A Comprehensive Analysis of Uncertainties Affecting the Stellar Mass-Halo Mass Relation for 0

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

Behroozi, Peter S.; Conroy, Charlie; Wechsler, Risa H.

2010-06-07

We conduct a comprehensive analysis of the relationship between central galaxies and their host dark matter halos, as characterized by the stellar mass - halo mass (SM-HM) relation, with rigorous consideration of uncertainties. Our analysis focuses on results from the abundance matching technique, which assumes that every dark matter halo or subhalo above a specific mass threshold hosts one galaxy. We provide a robust estimate of the SM-HM relation for 0 < z < 1 and discuss the quantitative effects of uncertainties in observed galaxy stellar mass functions (GSMFs) (including stellar mass estimates and counting uncertainties), halo mass functions (includingmore » cosmology and uncertainties from substructure), and the abundance matching technique used to link galaxies to halos (including scatter in this connection). Our analysis results in a robust estimate of the SM-HM relation and its evolution from z=0 to z=4. The shape and evolution are well constrained for z < 1. The largest uncertainties at these redshifts are due to stellar mass estimates (0.25 dex uncertainty in normalization); however, failure to account for scatter in stellar masses at fixed halo mass can lead to errors of similar magnitude in the SM-HM relation for central galaxies in massive halos. We also investigate the SM-HM relation to z = 4, although the shape of the relation at higher redshifts remains fairly unconstrained when uncertainties are taken into account. We find that the integrated star formation at a given halo mass peaks at 10-20% of available baryons for all redshifts from 0 to 4. This peak occurs at a halo mass of 7 x 10{sup 11} M{sub {circle_dot}} at z = 0 and this mass increases by a factor of 5 to z = 4. At lower and higher masses, star formation is substantially less efficient, with stellar mass scaling as M{sub *} {approx} M{sub h}{sup 2.3} at low masses and M{sub *} {approx} M{sub h}{sup 0.29} at high masses. The typical stellar mass for halos with mass less than 10{sup 12} M{sub {circle_dot}} has increased by 0.3-0.45 dex for halos since z {approx} 1. These results will provide a powerful tool to inform galaxy evolution models.« less

First analysis of eight Algol-type binaries: EI Aur, XY Dra, BP Dra, DD Her, VX Lac, WX Lib, RZ Lyn, and TY Tri

NASA Astrophysics Data System (ADS)

Zasche, P.

2016-01-01

The available photometry from the online databases were used for the first light curve analysis of eight eclipsing binary systems EI Aur, XY Dra, BP Dra, DD Her, VX Lac, WX Lib, RZ Lyn, and TY Tri. All these stars are of Algol-type, having the detached components and the orbital periods from 0.92 to 6.8 days. For the systems EI Aur and BP Dra the large amount of the third light was detected during the light curve solution. Moreover, 468 new times of minima for these binaries were derived, trying to identify the period variations. For the systems XY Dra and VX Lac the third bodies were detected with the periods 17.7, and 49.3 years, respectively.

Missing Fe: hydrogenated iron nanoparticles

NASA Astrophysics Data System (ADS)

Bilalbegović, G.; Maksimović, A.; Mohaček-Grošev, V.

2017-03-01

Although it was found that the FeH lines exist in the spectra of some stars, none of the spectral features in the interstellar medium (ISM) have been assigned to this molecule. We suggest that iron atoms interact with hydrogen and produce Fe-H nanoparticles which sometimes contain many H atoms. We calculate infrared spectra of hydrogenated iron nanoparticles using density functional theory methods and find broad, overlapping bands. Desorption of H2 could induce spinning of these small Fe-H dust grains. Some of hydrogenated iron nanoparticles possess magnetic and electric moments and should interact with electromagnetic fields in the ISM. FenHm nanoparticles could contribute to the polarization of the ISM and the anomalous microwave emission. We discuss the conditions required to form FeH and FenHm in the ISM.

The Magnetic Field Structure of W3(OH)

NASA Astrophysics Data System (ADS)

El-Batal, Adham M.; Clemens, Dan P.; Montgomery, Jordan

2018-06-01

Situated in the Perseus arm of the Galaxy, the W3 molecular cloud is a high-mass star-forming region with low foreground optical extinction. Near-infrared H- and K-band polarimetric observations of a 10' × 10' field of view of W3 were obtained using the Mimir instrument on the 1.8 m Perkins Telescope. This field of view encompasses W3(OH), a region of OH and H2O masers as well as an HII region. The H-band data were used in conjunction with Spitzer M-band data to map extinction via H-M color excess. In total, 2654 stellar objects were found in the Mimir field of view, of which 1013 had H and M magnitudes with low errors. Using the extinction map and the individual stellar H-M color excess values, 429 stars with polarized signals were found to be background to the molecular cloud. These were useful for mapping the magnetic field structure and estimating the magnetic field strength of the cloud. Mid- to far-infrared (70 - 870 μm) archival Herschel and Planck data were used to map dust extinction at 850 µm and create an H2 column density map. Combined, maps of magnetic field strength and hydrogen column density can be used to infer the ratio of gravitational potential to magnetic potential ( M/Φ ). Findings are discussed in the context of M/Φ ratio in models and the stability of high-mass star-forming regions.This work has been supported by NSF AST14-12269 and NASA NNX15AE51G grants.

Hydrodynamical study on the conversion of hadronic matter to quark matter: I. Shock-induced conversion

NASA Astrophysics Data System (ADS)

Furusawa, Shun; Sanada, Takahiro; Yamada, Shoichi

2016-02-01

We study transitions of hadronic matter (HM) to three-flavor quark matter (3QM) locally, regarding the conversion processes as combustion and describing them hydrodynamically. Not only the jump condition on both sides of the conversion front but the structures inside the front are also considered by taking into account what happens during the conversion processes on the time scale of weak interactions as well as equations of state (EOSs) in the mixed phase. Under the assumption that HM is metastable with their free energies being larger than those of 3QM but smaller than those of two-flavor quark matter (2QM), we consider the transition via 2QM triggered by a rapid density rise in a shock wave. Based on the results, we discuss which combustion modes (strong/weak detonation) may be realized. HM is described by an EOS based on the relativistic mean field theory, and 2QMs and 3QMs are approximated by the MIT bag model. We demonstrate for a wide range of the bag constant and strong coupling constant in this combination of EOSs that the combustion may occur in the so-called endothermic regime, in which the Hugoniot curve for combustion runs below the one for the shock wave in the p -V plane and which has no terrestrial counterpart. Elucidating the essential features in this scenario first by a toy model, we then analyze more realistic models. We find that strong detonation always occurs. Depending on the EOS of quark matter as well as the density of HM and the Mach number of the detonation front, deconfinement from HM to 2QM is either completed or not completed in the shock wave. In the latter case, which is more likely if the EOS of quark matter ensures that deconfinement occurs above the nuclear saturation density and that the maximum mass of cold quark stars is larger than 2 M⊙, the conversion continues further via the mixing state of HM and 3QM on the time scale of weak interactions.

Study of diffuse H II regions potentially forming part of the gas streams around Sgr A*

NASA Astrophysics Data System (ADS)

Armijos-Abendaño, J.; López, E.; Martín-Pintado, J.; Báez-Rubio, A.; Aravena, M.; Requena-Torres, M. A.; Martín, S.; Llerena, M.; Aldás, F.; Logan, C.; Rodríguez-Franco, A.

2018-05-01

We present a study of diffuse extended ionized gas towards three clouds located in the Galactic Centre (GC). One line of sight (LOS) is towards the 20 km s-1 cloud (LOS-0.11) in the Sgr A region, another LOS is towards the 50 km s-1 cloud (LOS-0.02), also in Sgr A, while the third is towards the Sgr B2 cloud (LOS+0.693). The emission from the ionized gas is detected from Hnα and Hmβ radio recombination lines (RRLs). Henα and Hemβ RRL emission is detected with the same n and m as those from the hydrogen RRLs only towards LOS+0.693. RRLs probe gas with positive and negative velocities towards the two Sgr A sources. The Hmβ to Hnα ratios reveal that the ionized gas is emitted under local thermodynamic equilibrium conditions in these regions. We find a He to H mass fraction of 0.29±0.01 consistent with the typical GC value, supporting the idea that massive stars have increased the He abundance compared to its primordial value. Physical properties are derived for the studied sources. We propose that the negative velocity component of both Sgr A sources is part of gas streams considered previously to model the GC cloud kinematics. Associated massive stars with what are presumably the closest H II regions to LOS-0.11 (positive velocity gas), LOS-0.02, and LOS+0.693 could be the main sources of ultraviolet photons ionizing the gas. The negative velocity components of both Sgr A sources might be ionized by the same massive stars, but only if they are in the same gas stream.

Nuclear Physical Uncertainties in Modeling X-Ray Bursts

NASA Astrophysics Data System (ADS)

Regis, Eric; Amthor, A. Matthew

2017-09-01

Type I x-ray bursts occur when a neutron star accretes material from the surface of another star in a compact binary star system. For certain accretion rates and material compositions, much of the nuclear material is burned in short, explosive bursts. Using a one-dimensional stellar model, Kepler, and a comprehensive nuclear reaction rate library, ReacLib, we have simulated chains of type I x-ray bursts. Unfortunately, there are large remaining uncertainties in the nuclear reaction rates involved, since many of the isotopes reacting are unstable and have not yet been studied experimentally. Some individual reactions, when varied within their estimated uncertainty, alter the light curves dramatically. This limits our ability to understand the structure of the neutron star. Previous studies have looked at the effects of individual reaction rate uncertainties. We have applied a Monte Carlo method ``-simultaneously varying a set of reaction rates'' -in order to probe the expected uncertainty in x-ray burst behaviour due to the total uncertainty in all nuclear reaction rates. Furthermore, we aim to discover any nonlinear effects due to the coupling between different reaction rates. Early results show clear non-linear effects. This research was made possible by NSF-DUE Grant 1317446, BUScholars Program.

Theoretical Limits of Energy Density in Silicon-Carbon Composite Anode Based Lithium Ion Batteries.

PubMed

Dash, Ranjan; Pannala, Sreekanth

2016-06-17

Silicon (Si) is under consideration as a potential next-generation anode material for the lithium ion battery (LIB). Experimental reports of up to 40% increase in energy density of Si anode based LIBs (Si-LIBs) have been reported in literature. However, this increase in energy density is achieved when the Si-LIB is allowed to swell (volumetrically expand) more than graphite based LIB (graphite-LIB) and beyond practical limits. The volume expansion of LIB electrodes should be negligible for applications such as automotive or mobile devices. We determine the theoretical bounds of Si composition in a Si-carbon composite (SCC) based anode to maximize the volumetric energy density of a LIB by constraining the external dimensions of the anode during charging. The porosity of the SCC anode is adjusted to accommodate the volume expansion during lithiation. The calculated threshold value of Si was then used to determine the possible volumetric energy densities of LIBs with SCC anode (SCC-LIBs) and the potential improvement over graphite-LIBs. The level of improvement in volumetric and gravimetric energy density of SCC-LIBs with constrained volume is predicted to be less than 10% to ensure the battery has similar power characteristics of graphite-LIBs.

Effect of Atmosphere on Collinear Double-Pulse Laser-Induced Breakdown Spectroscopy

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

Andrew J. Effenberger, Jr; Jill R. Scott

2011-07-01

Double pulse laser induced breakdown spectroscopy (DP-LIBS) has been shown to enhance LIBS spectra. Several researches have reported significant increases in signal-to-noise and or spectral intensity. In addition to DP-LIBS, atmospheric conditions can also increase spectra intensity. For example, He and Ar both increase LIBS intensity compared to air at one 1 atm. It was also found that as the pressure was decreased to 100 Torr, LIBS intensity increased in Ar and air for single pulse (SP) LIBS. In this study, a collinear DP-LIBS scheme is used along with manipulation of the atmospheric conditions. The DP-LIBS scheme consists of amore » 355 nm ablative pulse fired into a sample contained in a vacuum chamber. A second analytical 1064 nm pulse is then fired 100 ns to 10 {micro}s after and along the same path of the first pulse. Ar, He and air at pressures ranging from atmospheric pressure (630 Torr at elevation) to 10{sup -5} Torr are introduced during DP-LIBS and SP-LIBS experiments. For a brass sample, a significant increase in spectral intensity of Cu and Zn lines were observed in DP-LIBS under Ar compared to DP-LIBS in air. It was also found that Cu and Zn lines acquired with SP-LIBS in Ar are nearly as intense as DP-LIBS in air. Signal-to-noise for lines from various samples will be reported for both DP-LIBS and SP-LIBS in Ar, He, and air at pressures ranging from 630 Torr to 10{sup -5} Torr.« less

Effect of atmosphere on collinear double-pulse laser-induced breakdown spectroscopy

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

Andrew J. Effenberger, Jr.; Jill R. Scott

2010-09-01

Double pulse laser induced breakdown spectroscopy (DP-LIBS) has been shown to enhance LIBS spectra. Several researches have reported significant increases in signal-to-noise and or spectral intensity [1-4]. In addition to DP-LIBS, atmospheric conditions can also increase spectra intensity. For example, Iida [5] found that He and Ar both increase LIBS intensity compared to air at one 1 atm. It was also found that as the pressure was decreased to 100 Torr, LIBS intensity increased in Ar and air for single pulse (SP) LIBS. In this study, a collinear DP-LIBS scheme is used along with manipulation of the atmospheric conditions. Themore » DP-LIBS scheme consists of a 355 nm ablative pulse fired into a sample contained in a vacuum chamber. A second analytical 1064 nm pulse is then fired 100 ns to 10 µs after and along the same path of the first pulse. Ar, He and air at pressures ranging from atmospheric pressure (630 Torr at elevation) to 10-5 Torr are introduced during DP-LIBS and SP-LIBS experiments. For a brass sample, a significant increase in spectral intensity of Cu and Zn lines were observed in DP-LIBS under Ar compared to DP-LIBS in air (Figure 1). It was also found that Cu and Zn lines acquired with SP-LIBS in Ar are nearly as intense as DP-LIBS in air. Signal-to-noise for lines from various samples will be reported for both DP-LIBS and SP-LIBS in Ar, He, and air at pressures ranging from 630 Torr to 10-5 Torr.« less

Be Star Monitoring Using a Small Aperture Telescope and Fiber-fed Spectrograph

NASA Astrophysics Data System (ADS)

Austin, S. J.

2003-12-01

Initial results are reported from a Be star monitoring project developed for undergraduate student research involvement at a small undergraduate university using a small aperture telescope and a custom-built fiber-fed spectrograph. Beginning in 2003 June, 0.8 Angstrom/pixel resolution spectra of the H-alpha line for over forty Be stars (Omi Aqr, 4 Aql, V923 Aql, V1294 Aql, Nu 2 Boo, 24 CVn, Gamma Cas, 4 CrB, Beta Cyg, 11 Cyg, 28 Cyg, 55 Cyg, 59 Cyg, 66 Cyg, V2136 Cyg, 1 Del, CX Dra, Omi Her, Sigma Her, 4 Her, 11 Her, 88 Her, 48 Lib, Chi Oph, Zeta Oph, 51 Oph, 66 Oph, Eta PsA, V4024 Sgr, 64 Ser, Delta Sco, QR Vul, 12 Vul, 20 Vul, 25 Vul, HD142184, HD165174, HD169033, HD170235, HD174179, HD181615, HD184279, HD195554, HD201733) have been obtained. H-alpha line profile velocities and evolution are shown. Funding has been provided by the UCA University Research Council and the Arkansas Space Grant Consortium.

Quality Indicators for Human Milk Use in Very Low Birthweight Infants: Are We Measuring What We Should be Measuring?

PubMed Central

Bigger, Harold R.; Fogg, Louis J.; Patel, Aloka; Johnson, Tricia; Engstrom, Janet L.; Meier, Paula P.

2014-01-01

Objective The objective of this study was to compare the currently used human milk (HM) quality indicators that measure whether very low birthweight (VLBW; <1500 g birthweight) infants “ever” received HM and whether they were still receiving HM at discharge from the neonatal intensive care unit (NICU) to the actual amount and timing of HM received. Study Design This study used data from a large NIH-funded cohort study and calculated whether VLBW infants ever received HM (HM-Ever) and of these infants, the percentage who were still receiving HM at NICU discharge (HM-DC). Then, the HM-DC indicator (exclusive, partial and none) was compared with the amount and timing of HM feedings received by these same infants. Results Of the 291 VLBW infants who met inclusion criteria, 285 received some HM (HM-Ever = 98%). At NICU discharge (HM-DC), 24.2%, 15.1% and 60.7% were receiving exclusive, partial and no HM, respectively. Of the 60.7% infants with no HM-DC, some had received higher amounts of HM during the NICU hospitalization than infants categorized as exclusive and partial for HM-DC. Of the infants with no HM-DC, 76.8% and 59.7% had received exclusive HM during the Days 1–14 and Days 1–28 exposure periods, respectively. Conclusion The average daily dose (HM-DD; in mL/kg/d) and cumulative percentage (HM-PCT; as % of cumulative enteral intake) of HM feedings were sufficient to significantly reduce the risk of multiple morbidities, including late onset sepsis, necrotizing enterocolitis, neurocognitive delay and rehospitalization, in the majority of the VLBW infants who were discharged with no HM-DC. Quality indicators that focus on the amount and timing of HM feedings in the NICU should be added to the HM-Ever and HM-DC measures. PMID:24526005

Theoretical Limits of Energy Density in Silicon-Carbon Composite Anode Based Lithium Ion Batteries

PubMed Central

Dash, Ranjan; Pannala, Sreekanth

2016-01-01

Silicon (Si) is under consideration as a potential next-generation anode material for the lithium ion battery (LIB). Experimental reports of up to 40% increase in energy density of Si anode based LIBs (Si-LIBs) have been reported in literature. However, this increase in energy density is achieved when the Si-LIB is allowed to swell (volumetrically expand) more than graphite based LIB (graphite-LIB) and beyond practical limits. The volume expansion of LIB electrodes should be negligible for applications such as automotive or mobile devices. We determine the theoretical bounds of Si composition in a Si–carbon composite (SCC) based anode to maximize the volumetric energy density of a LIB by constraining the external dimensions of the anode during charging. The porosity of the SCC anode is adjusted to accommodate the volume expansion during lithiation. The calculated threshold value of Si was then used to determine the possible volumetric energy densities of LIBs with SCC anode (SCC-LIBs) and the potential improvement over graphite-LIBs. The level of improvement in volumetric and gravimetric energy density of SCC-LIBs with constrained volume is predicted to be less than 10% to ensure the battery has similar power characteristics of graphite-LIBs. PMID:27311811

Contaminant concentration in environmental samples using LIBS and CF-LIBS

NASA Astrophysics Data System (ADS)

Pandhija, S.; Rai, N. K.; Rai, A. K.; Thakur, S. N.

2010-01-01

The present paper deals with the detection and quantification of toxic heavy metals like Cd, Co, Pb, Zn, Cr, etc. in environmental samples by using the technique of laser-induced breakdown spectroscopy (LIBS) and calibration-free LIBS (CF-LIBS). A MATLABTM program has been developed based on the CF-LIBS algorithm given by earlier workers and concentrations of pollutants present in industrial area soil have been determined. LIBS spectra of a number of certified reference soil samples with varying concentrations of toxic elements (Cd, Zn) have been recorded to obtain calibration curves. The concentrations of Cd and Zn in soil samples from the Jajmau area, Kanpur (India) have been determined by using these calibration curves and also by the CF-LIBS approach. Our results clearly demonstrate that the combination of LIBS and CF-LIBS is very useful for the study of pollutants in the environment. Some of the results have also been found to be in good agreement with those of ICP-OES.

Emission Characteristics of Laser-Induced Plasma Using Collinear Long and Short Dual-Pulse Laser-Induced Breakdown Spectroscopy (LIBS).

PubMed

Wang, Zhenzhen; Deguchi, Yoshihiro; Liu, Renwei; Ikutomo, Akihiro; Zhang, Zhenzhen; Chong, Daotong; Yan, Junjie; Liu, Jiping; Shiou, Fang-Jung

2017-09-01

Collinear long and short dual-pulse laser-induced breakdown spectroscopy (DP-LIBS) was employed to clarify the emission characteristics from laser-induced plasma. The plasma was sustained and became stable by the long pulse-width laser with the pulse width of 60 μs under free running (FR) conditions as an external energy source. Comparing the measurement results of stainless steel in air using single-pulse LIBS (SP-LIBS) and DP-LIBS, the emission intensity was markedly enhanced using DP-LIBS. The temperature of plasma induced by DP-LIBS was maintained at a higher temperature under different gate delay time and short pulse-width laser power conditions compared with those measured using short SP-LIBS. Moreover, the variation rates of plasma temperatures measured using DP-LIBS were also lower. The superior detection ability was verified by the measurement of aluminum sample in water. The spectra were clearly detected using DP-LIBS, whereas it cannot be identified using SP-LIBS of short and long pulse widths. The effects of gate delay time and short pulse-width laser power were also discussed. These results demonstrate the feasibility and enhanced detection ability of the proposed collinear long and short DP-LIBS method.

Leptin Levels Are Higher in Whole Compared to Skim Human Milk, Supporting a Cellular Contribution

PubMed Central

Kugananthan, Sambavi; Lai, Ching Tat; Gridneva, Zoya; Mark, Peter J.; Geddes, Donna T.; Kakulas, Foteini

2016-01-01

Human milk (HM) contains a plethora of metabolic hormones, including leptin, which is thought to participate in the regulation of the appetite of the developing infant. Leptin in HM is derived from a combination of de novo mammary synthesis and transfer from the maternal serum. Moreover, leptin is partially lipophilic and is also present in HM cells. However, leptin has predominately been measured in skim HM, which contains neither fat nor cells. We optimised an enzyme-linked immunosorbent assay for leptin measurement in both whole and skim HM and compared leptin levels between both HM preparations collected from 61 lactating mothers. Whole HM leptin ranged from 0.2 to 1.47 ng/mL, whilst skim HM leptin ranged from 0.19 to 0.9 ng/mL. Whole HM contained, on average, 0.24 ± 0.01 ng/mL more leptin than skim HM (p < 0.0001, n = 287). No association was found between whole HM leptin and fat content (p = 0.17, n = 287), supporting a cellular contribution to HM leptin. No difference was found between pre- and post-feed samples (whole HM: p = 0.29, skim HM: p = 0.89). These findings highlight the importance of optimising HM leptin measurement and assaying it in whole HM to accurately examine the amount of leptin received by the infant during breastfeeding. PMID:27834797

Leptin Levels Are Higher in Whole Compared to Skim Human Milk, Supporting a Cellular Contribution.

PubMed

Kugananthan, Sambavi; Lai, Ching Tat; Gridneva, Zoya; Mark, Peter J; Geddes, Donna T; Kakulas, Foteini

2016-11-08

Human milk (HM) contains a plethora of metabolic hormones, including leptin, which is thought to participate in the regulation of the appetite of the developing infant. Leptin in HM is derived from a combination of de novo mammary synthesis and transfer from the maternal serum. Moreover, leptin is partially lipophilic and is also present in HM cells. However, leptin has predominately been measured in skim HM, which contains neither fat nor cells. We optimised an enzyme-linked immunosorbent assay for leptin measurement in both whole and skim HM and compared leptin levels between both HM preparations collected from 61 lactating mothers. Whole HM leptin ranged from 0.2 to 1.47 ng/mL, whilst skim HM leptin ranged from 0.19 to 0.9 ng/mL. Whole HM contained, on average, 0.24 ± 0.01 ng/mL more leptin than skim HM ( p < 0.0001, n = 287). No association was found between whole HM leptin and fat content ( p = 0.17, n = 287), supporting a cellular contribution to HM leptin. No difference was found between pre- and post-feed samples (whole HM: p = 0.29, skim HM: p = 0.89). These findings highlight the importance of optimising HM leptin measurement and assaying it in whole HM to accurately examine the amount of leptin received by the infant during breastfeeding.

LibQUAL+[TM]: A Methodological Suite; Reliability and Structure of LibQUAL+[TM] Scores: Measuring Perceived Library Service Quality; Score Norms for Improving Library Service Quality: A LibQUAL+[TM] Study; ARL Index and Other Validity Correlates of LibQUAL+[TM] Scores.

ERIC Educational Resources Information Center

Heath, Fred M.; Thompson, Bruce; Cook, Colleen; Thompson, Russel L.; Kyrillidou, Martha

2002-01-01

Includes four articles that discuss LibQUAL+[TM], a collaborative effort of the Association of Research Libraries and Texas A&M University responding to the need for greater accountability in measuring the delivery of library services to research library users. Discusses the reliability of LibQUAL+[TM] scores in measuring perceived library…

Efficacy and Safety of Peroral Endoscopic Myotomy for Treatment of Achalasia After Failed Heller Myotomy.

PubMed

Ngamruengphong, Saowanee; Inoue, Haruhiro; Ujiki, Michael B; Patel, Lava Y; Bapaye, Amol; Desai, Pankaj N; Dorwat, Shivangi; Nakamura, Jun; Hata, Yoshitaka; Balassone, Valerio; Onimaru, Manabu; Ponchon, Thierry; Pioche, Mathieu; Roman, Sabine; Rivory, Jérôme; Mion, François; Garros, Aurélien; Draganov, Peter V; Perbtani, Yaseen; Abbas, Ali; Pannu, Davinderbir; Yang, Dennis; Perretta, Silvana; Romanelli, John; Desilets, David; Hayee, Bu; Haji, Amyn; Hajiyeva, Gulara; Ismail, Amr; Chen, Yen-I; Bukhari, Majidah; Haito-Chavez, Yamile; Kumbhari, Vivek; Saxena, Payal; Talbot, Michael; Chiu, Philip Wai-Yan; Yip, Hon-Chi; Wong, Vivien Wai-Yin; Hernaez, Ruben; Maselli, Roberta; Repici, Alessandro; Khashab, Mouen A

2017-10-01

In patients with persistent symptoms after Heller myotomy (HM), treatment options include repeat HM, pneumatic dilation, or peroral endoscopic myotomy (POEM). We evaluated the efficacy and safety of POEM in patients with achalasia with prior HM vs without prior HM. We conducted a retrospective cohort study of 180 patients with achalasia who underwent POEM at 13 tertiary centers worldwide, from December 2009 through September 2015. Patients were divided into 2 groups: those with prior HM (HM group, exposure; n = 90) and those without prior HM (non-HM group; n = 90). Clinical response was defined by a decrease in Eckardt scores to 3 or less. Adverse events were graded according to criteria set by the American Society for Gastrointestinal Endoscopy. Technical success, clinical success, and rates of adverse events were compared between groups. Patients were followed up for a median of 8.5 months. POEM was technically successful in 98% of patients in the HM group and in 100% of patients in the non-HM group (P = .49). A significantly lower proportion of patients in the HM group had a clinical response to POEM (81%) than in the non-HM group (94%; P = .01). There were no significant differences in rates of adverse events between the groups (8% in the HM group vs 13% in the non-HM group; P = .23). Symptomatic reflux and reflux esophagitis after POEM were comparable between groups. POEM is safe and effective for patients with achalasia who were not treated successfully by prior HM. Although the rate of clinical success in patients with prior HM is lower than in those without prior HM, the safety profile of POEM is comparable between groups. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

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

Chung, Donald; Elgqvist, Emma; Santhanagopalan, Shriram

Manufacturing capacity for lithium-ion batteries (LIBs)--which power many consumer electronics and are increasingly used to power electric vehicles--is heavily concentrated in east Asia. Currently, China, Japan, and Korea collectively host 88% of all LIB cell and 79% of automotive LIB cell manufacturing capacity. Mature supply chains and strong cumulative production experience suggest that most LIB cell production will remain concentrated in Asia. However, other regions--including North America--could be competitive in the growing automotive LIB cell market under certain conditions. To illuminate the factors that drive regional competitiveness in automotive LIB cell production, this study models cell manufacturing cost and minimummore » sustainable price, and examines development of LIB supply chains and current LIB market conditions. Modeled costs are for large format, 20-Ah stacked pouch cells with lithium-nickel-manganese-cobalt-oxide (NMC) cathodes and graphite anodes suitable for automotive application. Production volume is assumed to be at commercial scale, 600 MWh per year.« less

Comprehensive evaluation of genome-wide 5-hydroxymethylcytosine profiling approaches in human DNA.

PubMed

Skvortsova, Ksenia; Zotenko, Elena; Luu, Phuc-Loi; Gould, Cathryn M; Nair, Shalima S; Clark, Susan J; Stirzaker, Clare

2017-01-01

The discovery that 5-methylcytosine (5mC) can be oxidized to 5-hydroxymethylcytosine (5hmC) by the ten-eleven translocation (TET) proteins has prompted wide interest in the potential role of 5hmC in reshaping the mammalian DNA methylation landscape. The gold-standard bisulphite conversion technologies to study DNA methylation do not distinguish between 5mC and 5hmC. However, new approaches to mapping 5hmC genome-wide have advanced rapidly, although it is unclear how the different methods compare in accurately calling 5hmC. In this study, we provide a comparative analysis on brain DNA using three 5hmC genome-wide approaches, namely whole-genome bisulphite/oxidative bisulphite sequencing (WG Bis/OxBis-seq), Infinium HumanMethylation450 BeadChip arrays coupled with oxidative bisulphite (HM450K Bis/OxBis) and antibody-based immunoprecipitation and sequencing of hydroxymethylated DNA (hMeDIP-seq). We also perform loci-specific TET-assisted bisulphite sequencing (TAB-seq) for validation of candidate regions. We show that whole-genome single-base resolution approaches are advantaged in providing precise 5hmC values but require high sequencing depth to accurately measure 5hmC, as this modification is commonly in low abundance in mammalian cells. HM450K arrays coupled with oxidative bisulphite provide a cost-effective representation of 5hmC distribution, at CpG sites with 5hmC levels >~10%. However, 5hmC analysis is restricted to the genomic location of the probes, which is an important consideration as 5hmC modification is commonly enriched at enhancer elements. Finally, we show that the widely used hMeDIP-seq method provides an efficient genome-wide profile of 5hmC and shows high correlation with WG Bis/OxBis-seq 5hmC distribution in brain DNA. However, in cell line DNA with low levels of 5hmC, hMeDIP-seq-enriched regions are not detected by WG Bis/OxBis or HM450K, either suggesting misinterpretation of 5hmC calls by hMeDIP or lack of sensitivity of the latter methods. We highlight both the advantages and caveats of three commonly used genome-wide 5hmC profiling technologies and show that interpretation of 5hmC data can be significantly influenced by the sensitivity of methods used, especially as the levels of 5hmC are low and vary in different cell types and different genomic locations.

On the morphology of the compact dust shell in the symbiotic system HM Sagittae

NASA Astrophysics Data System (ADS)

Sacuto, S.; Chesneau, O.

2009-01-01

Context: The symbiotic system HM Sagittae consists of a Mira star and a secondary White Dwarf component. The dust content of the system was severely affected by the nova outburst in 1975, which is still ongoing. The capabilities of optical interferometry operating in the mid-IR allow us to investigate the current geometry of the dust envelope. Aims: We test our previous spectro-interferometric study of this system with new interferometric configurations, increasing the uv coverage and allowing us to ascertain the appearance of the source between 8 and 13 μm. Methods: We used the MIDI instrument of the VLTI with the unit telescopes (UTs) and auxiliary telescopes (ATs) providing baselines oriented from PA = 42° to 127°. The data are interpreted by means of an elliptical Gaussian model and the spherical radiative transfer code DUSTY. Results: We demonstrate that the data can be reproduced well by an optically thick dust shell of amorphous silicate, typical of those encountered around Mira stars, whose measured dimension increases from 8 to 13 μm. We confirm that the envelope is more extended in a direction perpendicular to the binary axis. The level of elongation increases with wavelength in contrast to our claim in a previous study. Conclusions: The wider uv coverage allows us to deepen our previous investigations of the close circumstellar structure of this object. Based on observations made with the Very Large Telescope Interferometer at Paranal Observatory under programs 075.D-0484, 077.D-0216, and 079.D-0213. Reduced visibilities and differential phases are available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/493/1043

First Detection of the Hatchett-McCray Effect in the High-Mass X-ray Binary

NASA Technical Reports Server (NTRS)

Sonneborn, G.; Iping, R. C.; Kaper, L.; Hammerschiag-Hensberge, G.; Hutchings, J. B.

2004-01-01

The orbital modulation of stellar wind UV resonance line profiles as a result of ionization of the wind by the X-ray source has been observed in the high-mass X-ray binary 4U1700-37/HD 153919 for the first time. Far-UV observations (905-1180 Angstrom, resolution 0.05 Angstroms) were made at the four quadrature points of the binary orbit with the Far Ultraviolet Spectroscopic Explorer (FUSE) in 2003 April and August. The O6.5 laf primary eclipses the X-ray source (neutron star or black hole) with a 3.41-day period. Orbital modulation of the UV resonance lines, resulting from X-ray photoionization of the dense stellar wind, the so-called Hatchett-McCray (HM) effect, was predicted for 4U1700-37/HD153919 (Hatchett 8 McCray 1977, ApJ, 211, 522) but was not seen in N V 1240, Si IV 1400, or C IV 1550 in IUE and HST spectra. The FUSE spectra show that the P V 1118-1128 and S IV 1063-1073 P-Cygni lines appear to vary as expected for the HM effect, weakest at phase 0.5 (X-ray source conjunction) and strongest at phase 0.0 (X-ray source eclipse). The phase modulation of the O VI 1032-1037 lines, however, is opposite to P V and S IV, implying that O VI may be a byproduct of the wind's ionization by the X-ray source. Such variations were not observed in N V, Si IV, and C IV because of their high optical depth. Due to their lower cosmic abundance, the P V and S IV wind lines are unsaturated, making them excellent tracers of the ionization conditions in the O star's wind.

Laser ablation-laser induced breakdown spectroscopy for the measurement of total elemental concentration in soils.

PubMed

Pareja, Jhon; López, Sebastian; Jaramillo, Daniel; Hahn, David W; Molina, Alejandro

2013-04-10

The performances of traditional laser-induced breakdown spectroscopy (LIBS) and laser ablation-LIBS (LA-LIBS) were compared by quantifying the total elemental concentration of potassium in highly heterogeneous solid samples, namely soils. Calibration curves for a set of fifteen samples with a wide range of potassium concentrations were generated. The LA-LIBS approach produced a superior linear response different than the traditional LIBS scheme. The analytical response of LA-LIBS was tested with a large set of different soil samples for the quantification of the total concentration of Fe, Mn, Mg, Ca, Na, and K. Results showed an acceptable linear response for Ca, Fe, Mg, and K while poor signal responses were found for Na and Mn. Signs of remaining matrix effects for the LA-LIBS approach in the case of soil analysis were found and discussed. Finally, some improvements and possibilities for future studies toward quantitative soil analysis with the LA-LIBS technique are suggested.

SeqLib: a C ++ API for rapid BAM manipulation, sequence alignment and sequence assembly

PubMed Central

Wala, Jeremiah; Beroukhim, Rameen

2017-01-01

Abstract We present SeqLib, a C ++ API and command line tool that provides a rapid and user-friendly interface to BAM/SAM/CRAM files, global sequence alignment operations and sequence assembly. Four C libraries perform core operations in SeqLib: HTSlib for BAM access, BWA-MEM and BLAT for sequence alignment and Fermi for error correction and sequence assembly. Benchmarking indicates that SeqLib has lower CPU and memory requirements than leading C ++ sequence analysis APIs. We demonstrate an example of how minimal SeqLib code can extract, error-correct and assemble reads from a CRAM file and then align with BWA-MEM. SeqLib also provides additional capabilities, including chromosome-aware interval queries and read plotting. Command line tools are available for performing integrated error correction, micro-assemblies and alignment. Availability and Implementation: SeqLib is available on Linux and OSX for the C ++98 standard and later at github.com/walaj/SeqLib. SeqLib is released under the Apache2 license. Additional capabilities for BLAT alignment are available under the BLAT license. Contact: jwala@broadinstitue.org; rameen@broadinstitute.org PMID:28011768

SeqLib: a C ++ API for rapid BAM manipulation, sequence alignment and sequence assembly.

PubMed

Wala, Jeremiah; Beroukhim, Rameen

2017-03-01

We present SeqLib, a C ++ API and command line tool that provides a rapid and user-friendly interface to BAM/SAM/CRAM files, global sequence alignment operations and sequence assembly. Four C libraries perform core operations in SeqLib: HTSlib for BAM access, BWA-MEM and BLAT for sequence alignment and Fermi for error correction and sequence assembly. Benchmarking indicates that SeqLib has lower CPU and memory requirements than leading C ++ sequence analysis APIs. We demonstrate an example of how minimal SeqLib code can extract, error-correct and assemble reads from a CRAM file and then align with BWA-MEM. SeqLib also provides additional capabilities, including chromosome-aware interval queries and read plotting. Command line tools are available for performing integrated error correction, micro-assemblies and alignment. SeqLib is available on Linux and OSX for the C ++98 standard and later at github.com/walaj/SeqLib. SeqLib is released under the Apache2 license. Additional capabilities for BLAT alignment are available under the BLAT license. jwala@broadinstitue.org ; rameen@broadinstitute.org. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

[Rapid measurement of trace mercury in aqueous solutions with optical-electrical dual pulse LIBS technique].

PubMed

Zhang, Qian; Xiong, Wei; Chen, Yu-Qi; Li, Run-Hua

2011-02-01

A wood slice was used as absorber to transfer liquid sample to solid sample in order to solve the problems existing in directly analyzing aqueous solutions with laser-induced breakdown spectroscopy (LIBS). An optical-electrical dual pulse LIBS (OEDP-LIBS) technique was first used to enhance atomic emission of mercury in laser-induced plasma. The calibration curves of mercury were obtained by typical single pulse LIBS and OEDP-LIBS techniques. The limit of detection (LOD) of mercury in these two techniques reaches 2.4 and 0.3 mg x L(-1), respectively. Under current experimental conditions, the time-integrated a tomic emission of mercury at 253.65 nm was enhanced 50 times and the LOD of mercury was improved by one order, if comparing OEDP-LIBS to single pulse LIBS. The required time for a whole analysis process is less than 5 minutes. As the atomic emission of mercury decays slowly while increasing the delay time between electrical pulse and laser pulse, increasing the electrical pulse width can further enhance the time integrated intensity of mercury emission and improve the detection sensitivity of mercury by OEDP-LIBS technique.

Herbal Medicines: challenges in the modern world. Part 5. status and current directions of complementary and alternative herbal medicine worldwide.

PubMed

Enioutina, Elena Yu; Salis, Emma R; Job, Kathleen M; Gubarev, Michael I; Krepkova, Lubov V; Sherwin, Catherine M T

2017-03-01

Herbal medicine (HM) use is growing worldwide. Single herb preparations, ethnic and modern HM formulations are widely used as adjunct therapies or to improve consumer wellbeing. Areas covered: This final part in the publication series summarizes common tendencies in HM use as adjunct or alternative medicine, education of healthcare professionals and consumers, current and proposed guidelines regulating of production. We discuss potential HM-HM and HM-drug interactions that could lead to severe adverse events in situations where HMs are taken without proper medical professional oversight. Expert commentary: A number of serious problems have arisen with the steady global increase in HM use. HM interaction with conventional drugs (CD) may result in inadequate dosing of CD or adverse reactions; HM-HM interaction within herbal supplements could lead to toxicity of formulations. Inadequate education of clinicians and patients regarding medicinal properties of HMs must be addressed regionally and globally to ensure consumer safety.

Essential role of the HMG domain in the function of yeast mitochondrial histone HM: functional complementation of HM by the nuclear nonhistone protein NHP6A.

PubMed

Kao, L R; Megraw, T L; Chae, C B

1993-06-15

The yeast mitochondrial histone protein HM is required for maintenance of the mitochondrial genome, and disruption of the gene encoding HM (HIM1/ABF2) results in formation of a respiration-deficient petite mutant phenotype. HM contains two homologous regions, which share sequence similarity with the eukaryotic nuclear nonhistone protein, HMG-1. Experiments with various deletion mutants of HM show that a single HMG domain of HM is functional and can restore respiration competency to cells that lack HM protein (him1 mutant cells). The gene encoding the putative yeast nuclear HMG-1 homolog, the NHP6A protein, can functionally complement the him1 mutation. These results suggest that the HMG domain is the basic unit for the function of HM in mitochondria and that the function of HMG-1 proteins in the nucleus and HM in the mitochondrion may be equivalent.

[Evaluation of crossing calibration of (123)I-MIBG H/M ration, with the IDW scatter correction method, on different gamma camera systems].

PubMed

Kittaka, Daisuke; Takase, Tadashi; Akiyama, Masayuki; Nakazawa, Yasuo; Shinozuka, Akira; Shirai, Muneaki

2011-01-01

(123)I-MIBG Heart-to-Mediastinum activity ratio (H/M) is commonly used as an indicator of relative myocardial (123)I-MIBG uptake. H/M ratios reflect myocardial sympathetic nerve function, therefore it is a useful parameter to assess regional myocardial sympathetic denervation in various cardiac diseases. However, H/M ratio values differ by site, gamma camera system, position and size of region of interest (ROI), and collimator. In addition to these factors, 529 keV scatter component may also affect (123)I-MIBG H/M ratio. In this study, we examined whether the H/M ratio shows correlation between two different gamma camera systems and that sought for H/M ratio calculation formula. Moreover, we assessed the feasibility of (123)I Dual Window (IDW) method, which is a scatter correction method, and compared H/M ratios with and without IDW method. H/M ratio displayed a good correlation between two gamma camera systems. Additionally, we were able to create a new H/M calculation formula. These results indicated that the IDW method is a useful scatter correction method for calculating (123)I-MIBG H/M ratios.

Expanding Library Services and Instruction Through LibGuides.

PubMed

Ream, Tim; Parker-Kelly, Darlene

2016-01-01

Beginning in 2012, the Charles R. Drew University (CDU) Health Sciences Library used LibGuides in a number of innovative ways. Librarians constructed e-book databases, in-depth tutorials on technology-related topics, and web pages highlighting special events. To assess similar LibGuides innovation, CDU librarians developed an eight-question survey distributed to health sciences and hospital libraries throughout Southern California and Arizona. Results showed that libraries used LibGuides primarily to deliver access to online resources and to provide supplementary materials supporting instruction. Responses also revealed that many libraries had not yet adopted LibGuides. These findings were analyzed and compared to past and current LibGuides design at CDU.

The Role of Sub- and Supercritical CO2 as "Processing Solvent" for the Recycling and Sample Preparation of Lithium Ion Battery Electrolytes.

PubMed

Nowak, Sascha; Winter, Martin

2017-03-06

Quantitative electrolyte extraction from lithium ion batteries (LIB) is of great interest for recycling processes. Following the generally valid EU legal guidelines for the recycling of batteries, 50 wt % of a LIB cell has to be recovered, which cannot be achieved without the electrolyte; hence, the electrolyte represents a target component for the recycling of LIBs. Additionally, fluoride or fluorinated compounds, as inevitably present in LIB electrolytes, can hamper or even damage recycling processes in industry and have to be removed from the solid LIB parts, as well. Finally, extraction is a necessary tool for LIB electrolyte aging analysis as well as for post-mortem investigations in general, because a qualitative overview can already be achieved after a few minutes of extraction for well-aged, apparently "dry" LIB cells, where the electrolyte is deeply penetrated or even gellified in the solid battery materials.

Questioning LibQUAL+[TM]: Expanding Its Assessment of Academic Library Effectiveness

ERIC Educational Resources Information Center

Edgar, William B.

2006-01-01

This article examines LibQUAL+[TM]'s instrument, fundamental assumption, and research approach and proposes a functional/technical model of academic library effectiveness. This expanded view of library effectiveness complements LibQUAL+[TM], emphasizing it to be dependent upon users' experience of service delivery, as LibQUAL+[TM] recognizes.…

Enhancement and stabilization of plasma using collinear long-short double-pulse laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Cui, Minchao; Deguchi, Yoshihiro; Wang, Zhenzhen; Fujita, Yuki; Liu, Renwei; Shiou, Fang-Jung; Zhao, Shengdun

2018-04-01

A collinear long-short dual-pulse laser-induced breakdown spectroscopy (DP-LIBS) method was employed to enhance and stabilize the laser-induced plasma from steel sample. The long-pulse-width laser beam with the pulse width of 60 μs was generated by a Nd: YAG laser which was operated at FR (free running) mode. The comparative experiments were carried out between single pulse LIBS (SP-LIBS) and long-short DP-LIBS. The recorded results showed that the emission intensities and the temperature of plasma were enhanced by long-short DP-LIBS. The plasma images showed that the plasma was bigger and had a longer lifetime in long-short DP-LIBS situation. Through the calculation of time-resolved plasma temperature and intensity ratio, it can be concluded that the plasma was stabilized by the long-pulse-width laser beam. The long-short DP-LIBS method also generated the stable plasma condition from the samples with different initial temperatures, which overcame the difficulties of LIBS in the online measurement for steel production line.

A review on management of spent lithium ion batteries and strategy for resource recycling of all components from them.

PubMed

Zhang, Wenxuan; Xu, Chengjian; He, Wenzhi; Li, Guangming; Huang, Juwen

2018-02-01

The wide use of lithium ion batteries (LIBs) has brought great numbers of discarded LIBs, which has become a common problem facing the world. In view of the deleterious effects of spent LIBs on the environment and the contained valuable materials that can be reused, much effort in many countries has been made to manage waste LIBs, and many technologies have been developed to recycle waste LIBs and eliminate environmental risks. As a review article, this paper introduces the situation of waste LIB management in some developed countries and in China, and reviews separation technologies of electrode components and refining technologies of LiCoO 2 and graphite. Based on the analysis of these recycling technologies and the structure and components characteristics of the whole LIB, this paper presents a recycling strategy for all components from obsolete LIBs, including discharge, dismantling, and classification, separation of electrode components and refining of LiCoO 2 /graphite. This paper is intended to provide a valuable reference for the management, scientific research, and industrial implementation on spent LIBs recycling, to recycle all valuable components and reduce the environmental pollution, so as to realize the win-win situation of economic and environmental benefits.

Combining Raman and laser induced breakdown spectroscopy by double pulse lasing.

PubMed

Lednev, Vasily N; Pershin, Sergey M; Sdvizhenskii, Pavel A; Grishin, Mikhail Ya; Fedorov, Alexander N; Bukin, Vladimir V; Oshurko, Vadim B; Shchegolikhin, Alexander N

2018-01-01

A new approach combining Raman spectrometry and laser induced breakdown spectrometry (LIBS) within a single laser event was suggested. A pulsed solid state Nd:YAG laser running in double pulse mode (two frequency-doubled sequential nanosecond laser pulses with dozens microseconds delay) was used to combine two spectrometry methods within a single instrument (Raman/LIBS spectrometer). First, a low-energy laser pulse (power density far below ablation threshold) was used for Raman measurements while a second powerful laser pulse created the plasma suitable for LIBS analysis. A short time delay between two successive pulses allows measuring LIBS and Raman spectra at different moments but within a single laser flash-lamp pumping. Principal advantages of the developed instrument include high quality Raman/LIBS spectra acquisition (due to optimal gating for Raman/LIBS independently) and absence of target thermal alteration during Raman measurements. A series of high quality Raman and LIBS spectra were acquired for inorganic salts (gypsum, anhydrite) as well as for pharmaceutical samples (acetylsalicylic acid). To the best of our knowledge, the quantitative analysis feasibility by combined Raman/LIBS instrument was demonstrated for the first time by calibration curves construction for acetylsalicylic acid (Raman) and copper (LIBS) in gypsum matrix. Combining ablation pulses and Raman measurements (LIBS/Raman measurements) within a single instrument makes it an efficient tool for identification of samples hidden by non-transparent covering or performing depth profiling analysis including remote sensing. Graphical abstract Combining Raman and laser induced breakdown spectroscopy by double pulse lasing.

Comparison of SP-LIBS and DP-LIBS on metal and non-metal testing based on LIBS

NASA Astrophysics Data System (ADS)

Lin, Xiaomei; Sun, Haoran; Lin, Jingjun

2017-10-01

Laser-induced breakdown spectroscopy (LIBS) technology for metal and nonmetallic detection accuracy is the key technology to be solved in LIBS measurement, Due to metal elements and non-metallic elements in the lively, atomic structure and the degree of excitation of the laser are totally different, so the laser induced plasma evolution and spectral intensity are absolutely different. Among the many factors that affect measurement accuracy, the single and double pulse of the laser has a great influence on the measurement accuracy of metal and non-metal, they both have their own advantages, but also have their own shortcomings. In order to compare the effect of SP-LIBS and DP-LIBS on the measurement results of different elements, in this experiment, we put the metal element aluminum and non-metallic element carbon as the sample, the laser energy as a variable, using the high-speed camera shooting SP- LIBS and DP- LIBS plasma images. Using the spectral analyzer to record the spectral intensity of the elements, by calculating the relative RSD of the signal intensity and comparing the spectral intensity and the signal stability for different elements, develop an optimized experimental program. The experimental results show that under the same energy condition, the metal aluminum ion image under the DP- LIBS and the non-metallic carbon ion image under the SP- LIBS are the most suitable images. By considering the stability of the line intensity and the signal stability, we find that the sensitivity and stability of the signal strength of the metal elements under the double pulse are better than that of the single pulse, and for the non-metallic element, the single pulse laser is better than the double pulse.

AD-LIBS: inferring ancestry across hybrid genomes using low-coverage sequence data.

PubMed

Schaefer, Nathan K; Shapiro, Beth; Green, Richard E

2017-04-04

Inferring the ancestry of each region of admixed individuals' genomes is useful in studies ranging from disease gene mapping to speciation genetics. Current methods require high-coverage genotype data and phased reference panels, and are therefore inappropriate for many data sets. We present a software application, AD-LIBS, that uses a hidden Markov model to infer ancestry across hybrid genomes without requiring variant calling or phasing. This approach is useful for non-model organisms and in cases of low-coverage data, such as ancient DNA. We demonstrate the utility of AD-LIBS with synthetic data. We then use AD-LIBS to infer ancestry in two published data sets: European human genomes with Neanderthal ancestry and brown bear genomes with polar bear ancestry. AD-LIBS correctly infers 87-91% of ancestry in simulations and produces ancestry maps that agree with published results and global ancestry estimates in humans. In brown bears, we find more polar bear ancestry than has been published previously, using both AD-LIBS and an existing software application for local ancestry inference, HAPMIX. We validate AD-LIBS polar bear ancestry maps by recovering a geographic signal within bears that mirrors what is seen in SNP data. Finally, we demonstrate that AD-LIBS is more effective than HAPMIX at inferring ancestry when preexisting phased reference data are unavailable and genomes are sequenced to low coverage. AD-LIBS is an effective tool for ancestry inference that can be used even when few individuals are available for comparison or when genomes are sequenced to low coverage. AD-LIBS is therefore likely to be useful in studies of non-model or ancient organisms that lack large amounts of genomic DNA. AD-LIBS can therefore expand the range of studies in which admixture mapping is a viable tool.

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

Han, Bo-Young; Choi, Daewoong; Park, Se Hwan

Korea Atomic Energy Research Institute (KAERI) have been developing the design and deployment methodology of Laser- Induced Breakdown Spectroscopy (LIBS) instrument for safeguards application within the argon hot cell environment at Advanced spent fuel Conditioning Process Facility (ACPF), where ACPF is a facility being refurbished for the laboratory-scaled demonstration of advanced spent fuel conditioning process. LIBS is an analysis technology used to measure the emission spectra of excited elements in the local plasma of a target material induced by a laser. The spectra measured by LIBS are analyzed to verify the quality and quantity of the specific element in themore » target matrix. Recently LIBS has been recognized as a promising technology for safeguards purposes in terms of several advantages including a simple sample preparation and in-situ analysis capability. In particular, a feasibility study of LIBS to remotely monitor the nuclear material in a high radiation environment has been carried out for supporting the IAEA safeguards implementation. Fiber-Optic LIBS (FO-LIBS) deployment was proposed by Applied Photonics Ltd because the use of fiber optics had benefited applications of LIBS by delivering the laser energy to the target and by collecting the plasma light. The design of FO-LIBS instrument for the measurement of actinides in the spent fuel and high temperature molten salt at ACPF had been developed in cooperation with Applied Photonics Ltd. FO-LIBS has some advantages as followings: the detectable plasma light wavelength range is not limited by the optical properties of the thick lead-glass shield window and the potential risk of laser damage to the lead-glass shield window is not considered. The remote LIBS instrument had been installed at ACPF and then the feasibility study for monitoring actinide elements such as uranium, plutonium, and curium in process materials has been carried out. (authors)« less

Inclusion Detection in Aluminum Alloys Via Laser-Induced Breakdown Spectroscopy

NASA Astrophysics Data System (ADS)

Hudson, Shaymus W.; Craparo, Joseph; De Saro, Robert; Apelian, Diran

2018-04-01

Laser-induced breakdown spectroscopy (LIBS) has shown promise as a technique to quickly determine molten metal chemistry in real time. Because of its characteristics, LIBS could also be used as a technique to sense for unwanted inclusions and impurities. Simulated Al2O3 inclusions were added to molten aluminum via a metal-matrix composite. LIBS was performed in situ to determine whether particles could be detected. Outlier analysis on oxygen signal was performed on LIBS data and compared to oxide volume fraction measured through metallography. It was determined that LIBS could differentiate between melts with different amounts of inclusions by monitoring the fluctuations in signal for elements of interest. LIBS shows promise as an enabling tool for monitoring metal cleanliness.

Research progress in Asia on methods of processing laser-induced breakdown spectroscopy data

NASA Astrophysics Data System (ADS)

Guo, Yang-Min; Guo, Lian-Bo; Li, Jia-Ming; Liu, Hong-Di; Zhu, Zhi-Hao; Li, Xiang-You; Lu, Yong-Feng; Zeng, Xiao-Yan

2016-10-01

Laser-induced breakdown spectroscopy (LIBS) has attracted much attention in terms of both scientific research and industrial application. An important branch of LIBS research in Asia, the development of data processing methods for LIBS, is reviewed. First, the basic principle of LIBS and the characteristics of spectral data are briefly introduced. Next, two aspects of research on and problems with data processing methods are described: i) the basic principles of data preprocessing methods are elaborated in detail on the basis of the characteristics of spectral data; ii) the performance of data analysis methods in qualitative and quantitative analysis of LIBS is described. Finally, a direction for future development of data processing methods for LIBS is also proposed.

Distribution and features of hematological malignancies in Eastern Morocco: a retrospective multicenter study over 5 years.

PubMed

Elidrissi Errahhali, Mounia; Elidrissi Errahhali, Manal; Boulouiz, Redouane; Ouarzane, Meryem; Bellaoui, Mohammed

2016-02-25

Hematological malignancies (HM) are a public health problem. The pattern and distribution of diagnosed hematological cancers vary depending on age, sex, geography, and ethnicity suggesting the involvement of genetic and environmental factors for the development of these diseases. To our knowledge, there is no published report on HM in the case of Eastern Morocco. In this report we present for the first time the overall pattern of HM for this region. Retrospective descriptive study of patients diagnosed with HM between January 2008 and December 2012 in three centres in Eastern Morocco providing cancer diagnosis, treatment or palliative care services. The FAB (French-American-British) classification system has been taken into account in the analysis of myeloid and lymphoid neoplasms. In this study, a total of 660 cases of HM were registered between January 2008 and December 2012. Overall, 6075 cases of cancers all sites combined were registered during this study period, indicating that HM account for around 10.9 % (660/6075) of all cancers recorded. Among the 660 registered cases of HM, 53 % were males and 47 % were females, with a male to female ratio of 1.1. Thus, overall, men are slightly more affected with HM than women. By contrast, a female predominance was observed in the case of Hodgkin's lymphoma (HL), myeloproliferative neoplasms (MPN), acute myeloid leukemia (AML) and the myelodysplastic syndrome (MDS). HM occur at a relatively young age, with an overall median age at diagnosis of 54 years. Non-Hodgkin's lymphoma (NHL) was the most common HM accounting for 29.7 % of all HM, followed by HL, MPN, multiple myelomas (MM), chronic lymphocytic leukemia (CLL), AML, MDS, acute lymphoblastic leukemia (ALL), and Waldenström macroglobulinemia (WM). The majority of HM cases have been observed among patients aged 60 years and over (40.4 % of HM). Among this age group, NHL was the most common HM. In adolescents, HL was the most frequent HM. This study provided for the first time the pattern and distribution of HM in Eastern Morocco. Our findings justify the need to establish a regional cancer registry as a first step in blood cancer control in Eastern Morocco.

Photoluminescence, chemiluminescence and anodic electrochemiluminescence of hydrazide-modified graphene quantum dots

NASA Astrophysics Data System (ADS)

Dong, Yongqiang; Dai, Ruiping; Dong, Tongqing; Chi, Yuwu; Chen, Guonan

2014-09-01

Single-layer graphene quantum dots (SGQDs) were refluxed with hydrazine (N2H4) to prepare hydrazide-modified SGQDs (HM-SGQDs). Compared with SGQDs, partial oxygen-containing groups have been removed from HM-SGQDs. At the same time, a lot of hydrazide groups have been introduced into HM-SGQDs. The introduced hydrazide groups provide HM-SGQDs with a new kind of surface state, and give HM-SGQDs unique photoluminescence (PL) properties such as blue-shifted PL emission and a relatively high PL quantum yield. More importantly, the hydrazide-modification made HM-SGQDs have abundant luminol-like units. Accordingly, HM-SGQDs exhibit unique and excellent chemiluminescence (CL) and anodic electrochemiluminescence (ECL). The hydrazide groups of HM-SGQDs can be chemically oxidized by the dissolved oxygen (O2) in alkaline solutions, producing a strong CL signal. The CL intensity is mainly dependent on the pH value and the concentration of O2, implying the potential applications of HM-SGQDs in pH and O2 sensors. The hydrazide groups of HM-SGQDs can also be electrochemically oxidized in alkaline solutions, producing a strong anodic ECL signal. The ECL intensity can be enhanced sensitively by hydrogen peroxide (H2O2). The enhanced ECL intensity is proportional to the concentration of H2O2 in a wide range of 3 μM to 500 μM. The detection limit of H2O2 was calculated to be about 0.7 μM. The results suggest the great potential applications of HM-SGQDs in the sensors of H2O2 and bio-molecules that are able to produce H2O2 in the presence of enzymes.Single-layer graphene quantum dots (SGQDs) were refluxed with hydrazine (N2H4) to prepare hydrazide-modified SGQDs (HM-SGQDs). Compared with SGQDs, partial oxygen-containing groups have been removed from HM-SGQDs. At the same time, a lot of hydrazide groups have been introduced into HM-SGQDs. The introduced hydrazide groups provide HM-SGQDs with a new kind of surface state, and give HM-SGQDs unique photoluminescence (PL) properties such as blue-shifted PL emission and a relatively high PL quantum yield. More importantly, the hydrazide-modification made HM-SGQDs have abundant luminol-like units. Accordingly, HM-SGQDs exhibit unique and excellent chemiluminescence (CL) and anodic electrochemiluminescence (ECL). The hydrazide groups of HM-SGQDs can be chemically oxidized by the dissolved oxygen (O2) in alkaline solutions, producing a strong CL signal. The CL intensity is mainly dependent on the pH value and the concentration of O2, implying the potential applications of HM-SGQDs in pH and O2 sensors. The hydrazide groups of HM-SGQDs can also be electrochemically oxidized in alkaline solutions, producing a strong anodic ECL signal. The ECL intensity can be enhanced sensitively by hydrogen peroxide (H2O2). The enhanced ECL intensity is proportional to the concentration of H2O2 in a wide range of 3 μM to 500 μM. The detection limit of H2O2 was calculated to be about 0.7 μM. The results suggest the great potential applications of HM-SGQDs in the sensors of H2O2 and bio-molecules that are able to produce H2O2 in the presence of enzymes. Electronic supplementary information (ESI) available: AFM images of SGQDs and HM-SGQDs (Fig. S1), FT-IR spectra of SGQDs and HM-SGQDs (Fig. S2), UV-vis and PL emission spectra of R-SGQDs (Fig. S3), cathodic ECL responses of SGQD, R-SGQDs and HM-SGQDs (Fig. S4), and the pH effect on the anodic ECL responses of HM-SGQDs (Fig. S5). See DOI: 10.1039/c4nr02539c

Laser-induced breakdown spectroscopy (LIBS), part II: review of instrumental and methodological approaches to material analysis and applications to different fields.

PubMed

Hahn, David W; Omenetto, Nicoló

2012-04-01

The first part of this two-part review focused on the fundamental and diagnostics aspects of laser-induced plasmas, only touching briefly upon concepts such as sensitivity and detection limits and largely omitting any discussion of the vast panorama of the practical applications of the technique. Clearly a true LIBS community has emerged, which promises to quicken the pace of LIBS developments, applications, and implementations. With this second part, a more applied flavor is taken, and its intended goal is summarizing the current state-of-the-art of analytical LIBS, providing a contemporary snapshot of LIBS applications, and highlighting new directions in laser-induced breakdown spectroscopy, such as novel approaches, instrumental developments, and advanced use of chemometric tools. More specifically, we discuss instrumental and analytical approaches (e.g., double- and multi-pulse LIBS to improve the sensitivity), calibration-free approaches, hyphenated approaches in which techniques such as Raman and fluorescence are coupled with LIBS to increase sensitivity and information power, resonantly enhanced LIBS approaches, signal processing and optimization (e.g., signal-to-noise analysis), and finally applications. An attempt is made to provide an updated view of the role played by LIBS in the various fields, with emphasis on applications considered to be unique. We finally try to assess where LIBS is going as an analytical field, where in our opinion it should go, and what should still be done for consolidating the technique as a mature method of chemical analysis. © 2012 Society for Applied Spectroscopy

Biomedical applications of laser-induced breakdown spectroscopy (LIBS)

NASA Astrophysics Data System (ADS)

Unnikrishnan, V. K.; Nayak, Rajesh; Bhat, Sujatha; Mathew, Stanley; Kartha, V. B.; Santhosh, C.

2015-03-01

LIBS has been proven to be a robust elemental analysis tool attracting interest because of the wide applications. LIBS can be used for analysis of any type of samples i.e. environmental/physiological, regardless of its state of matter. Conventional spectroscopy techniques are good in analytical performance, but their sample preparation method is mostly destructive and time consuming. Also, almost all these methods are incapable of analysing multi elements simaltaneously. On the other hand, LIBS has many potential advantages such as simplicity in the experimental setup, less sample preparation, less destructive analysis of sample etc. In this paper, we report some of the biomedical applications of LIBS. From the experiments carried out on clinical samples (calcified tissues or teeth and gall stones) for trace elemental mapping and detection, it was found that LIBS is a robust tool for such applications. It is seen that the presence and relative concentrations of major elements (calcium, phosphorus and magnesium) in human calcified tissue (tooth) can be easily determined using LIBS technique. The importance of this study comes in anthropology where tooth and bone are main samples from which reliable data can be easily retrieved. Similarly, elemental composition of bile juice and gall stone collected from the same subject using LIBS was found to be similar. The results show interesting prospects for LIBS to study cholelithiasis (the presence of stones in the gall bladder, is a common disease of the gastrointestinal tract) better.

A Simple LIBS (Laser-Induced Breakdown Spectroscopy) Laboratory Experiment to Introduce Undergraduates to Calibration Functions and Atomic Spectroscopy

ERIC Educational Resources Information Center

Chinni, Rosemarie C.

2012-01-01

This laboratory experiment introduces students to a different type of atomic spectroscopy: laser-induced breakdown spectroscopy (LIBS). LIBS uses a laser-generated spark to excite the sample; once excited, the elemental emission is spectrally resolved and detected. The students use LIBS to analyze a series of standard synthetic silicate samples…

Concurrent Validity of LibQUAL+[TM] Scores: What Do LibQUAL+[TM] Scores Measure?

ERIC Educational Resources Information Center

Thompson, Bruce; Cook, Colleen; Kyrillidou, Martha

2005-01-01

The present study investigated the validity of LibQUAL+[TM] scores, and specifically how total and subscale LibQUAL+[TM] scores are associated with self-reported, library-related satisfaction and outcomes scores. Participants included 88,664 students and faculty who completed the American English (n[AE] = 69,494) or the British English (n[BE] =…

[Dynamics of ecological footprints of agricultural region in Hexi oasis of Gansu Province].

PubMed

Lin, Haiming; Xie, Peng

2004-05-01

This paper studied the dynamics of ecological footprints (EF), degree of sustainable development and its tendency of Hexi oasis agricultural region in Gansu. The results showed that the EF displayed an increasing trend from 0.426 hm2 to 2.158 hm2 in 1949-2000, which was 0.693 hm2 in 1949-1970, 1.029 hm2 in 1975-1980, and 2.288 hm2 in 1985-2000. The ecological capacity (EC) was also increased from 0.550 hm2 in 1949 to 1.762 hm2 in 2000. Comparing with EF, the EC increased at low speed, which reached 0.782 hm2 in 1949-1970 and 1.715 hm2 in 1975-2000. Meanwhile, the sustainable development of Hexi region maintained ecological remainder during 1949-1975. However, it emerged ecological deficit in 1980, and resumed in 1985. The sustainable development of Hexi region has been successive ecological deficit since 1991. The degree was keeping negative increment at acceleration, and got to -0258 hm2 in 1991-2000. These results showed that the regional economic development of Hexi region was far away from sustainable development, and was in no-sustainable state.

Automatic remote monitoring utilizing daily transmissions: transmission reliability and implantable cardioverter defibrillator battery longevity in the TRUST trial.

PubMed

Varma, Niraj; Love, Charles J; Schweikert, Robert; Moll, Philip; Michalski, Justin; Epstein, Andrew E

2018-04-01

Benefits of automatic remote home monitoring (HM) among implantable cardioverter defibrillator (ICD) patients may require high transmission frequency. However, transmission reliability and effects on battery longevity remain uncertain. We hypothesized that HM would have high transmission success permitting punctual guideline based follow-up, and improve battery longevity. This was tested in the prospective randomized TRUST trial. Implantable cardioverter defibrillator patients were randomized post-implant 2:1 to HM (n = 908) (transmit daily) or to Conventional in-person monitoring [conventional management (CM), n = 431 (HM disabled)]. In both groups, five evaluations were scheduled every 3 months for 15 months. Home Monitoring technology performance was assessed by transmissions received vs. total possible, and number of scheduled HM checks failing because of missed transmissions. Battery longevity was compared in HM vs. CM at 15 months, and again in HM 3 years post-implant using continuously transmitted data. Transmission success per patient was 91% (median follow-up of 434 days). Overall, daily HM transmissions were received in 315 795 of a potential 363 450 days (87%). Only 55/3759 (1.46%) of unsuccessful scheduled evaluations in HM were attributed to transmission loss. Shock frequency and pacing percentage were similar in HM vs. CM. Fifteen month battery longevity was 12% greater in HM (93.2 ± 8.8% vs. 83.5 ± 6.0% CM, P < 0.001). In extended follow-up of HM patients, estimated battery longevity was 50.9 ± 9.1% (median 52%) at 36 months. Automatic remote HM demonstrated robust transmission reliability. Daily transmission load may be sustained without reducing battery longevity. Home Monitoring conserves battery longevity and tracks long term device performance. ClinicalTrials.gov; NCT00336284.

Study of archaeological coins of different dynasties using libs coupled with multivariate analysis

NASA Astrophysics Data System (ADS)

Awasthi, Shikha; Kumar, Rohit; Rai, G. K.; Rai, A. K.

2016-04-01

Laser Induced Breakdown Spectroscopy (LIBS) is an atomic emission spectroscopic technique having unique capability of an in-situ monitoring tool for detection and quantification of elements present in different artifacts. Archaeological coins collected form G.R. Sharma Memorial Museum; University of Allahabad, India has been analyzed using LIBS technique. These coins were obtained from excavation of Kausambi, Uttar Pradesh, India. LIBS system assembled in the laboratory (laser Nd:YAG 532 nm, 4 ns pulse width FWHM with Ocean Optics LIBS 2000+ spectrometer) is employed for spectral acquisition. The spectral lines of Ag, Cu, Ca, Sn, Si, Fe and Mg are identified in the LIBS spectra of different coins. LIBS along with Multivariate Analysis play an effective role for classification and contribution of spectral lines in different coins. The discrimination between five coins with Archaeological interest has been carried out using Principal Component Analysis (PCA). The results show the potential relevancy of the methodology used in the elemental identification and classification of artifacts with high accuracy and robustness.

Rational material design for ultrafast rechargeable lithium-ion batteries.

PubMed

Tang, Yuxin; Zhang, Yanyan; Li, Wenlong; Ma, Bing; Chen, Xiaodong

2015-10-07

Rechargeable lithium-ion batteries (LIBs) are important electrochemical energy storage devices for consumer electronics and emerging electrical/hybrid vehicles. However, one of the formidable challenges is to develop ultrafast charging LIBs with the rate capability at least one order of magnitude (>10 C) higher than that of the currently commercialized LIBs. This tutorial review presents the state-of-the-art developments in ultrafast charging LIBs by the rational design of materials. First of all, fundamental electrochemistry and related ionic/electronic conduction theories identify that the rate capability of LIBs is kinetically limited by the sluggish solid-state diffusion process in electrode materials. Then, several aspects of the intrinsic materials, materials engineering and processing, and electrode materials architecture design towards maximizing both ionic and electronic conductivity in the electrode with a short diffusion length are deliberated. Finally, the future trends and perspectives for the ultrafast rechargeable LIBs are discussed. Continuous rapid progress in this area is essential and urgent to endow LIBs with ultrafast charging capability to meet huge demands in the near future.

Combined raman spectrometer/laser-induced breakdown spectrometer design concept

NASA Astrophysics Data System (ADS)

Bazalgette Courrèges-Lacoste, Gregory; Ahlers, Berit; Boslooper, Erik; Rull-Perez, Fernando; Maurice, Sylvestre

2017-11-01

Amongst the different instruments that have been preselected to be on-board the Pasteur payload on ExoMars is the Raman/ Laser Induced Breakdown Spectroscopy (LIBS) instrument. Raman spectroscopy and LIBS will be integrated into a single instrument sharing many hardware commonalities. An international team under the lead of TNO has been gathered to produce a design concept for a combined Raman Spectrometer/ LIBS Elegant Bread-Board (EBB). The instrument is based on a specifically designed extremely compact spectrometer with high resolution over a large wavelength range, suitable for both Raman spectroscopy and LIBS measurements. Low mass, size and resources are the main drivers of the instrument's design concept. The proposed design concept, realization and testing programme for the combined Raman/ LIBS EBB is presented as well as background information on Raman and LIBS.

The high-osmolarity glycerol- and cell wall integrity-MAP kinase pathways of Saccharomyces cerevisiae are involved in adaptation to the action of killer toxin HM-1.

PubMed

Miyamoto, Masahiko; Furuichi, Yasuhiro; Komiyama, Tadazumi

2012-11-01

Fps1p is an aquaglyceroporin important for turgor regulation of Saccharomyces cerevisiae. Previously we reported the involvement of Fps1p in the yeast-killing action of killer toxin HM-1. The fps1 cells showed a high HM-1-resistant phenotype in hypotonic medium and an HM-1-susceptible phenotype in hypertonic medium. This osmotic dependency in HM-1 susceptibility was similar to those observed in Congo red, but different from those observed in other cell wall-disturbing agents. These results indicate that HM-1 exerts fungicidal activity mainly by binding and inserting into the yeast cell wall structure, rather than by inhibiting 1,3-β-glucan synthase. We next determined HM-1-susceptibility and diphospho-MAP kinase inductions in S. cerevisiae. In the wild-type cell, expressions of diphospho-Hog1p and -Slt2p, and mRNA transcription of CWP1 and HOR2, were induced within 1 h after an addition of HM-1. ssk1 and pbs2 cells, but not sho1 and hkr1 cells, showed HM-1-sensitive phenotypes and lacked inductions of phospho-Hog1p in response to HM-1. mid2, rom2 and bck1 cells showed HM-1-sensitive phenotypes and decreased inductions of phospho-Slt2p in response to HM-1. From these results, we postulated that the Sln1-Ypd1-Ssk1 branch of the high-osmolality glycerol (HOG) pathway and plasma membrane sensors of the cell wall integrity (CWI) pathway detect cell wall stresses caused by HM-1. We further suggested that activations of both HOG and CWI pathways have an important role in the adaptive response to HM-1 toxicity. Copyright © 2012 John Wiley & Sons, Ltd.

Effect of daily remote monitoring on pacemaker longevity: a retrospective analysis.

PubMed

Ricci, Renato Pietro; Morichelli, Loredana; Quarta, Laura; Porfili, Antonio; Magris, Barbara; Giovene, Lisa; Torcinaro, Sergio; Gargaro, Alessio

2015-02-01

Energy demand of remote monitoring in cardiac implantable electronic devices has never been investigated. Biotronik Home Monitoring (HM) is characterized by daily transmissions that may affect longevity. The aim of the study was to retrospectively compare longevity of a specific dual-chamber pacemaker model in patients with HM on and patients with HM off. Hospital files of 201 patients (mean age 87 ± 10 years, 78 men) who had received a Biotronik Cylos DR-T pacemaker between April 2006 and May 2010 for standard indication were reviewed. In 134 patients (67%), HM was activated. The primary end point was device replacement due to battery depletion. The median follow-up period was 56.4 months (interquartile range 41.8-65.2 months). The estimated device longevity was 71.1 months (95% confidence interval [CI] 69.1-72.3 months) in the HM-on group and 60.4 months (CI 55.9-65.1 months) in the HM-off group (P < .0001). The frequency of inhospital visits with significant device reprogramming was higher in the HM-on group than in the HM-off group (33.3% vs 25.0%, respectively; P = .03). Lower ventricular pulse amplitude (2.3 ± 0.4 V vs 2.7 ± 0.5 V; P < .0001) and pacing percentage (49% ± 38% vs 64% ± 38%; P = .02), both calculated as time-weighted averages, were observed with HM on as compared with HM off. Patient attrition was significantly lower in the HM-on group (9.7%; 95% CI 3.0%-28.7%) than in the HM-off group (45.6%; 95% CI 30.3%-64.3%) (P < .0001). In normal practice, energy demand of HM, if present, was overshadowed by programming optimization likely favored by continuous monitoring. Pacemakers controlled remotely with HM showed an 11-month longer longevity. Patient retention was superior. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Pumping human milk in the early postpartum period: its impact on long-term practices for feeding at the breast and exclusively feeding human milk in a longitudinal survey cohort1

PubMed Central

2016-01-01

Background: Most American mothers who feed human milk (HM) now use pumps to produce some of the HM they feed. Pumping is nationally recommended, but associations between pumping and HM-feeding durations are unknown. Objectives: We examined whether and how the pumping frequency and types of reasons for pumping between 1.5 and 4.5 mo postpartum are associated with HM-feeding durations. We classified pumping reasons as nonelective [e.g., because of a difficulty feeding at the breast (FAB)] or elective (e.g., to produce HM to mix with solids). We hypothesized that women who pumped more frequently or nonelectively would have shorter HM-feeding durations. Design: We used data from 1116 mothers in a longitudinal cohort who fed and pumped HM 1.5–4.5 mo postpartum. We used χ2 and Cox proportional hazards regression models to examine the survival of any HM feeding, exclusive HM feeding, and FAB. Results: Compared with mothers who pumped for elective reasons, mothers who reported one nonelective reason had greater hazards of stopping feeding any HM (HR: 1.12; 95% CI: 1.05, 1.21) or exclusive HM (HR: 1.14; 95% CI: 1.09, 1.20) and of stopping FAB (HR: 2.07; 95% CI: 1.77, 2.42). Mothers who pumped most frequently had the highest mean hazards of stopping feeding any HM (HR: 1.82; 95% CI: 1.68, 1.93) and feeding exclusive HM (HR: 1.21; 95% CI: 1.14, 1.26). Hazards of stopping FAB varied across the year. Compared with the least-frequent pumpers, the most-frequent pumpers had a 2.6-fold higher hazard of stopping FAB at 3 mo postpartum and a 1.7-fold higher hazard at 6 mo postpartum. Conclusions: Nonelective pumping reasons and higher pumping frequency were associated with shorter HM-feeding durations. Mothers who report that they use a breast pump for reasons related to either employment or FAB difficulty and their infants may be more vulnerable to risks associated with a shorter HM-feeding duration. PMID:27009751

Pumping human milk in the early postpartum period: its impact on long-term practices for feeding at the breast and exclusively feeding human milk in a longitudinal survey cohort.

PubMed

Felice, Julia P; Cassano, Patricia A; Rasmussen, Kathleen M

2016-05-01

Most American mothers who feed human milk (HM) now use pumps to produce some of the HM they feed. Pumping is nationally recommended, but associations between pumping and HM-feeding durations are unknown. We examined whether and how the pumping frequency and types of reasons for pumping between 1.5 and 4.5 mo postpartum are associated with HM-feeding durations. We classified pumping reasons as nonelective [e.g., because of a difficulty feeding at the breast (FAB)] or elective (e.g., to produce HM to mix with solids). We hypothesized that women who pumped more frequently or nonelectively would have shorter HM-feeding durations. We used data from 1116 mothers in a longitudinal cohort who fed and pumped HM 1.5-4.5 mo postpartum. We used χ(2) and Cox proportional hazards regression models to examine the survival of any HM feeding, exclusive HM feeding, and FAB. Compared with mothers who pumped for elective reasons, mothers who reported one nonelective reason had greater hazards of stopping feeding any HM (HR: 1.12; 95% CI: 1.05, 1.21) or exclusive HM (HR: 1.14; 95% CI: 1.09, 1.20) and of stopping FAB (HR: 2.07; 95% CI: 1.77, 2.42). Mothers who pumped most frequently had the highest mean hazards of stopping feeding any HM (HR: 1.82; 95% CI: 1.68, 1.93) and feeding exclusive HM (HR: 1.21; 95% CI: 1.14, 1.26). Hazards of stopping FAB varied across the year. Compared with the least-frequent pumpers, the most-frequent pumpers had a 2.6-fold higher hazard of stopping FAB at 3 mo postpartum and a 1.7-fold higher hazard at 6 mo postpartum. Nonelective pumping reasons and higher pumping frequency were associated with shorter HM-feeding durations. Mothers who report that they use a breast pump for reasons related to either employment or FAB difficulty and their infants may be more vulnerable to risks associated with a shorter HM-feeding duration. © 2016 American Society for Nutrition.

Getting More Value from the LibQUAL+® Survey: The Merits of Qualitative Analysis and Importance-Satisfaction Matrices in Assessing Library Patron Comments

ERIC Educational Resources Information Center

Detlor, Brian; Ball, Kathryn

2015-01-01

This paper examines the merit of conducting a qualitative analysis of LibQUAL+® survey comments as a means of leveraging quantitative LibQUAL+ results, and using importance-satisfaction matrices to present and assess qualitative findings. Comments collected from the authors' institution's LibQUAL+ survey were analyzed using a codebook based on…

Biosynthesis of gold nanoparticles by actinomycete Streptomyces viridogens strain HM10.

PubMed

Balagurunathan, R; Radhakrishnan, M; Rajendran, R Babu; Velmurugan, D

2011-10-01

Biosynthesis of gold nanoparticles by Streptomycetes from Himalayan Mountain was undertaken for the first time. Out of 10 actinomycete strains tested, four strains (D10, HM10, ANS2 and MSU) showed evidence for the intracellular biosynthesis of gold nanoparticles, among which the strain HM10 showed high potency. Presence of spherical and rod shaped gold nanoparticles in mycelium of the strain HM10 was determined by transmission electron microscopy (TEM) and X-ray diffraction analysis. The average particle size ranged from 18-20 nm. UV spectral analysis indicated that the reduction of chloroauric acid (HAuCl4) occurred within 24 h of reaction period. Further, the strain HM10 showed enhanced growth at 1 and 10 mM concentration of HAuCl4. The gold nanoparticles synthesized by the strain HM10 showed good antibacterial activity against S. aureus and E. coli in well-diffusion method. The potential actinomycete HM10 strain was phenotypically characterized and identified as Streptomyces viridogens (HM10). Thus, actinomycete strain HM10 reported in this study is a newly added source for the biosynthesis of gold nanoparticles.

Recurrent achalasia treated with Heller myotomy: A review of the literature

PubMed Central

Wang, Lan; Li, You-Ming

2008-01-01

AIM: To evaluate the efficacy and safety of Heller myotomy (HM) for recurrent achalasia, performed after different methods of first-line treatment. METHODS: We searched for studies published in PubMed from 1966 to March 2008 on treatment of recurrent achalasia with HM after failure with different methods of first-line treatment. The efficacy of HM was assessed by a pooled estimate of response rate with individual studies weighted proportionally to sample size. RESULTS: Sixteen studies were eligible and included in the review. The results showed that HM has a better remission rate for recurrent achalasia after failure of HM [weighted mean (SD)] of 86.9% (21.8%) compared with 81.6% (23.8%) for pneumatic dilatation (PD). One study evaluated the efficacy of HM after failure of PD combined with botulinum toxin injection (83%). The most common complications were perforation and gastroesophageal reflux. CONCLUSION: HM has the best efficacy in patients with recurrent achalasia who were treated with HM as first-line treatment. Future studies should focus on how to increase the success rate and decrease the complications of HM. PMID:19084921

Calcium, zinc, and iron bioavailabilities from a commercial human milk fortifier: a comparison study.

PubMed

Etcheverry, P; Wallingford, J C; Miller, D D; Glahn, R P

2004-11-01

Adding human milk fortifiers (HMF) to human milk (HM) is one way of overcoming the nutrient deficits found in the latter. In this study, the bioavailabilities of calcium, zinc, and iron in S-26/SMA HMF added to HM were compared with those in HM fortified with various bovine milk proteins: alpha-lactalbumin, colostrum, caseinate, casein phosphopeptides, and whey protein concentrate. The bioavailability of each mineral was assessed using an in vitro digestion/Caco-2 cell culture model. Calcium and zinc uptake by the cells was traced with radioisotopes; iron uptake was assessed via cell ferritin levels. Samples were prepared on an equal protein content basis and with added calcium, but no zinc or iron was added. Results revealed that calcium uptake from HM + S-26/SMA was not different from any of the HM fortified with the bovine milk proteins, except for unfortified HM and HM + colostrum in which calcium uptake was significantly lower (-89 and -38%, respectively). Uptake of zinc and iron were significantly higher for HM + S-26/SMA than for the other HM + fortifiers.

Lessons Learned from LIBS Calibration Development

NASA Astrophysics Data System (ADS)

Dyar, M. D.; Breves, E. A.; Lepore, K. H.; Boucher, T. F.; Giguere, S.

2016-10-01

More than two decades of work have been dedicated to development of robust standards, data processing, and calibration tools for LIBS. Here we summarize major considerations for improving accuracy of LIBS chemical analyses.

Adaptive Multi-sensor Data Fusion Model for In-situ Exploration of Mars

NASA Astrophysics Data System (ADS)

Schneiderman, T.; Sobron, P.

2014-12-01

Laser Raman spectroscopy (LRS) and laser-induced breakdown spectroscopy (LIBS) can be used synergistically to characterize the geochemistry and mineralogy of potential microbial habitats and biosignatures. The value of LRS and LIBS has been recognized by the planetary science community: (i) NASA's Mars2020 mission features a combined LRS-LIBS instrument, SuperCam, and an LRS instrument, SHERLOC; (ii) an LRS instrument, RLS, will fly on ESA's 2018 ExoMars mission. The advantages of combining LRS and LIBS are evident: (1) LRS/LIBS can share hardware components; (2) LIBS reveals the relative concentration of major (and often trace) elements present in a sample; and (3) LRS yields information on the individual mineral species and their chemical/structural nature. Combining data from LRS and LIBS enables definitive mineral phase identification with precise chemical characterization of major, minor, and trace mineral species. New approaches to data processing are needed to analyze large amounts of LRS+LIBS data efficiently and maximize the scientific return of integrated measurements. Multi-sensor data fusion (MSDF) is a method that allows for robust sample identification through automated acquisition, processing, and combination of data. It optimizes information usage, yielding a more robust characterization of a target than could be acquired through single sensor use. We have developed a prototype fuzzy logic adaptive MSDF model aimed towards the unsupervised characterization of Martian habitats and their biosignatures using LRS and LIBS datasets. Our model also incorporates fusion of microimaging (MI) data - critical for placing analyses in geological and spatial context. Here, we discuss the performance of our novel MSDF model and demonstrate that automated quantification of the salt abundance in sulfate/clay/phyllosilicate mixtures is possible through data fusion of collocated LRS, LIBS, and MI data.

Laser-induced breakdown spectroscopy of dental lesions: diagnostic and therapeutic monitoring tool

NASA Astrophysics Data System (ADS)

Borisova, Ekaterina; Uzunov, Tzonko; Penev, Dimitar; Genova, Tsanislava; Avramov, Latchezar

2016-01-01

The carious decay develops a tiny area of demineralization on the enamel, which could be detected by element analytic techniques such as laser-induced breakdown spectroscopy (LIBS). That demineralization can quickly turn into a large lesion inside the tooth, it is often discovered too late to prevent the kind of decay that leads to cavities. The same optical LIBS detection approach could be used for monitoring of the caries removal using laser ablation or drilling techniques. For LIBS measurements we applied LIBS 2500Plus (Ocean Optics Inc., Dunedin, USA) system, which consists of seven spectrometric channels, covering spectral region from 200 to 980 nm, which optical resolution 0,05 nm, the spectrometers are connected with sample fiber bundle for 7-channels spectral system to the chamber for solid and liquid samples, Q-switched Nd:YAG laser, at 1 064 nm, with energy per pulse - 40 mJ, which is applied to induce plasma in the samples. LIBS spectra were obtained after single shot of the laser in the region of pathology. Samples investigated by LIBS are extracted teeth from patients, with periodontal problems on different stage of carious lesions, and their LIBS spectra are compared with the LIBS signals obtained from normal enamel and dentine tissues to receive complete picture of the carious lesion development. The major line of our investigations is related to the development of a methodology for real-time optical feedback control during selective ablation of tooth tissues using LIBS. Tooth structures, with and without pathological changes, are compared and their LIBS element analysis is used to differentiate major changes, which occur during tooth carious process and growth.

Improved intact soil-core carbon determination applying regression shrinkage and variable selection techniques to complete spectrum laser-induced breakdown spectroscopy (LIBS).

PubMed

Bricklemyer, Ross S; Brown, David J; Turk, Philip J; Clegg, Sam M

2013-10-01

Laser-induced breakdown spectroscopy (LIBS) provides a potential method for rapid, in situ soil C measurement. In previous research on the application of LIBS to intact soil cores, we hypothesized that ultraviolet (UV) spectrum LIBS (200-300 nm) might not provide sufficient elemental information to reliably discriminate between soil organic C (SOC) and inorganic C (IC). In this study, using a custom complete spectrum (245-925 nm) core-scanning LIBS instrument, we analyzed 60 intact soil cores from six wheat fields. Predictive multi-response partial least squares (PLS2) models using full and reduced spectrum LIBS were compared for directly determining soil total C (TC), IC, and SOC. Two regression shrinkage and variable selection approaches, the least absolute shrinkage and selection operator (LASSO) and sparse multivariate regression with covariance estimation (MRCE), were tested for soil C predictions and the identification of wavelengths important for soil C prediction. Using complete spectrum LIBS for PLS2 modeling reduced the calibration standard error of prediction (SEP) 15 and 19% for TC and IC, respectively, compared to UV spectrum LIBS. The LASSO and MRCE approaches provided significantly improved calibration accuracy and reduced SEP 32-55% over UV spectrum PLS2 models. We conclude that (1) complete spectrum LIBS is superior to UV spectrum LIBS for predicting soil C for intact soil cores without pretreatment; (2) LASSO and MRCE approaches provide improved calibration prediction accuracy over PLS2 but require additional testing with increased soil and target analyte diversity; and (3) measurement errors associated with analyzing intact cores (e.g., sample density and surface roughness) require further study and quantification.

[Expression and clinical significance of 5hmC in bladder urothelial carcinoma].

PubMed

Li, Jie; Xu, Yuqiao; Zhang, Zhiwen; Zhang, Ming; Zhang, Zhekai; Zhang, Feng; Li, Qing

2016-02-01

To investigate the expression of 5-hydroxymethylcytosine (5hmC) in bladder urothelial carcinoma (UC) and its clinical significance. The expression of 5hmC in 21 cases of UC tissues and pericarcinous urinary tract epithelium was detected by immunohistochemical staining. Then the expression of 5hmC in the surgical resection of UC tissues in 92 cases was also surveyed. Non parametric U Mann-Whitney test was used to analyze the correlation between 5hmC expression and clinical data. Single factor survival analysis was performed by Kaplan-Meier test. The expression of 5hmC in normal urinary tract epithelium and UC tissues was significantly different, but there was no significant difference in the expression of 5hmC between low and high grades of UC tissues as well as between different TNM grades. Kaplan-Meier single factor survival analysis showed that there was no significant correlation between the 5hmC expression level and the survival rate or the recurrence-free survival of UC patients. The expression level of 5hmC in UC tissues is significantly lower than that in pericarcinous urinary tract epithelium. There is no correlation between the 5hmC expression and the progression, prognosis and recurrence of UC.

Mid-infrared, long wave infrared (4-12 μm) molecular emission signatures from pharmaceuticals using laser-induced breakdown spectroscopy (LIBS).

PubMed

Yang, Clayton S-C; Brown, Ei E; Kumi-Barimah, Eric; Hommerich, Uwe H; Jin, Feng; Trivedi, Sudhir B; Samuels, Alan C; Snyder, A Peter

2014-01-01

In an effort to augment the atomic emission spectra of conventional laser-induced breakdown spectroscopy (LIBS) and to provide an increase in selectivity, mid-wave to long-wave infrared (IR), LIBS studies were performed on several organic pharmaceuticals. Laser-induced breakdown spectroscopy signature molecular emissions of target organic compounds are observed for the first time in the IR fingerprint spectral region between 4-12 μm. The IR emission spectra of select organic pharmaceuticals closely correlate with their respective standard Fourier transform infrared spectra. Intact and/or fragment sample molecular species evidently survive the LIBS event. The combination of atomic emission signatures derived from conventional ultraviolet-visible-near-infrared LIBS with fingerprints of intact molecular entities determined from IR LIBS promises to be a powerful tool for chemical detection.

Effect of Atmospheric Conditions on LIBS Spectra

PubMed Central

Effenberger, Andrew J.; Scott, Jill R.

2010-01-01

Laser-induced breakdown spectroscopy (LIBS) is typically performed at ambient Earth atmospheric conditions. However, interest in LIBS in other atmospheric conditions has increased in recent years, especially for use in space exploration (e.g., Mars and Lunar) or to improve resolution for isotopic signatures. This review focuses on what has been reported about the performance of LIBS in reduced pressure environments as well as in various gases other than air. PMID:22399914

Laser Induced Breakdown Spectroscopy Based on Single Beam Splitting and Geometric Configuration for Effective Signal Enhancement

PubMed Central

Yang, Guang; Lin, Qingyu; Ding, Yu; Tian, Di; Duan, Yixiang

2015-01-01

A new laser induced breakdown spectroscopy (LIBS) based on single-beam-splitting (SBS) and proper optical geometric configuration has been initially explored in this work for effective signal enhancement. In order to improve the interaction efficiency of laser energy with the ablated material, a laser beam operated in pulse mode was divided into two streams to ablate/excite the target sample in different directions instead of the conventional one beam excitation in single pulse LIBS (SP-LIBS). In spatial configuration, the laser beam geometry plays an important role in the emission signal enhancement. Thus, an adjustable geometric configuration with variable incident angle between the two splitted laser beams was constructed for achieving maximum signal enhancement. With the optimized angles of 60° and 70° for Al and Cu atomic emission lines at 396.15 nm and 324.75 nm respectively, about 5.6- and 4.8-folds signal enhancements were achieved for aluminum alloy and copper alloy samples compared to SP-LIBS. Furthermore, the temporal analysis, in which the intensity of atomic lines in SP-LIBS decayed at least ten times faster than the SBS-LIBS, proved that the energy coupling efficiency of SBS-LIBS was significantly higher than that of SP-LIBS. PMID:25557721

Genetic Heterogeneity in Mycobacterium tuberculosis Isolates Reflected in IS6110 Restriction Fragment Length Polymorphism Patterns as Low-Intensity Bands

PubMed Central

de Boer, Annette S.; Kremer, Kristin; Borgdorff, Martien W.; de Haas, Petra E. W.; Heersma, Herre F.; van Soolingen, Dick

2000-01-01

Mycobacterium tuberculosis isolates with identical IS6110 restriction fragment length polymorphism (RFLP) patterns are considered to originate from the same ancestral strain and thus to reflect ongoing transmission. In this study, we investigated 1,277 IS6110 RFLP patterns for the presence of multiple low-intensity bands (LIBs), which may indicate infections with multiple M. tuberculosis strains. We did not find any multiple LIBs, suggesting that multiple infections are rare in the Netherlands. However, we did observe a few LIBs in 94 patterns (7.4%) and examined the nature of this phenomenon. With single-colony cultures it was found that LIBs mostly represent mixed bacterial populations with slightly different RFLP patterns. Mixtures were expressed in RFLP patterns as LIBs when 10 to 30% of the DNA analyzed originated from a bacterial population with another RFLP pattern. Presumably, a part of the LIBs did not represent mixed bacterial populations, as in some clusters all strains exhibited LIBs in their RFLP patterns. The occurrence of LIBs was associated with increased age in patients. This may reflect either a gradual change of the bacterial population in the human body over time or IS6110-mediated genetic adaptation of M. tuberculosis to changes in the environmental conditions during the dormant state or reactivation thereafter. PMID:11101583

A Simple Prelithiation Strategy To Build a High-Rate and Long-Life Lithium-Ion Battery with Improved Low-Temperature Performance.

PubMed

Liu, Yao; Yang, Bingchang; Dong, Xiaoli; Wang, Yonggang; Xia, Yongyao

2017-12-22

Lithium-ion batteries (LIBs) are being used to power the commercial electric vehicles (EVs). However, the charge/discharge rate and life of current LIBs still cannot satisfy the further development of EVs. Furthermore, the poor low-temperature performance of LIBs limits their application in cold climates and high altitude areas. Herein, a simple prelithiation method is developed to fabricate a new LIB. In this strategy, a Li 3 V 2 (PO 4 ) 3 cathode and a pristine hard carbon anode are used to form a primary cell, and the initial Li + extraction from Li 3 V 2 (PO 4 ) 3 is used to prelithiate the hard carbon. Then, the self-formed Li 2 V 2 (PO 4 ) 3 cathode and prelithiated hard carbon anode are used to form a 4 V LIB. The LIB exhibits a maximum energy density of 208.3 Wh kg -1 , a maximum power density of 8291 W kg -1 and a long life of 2000 cycles. When operated at -40 °C, the LIB can keep 67 % capacity of room temperature, which is much better than conventional LIBs. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Genome-wide screen of Saccharomyces cerevisiae for killer toxin HM-1 resistance.

PubMed

Miyamoto, Masahiko; Furuichi, Yasuhiro; Komiyama, Tadazumi

2011-01-01

We screened a set of Saccharomyces cerevisiae deletion mutants for resistance to killer toxin HM-1, which kills susceptible yeasts through inhibiting 1,3-beta-glucan synthase. By using HM-1 plate assay, we found that eight gene-deletion mutants had higher HM-1-resistance compared with the wild-type. Among these eight genes, five--ALG3, CAX4, MNS1, OST6 and YBL083C--were associated with N-glycan formation and maturation. The ALG3 gene has been shown before to be highly resistant to HM-1. The YBL083C gene may be a dubious open reading frame that overlaps partially the ALG3 gene. The deletion mutant of the MNS1 gene that encodes 1,2-alpha-mannosidase showed with a 13-fold higher HM-1 resistance compared with the wild-type. By HM-1 binding assay, the yeast plasma membrane fraction of alg3 and mns1 cells had less binding ability compared with wild-type cells. These results indicate that the presence of the terminal 1,3-alpha-linked mannose residue of the B-chain of the N-glycan structure is essential for interaction with HM-1. A deletion mutant of aquaglyceroporin Fps1p also showed increased HM-1 resistance. A deletion mutant of osmoregulatory mitogen-activated protein kinase Hog1p was more sensitive to HM-1, suggesting that high-osmolarity glycerol pathways plays an important role in the compensatory response to HM-1 action. Copyright © 2010 John Wiley & Sons, Ltd.

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

Chung, Donald; Elgqvist, Emma; Santhanagopalan, Shriram

Manufacturing capacity for lithium-ion batteries (LIBs) — which power many consumer electronics and are increasingly used to power electric vehicles — is heavily concentrated in East Asia. To illuminate the factors that drive regional competitiveness in automotive LIB cell production, this study models cell manufacturing cost and minimum sustainable price, and examines development of LIB supply chains and current LIB market conditions. The study shows that factors driving the cost competitiveness of LIB manufacturing locations are mostly built—supply chain developments and competition, access to materials, and production expertise. Some regional costs — including cost of capital, labor, and materials —more » are significant and should be considered.« less

Low values of 5-hydroxymethylcytosine (5hmC), the "sixth base," are associated with anaplasia in human brain tumors.

PubMed

Kraus, Theo F J; Globisch, Daniel; Wagner, Mirko; Eigenbrod, Sabina; Widmann, David; Münzel, Martin; Müller, Markus; Pfaffeneder, Toni; Hackner, Benjamin; Feiden, Wolfgang; Schüller, Ulrich; Carell, Thomas; Kretzschmar, Hans A

2012-10-01

5-Methylcytosine (5 mC) in genomic DNA has important epigenetic functions in embryonic development and tumor biology. 5-Hydroxymethylcytosine (5 hmC) is generated from 5 mC by the action of the TET (Ten-Eleven-Translocation) enzymes and may be an intermediate to further oxidation and finally demethylation of 5 mC. We have used immunohistochemistry (IHC) and isotope-based liquid chromatography mass spectrometry (LC-MS) to investigate the presence and distribution of 5 hmC in human brain and brain tumors. In the normal adult brain, IHC identified 61.5% 5 hmC positive cells in the cortex and 32.4% 5 hmC in white matter (WM) areas. In tumors, positive staining of cells ranged from 1.1% in glioblastomas (GBMs) (WHO Grade IV) to 8.9% in Grade I gliomas (pilocytic astrocytomas). In the normal adult human brain, LC-MS also showed highest values in cortical areas (1.17% 5 hmC/dG [deoxyguanosine]), in the cerebral WM we measured around 0.70% 5 hmC/dG. levels were related to tumor differentiation, ranging from lowest values of 0.078% 5 hmC/dG in GBMs (WHO Grade IV) to 0.24% 5 hmC/dG in WHO Grade II diffuse astrocytomas. 5 hmC measurements were unrelated to 5 mC values. We find that the number of 5 hmC positive cells and the amount of 5 hmC/dG in the genome that has been proposed to be related to pluripotency and lineage commitment in embryonic stem cells is also associated with brain tumor differentiation and anaplasia. Copyright © 2012 UICC.

Application of Laser Induced Breakdown Spectroscopy to Monitor Rare Earth Ions in Glass Matrix

NASA Astrophysics Data System (ADS)

Sharma, Prakash; Carter, Michael; Kumar, Akshaya

2013-05-01

The Laser Induced breakdown spectroscopy (LIBS) is a real time online technique that can be used to monitor the concentration of rare earth ions in amorphous glass matrix. This study has significant application in the glass industry where the composition of the glass can be monitored in real time using LIBS technology for quality control. The Eu3 + ions doped silicate glasses were developed via sol gel method. The glasses of varying molar percentages of Eu3 + (0.02, 0.05 and 0.08 mole percent), were prepared to study the effect of variation in concentration of Eu3 + ions on the LIBS signal and to calculate its limit of detection (LOD). The spectral assignment of the observed LIBS spectrum has been made. In order to find the maximum signal to noise ratio, we also recorded the intensity of LIBS signal for various integration start delay (ISD) time at a constant power of (pulsed Nd: YAG) laser. The ocean optics LIBS 2500plus spectrometer along with a Q switched Nd:YAG laser (Quantel, Big Sky) were used to record the LIBS spectrum.

5-Hydroxymethylcytosine is a predominantly stable DNA modification

NASA Astrophysics Data System (ADS)

Bachman, Martin; Uribe-Lewis, Santiago; Yang, Xiaoping; Williams, Michael; Murrell, Adele; Balasubramanian, Shankar

2014-12-01

5-Hydroxymethylcytosine (hmC) is an oxidation product of 5-methylcytosine which is present in the deoxyribonucleic acid (DNA) of most mammalian cells. Reduction of hmC levels in DNA is a hallmark of cancers. Elucidating the dynamics of this oxidation reaction and the lifetime of hmC in DNA is fundamental to understanding hmC function. Using stable isotope labelling of cytosine derivatives in the DNA of mammalian cells and ultrasensitive tandem liquid-chromatography mass spectrometry, we show that the majority of hmC is a stable modification, as opposed to a transient intermediate. In contrast with DNA methylation, which occurs immediately during replication, hmC forms slowly during the first 30 hours following DNA synthesis. Isotopic labelling of DNA in mouse tissues confirmed the stability of hmC in vivo and demonstrated a relationship between global levels of hmC and cell proliferation. These insights have important implications for understanding the states of chemically modified DNA bases in health and disease.

The anti-CMS technique for genome-wide mapping of 5-hydroxymethylcytosine.

PubMed

Huang, Yun; Pastor, William A; Zepeda-Martínez, Jorge A; Rao, Anjana

2012-10-01

5-Hydroxymethylcytosine (5hmC) is a recently discovered base in the mammalian genome, produced upon oxidation of 5-methylcytosine (5mC) in a process catalyzed by TET proteins. The biological functions of 5hmC and further oxidation products of 5mC are under intense investigation, as they are likely intermediates in DNA demethylation pathways. Here we describe a novel protocol to profile 5hmC at a genome-wide scale. This approach is based on sodium bisulfite-mediated conversion of 5hmC to cytosine-5-methylenesulfonate (CMS); CMS-containing DNA fragments are then immunoprecipitated using a CMS-specific antiserum. The anti-CMS technique is highly specific with a low background, and is much less dependent on 5hmC density than anti-5hmC immunoprecipitation (IP). Moreover, it does not enrich for CA and CT repeats, as noted for 5hmC DNA IP using antibodies to 5hmC. The anti-CMS protocol takes 3 d to complete.

[Effects of conjunctive application of Chinese herbal medicine residue compost and chemical fertilizer on ferulic acid and ligustilide contents in Angelica sinensis].

PubMed

Fan, Qin; Wang, Yin-Quan; An, Pei-Kun; Guo, Zeng-Xiang; Xia, Qi

2013-02-01

To investigate the effects of conjunctive application of Chinese herbal medicine residue compost (CHMRC) and chemical fertilizer on ferulic acid and ligustilide contents in Angelica sinensis. There were six treatments, viz. T1: control (no fertilizer), T2: chemical fertilizer (the fertilizer rates for N, P2O5 and K2O were 90, 90 and 60 kg/hm2, respectively), T3:1 350 kg/hm2 CHMRC, 86 kg/hm2N, 84 kg/hm2 P2O5 and 52 kg/hm2 K2O, T4:2 250 kg/hm2 CHMRC, 83 kg/hm2N, 81 kg/hm2 P2O5 and 47 kg/hm2 K2O, T5: 3 150 kg/hm2 CHMRC, 82 kg/hm2N, 77 kg/hm2 P2O5 and 42 kg/hm2 K2O, and T6: CHMRC at 4 500 kg/hm2 (nitrogen application rate was the same as T2). Along with growth stages, the changing trend of ferulic acid and ligustilide contents from all treatments showed a "J"-shaped curve; Ferulic acid and ligustilide contents in the roots at the harvest were increased compared with the beginning by over 16.0% and 117.0%, respectively, in which the maximum increasing rates of ferulic acid and ligustilide contents occurred in the chemical fertilizer treatment (T2), and reached at 68.4% and 176.6%, respectively; Compared with control, T2, T5 and T6 significantly increased ferulic acid content by 19.2% - 25.6%, and ligustilide content by 9.1% - 11.2% (P < 0.05). The results are obtained as following: the application of CHMRC and/or chemical fertilizer does not change the chemical composition in the root of Angelica sinensis, but has some effects on the content of related ingredients. This research indicates that T5 should be recommended for Angelica sinensis growing, which will ensure a production of high quality, low cost and environment-friendly.

Perceptions of the Muslim religious leaders and their attitudes on herbal medicine in Bangladesh: a cross-sectional study

PubMed Central

2011-01-01

Background Herbal Medicines (HMs) are playing major roles in the health of the millions of people worldwide. Muslim Religious Leader (MRLs), being an important component of the society with huge influence on it, could contribute a lot to promote HM. This study was aimed at evaluating perceptions of the MRLs, their satisfaction and attitudes towards HM in Bangladesh. Methods This cross-sectional study collected data from a purposive sample of 503 MRLs using an interviewer-administered structured questionnaire during December 2010 and January 2011. Main outcome measures included sociodemographic variables, MRLs' preferences in using HMs, their satisfaction and intent to use HMs in the future, and finally MRLs' attitudes toward HM use. Results Although two-fifth (40.4%) of the MRLs preferred HM among different form of complementary and alternative medicines, they used orthodox medicine (OM) more frequently than HM in last one year. Majority believed that HM was effective for all age groups (52.6%) and both sexes (74.5%). One-third felt that HM was more effective for chronic diseases, 68.5% felt that it only promotes health, and 40.8% said it keeps them relaxed. About 98.0% of the respondents experienced 'no harm' but 'benefit' from HM; naturally, they were satisfied with HM and were willing to recommend it to others. Urban, older (>40 years), and 'single' respondents were more likely to use HM (gender and education adjusted odds ratios = 1.7 [95% confidence interval, CI = 1.1-2.6], 1.9 [95% CI = 1.3-3.0], and 1.6 [95% CI = 1.2-2.1], respectively). Overall, respondents exhibited very positive attitude towards HM with mean score of 4.2 (range, 3.7-4.6) of a 5-point Likert scale (Score 5 for strongly agree to 1 for strongly disagree). Conclusions We report adequate perceptions, satisfaction, and very positive attitudes towards HM among MRLs. Mass media had a significant contribution towards its promotion. If HM are to assume a respected place in the contemporary healthcare, its acceptance among general population needs to be established through incorporating MRLs in the process of HM promotion in Bangladesh. PMID:21943359

Study on the effect of beam propagation through atmospheric turbulence on standoff nanosecond laser induced breakdown spectroscopy measurements.

PubMed

Laserna, J J; Reyes, R Fernández; González, R; Tobaria, L; Lucena, P

2009-06-08

We report on an experimental study of the effect of atmospheric turbulence on laser induced breakdown spectroscopy (LIBS) measurements. The characteristics of the atmosphere dictate specific performance constraints to this technology. Unlike classical laboratory LIBS systems where the distance to the sample is well known and characterized, LIBS systems working at several tens of meters to the target have specific atmospheric propagation conditions that cause the quality of the LIBS signals to be affected to a significant extent. Using a new LIBS based sensor system fitted with a nanosecond laser emitting at 1064 nm, propagation effects at distances of up to 120 m were investigated. The effects observed include wander and scintillation in the outgoing laser beam and in the return atomic emission signal. Plasmas were formed on aluminium targets. Average signal levels and signal fluctuations are measured so the effect of atmospheric turbulence on LIBS measurements is quantified.

Generation and management of waste electric vehicle batteries in China.

PubMed

Xu, ChengJian; Zhang, Wenxuan; He, Wenzhi; Li, Guangming; Huang, Juwen; Zhu, Haochen

2017-09-01

With the increasing adoption of EVs (electric vehicles), a large number of waste EV LIBs (electric vehicle lithium-ion batteries) were generated in China. Statistics showed generation of waste EV LIBs in 2016 reached approximately 10,000 tons, and the amount of them would be growing rapidly in the future. In view of the deleterious effects of waste EV LIBs on the environment and the valuable energy storage capacity or materials that can be reused in them, China has started emphasizing the management, reuse, and recycling of them. This paper presented the generation trend of waste EV LIBs and focused on interrelated management development and experience in China. Based on the situation of waste EV LIBs management in China, existing problems were analyzed and summarized. Some recommendations were made for decision-making organs to use as valuable references to improve the management of waste EV LIBs and promote the sustainable development of EVs.

Materials insights into low-temperature performances of lithium-ion batteries

NASA Astrophysics Data System (ADS)

Zhu, Gaolong; Wen, Kechun; Lv, Weiqiang; Zhou, Xingzhi; Liang, Yachun; Yang, Fei; Chen, Zhilin; Zou, Minda; Li, Jinchao; Zhang, Yuqian; He, Weidong

2015-12-01

Lithium-ion batteries (LIBs) have been employed in many fields including cell phones, laptop computers, electric vehicles (EVs) and stationary energy storage wells due to their high energy density and pronounced recharge ability. However, energy and power capabilities of LIBs decrease sharply at low operation temperatures. In particular, the charge process becomes extremely sluggish at temperatures below -20 °C, which severely limits the applications of LIBs in some cold areas during winter. Extensive research has shown that the electrolyte/electrode composition and microstructure are of fundamental importance to low-temperature performances of LIBs. In this report, we review the recent findings in the role of electrolytes, anodes, and cathodes in the low temperature performances of LIBs. Our overview aims to understand comprehensively the fundamental origin of low-temperature performances of LIBs from a materials perspective and facilitates the development of high-performance lithium-ion battery materials that are operational at a large range of working temperatures.

Elemental profiling of laser cladded multilayer coatings by laser induced breakdown spectroscopy and energy dispersive X-ray spectroscopy

NASA Astrophysics Data System (ADS)

Lednev, V. N.; Sdvizhenskii, P. A.; Filippov, M. N.; Grishin, M. Ya.; Filichkina, V. A.; Stavertiy, A. Ya.; Tretyakov, R. S.; Bunkin, A. F.; Pershin, S. M.

2017-09-01

Multilayer tungsten carbide wear resistant coatings were analyzed by laser induced breakdown spectroscopy (LIBS) and energy dispersive X-ray (EDX) spectroscopy. Coaxial laser cladding technique was utilized to produce tungsten carbide coating deposited on low alloy steel substrate with additional inconel 625 interlayer. EDX and LIBS techniques were used for elemental profiling of major components (Ni, W, C, Fe, etc.) in the coating. A good correlation between EDX and LIBS data was observed while LIBS provided additional information on light element distribution (carbon). A non-uniform distribution of tungsten carbide grains along coating depth was detected by both LIBS and EDX. In contrast, horizontal elemental profiling showed a uniform tungsten carbide particles distribution. Depth elemental profiling by layer-by-layer LIBS analysis was demonstrated to be an effective method for studying tungsten carbide grains distribution in wear resistant coating without any sample preparation.

Long-wave, infrared laser-induced breakdown (LIBS) spectroscopy emissions from energetic materials.

PubMed

Yang, Clayton S-C; Brown, Ei E; Hommerich, Uwe; Jin, Feng; Trivedi, Sudhir B; Samuels, Alan C; Snyder, A Peter

2012-12-01

Laser-induced breakdown spectroscopy (LIBS) has shown great promise for applications in chemical, biological, and explosives sensing and has significant potential for real-time standoff detection and analysis. In this study, LIBS emissions were obtained in the mid-infrared (MIR) and long-wave infrared (LWIR) spectral regions for potential applications in explosive material sensing. The IR spectroscopy region revealed vibrational and rotational signatures of functional groups in molecules and fragments thereof. The silicon-based detector for conventional ultraviolet-visible LIBS operations was replaced with a mercury-cadmium-telluride detector for MIR-LWIR spectral detection. The IR spectral signature region between 4 and 12 μm was mined for the appearance of MIR and LWIR-LIBS emissions directly indicative of oxygenated breakdown products as well as dissociated, and/or recombined sample molecular fragments. Distinct LWIR-LIBS emission signatures from dissociated-recombination sample molecular fragments between 4 and 12 μm are observed for the first time.

Laser-induced breakdown spectroscopy (LIBS): an overview of recent progress and future potential for biomedical applications.

PubMed

Rehse, S J; Salimnia, H; Miziolek, A W

2012-02-01

The recent progress made in developing laser-induced breakdown spectroscopy (LIBS) has transformed LIBS from an elemental analysis technique to one that can be applied for the reagentless analysis of molecularly complex biological materials or clinical specimens. Rapid advances in the LIBS technology have spawned a growing number of recently published articles in peer-reviewed journals which have consistently demonstrated the capability of LIBS to rapidly detect, biochemically characterize and analyse, and/or accurately identify various biological, biomedical or clinical samples. These analyses are inherently real-time, require no sample preparation, and offer high sensitivity and specificity. This overview of the biomedical applications of LIBS is meant to summarize the research that has been performed to date, as well as to suggest to health care providers several possible specific future applications which, if successfully implemented, would be significantly beneficial to humankind.

Large spin-orbit torques in Pt/Co-Ni/W heterostructures

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

Yu, Jiawei; Qiu, Xuepeng; Legrand, William

2016-07-25

The spin orbit torques (SOTs) in perpendicularly magnetized Co-Ni multilayers sandwiched between two heavy metals (HM) have been studied. By exploring various HM materials, we show an efficient enhancement or cancellation of the total SOT, depending on the combination of the two HM materials. The maximum SOT effective field is obtained in Pt/Co-Ni/W heterostructures. We also model our double HM system and show that the effective spin Hall angle has a peak value at certain HM thicknesses. Measuring the SOT in Pt/Co-Ni/W for various W thicknesses confirms an effective spin Hall angle up to 0.45 in our double HM system.

A feasibility test to estimate the duration of phytoextraction of heavy metals from polluted soils.

PubMed

Japenga, J; Koopmans, G F; Song, J; Römkens, P F A M

2007-01-01

The practical applicability of heavy metal (HM) phytoextraction depends heavily on its duration. Phytoextraction duration is the main cost factorfor phytoextraction, both referring to recurring economic costs during phytoextraction and to the cost of the soil having no economic value during phytoextraction. An experiment is described here, which is meant as a preliminary feasibility test before starting a phytoextraction scheme in practice, to obtain a more realistic estimate of the phytoextraction duration of a specific HM-polluted soil. In the experiment, HM-polluted soil is mixed at different ratios with unpolluted soil of comparable composition to mimic the gradual decrease of the HM content in the target HM-polluted soil during phytoextraction. After equilibrating the soil mixtures, one cropping cycle is carried out with the plant species of interest. At harvest, the adsorbed HM contents in the soil and the HM contents in the plant shoots are determined. The adsorbed HM contents in the soil are then related to the HM contents in the plant shoots by a log-log linear relationship that can then be used to estimate the phytoextraction duration of a specific HM-polluted soil. This article describes and evaluates the merits of such a feasibility experiment. Potential drawbacks regarding the accuracy of the described approach are discussed and a greenhouse-field extrapolation procedure is proposed.

Double pulse laser induced breakdown spectroscopy: A potential tool for the analysis of contaminants and macro/micronutrients in organic mineral fertilizers.

PubMed

Nicolodelli, Gustavo; Senesi, Giorgio Saverio; de Oliveira Perazzoli, Ivan Luiz; Marangoni, Bruno Spolon; De Melo Benites, Vinícius; Milori, Débora Marcondes Bastos Pereira

2016-09-15

Organic fertilizers are obtained from waste of plant or animal origin. One of the advantages of organic fertilizers is that, from the composting, it recycles waste-organic of urban and agriculture origin, whose disposal would cause environmental impacts. Fast and accurate analysis of both major and minor/trace elements contained in organic mineral and inorganic fertilizers of new generation have promoted the application of modern analytical techniques. In particular, laser induced breakdown spectroscopy (LIBS) is showing to be a very promising, quick and practical technique to detect and measure contaminants and nutrients in fertilizers. Although, this technique presents some limitations, such as a low sensitivity, if compared to other spectroscopic techniques, the use of double pulse (DP) LIBS is an alternative to the conventional LIBS in single pulse (SP). The macronutrients (Ca, Mg, K, P), micronutrients (Cu, Fe, Na, Mn, Zn) and contaminant (Cr) in fertilizer using LIBS in SP and DP configurations were evaluated. A comparative study for both configurations was performed using optimized key parameters for improving LIBS performance. The limit of detection (LOD) values obtained by DP LIBS increased up to seven times as compared to SP LIBS. In general, the marked improvement obtained when using DP system in the simultaneous LIBS quantitative determination for fertilizers analysis could be ascribed to the larger ablated mass of the sample. The results presented in this study show the promising potential of the DP LIBS technique for a qualitative analysis in fertilizers, without requiring sample preparation with chemical reagents. Copyright © 2016 Elsevier B.V. All rights reserved.

Genome-wide mapping of 5-hydroxymethylcytosine in embryonic stem cells.

PubMed

Pastor, William A; Pape, Utz J; Huang, Yun; Henderson, Hope R; Lister, Ryan; Ko, Myunggon; McLoughlin, Erin M; Brudno, Yevgeny; Mahapatra, Sahasransu; Kapranov, Philipp; Tahiliani, Mamta; Daley, George Q; Liu, X Shirley; Ecker, Joseph R; Milos, Patrice M; Agarwal, Suneet; Rao, Anjana

2011-05-19

5-hydroxymethylcytosine (5hmC) is a modified base present at low levels in diverse cell types in mammals. 5hmC is generated by the TET family of Fe(II) and 2-oxoglutarate-dependent enzymes through oxidation of 5-methylcytosine (5mC). 5hmC and TET proteins have been implicated in stem cell biology and cancer, but information on the genome-wide distribution of 5hmC is limited. Here we describe two novel and specific approaches to profile the genomic localization of 5hmC. The first approach, termed GLIB (glucosylation, periodate oxidation, biotinylation) uses a combination of enzymatic and chemical steps to isolate DNA fragments containing as few as a single 5hmC. The second approach involves conversion of 5hmC to cytosine 5-methylenesulphonate (CMS) by treatment of genomic DNA with sodium bisulphite, followed by immunoprecipitation of CMS-containing DNA with a specific antiserum to CMS. High-throughput sequencing of 5hmC-containing DNA from mouse embryonic stem (ES) cells showed strong enrichment within exons and near transcriptional start sites. 5hmC was especially enriched at the start sites of genes whose promoters bear dual histone 3 lysine 27 trimethylation (H3K27me3) and histone 3 lysine 4 trimethylation (H3K4me3) marks. Our results indicate that 5hmC has a probable role in transcriptional regulation, and suggest a model in which 5hmC contributes to the 'poised' chromatin signature found at developmentally-regulated genes in ES cells.

Breast milk nutrient content and infancy growth.

PubMed

Prentice, Philippa; Ong, Ken K; Schoemaker, Marieke H; van Tol, Eric A F; Vervoort, Jacques; Hughes, Ieuan A; Acerini, Carlo L; Dunger, David B

2016-06-01

Benefits of human breast milk (HM) in avoiding rapid infancy weight gain and later obesity could relate to its nutrient content. We tested the hypothesis that differential HM total calorie content (TCC) or macronutrient contents may be associated with infancy growth. HM hindmilk samples were collected at ages 4-8 weeks from 614 mothers participating in a representative birth cohort, with repeated infancy anthropometry. HM triglyceride (fat), lipid analytes and lactose (carbohydrate) were measured by (1) H-NMR, and protein content by the Dumas method. TCC and %macronutrients were determined. In 614 HM samples, fat content was as follows: [median(IQR)]: 2.6 (1.7-3.6) g/100 mL, carbohydrate: 8.6 (8.2-8.8) g/100 mL, protein: 1.2 (1.1-1.2) g/100 mL; TCC: 61.8 (53.7-71.3) kcal/100 mL. HM of mothers exclusively breast feeding vs. mixed feeding was more calorific with higher %fat, lower %carbohydrate and lower %protein. Higher HM TCC was associated with lower 12-months body mass index (BMI)/adiposity, and lower 3-12 months gains in weight/BMI. HM %fat was inversely related to 3-12 months gains in weight, BMI and adiposity, whereas %carbohydrate was positively related to these measures. HM %protein was positively related to 12-months BMI. HM analysis showed wide variation in %macronutrients. Although data on milk intakes were unavailable, our findings suggest functional relevance of HM milk composition to infant growth. ©2016 The Authors. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.

New applications of laser-induced breakdown and stand-off Raman spectroscopy

NASA Astrophysics Data System (ADS)

Snyder, Marion Lawrence

Two novel spectroscopic applications, with the common theme of remote spectroscopy are described. In one application, laser-induced breakdown spectroscopy (LIBS) is investigated for deep ocean measurements of hydrothermal vent chemistry. This technique is demonstrated for the first time for solution measurements at pressures corresponding to those found at hydrothermal vent sites, at ocean depths of one to three kilometers. In the other application, Raman spectroscopy is investigated for stand-off detection of high explosive (HE) materials. We demonstrate several HE materials in silica can be measured at 50-meter range under ambient light conditions, a new record for this application. Chapters one through three of this dissertation contain published and recently submitted articles describing LIBS for in situ multi-elemental detection in high-pressure aqueous environments such as the deep ocean. Initial work shows the potential of single-pulse LIBS (SP-LIBS) to measure dissolved elements (e.g., Na, Ca, Li, K, and Mn) at the part-per-million level in aqueous solutions at pressures exceeding 276 bar. Dual-pulse LIBS (DP-LIBS) of high-pressure aqueous solutions is also presented. We show significant DP-LIBS enhancements are achieved through excitation of a vapor bubble formed by laser-induced breakdown of the solution with a previous laser pulse, thereby increasing the sensitivity of LIBS and allowing additional elements to be measured. Preliminary findings show that increasing solution pressure has a detrimental effect on DP-LIBS emission intensities, such that little if any DP-LIBS emission was observed above approximately 100 bar. Recent results suggest a direct relationship exists between the size of the bubble and the resulting DP-LIBS emission, and that reduction in bubble size and lifetime at elevated pressure lead to the decreased DP-LIBS emission. Chapter four contains published work examining the potential of stand-off Raman spectroscopy for remote HE detection. A small, transportable, telescope-based standoff Raman system is demonstrated for detection of HE materials, including RDX, TNT, and PETN, and simulants at distances up to 50 meters in ambient light conditions. Possible detection limits on the hundreds of parts-per-million level and detection ranges of hundreds of meters are suggested. Merits of pulsed laser excitation sources and intensified charge-coupled devices (ICCD) for detection are discussed.

Laser-induced breakdown spectroscopy (LIBS): applications in environmental issues

NASA Astrophysics Data System (ADS)

Couris, Stelios; Hatziapostolou, A.; Anglos, Dmitrios; Mavromanolakis, A.; Fotakis, Costas

1996-11-01

Results are presented from three different applications of laser induced breakdown spectroscopy (LIBS) in problems of environmental interest. In one case, LIBS is applied in the on-line control of the nickel recovery process, by monitoring the nickel content of molten ferronickel slabs, in a laboratory scale experiment. In a second case, LIBS is used in the identification of polymer materials, and on the basis of spectral features, criteria are proposed for the distinction among different types of plastic materials. Also, in preliminary experiments, the use of LIBS with respect to the detection of heavy and toxic metals in paints and the possibility of performing depth profile analysis of multiple paint layers is examined.

Laser-induced breakdown spectroscopy using mid-infrared femtosecond pulses

DOE PAGES

Hartig, K. C.; Colgan, J.; Kilcrease, D. P.; ...

2015-07-30

Here, we report on a laser-induced breakdown spectroscopy (LIBS) experiment driven by mid-infrared (2.05-μm) fs pulses, in which time-resolved emission spectra of copper were studied. Ab-initio modeling is consistent with the results of new fs measurements at 2.05 μm and traditional 800-nm fs-LIBS. Ablation by mid-infrared fs pulses results in a plasma with a lower plasma density and temperature compared to fs-LIBS performed at shorter laser wavelength. LIBS driven by mid-infrared fs pulses results in a signal-to-background ratio ~50% greater and a signal-to-noise ratio ~40% lower than fs-LIBS at near-infrared laser wavelength.

Comparative measurements of mineral elements in milk powders with laser-induced breakdown spectroscopy and inductively coupled plasma atomic emission spectroscopy.

PubMed

Lei, W Q; El Haddad, J; Motto-Ros, V; Gilon-Delepine, N; Stankova, A; Ma, Q L; Bai, X S; Zheng, L J; Zeng, H P; Yu, J

2011-07-01

Mineral elements contained in commercially available milk powders, including seven infant formulae and one adult milk, were analyzed with inductively coupled plasma atomic emission spectrometry (ICP-AES) and laser-induced breakdown spectroscopy (LIBS). The purpose of this work was, through a direct comparison of the analytical results, to provide an assessment of the performance of LIBS, and especially of the procedure of calibration-free LIBS (CF-LIBS), to deal with organic compounds such as milk powders. In our experiments, the matrix effect was clearly observed affecting the analytical results each time laser ablation was employed for sampling. Such effect was in addition directly observed by determining the physical parameters of the plasmas induced on the different samples. The CF-LIBS procedure was implemented to deduce the concentrations of Mg and K with Ca as the internal reference element. Quantitative analytical results with CF-LIBS were validated with ICP-AES measurements and nominal concentrations specified for commercial milks. The obtained good results with the CF-LIBS procedure demonstrate its capacity to take into account the difference in physical parameters of the plasma in the calculation of the concentrations of mineral elements, which allows a significant reduction of the matrix effect related to laser ablation. We finally discuss the way to optimize the implementation of the CF-LIBS procedure for the analysis of mineral elements in organic materials.

Addressing the Interface Issues in All-Solid-State Bulk-Type Lithium Ion Battery via an All-Composite Approach.

PubMed

Chen, Ru-Jun; Zhang, Yi-Bo; Liu, Ting; Xu, Bing-Qing; Lin, Yuan-Hua; Nan, Ce-Wen; Shen, Yang

2017-03-22

All-solid-state bulk-type lithium ion batteries (LIBs) are considered ultimate solutions to the safety issues associated with conventional LIBs using flammable liquid electrolyte. The development of bulk-type all-solid-state LIBs has been hindered by the low loading of active cathode materials, hence low specific surface capacity, and by the high interface resistance, which results in low rate and cyclic performance. In this contribution, we propose and demonstrate a synergistic all-composite approach to fabricating flexible all-solid-state LIBs. PEO-based composite cathode layers (filled with LiFePO 4 particles) of ∼300 μm in thickness and composite electrolyte layers (filled with Al-LLZTO particles) are stacked layer-by-layer with lithium foils as negative layer and hot-pressed into a monolithic all-solid-state LIB. The flexible LIB delivers a high specific discharge capacity of 155 mAh/g, which corresponds to an ultrahigh surface capacity of 10.8 mAh/cm 2 , exhibits excellent capacity retention up to at least 10 cycles and could work properly under harsh operating conditions such as bending or being sectioned into pieces. The all-composite approach is favorable for improving both mesoscopic and microscopic interfaces inside the all-solid-state LIB and may provide a new toolbox for design and fabrication of all-solid-state LIBs.

Laser induced breakdown spectroscopy (LIBS) as a rapid tool for material analysis

NASA Astrophysics Data System (ADS)

Hussain, T.; Gondal, M. A.

2013-06-01

Laser induced breakdown spectroscopy (LIBS) is a novel technique for elemental analysis based on laser-generated plasma. In this technique, laser pulses are applied for ablation of the sample, resulting in the vaporization and ionization of sample in hot plasma which is finally analyzed by the spectrometer. The elements are identified by their unique spectral signatures. LIBS system was developed for elemental analysis of solid and liquid samples. The developed system was applied for qualitative as well as quantitative measurement of elemental concentration present in iron slag and open pit ore samples. The plasma was generated by focusing a pulsed Nd:YAG laser at 1064 nm on test samples to study the capabilities of LIBS as a rapid tool for material analysis. The concentrations of various elements of environmental significance such as cadmium, calcium, magnesium, chromium, manganese, titanium, barium, phosphorus, copper, iron, zinc etc., in these samples were determined. Optimal experimental conditions were evaluated for improving the sensitivity of developed LIBS system through parametric dependence study. The laser-induced breakdown spectroscopy (LIBS) results were compared with the results obtained using standard analytical technique such as inductively couple plasma emission spectroscopy (ICP). Limit of detection (LOD) of our LIBS system were also estimated for the above mentioned elements. This study demonstrates that LIBS could be highly appropriate for rapid online analysis of iron slag and open pit waste.

Laser-induced breakdown spectroscopy application in environmental monitoring of water quality: a review.

PubMed

Yu, Xiaodong; Li, Yang; Gu, Xiaofeng; Bao, Jiming; Yang, Huizhong; Sun, Li

2014-12-01

Water quality monitoring is a critical part of environmental management and protection, and to be able to qualitatively and quantitatively determine contamination and impurity levels in water is especially important. Compared to the currently available water quality monitoring methods and techniques, laser-induced breakdown spectroscopy (LIBS) has several advantages, including no need for sample pre-preparation, fast and easy operation, and chemical free during the process. Therefore, it is of great importance to understand the fundamentals of aqueous LIBS analysis and effectively apply this technique to environmental monitoring. This article reviews the research conducted on LIBS analysis for liquid samples, and the article content includes LIBS theory, history and applications, quantitative analysis of metallic species in liquids, LIBS signal enhancement methods and data processing, characteristics of plasma generated by laser in water, and the factors affecting accuracy of analysis results. Although there have been many research works focusing on aqueous LIBS analysis, detection limit and stability of this technique still need to be improved to satisfy the requirements of environmental monitoring standard. In addition, determination of nonmetallic species in liquid by LIBS is equally important and needs immediate attention from the community. This comprehensive review will assist the readers to better understand the aqueous LIBS technique and help to identify current research needs for environmental monitoring of water quality.

Generation of a Database of Laboratory Laser-Induced Breakdown Spectroscopy (LIBS) Spectra and Associated Analysis Software

NASA Astrophysics Data System (ADS)

Anderson, R. B.; Clegg, S. M.; Graff, T.; Morris, R. V.; Laura, J.

2015-06-01

We describe plans to generate a database of LIBS spectra of planetary analog materials and develop free, open-source software to enable the planetary community to analyze LIBS (and other spectral) data.

Evidence-based methods that promote human milk feeding of preterm infants: an expert review

PubMed Central

Meier, Paula P; Johnson, Tricia J; Patel, Aloka L; Rossman, Beverly

2017-01-01

SYNOPSIS Best practices that translate the evidence for high dose HM feeding for preterm infants during the NICU hospitalization have been described in multiple studies but their implementation has been compromised largely due to economic and ideologic concerns. Although the rates of “any” HM feeding have increased over the last decade, efforts to help mothers maintain human milk provision through to NICU discharge have remained problematic throughout the world. Special emphasis should be placed on prioritizing the early lactation period of coming to volume so that mothers have sufficient HM volume to achieve their personal HM feeding goals. Finally, donor HM does not provide the same risk reduction as own mothers’ HM for multiple morbidities in preterm infants, providing needed evidence for channeling of limited resources into NICU programs that promote the use of mothers’ own HM. PMID:28159199

Evidence for pigmentary hematite on Mars based on optical, magnetic, and Moessbauer studies of superparamagnetic (nanocrystalline) hematite

NASA Technical Reports Server (NTRS)

Morris, Richard V.; Agresti, David G.; Newcomb, Jeffery A.; Shelfer, Tad D.; Lauer, Howard V., Jr.

1989-01-01

Samples containing variable amounts of superparamagnetic hematite (sp-Hm) were prepared by a method in which the sp-Hm particles were dispersed throughout larger particles of silica gel, and the optical and magnetic properties of these samples were compared with those of larger-diameter hematite (bulk-Hm). It is shown that the optical properties of sp-Hm are different from those of bulk-Hm. Implications of the results for mineralogical interpretations of spectral data for the Martian surface and its terrestrial analogues are discussed. It is concluded that features resulting from ferric iron in the Martian spectral data and the results of the Viking magnetic properties experiment are both consistent with hematite present as both sp-Hm and bulk-Hm; the hematite particles most likely occur in pigmentary form, i.e., as particles dispersed throughout the volume of a spectrally neutral material.

Comprehensive study of solid pharmaceutical tablets in visible, near infrared (NIR), and longwave infrared (LWIR) spectral regions using a rapid simultaneous ultraviolet/visible/NIR (UVN) + LWIR laser-induced breakdown spectroscopy linear arrays detection system and a fast acousto-optic tunable filter NIR spectrometer.

PubMed

Yang, Clayton S C; Jin, Feng; Swaminathan, Siva R; Patel, Sita; Ramer, Evan D; Trivedi, Sudhir B; Brown, Ei E; Hommerich, Uwe; Samuels, Alan C

2017-10-30

This is the first report of a simultaneous ultraviolet/visible/NIR and longwave infrared laser-induced breakdown spectroscopy (UVN + LWIR LIBS) measurement. In our attempt to study the feasibility of combining the newly developed rapid LWIR LIBS linear array detection system to existing rapid analytical techniques for a wide range of chemical analysis applications, two different solid pharmaceutical tablets, Tylenol arthritis pain and Bufferin, were studied using both a recently designed simultaneous UVN + LWIR LIBS detection system and a fast AOTF NIR (1200 to 2200 nm) spectrometer. Every simultaneous UVN + LWIR LIBS emission spectrum in this work was initiated by one single laser pulse-induced micro-plasma in the ambient air atmosphere. Distinct atomic and molecular LIBS emission signatures of the target compounds measured simultaneously in UVN (200 to 1100 nm) and LWIR (5.6 to 10 µm) spectral regions are readily detected and identified without the need to employ complex data processing. In depth profiling studies of these two pharmaceutical tablets without any sample preparation, one can easily monitor the transition of the dominant LWIR emission signatures from coating ingredients gradually to the pharmaceutical ingredients underneath the coating. The observed LWIR LIBS emission signatures provide complementary molecular information to the UVN LIBS signatures, thus adding robustness to identification procedures. LIBS techniques are more surface specific while NIR spectroscopy has the capability to probe more bulk materials with its greater penetration depth. Both UVN + LWIR LIBS and NIR absorption spectroscopy have shown the capabilities of acquiring useful target analyte spectral signatures in comparable short time scales. The addition of a rapid LWIR spectroscopic probe to these widely used optical analytical methods, such as NIR spectroscopy and UVN LIBS, may greatly enhance the capability and accuracy of the combined system for a comprehensive analysis.

A combined remote Raman and LIBS instrument for characterizing minerals with 532 nm laser excitation.

PubMed

Sharma, Shiv K; Misra, Anupam K; Lucey, Paul G; Lentz, Rachel C F

2009-08-01

The authors have developed an integrated remote Raman and laser-induced breakdown spectroscopy (LIBS) system for measuring both the Raman and LIBS spectra of minerals with a single 532 nm laser line of 35 mJ/pulse and 20 Hz. The instrument has been used for analyzing both Raman and LIBS spectra of carbonates, sulfates, hydrous and anhydrous silicates, and iron oxide minerals in air. These experiments demonstrate that by focusing a frequency-doubled 532 nm Nd:YAG pulsed laser beam with a 10x beam expander to a 529-microm diameter spot on a mineral surface located at 9 m, it is possible to measure simultaneously both the remote Raman and LIBS spectra of calcite, gypsum and olivine by adjusting the laser power electronically. The spectra of calcite, gypsum, and olivine contain fingerprint Raman lines; however, it was not possible to measure the remote Raman spectra of magnetite and hematite at 9 m because of strong absorption of 532 nm laser radiation and low intensities of Raman lines from these minerals. The remote LIBS spectra of both magnetite and hematite contain common iron emission lines but show difference in the minor amount of Li present in these two minerals. Remote Raman and LIBS spectra of a number of carbonates, sulfates, feldspars and phyllosilicates at a distance of 9 m were measured with a 532-nm laser operating at 35 mJ/pulse and by changing photon flux density at the sample by varying the spot diameter from 10 mm for Raman to 530 microm for LIBS measurements. The complementary nature of these spectra is highlighted and discussed. The combined Raman and LIBS system can also be re-configured to perform micro-Raman and micro-LIBS analyses, which have applications in trace/residue analysis and analysis of very small samples in the nano-gram range.

Complete cDNAs from Solenopsis invicta (Hymenoptera: Formicidae). --GenBank accession numbers: HM130684-HM130685.

USDA-ARS?s Scientific Manuscript database

2 new gene sequences were identified from workers of Solenopsis invicta, and submitted to the National Center for Biotechnology Information GenBank. GenBank accession numbers are HM130684-HM130685. This information will provide scientists with genetic tools to study the populations of this ant....

[Comparative investigation of underwater-LIBS using 532 and 1 064 nm lasers].

PubMed

Song, Jiao-Jian; Tian, Ye; Lu, Yuan; Li, Ying; Zheng, Rong-Er

2014-11-01

With the hope of applying laser induced breakdown spectroscopy (LIBS) to the ocean applications, the laser energy at 532 and 1 064 nm wavelength with 3 and 40 mj respectively was used, which was near their breakdown threshold. Extensive experimental investigations of LIBS from CaCl2 water solution were carried out in this paper using different laser wavelengths of 532 and 1 064 nm. The obtained results show that compared with the 532 nm laser, the 1 064 nm laser can induce the plasma in water with higher emission intensity and longer lifetime, while the reproducibility of LIBS signal under 1 064 nm laser is poorer. On the other hand, due to the different attenuation ratios of 532 and 1 064 nm laser energies in water, the LIBS signal of 1 064 nm laser decreases a lot within the transmission distance range 2-5 cm, while LIBS signal of 532 nm remains the same, because that the wavelength of 532 nm lies in the "transmission window" of the water solution. This study will provide valuable design considerations for the development of LIBS-sea system in near future.

Multi-Pulse Excitation for Underwater Analysis of Copper-Based Alloys Using a Novel Remote Laser-Induced Breakdown Spectroscopy (LIBS) System.

PubMed

Guirado, Salvador; Fortes, Francisco J; Laserna, J Javier

2016-04-01

In this work, the use of multi-pulse excitation has been evaluated as an effective solution to mitigate the preferential ablation of the most volatile elements, namely Sn, Pb, and Zn, observed during laser-induced breakdown spectroscopy (LIBS) analysis of copper-based alloys. The novel remote LIBS prototype used in this experiments featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The remote instrument is capable of performing chemical analysis of submersed materials up to a depth of 50 m. Laser-induced breakdown spectroscopy analysis was performed at air pressure settings simulating the conditions during a real subsea analysis. A set of five certified bronze standards with variable concentration of Cu, As, Sn, Pb, and Zn were used. In SP-LIBS, signal emission is strongly sensitive to ambient pressure. In this case, fractionation effect was observed. Multi-pulse excitation circumvents the effect of pressure over the quantitative analysis, thus avoiding the fractionation phenomena observed in single pulse LIBS. The use of copper as internal standard minimizes matrix effects and discrepancies due to variation in ablated mass. © The Author(s) 2016.

LOSS OF 5-HYDROXYMETHYLCYTOSINE IS AN EPIGENETIC HALLMARK OF MELANOMA

PubMed Central

Lian, Christine Guo; Xu, Yufei; Ceol, Craig; Wu, Feizhen; Larson, Allison; Dresser, Karen; Xu, Wenji; Tan, Li; Hu, Yeguang; Zhan, Qian; Lee, Chung-wei; Hu, Di; Lian, Bill Q.; Kleffel, Sonja; Yang, Yijun; Neiswender, James; Khorasani, Abraham J.; Fang, Rui; Lezcano, Cecilia; Duncan, Lyn M.; Scolyer, Richard A.; Thompson, John F.; Kakavand, Hojabr; Houvras, Yariv; Zon, Leonard; Mihm, Martin C.; Kaiser, Ursula B.; Schatton, Tobias; Woda, Bruce A.; Murphy, George F.; Shi, Yujiang G.

2013-01-01

SUMMARY DNA methylation at the 5-position of cytosine (5-mC) is a key epigenetic mark critical for various biological and pathological processes. 5-mC can be converted to 5-hydroxymethylcytosine (5-hmC) by the Ten-Eleven Translocation (TET) family of DNA hydroxylases. Here we report that “loss of 5-hmC” is an epigenetic hallmark of melanoma with diagnostic and prognostic implications. Genome-wide mapping of 5-hmC reveals loss of 5-hmC landscape in the melanoma epigenome. We show that down-regulation of Isocitrate Dehydrogenase 2 (IDH2) and TET family enzymes is likely one of the mechanisms underlying 5-hmC loss in melanoma. Rebuilding the 5-hmC landscape in melanoma cells by reintroducing active TET2 or IDH2 suppresses melanoma growth and increases tumor-free survival in animal models. Thus, our study reveals a critical function of 5-hmC in melanoma development and directly links the IDH and TET activity-dependent epigenetic pathway to 5-hmC-mediated suppression of melanoma progression, suggesting a new strategy for epigenetic cancer therapy. PMID:22980977

[Nitrogen and water cycling of typical cropland in the North China Plain].

PubMed

Pei, Hong-wei; Shen, Yan-jun; Liu, Chang-ming

2015-01-01

Intensive fertilization and irrigation associated increasing grain production has led to serious groundwater depletion and soil/water pollution in the North China Plain (NCP). Intensive agriculture changes the initial mass and energy balance, and also results in huge risks to the water/soil resources and food security regionally. Based on the research reports on the nitrogen cycle and water cycle in typical cropland (winter wheat and summer corn) in the NCP during the past 20 years, and the meteorological data, field experiments and surveys, we calculated the nitrogen cycle and water-cycle for this typical cropland. Annual total nitrogen input were 632 kg N . hm-2, including 523 kg N . hm-2 from commercial fertilizer, 74 kg N . hm-2 from manure, 23 kg N . hm-2 from atmosphere, and 12 kg N . hm-2 from irrigation. All of annual outputs summed to 532 kg N . hm-2 including 289 kg N . hm-2 for crop, 77 kg N . hm-2 staying in soil profile, leaching 104 kg N . hm-2, 52 kg N . hm-2 for ammonia volatilization, 10 kg N . hm-2 loss in nitrification and denitrification. Uncertainties of the individual cases and the summary process lead to the unbalance of nitrogen. For the dominant parts of the field water cycle, annual precipitation was 557 mm, irrigation was 340 mm, while 762 mm was for evapotranspiration and 135 mm was for deep percolation. Considering uncertainties in the nitrogen and water cycles, coupled experiments based on multi-disciplines would be useful for understanding mechanisms for nitrogen and water transfer processes in the soil-plant-atmosphere-continuum (SPAC) , and the interaction between nitrogen and water, as well as determining the critical threshold values for sustainability of soil and water resources in the NCP.

The ghrelin receptor agonist HM01 mimics the neuronal effects of ghrelin in the arcuate nucleus and attenuates anorexia-cachexia syndrome in tumor-bearing rats.

PubMed

Borner, Tito; Loi, Laura; Pietra, Claudio; Giuliano, Claudio; Lutz, Thomas A; Riediger, Thomas

2016-07-01

The gastric hormone ghrelin positively affects energy balance by increasing food intake and reducing energy expenditure. Ghrelin mimetics are a possible treatment against cancer anorexia-cachexia syndrome (CACS). This study aimed to characterize the action of the nonpeptidergic ghrelin receptor agonist HM01 on neuronal function, energy homeostasis and muscle mass in healthy rats and to evaluate its possible usefulness for the treatment of CACS in a rat tumor model. Using extracellular single-unit recordings, we tested whether HM01 mimics the effects of ghrelin on neuronal activity in the arcuate nucleus (Arc). Furthermore, we assessed the effect of chronic HM01 treatment on food intake (FI), body weight (BW), lean and fat volumes, and muscle mass in healthy rats. Using a hepatoma model, we investigated the possible beneficial effects of HM01 on tumor-induced anorexia, BW loss, muscle wasting, and metabolic rate. HM01 (10(-7)-10(-6) M) mimicked the effect of ghrelin (10(-8) M) by increasing the firing rate in 76% of Arc neurons. HM01 delivered chronically for 12 days via osmotic minipumps (50 μg/h) increased FI in healthy rats by 24%, paralleled by increased BW, higher fat and lean volumes, and higher muscle mass. Tumor-bearing rats treated with HM01 had 30% higher FI than tumor-bearing controls and were protected against BW loss. HM01 treatment resulted in higher muscle mass and fat mass. Moreover, tumor-bearing rats reduced their metabolic rate following HM01 treatment. Our studies substantiate the possible therapeutic usefulness of ghrelin receptor agonists like HM01 for the treatment of CACS and possibly other forms of disease-related anorexia and cachexia. Copyright © 2016 the American Physiological Society.

Superiority of automatic remote monitoring compared with in-person evaluation for scheduled ICD follow-up in the TRUST trial - testing execution of the recommendations

PubMed Central

Varma, Niraj; Michalski, Justin; Stambler, Bruce; Pavri, Behzad B.

2014-01-01

Aims To test recommended implantable cardioverter defibrillator (ICD) follow-up methods by ‘in-person evaluations’ (IPE) vs. ‘remote Home Monitoring’ (HM). Methods and results ICD patients were randomized 2:1 to automatic HM or to Conventional monitoring, with follow-up checks scheduled at 3, 6, 9, 12, and 15 months post-implant. Conventional patients were evaluated with IPE only. Home Monitoring patients were assessed remotely only for 1 year between 3 and 15 month evaluations. Adherence to follow-up was measured. HM and Conventional patients were similar (age 63 years, 72% male, left ventricular ejection fraction 29%, primary prevention 73%, DDD 57%). Conventional management suffered greater patient attrition during the trial (20.1 vs. 14.2% in HM, P = 0.007). Three month follow-up occurred in 84% in both groups. There was 100% adherence (5 of 5 checks) in 47.3% Conventional vs. 59.7% HM (P < 0.001). Between 3 and 15 months, HM exhibited superior (2.2×) adherence to scheduled follow-up [incidence of failed follow up was 146 of 2421 (6.0%) in HM vs. 145 of 1098 (13.2%) in Conventional, P < 0.001] and punctuality. In HM (daily transmission success rate median 91%), transmission loss caused only 22 of 2275 (0.97%) failed HM evaluations between 3 and 15 months; others resulted from clinic oversight. Overall IPE failure rate in Conventional [193 of 1841 (10.5%) exceeded that in HM [97 of 1484 (6.5%), P < 0.001] by 62%, i.e. HM patients remained more loyal to IPE when this was mandated. Conclusion Automatic remote monitoring better preserves patient retention and adherence to scheduled follow-up compared with IPE. Clinical trial registration NCT00336284. PMID:24595864

A Monte Carlo Study of Flux Ratios of Raman Scattered O VI Features at 6825 and 7082 Å in Symbiotic Stars

NASA Astrophysics Data System (ADS)

Lee, Young-Min; Lee, Dae-Sub; Chang, Seok-Jun; Heo, Jeong-Eun; Lee, Hee-Won; Hwang, Narae; Park, Byeong-Gon; Lee, Ho-Gyu

2016-12-01

Symbiotic stars are regarded as wide binary systems consisting of a hot white dwarf and a mass losing giant. They exhibit unique spectral features at 6825 and 7082 Å, which are formed via Raman scattering of O VI λλ 1032 and 1038 with atomic hydrogen. We adopt a Monte Carlo technique to generate the same number of O VI λ1032 and λ1038 line photons and compute the flux ratio F(6825)/F(7082) of these Raman scattered O VI features formed in neutral regions with a simple geometric shape as a function of H I column density N H I . In cylindrical and spherical neutral regions with the O VI source embedded inside, the flux ratio F(6825)/F(7082) shows an overall decrease from 3 to 1 as N H I increases in the range {10}22{--24} {{cm}}-2. In cases of slab geometry and other geometries with the O VI source outside the H I region, Rayleigh escape operates to lower the flux ratio considerably. For moderate values of {N}{{H}{{I}}}˜ {10}23 {{cm}}-2 the flux ratio behaves in a complicated way to exhibit a broad bump with a peak value of 3.5 in the case of a sphere geometry. We find that the ratio of Raman conversion efficiencies of O VI λλ 1032, 1038 ranges from 0.8 to 3.5. Our high resolution spectra of “D” type HM Sge and “S” type AG Dra obtained with the Canada-France-Hawaii Telescope show that the flux ratio F(6825)/F(7082) of AG Dra is significantly smaller than that of HM Sge, implying that “S” type symbiotics are characterized by higher N H I than “D” type symbiotics.

INFRARED SPECTROSCOPY OF SYMBIOTIC STARS. IX. D-TYPE SYMBIOTIC NOVAE

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

Hinkle, Kenneth H.; Joyce, Richard R.; Fekel, Francis C.

2013-06-10

Time-series spectra of the near-infrared 1.6 {mu}m region have been obtained for five of the six known D-type symbiotic novae. The spectra map the pulsation kinematics of the Mira component in the Mira-white dwarf binary system and provide the center-of-mass velocity for the Mira. No orbital motion is detected in agreement with previous estimates of orbital periods {approx}>100 yr and semimajor axes {approx}50 AU. The 1-5 {mu}m spectra of the Miras show line weakening during dust obscuration events. This results from scattering and continuum emission by 1000 K dust. In the heavily obscured HM Sge system the 4.6 {mu}m COmore » spectrum formed in 1000 K gas is seen in emission against an optically thick dust continuum. Spectral features that are typically produced in either the cool molecular region or the expanding circumstellar region of late-type stars cannot be detected in the D-symbiotic novae. This is in accord with the colliding wind model for interaction between the white dwarf and Mira. Arguments are presented that the 1000 K gas and dust are not Mira circumstellar material but are in the wind interaction region of the colliding winds. CO is the first molecule detected in this region. We suggest that dust condensing in the intershock region is the origin of the dust obscuration. This model explains variations in the obscuration. Toward the highly obscured Mira in HM Sge the dust zone is estimated to be {approx}0.1 AU thick. The intershock wind interaction zone appears thinnest in the most active systems. Drawing on multiple arguments masses are estimated for the system components. The Miras in most D-symbiotic novae have descended from intermediate mass progenitors. The large amount of mass lost from the Mira combined with the massive white dwarf companion suggests that these systems are supernova candidates. However, timescales and the number of objects make these rare events.« less

Randomized trial of human milk cream as a supplement to standard fortification of an exclusive human milk-based diet in infants 750-1250 g birth weight.

PubMed

Hair, Amy B; Blanco, Cynthia L; Moreira, Alvaro G; Hawthorne, Keli M; Lee, Martin L; Rechtman, David J; Abrams, Steven A

2014-11-01

To evaluate whether premature infants who received an exclusive human milk (HM)-based diet and a HM-derived cream supplement (cream) would have weight gain (g/kg/d) at least as good as infants receiving a standard feeding regimen (control). In a prospective noninferiority, randomized, unmasked study, infants with a birth weight 750-1250 g were randomly assigned to the control or cream group. The control group received mother's own milk or donor HM with donor HM-derived fortifier. The cream group received a HM-derived cream supplement if the energy density of the HM tested <20 kcal/oz using a near infrared HM analyzer. Infants were continued on the protocol until 36 weeks postmenstrual age. Primary outcomes included growth velocities and amount of donor HM-derived fortifier used. The hypothesis of noninferiority was established if the lower bound of the one-sided 95% CI for the difference in weight velocities exceeded -3 g/kg/day. There were no differences between groups in baseline demographics for the 78 infants studied except racial distribution (P = .02). The cream group (n = 39) had superior weight (14.0 ± 2.5 vs 12.4 ± 3.0 g/kg/d, P = .03) and length (1.03 ± 0.33 vs 0.83 ± 0.41 cm/wk, P = .02) velocity compared with the control group (n = 39). There were no significant differences in amount of fortifier used between study groups. The 1-sided 95% lower bound of the CI for the difference in mean velocity (cream-control) was 0.38 g/kg/d. Premature infants who received HM-derived cream to fortified HM had improved weight and length velocity compared with the control group. HM-derived cream should be considered an adjunctive supplement to an exclusive HM-based diet to improve growth rates in premature infants. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Role of Automatic Wireless Remote Monitoring Immediately Following ICD Implant: The Lumos-T Reduces Routine Office Device Follow-Up Study (TRUST) Trial.

PubMed

Varma, Niraj; Epstein, Andrew E; Schweikert, Robert; Michalski, Justin; Love, Charles J

2016-03-01

The incidence of unscheduled encounters and problem occurrence between ICD implant and first in-person evaluation (IPE) recommended at 12 weeks is unknown. Automatic remote home monitoring (HM) may be useful in this potentially unstable period. ICD patients were randomized 2:1 to HM enabled post-implant (n = 908) or to conventional monitoring (CM; n = 431). Groups were compared between implant and prior to first scheduled IPE for IPE incidence, causes, and actionability (reprogramming, system revision, medication changes) and event detection time. HM and CM patients were similar (mean age 63 years, 72% male, LVEF 29%, primary prevention 73%, DDD 57%). In the post-implant interval assessed (HM 100 ± 21.3 days vs. CM 101 ± 20.8 days, P = 0.54), 85.4% (776/908) HM patients and 87.7% CM (378/431) patients had no cause for IPE (P = 0.31). When IPE occurred, actionability in HM (64/177 [36.2%]) was greater versus CM (15/62 [24.2%], P = 0.12). Actionable items were discovered sooner with HM (P = 0.025). Device reprogramming or lead revision was triggered following 53/177 (29.9%) IPEs in HM versus 9/62 (14.5%) in CM (P = 0.018). Arrhythmia detection was enhanced by HM: 276 atrial and ventricular episodes were detected in 135 follow-ups in contrast to CM (65 episodes at 17 IPEs). More silent arrhythmic episodes were discovered by HM (7.2% vs. 1.5% [P = 0.15]). Since 27/42 (64.3%) IPEs driven by HM alerts were actionable, event notification was a valuable method for problem detection. Importantly, HM did not increase incidence of non-actionable IPEs (P = 0.72). Activation of automatic remote monitoring should be encouraged soon post-ICD implant. © 2015 Wiley Periodicals, Inc.

Novel high-density packaging of solid state diode pumped eye-safe laser for LIBS

NASA Astrophysics Data System (ADS)

Bares, Kim; Torgerson, Justin; McNeil, Laine; Maine, Patrick; Patterson, Steve

2018-02-01

Laser-Induced Breakdown Spectroscopy (LIBS) has proven to be a useful research tool for material analysis for decades. However, because of the amount of energy required in a few nanosecond pulse to generate a stable and reliable LIBS signal, the lasers are often large and inefficient, relegating their implementation to research facilities, factory floors, and assembly lines. Small portable LIBS systems are now possible without having to compromise on energy needs by leveraging off of advances in high-density packaging of electronics, opto-mechanics, and highly efficient laser resonator architecture. This paper explores the integration of these techniques to achieve a mJ class eye-safe LIBS laser source, while retaining a small, light-weight package suitable for handheld systems.

Preliminary design of laser-induced breakdown spectroscopy for proto-Material Plasma Exposure eXperiment

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

Shaw, G., E-mail: shawgc@ornl.gov; University of Tennessee, Knoxville, Tennessee 37996; Martin, M. Z.

2014-11-15

Laser-induced breakdown spectroscopy (LIBS) is a technique for measuring surface matter composition. LIBS is performed by focusing laser radiation onto a target surface, ablating the surface, forming a plasma, and analyzing the light produced. LIBS surface analysis is a possible diagnostic for characterizing plasma-facing materials in ITER. Oak Ridge National Laboratory has enabled the initial installation of a laser-induced breakdown spectroscopy diagnostic on the prototype Material-Plasma Exposure eXperiment (Proto-MPEX), which strives to mimic the conditions found at the surface of the ITER divertor. This paper will discuss the LIBS implementation on Proto-MPEX, preliminary design of the fiber optic LIBS collectionmore » probe, and the expected results.« less

Joint analyses by laser-induced breakdown spectroscopy (LIBS) and Raman spectroscopy at stand-off distances.

PubMed

Wiens, Roger C; Sharma, Shiv K; Thompson, Justin; Misra, Anupam; Lucey, Paul G

2005-08-01

Raman spectroscopy and laser-induced breakdown spectroscopy (LIBS) of solid samples have both been shown to be feasible with sample-to-instrument distances of many meters. The two techniques are very useful together, as the combination of elemental compositions from LIBS and molecular vibrational information from Raman spectroscopy strongly complement each other. Remote LIBS and Raman spectroscopy spectra were taken together on a number of mineral samples including sulfates, carbonates and silicates at a distance of 8.3 m. The complementary nature of these spectra is highlighted and discussed. A factor of approximately 20 difference in intensity was observed between the brightest Raman line of calcite, at optimal laser power, and the brighter Ca I LIBS emission line measured with 55 mJ/pulse laser power. LIBS and Raman spectroscopy have several obstacles to devising a single instrument capable of both techniques. These include the differing spectral ranges and required detection sensitivity. The current state of technology in these areas is discussed.

LIBS coupled with ICP/OES for the spectral analysis of betel leaves

NASA Astrophysics Data System (ADS)

Rehan, I.; Rehan, K.; Sultana, S.; Khan, M. Z.; Muhammad, R.

2018-05-01

Laser-induced breakdown spectroscopy (LIBS) system was optimized and was applied for the elemental analysis and exposure of the heavy metals in betel leaves in air. Pulsed Nd:YAG (1064 nm) in conjunction with a suitable detector (LIBS 2000+, Ocean Optics, Inc) having the optical resolution of 0.06 nm was used to record the emission spectra from 200 to 720 nm. Elements like Al, Ba, Ca, Cr, Cu, P, Fe, K, Mg, Mn, Na, P, S, Sr, and Zn were found to be present in the samples. The abundances of observed elements were calculated through normalized calibration curve method, integrated intensity ratio method, and calibration free-LIBS approach. Quantitative analyses were accomplished under the assumption of local thermodynamic equilibrium (LTE) and optically thin plasma. LIBS findings were validated by comparing its results with the results obtained using a typical analytical technique of inductively coupled plasma-optical emission spectroscopy (ICP/OES). Limit of detection (LOD) of the LIBS system was also estimated for heavy metals.

libSRES: a C library for stochastic ranking evolution strategy for parameter estimation.

PubMed

Ji, Xinglai; Xu, Ying

2006-01-01

Estimation of kinetic parameters in a biochemical pathway or network represents a common problem in systems studies of biological processes. We have implemented a C library, named libSRES, to facilitate a fast implementation of computer software for study of non-linear biochemical pathways. This library implements a (mu, lambda)-ES evolutionary optimization algorithm that uses stochastic ranking as the constraint handling technique. Considering the amount of computing time it might require to solve a parameter-estimation problem, an MPI version of libSRES is provided for parallel implementation, as well as a simple user interface. libSRES is freely available and could be used directly in any C program as a library function. We have extensively tested the performance of libSRES on various pathway parameter-estimation problems and found its performance to be satisfactory. The source code (in C) is free for academic users at http://csbl.bmb.uga.edu/~jix/science/libSRES/

Standoff Laser-Induced Breakdown Spectroscopy (LIBS) Using a Miniature Wide Field of View Spatial Heterodyne Spectrometer with Sub-Microsteradian Collection Optics.

PubMed

Barnett, Patrick D; Lamsal, Nirmal; Angel, S Michael

2017-04-01

A spatial heterodyne spectrometer (SHS) is described for standoff laser-induced breakdown spectroscopy (LIBS) measurements. The spatial heterodyne LIBS spectrometer (SHLS) is a diffraction grating based interferometer with no moving parts that offers a very large field of view, high light throughput, and high spectral resolution in a small package. The field of view of the SHLS spectrometer is shown to be ∼1° in standoff LIBS measurements. In the SHLS system described here, the collection aperture was defined by the 10 mm diffraction gratings in the SHS and standoff LIBS measurements were made up to 20 m with no additional collection optics, corresponding to a collection solid angle of 0.2 μsr, or f/2000, and also using a small telescope to increase the collection efficiency. The use of a microphone was demonstrated to rapidly optimize laser focus for 20 m standoff LIBS measurements.

Effective laser-induced breakdown spectroscopy (LIBS) detection using double pulse at optimum configuration.

PubMed

Choi, Soo Jin; Yoh, Jack J

2011-08-01

A short laser pulse is irradiated on a sample to create a highly energetic plasma that emits light of a specific peak wavelength according to the material. By identifying different peaks for the analyzed samples, their chemical composition can be rapidly determined. The characteristics of the laser-induced breakdown spectroscopy (LIBS) plasma are strongly dependent on the ambient conditions. Research aimed at enhancing LIBS intensity is of great benefit in advancing LIBS for the exploration of harsh environments. By using double-pulse LIBS, the signal intensity of Al and Ca lines was enhanced by five times compared to the single-pulse signal. Also, the angles of the target and detector are adjusted to simulate samples of arbitrary shape. We verified that there exists an optimal angle at which specific elements of a test sample may be detected with stronger signal intensity. We provide several optimum configurations for the LIBS system for maximizing the signal intensity for the analysis of a nonstandard aluminum sample.

Study of different concentric rings inside gallstones with LIBS.

PubMed

Pathak, Ashok Kumar; Singh, Vivek Kumar; Rai, Nilesh Kumar; Rai, Awadhesh Kumar; Rai, Pradeep Kumar; Rai, Pramod Kumar; Rai, Suman; Baruah, G D

2011-07-01

Gallstones obtained from patients from the north-east region of India (Assam) were studied using laser-induced breakdown spectroscopy (LIBS) technique. LIBS spectra of the different layers (in cross-section) of the gallstones were recorded in the spectral region 200-900 nm. Several elements, including calcium, magnesium, manganese, copper, silicon, phosphorus, iron, sodium and potassium, were detected in the gallstones. Lighter elements, including carbon, hydrogen, nitrogen and oxygen were also detected, which demonstrates the superiority of the LIBS technique over other existing analytical techniques. The LIBS technique was applied to investigate the evolution of C(2) swan bands and CN violet bands in the LIBS spectra of the gallstones in air and an argon atmosphere. The different layers (dark and light layers) of the gallstones were discriminated on the basis of the presence and intensities of the spectral lines for carbon, hydrogen, nitrogen, oxygen and copper. An attempt was also made to correlate the presence of major and minor elements in the gallstones with the common diet of the population of Assam.

Cyber Operational Architecture Training System Cyber for All

DTIC Science & Technology

2015-12-30

Ingenia Services, Inc. Camp H.M. Smith , HI Camp H.M. Smith , HI william.d.wells1.ctr@pacom.mil derek.bryan.ctr@pacom.mil ABSTRACT Current...War Innovation Center USPACOM J81 / Ingenia Services, Inc. Camp H.M. Smith , HI Camp H.M. Smith , HI william.d.wells1.ctr@pacom.mil derek.bryan.ctr

46 CFR 174.055 - Calculation of wind heeling moment (Hm).

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Calculation of wind heeling moment (Hm). 174.055 Section... Units § 174.055 Calculation of wind heeling moment (Hm). (a) The wind heeling moment (Hm) of a unit in a given normal operating condition or severe storm condition is the sum of the individual wind heeling...

In-vitro analysis of early calcification in aortic valvular interstitial cells using Laser-Induced Breakdown Spectroscopy (LIBS).

PubMed

Davari, Seyyed Ali; Masjedi, Shirin; Ferdous, Zannatul; Mukherjee, Dibyendu

2018-01-01

Calcific aortic valve disease (CAVD) is a major cardiovascular disorder caused by osteogenic differentiation of valvular interstitial cells (VICs) within aortic valves. Conventional methods like colorimetric assays and histology fail to detect small calcium depositions during in-vitro VIC cultures. Laser-induced breakdown spectroscopy (LIBS) is a robust analytical tool used for inorganic materials characterizations, but relatively new to biomedical applications. We employ LIBS, for the first time, for quantitative in-vitro detection of calcium depositions in VICs at various osteogenic differentiation stages. VICs isolated from porcine aortic valves were cultured in osteogenic media over various days. Colorimetric calcium assays based on arsenazo dye and Von Kossa staining measured the calcium depositions within VICs. Simultaneously, LIBS signatures for Ca I (422.67 nm) atomic emission lines were collected for estimating calcium depositions in lyophilized VIC samples. Our results indicate excellent linear correlation between the calcium assay and our LIBS measurements. Furthermore, unlike the assay results, the LIBS results could resolve calcium signals from cell samples with as early as 2 days of osteogenic culture. Quantitatively, the LIBS measurements establish the limit of detection for calcium content in VICs to be ∼0.17±0.04 μg which indicates a 5-fold improvement over calcium assay. Picture: Quantitative LIBS enables in-vitro analysis for early stage detection of calcium deposition within aortic valvular interstitial cells (VICs). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Resistor Susceptibility Survey

DTIC Science & Technology

1976-11-01

SATIN IV ATTN: DCKE, L. Staples ATTN. YWES ATTN XRE-Surv. ATTN- MCAE, Lt Col Sparks ATTN: XRP , Maj Gingrich Sandia Lab. ATTN 3141 ATTN E...Diamond Lab. ATTN: Lib. HQ USAF ATTN: XOOWD AFSC Tech. Lib. ATTN: DLCAW ATTN: XRP ! Sperry Rand Fit. Sys. Div. ATTN: Tech. Lib. ATTN: D

Study of Pulsations in the Atmosphere of the roAp star HD 137949

NASA Astrophysics Data System (ADS)

Sachkov, M.; Hareter, M.; Ryabchikova, T.; Wade, G.; Kochukhov, O.; Weiss, W. W.

The roAp star HD 137949 (33 Lib) shows the most complex pulsational behaviour among all roAp stars. Mkrtichian et al. (2003) found nearly anti-phase pulsations of Nd II and Nd III lines, which they attribute to the presence of a pulsation node high in the atmosphere of HD 137949. This was confirmed by Kurtz at al. (2005), who also find that in some REE lines the main frequency, corresponding to 8.27 min, and its harmonic have almost equal RV amplitudes. Based on high accuracy observations Ryabchikova et al. (2007a) studied pulsational characteristics of the HD 137949 atmosphere in detail. In general, spectroscopy provides 3D resolution of modes and allows to search for the photometrically undetectable frequencies. The high-accuracy space photometry provides very high-precision measurements of detected pulsation frequencies and enables an accurate phasing of multi-site spectroscopic data. A combination of simultaneous spectroscopy and photometry represents the most sophisticated asteroseismic dataset for any roAp star. In 2009 the star HD 137949 became a target of an intense observing campaign that combined ground-based spectroscopy with space photometry, obtained with the MOST satellite. We collected 780 spectra using the ESPaDOnS spectrograph mounted on the 3.6 m CFHT telescope; 374 spectra were obtained with the FIES spectrograph mounted on the 2.56-m NOT to perform the time-resolved spectroscopy of HD 137949. In addition, we used 111 UVES spectra (2004) from the ESO archive to check the mode stability. The frequency analysis of the new radial velocity (RV) measurements confirmed the previously reported frequency pattern (two frequencies and the first harmonic of the main frequency), and revealed an additional frequency at 1.991 mHz. The new frequency solution fits perfectly the RV variations from the 2004 and 2009 observational sets providing a strong support for the p-mode stability in the roAp star HD 137949 for at least 5 years.

Alleviation of Heavy Metal Stress in Plants and Remediation of Soil by Rhizosphere Microorganisms

PubMed Central

Mishra, Jitendra; Singh, Rachna; Arora, Naveen K.

2017-01-01

Increasing concentration of heavy metals (HM) due to various anthropogenic activities is a serious problem. Plants are very much affected by HM pollution particularly in contaminated soils. Survival of plants becomes tough and its overall health under HM stress is impaired. Remediation of HM in contaminated soil is done by physical and chemical processes which are costly, time-consuming, and non-sustainable. Metal–microbe interaction is an emerging but under-utilized technology that can be exploited to reduce HM stress in plants. Several rhizosphere microorganisms are known to play essential role in the management of HM stresses in plants. They can accumulate, transform, or detoxify HM. In general, the benefit from these microbes can have a vast impact on plant’s health. Plant–microbe associations targeting HM stress may provide another dimension to existing phytoremediation and rhizoremediation uses. In this review, applied aspects and mechanisms of action of heavy metal tolerant-plant growth promoting (HMT-PGP) microbes in ensuring plant survival and growth in contaminated soils are discussed. The use of HMT-PGP microbes and their interaction with plants in remediation of contaminated soil can be the approach for the future. This low input and sustainable biotechnology can be of immense use/importance in reclaiming the HM contaminated soils, thus increasing the quality and yield of such soils. PMID:28932218

Human milk miRNAs primarily originate from the mammary gland resulting in unique miRNA profiles of fractionated milk

PubMed Central

Alsaweed, Mohammed; Lai, Ching Tat; Hartmann, Peter E.; Geddes, Donna T.; Kakulas, Foteini

2016-01-01

Human milk (HM) contains regulatory biomolecules including miRNAs, the origin and functional significance of which are still undetermined. We used TaqMan OpenArrays to profile 681 mature miRNAs in HM cells and fat, and compared them with maternal peripheral blood mononuclear cells (PBMCs) and plasma, and bovine and soy infant formulae. HM cells and PBMCs (292 and 345 miRNAs, respectively) had higher miRNA content than HM fat and plasma (242 and 219 miRNAs, respectively) (p < 0.05). A strong association in miRNA profiles was found between HM cells and fat, whilst PBMCs and plasma were distinctly different to HM, displaying marked inter-individual variation. Considering the dominance of epithelial cells in mature milk of healthy women, these results suggest that HM miRNAs primarily originate from the mammary epithelium, whilst the maternal circulation may have a smaller contribution. Our findings demonstrate that unlike infant formulae, which contained very few human miRNA, HM is a rich source of lactation-specific miRNA, which could be used as biomarkers of the performance and health status of the lactating mammary gland. Given the recently identified stability, uptake and functionality of food- and milk-derived miRNA in vivo, HM miRNA are likely to contribute to infant protection and development. PMID:26854194

Characterization of human liver cytochrome P-450 enzymes involved in the O-demethylation of a new P-glycoprotein inhibitor HM-30181.

PubMed

Paek, In Bok; Kim, Sung Yeon; Kim, Maeng Sup; Kim, John; Lee, Gwansun; Lee, Hye Suk

2007-08-01

HM-30181, 4-oxo-4H-chromene-2-carboxylic acid [2-(2-{4-[2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl)-ethyl]-phenyl}-2H-tetrazol-5-yl)-4,5-dimethoxy-phenyl]-amide, is a new P-glycoprotein inhibitor with the potential to increase the cytotoxic activity of orally coadministered paclitaxel. This study was performed to characterize human cytochrome P-450 (CYP) enzymes involved in the metabolism of HM-30181 to 4- or 5-O-desmethyl-HM-30181 (M2) and 6- or 7-O-desmethyl-HM-30181 (M3) and to investigate the inhibitory potential of HM-30181 on CYP enzymes in human liver microsomes. CYP3A4 was identified as the major isozyme responsible for the O-demethylation of HM-30181 to M2 and M3 based on the correlation analysis, chemical inhibition and immuno-inhibition study and metabolism in cDNA-expressed human CYP isozymes. HM-30181 itself had no inhibitory effects on CYPs 1A2, 2A6, 2C8, 2C9, 2C19, 2D6, and 3A4 in human liver microsomes, suggesting the possibility that the pharmacokinetics of HM-30181 could be changed with coadministration of known CYP3A4 inducers or inhibitors.

Metabolism of a new P-glycoprotein inhibitor HM-30181 in rats using liquid chromatography/electrospray mass spectrometry.

PubMed

Paek, In Bok; Ji, Hye Young; Kim, Maeng Sup; Lee, Gwansun; Lee, Hye Suk

2006-01-01

HM-30181, 4-oxo-4H-chromene-2-carboxylic acid, [2-(2-{4-[2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl)-ethyl]-phenyl}-2H-tetrazol-5-yl)-4,5-dimethoxyphenyl]amide, is a new P-glycoprotein inhibitor. This study was performed to identify the in vitro and in vivo metabolic pathway of HM-30181 in rats. Rat liver microsomal incubation of HM-30181 in the presence of NADPH resulted in the formation of four metabolites, M1-M4. M1 and M2 were identified as 2-(2-{4-[2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl)-ethyl]-phenyl}-2H-tetrazol-5-yl)-4,5-dimethoxyaniline and 4- or 5-O-desmethyl-HM-30181, respectively, on the basis of liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis with the synthesized authentic standards. M3 and M4 were suggested to be 6- or 7-O-desmethyl-HM-30181 and hydroxy-HM-30181, respectively. These in vitro metabolites were also detected in feces and urine samples after an intravenous administration of HM-30181 to male rats. The metabolic routes for HM-30181 were O-demethylation of the methoxy group to M2 and M3, hydrolysis of the amide group to M1, and hydroxylation to M4. Copyright 2006 John Wiley & Sons, Ltd.

Human milk miRNAs primarily originate from the mammary gland resulting in unique miRNA profiles of fractionated milk.

PubMed

Alsaweed, Mohammed; Lai, Ching Tat; Hartmann, Peter E; Geddes, Donna T; Kakulas, Foteini

2016-02-08

Human milk (HM) contains regulatory biomolecules including miRNAs, the origin and functional significance of which are still undetermined. We used TaqMan OpenArrays to profile 681 mature miRNAs in HM cells and fat, and compared them with maternal peripheral blood mononuclear cells (PBMCs) and plasma, and bovine and soy infant formulae. HM cells and PBMCs (292 and 345 miRNAs, respectively) had higher miRNA content than HM fat and plasma (242 and 219 miRNAs, respectively) (p < 0.05). A strong association in miRNA profiles was found between HM cells and fat, whilst PBMCs and plasma were distinctly different to HM, displaying marked inter-individual variation. Considering the dominance of epithelial cells in mature milk of healthy women, these results suggest that HM miRNAs primarily originate from the mammary epithelium, whilst the maternal circulation may have a smaller contribution. Our findings demonstrate that unlike infant formulae, which contained very few human miRNA, HM is a rich source of lactation-specific miRNA, which could be used as biomarkers of the performance and health status of the lactating mammary gland. Given the recently identified stability, uptake and functionality of food- and milk-derived miRNA in vivo, HM miRNA are likely to contribute to infant protection and development.

46 CFR 174.055 - Calculation of wind heeling moment (Hm).

Code of Federal Regulations, 2014 CFR

2014-10-01

... lateral resistance of the underwater hull to the center of wind pressure on “A”. (c) When calculating “A... 46 Shipping 7 2014-10-01 2014-10-01 false Calculation of wind heeling moment (Hm). 174.055 Section... Units § 174.055 Calculation of wind heeling moment (Hm). (a) The wind heeling moment (Hm) of a unit in a...

46 CFR 174.055 - Calculation of wind heeling moment (Hm).

Code of Federal Regulations, 2012 CFR

2012-10-01

... lateral resistance of the underwater hull to the center of wind pressure on “A”. (c) When calculating “A... 46 Shipping 7 2012-10-01 2012-10-01 false Calculation of wind heeling moment (Hm). 174.055 Section... Units § 174.055 Calculation of wind heeling moment (Hm). (a) The wind heeling moment (Hm) of a unit in a...

In vitro activities of kappa-carrageenan isolated from red marine alga Hypnea musciformis: Antimicrobial, anticancer and neuroprotective potential.

PubMed

Souza, Ricardo Basto; Frota, Annyta Fernandes; Silva, Joana; Alves, Celso; Neugebauer, Agnieszka Zofia; Pinteus, Susete; Rodrigues, José Ariévilo Gurgel; Cordeiro, Edna Maria Silva; de Almeida, Raimundo Rafael; Pedrosa, Rui; Benevides, Norma Maria Barros

2018-06-01

This study assessed the antioxidant, antimicrobial, anticancer and neuroprotective activities of the kappa(k)-carrageenan isolated from the red alga Hypnea musciformis (Hm-SP). The chemical spectrum of the k-carrageenan from Hm-SP was confirmed by Fourier transform infrared (FT-IR) spectroscopy. Hm-SP revealed an antibacterial and antifungal action against Staphylococcus aureus and Candida albicans, respectively. Hm-SP did not promoted cytotoxic effects against Human breast cancer (MCF-7) and Human neuroblastoma (SH-SY5Y) cell-lines. However, it was observed a significant reduction of the cellular proliferation capacity in these cancer cells in presence of the Hm-SP. Furthermore, Hm-SP showed neuroprotective activity in 6-hydroxydopamine-induced neurotoxicity on SH-SY5Y cells by modulation of the mitochondria transmembrane potential and reducing Caspase 3 activity. In addition, Hm-SP demonstrates low antioxidant potential and did not induce significant cytotoxic effects or changes in the cell proliferation on Balb/c 3T3 mouse fibroblast cell-line. In summary, our data suggest that Hm-SP shows antimicrobial, anticancer and neuprotective activities. Copyright © 2018 Elsevier B.V. All rights reserved.

Role of Ethylene and Its Cross Talk with Other Signaling Molecules in Plant Responses to Heavy Metal Stress1

PubMed Central

Thao, Nguyen Phuong; Khan, M. Iqbal R.; Thu, Nguyen Binh Anh; Hoang, Xuan Lan Thi; Asgher, Mohd; Khan, Nafees A.; Tran, Lam-Son Phan

2015-01-01

Excessive heavy metals (HMs) in agricultural lands cause toxicities to plants, resulting in declines in crop productivity. Recent advances in ethylene biology research have established that ethylene is not only responsible for many important physiological activities in plants but also plays a pivotal role in HM stress tolerance. The manipulation of ethylene in plants to cope with HM stress through various approaches targeting either ethylene biosynthesis or the ethylene signaling pathway has brought promising outcomes. This review covers ethylene production and signal transduction in plant responses to HM stress, cross talk between ethylene and other signaling molecules under adverse HM stress conditions, and approaches to modify ethylene action to improve HM tolerance. From our current understanding about ethylene and its regulatory activities, it is believed that the optimization of endogenous ethylene levels in plants under HM stress would pave the way for developing transgenic crops with improved HM tolerance. PMID:26246451

The effect of nutrient media water purity on LIBS based identification of bacteria

USDA-ARS?s Scientific Manuscript database

Single pulse laser induced breakdown spectroscopy (LIBS) is used as the basis for discrimination between 3 genera of Gram-negative bacteria and 2 genera of gram-positive bacteria representing pathogenic threats commonly found in poultry processing rinse waters. Because LIBS-based discrimination reli...

Surface characterization of stainless HP-40 steel using laser induced μ-breakdown spectroscopy (μ -LIBS)

NASA Astrophysics Data System (ADS)

Pinto, M.; Calderón, X.; Mejía Ospino, E.; Cabanzo, R.; Poveda, Juan C.

2016-02-01

In the present study, optical microscopy in stereoscopic mode coupled to laser- induced p-breakdown spectroscopy (μ-LIBS) was applied for analysing HP-40 steel samples. microLIBS (μ-LIBS) is a new growing area that employs low energy laser pulses for the generation of plasma emission, which allow the realization of localized microanalysis [1]. This new LIBS instrument was used for the surface characterization of the steel samples in the spectral range from 356 to 401nm. Elements such as Cr, Ni, Fe, Nb, Pb, Mo, C, Mn and Si in the steel samples were investigated. The results allowed the construction of elemental distribution profiles of the samples. Complementary the HP-40 steel samples were superficially characterized by Scanning Electron Microscope (SEM).

Green-synthetized silver nanoparticles for Nanoparticle-Enhanced Laser Induced Breakdown Spectroscopy (NELIBS) using a mobile instrument

NASA Astrophysics Data System (ADS)

Poggialini, F.; Campanella, B.; Giannarelli, S.; Grifoni, E.; Legnaioli, S.; Lorenzetti, G.; Pagnotta, S.; Safi, A.; Palleschi, V.

2018-03-01

When compared to other analytical techniques, LIBS shows relatively low precision and, generally, high Limits of Detection (LODs). Until recently, the attempts in improving the LIBS performances have been based on the use of more stable/powerful lasers, high sensitivity detectors or controlled environmental parameters. This can hinder the competitiveness of LIBS by increasing the instrumental setup cost and the difficulty of operation. Sample treatment has proved to be a viable and simple way to increase the LIBS signal; in particular, the Nanoparticle-Enhanced Laser Induced Breakdown Spectroscopy (NELIBS) methodology uses a deposition of metal nanoparticles on the sample to greatly increase the emission of the LIBS plasma. In this work, we used a simple, fast, "green" and low-cost method to synthetize silver nanoparticles by using coffee extract as reducing agents for a silver nitrate solution. This allowed us to obtain nanoparticles of about 25 nm in diameter. We then explored the application of such nanoparticles to the NELIBS analysis of metallic samples with a mobile LIBS instrument. By adjusting the laser parameters and optimizing the sample preparation procedure, we obtained a NELIBS signal that is 4 times the LIBS one. This showed the potential of green-synthetized nanoparticle for NELIBS applications and suggests the possibility of an in-situ application of the technique.

Analysis of heterogeneous gallstones using laser-induced breakdown spectroscopy (LIBS) and wavelength dispersive X-ray fluorescence (WD-XRF).

PubMed

Jaswal, Brij Bir S; Kumar, Vinay; Sharma, Jitendra; Rai, Pradeep K; Gondal, Mohammed A; Gondal, Bilal; Singh, Vivek K

2016-04-01

Laser-induced breakdown spectroscopy (LIBS) is an emerging analytical technique with numerous advantages such as rapidity, multi-elemental analysis, no specific sample preparation requirements, non-destructiveness, and versatility. It has been proven to be a robust elemental analysis tool attracting interest because of being applied to a wide range of materials including biomaterials. In this paper, we have performed spectroscopic studies on gallstones which are heterogeneous in nature using LIBS and wavelength dispersive X-ray fluorescence (WD-XRF) techniques. It has been observed that the presence and relative concentrations of trace elements in different kind of gallstones (cholesterol and pigment gallstones) can easily be determined using LIBS technique. From the experiments carried out on gallstones for trace elemental mapping and detection, it was found that LIBS is a robust tool for such biomedical applications. The stone samples studied in the present paper were classified using the Fourier transform infrared (FTIR) spectroscopy. WD-XRF spectroscopy has been applied for the qualitative and quantitative analysis of major and trace elements present in the gallstone which was compared with the LIBS data. The results obtained in the present paper show interesting prospects for LIBS and WD-XRF to study cholelithiasis better.

Rapid detection of soils contaminated with heavy metals and oils by laser induced breakdown spectroscopy (LIBS).

PubMed

Kim, Gibaek; Kwak, Jihyun; Kim, Ki-Rak; Lee, Heesung; Kim, Kyoung-Woong; Yang, Hyeon; Park, Kihong

2013-12-15

A laser induced breakdown spectroscopy (LIBS) coupled with the chemometric method was applied to rapidly discriminate between soils contaminated with heavy metals or oils and clean soils. The effects of the water contents and grain sizes of soil samples on LIBS emissions were also investigated. The LIBS emission lines decreased by 59-75% when the water content increased from 1.2% to 7.8%, and soil samples with a grain size of 75 μm displayed higher LIBS emission lines with lower relative standard deviations than those with a 2mm grain size. The water content was found to have a more pronounced effect on the LIBS emission lines than the grain size. Pelletizing and sieving were conducted for all samples collected from abandoned mining areas and military camp to have similar water contents and grain sizes before being analyzed by the LIBS with the chemometric analysis. The data show that three types of soil samples were clearly discerned by using the first three principal components from the spectral data of soil samples. A blind test was conducted with a 100% correction rate for soil samples contaminated with heavy metals and oil residues. Copyright © 2013 Elsevier B.V. All rights reserved.

Direct measurements of sample heating by a laser-induced air plasma in pre-ablation spark dual-pulse laser-induced breakdown spectroscopy (LIBS).

PubMed

Register, Janna; Scaffidi, Jonathan; Angel, S Michael

2012-08-01

Direct measurements of temperature changes were made using small thermocouples (TC), placed near a laser-induced air plasma. Temperature changes up to ~500 °C were observed. From the measured temperature changes, estimates were made of the amount of heat absorbed per unit area. This allowed calculations to be made of the surface temperature, as a function of time, of a sample heated by the air plasma that is generated during orthogonal pre-ablation spark dual-pulse (DP) LIBS measurements. In separate experiments, single-pulse (SP) LIBS emission and sample ablation rate measurements were performed on nickel at sample temperatures ranging from room temperature to the maximum surface temperature that was calculated using the TC measurement results (500 °C). A small, but real sample temperature-dependent increase in both SP LIBS emission and the rate of sample ablation was found for nickel samples heated up to 500 °C. Comparison of DP LIBS emission enhancement values for bulk nickel samples at room temperature versus the enhanced SP LIBS emission and sample ablation rates observed as a function of increasing sample temperature suggests that sample heating by the laser-induced air plasma plays only a minor role in DP LIBS emission enhancement.

Homogeneity testing and quantitative analysis of manganese (Mn) in vitrified Mn-doped glasses by laser-induced breakdown spectroscopy (LIBS)

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

Unnikrishnan, V. K.; Nayak, Rajesh; Kartha, V. B.

2014-09-15

Laser-induced breakdown spectroscopy (LIBS), an atomic emission spectroscopy method, has rapidly grown as one of the best elemental analysis techniques over the past two decades. Homogeneity testing and quantitative analysis of manganese (Mn) in manganese-doped glasses have been carried out using an optimized LIBS system employing a nanosecond ultraviolet Nd:YAG laser as the source of excitation. The glass samples have been prepared using conventional vitrification methods. The laser pulse irradiance on the surface of the glass samples placed in air at atmospheric pressure was about 1.7×10{sup 9} W/cm{sup 2}. The spatially integrated plasma emission was collected and imaged on tomore » the spectrograph slit using an optical-fiber-based collection system. Homogeneity was checked by recording LIBS spectra from different sites on the sample surface and analyzing the elemental emission intensities for concentration determination. Validation of the observed LIBS results was done by comparison with scanning electron microscope- energy dispersive X-ray spectroscopy (SEM-EDX) surface elemental mapping. The analytical performance of the LIBS system has been evaluated through the correlation of the LIBS determined concentrations of Mn with its certified values. The results are found to be in very good agreement with the certified concentrations.« less

Simple and cost-effective fluorescent labeling of 5-hydroxymethylcytosine

NASA Astrophysics Data System (ADS)

Shahal, Tamar; Green, Ori; Hananel, Uri; Michaeli, Yael; Shabat, Doron; Ebenstein, Yuval

2016-12-01

The nucleobase 5-hydroxymethylcytosine (5-hmC), a modified form of cytosine, is an important epigenetic mark related to regulation of gene expression. 5-hmC levels are highly dynamic during early development and are modulated during the progression of neurodegenerative disease and cancer. We describe a spectroscopic method for the global quantification of 5-hmC in genomic DNA. This method relies on the enzymatic glucosylation of 5-hmC, followed by a glucose oxidation step that results in the formation of aldehyde moieties that are covalently linked to a fluorescent reporter by oxime ligation. The fluorescence intensity of the labeled sample is directly proportional to its 5-hmC content. We show that this simple and cost-effective technique is suitable for quantification of 5-hmC content in different mouse tissues.

Circumstellar Dust in Symbiotic Novae

NASA Astrophysics Data System (ADS)

Jurkic, T.; Kotnik-Karuza, D.

2015-12-01

We present a model of inner dust regions around the cool Mira component of the two symbiotic novae, RR Tel and HM Sge, based on the near-IR photometry, ISO spectra and mid-IR interferometry. The dust properties were determined using the DUSTY code. A compact circumstellar silicate dust shell with inner dust shell temperatures between 900 K and 1300 K and of moderate optical depth can explain all the observations. RR Tel shows the presence of an equatorially enhanced dust density during minimum obscuration. Obscuration events are explained by an increase in optical depth caused by the newly condensed dust. The mass loss rates are significantly higher than in intermediate-period single Miras but in agreement with longer-period O-rich AGB stars.

Spectrophotometric observations of symbiotic stars and related objects

NASA Technical Reports Server (NTRS)

Blair, W. P.; Feibelman, W. A.; Michalitsianos, A. G.; Stencel, R. E.

1983-01-01

Calibrated optical spectrophotometric observations of 16 symbiotic and symbiotic-like objects are presented. The objects observed include Z And, T CrB, CH Cyg, CI Cyg, V1016 Cyg, V1329 Cyg, AG Dra, YY Her, RS Oph, XX Oph, AG Peg, AX Per, CL Sco, HM Sge, AS 289, and M1-2. Integrated emission-line intensities are tabulated for comparison with ultraviolet and infrared data, as well as with previous optical studies. The reddening to each of the objects is derived by assuming that Balmer lines are emitted in their case B recombination ratios. However, the values so derived are often systematically higher than reddening estimates from the ultraviolet 2200 A feature. Comparisons with the available data from other wavelength ranges are noted.

Provenance analysis of heavy minerals in beach sands (Falkland Islands/Islas Malvinas) - A view to mineral deposits and the geodynamics of the South Atlantic Ocean

NASA Astrophysics Data System (ADS)

Dill, Harald G.; Skoda, Radek

2017-10-01

Beach sands are ideal traps to collect heavy minerals (HM) from different geodynamic settings and mineral deposits. The coastal sediments contain a mixture of HM derived from the submarine shelf and from source rocks in the hinterland. This is true in a transgressive periglacial regime, where drowned valleys and estuaries are instrumental in draining HM to the arenaceous beach sediments from more distal basement lithologies. A scenario like this can be found in the Falkland Islands/Islas Malvinas. The site under study is the missing link between South Africa and South America, the splitting-apart of which is mirrored by the HM distribution predominantly concentrated in the backshore and dune belt along the coast. The HM are subdivided into three HM associations reflecting the geodynamic evolution of the South Atlantic Ocean and of some of the prominent mineral deposits on the Gondwana Continent: (1) Gondwana cratons and Proterozoic orogens, with Cr and BIF deposits (rutile, zircon, ilmenite, tourmaline, garnet, Cr spinel), (2) rift-related and break-apart magmatic lithologies with mantle-derived pipe rocks such as kimberlites (zircon, pyroxene, spinel, Mg ilmenite), (3) Cordillera-type lithologies with polymetallic stratabound deposits (tourmaline, amphibole, chlorite, REE phosphates). The variation of the major HM from the stable craton (Kalahari-Kaapvaal Craton) in the East to the mobile fold belt (Andes) in the West follows the order of stability of HM. In addition to these 3 geodynamic HM groups, sporadic occurrences of HM originating from alteration (leucoxene, chlorite s.s.s. (= solid solution series)) are part of armored relics such as "nigrine" which on transport disintegrated and thereby released these HM. The major ultrastable and stable HM zircon, rutile, tourmaline s.s.s., spinel s.s.s., and garnet s.s.s. are displayed in a synoptical x-y plot showing the mantle and crustal trends of fractionation and formation of cumulates by means of particular mineral associations as well as the chemical composition of their s.s.s. Five different geodynamic-lithological patterns, each represented by a set of type-lithologies are established for the cratonic magmatic-metamorphic lithosphere. Based on the HM, the geodynamic setting under study is dominated by source rocks typical of a primitive, cratonic setting.

Assessment of antioxidative ability in brain: Imaging of glutathione localization with technetium-99M meso-hexamethyl propyleneamine oxime

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

Sasaki, T.; Toyama, H.; Oda, K.

1994-05-01

An oxidative stress is postulated to be important in tissue injury after ischemia and reperfusion, inflammation, aging and various disease. Glutathione (GSH), one of the major antioxidants in the brain, is presumed to be responsible for the metabolism and retention of [Tc-99m] HM-PAO. In order to visualize the regional localization of GSH in the brain, the relationship between the concentrations of tissue GSH and uptake of [Tc-99m] meso-HM-PAO and [Tc-99m] d,l-HM-PAO was studied in mice. Increasing load of diethyl maleate (DEM), a reducing agent of GSH and several other thiols, before [Tc-99m] meso-HM-PAO injection, led to a dose dependent decreasemore » of GSH and [Tc-99m] meso-HM-PAO. At the highest dose of loaded DEM, the uptake of [Tc-99m] meso-HM-PAO in the brain was decreased to 20-30% of the control. In contrast, pretreatment with DEM did little affect the [Tc-99m] d,l-HM-PAO uptake. To elucidate the retention mechanism of [Tc-99m] HM-PAO in brain, we studied the in vitro interactions of [Tc-99m] meso-HMPAO and [Tc-99m] d,l-HM-PAO with GSH, ascorbate and cysteine by measuring octanol-extractable radioactivity, which is remaining intact [Tc-99m] HM-PAO, as a function of incubation period. The disappearance raw of [Tc-99m] meso-HMPAO and [TC-99m] d,l-HM-PAO were 0.18 and 0.96%/min, respectively. Either meso or d,l-isomer did not interact with ascorbate or cysteine. This result suggested that the retention mechanism of [Tc-99m] meso- and d,l-isomers in brain was related to their specific interaction with GSH, and did not related to non-specific interaction with various thiols or other reducing agents. This extremely high reaction rate of [Tc-99m] d,l-HM-PAO with GSH could explain the capability of a small amount of GSH to trap [Tc-99m] d,l-HM-PAO in maximum DEM loading. These results indicated that [Tc-99m] meso-HMPAO would be suitable to image the concentration of GSH in the brain, as opposed d,l-isomer that images blood flow.« less

[Control of Soil Nutrient Loss of Typical Reforestation Patterns Along the Three Gorges Reservoir Area].

PubMed

Wu, Dong; Huang, Zhi-lin; Xiao, Wen-fa; Zeng, Li-xiong

2015-10-01

Annual soil nutrient loss characteristics on typical reforestation patterns in watershed along the Three Gorges Reservoir Area were studied based on runoff plot experiment. Runoff and sediment nutrition content from May to October 2014 of typical reforestation patterns including garden plot (tea garden), forest land (Chinese chestnut) and the original slope farmland were determined and then analyzed. The results showed that: (1) After the Returning Farmland to Forest Project the quantity of annual soil nutrient (nitrogen and phosphorus, the sum of them in sediment and runoff) loss decreased. The output of total nitrogen (TN) was in the order of slope farmland (2 444.27 g x hm(-2)) > tea garden (998.70 g x hm(-2)) > Chinese chestnut forest (532.61 g x hm(-2)), and for total phosphorus (TP) loss was slope farmland (1 690.48 g x hm(-2)) > tea garden (488.06 g x hm(-2)) > Chinese chestnut forest (129.00 g x hm(-2)) . Compared with slope farmland, the load of TN and TP output of reforestation patterns decreased 68.68% and 81.75%, respectively. (2) Compared with slope farmland, available nitrogen loss decreased in reforestation patterns. Total nitrate nitrogen (NO3(-)-N) loss ranked in the order of slope farmland (113.79 g x hm(-2)) > tea garden (73.75 g x hm(-2)) > Chinese chestnut forest (56.06 g x hm(-2)) The largest amount of ammonium nitrogen (NH4(+)-N) was found in tea garden (69.34 g x hm(-2)), then in farmland (52.45 g x hm(-2)), and the least in Chinese chestnut forest (47.23 g x hm(-2)). (3) The main route of NO3(-)-N and NH4(+)-N loss was both through runoff, the quantity of NO3(-)-N and NH4(+)-N output in which accounted for 91.4% and 92.2% of the total, respectively. The quantity of TN and TP in sediment accounted for 86.6% and 98.4% of the total. TN and TP loss showed an extremely significant correlation with sediments, which showed that sediment output was the main approach of TN and TP loss.

"Breastfeeding" but not at the breast: Mothers' descriptions of providing pumped human milk to their infants via other containers and caregivers.

PubMed

Felice, Julia P; Geraghty, Sheela R; Quaglieri, Caroline W; Yamada, Rei; Wong, Adriana J; Rasmussen, Kathleen M

2017-07-01

As pumping has become more prevalent among American women, pumped human milk (HM) is on the rise in their infants' diets in place of some or all feeding at the breast. We aimed to fill a gap in knowledge about mothers' motivations, practices and perceptions related to pumping, and about mothers' and other caregivers' motivations, practices, and perceptions related to feeding pumped HM. Results related to providing pumped HM are reported here, and results related to pumping are reported elsewhere. We conducted in-depth, semi-structured interviews among a diverse sample of mothers whose infants were fed pumped HM (n = 20), following each up to 1 year postpartum. Data were analyzed using thematic analysis with Atlas.ti. Nearly all mothers felt bottles were necessary to meet infant HM-feeding goals. Nearly all pumped HM was fed by other caregivers because mothers typically preferred and prioritized feeding at the breast for convenience and maintaining their milk supply. Infants were bottle-fed HM for several reasons that changed over time, such as mother's absence, latch difficulty, or desire to share the burden and bonding of feeding. Feeding practices differed between feeds from bottles versus at the breast; some infants were bottle-fed on schedules but fed at the breast on demand. Mothers' methods for storing, transporting, and preparing HM varied substantially and included practices associated with loss of nutrients and microbial contamination. Mothers' reasons for bottle-feeding HM may affect how much their infants are bottle-fed. Consumption of pumped HM may not provide the same benefits to infants as feeding at the breast. These findings highlight important avenues for future research into the relationships between bottle-feeding HM and infant health, growth, and developmental outcomes. © 2017 John Wiley & Sons Ltd.

Protein Digestion and Quality of Goat and Cow Milk Infant Formula and Human Milk Under Simulated Infant Conditions

PubMed Central

Maathuis, Annet; Havenaar, Robert; He, Tao; Bellmann, Susann

2017-01-01

ABSTRACT Objective: The aim of this study was to determine the kinetics of true ileal protein digestion and digestible indispensable amino acid score (DIAAS) of a goat milk-based infant formula (GIF), a cow milk-based infant formula (CIF), and human milk (HM). Methods: The GIF, CIF, and HM were investigated in an in vitro gastrointestinal model simulating infant conditions. Digested compounds were dialyzed from the intestinal compartment as bioaccessible fraction. Dialysate was collected in 15 to 60-minute periods for 4 hours. True ileal protein digestibility and DIAAS were determined as bioaccessible nitrogen (N) and amino acids. Results: N bioaccessibility from the GIF showed similar kinetics to that of HM. The CIF showed a delay in N bioaccessibility versus the GIF and HM. In the 1st hour of digestion, N bioaccessibility was 19.9% ± 3.5% and 23.3% ± 1.3% for the GIF and HM, respectively, and 11.2% ± 0.6% for CIF (P < 0.05 vs HM). In the 3rd hour of digestion, the N bioaccessibility was higher (P < 0.05) for the CIF (28.9% ± 1.2%) than for the GIF (22.5% ± 1.6%) and HM (20.6% ± 1.0%). After 4 hours, the true ileal protein digestibility of the GIF, CIF, and HM was 78.3% ± 3.7%, 73.4% ± 2.7%, and 77.9% ± 4.1%, respectively. The DIAAS for the GIF, CIF, and HM for 0- to 6-month-old infants was 83%, 75%, and 77% for aromatic AA. Conclusion: The protein quality is not different between the GIF, CIF, and HM, but the kinetics of protein digestion of the GIF is more comparable to that of HM than that of the CIF. PMID:28968291

Protein Digestion and Quality of Goat and Cow Milk Infant Formula and Human Milk Under Simulated Infant Conditions.

PubMed

Maathuis, Annet; Havenaar, Robert; He, Tao; Bellmann, Susann

2017-12-01

The aim of this study was to determine the kinetics of true ileal protein digestion and digestible indispensable amino acid score (DIAAS) of a goat milk-based infant formula (GIF), a cow milk-based infant formula (CIF), and human milk (HM). The GIF, CIF, and HM were investigated in an in vitro gastrointestinal model simulating infant conditions. Digested compounds were dialyzed from the intestinal compartment as bioaccessible fraction. Dialysate was collected in 15 to 60-minute periods for 4 hours. True ileal protein digestibility and DIAAS were determined as bioaccessible nitrogen (N) and amino acids. N bioaccessibility from the GIF showed similar kinetics to that of HM. The CIF showed a delay in N bioaccessibility versus the GIF and HM. In the 1st hour of digestion, N bioaccessibility was 19.9% ± 3.5% and 23.3% ± 1.3% for the GIF and HM, respectively, and 11.2% ± 0.6% for CIF (P < 0.05 vs HM). In the 3rd hour of digestion, the N bioaccessibility was higher (P < 0.05) for the CIF (28.9% ± 1.2%) than for the GIF (22.5% ± 1.6%) and HM (20.6% ± 1.0%). After 4 hours, the true ileal protein digestibility of the GIF, CIF, and HM was 78.3% ± 3.7%, 73.4% ± 2.7%, and 77.9% ± 4.1%, respectively. The DIAAS for the GIF, CIF, and HM for 0- to 6-month-old infants was 83%, 75%, and 77% for aromatic AA. The protein quality is not different between the GIF, CIF, and HM, but the kinetics of protein digestion of the GIF is more comparable to that of HM than that of the CIF.

Superiority of automatic remote monitoring compared with in-person evaluation for scheduled ICD follow-up in the TRUST trial - testing execution of the recommendations.

PubMed

Varma, Niraj; Michalski, Justin; Stambler, Bruce; Pavri, Behzad B

2014-05-21

To test recommended implantable cardioverter defibrillator (ICD) follow-up methods by 'in-person evaluations' (IPE) vs. 'remote Home Monitoring' (HM). ICD patients were randomized 2:1 to automatic HM or to Conventional monitoring, with follow-up checks scheduled at 3, 6, 9, 12, and 15 months post-implant. Conventional patients were evaluated with IPE only. Home Monitoring patients were assessed remotely only for 1 year between 3 and 15 month evaluations. Adherence to follow-up was measured. HM and Conventional patients were similar (age 63 years, 72% male, left ventricular ejection fraction 29%, primary prevention 73%, DDD 57%). Conventional management suffered greater patient attrition during the trial (20.1 vs. 14.2% in HM, P = 0.007). Three month follow-up occurred in 84% in both groups. There was 100% adherence (5 of 5 checks) in 47.3% Conventional vs. 59.7% HM (P < 0.001). Between 3 and 15 months, HM exhibited superior (2.2×) adherence to scheduled follow-up [incidence of failed follow up was 146 of 2421 (6.0%) in HM vs. 145 of 1098 (13.2%) in Conventional, P < 0.001] and punctuality. In HM (daily transmission success rate median 91%), transmission loss caused only 22 of 2275 (0.97%) failed HM evaluations between 3 and 15 months; others resulted from clinic oversight. Overall IPE failure rate in Conventional [193 of 1841 (10.5%) exceeded that in HM [97 of 1484 (6.5%), P < 0.001] by 62%, i.e. HM patients remained more loyal to IPE when this was mandated. Automatic remote monitoring better preserves patient retention and adherence to scheduled follow-up compared with IPE. NCT00336284. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Cardiology.

Improved LIBS limit of detection of Be, Mg, Si, Mn, Fe and Cu in aluminum alloy samples using a portable Echelle spectrometer with ICCD camera

NASA Astrophysics Data System (ADS)

Mohamed, Walid Tawfik Y.

2008-02-01

Laser-induced breakdown spectroscopy (LIBS) is a laser-based technique that can provide non-intrusive, qualitative and quantitative measurement of metals in various environments. LIBS uses the plasma generated by a high-energy laser beam to prepare and excite the sample in one step. In the present work, LIBS has been applied to perform elemental analysis of six trace elements simultaneously in aluminum alloy targets. The plasma is generated by focusing a pulsed Nd:YAG laser on the target in air at atmospheric pressure. LIBS limit of detection (LOD) is affected by many experimental parameters such as interferences, self-absorption, spectral overlap and matrix effect. We aimed to improve the LIBS LOD by optimizing these experimental parameters as possible. In doing so, a portable Echelle spectrometer with intensified CCD camera was used to detect the LIBS plasma emission. This advanced Echelle spectrometer provides a constant spectral resolution (CSR) of 7500 corresponding to 4 pixels FWHM over a wavelength range 200-1000 nm displayable in a single spectrum. Then, the calibration curves for iron, beryllium, magnesium, silicon, manganese and copper as minor elements were achieved with linear regression coefficients between 98-99% on average in aluminum standard sample alloys. New LOD values were achieved in the ppm range with high precision (RSD 3-8%). From the application view point, improving LIBS LOD is very important in the on-line industrial process control to follow-up multi-elements for the correct alloying in metals.

Holocene closure of Lib Pond, Marshall Islands.

PubMed

Myhrvold, Conor L; Janny, Fran; Nelson, Daniel; Ladd, S Nemiah; Atwood, Alyssa; Sachs, Julian P

2014-01-01

Well-preserved sediment from closed water bodies of atolls such as Lib Pond are rare opportunities to reconstruct the past regional climate, which pieced together across a latitude and longitude range identify the range of movement patterns of wider scale climate phenomena such as the Intertropical Convergence Zone (ITCZ) and El Niño Southern Oscillation (ENSO). We conducted the first physico-chemical survey of Lib Pond, a shallow, closed-water saline lake located on remote and difficult to access Lib Island in the Marshall Islands at 8° 18' 48.99″ N, 167 22' 51.90″ E in the Pacific Ocean, in July 2009. We performed a bathymetric survey, recorded salinity, dissolved oxygen, pH, and temperature profiles, monitored the tidal variability, and conducted a vegetation survey surrounding the lake. From bathymetric data we calculated the lake volume, which we used to estimate the lake's salt budget, and ultimately the residence time of water in the lake basin. We took a series of sediment cores from the lake, cores which indicate Lib Island's changing environment and climate. Radiocarbon measurements determined sediment age, and reveal significant mixing over the last 2 ka of deposition. We conclude that prior to 3 ka, Lib Island was an atoll with a central lagoon connected to the open ocean, which was then closed off from the open ocean to form the brackish system that exists today. We predict that the sediment accumulation in Lib Pond evident today will continue. As seawater is inhibited from exchanging with fresh water, Lib Pond will become a shallower lake with increasingly fresh water.

Holocene Closure of Lib Pond, Marshall Islands

PubMed Central

Myhrvold, Conor L.; Janny, Fran; Nelson, Daniel; Ladd, S. Nemiah; Atwood, Alyssa; Sachs, Julian P.

2014-01-01

Well-preserved sediment from closed water bodies of atolls such as Lib Pond are rare opportunities to reconstruct the past regional climate, which pieced together across a latitude and longitude range identify the range of movement patterns of wider scale climate phenomena such as the Intertropical Convergence Zone (ITCZ) and El Niño Southern Oscillation (ENSO). We conducted the first physico-chemical survey of Lib Pond, a shallow, closed-water saline lake located on remote and difficult to access Lib Island in the Marshall Islands at 8° 18′ 48.99″ N, 167 22′ 51.90″ E in the Pacific Ocean, in July 2009. We performed a bathymetric survey, recorded salinity, dissolved oxygen, pH, and temperature profiles, monitored the tidal variability, and conducted a vegetation survey surrounding the lake. From bathymetric data we calculated the lake volume, which we used to estimate the lake's salt budget, and ultimately the residence time of water in the lake basin. We took a series of sediment cores from the lake, cores which indicate Lib Island's changing environment and climate. Radiocarbon measurements determined sediment age, and reveal significant mixing over the last 2 ka of deposition. We conclude that prior to 3 ka, Lib Island was an atoll with a central lagoon connected to the open ocean, which was then closed off from the open ocean to form the brackish system that exists today. We predict that the sediment accumulation in Lib Pond evident today will continue. As seawater is inhibited from exchanging with fresh water, Lib Pond will become a shallower lake with increasingly fresh water. PMID:24638020

The effect of bacterial environmental and metabolic stresses on a laser-induced breakdown spectroscopy (LIBS) based identification of Escherichia coli and Streptococcus viridans.

PubMed

Mohaidat, Qassem; Palchaudhuri, Sunil; Rehse, Steven J

2011-04-01

In this paper we investigate the effect that adverse environmental and metabolic stresses have on the laser-induced breakdown spectroscopy (LIBS) identification of bacterial specimens. Single-pulse LIBS spectra were acquired from a non-pathogenic strain of Escherichia coli cultured in two different nutrient media: a trypticase soy agar and a MacConkey agar with a 0.01% concentration of deoxycholate. A chemometric discriminant function analysis showed that the LIBS spectra acquired from bacteria grown in these two media were indistinguishable and easily discriminated from spectra acquired from two other non-pathogenic E. coli strains. LIBS spectra were obtained from specimens of a nonpathogenic E. coli strain and an avirulent derivative of the pathogen Streptococcus viridans in three different metabolic situations: live bacteria reproducing in the log-phase, bacteria inactivated on an abiotic surface by exposure to bactericidal ultraviolet irradiation, and bacteria killed via autoclaving. All bacteria were correctly identified regardless of their metabolic state. This successful identification suggests the possibility of testing specimens that have been rendered safe for handling prior to LIBS identification. This would greatly enhance personnel safety and lower the cost of a LIBS-based diagnostic test. LIBS spectra were obtained from pathogenic and non-pathogenic bacteria that were deprived of nutrition for a period of time ranging from one day to nine days by deposition on an abiotic surface at room temperature. All specimens were successfully classified by species regardless of the duration of nutrient deprivation. © 2011 Society for Applied Spectroscopy

Wavelength dependence of laser induced breakdown spectroscopy (LIBS) on questioned document investigation.

PubMed

Elsherbiny, Nany; Aied Nassef, O

2015-07-01

The fast and nearly non-destructive criteria of laser induced breakdown spectroscopy (LIBS) technique has been exploited for forensic purposes, specifically, document investigation. The dependence of the optical emission spectra of different black gel ink samples on the excitation laser wavelength, namely the visible wavelength at λ=532 nm and the IR wavelength at λ=1064 nm, was studied. The inks of thirty black gel-ink pens comprising ten brands were analyzed to determine the variation of the chemical composition of ink and to discriminate among them with minimum mass removal and minimum damage to the document's paper. Under the adopted experimental conditions, the ability of the visible LIBS to differentiate among the different ink samples was successful compared to IR LIBS at the same laser pulse energy (~25 mJ/pulse, laser fluence is ~1400J·cm(-2) for visible laser and ~1100J·cm(-2) for IR laser) which could be attributed to the IR absorption effects by the black ink. However, the visible LIBS produces deeper crater with respect to that produced by IR LIBS. Applying IR LIBS with higher pulse energy of ~87mJ (laser fluence is ~4100J·cm(-2)), identification and differentiation of the adopted samples was performed with producing a larger-diameter but superficial crater. The plasma parameters are discussed at the adopted experimental conditions. The results support the potential of LIBS technique using both the visible and IR lasers to be commercially developed for forensic document examination. Copyright © 2015 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

Genome-wide loss of 5-hmC is a novel epigenetic feature of Huntington's disease.

PubMed

Wang, Fengli; Yang, Yeran; Lin, Xiwen; Wang, Jiu-Qiang; Wu, Yong-Sheng; Xie, Wenjuan; Wang, Dandan; Zhu, Shu; Liao, You-Qi; Sun, Qinmiao; Yang, Yun-Gui; Luo, Huai-Rong; Guo, Caixia; Han, Chunsheng; Tang, Tie-Shan

2013-09-15

5-Hydroxymethylcytosine (5-hmC) may represent a new epigenetic modification of cytosine. While the dynamics of 5-hmC during neurodevelopment have recently been reported, little is known about its genomic distribution and function(s) in neurodegenerative diseases such as Huntington's disease (HD). We here observed a marked reduction of the 5-hmC signal in YAC128 (yeast artificial chromosome transgene with 128 CAG repeats) HD mouse brain tissues when compared with age-matched wild-type (WT) mice, suggesting a deficiency of 5-hmC reconstruction in HD brains during postnatal development. Genome-wide distribution analysis of 5-hmC further confirmed the diminishment of the 5-hmC signal in striatum and cortex in YAC128 HD mice. General genomic features of 5-hmC are highly conserved, not being affected by either disease or brain regions. Intriguingly, we have identified disease-specific (YAC128 versus WT) differentially hydroxymethylated regions (DhMRs), and found that acquisition of DhmRs in gene body is a positive epigenetic regulator for gene expression. Ingenuity pathway analysis (IPA) of genotype-specific DhMR-annotated genes revealed that alternation of a number of canonical pathways involving neuronal development/differentiation (Wnt/β-catenin/Sox pathway, axonal guidance signaling pathway) and neuronal function/survival (glutamate receptor/calcium/CREB, GABA receptor signaling, dopamine-DARPP32 feedback pathway, etc.) could be important for the onset of HD. Our results indicate that loss of the 5-hmC marker is a novel epigenetic feature in HD, and that this aberrant epigenetic regulation may impair the neurogenesis, neuronal function and survival in HD brain. Our study also opens a new avenue for HD treatment; re-establishing the native 5-hmC landscape may have the potential to slow/halt the progression of HD.

[Crop-soil nitrogen cycling and soil organic carbon balance in black soil zone of Jilin Province based on DSSAT model].

PubMed

Yang, Jing-min; Dou, Sen; Yang, Jing-yi; Hoogenboom, Gerrit; Jiang, Xu; Zhang, Zhong-qing; Jiang, Hong-wei; Jia, Li-hui

2011-08-01

By using the CERES-Maize crop model and Century soil model in Decision Support System of Agrotechnology Transfer (DSSAT) model, this paper studied the effects of crop management parameters, fertilizer N application rate, soil initial N supply, and crop residue application on the maize growth, crop-soil N cycling, and soil organic C and N ecological balance in black soil (Mollisol) zone of Jilin Province, Northeast China. Taking 12,000-15,000 kg x hm(-2) as the target yield of maize, the optimum N application rate was 200-240 kg N x hm(-2). Under this fertilization, the aboveground part N uptake was 250-290 kg N x hm(-2), among which, 120-140 kg N x hm(-2) came from soil, and 130-150 kg N x hm(-2) came from fertilizer. Increasing the N application rate (250-420 kg N x hm(-2)) induced an obvious increase of soil residual N (63-183 kg x hm(-2)); delaying the N topdressing date also induced the increase of the residual N. When the crop residue application exceeded 6000 kg x hm(-2), the soil active organic C and N could maintain the supply/demand balance during maize growth season. To achieve the target maize yield and maintain the ecological balance of soil organic C and N in black soil zone of Jilin Province, the chemical N application rate would be controlled in the range of 200-240 kg N x hm(-2), topdressing N should be at proper date, and the application amount of crop residue would be up to 6000 kg x hm(-2).

Computer keyboard covers impregnated with a novel antimicrobial polymer significantly reduce microbial contamination.

PubMed

D'Antonio, Natalie N; Rihs, John D; Stout, Janet E; Yu, Victor L

2013-04-01

Contaminated computer keyboards have been acknowledged as a potential source for bacterial transmission between health care providers and patients. Biosafe HM 4100 is an antimicrobial polymer that can be incorporated into the polyurethane material used to make keyboard covers. This study aimed to determine whether plastic keyboard covers containing HM 4100 effectively minimize the survival of bacterial species commonly present on health care environmental surfaces. Polyurethane material that contained 0.5% HM 4100, 1% HM 4100, and 1% HM 4100 with spray coating of 1% HM 4100 were tested. In 2 separate experiments, the surfaces of test materials were inoculated with suspensions of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecalis (VREF), Escherichia coli, or Pseudomonas aeruginosa. Viability was assessed on the materials at 0, 10, 30, 60, 120, and 240 minutes after inoculation. Maximum reductions in viability were observed for all 4 organisms at the longest tested time period on each test material. Mean reductions on the 0.5% HM 4100 material at 240 minutes were 99.99% for E coli, 97.8% for MRSA, 95.0% for VREF, and 92.1% for P aeruginosa. Mean reductions on the 1% HM 4100 at 120 minutes were 99.9% for VREF, 99.9% for MRSA, 99.9% for P aeruginosa, and 99.5% for E coli. Mean reductions on the 1% HM 4100 plus spray coating at 30 minutes were 99.9% for E coli, 99.8% for VREF, 98.8% for P aeruginosa, and 97.2% for MRSA. Incorporation of the HM 4100 antimicrobial polymer into polyurethane keyboard material may reduce the hand carriage of bacteria between health care providers and patients. Copyright © 2013 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Rate of progression of total, upper, and lower visual field defects in patients with open-angle glaucoma and high myopia.

PubMed

Yoshino, Takaiko; Fukuchi, Takeo; Togano, Tetsuya; Sakaue, Yuta; Seki, Masaaki; Tanaka, Takayuki; Ueda, Jun

2016-03-01

We evaluated the rate of progression of total, upper, and lower visual field defects in patients with treated primary open-angle glaucoma (POAG) with high myopia (HM). Seventy eyes of 70 POAG patients with HM [≤-8 diopters (D)] were examined. The mean deviation (MD) slope and the upper and lower total deviation (upper TD, lower TD) slopes of the Humphrey Field Analyzer were calculated in patients with high-tension glaucoma (HTG) (>21 mmHg) versus normal-tension glaucoma (NTG) (≤21 mmHg). The mean age of all the patients (29 eyes with HTG and 41 eyes with NTG) was 48.5 ± 9.6 years. The MD slope, and upper and lower TD slopes of the HM group were compared to those of the non-HM group (NHM) (>-8 D) selected from 544 eyes in 325 age-matched POAG patients. In all, 70 eyes with HM and NHM were examined. The mean MD slope was -0.33 ± 0.33 dB/year in the HM, and -0.38 ± 0.49 dB/year in the NHM. There were no statistical differences between the HM and NHM (p = 0.9565). In the comparison of HTG versus NTG patients in both groups, the MD slope, and upper and lower TD slopes were similar. The rate of progression of total, upper, and lower visual field defects was similar among patients with HM and NHM. Although HM is a risk factor for the onset of glaucoma, HM may not be a risk factor for progression of visual field defects as assessed by the progression rate under treatment.

Leveraging the Libguides Platform for Electronic Resources Access Assistance

ERIC Educational Resources Information Center

Erb, Rachel A.; Erb, Brian

2014-01-01

This case study offers an alternative use of LibGuides beyond its intended purpose to offer course and subject guides. LibGuides have become an integral part of the virtual instruction landscape at Colorado State University (CSU) Libraries. We discovered that the LibGuides platform can also be effectively harnessed to provide support for…

Implementing LibGuides 2: An Academic Case Study

ERIC Educational Resources Information Center

Duncan, Vicky; Lucky, Shannon; McLean, Jaclyn

2015-01-01

Since 1997, the University of Saskatchewan Library has used "subject pages" to highlight key library resources. When Springshare announced it was launching LibGuides v2, a project team was assembled to transition a mixture of locally produced guides and guides created with the original LibGuides v1 software. This article synthesizes best…

Accuracy Enhancement of Raman Spectroscopy Using Complementary Laser-Induced Breakdown Spectroscopy (LIBS) with Geologically Mixed Samples.

PubMed

Choi, Soojin; Kim, Dongyoung; Yang, Junho; Yoh, Jack J

2017-04-01

Quantitative Raman analysis was carried out with geologically mixed samples that have various matrices. In order to compensate the matrix effect in Raman shift, laser-induced breakdown spectroscopy (LIBS) analysis was performed. Raman spectroscopy revealed the geological materials contained in the mixed samples. However, the analysis of a mixture containing different matrices was inaccurate due to the weak signal of the Raman shift, interference, and the strong matrix effect. On the other hand, the LIBS quantitative analysis of atomic carbon and calcium in mixed samples showed high accuracy. In the case of the calcite and gypsum mixture, the coefficient of determination of atomic carbon using LIBS was 0.99, while the signal using Raman was less than 0.9. Therefore, the geological composition of the mixed samples is first obtained using Raman and the LIBS-based quantitative analysis is then applied to the Raman outcome in order to construct highly accurate univariate calibration curves. The study also focuses on a method to overcome matrix effects through the two complementary spectroscopic techniques of Raman spectroscopy and LIBS.

A review of the development of portable laser induced breakdown spectroscopy and its applications

NASA Astrophysics Data System (ADS)

Rakovský, J.; Čermák, P.; Musset, O.; Veis, P.

2014-11-01

In this review, we present person-transportable laser induced breakdown spectroscopy (LIBS) devices that have previously been developed and reported in the literature as well as their applications. They are compared with X-ray fluorescent (XRF) devices, which represent their strongest competition. Although LIBS devices have advantages over XRF devices, such as sensitivity to the light elements, high spatial resolution and the possibility to distinguish between different layers of the sample, there are also disadvantages and both are discussed here. Furthermore, the essential portable LIBS instrumentation (laser, spectrograph and detector) is presented, and published results related to new laser sources (diode-pumped solid-state, microchip and fiber lasers) used in LIBS are overviewed. Compared to conventional compact flashlamp pumped solid-state lasers, the new laser sources provide higher repetition rates, higher efficiency (less power consumption) and higher beam quality, resulting in higher fluences, even for lower energies, and could potentially increase the figure of merit of portable LIBS instruments. Compact spectrometers used in portable LIBS devices and their parts (spectrograph, detector) are also discussed.

Evaluation of Optical Depths and Self-Absorption of Strontium and Aluminum Emission Lines in Laser-Induced Breakdown Spectroscopy (LIBS).

PubMed

Alfarraj, Bader A; Bhatt, Chet R; Yueh, Fang Yu; Singh, Jagdish P

2017-04-01

Laser-induced breakdown spectroscopy (LIBS) is a widely used laser spectroscopic technique in various fields, such as material science, forensic science, biological science, and the chemical and pharmaceutical industries. In most LIBS work, the analysis is performed using radiative transitions from atomic emissions. In this study, the plasma temperature and the product [Formula: see text] (the number density N and the absorption path length [Formula: see text]) were determined to evaluate the optical depths and the self-absorption of Sr and Al lines. A binary mixture of strontium nitrate and aluminum oxide was used as a sample, consisting of variety of different concentrations in powder form. Laser-induced breakdown spectroscopy spectra were collected by varying various parameters, such as laser energy, gate delay time, and gate width time to optimize the LIBS signals. Atomic emission from Sr and Al lines, as observed in the LIBS spectra of different sample compositions, was used to characterize the laser induced plasma and evaluate the optical depths and self-absorption of LIBS.

Anomaly Monitoring Method for Key Components of Satellite

PubMed Central

Fan, Linjun; Xiao, Weidong; Tang, Jun

2014-01-01

This paper presented a fault diagnosis method for key components of satellite, called Anomaly Monitoring Method (AMM), which is made up of state estimation based on Multivariate State Estimation Techniques (MSET) and anomaly detection based on Sequential Probability Ratio Test (SPRT). On the basis of analysis failure of lithium-ion batteries (LIBs), we divided the failure of LIBs into internal failure, external failure, and thermal runaway and selected electrolyte resistance (R e) and the charge transfer resistance (R ct) as the key parameters of state estimation. Then, through the actual in-orbit telemetry data of the key parameters of LIBs, we obtained the actual residual value (R X) and healthy residual value (R L) of LIBs based on the state estimation of MSET, and then, through the residual values (R X and R L) of LIBs, we detected the anomaly states based on the anomaly detection of SPRT. Lastly, we conducted an example of AMM for LIBs, and, according to the results of AMM, we validated the feasibility and effectiveness of AMM by comparing it with the results of threshold detective method (TDM). PMID:24587703

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

Zhang, Chao; Xu, Jun; Cao, Lei

The electrodes of lithium-ion batteries (LIB) are known to be brittle and to fail earlier than the separators during an external crush event. Thus, the understanding of mechanical failure mechanism for LIB electrodes (anode and cathode) is critical for the safety design of LIB cells. In this paper, we present experimental and numerical studies on the constitutive behavior and progression of failure in LIB electrodes. Mechanical tests were designed and conducted to evaluate the constitutive properties of porous electrodes. Constitutive models were developed to describe the stress-strain response of electrodes under uniaxial tensile and compressive loads. The failure criterion andmore » a damage model were introduced to model their unique tensile and compressive failure behavior. The failure mechanism of LIB electrodes was studied using the blunt rod test on dry electrodes, and numerical models were built to simulate progressive failure. The different failure processes were examined and analyzed in detail numerically, and correlated with experimentally observed failure phenomena. Finally, the test results and models improve our understanding of failure behavior in LIB electrodes, and provide constructive insights on future development of physics-based safety design tools for battery structures under mechanical abuse.« less

Prospects for laser-induced breakdown spectroscopy for biomedical applications: a review.

PubMed

Singh, Vivek Kumar; Rai, Awadhesh Kumar

2011-09-01

We review the different spectroscopic techniques including the most recent laser-induced breakdown spectroscopy (LIBS) for the characterization of materials in any phase (solid, liquid or gas) including biological materials. A brief history of the laser and its application in bioscience is presented. The development of LIBS, its working principle and its instrumentation (different parts of the experimental set up) are briefly summarized. The generation of laser-induced plasma and detection of light emitted from this plasma are also discussed. The merit and demerits of LIBS are discussed in comparison with other conventional analytical techniques. The work done using the laser in the biomedical field is also summarized. The analysis of different tissues, mineral analysis in different organs of the human body, characterization of different types of stone formed in the human body, analysis of biological aerosols using the LIBS technique are also summarized. The unique abilities of LIBS including detection of molecular species and calibration-free LIBS are compared with those of other conventional techniques including atomic absorption spectroscopy, inductively coupled plasma atomic emission spectroscopy and mass spectroscopy, and X-ray fluorescence.

Barriers to Human Milk Feeding at Discharge of Very Low–Birthweight Infants: Evaluation of Neighborhood Structural Factors

PubMed Central

Riley, Brittany; Schoeny, Michael; Rogers, Laura; Asiodu, Ifeyinwa V.; Bigger, Harold R.; Meier, Paula P.

2016-01-01

Abstract Background: Although 98% of mothers in our cohort initiated human milk (HM) provision for their very low–birthweight (VLBW) infants, fewer black infants received HM at neonatal intensive care unit (NICU) discharge than non-black infants. This study examined neighborhood structural factors associated with HM feeding at discharge to identify potential barriers. Materials and Methods: Sociodemographic and HM data were prospectively collected for 410 VLBW infants and mothers. Geocoded addresses were linked to neighborhood structural factors. Bivariate and multivariate logistic regression analyses were conducted for the entire cohort and racial/ethnic subgroups. Results: HM feeding at discharge was positively correlated with further distance from Women, Infants, and Children (WIC) office, less violent crime, less poverty, greater maternal education, older maternal age, greater infant gestational age, and shorter NICU hospitalization. Multivariate analysis demonstrated that only maternal race/ethnicity, WIC eligibility, and length of NICU hospitalization predicted HM feeding at discharge for the entire cohort. The interaction between access to a car and race/ethnicity significantly differed between black and white/Asian mothers, although the predicted probability of HM feeding at discharge was not significantly affected by access to a car for any racial/ethnic subgroup. Conclusions: Neighborhood structural factors did not significantly impact HM feeding at discharge. However, lack of access to a car may be a factor for black mothers, potentially representing restricted HM delivery to the NICU or limited social support, and warrants further study. PMID:27347851

Phytoaccumulation of heavy metals in natural plants thriving on wastewater effluent at Hattar industrial estate, Pakistan.

PubMed

Irshad, Muhammad; Ahmad, Sajjad; Pervez, Arshid; Inoue, Mitsuhiro

2015-01-01

The objective of this research was to compare the potential of native plants for the phytoaccumulation of heavy metals (HM). Thirteen predominant plant species (including trees, bushes and grasses) namely Ricinus communis, Ipomoea carnea, Cannabis sativa, Parthenium hysterophorus, Acacia nilotica, Dalbergia sissoo, Acacia modesta, Solanum nigrum, Xanthium stromarium, Chenopodium album, Cynodon dactylon, Eleusine indica, and Dactyloctenium aegyptium were collected from the wastewater originated from Hattar industrial estate of Pakistan, Plants shoots and roots were analyzed for heavy metals/metalloid: Pb, Cr, Cd, Zn, Fe, Ni, and As. Among plant species, the accumulation potential for HM varied depending on the type of element. Regardless of the plant species, HM concentrations varied in the order of Fe>Zn>Cr>Pb>Ni>Cd>As. Tree species of R. communis, A. nilotica, A. modesta, and D. sissoo exhibited an enhanced concentrations of metals. Accumulation pattern of Fe, Pb, Cd, and As in plants could be related to the HM composition of soil and wastewater. Most of the species exhibited higher HM composition in the root as compared to shoot. The species that found with greater ability to absorb HM in the root, got higher HM concentrations in its shoot. Shoot tissue concentrations of HM were attained by the species as D. sissoo>A. modesta>A. nilotica>R. communis>I. carnea>C. album>E. indica>P. hysterophorus>S. nigrum>C. sativa>D. aegyptium>X. strumarium>C. dactylon. Based on results, tree plants were noticed as higher accumulators of HM in polluted soils.

Materials for lithium-ion battery safety.

PubMed

Liu, Kai; Liu, Yayuan; Lin, Dingchang; Pei, Allen; Cui, Yi

2018-06-01

Lithium-ion batteries (LIBs) are considered to be one of the most important energy storage technologies. As the energy density of batteries increases, battery safety becomes even more critical if the energy is released unintentionally. Accidents related to fires and explosions of LIBs occur frequently worldwide. Some have caused serious threats to human life and health and have led to numerous product recalls by manufacturers. These incidents are reminders that safety is a prerequisite for batteries, and serious issues need to be resolved before the future application of high-energy battery systems. This Review aims to summarize the fundamentals of the origins of LIB safety issues and highlight recent key progress in materials design to improve LIB safety. We anticipate that this Review will inspire further improvement in battery safety, especially for emerging LIBs with high-energy density.

Materials for lithium-ion battery safety

PubMed Central

Liu, Kai

2018-01-01

Lithium-ion batteries (LIBs) are considered to be one of the most important energy storage technologies. As the energy density of batteries increases, battery safety becomes even more critical if the energy is released unintentionally. Accidents related to fires and explosions of LIBs occur frequently worldwide. Some have caused serious threats to human life and health and have led to numerous product recalls by manufacturers. These incidents are reminders that safety is a prerequisite for batteries, and serious issues need to be resolved before the future application of high-energy battery systems. This Review aims to summarize the fundamentals of the origins of LIB safety issues and highlight recent key progress in materials design to improve LIB safety. We anticipate that this Review will inspire further improvement in battery safety, especially for emerging LIBs with high-energy density. PMID:29942858

Laser-induced breakdown spectroscopy (LIBS): An innovative tool for studying bacteria

NASA Astrophysics Data System (ADS)

Mohaidat, Qassem I.

Laser-induced breakdown spectroscopy (LIBS) has gained a reputation as a flexible and convenient technique for rapidly determining the elemental composition of samples with minimal or no sample preparation. In this dissertation, I will describe the benefits of using LIBS for the rapid discrimination and identification of bacteria (both pathogenic and non-pathogenic) based on the relative concentration of trace inorganic elements such as Mg, P, Ca, and Na. The speed, portability, and robustness of the technique suggest that LIBS may be applicable as a rapid point-of-care medical diagnostic technology. LIBS spectra of multiple genera of bacteria such as Escherichia, Streptococcus, Mycobacterium, and Staphylococcus were acquired and successfully analyzed using a computerized discriminant function analysis (DFA). It was shown that a LIBS-based bacterial identification might be insensitive to a wide range of biological changes that could occur in the bacterial cell due to a variety of environmental stresses that the cell may encounter. The effect of reducing the number of bacterial cells on the LIBS-based classification was also studied. These results showed that with 2500 bacteria, the identification of bacterial specimens was still possible. Importantly, it was shown that bacteria in mixed samples (more than one type of bacteria being present) were identifiable. The dominant or majority component of a two-component mixture was reliably identified as long as it comprised 70% of the mixture or more. Finally, to simulate a clinical specimen in a precursor to actual clinical tests, Staphylococcus epidermidis bacteria were collected from urine samples (to simulate a urinary tract infection specimen) and were tested via LIBS without washing. The analysis showed that these bacteria possessed exactly the same spectral fingerprint as control bacteria obtained from sterile deionized water, resulting in a 100% correct classification. This indicates that the presence of other trace background biochemicals from clinical fluids will not adversely disrupt a LIBS-based identification of bacteria.

Characterization of laser induced breakdown plasmas used for measurements of arsenic, antimony and selenium hydrides

NASA Astrophysics Data System (ADS)

Simeonsson, J. B.; Williamson, L. J.

2011-09-01

Studies have been performed to characterize laser induced breakdown spectroscopy (LIBS) plasmas formed in Ar/H 2 gas mixtures that are used for hydride generation (HG) LIBS measurements of arsenic (As), antimony (Sb) and selenium (Se) hydrides. The plasma electron density and plasma excitation temperature have been determined through hydrogen, argon and arsenic emission measurements. The electron density ranges from 4.5 × 10 17 to 8.3 × 10 15 cm -3 over time delays of 0.2 to 15 μs. The plasma temperatures range from 8800 to 7700 K for Ar and from 8800 to 6500 K for As in the HG LIBS plasmas. Evaluation of the plasma properties leads to the conclusion that partial local thermodynamic equilibrium conditions are present in the HG LIBS plasmas. Comparison measurements in LIBS plasmas formed in Ar gas only indicate that the temperatures are similar in both plasmas. However it is also observed that the electron density is higher in the Ar only plasmas and that the emission intensities of Ar are higher and decay more slowly in the Ar only plasmas. These differences are attributed to the presence of H 2 which has a higher thermal conductivity and provides additional dissociation, excitation and ionization processes in the HG LIBS plasma environment. Based on the observed results, it is anticipated that changes to the HG conditions that change the amount of H 2 in the plasma will have a significant effect on analyte emission in the HG LIBS plasmas that is independent of changes in the HG efficiency. The HG LIBS plasmas have been evaluated for measurements of elements hydrides using a constant set of HG LIBS plasma conditions. Linear responses are observed and limits of detection of 0.7, 0.2 and 0.6 mg/L are reported for As, Sb and Se, respectively.

Effect of pre-grazing herbage mass on dairy cow performance, grass dry matter production and output from perennial ryegrass (Lolium perenne L.) pastures.

PubMed

Wims, C M; Delaby, L; Boland, T M; O'Donovan, M

2014-01-01

A grazing study was undertaken to examine the effect of maintaining three levels of pre-grazing herbage mass (HM) on dairy cow performance, grass dry matter (DM) production and output from perennial ryegrass (Lolium perenne L.) pastures. Cows were randomly assigned to one of three pre-grazing HM treatments: 1150 - Low HM (L), 1400 - Medium HM (M) or 2000 kg DM/ha - High HM (H). Herbage accumulation under grazing was lowest (P<0.01) on the L treatment and cows grazing the L pastures required more grass silage supplementation during the grazing season (+73 kg DM/cow) to overcome pasture deficits due to lower pasture growth rates (P<0.05). Treatment did not affect daily milk production or pasture intake, although cows grazing the L pastures had to graze a greater daily area (P<0.01) and increase grazing time (P<0.05) to compensate for a lower pre-grazing HM (P<0.01). The results indicate that, while pre-grazing HM did not influence daily milk yield per cow, adapting the practise of grazing low HM (1150 kg DM/ha) pasture reduces pasture DM production and at a system level may increase the requirement for imported feed.

[Regional differences of inputs of organic matter and chemical fertilizer in South Central China].

PubMed

Liu, Huan-yao; Wu, Jin-shui; Zhou, Jiao-gen; Xiao, He-ai; Zhou, Ping

2015-09-01

This article analyzed the inputs of organic matter and chemical fertilizer in the cropland of South Central China, i.e., Hunan, Hubei, Guangdong and Guangxi, and then calculated the budgets of nitrogen (N), phosphorus (P) and potassium (K), based on the data from field investigations and peasant household surveys in the four provinces. The results showed that total amounts of organic matter inputs in the four provinces was ranked as follow: 8993 kg · hm(-2) in Guangxi, 6390 kg · hm(-2) in Hunan, 5012 kg · hm(-2) in Hubei, 4630 kg · hm(-2) in Guangdong, and average NPK inputs in the four provinces were ranked as follow: 777.5 kg · hm(-2) in Guangxi, 501.6 kg · hm(-2) in Hunan, 486.4 kg · hm(-2) in Hubei, 340.4 kg · hm(-2) in Guangdong. The N and P input surpluses were greatest in Guangxi (67.2% and 99.0% as for N and P, respectively) , followed by Hunan (33.2% and 50.8%), Hubei (11.8% and 11.0%), and Guangdong (7.8% and 30.0%). However, K input was deficient in Hunan, Hubei, and Guangdong (6.6%, 18.7% and 12.4%), but surplus in Guangxi (19.5%).

[Effects of nitrogen application levels on yield and active composition content of Desmodium styracifolium].

PubMed

Zhou, Jiamin; Yin, Xiaohong; Chen, Chaojun; Huang, Min; Peng, Fuyuan; Zhu, Xiaoqi

2010-06-01

To find out the optimal nitrogen application level of Desmodium styracifolium. A field experiment using randomized block design was carried out to study the effects of 5 nitrogen application levels (150, 187.5, 225.0, 262.5 and 300.0 kg x hm(-2)) on yield and active component content of D. styracifolium. Nitrogen application could increase the yield and contents of polysaccharide, total flavonoides and total saponins of D. styracifolium. However, the enhancing extent of the active component content and the yield were not always significant with the increase of nitrogen level. In which, the yield were not significantly different among the nitrogen application levels of 225.0, 262.5, 300.0 kg x hm(-2) the polysaccharide content was no significantly difference among the nitrogen application levels of 225.0, 262. 5 and 300.0 kg x hm(-2), the total flavonoides content under the nitrogen level of 300.0 kg x hm(-2) was significantly lower than that of 150.0 kg hm(-2) (P < 0.01), and the total saponins content under the nitrogen level of 300.0 kg x hm(-2) was no significant difference compared with that of 262.5 kg x hm(-2). The optimal nitrogen application level of D. styracifolium was 225.0-262.5 kg x hm(-2).

Kirigami-based stretchable lithium-ion batteries

PubMed Central

Song, Zeming; Wang, Xu; Lv, Cheng; An, Yonghao; Liang, Mengbing; Ma, Teng; He, David; Zheng, Ying-Jie; Huang, Shi-Qing; Yu, Hongyu; Jiang, Hanqing

2015-01-01

We have produced stretchable lithium-ion batteries (LIBs) using the concept of kirigami, i.e., a combination of folding and cutting. The designated kirigami patterns have been discovered and implemented to achieve great stretchability (over 150%) to LIBs that are produced by standardized battery manufacturing. It is shown that fracture due to cutting and folding is suppressed by plastic rolling, which provides kirigami LIBs excellent electrochemical and mechanical characteristics. The kirigami LIBs have demonstrated the capability to be integrated and power a smart watch, which may disruptively impact the field of wearable electronics by offering extra physical and functionality design spaces. PMID:26066809

Trace metal mapping by laser-induced breakdown spectroscopy

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

Kaiser, Jozef; Novotny, Dr. Karel; Hrdlicka, A

2012-01-01

Abstract: Laser-Induced Breakdown Spectroscopy (LIBS) is a sensitive optical technique capable of fast multi-elemental analysis of solid, gaseous and liquid samples. The potential applications of lasers for spectrochemical analysis were developed shortly after its invention; however the massive development of LIBS is connected with the availability of powerful pulsed laser sources. Since the late 80s of 20th century LIBS dominated the analytical atomic spectroscopy scene and its application are developed continuously. Here we review the utilization of LIBS for trace elements mapping in different matrices. The main emphasis is on trace metal mapping in biological samples.

Preparation of H-mordenite/MCM-48 composite and its catalytic performance in the alkylation of toluene with tert-butanol

NASA Astrophysics Data System (ADS)

Zhou, Zhiwei; Cheng, Fuling; Qin, Juan; Yu, Pengcheng; Xu, Lin; Gu, Zhiqiang; Liu, Xiaoqin; Wu, Wenliang

2017-09-01

A series of HM/MCM-48 samples with different SiO2/Al2O3 molar ratio were prepared by sol-gel method. The prepared catalysts were characterized by XRD, N2 adsorption-desorption, NH3-TPD, FT-IR, SEM, and TEM techniques, and their catalytic performance was investigated in alkylation of toluene with tert-butanol. The adsorption capacity and the acid sites amount of HM/MCM-48-4 sample prepared by growing MCM-48 on the surface of HM zeolite are much higher than that of their mechanical mixture (HM/MCM-48(4) sample) due to its biporous structure; it shows higher catalytic performance than other HM/MCM-48 samples. The influence of reaction conditions on the catalytic performance of HM/MCM-48-4 zeolite was discussed. Toluene conversion of 41.4% and p-tert-butyltoluene selectivity of 73.5% were obtained at the weight ratio of toluene to HM/MCM-48-4 of 5, reaction temperature of 453 K, reaction time of 5 h and the molar ratio of toluene to tert-butanol of 0.5.

Application of Laser Induced Breakdown Spectroscopy to the identification of emeralds from different synthetic processes

NASA Astrophysics Data System (ADS)

Agrosì, G.; Tempesta, G.; Scandale, E.; Legnaioli, S.; Lorenzetti, G.; Pagnotta, S.; Palleschi, V.; Mangone, A.; Lezzerini, M.

2014-12-01

Laser Induced Breakdown Spectroscopy can provide a useful contribution in mineralogical field in which the quantitative chemical analyses (including the evaluation of light elements) can play a key role in the studies on the origin of the emeralds. In particular, the chemical analyses permit to determine those trace elements, known as fingerprints, that can be useful to study their provenance. This technique, not requiring sample preparation results particularly suitable for gemstones, that obviously must be studied in a non-destructive way. In this paper, the LIBS technique was applied to distinguish synthetic emeralds grown by Biron hydrothermal method from those grown by Chatham flux method. The analyses performed by collinear double-pulse LIBS give a signal enhancement useful for the quantitative chemical analyses while guaranteeing a minimal sample damage. In this way it was obtained a considerable improvement on the detection limit of the trace elements, whose determination is essential for determining the origin of emerald gemstone. The trace elements V, Cr, and Fe and their relative amounts allowed the correct attribution of the manufacturer. Two different methods for quantitative analyses were used for this study: the standard Calibration-Free LIBS (CF-LIBS) method and its recent evolution, the One Point Calibration LIBS (OPC-LIBS). This is the first approach to the evaluation of the emerald origin by means of the LIBS technique.

Optimized laser-induced breakdown spectroscopy for determination of xenobiotic silver in monosodium glutamate and its verification using ICP-AES.

PubMed

Rehan, I; Gondal, M A; Rehan, K

2018-04-20

Laser-induced breakdown spectroscopy (LIBS) was applied as a potential tool for the determination of xenobiotic metal in monosodium glutamate (MSG). In order to achieve a high-sensitivity LIBS system required to determine trace amounts of metallic silver in MSG and to attain the best detection limit, the parameters used in our experiment (impact of focusing laser energy on the intensity of LIBS emission signals, the influence of focusing lens distance on the intensity of LIBS signals, and time responses of the plasma emissions) were optimized. The spectra of MSG were obtained in air using a suitable detector with an optical resolution of 0.06 nm, covering a spectral region from 220 to 720 nm. Along with the detection of xenobiotic silver, other elements such as Ca, Mg, S, and Na were also detected in MSG. To determine the concentration of xenobiotic silver in MSG, the calibration curve was plotted by preparing standard samples having different silver abundances in an MSG matrix. The LIBS results of each sample were cross-verified by analyzing with a standard analytical technique such as inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Both (LIBS and ICP-AES) results were in mutual agreement. The limit of detection of the LIBS setup was found to be 0.57 ppm for silver present in MSG samples.

Theoretical modeling of laser-induced plasmas using the ATOMIC code

NASA Astrophysics Data System (ADS)

Colgan, James; Johns, Heather; Kilcrease, David; Judge, Elizabeth; Barefield, James, II; Clegg, Samuel; Hartig, Kyle

2014-10-01

We report on efforts to model the emission spectra generated from laser-induced breakdown spectroscopy (LIBS). LIBS is a popular and powerful method of quickly and accurately characterizing unknown samples in a remote manner. In particular, LIBS is utilized by the ChemCam instrument on the Mars Science Laboratory. We model the LIBS plasma using the Los Alamos suite of atomic physics codes. Since LIBS plasmas generally have temperatures of somewhere between 3000 K and 12000 K, the emission spectra typically result from the neutral and singly ionized stages of the target atoms. We use the Los Alamos atomic structure and collision codes to generate sets of atomic data and use the plasma kinetics code ATOMIC to perform LTE or non-LTE calculations that generate level populations and an emission spectrum for the element of interest. In this presentation we compare the emission spectrum from ATOMIC with an Fe LIBS laboratory-generated plasma as well as spectra from the ChemCam instrument. We also discuss various physics aspects of the modeling of LIBS plasmas that are necessary for accurate characterization of the plasma, such as multi-element target composition effects, radiation transport effects, and accurate line shape treatments. The Los Alamos National Laboratory is operated by Los Alamos National Security, LLC for the National Nuclear Security Administration of the U.S. Department of Energy under Contract No. DE-AC5206NA25396.

3-hydroxymorphinan is neurotrophic to dopaminergic neurons and is also neuroprotective against LPS-induced neurotoxicity.

PubMed

Zhang, Wei; Qin, Liya; Wang, Tongguang; Wei, Sung-Jen; Gao, Hui-ming; Liu, Jie; Wilson, Belinda; Liu, Bin; Zhang, Wanqin; Kim, Hyoung-Chun; Hong, Jau-Shyong

2005-03-01

The purpose of this study was to develop a novel therapy for Parkinson's disease (PD). We recently reported that dextromethorphan (DM), an active ingredient in a variety of widely used anticough remedies, protected dopaminergic neurons in rat primary mesencephalic neuron-glia cultures against lipopolysaccharide (LPS)-mediated degeneration and provided potent protection for dopaminergic neurons in a MPTP mouse model. The underlying mechanism for the protective effect of DM was attributed to its anti-inflammatory activity through inhibition of microglia activation. In an effort to develop more potent compounds for the treatment of PD, we have screened a series of analogs of DM, and 3-hydroxymorphinan (3-HM) emerged as a promising candidate for this purpose. Our study using primary mesencephalic neuron-glia cultures showed that 3-HM provided more potent neuroprotection against LPS-induced dopaminergic neurotoxicity than its parent compound. The higher potency of 3-HM was attributed to its neurotrophic effect in addition to the anti-inflammatory effect shared by both DM and 3-HM. First, we showed that 3-HM exerted potent neuroprotective and neurotrophic effects on dopaminergic neurons in rat primary mesencephalic neuron-glia cultures treated with LPS. The neurotrophic effect of 3-HM was glia-dependent since 3-HM failed to show any protective effect in the neuron-enriched cultures. We subsequently demonstrated that it was the astroglia, not the microglia, that contributed to the neurotrophic effect of 3-HM. This conclusion was based on the reconstitution studies, in which we added different percentages of microglia (10-20%) or astroglia (40-50%) back to the neuron-enriched cultures and found that 3-HM was neurotrophic after the addition of astroglia, but not microglia. Furthermore, 3-HM-treated astroglia-derived conditioned media exerted a significant neurotrophic effect on dopaminergic neurons. It appeared likely that 3-HM caused the release of neurotrophic factor(s) from astroglia, which in turn was responsible for the neurotrophic effect. Second, the anti-inflammatory mechanism was also important for the neuroprotective activity of 3-HM because the more microglia were added back to the neuron-enriched cultures, the more significant neuroprotective effect was observed. The anti-inflammatory mechanism of 3-HM was attributed to its inhibition of LPS-induced production of an array of pro-inflammatory and neurotoxic factors, including nitric oxide (NO), tumor necrosis factor alpha (TNF-alpha), prostaglandin E2 (PGE2) and reactive oxygen species (ROS). In conclusion, this study showed that 3-HM exerted potent neuroprotection by acting on two different targets: a neurotrophic effect mediated by astroglia and an anti-inflammatory effect mediated by the inhibition of microglial activation. 3-HM thus possesses these two important features necessary for an effective neuroprotective agent. In view of the well-documented very low toxicity of DM and its analogs, this report may provide an important new direction for the development of therapeutic interventions for inflammation-related diseases such as PD.

Laser-Induced Breakdown Spectroscopy for Qualitative Analysis of Metals in Simulated Martian Soils

ERIC Educational Resources Information Center

Mowry, Curtis; Milofsky, Rob; Collins, William; Pimentel, Adam S.

2017-01-01

This laboratory introduces students to laser-induced breakdown spectroscopy (LIBS) for the analysis of metals in soil and rock samples. LIBS employs a laser-initiated spark to induce electronic excitation of metal atoms. Ensuing atomic emission allows for qualitative and semiquantitative analysis. The students use LIBS to analyze a series of…

"Zones of Tolerance" in Perceptions of Library Service Quality: A LibQUAL+[TM] Study.

ERIC Educational Resources Information Center

Cook, Colleen; Heath, Fred M.; Thompson, Bruce

2003-01-01

One of the two major ways of interpreting LibQUAL+[TM] data involves placing perceived service quality ratings within "zones of tolerance" defined as the distances between minimally-acceptable and desired service quality levels. This study compared zones of tolerance on the 25 LibQUAL+[TM] items across undergraduate, graduate student and…

Structure of Perceptions of Service Quality in Libraries: A LibQUAL+ Study.

ERIC Educational Resources Information Center

Thompson, Bruce; Cook, Colleen; Heath, Fred

2003-01-01

Used confirmatory factor analysis to evaluate the score integrity of LibQUALl+, an instrument to measure perceptions of library service quality. Results for 60,027 graduate and undergraduate students suggest that the model implied by LibQUAL is reasonable and invariant across independent samples and fits all three major subgroups of library users.…

New Library, New Librarian, New Student: Using LibGuides to Reach the Virtual Student

ERIC Educational Resources Information Center

Roberts, Sara; Hunter, Dwight

2011-01-01

This article examines the virtual pathfinder and its relationship with distance education students. Various topics are addressed in relation to virtual students, LibGuides and collaborative efforts between librarians and teaching faculty. A brief history of the subject guide is presented, advantages and disadvantages of LibGuides are discussed and…

Selective chemical labeling reveals the genome-wide distribution of 5-hydroxymethylcytosine.

PubMed

Song, Chun-Xiao; Szulwach, Keith E; Fu, Ye; Dai, Qing; Yi, Chengqi; Li, Xuekun; Li, Yujing; Chen, Chih-Hsin; Zhang, Wen; Jian, Xing; Wang, Jing; Zhang, Li; Looney, Timothy J; Zhang, Baichen; Godley, Lucy A; Hicks, Leslie M; Lahn, Bruce T; Jin, Peng; He, Chuan

2011-01-01

In contrast to 5-methylcytosine (5-mC), which has been studied extensively, little is known about 5-hydroxymethylcytosine (5-hmC), a recently identified epigenetic modification present in substantial amounts in certain mammalian cell types. Here we present a method for determining the genome-wide distribution of 5-hmC. We use the T4 bacteriophage β-glucosyltransferase to transfer an engineered glucose moiety containing an azide group onto the hydroxyl group of 5-hmC. The azide group can be chemically modified with biotin for detection, affinity enrichment and sequencing of 5-hmC-containing DNA fragments in mammalian genomes. Using this method, we demonstrate that 5-hmC is present in human cell lines beyond those previously recognized. We also find a gene expression level-dependent enrichment of intragenic 5-hmC in mouse cerebellum and an age-dependent acquisition of this modification in specific gene bodies linked to neurodegenerative disorders.

Different milk feeding intensities during the first 4 weeks of rearing in dairy calves: Part 1: Effects on performance and production from birth over the first lactation.

PubMed

Korst, M; Koch, C; Kesser, J; Müller, U; Romberg, F-J; Rehage, J; Eder, K; Sauerwein, H

2017-04-01

We aimed to test the effects of ad libitum feeding of whole milk (WM) or milk replacer (MR) versus restrictive feeding of MR during the first 4 wk of life on growth performance and on milk yield in the first lactation. We studied 57 German Holstein calves (29 females, 28 males) from birth until d 110 of life (trial 1). The 28 females from trial 1 were further studied during their first lactation (trial 2). In trial 1, all calves were randomly allocated at birth to 1 of 3 groups: MR-res [n = 20, 6.78 kg MR (11.5% solids)/calf per day], MR-ad lib (n = 17, 13.8% solids) or WM-ad lib (n = 20). All calves received colostrum ad libitum from their dam until d 3 of age. From d 4 to 27, calves were fed according to their group regimen. From d 28 to 55, all calves received MR-res feeding and were then gradually weaned until d 69. We recorded body weight (until d 110) and feed intake (amount, metabolizable energy, and frequency of liquid feed intake until weaning). We estimated the profitability of the different feeding regimens, taking into account income from milk yield (trial 2) and feed costs during rearing. In trial 1, the calves from WM-ad lib and MR-ad lib had total metabolizable energy intakes 2.02- and 1.65-fold greater than the MR-res group during the first 4 wk of life. During this period, concentrate intake did not differ among groups, but tended to be greater in WM-ad lib than in MR-ad lib calves from d 28 to 69. The MR-res calves visited the automatic feeders more often than the ad libitum-fed groups during differential feeding, but 70% of the visits were unrewarded (<10% in the ad libitum-fed calves). When all calves were fed at the MR-res level, the average proportion of unrewarded visits was 65% in all groups. Average daily gain and body weight were greater among MR-ad lib and WM-ad lib calves than among MR-res animals during the first 4 wk of life, but not from d 1 to 110. In trial 2, age at first calving, dry matter intake, and body weight over the first 10 mo of lactation were not different among groups, nor was milk composition. Milk yields (305 d) were numerically but not statistically greater in the ad libitum-fed groups during the first lactation (+765 kg for WM-ad lib vs. MR-res; +612 kg for MR-ad lib vs. MR-res). Feeding WM-ad lib and MR-ad lib was 1.37- and 1.21-fold more costly than MR-res, respectively, but amounted to 18, 15, and 13% of the total estimated feed costs until first calving in WM-ad lib, MR-ad lib, and MR-res, respectively. Our study confirms that ad libitum feeding is an attractive measure for rearing dairy calves, both for animal welfare and-with the caveat of a small sample size in trial 2 that led to insufficient power-economic profit from milk. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Spectrochemical analysis of powdered biological samples using transversely excited atmospheric carbon dioxide laser plasma excitation

NASA Astrophysics Data System (ADS)

Zivkovic, Sanja; Momcilovic, Milos; Staicu, Angela; Mutic, Jelena; Trtica, Milan; Savovic, Jelena

2017-02-01

The aim of this study was to develop a simple laser induced breakdown spectroscopy (LIBS) method for quantitative elemental analysis of powdered biological materials based on laboratory prepared calibration samples. The analysis was done using ungated single pulse LIBS in ambient air at atmospheric pressure. Transversely-Excited Atmospheric pressure (TEA) CO2 laser was used as an energy source for plasma generation on samples. The material used for the analysis was a blue-green alga Spirulina, widely used in food and pharmaceutical industries and also in a few biotechnological applications. To demonstrate the analytical potential of this particular LIBS system the obtained spectra were compared to the spectra obtained using a commercial LIBS system based on pulsed Nd:YAG laser. A single sample of known concentration was used to estimate detection limits for Ba, Ca, Fe, Mg, Mn, Si and Sr and compare detection power of these two LIBS systems. TEA CO2 laser based LIBS was also applied for quantitative analysis of the elements in powder Spirulina samples. Analytical curves for Ba, Fe, Mg, Mn and Sr were constructed using laboratory produced matrix-matched calibration samples. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used as the reference technique for elemental quantification, and reasonably well agreement between ICP and LIBS data was obtained. Results confirm that, in respect to its sensitivity and precision, TEA CO2 laser based LIBS can be successfully applied for quantitative analysis of macro and micro-elements in algal samples. The fact that nearly all classes of materials can be prepared as powders implies that the proposed method could be easily extended to a quantitative analysis of different kinds of materials, organic, biological or inorganic.

[An automatic peak detection method for LIBS spectrum based on continuous wavelet transform].

PubMed

Chen, Peng-Fei; Tian, Di; Qiao, Shu-Jun; Yang, Guang

2014-07-01

Spectrum peak detection in the laser-induced breakdown spectroscopy (LIBS) is an essential step, but the presence of background and noise seriously disturb the accuracy of peak position. The present paper proposed a method applied to automatic peak detection for LIBS spectrum in order to enhance the ability of overlapping peaks searching and adaptivity. We introduced the ridge peak detection method based on continuous wavelet transform to LIBS, and discussed the choice of the mother wavelet and optimized the scale factor and the shift factor. This method also improved the ridge peak detection method with a correcting ridge method. The experimental results show that compared with other peak detection methods (the direct comparison method, derivative method and ridge peak search method), our method had a significant advantage on the ability to distinguish overlapping peaks and the precision of peak detection, and could be be applied to data processing in LIBS.

Experimental investigation of effective parameters on signal enhancement in spark assisted laser induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Hassanimatin, M. M.; Tavassoli, S. H.

2018-05-01

A combination of electrical spark and laser induced breakdown spectroscopy (LIBS), which is called spark assisted LIBS (SA-LIBS), has shown its capability in plasma spectral emission enhancement. The aim of this paper is a detailed study of plasma emission to determine the effect of plasma and experimental parameters on increasing the spectral signal. An enhancement ratio of SA-LIBS spectral lines compared with LIBS is theoretically introduced. The parameters affecting the spectral enhancement ratio including ablated mass, plasma temperature, the lifetime of neutral and ionic spectral lines, plasma volume, and electron density are experimentally investigated and discussed. By substitution of the effective parameters, the theoretical spectral enhancement ratio is calculated and compared with the experimental one. Two samples of granite as a dielectric and aluminum as a metal at different laser pulse energies are studied. There is a good agreement between the calculated and the experimental enhancement ratio.

An Analysis of Physician Assistant LibGuides: A Tool for Collection Development.

PubMed

Johnson, Catherine V; Johnson, Scott Y

2017-01-01

The Physician Assistant (PA) specialty encompasses many subject areas and requires many types of library resources. An analysis of PA LibGuides was performed to determine most frequently recommended resources. A sample of LibGuides from U.S. institutions accredited by the Accreditation Review Commission on Education for the Physician Assistant (ARC-PA) was included in this study. Resources presented on guides were tabulated and organized by resource type. Databases and point-of-care tools were the types of resources listed by the most LibGuides. There were over 1,000 books listed on the 45 guides, including over 600 unique books listed. There were fewer journals listed, only 163. Overall, while the 45 LibGuides evaluated list many unique resources in each category, a librarian can create an accepted list of the most frequently listed resources from the data gathered.

The development of lithium ion secondary batteries.

PubMed

Nishi, Y

2001-01-01

Lithium ion secondary batteries (LIBs) were successfully developed as battery systems with high volumetric and gravimetric energy densities, which were inherited from lithium secondary batteries (LSBs) with metallic lithium anodes. LSBs have several drawbacks, however, including poor cyclability and quick-charge rejection. The cell reaction in LIB is merely a topochemical one, namely the migration of lithium ions between positive and negative electroces. No chemical changes were observed in the two electrodes or in the electrolytes. This results in little chemical transformation of the active electrode materials and electrolytes, and thus, LIBs can overcome the weaknesses of LSBs; for example, LIBs show excellent cyclability and quick-charge acceptance. Many difficulties, however, were encountered during the course of development, including capacity fade during cycling and safety issues. This article is the story of the development of LIBs and it describes how the difficulties were surmounted. Copyright 2001 The Japan Chemical Journal Forum and John Wiley & Sons, Inc.

Development of laser-based technology for the routine first wall diagnostic on the tokamak EAST: LIBS and LIAS

NASA Astrophysics Data System (ADS)

Hu, Z.; Gierse, N.; Li, C.; Liu, P.; Zhao, D.; Sun, L.; Oelmann, J.; Nicolai, D.; Wu, D.; Wu, J.; Mao, H.; Ding, F.; Brezinsek, S.; Liang, Y.; Ding, H.; Luo, G.; Linsmeier, C.; EAST Team

2017-12-01

A laser based method combined with spectroscopy, such as laser-induced breakdown spectroscopy (LIBS) and laser-induced ablation spectroscopy (LIAS), is a promising technology for plasma-wall interaction studies. In this work, we report the development of in situ laser-based diagnostics (LIBS and LIAS) for the assessment of static and dynamic fuel retention on the first wall without removing the tiles between and during plasma discharges in the Experimental Advanced Superconducting Tokamak (EAST). The fuel retention on the first wall was measured after different wall conditioning methods and daily plasma discharges by in situ LIBS. The result indicates that the LIBS can be a useful tool to predict the wall condition in EAST. With the successful commissioning of a refined timing system for LIAS, an in situ approach to investigate fuel retention is proposed.

Minimal invasive control of paintings cleaning by LIBS

NASA Astrophysics Data System (ADS)

Staicu, A.; Apostol, I.; Pascu, A.; Urzica, I.; Pascu, M. L.; Damian, V.

2016-03-01

In cultural heritage restoration and conservation, it has been proved that LIBS is an appropriate technique for pigments identification, analysis of multilayered paintings, and quantitative analysis of ancient materials. Generally, experiments involving the use of laser for paint cleaning and LIBS in order to identify the composition of the removed material are made. Here, we report LIBS studies on mastic and dammar varnishes removal using visible (532 nm) and UV (266 nm) laser pulses (5 ns) with fluences in the range 0.6-4.4 J/cm2. The studied varnish layers were on-purpose painted on glass supports or were part of several mock-up samples having dammar or mastic as final layer - gold foil, yellow ochre or cobalt blue egg tempera as painting layer - chalk or acrylic ground as link to an wooden support. LIBS was used to monitor the laser induced stepwise selective removal of the layers and to analyze their composition.

Environmental risk assessment and consequences of municipal solid waste disposal.

PubMed

Vaverková, Magdalena Daria; Elbl, Jakub; Radziemska, Maja; Adamcová, Dana; Kintl, Antonín; Baláková, Ludmila; Bartoň, Stanislav; Hladký, Jan; Kynický, Jindřich; Brtnický, Martin

2018-06-04

Effective and efficient assessments of the site conditions are required for the sustainable management of landfills. In this study we propose an evaluation method to determine the degree of environmental contamination by the contest of heavy metals (HM) concentrations in soil and plants (Tanacetum vulgare L., Carduus L., Plantago major L.). We compared HM concentrations in the soil, leaves, stem and roots of those native plants. Content of HM in samples was at the same level in all localities, except content of Zn. These values confirm that the area is not naturally burdened by increased HM content in the soil, and also that the deposited municipal waste or the material used for reclamation and composting does not contain risk elements. The content of selected HM was monitored in plants naturally occurring in the area of interest. We can state that the content of individual HM was in the plant biomass at the same level. The measured values confirmed that the largest number of HM was in roots, then in stem and the least in leaves. In addition, specific indexes were determined: BAC, TF, CF, PLI and I geo . The BAC values confirmed that the individual plants had the ability to accumulate Pb and Cd (BAC> 2) but were limited to bind Mn and Zn (BAC <1). TF values confirmed that plants had a different ability to transport HM from roots to aboveground biomass. Potential soil contamination was detected using CF, PLI and I geo indexes but contamination by HM was not confirmed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Simultaneous determination of paclitaxel and a new P-glycoprotein inhibitor HM-30181 in rat plasma by liquid chromatography with tandem mass spectrometry.

PubMed

Paek, In Bok; Ji, Hye Young; Kim, Maeng Seop; Lee, Gwan Sun; Lee, Hye Suk

2006-03-01

An LC-MS/MS method for the simultaneous determination of a new P-glycoprotein inhibitor 4-oxo-4H-chromene-2-carboxylic acid [2-(2-(4-[2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl)-ethyl]-phenyl)-2H-tetrazol-5-yl)-4,5-dimethoxy-phenyl]-amide (HM-30181) and a P-glycoprotein substrate paclitaxel in rat plasma was developed to simultaneously evaluate the pharmacokinetics of paclitaxel and HM-30181 in the rats. HM-30181, paclitaxel, HM-30059 (internal standard (I.S.) for HM-30181), and docetaxel (I.S. for paclitaxel) were extracted from rat plasma with methyl-tert-butyl ether and analyzed on an Atlantis C18 column (5 microm, 2.1 x 100 mm) with the mobile phase of ACN/10 mM ammonium formate (75:25 v/v). The analytes were detected using an ESI MS/MS in the multiple reaction monitoring (MRM) mode. The standard curves for HM-30181 and paclitaxel in plasma were linear (r > 0.999) over the concentration range of 2.0-500 ng/mL with a weighting of 1/concentration2. The method showed a satisfactory sensitivity (2 ng/mL using 50 microL plasma), precision (CV: < or = 6.6%), accuracy (relative error: -6.3 to 2.0%), and selectivity. This method was successfully applied to the pharmacokinetic study of HM-30181 and paclitaxel in rat plasma after oral-coadministration of paclitaxel and HM-30181 to male Sprague- Dawley rats.

[Intervention to improve hand hygiene compliance in Catalonia, Spain].

PubMed

Sobrequés, Jordi; Espuñes, Jordi; Bañeres, Joaquim

2014-07-01

Hand hygiene (HM) is the single most important measure and effective in reducing the risk of Healthcare acquired infections (IRAS). Although HM is an effective, simple and cheap measure, it is usual to find results of low compliance among health professionals. The main objective of this strategy has been to give new force to the promotion of HM in hospitals and educate professionals about the importance of this single action. The strategy was planned as a multicenter intervention study to promote HM in health centers of Catalonia in 2009-2010. The intervention is based on 4 main areas: a survey of barriers and facilitators, distribution of graphic material, training at different levels and measure of quality indicators. With this strategy a total of 57% of the number of acute beds in the concerted public and private network of hospitals were reached. The survey revealed that training was perceived as the main facilitator of the HM action. 15,376 professionals registered to the on-line training. The overall compliance with HM indications (based on "five moments for HM") was 56.45% in the acute areas. The campaigns and programs to promote HM carried out in the last four years in Catalonia has helped to achieve an increasing number of hospitals associated to the strategy of the Alliance for Patient Safety in Catalonia. The on-line curse acceptance was very high and seems a powerful tool to improve hand hygiene knowledge and compliance among health professionals. The compliance of HM seems to increase in the hospitals of Catalonia evaluated. Copyright © 2014. Published by Elsevier Espana.

Perceptions and practices regarding herbal medicine prescriptions among physicians in Greater Beirut.

PubMed

Ala Aeddine, Nada; Khayat, Mohamed; Alawieh, Hanaa; Adibilly, Siham; Adib, Salim

2014-01-01

This survey aimed at assessing the perceptions of physicians regarding the appropriateness of prescribing herbal medicines (HM), their prescribing patterns and their knowledge regarding the interaction between HM and conventional drugs. No data are currently available in Lebanon concerning the frequency of HM prescription and indications. HM poorly prescribed can affect the overall quality of health among patients taking conventional drugs. This descriptive survey study was conducted in the Greater Beirut area in Lebanon during May-June 2009. All Primary Health Care (PHC) physicians in private community-based solo practice were identified from the Lebanese Order of Physicians listing, contacted and invited to participate. Those who agreed had to complete a pre-piloted face-to-face questionnaire. Of two hundred twelve participating physicians, 45% routinely prescribed HM to their patients. Between 64 to 67% prescribers believed that HM have more benefits, faster results and fewer side effects than conventional drugs. In addition, 58% thought that HM were less expensive, and 76% that they were easier to take than conventional drugs. More importantly, in a series of eight questions concerning the physicians' knowledge about the possible mechanism of drug-herb interactions, the general tendency was towards poor knowledge. A good percentage of PHC physicians who routinely prescribe HM do not know their mechanism of action or their possible interactions with the conventional drugs. Knowledge about mechanism of drug-herb interactions should be an integral part of the medical curriculum. The knowledge about HM should be an integral part of the medical curriculum as they are frequently prescribed by PHC physicians.

78 FR 65453 - Hazardous Materials: Corrections and Response to Administrative Appeals (HM-215K, HM-215L, HM...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-31

...This final rule corrects editorial errors and amends certain requirements in response to administrative appeals submitted by persons affected by certain final rules published in the Federal Register.

[Carbon storage of forest vegetation and allocation for main forest types in the east of Da-xing'an Mountains based on additive biomass model].

PubMed

Peng, Wei; Dong, Li Hu; Li, Feng Ri

2016-12-01

Based on the biomass investigation data of main forest types in the east of Daxing'an Mountains, the additive biomass models of 3 main tree species were developed and the changes of carbon storage and allocation of forest community of tree layer, shrub layer, herb layer and litter layer from different forest types were discussed. The results showed that the carbon storage of tree layer, shrub layer, herb layer and litter layer for Rhododendron dauricum-Larix gmelinii forest was 71.00, 0.34, 0.05 and 11.97 t·hm -2 , respectively. Similarly, the carbon storage of the four layers of Ledum palustre-L. gmelinii forest was 47.82, 0.88, 0, 5.04 t·hm -2 , 56.56, 0.44, 0.04, 8.72 t·hm -2 for R. dauricum-mixed forest of L. gmelinii-Betula platyphylla, 46.21, 0.66, 0.07, 6.16 t·hm -2 for L. palustre-mixed forest of L. gmelinii-B. platyphylla, 40.90, 1.37, 0.04, 3.67 t·hm -2 for R. dauricum-B. platyphylla forest, 36.28, 1.12, 0.18, 4.35 t·hm -2 for L. palustre-B. platyphylla forest. The carbon storage of forest community for the understory vegetation of R. dauricum was higher than that of the forest with L. palustre. In the condition of similar circumstances for the understory, the order of carbon storage for forest community was L. gmelinii forest > the mixed forest of L. gmelinii-B. platyphylla > B. platyphylla forest. The carbon storage of different forest types was different with the order of R. dauricum-L. gmelinii forest (83.36 t·hm -2 )> R. dauricum-mixed forest of L. gmelinii-B. platyphylla (65.76 t·hm -2 ) > L. palustre-L. gmelinii forest (53.74 t·hm -2 )> L. palustre-mixed forest of L. gmelinii-B. platyphylla (53.10 t·hm -2 )> R. dauricum-B. platyphylla forest (45.98 t·hm -2 ) > L. palustre-B. platyphylla forest (41.93 t·hm -2 ). The order of carbon storage for the vertical distribution in forest communities with diffe-rent forest types was the tree layer (85.2%-89.0%) > litter layer (8.0%-14.4%) > shrub layer (0.4%-2.7%) > herb layer (0-0.4%).

Interaction of HmC1q with leech microglial cells: involvement of C1qBP-related molecule in the induction of cell chemotaxis

PubMed Central

2012-01-01

Background In invertebrates, the medicinal leech is considered to be an interesting and appropriate model to study neuroimmune mechanisms. Indeed, this non-vertebrate animal can restore normal function of its central nervous system (CNS) after injury. Microglia accumulation at the damage site has been shown to be required for axon sprouting and for efficient regeneration. We characterized HmC1q as a novel chemotactic factor for leech microglial cell recruitment. In mammals, a C1q-binding protein (C1qBP alias gC1qR), which interacts with the globular head of C1q, has been reported to participate in C1q-mediated chemotaxis of blood immune cells. In this study, we evaluated the chemotactic activities of a recombinant form of HmC1q and its interaction with a newly characterized leech C1qBP that acts as its potential ligand. Methods Recombinant HmC1q (rHmC1q) was produced in the yeast Pichia pastoris. Chemotaxis assays were performed to investigate rHmC1q-dependent microglia migration. The involvement of a C1qBP-related molecule in this chemotaxis mechanism was assessed by flow cytometry and with affinity purification experiments. The cellular localization of C1qBP mRNA and protein in leech was investigated using immunohistochemistry and in situ hybridization techniques. Results rHmC1q-stimulated microglia migrate in a dose-dependent manner. This rHmC1q-induced chemotaxis was reduced when cells were preincubated with either anti-HmC1q or anti-human C1qBP antibodies. A C1qBP-related molecule was characterized in leech microglia. Conclusions A previous study showed that recruitment of microglia is observed after HmC1q release at the cut end of axons. Here, we demonstrate that rHmC1q-dependent chemotaxis might be driven via a HmC1q-binding protein located on the microglial cell surface. Taken together, these results highlight the importance of the interaction between C1q and C1qBP in microglial activation leading to nerve repair in the medicinal leech. PMID:22356764

Interaction of HmC1q with leech microglial cells: involvement of C1qBP-related molecule in the induction of cell chemotaxis.

PubMed

Tahtouh, Muriel; Garçon-Bocquet, Annelise; Croq, Françoise; Vizioli, Jacopo; Sautière, Pierre-Eric; Van Camp, Christelle; Salzet, Michel; Nagnan-le Meillour, Patricia; Pestel, Joël; Lefebvre, Christophe

2012-02-22

In invertebrates, the medicinal leech is considered to be an interesting and appropriate model to study neuroimmune mechanisms. Indeed, this non-vertebrate animal can restore normal function of its central nervous system (CNS) after injury. Microglia accumulation at the damage site has been shown to be required for axon sprouting and for efficient regeneration. We characterized HmC1q as a novel chemotactic factor for leech microglial cell recruitment. In mammals, a C1q-binding protein (C1qBP alias gC1qR), which interacts with the globular head of C1q, has been reported to participate in C1q-mediated chemotaxis of blood immune cells. In this study, we evaluated the chemotactic activities of a recombinant form of HmC1q and its interaction with a newly characterized leech C1qBP that acts as its potential ligand. Recombinant HmC1q (rHmC1q) was produced in the yeast Pichia pastoris. Chemotaxis assays were performed to investigate rHmC1q-dependent microglia migration. The involvement of a C1qBP-related molecule in this chemotaxis mechanism was assessed by flow cytometry and with affinity purification experiments. The cellular localization of C1qBP mRNA and protein in leech was investigated using immunohistochemistry and in situ hybridization techniques. rHmC1q-stimulated microglia migrate in a dose-dependent manner. This rHmC1q-induced chemotaxis was reduced when cells were preincubated with either anti-HmC1q or anti-human C1qBP antibodies. A C1qBP-related molecule was characterized in leech microglia. A previous study showed that recruitment of microglia is observed after HmC1q release at the cut end of axons. Here, we demonstrate that rHmC1q-dependent chemotaxis might be driven via a HmC1q-binding protein located on the microglial cell surface. Taken together, these results highlight the importance of the interaction between C1q and C1qBP in microglial activation leading to nerve repair in the medicinal leech.

Elliptic net and its cryptographic application

NASA Astrophysics Data System (ADS)

Muslim, Norliana; Said, Mohamad Rushdan Md

2017-11-01

Elliptic net is a generalization of elliptic divisibility sequence and in cryptography field, most cryptographic pairings that are based on elliptic curve such as Tate pairing can be improved by applying elliptic nets algorithm. The elliptic net is constructed by using n dimensional array of values in rational number satisfying nonlinear recurrence relations that arise from elliptic divisibility sequences. The two main properties hold in the recurrence relations are for all positive integers m>n, hm +nhm -n=hm +1hm -1hn2-hn +1hn -1hm2 and hn divides hm whenever n divides m. In this research, we discuss elliptic divisibility sequence associated with elliptic nets based on cryptographic perspective and its possible research direction.

Potential and real ecological threat of heavy metals in contaminated soils

NASA Astrophysics Data System (ADS)

Motuzova, Galina; Barsova, Natalia; Makarichev, Ivan; Karpova, Elena

2013-04-01

Introduction. Microelements or heavy metals (HM) occur in nature and are required for living organisms at low concentrations. High content of HM in soils characterize their potential danger for ecosystem. Their real ecological threat is presented by the mobility of HM in soils. The aim of this work was to characterize the potential and real danger of HM on the basis of HM mobility in soils and their influence of the most important soils properties. Materials and methods. Two types of materials are presented in this paper. The first ones are presented by the summarized information about the content of Cu, Zn, Mn and their mobile species in the soils of Russia and are included into the National Atlas of Russian soils (2011). The second part is presented by the results of laboratory experiments with some samples of Podzols, Podzoluvisol and Chernozem. The following parameters have been determined: a) the main chemical properties of soils; b) the water extracts from soils were investigated by the potentiometric titration with HM salts; c) the properties of the samples of humic acids (HA, extracted by 1n. NaOH) and HA-Cu complexes were determined: molecular-masses distribution (MMD), infrared spectra (IRS), hydrophobility, 1? NMR spectra Results and discussions. The major part of HM in soils of natural landscapes is firmly bound to several minerals. Their threat for living organisms is largely dependent on a relatively higher mobility of HM in soils. The main factors affecting the mobility of HM include soil reaction and sorption processes. In soils of natural landscapes the share of mobile HM compounds is estimated as some per cents from their total content. Having used the data about microelements in soils, their availability to living organisms, 14 natural biogeochemical provinces have been distinguished at the territory of the European part of the former USSR. It permitted to show the adverse impact rendered by microelements at low or high concentrations on living organisms. Within the last 20-40 years a bulk of information has been accumulating to study the impact of technogenic sources on the HM content in soils and the ratio between their compounds. They serve as evidence that in the contaminated soils the total content of HM is several orders (2-3) higher than that in soils of natural landscapes. Based upon a comprehensive analysis of data obtained in field and laboratory it is possible to speak about following differences in soils of natural and technogenic landscapes. (1) The total content of HM in contaminated soils reveals weak connection with their content in soil-forming rocks being depended on technological and landscape-geochemical conditions. (2) A share of mobile forms of HM from their total content increases in comparison to that in natural soils, what is associated with soil contamination and even toxicity, because they can be easily taken up by plants and other living organisms. (3) The surplus of HM in soils leads to degradation of the most important properties so vital for soil fertility (acid base saturation, ion exchange capacity, the humus status, absorbing capacity and others). The enhanced knowledge of soil chemical properties which are subject to contamination by HM, regularities in sorption of heavy metals bond to soil components, the composition of compounds formed by soil with heavy metals allows forecasting the real ecological threat of landscape contamination with HM. The indices of the foregoing soil chemical properties serve as a basis for application of current technologies for soil remediation from HM. Acknowledgments. This work was supported by the Russian Found of Basic Researches (projects no. 06-05-48894, 09-05-00575, 11-05-90351)

Application of the central composite design to optimize the preparation of novel micelles of harmine.

PubMed

Bei, Yong-Yan; Zhou, Xiao-Feng; You, Ben-Gang; Yuan, Zhi-Qiang; Chen, Wei-Liang; Xia, Peng; Liu, Yang; Jin, Yong; Hu, Xiao-Juan; Zhu, Qiao-Ling; Zhang, Chun-Ge; Zhang, Xue-Nong; Zhang, Liang

2013-01-01

Lactose-palmitoyl-trimethyl-chitosan (Lac-TPCS), a novel amphipathic self-assembled polymer, was synthesized for administration of insoluble drugs to reduce their adverse effects. The central composite design was used to study the preparation technique of harmine (HM)-loaded self-assembled micelles based on Lac-TPCS (Lac-TPCS/HM). Three preparation methods and single factors were screened, including solvent type, HM amount, hydration volume, and temperature. The optimal preparation technique was identified after investigating the influence of two independent factors, namely, HM amount and hydration volume, on four indexes, ie, encapsulation efficiency (EE), drug-loading amount (LD), particle size, and polydispersity index (PDI). Analysis of variance showed a high coefficient of determination of 0.916 to 0.994, thus ensuring a satisfactory adjustment of the predicted prescription. The maximum predicted values of the optimal prescription were 91.62%, 14.20%, 183.3 nm, and 0.214 for EE, LD, size, and PDI, respectively, when HM amount was 1.8 mg and hydration volume was 9.6 mL. HM-loaded micelles were successfully characterized by Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and a fluorescence-quenching experiment. Sustained release of Lac-TPCS/HM reached 65.3% in 72 hours at pH 7.4, while free HM released about 99.7% under the same conditions.

Supra-normal age-linked retrograde amnesia: lessons from an older amnesic (H.M.).

PubMed

MacKay, Donald G; Hadley, Christopher

2009-05-01

MacKay and James (2001) demonstrated greater-than-normal retrograde amnesia (RA) for lexical-semantic information in amnesic H.M., a deficit that worsened with aging or represented supranormal age-linked RA (SARA). The present experiments extend these earlier observations to new types of information. Experiment 1 participants (H.M. and carefully matched memory-normal controls) named pictures on the Boston Naming Test and H.M. correctly named reliably fewer pictures with low frequency names, he produced unusual naming errors, and he benefited reliably less than the controls from phonological cues to the target word. Experiment 2 participants recalled irregularly-spelled aspects of familiar words in a two-choice recognition memory task and H.M. chose the correct spelling reliably less often than the controls. Experiment 3 participants read low frequency words aloud at age 73 and H.M. produced reliably more reading errors than the controls. Results of all three experiments indicate supranormal RA (SRA) for information once familiar to H.M. and comparisons with earlier studies using similar or identical stimuli indicated that H.M.'s SRA has worsened with aging from 1980 to 1999. In short, H.M. exhibits SARA for phonological and orthographic information, consistent with the MacKay and James results and with interactions between aging and amnesia predicted under binding theory. Copyright 2008 Wiley-Liss, Inc.

Temperature and Electron Density Determination on Laser-Induced Breakdown Spectroscopy (LIBS) Plasmas: A Physical Chemistry Experiment

ERIC Educational Resources Information Center

Najarian, Maya L.; Chinni, Rosemarie C.

2013-01-01

This laboratory is designed for physical chemistry students to gain experience using laser-induced breakdown spectroscopy (LIBS) in understanding plasma diagnostics. LIBS uses a high-powered laser that is focused on the sample causing a plasma to form. The emission of this plasma is then spectrally resolved and detected. Temperature and electron…

Designing LibGuides as Instructional Tools for Critical Thinking and Effective Online Learning

ERIC Educational Resources Information Center

Baker, Ruth L.

2014-01-01

Did you ever wish for an easy-to-maintain tool to create course-level or assignment-level instruction for online or distance students? LibGuides can provide the solution! LibGuides provide a versatile and easy-to-maintain platform for delivering step-by-step, scaffolded tutorials that enhance learning outcomes through chunking, reduced strain on…

Scaling Users' Perceptions of Library Service Quality Using Item Response Theory: A LibQUAL+ [TM] Study

ERIC Educational Resources Information Center

Wei, Youhua; Thompson, Bruce; Cook, C. Colleen

2005-01-01

LibQUAL+[TM] data to date have not been subjected to the modern measurement theory called polytomous item response theory (IRT). The data interpreted here were collected from 42,090 participants who completed the "American English" version of the 22 core LibQUAL+[TM] items, and 12,552 participants from Australia and Europe who…

76 FR 40935 - Sunshine Act Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-12

.... Claim No. LIB-I-007; 4 p.m. Claim No. LIB-II-007 Friday, July 22, 2011 10 a.m. Claim No. LIB-II-001; 10...) 616-6975. Judith H. Lock, Executive Officer. [FR Doc. 2011-17632 Filed 7-8-11; 4:15 pm] BILLING CODE... FOREIGN CLAIMS SETTLEMENT COMMISSION [F.C.S.C. Meeting and Hearing Notice No. 5-11] Sunshine Act...

Major losses of fat, carbohydrates and energy content of preterm human milk frozen at -80°C.

PubMed

Lev, H M; Ovental, A; Mandel, D; Mimouni, F B; Marom, R; Lubetzky, R

2014-05-01

Long-term storage of human milk (HM) requires freezing at low temperatures, the consequences of which upon macronutrients are unclear. To test the null hypothesis that HM freezing and storage for a range of 1 to 10 weeks at -80 °C does not affect HM fat, protein, lactose and energy contents. Samples of HM were obtained from 20 mothers (60 samples) of preterm infants (25 to 35 weeks gestation), who routinely expressed their milk, every 3 h, using an electric pump, from the second to the seventh week after delivery. All samples were frozen at -80 °C for 8 to 83 days (43.8 days average). After thawing and homogenization, energy and macronutrient contents were measured using an HM analyzer. Fat, carbohydrates and energy contents were significantly lower in thawed HM than in fresh HM (fat, fresh vs thawed: 3.72±1.17 vs 3.36±1.19 g/100 ml, P<0.001; carbohydrates, fresh vs thawed: 5.86±0.71 vs 4.09±0.96 g/100 ml, P<0.001; energy, fresh vs thawed: 64.93±12.97 vs 56.63±16.82 kcal/100 ml, P<0.0001), whereas protein content remained unchanged (protein, fresh vs thawed: 1.14±0.36 vs 1.15±0.37 g/100 ml, P=0.7). The decline in carbohydrates content but not in fat and energy correlated significantly with freezing duration. Freezing at -80 °C significantly decreases the energy content of HM, both from fat and carbohydrates. Since quantitatively the decrease in macronutrients was much higher than that published for HM storage at -20 °C, our results do not support freezing HM at -80 °C as the gold standard for long-term storage. We suggest that caloric intake calculations in preterm infants cannot be established based upon fresh HM data.

Utilization of selected laser-ablation-based diagnostic methods for study of elemental distribution in various solid samples

NASA Astrophysics Data System (ADS)

Kaiser, J.; Novotný, K.; Hrdlička, A.; Malina, R.; Novotný, J.; Prochazka, D.; Petrilak, M.; Krajcarová, L.; Vítková, G.; Kučerová, P.

2010-12-01

Here we report on the recent developments and upgrades of our Laser-Induced Breakdown Spectroscopy setups and their different modification for high-resolution mapping. Mapping capabilities of Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry are compared. The applied improvements as an autofocus algorithm, together with the realization of double-pulse LIBS or combination of LIBS by Laser-Induced Fluorescence Spectroscopy (LIFS) with technique are detailed. The signal enhancement obtained by double-pulse approach is demonstrated. The state of the art on development of portable remote LIBS apparatus is also presented.

Laser spectrum detection methods for substance of Mars surface

NASA Astrophysics Data System (ADS)

Zhang, Dan; Xue, Bin; Zhao, Yi-yi

2014-11-01

The chemical element and mineral rock's abundance and distribution are the basic material of planetary geology evolution research [1], hence preterit detection for composition of Mars surface substance contains both elements sorts and mineral ingredients. This article introduced new ways to detect Mars elements and mineral components, Laser Induced Breakdown Spectroscopy (LIBS) and Raman Spectroscopy (RS) which have distinct advantages, such as work over a long distance, detect rapidly, accuratly and nondestructively. LIBS and RS both use laser excitation to shoot the substance of Mars exciting new wavelengths. The techniques of LIBS and RS in laboratory are mature, besides the technique of LIBS is being used in MSL (Chemcam) now and RS will be used in ExoMars. Comparing LIBS and RS's detection results with XRF and APXS, Mossbauer spectrometer, these existed Mars surface material detection instruments,and the Infrared spectrometer, Mid-IR, they have more accurate detection results. So LIBS and RS are competent for Mars surface substance detection instead of X-ray spectrometer and Mossbauer spectrometer which were already used in 'Viking 1' and 'Opportunity'. Only accurate detection results about Mars surface substance can lead to scientist's right analysis in inversing geological evolution of the planet.

Laser Induced Breakdown Spectroscopy of Glass and Crystal Samples

NASA Astrophysics Data System (ADS)

Sharma, Prakash; Sandoval, Alejandra; Carter, Michael; Kumar, Akshaya

2015-03-01

Different types of quartz crystals and rare earth ions doped glasses have been identified using the laser induced breakdown spectroscopy (LIBS) technique. LIBS is a real time technique, can be used to identify samples in solid, liquid and gas phases. The advantage of LIBS technique is that no sample preparation is required and laser causes extremely minimal damage to the sample surface. The LIBS spectrum of silicate glasses, prepared by sol-gel method and doped with different concentration of rare earth ions, has been recorded. The limit of detection of rare earth ions in glass samples has been calculated. Total 10 spectrums of each sample were recorded and then averaged to get a final spectrum. The ocean optics LIBS2500 plus spectrometer along with a Q- switched Nd: YAG laser (Quantel, Big Sky) were used to record the LIBS spectrum. This spectrometer can analyze the sample in the spectral range of 200 nm to 980 nm. The spectrum was processed by OOILIBS-plus (v1.0) software. This study has application in the industry where different crystals can be easily identified before they go for shaping and polishing. Also, concentration of rare earth ions in glass can be monitored in real time for quality control.

Constitutive behavior and progressive mechanical failure of electrodes in lithium-ion batteries

NASA Astrophysics Data System (ADS)

Zhang, Chao; Xu, Jun; Cao, Lei; Wu, Zenan; Santhanagopalan, Shriram

2017-07-01

The electrodes of lithium-ion batteries (LIB) are known to be brittle and to fail earlier than the separators during an external crush event. Thus, the understanding of mechanical failure mechanism for LIB electrodes (anode and cathode) is critical for the safety design of LIB cells. In this paper, we present experimental and numerical studies on the constitutive behavior and progression of failure in LIB electrodes. Mechanical tests were designed and conducted to evaluate the constitutive properties of porous electrodes. Constitutive models were developed to describe the stress-strain response of electrodes under uniaxial tensile and compressive loads. The failure criterion and a damage model were introduced to model their unique tensile and compressive failure behavior. The failure mechanism of LIB electrodes was studied using the blunt rod test on dry electrodes, and numerical models were built to simulate progressive failure. The different failure processes were examined and analyzed in detail numerically, and correlated with experimentally observed failure phenomena. The test results and models improve our understanding of failure behavior in LIB electrodes, and provide constructive insights on future development of physics-based safety design tools for battery structures under mechanical abuse.

Constitutive behavior and progressive mechanical failure of electrodes in lithium-ion batteries

DOE PAGES

Zhang, Chao; Xu, Jun; Cao, Lei; ...

2017-05-05

The electrodes of lithium-ion batteries (LIB) are known to be brittle and to fail earlier than the separators during an external crush event. Thus, the understanding of mechanical failure mechanism for LIB electrodes (anode and cathode) is critical for the safety design of LIB cells. In this paper, we present experimental and numerical studies on the constitutive behavior and progression of failure in LIB electrodes. Mechanical tests were designed and conducted to evaluate the constitutive properties of porous electrodes. Constitutive models were developed to describe the stress-strain response of electrodes under uniaxial tensile and compressive loads. The failure criterion andmore » a damage model were introduced to model their unique tensile and compressive failure behavior. The failure mechanism of LIB electrodes was studied using the blunt rod test on dry electrodes, and numerical models were built to simulate progressive failure. The different failure processes were examined and analyzed in detail numerically, and correlated with experimentally observed failure phenomena. Finally, the test results and models improve our understanding of failure behavior in LIB electrodes, and provide constructive insights on future development of physics-based safety design tools for battery structures under mechanical abuse.« less

A compact LIBS system for industrial applications

NASA Astrophysics Data System (ADS)

Noharet, B.; Sterner, C.; Irebo, T.; Gurell, J.; Bengtson, A.; Vainik, R.; Karlsson, H.; Illy, E.

2015-03-01

In recent years, laser-induced breakdown spectroscopy (LIBS) has been established as a promising analytical tool for online chemical analysis. The emitted light spectrum is analyzed for instantaneous determination of the elemental composition of the sample, enabling on-line classification of materials. Two major strengths of the technique are the possibilities to perform both fast and remote chemical analysis to determine the elemental composition of the samples under test. In order to reduce the size of LIBS systems, the use of a compact Q-switched diode-pumped solid-state laser (DPSSL) in a LIBS system is evaluated for the industrial sorting of aluminium alloys. The DPSSL, which delivers 150μJ pulses of high beam quality at more than 7KHz repetition rate, provides irradiance on the target that is appropriate for LIBS measurements. The experimental results indicate that alloy classification and quantitative analysis are possible on scrap aluminium samples placed 50 cm apart from the focusing and collecting lenses, without sample preparation. Similar calibration curves and limits of detection are obtained for traditional high-energy low-frequency flashlamp-pumped and low-energy high-frequency diode-pumped lasers, showing the applicability of compact diode-pumped lasers for industrial LIBS applications.

Feasibility of laser-induced breakdown spectroscopy (LIBS) for classification of sea salts.

PubMed

Tan, Man Minh; Cui, Sheng; Yoo, Jonghyun; Han, Song-Hee; Ham, Kyung-Sik; Nam, Sang-Ho; Lee, Yonghoon

2012-03-01

We have investigated the feasibility of laser-induced breakdown spectroscopy (LIBS) as a fast, reliable classification tool for sea salts. For 11 kinds of sea salts, potassium (K), magnesium (Mg), calcium (Ca), and aluminum (Al), concentrations were measured by inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and the LIBS spectra were recorded in the narrow wavelength region between 760 and 800 nm where K (I), Mg (I), Ca (II), Al (I), and cyanide (CN) band emissions are observed. The ICP-AES measurements revealed that the K, Mg, Ca, and Al concentrations varied significantly with the provenance of each salt. The relative intensities of the K (I), Mg (I), Ca (II), and Al (I) peaks observed in the LIBS spectra are consistent with the results using ICP-AES. The principal component analysis of the LIBS spectra provided the score plot with quite a high degree of clustering. This indicates that classification of sea salts by chemometric analysis of LIBS spectra is very promising. Classification models were developed by partial least squares discriminant analysis (PLS-DA) and evaluated. In addition, the Al (I) peaks enabled us to discriminate between different production methods of the salts. © 2012 Society for Applied Spectroscopy

Monitoring of toxic elements present in sludge of industrial waste using CF-LIBS.

PubMed

Kumar, Rohit; Rai, Awadhesh K; Alamelu, Devanathan; Aggarwal, Suresh K

2013-01-01

Industrial waste is one of the main causes of environmental pollution. Laser-induced breakdown spectroscopy (LIBS) was applied to detect the toxic metals in the sludge of industrial waste water. Sludge on filter paper was obtained after filtering the collected waste water samples from different sections of a water treatment plant situated in an industrial area of Kanpur City. The LIBS spectra of the sludge samples were recorded in the spectral range of 200 to 500 nm by focusing the laser light on sludge. Calibration-free laser-induced breakdown spectroscopy (CF-LIBS) technique was used for the quantitative measurement of toxic elements such as Cr and Pb present in the sample. We also used the traditional calibration curve approach to quantify these elements. The results obtained from CF-LIBS are in good agreement with the results from the calibration curve approach. Thus, our results demonstrate that CF-LIBS is an appropriate technique for quantitative analysis where reference/standard samples are not available to make the calibration curve. The results of the present experiment are alarming to the people living nearby areas of industrial activities, as the concentrations of toxic elements are quite high compared to the admissible limits of these substances.

A matrix effect and accuracy evaluation for the determination of elements in milk powder LIBS and laser ablation/ICP-OES spectrometry.

PubMed

Gilon, N; El-Haddad, J; Stankova, A; Lei, W; Ma, Q; Motto-Ros, V; Yu, J

2011-11-01

Laser ablation coupled to inductively coupled plasma optical emission spectrometry (LA-ICP-OES) and laser-induced breakdown spectroscopy (LIBS) were investigated for the determination of Ca, Mg, Zn and Na in milk samples. The accuracy of both methods was evaluated by comparison of the concentration found using LA-ICP-OES and LIBS with classical wet digestion associated with ICP-OES determination. The results were not fully acceptable, with biases from less than 1% to more than 60%. Matrix effects were also investigated. The sample matrix can influence the temperature, electron number density (n (e)) and other excitation characteristics in the ICP. These ICP characteristics were studied and evaluated during ablation of eight milk samples. Differences in n (e) (from 8.9 to 13.8 × 10(14) cm(-3)) and rotational temperature (ranging from 3,400 to 4,400 K) occurred with no correlation with trueness. LIBS results obtained after classical external calibration procedure gave degraded accuracy, indicating a strong matrix effect. The LIBS measurements clearly showed that the major problem in LA-ICP was related to the ablation process and that LIBS spectroscopy is an excellent diagnostic tool for LA-ICP techniques.

Novel approach to recover cobalt and lithium from spent lithium-ion battery using oxalic acid.

PubMed

Zeng, Xianlai; Li, Jinhui; Shen, Bingyu

2015-09-15

With the booming of consumer electronics (CE) and electric vehicle (EV), a large number of spent lithium-ion battery (LIBs) have been generated worldwide. Resource depletion and environmental concern driven from the sustainable industry of CE and EV have motivated spent LIBs should be recovered urgently. However, the conventional process combined with leaching, precipitating, and filtering was quite complicated to recover cobalt and lithium from spent LIBs. In this work, we developed a novel recovery process, only combined with oxalic acid leaching and filtering. When the optimal parameters for leaching process is controlled at 150 min retention time, 95 °C heating temperature, 15 g L(-1) solid-liquid ratio, and 400 rpm rotation rate, the recovery rate of lithium and cobalt from spent LIBs can reach about 98% and 97%, respectively. Additionally, we also tentatively discovered the leaching mechanism of lithium cobalt oxide (LiCoO2) using oxalic acid, and the leaching order of the sampling LiCoO2 of spent LIBs. All the obtained results can contribute to a short-cut and high-efficiency process of spent LIBs recycling toward a sound closed-loop cycle. Copyright © 2015 Elsevier B.V. All rights reserved.

Inhibition of Growth and Metastasis of Ovarian Carcinoma by Administering a Drug Capable of Interfering with Vascular Endothelial Growth Factor Activity

PubMed Central

Mu, Jie; Abe, Yoshiko; Tsutsui, Tateki; Yamamoto, Norihiko; Tai, Xu‐Guang; Niwa, Ohtsura; Tsujimura, Takahiro; Sato, Bunzo; Terano, Hiroshi; Hamaoka, Toshiyuki

1996-01-01

The present study investigates the relationship between in vivo growth/metastasis of tumor cells and their capacity to produce the vascular endothelial growth factor (VEGF), as well as the regulation of tumor growth/metastasis using an angiogenesis‐inhibitory drug. Two cloned tumor cell lines designated OV‐LM and OV‐HM were isolated from a murine ovarian carcinoma OV2944. OV‐LM and OV‐HM cells grew in cultures at comparable rates. However, when transplanted s.c. into syngeneic mice, OV‐HM exhibited a faster growth rate and a much higher incidence of metastasis to lymph nodes and lung. Histologically, intense neovascularization was detected in sections of OV‐HM but not of OV‐LM tumor. OV‐HM and OV‐LM tumor cells obtained from in vitro cultures expressed high and low levels of VEGF mRNA, respectively. A difference in VEGF mRNA expression was much more clearly observed between RNAs prepared from fresh OV‐HM and OV‐LM tumor masses: RNA from OV‐HM contained larger amounts of VEGF mRNA, whereas RNA from OV‐LM exhibited only marginal levels of VEGF mRNA. An angiogenesis‐inhibitory drug, FR118487 inhibited the VEGF‐mediated in vitro growth of endothelial cells but did not affect the expression in vitro of VEGF mRNA by OV‐HM tumor cells. Intraperitoneal injections of FR118487 into mice bearing OV‐HM tumors resulted in: (i) a subsequent growth inhibition of primary tumors; (ii) a marked decrease in neovascularization inside tumor masses expressing comparable levels of VEGF mRNA to those detected in control OV‐HM masses; and (iii) almost complete inhibition of metastasis to lymph nodes and lung. These results indicate that growth/metastasis of tumor cells correlates with their VEGF‐producing capacity and that an angiogenesis inhibitor, FR118487, inhibits tumor growth and metastasis through mechanism(s) including the suppression of VEGF function in vivo. PMID:8878460

Reducing soil erosion and nutrient loss on sloping land under crop-mulberry management system.

PubMed

Fan, Fangling; Xie, Deti; Wei, Chaofu; Ni, Jiupai; Yang, John; Tang, Zhenya; Zhou, Chuan

2015-09-01

Sloping croplands could result in soil erosion, which leads to non-point source pollution of the aquatic system in the Three Gorges Reservoir Region. Mulberry, a commonly grown cash plant in the region, is traditionally planted in contour hedgerows as an effective management practice to control soil erosion and non-point source pollution. In this field study, surface runoff and soil N and P loss on sloping land under crop-mulberry management were investigated. The experiments consisted of six crop-mulberry treatments: Control (no mulberry hedgerow with mustard-corn rotation); T1 (two-row contour mulberry with mustard-corn rotation); T2 (three-row contour mulberry with mustard-corn rotation); T3 (border mulberry and one-row contour mulberry with mustard-corn rotation); T4 (border mulberry with mustard-corn rotation); T5 (two-row longitudinal mulberry with mustard). The results indicated that crop-mulberry systems could effectively reduce surface runoff and soil and nutrient loss from arable slope land. Surface runoff from T1 (342.13 m(3) hm(-2)), T2 (260.6 m(3) hm(-2)), T3 (113.13 m(3) hm(-2)), T4 (114 m(3) hm(-2)), and T5 (129 m(3) hm(-2)) was reduced by 15.4, 35.6, 72.0, 71.8, and 68.1%, respectively, while soil loss from T1 (0.21 t hm(-2)), T2 (0.13 t hm(-2)), T3 (0.08 t hm(-2)), T4 (0.11 t hm(-2)), and T5 (0.12 t hm(-2)) was reduced by 52.3, 70.5, 81.8, 75.0, and 72.7%, respectively, as compared with the control. Crop-mulberry ecosystem would also elevate soil N by 22.3% and soil P by 57.4%, and soil nutrient status was contour-line dependent.

Tripling of Methamphetamine/Amphetamine Use among Homeless and Marginally Housed Persons, 1996–2003

PubMed Central

Colfax, Grant; Moss, Andrew R.; Bangsberg, David R.; Hahn, Judith A.

2007-01-01

Methamphetamine/amphetamine (MA)-related morbidity and mortality has been increasing in the United States. MA use is associated with high-risk sexual behavior and syringe-sharing practices. Homeless and marginalized housed persons (H/M) have high rates of substance use and mental health disorders. Little is known about trends of MA use among the H/M. The objective of this study was to quantify increases in MA use among H/M in San Francisco and to determine which demographic and behavioral subgroups have experienced the greatest increases in MA use. We conducted serial cross-sectional population-based studies in three waves: 1996–1997, 1999–2000, and 2003 and studied 2,348 H/M recruited at shelters and lunch lines. The main outcome was self-reported current (30-day) MA use. We found a tripling of current MA use among H/M persons from 1996 to 2003, with a sevenfold increase in smoked MA use. MA use doubled to tripled in most demographic and behavioral subgroups, whereas it quadrupled in those under age 35, and there was a fivefold increase among HIV-infected persons. The increase in MA use among H/M places a vulnerable population at additional increased risk for HIV infection and MA-use related morbidity and mortality. Among HIV-infected H/M, the increase in MA use has important public health implications for the development and secondary transmission of drug-resistant HIV caused by synergistic neurocognitive decline, poor adherence to HIV medications, and increased sexual risk behavior. Clinicians caring for H/M persons should inquire about MA use, refer interested MA users to MA dependence treatment programs and provide targeted HIV sexual risk reduction counseling. For HIV-infected H/M MA users, clinicians should closely monitor adherence to HIV or other chronic medications, to avoid unnecessary morbidity and mortality. Further research is needed to elucidate the most effective prevention and treatment for MA use and dependence among the H/M. PMID:18163214

alpha-Galactosylceramide-loaded, antigen-expressing B cells prime a wide spectrum of antitumor immunity.

PubMed

Kim, Yeon-Jeong; Ko, Hyun-Jeong; Kim, Yun-Sun; Kim, Dong-Hyeon; Kang, Seock; Kim, Jong-Mook; Chung, Yeonseok; Kang, Chang-Yuil

2008-06-15

Most of the current tumor vaccines successfully elicit strong protection against tumor but offer little therapeutic effect against existing tumors, highlighting the need for a more effective vaccine strategy. Vaccination with tumor antigen-presenting cells can induce antitumor immune responses. We have previously shown that NKT-licensed B cells prime cytotoxic T lymphocytes (CTLs) with epitope peptide and generate prophylactic/therapeutic antitumor effects. To extend our B cell vaccine approach to the whole antigen, and to overcome the MHC restriction, we used a nonreplicating adenovirus to transduce B cells with antigenic gene. Primary B cells transduced with an adenovirus-encoding truncated Her-2/neu (AdHM) efficiently expressed Her-2/neu. Compared with the moderate antitumor activity induced by vaccination with adenovirus-transduced B cells (B/AdHM), vaccination with alpha-galactosylceramide-loaded B/AdHM (B/AdHM/alpha GalCer) induced significantly stronger antitumor immunity, especially in the tumor-bearing mice. The depletion study showed that CD4(+), CD8(+) and NK cells were all necessary for the therapeutic immunity. Confirming the results of the depletion study, B/AdHM/alpha GalCer vaccination induced cytotoxic NK cell responses but B/AdHM did not. Vaccination with B/AdHM/alpha GalCer generated Her-2/neu-specific antibodies more efficiently than B/AdHM immunization. More importantly, B/AdHM/alpha GalCer could prime Her-2/neu-specific cytotoxic T cells more efficiently and durably than B/AdHM. CD4(+) cells appeared to be necessary for the induction of antibody and CTL responses. Our results demonstrate that, with the help of NKT cells, antigen-transduced B cells efficiently induce innate immunity as well as a wide range of adaptive immunity against the tumor, suggesting that they could be used to develop a novel cellular vaccine. (c) 2008 Wiley-Liss, Inc.

Design optimization of Cassegrain telescope for remote explosive trace detection

NASA Astrophysics Data System (ADS)

Bhavsar, Kaushalkumar; Eseller, K. E.; Prabhu, Radhakrishna

2017-10-01

The past three years have seen a global increase in explosive-based terror attacks. The widespread use of improvised explosives and anti-personnel landmines have caused thousands of civilian casualties across the world. Current scenario of globalized civilization threat from terror drives the need to improve the performance and capabilities of standoff explosive trace detection devices to be able to anticipate the threat from a safe distance to prevent explosions and save human lives. In recent years, laser-induced breakdown spectroscopy (LIBS) is an emerging approach for material or elemental investigations. All the principle elements on the surface are detectable in a single measurement using LIBS and hence, a standoff LIBS based method has been used to remotely detect explosive traces from several to tens of metres distance. The most important component of LIBS based standoff explosive trace detection system is the telescope which enables remote identification of chemical constituents of the explosives. However, in a compact LIBS system where Cassegrain telescope serves the purpose of laser beam delivery and light collection, need a design optimization of the telescope system. This paper reports design optimization of a Cassegrain telescope to detect explosives remotely for LIBS system. A design optimization of Schmidt corrector plate was carried out for Nd:YAG laser. Effect of different design parameters was investigated to eliminate spherical aberration in the system. Effect of different laser wavelengths on the Schmidt corrector design was also investigated for the standoff LIBS system.

Parametric study of a fiber-optic laser-induced breakdown spectroscopy probe for analysis of aluminum alloys

NASA Astrophysics Data System (ADS)

Rai, Awadhesh K.; Zhang, Hansheng; Yueh, Fang Yu; Singh, Jagdish P.; Weisberg, Arel

2001-12-01

In the present work we demonstrate a fiber-optic laser-induced breakdown spectroscopy (FO LIBS) system for delivering laser energy to a sample surface to produce a spark as well as to collect the resulting radiation from the laser-induced spark. In order to improve the signal/background (S/B) ratio, various experimental parameters, such as laser energy, gate delay and width, detector gain, lenses of different focal lengths and sample surface, were tested. In order to provide high reliability and repeatability in the analysis, we also measured plasma parameters, such as electron density and plasma temperature, and determined their influence on the measurement results. The performance of FO LIBS was also compared with that of a LIBS system that does not use a fiber to transmit the laser beam. LIBS spectra with a good S/B were recorded at 2-μs gate delay and width. LIBS spectra of six different Al alloy samples were recorded to obtain calibration data. We were able to obtain linear calibration data for numerous elements (Cr, Zn, Fe, Ni, Mn, Mg and Cu). A linear calibration curve for LIBS intensity ratio vs. concentration ratio reduces the effect of physical variables (i.e. shot-to-shot power fluctuation, sample-to-surface distance, and physical properties of the samples). Our results reveal that this system may be useful in designing a high-temperature LIBS probe for measuring the elemental composition of Al melt.

LIBS: a potential tool for industrial/agricultural waste water analysis

NASA Astrophysics Data System (ADS)

Karpate, Tanvi; K. M., Muhammed Shameem; Nayak, Rajesh; V. K., Unnikrishnan; Santhosh, C.

2016-04-01

Laser Induced Breakdown Spectroscopy (LIBS) is a multi-elemental analysis technique with various advantages and has the ability to detect any element in real time. This technique holds a potential for environmental monitoring and various such analysis has been done in soil, glass, paint, water, plastic etc confirms the robustness of this technique for such applications. Compared to the currently available water quality monitoring methods and techniques, LIBS has several advantages, viz. no need for sample preparation, fast and easy operation, and chemical free during the process. In LIBS, powerful pulsed laser generates plasma which is then analyzed to get quantitative and qualitative details of the elements present in the sample. Another main advantage of LIBS technique is that it can perform in standoff mode for real time analysis. Water samples from industries and agricultural strata tend to have a lot of pollutants making it harmful for consumption. The emphasis of this project is to determine such harmful pollutants present in trace amounts in industrial and agricultural wastewater. When high intensity laser is made incident on the sample, a plasma is generated which gives a multielemental emission spectra. LIBS analysis has shown outstanding success for solids samples. For liquid samples, the analysis is challenging as the liquid sample has the chances of splashing due to the high energy of laser and thus making it difficult to generate plasma. This project also deals with determining the most efficient method for testing of water sample for qualitative as well as quantitative analysis using LIBS.

Quantitative LIBS analysis of vanadium in samples of hexagonal mesoporous silica catalysts.

PubMed

Pouzar, Miloslav; Kratochvíl, Tomás; Capek, Libor; Smoláková, Lucie; Cernohorský, Tomás; Krejcová, Anna; Hromádko, Ludek

2011-02-15

The method for the analysis of vanadium in hexagonal mesoporous silica (V-HMS) catalysts using Laser Induced Breakdown Spectrometry (LIBS) was suggested. Commercially available LIBS spectrometer was calibrated with the aid of authentic V-HMS samples previously analyzed by ICP OES after microwave digestion. Deposition of the sample on the surface of adhesive tape was adopted as a sample preparation method. Strong matrix effect connected with the catalyst preparation technique (1st vanadium added in the process of HMS synthesis, 2nd already synthesised silica matrix was impregnated by vanadium) was observed. The concentration range of V in the set of nine calibration standards was 1.3-4.5% (w/w). Limit of detection was 0.13% (w/w) and it was calculated as a triple standard deviation from five replicated determinations of vanadium in the real sample with a very low vanadium concentration. Comparable results of LIBS and ED XRF were obtained if the same set of standards was used for calibration of both methods and vanadium was measured in the same type of real samples. LIBS calibration constructed using V-HMS-impregnated samples failed for measuring of V-HMS-synthesized samples. LIBS measurements seem to be strongly influenced with different chemical forms of vanadium in impregnated and synthesised samples. The combination of LIBS and ED XRF is able to provide new information about measured samples (in our case for example about procedure of catalyst preparation). Copyright © 2010 Elsevier B.V. All rights reserved.

Laser-induced breakdown spectroscopy is a reliable method for urinary stone analysis

PubMed Central

Mutlu, Nazım; Çiftçi, Seyfettin; Gülecen, Turgay; Öztoprak, Belgin Genç; Demir, Arif

2016-01-01

Objective We compared laser-induced breakdown spectroscopy (LIBS) with the traditionally used and recommended X-ray diffraction technique (XRD) for urinary stone analysis. Material and methods In total, 65 patients with urinary calculi were enrolled in this prospective study. Stones were obtained after surgical or extracorporeal shockwave lithotripsy procedures. All stones were divided into two equal pieces. One sample was analyzed by XRD and the other by LIBS. The results were compared by the kappa (κ) and Spearman’s correlation coefficient (rho) tests. Results Using LIBS, 95 components were identified from 65 stones, while XRD identified 88 components. LIBS identified 40 stones with a single pure component, 20 stones with two different components, and 5 stones with three components. XRD demonstrated 42 stones with a single component, 22 stones with two different components, and only 1 stone with three different components. There was a strong relationship in the detection of stone types between LIBS and XRD for stones components (Spearman rho, 0.866; p<0.001). There was excellent agreement between the two techniques among 38 patients with pure stones (κ index, 0.910; Spearman rho, 0.916; p<0.001). Conclusion Our study indicates that LIBS is a valid and reliable technique for determining urinary stone composition. Moreover, it is a simple, low-cost, and nondestructive technique. LIBS can be safely used in routine daily practice if our results are supported by studies with larger numbers of patients. PMID:27011877

Metabolomic Approaches to Explore Chemical Diversity of Human Breast-Milk, Formula Milk and Bovine Milk

PubMed Central

Qian, Linxi; Zhao, Aihua; Zhang, Yinan; Chen, Tianlu; Zeisel, Steven H.; Jia, Wei; Cai, Wei

2016-01-01

Although many studies have been conducted on the components present in human breast milk (HM), research on the differences of chemical metabolites between HM, bovine milk (BM) and formula milk (FM) is limited. This study was to explore the chemical diversity of HM, BM and FM by metabolomic approaches. GC-TOFMS and UPLC-QTOFMS were applied to investigate the metabolic compositions in 30 HM samples, 20 FM samples and 20 BM samples. Metabolite profiling identified that most of the non-esterified fatty acids, which reflected the hydrolysis of triglycerides, were much more abundant in HM than those in FM and BM, except for palmitic acid and stearic acid. The levels of tricarboxylic acid (TCA) intermediates were much higher in FM and BM than those in HM. Each type of milk also showed its unique composition of free amino acids and free carbohydrates. In conclusion, higher levels of non-esterified saturated fatty acids with aliphatic tails <16 carbons, monounsaturated fatty acids and polyunsaturated fatty acids and lower levels of TCA intermediates are characteristic of HM, as compared with FM and BM. The content of non-esterified fatty acids may reflect the hydrolysis of triglycerides in different milk types. PMID:27999311

Homologous ELISA for detection of oligomeric human TNF: properties of the assay.

PubMed

Petyovka, N; Lyach, L; Voitenok, N N

1995-10-26

In order to quantify oligomeric human tumor necrosis factor-alpha (TNF), we have developed a sensitive homologous enzyme-linked immunosorbent assay (Hm-ELISA) using the same monoclonal antibody (MoAb) for both solid and liquid phase. Different anti-TNF MoAb have been compared in terms of their efficacy in the Hm-ELISA, affinity, neutralization capacity and epitope specificity. The data suggest, that effectiveness in the Hm-ELISA may represent a novel characteristic of MoAb. Of the MoAbs tested, 5 N was capable of recognizing oligomeric TNF in the Hm-ELISA with a detection limit of 15 pg/ml. Furthermore, using Hm-ELISA against human TNF, interleukin-8 (IL-8) and lymphotoxin, we have demonstrated that these cytokines are oligomeric in physiological solutions, but are converted into monomeric forms in the presence of the non-ionic detergent Tween 20. High salt buffer was employed to abrogate a nonspecific false positive reaction in the Hm-ELISA found in nearly half of the plasma samples obtained from healthy subjects. Finally, a good correlation between the Hm-ELISA and the L929 bioassay was observed for natural and recombinant TNF measured in human plasma.

First-principles calculated decomposition pathways for LiBH 4 nanoclusters

DOE PAGES

Huang, Zhi -Quan; Chen, Wei -Chih; Chuang, Feng -Chuan; ...

2016-05-18

Here, we analyze thermodynamic stability and decomposition pathways of LiBH 4 nanoclusters using grand-canonical free-energy minimization based on total energies and vibrational frequencies obtained from density-functional theory (DFT) calculations. We consider (LiBH 4) n nanoclusters with n = 2 to 12 as reactants, while the possible products include (Li) n, (B) n, (LiB) n, (LiH) n, and Li 2B nH n; off-stoichiometric LinBnHm (m ≤ 4n) clusters were considered for n = 2, 3, and 6. Cluster ground-state configurations have been predicted using prototype electrostatic ground-state (PEGS) and genetic algorithm (GA) based structural optimizations. Free-energy calculations show hydrogen release pathwaysmore » markedly differ from those in bulk LiBH 4. While experiments have found that the bulk material decomposes into LiH and B, with Li 2B 12H 12 as a kinetically inhibited intermediate phase, (LiBH 4) n nanoclusters with n ≤ 12 are predicted to decompose into mixed Li nB n clusters via a series of intermediate clusters of Li nB nH m (m ≤ 4n). The calculated pressure-composition isotherms and temperature-pressure isobars exhibit sloping plateaus due to finite size effects on reaction thermodynamics. Generally, decomposition temperatures of free-standing clusters are found to increase with decreasing cluster size due to thermodynamic destabilization of reaction products.« less

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

Huang, Zhi -Quan; Chen, Wei -Chih; Chuang, Feng -Chuan

Here, we analyze thermodynamic stability and decomposition pathways of LiBH 4 nanoclusters using grand-canonical free-energy minimization based on total energies and vibrational frequencies obtained from density-functional theory (DFT) calculations. We consider (LiBH 4) n nanoclusters with n = 2 to 12 as reactants, while the possible products include (Li) n, (B) n, (LiB) n, (LiH) n, and Li 2B nH n; off-stoichiometric LinBnHm (m ≤ 4n) clusters were considered for n = 2, 3, and 6. Cluster ground-state configurations have been predicted using prototype electrostatic ground-state (PEGS) and genetic algorithm (GA) based structural optimizations. Free-energy calculations show hydrogen release pathwaysmore » markedly differ from those in bulk LiBH 4. While experiments have found that the bulk material decomposes into LiH and B, with Li 2B 12H 12 as a kinetically inhibited intermediate phase, (LiBH 4) n nanoclusters with n ≤ 12 are predicted to decompose into mixed Li nB n clusters via a series of intermediate clusters of Li nB nH m (m ≤ 4n). The calculated pressure-composition isotherms and temperature-pressure isobars exhibit sloping plateaus due to finite size effects on reaction thermodynamics. Generally, decomposition temperatures of free-standing clusters are found to increase with decreasing cluster size due to thermodynamic destabilization of reaction products.« less

A fast and efficient python library for interfacing with the Biological Magnetic Resonance Data Bank.

PubMed

Smelter, Andrey; Astra, Morgan; Moseley, Hunter N B

2017-03-17

The Biological Magnetic Resonance Data Bank (BMRB) is a public repository of Nuclear Magnetic Resonance (NMR) spectroscopic data of biological macromolecules. It is an important resource for many researchers using NMR to study structural, biophysical, and biochemical properties of biological macromolecules. It is primarily maintained and accessed in a flat file ASCII format known as NMR-STAR. While the format is human readable, the size of most BMRB entries makes computer readability and explicit representation a practical requirement for almost any rigorous systematic analysis. To aid in the use of this public resource, we have developed a package called nmrstarlib in the popular open-source programming language Python. The nmrstarlib's implementation is very efficient, both in design and execution. The library has facilities for reading and writing both NMR-STAR version 2.1 and 3.1 formatted files, parsing them into usable Python dictionary- and list-based data structures, making access and manipulation of the experimental data very natural within Python programs (i.e. "saveframe" and "loop" records represented as individual Python dictionary data structures). Another major advantage of this design is that data stored in original NMR-STAR can be easily converted into its equivalent JavaScript Object Notation (JSON) format, a lightweight data interchange format, facilitating data access and manipulation using Python and any other programming language that implements a JSON parser/generator (i.e., all popular programming languages). We have also developed tools to visualize assigned chemical shift values and to convert between NMR-STAR and JSONized NMR-STAR formatted files. Full API Reference Documentation, User Guide and Tutorial with code examples are also available. We have tested this new library on all current BMRB entries: 100% of all entries are parsed without any errors for both NMR-STAR version 2.1 and version 3.1 formatted files. We also compared our software to three currently available Python libraries for parsing NMR-STAR formatted files: PyStarLib, NMRPyStar, and PyNMRSTAR. The nmrstarlib package is a simple, fast, and efficient library for accessing data from the BMRB. The library provides an intuitive dictionary-based interface with which Python programs can read, edit, and write NMR-STAR formatted files and their equivalent JSONized NMR-STAR files. The nmrstarlib package can be used as a library for accessing and manipulating data stored in NMR-STAR files and as a command-line tool to convert from NMR-STAR file format into its equivalent JSON file format and vice versa, and to visualize chemical shift values. Furthermore, the nmrstarlib implementation provides a guide for effectively JSONizing other older scientific formats, improving the FAIRness of data in these formats.

LAMELLAR HOLE-ASSOCIATED EPIRETINAL PROLIFERATION IN LAMELLAR MACULAR HOLE AND FULL-THICKNESS MACULAR HOLE IN HIGH MYOPIA.

PubMed

Lai, Tso-Ting; Yang, Chung-May

2017-05-18

To report findings and surgical outcomes of lamellar macular hole (LMH) or full-thickness macular hole (FTMH) accompanied by lamellar hole-associated epiretinal proliferation (LHEP) in eyes with high myopia (HM). Consecutive cases of HM with LMH or FTMH containing LHEP were retrospectively reviewed (study group, 43 cases). Cases of HM without LHEP (22) and those of non-HM with LHEP (30) served as Control A and B. The study group showed larger (928.7 ± 381.9 μm) and deeper (remained base thickness: 79.7 ± 23.7 μm) LMH retinal defect than that in Control A (466.2 ± 179.1 and 99.9 ± 24.9) and B (647.1 ± 346.7 and 99.1 ± 38.1). Lamellar hole-associated epiretinal proliferation in the study group had a higher rate of wide extension (42.3%) and growing along the posterior hyaloid (PH, 53.8%). Patients with LMH who underwent surgery in the study group and Control A showed limited best corrected visual acuity (BCVA) improvement (0-1 and 1-2 ETDRS lines, respectively), while Control B had significant improvement (4-5 lines). For full-thickness macular holes, the study group was the youngest (50.0 ± 11.4) and LHEP was more likely to grow on the posterior hyaloid (23.5%); the postoperative best corrected visual acuity, however, was similar to that in Control A (20/63-20/80). Lamellar hole-associated epiretinal proliferation in HM tended to be more widespread and adherent to the posterior hyaloid than in eyes without HM. Visual outcomes after LMH repair in eyes with LHEP and HM are less favorable than eyes with LHEP and without HM, but similar to eyes with HM and without LHEP.

5-Hydroxymethylcytosine Promotes Proliferation of Human Uterine Leiomyoma: A Biological Link to a New Epigenetic Modification in Benign Tumors

PubMed Central

Navarro, Antonia; Yin, Ping; Ono, Masanori; Monsivais, Diana; Moravek, Molly B.; Coon, John S.; Dyson, Matthew T.; Wei, Jian-Jun

2014-01-01

Context: Uterine leiomyoma, or fibroids, represent the most common benign tumors of the female reproductive tract. A newly discovered epigenetic modification, 5-hydroxymethylation (5-hmC), and its regulators, the TET (Ten Eleven Translocation) enzymes, were implicated in the pathology of malignant tumors; however, their roles in benign tumors, including uterine fibroids, remain unknown. Objective: To determine the role of 5-hmC and TET proteins in the pathogenesis of leiomyoma using human uterine leiomyoma and normal matched myometrial tissues and primary cells. Design: 5-hmC levels were determined by ELISA and immunofluorescent staining in matched myometrial and leiomyoma tissues. TET expression was analyzed by quantitative RT-PCR and immunoblotting. TET1 or TET3 were silenced or inhibited by small interfering RNA or 2-hydroxyglutarate to study their effects on 5-hmC content and cell proliferation. Results: We demonstrated significantly higher 5-hmC levels in the genomic DNA of leiomyoma tissue compared to normal myometrial tissue. The increase in 5-hmC levels was associated with the up-regulation of TET1 or TET3 mRNA and protein expression in leiomyoma tissue. TET1 or TET3 knockdown significantly reduced 5-hmC levels in leiomyoma cells and decreased cell proliferation. Treatment with 2-hydroxyglutarate, a competitive TET enzyme inhibitor, significantly decreased both 5-hmC content and cell proliferation of leiomyoma cells. Conclusion: An epigenetic imbalance in the 5-hmC content of leiomyoma tissue, caused by up-regulation of the TET1 and TET3 enzymes, might lead to discovery of new therapeutic targets in leiomyoma. PMID:25057885

Risk of Hippocampal Metastases in Small Cell Lung Cancer Patients at Presentation and After Cranial Irradiation: A Safety Profile Study for Hippocampal Sparing During Prophylactic or Therapeutic Cranial Irradiation

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

Kundapur, Vijayananda, E-mail: Vijayananda.kundapur@saskcancer.ca; Ellchuk, Tasha; Ahmed, Shahid

2015-03-15

Purpose: Neurocognitive impairment (NI) in patients with small cell lung cancer (SCLC) after whole brain radiation treatment (WBRT) is a significant cause of morbidity. Hippocampal avoidance (HA) during WBRT may mitigate or prevent NI in such patients. However, this has not been tested in SCLC patients. The estimated risk of metastases in the HA region (HM) in patients with SCLC at diagnosis or after WBRT is unknown. Our study aimed to determine the risk of HM in patients with SCLC and to assess correlated clinical factors. Methods and Materials: Patients with SCLC who experienced brain metastases (BM) at presentation (demore » novo) or after WBRT treated at the Saskatoon Cancer Centre between 2005 and 2012 were studied. Relevant neuroimaging was independently reviewed by a neuroradiologist. HM was defined as metastases within 5 mm of the hippocampus. Logistic regression analysis was performed to assess correlation between various clinical variables and HM. Results: Seventy eligible patients were identified. Of 59 patients presenting with de novo BM, 3 patients (5%, 95% confidence interval [CI]: 0%-10.7%) had HM. Collectively there were 359 (range, 1-33) de novo BM with 3 (0.8%, 95% CI: 0%-1.7%) HM deposits. Twenty patients experienced progression of metastatic disease in the brain after WBRT. Of the 20 patients, only 1 patient (5%, 95% CI: 0%-14.5%) experienced HM. On logistic regression, no factors significantly correlated with HM. Conclusion: The overall incidence of HM before or after WBRT in SCLC patients is low, providing preliminary support for the safety of HA during planned clinical trials of HA-WBRT for SCLC.« less

Growth and body composition of human milk-fed premature infants provided with extra energy and nutrients early after hospital discharge: 1-year follow-up.

PubMed

Aimone, Ashley; Rovet, Joanne; Ward, Wendy; Jefferies, Ann; Campbell, Douglas M; Asztalos, Elizabeth; Feldman, Mark; Vaughan, Jennifer; Westall, Carol; Whyte, Hilary; O'Connor, Deborah L

2009-10-01

Human milk (HM) is the optimal source of nutrition for premature infants; however, it is unclear whether HM alone is sufficient to meet their elevated nutritional requirements early after hospital discharge. We previously reported that premature infants (750-1800 g birth weight) fed HM containing extra nutrients for 12 weeks after discharge had dietary intakes closer to recommended levels and grew more rapidly than those fed HM alone. The objectives of the present article are to examine the impact of this intervention on bone mineralization, body composition, and HM use up to 1 year. Data are also presented on general developmental level at 18-month corrected age (CA). At discharge, predominantly HM-fed infants were randomized to receive for 12 weeks either approximately half of their feedings containing a multinutrient fortifier (intervention, n=19) or all of their feedings as HM alone (control, n=20). Intervention infants remained longer (P<0.001) and had greater whole-body bone mineral content (P=0.02) until 12-month CA compared with controls. Intervention infants born less than or equal to 1250 g continued to have a larger mean head circumference throughout the first year of life (P<0.0001). Human milk feeding (mL.kg(-1).day(-1)) differed between groups at 6- (P=0.035), but not 12-month CA. No statistically significant differences were found between groups in the mental, motor, or behavior rating scale scores of the Bayley II at 18-month CA. Adding a multinutrient fortifier to HM provided to predominantly HM-fed premature infants early after discharge results in sustained differences in weight, length, and whole-body bone mineral content, and in smaller babies, head circumference for the first year of life.

Effectiveness of the 'Hold me Tight' Relationship Enhancement Program in a Self-referred and a Clinician-referred Sample: An Emotionally Focused Couples Therapy-Based Approach.

PubMed

Conradi, Henk Jan; Dingemanse, Pieter; Noordhof, Arjen; Finkenauer, Catrin; Kamphuis, Jan H

2017-09-04

While evidence-based couple therapies are available, only a minority of troubled couples seek help and they often do this too late. To reach more couples earlier, the couple relationship education (CRE) group program "Hold me Tight" (HmT) based on Emotionally Focused Couples Therapy (EFCT) was developed. This study is the first to examine the effectiveness of HmT. Using a three-wave (waiting period, treatment, and follow-up) within-subject design, HmT was delivered to 79 self-referred couples and 50 clinician-referred couples. We applied a comprehensive outcome measure battery. Our main findings were that (1) self-referred couples significantly improved during HmT on all measures, that is relationship satisfaction, security of partner-bond, forgiveness, daily coordination, maintenance behavior, and psychological complaints, with a moderate-to-large mean effect size (d = .63), which was maintained (d = .57) during the 3.5 month follow-up; (2) in clinician-referred couples, who were vulnerable in terms of insecure attachment status and psychopathology, the improvement during HmT was moderate (d = .42), but this was reduced during the 3.5-month follow-up to a small effect (d = .22); (3) emotional functioning (typical HmT target) as well as behavioral functioning (typical Behavioral Couples Therapy-based CRE target) improved during HmT; and (4) individual psychological complaints, although not specifically targeted, were reduced during HmT. These findings suggest that HmT is a promising intervention for enhancement of relationship functioning. Clinical implications are discussed. © 2017 Family Process Institute.

Does LibQUAL+[TM] Account for Student Loyalty to a University College Library?

ERIC Educational Resources Information Center

Helgesen, Oyvind; Nesset, Erik

2011-01-01

Purpose: The purpose of this paper is to find out whether LibQUAL+[TM]can account for student loyalty to the library of an institution of higher education. LibQUAL+[TM] is a marketing tool that is used to measure perceived service quality of libraries, and the present analysis aims at validating this service quality instrument within a more…

Ten Years of LibQual: A Study of Qualitative and Quantitative Survey Results at the University of Mississippi 2001-2010

ERIC Educational Resources Information Center

Greenwood, Judy T.; Watson, Alex P.; Dennis, Melissa

2011-01-01

This article analyzes quantitative adequacy gap scores and coded qualitative comments from LibQual surveys at the University of Mississippi from 2001 to 2010, looking for relationships between library policy changes and LibQual results and any other trends that emerged. Analysis found no relationship between changes in policy and survey results…

Laser-Induced Breakdown Spectroscopy: Capabilities and Applications

DTIC Science & Technology

2010-07-01

substances such as drugs, counterfeit goods, and laundered money . It may even be possible to pinpoint specific manufacturing facilities based on...point detection or standoff mode operation. LIBS used in conjunction with broadband detectors (ultraviolet [ UV ]-visible[VIS]-near-infrared[NIR] spectral...lines in the UV -VIS-NIR spectral range. Although most early LIBS applications involved metal targets, LIBS has recently been applied to a variety

On-Premises Library versus Google-Like Information Gateway Usage Patterns: A LibQUAL+[R] Study

ERIC Educational Resources Information Center

Thompson, Bruce; Kyrillidou, Martha; Cook, Colleen

2007-01-01

Using LibQUAL+[R] data provided by 295,355 of the participants who completed the LibQUAL+[R] survey in 2003, 2004, and 2005, the present study was conducted to address three research questions. First, what differences, if any, have occurred across time in the use by (a) undergraduates, (b) graduate students/postgraduates, and (c) faculty of…

Decrease of 5-hydroxymethylcytosine in rat liver with subchronic exposure to genotoxic carcinogens riddelliine and aristolochic acid.

PubMed

Lian, Christine Guo; Xu, Shuyun; Guo, Weimin; Yan, Jian; Frank, Maximilian Y M; Liu, Robert; Liu, Cynthia; Chen, Ying; Murphy, George F; Chen, Tao

2015-11-01

The level of 5-hydroxymethylcytosine (5-hmC) converted by ten-eleven translocation (TET) family is decreased in cancers. However, whether 5-hmC level is perturbed in early stages of carcinogenesis caused by genotoxic carcinogens is not defined. 5-hmC levels and TET2 expression were measured in liver of rats treated with genotoxic carcinogens, riddelliine, or aristolochic acid. Levels of 5-hmC and TET2 expression decreased in the liver of the carcinogens-treated rats. Loss of 5-hmC correlates well with documented induction of genetic mutations by the carcinogens, suggesting that TET2-mediated 5-hydroxymethylation plays an epigenetic role in early state of carcinogenesis. © 2014 Wiley Periodicals, Inc.

Decrease of 5-Hydroxymethylcytosine in Rat Liver with Subchronic Exposure to Genotoxic Carcinogens Riddelliine and Aristolochic Acid

PubMed Central

Lian, Christine Guo; Xu, Shuyun; Guo, Weimin; Yan, Jian; Frank, Maximilian Y M; Liu, Robert; Liu, Cynthia; Chen, Ying; Murphy, George F.; Chen, Tao

2018-01-01

The level of 5-hydroxymethylcytosine (5-hmC) converted by ten-eleven translocation (TET) family is decreased in cancers. However, whether 5-hmC level is perturbed in early stages of carcinogenesis caused by genotoxic carcinogens is not defined. 5-hmC levels and TET2 expression were measured in liver of rats treated with genotoxic carcinogens, riddelliine, or aristolochic acid. Levels of 5-hmC and TET2 expression decreased in the liver of the carcinogens-treated rats. Loss of 5-hmC correlates well with documented induction of genetic mutations by the carcinogens, suggesting that TET2-mediated 5-hydroxymethylation plays an epigenetic role in early state of carcinogenesis. PMID:25154389

Study on Emission Spectral Lines of Iron, Fe in Laser-Induced Breakdown Spectroscopy (LIBS) on Soil Samples

NASA Astrophysics Data System (ADS)

Idris, Nasrullah; Lahna, Kurnia; Fadhli; Ramli, Muliadi

2017-05-01

In this work, LIBS technique has been used for detection of heavy metal especially iron, Fe in soil sample. As there are a large number of emission spectral lines due to Fe and other constituents in soil, this study is intended to identify emission spectral lines of Fe and finally to find best fit emission spectral lines for carrying out a qualitative and quantitative analysis. LIBS apparatus used in this work consists of a laser system (Neodymium Yttrium Aluminum Garnet, Nd-YAG: Quanta Ray; LAB SERIES; 1,064 nm; 500 mJ; 8 ns) and an optical multichannel analyzer (OMA) system consisting of a spectrograph (McPherson model 2061; 1,000 mm focal length; f/8.6 Czerny- Turner) and an intensified charge coupled device (ICCD) 1024x256 pixels (Andor I*Star). The soil sample was collected from Banda Aceh city, Aceh, Indonesia. For spectral data acquisition, the soil sample has been prepared by a pressing machine in the form of pellet. The laser beam was focused using a high density lens (f=+150 mm) and irradiated on the surface of the pellet for generating luminous plasma under 1 atmosphere of air surrounding. The plasma emission was collected by an optical fiber and then sent to the optical multichannel analyzer (OMA) system for acquisition of the emission spectra. It was found that there are many Fe emission lines both atomic lines (Fe I) and ionic lines (Fe II) appeared in all detection windows in the wavelength regions, ranging from 200 nm to 1000 nm. The emission lines of Fe with strong intensities occurs together with emission lines due to other atoms such as Mg, Ca, and Si. Thus, the identification of emission lines from Fe is complicated by presence of many other lines due to other major and minor elements in soil. Considering the features of the detected emission lines, several emission spectral lines of Fe I (atomic emission line), especially Fe I 404.58 nm occurring at visible range are potential to be good candidate of analytical lines in relation to detection heavy metal pollution, Fe, in soil sample.

Wood and bark of Pinus halepensis as archives of heavy metal pollution in the Mediterranean Region.

PubMed

Rodríguez Martin, José Antonio; Gutiérrez, Carmen; Torrijos, Manuel; Nanos, Nikos

2018-04-18

Natural levels of heavy metals (HM) have increased during the industrial era to the point of posing a serious threat to the environment. The use of tree species to record contamination is a well-known practice. The objective of the study was to compare HM levels under different pollution conditions: a) soil pollution due to mining waste; b) atmospheric pollution due to coal-fired power plant emissions. We report significant HM enrichment in Pinus halepensis tissues. Near a burning power plant, Pb content in a tree wood was 2.5-fold higher that in natural areas (no pollution; NP). In mining areas, Cd content was 25-fold higher than NP. The hypothesis that HM contents in tree rings should register pollution is debatable. HM uptake by pines from soil, detoxification mechanisms and resuspended local soil dust is involved in HM contents in wood and bark. Copyright © 2018 Elsevier Ltd. All rights reserved.

Interfacial Dzyaloshinskii-Moriya Interaction: Effect of 5 d Band Filling and Correlation with Spin Mixing Conductance

NASA Astrophysics Data System (ADS)

Ma, Xin; Yu, Guoqiang; Tang, Chi; Li, Xiang; He, Congli; Shi, Jing; Wang, Kang L.; Li, Xiaoqin

2018-04-01

The Dzyaloshinskii-Moriya interaction (DMI) at the heavy metal (HM) and ferromagnetic metal (FM) interface has been recognized as a key ingredient in spintronic applications. Here we investigate the chemical trend of DMI on the 5 d band filling (5 d3- 5 d10 ) of the HM element in HM/FM (FM =CoFeB ,Co )/MgO multilayer thin films. DMI is quantitatively evaluated by measuring asymmetric spin wave dispersion using Brillouin light scattering. Sign reversal and 20 times modification of the DMI coefficient D have been measured as the 5 d HM element is varied. The chemical trend can be qualitatively understood by considering the 5 d and 3 d bands alignment at the HM/FM interface and the subsequent orbital hybridization around the Fermi level. Furthermore, a correlation is observed between DMI and effective spin mixing conductance at the HM/FM interfaces. Our results provide new insights into the interfacial DMI for designing future spintronic devices.

Genomic distribution and possible functions of DNA hydroxymethylation in the brain.

PubMed

Wen, Lu; Tang, Fuchou

2014-11-01

DNA methylation (5-methylcytosine, 5mC) is involved in many cellular processes and emerges as an important epigenetic player in brain development and memory formation. The recent discovery that 5mC can be oxidized to 5-hydroxymethylcytosine (5hmC) by TET (Ten-Eleven-Translocation) proteins provides novel insights into the dynamic character of 5mC in the brain. The content of 5hmC is remarkably high in the brain, adding further complexity. In this review, we discuss how recent advances have improved our understanding of the possible biological roles of 5hmC and TET proteins in the brain. These advances attribute to various approaches, including the genome-wide approach to map 5hmC in different genomic contexts, the gene knockout/knockdown approach to elucidate the functions of TET proteins and 5hmC, and the biochemical approach to uncover potential 5hmC readers. Copyright © 2014 Elsevier Inc. All rights reserved.

Comparison of multichannel intraluminal impedance-pH monitoring and reflux scintigraphy in pediatric patients with suspected gastroesophageal reflux.

PubMed

Uslu Kızılkan, Nuray; Bozkurt, Murat Fani; Saltık Temizel, Inci Nur; Demir, Hülya; Yüce, Aysel; Caner, Biray; Özen, Hasan

2016-11-21

To evaluate the agreement of multichannel intraluminal impedance-pH monitoring (MII-pHM) and gastroesophageal reflux scintigraphy (GES) for the diagnosis of gastroesophageal reflux disease. Seventy-five consecutive patients with suspected gastroesophageal reflux disease (GERD) underwent 24-h combined MII-pHM recording and one hour radionuclide scintigraphy during the course of the MII-pHM study. Catheters with 6 impedance channels and 1 pH sensor were placed transnasally. Impedance and pH data analysis were performed automatically and manually. For impedance monitoring, reflux was defined as a retrograde 50% drop in impedance, starting distally and propagating retrogradely to at least the next two more proximal measuring channels. Reflux index (RI, percentage of the entire record that esophageal pH is < 4.0) greater than 4.2% for pHM and number of refluxes more than 50 for 24 h for MII were accepted as positive test results. At scintigraphy, 240 frames of 15 seconds duration were acquired in the supine position. Gastroesophageal reflux was defined as at least one reflux episode in the esophagus. After scintigraphic evaluation, impedance-pH recordings and scintigraphic images were evaluated together and agreement between tests were evaluated with Cohen's kappa. Sufficient data was obtained from 60 (80%) patients (34 male, 56.7%) with a mean age of 8.7 ± 3.7 years (range: 2.5-17.3 years; median: 8.5 years). Chronic cough, nausea, regurgitation and vomiting were the most frequent symptoms. The mean time for recording of MII-pHM was 22.8 ± 2.4 h (range: 16-30 h; median: 22.7 h). At least one test was positive in 57 (95%) patients. According to diagnostic criteria, GERD was diagnosed in 34 (57.7%), 44 (73.3%), 47 (78.3%) and 51 (85%) patients by means of pHM, MII, GES and MII-pHM, respectively. The observed percentage agreements/κ values for GES and pHM, GES and MII, GES and MII-pHM, and MII and pHM are 48.3%/-0.118; 61.7%/-0.042; 73.3%/0.116 and 60%/0.147, respectively. There was no or slight agreement between GES and pHM alone, MII alone or MII-pHM. pH monitoring alone missed 17 patients compared to combined MII-pHM. The addition of MII to pH monitoring increased the diagnosis rate by 50%. No or slight agreement was found among pH monitoring, MII monitoring, MII-pH monitoring and GES for the diagnosis of gastroesophageal reflux disease.

Comparison of multichannel intraluminal impedance-pH monitoring and reflux scintigraphy in pediatric patients with suspected gastroesophageal reflux

PubMed Central

Uslu Kızılkan, Nuray; Bozkurt, Murat Fani; Saltık Temizel, Inci Nur; Demir, Hülya; Yüce, Aysel; Caner, Biray; Özen, Hasan

2016-01-01

AIM To evaluate the agreement of multichannel intraluminal impedance-pH monitoring (MII-pHM) and gastroesophageal reflux scintigraphy (GES) for the diagnosis of gastroesophageal reflux disease. METHODS Seventy-five consecutive patients with suspected gastroesophageal reflux disease (GERD) underwent 24-h combined MII-pHM recording and one hour radionuclide scintigraphy during the course of the MII-pHM study. Catheters with 6 impedance channels and 1 pH sensor were placed transnasally. Impedance and pH data analysis were performed automatically and manually. For impedance monitoring, reflux was defined as a retrograde 50% drop in impedance, starting distally and propagating retrogradely to at least the next two more proximal measuring channels. Reflux index (RI, percentage of the entire record that esophageal pH is < 4.0) greater than 4.2% for pHM and number of refluxes more than 50 for 24 h for MII were accepted as positive test results. At scintigraphy, 240 frames of 15 seconds duration were acquired in the supine position. Gastroesophageal reflux was defined as at least one reflux episode in the esophagus. After scintigraphic evaluation, impedance-pH recordings and scintigraphic images were evaluated together and agreement between tests were evaluated with Cohen’s kappa. RESULTS Sufficient data was obtained from 60 (80%) patients (34 male, 56.7%) with a mean age of 8.7 ± 3.7 years (range: 2.5-17.3 years; median: 8.5 years). Chronic cough, nausea, regurgitation and vomiting were the most frequent symptoms. The mean time for recording of MII-pHM was 22.8 ± 2.4 h (range: 16-30 h; median: 22.7 h). At least one test was positive in 57 (95%) patients. According to diagnostic criteria, GERD was diagnosed in 34 (57.7%), 44 (73.3%), 47 (78.3%) and 51 (85%) patients by means of pHM, MII, GES and MII-pHM, respectively. The observed percentage agreements/κ values for GES and pHM, GES and MII, GES and MII-pHM, and MII and pHM are 48.3%/-0.118; 61.7%/-0.042; 73.3%/0.116 and 60%/0.147, respectively. There was no or slight agreement between GES and pHM alone, MII alone or MII-pHM. pH monitoring alone missed 17 patients compared to combined MII-pHM. The addition of MII to pH monitoring increased the diagnosis rate by 50%. CONCLUSION No or slight agreement was found among pH monitoring, MII monitoring, MII-pH monitoring and GES for the diagnosis of gastroesophageal reflux disease. PMID:27920480

Epigenetic mechanisms involved in the effects of stress exposure: focus on 5-hydroxymethylcytosine.

PubMed

Hack, Laura M; Dick, Alec L W; Provençal, Nadine

2016-08-01

5-hydroxymethylcytosine (5hmC) is a recently re-discovered transient intermediate in the active demethylation pathway that also appears to play an independent role in modulating gene function. Epigenetic marks, particularly 5-methylcytosine, have been widely studied in relation to stress-related disorders given the long-lasting effect that stress has on these marks. 5hmC is a good candidate for involvement in the etiology of these disorders given its elevated concentration in mammalian neurons, its dynamic regulation during development of the central nervous system, and its high variability among individuals. Although we are unaware of any studies published to date examining 5 hmC profiles in human subjects who have developed a psychiatric disorder after a life stressor, there is emerging evidence from the animal literature that 5hmC profiles are altered in the context of fear-conditioning paradigms and stress exposure, suggesting a possible role for 5hmC in the biological underpinnings of stress-related disorders. In this review, the authors examine the available approaches for profiling 5hmC and describe their advantages and disadvantages as well as discuss the studies published thus far investigating 5hmC in the context of fear-related learning and stress exposure in animals. The authors also highlight the global versus locus-specific regulation of 5hmC in these studies. Finally, the limitations of the current studies and their implications are discussed.

[An emergy-ecological footprint model based evaluation of ecological security at the old industrial area in Northeast China: A case study of Liaoning Province.

PubMed

Yang, Qing; Lu, Cheng Peng; Zhou, Feng; Geng, Yong; Jing, Hong Shuang; Ren, Wan Xia; Xue, Bing

2016-05-01

Based on the integrated model of emergy-ecological footprint approaches, the ecological security of Liaoning Province, a typical case for the old industrial area, was quantitatively evaluated from 2003 to 2012, followed by a scenario analysis on the development trend of the ecological secu-rity by employing the gray kinetic model. The results showed that, from 2003 to 2012, the value of emergy ecological-capacity per capita in Liaoning Province decreased from 3.13 hm 2 to 3.07 hm 2 , while the emergy-ecological footprint increased from 13.88 hm 2 to 21.96 hm 2 , which indicated that the ecological deficit existed in Liaoning Province and the situation was getting worse. The ecological pressure index increased from 4.43 to 7.16 during the studied period, and the alert level of ecological security changed from light to middle level. According to the development trend, the emergy ecological capacity per capita during 2013-2022 would correspondingly decrease from 3.04 hm 2 to 2.98 hm 2 , while the emergy ecological footprint would increase from 22.72 hm 2 to 35.87 hm 2 , the ecological pressure index would increase from 7.46 to 12.04, and the ecological deficit would keep increasing and the ecological security level would slide into slightly unsafe condition. The alert level of ecological security would turn to be middle or serious, suggesting the problems in ecological safety needed to be solved urgently.

5-Hydroxymethylcytosine-mediated alteration of transposon activity associated with the exposure to adverse in utero environments in human

PubMed Central

Sun, Miao; Song, Mingxi M.; Wei, Bin; Gao, Qinqin; Li, Lingjun; Yao, Bing; Chen, Li; Lin, Li; Dai, Qing; Zhou, Xiuwen; Tao, Jianying; Chen, Jie; He, Chuan; Jin, Peng; Xu, Zhice

2016-01-01

Preeclampsia and gestational diabetes mellitus (GDM) are the most common clinical conditions in pregnancy that could result in adverse in utero environments. Fetal exposure to poor environments may raise the long-term risk of postnatal disorders, while epigenetic modifications could be involved. Recent research has implicated involvement of 5-hydroxymethylcytosine (5hmC), a DNA base derived from 5-methylcytosine, via oxidation by ten–eleven translocation (TET) enzymes, in DNA methylation-related plasticity. Here, we show that the TET2 expression and 5hmC abundance are significantly altered in the umbilical veins of GDM and preeclampsia. Genome-wide profiling of 5hmC revealed its specific reduction on intragenic regions from both GDM and preeclampsia compared to healthy controls. Gene Ontology analysis using loci bearing unique GDM- and preeclampsia-specific loss-of-5hmC indicated its impact on several critical biological pathways. Interestingly, the substantial alteration of 5hmC on several transposons and repetitive elements led to their differential expression. The alteration of TET expression, 5hmC levels and 5hmC-mediated transposon activity was further confirmed using established hypoxia cell culture model, which could be rescued by vitamin C, a known activator of TET proteins. Together, these results suggest that adverse pregnancy environments could influence 5hmC-mediated epigenetic profile and contribute to abnormal development of fetal vascular systems that may lead to postnatal diseases. PMID:27005421

A Simple Device for Lens-to-Sample Distance Adjustment in Laser-Induced Breakdown Spectroscopy (LIBS).

PubMed

Cortez, Juliana; Farias Filho, Benedito B; Fontes, Laiane M; Pasquini, Celio; Raimundo, Ivo M; Pimentel, Maria Fernanda; de Souza Lins Borba, Flávia

2017-04-01

A simple device based on two commercial laser pointers is described to assist in the analysis of samples that present uneven surfaces and/or irregular shapes using laser-induced breakdown spectroscopy (LIBS). The device allows for easy positioning of the sample surface at a reproducible distance from the focusing lens that conveys the laser pulse to generate the micro-plasma in a LIBS system, with reproducibility better than ±0.2 mm. In this way, fluctuations in the fluence (J cm -2 ) are minimized and the LIBS analytical signals can be obtained with a better precision even when samples with irregular surfaces are probed.

[Progress in the application of laser ablation ICP-MS to surface microanalysis in material science].

PubMed

Zhang, Yong; Jia, Yun-hai; Chen, Ji-wen; Shen, Xue-jing; Liu, Ying; Zhao, Leiz; Li, Dong-ling; Hang, Peng-cheng; Zhao, Zhen; Fan, Wan-lun; Wang, Hai-zhou

2014-08-01

In the present paper, apparatus and theory of surface analysis is introduced, and the progress in the application of laser ablation ICP-MS to microanalysis in ferrous, nonferrous and semiconductor field is reviewed in detail. Compared with traditional surface analytical tools, such as SEM/EDS (scanning electron microscopy/energy dispersive spectrum), EPMA (electron probe microanalysis analysis), AES (auger energy spectrum), etc. the advantage is little or no sample preparation, adjustable spatial resolution according to analytical demand, multi-element analysis and high sensitivity. It is now a powerful complementary method to traditional surface analytical tool. With the development of LA-ICP-MS technology maturing, more and more analytical workers will use this powerful tool in the future, and LA-ICP-MS will be a super star in elemental analysis field just like LIBS (Laser-induced breakdown spectroscopy).

Hierarchically Nanostructured Transition Metal Oxides for Lithium‐Ion Batteries

PubMed Central

Zheng, Mingbo; Tang, Hao; Li, Lulu; Hu, Qin; Zhang, Li; Xue, Huaiguo

2018-01-01

Abstract Lithium‐ion batteries (LIBs) have been widely used in the field of portable electric devices because of their high energy density and long cycling life. To further improve the performance of LIBs, it is of great importance to develop new electrode materials. Various transition metal oxides (TMOs) have been extensively investigated as electrode materials for LIBs. According to the reaction mechanism, there are mainly two kinds of TMOs, one is based on conversion reaction and the other is based on intercalation/deintercalation reaction. Recently, hierarchically nanostructured TMOs have become a hot research area in the field of LIBs. Hierarchical architecture can provide numerous accessible electroactive sites for redox reactions, shorten the diffusion distance of Li‐ion during the reaction, and accommodate volume expansion during cycling. With rapid research progress in this field, a timely account of this advanced technology is highly necessary. Here, the research progress on the synthesis methods, morphological characteristics, and electrochemical performances of hierarchically nanostructured TMOs for LIBs is summarized and discussed. Some relevant prospects are also proposed. PMID:29593962

Elemental and mineralogical imaging of a weathered limestone rock by double-pulse micro-Laser-Induced Breakdown Spectroscopy

NASA Astrophysics Data System (ADS)

Senesi, Giorgio S.; Campanella, Beatrice; Grifoni, Emanuela; Legnaioli, Stefano; Lorenzetti, Giulia; Pagnotta, Stefano; Poggialini, Francesco; Palleschi, Vincenzo; De Pascale, Olga

2018-05-01

The present work aims to evaluate the alteration conditions of historical limestone rocks exposed to urban environment using the Laser-Induced Breakdown Spectroscopy (LIBS) technique. The approach proposed is based on the microscale three dimensional (3D) compositional imaging of the sample through double-pulse micro-Laser-Induced Breakdown Spectroscopy (DP-μLIBS) in conjunction with optical microscopy. DP-μLIBS allows to perform a quick and detailed in-depth analysis of the composition of the weathered artifact by creating a 'virtual thin section' (VTS) of the sample which can estimate the extent of the alteration processes occurred at the limestone surface. The DP-μLIBS analysis of these thin sections showed a reduction with depth of the elements (mainly Fe, Si and Na) originating from atmospheric dust, particulate deposition and the surrounding environment (due to the proximity of the sea), whereas, the LIBS signal of Ca increased in intensity from the black crust to the limestone underneath.

Determination of elemental composition of coffee using UV-pulsed laser induced breakdown spectroscopy

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

Gondal, M. A., E-mail: magondal@kfupm.edu.sa; Baig, Umair; Dastageer, M. A.

A detection system based on laser induced breakdown spectroscopy (LIBS) was built using 266 nm wavelength pulsed laser from the fourth harmonic of Nd:YAG laser, 500 mm spectrograph and gated ICCD camera with built-in delay generator. The LIBS system was used to study the elemental composition in coffee available in the local market of Saudi Arabia for the detection of elements in coffee samples. The LIBS spectrum of coffee sample revealed the presence magnesium, calcium, aluminum, copper, sodium, barium, bromine, cobalt, chromium, cerium manganese and molybdenum. Atomic transition line of sodium is used to study the parametric dependence of LIBSmore » signal. The study of the dependence of LIBS signal on the laser pulse energy is proven to be linear and the dependence of LIBS signal on the time delay between the excitation and data acquisition showed a typical increase, a peak value and a decrease with the optimum excitation – acquisition delay at 400 ns.« less

Determination of elemental composition of shale rocks by laser induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Sanghapi, Hervé K.; Jain, Jinesh; Bol'shakov, Alexander; Lopano, Christina; McIntyre, Dustin; Russo, Richard

2016-08-01

In this study laser induced breakdown spectroscopy (LIBS) is used for elemental characterization of outcrop samples from the Marcellus Shale. Powdered samples were pressed to form pellets and used for LIBS analysis. Partial least squares regression (PLS-R) and univariate calibration curves were used for quantification of analytes. The matrix effect is substantially reduced using the partial least squares calibration method. Predicted results with LIBS are compared to ICP-OES results for Si, Al, Ti, Mg, and Ca. As for C, its results are compared to those obtained by a carbon analyzer. Relative errors of the LIBS measurements are in the range of 1.7 to 12.6%. The limits of detection (LODs) obtained for Si, Al, Ti, Mg and Ca are 60.9, 33.0, 15.6, 4.2 and 0.03 ppm, respectively. An LOD of 0.4 wt.% was obtained for carbon. This study shows that the LIBS method can provide a rapid analysis of shale samples and can potentially benefit depleted gas shale carbon storage research.

Flexible phosphorus doped carbon nanosheets/nanofibers: Electrospun preparation and enhanced Li-storage properties as free-standing anodes for lithium ion batteries

NASA Astrophysics Data System (ADS)

Li, Desheng; Wang, Dongya; Rui, Kun; Ma, Zhongyuan; Xie, Ling; Liu, Jinhua; Zhang, Yu; Chen, Runfeng; Yan, Yan; Lin, Huijuan; Xie, Xiaoji; Zhu, Jixin; Huang, Wei

2018-04-01

The emerging wearable and foldable electronic devices drive the development of flexible lithium ion batteries (LIBs). Carbon materials are considered as one of the most promising electrode materials for LIBs due to their light weight, low cost and good structural stability against repeated deformations. However, the specific capacity, rate capability and long-term cycling performance still need to be improved for their applications in next-generation LIBs. Herein, we report a facile approach for immobilizing phosphorus into a large-area carbon nanosheets/nanofibers interwoven free-standing paper for LIBs. As an anode material for LIBs, it shows high reversible capacity of 1100 mAh g-1 at a current density of 200 mA g-1, excellent rate capabilities (e.g., 200 mAh g-1 at 20,000 mA g-1). Even at a high current density of 1000 mA g-1, it still maintains a superior specific capacity of 607 mAh g-1 without obvious decay.

Assessment of statistical uncertainty in the quantitative analysis of solid samples in motion using laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Cabalín, L. M.; González, A.; Ruiz, J.; Laserna, J. J.

2010-08-01

Statistical uncertainty in the quantitative analysis of solid samples in motion by laser-induced breakdown spectroscopy (LIBS) has been assessed. For this purpose, a LIBS demonstrator was designed and constructed in our laboratory. The LIBS system consisted of a laboratory-scale conveyor belt, a compact optical module and a Nd:YAG laser operating at 532 nm. The speed of the conveyor belt was variable and could be adjusted up to a maximum speed of 2 m s - 1 . Statistical uncertainty in the analytical measurements was estimated in terms of precision (reproducibility and repeatability) and accuracy. The results obtained by LIBS on shredded scrap samples under real conditions have demonstrated that the analytical precision and accuracy of LIBS is dependent on the sample geometry, position on the conveyor belt and surface cleanliness. Flat, relatively clean scrap samples exhibited acceptable reproducibility and repeatability; by contrast, samples with an irregular shape or a dirty surface exhibited a poor relative standard deviation.

Hierarchically Nanostructured Transition Metal Oxides for Lithium-Ion Batteries.

PubMed

Zheng, Mingbo; Tang, Hao; Li, Lulu; Hu, Qin; Zhang, Li; Xue, Huaiguo; Pang, Huan

2018-03-01

Lithium-ion batteries (LIBs) have been widely used in the field of portable electric devices because of their high energy density and long cycling life. To further improve the performance of LIBs, it is of great importance to develop new electrode materials. Various transition metal oxides (TMOs) have been extensively investigated as electrode materials for LIBs. According to the reaction mechanism, there are mainly two kinds of TMOs, one is based on conversion reaction and the other is based on intercalation/deintercalation reaction. Recently, hierarchically nanostructured TMOs have become a hot research area in the field of LIBs. Hierarchical architecture can provide numerous accessible electroactive sites for redox reactions, shorten the diffusion distance of Li-ion during the reaction, and accommodate volume expansion during cycling. With rapid research progress in this field, a timely account of this advanced technology is highly necessary. Here, the research progress on the synthesis methods, morphological characteristics, and electrochemical performances of hierarchically nanostructured TMOs for LIBs is summarized and discussed. Some relevant prospects are also proposed.

Application of a compact diode pumped solid-state laser source for quantitative laser-induced breakdown spectroscopy analysis of steel

NASA Astrophysics Data System (ADS)

Tortschanoff, Andreas; Baumgart, Marcus; Kroupa, Gerhard

2017-12-01

Laser-induced breakdown spectroscopy (LIBS) technology holds the potential for onsite real-time measurements of steel products. However, for a mobile and robust LIBS measurement system, an adequate small and ruggedized laser source is a key requirement. In this contribution, we present tests with our compact high-power laser source, which, initially, was developed for ignition applications. The CTR HiPoLas® laser is a robust diode pumped solid-state laser with a passive Q-switch with dimensions of less than 10 cm3. The laser generates 2.5-ns pulses with 30 mJ at a maximum continuous repetition rate of about 30 Hz. Feasibility of LIBS experiments with the laser source was experimentally verified with steel samples. The results show that the laser with its current optical output parameters is very well-suited for LIBS measurements. We believe that the miniaturized laser presented here will enable very compact and robust portable high-performance LIBS systems.

Quantitative analysis of titanium concentration using calibration-free laser-induced breakdown spectroscopy (LIBS)

NASA Astrophysics Data System (ADS)

Zaitun; Prasetyo, S.; Suliyanti, M. M.; Isnaeni; Herbani, Y.

2018-03-01

Laser-induced breakdown spectroscopy (LIBS) can be used for quantitative and qualitative analysis. Calibration-free LIBS (CF-LIBS) is a method to quantitatively analyze concentration of elements in a sample in local thermodynamic equilibrium conditions without using available matrix-matched calibration. In this study, we apply CF-LIBS for quantitative analysis of Ti in TiO2 sample. TiO2 powder sample was mixed with polyvinyl alcohol and formed into pellets. An Nd:YAG pulsed laser at a wavelength of 1064 nm was focused onto the sample to generate plasma. The spectrum of plasma was recorded using spectrophotometer then compared to NIST spectral line to determine energy levels and other parameters. The value of plasma temperature obtained using Boltzmann plot is 8127.29 K and electron density from calculation is 2.49×1016 cm-3. Finally, the concentration of Ti in TiO2 sample from this study is 97% that is in proximity with the sample certificate.

Multivariate analysis of remote LIBS spectra using partial least squares, principal component analysis, and related techniques

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

Clegg, Samuel M; Barefield, James E; Wiens, Roger C

2008-01-01

Quantitative analysis with LIBS traditionally employs calibration curves that are complicated by the chemical matrix effects. These chemical matrix effects influence the LIBS plasma and the ratio of elemental composition to elemental emission line intensity. Consequently, LIBS calibration typically requires a priori knowledge of the unknown, in order for a series of calibration standards similar to the unknown to be employed. In this paper, three new Multivariate Analysis (MV A) techniques are employed to analyze the LIBS spectra of 18 disparate igneous and highly-metamorphosed rock samples. Partial Least Squares (PLS) analysis is used to generate a calibration model from whichmore » unknown samples can be analyzed. Principal Components Analysis (PCA) and Soft Independent Modeling of Class Analogy (SIMCA) are employed to generate a model and predict the rock type of the samples. These MV A techniques appear to exploit the matrix effects associated with the chemistries of these 18 samples.« less

Elemental content of enamel and dentin after bleaching of teeth (a comparative study between laser-induced breakdown spectroscopy and x-ray photoelectron spectroscopy)

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

Imam, H.; Ahmed, Doaa; Eldakrouri, Ashraf

2013-06-21

The elemental content of the superficial and inner enamel as well as that of dentin was analyzed using laser-induced breakdown spectroscopy (LIBS) and x-ray photoelectron spectroscopy (XPS) of bleached and unbleached tooth specimens. It is thus clear from the spectral analysis using both the LIBS and XPS technique that elemental changes (though insignificant within the scopes of this study) of variable intensities do occur on the surface of the enamel and extend deeper to reach dentin. The results of the LIBS revealed a slight reduction in the calcium levels in the bleached compared to the control specimens in all themore » different bleaching groups and in both enamel and dentin. The good correlation found between the LIBS and XPS results demonstrates the possibility of LIBS technique for detection of minor loss in calcium and phosphorus in enamel and dentin.« less

Nanocarbons for Battery Applications in China

DTIC Science & Technology

2015-04-29

Lithium - Ion Batteries (LIBs)   Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of...Conductive Additives in Lithium - Ion Batteries (LIBs)   3.3.3   As Composite Cathodes in Lithium -Sulfur (Li-S) Batteries   3.3.6.1   CNTs...composite electrode materials and conductive additives in lithium - ion batteries (LIBs) and composite cathodes in novel lithium -sulfur (Li-S) and

Thermo-electrochemical analysis of lithium ion batteries for space applications using Thermal Desktop

NASA Astrophysics Data System (ADS)

Walker, W.; Ardebili, H.

2014-12-01

Lithium-ion batteries (LIBs) are replacing the Nickel-Hydrogen batteries used on the International Space Station (ISS). Knowing that LIB efficiency and survivability are greatly influenced by temperature, this study focuses on the thermo-electrochemical analysis of LIBs in space orbit. Current finite element modeling software allows for advanced simulation of the thermo-electrochemical processes; however the heat transfer simulation capabilities of said software suites do not allow for the extreme complexities of orbital-space environments like those experienced by the ISS. In this study, we have coupled the existing thermo-electrochemical models representing heat generation in LIBs during discharge cycles with specialized orbital-thermal software, Thermal Desktop (TD). Our model's parameters were obtained from a previous thermo-electrochemical model of a 185 Amp-Hour (Ah) LIB with 1-3 C (C) discharge cycles for both forced and natural convection environments at 300 K. Our TD model successfully simulates the temperature vs. depth-of-discharge (DOD) profiles and temperature ranges for all discharge and convection variations with minimal deviation through the programming of FORTRAN logic representing each variable as a function of relationship to DOD. Multiple parametrics were considered in a second and third set of cases whose results display vital data in advancing our understanding of accurate thermal modeling of LIBs.

Medical Applications of Laser Induced Breakdown Spectroscopy

NASA Astrophysics Data System (ADS)

Pathak, A. K.; Rai, N. K.; Singh, Ankita; Rai, A. K.; Rai, Pradeep K.; Rai, Pramod K.

2014-11-01

Sedentary lifestyle of human beings has resulted in various diseases and in turn we require a potential tool that can be used to address various issues related to human health. Laser Induced Breakdown Spectroscopy (LIBS) is one such potential optical analytical tool that has become quite popular because of its distinctive features that include applicability to any type/phase of samples with almost no sample preparation. Several reports are available that discusses the capabilities of LIBS, suitable for various applications in different branches of science which cannot be addressed by traditional analytical methods but only few reports are available for the medical applications of LIBS. In the present work, LIBS has been implemented to understand the role of various elements in the formation of gallstones (formed under the empyema and mucocele state of gallbladder) samples along with patient history that were collected from Purvancal region of Uttar Pradesh, India. The occurrence statistics of gallstones under the present study reveal higher occurrence of gallstones in female patients. The gallstone occurrence was found more prevalent for those male patients who were having the habit of either tobacco chewing, smoking or drinking alcohols. This work further reports in-situ LIBS study of deciduous tooth and in-vivo LIBS study of human nail.

Laser-Induced Breakdown Spectroscopy Coupled with Multivariate Chemometrics for Variety Discrimination of Soil

PubMed Central

Yu, Ke-Qiang; Zhao, Yan-Ru; Liu, Fei; He, Yong

2016-01-01

The aim of this work was to analyze the variety of soil by laser-induced breakdown spectroscopy (LIBS) coupled with chemometrics methods. 6 certified reference materials (CRMs) of soil samples were selected and their LIBS spectra were captured. Characteristic emission lines of main elements were identified based on the LIBS curves and corresponding contents. From the identified emission lines, LIBS spectra in 7 lines with high signal-to-noise ratio (SNR) were chosen for further analysis. Principal component analysis (PCA) was carried out using the LIBS spectra at 7 selected lines and an obvious cluster of 6 soils was observed. Soft independent modeling of class analogy (SIMCA) and least-squares support vector machine (LS-SVM) were introduced to establish discriminant models for classifying the 6 types of soils, and they offered the correct discrimination rates of 90% and 100%, respectively. Receiver operating characteristic (ROC) curve was used to evaluate the performance of models and the results demonstrated that the LS-SVM model was promising. Lastly, 8 types of soils from different places were gathered to conduct the same experiments for verifying the selected 7 emission lines and LS-SVM model. The research revealed that LIBS technology coupled with chemometrics could conduct the variety discrimination of soil. PMID:27279284

Classification of alloys using laser induced breakdown spectroscopy with principle component analysis

NASA Astrophysics Data System (ADS)

Syuhada Mangsor, Aneez; Haider Rizvi, Zuhaib; Chaudhary, Kashif; Safwan Aziz, Muhammad

2018-05-01

The study of atomic spectroscopy has contributed to a wide range of scientific applications. In principle, laser induced breakdown spectroscopy (LIBS) method has been used to analyse various types of matter regardless of its physical state, either it is solid, liquid or gas because all elements emit light of characteristic frequencies when it is excited to sufficiently high energy. The aim of this work was to analyse the signature spectrums of each element contained in three different types of samples. Metal alloys of Aluminium, Titanium and Brass with the purities of 75%, 80%, 85%, 90% and 95% were used as the manipulated variable and their LIBS spectra were recorded. The characteristic emission lines of main elements were identified from the spectra as well as its corresponding contents. Principal component analysis (PCA) was carried out using the data from LIBS spectra. Three obvious clusters were observed in 3-dimensional PCA plot which corresponding to the different group of alloys. Findings from this study showed that LIBS technology with the help of principle component analysis could conduct the variety discrimination of alloys demonstrating the capability of LIBS-PCA method in field of spectro-analysis. Thus, LIBS-PCA method is believed to be an effective method for classifying alloys with different percentage of purifications, which was high-cost and time-consuming before.

Tandem Laser Induced Breakdown Spectroscopy (LIBS), Laser Ablation Inductively Coupled Plasma Mass Spectroscopy (LA-ICP-MS) and/or Laser Ablation Inductively Coupled Plasma Optical Emission Spectroscopy (LA-ICP-OES) for the analysis of samples of geological interest

NASA Astrophysics Data System (ADS)

Oropeza, D.

2016-12-01

A highly innovative laser ablation sampling instrument (J200 Tandem LA - LIBS) that combines the capabilities and analytical benefits of LIBS, LA-ICP-MS and LA-ICP-OES was used for micrometer-scale, spatially-resolved, elemental analysis of a wide variety of samples of geological interest. Data collected using ablation systems consisted of nanosecond (Nd:YAG operated 266nm) and femtosecond lasers (1030 and 343nm). An ICCD LIBS detector and Quadrupole based mass spectrometer were selected for LIBS and ICP-MS detection, respectively. This tandem instrument allows simultaneous determination of major and minor elements (for example, Si, Ca, Na, and Al, and trace elements such as Li, Ce, Cr, Sr, Y, Zn, Zr among others). The research also focused on elemental mapping and calibration strategies, specifically the use of emission and mass spectra for multivariate data analysis. Partial Least Square Regression (PLSR) is shown to minimize and compensate for matrix effects in the emission and mass spectra improving quantitative analysis by LIBS and LA-ICP-MS, respectively. The study provides a benchmark to evaluate analytical results for more complex geological sample matrices.

Monitoring of Cr, Cu, Pb, V and Zn in polluted soils by laser induced breakdown spectroscopy (LIBS).

PubMed

Dell'Aglio, Marcella; Gaudiuso, Rosalba; Senesi, Giorgio S; De Giacomo, Alessandro; Zaccone, Claudio; Miano, Teodoro M; De Pascale, Olga

2011-05-01

Laser Induced Breakdown Spectroscopy (LIBS) is a fast and multi-elemental analytical technique particularly suitable for the qualitative and quantitative analysis of heavy metals in solid samples, including environmental ones. Although LIBS is often recognised in the literature as a well-established analytical technique, results about quantitative analysis of elements in chemically complex matrices such as soils are quite contrasting. In this work, soil samples of various origins have been analyzed by LIBS and data compared to those obtained by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The emission intensities of one selected line for each of the five analytes (i.e., Cr, Cu, Pb, V, and Zn) were normalized to the background signal, and plotted as a function of the concentration values previously determined by ICP-OES. Data showed a good linearity for all calibration lines drawn, and the correlation between ICP-OES and LIBS was confirmed by the satisfactory agreement obtained between the corresponding values. Consequently, LIBS method can be used at least for metal monitoring in soils. In this respect, a simple method for the estimation of the soil pollution degree by heavy metals, based on the determination of an anthropogenic index, was proposed and determined for Cr and Zn.

Depth-resolved multilayer pigment identification in paintings: combined use of laser-induced breakdown spectroscopy (LIBS) and optical coherence tomography (OCT).

PubMed

Kaszewska, Ewa A; Sylwestrzak, Marcin; Marczak, Jan; Skrzeczanowski, Wojciech; Iwanicka, Magdalena; Szmit-Naud, Elżbieta; Anglos, Demetrios; Targowski, Piotr

2013-08-01

A detailed feasibility study on the combined use of laser-induced breakdown spectroscopy with optical coherence tomography (LIBS/OCT), aiming at a realistic depth-resolved elemental analysis of multilayer stratigraphies in paintings, is presented. Merging a high spectral resolution LIBS system with a high spatial resolution spectral OCT instrument significantly enhances the quality and accuracy of stratigraphic analysis. First, OCT mapping is employed prior to LIBS analysis in order to assist the selection of specific areas of interest on the painting surface to be examined in detail. Then, intertwined with LIBS, the OCT instrument is used as a precise profilometer for the online determination of the depth of the ablation crater formed by individual laser pulses during LIBS depth-profile analysis. This approach is novel and enables (i) the precise in-depth scaling of elemental concentration profiles, and (ii) the recognition of layer boundaries by estimating the corresponding differences in material ablation rate. Additionally, the latter is supported, within the transparency of the object, by analysis of the OCT cross-sectional views. The potential of this method is illustrated by presenting results on the detailed analysis of the structure of an historic painting on canvas performed to aid planned restoration of the artwork.

Wavelength comparison for laser induced breakdown spectroscopy caries detection

NASA Astrophysics Data System (ADS)

Amaral, Marcello M.; Raele, Marcus P.; Ana, Patrícia A.; Núñez, Sílvia C.; Zamataro, Claudia B.; Zezell, Denise M.

2018-02-01

Laser Induced Breakdown Spectroscopy (LIBS) is a technique capable to perform elemental analyses of a variety of samples, independent of matter state. Other spectroscopy techniques may require a destructive and time-consuming sample preparation. On the other hand, LIBS is a less destructive technique with no (or considerably less) sample preparation, using a relatively simple experimental setup. LIBS also provides a multielement analysis into one single spectrum acquisition, applying a Nd:YAG short-pulsed laser to ensure the stoichiometry between the sample and the generated plasma. LIBS have been applied on the study of carious lesions using a Nd:YAG into its fundamental emission at 1064 nm. It was shown that ratio of P/Ca and Zn/Ca can be used to monitor the cariogenic process. Another minor elements, e.g. C and Cu, associated with bacteria biofilm were also measured with the Nd:YAG laser. The fundamental wavelength emission (1064 nm) of Nd:YAG is coincident with a hydroxyapatite transmission window and it may affect the result. In order to address this issue a study used the second harmonic of the Nd:YAG laser at 532 nm. It was show that it is also possible perform LIBS on carious lesion using the Nd:YAG at 532 nm. However, there is not a work direct comparing the LIBS at 532 nm and 1064 nm for carious lesion detection. So, the aim of this work was to investigate the influence of laser wavelength on the LIBS performance for carious lesion detection. In both cases the carious lesion was detected with the advantage of no interference with hydroxyapatite at 532 nm.

Stark width and shift for electron number density diagnostics of low temperature plasma: Application to silicon Laser Induced Breakdown Spectroscopy

NASA Astrophysics Data System (ADS)

Ivković, M.; Konjević, N.

2017-05-01

In this work we summarize, analyze and critically evaluate experimental procedures and results of LIBS electron number density plasma characterization using as examples Stark broadened Si I and Si II line profiles. Selected publications are covering the time period from very beginning of silicon LIBS studies until the end of the year 2015. To perform the analysis of experimental LIBS data, the testing of available semiclassical theoretical Stark broadening parameters for Si I and Si II lines was accomplished first. This is followed by the description of experimental setups, results and details of experimental procedure relevant for the line shape analysis of spectral lines used for plasma characterization. Although most of results and conclusions of this analysis are related to the application of silicon lines for LIBS characterization they are of general importance and may be applied to other elements and different low-temperature plasma sources. The analysis of experimental procedures used for LIBS diagnostics from emission profiles of non-hydrogenic spectral lines is carried out in the following order: the influence of laser ablation and crater formation, spatial and temporal plasma observation, line self-absorption and experimental profile deconvolution, the contribution of ion broadening in comparison with electron impacts contributions to the line width in case of neutral atom line and some other aspects of line shape analysis are considered. The application of Stark shift for LIBS diagnostics is demonstrated and discussed. Finally, the recommendations for an improvement of experimental procedures for LIBS electron number density plasma characterization are offered.

Characterization and forensic analysis of soil samples using laser-induced breakdown spectroscopy (LIBS).

PubMed

Jantzi, Sarah C; Almirall, José R

2011-07-01

A method for the quantitative elemental analysis of surface soil samples using laser-induced breakdown spectroscopy (LIBS) was developed and applied to the analysis of bulk soil samples for discrimination between specimens. The use of a 266 nm laser for LIBS analysis is reported for the first time in forensic soil analysis. Optimization of the LIBS method is discussed, and the results compared favorably to a laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) method previously developed. Precision for both methods was <10% for most elements. LIBS limits of detection were <33 ppm and bias <40% for most elements. In a proof of principle study, the LIBS method successfully discriminated samples from two different sites in Dade County, FL. Analysis of variance, Tukey's post hoc test and Student's t test resulted in 100% discrimination with no type I or type II errors. Principal components analysis (PCA) resulted in clear groupings of the two sites. A correct classification rate of 99.4% was obtained with linear discriminant analysis using leave-one-out validation. Similar results were obtained when the same samples were analyzed by LA-ICP-MS, showing that LIBS can provide similar information to LA-ICP-MS. In a forensic sampling/spatial heterogeneity study, the variation between sites, between sub-plots, between samples and within samples was examined on three similar Dade sites. The closer the sampling locations, the closer the grouping on a PCA plot and the higher the misclassification rate. These results underscore the importance of careful sampling for geographic site characterization.

[Quantitative analysis of Cu in water by collinear DP-LIBS].

PubMed

Zheng, Mei-Lan; Yao, Ming-Yin; Chen, Tian-Bing; Lin, Yong-Zeng; Li, Wen-Bing; Liu, Mu-Hua

2014-07-01

The purpose of this research is to study the influence of double pulse laser induced breakdown spectroscopy (DP-LIBS) on the sensitivity of Cu in water. The water solution of Cu was tested by collinear DP-LIBS in this article. The results show that spectral intensity of Cu can be enhanced obviously by DP-LIBS, compared with single pulse laser induced breakdown spectroscopy (SP-LIBS). Besides, the experimental results were significantly impacted by delay time between laser pulse and spectrometer acquisition, delay time of double laser pulse and energy of laser pulse and so on. The paper determined the best conditions for DP-LIBS detecting Cu in water. The optimal acquisition delay time was 1 380 ns. The best laser pulse delay time was 25 ns. The most appropriate energy of double laser pulse was 100 mJ. Characteristic analysis of spectra of Cu at 324.7 and 327.4 nm was done for quantitative analysis. The detection limit was 3.5 microg x mL(-1) at 324.7 nm, and the detection limit was 4.84 microg x mL(-1) at 327.4 nm. The relative standard deviation of the two characteristic spectral lines was within 10%. The calibration curve of characteristic spectral line, established by 327.4 nm, was verified with 500 microg x mL(-1) sample. Concentration of the sample was 446 microg x mL(-1) calculated by the calibration curve. This research shows that the detection sensitivity of Cu in water can be improved by DP-LIBS. At the same time, it had high stability.

Genome-wide profiling of DNA 5-hydroxymethylcytosine during rat Sertoli cell maturation

PubMed Central

Landfors, Miriam; Johansen, Jostein; Aronsen, Jan Magnus; Vågbø, Cathrine Broberg; Doré, Louis C; He, Chuan; Sjaastad, Ivar; Sætrom, Pål; Fedorcsák, Péter; Dahl, John Arne; Aanes, Håvard; Fußer, Markus; Klungland, Arne

2017-01-01

Sertoli cells have dual roles during the cells’ lifetime. In the juvenile mammal, Sertoli cells proliferate and create the structure of the testis, and during puberty they cease to proliferate and take on the adult role of supporting germ cells through spermatogenesis. Accordingly, many genes expressed in Sertoli cells during testis formation are repressed during spermatogenesis. 5-Hydroxymethylcytosine (5hmC) is a DNA modification enzymatically generated from 5mC and present in all investigated mammalian tissues at varying levels. Using mass spectrometry and immunofluorescence staining we identified a substantial Sertoli cell-specific global 5hmC increase during rat puberty. Chemical labeling, pull-down and sequencing of 5hmC-containing genomic DNA from juvenile and adult rat Sertoli cells revealed that genes that lose or gain 5hmC belong to different functional pathways and mirror the functions of the cells in the two different states. Loss of 5hmC is associated with genes involved in development and cell structure, whereas gain of 5hmC is associated with genes involved in cellular pathways pertaining to the function of the adult Sertoli cells. This redistribution during maturation shows that 5hmC is a dynamic nucleotide modification, correlated to gene expression. PMID:28529766

Non-professional marathon running: RAGE axis and ST2 family changes in relation to open-window effect, inflammation and renal function

PubMed Central

Bekos, Christine; Zimmermann, Matthias; Unger, Lukas; Janik, Stefan; Hacker, Philipp; Mitterbauer, Andreas; Koller, Michael; Fritz, Robert; Gäbler, Christian; Kessler, Mario; Nickl, Stefanie; Didcock, Jessica; Altmann, Patrick; Haider, Thomas; Roth, Georg; Klepetko, Walter; Ankersmit, Hendrik Jan; Moser, Bernhard

2016-01-01

Conflicting data exist on the relevance of marathon (M) and half marathon (HM) running for health. The number of non-professional athletes finishing M and HM events is steadily growing. In order to investigate molecular changes occurring in amateur athletes, we enrolled 70 non-professional runners finishing a single M (34) or HM (36) event at baseline, the finish line and during recovery, and 30 controls. The measurement of the Receptor for Advanced Glycation Endproducts, Interleukin 1 receptor antagonist, ST2 and cytokeratin 18 was combined with molecules measured during clinical routine. Results were analyzed in the light of blood cell analysis, lactate measurements, correction for changes in plasma volume and body composition assessments. There were intrinsic differences in body mass index, abdominal body fat percentage and training time between M and HM runners. C-reactive protein changes in M and HM runners. While soluble RAGE, AGEs and ST2 increased immediately after the race in HM runners, HMGB1 increased in HM and M after the race and declined to baseline after a recovery period. We give insights into the regulation of various molecules involved in physical stress reactions and their possible implications for the cardiovascular system or renal function. PMID:27653273

Site and mechanism of the colokinetic action of the ghrelin receptor agonist, HM01.

PubMed

Naitou, K; Mamerto, T P; Pustovit, R V; Callaghan, B; Rivera, L R; Chan, A J; Ringuet, M T; Pietra, C; Furness, J B

2015-12-01

It has been recently demonstrated that the ghrelin receptor agonist, HM01, caused defecation in rats that were treated to provide a model for the constipation of Parkinson's disease. HM01 significantly increased fecal output and increased Fos activity in neurons of the hypothalamus and hindbrain, but not in the spinal defecation center. Other ghrelin agonists act on the defecation center. Receptor pharmacology was examined in ghrelin receptor (GHSR1a) transfected cells. Anesthetized rats were used to investigate sites and mechanisms of action. HM01 activated rat GHSR1a at nanomolar concentrations and was antagonized by the GHSR1a antagonist, YIL781. HM01, intravenous, was potent to activate propulsive colorectal contractions. This was prevented by pelvic nerve section and by intravenous YIL781, but not by spinal cord section rostral to the defecation centers. Direct intrathecal application of HM01 to the defecation center at spinal level L6-S1 initiated propulsive contractions of the colorectum. HM01 stimulates GHSR1a receptors on neurons in the lumbosacral defecation centers to cause propulsive contractions and emptying of the colorectum. It has greater potency when given systemically, compared with other GHSR1a agonists. © 2015 John Wiley & Sons Ltd.

Use of a haemostatic matrix does not reduce blood loss in minimally invasive total knee arthroplasty

PubMed Central

Schwab, Pierre-Emmanuel; Thienpont, Emmanuel

2015-01-01

Background Blood loss can increase morbidity and the risk of transfusion after total knee arthroplasty (TKA). This study evaluated the difference in blood loss between minimally invasive TKA performed with and without intra-articular use of a haemostatic matrix (Floseal®). Materials and methods We retrospectively compared matched pairs in two groups (76 patients in each group): one group received conventional haemostasis (with bovie electrocoagulation), the other group was treated with an intra-articular haemostatic matrix (HM) as an adjunct to electrocoagulation. The outcomes compared were haemoglobin (Hb) and haematocrit levels at days 2 and 4 after surgery as a surrogate for blood loss, transfusion rate, surgical time, preoperative and postoperative range of motion (ROM) at days 21 and 42 and length of stay (LOS) in hospital. Results No differences were observed for Hb levels at day 2 or day 4 between men in the two groups. In women, however, the mean Hb at day 2 was 11.1 g/dL (SD 1.3) for TKA with HM and 12.0 g/dL (SD 0.9) for TKA without HM (p<0.001), while that at day 4 was 10.6 g/dL (SD 1.3) for TKA with HM and 11.4 g/dL (SD 1.2) for TKA without HM (p<0.001). The haematocrit was higher for TKA without HM at day 2 (p=0.001) and day 4 (p=0.008). The transfusion rate for TKA with HM was 2.6% and for TKA without HM 0% (p=0.497), while the mean surgical time was 93 minutes (SD 12) vs 87 minutes (SD 14), respectively (p=0.0055). There were no differences in preoperative or postoperative ROM at days 21 and 42 between the two groups. The LOS was longer for TKA with HM than for TKA without HM (4.5 days and 4 days, respectively, p=0.011) influenced by the longer stay for the transfused patients. Discussion The present study showed that the use of Floseal had no effect on reducing either visible or hidden blood loss after TKA, as assessed by a drop in Hb or haematocrit and that hidden blood loss was more important in women treated with the HM. PMID:25761324

libRoadRunner: a high performance SBML simulation and analysis library

PubMed Central

Somogyi, Endre T.; Bouteiller, Jean-Marie; Glazier, James A.; König, Matthias; Medley, J. Kyle; Swat, Maciej H.; Sauro, Herbert M.

2015-01-01

Motivation: This article presents libRoadRunner, an extensible, high-performance, cross-platform, open-source software library for the simulation and analysis of models expressed using Systems Biology Markup Language (SBML). SBML is the most widely used standard for representing dynamic networks, especially biochemical networks. libRoadRunner is fast enough to support large-scale problems such as tissue models, studies that require large numbers of repeated runs and interactive simulations. Results: libRoadRunner is a self-contained library, able to run both as a component inside other tools via its C++ and C bindings, and interactively through its Python interface. Its Python Application Programming Interface (API) is similar to the APIs of MATLAB (www.mathworks.com) and SciPy (http://www.scipy.org/), making it fast and easy to learn. libRoadRunner uses a custom Just-In-Time (JIT) compiler built on the widely used LLVM JIT compiler framework. It compiles SBML-specified models directly into native machine code for a variety of processors, making it appropriate for solving extremely large models or repeated runs. libRoadRunner is flexible, supporting the bulk of the SBML specification (except for delay and non-linear algebraic equations) including several SBML extensions (composition and distributions). It offers multiple deterministic and stochastic integrators, as well as tools for steady-state analysis, stability analysis and structural analysis of the stoichiometric matrix. Availability and implementation: libRoadRunner binary distributions are available for Mac OS X, Linux and Windows. The library is licensed under Apache License Version 2.0. libRoadRunner is also available for ARM-based computers such as the Raspberry Pi. http://www.libroadrunner.org provides online documentation, full build instructions, binaries and a git source repository. Contacts: hsauro@u.washington.edu or somogyie@indiana.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26085503

Novel Estimation of the Humification Degree of Soil Organic Matter by Laser-Induced Breakdown Spectroscopy (LIBS) Compared to Laser-Induced Fluorescence Spectroscopy (LIFS)

NASA Astrophysics Data System (ADS)

Ferreira, Edilene; Ferreira, Ednaldo; Villas-Boas, Paulino; Senesi, Giorgio; Carvalho, Camila; Romano, Renan; Martin-Neto, Ladislau; Milori, Debora

2014-05-01

Soil organic matter (SOM) constitutes an important reservoir of terrestrial carbon and can be considered an alternative for atmospheric carbon storage, contributing to global warming mitigation. Soil management can favor atmospheric carbon incorporation into SOM or its release from SOM to atmosphere. Thus, the evaluation of the humification degree (HD), which is an indication of the recalcitrance of SOM, can provide an estimation of the capacity of carbon sequestration in soils under various managements. The HD of SOM can be estimated by using various analytical techniques including fluorescence spectroscopy. In the present work, the potential of Laser-Induced Breakdown Spectroscopy (LIBS) to estimate the HD of SOM was evaluated for the first time. In a LIBS experiment a high-energy laser pulse irradiates the sample and the energy absorbed by the sample causes a local heating of the material that results in its evaporation or sublimation. The high temperature of the ablated material generates a small plasma plume and, as a result of the plasma temperature, the ablated material breaks down into excited atomic and ionic species. During the plasma cooling, the excited species return to their lower energy state emitting electromagnetic radiation at characteristic wavelengths. In a LIBS spectrum the measurement of the characteristic emission wavelengths provides qualitative information about the elemental composition of the sample, whereas the intensities of the signals can be used for quantitative determinations. The LIBS potential for the analysis of organic compounds has been explored recently by using the emission lines of elements that are commonly present in organic compounds, such as the predominant C, H, P, O and N. LIBS elemental emissions were correlated to fluorescence emissions determined by Laser-Induced Fluorescence Spectroscopy (LIFS), which was considered as the reference technique. The HD of SOM determined by LIBS showed a strong correlation to that determined by LIFS, suggesting a great potential of LIBS for this novel application.

Qualitative and quantitative spectro-chemical analysis of dates using UV-pulsed laser induced breakdown spectroscopy and inductively coupled plasma mass spectrometry.

PubMed

Mehder, A O; Habibullah, Y B; Gondal, M A; Baig, Umair

2016-08-01

Laser Induced Breakdown Spectroscopy (LIBS) is demonstrated for the spectral analysis of nutritional and toxic elements present in several varieties of date fruit samples available in the Saudi Arabia market. The method analyzes the optical emission of a test sample when subjected to pulsed laser ablation. In this demonstration, our primary focus is on calcium (Ca) and magnesium (Mg), as nutritional elements, and on chromium (Cr), as a toxic element. The local thermodynamic equilibrium (LTE) condition was confirmed prior to the elemental characterization of date samples to ensure accuracy of the LIBS analysis. This was achieved by measuring parameters associated with the plasma, such as the electron temperature and the electron number density. These plasma parameters aid interpretation of processes such as ionization, dissociation, and excitation occurring in the plasma plume formed by ablating the date palm sample. The minimum detection limit was established from calibration curves that involved plotting the LIBS signal intensity as a function of standard date samples with known concentrations. The concentration of Ca and Mg detected in different varieties of date samples was between 187 and 515 and 35-196mgL(-1) respectively, while Cr concentration measured between 1.72 and 7.76mgL(-1). In order to optimize our LIBS system, we have studied how the LIBS signal intensity depends on the incident laser energy and the delay time. In order to validate our LIBS analysis results, standard techniques such as inductively coupled plasma mass spectrometry (ICP-MS) were also applied on an identical (duplicate) date samples as those used for the LIBS analysis. The LIBS results exhibit remarkable agreement with those obtained from the ICP-MS analysis. In addition, the finger print wavelengths of other elements present in date samples were also identified and are reported here, which has not been previously reported, to the best of our knowledge. Copyright © 2016 Elsevier B.V. All rights reserved.

libRoadRunner: a high performance SBML simulation and analysis library.

PubMed

Somogyi, Endre T; Bouteiller, Jean-Marie; Glazier, James A; König, Matthias; Medley, J Kyle; Swat, Maciej H; Sauro, Herbert M

2015-10-15

This article presents libRoadRunner, an extensible, high-performance, cross-platform, open-source software library for the simulation and analysis of models expressed using Systems Biology Markup Language (SBML). SBML is the most widely used standard for representing dynamic networks, especially biochemical networks. libRoadRunner is fast enough to support large-scale problems such as tissue models, studies that require large numbers of repeated runs and interactive simulations. libRoadRunner is a self-contained library, able to run both as a component inside other tools via its C++ and C bindings, and interactively through its Python interface. Its Python Application Programming Interface (API) is similar to the APIs of MATLAB ( WWWMATHWORKSCOM: ) and SciPy ( HTTP//WWWSCIPYORG/: ), making it fast and easy to learn. libRoadRunner uses a custom Just-In-Time (JIT) compiler built on the widely used LLVM JIT compiler framework. It compiles SBML-specified models directly into native machine code for a variety of processors, making it appropriate for solving extremely large models or repeated runs. libRoadRunner is flexible, supporting the bulk of the SBML specification (except for delay and non-linear algebraic equations) including several SBML extensions (composition and distributions). It offers multiple deterministic and stochastic integrators, as well as tools for steady-state analysis, stability analysis and structural analysis of the stoichiometric matrix. libRoadRunner binary distributions are available for Mac OS X, Linux and Windows. The library is licensed under Apache License Version 2.0. libRoadRunner is also available for ARM-based computers such as the Raspberry Pi. http://www.libroadrunner.org provides online documentation, full build instructions, binaries and a git source repository. hsauro@u.washington.edu or somogyie@indiana.edu Supplementary data are available at Bioinformatics online. Published by Oxford University Press 2015. This work is written by US Government employees and is in the public domain in the US.

Combined Raman/LIBS spectrometer elegant breadboard: built and tested - and flight model spectrometer unit

NASA Astrophysics Data System (ADS)

Ahlers, B.; Hutchinson, I.; Ingley, R.

2017-11-01

A spectrometer for combined Raman and Laser Induced Breakdown Spectroscopy (LIBS) is amongst the different instruments that have been pre-selected for the Pasteur payload of the ExoMars rover. It is regarded as a fundamental, next-generation instrument for organic, mineralogical and elemental characterisation of Martian soil, rock samples and organic molecules. Raman spectroscopy and LIBS will be integrated into a single instrument sharing many hardware commonalities [1]. The combined Raman / LIBS instrument has been recommended as the highest priority mineralogy instrument to be included in the rover's analytical laboratory for the following tasks: Analyse surface and sub-surface soil and rocks on Mars, identify organics in the search for life and determine soil origin & toxicity. The synergy of the system is evident: the Raman spectrometer is dedicated to molecular analysis of organics and minerals; the LIBS provides information on the sample's elemental composition. An international team, under ESA contract and with the leadership of TNO Science and Industry, has built and tested an Elegant Bread Board (EBB) of the combined Raman / LIBS instrument. The EBB comprises a specifically designed, extremely compact, spectrometer with high resolution over a large wavelength range, suitable for both Raman spectroscopy and LIBS measurements. The EBB also includes lasers, illumination and imaging optics as well as fibre optics for light transfer. A summary of the functional and environmental requirements together with a description of the optical design and its expected performance are described in [2]. The EBB was developed and constructed to verify the instruments' end-to-end functional performance with natural samples. The combined Raman / LIBS EBB realisation and test results of natural samples will be presented. For the Flight Model (FM) instrument, currently in the design phase, the Netherlands will be responsible for the design, development and verification of the spectrometer unit, while the UK provides the detector. The differences between the EBB and the FM will be demonstrated.

In situ semi-quantitative analysis of polluted soils by laser-induced breakdown spectroscopy (LIBS).

PubMed

Ismaël, Amina; Bousquet, Bruno; Michel-Le Pierrès, Karine; Travaillé, Grégoire; Canioni, Lionel; Roy, Stéphane

2011-05-01

Time-saving, low-cost analyses of soil contamination are required to ensure fast and efficient pollution removal and remedial operations. In this work, laser-induced breakdown spectroscopy (LIBS) has been successfully applied to in situ analyses of polluted soils, providing direct semi-quantitative information about the extent of pollution. A field campaign has been carried out in Brittany (France) on a site presenting high levels of heavy metal concentrations. Results on iron as a major component as well as on lead and copper as minor components are reported. Soil samples were dried and prepared as pressed pellets to minimize the effects of moisture and density on the results. LIBS analyses were performed with a Nd:YAG laser operating at 1064 nm, 60 mJ per 10 ns pulse, at a repetition rate of 10 Hz with a diameter of 500 μm on the sample surface. Good correlations were obtained between the LIBS signals and the values of concentrations deduced from inductively coupled plasma atomic emission spectroscopy (ICP-AES). This result proves that LIBS is an efficient method for optimizing sampling operations. Indeed, "LIBS maps" were established directly on-site, providing valuable assistance in optimizing the selection of the most relevant samples for future expensive and time-consuming laboratory analysis and avoiding useless analyses of very similar samples. Finally, it is emphasized that in situ LIBS is not described here as an alternative quantitative analytical method to the usual laboratory measurements but simply as an efficient time-saving tool to optimize sampling operations and to drastically reduce the number of soil samples to be analyzed, thus reducing costs. The detection limits of 200 ppm for lead and 80 ppm for copper reported here are compatible with the thresholds of toxicity; thus, this in situ LIBS campaign was fully validated for these two elements. Consequently, further experiments are planned to extend this study to other chemical elements and other matrices of soils.

[Laser-induced breakdown spectroscopy system for elements analysis in high-temperature and vacuum environment].

PubMed

Pan, Cong-Yuan; Du, Xue-Wei; An, Ning; Han, Zhen-Yu; Wang, Sheng-Bo; Wei, Wei; Wang, Qiu-Ping

2013-12-01

Laser-induced breakdown spectroscopy (LIBS) is one of the most promising technologies to be applied to metallurgical composition online monitoring in these days. In order to study the spectral characters of LIBS spectrum and to investigate the quantitative analysis method of material composition under vacuum and high temperature environment, a LIBS measurement system was designed and set up which can be used for conducting experiments with high-temperature or molten samples in different vacuum environment. The system consists of a Q-switched Nd : YAG laser used as the light source, lens with different focus lengths used for laser focusing and spectrum signal collecting, a spectrometer used for detecting the signal of LIBS spectrums, and a vacuum system for holding and heating the samples while supplying a vacuum environment. The vacuum was achieved and maintained by a vacuum pump and an electric induction furnace was used for heating the system. The induction coil was integrated to the vacuum system by attaching to a ceramic sealing flange. The system was installed and testified, and the results indicate that the vacuum of the system can reach 1X 10(-4) Pa without heating, while the heating temperature could be about 1 600 degreeC, the system can be used for melting metal samples such as steel and aluminum and get the LIBS spectrum of the samples at the same time. Utilizing this system, LIBS experiments were conducted using standard steel samples under different vacuum or high-temperature conditions. Results of comparison between LIBS spectrums of solid steel samples under different vacuum were achieved, and so are the spectrums of molten and solid steel samples under vacuum environment. Through data processing and theoretical analyzing of these spectrums, the initial results of those experiments are in good agreement with the results that are presently reported, which indicates that the whole system functions well and is available for molten metal LIBS experiment under vacuum environment.

A narrowband imaging survey of symbiotic stars

NASA Astrophysics Data System (ADS)

Corradi, Romano L. M.; Brandi, Estela; Ferrer, Osvaldo E.; Schwarz, Hugo E.

1999-03-01

Narrowband images of 51 symbiotic stars were obtained at the ESO and ORM observatories to search for resolved optical nebulae. Ionized nebulae much larger than previously known are found around CH Cyg, HM Sge and V1016 Cyg, and they will be discussed in detail in forthcoming papers. A nebula with a deconvolved size between 0\\farcs9 and 1\\farcs5 is found around the symbiotic Mira H 1-36. The radio sources located few arcminutes aside of R Aqr (Hollis et al. 1987), which were suggested to be the remnant of a prehistoric eruption of the system, are found to be background galaxies. We also present a bibliographical compilation, updated to October 1998, of all the extended nebulae around symbiotic stars detected at optical and radio wavelengths, as well as a list of optical non-detections. The statistics of occurrence of these large ionized nebulae among symbiotic stars is discussed. Extended ionized nebulae appear to be a common component of the D-type symbiotics, and we infer that they are formed by the Mira wind and/or high velocity winds ejected by the hot component during outbursts. On the contrary, very few nebulae are detected around the systems containing normal red giants. Table 5 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html. Based on observations obtained at the 3.5m~NTT and 1.5m~DAN telescopes of the European Southern Observatory, and at the 2.6m~NOT telescope operated on the island of La Palma by NOTSA, in the Spanish Observatorio del Roque de Los Muchachos of the Instituto de Astrofisica de Canarias.

Variation of hmF2 and NmF2 deduced from DPS-4 over Multan (Pakistan) and their comparisons with IRI-2012 & IRI-2016 during the deep solar minimum between cycles 23 & 24

NASA Astrophysics Data System (ADS)

Ameen, Muhammad Ayyaz; Khursheed, Haqqa; Jabbar, Mehak Abdul; Ali, Muneeza Salman; Chishtie, Farrukh

2018-04-01

We report the results of ionospheric measurements from DPS-4 installed at Multan (Geog coord. 30.18°N, 71.48°E, dip 47.4°). The variations in F2-layer maximum electron density NmF2 and its peak height hmF2 are studied during the deep solar minimum between cycles 23 & 24 i.e 2008-2009 with comparisons conducted with the International Reference Ionosphere (IRI) versions 2012 & 2016. We find that the hmF2 observations peak around the pre-sunrise and sunrise hours depending on the month. Seasonally, the daytime variation of NmF2 is higher in the Equinox and Summer, while daytime hmF2 are slightly higher in the Equinox and Winter. High values of hmF2 around midnight are caused by an increase of upward drifts produced by meridional winds. The ionosphere over Multan, which lies at the verge of low and mid latitude, is affected by both E × B drifts and thermospheric winds as evident from mid-night peaks and near-sunrise dips in hmF2. The results of the comparison of the observed NmF2 and hmF2 for the year 2008-2009 with the IRI-2012 (both NmF2 and hmF2) and IRI-2016 (only hmF2) estimates indicate that for NmF2, IRI-2012 with Consultative Committee International Radio (CCIR) option produces values in better agreement with observed data. Whereas, for hmF2, IRI-2016 with both International Union of Radio Science (URSI) and CCIR SHU-2015 options, predicts well for nighttime hours throughout the year. However, the IRI-2012 with CCIR option produces better agreement with data during daytime hours. Furthermore, IRI-2012 with CCIR option gives better results during Equinox months, whereas, IRI-2016 with both URSI and CCIR SHU-2015 options predict well for Winter and Summer.

Circulating levels of 3-hydroxymyristate, a direct quantification of endotoxemia in non-infected cirrhotic patients.

PubMed

Weil, Delphine; Pais de Barros, Jean-Paul; Mourey, Guillaume; Laheurte, Caroline; Cypriani, Benoit; Badet, Nicolas; Delabrousse, Eric; Grandclément, Emilie; Di Martino, Vincent; Saas, Philippe; Lagrost, Laurent; Thévenot, Thierry

2018-06-22

The quantification of lipopolysaccharide (LPS) in biological fluids is challenging. We aimed to measure plasma LPS concentration using a new method of direct quantification of 3-hydroxymyristate (3-HM), a lipid component of LPS, and to evaluate correlations between 3-HM and markers of liver function, endothelial activation, portal hypertension and enterocyte damage. Plasma from 90 non-infected cirrhotic patients (30 Child-Pugh [CP]-A, 30 CP-B, 30 CP-C) was prospectively collected. The concentration of 3-HM was determined by High Performance Liquid Chromatography coupled with Mass Spectrometry. 3-HM levels were higher in CP-C patients (CP-A/CP-B/CP-C: 68/70/103 ng/mL, p=0.005). Patients with severe acute alcoholic hepatitis (n=16; 113 vs 74 ng/mL,p=0.012), diabetic patients (n=22; 99 vs 70 ng/mL, p=0.028) and those not receiving beta-blockers (n=44; 98 vs 72 ng/mL, p=0.034) had higher levels of 3-HM. We observed a trend towards higher baseline levels of 3-HM in patients with hepatic encephalopathy (n=7; 144 vs 76 ng/mL, p=0.45) or SIRS (n=10; 106 vs 75 ng/mL, p=0.114). In multivariate analysis, high levels of 3-HM were associated with CP (OR=4.39; 95%CI=1.79-10.76) or MELD (OR=8.24; 95%CI=3.19-21.32) scores. Patients dying from liver insufficiency (n=6) during a 12-month follow-up had higher baseline levels of 3-HM (106 vs 75 ng/mL, p=0.089). In non-infected cirrhotic patients, 3-HM arises more frequently with impairment of liver function, heavy alcohol consumption, diabetic status, non-use of beta-blockers, and a trend towards poorer outcome is also observed. The direct mass-measurement of LPS using 3-HM appears reliable to detect transient endotoxemia and promising to manage the follow-up of cirrhotic patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Improvement of desolvation and resilience of alginate binders for Si-based anodes in a lithium ion battery by calcium-mediated cross-linking.

PubMed

Yoon, Jihee; Oh, Dongyeop X; Jo, Changshin; Lee, Jinwoo; Hwang, Dong Soo

2014-12-14

Si-based anodes in lithium ion batteries (LIBs) have exceptionally high theoretical capacity, but the use of a Si-based anode in LIBs is problematic because the charging-discharging process can fracture the Si particles. Alginate and its derivatives show promise as Si particle binders in the anode. We show that calcium-mediated "egg-box" electrostatic cross-linking of alginate improves toughness, resilience, electrolyte desolvation of the alginate binder as a Si-binder for LIBs. Consequently, the improved mechanical properties of the calcium alginate binder compared to the sodium alginate binder and other commercial binders extend the lifetime and increase the capacity of Si-based anodes in LIBs.

5-Hydroxymethylcytosine-mediated alteration of transposon activity associated with the exposure to adverse in utero environments in human.

PubMed

Sun, Miao; Song, Mingxi M; Wei, Bin; Gao, Qinqin; Li, Lingjun; Yao, Bing; Chen, Li; Lin, Li; Dai, Qing; Zhou, Xiuwen; Tao, Jianying; Chen, Jie; He, Chuan; Jin, Peng; Xu, Zhice

2016-06-01

Preeclampsia and gestational diabetes mellitus (GDM) are the most common clinical conditions in pregnancy that could result in adverse in utero environments. Fetal exposure to poor environments may raise the long-term risk of postnatal disorders, while epigenetic modifications could be involved. Recent research has implicated involvement of 5-hydroxymethylcytosine (5hmC), a DNA base derived from 5-methylcytosine, via oxidation by ten-eleven translocation (TET) enzymes, in DNA methylation-related plasticity. Here, we show that the TET2 expression and 5hmC abundance are significantly altered in the umbilical veins of GDM and preeclampsia. Genome-wide profiling of 5hmC revealed its specific reduction on intragenic regions from both GDM and preeclampsia compared to healthy controls. Gene Ontology analysis using loci bearing unique GDM- and preeclampsia-specific loss-of-5hmC indicated its impact on several critical biological pathways. Interestingly, the substantial alteration of 5hmC on several transposons and repetitive elements led to their differential expression. The alteration of TET expression, 5hmC levels and 5hmC-mediated transposon activity was further confirmed using established hypoxia cell culture model, which could be rescued by vitamin C, a known activator of TET proteins. Together, these results suggest that adverse pregnancy environments could influence 5hmC-mediated epigenetic profile and contribute to abnormal development of fetal vascular systems that may lead to postnatal diseases. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Spatial pattern of forest biomass and its influencing factors in the Great Xing'an Mountains, Heilongjiang Province, China].

PubMed

Wang, Xiao-Li; Chang, Yu; Chen, Hong-Wei; Hu, Yuan-Man; Jiao, Lin-Lin; Feng, Yu-Ting; Wu, Wen; Wu, Hai-Feng

2014-04-01

Based on field inventory data and vegetation index EVI (enhanced vegetation index), the spatial pattern of the forest biomass in the Great Xing'an Mountains, Heilongjiang Province was quantitatively analyzed. Using the spatial analysis and statistics tools in ArcGIS software, the impacts of climatic zone, elevation, slope, aspect and vegetation type on the spatial pattern of forest biomass were explored. The results showed that the forest biomass in the Great Xing'an Mountains was 350 Tg and spatially aggregated with great increasing potentials. Forest biomass density in the cold temperate humid zone (64.02 t x hm(-2)) was higher than that in the temperate humid zone (60.26 t x hm(-2)). The biomass density of each vegetation type was in the order of mixed coniferous forest (65.13 t x hm(-2)) > spruce-fir forest (63.92 t x hm(-2)) > Pinus pumila-Larix gmelinii forest (63.79 t x hm(-2)) > Pinus sylvestris var. mongolica forest (61.97 t x hm(-2)) > Larix gmelinii forest (61.40 t x hm(-2)) > deciduous broadleaf forest (58.96 t x hm(-2)). With the increasing elevation and slope, the forest biomass density first decreased and then increased. The forest biomass density in the shady slopes was greater than that in the sunny slopes. The spatial pattern of forest biomass in the Great Xing' an Mountains exhibited a heterogeneous pattern due to the variation of climatic zone, vegetation type and topographical factor. This spatial heterogeneity needs to be accounted when evaluating forest biomass at regional scales.

Histogram Matching Extends Acceptable Signal Strength Range on Optical Coherence Tomography Images

PubMed Central

Chen, Chieh-Li; Ishikawa, Hiroshi; Wollstein, Gadi; Bilonick, Richard A.; Sigal, Ian A.; Kagemann, Larry; Schuman, Joel S.

2015-01-01

Purpose. We minimized the influence of image quality variability, as measured by signal strength (SS), on optical coherence tomography (OCT) thickness measurements using the histogram matching (HM) method. Methods. We scanned 12 eyes from 12 healthy subjects with the Cirrus HD-OCT device to obtain a series of OCT images with a wide range of SS (maximal range, 1–10) at the same visit. For each eye, the histogram of an image with the highest SS (best image quality) was set as the reference. We applied HM to the images with lower SS by shaping the input histogram into the reference histogram. Retinal nerve fiber layer (RNFL) thickness was automatically measured before and after HM processing (defined as original and HM measurements), and compared to the device output (device measurements). Nonlinear mixed effects models were used to analyze the relationship between RNFL thickness and SS. In addition, the lowest tolerable SSs, which gave the RNFL thickness within the variability margin of manufacturer recommended SS range (6–10), were determined for device, original, and HM measurements. Results. The HM measurements showed less variability across a wide range of image quality than the original and device measurements (slope = 1.17 vs. 4.89 and 1.72 μm/SS, respectively). The lowest tolerable SS was successfully reduced to 4.5 after HM processing. Conclusions. The HM method successfully extended the acceptable SS range on OCT images. This would qualify more OCT images with low SS for clinical assessment, broadening the OCT application to a wider range of subjects. PMID:26066749

Risk factors and management of positive horizontal margin in early gastric cancer resected by en bloc endoscopic submucosal dissection.

PubMed

Numata, Norifumi; Oka, Shiro; Tanaka, Shinji; Kagemoto, Kenichi; Sanomura, Yoji; Yoshida, Shigeto; Arihiro, Koji; Shimamoto, Fumio; Chayama, Kazuaki

2015-04-01

Although endoscopic submucosal dissection (ESD) is a widely accepted treatment for early gastric cancer (EGC), there is no consensus regarding the management of positive horizontal margin (HM) despite en bloc ESD. The aim of the current study was to identify the risk factors and optimal management of positive HM in EGCs resected by en bloc ESD. A total of 890 consecutive patients with 1,053 intramucosal EGCs resected by en bloc ESD between April 2005 and June 2011. Clinicopathological data were retrieved retrospectively to assess the positive HM rate, local recurrence rate, risk factors for positive HM, and outcomes of treatment for local recurrent tumor. Positive HM was defined as a margin with direct tumor invasion (type A), the presence of cancerous cells on either end of 2-mm-thick cut sections (type B), or an unclear tumor margin resulting from crush or burn damage (type C). The positive HM rate was 2.0% (21/1,053). The local recurrence rate was 0.3% (3/1,053). All local recurrent tumors were intramucosal carcinomas, and were resected curatively by re-ESD. Multivariate analysis with logistic regression showed tumor location in the upper third of the stomach and lesions not matching the absolute indication to be independent risk factors for positive HM. The risk factors for HM positivity in cases of EGC resected by en bloc ESD are tumor location in the upper third of the stomach and dissatisfaction of the absolute indication for curative ESD.

Manganese Oxide Nanoarray-Based Monolithic Catalysts: Tunable Morphology and High Efficiency for CO Oxidation

DOE PAGES

Chen, Sheng-Yu; Song, Wenqiao; Lin, Hui-Jan; ...

2016-03-08

In this work, a generic one-pot hydrothermal synthesis route has been successfully designed and utilized to in situ grow uniform manganese oxide nanorods and nanowires onto the cordierite honeycomb monolithic substrates, forming a series of nanoarray-based monolithic catalysts. During the synthesis process, three types of potassium salt oxidants have been used with different reduction potentials, i.e., K 2Cr 2O 7, KClO 3, and K 2S 2O 8, denoted as HM-DCM, HM-PCR, and HM-PSF, respectively. The different reduction potentials of the manganese source (Mn 2+) and oxidants induced the formation of manganese oxide nanoarrays with different morphology, surface area, and reactivitymore » of carbon monoxide (CO) oxidation. K 2Cr 2O 7 and KClO 3 can induce sharp and long nanowires with slow growth rates due to their low reduction potentials. In comparison, the nanoarrays of HM-PSF presented shorter nanorods but displayed an efficient 90% CO oxidation conversion at 200 °C (T90) without noble-metal loading. Reducibility tests for the three monolithic catalysts by hydrogen temperature-programmed reduction revealed an activation energy order of HM-PSF > HM-DCM > HM-PCR for CO oxidation. The characterizations of oxygen temperature-programmed desorption and X-ray photoelectron spectroscopy indicated the abundant surface-adsorbed oxygen and lattice oxygen contributing to the superior reactivity of HM-PSF. Finally, the straightforward synthetic process showed a scalable, low-cost, and template-free method to fabricate manganese oxide nanoarray monolithic catalysts for exhaust treatment.« less

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2013-08-13

.../Jackson, Mississippi; Authorization of Production Activity; Extension of Production Authority; H.M... the Foreign-Trade Zones (FTZ) Board on behalf of H.M. Richards, Inc., in Guntown, Mississippi. The...) is limited to 6.5 million square yards. 2. H.M. Richards, Inc., must admit all foreign upholstery...

Publications - Beikman, H.M., 1980 | Alaska Division of Geological &

Science.gov Websites

main content USGS Beikman, H.M., 1980 Publication Details Title: Geologic map of Alaska Authors Warehouse Bibliographic Reference Beikman, H.M., 1980, Geologic map of Alaska: U.S. Geological Survey, 1 USGS website Maps & Other Oversized Sheets Maps & Other Oversized Sheets Sheet 1 Geologic Map

Understanding the Molecular Mechanisms of the Interplay Between Herbal Medicines and Gut Microbiota.

PubMed

Xu, Jun; Chen, Hu-Biao; Li, Song-Lin

2017-09-01

Herbal medicines (HMs) are much appreciated for their significant contribution to human survival and reproduction by remedial and prophylactic management of diseases. Defining the scientific basis of HMs will substantiate their value and promote their modernization. Ever-increasing evidence suggests that gut microbiota plays a crucial role in HM therapy by complicated interplay with HM components. This interplay includes such activities as: gut microbiota biotransforming HM chemicals into metabolites that harbor different bioavailability and bioactivity/toxicity from their precursors; HM chemicals improving the composition of gut microbiota, consequently ameliorating its dysfunction as well as associated pathological conditions; and gut microbiota mediating the interactions (synergistic and antagonistic) between the multiple chemicals in HMs. More advanced experimental designs are recommended for future study, such as overall chemical characterization of gut microbiota-metabolized HMs, direct microbial analysis of HM-targeted gut microbiota, and precise gut microbiota research model development. The outcomes of such research can further elucidate the interactions between HMs and gut microbiota, thereby opening a new window for defining the scientific basis of HMs and for guiding HM-based drug discovery. © 2016 Wiley Periodicals, Inc.

Carbachol dimers as homobivalent modulators of muscarinic receptors.

PubMed

Matucci, Rosanna; Nesi, Marta; Martino, Maria Vittoria; Bellucci, Cristina; Manetti, Dina; Ciuti, Elisa; Mazzolari, Angelica; Dei, Silvia; Guandalini, Luca; Teodori, Elisabetta; Vistoli, Giulio; Romanelli, Maria Novella

2016-05-15

A series of homodimers of the well-known cholinergic agonist carbachol have been synthesized, showing the two agonist units symmetrically connected through a methylene chain of variable length. The new compounds have been tested on the five cloned muscarinic receptors (hM1-5) expressed in CHO cells by means of equilibrium binding studies, showing an increase in affinity by rising the number of methylene units up to 7 and 9. Functional experiments on guinea-pig ileum and assessment of ERK1/2 phosphorylation on hM1, hM2 and hM3 on CHO cells have shown that the new compounds are endowed with muscarinic antagonistic properties. Kinetic binding studies have revealed that some of the tested compounds are able to slow the rate of dissociation of NMS, suggesting a bitopic behavior. Docking simulations, performed on the hM1 and hM2 receptors, give a sound rationalization of the experimental data revealing how these compounds are able to interact with both orthosteric and allosteric binding sites depending on the length of their connecting chain. Copyright © 2016 Elsevier Inc. All rights reserved.

[Impact of land use type on stability and organic carbon of soil aggregates in Jinyun Mountain].

PubMed

Li, Jian-Lin; Jiang, Chang-Sheng; Hao, Qing-Ju

2014-12-01

Soil aggregates have the important effect on soil fertility, soil quality and the sustainable utilization of soil, and they are the mass bases of water and fertilizer retention ability of soil and the supply or release of soil nutrients. In this paper, in order to study the impact of land use type on stability and organic carbon of soil aggregates in Jinyun Mountain, we separated four land use types of soil, which are woodland, abandoned land, orchard and sloping farmland by wet sieving method, then we got the proportion of large macroaggregates (> 2 mm), small macroaggregates (0.25-2 mm), microaggregates (53 μm-0.25 mm) and silt + clay (< 53 μm) and measured the content of organic carbon in each aggregate fraction in soil depth of 0-60 cm and calculated the total content of organic carbon of all aggregates fraction in each soil. The results showed that reclamation of woodland will lead to fragmentation of macroaggregates and deterioration of soil structure, and the proportion of macroaggrgates (> 0.25 mm) were 44.62% and 32.28% respectively in the soils of orchard and sloping farmland, which reduced 38.58% (P < 0.05) and 91.52% (P < 0.05) compared with woodland. While after changing the sloping farmland to abandoned land, which lead to the conversion of soil fraction from silt + clay to large macroaggregates and small macroaggregates, so it will improve the soil structure. MWD (mean weight diameter) and GMD (geometric mean diameter) are important indicators of evaluating the stability of soil aggregates. We found the MWD and GWD in soil depth of 0-60 cm in orchards and sloping farmland were significantly lower than those in woodland (P < 0.05), while after changing the sloping farmland to abandoned land, the MWD and GWD increased significantly (P < 0.05), which indicated that reclamation of woodland will lead to the decrease of stability of soil aggregates, and they will be separated more easily by water. However, after changing the sloping farmland to abandoned land will enhance the stability of soil aggregates, and improve the ability of soil to resist external damage. The organic carbon content in each soil aggregate of four land use types decreased with the increase of soil depth. In soil depth of 0-60 cm, the storage of organic carbon of large macroaggregates in each soil are in orders of woodland (14.98 Mg x hm(-2)) > abandoned land (8.71 Mg x hm(-2)) > orchard (5.82 Mg x hm(-2)) > sloping farmland (2.13 Mg x hm(-2)), and abandoned land (35.61 Mg x hm(-2)) > woodland (20.38 Mg x hm-(-2)) > orchard (13.83 Mg x hm(-2)) > sloping farmland (6.77 Mg x hm(-2)) in small macroaggregates, and abandoned land (22.44 Mg x hm(-2)) > woodland (10.20 Mg x hm(-2)) > orchard (6.80 Mg x hm(-2)) > sloping farmland (5. 60 Mg x hm(-2)) in microaggregates, and abandoned land (22.21 Mg x hm(-2)) > woodland (17.01 Mg x hm(-2)) > orchard (16.70 Mg x hm(-2)) > sloping farmland (9.85 Mg x hm(-2)) in silt and clay fraction. Storage of organic carbon in each aggregate in the soils of woodland and abandoned land were higher than those in the soils of orchard and sloping farmland, which indicated that reclamation of woodland will lead to a loss of organic carbon in each soil aggregate fraction, while after changing the sloping farmland to abandoned land will contribute to restore and sequestrate the soil organic carbon. In addition, it showed that most organic carbon accumulated in small macroaggregate in soils of woodland and abandoned land, while they are in silt and clay in soils of orchard and sloping farmland, indicating that organic carbon in larger aggregates is unstable and is easier to convert during the land use change.

Human milk insulin is related to maternal plasma insulin and BMI: but other components of human milk do not differ by BMI.

PubMed

Young, B E; Patinkin, Z; Palmer, C; de la Houssaye, B; Barbour, L A; Hernandez, T; Friedman, J E; Krebs, N F

2017-09-01

The impact of maternal BMI and insulin sensitivity on bioactive components of human milk (HM) is not well understood. As the prevalence of obesity and diabetes rises, it is increasingly critical that we understand how maternal BMI and hormones associated with metabolic disease relate to concentrations of bioactive components in HM. This longitudinal cohort design followed 48 breastfeeding mothers through the first four months of lactation, collecting fasting morning HM samples at 2-weeks and 1, 2, 3 and 4-months, and fasting maternal blood at 2-weeks and 4-months. Insulin, glucose, adipokines leptin and adiponectin, appetite regulating hormone ghrelin, marker of oxidative stress 8OHdG and inflammatory cytokines (IL-6, IL-8, and TNF-a) were measured in HM and maternal plasma. A total of 26 normal weight (NW) (BMI=21.4±2.0 kg/m 2 ) and 22 overweight/obese (OW/Ob) (BMI=30.4±4.2 kg/m 2 ) were followed. Of all HM analytes measured, only insulin and leptin were different between groups - consistently higher in the OW/Ob group (leptin: P<0.001; insulin: P<0.03). HM insulin was 98% higher than maternal plasma insulin at 2-weeks and 32% higher at 4-months (P<0.001). Maternal fasting plasma insulin and HOMA-IR were positively related to HM insulin at 2-weeks (P<0.001, R 2 ⩾0.38, n=31), and 4-months (P⩽0.005, R 2 ⩾0.20, n=38). The concentrations of insulin in HM are higher than in maternal plasma and are related to maternal BMI and insulin sensitivity. With the exception of leptin, there were minimal other differences observed in HM composition across a wide range in maternal BMI.

A membrane basis for bacterial identification and discrimination using laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Rehse, Steven J.; Jeyasingham, Narmatha; Diedrich, Jonathan; Palchaudhuri, Sunil

2009-05-01

Nanosecond single-pulse laser-induced breakdown spectroscopy (LIBS) has been used to discriminate between two different genera of Gram-negative bacteria and between several strains of the Escherichia coli bacterium based on the relative concentration of trace inorganic elements in the bacteria. Of particular importance in all such studies to date has been the role of divalent cations, specifically Ca2+ and Mg2+, which are present in the membranes of Gram-negative bacteria and act to aggregate the highly polar lipopolysaccharide molecules. We have demonstrated that the source of emission from Ca and Mg atoms observed in LIBS plasmas from bacteria is at least partially located at the outer membrane by intentionally altering membrane biochemistry and correlating these changes with the observed changes in the LIBS spectra. The definitive assignment of some fraction of the LIBS emission to the outer membrane composition establishes a potential serological, or surface-antigen, basis for the laser-based identification. E. coli and Pseudomonas aeruginosa were cultured in three nutrient media: trypticase soy agar as a control, a MacConkey agar with a 0.01% concentration of bile salts including sodium deoxycholate, and a trypticase soy agar with a 0.4% deoxycholate concentration. The higher concentration of deoxycholate is known to disrupt bacterial outer membrane integrity and was expected to induce changes in the observed LIBS spectra. Altered LIBS emission was observed for bacteria cultured in this 0.4% medium and laser ablated in an all-argon environment. These spectra evidenced a reduced calcium emission and in the case of one species, a reduced magnesium emission. Culturing on the lower (0.01%) concentration of bile salts altered the LIBS spectra for both the P. aeruginosa and two strains of E. coli in a highly reproducible way, although not nearly as significantly as culturing in the higher concentration of deoxycholate did. This was possibly due to the accumulation of divalent cations around the bacteria by the formation of an extracellular polysaccharide capsule. Lastly, a discriminant function analysis demonstrated that in spite of alterations in the LIBS spectrum induced by growth in the three different media, the analysis could correctly identify all samples better than 90% of the time. This encouraging result illustrates the potential utility of LIBS as a rapid bacteriological identification technology.

[Impact of Land Utilization Pattern on Distributing Characters of Labile Organic Carbon in Soil Aggregates in Jinyun Mountain].

PubMed

Li, Rui; Jiang, Chang-sheng; Hao, Qing-ju

2015-09-01

Four land utilization patterns were selected for this study in Jinyun mountain, including subtropical evergreen broad-leaved forest (abbreviation: forest), sloping farmland, orchard and abandoned land. Soil samples were taken every 10 cm in the depth of 60 cm soil and proportions of large macroaggregates (> 2 mm), small macroaggregates (0. 25-2 mm), microaggregates (0. 053 - 0. 25 mm) and silt + clay (<0. 053 mm) were obtained by wet sieving method to measure the content of organic carbon and labile organic carbon in each aggregate fraction and analyze impacts of land uses on organic carbon and labile organic carbon of soil aggregates. LOC content of four soil aggregates were significantly reduced with the increase of soil depth; in layers of 0-60 cm soil depth, our results showed that LOC contents of forest and abandoned land were higher than orchard and sloping farmland. Reserves of labile organic carbon were estimated by the same soil quality, it revealed that forest (3. 68 Mg.hm-2) > abandoned land (1. 73 Mg.hm-2) > orchard (1. 43 Mg.hm-2) >sloping farmland (0.54 Mg.hm-2) in large macroaggregates, abandoned land (7.77, 5. 01 Mg.hm-2) > forest (4. 96, 2.71 Mg.hm-2) > orchard (3. 33, 21. 10 Mg.hm-2) > sloping farmland (1. 68, 1. 35 Mg.hm-2) in small macroaggregates and microaggregates, and abandoned land(4. 32 Mg.hm-2) > orchard(4. 00 Mg.hm-2) > forest(3. 22 Mg.hm-2) > sloping farmland (2.37 Mg.hm-2) in silt + clay, forest and abandoned land were higher than orchard and sloping farmland in other three soil aggregates except silt + clay. It was observed that the level of organic carbon and labile organic carbon were decreased when bringing forest under cultivation to orchard or farmland, and augments on organic carbon and labile organic carbon were found after exchanging farmland to abandoned land. The most reverses of forest and abandoned land emerged in small macroaggregates, orchard and sloping farmland were in microaggregates. That was, during the transformations of land utilization pattern, soil aggregates with bigger size were easier to accumulate or lose labile organic carbon. Allocation ratios of labile organic carbon to soil organic carbon under four land uses were decreased as the soil depth added. Allocation ratios of orchard and sloping farmland were a bit higher than forest and abandoned land, which indicated that organic carbon of forest and abandoned land were more steady and available for soil as a carbon sink, meanwhile, the forest and abandoned land would avoid more CO2 diffusing to the atmosphere from the decomposition of soil organic carbon.

Testing a laser-induced breakdown spectroscopy technique on the Arctic sediments

NASA Astrophysics Data System (ADS)

Han, D.; Nam, S. I.

2017-12-01

Physical and geochemical investigations coupled with the Laser-induced Breakdown Spectroscopy (LIBS) were performed on three surface sediment cores (ARA03B/24BOX, ARA02B/01(A)MUC, ARA02B/02MUC and ARA02B/03(A)MUC) recovered from the western Arctic Ocean (Chukchi Sea) during IBRV ARON expeditions in 2012. The LIBS technique was applied to carry out elemental chemical analysis of the Arctic sediments and compared with that measured by ITRAX X-ray fuorescence (XRF) core scanning. LIBS and XRF have shown similar elemental composition within each sediment core. In this study, mineral composition (XRD), grain size distribution and organic carbon content as well as elemental composition (LIBS) were all considered to understand paleoenvironmental changes (ocean circulation, sea-ice drift, iceberg discharge, and etc.) recorded in the Arctic Holocene sediment. Quantitative LIBS analysis shows a gradually varying distribution of the elements along the sampled core and clear separation between the cores. The cores are geochemically characterized by elevated Mn profile. The gradient of mineral composition and grain sizes among the cores shows regional distribution and variation in sedimentary condition due to geological distance between East Siberian and North America. The present study reveals that a LIBS technique can be employed for in-situ sediment analyses for the Arctic Ocean. Furthermore, LIBS does not require costly equipment, trained operators, and complicated sample pre-treatment processes compared to Atomic absorption spectroscopy (AAS) and inductively coupled plasma emission spectroscopy (ICP), and also known to show relatively high levels of sensitivity, precision, and distinction than XRF analysis, scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), and electron probe X-ray microanalysis (EPMA).

LIBS: a new versatile field-deployable real-time detector system with potential for landmine detection

NASA Astrophysics Data System (ADS)

Harmon, Russell S.; De Lucia, Frank C.; Winkel, Raymond J., Jr.; LaPointe, Aaron; Grossman, Scott L.; McNesby, Kevin L.; Miziolek, Andrzej W.

2003-09-01

Laser Induced Breakdown Spectroscopy (LIBS) is an atomic emission spectroscopic technique that utilizes a pulsed laser to create a microplasma on the target together with an array spectrometer to capture the transient light for elemental identification and quantification. LIBS has certain important characteristics that make it a very attractive sensor technology for military uses. Such attributes include that facts that LIBS (1) is relatively simple and straightforward, (2) requires no sample preparation, (3) generates a real-time response, and (4) only engages a very small sample (pg-ng) of matter in each laser shot and microplasma event, (5) has inherent high sensitivity, and (6) responds to all forms of unknowns, and, therefore, is particularly suited for the sensing of dangerous materials. Additionally, a LIBS sensor system can be inexpensive, configured to be man-portable, and designed for both in-situ point sensing and remote stand-off detection with distances of up to 20-25 meters. Broadband LIBS results covering the spectral region from 200-970 nm acquired at the Army Research Laboratory (ARL) under laboratory conditions for a variety of landmine casings and explosive materials. This data will illustrate the potential that LIBS has to be developed into a hand-deployable device that could be utilized as a confirmatory sensor in landmine detection. The concept envisioned is a backpack-size system in which an eyesafe micro-laser is contained in the handle of a deminer's probe and light is delivered and collected through an optical fiber in the tapered tip of the probe. In such a configuration, analyses can be made readily by touching the buried object that one is interested in identifying.

libChEBI: an API for accessing the ChEBI database.

PubMed

Swainston, Neil; Hastings, Janna; Dekker, Adriano; Muthukrishnan, Venkatesh; May, John; Steinbeck, Christoph; Mendes, Pedro

2016-01-01

ChEBI is a database and ontology of chemical entities of biological interest. It is widely used as a source of identifiers to facilitate unambiguous reference to chemical entities within biological models, databases, ontologies and literature. ChEBI contains a wealth of chemical data, covering over 46,500 distinct chemical entities, and related data such as chemical formula, charge, molecular mass, structure, synonyms and links to external databases. Furthermore, ChEBI is an ontology, and thus provides meaningful links between chemical entities. Unlike many other resources, ChEBI is fully human-curated, providing a reliable, non-redundant collection of chemical entities and related data. While ChEBI is supported by a web service for programmatic access and a number of download files, it does not have an API library to facilitate the use of ChEBI and its data in cheminformatics software. To provide this missing functionality, libChEBI, a comprehensive API library for accessing ChEBI data, is introduced. libChEBI is available in Java, Python and MATLAB versions from http://github.com/libChEBI, and provides full programmatic access to all data held within the ChEBI database through a simple and documented API. libChEBI is reliant upon the (automated) download and regular update of flat files that are held locally. As such, libChEBI can be embedded in both on- and off-line software applications. libChEBI allows better support of ChEBI and its data in the development of new cheminformatics software. Covering three key programming languages, it allows for the entirety of the ChEBI database to be accessed easily and quickly through a simple API. All code is open access and freely available.

Incorporation of support vector machines in the LIBS toolbox for sensitive and robust classification amidst unexpected sample and system variability

PubMed Central

ChariDingari, Narahara; Barman, Ishan; Myakalwar, Ashwin Kumar; Tewari, Surya P.; Kumar, G. Manoj

2012-01-01

Despite the intrinsic elemental analysis capability and lack of sample preparation requirements, laser-induced breakdown spectroscopy (LIBS) has not been extensively used for real world applications, e.g. quality assurance and process monitoring. Specifically, variability in sample, system and experimental parameters in LIBS studies present a substantive hurdle for robust classification, even when standard multivariate chemometric techniques are used for analysis. Considering pharmaceutical sample investigation as an example, we propose the use of support vector machines (SVM) as a non-linear classification method over conventional linear techniques such as soft independent modeling of class analogy (SIMCA) and partial least-squares discriminant analysis (PLS-DA) for discrimination based on LIBS measurements. Using over-the-counter pharmaceutical samples, we demonstrate that application of SVM enables statistically significant improvements in prospective classification accuracy (sensitivity), due to its ability to address variability in LIBS sample ablation and plasma self-absorption behavior. Furthermore, our results reveal that SVM provides nearly 10% improvement in correct allocation rate and a concomitant reduction in misclassification rates of 75% (cf. PLS-DA) and 80% (cf. SIMCA)-when measurements from samples not included in the training set are incorporated in the test data – highlighting its robustness. While further studies on a wider matrix of sample types performed using different LIBS systems is needed to fully characterize the capability of SVM to provide superior predictions, we anticipate that the improved sensitivity and robustness observed here will facilitate application of the proposed LIBS-SVM toolbox for screening drugs and detecting counterfeit samples as well as in related areas of forensic and biological sample analysis. PMID:22292496

[Element distribution analysis of welded fusion zone by laser-induced breakdown spectroscopy].

PubMed

Yang, Chun; Zhang, Yong; Jia, Yun-Hai; Wang, Hai-Zhou

2014-04-01

Over the past decade there has been intense activity in the study and development of laser-induced breakdown spectroscopy (LIBS). As a new tool for surface microanalysis, it caused widespread in materials science because of the advantage of rapid and high sensitivity. In the present paper, the distribution of Ni, Mn, C and Si near weld fusion line was analyzed on two kinds of weld sample. Line scanning mode analysis was carried out by three different kinds of methods, namely laser-induced breakdown spectroscopy (LIBS), scanning electron microscope/energy dispersive spectrometer (SEM/EDS) and electron probe X-ray microanalyser (EPMA). The concentration variation trend of Ni and Mn acquired by LIBS is coincident with SEM/EDS and EPMA. The result shows that the content of Ni and Mn was significantly different between weld seam and base metal on both the samples. The content of Ni and Mn was much higher in weld seam than in base metal, and a sharp concentration gradient was analyzed in the fusion zone. According to the distribution of Ni and Mn, all the three methods got a similar value of welded fusion zone width. The concentration variation trend of C and Si acquired by LIBS is not coincident with SEM/EDS and EPMA. The concentration difference between weld seam and base metal was analyzed by LIBS, but had not by SEM/EDS and EPMA, because of the low concentration and slight difference. The concentration gradient of C and Si in fusion zone was shows clearly by LIBS. For higher sensitivity performance, LIBS is much more adapted to analyze low content element than SEM/EDS and EPMA.

Qualitative and quantitative analysis of human nails to find correlation between nutrients and vitamin D deficiency using LIBS and ICP-AES.

PubMed

Almessiere, M A; Altuwiriqi, R; Gondal, M A; AlDakheel, R K; Alotaibi, H F

2018-08-01

In this work, we analysed human fingernails of people who suffer from vitamin D deficiency using the laser-induced breakdown spectroscopy(LIBS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES)techniques. The measurements have been conducted on 71 nail samples collected randomly from volunteers of different genders and ages ranged between 20 and 50 years. The main aim of this study is to find the correlation between vitamin D deficiency and the intensity of some dominated lines in the LIBS spectra. A LIBS spectrum consists of dominant lines of fifteen elements including calcium, magnesium, sodium, potassium, titanium, iron, chloride, sulphur, copper, chromium, zinc, nitrogen, phosphor, and oxygen. By recording the spectrum in specific ranges and focusing on calcium, magnesium, sodium, and potassium, we found a correlation between the intensity of the potassium (K) lines at (766.5 and 769.9 nm)and vitamin D level in both age groups (20 and 25 years old), with weak correlation for the calcium (Ca), magnesium (Mg), and sodium (Na) lines. To verify the validity of the LIBS results, we analysed the nail samples with ICP, a standard analytical technique. The elements detected with our LIBS technique are in a good agreement with those identified by ICP-AES. From the health and physiological perspectives, the LIBS system, which is used for spectral analysis in this work, is appropriate for diagnostic purposes such as to find the correlation between vitamin D deficiency and potassium content, especially for hypertensive patients who simultaneously take potassium-based medication and vitamin D supplement. Copyright © 2018 Elsevier B.V. All rights reserved.

Incorporation of support vector machines in the LIBS toolbox for sensitive and robust classification amidst unexpected sample and system variability.

PubMed

Dingari, Narahara Chari; Barman, Ishan; Myakalwar, Ashwin Kumar; Tewari, Surya P; Kumar Gundawar, Manoj

2012-03-20

Despite the intrinsic elemental analysis capability and lack of sample preparation requirements, laser-induced breakdown spectroscopy (LIBS) has not been extensively used for real-world applications, e.g., quality assurance and process monitoring. Specifically, variability in sample, system, and experimental parameters in LIBS studies present a substantive hurdle for robust classification, even when standard multivariate chemometric techniques are used for analysis. Considering pharmaceutical sample investigation as an example, we propose the use of support vector machines (SVM) as a nonlinear classification method over conventional linear techniques such as soft independent modeling of class analogy (SIMCA) and partial least-squares discriminant analysis (PLS-DA) for discrimination based on LIBS measurements. Using over-the-counter pharmaceutical samples, we demonstrate that the application of SVM enables statistically significant improvements in prospective classification accuracy (sensitivity), because of its ability to address variability in LIBS sample ablation and plasma self-absorption behavior. Furthermore, our results reveal that SVM provides nearly 10% improvement in correct allocation rate and a concomitant reduction in misclassification rates of 75% (cf. PLS-DA) and 80% (cf. SIMCA)-when measurements from samples not included in the training set are incorporated in the test data-highlighting its robustness. While further studies on a wider matrix of sample types performed using different LIBS systems is needed to fully characterize the capability of SVM to provide superior predictions, we anticipate that the improved sensitivity and robustness observed here will facilitate application of the proposed LIBS-SVM toolbox for screening drugs and detecting counterfeit samples, as well as in related areas of forensic and biological sample analysis.

Simulated In Situ Determination of Soil Profile Organic and Inorganic Carbon With LIBS and VisNIR

NASA Astrophysics Data System (ADS)

Bricklemyer, R. S.; Brown, D. J.; Clegg, S. M.; Barefield, J. E.

2008-12-01

There is growing need for rapid, accurate, and inexpensive methods to measure, and verify soil organic carbon (SOC) change for national greenhouse gas accounting and the development of a soil carbon trading market. Laser Induced Breakdown Spectroscopy (LIBS) and Visible and Near Infrared Spectroscopy (VisNIR) are complementary analytical techniques that have the potential to fill that need. The LIBS method provides precise elemental analysis of soils, but generally cannot distinguish between organic C and inorganic C. VisNIR has been established as a viable technique for measuring soil properties including SOC and inorganic carbon (IC). As part of the Big Sky Carbon Sequestration Regional Partnership, 240 intact core samples (3.8 x 50 cm) have been collected from six agricultural fields in north central Montana, USA. Each of these core samples were probed concurrently with LIBS and VisNIR at 2.5, 7.5, 12.5, 17.5, 22.5, 27.5, 35 and 45 cm (+/- 1.5 cm) depths. VisNIR measurements were taken using an Analytical Spectral Devices (ASD, Boulder, CO, USA) Agrispec spectrometer to determine the partition of SOC vs. IC in the samples. The LIBS scans were collected with the LANL LIBS Core Scanner Instrument which collected the entire 200 - 900 nm plasma emission including the 247.8 nm carbon emission line. This instrument also collected the emission from the elements typically found in inorganic carbon (Ca and Mg) and organic carbon (H, O, and N). Subsamples of soil (~ 4 g) were taken from interrogation points for laboratory determination of SOC and IC. Using this analytical data, we constructed several full spectrum multivariate VisNIR/LIBS calibration models for SOC and IC. These models were then applied to independent validation cores for model evaluation.

Quantification of trace metals in infant formula premixes using laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Cama-Moncunill, Raquel; Casado-Gavalda, Maria P.; Cama-Moncunill, Xavier; Markiewicz-Keszycka, Maria; Dixit, Yash; Cullen, Patrick J.; Sullivan, Carl

2017-09-01

Infant formula is a human milk substitute generally based upon fortified cow milk components. In order to mimic the composition of breast milk, trace elements such as copper, iron and zinc are usually added in a single operation using a premix. The correct addition of premixes must be verified to ensure that the target levels in infant formulae are achieved. In this study, a laser-induced breakdown spectroscopy (LIBS) system was assessed as a fast validation tool for trace element premixes. LIBS is a promising emission spectroscopic technique for elemental analysis, which offers real-time analyses, little to no sample preparation and ease of use. LIBS was employed for copper and iron determinations of premix samples ranging approximately from 0 to 120 mg/kg Cu/1640 mg/kg Fe. LIBS spectra are affected by several parameters, hindering subsequent quantitative analyses. This work aimed at testing three matrix-matched calibration approaches (simple-linear regression, multi-linear regression and partial least squares regression (PLS)) as means for precision and accuracy enhancement of LIBS quantitative analysis. All calibration models were first developed using a training set and then validated with an independent test set. PLS yielded the best results. For instance, the PLS model for copper provided a coefficient of determination (R2) of 0.995 and a root mean square error of prediction (RMSEP) of 14 mg/kg. Furthermore, LIBS was employed to penetrate through the samples by repetitively measuring the same spot. Consequently, LIBS spectra can be obtained as a function of sample layers. This information was used to explore whether measuring deeper into the sample could reduce possible surface-contaminant effects and provide better quantifications.

An Evaluation of Femtosecond/nanosecond Laser Induced Breakdown Spectroscopy (LIBS) for Measuring Total Particulate Emissions

DTIC Science & Technology

2009-05-07

would discourage the use of LIBS for distinguishing between gaseous and particulate species; however, recent studies by Prof. David Hahn at the...If a concept proved feasible, then it would be evaluated in more realistic environments. The program involved a joint effort between Prof. David ...multiphase ns-LIBS measurement that are most relevant to this study are illustrated in the research performed by Prof. David Hahn at the University of Florida

Ramus marginalis mandibulae nervus facialis palsy in hemifacial microsomia.

PubMed

Silvestri, A; Mariani, G; Vernucci, R A

2008-12-01

The paralysis of the ramus marginalis mandibulae nervus facialis may occur in Hemifacial Microsomia (HM); the combination of both HM and palsy contributes to an elongation of the mandibular body. This study explores a possible correlation between neurological deficit, muscular atony, and structural deficiency. Of 58 patients with HM who had come to the University of Rome (Sapienza) Pre-surgical Orthodontics Unit, 4 patients were afflicted with Hemifacial Microsomia and ramus marginalis mandibulae nervus palsy; these patients underwent physical, neurological, opthamologic and systemic examinations. The results were then analysed in order to determine a possible correlation between neuro-muscular and structural deficit. Electroneurographic and electromyographic examinations were performed to estimate facial nerve and muscles involvement. Neuroelectrographic exam showed a damage of the nervous motor fibres of the facial nerve ipsilateral to HM, with an associated damage of the muscular function, while neuro-muscular functions on the healthy side were normal. The peripheral nervous and muscular deficits affect the function of facial soft tissues and the growth of mandibular body with an asymmetry characterised by a hypodevelopment of the ramus (due to the HM) and by an elongation of the mandibular body (due to ramus marginalis mandibulae nerve palsy), so that the chin deviation is contralateral to HM. In these forms, a neurological examination is necessary to assess the neurological damage on the HM side. Neuromuscular deficiency can also contribute to a relapse tendency after a surgical-orthodontic treatment.

Canine Histiocytic Malignancies—Challenges and Opportunities

PubMed Central

Kennedy, Katherine; Thomas, Rachael; Breen, Matthew

2016-01-01

Canine histiocytic malignancies (HM) are aggressive tumors that occur with particularly high frequency in certain breeds including Bernese mountain dogs and flat-coated retrievers. Robust diagnosis of HM commonly utilizes immunohistochemical stains that are broadly ineffective on formalin-fixed tissues; thus the diagnosis is often one of exclusion. Clinical outcomes are generally poor, with frequent metastasis and therapeutic failure lowering overall survival at time of diagnosis to an average of less than two months in the majority of published work. The limited understanding of the molecular mechanisms underlying HM has hindered the development of more effective diagnostic modalities and the identification of therapeutic targets. A potential avenue exists for advancing clinical management of canine cancers through extrapolation from a close counterpart in human medicine. Historically, HM have been compared to the rare and understudied subset of human cancers involving the dendritic lineage, such as dendritic cell sarcoma or Langerhans cell sarcoma. Recent data have now thrown into question the cellular origin of HM, suggesting that the disease may originate from the macrophage lineage. This review summarizes existing knowledge of HM from the clinical, histologic and molecular perspectives, and highlights avenues for future research that may aid the development of novel diagnostic and therapeutic approaches. In turn, a more advanced appreciation of the mechanisms underlying HM should clarify their cellular origin and identify appropriate opportunities for synergistic extrapolation between related canine and human cancers. PMID:29056712

Human Milk Fatty Acid Composition: Comparison of Novel Dried Milk Spot Versus Standard Liquid Extraction Methods.

PubMed

Rudolph, Michael C; Young, Bridget E; Jackson, Kristina Harris; Krebs, Nancy F; Harris, William S; MacLean, Paul S

2016-12-01

Accurate assessment of the long chain polyunsaturated fatty acid (LC-PUFA) content of human milk (HM) provides a powerful means to evaluate the FA nutrient status of breastfed infants. The conventional standard for FA composition analysis of HM is liquid extraction, trans-methylation, and analyte detection resolved by gas chromatography. This standard approach requires fresh or frozen samples, storage in deep freeze, organic solvents, and specialized equipment in processing and analysis. Further, HM collection is often impractical for many studies in the free living environment, particularly for studies in developing countries. In the present study, we compare a novel and more practical approach to sample collection and processing that involves the spotting and drying ~50 μL of HM on a specialized paper stored and transported at ambient temperatures until analysis. Deming regression indicated the two methods aligned very well for all LC-PUFA and the abundant HM FA. Additionally, strong correlations (r > 0.85) were observed for DHA, ARA, EPA, linoleic (LA), and alpha-linolenic acids (ALA), which are of particular interest to the health of the developing infant. Taken together, our data suggest this more practical and inexpensive method of collection, storage, and transport of HM milk samples could dramatically facilitate studies of HM, as well as understanding its lipid composition influences on human health and development.

Paraneoplastic hypercalcemia.

PubMed

Bergman, Philip J

2012-11-01

Paraneoplastic syndromes (PNSs) are neoplasm-associated alterations in bodily structure or function or both that occur distant to the tumor. They are an extremely diverse group of clinical aberrations that are associated with the noninvasive actions of the tumor. In many situations, the PNS parallels the underlying malignancy, and therefore, successful treatment of the tumor leads to disappearance of the PNS. Alternatively, recurrence of the PNS after successful treatment signals recurrence of the tumor, and the return of the PNS often significantly precedes the detectable recurrence of the tumor. This is often the case with paraneoplastic hypercalcemia, often referred to as hypercalcemia of malignancy (HM). The most common cause of hypercalcemia in dogs is cancer. Neoplasia is diagnosed in approximately two-thirds of dogs with hypercalcemia vs. approximately one-third in cats. A variety of tumors have been associated with HM. Lymphoma is the most common cause of HM, and the most common anatomical site for dogs with lymphoma-associated HM is the cranial mediastinum. Other tumors associated with HM in dogs and cats include anal sac apocrine gland adenocarcinoma, thyroid carcinoma, multiple myeloma, bone tumors, thymoma, squamous cell carcinoma, mammary gland carcinoma/adenocarcinoma, melanoma, primary lung tumors, chronic lymphocytic leukemia, renal angiomyxoma, and parathyroid gland tumors. As HM is a potential medical emergency, the primary goal in cases of HM is the elucidation of the underlying cause and thereby instituting the appropriate specific therapy. Copyright © 2012 Elsevier Inc. All rights reserved.

1H NMR studies of the 5-(hydroxymethyl)-2'-deoxyuridine containing TF1 binding site.

PubMed

Pasternack, L B; Bramham, J; Mayol, L; Galeone, A; Jia, X; Kearns, D R

1996-07-15

The pyrimidine base 5-(hydroxymethyl)-2'-deoxyuridine (HmU) is a common nucleotide in SPO1 phage DNA. Numerous transcriptional proteins bind HmU-containing DNA preferentially implicating a regulatory function of HmU. We have investigated the conformation and dynamics of d-(5'-CHmUCHmUACACGHmUGHmUAGAG-OH-3')2 (HmU-DNA). This oligonucleotide mimics the consensus sequence of Transcription Factor 1 (TF1). The HmU-DNA was compared to the thymine-containing oligonucleotide. NOESY and DQF COSY spectroscopy provided resonance assignments of nonexchangeable and exchangeable protons, intranucleotide, internucleotide and intrastrand proton-proton distances, and dihedral angle constraints. Methylene protons of the hydroxymethyl group are nonequivalent protons and the hydroxymethyl group is not freely rotating. The hydroxymethyl group adopts a specific orientation with the OH group oriented on the 3' side of the plane of the base. Analysis of imino proton resonances and NOEs indicates additional end base pair fraying and a temperature-induced transition to a conformation in which the internal HmU-A base pairs are disrupted or have reduced lifetimes. Orientation of the hydroxymethyl group indicates the presence of internucleotide intrastrand hydrogen bonding between the HmU12C5 hydroxyl group and A13. All sugars in both DNAs show a C2'endo conformation (typical of B-DNA).

Inverse Calibration Free fs-LIBS of Copper-Based Alloys

NASA Astrophysics Data System (ADS)

Smaldone, Antonella; De Bonis, Angela; Galasso, Agostino; Guarnaccio, Ambra; Santagata, Antonio; Teghil, Roberto

2016-09-01

In this work the analysis by Laser Induced Breakdown Spectroscopy (LIBS) technique of copper-based alloys having different composition and performed with fs laser pulses is presented. A Nd:Glass laser (Twinkle Light Conversion, λ = 527 nm at 250 fs) and a set of bronze and brass certified standards were used. The inverse Calibration-Free method (inverse CF-LIBS) was applied for estimating the temperature of the fs laser induced plasma in order to achieve quantitative elemental analysis of such materials. This approach strengthens the hypothesis that, through the assessment of the plasma temperature occurring in fs-LIBS, straightforward and reliable analytical data can be provided. With this aim the capability of the here adopted inverse CF-LIBS method, which is based on the fulfilment of the Local Thermodynamic Equilibrium (LTE) condition, for an indirect determination of the species excitation temperature, is shown. It is reported that the estimated temperatures occurring during the process provide a good figure of merit between the certified and the experimentally determined composition of the bronze and brass materials, here employed, although further correction procedure, like the use of calibration curves, can be demanded. The reported results demonstrate that the inverse CF-LIBS method can be applied when fs laser pulses are used even though the plasma properties could be affected by the matrix effects restricting its full employment to unknown samples provided that a certified standard having similar composition is available.

A Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) Quantitative Analysis Method Based on the Auto-Selection of an Internal Reference Line and Optimized Estimation of Plasma Temperature.

PubMed

Yang, Jianhong; Li, Xiaomeng; Xu, Jinwu; Ma, Xianghong

2018-01-01

The quantitative analysis accuracy of calibration-free laser-induced breakdown spectroscopy (CF-LIBS) is severely affected by the self-absorption effect and estimation of plasma temperature. Herein, a CF-LIBS quantitative analysis method based on the auto-selection of internal reference line and the optimized estimation of plasma temperature is proposed. The internal reference line of each species is automatically selected from analytical lines by a programmable procedure through easily accessible parameters. Furthermore, the self-absorption effect of the internal reference line is considered during the correction procedure. To improve the analysis accuracy of CF-LIBS, the particle swarm optimization (PSO) algorithm is introduced to estimate the plasma temperature based on the calculation results from the Boltzmann plot. Thereafter, the species concentrations of a sample can be calculated according to the classical CF-LIBS method. A total of 15 certified alloy steel standard samples of known compositions and elemental weight percentages were used in the experiment. Using the proposed method, the average relative errors of Cr, Ni, and Fe calculated concentrations were 4.40%, 6.81%, and 2.29%, respectively. The quantitative results demonstrated an improvement compared with the classical CF-LIBS method and the promising potential of in situ and real-time application.

Detection of carcinogenic metals in kidney stones using ultraviolet laser-induced breakdown spectroscopy.

PubMed

Khalil, Ahmed Asaad I; Gondal, Mohammed A; Shemis, Mohamed; Khan, Irfan S

2015-03-10

The UV single-pulsed (SP) laser-induced breakdown spectroscopy (LIBS) system was developed to detect the carcinogenic metals in human kidney stones extracted through the surgical operation. A neodymium yttrium aluminium garnet laser operating at 266 nm wavelength and 20 Hz repetition rate along with a spectrometer interfaced with an intensified CCD (ICCD) was applied for spectral analysis of kidney stones. The ICCD camera shutter was synchronized with the laser-trigger pulse and the effect of laser energy and delay time on LIBS signal intensity was investigated. The experimental parameters were optimized to obtain the LIBS plasma in local thermodynamic equilibrium. Laser energy was varied from 25 to 50 mJ in order to enhance the LIBS signal intensity and attain the best signal to noise ratio. The parametric dependence studies were important to improve the limit of detection of trace amounts of toxic elements present inside stones. The carcinogenic metals detected in kidney stones were chromium, cadmium, lead, zinc, phosphate, and vanadium. The results achieved from LIBS system were also compared with the inductively coupled plasma-mass spectrometry analysis and the concentration detected with both techniques was in very good agreement. The plasma parameters (electron temperature and density) for SP-LIBS system were also studied and their dependence on incident laser energy and delay time was investigated as well.

LibIsopach

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

Brunhart-Lupo, Nicholas

2016-12-06

LibIsopach is a toolkit for high performance distributed immersive visualization, leveraging modern OpenGL. It features a multi-process scenegraph, explicit instance rendering, mesh generation, and three-dimensional user interaction event processing.

Multivariate classification of edible salts: Simultaneous Laser-Induced Breakdown Spectroscopy and Laser-Ablation Inductively Coupled Plasma Mass Spectrometry Analysis

NASA Astrophysics Data System (ADS)

Lee, Yonghoon; Nam, Sang-Ho; Ham, Kyung-Sik; Gonzalez, Jhanis; Oropeza, Dayana; Quarles, Derrick; Yoo, Jonghyun; Russo, Richard E.

2016-04-01

Laser-Induced Breakdown Spectroscopy (LIBS) and Laser-Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS), both based on laser ablation sampling, can be employed simultaneously to obtain different chemical fingerprints from a sample. We demonstrated that this analysis approach can provide complementary information for improved classification of edible salts. LIBS could detect several of the minor metallic elements along with Na and Cl, while LA-ICP-MS spectra were used to measure non-metallic and trace heavy metal elements. Principal component analysis using LIBS and LA-ICP-MS spectra showed that their major spectral variations classified the sample salts in different ways. Three classification models were developed by using partial least squares-discriminant analysis based on the LIBS, LA-ICP-MS, and their fused data. From the cross-validation performances and confusion matrices of these models, the minor metallic elements (Mg, Ca, and K) detected by LIBS and the non-metallic (I) and trace heavy metal (Ba, W, and Pb) elements detected by LA-ICP-MS provided complementary chemical information to distinguish particular salt samples.

StrBioLib: a Java library for development of custom computationalstructural biology applications

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

Chandonia, John-Marc

2007-05-14

Summary: StrBioLib is a library of Java classes useful fordeveloping software for computational structural biology research.StrBioLib contains classes to represent and manipulate proteinstructures, biopolymer sequences, sets of biopolymer sequences, andalignments between biopolymers based on either sequence or structure.Interfaces are provided to interact with commonly used bioinformaticsapplications, including (PSI)-BLAST, MODELLER, MUSCLE, and Primer3, andtools are provided to read and write many file formats used to representbioinformatic data. The library includes a general-purpose neural networkobject with multiple training algorithms, the Hooke and Jeeves nonlinearoptimization algorithm, and tools for efficient C-style string parsingand formatting. StrBioLib is the basis for the Pred2ary secondarystructure predictionmore » program, is used to build the ASTRAL compendium forsequence and structure analysis, and has been extensively tested throughuse in many smaller projects. Examples and documentation are available atthe site below.Availability: StrBioLib may be obtained under the terms ofthe GNU LGPL license from http://strbio.sourceforge.net/Contact:JMChandonia@lbl.gov« less

Fire debris analysis for forensic fire investigation using laser induced breakdown spectroscopy (LIBS)

NASA Astrophysics Data System (ADS)

Choi, Soojin; Yoh, Jack J.

2017-08-01

The possibility verification of the first attempt to apply LIBS to arson investigation was performed. LIBS has capabilities for real time in-situ analysis and depth profiling. It can provide valuable information about the fire debris that are complementary to the classification of original sample components and combustion residues. In this study, fire debris was analyzed to determine the ignition source and existence of a fire accelerant using LIBS spectra and depth profiling analysis. Fire debris chemical composition and carbon layer thickness determines the possible ignition source while the carbon layer thickness of combusted samples represents the degree of sample carbonization. When a sample is combusted with fire accelerants, a thicker carbon layer is formed because the burning rate is increased. Therefore, depth profiling can confirm the existence of combustion accelerants, which is evidence of arson. Also investigation of fire debris by depth profiling is still possible when a fire is extinguished with water from fire hose. Such data analysis and in-situ detection of forensic signals via the LIBS may assist fire investigation at crime scenes.

StrBioLib: a Java library for development of custom computational structural biology applications.

PubMed

Chandonia, John-Marc

2007-08-01

StrBioLib is a library of Java classes useful for developing software for computational structural biology research. StrBioLib contains classes to represent and manipulate protein structures, biopolymer sequences, sets of biopolymer sequences, and alignments between biopolymers based on either sequence or structure. Interfaces are provided to interact with commonly used bioinformatics applications, including (psi)-blast, modeller, muscle and Primer3, and tools are provided to read and write many file formats used to represent bioinformatic data. The library includes a general-purpose neural network object with multiple training algorithms, the Hooke and Jeeves non-linear optimization algorithm, and tools for efficient C-style string parsing and formatting. StrBioLib is the basis for the Pred2ary secondary structure prediction program, is used to build the astral compendium for sequence and structure analysis, and has been extensively tested through use in many smaller projects. Examples and documentation are available at the site below. StrBioLib may be obtained under the terms of the GNU LGPL license from http://strbio.sourceforge.net/

Elemental analysis of cotton by laser-induced breakdown spectroscopy

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

Schenk, Emily R.; Almirall, Jose R.

Laser-induced breakdown spectroscopy (LIBS) has been applied to the elemental characterization of unprocessed cotton. This research is important in forensic and fraud detection applications to establish an elemental fingerprint of U.S. cotton by region, which can be used to determine the source of the cotton. To the best of our knowledge, this is the first report of a LIBS method for the elemental analysis of cotton. The experimental setup consists of a Nd:YAG laser that operates at the fundamental wavelength as the LIBS excitation source and an echelle spectrometer equipped with an intensified CCD camera. The relative concentrations of elementsmore » Al, Ba, Ca, Cr, Cu, Fe, Mg, and Sr from both nutrients and environmental contributions were determined by LIBS. Principal component analysis was used to visualize the differences between cotton samples based on the elemental composition by region in the U.S. Linear discriminant analysis of the LIBS data resulted in the correct classification of >97% of the cotton samples by U.S. region and >81% correct classification by state of origin.« less

Intercalated Water and Organic Molecules for Electrode Materials of Rechargeable Batteries.

PubMed

Lee, Hyeon Jeong; Shin, Jaeho; Choi, Jang Wook

2018-03-24

The intrinsic limitations of lithium-ion batteries (LIBs) with regard to safety, cost, and the availability of raw materials have promoted research on so-called "post-LIBs". The recent intense research of post-LIBs provides an invaluable lesson that existing electrode materials used in LIBs may not perform as well in post-LIBs, calling for new material designs compliant with emerging batteries based on new chemistries. One promising approach in this direction is the development of materials with intercalated water or organic molecules, as these materials demonstrate superior electrochemical performance in emerging battery systems. The enlarged ionic channel dimensions and effective shielding of the electrostatic interaction between carrier ions and the lattice host are the origins of the observed electrochemical performance. Moreover, these intercalants serve as interlayer pillars to sustain the framework for prolonged cycles. Representative examples of such intercalated materials applied to batteries based on Li + , Na + , Mg 2+ , and Zn 2+ ions and supercapacitors are considered, along with their impact in materials research. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Multivariate calibration in Laser-Induced Breakdown Spectroscopy quantitative analysis: The dangers of a 'black box' approach and how to avoid them

NASA Astrophysics Data System (ADS)

Safi, A.; Campanella, B.; Grifoni, E.; Legnaioli, S.; Lorenzetti, G.; Pagnotta, S.; Poggialini, F.; Ripoll-Seguer, L.; Hidalgo, M.; Palleschi, V.

2018-06-01

The introduction of multivariate calibration curve approach in Laser-Induced Breakdown Spectroscopy (LIBS) quantitative analysis has led to a general improvement of the LIBS analytical performances, since a multivariate approach allows to exploit the redundancy of elemental information that are typically present in a LIBS spectrum. Software packages implementing multivariate methods are available in the most diffused commercial and open source analytical programs; in most of the cases, the multivariate algorithms are robust against noise and operate in unsupervised mode. The reverse of the coin of the availability and ease of use of such packages is the (perceived) difficulty in assessing the reliability of the results obtained which often leads to the consideration of the multivariate algorithms as 'black boxes' whose inner mechanism is supposed to remain hidden to the user. In this paper, we will discuss the dangers of a 'black box' approach in LIBS multivariate analysis, and will discuss how to overcome them using the chemical-physical knowledge that is at the base of any LIBS quantitative analysis.

Application of Laser Induced Breakdown Spectroscopy in Early Detection of Red Palm Weevil: (Rhynchophorus ferrugineus) Infestation in Date Palm

NASA Astrophysics Data System (ADS)

A. Farooq, W.; G. Rasool, K.; Walid, Tawfik; S. Aldawood, A.

2015-11-01

The Kingdom of Saudi Arabia is one of the leading date producing countries. Unfortunately, this important fruit crop is under great threat from the red palm weevil (RPW) (Rhynchophorus ferrugineus), which is a highly invasive pest. Several techniques, including visual inspection, acoustic sensors, sniffer dogs, and pheromone traps have been tried to detect the early stages of a RPW infestation; however, each method has suffered certain logistical and implementation issues. We have applied laser induced breakdown spectroscopy (LIBS) for the early detection of RPW infestation. Through the analysis of the observed LIBS spectra of different infested and healthy samples, we have found presence of Ca, Mg, Na, C, K elements and OH, CN molecules. The spectra also reveal that with the population growth of the pest, the intensity of Mg and Ca atomic lines in LIBS spectra increases rapidly. Similar behavior is observed in the molecular lines of LIBS spectra. The obtained results indicate that the LIBS technique can be used for the early detection of RPW infestation without damaging the date palms.

A fundamental study of laser-induced breakdown spectroscopy using fiber optics for remote measurements of trace metals. Interim progress report

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

Goode, S.R.; Angel, S.M.

1997-01-01

'The long-term goal of this project is to develop a system to measure the elemental composition of unprepared samples using laser-induced breakdown spectroscopy, LIBS, with a fiber-optic probe. From images shown in this report it is evident that the temporal and spatial behavior of laser-induced plasmas IS a complex process. However, through the use of spectral imaging, optimal conditions can be determined for collecting the atomic emission signal in these plasmas. By tailoring signal collection to the regions of the plasma that contain the highest emission signal with the least amount of background interference both the detection limits and themore » precision of LIBS measurements could be improved. The optimal regions for both gated and possibly non-gated LIBS measurements have been shown to correspond to the inner regions and outer regions, respectively, in an axial plasma. By using this data fiber-optic LIBS probe designs can be optimized for collecting plasma emission at the optimal regions for improved detection limits and precision in a LIBS measurement.'« less

Long-Wave Infrared (LWIR) Molecular Laser-Induced Breakdown Spectroscopy (LIBS) Emissions of Thin Solid Explosive Powder Films Deposited on Aluminum Substrates.

PubMed

Yang, Clayton S-C; Jin, Feng; Trivedi, Sudhir B; Brown, Ei E; Hommerich, Uwe; Tripathi, Ashish; Samuels, Alan C

2017-04-01

Thin solid films made of high nitro (NO 2 )/nitrate (NO 3 ) content explosives were deposited on sand-blasted aluminum substrates and then studied using a mercury-cadmium-telluride (MCT) linear array detection system that is capable of rapidly capturing a broad spectrum of atomic and molecular laser-induced breakdown spectroscopy (LIBS) emissions in the long-wave infrared region (LWIR; ∼5.6-10 µm). Despite the similarities of their chemical compositions and structures, thin films of three commonly used explosives (RDX, HMX, and PETN) studied in this work can be rapidly identified in the ambient air by their molecular LIBS emission signatures in the LWIR region. A preliminary assessment of the detection limit for a thin film of RDX on aluminum appears to be much lower than 60 µg/cm 2 . This LWIR LIBS setup is capable of rapidly probing and charactering samples without the need for elaborate sample preparation and also offers the possibility of a simultaneous ultraviolet visible and LWIR LIBS measurement.

Evaluation of the efficacy of a portable LIBS system for detection of CWA on surfaces.

PubMed

L'Hermite, D; Vors, E; Vercouter, T; Moutiers, G

2016-05-01

Laser-induced breakdown spectroscopy (LIBS) is a laser-based optical technique particularly suited for in situ surface analysis. A portable LIBS instrument was tested to detect surface chemical contamination by chemical warfare agents (CWAs). Test of detection of surface contamination was carried out in a toxlab facility with four CWAs, sarin (GB), lewisite (L1), mustard gas (HD), and VX, which were deposited on different substrates, wood, concrete, military green paint, gloves, and ceramic. The CWAs were detected by means of the detection of atomic markers (As, P, F, Cl, and S). The LIBS instrument can give a direct response in terms of detection thanks to an integrated interface for non-expert users or so called end-users. We have evaluated the capability of automatic detection of the selected CWAs. The sensitivity of our portable LIBS instrument was confirmed for the detection of a CWA at surface concentrations above 15 μg/cm(2). The simultaneous detection of two markers may lead to a decrease of the number of false positive.

Applications of High Resolution Laser Induced Breakdown Spectroscopy for Environmental and Biological Samples

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

Martin, Madhavi Z; Labbe, Nicole; Wagner, Rebekah J.

2013-01-01

This chapter details the application of LIBS in a number of environmental areas of research such as carbon sequestration and climate change. LIBS has also been shown to be useful in other high resolution environmental applications for example, elemental mapping and detection of metals in plant materials. LIBS has also been used in phytoremediation applications. Other biological research involves a detailed understanding of wood chemistry response to precipitation variations and also to forest fires. A cross-section of Mountain pine (pinceae Pinus pungen Lamb.) was scanned using a translational stage to determine the differences in the chemical features both before andmore » after a fire event. Consequently, by monitoring the elemental composition pattern of a tree and by looking for abrupt changes, one can reconstruct the disturbance history of a tree and a forest. Lastly we have shown that multivariate analysis of the LIBS data is necessary to standardize the analysis and correlate to other standard laboratory techniques. LIBS along with multivariate statistical analysis makes it a very powerful technology that can be transferred from laboratory to field applications with ease.« less

High-Resolution Laser-Induced Breakdown Spectroscopy used in Homeland Security and Forensic Applications

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

Martin, Madhavi Z; Wullschleger, Stan D; Vass, Arpad Alexander

The technique of laser-induced breakdown spectroscopy (LIBS) to detect elements for a variety of homeland security applications such as nuclear materials identification and inventory,and forensic applications has been demonstrated. For nuclear materials applications, we detected and profiled metals in coatings that were used to encapsulate nuclear fuel. Multivariate analysis has been successfully employed in the quantification of elements present in treated wood and engineered wood composites. These examples demonstrate that LIBS-based techniques are inherently well suited for diverse environmental applications related to homeland security. Three key advantages are evident: (1) small samples (mg) are sufficient; (2) samples can be analyzedmore » by LIBS very rapidly, and (3) biological materials such as human and animal bones and wood can be analyzed with minimal sample preparation. For forensic applications they have used LIBS to determine differences in animal and human bones. They have also applied this technique in the determination of counterfeit and non-counterfeit currency. They recently applied LIBS in helping to solve a murder case.« less

Determination of the deuterium/hydrogen ratio in gas reaction products by laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

D'Ulivo, A.; Onor, M.; Pitzalis, E.; Spiniello, R.; Lampugnani, L.; Cristoforetti, G.; Legnaioli, S.; Palleschi, V.; Salvetti, A.; Tognoni, E.

2006-07-01

This paper reports the first application of laser-induced breakdown spectroscopy technique (LIBS) to the determination of deuterium/hydrogen numeric ratio ( β) in the headspace gases, essentially HD + H 2, that are generated by the hydrolysis of NaBD 4-NaBH 4 mixtures (molar fraction of NaBD 4, x = 50-100%) in acidic H 2O media (0 < pH < 1). The LIBS measurement of β can be easily achieved with a coefficient of variation better than 5% (over four replicates). The value of β allowed the calculation of the molar fraction of NaBD 4, xLIBS, with a coefficient of variation better than 2.5%. The comparison of x vs. xLIBS gives results that are in good agreement, within an average deviation of 3%, for x in the range of 50-100%. The best performances are obtained for β close to unit, which makes LIBS perfectly suited for the detection of H-D exchange taking place during aqueous hydrolysis of NaBD 4 or NaBH 4.

Remote quantitative analysis of minerals based on multispectral line-calibrated laser-induced breakdown spectroscopy (LIBS).

PubMed

Wan, Xiong; Wang, Peng

2014-01-01

Laser-induced breakdown spectroscopy (LIBS) is a feasible remote sensing technique used for mineral analysis in some unapproachable places where in situ probing is needed, such as analysis of radioactive elements in a nuclear leak or the detection of elemental compositions and contents of minerals on planetary and lunar surfaces. Here a compact custom 15 m focus optical component, combining a six times beam expander with a telescope, has been built, with which the laser beam of a 1064 nm Nd ; YAG laser is focused on remote minerals. The excited LIBS signals that reveal the elemental compositions of minerals are collected by another compact single lens-based signal acquisition system. In our remote LIBS investigations, the LIBS spectra of an unknown ore have been detected, from which the metal compositions are obtained. In addition, a multi-spectral line calibration (MSLC) method is proposed for the quantitative analysis of elements. The feasibility of the MSLC and its superiority over a single-wavelength determination have been confirmed by comparison with traditional chemical analysis of the copper content in the ore.

Detection of Anomalies in Citrus Leaves Using Laser-Induced Breakdown Spectroscopy (LIBS).

PubMed

Sankaran, Sindhuja; Ehsani, Reza; Morgan, Kelly T

2015-08-01

Nutrient assessment and management are important to maintain productivity in citrus orchards. In this study, laser-induced breakdown spectroscopy (LIBS) was applied for rapid and real-time detection of citrus anomalies. Laser-induced breakdown spectroscopy spectra were collected from citrus leaves with anomalies such as diseases (Huanglongbing, citrus canker) and nutrient deficiencies (iron, manganese, magnesium, zinc), and compared with those of healthy leaves. Baseline correction, wavelet multivariate denoising, and normalization techniques were applied to the LIBS spectra before analysis. After spectral pre-processing, features were extracted using principal component analysis and classified using two models, quadratic discriminant analysis and support vector machine (SVM). The SVM resulted in a high average classification accuracy of 97.5%, with high average canker classification accuracy (96.5%). LIBS peak analysis indicated that high intensities at 229.7, 247.9, 280.3, 393.5, 397.0, and 769.8 nm were observed of 11 peaks found in all the samples. Future studies using controlled experiments with variable nutrient applications are required for quantification of foliar nutrients by using LIBS-based sensing.

Linguistic intergroup bias in political communication.

PubMed

Anolli, Luigi; Zurloni, Valentino; Riva, Giuseppe

2006-07-01

The Linguistic Intergroup Bias (LIB) illustrates the disposition to communicate positive in-group and negative out-group behaviors more abstractly than negative in-group and positive out-group behaviors. The present research examined the function of language in reinforcing this bias in political communication. To illustrate the LIB, the Linguistic Category Model (LCM) was used, including a nouns category. Because social stereotypes are usually conveyed by nominal terms, the aim was to observe the relationship between stereotypes and language in political communication. Moreover, we were interested in analyzing the psychological processes that drive the LIB. Therefore, we verified whether the LIB is more related to language abstractness than to agent-patient causality. Several political debates and interviews, which took place before the latest Italian provincial elections, were analyzed. Results suggested that the language politicians use in communicating about political groups are conceptualized as stereotypes rather than as trait-based categories. Moreover, it seems that the LIB could not be explained only at a lexical level. Social implications of the present findings in interpersonal relations and causal attribution were discussed.

Study of Bacterial Samples Using Laser Induced Breakdown Spectroscopy

NASA Astrophysics Data System (ADS)

W, A. Farooq; M, Atif; W, Tawfik; M, S. Alsalhi; Z, A. Alahmed; M, Sarfraz; J, P. Singh

2014-12-01

Laser-induced breakdown spectroscopy (LIBS) technique has been applied to investigate two different types of bacteria, Escherichia coli (B1) and Micrococcus luteus (B2) deposited on glass slides using Spectrolaser 7000. LIBS spectra were analyzed using spectrolaser software. LIBS spectrum of glass substrate was compared with bacteria spectra. Ca, Mg, Na, K, P, S, Cl, Fe, Al, Mn, Cu, C, H and CN-band appeared in bacterial samples in air. Two carbon lines at 193.02 nm, 247.88 nm and one hydrogen line at 656.28 nm with intensity ratios of 1.9, 1.83 and 1.53 appeared in bacterial samples B1 and B2 respectively. Carbon and hydrogen are the important components of the bio-samples like bacteria and other cancer cells. Investigation on LIBS spectra of the samples in He and Ar atmospheres is also presented. Ni lines appeared only in B2 sample in Ar atmosphere. From the present experimental results we are able to show that LIBS technique has a potential in the identification and discrimination of different types of bacteria.

The Legacy of Patient H.M. for Neuroscience

PubMed Central

Squire, Larry R.

2009-01-01

H.M. is probably the best known single patient in the history of neuroscience. His severe memory impairment, which resulted from experimental neurosurgery to control seizures, was the subject of study for five decades until his death in December 2008. Work with H.M. established fundamental principles about how memory functions are organized in the brain. PMID:19146808

Investigation of Metal Oxide/Carbon Nano Material as Anode for High Capacity Lithium-ion Cells

NASA Technical Reports Server (NTRS)

Wu, James Jianjun; Hong, Haiping

2014-01-01

NASA is developing high specific energy and high specific capacity lithium-ion battery (LIB) technology for future NASA missions. Current state-of-art LIBs have issues in terms of safety and thermal stability, and are reaching limits in specific energy capability based on the electrochemical materials selected. For example, the graphite anode has a limited capability to store Li since the theoretical capacity of graphite is 372 mAh/g. To achieve higher specific capacity and energy density, and to improve safety for current LIBs, alternative advanced anode, cathode, and electrolyte materials are pursued under the NASA Advanced Space Power System Project. In this study, the nanostructed metal oxide, such as Fe2O3 on carbon nanotubes (CNT) composite as an LIB anode has been investigated.

A review on cellulose and lignin based binders and electrodes: Small steps towards a sustainable lithium ion battery.

PubMed

Nirmale, Trupti C; Kale, Bharat B; Varma, Anjani J

2017-10-01

Lithium ion batteries (LIB) are the most promising energy storage systems for portable electronics and future electric or hybrid-electric vehicles. However making them safer, cost effective and environment friendly is the key challenge. In this regard, replacing petro-derived materials by introducing renewable biomass derived cellulose derivatives and lignin based materials into the battery system is a promising approach for the development of green materials for LIB. These biomaterials introduce sustainability as well as improved safety in the final disposal of LIB batteries. In this review we introduce LIB materials technology in brief and recent developments in electrodes and binders based on cellulose and their derivatives and lignin for lithium ion batteries. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparative study on fast classification of brick samples by combination of principal component analysis and linear discriminant analysis using stand-off and table-top laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Vítková, Gabriela; Prokeš, Lubomír; Novotný, Karel; Pořízka, Pavel; Novotný, Jan; Všianský, Dalibor; Čelko, Ladislav; Kaiser, Jozef

2014-11-01

Focusing on historical aspect, during archeological excavation or restoration works of buildings or different structures built from bricks it is important to determine, preferably in-situ and in real-time, the locality of bricks origin. Fast classification of bricks on the base of Laser-Induced Breakdown Spectroscopy (LIBS) spectra is possible using multivariate statistical methods. Combination of principal component analysis (PCA) and linear discriminant analysis (LDA) was applied in this case. LIBS was used to classify altogether the 29 brick samples from 7 different localities. Realizing comparative study using two different LIBS setups - stand-off and table-top it is shown that stand-off LIBS has a big potential for archeological in-field measurements.

Enhancement of arachidonic acid signaling pathway by nicotinic acid receptor HM74A

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

Tang, Yuting; Zhou, Lubing; Gunnet, Joseph W.

2006-06-23

HM74A is a G protein-coupled receptor for nicotinic acid (niacin), which has been used clinically to treat dyslipidemia for decades. The molecular mechanisms whereby niacin exerts its pleiotropic effects on lipid metabolism remain largely unknown. In addition, the most common side effect in niacin therapy is skin flushing that is caused by prostaglandin release, suggesting that the phospholipase A{sub 2} (PLA{sub 2})/arachidonic acid (AA) pathway is involved. Various eicosanoids have been shown to activate peroxisome-proliferator activated receptors (PPAR) that play a diverse array of roles in lipid metabolism. To further elucidate the potential roles of HM74A in mediating the therapeuticmore » effects and/or side effects of niacin, we sought to explore the signaling events upon HM74A activation. Here we demonstrated that HM74A synergistically enhanced UTP- and bradykinin-mediated AA release in a pertussis toxin-sensitive manner in A431 cells. Activation of HM74A also led to Ca{sup 2+}-mobilization and enhanced bradykinin-promoted Ca{sup 2+}-mobilization through Gi protein. While HM74A increased ERK1/2 activation by the bradykinin receptor, it had no effects on UTP-promoted ERK1/2 activation.Furthermore, UTP- and bradykinin-mediated AA release was significantly decreased in the presence of both MAPK kinase inhibitor PD 098059 and PKC inhibitor GF 109203X. However, the synergistic effects of HM74A were not dramatically affected by co-treatment with both inhibitors, indicating the cross-talk occurred at the receptor level. Finally, stimulation of A431 cells transiently transfected with PPRE-luciferase with AA significantly induced luciferase activity, mimicking the effects of PPAR{gamma} agonist rosiglitazone, suggesting that alteration of AA signaling pathway can regulate gene expression via endogenous PPARs.« less

Goals for Human Milk Feeding in Mothers of Very Low Birth Weight Infants: How Do Goals Change and Are They Achieved During the NICU Hospitalization?

PubMed Central

Bigger, Harold; Patel, Aloka L.; Rossman, Beverly; Fogg, Louis F.; Meier, Paula

2015-01-01

Abstract Background: Little is known about human milk (HM) feeding goals for mothers of very low birth weight (VLBW) (<1,500 g birth weight) infants, especially for black mothers, for whom rates of VLBW birth are higher and lactation rates lower. This study examined the establishment, modification, and achievement of HM feeding goals during neonatal intensive care unit (NICU) hospitalization for mothers of VLBW infants and the influence of maternal race and income. Materials and Methods: A prospective cohort study measured maternal HM feeding goals (exclusive [EHM], partial, none) predelivery and during three time intervals: day of life (DOL) 1–14, 15–28, and 29–72. Goal achievement compared the goal for the time interval with the proportion of HM feedings received by the infant. Goal establishment, modification, and achievement were examined using chi-squared and contingency tables. Results: Three hundred fifty-two mother–infant dyads (53% black; 70% low-income; mean birth weight, 1,048 g) were studied. Predelivery, 55% of mothers planned to provide EHM; fewer black and low-income mothers chose EHM. During DOL 1–14, 63% of mothers chose EHM, and predelivery racial differences disappeared. Only 10% of mothers chose exclusive at-breast EHM feedings. EHM feeding goals decreased during NICU hospitalization, especially for black mothers. Whereas most mothers met their HM feeding goals initially, achievement rates declined during hospitalization. Mothers' EHM goal achievement was not influenced by race or income. Conclusions: Mothers changed their predelivery HM feeding goals after birth of a VLBW infant. Longitudinally, HM feeding goals and achievement reflected less HM use, highlighting the need to target lactation maintenance in this population. PMID:26110439

Biodegradation of used engine oil by novel strains of Ochrobactrum anthropi HM-1 and Citrobacter freundii HM-2 isolated from oil-contaminated soil.

PubMed

Ibrahim, Haytham M M

2016-12-01

Used engine oil (UEO) constitutes a serious environmental problem due to the difficulty of disposal off or reuse. Ten bacterial strains with biodegradation potential were isolated from UEO-contaminated soil sample using enrichment technique. Two strains which exhibited the highest degradation %, 51 ± 1.2 and 48 ± 1.5, respectively, were selected. Based on the morphological, biochemical characteristics and 16S rRNA sequence analysis, they were identified as Ochrobactrum anthropi HM-1 (accession no: KR360745) and Citrobacter freundii HM-2 (accession no: KR360746). The different conditions which may influence their biodegradation activity, including UEO concentration (1-6 %, v/v), inoculum size (0.5-4 %, v/v), initial pH (6-8), incubation temperature (25-45 °C), and rotation speed (0-200 rpm), were evaluated. The optimum conditions were found to be 2 % UEO, 2 % inoculum size, pH 7.5, incubation temperature 37 °C, and 150 rpm. Under the optimized conditions, strains HM-1, HM-2, and their mixture efficiently degraded UEO, they achieved 65 ± 2.2, 58 ± 2.1, and 80 ± 1.9 %, respectively, after 21 days of incubation. Biodegradation of UEO was confirmed by employing gas chromatography analysis. Gamma radiation (1.5 kGy) enhanced the degradation efficiency of irradiated bacterial mixture (95 ± 2.1 %) as compared to non-irradiated (79 ± 1.6 %). Therefore, strains HM-1 and HM-2 can be employed to develop a cost-effective method for bioremediation of used engine-oil-polluted soil.

Heavy metal accumulation and signal transduction in herbaceous and woody plants: Paving the way for enhancing phytoremediation efficiency.

PubMed

Luo, Zhi-Bin; He, Jiali; Polle, Andrea; Rennenberg, Heinz

2016-11-01

Heavy metal (HM)-accumulating herbaceous and woody plants are employed for phytoremediation. To develop improved strategies for enhancing phytoremediation efficiency, knowledge of the microstructural, physiological and molecular responses underlying HM-accumulation is required. Here we review the progress in understanding the structural, physiological and molecular mechanisms underlying HM uptake, transport, sequestration and detoxification, as well as the regulation of these processes by signal transduction in response to HM exposure. The significance of genetic engineering for enhancing phytoremediation efficiency is also discussed. In herbaceous plants, HMs are taken up by roots and transported into the root cells via transmembrane carriers for nutritional ions. The HMs absorbed by root cells can be further translocated to the xylem vessels and unloaded into the xylem sap, thereby reaching the aerial parts of plants. HMs can be sequestered in the cell walls, vacuoles and the Golgi apparatuses. Plant roots initially perceive HM stress and trigger the signal transduction, thereby mediating changes at the molecular, physiological, and microstructural level. Signaling molecules such as phytohormones, reactive oxygen species (ROS) and nitric oxide (NO), modulate plant responses to HMs via differentially expressed genes, activation of the antioxidative system and coordinated cross talk among different signaling molecules. A number of genes participated in HM uptake, transport, sequestration and detoxification have been functionally characterized and transformed to target plants for enhancing phytoremediation efficiency. Fast growing woody plants hold an advantage over herbaceous plants for phytoremediation in terms of accumulation of high HM-amounts in their large biomass. Presumably, woody plants accumulate HMs using similar mechanisms as herbaceous counterparts, but the processes of HM accumulation and signal transduction can be more complex in woody plants. Copyright © 2016 Elsevier Inc. All rights reserved.

[Carbon sequestration status of forest ecosystems in Ningxia Hui Autonomous Region].

PubMed

Gao, Yang; Jin, Jing-Wei; Cheng, Ji-Min; Su, Ji-Shuai; Zhu, Ren-Bin; Ma, Zheng-Rui; Liu, Wei

2014-03-01

Based on the data of Ningxia Hui Autonomous Region forest resources inventory, field investigation and laboratory analysis, this paper studied the carbon sequestration status of forest ecosystems in Ningxia region, estimated the carbon density and storage of forest ecosystems, and analyzed their spatial distribution characteristics. The results showed that the biomass of each forest vegetation component was in the order of arbor layer (46.64 Mg x hm(-2)) > litterfall layer (7.34 Mg x hm(-2)) > fine root layer (6.67 Mg x hm(-2)) > shrub-grass layer (0.73 Mg x hm(-2)). Spruce (115.43 Mg x hm(-2)) and Pinus tabuliformis (94.55 Mg x hm(-2)) had higher vegetation biomasses per unit area than other tree species. Over-mature forest had the highest arbor carbon density among the forests with different ages. However, the young forest had the highest arbor carbon storage (1.90 Tg C) due to its widest planted area. Overall, the average carbon density of forest ecosystems in Ningxia region was 265.74 Mg C x hm(-2), and the carbon storage was 43.54 Tg C. Carbon density and storage of vegetation were 27.24 Mg C x hm(-2) and 4.46 Tg C, respectively. Carbon storage in the soil was 8.76 times of that in the vegetation. In the southern part of Ningxia region, the forest carbon storage was higher than in the northern part, where the low C storage was mainly related to the small forest area and young forest age structure. With the improvement of forest age structure and the further implementation of forestry ecoengineering, the forest ecosystems in Ningxia region would achieve a huge carbon sequestration potential.

Roles of threonine 192 and asparagine 382 in agonist and antagonist interactions with M1 muscarinic receptors

PubMed Central

Huang, Xi-Ping; Nagy, Peter I; Williams, Frederick E; Peseckis, Steven M; Messer, William S

1999-01-01

Conserved amino acids, such as Thr in transmembrane domains (TM) V and Asn in TM VI of muscarinic receptors, may be important in agonist binding and/or receptor activation. In order to determine the functional roles of Thr192 and Asn382 in human M1 receptors in ligand binding and receptor activation processes, we created and characterized mutant receptors with Thr192 or Asn382 substituted by Ala.HM1 wild-type (WT) and mutant receptors [HM1(Thr192Ala) and HM1(Asn382Ala)] were stably expressed in A9 L cells. The Kd values for 3H-(R)-QNB and Ki values for other classical muscarinic antagonists were similar at HM1(WT) and HM1(Thr192Ala) mutant receptors, yet higher at HM1(Asn382Ala) mutant receptors. Carbachol exhibited lower potency and efficacy in stimulating PI hydrolysis via HM1(Thr192Ala) mutant receptors, and intermediate agonist activity at the HM1(Asn382Ala) mutant receptors.The Asn382 residue in TM VI but not the Thr192 residue in TM V of the human M1 receptor appears to participate directly in antagonist binding. Both Thr192 and Asn382 residues are involved differentially in agonist binding and/or receptor activation processes, yet the Asn382 residue is less important than Thr192 in agonist activation of M1 receptors.Molecular modelling studies indicate that substitution of Thr192 or Asn382 results in the loss of hydrogen-bond interactions and changes in the agonist binding mode associated with an increase in hydrophobic interactions between ligand and receptor. PMID:10188986

Markers of Oxidative Stress in Human Milk do not Differ by Maternal BMI But are Related to Infant Growth Trajectories.

PubMed

Young, Bridget E; Patinkin, Zachary W; Pyle, Laura; de la Houssaye, Becky; Davidson, Barbara S; Geraghty, Sheela; Morrow, Ardythe L; Krebs, Nancy

2017-06-01

Objective Obesity in adults is associated with inflammation and oxidative stress. Whether or not this phenotype is reflected in human milk (HM) composition, or may impact infant growth remains unknown. We investigated whether HM from overweight/obese (OW/Ob) mothers exhibited higher concentrations of inflammatory cytokines and markers of oxidative stress. We also correlated these bioactive components with infant growth patterns. Methods This was an observational cohort of 56 breastfeeding mothers and their infants [33 normal weight (NW) and 23 OW/Ob]. Infants were followed until 6 months of age and HM collected at 2-weeks and 4-months. Results Markers of oxidative stress, 8-hydroxy-deoxyguanosine (8OHdG) and 4-hydroxynonenol (HNE), decreased in HM over time (p < 0.001) and did not differ between NW and OW/Ob women. Concentrations of inflammatory cytokines, IL-6, IL-8, and TNF-α, were all inter-correlated (p < 0.001) but did not differ between NW and OW/Ob women. HM fat, protein, lactose, and total calories did not differ between NW and OW/Ob women. Infant growth patterns did not differ by group. In a model of infant weight-for-length-Z score trajectory, there was a significant interaction between both lactose and 8OHdG with maternal group: HM lactose and 8OHdG concentrations were both positively associated with increases in WLZ trajectory only among infants breastfed by OW/Ob mothers. Conclusions for Practice HM composition was relatively stable between NW and OW/Ob women. In exclusively breastfed infants, HM concentrations of lactose and 8OHdG, a marker of oxidative stress, may contribute to regulation of infant weight gain, especially among infants of OW/Ob women.

Assessment of viscoelasticity and hydration effect of herbal moisturizers using bioengineering techniques

PubMed Central

Kapoor, Shweta; Saraf, Swarnlata

2010-01-01

Background: A number of moisturizers are available containing natural hydrating, moisturizing, fi rming and occlusive property-imparting agent in the form of herbal extracts, juice and oils. The aim of this study is to assess the hydration and viscoelastic effect of commercially available herbal moisturizers, containing different herbs, on human skin, after a single and 3-week period of application using skin bio mechanical and electrical techniques. Materials and Methods: Twenty selected herbal moisturizers (HM) were coded as HM1-HM20. Forty volunteers, mean age of 40 ± 9 years, were participated in the short- and long-term study. Skin properties in terms of hydration and viscoelastic parameters were measured by multitester and cutometer, respectively. Measurements were done before and after 1, 2, and 3 h (single application) and for the 3-week period of daily application. Results: After single application, significant increase has been observed in both the skin electrical (P < 0.001) and mechanical properties (P < 0.01) as compared to the control, at which no products were applied. After the 3-week period, both effects are maintained and found to be significant at P < 0.001. Short-and long-term study revealed that out of 20 herbal moisturizers, HM8 and HM10 show pronounced increase in skin hydration (90-100%) and HM8, HM10, and HM11 shown marked increase in skin viscoelasticity (90-95%). Conclsuion: The possible reason of maximum effects obtained by these products is multifunctional effects of active ingredients of incorporated herbs. Combined used of both non invasive techniques is useful to substantiate the hydrating and viscoelasticity claim of herbal moisturizer. Short- and long-terms study revealed the best performing herbal moisturizer. PMID:21120032

The First Structure–Activity Relationship Studies for Designer Receptors Exclusively Activated by Designer Drugs

PubMed Central

2016-01-01

Over the past decade, two independent technologies have emerged and been widely adopted by the neuroscience community for remotely controlling neuronal activity: optogenetics which utilize engineered channelrhodopsin and other opsins, and chemogenetics which utilize engineered G protein-coupled receptors (Designer Receptors Exclusively Activated by Designer Drugs (DREADDs)) and other orthologous ligand–receptor pairs. Using directed molecular evolution, two types of DREADDs derived from human muscarinic acetylcholine receptors have been developed: hM3Dq which activates neuronal firing, and hM4Di which inhibits neuronal firing. Importantly, these DREADDs were not activated by the native ligand acetylcholine (ACh), but selectively activated by clozapine N-oxide (CNO), a pharmacologically inert ligand. CNO has been used extensively in rodent models to activate DREADDs, and although CNO is not subject to significant metabolic transformation in mice, a small fraction of CNO is apparently metabolized to clozapine in humans and guinea pigs, lessening the translational potential of DREADDs. To effectively translate the DREADD technology, the next generation of DREADD agonists are needed and a thorough understanding of structure–activity relationships (SARs) of DREADDs is required for developing such ligands. We therefore conducted the first SAR studies of hM3Dq. We explored multiple regions of the scaffold represented by CNO, identified interesting SAR trends, and discovered several compounds that are very potent hM3Dq agonists but do not activate the native human M3 receptor (hM3). We also discovered that the approved drug perlapine is a novel hM3Dq agonist with >10 000-fold selectivity for hM3Dq over hM3. PMID:25587888

Genotype and phenotype correlation in von Hippel-Lindau disease based on alteration of the HIF-α binding site in VHL protein.

PubMed

Liu, Sheng-Jie; Wang, Jiang-Yi; Peng, Shuang-He; Li, Teng; Ning, Xiang-Hui; Hong, Bao-An; Liu, Jia-Yuan; Wu, Peng-Jie; Zhou, Bo-Wen; Zhou, Jing-Cheng; Qi, Nie-Nie; Peng, Xiang; Zhang, Jiu-Feng; Ma, Kai-Fang; Cai, Lin; Gong, Kan

2018-03-29

PurposeVon Hippel-Lindau (VHL) disease is a rare hereditary cancer syndrome that reduces life expectancy. We aimed to construct a more valuable genotype-phenotype correlation based on alterations in VHL protein (pVHL).MethodsVHL patients (n = 339) were recruited and grouped based on mutation types: HIF-α binding site missense (HM) mutations, non-HIF-α binding site missense (nHM) mutations, and truncating (TR) mutations. Age-related risks of VHL-associated tumors and patient survival were compared.ResultsMissense mutations conferred an increased risk of pheochromocytoma (HR = 1.854, p = 0.047) compared with truncating mutations. The risk of pheochromocytoma was lower in the HM group than in the nHM group (HR = 0.298, p = 0.003) but was similar between HM and TR groups (HR = 0.901, p = 0.810). Patients in the nHM group had a higher risk of pheochromocytoma (HR = 3.447, p < 0.001) and lower risks of central nervous system hemangioblastoma (CHB) (HR = 0.700, p = 0.045), renal cell carcinoma (HR = 0.610, p = 0.024), and pancreatic tumor (HR = 0.382, p < 0.001) than those in the combined HM and TR (HMTR) group. Moreover, nHM mutations were independently associated with better overall survival (HR = 0.345, p = 0.005) and CHB-specific survival (HR = 0.129, p = 0.005) than HMTR mutations.ConclusionThe modified genotype-phenotype correlation links VHL gene mutation, substrate binding site, and phenotypic diversity (penetrance and survival), and provides more accurate information for genetic counseling and pathogenesis studies.Genetics in Medicine advance online publication, 29 March 2018; doi:10.1038/gim.2017.261.

FELASA recommendations for the health monitoring of mouse, rat, hamster, guinea pig and rabbit colonies in breeding and experimental units.

PubMed

Mähler Convenor, M; Berard, M; Feinstein, R; Gallagher, A; Illgen-Wilcke, B; Pritchett-Corning, K; Raspa, M

2014-07-01

The microbiological quality of experimental animals can critically influence animal welfare and the validity and reproducibility of research data. It is therefore important for breeding and experimental facilities to establish a laboratory animal health monitoring (HM) programme as an integrated part of any quality assurance system. FELASA has published recommendations for the HM of rodent and rabbit colonies in breeding and experimental units (Nicklas et al. Laboratory Animals, 2002), with the intention of harmonizing HM programmes. As stated in the preamble, these recommendations need to be adapted periodically to meet current developments in laboratory animal medicine. Accordingly, previous recommendations have been revised and shall be replaced by the present recommendations. These recommendations are aimed at all breeders and users of laboratory mice, rats, Syrian hamsters, guinea pigs and rabbits as well as diagnostic laboratories. They describe essential aspects of HM, such as the choice of agents, selection of animals and tissues for testing, frequency of sampling, commonly used test methods, interpretation of results and HM reporting. Compared with previous recommendations, more emphasis is put on the role of a person with sufficient understanding of the principles of HM, opportunistic agents, the use of sentinel animals (particularly under conditions of cage-level containment) and the interpretation and reporting of HM results. Relevant agents, testing frequencies and literature references are updated. Supplementary information on specific agents and the number of animals to be monitored and an example of a HM programme description is provided in the appendices. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

[Effects of small hydropower substitute fuel project on forest ecosystem services].

PubMed

Yu, Hai Yan; Zha, Tong Gang; Nie, Li Shui; Lyu, Zhi Yuan

2016-10-01

Based on the Forest Ecosystem Services Assessment Standards (LY/T 1721－2008) issued by the State Forestry Administration, this paper evaluated four key functions of forest ecosystems, i.e., water conservation, soil conservation, carbon fixation and oxygen release, and nutrient accumulation. Focusing on the project area of Majiang County in Guizhou Province, this study provided some quantitative evidence that the implementation of the small hydropower substituting fuel project had positive effects on the values and material quantities of ecosystem service functions. The results showed that the small hydropower substituting fuel project had a significant effect on the increase of forest ecosystem services. Water conservation quantity of Pinus massoniana and Cupressus funebris plantations inside project area was 20662.04 m 3 ·hm -2 ·a -1 , 20.5% higher than outside project area, with soil conservation quantity of 119.1 t·hm -2 ·a -1 , 29.7% higher than outside project area, carbon fixation and oxygen release of 220.49 t·hm -2 ·a -1 , 40.2% higher than outside project area, and forest tree nutrition accumulation of 3.49 t·hm -2 ·a -1 , 48.5% higher than outside project area. Small hydropower substituting fuel project for increasing the quota of forest ecosystem service function value was in the order of carbon fixation and oxygen release function (71400 yuan·hm -2 ·a -1 ) > water conservation function (60100 yuan·hm -2 ·a -1 ) > tree nutrition accumulation function (13800 yuan·hm -2 ·a -1 ) > soil conservation function (8100 yuan·hm -2 ·a -1 ). Small hydropower substituting fuel project played an important role for improving the forest ecological service function value and realizing the sustainable development of forest.

Analysis of Operational Parameters Affecting the Sulfur Content in Hot Metal of the COREX Process

NASA Astrophysics Data System (ADS)

Wu, Shengli; Wang, Laixin; Kou, Mingyin; Wang, Yujue; Zhang, Jiacong

2017-02-01

The COREX process, which has obvious advantages in environment protection, still has some disadvantages. It has a higher sulfur content in hot metal (HM) than the blast furnace has. In the present work, the distribution and transfer of sulfur in the COREX have been analyzed and several operational parameters related to the sulfur content in HM ([pct S]) have been obtained. Based on this, the effects of the coal rate, slag ratio, temperature of HM, melting rate, binary basicity ( R 2), the ratio of MgO/Al2O3, utilization of reducing gas, top gas consumption per ton burden solid, metallization rate, oxidation degree of reducing gas, and coal and DRI distribution index on the sulfur content in HM are investigated. What's more, a linear model has been developed and subsequently used for predicting and controlling the S content in HM of the COREX process.

Maternal and infant characteristics associated with human milk feeding in very low birth weight infants.

PubMed

Sisk, Paula M; Lovelady, Cheryl A; Dillard, Robert G; Gruber, Kenneth J; O'Shea, T Michael

2009-11-01

This study identified maternal and infant characteristics predicting human milk (HM) feeding in very low birth weight (VLBW) infants whose mothers (n = 184) participated in a study of lactation counseling and initiated milk expression. Data were collected prospectively, by maternal interview and medical record review. During hospitalization, 159 (86%) infants received at least 50% HM proportion of feedings in the first 2 weeks of life, and 114 (62%) received some HM until the day of hospital discharge. Analysis showed plan to breastfeed was the strongest predictor of initiation and duration of HM feeding. Greater than 12 years of education, respiratory distress syndrome, Apgar score >6, and female gender were significant predictors, and no perinatal hypertensive disorder, white race, and mechanical ventilation were marginal predictors of HM feeding. Women with a high-risk pregnancy should be provided education about the benefits of breastfeeding for infants who are likely to be born prematurely.

The Influence of Hydroxylation on Maintaining CpG Methylation Patterns: A Hidden Markov Model Approach.

PubMed

Giehr, Pascal; Kyriakopoulos, Charalampos; Ficz, Gabriella; Wolf, Verena; Walter, Jörn

2016-05-01

DNA methylation and demethylation are opposing processes that when in balance create stable patterns of epigenetic memory. The control of DNA methylation pattern formation by replication dependent and independent demethylation processes has been suggested to be influenced by Tet mediated oxidation of 5mC. Several alternative mechanisms have been proposed suggesting that 5hmC influences either replication dependent maintenance of DNA methylation or replication independent processes of active demethylation. Using high resolution hairpin oxidative bisulfite sequencing data, we precisely determine the amount of 5mC and 5hmC and model the contribution of 5hmC to processes of demethylation in mouse ESCs. We develop an extended hidden Markov model capable of accurately describing the regional contribution of 5hmC to demethylation dynamics. Our analysis shows that 5hmC has a strong impact on replication dependent demethylation, mainly by impairing methylation maintenance.

Circumstellar dust in symbiotic novae

NASA Astrophysics Data System (ADS)

Jurkic, Tomislav; Kotnik-Karuza, Dubravka

2015-08-01

Physical properties of the circumstellar dust and associated physical mechanisms play an important role in understanding evolution of symbiotic binaries. We present a model of inner dust regions around the cool Mira component of the two symbiotic novae, RR Tel and HM Sge, based on the long-term near-IR photometry, infrared ISO spectra and mid-IR interferometry. Pulsation properties and long-term variabilities were found from the near-IR light curves. The dust properties were determined using the DUSTY code which solves the radiative transfer. No changes in pulsational parameters were found, but a long-term variations with periods of 20-25 years have been detected which cannot be attributed to orbital motion.Circumstellar silicate dust shell with inner dust shell temperatures between 900 K and 1300 K and of moderate optical depth can explain all the observations. RR Tel showed the presence of an optically thin CS dust envelope and an optically thick dust region outside the line of sight, which was further supported by the detailed modelling using the 2D LELUYA code. Obscuration events in RR Tel were explained by an increase in optical depth caused by the newly condensed dust leading to the formation of a compact dust shell. HM Sge showed permanent obscuration and a presence of a compact dust shell with a variable optical depth. Scattering of the near-IR colours can be understood by a change in sublimation temperature caused by the Mira variability. Presence of large dust grains (up to 4 µm) suggests an increased grain growth in conditions of increased mass loss. The mass loss rates of up to 17·10-6 MSun/yr were significantly higher than in intermediate-period single Miras and in agreement with longer-period O-rich AGB stars.Despite the nova outburst, HM Sge remained enshrouded in dust with no significant dust destruction. The existence of unperturbed dust shell suggests a small influence of the hot component and strong dust shielding from the UV flux. By the use of the CLOUDY code, we have showed that a high-density gas region can effectively stop most of the UV flux from the white dwarf and provide the observed dust shielding.

Applications of Laser-Induced Breakdown Spectroscopy (LIBS) in Molten Metal Processing

NASA Astrophysics Data System (ADS)

Hudson, Shaymus W.; Craparo, Joseph; De Saro, Robert; Apelian, Diran

2017-10-01

In order for metals to meet the demand for critical applications in the automotive, aerospace, and defense industries, tight control over the composition and cleanliness of the metal must be achieved. The use of laser-induced breakdown spectroscopy (LIBS) for applications in metal processing has generated significant interest for its ability to perform quick analyses in situ. The fundamentals of LIBS, current techniques for deployment on molten metal, demonstrated capabilities, and possible avenues for development are reviewed and discussed.

Laboratory Evaluation of Laser-Induced Breakdown Spectroscopy (LIBS) as a New in situ Chemical Sensing Technique for the Deep Ocean

DTIC Science & Technology

2007-09-01

1.1.2 Advantages and Disadvantages of the LIBS Technique ..... .. 21 1.1.3 LIBS in Liquids ................................ 23 1.2 Scientific ...1.2 Scientific Application: Hydrothermal Vent Chemistry Study of in situ hydrothermal vent chemistry could benefit greatly from the develop- ment of a...4935, 1994. [50] K. L. Von Danim . Chemistry of hydrothermal vent fluids froin 90 - 100 N, East Pacific Rise: ’Time zero,’ The inmnediate posteruptive

Challenging the concept of electrochemical discharge using salt solutions for lithium-ion batteries recycling.

PubMed

Ojanen, Severi; Lundström, Mari; Santasalo-Aarnio, Annukka; Serna-Guerrero, Rodrigo

2018-06-01

The use of lithium-ion batteries (LIB) has grown significantly in recent years, making them a promising source of secondary raw materials due to their rich composition of valuable materials such as Co, Ni and Al. However, the high voltage and reactive components of LIBs pose safety hazards during crushing stages in recycling processes, and during storage and transportation. Electrochemical discharge by immersion of spent batteries in salt solutions has been generally accepted as a robust and straightforward discharging step to address these potential hazards. Nonetheless, there is no clear evidence in the literature to support the use of electrochemical discharge in real systems, neither are there clear indications of the real-world limitations of this practice. To that aim, this work presents a series of experiments systematically conducted to study the behavior of LIBs during electrochemical discharge in salt solutions. In the first part of this study, a LIB sample was discharged ex-situ using Pt wires connected to the battery poles and submerged into the electrolyte solution on the opposite end. The evolution of voltage in the battery was measured for solutions of NaCl, NaSO 4 , FeSO 4 , and ZnSO 4 . The results indicate that, among the electrolytes used in the present study, NaCl solution is the most effective for LIBs discharge. The discharge of LIB using sulfate salts is however only possible with the aid of stirring, as deposition of solid precipitated on the electrodes hinder the electrochemical discharge. Furthermore, it was found that the addition of particulates of Fe or Zn as sacrificial metal further enhances the discharging rate, likely due to an increased contact area with the electrolyte solution. While these findings support the idea of using electrochemical discharge as a pre-treatment of LIBs, severe corrosion of the battery poles was observed upon direct immersion of batteries into electrolyte solutions. Prevention of such corrosion requires further research efforts, perhaps focused on a new design-for-recycling approach of LIBs. Copyright © 2018 Elsevier Ltd. All rights reserved.

U.S. Pacific Command > About USPACOM > History

Science.gov Websites

H.M. Smith, which is also the headquarters of Commander, Marine Forces Pacific. CINCPAC also served Unit Awards. History of Camp H.M. Smith Camp H.M. Smith, home of the headquarters of Commander, U.S highly regarded Marine leader during World War II, General Holland McTyeire Smith. The Marines took up

Amnesic H.M. Exhibits Parallel Deficits and Sparing in Language and Memory: Systems versus Binding Theory Accounts

ERIC Educational Resources Information Center

MacKay, Donald G.; James, Lori E.; Taylor, Jennifer K.; Marian, Diane E.

2007-01-01

This study examines sentence-level language abilities of amnesic H.M. to test competing theoretical conceptions of relations between language and memory. We present 11 new sources of experimental evidence indicating deficits in H.M's comprehension and production of non-cliche sentences. Contrary to recent claims that H.M.'s comprehension is…

Synthesis and Multiple Incorporations of 2′‐O‐Methyl‐5‐hydroxymethylcytidine, 5‐Hydroxymethylcytidine and 5‐Formylcytidine Monomers into RNA Oligonucleotides

PubMed Central

Tanpure, Arun A.

2017-01-01

Abstract The synthesis of 2′‐O‐methyl‐5‐hydroxymethylcytidine (hm5Cm), 5‐hydroxymethylcytidine (hm5C) and 5‐formylcytidine (f5C) phosphoramidite monomers has been developed. Optimisation of mild post‐synthetic deprotection conditions enabled the synthesis of RNA containing all four naturally occurring cytosine modifications (hm5Cm, hm5C, f5C plus 5‐methylcytosine). Given the considerable interest in RNA modifications and epitranscriptomics, the availability of synthetic monomers and RNAs containing these modifications will be valuable for elucidating their biological function(s). PMID:28901692

Atmospheric Deposition-Carried Zn and Cd from a Zinc Smelter and Their Effects on Soil Microflora as Revealed by 16S rDNA

PubMed Central

Shen, Feng; Li, Yanxia; Zhang, Min; Awasthi, Mukesh Kumar; Ali, Amjad; Li, Ronghua; Wang, Quan; Zhang, Zengqiang

2016-01-01

In this study, we investigated the influence of heavy metals (HM) on total soil bacterial population and its diversity pattern from 10 km distance of a Zinc smelter in Feng County, Qinling Mountain, China. We characterized and identified the bacterial community in a HM polluted soil using 16S rDNA technology. Out results indicated that the maximum soil HM concentration and the minimum bacterial population were observed in S2 soil, whereas bacterial diversity raised with the sampling distance increased. The bacterial communities were dominated by the phyla Proteobacteria, Acidobacteria and Actinobacteria in cornfield soils, except Fimicutes phylum which dominated in hilly area soil. The soil CEC, humic acid (HA)/fulvic acid (FA) and microbial OTUs increased with the sampling distance increased. Shewanella, Halomonas and Escherichia genera were highly tolerant to HM stress in both cultivated and non-cultivated soil. Finally, we found a consistent correlation of bacterial diversity with total HM and SOM along the sampling distance surrounding the zinc smelter, which could provide a new insight into the bacterial community-assisted and phytoremediation of HM contaminated soils. PMID:27958371

Human milk feeding protects very low-birth-weight infants from retinopathy of prematurity: a pre-post cohort analysis.

PubMed

Ginovart, Gemma; Gich, Ignasi; Verd, Sergio

2016-12-01

To examine the effect of early human milk (HM) feeding on the incidence of retinopathy of prematurity (ROP) among very low-birth-weight (VLBW) infants. Observational cohort research in a Level III neonatal intensive care unit. A total of 186 infants were enrolled in this pre-post cohort study (114 infants were included in the HM-fed group and 72 in the formula-fed group). ROP, type of feeding (early exclusive HM versus any formula), and potential confounding variables were measured. Differences between groups were explored. The clinical characteristics of the neonates did not differ between the two groups. By bivariate analysis, HM feeding was associated with 75% lower odds of Stage 2 or 3 ROP (OR = 0.25, 95% CI: 0.091 to 0.705; p = 0.009) At multivariate logistic regression, type of milk feeding retained significance, exclusive HM being protective with p = 0.002. This study found an association between early exposure to formula in VLBW infants and ROP. An initial HM diet, devoid of cow milk-containing products before achieving full enteral feeding, may help prevent ROP.

Atmospheric Deposition-Carried Zn and Cd from a Zinc Smelter and Their Effects on Soil Microflora as Revealed by 16S rDNA

NASA Astrophysics Data System (ADS)

Shen, Feng; Li, Yanxia; Zhang, Min; Awasthi, Mukesh Kumar; Ali, Amjad; Li, Ronghua; Wang, Quan; Zhang, Zengqiang

2016-12-01

In this study, we investigated the influence of heavy metals (HM) on total soil bacterial population and its diversity pattern from 10 km distance of a Zinc smelter in Feng County, Qinling Mountain, China. We characterized and identified the bacterial community in a HM polluted soil using 16S rDNA technology. Out results indicated that the maximum soil HM concentration and the minimum bacterial population were observed in S2 soil, whereas bacterial diversity raised with the sampling distance increased. The bacterial communities were dominated by the phyla Proteobacteria, Acidobacteria and Actinobacteria in cornfield soils, except Fimicutes phylum which dominated in hilly area soil. The soil CEC, humic acid (HA)/fulvic acid (FA) and microbial OTUs increased with the sampling distance increased. Shewanella, Halomonas and Escherichia genera were highly tolerant to HM stress in both cultivated and non-cultivated soil. Finally, we found a consistent correlation of bacterial diversity with total HM and SOM along the sampling distance surrounding the zinc smelter, which could provide a new insight into the bacterial community-assisted and phytoremediation of HM contaminated soils.

An interval chance-constrained fuzzy modeling approach for supporting land-use planning and eco-environment planning at a watershed level.

PubMed

Ou, Guoliang; Tan, Shukui; Zhou, Min; Lu, Shasha; Tao, Yinghui; Zhang, Zuo; Zhang, Lu; Yan, Danping; Guan, Xingliang; Wu, Gang

2017-12-15

An interval chance-constrained fuzzy land-use allocation (ICCF-LUA) model is proposed in this study to support solving land resource management problem associated with various environmental and ecological constraints at a watershed level. The ICCF-LUA model is based on the ICCF (interval chance-constrained fuzzy) model which is coupled with interval mathematical model, chance-constrained programming model and fuzzy linear programming model and can be used to deal with uncertainties expressed as intervals, probabilities and fuzzy sets. Therefore, the ICCF-LUA model can reflect the tradeoff between decision makers and land stakeholders, the tradeoff between the economical benefits and eco-environmental demands. The ICCF-LUA model has been applied to the land-use allocation of Wujiang watershed, Guizhou Province, China. The results indicate that under highly land suitable conditions, optimized area of cultivated land, forest land, grass land, construction land, water land, unused land and landfill in Wujiang watershed will be [5015, 5648] hm 2 , [7841, 7965] hm 2 , [1980, 2056] hm 2 , [914, 1423] hm 2 , [70, 90] hm 2 , [50, 70] hm 2 and [3.2, 4.3] hm 2 , the corresponding system economic benefit will be between 6831 and 7219 billion yuan. Consequently, the ICCF-LUA model can effectively support optimized land-use allocation problem in various complicated conditions which include uncertainties, risks, economic objective and eco-environmental constraints. Copyright © 2017 Elsevier Ltd. All rights reserved.

Genotypic-dependent effects of N fertilizer, glutathione, silicon, zinc, and selenium on proteomic profiles, amino acid contents, and quality of rice genotypes with contrasting grain Cd accumulation.

PubMed

Cao, Fangbin; Fu, Manman; Wang, Runfeng; Cheng, Wangda; Zhang, Guoping; Wu, Feibo

2017-07-01

Soil heavy metal (HM) contamination has posed a serious problem for safe food production. For restricting the translocation of HM into grain, many proteins were regulated to involve in the process. To identify these proteins, 2D-based proteomic analysis was carried out using different rice genotypes with distinct Cd accumulation in grains and as affected by an alleviating regulator (AR) in field experiments. AR application improved grain quality, with increased contents in Glu, Cys, His, Pro, and protein. Twenty-six low-grain HM accumulation-associated protein species were identified and categorized as physiological functions via two-dimensional gel electrophoresis (2DE) and mass spectrometry. Among these proteins, 8, 9, and 9 proteins exhibited higher accumulation, lower accumulation, and unchanged accumulation, respectively, in Xiushui817 (low accumulator) vs R8097 (high accumulator) under control conditions but showed differential accumulation patterns after AR application. These proteins included sucrose synthase 3, alanine aminotransferase, glutelin, cupin family protein, and zinc finger CCCH domain-containing protein 32. The differential expression of these protein species might contribute to decreased HM accumulation in grain via decreasing the protein accumulation which had high affinity to HM or regulating energy metabolism and signal transduction. Our findings provide valuable insights into the mechanisms of low-grain HM accumulation in rice and possible utilization of candidate protein species in developing low-grain HM accumulation genotypes.

A Review: Enhanced Anodes of Li/Na-Ion Batteries Based on Yolk-Shell Structured Nanomaterials

NASA Astrophysics Data System (ADS)

Wu, Cuo; Tong, Xin; Ai, Yuanfei; Liu, De-Sheng; Yu, Peng; Wu, Jiang; Wang, Zhiming M.

2018-09-01

Lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk-shell (YS) structured materials have emerged as a promising strategy toward improving lithium and sodium storage. YS structures possess unique interior void space, large surface area and short diffusion distance, which can solve the problems of volume expansion and aggregation of anode materials, thus enhancing the performance of LIBs and SIBs. In this review, we present a brief overview of recent advances in the novel YS structures of spheres, polyhedrons and rods with controllable morphology and compositions. Enhanced electrochemical performance of LIBs and SIBs based on these novel YS structured anode materials was discussed in detail. [Figure not available: see fulltext.

Effect of notch depth of modified current collector on internal-short-circuit mitigation for lithium-ion battery

NASA Astrophysics Data System (ADS)

Wang, Meng; Noelle, Daniel J.; Shi, Yang; Le, Anh V.; Qiao, Yu

2018-01-01

Formation of internal short circuit (ISC) may result in catastrophic thermal runaway of lithium-ion battery (LIB). Among LIB cell components, direct contact between cathode and anode current collectors is most critical to the ISC behavior, yet is still relatively uninvestigated. In the current study, we analyze the effect of heterogeneity of current collector on the temperature increase of LIB cells subjected to mechanical abuse. The cathode current collector is modified by surface notches, so that it becomes effectively brittle and the ISC site can be isolated. Results from impact tests on LIB cells with modified current collectors suggest that their temperature increase can be negligible. The critical parameters include the failure strain and the failure work of modified current collector, both of which are related to the notch depth.

Detection and identification of amino acids in Ficoll solutions with femtosecond laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Markushin, Y.; Sivakumar, P.; Melikechi, N.; Boukari, H.

2018-02-01

We report femtosecond Laser-induced Breakdown Spectroscopy (fs-LIBS) measurements on several amino acids (Serine, Glutamine, and Cysteine) and Albumin protein solutions mixed with Ficoll polysaccharide at different proportions. The goal is to assess the effects of a host matrix on the identification and spectral characterization of amino acids by fs-LIBS. fs-LIBS utilizes an intense short laser pulse to obliterate a sample into basic constituents and to record the emission spectrum of atoms, ions, and molecules in the cooling down of the plasma plume. Several spectral peaks associated primarily with elemental composition of a sample were observed in the fs-LIBS spectra in a range from 200 to 950 nm. In addition, some molecular information associated with diatomic vibrational modes in certain molecules such as C-C and C-N were also obtained. The presence of Ficoll affects the relative intensity and broadening of the CN band, which could be considered as signatures of the amino acids. The fs-LIBS data and their analysis compare favorably with those derived from Fourier Transform Infrared Spectroscopy (FTIR). Interpretation of the spectral information enclosed in the emission of the diatomic molecules during laser ablation may lead to a better understanding of plume chemistry with a direct consequence on chemical analysis of complex samples such as amino acids. Altogether, the results demonstrate the potential of fs-LIBS technique as a detection method of biomolecules and for probing interactions of these biomolecules with a host matrix.

LibKiSAO: a Java library for Querying KiSAO.

PubMed

Zhukova, Anna; Adams, Richard; Laibe, Camille; Le Novère, Nicolas

2012-09-24

The Kinetic Simulation Algorithm Ontology (KiSAO) supplies information about existing algorithms available for the simulation of Systems Biology models, their characteristics, parameters and inter-relationships. KiSAO enables the unambiguous identification of algorithms from simulation descriptions. Information about analogous methods having similar characteristics and about algorithm parameters incorporated into KiSAO is desirable for simulation tools. To retrieve this information programmatically an application programming interface (API) for KiSAO is needed. We developed libKiSAO, a Java library to enable querying of the KiSA Ontology. It implements methods to retrieve information about simulation algorithms stored in KiSAO, their characteristics and parameters, and methods to query the algorithm hierarchy and search for similar algorithms providing comparable results for the same simulation set-up. Using libKiSAO, simulation tools can make logical inferences based on this knowledge and choose the most appropriate algorithm to perform a simulation. LibKiSAO also enables simulation tools to handle a wider range of simulation descriptions by determining which of the available methods are similar and can be used instead of the one indicated in the simulation description if that one is not implemented. LibKiSAO enables Java applications to easily access information about simulation algorithms, their characteristics and parameters stored in the OWL-encoded Kinetic Simulation Algorithm Ontology. LibKiSAO can be used by simulation description editors and simulation tools to improve reproducibility of computational simulation tasks and facilitate model re-use.

Wheel-running reinforcement in free-feeding and food-deprived rats.

PubMed

Belke, Terry W; Pierce, W David

2016-03-01

Rats experiencing sessions of 30min free access to wheel running were assigned to ad-lib and food-deprived groups, and given additional sessions of free wheel activity. Subsequently, both ad-lib and deprived rats lever pressed for 60s of wheel running on fixed ratio (FR) 1, variable ratio (VR) 3, VR 5, and VR 10 schedules, and on a response-initiated variable interval (VI) 30s schedule. Finally, the ad-lib rats were switched to food deprivation and the food-deprived rats were switched to free food, as rats continued responding on the response-initiated VI 30-s schedule. Wheel running functioned as reinforcement for both ad-lib and food-deprived rats. Food-deprived rats, however, ran faster and had higher overall lever-pressing rates than free-feeding rats. On the VR schedules, wheel-running rates positively correlated with local and overall lever pressing rates for deprived, but not ad-lib rats. On the response-initiated VI 30s schedule, wheel-running rates and lever-pressing rates changed for ad-lib rats switched to food deprivation, but not for food-deprived rats switched to free-feeding. The overall pattern of results suggested different sources of control for wheel running: intrinsic motivation, contingencies of automatic reinforcement, and food-restricted wheel running. An implication is that generalizations about operant responding for wheel running in food-deprived rats may not extend to wheel running and operant responding of free-feeding animals. Copyright © 2015 Elsevier B.V. All rights reserved.

Standoff detection of chemical and biological threats using laser-induced breakdown spectroscopy.

PubMed

Gottfried, Jennifer L; De Lucia, Frank C; Munson, Chase A; Miziolek, Andrzej W

2008-04-01

Laser-induced breakdown spectroscopy (LIBS) is a promising technique for real-time chemical and biological warfare agent detection in the field. We have demonstrated the detection and discrimination of the biological warfare agent surrogates Bacillus subtilis (BG) (2% false negatives, 0% false positives) and ovalbumin (0% false negatives, 1% false positives) at 20 meters using standoff laser-induced breakdown spectroscopy (ST-LIBS) and linear correlation. Unknown interferent samples (not included in the model), samples on different substrates, and mixtures of BG and Arizona road dust have been classified with reasonable success using partial least squares discriminant analysis (PLS-DA). A few of the samples tested such as the soot (not included in the model) and the 25% BG:75% dust mixture resulted in a significant number of false positives or false negatives, respectively. Our preliminary results indicate that while LIBS is able to discriminate biomaterials with similar elemental compositions at standoff distances based on differences in key intensity ratios, further work is needed to reduce the number of false positives/negatives by refining the PLS-DA model to include a sufficient range of material classes and carefully selecting a detection threshold. In addition, we have demonstrated that LIBS can distinguish five different organophosphate nerve agent simulants at 20 meters, despite their similar stoichiometric formulas. Finally, a combined PLS-DA model for chemical, biological, and explosives detection using a single ST-LIBS sensor has been developed in order to demonstrate the potential of standoff LIBS for universal hazardous materials detection.

Assessment and forensic application of laser-induced breakdown spectroscopy (LIBS) for the discrimination of Australian window glass.

PubMed

El-Deftar, Moteaa M; Speers, Naomi; Eggins, Stephen; Foster, Simon; Robertson, James; Lennard, Chris

2014-08-01

A commercially available laser-induced breakdown spectroscopy (LIBS) instrument was evaluated for the determination of elemental composition of twenty Australian window glass samples, consisting of 14 laminated samples and 6 non-laminated samples (or not otherwise specified) collected from broken windows at crime scenes. In this study, the LIBS figures of merit were assessed in terms of accuracy, limits of detection and precision using three standard reference materials (NIST 610, 612, and 1831). The discrimination potential of LIBS was compared to that obtained using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), X-ray microfluorescence spectroscopy (μXRF) and scanning electron microscopy energy dispersive X-ray spectrometry (SEM-EDX) for the analysis of architectural window glass samples collected from crime scenes in the Canberra region, Australia. Pairwise comparisons were performed using a three-sigma rule, two-way ANOVA and Tukey's HSD test at 95% confidence limit in order to investigate the discrimination power for window glass analysis. The results show that the elemental analysis of glass by LIBS provides a discrimination power greater than 97% (>98% when combined with refractive index data), which was comparable to the discrimination powers obtained by LA-ICP-MS and μXRF. These results indicate that LIBS is a feasible alternative to the more expensive LA-ICP-MS and μXRF options for the routine forensic analysis of window glass samples. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A Toddler's Treatment of "Mm" and "Mm Hm" in Talk with a Parent

ERIC Educational Resources Information Center

Filipi, Anna

2007-01-01

The study to be reported in this paper examined the work accomplished by "mm" and "mm hm" in the interactions of a parent and his daughter aged 0;10-2;0. Using the findings of Gardner (2001) for adults, the analysis shows that "mm" accomplished a range of functions based on its sequential placement and prosodic features, whereas "mm hm" was much…

[Effects of Water and Nitrogenous Fertilizer Coupling on CH4 and N2O Emission from Double-Season Rice Paddy Field].

PubMed

Fu, Zhi-qiang; Long, Pan; Liu, Yi-yi; Zhong, Juan; Long, Wen-fei

2015-09-01

To provide support for the efficient use of water and fertilizer technology to double-season rice cultivation, water and fertilizer coupling mode was applied in this research, including two irrigation methods and four N levels. The irrigation methods were flood irrigation and intermittent irrigation, while four N levels were high-N, middle-N, low-N and none-N. Field experiment was conducted to study the effect of water and fertilizer coupling mode on CH4 and N2O emission. The results showed that the accumulated CH4 emissions were significantly reduced by intermittent irrigation, in comparison with flood irrigation, the reduction in early rice season were from 13. 18 kg.hm-2 to 87. 90 kg.hm-2, and were from 74. 48 kg.hm-2 to 131. 07 kg.hm-2 in late rice season, with a rate of 24. 4% -67. 4% and 42. 5% -65. 5% respectively; whereas the accumulated N20 emissions were increased, the increment were from 0. 03 kg.hm-2 to 0. 24 kg.hm-2 in early rice season and from 0. 35 kg.hm-2 to 1. 53 kg.hm-2 in late rice season when compared flood irrigation, increased by 6.2% -18. 3% and 40.2% - 80.9% respectively. On the whole, intermittent irrigation reduces the warming potential of greenhouse gases (GWP), which were decreased by 18. 8% to 58. 6% in early rice season and by 34. 4% to 60. 1% in late rice season, and the reduction of total GWP were from 2 388 to 4 151 kg. hm-2 (CO2 eq), with a rate of 41% -54% . Through correlation analysis it found that CH4 emissions from soil were significantly related with soil solution Eh and solution CH4 concentration. In comparison with the flood irrigation, the application of intermittent irrigation in double-season rice cultivation was conducive to CH4 reduction, though the increase came in N2O, but the GWPs were significantly reduced. Comprehensively, intermittent irrigation matching with middle-N is more benefit to double-season rice cultivation.

Effects of particulate matter exposure on blood 5-hydroxymethylation: results from the Beijing truck driver air pollution study

PubMed Central

Sanchez-Guerra, Marco; Zheng, Yinan; Osorio-Yanez, Citlalli; Zhong, Jia; Chervona, Yana; Wang, Sheng; Chang, Dou; McCracken, John P; Díaz, Anaite; Bertazzi, Pier Alberto; Koutrakis, Petros; Kang, Choong-Min; Zhang, Xiao; Zhang, Wei; Byun, Hyang-Min; Schwartz, Joel; Hou, Lifang; Baccarelli, Andrea A

2015-01-01

Previous studies have reported epigenetic changes induced by environmental exposures. However, previous investigations did not distinguish 5-methylcytosine (5mC) from a similar oxidative form with opposite functions, 5-hydroxymethylcytosine (5hmC). Here, we measured blood DNA global 5mC and 5hmC by ELISA and used adjusted mixed-effects regression models to evaluate the effects of ambient PM10 and personal PM2.5 and its elemental components—black carbon (BC), aluminum (Al), calcium (Ca), potassium (K), iron (Fe), sulfur (S), silicon (Si), titanium (Ti), and zinc (Zn)—on blood global 5mC and 5hmC levels. The study was conducted in 60 truck drivers and 60 office workers in Beijing, China from The Beijing Truck Driver Air Pollution Study at 2 exams separated by one to 2 weeks. Blood 5hmC level (0.08%) was ∼83-fold lower than 5mC (6.61%). An inter-quartile range (IQR) increase in same-day PM10 was associated with increases in 5hmC of 26.1% in office workers (P = 0.004), 20.2% in truck drivers (P = 0.014), and 21.9% in all participants combined (P < 0.001). PM10 effects on 5hmC were increasingly stronger when averaged over 4, 7, and 14 d preceding assessment (up to 132.6% for the 14-d average in all participants, P < 0.001). PM10 effects were also significant after controlling for multiple testing (family-wise error rate; FWER < 0.05). 5hmC was not correlated with personal measures of PM2.5 and elemental components (FWER > 0.05). 5mC showed no correlations with PM10, PM2.5, and elemental components measures (FWER > 0.05). Our study suggests that exposure to ambient PM10 affects 5hmC over time, but not 5mC. This finding demonstrates the need to differentiate 5hmC and 5mC in environmental studies of DNA methylation. PMID:25970091

Early infant adipose deposition is positively associated with the n-6 to n-3 fatty acid ratio in human milk independent of maternal BMI

PubMed Central

Rudolph, Michael C; Young, Bridget E; Lemas, Dominick J; Palmer, Claire E; Hernandez, Teri L; Barbour, Linda A; Friedman, Jacob E; Krebs, Nancy F; MacLean, Paul S

2016-01-01

Background/Objectives Excessive infant weight gain in the first 6-months of life is a powerful predictor of childhood obesity and related health risks. In mice, omega-6 fatty acids (FA) serve as potent ligands driving adipogenesis during early development. The ratio of omega-6 relative to omega-3 (n-6/n-3) FA in human milk (HM) has increased 3-fold over the last 30 years, but the impact of this shift on infant adipose development remains undetermined. This study investigated how maternal obesity and maternal dietary FA (as reflected in maternal red blood cells (RBC) composition) influenced HM n-6 and n-3 FAs, and whether the HM n-6/n-3 ratio was associated with changes in infant adipose deposition between 2-weeks and 4-months postpartum. Subjects/Methods Forty-eight infants from normal-weight (NW), overweight (OW) and obese (OB) mothers were exclusively or predominantly breastfed over the first 4 months of lactation. Mid-feed HM and maternal RBC were collected at either transitional (2-weeks) or established (4-months) lactation, along with infant body composition assessed using air-displacement plethysmography. The FA composition of HM and maternal RBC was measured quantitatively by lipid mass spectrometry. Results In transitional and established HM, DHA was lower (P=0.008; 0.005) and the AA/DHA+EPA ratio was higher (P=0.05; 0.02) in the OB relative to the NW group. Maternal prepregnancy BMI and AA/ DHA+EPA ratios in transitional and established HM were moderately correlated (P=0.018; 0.001). Total infant fat mass was increased in the upper AA/DHA+EPA tertile of established HM relative to the lower tertile (P=0.019). The amount of changes in infant fat mass and % body fat were predicted by AA/EPA+DHA ratios in established HM (P=0.038; 0.010). Conclusions Perinatal infant exposures to a high AA/EPA+DHA ratio during the first 4-months of life, which is primarily reflective of maternal dietary FA, may significantly contribute to the way infants accumulate adipose. PMID:27876761

Speech errors of amnesic H.M.: unlike everyday slips-of-the-tongue.

PubMed

MacKay, Donald G; James, Lori E; Hadley, Christopher B; Fogler, Kethera A

2011-03-01

Three language production studies indicate that amnesic H.M. produces speech errors unlike everyday slips-of-the-tongue. Study 1 was a naturalistic task: H.M. and six controls closely matched for age, education, background and IQ described what makes captioned cartoons funny. Nine judges rated the descriptions blind to speaker identity and gave reliably more negative ratings for coherence, vagueness, comprehensibility, grammaticality, and adequacy of humor-description for H.M. than the controls. Study 2 examined "major errors", a novel type of speech error that is uncorrected and reduces the coherence, grammaticality, accuracy and/or comprehensibility of an utterance. The results indicated that H.M. produced seven types of major errors reliably more often than controls: substitutions, omissions, additions, transpositions, reading errors, free associations, and accuracy errors. These results contradict recent claims that H.M. retains unconscious or implicit language abilities and produces spoken discourse that is "sophisticated," "intact" and "without major errors." Study 3 examined whether three classical types of errors (omissions, additions, and substitutions of words and phrases) differed for H.M. versus controls in basic nature and relative frequency by error type. The results indicated that omissions, and especially multi-word omissions, were relatively more common for H.M. than the controls; and substitutions violated the syntactic class regularity (whereby, e.g., nouns substitute with nouns but not verbs) relatively more often for H.M. than the controls. These results suggest that H.M.'s medial temporal lobe damage impaired his ability to rapidly form new connections between units in the cortex, a process necessary to form complete and coherent internal representations for novel sentence-level plans. In short, different brain mechanisms underlie H.M.'s major errors (which reflect incomplete and incoherent sentence-level plans) versus everyday slips-of-the tongue (which reflect errors in activating pre-planned units in fully intact sentence-level plans). Implications of the results of Studies 1-3 are discussed for systems theory, binding theory and relational memory theories. Copyright © 2010 Elsevier Srl. All rights reserved.

Structure of 5-hydroxymethylcytosine-specific restriction enzyme, AbaSI, in complex with DNA.

PubMed

Horton, John R; Borgaro, Janine G; Griggs, Rose M; Quimby, Aine; Guan, Shengxi; Zhang, Xing; Wilson, Geoffrey G; Zheng, Yu; Zhu, Zhenyu; Cheng, Xiaodong

2014-07-01

AbaSI, a member of the PvuRts1I-family of modification-dependent restriction endonucleases, cleaves deoxyribonucleic acid (DNA) containing 5-hydroxymethylctosine (5hmC) and glucosylated 5hmC (g5hmC), but not DNA containing unmodified cytosine. AbaSI has been used as a tool for mapping the genomic locations of 5hmC, an important epigenetic modification in the DNA of higher organisms. Here we report the crystal structures of AbaSI in the presence and absence of DNA. These structures provide considerable, although incomplete, insight into how this enzyme acts. AbaSI appears to be mainly a homodimer in solution, but interacts with DNA in our structures as a homotetramer. Each AbaSI subunit comprises an N-terminal, Vsr-like, cleavage domain containing a single catalytic site, and a C-terminal, SRA-like, 5hmC-binding domain. Two N-terminal helices mediate most of the homodimer interface. Dimerization brings together the two catalytic sites required for double-strand cleavage, and separates the 5hmC binding-domains by ∼70 Å, consistent with the known activity of AbaSI which cleaves DNA optimally between symmetrically modified cytosines ∼22 bp apart. The eukaryotic SET and RING-associated (SRA) domains bind to DNA containing 5-methylcytosine (5mC) in the hemi-methylated CpG sequence. They make contacts in both the major and minor DNA grooves, and flip the modified cytosine out of the helix into a conserved binding pocket. In contrast, the SRA-like domain of AbaSI, which has no sequence specificity, contacts only the minor DNA groove, and in our current structures the 5hmC remains intra-helical. A conserved, binding pocket is nevertheless present in this domain, suitable for accommodating 5hmC and g5hmC. We consider it likely, therefore, that base-flipping is part of the recognition and cleavage mechanism of AbaSI, but that our structures represent an earlier, pre-flipped stage, prior to actual recognition. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Structure of 5-hydroxymethylcytosine-specific restriction enzyme, AbaSI, in complex with DNA

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

Horton, John R.; Borgaro, Janine G.; Griggs, Rose M.

2014-07-03

AbaSI, a member of the PvuRts1I-family of modification-dependent restriction endonucleases, cleaves DNA containing 5-hydroxymethylctosine (5hmC) and glucosylated 5hmC (g5hmC), but not DNA containing unmodified cytosine. AbaSI has been used as a tool for mapping the genomic locations of 5hmC, an important epigenetic modification in the DNA of higher organisms. Here we report the crystal structures of AbaSI in the presence and absence of DNA. These structures provide considerable, although incomplete, insight into how this enzyme acts. AbaSI appears to be mainly a homodimer in solution, but interacts with DNA in our structures as a homotetramer. Each AbaSI subunit comprises anmore » N-terminal, Vsr-like, cleavage domain containing a single catalytic site, and a C-terminal, SRA-like, 5hmC-binding domain. Two N-terminal helices mediate most of the homodimer interface. Dimerization brings together the two catalytic sites required for double-strand cleavage, and separates the 5hmC binding-domains by ~ 70 Å, consistent with the known activity of AbaSI which cleaves DNA optimally between symmetrically modified cytosines ~ 22 bp apart. The eukaryotic SET and RING-associated (SRA) domains bind to DNA containing 5-methylcytosine (5mC) in the hemi-methylated CpG sequence. They make contacts in both the major and minor DNA grooves, and flip the modified cytosine out of the helix into a conserved binding pocket. In contrast, the SRA-like domain of AbaSI, which has no sequence specificity, contacts only the minor DNA groove, and in our current structures the 5hmC remains intra-helical. A conserved, binding pocket is nevertheless present in this domain, suitable for accommodating 5hmC and g5hmC. We consider it likely, therefore, that base-flipping is part of the recognition and cleavage mechanism of AbaSI, but that our structures represent an earlier, pre-flipped stage, prior to actual recognition.« less

Early infant adipose deposition is positively associated with the n-6 to n-3 fatty acid ratio in human milk independent of maternal BMI.

PubMed

Rudolph, M C; Young, B E; Lemas, D J; Palmer, C E; Hernandez, T L; Barbour, L A; Friedman, J E; Krebs, N F; MacLean, P S

2017-04-01

Excessive infant weight gain in the first 6-month of life is a powerful predictor of childhood obesity and related health risks. In mice, omega-6 fatty acids (FAs) serve as potent ligands driving adipogenesis during early development. The ratio of omega-6 relative to omega-3 (n-6/n-3) FA in human milk (HM) has increased threefold over the last 30 years, but the impact of this shift on infant adipose development remains undetermined. This study investigated how maternal obesity and maternal dietary FA (as reflected in maternal red blood cells (RBCs) composition) influenced HM n-6 and n-3 FAs, and whether the HM n-6/n-3 ratio was associated with changes in infant adipose deposition between 2 weeks and 4 months postpartum. Forty-eight infants from normal weight (NW), overweight (OW) and obese (OB) mothers were exclusively or predominantly breastfed over the first 4 months of lactation. Mid-feed HM and maternal RBC were collected at either transitional (2 weeks) or established (4 months) lactation, along with infant body composition assessed using air-displacement plethysmography. The FA composition of HM and maternal RBC was measured quantitatively by lipid mass spectrometry. In transitional and established HM, docosahexaenoic acid (DHA) was lower (P=0.008; 0.005) and the arachidonic acid (AA)/DHA+eicosapentaenoic acid (EPA) ratio was higher (P=0.05; 0.02) in the OB relative to the NW group. Maternal prepregnancy body mass index (BMI) and AA/DHA+EPA ratios in transitional and established HM were moderately correlated (P=0.018; 0.001). Total infant fat mass was increased in the upper AA/DHA+EPA tertile of established HM relative to the lower tertile (P=0.019). The amount of changes in infant fat mass and percentage of body fat were predicted by AA/EPA+DHA ratios in established HM (P=0.038; 0.010). Perinatal infant exposures to a high AA/EPA+DHA ratio during the first 4 months of life, which is primarily reflective of maternal dietary FA, may significantly contribute to the way infants accumulate adipose.

An indole alkaloid from a tribal folklore inhibits immediate early event in HSV-2 infected cells with therapeutic efficacy in vaginally infected mice.

PubMed

Bag, Paromita; Ojha, Durbadal; Mukherjee, Hemanta; Halder, Umesh Chandra; Mondal, Supriya; Chandra, Nidhi S; Nandi, Suman; Sharon, Ashoke; Sarkar, Mamta Chawla; Chakrabarti, Sekhar; Chattopadhyay, Debprasad

2013-01-01

Herpes genitalis, caused by HSV-2, is an incurable genital ulcerative disease transmitted by sexual intercourse. The virus establishes life-long latency in sacral root ganglia and reported to have synergistic relationship with HIV-1 transmission. Till date no effective vaccine is available, while the existing therapy frequently yielded drug resistance, toxicity and treatment failure. Thus, there is a pressing need for non-nucleotide antiviral agent from traditional source. Based on ethnomedicinal use we have isolated a compound 7-methoxy-1-methyl-4,9-dihydro-3H-pyrido[3,4-b]indole (HM) from the traditional herb Ophiorrhiza nicobarica Balkr, and evaluated its efficacy on isolates of HSV-2 in vitro and in vivo. The cytotoxicity (CC50), effective concentrations (EC50) and the mode of action of HM was determined by MTT, plaque reduction, time-of-addition, immunofluorescence (IFA), Western blot, qRT-PCR, EMSA, supershift and co-immunoprecipitation assays; while the in vivo toxicity and efficacy was evaluated in BALB/c mice. The results revealed that HM possesses significant anti-HSV-2 activity with EC50 of 1.1-2.8 µg/ml, and selectivity index of >20. The time kinetics and IFA demonstrated that HM dose dependently inhibited 50-99% of HSV-2 infection at 1.5-5.0 µg/ml at 2-4 h post-infection. Further, HM was unable to inhibit viral attachment or penetration and had no synergistic interaction with acyclovir. Moreover, Western blot and qRT-PCR assays demonstrated that HM suppressed viral IE gene expression, while the EMSA and co-immunoprecipitation studies showed that HM interfered with the recruitment of LSD-1 by HCF-1. The in vivo studies revealed that HM at its virucidal concentration was nontoxic and reduced virus yield in the brain of HSV-2 infected mice in a concentration dependent manner, compared to vaginal tissues. Thus, our results suggest that HM can serve as a prototype to develop non-nucleotide antiviral lead targeting the viral IE transcription for the management of HSV-2 infections.

Imaging of glutathione localization in brain with technetium-99M meso-hexamethyl propyleneamine oxime

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

Sasaki, T.; Toyama, H.; Oda, K.

1995-05-01

Previous studies have shown decreasing [Tc-99m] meso-HM-PAO uptake in accordance with glutathione (GSH) content in diethyl, maleate (DEM) treated mice brain. In order to elucidate the retention mechanism of [Tc-99m] HM-PAO in brain and to visualize the regional localization of GSH in the brain with [Tc-99m] meso-HM-PAO, the relationship between the tissue GSH content and uptake of [Tc-99m] meso-HM-PAO was studied in rats and rabbits. Increasing pre-load of DEM (550 mg/kg body weight), an agent to reduce GSH content by glutathione transferase, led to a decrease in GSH (control 1.972{plus_minus}0.017 vs DEM 1.138{plus_minus}0.106 mM) and uptake of [Tc-99m] meso-HM-PAO tomore » half of the control in the rat brain (control 0.281{plus_minus}0.024 vs DEM 0.153 {plus_minus} 0.009 % dose/g). On the other hand, the DEM did not decrease GSH or the uptake of [Tc-99m] meso-HM-PAO in the rabbit brain, in which glutathione transferase activity is very low. These results were also demonstrated by images with pin-hole collimated gamma camera. The uptake of [Tc-99m] meso showed variations in the regional distribution, but the d,l-isomer was uniform. [Tc-99m] meso-HM-PAO uptake was well correlated with GSH content in mice brain regions (r=0.800, p<0.02), whereas [Tc-99m]d,l-HM-PAO was not (r=0.017, p>0.5). Both [Tc-99m] mesa HM-PAO uptake and GSH content were especially high at cerebellum (Uptake: 2.598{plus_minus}0.256 % dose/g. GSH: 2.372{plus_minus}0.107 mM) as compared to other areas (Uptake;cerebral cortex 1.797{plus_minus}0.100 brain stem 1.607 {plus_minus}0.112 % dose/g. GSH: cerebral cortex 1.635{plus_minus}0.142 brain stem 1.478{plus_minus}0.141 mM).« less

Herbal Medicine Practices of Patients With Liver Cancer in Peru: A Comprehensive Study Toward Integrative Cancer Management

PubMed Central

Rojas Rojas, Teresa; Bourdy, Geneviève; Ruiz, Eloy; Cerapio, Juan-Pablo; Pineau, Pascal; Gardon, Jacques; Doimi, Franco; Deparis, Xavier; Deharo, Eric; Bertani, Stéphane

2016-01-01

Rationale: The highest burden of liver cancer occurs in developing countries, where the use of herbal medicine (HM) is still widespread. Despite this trend, few studies have been conducted to report HM practices of patients with a hepatic tumor in the developing world. Hence, this study aimed to document the use of HM among patients with liver cancer in Peru. Study Design and Methods: A comparative behavioral epidemiological survey was conducted among liver cancer patients attending the National Cancer Institute of Peru. Information was obtained by direct interviews based on a semistructured questionnaire. The use of HM in Peruvian liver cancer patients was reported, first, regarding general consumption prior to the onset of disease, and second, after the appearance of symptoms that patients would relate to their tumor. In parallel, general consumption of HM in noncancerous people was assessed as a comparative figure. A correspondence analysis was performed to reveal potential associations between the symptoms of cancer and the specific use of HM. Results: Eighty-eight patients and 117 noncancerous individuals participated in the survey. Overall, 68.3% of the people interviewed claimed to use HM on a regular basis for general health preservation. Furthermore, 56.8% of the patients turned to plants first to treat the disorders for which they later came to the cancer care center. When compared with the number of plant species used routinely (n = 78), a selection of plants was made by patients in response to the symptoms of cancer (n = 46). At least 2 plant species, Aloe vera and Morinda citrifolia, were significantly associated with the treatment of liver cancer–related symptoms in the patient group. Conclusions: The present study is the first survey on the HM practices of patients with liver cancer in Latin America and, more broadly, in the developing world. Our findings confirm that HM remains one of the principal primary health care resources in Peru, even for a severe disease like liver cancer. These traditional, complementary and alternative medicine practices should be taken into consideration in Peruvian health programs aiming to educate the population in cancer prevention and treatment, as well as integrative cancer management. PMID:28088871

Partial Least Squares and Neural Networks for Quantitative Calibration of Laser-induced Breakdown Spectroscopy (LIBs) of Geologic Samples

NASA Technical Reports Server (NTRS)

Anderson, R. B.; Morris, Richard V.; Clegg, S. M.; Humphries, S. D.; Wiens, R. C.; Bell, J. F., III; Mertzman, S. A.

2010-01-01

The ChemCam instrument [1] on the Mars Science Laboratory (MSL) rover will be used to obtain the chemical composition of surface targets within 7 m of the rover using Laser Induced Breakdown Spectroscopy (LIBS). ChemCam analyzes atomic emission spectra (240-800 nm) from a plasma created by a pulsed Nd:KGW 1067 nm laser. The LIBS spectra can be used in a semiquantitative way to rapidly classify targets (e.g., basalt, andesite, carbonate, sulfate, etc.) and in a quantitative way to estimate their major and minor element chemical compositions. Quantitative chemical analysis from LIBS spectra is complicated by a number of factors, including chemical matrix effects [2]. Recent work has shown promising results using multivariate techniques such as partial least squares (PLS) regression and artificial neural networks (ANN) to predict elemental abundances in samples [e.g. 2-6]. To develop, refine, and evaluate analysis schemes for LIBS spectra of geologic materials, we collected spectra of a diverse set of well-characterized natural geologic samples and are comparing the predictive abilities of PLS, cascade correlation ANN (CC-ANN) and multilayer perceptron ANN (MLP-ANN) analysis procedures.

Recent Progress in Self-Supported Metal Oxide Nanoarray Electrodes for Advanced Lithium-Ion Batteries.

PubMed

Zhang, Feng; Qi, Limin

2016-09-01

The rational design and fabrication of electrode materials with desirable architectures and optimized properties has been demonstrated to be an effective approach towards high-performance lithium-ion batteries (LIBs). Although nanostructured metal oxide electrodes with high specific capacity have been regarded as the most promising alternatives for replacing commercial electrodes in LIBs, their further developments are still faced with several challenges such as poor cycling stability and unsatisfying rate performance. As a new class of binder-free electrodes for LIBs, self-supported metal oxide nanoarray electrodes have many advantageous features in terms of high specific surface area, fast electron transport, improved charge transfer efficiency, and free space for alleviating volume expansion and preventing severe aggregation, holding great potential to solve the mentioned problems. This review highlights the recent progress in the utilization of self-supported metal oxide nanoarrays grown on 2D planar and 3D porous substrates, such as 1D and 2D nanostructure arrays, hierarchical nanostructure arrays, and heterostructured nanoarrays, as anodes and cathodes for advanced LIBs. Furthermore, the potential applications of these binder-free nanoarray electrodes for practical LIBs in full-cell configuration are outlined. Finally, the future prospects of these self-supported nanoarray electrodes are discussed.

Double-pulse laser-induced breakdown spectroscopy analysis of scales from petroleum pipelines

NASA Astrophysics Data System (ADS)

Cavalcanti, G. H.; Rocha, A. A.; Damasceno, R. N.; Legnaioli, S.; Lorenzetti, G.; Pardini, L.; Palleschi, V.

2013-09-01

Pipeline scales from the Campos Bay Petroleum Field near Rio de Janeiro, Brazil have been analyzed by both Raman spectroscopy and by laser-induced breakdown spectroscopy (LIBS) using a double-pulse, calibration-free approach. Elements that are characteristic of petroleum (e.g. C, H, N, O, Mg, Na, Fe and V) were detected, in addition to the Ca, Al, and Si which form the matrix of the scale. The LIBS results were compared with the results of micro-Raman spectroscopy, which confirmed the nature of the incrustations inferred by the LIBS analysis. Results of this preliminary study suggest that diffusion of pipe material into the pipeline intake column plays an important role in the growth of scale. Thanks to the simplicity and relative low cost of equipment and to the fact that no special chemical pre-treatment of the samples is needed, LIBS can offer very fast acquisition of data and the possibility of in situ measurements. LIBS could thus represent an alternative or complementary method for the chemical characterization of the scales by comparison to conventional analytical techniques, such as X-ray diffraction or X-ray fluorescence.

Feasibility study for detecting copper contaminants in transformer insulation using laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Aparna, N.; Vasa, Nilesh J.; Sarathi, R.; Rajan, J. Sundara

2014-10-01

In recent times, copper sulphide (Cu2S) diffusion in the transformer insulation is a major problem reducing the life of transformers. It is therefore essential to identify a simple methodology to understand the diffusion of Cu2S into the solid insulation [oil impregnated pressboard (OIP)]. In the present work, laser-induced breakdown spectroscopy (LIBS) was adopted to study the diffusion of Cu2S into the pressboard insulation and to determine the depth of diffusion. The diffusion of Cu2S in pressboard was confirmed by electrical discharge studies. In general, flashover voltage and increase in ageing duration of pressboard insulation/Cu concentration had inverse relationship. The characteristic emission lines were also studied through optical emission spectroscopy. Based on LIBS studies with Cu powder dispersed pressboard samples, Cu I emission lines were found to be resolvable up to a lowest concentration of 5 μg/cm2. The LIBS intensity ratio of Cu I-Ca II emission lines were found to increase with increase in the ageing duration of the OIP sample. LIBS studies with OIP samples showed an increase in the optical emission lifetime. LIBS results were in agreement with the electrical discharge studies.

Detection of pesticides and dioxins in tissue fats and rendering oils using laser-induced breakdown spectroscopy (LIBS).

PubMed

Multari, Rosalie A; Cremers, David A; Scott, Thomas; Kendrick, Peter

2013-03-13

In laser-induced breakdown spectroscopy (LIBS), a series of powerful laser pulses are directed at a surface to form microplasmas from which light is collected and spectrally analyzed to identify the surface material. In most cases, no sample preparation is needed, and results can be automated and made available within seconds to minutes. Advances in LIBS spectral data analysis using multivariate regression techniques have led to the ability to detect organic chemicals in complex matrices such as foods. Here, the use of LIBS to differentiate samples contaminated with aldrin, 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin, chlorpyrifos, and dieldrin in the complex matrices of tissue fats and rendering oils is described. The pesticide concentrations in the samples ranged from 0.005 to 0.1 μg/g. All samples were successfully differentiated from each other and from control samples. Sample concentrations could also be differentiated for all of the pesticides and the dioxin included in this study. The results presented here provide first proof-of-principle data for the ability to create LIBS-based instrumentation for the rapid analysis of pesticide and dioxin contamination in tissue fat and rendered oils.

The influence of ns- and fs-LA plume local conditions on the performance of a combined LIBS/LA-ICP-MS sensor

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

LaHaye, Nicole L.; Phillips, Mark C.; Duffin, Andrew M.

2016-01-01

Both laser-induced breakdown spectroscopy (LIBS) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are well-established analytical techniques with their own unique advantages and disadvantages. The combination of the two analytical methods is a very promising way to overcome the challenges faced by each method individually. We made a comprehensive comparison of local plasma conditions between nanosecond (ns) and femtosecond (fs) laser ablation (LA) sources in a combined LIBS and LA-ICP-MS system. The optical emission spectra and ICP-MS signal were recorded simultaneously for both ns- and fs-LA and figures of merit of the system were analyzed. Characterization of the plasma was conductedmore » by evaluating temperature and density of the plume under various irradiation conditions using optical emission spectroscopy, and correlations to ns- and fs-LIBS and LA-ICP-MS signal were made. The present study is very useful for providing conditions for a multimodal system as well as giving insight into how laser ablation plume parameters are related to LA-ICP-MS and LIBS results for both ns- and fs-LA.« less

[Rapid multi-elemental analysis on four precious Tibetan medicines based on LIBS technique].

PubMed

Liu, Xiao-na; Shi, Xin-yuan; Jia, Shuai-yun; Zhao, Na; Wu, Zhi-sheng; Qiao, Yan-jiang

2015-06-01

The laser-induced breakdown spectroscopy (LIBS) was applied to perform a qualitative elementary analysis on four precious Tibetan medicines, i. e. Renqing Mangjue, Renqing Changjue, 25-herb coral pills and 25-herb pearl pills. The specific spectra of the four Tibetan medicines were established. In the experiment, Nd: YAG and 1 064 nm-baseband pulse laser were adopted to collect the spectra. A laser beam focused on the surface of the samples to generate plasma. Its spectral signal was detected by using spectrograph. Based on the National Institute of Standard and Technology (NIST) database, LIBS spectral lines were indentified. The four Tibetan medicines mainly included Ca, Na, K, Mg and other elements and C-N molecular band. Specifically, Fe was detected in Renqing Changjue and 25-herb pearl pills; heavy mental elements Hg and Cu were shown in Renqing Mangjue and Renqing Changjue; Ag was found in Renqing Changjue. The results demonstrated that LIBS is a reliable and rapid multi-element analysis on the four Tibetan medicines. With Real-time, rapid and nondestructive advantages, LIBS has a wide application prospect in the element analysis on ethnic medicines.

Spectroscopic detection of health hazardous contaminants in lipstick using Laser Induced Breakdown Spectroscopy.

PubMed

Gondal, M A; Seddigi, Z S; Nasr, M M; Gondal, B

2010-03-15

Laser Induced Breakdown Spectroscopy (LIBS) technique was applied to determine the concentrations of different toxic elements like lead, chromium, cadmium and zinc in four different lipstick brands sold at local markets in Saudi Arabia. These samples contain toxic elements like lead, cadmium and chromium which are carcinogen dermatitis, allergic and eczematous. Their extraction from human body takes over 40 years and accumulation in the body cause problems like disruption of nervous systems and kidney damage. They could trigger to systemic lupus erythematosus (SLE). In order to test the validity of our LIBS results, standard technique like (ICP-AES) was also applied. To the best of our knowledge, this is the first study where LIBS technique was applied for the measurement of toxic substances in lipsticks. The maximum concentration detected in four lipstick brands was much higher than the permissible safe limits for human use and could lead to serious health problems. It is worth mentioning that the lipstick is not a solid rather is in fluid state which is not trivial to analyze using LIBS technique. For this purpose, special treatment of the lipstick samples was necessary to analyze with our LIBS method. (c) 2009 Elsevier B.V. All rights reserved.

Dynamic heterogeneity of DNA methylation and hydroxymethylation in embryonic stem cell populations captured by single-cell 3D high-content analysis.

PubMed

Tajbakhsh, Jian; Stefanovski, Darko; Tang, George; Wawrowsky, Kolja; Liu, Naiyou; Fair, Jeffrey H

2015-03-15

Cell-surface markers and transcription factors are being used in the assessment of stem cell fate and therapeutic safety, but display significant variability in stem cell cultures. We assessed nuclear patterns of 5-hydroxymethylcytosine (5hmC, associated with pluripotency), a second important epigenetic mark, and its combination with 5-methylcytosine (5mC, associated with differentiation), also in comparison to more established markers of pluripotency (Oct-4) and endodermal differentiation (FoxA2, Sox17) in mouse embryonic stem cells (mESC) over a 10-day differentiation course in vitro: by means of confocal and super-resolution imaging together with 3D high-content analysis, an essential tool in single-cell screening. 1) We did not measure any significant correlation of putative markers with global 5mC or 5hmC. 2) While average Oct-4 levels stagnated on a cell-population base (0.015 lnIU/day), Sox17 and FoxA2 increased 22-fold and 3-fold faster, respectively (Sox17: 0.343 lnIU/day; FoxA2: 0.046 lnIU/day). In comparison, global DNA methylation levels increased 4-fold faster (0.068 lnIU/day), and global hydroxymethylation declined at 0.046 lnIU/day, both with a better explanation of the temporal profile. 3) This progression was concomitant with the occurrence of distinct nuclear codistribution patterns that represented a heterogeneous spectrum of states in differentiation; converging to three major coexisting 5mC/5hmC phenotypes by day 10: 5hmC(+)/5mC(-), 5hmC(+)/5mC(+), and 5hmC(-)/5mC(+) cells. 4) Using optical nanoscopy we could delineate the respective topologies of 5mC/5hmC colocalization in subregions of nuclear DNA: in the majority of 5hmC(+)/5mC(+) cells 5hmC and 5mC predominantly occupied mutually exclusive territories resembling euchromatic and heterochromatic regions, respectively. Simultaneously, in a smaller subset of cells we observed a tighter colocalization of the two cytosine variants, presumably delineating chromatin domains in remodeling. We conclude that 1) 5mC emerges as the most differential marker in our model system. 2) However, the combined enrollment of the two DNA modifications provided higher-definition screening and lead to the identification of cell subpopulations based on differential 5hmC/5mC phenotypes corresponding to different 5hmC/5mC ratios. The results encourage: a) assessing the regenerative potential of early-endodermal cells enriched for the three DNA methylation/hydroxymethylation categories, and b) exploring the universality of this type of epigenetic phenotyping across other lineage-specific differentiations. Copyright © 2015 Elsevier Inc. All rights reserved.

SPECT measurements with /sup 99m/Tc-HM-PAO in focal epilepsy

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

Ryding, E.; Rosen, I.; Elmqvist, D.

1988-12-01

The ability of SPECT measurements with (/sup 99m/Tc)-HM-PAO (Ceretec) to find the location of the epileptic focus was studied in patients under consideration for neurosurgical treatment for therapy-resistant focal epilepsy. The location of low (/sup 99m/Tc)-HM-PAO uptake regions found at interictal measurements, and of high (/sup 99m/Tc)-HM-PAO uptake regions found at ictal measurements, was compared to the findings of extensive ictal and interictal EEG examinations, and to the results of CT and MRT. While EEG revealed focal epileptic activity in all of the 14 patients, SPECT showed regional abnormalities in 13 (93%). CT and MRT showed abnormal findings in 30%.

Photochemistry of Iron and Ruthenium Carbonyl Complexes: Evidence for Light-Induced Loss of Carbon Monoxide and Reductive Elimination of Triethylsilane from cis-mer-HM(SiEt3)(CO)3(PPh3).

DTIC Science & Technology

1983-05-21

JEOL FX9OQ Fourier transform or Bruker 250 or 270 MHz Fourier transform spectrometer. Irradiations. Photochemical reactions were carried out using a...Ph 3 ) 3nd -t-Etin V,- a 313 nm quantum yield of -0.6. The process is photochemically everse if the cis-mer-HM(SiPh 3 )(CO) 3 (PPh 3) is irradiated...process is photochemically reversed if the cis-mer-HM(SiPh 3 )(CO)3 (PPh 3 ) is irradiated in t.e presence of excess Et3SiH. Irradiation of cis-mer-HM

Carbohydrate-protein interactions investigated on plastic chips statically coated with hydrophobically modified hydroxyethylcellulose.

PubMed

Dang, Fuquan; Maeda, Eiki; Osafune, Tomo; Nakajima, Kazuki; Kakehi, Kazuaki; Ishikawa, Mitsuru; Baba, Yoshinobu

2009-12-15

We developed a novel method for rapid screening of carbohydrate-protein interactions using poly(methyl methacrylate) (PMMA) channels statically coated with hydrophobically modified hydroxyethylcellulose (HM-HEC). We found that a self-assembled monolayer (SAM) of HM-HEC on a PMMA surface intact by water allows rapid and reproducible separations of glycan samples using a 20 mM phosphate without HM-HEC. The underlying mechanism for dynamic and static coatings on the PMMA surface is discussed. Simultaneous analysis of the molecular interaction between a complex mixture of carbohydrates from alpha1-acid glycoprotein and proteins has been successfully achieved in PMMA channels statically coated with a SAM of HM-HEC.

Dynamic heterogeneity of DNA methylation and hydroxymethylation in embryonic stem cell populations captured by single-cell 3D high-content analysis

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

Tajbakhsh, Jian, E-mail: tajbakhshj@cshs.org; Translational Cytomics Group, Cedars-Sinai Medical Center, Los Angeles, CA 90048; Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048

2015-03-15

Cell-surface markers and transcription factors are being used in the assessment of stem cell fate and therapeutic safety, but display significant variability in stem cell cultures. We assessed nuclear patterns of 5-hydroxymethylcytosine (5hmC, associated with pluripotency), a second important epigenetic mark, and its combination with 5-methylcytosine (5mC, associated with differentiation), also in comparison to more established markers of pluripotency (Oct-4) and endodermal differentiation (FoxA2, Sox17) in mouse embryonic stem cells (mESC) over a 10-day differentiation course in vitro: by means of confocal and super-resolution imaging together with 3D high-content analysis, an essential tool in single-cell screening. In summary: 1) Wemore » did not measure any significant correlation of putative markers with global 5mC or 5hmC. 2) While average Oct-4 levels stagnated on a cell-population base (0.015 lnIU/day), Sox17 and FoxA2 increased 22-fold and 3-fold faster, respectively (Sox17: 0.343 lnIU/day; FoxA2: 0.046 lnIU/day). In comparison, global DNA methylation levels increased 4-fold faster (0.068 lnIU/day), and global hydroxymethylation declined at 0.046 lnIU/day, both with a better explanation of the temporal profile. 3) This progression was concomitant with the occurrence of distinct nuclear codistribution patterns that represented a heterogeneous spectrum of states in differentiation; converging to three major coexisting 5mC/5hmC phenotypes by day 10: 5hmC{sup +}/5mC{sup −}, 5hmC{sup +}/5mC{sup +}, and 5hmC{sup −}/5mC{sup +} cells. 4) Using optical nanoscopy we could delineate the respective topologies of 5mC/5hmC colocalization in subregions of nuclear DNA: in the majority of 5hmC{sup +}/5mC{sup +} cells 5hmC and 5mC predominantly occupied mutually exclusive territories resembling euchromatic and heterochromatic regions, respectively. Simultaneously, in a smaller subset of cells we observed a tighter colocalization of the two cytosine variants, presumably delineating chromatin domains in remodeling. We conclude that 1) 5mC emerges as the most differential marker in our model system. 2) However, the combined enrollment of the two DNA modifications provided higher-definition screening and lead to the identification of cell subpopulations based on differential 5hmC/5mC phenotypes corresponding to different 5hmC/5mC ratios. The results encourage: a) assessing the regenerative potential of early-endodermal cells enriched for the three DNA methylation/hydroxymethylation categories, and b) exploring the universality of this type of epigenetic phenotyping across other lineage-specific differentiations. - Highlights: • First reported single-molecule super-resolution 3D-visualization of 5mC/5hmC sites in cells. • Identification of cells with differential 5mC/5hmC nuclear codistribution phenotypes. • Application of principle component and robust regression analyses for evaluation of 3D high-content-screening data. • Global 5mC constitutes a highly differential spatiotemporal in situ marker in early endodermal cell differentiation.« less

PV_LIB Toolbox v. 1.3

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

2015-12-09

PV_LIB comprises a library of Matlab? code for modeling photovoltaic (PV) systems. Included are functions to compute solar position and to estimate irradiance in the PV system's plane of array, cell temperature, PV module electrical output, and conversion from DC to AC power. Also included are functions that aid in determining parameters for module performance models from module characterization testing. PV_LIB is open source code primarily intended for research and academic purposes. All algorithms are documented in openly available literature with the appropriate references included in comments within the code.

A bioinformatics transcriptome meta-analysis highlights the importance of trophoblast differentiation in the pathology of hydatidiform moles.

PubMed

Desterke, Christophe; Slim, Rima; Candelier, Jean-Jacques

2018-05-01

Hydatidiform mole (HM) is an aberrant human pregnancy with abnormal trophoblastic development, migration/invasion of the extravillous trophoblast in the decidua. These abnormalities are established in a hypoxic environment during the first trimester of gestation. Using text mining, we identified 72 unique genes that are linked to HM (HM-linked genes) that we studied by bioinformatic analysis in publicly available transcriptomes of primary chorionic villous cells (cytotrophoblast, syncytiotrophoblast, extravillous trophoblast, and arterial and venous endothelial) isolated from normal placentas or established trophoblastic cell lines cultured under different oxygen concentrations. We show that the majority of HM-linked genes (75%) are involved in normal trophoblastic differentiation, arranged in clusters, and some of them are implicated in chorionic villous invasion or regulated by oxygen concentrations. Our analysis integrates the various aspects of the pathophysiology of HM and highlights the importance of trophoblastic differentiation in this pathology. Copyright © 2018 Elsevier Ltd. All rights reserved.

Nature and distribution of potential heavy-mineral resources offshore of the Atlantic Coast of the United States.

USGS Publications Warehouse

Grosz, A.E.

1987-01-01

The US is dependent on foreign imports of placer heavy minerals for a majority of its ilmenite and rutile, and virtually all of its monazite requirements. Although sand deposits in the SE US are important domestic sources of these heavy minerals (HM) and a number of other less well-known heavy-mineral species, global onshore reserves of placer minerals may fall short of demand in as few as 20 years. Insofar as they are important commodities for the future, offshore HM placers will become more important, but much research on them remains to be done. Results of recent offshore studies, based on surficial grab samples, indicate an average of about 2 weight percent HM in surficial Atlantic Continental Shelf (ACS) sediments, in strong contrast with previous estimates of an average of 0.16% HM. Although provocative, the information from these grab samples does not include the thickness of the HM deposits and thus their volume and tonnage cannot be estimated.-from Author

HM{sup +} and HM{sup +}‑He (M = Group 2 metal): Chemical or physical interactions?

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

Harris, Joe P.; Dodson, Hannah; Wright, Timothy G., E-mail: Tim.Wright@nottingham.ac.uk

2014-09-07

We investigate the HM{sup +}‑He complexes (M = Group 2 metal) using quantum chemistry. Equilibrium geometries are linear for M = Be and Mg, and bent for M = Ca–Ra; the explanation for this lies in the differing nature of the highest occupied molecular orbitals in the two sets of complexes. The difference primarily occurs as a result of the formation of the H–M{sup +} bond, and so the HM{sup +} diatomics are also studied as part of the present work. The position of the He atom in the complexes is largely determined by the form of the electron density.more » HM{sup +}…He binding energies are obtained and are surprisingly high for a helium complex. The HBe{sup +}…He value is almost 3000 cm{sup −1}, which is high enough to suspect contributions from chemical bonding. This is explored by examining the natural orbital density and by population analyses.« less

Final Technical Report

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

Stoessel, Chris

2013-11-13

This project developed a new high-performance R-10/high SHGC window design, reviewed market positioning and evaluated manufacturing solutions required for broad market adoption. The project objectives were accomplished by: identifying viable technical solutions based on modeling of modern and potential coating stacks and IGU designs; development of new coating material sets for HM thin film stacks, as well as improved HM IGU designs to accept multiple layers of HM films; matching promising new coating designs with new HM IGU designs to demonstrate performance gains; and, in cooperation with a window manufacturer, assess the potential for high-volume manufacturing and cost efficiency ofmore » a HM-based R-10 window with improved solar heat gain characteristics. A broad view of available materials and design options was applied to achieve the desired improvements. Gated engineering methodologies were employed to guide the development process from concept generation to a window demonstration. The project determined that a slightly de-rated window performance allows formulation of a path to achieve the desired cost reductions to support end consumer adoption.« less

Dynamic changes in DNA demethylation in the tree shrew (Tupaia belangeri chinensis) brain during postnatal development and aging.

PubMed

Wei, Shu; Hua, Hai-Rong; Chen, Qian-Quan; Zhang, Ying; Chen, Fei; Li, Shu-Qing; Li, Fan; Li, Jia-Li

2017-03-18

Brain development and aging are associated with alterations in multiple epigenetic systems, including DNA methylation and demethylation patterns. Here, we observed that the levels of the 5-hydroxymethylcytosine (5hmC) ten-eleven translocation (TET) enzyme-mediated active DNA demethylation products were dynamically changed and involved in postnatal brain development and aging in tree shrews ( Tupaia belangeri chinensis ). The levels of 5hmC in multiple anatomic structures showed a gradual increase throughout postnatal development, whereas a significant decrease in 5hmC was found in several brain regions in aged tree shrews, including in the prefrontal cortex and hippocampus, but not the cerebellum. Active changes in Tet mRNA levels indicated that TET2 and TET3 predominantly contributed to the changes in 5hmC levels. Our findings provide new insight into the dynamic changes in 5hmC levels in tree shrew brains during postnatal development and aging processes.

Purification, structural characterization and anticoagulant properties of fucosylated chondroitin sulfate isolated from Holothuria mexicana.

PubMed

Mou, Jiaojiao; Wang, Cong; Li, Wenjing; Yang, Jie

2017-05-01

A novel fucosylated chondroitin sulfate (HmG) was isolated from sea cucumber Holothuria mexicana, the structure of which was characterized by monosaccharide composition, disaccharide composition, IR, 1 H and 13 C NMR spectrum, additionally with two dimensional NMR spectrum of degraded HmG (DHmG). The backbone of HmG was identified as chondroitin 6-O sulfate, while the major O-4 sulfated fucose branches linked to O-3 position of glucuronic acid in almost every disaccharide unit. The anticoagulant activities of HmG and DHmG were assessed and compared with heparin and low molecular weight heparin. The results indicated that HmG and DHmG both could significantly prolong the activated partial thrombo-plastin time, and the properties were well related to its molecular weight. DHmG showed similar anticoagulant properties to low molecular weight heparin with less bleeding risks, making it a safer anticoagulant drug. Copyright © 2017 Elsevier B.V. All rights reserved.

Plant-driven removal of heavy metals from soil: uptake, translocation, tolerance mechanism, challenges, and future perspectives.

PubMed

Thakur, Sveta; Singh, Lakhveer; Wahid, Zularisam Ab; Siddiqui, Muhammad Faisal; Atnaw, Samson Mekbib; Din, Mohd Fadhil Md

2016-04-01

Increasing heavy metal (HM) concentrations in the soil have become a significant problem in the modern industrialized world due to several anthropogenic activities. Heavy metals (HMs) are non-biodegradable and have long biological half lives; thus, once entered in food chain, their concentrations keep on increasing through biomagnification. The increased concentrations of heavy metals ultimately pose threat on human life also. The one captivating solution for this problem is to use green plants for HM removal from soil and render it harmless and reusable. Although this green technology called phytoremediation has many advantages over conventional methods of HM removal from soils, there are also many challenges that need to be addressed before making this technique practically feasible and useful on a large scale. In this review, we discuss the mechanisms of HM uptake, transport, and plant tolerance mechanisms to cope with increased HM concentrations. This review article also comprehensively discusses the advantages, major challenges, and future perspectives of phytoremediation of heavy metals from the soil.

Design and Analysis of a Hyperspectral Microwave Receiver Subsystem

NASA Technical Reports Server (NTRS)

Blackwell, W.; Galbraith, C.; Hancock, T.; Leslie, R.; Osaretin, I.; Shields, M.; Racette, P.; Hillard, L.

2012-01-01

Hyperspectral microwave (HM) sounding has been proposed to achieve unprecedented performance. HM operation is achieved using multiple banks of RF spectrometers with large aggregate bandwidth. A principal challenge is Size/Weight/Power scaling. Objectives of this work: 1) Demonstrate ultra-compact (100 cm3) 52-channel IF processor (enabler); 2) Demonstrate a hyperspectral microwave receiver subsystem; and 3) Deliver a flight-ready system to validate HM sounding.

Comparison of acoustic fields produced by the original and upgraded HM-3 lithotripter

NASA Astrophysics Data System (ADS)

Zhou, Yufeng; Zhu, Songlin; Dreyer, Thomas; Liebler, Marko; Zhong, Pei

2003-10-01

To reduce tissue injury in shock wave lithotripsy (SWL) while maintaining satisfactory stone comminution, an original HM-3 lithotripter was upgraded by a reflector insert to suppress large intraluminal bubble expansion, which is a primary mechanism of vascular injury in SWL. The pressure waveforms produced by the original and upgraded HM-3 lithotripter were measured by using a fiber optical probe hydrophone (FOPH), which was scanned both along and transverse to the lithotripter axis at 1-mm step using a computer-controlled 3-D positioning system. At F2, the pressure waveform produced by the upgraded HM-3 lithotripter at 22 kV has a distinct dual-pulse structure, with a leading shock wave of ~45 MPa from the reflector insert and a 4-μs delayed second pulse of ~15 MPa reflected from the uncovered bottom surface of the original HM-3 reflector. The beam sizes of the original and upgraded HM-3 lithotripter are comparable in both axial and lateral directions. The pressure waveforms measured at the reflector aperture will be used as input to the KZK equation to predict the lithotripter shock wave at F2. Furthermore, bubble dynamics predicted by the Gilmore model will be compared with experimental observation by high-speed imaging. [Work supported by NIH.

[Effects of different water and fertilizer supply on cucumber soil nutrient content, enzyme activity, and microbial diversity].

PubMed

Wei, Ze-Xiu; Liang, Yin-Li; Inoue, Mitsuhiro; Zhou, Mao-Juan; Huang, Mao-Lin; Gu, Jian-Feng; Wu, Yan

2009-07-01

With cucumber (Cucumis sativus L.) variety Jinyou 1 as test material, a greenhouse experiment was conducted to study the effects of different water and fertilizer supply on the cucumber soil nutrient content, enzyme activity, and microbial diversity. Three water regimes (50%-60%, 70%-80%, and 90%-100% soil relative moisture content) and two fertilization practices (600 kg N x hm(-2) + 420 kg P2O5 x hm(-2) and 420 kg N x hm(-2) + 294 kg P2O5 x hm(-2)) were designed. The increase of water and fertilizer supply benefited the increase of soil available P content and sucrase activity. Increasing fertilization rate increased soil NH(4+)-N content but decreased soil protease activity, and increasing soil relative moisture content decreased the soil NH(4+)-N content and urease activity. Soil microbial diversity had no significant correlations with soil nutrient contents, but significantly positively correlated with soil urease activity and negatively correlated with soil sucrase activity. Among the treatments, the treatment 70%-80% soil relative moisture content + 600 kg N x hm(-2) and 420 kg P2O5 x hm(-2) had the highest soil nutrient contents, soil urease, sucrase, and phosphatase activities, and soil microbial diversity and evenness, being the best in soil potential productivity.

Pesticides in human milk of Western Australian women and their influence on infant growth outcomes: A cross-sectional study.

PubMed

Du, Jian; Gridneva, Zoya; Gay, Melvin C L; Trengove, Robert D; Hartmann, Peter E; Geddes, Donna T

2017-01-01

Persistent organic pollutants in human milk (HM) at high levels are considered to be detrimental to the breastfed infant. To determine the pesticide concentration in HM, a pilot cross-sectional study of 40 Western Australian (WA) women was carried out. Gas chromatography-tandem mass spectrometry (GC-MS/MS) with a validated QuEChERS was used for the analysis of 88 pesticides in HM. p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) with a mean concentration of 62.8 ± 54.5 ng/g fat was found, whereas other organochlorines, organophosphates, carbamates and pyrethroids were not detected in HM. Overall, no association was observed between HM p,p'-DDE concentrations and maternal age, parity, body mass index and percentage fat mass. Furthermore, for the first time no significant association was found between p,p'-DDE concentrations in HM and infant growth outcomes such as weight, length, head circumference and percentage fat mass. The calculated daily intake was significantly different to the estimated daily intake of total DDTs and was well below the guideline proposed by WHO. The DDTs levels in WA have also significantly decreased by 42 - fold since the 1970s and are currently the lowest in Australia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bioactive peptides released from in vitro digestion of human milk with or without pasteurization.

PubMed

Wada, Yasuaki; Lönnerdal, Bo

2015-04-01

Pasteurized donor human milk (HM) serves as the best alternative for breast-feeding when availability of mother's milk is limited. Pasteurization is also applied to mother's own milk for very low birth weight infants, who are vulnerable to microbial infection. Whether pasteurization affects protein digestibility and therefore modulates the profile of bioactive peptides released from HM proteins by gastrointestinal digestion, has not been examined to date. HM with and without pasteurization (62.5 °C for 30 min) were subjected to in vitro gastrointestinal digestion, followed by peptidomic analysis to compare the formation of bioactive peptides. Some of the bioactive peptides, such as caseinophosphopeptide homologues, a possible opioid peptide (or propeptide), and an antibacterial peptide, were present in undigested HM and showed resistance to in vitro digestion, suggesting that these peptides are likely to exert their bioactivities in the gastrointestinal lumen, or be stably transported to target organs. In vitro digestion of HM released a large variety of bioactive peptides such as angiotensin I-converting enzyme-inhibitory, antioxidative, and immunomodulatory peptides. Bioactive peptides were released largely in the same manner with and without pasteurization. Provision of pasteurized HM may be as beneficial as breast-feeding in terms of milk protein-derived bioactive peptides.

Short-range correlation in high-momentum antisymmetrized molecular dynamics

NASA Astrophysics Data System (ADS)

Myo, Takayuki

2018-03-01

We propose a new variational method for treating short-range repulsion of bare nuclear force for nuclei in antisymmetrized molecular dynamics (AMD). In AMD, the short-range correlation is described in terms of large imaginary centroids of Gaussian wave packets of nucleon pairs in opposite signs, causing high-momentum components in the nucleon pairs. We superpose these AMD basis states and call this method "high-momentum AMD" (HM-AMD), which is capable of describing the strong tensor correlation [T. Myo et al., Prog. Theor. Exp. Phys., 2017, 111D01 (2017)]. In this letter, we extend HM-AMD by including up to two kinds of nucleon pairs in each AMD basis state utilizing the cluster expansion, which produces many-body correlations involving high-momentum components. We investigate how well HM-AMD describes the short-range correlation by showing the results for ^3H using the Argonne V4^' central potential. It is found that HM-AMD reproduces the results of few-body calculations and also the tensor-optimized AMD. This means that HM-AMD is a powerful approach to describe the short-range correlation in nuclei. In HM-AMD, the momentum directions of nucleon pairs isotropically contribute to the short-range correlation, which is different from the tensor correlation.

ImgLib2--generic image processing in Java.

PubMed

Pietzsch, Tobias; Preibisch, Stephan; Tomancák, Pavel; Saalfeld, Stephan

2012-11-15

ImgLib2 is an open-source Java library for n-dimensional data representation and manipulation with focus on image processing. It aims at minimizing code duplication by cleanly separating pixel-algebra, data access and data representation in memory. Algorithms can be implemented for classes of pixel types and generic access patterns by which they become independent of the specific dimensionality, pixel type and data representation. ImgLib2 illustrates that an elegant high-level programming interface can be achieved without sacrificing performance. It provides efficient implementations of common data types, storage layouts and algorithms. It is the data model underlying ImageJ2, the KNIME Image Processing toolbox and an increasing number of Fiji-Plugins. ImgLib2 is licensed under BSD. Documentation and source code are available at http://imglib2.net and in a public repository at https://github.com/imagej/imglib. Supplementary data are available at Bioinformatics Online. saalfeld@mpi-cbg.de

Post-mortem characterization of fs laser-generated micro-pillars in Li(Ni1/3Mn1/3Co1/3)O2 electrodes by laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Smyrek, P.; Zheng, Y.; Seifert, H. J.; Pfleging, W.

2016-03-01

NMC thick films were prepared by tape-casting and subsequent ultrafast laser-structuring. The lithium distribution in electrochemically cycled and unstructured or fs laser-structured NMC cathodes was investigated by using Laser-Induced Breakdown Spectroscopy (LIBS). The main goal is to develop an optimized three dimensional cell architecture with improved electrochemical properties based on studies of the homogeneity of the local State-of-Charge. LIBS experiments were carried out using a LIBS workstation equipped with a mode-locked diode pumped solid state Nd:YAG laser operating at a wavelength of 1063 nm. The element distribution was investigated using two different techniques: element mapping and element depth-profiling of the unstructured / fs laser-structured electrode surface. Results achieved from post-mortem studies using LIBS will be presented.

Recent Progresses and Development of Advanced Atomic Layer Deposition towards High-Performance Li-Ion Batteries

PubMed Central

Lu, Wei; Liang, Longwei; Sun, Xuan; Sun, Xiaofei; Wu, Chen; Hou, Linrui; Sun, Jinfeng

2017-01-01

Electrode materials and electrolytes play a vital role in device-level performance of rechargeable Li-ion batteries (LIBs). However, electrode structure/component degeneration and electrode-electrolyte sur-/interface evolution are identified as the most crucial obstacles in practical applications. Thanks to its congenital advantages, atomic layer deposition (ALD) methodology has attracted enormous attention in advanced LIBs. This review mainly focuses upon the up-to-date progress and development of the ALD in high-performance LIBs. The significant roles of the ALD in rational design and fabrication of multi-dimensional nanostructured electrode materials, and finely tailoring electrode-electrolyte sur-/interfaces are comprehensively highlighted. Furthermore, we clearly envision that this contribution will motivate more extensive and insightful studies in the ALD to considerably improve Li-storage behaviors. Future trends and prospects to further develop advanced ALD nanotechnology in next-generation LIBs were also presented. PMID:29036916

Internal-short-mitigating current collector for lithium-ion battery

NASA Astrophysics Data System (ADS)

Wang, Meng; Le, Anh V.; Noelle, Daniel J.; Shi, Yang; Meng, Y. Shirley; Qiao, Yu

2017-05-01

Mechanical abuse often causes thermal runaway of lithium-ion battery (LIB). When a LIB cell is impacted, radial cracks can be formed in the current collector, separating the electrode into petals. As separator ruptures, the petals on positive and negative electrodes may contact each other, forming internal short circuit (ISC). In this study, we conducted an experimental investigation on LIB coin cells with current collectors modified by surface notches. Our testing results showed that as the current collector contained appropriate surface notches, the cracking mode of electrode in a damaged LIB cell could be adjusted. Particularly, if a complete circumferential crack was generated, the petals would be cut off, which drastically reduced the area of electrode involved in ISC and the associated heat generation rate. A parameterized study was performed to analysis various surface-notch configurations. We identified an efficient surface-notch design that consistently led to trivial temperature increase of ISC.

[Study on physical deviation factors on laser induced breakdown spectroscopy measurement].

PubMed

Wan, Xiong; Wang, Peng; Wang, Qi; Zhang, Qing; Zhang, Zhi-Min; Zhang, Hua-Ming

2013-10-01

In order to eliminate the deviation between the measured LIBS spectral line and the standard LIBS spectral line, and improve the accuracy of elements measurement, a research of physical deviation factors in laser induced breakdown spectroscopy technology was proposed. Under the same experimental conditions, the relationship of ablated hole effect and spectral wavelength was tested, the Stark broadening data of Mg plasma laser induced breakdown spectroscopy with sampling time-delay from 1.00 to 3.00 micros was also studied, thus the physical deviation influences such as ablated hole effect and Stark broadening could be obtained while collecting the spectrum. The results and the method of the research and analysis can also be applied to other laser induced breakdown spectroscopy experiment system, which is of great significance to improve the accuracy of LIBS elements measuring and is also important to the research on the optimum sampling time-delay of LIBS.

Nanotechnology for environmentally sustainable electromobility

NASA Astrophysics Data System (ADS)

Ellingsen, Linda Ager-Wick; Hung, Christine Roxanne; Majeau-Bettez, Guillaume; Singh, Bhawna; Chen, Zhongwei; Whittingham, M. Stanley; Strømman, Anders Hammer

2016-12-01

Electric vehicles (EVs) powered by lithium-ion batteries (LIBs) or proton exchange membrane hydrogen fuel cells (PEMFCs) offer important potential climate change mitigation effects when combined with clean energy sources. The development of novel nanomaterials may bring about the next wave of technical improvements for LIBs and PEMFCs. If the next generation of EVs is to lead to not only reduced emissions during use but also environmentally sustainable production chains, the research on nanomaterials for LIBs and PEMFCs should be guided by a life-cycle perspective. In this Analysis, we describe an environmental life-cycle screening framework tailored to assess nanomaterials for electromobility. By applying this framework, we offer an early evaluation of the most promising nanomaterials for LIBs and PEMFCs and their potential contributions to the environmental sustainability of EV life cycles. Potential environmental trade-offs and gaps in nanomaterials research are identified to provide guidance for future nanomaterial developments for electromobility.

Application of LIBS and TMA for the determination of combustion predictive indices of coals and coal blends

NASA Astrophysics Data System (ADS)

Ctvrtnickova, T.; Mateo, M. P.; Yañez, A.; Nicolas, G.

2011-04-01

Presented work brings results of Laser-Induced Breakdown Spectroscopy (LIBS) and Thermo-Mechanical Analysis (TMA) of coals and coal blends used in coal fired power plants all over Spain. Several coal specimens, its blends and corresponding laboratory ash were analyzed by mentioned techniques and results were compared to standard laboratory methods. The indices of slagging, which predict the tendency of coal ash deposition on the boiler walls, were determined by means of standard chemical analysis, LIBS and TMA. The optimal coal suitable to be blended with the problematic national lignite coal was suggested in order to diminish the slagging problems. Used techniques were evaluated based on the precision, acquisition time, extension and quality of information they could provide. Finally, the applicability of LIBS and TMA to the successful calculation of slagging indices is discussed and their substitution of time-consuming and instrumentally difficult standard methods is considered.

Preliminary study on detection sediment contamination in soil affected by the Indian Ocean giant tsunami 2004 in Aceh, Indonesia using laser-induced breakdown spectroscopy (LIBS)

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

Idris, Nasrullah, E-mail: nasrullah.idris@unsyiah.ac.id; Ramli, Muliadi; Hedwig, Rinda

This work is intended to asses the capability of LIBS for the detection of the tsunami sediment contamination in soil. LIBS apparatus used in this work consist of a laser system and an optical multichannel analyzer (OMA) system. The soil sample was collected from in Banda Aceh City, Aceh, Indonesia, the most affected region by the giant Indian Ocean tsunami 2004. The laser beam was focused onto surface of the soil pellet using a focusing lens to produce luminous plasma. The experiment was conducted under air as surrounding gas at 1 atmosphere. The emission spectral lines from the plasma weremore » detected by the OMA system. It was found that metal including heavy metals can surely be detected, thus implying the potent of LIBS technique as a fast screening tools of tsunami sediment contamination.« less

Study of atomic and molecular emission spectra of Sr by laser induced breakdown spectroscopy (LIBS).

PubMed

Bhatt, Chet R; Alfarraj, Bader; Ayyalasomayajula, Krishna K; Ghany, Charles; Yueh, Fang Y; Singh, Jagdish P

2015-12-01

Laser Induced Breakdown Spectroscopy (LIBS) is an ideal analytical technique for in situ analysis of elemental composition. We have performed a comparative study of the quantitative and qualitative analysis of atomic and molecular emission from LIBS spectra. In our experiments, a mixture of SrCl2 and Al2O3 in powder form was used as a sample. The atomic emission from Sr and molecular emission from SrCl and SrO observed in LIBS spectra were analyzed. The optimum laser energies, gate delays, and gate widths for selected atomic lines and molecular bands were determined from spectra recorded at various experimental parameters. These optimum experimental conditions were used to collect calibration data, and the calibration curves were used to predict the Sr concentration. Limits of detection (LODs) for selected atomic and molecular emission spectra were determined.

Direct Determination of Contaminants and Major and Minor Nutrients in Solid Fertilizers Using Laser-Induced Breakdown Spectroscopy (LIBS).

PubMed

Andrade, Daniel F; Pereira-Filho, Edenir Rodrigues

2016-10-11

Contaminants (Cd, Cr, and Pb) as well as minor (B, Cu, Mn, Na, and Zn) and major (Ca and Mg) elements were directly determined in solid fertilizer samples using laser-induced breakdown spectroscopy (LIBS). Factorial designs were used to define the most appropriate LIBS parameters and pellet pressure on solid fertilizers. Emission lines for all of the analytes were collected and employed 12 signal normalization modes. The best results were obtained using a laser energy of 75 mJ, a spot size of 50 μm, a pressure of 10 t/in., and a delay of 2.0 μs. Good correlation was obtained between the calibration model's prediction using the proposed LIBS method and the reference values obtained with ICP-OES. The limits of detection (LOD) for the proposed method varied from 2 mg/kg (for Cd) to 1% (for Zn).

Investigations of calcium spectral lines in laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Ching, Sim Yit; Tariq, Usman; Haider, Zuhaib; Tufail, Kashif; Sabri, Salwanie; Imran, Muhammad; Ali, Jalil

2017-03-01

Laser-induced breakdown spectroscopy (LIBS) is a direct and versatile analytical technique that performs the elemental composition analysis based on optical emission produced by laser induced-plasma, with a little or no sample preparation. The performance of the LIBS technique relies on the choice of experimental conditions which must be thoroughly explored and optimized for each application. The main parameters affecting the LIBS performance are the laser energy, laser wavelength, pulse duration, gate delay, geometrical set-up of the focusing and collecting optics. In LIBS quantitative analysis, the gate delay and laser energy are very important parameters that have pronounced impact on the accuracy of the elemental composition information of the materials. The determination of calcium elements in the pelletized samples was investigated and served for the purpose of optimizing the gate delay and laser energy by studying and analyzing the results from emission intensities collected and signal to background ratio (S/B) for the specified wavelengths.

Proof-of-concept experiment for on-line laser induced breakdown spectroscopy analysis of impurity layer deposited on optical window and other plasma facing components of Aditya tokamak

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

Maurya, Gulab Singh; Kumar, Rohit; Rai, Awadhesh Kumar, E-mail: awadheshkrai@rediffmail.com

2015-12-15

In the present manuscript, we demonstrate the design of an experimental setup for on-line laser induced breakdown spectroscopy (LIBS) analysis of impurity layers deposited on specimens of interest for fusion technology, namely, plasma-facing components (PFCs) of a tokamak. For investigation of impurities deposited on PFCs, LIBS spectra of a tokamak wall material like a stainless steel sample (SS304) have been recorded through contaminated and cleaned optical windows. To address the problem of identification of dust and gases present inside the tokamak, we have shown the capability of the apparatus to record LIBS spectra of gases. A new approach known asmore » “back collection method” to record LIBS spectra of impurities deposited on the inner surface of optical window is presented.« less

Analysis of major elements in pigmented melanocytic chicken skin using laser-induced breakdown spectroscopy.

PubMed

Lee, Jong Jin; Moon, Youngmin; Han, Jung Hyun; Jeong, Sungho

2017-04-01

The concentration difference of major elements in melanocytic skin with respect to pigmentation level is analysed by laser-induced breakdown spectroscopy (LIBS) to investigate the applicability of LIBS as an in situ feedback tool for selective and complete laser removal of melanocytic skin tissue like nevus. The skin of black silkie chicken which had a characteristic darkly pigmented perifollicular skin surrounded by lightly pigmented extrafollicular skin was used as the sample. The results showed higher LIBS signal intensities of Ca 2+ and Mg 2+ but lower intensities of Na + , Cl - and K + in the perifollicular skin than in the extrafollicular skin, which demonstrated the feasibility to use LIBS as a reliable method to distinguish skin tissues with difference in pigmentation level. Plasma emission of biochemical elements generated with a laser irradiation on melanocytic skin lesion. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Combination of honokiol and magnolol inhibits hepatic steatosis through AMPK-SREBP-1 c pathway.

PubMed

Lee, Ju-Hee; Jung, Ji Yun; Jang, Eun Jeong; Jegal, Kyung Hwan; Moon, Soo Young; Ku, Sae Kwang; Kang, Seung Ho; Cho, Il Je; Park, Sook Jahr; Lee, Jong Rok; Zhao, Rong Jie; Kim, Sang Chan; Kim, Young Woo

2015-04-01

Honokiol and magnolol, as pharmacological biphenolic compounds of Magnolia officinalis, have been reported to have antioxidant and anti-inflammatory properties. Sterol regulatory element binding protein-1 c (SREBP-1 c) plays an important role in the development and processing of steatosis in the liver. In the present study, we investigated the effects of a combination of honokiol and magnolol on SREBP-1 c-dependent lipogenesis in hepatocytes as well as in mice with fatty liver due to consumption of high-fat diet (HFD). Liver X receptor α (LXRα) agonists induced activation of SREBP-1 c and expression of lipogenic genes, which were blocked by co-treatment of honokiol and magnolol (HM). Moreover, a combination of HM potently increased mRNA of fatty acid oxidation genes. HM induced AMP-activated protein kinase (AMPK), an inhibitory kinase of the LXRα-SREBP-1 c pathway. The role of AMPK activation induced by HM was confirmed using an inhibitor of AMPK, Compound C, which reversed the ability of HM to both inhibit SREBP-1 c induction as well as induce genes for fatty acid oxidation. In mice, HM administration for four weeks ameliorated HFD-induced hepatic steatosis and liver dysfunction, as indicated by plasma parameters and Oil Red O staining. Taken together, our results demonstrated that a combination of HM has beneficial effects on inhibition of fatty liver and SREBP-1 c-mediated hepatic lipogenesis, and these events may be mediated by AMPK activation. © 2014 by the Society for Experimental Biology and Medicine.

Combination of honokiol and magnolol inhibits hepatic steatosis through AMPK-SREBP-1 c pathway

PubMed Central

Lee, Ju-Hee; Jung, Ji Yun; Jang, Eun Jeong; Jegal, Kyung Hwan; Moon, Soo Young; Ku, Sae Kwang; Kang, Seung Ho; Cho, Il Je; Park, Sook Jahr; Lee, Jong Rok; Zhao, Rong Jie; Kim, Sang Chan

2015-01-01

Honokiol and magnolol, as pharmacological biphenolic compounds of Magnolia officinalis, have been reported to have antioxidant and anti-inflammatory properties. Sterol regulatory element binding protein-1 c (SREBP-1 c) plays an important role in the development and processing of steatosis in the liver. In the present study, we investigated the effects of a combination of honokiol and magnolol on SREBP-1 c-dependent lipogenesis in hepatocytes as well as in mice with fatty liver due to consumption of high-fat diet (HFD). Liver X receptor α (LXRα) agonists induced activation of SREBP-1 c and expression of lipogenic genes, which were blocked by co-treatment of honokiol and magnolol (HM). Moreover, a combination of HM potently increased mRNA of fatty acid oxidation genes. HM induced AMP-activated protein kinase (AMPK), an inhibitory kinase of the LXRα-SREBP-1 c pathway. The role of AMPK activation induced by HM was confirmed using an inhibitor of AMPK, Compound C, which reversed the ability of HM to both inhibit SREBP-1 c induction as well as induce genes for fatty acid oxidation. In mice, HM administration for four weeks ameliorated HFD-induced hepatic steatosis and liver dysfunction, as indicated by plasma parameters and Oil Red O staining. Taken together, our results demonstrated that a combination of HM has beneficial effects on inhibition of fatty liver and SREBP-1 c-mediated hepatic lipogenesis, and these events may be mediated by AMPK activation. PMID:25125496

DNA binding of the p21 repressor ZBTB2 is inhibited by cytosine hydroxymethylation

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

Lafaye, Céline; Barbier, Ewa; Miscioscia, Audrey

2014-03-28

Highlights: • 5-hmC epigenetic modification is measurable in HeLa, SH-SY5Y and UT7-MPL cell lines. • ZBTB2 binds to DNA probes containing 5-mC but not to sequences containing 5-hmC. • This differential binding is verified with DNA sequences involved in p21 regulation. - Abstract: Recent studies have demonstrated that the modified base 5-hydroxymethylcytosine (5-hmC) is detectable at various rates in DNA extracted from human tissues. This oxidative product of 5-methylcytosine (5-mC) constitutes a new and important actor of epigenetic mechanisms. We designed a DNA pull down assay to trap and identify nuclear proteins bound to 5-hmC and/or 5-mC. We applied thismore » strategy to three cancerous cell lines (HeLa, SH-SY5Y and UT7-MPL) in which we also measured 5-mC and 5-hmC levels by HPLC-MS/MS. We found that the putative oncoprotein Zinc finger and BTB domain-containing protein 2 (ZBTB2) is associated with methylated DNA sequences and that this interaction is inhibited by the presence of 5-hmC replacing 5-mC. As published data mention ZBTB2 recognition of p21 regulating sequences, we verified that this sequence specific binding was also alleviated by 5-hmC. ZBTB2 being considered as a multifunctional cell proliferation activator, notably through p21 repression, this work points out new epigenetic processes potentially involved in carcinogenesis.« less

Evaluation of Brāhmī ghṛtam in children suffering from Attention Deficit Hyperactivity Disorder

PubMed Central

Bhalerao, Supriya; Munshi, Renuka; Nesari, Tanuja; Shah, Heenal

2013-01-01

Introduction: Attention Deficit Hyperactivity Disorder (ADHD) is characterized by a persistent pattern of inattention and/or hyperactivity-impulsivity. In view of the adverse effects associated with psycho-stimulants used for the treatment of this disorder, efficacy of Brāhmī ghṛtam was evaluated in this condition. Materials and Methods: After following due ethical considerations, children of either sex between the age group of 6 and 12 years diagnosed to be suffering from mixed variety of ADHD as per The Diagnostic and Statistical Manual of Mental Disorders (DSM) IV criteria irrespective of other co-morbid psychiatric illnesses were recruited in the study. Initially a pilot study (n = 10) was carried out to confirm the efficacy of the identified dose of Brāhmī ghṛtam. Using this dose, further therapeutic confirmatory study (n = 27) was carried out, wherein Brāhmī ghṛtam was compared with methylphenidate. Effect on ADHD symptoms was assessed using the Dupaul ADHD rating scale and this was the main efficacy parameter. Results: In the pilot exploratory study, Brāhmī ghṛtam showed 66% decrease in total ADHD score. In the therapeutic confirmatory study, only 16% improvement was seen with Brāhmī ghṛtam, which was similar to methylphenidate, standard treatment for ADHD that was used as a comparator in the present study. No side-effects were reported in both studies. Conclusion: Our study thus has adequately demonstrated efficacy and safety of Brāhmī ghṛtam in ADHD. PMID:25284947

Cost–consequence analysis of daily continuous remote monitoring of implantable cardiac defibrillator and resynchronization devices in the UK

PubMed Central

Burri, Haran; Sticherling, Christian; Wright, David; Makino, Koji; Smala, Antje; Tilden, Dominic

2013-01-01

Aims The need for ongoing and lifelong follow-up (FU) of patients with cardiac implantable electric devices (CIED) requires significant resources. Remote CIED management has been established as a safe alternative to conventional periodical in-office FU (CFU). An economic model compares the long-term cost and consequences of using daily Home Monitoring® (HM) instead of CFU. Methods and results A cost–consequence evaluation comparing HM vs. CFU was performed using a Markov cohort model and data relating to events and costs identified via a systematic review of the literature. The model is conservative, without assuming a reduction of cardiovascular events by HM such as decompensated heart failure or mortality, or considering cost savings such as for transportation. Also cost savings due to an improved timing of elective device replacement, and fewer FU visits needed in patients near device replacement are not considered. Over 10 years, HM is predicted to be cost neutral at about GBP 11 500 per patient in either treatment arm, with all costs for the initial investment into HM and fees for ongoing remote monitoring included. Fewer inappropriate shocks (−51%) reduce the need for replacing devices for battery exhaustion (−7%); the number of FU visits is predicted to be halved by HM. Conclusion From a UK National Health Service perspective, HM is cost neutral over 10 years. This is mainly accomplished by reducing the number of battery charges and inappropriate shocks, resulting in fewer device replacements, and by reducing the number of in-clinic FU visits. PMID:23599169

Cost-consequence analysis of daily continuous remote monitoring of implantable cardiac defibrillator and resynchronization devices in the UK.

PubMed

Burri, Haran; Sticherling, Christian; Wright, David; Makino, Koji; Smala, Antje; Tilden, Dominic

2013-11-01

The need for ongoing and lifelong follow-up (FU) of patients with cardiac implantable electric devices (CIED) requires significant resources. Remote CIED management has been established as a safe alternative to conventional periodical in-office FU (CFU). An economic model compares the long-term cost and consequences of using daily Home Monitoring® (HM) instead of CFU. A cost-consequence evaluation comparing HM vs. CFU was performed using a Markov cohort model and data relating to events and costs identified via a systematic review of the literature. The model is conservative, without assuming a reduction of cardiovascular events by HM such as decompensated heart failure or mortality, or considering cost savings such as for transportation. Also cost savings due to an improved timing of elective device replacement, and fewer FU visits needed in patients near device replacement are not considered. Over 10 years, HM is predicted to be cost neutral at about GBP 11 500 per patient in either treatment arm, with all costs for the initial investment into HM and fees for ongoing remote monitoring included. Fewer inappropriate shocks (-51%) reduce the need for replacing devices for battery exhaustion (-7%); the number of FU visits is predicted to be halved by HM. From a UK National Health Service perspective, HM is cost neutral over 10 years. This is mainly accomplished by reducing the number of battery charges and inappropriate shocks, resulting in fewer device replacements, and by reducing the number of in-clinic FU visits.

Twin hydroxymethyluracil-A base pair steps define the binding site for the DNA-binding protein TF1.

PubMed

Grove, A; Figueiredo, M L; Galeone, A; Mayol, L; Geiduschek, E P

1997-05-16

The DNA-bending protein TF1 is the Bacillus subtilis bacteriophage SPO1-encoded homolog of the bacterial HU proteins and the Escherichia coli integration host factor. We recently proposed that TF1, which binds with high affinity (Kd was approximately 3 nM) to preferred sites within the hydroxymethyluracil (hmU)-containing phage genome, identifies its binding sites based on sequence-dependent DNA flexibility. Here, we show that two hmU-A base pair steps coinciding with two previously proposed sites of DNA distortion are critical for complex formation. The affinity of TF1 is reduced 10-fold when both of these hmU-A base pair steps are replaced with A-hmU, G-C, or C-G steps; only modest changes in affinity result when substitutions are made at other base pairs of the TF1 binding site. Replacement of all hmU residues with thymine decreases the affinity of TF1 greatly; remarkably, the high affinity is restored when the two hmU-A base pair steps corresponding to previously suggested sites of distortion are reintroduced into otherwise T-containing DNA. T-DNA constructs with 3-base bulges spaced apart by 9 base pairs of duplex also generate nM affinity of TF1. We suggest that twin hmU-A base pair steps located at the proposed sites of distortion are key to target site selection by TF1 and that recognition is based largely, if not entirely, on sequence-dependent DNA flexibility.

Individualized Hydrocodone Therapy Based on Phenotype, Pharmacogenetics, and Pharmacokinetic Dosing.

PubMed

Linares, Oscar A; Fudin, Jeffrey; Daly, Annemarie L; Boston, Raymond C

2015-12-01

(1) To quantify hydrocodone (HC) and hydromorphone (HM) metabolite pharmacokinetics with pharmacogenetics in CYP2D6 ultra-rapid metabolizer (UM), extensive metabolizer (EM), and poor metabolizer (PM) metabolizer phenotypes. (2) To develop an HC phenotype-specific dosing strategy for HC that accounts for HM production using clinical pharmacokinetics integrated with pharmacogenetics for patient safety. In silico clinical trial simulation. Healthy white men and women without comorbidities or history of opioid, or any other drug or nutraceutical use, age 26.3±5.7 years (mean±SD; range, 19 to 36 y) and weight 71.9±16.8 kg (range, 50 to 108 kg). CYP2D6 phenotype-specific HC clinical pharmacokinetic parameter estimates and phenotype-specific percentages of HM formed from HC. PMs had lower indices of HC disposition compared with UMs and EMs. Clearance was reduced by nearly 60% and the t1/2 was increased by about 68% compared with EMs. The canonical order for HC clearance was UM>EM>PM. HC elimination mainly by the liver, represented by ke, was reduced about 70% in PM. However, HC's apparent Vd was not significantly different among UMs, EMs, and PM. The canonical order of predicted plasma HM concentrations was UM>EM>PM. For each of the CYP2D6 phenotypes, the mean predicted HM levels were within HM's therapeutic range, which indicates HC has significant phenotype-dependent pro-drug effects. Our results demonstrate that pharmacogenetics afford clinicians an opportunity to individualize HC dosing, while adding enhanced opportunity to account for its conversion to HM in the body.

Epigenetic Reprogramming Strategies to Reverse Global Loss of 5-Hydroxymethylcytosine, a Prognostic Factor for Poor Survival in High-grade Serous Ovarian Cancer

PubMed Central

Tucker, Douglass W.; Getchell, Christopher R.; McCarthy, Eric T.; Ohman, Anders W.; Sasamoto, Naoko; Xu, Shuyun; Ko, Joo Yeon; Gupta, Mamta; Shafrir, Amy; Medina, Jamie E.; Lee, Jonathan J.; MacDonald, Lauren A.; Malik, Ammara; Hasselblatt, Kathleen T; Li, Wenjing; Zhang, Hong; Kaplan, Samuel J.; Murphy, George F.; Hirsch, Michelle S.; Liu, Joyce F.; Matulonis, Ursula A.; Terry, Kathryn L.; Lian, Christine G.; Dinulescu, Daniela M.

2018-01-01

Purpose A major challenge in platinum-based cancer therapy is the clinical management of chemoresistant tumors, which have a largely unknown pathogenesis at the level of epigenetic regulation. Experimental Design We evaluated the potential of using global loss of 5-hydroxymethylcytosine (5-hmC) levels as a novel diagnostic and prognostic epigenetic marker to better assess platinum-based chemotherapy response and clinical outcome in high-grade serous tumors (HGSOC), the most common and deadliest subtype of ovarian cancer. Furthermore, we identified a targetable pathway to reverse these epigenetic changes, both genetically and pharmacologically. Results This study shows that decreased 5-hmC levels are an epigenetic hallmark for malignancy and tumor progression in HGSOC. In addition, global 5-hmC loss is associated with a decreased response to platinum-based chemotherapy, shorter time to relapse, and poor overall survival in patients newly diagnosed with HGSOC. Interestingly, the rescue of 5-hmC loss restores sensitivity to platinum chemotherapy in vitro and in vivo, decreases the percentage of tumor cells with cancer stem cell markers, and increases overall survival in an aggressive animal model of platinum-resistant disease. Conclusions Consequently, a global analysis of patient 5-hmC levels should be included in future clinical trials, which use pretreatment with epigenetic adjuvants to elevate 5-hmC levels and improve the efficacy of current chemotherapies. Identifying prognostic epigenetic markers and altering chemotherapeutic regimens to incorporate DNMTi pretreatment in tumors with low 5-hmC levels could have important clinical implications for newly diagnosed HGSOC disease. PMID:29263182

Human Milk Cells and Lipids Conserve Numerous Known and Novel miRNAs, Some of Which Are Differentially Expressed during Lactation

PubMed Central

Alsaweed, Mohammed; Lai, Ching Tat; Hartmann, Peter E.; Geddes, Donna T.; Kakulas, Foteini

2016-01-01

Human milk (HM) is rich in miRNAs, which are thought to contribute to infant protection and development. We used deep sequencing to profile miRNAs in the cell and lipid fractions of HM obtained post-feeding from 10 lactating women in months 2, 4, and 6 postpartum. In both HM fractions, 1,195 mature known miRNAs were identified, which were positively associated with the cell (p = 0.048) and lipid (p = 0.010) content of HM. An additional 5,167 novel miRNA species were predicted, of which 235 were high-confidence miRNAs. HM cells contained more known miRNAs than HM lipids (1,136 and 835 respectively, p<0.001). Although the profile of the novel miRNAs was very different between cells and lipids, with the majority conserved in the cell fraction and being mother-specific, 2/3 of the known miRNAs common between cells and lipids were similarly expressed (p>0.05). Great similarities between the two HM fractions were also found in the profile of the top 20 known miRNAs. These were largely similar also between the three lactation stages examined, as were the total miRNA concentration, and the number and expression of the known miRNAs common between cells and lipids (p>0.05). Yet, approximately a third of all known miRNAs were differentially expressed during the first 6 months of lactation (p<0.05), with more pronounced miRNA upregulation seen in month 4. These findings indicate that although the total miRNA concentration of HM cells and lipids provided to the infant does not change in first 6 months of lactation, the miRNA composition is altered, particularly in month 4 compared to months 2 and 6. This may reflect the remodeling of the gland in response to infant feeding patterns, which usually change after exclusive breastfeeding, suggesting adaptation to the infant’s needs. PMID:27074017

Fluorescence, electrophoretic and chromatographic fingerprints of herbal medicines and their comparative chemometric analysis.

PubMed

Mazina, Jekaterina; Vaher, Merike; Kuhtinskaja, Maria; Poryvkina, Larisa; Kaljurand, Mihkel

2015-07-01

The aim of the present study was to compare the polyphenolic compositions of 47 medicinal herbs (HM) and four herbal tea mixtures from Central Estonia by rapid, reliable and sensitive Spectral Fluorescence Signature (SFS) method in a front face mode. The SFS method was validated for the main identified HM representatives including detection limits (0.037mgL(-1) for catechin, 0.052mgL(-1) for protocatechuic acid, 0.136mgL(-1) for chlorogenic acid, 0.058mgL(-1) for syringic acid and 0.256mgL(-1) for ferulic acid), linearity (up to 5.0-15mgL(-1)), intra-day precision (RSDs=6.6-10.6%), inter-day precision (RSDs=6.4-13.8%), matrix effect (-15.8 to +5.5) and recovery (85-107%). The phytochemical fingerprints were differentiated by parallel factor analysis (PARAFAC) combined with hierarchical cluster analysis (CA) and principal component analysis (PCA). HM were clustered into four main clusters (catechin-like, hydroxycinnamic acid-like, dihydrobenzoic acid-like derivatives containing HM and HM with low/very low content of fluorescent constituents) and 14 subclusters (rich, medium, low/very low contents). The average accuracy and precision of CA for validation HM set were 97.4% (within 85.2-100%) and 89.6%, (within 66.7-100%), respectively. PARAFAC-PCA/CA has improved the analysis of HM by the SFS method. The results were verified by two separation methods CE-DAD and HPLC-DAD-MS also combined with PARAFAC-PCA/CA. The SFS-PARAFAC-PCA/CA method has potential as a rapid and reliable tool for investigating the fingerprints and predicting the composition of HM or evaluating the quality and authenticity of different standardised formulas. Moreover, SFS-PARAFAC-PCA/CA can be implemented as a laboratory and/or an onsite method. Copyright © 2015 Elsevier B.V. All rights reserved.

The Brazilian market of herbal medicinal products and the impacts of the new legislation on traditional medicines.

PubMed

Carvalho, Ana Cecília Bezerra; Lana, Túlio Nader; Perfeito, João Paulo Silvério; Silveira, Dâmaris

2018-02-15

the herbal medicinal products (HMP) market is expanding in the world, an expansion that has not occurred in Brazil when considering the number of licensed products. Despite being a megadiverse country, the number of HMP licensed in Brazil is small, and the number of HMP obtained from native species is even smaller. A new legislation for herbal products licensing, which divides the products into two categories, Herbal Medicine (HM) and Traditional Herbal Product (THP) was launched in Brazil focusing on traditional use, as well as a law regulating the use of biodiversity and traditional knowledge. to evaluate the situation of HMP licensed in Brazil and to make a comparison with the data obtained in 2008 and 2011, discussing the evolution of the licensed products and the possible impacts of the new legislation. a survey was carried out in the Brazilian Health Regulatory Agency (Anvisa) database to verify the HMP licensed in Brazil in September 2016. The data obtained were compared with two surveys previously published. There are 332 single, and 27 combined HM, totaling 359 HM licensed in Brazil. There is no THP notified in Anvisa's system yet. There are 214 HM classified as nonprescription (OTC), while 145 are sold under prescription, one of them with prescription retention. There are 101 plant species licensed as active in HM in Brazil, 39 of which are native, adapted or cultivated. The most licensed plant species is Mikania glomerata Spreng., with 25 HM licensed. The article includes tables with plant species that have derivatives licensed as simple and combined HM, their therapeutic classification, the native plant species indication and the distribution of the companies by Brazilian regions. There are few licensed HM in Brazil, and this number has been decreasing in recent years. It is expected that the data obtained, together with the changes promoted in sanitary and environmental rules, will help to develop and regulate HMP chain in Brazil. Copyright © 2017 Elsevier B.V. All rights reserved.

Cost of myopic patients with and without myopic choroidal neovascularisation.

PubMed

Ruiz-Moreno, J M; Roura, M

2016-06-01

To study the costs associated with high myopia (HM) with choroidal neovascularisation (mCNV) or without mCNV. Observational, retrospective, cross-sectional, and multicentre study (HM and mCNV) conducted on adult patients. Annualised medical direct cost (MDC) from the perspective of the National Health System, the non-medical direct cost (nMDC) from the patient perspective, and productivity losses were calculated. A total of 137 mCNV and 48 HM patients were included (mean age [SD]: 55.1 [2.8] vs. 54.7 [13.8]; P=.2), with 80% women in both groups. The observation time (months) ranged from 17.9 (9.6) right eye (RE) and 20.0 (9.7), left eye (LE) in mCNV and 47.1 (21.5) RE/45.5 (20.7) LE in MM. A higher percentage of emergency room visits was observed in mCNV vs. HM patients (41.7 vs. 25%; P=.06) and retinal specialists (91.2 vs. 77.1%; P=.01). The MDC was higher in mCNV: € 1,985 (95% CI: 1772-2198) vs. € 356 (251-480) HM, P<.001. The nMDC was also higher in mCNV: € 256 (11-524) vs. €19 (11-26) HM, P>.4. The number of affected eyes, the follow-up time, and the mCNV were factors associated with direct costs. The impact on work productivity was higher in mCNV (quite/very concerned): 27.7 vs. 10.4% HM. The mCNV showed a significant association with activity impairment (OR: 3.47, 95% CI: 10.101-1.195). mCNV involves higher medical costs than HM. In addition, mCNV patients have a greater need of care and assistive devices, and greater impact of the disease in their work productivity. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Colliding Winds in Symbiotic Binary Systems. I. Analytic and Numerical Solutions

NASA Astrophysics Data System (ADS)

Kenny, H. T.; Taylor, A. R.

2005-01-01

We present new formulations of binary colliding wind models appropriate to symbiotic star systems. The derived models differ from previous formulations in assuming mixing of the shocked material from both incoming streams, rather than postulating a self-sustaining contact discontinuity. The CWb model (colliding winds, binary) extends the work of Girard and Willson by the derivation of an adiabatic temperature, the consideration of radiative cooling, the inclusion of thermal pressures in the incoming winds, and the treatment of interaction shells of finite thickness and density. The finite thickness of the interaction shell allows for calculation of its radiative intensity distribution. The CWc model (colliding winds, concentric) is a similar extension of the model of Kwok, Purton, and Fitzgerald. It is derived in a manner parallel to that of the CWb model, thereby facilitating a unification of the two models. A unified model is desired since wind collisions in symbiotic systems should include aspects of both CWb and CWc interactions. Two examples of model applications are presented: a comparison of the flux densities arising from colliding winds (CWb model) with those arising from the ionization of the surrounding medium (STB model) in the galactic population of symbiotic stars, and model imaging of the symbiotic nova HM Sge.

[Response of yield, quality and nitrogen use efficiency to nitrogen fertilizer from mechanical transplanting super japonica rice].

PubMed

Wei, Hai-Yan; Wang, Ya-Jiang; Meng, Tian-Yao; Ge, Meng-Jie; Zhang, Hong-Cheng; Dai, Qi-Gen; Huo, Zhong-Yang; Xu, Ke

2014-02-01

Five super japonica rice cultivars were grown by mechanical transplanting in field and seven N treatments with total N application rate of 0, 150, 187.5, 225, 262.5, 300 and 337.5 kg x hm(-2) respectively were adopted to study the effects of N rate on rice yield, quality and N use efficiency. The differences between N requirement for obtaining the highest yield and for achieving the best economic benefit were compared. With the increase of N fertilizer rate, the yields of five super japonica rice cultivars increased firstly and then descended, achieving the highest yield at the N level of 300 kg x hm(-2) ranging from 10.33-10.60 kg x hm(-2). Yield increase mainly attributed to the large number of spikelet, for the total spikelet number of each rice cultivar reached the maximum value at the 300 kg x hm(-2) N level. With the increase of N application, the rates of brown rice, milled rice, head milled rice and the protein content of the five super japonica rice cultivars were all increased, and the rates of brown rice, milled rice, head milled rice and the protein con- tent were higher at 337.5 kg x hm(-2) N level than at 0 kg x hm(-2) N level by 3.3%-4.2%, 2.9%-6.0%, 4.4%-33.7% and 23.8%-44.3%, respectively. While the amylose content, gel consistency and taste value of the five rice cultivars were all decreased, and the amylose content, gel consistency and taste value were lower at 337.5 kg x hm(-2) N level than at 0 kg x hm(-2) N level by 12.4%-38.9%, 10.3%-28.5% and 20.3%-29.7%, respectively. The chalkiness increased firstly and then decreased while the change of chalky rate varied with the cultivars. With the increase of N application, the N use efficiency, agronomic N use efficiency and physiological N use efficiency decreased while the N uptake of grain increased significantly. If the cost of N fertilizer was taken into account, the N fertilizer amount to obtain the optimal economic benefits would be 275.68 kg x hm(-2) with the corresponding yield of 9.97 t x hm(-2). Therefore, in the existing super rice production, classified management of N fertilizer would be required to meet differentiated demands of high yield, good quality, high efficiency, low N fertilizer input and so on.

[Analysis of urban forest landscape pattern in Hefei].

PubMed

Wu, Zemin; Wu, Wenyou; Gao, Jian; Zhang, Shaojie

2003-12-01

Based on the theory and methodology of landscape ecology, the landscape pattern of the study area (17.6 km2) in the downtown of Hefei was analyzed by using the techniques of RS, GPS and GIS. The object was to provide a comprehensive method to study urban forest structure and its function in environmental improvement. The results showed that there were 5 major landscape elements, i.e., building and hard pavement surface, water, road, urban forest, and general green land in the area. The landscape matrix was building and pavement surface, occupied 73.13% of total land. Road was the typical corridor element in the city and occupied 6.89%. Green land occupied 11.44%, in which, urban forest patch occupied 9.18%. There were 408 urban forest patches, with an area of 161.16 hm2. The average area of the patch was 0.396 hm2, and the maximum area was 12 hm2. 48% of urban forest patch was identified as small scale patches with < 500 m2 of area, and only 8.6% of them was larger than 1 hm2. The number of general green land patch was 255, with an area of 39.74 hm2, which accounted for 2.26% of land area, and its average and maximum area was 0.1558 hm2 and 3.86 hm2, respectively. There were 147 water patches, with an area of 149.93 hm2, and occupied 8.54% of land, and the average and maximum area of the patch was 1.02 hm2 and 16 hm2, respectively. In the study area, both of the Shannon-Weiner landscape diversity index and evenness were low, only 0.928 and 0.576, respectively. In addition, the dominance of urban forest patch and general green land was 0.39 showing that the two landscape elements had a certain influence on the environment of the study area. The concept of interior habitat for forest was introduced in this paper, which was employed to make a scale class system of urban forest patch. The threshold area with interior habitat for urban forest patch was 9800 m2, and there was 31.69 hm2 of interior habitat of urban forest in total, which occupied 19.7% of the total area of urban forest patch. This situation was not favorable for providing more habitats to support species diversity. It's suggested that the concept of interior habitat could be employed to identify urban forest patch, and a scale system of small scale patch of urban forest-middle patch-large patch-extra large patch was build in the paper. Based on this system, the ratio of different scales of urban forest patch in the study area should be 2:2:2:3. The authors also suggested that larger pieces (1.5-3.0 hm2) of urban forest patch should be built, and more urban forests should be established in the northeastern part of the city in the future.

Influence of Atmospheric Pressure and Composition on LIBS

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

Hatch, Jeremy J.; Scott, Jill R.; Effenberger, A. J. Jr.

2014-03-01

Most LIBS experiments are conducted at standard atmospheric pressure in air. However, there are LIBS studies that vary the pressure and composition of the gas. These studies have provided insights into fundamentals of the mechanisms that lead to the emission and methods for improving the quality of LIBS spectra. These atmospheric studies are difficult because the effects of pressure and gas composition and interconnected, making interpretation of the results difficult. The influence of pressures below and above 760 Torr have been explored. Performing LIBS on a surface at reduced pressures (<760 Torr) can result in enhanced spectra due to highermore » resolution, increased intensity, improved signal-to-noise (S/N), and increased ablation. Lower pressures produce increased resolution because the line width in LIBS spectra is predominantly due to Stark and Doppler broadening. Stark broadening is primarily caused from collisions between electrons and atoms, while Doppler broadening is proportional to the plasma temperature. Close examination using a high resolution spectrometer reveals that spectra show significant peak broadening and self-absorption as pressures increase, especially for pressures >760 Torr. During LIBS plasma expansion, energy is lost to the surrounding atmosphere, which reduces the lifetime of the laser plasma. Therefore, reducing the pressure increases the lifetime of the plasma, allowing more light from the laser plasma to be collected; thus, increasing the observed signal intensity. However, if pressures are too low (<10 Torr), then there is a steep drop in LIBS spectral intensity. This loss in intensity is mostly due to a disordered plasma that results from the lack of sufficient atmosphere to provide adequate confinement. At reduced pressures, the plasma expands into a less dense atmosphere, which results in a less dense shock wave. The reduced density in the shock wave results in reduced plasma shielding, allowing more photons to reach the sample. Increasing the number of photons interacting with the sample surface results in increased ablation, which can lead to increased intensity. The composition of the background gas has been shown to greatly influence the observed LIBS spectra by altering the plasma temperature, electron density, mass removal, and plasma shielding that impact the emission intensity and peak resolution. It has been reported that atmospheric Ar results in the highest plasma temperature and electron density, while a He atmosphere results in the lowest plasma temperatures and electron density. Studying temporal data, it was also found that Ar had the slowest decay of both electron density and plasma temperature, while He had the fastest decay in both parameters. The higher plasma temperature and electron density results in an increase in line broadenin, or poor resolution, for Ar compared to He. A rapidly developing LIBS plasma with a sufficient amount of electrons can absorb a significant portion of the laser pulse through inverse Bremsstahlung. Ar (15.8 eV ) is more easily ionized than He (24.4 eV). The breakdown threshold for He at 760 Torr is approximately 3 times greater than Ar and approximately 5 times greater at 100 Torr. The lower breakdown threshold in Ar, compared to He, creates an environment favorable for plasma shielding, which reduces sample vaporization and leads to a weaker LIBS signal.« less

Enhanced Laser-Induced Breakdown Spectroscopy By Second-Pulse Selective Wavelength Excitation

NASA Astrophysics Data System (ADS)

Vidal, F.; Chaker, M.; Goueguel, C.; Laville, S.; Loudyi, H.; Rifai, K.; Sabsabi, M.

2008-09-01

We investigate the use of a second laser with a selected wavelength to improve the limit of detection (LoD) of trace elements in the Laser-Induced Breakdown Spectroscopy (LIBS) technique. We consider the combination of LIBS with Laser-Induced Fluorescence (LIF), in which the second laser is used to excite trace elements in the plasma. The influence of the main experimental parameters on the trace elements LIF signal, namely the ablation fluence, the excitation energy, and the inter-pulse delay, was studied experimentally and a physical interpretation of the results was presented. For illustrative purpose we considered detection of Pb in brass samples and in water. The plasma was produced by a Q-switched Nd:YAG laser and then re-excited by a nanosecond optical parametric oscillator laser. We found out that the optimal conditions for our experimental set-up were obtained for relatively weak ablation fluence of 2-3 J/cm2 and inter-pulse delay of 5-10 μs. Using the LIBS-LIFS technique, a single-shot LoD for detection of lead of about 1.5 part per million (ppm) was obtained for solids and 0.5 ppm for liquids. These LoDs represent an improvement of about two orders of magnitude with respect to LIBS. We also discuss resonance-enhanced LIBS (RELIBS), in which the second laser excites the main plasma component instead of the impurities. For the set of parameters used the RELIBS, Pb signal does not differ significantly from the LIBS signal except at low ablation fluence.

The state of understanding of the lithium-ion-battery graphite solid electrolyte interphase (SEI) and its relationship to formation cycling

DOE PAGES

An, Seong Jin; Li, Jianlin; Daniel, Claus; ...

2016-04-09

An in-depth review is presented on the science of lithium-ion battery (LIB) solid electrolyte interphase (SEI) formation on the graphite anode, including structure, morphology, chemical composition, electrochemistry, formation mechanism, and LIB formation cycling. During initial operation of LIBs, the SEI layer forms on the graphite surfaces, the most commonly used anode material, due to side reactions with the electrolyte solvent/salt at low electro-reduction potentials. It is accepted that the SEI layer is essential to the long-term performance of LIBs, and it also has an impact on its initial capacity loss, self-discharge characteristics, cycle life, rate capability, and safety. While themore » presence of the anode SEI layer is vital, it is difficult to control its formation and growth, as the chemical composition, morphology, and stability depend on several factors. These factors include the type of graphite, electrolyte composition, electrochemical conditions, and cell temperature. Thus, SEI layer formation and electrochemical stability over long-term operation should be a primary topic of future investigation in the development of LIB technology. We review the progression of knowledge gained about the anode SEI, from its discovery in 1979 to the current state of understanding, and covers its formation process, differences in the chemical and structural makeup when cell materials and components are varied, methods of characterization, and associated reactions with the liquid electrolyte phase. It also discusses the relationship of the SEI layer to the LIB formation step, which involves both electrolyte wetting and subsequent slow charge-discharge cycles to grow the SEI.« less

LIBS analysis of hydroxyapatite extracted from bovine bone for Ca/P ratio measurements

NASA Astrophysics Data System (ADS)

Tariq, Usman; Haider, Zuhaib; Hussain, Rafaqat; Tufail, Kashif; Ali, Jalil

2017-03-01

Hydroxyapatite has been extensively used as a potential biocompatible ceramic in many orhtopedic applications. Hydroxyapatite is one of the members of calcium phosphate family and been used extensively as a bone substitute. The mechanical properties of hydroxyapatite itself, ceramics and bone cements prepared from hydroxyapatite vary greatly with slight variation in its Ca/P ratio. At present EDX, XRD, XRF and ICP-OES are being used for the determination of Ca/P ratio in hydroxyapatite. These techniques require special sample preparation, may also use toxic chemicals and usually are not very fast in giving the measurements. We report LIBS as a rapid alternative technique for calculation of Ca/P ratio in hydroxyapatite extracted from bovine bone (BHA). Ca/P ratio in laboratory prepared HA is calculated using LIBS and the results are validated against EDX results Ca/P ratio of the hydroxyapatite was calculated as 1.54±0.19 using LIBS while 1.63±0.03 using EDX. Ca/P ratio calculated by LIBS and EDX and showed comparable results with a difference of 5.5%. Moreover, plasma temperature and the ratio of the calcium (ion) line to calcium (atomic) line did not show significant variation in plasma conditions during measurements. The present study has demonstrated that LIBS can also be used for the determination of Ca/P ratio of hydroxyapatite and other calcium phosphates. At the request of all authors of the paper, and with the agreement of the Proceedings Editor, an updated version of this article was published on 24 May 2017.

Calibration-free quantitative analysis of elemental ratios in intermetallic nanoalloys and nanocomposites using Laser Induced Breakdown Spectroscopy (LIBS).

PubMed

Davari, Seyyed Ali; Hu, Sheng; Mukherjee, Dibyendu

2017-03-01

Intermetallic nanoalloys (NAs) and nanocomposites (NCs) have increasingly gained prominence as efficient catalytic materials in electrochemical energy conversion and storage systems. But their morphology and chemical compositions play critical role in tuning their catalytic activities, and precious metal contents. While advanced microscopy techniques facilitate morphological characterizations, traditional chemical characterizations are either qualitative or extremely involved. In this study, we apply Laser Induced Breakdown Spectroscopy (LIBS) for quantitative compositional analysis of NAs and NCs synthesized with varied elemental ratios by our in-house built pulsed laser ablation technique. Specifically, elemental ratios of binary PtNi, PdCo (NAs) and PtCo (NCs) of different compositions are determined from LIBS measurements employing an internal calibration scheme using the bulk matrix species as internal standards. Morphology and qualitative elemental compositions of the aforesaid NAs and NCs are confirmed from Transmission Electron Microscopy (TEM) images and Energy Dispersive X-ray Spectroscopy (EDX) measurements. LIBS experiments are carried out in ambient conditions with the NA and NC samples drop cast on silicon wafers after centrifugation to increase their concentrations. The technique does not call for cumbersome sample preparations including acid digestions and external calibration standards commonly required in Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) techniques. Yet the quantitative LIBS results are in good agreement with the results from ICP-OES measurements. Our results indicate the feasibility of using LIBS in future for rapid and in-situ quantitative chemical characterizations of wide classes of synthesized NAs and NCs. Copyright © 2016 Elsevier B.V. All rights reserved.

Can overeating induce conditioned taste avoidance in previously food restricted rats?

PubMed

Hertel, Amanda; Eikelboom, Roelof

2010-03-30

While feeding is rewarding, the feeling of satiation has been theorized to have a mixed affect. Using a food restriction model of overeating we examined whether bingeing was capable of supporting conditioned taste avoidance (CTA). Adult male Sprague-Dawley rats were maintained on either an ad lib (n=8) or restricted (50% of regular consumption; n=24) food access for 20 days. On Days 9, 14, and 19 all rats were given access to a novel saccharin solution in place of water, and two groups of food restricted rats were given access to either 100% of regular food consumption or ad lib food. Ad lib access in the restricted rats induced significant overeating on all three exposures. After all rats were returned to ad lib feeding, a 24h two-bottle saccharin/water choice test displayed significantly reduced saccharin consumption in the overeating rats, compared to those in the other 3 groups. To determine whether this avoidance was due to a learned association, a second experiment used a latent inhibition paradigm, familiarizing half the rats with the saccharin for 8 days prior to pairing it with overeating. Using the design of Experiment 1, with only the continuously ad lib and the restricted to ad lib feeding groups, it was found that the overeating-induced saccharin avoidance was attenuated by the pre-exposure. These results suggest that self-induced overeating is capable of supporting a learned avoidance of a novel solution suggestive of a conditioned satiety or taste avoidance. (c) 2009 Elsevier Inc. All rights reserved.

Elemental composition of Arctic soils and aerosols in Ny-Ålesund measured using laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Kim, Gibaek; Yoon, Young-Jun; Kim, Hyun-A.; Cho, Hee-joo; Park, Kihong

2017-08-01

Two laser-induced breakdown spectroscopy (LIBS) systems (soil LIBS and aerosol LIBS) were used to determine the elemental composition of soils and ambient aerosols less than 2.5 μm in Ny-Ålesund, Svalbard (the world's most northerly human settlement). For soil LIBS measurements, matrix effects such as moisture content, soil grain size, and surrounding gas on the LIBS response were minimized. When Ar gas was supplied onto the soil sample surfaces, a significant enhancement in LIBS emission lines was observed. Arctic soil samples were collected at 10 locations, and various elements (Al, Ba, C, Ca, Cu, Fe, H, K, Mg, Mn, N, Na, O, Pb, and Si) were detected in soils. The elemental distribution in arctic soils was clearly distinguishable from those in urban and abandoned mining soils in Korea. Moreover, the concentrations of most of anthropogenic metals were fairly low, and localized sources in extremely close proximity affected the elevated level of Cu in the soil samples derived from Ny-Ålesund. The number of elements detected in aerosols (C, Ca, H, K, Mg, Na, and O) was lower than those determined in soils. The elements in aerosols can mainly originate from minerals and sea salts. The elemental distribution in aerosols was also clearly distinguishable from that in soils, suggesting that the resuspension of local soil particles by wind erosion into aerosols was minimal. The daily variation of particle number concentration (RSD = 71%) and the elements in aerosols (RSD = 25%) varied substantially, possibly due to fluctuating air masses and meteorological conditions.

Elemental misinterpretation in automated analysis of LIBS spectra.

PubMed

Hübert, Waldemar; Ankerhold, Georg

2011-07-01

In this work, the Stark effect is shown to be mainly responsible for wrong elemental allocation by automated laser-induced breakdown spectroscopy (LIBS) software solutions. Due to broadening and shift of an elemental emission line affected by the Stark effect, its measured spectral position might interfere with the line position of several other elements. The micro-plasma is generated by focusing a frequency-doubled 200 mJ pulsed Nd/YAG laser on an aluminum target and furthermore on a brass sample in air at atmospheric pressure. After laser pulse excitation, we have measured the temporal evolution of the Al(II) ion line at 281.6 nm (4s(1)S-3p(1)P) during the decay of the laser-induced plasma. Depending on laser pulse power, the center of the measured line is red-shifted by 130 pm (490 GHz) with respect to the exact line position. In this case, the well-known spectral line positions of two moderate and strong lines of other elements coincide with the actual shifted position of the Al(II) line. Consequently, a time-resolving software analysis can lead to an elemental misinterpretation. To avoid a wrong interpretation of LIBS spectra in automated analysis software for a given LIBS system, we recommend using larger gate delays incorporating Stark broadening parameters and using a range of tolerance, which is non-symmetric around the measured line center. These suggestions may help to improve time-resolving LIBS software promising a smaller probability of wrong elemental identification and making LIBS more attractive for industrial applications.

[Effect of Characteristic Variable Extraction on Accuracy of Cu in Navel Orange Peel by LIBS].

PubMed

Li, Wen-bing; Yao, Ming-yin; Huang, Lin; Chen, Tian-bing; Zheng, Jian-hong; Fan, Shi-quan; Liu Mu-hua HE, Mu-hua; Lin, Jin-long; Ouyang, Jing-yi

2015-07-01

Heavy metals pollution in foodstuffs is more and more serious. It is impossible to satisfy the modern agricultural development by conventional chemical analysis. Laser induced breakdown spectroscopy (LIBS) is an emerging technology with the characteristic of rapid and nondestructive detection. But LIBS' s repeatability, sensitivity and accuracy has much room to improve. In this work, heavy metal Cu in Gannan Navel Orange which is the Jiangxi specialty fruit will be predicted by LIBS. Firstly, the navel orange samples were contaminated in our lab. The spectra of samples were collected by irradiating the peel by optimized LIBS parameters. The laser energy was set as 20 mJ, delay time of Spectral Data Gathering was set as 1.2 micros, the integration time of Spectral data gathering was set as 2 ms. The real concentration in samples was obtained by AAS (atom absorption spectroscopy). The characteristic variables Cu I 324.7 and Cu I 327.4 were extracted. And the calibration model was constructed between LIBS spectra and real concentration about Cu. The results show that relative error of the predicted concentrations of three relational model were 7.01% or less, reached a minimum of 0.02%, 0.01% and 0.02% respectively. The average relative errors were 2.33%, 3.10% and 26.3%. Tests showed that different characteristic variables decided different accuracy. It is very important to choose suitable characteristic variable. At the same time, this work is helpful to explore the distribution of heavy metals between pulp and peel.

[Identification of Dendrobium varieties by Fourier transform infrared spectroscopy combined with spectral retrieval].

PubMed

Liu, Fei; Wang, Yuan-zhong; Deng, Xing-yan; Jin, Hang; Yang, Chun-yan

2014-06-01

The infrared spectral of stems of 165 trees of 23 Dendrobium varieties were obtained by means of Fourier transform infrared spectroscopy technique. The spectra show that the spectra of all the samples were similar, and the main components of stem of Dendrobium is cellulose. By the spectral professional software Omnic8.0, three spectral databases were constructed. Lib01 includes of the average spectral of the first four trees of every variety, while Lib02 and Lib03 are constructed from the first-derivative spectra and the second-derivative spectra of average spectra, separately. The correlation search, the square difference retrieval and the square differential difference retrieval of the spectra are performed with the spectral database Lib01 in the specified range of 1 800-500 cm(-1), and the yield correct rate of 92.7%, 74.5% and 92.7%, respectively. The square differential difference retrieval of the first-derivative spectra and the second-derivative spectra is carried out with Lib02 and Lib03 in the same specified range 1 800-500 cm(-1), and shows correct rate of 93.9% for the former and 90.3% for the later. The results show that the first-derivative spectral retrieval of square differential difference algorithm is more suitabe for discerning Dendrobium varieties, and FTIR combining with the spectral retrieval method can identify different varieties of Dendrobium, and the correlation retrieval, the square differential retrieval, the first-derivative spectra and second-derivative spectra retrieval in the specified spectral range are effective and simple way of distinguishing different varieties of Dendrobium.

Remote in-situ laser-induced breakdown spectroscopy using optical fibers

NASA Astrophysics Data System (ADS)

Marquardt, Brian James

The following dissertation describes the development of methods for performing remote Laser-Induced Breakdown Spectroscopy (LIBS) using optical fibers. Studies were performed to determine the optimal excitation and collection parameters for remote LIBS measurements of glasses, soils and paint. A number of fiber-optic LIBS probes were developed and used to characterize various samples by plasma emission spectroscopy. A novel method for launching high-power laser pulses into optical fibers without causing catastrophic failure is introduced. A systematic study of a number of commercially available optical fibers was performed to determine which optical fibers were best suited for delivering high-power laser pulses. The general design of an all fiber-optic LIBS probe is described and applied to the determination of Pb in soil. A fiber-optic probe was developed for the microanalysis of solid samples remotely by LIBS, Raman spectroscopy and Raman imaging. The design of the probe allows for real-time sample imaging in-situ using coherent imaging fibers. This allows for precise atomic emission and Raman measurements to be performed remotely on samples in hostile or inaccessible environments. A novel technique was developed for collecting spectral plasma images using an acousto-optic tunable filter (AOTF). The spatial and temporal characteristics of the plasma were studied as a function of delay time. From the plasma images the distribution of Pb emission could be determined and fiber-optic designs could be optimized for signal collection. The performance of a two fiber LIBS probe is demonstrated for the determination of the amount of lead in samples of dry paint. It is shown that dry paint samples can be analyzed for their Pb content in-situ using a fiber-optic LIBS probe with detection limits well below the levels currently regulated by the Consumer Products Safety Commission. It is also shown that these measurements can be performed on both latex and enamel paints, and that Pb containing paint can be detected even under layers of non-lead containing paint. Experiments were performed to determine the optimal measurement parameters for performing LIBS studies of Department of Energy "waste" glasses. Calibration data for a Al and Ti metals contained in the waste glass is presented. The effects of laser power on plasma temperature, emission intensity and mass of sample ablated are introduced.

The SuperCam Remote Sensing Suite for MARS 2020: Nested and Co-Aligned LIBS, Raman, and VISIR Spectroscopies, and color micro-imaging

NASA Astrophysics Data System (ADS)

Fouchet, Thierry; Wiens, Roger; Maurice, Sylvestre; Johnson, Jeffrey R.; Clegg, Samuel; Sharma, Shiv; Rull, Fernando; Montmessin, Franck; Anderson, Ryan; Beyssac, Olivier; Bonal, Lydie; Deflores, Lauren; Dromart, Gilles; Fischer, William; Forni, Olivier; Gasnault, Olivier; Grotzinger, John P.; Mangold, Nicolas; Martinez-Frias, Jesus; MacLennan, Scott; McCabe, Kevin; cais, Philippe; Nelson, Tony; Angel, Stanley; Beck, Pierre; Benzerara, Karim; Bernard, Sylvain; Bousquet, Bruno; Bridges, Nathan; Cloutis, Edward; Fabre, Cécile; Grasset, Olivier; Lanza, Nina; Lasue, Jeremie; Le Mouélic, Stéphane; Leveille, Rich; Lewin, Eric; McConnochie, Timothy H.; Melikechi, Noureddine; Meslin, Pierre-Yves; Misra, Anupam; Montagnac, Gilles; Newsom, Horton; Ollila, Ann; Pinet, Patrick; Poulet, Francois; Sobron, Pablo

2016-10-01

As chartered by the Science Definition Team, the Mars 2020 mission addresses four primary objectives: A. Characterize the processes that formed and modified the geologic record within an astrobiologically relevant ancient environment, B. Perform astrobiologically relevant investigations to determine habitability, search for materials with biosignature presentation potential, and search for evidence of past life, C. Assemble a returnable cache of samples and D. Contribute to preparation for human exploration of Mars. The SuperCam instrument, selected for the Mars 2020 rover, as a suite of four instruments, provides nested and co-aligned remote investigations: Laser Induced Breakdown Spectroscopy (LIBS), Raman spectroscopy and time-resolved fluorescence (TRF), visible and near-infrared spectroscopy (VISIR), and high resolution color imaging (RMI). SuperCam appeals broadly to the four Mars 2020 objectives.In detail, SuperCam will perform:1. Microscale mineral identification by combining LIBS elemental and VISIR mineralogical spectroscopies, especially targeting secondary minerals2. Determine the sedimental stratigraphy through color imaging and LIBS and VISIR spectroscopy3. Search for organics and bio-signatures with LIBS and Raman spectroscopy4. Quantify the volatile content of the rocks by LIBS spectroscopy to determine the degree of aquaeous alteration5. Characterize the texture of the rocks by color imaging to determine their alteration processes6. Characterize the rocks' coatings by LIBS spectroscopy7. Characterize the soil and its potential for biosignature preservation8. Monitor the odd-oxygen atmospheric chemistry.To meet these goals SuperCam will perform LIBS spectroscopy on 0.5 mm spot up to 7-meter distance, perform Raman and time-resolved fluoresence up to 12-m distance with a 0.8 mrad angular resolution, a 100 ns time gating in the 534-850 nm spectral range, acquire VISIR spectra in the range 0.4-0.85 μm with a resolution of 0.35 nm, and in the IR range over 1.3-2.6 μm, rich in mineral signatures, with a resolution of 20 nm, and provide RGB images with an angular resolution of 40 μrad over a FOV of 20 mrad.We will present the science performances of SuperCam and the forecasted operation plans.

Synthesis and application of pyridine-based ambipolar hosts: control of charge balance in organic light emitting devices (OLEDs) by chemical structure modification

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

Koech, Phillip K.; Polikarpov, Evgueni; Rainbolt, James E.

2010-11-05

Pyridine-based host materials were synthesized via Grignard metathesis of bromopyridines to provide the required organometallic reagent. The isomeric hosts (4-(9H-carbazol-9-yl)phenyl)(phenyl)(pyridin-3-yl)phosphine oxide (HM-A4), (5-(9H-carbazol-9-yl)pyridin-2-yl)diphenylphosphine oxide (HM-A5), and (5-(diphenylamino)pyridin-2-yl)diphenylphosphine oxide (HM-A6), (4-(diphenylamino)phenyl)(phenyl)(pyridin-3-yl)phosphine oxide (HM-A8) have similar frontier orbital energies. Organic light emitting devices (OLEDs) fabricated using the series of the host materials demonstrate that small structural modification of the host results in significant change in charge transporting ability.

76 FR 42733 - Sunshine Act Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-19

... hearings, as follows: Thursday, July 28, 2011: 10 a.m. Claim No. LIB-II-125, Claim No. LIB-II-126 and Claim... H. Lock, Executive Officer. [FR Doc. 2011-18198 Filed 7-15-11; 11:15 am] BILLING CODE 4410-BA-P ...

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

Shattan, Michael; Stowe, Ashley; McIntosh, Kathryn

Explore feasibility of portable LIBS and micro-XRF systems as methods of field screening for real debris; Develop a LIBS Capability to rapidly screen beads for production quality control; Complete 3D elemental mapping of surrogate debris to determine uranium and other elemental migration patterns during debris formation

Raman/LIBS Data Fusion via Two-Way Variational Autoencoders

NASA Astrophysics Data System (ADS)

Parente, M.; Gemp, I.

2018-04-01

We propose an original solution to extracting mineral abundances from Raman spectra by combining Raman data with LIBS using a novel deep learning model based on variational autoencoders and data fusion, which outperforms the current state of the art.

Calcium to phosphate ratio measurements in calcium phosphates using LIBS

NASA Astrophysics Data System (ADS)

Tariq, U.; Haider, Z.; Chaudhary, K.; Hussain, R.; Ali, J.

2018-05-01

In this study, we report the measurement of Ca/P ratio of hydroxyapatite using LIBS. Hydroxyapatite was prepared by wet chemical precipitation method with different stoichiometric ratios of Ca and P (1.5, 1.6, 1.67, 1.70, 1.80). Samples were then pelletized using KBr as a binder under a hydraulic press. Samples were irradiated with a laser beam and corresponding spectra were recorded. Spectra were further analyzed to calculate the Ca/P ratio which was then compared with the EDX for validation. LIBS results showed promise with a deviation of < 5% with the Stoichiometric ratios and EDX results.

Automated Interpretation of LIBS Spectra using a Fuzzy Logic Inference Engine

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

Jeremy J. Hatch; Timothy R. McJunkin; Cynthia Hanson

2012-02-01

Automated interpretation of laser-induced breakdown spectroscopy (LIBS) data is necessary due to the plethora of spectra that can be acquired in a relatively short time. However, traditional chemometric and artificial neural network methods that have been employed are not always transparent to a skilled user. A fuzzy logic approach to data interpretation has now been adapted to LIBS spectral interpretation. A fuzzy logic inference engine (FLIE) was used to differentiate between various copper containing and stainless steel alloys as well as unknowns. Results using FLIE indicate a high degree of confidence in spectral assignment.

Lithium tri borate (LiB3O5) embedded polymer electret for mechanical sensing application

NASA Astrophysics Data System (ADS)

Murugan, S.; Praveen, E.; Prasad, M. V. N.; Jayakumar, K.

2017-05-01

Lithium tri borate (LiB3O5) particles were synthesized by precipitation assisted high temperature solid state reaction. The particles were embedded in chitosan polymer and used as an electret. This electret was characterized for the suitability as a sensing element in vibration accelerometer. It is observed that LiB3O5 embedded electret exhibiting piezoelectric property. The electret is also giving an isolation of > 999 MΩ at 100 Vdc, 250 Vdc, 500 Vdc and 1kVdc confirms compatible for intrinsically safe sensing alternative in vibration accelerometer.

Nd:YAG-CO(2) double-pulse laser induced breakdown spectroscopy of organic films.

PubMed

Weidman, Matthew; Baudelet, Matthieu; Palanco, Santiago; Sigman, Michael; Dagdigian, Paul J; Richardson, Martin

2010-01-04

Laser-induced breakdown spectroscopy (LIBS) using double-pulse irradiation with Nd:YAG and CO(2) lasers was applied to the analysis of a polystyrene film on a silicon substrate. An enhanced emission signal, compared to single-pulse LIBS using a Nd:YAG laser, was observed from atomic carbon, as well as enhanced molecular emission from C(2) and CN. This double-pulse technique was further applied to 2,4,6-trinitrotoluene residues, and enhanced LIBS signals for both atomic carbon and molecular CN emission were observed; however, no molecular C(2) emission was detected.

30 Years of Lithium-Ion Batteries.

PubMed

Li, Matthew; Lu, Jun; Chen, Zhongwei; Amine, Khalil

2018-06-14

Over the past 30 years, significant commercial and academic progress has been made on Li-based battery technologies. From the early Li-metal anode iterations to the current commercial Li-ion batteries (LIBs), the story of the Li-based battery is full of breakthroughs and back tracing steps. This review will discuss the main roles of material science in the development of LIBs. As LIB research progresses and the materials of interest change, different emphases on the different subdisciplines of material science are placed. Early works on LIBs focus more on solid state physics whereas near the end of the 20th century, researchers began to focus more on the morphological aspects (surface coating, porosity, size, and shape) of electrode materials. While it is easy to point out which specific cathode and anode materials are currently good candidates for the next-generation of batteries, it is difficult to explain exactly why those are chosen. In this review, for the reader a complete developmental story of LIB should be clearly drawn, along with an explanation of the reasons responsible for the various technological shifts. The review will end with a statement of caution for the current modern battery research along with a brief discussion on beyond lithium-ion battery chemistries. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Spatial investigation of plasma emission from laminar diffusion methanol, ethanol, and n-propanol alcohol flames using LIBS method

NASA Astrophysics Data System (ADS)

Ghezelbash, Mahsa; Majd, Abdollah Eslami; Darbani, Seyyed Mohammad Reza; Mousavi, Seyyed Jabbar; Ghasemi, Ali; Tehrani, Masoud Kavosh

2017-01-01

Laser-induced breakdown spectroscopy (LIBS) technique is used to record some plasma emissions of different laminar diffusion methanol, ethanol, and n-propanol alcohol flames, to investigate the shapes, structures (i.e., reactants and products zones), kind, and quality of burning in different areas. For this purpose, molecular bands of CH, CH*, C2, CN, and CO as well as atomic and ionic lines of C, H, N, and O are identified, simultaneously. Experimental results indicate that the CN and C2 emissions have highest intensity in LIBS spectrum of n-propanol flame and the lowest in methanol. In addition, lowest content of CO pollution and better quality of burning process in n-propanol fuel flame toward ethanol and methanol are confirmed by comparison between their CO molecular band intensities. Moreover, variation of the signal intensity from these three flames with that from a known area of burner plate is compared. Our findings in this research advance the prior results in time-integrated LIBS combustion application and suggesting that LIBS can be used successfully with the CCD detector as a non-gated analytical tool, given its simple instrumentation needs, real-time capability applications of molecular detection in laminar diffusion flame samples, requirements.

Quantification of fluorine traces in solid samples using CaF molecular emission bands in atmospheric air Laser-Induced Breakdown Spectroscopy

NASA Astrophysics Data System (ADS)

Alvarez-Llamas, C.; Pisonero, J.; Bordel, N.

2016-09-01

Direct solid determination of trace amounts of fluorine using Laser-Induced Breakdown Spectroscopy (LIBS) is a challenging task due to the low excitation efficiency of this element. Several strategies have been developed to improve the detection capabilities, including the use of LIBS in a He atmosphere to enhance the signal to background ratios of F atomic emission lines. An alternative method is based on the detection of the molecular compounds that are formed with fluorine in the LIBS plasma. In this work, the detection of CaF molecular emission bands is investigated to improve the analytical capabilities of atmospheric air LIBS for the determination of fluorine traces in solid samples. In particular, Cu matrix samples containing different fluorine concentration (between 50 and 600 μg/g), and variable amounts of Ca, are used to demonstrate the linear relationships between CaF emission signal and F concentration. Limits of detection for fluorine are improved by more than 1 order of magnitude using CaF emission bands versus F atomic lines, in atmospheric-air LIBS. Furthermore, a toothpaste powder sample is used to validate this analytical method. Good agreement is observed between the nominal and the predicted fluorine mass-content.

Novel estimation of the humification degree of soil organic matter by laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Ferreira, Edilene Cristina; Ferreira, Ednaldo José; Villas-Boas, Paulino Ribeiro; Senesi, Giorgio Saverio; Carvalho, Camila Miranda; Romano, Renan Arnon; Martin-Neto, Ladislau; Milori, Débora Marcondes Bastos Pereira

2014-09-01

Soil organic matter (SOM) constitutes an important reservoir of terrestrial carbon and can be considered an alternative for atmospheric carbon storage, contributing to global warming mitigation. Soil management can favor atmospheric carbon incorporation into SOM or its release from SOM to atmosphere. Thus, the evaluation of the humification degree (HD), which is an indication of the recalcitrance of SOM, can provide an estimation of the capacity of carbon sequestration by soils under various managements. The HD of SOM can be estimated by using various analytical techniques including fluorescence spectroscopy. In the present work, the potential of laser-induced breakdown spectroscopy (LIBS) to estimate the HD of SOM was evaluated for the first time. Intensities of emission lines of Al, Mg and Ca from LIBS spectra showing correlation with fluorescence emissions determined by laser-induced fluorescence spectroscopy (LIFS) reference technique were used to obtain a multivaried calibration model based on the k-nearest neighbor (k-NN) method. The values predicted by the proposed model (A-LIBS) showed strong correlation with LIFS results with a Pearson's coefficient of 0.87. The HD of SOM obtained after normalizing A-LIBS by total carbon in the sample showed a strong correlation to that determined by LIFS (0.94), thus suggesting the great potential of LIBS for this novel application.

Review on recent progress of nanostructured anode materials for Li-ion batteries

NASA Astrophysics Data System (ADS)

Goriparti, Subrahmanyam; Miele, Ermanno; De Angelis, Francesco; Di Fabrizio, Enzo; Proietti Zaccaria, Remo; Capiglia, Claudio

2014-07-01

This review highlights the recent research advances in active nanostructured anode materials for the next generation of Li-ion batteries (LIBs). In fact, in order to address both energy and power demands of secondary LIBs for future energy storage applications, it is required the development of innovative kinds of electrodes. Nanostructured materials based on carbon, metal/semiconductor, metal oxides and metal phosphides/nitrides/sulfides show a variety of admirable properties for LIBs applications such as high surface area, low diffusion distance, high electrical and ionic conductivity. Therefore, nanosized active materials are extremely promising for bridging the gap towards the realization of the next generation of LIBs with high reversible capacities, increased power capability, long cycling stability and free from safety concerns. In this review, anode materials are classified, depending on their electrochemical reaction with lithium, into three groups: intercalation/de-intercalation, alloy/de-alloy and conversion materials. Furthermore, the effect of nanoscale size and morphology on the electrochemical performance is presented. Synthesis of the nanostructures, lithium battery performance and electrode reaction mechanisms are also discussed. To conclude, the main aim of this review is to provide an organic outline of the wide range of recent research progresses and perspectives on nanosized active anode materials for future LIBs.

On-line/on-site analysis of heavy metals in water and soils by laser induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Meng, Deshuo; Zhao, Nanjing; Wang, Yuanyuan; Ma, Mingjun; Fang, Li; Gu, Yanhong; Jia, Yao; Liu, Jianguo

2017-11-01

The enrichment method of heavy metal in water with graphite and aluminum electrode was studied, and combined with plasma restraint device for improving the sensitivity of detection and reducing the limit of detection (LOD) of elements. For aluminum electrode enrichment, the LODs of Cd, Pb and Ni can be as low as several ppb. For graphite enrichment, the measurement time can be less than 3 min. The results showed that the graphite enrichment and aluminum electrode enrichment method can effectively improve the LIBS detection ability. The graphite enrichment method combined with plasma spatial confinement is more suitable for on-line monitoring of industrial waste water, the aluminum electrode enrichment method can be used for trace heavy metal detection in water. A LIBS method and device for soil heavy metals analysis was also developed, and a mobile LIBS system was tested in outfield. The measurement results deduced from LIBS and ICP-MS had a good consistency. The results provided an important application support for rapid and on-site monitoring of heavy metals in soil. (Left: the mobile LIBS system for analysis of heavy metals in soils. Top right: the spatial confinement device. Bottom right: automatic graphite enrichment device for on0line analysis of heavy metals in water).

Feasibility of detection and identification of individual bioaerosols using laser-induced breakdown spectroscopy.

PubMed

Dixon, P B; Hahn, D W

2005-01-15

The detection and identification of individual bioaerosols using laser-induced breakdown spectroscopy (LIBS) is investigated using aerosolized Bacillus spores. Spores of Bacillus atrophaeous, Bacillus pumilus, and Bacillus stearothemophilus were introduced into an aerosol flow stream in a prescribed manner such that single-particle LIBS detection was realized. Bacillus spores were successfully detected based on the presence of the 393.4- and 396.9-nm calcium atomic emission lines. Statistical analyses based on the aerosol number density, the LIBS-based spore sampling frequency, and the distribution of the resulting calcium mass loadings support the conclusion of individual spore detection within single-shot laser-induced plasmas. The average mass loadings were in the range of 2-3 fg of calcium/Bacillus spore, which corresponds to a calcium mass percentage of approximately 0.5%. While individual spores were detected based on calcium emission, the resulting Bacillus spectra were free from CN emission bands, which has implications for the detection of elemental carbon, and LIBS-based detection of single spores based on the presence of magnesium or sodium atomic emission was unsuccessful. Based on the current instrumental setup and analyses, real-time LIBS-based detection and identification of single Bacillus spores in ambient (i.e., real life) conditions appears unfeasible.