically associated with this personality disorder. In the current study (N = 340 undergraduates; 170 informants), we examined the DSM-5 PS, both in composite form and its trait subscales, to investigate the degree to which the DSM-5 PS manifested empirical profiles associated with psychopathy and its maladaptive correlates. Consistent with prior fearless dominance/boldness research, the DSM-5 PS manifested limited relations with other components of psychopathy, symptoms of DSM-5 Section II and III antisocial personality disorder, and self- and informant-related impairment scores. When examined at the individual subscale level, the 3 DSM-5 PS subscales manifested only partially overlapping profiles and only 1 of the 3-Attention Seeking-demonstrated an association with maladaptivity (e.g., externalizing behaviors). These findings raise important concerns about the coherence and utility of the DSM-5 PS as a diagnostic specifier included in a psychiatric nosology. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Hexameric oligomerization of mitochondrial peroxiredoxin PrxIIF and formation of an ultrahigh affinity complex with its electron donor thioredoxin Trx-o.

PubMed

Barranco-Medina, Sergio; Krell, Tino; Bernier-Villamor, Laura; Sevilla, Francisca; Lázaro, Juan-José; Dietz, Karl-Josef

2008-01-01

Mitochondria from plants, yeast, and animals each contain at least one peroxiredoxin (Prx) that is involved in peroxide detoxification and redox signalling. The supramolecular dynamics of atypical type II Prx targeted to the mitochondrion was addressed in pea. Microcalorimetric (ITC) titrations identified an extremely high-affinity binding between the mitochondrial PsPrxIIF and Trx-o with a K(D) of 126+/-14 pM. Binding was driven by a favourable enthalpy change (DeltaH= -60.6 kcal mol(-1)) which was counterbalanced by unfavourable entropy changes (TDeltaS= -47.1 kcal mol(-1)). This is consistent with the occurrence of large conformational changes during binding which was abolished upon site-directed mutaganesis of the catalytic C59S and C84S. The redox-dependent interaction was confirmed by gel filtration of mitochondrial extracts and co-immunoprecipitation from extracts. The heterocomplex of PsPrxIIF and Trx-o reduced peroxide substrates more efficiently than free PsPrxIIF suggesting that Trx-o serves as an efficient and specific electron donor to PsPrxIIF in vivo. Other Trx-s tested by ITC analysis failed to interact with PsPrxIIF indicating a specific recognition of PsPrxIIF by Trx-o. PsPrxIIF exists primarily as a dimer or a hexamer depending on the redox state. In addition to the well-characterized oligomerization of classical 2-Cys Prx the results also show that atypical Prx undergo large structural reorganization with implications for protein-protein interaction and function.

High-Affinity Interactions of Beryllium(2+) with Phosphatidylserine Result in a Cross-Linking Effect Reducing Surface Recognition of the Lipid.

PubMed

Ermakov, Yuri A; Kamaraju, Kishore; Dunina-Barkovskaya, Antonina; Vishnyakova, Khava S; Yegorov, Yegor E; Anishkin, Andriy; Sukharev, Sergei

2017-10-10

Beryllium has multiple industrial applications, but its manufacture is associated with a serious occupational risk of developing chronic inflammation in the lungs known as berylliosis, or chronic beryllium disease. Although the Be 2+ -induced abnormal immune responses have recently been linked to a specific MHC-II allele, the nature of long-lasting granulomas is not fully understood. Here we show that Be 2+ binds with a micromolar affinity to phosphatidylserine (PS), the major surface marker of apoptotic cells. Isothermal titration calorimetry indicates that, like that of Ca 2+ , binding of Be 2+ to PS liposomes is largely entropically driven, likely by massive desolvation. Be 2+ exerts a compacting effect on PS monolayers, suggesting cross-linking through coordination by both phosphates and carboxyls in multiple configurations, which were visualized in molecular dynamics simulations. Electrostatic modification of PS membranes by Be 2+ includes complete neutralization of surface charges at ∼30 μM, accompanied by an increase in the boundary dipole potential. The data suggest that Be 2+ can displace Ca 2+ from the surface of PS, and being coordinated in a tight shell of four oxygens, it can mask headgroups from Ca 2+ -mediated recognition by PS receptors. Indeed, 48 μM Be 2+ added to IC-21 cultured macrophages specifically suppresses binding and engulfment of PS-coated silica beads or aged erythrocytes. We propose that Be 2+ adsorption at the surface of apoptotic cells may potentially prevent normal phagocytosis, thus causing accumulation of secondary necrotic foci and the resulting chronic inflammation.

Photoelectrocatalytic reduction of CO2 to methanol over a photosystem II-enhanced Cu foam/Si-nanowire system.

PubMed

Lian, Zichao; Pan, Donglai; Wang, Wenchao; Zhang, Dieqing; Li, Guisheng; Li, Hexing

2017-10-01

A solar-light double illumination photoelectrocatalytic cell (SLDIPEC) was fabricated for autonomous CO 2 reduction and O 2 evolution with the aid of photosystem II (PS-II, an efficient light-driven water-oxidized enzyme from nature) and utilized in a photoanode solution. The proposed SLPEC system was composed of Cu foam as the photoanode and p-Si nanowires (Si-NW) as the photocathode. Under solar irradiation, it exhibited a super-photoelectrocatalytic performance for CO 2 conversion to methanol, with a high evolution rate (41.94mmol/hr), owing to fast electron transfer from PS-II to Cu foam. Electrons were subsequently trapped by Si-NW through an external circuit via bias voltage (0.5V), and a suitable conduction band potential of Si (-0.6eV) allowed CO 2 to be easily reduced to CH 3 OH at the photocathode. The constructed Z-scheme between Cu foam and Si-NW can allow the SLDIPEC system to reduce CO 2 (8.03mmol/hr) in the absence of bias voltage. This approach makes full use of the energy band mismatch of the photoanode and photocathode to design a highly efficient device for solving environmental issues and producing clean energy. Copyright © 2017. Published by Elsevier B.V.

Overlapping Residual Herbicides for Control of Photosystem (PS) II- and 4-Hydroxyphenylpyruvate Dioxygenase (HPPD)-Inhibitor-Resistant Palmer amaranth (Amaranthus palmeri S. Watson) in Glyphosate-Resistant Maize

PubMed Central

Chahal, Parminder S.; Ganie, Zahoor A.; Jhala, Amit J.

2018-01-01

A Palmer amaranth (Amaranthus palmeri S. Watson) biotype has evolved resistance to photosystem (PS) II- (atrazine) and 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides (mesotrione, tembotrione, and topramezone) in maize seed production field in Nebraska, USA. The objectives of this study were to determine the effect of soil residual pre-emergence (PRE) herbicides followed by (fb) tank-mixture of residual and foliar active post-emergence (POST) herbicides on PS-II- and HPPD-inhibitor-resistant Palmer amaranth control, maize yield, and net economic returns. Field experiments were conducted in a grower's field infested with PS II- and HPPD-inhibitor-resistant Palmer amaranth near Shickley in Fillmore County, Nebraska, USA in 2015 and 2016. The contrast analysis suggested that saflufenacil plus dimethenamid-P or pyroxasulfone plus saflufenacil applied PRE provided 80–82% Palmer amaranth control compared to 65 and 39% control with saflufenacil and pyroxasulfone applied alone at 3 weeks after PRE (WAPRE), respectively. Among the PRE fb POST herbicide programs, 95–98% Palmer amaranth control was achieved with pyroxasulfone plus safluefenacil, or saflufenacil plus dimethenamid-P applied PRE, fb glyphosate plus topramezone plus dimethenamid-P plus atrazine, glyphosate plus diflufenzopyr plus dicamba plus pyroxasulfone, glyphosate plus diflufenzopyr plus pendimethalin, or glyphosate plus diflufenzopyr plus dicamba plus atrazine applied POST at 3 weeks after POST (WAPOST) through maize harvest. Based on contrast analysis, PRE fb POST programs provided 77–83% Palmer amaranth control at 3 WAPOST through maize harvest compared to 12–15% control with PRE-only and 66–84% control with POST-only programs. Similarly, PRE fb POST programs provided 99% biomass reduction at 6 WAPOST compared to PRE-only (28%) and POST-only (87%) programs. PRE fb POST programs provided higher maize yield (13,617 kg ha−1) and net return (US $1,724 ha−1) compared to the PRE-only (2,656 kg ha−1; US $285 ha−1) and POST-only (11,429 kg ha−1; US $1,539 ha−1) programs. The results indicated that effective control of multiple herbicide-resistant Palmer amaranth can be achieved with PRE fb POST programs that include herbicides with overlapping residual activity to maintain season-long control. PMID:29375605

Tsunami Evidence in South Coast Java, Case Study: Tsunami Deposit along South Coast of Cilacap

NASA Astrophysics Data System (ADS)

Rizal, Yan; Aswan; Zaim, Yahdi; Dwijo Santoso, Wahyu; Rochim, Nur; Daryono; Dewi Anugrah, Suci; Wijayanto; Gunawan, Indra; Yatimantoro, Tatok; Hidayanti; Herdiyani Rahayu, Resti; Priyobudi

2017-06-01

Cilacap Area is situated in coastal area of Southern Java and directly affected by tsunami hazard in 2006. This event was triggered by active subduction in Java Trench which active since long time ago. To detect tsunami and active tectonic in Southern Java, paleo-tsunami study is performed which is targeted paleo-tsunami deposit older than fifty years ago. During 2011 - 2016, 16 locations which suspected as paleo-tsunami location were visited and the test-pits were performed to obtain characteristic and stratigraphy of paleo-tsunami layers. Paleo-tsunami layer was identified by the presence of light-sand in the upper part of paleo-soil, liquefaction fine grain sandstone, and many rip-up clast of mudstone. The systematic samples were taken and analysis (micro-fauna, grainsize and dating analysis). Micro-fauna result shows that paleo-tsunami layer consist of benthonic foraminifera assemblages from different bathymetry and mixing in one layer. Moreover, grainsize shows random grain distribution which characterized as turbulence and strong wave deposit. Paleo-tsunami layers in Cilacap area are correlated using paleo-soil as marker. There are three paleo-tsunami layers and the distribution can be identified as PS-A, PS-B and PS-C. The samples which were taken in Glempang Pasir layer are being dated using Pb - Zn (Lead-Zinc) method. The result of Pb - Zn (Lead-Zinc) dating shows that PS-A was deposited in 139 years ago, PS-B in 21 years ago, and PS C in 10 years ago. This result indicates that PS -1 occurred in 1883 earthquake activity while PS B formed in 1982 earthquake and PS-C was formed by 2006 earthquake. For ongoing research, the older paleo-tsunami layers were determined in the Gua Nagaraja, close to Selok location and 6 layers of Paleo-tsunami suspect found which shown a similar characteristic with the layers from another location. The three layers deeper approximately have an older age than another location in Cilacap.

2-Aminoacetophenone as a potential breath biomarker for Pseudomonas aeruginosa in the cystic fibrosis lung

PubMed Central

2010-01-01

Background Pseudomonas aeruginosa infections are associated with progressive life threatening decline of lung function in cystic fibrosis sufferers. Growth of Ps. aeruginosa releases a "grape-like" odour that has been identified as the microbial volatile organic compound 2-aminoacetophenone (2-AA). Methods We investigated 2-AA for its specificity to Ps. aeruginosa and its suitability as a potential breath biomarker of colonisation or infection by Solid Phase Micro Extraction and Gas Chromatography-Mass Spectrometry (GC/MS). Results Cultures of 20 clinical strains of Ps. aeruginosa but not other respiratory pathogens had high concentrations of 2-AA in the head space of in vitro cultures when analysed by GC/MS. 2-AA was stable for 6 hours in deactivated glass sampling bulbs but was not stable in Tedlar® bags. Optimisation of GC/MS allowed detection levels of 2-AA to low pico mol/mol range in breath. The 2-AA was detected in a significantly higher proportion of subjects colonised with Ps. aeruginosa 15/16 (93.7%) than both the healthy controls 5/17 (29%) (p < 0.0002) and CF patients not colonised with Ps. aeruginosa 4/13(30.7%) (p < 0.001). The sensitivity and specificity of the 2-AA breath test compared to isolation of Ps. aeruginosa in sputum and/or BALF was 93.8% (95% CI, 67-99) and 69.2% (95% CI, 38-89) respectively. The peak integration values for 2-AA analysis in the breath samples were significantly higher in Ps. aeruginosa colonised subjects (median 242, range 0-1243) than the healthy controls (median 0, range 0-161; p < 0.001) and CF subjects not colonised with Ps. aeruginosa (median 0, range 0-287; p < 0.003) Conclusions Our results report 2-AA as a promising breath biomarker for the detection of Ps. aeruginosa infections in the cystic fibrosis lung. PMID:21054900

Bacterial Bolsheviks: PS II and the Evolution of the Oxygenic Revolution

NASA Astrophysics Data System (ADS)

Kopp, R. E.; Kirschvink, J. L.; Newman, D. K.; Nash, C. Z.; Hilburn, I. A.

2003-12-01

After the rise of life itself, the most radical transformation of Earth's biogeochemical cycles was the transition from an anoxic to an oxic world. Though various studies have suggested O2 made its first bulk appearance in the atmosphere some time between 3.8 and 2.1 Ga, virtually all analyses agree the production of large quantities of free O2 was triggered by the evolution of oxygenic photosynthesis. We suggest the oldest strong geological evidence for O2 is the 2.22 Ga Kalahari Mn member of the Hotazel BIF (1), as in the oceans only free O2 can oxidize soluble Mn(II) into insoluble Mn(IV). Some have argued, however, that oxygenic cyanobacteria had originated by 2.7 Ga. The ˜500 Myr "gap" has often been interpreted as the timescale for gradual evolutionary improvement of the O2-generating system. Biochemical and genomic analyses of photosynthetic bacteria indicate that photosystems I and II, which operate together in cyanobacteria, had a long history of parallel development. Green sulfur bacteria and heliobacteria use PS-II, while green non-sulfur and purple bacteria use PS-I; none can use H2O as an electron donor. Recent genetic analyses show lateral gene transfer was rampant among photosynthetic lineages (2). Moreover, extant cyanobacteria shut down PS-II in the presence of an alternative electron donor like H2S. This suggests PS-I and PS-II came together with their functions intact. Hence, most `debugging' of the two systems predates their merger in the ancestor of modern cyanobacteria. The time interval between the lateral transfer events and the evolution of oxygenic photosynthesis could thus have been geologically short. We suggest the ˜500 Myr "gap" may result from misinterpretations. The presence of oxygenic photosynthesis is uncertain before the deposition of the Hotazel formation, in the aftermath of the Makganyene glaciation (1). A simple model of nutrient and reductant fluxes argues that, once triggered, the oxygenation of a reducing surface environment warmed by a CH4 greenhouse (3) should occur fairly rapidly, within ˜ 10 My. The trigger requires both the evolution of cyanobacteria and sufficiently high nutrient (mainly P) fluxes to allow O2 production to overwhelm reductant fluxes. P flux into the oceans in glaciated worlds correlates with increased continental weathering during glacial intervals (4). Thus, were cyanobacteria present during the Huronian glaciations, which predate 2.22 Ga (5), these glaciations should have triggered the oxygenation event. Instead, the oxygenation event seems to correlate with the Makganyene glaciation, at 2.22 Ga (6). The appearance of red beds in the Upper Timeball Hill formation directly underlying the Makganyene diamictite supports this interpretation. As would be expected from a glaciation associated with the destruction of a CH4 greenhouse, paleomagnetic data indicate the Makganyene glaciation was a global Snowball event (7). Cyanobacteria appear to have evolved in the short interval between the Huronian glaciations and the Makganyene glaciation. The lengthy delay between the earliest life on Earth and the appearance of cyanobacteria suggests that the oxygenic revolution was a fairly low probability event; planets with oxygenic biospheres may be quite rare. 1. J. L. Kirschvink et al., PNAS 97, 1400-1405 (2000). 2. J. Raymond et al., Science 298, 1616-1620 (2002). 3. A. A. Pavlov et al., JGR 105, 11981-11990 (2000). 4. K. B. F”llmi, Geology 23, 503-506 (1995). 5. S. R. Noble, P. C. Lightfoot, Can. J. Earth Sci. 29, 1424-1429 (1992). 6. D. H. Cornell et al., Precamb. Res. 79, 101-123 (1996). 7. D. A. Evans et al., Nature 386, 262-266 (1997).

Interfacial charge separation and recombination in InP and quasi-type II InP/CdS core/shell quantum dot-molecular acceptor complexes.

PubMed

Wu, Kaifeng; Song, Nianhui; Liu, Zheng; Zhu, Haiming; Rodríguez-Córdoba, William; Lian, Tianquan

2013-08-15

Recent studies of group II-VI colloidal semiconductor heterostuctures, such as CdSe/CdS core/shell quantum dots (QDs) or dot-in-rod nanorods, show that type II and quasi-type II band alignment can facilitate electron transfer and slow down charge recombination in QD-molecular electron acceptor complexes. To explore the general applicability of this wave function engineering approach for controlling charge transfer properties, we investigate exciton relaxation and dissociation dynamics in InP (a group III-V semiconductor) and InP/CdS core/shell (a heterostructure beween group III-V and II-VI semiconductors) QDs by transient absorption spectroscopy. We show that InP/CdS QDs exhibit a quasi-type II band alignment with the 1S electron delocalized throughout the core and shell and the 1S hole confined in the InP core. In InP-methylviologen (MV(2+)) complexes, excitons in the QD can be dissociated by ultrafast electron transfer to MV(2+) from the 1S electron level (with an average time constant of 11.4 ps) as well as 1P and higher electron levels (with a time constant of 0.39 ps), which is followed by charge recombination to regenerate the complex in its ground state (with an average time constant of 47.1 ns). In comparison, InP/CdS-MV(2+) complexes show similar ultrafast charge separation and 5-fold slower charge recombination rates, consistent with the quasi-type II band alignment in these heterostructures. This result demonstrates that wave function engineering in nanoheterostructures of group III-V and II-VI semiconductors provides a promising approach for optimizing their light harvesting and charge separation for solar energy conversion applications.

Nonlinear mirror modelocking of a bounce geometry laser.

PubMed

Thomas, G M; Bäuerle, A; Farrell, D J; Damzen, M J

2010-06-07

We present the investigation of nonlinear mirror modelocking (NLM) of a bounce amplifier laser. This technique, a potential rival to SESAM modelocking, uses a nonlinear crystal and a dichroic mirror to passively modelock a Nd:GdVO(4) slab bounce amplifier operating at 1063nm. At 11.3W, we present the highest power achieved using the NLM technique, using type-II phase-matched KTP, with a pulse duration of 57ps. Using type-I phase-matched BiBO, modelocking was achieved with a shorter pulse duration of 5.7ps at an average power of 7.1W.

Command Flight Path Display. Phase I and II.

DTIC Science & Technology

1983-09-01

transmissions over the standard 56K baud interface. The PS-300 was a commercial unit and required some modifications to ensure its reliability in an...1 H7750-AA Battery Backup NADC 5 Oct E2 9 1 LA-12D Decwriter SAI/RtS 4 11ov 82 10 1 BC03M-25 Null Modem Cable SAI/RM0S 4 Nov 82 35 2 ~%*~’ .5°’ 11 1...of about 1200 baud. (The interface hardware is capable of 56K baud transmission, but the standard PS-300 firmware is only able to process input

The Macrophage Mannose Receptor Regulate Mannan-Induced Psoriasis, Psoriatic Arthritis, and Rheumatoid Arthritis-Like Disease Models

PubMed Central

Hagert, Cecilia; Sareila, Outi; Kelkka, Tiina; Jalkanen, Sirpa; Holmdahl, Rikard

2018-01-01

The injection of mannan into mice can result in the development of psoriasis (Ps) and psoriatic arthritis (PsA), whereas co-injection with antibodies toward collagen type II leads to a chronic rheumatoid-like arthritis. The critical event in all these diseases is mannan-mediated activation of macrophages, causing more severe disease if the macrophages are deficient in neutrophil cytosolic factor 1 (Ncf1), i.e., lack the capacity to make a reactive oxygen species (ROS) burst. In this study, we investigated the role of one of the receptors binding mannan; the macrophage mannose receptor (MR, CD206). MR is a C-type lectin present on myeloid cells and lymphatics. We found that mice deficient in MR expression had more severe mannan-induced Ps, PsA as well as rheumatoid-like arthritis. Interestingly, the MR-mediated protection was partly lost in Ncf1 mutated mice and was associated with an type 2 macrophage expansion. In conclusion, these results show that MR protects against a pathogenic inflammatory macrophage response induced by mannan and is associated with induction of ROS. PMID:29467756

Non-cholesterol sterols and cholesterol metabolism in sitosterolemia.

PubMed

Othman, Rgia A; Myrie, Semone B; Jones, Peter J H

2013-12-01

Sitosterolemia (STSL) is a rare autosomal recessive disease, manifested by extremely elevated plant sterols (PS) in plasma and tissue, leading to xanthoma and premature atherosclerotic disease. Therapeutic approaches include limiting PS intake, interrupting enterohepatic circulation of bile acid using bile acid binding resins such as cholestyramine, and/or ileal bypass, and inhibiting intestinal sterol absorption by ezetimibe (EZE). The objective of this review is to evaluate sterol metabolism in STSL and the impact of the currently available treatments on sterol trafficking in this disease. The role of PS in initiation of xanthomas and premature atherosclerosis is also discussed. Blocking sterols absorption with EZE has revolutionized STSL patient treatment as it reduces circulating levels of non-cholesterol sterols in STSL. However, none of the available treatments including EZE have normalized plasma PS concentrations. Future studies are needed to: (i) explore where cholesterol and non-cholesterol sterols accumulate, (ii) assess to what extent these sterols in tissues can be mobilized after blocking their absorption, and (iii) define the factors governing sterol flux. Copyright © 2013. Published by Elsevier Ireland Ltd.

Increased chymase-like activity in a dog with congenital pulmonic stenosis.

PubMed

Fujii, Yoko; Yamane, Tsuyoshi; Orito, Kensuke; Osamura, Kaori; Wakao, Yoshito

2007-05-01

This study was intended to compare the tissue chymase-like activity and angiotensin converting enzyme (ACE) activity in the right and left ventricles of a dog with congenital pulmonic stenosis (PS), with normal dogs, and to discuss the potential clinical implications of these findings. Study subjects included a one-year-old Beagle dog with spontaneous PS and six clinically normal Beagles. Chymase-like and ACE activities were determined in all hearts by high pressure liquid chromatography. In the PS dog right ventricular (RV) chymase-like activity (49.79 nmol/min/g tissue) and left ventricular (LV) chymase-like activity (36.85 nmol/min/g tissue) were elevated vs normal Beagle dogs (mean+/-standard deviation, RV: 20.17+/-5.24 nmol/min/g, LV: 19.03+/-3.27 nmol/min/g). Activation of the tissue RAA system was detected in a dog with congenital PS. This interesting finding should be pursued with further studies to validate this result, and to explore whether pharmacological blockade of chymase, or the angiotensin II receptor, represents a useful strategy to prevent myocardial remodeling in this condition.

A Hidden Pitfall in the Preparation of Agar Media Undermines Microorganism Cultivability

PubMed Central

Tanaka, Tomohiro; Kawasaki, Kosei; Daimon, Serina; Kitagawa, Wataru; Yamamoto, Kyosuke; Tamaki, Hideyuki; Tanaka, Michiko; Nakatsu, Cindy H.

2014-01-01

Microbiologists have been using agar growth medium for over 120 years. It revolutionized microbiology in the 1890s when microbiologists were seeking effective methods to isolate microorganisms, which led to the successful cultivation of microorganisms as single clones. But there has been a disparity between total cell counts and cultivable cell counts on plates, often referred to as the “great plate count anomaly,” that has long been a phenomenon that still remains unsolved. Here, we report that a common practice microbiologists have employed to prepare agar medium has a hidden pitfall: when phosphate was autoclaved together with agar to prepare solid growth media (PT medium), total colony counts were remarkably lower than those grown on agar plates in which phosphate and agar were separately autoclaved and mixed right before solidification (PS medium). We used a pure culture of Gemmatimonas aurantiaca T-27T and three representative sources of environmental samples, soil, sediment, and water, as inocula and compared colony counts between PT and PS agar plates. There were higher numbers of CFU on PS medium than on PT medium using G. aurantiaca or any of the environmental samples. Chemical analysis of PT agar plates suggested that hydrogen peroxide was contributing to growth inhibition. Comparison of 454 pyrosequences of the environmental samples to the isolates revealed that taxa grown on PS medium were more reflective of the original community structure than those grown on PT medium. Moreover, more hitherto-uncultivated microbes grew on PS than on PT medium. PMID:25281372

Monitoring Photosynthesis in Individual Cells of Synechocystis sp. PCC 6803 on a Picosecond Timescale

PubMed Central

Krumova, S.B.; Laptenok, S.P.; Borst, J.W.; Ughy, B.; Gombos, Z.; Ajlani, G.; van Amerongen, H.

2010-01-01

Picosecond fluorescence kinetics of wild-type (WT) and mutant cells of Synechocystis sp. PCC 6803, were studied at the ensemble level with a streak-camera and at the cell level using fluorescence-lifetime-imaging microscopy (FLIM). The FLIM measurements are in good agreement with the ensemble measurements, but they (can) unveil variations between and within cells. The BE mutant cells, devoid of photosystem II (PSII) and of the light-harvesting phycobilisomes, allowed the study of photosystem I (PSI) in vivo for the first time, and the observed 6-ps equilibration process and 25-ps trapping process are the same as found previously for isolated PSI. No major differences are detected between different cells. The PAL mutant cells, devoid of phycobilisomes, show four lifetimes: ∼20 ps (PSI and PSII), ∼80 ps, ∼440 ps, and 2.8 ns (all due to PSII), but not all cells are identical and variations in the kinetics are traced back to differences in the PSI/PSII ratio. Finally, FLIM measurements on WT cells reveal that in some cells or parts of cells, phycobilisomes are disconnected from PSI/PSII. It is argued that the FLIM setup used can become instrumental in unraveling photosynthetic regulation mechanisms in the future. PMID:20858447

Annihilation of positronium atoms confined in mesoporous and macroporous SiO2 films

NASA Astrophysics Data System (ADS)

Cooper, B. S.; Boilot, J.-P.; Corbel, C.; Guillemot, F.; Gurung, L.; Liszkay, L.; Cassidy, D. B.

2018-05-01

We report experiments in which positronium (Ps) atoms were created in thin, porous silica films containing isolated voids with diameters ranging from 5 to 75 nm. Ps lifetimes in the pore structures were measured directly via time-delayed laser excitation of 13S1→23PJ transitions. In a film containing 5-nm pores Ps was predominantly emitted into vacuum, with a small component of confined Ps with a lifetime of 75 ns also observed. In films with larger pores Ps atoms were not emitted into vacuum except from the film surface, and confined Ps lifetimes of ≈90 ns were measured with no dependence on the pore size. However, for such large pores, extended Tao-Eldrup (ETE)-type models predict Ps lifetimes close to the 142-ns vacuum value. Moreover, 13S1→23PJ excitation of Ps atoms inside the pores was found to result in annihilation and exhibited an extremely broad (≈10 THz) linewidth. We attribute these observations to a process in which nonthermal Ps atoms in the isolated voids become temporarily trapped in a series of surface states that dissociate following excitation. The occurrence of this mechanism is not necessarily apparent from ground-state Ps decay rates without some prior knowledge of the sample structure, and it precludes the application of ETE-type models as they do not take into account surface interactions other than pickoff annihilation.

Improved optical axis determination accuracy for fiber-based polarization-sensitive optical coherence tomography

NASA Astrophysics Data System (ADS)

Lu, Zenghai; Matcher, Stephen J.

2013-03-01

We report on a new calibration technique that permits the accurate extraction of sample Jones matrix and hence fast-axis orientation by using fiber-based polarization-sensitive optical coherence tomography (PS-OCT) that is completely based on non polarization maintaining fiber such as SMF-28. In this technique, two quarter waveplates are used to completely specify the parameters of the system fibers in the sample arm so that the Jones matrix of the sample can be determined directly. The device was validated on measurements of a quarter waveplate and an equine tendon sample by a single-mode fiber-based swept-source PS-OCT system.

FIRE_CI2_ETL_RADAR

Atmospheric Science Data Center

2015-11-25

FIRE_CI2_ETL_RADAR Project Title:  FIRE II CIRRUS Discipline:  ... Platform:  Ground Station Instrument:  Radar Spatial Coverage:  (37.06, -95.34) Spatial ... Order Data Guide Documents:  ETL_RADAR Guide Readme Files:  Readme ETL_RADAR (PS) ...

Which Propensity Score Method Best Reduces Confounder Imbalance? An Example From a Retrospective Evaluation of a Childhood Obesity Intervention.

PubMed

Schroeder, Krista; Jia, Haomiao; Smaldone, Arlene

Propensity score (PS) methods are increasingly being employed by researchers to reduce bias arising from confounder imbalance when using observational data to examine intervention effects. The purpose of this study was to examine PS theory and methodology and compare application of three PS methods (matching, stratification, weighting) to determine which best improves confounder balance. Baseline characteristics of a sample of 20,518 school-aged children with severe obesity (of whom 1,054 received an obesity intervention) were assessed prior to PS application. Three PS methods were then applied to the data to determine which showed the greatest improvement in confounder balance between the intervention and control group. The effect of each PS method on the outcome variable-body mass index percentile change at one year-was also examined. SAS 9.4 and Comprehensive Meta-analysis statistical software were used for analyses. Prior to PS adjustment, the intervention and control groups differed significantly on seven of 11 potential confounders. PS matching removed all differences. PS stratification and weighting both removed one difference but created two new differences. Sensitivity analyses did not change these results. Body mass index percentile at 1 year decreased in both groups. The size of the decrease was smaller in the intervention group, and the estimate of the decrease varied by PS method. Selection of a PS method should be guided by insight from statistical theory and simulation experiments, in addition to observed improvement in confounder balance. For this data set, PS matching worked best to correct confounder imbalance. Because each method varied in correcting confounder imbalance, we recommend that multiple PS methods be compared for ability to improve confounder balance before implementation in evaluating treatment effects in observational data.

Anti-fibrotic effect of Cordyceps sinensis polysaccharide: Inhibiting HSC activation, TGF-β1/Smad signalling, MMPs and TIMPs.

PubMed

Peng, Jinghua; Li, Xuemei; Feng, Qin; Chen, Liang; Xu, Lili; Hu, Yiyang

2013-06-01

Cordyceps sinensis has been used to treat liver disease in traditional Chinese medicine for thousands of years. Polysaccharide extracted from cultured Cordyceps sinensis mycelia (CS-PS) is the major active components of cordyceps sinensis with anti-liver injury effects. In the present study, the effects of CS-PS on hepatic stellate cell (HSC) activation, transforming growth factor-β1 (TGF-β1)/Smad pathway, as well as matrix metalloproteinase (MMP) 2, MMP9 and tissue inhibitor of metalloproteinase (TIMP) 1, TIMP2, were investigated in liver fibrosis in rats induced by carbon tetrachloride (CCl4). Colchicine was used as a positive control. The effect of CS-PS inhibition liver injury and fibrosis was confirmed by decreasing serum alanine aminotransferase, aspartate aminotransferase, total bilirubin, hepatic hydroxyproline and increasing serum albumin, as well as alleviation of histological changes, which was comparable to that of colchicine. With CS-PS treatment, hepatic α-smooth muscle actin, TGF-β1, TGF-β1 receptor (TβR)-I, TβR-II, p-Smad2, p-Smad3 and TIMP2 proteins expression were down-regulated comparing to that in CCl4 group. The activities of MMP2 and MMP9 in liver tissue were also inhibited in CS-PS-treated group. It is indicated that the effects of CS-PS anti-liver fibrosis are probably associated with the inhibition on HSC activation, TGF-β1/Smads signalling pathway, as well as MMP2, MMP9 activity and TIMP2 expression.

Redox potentials of primary electron acceptor quinone molecule (QA)- and conserved energetics of photosystem II in cyanobacteria with chlorophyll a and chlorophyll d.

PubMed

Allakhverdiev, Suleyman I; Tsuchiya, Tohru; Watabe, Kazuyuki; Kojima, Akane; Los, Dmitry A; Tomo, Tatsuya; Klimov, Vyacheslav V; Mimuro, Mamoru

2011-05-10

In a previous study, we measured the redox potential of the primary electron acceptor pheophytin (Phe) a of photosystem (PS) II in the chlorophyll d-dominated cyanobacterium Acaryochloris marina and a chlorophyll a-containing cyanobacterium, Synechocystis. We obtained the midpoint redox potential (E(m)) values of -478 mV for A. marina and -536 mV for Synechocystis. In this study, we measured the redox potentials of the primary electron acceptor quinone molecule (Q(A)), i.e., E(m)(Q(A)/Q(A)(-)), of PS II and the energy difference between [P680·Phe a(-)·Q(A)] and [P680·Phe a·Q(A)(-)], i.e., ΔG(PhQ). The E(m)(Q(A)/Q(A)(-)) of A. marina was determined to be +64 mV without the Mn cluster and was estimated to be -66 to -86 mV with a Mn-depletion shift (130-150 mV), as observed with other organisms. The E(m)(Phe a/Phe a(-)) in Synechocystis was measured to be -525 mV with the Mn cluster, which is consistent with our previous report. The Mn-depleted downshift of the potential was measured to be approximately -77 mV in Synechocystis, and this value was applied to A. marina (-478 mV); the E(m)(Phe a/Phe a(-)) was estimated to be approximately -401 mV. These values gave rise to a ΔG(PhQ) of -325 mV for A. marina and -383 mV for Synechocystis. In the two cyanobacteria, the energetics in PS II were conserved, even though the potentials of Q(A)(-) and Phe a(-) were relatively shifted depending on the special pair, indicating a common strategy for electron transfer in oxygenic photosynthetic organisms.

Glufosinate ammonium clean-up procedure from water samples using SPE

NASA Astrophysics Data System (ADS)

Tayeb M., A.; Ismail B., S.; Mardiana-Jansar, K.; Ta, Goh Choo; Agustar, Hani Kartini

2015-09-01

For the determination of glufosinate ammonium residue in soil and water samples, different solid phase extraction (SPE) sorbent efficiency was studied. Four different SPE sorbents i.e.: CROMABOND PS-H+, CROMABOND PS-OH-, ISOLUTE ENV+, Water Sep-Pak and OASIS HLB were used. Sample clean-up performance was evaluated using high performance liquid chromatography (Agilent 1220 infinity LC) with fluorescence detector. Detection of FMO-derivatives was done at λ ex = 260 nm and λ em= 310 nm. OASIS HLB column was the most suitable for the clean-up in view of the overall feasibility of the analysis.

Impact of use of angiotensin II receptor blocker on all-cause mortality in hemodialysis patients: prospective cohort study using a propensity-score analysis.

PubMed

Tanaka, Marenao; Yamashita, Tomohisa; Koyama, Masayuki; Moniwa, Norihito; Ohno, Kohei; Mitsumata, Kaneto; Itoh, Takahito; Furuhashi, Masato; Ohnishi, Hirofumi; Yoshida, Hideaki; Tsuchihashi, Kazufumi; Miura, Tetsuji

2016-06-01

It is controversial whether treatment with an angiotensin II receptor blocker (ARB) or a calcium channel blocker (CCB) improves prognosis of hemodialysis (HD) patients. This study was designed as a multicenter prospective cohort study. HD patients (n = 1071) were enrolled from 22 institutes in January 2009 and followed up for 3 years. Patients with missing data, kidney transplantation or retraction of consent during the follow-up period (n = 204) were excluded, and 867 patients contributed to analysis of mortality. Propensity score (PS) for use of ARB and that for CCB was calculated using a multiple logistic regression model. ARB and CCB were prescribed in 45.6 and 54.7 % of patients at enrollment. During the 3-year follow-up period, all-cause mortality and cardiovascular mortality rates were 18.8 and 5.1 %, respectively. Kaplan-Meier curves showed that all-cause and cardiovascular mortality rates were lower in the ARB group than in the non-ARB group, though the mortality rates were similar in the CCB group and non-CCB group. In PS-stratified Cox regression analysis, ARB treatment was associated with 34 and 45 % reduction of all-cause death and cardiovascular death, respectively. In PS matching analysis, ARB treatment was associated with a significant reduction (46 % reduction) in the risk of all-cause death. A significant impact of CCB treatment on all-cause or cardiovascular mortality was not detected in PS analysis. The use of an ARB, but not a CCB, is associated with reduced all-cause and cardiovascular mortalities in patients on HD.

Excess copper induces anoxygenic photosynthesis in Anabaena doliolum: a homology based proteomic assessment of its survival strategy.

PubMed

Bhargava, Poonam; Mishra, Yogesh; Srivastava, Ashish Kumar; Narayan, Om Prakash; Rai, Lal Chand

2008-04-01

This study is the first to demonstrate operation of anoxygenic photosynthesis in copper acclimated Anabaena doliolum and to offer proteomic comparison with the control cells. The Cu-treated control strain showed a negative correlation in growth and intracellular Cu, partial inhibition of O(2)-evolution, PS II, PS I, whole chain, chlorophyll absorption, and nitrogenase activity. However, the acclimated strain growing in 250-fold excess Cu exhibited near normal growth, ATP content, PS I activity, carbon fixation, and almost complete inhibition of O(2)-evolution, PS II and chlorophyll absorption, but increased nitrogenase activity as compared to control. Proteomic decoding of the survival strategy of Cu-treated control and the acclimated strain using two-dimensional gel electrophoresis and MALDI-TOF MS analysis of proteins displaying significant and reproducible changes demonstrated involvement of transketolase, phycoerythrocyanin alpha-chain, iron superoxide dismutase (Fe-SOD), hypothetical protein alr 0803, manganese superoxide dismutase (Mn-SOD), phosphoribulokinase, and plastocyanin (PLC). Expression pattern of these proteins was attested at the transcriptional level using RT-PCR. Time course analysis of proteins of Cu-treated control strain revealed almost no change in PLC level, and a minor accumulation of transketolase, phycoerythrocyanin alpha-chain and both isoforms of SOD after 7 and recovery after 10 days. Acclimated strain under excess Cu, however, exhibited significant accumulation of both isoforms of SOD, plastocyanin, phosphoribulokinase and transketolase, which seem to counteract oxidative damage, serve as an alternate electron carrier from cytochrome b6/f complex to photosystem I and meet the NADPH and ATP requirements, respectively, under anoxygenic photosynthesis. In view of the kinetics of the hypothetical protein alr0803 (no change in expression level for 7, maximum after 10 and decline after 15 days) its involvement in metal homeostasis is suggested.

Which neuropsychological functions predict various processing speed components in children with and without attention-deficit/hyperactivity disorder?

PubMed

Vadnais, Sarah A; Kibby, Michelle Y; Jagger-Rickels, Audreyana C

2018-01-01

We identified statistical predictors of four processing speed (PS) components in a sample of 151 children with and without attention-deficit/hyperactivity disorder (ADHD). Performance on perceptual speed was predicted by visual attention/short-term memory, whereas incidental learning/psychomotor speed was predicted by verbal working memory. Rapid naming was predictive of each PS component assessed, and inhibition predicted all but one task, suggesting a shared need to identify/retrieve stimuli rapidly and inhibit incorrect responding across PS components. Hence, we found both shared and unique predictors of perceptual, cognitive, and output speed, suggesting more specific terminology should be used in future research on PS in ADHD.

Chemical characteristics of saponins from Paris fargesii var. brevipetala and cytotoxic activity of its main ingredient, paris saponin H.

PubMed

Wen, Feiyan; Yin, Hongxiang; Chen, Chu; Liu, Xianbo; Xue, Dan; Chen, Tiezhu; He, Jun; Zhang, Hao

2012-06-01

More attention was paid to the anti-tumor activity of Rhizoma Paridis (RP) recently, of which the wild resource was decreased significantly. This study was aimed to elucidate the chemical characteristics of Paris fargesii var. brevipetala (PFB) that may be administrated as alternate resource of legal RP. A HPLC-ELSD method was established to characterize the steroid saponins in rhizomes of PFB and two legal Paris species [Paris polyphylla var. chinensis (PPC) and P. polyphylla var. yunnanensis (PPY)] in Chinese Pharmacopoeia (CP). Ten saponins (paris saponins I, II, V, VI, VII, H, gracillin and other three paris saponins) were involved as standards. The results indicated that PFB contained pennogenyl saponins as the main components with small amounts of diosgenin saponins. The total contents of the detected saponins in PFB ranged from 9.12mg/g to 85.33mg/g. Nine of the twelve PFB samples own a total content of paris saponins I, II, VI, and VII more than 6.0mg/g (meeting the standard of CP 2010 edition). Principal Component Analysis (PCA) and Partial Least Squares-Discriminate Analysis (PLS-DA) both confirmed the fact that saponin profiles of PFB, PPC and PPY were different from each other. In addition, paris saponin H (Ps H), the predominant saponin of PFB (>50%), was tested in vitro to evaluate its cytotoxic activities on HepG2, A549, RPE and L929 cells with a positive control of Cisplatin. Ps H showed a remarkable cytotoxic activity on A549 cells with an IC(50) value of 1.53±0.08μg/mL. Copyright © 2012 Elsevier B.V. All rights reserved.

Decoherence mechanisms of Landau level THz excitations in two dimensional electron gases

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

Maissen, Curdin; Scalari, Giacomo; Faist, Jérôme

2013-12-04

We report coherent THz transmission measurements on different two dimensional electron gases (2DEGs) in magnetic field. The investigated 2DEGs form in GaAs/AlGaAs heterostructures. A short (1 ps) linearly polarized THz pulse is used to excite inter Landau level transitions. The circular polarized radiation emitted by the 2DEG is then measured by electro optic sampling of the linear component orthogonal to the pump pulse polarization. Here we present measurements on two high mobility samples with μ = 5×10{sup 6}cm{sup 2}/Vs and μ = 16×10{sup 6}cm{sup 2}/Vs respectively. The decay times of the emitted radiation are 5.5 ps and 9 ps respectivelymore » at 2 K.« less

Early Identification of Herbicide Stress in Soybean (Glycine max (L.) Merr.) Using Chlorophyll Fluorescence Imaging Technology

PubMed Central

Li, Hui; Wang, Pei; Weber, Jonas Felix; Gerhards, Roland

2017-01-01

Herbicides may damage soybean in conventional production systems. Chlorophyll fluorescence imaging technology has been applied to identify herbicide stress in weed species a few days after application. In this study, greenhouse experiments followed by field experiments at five sites were conducted to investigate if the chlorophyll fluorescence imaging is capable of identifying herbicide stress in soybean shortly after application. Measurements were carried out from emergence until the three-to-four-leaf stage of the soybean plants. Results showed that maximal photosystem II (PS II) quantum yield and shoot dry biomass was significantly reduced in soybean by herbicides compared to the untreated control plants. The stress of PS II inhibiting herbicides occurred on the cotyledons of soybean and plants recovered after one week. The stress induced by DOXP synthase-, microtubule assembly-, or cell division-inhibitors was measured from the two-leaf stage until four-leaf stage of soybean. We could demonstrate that the chlorophyll fluorescence imaging technology is capable for detecting herbicide stress in soybean. The system can be applied under both greenhouse and field conditions. This helps farmers to select weed control strategies with less phytotoxicity in soybean and avoid yield losses due to herbicide stress. PMID:29271905

Early Identification of Herbicide Stress in Soybean (Glycine max (L.) Merr.) Using Chlorophyll Fluorescence Imaging Technology.

PubMed

Li, Hui; Wang, Pei; Weber, Jonas Felix; Gerhards, Roland

2017-12-22

Herbicides may damage soybean in conventional production systems. Chlorophyll fluorescence imaging technology has been applied to identify herbicide stress in weed species a few days after application. In this study, greenhouse experiments followed by field experiments at five sites were conducted to investigate if the chlorophyll fluorescence imaging is capable of identifying herbicide stress in soybean shortly after application. Measurements were carried out from emergence until the three-to-four-leaf stage of the soybean plants. Results showed that maximal photosystem II (PS II) quantum yield and shoot dry biomass was significantly reduced in soybean by herbicides compared to the untreated control plants. The stress of PS II inhibiting herbicides occurred on the cotyledons of soybean and plants recovered after one week. The stress induced by DOXP synthase-, microtubule assembly-, or cell division-inhibitors was measured from the two-leaf stage until four-leaf stage of soybean. We could demonstrate that the chlorophyll fluorescence imaging technology is capable for detecting herbicide stress in soybean. The system can be applied under both greenhouse and field conditions. This helps farmers to select weed control strategies with less phytotoxicity in soybean and avoid yield losses due to herbicide stress.

Impact of Blood Flow Restriction Exercise on Muscle Fatigue Development and Recovery.

PubMed

Husmann, Florian; Mittlmeier, Thomas; Bruhn, Sven; Zschorlich, Volker; Behrens, Martin

2018-03-01

The present study was designed to provide mechanistic insight into the time course and etiology of muscle fatigue development and recovery during and after low-intensity exercise when it is combined with blood flow restriction (BFR). Seventeen resistance-trained males completed four sets of low-intensity isotonic resistance exercise under two experimental conditions: knee extension exercise (i) with BFR and (ii) without BFR (CON). Neuromuscular tests were performed before, during (immediately after each set of knee extension exercise), and 1, 2, 4, and 8 min after each experimental condition. Maximal voluntary torque, quadriceps twitch torque in response to paired electrical stimuli at 10 Hz (PS10) and 100 Hz (PS100), PS10·PS100 ratio as an index of low-frequency fatigue, and voluntary activation were measured under isometric conditions. Perceptual and EMG data were recorded during each exercise condition. After the first set of exercise, BFR induced significantly greater reductions in maximal voluntary torque, PS100, and PS10·PS100 ratio compared with CON. These parameters progressively declined throughout the BFR protocol but recovered substantially within 2 min postexercise when blood flow was restored. Neither a progressive decline in the course of the exercise protocol nor a substantial recovery of these parameters occurred during and after CON. Only at exercise termination, voluntary activation differed significantly between BFR and CON with greater reductions during BFR. At the early stage of exercise, BFR exacerbated the development of muscle fatigue mainly due to a pronounced impairment in contractile function. Despite the high level of muscle fatigue during BFR exercise, the effect of BFR on muscle fatigue was diminished after 2 min of reperfusion, suggesting that BFR has a strong but short-lasting effect on neuromuscular function.

Acne vulgaris in early adolescent boys. Correlations with pubertal maturation and age.

PubMed

Lucky, A W; Biro, F M; Huster, G A; Morrison, J A; Elder, N

1991-02-01

To assess the prevalence and severity of acne vulgaris in young adolescent boys, we studied 219 black and 249 white boys in fifth through ninth grades in Cincinnati, Ohio. The mean age was 12.2 +/- 1.4 years, with a range of 9 to 15 years. Pubertal maturation was scored as Tanner pubic hair stages (PH I to V) and pubertal stages (PS I to IV) that included testicular volume assessment. Acne was scored by number of comedonal (open plus closed comedones) and inflammatory (papules plus pustules) lesions. Comedonal and inflammatory lesions were analyzed separately and evaluated both as numerical scores and as grades (1, less than or equal to 10 lesions; 2, 11 to 25 lesions; and 3, greater than or equal to 26 lesions). Grades 2 and 3 were considered clinically significant acne. Acne became progressively more severe with advancing maturity. Mean acne scores correlated better with PS and pubic hair than with age. Black subjects were more mature than white subjects. Black boys in PSI and II had significantly more comedones than white boys; white boys had significantly more inflammatory lesions at PS I and III. Clinically significant comedonal acne was already present in PS I and occurred in 100% of boys in PS IV. In contrast, no boys at PS I and only 50% at PS IV had significant inflammatory acne. Midfacial acne dominated. We concluded that acne prevalence and severity correlate well with advancing pubertal maturation in young adolescent boys. Comedonal acne was more frequent and severe than inflammatory disease. Awareness of the extent and severity of acne in preadolescents and young adolescents may ultimately provide rationale for early intervention and thus prevention of severe acne vulgaris.

Characterizing of tissue microstructure with single-detector polarization-sensitive optical coherence tomography

NASA Astrophysics Data System (ADS)

Liu, Bin; Harman, Michelle; Giattina, Susanne; Stamper, Debra L.; Demakis, Charles; Chilek, Mark; Raby, Stephanie; Brezinski, Mark E.

2006-06-01

Assessing tissue birefringence with imaging modality polarization-sensitive optical coherence tomography (PS-OCT) could improve the characterization of in vivo tissue pathology. Among the birefringent components, collagen may provide invaluable clinical information because of its alteration in disorders ranging from myocardial infarction to arthritis. But the features required of clinical imaging modality in these areas usually include the ability to assess the parameter of interest rapidly and without extensive data analysis, the characteristics that single-detector PS-OCT demonstrates. But beyond detecting organized collagen, which has been previously demonstrated and confirmed with the appropriate histological techniques, additional information can potentially be gained with PS-OCT, including collagen type, form versus intrinsic birefringence, the collagen angle, and the presence of multiple birefringence materials. In part I, we apply the simple but powerful fast-Fourier transform (FFT) to both PS-OCT mathematical modeling and in vitro bovine meniscus for improved PS-OCT data analysis. The FFT analysis yields, in a rapid, straightforward, and easily interpreted manner, information on the presence of multiple birefringent materials, distinguishing the true anatomical structure from patterns in image resulting from alterations in the polarization state and identifying the tissue/phantom optical axes. Therefore the use of the FFT analysis of PS-OCT data provides information on tissue composition beyond identifying the presence of organized collagen in real time and directly from the image without extensive mathematical manipulation or data analysis. In part II, Helistat phantoms (collagen type I) are analyzed with the ultimate goal of improved tissue characterization. This study, along with the data in part I, advance the insights gained from PS-OCT images beyond simply determining the presence or absence of birefringence.

Longitudinal DSC-MRI for Distinguishing Tumor Recurrence From Pseudoprogression in Patients With a High-grade Glioma.

PubMed

Boxerman, Jerrold L; Ellingson, Benjamin M; Jeyapalan, Suriya; Elinzano, Heinrich; Harris, Robert J; Rogg, Jeffrey M; Pope, Whitney B; Safran, Howard

2017-06-01

For patients with high-grade glioma on clinical trials it is important to accurately assess time of disease progression. However, differentiation between pseudoprogression (PsP) and progressive disease (PD) is unreliable with standard magnetic resonance imaging (MRI) techniques. Dynamic susceptibility contrast perfusion MRI (DSC-MRI) can measure relative cerebral blood volume (rCBV) and may help distinguish PsP from PD. A subset of patients with high-grade glioma on a phase II clinical trial with temozolomide, paclitaxel poliglumex, and concurrent radiation were assessed. Nine patients (3 grade III, 6 grade IV), with a total of 19 enhancing lesions demonstrating progressive enhancement (≥25% increase from nadir) on postchemoradiation conventional contrast-enhanced MRI, had serial DSC-MRI. Mean leakage-corrected rCBV within enhancing lesions was computed for all postchemoradiation time points. Of the 19 progressively enhancing lesions, 10 were classified as PsP and 9 as PD by biopsy/surgery or serial enhancement patterns during interval follow-up MRI. Mean rCBV at initial progressive enhancement did not differ significantly between PsP and PD (2.35 vs. 2.17; P=0.67). However, change in rCBV at first subsequent follow-up (-0.84 vs. 0.84; P=0.001) and the overall linear trend in rCBV after initial progressive enhancement (negative vs. positive slope; P=0.04) differed significantly between PsP and PD. Longitudinal trends in rCBV may be more useful than absolute rCBV in distinguishing PsP from PD in chemoradiation-treated high-grade gliomas with DSC-MRI. Further studies of DSC-MRI in high-grade glioma as a potential technique for distinguishing PsP from PD are indicated.

Measurement of the B 0 s lifetime in the flavor-specific decay channel B 0 s → D - sμ +νX

DOE PAGES

Abazov, Victor Mukhamedovich

2015-02-09

We present an updated measurement of the B 0 s lifetime using the semileptonic decays B 0 s → D - sμ +νX, with D – s → π – and Φ → K +K – (and the charge conjugate process). This measurement uses the full Tevatron Run II sample of proton-antiproton collisions at √s = 1.96 TeV, comprising an integrated luminosity of 10.4 fb –1. We find a flavor-specific lifetime τ fs(B 0 s) = 1.479 ± 0.010(stat) ± 0.021(syst) ps. This technique is also used to determine the B 0 lifetime using the analogous B 0 → Dmore » –μ +νX decay with D – → Φπ – and Φ → K +K –, yielding τ(B 0) = 1.534 ± 0.019(stat) ± 0.021(syst) ps. Both measurements are consistent with the current world averages, and the B 0 s lifetime measurement is one of the most precise to date. As a result, taking advantage of the cancellation of systematic uncertainties, we determine the lifetime ratio τ fs(B 0 s)/τ(B 0) = 0.964 ± 0.013(stat) ± 0.007(syst).« less

Application of scanning angle Raman spectroscopy for determining the location of buried polymer interfaces with tens of nanometer precision

DOE PAGES

Damin, Craig A.; Nguyen, Vy H. T.; Niyibizi, Auguste S.; ...

2015-02-11

In this study, near-infrared scanning angle (SA) Raman spectroscopy was utilized to determine the interface location in bilayer films (a stack of two polymer layers) of polystyrene (PS) and polycarbonate (PC). Finite-difference-time-domain (FDTD) calculations of the sum square electric field (SSEF) for films with total bilayer thicknesses of 1200–3600 nm were used to construct models for simultaneously measuring the film thickness and the location of the buried interface between the PS and PC layers. Samples with total thicknesses of 1320, 1890, 2300, and 2750 nm and varying PS/PC interface locations were analyzed using SA Raman spectroscopy. Comparing SA Raman spectroscopymore » and optical profilometry measurements, the average percent difference in the total bilayer thickness was 2.0% for films less than ~2300 nm thick. The average percent difference in the thickness of the PS layer, which reflects the interface location, was 2.5% when the PS layer was less than ~1800 nm. SA Raman spectroscopy has been shown to be a viable, non-destructive method capable of determining the total bilayer thickness and buried interface location for bilayer samples consisting of thin polymer films with comparable indices of refraction.« less

Polarization properties of amyloid-beta plaques in Alzheimer's disease (Conference Presentation)

NASA Astrophysics Data System (ADS)

Baumann, Bernhard; Wöhrer, Adelheid; Ricken, Gerda; Pircher, Michael; Kovacs, Gabor G.; Hitzenberger, Christoph K.

2016-03-01

In histopathological practice, birefringence is used for the identification of amyloidosis in numerous tissues. Amyloid birefringence is caused by the parallel arrangement of fibrous protein aggregates. Since neurodegenerative processes in Alzheimer's disease (AD) are also linked to the formation of amyloid-beta (Aβ) plaques, optical methods sensitive to birefringence may act as non-invasive tools for Aβ identification. At last year's Photonics West, we demonstrated polarization-sensitive optical coherence tomography (PS-OCT) imaging of ex vivo cerebral tissue of advanced stage AD patients. PS-OCT provides volumetric, structural imaging based on both backscatter contrast and tissue polarization properties. In this presentation, we report on polarization-sensitive neuroimaging along with numerical simulations of three-dimensional Aβ plaques. High speed PS-OCT imaging was performed using a spectral domain approach based on polarization maintaining fiber optics. The sample beam was interfaced to a confocal scanning microscope arrangement. Formalin-fixed tissue samples as well as thin histological sections were imaged. For comparison to the PS-OCT results, ray propagation through plaques was modeled using Jones analysis and various illumination geometries and plaque sizes. Characteristic polarization patterns were found. The results of this study may not only help to understand PS-OCT imaging of neuritic Aβ plaques but may also have implications for polarization-sensitive imaging of other fibrillary structures.

Comparison of Adsorption/Desorption of Volatile Organic Compounds (VOCs) on Electrospun Nanofibers with Tenax TA for Potential Application in Sampling

PubMed Central

Chu, Lanling; Deng, Siwei; Zhao, Renshan; Deng, Jianjun; Kang, Xuejun

2016-01-01

The objective of this study was to compare the adsorption/desorption of target compounds on homemade electrospun nanofibers, polystyrene (PS) nanofibers, acrylic resin (AR) nanofibers and PS-AR composite nanofibers with Tenax TA. Ten volatile organic compounds (VOCs) were analyzed by preconcentration onto different sorbents followed by desorption (thermal and solvent orderly) and analysis by capillary gas chromatography. In comparison to Tenax TA, the electrospun nanofibers displayed a significant advantage in desorption efficiency and adsorption selectivity. Stability studies were conducted as a comparative experiment between PS-AR nanofibers and Tenax TA using toluene as the model compound. No stability problems were observed upon storage of toluene on both PS-AR nanofibers and Tenax TA over 60 hours period when maintained in an ultra-freezer (−80°C). The nanofibers provided slightly better stability for the adsorbed analytes than Tenax TA under other storage conditions. In addition, the nanofibers also provided slightly better precision than Tenax TA. The quantitative adsorption of PS-AR nanofibers exhibited a good linearity, as evidenced by the 0.988–0.999 range of regression coefficients (R). These results suggest that for VOCs sampling the electrospun nanofibers can be a potential ideal adsorbent. PMID:27776140

Rapid analysis of Aurantii Fructus Immaturus (Zhishi) using paper spray ionization mass spectrometry.

PubMed

Liu, Xuemei; Gu, Zhixin; Guo, Yuan; Liu, Jingjing; Ma, Ming; Chen, Bo; Wang, Liping

2017-04-15

Paper spray-mass spectrometry (PS-MS) is a rapid, solvent-efficient, and high-throughput analytical method for analyzing complex samples. In this study, a PS-MS method was developed to obtain MS profiles of Aurantii Fructus Immaturus (aka Zhishi in Chinese) in positive and negative ion modes. In combination with multivariate analyses, including principal component analysis and cluster analysis, the PS-MS profiles of 25 batches of Zhishi were discriminated in 25 batches of Citri Reticulatae Pericarpium Viride (aka Qingpi in Chinese; an adulterant of Zhishi). Moreover, a rapid quantitative analysis of synephrine, a prescriptive quality control component of Zhishi listed in the Chinese Pharmacopoeia, was conducted with PS-MS using synephrine-d2 as an internal standard (IS). The linearity range was 1.68-16.8μg/mL (R 2 =0.9985), the limit of quantitation was 0.5μg/mL. Relative standard deviations in the intra- and inter-day precision of the MS were 4.87 and 4.90%, respectively. Compared with HPLC results, there was no significant difference in the quantitation of synephrine. This study demonstrated that the PS-MS method is useful for the rapid discrimination and quality control of Zhishi samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Cannabis Use, Polysubstance Use, and Psychosis Spectrum Symptoms in a Community-Based Sample of US Youth

PubMed Central

Jones, Jason D.; Calkins, Monica E.; Scott, J. Cobb; Bach, Emily C.; Gur, Raquel E.

2017-01-01

Purpose To examine how cannabis use and polysubstance use among cannabis users relate to psychosis spectrum (PS) symptoms in a large community-based sample of US youth. Methods 4,171 youth (age 14–21; mean=16.90, SD=1.85; 55% female) from the Philadelphia Neurodevelopmental Cohort (PNC) completed assessments of substance use, PS symptoms, and confounding variables (e.g., demographics, comorbid psychopathology, trauma exposure). Results After adjusting for confounds, cannabis use by itself was not associated with increased odds of being classified as “psychosis spectrum.” However, cannabis use in combination with tobacco or other substance use was associated with increased odds of PS classification (adjusted odds ratios [ORs] = 1.37 to 1.76). Follow-up symptom-level analyses revealed that cannabis use in combination with other substances was associated with subclinical positive symptoms (ORs=1.95 and 2.24) and frequent cannabis use was associated with subclinical negative/disorganized symptoms (OR=2.14). However, these symptom-level findings were reduced to trends after correction for multiple comparisons. Neither cannabis use nor polysubstance use was associated with threshold delusions or hallucinations. Conclusions After adjusting for important confounds, there was minimal evidence for associations between cannabis use by itself and PS symptoms. More compelling evidence emerged for associations between polysubstance use among cannabis users and PS symptoms. This study highlights the importance of considering polysubstance use and confounds when examining associations between cannabis use and PS symptoms. Further longitudinal research is necessary to determine whether these findings represent causal associations or shared genetic and/or environmental vulnerability for substance use and PS symptoms. PMID:28318911

In vitro inhibition of human papillomavirus following use of a carrageenan-containing vaginal gel.

PubMed

Novetsky, Akiva P; Keller, Marla J; Gradissimo, Ana; Chen, Zigui; Morgan, Stephanie L; Xue, Xiaonan; Strickler, Howard D; Fernández-Romero, José A; Burk, Robert; Einstein, Mark H

2016-11-01

To assess in vitro efficacy of Divine 9, a carrageenan-based vaginal lubricant that is being studied as a microbicide to inhibit HPV16 pseudovirus (PsV) infection. Sexually active US women between 19 and 35years without prior HPV vaccination or cervical intraepithelial neoplasia were instructed to use Divine 9 vaginally with an applicator either before sex only or before and after intercourse. Women who applied a single dose of gel returned for cervicovaginal lavage (CVL) collection 1, 4 or 8-12h after intercourse versus those who applied gel before and after intercourse returned 1, 4 or 8-12h after the second gel dose. Carrageenan concentrations were assessed using an ELISA assay and the inhibitory activity was assessed using a PsV-based neutralization assay against HPV16 infection. Carrageenan concentrations and the percentage of PsV16 inhibition were compared using the Wilcoxon rank sum test. Thirteen women were enrolled and thirty specimens from different time-points were assessed. 87% of CVL samples had detectable carrageenans with levels decreasing over time from intercourse. 93% of CVL samples had detectable PsV16 inhibition with median inhibition of 97.5%. PsV16 inhibition decreased over time, but remained high, with median inhibition of 98.1%, 97.4% and 83.4% at 1, 4 and 8-12h, respectively. Higher carrageenan concentrations were associated with higher levels of PsV16 inhibition (rho=0.69). This is the first report of a human study investigating in vitro HPV inhibition of a carrageenan-based vaginal lubricant with CVL collected after sexual intercourse. We demonstrate excellent efficacy in preventing PsV16 infection. Copyright © 2016 Elsevier Inc. All rights reserved.

In Vitro Inhibition of Human Papillomavirus Following Use of a Carrageenan-Containing Vaginal Gel

PubMed Central

Novetsky, Akiva P.; Keller, Marla J.; Gradissimo, Ana; Chen, Zigui; Morgan, Stephanie L.; Xue, Xiaonan; Strickler, Howard D.; Fernández-Romero, José A.; Burk, Robert; Einstein, Mark H.

2016-01-01

Objective To assess in vitro efficacy of Divine 9, a carrageenan-based vaginal lubricant that is being studied as a microbicide to inhibit HPV16 pseudovirus (PsV) infection. Methods Sexually active US women between 19–35 years without prior HPV vaccination or cervical intraepithelial neoplasia were instructed to use Divine 9 vaginally with an applicator either before sex only or before and after intercourse. Women who applied a single dose of gel returned for cervicovaginal lavage (CVL) collection 1, 4 or 8–12 hours after intercourse versus those who applied gel before and after intercourse returned 1, 4 or 8–12 hours after the second gel dose. Carrageenan concentrations were assessed using an ELISA assay and the inhibitory activity was assessed using a PsV-based neutralization assay against HPV16 infection. Carrageenan concentrations and the percentage of PsV16 inhibition were compared using the Wilcoxon rank sum test. Results Thirteen women were enrolled and thirty specimens from different time-points were assessed. 87% of CVL samples had detectable carrageenans with levels decreasing over time from intercourse. 93% of CVL samples had detectable PsV16 inhibition with median inhibition of 97.5%. PsV16 inhibition decreased over time, but remained high, with median inhibition of 98.1%, 97.4% and 83.4% at 1, 4 and 8–12 hours, respectively. Higher carrageenan concentrations were associated with higher levels of PsV16 inhibition (rho=0.69). Conclusions This is the first report of a human study investigating in vitro HPV inhibition of a carrageenan-based vaginal lubricant with CVL collected after sexual intercourse. We demonstrate excellent efficacy in preventing PsV16 infection. PMID:27625046

Cannabis Use, Polysubstance Use, and Psychosis Spectrum Symptoms in a Community-Based Sample of U.S. Youth.

PubMed

Jones, Jason D; Calkins, Monica E; Scott, J Cobb; Bach, Emily C; Gur, Raquel E

2017-06-01

To examine how cannabis use and polysubstance use among cannabis users relate to psychosis spectrum (PS) symptoms in a large community-based sample of U.S. youth. Four thousand one hundred seventy-one youths (aged 14-21 years; mean = 16.90 years, SD = 1.85; 55% female) from the Philadelphia Neurodevelopmental Cohort completed assessments of substance use, PS symptoms, and confounding variables (e.g., demographics, comorbid psychopathology, and trauma exposure). After adjusting for confounds, cannabis use by itself was not associated with increased odds of being classified as "psychosis spectrum." However, cannabis use in combination with tobacco or other substance use was associated with increased odds of PS classification (adjusted odds ratios [ORs] = 1.37-1.76). Follow-up symptom-level analyses revealed that cannabis use in combination with other substances was associated with subclinical positive symptoms (ORs = 1.95 and 2.24) and frequent cannabis use was associated with subclinical negative/disorganized symptoms (OR = 2.14). However, these symptom-level findings were reduced to trends after correction for multiple comparisons. Neither cannabis use nor polysubstance use was associated with threshold delusions or hallucinations. After adjusting for important confounds, there was minimal evidence for associations between cannabis use by itself and PS symptoms. More compelling evidence emerged for associations between polysubstance use among cannabis users and PS symptoms. This study highlights the importance of considering polysubstance use and confounds when examining associations between cannabis use and PS symptoms. Further longitudinal research is necessary to determine whether these findings represent causal associations or shared genetic and/or environmental vulnerability for substance use and PS symptoms. Copyright © 2017 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

NMR investigation of the isolated second voltage-sensing domain of human Nav1.4 channel.

PubMed

Paramonov, A S; Lyukmanova, E N; Myshkin, M Yu; Shulepko, M A; Kulbatskii, D S; Petrosian, N S; Chugunov, A O; Dolgikh, D A; Kirpichnikov, M P; Arseniev, A S; Shenkarev, Z O

2017-03-01

Voltage-gated Na + channels are essential for the functioning of cardiovascular, muscular, and nervous systems. The α-subunit of eukaryotic Na + channel consists of ~2000 amino acid residues and encloses 24 transmembrane (TM) helices, which form five membrane domains: four voltage-sensing (VSD) and one pore domain. The structural complexity significantly impedes recombinant production and structural studies of full-sized Na + channels. Modular organization of voltage-gated channels gives an idea for studying of the isolated second VSD of human skeletal muscle Nav1.4 channel (VSD-II). Several variants of VSD-II (~150a.a., four TM helices) with different N- and C-termini were produced by cell-free expression. Screening of membrane mimetics revealed low stability of VSD-II samples in media containing phospholipids (bicelles, nanodiscs) associated with the aggregation of electrically neutral domain molecules. The almost complete resonance assignment of 13 C, 15 N-labeled VSD-II was obtained in LPPG micelles. The secondary structure of VSD-II showed similarity with the structures of bacterial Na + channels. The fragment of S4 TM helix between the first and second conserved Arg residues probably adopts 3 10 -helical conformation. Water accessibility of S3 helix, observed by the Mn 2+ titration, pointed to the formation of water-filled crevices in the micelle embedded VSD-II. 15 N relaxation data revealed characteristic pattern of μs-ms time scale motions in the VSD-II regions sharing expected interhelical contacts. VSD-II demonstrated enhanced mobility at ps-ns time scale as compared to isolated VSDs of K + channels. These results validate structural studies of isolated VSDs of Na + channels and show possible pitfalls in application of this 'divide and conquer' approach. Copyright © 2017 Elsevier B.V. All rights reserved.

[Effects of soil acidity on Pinus resinosa seedlings photosynthesis and chlorophyll fluorescence].

PubMed

Liu, Shuang; Wang, Qing-cheng; Liu, Ya-li; Tian, Yu-ming; Sun, Jing; Xu, Jing

2009-12-01

Red pine (Pinus resinosa) is one of the most important tree species for timber plantation in North America, and preliminary success has been achieved in its introduction to the mountainous area of Northeast China since 2004. In order to expand its growth area in other parts of Northeast China, a pot experiment was conducted to study the adaptability of this tree species to varying soil acidity. P. resinosa seedlings were grown in soils with different acidity (pH = 4.5, 5.5, 6.5, 7.5, and 8.0) to test the responses of their photosynthesis and chlorophyll fluorescence parameters to soil pH levels, and the appropriate soil acidity was evaluated. Dramatic responses in chlorophyll a and b contents, Pn and chlorophyll fluorescence parameters (Fo, Fm, Fv, Fv/Fm, and phi(PS II)) were detected under different soil acidity (P < 0.05), with the highest chlorophyll content and Pn under soil pH 5.5, and significantly lower chlorophyll content and Pn under soil pH 7.5 and 8.0. The chlorophyll content and Pn were 41% and 50%, and 61% and 88% higher under soil pH 5.5 than under soil pH 7.5 and 8.0. The seedlings had a significant photosynthetic inhibition under soil pH 7.5 and 8.0, but the highest Fv/Fm and phi (PS II) under soil pH 5.5. Comparing with those under soil pH 7.5 and 8.0, the Fv/Fm and phi (PS II) under soil pH 5.5 were 8% and 12%, and 22% and 35% higher, respectively. It was suggested that soil pH 5.5 was most appropriate for P. resinosa growth.

Molecular modeling and computational simulation of the photosystem-II reaction center to address isoproturon resistance in Phalaris minor.

PubMed

Singh, Durg Vijay; Agarwal, Shikha; Kesharwani, Rajesh Kumar; Misra, Krishna

2012-08-01

Isoproturon is the only herbicide that can control Phalaris minor, a competitive weed of wheat that developed resistance in 1992. Resistance against isoproturon was reported to be due to a mutation in the psbA gene that encodes the isoproturon-binding D1 protein. Previously in our laboratory, a triazole derivative of isoproturon (TDI) was synthesized and found to be active against both susceptible and resistant biotypes at 0.5 kg/ha but has shown poor specificity. In the present study, both susceptible D1((S)), resistant D1((R)) and D2 proteins of the PS-II reaction center of P. minor have been modeled and simulated, selecting the crystal structure of PS-II from Thermosynechococcus elongatus (2AXT.pdb) as template. Loop regions were refined, and the complete reaction center D1/D2 was simulated with GROMACS in lipid (1-palmitoyl-2-oleoylglycero-3-phosphoglycerol, POPG) environment along with ligands and cofactor. Both S and R models were energy minimized using steepest decent equilibrated with isotropic pressure coupling and temperature coupling using a Berendsen protocol, and subjected to 1,000 ps of MD simulation. As a result of MD simulation, the best model obtained in lipid environment had five chlorophylls, two plastoquinones, two phenophytins and a bicarbonate ion along with cofactor Fe and oxygen evolving center (OEC). The triazole derivative of isoproturon was used as lead molecule for docking. The best worked out conformation of TDI was chosen for receptor-based de novo ligand design. In silico designed molecules were screened and, as a result, only those molecules that show higher docking and binding energies in comparison to isoproturon and its triazole derivative were proposed for synthesis in order to get more potent, non-resistant and more selective TDI analogs.

[Effects of temperature regime on low-light tolerance of Cucumis sativus seedling leaves in their photosynthesis].

PubMed

Li, Wei; Sui, Xiao-lei; Zhang, Zhen-xian

2008-12-01

In a phytotron, the effects of three temperature regimes (day/night 25 degrees C/18 degrees C, optimal temperature; 15 degrees C/9 degrees C, suboptimal temperature; and 9 degrees C/7 degrees C, low temperature) on the low-light (75-85 micromol x m(-2) x s(-1)) tolerance of two Cucumis sativus cultivars (shade-susceptible Jinyan 2 and shade-tolerant Deltastar) seedling leaves in their photosynthesis were studied. The results showed that under low light, the SPAD, net photosynthesis rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), water use efficiency (WUE), actual photochemical efficiency of PS II in the light (phi(PS II)), and photochemical quenching of chlorophyll fluorescence (q(p)) of cucumber leaves decreased, with the decrement getting more with decreasing temperature, while the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities were in adverse. During the recovery process after low-light stress relieved, the parameters of gas exchange and chlorophyll fluorescence of the leaves recovered gradually, and the recovery of some gas exchange parameters lagged to that of chlorophyll fluorescence parameters. Under low light, the lower the temperature, the more damage the photosynthesis apparatus suffered, and the lesser tolerance to low light the cucumber leaves had in their photosynthesis. During the low temperature and low light treatment period, the decrease of Pn, phi(PS II), and q(p) was more obvious for Jinyan 2 than for Deltastar; and during the relief period, the recovery of these parameters was slower for Jinyan 2 than for Deltastar. It was indicated that Jinyan 2 had weaker tolerance to low temperature and/or low light in its photosynthesis than Deltastar.

[Reproduction,genotype identification and evaluation of APP/PS1 transgenic mice].

PubMed

Tan, Long; Li, Hai-Qiang; Li, Yi-Bo; Liu, Wei; Pang, Wei; Jiang, Yu-Gang

2018-02-08

To identify the genotype of (APP/PS1) transgenic mice and evaluate the changing of cognitive and behavioral fu nctions, provide an effective animal model for the Alzheimer's disease (AD) research. Male APP/PS1 transgenic mice mated with female APP/PS1 transgenic mice, and the genotype of their filial mice was identified by PCR. The APP +/PS1 + mice were assigned into AD model group (AD group, n =8), and the APP/PS1 mice were assigned into control group (CT group, n =8). The Morris water maze test was carried out to detect the capacity of learning and memory of mice. After that, the mice were sacrificed and the brain tissues were sampled and stained by HE and congo red for the pathological examination. ①A APP/PS1 genome DNA about 360 bp size was detected. The methods of feeding and breeding were successful to attain APP/PS1 transgenic mice.②Statistical significance was found in the differences of the capacity of learning and memory between 7-month-old APP/PS1 positive mice and negative mice ( P <0.05).③The results of HE stain showed that the structure and cellular morphology of hippocampus of AD mice were obviously abnormal. The results of congo red stain showed that positive amyloid plaque was observed in brains of AD mice. APP/PS1 transgenic mice present typical symptoms and behaviors of Alzheimer's disease. The transgenic mouse is an effective tool for the research and prevention of AD.

Isolation and Molecular Characterization of a Model Antagonistic Pseudomonas aeruginosa Divulging In Vitro Plant Growth Promoting Characteristics.

PubMed

Uzair, Bushra; Kausar, Rehana; Bano, Syeda Asma; Fatima, Sammer; Badshah, Malik; Habiba, Ume; Fasim, Fehmida

2018-01-01

The use of microbial technologies in agriculture is currently expanding quite rapidly with the identification of new bacterial strains, which are more effective in promoting plant growth. In the present study 18 strains of Pseudomonas were isolated from soil sample of Balochistan coastline. Among isolated Pseudomonas strains four designated as SP19, SP22, PS24, and SP25 exhibited biocontrol activities against phytopathogenic fungi, that is, Rhizopus microsporus, Fusarium oxysporum, Aspergillus niger, Alternaria alternata, and Penicillium digitatum ; PS24 identified as Pseudomonas aeruginosa by 16srRNA gene bank accession number EU081518 was selected on the basis of its antifungal activity to explore its potential as plant growth promotion. PS24 showed multiple plant growth promoting attributes such as phosphate solubilization activity, indole acetic acid (IAA), siderophore, and HCN production. In order to determine the basis for antifungal properties, antibiotics were extracted from King B broth of PS24 and analyzed by TLC. Pyrrolnitrin antibiotic was detected in the culture of strain PS24. PS24 exhibited antifungal activities found to be positive for hydrogen cyanide synthase Hcn BC gene. Sequencing of gene of Hcn BC gene of strain PS24 revealed 99% homology with the Pseudomonas aeruginosa strain PA01 . The sequence of PS24 had been submitted in gene bank accession number KR605499. Ps. aeruginosa PS24 with its multifunctional biocontrol possessions can be used to bioprotect the crop plants from phytopathogens.

Optical and electrical measurement of energy transfer between nanocrystalline quantum dots and photosystem I.

PubMed

Jung, Hyeson; Gulis, Galina; Gupta, Subhadra; Redding, Kevin; Gosztola, David J; Wiederrecht, Gary P; Stroscio, Michael A; Dutta, Mitra

2010-11-18

In the natural photosynthesis process, light harvesting complexes (LHCs) absorb light and pass excitation energy to photosystem I (PSI) and photosystem II (PSII). In this study, we have used nanocrystalline quantum dots (NQDs) as an artificial LHC by integrating them with PSI to extend their spectral range. We have performed photoluminescence (PL) and ultrafast time-resolved absorption measurements to investigate this process. Our PL experiments showed that emission from the NQDs is quenched, and the fluorescence from PSI is enhanced. Transient absorption and bleaching results can be explained by fluorescence resonance energy transfer (FRET) from the NQDs to the PSI. This nonradiative energy transfer occurs in ∼6 ps. Current-voltage (I-V) measurements on the composite NQD-PSI samples demonstrate a clear photoresponse.

System compliance dictates the effect of composite filler content on polymerization shrinkage stress.

PubMed

Wang, Zhengzhi; Chiang, Martin Y M

2016-04-01

The effect of filler content in dental restorative composites on the polymerization shrinkage stress (PS) is not straightforward and has caused much debate in the literature. Our objective in this study was to clarify the PS/filler content relationship based on analytical and experimental approaches, so that guidelines for materials comparison in terms of PS and clinical selection of dental composites with various filler content can be provided. Analytically, a simplified model based on linear elasticity was utilized to predict PS as a function of filler content under various compliances of the testing system, a cantilever beam-based instrument used in this study. The predictions were validated by measuring PS of composites synthesized using 50/50 mixtures of two common dimethacrylate resins with a variety of filler contents. Both experiments and predictions indicated that the influence of filler content on the PS highly depended on the compliance of the testing system. Within the clinic-relevant range of compliances and for the specific sample configuration tested, the PS increased with increasing filler content at low compliance of instrument, while increasing the compliance caused the effect of filler content on the PS to gradually diminish. Eventually, at high compliance, the PS inverted and decreased with increasing filler content. This compliance-dependent effect of filler content on PS suggests: (1) for materials comparison in terms of PS, the specific compliance at which the comparison being done should always be reported and (2) clinically, composites with relatively lower filler content could be selected for such cavities with relatively lower compliance (e.g. a Class-I cavity with thick tooth walls or the basal part in a cavity) and vice versa in order to reduce the final PS. Published by Elsevier Ltd.

Comparison of Sonar Discrimination by an Echolocating Dolphin and a Counterpropagation Neural Network

DTIC Science & Technology

1992-09-01

having a Roitblat et al. (1989) used a counterpropaga- half-power width of 264 ps. A width of 264 ps was tion network to emulate a d6lphin performing a...46- iis sfo M ) t ( ,, -oore. P.U S., Roitblat , HL., Penner, RN., and 0 44 0+ 0; 0 00 -06 -04 4)2 Nachtl lli, P,, (11191). Neural Networks 4, 11t1 J...wAtt tHIC5NtG:5tttlt~tN WmmI Roitblat , H L , Monte, P.W.I-, Nachtlgall. P It.i ~ Penner, •,H_, and Au. V.W.L (1949), Intern D i~tiby +---- Wig 1

The role of ultraviolet-adaptation of a marine diatom in photoenhanced toxicity of acridine.

PubMed

Wiegman, Saskia; Barranguet, Christiane; Spijkerman, Elly; Kraak, Michiel Harm Steven; Admiraal, Wim

2003-03-01

Cultures of the marine diatom Phaeodactylum tricornutum were grown under laboratory light with a different fraction of ultraviolet radiation (UV) to study the potential role of photoadaptation in determining the sensitivity to photoenhanced toxicity of acridine. In short-term experiments, a higher acridine concentration was needed to inhibit the photosynthetic electron flux, monitored with chlorophyll a fluorescence, in algae exposed to fluorescent light (low UV) than to mercury light (high UV), consistent with the expected role of UV. The two types of light in long-term exposures led to changes in the pigment composition and photosystem I (PS I) to photosystem II (PS II) stoichiometry to optimize the utilization of fluorescent and mercury light. Despite the adaptation of the photosynthetic apparatus to a small fraction of UV, long-term exposure to mercury light did show a constant sensitivity of the photosynthetic efficiency of P. tricornutum to the phototoxic acridine. It is concluded that the prime receptor of photoenhanced toxicity may be unrelated to the photosynthetic machinery.

Utilization of xylose as a carbon source for mixotrophic growth of Scenedesmus obliquus.

PubMed

Yang, Suling; Liu, Guijun; Meng, Youting; Wang, Ping; Zhou, Sijing; Shang, Hongzhong

2014-11-01

Mixotrophic cultivation is one potential mode for microalgae production, and an economically acceptable and environmentally sustainable organic carbon source is essential. The potential use of xylose for culturing Scenedesmus obliquus in a mixotrophic mode and physiological features of xylose-grown S. obliquus were studied. S. obliquus had a certain xylose tolerance, and was capable of utilizing xylose for growth. At a xylose concentration of 4gL(-1), the maximal cell density was 2.2gL(-1), being 2.9-fold of that under photoautotrophic condition and arriving to the level of mixotrophic growth using 4gL(-1) glucose. No changes in cellular morphology of the cells grown with or without xylose were detected. Fluorescence emission from photosystem II (PS II) relative to photosystem I (PS I) was decreased in mixotrophic cells, implying that the PSII activity was decreased. The biomass lipid content was enhanced and carbohydrate concentration was decreased, in relation to photoautotrophic controls. Copyright © 2014 Elsevier Ltd. All rights reserved.

Small particle size lipid emulsions, satiety and energy intake in lean men.

PubMed

Chan, Y K; Budgett, S C; MacGibbon, A K; Quek, S Y; Kindleysides, S; Poppitt, S D

2017-02-01

Lipid emulsions have been proposed to suppress hunger and food intake. Whilst there is no consensus on optimal structural properties or mechanism of action, small particle size (small-PS) stable emulsions may have greatest efficacy. Fabuless®, a commercial lipid emulsion reported in some studies to decrease energy intake (EI), is a small-PS, 'hard' fat emulsion comprising highly saturated palm oil base (PS, 82nm). To determine whether small-PS dairy lipid emulsions can enhance satiety, firstly, we investigated 2 'soft' fat dairy emulsions generated using dairy and soy emulsifying agents (PS, 114nm and 121nm) and a non-emulsified dairy control. Secondly, we investigated a small-PS palmolein based 'hard' fat emulsion (fractionated palm oil, PS, 104nm) and non-emulsified control. This was a 6 arm, randomized, cross-over study in 18 lean men, with test lipids delivered in a breakfast meal: (i) Fabuless® emulsion (F EM ); (ii) dairy emulsion with dairy emulsifier (DE DE ); (iii) dairy emulsion with soy lecithin emulsifier (DE SE ); (iv) dairy control (DC ON ); (v) palmolein emulsion with dairy emulsifier (PE DE ); (vi) palmolein control (PC ON ). Participants rated postprandial appetite sensations using visual analogue scales (VAS), and ad libitum energy intake (EI) was measured at a lunch meal 3.5h later. Dairy lipid emulsions did not significantly alter satiety ratings or change EI relative to dairy control (DE DE , 4035kJ; DE SE , 3904kJ; DC ON , 3985kJ; P>0.05) nor did palm oil based emulsion relative to non-emulsified control (PE DE, 3902 kJ; PC ON, 3973kJ; P>0.05). There was no evidence that small-PS dairy lipid emulsions or commercial Fabuless altered short-term appetite or food intake in lean adults. Copyright © 2016. Published by Elsevier Inc.

Removing user fees for health services: A multi-epistemological perspective on access inequities in Senegal.

PubMed

Mladovsky, Philipa; Ba, Maymouna

2017-09-01

Plan Sésame (PS) is a user fee exemption policy launched in 2006 to provide free access to health services to Senegalese citizens aged 60 and over. Analysis of a large household survey evaluating PS echoes findings of other studies showing that user fee removal can be highly inequitable. 34 semi-structured interviews and 19 focus group discussions with people aged 60 and over were conducted in four regions in Senegal (Dakar, Diourbel, Matam and Tambacounda) over a period of six months during 2012. They were analysed to identify underlying causes of exclusion from/inclusion in PS and triangulated with the household survey. The results point to three steps at which exclusion occurs: (i) not being informed about PS; (ii) not perceiving a need to use health services under PS; and (iii) inability to access health services under PS, despite having the information and perceived need. We identify lay explanations for exclusion at these different steps. Some lay explanations point to social exclusion, defined as unequal power relations. For example, poor access to PS was seen to be caused by corruption, patronage, poverty, lack of social support, internalised discrimination and adverse incorporation. Other lay explanations do not point to social exclusion, for example: poor implementation; inadequate funding; high population demand; incompetent bureaucracy; and PS as a favour or moral obligation to friends or family. Within a critical realist paradigm, we interpret these lay explanations as empirical evidence for the presence of the following hidden underlying causal mechanisms: lacking capabilities; mobilisation of institutional bias; and social closure. However, social constructionist perspectives lead us to critique this paradigm by drawing attention to contested health, wellbeing and corruption discourses. These differences in interpretation lead to subsequent differential policy recommendations. This demonstrates the need for the adoption of a "multi-epistemological" perspective in studies of health inequity and social exclusion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Association between cell-derived microparticles and adverse events in patients with nonpulsatile left ventricular assist devices.

PubMed

Nascimbene, Angelo; Hernandez, Ruben; George, Joggy K; Parker, Anita; Bergeron, Angela L; Pradhan, Subhashree; Vijayan, K Vinod; Civitello, Andrew; Simpson, Leo; Nawrot, Maria; Lee, Vei-Vei; Mallidi, Hari R; Delgado, Reynolds M; Dong, Jing Fei; Frazier, O H

2014-05-01

Continuous-flow left ventricular assist devices (LVADs) expose blood cells to high shear stress, potentially resulting in the production of microparticles that express phosphatidylserine (PS+) and promote coagulation and inflammation. In this prospective study, we attempted to determine whether PS+ microparticle levels correlate with clinical outcomes in LVAD-supported patients. We enrolled 20 patients undergoing implantation of the HeartMate II LVAD (Thoratec Corp, Pleasanton, CA) and 10 healthy controls who provided reference values for the microparticle assays. Plasma was collected before LVAD implantation, at discharge, at the 3-month follow-up, and when an adverse clinical event occurred. We quantified PS+ microparticles in the plasma using flow cytometry. During the study period, 8 patients developed adverse clinical events: ventricular tachycardia storm in 1, non-ST-elevation myocardial infarction in 2, arterial thrombosis in 2, gastrointestinal bleeding in 2, and stroke in 3. Levels of PS+ microparticles were higher in patients at baseline than in healthy controls (2.11% ± 1.26% vs 0.69% ± 0.46%, p = 0.007). After LVAD implantation, patient PS+ microparticle levels increased to 2.39% ± 1.22% at discharge and then leveled to 1.97% ± 1.25% at the 3-month follow-up. Importantly, levels of PS+ microparticles were significantly higher in patients who developed an adverse event than in patients with no events (3.82% ± 1.17% vs 1.57% ± 0.59%, p < 0.001), even though the 2 patient groups did not markedly differ in other clinical and hematologic parameters. Our results suggest that an elevation of PS+ microparticle levels may be associated with adverse clinical events. Thus, measuring PS+ microparticle levels in LVAD-supported patients may help identify patients at increased risk for adverse events. Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

Direct Measurement of the Photoelectric Response Time of Bacteriorhodopsin via Electro-Optic Sampling

PubMed Central

Xu, J.; Stickrath, A. B.; Bhattacharya, P.; Nees, J.; Váró, G.; Hillebrecht, J. R.; Ren, L.; Birge, R. R.

2003-01-01

The photovoltaic signal associated with the primary photochemical event in an oriented bacteriorhodopsin film is measured by directly probing the electric field in the bacteriorhodopsin film using an ultrafast electro-optic sampling technique. The inherent response time is limited only by the laser pulse width of 500 fs, and permits a measurement of the photovoltage with a bandwidth of better than 350 GHz. All previous published studies have been carried out with bandwidths of 50 GHz or lower. We observe a charge buildup with an exponential formation time of 1.68 ± 0.05 ps and an initial decay time of 31.7 ps. Deconvolution with a 500-fs Gaussian excitation pulse reduces the exponential formation time to 1.61 ± 0.04 ps. The photovoltaic signal continues to rise for 4.5 ps after excitation, and the voltage profile corresponds well with the population dynamics of the K state. The origin of the fast photovoltage is assigned to the partial isomerization of the chromophore and the coupled motion of the Arg-82 residue during the primary event. PMID:12885657

In vitro near-infrared imaging of natural secondary caries.

PubMed

Simon, Jacob C; Lucas, Seth; Lee, Robert; Darling, Cynthia L; Staninec, Michal; Vanderhobli, Ram; Pelzner, Roger; Fried, Daniel

2015-02-24

Secondary caries stands as the leading reason for the failure of composite restorations and dentists spend more time replacing existing restorations than placing new ones. Current clinical strategies, and even modern visible light methods designed to detect decay, lack the sensitivity to distinguish incipient lesions, are confounded by staining on the surface and within the tooth, or are limited to detecting decay on the tooth surface. Near-IR (NIR) imaging methods, such as NIR reflectance and transillumination imaging, and optical coherence tomography are promising strategies for imaging secondary caries. Wavelengths longer than 1300-nm avoid interference from stain and exploit the greater transparency of sound enamel and dental composites, to provide increased contrast with demineralized tissues and improved imaging depth. The purpose of this study was to determine whether NIR transillumination (λ=1300-nm) and NIR cross-polarized reflectance (λ=1500-1700-nm) images can serve as reliable indicators of demineralization surrounding composite restorations. Twelve composite margins (n=12) consisting of class I, II & V restorations were chosen from ten extracted teeth. The samples were imaged in vitro using NIR transillumination and reflectance, polarization sensitive optical coherence tomography (PS-OCT) and a high-magnification digital visible light microscope. Samples were serially sectioned into 200- μ m slices for histological analysis using polarized light microscopy (PLM) and transverse microradiography (TMR). The results presented demonstrate the utility of NIR light for detecting recurrent decay and suggest that NIR images could be a reliable screening tool used in conjunction with PS-OCT for the detection and diagnosis of secondary caries.

In-vitro near-infrared imaging of natural secondary caries

NASA Astrophysics Data System (ADS)

Simon, Jacob C.; Lucas, Seth; Lee, Robert; Darling, Cynthia L.; Staninec, Michal; Vanderhobli, Ram; Pelzner, Roger; Fried, Daniel

2015-02-01

Secondary caries stands as the leading reason for the failure of composite restorations and dentists spend more time replacing existing restorations than placing new ones. Current clinical strategies, and even modern visible light methods designed to detect decay, lack the sensitivity to distinguish incipient lesions, are confounded by staining on the surface and within the tooth, or are limited to detecting decay on the tooth surface. Near-IR (NIR) imaging methods, such as NIR reflectance and transillumination imaging, and optical coherence tomography are promising strategies for imaging secondary caries. Wavelengths longer than 1300-nm avoid interference from stain and exploit the greater transparency of sound enamel and dental composites, to provide increased contrast with demineralized tissues and improved imaging depth. The purpose of this study was to determine whether NIR transillumination (λ=1300-nm) and NIR crosspolarized reflectance (λ=1500-1700-nm) images can serve as reliable indicators of demineralization surrounding composite restorations. Twelve composite margins (n=12) consisting of class I, II and V restorations were chosen from ten extracted teeth. The samples were imaged in vitro using NIR transillumination and reflectance, polarization sensitive optical coherence tomography (PS-OCT) and a high-magnification digital visible light microscope. Samples were serially sectioned into 200-μm slices for histological analysis using polarized light microscopy (PLM) and transverse microradiography (TMR). The results presented demonstrate the utility of NIR light for detecting recurrent decay and suggest that NIR images could be a reliable screening tool used in conjunction with PS-OCT for the detection and diagnosis of secondary caries.

Silicon Dioxide Planarization: Impacts on Optical Coatings for High Energy Laser

NASA Astrophysics Data System (ADS)

Day, Travis E.

The work of this thesis is devoted to examining the impact of silicon dioxide (silica or SiO2) planarization on the optical properties and laser damage resistance of thin-film coatings. SiO2 planarization is a process to smooth out fluence limiting nodular defects within multilayer coatings for high-energy laser applications. Mitigating these defects will improve the power handling abilities and improve the lifetime of laser coatings. Presented here is a combination of work with the aim of evaluating the optical and laser damage properties of SiO2 planarization within single layers, bilayers, and multilayers. As compared to control (non-planarized) samples, a 2-3x increase in the thin-film absorption, which decreases with post-process annealing, was discovered for SiO2 planarized samples. This suggests that planarization creates oxygen-related defects which can be annealed out and little impurity implantation. Investigations of laser damage resistance were carried out at lambda = 1030nm and pulse durations of tau = 220ps and 9ps. The laser damage of single and bilayer coatings is known to be dependent on the substrate-coating interface and this is further evidenced within this thesis. This is because the effects of planarization are masked by the extrinsic laser damage processes within the single and bilayers. Slight change (< 15%) in the laser induced damage threshold (LIDT) at 220ps and 9ps was observed for planarized single and bilayers. Depending on coating design, post-process annealing was shown to increase the LIDT by 10% to 75% at 220ps and 10% to 45% at 9ps. Although the fused silica substrate surface LIDT was shown to follow the √tau pulse scaling law for pulses above 10ps, the single and bilayer coatings do not follow this pulse scaling. The divergence from the √tau pulse scaling on the coatings suggests a variation in the laser damage initiation mechanisms between 220ps and 9ps. Multilayer high-reflecting (HR) mirrors with varying planarization design were also damage tested. A 6-7 J/cm2 LIDT, with 220ps, was observed for HR coatings with SiO2 planarization layers within high electric-field areas within the coating. However, SiO2 planarization at the substrate-coating interface, where the electric-field is minimal, and control (non-planarized) was shown to have a LIDT of 63 +/- 1.2 J/cm 2 and 21.5 +/- 0.5 J/cm2 for 220ps, respectively. At 9ps, the LIDT varied less than 90% difference between the various planarization designs. The substrate-coating planarization multilayer and control coating had an equal LIDT of 9.6 +/- .3 J/cm2 at 9ps.

Comparative analysis of thermal behavior, isothermal crystallization kinetics and polymorphism of palm oil fractions.

PubMed

Zhang, Xia; Li, Lin; Xie, He; Liang, Zhili; Su, Jianyu; Liu, Guoqin; Li, Bing

2013-01-15

Thermal behavior of palm stearin (PS) and palm olein (PO) was explored by monitoring peak temperature transitions by differential scanning calorimetry (DSC). The fatty acid composition (FAC), isothermal crystallization kinetics studied by pulsed Nuclear Magnetic Resonance (pNMR) and isothermal microstructure were also compared. The results indicated that the fatty acid composition had an important influence on the crystallization process. PS and PO both exhibited more multiple endotherms than exotherms which showed irregular peak shapes. An increasing in cooling rate, generally, was associated with an increase in peak size. Application of the Avaimi equation to isothermal crystallization of PS and PO revealed different nucleation and growth mechanisms based on the Avrami exponents. PS quickly reached the end of crystallization because of more saturated triacylglycerol (TAG). The Avrami index of PS were the same as PO under the same isothermal condition at lower temperatrue, indicating that the crystallization mechanism of the two samples based on super-cooling state were the same. According to the polarized light microscope (PLM) images, crystal morphology of PS and PO was different. With the temperature increased, the structure of crystal network of both PS and PO gradually loosened.

psRNATarget: a plant small RNA target analysis server (2017 release).

PubMed

Dai, Xinbin; Zhuang, Zhaohong; Zhao, Patrick Xuechun

2018-04-30

Plant regulatory small RNAs (sRNAs), which include most microRNAs (miRNAs) and a subset of small interfering RNAs (siRNAs), such as the phased siRNAs (phasiRNAs), play important roles in regulating gene expression. Although generated from genetically distinct biogenesis pathways, these regulatory sRNAs share the same mechanisms for post-translational gene silencing and translational inhibition. psRNATarget was developed to identify plant sRNA targets by (i) analyzing complementary matching between the sRNA sequence and target mRNA sequence using a predefined scoring schema and (ii) by evaluating target site accessibility. This update enhances its analytical performance by developing a new scoring schema that is capable of discovering miRNA-mRNA interactions at higher 'recall rates' without significantly increasing total prediction output. The scoring procedure is customizable for the users to search both canonical and non-canonical targets. This update also enables transmitting and analyzing 'big' data empowered by (a) the implementation of multi-threading chunked file uploading, which can be paused and resumed, using HTML5 APIs and (b) the allocation of significantly more computing nodes to its back-end Linux cluster. The updated psRNATarget server has clear, compelling and user-friendly interfaces that enhance user experiences and present data clearly and concisely. The psRNATarget is freely available at http://plantgrn.noble.org/psRNATarget/.

Evaluation of the effectiveness of semen storage and sperm purification methods for spermatozoa transcript profiling.

PubMed

Mao, Shihong; Goodrich, Robert J; Hauser, Russ; Schrader, Steven M; Chen, Zhen; Krawetz, Stephen A

2013-10-01

Different semen storage and sperm purification methods may affect the integrity of isolated spermatozoal RNA. RNA-Seq was applied to determine whether semen storage methods (pelleted vs. liquefied) and somatic cell lysis buffer (SCLB) vs. PureSperm (PS) purification methods affect the quantity and quality of sperm RNA. The results indicate that the method of semen storage does not markedly impact RNA profiling whereas the choice of purification can yield significant differences. RNA-Seq showed that the majority of mitochondrial and mid-piece associated transcripts were lost after SCLB purification, which indicated that the mid-piece of spermatozoa may have been compromised. In addition, the number of stable transcript pairs from SCLB-samples was less than that from the PS samples. This study supports the view that PS purification better maintains the integrity of spermatozoal RNAs.

Use of Flood Seasonality in Pooling-Group Formation and Quantile Estimation: An Application in Great Britain

NASA Astrophysics Data System (ADS)

Formetta, Giuseppe; Bell, Victoria; Stewart, Elizabeth

2018-02-01

Regional flood frequency analysis is one of the most commonly applied methods for estimating extreme flood events at ungauged sites or locations with short measurement records. It is based on: (i) the definition of a homogeneous group (pooling-group) of catchments, and on (ii) the use of the pooling-group data to estimate flood quantiles. Although many methods to define a pooling-group (pooling schemes, PS) are based on catchment physiographic similarity measures, in the last decade methods based on flood seasonality similarity have been contemplated. In this paper, two seasonality-based PS are proposed and tested both in terms of the homogeneity of the pooling-groups they generate and in terms of the accuracy in estimating extreme flood events. The method has been applied in 420 catchments in Great Britain (considered as both gauged and ungauged) and compared against the current Flood Estimation Handbook (FEH) PS. Results for gauged sites show that, compared to the current PS, the seasonality-based PS performs better both in terms of homogeneity of the pooling-group and in terms of the accuracy of flood quantile estimates. For ungauged locations, a national-scale hydrological model has been used for the first time to quantify flood seasonality. Results show that in 75% of the tested locations the seasonality-based PS provides an improvement in the accuracy of the flood quantile estimates. The remaining 25% were located in highly urbanized, groundwater-dependent catchments. The promising results support the aspiration that large-scale hydrological models complement traditional methods for estimating design floods.

Pectoralis-serratus interfascial plane block vs thoracic paravertebral block for unilateral radical mastectomy with axillary evacuation.

PubMed

Hetta, Diab Fuad; Rezk, Khalid Mohammed

2016-11-01

The aim of this study was to evaluate the analgesic efficacy and safety of pectoralis-serratus interfascial plane block in comparison with thoracic paravertebral block for postmastectomy pain. A prospective randomized controlled study. Tertiary center, university hospital. Sixty-four adult women, American Society of Anesthesiologists physical status classes I, II, and III, scheduled for unilateral modified radical mastectomy with axillary evacuation. Patients were randomized to receive either pectoralis-serratus interfascial plane block, PS group (n=32), or thoracic paravertebral block, PV group (n=32). Twenty-four-hour morphine consumption and the time to rescue analgesic were recorded. The pain intensity evaluated by visual analog scale (VAS) score at 0, 2, 4, 8, 16, and 24hours postoperatively was also recorded. The median (interquartile range) postoperative 24-hour morphine consumption was significantly increased in PS group in comparison to PV group (PS vs PV), 20 mg (16-23 mg) vs 12 mg (10-14 mg) (P<.001). The median postoperative time to first analgesic request was significantly shorter in PS group compared to PV group (PS, 6 hours [5-7 hours], vs PV, 11 hours [9-13 hours]) (P<.001). The intensity of pain was low in both groups in VAS 0, 2, and 4hours postoperatively. However, there was significant reduction in VAS in PV group compared to PS group at 8, 16, and 24hours postoperatively. Pectoralis-serratus interfascial plane block was safe and easy to perform and decreased intensity of postmastectomy pain, but it was inferior to thoracic paravertebral block. Copyright © 2016 Elsevier Inc. All rights reserved.

Treatment of Grade II and III Actinic Keratosis Lesions with a Film-Forming Medical Device Containing Sunscreen/Piroxicam 0.8% and a Retinoic Acid/Glycolic Gel: A Pilot Trial.

PubMed

Puviani, Mario; Milani, Massimo

2018-05-31

Lesion and field-targeted treatments of actinic keratosis (AK) are commonly indicated for grade I and II type lesions. Grade III lesions are in general more difficult to treat. A film-forming medical device containing piroxicam 0.8% and sunscreen (SPF 50+) (PS) has been shown to be effective in the treatment of grade I and II AK lesions. Topical and oral retinoids have been utilized in AK and non-melanoma skin cancers. Topical glycolic acid promotes keratolysis and stimulates collagen synthesis for repair and skin rejuvenation and could be useful in AK treatment strategies. A gel containing retinoid acid (0.02%) and glycolic acid (4%) (RC) is commercially available. The objective of the study was to evaluate the efficacy and local tolerability of a combined treatment approach with PS and RC in subjects with multiple grade II and III AK lesions. Twenty-two subjects (16 males and 6 females; mean age 68 years) with more than five AK lesions were enrolled after obtaining their informed consent in a 3-month trial. PS cream was applied twice daily every day and RC gel was applied twice daily for 2 consecutive days every week. The primary endpoint was the evolution of the AK mean number from baseline to the end of the trial. Secondary endpoints were the thickness of the target lesion (expressed in mm 3 ) and the erythema score (hemoglobin content), evaluated using a standardized computer-based image acquisition analysis system (Anthera 3D). At baseline, the mean (SD) lesion number was 7.7 (3) for grade II and 1.4 (1) for grade III AK. At the end of the study, a significant (P = 0.001) reduction was observed for both grade II (- 81%; from 7.7 to 1.5) and grade III (- 22%) lesions. Six grade III lesions out of 31 (20%), presented at baseline, completely disappeared at month 3. For grade III lesions, a significant mean thickness reduction of 51% was observed at month 3. The erythema score (all lesions) was reduced by 70%. Four patients out of 22 (18%) were completely free of AK lesions at month 3. No severe side effects were reported. In this exploratory trial, a combined treatment with a cream containing piroxicam and sunscreen and a retinoic/glycolic gel was associated with a substantial reduction of both grade II and III AK lesions with good local tolerability. Cantabria Labs Difa Cooper.

Ketones prevent synaptic dysfunction induced by mitochondrial respiratory complex inhibitors

PubMed Central

Kim, Do Young; Vallejo, Johana; Rho, Jong M

2010-01-01

Abstract Ketones have previously shown beneficial effects in models of neurodegenerative disorders, particularly against associated mitochondrial dysfunction and cognitive impairment. However, evidence of a synaptic protective effect of ketones remains lacking. We tested the effects of ketones on synaptic impairment induced by mitochondrial respiratory complex (MRC) inhibitors using electrophysiological, reactive oxygen species (ROS) imaging and biochemical techniques. MRC inhibitors dose-dependently suppressed both population spike (PS) and field potential amplitudes in the CA1 hippocampus. Pre-treatment with ketones strongly prevented changes in the PS, whereas partial protection was seen in the field potential. Rotenone (Rot; 100 nmol/L), a MRC I inhibitor, suppressed synaptic function without altering ROS levels and PS depression by Rot was unaffected by antioxidants. In contrast, antioxidant-induced PS recovery against the MRC II inhibitor 3-nitropropionic acid (3-NP; 1 mmol/L) was similar to the synaptic protective effects of ketones. Ketones also suppressed ROS generation induced by 3-NP. Finally, ketones reversed the decreases in ATP levels caused by Rot and 3-NP. In summary, our data demonstrate that ketones can preserve synaptic function in CA1 hippocampus induced by MRC dysfunction, likely through an antioxidant action and enhanced ATP generation. PMID:20374433

In vitro kinematic measurements of the patellar tendon in two different types of posterior-stabilized total knee arthroplasties.

PubMed

Zhu, Zhonglin; Ding, Hui; Dang, Xiao; Tang, Jing; Zhou, Yixin; Wang, Guangzhi

2010-01-01

Fixed-bearing posterior-stabilized (PS) total knee arthroplasty (TKA) has been used in Asian countries for several years, but few studies have investigated differences in the kinematic properties of the patellar tendon after standard PS TKA as compared to high-flex PS TKA. To quantify the in vitro three-dimensional (3D) kinematics of the patellar tendon during passive high flexion and full extension before and after two different types of PS TKAs. Six fresh-frozen cadaveric knees were tested under the following conditions: the unaltered state, status-post traditional PS prostheses (Simth-nephew GENESIS II) replacement, and status-post high-flexion PS prostheses replacement. The soft tissue around the knee and the quadriceps muscle were preserved, then tested under the load of a specific weight in an Oxford knee rig. We designed a specialized rigid body with four active markers fixed to each bone to track the 3D passive motion of the cadaveric knees. Flexion and extension was controlled by the knee rig and captured by an Optotrak Certus high precision optical tracking system. The attachment sites of the patellar tendon were registered as virtual markers to calculate the 3D kinematics. The patellar tendon of the unaltered knee and both TKA knees showed similar deformation. We found the length of the patellar tendon changed significantly during a motion from full extension to 30°, but there was no significant change in length while undergoing a motion from 30° to full flexion. Both the sagittal plane and coronal plane angles of the patellar tendon decreased after PS TKAs. There was no significant difference in patellar tendon kinematics between the two types of PS TKAs. We believe the changes observed in the sagittal plane and coronal plane angles of the patellar tendon after PS TKAs may influence the extensor mechanism and be an important cause of patella-femoral complications. These data may be used to assess patella-femoral complications after surgery so as to improve the design of high-flexion TKAs for Asians and achieve long-term stability.

Size-dependent accumulation of particles in lysosomes modulates dendritic cell function through impaired antigen degradation

PubMed Central

Seydoux, Emilie; Rothen-Rutishauser, Barbara; Nita, Izabela M; Balog, Sandor; Gazdhar, Amiq; Stumbles, Philip A; Petri-Fink, Alke; Blank, Fabian; von Garnier, Christophe

2014-01-01

Introduction Nanosized particles may enable therapeutic modulation of immune responses by targeting dendritic cell (DC) networks in accessible organs such as the lung. To date, however, the effects of nanoparticles on DC function and downstream immune responses remain poorly understood. Methods Bone marrow–derived DCs (BMDCs) were exposed in vitro to 20 or 1,000 nm polystyrene (PS) particles. Particle uptake kinetics, cell surface marker expression, soluble protein antigen uptake and degradation, as well as in vitro CD4+ T-cell proliferation and cytokine production were analyzed by flow cytometry. In addition, co-localization of particles within the lysosomal compartment, lysosomal permeability, and endoplasmic reticulum stress were analyzed. Results The frequency of PS particle–positive CD11c+/CD11b+ BMDCs reached an early plateau after 20 minutes and was significantly higher for 20 nm than for 1,000 nm PS particles at all time-points analyzed. PS particles did not alter cell viability or modify expression of the surface markers CD11b, CD11c, MHC class II, CD40, and CD86. Although particle exposure did not modulate antigen uptake, 20 nm PS particles decreased the capacity of BMDCs to degrade soluble antigen, without affecting their ability to induce antigen-specific CD4+ T-cell proliferation. Co-localization studies between PS particles and lysosomes using laser scanning confocal microscopy detected a significantly higher frequency of co-localized 20 nm particles as compared with their 1,000 nm counterparts. Neither size of PS particle caused lysosomal leakage, expression of endoplasmic reticulum stress gene markers, or changes in cytokines profiles. Conclusion These data indicate that although supposedly inert PS nanoparticles did not induce DC activation or alteration in CD4+ T-cell stimulating capacity, 20 nm (but not 1,000 nm) PS particles may reduce antigen degradation through interference in the lysosomal compartment. These findings emphasize the importance of performing in-depth analysis of DC function when developing novel approaches for immune modulation with nanoparticles. PMID:25152619

Toward Personalized Medicine: Using Cardiomyocytes Differentiated From Urine-Derived Pluripotent Stem Cells to Recapitulate Electrophysiological Characteristics of Type 2 Long QT Syndrome.

PubMed

Jouni, Mariam; Si-Tayeb, Karim; Es-Salah-Lamoureux, Zeineb; Latypova, Xenia; Champon, Benoite; Caillaud, Amandine; Rungoat, Anais; Charpentier, Flavien; Loussouarn, Gildas; Baró, Isabelle; Zibara, Kazem; Lemarchand, Patricia; Gaborit, Nathalie

2015-09-01

Human genetically inherited cardiac diseases have been studied mainly in heterologous systems or animal models, independent of patients' genetic backgrounds. Because sources of human cardiomyocytes (CMs) are extremely limited, the use of urine samples to generate induced pluripotent stem cell-derived CMs would be a noninvasive method to identify cardiac dysfunctions that lead to pathologies within patients' specific genetic backgrounds. The objective was to validate the use of CMs differentiated from urine-derived human induced pluripotent stem (UhiPS) cells as a new cellular model for studying patients' specific arrhythmia mechanisms. Cells obtained from urine samples of a patient with long QT syndrome who harbored the HERG A561P gene mutation and his asymptomatic noncarrier mother were reprogrammed using the episomal-based method. UhiPS cells were then differentiated into CMs using the matrix sandwich method.UhiPS-CMs showed proper expression of atrial and ventricular myofilament proteins and ion channels. They were electrically functional, with nodal-, atrial- and ventricular-like action potentials recorded using high-throughput optical and patch-clamp techniques. Comparison of HERG expression from the patient's UhiPS-CMs to the mother's UhiPS-CMs showed that the mutation led to a trafficking defect that resulted in reduced delayed rectifier K(+) current (IKr). This phenotype gave rise to action potential prolongation and arrhythmias. UhiPS cells from patients carrying ion channel mutations can be used as novel tools to differentiate functional CMs that recapitulate cardiac arrhythmia phenotypes. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Nondestructive assessment of dentin demineralization using polarization sensitive optical coherence tomography after exposure to fluoride and laser irradiation

PubMed Central

Manesh, Saman K.; Darling, Cynthia L.; Fried, Daniel

2009-01-01

Previous studies have demonstrated that polarization sensitive optical coherence tomography (PS-OCT) can be used to image natural and artificial caries in dentin. The purpose of this study was to measure non-destructively the severity of artificial caries lesions in dentin and determine the efficacy of intervention with anti-caries agents including fluoride and lasers. Although several studies have assessed the utility of PS-OCT to image caries lesions in enamel and to quantify the lesion severity, only a few studies have focused on lesions in dentin. In this study images of artificial dentin lesions on extracted human teeth were acquired with PS-OCT. Before exposure to an artificial demineralizing solution, three incisions were made on the sample surfaces using either Er:YAG, Nd:YAG (λ=355-nm), or TEA CO2 lasers and selected areas were treated with topical fluoride to create six unique treatment areas for each of the three laser conditions investigated. The integrated reflectivity and depth of demineralization were calculated for each of the six areas on each sample using the PS-OCT images. Polarized light microscopy (PLM) and transverse microradiography (TMR) were used to measure lesion severity on histological thin sections for comparison. PS-OCT successfully measured the inhibition of demineralization by topical fluoride. Laser irradiation was not particularly effective in increasing or decreasing the rate of dentin demineralization. PLM and TMR corroborated those results. This study demonstrates that PS-OCT can be used to measure demineralization on dentin surfaces and determine the degree of inhibition of demineralization by anti-caries agents. PMID:19283826

Assessment of dentin remineralization with PS-OCT

NASA Astrophysics Data System (ADS)

Manesh, Saman K.; Darling, Cynthia L.; Fried, Daniel

2009-02-01

Previous studies have demonstrated that polarization sensitive optical coherence tomography (PS-OCT) can be used to image natural root caries lesions, measure non-destructively the severity of dentin demineralization and determine the efficacy of intervention with anti-caries agents including fluoride and lasers. The objective of this study was to determine if PS-OCT could be used to nondestructively measure the formation of a layer of remineralized dentin on the surface of dentin lesions after exposure to a remineralization solution. In this study images of artificial dentin lesions on extracted human teeth were acquired using PS-OCT after exposure to an artificial demineralizing solution at pH 4.9 for six days and after subsequent exposure to a remineralizing solution at pH 7.0 for 20 days. Polarized light microscopy and microradiography were used to examine histological thin sections from the samples for comparison. PS-OCT successfully measured the formation of a layer of increased mineral content near the lesion surface. PLM and TMR corroborated those results. This study demonstrates the potential use of PS-OCT for the nondestructive measurement of the remineralization of dentin surfaces.

Attitudes of palliative home care physicians towards palliative sedation at home in Italy.

PubMed

Mercadante, Sebastiano; Masedu, Francesco; Mercadante, Alessandro; Marinangeli, Franco; Aielli, Federica

2017-05-01

Information about the attitudes towards palliative sedation (PS) at home is limited. The aim of this survey was to assess the attitudes of palliative care physicians in Italy regarding PS at home. A questionnaire was submitted to a sample of palliative care physicians, asking information about their activity and attitudes towards PS at home. This is a survey of home care physicians in Italy who were involved in end-of-life care decisions at home. One hundred and fifty participants responded. A large heterogeneity of home care organizations that generate some problems was found. Indications, intention and monitoring of PS seem to be appropriate, although some cultural and logistic conditions were limiting the use of PS. Specialized home care physicians are almost involved to start PS at home. Midazolam was seldom available at home and opioids were more frequently used. These data should prompt health care agencies to make a minimal set of drugs easily available for home care. Further research is necessary to compare attitudes in countries with different sociocultural profiles.

Detection of picosecond electrical pulses using the intrinsic Franz{endash}Keldysh effect

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

Lampin, J. F.; Desplanque, L.; Mollot, F.

2001-06-25

We report time-resolved measurements of ultrafast electrical pulses propagating on a coplanar transmission line using the intrinsic Franz{endash}Keldysh effect. A low-temperature-grown GaAs layer deposited on a GaAs substrate allows generation and also detection of ps pulses via electroabsorption sampling (EAS). This all-optical method does not require any external sampling probe. A typical rise time of 1.1 ps has been measured. EAS is a good candidate for use in THz characterization of ultrafast devices. {copyright} 2001 American Institute of Physics.

Blast Noise Prediction. Volume II. BNOISE 3.2 Computer Program Description and Program Listing.

DTIC Science & Technology

1981-03-01

tttim itit) k cii he sCli h I Apptif 4\\1111,1C’ I Lin ~Ist I Itis is tj ’it. hi ilti Ituitph inlI N’ skiLl I ink, hi k I i e II it,~ 11it I Mi...to which the point (XMIN,YMIN) will correspond SCLE Card cc 1 SCLI - PS( A L Format (A4,2X,G8.3) where. PSCALF (col 7-14t is the plotter scale factor

Time interval measurement device based on surface acoustic wave filter excitation, providing 1 ps precision and stability.

PubMed

Panek, Petr; Prochazka, Ivan

2007-09-01

This article deals with the time interval measurement device, which is based on a surface acoustic wave (SAW) filter as a time interpolator. The operating principle is based on the fact that a transversal SAW filter excited by a short pulse can generate a finite signal with highly suppressed spectra outside a narrow frequency band. If the responses to two excitations are sampled at clock ticks, they can be precisely reconstructed from a finite number of samples and then compared so as to determine the time interval between the two excitations. We have designed and constructed a two-channel time interval measurement device which allows independent timing of two events and evaluation of the time interval between them. The device has been constructed using commercially available components. The experimental results proved the concept. We have assessed the single-shot time interval measurement precision of 1.3 ps rms that corresponds to the time of arrival precision of 0.9 ps rms in each channel. The temperature drift of the measured time interval on temperature is lower than 0.5 ps/K, and the long term stability is better than +/-0.2 ps/h. These are to our knowledge the best values reported for the time interval measurement device. The results are in good agreement with the error budget based on the theoretical analysis.

Rapid Analysis of Corni fructus Using Paper Spray-Mass Spectrometry.

PubMed

Guo, Yuan; Gu, Zhixin; Liu, Xuemei; Liu, Jingjing; Ma, Ming; Chen, Bo; Wang, Liping

2017-07-01

Paper spray-mass spectrometry (PS-MS) is a kind of ambient MS technique for the rapid analysis of samples. Corni fructus has been widely used in traditional Chinese compound preparations and healthy food. However, a number of counterfeits of Corni fructus, such as Crataegi fructus, Lycii fructus, and grape skin are illegally sold in crude herb markets. Therefore, the development of a rapid and high-throughput quality evaluation method is important for ensuring the effectiveness and safety of the crude materials of Corni fructus. To develop PS-MS chemical profiles and a semi-quantitative method of Corni fructus for quality assessment and control, and species distinction of Corni fructus. Both positive and negative ion PS-MS chemical profiles were constructed for species distinction. The statistical analysis of the chemical profiles was accomplished by principal component analysis (PCA). Rapid semi-quantitative analysis of loganin and morroniside in the extracts of Corni fructus were accomplished by PS-MS. The profiles of the Corni fructus and Crataegi fructus samples were clearly clustered into two categories. The limit of quantification (LOQ) in the semi-quantitative analysis was 6 μg/mL and 5.6 μg/mL for loganin and morroniside, respectively. PS-MS is a simple, rapid, and high-throughput method for the quality control and species distinction of Corni fructus. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Influence of pH, layer charge location and crystal thickness distribution on U(VI) sorption onto heterogeneous dioctahedral smectite.

PubMed

Guimarães, Vanessa; Rodríguez-Castellón, Enrique; Algarra, Manuel; Rocha, Fernando; Bobos, Iuliu

2016-11-05

The UO2(2+) adsorption on smectite (samples BA1, PS2 and PS3) with a heterogeneous structure was investigated at pH 4 (I=0.02M) and pH 6 (I=0.2M) in batch experiments, with the aim to evaluate the influence of pH, layer charge location and crystal thickness distribution. Mean crystal thickness distribution of smectite crystallite used in sorption experiments range from 4.8nm (sample PS2), to 5.1nm (sample PS3) and, to 7.4nm (sample BA1). Smaller crystallites have higher total surface area and sorption capacity. Octahedral charge location favor higher sorption capacity. The sorption isotherms of Freundlich, Langmuir and SIPS were used to model the sorption experiments. The surface complexation and cation exchange reactions were modeled using PHREEQC-code to describe the UO2(2+) sorption on smectite. The amount of UO2(2+) adsorbed on smectite samples decreased significantly at pH 6 and higher ionic strength, where the sorption mechanism was restricted to the edge sites of smectite. Two binding energy components at 380.8±0.3 and 382.2±0.3eV, assigned to hydrated UO2(2+) adsorbed by cation exchange and by inner-sphere complexation on the external sites at pH 4, were identified after the U4f7/2 peak deconvolution by X-photoelectron spectroscopy. Also, two new binding energy components at 380.3±0.3 and 381.8±0.3eV assigned to AlOUO2(+) and SiOUO2(+) surface species were observed at pH 6. Copyright © 2016 Elsevier B.V. All rights reserved.

A Measurement of the Lifetime of the Λ b Baryon with the CDF Detector at the Tevatron Run II

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

Unverhau, Tatjana Alberta Hanna

2004-12-01

In March 2001 the Tevatron accelerator entered its Run II phase, providing colliding proton and anti-proton beams with an unprecedented center-of-mass energy of 1.96 TeV. The Tevatron is currently the only accelerator to produce Λ b baryons, which provides a unique opportunity to measure the properties of these particles. This thesis presents a measurement of the mean lifetime of the Λ b baryon in the semileptonic channel Λmore » $$0\\atop{b}$$ → Λ$$+\\atop{c}$$ μ - $$\\bar{v}$$ μ. In total 186 pb -1 of data were used for this analysis, collected with the CDF detector between February 2002 and September 2003. To select the long-lived events from b-decays, the secondary vertex trigger was utilized. This significant addition to the trigger for Run II allows, for the first time, the selection of events with tracks displaced from the primary interaction vertex at the second trigger level. After the application of selection cuts this trigger sample contains approximately 991 Λ b candidates. To extract the mean lifetime of Λ b baryons from this sample, they transverse decay length of the candidates is fitted with an unbinned maximum likelihood fit under the consideration of the missing neutrino momentum and the bias introduced by the secondary vertex trigger. The mean lifetime of the Λ b is measured to be τ = 1.29 ± 0.11(stat.) ± 0.07(syst.) ps equivalent to a mean decay length of cτ = 387 ± 33(stat.) ± 21 (syst.) μm.« less

Prevalence of obesity and abdominal obesity from four to 16 years old children living in the Mexico-USA border.

PubMed

Bacardí-Gascón, Montserrat; Jones, Elizabeth G; Jiménez-Cruz, Arturo

2013-01-01

The prevalence of obesity among Mexicans is alarming in both the child and adult populations. The objective of this study was to determine the levels of overweight, obesity and abdominal obesity in pre-school (PS), elementary (ES), and middle high (MHS) public school children from Tijuana. From February to April of 2011, a bietapic random sample was selected by cluster method of 30 PS, 30 ES, and 30 MHS children. And a sample of 30 groups for each level was chosen. Twenty elementary teachers and eight graduate students were trained at one central location on how to take anthropometric measurements using a portable scale, a stadiometer, and a measuring tape to determine weight, height, and waist circumference. Body Mass Index values were computed and compared to age/gender BMI percentiles according to WHO criteria. Waist circumference for-age at the 90th percentile from NHANES III (Mexican-American) was used to define abdominal obesity. The sample was composed of 646 PS children, 961 ES children, and 1,095 MHS children. Their ages ranged from 4- 16 years. Results showed an overall prevalence of overweight and obesity in younger than 5y preschool children (> 2 SD) of 23.1%, in ≥ 5 y PS (> 1 SD) of 33.8%, in ES children of 46.3%, and in MHS children of 41.9%. Abdominal obesity in PS children was 18%, in ES children was 16.7%, and in MHS children was 15.2%. These results warrant immediate and comprehensive actions to prevent a critical public health problem in Mexico. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

A Personal Appraisal of the MIBiol Courses in Entomology and Plant Pathology at Wolverhampton Polytechnic, 1967-71

ERIC Educational Resources Information Center

Ayerst, G.; Gower, A. M.

1972-01-01

Article provides brief description of two microbiology courses at the college level which have multiple characteristics. Course I provides instruction based on papers in biology and in a special subject. Course II is devoted entirely to the special subject. (PS)

Japanese Americans During World War II.

ERIC Educational Resources Information Center

Irons, Peter; Masugi, Ken

1986-01-01

The arguments in favor of and against monetary redress for survivors of America's wartime internment camps are presented. Pro-redress arguments emphasize the injustices done the victims. Anti-redress arguments focus on the duties for citizenship and the reasonable actions politicians might have concluded were necessary to win the war. (PS)

Ultra-broadband infrared pump-probe spectroscopy using synchrotron radiation and a tuneable pump.

PubMed

Carroll, Lee; Friedli, Peter; Lerch, Philippe; Schneider, Jörg; Treyer, Daniel; Hunziker, Stephan; Stutz, Stefan; Sigg, Hans

2011-06-01

Synchrotron infrared sources have become popular mainly because of their excellent broadband brilliance, which enables spectroscopically resolved spatial-mapping of stationary objects at the diffraction limit. In this article we focus on an often-neglected further advantage of such sources - their unique time-structure - to bring such broadband spectroscopy to the time domain, for studying dynamic phenomenon down to the 100 ps limit. We describe the ultra-broadband (12.5 to 1.1 μm) Fourier transform pump-probe setup, for condensed matter transmission- and reflection-spectroscopy, installed at the X01DC infrared beam-line of the Swiss Light Source (SLS). The optical pump consists of a widely tuneable 100 ps 1 kHz laser system, covering 94% of the 16 to 1.1 μm range. A thorough description of the system is given, including (i) the vector-modulator providing purely electronic tuning of the pump-probe overlap up to 1 ms with sub-ps time resolution, (ii) the 500 MHz data acquisition system interfaced with the experimental physics and industrial control system (EPICS) based SLS control system for consecutive pulse sampling, and (iii) the step-scan time-slice Fourier transform scheme for simultaneous recording of the dual-channel pumped, un-pumped, and difference spectra. The typical signal/noise ratio of a single interferogram in a 100 ps time slice is 300 (measured during one single 140 s TopUp period). This signal/noise ratio is comparable to that of existing gated Globar pump-probe Fourier transform spectroscopy, but brings up to four orders of magnitude better time resolution. To showcase the utility of broadband pump-probe spectroscopy, we investigate a Ge-on-Si material system similar to that in which optically pumped direct-gap lasing was recently reported. We show that the mid-infrared reflection-spectra can be used to determine the optically injected carrier density, while the mid- and near-infrared transmission-spectra can be used to separate the strong pump-induced absorption and inversion processes present at the direct-gap energy. © 2011 American Institute of Physics

Nuclear spin polarized H and D by means of spin-exchange optical pumping

NASA Astrophysics Data System (ADS)

Stenger, Jörn; Grosshauser, Carsten; Kilian, Wolfgang; Nagengast, Wolfgang; Ranzenberger, Bernd; Rith, Klaus; Schmidt, Frank

1998-01-01

Optically pumped spin-exchange sources for polarized hydrogen and deuterium atoms have been demonstrated to yield high atomic flow and high electron spin polarization. For maximum nuclear polarization the source has to be operated in spin temperature equilibrium, which has already been demonstrated for hydrogen. In spin temperature equilibrium the nuclear spin polarization PI equals the electron spin polarization PS for hydrogen and is even larger than PS for deuterium. We discuss the general properties of spin temperature equilibrium for a sample of deuterium atoms. One result are the equations PI=4PS/(3+PS2) and Pzz=PSṡPI, where Pzz is the nuclear tensor polarization. Furthermore we demonstrate that the deuterium atoms from our source are in spin temperature equilibrium within the experimental accuracy.

Cyclotron resonance spectroscopy in a high mobility two dimensional electron gas using characteristic matrix methods.

PubMed

Hilton, David J

2012-12-31

We develop a new characteristic matrix-based method to analyze cyclotron resonance experiments in high mobility two-dimensional electron gas samples where direct interference between primary and satellite reflections has previously limited the frequency resolution. This model is used to simulate experimental data taken using terahertz time-domain spectroscopy that show multiple pulses from the substrate with a separation of 15 ps that directly interfere in the time-domain. We determine a cyclotron dephasing lifetime of 15.1 ± 0.5 ps at 1.5 K and 5.0 ± 0.5 ps at 75 K.

Positron annihilation lifetime and photoluminescence studies on single crystalline ZnO

NASA Astrophysics Data System (ADS)

Sarkar, A.; Chakrabarti, Mahuya; Ray, S. K.; Bhowmick, D.; Sanyal, D.

2011-04-01

The room temperature positron annihilation lifetime for single crystalline ZnO has been measured as 164 ± 1 ps. The single component lifetime value is very close to but higher than the theoretically predicted value of ~ 154 ps. Photoluminescence study (at 10 K) indicates the presence of hydrogen and other defects, mainly acceptor related, in the crystal. Defects related to a lower open volume than zinc vacancies, presumably a complex with two hydrogen atoms, are the major trapping sites in the sample. The bulk positron lifetime in ZnO is expected to be a little less than 164 ps.

Positron annihilation lifetime and photoluminescence studies on single crystalline ZnO.

PubMed

Sarkar, A; Chakrabarti, Mahuya; Ray, S K; Bhowmick, D; Sanyal, D

2011-04-20

The room temperature positron annihilation lifetime for single crystalline ZnO has been measured as 164 ± 1 ps. The single component lifetime value is very close to but higher than the theoretically predicted value of ~154 ps. Photoluminescence study (at 10 K) indicates the presence of hydrogen and other defects, mainly acceptor related, in the crystal. Defects related to a lower open volume than zinc vacancies, presumably a complex with two hydrogen atoms, are the major trapping sites in the sample. The bulk positron lifetime in ZnO is expected to be a little less than 164 ps.

Effects of Zn Deficiency and Bicarbonate on the Growth and Photosynthetic Characteristics of Four Plant Species

PubMed Central

Zhao, Kuan; Wu, Yanyou

2017-01-01

Calcareous soils are characterized by low nutrient contents, high bicarbonate (HCO3−) content, and high alkalinity. The effects of HCO3− addition under zinc-sufficient (+Zn) and zinc-deficient (−Zn) conditions on the growth and photosynthetic characteristics of seedlings of two Moraceae species (Broussonetia papyrifera and Morus alba) and two Brassicaceae species (Orychophragmus violaceus and Brassica napus) were investigated. These four species were hydroponically grown in nutrient solution with 0 mM Zn (−Zn) or 0.02 mM Zn (+Zn) and 0 mM or 10 mM HCO3−. The photosynthetic response to HCO3− treatment, Zn deficiency, or both varied according to plant species. Of the four species, Broussonetia papyrifera showed the best adaptability to Zn deficiency for both the 0 mM and 10 mM HCO3− treatments due to its strong growth and minimal inhibition of photosynthesis and photosystem II (PS II). Brassica napus was sensitive to Zn deficiency, HCO3− treatment, or both as evidenced by the considerable inhibition of photosynthesis and high PS II activity. The results indicated different responses of various plant species to Zn deficiency and excess HCO3−. Broussonetia papyrifera was shown to have potential as a pioneer species in karst regions. PMID:28076430

Pathways of energy transfer in LHCII revealed by room-temperature 2D electronic spectroscopy.

PubMed

Wells, Kym L; Lambrev, Petar H; Zhang, Zhengyang; Garab, Gyözö; Tan, Howe-Siang

2014-06-21

We present here the first room-temperature 2D electronic spectroscopy study of energy transfer in the plant light-harvesting complex II, LHCII. Two-dimensional electronic spectroscopy has been used to study energy transfer dynamics in LHCII trimers from the chlorophyll b Qy band to the chlorophyll a Qy band. Observing cross-peak regions corresponding to couplings between different excitonic states reveals partially resolved fine structure at the exciton level that cannot be isolated by pump-probe or linear spectroscopy measurements alone. Global analysis of the data has been performed to identify the pathways and time constants of energy transfer. The measured waiting time (Tw) dependent 2D spectra are found to be composed of 2D decay-associated spectra with three timescales (0.3 ps, 2.3 ps and >20 ps). Direct and multistep cascading pathways from the high-energy chlorophyll b states to the lowest-energy chlorophyll a states have been resolved occurring on time scales of hundreds of femtoseconds to picoseconds.

Clinical features and prognosis of a sample of patients with trisomy 13 (Patau syndrome) from Brazil.

PubMed

Petry, Patrícia; Polli, Janaina B; Mattos, Vinícius F; Rosa, Rosana C M; Zen, Paulo R G; Graziadio, Carla; Paskulin, Giorgio A; Rosa, Rafael F M

2013-06-01

Trisomy 13 or Patau syndrome (PS) is a chromosomal disorder characterized by a well known presentation of multiple congenital anomalies. Our objective was to determine the clinical features and prognosis observed in a sample of patients with PS. The series was composed of patients with diagnosis of PS consecutively evaluated by a Clinical Genetics Service from a reference hospital of southern Brazil, in the period between 1975 and 2012. Statistical analysis was performed using PEPI program (version 4.0), with two-tailed Fisher's exact test for comparison of frequencies (P<0.05). The sample consisted of 30 patients, 60% male, median age at first evaluation of 9 days. Full trisomy of chromosome 13 was the main cytogenetic alteration (73%). The major clinical findings included: cryptorchidism (78%), abnormal auricles (77%), congenital heart defects (76%), polydactyly (63%), microphthalmia (60%) and micrognathia (50%). Four patients (13%) simultaneously had micro/anophthalmia, oral clefts and polydactyly. Some findings were only observed in our sample and included, among others, preauricular tags (10%), duplication of the hallux (3%) and spots following the lines of Blaschko (3%). Mosaicism (20% of cases) had a statistically significant association only with absence of cryptorchidism. The median of survival was 26 days. Patients with and without mosaicism had similar median of survival. Our findings, in agreement with the literature, show that the anomalies in patients with PS can be quite variable, sometimes even atypical. There is no pathognomonic finding, which may make the early identification of these patients challenging. Copyright © 2013 Wiley Periodicals, Inc.

Electron gun jitter effects on beam bunching

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

Liu, M. S.; Iqbal, M., E-mail: muniqbal.chep@pu.edu.pk; Centre for High Energy Physics, University of the Punjab, Lahore 45590

For routine operation of Beijing Electron Positron Collider II (BEPCII) linac, many factors may affect the beam bunching process directly or indirectly. We present the measurements and analyses of the gun timing jitter, gun high voltage jitter, and beam energy at the exit of the standard acceleration section of the linac quantitatively. Almost 80 mV and more than 200 ps of gun high voltage and time jitters have ever been measured, respectively. It was analyzed that the gun timing jitter produced severe effects on beam energy than the gun high voltage jitter, if the timing jitter exceeded 100 ps whichmore » eventually deteriorates both the beam performance and the injection rate to the storage ring.« less

In vivo sampling of Verteporfin uptake in pancreas cancer xenograft models: comparison of surface, oral, and interstitial measurements

NASA Astrophysics Data System (ADS)

Isabelle, Martin; O'Hara, Julia A.; Samkoe, Kimberley S.; Hoopes, P. Jack; Mosse, Sandy; Pereira, Stephen; Hasan, Tayyaba; Pogue, Brian W.

2010-02-01

Photodynamic therapy (PDT) mediated with Verteporfin is being investigated as a pancreatic cancer treatment in the cases for non-surgical candidates. Tissue response to PDT is based on a number of parameters including photosensitizer (PS) dose, light dose and time interval between light application and PS injection. In this study, PS uptake and distribution in animal leg muscle, oral cavity tissues, pancreas and tumor was measured in vivo using light-induced fluorescence spectroscopy (LIFS) via an Aurora Optics Inc. PDT fluorescence dosimeter. An orthotopic pancreatic cancer model (AsPC-1) was implanted in SCID mice and treated with the PS. Probe measurements were made using a surface probe and an interstitial needle probe before and up to one hour after intravenous tail vein injection of the PS. The study demonstrated that it is possible to correlate in-vivo LIFS measurements of the PS uptake in the pancreas with measurements taken from the oral cavity indicating that light dosimetry of PDT of the pancreas can be ascertained from the LIFS measurements in the oral cavity. These results emphasize the importance of light dosimetry in improving the therapeutic outcome of PDT through light dose adaptation to the relative in situ tissue PS concentration.

Qualitative assessment to determine internal and external factors influencing the origin of styrene oligomers pollution by polystyrene plastic in coastal marine environments.

PubMed

Kwon, Bum Gun; Chung, Seon-Yong; Park, Seung-Shik; Saido, Katsuhiko

2018-03-01

The objective of this study is to investigate the qualitative contribution of internal and external factors of the area contaminated by polystyrene (PS) in coastal marine environments. This study is based on the extensive results of monitoring the styrene oligomers (SOs) present in sand and seawater samples along various coastlines of the Pacific Ocean. Here, anthropogenic SOs is derived from PS during manufacture and use, and can provide clues about the origin of SOs by PS pollution. The monitoring results showed that, if the concentration of SOs in water is higher than those concentrations in beach sand, this area could be affected by PS plastic caused by an external factor. On the other hand, if the concentration of SOs is higher in the beach sand, the region can be mainly influenced by PS plastic derived from its own area. Unlike the case of an external factor, in this case (internal influence), it is possible to take policy measures of the area itself for the PS plastic problem. Thus, this study is motivated by the need of policy measures to establish a specific alternative to the problems of PS plastic pollution in ocean environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Method to calibrate phase fluctuation in polarization-sensitive swept-source optical coherence tomography

NASA Astrophysics Data System (ADS)

Lu, Zenghai; Kasaragod, Deepa K.; Matcher, Stephen J.

2011-07-01

We present a phase fluctuation calibration method for polarization-sensitive swept-source optical coherence tomography (PS-SS-OCT) using continuous polarization modulation. The method uses a low-voltage broadband polarization modulator driven by a synchronized sinusoidal burst waveform rather than an asynchronous waveform, together with the removal of the global phases of the measured Jones matrices by the use of matrix normalization. This makes it possible to average the measured Jones matrices to remove the artifact due to the speckle noise of the signal in the sample without introducing auxiliary optical components into the sample arm. This method was validated on measurements of an equine tendon sample by the PS-SS-OCT system.

Evaluation of Federal Aviation Administration Engine Exhaust Sampling Rake.

DTIC Science & Technology

1977-06-01

Engine exit total pressure - Pt7 " High turbine discharge temperature - Tt65,6 . Engine exit total temperature - Tt7 - Burner pressure - Ps4 0 Total...illustrated by Figure 22, a plot of Ps4 /Pt7 (expansion thru the turbine) vs. EPR (Pt7/Pt2). This plot indicates that the ECCP rake has no measurable effect on

Observations of local interstellar Mg I and Mg II

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

Bruhweiler, F.C.; Oegerle, W.; Weiler, E.

1984-11-01

Copernicus and IUE observations of 5 stars within 50 pc of the Sun were combined to study the ionization of magnesium in the Local Interstellar Medium (LISM). The high resolution Copernicus spectrometer was used to detect interstellar MG I 2852 in the spectra of alpha Gru, alpha Eri, and alpha Lyr, while placing upper limits on Mg I in the spectra of alpha CMa and alpha PsA. Observations of Mg II 2795, 2802 for these stars were also obtained with IUE and Copernicus. The column densities of Mg I and Mg II are used to place constraints on the temperaturemore » of the LISM.« less

Observations of Local Interstellar Mg I and Mg II

NASA Technical Reports Server (NTRS)

Bruhweiler, F. C.; Oegerle, W.; Weiler, E.; Stencel, R. E.; Kondo, Y.

1984-01-01

Copernicus and IUE observations of 5 stars within 50 pc of the Sun were combined to study the ionization of magnesium in the local interstellar medium (LISM). The high resolution Copernicus spectrometer was used to detect interstellar MG I 2852 in the spectra of alpha Gru, alpha Eri, and alpha Lyr, while placing upper limits on Mg I in the spectra of alpha CMa and alpha PsA. Observations of Mg II 2795, 2802 for these stars were also obtained with IUE and Copernicus. The column densities of Mg I and Mg II are used to place constraints on the temperature of the LISM.

[The Mediating Role of Parenting Self-Efficacy on Parenting Stress and Quality of Life in Parents of Young Children With Developmental Delay].

PubMed

Sun, Yi; Wu, Wei-Wen; Lin, Kuan-Chia; Chen, Jo-Lin

2016-10-01

Previous studies indicate that parents of developmentally delayed children have higher parenting stress (PS) and lower quality of life (QoL) than parents of healthy children. Parenting self-efficacy (PSE) may mediate the effects of PS on the QoL of parents. The present study explores the mediating role of PSE between PS and the QoL of parents of developmentally delayed children and compares the differences in several variables between fathers and mothers. A cross-sectional research design was used to study a sample of 70 parent dyads. Instruments used were the Basic Information Form, Parenting Stress Index Short Form (PSI-SF), Parenting Self-efficacy Scale (PSE Scale), and World Health Organization Quality of Life-BREF Taiwan version (WHOQOL-BREF). (1) Participants had a moderate level of QoL, PS, and PSE. (2) The PS of participants was significantly and negatively correlated with both QoL and PSE while their PSE was significantly and positively correlated with QoL. (3) The PSE of the fathers completely mediated the effects of PS on their QoL (p < .001), accounting for 62.2% of observed variation, while the PSE of the mothers partially mediated the effects of PS on their QoL (p < .05), accounting for 59.5% of observed variation. PSE was identified as the mediator between PS and QoL in both fathers and mothers. The PSE of the fathers completely mediated the effect of PS on QoL, while the PSE of the mothers partially mediated the effect of PS on QoL. Further research that explores the factors that affect the QoL of parents and then uses the results to develop interventions to enhance the PSE of parents, especially fathers, is recommended.

Direct Comparison of Surface and Bulk Relaxation of PS - A Temperature Dependent Study

NASA Astrophysics Data System (ADS)

Wu, Wen-Li; Sambasivan, Sharadha; Wang, Chia-Ying; Genzer, Jan; Fischer, Daniel A.

2005-03-01

Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy was used to measure simultaneously the relaxation rates of polystyrene (PS) molecules at the free surface and in the bulk. The samples were uniaxially oriented at room temperature via a modified cold rolling process. The density of the oriented samples as determined by liquid immersion technique is identical to that of bulk PS. At temperatures below its bulk glass transition temperature the rate of surface and bulk chain relaxation was monitored by measuring the partial-electron yield (PEY) and the fluorescence NEXAFS yields (FS), respectively, both parallel and perpendicular to the stretching direction. The decay rate of the dichroic ratios from both PEY and FY at various temperatures was taken as a measure of the relaxation rate of surface and bulk molecules respectively. In addition, the decay rate of the optical birefringence was also measured to provide an independent measure of the bulk relaxation. Relaxation of PS chains was found to occur faster on the surface relative to the bulk. The magnitude of the surface glass transition temperature suppression over the bulk was estimated to be 18 C based on the measured temperature dependence of the relaxation rates.

Global styrene oligomers monitoring as new chemical contamination from polystyrene plastic marine pollution.

PubMed

Kwon, Bum Gun; Koizumi, Koshiro; Chung, Seon-Yong; Kodera, Yoichi; Kim, Jong-Oh; Saido, Katsuhiko

2015-12-30

Polystyrene (PS) plastic marine pollution is an environmental concern. However, a reliable and objective assessment of the scope of this problem, which can lead to persistent organic contaminants, has yet to be performed. Here, we show that anthropogenic styrene oligomers (SOs), a possible indicator of PS pollution in the ocean, are found globally at concentrations that are higher than those expected based on the stability of PS. SOs appear to persist to varying degrees in the seawater and sand samples collected from beaches around the world. The most persistent forms are styrene monomer, styrene dimer, and styrene trimer. Sand samples from beaches, which are commonly recreation sites, are particularly polluted with these high SOs concentrations. This finding is of interest from both scientific and public perspectives because SOs may pose potential long-term risks to the environment in combination with other endocrine disrupting chemicals. From SOs monitoring results, this study proposes a flow diagram for SOs leaching from PS cycle. Using this flow diagram, we conclude that SOs are global contaminants in sandy beaches around the world due to their broad spatial distribution. Copyright © 2015 Elsevier B.V. All rights reserved.

Use of a polystyrene-divinylbenzene-based weakly acidic cation-exchange resin column and propionic acid as an eluent in ion-exclusion/adsorption chromatography of aliphatic carboxylic acids and ethanol in food samples.

PubMed

Mori, Masanobu; Hironaga, Takahiro; Kajiwara, Hiroe; Nakatani, Nobutake; Kozaki, Daisuke; Itabashi, Hideyuki; Tanaka, Kazuhiko

2011-01-01

We developed an ion-exclusion/adsorption chromatography (IEAC) method employing a polystyrene-divinylbenzene-based weakly acidic cation-exchange resin (PS-WCX) column with propionic acid as the eluent for the simultaneous determination of multivalent aliphatic carboxylic acids and ethanol in food samples. The PS-WCX column well resolved mono-, di-, and trivalent carboxylic acids in the acidic eluent. Propionic acid as the eluent gave a higher signal-to-noise ratio, and enabled sensitive conductimetric detection of analyte acids. We found the optimal separation condition to be the combination of a PS-WCX column and 20-mM propionic acid. Practical applicability of the developed method was confirmed by using a short precolumn with a strongly acidic cation-exchange resin in the H(+)-form connected before the separation column; this was to remove cations from food samples by converting them to hydrogen ions. Consequently, common carboxylic acids and ethanol in beer, wine, and soy sauce were successfully separated by the developed method.

K-band observations of boxy bulges - I. Morphology and surface brightness profiles

NASA Astrophysics Data System (ADS)

Bureau, M.; Aronica, G.; Athanassoula, E.; Dettmar, R.-J.; Bosma, A.; Freeman, K. C.

2006-08-01

In this first paper of a series on the structure of boxy and peanut-shaped (B/PS) bulges, Kn-band observations of a sample of 30 edge-on spiral galaxies are described and discussed. Kn-band observations best trace the dominant luminous galactic mass and are minimally affected by dust. Images, unsharp-masked images, as well as major-axis and vertically summed surface brightness profiles are presented and discussed. Galaxies with a B/PS bulge tend to have a more complex morphology than galaxies with other bulge types, more often showing centred or off-centred X structures, secondary maxima along the major-axis and spiral-like structures. While probably not uniquely related to bars, those features are observed in three-dimensional N-body simulations of barred discs and may trace the main bar orbit families. The surface brightness profiles of galaxies with a B/PS bulge are also more complex, typically containing three or more clearly separated regions, including a shallow or flat intermediate region (Freeman Type II profiles). The breaks in the profiles offer evidence for bar-driven transfer of angular momentum and radial redistribution of material. The profiles further suggest a rapid variation of the scaleheight of the disc material, contrary to conventional wisdom but again as expected from the vertical resonances and instabilities present in barred discs. Interestingly, the steep inner region of the surface brightness profiles is often shorter than the isophotally thick part of the galaxies, itself always shorter than the flat intermediate region of the profiles. The steep inner region is also much more prominent along the major-axis than in the vertically summed profiles. Similarly to other recent work but contrary to the standard `bulge + disc' model (where the bulge is both thick and steep), we thus propose that galaxies with a B/PS bulge are composed of a thin concentrated disc (a disc-like bulge) contained within a partially thick bar (the B/PS bulge), itself contained within a thin outer disc. The inner disc likely formed secularly through bar-driven processes and is responsible for the steep inner region of the surface brightness profiles, traditionally associated with a classic bulge, while the bar is responsible for the flat intermediate region of the surface brightness profiles and the thick complex morphological structures observed. Those components are strongly coupled dynamically and are formed mostly of the same (disc) material, shaped by the weak but relentless action of the bar resonances. Any competing formation scenario for galaxies with a B/PS bulge, which represent at least 45 per cent of the local disc galaxy population, must explain equally well and self-consistently the above morphological and photometric properties, the complex gas and stellar kinematics observed, and the correlations between them.

Detailed transient heme structures of Mb-CO in solution after CO dissociation: an X-ray transient absorption spectroscopic study.

PubMed

Stickrath, Andrew B; Mara, Michael W; Lockard, Jenny V; Harpham, Michael R; Huang, Jier; Zhang, Xiaoyi; Attenkofer, Klaus; Chen, Lin X

2013-04-25

Although understanding the structural dynamics associated with ligand photodissociation is necessary in order to correlate structure and function in biological systems, few techniques are capable of measuring the ultrafast dynamics of these systems in solution-phase at room temperature. We present here a detailed X-ray transient absorption (XTA) study of the photodissociation of CO-bound myoglobin (Fe(II)CO-Mb) in room-temperature aqueous buffer solution with a time resolution of 80 ps, along with a general procedure for handling biological samples under the harsh experimental conditions that transient X-ray experiments entail. The XTA spectra of (Fe(II)CO-Mb) exhibit significant XANES and XAFS alterations following 527 nm excitation, which remain unchanged for >47 μs. These spectral changes indicate loss of the CO ligand, resulting in a five-coordinate, domed heme, and significant energetic reorganization of the 3d orbitals of the Fe center. With the current experimental setup, each X-ray pulse in the pulse train, separated by ~153 ns, can be separately discriminated, yielding snapshots of the myoglobin evolution over time. These methods can be easily applied to other biological systems, allowing for simultaneous structural and electronic measurements of any biological system with both ultrafast and slow time resolutions, effectively mapping out all of the samples' relevant physiological processes.

k-Nearest neighbour local linear prediction of scalp EEG activity during intermittent photic stimulation.

PubMed

Erla, Silvia; Faes, Luca; Tranquillini, Enzo; Orrico, Daniele; Nollo, Giandomenico

2011-05-01

The characterization of the EEG response to photic stimulation (PS) is an important issue with significant clinical relevance. This study aims to quantify and map the complexity of the EEG during PS, where complexity is measured as the degree of unpredictability resulting from local linear prediction. EEG activity was recorded with eyes closed (EC) and eyes open (EO) during resting and PS at 5, 10, and 15 Hz in a group of 30 healthy subjects and in a case-report of a patient suffering from cerebral ischemia. The mean squared prediction error (MSPE) resulting from k-nearest neighbour local linear prediction was calculated in each condition as an index of EEG unpredictability. The linear or nonlinear nature of the system underlying EEG activity was evaluated quantifying MSPE as a function of the neighbourhood size during local linear prediction, and by surrogate data analysis as well. Unpredictability maps were obtained for each subject interpolating MSPE values over a schematic head representation. Results on healthy subjects evidenced: (i) the prevalence of linear mechanisms in the generation of EEG dynamics, (ii) the lower predictability of EO EEG, (iii) the desynchronization of oscillatory mechanisms during PS leading to increased EEG complexity, (iv) the entrainment of alpha rhythm during EC obtained by 10 Hz PS, and (v) differences of EEG predictability among different scalp regions. Ischemic patient showed different MSPE values in healthy and damaged regions. The EEG predictability decreased moving from the early acute stage to a stage of partial recovery. These results suggest that nonlinear prediction can be a useful tool to characterize EEG dynamics during PS protocols, and may consequently constitute a complement of quantitative EEG analysis in clinical applications. Copyright © 2010 IPEM. Published by Elsevier Ltd. All rights reserved.

psRNATarget: a plant small RNA target analysis server

PubMed Central

Dai, Xinbin; Zhao, Patrick Xuechun

2011-01-01

Plant endogenous non-coding short small RNAs (20–24 nt), including microRNAs (miRNAs) and a subset of small interfering RNAs (ta-siRNAs), play important role in gene expression regulatory networks (GRNs). For example, many transcription factors and development-related genes have been reported as targets of these regulatory small RNAs. Although a number of miRNA target prediction algorithms and programs have been developed, most of them were designed for animal miRNAs which are significantly different from plant miRNAs in the target recognition process. These differences demand the development of separate plant miRNA (and ta-siRNA) target analysis tool(s). We present psRNATarget, a plant small RNA target analysis server, which features two important analysis functions: (i) reverse complementary matching between small RNA and target transcript using a proven scoring schema, and (ii) target-site accessibility evaluation by calculating unpaired energy (UPE) required to ‘open’ secondary structure around small RNA’s target site on mRNA. The psRNATarget incorporates recent discoveries in plant miRNA target recognition, e.g. it distinguishes translational and post-transcriptional inhibition, and it reports the number of small RNA/target site pairs that may affect small RNA binding activity to target transcript. The psRNATarget server is designed for high-throughput analysis of next-generation data with an efficient distributed computing back-end pipeline that runs on a Linux cluster. The server front-end integrates three simplified user-friendly interfaces to accept user-submitted or preloaded small RNAs and transcript sequences; and outputs a comprehensive list of small RNA/target pairs along with the online tools for batch downloading, key word searching and results sorting. The psRNATarget server is freely available at http://plantgrn.noble.org/psRNATarget/. PMID:21622958

Changes in the vascular cell adhesion molecule-1, intercellular adhesion molecule-1 and c-reactive protein following administration of aqueous extract of piper sarmentosum on experimental rabbits fed with cholesterol diet

PubMed Central

2011-01-01

Background Inflammation process plays an important role in the development of atherosclerosis. Hypercholesterolemia is one of the major risk factors for atherosclerosis. The present study aimed to evaluate the effect of aqueous extract of Piper sarmentosum (P.s) on inflammatory markers like vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and C-reactive protein (CRP). Methods Forty two male New Zealand white rabbits were divided equally into seven groups; (i) C- control group fed normal rabbit chow (ii) CH- cholesterol diet (1%cholesterol) (iii) X1- 1% cholesterol with water extract of P.s (62.5 mg/kg) (iv) X2- 1% cholesterol with water extract of P.s (125 mg/kg (v) X3- 1% cholesterol with water extract of P.s (250 mg/kg) (vi) X4- 1% cholesterol with water extract of P.s (500 mg/kg) and (vii) SMV group fed with 1% cholesterol supplemented with simvistatin drug (1.2 mg/kg). All animals were treated for 10 weeks. Blood serum was taken for observing the inflammatory markers at the beginning and end of the experiment. Results Rabbits fed with 1% cholesterol diet (CH) showed significant increase in the level of VCAM-1, ICAM-1 and CRP compared to the C group. The levels of VCAM-1, ICAM-1 and CRP in the 1% cholesterol group and supplemented with P.s (500 mg/kg) were significantly reduced compared to the cholesterol group. Similar results were also reported with simvistatin group. Conclusion These results suggest that the supplementation of Piper sarmentosum extract could inhibit inflammatory markers which in turn could prevent atherosclerosis. PMID:21214952

Hierarchical active factors to band gap and nonlinear optical response in Ag-containing quaternary-chalcogenide compounds

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

Huang, Jun-ben; Xinjiang Key Laboratory of Electronic Information Material and Devices, Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences, 40-1 South Beijing Road, Urumqi 830011; Mamat, Mamatrishat, E-mail: mmtrxt@xju.edu.cn

In this research work, Ag-containing quaternary-chalcogenide compounds KAg{sub 2}TS{sub 4} (T=P, Sb) (I-II) and RbAg{sub 2}SbS{sub 4} (III) have been studied by means of Density Functional Theory as potential IR nonlinear optical materials. The origin of wide band gap, different optical anisotropy and large SHG response is explained via a combination of density of states, electronic density difference and bond population analysis. It is indicated that the different covalent interaction behavior of P-S and Sb-S bonds dominates the band gap and birefringence. Specifically, the Ag-containing chalcogenide compound KAg{sub 2}PS{sub 4} possesses wide band gap and SHG response comparable with thatmore » of AgGaS{sub 2}. By exploring the origin of the band gap and NLO response for compounds KAg{sub 2}TS{sub 4} (T=P, Sb), we found the determination factor to the properties is different, especially the roles of Ag-d orbitals and bonding behavior of P-S or Sb-S. Thus, the compounds KAg{sub 2}TS{sub 4} (T=P, Sb) and RbAg{sub 2}SbS{sub 4} can be used in infrared (IR) region. - Graphical abstract: Metal thiophosphates RbPbPS{sub 4} and KSbP{sub 2}S{sub 6} have a similar band gap with KAg{sub 2}PS{sub 4}. However, based on first principles calculated results it shown that KAg{sub 2}PS{sub 4} possesses wide band gap (3.02 eV) and relatively large SHG response. Display Omitted.« less

Modelling IRF8 Deficient Human Hematopoiesis and Dendritic Cell Development with Engineered iPS Cells.

PubMed

Sontag, Stephanie; Förster, Malrun; Qin, Jie; Wanek, Paul; Mitzka, Saskia; Schüler, Herdit M; Koschmieder, Steffen; Rose-John, Stefan; Seré, Kristin; Zenke, Martin

2017-04-01

Human induced pluripotent stem (iPS) cells can differentiate into cells of all three germ layers, including hematopoietic stem cells and their progeny. Interferon regulatory factor 8 (IRF8) is a transcription factor, which acts in hematopoiesis as lineage determining factor for myeloid cells, including dendritic cells (DC). Autosomal recessive or dominant IRF8 mutations occurring in patients cause severe monocytic and DC immunodeficiency. To study IRF8 in human hematopoiesis we generated human IRF8-/- iPS cells and IRF8-/- embryonic stem (ES) cells using RNA guided CRISPR/Cas9n genome editing. Upon induction of hematopoietic differentiation, we demonstrate that IRF8 is dispensable for iPS cell and ES cell differentiation into hemogenic endothelium and for endothelial-to-hematopoietic transition, and thus development of hematopoietic progenitors. We differentiated iPS cell and ES cell derived progenitors into CD141+ cross-presenting cDC1 and CD1c+ classical cDC2 and CD303+ plasmacytoid DC (pDC). We found that IRF8 deficiency compromised cDC1 and pDC development, while cDC2 development was largely unaffected. Additionally, in an unrestricted differentiation regimen, IRF8-/- iPS cells and ES cells exhibited a clear bias toward granulocytes at the expense of monocytes. IRF8-/- DC showed reduced MHC class II expression and were impaired in cytokine responses, migration, and antigen presentation. Taken together, we engineered a human IRF8 knockout model that allows studying molecular mechanisms of human immunodeficiencies in vitro, including the pathophysiology of IRF8 deficient DC. Stem Cells 2017;35:898-908. © 2017 The Authors Stem Cells published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Antimicrobial Photodynamic Therapy to Kill Gram-negative Bacteria

PubMed Central

Sperandio, Felipe F; Huang, Ying-Ying; Hamblin, Michael R

2013-01-01

Antimicrobial photodynamic therapy (PDT) or photodynamic inactivation (PDI) is a new promising strategy to eradicate pathogenic microorganisms such as Gram-positive and Gram-negative bacteria, yeasts and fungi. The search for new approaches that can kill bacteria but do not induce the appearance of undesired drug-resistant strains suggests that PDT may have advantages over traditional antibiotic therapy. PDT is a non-thermal photochemical reaction that involves the simultaneous presence of visible light, oxygen and a dye or photosensitizer (PS). Several PS have been studied for their ability to bind to bacteria and efficiently generate reactive oxygen species (ROS) upon photostimulation. ROS are formed through type I or II mechanisms and may inactivate several classes of microbial cells including Gram-negative bacteria such as Pseudomonas aeruginosa, which are typically characterized by an impermeable outer cell membrane that contains endotoxins and blocks antibiotics, dyes, and detergents, protecting the sensitive inner membrane and cell wall. This review covers significant peer-reviewed articles together with US and World patents that were filed within the past few years and that relate to the eradication of Gram-negative bacteria via PDI or PDT. It is organized mainly according to the nature of the PS involved and includes natural or synthetic food dyes; cationic dyes such as methylene blue and toluidine blue; tetrapyrrole derivatives such as phthalocyanines, chlorins, porphyrins, chlorophyll and bacteriochlorophyll derivatives; functionalized fullerenes; nanoparticles combined with different PS; other formulations designed to target PS to bacteria; photoactive materials and surfaces; conjugates between PS and polycationic polymers or antibodies; and permeabilizing agents such as EDTA, PMNP and CaCl2. The present review also covers the different laboratory animal models normally used to treat Gram-negative bacterial infections with antimicrobial PDT. PMID:23550545

Polarized light microscopy reveals physiological and drug-induced changes in surfactant membrane assembly in alveolar type II pneumocytes.

PubMed

Haller, Thomas; Cerrada, Alejandro; Pfaller, Kristian; Braubach, Peter; Felder, Edward

2018-05-01

In alveolar type II (AT II) cells, pulmonary surfactant (PS) is synthetized, stored and exocytosed from lamellar bodies (LBs), specialized large secretory organelles. By applying polarization microscopy (PM), we confirm a specific optical anisotropy of LBs, which indicates a liquid-crystalline mesophase of the stored surfactant phospholipids (PL) and an unusual case of a radiation-symmetric, spherocrystalline organelle. Evidence is shown that the degree of anisotropy is dependent on the amount of lipid layers and their degree of hydration, but unaffected by acutely modulating vital cell parameters like intravesicular pH or cellular energy supply. In contrast, physiological factors that perturb this structure include osmotic cell volume changes and LB exocytosis. In addition, we found two pharmaceuticals, Amiodarone and Ambroxol, both of which severely affect the liquid-crystalline order. Our study shows that PM is an easy, very sensitive, but foremost non-invasive and label-free method able to collect important structural information of PS assembly in live AT II cells which otherwise would be accessible by destructive or labor intense techniques only. This may open new approaches to dynamically investigate LB biosynthesis - the incorporation, folding and packing of lipid membranes - or the initiation of pathological states that manifest in altered LB structures. Due to the observed drug effects, we further suggest that PM provides an appropriate way to study unspecific drug interactions with alveolar cells and even drug-membrane interactions in general. Copyright © 2018 Elsevier B.V. All rights reserved.

Sequential steps of macroautophagy and chaperone-mediated autophagy are involved in the irreversible process of posterior silk gland histolysis during metamorphosis of Bombyx mori.

PubMed

Shiba, Hajime; Yabu, Takeshi; Sudayama, Makoto; Mano, Nobuhiro; Arai, Naoto; Nakanishi, Teruyuki; Hosono, Kuniaki

2016-04-15

To elucidate the degradation process of the posterior silk gland during metamorphosis of the silkworm ITALIC! Bombyx mori, tissues collected on the 6th day after entering the 5th instar (V6), prior to spinning (PS), during spinning (SP) and after cocoon formation (CO) were used to analyze macroautophagy, chaperone-mediated autophagy (CMA) and the adenosine triphosphate (ATP)-dependent ubiquitin proteasome. Immediately after entering metamorphosis stage PS, the levels of ATP and phosphorylated p70S6 kinase protein decreased spontaneously and continued to decline at SP, followed by a notable restoration at CO. In contrast, phosphorylated AMP-activated protein kinase α (AMPKα) showed increases at SP and CO. Most of the Atg8 protein was converted to form II at all stages. The levels of ubiquitinated proteins were high at SP and CO, and low at PS. The proteasome activity was high at V6 and PS but low at SP and CO. In the isolated lysosome fractions, levels of Hsc70/Hsp70 protein began to increase at PS and continued to rise at SP and CO. The lysosomal cathepsin B/L activity showed a dramatic increase at CO. Our results clearly demonstrate that macroautophagy occurs before entering the metamorphosis stage and strongly suggest that the CMA pathway may play an important role in the histolysis of the posterior silk gland during metamorphosis. © 2016. Published by The Company of Biologists Ltd.

Lignin-degrading Peroxidases from Genome of Selective Ligninolytic Fungus Ceriporiopsis subvermispora*

PubMed Central

Fernández-Fueyo, Elena; Ruiz-Dueñas, Francisco J.; Miki, Yuta; Martínez, María Jesús; Hammel, Kenneth E.; Martínez, Angel T.

2012-01-01

The white-rot fungus Ceriporiopsis subvermispora delignifies lignocellulose with high selectivity, but until now it has appeared to lack the specialized peroxidases, termed lignin peroxidases (LiPs) and versatile peroxidases (VPs), that are generally thought important for ligninolysis. We screened the recently sequenced C. subvermispora genome for genes that encode peroxidases with a potential ligninolytic role. A total of 26 peroxidase genes was apparent after a structural-functional classification based on homology modeling and a search for diagnostic catalytic amino acid residues. In addition to revealing the presence of nine heme-thiolate peroxidase superfamily members and the unexpected absence of the dye-decolorizing peroxidase superfamily, the search showed that the C. subvermispora genome encodes 16 class II enzymes in the plant-fungal-bacterial peroxidase superfamily, where LiPs and VPs are classified. The 16 encoded enzymes include 13 putative manganese peroxidases and one generic peroxidase but most notably two peroxidases containing the catalytic tryptophan characteristic of LiPs and VPs. We expressed these two enzymes in Escherichia coli and determined their substrate specificities on typical LiP/VP substrates, including nonphenolic lignin model monomers and dimers, as well as synthetic lignin. The results show that the two newly discovered C. subvermispora peroxidases are functionally competent LiPs and also suggest that they are phylogenetically and catalytically intermediate between classical LiPs and VPs. These results offer new insight into selective lignin degradation by C. subvermispora. PMID:22437835

Perinatal Choline Supplementation Reduces Amyloidosis and Increases Choline Acetyltransferase Expression in the Hippocampus of the APPswePS1dE9 Alzheimer's Disease Model Mice.

PubMed

Mellott, Tiffany J; Huleatt, Olivia M; Shade, Bethany N; Pender, Sarah M; Liu, Yi B; Slack, Barbara E; Blusztajn, Jan K

2017-01-01

Prevention of Alzheimer's disease (AD) is a major goal of biomedical sciences. In previous studies we showed that high intake of the essential nutrient, choline, during gestation prevented age-related memory decline in a rat model. In this study we investigated the effects of a similar treatment on AD-related phenotypes in a mouse model of AD. We crossed wild type (WT) female mice with hemizygous APPswe/PS1dE9 (APP.PS1) AD model male mice and maintained the pregnant and lactating dams on a control AIN76A diet containing 1.1 g/kg of choline or a choline-supplemented (5 g/kg) diet. After weaning all offspring consumed the control diet. As compared to APP.PS1 mice reared on the control diet, the hippocampus of the perinatally choline-supplemented APP.PS1 mice exhibited: 1) altered levels of amyloid precursor protein (APP) metabolites-specifically elevated amounts of β-C-terminal fragment (β-CTF) and reduced levels of solubilized amyloid Aβ40 and Aβ42 peptides; 2) reduced number and total area of amyloid plaques; 3) preserved levels of choline acetyltransferase protein (CHAT) and insulin-like growth factor II (IGF2) and 4) absence of astrogliosis. The data suggest that dietary supplementation of choline during fetal development and early postnatal life may constitute a preventive strategy for AD.

Perinatal Choline Supplementation Reduces Amyloidosis and Increases Choline Acetyltransferase Expression in the Hippocampus of the APPswePS1dE9 Alzheimer's Disease Model Mice

PubMed Central

Mellott, Tiffany J.; Huleatt, Olivia M.; Shade, Bethany N.; Pender, Sarah M.; Liu, Yi B.; Slack, Barbara E.; Blusztajn, Jan K.

2017-01-01

Prevention of Alzheimer's disease (AD) is a major goal of biomedical sciences. In previous studies we showed that high intake of the essential nutrient, choline, during gestation prevented age-related memory decline in a rat model. In this study we investigated the effects of a similar treatment on AD-related phenotypes in a mouse model of AD. We crossed wild type (WT) female mice with hemizygous APPswe/PS1dE9 (APP.PS1) AD model male mice and maintained the pregnant and lactating dams on a control AIN76A diet containing 1.1 g/kg of choline or a choline-supplemented (5 g/kg) diet. After weaning all offspring consumed the control diet. As compared to APP.PS1 mice reared on the control diet, the hippocampus of the perinatally choline-supplemented APP.PS1 mice exhibited: 1) altered levels of amyloid precursor protein (APP) metabolites–specifically elevated amounts of β-C-terminal fragment (β-CTF) and reduced levels of solubilized amyloid Aβ40 and Aβ42 peptides; 2) reduced number and total area of amyloid plaques; 3) preserved levels of choline acetyltransferase protein (CHAT) and insulin-like growth factor II (IGF2) and 4) absence of astrogliosis. The data suggest that dietary supplementation of choline during fetal development and early postnatal life may constitute a preventive strategy for AD. PMID:28103298

Clinical evaluation of plasma insulin and C-peptide levels with 3 different high-flux dialyzers in diabetic patients on hemodialysis.

PubMed

Abe, M; Okada, K; Maruyama, T; Inoshita, A; Ikeda, K; Uto, E; Kikuchi, F; Matsumoto, K

2008-10-01

Changes in plasma immunoreactive insulin (IRI) and connecting-peptide immunoreactivity (CPR) concentrations during hemodialysis (HD) were evaluated in diabetic HD patients with 3 different high-flux membranes. The removal properties of the membranes were compared. In this prospective controlled study, 15 stable diabetic patients on HD were randomly selected for 6 HD sessions with 3 different membranes: polysulfone (PS), cellulose triacetate (CTA), and polymethylmethacrylate (PMMA). Blood samples were obtained from the blood tubing at the arterial (A) site at the beginning and end of the sixth HD session. At 60 minutes after dialysis initiation, blood samples were obtained from both the A and venous (V) sites of the dialyzer to investigate the clearance and removal properties of the membranes. The plasma IRI and CPR levels decreased significantly at each time point with all 3 membranes. IRI clearance with the PS membrane was significantly higher than that with the CTA and PMMA membranes. No difference was observed in the IRI reduction rate between the 3 membranes. CPR clearance and reduction rate with the PMMA membrane were lower than with the PS and CTA membranes. No significant difference was observed in serum creatinine clearance and reduction rates between the 3 membranes; however, serum urea nitrogen clearance was significantly lower with the PMMA membrane compared with the PS and CTA membranes. A significantly high beta2-microglobulin clearance and reduction rate was achieved in the order PS > CTA > PMMA. Plasma IRI and CPR are cleared by HD; their clearance rates differ with the dialyzer membranes. Plasma IRI clearance with the PS membrane is higher than that with the CTA and PMMA membranes.

Role of Wnt4/β-catenin, Ang II/TGFβ, ACE2, NF-κB, and IL-18 in attenuating renal ischemia/reperfusion-induced injury in rats treated with Vit D and pioglitazone.

PubMed

Ali, Rabab M; Al-Shorbagy, Muhammad Y; Helmy, Maged W; El-Abhar, Hanan S

2018-07-15

Renal ischemia-reperfusion injury (I/RI) remains a critical clinical situation. Several evidence revealed the potential reno-protective effects of Vitamin D and/or pioglitazone, on renal I/RI. This study addresses the possible involvement of the Wnt4/β-catenin signaling, p-S536NF-κBp65, PPARγ, Ang II/TGF-β, and ACE2 as potential effectors to vitamin D and pioglitazone-mediated renoprotective effects. Two sets of Sprague-Dawley rats (n = 30 rat each), were randomized into sham, I/R, Vit D "alfacalcidol" (5 ng/kg/day), pioglitazone (5 mg/kg/day), and Vit D + pioglitazone groups. In all groups renal biochemical parameters, as well as inflammatory and structural profiles were assessed, besides the expression/contents of Wnt4/β-catenin and pS536-NF-κBp65. All treatments started 7 days before I/RI and animals were killed 24 h after I/RI in the first set, while those in the 2nd set continued their treatments for 14 days. After 24 h, all pre-treatments impeded theI/R effect on neutrophils recruitment, p-S536NF-κBp65, IL-18, NGAL, caspase-3, AngII, ACE-2, PPARγ and TGF-β, besides the expression of Wnt4 and ACE-2 with notable reflection on histological changes. Two weeks after I/RI, except a marked up regulation in Wnt4 expression and a striking elevation in the β-catenin content, the magnitude of the injurious events was relatively less pronounced, an effect that was mostly augmented by the different treatments. The current study pledges a promising and novel reno-protective role of the administration of Vit D and pioglitazone entailing a potential involvement of ICAM-1, MPO, NF-κB, Ang II, ACE2, TGFβ, and a modulation of Wnt4/β-catenin pathway. Copyright © 2018 Elsevier B.V. All rights reserved.

Potential Pitfalls of Reporting and Bias in Observational Studies With Propensity Score Analysis Assessing a Surgical Procedure: A Methodological Systematic Review.

PubMed

Lonjon, Guillaume; Porcher, Raphael; Ergina, Patrick; Fouet, Mathilde; Boutron, Isabelle

2017-05-01

To describe the evolution of the use and reporting of propensity score (PS) analysis in observational studies assessing a surgical procedure. Assessing surgery in randomized controlled trials raises several challenges. Observational studies with PS analysis are a robust alternative for comparative effectiveness research. In this methodological systematic review, we identified all PubMed reports of observational studies with PS analysis that evaluated a surgical procedure and described the evolution of their use over time. Then, we selected a sample of articles published from August 2013 to July 2014 and systematically appraised the quality of reporting and potential bias of the PS analysis used. We selected 652 reports of observational studies with PS analysis. The publications increased over time, from 1 report in 1987 to 198 in 2013. Among the 129 reports assessed, 20% (n = 24) did not detail the covariates included in the PS and 77% (n = 100) did not report a justification for including these covariates in the PS. The rate of missing data for potential covariates was reported in 9% of articles. When a crossover by conversion was possible, only 14% of reports (n = 12) mentioned this issue. For matched analysis, 10% of articles reported all 4 key elements that allow for reproducibility of a PS-matched analysis (matching ratio, method to choose the nearest neighbors, replacement and method for statistical analysis). Observational studies with PS analysis in surgery are increasing in frequency, but specific methodological issues and weaknesses in reporting exist.

Identification of AUXIN RESPONSE FACTOR gene family from Prunus sibirica and its expression analysis during mesocarp and kernel development.

PubMed

Niu, Jun; Bi, Quanxin; Deng, Shuya; Chen, Huiping; Yu, Haiyan; Wang, Libing; Lin, Shanzhi

2018-01-24

Auxin response factors (ARFs) in auxin signaling pathway are an important component that can regulate the transcription of auxin-responsive genes involved in almost all aspects of plant growth and development. To our knowledge, the comprehensive and systematic characterization of ARF genes has never been reported in Prunus sibirica, a novel woody biodiesel feedstock in China. In this study, we identified 14 PsARF genes with a perfect open reading frame (ORF) in P. sibirica by using its previous transcriptomic data. Conserved motif analysis showed that all identified PsARF proteins had typical DNA-binding and ARF domain, but 5 members (PsARF3, 8 10, 16 and 17) lacked the dimerization domain. Phylogenetic analysis of the ARF proteins generated from various plant species indicated that ARFs could be categorized into 4 major groups (Class I, II, III and IV), in which all identified ARFs from P. sibirica showed a closest relationship with those from P. mume. Comparison of the expression profiles of 14 PsARF genes in different developmental stages of Siberian apricot mesocarp (SAM) and kernel (SAK) reflected distinct temporal or spatial expression patterns for PsARF genes. Additionally, based on the expressed data from fruit and seed development of multiple plant species, we identified 1514 ARF-correlated genes using weighted gene co-expression network analysis (WGCNA). And the major portion of ARF-correlated gene was characterized to be involved in protein, nucleic acid and carbohydrate metabolic, transport and regulatory processes. In summary, we systematically and comprehensively analyzed the structure, expression pattern and co-expression network of ARF gene family in P. sibirica. All our findings provide theoretical foundation for the PsARF gene family and will pave the way for elucidating the precise role of PsARF genes in SAM and SAK development.

Different intraoperative kinematics with comparable clinical outcomes of ultracongruent and posterior stabilized mobile-bearing total knee arthroplasty.

PubMed

Kim, Tae Woo; Lee, Sang Min; Seong, Sang Cheol; Lee, Sahnghoon; Jang, Jak; Lee, Myung Chul

2016-09-01

There remains no consensus as to whether mobile total knee arthroplasty (TKA) should use a posterior cruciate ligament-sacrificing ultracongruent (UC) or a posterior cruciate ligament-substituting posterior stabilized (PS) prosthesis. The purpose of this study was to assess intraoperative kinematics and clinical outcomes of UC and PS rotating platform mobile-bearing TKA. In this randomized controlled study, mobile UC TKA prostheses (n = 45) were compared with mobile PS TKA prostheses (n = 45) with regard to intraoperative kinematics and clinical outcomes. The passive kinematic study using intraoperative navigation system included anterior/posterior translation, varus/valgus alignment and rotation of femur during flexion. The patients were clinically and radiographically evaluated over a 3-year follow-up. Paradoxical anterior translation of the femur was 10.8 ± 5.2 mm in the UC knee from 0° to 82° of knee flexion and 8.7 ± 3.0 mm in the PS knee from 0° to 70° of knee flexion (p = 0.027). Paradoxical internal rotation of the femur was 5.8° in the UC knees and 9.9° in the PS knees (p = 0.003). But, there was no significant difference between the groups in regard to the coronal alignment. There was no significant difference in the range of motion, KS knee scores, KS function scores, and WOMAC index scores. Despite different intraoperative kinematics between mobile UC and mobile PS TKA, neither design reproduced physiologic knee kinematics and there was no difference in clinical outcomes between the two groups. The clinical relevance of the study is that despite different intraoperative kinematics, UC design can be a considerable alternative to PS design in mobile-bearing TKA in respect of clinical outcomes. II.

Usefulness of rCBF analysis in diagnosing Parkinson's disease: supplemental role with MIBG myocardial scintigraphy.

PubMed

Nagamachi, Shigeki; Wakamatsu, Hideyuki; Kiyohara, Shogo; Fujita, Seigo; Futami, Shigemi; Tamura, Shozo; Nakazato, Masamitsu; Yamashita, Syuichi; Arita, Hideo; Nishii, Ryuichi; Kawai, Keiichi

2008-08-01

(123)I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy is a useful tool for differentiating idiopathic Parkinson's disease (PD) from parkinsonism (PS) caused by other disorders. However, cardiac MIBG uptake is affected by various causes. Alternatively, hypoperfusion in the occipital lobe of PD is reported recently. The objective is to clarify the correlation between regional cerebral blood flow (rCBF) alteration and cardiac MIBG uptake in PD. In addition, we examined whether additional brain perfusion analysis improved the differential diagnostic ability for PD from PS when compared with MIBG scintigraphy alone. Forty-nine patients with PD (27 mild groups: Hoehn and Yahr stages I, II; 22 severe groups: Hoehn and Yahr stages III, IV) and 28 patients with PS participated. We compared absolute rCBF values between PD and PS. In addition, we determined correlation between MIBG parameters and each rCBF value. Finally, we compared the diagnostic ability for the differentiation of PD from PS between two diagnostic criteria, each MIBG index abnormality alone [heart-to-mediastinum ratio, H/M (E) < 1.9, H/E (D) < 1.7, washout rate > 40%] and each MIBG index abnormality or occipital lobe hypoperfusion (<36 ml/100 g per min). Absolute rCBF value of occipital lobe was significantly lower in severe PD as compared with PS or mild PD. In the correlation analysis, rCBF of occipital lobe correlated positively with MIBG parameters (H/M). Regarding the diagnostic ability, sensitivity improved by accounting for occipital hypoperfusion as compared with MIBG indices alone. In contrast, neither specificity nor accuracy improved by adding occipital lobe analysis. MIBG parameters (H/M) correlated positively with occipital hypoperfusion in PD. In the differential diagnosis between PD and PS, although its usefulness might be limited, analysis of rCBF in the occipital lobe added to (123)I-MIBG myocardial imaging can be recommended.

Losses and depolarization of ultracold neutrons on neutron guide and storage materials

NASA Astrophysics Data System (ADS)

Bondar, V.; Chesnevskaya, S.; Daum, M.; Franke, B.; Geltenbort, P.; Göltl, L.; Gutsmiedl, E.; Karch, J.; Kasprzak, M.; Kessler, G.; Kirch, K.; Koch, H.-C.; Kraft, A.; Lauer, T.; Lauss, B.; Pierre, E.; Pignol, G.; Reggiani, D.; Schmidt-Wellenburg, P.; Sobolev, Yu.; Zechlau, T.; Zsigmond, G.

2017-09-01

At Institut Laue-Langevin (ILL) and Paul Scherrer Institute (PSI), we have measured the losses and depolarization probabilities of ultracold neutrons on various materials: (i) nickel-molybdenum alloys with weight percentages of 82/18, 85/15, 88/12, 91/9, and 94/6 and natural nickel Ni100, (ii) nickel-vanadium NiV93/7, (iii) copper, and (iv) deuterated polystyrene (dPS). For the different samples, storage-time constants up to ˜460 s were obtained at room temperature. The corresponding loss parameters for ultracold neutrons, η , varied between 1.0 ×10-4 and 2.2 ×10-4 . All η values are in agreement with theory except for dPS, where anomalous losses at room temperature were established with four standard deviations. The depolarization probabilities per wall collision β measured with unprecedented sensitivity varied between 0.7 ×10-6 and 9.0 ×10-6 . Our depolarization result for copper differs from other experiments by 4.4 and 15.8 standard deviations. The β values of the paramagnetic NiMo alloys over molybdenum content show an increase of β with increasing Mo content. This is in disagreement with expectations from literature. Finally, ferromagnetic behavior of NiMo alloys at room temperature was found for molybdenum contents of 6.5 at.% or less and paramagnetic behavior for more than 8.7 at.%. This may contribute to solving an ambiguity in literature.

Root exudation of phytosiderophores from soil-grown wheat

PubMed Central

Oburger, Eva; Gruber, Barbara; Schindlegger, Yvonne; Schenkeveld, Walter D C; Hann, Stephan; Kraemer, Stephan M; Wenzel, Walter W; Puschenreiter, Markus

2014-01-01

For the first time, phytosiderophore (PS) release of wheat (Triticum aestivum cv Tamaro) grown on a calcareous soil was repeatedly and nondestructively sampled using rhizoboxes combined with a recently developed root exudate collecting tool. As in nutrient solution culture, we observed a distinct diurnal release rhythm; however, the measured PS efflux was c. 50 times lower than PS exudation from the same cultivar grown in zero iron (Fe)-hydroponic culture. Phytosiderophore rhizosphere soil solution concentrations and PS release of the Tamaro cultivar were soil-dependent, suggesting complex interactions of soil characteristics (salinity, trace metal availability) and the physiological status of the plant and the related regulation (amount and timing) of PS release. Our results demonstrate that carbon and energy investment into Fe acquisition under natural growth conditions is significantly smaller than previously derived from zero Fe-hydroponic studies. Based on experimental data, we calculated that during the investigated period (21–47 d after germination), PS release initially exceeded Fe plant uptake 10-fold, but significantly declined after c. 5 wk after germination. Phytosiderophore exudation observed under natural growth conditions is a prerequisite for a more accurate and realistic assessment of Fe mobilization processes in the rhizosphere using both experimental and modeling approaches. PMID:24890330

Trehalose protects Mn-depleted photosystem 2 preparations against the donor-side photoinhibition.

PubMed

Yanykin, D V; Khorobrykh, A A; Mamedov, M D; Klimov, V V

2016-11-01

Recently, it has been shown that the addition of 1M trehalose leads to the increase of the rate of oxygen photoconsumption associated with activation of electron transport in the reaction center of photosystem 2 (PS2) in Mn-depleted PS2 membranes (apo-WOC-PS2) [37]. In the present work the effect of trehalose on photoinhibition of apo-WOC-PS2 preparations (which are characterized by a high sensitivity to the donor side photoinhibition of PS2) was investigated. The degree of photoinhibition was estimated by the loss of the capability of exogenous electron donor (sodium ascorbate) to reactivate the electron transport (measured by light-induced changes of chlorophyll fluorescence yield (∆F)) in apo-WOC-PS2. It was found that 1M trehalose enhanced the Mn 2+ -dependent suppression of photoinhibition of apo-WOC-PS2: in the presence of trehalose the addition of 0.2μM Mn 2+ (corresponding to 2 Mn 2+ per one reaction center) was sufficient for an almost complete suppression of the donor side photoinhibition of the complex. In the absence of trehalose it was necessary to add 100μM Mn 2+ to achieve a similar result. The effect of trehalose was observed during photoinhibition of apo-WOC-PS2 at low (15μmolphotons -1 m -2 ) and high (200μmolphotons -1 m -2 ) light intensity. When Mn 2+ was replaced by other PS2 electron donors (ferrocyanide, DPC) as well as by Ca 2+ the protective effect of trehalose was not observed. It was also found that 1M trehalose decreased photoinhibition of apo-WOC-PS2 if the samples contained endogenous manganese (1-2 Mn ions per one RC was enough for the maximum protection effect). It is concluded that structural changes in PS2 caused by the addition of trehalose enhance the capability of photochemical reaction centers of apo-WOC-PS2 to accept electrons from manganese (both exogenous and endogenous), which in turn leads to a considerable suppression of the donor side photoinhibition of PS2. Copyright © 2016 Elsevier B.V. All rights reserved.

Tunneling transport of mono- and few-layers magnetic van der Waals MnPS3

NASA Astrophysics Data System (ADS)

Lee, Sungmin; Choi, Ki-Young; Lee, Sangik; Park, Bae Ho; Park, Je-Geun; Emergent Phenomena Group Team; Department of Physics, Konkuk University Collaboration

We have investigated the tunneling transport of mono- and few-layers of MnPS3 by using conductive atomic force microscopy. Due to the band alignment of indium tin oxide/MnPS3/Pt-Ir tip junction, the key features of both Schottky junction and Fowler-Nordheim tunneling (FNT) were observed for all the samples with varying thickness. Using the FNT model and assuming the effective electron mass (0.5 me) of MnPS3, we estimate the tunneling barrier height to be 1.31 eV and the dielectric breakdown strength as 5.41 MV/cm. The work at the IBS CCES was supported by the research program of Institute for Basic Science. S.L. and B.H.P were supported by the National Research Foundation of Korea (NRF) Grants funded by the Korea government (MSIP).

Phenol abatement using persulfate activated by nZVI, H2O2 and NaOH and development of a kinetic model for alkaline activation.

PubMed

Lominchar, Miguel A; Rodríguez, Sergio; Lorenzo, David; Santos, Noelia; Romero, Arturo; Santos, Aurora

2018-01-01

Three persulfate (PS) activation methods (nanoparticles of zero-valent iron (nZVI), hydrogen peroxide and alkali) were compared using phenol as target pollutant. Firstly, four experiments were conducted at 25°C in a batch way using the same initial phenol and oxidant concentrations (10 mM and 420 mM, respectively), being the molar ratio activator/PS fixed to 0.005 with nZVI (mass ratio 0.0011 nZVI/PS), to 2 using hydrogen peroxide and to 2 and 4 with NaOH. Phenol and PS conversions and aromatic byproducts profiles during 168 h reaction time were measured and compared, as well as mineralization and ecotoxicity of the samples. It was found that both phenol and aromatic byproducts (catechol and hydroquinone) totally disappeared using PS activated by alkali before 24 h, while a significant amount of aromatic intermediates was obtained with nZVI and H 2 O 2 . Additional runs were carried out using shorter times (0-2 h) to discriminate the oxidation route and the kinetic model of phenol abatement by using PS activated by alkali. Different initial concentrations of phenol (5-15 mM), PS (210 and 420 mM) and molar ratio NaOH/PS (2 and 4) were employed. The kinetic model obtained predicts accurately the evolution of phenol, persulfate, hydroquinone and catechol.

Response of mitochondrial thioredoxin PsTrxo1, antioxidant enzymes, and respiration to salinity in pea (Pisum sativum L.) leaves.

PubMed

Martí, María C; Florez-Sarasa, Igor; Camejo, Daymi; Ribas-Carbó, Miquel; Lázaro, Juan J; Sevilla, Francisca; Jiménez, Ana

2011-07-01

Mitochondria play an essential role in reactive oxygen species (ROS) signal transduction in plants. Redox regulation is an essential feature of mitochondrial function, with thioredoxin (Trx), involved in disulphide/dithiol interchange, playing a prominent role. To explore the participation of mitochondrial PsTrxo1, Mn-superoxide dismutase (Mn-SOD), peroxiredoxin (PsPrxII F), and alternative oxidase (AOX) under salt stress, their transcriptional and protein levels were analysed in pea plants growing under 150 mM NaCl for a short and a long period. The activities of mitochondrial Mn-SOD and Trx together with the in vivo activities of the alternative pathway (AP) and the cytochrome pathway (CP) were also determined, combined with the characterization of the plant physiological status as well as the mitochondrial oxidative indicators. The analysis of protein and mRNA levels and activities revealed the importance of the post-transcriptional and post-translational regulation of these proteins in the response to salt stress. Increases in AOX protein amount correlated with increases in AP capacity, whereas in vivo AP activity was maintained under salt stress. Similarly, Mn-SOD activity was also maintained. Under all the stress treatments, photosynthesis, stomatal conductance, and CP activity were decreased although the oxidative stress in leaves was only moderate. However, an increase in lipid peroxidation and protein oxidation was found in mitochondria isolated from leaves under the short-term salinity conditions. In addition, an increase in mitochondrial Trx activity was produced in response to the long-term NaCl treatment. The results support a role for PsTrxo1 as a component of the defence system induced by NaCl in pea mitochondria, providing the cell with a mechanism by which it can respond to changing environment protecting mitochondria from oxidative stress together with Mn-SOD, AOX, and PrxII F.

Detection of severe digital vasculopathy in systemic sclerosis by colour Doppler sonography is associated with digital ulcers.

PubMed

Lüders, Susanne; Friedrich, Stefanie; Ohrndorf, Sarah; Glimm, Anne-Marie; Burmester, Gerd-Rüdiger; Riemekasten, Gabriela; Backhaus, Marina

2017-11-01

Colour Doppler ultrasonography (CDUS) is very important in general vascular diagnostic procedures. Its role in determining the extent of vasculopathy in Systemic Sclerosis (SSc) needs further investigation. The aim of this study was to compare the presence of altered arteries with nailfold capillaroscopy and clinical signs of ischaemia, that is, digital ulcers or pitting scars (DU/PS). A feasible CDUS protocol is provided. Two thousand five hundred and twenty-eight arteries of the fingers, palms and wrists from 79 SSc patients (32 arteries per patient) were examined using CDUS. Furthermore, nailfold capillaroscopy, clinical and laboratory data were evaluated. Narrowed or occluded lumens were seen in 39.8% of all assessable arteries (n = 2489) and 48.9% of all proper palmar digital arteries (n = 1564) but only 15.6% (P < 0.0001) of proximal arteries (n = 924). Fingerwise analyses presented significant coincidence of pathological CDUS findings and DU/PS (P = 0.0009). Pathological CDUS findings were also associated with elevated CRP concentrations, current or past smoking with ⩾20 pack-years, male gender and present or past DU/PS. Receiver operating characteristic curve analysis (area under the curve = 0.727) suggested a cut-off value of ⩾20% pathological vessels (sensitivity: 90.7%; specificity: 47.8%) for the presence of DU/PS. An examination protocol focusing on the right-hand digits II-V (proper palmar digital arteries) revealed similar results (area under the curve = 0.751; sensitivity: 93.0%; specificity: 43.5%). CDUS of hand and finger arteries allows measurement of the extent of SSc vasculopathy, which is associated with clinical signs of chronic malperfusion. A shortened examination protocol of CDUS (right-hand digits II-V; 15 min instead of 45 min examination time) could complement vascular diagnostics in SSc. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Regulation of CDP-diacylglycerol synthesis and utilization by inositol and choline in Schizosaccharomyces pombe.

PubMed Central

Gaynor, P M; Greenberg, M L

1992-01-01

CDP-diacylglycerol (CDP-DG) is an important branchpoint intermediate in eucaryotic phospholipid biosynthesis and could be a key regulatory site in phospholipid metabolism. Therefore, we examined the effects of growth phase, phospholipid precursors, and the disruption of phosphatidylcholine (PC) synthesis on the membrane-associated phospholipid biosynthetic enzymes CDP-DG synthase, phosphatidylglycerolphosphate (PGP) synthase, phosphatidylinositol (PI) synthase, and phosphatidylserine (PS) synthase in cell extracts of the fission yeast Schizosaccharomyces pombe. In complete synthetic medium containing inositol, maximal expression of CDP-DG synthase, PGP synthase, PI synthase, and PS synthase in wild-type cells occurred in the exponential phase of growth and decreased two- to fourfold in the stationary phase of growth. In cells starved for inositol, this decrease in PGP synthase, PI synthase, and PS synthase expression was not observed. Starvation for inositol resulted in a twofold derepression of PGP synthase and PS synthase expression, while PI synthase expression decreased initially and then remained constant. Upon the addition of inositol to inositol-starved cells, there was a rapid and continued increase in PI synthase expression. We examined expression of these enzymes in cho2 and cho1 mutants, which are blocked in the methylation pathway for synthesis of PC. Choline starvation resulted in a decrease in PS synthase and CDP-DG synthase expression in cho1 but not cho2 cells. Expression of PGP synthase and PI synthase was not affected by choline starvation. Inositol starvation resulted in a 1.7-fold derepression of PGP synthase expression in cho2 but not cho1 cells when PC was synthesized. PS synthase expression was not depressed, while CDP-DG synthase and PI synthase expression decreased in cho2 and cho1 cells in the absence of inositol. These results demonstrate that (i) CDP-DG synthase, PGP synthase, PI synthase, and PS synthase are similarly regulated by growth phase; (ii) inositol affects the expression of PGP synthase, PI synthase, and PS synthase; (iii) disruption of the methylation pathway results in aberrant patterns of regulation of growth phase and phospholipid precursors. Important differences between S. pombe and Saccharomyces cerevisiae with regard to regulation of these enzymes are discussed. PMID:1324908

7 CFR 1753.38 - Procurement procedures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... specifications and equipment requirements (required only for projects expected to exceed $500,000 or 25% of the... technology. (ii) The borrower shall review in detail all exceptions to the P&S. No exceptions will be... only for projects that are expected to exceed $500,000 or 25% of the loan, whichever is less), sealed...

7 CFR 1753.38 - Procurement procedures.

Code of Federal Regulations, 2014 CFR

2014-01-01

... specifications and equipment requirements (required only for projects expected to exceed $500,000 or 25% of the... technology. (ii) The borrower shall review in detail all exceptions to the P&S. No exceptions will be... only for projects that are expected to exceed $500,000 or 25% of the loan, whichever is less), sealed...

7 CFR 1753.38 - Procurement procedures.

Code of Federal Regulations, 2012 CFR

2012-01-01

... specifications and equipment requirements (required only for projects expected to exceed $500,000 or 25% of the... technology. (ii) The borrower shall review in detail all exceptions to the P&S. No exceptions will be... only for projects that are expected to exceed $500,000 or 25% of the loan, whichever is less), sealed...

7 CFR 1753.38 - Procurement procedures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... specifications and equipment requirements (required only for projects expected to exceed $500,000 or 25% of the... technology. (ii) The borrower shall review in detail all exceptions to the P&S. No exceptions will be... only for projects that are expected to exceed $500,000 or 25% of the loan, whichever is less), sealed...

Time-resolved optical emission spectroscopic studies of picosecond laser produced Cr plasma

NASA Astrophysics Data System (ADS)

Rao, Kavya H.; Smijesh, N.; Klemke, N.; Philip, R.; Litvinyuk, I. V.; Sang, R. T.

2018-06-01

Time-resolved optical emission spectroscopic measurements of a plasma generated by irradiating a Cr target using 60 picosecond (ps) and 300 ps laser pulses are carried out to investigate the variation in the line width (δλ) of emission from neutrals and ions for increasing ambient pressures. Measurements ranging from 10-6 Torr to 102 Torr show a distinctly different variation in the δλ of neutrals (Cr I) compared to that of singly ionized Cr (Cr II), for both irradiations. δλ increases monotonously with pressure for Cr II, but an oscillation is evident at intermediate pressures for Cr I. This oscillation does not depend on the laser pulse widths used. In spite of the differences in the plasma formation mechanisms, it is experimentally found that there is an optimum intermediate background pressure for which δλ of neutrals drops to a minimum. Importantly, these results underline the fact that for intermediate pressures, the usual practice of calculating the plasma number density from the δλ of neutrals needs to be judiciously done, to avoid reaching inaccurate conclusions.

Imaging the Molecular Signatures of Apoptosis and Injury with Radiolabeled Annexin V

PubMed Central

Blankenberg, Francis G.

2009-01-01

Annexin V is a ubiquitous intracellular protein in humans that has a variety of intriguing characteristics, including a nanomolar affinity for the membrane-bound constitutive anionic phospholipid known as phosphatidylserine (PS). PS is selectively expressed on the surface of apoptotic or physiologically stressed cells. As such, radiolabeled forms of annexin V have been used in both animal models and human Phase I and Phase II trials to determine if this tracer can be employed as an early surrogate marker of therapeutic efficacy in NSCLC and non-Hodgkin's lymphoma. Many other pulmonary imaging applications of radiolabeled annexin V are also possible, including the detection and monitoring of active pulmonary inflammation and other pathophysiologic stressors in a variety of diseases. In this article, the salient molecular features of apoptosis (and other forms of cell death) that permits imaging with radiolabeled annexin V will be discussed. The latest results from Phase II imaging trials with NSCLC and non-Hodgkin's lymphoma will be also be detailed. Finally, the potential future application of this tracer for the imaging of other pulmonary pathologies will be outlined. PMID:19687221

Artificial Photosystem I and II: Highly Selective solar fuels and tandem photocatalysis

NASA Astrophysics Data System (ADS)

Ding, Yuchen; Castellanos, Ignacio; Cerkovnik, Logan; Nagpal, Prashant

2014-03-01

Artificial photosynthesis, or generation of solar fuels from CO2/H2O, can provide an important alternative for rising CO2 emission and renewable energy generation. In our recent work, composite photocatalysts (CPCs) made from widebandgap nanotubes and different QDs were used to mimic Photosystem II (PS680) and I (PS700), respectively. By tuning the redox potentials using the size, composition and energy band alignment of QDs, we demonstrate highly selective (>90%) and efficient production of ethane, ethanol and acetaldehyde as solar fuels with different wavelengths of light. We also show that this selectivity is a result of precise energy band alignments (using cationic/anionic doping of nanotubes, QD size etc.), confirmed using measurements of electronic density of states, and alignment of higher redox potentials with hot-carriers can also lead to hot-carrier photocatalysis. This wavelength-selective CPCs can have important implications for inexpensive production of solar fuels including alkanes, alcohols, aldehydes and hydrogen, and making tandem structures (red, green, blue) with three CPCs, allowing almost full visible spectrum (410 ~ 730nm) utilization with different fuels produced simultaneously.

Health inequities: lower socio-economic conditions and higher incidences of intestinal parasites

PubMed Central

Östan, İpek; Kilimcioğlu, Ali A; Girginkardeşler, Nogay; Özyurt, Beyhan C; Limoncu, M Emin; Ok, Ülgen Z

2007-01-01

Background Intestinal parasitic infections affect child health and development and slow down growth, while reducing adults' productivity and work capacity. The aim of the present study was to determine and compare the incidences of intestinal parasitic infections and the socio-economic status of two near primary school children in Manisa, a western city of Turkey. Methods A total of 352 children were involved a questionnaire study from a private school (Ülkem Primary School – ÜPS, 116 children) and a community-based school (Şehzadeler Primary School – ŞPS, 236 children). Of these, stool samples could be obtained from a total of 294 students; 97 (83.6%) from ÜPS, and 197 (83.5%) from ŞPS. The wet mount preparations of the stool samples were examined; samples were also fixed in polyvinyl alcohol and examined with modified formalin ethyl acetate sedimentation and trichrome staining techniques. Data were analyzed using SPSS for Windows version 10.0. The chi-squared test was used for the analytic assessment. Results The percentages of the students found to be infected with intestinal parasites, were 78 (39.6%) and 13 (13.4%) in ŞPS and ÜPS, respectively. Totally 91 (31.0%) of the students from both schools were found to be infected with at least one intestinal parasite. Giardia lamblia was found to be the most common pathogenic intestinal parasite and Blastocystis hominis was prevalent independently from the hygienic conditions. The factors which significantly (p < 0.05) increase the incidence of intestinal parasites were uneducated and unemployed mother, lower social status of father, living in crowded houses with insufficient indoor spaces, using the tap water as drinking water, and living at shanty areas. Conclusion Intestinal parasitic infections in school children were found to be a public health problem that increased due to lower socio-economic conditions. We conclude that organization of education seminars including the topics such as prevention of the infectious diseases, improving general hygienic conditions, and application of supportive programs for the parents may be suggested not only to reduce intestinal parasitic infections, but also to elevate the socio-cultural levels. PMID:18042287

Damage creation in porous silicon irradiated by swift heavy ions

NASA Astrophysics Data System (ADS)

Canut, B.; Massoud, M.; Newby, P.; Lysenko, V.; Frechette, L.; Bluet, J. M.; Monnet, I.

2014-05-01

Mesoporous silicon (PS) samples were processed by anodising p+ Si wafers in (1:1) HF-ethanol solution. Different current densities were used to obtain three different porosities (41%, 56% and 75%). In all cases the morphology of the PS layer is columnar with a mean crystallite size between 12 nm (75% porosity) and 19 nm (41% porosity). These targets were irradiated at the GANIL accelerator, using different projectiles (130Xe ions of 91 MeV and 29 MeV, 238U ions of 110 MeV and 850 MeV) in order to vary the incident electronic stopping power Se. The fluences ranged between 1011 and 7 × 1013 cm-2. Raman spectroscopy and cross sectional SEM observations evidenced damage creation in the irradiated nanocrystallites, without any degradation of the PS layer morphology at fluences below 3 × 1012 cm-2. For higher doses, the columnar morphology transforms into a spongy-like structure. The damage cross sections, extracted from Raman results, increase with the electronic stopping power and with the sample porosity. At the highest Se (>10 keV nm-1) and the highest porosity (75%), the track diameter coincides with the crystallite diameter, indicating that a single projectile impact induces the crystallite amorphization along the major part of the ion path. These results were interpreted in the framework of the thermal spike model, taking into account the low thermal conductivity of the PS samples in comparison with that of bulk silicon.

Development of coatings for automated 96-blade solid phase microextraction-liquid chromatography-tandem mass spectrometry system, capable of extracting a wide polarity range of analytes from biological fluids.

PubMed

Mirnaghi, Fatemeh S; Pawliszyn, Janusz

2012-10-26

This work presents the development and evaluation of biocompatible polyacrylonitrile-polystyrene-divinylbenzene (PAN-PS-DVB) and polyacrylonitrile-phenylboronic acid (PAN-PBA) coatings for automated 96-blades (thin-film) solid phase microextraction (SPME) system, using high performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (MS/MS). The SPME condition was optimized for 60 min equilibrium extraction and 40 min desorption for PAN-PS-DVB, and 120 min equilibrium extraction and 60 min desorption for PAN-PBA for parallel sample preparation of up to 96 samples. The thin film geometry of the SPME blades provided good extraction efficiency due to the larger surface area of the coating, and simultaneous sample preparation provided fast and accurate analysis. The PAN-PS-DVB and PAN-PBA 96-blade SPME coatings were evaluated for extraction of analytes in a wide range of polarity (log P=2.8 to -3.7), and they demonstrated efficient extraction recovery (3.5-98.9% for PAN-PS-DVB and 4.0-74.1% for PAN-PBA) for both polar and non-polar groups of compounds. Reusability, reproducibility, and reliability of the system were evaluated. The results demonstrated that both coatings presented chemical and mechanical stability and long-lasting extraction efficiency for more than 100 usages in phosphate-buffered saline (PBS) and human plasma. Copyright © 2012 Elsevier B.V. All rights reserved.

Novel Insights in the Regulation of Phosphatidylserine Exposure in Human Red Blood Cells.

PubMed

Wesseling, Mauro C; Wagner-Britz, Lisa; Nguyen, Duc Bach; Asanidze, Salome; Mutua, Judy; Mohamed, Nagla; Hanf, Benjamin; Ghashghaeinia, Mehrdad; Kaestner, Lars; Bernhardt, Ingolf

2016-01-01

In previous publications we were able to demonstrate the exposure of phosphatidylserine (PS) in the outer membrane leaflet after activation of red blood cells (RBCs) by lysophosphatidic acid (LPA), phorbol-12 myristate-13acetate (PMA), or 4-bromo-A23187 (A23187). It has been concluded that three different mechanisms are responsible for the PS exposure in human RBCs: (i) Ca2+-stimulated scramblase activation (and flippase inhibition) by A23187, LPA, and PMA; (ii) PKCα activation by LPA and PMA; and (iii) enhanced lipid flip flop caused by LPA. Further studies aimed to elucidate interconnections between the increased Ca2+ content, scramblase- and PKCα-activation. In addition, the role of the Ca2+-activated K+ channel (Gardos channel) activity in the process of PS exposure needs to be investigated. The intracellular Ca2+ content and the PS exposure of RBCs have been investigated after treatment with LPA (2.5 µM), PMA (6 µM), or A23187 (2 µM). Fluo-4 and annexin V-FITC has been used to detect intracellular Ca2+ content and PS exposure, respectively. Both parameters (Ca2+ content, PS exposure) were studied using flow cytometry. Inhibitors of the scramblase, the PKCα, and the Gardos channel have been applied. The percentage of RBCs showing PS exposure after activation with LPA, PMA, or A23187 is significantly reduced after inhibition of the scramblase using the specific inhibitor R5421 as well as after the inhibition of the PKCα using chelerythrine chloride or calphostin C. The inhibitory effect is more pronounced when the scramblase and the PKCα are inhibited simultaneously. Additionally, the inhibition of the Gardos channel using charybdotoxin resulted in a significant reduction of the percentage of RBCs showing PS exposure under all conditions measured. Similar results were obtained when the Gardos channel activity was suppressed by increased extracellular K+ content. PS exposure is mediated by the Ca2+-dependent scramblase but also by PKCα activated by LPA and PMA in a Ca2+-dependent and a Ca2+-independent manner. Furthermore, we hypothesize that a hyperpolarisation of RBCs caused by the opening of the Gardos channel is essential for the scramblase activity as well as for a fraction of the LPA-induced Ca2+ entry. © 2016 The Author(s) Published by S. Karger AG, Basel.

Optical signal monitoring in phase modulated optical fiber transmission systems

NASA Astrophysics Data System (ADS)

Zhao, Jian

Optical performance monitoring (OPM) is one of the essential functions for future high speed optical networks. Among the parameters to be monitored, chromatic dispersion (CD) is especially important since it has a significant impact on overall system performance. In this thesis effective CD monitoring approaches for phase-shift keying (PSK) based optical transmission systems are investigated. A number of monitoring schemes based on radio frequency (RF) spectrum analysis and delay-tap sampling are proposed and their performance evaluated. A method for dispersion monitoring of differential phase-shift keying (DPSK) signals based on RF power detection is studied. The RF power spectrum is found to increase with the increase of CD and decrease with polarization mode dispersion (PMD). The spectral power density dependence on CD is studied theoretically and then verified through simulations and experiments. The monitoring sensitivity for nonreturn-to-zero differential phase-shift keying (NRZ-DPSK) and return-to-zero differential phase-shift keying (RZ-DPSK) based systems can reach 80ps/nm/dB and 34ps/nm/dB respectively. The scheme enables the monitoring of differential group delay (DGD) and CD simultaneously. The monitoring sensitivity of CD and DGD can reach 56.7ps/nm/dB and 3.1ps/dB using a bandpass filter. The effects of optical signal-to-noise ratio (OSNR), DGD, fiber nonlinearity and chirp on the monitoring results are investigated. Two RF pilot tones are employed for CD monitoring of DPSK signals. Specially selected pilot tone frequencies enable good monitoring sensitivity with minimum influence on the received signals. The dynamic range exceeding 35dB and monitoring sensitivity up to 9.5ps/nm/dB are achieved. Asynchronous sampling technique is employed for CD monitoring. A signed CD monitoring method for 10Gb/s NRZ-DPSK and RZ-DPSK systems using asynchronous delay-tap sampling technique is studied. The demodulated signals suffer asymmetric waveform distortion if there is a phase error (Deltaphi) in the delay interferometer (DI) and in the presence of residual CD. Using delay-tap sampling the scatter plots can reflect this signal distortion through their asymmetric characteristics. A distance ratio (DR) is defined to represent the change of the scatter plots which is directly related to the accumulated CD. The monitoring range can be up to +/-400ps/nm and to +/-720ps/nm for 10Gb/s NRZ-DPSK and RZ-DPSK signals with 450 phase error in DI. The monitoring sensitivity reaches +/-8ps/nm and CD polarity discrimination is realized. It is found that the signal degradation is related to the increment of the absolute value of CD or phase mismatch. The effect of different polarities of phase error on CD monitoring is also analyzed. The shoulders location depends on the sign of the product DLDeltaphi. If DLDeltaphi > 0, the shoulder will appear on trailing edge else the shoulder will appear on leading edge when DLDeltaphi < 0. The analysis shows that the phase error is identical to the frequency offset of optical source so a signed frequency offset monitoring is also demonstrated. The monitoring results show that the monitoring range can reach +/-2.2GHz and the monitoring sensitivity is around 27MHz. The effect of nonlinearity, OSNR and bandwidth of the lowpass filter on the proposed monitoring method has also been studied. The signed CD monitoring for 100Gb/s carrier suppressed return-to-zero differential quadrature phase-shift keying (CSRZ-DQPSK) system based on the delay-tap sampling technology is demonstrated. The monitoring range and monitoring resolution can goes up to +/-32ps/nm and +/-8ps/nm, respectively. A signed CD and optical carrier wavelength monitoring scheme using cross-correlation method for on-off keying (00K) wavelength division multiplexing (WDM) system is proposed and demonstrated. CD monitoring sensitivity is high and can be less than 10% of the bit period. Wavelength monitoring is implemented using the proposed approach. The monitoring results show that the sensitivity can reach up to 1.37ps/GHz.

The Effect of Combat on Aircrew Subjective Readiness and LSO Grades during Operation Desert Shield/Storm.

DTIC Science & Technology

1992-05-01

These periods of SUSOPS often require many hours of mission planning and briefing by the same aircrew who later fly into combat. This ’front-loading’ of...CsCOLLATERIAL OUTr. GDUTIDIES a au LE.P Sa PlKF PoSTRIKE PLANNING EXEsERCISE DATE MUEAS 0aEMMF PsMEOCEATIONIMEST XETESTING!11 11 I1illilll ii I-. II...duration and infrequent occurrence, functional check flights (FCF) and post maintenance check flights ( PMCF ) were also included among the TRG flights

Two reaction pathways for transformation of high potential cytochrome b559 of PS II into the intermediate potential form.

PubMed

Kaminskaya, Olga; Shuvalov, Vladimir A; Renger, Gernot

2007-06-01

This study describes an analysis of different treatments that influence the relative content and the midpoint potential of HP Cyt b559 in PS II membrane fragments from higher plants. Two basically different types of irreversible modification effects are distinguished: the HP form of Cyt b559 is either predominantly affected when the heme group is oxidized ("O-type" effects) or when it is reduced ("R-type" effects). Transformation of HP Cyt b559 to lower potential redox forms (IP and LP forms) by the "O-type" mechanism is induced by high pH and detergent treatments. In this case the effects consist of a gradual decrease in the relative content of HP Cyt b559 while its midpoint potential remains unaffected. Transformation of HP Cyt b559 via an "R-type" mechanism is caused by a number of exogenous compounds denoted L: herbicides, ADRY reagents and tetraphenylboron. These compounds are postulated to bind to the PS II complex at a quinone binding site designated as Q(C) which interacts with Cyt b559 and is clearly not the Q(B) site. Binding of compounds L to the Q(C) site when HP Cyt b559 is oxidized gives rise to a gradual decrease in the E(m) of HP Cyt b559 with increasing concentration of L (up to 10 K(ox)(L) values) while the relative content of HP Cyt b559 is unaffected. Higher concentrations of compounds L required for their binding to Q(C) site when HP Cyt b559 is reduced (described by K(red)(L)) induce a conversion of HP Cyt b559 to lower potential redox forms ("R-type" transformation). Two reaction pathways for transitions of Cyt b559 between the different protein conformations that are responsible for the HP and IP/LP redox forms are proposed and new insights into the functional regulation of Cyt b559 via the Q(C) site are discussed.

Phase-locked-loop-based delay-line-free picosecond electro-optic sampling system

NASA Astrophysics Data System (ADS)

Lin, Gong-Ru; Chang, Yung-Cheng

2003-04-01

A delay-line-free, high-speed electro-optic sampling (EOS) system is proposed by employing a delay-time-controlled ultrafast laser diode as the optical probe. Versatile optoelectronic delay-time controllers (ODTCs) based on modified voltage-controlled phase-locked-loop phase-shifting technologies are designed for the laser. The integration of the ODTC circuit and the pulsed laser diode has replaced the traditional optomechanical delay-line module used in the conventional EOS system. This design essentially prevents sampling distortion from misalignment of the probe beam, and overcomes the difficulty in sampling free-running high-speed transients. The maximum tuning range, error, scanning speed, tuning responsivity, and resolution of the ODTC are 3.9π (700°), <5% deviation, 25-2405 ns/s, 0.557 ps/mV, and ˜1 ps, respectively. Free-running wave forms from the analog, digital, and pulsed microwave signals are sampled and compared with those measured by the commercial apparatus.

Long-term Outcomes of One Stage Surgery Using Transanal Colorectal Tube for Acute Colorectal Obstruction of Stage II/III Distal Colon Cancer.

PubMed

Okuda, Yusuke; Yamada, Tomonori; Hirata, Yoshikazu; Shimura, Takaya; Yamaguchi, Ryuzo; Sakamoto, Eiji; Sobue, Satoshi; Nakazawa, Takahiro; Kataoka, Hiromi; Joh, Takashi

2018-06-06

Since oncological outcomes of transanal colorectal tube (TCT) placement, an endoscopic treatment for colorectal cancer (CRC) with acute colorectal obstruction (ACO), remain unknown, this study analyzed long-term outcomes of TCT placement for stage II/III CRC with ACO. Data were retrospectively reviewed from consecutive patients with distal stage II/III CRC who underwent surgery between January 2007 and December 2011 at two Japanese hospitals. One hospital conducted emergency surgery and the other performed TCT placement as the standard treatment for all CRCs with ACO. Propensity score (PS) matching was used to adjust baseline characteristics between two groups. Among 754 patients with distal stage II/III CRC, 680 did not have ACO (non-ACO group) and 74 had ACO (ACO group). The PS matching between both hospitals identified 234 pairs in the non-ACO group and 23 pairs in the ACO group. In the non-ACO group, the surgical quality was equivalent between the two institutions, with no significant differences in overall survival (OS) and disease-free survival (DFS). In the ACO group, the rate of primary resection/anastomosis was higher in the TCT group than in the surgery group (87.0% vs. 26.1%; p < 0.001). No significant differences were noted between the surgery and the TCT groups in OS (5-year OS, 61.9% vs. 51.5%; p=0.490) and DFS (5-year DFS, 45.9% vs. 38.3%; p=0.658). TCT placement can achieve similar long-term outcomes to emergency surgery, with a high rate of primary resection/anastomosis for distal stage II/III colon cancer with ACO.

Overexpression of Notch3 and pS6 Is Associated with Poor Prognosis in Human Ovarian Epithelial Cancer.

PubMed

Liu, Zhaoxia; Yun, Rongna; Yu, Xiaolin; Hu, Hui; Huang, Genhua; Tan, Buzhen; Chen, Tingtao

2016-01-01

Notch3 and pS6 play important roles in tumor angiogenesis. To assess the expression of Notch3 and pS6 in Chinese ovarian epithelial cancer patients, a ten-year follow-up study was performed in ovarian epithelial cancer tissues from 120 specimens of human ovarian epithelial cancer, 30 specimens from benign ovarian tumors, and 30 samples from healthy ovaries by immunohistochemistry. The results indicate that the expression of Notch3 and pS6 was higher in ovarian epithelial cancer than in normal ovary tissues and in benign ovarian tumor tissues (p < 0.01). In tumor tissues, Notch3 expression and pS6 expression were negatively associated with age (p > 0.05) but positively associated with clinical stage, pathological grading, histologic type, lymph node metastasis, and ascites (p < 0.05 or p < 0.01). A follow-up survey of 64 patients with ovarian epithelial cancer showed that patients with high Notch3 and pS6 expression had a shorter survival time (p < 0.01), in which the clinical stage (p < 0.05) and Notch3 expression (p < 0.01) played important roles. In conclusion, Notch3 and pS6 are significantly related to ovarian epithelial cancer development and prognosis, and their combination represents a potential biomarker and therapeutic target in ovarian tumor angiogenesis.

Using Integrative Data Analysis to Examine Changes in Alcohol Use and Changes in Sexual Risk Behavior across Four Samples of STI Clinic Patients

PubMed Central

Walsh, Jennifer L.; Weinhardt, Lance S.; Kalichman, Seth C.; Carey, Michael P.

2016-01-01

Background Patients in sexually transmitted infection (STI) clinics report high levels of alcohol use, which are associated with risky sexual behavior. However, no studies have examined how changes in alcohol use relate to changes in sexual risk behavior. Purpose We used parallel process latent growth modeling to explore how changes in alcohol use related to changes in sexual behavior across four samples of clinic patients. Methods Patients participating in HIV prevention trials from urban clinics in the Northeastern and Midwestern U.S. (N = 3,761, 59% male, 72% Black) completed measures at 3mo intervals over 9-12mo. Integrative data analysis was used to create composite measures of alcohol use across samples. Sexual risk measures were counts of partners and unprotected sex acts. Parallel process models tested whether alcohol use changes were correlated with changes in number of partners and unprotected sex. Results Growth models with good fit showed decreases that slowed over time in sexual risk behaviors and alcohol use. Parallel process models showed positive correlations between levels of (rs =.17-.40, ps < .001) and changes in (rs = .21-.80, ps < .05) alcohol use and number of sexual partners across studies. There were strong associations between levels of (rs = .25-.43, ps < .001) and changes in (rs = .24-.57, ps < .01) alcohol use and unprotected sex in one study recruiting hazardous drinkers. Conclusions Across four samples of clinic patients, reductions in alcohol use were associated with reductions in the number of sexual partners. HIV prevention interventions may be strengthened by addressing alcohol use. PMID:27550626

Evaluation of phosphatidylserine-dependent antiprothrombin antibody testing for the diagnosis of antiphospholipid syndrome: results of an international multicentre study.

PubMed

Amengual, O; Forastiero, R; Sugiura-Ogasawara, M; Otomo, K; Oku, K; Favas, C; Delgado Alves, J; Žigon, P; Ambrožič, A; Tomšič, M; Ruiz-Arruza, I; Ruiz-Irastorza, G; Bertolaccini, M L; Norman, G L; Shums, Z; Arai, J; Murashima, A; Tebo, A E; Gerosa, M; Meroni, P L; Rodriguez-Pintó, I; Cervera, R; Swadzba, J; Musial, J; Atsumi, T

2017-03-01

Objective A task force of scientists at the International Congress on Antiphospholipid Antibodies recognized that phosphatidylserine-dependent antiprothrombin antibodies (aPS/PT) might contribute to a better identification of antiphospholipid syndrome (APS). Accordingly, initial and replication retrospective, cross-sectional multicentre studies were conducted to ascertain the value of aPS/PT for APS diagnosis. Methods In the initial study (eight centres, seven countries), clinical/laboratory data were retrospectively collected. Serum/plasma samples were tested for IgG aPS/PT at Inova Diagnostics (Inova) using two ELISA kits. A replication study (five centres, five countries) was carried out afterwards. Results In the initial study ( n = 247), a moderate agreement between the IgG aPS/PT Inova and MBL ELISA kits was observed ( k = 0.598). IgG aPS/PT were more prevalent in APS patients (51%) than in those without (9%), OR 10.8, 95% CI (4.0-29.3), p < 0.0001. Sensitivity, specificity, positive (LR+) and negative (LR-) likelihood ratio of IgG aPS/PT for APS diagnosis were 51%, 91%, 5.9 and 0.5, respectively. In the replication study ( n = 214), a moderate/substantial agreement between the IgG aPS/PT results obtained with both ELISA kits was observed ( k = 0.630). IgG aPS/PT were more prevalent in APS patients (47%) than in those without (12%), OR 6.4, 95% CI (2.6-16), p < 0.0001. Sensitivity, specificity, LR + and LR- for APS diagnosis were 47%, 88%, 3.9 and 0.6, respectively. Conclusions IgG aPS/PT detection is an easily performed laboratory parameter that might contribute to a better and more complete identification of patients with APS.

A novel graphene-based label-free fluorescence `turn-on' nanosensor for selective and sensitive detection of phosphorylated species in biological samples and living cells

NASA Astrophysics Data System (ADS)

Ke, Yaotang; Garg, Bhaskar; Ling, Yong-Chien

2016-02-01

A novel label-free fluorescence `turn-on' nanosensor has been developed for highly selective and sensitive detection of phosphorylated species (Ps) in biological samples and living cells. The design strategy relies on the use of Ti4+-immobilized polydopamine (PDA) coated reduced graphene oxide (rGO@PDA-Ti4+) that serves as an attractive platform to bind riboflavin 5'-monophosphate molecules (FMNs) through ion-pair interactions between phosphate groups and Ti4+. The as-prepared rGO@PDA-Ti4+-FMNs (nanosensor), fluoresce only weakly due to the ineffective Förster resonance energy transfer between the FMNs and rGO@PDA-Ti4+. The experimental findings revealed that the microwave-assisted interaction of the nanosensor with α-, β-casein, ovalbumin, human serum, non-fat milk, egg white, and living cells (all containing Ps) releases FMNs (due to the high formation constant between phosphate groups and Ti4+), leading to an excellent fluorescence `turn-on' response. The fluorescence spectroscopy, confocal microscopy, and MALDI-TOF MS spectrometry were used to detect Ps both qualitatively and quantitatively. Under the optimized conditions, the nanosensor showed a detection limit of ca. 118.5, 28.9, and 54.8 nM for the tryptic digests of α-, β-casein and ovalbumin, respectively. Furthermore, the standard addition method was used as a bench-mark proof for phosphopeptide quantification in egg white samples. We postulate that the present quantitative assay for Ps holds tremendous potential and may pave the way to disease diagnostics in the near future.A novel label-free fluorescence `turn-on' nanosensor has been developed for highly selective and sensitive detection of phosphorylated species (Ps) in biological samples and living cells. The design strategy relies on the use of Ti4+-immobilized polydopamine (PDA) coated reduced graphene oxide (rGO@PDA-Ti4+) that serves as an attractive platform to bind riboflavin 5'-monophosphate molecules (FMNs) through ion-pair interactions between phosphate groups and Ti4+. The as-prepared rGO@PDA-Ti4+-FMNs (nanosensor), fluoresce only weakly due to the ineffective Förster resonance energy transfer between the FMNs and rGO@PDA-Ti4+. The experimental findings revealed that the microwave-assisted interaction of the nanosensor with α-, β-casein, ovalbumin, human serum, non-fat milk, egg white, and living cells (all containing Ps) releases FMNs (due to the high formation constant between phosphate groups and Ti4+), leading to an excellent fluorescence `turn-on' response. The fluorescence spectroscopy, confocal microscopy, and MALDI-TOF MS spectrometry were used to detect Ps both qualitatively and quantitatively. Under the optimized conditions, the nanosensor showed a detection limit of ca. 118.5, 28.9, and 54.8 nM for the tryptic digests of α-, β-casein and ovalbumin, respectively. Furthermore, the standard addition method was used as a bench-mark proof for phosphopeptide quantification in egg white samples. We postulate that the present quantitative assay for Ps holds tremendous potential and may pave the way to disease diagnostics in the near future. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr07261a

Non-oxidized porous silicon-based power AC switch peripheries.

PubMed

Menard, Samuel; Fèvre, Angélique; Valente, Damien; Billoué, Jérôme; Gautier, Gaël

2012-10-11

We present in this paper a novel application of porous silicon (PS) for low-power alternating current (AC) switches such as triode alternating current devices (TRIACs) frequently used to control small appliances (fridge, vacuum cleaner, washing machine, coffee makers, etc.). More precisely, it seems possible to benefit from the PS electrical insulation properties to ensure the OFF state of the device. Based on the technological aspects of the most commonly used AC switch peripheries physically responsible of the TRIAC blocking performances (leakage current and breakdown voltage), we suggest to isolate upper and lower junctions through the addition of a PS layer anodically etched from existing AC switch diffusion profiles. Then, we comment the voltage capability of practical samples emanating from the proposed architecture. Thanks to the characterization results of simple Al-PS-Si(P) structures, the experimental observations are interpreted, thus opening new outlooks in the field of AC switch peripheries.

Synthesis, characterization and single crystal x-ray analysis of a complex of iron(II) bis(2,4-dimethylphenyl)dithiophosphate with 4-ethylpyridine

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

Kumar, Sandeep; Andotra, Savit; Kaur, Mandeep

2016-09-15

Complex of iron(II) bis(2,4-dimethylphenyl)dithiophosphate with 4-ethylpyridine [((2,4- (CH{sub 3}){sub 2}C{sub 6}H{sub 3}O)2PS2)2Fe(NC{sub 5}H{sub 4}(C{sub 2}H{sub 5})-4){sub 2}] is synthesized and characterized by elemental analysis, magnetic moment, IR spectroscopy and single crystal X-ray analysis. Complex crystallizes in the monoclinic sp. gr. P2{sub 1}/n, Z = 2. Crystal structure consists of mononuclear units with Fe(II) ion chelated by four S atoms of the two diphenyldithiophosphate ligands in bidentate manner. N atoms from two 4-ethylpyridine ligands are axially coordinated to the Fe(II) atom leading to an octahedral geometry.

Dynamics of spallation during femtosecond laser ablation studied by time-resolved reflectivity with double pump pulses

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

Kumada, Takayuki, E-mail: kumada.takayuki@jaea.go.jp; Otobe, Tomohito; Nishikino, Masaharu

2016-01-04

The dynamics of photomechanical spallation during femtosecond laser ablation of fused silica was studied by time-resolved reflectivity with double pump pulses. Oscillation of reflectivity was caused by interference between the probe pulses reflected at the sample surface and the spallation layer, and was enhanced when the surface was irradiated with the second pump pulse within a time interval, Δτ, of several picoseconds after the first pump pulse. However, as Δτ was increased, the oscillation amplitude decreased with an exponential decay time of 10 ps. The oscillation disappeared when Δτ exceeded 20 ps. This result suggests that the formation time of the spallationmore » layer is approximately 10 ps. A second pump pulse with Δτ shorter than 10 ps excites the bulk sample. The spallation layer that is photo-excited by the first and second pump pulses is separated afterward. In contrast, a pulse with Δτ longer than the formation time excites and breaks up the spallation layer that has already been separated from the bulk. The formation time of the spallation layer, as determined in this experiment, is attributed to the characteristic time of the mechanical equilibration corresponding to the thickness divided by the sound velocity of the photo-excited layer.« less

Bioinspired polydopamine sheathed nanofibers for high-efficient in vivo solid-phase microextraction of pharmaceuticals in fish muscle.

PubMed

Xu, Jianqiao; Huang, Shuyao; Wu, Rongben; Jiang, Ruifen; Zhu, Fang; Wang, Jing; Ouyang, Gangfeng

2015-03-17

In this study, electrospun nanofibers were used as solid-phase microextraction (SPME) fiber coatings after substituting the water-soluble sheath of the emulsion electrospun polystyrene (PS)@Plurinic F-127 core-sheath nanofibers with biocompatible and water-stable polydopamine (PDA) and subsequently being appropriately cross-linked with glutaraldehyde (GA) to enhance the strength of the electrospun architecture. The novel custom-made PS@PDA-GA coating was wettable in aqueous solutions and thus exhibited much higher extraction efficiency than the nonsheathed PS nanofiber coating and the thicker polydimethylsiloxane (PDMS) coating. The novel coating also possessed excellent stability (relative standard deviations (RSDs) less than 7.3% for six sampling-desorption cycles), interfiber reproducibility (RSDs less than 14.3%), and antibiofouling ability, which were beneficial for in vivo sampling. The PS@PDA-GA fiber was used to monitor pharmaceuticals in dorsal-epaxial muscle of living fish, and satisfactory sensitivities with the limits of detection in the range of 1.1 (mefenamic acid) to 8.9 (fluoxetine) ng·g(-1) and comparable accuracies to liquid extraction were achieved. In general, this study explored a convenient and effective method to sheath nanofibers for high-efficient in vivo SPME of analytes of interest in semisolid tissues.

Nanodiamond infiltration into porous silicon through etching of solid carbon produced at different graphitization temperatures

NASA Astrophysics Data System (ADS)

Miranda, C. R. B.; Baldan, M. R.; Beloto, A. F.; Ferreira, N. G.

2011-09-01

Nanocrystalline diamond (NCD) was grown on the porous silicon (PS) substrate using Reticulated Vitreous Carbon (RVC) as an additional solid carbon source. RVC was produced at different heat treatment temperatures of 1300, 1500, and 2000 °C, resulting in samples with different turbostratic carbon organizations. The PS substrate was produced by an electrochemical method. NCD film was obtained by the chemical vapor infiltration/deposition process where a RVC piece was positioned just below the PS substrate. The PS and NCD samples were characterized by Field Emission Gun-Scanning Electron Microscopy (FEG-SEM). NCD films presented faceted nanograins with uniform surface texture covering all the pores resulting in an apparent micro honeycomb structure. Raman's spectra showed the D and G bands, as well as, the typical two shoulders at 1,150 and 1,490 cm-1 attributed to NCD. X-ray diffraction analyses showed the predominant (111) diamond orientation as well as the (220) and (311) peaks. The structural organization and the heteroatom presence on the RVC surface, analyzed from X-ray photoelectron spectroscopy, showed their significant influence on the NCD growth process. The hydrogen etching released, from RVC surface, associated to carbon and/or oxygen/nitrogen amounts led to different contributions for NCD growth.

Biogenic synthesis of Fe3O4 magnetic nanoparticles using Pisum sativum peels extract and its effect on magnetic and Methyl orange dye degradation studies

NASA Astrophysics Data System (ADS)

Prasad, Cheera; Yuvaraja, Gutha; Venkateswarlu, Ponneri

2017-02-01

We have been developed facile and ecofriendly method for the synthesis of Fe3O4 magnetic nanoparticles (MNPs) using an aqueous extract of Pisum sativum peels (PS) is used as reducing and capping agent. The as synthesized PS-Fe3O4 MNPs are characterized by diverse techniques such as FTIR, powder XRD, TEM, BET and Raman spectroscopy measurements. The results show that the obtained Fe3O4 nanoparticles exhibits high specific surface area (∼17.6 m2/g) and agglomerated spherical in shape with the size range of 20-30 nm. The magnetic properties of PS-Fe3O4 MNPs sample clearly exhibits ferromagnetic nature with a saturation magnetization of 64.2 emu/g. Further, the catalytic properties of PS-Fe3O4 MNPs for degradation of Methyl orange (MO) dye in aqueous solution have been investigated by UV-visible spectroscopy. The results show that PS-Fe3O4 MNPs is an efficient catalyst for degradation of Methyl orange dye than previously reported ones.

Quantifying the remineralization of artificial caries lesions using PS-OCT

NASA Astrophysics Data System (ADS)

Jones, Robert S.; Fried, Daniel

2006-02-01

New optical imaging methods are needed to determine whether caries lesions (tooth decay) are active and progressing or have become remineralized and arrested and are no longer progressing. The objective of this study was to use Polarization Sensitive Optical Coherence Tomography (PS-OCT) to image the fluoride enhanced remineralization of artificial enamel lesions. Artificial lesions were created by an acetate buffer on smooth enamel surfaces and were exposed for 20 days to a 2 ppm fluoride containing remineralization solution. PS-OCT images revealed the presence of a low scattering surface zone after the artificial lesions were remineralized. These samples displayed intact nondepolarizing surface zones when analyzed with Polarized Light Microscopy (PLM). No statistical difference in lesion depth before and after remineralization was found with both PS-OCT and PLM. The remineralized lesions showed a significant decrease in the overall integrated reflectivity compared with the demineralized lesions. Digital Microradiography confirmed the increase in mineral volume of the remineralized surface zone. This study determined that PS-OCT can image the restoration of the surface zone enamel after fluoride-enhanced remineralization of artificial in vitro dental caries.

Theory of Positron Annihilation in Helium-Filled Bubbles in Plutonium

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

Sterne, P A; Pask, J E

2003-02-13

Positron annihilation lifetime spectroscopy is a sensitive probe of vacancies and voids in materials. This non-destructive measurement technique can identify the presence of specific defects in materials at the part-per-million level. Recent experiments by Asoka-Kumar et al. have identified two lifetime components in aged plutonium samples--a dominant lifetime component of around 182 ps and a longer lifetime component of around 350-400ps. This second component appears to increase with the age of the sample, and accounts for only about 5 percent of the total intensity in 35 year-old plutonium samples. First-principles calculations of positron lifetimes are now used extensively to guidemore » the interpretation of positron lifetime data. At Livermore, we have developed a first-principles finite-element-based method for calculating positron lifetimes for defects in metals. This method is capable of treating system cell sizes of several thousand atoms, allowing us to model defects in plutonium ranging in size from a mono-vacancy to helium-filled bubbles of over 1 nm in diameter. In order to identify the defects that account for the observed lifetime values, we have performed positron lifetime calculations for a set of vacancies, vacancy clusters, and helium-filled vacancy clusters in delta-plutonium. The calculations produced values of 143ps for defect-free delta-Pu and 255ps for a mono-vacancy in Pu, both of which are inconsistent with the dominant experimental lifetime component of 182ps. Larger vacancy clusters have even longer lifetimes. The observed positron lifetime is significantly shorter than the calculated lifetimes for mono-vacancies and larger vacancy clusters, indicating that open vacancy clusters are not the dominant defect in the aged plutonium samples. When helium atoms are introduced into the vacancy cluster, the positron lifetime is reduced due to the increased density of electrons available for annihilation. For a mono-vacancy in Pu containing one helium atom, the calculated lifetime is 190 ps, while a di-vacancy containing two helium atoms has a positron lifetime of 205 ps. In general, increasing the helium density in a vacancy cluster or He-filled bubble reduces the positron lifetime, so that the same lifetime value can arise fi-om a range of vacancy cluster sizes with different helium densities. In order to understand the variation of positron lifetime with vacancy cluster size and helium density in the defect, we have performed over 60 positron lifetime calculations with vacancy cluster sizes ranging from 1 to 55 vacancies and helium densities ranging fi-om zero to five helium atoms per vacancy. The results indicate that the experimental lifetime of 182 ps is consistent with the theoretical value of 190 ps for a mono-vacancy with a single helium atom, but that slightly better agreement is obtained for larger clusters of 6 or more vacancies containing 2-3 helium atoms per vacancy. For larger vacancy clusters with diameters of about 3-5 nm or more, the annihilation with helium electrons dominates the positron annihilation rate; the observed lifetime of 180ps is then consistent with a helium concentration in the range of 3 to 3.5 Hehacancy, setting an upper bound on the helium concentration in the vacancy clusters. In practice, the single lifetime component is most probably associated with a family of helium-filled bubbles rather than with a specific unique defect size. The longer 350-400ps lifetime component is consistent with a relatively narrow range of defect sizes and He concentration. At zero He concentration, the lifetime values are matched by small vacancy clusters containing 6-12 vacancies. With increasing vacancy cluster size, a small amount of He is required to keep the lifetime in the 350-400 ps range, until the value saturates for larger helium bubbles of more than 50 vacancies (bubble diameter > 1.3 nm) at a helium concentration close to 1 He/vacancy. These results, taken together with the experimental data, indicate that the features observed in TEM data by Schwartz et al are not voids, but are in fact helium-filled bubbles with a helium pressure of around 2-3 helium atoms per vacancy, depending on the bubble size. This is consistent with the conclusions of recently developed models of He-bubble growth in aged plutonium.« less

A Facile Method to Establish Human Induced Pluripotent Stem Cells From Adult Blood Cells Under Feeder-Free and Xeno-Free Culture Conditions: A Clinically Compliant Approach

PubMed Central

Chou, Bin-Kuan; Gu, Haihui; Gao, Yongxing; Dowey, Sarah N.; Wang, Ying; Shi, Jun; Li, Yanxin; Ye, Zhaohui; Cheng, Tao

2015-01-01

Reprogramming human adult blood mononuclear cells (MNCs) cells by transient plasmid expression is becoming increasingly popular as an attractive method for generating induced pluripotent stem (iPS) cells without the genomic alteration caused by genome-inserting vectors. However, its efficiency is relatively low with adult MNCs compared with cord blood MNCs and other fetal cells and is highly variable among different adult individuals. We report highly efficient iPS cell derivation under clinically compliant conditions via three major improvements. First, we revised a combination of three EBNA1/OriP episomal vectors expressing five transgenes, which increased reprogramming efficiency by ≥10–50-fold from our previous vectors. Second, human recombinant vitronectin proteins were used as cell culture substrates, alleviating the need for feeder cells or animal-sourced proteins. Finally, we eliminated the previously critical step of manually picking individual iPS cell clones by pooling newly emerged iPS cell colonies. Pooled cultures were then purified based on the presence of the TRA-1-60 pluripotency surface antigen, resulting in the ability to rapidly expand iPS cells for subsequent applications. These new improvements permit a consistent and reliable method to generate human iPS cells with minimal clonal variations from blood MNCs, including previously difficult samples such as those from patients with paroxysmal nocturnal hemoglobinuria. In addition, this method of efficiently generating iPS cells under feeder-free and xeno-free conditions allows for the establishment of clinically compliant iPS cell lines for future therapeutic applications. PMID:25742692

Sustaining quality improvement and patient safety training in graduate medical education: lessons from social theory.

PubMed

Wong, Brian M; Kuper, Ayelet; Hollenberg, Elisa; Etchells, Edward E; Levinson, Wendy; Shojania, Kaveh G

2013-08-01

Despite an official mandate to incorporate formal quality improvement (QI) and patient safety (PS) training into graduate medical education, many QI/PS curricular efforts face implementation challenges and are not sustained. Educators are increasingly turning to sociocultural theories to address issues such as curricular uptake in medical education. The authors conducted a case study using Bourdieu's concepts of "field" and "habitus" to identify theoretically derived strategies that can promote sustained implementation of QI/PS curricula. From October 2010 through May 2011, the authors conducted semistructured interviews with principal authors of studies included in a systematic review of QI/PS curricula and with key informants (identified by study participants) who did not publish on their QI/PS curricular efforts. The authors purposively sampled to theoretical saturation and analyzed data concurrently with iterative data gathering within Bourdieu's theoretical framework. The study included 16 participants representing six specialties in the United States and Canada. Data analysis revealed that academic physicians belong to, and compete for legitimate forms of capital within, two separate but related fields associated with QI/PScurricular implementation: the "academic field" and the "health care delivery field." Respondents used specific strategies toexploit and/or redefine the prevailingforms of legitimate capital in each field to encourage changes inacademic physicians' habitus that would legitimizeQI/PS. Situating study findings in a sociocultural theory enables articulation of concrete strategies that can legitimize QI/PS in the academic and health care delivery fields. These strategies can promote sustained QI/PS curricula in graduate medical education.

Measurement of the Bs0-Bs0 oscillation frequency.

PubMed

Abulencia, A; Acosta, D; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arguin, J-F; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Belloni, A; Ben Haim, E; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carlsmith, D; Carosi, R; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chapman, J; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Chu, P H; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciljak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cruz, A; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cyr, D; DaRonco, S; D'Auria, S; D'Onofrio, M; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; Dell'Orso, M; Delli Paoli, F; Demers, S; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Di Ruzza, B; Dionisi, C; Dittmann, J R; DiTuro, P; Dörr, C; Donati, S; Donega, M; Dong, P; Donini, J; Dorigo, T; Dube, S; Ebina, K; Efron, J; Ehlers, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Frisch, H J; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garcia Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giokaris, N; Giolo, K; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Griffiths, M; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, S R; Hahn, K; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harper, S; Harr, R F; Harris, R M; Hatakeyama, K; Hauser, J; Hays, C; Heijboer, A; Heinemann, B; Heinrich, J; Herndon, M; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jensen, H; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kamon, T; Kang, J; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kobayashi, H; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kovalev, A; Kraan, A; Kraus, J; Kravchenko, I; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Liss, T M; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Maki, T; Maksimovic, P; Malde, S; Manca, G; Margaroli, F; Marginean, R; Marino, C; Martin, A; Martin, V; Martínez, M; Maruyama, T; Mastrandrea, P; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; von der Mey, M; Miao, T; Miladinovic, N; Miles, J; Miller, R; Miller, J S; Mills, C; Milnik, M; Miquel, R; Mitra, A; Mitselmakher, G; Miyamoto, A; Moggi, N; Mohr, B; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Nachtman, J; Naganoma, J; Nahn, S; Nakano, I; Napier, A; Naumov, D; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nigmanov, T; Nodulman, L; Norniella, O; Nurse, E; Ogawa, T; Oh, S H; Oh, Y D; Okusawa, T; Oldeman, R; Orava, R; Osterberg, K; Pagliarone, C; Palencia, E; Paoletti, R; Papadimitriou, V; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Rakitin, A; Rappoccio, S; Ratnikov, F; Reisert, B; Rekovic, V; van Remortel, N; Renton, P; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robertson, W J; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Rott, C; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Sabik, S; Safonov, A; Sakumoto, W K; Salamanna, G; Saltó, O; Saltzberg, D; Sanchez, C; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfiligoi, I; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Sjolin, J; Skiba, A; Slaughter, A J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spezziga, M; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sumorok, K; Sun, H; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tanimoto, N; Tecchio, M; Teng, P K; Terashi, K; Tether, S; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Tönnesmann, M; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tsuchiya, R; Tsuno, S; Turini, N; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vaiciulis, A; Vallecorsa, S; Varganov, A; Vataga, E; Velev, G; Veramendi, G; Veszpremi, V; Vidal, R; Vila, I; Vilar, R; Vine, T; Vollrath, I; Volobouev, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wallny, R; Walter, T; Wan, Z; Wang, S M; Warburton, A; Waschke, S; Waters, D; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zetti, F; Zhang, X; Zhou, J; Zucchelli, S

2006-08-11

We present the first precise measurement of the Bs0-Bs0 oscillation frequency Deltams. We use 1 fb-1 of data from pp collisions at sqrts=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. The sample contains signals of 3600 fully reconstructed hadronic Bs decays and 37,000 partially reconstructed semileptonic Bs decays. We measure the probability as a function of proper decay time that the Bs decays with the same, or opposite, flavor as the flavor at production, and we find a signal consistent with Bs0-Bs0 oscillations. The probability that random fluctuations could produce a comparable signal is 0.2%. Under the hypothesis that the signal is due to Bs0-Bs0 oscillations, we measure Deltams=17.31(-0.18)+0.33(stat)+/-0.07(syst) ps-1 and determine |Vtd/Vts|=0.208(-0.002)+0.001(expt)-0.006(+0.008)(theor).

Measurements and FLUKA simulations of bismuth and aluminium activation at the CERN Shielding Benchmark Facility (CSBF)

NASA Astrophysics Data System (ADS)

Iliopoulou, E.; Bamidis, P.; Brugger, M.; Froeschl, R.; Infantino, A.; Kajimoto, T.; Nakao, N.; Roesler, S.; Sanami, T.; Siountas, A.

2018-03-01

The CERN High Energy AcceleRator Mixed field facility (CHARM) is located in the CERN Proton Synchrotron (PS) East Experimental Area. The facility receives a pulsed proton beam from the CERN PS with a beam momentum of 24 GeV/c with 5 ṡ1011 protons per pulse with a pulse length of 350 ms and with a maximum average beam intensity of 6.7 ṡ1010 p/s that then impacts on the CHARM target. The shielding of the CHARM facility also includes the CERN Shielding Benchmark Facility (CSBF) situated laterally above the target. This facility consists of 80 cm of cast iron and 360 cm of concrete with barite concrete in some places. Activation samples of bismuth and aluminium were placed in the CSBF and in the CHARM access corridor in July 2015. Monte Carlo simulations with the FLUKA code have been performed to estimate the specific production yields for these samples. The results estimated by FLUKA Monte Carlo simulations are compared to activation measurements of these samples. The comparison between FLUKA simulations and the measured values from γ-spectrometry gives an agreement better than a factor of 2.

Effects of light, food availability and temperature stress on the function of photosystem II and photosystem I of coral symbionts.

PubMed

Hoogenboom, Mia O; Campbell, Douglas A; Beraud, Eric; Dezeeuw, Katrina; Ferrier-Pagès, Christine

2012-01-01

Reef corals are heterotrophic coelenterates that achieve high productivity through their photosynthetic dinoflagellate symbionts. Excessive seawater temperature destabilises this symbiosis and causes corals to "bleach," lowering their photosynthetic capacity. Bleaching poses a serious threat to the persistence of coral reefs on a global scale. Despite expanding research on the causes of bleaching, the mechanisms remain a subject of debate. This study determined how light and food availability modulate the effects of temperature stress on photosynthesis in two reef coral species. We quantified the activities of Photosystem II, Photosystem I and whole chain electron transport under combinations of normal and stressful growth temperatures, moderate and high light levels and the presence or absence of feeding of the coral hosts. Our results show that PS1 function is comparatively robust against temperature stress in both species, whereas PS2 and whole chain electron transport are susceptible to temperature stress. In the symbiotic dinoflagellates of Stylophora pistillata the contents of chlorophyll and major photosynthetic complexes were primarily affected by food availability. In Turbinaria reniformis growth temperature was the dominant influence on the contents of the photosynthetic complexes. In both species feeding the host significantly protected photosynthetic function from high temperature stress. Our findings support the photoinhibition model of coral bleaching and demonstrate that PS1 is not a major site for thermal damage during bleaching events. Feeding mitigates bleaching in two scleractinian corals, so that reef responses to temperature stresses will likely be influenced by the coinciding availabilities of prey for the host.

Metatranscriptomics of N2-fixing cyanobacteria in the Amazon River plume

PubMed Central

Hilton, Jason A; Satinsky, Brandon M; Doherty, Mary; Zielinski, Brian; Zehr, Jonathan P

2015-01-01

Biological N2 fixation is an important nitrogen source for surface ocean microbial communities. However, nearly all information on the diversity and gene expression of organisms responsible for oceanic N2 fixation in the environment has come from targeted approaches that assay only a small number of genes and organisms. Using genomes of diazotrophic cyanobacteria to extract reads from extensive meta-genomic and -transcriptomic libraries, we examined diazotroph diversity and gene expression from the Amazon River plume, an area characterized by salinity and nutrient gradients. Diazotroph genome and transcript sequences were most abundant in the transitional waters compared with lower salinity or oceanic water masses. We were able to distinguish two genetically divergent phylotypes within the Hemiaulus-associated Richelia sequences, which were the most abundant diazotroph sequences in the data set. Photosystem (PS)-II transcripts in Richelia populations were much less abundant than those in Trichodesmium, and transcripts from several Richelia PS-II genes were absent, indicating a prominent role for cyclic electron transport in Richelia. In addition, there were several abundant regulatory transcripts, including one that targets a gene involved in PS-I cyclic electron transport in Richelia. High sequence coverage of the Richelia transcripts, as well as those from Trichodesmium populations, allowed us to identify expressed regions of the genomes that had been overlooked by genome annotations. High-coverage genomic and transcription analysis enabled the characterization of distinct phylotypes within diazotrophic populations, revealed a distinction in a core process between dominant populations and provided evidence for a prominent role for noncoding RNAs in microbial communities. PMID:25514535

NOAA Photo Library

Science.gov Websites

NOAA Photo Library Banner Takes you to the Top Page Takes you to the About this Site page. Takes Collections page. Takes you to the search page. Takes you to the Links page. NOAA Photo Library Image the late Dr. Benjamin Franklin ....", 1806. Volume II, p. 26. Library Call Number PS745 .A2 1806

The regulation of TiO2 nanoparticles on the expression of light-harvesting complex II and photosynthesis of chloroplasts of Arabidopsis thaliana.

PubMed

Ze, Yuguan; Liu, Chao; Wang, Ling; Hong, Mengmeng; Hong, Fashui

2011-11-01

Recent studies demonstrated that titanium dioxide nanoparticles (TiO2 NPs) could significantly promote photosynthesis and plant growth, but its mechanism is still unclear. In this article, we studied the mechanism of light absorption and transfer of chloroplasts of Arabidopsis thaliana caused by TiO2 NPs treated. The results showed that TiO2 NPs could induce significant increases of light-harvesting complex II (LHCII) b gene expression and LHCII II content on the thylakoid membrane in A. thaliana, and the increases in LHCII were higher than the non-nano TiO2 (bulk-TiO2) treatment. Meanwhile, spectroscopy assays indicated that TiO2 NPs obviously increased the absorption peak intensity of the chloroplast in red and blue region, the fluorescence quantum yield near 680 nm, the excitation peak intensity near 440 and 480 nm and/or near 650 and 680 nm of the chloroplast. TiO2 NPs treatment could reduce F480/F440 ratio and increase F650/F680 ratio and accelerate the rate of whole chain electron transport and oxygen evolution of the chloroplast. However, the photosynthesis improvement of the non-nanoTiO2 treatment was far less effective than TiO2 NPs treatment. Taken together, TiO2 NPs could promote the light absorption of chloroplast, regulate the distribution of light energy from PS I to PS II by increasing LHCII and accelerate the transformation from light energy to electronic energy, water photolysis, and oxygen evolution.

Rating health and stability of engineering structures via classification indexes of InSAR Persistent Scatterers

NASA Astrophysics Data System (ADS)

Pratesi, Fabio; Tapete, Deodato; Terenzi, Gloria; Del Ventisette, Chiara; Moretti, Sandro

2015-08-01

We propose a novel set of indexes to classify the information content of Persistent Scatterers (PS) and rate the health of engineering structures at urban to local scale. PS are automatically sampled and grouped via 'control areas' coinciding with the building and its surrounding environment. Density over the 'control areas' and velocity of PS are converted respectively into: Completeness of Information Index (Ici) that reflects the PS coverage grade; and Conservation Criticality Indexes (Icc) which rate the health condition of the monument separately for the object and surrounding control areas. The deformation pattern over the structure is classified as isolated (i) or diffused (d) based on the Velocity Distribution Index (Ivd). Both Ici and Icc are rated from A to E classes using a colour-coded system that intentionally emulates an energy-efficiency scale, to encourage the exploitation of PS by stakeholders and end-users in the practise of engineering surveying. Workability and reliability of the classification indexes are demonstrated over the urban heritage of Florence, Italy, using well established ERS-1/2 (1992-2000) descending, ENVISAT (2003-2010) ascending and descending PS datasets. The indexes are designed in perspective of handling outputs from InSAR processing of higher-resolution time series.

Polarization sensitive spectroscopic optical coherence tomography for multimodal imaging

NASA Astrophysics Data System (ADS)

Strąkowski, Marcin R.; Kraszewski, Maciej; Strąkowska, Paulina; Trojanowski, Michał

2015-03-01

Optical coherence tomography (OCT) is a non-invasive method for 3D and cross-sectional imaging of biological and non-biological objects. The OCT measurements are provided in non-contact and absolutely safe way for the tested sample. Nowadays, the OCT is widely applied in medical diagnosis especially in ophthalmology, as well as dermatology, oncology and many more. Despite of great progress in OCT measurements there are still a vast number of issues like tissue recognition or imaging contrast enhancement that have not been solved yet. Here we are going to present the polarization sensitive spectroscopic OCT system (PS-SOCT). The PS-SOCT combines the polarization sensitive analysis with time-frequency analysis. Unlike standard polarization sensitive OCT the PS-SOCT delivers spectral information about measured quantities e.g. tested object birefringence changes over the light spectra. This solution overcomes the limits of polarization sensitive analysis applied in standard PS-OCT. Based on spectral data obtained from PS-SOCT the exact value of birefringence can be calculated even for the objects that provide higher order of retardation. In this contribution the benefits of using the combination of time-frequency and polarization sensitive analysis are being expressed. Moreover, the PS-SOCT system features, as well as OCT measurement examples are presented.

Persistent organic pollutants in plastic marine debris found on beaches in San Diego, California.

PubMed

Van, Almira; Rochman, Chelsea M; Flores, Elisa M; Hill, Kish L; Vargas, Erica; Vargas, Serena A; Hoh, Euhna

2012-01-01

Plastic debris were collected from eight beaches around San Diego County, California. Debris collected include: pre-production pellets and post-consumer plastics including fragments, polystyrene (PS) foam, and rubber. A total of n = 2453 pieces were collected ranging from <5 mm to 50 mm in size. The plastic pieces were separated by type, location, and appearance and analyzed for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its breakdown products, and chlordanes. PAH concentrations ranged from 30 ng g(-1) to 1900 ng g(-1), PCBs from non-detect to 47 ng g(-1), chlordanes from 1.8 ng g(-1) to 60 ng g(-1), and DDTs from non-detect to 76 ng g(-1). Consistently higher PAH concentrations found in PS foam samples (300-1900 ng g(-1)) led us to examine unexposed PS foam packaging materials and PS virgin pellets. Unexposed PS foam contained higher concentrations of PAHs (240-1700 ng g(-1)) than PS virgin pellets (12-15 ng g(-1)), suggesting that PAHs may be produced during manufacturing. Temporal trends of debris were investigated at one site, Ocean Beach, where storm events and beach maintenance were found to be important variables influencing debris present at a given time. Copyright © 2011 Elsevier Ltd. All rights reserved.

Modeling the photoacoustic signal during the porous silicon formation

NASA Astrophysics Data System (ADS)

Ramirez-Gutierrez, C. F.; Castaño-Yepes, J. D.; Rodriguez-García, M. E.

2017-01-01

Within this work, the kinetics of the growing stage of porous silicon (PS) during the etching process was studied using the photoacoustic technique. A p-type Si with low resistivity was used as a substrate. An extension of the Rosencwaig and Gersho model is proposed in order to analyze the temporary changes that take place in the amplitude of the photoacoustic signal during the PS growth. The solution of the heat equation takes into account the modulated laser beam, the changes in the reflectance of the PS-backing heterostructure, the electrochemical reaction, and the Joule effect as thermal sources. The model includes the time-dependence of the sample thickness during the electrochemical etching of PS. The changes in the reflectance are identified as the laser reflections in the internal layers of the system. The reflectance is modeled by an additional sinusoidal-monochromatic light source and its modulated frequency is related to the velocity of the PS growth. The chemical reaction and the DC components of the heat sources are taken as an average value from the experimental data. The theoretical results are in agreement with the experimental data and hence provided a method to determine variables of the PS growth, such as the etching velocity and the thickness of the porous layer during the growing process.

Effect of field cooling heights on the levitation force of pure and starch/polystyrene/MWCNT added bulk MgB2 superconductors

NASA Astrophysics Data System (ADS)

Tripathi, D.; Dey, T. K.

2014-12-01

A series of MgB2 pellets with and without addition of carbon from different sources (viz. starch, polystyrene and carbon nanotubes) have been synthesized by solid state reaction under argon atmosphere. XRD analysis indicates a decrease in lattice parameters of MgB2 with addition of starch, polystyrene (PS) and MWCNT and confirms substitution of carbon in boron sites. The presence of nanosized carbon inclusions between the grain boundaries in the present set of samples is evident in TEM photographs. Resistivity data confirms a decrease in superconducting transition temperature (Tc0) for MgB2 doped with starch/PS/MWCNT. The effect of different field cooling heights (HIFC) at 20 K on maximum levitation force (FMLF) and maximum attractive force (FMAF) of pure MgB2 and MgB2 doped with starch/PS/MWCNT have been investigated. Except for MWCNT, doping of starch and PS in MgB2 is found to improve FMLF and FMAF and the best result is obtained for MgB2 doped with 1 wt.% PS. Levitation force measured as a function of decreasing initial field cooling height indicates exponential dependence of both maximum levitation force (FMLF) and maximum attractive force (FMAF). However, the gap distance between PM and the sample (H0AF and HMAF) corresponding to maximum attractive force (FMAF) and zero attractive force (F0AF) varies linearly and their difference remains constant. This constancy in (HMAF - H0AF) is understood in terms of constant reduction rate of magnetic flux density between H0AF and HMAF.

Distribution of methicillin-resistant coagulase-positive staphylococci (MRCoPS) in a surgical unit and cystotomy operation sites in a veterinary teaching hospital

PubMed Central

FUNGWITHAYA, Punpichaya; BRIKSHAVANA, Pasakorn; CHANCHAITHONG, Pattrarat; PRAPASARAKUL, Nuvee

2016-01-01

This study aimed to investigate the spread of methicillin-resistant coagulase-positive staphylococci (MRCoPS) among veterinary staff, hand-touch sites and surgical tissue during cystotomy operations on cats and dogs that were patients, and to analyze the genetic relatedness and antimicrobial resistance profiles of the isolates. Human and environmental samples were obtained from the nasal passageways of 12 surgeons and veterinary assistants and from 29 hand-touch sites of instruments in operative units and subjected to bacterial isolation and enumeration. Swab samples were collected in triplicate from 29 dogs and three cats at the site of incision, from the incision area, from the peritoneum during surgery and from the peritoneum before suture. MRCoPS were identified by mecA gene detection and characterized by their antibiogram profile, SCCmec type and pulsed-field gel electrophoresis. Twenty-four staphylococci were isolated, derived from one veterinary assistant, 12 operating room floor areas and hand-touch sites, three dogs and one cat. Methicillin-resistant S. pseudintermedius (MRSP) was found on an electric clipper and rebreathing circuits in the operating room. Three dogs were positive for MRSP during surgery, and one methicillin-resistant S. aureus (MRSA) was detected in a cat. All MRCoPS were resistant to doxycycline, erythromycin, clindamycin and enrofloxacin, but no patients developed surgical site infections. According to their genotypic patterns, the clones obtained from the environment and human sources differed from the animal clones. Despite intensive hygienic management, a variety of MRCoPS clones were present within the surgical unit and during surgery. PMID:27990009

Distribution of methicillin-resistant coagulase-positive staphylococci (MRCoPS) in a surgical unit and cystotomy operation sites in a veterinary teaching hospital.

PubMed

Fungwithaya, Punpichaya; Brikshavana, Pasakorn; Chanchaithong, Pattrarat; Prapasarakul, Nuvee

2017-02-28

This study aimed to investigate the spread of methicillin-resistant coagulase-positive staphylococci (MRCoPS) among veterinary staff, hand-touch sites and surgical tissue during cystotomy operations on cats and dogs that were patients, and to analyze the genetic relatedness and antimicrobial resistance profiles of the isolates. Human and environmental samples were obtained from the nasal passageways of 12 surgeons and veterinary assistants and from 29 hand-touch sites of instruments in operative units and subjected to bacterial isolation and enumeration. Swab samples were collected in triplicate from 29 dogs and three cats at the site of incision, from the incision area, from the peritoneum during surgery and from the peritoneum before suture. MRCoPS were identified by mecA gene detection and characterized by their antibiogram profile, SCCmec type and pulsed-field gel electrophoresis. Twenty-four staphylococci were isolated, derived from one veterinary assistant, 12 operating room floor areas and hand-touch sites, three dogs and one cat. Methicillin-resistant S. pseudintermedius (MRSP) was found on an electric clipper and rebreathing circuits in the operating room. Three dogs were positive for MRSP during surgery, and one methicillin-resistant S. aureus (MRSA) was detected in a cat. All MRCoPS were resistant to doxycycline, erythromycin, clindamycin and enrofloxacin, but no patients developed surgical site infections. According to their genotypic patterns, the clones obtained from the environment and human sources differed from the animal clones. Despite intensive hygienic management, a variety of MRCoPS clones were present within the surgical unit and during surgery.

Development and validation of the Child Oral Health Impact Profile - Preschool version.

PubMed

Ruff, R R; Sischo, L; Chinn, C H; Broder, H L

2017-09-01

The Child Oral Health Impact Profile (COHIP) is a validated instrument created to measure the oral health-related quality of life of school-aged children. The purpose of this study was to develop and validate a preschool version of the COHIP (COHIP-PS) for children aged 2-5. The COHIP-PS was developed and validated using a multi-stage process consisting of item selection, face validity testing, item impact testing, reliability and validity testing, and factor analysis. A cross-sectional convenience sample of caregivers having children 2-5 years old from four groups completed item clarity and impact forms. Groups were recruited from pediatric health clinics or preschools/daycare centers, speech clinics, dental clinics, or cleft/craniofacial centers. Participants had a variety of oral health-related conditions, including caries, congenital orofacial anomalies, and speech/language deficiencies such as articulation and language disorders. COHIP-PS. The COHIP-PS was found to have acceptable internal validity (a = 0.71) and high test-retest reliability (0.87), though internal validity was below the accepted threshold for the community sample. While discriminant validity results indicated significant differences across study groups, the overall magnitude of differences was modest. Results from confirmatory factor analyses support the use of a four-factor model consisting of 11 items across oral health, functional well-being, social-emotional well-being, and self-image domains. Quality of life is an integral factor in understanding and assessing children's well-being. The COHIP-PS is a validated oral health-related quality of life measure for preschool children with cleft or other oral conditions. Copyright© 2017 Dennis Barber Ltd.

Effect of different packaging methods and storage temperature on microbiological and physicochemical quality characteristics of meatball.

PubMed

Yilmaz, I; Demirci, M

2010-06-01

The objective of this research was to determine physicochemical changes and microbiological quality of the different packaged meatball samples. Meatball samples in polystyrene tray were closed with polyethylene film (PS packs), vacuumed and modified atmosphere packaged, (MAP) (65% N(2), 35% CO(2)), and held under refrigerated display (4 °C) for 8, 16 and 16 days for PS packs, vacuum and MAP, respectively. Microbial load, free fatty acids and thiobarbituric acid values of the samples tended to increase with storage time. Bacteria counts of the raw meatball samples increased 2 log cycles at the end of storage compared with initial values. Meatball samples can be stored without any microbiological problem for 7 days at 4 °C. Results from this study suggested that shelf-life assigned to modified-MAP and vacuum-packed meatballs may be appropriate. Meatball samples underwent physical deformation when they were packed before vacuum process. With these negative factors considered, MAP is superior to other two packs methods.

Paper spray mass spectrometry and chemometric tools for a fast and reliable identification of counterfeit blended Scottish whiskies.

PubMed

Teodoro, Janaína Aparecida Reis; Pereira, Hebert Vinicius; Sena, Marcelo Martins; Piccin, Evandro; Zacca, Jorge Jardim; Augusti, Rodinei

2017-12-15

A direct method based on the application of paper spray mass spectrometry (PS-MS) combined with a chemometric supervised method (partial least square discriminant analysis, PLS-DA) was developed and applied to the discrimination of authentic and counterfeit samples of blended Scottish whiskies. The developed methodology employed the negative ion mode MS, included 44 authentic whiskies from diverse brands and batches and 44 counterfeit samples of the same brands seized during operations of the Brazilian Federal Police, totalizing 88 samples. An exploratory principal component analysis (PCA) model showed a reasonable discrimination of the counterfeit whiskies in PC2. In spite of the samples heterogeneity, a robust, reliable and accurate PLS-DA model was generated and validated, which was able to correctly classify the samples with nearly 100% success rate. The use of PS-MS also allowed the identification of the main marker compounds associated with each type of sample analyzed: authentic or counterfeit. Copyright © 2017 Elsevier Ltd. All rights reserved.

Clinical efficacy and pharmacokinetics of meloxicam in Mediterranean buffalo calves (Bubalus bubalis)

PubMed Central

Cagnardi, Petra; Villa, Roberto; D’Andrea, Luigi; Di Loria, Antonio; Ferrante, Maria Carmela; Borriello, Giuliano; Zicarelli, Luigi; Ciaramella, Paolo

2017-01-01

The aims of the investigation were to establish for the first time (i) clinical efficacy and (ii) pharmacokinetic profile of meloxicam intravenously (IV) administered in male Mediterranean buffalo calves after surgical orchiectomy. The study was performed on 10 healthy buffalo calves, between 4 and 5 months old and between 127 and 135 kg of body weight (b.w.). An IV injection of 0.5 mg/kg b.w. of meloxicam was administered in six calves (treated group, TG) immediately after surgery; the other four animals were used as untreated control group (CG). The clinical efficacy of meloxicam was evaluated pre- and post-surgery by monitoring respiratory rate (RR), heart rate (HR), rectal temperature (T°C), serum cortisol levels (SCL) and pain score (PS). Significant inter-groups differences were detected at sampling times (T): 4 hour (h) for RR (P<0.05), at T1-4-6-8 h for PS (P<0.05) and at T4-6-8 h for SCL (P < 0.0001). Regarding the mean intra-group values observed pre (T0) and post-surgery (from T15 min to T72 h), significant difference between the groups were found for RR (P<0.01), PS and SCL (P<0.05). The pharmacokinetic profile was best fitted by a two-compartmental model and characterized by a fast distribution half-life and slow elimination half-life (0.09 ± 0.06 h and 21.51 ± 6.4 h, respectively) and meloxicam mean concentrations at 96 h was of 0.18 ± 0.14 μg/mL. The volume of distribution and clearance values were quite low, but reasonably homogenous among individuals (Vdss 142.31 ± 55.08 mL/kg and ClB 4.38 ± 0.95 mL/kg/h, respectively). The IV administration of meloxicam in buffalo calves shows encouraging effects represented by significant and prolonged analgesic effects, significant reduction of SCL as well as similar pharmacokinetic profile to bovine calves. PMID:29077759

Polarization-sensitive optical coherence tomography using continuous polarization modulation with arbitrary phase modulation amplitude

NASA Astrophysics Data System (ADS)

Lu, Zenghai; Kasaragod, Deepa K.; Matcher, Stephen J.

2012-03-01

We demonstrate theoretically and experimentally that the phase retardance and relative optic-axis orientation of a sample can be calculated without prior knowledge of the actual value of the phase modulation amplitude when using a polarization-sensitive optical coherence tomography system based on continuous polarization modulation (CPM-PS-OCT). We also demonstrate that the sample Jones matrix can be calculated at any values of the phase modulation amplitude in a reasonable range depending on the system effective signal-to-noise ratio. This has fundamental importance for the development of clinical systems by simplifying the polarization modulator drive instrumentation and eliminating its calibration procedure. This was validated on measurements of a three-quarter waveplate and an equine tendon sample by a fiber-based swept-source CPM-PS-OCT system.

Correlates of protection for enteric vaccines.

PubMed

Holmgren, Jan; Parashar, Umesh D; Plotkin, Stanley; Louis, Jacques; Ng, Su-Peing; Desauziers, Eric; Picot, Valentina; Saadatian-Elahi, Mitra

2017-06-08

An immunological Correlate of Protection (CoP) is an immune response that is statistically interrelated with protection. Identification of CoPs for enteric vaccines would help design studies to improve vaccine performance of licensed vaccines in low income settings, and would facilitate the testing of future vaccines in development that might be more affordable. CoPs are lacking today for most existing and investigational enteric vaccines. In order to share the latest information on CoPs for enteric vaccines and to discuss novel approaches to correlate mucosal immune responses in humans with protection, the Foundation Mérieux organized an international conference of experts where potential CoPs for vaccines were examined using case-studies for both bacterial and viral enteric pathogens. Experts on the panel concluded that to date, all established enteric vaccine CoPs, such as those for hepatitis A, Vi typhoid and poliovirus vaccines, are based on serological immune responses even though these may poorly reflect the relevant gut immune responses or predict protective efficacy. Known CoPs for cholera, norovirus and rotavirus could be considered as acceptable for comparisons of similarly composed vaccines while more work is still needed to establish CoPs for the remaining enteric pathogens and their candidate vaccines. Novel approaches to correlate human mucosal immune responses with protection include the investigation of gut-originating antibody-secreting cells (ASCs), B memory cells and follicular helper T cells from samples of peripheral blood during their recirculation. Copyright © 2017.

A systematic review of clinical outcomes in surgical treatment of adult isthmic spondylolisthesis.

PubMed

Noorian, Shaya; Sorensen, Karen; Cho, Woojin

2018-05-07

A variety of surgical methods are available for the treatment of adult isthmic spondylolisthesis, but there is no consensus regarding their relative effects on clinical outcomes. To compare the effects of different surgical techniques on clinical outcomes in adult isthmic spondylolisthesis. Systematic Review PATIENT SAMPLE: A total of 1,538 patients from six randomized clinical trials and nine observational studies comparing different surgical treatments in adult isthmic spondylolisthesis. Primary outcome measures of interest included differences in pre- versus post-surgical assessments of pain, functional disability, and overall health as assessed by validated pain rating scales and questionnaires. Secondary outcome measures of interest included intraoperative blood loss, length of hospital stay, surgery duration, reoperation rates, and complication rates. A search of the literature was performed in September, 2017 for relevant comparative studies published in the prior 10-year period in the following databases: PubMed, Embase, Web of Science, and ClinicalTrials.Gov. PRISMA guidelines were followed and studies were included/excluded based on strict predetermined criteria. Quality appraisal was conducted using the Newcastle-Ottawa Scale (NOS) for observational studies and the Cochrane Collaboration's risk of bias assessment tool for randomized clinical trials. The authors received no funding support to conduct this review. A total of 15 studies (6 randomized clinical trials and 9 observational studies) were included for full text review, a majority of which only included cases of low-grade isthmic spondylolisthesis. 1 study examined the effects of adding pedicle screw fixation (PS) to posterolateral fusion (PLF) and 2 studies examined the effects of adding reduction to interbody fusion (IF) + PS on clinical outcomes. 5 studies compared PLF, 4 with and 1 without PS, to IF + PS. Additionally, 3 studies compared circumferential fusion (IF + PS + PLF) to IF + PS and 1 study compared circumferential fusion to PLF + PS. 3 studies compared clinical outcomes among different IF + PS techniques (ALIF + PS vs. PLIF + PS vs TLIF + PS) without PLF. As per the Cochrane Collaboration's risk of bias assessment tool, 4 randomized clinical trials had an overall low risk of bias, 1 randomized clinical trial had an unclear risk of bias, and 1 randomized clinical trial had a high risk of bias. As per the Newcastle-Ottawa scale, 3 observational studies were of overall good quality, 4 observational studies were of fair quality, and 2 observational studies were of poor quality. Available studies provide strong evidence that the addition of reduction to fusion does not result in better clinical outcomes of pain and function in low-grade isthmic spondylolisthesis. Evidence also suggests that there is no significant difference between interbody fusion (IF + PS) and posterior fusion (PLF +/- PS) in outcomes of pain, function, and complication rates at follow-up points up to approximately 3 years in cases of low-grade slips. However, studies with longer follow-up points suggest that interbody fusion (IF + PS) may perform better in these same measures at later follow-up points. Available evidence also suggests no difference between circumferential fusion (IF + PS + PLF) and interbody fusion (IF + PS) in outcomes of pain and function in low-grade slips, but circumferential fusion has been associated with greater intraoperative blood loss, longer surgery duration, and longer hospital stays. In terms of clinical outcomes, insufficient evidence is available to assess the utility of adding PS to PLF, the relative efficacy of different interbody fusion (IF + PS) techniques (ALIF + PS vs. TLIF + PS vs. PLIF + PS), and the relative efficacy of circumferential fusion and posterior fusion (PLF + PS). Copyright © 2018. Published by Elsevier Inc.

A unique mid-sequence linker used to multimerize the lipid-phosphatidylserine (PS) binding peptide-peptoid hybrid PPS1.

PubMed

Shukla, Satya Prakash; Manarang, Joseph C; Udugamasooriya, D Gomika

2017-09-08

Ligand multimerizations enhance the binding affinity towards cell surface biomarkers through their avidity effects. Typical linkers connect individual monomeric ligand moieties from one end (e.g., C- or N-terminus of a peptide) and exclusively target protein receptors. The lipid phosphatidylserine (PS) is normally present on the cytoplasmic side of the eukaryotic cell membrane, but in tumors and tumor endothelial cells, this negatively charged PS flips to the outer layer. We recently reported a PS binding peptide-peptoid hybrid (PPS1) that has distinct positively charged and hydrophobic residue-containing regions. The PPS1 monomer is inactive, and upon C-terminal dimerization (PPS1D1), it triggers cytotoxicity. In the current study, a unique series of PPS1 multimeric derivatives were synthesized by switching the linker from the C-terminus to an internal position. The unimportant fourth residue (N-lys) from the C-terminus was utilized to build the linker. The synthesis strategy was developed employing variations of (I) the linker size, (II) the number of positively charged residues, and (III) the number of hydrophobic regions. Cytotoxicity of these new derivatives on HCC4017 lung cancer cells showed that a minimum of two hydrophobic regions was important to retain the activity and that the shortest linker length was optimal for activity. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

In vivo imaging of brain infarct with the novel fluorescent probe PSVue 794 in a rat middle cerebral artery occlusion-reperfusion model.

PubMed

Chu, Chun; Huang, Xiaofang; Chen, Chiung-Tong; Zhao, Yuanli; Luo, Jin J; Gray, Brian D; Pak, Koon Y; Dun, Nae J

2013-01-01

The utility of PSVue 794 (PS794), a near-infrared fluorescent dye conjugated to a bis[zinc (II)-dipicolylamine] (Zn-DPA) targeting moiety, in imaging brain infarct was assessed in a rat middle cerebral artery occlusion-reperfusion model. Following reperfusion, 1 mM PS794 solution was administered intravenously via a tail vein. Fluorescence images were captured between 6 to 72 hours postinjection using a LI-COR Biosciences Pearl Imaging System. Strong fluorescence signals, which may represent the infarct core, were detected in the right hemisphere, ipsilateral to the injured site, and weaker signals in areas surrounding the core. In ischemia-reperfusion rats injected with a control dye not linked to a targeting agent, fluorescence was distributed diffusely throughout the brain. To address the issue of whether Zn-DPA targets apoptotic/necrotic cells, HT22 mouse hippocampal neurons were cultured in either Dulbecco's Modified Eagle's Medium, serum-deprived medium, Hank's Balanced Salt Solution, or L-glutamate (10 mM)-containing medium for up to 33 hours. Cells were then double-labeled with PSVue 480 (Zn-DPA conjugated to fluorescein isothiocyanate) and propidium iodide, which labels necrotic cells. Microscopic examination revealed that PS480 targeted apoptotic and necrotic cells. The result indicates that PS794 is applicable to in vivo imaging of brain infarct and that Zn-DPA selectively targets apoptotic/necrotic cells.

Methane in the South China Sea and the Western Philippine Sea

NASA Astrophysics Data System (ADS)

Tseng, Hsiao-Chun; Chen, Chen-Tung Arthur; Borges, Alberto V.; DelValls, T. Angel; Chang, Yu-Chang

2017-03-01

Approximately 700 water samples from the South China Sea (SCS) and 300 water samples from the western Philippine Sea (wPS) were collected during eight cruises from August 2003 to July 2007 to determine methane (CH4) distributions from the surface to a depth of 4250 m. The surface CH4 concentrations exceeded atmospheric equilibrium, both in the SCS and the wPS, and the concentrations were 4.5±3.6 and 3.0±1.2 nmol L-1, respectively. The sea-to-air fluxes were calculated, and the SCS and the wPS were found to emit CH4 to the atmosphere at 8.6±6.4 μmol m-2 d-1 and 4.9±4.9 μmol m-2 d-1, respectively. In the SCS, CH4 emissions were higher over the continental shelf (11.0±7.4 μmol m-2 d-1) than over the deep ocean (6.1±6.0 μmol m-2 d-1), owing to greater biological productivity and closer coupling with the sediments on the continental shelf. The SCS emitted 30.1×106 mol d-1 CH4 to the atmosphere and exported 1.82×106 mol d-1 CH4 to the wPS. The concentrations of both CH4 and chlorophyll a were high in the 150 m surface layer of the wPS, but were not significantly correlated with each other. CH4 concentrations generally declined with increasing depth below the euphotic zone but remained constant below 1,000 m, both in the SCS and the wPS. Some high CH4 concentrations were observed at mid-depths and bottom waters in the SCS, and were most likely caused by the release of CH4 from gas hydrates or gas seepage.

IgM antibodies to oxidized phosphatidylserine as protection markers in cardiovascular disease among 60-year olds

PubMed Central

Frostegård, Johan; Su, Jun; Sing, Sudhir; Hua, Xiang; Vikström, Max; Leander, Karin; Gigante, Bruna; de Faire, Ulf; Frostegård, Anna G.

2017-01-01

Objective Phosphatidylserine is exposed on apoptotic cells and is prone to oxidation (OxPS). Here we analyze the association of IgM antibodies against OxPS (anti-OxPS) with the risk of cardiovascular disease (CVD). Methods Among sixty-year olds from Stockholm County in Sweden, previously screened for cardiovascular risk factors (2039 men, 2193 women), there were 210 incident CVD-cases identified during a 5-year follow-up. Using a nested case-control design, 622 age- and sex-matched controls were selected. Odds ratios (OR) with 95% intervals (CI) were calculated by conditional logistic regression. IgM anti-OxPS was measured by ELISA. Phagocytosis of apoptotic Jurkat-cells by macrophages was studied by flow cytometry. Results Anti-OxPS levels were lower among cases (median (interquartile range): 80.7 (60.9–101.0 vs. 84.6 (65.8–109.6); p = 0.047); among men (76.6 (55.8–99.2) vs. 82.0 (63.1–105.1); p = 0.022) and among women 89.6 (72.3–110.1) vs. 89.8 (69.9–114.4); p = 0.79). After adjustment for smoking, BMI, diabetes mellitus type II, hypercholesterolaemia and hypertension, and dividing into quartiles, using the highest quartile (quartile 4) as reference, quartile 3 was associated with a OR of 1.74 (CI 1.08–2.81). Quartiles 2 and 1 had similar associations, the later reaching statistical significance. Among men associations were stronger whereas no significant associations were observed in women. The OR of MI/angina comparing quartile 3 with quartile 4 was 2.31 (CI 1.30–4.11). The OR for quartile 2 and 1, respectively, were similar as for quartile 3. Total IgM increased uptake of apoptotic cells, which was reversed if incubated with OxPS. Conclusions IgM anti-OxPS is a novel potential protection marker for CVD, in particular in men. Increased phagocytosis of dying/dead cells could be one potential underlying mechanism. PMID:28430795

Use of transcriptomic data for extending a model of the AppA/PpsR system in Rhodobacter sphaeroides.

PubMed

Pandey, Rakesh; Armitage, Judith P; Wadhams, George H

2017-12-28

Photosynthetic (PS) gene expression in Rhodobacter sphaeroides is regulated in response to changes in light and redox conditions mainly by PrrB/A, FnrL and AppA/PpsR systems. The PrrB/A and FnrL systems activate the expression of them under anaerobic conditions while the AppA/PpsR system represses them under aerobic conditions. Recently, two mathematical models have been developed for the AppA/PpsR system and demonstrated how the interaction between AppA and PpsR could lead to a phenotype in which PS genes are repressed under semi-aerobic conditions. These models have also predicted that the transition from aerobic to anaerobic growth mode could occur via a bistable regime. However, they lack experimentally quantifiable inputs and outputs. Here, we extend one of them to include such quantities and combine all relevant micro-array data publically available for a PS gene of this bacterium and use that to parameterise the model. In addition, we hypothesise that the AppA/PpsR system alone might account for the observed trend of PS gene expression under semi-aerobic conditions. Our extended model of the AppA/PpsR system includes the biological input of atmospheric oxygen concentration and an output of photosynthetic gene expression. Following our hypothesis that the AppA/PpsR system alone is sufficient to describe the overall trend of PS gene expression we parameterise the model and suggest that the rate of AppA reduction in vivo should be faster than its oxidation. Also, we show that despite both the reduced and oxidised forms of PpsR binding to the PS gene promoters in vitro, binding of the oxidised form as a repressor alone is sufficient to reproduce the observed PS gene expression pattern. Finally, the combination of model parameters which fit the biological data well are broadly consistent with those which were previously determined to be required for the system to show (i) the repression of PS genes under semi-aerobic conditions, and (ii) bistability. We found that despite at least three pathways being involved in the regulation of photosynthetic genes, the AppA/PpsR system alone is capable of accounting for the observed trends in photosynthetic gene expression seen at different oxygen levels.

Mass test of AdvanSiD model ASD-NUV3S-P SiliconPMs for the Pixel Timing Counter of the MEG II experiment

NASA Astrophysics Data System (ADS)

Rossella, M.; Bariani, S.; Barnaba, O.; Cattaneo, P. W.; Cervi, T.; Menegolli, A.; Nardò, R.; Prata, M. C.; Romano, E.; Scagliotti, C.; Simonetta, M.; Vercellati, F.

2017-02-01

The MEG II Timing Counter will measure the positron time of arrival with a resolution of 30 ps relying on two arrays of scintillator pixels read out by 6144 Silicon Photomultipliers (SiPMs) from AdvanSiD. They must be characterized, measuring their breakdown voltage, to assure that the gains of the SiPMs of each pixel are as uniform as possible, to maximize the pixel resolution. To do this an automatic test system that can measure sequentially the parameters of 32 devices has been developed.

Identification of polymer stabilized blue-phase liquid crystal display by chromaticity diagram

NASA Astrophysics Data System (ADS)

Lan, Yi-Fen; Tsai, Cheng-Yeh; Wang, Ling-Yung; Ku, Po-Jen; Huang, Tai-Hsiang; Liu, Chu-Yu; Sugiura, Norio

2012-04-01

We reported an identification method of blue phase liquid crystal (BPLC) display status by using Commission International de l'Éclairage (CIE) chromaticity diagram. The BPLC was injected into in-plane-switch (IPS) cell, polymer stabilized (PS) by ultraviolet cured process and analyzed by luminance colorimeter. The results of CIE chromaticity diagram showed a remarkable turning point when polymer stabilized blue phase liquid crystal II (PSBPLC-II) formed in the IPS cell. A mechanism of CIE chromaticity diagram identify PSBPLC display status was proposed, and we believe this finding will be useful to application and production of PSBPLC display.

Microcontact printing of BMP-2 and its effect on human chondrocytes behavior

NASA Astrophysics Data System (ADS)

Pan, Chang-Jiang; Nie, Yu-Dong

2010-01-01

The present study is to investigate human chondrocytes behavior on microcontact printed bone morphogenetic protein-2 (BMP-2) lines on polystyrene (PS) surface. It was found that the cells aligned with BMP lines and expressed type II and VI collagen. The chondrocytes in vitro cultured on BMP lines were elongated, which resulted in altered cell morphology. Taking all these results into consideration, BMP-2 lines enhance cell adhesion, restrict spreading, and increase type II and VI collagen expression. The results represented in this study may be an approach to the problem of engineering reparative cartilage in vitro.

Agreement between patients' self-report and medical records for vaccination: the PGRx database.

PubMed

Grimaldi-Bensouda, Lamiae; Aubrun, Elodie; Leighton, Pamela; Benichou, Jacques; Rossignol, Michel; Abenhaim, Lucien

2013-03-01

Patients' self-reported vaccine exposure (PS) may be subject to memory errors and other biases. Physicians' prescription records and other medical records (MR) do not capture noncompliance with vaccination. This study compared PS with MR for influenza, 23-valent pneumococcal, and human papillomavirus (HPV) vaccines. The Pharmacoepidemiologic General Research Extension (PGRx) database uses a network of over 300 general practitioners across France, who systematically recruit an age- and sex-stratified sample of patients (≥ 14 years old), without reference to their diagnoses or prescriptions. Patients received a structured telephone interview, combined with an interview guide listing vaccines commonly given. Patients' self-reported vaccination in the 3 years before their recruitment was compared with medical records kept by the physician or the patient. Concordance between PS and MR was assessed for 7613 patients for whom both sources of information were available. Agreement within 3 years before the recruitment date was substantial for influenza vaccines (prevalence and bias-adjusted kappa [PABAK] = 0.74, sensitivity PS relative to MR 81.5%) and high for 23-valent pneumococcal vaccines (PABAK = 0.98, sensitivity PS 49.6) and HPV vaccines (PABAK = 0.92, sensitivity PS 91.6). In adjusted analyses, agreement varied with sociodemographic and health-related factors, particularly for influenza and 23-valent pneumococcal vaccines. The PGRx method for drug exposure assessment is a new tool in pharmacoepidemiology that shows substantial to high agreement between PS and MR for exposure to various vaccines. Our finding of high agreement between PS and MR for HPV vaccination status in young women is a significant addition to the literature. Copyright © 2013 John Wiley & Sons, Ltd.

Independence From Parenteral Nutrition and Intravenous Fluid Support During Treatment With Teduglutide Among Patients With Intestinal Failure Associated With Short Bowel Syndrome

PubMed Central

Iyer, Kishore R.; Kunecki, Marek; Boullata, Joseph I.; Fujioka, Ken; Joly, Francisca; Gabe, Simon; Pape, Ulrich-Frank; Schneider, Stéphane M.; Virgili Casas, María Nuria; Ziegler, Thomas R.; Li, Benjamin; Youssef, Nader N.; Jeppesen, Palle B.

2016-01-01

Background: In phase III clinical studies, treatment with teduglutide was associated with clinically meaningful reductions (≥20% from baseline) in parenteral support (PS; parenteral nutrition and/or intravenous fluids) requirements in adult patients with intestinal failure associated with short bowel syndrome (SBS-IF). This analysis reports clinical characteristics of patients who achieved complete independence from PS during teduglutide treatment. Materials and Methods: Post hoc analysis of adult patients who achieved complete PS independence during treatment with teduglutide 0.05 mg/kg/d. Data were pooled from 5 teduglutide clinical trials (2 phase III placebo-controlled trials [NCT00081458 and NCT00798967] and their respective extension studies [NCT00172185, NCT00930644, NCT01560403]). Descriptive statistics were used; no between-group comparisons were performed because of the small sample size and lack of comparator. Results: Of 134 patients, 16 gained oral or enteral autonomy after a median of 5 years of PS dependence and 89 weeks of teduglutide treatment. Demographic and baseline disease characteristics varied among patients (median age, 55 years; 50% men; median baseline PS volume, 5.1 L/wk; median residual small intestine length, 52.5 cm). Most patients who achieved PS independence had colon-in-continuity; however, there was no significant difference in the frequency of PS independence among patients who maintained colon-in-continuity vs those who did not. Conclusion: Findings from this post hoc analysis suggest that oral or enteral autonomy is possible for some patients with SBS-IF who are treated with teduglutide, regardless of baseline characteristics and despite long-term PS dependence. PMID:27875291

Correlation between polarization sensitive optical coherence tomography and SHG microscopy in articular cartilage

NASA Astrophysics Data System (ADS)

Zhou, Xin; Ju, Myeong Jin; Huang, Lin; Tang, Shuo

2017-02-01

Polarization-sensitive optical coherence tomography (PS-OCT) and second harmonic generation (SHG) microscopy are two imaging modalities with different resolutions, field-of-views (FOV), and contrasts, while they both have the capability of imaging collagen fibers in biological tissues. PS-OCT can measure the tissue birefringence which is induced by highly organized fibers while SHG can image the collagen fiber organization with high resolution. Articular cartilage, with abundant structural collagen fibers, is a suitable sample to study the correlation between PS-OCT and SHG microscopy. Qualitative conjecture has been made that the phase retardation measured by PS-OCT is affected by the relationship between the collagen fiber orientation and the illumination direction. Anatomical studies show that the multilayered architecture of articular cartilage can be divided into four zones from its natural surface to the subchondral bone: the superficial zone, the middle zone, the deep zone, and the calcified zone. The different zones have different collagen fiber orientations, which can be studied by the different slopes in the cumulative phase retardation in PS-OCT. An algorithm is developed based on the quantitative analysis of PS-OCT phase retardation images to analyze the microstructural features in swine articular cartilage tissues. This algorithm utilizes the depth-dependent slope changing of phase retardation A-lines to segment structural layers. The results show good consistency with the knowledge of cartilage morphology and correlation with the SHG images measured at selected depth locations. The correlation between PS-OCT and SHG microscopy shows that PS-OCT has the potential to analyze both the macro and micro characteristics of biological tissues with abundant collagen fibers and other materials that may cause birefringence.

Analysis of Bs flavor oscillations at CDF

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

Guerreiro Leonardo, Nuno Teotonio Viegas

2006-09-01

The search for and study of flavor oscillations in the neutral B sB s meson system is an experimentally challenging task. It constitutes a flagship analysis of the Tevatron physics program. In this dissertation, they develop an analysis of the time-dependent B s flavor oscillations using data collected with the CDF detector. The data samples are formed of both fully and partially reconstructed B meson decays: B s → D sπ(ππ) and B s → D slv. A likelihood fitting framework is implemented and appropriate models and techniques developed for describing the mass, proper decay time, and flavor tagging characteristicsmore » of the data samples. The analysis is extended to samples of B + and B 0 mesons, which are further used for algorithm calibration and method validation. The B mesons lifetimes are extracted. The measurement of the B 0 oscillation frequency yields Δm d = 0.522 ± 0.017 ps -1. The search for B s oscillations is performed using an amplitude method based on a frequency scanning procedure. Applying a combination of lepton and jet charge flavor tagging algorithms, with a total tagging power ϵ'D 2 of 1.6%, to a data sample of 355 pb -1, a sensitivity of 13.0 ps -1 is achieved. They develop a preliminary same side kaon tagging algorithm, which is found to provide a superior tagging power of about 4.0% for the B s meson species. A study of the dilution systematic uncertainties is not reported. From its application as is to the B s samples the sensitivity is significantly increased to about 18 ps -1 and a hint of a signal is seen at about 175. ps -1. They demonstrate that the extension of the analysis to the increasing data samples with the inclusion of the same side tagging algorithm is capable of providing an observation of B s mixing beyond the standard model expectation. They show also that the improved knowledge of Δm s has a considerable impact on constraining the CKM matrix elements.« less

A theoretical model for the Gla-TSR-EGF-1 region of the anticoagulant cofactor protein S: From biostructural pathology to specie

NASA Astrophysics Data System (ADS)

Villoutreix, Bruno O.; Teleman, Olle; Dahlbäck, Björn

1997-05-01

Protein S (PS), which functions as a species-specific anticoagulant cofactor to activated protein C (APC), is a mosaic protein that interacts with the phospholipid membrane via its γ-carboxyglutamate-rich (Gla) module. This module is followed by the thrombin-sensitive region (TSR), sensitive to thrombin cleavage, four epidermal growth factor (EGF)-like modules and a last region referred to as the sex hormone binding globulin (SHBG) domain. Of these, the TSR and the first EGF-like regions have been shown to be important for the species-specific interaction with APC. Difficulties in crystallising PS have so far hindered its study at the atomic level. Here, we report theoretical models for the Gla and EGF-1 modules of human PS constructed using prothrombin and factor X experimental structures. The TSR was built interactively. Analysis of the model linked with the large body of biochemical literature on PS and related proteins leads to suggestions that (i) the TSR stabilises the calcium-loaded Gla module through hydrophobic and ionic interactions and its conformation depends on the presence of the Gla module; (ii) the TSR does not form a calcium binding site but is protected from thrombin cleavage in the calcium-loaded form owing to short secondary structure elements and close contact with the Gla module; (iii) the PS missense mutations in this region are consistent with the structural data, except in one case which needs further investigation; and (iv) the two PS `faces' involving regions of residues Arg49-Gln52-Lys97 (TSR-EGF-1) and Thr103-Pro106 (EGF-1) may be involved in species-specific interactions with APC as they are richer in nonconservative substitution when comparing human and bovine protein S. This preliminary model helps to plan future experiments and the resulting data will be used to further validate and optimise the present structure.

Effect of methanolic extract of Piper sarmentosum leaves on neointimal foam cell infiltration in rabbits fed with high cholesterol diet

PubMed Central

Amran, Adel A.; Zakaria, Zaiton; Othman, Faizah; Das, Srijit; Al-Mekhlafi, Hesham M.; Raj, Santhana; Nordin, Nor-Anita MM

2012-01-01

Previous research has shown the beneficial effects of aqueous extract of Piper sarmentosum (P.s) on atherosclerosis. The first stage in atherosclerosis is the formation of foam cell. The aim of this study was to investigate the effect of the methanol extract of P.s on fatty streaks by calculating neointimal foam cell infiltration in rabbits fed with high cholesterol diet. Thirty six male New Zealand white rabbits were divided equally into six groups: (i) C: control group fed normal rabbit chow; (ii) CH: cholesterol diet (1 % cholesterol); (iii) PM1: 1 % cholesterol with methanol extract of P.s (62.5 mg/kg); (iv) PM2: 1 % cholesterol with methanol extract of P.s (125 mg/kg); (v) PM3: 1 % cholesterol with methanol extract of P.s (250 mg/kg); (vi) SMV group fed 1 % cholesterol supplemented with Simvistatin drug (1.2 mg/kg). All animals were treated for 10 weeks. At the end of the treatment, the rabbits were fasted and sacrificed and the aortic tissues were collected for histological studies to measure the area of the neointimal foam cell infiltration using software. The thickening of intima ratio of atherosclerosis and morphological changes by scanning electron microscope were measured. The results showed that the atherosclerotic group had significantly bigger area of fatty streak compared to the control group. The area of fatty streak in the abdominal aorta was significantly reduced in the treatment groups which were similar with the SMV group. Similarly, there was a reduction in the number of foam cell in the treatment groups compared to the atherosclerotic group as seen under scanning microscope. In conclusion, histological study demonstrated that the methanol extract of the P.s could reduce the neointimal foam cell infiltration in the lumen of the aorta and the atherosclerotic lesion. PMID:27366140

The Relationship between Patient Satisfaction with Service Quality and Survival in Non-Small Cell Lung Cancer - Is Self-Rated Health a Potential Confounder?

PubMed

Lis, Christopher G; Patel, Kamal; Gupta, Digant

2015-01-01

Previously we reported that higher patient satisfaction (PS) with service quality is associated with favorable survival outcomes in a variety of cancers. However, we cautioned the readers that patients with greater satisfaction might be the ones with better self-rated health (SRH), a well-established prognosticator of cancer survival. In other words, SRH could potentially confound the PS and survival relationship. We investigated this hypothesis in non-small cell lung cancer (NSCLC). 778 NSCLC patients (327 males and 451 females; mean age 58.8 years) treated at 4 Cancer Treatment Centers of America hospitals between July 2011 and March 2013. PS was measured on a 7-point scale ranging from "completely dissatisfied" to "completely satisfied". SRH was measured on a 7-point scale ranging from "very poor" to "excellent". Both were dichotomized into 2 categories: top box response (7) versus all others (1-6). Patient survival was the primary end point. Cox regression was used to evaluate the association between PS and survival controlling for covariates. 74, 70, 232 and 391 patients had stage I, II, III and IV disease respectively. 631 (81.1%) patients were "completely satisfied". 184 (23.7%) patients had "excellent" SRH. There was a weak but significant correlation between overall PS and SRH (Kendall's tau b = 0.19; p<0.001). On univariate analysis, "completely satisfied" patients had a significantly lower risk of mortality (HR = 0.75; 95% CI: 0.57 to 0.99; p = 0.04). Similarly, patients with "excellent" SRH had a significantly lower risk of mortality (HR = 0.61; 95% CI: 0.46 to 0.81; p = 0.001). On multivariate analysis controlling for stage at diagnosis, treatment history and gender, SRH was found to be a significant predictor of survival (HR = 0.67; 95% CI: 0.50 to 0.89; p = 0.007) while PS was not (HR = 0.86; 95% CI: 0.64 to 1.2; p = 0.32). Among the individual PS items, the only significant independent predictor of survival was "teams communicating with each other concerning your medical condition and treatment" (HR = 0.59; 95% CI: 0.36 to 0.94; p = 0.03). SRH appears to confound the PS-survival relationship in NSCLC. SRH should be used as a control/stratification variable in analyses involving PS as a predictor of clinical cancer outcomes.

Phase II Trial Of PS-341 (Bortezomib) In Patients With Previously Treated Advanced Urothelial Tract Transitional Cell Carcinoma

ClinicalTrials.gov

2013-06-04

Metastatic Transitional Cell Cancer of the Renal Pelvis and Ureter; Recurrent Bladder Cancer; Recurrent Transitional Cell Cancer of the Renal Pelvis and Ureter; Recurrent Urethral Cancer; Stage III Bladder Cancer; Stage III Urethral Cancer; Stage IV Bladder Cancer; Stage IV Urethral Cancer; Transitional Cell Carcinoma of the Bladder; Ureter Cancer

Bibliography of Soviet Laser Developments, Number 28, March - April 1977.

DTIC Science & Technology

1978-02-24

Dyes " a. Rhodamine 25. Makogon, M.M. and V.B. Sukhanov (0). Dye laser with a partially se- lective resonator. ZhPS, v.26, no.4, 1977, 622-625. b...medium. KE, no.4, 1977, 751-757. 105. Bel’tyugov, V.N., I.I. Sukhanov , and Yu.V. Troitskiy (0). Thermal dis- tortions in intraresonator optical

Research in the Child Psychiatric and Guidance Clinics: Supplementary Bibliography II (1972).

ERIC Educational Resources Information Center

Klein, Zanvel E.

This bibliography is the third in a series of compilations of research related to pre-adolescent problems commonly treated through outpatient mental health settings such as clinics and schools. The original document (ED 073 849) covered literature up to 1971, and the first supplement (PS 007 263) focused on research that appeared in 1971. This,…

Search for Bs0 oscillations using inclusive lepton events

NASA Astrophysics Data System (ADS)

ALEPH Collaboration; Barate, R.; et al.

1999-03-01

A search for Bs0 oscillations is performed using a sample of semileptonic b-hadron decays collected by the ALEPH experiment during 1991-95. Compared to previous inclusive lepton analyses, the proper time resolution and b-flavour mistag rate are significantly improved. Additional sensitivity to Bs0 mixing is obtained by identifying subsamples of events having a Bs0 purity which is higher than the average for the whole data sample. Unbinned maximum likelihood amplitude fits are performed to derive a lower limit of Δ m s > 9.5 ps-1 at the 95% confidence limit (95% CL). Combining with the ALEPH Ds--based analyses yields Δ m s > 9.6 ps-1 at 95% CL.

A comparison of LIDT behavior of metal-dielectric mirrors in ns and ps pulse regime at 1030 nm with regard to the coating technology

NASA Astrophysics Data System (ADS)

Škoda, Václav; Vanda, Jan; Uxa, Štěpán

2017-11-01

Several sets of mirror samples with multilayer system Ta2O5/SiO2 on silver metal layer were manufactured using either PVD or IAD coating technology. Both BK7 and fused silica substrates were used for preparation of samples. Laserinduced- damage-threshold (LIDT) of metal-dielectric mirrors was tested using a laser apparatus working at 1030 nm wavelength, in ns and ps pulse length domains in S-on-1 test mode. The measured damage threshold values at 45 deg angle of incidence and P-polarization were compared for different pulse length, substrate materials and coating technology.

DAQ application of PC oscilloscope for chaos fiber-optic fence system based on LabVIEW

NASA Astrophysics Data System (ADS)

Lu, Manman; Fang, Nian; Wang, Lutang; Huang, Zhaoming; Sun, Xiaofei

2011-12-01

In order to obtain simultaneously high sample rate and large buffer in data acquisition (DAQ) for a chaos fiber-optic fence system, we developed a double-channel high-speed DAQ application of a digital oscilloscope of PicoScope 5203 based on LabVIEW. We accomplished it by creating call library function (CLF) nodes to call the DAQ functions in the two dynamic link libraries (DLLs) of PS5000.dll and PS5000wrap.dll provided by Pico Technology Company. The maximum real-time sample rate of the DAQ application can reach 1GS/s. We can control the resolutions of the application at the sample time and data amplitudes by changing their units in the block diagram, and also control the start and end times of the sampling operations. The experimental results show that the application has enough high sample rate and large buffer to meet the demanding DAQ requirements of the chaos fiber-optic fence system.

Sample preparation combined with electroanalysis to improve simultaneous determination of antibiotics in animal derived food samples.

PubMed

da Silva, Wesley Pereira; de Oliveira, Luiz Henrique; Santos, André Luiz Dos; Ferreira, Valdir Souza; Trindade, Magno Aparecido Gonçalves

2018-06-01

A procedure based on liquid-liquid extraction (LLE) and phase separation using magnetically stirred salt-induced high-temperature liquid-liquid extraction (PS-MSSI-HT-LLE) was developed to extract and pre-concentrate ciprofloxacin (CIPRO) and enrofloxacin (ENRO) from animal food samples before electroanalysis. Firstly, simple LLE was used to extract the fluoroquinolones (FQs) from animal food samples, in which dilution was performed to reduce interference effects to below a tolerable threshold. Then, adapted PS-MSSI-HT-LLE protocols allowed re-extraction and further pre-concentration of target analytes in the diluted acid samples for simultaneous electrochemical quantification at low concentration levels. To improve the peak separation, in simultaneous detection, a baseline-corrected second-order derivative approach was processed. These approaches allowed quantification of target FQs from animal food samples spiked at levels of 0.80 to 2.00 µmol L -1 in chicken meat, with recovery values always higher than 80.5%, as well as in milk samples spiked at 4.00 µmol L -1 , with recovery values close to 70.0%. Copyright © 2018 Elsevier Ltd. All rights reserved.

Core-shell poly-methylmethacrylate nanoparticles as effective carriers of electrostatically loaded anionic porphyrin.

PubMed

Varchi, Greta; Benfenati, Valentina; Pistone, Assunta; Ballestri, Marco; Sotgiu, Giovanna; Guerrini, Andrea; Dambruoso, Paolo; Liscio, Andrea; Ventura, Barbara

2013-05-01

Among the medical applications of nanoparticles, their usage as photosensitizer (PS) carriers for photodynamic therapy (PDT) has attracted increasing attention. In the present study we explored the morphological and photophysical properties of core-shell PMMA nanoparticles (PMMA-NPs) electrostatically post-loaded with the synthetic, water soluble 5,10,15,20-tetrakis(4-sulphonatophenyl)-porphyrin (TPPS4). pH response and singlet oxygen analyses of differently loaded samples proved the high capability of the PMMA-NPs to shield the PS from the environment, while retaining the PS singlet oxygen production capability. Preliminary in vitro imaging and phototoxicity experiments on HepG2 cells demonstrated the efficacy of the system to trigger photoinduced cell death in the culture.

Tunable light emission by exciplex state formation between hybrid halide perovskite and core/shell quantum dots: Implications in advanced LEDs and photovoltaics.

PubMed

Sanchez, Rafael S; de la Fuente, Mauricio Solis; Suarez, Isaac; Muñoz-Matutano, Guillermo; Martinez-Pastor, Juan P; Mora-Sero, Ivan

2016-01-01

We report the first observation of exciplex state electroluminescence due to carrier injection between the hybrid lead halide perovskite (MAPbI3-xClx) and quantum dots (core/shell PbS/CdS). Single layers of perovskite (PS) and quantum dots (QDs) have been produced by solution processing methods, and their photoluminescent properties are compared to those of bilayer samples in both PS/QD and QD/PS configurations. Exciplex emission at lower energies than the band gap of both PS and QD has been detected. The exciplex emission wavelength of this mixed system can be simply tuned by controlling the QD size. Light-emitting diodes (LEDs) have been fabricated using those configurations, which provide light emission with considerably low turn-on potential. The "color" of the LED can also be tuned by controlling the applied bias. The presence of the exciplex state PS and QDs opens up a broad range of possibilities with important implications not only in tunable LEDs but also in the preparation of intermediate band gap photovoltaic devices with the potentiality of surpassing the Shockley-Queisser limit.

Tunable light emission by exciplex state formation between hybrid halide perovskite and core/shell quantum dots: Implications in advanced LEDs and photovoltaics

PubMed Central

Sanchez, Rafael S.; de la Fuente, Mauricio Solis; Suarez, Isaac; Muñoz-Matutano, Guillermo; Martinez-Pastor, Juan P.; Mora-Sero, Ivan

2016-01-01

We report the first observation of exciplex state electroluminescence due to carrier injection between the hybrid lead halide perovskite (MAPbI3–xClx) and quantum dots (core/shell PbS/CdS). Single layers of perovskite (PS) and quantum dots (QDs) have been produced by solution processing methods, and their photoluminescent properties are compared to those of bilayer samples in both PS/QD and QD/PS configurations. Exciplex emission at lower energies than the band gap of both PS and QD has been detected. The exciplex emission wavelength of this mixed system can be simply tuned by controlling the QD size. Light-emitting diodes (LEDs) have been fabricated using those configurations, which provide light emission with considerably low turn-on potential. The “color” of the LED can also be tuned by controlling the applied bias. The presence of the exciplex state PS and QDs opens up a broad range of possibilities with important implications not only in tunable LEDs but also in the preparation of intermediate band gap photovoltaic devices with the potentiality of surpassing the Shockley-Queisser limit. PMID:26844299

Psychometric characteristics of the Rivermead Behavioural Memory Test (RBMT) as an early detection instrument for dementia and mild cognitive impairment in Brazil.

PubMed

Yassuda, Mônica Sanches; Flaks, Mariana Kneese; Viola, Luciane Fátima; Pereira, Fernanda Speggiorin; Memória, Claudia Maia; Nunes, Paula Villela; Forlenza, Orestes Vicente

2010-09-01

The Rivermead Behavioural Memory Test (RBMT) assesses everyday memory by means of tasks which mimic daily challenges. The objective was to examine the validity of the Brazilian version of the RBMT to detect cognitive decline. 195 older adults were diagnosed as normal controls (NC) or with mild cognitive impairment (MCI) or Alzheimer's disease (AD) by a multidisciplinary team, after participants completed clinical and neuropsychological protocols. Cronbach's alpha was high for the total sample for the RBMT profile (PS) and screening scores (SS) (PS = 0.91, SS = 0.87) and for the AD group (PS = 0.84, SS = 0.85), and moderate for the MCI (PS = 0.62, SS = 0.55) and NC (PS = 0.62, SS = 0.60) groups. RBMT total scores, Appointment, Pictures, Immediate and Delayed Story, Immediate and Delayed Route, Delayed Message and Date contributed to differentiate NC from MCI. ROC curve analyses indicated high accuracy to differentiate NC from AD patients, and, moderate accuracy to differentiate NC from MCI. The Brazilian version of the RBMT seems to be an appropriate instrument to identify memory decline in Brazilian older adults.

Effects of a community-based approach of food and psychosocial stimulation on growth and development of severely malnourished children in Bangladesh: a randomised trial.

PubMed

Nahar, B; Hossain, M I; Hamadani, J D; Ahmed, T; Huda, S N; Grantham-McGregor, S M; Persson, L A

2012-06-01

Psychosocial stimulation (PS) and food supplementation (FS) improve development of malnourished children. This study evaluates the effects of a community-based approach of PS and FS on growth and development of severely malnourished children. Severely underweight hospitalised children aged 6-24 months (n = 507) were randomly allocated on discharge to five groups: (i) PS, (ii) FS, (iii) PS+FS, (iv) clinic-control and (v) hospital-control. PS included play sessions and parental counselling on child development. This was done at each fortnightly follow-up visit, that is, every second week, for 6 months at community clinics. FS included distribution of cereal-based food packets (150-300 kcal/day) for 3 months. All groups received medical care, micronutrient supplementation, health-education and growth monitoring. Children's development was assessed using revised version of Bayley Scales of Infant Development at baseline and after 3 and 6 months of intervention. Anthropometry was measured using standard procedure. Comparing groups with any stimulation with those with no stimulation there was a significant effect of stimulation on children's mental development index (group*session interaction P = 0.037, effect size = 0.37 s.d.) and weight-for-age Z-score (group*session interaction P = 0.02, effect size=0.26 s.d.). Poor levels of development and nutritional status were sustained, however, due to their initial very severe malnutrition. There was no effect on motor development and linear growth. Children receiving any stimulation showed a significant benefit to mental development and growth in weight. More intensive intervention with longer duration is needed to correct their poor developmental levels and nutritional status.

Generation of hepatocyte-like cells from human induced pluripotent stem (iPS) cells by co-culturing embryoid body cells with liver non-parenchymal cell line TWNT-1.

PubMed

Javed, M Shahid; Yaqoob, Naeem; Iwamuro, Masaya; Kobayashi, Naoya; Fujiwara, Toshiyoshi

2014-02-01

To generate a homogeneous population of patient-specific hepatocyte-like cells (HLCs) from human iPS cells those show the morphologic and phenotypic properties of primary human hepatocytes. An experimental study. Department of Surgery, Okayama University, Graduate School of Medicine, Japan, from April to December 2011. Human iPS cells were generated and maintained on ES qualified matrigel coated plates supplemented with mTeSR medium or alternatively on mitotically inactivated MEF feeder layer in DMEM/F12 medium containing 20% KOSR, 4ng/ml bFGF-2, 1 x 10-4 M 2-mercaptoethanol, 1 mmol/L NEAA, 2mM L-glutamine and 1% penicillin-streptomycin. iPS cells were differentiated to HLCs by sequential culture using a four step differentiation protocol: (I) Generation of embryoid bodies (EBs) in suspension culture; (II) Induction of definitive endoderm (DE) from 2 days old EBs by growth in human activin-A (100 ng/ml) and basic fibroblasts growth factor (bFGF2) (100 ng/ml) on matrigel coated plates; (III) Induction of hepatic progenitors by co-culture with non-parenchymal human hepatic stellate cell line (TWNT-1); and (IV) Maturation by culture in dexamethasone. Characterization was performed by RT-PCR and functional assays. The generated HLCs showed microscopically morphological phenotype of human hepatocytes, expressed liver-specific genes (ASGPR, Albumin, AFP, Sox17, Fox A2), secreted human liver-specific proteins such as albumin, synthesized urea and metabolized ammonia. Functional HLCs were generated from human iPS cells, which could be used for autologus hepatocyte transplantation for liver failure and as in vitro model for determining the metabolic and toxicological properties of drug compounds.

Common elements in interleukin 4 and insulin signaling pathways in factor-dependent hematopoietic cells.

PubMed

Wang, L M; Keegan, A D; Li, W; Lienhard, G E; Pacini, S; Gutkind, J S; Myers, M G; Sun, X J; White, M F; Aaronson, S A

1993-05-01

Interleukin 4 (IL-4), insulin, and insulin-like growth factor I (IGF-I) efficiently induced DNA synthesis in the IL-3-dependent murine myeloid cell lines FDC-P1 and FDC-P2. Although these factors could not individually sustain long-term growth of these lines, a combination of IL-4 with either insulin or IGF-I did support continuous growth. The principal tyrosine-phosphorylated substrate observed in FDC cells stimulated with IL-4, previously designated 4PS, was of the same size (170 kDa) as the major substrate phosphorylated in response to insulin or IGF-I. These substrates had phosphopeptides of the same size when analyzed by digestion with Staphylococcus aureus V8 protease, and each tightly associated with the 85-kDa component of phosphatidylinositol 3-kinase after factor stimulation. IRS-1, the principal substrate phosphorylated in response to insulin or IGF-I stimulation in nonhematopoietic cells, is similar in size to 4PS. However, anti-IRS-1 antibodies failed to efficiently precipitate 4PS, and some phosphopeptides generated by V8 protease digestion of IRS-1 were distinct in size from the phosphopeptides of 4PS. Nevertheless, IL-4, insulin, and IGF-I were capable of stimulating tyrosine phosphorylation of IRS-1 in FDC cells that expressed this substrate as a result of transfection. These findings indicate that (i) IL-4, insulin, and IGF-I use signal transduction pathways in FDC lines that have at least one major feature in common, the rapid tyrosine phosphorylation of 4PS, and (ii) insulin and IGF-I stimulation of hematopoietic cell lines leads to the phosphorylation of a substrate that may be related to but is not identical to IRS-1.

Common elements in interleukin 4 and insulin signaling pathways in factor-dependent hematopoietic cells.

PubMed Central

Wang, L M; Keegan, A D; Li, W; Lienhard, G E; Pacini, S; Gutkind, J S; Myers, M G; Sun, X J; White, M F; Aaronson, S A

1993-01-01

Interleukin 4 (IL-4), insulin, and insulin-like growth factor I (IGF-I) efficiently induced DNA synthesis in the IL-3-dependent murine myeloid cell lines FDC-P1 and FDC-P2. Although these factors could not individually sustain long-term growth of these lines, a combination of IL-4 with either insulin or IGF-I did support continuous growth. The principal tyrosine-phosphorylated substrate observed in FDC cells stimulated with IL-4, previously designated 4PS, was of the same size (170 kDa) as the major substrate phosphorylated in response to insulin or IGF-I. These substrates had phosphopeptides of the same size when analyzed by digestion with Staphylococcus aureus V8 protease, and each tightly associated with the 85-kDa component of phosphatidylinositol 3-kinase after factor stimulation. IRS-1, the principal substrate phosphorylated in response to insulin or IGF-I stimulation in nonhematopoietic cells, is similar in size to 4PS. However, anti-IRS-1 antibodies failed to efficiently precipitate 4PS, and some phosphopeptides generated by V8 protease digestion of IRS-1 were distinct in size from the phosphopeptides of 4PS. Nevertheless, IL-4, insulin, and IGF-I were capable of stimulating tyrosine phosphorylation of IRS-1 in FDC cells that expressed this substrate as a result of transfection. These findings indicate that (i) IL-4, insulin, and IGF-I use signal transduction pathways in FDC lines that have at least one major feature in common, the rapid tyrosine phosphorylation of 4PS, and (ii) insulin and IGF-I stimulation of hematopoietic cell lines leads to the phosphorylation of a substrate that may be related to but is not identical to IRS-1. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:7683417

The use of a proteinaceous "cushion" with a polystyrene-binding peptide tag to control the orientation and function of a target peptide adsorbed to a hydrophilic polystyrene surface.

PubMed

Imanaka, Hiroyuki; Yamadzumi, Daisuke; Yanagita, Keisuke; Ishida, Naoyuki; Nakanishi, Kazuhiro; Imamura, Koreyoshi

2016-03-01

In immobilizing target biomolecules on a solid surface, it is essential (i) to orient the target moiety in a preferred direction and (ii) to avoid unwanted interactions of the target moiety including with the solid surface. The preferred orientation of the target moiety can be achieved by genetic conjugation of an affinity peptide tag specific to the immobilization surface. Herein, we report on a strategy for reducing the extent of direct interaction between the target moiety and surface in the immobilization of hexahistidine peptide (6His) and green fluorescent protein (GFP) on a hydrophilic polystyrene (PS) surface: Ribonuclease HII from Thermococcus kodakaraensis (cHII) was genetically inserted as a "cushion" between the PS-affinity peptide tag and target moiety. The insertion of a cushion protein resulted in a considerably stronger immobilization of target biomolecules compared to conjugation with only a PS affinity peptide tag, resulting in a substantially enhanced accessibility of the detection antibody to the target 6His peptide. The fluorescent intensity of the GFP moiety was decreased by approximately 30% as the result of fusion with cHII and the PS-affinity peptide tag but was fully retained in the immobilization on the PS surface irrespective of the increased binding force. Furthermore, the fusion of cHII did not impair the stability of the target GFP moiety. Accordingly, the use of a proteinaceous cushion appears to be promising for the immobilization of functional biomolecules on a solid surface. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:527-534, 2016. © 2016 American Institute of Chemical Engineers.

RAId_aPS: MS/MS Analysis with Multiple Scoring Functions and Spectrum-Specific Statistics

PubMed Central

Alves, Gelio; Ogurtsov, Aleksey Y.; Yu, Yi-Kuo

2010-01-01

Statistically meaningful comparison/combination of peptide identification results from various search methods is impeded by the lack of a universal statistical standard. Providing an -value calibration protocol, we demonstrated earlier the feasibility of translating either the score or heuristic -value reported by any method into the textbook-defined -value, which may serve as the universal statistical standard. This protocol, although robust, may lose spectrum-specific statistics and might require a new calibration when changes in experimental setup occur. To mitigate these issues, we developed a new MS/MS search tool, RAId_aPS, that is able to provide spectrum-specific -values for additive scoring functions. Given a selection of scoring functions out of RAId score, K-score, Hyperscore and XCorr, RAId_aPS generates the corresponding score histograms of all possible peptides using dynamic programming. Using these score histograms to assign -values enables a calibration-free protocol for accurate significance assignment for each scoring function. RAId_aPS features four different modes: (i) compute the total number of possible peptides for a given molecular mass range, (ii) generate the score histogram given a MS/MS spectrum and a scoring function, (iii) reassign -values for a list of candidate peptides given a MS/MS spectrum and the scoring functions chosen, and (iv) perform database searches using selected scoring functions. In modes (iii) and (iv), RAId_aPS is also capable of combining results from different scoring functions using spectrum-specific statistics. The web link is http://www.ncbi.nlm.nih.gov/CBBresearch/Yu/raid_aps/index.html. Relevant binaries for Linux, Windows, and Mac OS X are available from the same page. PMID:21103371

Roles of platelet STIM1 and Orai1 in glycoprotein VI- and thrombin-dependent procoagulant activity and thrombus formation.

PubMed

Gilio, Karen; van Kruchten, Roger; Braun, Attila; Berna-Erro, Alejandro; Feijge, Marion A H; Stegner, David; van der Meijden, Paola E J; Kuijpers, Marijke J E; Varga-Szabo, David; Heemskerk, Johan W M; Nieswandt, Bernhard

2010-07-30

In platelets, STIM1 has been recognized as the key regulatory protein in store-operated Ca(2+) entry (SOCE) with Orai1 as principal Ca(2+) entry channel. Both proteins contribute to collagen-dependent arterial thrombosis in mice in vivo. It is unclear whether STIM2 is involved. A key platelet response relying on Ca(2+) entry is the surface exposure of phosphatidylserine (PS), which accomplishes platelet procoagulant activity. We studied this response in mouse platelets deficient in STIM1, STIM2, or Orai1. Upon high shear flow of blood over collagen, Stim1(-/-) and Orai1(-/-) platelets had greatly impaired glycoprotein (GP) VI-dependent Ca(2+) signals, and they were deficient in PS exposure and thrombus formation. In contrast, Stim2(-/-) platelets reacted normally. Upon blood flow in the presence of thrombin generation and coagulation, Ca(2+) signals of Stim1(-/-) and Orai1(-/-) platelets were partly reduced, whereas the PS exposure and formation of fibrin-rich thrombi were normalized. Washed Stim1(-/-) and Orai1(-/-) platelets were deficient in GPVI-induced PS exposure and prothrombinase activity, but not when thrombin was present as co-agonist. Markedly, SKF96365, a blocker of (receptor-operated) Ca(2+) entry, inhibited Ca(2+) and procoagulant responses even in Stim1(-/-) and Orai1(-/-) platelets. These data show for the first time that: (i) STIM1 and Orai1 jointly contribute to GPVI-induced SOCE, procoagulant activity, and thrombus formation; (ii) a compensating Ca(2+) entry pathway is effective in the additional presence of thrombin; (iii) platelets contain two mechanisms of Ca(2+) entry and PS exposure, only one relying on STIM1-Orai1 interaction.

[Isolation and characterization of petroleum catabolic broad-host-range plasmids from Shen-Fu wastewater irrigation zone].

PubMed

Wang, Ya-Fei; Wang, Ya-Fei; Li, Hui; Li, Xiao-Bin

2013-11-01

Based on triparental mating, we isolated a total of eight broad host range (BHR) petroleum hydrocarbon catabolic plasmids from the soils, sediments, and wastewater samples in the Shen-Fu irrigation zone. The antibiotic resistance of the plasmids was tested, and then, the plasmids were transferred to Escherichia coli EC100. The plasmids carrying no antibiotic resistance were tagged by miniTn5 transposon consisting of antibiotic resistant genes. The PCR-based incompatibility test revealed that the pS3-2C and pS4-6G belonged to Inc P group, the pS3-2G, pW22-3G, and pA15-7G belonged to Inc N group, the pS7-2G was identified as Inc W plasmid, and the pA23-1G and pA10-1C were placed into Inc Q group. By adopting the reported PCR amplification methods of petroleum hydrocarbon-degrading catabolic genes, the petroleum-degrading capability of these BHR plasmids were preliminarily analyzed. The plasmids pS3-2G, pS7-2G, pA23-1G, pW22-3G, and pA10-1C carried aromatic ring- hydroxylating dioxygenase gene phdA and toluene monooxygenase gene touA; the plasmid pA15-7G carried touA and toluene dioxygenase gene tod; the plasmid pS3-2C carried ben, phdA, and tod; whereas the pS4-6G only carried ben. The host range test showed that all the isolated plasmids except pS3-2C could be transferred and maintained stably in the representative strains Agrobacterium tumefaciens C58, Cupriavidus necator JMP228, and E. coli EC100 of the alpha-, beta-, and gamma-Proteobacteria, respectively.

[Efficacy of different preparations of budesonide combined with pulmonary surfactant in the treatment of neonatal respiratory distress syndrome: a comparative analysis].

PubMed

Ke, Hua; Li, Zhan-Kui; Yu, Xi-Ping; Guo, Jin-Zhen

2016-05-01

To study the efficacy of different preparations of budesonide combined with pulmonary surfactant (PS) in improving blood gas levels and preventing bronchopulmonary dysplasia (BPD) in preterm infants with neonatal respiratory distress syndrome (NRDS). A total of 184 preterm infants who developed NRDS within 4 hours after birth were randomly administered with PS + continuous inhalation of budesonide aerosol (continuous aerosol group), PS+budesonide solution (solution group), PS + single inhalation of budesonide aerosol (single aerosol group), and PS alone, with 46 neonates in each group. The changes in arterial blood gas levels, rate of invasive mechanical ventilation after treatment, time of assisted ventilation, rate of repeated use of PS, and the incidence of BPD were compared between the four groups. On the 2nd to 4th day after treatment, pH, PCO2, and oxygenation index (FiO2/PaO2) showed significant differences among the four groups, and the continuous aerosol group showed the most improvements of all indicators, followed by the solution group, single aerosol group, and PS alone group. The continuous aerosol group had a significantly shorter time of assisted ventilation than the other three groups (P<0.05). The solution group had a significantly shorter time of assisted ventilation than the single aerosol and PS alone groups (P<0.05). The rate of invasive mechanical ventilation after treatment, rate of repeated use of PS, and incidence of BPD showed significant differences among the four groups (P<0.05), and the continuous aerosol group had the lowest rates, followed by the solution group. A combination of PS and continuous inhalation of budesonide aerosol has a better efficacy in the treatment of NRDS than a combination of PS and budesonide solution. The difference in reducing the incidence of BDP between the two administration methods awaits further investigation with a larger sample size.

Association of cross-sectional area of the rectus capitis posterior minor muscle with active trigger points in chronic tension-type headache: a pilot study.

PubMed

Fernández-de-Las-Peñas, César; Cuadrado, María Luz; Arendt-Nielsen, Lars; Ge, Hong-You; Pareja, Juan A

2008-03-01

To investigate whether cross-sectional area (CSA) of the suboccipital muscles was associated with active trigger points (TrPs) in chronic tension-type headache (CTTH). Magnetic resonance imaging (MRI) of the cervical spine was performed in 11 females with CTTH aged from 26 to 50 yrs old. CSA for both rectus capitis posterior minor (RCPmin) and rectus capitis posterior major (RCPmaj) muscles were measured from axial T1-weighted images, using axial MRI slices aligned parallel to the C2/3 intervertebral disc. A headache diary was kept for 4 wks to record the pain history. TrPs in the suboccipital muscle were identified by eliciting referred pain to palpation, and increased referred pain with muscle contraction. TrPs were considered active if the elicited referred pain reproduced the head pain pattern and features of the pattern seen during spontaneous headache attacks. Active TrPs were found in six patients (55%), whereas the remaining five patients showed latent TrPs. CSA of the RCPmin was significantly smaller (F = 13.843; P = 0.002) in the patients with active TrPs (right side: 55.9 +/- 4.4 mm; left side: 61.1 +/-: 3.8 mm) than in patients with latent TrPs (right side: 96.9 +/- 14.4 mm; left side: 88.7 +/- 9.7 mm). No significant differences were found for CSA of the RCPmaj between the patients with either active or latent TrP (P > 0.5). It seems that muscle atrophy in the RCPmin, but not in the RCPmaj, was associated with suboccipital active TrPs in CTTH, although studies with larger sample sizes are now required. It may be that nociceptive inputs in active TrPs could lead to muscle atrophy of the involved muscles. Muscle disuse or avoidance behavior can also be involved in atrophy.

From Decent Work to Decent Lives: Positive Self and Relational Management (PS&RM) in the Twenty-First Century

PubMed Central

Di Fabio, Annamaria; Kenny, Maureen E.

2016-01-01

The aim of the present study is to empirically test the theoretical model, Positive Self and Relational Management (PS&RM), for a sample of 184 Italian university students. The PS&RM model specifies the development of individuals' strengths, potentials, and talents across the lifespan and with regard to the dialect of self in relationship. PS&RM is defined theoretically by three constructs: Positive Lifelong Life Management, Positive Lifelong Self-Management, Positive Lifelong Relational Management. The three constructs are operationalized as follows: Positive Lifelong Life Management is measured by the Positive and Negative Affect Schedule (PANAS), the Satisfaction With Life Scale (SWLS), the Meaningful Life Measure (MLM), and the Authenticity Scale (AS); Positive Lifelong Self-Management is measured by the Intrapreneurial Self-Capital Scale (ISC), the Career Adapt-Abilities Scale (CAAS), and the Life Project Reflexivity Scale (LPRS); and Positive Lifelong Relational Management is measured by the Trait Emotional Intelligence Questionnaire (TEIQue), the Multidimensional Scale for Perceived Social Support (MSPSS), and the Positive Relational Management Scale (PRMS). Confirmatory factor analysis of the PS&RM model was completed using structural equation modeling. The theoretical PS&RM model was empirically tested as defined by the three hypothesized constructs. Empirical support for this model offers a framework for further research and the design of preventive interventions to promote decent work and decent lives in the twenty-first century. PMID:27047406

Simple and Sensitive Quantification of MicroRNAs via PS@Au Microspheres-Based DNA Probes and DSN-Assisted Signal Amplification Platform.

PubMed

Zhao, Qian; Piao, Jiafang; Peng, Weipan; Wang, Yang; Zhang, Bo; Gong, Xiaoqun; Chang, Jin

2018-01-31

Identifying the microRNA (miRNA) expression level can provide critical information for early diagnosis of cancers or monitoring the cancer therapeutic efficacy. This paper focused on a kind of gold-nanoparticle-coated polystyrene microbeads (PS@Au microspheres)-based DNA probe as miRNA capture and duplex-specific nuclease (DSN) signal amplification platform based on an RGB value readout for detection of miRNAs. In virtue of the outstanding selectivity and simple experimental operation, 5'-fluorochrome-labeled molecular beacons (MBs) were immobilized on PS@Au microspheres via their 3'-thiol, in the wake of the fluorescence quenching by nanoparticle surface energy transfer (NSET). Target miRNAs were captured by the PS@Au microspheres-based DNA probe through DNA/RNA hybridization. DSN enzyme subsequently selectively cleaved the DNA to recycle the target miRNA and release of fluorophores, thereby triggering the signal amplification with more free fluorophores. The RGB value measurement enabled a detection limit of 50 fM, almost 4 orders of magnitude lower than PS@Au microspheres-based DNA probe detection without DSN. Meanwhile, by different encoding of dyes, miRNA-21 and miRNA-10b were simultaneously detected in the same sample. Considering the ability for quantitation, high sensitivity, and convenient merits, the PS@Au microspheres-based DNA probe and DSN signal amplification platform supplied valuable information for early diagnosis of cancers.

Surface adsorption behaviour of milk whey protein and pectin mixtures under conditions of air-water interface saturation.

PubMed

Perez, Adrián A; Sánchez, Cecilio Carrera; Patino, Juan M Rodríguez; Rubiolo, Amelia C; Santiago, Liliana G

2011-07-01

Milk whey proteins (MWP) and pectins (Ps) are biopolymer ingredients commonly used in the manufacture of colloidal food products. Therefore, knowledge of the interfacial characteristics of these biopolymers and their mixtures is very important for the design of food dispersion formulations (foams and/or emulsions). In this paper, we examine the adsorption and surface dilatational behaviour of MWP/Ps systems under conditions in which biopolymers can saturate the air-water interface on their own. Experiments were performed at constant temperature (20 °C), pH 7 and ionic strength 0.05 M. Two MWP samples, β-lactoglobulin (β-LG) and whey protein concentrate (WPC), and two Ps samples, low-methoxyl pectin (LMP) and high-methoxyl pectin (HMP) were evaluated. The contribution of biopolymers (MWP and Ps) to the interfacial properties of mixed systems was evaluated on the basis of their individual surface molecular characteristics. Biopolymer bulk concentration capable of saturating the air-water interface was estimated from surface pressure isotherms. Under conditions of interfacial saturation, dynamic adsorption behaviour (surface pressure and dilatational rheological characteristics) of MWP/Ps systems was discussed from a kinetic point of view, in terms of molecular diffusion, penetration and configurational rearrangement at the air-water interface. The main adsorption mechanism in MWP/LMP mixtures might be the MWP interfacial segregation due to the thermodynamic incompatibility between MWP and LMP (synergistic mechanism); while the interfacial adsorption in MWP/HMP mixtures could be characterized by a competitive mechanism between MWP and HMP at the air-water interface (antagonistic mechanism). The magnitude of these phenomena could be closely related to differences in molecular composition and/or aggregation state of MWP (β-LG and WPC). Copyright © 2011 Elsevier B.V. All rights reserved.

Carbon and nitrogen co-doped bowl-like Au/TiO2 nanostructures with tunable size for enhanced visible-light-driven photocatalysis

NASA Astrophysics Data System (ADS)

Li, Yayuan; Cao, Shubo; Zhang, Ang; Zhang, Chen; Qu, Ting; Zhao, Yongbin; Chen, Aihua

2018-07-01

It is of great importance to extend the UV response of anatase TiO2 into the visible light range for the practical applications. Here, a facile rout to carbon and nitrogen co-doped, Au loaded bowl-like TiO2 nanostructures with tunable size are proposed by using self-assembled polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) block copolymer (BCP) spherical micelles as templates. Amphiphilic PS-b-P4VP self-assembles to form PS@P4VP core-shell spherical micelles with P4VP as the out layer in an evaporable mixed solvents of ethanol/tetrahydrofuran (THF). The size of uniform PS@P4VP spherical micelles can be precisely tuned in the range of a few nm to several hundred nm by controlling the molecular composition of the BCPs. Bowl-like TiO2 nanostructures with a replicate size loaded with highly dispersed Au nanoparticles (NPs) of ∼5 nm in diameter are fabricated from these spherical micelles because of strong complex ability of pyridine groups. PS-b-P4VP provides carbon and nitrogen sources to dope the resulting samples simultaneously. The special carbon and nitrogen co-doped bowl-like Au/TiO2 nanostructures exhibit much higher photocatalytic activity in the photodegradation of rhodamine B (RhB) compared to Au/P25 under visible light irradiation. Furthermore, the photocatalytic activity is significantly influenced by the BCP molecular composition due to different surface area and loading capacity of the resulting samples. This study provides a facile way to synthesize multi-element doped hollow or bowl-like nanoparticles with tunable size in the nanometer range which have potential application at photocatalysis, oxygen reduction reaction, etc.

Measurement of the bottom hadron lifetime at the Z 0 resonancce

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

Fujino, Donald Hideo

1992-06-01

We have measured the bottom hadron lifetime from bmore » $$\\bar{b}$$ events produced at the Z 0 resonance. Using the precision vertex detectors of the Mark II detector at the Stanford Linear Collider, we developed an impact parameter tag to identify bottom hadrons. The vertex tracking system resolved impact parameters to 30 μm for high momentum tracks, and 70 μm for tracks with a momentum of 1 GeV. We selected B hadrons with an efficiency of 40% and a sample purity of 80%, by requiring there be at least two tracks in a single jet that significantly miss the Z 0 decay vertex. From a total of 208 hadronic Z 0 events collected by the Mark II detector in 1990, we tagged 53 jets, of which 22 came from 11 double-tagged events. The jets opposite the tagged ones, referred as the ``untagged`` sample, are rich in B hadrons and unbiased in B decay times. The variable Σδ is the sum of impact parameters from tracks in the jet, and contains vital information on the B decay time. We measured the B lifetime from a one-parameter likelihood fit to the untagged Σδ distribution, obtaining τ b = 1.53 $$+0.55\\atop{-0.45}$$ ± 0.16 ps which agrees with the current world average. The first error is statistical and the second is systematic. The systematic error was dominated by uncertainties in the track resolution function. As a check, we also obtained consistent results using the Σδ distribution from the tagged jets and from the entire hadronic sample without any bottom enrichment.« less

Measurement of the bottom hadron lifetime at the Z sup 0 resonancce

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

Fujino, D.H.

1992-06-01

We have measured the bottom hadron lifetime from b{bar b} events produced at the Z{sup 0} resonance. Using the precision vertex detectors of the Mark II detector at the Stanford Linear Collider, we developed an impact parameter tag to identify bottom hadrons. The vertex tracking system resolved impact parameters to 30 {mu}m for high momentum tracks, and 70 {mu}m for tracks with a momentum of 1 GeV. We selected B hadrons with an efficiency of 40% and a sample purity of 80%, by requiring there be at least two tracks in a single jet that significantly miss the Z{sup 0}more » decay vertex. From a total of 208 hadronic Z{sup 0} events collected by the Mark II detector in 1990, we tagged 53 jets, of which 22 came from 11 double-tagged events. The jets opposite the tagged ones, referred as the untagged'' sample, are rich in B hadrons and unbiased in B decay times. The variable {Sigma}{delta} is the sum of impact parameters from tracks in the jet, and contains vital information on the B decay time. We measured the B lifetime from a one-parameter likelihood fit to the untagged {Sigma}{delta} distribution, obtaining {tau}{sub b} = 1.53{sub {minus}0.45}{sup +0.55}{plus minus}0.16 ps which agrees with the current world average. The first error is statistical and the second is systematic. The systematic error was dominated by uncertainties in the track resolution function. As a check, we also obtained consistent results using the {Sigma}{delta} distribution from the tagged jets and from the entire hadronic sample without any bottom enrichment.« less

Polarization-sensitive optical coherence tomography measurements with different phase modulation amplitude when using continuous polarization modulation

NASA Astrophysics Data System (ADS)

Lu, Zenghai; Kasaragod, Deepa K.; Matcher, Stephen J.

2012-01-01

We demonstrate theoretically and experimentally that the phase retardance and relative optic-axis orientation of a sample can be calculated without prior knowledge of the actual value of the phase modulation amplitude when using a polarization-sensitive optical coherence tomography system based on continuous polarization modulation (CPM-PS-OCT). We also demonstrate that the sample Jones matrix can be calculated at any values of the phase modulation amplitude in a reasonable range depending on the system effective signal-to-noise ratio. This has fundamental importance for the development of clinical systems by simplifying the polarization modulator drive instrumentation and eliminating its calibration procedure. This was validated on measurements of a three-quarter waveplate and an equine tendon sample by a fiber-based swept-source CPM-PS-OCT system.

Hyperspectral anomaly detection using Sony PlayStation 3

NASA Astrophysics Data System (ADS)

Rosario, Dalton; Romano, João; Sepulveda, Rene

2009-05-01

We present a proof-of-principle demonstration using Sony's IBM Cell processor-based PlayStation 3 (PS3) to run-in near real-time-a hyperspectral anomaly detection algorithm (HADA) on real hyperspectral (HS) long-wave infrared imagery. The PS3 console proved to be ideal for doing precisely the kind of heavy computational lifting HS based algorithms require, and the fact that it is a relatively open platform makes programming scientific applications feasible. The PS3 HADA is a unique parallel-random sampling based anomaly detection approach that does not require prior spectra of the clutter background. The PS3 HADA is designed to handle known underlying difficulties (e.g., target shape/scale uncertainties) often ignored in the development of autonomous anomaly detection algorithms. The effort is part of an ongoing cooperative contribution between the Army Research Laboratory and the Army's Armament, Research, Development and Engineering Center, which aims at demonstrating performance of innovative algorithmic approaches for applications requiring autonomous anomaly detection using passive sensors.