light lambda max: Topics by Science.gov

Sample records for light lambda max

Color vision of the coelacanth (Latimeria chalumnae) and adaptive evolution of rhodopsin (RH1) and rhodopsin-like (RH2) pigments.

PubMed

Yokoyama, S

2000-01-01

The coelacanth, a "living fossil," lives at a depth of about 200 m near the coast of the Comoros archipelago in the Indian Ocean and receives only a narrow range of light at about 480 nm. To see the entire range of "color" the Comoran coelacanth appears to use only rod-specific RH1 and cone-specific RH2 visual pigments, with the optimum light sensitivities (lambda max) at 478 nm and 485 nm, respectively. These blue-shifted lambda max values of RH1 and RH2 pigments are fully explained by independent double amino acid replacements E122Q/A292S and E122Q/M207L, respectively. More generally, currently available mutagenesis experiments identify only 10 amino acid changes that shift the lambda max values of visual pigments more than 5 nm. Among these, D83N, E1220, M207L, and A292S are associated strongly with the adaptive blue shifts in the lambda max values of RH1 and RH2 pigments in vertebrates.
Dual color microscopic imagery of cells expressing the green fluorescent protein and a red-shifted variant.

PubMed

Yang, T T; Kain, S R; Kitts, P; Kondepudi, A; Yang, M M; Youvan, D C

1996-01-01

The green fluorescent protein (GFP) from the jellyfish, Aequorea victoria, has become a versatile reporter for monitoring gene expression and protein localization in a variety of cells and organisms. GFP emits bright green light (lambda max = 510 nm) when excited with ultraviolet (UV) or blue light (lambda max = 395 nm, minor peak at 470 nm). The chromophore in GFP is intrinsic to the primary structure of the protein, and fluorescence from GFP does not require additional gene products, substrates or other factors. GFP fluorescence is stable, species-independent and can be monitored noninvasively using the techniques of fluorescence microscopy and flow cytometry [Chalfie et al., Science 263 (1994) 802-805; Stearns, Curr. Biol. 5 (1995) 262-264]. The protein appears to undergo an autocatalytic reaction to create the fluorophore [Heim et al., Proc. Natl. Acad. Sci. USA 91 (1994) 12501-12504] in a process involving cyclization of a Tyr66 aa residue. Recently [Delagrave et al., Bio/Technology 13 (1995) 151-154], a combinatorial mutagenic strategy was targeted at aa 64 through 69, which spans the chromophore of A. victoria GFP, yielding a number of different mutants with red-shifted fluorescence excitation spectra. One of these, RSGFP4, retains the characteristic green emission spectra (lambda max = 505 nm), but has a single excitation peak (lambda max = 490 nm). The fluorescence properties of RSGFP4 are similar to those of another naturally occurring GFP from the sea pansy, Renilla reniformis [Ward and Cormier, Photobiochem. Photobiol. 27 (1978) 389-396]. In the present study, we demonstrate by fluorescence microscopy that selective excitation of A. victoria GFP and RSGFP4 allows for spectral separation of each fluorescent signal, and provides the means to image these signals independently in a mixed population of bacteria or mammalian cells.
Linear Polarization Measurements of Chromospheric Emission Lines

NASA Technical Reports Server (NTRS)

Sheeley, N. R., Jr.; Keller, C. U.

2003-01-01

We have used the Zurich Imaging Stokes Polarimeter (ZIMPOL I) with the McMath-Pierce 1.5 m main telescope on Kitt Peak to obtain linear polarization measurements of the off-limb chromosphere with a sensitivity better than 1 x 10(exp -5). We found that the off-disk observations require a combination of good seeing (to show the emission lines) and a clean heliostat (to avoid contamination by scattered light from the Sun's disk). When these conditions were met, we obtained the following principal results: 1. Sometimes self-reversed emission lines of neutral and singly ionized metals showed linear polarization caused by the transverse Zeeman effect or by instrumental cross talk from the longitudinal Zeeman effect in chromospheric magnetic fields. Otherwise, these lines tended to depolarize the scattered continuum radiation by amounts that ranged up to 0.2%. 2. Lines previously known to show scattering polarization just inside the limb (such as the Na I lambda5889 D2 and the He I lambda5876 D3 lines) showed even more polarization above the Sun's limb, with values approaching 0.7%. 3. The O I triplet at lambda7772, lambda7774, and lambda7775 showed a range of polarizations. The lambda7775 line, whose maximum intrinsic polarizability, P(sub max), is less than 1%, revealed mainly Zeeman contributions from chromospheric magnetic fields. However, the more sensitive lambda7772 (P(sub max) = 19%) and lambda7774 (P(sub max) = 29%) lines had relatively strong scattering polarizations of approximately 0.3% in addition to their Zeeman polarizations. At times of good seeing, the polarization spectra resolve into fine structures that seem to be chromospheric spicules.
[Spectral sensitivity and visual pigments of the coastal crab Hemigrapsus sanguineus].

PubMed

Shukoliukov, S A; Zak, P P; Kalamkarov, G R; Kalishevich, O O; Ostrovskiĭ, M A

1980-01-01

It has been shown that the compound eye of the coastal crab has one photosensitive pigment rhodopsin and screening pigments, black and orange one. The orange pigment has lambda max = 480 nm, rhodopsin in digitonin is stable towards hydroxylamin action, has lambda max = 490-495 nm and after bleaching is transformed into free retinene and opsin. The pigments with lambda max = 430 and 475 nm of the receptor part of the eye are also solubilized. These pigments are not photosensitive but they dissociate under the effect of hydroxylamine. The curye of spectral sensitivity of the coastal crab has the basic maximum at approximately 525 nm and the additional one at 450 nm, which seems to be provided by a combination of the visual pigment--rhodopsin (lambda max 500 nm) with a carotinoid filter (lambda max 480-490). Specific features of the visual system of coastal crab are discussed.
Ultraviolet interstellar linear polarization. 2: The wavelength dependence

NASA Technical Reports Server (NTRS)

Clayton, Geoffrey C.; Wolff, Michael J.; Allen, R. G.; Lupie, O. L.

1995-01-01

We present new ultraviolet (UV) polarimetry of the well-studied interstellar line of sight toward HD 204827 obtained with the Faint Object Spectrograph on Hubble Space Telescope. HD 204827 is of great interest because the dust along this line of sight has extremely low values of both lambda(sub max) and R(sub V). Its far-UV extinction is very large, reflecting its small R(sub V) value. In addition, we reexamine the entire sample of 14 interstellar lines of sight for which there are now UV polarization data. We find that the previously suggested relationship between lambda(sub max) and the wavelength dependence of the polarization in the UV is strongly supported by the data for this larger sample including HD 204827. Seven stars with lambda(sub max) greater than or equal to 0.54 micron agree well with an extrapolation of the Serkowski relation into the UV while seven stars with lambda(sub max) less than or equal to 0.53 micron show polarization in excess of the Serkowski extrapolation (super-Serkowski). However, the division of the observed lines of sight into Serkowski and super-Serkowski categories is artificial. In fact, the amount of polarization in the UV is correlated with a single parameter, lambda(sub max). This may indicate that there is a mean interstellar polarization law analogous to the mean interstellar extinction law of Cardelli, Calyton, & Mathis which is based on R(sub V). The data are consistent with a linear relationship between 1/lambda(sub max) and rho(UV)/rho(sub max) but more data are needed to define the functional form. We suggest that the Serkowski and super-Serkowski designations be replaced by high and low lambda(sub max) which are more physically descriptive. At the same time, we note that all seven super-Serkowski (low lambda(sub max)) stars lie in a relatively small region of the sky between l(sup II) = 90 deg - 150 deg and b = -5 deg - 15 deg. These stars all lie in or behind a spur of the local Orion spiral arm. Similarly, most of the Serkowski (high lambda(sub max) stars lie in or near the Scorpio-Centaurus OB Association. So lines of sight covering larger areas of the sky are needed to test the universality of the lambda(sub max)/UV polarization relationship. The recent discovery of warm dust near HD 197770 suggests the possibility that a mechanism other than the traditional alignment to the Galactic magnetic field may be invoked to explain its 2175 A polarization bump.
Shedding light on serpent sight: the visual pigments of henophidian snakes.

PubMed

Davies, Wayne L; Cowing, Jill A; Bowmaker, James K; Carvalho, Livia S; Gower, David J; Hunt, David M

2009-06-10

The biologist Gordon Walls proposed his "transmutation" theory through the 1930s and the 1940s to explain cone-like morphology of rods (and vice versa) in the duplex retinas of modern-day reptiles, with snakes regarded as the epitome of his hypothesis. Despite Walls' interest, the visual system of reptiles, and in particular snakes, has been widely neglected in favor of studies of fishes and mammals. By analyzing the visual pigments of two henophidian snakes, Xenopeltis unicolor and Python regius, we show that both species express two cone opsins, an ultraviolet-sensitive short-wavelength-sensitive 1 (SWS1) (lambda(max) = 361 nm) pigment and a long-wavelength-sensitive (LWS) (lambda(max) = 550 nm) pigment, providing the potential for dichromatic color vision. They also possess rod photoreceptors which express the usual rod opsin (Rh1) pigment with a lambda(max) at 497 nm. This is the first molecular study of the visual pigments expressed in the photoreceptors of any snake species. The presence of a duplex retina and the characterization of LWS, SWS1, and Rh1 visual pigments in henophidian snakes implies that "lower" snakes do not provide support for Walls' transmutation theory, unlike some "higher" (caenophidian) snakes and other reptiles, such as geckos. More data from other snake lineages will be required to test this hypothesis further.
Green fluorescent protein as a reporter of gene expression and protein localization.

PubMed

Kain, S R; Adams, M; Kondepudi, A; Yang, T T; Ward, W W; Kitts, P

1995-10-01

The green fluorescent protein (GFP) from the jellyfish Aequorea victoria is rapidly becoming an important reporter molecule for monitoring gene expression and protein localization in vivo, in situ and in real time. GFP emits bright green light (lambda max = 509 nm) when excited with UV or blue light (lambda max = 395 nm, minor peak at 470 nm). The fluorescence excitation and emission spectra of GFP are similar to those of fluorescein, and the conditions used to visualize this fluorophore are also suitable for GFP. Unlike other bioluminescent reporters, the chromophore in GFP is intrinsic to the primary structure of the protein, and GFP fluorescence does not require a substrate or cofactor. GFP fluorescence is stable, species-independent and can be monitored non-invasively in living cells and, in the case of transparent organisms, whole animals. Here we demonstrate GFP fluorescence in bacterial and mammalian cells and introduce our Living Colors line of GFP reporter vectors, GFP protein and anti-GFP antiserum. The reporter vectors for GFP include a promoterless GFP vector for monitoring the expression of cloned promoters/enhancers in mammalian cells and a series of six vectors for creating fusion protein to either the N or C terminus of GFP.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Dunach, M.; Marti, T.; Khorana, H.G.

The light-dark adaptation reactions of a set of bacteriorhodopsin (bR) mutants that affect function and color of the chromophore were examined by using visible absorption spectroscopy. The absorbance spectra of the mutants Arg-82 in equilibrium Ala (Gln), Asp-85 in equilibrium Ala (Asn, Glu), Tyr-185 in equilibrium Phe, and Asp-212 in equilibrium Ala (Asn, Glu) were measured at different pH values during and after illumination. None of these mutants exhibited a normal dark-light adaptation, which in wild-type bR causes a red shift of the visible absorption maximum from 558 nm (dark-adapted bR) to 568 nm (light-adapted bR). Instead a reversible lightmore » reaction occurs in the Asp-85 and Asp-212 mutants from a blue form with lambda max near 600 nm to a pink form with lambda max near 480 nm. This light-induced shift explains the appearance of a reversed light adaptation previously observed for the Asp-212 mutants. In the case of the Tyr-185 and Arg-82 mutants, light causes a purple-to-blue transformation similar to the effect of lowering the pH. However, the blue forms observed in these mutants are not identical to those formed by acid titration or deionization of wild-type bR. It is suggested that in all of these mutants, the chromophore has lost the ability to undergo the normal 13-cis, 15-syn to all-trans, 15-anti light-driven isomerization, which occurs in native bR. Instead these mutants may have as stable forms all-trans,syn and 13-cis,anti chromophores, which are not allowed in native bR, except transiently.« less
Spectral transmission and short-wave absorbing pigments in the fish lens--I. Phylogenetic distribution and identity.

PubMed

Thorpe, A; Douglas, R H; Truscott, R J

1993-02-01

Fish lens transmission was found to vary depending on the type and concentration of short-wave absorbing compounds present within the lens. Pigments extracted from lenses of ten species were identified as mycosporine-like amino acids (mainly palythine, palythene and asterina-330, lambda maxs around 320-360 nm) which are also thought to be present in the majority of the 120 species examined here. A novel mycosporine-like pigment with lambda max 385 nm was isolated from the lens of the flying fish, Exocoetus obtusirostris, while lenses of several closely related tropical freshwater species were found to have high concentrations of the tryptophan catabolite 3-hydroxykynurenine (lambda max 370 nm). The type of lens pigment a species possesses and its concentration depends upon both the animal's phylogenetic group and its "optical niche".
Visual pigments of marine carnivores: pinnipeds, polar bear, and sea otter.

PubMed

Levenson, David H; Ponganis, Paul J; Crognale, Michael A; Deegan, Jess F; Dizon, Andy; Jacobs, Gerald H

2006-08-01

Rod and cone visual pigments of 11 marine carnivores were evaluated. Rod, middle/long-wavelength sensitive (M/L) cone, and short-wavelength sensitive (S) cone opsin (if present) sequences were obtained from retinal mRNA. Spectral sensitivity was inferred through evaluation of known spectral tuning residues. The rod pigments of all but one of the pinnipeds were similar to those of the sea otter, polar bear, and most other terrestrial carnivores with spectral peak sensitivities (lambda(max)) of 499 or 501 nm. Similarly, the M/L cone pigments of the pinnipeds, polar bear, and otter had inferred lambda(max) of 545 to 560 nm. Only the rod opsin sequence of the elephant seal had sensitivity characteristic of adaptation for vision in the marine environment, with an inferred lambda(max) of 487 nm. No evidence of S cones was found for any of the pinnipeds. The polar bear and otter had S cones with inferred lambda(max) of approximately 440 nm. Flicker-photometric ERG was additionally used to examine the in situ sensitivities of three species of pinniped. Despite the use of conditions previously shown to evoke cone responses in other mammals, no cone responses could be elicited from any of these pinnipeds. Rod photoreceptor responses for all three species were as predicted by the genetic data.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Subramaniam, S.; Marti, T.; Khorana, H.G.

Previous studies with site-specific mutants of bacteriorhodopsin have demonstrated that replacement of Asp-85 or Arg-82 affects the absorption spectrum. Between pH 5.5 and 7, the Asp-85----Glu and Arg-82----Ala mutants exist in a pH-dependent equilibrium between purple (lambda max approximately 550/540 nm) and blue (lambda max approximately 600/590 nm) forms of the pigment. Measurement of proton transport as a function of wavelength in reconstituted vesicles shows that proton-pumping activities for the above mutants reside exclusively in their respective purple species. For both mutants, formation of the blue form with decreasing pH is accompanied by loss of proton transport activity. The Asp-85----Asnmore » mutant displays a blue chromophore (lambda max approximately 588 nm), is inactive in proton translocation from pH 5 to 7.5, and shows no transition to the purple form. In contrast, the Asp-212----Asn mutant is purple (lambda max approximately 555 nm) and shows no transition to a blue chromophore with decreasing pH. The experiments suggest that (i) the pKa of the purple-to-blue transition is directly influenced by the pKa of the carboxylate at residue 85 and (ii) the relative strengths of interaction between the protonated Schiff base, Asp-85, Asp-212, and Arg-82 make a major contribution to the regulation of color and function of bacteriorhodopsin.« less
Evolutionary replacement of UV vision by violet vision in fish.

PubMed

Tada, Takashi; Altun, Ahmet; Yokoyama, Shozo

2009-10-13

The vertebrate ancestor possessed ultraviolet (UV) vision and many species have retained it during evolution. Many other species switched to violet vision and, then again, some avian species switched back to UV vision. These UV and violet vision are mediated by short wavelength-sensitive (SWS1) pigments that absorb light maximally (lambda(max)) at approximately 360 and 390-440 nm, respectively. It is not well understood why and how these functional changes have occurred. Here, we cloned the pigment of scabbardfish (Lepidopus fitchi) with a lambda(max) of 423 nm, an example of violet-sensitive SWS1 pigment in fish. Mutagenesis experiments and quantum mechanical/molecular mechanical (QM/MM) computations show that the violet-sensitivity was achieved by the deletion of Phe-86 that converted the unprotonated Schiff base-linked 11-cis-retinal to a protonated form. The finding of a violet-sensitive SWS1 pigment in scabbardfish suggests that many other fish also have orthologous violet pigments. The isolation and comparison of such violet and UV pigments in fish living in different ecological habitats will open an unprecedented opportunity to elucidate not only the molecular basis of phenotypic adaptations, but also the genetics of UV and violet vision.
Isolation and Partial Characterization of the Pink and Blue Pigments of Pocilloporid and Acroporid Corals.

PubMed

Dove, S G; Takabayashi, M; Hoegh-Guldberg, O

1995-12-01

The compounds responsible for the pink and blue colors of two families of hermatypic corals (Pocilloporidae, Acroporidae) from the southern Great Barrier Reef were isolated and biochemically characterized. Isolation of the pink pigment from Pocillopora damicornis (named pocilloporin, {lambda}max = 560 nm, 390 nm) revealed that it was a hydrophilic protein dimer with a native molecular weight of approximately 54 kD and subunits of 28 kD. The subunits are not linked by disulfide bonds. Attempts to dissociate the chromophore from the protein proved unsuccessful. Denaturing the protein with heat (60{deg}C) or 5% sodium dodecyl sulfate (SDS) removed the 560-nm absorbance peak without introducing a detectable bathochromic shift. In acetone, ethanol, ether, and chloroform, the pigment precipitates out of solution, leaving a colorless supernatant. These properties suggest that the protein and chromophore are covalently linked. Ion analysis revealed that the pigment does not have metal ions chelated to it. Coral pigments were also isolated from pink morphs of other pocilloporids, Seriatopora hystrix ({lambda}max = 560 nm) and Stylophora pistillata ({lambda}max = 560 nm); and from bluish regions of the acroporids, Acropora formosa (blue; {lambda}max = 590 nm) and Acropora digitifera (purple; {lambda}max = 580 nm). With the exception of A. formosa, all the corals examined had pigments with the same native (54 kD) and subunit (28 kD) molecular weights as those of P. damicornis. A. formosa pigment has a native molecular weight of about 82.6 kD and three subunits of 28 kD. The pigments isolated from each of these coral species have properties similar to those described for P. damicornis. Isolation and biochemical purification of the pigment enabled the exploration of the function of the pink pigment. Three possibilities were eliminated. The compound does not act as (i) a photoprotectant for shielding the photosynthetic pigments of symbiotic zooxanthellae against excessive irradiances, (ii) a fluorescent coupling agent for amplifying the levels of photosynthetically active radiation available for resident zooxanthellae, or (iii) a UV-screen against the high UV levels of shallow tropical marine environments.
A green-yellow emitting oxyfluoride solid solution phosphor Sr[subscript 2]Ba(AlO[subscript 4]F)[subscript 1;#8722;x](SiO[subscript 5])x:Ce[superscript 3+] for thermally stable, high color rendition solid state white lighting

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

Denault, Kristin A.; George, Nathan C.; Paden, Sara R.

2012-10-23

A near-UV excited, oxyfluoride phosphor solid solution Sr{sub 1.975}Ce{sub 0.025}Ba(AlO{sub 4}F){sub 1-x}(SiO{sub 5}){sub x} has been developed for solid state white lighting applications. An examination of the host lattice, and the local structure around the Ce{sup 3+} activator ions through a combination of density functional theory, synchrotron X-ray and neutron powder diffraction and total scattering, and electron paramagnetic resonance, points to how chemical substitutions play a crucial role in tuning the optical properties of the phosphor. The maximum emission wavelength can be tuned from green ({lambda}{sub em} = 523 nm) to yellow ({lambda}{sub em} = 552 nm) by tuning themore » composition, x. Photoluminescent quantum yield is determined to be 70 {+-} 5% for some of the examples in the series. Excellent thermal properties were found for the x = 0.5 sample, with the photoluminescence intensity at 160 C only decreased to 82% of its room temperature value. Phosphor-converted LED devices fabricated using an InGaN LED ({lambda}{sub max} = 400 nm) exhibit high color rendering white light with R{sub a} = 70 and a correlated color temperature near 7000 K. The value of R{sub a} could be raised to 90 by the addition of a red component, and the correlated color temperature lowered to near 4000 K.« less
Dust in the small Magellanic Cloud. 2: Dust models from interstellar polarization and extinction data

NASA Technical Reports Server (NTRS)

Rodrigues, C. V.; Magalhaes, A. M.; Coyne, G. V.

1995-01-01

We study the dust in the Small Magellanic Cloud using our polarization and extinction data (Paper 1) and existing dust models. The data suggest that the monotonic SMC extinction curve is related to values of lambda(sub max), the wavelength of maximum polarization, which are on the average smaller than the mean for the Galaxy. On the other hand, AZV 456, a star with an extinction similar to that for the Galaxy, shows a value of lambda(sub max) similar to the mean for the Galaxy. We discuss simultaneous dust model fits to extinction and polarization. Fits to the wavelength dependent polarization data are possible for stars with small lambda(sub max). In general, they imply dust size distributions which are narrower and have smaller mean sizes compared to typical size distributions for the Galaxy. However, stars with lambda(sub max) close to the Galactic norm, which also have a narrower polarization curve, cannot be fit adequately. This holds true for all of the dust models considered. The best fits to the extinction curves are obtained with a power law size distribution by assuming that the cylindrical and spherical silicate grains have a volume distribution which is continuous from the smaller spheres to the larger cylinders. The size distribution for the cylinders is taken from the fit to the polarization. The 'typical', monotonic SMC extinction curve can be fit well with graphite and silicate grains if a small fraction of the SMC carbon is locked up in the grain. However, amorphous carbon and silicate grains also fit the data well. AZV456, which has an extinction curve similar to that for the Galaxy, has a UV bump which is too blue to be fit by spherical graphite grains.
Serum Free Light Chains in Neoplastic Monoclonal Gammopathies: Relative Under-Detection of Lambda Dominant Kappa/Lambda Ratio, and Underproduction of Free Lambda Light Chains, as Compared to Kappa Light Chains, in Patients With Neoplastic Monoclonal Gammopathies.

PubMed

Lee, Won Sok; Singh, Gurmukh

2018-07-01

Quantitative evaluation of serum free light chains is recommended for the work up of monoclonal gammopathies. Immunoglobulin light chains are generally produced in excess of heavy chains. In patients with monoclonal gammopathy, κ/λ ratio is abnormal less frequently with lambda chain lesions. This study was undertaken to ascertain if the levels of overproduction of the two light chain types and their detection rates are different in patients with neoplastic monoclonal gammopathies. Results of serum protein electrophoresis (SPEP), serum protein immunofixation electrophoresis (SIFE), urine protein electrophoresis (UPEP), urine protein immunofixation electrophoresis (UIFE), and serum free light chain assay (SFLCA) in patients with monoclonal gammopathies were examined retrospectively. The κ/λ ratios were appropriately abnormal more often in kappa chain lesions. Ratios of κ/λ were normal in about 25% of patients with lambda chain lesions in whom free homogenous lambda light chains were detectable in urine. An illustrative case suggests underproduction of free lambda light chains, in some instances. The lower prevalence of lambda dominant κ/λ ratio in lesions with lambda light chains is estimated to be due to relative under-detection of lambda dominant κ/λ ratio in about 25% of the patients and because lambda chains are not produced in as much excess of heavy chains as are kappa chains, in about 5% of the patients. The results question the medical necessity and clinical usefulness of the serum free light chain assay. UPEP/UIFE is under-utilized.
Mycosporine-like amino acids (MAAs) profile of a rice-field cyanobacterium Anabaena doliolum as influenced by PAR and UVR.

PubMed

Singh, Shailendra P; Sinha, Rajeshwar P; Klisch, Manfred; Häder, Donat-P

2008-12-01

The mycosporine-like amino acid (MAA) profile of a rice-field cyanobacterium, Anabaena doliolum, was studied under PAR and PAR + UVR conditions. The high-performance liquid chromatographic analysis of water-soluble compounds reveals the biosynthesis of three MAAs, mycosporine-glycine (lambda (max) = 310 nm), porphyra-334 (lambda (max) = 334 nm) and shinorine (lambda (max) = 334 nm), with retention times of 4.1, 3.5 and 2.3 min, respectively. This is the first report for the occurrence of mycosporine-glycine and porphyra-334 in addition to shinorine in Anabaena strains studied so far. The results indicate that mycosporine-glycine (monosubstituted) acts as a precursor for the biosynthesis of the bisubstituted MAAs shinorine and porphyra-334. Mycosporine-glycine was under constitutive control while porphyra-334 and shinorine were induced by UV-B radiation, indicating the involvement of UV-regulated enzymes in the biotransformation of MAAs. It seems that A. doliolum is able to protect its cell machinery from UVR by synthesizing a complex set of MAAs and thus is able to survive successfully during the summer in its natural brightly lit habitats.
Serum Free Light Chains in Neoplastic Monoclonal Gammopathies: Relative Under-Detection of Lambda Dominant Kappa/Lambda Ratio, and Underproduction of Free Lambda Light Chains, as Compared to Kappa Light Chains, in Patients With Neoplastic Monoclonal Gammopathies

PubMed Central

Lee, Won Sok; Singh, Gurmukh

2018-01-01

Background Quantitative evaluation of serum free light chains is recommended for the work up of monoclonal gammopathies. Immunoglobulin light chains are generally produced in excess of heavy chains. In patients with monoclonal gammopathy, κ/λ ratio is abnormal less frequently with lambda chain lesions. This study was undertaken to ascertain if the levels of overproduction of the two light chain types and their detection rates are different in patients with neoplastic monoclonal gammopathies. Methods Results of serum protein electrophoresis (SPEP), serum protein immunofixation electrophoresis (SIFE), urine protein electrophoresis (UPEP), urine protein immunofixation electrophoresis (UIFE), and serum free light chain assay (SFLCA) in patients with monoclonal gammopathies were examined retrospectively. Results The κ/λ ratios were appropriately abnormal more often in kappa chain lesions. Ratios of κ/λ were normal in about 25% of patients with lambda chain lesions in whom free homogenous lambda light chains were detectable in urine. An illustrative case suggests underproduction of free lambda light chains, in some instances. Conclusions The lower prevalence of lambda dominant κ/λ ratio in lesions with lambda light chains is estimated to be due to relative under-detection of lambda dominant κ/λ ratio in about 25% of the patients and because lambda chains are not produced in as much excess of heavy chains as are kappa chains, in about 5% of the patients. The results question the medical necessity and clinical usefulness of the serum free light chain assay. UPEP/UIFE is under-utilized. PMID:29904440
Why aye-ayes see blue.

PubMed

Melin, Amanda D; Moritz, Gillian L; Fosbury, Robert A E; Kawamura, Shoji; Dominy, Nathaniel J

2012-03-01

The capacity for cone-mediated color vision varies among nocturnal primates. Some species are colorblind, having lost the functionality of their short-wavelength-sensitive-1 (SWS1) opsin pigment gene. In other species, such as the aye-aye (Daubentonia madagascariensis), the SWS1 gene remains intact. Recent studies focused on aye-ayes indicate that this gene has been maintained by natural selection and that the pigment has a peak sensitivity (lambda(max)) of 406 nm, which is -20 nm closer to the ultraviolet region of the spectrum than in most primates. The functional significance behind the retention and unusual lambda(max) of this opsin pigment is unknown, and it is perplexing given that all mammals are presumed to be colorblind in the dark. Here we comment on this puzzle and discuss recent findings on the color vision intensity thresholds of terrestrial vertebrates with comparable optics to aye-ayes. We draw attention to the twilight activities of aye-ayes and report that twilight is enriched in short-wavelength (bluish) light. We also show that the intensity of twilight and full moonlight is probably sufficient to support cone-mediated color vision. We speculate that the intact SWS1 opsin pigment gene of aye-ayes is a crepuscular adaptation and we report on the blueness of potential visual targets, such as scent marks and the brilliant blue arils of Ravenala madagascariensis.
Mycosporine-like amino acid (MAAs) production by Heterocapasa sp. (Dinophyceae) in indoor cultures.

PubMed

Montero, Olimpio; Lubián, Luis M

2003-07-01

The possibility of using mycosporine-like amino acids (MAAs), with an apparent sunscreen function in nature, as ultraviolet radiation (UVR) blockers to prevent skin injury has been raised by diverse authors. Production of MAAs by the dinoflagellate Heterocapsa sp. (Dinophyceae) is shown here. Three major peaks with absorption maxima at 330.8, 332.0 and 333.2 nm were detected by high performance liquid chromatography (HPLC) analysis of methanolic extracts in all tested conditions. Analysis of crude extract by mass spectroscopy with electrospray ionization (MS-EI) showed a set of molecular ions ([M+H](+)) with main peaks being at m/z 242.4, 288.4, 303.3 and 333.3 u.m.a. According to these data, along with retention times, the MAA profile of Heterocapsa sp. is assumed to be composed of shinorine (lambda(max)=334 nm), mycosporine-2-glycine (lambda(max)=331 nm) and palythinol (lambda(max)=332 nm). A constitutive MAA content of about 4 microg (10(6) cells)(-1) was measured under exposure to PAR only. A maximal accumulation of MAA per culture volume of 1.1 mg l(-1) was obtained after 72 h of exposure to PAR+UVA, while the highest production rate (0.025 mg l(-1) h(-1)) was computed after 24 h of exposure to PAR+UVA+UVB.

Intermetallic communication in titanium(IV) ferrocenyldiketonates.

PubMed

Dulatas, Lea T; Brown, Seth N; Ojomo, Edema; Noll, Bruce C; Cavo, Matthew J; Holt, Paul B; Wopperer, Matthew M

2009-11-16

A tetradentate bis(ferrocenyldiketonate) ligand, Fc(2)BobH(2), is prepared via Claisen condensation of acetylferrocene and 2,2'-biphenyldiacetyl chloride, and is metalated with titanium(IV) isopropoxide to give (Fc(2)Bob)Ti(O(i)Pr)(2) in good yield. The isopropoxide groups are replaced with di(4-nitrophenyl)phosphate groups on treatment with the corresponding acid, and with chlorides on treatment with trimethylsilyl chloride. Metathesis with catechol leads to the bis(o-hydroxyphenoxide) complex rather than the chelating catecholate complex. Hydrolysis selectively gives the mu-oxo trimer (Delta,Delta,Delta)/(Lambda,Lambda,Lambda)-{(Fc(2)Bob)Ti(mu-O)}(3). The solid-state structures of the mu-oxo trimer and the bis(o-hydroxyphenoxide) complex show that the ferrocene substituents are oriented proximal to the biphenyl backbone rather than pointed out toward the exogenous groups. The complexes show dramatic changes in color depending on the bound anions, ranging from the red isopropoxide (lambda(max) = 489 nm) to the green bis(di(4-nitrophenyl)phosphate) (lambda(max) = 653 nm). The oxidation potentials of the ferrocenes show modest shifts based on the titanium environment, but the redox potentials of the two ferrocenes are never separated by more than 60 mV. These results and those of density-functional theory (DFT) calculations indicate that the titanium interacts principally with the lowest unoccupied molecular orbital (LUMO) of the ferrocenyldiketonate and very little with its highest occupied molecular orbital (HOMO).
Spectral sensitivities of the seahorses Hippocampus subelongatus and Hippocampus barbouri and the pipefish Stigmatopora argus.

PubMed

Mosk, Virginia; Thomas, Nicole; Hart, Nathan S; Partridge, Julian C; Beazley, Lyn D; Shand, Julia

2007-01-01

The Syngnathidae are specialized diurnal feeders that are known to possess a retinal fovea and use independent eye movements to locate, track, and strike individual planktonic prey items. In this study, we have investigated the spectral sensitivities of three syngnathid species: a pipefish and two seahorses. We used spectrophotometry to measure the spectral transmission properties of ocular lenses and microspectrophotometry to measure the spectral absorption characteristics of visual pigments in the retinal photoreceptors. The pipefish, Stigmatopora argus, together with the seahorse Hippocampus subelongatus, is found in "green-water" temperate coastal seagrass habitats, whereas the second seahorse, H. barbouri, originates from a "blue-water" tropical coral reef habitat. All species were found to possess short wavelength absorbing pigment(s) in their lenses, with the 50% cut-off point of S. argus and H. subelongatus at 429 and 425 nm respectively, whereas that of H. barbouri was located at 409 nm. Microspectrophotometry of the photoreceptors revealed that the rods of all three species contained visual pigment with the wavelength of maximum absorption (lambda(max)) at approximately 500 nm. The visual pigment complement of the cones varied between the species: all possessed single cones with a lambda(max) close to 460 nm but H. barbouri also possessed an additional class of single cone with lambda(max) at 430 nm. Three classes of visual pigment were found in the double cones, the lambda(max) being approximately 520, 537, and 560 nm in the two seahorses and 520, 537, and 580 nm in the pipefish. The spectral sensitivities of the syngnathids investigated here do not appear to conform to generally accepted trends for fishes inhabiting different spectral environments. The influence of the specialized feeding regime of the syngnathids is discussed in relation to our findings that ultra-violet sensitivity is apparently not necessary for zooplanktivory in certain habitats.
Low energy theorems and the unitarity bounds in the extra U(1) superstring inspired E{sub 6} models

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

Sharma, N.K.; Saxena, Pranav; Nagawat, Ashok K.

2005-11-01

The conventional method using low energy theorems derived by Chanowitz et al. [Phys. Rev. Lett. 57, 2344 (1986);] does not seem to lead to an explicit unitarity limit in the scattering processes of longitudinally polarized gauge bosons for the high energy case in the extra U(1) superstring inspired models, commonly known as {eta} model, emanating from E{sub 6} group of superstring theory. We have made use of an alternative procedure given by Durand and Lopez [Phys. Lett. B 217, 463 (1989);], which is applicable to supersymmetric grand unified theories. Explicit unitarity bounds on the superpotential couplings (identified as Yukawa couplings)more » are obtained from both using unitarity constraints as well as using renormalization group equations (RGE) analysis at one-loop level utilizing critical couplings concepts implying divergence of scalar coupling at M{sub G}. These are found to be consistent with finiteness over the entire range M{sub Z}{<=}{radical}(s){<=}M{sub G} i.e. from grand unification scale to weak scale. For completeness, the similar approach has been made use of in other models i.e., {chi}, {psi}, and {nu} models emanating from E{sub 6} and it has been noticed that at weak scale, the unitarity bounds on Yukawa couplings do not differ among E{sub 6} extra U(1) models significantly except for the case of {chi} model in 16 representations. For the case of the E{sub 6}-{eta} model ({beta}{sub E} congruent with 9.64), the analysis using the unitarity constraints leads to the following bounds on various parameters: {lambda}{sub t(max.)}(M{sub Z})=1.294, {lambda}{sub b(max.)}(M{sub Z})=1.278, {lambda}{sub H(max.)}(M{sub Z})=0.955, {lambda}{sub D(max.)}(M{sub Z})=1.312. The analytical analysis of RGE at the one-loop level provides the following critical bounds on superpotential couplings: {lambda}{sub t,c}(M{sub Z}) congruent with 1.295, {lambda}{sub b,c}(M{sub Z}) congruent with 1.279, {lambda}{sub H,c}(M{sub Z}) congruent with 0.968, {lambda}{sub D,c}(M{sub Z}) congruent with 1.315. Thus superpotential coupling values obtained by both the approaches are in good agreement. Theoretically we have obtained bounds on physical mass parameters using the unitarity constrained superpotential couplings. The bounds are as follows: (i) Absolute upper bound on top quark mass m{sub t}{<=}225 GeV (ii) the upper bound on the lightest neutral Higgs boson mass at the tree level is m{sub H{sub 2}{sup 0}}{sup tree}{<=}169 GeV, and after the inclusion of the one-loop radiative correction it is m{sub H{sub 2}{sup 0}}{<=}229 GeV when {lambda}{sub t}{ne}{lambda}{sub b} at the grand unified theory scale. On the other hand, these are m{sub H{sub 2}{sup 0}}{sup tree}{<=}159 GeV, m{sub H{sub 2}{sup 0}}{<=}222 GeV, respectively, when {lambda}{sub t}={lambda}{sub b} at the grand unified theory scale. A plausible range on D-quark mass as a function of mass scale M{sub Z{sub 2}} is m{sub D}{approx_equal}O(3 TeV) for M{sub Z{sub 2}}{approx_equal}O(1 TeV) for the favored values of tan{beta}{<=}1. The bounds on aforesaid physical parameters in the case of {chi}, {psi}, and {nu} models in the 27 representation are almost identical with those of {eta} model and are consistent with the present day experimental precision measurements.« less
{lambda}{sub b}{yields}p, {lambda} transition form factors from QCD light-cone sum rules

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

Wang Yuming; Lue Caidian; Shen Yuelong

2009-10-01

Light-cone sum rules for the {lambda}{sub b}{yields}p, {lambda} transition form factors are derived from the correlation functions expanded by the twist of the distribution amplitudes of the {lambda}{sub b} baryon. In terms of the {lambda}{sub b} three-quark distribution amplitude models constrained by the QCD theory, we calculate the form factors at small momentum transfers and compare the results with those estimated in the conventional light-cone sum rules (LCSR) and perturbative QCD approaches. Our results indicate that the two different versions of sum rules can lead to the consistent numbers of form factors responsible for {lambda}{sub b}{yields}p transition. The {lambda}{sub b}{yields}{lambda}more » transition form factors from LCSR with the asymptotic {lambda} baryon distribution amplitudes are found to be almost 1 order larger than those obtained in the {lambda}{sub b}-baryon LCSR, implying that the preasymptotic corrections to the baryonic distribution amplitudes are of great importance. Moreover, the SU(3) symmetry breaking effects between the form factors f{sub 1}{sup {lambda}{sub b}}{sup {yields}}{sup p} and f{sub 1}{sup {lambda}{sub b}}{sup {yields}}{sup {lambda}} are computed as 28{sub -8}{sup +14}% in the framework of {lambda}{sub b}-baryon LCSR.« less
Electrogenerated chemiluminescence. 59. Rhenium complexes

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

Richter, M.M.; Debad, J.D.; Bard, A.J.

Re(L)(CO){sub 3}Cl complexes (where L is 1,10-phenanthroline, 2,2`-bipyridine, or a phenanthroline or bipyridine derivative containing methyl groups) are photoluminescent in fluid solution at room temperature. In acetonitrile solutions, these complexes display one chemically reversible one-electron reduction process and one chemically irreversible oxidation process. {lambda}{sub max} for the luminescence is dependent on the nature of L, and a linear relationship between {lambda}{sub max} and the difference in electrode potentials for oxidation and reduction is evident. Electrogenerated chemiluminescence (ECL) was observed in acetonitrile solutions of these complexes (Bu{sub 4}NPF{sub 6} as electrolyte) by stepping the potential of a Pt disk working electrodemore » between potentials sufficient to form the radical anionic and cationic species. The relative amount of light produced during the anodic and cathodic pulses was dependent on the potential limits and pulse duration. ECL was also generated in the presence of coreactants, i.e., with tri-n-propylamine upon stepping the potential sufficiently positive to form the deprotonated tri-n-propylamine radical and the cationic rhenium(II) species Re{sup II}(L)(CO){sub 3}Cl{sup +}. When S{sub 2}O{sub 8}{sup 2-} was present in solution, ECL was also observed for all of the complexes upon stepping to potentials sufficient to form (Re{sup I}(L)(CO){sub 3}Cl){sup -} and the strong oxidant SO{sub 4}{sup .-}. 44 refs., 8 figs.« less
Sulfur deficiency changes mycosporine-like amino acid (MAA) composition of Anabaena variabilis PCC 7937: a possible role of sulfur in MAA bioconversion.

PubMed

Singh, Shailendra P; Klisch, Manfred; Sinha, Rajeshwar P; Häder, Donat-Peter

2010-01-01

In the present investigation we show for the first time that bioconversion of a primary mycosporine-like amino acid (MAA) into a secondary MAA is regulated by sulfur deficiency in the cyanobacterium Anabaena variabilis PCC 7937. This cyanobacterium synthesizes the primary MAA shinorine (RT = 2.2 min, lambda(max) = 334 nm) under normal conditions (PAR + UV-A + UV-B); however, under sulfur deficiency, a secondary MAA palythine-serine (RT = 3.9 min, lambda(max) = 320 nm) appears. Addition of methionine to sulfur-deficient cultures resulted in the disappearance of palythine-serine, suggesting the role of primary MAAs under sulfur deficiency in recycling of methionine by donating the methyl group from the glycine subunit of shinorine to tetrahydrofolate to regenerate the methionine from homocysteine. This is also the first report for the synthesis of palythine-serine by cyanobacteria which has so far been reported only from corals. Addition of methionine also affected the conversion of mycosporine-glycine into shinorine, consequently, resulted in the appearance of mycosporine-glycine (RT = 3.6 min, lambda(max) = 310 nm). Our results also suggest that palythine-serine is synthesized from shinorine. Based on these results we propose that glycine decarboxylase is the potential enzyme that catalyzes the bioconversion of shinorine to palythine-serine by decarboxylation and demethylation of the glycine unit of shinorine.
Retinal photoreceptors and visual pigments in Boa constrictor imperator.

PubMed

Sillman, A J; Johnson, J L; Loew, E R

2001-09-01

The photoreceptors of Boa constrictor, a boid snake of the subfamily Boinae, were examined with scanning electron microscopy and microspectrophotometry. The retina of B. constrictor is duplex but highly dominated by rods, cones comprising 11% of the photoreceptor population. The rather tightly packed rods have relatively long outer segments with proximal ends that are somewhat tapered. There are two morphologically distinct, single cones. The most common cone by far has a large inner segment and a relatively stout outer segment. The second cone, seen only infrequently, has a substantially smaller inner segment and a finer outer segment. The visual pigments of B. constrictor are virtually identical to those of the pythonine boid, Python regius. Three different visual pigments are present, all based on vitamin A(1.) The visual pigment of the rods has a wavelength of peak absorbance (lambda(max)) at 495 +/- 2 nm. The visual pigment of the more common, large cone has a lambda(max) at 549 +/- 1 nm. The small, rare cone contains a visual pigment with lambda(max) at 357 +/- 2 nm, providing the snake with sensitivity in the ultraviolet. We suggest that B. constrictor might employ UV sensitivity to locate conspecifics and/or to improve hunting efficiency. The data indicate that wavelength discrimination above 430 nm would not be possible without some input from the rods. Copyright 2001 Wiley-Liss, Inc.
Interpretation Difficulties of Serum Immunofixation Test in Immunoglobulin D Multiple Myeloma with Hidden Lambda Light Chains.

PubMed

Biaz, A; Uwingabiye, J; Rachid, A; Dami, A; Bouhsain, S; Ouzzif, Z; Idrissi, S El Machtani

2018-06-01

We report a case of immunoglobulin (Ig) D myeloma with hidden lambda light chains in a patient whose immunofixation test was very difficult to interpret: the IgD reacts with the anti-δ heavy chain antiserum but does not react with anti-lambda antiserum. The band in the D heavy chain lane is unmatched in light chain lanes and the band in lambda light chain lane migrates higher. To distinguish between heavy chain disease and immunoglobulin with "hidden" light chains, the sample was exposed to a very high concentration of anti-lambda and anti-kappa antisera for 48 hours. The serum immunofixation test of the sample treated with anti-lambda showed a decrease in the intensity of the band corresponding to D heavy chain lane as well as the modification of its mobility confirming the presence of IgD with the hidden lambda light chains. The IgD myeloma with hidden light chains remains a rare entity, hence the interest of sensitizing health professionals to be vigilant and ensure a good diagnosis. The proposed technique is useful, simple, reliable, and less laborious than those previous reported in the literature. Medical laboratories using Sebia-Hydrasys® system should be aware of the described phenomenon in order to avoid identifying an IgD myeloma as a delta heavy chain disease.
Significant Differences in Physicochemical Properties of Human Immunoglobulin Kappa and Lambda CDR3 Regions.

PubMed

Townsend, Catherine L; Laffy, Julie M J; Wu, Yu-Chang Bryan; Silva O'Hare, Joselli; Martin, Victoria; Kipling, David; Fraternali, Franca; Dunn-Walters, Deborah K

2016-01-01

Antibody variable regions are composed of a heavy and a light chain, and in humans, there are two light chain isotypes: kappa and lambda. Despite their importance in receptor editing, the light chain is often overlooked in the antibody literature, with the focus being on the heavy chain complementarity-determining region (CDR)-H3 region. In this paper, we set out to investigate the physicochemical and structural differences between human kappa and lambda light chain CDR regions. We constructed a dataset containing over 29,000 light chain variable region sequences from IgM-transcribing, newly formed B cells isolated from human bone marrow and peripheral blood. We also used a published human naïve dataset to investigate the CDR-H3 properties of heavy chains paired with kappa and lambda light chains and probed the Protein Data Bank to investigate the structural differences between kappa and lambda antibody CDR regions. We found that kappa and lambda light chains have very different CDR physicochemical and structural properties, whereas the heavy chains with which they are paired do not differ significantly. We also observed that the mean CDR3 N nucleotide addition in the kappa, lambda, and heavy chain gene rearrangements are correlated within donors but can differ between donors. This indicates that terminal deoxynucleotidyl transferase may work with differing efficiencies between different people but the same efficiency in the different classes of immunoglobulin chain within one person. We have observed large differences in the physicochemical and structural properties of kappa and lambda light chain CDR regions. This may reflect different roles in the humoral immune response.
Significant Differences in Physicochemical Properties of Human Immunoglobulin Kappa and Lambda CDR3 Regions

PubMed Central

Townsend, Catherine L.; Laffy, Julie M. J.; Wu, Yu-Chang Bryan; Silva O’Hare, Joselli; Martin, Victoria; Kipling, David; Fraternali, Franca; Dunn-Walters, Deborah K.

2016-01-01

Antibody variable regions are composed of a heavy and a light chain, and in humans, there are two light chain isotypes: kappa and lambda. Despite their importance in receptor editing, the light chain is often overlooked in the antibody literature, with the focus being on the heavy chain complementarity-determining region (CDR)-H3 region. In this paper, we set out to investigate the physicochemical and structural differences between human kappa and lambda light chain CDR regions. We constructed a dataset containing over 29,000 light chain variable region sequences from IgM-transcribing, newly formed B cells isolated from human bone marrow and peripheral blood. We also used a published human naïve dataset to investigate the CDR-H3 properties of heavy chains paired with kappa and lambda light chains and probed the Protein Data Bank to investigate the structural differences between kappa and lambda antibody CDR regions. We found that kappa and lambda light chains have very different CDR physicochemical and structural properties, whereas the heavy chains with which they are paired do not differ significantly. We also observed that the mean CDR3 N nucleotide addition in the kappa, lambda, and heavy chain gene rearrangements are correlated within donors but can differ between donors. This indicates that terminal deoxynucleotidyl transferase may work with differing efficiencies between different people but the same efficiency in the different classes of immunoglobulin chain within one person. We have observed large differences in the physicochemical and structural properties of kappa and lambda light chain CDR regions. This may reflect different roles in the humoral immune response. PMID:27729912
Diffraction-Based Optical Switch

NASA Technical Reports Server (NTRS)

Sperno, Stevan M. (Inventor); Fuhr, Peter L. (Inventor); Schipper, John F. (Inventor)

2005-01-01

Method and system for controllably redirecting a light beam, having a central wavelength lambda, from a first light-receiving site to a second light-receiving site. A diffraction grating is attached to or part of a piezoelectric substrate, which is connected to one or two controllable voltage difference sources. When a substrate voltage difference is changed and the diffraction grating length in each of one or two directions is thereby changed, at least one of the diffraction angle, the diffraction order and the central wavelength is controllably changed. A diffracted light beam component, having a given wavelength, diffraction angle and diffraction order, that is initially received at a first light receiving site (e.g., a detector or optical fiber) is thereby controllably shifted or altered and can be received at a second light receiving site. A polynomially stepped, chirped grating is used in one embodiment. In another embodiment, an incident light beam, having at least one of first and second wavelengths, lambda1 and lambda2, is received and diffracted at a first diffraction grating to provide a first diffracted beam. The first diffracted beam is received and diffracted at a second diffraction grating to produce a second diffracted beam. The second diffracted beam is received at a light-sensitive transducer, having at least first and second spaced apart light detector elements that are positioned so that, when the incident light beam has wavelength lambda1 or lambda2 (lambda1 not equal to lambda2), the second diffracted beam is received at the first element or at the second element, respectively; change in a selected physical parameter at the second grating can also be sensed or measured. A sequence of spaced apart light detector elements can be positioned along a linear or curvilinear segment with equal or unequal spacing.
Characterization of renal amyloid derived from the variable region of the lambda light chain subgroup II.

PubMed Central

Picken, M. M.; Gallo, G.; Buxbaum, J.; Frangione, B.

1986-01-01

Amyloid fibrils were extracted from the kidney of a patient (CHE) shown to have tetramers and dimers of a monoclonal lambda light chain in his serum, and whose bone marrow cells in short-term culture synthesized these forms and a smaller lambda fragment of approximately 10,000 to 12,000 daltons. Biochemical and serologic analysis of a fraction of a size (obtained from amyloid fibrils extracted from the kidney) similar to that synthesized by the bone marrow cells revealed a light chain fragment corresponding to the amino terminal end of the variable region of the lambda light chain subgroup II. The presence of similarly sized short fragments of lambda light chain in both the synthesized and deposited protein suggests that aberrant synthesis and/or proteolytic degradation may play a pathogenetic role in the process of amyloidogenesis. Images Figure 1 PMID:3089021
Determination of protein secondary structure and solvent accessibility using site-directed fluorescence labeling. Studies of T4 lysozyme using the fluorescent probe monobromobimane.

PubMed

Mansoor, S E; McHaourab, H S; Farrens, D L

1999-12-07

We report an investigation of how much protein structural information could be obtained using a site-directed fluorescence labeling (SDFL) strategy. In our experiments, we used 21 consecutive single-cysteine substitution mutants in T4 lysozyme (residues T115-K135), located in a helix-turn-helix motif. The mutants were labeled with the fluorescent probe monobromobimane and subjected to an array of fluorescence measurements. Thermal stability measurements show that introduction of the label is substantially perturbing only when it is located at buried residue sites. At buried sites (solvent surface accessibility of <40 A(2)), the destabilizations are between 3 and 5.5 kcal/mol, whereas at more exposed sites, DeltaDeltaG values of < or = 1.5 kcal/mol are obtained. Of all the fluorescence parameters that were explored (excitation lambda(max), emission lambda(max), fluorescence lifetime, quantum yield, and steady-state anisotropy), the emission lambda(max) and the steady-state anisotropy values most accurately reflect the solvent surface accessibility at each site as calculated from the crystal structure of cysteine-less T4 lysozyme. The parameters we identify allow the classification of each site as buried, partially buried, or exposed. We find that the variations in these parameters as a function of residue number reflect the sequence-specific secondary structure, the determination of which is a key step for modeling a protein of unknown structure.
Study of the chemistry of ortho- and para-biphenylnitrenes by laser flash photolysis and time-resolved IR experiments and by B3LYP and CASPT2 calculations.

PubMed

Tsao, Meng-Lin; Gritsan, Nina; James, Tammi R; Platz, Matthew S; Hrovat, David A; Borden, Weston Thatcher

2003-08-06

The photochemistry of ortho-biphenyl azide (1a) has been studied by laser flash photolysis (LFP), with UV-vis and IR detection of the transient intermediates formed. LFP (266 nm) of 1a in glassy 3-methylpentane at 77 K releases singlet ortho-biphenylnitrene (1b) (lambda(max) = 410 nm, tau = 59 +/- 6 ns), which under these conditions decays cleanly to the lower energy triplet state. In fluid solution at 298 K, 1b rapidly (tau < 10 ns) partitions between formation of isocarbazole (4) (lambda(max) = 430 nm, tau = 70 ns) and benzazirine (1e) (lambda(max) = 305 nm, tau = 12 ns). Isocarbazole 4 undergoes a 1,5-hydrogen shift, with k(H)/k(D) = 3.4 at 298 K to form carbazole 9 and smaller amounts of two other isocarbazoles (7 and 8). Benzazirine 1e ring-opens reversibly to azacycloheptatetraene (1f), which serves as a reservoir for singlet nitrene 1b. Azacycloheptatetraene 1f ultimately forms carbazole 9 on the millisecond time scale by the pathway 1f --> 1e --> 1b --> 4 --> 9. The energies of the transient intermediates and of the transition structures connecting them were successfully predicted by CASPT2/6-31G calculations. The electronic and vibrational spectra of the intermediates, computed by density functional theory, support the assignment of the transient spectra, observed in the formation of 9 from 1a.
Tertiary structure of human {Lambda}6 light chains.

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

Pokkuluri, P. R.; Solomon, A.; Weiss, D. T.

1999-01-01

AL amyloidosis is a disease process characterized by the pathologic deposition of monoclonal light chains in tissue. To date, only limited information has been obtained on the molecular features that render such light chains amyloidogenic. Although protein products of the major human V kappa and V lambda gene families have been identified in AL deposits, one particular subgroup--lambda 6--has been found to be preferentially associated with this disease. Notably, the variable region of lambda 6 proteins (V lambda 6) has distinctive primary structural features including the presence in the third framework region (FR3) of two additional amino acid residues thatmore » distinguish members of this subgroup from other types of light chains. However, the structural consequences of these alterations have not been elucidated. To determine if lambda 6 proteins possess unique tertiary structural features, as compared to light chains of other V lambda subgroups, we have obtained x-ray diffraction data on crystals prepared from two recombinant V lambda 6 molecules. These components, isolated from a bacterial expression system, were generated from lambda 6-related cDNAs cloned from bone marrow-derived plasma cells from a patient (Wil) who had documented AL amyloidosis and another (Jto) with multiple myeloma and tubular cast nephropathy, but no evident fibrillar deposits. The x-ray crystallographic analyses revealed that the two-residue insertion located between positions 68 and 69 (not between 66 and 67 as previously surmised) extended an existing loop region that effectively increased the surface area adjacent to the first complementarity determining region (CDR1). Further, an unusual interaction between the Arg 25 and Phe 2 residues commonly found in lambda 6 molecules was noted. However, the structures of V lambda 6 Wil and Jto also differed from each other, as evidenced by the presence in the latter of certain ionic and hydrophobic interactions that we posit increased protein stability and thus prevented amyloid formation.« less
Kinetic determination of propranolol in tablets by oxidation with ceric sulphate.

PubMed

Sultan, S M; Altamrah, S A; Aziz Alrahman, A M; Alzamil, I Z; Karrar, M O

1989-01-01

A simple and accurate kinetic method for the determination of propranolol has been developed. Cerium(IV) sulphate (0.5 M) is used to oxidize propranolol in 2 M sulphuric acid at room temperature to the ketone form that absorbs light at a lambda max of 525 nm. The fixed-concentration method is used by recording the exact time, t(s), taken for the reaction to reach a fixed absorbance of 0.100. The unknown concentration, c(M), of propranolol is calculated from the equation: l/t = 0 0.000217 + 0.03 c. The method has been applied to the determination of propranolol in proprietary tablets and the results were compared with those obtained by the B.P. and other standard methods.
Cross-fiber Bragg grating transducer

NASA Technical Reports Server (NTRS)

Albin, Sacharia (Inventor); Zheng, Jianli (Inventor); Lavarias, Arnel (Inventor)

2000-01-01

A transducer has been invented that uses specially-oriented gratings in waveguide a manner that allows the simultaneous measurement of physical phenomena (such as shear force, strain and temperature) in a single sensing element. The invention has a highly sensitive, linear response and also has directional sensitivity with regard to strain. The transducer has a waveguide with a longitudinal axis as well as two Bragg gratings. The transducer has a first Bragg grating associated with the waveguide that has an angular orientation .theta..sub.a relative to a perpendicular to the longitudinal axis such that 0.degree.<.theta..sub.a <.theta..sub.max. The second Bragg grating is associated with the waveguide in such a way that the angular orientation .theta..sub.b of the grating relative to a perpendicular to the longitudinal axis is (360.degree.-.theta..sub.max)<.theta..sub.b <360.degree.. The first Bragg grating can have a periodicity .LAMBDA..sub.a and the second Bragg grating can have a periodicity .LAMBDA..sub.b such that the periodicity .LAMBDA..sub.a of the first Bragg grating does not equal the periodicity .LAMBDA..sub.b of the second Bragg grating. The angle of the gratings can be such that .theta..sub.a =360.degree.-.theta..sub.b. The waveguide can assume a variety of configurations, including an optical fiber, a rectangular waveguide and a planar waveguide. The waveguide can be fabricated of a variety of materials, including silica and polymer material.
5' modification of duplex DNA with a ruthenium electron donor-acceptor pair using solid-phase DNA synthesis

NASA Technical Reports Server (NTRS)

Frank, Natia L.; Meade, Thomas J.

2003-01-01

Incorporation of metalated nucleosides into DNA through covalent modification is crucial to measurement of thermal electron-transfer rates and the dependence of these rates with structure, distance, and position. Here, we report the first synthesis of an electron donor-acceptor pair of 5' metallonucleosides and their subsequent incorporation into oligonucleotides using solid-phase DNA synthesis techniques. Large-scale syntheses of metal-containing oligonucleotides are achieved using 5' modified phosporamidites containing [Ru(acac)(2)(IMPy)](2+) (acac is acetylacetonato; IMPy is 2'-iminomethylpyridyl-2'-deoxyuridine) (3) and [Ru(bpy)(2)(IMPy)](2+) (bpy is 2,2'-bipyridine; IMPy is 2'-iminomethylpyridyl-2'-deoxyuridine) (4). Duplexes formed with the metal-containing oligonucleotides exhibit thermal stability comparable to the corresponding unmetalated duplexes (T(m) of modified duplex = 49 degrees C vs T(m) of unmodified duplex = 47 degrees C). Electrochemical (3, E(1/2) = -0.04 V vs NHE; 4, E(1/2) = 1.12 V vs NHE), absorption (3, lambda(max) = 568, 369 nm; 4, lambda(max) = 480 nm), and emission (4, lambda(max) = 720 nm, tau = 55 ns, Phi = 1.2 x 10(-)(4)) data for the ruthenium-modified nucleosides and oligonucleotides indicate that incorporation into an oligonucleotide does not perturb the electronic properties of the ruthenium complex or the DNA significantly. In addition, the absence of any change in the emission properties upon metalated duplex formation suggests that the [Ru(bpy)(2)(IMPy)](2+)[Ru(acac)(2)(IMPy)](2+) pair will provide a valuable probe for DNA-mediated electron-transfer studies.
Organic petrology of selected oil shale samples from lower Carboniferous Albert Formation, New Brunswick, Canada

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

Kalkreuth, W.; Macauley, G.

1984-04-01

Incident light microscopy was used to describe maturation and composition of organic material in oil shale samples from the Lower Carboniferous Albert Formation of New Brunswick. The maturation level was determined in normal (white) light by measuring vitrinite reflectance and in fluorescent light by measuring fluorescence spectral of alginite B. Results indicate low to intermediate maturation for all of the samples. Composition was determined by maceral analysis. Alginite B is the major organic component in all samples having significant oil potential. Oil yields obtained from the Fischer Assay process, and oil and gas potentials from Rock-Eval analyses correlate to themore » amounts of alginite B and bituminite determined in the samples. In some of the samples characterized by similar high concentrations of alginite B, decrease in Fischer Assay yields and oil and gas potentials is related to an increase in maturation, as expected by increase in the fluorescence parameter lambda/sub max/ and red/green quotient of alginite B. Incident light microscopy, particularly with fluorescent light, offers a valuable tool for the identification of the organic matter in oil shales and for the evaluation of their oil and gas potentials.« less
Phenotyping polyclonal kappa and lambda light chain molecular mass distributions in patient serum using mass spectrometry.

PubMed

Barnidge, David R; Dasari, Surendra; Ramirez-Alvarado, Marina; Fontan, Adrian; Willrich, Maria A V; Tschumper, Renee C; Jelinek, Diane F; Snyder, Melissa R; Dispenzieri, Angela; Katzmann, Jerry A; Murray, David L

2014-11-07

We previously described a microLC-ESI-Q-TOF MS method for identifying monoclonal immunoglobulins in serum and then tracking them over time using their accurate molecular mass. Here we demonstrate how the same methodology can be used to identify and characterize polyclonal immunoglobulins in serum. We establish that two molecular mass distributions observed by microLC-ESI-Q-TOF MS are from polyclonal kappa and lambda light chains using a combination of theoretical molecular masses from gene sequence data and the analysis of commercially available purified polyclonal IgG kappa and IgG lambda from normal human serum. A linear regression comparison of kappa/lambda ratios for 74 serum samples (25 hypergammaglobulinemia, 24 hypogammaglobulinemia, 25 normal) determined by microflowLC-ESI-Q-TOF MS and immunonephelometry had a slope of 1.37 and a correlation coefficient of 0.639. In addition to providing kappa/lambda ratios, the same microLC-ESI-Q-TOF MS analysis can determine the molecular mass for oligoclonal light chains observed above the polyclonal background in patient samples. In 2 patients with immune disorders and hypergammaglobulinemia, we observed a skewed polyclonal molecular mass distribution which translated into biased kappa/lambda ratios. Mass spectrometry provides a rapid and simple way to combine the polyclonal kappa/lambda light chain abundance ratios with the identification of dominant monoclonal as well as oligoclonal light chain immunoglobulins. We anticipate that this approach to evaluating immunoglobulin light chains will lead to improved understanding of immune deficiencies, autoimmune diseases, and antibody responses.

Excited state luminescence of multi-(5-phenyl-1,3,4-oxadiazo-2-yl)benzenes in an electron-donating matrix: exciplex or electroplex?

PubMed

Yang, Chih-Chiang; Hsu, Chia-Jung; Chou, Pi-Tai; Cheng, Hsu Chun; Su, Yuhlong Oliver; Leung, Man-kit

2010-01-21

Multi-(5-phenyl-1,3,4-oxadiazo-2-yl)benzenes show emission in organic solvents from ultraviolet to blue (339-447 nm). The reduction potentials E(1/2)(red) cover a large range of -2.11 V for 2,5-diphenyl-1,3,4-oxadiazole to -0.76 V for 1,2,3,4,5,6-hexa(5-phenyl-1,3,4-oxadiazo-2-yl)benzene. An unexpectedly wide spectral range of the oxadiazole (OXD) exciplex emissions in PVK is observed, ranging from 406 to 603 nm. The OXDs also exhibit similar electroluminescence (EL) when blended into polyvinylcarbazole (PVK). A linear correlation between the lambda(max) of the electroluminescence and photoluminescence is observed, implying that the emission mechanisms in both processes are similar. In addition, the linear correlation between the E(1/2)(red) versus lambda(max) of EL (eV) reflected that the term of the charge-transfer configuration of the contact electron-hole pair plays a major role in the exciplex emission. The exciplex EL of 1,2,5-tri(5-phenyl-1,3,4-oxadiazo-2-yl)benzene (5) could be as high as 1.0 cd/A. Since the exciplex emission usually has a large Stokes shift, this provides a window for us to generate duo emissions for near white light EL with high efficiency. Among the devices we tried, the device of PVK/2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazole/5/2,5,8,11-tetra-tert-butylperylene (100:40:40:4) gave EL with good current efficiency of 1.63 cd/A.
Silica-Titania Composite (STC)'s Performance in the Photocatalytic Oxidation of Polar VOCs

NASA Technical Reports Server (NTRS)

Levine, Lanfang H.; Coutts, Janelle; Richards, Jeffrey; Mazyck, David; Mazyck, David

2011-01-01

The objective of this paper is to determine the performance of a Silica-Titania Composite (STC) in the photocatalytic oxidation (PCO) of polar VOCs for potential applications in trace contaminant control within space habitats such as the ISS and CEV Orion. Tests were carried out in a bench scale STC-packed annular reactor under continuous illumination by either a UV-C germicidal lamp(lambda (sub max) = 254 nm) or UV-A fluorescent BLB (lambda(sub max) = 365 nm) for the removal of ethanol (a predominant polar VOC in the ISS cabin). The STC's performance was evaluated in terms of the ethanol mineralization rate, mineralization efficiency, and the extent of its oxidation intermediate (acetaldehyde) formation in response to the type of light source (photon energy and photon flux) and relative humidity (RH) implemented. Results demonstrated that acetaldehyde was the only quantifiable intermediate in the effluent under UV illumination, but was not found in the dark adsorption experiments. The mineralization rate increased with an increase in photon energy (UV-C greater than UV-A), even though both lamps were adjusted to emit the same incident photon flux, and also increased with increasing photon flux. However, photonic efficiency decreased as the photon flux increased. More importantly, a higher photon flux gave rise to a lower effluent acetaldehyde concentration. The effect of RH on PCO was complex and intriguing because it affected both physical adsorption and photocatalytic oxidation. In general, increasing RH caused a decrease in adsorption capacity for ethanol and reduced the mineralization efficiency with a concomitant higher acetaldehyde evolution rate. The effect of RH was less profound than that of photon flux.
A single amino acid substitution in the variable region of the light chain specifically blocks immunoglobulin secretion.

PubMed Central

Dul, J L; Argon, Y

1990-01-01

Although immunoglobulin light chains are usually secreted in association with heavy chains, free light chains can be secreted by lymphocytes. To identify the structural features of light chains that are essential for their secretion, we mutated a conserved sequence in the variable domain of a lambda I light chain. The effects of the mutations on secretion were assayed by transient expression in COS-1 cells. One mutant (AV60), which replaced Ala-60 with Val, was secreted as efficiently as wild-type lambda I by transfected COS-1 cells. This result was not surprising because secreted lambda II chains contain valine in this position. However, a second lambda I mutant (AV60FS62), which replaced Phe-62 with Ser as well as Ala-60 with Val, was not secreted. This mutant was arrested in the endoplasmic reticulum, as judged by immunofluorescence and by its association with a lumenal endoplasmic reticulum protein, immunoglobulin heavy chain binding protein (BiP). The defect in secretion was not due to gross misfolding of the lambda I chain, since cells cotransfected with AV60FS62 and an immunoglobulin heavy chain gene produced functional antigen-binding antibodies. These assembled IgM molecules were still not secreted. Hence, the replacement of Phe-62 with Ser specifically affects a determinant on the lambda I light chain that is necessary for the intracellular transport of this molecule. Images PMID:2122454
Somatic diversification of chicken immunoglobulin light chains by point mutations.

PubMed

Parvari, R; Ziv, E; Lantner, F; Heller, D; Schechter, I

1990-04-01

The light-chain locus of chicken has 1 functional V lambda 1 gene, 1 J gene, and 25 pseudo-V lambda-genes (where V = variable and J = joining). A major problem is which somatic mechanisms expand this extremely limited germ-line information to generate many different antibodies. Weill's group [Reynaud, C. A., Anquez, V., Grimal, H. & Weill, J. C. (1987) Cell 48, 379-388] has shown that the pseudo-V lambda-genes diversify the rearranged V lambda 1 by gene conversion. Here we demonstrate that chicken light chains are further diversified by somatic point mutations and by V lambda 1-J flexible joining. Somatic point mutations were identified in the J and 3' noncoding DNA of rearranged light-chain genes of chicken. These regions were analyzed because point mutations in V lambda 1 are obscured by gene conversion; the J and 3' noncoding DNA are presented in one copy per haploid genome and are not subject to gene conversion. In rodents point mutations occur as frequently in the V-J coding regions as in the adjacent flanking DNA. Therefore, we conclude that somatic point mutations diversify the V lambda 1 of chicken. The frequency (0-1%) and distribution of the mutations (decreasing in number with increased distance from the V lambda 1 segment) in chicken were as observed in rodents. Sequence variability at the V lambda 1-J junctions could be attributed to imprecise joining of the V lambda 1 and J genes. The modification by gene conversion of rearranged V lambda 1 genes in the bursa was similar in chicken aged 3 months (9.5%) or 3 weeks (9.1%)--i.e., gene conversion that generates the preimmune repertoire in the bursa seems to level off around 3 weeks of age. This preimmune repertoire can be further diversified by somatic point mutations that presumably lead to the formation of antibodies with increased affinity. A segment with structural features of a matrix association region [(A + T)-rich and four topoisomerase II binding sites] was identified in the middle of the J-C lambda intron (where C = constant).
[A novel yellow organic light-emitting device].

PubMed

Ma, Chen; Wang, Hua; Hao, Yu-Ying; Gao, Zhi-Xiang; Zhou, He-Feng; Xu, Bing-She

2008-07-01

The fabrication of a novel organic yellow-light-emitting device using Rhodamine B as dopant with double quantum-well (DQW) structure was introduced in the present article. The structure and thickness of this device is ITO/CuPc (6 nm) /NPB (20 nm) /Alq3 (3 nm)/Alq3 : Rhodamine B (3 nm) /Alq3 (3 nm) /Al q3 : Rhodamine B(3 nm) /Alq3 (30 nm) /Liq (5 nm)/Al (30 nm). With the detailed investigation of electroluminescence of the novel organic yellow-light-emitting device, the authors found that the doping concentration of Rhodamine B (RhB) had a very big influence on luminance and efficiency of the organic yellow-light-emitting device. When doping concentration of Rhodamine B (RhB) was 1.5 wt%, the organic yellow-light-emitting device was obtained with the maximum current efficiency of 1.526 cd x A(-1) and the maximum luminance of 1 309 cd x m(-2). It can be seen from the EL spectra of the devices that there existed energy transferring from Alq3 to RhB in the organic light-emitting layers. When the doping concentration of RhB increased, lambda(max) of EL spectra redshifted obviously. The phenomenon was attributed to the Stokes effect of quantum wells and self-polarization of RhB dye molecules.
On pulse duration of self-terminating lasers

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

Bokhan, P A

2011-02-28

The problem of the maximum pulse duration {tau}{sub max} of self-terminating lasers is considered. It is shown that the duration depends on the transition probability in the laser channel, on the decay rate of the resonant state in all other channels, and on the excitation rate of the metastable state. As a result, {tau}{sub max} is found to be significantly shorter than previously estimated. The criteria for converting the 'self-terminating' lasing to quasi-cw lasing are determined. It is shown that in the case of nonselective depopulation of the metastable state, for example in capillary lasers or in a fast flowmore » of the active medium gas, it is impossible to obtain continuous lasing. Some concrete examples are considered. It is established that in several studies of barium vapour lasers ({lambda} = 1.5 {mu}m) and nitrogen lasers ({lambda} = 337 nm), collisional lasing is obtained by increasing the relaxation rate of the metastable state in collisions with working particles (barium atoms and nitrogen molecules). (lasers)« less
Diversity of immunoglobulin lambda light chain gene usage over developmental stages in the horse.

PubMed

Tallmadge, Rebecca L; Tseng, Chia T; Felippe, M Julia B

2014-10-01

To further studies of neonatal immune responses to pathogens and vaccination, we investigated the dynamics of B lymphocyte development and immunoglobulin (Ig) gene diversity. Previously we demonstrated that equine fetal Ig VDJ sequences exhibit combinatorial and junctional diversity levels comparable to those of adult Ig VDJ sequences. Herein, RACE clones from fetal, neonatal, foal, and adult lymphoid tissue were assessed for Ig lambda light chain combinatorial, junctional, and sequence diversity. Remarkably, more lambda variable genes (IGLV) were used during fetal life than later stages and IGLV gene usage differed significantly with time, in contrast to the Ig heavy chain. Junctional diversity measured by CDR3L length was constant over time. Comparison of Ig lambda transcripts to germline revealed significant increases in nucleotide diversity over time, even during fetal life. These results suggest that the Ig lambda light chain provides an additional dimension of diversity to the equine Ig repertoire. Copyright © 2014 Elsevier Ltd. All rights reserved.
Beyond [lambda][subscript max] Part 2: Predicting Molecular Color

ERIC Educational Resources Information Center

Williams, Darren L.; Flaherty, Thomas J.; Alnasleh, Bassam K.

2009-01-01

A concise roadmap for using computational chemistry programs (i.e., Gaussian 03W) to predict the color of a molecular species is presented. A color-predicting spreadsheet is available with the online material that uses transition wavelengths and peak-shape parameters to predict the visible absorbance spectrum, transmittance spectrum, chromaticity…
Fluorescent Dendritic Micro-Hydrogels: Synthesis, Analysis and Use in Single-Cell Detection.

PubMed

Christadore, Lisa; Grinstaff, Mark W; Schaus, Scott E

2018-04-18

Hydrogels are of keen interest for a wide range of medical and biotechnological applications including as 3D substrate structures for the detection of proteins, nucleic acids, and cells. Hydrogel parameters such as polymer wt % and crosslink density are typically altered for a specific application; now, fluorescence can be incorporated into such criteria by specific macromonomer selection. Intrinsic fluorescence was observed at λ max 445 nm from hydrogels polymerized from lysine and aldehyde- terminated poly(ethylene glycol) macromonomers upon excitation with visible light. The hydrogel’s photochemical properties are consistent with formation of a nitrone functionality. Printed hydrogels of 150 μm were used to detect individual cell adherence via a decreased in fluorescence. The use of such intrinsically fluorescent hydrogels as a platform for cell sorting and detection expands the current repertoire of tools available.
Assessment of Intrathecal Free Light Chain Synthesis: Comparison of Different Quantitative Methods with the Detection of Oligoclonal Free Light Chains by Isoelectric Focusing and Affinity-Mediated Immunoblotting.

PubMed

Zeman, David; Kušnierová, Pavlína; Švagera, Zdeněk; Všianský, František; Byrtusová, Monika; Hradílek, Pavel; Kurková, Barbora; Zapletalová, Olga; Bartoš, Vladimír

2016-01-01

We aimed to compare various methods for free light chain (fLC) quantitation in cerebrospinal fluid (CSF) and serum and to determine whether quantitative CSF measurements could reliably predict intrathecal fLC synthesis. In addition, we wished to determine the relationship between free kappa and free lambda light chain concentrations in CSF and serum in various disease groups. We analysed 166 paired CSF and serum samples by at least one of the following methods: turbidimetry (Freelite™, SPAPLUS), nephelometry (N Latex FLC™, BN ProSpec), and two different (commercially available and in-house developed) sandwich ELISAs. The results were compared with oligoclonal fLC detected by affinity-mediated immunoblotting after isoelectric focusing. Although the correlations between quantitative methods were good, both proportional and systematic differences were discerned. However, no major differences were observed in the prediction of positive oligoclonal fLC test. Surprisingly, CSF free kappa/free lambda light chain ratios were lower than those in serum in about 75% of samples with negative oligoclonal fLC test. In about a half of patients with multiple sclerosis and clinically isolated syndrome, profoundly increased free kappa/free lambda light chain ratios were found in the CSF. Our results show that using appropriate method-specific cut-offs, different methods of CSF fLC quantitation can be used for the prediction of intrathecal fLC synthesis. The reason for unexpectedly low free kappa/free lambda light chain ratios in normal CSFs remains to be elucidated. Whereas CSF free kappa light chain concentration is increased in most patients with multiple sclerosis and clinically isolated syndrome, CSF free lambda light chain values show large interindividual variability in these patients and should be investigated further for possible immunopathological and prognostic significance.
Quadrupole deformation ({beta},{gamma}) of light {Lambda} hypernuclei in a constrained relativistic mean field model: Shape evolution and shape polarization effect of the {Lambda} hyperon

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

Lu Bingnan; Zhao Enguang; Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000

2011-07-15

The shapes of light normal nuclei and {Lambda} hypernuclei are investigated in the ({beta},{gamma}) deformation plane by using a newly developed constrained relativistic mean field (RMF) model. As examples, the results of some C, Mg, and Si nuclei are presented and discussed in details. We found that for normal nuclei the present RMF calculations and previous Skyrme-Hartree-Fock models predict similar trends of the shape evolution with the neutron number increasing. But some quantitative aspects from these two approaches, such as the depth of the minimum and the softness in the {gamma} direction, differ a lot for several nuclei. For {Lambda}more » hypernuclei, in most cases, the addition of a {Lambda} hyperon alters slightly the location of the ground state minimum toward the direction of smaller {beta} and softer {gamma} in the potential energy surface E{approx}({beta},{gamma}). There are three exceptions, namely, {sub {Lambda}}{sup 13}C, {sub {Lambda}}{sup 23}C, and {sub {Lambda}}{sup 31}Si in which the polarization effect of the additional {Lambda} is so strong that the shapes of these three hypernuclei are drastically different from their corresponding core nuclei.« less
Characterization of an LED based photoreactor to degrade 4-chlorophenol in an aqueous medium using coumarin (C-343) sensitized TiO2.

PubMed

Ghosh, Jyoti P; Langford, Cooper H; Achari, Gopal

2008-10-16

A detailed performance evaluation of a simple high intensity LED based photoreactor exploiting a narrow wavelength range of the LED to match the spectrum of a dye in a photocatalysis system is reported. A dye sensitized (coumarin-343, lambda max = 446 nm) TiO 2 photocatalyst was used for the degradation of 4-chlorophenol (4-CP) in an aqueous medium using the 436 nm LED based photoreactor. The LED reactor performed competitively with a conventional multilamp reactor and sunlight in the degradation of 4-CP. Light intensities entering the reaction vessel were measured by conventional ferrioxalate actinometry. The results can be fitted by approximate first order kinetic behavior in this system. Hydroxyl radicals were detected by spin trapping EPR, and effects of OH radical quenchers on kinetics suggest that the reaction is initiated by these radicals or their equivalents. LEDs operating at competitive intensities offer a number of advantages to the photochemist or the environmental engineer via long life, efficient current to light conversion, narrow bandwidth, forward directed output, and direct current power for remote operation. Matching light source spectrum to chromophore is a key.
Intense Photosensitized Emission from Stoichiometric Compounds Featuring Mn(2+) in Seven- and Eightfold Coordination Environments.

PubMed

Reid, Howard O. N.; Kahwa, Ishenkumba A.; White, Andrew J. P.; Williams, David J.

1998-07-27

Synthetic, structural and luminescence studies of stoichiometric crown ether compounds of Mn(2+) in well-defined coordination environments were undertaken in an effort to understand the origin of emitting crystal defects found in cubic F23 [(K18C6)(4)MnBr(4)][TlBr(4)](2) crystals (Fender, N. S.; et al. Inorg. Chem. 1997, 36, 5539). The new compound [Mn(12C4)(2)][MnBr(4)](2)[N(CH(3))(4)](2) (3) features Mn(2+) ions in eight- and fourfold coordination environments of [Mn(12C4)(2)](2+) and MnBr(4)(2)(-) respectively, while Mn(2+) in [Mn(15C5)(H(2)O)(2)][TlBr(5)] (4) is in the sevenfold coordination polyhedron of [Mn(15C5)(H(2)O)(2)](2+). Crystal data for 3: monoclinic, P2(1)/c (No. 14); a = 14.131(3) Å, b = 12.158(1) Å, c = 14.239(2) Å, beta = 110.37(1) degrees, Z = 2, R1 = 0.039 and wR2 = 0.083. For 3, long-lived emission (77 K decay rate approximately 3 x 10 s(-)(1)) from [Mn(12C4)(2)](2+) (the first for eight-coordinate Mn(2+) in stoichiometric compounds) is observed (lambda(max) approximately 546 nm) along with that of the sensitizing MnBr(4)(2)(-) (lambda(max) approximately 513 nm), which is partially quenched. Emission from the seven-coordinate [Mn(15C5)(H(2)O)(2)](2+) species of 4 and [Mn(15C5)(H(2)O)(2)][MnBr(4)] (the first for seven-coordinate Mn(2+) in stoichiometric compounds) peaks at lambda(max) approximately 592 nm. Unusually intense absorptions attributable to the seven-coordinate species are observed at 317 ((2)T(2)((2)I) <-- (6)A(1)), 342 ((4)T(1)((4)P) <-- (6)A(1)), 406 ((4)E((4)G) <-- (6)A(1)), and 531 ((4)T(1)((4)G) <-- (6)A(1)) nm.
Strong shock waves and nonequilibrium response in a one-dimensional gas: a Boltzmann equation approach.

PubMed

Hurtado, Pablo I

2005-10-01

We investigate the nonequilibrium behavior of a one-dimensional binary fluid on the basis of Boltzmann equation, using an infinitely strong shock wave as probe. Density, velocity, and temperature profiles are obtained as a function of the mixture mass ratio mu. We show that temperature overshoots near the shock layer, and that heavy particles are denser, slower, and cooler than light particles in the strong nonequilibrium region around the shock. The shock width omega(mu), which characterizes the size of this region, decreases as omega(mu) approximately mu(1/3) for mu-->0. In this limit, two very different length scales control the fluid structure, with heavy particles equilibrating much faster than light ones. Hydrodynamic fields relax exponentially toward equilibrium: phi(chi) approximately exp[-chi/lambda]. The scale separation is also apparent here, with two typical scales, lambda1 and lambda2, such that lambda1 approximately mu(1/2 as mu-->0, while lambda2, which is the slow scale controlling the fluid's asymptotic relaxation, increases to a constant value in this limit. These results are discussed in light of recent numerical studies on the nonequilibrium behavior of similar one-dimensional binary fluids.
Assessment of Intrathecal Free Light Chain Synthesis: Comparison of Different Quantitative Methods with the Detection of Oligoclonal Free Light Chains by Isoelectric Focusing and Affinity-Mediated Immunoblotting

PubMed Central

Kušnierová, Pavlína; Švagera, Zdeněk; Všianský, František; Byrtusová, Monika; Hradílek, Pavel; Kurková, Barbora; Zapletalová, Olga; Bartoš, Vladimír

2016-01-01

Objectives We aimed to compare various methods for free light chain (fLC) quantitation in cerebrospinal fluid (CSF) and serum and to determine whether quantitative CSF measurements could reliably predict intrathecal fLC synthesis. In addition, we wished to determine the relationship between free kappa and free lambda light chain concentrations in CSF and serum in various disease groups. Methods We analysed 166 paired CSF and serum samples by at least one of the following methods: turbidimetry (Freelite™, SPAPLUS), nephelometry (N Latex FLC™, BN ProSpec), and two different (commercially available and in-house developed) sandwich ELISAs. The results were compared with oligoclonal fLC detected by affinity-mediated immunoblotting after isoelectric focusing. Results Although the correlations between quantitative methods were good, both proportional and systematic differences were discerned. However, no major differences were observed in the prediction of positive oligoclonal fLC test. Surprisingly, CSF free kappa/free lambda light chain ratios were lower than those in serum in about 75% of samples with negative oligoclonal fLC test. In about a half of patients with multiple sclerosis and clinically isolated syndrome, profoundly increased free kappa/free lambda light chain ratios were found in the CSF. Conclusions Our results show that using appropriate method-specific cut-offs, different methods of CSF fLC quantitation can be used for the prediction of intrathecal fLC synthesis. The reason for unexpectedly low free kappa/free lambda light chain ratios in normal CSFs remains to be elucidated. Whereas CSF free kappa light chain concentration is increased in most patients with multiple sclerosis and clinically isolated syndrome, CSF free lambda light chain values show large interindividual variability in these patients and should be investigated further for possible immunopathological and prognostic significance. PMID:27846293
Rayleigh, the unit for light radiance.

PubMed

Baker, D J

1974-09-01

A 0.7% accurate formula is derived for the easy conversion of power spectral radiance L(lambda) in W cm(-2) sr(-1) microm(-1)to rayleigh spectral radiance R(lambda) in rayleigh/microm, R(lambda) = 2pilambdaL(lambda) x 10(13), where the wavelength lambda is in microm. The rationale for the rayleigh unit is discussed in terms of a photon rate factor and a solid angle factor. The latter is developed in terms of an equivalence theorem about optical receivers and extended sources, and the concept is extended to the computation of photon volume emission rates from altitude profiles of zenith radiance.
Structures Of Magnetically-Supported Filaments And Their Appearance In The Linear Polarization

NASA Astrophysics Data System (ADS)

Tomisaka, Kohji

2017-10-01

Dust thermal emissions observed with Herschel have revealed that interstellar molecular clouds consist of many filaments. Polarization observation of interstellar extinctions in the optical and near IR wavelengths shows that the dense filaments are extending perpendicular to the interstellar magnetic field. Magnetohydrostatic structures of such filaments are studied. It is well known that a hydrostatic filament without magnetic field has a maximum line mass of ¥lambda_max=2c_s^2/G (c_s:the isothermal sound speed and G: the gravitational constant). On the other hand, the magnetically-supported maximum line mass increases in proportion to the magnetic flux per unit length threading the filament (¥phi), as ¥lambda_max 2c_s^2/G + ¥phi/(2¥pi G^1/2). Comparison is made with 3D clouds. Stability of these magnetized filaments is studied using time-dependent 3D MHD simulations to discuss star formation in the filaments. Polarization pattern expected for the magnetically subcritical filaments is calculated. The distribution function of the angle between B-field and the axis of the filament, which is obtained with Planck Satellite, is compared with this mock observation.
Heterogeneous and monoclonal helper T cells induce similar anti-(4-hydroxy-3-nitrophenyl)acetyl (NP) antibody populations in the primary adoptive response. II. Lambda light chain dominance and idiotope expression.

PubMed

Smith, F I; Tesch, H; Rajewsky, K

1984-02-01

When the hapten (4-hydroxy-3-nitrophenyl)acetyl (NP) is presented on different carrier molecules, different anti-NP antibody responses are stimulated. On stimulation with NP-lipopolysaccharide (LPS) [T-independent type 1 (TI-1) antigen] kappa + antibodies are the major population, whereas on stimulation with NP-Ficoll [T-independent type 2 (TI-2) antigen], NP-keyhole limpet hemocyanin (KLH) or NP-chicken gamma globulin (CG) [T-dependent (TD) antigens], lambda 1+ antibodies dominate. The relative contribution of idiotopes Ac38 or Ac146 to the lambda 1+ anti-NP response was also different on comparison of TI-1 with TI-2 or TD anti-NP responses. We investigated whether light chain- or idiotype-specific T cells are responsible for these differences. Analysis of the anti-NP response of nude mice after immunization with NP-Ficoll showed lambda 1 dominance. Likewise primary adoptive transfer experiments using carrier-specific T cell lines to reconstitute the TD anti-NP response to NP-KLH or NP-CG, showed that help from carrier-specific T cells alone is capable of stimulating the characteristic lambda 1 dominant response. No significant difference could be found in the levels of Ac38 and Ac146 idiotope expression between mice reconstituted with splenic T cells and those reconstituted with T cell lines. These results suggest that light chain- or idiotype-specific T cells are required neither for the production of lambda 1 light chain dominance, nor for the appearance of idiotopes characteristic of the primary anti-NP response. The possible reasons for differences seen in both light chain and idiotope expression between primary anti-NP responses to the TI-1 antigen NP-LPS and those to TD or TI-2 antigens are discussed.
First Astronomical Use of Multiplexed Transition Edge Sensor Bolometers

NASA Technical Reports Server (NTRS)

Staguhn, J. G.; Ames, T. A.; Benford, D. J.; Chervenak, J. A.; Grossman, E. N.; Irwin, K. D.; Khan, S. A.; Maffei, B.; Moseley, S. H.; Pajot, F.

2004-01-01

We present performance results based on the first astronomical use of multiplexed superconducting bolometers. The Fabry-Perot Interferometer Bolometer Research Experiment (FIBRE) is a broadband submillimeter spectrometer that achieved first light in June 2001 at the Caltech Submillimeter Observatory (CSO). FIBRE's detectors are superconducting transition edge sensor (TES) bolometers read out by a SQUID multiplexer. The Fabry-Perot uses a low resolution grating to order sort the incoming light. A linear bolometer array consisting of 16 elements detects this dispersed light, capturing 5 orders simultaneously from one position on the sky. With tuning of the Fabry-Perot over one free spectral range, a spectrum covering Delta lambda/lambda = 1/7 at a resolution of delta lambda/lambda approx. 1/1200 can be acquired. This spectral resolution is sufficient to resolve Doppler-broadened line emission from external galaxies. FIBRE operates in the 350 m and 450 m bands. These bands cover line emission from the important star formation tracers neutral carbon (CI) and carbon monoxide (CO). We have verified that the multiplexed bolometers are photon noise limited even with the low power present in moderate resolution spectrometry.
The Tautomeric Half-reaction of BphD, a C-C Bond Hydrolase Kinetic and Structural Evidence Supporting a Key Role for Histidine 265 of the Catalytic triad

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

Horsman, Geoff P.; Bhowmik, Shiva; Seah, Stephen Y.K.

2010-01-07

BphD of Burkholderia xenovorans LB400 catalyzes an unusual C-C bond hydrolysis of 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) to afford benzoic acid and 2-hydroxy-2,4-pentadienoic acid (HPD). An enol-keto tautomerization has been proposed to precede hydrolysis via a gem-diol intermediate. The role of the canonical catalytic triad (Ser-112, His-265, Asp-237) in mediating these two half-reactions remains unclear. We previously reported that the BphD-catalyzed hydrolysis of HOPDA ({lambda}{sub max} is 434 nm for the free enolate) proceeds via an unidentified intermediate with a red-shifted absorption spectrum ({lambda}{sub max} is 492 nm) (Horsman, G. P., Ke, J., Dai, S., Seah, S. Y. K., Bolin, J. T.,more » and Eltis, L. D. (2006) Biochemistry 45, 11071-11086). Here we demonstrate that the S112A variant generates and traps a similar intermediate ({lambda}{sub max} is 506 nm) with a similar rate, 1/{tau} {approx} 500 s{sup -1}. The crystal structure of the S112A:HOPDA complex at 1.8-{angstrom} resolution identified this intermediate as the keto tautomer, (E)-2,6-dioxo-6-phenyl-hex-3-enoate. This keto tautomer did not accumulate in either the H265A or the S112A/H265A double variants, indicating that His-265 catalyzes tautomerization. Consistent with this role, the wild type and S112A enzymes catalyzed tautomerization of the product HPD, whereas H265A variants did not. This study thus identifies a keto intermediate, and demonstrates that the catalytic triad histidine catalyzes the tautomerization half-reaction, expanding the role of this residue from its purely hydrolytic function in other serine hydrolases. Finally, the S112A:HOPDA crystal structure is more consistent with hydrolysis occurring via an acyl-enzyme intermediate than a gem-diol intermediate as solvent molecules have poor access to C6, and the closest ordered water is 7{angstrom} away.« less

Synthesis of a metal oxide with a room-temperature photoreversible phase transition.

PubMed

Ohkoshi, Shin-Ichi; Tsunobuchi, Yoshihide; Matsuda, Tomoyuki; Hashimoto, Kazuhito; Namai, Asuka; Hakoe, Fumiyoshi; Tokoro, Hiroko

2010-07-01

Photoinduced phase-transition materials, such as chalcogenides, spin-crossover complexes, photochromic organic compounds and charge-transfer materials, are of interest because of their application to optical data storage. Here we report a photoreversible metal-semiconductor phase transition at room temperature with a unique phase of Ti(3)O(5), lambda-Ti(3)O(5). lambda-Ti(3)O(5) nanocrystals are made by the combination of reverse-micelle and sol-gel techniques. Thermodynamic analysis suggests that the photoinduced phase transition originates from a particular state of lambda-Ti(3)O(5) trapped at a thermodynamic local energy minimum. Light irradiation causes reversible switching between this trapped state (lambda-Ti(3)O(5)) and the other energy-minimum state (beta-Ti(3)O(5)), both of which are persistent phases. This is the first demonstration of a photorewritable phenomenon at room temperature in a metal oxide. lambda-Ti(3)O(5) satisfies the operation conditions required for a practical optical storage system (operational temperature, writing data by short wavelength light and the appropriate threshold laser power).
Preferential use of lambda light chains is associated with defective mouse antibody responses to the capsular polysaccharide of Neisseria meningitidis group B.

PubMed

Colino, Jesus; Outschoorn, Ingrid

2004-01-01

The capsular polysaccharide of Neisseria meningitidis group B (CpsB) is a very poor immunogen in mammals; this has been considered to be due to the induction of tolerance to cross-reactive host glycoconjugates. It has hampered the development of an effective vaccine against this meningococcal group for many years. Syngeneic populations have a similar tolerogenic background. Thus, we used the variability in ability to mount CpsB-specific immunoglobulin (Ig) responses of individuals from these populations to reveal underlying mechanisms to tolerance contributing to the poor immunogenicity of CpsB. Here we analyze by ELISA, the individual CpsB-specific Ig response of BALB/c and other syngeneic mice to immunization with intact bacteria, using the distribution of light chains as a direct indicator of the repertoire dynamics of the response. Although approximately 96% of anti-CpsB Ig bear kappa-light chains, BALB/c mouse populations were heterogeneous in the light chain composition of their individual anti-CpsB Ig responses. The proportion of kappa and lambda-light chains used for anti-CpsB Ig was a private characteristic that remained relatively constant, for each individual, through repetitive immunizations regardless of the bacterial stimuli size. Despite the prevalence of individual use of kappa-light chains, 5% of BALB/c mice showed restricted usage of lambda-light chains in their CpsB-specific Ig responses, and an additional 11% use them significantly. The preferential use of lambda-light chains in these mice was strongly associated with defective IgM, and absent or barely detectable IgG anti-CpsB responses even after repetitive bacterial immunization. We conclude that differences in the private repertoire of specific Ig also contribute to mouse unresponsiveness to CpsB.
OAO-2 observations of the zodiacal light

NASA Technical Reports Server (NTRS)

Lillie, C. F.

1972-01-01

Photometric measurements of the night sky brightness have been obtained at twelve wavelengths between 1000 A and 4300 A from above the earth's atmosphere. A preliminary analysis of the data reveals a component of the sky brightness with ecliptic symmetry and an intensity distribution similar to that of the zodiacal light. The ultraviolet spectrum of the zodiacal light can be closely approximated with a two component model in which one component has an albedo proportional to the wavelength lambda and the other component has a scattering efficiency proportional to lambda to lbe minus 19 power.
The lambda mechanism of the 0nbb-decay

NASA Astrophysics Data System (ADS)

Šimkovic, Fedor; Štefánik, Dušan; Dvornický, Rastislav

2017-11-01

The lambda mechanism (WL-WR exchange) of the neutrinoless double beta decay (0nbb-decay), which has origin in left-right symmetric model with right-handed gauge boson at TeV scale, is investigated. The revisited formalism of the 0nbb-decay, which includes higher order terms of nucleon current, is exploited. The corresponding nuclear matrix elements are calculated within quasiparticle random phase approximation with partial restoration of the isospin symmetry for nuclei of experimental interest. A possibility to distinguish between the conventional light neutrino mass (WL-WL exchange) and lambda mechanisms by observation of the 0nbb-decay in several nuclei is discussed. A qualitative comparison of effective lepton number violating couplings associated with these two mechanisms is performed. By making viable assumption about the seesaw type mixing of light and heavy neutrinos it is concluded that there is a dominance of the conventional light neutrino mass mechanism in the decay rate.
Convergent mechanisms favor fast amyloid formation in two lambda 6a Ig light chain mutants.

PubMed

Valdés-García, Gilberto; Millán-Pacheco, César; Pastor, Nina

2017-08-01

Extracellular deposition as amyloids of immunoglobulin light chains causes light chain amyloidosis. Among the light chain families, lambda 6a is one of the most frequent in light chain amyloidosis patients. Its germline protein, 6aJL2, and point mutants, R24G and P7S, are good models to study fibrillogenesis, because their stability and fibril formation characteristics have been described. Both mutations make the germline protein unstable and speed up its ability to aggregate. To date, there is no molecular mechanism that explains how these differences in amyloidogenesis can arise from a single mutation. To look into the structural and dynamical differences in the native state of these proteins, we carried out molecular dynamics simulations at room temperature. Despite the structural similarity of the germline protein and the mutants, we found differences in their dynamical signatures that explain the mutants' increased tendency to form amyloids. The contact network alterations caused by the mutations, though different, converge in affecting two anti-aggregation motifs present in light chain variable domains, suggesting a different starting point for aggregation in lambda chains compared to kappa chains. © 2017 Wiley Periodicals, Inc.
Serum levels of immunoglobulin free light chains in patients with chronic hepatitis C presenting cryoglobulinemia.

PubMed

Oliveira, Isabela S; Cabral, Milena S; Jesus, Larissa S; Paraná, Raymundo; Atta, Ajax M; Sousa Atta, Maria Luiza B

2014-01-01

Hepatitis C virus (HCV) infects B-lymphocytes, provokes cellular dysfunction and causes lymphoproliferative diseases such as cryoglobulinemia and non-Hodgkin's B-cell lymphoma. In the present study, we investigated the serum levels of kappa and lambda free light chains (FLC) of immunoglobulins and the kappa/lambda FLC ratio in Brazilian patients with chronic HCV infection and cryoglobulinemia. We also analyzed the immunochemical composition of the cryoglobulins in these patients. Twenty-eight cryoglobulinemic HCV patients composed the target group, while 37 HCV patients without cryoglobulinemia were included as controls. The median levels of kappa and lambda FLC were higher in patients with cryoglobulinemia compared to controls (p=0.001 and p=0.003, respectively), but the kappa/lambda FLC ratio was similar in patients with and without cryoglobulinemia (p>0.05). The median FLC ratio was higher in HCV patients presenting with advanced fibrosis of the liver compared to HCV patients without fibrosis (p=0.004). Kappa and lambda FLC levels were strongly correlated with the IgA, IgG and IgM levels in the patients with cryoglobulinemia. In patients without cryoglobulinemia, the kappa FLC level was only correlated with the IgG level, whereas the lambda FLC were weakly correlated with the IgA, IgG and IgM levels. An immunochemical pattern of mixed cryoglobulins (MC), predominantly IgM, IgG, IgA and kappa light chain, was verified in these immune complexes. We concluded that HCV-infected patients presenting cryoglobulinemia have vigorous polyclonal B-lymphocyte activation due to chronic HCV infection and persistent immune stimulation. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.
Half molecular exchange of IgGs in the blood of healthy humans: chimeric lambda-kappa-immunoglobulins containing HL fragments of antibodies of different subclasses (IgG1-IgG4).

PubMed

Sedykh, Sergey E; Lekchnov, Evgenii A; Prince, Viktor V; Buneva, Valentina N; Nevinsky, Georgy A

2016-10-20

In the classic paradigm, immunoglobulins represent products of clonal B cell populations, each producing antibodies recognizing a single antigen (monospecific). There is a common belief that IgGs in mammalian biological fluids are monospecific molecules having stable structures and two identical antigen-binding sites. But the issue concerning the possibility of exchange by HL-fragments between the antibody molecules in human blood is still unexplored. Different physico-chemical and immunological methods for analysis of half-molecule exchange between human blood IgGs were used. Using eighteen blood samples of healthy humans we have shown unexpected results for the first time: blood antibodies undergo extensive post-transcriptional half-molecule exchange and IgG pools on average consist of 62.4 ± 6.5% IgGs containing kappa light chains (kappa-kappa-IgGs), 29.8.6 ± 5.4% lambda light chains (lambda-lambda-IgGs), and 8.8 ± 2.7% (range 2.6-16.8%) IgGs containing both kappa- and lambda-light chains. Kappa-kappa-IgGs and lambda-lambda-IgGs contained on average (%): IgG1 (36.0 and 32.3), IgG2 (50.9 and 51.4), IgG3 (9.7 and 9.9), and IgG4 (6.5 and 5.7), while chimeric kappa-lambda-IgGs consisted of (%): 25.5 ± 4.2 IgG1, 50.8 ± 3.9 IgG2, 9.1 ± 2.1 IgG3, and 14.5 ± 2.2 IgG4. Our unexpected data are indicative of the possibility of half-molecule exchange between blood IgGs of various subclasses, raised against different antigens. The existence of blood chimeric bifunctional IgGs with different binding sites destroys the classic paradigm. Due to the phenomenon of polyspecificity and cross-reactivity of bifunctional IgGs containing HL-fragments of different types to different antigens, such IgGs may be important in human blood for widening their different biological functions.
Convex Accelerated Maximum Entropy Reconstruction

PubMed Central

Worley, Bradley

2016-01-01

Maximum entropy (MaxEnt) spectral reconstruction methods provide a powerful framework for spectral estimation of nonuniformly sampled datasets. Many methods exist within this framework, usually defined based on the magnitude of a Lagrange multiplier in the MaxEnt objective function. An algorithm is presented here that utilizes accelerated first-order convex optimization techniques to rapidly and reliably reconstruct nonuniformly sampled NMR datasets using the principle of maximum entropy. This algorithm – called CAMERA for Convex Accelerated Maximum Entropy Reconstruction Algorithm – is a new approach to spectral reconstruction that exhibits fast, tunable convergence in both constant-aim and constant-lambda modes. A high-performance, open source NMR data processing tool is described that implements CAMERA, and brief comparisons to existing reconstruction methods are made on several example spectra. PMID:26894476
Broadband Direct Detection Submillimeter Spectrometer with Multiplexed Superconducting Transition Edge Thermometer Bolometers

NASA Technical Reports Server (NTRS)

Benford, D. J.; Ames, T. A.; Chervenak, J. A.; Moseley, S. H.; Shafer, R. A.; Staguhn, J. G.; Voellmer, G. M.; Pajot, F.; Rioux, C.; Phillips, T. G.;

2002-01-01

We present performance results based on the first astronomical use of multiplexed superconducting bolometers as direct detectors (i.e., with cold electrons) for spectroscopy. The Fabry-Perot Interferometer Bolometer Research Experiment (FIBRE) is a broadband submillimeter spectrometer for the Caltech Submillimeter Observatory (CSO). FIBRE's detectors are superconducting transition edge sensor (TES) bolometers read out by a SQUID multiplexer. The Fabry-Perot uses a low resolution grating to order sort the incoming light. A linear bolometer array consisting of 16 elements detects this dispersed light, capturing 5 orders simultaneously from one position on the sky. With tuning of the Fabry-Perot over one free spectral range, a spectrum covering Delta lambda/lambda = 1/7 at a resolution of delta lambda/lambda = 1/1200 can be acquired. This spectral resolution is sufficient to resolve Doppler-broadened line emission from external galaxies. FIBRE has been operated in the 350 Am (850 GHz) band. These bands cover line emission from the important star formation tracers neutral carbon [CI] and carbon monoxide (CO).

Comparative studies on the conformational change and aggregation behavior of irradiated carrageenans and agar by dynamic light scattering.

PubMed

Abad, Lucille; Okabe, Satoshi; Shibayama, Mitsuhiro; Kudo, Hisaaki; Saiki, Seiichi; Aranilla, Charito; Relleve, Lorna; de la Rosa, Alumanda

2008-01-01

The conformational associative properties of kappa-, iota-, and lambda-carrageenan and agar with irradiation dose were studied by dynamic light scattering. The random scission of the carrageenans and agar by gamma irradiation resulted in the formation of polydispersed lower molecular weight fragments. At high doses, the system moves towards uniformity. Conformational change from coil to helix was observed in all carrageenans and agar at doses up to 100 kGy. The conformational change in lambda-carrageenan may be due to the irregular and hybrid structure of this polysaccharide. Only agar and lambda-carrageenan still undergo conformational transition at a high dose of 200 kGy. Gelation is observed for kappa-, iota-carrageenan up to a dose of 50 kGy while gelation is still observed at 100 kGy for agar. Increase in the hydrodynamic radius with decreasing temperatures for the non-irradiated carrageenans follows this order: lambda-carrageenan>kappa-carrageenan>iota-carrageenan. Slight increases in hydrodynamic radius were observed with irradiation.
Determination of $${{\\rm{\\Lambda }}}_{\\overline{{\\rm{MS}}}}$$ at five loops from holographic QCD

DOE PAGES

Deur, Alexandre; Brodsky, Stanley J.; de Téramond, Guy F.

2017-08-25

Here, the recent determination of themore » $$\\beta$$--function of the QCD running coupling $$\\alpha_{\\overline{MS}}(Q^2)$$ to five-loops, provides a verification of the convergence of a novel method for determining the fundamental QCD parameter $$\\Lambda_s$$ based on the Light-Front Holographic approach to nonperturbative QCD. The new 5-loop analysis, together with improvements in determining the holographic QCD nonperturbative scale parameter $$\\kappa$$ from hadronic spectroscopy, leads to an improved precision of the value of $$\\Lambda_s$$ in the $${\\overline{MS}}$$ scheme close to a factor of two; we find $$\\Lambda^{(3)}_{\\overline{MS}}=0.339\\pm0.019$$ GeV for $$n_{f}=3$$, in excellent agreement with the world average, $$\\Lambda_{\\overline{MS}}^{(3)}=0.332\\pm0.017$$ GeV. Lastly, we also discuss the constraints imposed on the scale dependence of the strong coupling in the nonperturbative domain by superconformal quantum mechanics and its holographic embedding in anti-de Sitter space.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)

Deur, Alexandre; Brodsky, Stanley J.; de Téramond, Guy F.

Here, the recent determination of themore » $$\\beta$$--function of the QCD running coupling $$\\alpha_{\\overline{MS}}(Q^2)$$ to five-loops, provides a verification of the convergence of a novel method for determining the fundamental QCD parameter $$\\Lambda_s$$ based on the Light-Front Holographic approach to nonperturbative QCD. The new 5-loop analysis, together with improvements in determining the holographic QCD nonperturbative scale parameter $$\\kappa$$ from hadronic spectroscopy, leads to an improved precision of the value of $$\\Lambda_s$$ in the $${\\overline{MS}}$$ scheme close to a factor of two; we find $$\\Lambda^{(3)}_{\\overline{MS}}=0.339\\pm0.019$$ GeV for $$n_{f}=3$$, in excellent agreement with the world average, $$\\Lambda_{\\overline{MS}}^{(3)}=0.332\\pm0.017$$ GeV. Lastly, we also discuss the constraints imposed on the scale dependence of the strong coupling in the nonperturbative domain by superconformal quantum mechanics and its holographic embedding in anti-de Sitter space.« less
Measurement of the Lambdab0 lifetime in Lambdab0 --> Lambdac+pi- decays in pp collisions at square root of s = 1.96 TeV.

PubMed

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

2010-03-12

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

PubMed

Armour, K L; Tempest, P R; Fawcett, P H; Fernie, M L; King, S I; White, P; Taylor, G; Harris, W J

1994-12-01

Oligodeoxyribonucleotide primers based on the 5' ends of bovine IgG1/2 and lambda constant (C) region genes, together with primers encoding conserved amino acids at the N-terminus of mature variable (V) regions from other species, have been used in cDNA and polymerase chain reactions (PCRs) to amplify heavy and light chain V region cDNA from bovine heterohybridomas. The amino acid sequences of VH and V lambda from four bovine immunoglobulins of different specificities are presented.
Quantitation of IgG kappa and IgG lambda in the cerebrospinal fluid by sandwich ELISA method.

PubMed

Zeman, David; Kušnierová, Pavlína; Bojková, Jana; Všianský, František; Zapletalová, Olga

2017-01-01

IgG kappa and IgG lambda concentrations were quantified in 96 paired CSF and sera using Hevylite™ antibodies in an in-house developed sandwich ELISA method. In 56 of these samples, the results were compared with a qualitative isoelectric focusing/affinity-mediated immunoblotting assay for oligoclonal IgG kappa and IgG lambda. Normal IgG kappa/lambda ratio in the CSF was the same as in serum. In 19/33 patients with intrathecal oligoclonal IgG synthesis, skewed IgG kappa/lambda ratio was observed (increased in 16 and decreased in 3 cases). The analysis of light chain composition of intrathecally synthesised immunoglobulins could contribute to our understanding of intrathecal humoral immune response, although its diagnostic utility is limited.
Rearrangement and expression of the human {Psi}C{lambda}6 gene segment results in a surface Ig receptor with a truncated light chain constant region

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

Stiernholm, N.B.J.; Verkoczy, L.K.; Berinstein, N.L.

1995-05-01

The constant region of the human Ig{lambda} locus consists of seven tandemly organized J-C gene segments. Although it has been established that the J-C{lambda}1, J-C{lambda}2, J-C{lambda}3, and J-C{lambda}7 gene segments are functional, and code for the four distinct Ig{lambda} isotypes found in human serum, the J-C{lambda}4, J-C{lambda}5, and J-C{lambda}6 gene segments are generally considered to be pseudogenes. Although one example of a functional J-C{lambda}6 gene segment has been documented, in the majority of cases, J-C{lambda}6 is rendered nonfunctional by virtue of a single duplication of four nucleotides, creating a premature translational arrest. We show here that rearrangements to the J-C{lambda}6more » gene segment do occur, and that such a rearrangement encodes an Ig{lambda} protein that lacks the terminal end of the constant region. We also show that this truncated protein is expressed on the surface with the IgH chain, creating an unusual surface Ig (sIg) receptor (sIg{triangle}CL). Cells that express this receptor on the surface do so at significantly reduced levels compared with clonally related variants, which express sIg receptors with conventional Ig{lambda} L chains. However, the effects of sIg cross-linking on tyrosine phosphorylation and surface expression of the CD25 and CD71 Ags are similar in cells that express conventional sIg receptors and in those that express sIg{triangle}CL receptors, suggesting that the latter could possibly function as an Ag receptor. 35 refs., 7 figs.« less
Interferometric apparatus for ultra-high precision displacement measurement

NASA Technical Reports Server (NTRS)

Zhao, Feng (Inventor)

2004-01-01

A high-precision heterodyne interferometer measures relative displacement by creating a thermally-insensitive system generally not subject to polarization leakage. By using first and second light beams separated by a small frequency difference (.DELTA.f), beams of light at the first frequency (f.sub.0) are reflected by co-axial mirrors, the first mirror of which has a central aperture through which the light is transmitted to and reflected by the second mirror. Prior to detection, the light beams from the two mirrors are combined with light of the second and slightly different frequency. The combined light beams are separated according to the light from the mirrors. The change in phase (.DELTA..phi.) with respect to the two signals is proportional to the change in distance of Fiducial B by a factor of wavelength (.lambda.) divided by 4.pi. (.DELTA.L=.lambda..DELTA..phi.1/(4.pi.)). In a second embodiment, a polarizing beam splitting system can be used.
75 FR 57456 - Light-Walled Rectangular Pipe and Tube from the People's Republic of China: Final Results of the...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-21

...'') U.S. affiliated importer FitMAX Inc. (``FitMAX'') on June 2, 2010 and June 16, 2010. FitMAX... carbon- quality light-walled steel pipe and tube, of rectangular (including square) cross section, having...
Microspectrophotometric demonstration of four classes of photoreceptor in an old world primate, Macaca fascicularis.

PubMed Central

Bowmaker, J K; Dartnall, H J; Mollon, J D

1980-01-01

1. Microspectrophotometric measurements reveal four classes of photoreceptor in the retina of the cynomolgus monkey, Macaca fascicularis, which is known to possess colour vision similar to that of a normal human trichromat. 2. Although the eyes were removed in bright illumination, the densities of pigment were comparable to those we have measured in dark-adapted rhesus retinae. 3. The mean wave-lengths of peak sensitivity (lambda max) for the four classes of photoreceptor were 415, 500, 535 and 567 nm. 4. The band widths of the absorbance spectra decreased linearly as the wave-number of peak sensitivity decreased. 5. If, by assuming a reasonable value for the axial density of the rod outer segment and correcting for lens absorption, a spectral sensitivity for human vision is reconstructed from the P500 pigment, it is found to be systematically broader than the CIE scotopic sensitivity function. 6. Given explicit assumptions, it is possible from the P535 and P567 pigments to reconstruct human psychophysical sensitivities that resemble the pi 4 and pi 5 mechanisms of W. S. Stiles. 7. Although the P415 pigment has a lambda max much shorter than that of the psychophysically measured blue mechanisms, the two spectral-sensitivity functions are brought into proximity when the microspectrophotometric data are corrected for absorption by the optic media. Images Fig. 1 PMID:6767023
Simultaneous determination of atorvastatin calcium and olmesartan medoxomil in a pharmaceutical formulation by reversed phase high-performance liquid chromatography, high-performance thin-layer chromatography, and UV spectrophotometric methods.

PubMed

Soni, Hiral; Kothari, Charmy; Khatri, Deepak; Mehta, Priti

2014-01-01

Validated RP-HPLC, HPTLC, and UV spectrophotometric methods have been developed for the simultaneous determination of atorvastatin calcium (ATV) and olmesartan medoxomil (OLM) in a pharmaceutical formulation. The RP-HPLC separation was achieved on a Kromasil C18 column (250 x 4.6 mm, 5 microm particle size) using 0.01 M potassium dihydrogen o-phosphate (pH 4 adjusted with o-phosphoric acid)-acetonitrile (50 + 50, v/v) as the mobile phase at a flow rate of 1.5 mL/min. Quantification was achieved by UV detection at 276 nm. The HPTLC separation was achieved on precoated silica gel 60F254 plates using chloroform-methanol-acetonitrile (4 + 2+ 4, v/v/v) mobile phase. Quantification was achieved with UV detection at 276 nm. The UV-Vis spectrophotometric method was based on the simultaneous equation method that involves measurement of absorbance at two wavelengths, i.e., 255 nm (lambda max of OLM) and 246.2 nm (lambda max of ATV) in methanol. All three methods were validated as per International Conference on Harmonization guidelines. The proposed methods were simple, precise, accurate, and applicable for the simultaneous determination of ATV and OLM in a marketed formulation. The results obtained by applying the proposed methods were statistically analyzed and were found satisfactory.

Determination of trace alkaline phosphatase by solid-substrate room-temperature phosphorimetry based on Triticum vulgare lectin labeled with fullerenol.

PubMed

Liu, Jia-Ming; Gao, Fei; Huang, Hong-Hua; Zeng, Li-Qing; Huang, Xiao-Mei; Zhu, Guo-Hui; Li, Zhi-Ming

2008-04-01

Fullerenol (F) shows a strong and stable room-temperature phosphorescence (RTP) signal on the surface of nitrocellulose membrane (NCM) at lambda ex max/ lambda em max =542.0/709.4 nm. When modified by dodecylbenzenesulfonic acid sodium salt (DBS), fullerenol emits a stronger signal. It was also found that quantitative specific affinity-adsorption reaction can be carried out between Triticum vulgare lectin (WGA) labeled with DBS-F and alkaline phosphatase (ALP) on the surface of NCM, and the product obtained (WGA-ALP-WGA-F-DBS) emits a strong and stable RTP signal. Furthermore, the content of ALP was proportional to the DeltaI(p) value. Based on the facts above, a new method for the determination of trace amounts of ALP by affinity-adsorption solid-substrate room-temperature phosphorimetry (AA-SS-RTP) was established, using fullerenol modified with DBS to label WGA. The detection limit was 0.011 fg spot(-1) (corresponding concentration: 2.8x10(-14) g ml(-1), namely 2.8x10(-16) mol l(-1)). This method with high sensitivity, accuracy, and precision has been successfully applied to the determination of the content of ALP in human serum survey and forecast human disease, and the results are tallied with those using alkaline phosphatase kits. The mechanism for the determination of ALP using AA-SS-RTP was also discussed.
The risk of renal disease is increased in lambda myeloma with bone marrow amyloid deposits.

PubMed

Kozlowski, Piotr; Montgomery, Scott; Befekadu, Rahel; Hahn-Strömberg, Victoria

2017-01-01

Light chain amyloidosis (AL) is a rare deposition disease and is present in 10-15% of patients with myeloma (MM). In contrast to symptomatic AL in MM, presence of bone marrow (BM) amyloid deposits (AD) in MM is not connected to kidney damage. Renal AD but not BM-AD occur mostly in MM with lambda paraprotein (lambda MM). We investigated amyloid presence in BM clots taken at diagnosis in 84 patients with symptomatic MM and compared disease characteristics in MM with kappa paraprotein (kappa MM)/lambda MM with and without BM-AD. Lambda MM with BM-AD was compared with kappa MM without BM-AD, kappa MM with BM-AD, and lambda MM without BM-AD: lambda MM with BM-AD patients had a significantly higher mean creatinine level (4.23 mg/dL vs 1.69, 1.14, and 1.28 mg/dL, respectively) and a higher proportion presented with severe kidney failure (6/11 [55%] vs 6/32 [19%], 1/22 [5%], and 3/19 [16%], respectively). Proteinuria was more common in lambda MM with BM-AD patients compared with kappa MM without BM-AD patients (8/11 [73%] vs 5/32 [16%], respectively). Kidney damage was more common in lambda MM with BM-AD indicating presence of renal AD.
The anomalous C 4 intensity ratio in symbiotic stars

NASA Technical Reports Server (NTRS)

Michalitsianos, A. G.; Kafatos, M.; Fahey, R. P.

1988-01-01

The C IV lambda lambda 1548.2,1550.8 resonance doublet in a symbiotic stars was shown to exhibit anomalous line intensity ratios in which I (lambda 1548.2)/I(lambda 1550.8) less than 1, or less than the optically-thick limit of unity. The R Aquarii-central HII region and RX Puppis exhibit this phenomena. The I(lambda 1548.2)/I(lambda 1550.8) ratio in RX Puppis is found to vary inversely with the total C IV line intensity, and with the FES-visual light, as the object declined over a 5 yr period following a brightening in UV and optical emission which peaked in 1982. This doublet intensity behavior could be explained by a wind which has a narrow velocity range of 600 approx. less than sup v wind approx. less than 1000 km/sec, or by the pumping of the Fe II (mul. 45.01) transition a sup 4 F sub 9/2 - y sup 4 H(o) sub 11/2 by C IV lambda 1548.2, which effectively scatters C IV photons into the Fe II spectrum in these objects.
Absorption of {Lambda}(1520) hyperons in photon-nucleus collisions

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

Paryev, E. Ya.

2012-12-15

In the framework of the nuclear spectral function approach for incoherent primary photon-nucleon and secondary pion-nucleon production processes we study the inclusive {Lambda}(1520)-hyperon production in the interaction of 2-GeV photons with nuclei. In particular, the A and momentum dependences of the absolute and relative {Lambda}(1520)-hyperon yields are investigated in two scenarios for its in-medium width. Our model calculations show that the pion-nucleon production channel contributes appreciably to the {Lambda}(1520) creation at intermediate momenta both in light and heavy nuclei in the chosen kinematics and, hence, has to be taken into consideration on close examination of the dependences of the {Lambda}(1520)-hyperonmore » yields on the target mass number with the aim to get information on its width in the medium. They also demonstrate that the A and momentum dependences of the absolute and relative {Lambda}(1520)-hyperon production cross sections at incident energy of interest are markedly sensitive to the {Lambda}(1520) in-medium width, which means that these observables may be an important tool to determine the above width.« less
System for testing optical fibers

DOEpatents

Davies, Terence J.; Franks, Larry A.; Nelson, Melvin A.

1981-01-01

A system for nondestructively determining the attenuation coefficient, .alpha.(.lambda.), of low-loss optical fiber wave guides. Cerenkov light pulses are generated at a plurality of locations in the fiber by a beam of charged particles. The transit times of selected spectral components and their intensities are utilized to unfold the .alpha.(.lambda.) values over the measured spectrum.
Effects of heat induced by two-photon absorption and free-carrier absorption in silicon-on-insulator nanowaveguides operating as all-optical wavelength converters.

PubMed

Abdollahi, Siamak; Moravvej-Farshi, Mohammad Kazem

2009-05-01

We propose a new numerical model to analyze heat induced by two-photon absorption and free-carrier absorption, while high intensity optical pulses propagate along silicon-on-insulator (SOI) nanowaveguides (NWGs). Using this model, we demonstrate that such induced heat causes a shift in the amount of wavelength conversion and hence deteriorates the converter output characteristics for pulses in the picosecond regime. The wavelength shift induced by a pulse with maximum input intensity and full width at half-maximum of I(max)=1.5x10(10) W x cm(-2) and T(FWHM)=30 ps, propagating along a SOI NWG with an effective cross-sectional area of a(eff)=0.15 microm(2), is shown to be Delta lambda(s) approximately 8 pm. We also demonstrate that such a shift can be compensated by tuning the pump intensity down by approximately 6.33%.
Physical parameters of lambda Bootis stars

NASA Astrophysics Data System (ADS)

Solano, E.; Paunzen, E.; Pintado, O. I.; Córdoba; Varela, J.

2001-08-01

This is the first of two papers whose main goal is to update and improve the information available on the physical properties of the lambda Bootis stars. The determination of the stellar parameters is of fundamental importance to shed light into the different theories proposed to explain the lambda Bootis phenomenon. With this aim, projected rotational velocities, effective temperatures, surface gravities and chemical abundances of a sample of suspected lambda Bootis stars have been calculated. Five objects showing composite spectra typical of binary systems were found in our analysis. The abundance distribution of the program stars does not resemble the chemical composition of the class prototype, lambda Boo, which poses some concerns regarding the idea of a well-defined, chemically homogeneous group of stars. A possible relation between rotational velocities and the lambda Bootis phenomenon has been found. This result would be in agreement with the accretion scenario proposed by Turcotte & Charbonneau (\\cite{Turcotte93}). Figure 3 is only available in electronic form at http://www.edpsciences.org
The impact of firefighter personal protective equipment and treadmill protocol on maximal oxygen uptake.

PubMed

Lee, Joo-Young; Bakri, Ilham; Kim, Jung-Hyun; Son, Su-Young; Tochihara, Yutaka

2013-01-01

This study investigated the effects of firefighter personal protective equipment (PPE) on the determination of maximal oxygen uptake (VO(2max)) while using two different treadmill protocols: a progressive incline protocol (PIP) and a progressive speed protocol (PSP), with three clothing conditions (Light-light clothing; Boots-PPE with rubber boots; Shoes-PPE with running shoes). Bruce protocol with Light was performed for a reference test. Results showed there was no difference in VO(2max) between Bruce Light, PIP Light, and PSP Light. However, VO(2max) was reduced in Boots and Shoes with shortened maximal performance time (7 and 6 min reduced for PIP Boots and Shoes, respectively; 11 and 9 min reduced for PSP Boots and Shoes, respectively), whereas the increasing rate of VO(2) in Boots and Shoes during submaximal exercise was greater compared with Light. Wearing firefighter boots compared with wearing running shoes also significantly affected submaximal VO(2) but not VO(2max). These results suggest that firefighters' maximal performance determined from a typical VO(2max) test without wearing PPE may overestimate the actual performance capability of firefighters wearing PPE.
The Impact of Firefighter Personal Protective Equipment and Treadmill Protocol on Maximal Oxygen Uptake

PubMed Central

Lee, Joo-Young; Bakri, Ilham; Kim, Jung-Hyun; Son, Su-Young; Tochihara, Yutaka

2015-01-01

This study investigated the effects of firefighter personal protective equipment (PPE) on the determination of maximal oxygen uptake (VO2max) while using two different treadmill protocols: a progressive incline protocol (PIP) and a progressive speed protocol (PSP), with three clothing conditions (Light-light clothing; Boots-PPE with rubber boots; Shoes-PPE with running shoes). Bruce protocol with Light was performed for a reference test. Results showed there was no difference in VO2max between Bruce Light, PIP Light, and PSP Light. However, VO2max was reduced in Boots and Shoes with shortened maximal performance time (7 and 6 min reduced for PIP Boots and Shoes, respectively; 11 and 9 min reduced for PSP Boots and Shoes, respectively), whereas the increasing rate of VO2 in Boots and Shoes during submaximal exercise was greater compared with Light. Wearing firefighter boots compared with wearing running shoes also significantly affected submaximal VO2 but not VO2max. These results suggest that firefighters’ maximal performance determined from a typical VO2max test without wearing PPE may overestimate the actual performance capability of firefighters wearing PPE. PMID:23668854
Human placenta: relative content of antibodies of different classes and subclasses (IgG1-IgG4) containing lambda- and kappa-light chains and chimeric lambda-kappa-immunoglobulins.

PubMed

Lekchnov, Evgenii A; Sedykh, Sergey E; Dmitrenok, Pavel S; Buneva, Valentina N; Nevinsky, Georgy A

2015-06-01

The specific organ placenta is much more than a filter: it is an organ that protects, feeds and regulates the growth of the embryo. Affinity chromatography, ELISA, SDS-PAGE and matrix-assisted laser desorption ionization mass spectrometry were used. Using 10 intact human placentas deprived of blood, a quantitative analysis of average relative content [% of total immunoglobulins (Igs)] was carried out for the first time: (92.7), IgA (2.4), IgM (2.5), kappa-antibodies (51.4), lambda-antibodies (48.6), IgG1 (47.0), IgG2 (39.5), IgG3 (8.8) and IgG4 (4.3). It was shown for the first time that placenta contains sIgA (2.5%). In the classic paradigm, Igs represent products of clonal B-cell populations, each producing antibodies recognizing a single antigen. There is a common belief that IgGs in mammalian biological fluids are monovalent molecules having stable structures and two identical antigen-binding sites. However, similarly to human milk Igs, placenta antibodies undergo extensive half-molecule exchange and the IgG pool consists of 43.5 ± 15.0% kappa-kappa-IgGs and 41.6 ± 17.0% lambda-lambda-IgGs, while 15.0 ± 4.0% of the IgGs contained both kappa- and lambda-light chains. Kappa-kappa-IgGs and lambda-lambda-IgGs contained, respectively (%): IgG1 (47.7 and 34.4), IgG2 (36.3 and 44.5), IgG3 (7.4 and 11.8) and IgG4 (7.5 and 9.1), while chimeric kappa-lambda-IgGs consisted of (%): 43.5 IgG1, 41.0 IgG2, 5.6 IgG3 and 7.9 IgG4. Our data are indicative of the possibility of half-molecule exchange between placenta IgGs of various subclasses, raised against different antigens, which explains a very well-known polyspecificity and cross-reactivity of different human IgGs. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Phycourobilin in trichromatic phycocyanin from oceanic cyanobacteria is formed post-translationally by a phycoerythrobilin lyase-isomerase.

PubMed

Blot, Nicolas; Wu, Xian-Jun; Thomas, Jean-Claude; Zhang, Juan; Garczarek, Laurence; Böhm, Stephan; Tu, Jun-Ming; Zhou, Ming; Plöscher, Matthias; Eichacker, Lutz; Partensky, Frédéric; Scheer, Hugo; Zhao, Kai-Hong

2009-04-03

Most cyanobacteria harvest light with large antenna complexes called phycobilisomes. The diversity of their constituting phycobiliproteins contributes to optimize the photosynthetic capacity of these microorganisms. Phycobiliprotein biosynthesis, which involves several post-translational modifications including covalent attachment of the linear tetrapyrrole chromophores (phycobilins) to apoproteins, begins to be well understood. However, the biosynthetic pathway to the blue-green-absorbing phycourobilin (lambda(max) approximately 495 nm) remained unknown, although it is the major phycobilin of cyanobacteria living in oceanic areas where blue light penetrates deeply into the water column. We describe a unique trichromatic phycocyanin, R-PC V, extracted from phycobilisomes of Synechococcus sp. strain WH8102. It is evolutionarily remarkable as the only chromoprotein known so far that absorbs the whole wavelength range between 450 and 650 nm. R-PC V carries a phycourobilin chromophore on its alpha-subunit, and this can be considered an extreme case of adaptation to blue-green light. We also discovered the enzyme, RpcG, responsible for its biosynthesis. This monomeric enzyme catalyzes binding of the green-absorbing phycoerythrobilin at cysteine 84 with concomitant isomerization to phycourobilin. This reaction is analogous to formation of the orange-absorbing phycoviolobilin from the red-absorbing phycocyanobilin that is catalyzed by the lyase-isomerase PecE/F in some freshwater cyanobacteria. The fusion protein, RpcG, and the heterodimeric PecE/F are mutually interchangeable in a heterologous expression system in Escherichia coli. The novel R-PC V likely optimizes rod-core energy transfer in phycobilisomes and thereby adaptation of a major phytoplankton group to the blue-green light prevailing in oceanic waters.
Discharge-pumped cw gas lasers utilizing 'dressed-atom' gain media

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

Sorokin, P.P.; Glownia, J.H.; Hodgson, R.T.

The possibility of realizing an efficient gaseous laser-beam-generating medium that utilizes {lambda}-type coherently phased (i.e., 'dressed') atoms for the active laser species, but that does not inherently require the use of external laser beams for pumping, is explored. Specifically, it is investigated if multiphoton stimulated hyper-Raman scattering (SHRS) processes driven by fluorescence radiation generated in a continuous electrical discharge present within the vapor-containing cell could produce continuous-wave (cw) optical gain at the {lambda}-atom resonance frequencies {omega}{sub o} and {omega}{sub o}{sup '}. It is deduced that such gain could result from n-photon (n{>=}4) SHRS processes only if absorption of fluorescence pumpmore » light occurs in the first three transitions of the n-photon sequence representing the process unit step. Estimates of the amount of optical gain that could be produced in such a system indicate that it should be sufficient to allow multiwatt cw laser operation to occur on one set of {lambda} transitions connecting levels in a 'double-{lambda}' structure, with the pump light being discharge-produced fluorescence centered about the transitions of the other {lambda} pair. However, to initiate operation of such a device would require injection into the laser optical cavity of intense 'starter' laser pulses at both lasing frequencies. What should be an optimal experimental configuration for determining feasibility of the proposed laser device is described. In the suggested configuration, Cs-atom 6S{sub 1/2}-6P{sub 1/2} transitions form the double-{lambda} structure.« less
Study of light transmission through gauze pad effected by blood or liquids to detect needle dislodgement.

PubMed

Takeuchi, Akihiro; Ishida, Kai; Morohoshi, Yasuo; Shinbo, Toshihiro; Hirose, Minoru; Ikeda, Noriaki

2010-02-01

Serious accidents during hemodialysis such as a large amount of blood loss are often caused by venous needle dislodgement. To develop a bleeding sensor based on a photo sensor for monitoring the needle sites, we studied effects of liquids and porcine blood on light transmission through a thin gauze pad with a basic photo sensor. The photo sensor consisted of an ordinary electrical circuit, a light emitting diode (LED, lambda max = 645 nm), a photo diode (PD), and a thin gauze pad placed between the LED and PD that were tightly attached to the edges of a plastic clip. The light transmitted through the gauze pad, soaked with liquids or porcine blood dropped on it, was measured with a digital voltmeter. The liquids were reverse osmosis water, physiological saline, glucose in water at 5, 10, 20, 40 and 50%, porcine plasma, and porcine blood (Hct 40, 30 and 20%). The liquids on a tight-weave gauze pad, significantly increased the voltage (light transmission) from 0.412 +/- 0.003 V (SD) to 0.794 +/- 0.025 V (minimum, by reverse osmosis water) and to 0.945 +/- 0.011 V (maximum, by 50% glucose). The porcine blood significantly decreased the voltage from 0.412 to 0.195 +/- 0.030 V in Hct 40%, to 0.334 +/- 0.035 in Hct 30%, to 0.397 +/- 0.007 V in Hct 20%. The higher the concentration of glucose, the more the light transmission increased. The higher concentration of Hct, the more the light transmission decreased. Similar results were also shown for the loose-weave pad. Using two types of gauze pads, we confirmed that liquids significantly increased light transmission through gauze pad, but porcine blood decreased light transmission. This opposite response can be used to distinguish liquids from blood on a gauze pad.
Chlorophyll fluorescence and CO(2) assimilation of black spruce seedlings following frost in different temperature and light conditions.

PubMed

Lamontagne, M.; Bigras, F. J.; Margolis, H. A.

2000-03-01

Effects of artificial frosts on light-saturated photosynthesis (A(max)) and ground, maximal and variable fluorescence variables (F(o), F(m), and F(v) and F(v)/F(m)) were monitored on 1-year-old foliage of black spruce seedlings (Picea mariana (Mill.) BSP) grown at high (25 degrees C), moderate (15 degrees C) and low (5 degrees C) temperatures and moderate (240 &mgr;mol m(-2) s(-1)) and low (80 &mgr;mol m(-2) s(-1)) irradiances. Photoinhibition of 1-year-old foliage was greater in seedlings grown in moderate light than in seedlings grown in low light. Photoinhibition increased with decreasing growth chamber temperature at both irradiances. Most changes in F(v)/F(m) were caused by changes in F(v). Exposure to -4 degrees C decreased both F(v)/F(m) and A(max) compared with control values. The effect of the -4 degrees C frost treatment was greater in seedlings grown in low light than in seedlings grown in moderate light, probably because seedlings grown in moderate light were already partially photoinhibited before the frost treatment. Following -4 degrees C treatment, neither F(v)/F(m) nor A(max) recovered in seedlings grown in low light. Light-saturated photosynthesis decreased with decreasing growth chamber temperature. Light-saturated photosynthesis was more sensitive to the -3 and -4 degrees C frost treatments in seedlings grown at 25 degrees C than in seedlings grown at 15 and 5 degrees C. The A(max) of seedlings grown at 15 degrees C was sensitive only to the -4 degrees C frost treatment, whereas A(max) of seedlings grown at 5 degrees C was not sensitive to any of the frost treatments. Recovery of A(max) following frost took longer in seedlings grown at high temperatures than in seedlings grown at low temperatures. For seedlings grown at the same temperature but under different irradiances, both A(max) and F(v)/F(m) reflected damage to the photosynthetic system following a moderate frost. However, for seedlings grown at the same irradiance but different temperatures, A(max) provided a more sensitive indicator of frost damage to the photosynthetic system than F(v)/F(m) ratio.
Estimation of soft X-ray and EUV transition radiation power emitted from the MIRRORCLE-type tabletop synchrotron.

PubMed

Toyosugi, N; Yamada, H; Minkov, D; Morita, M; Yamaguchi, T; Imai, S

2007-03-01

The tabletop synchrotron light sources MIRRORCLE-6X and MIRRORCLE-20SX, operating at electron energies E(el) = 6 MeV and E(el) = 20 MeV, respectively, can emit powerful transition radiation (TR) in the extreme ultraviolet (EUV) and the soft X-ray regions. To clarify the applicability of these soft X-ray and EUV sources, the total TR power has been determined. A TR experiment was performed using a 385 nm-thick Al foil target in MIRRORCLE-6X. The angular distribution of the emitted power was measured using a detector assembly based on an NE102 scintillator, an optical bundle and a photomultiplier. The maximal measured total TR power for MIRRORCLE-6X is P(max) approximately equal 2.95 mW at full power operation. Introduction of an analytical expression for the lifetime of the electron beam allows calculation of the emitted TR power by a tabletop synchrotron light source. Using the above measurement result, and the theoretically determined ratio between the TR power for MIRRORCLE-6X and MIRRORCLE-20SX, the total TR power for MIRRORCLE-20SX can be obtained. The one-foil TR target thickness is optimized for the 20 MeV electron energy. P(max) approximately equal 810 mW for MIRRORCLE-20SX is obtained with a single foil of 240 nm-thick Be target. The emitted bremsstrahlung is negligible with respect to the emitted TR for optimized TR targets. From a theoretically known TR spectrum it is concluded that MIRRORCLE-20SX can emit 150 mW of photons with E > 500 eV, which makes it applicable as a source for performing X-ray lithography. The average wavelength, \\overline\\lambda = 13.6 nm, of the TR emission of MIRRORCLE-20SX, with a 200 nm Al target, could provide of the order of 1 W EUV.
Organic light-emitting diodes from homoleptic square planar complexes

DOEpatents

Omary, Mohammad A

2013-11-12

Homoleptic square planar complexes [M(N.LAMBDA.N).sub.2], wherein two identical N.LAMBDA.N bidentate anionic ligands are coordinated to the M(II) metal center, including bidentate square planar complexes of triazolates, possess optical and electrical properties that make them useful for a wide variety of optical and electrical devices and applications. In particular, the complexes are useful for obtaining white or monochromatic organic light-emitting diodes ("OLEDs"). Improved white organic light emitting diode ("WOLED") designs have improved efficacy and/or color stability at high brightness in single- or two-emitter white or monochrome OLEDs that utilize homoleptic square planar complexes, including bis[3,5-bis(2-pyridyl)-1,2,4-triazolato]platinum(II) ("Pt(ptp).sub.2").
Trends in leaf photosynthesis in historical rice varieties developed in the Philippines since 1966.

PubMed

Hubbart, S; Peng, S; Horton, P; Chen, Y; Murchie, E H

2007-01-01

Crop improvement in terms of yield is rarely linked to leaf photosynthesis. However, in certain crop plants such as rice, it is predicted that an increase in photosynthetic rate will be required to support future grain yield potential. In order to understand the relationships between yield improvement and leaf photosynthesis, controlled environment conditions were used to grow 10 varieties which were released from the International Rice Research Institute (IRRI) between 1966 and 1995 and one newly developed line. Two growth light intensities were used: high light (1500 micromol m(-2) s(-1)) and low light (300 micromol m(-2) s(-1)). Gas exchange, leaf protein, chlorophyll, and leaf morphology were measured in the ninth leaf on the main stem. A high level of variation was observed among high light-grown plants for light-saturated photosynthetic rate per unit leaf area (P(max)), stomatal conductance (g), content of ribulose bisphosphate carboxylase-oxygenase (Rubisco), and total leaf protein content. Notably, between 1966 and 1980 there was a decline in P(max), g, leaf protein, chlorophyll, and Rubisco content. Values recovered in those varieties released after 1980. This striking trend coincides with a previous published observation that grain yield in IRRI varieties released prior to 1980 correlated with harvest index whereas that for those released after 1980 correlated with biomass. P(max) showed significant correlations with both g and Rubisco content. Large differences were observed between high light- and low light-grown plants (photoacclimation). The photoacclimation 'range' for P(max) correlated with P(max) in high light-grown plants. It is concluded that (i) leaf photosynthesis may be systematically affected by breeding strategy; (ii) P(max) is a useful target for yield improvements where yield is limited by biomass production rather than partitioning; and (iii) the capacity for photoacclimation is related to high P(max) values.
Observation of an antimatter hypernucleus.

PubMed

Abelev, B I; Aggarwal, M M; Ahammed, Z; Alakhverdyants, A V; Alekseev, I; Anderson, B D; Arkhipkin, D; Averichev, G S; Balewski, J; Barnby, L S; Baumgart, S; Beavis, D R; Bellwied, R; Betancourt, M J; Betts, R R; Bhasin, A; Bhati, A K; Bichsel, H; Bielcik, J; Bielcikova, J; Biritz, B; Bland, L C; Bonner, B E; Bouchet, J; Braidot, E; Brandin, A V; Bridgeman, A; Bruna, E; Bueltmann, S; Bunzarov, I; Burton, T P; Cai, X Z; Caines, H; Calderon, M; Catu, O; Cebra, D; Cendejas, R; Cervantes, M C; Chajecki, Z; Chaloupka, P; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, J Y; Cheng, J; Cherney, M; Chikanian, A; Choi, K E; Christie, W; Chung, P; Clarke, R F; Codrington, M J M; Corliss, R; Cramer, J G; Crawford, H J; Das, D; Dash, S; Davila Leyva, A; De Silva, L C; Debbe, R R; Dedovich, T G; DePhillips, M; Derevschikov, A A; Derradi de Souza, R; Didenko, L; Djawotho, P; Dogra, S M; Dong, X; Drachenberg, J L; Draper, J E; Dunlop, J C; Dutta Mazumdar, M R; Efimov, L G; Elhalhuli, E; Elnimr, M; Engelage, J; Eppley, G; Erazmus, B; Estienne, M; Eun, L; Evdokimov, O; Fachini, P; Fatemi, R; Fedorisin, J; Fersch, R G; Filip, P; Finch, E; Fine, V; Fisyak, Y; Gagliardi, C A; Gangadharan, D R; Ganti, M S; Garcia-Solis, E J; Geromitsos, A; Geurts, F; Ghazikhanian, V; Ghosh, P; Gorbunov, Y N; Gordon, A; Grebenyuk, O; Grosnick, D; Grube, B; Guertin, S M; Gupta, A; Gupta, N; Guryn, W; Haag, B; Hamed, A; Han, L-X; Harris, J W; Hays-Wehle, J P; Heinz, M; Heppelmann, S; Hirsch, A; Hjort, E; Hoffman, A M; Hoffmann, G W; Hofman, D J; Hollis, R S; Huang, B; Huang, H Z; Humanic, T J; Huo, L; Igo, G; Iordanova, A; Jacobs, P; Jacobs, W W; Jakl, P; Jena, C; Jin, F; Jones, C L; Jones, P G; Joseph, J; Judd, E G; Kabana, S; Kajimoto, K; Kang, K; Kapitan, J; Kauder, K; Keane, D; Kechechyan, A; Kettler, D; Kikola, D P; Kiryluk, J; Kisiel, A; Klein, S R; Knospe, A G; Kocoloski, A; Koetke, D D; Kollegger, T; Konzer, J; Kopytine, M; Koralt, I; Koroleva, L; Korsch, W; Kotchenda, L; Kouchpil, V; Kravtsov, P; Krueger, K; Krus, M; Kumar, L; Kurnadi, P; Lamont, M A C; Landgraf, J M; LaPointe, S; Lauret, J; Lebedev, A; Lednicky, R; Lee, C-H; Lee, J H; Leight, W; Levine, M J; Li, C; Li, L; Li, N; Li, W; Li, X; Li, Y; Li, Z; Lin, G; Lindenbaum, S J; Lisa, M A; Liu, F; Liu, H; Liu, J; Ljubicic, T; Llope, W J; Longacre, R S; Love, W A; Lu, Y; Luo, X; Ma, G L; Ma, Y G; Mahapatra, D P; Majka, R; Mal, O I; Mangotra, L K; Manweiler, R; Margetis, S; Markert, C; Masui, H; Matis, H S; Matulenko, Yu A; McDonald, D; McShane, T S; Meschanin, A; Milner, R; Minaev, N G; Mioduszewski, S; Mischke, A; Mitrovski, M K; Mohanty, B; Mondal, M M; Morozov, B; Morozov, D A; Munhoz, M G; Nandi, B K; Nattrass, C; Nayak, T K; Nelson, J M; Netrakanti, P K; Ng, M J; Nogach, L V; Nurushev, S B; Odyniec, G; Ogawa, A; Okada, H; Okorokov, V; Olson, D; Pachr, M; Page, B S; Pal, S K; Pandit, Y; Panebratsev, Y; Pawlak, T; Peitzmann, T; Perevoztchikov, V; Perkins, C; Peryt, W; Phatak, S C; Pile, P; Planinic, M; Ploskon, M A; Pluta, J; Plyku, D; Poljak, N; Poskanzer, A M; Potukuchi, B V K S; Powell, C B; Prindle, D; Pruneau, C; Pruthi, N K; Pujahari, P R; Putschke, J; Qiu, H; Raniwala, R; Raniwala, S; Ray, R L; Redwine, R; Reed, R; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Rose, A; Roy, C; Ruan, L; Sahoo, R; Sakai, S; Sakrejda, I; Sakuma, T; Salur, S; Sandweiss, J; Sangaline, E; Schambach, J; Scharenberg, R P; Schmitz, N; Schuster, T R; Seele, J; Seger, J; Selyuzhenkov, I; Seyboth, P; Shahaliev, E; Shao, M; Sharma, M; Shi, S S; Sichtermann, E P; Simon, F; Singaraju, R N; Skoby, M J; Smirnov, N; Sorensen, P; Sowinski, J; Spinka, H M; Srivastava, B; Stanislaus, T D S; Staszak, D; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Suaide, A A P; Suarez, M C; Subba, N L; Sumbera, M; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szanto de Toledo, A; Takahashi, J; Tang, A H; Tang, Z; Tarini, L H; Tarnowsky, T; Thein, D; Thomas, J H; Tian, J; Timmins, A R; Timoshenko, S; Tlusty, D; Tokarev, M; Trainor, T A; Tram, V N; Trentalange, S; Tribble, R E; Tsai, O D; Ulery, J; Ullrich, T; Underwood, D G; Van Buren, G; van Leeuwen, M; van Nieuwenhuizen, G; Vanfossen, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Videbaek, F; Viyogi, Y P; Vokal, S; Voloshin, S A; Wada, M; Walker, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, Q; Wang, X L; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Whitten, C; Wieman, H; Wingfield, E; Wissink, S W; Witt, R; Wu, Y; Xie, W; Xu, H; Xu, N; Xu, Q H; Xu, W; Xu, Y; Xu, Z; Xue, L; Yang, Y; Yepes, P; Yip, K; Yoo, I-K; Yue, Q; Zawisza, M; Zbroszczyk, H; Zhan, W; Zhang, J; Zhang, S; Zhang, W M; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, J; Zhong, C; Zhou, J; Zhou, W; Zhu, X; Zhu, Y H; Zoulkarneev, R; Zoulkarneeva, Y

2010-04-02

Nuclear collisions recreate conditions in the universe microseconds after the Big Bang. Only a very small fraction of the emitted fragments are light nuclei, but these states are of fundamental interest. We report the observation of antihypertritons--comprising an antiproton, an antineutron, and an antilambda hyperon--produced by colliding gold nuclei at high energy. Our analysis yields 70 +/- 17 antihypertritons ((Lambda)(3)-H) and 157 +/- 30 hypertritons (Lambda3H). The measured yields of Lambda3H ((Lambda)(3)-H) and 3He (3He) are similar, suggesting an equilibrium in coordinate and momentum space populations of up, down, and strange quarks and antiquarks, unlike the pattern observed at lower collision energies. The production and properties of antinuclei, and of nuclei containing strange quarks, have implications spanning nuclear and particle physics, astrophysics, and cosmology.
The protein interaction map of bacteriophage lambda

PubMed Central

2011-01-01

Background Bacteriophage lambda is a model phage for most other dsDNA phages and has been studied for over 60 years. Although it is probably the best-characterized phage there are still about 20 poorly understood open reading frames in its 48-kb genome. For a complete understanding we need to know all interactions among its proteins. We have manually curated the lambda literature and compiled a total of 33 interactions that have been found among lambda proteins. We set out to find out how many protein-protein interactions remain to be found in this phage. Results In order to map lambda's interactions, we have cloned 68 out of 73 lambda open reading frames (the "ORFeome") into Gateway vectors and systematically tested all proteins for interactions using exhaustive array-based yeast two-hybrid screens. These screens identified 97 interactions. We found 16 out of 30 previously published interactions (53%). We have also found at least 18 new plausible interactions among functionally related proteins. All previously found and new interactions are combined into structural and network models of phage lambda. Conclusions Phage lambda serves as a benchmark for future studies of protein interactions among phage, viruses in general, or large protein assemblies. We conclude that we could not find all the known interactions because they require chaperones, post-translational modifications, or multiple proteins for their interactions. The lambda protein network connects 12 proteins of unknown function with well characterized proteins, which should shed light on the functional associations of these uncharacterized proteins. PMID:21943085
Self-organized coherent bursts of stimulated Raman scattering and speckle interaction in multi-speckled laser beams

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

Yin, L.; Albright, B. J.; Rose, H. A.

2013-01-15

Nonlinear physics governing the kinetic behavior of stimulated Raman scattering (SRS) in multi-speckled laser beams has been identified in the trapping regime over a wide range of k{lambda}{sub D} values (here k is the wave number of the electron plasma waves and {lambda}{sub D} is the Debye length) in homogeneous and inhomogeneous plasmas. Hot electrons from intense speckles, both forward and side-loss hot electrons produced during SRS daughter electron plasma wave bowing and filamentation, seed and enhance the growth of SRS in neighboring speckles by reducing Landau damping. Trapping-enhanced speckle interaction through transport of hot electrons, backscatter, and sidescatter SRSmore » light waves enable the system of speckles to self-organize and exhibit coherent, sub-ps SRS bursts with more than 100% instantaneous reflectivity, resulting in an SRS transverse coherence width much larger than a speckle width and a SRS spectrum that peaks outside the incident laser cone. SRS reflectivity is found to saturate above a threshold laser intensity at a level of reflectivity that depends on k{lambda}{sub D}: higher k{lambda}{sub D} leads to lower SRS and the reflectivity scales as {approx}(k{lambda}{sub D}){sup -4}. As k{lambda}{sub D} and Landau damping increase, speckle interaction via sidescattered light and side-loss hot electrons decreases and the occurrence of self-organized events becomes infrequent, leading to the reduction of time-averaged SRS reflectivity. It is found that the inclusion of a moderately strong magnetic field in the laser direction can effectively control SRS by suppressing transverse speckle interaction via hot electron transport.« less

Diffractive centrosymmetric 3D-transmission phase gratings positioned at the image plane of optical systems transform lightlike 4D-WORLD as tunable resonators into spectral metrics...

NASA Astrophysics Data System (ADS)

Lauinger, Norbert

1999-08-01

Diffractive 3D phase gratings of spherical scatterers dense in hexagonal packing geometry represent adaptively tunable 4D-spatiotemporal filters with trichromatic resonance in visible spectrum. They are described in the (lambda) - chromatic and the reciprocal (nu) -aspects by reciprocal geometric translations of the lightlike Pythagoras theorem, and by the direction cosine for double cones. The most elementary resonance condition in the lightlike Pythagoras theorem is given by the transformation of the grating constants gx, gy, gz of the hexagonal 3D grating to (lambda) h1h2h3 equals (lambda) 111 with cos (alpha) equals 0.5. Through normalization of the chromaticity in the von Laue-interferences to (lambda) 111, the (nu) (lambda) equals (lambda) h1h2h3/(lambda) 111-factor of phase velocity becomes the crucial resonance factor, the 'regulating device' of the spatiotemporal interaction between 3D grating and light, space and time. In the reciprocal space equal/unequal weights and times in spectral metrics result at positions of interference maxima defined by hyperbolas and circles. A database becomes built up by optical interference for trichromatic image preprocessing, motion detection in vector space, multiple range data analysis, patchwide multiple correlations in the spatial frequency spectrum, etc.
Recent developments in Lambda networking

NASA Astrophysics Data System (ADS)

de Laat, C.; Grosso, P.

About 6 years ago the first baby-steps were made on opening up dark fiber and DWDM infrastructure for direct use by ISP's after the transformation of the old style Telecom sector into a market driven business. Since then Lambda workshops, community groups like GLIF and a number of experiments have led to many implementations of hybrid national research and education networks and lightpath-based circuit exchanges as pioneered by SURFnet in GigaPort and NetherLight in collaboration with StarLight in Chicago and Canarie in Canada. This article looks back on those developments, describes some current open issues and research developments and proposes a concept of terabit networking.
Phase shifting diffraction interferometer

DOEpatents

Sommargren, Gary E.

1996-01-01

An interferometer which has the capability of measuring optical elements and systems with an accuracy of .lambda./1000 where .lambda. is the wavelength of visible light. Whereas current interferometers employ a reference surface, which inherently limits the accuracy of the measurement to about .lambda./50, this interferometer uses an essentially perfect spherical reference wavefront generated by the fundamental process of diffraction. This interferometer is adjustable to give unity fringe visibility, which maximizes the signal-to-noise, and has the means to introduce a controlled prescribed relative phase shift between the reference wavefront and the wavefront from the optics under test, which permits analysis of the interference fringe pattern using standard phase extraction algorithms.
Phase shifting diffraction interferometer

DOEpatents

Sommargren, G.E.

1996-08-29

An interferometer which has the capability of measuring optical elements and systems with an accuracy of {lambda}/1000 where {lambda} is the wavelength of visible light. Whereas current interferometers employ a reference surface, which inherently limits the accuracy of the measurement to about {lambda}/50, this interferometer uses an essentially perfect spherical reference wavefront generated by the fundamental process of diffraction. This interferometer is adjustable to give unity fringe visibility, which maximizes the signal-to-noise, and has the means to introduce a controlled prescribed relative phase shift between the reference wavefront and the wavefront from the optics under test, which permits analysis of the interference fringe pattern using standard phase extraction algorithms. 8 figs.
The membrane current of single rod outer segments.

PubMed

Baylor, D A; Lamb, T D; Yau, K W

1979-03-01

1. Outer segments of individual rods in the retina of the toad, Bufo marinus, were drawn into a glass pipette to record the membrane current. 2. Light flashes evoked transient outward currents. The peak response amplitude was related to flash intensity by a Michaelis equation with half-saturating intensity about 1 photon mum-2. 3. The saturating response amplitude ranged up to 27 pA and corresponded closely to complete suppression of the steady inward current present in darkness. 4. For a given cell the saturating response amplitude varied linearly with the length of outer segment within the pipette. This is consistent with a uniform density of light-sensitive channels and negligible gradient of membrane potential along the outer segment. 5. Responses to bright flashes never showed the relaxation from an initial peak seen previously in intracellular voltage recordings, suggesting that the conductance change responsible for the relaxation does not occur in the outer segment. 6. Responses to local illumination of only the recorded outer segment were very similar to those obtained with diffuse light at the same intensity, indicating that peripheral rods made little contribution to the responses. 7. The spectral sensitivity of 'red' rods was consistent with a retinal1-based pigment with lambda max = 498 +/- 2 nm. 8. The kinetics of the response were consistent with four stages of delay affecting action of the internal transmitter. Responses were faster at the basal end of the outer segment than at the distal tip. 9. Background light reduced the sensitivity to a superposed dim test flash and shortened the time course of the response, indicating that adapting light modifies the kinetics and gain of the transduction mechanism within the outer segment. 10. Responses to dim lights exhibited pronounced fluctuations which are attributed in the succeeding paper (Baylor, Lamb & Yau, 1979) to the quantal nature of light.
Strength functions, entropies, and duality in weakly to strongly interacting fermionic systems.

PubMed

Angom, D; Ghosh, S; Kota, V K B

2004-01-01

We revisit statistical wave function properties of finite systems of interacting fermions in the light of strength functions and their participation ratio and information entropy. For weakly interacting fermions in a mean-field with random two-body interactions of increasing strength lambda, the strength functions F(k) (E) are well known to change, in the regime where level fluctuations follow Wigner's surmise, from Breit-Wigner to Gaussian form. We propose an ansatz for the function describing this transition which we use to investigate the participation ratio xi(2) and the information entropy S(info) during this crossover, thereby extending the known behavior valid in the Gaussian domain into much of the Breit-Wigner domain. Our method also allows us to derive the scaling law lambda(d) approximately 1/sqrt[m] ( m is number of fermions) for the duality point lambda= lambda(d), where F(k) (E), xi(2), and S(info) in both the weak ( lambda=0 ) and strong mixing ( lambda= infinity ) basis coincide. As an application, the ansatz function for strength functions is used in describing the Breit-Wigner to Gaussian transition seen in neutral atoms CeI to SmI with valence electrons changing from 4 to 8.
Time-resolved diffusion tomographic imaging in highly scattering turbid media

NASA Technical Reports Server (NTRS)

Alfano, Robert R. (Inventor); Cai, Wei (Inventor); Liu, Feng (Inventor); Lax, Melvin (Inventor); Das, Bidyut B. (Inventor)

1998-01-01

A method for imaging objects in highly scattering turbid media. According to one embodiment of the invention, the method involves using a plurality of intersecting source/detectors sets and time-resolving equipment to generate a plurality of time-resolved intensity curves for the diffusive component of light emergent from the medium. For each of the curves, the intensities at a plurality of times are then inputted into the following inverse reconstruction algorithm to form an image of the medium: X.sup.(k+1).spsp.T =?Y.sup.T W+X.sup.(k).spsp.T .LAMBDA.!?W.sup.T W+.LAMBDA.!.sup.-1 wherein W is a matrix relating output at detector position r.sub.d, at time t, to source at position r.sub.s, .LAMBDA. is a regularization matrix, chosen for convenience to be diagonal, but selected in a way related to the ratio of the noise, to fluctuations in the absorption (or diffusion) X.sub.j that we are trying to determine: .LAMBDA..sub.ij =.lambda..sub.j .delta..sub.ij with .lambda..sub.j =/<.DELTA.Xj.DELTA.Xj> Here Y is the data collected at the detectors, and X.sup.k is the kth iterate toward the desired absoption information.
Loss of photosynthetic efficiency in the shade. An Achilles heel for the dense modern stands of our most productive C4 crops?

PubMed Central

Pignon, Charles P.; Jaiswal, Deepak; McGrath, Justin M.

2017-01-01

Abstract The wild progenitors of major C4 crops grew as individuals subjected to little shading. Today they are grown in dense stands where most leaves are shaded. Do they maintain photosynthetic efficiency in these low light conditions produced by modern cultivation? The apparent maximum quantum yield of CO2 assimilation (ΦCO2max,app), a key determinant of light-limited photosynthesis, has not been systematically studied in field stands of C4 crops. ΦCO2max,app was derived from the initial slope of the response of leaf CO2 uptake (A) to photon flux (Q). Leaf fractional light absorptance (α) was measured to determine the absolute maximum quantum yield of CO2 assimilation on an absorbed light basis (ΦCO2max,abs). Light response curves were determined on sun and shade leaves of 49 field plants of Miscanthus × giganteus and Zea mays following canopy closure. ΦCO2max,app and ΦCO2max,abs declined significantly by 15–27% (P<0.05) with canopy depth. Experimentally, leaf age was shown unlikely to cause this loss. Modeling canopy CO2 assimilation over diurnal courses suggested that the observed decline in ΦCO2max,app with canopy depth costs 10% of potential carbon gain. Overcoming this limitation could substantially increase the productivity of major C4 crops. PMID:28110277
Spectral and temporal luminescent properties of Eu(III) in humic substance solutions from different origins.

PubMed

Brevet, Julien; Claret, Francis; Reiller, Pascal E

2009-10-01

Although a high heterogeneity of composition is awaited for humic substances, their complexation properties do not seem to greatly depend on their origins. The information on the difference in the structure of these complexes is scarce. To participate in the filling of this lack, a study of the spectral and temporal evolution of the Eu(III) luminescence implied in humic substance (HS) complexes is presented. Seven different extracts, namely Suwannee River fulvic acid (SRFA) and humic acid (SRHA), and Leonardite HA (LHA) from the International Humic Substances Society (USA), humic acid from Gorleben (GohyHA), and from the Kleiner Kranichsee bog (KFA, KHA) from Germany, and purified commercial Aldrich HA (PAHA), were made to contact with Eu(III). Eu(III)-HS time-resolved luminescence properties were compared with aqueous Eu(3+) at pH 5. Using an excitation wavelength of 394 nm, the typical bi-exponential luminescence decay for Eu(III)-HS complexes is common to all the samples. The components tau(1) and tau(2) are in the same order of magnitude for all the samples, i.e., 40 (7)F(2) transition exhibits the most striking differences. A slight blue shift is observed compared to aqueous Eu(3+) (lambda(max) = 615.4 nm), and the humic samples share almost the same lambda(max) approximately 614.5 nm. The main differences between the samples reside in a shoulder around lambda approximately 612.5 nm, modelled by a mixed Gaussian-Lorentzian band around lambda approximately 612 nm. SRFA shows the most intense shoulder with an intensity ratio of I(612.5)/I(614.7) = 1.1, KFA/KHA/SRHA share almost the same ratio I(612.5)/I(614.7) = 1.2-1.3, whilst the LHA/GohyHA/PAHA group has a I(612.5)/I(614.5) = 1.5-1.6. This shows that for the two groups of complexes, despite comparable complexing properties, slightly different symmetries are awaited.
Effect of a prior intermittent run at vVO2max on oxygen kinetics during an all-out severe run in humans.

PubMed

Billat, V L; Bocquet, V; Slawinski, J; Laffite, L; Demarle, A; Chassaing, P; Koralsztein, J P

2000-09-01

The purpose of this study was to examine the influence of prior intermittent running at VO2max on oxygen kinetics during a continuous severe intensity run and the time spent at VO2max. Eight long-distance runners performed three maximal tests on a synthetic track (400 m) whilst breathing through the COSMED K4 portable telemetric metabolic analyser: i) an incremental test which determined velocity at the lactate threshold (vLT), VO2max and velocity associated with VO2max (vVO2max), ii) a continuous severe intensity run at vLT+50% (vdelta50) of the difference between vLT and vVO2max (91.3+/-1.6% VO2max)preceded by a light continuous 20 minute run at 50% of vVO2max (light warm-up), iii) the same continuous severe intensity run at vdelta50 with a prior interval training exercise (hard warm-up) of repeated hard running bouts performed at 100% of vVO2max and light running at 50% of vVO2max (of 30 seconds each) performed until exhaustion (on average 19+/-5 min with 19+/-5 interval repetitions). This hard warm-up speeded the VO2 kinetics: the time constant was reduced by 45% (28+/-7 sec vs 51+/-37 sec) and the slow component of VO2 (deltaVO2 6-3 min) was deleted (-143+/-271 ml x min(-1) vs 291+/-153 ml x min(-1)). In conclusion, despite a significantly lower total run time at vdelta50 (6 min 19+/-0) min 17 vs 8 min 20+/-1 min 45, p=0.02) after the intermittent warm-up at VO2max, the time spent specifically at VO2max in the severe continuous run at vdelta50 was not significantly different.
Transformations of the distribution of nuclei formed in a nucleation pulse: Interface-limited growth.

PubMed

Shneidman, Vitaly A

2009-10-28

A typical nucleation-growth process is considered: a system is quenched into a supersaturated state with a small critical radius r( *) (-) and is allowed to nucleate during a finite time interval t(n), after which the supersaturation is abruptly reduced to a fixed value with a larger critical radius r( *) (+). The size-distribution of nucleated particles f(r,t) further evolves due to their deterministic growth and decay for r larger or smaller than r( *) (+), respectively. A general analytic expressions for f(r,t) is obtained, and it is shown that after a large growth time t this distribution approaches an asymptotic shape determined by two dimensionless parameters, lambda related to t(n), and Lambda=r( *) (+)/r( *) (-). This shape is strongly asymmetric with an exponential and double-exponential cutoffs at small and large sizes, respectively, and with a broad near-flat top in case of a long pulse. Conversely, for a short pulse the distribution acquires a distinct maximum at r=r(max)(t) and approaches a universal shape exp[zeta-e(zeta)], with zeta proportional to r-r(max), independent of the pulse duration. General asymptotic predictions are examined in terms of Zeldovich-Frenkel nucleation model where the entire transient behavior can be described in terms of the Lambert W function. Modifications for the Turnbull-Fisher model are also considered, and analytics is compared with exact numerics. Results are expected to have direct implementations in analysis of two-step annealing crystallization experiments, although other applications might be anticipated due to universality of the nucleation pulse technique.
The nature of unusual luminescence in natural calcite, CaCO3

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

Gaft, M.; Nagli, L.; Panczer, G.

2008-11-01

The unusual luminescence of particular varieties of natural pink calcite (CaCO{sub 3}) samples was studied by laser-induced time-resolved luminescence spectroscopy at different temperatures. The luminescence is characterized by intense blue emission under short-wave UV lamp excitation with an extremely long decay time, accompanied by pink-orange luminescence under long wave UV excitation. Our investigation included optical absorption, natural thermostimulated luminescence (NTL) and Laser-Induced Breakdown Spectroscopy (LIBS) studies. Two luminescence centers were detected: a narrow violet band, with {lambda}{sub max} = 412 nm, {Delta} = 45 nm, two decay components of {tau}{sub 1} = 5 ns and {tau}{sub 2} = 7.2 ms,more » accompanied by very long afterglow, and an orange emission band with {lambda}{sub max} = 595 nm, {Delta} = 90 nm and {tau} = 5 ns. Both luminescence centers are thermally unstable with the blue emission disappearing after heating at 500 C, and the orange emission disappearing after heating at different temperatures starting from 230 C, although sometimes it is stable up to 500 C in different samples. Both centers have spectral-kinetic properties very unusual for mineral luminescence, which in combination with extremely low impurity concentrations, prevent their identification with specific impurity related emission. The most likely explanation of these observations may be the presence of radiation-induced luminescence centers. The long violet afterglow is evidently connected with trapped charge carrier liberation, with their subsequent migration through the valence band and ultimate recombination with a radiation-induced center responsible for the unusual violet luminescence.« less
Photochemistry and reactivity of the phenyl radical-water system: a matrix isolation and computational study.

PubMed

Mardyukov, Artur; Crespo-Otero, Rachel; Sanchez-Garcia, Elsa; Sander, Wolfram

2010-08-02

The reaction of the phenyl radical 1 with water has been investigated by using matrix isolation spectroscopy and quantum chemical calculations. The primary thermal product of the reaction between 1 and water is a weakly bound complex stabilized by an OH...pi interaction. This complex is photolabile, and visible-light irradiation (lambda>420 nm) results in hydrogen atom transfer from water to radical 1 and the formation of a highly labile complex between benzene and the OH radical. This complex is stable under the conditions of matrix isolation, however, continuous irradiation with lambda>420 nm light results in the complete destruction of the aromatic system and formation of an acylic unsaturated ketene. The mechanisms of all reaction steps are discussed in the light of ab initio and DFT calculations.
The role of free kappa and lambda light chains in the pathogenesis and treatment of inflammatory diseases.

PubMed

Esparvarinha, Mojgan; Nickho, Hamid; Mohammadi, Hamed; Aghebati-Maleki, Leili; Abdolalizadeh, Jalal; Majidi, Jafar

2017-07-01

Kappa (κ) or lambda (λ) free light chains (FLCs) are produced from B cells during immunoglobulin synthesis. FLCs have been shown to participate in several key processes of immune responses. They are necessary to adjust PMN functions and assist PMN pre-stimulation. Moreover, they cause mast cell degranulation which releases pro-inflammatory mediators and stimulates local inflammatory responses in some conditions such as inflammatory bowel disease (IBD). Having low molecular weights which may straightly be toxic to proximal tubule cells (PTCs), FLCs can also have an important role in renal diseases. In this review we have highlighted the involvement of light chains in the pathogenesis of some inflammatory diseases and discussed their potential to be the targets of therapeutic purposes. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Max Graf's "Reminiscences of Professor Sigmund Freud" revisited: new evidence from the Freud archives.

PubMed

Wakefield, Jerome C

2007-01-01

Recently derestricted Freud Archive interviews with Max and Herbert Graf and Herbert's wife shed new light on Max Graf's article, "Reminiscences of Professor Sigmund Freud," published in The Psychoanalytic Quarterly in 1942. To explain discrepancies between the interviews and the earlier article, the author postulates that, in the article, Max Graf purposely distorted or omitted certain details in order not to reveal Herbert's identity as "Little Hans" (Freud 1909). The interviews place incidents reported in the article in a new and more complex light, and also underscore the intensely personal nature of the intellectual development of the psychoanalytic movement.
Subset of Kappa and Lambda Germline Sequences Result in Light Chains with a Higher Molecular Mass Phenotype.

PubMed

Barnidge, David R; Lundström, Susanna L; Zhang, Bo; Dasari, Surendra; Murray, David L; Zubarev, Roman A

2015-12-04

In our previous work, we showed that electrospray ionization of intact polyclonal kappa and lambda light chains isolated from normal serum generates two distinct, Gaussian-shaped, molecular mass distributions representing the light-chain repertoire. During the analysis of a large (>100) patient sample set, we noticed a low-intensity molecular mass distribution with a mean of approximately 24 250 Da, roughly 800 Da higher than the mean of the typical kappa molecular-mass distribution mean of 23 450 Da. We also observed distinct clones in this region that did not appear to contain any typical post-translational modifications that would account for such a large mass shift. To determine the origin of the high molecular mass clones, we performed de novo bottom-up mass spectrometry on a purified IgM monoclonal light chain that had a calculated molecular mass of 24 275.03 Da. The entire sequence of the monoclonal light chain was determined using multienzyme digestion and de novo sequence-alignment software and was found to belong to the germline allele IGKV2-30. The alignment of kappa germline sequences revealed ten IGKV2 and one IGKV4 sequences that contained additional amino acids in their CDR1 region, creating the high-molecular-mass phenotype. We also performed an alignment of lambda germline sequences, which showed additional amino acids in the CDR2 region, and the FR3 region of functional germline sequences that result in a high-molecular-mass phenotype. The work presented here illustrates the ability of mass spectrometry to provide information on the diversity of light-chain molecular mass phenotypes in circulation, which reflects the germline sequences selected by the immunoglobulin-secreting B-cell population.
X-Ray Flare Characteristics in the B2e Star Lambda Eridani (ROSAT)

NASA Technical Reports Server (NTRS)

Smith, Myron A.

1997-01-01

We document the results of a simultaneous wavelength monitoring on the B2e star (lambda) Eri. This campaign was carried out from ground stations and with the ROSAT, ASCA, IUE, and Voyager 2 space platforms during a week in February-March 1995; a smaller follow-up was conducted in September 1995. During the first of these intervals (lambda) Eri exhibited extraordinary wind and disk-ejection activity. The ROSAT/HRI X-ray light curves showed no large flares such as the one the ROSAT/PSCA observed in 1991. However, possible low level fluctuations in the February-March ROSAT data occurred at the same time as unusual activity in H(alpha) He I (lambda)6678, He II (lambda)1640, and the C IV doublet. For example, the hydrogen and helium lines exhibited an emission in the blue half of their profiles, probably lasting several hours. The C IV lines showed a strong high-velocity Discrete Absorption Component (DAC) accompanied by unusually strong absorption at lower velocities. The helium line activity suggests that a mass ejection occurred at the base of the wind while the strong C III (Voyager) and C IV (IUE) lines implies that shock interactions occurred in the wind flow. It is not clear that the X-ray elevations are directly related to the strong C IV absorptions because the former changed on a much more rapid timescale than absorptions in the C IV lines. Within hours of the mild X-ray flux variations found by ROSAT on February 28, the Voyager UVS observed a "ringing" that decayed over three 3-hr. cycles. The amplitude of these fluctuations was strong (50%) at (lambda)(lambda)950-1100, decreased rapidly with wavelength, and faded to nondetection longward of (lambda)1300. Various considerations indicate that these continuum variations were not due to an instrumental pathology in the UVS. Rather, they appear to be due to a time-dependent flux deficit in the (lambda)(lambda)950-1250 region. We outline a scenario in which a dense plasma structure over the star's surface is heated and cooled quasi-periodically to produce such flux changes. Observations of new examples of this phenomenon are badly needed. Amateur astronomers can make a significant contribution to its understanding by searching for ringing in light curves of Be stars during their outburst phases. Finally we draw attention to an increase in the emission of the H(alpha) line that occurred at about the time the FUV ringing started. This increased emission hints that approximately 50,000K plasma near the star's surface can influence the circumstellar disc at approximately 12R. by its increased Lyman continuum flux.
Serum free light chains, interferon-alpha, and interleukins in systemic lupus erythematosus.

PubMed

Jolly, M; Francis, S; Aggarwal, R; Mikolaitis, R A; Niewold, T B; Chubinskaya, S; Block, J A; Scanzello, C; Sequeira, W

2014-08-01

Interleukin-6 (IL-6), interleukin-10 (IL-10), interferon-alpha (IFN-α), and free light chains (FLCs: lambda, kappa) have all been noted to be of importance in systemic lupus erythematosus (SLE). Herein, we quantified and explored the relationship between these inflammatory mediators and disease activity in SLE; and stratified by their current anti-dsDNA antibody status. Seventy-seven SLE patients underwent assessment of disease activity using the SLE disease activity index (SLEDAI). Serum FLC (lambda, kappa, and total), IL-6, IL-10, and IFN-α were quantified. Demographics of disease characteristics were determined by chart reviews. Statistical analyses included Mann-Whitney test, chi square, and linear regression analyses. Mean (SD) age of the patients was 44.9 ± 12.7 years; SLEDAI (mean ± SD) was 3.4 ± 4.0. Serum lambda FLC levels had a moderate correlation (r = 0.46 with physician global assessment, 0.44 with SLEDAI) and the strongest correlation with disease activity as compared with other inflammatory mediators including current dsDNA antibody status. After adjusting for prednisone use, the correlation of lambda FLC with PGA (r = 0.48) and SLEDAI (r = 0.52) was better than of current dsDNA antibody status with PGA (r = 0.33) and adjusted SLEDAI (r = 0.24), respectively. IL-10 and IFN-α activity did not correlate with disease activity. Serum FLC and IL-6 levels could differentiate between active and inactive SLE patients. Serum lambda FLC and IL-6 levels differed significantly among patients with and without current dsDNA antibodies. Serum lambda FLC levels accounted for 31% of variance in SLEDAI scores. Serum FLC and IL-6 are potentially useful biomarkers of disease activity in SLE. Further studies, with larger study sample and longitudinal design, are indicated. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Ultrasensitive automated RNA in situ hybridization for kappa and lambda light chain mRNA detects B-cell clonality in tissue biopsies with performance comparable or superior to flow cytometry.

PubMed

Guo, Ling; Wang, Zhen; Anderson, Courtney M; Doolittle, Emerald; Kernag, Siobhan; Cotta, Claudiu V; Ondrejka, Sarah L; Ma, Xiao-Jun; Cook, James R

2018-03-01

The assessment of B-cell clonality is a critical component of the evaluation of suspected lymphoproliferative disorders, but analysis from formalin-fixed, paraffin-embedded tissues can be challenging if fresh tissue is not available for flow cytometry. Immunohistochemical and conventional bright field in situ hybridization stains for kappa and lambda are effective for evaluation of plasma cells but are often insufficiently sensitive to detect the much lower abundance of light chains present in B-cells. We describe an ultrasensitive RNA in situ hybridization assay that has been adapted for use on an automated immunohistochemistry platform and compare results with flow cytometry in 203 consecutive tissues and 104 consecutive bone marrows. Overall, in 203 tissue biopsies, RNA in situ hybridization identified light chain-restricted B-cells in 85 (42%) vs 58 (29%) by flow cytometry. Within 83 B-cell non-Hodgkin lymphomas, RNA in situ hybridization identified restricted B-cells in 74 (89%) vs 56 (67%) by flow cytometry. B-cell clonality could be evaluated in only 23/104 (22%) bone marrow cases owing to poor RNA preservation, but evaluable cases showed 91% concordance with flow cytometry. RNA in situ hybridization allowed for recognition of biclonal/composite lymphomas not identified by flow cytometry and highlighted unexpected findings, such as coexpression of kappa and lambda RNA in 2 cases and the presence of lambda light chain RNA in a T lymphoblastic lymphoma. Automated RNA in situ hybridization showed excellent interobserver reproducibility for manual evaluation (average K=0.92), and an automated image analysis system showed high concordance (97%) with manual evaluation. Automated RNA in situ hybridization staining, which can be adopted on commonly utilized immunohistochemistry instruments, allows for the interpretation of clonality in the context of the morphological features in formalin-fixed, paraffin-embedded tissues with a clinical sensitivity similar or superior to flow cytometry.
Ultrasensitive Automated RNA in situ Hybridization for Kappa and Lambda Light Chain mRNA Detects B-cell Clonality in Tissue Biopsies with Performance Comparable or Superior to Flow Cytometry

PubMed Central

Guo, Ling; Wang, Zhen; Anderson, Courtney M.; Doolittle, Emerald; Kernag, Siobhan; Cotta, Claudiu V.; Ondrejka, Sarah L.; Ma, Xiao-Jun; Cook, James R.

2017-01-01

The assessment of B-cell clonality is a critical component of the evaluation of suspected lymphoproliferative disorders, but analysis from formalin fixed paraffin embedded tissues can be challenging if fresh tissue is not available for flow cytometry. Immunohistochemical and conventional bright field in situ hybridization stains for kappa and lambda are effective for evaluation of plasma cells, but are often insufficiently sensitive to detect the much lower abundance of light chains present in B cells. We describe an ultrasensitive RNA in situ hybridization assay which has been adapted for use on an automated immunohistochemistry platform and compare results with flow cytometry in 203 consecutive tissues and 104 consecutive bone marrows. Overall, in 203 tissue biopsies, RNA in situ hybridization identified light chain restricted B-cells in 85 (42%) vs. 58 (29%) by flow cytometry. Within 83 B-cell non-Hodgkin lymphomas, RNA in situ hybridization identified a restricted B-cells in 74 (89%) vs. 56 (67%) by flow cytometry. B-cell clonality could be evaluated in only 23/104 (22%) bone marrow cases due to poor RNA preservation, but evaluable cases showed 91% concordance with flow cytometry. RNA in situ hybridization allowed for recognition of biclonal/composite lymphomas not identified by flow cytometry, and highlighted unexpected findings, such as coexpression of kappa and lambda RNA in 2 cases and the presence of lambda light chain RNA in a T lymphoblastic lymphoma. Automated RNA in situ hybridization showed excellent interobserver reproducibility for manual evaluation (average K=0.92), and an automated image analysis system showed high concordance (97%) with manual evaluation. Automated RNA in situ hybridization staining, which can be adopted on commonly utilized immunohistochemistry instruments, allows for the interpretation of clonality in the context of the morphologic features in formalin fixed, paraffin embedded tissues with a clinical sensitivity similar or superior to flow cytometry. PMID:29052600

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

Kantowski, Ronald; Chen Bin; Dai Xinyu, E-mail: kantowski@nhn.ou.ed, E-mail: Bin.Chen-1@ou.ed, E-mail: dai@nhn.ou.ed

We compute the deflection angle to order (m/r {sub 0}){sup 2} and m/r{sub 0} x {Lambda}r {sup 2}{sub 0} for a light ray traveling in a flat {Lambda}CDM cosmology that encounters a completely condensed mass region. We use a Swiss cheese model for the inhomogeneities and find that the most significant correction to the Einstein angle occurs not because of the nonlinear terms but instead occurs because the condensed mass is embedded in a background cosmology. The Swiss cheese model predicts a decrease in the deflection angle of {approx}2% for weakly lensed galaxies behind the rich cluster A1689 and thatmore » the reduction can be as large as {approx}5% for similar rich clusters at z {approx} 1. Weak-lensing deflection angles caused by galaxies can likewise be reduced by as much as {approx}4%. We show that the lowest order correction in which {Lambda} appears is proportional to m/r{sub 0} x {radical}({Lambda}r{sub 0}{sup 2}) and could cause as much as a {approx}0.02% increase in the deflection angle for light that passes through a rich cluster. The lowest order nonlinear correction in the mass is proportional to m/r{sub 0}x{radical}(m/r{sub 0}) and can increase the deflection angle by {approx}0.005% for weak lensing by galaxies.« less
Light Weight Silicon Mirrors for Space Instrumentation

NASA Technical Reports Server (NTRS)

Bly, Vincent T.; Hill, Peter C.; Hagopian, John G.; Strojay, Carl R.; Miller, Timothy

2012-01-01

Each mirror is a monolithic structure from a single crystal of silicon. The mirrors are light weighted after the optical surface is ground and polished. Mirrors made during the initial phase of this work were typically 1/50 lambda or better (RMS at 633 n m)
A Single Mutation at the Sheet Switch Region Results in Conformational Changes Favoring 6 Light-Chain Fibrillogenesis

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

Hernández-Santoyo, A.; Del Pozo Yauner, L; Fuentes-Silva, D

Systemic amyloid light-chain (LC) amyloidosis is a disease process characterized by the pathological deposition of monoclonal LCs in tissue. All LC subtypes are capable of fibril formation although {lambda} chains, particularly those belonging to the {lambda}6 type, are overrepresented. Here, we report the thermodynamic and in vitro fibrillogenic properties of several mutants of the {lambda}6 protein 6aJL2 in which Pro7 and/or His8 was substituted by Ser or Pro. The H8P and H8S mutants were almost as stable as the wild-type protein and were poorly fibrillogenic. In contrast, the P7S mutation decreased the thermodynamic stability of 6aJL2 and greatly enhanced itsmore » capacity to form amyloid-like fibrils in vitro. The crystal structure of the P7S mutant showed that the substitution induced both local and long-distance effects, such as the rearrangement of the VL (variable region of the light chain)-VL interface. This mutant crystallized in two orthorhombic polymorphs, P2{sub 1}2{sub 1}2{sub 1} and C222{sub 1}. In the latter, a monomer that was not arranged in the typical Bence-Jones dimer was observed for the first time. Crystal-packing analysis of the C222{sub 1} lattice showed the establishment of intermolecular {beta}-{beta} interactions that involved the N-terminus and {beta}-strand B and that these could be relevant in the mechanism of LC fibril formation. Our results strongly suggest that Pro7 is a key residue in the conformation of the N-terminal sheet switch motif and, through long-distance interactions, is also critically involved in the contacts that stabilized the VL interface in {lambda}6 LCs.« less
Hypernuclear Weak Decays

NASA Astrophysics Data System (ADS)

Itonaga, K.; Motoba, T.

The recent theoretical studies of Lambda-hypernuclear weak decaysof the nonmesonic and pi-mesonic ones are developed with the aim to disclose the link between the experimental decay observables and the underlying basic weak decay interactions and the weak decay mechanisms. The expressions of the nonmesonic decay rates Gamma_{nm} and the decay asymmetry parameter alpha_1 of protons from the polarized hypernuclei are presented in the shell model framework. We then introduce the meson theoretical Lambda N -> NN interactions which include the one-meson exchanges, the correlated-2pi exchanges, and the chiral-pair-meson exchanges. The features of meson exchange potentials and their roles on the nonmesonic decays are discussed. With the adoption of the pi + 2pi/rho + 2pi/sigma + omega + K + rhopi/a_1 + sigmapi/a_1 exchange potentials, we have carried out the systematic calculations of the nonmesonic decay observables for light-to-heavy hypernuclei. The present model can account for the available experimental data of the decay rates, Gamma_n/Gamma_p ratios, and the intrinsic asymmetry parameters alpha_Lambda (alpha_Lambda is related to alpha_1) of emitted protons well and consistently within the error bars. The hypernuclear lifetimes are evaluated by converting the total weak decay rates Gamma_{tot} = Gamma_pi + Gamma_{nm} to tau, which exhibit saturation property for the hypernuclear mass A ≥ 30 and agree grossly well with experimental data for the mass range from light to heavy hypernuclei except for the very light ones. Future extensions of the model and the remaining problems are also mentioned. The pi-mesonic weak processes are briefly surveyed, and the calculations and predictions are compared and confirmed by the recent high precision FINUDA pi-mesonic decay data. This shows that the theoretical basis seems to be firmly grounded.
Membrane current of retinal rods of Caudiverbera caudiverbera (Amphibia: Leptodactylidae): dark noise, spectral and absolute light sensitivity.

PubMed

Palma, F; Roncagliolo, P; Bacigalupo, J; Palacios, A G

2001-01-01

We investigated the photocurrents from isolated rods of the South American anuran, Caudiverbera caudiverbera. Rod outer segments were on average 66.4 +/- 11.2 microm (mean +/- S.D., n = 104) in length and 6.6 +/- 0.9 microm (mean +/- S.D.) in diameter: 40 +/- 22 photoisomerizations (mean +/- S.D., range 10-99, n = 16) were required for eliciting a half-saturating photocurrent response. The time-to-peak was 911 +/- 217 ms (mean +/- S.D., n = 14, 20 degrees C) in the linear range of the response and the integration time of the current response was 1744 +/- 451 ms (mean +/- S.D., n = 14). The time-to-peak appears to be slower and the integration time shorter in Caudiverbera than in Ambystoma tigrinum, Rana pipiens or Xenopus laevis rods under similar experimental conditions. The a-band of rod spectral sensitivity has a lambda(max) at 520 +/- 2.1 nm (mean +/- S.D., range 516-525 nm, n = 24) and the bandwidth fits a porphyropsin visual pigment. The single-event response amplitude ranges from 0.31-0.51 pA, depending on the calculation method. The intrinsic dark current (variance at dark minus variance under bright light) was 0.045 +/- 0.040 pA2 (mean +/- S.D., n = 24). Our results support the presence of a dark-noise component below 1 Hz, with kinetics similar to the single-photon evoked response and a rate of 0.006 events s(-1) (n = 9).
Evidence for the formation of a quinone methide during the oxidation of the insect cuticular sclerotizing precursor 1,2-dehydro-N-acetyldopamine.

PubMed

Sugumaran, M; Semensi, V; Kalyanaraman, B; Bruce, J M; Land, E J

1992-05-25

1,2-Dehydro-N-acetyldopamine (dehydro-NADA) is an important catecholamine derivative involved in the cross-linking of insect cuticular components during sclerotization. Since sclerotization is a vital process for the survival of insects, and is closely related to melanogenesis, it is of interest to unravel the chemical mechanisms participating in this process. The present paper reports on the mechanism by which dehydro-NADA is oxidatively activated to form reactive intermediate(s) as revealed by pulse radiolysis, electron spin resonance spectroscopy, high performance liquid chromatography, and ultraviolet-visible spectroscopic analysis. Pulse radiolytic one-electron oxidation of dehydro-NADA by N3. (k = 5.3 x 10(9) M-1 s-1) or Br2.- (k = 7.5 x 10(8) M-1 s-1) at pH6 resulted in the rapid generation of the corresponding semiquinone radical, lambda max 400 nm, epsilon = 20,700 M-1 cm-1. This semiquinone decayed to form a second transient intermediate, lambda max 485 nm, epsilon = 8000 M-1 cm-1, via a second order disproportionation process, k = 6.2 x 10(8) M-1 s-1. At pH 6 in the presence of azide, the first order decay of this second intermediate occurred over milliseconds; the rate decreases at higher pH. At pH 6 in the presence of bromide, the intermediate decayed much more slowly over seconds, k = 0.15 s-1. Under such conditions, the dependence of the first order decay constant upon parent dehydro-NADA concentration led to a second order rate constant of 8.5 x 10(2) M-1 s-1 for reaction of the intermediate with the parent, probably to form benzodioxan "dimers." (The term dimer is used for convenience; the products are strictly bisdehydrodimers of dehydro-NADA (see "Discussion" and Fig. 11)) Rate constants of 5.9 x 10(5), 4.5 x 10(5), 2.8 x 10(4) and 3.5 x 10(4) M-1 s-1 were also obtained for decay of the second intermediate in the presence of cysteine, cysteamine, o-phenylenediamine, and p-aminophenol, respectively. By comparison with the UV-visible spectroscopic properties of the two-electron oxidized species derived from dehydro-NADA and from 1,2-dehydro-N-acetyldopa methyl ester, it is concluded that the transient intermediate exhibiting absorbance at 485 nm is the quinone methide tautomer of the o-quinone of dehydro-NADA. Sclerotization of insect cuticle is discussed in the light of these findings.
Development of a Highly Efficient Hybrid White Organic-Light-Emitting Diode with a Single Emission Layer by Solution Processing.

PubMed

Wu, Jun-Yi; Chen, Show-An

2018-02-07

We use a mixed host, 2,6-bis[3-(carbazol-9-yl)phenyl]pyridine blended with 20 wt % tris(4-carbazoyl-9-ylphenyl)amine, to lower the hole-injection barrier, along with the bipolar and high-photoluminescence-quantum-yield (Φ p = 84%), blue thermally activated delay fluorescence (TADF) material of 9,9-dimethyl-9,10-dihydroacridine-2,4,6-triphenyl-1,3,5-triazine (DMAC-TRZ) as a blue dopant to compose the emission layer for the fabrication of a TADF blue organic-light-emitting diode (BOLED). The device is highly efficient with the following performance parameters: maximum brightness (B max ) = 57586 cd/m 2 , maximum current efficiency (CE max ) = 35.3 cd/A, maximum power efficiency (PE max ) = 21.4 lm/W, maximum external quantum efficiency (EQE max ) = 14.1%, and CIE coordinates (0.18, 0.42). This device has the best performance recorded among the reported solution-processed TADF BOLEDs and has a low efficiency roll-off: at brightness values of 1000 and 5000 cd/m 2 , its CEs are close, being 35.1 and 30.1 cd/A, respectively. Upon further doping of the red phosphor Ir(dpm)PQ 2 (emission peak λ max = 595 nm) into the blue emission layer, we obtained a TADF-phosphor hybrid white organic-light-emitting diode (T-P hybrid WOLED) with high performance: B max = 43594 cd/m 2 , CE max = 28.8 cd/A, PE max = 18.1 lm/W, and CIE coordinates (0.38, 0.44). This B max = 43594 cd/m 2 is better than that of the vacuum-deposited WOLED with a blue TADF emitter, 10000 cd/m 2 . This is also the first report on a T-P hybrid WOLED with a solution-processed emitting layer.
Leaf traits in relation to crown development, light interception and growth of elite families of loblolly and slash pine.

PubMed

Chmura, Daniel J; Tjoelker, Mark G

2008-05-01

Crown architecture and size influence leaf area distribution within tree crowns and have large effects on the light environment in forest canopies. The use of selected genotypes in combination with silvicultural treatments that optimize site conditions in forest plantations provide both a challenge and an opportunity to study the biological and environmental determinants of forest growth. We investigated tree growth, crown development and leaf traits of two elite families of loblolly pine (Pinus taeda L.) and one family of slash pine (P. elliottii Mill.) at canopy closure. Two contrasting silvicultural treatments -- repeated fertilization and control of competing vegetation (MI treatment), and a single fertilization and control of competing vegetation treatment (C treatment) -- were applied at two experimental sites in the West Gulf Coastal Plain in Texas and Louisiana. At a common tree size (diameter at breast height), loblolly pine trees had longer and wider crowns, and at the plot-level, intercepted a greater fraction of photosynthetic photon flux than slash pine trees. Leaf-level, light-saturated assimilation rates (A(max)) and both mass- and area-based leaf nitrogen (N) decreased, and specific leaf area (SLA) increased with increasing canopy depth. Leaf-trait gradients were steeper in crowns of loblolly pine trees than of slash pine trees for SLA and leaf N, but not for A(max). There were no species differences in A(max), except in mass-based photosynthesis in upper crowns, but the effect of silvicultural treatment on A(max) differed between sites. Across all crown positions, A(max) was correlated with leaf N, but the relationship differed between sites and treatments. Observed patterns of variation in leaf properties within crowns reflected acclimation to developing light gradients in stands with closing canopies. Tree growth was not directly related to A(max), but there was a strong correlation between tree growth and plot-level light interception in both species. Growth efficiency was unaffected by silvicultural treatment. Thus, when coupled with leaf area and light interception at the crown and canopy levels, A(max) provides insight into family and silvicultural effects on tree growth.
Differentially expressed proteins of soybean (Glycine max) pulvinus in light and dark conditions

USDA-ARS?s Scientific Manuscript database

Soybean leaves (Glycine max) both track and avoid the sun through turgor changes of the pulvinus tissue at the base of leaves. Pulvinar response is known to be affected by both diurnally varying environmental factors and circadian patterns. Differential expression of the proteins between light and d...
Simultaneous X-ray, UV, and Optical Variations in lambda ERI (B2e)

NASA Astrophysics Data System (ADS)

Smith, M. A.; Murakami, T.; Anandarao, B.

1996-12-01

We have carried out a simultaneous observing campaign on the prototypical Be star lambda Eri using ground stations and ROSAT, ASCA, IUE, and Voyager spacecrafts during the week of February-March 1995; a smaller campaign was carried out the following September. In late February lambda Eri showed extraordinary disk-wind activity. ROSAT/HRI monitoring disclosed no large flares such as ROSAT observed in 1991 in lambda Eri. Possible low amplitude fluctuations in the 1995 data occurred at the same time with unusual activity in Hα , HeI lambda 6678, HeII lambda 1640, CIII, and the CIV doublet. The helium line activity suggests that mass ejection occurred at the base of the wind. The strong CIII and CIV lines implies that shock interactions originated in the wind flow. It is not clear that the X-ray fluctuations are directly related to the increases in wind line absorption. Within hours of the mild X-ray flux variations found by ROSAT on February 28, the Voyager UVS observed a ``ringing" that decayed over three 3-hr. cycles. The amplitude of these fluctuations was large (50%) at lambda lambda 950-1100, decreased rapidly with wavelength, and faded to nondetection above lambda 1300. Various considerations indicate that these continuum variations were not due to an instrument pathology in the UVS. Rather, they appear to be due to a time-dependent flux deficit in the lambda lambda 1250 during the minima of these cycles. We outline a scenario in which dense plasma over the star's surface is alternately heated and cooled quasi-periodically to produce the flux changes. Additional examples of this new phenomenon are needed. Amateur astronomers can make a significant contribution to the understanding of flickering in Be star light curves during their outburst phases. We also draw attention to an increase in the emission of the Hα line that occurred at about the same time the FUV ringing started. This increased emission hints that ~ 50,000K plasma near the star's surface can infuence the circumstellar disc some distance away by its increased Lyman continuum flux.
Global to Microscale Evolution of the Pinatubo Volcanic Aerosol Derived from Diverse Measurements and Analyses

NASA Technical Reports Server (NTRS)

Russell, P. B.; Livingston, J. M.; Pueschel, R. F.; Bauman, J. J.; Pollack, J. B.; Brooks, S. L.; Hamill, P.; Thomason, L. W.; Stowe, L. L.; Deshler, T.;

2000-01-01

We assemble data on the Pinatubo aerosol from space, air, and ground measurements, develop a composite picture, and assess the consistency and uncertainties of measurement and retrieval techniques. Satellite infrared spectroscopy, particle morphology, and evaporation temperature measurements agree with theoretical calculations in showing a dominant composition of H2SO4-H20 mixture, with H2SO4 weight fraction of 65-80% for most stratospheric temperatures and humidities. Important exceptions are (1) volcanic ash, present at all heights initially and just above the tropopause until at least March 1992, and (2) much smaller H2SO4 fractions at the low temperatures of high-latitude winters and the tropical tropopause. Laboratory spectroscopy and calculations yield wavelength- and temperature-dependent refractive indices for the H2SO4-H20 droplets. These permit derivation of particle size information from measured optical depth spectra, for comparison to impactor and optical-counter measurements. All three techniques paint a generally consistent picture of the evolution of R(sub eff), the effective radius. In the first month after the eruption, although particle numbers increased greatly, R(sub eff) outside the tropical core was similar to preeruption values of approx. 0.1 to 0.2 microns, because numbers of both small (r < 0.2 microns) and large (r > 0.6 microns) particles increased. In the next 3-6 months, extracore R(sub eff) increased to approx. 0.5 microns, reflecting particle growth through condensation and coagulation. Most data show that R(sub eff) continued to increase for about 1 year after the eruption. R(sub eff) values up to 0.6 - 0.8 microns or more are consistent with 0.38 - 1 micron optical depth spectra in middle to late 1992 and even later. However, in this period, values from in situ measurements are somewhat less. The difference might reflect in situ undersampling of the very few largest particles, insensitivity of optical depth spectra to the smallest particles, or the inability of flat spectra to place an upper limit on particle size. Optical depth spectra extending to wavelengths lambda > 1 micron are required to better constrain R(sub eff), especially for R(sub eff) > 0.4 microns. Extinction spectra computed from in situ size distributions are consistent with optical depth measurements; both show initial spectra with lambda(sub max) <= 0.42 microns, thereafter increasing to 0.78 <= lambda(sub max) <= 1 micron. Not until 1993 do spectra begin to show a clear return to the preeruption signature of lambda(sub max) <= 0.42 microns. The twin signatures of large R(sub eff) (> 0.3 microns) and relatively flat extinction spectra (0.4 - 1 microns) are among the longest-lived indicators of Pinatubo volcanic influence. They persist for years after the peaks in number, mass, surface area, and optical depth at all wavelengths <= 1 microns. This coupled evolution in particle size distribution and optical depth spectra helps explain the relationship between global maps of 0.5- and 1.0-micron optical depth derived from the Advanced Very High Resolution Radiometer (AVHRR) and Stratospheric Aerosol and Gas Experiment (SAGE) satellite sensors. However, there are important differences between the AVHRR and SAGE midvisible optical thickness products. We discuss possible reasons for these differences and how they might be resolved.

Apparatus Would Position Bright Spot On Projection Screen

NASA Technical Reports Server (NTRS)

Rayman, Marc D.

1996-01-01

Proposed apparatus aims beam of visible light at wavelength lambda(2) to create bright spot at desired position in image on projection screen. Intended to replace handheld laser and flashlight pointers lecturers sometimes use to indicate features in projected images. Beam of light cannot be inadvertently aimed toward audience.
Fluorescence resonance energy-transfer affects the determination of the affinity between ligand and proteins obtained by fluorescence quenching method.

PubMed

Xiao, Jianbo; Wei, Xinlin; Wang, Yuanfeng; Liu, Chunxi

2009-11-01

The interaction between esculin and serum albumins was investigated to illustrate that the fluorescence resonance energy-transfer (FRET) affects the determination of the binding constants obtained by fluorescence quenching method. The binding constants (K(a)) obtained by the double-logarithm curve for esculin-BSA and esculin-HSA were 1.02x10(7) and 2.07x10(4)L/mol, respectively. These results from synchronous fluorescence showed that the Tyr and Trp residues of HSA were affected more deeply than those in BSA. The excitation profile of esculin showed that in the presence of BSA and HSA, the S(0)-->S(1) transition of esculin (lambda(ex)(max) approximately 340nm) appears, which is similar to the lambda(em)(max) of BSA and HSA. The critical distance (R(0)) between BSA and esculin is higher than that of HSA, which showed that the affinity of esculin and HSA should be higher than that of BSA. After centrifugation, the concentrations of esculin bound to albumins were determined by means of the fluorescence of esculin. It was found that much more esculin was bound to HSA than to BSA. However, the bound models for BSA and HSA are almost the same. The concentration of esculin bound to serum albumin at first decreased with the addition of esculin and then increased. From above results, it can be concluded that the affinity of esculin and HSA should be higher than that of esculin and BSA. This example showed that in the presence of FRET, the binding constants between ligands and proteins based on fluorescence quenching might be deviated.
Origin of the color of Cv. rhapsody in blue rose and some other so-called "blue" roses.

PubMed

Gonnet, Jean-François

2003-08-13

Flowers of the rose cultivar Rhapsody in Blue display unusual colors, changing as they age, from a vivid red-purple to a lighter and duller purple, which are based on tonalities corresponding to hue angles between 340 and 320 degrees in the CIELAB scale. Unexpectedly, the chemical basis of these colors is among the simplest, featuring cyanin (cyanidin 3,5-di-O-glucoside), the most frequent anthocyanin in flowers, as the sole pigment and quercetin kaempferol glycosides as copigments at a relatively low copigment/pigment ratio (about 3/1), which usually produces magenta or red shades in roses. This color shift to bluer shades is coupled with the progressive accumulation of cyanin into vacuolar anthocyanic inclusions (AVIs), the occurrence of which increases as the petals grow older. In addition to the normal lambda(max) of cyanin at approximately 545 nm, the transmission spectra of live petals and of epidermal cells exhibit a second lambda(max) in the 620-625 nm range, the relative importance increasing with the presence of AVIs. In petals of fully opened flowers, the only pigmented structures in the vacuoles of epidermal cells are AVIs; their intense and massive absorption in the 520-640 nm area produces a much darker and bluer color than measured for the vacuolar solution present at the very first opening stage. Cyanin is probably "trapped" into AVIs at higher concentrations than would be possible in a vacuolar solution and in quinonoidal form, appearing purple-blue because of additional absorption in the 580-630 nm area. Quite similar pigmentation features were found in very ancient rose cultivars (cv. L'Evêque or Bleu Magenta), also displaying this type of so-called "blue" color.
Laser Radar Study Using Resonance Absorption for Remote Detection Of Air Pollutants

NASA Technical Reports Server (NTRS)

Igarashi, Takashi

1973-01-01

A laser radar using resonance absorption has an advantage of increased detection range and sensitivity compared with that achieved by Raman or resonance back scattering. In this paper, new laser radar system using resonance absorption is proposed and results obtained from this laser radar system are discussed. NO2, SO2 gas has an absorption spectrum at 4500 A and 3000 A respectively as shown in Fig. 1. A laser light including at least a set of an absorption peak (lambda)1 and a valley (lambda)2 is emitted into a pollutant atmosphere. The light reflected with a topographical reflector or an atmospheric Mie scattering as distributed reflectors is received and divided into two wavelength components (lambda)1 and (lambda)2. The laser radar system used in the investigation is shown in Fig', 2 and consists of a dye laser transmitter, an optical receiver with a special monochrometer and a digital processer. Table 1 shows the molecular constants of NO2, and SO2 and the dye laser used in this experiment. In this system, the absolute concentration of the pollutant gas can be measured in comparison with a standard gas cell. The concentration of NO2, SO2 as low as 0.1 ppm have been measured at 100 m depth resolution. For a 1 mJ laser output, the observable range of this system achieved up to 300 m using the distributed Mie reflector. The capability and technical limitation of the system will be discussed in detail.
Shear Bond Strength of Resin Buttons to Lithium Disilicate and Leucite Reinforced Feldspathic Restorations

DTIC Science & Technology

2016-05-01

Hydrofluoric acid, silane coupling agent, light cured composite and ceramic restoration specimens (10 of each IPS e.max and Empress). The surface treatment...cured composite and ceramic restoration specimens (10 of each IPS e.max and Empress). The surface treatment in group C was applied to all specimens...and light cured for 20 seconds. 4) Group D: 5% Hydrofluoric acid, silane coupling agent, light cured composite and ceramic restoration (10 of
New stable perfluoroallyl radical from perfluoro-2,4-dimethyl-3-ethylpentene-2 and its photoconversion reactions

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

Shvedova, M.K.; Allayarov, S.R.; Barkalov, I.M.

1988-05-01

The thermally and chemically stable perfluoroally radical is formed in the radiolysis of perfluoro-2, 4-dimethyl-3-ethylpentene-2. A phototransformation of this radical into other radicals takes place under the action of UV light (/lambda/ < 300 nm) which are thermally unstable. Samples containing up to 90% FMP and 10% of its isomers were placed into ampules made of quartz or SK-4B glass, which gave to EPR signal after irradiation; the ampules were evacuated to a pressure of 0.13 Pa, frozen to 77 K, and irradiated with /sup 60/Co /lambda/-quanta at 77 K with doses up to 200 kGy. Irradiation with UV lightmore » was performed at 77 K with light from a DRSh-1000 lamp.« less
Optical studies of photoactive states in mixed organic-inorganic hybrid perovskites stabilized in polymers

NASA Astrophysics Data System (ADS)

Kardynal, Beata; Xi, Lifei; Salim, Teddy; Borghardt, Sven; Stoica, Toma; Lam, Yeng Ming

2015-03-01

Mixed organic-inorganic hybrid perovskites MAX-PbY2(X,Y =I, Br,Cl) have been demonstrated as very attractive materials for absorbers of solar cells and active layers of light emitting diodes and optically driven lasers. The bandgap of the perovskites can be tuned by mixing halogen atoms in different ratios. In this presentation we study mixed MAX-PbY2(X,Y =I, Br, Cl) particles synthesized directly in protective polymer matrices as light emitters. Both, time integrated and time resolved photoluminescence have been used to study the materials. So synthesized MAX-PbX2 are very stable when measured at room temperature and in air with radiative recombination of photogenerated carriers as the main decay path. In contrast, MAX-PbY2 with mixed halogen atoms display luminescence from sub-bandgap states which saturate at higher excitation levels. The density of these states depends on the used polymer matrix and increases upon illumination. We further compare the MAX-PbY2 synthesized in polymers and as films and show that these states are inherent to the material rather than its microstructure. This works has been supported by EU NWs4LIGHT grant.
[Excitation transfer between high-lying states in K2 in collisions with ground state K and H2 molecules].

PubMed

Shen, Xiao-Yan; Liu, Jing; Dai, Kang; Shen, Yi-Fan

2010-02-01

Pure potassium vapor or K-H2 mixture was irradiated in a glass fluorescence cell with pulses of 710 nm radiation from an OPO laser, populating K2 (1lambda(g)) state by two-photon absorption. Cross sections for 1lambda(g)-3lambda(g) transfer in K2 were determined using methods of molecular fluorescence. During the experiments with pure K vapor, the cell temperature was varied between 553 and 603 K. The K number density was determined spectroscopically by the white-light absorption measurement in the blue wing of the self-broadened resonance D2 line. The resulting fluorescence included a direct component emitted in the decay of the optically excitation and a sensitized component arising from the collisionally populated state. The decay signal of time-resolved fluorescence from1lambda(g) -->1 1sigma(u)+ transition was monitored. It was seen that just after the laser pulse the fluorescence of the photoexcited level decreased exponentially. The effective lifetimes of the 1lambda(g) state can be resolved. The plot of reciprocal of effective lifetimes of the 1lambda(g) state against K densities yielded the slope that indicated the total cross section for deactivation and the intercept that provided the radiative lifetime of the state. The radiative lifetime (20 +/- 2) ns was obtained. The cross section for deactivation of the K2(1lambda(g)) molecules by collisions with K is (2.5 +/- 0.3) x 10(-14) cm2. The time-resolved intensities of the K23lambda(g) --> 1 3sigma(u)+ (484 nm) line were measured. The radiative lifetime (16.0 +/- 3.2) ns and the total cross section (2.5 +/- 0.6) x 10(-14) cm2 for deactivation of the K2 (3lambda(g)) state can also be determined through the analogous procedure. The time-integrated intensities of 1lambda(g) --> 1 1sigma(u)+ and 3lambda(g) --> 1 3sigma(u)+ transitions were measured. The cross section (1.1 +/- 0.3) x10(-14) cm2 was obtained for K2 (1lambda(g))+ K --> K2 (3lambda(g)) + K collisions. During the experiments with K-H2 mixture, the cell temperature was kept constant at 553 K. The H2 pressure was varied between 40 and 400 Pa. The effects of K2-K collisions could not be neglected. These effects were subtracted out using the results of the pure K experiments. The cross section (2.7 +/- 1.1) x 10(-15) cm2 was obtained for K2 (1lambda(g)) + H2 --> K2 (3lambda(g))+H2 collisions. The cross section is (6.8 +/- 2.7) x 10(-15) cm2 for K2 (3lambda(g)) + H2 --> states out of K2 (3lambda(g)) + H2 collisions.
Hydrostatic constraints on morphological exploitation of light in tall Sequoia sempervirens trees.

PubMed

Ishii, Hiroaki T; Jennings, Gregory M; Sillett, Stephen C; Koch, George W

2008-07-01

We studied changes in morphological and physiological characteristics of leaves and shoots along a height gradient in Sequoia sempervirens, the tallest tree species on Earth, to investigate whether morphological and physiological acclimation to the vertical light gradient was constrained by hydrostatic limitation in the upper crown. Bulk leaf water potential (Psi) decreased linearly and light availability increased exponentially with increasing height in the crown. During the wet season, Psi was lower in the outer than inner crown. C isotope composition of leaves (delta(13)C) increased with increasing height indicating greater photosynthetic water use efficiency in the upper crown. Leaf and shoot morphology changed continuously with height. In contrast, their relationships with light availability were discontinuous: morphological characteristics did not correspond to increasing light availability above 55-85 m. Mass-based chlorophyll concentration (chl) decreased with increasing height and increasing light availability. In contrast, area-based chl remained constant or increased with increasing height. Mass-based maximum rate of net photosynthesis (P (max)) decreased with increasing height, whereas area-based P (max) reached maximum at 78.4 m and decreased with increasing height thereafter. Mass-based P (max) increased with increasing shoot mass per area (SMA), whereas area-based P (max) was not correlated with SMA in the upper crown. Our results suggest that hydrostatic limitation of morphological development constrains exploitation of light in the upper crown and contributes to reduced photosynthetic rates and, ultimately, reduced height growth at the tops of tall S. sempervirens trees.

Starspot evolution, differential rotation, and magnetic cycles in the chromospherically active binaries lambda andromedae, sigma Geminorum, II Pegasi, and V711 Tauri

NASA Technical Reports Server (NTRS)

Henry, Gregory W.; Eaton, Joel A.; Hamer, Jamesia; Hall, Douglas S.

1995-01-01

We have analyzed 15-19 yr of photoelectric photometry, obtained manually and with automated telescopes, of the chromospherically active binaries lambda And, sigma Gem, II Peg, and V711 Tau. These observations let us identify individual dark starspots on the stellar surfaces from periodic dimming of the starlight, follow the evolution of these spots, and search for long-term cyclic changes in the properties of these starspots that might reveal magnetic cycles analogous to the Sun's 11 yr sunspot cycle. We developed a computer code to fit a simple two-spot model to our observed light curves that allows us to extract the most easily determinable and most reliable spot parameters from the light curves, i.e., spot longitudes and radii. We then used these measured properties to identify individual spots and to chart their life histories by constructing migration and amplitude curves. We identified and followed 11 spots in lambda And, 16 in sigma Gem, 12 in II Peg, and 15 in V711 Tau. Lifetimes of individual spots ranged from a few months to longer than 6 yr. Differential rotation coefficients, estimated from the observed range of spot rotation periods for each star and defined by equation (2), were 0.04 for lambda And, 0.038 for sigma Gem, 0.005 for II Peg, and 0.006 for V711 Tau, versus 0.19 for the Sun. We searched for cyclic changes in mean brightness, B-V color index, and spot rotation period as evidence for long-term cycles. Of these, long-term variability in mean brightness appears to offer the best evidence for such cycles in these four stars. Cycles of 11.1 yr for lambda And, 8.5 yr for sigma Gem, 11 yr for II Peg, and 16 yr V711 Tau are implied by these mean brightness changes. Cyclic changes in spot rotation period were found in lambda And and possibly II Peg. Errors in B-V were too large for any long-term changes to be detectable.
Dust in the Small Magellanic Cloud

NASA Technical Reports Server (NTRS)

Rodrigues, C. V.; Coyne, G. V.; Magalhaes, A. M.

1995-01-01

We discuss simultaneous dust model fits to our extinction and polarization data for the Small Magellanic Cloud (SMC) using existing dust models. Dust model fits to the wavelength dependent polarization are possible for stars with small lambda(sub max). They generally imply size distributions which are narrower and have smaller average sizes compared to those in the Galaxy. The best fits for the extinction curves are obtained with a power law size distribution. The typical, monotonic SMC extinction curve can be well fit with graphite and silicate grains if a small fraction of the SMC carbon is locked up in the grains. Amorphous carbon and silicate grains also fit the data well.
Diffuse interstellar bands in reflection nebulae

NASA Technical Reports Server (NTRS)

Fischer, O.; Henning, Thomas; Pfau, Werner; Stognienko, R.

1994-01-01

A Monte Carlo code for radiation transport calculations is used to compare the profiles of the lambda lambda 5780 and 6613 Angstrom diffuse interstellar bands in the transmitted and the reflected light of a star embedded within an optically thin dust cloud. In addition, the behavior of polarization across the bands were calculated. The wavelength dependent complex indices of refraction across the bands were derived from the embedded cavity model. In view of the existence of different families of diffuse interstellar bands the question of other parameters of influence is addressed in short.
Variation in light-intercepting area and photosynthetic rate of sun and shade shoots of two Picea species in relation to the angle of incoming light.

PubMed

Ishii, Hiroaki; Hamada, Yoko; Utsugi, Hajime

2012-10-01

We investigated the effects of sun- and shade-shoot architecture on the photosynthetic rates of two Picea species by applying light from various angles in the laboratory. Compared with sun shoots, shade shoots were characterized by lower mass allocation per light-intercepting area, less leaf mass per shoot mass, less mutual shading among leaves and more efficient allocation of chlorophyll to photosynthesis. The shoot silhouette to total leaf area ratio (STAR(ϕ)) decreased with increasing shoot inclination angle (ϕ, the shoot axis angle relative to the projection plane) and was consistently higher for the shade shoots. Morphological and physiological characteristics of the shade shoots resulted in maximum rates of net photosynthesis at ϕ = 0° (P(max,0)) similar to that of the sun shoots when expressed on a leaf mass, total leaf area and chlorophyll basis. When the angle of incoming light was varied, P(max,ϕ) per total leaf area (P(max,ϕ )/A(T)) of the shade shoots increased linearly with increasing STAR(ϕ), while P(max,ϕ) per shoot silhouette area did not change. In contrast, the response of the sun shoots was non-linear, and an optimum angle of incoming light was determined. Our results suggest that shade-shoot morphology is adaptive for utilizing diffuse light incoming from various angles, while sun-shoot morphology is adaptive for avoiding the negative effects of strong direct radiation and for enhancing light diffusion into the canopy. We propose that the angle of incoming light should be taken into account when estimating photosynthetic rates of sun shoots of conifer trees in the field.
Adaptive spatial filtering using photochromic glass

NASA Astrophysics Data System (ADS)

Potton, R. J.

1999-12-01

Commercially available photochromic glasses exhibit a wide range of spectral sensitivities and darkening response times. Short wavelengths are more effective than long ones for causing darkening but at least one type of glass is effectively darkened by red light (icons/Journals/Common/lambda" ALT="lambda" ALIGN="TOP"/> = 633 nm) with an intensity of about 1 kW m-2. Used as adaptive spatial filters, these glasses attenuate a wavefront by an amount that depends on their recent exposure to light. One type of optical processing that can be performed with such filters is drift nulling in an interferometer excited by light of a wavelength within the sensitivity spectrum of the photochrome. This form of processing has been demonstrated by dithering the speckle pattern in a single-fibre multimode interferometer. The dither allows phase-sensitive detection techniques to be used in the detection of signal-induced phase variations in a frequency band extending from the inverse response time of the photochrome to the dither frequency.
Study on improving the turbidity measurement of the absolute coagulation rate constant.

PubMed

Sun, Zhiwei; Liu, Jie; Xu, Shenghua

2006-05-23

The existing theories dealing with the evaluation of the absolute coagulation rate constant by turbidity measurement were experimentally tested for different particle-sized (radius = a) suspensions at incident wavelengths (lambda) ranging from near-infrared to ultraviolet light. When the size parameter alpha = 2pi a/lambda > 3, the rate constant data from previous theories for fixed-sized particles show significant inconsistencies at different light wavelengths. We attribute this problem to the imperfection of these theories in describing the light scattering from doublets through their evaluation of the extinction cross section. The evaluations of the rate constants by all previous theories become untenable as the size parameter increases and therefore hampers the applicable range of the turbidity measurement. By using the T-matrix method, we present a robust solution for evaluating the extinction cross section of doublets formed in the aggregation. Our experiments show that this new approach is effective in extending the applicability range of the turbidity methodology and increasing measurement accuracy.
Vapochromic LED

DOEpatents

Kunugi, Yoshihito; Mann, Kent R.; Miller, Larry L.; Exstrom, Christopher L.

2003-06-17

A sandwich device was prepared by electrodeposition of an insoluble layer of oligomerized tris(4-(2-thienyl)phenyl)amine onto conducting indium-tin oxide coated glass, spin coating the stacked platinum compound, tetrakis(p-decylphenylisocyano)platinum tetranitroplatinate, from toluene onto the oligomer layer, and then coating the platinum complex with aluminum by vapor deposition. This device showed rectification of current and gave electroluminescence. The electroluminescence spectrum (.lambda..sub.max =545 nm) corresponded to the photoluminescence spectrum of the platinum complex. Exposure of the device to acetone vapor caused the electroemission to shift to 575 nm. Exposure to toluene vapor caused a return to the original spectrum. These results demonstrate a new type of sensor that reports the arrival of organic vapors with an electroluminescent signal. The sensor comprises (a) a first electrode; (b) a hole transport layer formed on the first electrode; (c) a sensing/emitting layer formed on the hole transport layer, the sensing/emitting layer comprising a material that changes color upon exposure to the analyte vapors; (d) an electron conductor layer formed on the sensing layer; and (e) a second electrode formed on the electron conductor layer. The hole transport layer emits light at a shorter wavelength than the sensing/emitting layer and at least the first electrode comprises an optically transparent material.
Sensitive spectroscopic detection of large and denatured protein aggregates in solution by use of the fluorescent dye Nile red.

PubMed

Sutter, Marc; Oliveira, Sabrina; Sanders, Niek N; Lucas, Bart; van Hoek, Arie; Hink, Mark A; Visser, Antonie J W G; De Smedt, Stefaan C; Hennink, Wim E; Jiskoot, Wim

2007-03-01

The fluorescent dye Nile red was used as a probe for the sensitive detection of large, denatured aggregates of the model protein beta-galactosidase (E. coli) in solution. Aggregates were formed by irreversible heat denaturation of beta-galactosidase below and above the protein's unfolding temperature of 57.4 degrees C, and the presence of aggregates in heated solutions was confirmed by static light scattering. Interaction of Nile red with beta-galactosidase aggregates led to a shift of the emission maximum (lambda (max)) from 660 to 611 nm, and to an increase of fluorescence intensity. Time-resolved fluorescence and fluorescence correlation spectroscopy (FCS) measurements showed that Nile red detected large aggregates with hydrodynamic radii around 130 nm. By steady-state fluorescence measurements, it was possible to detect 1 nM of denatured and aggregated beta-galactosidase in solution. The comparison with size exclusion chromatography (SEC) showed that native beta-galactosidase and small aggregates thereof had no substantial effect on the fluorescence of Nile red. Large aggregates were not detected by SEC, because they were excluded from the column. The results with beta-galactosidase demonstrate the potential of Nile red for developing complementary analytical methods that overcome the size limitations of SEC, and can detect the formation of large protein aggregates at early stages.
[A case of IgA2-lambda type M-protein that IgA concentration differs from the values of M-protein by serum protein electrophoresis].

PubMed

Fukushima, M; Sugano, M; Ichikawa, T; Honda, T; Totsuka, M; Katsuyama, T; Fujita, K

2001-07-01

We report an IgA-lambda type M-protein in which the IgA concentration differed from the values of M-protein by serum protein electrophoresis found in a 53-year-old man with multiple myeloma. The M-protein value as determined by serum protein electrophoresis was 6,170 mg/dl. However, the serum IgA concentration was 3,052 mg/dl by turbidimetric immunoassay. Immuno-fixation electrophoresis using IgA subclass antisera revealed that this M-protein was the IgA2-lambda type. Western blotting analysis showed that the IgA2 molecules were composed of two approximately 68 kDa alpha 2 chains and two 28 kDa lambda chains. In addition the free lambda chain band was detected at the position of 28 kDa without 2-mercaptoethanol(2-ME) even though the patient IgA was purified. Since it is known that IgA2m(1) allotype easily release light chains from the IgA molecules in SDS-PAGE without 2-ME, we speculated that in this patient the IgA was the IgA2m(1) allotype. After peripheral blood stem cell transplantation(PBSCT), immunofixation electrophoresis of the patient serum revealed not only the bands of IgA2-lambda type M-protein, but also three bands of IgG1-kappa type M-protein in the gamma region.
Optical fiber sensor having an active core

NASA Technical Reports Server (NTRS)

Egalon, Claudio Oliveira (Inventor); Rogowski, Robert S. (Inventor)

1993-01-01

An optical fiber is provided. The fiber is comprised of an active fiber core which produces waves of light upon excitation. A factor ka is identified and increased until a desired improvement in power efficiency is obtained. The variable a is the radius of the active fiber core and k is defined as 2 pi/lambda wherein lambda is the wavelength of the light produced by the active fiber core. In one embodiment, the factor ka is increased until the power efficiency stabilizes. In addition to a bare fiber core embodiment, a two-stage fluorescent fiber is provided wherein an active cladding surrounds a portion of the active fiber core having an improved ka factor. The power efficiency of the embodiment is further improved by increasing a difference between the respective indices of refraction of the active cladding and the active fiber core.
Lagrange constraint neural network for audio varying BSS

NASA Astrophysics Data System (ADS)

Szu, Harold H.; Hsu, Charles C.

2002-03-01

Lagrange Constraint Neural Network (LCNN) is a statistical-mechanical ab-initio model without assuming the artificial neural network (ANN) model at all but derived it from the first principle of Hamilton and Lagrange Methodology: H(S,A)= f(S)- (lambda) C(s,A(x,t)) that incorporates measurement constraint C(S,A(x,t))= (lambda) ([A]S-X)+((lambda) 0-1)((Sigma) isi -1) using the vector Lagrange multiplier-(lambda) and a- priori Shannon Entropy f(S) = -(Sigma) i si log si as the Contrast function of unknown number of independent sources si. Szu et al. have first solved in 1997 the general Blind Source Separation (BSS) problem for spatial-temporal varying mixing matrix for the real world remote sensing where a large pixel footprint implies the mixing matrix [A(x,t)] necessarily fill with diurnal and seasonal variations. Because the ground truth is difficult to be ascertained in the remote sensing, we have thus illustrated in this paper, each step of the LCNN algorithm for the simulated spatial-temporal varying BSS in speech, music audio mixing. We review and compare LCNN with other popular a-posteriori Maximum Entropy methodologies defined by ANN weight matrix-[W] sigmoid-(sigma) post processing H(Y=(sigma) ([W]X)) by Bell-Sejnowski, Amari and Oja (BSAO) called Independent Component Analysis (ICA). Both are mirror symmetric of the MaxEnt methodologies and work for a constant unknown mixing matrix [A], but the major difference is whether the ensemble average is taken at neighborhood pixel data X's in BASO or at the a priori sources S variables in LCNN that dictates which method works for spatial-temporal varying [A(x,t)] that would not allow the neighborhood pixel average. We expected the success of sharper de-mixing by the LCNN method in terms of a controlled ground truth experiment in the simulation of variant mixture of two music of similar Kurtosis (15 seconds composed of Saint-Saens Swan and Rachmaninov cello concerto).
Feasibility of ultraviolet-light-emitting diodes as an alternative light source for photocatalysis.

PubMed

Levine, Lanfang H; Richards, Jeffrey T; Coutts, Janelle L; Soler, Robert; Maxik, Fred; Wheeler, Raymond M

2011-09-01

The objective of this study was to determine whether ultraviolet-light-emitting diodes (UV-LEDs) could serve as an efficient photon source for heterogeneous photocatalytic oxidation (PCO). An LED module consisting of 12 high-power UV-A (lambda max = 365 nm) LEDs was designed to be interchangeable with a UV-A fluorescent black light blue (BLB) lamp for a bench scale annular reactor packed with silica-titania composite (STC) pellets. Lighting and thermal properties of the module were characterized to assess its uniformity and total irradiance. A forward current (I(F)) of 100 mA delivered an average irradiance of 4.0 mW cm(-2) at a distance of 8 mm, which is equivalent to the maximum output of the BLB, but the irradiance of the LED module was less uniform than that of the BLB. The LED and BLB reactors were tested for the oxidization of ethanol (50 ppm(v)) in a continuous-flow-through mode with 0.94 sec residence time. At the same average irradiance, the UV-A LED reactor resulted in a lower CO2 production rate (19.8 vs. 28.6 nmol L(-1) s(-1)), lower ethanol removal (80% vs. 91%), and lower mineralization efficiency (28% vs. 44%) than the UV-A BLB reactor. Ethanol mineralization was enhanced with the increase of the irradiance at the catalyst surface. This result suggests that reduced ethanol mineralization in the LED reactor relative to the BLB reactor at the same average irradiance could be attributed to the nonuniform irradiance over the photocatalyst, that is, a portion of the catalyst was exposed to less than the average irradiance. The potential of UV-A LEDs may be fully realized by optimizing the light distribution over the catalyst and utilizing their instantaneous "on" and "off" feature for periodic irradiation. Nevertheless, our results also showed that the current UV-A LED module had the same wall plug efficiency (WPE) of 13% as that of the UV-A BLB, demonstrating that UV-A LEDs are a viable photon source both in terms of WPE and PCO efficiency.
Chimeric Anti-Human Podoplanin Antibody NZ-12 of Lambda Light Chain Exerts Higher Antibody-Dependent Cellular Cytotoxicity and Complement-Dependent Cytotoxicity Compared with NZ-8 of Kappa Light Chain.

PubMed

Kaneko, Mika K; Abe, Shinji; Ogasawara, Satoshi; Fujii, Yuki; Yamada, Shinji; Murata, Takeshi; Uchida, Hiroaki; Tahara, Hideaki; Nishioka, Yasuhiko; Kato, Yukinari

2017-02-01

Podoplanin (PDPN), a type I transmembrane 36-kDa glycoprotein, is expressed not only in normal cells, such as renal epithelial cells (podocytes), lymphatic endothelial cells, and pulmonary type I alveolar cells, but also in cancer cells, including brain tumors and lung squamous cell carcinomas. Podoplanin activates platelet aggregation by binding to C-type lectin-like receptor-2 (CLEC-2) on platelets, and the podoplanin/CLEC-2 interaction facilitates blood/lymphatic vessel separation. We previously produced neutralizing anti-human podoplanin monoclonal antibody (mAb), clone NZ-1 (rat IgG 2a , lambda), which neutralizes the podoplanin/CLEC-2 interaction and inhibits platelet aggregation and cancer metastasis. Human-rat chimeric antibody, NZ-8, was previously developed using variable regions of NZ-1 and human constant regions of heavy chain (IgG 1 ) and light chain (kappa chain). Although NZ-8 showed high antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against human podoplanin-expressing cancer cells, the binding affinity of NZ-8 was lower than that of NZ-1. Herein, we produced a novel human-rat chimeric antibody, NZ-12, the constant regions of which consist of IgG 1 heavy chain and lambda light chain. Using flow cytometry, we demonstrated that the binding affinity of NZ-12 was much higher than that of NZ-8. Furthermore, ADCC and CDC activities of NZ-12 were significantly increased against glioblastoma cell lines (LN319 and D397) and lung cancer cell line (PC-10). These results suggested that NZ-12 could become a promising therapeutic antibody against podoplanin-expressing brain tumors and lung cancers.
Comparison of laser in situ keratomileusis flaps created by 2 femtosecond lasers.

PubMed

Zheng, Yan; Zhou, Yuehua; Zhang, Jing; Liu, Qian; Zhai, Changbin; Wang, Yonghua

2015-03-01

To compare flap morphology created by the WaveLight FS200 femtosecond laser and the VisuMax femtosecond laser, assessing the uniformity, accuracy, and predictability of flap creation. A total of 400 eyes had corneal flaps created with the WaveLight FS200 femtosecond laser (200 eyes) or the VisuMax femtosecond laser (200 eyes). The desired flap thickness was 110 μm. At 1 week postoperatively, all eyes were evaluated with RTVue Fourier-domain optical coherence tomography. Dimensions of the flaps were tested for their regularity, uniformity, accuracy, and predictability comparison. One week after surgery, the central flap thickness and the mean flap thickness of the FS200 group were 105.4 ± 3.4 μm and 105.7 ± 2.6 μm, respectively. They were both thinner than those of the VisuMax group, which were 110.8 ± 3.9 μm and 111.3 ± 2.3 μm, respectively. The mean deviation between the achieved and attempted flap thickness of the FS200 group (5.2 ± 1.9 μm) was greater than that of the VisuMax group (3.2 ± 1.8 μm). Flap thickness measurements at 36 points in both groups were close to the intended thickness. Morphology of the flaps in the 0-, 45-, 90-, and 135-degree lines created by the FS200 femtosecond laser and VisuMax femtosecond laser were uniform and regular. Flap dimensions created by the WaveLight FS200 femtosecond laser and VisuMax femtosecond laser were uniform and regular. Although the flap thickness created by the FS200 was less than that created by the VisuMax, measurements of both femtosecond lasers were close to the intended thickness.
In situ measurement of inelastic light scattering in natural waters

NASA Astrophysics Data System (ADS)

Hu, Chuanmin

Variation in the shape of solar absorption (Fraunhofer) lines are used to study the inelastic scattering in natural waters. In addition, oxygen absorption lines near 689nm are used to study the solar stimulated chlorophyll fluorescence. The prototype Oceanic Fraunhofer Line Discriminator (OFLD) has been further developed and improved by using a well protected fiber optic - wire conductor cable and underwater electronic housing. A Monte-Carlo code and a simple code have been modified to simulate the Raman scattering, DOM fluorescence and chlorophyll fluorescence. A series of in situ measurements have been conducted in clear ocean waters in the Florida Straits, in the turbid waters of Florida Bay, and in the vicinity of a coral reef in the Dry Tortugas. By comparing the reduced data with the model simulation results, the Raman scattering coefficient, b r with an excitation wavelength at 488nm, has been verified to be 2.6 × 10-4m-1 (Marshall and Smith, 1990), as opposed to 14.4 × 10- 4m-1 (Slusher and Derr, 1975). The wavelength dependence of b r cannot be accurately determined from the data set as the reported values (λ m-4 to λ m- 5) have an insignificant effect in the natural underwater light field. Generally, in clear water, the percentage of inelastic scattered light in the total light field at /lambda < 510nm is negligible for the whole water column, and this percentage increases with depth at /lambda > 510nm. At low concentrations (a y(/lambda = 380nm) less than 0.1m-1), DOM fluorescence plays a small role in the inelastic light field. However, chlorophyll fluorescence is much stronger than Raman scattering at 685nm. In shallow waters where a sea bottom affects the ambient light field, inelastic light is negligible for the whole visible band. Since Raman scattering is now well characterized, the new OFLD can be used to measure the solar stimulated in situ fluorescence. As a result, the fluorescence signals of various bottom surfaces, from coral to macrophytes, have been measured and have been found to vary with time possibly due to nonphotochemical quenching and photoinhibition.
Phase shifting interferometer

DOEpatents

Sommargren, Gary E.

1999-01-01

An interferometer which has the capability of measuring optical elements and systems with an accuracy of .lambda./1000 where .lambda. is the wavelength of visible light. Whereas current interferometers employ a reference surface, which inherently limits the accuracy of the measurement to about .lambda./50, this interferometer uses an essentially perfect spherical reference wavefront generated by the fundamental process of diffraction. Whereas current interferometers illuminate the optic to be tested with an aberrated wavefront which also limits the accuracy of the measurement, this interferometer uses an essentially perfect spherical measurement wavefront generated by the fundamental process of diffraction. This interferometer is adjustable to give unity fringe visibility, which maximizes the signal-to-noise, and has the means to introduce a controlled prescribed relative phase shift between the reference wavefront and the wavefront from the optics under test, which permits analysis of the interference fringe pattern using standard phase extraction algorithms.
Phase shifting interferometer

DOEpatents

Sommargren, G.E.

1999-08-03

An interferometer is disclosed which has the capability of measuring optical elements and systems with an accuracy of {lambda}/1000 where {lambda} is the wavelength of visible light. Whereas current interferometers employ a reference surface, which inherently limits the accuracy of the measurement to about {lambda}/50, this interferometer uses an essentially perfect spherical reference wavefront generated by the fundamental process of diffraction. Whereas current interferometers illuminate the optic to be tested with an aberrated wavefront which also limits the accuracy of the measurement, this interferometer uses an essentially perfect spherical measurement wavefront generated by the fundamental process of diffraction. This interferometer is adjustable to give unity fringe visibility, which maximizes the signal-to-noise, and has the means to introduce a controlled prescribed relative phase shift between the reference wavefront and the wavefront from the optics under test, which permits analysis of the interference fringe pattern using standard phase extraction algorithms. 11 figs.
Fibrillary glomerulonephritis associated with monoclonal gammopathy of undetermined significance showing lambda-type Bence Jones protein.

PubMed

Nagao, Tomoaki; Okura, Takafumi; Miyoshi, Ken-Ichi; Watanabe, Sanae; Manabe, Seiko; Kurata, Mie; Irita, Jun; Fukuoka, Tomikazu; Higaki, Jitsuo

2005-09-01

A 79-year-old woman was admitted to our hospital because of leg edema due to a nephrotic syndrome. Urinary and serum immunoelectrophoresis showed positive for the lambda type of Bence Jones protein. A bone marrow aspiration test revealed mild plasmacytosis (6.4% of the total cells). These findings confirmed her diagnosis of monoclonal gammopathy of undetermined significance (MGUS). Her renal biopsy specimen revealed mild mesangial cell proliferation and an increase in the mesangial matrix. Immunofluorescence studies showed positive staining for IgG, IgA, C3, and kappa and lambda light chains in the capillary wall and mesangium area. Electron microscopy showed that the electron deposits in the thickened basement membrane were formed by randomly arranged 16- to 18-nm nonbranching fibrils. A Congo red stain for amyloid was negative. These findings corresponded with the diagnosis of fibrillary glomerulonephritis. Therefore, this case showed a rare combination of fibrillary glomerulonephritis and MGUS.
Lambda light chain revision in the human intestinal IgA response.

PubMed

Su, Wen; Gordon, John N; Barone, Francesca; Boursier, Laurent; Turnbull, Wayne; Mendis, Surangi; Dunn-Walters, Deborah K; Spencer, Jo

2008-07-15

Revision of Ab L chains by secondary rearrangement in mature B cells has the potential to change the specific target of the immune response. In this study, we show for the first time that L chain revision is normal and widespread in the largest Ab producing population in man: intestinal IgA plasma cells (PC). Biases in the productive and non-productive repertoire of lambda L chains, identification of the circular products of rearrangement that have the characteristic biases of revision, and identification of RAG genes and protein all reflect revision during normal intestinal IgA PC development. We saw no evidence of IgH revision, probably due to inappropriately orientated recombination signal sequences, and little evidence of kappa-chain revision, probably due to locus inactivation by the kappa-deleting element. We propose that the lambda L chain locus is available and a principal modifier and diversifier of Ab specificity in intestinal IgA PCs.
Chromosomal locations of mouse immunoglobulin genes.

PubMed Central

Valbuena, O; Marcu, K B; Croce, C M; Huebner, K; Weigert, M; Perry, R P

1978-01-01

The chromosomal locations of the structural genes coding for the constant portions of mouse heavy (H) and light chain immunoglobulins were studied by molecular hybridization techniques. Complementary DNA probes containing the constant-region sequences of kappa and lambdaI light chain and alpha, gamma2b, and mu heavy chain mRNAs were annealed to a large excess of DNA from a series of eight mouse-human hybrid cell lines that are deficient for various mouse chromosomes. The lines were scored as positive when a high proportion of a probe annealed and negative when an insignificant proportion annealed. Some lines were clearly negative for H and lambda and clearly positive for kappa. Others were positive or intermediate for lambda, positive for kappa and negative for H. Still others, including a line that was selected for the absence of the mouse X chromosome, were positive for all immunoglobulin species. These results demonstrate that the Clambda, Ckappa, and CH genes are located on different autosomes in the mouse. In contrast, the three heavy-chain families exhibited consistently uniform hybridization results, suggesting that the genes for Calpha, Cgamma, and Cmu are located on the same chromosome. A comparison of karyotypic data with hybridization data has limited the possible locations of the Ig genes to only a few chromosomes. PMID:96442

Immunoglobulin derived depositions in the nervous system: novel mass spectrometry application for protein characterization in formalin-fixed tissues.

PubMed

Rodriguez, Fausto J; Gamez, Jeffrey D; Vrana, Julie A; Theis, Jason D; Giannini, Caterina; Scheithauer, Bernd W; Parisi, Joseph E; Lucchinetti, Claudia F; Pendlebury, William W; Bergen, H Robert; Dogan, Ahmet

2008-10-01

Proteinaceous deposits are occasionally encountered in surgically obtained biopsies of the nervous system. Some of these are amyloidomas, although the precise nature of other cases remains uncertain. We studied 13 cases of proteinaceous aggregates in clinical specimens of the nervous system. Proteins contained within laser microdissected areas of interest were identified from tryptic peptide sequences by liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS). Immunohistochemical studies for immunoglobulin heavy and light chains and amyloidogenic proteins were performed in all cases. Histologically, the cases were classified into three groups: 'proteinaceous deposit not otherwise specified' (PDNOS) (n=6), amyloidoma (n=5), or 'intracellular crystals' (n=2). LC-MS/MS demonstrated the presence of lambda, but not kappa, light chain as well as serum amyloid P in all amyloidomas. lambda-Light-chain immunostaining was noted in amyloid (n=5), although demonstrable monotypic lymphoplasmacytic cells were seen in only one case. Conversely, in PDNOS kappa, but not lambda, was evident in five cases, both light chains being present in a single case. In three cases of PDNOS, a low-grade B-cell lymphoma consistent with marginal zone lymphoma was present in the brain specimen (n=2) or spleen (n=1). Lastly, in the 'intracellular crystals' group, the crystals were present within CD68+ macrophages in one case wherein kappa-light chain was found by LC-MS/MS only; the pathology was consistent with crystal-storing histiocytosis. In the second case, the crystals contained immunoglobulin G within CD138+ plasma cells. Our results show that proteinaceous deposits in the nervous system contain immunoglobulin components and LC-MS/MS accurately identifies the content of these deposits in clinical biopsy specimens. LC-MS/MS represents a novel application for characterization of these deposits and is of diagnostic utility in addition to standard immunohistochemical analyses.
Study of. lambda. parameters and crossover phenomena in SU(N) x SU(N) sigma models in two dimensions

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

Shigemitsu, J; Kogut, J B

1981-01-01

The spin system analogues of recent studies of the string tension and ..lambda.. parameters of SU(N) gauge theories in 4 dimensions are carried out for the SU(N) x SU(N) and O(N) models in 2 dimensions. The relations between the ..lambda.. parameters of both the Euclidean and Hamiltonian formulation of the lattice models and the ..lambda.. parameter of the continuum models are obtained. The one loop finite renormalization of the speed of light in the lattice Hamiltonian formulations of the O(N) and SU(N) x SU(N) models is calculated. Strong coupling calculations of the mass gaps of these spin models are donemore » for all N and the constants of proportionality between the gap and the ..lambda.. parameter of the continuum models are obtained. These results are contrasted with similar calculations for the SU(N) gauge models in 3+1 dimensions. Identifying suitable coupling constants for discussing the N ..-->.. infinity limits, the numerical results suggest that the crossover from weak to strong coupling in the lattice O(N) models becomes less abrupt as N increases while the crossover for the SU(N) x SU(N) models becomes more abrupt. The crossover in SU(N) gauge theories also becomes more abrupt with increasing N, however, at an even greater rate than in the SU(N) x SU(N) spin models.« less
[Modeling asthma evolution by a multi-state model].

PubMed

Boudemaghe, T; Daurès, J P

2000-06-01

There are many scores for the evaluation of asthma. However, most do not take into account the evolutionary aspects of this illness. We propose a model for the clinical course of asthma by a homogeneous Markov model process based on data provided by the A.R.I.A. (Association de Recherche en Intelligence Artificielle dans le cadre de l'asthme et des maladies respiratoires). The criterion used is the activity of the illness during the month before consultation. The activity is divided into three levels: light (state 1), mild (state 2) and severe (state 3). The model allows the evaluation of the strength of transition between states. We found that strong intensities were implicated towards state 2 (lambda(12) and lambda(32)), less towards state 1 (lambda(21) and lambda(31)), and minimum towards state 3 (lambda(23)). This results in an equilibrium distribution essentially divided between state 1 and 2 (44.6% and 51.0% respectively) with a small proportion in state 3 (4.4%). In the future, the increasing amount of available data should permit the introduction of covariables, the distinction of subgroups and the implementation of clinical studies. The interest of this model falls within the domain of the quantification of the illness as well as the representation allowed thereof, while offering a formal framework for the clinical notion of time and evolution.
Structural robustness with suboptimal responses for linear state space model

NASA Technical Reports Server (NTRS)

Keel, L. H.; Lim, Kyong B.; Juang, Jer-Nan

1989-01-01

A relationship between the closed-loop eigenvalues and the amount of perturbations in the open-loop matrix is addressed in the context of performance robustness. If the allowable perturbation ranges of elements of the open-loop matrix A and the desired tolerance of the closed-loop eigenvalues are given such that max(j) of the absolute value of Delta-lambda(j) (A+BF) should be less than some prescribed value, what is a state feedback controller F which satisfies the closed-loop eigenvalue perturbation-tolerance requirement for a class of given perturbation in A? The paper gives an algorithm to design such a controller. Numerical examples are included for illustration.
Laser action benzimidazoles in various aggregate states

NASA Astrophysics Data System (ADS)

Gruzinskii, V. V.; Degtiarenko, K. M.; Shalaev, V. K.; Kopylova, T. N.; Verkhovskii, V. S.; Tarasenko, V. F.; Melchenko, S. V.

1983-04-01

Lasing has been obtained in solutions of benzimidazole (Bi) derivatives: 2-phenyl-Bi (with the band maximum lambda-r-max = 341-347 nm), 2-n-tolyl-Bi (344 nm), and 2-(4'-biphenilyl) Bi (366-374 nm). It is found that compounds of this class provide a basis for laser radiation covering a wide region of the spectrum. Lasing has been obtained on the vapors of 2-(4'-biphenilyl) Bi (361.2 nm) and 2-(n-tolyl) Bi (336.5 nm) with a pentane stabilizer of the excited states. High volatility, photostability, and lasing in wide ranges of concentration determine the efficiency of using this new class of compounds (chain arylbenzimidazoles) in lasers using the vapors of complex molecules.
Determination of molecular weight of membrane proteins by the use of low-angle laser light scattering combined with high-performance gel chromatography in the presence of a non-ionic surfactant.

PubMed

Maezawa, S; Hayashi, Y; Nakae, T; Ishii, J; Kameyama, K; Takagi, T

1983-09-28

An assessment study was carried out to evaluate the performance of the low-angle laser light scattering technique combined with high-performance gel chromatography in the presence of a nonionic surfactant, octaethyleneglycol n-dodecyl ether, precision differential refractometry and ultraviolet photometry. It was found that the combined technique is highly promising as a method for the determination of the molecular weight of a membrane protein solubilized by the surfactant. For trial, molecular weights of the following membrane proteins of Escherichia coli, both solubilized in oligomeric forms, were measured; porin that forms the transmembrane diffusion pore in the outer membrane, and lambda-receptor protein that facilitates the diffusion of maltose-maltodextrins across the outer membrane. The result obtained indicates that both porin and lambda-receptor protein exist as trimers in the surfactant solution.
Plant photomorphogenesis and canopy growth

NASA Technical Reports Server (NTRS)

Ballare, Carlos L.; Scopel, Ana L.

1994-01-01

An important motivation for studying photomorphogenesis is to understand the relationships among plant photophysiology in canopies, canopy productivity, and agronomic yield. This understanding is essential to optimize lighting systems used for plant farming in controlled environments (CE) and for the design of genetically engineered crop strains with altered photoresponses. This article provides an overview of some basic principles of plant photomorphogenesis in canopies and discusses their implications for (1) scaling up information on plant photophysiology from individual plants in CE to whole canopies in the field, and (2) designing lighting conditions to increase plant productivity in CE used for agronomic purposes (e.g. space farming in CE Life Support Systems). We concentrate on the visible (lambda between 400 and 700 nm) and far-infrared (FR; lambda greater than 700 nm) spectral regions, since the ultraviolet (UV; 280 to 400 nm) is covered by other authors in this volume.
Plant photomorphogenesis and canopy growth

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

Ballare, C.L.; Scopel, A.L.

1994-12-31

An important motivation for studying photomorphogenesis is to understand the relationships among plant photophysiology in canopies, canopy productivity, and agronomic yield. This understanding is essential to optimize lighting systems used for plant farming in controlled environments (CE) and for the design of genetically engineered crop strains with altered photoresponses. This article provides an overview of some basic principles of plant photomorphogenesis in canopies and discusses their implications for (1) scaling up information on plant photophysiology from individual plants in CE to whole canopies in the field, and (2), designing lighting conditions to increase plant productivity in CE used for agronomicmore » purposes [e.g. space farming in CE Life-Support-Systems]. We concentrate on the visible ({lambda} between 400 and 700 nm) and far red (FR; {lambda} > 700 nm) spectral regions, since the ultraviolet (UV; 280 to 400 nm) is covered by other authors in this volume.« less
Cybernetic group method of data handling (GMDH) statistical learning for hyperspectral remote sensing inverse problems in coastal ocean optics

NASA Astrophysics Data System (ADS)

Filippi, Anthony Matthew

For complex systems, sufficient a priori knowledge is often lacking about the mathematical or empirical relationship between cause and effect or between inputs and outputs of a given system. Automated machine learning may offer a useful solution in such cases. Coastal marine optical environments represent such a case, as the optical remote sensing inverse problem remains largely unsolved. A self-organizing, cybernetic mathematical modeling approach known as the group method of data handling (GMDH), a type of statistical learning network (SLN), was used to generate explicit spectral inversion models for optically shallow coastal waters. Optically shallow water light fields represent a particularly difficult challenge in oceanographic remote sensing. Several algorithm-input data treatment combinations were utilized in multiple experiments to automatically generate inverse solutions for various inherent optical property (IOP), bottom optical property (BOP), constituent concentration, and bottom depth estimations. The objective was to identify the optimal remote-sensing reflectance Rrs(lambda) inversion algorithm. The GMDH also has the potential of inductive discovery of physical hydro-optical laws. Simulated data were used to develop generalized, quasi-universal relationships. The Hydrolight numerical forward model, based on radiative transfer theory, was used to compute simulated above-water remote-sensing reflectance Rrs(lambda) psuedodata, matching the spectral channels and resolution of the experimental Naval Research Laboratory Ocean PHILLS (Portable Hyperspectral Imager for Low-Light Spectroscopy) sensor. The input-output pairs were for GMDH and artificial neural network (ANN) model development, the latter of which was used as a baseline, or control, algorithm. Both types of models were applied to in situ and aircraft data. Also, in situ spectroradiometer-derived Rrs(lambda) were used as input to an optimization-based inversion procedure. Target variables included bottom depth z b, chlorophyll a concentration [chl- a], spectral bottom irradiance reflectance Rb(lambda), and spectral total absorption a(lambda) and spectral total backscattering bb(lambda) coefficients. When applying the cybernetic and neural models to in situ HyperTSRB-derived Rrs, the difference in the means of the absolute error of the inversion estimates for zb was significant (alpha = 0.05). GMDH yielded significantly better zb than the ANN. The ANN model posted a mean absolute error (MAE) of 0.62214 m, compared with 0.55161 m for GMDH.
PARASITIC INTERFERENCE IN LONG BASELINE OPTICAL INTERFEROMETRY: REQUIREMENTS FOR HOT JUPITER-LIKE PLANET DETECTION

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

Matter, A.; Lopez, B.; Lagarde, S.

2009-12-01

The observable quantities in optical interferometry, which are the modulus and the phase of the complex visibility, may be corrupted by parasitic fringes superimposed on the genuine fringe pattern. These fringes are due to an interference phenomenon occurring from stray light effects inside an interferometric instrument. We developed an analytical approach to better understand this phenomenon when stray light causes cross talk between beams. We deduced that the parasitic interference significantly affects the interferometric phase and thus the associated observables including the differential phase and the closure phase. The amount of parasitic flux coupled to the piston between beams appearsmore » to be very influential in this degradation. For instance, considering a point-like source and a piston ranging from lambda/500 to lambda/5 in the L band (lambda = 3.5 mum), a parasitic flux of about 1% of the total flux produces a parasitic phase reaching at most one-third of the intrinsic phase. The piston, which can have different origins (instrumental stability, atmospheric perturbations, etc.), thus amplifies the effect of parasitic interference. According to the specifications of piston correction in space or at ground level (respectively lambda/500 approx 2 nm and lambda/30 approx 100 nm), the detection of hot Jupiter-like planets, one of the most challenging aims for current ground-based interferometers, limits parasitic radiation to about 5% of the incident intensity. This was evaluated by considering different types of hot Jupiter synthetic spectra. Otherwise, if no fringe tracking is used, the detection of a typical hot Jupiter-like system with a solar-like star would admit a maximum level of parasitic intensity of 0.01% for piston errors equal to lambda/15. If the fringe tracking specifications are not precisely observed, it thus appears that the allowed level of parasitic intensity dramatically decreases and may prevent the detection. In parallel, the calibration of the parasitic phase by a reference star, at this accuracy level, seems very difficult. Moreover, since parasitic phase is an object-dependent quantity, the use of a hypothetical phase abacus, directly giving the parasitic phase from a given parasitic flux level, is also impossible. Some instrumental solutions, implemented at the instrument design stage for limiting or preventing this parasitic interference, appear to be crucial and are presented in this paper.« less
Studies of porphyrin-containing specimens using an optical spectrometer connected to a confocal scanning laser microscope.

PubMed

Trepte, O; Rokahr, I; Andersson-Engels, S; Carlsson, K

1994-12-01

A spectrometer has been developed for use with a confocal scanning laser microscope. With this unit, spectral information from a single point or a user-defined region within the microscope specimen can be recorded. A glass prism is used to disperse the spectral components of the recorded light over a linear CCD photodiode array with 256 elements. A regulated cooling unit keeps the detector at 277 K, thereby allowing integration times of up to 60 s. The spectral resolving power, lambda/delta lambda, ranges from 350 at lambda = 400 nm to 100 at lambda = 700 nm. Since the entrance aperture of the spectrometer has the same size as the detector pinhole used during normal confocal scanning, the three-dimensional spatial resolution is equivalent to that of normal confocal scanning. Light from the specimen is deflected to the spectrometer by a solenoid controlled mirror, allowing fast and easy switching between normal confocal scanning and spectrometer readings. With this equipment, studies of rodent liver specimens containing porphyrins have been made. The subcellular localization is of interest for the mechanisms of photodynamic therapy (PDT) of malignant tumours. Spectroscopic detection is necessary to distinguish the porphyrin signal from other fluorescent components in the specimen. Two different substances were administered to the tissue, Photofrin, a haematoporphyrin derivative (HPD) and delta-amino levulinic acid (ALA), a precursor to protoporphyrin IX and haem in the haem cycle. Both are substances under clinical trials for PDT of malignant tumours. Following administration of these compounds to the tissue, the potent photosensitizer and fluorescent compound Photofrin, or protoporphyrin IX, respectively, is accumulated.(ABSTRACT TRUNCATED AT 250 WORDS)
Absorption and Attenuation Coefficients Using the WET Labs ac-s in the Mid-Atlantic Bight: Field Measurements and Data Analysis

NASA Technical Reports Server (NTRS)

Ohi, Nobuaki; Makinen, Carla P.; Mitchell, Richard; Moisan, Tiffany A.

2008-01-01

Ocean color algorithms are based on the parameterization of apparent optical properties as a function of inherent optical properties. WET Labs underwater absorption and attenuation meters (ac-9 and ac-s) measure both the spectral beam attenuation [c (lambda)] and absorption coefficient [a (lambda)]. The ac-s reports in a continuous range of 390-750 nm with a band pass of 4 nm, totaling approximately 83 distinct wavelengths, while the ac-9 reports at 9 wavelengths. We performed the ac-s field measurements at nine stations in the Mid-Atlantic Bight from water calibrations to data analysis. Onboard the ship, the ac-s was calibrated daily using Milli Q-water. Corrections for the in situ temperature and salinity effects on optical properties of water were applied. Corrections for incomplete recovery of the scattered light in the ac-s absorption tube were performed. The fine scale of spectral and vertical distributions of c (lambda) and a (lambda) were described from the ac-s. The significant relationships between a (674) and that of spectrophotometric analysis and chlorophyll a concentration of discrete water samples were observed.
The optical and physiological properties of phytoplankton - base of model for estimation of primary production in the sea from satellite data.

NASA Astrophysics Data System (ADS)

Finenko, Z. Z.; Churilova, T. Ya.

An assessment of the spatial and temporal variation in the photo physiological parameters and chlorophyll-specific absorption coefficients of marine phytoplankton is essential for estimate of global primary production by satellite data. Relationships of photosynthesis rate on light intensity have been used for estimation of two photosynthetic parameters of phytoplankton in the Black Sea: light saturated photosynthesis intensity (Pb/max, mgC mg Chl-1 h-1) and photosynthesis efficiency (alpha/b mgC mg Chl -1 h-1/ W m-2). The results have shown that variability of photosynthetic parameters of surface phytoplankton during the year varied by one order of values: Pb/max - from 1 to 11 mg C mg Chl-1 h-1 and (alpha/b - from 0.04 to 0.35 mg C mg Chl-1 h-1/Wm-2. Temporal dynamics was characterised by increasing of the values from winter to summer and decreasing to the end of the year. The vertical profiles of Pb/max and alpha/b had opposite character of change: values of Pb/max decreased with depth, alpha/b - increased. Photosynthetic parameters changed with depth more significantly at time of stratification, than - without stratification. The influence of temperature, nitrate concentration and light intensity on Pb/max rather evidence, but temperature and optical depth effect on Pb/max more significantly. Depth-dependent variability of photosynthesis efficiency is generally effected of nutrient concentration. Vertical uniformity of maximum quantum yield of photosynthesis (Fm) and spectral mean absorption coefficient of phytoplankton (aph) in euphotic zone were obtained for cold period of year. In summer - Fm increased from surface to bottom of euphotic zone, aph - decrease. Fm and aph values of surface phytoplankton depended on chlorophyll concentration but their changes had opposite direction: Fm - increased and aph - decreased when chlorophyll concentration grew. As a result Pb/max = Z Fm aph Ik T and alpha/b = Z Fm aph T (where Z - a dimensional constant equal to the atomic mass of carbon, Ik - the photon flux density at which photosynthesis rate becomes light saturated, (mol photons m-2 s-1; T - a constant value for transition from seconds by one hour) change in 2-3 times for the range of chlorophyll concentration (0.05-10.0 mg m-3 ). Pb/max and alpha/b have been approximated by one-peaked curve with maximum at 3 mg m -3 Chl a concentration. These relationships could be used for modeling of Pb/max and alpha/b based on surface chlorophyll concentrations from satellite colour images.
Effect of immediate or delayed light activation on curing kinetics and shrinkage stress of dual-cure resin cements.

PubMed

Faria-e-Silva, Andre; Boaro, Leticia; Braga, Roberto; Piva, Evandro; Arias, Vanessa; Martins, Luis

2011-01-01

This study evaluated the effect of light activation (absence, immediate, or delayed) on conversion kinetics and polymerization stress of three commercial dual-cured resin cements (Enforce, RelyX ARC, and Panavia F). Degree of conversion (DC) was monitored for 30 minutes using real-time near–Fourier transform infrared spectroscopy. The cement was mixed, placed on the spectrometer sample holder, and light activated either immediately or after five minutes (delayed light activation). When no light activation was performed, the materials were protected from light exposure (control). DC was evaluated at five and 30 minutes postmixture. Maximum rates of polymerization (Rp(max)) were obtained from the first derivative of the DC vs time curve. Polymerization stress was monitored for 30 minutes in 1-mm-thick specimens inserted between two cylinders attached to a universal testing machine. Data were submitted to analysis of variance/Tukey tests (α=0.05). Immediate light activation promoted the highest DC at five minutes. At 30 minutes, only RelyX ARC did not present a significant difference in DC between activation modes. Enforce and Panavia F presented higher Rp(max) for immediate and delayed light-activation, respectively. RelyX ARC showed similar Rp(max) for all activation modes. The absence of light activation resulted in the lowest stress followed by delayed light activation, while immediate light activation led to the highest values. RelyX ARC showed higher stress than Enforce, while the stress of Panavia F was similar to that of the others. Delayed light activation reduced the polymerization stress of the resin cements tested without jeopardizing DC.
Vibrio azureus emits blue-shifted light via an accessory blue fluorescent protein.

PubMed

Yoshizawa, Susumu; Karatani, Hajime; Wada, Minoru; Kogure, Kazuhiro

2012-04-01

Luminous marine bacteria usually emit bluish-green light with a peak emission wavelength (λ(max) ) at about 490 nm. Some species belonging to the genus Photobacterium are exceptions, producing an accessory blue fluorescent protein (lumazine protein: LumP) that causes a blue shift, from λ(max) ≈ 490 to λ(max) ≈ 476 nm. However, the incidence of blue-shifted light emission or the presence of accessory fluorescent proteins in bacteria of the genus Vibrio has never been reported. From our spectral analysis of light emitted by 16 luminous strains of the genus Vibrio, it was revealed that most strains of Vibrio azureus emit a blue-shifted light with a peak at approximately 472 nm, whereas other Vibrio strains emit light with a peak at around 482 nm. Therefore, we investigated the mechanism underlying this blue shift in V. azureus NBRC 104587(T) . Here, we describe the blue-shifted light emission spectra and the isolation of a blue fluorescent protein. Intracellular protein analyses showed that this strain had a blue fluorescent protein (that we termed VA-BFP), the fluorescent spectrum of which was almost identical to that of the in vivo light emission spectrum of the strain. This result strongly suggested that VA-BFP was responsible for the blue-shifted light emission of V. azureus. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.
Patterns in tropical seagrass photosynthesis in relation to light, depth and habitat

NASA Astrophysics Data System (ADS)

Campbell, Stuart J.; McKenzie, Len J.; Kerville, Simon P.; Bité, Juanita S.

2007-07-01

Seagrass meadows across north-eastern Australia, survive a range of environmental conditions in coastal bays, reefs, estuarine and deepwater habitats through adaptation of a range of structural, morphological and physiological features. The aim of this study was to investigate the influence of spatial features (habitat type, site and depth) and photon flux on the photosynthetic performance of 11 tropical seagrass species. Pulse amplitude modulated (PAM) fluorometry was used to generate rapid light curves from which measures of maximal electron transport rate (ETR max), photosynthetic efficiency ( α), saturating irradiance ( Ek) and effective quantum yield (Δ F/ Fm') were derived. The amount of light absorbed by leaves (absorption factor) was also determined for each population. In intertidal habitats many seagrass species exhibited typical sun-type responses with a close coupling of both ETR max and Ek with photon flux. Photosynthetic performance ranged from minima in Thalassodendron ciliatum to maxima in Syringodium isoetifolium. The absence of a coupling between photosynthetic performance and photon flux in subtidal populations was most likely due to highly variable light climates and possible light attenuation, and hence the photo-biology of estuarine and deepwater seagrasses exhibited photosynthetic responses indicative of light limitation. In contrast seagrass species from shallow reef and coastal habitats for the most part exhibited light saturation characteristics. Of all the variables examined ETR max, Ek and Δ F/ Fm' were most responsive to changing light climates and provide reliable physiological indicators of real-time photosynthetic performance of tropical seagrasses under different light conditions.
Dust in the small Magellanic cloud. 1: Interstellar polarization and extinction data

NASA Technical Reports Server (NTRS)

Magalhaes, A. M.; Rodrigues, C. V.; Coyne, C. V.; Piirola, V.

1996-01-01

The typical extinction curve for the Small Magellanic Cloud (SMC), in contrast to that for the Galaxy, has no bump at 2175 A and has a steeper rise into the far ultraviolet. For the Galaxy the interpretation of the extinction and, therefore, the dust content of the interstellar medium has been greatly assisted by measurements of the wavelength dependence of the polarization. For the SMC no such measurements existed. Therefore, to further elucidate the dust properties in the SMC we have for the first time measured linear polarization with five colors in the optical region of the spectrum for a sample of reddened stars. For two of these stars, for which there were no existing UV spectrophotometric measurements, but for which we measured a relatively large polarization, we have also obtained data from the International Ultraviolet Explorer (IUE) in order to study the extinction. We also attempt to correlate the SMC extinction and polarization data. The main results are: the wavelength of maximum polarization, lambda(sub max), in the SMC is typically smaller than that in the Galaxy; however, AZC 456, which shows the UV extinction bump, has a lambda(sub max) typical of that in the Galaxy, but its polarization curve is narrower and its bump is shifted to shorter wavelengths as compared to the Galaxy; and from an analysis of both the extinction and polarization data it appears that the SMC has typically smaller grains than those in the Galaxy. The absence of the extinction bump in the SMC has generally been thought to imply a lower carbon abundance in the SMC compared to the Galaxy. We interpret our results to mean that te size distribution of the interstellar grains, and not only the carbon abundance, is different in the SMC as compared to the Galaxy. In Paper 2 we present dust model fits to these observations.
Quantitative analysis of substituted N,N-dimethyl-tryptamines in the presence of natural type XII alkaloids.

PubMed

Ivanova, Bojidarka; Spiteller, Michael

2012-10-01

This paper reports the qualitative and quantitative analysis (QA) of mixtures of hallucinogens, N,N-dimethyltryptamine (DMT) (1), 5-methoxy- (la) and 5-hydroxy-N,N-dimethyltryptamine (1b) in the presence of beta-carbolines (indole alkaloids of type XII) ((2), (3) and (5)}. The validated electronic absorption spectroscopic (EAs) protocol achieved a concentration limit of detection (LOD) of 7.2.10(-7) mol/L {concentration limit of quantification (LOQ) of 24.10(-7) mol/L) using bands (lambda max within 260+/-0.23-262+/-0.33 nm. Metrology, including accuracy, measurement repeatability, measurement precision, trueness of measurement, and reproducibility of the measurements are presented using N,N-dimethyltryptamine (DMA) as standard. The analytical quantities of mixtures of alkaloids 4, 6 and 7 are: lambda max 317+/-0.45, 338+/-0.69 and 430+/-0.09 for 4 (LOD, 8.6.10(-7) mol/L; LOQ, 28.66(6), mol/L), as well as 528+/-0.75 nm for 6 and 7 (LOD, 8.2.10(-7) mol/L; LOQ, 27.33(3), mol/L), respectively. The partially validated protocols by high performance liquid chromatography (HPLC), electrospray ionization (ESI), mass spectrometry (MS), both in single and tandem operation (MS/MS) mode, as well as matrix/assisted laser desorption/ionization (MALDI) MS are elaborated. The Raman spectroscopic (RS) protocol for analysis of psychoactive substances, characterized by strong fluorescence RS profile was developed, with the detection limits being discussed. The known synergistic effect leading to increase the psychoactive and hallucinogenic properties and the reported acute poisoning cases from 1-7, make the present study emergent, since as well the current lack of analytical data and the herein metrology obtained contributed to the elaboration of highly selective and precise analytical protocols, which would be of interest in the field of criminal forensic analysis.
Meteor stream activity. 2: Meteor outbursts

NASA Technical Reports Server (NTRS)

Jenniskens, P.

1995-01-01

In the past two centuries, alert amateur and professional meteor astronomers have documented 35 outbursts of 17 individual meteor streams well enough to allow the construction of a homogeneous set of activity curves. These curves add to similar profiles of the annual streams in a previous paper (Paper 1). This paper attempts to define the type and range of phenomena that classify as meteor outbursts from which the following is concluded: Outbursts are associated with the return of the comet to perihelion (near-comet type outbursts), but occur also when the parent comet is far from perihelion and far from the Earth (far-comet type). All outbursts of a given type only, depending on encounter geometry. The activity curves, expressed in terms of Zenith Hourly Rates (ZHR), have a shape that is generally well described by: ZHR = ZHR(sub max) 10(sup(-B (the absolute value of lambda (sub dot in a circle) - lambda (sup max) (sub dot in a circle))). The steepness of the slopes varies from an exponent of B = 7 to B = 220 per degree of solar longitude, with a typical value of B = 30. In addition, most near-comet type outbursts have a broader component underlying the main peak with B approximately 1 - 7.The duration Delta t is approximately 1/B of the main peak is almost independent of location near the comet, while the background component varies considerably in duration and relative intensity from one return to another. The two components in the activity curve are due to two distinct structures in the dust distribution near the parent comet, where the main component can be due to a sheet of dust that emanates from the IRAS dust trail. This brings the total number of distinct structures in meteor streams to four, including the two structures from the annual stream activity in Paper 1.
DNA-psoralen interaction: a single molecule experiment.

PubMed

Rocha, M S; Viana, N B; Mesquita, O N

2004-11-15

By attaching one end of a single lambda-DNA molecule to a microscope coverslip and the other end to a polystyrene microsphere trapped by an optical tweezers, we can study the entropic elasticity of the lambda-DNA by measuring force versus extension as we stretch the molecule. This powerful method permits single molecule studies. We are particularly interested in the effects of the photosensitive drug psoralen on the elasticity of the DNA molecule. We have illuminated the sample with different light sources, studying how the different wavelengths affect the psoralen-DNA linkage. To do this, we measure the persistence length of individual DNA-psoralen complexes.

Tuning of gold nanoclusters sensing applications with bovine serum albumin and bromelain for detection of Hg2+ ion and lambda-cyhalothrin via fluorescence turn-off and on mechanisms.

PubMed

Bhamore, Jigna R; Jha, Sanjay; Basu, Hirakendu; Singhal, Rakesh Kumar; Murthy, Z V P; Kailasa, Suresh Kumar

2018-04-01

Herein, fluorescent gold nanoclusters (Au NCs) were obtained by one-pot synthetic method using bovine serum albumin (BSA) and bromelain as templates. As-synthesized fluorescent Au NCs were stable and showed bright red fluorescence under UV lamp at 365 nm. The fluorescent Au NCs exhibit the emission intensity at 648 nm when excited at 498 nm. Various techniques were used such as spectroscopy (UV-visible, fluorescence, and Fourier-transform infrared), high-resolution transmission electron microscopy, and dynamic light scattering for the characterization of fluorescent Au NCs. The values of I 0 /I at 648 nm are proportional to the concentrations of Hg 2+ ion in the range from 0.00075 to 5.0 μM and of lambda-cyhalothrin in the range from 0.01 to 10 μM with detection limits of 0.0003 and 0.0075 μM for Hg 2+ ion and lambda-cyhalothrin, respectively. The practical application of the probe was successfully demonstrated by analyzing Hg 2+ ion and lambda-cyhalothrin in water samples. In addition, Au NCs used as probes for imaging of Simplicillium fungal cells. These results indicated that the as-synthesized Au NCs have proven to be promising fluorescent material for the sensing of Hg 2+ ion and lambda-cyhalothrin in environmental and for imaging of microorganism cells in biomedical applications.
Radical-induced generation of small silver particles in SPEEK/PVA polymer films and solutions: UV-Vis, EPR, and FT-IR studies.

PubMed

Korchev, A S; Konovalova, T; Cammarata, V; Kispert, L; Slaten, L; Mills, G

2006-01-03

The present study is centered on the processes involved in the photochemical generation of nanometer-sized Ag particles via illumination at 350 nm of aqueous solutions and cross linked films containing sulfonated poly(ether ether ketone) and poly(vinyl alcohol). Optical and electron paramagnetic resonance experiments, including electron nuclear double resonance data, proved conclusively that the photogenerated chromophore exhibiting a band with lambda(max) = 565 nm is an alpha-hydroxy aromatic (ketyl) radical of the polymeric ketone. This reducing species was produced by illumination of either solutions or films, but the radical lifetime extended from minutes in the fluid phase to hours in the solid. Direct evidence is presented that this long-lived chromophore reduces Ag(I), Cu(II), and Au(III) ions in solution. A rate constant of k = 1.4 x 10(3) M(-)(1) s(-)(1) was obtained for the reduction of Ag(+) by the ketyl radical from the post-irradiation formation of Ag crystallites. FTIR results confirmed that the photoprocess yielding polymeric ketyl radicals involves a reaction between the macromolecules. The photochemical oxidation of the polymeric alcohol, as well as the formation of light-absorbing macromolecular products and polyols, indicates that the sulfonated polyketone experienced transformations similar to those encountered during illumination of the benzophenone/2-propanol system.
A Go-type opsin mediates the shadow reflex in the annelid Platynereis dumerilii.

PubMed

Ayers, Thomas; Tsukamoto, Hisao; Gühmann, Martin; Veedin Rajan, Vinoth Babu; Tessmar-Raible, Kristin

2018-04-18

The presence of photoreceptive molecules outside the eye is widespread among animals, yet their functions in the periphery are less well understood. Marine organisms, such as annelid worms, exhibit a 'shadow reflex', a defensive withdrawal behaviour triggered by a decrease in illumination. Herein, we examine the cellular and molecular underpinnings of this response, identifying a role for a photoreceptor molecule of the G o -opsin class in the shadow response of the marine bristle worm Platynereis dumerilii. We found Pdu-Go-opsin1 expression in single specialised cells located in adult Platynereis head and trunk appendages, known as cirri. Using gene knock-out technology and ablation approaches, we show that the presence of Go-opsin1 and the cirri is necessary for the shadow reflex. Consistently, quantification of the shadow reflex reveals a chromatic dependence upon light of approximately 500 nm in wavelength, matching the photoexcitation characteristics of the Platynereis Go-opsin1. However, the loss of Go-opsin1 does not abolish the shadow reflex completely, suggesting the existence of a compensatory mechanism, possibly acting through a ciliary-type opsin, Pdu-c-opsin2, with a Lambda max of approximately 490 nm. We show that a Go-opsin is necessary for the shadow reflex in a marine annelid, describing a functional example for a peripherally expressed photoreceptor, and suggesting that, in different species, distinct opsins contribute to varying degrees to the shadow reflex.
Seed mediated synthesis of highly mono-dispersed gold nanoparticles in the presence of hydroquinone

NASA Astrophysics Data System (ADS)

Kumar, Dhiraj; Mutreja, Isha; Sykes, Peter

2016-09-01

Gold nanoparticles (AuNPs) are being studied for several biomedical applications, including drug delivery, biomedical imaging, contrast agents and tumor targeting. The synthesis of nanoparticles with a narrow size distribution is critical for these applications. We report the synthesis of highly mono-dispersed AuNPs by a seed mediated approach, in the presence of tri-sodium citrate and hydroquinone (HQ). AuNPs with an average size of 18 nm were used for the synthesis of highly mono-dispersed nanocrystals of an average size 40 nm, 60 nm, 80 nm and ˜100 nm; but the protocol is not limited to these sizes. The colloidal gold was subjected to UV-vis absorbance spectroscopy, showing a red shift in lambda max wavelength, peaks at 518.47 nm, 526.37 nm, 535.73 nm, 546.03 nm and 556.50 nm for AuNPs seed (18 nm), 40 nm, 60 nm, 80 nm and ˜100 nm respectively. The analysis was consistent with dynamic light scattering and electron microscopy. Hydrodynamic diameters measured were 17.6 nm, 40.8 nm, 59.8 nm, 74.1 nm, and 91.4 nm (size by dynamic light scattering—volume %); with an average poly dispersity index value of 0.088, suggesting mono-dispersity in the size distribution, which was also confirmed by transmission electron microscopy analysis. The advantage of a seed mediated approach is a multi-step growth of nanoparticle size that enables us to control the number of nanoparticles in the suspension, for size ranging from 24.5 nm to 95.8 nm. In addition, the HQ-based synthesis of colloidal nanocrystals allowed control of the particle size and size distribution by tailoring either the number of seeds, amount of gold precursor or reducing agent (HQ) in the final reaction mixture.
Complementary shifts in photoreceptor spectral tuning unlock the full adaptive potential of ultraviolet vision in birds.

PubMed

Toomey, Matthew B; Lind, Olle; Frederiksen, Rikard; Curley, Robert W; Riedl, Ken M; Wilby, David; Schwartz, Steven J; Witt, Christopher C; Harrison, Earl H; Roberts, Nicholas W; Vorobyev, Misha; McGraw, Kevin J; Cornwall, M Carter; Kelber, Almut; Corbo, Joseph C

2016-07-12

Color vision in birds is mediated by four types of cone photoreceptors whose maximal sensitivities (λmax) are evenly spaced across the light spectrum. In the course of avian evolution, the λmax of the most shortwave-sensitive cone, SWS1, has switched between violet (λmax > 400 nm) and ultraviolet (λmax < 380 nm) multiple times. This shift of the SWS1 opsin is accompanied by a corresponding short-wavelength shift in the spectrally adjacent SWS2 cone. Here, we show that SWS2 cone spectral tuning is mediated by modulating the ratio of two apocarotenoids, galloxanthin and 11’,12’-dihydrogalloxanthin, which act as intracellular spectral filters in this cell type. We propose an enzymatic pathway that mediates the differential production of these apocarotenoids in the avian retina, and we use color vision modeling to demonstrate how correlated evolution of spectral tuning is necessary to achieve even sampling of the light spectrum and thereby maintain near-optimal color discrimination.
Solar cycle dependence of the sun's radius at lambda = 525.0 nm

NASA Technical Reports Server (NTRS)

Ulrich, Roger K.; Bertello, L.

1995-01-01

The Mount Wilson (California) synoptic program of solar magnetic observations scans the solar disk between 1 and 20 times per day. As part of this program, the radius is determined as an average distance between the image center and the point where the intensity in the FeI line at lambda = 525.0 nm drops to 25 percent of its value at the disk's center. The data base of information was analyzed and corrected for effects such as scattered light and atmospheric reflection. The solar variability and the measurement techniques are described. The observation data sets, the corrections made to the data, and the observed variations, are discussed. It is stated that similar spectral lines at lambda = 525.0 nm, which are common in the solar spectrum, probably exhibit similar radius changes. All portions of the sun are weighted equally so that it is concluded that, within spectral lines, the radiating area of the sun is increased at the solar maximum.
Temporal variation of the Jovian H I Lyman-alpha emission /1979-1982/

NASA Technical Reports Server (NTRS)

Skinner, T. E.; Durrance, S. T.; Feldman, P. D.; Moos, H. W.

1983-01-01

Observations of the Jovian H I Lyman-alpha emission have been made with the International Ultraviolet Explorer (IUE) observatory beginning in 1978 December, just before the time of the Voyager encounters, and extending through 1982 January. A nearly constant disk center brightness of about 8.5 kilorayleighs is observed for the central meridian longitude range lambda(III) = 200 to 360 deg and a variable brightness of between 9 and 15 kilorayleighs is found for the range lambda(III) = 50 to 150 deg. These brightness values have persisted throughout the three years of observation, and the hydrogen bulge near lambda(III) = 100 deg appears to be a fixed feature of the Jovian atmosphere. These results indicate that no substantial changes in the Jovian atomic hydrogen concentration or the average atmospheric conditions have taken place between the time immediately preceding the Voyager encounters and the present. The question of Jovian Lyman-alpha variability prior to 1978 is reexamined in the light of the IUE results.
Double addition of diethylamine to biacetylene (in Russian)

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

Trofimov, B.A.; Vavilova, A.N.

1986-03-01

Biacetylene reacts with an excess of diethylamine in dilute solutions of anhydrous acetonitrile, methanol, ethanol, and THF to form the diadduct 1,3-bis(diethyl-amino)-1,3-butadiene (lambda/sub max/ 325 nm). During concentration of the reaction mixture the latter undergoes hydration by the residual amounts of water in the 3-(diethylamino)-2-butenal. The spectral characteristics (UV, IR, PMR) of the intermediate reaction products are given. The kinetics of the stage of addition of the diethylamine and water to the monoadduct, 1-(diethylamino)-1-buten-3-yne, were studied. It was concluded that the addition of the nucleophile to the triple bond during its secondary amination and hydration is facilitated by the concertedmore » transfer of a proton.« less
AP-8 trapped proton environment for solar maximum and solar minimum. [Computer accessible models

NASA Technical Reports Server (NTRS)

Sawyer, D. M.; Vette, J. I.

1976-01-01

Data sets from Ov-3 and Azur indicate a need for improvement in models of the stably trapped proton flux with energies between 0.1 and 400 MeV. Two computer accessible models are described: AP8MAX and AP8MIN. The models are presented in the form of nomographs, B-L plots, R-lambda plots, and equatorial radial profiles. Nomographs of the orbit-integrated fluxes are also discussed. The models are compared with each other, with the data, and with previous AP models. Requirements for future improvements include more complete data coverage and periodic comparisons with new data sets as they become available. The machine-sensible format in which the models are available are described.
Triple Immunoglobulin Gene Knockout Transchromosomic Cattle: Bovine Lambda Cluster Deletion and Its Effect on Fully Human Polyclonal Antibody Production

PubMed Central

Matsushita, Hiroaki; Sano, Akiko; Wu, Hua; Jiao, Jin-an; Kasinathan, Poothappillai; Sullivan, Eddie J.; Wang, Zhongde; Kuroiwa, Yoshimi

2014-01-01

Towards the goal of producing fully human polyclonal antibodies (hpAbs or hIgGs) in transchromosomic (Tc) cattle, we previously reported that Tc cattle carrying a human artificial chromosome (HAC) comprising the entire unrearranged human immunoglobulin (Ig) heavy-chain (hIGH), kappa-chain (hIGK), and lambda-chain (hIGL) germline loci produced physiological levels of hIgGs when both of the bovine immunoglobulin mu heavy-chains, bIGHM and bIGHML1, were homozygously inactivated (bIGHM−/−, bIGHML1−/−; double knockouts or DKO). However, because endogenous bovine immunoglobulin light chain loci are still intact, the light chains are produced both from the hIGK and hIGL genomic loci on the HAC and from the endogenous bovine kappa-chain (bIGK) and lambda-chain (bIGL) genomic loci, resulting in the production of fully hIgGs (both Ig heavy-chains and light-chains are of human origin: hIgG/hIgκ or hIgG/hIgλ) and chimeric hIgGs (Ig heavy-chains are of human origin while the Ig light-chains are of bovine origin: hIgG/bIgκ or hIgG/bIgλ). To improve fully hIgG production in Tc cattle, we here report the deletion of the entire bIGL joining (J) and constant (C) gene cluster (bIGLJ1-IGLC1 to bIGLJ5-IGLC5) by employing Cre/loxP mediated site-specific chromosome recombination and the production of triple knockout (bIGHM−/−, bIGHML1−/− and bIGL−/−; TKO) Tc cattle. We further demonstrate that bIGL cluster deletion greatly improves fully hIgGs production in the sera of TKO Tc cattle, with 51.3% fully hIgGs (hIgG/hIgκ plus hIgG/hIgλ). PMID:24603704
Design, synthesis and photoelectrochemical properties of hexagonal metallomacrocycles based on triphenylamine: [M6(4,4'-bis(2,2':6',2''-terpyridinyl)triphenylamine)6(X)12]; [M = Fe(II), PF6- and Zn(II), BF4-].

PubMed

Hwang, Seok-Ho; Moorefield, Charles N; Wang, Pingshan; Fronczek, Frank R; Courtney, Brandy H; Newkome, George R

2006-08-07

Synthesis of a novel bis(terpyridine) ligand, 4,4'-bis(2,2':6',2''-terpyridinyl)triphenylamine, utilizing triphenylamine, as a specific angle controller, has led to the self-assembly of a unique hexagonal metallomacrocycle family, [Fe6(2)6(PF6)12] and [Zn6(2)6(BF4)12], utilizing terpyridine-metal(II)-terpyridine connectivity. The crystal structure of the novel ligand shows that the angle between the two terpyridinyl moieties is 119.69 degrees , which enabled the formation of the hexagonal-shaped macrocycles. The crystal packing architectures of this starting ligand revealed channels induced by solvent encapsulation. Following complexation of this ligand with transition metals [Fe(II) or Zn(II)] in a one-pot reaction, the resultant structures were characterized by (1)H and (13)C NMR, UV/Vis and mass spectroscopies. The expected metal-to-ligand charge transfer (MLCT; lambda(max) = 582 nm) and emission (lambda(em) = 575 nm) characteristics were exhibited by both [Fe6(2)6(PF6)12] and[Zn6(2)6(BF4)12]. The photoelectrochemical characteristics of these hexagonal metallomacrocycles demonstrate that they can be used as sensitizers in dye-sensitized solar cells.
Spectrophotometric determination of isopropamide iodide and trifluoperazine hydrochloride in presence of trifluoperazine oxidative degradate.

PubMed

Abbas, Samah S; Zaazaa, Hala E; Abdelkawy, M; Abdelrahman, Maha M

2010-04-01

Four sensitive, selective and precise stability indicating methods for the determination of isopropamide iodide (ISO) and trifluoperazine hydrochloride (TPZ) in their binary mixture and in presence of trifluoperazine oxidative degradate (OXD). Method A is a derivative spectrophotometric one, where ISO was determined by first derivative (D(1)) at 226.4 nm while TPZ was determined by second derivative (D(2)) at 270.2 nm. Method B is the first derivative of the ratio spectra (DD(1)) spectrophotometric method, ISO can be determined by measuring the peak amplitude at 227.4 nm using 5 microg mL(-1) of OXD as a divisor, while TPZ can be determined by measuring the peak amplitude at 249.2 and 261.4 nm using 15 microg mL(-1) of ISO as a divisor. Method C is the isoabsorptive spectrophotometric method. This method allows determination of ISO and TPZ in their binary mixture by measuring total concentration of ISO and TPZ at their isoabsorptive point at lambda(229.8) nm (Aiso1) while TPZ concentration alone can be determined at lambda(max) 311.2 nm, then ISO concentration can be determined by subtraction. On the same basis TPZ can be determined in presence of ISO and OXD, where OXD concentration alone was determined by measuring the peak amplitude at lambda(281.6) and lambda(309.4) nm while total concentration of TPZ and OXD was determined at their isoabsorptive points at (Aiso2 = 270.2 nm), (Aiso3 = 310.6 nm) and (Aiso4 = 331.8 nm) then TPZ concentration was determined by subtraction. Method D is the multivariate calibration techniques [the classical least squares (CLS), principal component regression (PCR) and partial least squares (PLS)], using the information contained in the absorption spectra of ISO, TPZ and OXD mixtures. The selectivity of the proposed methods was checked using laboratory prepared mixtures. The proposed methods have been successfully applied to the analysis of ISO and TPZ in pharmaceutical dosage form without interference from other dosage form additives and the results were statistically compared with the reported method.
Characterization and photochemistry of 13-desmethyl bacteriorhodopsin.

PubMed

Gillespie, Nathan B; Ren, Lei; Ramos, Lavoisier; Daniell, Heather; Dews, Deborah; Utzat, Karissa A; Stuart, Jeffrey A; Buck, Charles H; Birge, Robert R

2005-08-25

The photochemistry of the 13-desmethyl (DM) analogue of bacteriorhodopsin (BR) is examined by using spectroscopy, molecular orbital theory, and chromophore extraction followed by conformational analysis. The removal of the 13-methyl group permits the direct photochemical formation of a thermally stable, photochemically reversible state, P1(DM) (lambda(max) = 525 nm), which can be generated efficiently by exciting the resting state, bR(DM) with yellow or red light (lambda > 590 nm). Chromophore extraction analysis reveals that the retinal configuration in P1(DM) is 9-cis, identical to that of the retinal configuration in the native BR P1 state. Fourier transform infrared and Raman experiments on P1(DM) indicate an anti configuration around the C15=N bond, as would be expected of an O-state photoproduct. However, low-temperature spectroscopy and ambient, time-resolved studies indicate that the P1(DM) state forms primarily via thermal relaxation from the L(D)(DM) state. Theoretical studies on the BR binding site show that 13-dm retinal is capable of isomerizing into a 9-cis configuration with minimal steric hindrance from surrounding residues, in contrast to the native chromophore in which surrounding residues significantly obstruct the corresponding motion. Analysis of the photokinetic experiments indicates that the Arrhenius activation energy of the bR(DM) --> P1(DM) transition in 13-dm-BR is less than 0.6 kcal/mol (vs 22 +/-5 kcal/mol measured for the bR --> P (P1 and P2) reaction in 85:15 glycerol:water suspensions of wild type). Consequently, the P1(DM) state in 13-dm-BR can form directly from all-trans, 15-anti intermediates (bR(DM) and O(DM)) or all-trans, 15-syn (K(D)(DM)/L(D)(DM)) intermediates. This study demonstrates that the 13-methyl group, and its interactions with nearby binding site residues, is primarily responsible for channeling one-photon photochemical and thermal reactions and is limited to the all-trans and 13-cis species interconversions in the native protein.
Photoinduced transition to charge-ordered phases from dynamical localization in the metallic phase of α -(BEDT-TTF)2I3

NASA Astrophysics Data System (ADS)

Oya, Koudai; Takahashi, Akira

2018-03-01

From theory, we investigate charge localization induced by higher-frequency off-resonance light-pulse excitation in the metallic phase of α -(BEDT-TTF) 2I3 by numerically solving the time-dependent Schrödinger equation in the quarter-filled extended Hubbard model for the material. Around e a A(max )=1 , where e a A(max ) is the maximum amplitude of the dimensionless vector potential of the pump pulse, the charge distribution is significantly changed by photoexcitation, and the light-pulse-induced collective charge oscillations continue after photoexcitation. Furthermore, the charge dynamics depend strongly on the polarization direction of the pump pulse. These results are consistent with experiment. The magnitudes of the effective transfer integrals are reduced by strong photoexcitation, and this precursory phenomenon for dynamical localization is mainly driven by a photoinduced change in the ratio of the effective transfer integrals between the two strongest bonds. For e a A(max )≳2 , the photoinduced transition to the charge-ordered state, which can be regarded as a light-dressed state, occurs because of dynamical localization. Furthermore, the type of photogenerated charge-ordered state can be controlled by choosing e a A(max ) and the polarization direction.
HairMax LaserComb laser phototherapy device in the treatment of male androgenetic alopecia: A randomized, double-blind, sham device-controlled, multicentre trial.

PubMed

Leavitt, Matt; Charles, Glenn; Heyman, Eugene; Michaels, David

2009-01-01

The use of low levels of visible or near infrared light for reducing pain, inflammation and oedema, promoting healing of wounds, deeper tissue and nerves, and preventing tissue damage has been known for almost 40 years since the invention of lasers. The HairMax LaserComb is a hand-held Class 3R lower level laser therapy device that contains a single laser module that emulates 9 beams at a wavelength of 655 nm (+/-5%). The device uses a technique of parting the user's hair by combs that are attached to the device. This improves delivery of distributed laser light to the scalp. The combs are designed so that each of the teeth on the combs aligns with a laser beam. By aligning the teeth with the laser beams, the hair can be parted and the laser energy delivered to the scalp of the user without obstruction by the individual hairs on the scalp. The primary aim of the study was to assess the safety and effectiveness of the HairMax LaserComb laser phototherapy device in the promotion of hair growth and in the cessation of hair loss in males diagnosed with androgenetic alopecia (AGA). This double-blind, sham device-controlled, multicentre, 26-week trial randomized male patients with Norwood-Hamilton classes IIa-V AGA to treatment with the HairMax LaserComb or the sham device (2 : 1). The sham device used in the study was identical to the active device except that the laser light was replaced by a non-active incandescent light source. Of the 110 patients who completed the study, subjects in the HairMax LaserComb treatment group exhibited a significantly greater increase in mean terminal hair density than subjects in the sham device group (p < 0.0001). Consistent with this evidence for primary effectiveness, significant improvements in overall hair regrowth were demonstrated in terms of patients' subjective assessment (p < 0.015) at 26 weeks over baseline. The HairMax LaserComb was well tolerated with no serious adverse events reported and no statistical difference in adverse effects between the study groups. The results of this study suggest that the HairMax LaserComb is an effective, well tolerated and safe laser phototherapy device for the treatment of AGA in males.
Five-Body Cluster Structure of the Double-{Lambda} Hypernucleus {sub {Lambda}{Lambda}}{sup 11}Be

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

Hiyama, E.; Kamimura, M.; Yamamoto, Y.

2010-05-28

Energy levels of the double {Lambda} hypernucleus, {sub {Lambda}{Lambda}}{sup 11}Be are calculated within the framework of a {alpha}{alpha}n{Lambda}{Lambda} five-body model. Interactions between constituent particles are determined so as to reproduce reasonably the observed low-energy properties of the {alpha}{alpha}, {alpha}{alpha}n nuclei and the existing data for {Lambda}-binding energies of the {alpha}{Lambda}, {alpha}{alpha}{Lambda}, {alpha}n{Lambda}, and {alpha}{alpha}n{Lambda} systems. An effective {Lambda}{Lambda} interaction is constructed so as to reproduce, within the {alpha}{Lambda}{Lambda} three-body model, the B{sub {Lambda}{Lambda}}of {sub {Lambda}{Lambda}}{sup 6}He, which was extracted from the emulsion experiment, the NAGARA event. With no adjustable parameters for the {alpha}{alpha}n{Lambda}{Lambda} system, B{sub {Lambda}{Lambda}}of the ground and boundmore » excited states of {sub {Lambda}{Lambda}}{sup 11}Be are calculated with the Gaussian expansion method. The Hida event, recently observed at KEK-E373 experiment, is interpreted as an observation of the ground state of the {sub {Lambda}{Lambda}}{sup 11}Be.« less
Stability Error Budget for an Aggressive Coronagraph on a 3.8 m Telescope

NASA Technical Reports Server (NTRS)

Shaklan, Stuart B.; Marchen, Luis; Krist, John; Rud, Mayer

2011-01-01

We evaluate in detail the stability requirements for a band-limited coronagraph with an inner working angle as small as 2 lambda/D coupled to an off-axis, 3.8-m diameter telescope. We have updated our methodologies since presenting a stability error budget for the Terrestrial Planet Finder Coronagraph mission that worked at 4 lambda/D and employed an 8th-order mask to reduce aberration sensitives. In the previous work, we determined the tolerances relative to the total light leaking through the coronagraph. Now, we separate the light into a radial component, which is readily separable from a planet signal, and an azimuthal component, which is easily confused with a planet signal. In the current study, throughput considerations require a 4th-order coronagraph. This, combined with the more aggressive working angle, places extraordinarily tight requirements on wavefront stability and opto-mechanical stability. We find that the requirements are driven mainly by coma that leaks around the coronagraph mask and mimics the localized signal of a planet, and pointing errors that scatter light into the background, decreasing SNR. We also show how the requirements would be relaxed if a low-order aberration detection system could be employed.
Isotype analysis of the anti-CENP-B anticentromere autoantibody: evidence for restricted clonality.

PubMed

Eisenberg, R A; Earnshaw, W C; Bordwell, B J; Craven, S Y; Cheek, R; Rothfield, N F

1989-10-01

Utilizing the centromere B fusion protein (CENP-B) and specific, matched monoclonal antiisotype reagents in an enzyme-linked immunosorbent assay, we found that anti-CENP-B autoantibodies were skewed to the IgG1 isotype. The overall kappa:lambda light chain ratio was 2:1, although several individual sera showed a strong predominance of one of the light chains. Isoelectric focusing of light chain-skewed sera showed polyclonal patterns. Our findings are consistent with the anti-CENP-B autoantibody response being a chronic, antigen-driven response.
Method and apparatus for wavefront sensing

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

Bahk, Seung-Whan

A method for performing optical wavefront sensing includes providing an amplitude transmission mask having a light input side, a light output side, and an optical transmission axis passing from the light input side to the light output side. The amplitude transmission mask is characterized by a checkerboard pattern having a square unit cell of size .LAMBDA.. The method also includes directing an incident light field having a wavelengthmore » $$ \\lamda $$ to be incident on the light input side and propagating the incident light field through the amplitude transmission mask. The method further includes producing a plurality of diffracted light fields on the light output side and detecting, at a detector disposed a distance L from the amplitude transmission mask, an interferogram associated with the plurality of diffracted light fields.« less
Study of {Lambda}-{Lambda} oscillation in quantum coherent {Lambda}{Lambda} by using J/{psi}{yields}{Lambda}{Lambda} decay

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

Kang Xianwei; Department of Physics, Henan Normal University, Xinxiang 453007; Li Haibo

2010-03-01

We discuss the possibility of searching for the {Lambda}-{Lambda} oscillations for coherent {Lambda}{Lambda} production in the J/{psi}{yields}{Lambda}{Lambda} decay process. The sensitivity of measurement of {Lambda}-{Lambda} oscillation in the external field at BES-III experiment is considered. These considerations indicate an alternative way to probe the {Delta}B=2 amplitude in addition to neutron oscillation experiments. Both coherent and time-dependent information can be used to extract the {Lambda}-{Lambda} oscillation parameter. With one year's luminosity at BES-III, we can set an upper limit of {delta}m{sub {Lambda}{Lambda}<}10{sup -15} MeV at 90% confidence level, corresponding to about 10{sup -6} s of {Lambda}-{Lambda} oscillation time.

A fiberoptic reflection oximeter.

PubMed

Landsman, M L; Knop, N; Kwant, G; Mook, G A; Zijlstra, W G

1978-03-20

A catheter tip oximeter is described consisting of a cardiac catheter containing optical fibers, and incandescent light source, a light detection unit and a processing unit. Half of the optical fibers guide the light to the blood at the tip of the catheter, the other half the backscattered (reflected) light to the detection unit. The detection unit contains a dichroic mirror, transmitting most of the light with lambda less than 800 nm and reflecting most of the light with lambda greater than 900 nm, thus splitting the light into two beams. These pass through interference filters with nominal wavelengths of 640 and 920 nm respectively, and are focused on silicium barrier layer photocells. The photocell signals are amplified and fed into a divider giving the ratio of measuring (R640) and compensating (R920) photocell output. The relationship between log R640/R920 and oxygen saturation is represented by a slightly curved line. The relation may be linearized by subtracting a constant voltage from the divided output before taking the logarithm. The slope of the calibration line is dependent on the total haemoglobin concentration. Nonetheless an average calibration line can be used between 70 and 100% oxygen saturation. For 78 measurements of pig blood samples in this range (haemoglobin concentration between 96 and 161 g.1(-1)), the standard deviation of the difference between the fiberoptic oximeter and a Radiometer OSM1 oxygen saturation meter was 1.9% saturation, for 152 samples over the entire saturation range the standard deviation of the difference was 3.1% saturation. The influence of the flow velocity of blood on the light reflection depends on wavelength as well as on oxygen saturation. Therefore, complete compensation for the flow effect is not possible by simple means.
Complementary shifts in photoreceptor spectral tuning unlock the full adaptive potential of ultraviolet vision in birds

PubMed Central

Toomey, Matthew B; Lind, Olle; Frederiksen, Rikard; Curley, Robert W; Riedl, Ken M; Wilby, David; Schwartz, Steven J; Witt, Christopher C; Harrison, Earl H; Roberts, Nicholas W; Vorobyev, Misha; McGraw, Kevin J; Cornwall, M Carter; Kelber, Almut; Corbo, Joseph C

2016-01-01

Color vision in birds is mediated by four types of cone photoreceptors whose maximal sensitivities (λmax) are evenly spaced across the light spectrum. In the course of avian evolution, the λmax of the most shortwave-sensitive cone, SWS1, has switched between violet (λmax > 400 nm) and ultraviolet (λmax < 380 nm) multiple times. This shift of the SWS1 opsin is accompanied by a corresponding short-wavelength shift in the spectrally adjacent SWS2 cone. Here, we show that SWS2 cone spectral tuning is mediated by modulating the ratio of two apocarotenoids, galloxanthin and 11’,12’-dihydrogalloxanthin, which act as intracellular spectral filters in this cell type. We propose an enzymatic pathway that mediates the differential production of these apocarotenoids in the avian retina, and we use color vision modeling to demonstrate how correlated evolution of spectral tuning is necessary to achieve even sampling of the light spectrum and thereby maintain near-optimal color discrimination. DOI: http://dx.doi.org/10.7554/eLife.15675.001 PMID:27402384
Shell-model predictions for Lambda Lambda hypernuclei

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

Gal, A.; Millener, D.

2011-06-02

It is shown how the recent shell-model determination of {Lambda}N spin-dependent interaction terms in {Lambda} hypernuclei allows for a reliable deduction of {Lambda}{Lambda} separation energies in {Lambda}{Lambda} hypernuclei across the nuclear p shell. Comparison is made with the available data, highlighting {sub {Lambda}{Lambda}}{sup 11}Be and {sub {Lambda}{Lambda}}{sup 12}Be which have been suggested as possible candidates for the KEK-E373 HIDA event.
Identification of cyanobacteriochromes detecting far-red light

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

Rockwell, Nathan C.; Martin, Shelley S.; Lagarias, J. Clark

The opacity of mammalian tissue to visible light and the strong attenuation of infrared light by water at ≥900 nm have contributed to growing interest in the development of far-red and near-infrared absorbing tools for visualizing and actuating responses within live cells. Here we report the discovery of cyanobacteriochromes (CBCRs) responsive to light in this far-red window. CBCRs are linear tetrapyrrole (bilin)-based light sensors distantly related to plant phytochrome sensors. Our studies reveal far-red (λ max = 725–755 nm)/orange (λ max = 590–600 nm) and far-red/red (λ max = 615–685 nm) photoswitches that are small (<200 amino acids) and canmore » be genetically reconstituted in living cells. Phylogenetic analysis and characterization of additional CBCRs demonstrated that far-red/orange CBCRs evolved after a complex transition from green/red CBCRs known for regulating complementary chromatic acclimation. Incorporation of different bilin chromophores demonstrated that tuning mechanisms responsible for red-shifted chromophore absorption act at the A-, B-, and/ or C-rings, whereas photoisomerization occurs at the D-ring. Two such proteins exhibited detectable fluorescence extending well into the near-infrared region. In conclusion, this work extends the spectral window of CBCRs to the edge of the infrared, raising the possibility of using CBCRs in synthetic biology applications in the far-red region of the spectrum.« less
Identification of cyanobacteriochromes detecting far-red light

DOE PAGES

Rockwell, Nathan C.; Martin, Shelley S.; Lagarias, J. Clark

2016-06-13

The opacity of mammalian tissue to visible light and the strong attenuation of infrared light by water at ≥900 nm have contributed to growing interest in the development of far-red and near-infrared absorbing tools for visualizing and actuating responses within live cells. Here we report the discovery of cyanobacteriochromes (CBCRs) responsive to light in this far-red window. CBCRs are linear tetrapyrrole (bilin)-based light sensors distantly related to plant phytochrome sensors. Our studies reveal far-red (λ max = 725–755 nm)/orange (λ max = 590–600 nm) and far-red/red (λ max = 615–685 nm) photoswitches that are small (<200 amino acids) and canmore » be genetically reconstituted in living cells. Phylogenetic analysis and characterization of additional CBCRs demonstrated that far-red/orange CBCRs evolved after a complex transition from green/red CBCRs known for regulating complementary chromatic acclimation. Incorporation of different bilin chromophores demonstrated that tuning mechanisms responsible for red-shifted chromophore absorption act at the A-, B-, and/ or C-rings, whereas photoisomerization occurs at the D-ring. Two such proteins exhibited detectable fluorescence extending well into the near-infrared region. In conclusion, this work extends the spectral window of CBCRs to the edge of the infrared, raising the possibility of using CBCRs in synthetic biology applications in the far-red region of the spectrum.« less
Rapid determination of chromium(VI) in electroplating waste water by use of a spectrophotometric flow injection system.

PubMed

Yuan, Dong; Fu, Dayou; Wang, Rong; Yuan, Jigang

2008-11-01

A new rapid and sensitive FI method is reported for spectrophotometric determination of trace chromium(VI) in electroplating waste water. The method is based on the reaction of Cr(VI) with sodium diphenylamine sulfonate (DPH) in acidic medium to form a purple complex (lambda(max) = 550 nm). Under the optimized conditions, the calibration curve is linear in the range 0.04-3.8 microg ml(-1) at a sampling rate of 30 h(-1). The detection limit of the method is 0.0217 microg ml(-1), and the relative standard deviation is 1.1% for eight determinations of 2 microg ml(-1) Cr(VI). The proposed method was applied to the determination of chromium in electroplating waste water with satisfactory results.
Determination of hydrolyzable tannins (gallotannins and ellagitannins) after reaction with potassium iodate.

PubMed

Hartzfeld, Paul W; Forkner, Rebecca; Hunter, Mark D; Hagerman, Ann E

2002-03-27

A widely used method for analyzing hydrolyzable tannins afer reaction with KIO(3) has been modified to include a methanolysis step followed by oxidation with KIO(3). In the new method, hydrolyzable tannins (gallotannins and ellagitannins) are reacted at 85 degrees C for 20 h in methanol/sulfuric acid to quantitatively release methyl gallate. Dried plant samples can be methanolyzed under the same conditions to convert hydrolyzable tannins to methyl gallate. Oxidation of the methyl gallate by KIO(3) at pH 5.5, 30 degrees C, forms a chromophore with lambda(max) 525 nm, which is determined spectrophotometrically. The detection limit of the method is 1.5 microg of methyl gallate, and with plant samples, relative standard deviations of less than 3% were obtained.
Isolation, purification and partial characterization of viper venom inhibiting factor from the root extract of the Indian medicinal plant sarsaparilla (Hemidesmus indicus R. Br.).

PubMed

Alam, M I; Auddy, B; Gomes, A

1994-12-01

An organic acid, isolated and purified from the root extract of an Indian medicinal plant sarsaparilla Hemidesmus indicus R. Br, possessed viper venom inhibitory activity. The compound (designated HI-RVIF) was isolated by solvent extraction, silica gel column chromatography and thin layer chromatography, and was homogeneous in nature. The white needle-shaped crystals were soluble in water, methanol and chloroform and had a melting point of 155-158 degrees C and lambda max 260 nm. Spectral analysis confirmed the presence of a benzene ring, methoxy group, and hydroxyl group; the mol. wt of the compound was 168. HI-RVIF significantly antagonized viper venom-induced lethal, haemorrhagic, coagulant and anticoagulant activity in experimental rodents.
The reactions of cytidine and 2'-deoxycytidine with SO4.- revisited. Pulse radiolysis and product studies.

PubMed

Aravindakumar, Charuvila T; Schuchmann, Man Nien; Rao, Balijepalli S; von Sonntag, Justus; von Sonntag, Clemens

2003-01-21

The reactions of SO4.- with 2'-deoxycytidine 1a and cytidine 1b lead to very different intermediates (base radicals with 1a, sugar radicals with 1b). The present study provides spectral and kinetic data for the various intermediates by pulse radiolysis as well as information on final product yields (free cytosine). Taking these and literature data into account allows us to substantiate but also modify in essential aspects the current mechanistic concept (H. Catterall, M. J. Davies and B. C. Gilbert, J. Chem. Soc., Perkin Trans. 2, 1992, 1379). SO4.- radicals have been generated radiolytically in the reaction of peroxodisulfate with the hydrated electron (and the H. atom). In the reaction of SO4.- with 1a (k = 1.6 x 10(9) dm3 mol-1 s-1), a transient (lambda max = 400 nm, shifted to 450 nm at pH 3) is observed. This absorption is due to two intermediates. The major component (lambda max approximately 385 nm) does not react with O2 and has been attributed to an N-centered radical 4a formed upon sulfate release and deprotonation at nitrogen. The minor component, rapidly wiped out by O2, must be due to C-centered OH-adduct radical(s) 6a and/or 7a suggested to be formed by a water-induced nucleophilic replacement. These radicals decay by second-order kinetics. Free cytosine is only formed in low yields (G = 0.14 x 10(-7) mol J-1 upon electron-beam irradiation). In contrast, 1b gives rise to an intermediate absorbing at lambda max = 530 nm (shifted to 600 nm in acid solution) which rapidly decays (k = 6 x 10(4) s-1). In the presence of O2, the decay is much faster (k approximately 1.3 x 10(9) dm3 mol-1 s-1) indicating that this species must be a C-centered radical. This has been attributed to the C(5)-yl radical 8 formed upon the reaction of the C(2')-OH group with the cytidine SO4(.-)-adduct radical 2b. This reaction competes very effectively with the corresponding reaction of water and the release of sulfate and a proton generating the N-centered radical. Upon the decay of 8, sugar radical 11 is formed with the release of cytosine. The latter is formed with a G value of 2.8 x 10(-7) mol J-1 (85% of primary SO4.-) at high dose rates (electron beam irradiation). At low dose rates (gamma-radiolysis) its yield is increased to 7 x 10(-7) mol J-1 due to a chain reaction involving peroxodisulfate and reducing free radicals. Phosphate buffer prevents the formation of the sugar radical at the SO4(.-)-adduct stage by enhancing the rate of sulfate release by deprotonation of 2b and also by speeding up the decay of the C(5)-yl radical into another (base) radical. Cytosine release in cytidine is mechanistically related to strand breakage in poly(C). Literature data on the effect of dioxygen on strand breakage yields in poly(C) induced by SO4.- (suppressed) and upon photoionisation (unaltered) lead us to conclude that in poly(C) and also in the present system free radical cations are not involved to a major extent. This conclusion modifies an essential aspect of the current mechanistic concept.
Time-resolved diffusion tomographic 2D and 3D imaging in highly scattering turbid media

NASA Technical Reports Server (NTRS)

Alfano, Robert R. (Inventor); Cai, Wei (Inventor); Liu, Feng (Inventor); Lax, Melvin (Inventor); Das, Bidyut B. (Inventor)

1999-01-01

A method for imaging objects in highly scattering turbid media. According to one embodiment of the invention, the method involves using a plurality of intersecting source/detectors sets and time-resolving equipment to generate a plurality of time-resolved intensity curves for the diffusive component of light emergent from the medium. For each of the curves, the intensities at a plurality of times are then inputted into the following inverse reconstruction algorithm to form an image of the medium: ##EQU1## wherein W is a matrix relating output at source and detector positions r.sub.s and r.sub.d, at time t, to position r, .LAMBDA. is a regularization matrix, chosen for convenience to be diagonal, but selected in a way related to the ratio of the noise, to fluctuations in the absorption (or diffusion) X.sub.j that we are trying to determine: .LAMBDA..sub.ij =.lambda..sub.j .delta..sub.ij with .lambda..sub.j =/<.DELTA.Xj.DELTA.Xj> Y is the data collected at the detectors, and X.sup.k is the kth iterate toward the desired absoption information. An algorithm, which combines a two dimensional (2D) matrix inversion with a one-dimensional (1D) Fourier transform inversion is used to obtain images of three dimensional hidden objects in turbid scattering media.
Time-resolved diffusion tomographic 2D and 3D imaging in highly scattering turbid media

NASA Technical Reports Server (NTRS)

Alfano, Robert R. (Inventor); Cai, Wei (Inventor); Gayen, Swapan K. (Inventor)

2000-01-01

A method for imaging objects in highly scattering turbid media. According to one embodiment of the invention, the method involves using a plurality of intersecting source/detectors sets and time-resolving equipment to generate a plurality of time-resolved intensity curves for the diffusive component of light emergent from the medium. For each of the curves, the intensities at a plurality of times are then inputted into the following inverse reconstruction algorithm to form an image of the medium: wherein W is a matrix relating output at source and detector positions r.sub.s and r.sub.d, at time t, to position r, .LAMBDA. is a regularization matrix, chosen for convenience to be diagonal, but selected in a way related to the ratio of the noise, to fluctuations in the absorption (or diffusion) X.sub.j that we are trying to determine: .LAMBDA..sub.ij =.lambda..sub.j .delta..sub.ij with .lambda..sub.j =/<.DELTA.Xj.DELTA.Xj> Y is the data collected at the detectors, and X.sup.k is the kth iterate toward the desired absorption information. An algorithm, which combines a two dimensional (2D) matrix inversion with a one-dimensional (1D) Fourier transform inversion is used to obtain images of three dimensional hidden objects in turbid scattering media.
From Ξb→Λbπ to Ξc→Λcπ

DOE PAGES

Gronau, Michael; Rosner, Jonathan L.

2016-04-11

Using a successful framework for describing S-wave hadronic decays of light hyperons induced by a subprocess s -> u((u) over bard), we presented recently a model-independent calculation of the amplitude and branching ratio for Xi(-)(b) -> Lambda(b)pi(-) in agreement with a LHCb measurement. The same quark process contributes to Xi(0)(c) -> Lambda(c)pi(-), while a second term from the subprocess cs -> cd has been related by Voloshin to differences among total decay rates of charmed baryons. We calculate this term and find it to have a magnitude approximately equal to the s -> u((u) over bard) term. We argue formore » a negligible relative phase between these two contributions, potentially due to final state interactions. However, we do not know whether they interfere destructively or constructively. For constructive interference one predicts B(Xi(0)(c) -> Lambda(c)pi(-)) = (1.94 +/- 0.70) x 10(-3) and B(Xi(+)(c) -> Lambda(c)pi(0)) = (3.86 +/- 1.35) x 10(-3). For destructive interference, the respective branching fractions are expected to be less than about 10(-4) and 2 x 10(-4). (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).« less
From Ξb→Λbπ to Ξc→Λcπ

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

Gronau, Michael; Rosner, Jonathan L.

Using a successful framework for describing S-wave hadronic decays of light hyperons induced by a subprocess s -> u((u) over bard), we presented recently a model-independent calculation of the amplitude and branching ratio for Xi(-)(b) -> Lambda(b)pi(-) in agreement with a LHCb measurement. The same quark process contributes to Xi(0)(c) -> Lambda(c)pi(-), while a second term from the subprocess cs -> cd has been related by Voloshin to differences among total decay rates of charmed baryons. We calculate this term and find it to have a magnitude approximately equal to the s -> u((u) over bard) term. We argue formore » a negligible relative phase between these two contributions, potentially due to final state interactions. However, we do not know whether they interfere destructively or constructively. For constructive interference one predicts B(Xi(0)(c) -> Lambda(c)pi(-)) = (1.94 +/- 0.70) x 10(-3) and B(Xi(+)(c) -> Lambda(c)pi(0)) = (3.86 +/- 1.35) x 10(-3). For destructive interference, the respective branching fractions are expected to be less than about 10(-4) and 2 x 10(-4). (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).« less
On the inscription of period and half-period surface relief gratings in azobenzene-functionalized polymers.

PubMed

Sobolewska, Anna; Miniewicz, Andrzej

2008-04-17

Laser-light-induced surface relief grating inscription was carried out in the newly synthesized azobenzene-functionalized poly(amide-imide)s having the same main- and side-chain structures but different substituents in the azobenzene groups. The gratings were inscribed employing the two-wave mixing technique with linearly polarized laser beams. Three different polarization configurations were used: s-s, p-p, and s-p. The relatively deep surface relief gratings of period Lambda were formed for the case of s-s and p-p polarizations, whereas the s-p inscription resulted in the half-period grating (Lambda/2) with the weak surface modulation. The origin of the formation of Lambda/2 structure for s-p configuration results from the interference between zeroth- and first-order beams scattered on the polarization refractive index grating and having the same polarization. On the basis of this idea, we presented the simple kinetic model predicting and modeling the half-period grating formation with its temporal evolution. The proposed model is consistent with the experimental findings.
Observation of Mollow Triplets with Tunable Interactions in Double Lambda Systems of Individual Hole Spins

NASA Astrophysics Data System (ADS)

Lagoudakis, K. G.; Fischer, K. A.; Sarmiento, T.; McMahon, P. L.; Radulaski, M.; Zhang, J. L.; Kelaita, Y.; Dory, C.; Müller, K.; Vučković, J.

2017-01-01

Although individual spins in quantum dots have been studied extensively as qubits, their investigation under strong resonant driving in the scope of accessing Mollow physics is still an open question. Here, we have grown high quality positively charged quantum dots embedded in a planar microcavity that enable enhanced light-matter interactions. Under a strong magnetic field in the Voigt configuration, individual positively charged quantum dots provide a double lambda level structure. Using a combination of above-band and resonant excitation, we observe the formation of Mollow triplets on all optical transitions. We find that when the strong resonant drive power is used to tune the Mollow-triplet lines through each other, we observe anticrossings. We also demonstrate that the interaction that gives rise to the anticrossings can be controlled in strength by tuning the polarization of the resonant laser drive. Quantum-optical modeling of our system fully captures the experimentally observed spectra and provides insight on the complicated level structure that results from the strong driving of the double lambda system.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, B.; Kantowski, R.; Dai, X.

We compute time delays for gravitational lensing in a flat {Lambda} dominated cold dark matter Swiss cheese universe. We assume a primary and secondary pair of light rays are deflected by a single point mass condensation described by a Kottler metric (Schwarzschild with {Lambda}) embedded in an otherwise homogeneous cosmology. We find that the cosmological constant's effect on the difference in arrival times is nonlinear and at most around 0.002% for a large cluster lens; however, we find differences from time delays predicted by conventional linear lensing theory that can reach {approx}4% for these large lenses. The differences in predictedmore » delay times are due to the failure of conventional lensing to incorporate the lensing mass into the mean mass density of the universe.« less
An arena for model building in the Cohen-Glashow very special relativity

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

Sheikh-Jabbari, M. M., E-mail: jabbari@theory.ipm.ac.i; Tureanu, A., E-mail: anca.tureanu@helsinki.f

2010-02-15

The Cohen-Glashow Very Special Relativity (VSR) algebra is defined as the part of the Lorentz algebra which upon addition of CP or T invariance enhances to the full Lorentz group, plus the space-time translations. We show that noncommutative space-time, in particular noncommutative Moyal plane, with light- like noncommutativity provides a robust mathematical setting for quantum field theories which are VSR invariant and hence set the stage for building VSR invariant particle physics models. In our setting the VSR invariant theories are specified with a single deformation parameter, the noncommutativity scale {Lambda}{sub NC}. Preliminary analysis with the available data leads tomore » {Lambda}{sub NC} {>=} 1-10 TeV.« less
Measurement of the forward-backward asymmetry of $$\\Lambda$$ and $$\\bar{\\Lambda}$$ production in $$p \\bar{p}$$ collisions

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

Abazov, Victor Mukhamedovich

Here, we studymore » $$\\Lambda$$ and $$\\bar{\\Lambda}$$ production asymmetries in $$p \\bar{p} \\rightarrow \\Lambda (\\bar{\\Lambda}) X$$, $$p \\bar{p} \\rightarrow J/\\psi \\Lambda (\\bar{\\Lambda}) X$$, and $$p \\bar{p} \\rightarrow \\mu^\\pm \\Lambda (\\bar{\\Lambda}) X$$ events recorded by the D0 detector at the Fermilab Tevatron collider at $$\\sqrt{s} = 1.96$$ TeV. We find an excess of $$\\Lambda$$'s ($$\\bar{\\Lambda}$$'s) produced in the proton (antiproton) direction. This forward-backward asymmetry is measured as a function of rapidity. We confirm that the $$\\bar{\\Lambda}/\\Lambda$$ production ratio, measured by several experiments with various targets and a wide range of energies, is a universal function of "rapidity loss", i.e., the rapidity difference of the beam proton and the lambda.« less
Measurement of the forward-backward asymmetry of $$\\Lambda$$ and $$\\bar{\\Lambda}$$ production in $$p \\bar{p}$$ collisions

DOE PAGES

Abazov, Victor Mukhamedovich

2016-02-09

Here, we studymore » $$\\Lambda$$ and $$\\bar{\\Lambda}$$ production asymmetries in $$p \\bar{p} \\rightarrow \\Lambda (\\bar{\\Lambda}) X$$, $$p \\bar{p} \\rightarrow J/\\psi \\Lambda (\\bar{\\Lambda}) X$$, and $$p \\bar{p} \\rightarrow \\mu^\\pm \\Lambda (\\bar{\\Lambda}) X$$ events recorded by the D0 detector at the Fermilab Tevatron collider at $$\\sqrt{s} = 1.96$$ TeV. We find an excess of $$\\Lambda$$'s ($$\\bar{\\Lambda}$$'s) produced in the proton (antiproton) direction. This forward-backward asymmetry is measured as a function of rapidity. We confirm that the $$\\bar{\\Lambda}/\\Lambda$$ production ratio, measured by several experiments with various targets and a wide range of energies, is a universal function of "rapidity loss", i.e., the rapidity difference of the beam proton and the lambda.« less
Frequency-scanning particle size spectrometer

NASA Technical Reports Server (NTRS)

Fymat, A. L. (Inventor)

1979-01-01

A particle size spectrometer having a fixed field of view within the forward light scattering cone at an angle theta sub s between approximately 100 and 200 minutes of arc (preferably at 150 minutes), a spectral range extending approximately from 0.2 to 4.0 inverse micrometers, and a spectral resolution between about 0.1 and 0.2 inverse micrometers (preferably toward the lower end of this range of spectral resolution), is employed to determine the distribution of particle sizes, independently of the chemical composition of the particles, from measurements of incident light, at each frequency, sigma (=1/lambda), and scattered light, I(sigma).

Quantum scattering studies of spin-orbit effects in the Cl({sup 2}P) + HCl {yields} ClH + Cl({sup 2}P) reaction

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

Schatz, G.C.; McCabe, P.; Connor, J.N.L.

1998-07-01

The authors present quantum scattering calculations for the Cl + HCl {yields} ClH + Cl reaction in which they include the three electronic states that correlate asymptotically to the ground state of Cl({sup 2}P) + HCl(X{sup 1}{Sigma}{sup +}). The potential surfaces and couplings are taken from the recent work of C.S. Maierle, G.C. Schatz, M.S. Gordon, P. McCabe and J.N.L. Connor, J. Chem. Soc. Farad. Trans. (1997). They are based on extensive ab initio calculations for geometries in the vicinity of the lowest energy saddle point, and on an electrostatic expansion (plus empirical dispersion and repulsion) for long range geometriesmore » including the van der Waals wells. Spin-orbit coupling has been included using a spin-orbit coupling parameter {lambda} that is assumed to be independent of nuclear geometry, and Coriolis interactions are incorporated accurately. The scattering calculations use a hyperspherical coordinate coupled channel method in full dimensionality. AJ-shifting approximation is employed to convert cumulative reaction probabilities for total angular momentum quantum number J = 1/2 into state selected and thermal rate coefficients. Two issues have been studied: (a) the influence of the magnitude of {lambda} on the fine-structure resolved cumulative probabilities and rate coefficients (the authors consider {lambda}`s that vary from 0 to {+-}100% of the true Cl value), and (b) the transition state resonance spectrum, and its variation with {lambda} and with other parameters in the calculations. Cl + HCl is a simple hydrogen transfer reaction which serves as a canonical model both for heavy-light-heavy atom reactions, and for the reactions of halogen atoms with closed shell molecules.« less
Positive selection of a duplicated UV-sensitive visual pigment coincides with wing pigment evolution in Heliconius butterflies.

PubMed

Briscoe, Adriana D; Bybee, Seth M; Bernard, Gary D; Yuan, Furong; Sison-Mangus, Marilou P; Reed, Robert D; Warren, Andrew D; Llorente-Bousquets, Jorge; Chiao, Chuan-Chin

2010-02-23

The butterfly Heliconius erato can see from the UV to the red part of the light spectrum with color vision proven from 440 to 640 nm. Its eye is known to contain three visual pigments, rhodopsins, produced by an 11-cis-3-hydroxyretinal chromophore together with long wavelength (LWRh), blue (BRh) and UV (UVRh1) opsins. We now find that H. erato has a second UV opsin mRNA (UVRh2)-a previously undescribed duplication of this gene among Lepidoptera. To investigate its evolutionary origin, we screened eye cDNAs from 14 butterfly species in the subfamily Heliconiinae and found both copies only among Heliconius. Phylogeny-based tests of selection indicate positive selection of UVRh2 following duplication, and some of the positively selected sites correspond to vertebrate visual pigment spectral tuning residues. Epi-microspectrophotometry reveals two UV-absorbing rhodopsins in the H. erato eye with lambda(max) = 355 nm and 398 nm. Along with the additional UV opsin, Heliconius have also evolved 3-hydroxy-DL-kynurenine (3-OHK)-based yellow wing pigments not found in close relatives. Visual models of how butterflies perceive wing color variation indicate this has resulted in an expansion of the number of distinguishable yellow colors on Heliconius wings. Functional diversification of the UV-sensitive visual pigments may help explain why the yellow wing pigments of Heliconius are so colorful in the UV range compared to the yellow pigments of close relatives lacking the UV opsin duplicate.
Demonstration of a sensory rhodopsin in eubacteria.

PubMed

Jung, Kwang-Hwan; Trivedi, Vishwa D; Spudich, John L

2003-03-01

We report the first sensory rhodopsin observed in the eubacterial domain, a green light-activated photoreceptor in Anabaena (Nostoc) sp. PCC7120, a freshwater cyanobacterium. The gene encoding the membrane opsin protein of 261 residues (26 kDa) and a smaller gene encoding a soluble protein of 125 residues (14 kDa) are under the same promoter in a single operon. The opsin expressed heterologously in Escherichia coli membranes bound all-trans retinal to form a pink pigment (lambda max 543 nm) with a photochemical reaction cycle of 110 ms half-life (pH 6.8, 18 degrees C). Co-expression with the 14 kDa protein increased the rate of the photocycle, indicating physical interaction with the membrane-embedded rhodopsin, which we confirmed in vitro by affinity enrichment chromatography and Biacore interaction. The pigment lacks the proton donor carboxylate residue in helix C conserved in known retinylidene proton pumps and did not exhibit detectable proton ejection activity. We detected retinal binding to the protein in Anabaena membranes by SDS-PAGE and autofluorography of 3H-labelled all-trans retinal of reduced membranes from the organism. We conclude that Anabaena rhodopsin functions as a photosensory receptor in its natural environment, and suggest that the soluble 14 kDa protein transduces a signal from the receptor. Therefore, unlike the archaeal sensory rhodopsins, which transmit signals by transmembrane helix-helix interactions with membrane-embedded transducers, the Anabaena sensory rhodopsin may signal through a soluble cytoplasmic protein, analogous to higher animal visual pigments.
Cosmic microwave background anisotropies in cold dark matter models with cosmological constant: The intermediate versus large angular scales

NASA Technical Reports Server (NTRS)

Stompor, Radoslaw; Gorski, Krzysztof M.

1994-01-01

We obtain predictions for cosmic microwave background anisotropies at angular scales near 1 deg in the context of cold dark matter models with a nonzero cosmological constant, normalized to the Cosmic Background Explorer (COBE) Differential Microwave Radiometer (DMR) detection. The results are compared to those computed in the matter-dominated models. We show that the coherence length of the Cosmic Microwave Background (CMB) anisotropy is almost insensitive to cosmological parameters, and the rms amplitude of the anisotropy increases moderately with decreasing total matter density, while being most sensitive to the baryon abundance. We apply these results in the statistical analysis of the published data from the UCSB South Pole (SP) experiment (Gaier et al. 1992; Schuster et al. 1993). We reject most of the Cold Dark Matter (CDM)-Lambda models at the 95% confidence level when both SP scans are simulated together (although the combined data set renders less stringent limits than the Gaier et al. data alone). However, the Schuster et al. data considered alone as well as the results of some other recent experiments (MAX, MSAM, Saskatoon), suggest that typical temperature fluctuations on degree scales may be larger than is indicated by the Gaier et al. scan. If so, CDM-Lambda models may indeed provide, from a point of view of CMB anisotropies, an acceptable alternative to flat CDM models.
Doubling The Intensity Of An ERL Based Light Source

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

Andrew Hutton

2005-05-01

A light source based on an Energy Recovered Linac (ERL) [1] consists of a superconducting linac and a transfer line that includes wigglers and undulators to produce the synchrotron light. The transfer line brings the electron bunches back to the beginning of the linac so that their energy can be recovered when they traverse the linac a second time, {lambda}/2 out of RF phase. There is another interesting condition when the length of the transfer line is (n {+-} 1/4) {lambda}. In this case, the electrons drift through on the zero RF crossing, and make a further pass around themore » transfer line, effectively doubling the circulating current in the wigglers and undulators. On the third pass through the linac, they will be decelerated and their energy recovered. The longitudinal focusing at the zero crossing is a problem, but it can be canceled if the drifting beam sees a positive energy gradient for the first half of the linac and a negative gradient for the second half (or vice versa). This paper presents a proposal to use a double chicane at the center of the linac to provide this focusing inversion for the drifting beam while leaving the accelerating and decelerating beams on crest. [1] G. R. Neil, et al, Phys. Rev. Let. 84, 662 2000« less
Lau phase interferometer for the measurement of the temperature and temperature profile of a gaseous flame

NASA Astrophysics Data System (ADS)

Shakher, Chandra; Thakur, Madhuri

2001-05-01

In this paper we have investigated the utility of Lau phase interferometer with white light source and circular gratings to measure temperature and temperature profile of an axisymmetric flame. In Lau phase interferometer the two gratings are separated by infinite distance. The third grating is placed at a distance Z equals n.p2(lambda) , (where n is an integer, d is the pitch of the grating and (lambda) is the wavelength of the white light source). The sensitivity of the system is determined by the pitch 'p' of the grating and the distance Z between the gratings. If the distance Z between the two gratings is increased to enhance the sensitivity, the accuracy of measurement is reduced because of the reduction in the fringe contrast. In white light Lau phase interferometer the fringe contrast can be improved by optimizing the self-image plane and the pitch of the grating. From the recorded interferogram the angle of deflection ((phi) ) is measured and temperature at a different point of the flame is calculated. The temperature measured using Lau phase interferometer is in good agreement with the temperature measured by thermocouple and dataloger. Details of the theoretical analysis and experimental results are presented.
Measurements of J/{psi} and {psi}(2S) decays into {lambda}{lambda}{pi}{sup 0} and {lambda}{lambda}{eta}

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

Ablikim, M.; Bai, J. Z.; Cai, X.

2007-11-01

Using 58x10{sup 6} J/{psi} and 14x10{sup 6} {psi}(2S) events collected by the BESII detector at the BEPC, branching fractions or upper limits for the decays J/{psi} and {psi}(2S){yields}{lambda}{lambda}{pi}{sup 0} and {lambda}{lambda}{eta} are measured. For the isospin violating decays, the upper limits are determined to be B(J/{psi}{yields}{lambda}{lambda}{pi}{sup 0})<6.4x10{sup -5} and B[{psi}(2S){yields}{lambda}{lambda}{pi}{sup 0}]<4.9x10{sup -5} at the 90% confidence level. The isospin conserving process J/{psi}{yields}{lambda}{lambda}{eta} is observed for the first time, and its branching fraction is measured to be B(J/{psi}{yields}{lambda}{lambda}{eta})=(2.62{+-}0.60{+-}0.44)x10{sup -4}, where the first error is statistical and the second one is systematic. No {lambda}{lambda}{eta} signal is observed in {psi}(2S) decays, and B[{psi}(2S){yields}{lambda}{lambda}{eta}]<1.2x10{supmore » -4} is set at the 90% confidence level. Branching fractions of J/{psi} decays into {sigma}{sup +}{pi}{sup -}{lambda} and {sigma}{sup -}{pi}{sup +}{lambda} are also reported, and the sum of these branching fractions is determined to be B(J/{psi}{yields}{sigma}{sup +}{pi}{sup -}{lambda}+c.c.)=(1.52{+-}0.08{+-}0.16)x10{sup -3}.« less
Measurement of the branching fraction $${\\mathcal{B}}(\\Lambda^0_b\\rightarrow \\Lambda^+_c\\pi^-\\pi^+\\pi^-)$$ at CDF

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

Aaltonen, T.; /Helsinki Inst. of Phys.; Alvarez Gonzalez, B.

We report an analysis of the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} decay in a data sample collected by the CDF II detector at the Fermilab Tevatron corresponding to 2.4 fb{sup -1} of integrated luminosity. We reconstruct the currently largest samples of the decay modes {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2595){sup +}{pi}{sup -} (with {Lambda}{sub c}(2595){sup +} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}), {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2625){sup +}{pi}{sup -} (with {Lambda}{sub c}(2625){sup +} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}), {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup ++}{pi}{sup -}{pi}{sup -} (with {Sigma}{sub c}(2455){sup ++} {yields} {Lambda}{submore » c}{sup +}{pi}{sup +}), and {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455)0{pi}{sup +}{pi}{sup -} (with {Sigma}{sub c}(2455)0 {yields} {Lambda}{sub c}{sup +}{pi}{sup -}) and measure the branching fractions relative to the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -} branching fraction. We measure the ratio {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})/ {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -})=3.04 {+-} 0.33(stat){sub -0.55}{sup +0.70}(syst) which is used to derive {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})=(26.8{sub -11.2}{sup +11.9}) x 10{sup -3}.« less
Study of B{yields}{lambda}{sub c}{lambda}{sub c} and B{yields}{lambda}{sub c}{lambda}{sub c}K

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

Cheng, H.-Y.; Hsiao, Y.-K.; Chua, C.-K.

2009-06-01

We study the doubly charmful two-body and three-body baryonic B decays B{yields}{lambda}{sub c}{sup +}{lambda}{sub c}{sup -} and B{yields}{lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K. As pointed out before, a naive estimate of the branching ratio O(10{sup -8}) for the latter decay is too small by 3 to 4 orders of magnitude compared to experiment. Previously, it has been shown that a large enhancement for the {lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K production can occur due to a charmoniumlike resonance (e.g. X(4630) discovered by Belle) with a mass near the {lambda}{sub c}{lambda}{sub c} threshold. Motivated by the BABAR's observation of a resonance in themore » {lambda}{sub c}K system with a mass of order 2930 MeV, we study in this work the contribution to B{yields}{lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K from the intermediate state {xi}{sub c}(2980) which is postulated to be a first positive-parity excited D-wave charmed baryon state. Assuming that a soft qq quark pair is produced through the {sigma} and {pi} meson exchanges in the configuration for B{yields}{xi}{sub c}(2980){lambda}{sub c} and {lambda}{sub c}{lambda}{sub c}, it is found that branching ratios of B{yields}{lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K and B{yields}{lambda}{sub c}{sup +}{lambda}{sub c}{sup -} are of order 3.5x10{sup -4} and 5x10{sup -5}, respectively, in agreement with experiment except that the prediction for the {lambda}{sub c}{lambda}{sub c}K{sup -} is slightly smaller. In conjunction with our previous analysis, we conclude that the enormously large rate of B{yields}{lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K arises from the resonances {xi}{sub c}(2980) and X(4630)« less
Identification of human antibody fragment clones specific for tetanus toxoid in a bacteriophage. lambda. immunoexpression library

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

Mullinax, R.L.; Gross, E.A.; Amberg, J.R.

1990-10-01

The authors have applied a molecular biology approach to the identification of human monoclonal antibodies. Human peripheral blood lymphocyte mRNA was converted to cDNA and a select subset was amplified by the polymerase chain reaction. These products, containing coding sequences for numerous immunoglobulin heavy- and {kappa} light-chain variable and constant region domains, were inserted into modified bacteriophase {lambda} expression vectors and introduced into Escherichia coli by infection to yield a combinatorial immunoexpression library. Clones with binding activity to tetanus toxoid were identified by filter hybridization with radiolabeled antigen and appeared at a frequency of 0.2{percent} in the library. These humanmore » antigen binding fragments, consisting of a heavy-chain fragment covalently linked to a light chain, displayed high affinity of binding to tetanus toxoid with equilibrium constants in the nanomolar range but did not cross-react with other proteins tested. They estimate that this human immunoexpression library contains 20,000 clones with high affinity and specificity to our chosen antigen.« less
Identification of secreted and membrane-bound bat immunoglobulin using a Microchiropteran-specific mouse monoclonal antibody.

PubMed

Lee, William T; Jones, Derek D; Yates, Jennifer L; Winslow, Gary M; Davis, April D; Rudd, Robert J; Barron, Christopher T; Cowan, Cailyn

2016-12-01

Bat immunity has received increasing attention because some bat species are being decimated by the fungal disease, White Nose Syndrome, while other species are potential reservoirs of zoonotic viruses. Identifying specific immune processes requires new specific tools and reagents. In this study, we describe a new mouse monoclonal antibody (mAb) reactive with Eptesicus fuscus immunoglobulins. The epitope recognized by mAb BT1-4F10 was localized to immunoglobulin light (lambda) chains; hence, the mAb recognized serum immunoglobulins and B lymphocytes. The BT1-4F10 epitope appeared to be restricted to Microchiropteran immunoglobulins and absent from Megachiropteran immunoglobulins. Analyses of sera and other E. fuscus fluids showed that most, if not all, secreted immunoglobulins utilized lambda light chains. Finally, mAb BT1-4F10 permitted the identification of B cell follicles in splenic white pulp. This Microchiropteran-specific mAb has potential utility in seroassays; hence, this reagent may have both basic and practical applications for studying immune process. Copyright © 2016 Elsevier Ltd. All rights reserved.
The effect of line damping, magneto-optics and parasitic light on the derivation of sunspot vector magnetic fields

NASA Technical Reports Server (NTRS)

Skumanich, A.; Lites, B. W.

1985-01-01

The least square fitting of Stokes observations of sunspots using a Milne-Eddington-Unno model appears to lead, in many circumstances, to various inconsistencies such as anomalously large doppler widths and, hence, small magnetic fields which are significantly below those inferred solely from the Zeeman splitting in the intensity profile. It is found that the introduction of additional physics into the model such as the inclusion of damping wings and magneto-optic birefrigence significantly improves the fit to Stokes parameters. Model fits excluding the intensity profile, i.e., of both magnitude as well as spectral shape of the polarization parameters alone, suggest that parasitic light in the intensity profile may also be a source of inconsistencies. The consequences of the physical changes on the vector properties of the field derived from the Fe I lambda 6173 line for the 17 November 1975 spot as well as on the thermodynamic state are discussed. A Doppler width delta lambda (D) - 25mA is bound to be consistent with a low spot temperature and microturbulence, and a damping constant of a = 0.2.
Active optics null test system based on a liquid crystal programmable spatial light modulator

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

Ares, Miguel; Royo, Santiago; Sergievskaya, Irina

2010-11-10

We present an active null test system adapted to test lenses and wavefronts with complex shapes and strong local deformations. This system provides greater flexibility than conventional static null tests that match only a precisely positioned, individual wavefront. The system is based on a cylindrical Shack-Hartmann wavefront sensor, a commercial liquid crystal programmable phase modulator (PPM), which acts as the active null corrector, enabling the compensation of large strokes with high fidelity in a single iteration, and a spatial filter to remove unmodulated light when steep phase changes are compensated. We have evaluated the PPM's phase response at 635 nmmore » and checked its performance by measuring its capability to generate different amounts of defocus aberration, finding root mean squared errors below {lambda}/18 for spherical wavefronts with peak-to-valley heights of up to 78.7{lambda}, which stands as the limit from which diffractive artifacts created by the PPM have been found to be critical under no spatial filtering. Results of a null test for a complex lens (an ophthalmic customized progressive addition lens) are presented and discussed.« less
Measurement of the $$\\Lambda_b$$ cross section and the $$_{\\bar{\\Lambda}_b}$$ to $$\\Lambda_b$$ ratio with $$J/\\Psi \\Lambda$$ decays in $pp$ collisions at $$\\sqrt{s}=7$$ TeV

DOE PAGES

Chatrchyan, Serguei; et al.

2013-07-16

The Lambda(b) differential production cross section and the cross section ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Lambda(b) decays reconstructed in the exclusive final state J/Psi Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and Lambda to proton pion, using a data sample corresponding to an integrated luminosity of 1.9 inverse femtobarns. The product of the cross section times the branching ratio for Lambda(b) to J/Psi Lambda versusmore » pt(Lambda(b)) falls faster than that of b mesons. The measured value of the cross section times the branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06 +/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are statistical and systematic, respectively.« less
Exposure assessment of aluminum arc welding radiation.

PubMed

Peng, Chiung-yu; Lan, Cheng-hang; Juang, Yow-jer; Tsao, Ta-ho; Dai, Yu-tung; Liu, Hung-hsin; Chen, Chiou-jong

2007-10-01

The purpose of this study is to evaluate the non-ionizing radiation (NIR) exposure, especially optical radiation levels, and potential health hazard from aluminum arc welding processes based on the American Conference of Governmental Industrial Hygienists (ACGIH) method. The irradiance from the optical radiation emissions can be calculated with various biological effective parameters [i.e., S(lambda), B(lambda), R(lambda)] for NIR hazard assessments. The aluminum arc welding processing scatters bright light with NIR emission including ultraviolet radiation (UVR), visible, and infrared spectra. The UVR effective irradiance (Eeff) has a mean value of 1,100 microW cm at 100 cm distance from the arc spot. The maximum allowance time (tmax) is 2.79 s according to the ACGIH guideline. Blue-light hazard effective irradiance (EBlue) has a mean value of 1840 microW cm (300-700 nm) at 100 cm with a tmax of 5.45 s exposure allowance. Retinal thermal hazard effective calculation shows mean values of 320 mW cm(-2) sr(-1) and 25.4 mW (cm-2) (380-875 nm) for LRetina (spectral radiance) and ERetina (spectral irradiance), respectively. From this study, the NIR measurement from welding optical radiation emissions has been established to evaluate separate types of hazards to the eye and skin simultaneously. The NIR exposure assessment can be applied to other optical emissions from industrial sources. The data from welding assessment strongly suggest employees involved in aluminum welding processing must be fitted with appropriate personal protection devices such as masks and gloves to prevent serious injuries of the skin and eyes upon intense optical exposure.
The Effect of Habitual Smoking on VO2max

NASA Technical Reports Server (NTRS)

Wier, Larry T.; Suminski, Richard R.; Poston, Walker S.; Randles, Anthony M.; Arenare, Brian; Jackson, Andrew S.

2008-01-01

VO2max is associated with many factors, including age, gender, physical activity, and body composition. It is popularly believed that habitual smoking lowers aerobic fitness. PURPOSE: to determine the effect of habitual smoking on VO2max after controlling for age, gender, activity and BMI. METHODS: 2374 men and 375 women employed at the NASA/Johnson Space Center were measured for VO2max by indirect calorimetry (RER>=1.1), activity by the 11 point (0-10) NASA Physical Activity Status Scale (PASS), BMI and smoking pack-yrs (packs day*y of smoking). Age was recorded in years and gender was coded as M=1, W=0. Pack.y was made a categorical variable consisting of four levels as follows: Never Smoked (0), Light (1-10), Regular (11-20), Heavy (>20). Group differences were verified by ANOVA. A General Linear Models (GLM) was used to develop two models to examine the relationship of smoking behavior on VO2max. GLM #1(without smoking) determined the combined effects of age, gender, PASS and BMI on VO2max. GLM #2 (with smoking) determined the added effects of smoking (pack.y groupings) on VO2max after controlling for age, gender, PASS and BMI. Constant errors (CE) were calculated to compare the accuracy of the two models for estimating the VO2max of the smoking subgroups. RESULTS: ANOVA affirmed the mean VO2max of each pack.y grouping decreased significantly (p<0.01) as the level of smoking exposure increased. GLM #1 showed that age, gender, PASS and BMI were independently related with VO2max (R2 = 0.642, SEE = 4.90, p<0.001). The added pack.y variables in GLM #2 were statistically significant (R2 change = 0.7%, p<0.01). Post hoc analysis showed that compared to Never Smoked, the effects on VO2max from Light and Regular smoking habits were -0.83 and -0.85 ml.kg- 1.min-1 respectively (p<0.05). The effect of Heavy smoking on VO2max was -2.56 ml.kg- 1.min-1 (p<0.001). The CE s of each smoking group in GLM #2 was smaller than the CE s of the smoking group counterparts in GLM #1. CONCLUSIONS: After accounting for the effects of gender, age, PASS and BMI the effect of habitual smoking on reducing VO2max is minimal, about 0.85 ml/kg/min, until the habit exceeds 20 pack.y at which point an additional decrease of 1.71 ml/kg/min is noted. Adding pack.y data improves the accuracy of predicting the VO2max of smokers.
Serum Free Light Chain Assay and κ/λ Ratio: Performance in Patients With Monoclonal Gammopathy-High False Negative Rate for κ/λ Ratio

PubMed Central

Singh, Gurmukh

2017-01-01

Background Serum free light chain assay (SFLCA) and κ/λ ratio, and protein electrophoretic methods are used in the diagnosis and monitoring of monoclonal gammopathies. Methods Results for serum free light chains, serum and urine protein electrophoreses and immunofixation electrophoreses in 468 patients with a diagnosis of monoclonal gammopathy were compared. The results of the two methods were graded as concordant, non-concordant or discordant with the established diagnoses to assess the relative performance of the methods. Results of κ/λ ratio in samples with monoclonal protein detectable by electrophoretic methods were also analyzed. Results Protein electrophoreses results were concordant with the established diagnoses significantly more often than κ/λ ratio. The false negative rate for κ/λ ratio was higher than that for electrophoretic methods. κ/λ ratio was falsely negative in about 27% of the 1,860 samples with detectable monoclonal immunoglobulin. The false negative rate was higher in lesions with lambda chains (32%) than those with kappa chains (24%). The false negative rate for κ/λ ratio was over 55% in samples with monoclonal gammopathy of undetermined significance. Even at first encounter, the false negative rates for κ/λ ratios for monoclonal gammopathy of undetermined significance, smoldering myeloma and multiple myeloma were 66.98%, 23.08%, and 30.15%, respectively, with false negative rate for lambda chain lesions being higher. Conclusions Electrophoretic studies of serum and urine are superior to SFLCA and κ/λ ratio. Abnormal κ/λ ratio, per se, is not diagnostic of monoclonal gammopathy. A normal κ/λ ratio does not exclude monoclonal gammopathy. False negative rates for lesions with lambda chain are higher than those for lesions with kappa chains. Electrophoretic studies of urine are underutilized. Clinical usefulness and medical necessity of SFLCA and κ/λ ratio is of questionable value in routine clinical testing. PMID:27924175
Serum Free Light Chain Assay and κ/λ Ratio: Performance in Patients With Monoclonal Gammopathy-High False Negative Rate for κ/λ Ratio.

PubMed

Singh, Gurmukh

2017-01-01

Serum free light chain assay (SFLCA) and κ/λ ratio, and protein electrophoretic methods are used in the diagnosis and monitoring of monoclonal gammopathies. Results for serum free light chains, serum and urine protein electrophoreses and immunofixation electrophoreses in 468 patients with a diagnosis of monoclonal gammopathy were compared. The results of the two methods were graded as concordant, non-concordant or discordant with the established diagnoses to assess the relative performance of the methods. Results of κ/λ ratio in samples with monoclonal protein detectable by electrophoretic methods were also analyzed. Protein electrophoreses results were concordant with the established diagnoses significantly more often than κ/λ ratio. The false negative rate for κ/λ ratio was higher than that for electrophoretic methods. κ/λ ratio was falsely negative in about 27% of the 1,860 samples with detectable monoclonal immunoglobulin. The false negative rate was higher in lesions with lambda chains (32%) than those with kappa chains (24%). The false negative rate for κ/λ ratio was over 55% in samples with monoclonal gammopathy of undetermined significance. Even at first encounter, the false negative rates for κ/λ ratios for monoclonal gammopathy of undetermined significance, smoldering myeloma and multiple myeloma were 66.98%, 23.08%, and 30.15%, respectively, with false negative rate for lambda chain lesions being higher. Electrophoretic studies of serum and urine are superior to SFLCA and κ/λ ratio. Abnormal κ/λ ratio, per se , is not diagnostic of monoclonal gammopathy. A normal κ/λ ratio does not exclude monoclonal gammopathy. False negative rates for lesions with lambda chain are higher than those for lesions with kappa chains. Electrophoretic studies of urine are underutilized. Clinical usefulness and medical necessity of SFLCA and κ/λ ratio is of questionable value in routine clinical testing.
Circulating monoclonal immunoglobulins in Sjögren syndrome: prevalence and clinical significance in 237 patients.

PubMed

Brito-Zerón, Pilar; Ramos-Casals, Manuel; Nardi, Norma; Cervera, Ricard; Yagüe, Jordi; Ingelmo, Miguel; Font, Josep

2005-03-01

We conducted the current study to analyze the prevalence and clinical significance of circulating monoclonal immunoglobulins in patients with Sjögren syndrome (SS), focusing on the association with extraglandular features, immunologic markers, hematologic neoplasia, and hepatitis C virus (HCV) infection. We performed serum immunoelectrophoresis in 200 patients with primary SS and 37 patients with HCV-related SS. All patients fulfilled 4 or more of the 1993 European classification criteria for SS.Of the 200 patients with primary SS, 35 (18%) presented circulating monoclonal immunoglobulins. The monoclonal bands identified were 20 IgG (13 kappa, 7 lambda), 10 IgM (5 kappa, 5 lambda), 2 IgAkappa, and 3 free circulating light chains. Of the 37 SS-HCV patients, 16 (43%) had circulating monoclonal immunoglobulins. The monoclonal bands identified were 10 IgMkappa, 5 IgGlambda, and 1 free light lambda chain. Compared with primary SS patients, SS-HCV patients presented a higher frequency of monoclonal immunoglobulins (43% vs 18%, p = 0.001), with monoclonal IgMkappa being the most frequent monoclonal band. Six (12%) of the 51 SS patients with circulating monoclonal immunoglobulins presented hematologic neoplasia, compared with 3 (1.6%) of those without monoclonal immunoglobulins (p = 0.004; odds ratio = 8.13; 95% confidence intervals, 1.64-51.54). In 2 of the 6 patients with monoclonal immunoglobulins and lymphoproliferative disorders, a change of the monoclonal component was detected in previous immunoelectrophoresis determinations before the development of hematologic neoplasia. Circulating monoclonal immunoglobulins were detected in nearly 20% of patients with primary SS, with monoclonal IgG being the most frequent type of immunoglobulin detected. In SS-HCV patients, the prevalence of monoclonal immunoglobulins was higher (43%), with monoclonal IgM being the most frequent type found. SS-HCV patients presented a more restrictive monoclonal expression (limited to either monoclonal IgMkappa or monoclonal IgGlambda) than primary SS patients, who showed all types of heavy and light chains.
[The expression of interferon-lambda1 in CHO cell].

PubMed

Yuan, Wu-Mei; Ma, Fen-Lian; Zhang, Qian; Zheng, Wen-Zhi; Zheng, Li-Shu

2013-06-01

To construct the eukaryotic expression vector PCI-dhfr-lambda1 and PCI-dhfr-SP163-lambda1 which linked the enhancer SP163 with interferon lambda1. Then express the interferon lambda1 in CHO (dhfr-) cells. Using PCR method to introduce the restriction enzyme sites and through the fusion PCR binding the enhancer with the interferon Lambda1. After sequenced, lambda1 and SP163-lambda1 was inserted into PCI-dhfr forming the expression vector PCI-dhfr-lambda1 and PCI-dhfr-SP163-lambda1 which was constructed successfully confirming by sequencing. Then the expressing vectors were transfected into CHO (dhfr-) cells using liposome transfection method and interferon lambda1 protein was assayed with indirect immunofluorescence and Western Blot. Using cytopathic effect inhibition evaluated the antiviral activity of interferon lambda1. Successfully constructing the eukaryotic expression vectors of interferon lambda and the vectors could express interferon lambda1. The result of immunofluorescence showed the enhancer developed the expression of interferon lambda1. Detecting the interferon lambda1 in CHO (dhfr-) cells after transfecting 48 hour using Western Blot. The cytopathic effect inhibition showed the expressed interferon lambda1 has the antiviral activity. Successfully expressed the interferon lambda1 in CHO (dhfr-) cells and the protein possesses antiviral activity, which may supply a valuable basis for building the stable cell line of interferon lambda1.

Energy of the ground and 2{sup +} excited states of {sub {lambda}}{sub {lambda}}{sup 10}Be: A partial ten-body model

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

Shoeb, Mohammad; Sonika

2009-08-15

The energies of the ground and excited 2{sup +} states of {sub {lambda}}{sub {lambda}}{sup 10}Be have been calculated variationally in the Monte Carlo framework. The hypernucleus is treated as a partial ten-body problem in the {lambda}{lambda}+{alpha}{alpha} model where nucleonic degrees of freedom of {alpha}'s are taken into consideration ignoring the antisymmetrization between two {alpha}'s. The central two-body {lambda}N and {lambda}{lambda} and the three-body dispersive and two-pion exchange {lambda}NN forces, constrained by the {lambda}p scattering data and the observed ground state energies of {sub {lambda}}{sup 5}He and {sub {lambda}}{sub {lambda}}{sup 6}He, are employed. The product-type trial wave function predicts binding energymore » for the ground state considerably less than for the event reported by Danysz et al.; however, it is consistent with the value deduced assuming a {gamma} ray of 3.04 MeV must have escaped undetected in the decay of the product {sub {lambda}}{sup 9}Be* {yields} {sub {lambda}}{sup 9}Be+{gamma} of the emulsion event {sub {lambda}}{sub {lambda}}{sup 10}Be{yields} {pi}{sup -}+p+{sub {lambda}}{sup 9}Be* and for the excited 2{sup +} state closer to the value measured in the Demachi-Yanagi event. The hypernucleus {sub {lambda}}{sub {lambda}}{sup 10}Be has an oblate shape in the excited state. These results are consistent with the earlier four-body {alpha} cluster model approach where {alpha}'s are assumed to be structureless entities.« less
Effectiveness of Haemodiafiltration with Heat Sterilized High-Flux Polyphenylene HF Dialyzer in Reducing Free Light Chains in Patients with Myeloma Cast Nephropathy

PubMed Central

2015-01-01

Introduction In cases of myeloma cast nephropathy in need of haemodialysis (HD), reduction of free light chains using HD with High-Cut-Off filters (HCO-HD), in combination with chemotherapy, may be associated with better renal recovery. The aim of the present study is to evaluate the effectiveness of haemodiafiltration (HDF) in reducing free light chain levels using a less expensive heat sterilized high-flux polyphenylene HF dialyzer (HF-HDF). Methods In a single-centre prospective cohort study, 327 dialysis sessions were performed using a 2.2 m2 heat sterilized high-flux polyphenylene HF dialyzer (Phylther HF22SD), a small (1.1m2) or large (2.1 m2) high-cut-off (HCO) dialyzer (HCOS and HCOL) in a cohort of 16 patients presenting with dialysis-dependent acute cast nephropathy and elevated free light chains (10 kappa, 6 lambda). The outcomes of the study were the mean reduction ratio (RR) of kappa and lambda, the proportion of treatments with an RR of at least 0.65, albumin loss and the description of patient outcomes. Statistical analysis was performed using linear and logistic regression through generalized estimating equation analysis so as to take into account repeated observation within subjects and adjust for session duration. Results There were no significant differences in the estimated marginal mean of kappa RR, which were respectively 0.67, 0.69 and 0.70 with HCOL-HD, HCOS-HDF and HF-HDF (P = 0.950). The estimated marginal mean of the proportions of treatments with a kappa RR ≥0.65 were 68%, 63% and 71% with HCOL-HD, HCOS-HDF and HF-HDF, respectively (P = 0.913). The estimated marginal mean of lambda RR were higher with HCOL-HDF (0.78), compared to HCOL-HD and HF-HDF (0.62, and 0.61 respectively). The estimated marginal mean proportion of treatments with a lambda RR ≥0.65 were higher with HCOL-HDF (81%), compared to 57% in HF-HDF (P = 0.042). The median albumin loss were 7, 21 and 63 g/session with HF-HDF, HCOL-HD and HCOL-HDF respectively (P = 0.044). Among survivors, 9 out of 10 episodes of acute kidney injuries became dialysis-independent following a median time of renal replacement therapy of 40 days (range 7–181). Conclusion Therefore, in patients with acute dialysis-dependent myeloma cast nephropathy, in addition to chemotherapy, HDF with a heat sterilized high-flux polyphenylene HF dialyzer could offer an alternative to HCO dialysis for extracorporeal kappa reduction with lower albumin loss. PMID:26466100
Max-AUC Feature Selection in Computer-Aided Detection of Polyps in CT Colonography

PubMed Central

Xu, Jian-Wu; Suzuki, Kenji

2014-01-01

We propose a feature selection method based on a sequential forward floating selection (SFFS) procedure to improve the performance of a classifier in computerized detection of polyps in CT colonography (CTC). The feature selection method is coupled with a nonlinear support vector machine (SVM) classifier. Unlike the conventional linear method based on Wilks' lambda, the proposed method selected the most relevant features that would maximize the area under the receiver operating characteristic curve (AUC), which directly maximizes classification performance, evaluated based on AUC value, in the computer-aided detection (CADe) scheme. We presented two variants of the proposed method with different stopping criteria used in the SFFS procedure. The first variant searched all feature combinations allowed in the SFFS procedure and selected the subsets that maximize the AUC values. The second variant performed a statistical test at each step during the SFFS procedure, and it was terminated if the increase in the AUC value was not statistically significant. The advantage of the second variant is its lower computational cost. To test the performance of the proposed method, we compared it against the popular stepwise feature selection method based on Wilks' lambda for a colonic-polyp database (25 polyps and 2624 nonpolyps). We extracted 75 morphologic, gray-level-based, and texture features from the segmented lesion candidate regions. The two variants of the proposed feature selection method chose 29 and 7 features, respectively. Two SVM classifiers trained with these selected features yielded a 96% by-polyp sensitivity at false-positive (FP) rates of 4.1 and 6.5 per patient, respectively. Experiments showed a significant improvement in the performance of the classifier with the proposed feature selection method over that with the popular stepwise feature selection based on Wilks' lambda that yielded 18.0 FPs per patient at the same sensitivity level. PMID:24608058
Max-AUC feature selection in computer-aided detection of polyps in CT colonography.

PubMed

Xu, Jian-Wu; Suzuki, Kenji

2014-03-01

We propose a feature selection method based on a sequential forward floating selection (SFFS) procedure to improve the performance of a classifier in computerized detection of polyps in CT colonography (CTC). The feature selection method is coupled with a nonlinear support vector machine (SVM) classifier. Unlike the conventional linear method based on Wilks' lambda, the proposed method selected the most relevant features that would maximize the area under the receiver operating characteristic curve (AUC), which directly maximizes classification performance, evaluated based on AUC value, in the computer-aided detection (CADe) scheme. We presented two variants of the proposed method with different stopping criteria used in the SFFS procedure. The first variant searched all feature combinations allowed in the SFFS procedure and selected the subsets that maximize the AUC values. The second variant performed a statistical test at each step during the SFFS procedure, and it was terminated if the increase in the AUC value was not statistically significant. The advantage of the second variant is its lower computational cost. To test the performance of the proposed method, we compared it against the popular stepwise feature selection method based on Wilks' lambda for a colonic-polyp database (25 polyps and 2624 nonpolyps). We extracted 75 morphologic, gray-level-based, and texture features from the segmented lesion candidate regions. The two variants of the proposed feature selection method chose 29 and 7 features, respectively. Two SVM classifiers trained with these selected features yielded a 96% by-polyp sensitivity at false-positive (FP) rates of 4.1 and 6.5 per patient, respectively. Experiments showed a significant improvement in the performance of the classifier with the proposed feature selection method over that with the popular stepwise feature selection based on Wilks' lambda that yielded 18.0 FPs per patient at the same sensitivity level.
Beauty Baryons at CDF and DO

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

Kryemadhi, Abaz

The results from Tevatron in the baryonic sector are presented. The lifetime of {lambda}b {yields} J/{psi}{lambda}, the observation of hadronic decay of {lambda}b {yields} {lambda}c{pi}, the semileptonic decays of {lambda}b {yields} {lambda}c{mu}{nu}, the hadronization of the b-baryons, and the {lambda}b decays to {lambda}b {yields} p{pi} and {lambda}b {yields} pK are discussed. These measurements paint a nice picture of our understanding of the beauty baryons.
Improved measurement of the form factors in the decay lambda+c-->lambda + nue.

PubMed

Hinson, J W; Huang, G S; Lee, J; Miller, D H; Pavlunin, V; Rangarajan, R; Sanghi, B; Shibata, E I; Shipsey, I P J; Cronin-Hennessy, D; Park, C S; Park, W; Thayer, J B; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Stroynowski, R; Artuso, M; Boulahouache, C; Blusk, S; Dambasuren, E; Dorjkhaidav, O; Mountain, R; Muramatsu, H; Nandakumar, R; Skwarnicki, T; Stone, S; Wang, J C; Csorna, S E; Danko, I; Bonvicini, G; Cinabro, D; Dubrovin, M; McGee, S; Bornheim, A; Lipeles, E; Pappas, S P; Shapiro, A; Sun, W M; Weinstein, A J; Briere, R A; Chen, G P; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Adam, N E; Alexander, J P; Berkelman, K; Boisvert, V; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Galik, R S; Gibbons, L; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Magerkurth, A; Mahlke-Krüger, H; Meyer, T O; Mistry, N B; Patterson, J R; Peterson, D; Pivarski, J; Richichi, S J; Riley, D; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Thayer, J G; Urner, D; Wilksen, T; Warburton, A; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Potlia, V; Stoeck, H; Yelton, J; Benslama, K; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Lowrey, N; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Besson, D; Anderson, S; Frolov, V V; Gong, D T; Kubota, Y; Li, S Z; Poling, R; Smith, A; Stepaniak, C J; Urheim, J; Metreveli, Z; Seth, K K; Tomaradze, A; Zweber, P; Ahmed, S; Alam, M S; Ernst, J; Jian, L; Saleem, M; Wappler, F; Arms, K; Eckhart, E; Gan, K K; Gwon, C; Honscheid, K; Kagan, H; Kass, R; Pedlar, T K; von Toerne, E; Severini, H; Skubic, P; Dytman, S A; Mueller, J A; Nam, S; Savinov, V

2005-05-20

Using the CLEO detector at the Cornell Electron Storage Ring, we have studied the distribution of kinematic variables in the decay lambda(+)(c)lambda--> e(+)nu(e). By performing a four-dimensional maximum likelihood fit, we determine the form factor ratio, R= f(2)/f(1) = -0.31 +/- 0.05(stat) +/- 0.04(syst), the pole mass, M(pole) = [2.21 +/- 0.08(stat) +/- 0.14(syst)] GeV/c(2), and the decay asymmetry parameter of the lambda(+)(c), alpha (lambda(c)) = -0.86 +/-0.03(stat) +/- 0.02(syst), for q(2) = 0.67 (GeV/c(2))(2). We compare the angular distributions of the lambda(+)(c) and lambda(-)(c) and find no evidence for CP violation: A(lambda(c)) = (alpha(lambda(c)) + alpha (lambda(c)))/(alpha(lambda(c))-alpha(lambda(c))) = 0.00 +/- 0.03(stat) +/- 0.01(syst) +/- 0.02, where the third error is from the uncertainty in the world average of the CP-violating parameter, A(lambda), for ppi(-).
MAX-DOAS measurements of aerosol, HCHO, and NO2 over Los Angeles from an elevated mountaintop site

NASA Astrophysics Data System (ADS)

Cheung, Ross

MAX-DOAS measurements of aerosol, HCHO, and NO2 over Los Angeles from an elevated mountaintop site. By. Ross Cheung. Doctor of Philosophy in Atmospheric and Oceanic Sciences. University of California, Los Angeles, 2016. Professor Jochen Stutz, Chair. Differential Optical Absorption Spectroscopy (DOAS) has become a popular technique for measuring atmospheric trace gases using UV/Vis narrow-band absorption features along a light path through the atmosphere. The UCLA Multi-Axis DOAS instrument (MAX-DOAS) is a ground-based spectrometer currently located at Mt. Wilson, California (1700 meters above sea level) that measures solar scattered light at various viewing elevation angles. Since May of 2010, it has been taking regular measurements of atmospheric pollutants in the boundary layer of the atmosphere in and above the Los Angeles Basin. This thesis presents the experimental setup and spectral retrievals, as well as results of our observations of measurements of NO2 and HCHO from Mt. Wilson. Radiative transfer modeling efforts of the deployment at Mt. Wilson will be presented, as well as our efforts to model and account for the effects of clouds and aerosols on MAX-DOAS measurements. Because of the unique challenges presented by aerosols in the ultraviolet and visible light region in a polluted urban boundary layer, new techniques were developed to account for and quantify these effects. Observations of path-integrated NO2 and HCHO, some of the primary precursors to ozone formation in the lower troposphere, as well as aerosol extinctions using the UCLA MAX-DOAS will be presented, and the advantages of a mountaintop measurement strategy will be discussed in light of the amount of vertical information that can be retrieved from this approach. The techniques developed to improve the optimal estimation of vertical aerosol extinction profiles and trace gas concentration profiles will be discussed. Finally, an application of these observations uses the ratio of HCHO/NO2 to study the dependency of ozone formation on nitrogen oxides and VOCs will be presented.
Complexation equilibria and spectrophotometric determination of iron(III) with 1-amino-4-hydroxyanthraquinone.

PubMed

Abu-Bakr, M S; Sedaira, H; Hashem, E Y

1994-10-01

The complex equilibria of iron(III) with 1-amino-4-hydroxyanthraquinone (AMHA) were studied spectrophotometrically in 40% (v/v) ethanol and an ionic strength of 0.1M (NaClO(4)). The complexation reactions were demonstrated and characterized using graphical logarithmic analysis of the absorbance-pH graphs. A simple, rapid, selective and sensitive method for the spectrophotometric determination of trace amounts of Fe(III) is developed based on the formation of Fe(AMHA) complex at pH 2.5 (lambda(max) = 640 nm, epsilon approximately = 2.1 x 10(4) L. mol(-1) . cm(-1)) in the presence of a large number of foreign ions. Interferences caused by palladium(II) was masked by the addition of cyanide ions. The method has been applied to the determination of iron in some synthetic samples and polymetallic iron ores.
Antibacterial colorants: characterization of prodiginines and their applications on textile materials.

PubMed

Alihosseini, Farzaneh; Ju, Kou-San; Lango, Jozsef; Hammock, Bruce D; Sun, Gang

2008-01-01

A strain of Vibrio sp. isolated from marine sediments produced large quantities of bright red pigments that could be used to dye many fibers including wool, nylon, acrylics, and silk. Characterization of the pigments by electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) revealed three prodiginine-like structures with nonpolar characteristics and low molecular mass. UV-visible spectra of the major constituent in methanol solution showed absorbance at lambda max 530 nm wavelength. The accurate mass result showed that the main isolated product has a molecular mass of m/z 323.1997. Further analysis using mass fragmentation (MS/MS), 1H NMR, COSY, HMQC NMR and DEPT confirmed the detailed structure of the pigment with an elementary composition of C20H25N3O. Fabrics dyed with the microbial prodiginines demonstrated antibacterial activity.
HST Spatially Resolved Spectra of the Accretion Disc and Gas Stream of the Nova-Like Variable UX Ursae Majoris

NASA Technical Reports Server (NTRS)

Baptista, Raymundo; Horne, Keith; Wade, Richard A.; Hubeny, Ivan; Long, Knox S.; Rutten, Rene G. M.

1998-01-01

Time-resolved eclipse spectroscopy of the nova-like variable UX UMa obtained with the Hubble Space Telescope/Faint Object Spectrograph (HST/FOS) on 1994 August and November is analysed with eclipse mapping techniques to produce spatially resolved spectra of its accretion disk and gas stream as a function of distance from the disk centre. The inner accretion disk is characterized by a blue continuum filled with absorption bands and lines, which cross over to emission with increasing disk radius, similar to that reported at optical wavelengths. The comparison of spatially resolved spectra at different azimuths reveals a significant asymmetry in the disk emission at ultraviolet (UV) wavelengths, with the disk side closest to the secondary star showing pronounced absorption by an 'iron curtain' and a Balmer jump in absorption. These results suggest the existence of an absorbing ring of cold gas whose density and/or vertical scale increase with disk radius. The spectrum of the infalling gas stream is noticeably different from the disc spectrum at the same radius suggesting that gas overflows through the impact point at the disk rim and continues along the stream trajectory, producing distinct emission down to 0.1 R(sub LI). The spectrum of the uneclipsed light shows prominent emission lines of Lyalpha, N v lambda1241, SiIV Lambda 1400, C IV Lambda 1550, HeII Lambda 1640, and MgII Lambda 2800, and a UV continuum rising towards longer wavelengths. The Balmer jump appears clearly in emission indicating that the uneclipsed light has an important contribution from optically thin gas. The lines and optically thin continuum emission are most probably emitted in a vertically extended disk chromosphere + wind. The radial temperature profiles of the continuum maps are well described by a steady-state disc model in the inner and intermediate disk regions (R greater than or equal to 0.3R(sub LI) ). There is evidence of an increase in the mass accretion rate from August to November (from V = 10 (exp -8.3 +/-0.1) to 10(exp -8.1 +/- 0.1 solar mass yr(exp -1)), in accordance with the observed increase in brightness. Since the UX UMA disc seems to be in a high mass accretion, high-viscosity regime in both epochs, this result suggests that the mass transfer rate of UX UMA varies substantially (approximately equal to 50 per cent) on time-scales of a few months. It is suggested that the reason for the discrepancies between the prediction of the standard disk model and observations is not an inadequate treatment of radiative transfer in the disc atmosphere, but rather the presence of addition important sources of light in the system besides the accretion disk (e.g., optically thin contiuum emission from the disk wind and possible absorption by circumstellar cool gas).
Light response characteristics of a morphologically diverse group of southern hemisphere conifers as measured by chlorophyll fluorescence.

PubMed

Brodribb, T; Hill, Robert S

1997-03-01

Unlike northern hemisphere conifer families, the southern family, Podocarpaceae, produces a great variety of foliage forms ranging from functionally broad-, to needle-leaved. The production of broad photosynthetic surfaces in podocarps has been linked qualitatively to low-light-environments, and we undertook to assess the validity of this assumption by measuring the light response of a morphologically diverse group of podocarps. The light response, as apparent photochemical electron transport rate (ETR), was measured by modulated fluorescence in ten species of this family and six associated species (including five Cupressaceae and one functionally needle-leaved angiosperm) all grown under identical glasshouse conditions. In all species, ETR was found to increase as light intensity increased, reaching a peak value (ETR max ) at saturating quantum flux (PPFD sat ), and decreasing thereafter. ETR max ranged from 217 μmol electrons · m -2 · s -1 at a PPFD sat of 1725 μmol photons · m -2 · s -1 in Actinostrobus acuminatus to an ETR of 60 μmol electrons · m -2 · s -1 at a PPFD sat of 745 μmol electrons · m -2 · s -1 in Podocarpus dispermis. Good correlations were observed between ETR max and both PPFD sat and maximum assimilation rate measured by gas-exchange analysis. The effective quantum yield at light saturation remained constant in all species with an average value of 0.278 ± 0.0035 determined for all 16 species. Differences in the shapes of light response curves were related to differences in the response of non-photochemical quenching (q n ), with q n saturating faster in species with low PPFD sat . Amongst the species of Podocarpaceae, the log of average shoot width was well correlated with PPFD sat , wider leaves saturating at lower light intensities. This suggests that broadly flattened shoots in the Podocarpaceae are an adaptation to low light intensity.
Observation of B{sup 0}{yields}{lambda}{lambda}K{sup 0} and B{sup 0}{yields}{lambda}{lambda}K*{sup 0} at Belle

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

Chang, Y.-W.; Wang, M.-Z.; Chao, Y.

2009-03-01

We study the charmless decays B{yields}{lambda}{lambda}h, where h stands for {pi}{sup +}, K{sup +}, K{sup 0},K*{sup +}, or K*{sup 0}, using a 605 fb{sup -1} data sample collected at the {upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric energy e{sup +}e{sup -} collider. We observe B{sup 0}{yields}{lambda}{lambda}K{sup 0} and B{sup 0}{yields}{lambda}{lambda}K*{sup 0} with branching fractions of (4.76{sub -0.68}{sup +0.84}(stat){+-}0.61(syst))x10{sup -6} and (2.46{sub -0.72}{sup +0.87}{+-}0.34)x10{sup -6}, respectively. The significances of these signals in the threshold-mass enhanced mass region, M{sub {lambda}}{sub {lambda}}<2.85 GeV/c{sup 2}, are 12.4{sigma} and 9.3{sigma}, respectively. We also update the branching fraction B(B{sup +}{yields}{lambda}{lambda}K{sup +})=(3.38{sub -0.36}{sup +0.41}{+-}0.41)x10{supmore » -6} with better accuracy, and report the following measurement or 90% confidence level upper limit in the threshold-mass-enhanced region: B(B{sup +}{yields}{lambda}{lambda}K*{sup +})=(2.19{sub -0.88}{sup +1.13}{+-}0.33)x10{sup -6} with 3.7{sigma} significance; B(B{sup +}{yields}{lambda}{lambda}{pi}{sup +})<0.94x10{sup -6}. A related search for B{sup 0}{yields}{lambda}{lambda}D{sup 0} yields a branching fraction B(B{sup 0}{yields}{lambda}{lambda}D{sup 0})=(1.05{sub -0.44}{sup +0.57}{+-}0.14)x10{sup -5}. This may be compared with the large, {approx}10{sup -4}, branching fraction observed for B{sup 0}{yields}ppD{sup 0}. The M{sub {lambda}}{sub {lambda}} enhancements near threshold and related angular distributions for the observed modes are also reported.« less
Preparation of new crosslinking agents and additives for use in polymer electrolyte membranes (PEMs) for fuel cell applications

NASA Astrophysics Data System (ADS)

Zhou, Yangliu

The most commonly used proton conductive membrane in polymer electrolyte membrane fuel cells (PEMFC) and direct methanol fuel cells (DMFC) studies to date is DuPont's NafionRTM, which is a perfluorinated copolymer of tetrafluoroethylene (TFE) and perfluorovinyl ether with a pendant sulfonic acid group. A focus of this work is to find ways to improve the performance of NafionRTM membranes. Crosslinking the TFE chains of fluorinated ionomeric copolymers to improve their thermal and mechanical stability is a proven route to this goal. A straightforward synthetic route to perfluorinated divinyl ethers of the formula CF2=CFO(CF 2)3[OCF(CF3)CF2]mOCF=CF 2 (m = 0-1) has been demonstrated. The compounds CF2=CFO(CF 2)3OCF=CF2 and CF2=CFO(CF2) 3OCF(CF3)CF2OCF=CF2 were prepared and characterized by GC-MS, 13C and 19F NMR, and gas-IR spectroscopy. Synthetic routes to fluorosulfato-tetrafluoropropionyl fluoride [FSO3CF2CF2C(O)F] and difluoromalonyl difluoride [F(O)CCF2C(O)F] with improved yields were found. The second focus of the dissertation was the development of fluorous triarylphosphines for use as new doping materials for the modification of NafionRTM membranes and for use as ligands in catalysts for biphasic catalysis. The synthesis and characterization of a series of new polyhexafluoropropylene oxide derivatives for preparation of fluorous triarylphosphines and phosphonium salts was studied, such as F[CF(CF3)CF2O] 4CF(CF3)CH2CH2I, F[CF(CF3)CF 2O]4CF(CF3)CH=CH2, F[CF(CF3)CF 2O]4CF(CF3) CH2CH2C6H5, and F[CF(CF 3)CF2O]4CF(CF3)CH2CH 2C6H4Br. In a separate study, the photochlorination of 2,2,3,3-tetrafluoro-1-propanol (HCF2CF2CH2OH) and 2,2,3,3-tetrafluoropropyl 2,2,3,3-tetrafluoropropionate [HCF2CF2C(O)OCH2 CF2CF2H] with super diazo blue light (lambda max = 420 nm) were investigated. The photochemical products are different from those obtained under mercury light (lambda = 253.7nm). A new compound ClCF2CF2C(O)OC(H)ClCF2CF2Cl was prepared and characterized by GC-MS, elemental analysis, 1H, 13C and 19F NMR, and gas-IR spectroscopy.
Experimental medium energy physics

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

Barnes, P.D.

1991-01-01

This report discusses the following topics: Search for the H Dibaryon at the AGS; Hypernuclear Weak Decay Studies at the AGS; Relativistic Proton-Nucleus and Heavy Ion-Nucleus Collisions at the SPS; Hyperon-Antihyperon Production studies at LEAR; Hyperon Photoproduction at CEBAF; Double Lambda Hypernuclei; Weak Decay of Light Hypernuclei; and {pi}{sup 0}/{gamma}Detection with the CMU Scintillator Arrays.
Initiation of lambda DNA replication. The Escherichia coli small heat shock proteins, DnaJ and GrpE, increase DnaK's affinity for the lambda P protein.

PubMed

Osipiuk, J; Georgopoulos, C; Zylicz, M

1993-03-05

It is known that the initiation of bacteriophage lambda replication requires the orderly assembly of the lambda O.lambda P.DnaB helicase protein preprimosomal complex at the ori lambda DNA site. The DnaK, DnaJ, and GrpE heat shock proteins act together to destabilize the lambda P.DnaB complex, thus freeing DnaB and allowing it to unwind lambda DNA near the ori lambda site. The first step of this disassembly reaction is the binding of DnaK to the lambda P protein. In this report, we examined the influence of the DnaJ and GrpE proteins on the stability of the lambda P.DnaK complex. We present evidence for the existence of the following protein-protein complexes: lambda P.DnaK, lambda P.DnaJ, DnaJ.DnaK, DnaK.GrpE, and lambda P.DnaK.GrpE. Our results suggest that the presence of GrpE alone destabilizes the lambda P.DnaK complex, whereas the presence of DnaJ alone stabilizes the lambda P.DnaK complex. Using immunoprecipitation, we show that in the presence of GrpE, DnaK exhibits a higher affinity for the lambda P.DnaJ complex than it does alone. Using cross-linking with glutaraldehyde, we show that oligomeric forms of DnaK exhibit a higher affinity for lambda P than monomeric DnaK. However, in the presence of GrpE, monomeric DnaK can efficiently bind lambda P protein. These findings help explain our previous results, namely that in the GrpE-dependent lambda DNA replication system, the DnaK protein requirement can be reduced up to 10-fold.
Physical interactions between bacteriophage and Escherichia coli proteins required for initiation of lambda DNA replication.

PubMed

Liberek, K; Osipiuk, J; Zylicz, M; Ang, D; Skorko, J; Georgopoulos, C

1990-02-25

The process of initiation of lambda DNA replication requires the assembly of the proper nucleoprotein complex at the origin of replication, ori lambda. The complex is composed of both phage and host-coded proteins. The lambda O initiator protein binds specifically to ori lambda. The lambda P initiator protein binds to both lambda O and the host-coded dnaB helicase, giving rise to an ori lambda DNA.lambda O.lambda P.dnaB structure. The dnaK and dnaJ heat shock proteins have been shown capable of dissociating this complex. The thus freed dnaB helicase unwinds the duplex DNA template at the replication fork. In this report, through cross-linking, size chromatography, and protein affinity chromatography, we document some of the protein-protein interactions occurring at ori lambda. Our results show that the dnaK protein specifically interacts with both lambda O and lambda P, and that the dnaJ protein specifically interacts with the dnaB helicase.
Difluorophosphoryl nitrene F2P(O)N: matrix isolation and unexpected rearrangement to F2PNO.

PubMed

Zeng, Xiaoqing; Beckers, Helmut; Willner, Helge; Neuhaus, Patrik; Grote, Dirk; Sander, Wolfram

2009-12-14

Triplet difluorophosphoryl nitrene F(2)P(O)N (X(3)A'') was generated on ArF excimer laser irradiation (lambda=193 nm) of F(2)P(O)N(3) in solid argon matrix at 16 K, and characterized by its matrix IR, UV/Vis, and EPR spectra, in combination with DFT and CBS-QB3 calculations. On visible light irradiation (lambda>420 nm) at 16 K F(2)P(O)N reacts with molecular nitrogen and some of the azide is regenerated. UV irradiation (lambda=255 nm) of F(2)P(O)N (X(3)A'') induced a Curtius-type rearrangement, but instead of a 1,3-fluorine shift, nitrogen migration to give F(2)PON is proposed to be the first step of the photoisomerization of F(2)P(O)N into F(2)PNO (difluoronitrosophosphine). Formation of novel F(2)PNO was confirmed with (15)N- and (18)O-enriched isotopomers by IR spectroscopy and DFT calculations. Theoretical calculations predict a rather long P-N bond of 1.922 A [B3LYP/6-311+G(3df)] and low bond-dissociation energy of 76.3 kJ mol(-1) (CBS-QB3) for F(2)PNO.
Retaining the equilibrium point hypothesis as an abstract description of the neuromuscular system.

PubMed

Tresilian, J R

1999-01-01

The lambda version of the equilibrium point (EP) hypothesis for motor control is examined in light of recent criticisms of its various instantiations. Four important assumptions that have formed the basis for recent criticism are analyzed: First, the assumption that intact muscles possess invariant force-length characteristics (ICs). Second, that these ICs are of the same form in agonist-antagonist pairs. Third, that muscle control is monoparametric and that the control parameter, lambda, can be given a neurophysiological interpretation. Fourth, that reflex loop time delays and the known, asymmetric, nonlinear mechanical properties of muscles can be ignored. Mechanical and neurophysiological investigations of the neuromuscular system suggests that none of these assumptions is likely to be correct. This has been taken to mean that the EP hypothesis is oversimplified and a new approach is needed. It is argued that such an approach can be provided without rejecting the EP hypothesis, rather to regard it as an input-output description of muscle and associated segmental circuits. The operation of the segmental circuitry can be interpreted as having the function, at least in part, of compensating for a variety of nonlinearities and asymmetries such that the overall system implements the lambda-EP model equations.
In vivo gene delivery and expression by bacteriophage lambda vectors.

PubMed

Lankes, H A; Zanghi, C N; Santos, K; Capella, C; Duke, C M P; Dewhurst, S

2007-05-01

Bacteriophage vectors have potential as gene transfer and vaccine delivery vectors because of their low cost, safety and physical stability. However, little is known concerning phage-mediated gene transfer in mammalian hosts. We therefore performed experiments to examine phage-mediated gene transfer in vivo. Mice were inoculated with recombinant lambda phage containing a mammalian expression cassette encoding firefly luciferase (luc). Efficient, dose-dependent in vivo luc expression was detected, which peaked within 24 h of delivery and declined to undetectable levels within a week. Display of an integrin-binding peptide increased cellular internalization of phage in vitro and enhanced phage-mediated gene transfer in vivo. Finally, in vivo depletion of phagocytic cells using clodronate liposomes had only a minor effect on the efficiency of phage-mediated gene transfer. Unmodified lambda phage particles are capable of transducing mammalian cells in vivo, and may be taken up -- at least in part -- by nonphagocytic mechanisms. Surface modifications that enhance phage uptake result in more efficient in vivo gene transfer. These experiments shed light on the mechanisms involved in phage-mediated gene transfer in vivo, and suggest new approaches that may enhance the efficiency of this process.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Y.; Sun, C.P.

We study the propagation of a probe light in an ensemble of {lambda}-type atoms, utilizing the dynamic symmetry as recently discovered when the atoms are coupled to a classical control field and a quantum probe field [Sun et al., Phys. Rev. Lett. 91, 147903 (2003)]. Under two-photon resonance, we calculate the group velocity of the probe light with collective atomic excitations. Our result gives the dependence of the group velocity on the common one-photon detuning, and can be compared with the recent experiment of E. E. Mikhailov, Y. V. Rostovtsev, and G. R. Welch, e-print quant-ph/0309173.

Amino terminal sequence of heavy and light chains from ratfish immunoglobulin.

PubMed

De Ioannes, A E; Aguila, H L

1989-01-01

The ratfish, Callorhinchus callorhinchus, a representative of the Holocephali, has a natural serum hemagglutinin (Mr 960,000), composed of heavy (Mr 71,000), light (Mr 22,500), and J (Mr 16,000) chains. To approach the mechanisms that generate diversity at this level of evolution, the amino terminal sequence of the heavy and light chains was determined by automated microsequencing. The chains are unblocked and have modest internal sequence heterogeneity. The heavy chains show sequence similarity with the terminal region of the heavy chain from the horned shark, Heterodontus francisci, and other species. In contrast to the heavy chain, the ratfish light chains display low sequence similarity with their shark kappa counterparts. However, their similarity with the variable region of the chicken lambda light chains is about 75%.
Stray Light Analysis

NASA Technical Reports Server (NTRS)

1997-01-01

Based on a Small Business Innovation Research contract from the Jet Propulsion Laboratory, TracePro is state-of-the-art interactive software created by Lambda Research Corporation to detect stray light in optical systems. An image can be ruined by incidental light in an optical system. To maintain image excellence from an optical system, stray light must be detected and eliminated. TracePro accounts for absorption, specular reflection and refraction, scattering and aperture diffraction of light. Output from the software consists of spatial irradiance plots and angular radiance plots. Results can be viewed as contour maps or as ray histories in tabular form. TracePro is adept at modeling solids such as lenses, baffles, light pipes, integrating spheres, non-imaging concentrators, and complete illumination systems. The firm's customer base includes Lockheed Martin, Samsung Electronics and other manufacturing, optical, aerospace, and educational companies worldwide.
Tables of Transition Probabilities and Branching Ratios for Electric Dipole Transitions Between Arbitrary Levels of Hydrogen-Like Atoms

NASA Technical Reports Server (NTRS)

Omidvar, K.

1980-01-01

Branching ratios in hydrogen-like atoms due to electric-dipole transitions are tabulated for the initial principal and angular momentum quantum number n, lambda, and final principal and angular momentum quantum numbers n, lambda. In table 1, transition probabilities are given for transitions n, lambda, yields n, where sums have been made with respect to lambda. In this table, 2 or = n' or = 10, o or = lambda' or = n'-1, and 1 or = n or = n'-1. In addition, averages with respect to lambda' and sums with respect to n, and lifetimes are given. In table 2, branching ratios are given for transitions n' lambda' yields ni, where sums have been made with respect to lambda. In these tables, 2 or = n' or = 10, 0 or = lambda', n'-1, and 1 or = n or = n'-1. Averages with respect to lambda' are also given. In table 3, branching ratios are given for transitions n' lambda' yields in lambda, where 1 or = n or = 5, 0 or = lambda or = n-1, n n' or = 15, and 0 or = lambda' or = n(s), where n(s), is the smaller of the two numbers n'-1 and 6. Averages with respect to lambda' are given.
Measurement of the Λ b cross section and the Λ ¯ b to Λ b ratio with J / ψ Λ decays in pp collisions at s = 7 TeV

DOE PAGES

Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; ...

2012-05-31

The Lambda(b) differential production cross section and the cross section ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Lambda(b) decays reconstructed in the exclusive final state J/Psi Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and Lambda to proton pion, using a data sample corresponding to an integrated luminosity of 1.9 inverse femtobarns. The product of the cross section times the branching ratio for Lambda(b) to J/Psi Lambda versusmore » pt(Lambda(b)) falls faster than that of b mesons. The measured value of the cross section times the branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06 +/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are statistical and systematic, respectively.« less
Heavy and Light chain amyloidosois presenting as complete heart block: A rare presentation of a rare disease.

PubMed

Priyamvada, P S; Morkhandikar, S; Srinivas, B H; Parameswaran, S

2015-01-01

Amyloidosis is an uncommon disease characterized by deposition of proteinaceous material in the extracellular matrix, which results from abnormal protein folding. Even though more than 25 precursor proteins are identified, majority of systemic amyloidosis results from deposition of abnormal immunoglobulin (Ig) light chains. In heavy chain amyloidosis (AH), deposits are derived from both heavy chain alone, whereas in heavy and light chain amyloidosis (AHL), the deposits are derived from Ig heavy chains and light chains. Both AH and AHL are extremely rare diseases. Here, we report an unusual presentation of IgG (lambda) AHL amyloidosis in the background of multiple myeloma, where the initial clinical presentation was complete heart block, which preceded the definitive diagnosis by 18 months.
First observation and measurement of the resonant structure of the lambda_b->lambda_c pi-pi+pi- decay mode

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

Azzurri, P.; Barria, P.; Ciocci, M.A.

The authors present the first observation of the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} decay using data from an integrated luminosity of approximately 2.4 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. They also present the first observation of the resonant decays {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup 0} {pi}{sup +}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup ++}{pi}{sup -}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2595){sup +}{pi}{sup -}more » {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} and {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2625){sup +}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, and measure their relative branching ratios.« less
Spin correlations in the {Lambda}{Lambda} and {Lambda}{Lambda}-bar systems generated in relativistic heavy-ion collisions

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

Lyuboshitz, V. L.; Lyuboshitz, V. V., E-mail: Valery.Lyuboshitz@jinr.r

2010-05-15

Spin correlations for the {Lambda}{Lambda} and {Lambda}{Lambda}-bar pairs, generated in relativistic heavy-ion collisions, and related angular correlations at the joint registration of hadronic decays of two hyperons, in which space parity is not conserved, are analyzed. The correlation tensor components can be derived from the double angular distribution of products of two decays by the method of 'moments'. The properties of the 'trace' of the correlation tensor (a sum of three diagonal components), determining the relative fractions of the triplet states and singlet state of respective pairs, are discussed. Spin correlations for two identical particles ({Lambda}{Lambda}) and two nonidentical particlesmore » ({Lambda}{Lambda}-bar) are considered from the viewpoint of the conventional model of one-particle sources. In the framework of this model, correlations vanish at sufficiently large relative momenta. However, under these conditions, in the case of two nonidentical particles ({Lambda}{Lambda}-bar) a noticeable role is played by two-particle annihilation (two-quark, two-gluon) sources, which lead to the difference of the correlation tensor from zero. In particular, such a situation may arise when the system passes through the 'mixed phase.'« less
Influence of Culture Medium Composition and Light Conditions on the Accumulation of Bioactive Compounds in Shoot Cultures of Scutellaria lateriflora L. (American Skullcap) Grown In Vitro.

PubMed

Kawka, Beata; Kwiecień, Inga; Ekiert, Halina

2017-12-01

Methanolic extracts from in vitro grown Scutellaria lateriflora shoots cultured on five Murashige and Skoog (MS) medium variants supplemented with different combinations of 6-benzylaminopurine (BAP) and α-naphthaleneacetic acid (NAA) under different light conditions (monochromatic light, white light and no light) were analysed by HPLC for three groups of metabolites: flavonoids (26 compounds), phenolic acids and their precursors (19+2) and phenylethanoid glycosides (2). The analyses revealed the presence of baicalein, baicalin, wogonin, wogonoside, 3,4-dihydroxyphenylacetic acid and verbascoside. There was clear evidence of the influence of plant growth regulators and light conditions on the accumulation of the analysed groups of secondary metabolites. The amounts of the compounds changed within a wide range-for the total flavonoid content, 30.2-fold (max. 1204.3 mg·100 g -1 dry weight (DW)); for 3,4-dihydroxyphenylacetic acid, 5.5-fold (max. 33.56 mg·100 g -1 DW); and for verbascoside, 1.5-fold (169.15 max. mg·100 g -1 DW). The best medium for the production of most of the compounds was the Murashige and Skoog variant with 1 mg l -1 BAP and 1 mg l -1 NAA. For verbascoside, the best 'productive' medium was the MS variant supplemented with 0.5 mg l -1 BAP and 2 mg l -1 NAA. The accumulation of the metabolites was stimulated to the greatest extent by blue light, under which the extracts were found to contain the highest total amount of flavonoids and the highest amounts of flavonoid glucuronides, baicalin and wogonoside, as well as of verbascoside. Their amounts were, respectively, 1.54-, 1.49-, 2.05- and 1.86-fold higher than under the control white light.
UTILIZING SYNTHETIC UV SPECTRA TO EXPLORE THE PHYSICAL BASIS FOR THE CLASSIFICATION OF LAMBDA BOÖTIS STARS

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

Cheng, Kwang-Ping; Johnson, Dustin M.; Tarbell, Erik S.

2016-04-15

Lambda Boo-type stars are a group of late B to early F-type Population I dwarfs that show mild to extreme deficiencies of iron-peak elements (up to 2 dex), but their C, N, O, and S abundances are near solar. This intriguing stellar class has recently regained the spotlight because of the directly imaged planets around a confirmed Lambda Boo star, HR 8799, and a suggested Lambda Boo star, Beta Pictoris. The discovery of a giant asteroid belt around Vega, another possible Lambda Boo star, also suggests hidden planets. The possible link between Lambda Boo stars and planet-bearing stars motivates usmore » to study Lambda Boo stars systematically. Since the peculiar nature of the prototype Lambda Boötis was first noticed in 1943, Lambda Boo candidates published in the literature have been selected using widely different criteria. In order to determine the origin of Lambda Boo stars’ unique abundance pattern and to better discriminate between theories explaining the Lambda Boo phenomenon, a consistent working definition of Lambda Boo stars is needed. We have re-evaluated all published Lambda Boo candidates and their available ultraviolet and visible spectra. In this paper, using observed and synthetic spectra, we explore the physical basis for the classification of Lambda Boo stars, and develop quantitative criteria that discriminate metal-poor stars from bona fide Lambda Boo stars. Based on these stricter Lambda Boo classification criteria, we conclude that neither Beta Pictoris nor Vega should be classified as Lambda Boo stars.« less
Bruton's tyrosine kinase and SLP-65 regulate pre-B cell differentiation and the induction of Ig light chain gene rearrangement.

PubMed

Kersseboom, Rogier; Ta, Van B T; Zijlstra, A J Esther; Middendorp, Sabine; Jumaa, Hassan; van Loo, Pieter Fokko; Hendriks, Rudolf W

2006-04-15

Bruton's tyrosine kinase (Btk) and the adapter protein SLP-65 (Src homology 2 domain-containing leukocyte-specific phosphoprotein of 65 kDa) transmit precursor BCR (pre-BCR) signals that are essential for efficient developmental progression of large cycling into small resting pre-B cells. We show that Btk- and SLP-65-deficient pre-B cells have a specific defect in Ig lambda L chain germline transcription. In Btk/SLP-65 double-deficient pre-B cells, both kappa and lambda germline transcripts are severely reduced. Although these observations point to an important role for Btk and SLP-65 in the initiation of L chain gene rearrangement, the possibility remained that these signaling molecules are only required for termination of pre-B cell proliferation or for pre-B cell survival, whereby differentiation and L chain rearrangement is subsequently initiated in a Btk/SLP-65-independent fashion. Because transgenic expression of the antiapoptotic protein Bcl-2 did not rescue the developmental arrest of Btk/SLP-65 double-deficient pre-B cells, we conclude that defective L chain opening in Btk/SLP-65-deficient small resting pre-B cells is not due to their reduced survival. Next, we analyzed transgenic mice expressing the constitutively active Btk mutant E41K. The expression of E41K-Btk in Ig H chain-negative pro-B cells induced 1) surface marker changes that signify cellular differentiation, including down-regulation of surrogate L chain and up-regulation of CD2, CD25, and MHC class II; and 2) premature rearrangement and expression of kappa and lambda light chains. These findings demonstrate that Btk and SLP-65 transmit signals that induce cellular maturation and Ig L chain rearrangement independently of their role in termination of pre-B cell expansion.
High precision wavefront control in point spread function engineering for single emitter localization

NASA Astrophysics Data System (ADS)

Siemons, M.; Hulleman, C. N.; Thorsen, R. Ø.; Smith, C. S.; Stallinga, S.

2018-04-01

Point Spread Function (PSF) engineering is used in single emitter localization to measure the emitter position in 3D and possibly other parameters such as the emission color or dipole orientation as well. Advanced PSF models such as spline fits to experimental PSFs or the vectorial PSF model can be used in the corresponding localization algorithms in order to model the intricate spot shape and deformations correctly. The complexity of the optical architecture and fit model makes PSF engineering approaches particularly sensitive to optical aberrations. Here, we present a calibration and alignment protocol for fluorescence microscopes equipped with a spatial light modulator (SLM) with the goal of establishing a wavefront error well below the diffraction limit for optimum application of complex engineered PSFs. We achieve high-precision wavefront control, to a level below 20 m$\\lambda$ wavefront aberration over a 30 minute time window after the calibration procedure, using a separate light path for calibrating the pixel-to-pixel variations of the SLM, and alignment of the SLM with respect to the optical axis and Fourier plane within 3 $\\mu$m ($x/y$) and 100 $\\mu$m ($z$) error. Aberrations are retrieved from a fit of the vectorial PSF model to a bead $z$-stack and compensated with a residual wavefront error comparable to the error of the SLM calibration step. This well-calibrated and corrected setup makes it possible to create complex `3D+$\\lambda$' PSFs that fit very well to the vectorial PSF model. Proof-of-principle bead experiments show precisions below 10~nm in $x$, $y$, and $\\lambda$, and below 20~nm in $z$ over an axial range of 1 $\\mu$m with 2000 signal photons and 12 background photons.
Intense excitation source of blue-green laser

NASA Astrophysics Data System (ADS)

Han, Kwang S.

1986-10-01

An intense and efficient source for blue green laser useful for the space-based satellite laser applications, underwater strategic communication, and measurement of ocean bottom profile is being developed. The source in use, the hypocycloidal pinch plasma (HCP), and the dense plasma focus (DPF) can produce intense uv photons (200 to 400nm) which match the absorption spectra of both near UV and blue green dye lasers (300 to 400nm). As a result of optimization of the DPF light at 355nm, the blue green dye (LD490) laser output exceeding 4mJ was obtained at the best cavity tunning of the laser system. With the HCP pumped system a significant enhancement of the blue green laser outputs with dye LD490 and coumarin 503 has been achieved through the spectrum conversion of the pumping light by mixing a converter dye BBQ. The maximum increase of laser output with the dye mixture of LD490+BBQ and coumarin 503+BBQ was greater than 80%. In addition, the untunned near UV lasers were also obtained. The near UV laser output energy of P-terphenyl dye was 0.5mJ at lambda sub C=337nm with the bandwidth of 3n m for the pulse duration of 0.2us. Another near UV laser output energy obtained with BBQ dye was 25 mJ at lambda sub C=383nm with the bandwidth of 3nm for the pulse duration of 0.2us. Another near UV laser output energy obtained with BBQ dye was 25 mJ at lambda sub C=383nm with the bandwidth of 3nm for the pulse duration of 0.2microsec.
Plasma markers of B-cell activation and clonality in pediatric liver and hematopoietic stem cell transplant recipients

PubMed Central

Engels, Eric A.; Savoldo, Barbara; Pfeiffer, Ruth M.; Costello, Rene; Zingone, Adriana; Heslop, Helen E.; Landgren, Ola

2012-01-01

Introduction Transplant recipients are at risk of post-transplant lymphoproliferative disease (PTLD). Methods: Thirty-six pediatric transplant recipients were evaluated (18 hematopoietic stem cell and 18 liver recipients; 12 had PTLD). We studied 207 longitudinal plasma samples from these recipients for three markers of B-cell activation or clonality: immunoglobulin free light chains (FLCs), soluble CD30 (sCD30), and monoclonal immunoglobulins (M-proteins). Results Kappa FLCs, lambda FLCs, and sCD30 were elevated in 20.8%, 28.0%, and 94.2% of plasma specimens, respectively. FLC and sCD30 levels increased significantly 1.18–1.82 fold per log10 Epstein Barr virus (EBV) load in peripheral blood. Five PTLD cases manifested elevated FLCs with an abnormal kappa/lambda ratio, suggesting monoclonal FLC production. M-proteins were present in 91% of PTLD cases, vs. 50–67% of other recipients with high or low EBV loads (p=0.13). Concordance of FLCs, M-proteins, and PTLD tumor light chain restriction was imperfect. For example, one PTLD case with an IgG lambda M-protein had a tumor that was kappa restricted, and another case with an M-protein had a T-cell PTLD. In an additional case, an IgM kappa M-protein and excess kappa FLCs were both detected in plasma at PTLD diagnosis; while the tumor was not restricted at diagnosis, kappa restriction was present 5 years later when the PTLD relapsed. Discussion Plasma markers of B-cell dysfunction are frequent following transplantation and associated with poor EBV control. These abnormal markers may be produced by oligoclonal B-cell populations or PTLD tumor cells, and could potentially help identify recipients at high risk of PTLD. PMID:23222884
Bivariate- distribution for transition matrix elements in Breit-Wigner to Gaussian domains of interacting particle systems.

PubMed

Kota, V K B; Chavda, N D; Sahu, R

2006-04-01

Interacting many-particle systems with a mean-field one-body part plus a chaos generating random two-body interaction having strength lambda exhibit Poisson to Gaussian orthogonal ensemble and Breit-Wigner (BW) to Gaussian transitions in level fluctuations and strength functions with transition points marked by lambda = lambda c and lambda = lambda F, respectively; lambda F > lambda c. For these systems a theory for the matrix elements of one-body transition operators is available, as valid in the Gaussian domain, with lambda > lambda F, in terms of orbital occupation numbers, level densities, and an integral involving a bivariate Gaussian in the initial and final energies. Here we show that, using a bivariate-t distribution, the theory extends below from the Gaussian regime to the BW regime up to lambda = lambda c. This is well tested in numerical calculations for 6 spinless fermions in 12 single-particle states.
New high-performance liquid chromatography method for the determination of (R)-warfarin and (S)-warfarin using chiral separation on a glycopeptide-based stationary phase.

PubMed

Malakova, Jana; Pavek, Petr; Svecova, Lucie; Jokesova, Iveta; Zivny, Pavel; Palicka, Vladimir

2009-10-01

Warfarin is a well-known anticoagulant agent that occurs in two enantiomers, (R)-(+)-warfarin and (S)-(-)-warfarin. A new liquid chromatography method for the determination of both enantiomers was developed, validated and applied in in vitro studies with the aim of evaluating the accumulation of (R)-warfarin and (S)-warfarin in the hepatoma HepG2 cell line. OptiMEM cell cultivation medium samples and cellular lysates were purified using Waters Oasis MAX extraction cartridges. The chiral separation of warfarin and the internal standard p-chlorowarfarin enantiomers was performed on an Astec Chirobiotic V2 column at a flow rate of 1.2mL/min. The mobile phase was composed of 31% acetonitrile, 5% of methanol and 64% of ammonium acetate buffer (10mmol/L, pH 4.1). The enantiomers were quantified using a fluorescence detector (lambda(excit)=320nm, lambda(emiss)=415nm). The limit of detection was found to be 0.121micromol/L of (S)-warfarin and 0.109micromol/L of (R)-warfarin. The range of applicability and linearity was estimated from 0.25 to 100micromol/L. The precision ranged from 1.3% to 12.2% of the relative standard deviation, and the accuracy reached acceptable values from 95.5% to 108.4%. The new bioanalytical method confirmed the same accumulation of (R)-warfarin and (S)-warfarin in the hepatoma HepG2 cell line.
Injection efficiency of bound modes. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Egalon, Claudio Oliveira

1990-01-01

Previous work on efficiency of light injection into the core of a fiber from a thin film and a bulk distribution of sources in the cladding have used the fields of a weakly guiding fiber. This approximation simplifies the analysis of the power efficiency by introducing universal values for the eigenvalues of different fibers with the same V-number, but cannot predict accurately the behavior of the injected light into a fiber with arbitrary differences in indices of refraction. The exact field solution was used in the expressions of the power efficiency, p sub eff, and its behavior as a function of the fiber parameter was analyzed. Weakly guiding results obtained previously are confirmed. However, P sub eff does not always increase with the V-number but with the difference in the indices of refraction, eta sub core-eta sub clad. For the bulk distribution it was found that P sub eff increases with the wavelength, lambda, and decreases with the fiber core radius, a, i.e., it decreases with the V-number. However, for the thin film, the P sub eff remains almost constant with lambda and the fiber core radius.
Stability engineering of anti-EGFR scFv antibodies by rational design of a lambda-to-kappa swap of the VL framework using a structure-guided approach.

PubMed

Lehmann, Andreas; Wixted, Josephine H F; Shapovalov, Maxim V; Roder, Heinrich; Dunbrack, Roland L; Robinson, Matthew K

2015-01-01

Phage-display technology facilitates rapid selection of antigen-specific single-chain variable fragment (scFv) antibodies from large recombinant libraries. ScFv antibodies, composed of a VH and VL domain, are readily engineered into multimeric formats for the development of diagnostics and targeted therapies. However, the recombinant nature of the selection strategy can result in VH and VL domains with sub-optimal biophysical properties, such as reduced thermodynamic stability and enhanced aggregation propensity, which lead to poor production and limited application. We found that the C10 anti-epidermal growth factor receptor (EGFR) scFv, and its affinity mutant, P2224, exhibit weak production from E. coli. Interestingly, these scFv contain a fusion of lambda3 and lambda1 V-region (LV3 and LV1) genes, most likely the result of a PCR aberration during library construction. To enhance the biophysical properties of these scFvs, we utilized a structure-based approach to replace and redesign the pre-existing framework of the VL domain to one that best pairs with the existing VH. We describe a method to exchange lambda sequences with a more stable kappa3 framework (KV3) within the VL domain that incorporates the original lambda DE-loop. The resulting scFvs, C10KV3_LV1DE and P2224KV3_LV1DE, are more thermodynamically stable and easier to produce from bacterial culture. Additionally, C10KV3_LV1DE and P2224KV3_LV1DE retain binding affinity to EGFR, suggesting that such a dramatic framework swap does not significantly affect scFv binding. We provide here a novel strategy for redesigning the light chain of problematic scFvs to enhance their stability and therapeutic applicability.
Correlation Measurement of Lambda-anti-Lambda, Lambda-Lambda and anti-Lambda-anti-Lambda with the ATLAS detector at s=7 TeV

NASA Astrophysics Data System (ADS)

Cheng, Hok-Chuen

This thesis summaries the measurements of correlations between Lambda 0Lambda0, Lambda0Lambda 0, and Lambda0Lambda 0 hyperon pairs produced inclusively at the LHC, which are useful for a better understanding of the quark-antiquark pair production and jet fragmentation and hadronization processes. The analysis is based on hyperon pairs selected using the muon and minimum bias data samples collected at the ATLAS experiment from proton-proton collisions at a center-of-mass energy of 7 TeV in 2010. Excess Lambda0Lambda 0 are observed near the production threshold and are identified to be originated from the parton system in the string model in the MC sample, decaying either directly or through heavy strange resonances such as Sigma0 and Sigma*(1385). Dynamical correlations have been explored through a correlation function defined as the ratio of two-particle to single-particle densities. Positive correlation is observed for Lambda0Lambda0 and anticorrelation is observed for Lambda0Lambda 0 and Lambda0Lambda 0 for Q in [0,2] GeV. The structure replicates similar correlations in pp, pp, and pppp events in PYTHIA generator as predicted by the Lund string fragmentation model. Parameters of the "popcorn" mechanism implemented in the PYTHIA generator are tuned and are found to have little impact on the structure observed. The spin composition of the sample is extracted using a data-driven reference sample built by event mixing. Appropriate corrections have been made to the kinematic distributions in the reference sample by kinematic weighting to make sure that the detector effects are well modeled. A modified Pearson's chi2 test statistics is calculated for the costheta* distribution to determine the best-fitted A-value for data. The results are consistent with zero for both like-type and unlike-type hyperon pairs in Q ∈ [0,10] GeV and Q ∈ [1,10] GeV respectively. The data statistics in the range of Q ∈ [0, 1] GeV is currently too low for the estimation of the emitter size for Fermi-Dirac correlation.
THE FAST DECLINING TYPE Ia SUPERNOVA 2003gs, AND EVIDENCE FOR A SIGNIFICANT DISPERSION IN NEAR-INFRARED ABSOLUTE MAGNITUDES OF FAST DECLINERS AT MAXIMUM LIGHT

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

Krisciunas, Kevin; Marion, G. H.; Suntzeff, Nicholas B.

2009-12-15

We obtained optical photometry of SN 2003gs on 49 nights, from 2 to 494 days after T(B {sub max}). We also obtained near-IR photometry on 21 nights. SN 2003gs was the first fast declining Type Ia SN that has been well observed since SN 1999by. While it was subluminous in optical bands compared to more slowly declining Type Ia SNe, it was not subluminous at maximum light in the near-IR bands. There appears to be a bimodal distribution in the near-IR absolute magnitudes of Type Ia SNe at maximum light. Those that peak in the near-IR after T(B {sub max})more » are subluminous in the all bands. Those that peak in the near-IR prior to T(B {sub max}), such as SN 2003gs, have effectively the same near-IR absolute magnitudes at maximum light regardless of the decline rate {delta}m {sub 15}(B). Near-IR spectral evidence suggests that opacities in the outer layers of SN 2003gs are reduced much earlier than for normal Type Ia SNe. That may allow {gamma} rays that power the luminosity to escape more rapidly and accelerate the decline rate. This conclusion is consistent with the photometric behavior of SN 2003gs in the IR, which indicates a faster than normal decline from approximately normal peak brightness.« less
X-ray clusters in a cold dark matter + lambda universe: A direct, large-scale, high-resolution, hydrodynamic simulation

NASA Technical Reports Server (NTRS)

Cen, Renyue; Ostriker, Jeremiah P.

1994-01-01

A new, three-dimensional, shock-capturing, hydrodynamic code is utilized to determine the distribution of hot gas in a cold dark matter (CDM) + lambda model universe. Periodic boundary conditions are assumed: a box with size 85/h Mpc, having cell size 0.31/h Mpc, is followed in a simulation with 270(exp 3) = 10(exp 7.3) cells. We adopt omega = 0.45, lambda = 0.55, h identically equal to H/100 km/s/Mpc = 0.6, and then, from the cosmic background explorer (COBE) and light element nucleosynthesis, sigma(sub 8) = 0.77, omega(sub b) = 0.043. We identify the X-ray emitting clusters in the simulation box, compute the luminosity function at several wavelength bands, the temperature function and estimated sizes, as well as the evolution of these quantities with redshift. This open model succeeds in matching local observations of clusters in contrast to the standard omega = 1, CDM model, which fails. It predicts an order of magnitude decline in the number density of bright (h nu = 2-10 keV) clusters from z = 0 to z = 2 in contrast to a slight increase in the number density for standard omega = 1, CDM model. This COBE-normalized CDM + lambda model produces approximately the same number of X-ray clusters having L(sub x) greater than 10(exp 43) erg/s as observed. The background radiation field at 1 keV due to clusters is approximately the observed background which, after correction for numerical effects, again indicates that the model is consistent with observations.

He II lambda-4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region During Periastron Passage

NASA Technical Reports Server (NTRS)

Teodoro, M.; Damineli, A.; Arias, J. I.; DeAraujo, F. X.; Barba, R. H.; Corcoran, M. F.; Fernandes, M. Borges; Fernandez-Lajus, E.; Fraga, L.; Gamen, R. C.;

2012-01-01

The periodic spectroscopic events in Eta Carinae are now well established and occur near the periastron passage of two massive stars in a very eccentric orbit. Several mechanisms have been proposed to explain the variations of different spectral features, such as an eclipse by the wind-wind collision boundary, a shell ejection from the primary star or accretion of its wind onto the secondary. All of them have problems explaining all the observed phenomena. To better understand the nature of the cyclic events we performed a dense monitoring of Eta Carinae with 5 Southern telescopes during the 2009 low excitation event, resulting in a set of data of unprecedented quality and sampling. The intrinsic luminosity of the He II lambda-4686 emission line (L approx 310 solar L) just before periastron reveals the presence of a very luminous transient source of extreme UV radiation emitted in the wind-wind collision (WWC) region. Clumps in the primary's wind probably explain the flare-like behavior of both the X-ray and He II lambda-4686 light-curves. After a short-lived minimum, He II lambda-4686 emission rises again to a new maximum, when X-rays are still absent or very weak. We interpret this as a collapse of the WWC onto the "surface" of the secondary star, switching off the hard X-ray source and diminishing the WWC shock cone. The recovery from this state is controlled by the momentum balance between the secondary's wind and the clumps in the primary's wind.

The two photocycles of photoactive yellow protein from Rhodobacter sphaeroides.

PubMed

Haker, Andrea; Hendriks, Johnny; van Stokkum, Ivo H M; Heberle, Joachim; Hellingwerf, Klaas J; Crielaard, Wim; Gensch, Thomas

2003-03-07

The absorption spectrum of the photoactive yellow protein from Rhodobacter sphaeroides (R-PYP) shows two maxima, absorbing at 360 nm (R-PYP(360)) and 446 nm (R-PYP(446)), respectively. Both forms are photoactive and part of a temperature- and pH-dependent equilibrium (Haker, A., Hendriks, J., Gensch, T., Hellingwerf, K. J., and Crielaard, W. (2000) FEBS Lett. 486, 52-56). At 20 degrees C, for PYP characteristic, the 446-nm absorbance band displays a photocycle, in which the depletion of the 446-nm ground state absorption occurs in at least three phases, with time constants of <30 ns, 0.5 micros, and 17 micros. Intermediates with both blue- and red-shifted absorption maxima are transiently formed, before a blue-shifted intermediate (pB(360), lambda(max) = 360 nm) is established. The photocycle is completed with a monophasic recovery of the ground state with a time constant of 2.5 ms. At 7 degrees C these photocycle transitions are slowed down 2- to 3-fold. Upon excitation of R-PYP(360) with a UV-flash (330 +/- 50 nm) a species with a difference absorption maximum at approximately 435 nm is observed that returns to R-PYP(360) on a minute time scale. Recovery can be accelerated by a blue light flash (450 nm). R-PYP(360) and R-PYP(446) differ in their overall protein conformation, as well as in the isomerization and protonation state of the chromophore, as determined with the fluorescent polarity probe Nile Red and Fourier Transform Infrared spectroscopy, respectively.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Akaishi, Yoshinori; College of Science and Technology, Nihon University, Funabashi 274-8501; Myint, Khin Swe

The overbinding problem of {sub {lambda}}{sup 5}He is solved by introducing a concept of coherent {lambda}-{sigma} coupling which is equivalent to a {lambda}NN three-body force. This three-body force is coherently enhanced in the 0{sup +} states of {sub {lambda}}{sup 4}H and {sub {lambda}}{sup 4}He. The 0{sup +}-1{sup +} splitting in these hypernuclei is mainly due to coherent {lambda}-{sigma} coupling and partly due to the {lambda}N spin-spin interaction. A {lambda}NN three-body potential is derived from the coupled-channel treatment. The origin of the repulsive and attractive nature of the three-body force is discussed. Coherent {lambda}-{sigma} coupling becomes more important in neutron-rich hypernucleimore » and especially in neutron-star matter at high densities. The possible existence of ''hyperheavy hydrogen'', {sub {lambda}}{sup 6}H, is suggested.« less
Spectrophotometric determination of phenylephrine HCl and orphenadrine citrate in pure and in dosage forms.

PubMed

Shama, S A

2002-11-07

A simple and rapid spectrophotometric methods have been estimated for the microdetermination of phenylephrine HCl (I) and orphenadrine citrate (II). The proposed methods are based on the formation of ion-pair complexes between the examined drugs with alizarine (Aliz), alizarine red S (ARS), alizarine yellow G (AYG) or quinalizarine (Qaliz), which can be measured at the optimum lambda(max). The optimization of the reaction conditions is investigated. Beer's law is obeyed in the concentration ranges 2-36 microgram ml(-1), whereas optimum concentration as adopted from Ringbom plots was 3.5-33 microgram ml(-1). The molar absorptivity, Sandell sensitivity, and detection limit are also calculated. The correlation coefficient was >/=0.9988 (n=6) with a relative standard deviation of
Role of the Escherichia coli grpE heat shock protein in the initiation of bacteriophage lambda DNA replication.

PubMed

Osipiuk, J; Zylicz, M

1991-01-01

Initiation of replication of lambda DNA requires assembly of the proper nucleoprotein complex consisting of the lambda origin of replication-lambda O-lambda P-dnaB proteins. The dnaJ, dnaK and grpE heat shock proteins destabilize the lambda P-dnaB interaction in this complex permitting dnaB helicase to unwind lambda DNA near ori lambda sequence. First step of this disassembling reaction is the binding of dnaK protein to lambda P protein. In this report we examined the influence of dnaJ and grpE proteins on stability of the lambda P-dnaK complex. Our results show that grpE alone dissociates this complex, but both grpE and dnaJ together do not. These results suggest that, in the presence of grpE protein, dnaK protein has a higher affinity for lambda P protein complexed with dnaJ protein than in the situation where grpE protein is not used.
Measurement of sigma Lambda b0/sigma B0 x B(Lambda b0-->Lambda c+pi-)/B(B0-->D+pi-) in pp collisions at square root s=1.96 TeV.

PubMed

Abulencia, A; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arguin, J-F; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Budroni, S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carillo, S; Carlsmith, D; Carosi, R; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciljak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Cyr, D; DaRonco, S; D'Auria, S; Davies, T; D'Onofrio, M; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; Dell'Orso, M; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; DiTuro, P; Dörr, C; Donati, S; Donega, M; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Griffiths, M; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jensen, H; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kovalev, A; Kraan, A C; Kraus, J; Kravchenko, I; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; Le, Y; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Manca, G; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Nachtman, J; Nagano, A; Naganoma, J; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nigmanov, T; Nodulman, L; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Osterberg, K; Pagliarone, C; Palencia, E; Papadimitriou, V; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ranjan, N; Rappoccio, S; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Sabik, S; Safonov, A; Sakumoto, W K; Salamanna, G; Saltó, O; Saltzberg, D; Sánchez, C; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyrla, A; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Sjolin, J; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tseng, J; Tsuchiya, R; Tsuno, S; Turini, N; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Veramendi, G; Veszpremi, V; Vidal, R; Vila, I; Vilar, R; Vine, T; Vollrath, I; Volobouev, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, J; Wagner, W; Wallny, R; Wang, S M; Warburton, A; Waschke, S; Waters, D; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zhou, J; Zucchelli, S

2007-03-23

We present the first observation of the baryon decay Lambda b0-->Lambda c+pi- followed by Lambda c+-->pK-pi+ in 106 pb-1 pp collisions at square root s=1.96 TeV in the CDF experiment. In order to reduce systematic error, the measured rate for Lambda b0 decay is normalized to the kinematically similar meson decay B0-->D+pi- followed by D+-->pi+K-pi+. We report the ratio of production cross sections (sigma) times the ratio of branching fractions (B) for the momentum region integrated above pT>6 GeV/c and pseudorapidity range |eta|<1.3: sigma(pp-->Lambda b0X)/sigma(pp-->B0X)xB(Lambda b0-->Lambda c+pi-)/B(B0-->D+pi-)=0.82+/-0.08(stat)+/-0.11(syst)+/-0.22[B(Lambda c+-->pK-pi+)].
Stable carbon isotope fractionation during the biodegradation of lambda-cyhalothrin.

PubMed

Shen, Xiaoli; Xu, Zemin; Zhang, Xichang; Yang, Fangxing

2015-11-01

In this study, the microbial degradation of lambda-cyhalothrin in soil was investigated using compound-specific stable isotope analysis. The results revealed that lambda-cyhalothrin was biodegraded in soil under laboratory conditions. The half-lives of lambda-cyhalothrin were determined to be 49 and 161 days in non-sterile and sterile soils spiked with 2mg/kg lambda-cyhalothrin and 84 and 154 days in non-sterile and sterile soils spiked with 10mg/kg lambda-cyhalothrin, respectively. The biodegradation of lambda-cyhalothrin resulted in carbon isotope fractionation, which shifted from -29.0‰ to -26.5‰ in soil spiked with 2mg/kg lambda-cyhalothrin, and to -27.5‰ with 10mg/kg lambda-cyhalothrin. A relationship was established between the stable carbon isotope fraction and the residual concentrations of lambda-cyhalothrin by the Rayleigh equation in which the carbon isotope enrichment factor ε of the microbial degradation of lambda-cyhalothrin in the soil was calculated as -2.53‰. This study provides an approach to quantitatively evaluate the biodegradation of lambda-cyhalothrin in soil in field studies. Copyright © 2015 Elsevier B.V. All rights reserved.
Dynamics of a family of transcendental meromorphic functions having rational Schwarzian derivative

NASA Astrophysics Data System (ADS)

Sajid, M.; Kapoor, G. P.

2007-02-01

In the present paper, a class of critically finite transcendental meromorphic functions having rational Schwarzian derivative is introduced and the dynamics of functions in one parameter family is investigated. It is found that there exist two parameter values [lambda]*=[phi](0)>0 and , where and is the real root of [phi]'(x)=0, such that the Fatou sets of f[lambda](z) for [lambda]=[lambda]* and [lambda]=[lambda]** contain parabolic domains. A computationally useful characterization of the Julia set of the function f[lambda](z) as the complement of the basin of attraction of an attracting real fixed point of f[lambda](z) is established and applied for the generation of the images of the Julia sets of f[lambda](z). Further, it is observed that the Julia set of explodes to whole complex plane for [lambda]>[lambda]**. Finally, our results found in the present paper are compared with the recent results on dynamics of one parameter families [lambda]tanz, [R.L. Devaney, L. Keen, Dynamics of meromorphic maps: Maps with polynomial Schwarzian derivative, Ann. Sci. Ecole Norm. Sup. 22 (4) (1989) 55-79; L. Keen, J. Kotus, Dynamics of the family [lambda]tan(z), Conform. Geom. Dynam. 1 (1997) 28-57; G.M. Stallard, The Hausdorff dimension of Julia sets of meromorphic functions, J. London Math. Soc. 49 (1994) 281-295] and , [lambda]>0 [G.P. Kapoor, M. Guru Prem Prasad, Dynamics of : The Julia set and bifurcation, Ergodic Theory Dynam. Systems 18 (1998) 1363-1383].
Endorsing the declining indigenous ethnobotanical knowledge system of seabuckthorn in Central Himalaya, India.

PubMed

Dhyani, D; Maikhuri, R K; Misra, S; Rao, K S

2010-02-03

Based on research findings this study is aimed to generate database on ethnobotanical aspects, sustainable utilization by value addition and awareness generation through outreach programme related to Hippophae salicifolia D. Don. (Elaeagnaceae) in the higher Himalayan zone of Uttarakhand in Central Himalaya, India. An in-depth survey from June 2004 to July 2006 followed by 480 interviews with the help of semi-structured questionnaires was carried out in 24 Hippophae growing locations in 12 different valleys of Uttarakhand. Plant has immense multipurpose properties and is traditionally utilized for food (20(Min)-90%(Max)), medicine (10(Min)-60%(Max)), veterinary (20(Min)-100%(Max)), fuel (10(Min)-80%(Max)), fencing (20(Min)-80%(Max)), agricultural tools (20(Min)-50%(Max)) and dye mordant (60%). Besides, awareness programmes and value added product demonstration resulted in economical upliftment of local inhabitants of Central Himalaya. The present manuscript will certainly provide an ethnobotanical statistics' impact on the modern scientific societies regarding conservation, cultivation and popularization of this underutilized wild edible species at mass scale. Simultaneously, these findings have important connotations in light of upcoming organic food and nutraceutical industries in the country. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.
Complex of a Protective Antibody with its Ebola Virus GP Peptide Epitope: Unusual Features of a V lambda x Light Chain

DTIC Science & Technology

2007-10-01

twists. Bioinformatics, 19, ii246–ii255. 52. Lawrence, M. C. & Colman, P. M. (1993). Shape complementarity at protein / protein interfaces . J. Mol. Biol...envelope spike, which is the sole protein expressed on the surface of the Ebola virus and is involved in receptor binding, tropism, and viral entry.6–9 It...26 At the variable light chain/heavy chain (VL/VH) interface of 13F6-1-2, ∼1025 Å2 surface area is buried on VL Fig. 1. Nucleotide and translated amino
Propagation of laser beams in scattering media.

PubMed

Zuev, V E; Kabanov, M V; Savelev, B A

1969-01-01

Experimental investigations have been undertaken of some aspects of the propagation of helium-neon gas laser radiation at lambda = 0.63 micro for different scattering media (artificial water fogs, wood smokes, model media). It has been shown that the attenuation coefficients practically coincide when coherent and incoherent radiation is scattered. The applicability limits of Bouguer-Beer's law for describing the attenuation of radiation in scattering media are investigated and the intensity of multiple forward-scattered light for different geometrical parameters of the source and radiation receiver are measured. The applicability of single scattering theory formulas for describing forward-scattered light intensity are discussed.
Jovian Chromophore Characteristics from Multispectral HST Images

NASA Technical Reports Server (NTRS)

Strycker, Paul D.; Chanover, Nancy J.; Simon-Miller, Amy A.; Banfield, Don; Gierasch, Peter J.

2011-01-01

The chromophores responsible for coloring the jovian atmosphere are embedded within Jupiter's vertical aerosol structure. Sunlight propagates through this vertical distribution of aerosol particles, whose colors are defined by omega-bar (sub 0)(lambda), and we remotely observe the culmination of the radiative transfer as I/F(lambda). In this study, we employed a radiative transfer code to retrieve omega-bar (sub 0)(lambda) for particles in Jupiter's tropospheric haze at seven wavelengths in the near-UV and visible regimes. The data consisted of images of the 2008 passage of Oval BA to the south of the Great Red Spot obtained by the Wide Field Planetary Camera 2 on-board the Hubble Space Telescope. We present derived particle colors for locations that were selected from 14 weather regions, which spanned a large range of observed colors. All omega-bar (sub 0)(lambda) curves were absorbing in the blue, and omega-bar (sub 0)(lambda) increased monotonically to approximately unity as wavelength increased. We found accurate fits to all omega-bar (sub 0)(lambda) curves using an empirically derived functional form: omega-bar (sub 0)(lambda) = 1 A exp(-B lambda). The best-fit parameters for the mean omega-bar (sub 0)(lambda) curve were A = 25.4 and B = 0.0149 for lambda in units of nm. We performed a principal component analysis (PCA) on our omega-bar (sub 0)(lambda) results and found that one or two independent chromophores were sufficient to produce the variations in omega-bar (sub 0)(lambda). A PCA of I/F(lambda) for the same jovian locations resulted in principal components (PCs) with roughly the same variances as the omega-bar (sub 0)(lambda) PCA, but they did not result in a one-to-one mapping of PC amplitudes between the omega-bar (sub 0)(lambda) PCA and I/F(lambda) PCA. We suggest that statistical analyses performed on I/ F(lambda) image cubes have limited applicability to the characterization of chromophores in the jovian atmosphere due to the sensitivity of 1/ F(lambda) to horizontal variations in the vertical aerosol distribution.
Mechanisms of Hyperbilirubinemia During Peginterferon Lambda-1a Therapy for Chronic Hepatitis C Infection: A Retrospective Investigation.

PubMed

Zwirtes, Ricardo; Narasimhan, Premkumar; Wind-Rotolo, Megan M; Xu, Dong; Hruska, Matthew W; Kishnani, Narendra; Colston, Elizabeth M; Srinivasan, Subasree

2016-11-01

The phase 2b EMERGE study compared the efficacy/safety of peginterferon lambda-1a (Lambda) and peginterferon alfa-2a (Alfa), both with ribavirin (RBV), for treatment of chronic hepatitis C virus (HCV) infection. A key safety finding was a higher frequency of hyperbilirubinemia with Lambda/RBV versus Alfa/RBV. To characterize mechanisms of hyperbilirubinemia associated with Lambda/RBV, we conducted a retrospective analysis of safety data from the HCV genotype 1 and genotype 4 cohort of the EMERGE study. Subjects were randomized to once-weekly Lambda (120/180/240 μg) or Alfa (180 μg), with daily RBV, for 48 weeks. Early-onset Lambda/RBV-related hyperbilirubinemia events (6-12 weeks) resulted mostly from RBV-induced hemolysis evidenced by sustained reticulocytosis and a predominantly unconjugated pattern of hyperbilirubinemia. The higher hyperbilirubinemia frequency with Lambda/RBV versus Alfa/RBV was attributed to bone marrow suppression known to occur with Alfa but not Lambda. Late-onset (>12 weeks) Lambda/RBV-related hyperbilirubinemia events occurred most frequently with higher Lambda doses and were associated with increased levels of hepatic transaminase and direct bilirubin fractions compared with early events. This dual pattern of hyperbilirubinemia observed while on Lambda/RBV treatment is thought to be caused by exaggerated RBV-induced hemolysis in early-onset events compared with possible direct Lambda-induced hepatocellular toxicity in late-onset events.
Demonstration of Broadband Contrast at 1.2 Lambda/D for the EXCEDE Phase-Induced Amplitude Apodization Coronagraph

NASA Technical Reports Server (NTRS)

Sirbu, Dan; Thomas, Sandrine J.; Belikov, Ruslan; Lozi, Julien; Bendek, Eduardo; Pluzhnik, Eugene; Lynch, Dana H.; Hix, Troy; Zell, Peter; Schneider, Glenn;

2015-01-01

The proposed coronagraph instrument on the EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer) mission study uses a Phase-Induced Amplitude Apodization (PIAA) coronagraph architecture to enable high-contrast imaging of circumstellar debris disks and giant planets at angular separations as close in as the habitable zone of nearby host stars. We report on the experimental results obtained in the vacuum chamber at the Lockheed Martin Advanced Technology Center in 10 percent broadband light centered about 650 nanometers, with a median contrast of 1 x 10 (sup -5) between 1.2 and 2.0 lambda /D simultaneously with 3 x 10 (sup -7) contrast between 2 and 11 =D between 2 and 11 lambda/D for a single-sided dark hole using a deformable mirror (DM) upstream of the PIAA coronagraph. The results are stable and repeatable as demonstrated by three measurements runs with DM settings set from scratch and maintained on the best 90 percent out of the 1000 collected frames. We compare the reduced experimental data with simulation results from modeling observed experimental limits; performance is consistent with uncorrected low-order modes not estimated by the Low Order Wavefront Sensor (LOWFS). Modeled sensitivity to bandwidth and residual tip/tilt modes is well-matched to the experiment.

SN 1994I in M51 and the nature of type Ibc supernovae

NASA Technical Reports Server (NTRS)

Wheeler, J. C.; Harkness, R. P.; Clocchiatti, A.; Benetti, S.; Brotherton, M. S.; Depoy, D. L.; Elias, J.

1994-01-01

Early spectra of SN 1994I in M51 (NGC 5194) are presented along with arguments that is a member of the class of helium-poor Type Ic supernovae. The issue of H and He in the spectra of Type Ib and Ic events is reexamined with the conclusion that Type Ib eject substantially less H than even transition events like SN 1993J and that Type Ic eject substantially less He than Type Ib and their optical spectra are consistent with no H or He. Type Ic show and absorption of the Si II lambda 6355 blend that characterizes Type Ia. This feature requires only a solar abundance of Si. Some Type Ic show an absorption that is probably C II lambda 6580. IR spectra are presented of SN 1990W which show the line of He I lambda 10830. The strength of this feature and the rather slow decay of the late time light curve suggest that this event could be better classified as a Type Ib. Even if trace abundances of H are present in Type Ib and of He in Type Ic the spectral differences still imply a distinctly different evolution for the progenitors of Type Ib from Type Ic and events like SN 1993J.
Visible light emitting vertical cavity surface emitting lasers

DOEpatents

Bryan, Robert P.; Olbright, Gregory R.; Lott, James A.; Schneider, Jr., Richard P.

1995-01-01

A vertical cavity surface emitting laser that emits visible radiation is built upon a substrate, then having mirrors, the first mirror on top of the substrate; both sets of mirrors being a distributed Bragg reflector of either dielectrics or other materials which affect the resistivity or of semiconductors, such that the structure within the mirror comprises a plurality of sets, each having a thickness of .lambda./2n where n is the index of refraction of each of the sets; each of the mirrors adjacent to spacers which are on either side of an optically active bulk or quantum well layer; and the spacers and the optically active layer are from one of the following material systems: In.sub.z (Al.sub.y Ga.sub.1-y).sub.1-z P, InAlGaAs, AlGaAs, InGaAs, or AlGaP/GaP, wherein the optically active region having a length equal to m .lambda./2n.sub.eff where m is an integer and n.sub.eff is the effective index of refraction of the laser cavity, and the spacer layer and one of the mirrors being transmissive to radiation having a wavelength of .lambda./n, typically within the green to red portion of the visible spectrum.
Visible light emitting vertical cavity surface emitting lasers

DOEpatents

Bryan, R.P.; Olbright, G.R.; Lott, J.A.; Schneider, R.P. Jr.

1995-06-27

A vertical cavity surface emitting laser that emits visible radiation is built upon a substrate, then having mirrors, the first mirror on top of the substrate; both sets of mirrors being a distributed Bragg reflector of either dielectrics or other materials which affect the resistivity or of semiconductors, such that the structure within the mirror comprises a plurality of sets, each having a thickness of {lambda}/2n where n is the index of refraction of each of the sets; each of the mirrors adjacent to spacers which are on either side of an optically active bulk or quantum well layer; and the spacers and the optically active layer are from one of the following material systems: In{sub z}(Al{sub y}Ga{sub 1{minus}y}){sub 1{minus}z}P, InAlGaAs, AlGaAs, InGaAs, or AlGaP/GaP, wherein the optically active region having a length equal to m {lambda}/2n{sub eff} where m is an integer and n{sub eff} is the effective index of refraction of the laser cavity, and the spacer layer and one of the mirrors being transmissive to radiation having a wavelength of {lambda}/n, typically within the green to red portion of the visible spectrum. 10 figs.
Visible light surface emitting semiconductor laser

DOEpatents

Olbright, Gregory R.; Jewell, Jack L.

1993-01-01

A vertical-cavity surface-emitting laser is disclosed comprising a laser cavity sandwiched between two distributed Bragg reflectors. The laser cavity comprises a pair of spacer layers surrounding one or more active, optically emitting quantum-well layers having a bandgap in the visible which serve as the active optically emitting material of the device. The thickness of the laser cavity is m .lambda./2n.sub.eff where m is an integer, .lambda. is the free-space wavelength of the laser radiation and n.sub.eff is the effective index of refraction of the cavity. Electrical pumping of the laser is achieved by heavily doping the bottom mirror and substrate to one conductivity-type and heavily doping regions of the upper mirror with the opposite conductivity type to form a diode structure and applying a suitable voltage to the diode structure. Specific embodiments of the invention for generating red, green, and blue radiation are described.
Generating high-current monoenergetic proton beams by a circularly polarized laser pulse in the phase-stable acceleration regime.

PubMed

Yan, X Q; Lin, C; Sheng, Z M; Guo, Z Y; Liu, B C; Lu, Y R; Fang, J X; Chen, J E

2008-04-04

A new ion acceleration method, namely, phase-stable acceleration, using circularly-polarized laser pulses is proposed. When the initial target density n(0) and thickness D satisfy a(L) approximately (n(0)/n(c))D/lambda(L) and D>l(s) with a(L), lambda(L), l(s), and n(c) the normalized laser amplitude, the laser wavelength in vacuum, the plasma skin depth, and the critical density of the incident laser pulse, respectively, a quasiequilibrium for the electrons is established by the light pressure and the space charge electrostatic field at the interacting front of the laser pulse. The ions within the skin depth of the laser pulse are synchronously accelerated and bunched by the electrostatic field, and thereby a high-intensity monoenergetic proton beam can be generated. The proton dynamics is investigated analytically and the results are verified by one- and two-dimensional particle-in-cell simulations.
Existence and non-uniqueness of similarity solutions of a boundary-layer problem

NASA Technical Reports Server (NTRS)

Hussaini, M. Y.; Lakin, W. D.

1986-01-01

A Blasius boundary value problem with inhomogeneous lower boundary conditions f(0) = 0 and f'(0) = - lambda with lambda strictly positive was considered. The Crocco variable formulation of this problem has a key term which changes sign in the interval of interest. It is shown that solutions of the boundary value problem do not exist for values of lambda larger than a positive critical value lambda. The existence of solutions is proven for 0 lambda lambda by considering an equivalent initial value problem. It is found however that for 0 lambda lambda, solutions of the boundary value problem are nonunique. Physically, this nonuniqueness is related to multiple values of the skin friction.

Existence and non-uniqueness of similarity solutions of a boundary layer problem

NASA Technical Reports Server (NTRS)

Hussaini, M. Y.; Lakin, W. D.

1984-01-01

A Blasius boundary value problem with inhomogeneous lower boundary conditions f(0) = 0 and f'(0) = - lambda with lambda strictly positive was considered. The Crocco variable formulation of this problem has a key term which changes sign in the interval of interest. It is shown that solutions of the boundary value problem do not exist for values of lambda larger than a positive critical value lambda. The existence of solutions is proven for 0 lambda lambda by considering an equivalent initial value problem. It is found however that for 0 lambda lambda, solutions of the boundary value problem are nonunique. Physically, this nonuniqueness is related to multiple values of the skin friction.
Measurement of the Lambda b0 lifetime in Lambda b0-->J/psi Lambda 0 in pp collisions at square root s=1.96 TeV.

PubMed

Abulencia, A; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arguin, J-F; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Budroni, S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carrillo, S; Carlsmith, D; Carosi, R; Carron, S; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciljak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Cyr, D; DaRonco, S; D'Auria, S; Davies, T; D'Onofrio, M; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; Dell'Orso, M; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; DiTuro, P; Dörr, C; Donati, S; Donega, M; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Griffiths, M; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jensen, H; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kovalev, A; Kraan, A C; Kraus, J; Kravchenko, I; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kusakabe, Y; Kwang, S; Laasanen, A T; Labarga, L; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Liss, T M; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Manca, G; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Nachtman, J; Nagano, A; Naganoma, J; Nahn, S; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nigmanov, T; Nodulman, L; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Osterberg, K; Pagliarone, C; Palencia, E; Papadimitriou, V; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prokoshin, F; Pronko, A; Proudfoot, J; Ptochos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ranjan, N; Rappoccio, S; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Sabik, S; Safonov, A; Sakumoto, W K; Salamanna, G; Saltó, O; Saltzberg, D; Sánchez, C; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyrla, A; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Sjolin, J; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Tesarek, R J; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tsuchiya, R; Tsuno, S; Turini, N; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Veramendi, G; Veszpremi, V; Vidal, R; Vila, I; Vilar, R; Vine, T; Vollrath, I; Volobouev, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, J; Wagner, W; Wallny, R; Wang, S M; Warburton, A; Waschke, S; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zhou, J; Zucchelli, S

2007-03-23

We report a measurement of the Lambda b0 lifetime in the exclusive decay Lambda b0-->J/psi Lambda 0 in pp collisions at square root s=1.96 TeV using an integrated luminosity of 1.0 fb-1 of data collected by the CDF II detector at the Fermilab Tevatron. Using fully reconstructed decays, we measure tau(Lambda b0)=1.593(-0.078)(+0.083)(stat)+/-0.033(syst) ps. This is the single most precise measurement of tau(Lambda b0) and is 3.2sigma higher than the current world average.
Observation of the baryonic B decay B{sup 0}{yields}{Lambda}{sub c}{sup +}{Lambda}K{sup -}

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

Lees, J. P.; Poireau, V.; Tisserand, V.

2011-10-01

We report the observation of the baryonic B decay B{sup 0}{yields}{Lambda}{sub c}{sup +}{Lambda}K{sup -} with a significance larger than 7 standard deviations based on 471x10{sup 6} BB pairs collected with the BABAR detector at the PEP-II storage ring at SLAC. We measure the branching fraction for the decay B{sup 0}{yields}{Lambda}{sub c}{sup +}{Lambda}K{sup -} to be (3.8{+-}0.8{sub stat}{+-}0.2{sub sys}{+-}1.0{sub {Lambda}}{sub c}{sup +})x10{sup -5}. The uncertainties are statistical, systematic, and due to the uncertainty in the {Lambda}{sub c}{sup +} branching fraction. We find that the {Lambda}{sub c}{sup +}K{sup -} invariant-mass distribution shows an enhancement above 3.5 GeV/c{sup 2}.
Doublet-spacing enhancement caused by {Lambda}N-{Sigma}N coupling in {sub {Lambda}L}i hypernuclear isotopes

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

Umeya, Atsushi; Harada, Toru; Research Center for Physics and Mathematics, Osaka Electro-Communication University, Neyagawa, Osaka 572-8530

2011-03-15

We theoretically investigate energy spacings of doublets in {sub {Lambda}L}i hypernuclear isotopes with A=7-10 in shell-model calculations with a {Lambda}N-{Sigma}N coupling effect. The calculated results show that the energy shifts are {Delta}{epsilon}=0.09-0.28 MeV and the {Sigma}-mixing probabilities are P{sub {Sigma}}=0.10%-0.34% in {Lambda} ground states for the isotopes because of the {Lambda}N-{Sigma}N coupling in the first-order perturbation. It is found that the energy spacing of the doublet is enhanced as a neutron number N increases; the contribution of the {Lambda}N-{Sigma}N coupling interaction is comparable to that of the {Lambda}N interaction in the neutron-rich {Lambda} hypernuclei. The coherent mechanism of this doublet-spacingmore » enhancement is also discussed in terms of Fermi-type and Gamow-Teller-type {Lambda}N-{Sigma}N couplings.« less
The role of template superhelicity in the initiation of bacteriophage lambda DNA replication.

PubMed Central

Alfano, C; McMacken, R

1988-01-01

The prepriming steps in the initiation of bacteriophage lambda DNA replication depend on the action of the lambda O and P proteins and on the DnaB helicase, single-stranded DNA binding protein (SSB), and DnaJ and DnaK heat shock proteins of the E. coli host. The binding of multiple copies of the lambda O protein to the phage replication origin (ori lambda) initiates the ordered assembly of a series of nucleoprotein structures that form at ori lambda prior to DNA unwinding, priming and DNA synthesis steps. Since the initiation of lambda DNA replication is known to occur only on supercoiled templates in vivo and in vitro, we examined how the early steps in lambda DNA replication are influenced by superhelical tension. All initiation complexes formed prior to helicase-mediated DNA-unwinding form with high efficiency on relaxed ori lambda DNA. Nonetheless, the DNA templates in these structures must be negatively supertwisted before they can be replicated. Once DNA helicase unwinding is initiated at ori lambda, however, later steps in lambda DNA replication proceed efficiently in the absence of superhelical tension. We conclude that supercoiling is required during the initiation of lambda DNA replication to facilitate entry of a DNA helicase, presumably the DnaB protein, between the DNA strands. Images PMID:2847118
Multiple myeloma invasion of the central nervous system.

PubMed

Marjanović, Slobodan; Mijusković, Zoran; Stamatović, Dragana; Madjaru, Lavinika; Ralić, Tijana; Trimcev, Jovana; Stojanović, Jelica; Radović, Vesna

2012-02-01

Multiple myeloma (MM) is characterized by the presence of neoplastic proliferating plasma cells. The tumor is generally restricted to the bone marrow. The most common complications include renal insufficiency, hypercalcemia, anemia and reccurent infections. The spectrum of MM neurological complications is diverse, however, involvement of MM in the cerebrospinal fluid (CSF) and leptomeningeal infiltration are rare considered. In about 1% of the cases, the disease affects the central nervous system (CNS) and presents itself in the form of localized intraparenchymal lesions, solitary cerebral plasmocytoma or CNS myelomatosis (LMM). We presented the clinical course of a 55-year-old man with MM and LMM proven by malignant plasma cells in the CSF, hospitalized with the pain in the thoracic spine. His medical history was uneventful. There had been no evidence of mental or neurological impairment prior to the seizures. Physical examination showed no abnormalities. After a complete staging, the diagnosis of MM type biclonal gammopathia IgG lambda and free lambda light chains in the stage III was confirmed. The treatment started with systemic chemotherapy (with vincristine, doxorubicin plus high-dose dexamethasone--VAD protocol), radiotherapy and bisphosphonate. The patient developed weakness, nausea, febrility, dispnea, bilateral bronchopneumonia, acute renal insufficiency, confusions, headaches and soon thereafter sensomotor aphasias and right hemiparesis. The patient was treated with the adequate therapy including one hemodyalisis. His neurological status was deteriorated, so Multislice Computed Tomography (MSCT) of the head was performed and the findings were normal. Analysis of CSF showed pleocytosis, 26 elements/mL and increased concentrations of proteins. Cytological analysis revealed an increased number of plasma cells (29%). Electrophoretic analysis of proteins disclosed the existance of monoclonal components in the serum, urine and CSF. Immunofixation electrophoretic and quantitative nephelometric tests confirmed Biclonal multiple myeloma of IgG lambda and light chain lambda isotypes. Analysis of neurothropic viruses with ELISA methods was negative. Once the presence of LMM was confirmed, the patient received intrathecal chemotherapy with methotrexate, cytosine arabinoside, dexamethasone three times a week, and systemic high doses of dexamethasone iv like a single agent without craniospinale irradiations. Despite the treatment, the patient died one month after the diagnosis. Autopsy was not performed. Presented patient, as well as most other patients with MM progressing to CN Sinfiltration was in the stage III. In addition to the detailed clinical examination, and all investigations required for MM diagnosis and staging of the disease, we introduced the additional CSF examination and calculation of kappa lambda ratio, that helped us make an early diagnosis and prognosis of MM with LMM. Although LMM had a low prevalence, it could be more frequent than expected especially in patients with high risk. CSF examination with positive plasma cells and abnormal morphology remains the hallmark for diag nosing CNS infiltration.
Galaxy formation in Lambda greater than 0 Friedmann models: Consequences for the number counts versus redshift test

NASA Technical Reports Server (NTRS)

Martel, Hugo

1994-01-01

We study the effect of the cosmological constant Lambda on galaxy formation using a simple spherical top-hat overdensity model. We consider models with Omega(sub 0) = 0.2, lambda(sub 0) = 0, and Omega(sub 0) = 0.2, lambda(sub 0) = 0.8 (where Omega(sub 0) is the density parameter, and lambda(sub 0) identically equal Lambda/3 H(sub 0 exp 2) where H(sub 0) is the Hubble constant). We adjust the initial power spectrum amplitude so that both models reproduce the same large-scale structures. The galaxy formation era in the lambda(sub 0) = 0 model occurs early (z approximately 6) and is very short, whereas in the lambda(sub 0) = 0.8 model the galaxy formation era starts later (z approximately 4), and last much longer, possibly all the way to the present. Consequently, galaxies at low redshift (z less than 1) are significantly more evolved in the lambda(sub 0) = 0 model than in the lambda(sub 0) = 0.8 model. This result implies that previous attempts to determine Lambda using the number counts versus redshift test are probably unreliable.
Transgressive physiological and transcriptomic responses to light stress in allopolyploid Glycine dolichocarpa (Leguminosae).

PubMed

Coate, J E; Powell, A F; Owens, T G; Doyle, J J

2013-02-01

Allopolyploidy is often associated with increased photosynthetic capacity as well as enhanced stress tolerance. Excess light is a ubiquitous plant stress associated with photosynthetic light harvesting. We show that under chronic excess light, the capacity for non-photochemical quenching (NPQ(max)), a photoprotective mechanism, was higher in a recently formed natural allotetraploid (Glycine dolichocarpa, designated 'T2') than in its diploid progenitors (G. tomentella, 'D3'; and G. syndetika, 'D4'). This enhancement in NPQ(max) was due to an increase in energy-dependent quenching (qE) relative to D3, combined with an increase in zeaxanthin-dependent quenching (qZ) relative to D4. To explore the genetic basis for this phenotype, we profiled D3, D4 and T2 leaf transcriptomes and found that T2 overexpressed genes of the water-water cycle relative to both diploid progenitors, as well as genes involved in cyclic electron flow around photosystem I (CEF-PSI) and the xanthophyll cycle, relative to D4. Xanthophyll pigments have critical roles in NPQ, and the water-water cycle and CEF-PSI are non-photosynthetic electron transport pathways believed to facilitate NPQ formation. In the absence of CO(2), T2 also exhibited greater quantum yield of photosystem II than either diploid, indicating a greater capacity for non-photosynthetic electron transport. We postulate that, relative to its diploid progenitors, T2 is able to achieve higher NPQ(max) due to an increase in xanthophyll pigments coupled with enhanced electron flow through the water-water cycle and CEF-PSI.
[Plasma cell dyscrasias and renal damage].

PubMed

Pasquali, Sonia; Iannuzzella, Francesco; Somenzi, Danio; Mattei, Silvia; Bovino, Achiropita; Corradini, Mattia

2012-01-01

Kidney damage caused by immunoglobulin free light chains in the setting of plasma cell dyscrasias is common and may involve all renal compartments, from the glomerulus to the tubulointerstitium, in a wide variety of histomorphological and clinical patterns. The knowledge of how free light chains can promote kidney injury is growing: they can cause functional changes, be processed and deposited, mediate inflammation, apoptosis and fibrosis, and obstruct nephrons. Each clone of the free light chain is unique and its primary structure and post-translation modification can determine the type of renal disease. Measurement of serum free light chain concentrations and calculation of the serum kappa/lambda ratio, together with renal biopsy, represent essential diagnostic tools. An early and correct diagnosis of renal lesions due to plasma cell dyscrasias will allow early initiation of disease-specific treatment strategies. The treatment of free light chain nephropathies is evolving and knowledge of the pathways that promote renal damage should lead to further therapeutic developments.
Development of in-vitro models to elucidate mechanisms of intrinsic cellular and tissue fluorescence

NASA Astrophysics Data System (ADS)

Savage, Howard E.; Kolli, Venkateswara; Saha, Sanjoy; Zhang, Jian C.; Glasgold, Mark; Sacks, Peter G.; Alfano, Robert R.; Schantz, Stimson P.

1995-04-01

In vitro cell model systems have been used to study the mechanisms of intrinsic cellular and tissue fluorescence as a potential biomarker for cancer. Phenotypic characteristics of cancer that are different from normal tissue include changes in histoarchitecture, proliferation rates and differentiation. a nitrosmethlybenzylamine (NMBA)/rat esophageal carcinogenesis model (NMBA), a transforming growth factor beta (TGF- (beta) )/normal epithelial cell model, and a retinoic acid (RA)/multicellular tumor spheroid model (RAMTS) were used to assess fluorescence changes associated respectively with changes in histoarchitecture, proliferation rates and differentiation. A xenon based fluorescence spectrophotometer (Mediscience Corp.) was used to collect excitation and emission spectra. Two excitation scans ((lambda) Ex 200-360 nm, (lambda) Em 380 nm; (lambda) Ex 240-430 nm, (lambda) Em 450 nm) and two emission scans ((lambda) Ex 300 nm, (lambda) Em 320-580 nm; (lambda) Ex 340 nm, (lambda) Em 360-660 nm) were used to analyze the three model systems. Using the NMBA model. Differences were seen in the excitation scan ((lambda) Ex 200-360 nm, (lambda) Em 380 nm) and the emission scan ((lambda) Ex 340 nm, (lambda) Em 360-660 nm) when normal rat esophageal tissue was compared to hyperplastic and tumor tissue. In the (TGF-(beta) ) model, differences were seen in the excitation scan ((lambda) Ex 240-430 nm, (lambda) Em 450 nm) when comparing proliferation slowed (TGF-(beta) treated) epithelial cells to their untreated controls. In the RAMTS model, differences were seen with all four scans when RA treated multicellular tumor spheroids (nondifferentiating) were compared to untreated control cells (differentiating). The data indicate that fluorescence changes seen in these model systems may relate to changes in histoarchitecture, proliferation rates and differentiation. Their relationship to in vivo fluorescence changes seen in cancer patients remains to be elucidated.
Marginalizing Instrument Systematics in HST WFC3 Transit Light Curves

NASA Technical Reports Server (NTRS)

Wakeford, H. R.; Sing, D.K.; Deming, D.; Mandell, A.

2016-01-01

Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) infrared observations at 1.1-1.7 microns probe primarily the H2O absorption band at 1.4 microns, and have provided low-resolution transmission spectra for a wide range of exoplanets. We present the application of marginalization based on Gibson to analyze exoplanet transit light curves obtained from HST WFC3 to better determine important transit parameters such as "ramp" probability (R (sub p)) divided by "ramp" total (R (sub asterisk)), which are important for accurate detections of H2O. We approximate the evidence, often referred to as the marginal likelihood, for a grid of systematic models using the Akaike Information Criterion. We then calculate the evidence-based weight assigned to each systematic model and use the information from all tested models to calculate the final marginalized transit parameters for both the band-integrated and spectroscopic light curves to construct the transmission spectrum. We find that a majority of the highest weight models contain a correction for a linear trend in time as well as corrections related to HST orbital phase. We additionally test the dependence on the shift in spectral wavelength position over the course of the observations and find that spectroscopic wavelength shifts delta (sub lambda) times lambda) best describe the associated systematic in the spectroscopic light curves for most targets while fast scan rate observations of bright targets require an additional level of processing to produce a robust transmission spectrum. The use of marginalization allows for transparent interpretation and understanding of the instrument and the impact of each systematic evaluated statistically for each data set, expanding the ability to make true and comprehensive comparisons between exoplanet atmospheres.
Is colour modulation an independent factor in human visual photosensitivity?

PubMed

Parra, Jaime; Lopes da Silva, Fernando H; Stroink, Hans; Kalitzin, Stiliyan

2007-06-01

Considering that the role of colour in photosensitive epilepsy (PSE) remains unclear, we designed a study to determine the potential of different colours, colour combinations and white light to trigger photoparoxysmal responses (PPRs) under stringent controlled conditions. After assessing their photosensitivity to stroboscopic white light and black and white patterns, we studied 43 consecutive PSE patients (mean age 19 years, 34 women), using a specially designed colour stimulator. Stimuli included: pulse trains between 10 and 30 Hz of white light and of all primary colours, and also isoluminant alternating time-sequences of colours. Illuminance was kept constant at 100 lux. A progressive stepwise increase of the modulation-depth (MD) of the stimuli was used to determine PPRs threshold. Whereas all the 43 patients were found to be sensitive during the stroboscopic and pattern protocol, only 25 showed PPRs (Waltz's score >2) at least in one session when studied with the colour stimulator. Coloured stimuli elicited PPRs in all these patients, whereas white light did so only in 17 patients. Of the primary colours, red elicited more PPRs (54 in 22 patients) and at a lower MD (max Z-score 0.93 at 10 Hz). Of the alternating sequences, the red-blue was the most provocative stimulus, especially below 30 Hz (100% of patients, max Z-score: 1.65 at 15 Hz). Blue-green was the least provocative stimulus, since it elicited only seven PPRs in seven (28%) patients (max Z-score 0.44 at 10 Hz). Sensitivity to alternating colours was not correlated to sensitivity to individual colours. We conclude that colour sensitivity follows two different mechanisms: one, dependent on colour modulation, plays a role at lower frequencies (<30 Hz). Another, dependent on single-colour light intensity modulation correlates to white light sensitivity and is activated at higher frequencies. Our results suggest that the prescription of spectacles with coloured lenses, tailored to the patient, can be an effective preventative measure against visually induced seizures.
First measurement of the ratio of branching fractions B({lambda}{sub b}{sup 0}{yields}{lambda}{sub c}{sup +}{mu}{sup -}{nu}{sub {mu}})/B({lambda}{sub b}{sup 0}{yields}{lambda}{sub c}{sup +}{pi}{sup -})

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

Aaltonen, T.; Maki, T.; Mehtala, P.

2009-02-01

This article presents the first measurement of the ratio of branching fractions B({lambda}{sub b}{sup 0}{yields}{lambda}{sub c}{sup +}{mu}{sup -}{nu}{sub {mu}})/B({lambda}{sub b}{sup 0}{yields}{lambda}{sub c}{sup +}{pi}{sup -}). Measurements in two control samples using the same technique B(B{sup 0}{yields}D{sup +}{mu}{sup -}{nu}{sub {mu}})/B(B{sup 0}{yields}D{sup +}{pi}{sup -}) and B(B{sup 0}{yields}D*(2010){sup +}{mu}{sup -}{nu}{sub {mu}})/B(B{sup 0}{yields}D*(2010){sup +}{pi}{sup -}) are also reported. The analysis uses data from an integrated luminosity of approximately 172 pb{sup -1} of pp collisions at {radical}(s)=1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. The relative branching fractions are measured to be (B({lambda}{sub b}{sup 0}{yields}{lambda}{sub c}{sup +}{mu}{sup -}{nu}{sub {mu}})/B({lambda}{sub b}{sup 0}{yields}{lambda}{sub c}{supmore » +}{pi}{sup -}))=16.6{+-}3.0(stat){+-}1.0(syst)(+2.6/-3.4)(PDG){+-}0.3 (EBR), (B(B{sup 0}{yields}D{sup +}{mu}{sup -}{nu}{sub {mu}})/B(B{sup 0}{yields}D{sup +}{pi}{sup -}))9.9{+-}1.0(stat){+-}0.6(syst){+-}0.4(PDG){+-}0.5(EBR), and (B(B{sup 0}{yields}D*(2010){sup +}{mu}{sup -}{nu}{sub {mu}})/B(B{sup 0}{yields}D*(2010){sup +}{pi}{sup -}))=16.5{+-}2.3(stat){+-} 0.6(syst){+-}0.5(PDG){+-}0.8(EBR). The uncertainties are from statistics (stat), internal systematics (syst), world averages of measurements published by the Particle Data Group or subsidiary measurements in this analysis (PDG), and unmeasured branching fractions estimated from theory (EBR), respectively. This article also presents measurements of the branching fractions of four new {lambda}{sub b}{sup 0} semileptonic decays: {lambda}{sub b}{sup 0}{yields}{lambda}{sub c}(2595){sup +}{mu}{sup -}{nu}{sub {mu}}, {lambda}{sub b}{sup 0}{yields}{lambda}{sub c}(2625){sup +}{mu}{sup -}{nu}{sub {mu}}, {lambda}{sub b}{sup 0}{yields}{sigma}{sub c}(2455){sup 0}{pi}{sup +}{mu}{sup -}{nu}{sub {mu}}, and {lambda}{sub b}{sup 0}{yields}{sigma}{sub c}(2455){sup ++}{pi}{sup -}{mu}{sup -}{nu}{sub {mu}}, relative to the branching fraction of the {lambda}{sub b}{sup 0}{yields}{lambda}{sub c}{sup +}{mu}{sup -}{nu}{sub {mu}} decay. Finally, the transverse-momentum distribution of {lambda}{sub b}{sup 0} baryons produced in pp collisions is measured and found to be significantly different from that of B{sup 0} mesons, which results in a modification in the production cross-section ratio {sigma}{sub {lambda}{sub b}{sup 0}}/{sigma}{sub B{sup 0}} with respect to the CDF I measurement.« less
Maximal intended velocity training induces greater gains in bench press performance than deliberately slower half-velocity training.

PubMed

González-Badillo, Juan José; Rodríguez-Rosell, David; Sánchez-Medina, Luis; Gorostiaga, Esteban M; Pareja-Blanco, Fernando

2014-01-01

The purpose of this study was to compare the effect on strength gains of two isoinertial resistance training (RT) programmes that only differed in actual concentric velocity: maximal (MaxV) vs. half-maximal (HalfV) velocity. Twenty participants were assigned to a MaxV (n = 9) or HalfV (n = 11) group and trained 3 times per week during 6 weeks using the bench press (BP). Repetition velocity was controlled using a linear velocity transducer. A complementary study (n = 10) aimed to analyse whether the acute metabolic (blood lactate and ammonia) and mechanical response (velocity loss) was different between the MaxV and HalfV protocols used. Both groups improved strength performance from pre- to post-training, but MaxV resulted in significantly greater gains than HalfV in all variables analysed: one-repetition maximum (1RM) strength (18.2 vs. 9.7%), velocity developed against all (20.8 vs. 10.0%), light (11.5 vs. 4.5%) and heavy (36.2 vs. 17.3%) loads common to pre- and post-tests. Light and heavy loads were identified with those moved faster or slower than 0.80 m · s(-1) (∼ 60% 1RM in BP). Lactate tended to be significantly higher for MaxV vs. HalfV, with no differences observed for ammonia which was within resting values. Both groups obtained the greatest improvements at the training velocities (≤ 0.80 m · s(-1)). Movement velocity can be considered a fundamental component of RT intensity, since, for a given %1RM, the velocity at which loads are lifted largely determines the resulting training effect. BP strength gains can be maximised when repetitions are performed at maximal intended velocity.
Electromagnetically induced transparency and nonlinear pulse propagation in a combined tripod and Λ atom-light coupling scheme

NASA Astrophysics Data System (ADS)

Hamedi, H. R.; Ruseckas, J.; Juzeliūnas, G.

2017-09-01

We consider propagation of a probe pulse in an atomic medium characterized by a combined tripod and Lambda (Λ) atom-light coupling scheme. The scheme involves three atomic ground states coupled to two excited states by five light fields. It is demonstrated that dark states can be formed for such an atom-light coupling. This is essential for formation of the electromagnetically induced transparency (EIT) and slow light. In the limiting cases the scheme reduces to conventional Λ- or N-type atom-light couplings providing the EIT or absorption, respectively. Thus, the atomic system can experience a transition from the EIT to the absorption by changing the amplitudes or phases of control lasers. Subsequently the scheme is employed to analyze the nonlinear pulse propagation using the coupled Maxwell-Bloch equations. It is shown that a generation of stable slow light optical solitons is possible in such a five-level combined tripod and Λ atomic system.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Borland, M.; Hettel, R.; Leemann, S. C.

With the recent success in commissioning of MAX IV, the multi-bend achromat (MBA) lattice has begun to deliver on its promise to usher in a new generation of higher-brightness synchrotron light sources. In this paper, we begin by reviewing the challenges, recent success, and lessons learned of the MAX-IV project. Drawing on these lessons, we then describe the physics challenges in even more ambitious rings and how these can be met. In addition, we touch on engineering issues and choices that are tightly linked with the physics design.
SUMOylation of phytochrome-B negatively regulates light-induced signaling in Arabidopsis thaliana

PubMed Central

Sadanandom, Ari; Ádám, Éva; Orosa, Beatriz; Viczián, András; Klose, Cornelia; Zhang, Cunjin; Josse, Eve-Marie; Kozma-Bognár, László; Nagy, Ferenc

2015-01-01

The red/far red light absorbing photoreceptor phytochrome-B (phyB) cycles between the biologically inactive (Pr, λmax, 660 nm) and active (Pfr; λmax, 730 nm) forms and functions as a light quality and quantity controlled switch to regulate photomorphogenesis in Arabidopsis. At the molecular level, phyB interacts in a conformation-dependent fashion with a battery of downstream regulatory proteins, including PHYTOCHROME INTERACTING FACTOR transcription factors, and by modulating their activity/abundance, it alters expression patterns of genes underlying photomorphogenesis. Here we report that the small ubiquitin-like modifier (SUMO) is conjugated (SUMOylation) to the C terminus of phyB; the accumulation of SUMOylated phyB is enhanced by red light and displays a diurnal pattern in plants grown under light/dark cycles. Our data demonstrate that (i) transgenic plants expressing the mutant phyBLys996Arg-YFP photoreceptor are hypersensitive to red light, (ii) light-induced SUMOylation of the mutant phyB is drastically decreased compared with phyB-YFP, and (iii) SUMOylation of phyB inhibits binding of PHYTOCHROME INTERACTING FACTOR 5 to phyB Pfr. In addition, we show that OVERLY TOLERANT TO SALT 1 (OTS1) de-SUMOylates phyB in vitro, it interacts with phyB in vivo, and the ots1/ots2 mutant is hyposensitive to red light. Taken together, we conclude that SUMOylation of phyB negatively regulates light signaling and it is mediated, at least partly, by the action of OTS SUMO proteases. PMID:26283376
Preillumination of lettuce seedlings with red light enhances the resistance of photosynthetic apparatus to UV-A.

PubMed

Kreslavski, Vladimir D; Lyubimov, Valery Yu; Shirshikova, Galina N; Shmarev, Alexander N; Kosobryukhov, Anatoly A; Schmitt, Franz-Josef; Friedrich, Thomas; Allakhverdiev, Suleyman I

2013-05-05

Seedlings of 10-day-old lettuce (Lactuca sativa L., cultivar Berlin) were preilluminated by low intensity red light (λmax=660 nm, 10 min, 5 μmol quanta m(-2) s(-1)) and far-red light (λmax=730 nm, 10 min, 5 μmol quanta m(-2) s(-1)) to study the effect of pre-treatment on photosynthesis, photochemical activity of photosystem II (PSII), the contents of photosynthetic and UV-A-absorbing pigments (UAPs) and H2O2, as well as total and ascorbate peroxidase activities in cotyledonary leaves of seedlings exposed to UV-A. UV radiation reduced the photosynthetic rate (Pn), the activity of PSII, and the contents of Chl a and b, carotenoids and UAPs in the leaves, but increased the content of H2O2 and the total peroxidase activity. Preillumination with red light removed these effects of UV. In turn, the illumination with red light, then far-red light removed the effect of the red light. Illumination with red light alone increased the content of UAPs, as well as peroxidase activity. It is suggested that higher resistance of the lettuce photosynthetic apparatus to UV-A radiation is associated with involvement of the active form of phytochrome B, thereby increasing peroxidase activities as well as UAPs and saving preservation of photosynthetic pigment contents due to pre-illumination with red light. Copyright © 2013 Elsevier B.V. All rights reserved.
Prognostic Value of Serum Free Light Chain in Multiple Myeloma.

PubMed

El Naggar, Amel A; El-Naggar, Mostafa; Mokhamer, El-Hassan; Avad, Mona W

2015-01-01

The measurement of serum free light chain (sFLC) has been shown to be valuable in screening for the presence of plasma cell dyscrasia as well as for baseline prognosis in newly diagnosed patients. The aim of the present work was to study the prognostic value of sFLC in multiple myeloma in relation to other serum biomarkers, response to therapy and survival. Forty five newly diagnosed patients with MM were included in the study. Patients were divided into responders and non-responders groups according to response to therapy. sFLC and serum Amyloid A (SAA) were measured by immunonephelometry. The non-responders group showed a statistically significant higher kappa/lambda or lambda/kappa ratio and higher β2 microglobulin level, but lower albumin level at presentation, as compared to the responders group (P < 0.001). However, no statistically significant difference was detected between the two groups regarding SA A or calcium levels. Comparison between sFLC ratio obtained before and after therapy revealed significant decrease after treatment in the responders group (P = 0.05). Survival was significantly inferior in patients with an FLC ratio of ≥ 2.6 or ≤ 0.56 compared with those with an FLC ratio that was between 0.56 and 2.6 (P = 0.002).
Assessment of renal response with urinary exosomes in patients with AL amyloidosis: A proof of concept.

PubMed

Ramirez-Alvarado, Marina; Barnidge, David R; Murray, David L; Dispenzieri, Angela; Marin-Argany, Marta; Dick, Christopher J; Cooper, Shawna A; Nasr, Samih H; Ward, Christopher J; Dasari, Surendra; Jiménez-Zepeda, Víctor H; Leung, Nelson

2017-06-01

Immunoglobulin light chain (AL) amyloidosis is a fatal complication of B-cell proliferation secondary to deposition of amyloid fibrils in various organs. Urinary exosomes (UEX) are the smallest of the microvesicles excreted in the urine. Previously, we found UEX of patients with AL amyloidosis contained immunoglobulin light chain (LC) oligomers that patients with multiple myeloma did not have. To further explore the role of the LC oligomers, UEX was isolated from an AL amyloidosis patient with progressive renal disease despite achieving a complete response. LC oligomers were identified. Mass spectrometry (MS) of the UEX and serum identified two monoclonal lambda LCs. Proteomics of the trypsin digested amyloid fragments in the kidney by laser microdissection and MS analysis identified a λ6 LC. The cDNA from plasma cell clone was from the IGLV- 6-57 family and it matched the amino acid sequences of the amyloid peptides. The predicted mass of the peptide product of the cDNA matched the mass of one of the two LCs identified in the UEX and serum. UEX combined with MS were able to identify 2 monoclonal lambda LCs that current clinical methods could not. It also identified the amyloidogenic LC which holds potential for response assessment in the future. © 2017 Wiley Periodicals, Inc.

On the nature of the nova-like variable CD-42 deg 14462

NASA Technical Reports Server (NTRS)

Guinan, E. F.; Sion, E. M.

1981-01-01

Low dispersion long and short wavelength IUE spectra of the nova like system CD-42 deg 14462 were obtained on August 24 U.T. The short wave spectrum exhibits absorption features due to C III (lambda 1175), Lalpha 1216), NV (lambda1240), HeII (lambda 1640), SiIV (lambda1394), NIV (lambda1875) with CIV (lambda1550) as a P Cygni feature with blue shifted absorption suggesting the presence of material leaving the system. Possible interpretations of this object are discussed.
Anti p and anti Lambda production in Si + Au collisions at the AGS

NASA Technical Reports Server (NTRS)

Wu, Yue-Dong

1996-01-01

(anti (ital p)) and (anti (Lambda)) production in central Si + Au collisions has been measured by E589 at the BNL-AGS. Preliminary (ital m)(sub (perpendicular)) spectra are presented for (anti (ital p))'s and (anti (Lambda))'s. The (ital dn/dy) distribution for (anti (ital p))'s is also presented. Based on the (anti (ital p)) and (anti (Lambda)) measurements, (anti (Lambda))/(anti (ital p)) ratios are calculated in the rapidity range of 1.1-1.5.
Running Performance, VO2max, and Running Economy: The Widespread Issue of Endogenous Selection Bias.

PubMed

Borgen, Nicolai T

2018-05-01

Studies in sport and exercise medicine routinely use samples of highly trained individuals in order to understand what characterizes elite endurance performance, such as running economy and maximal oxygen uptake VO 2max . However, it is not well understood in the literature that using such samples most certainly leads to biased findings and accordingly potentially erroneous conclusions because of endogenous selection bias. In this paper, I review the current literature on running economy and VO 2max , and discuss the literature in light of endogenous selection bias. I demonstrate that the results in a large part of the literature may be misleading, and provide some practical suggestions as to how future studies may alleviate endogenous selection bias.
ASYMMETRIC ABSORPTION PROFILES OF Ly{alpha} AND Ly{beta} IN DAMPED Ly{alpha} SYSTEMS

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

Lee, Hee-Won, E-mail: hwlee@sejong.ac.kr

2013-08-01

Damped Ly{alpha} systems observed in the quasar spectra are characterized by a high neutral hydrogen column density, N{sub HI} > 2 x 10{sup 20} cm{sup -2}. The absorption wing profiles are often fitted using the Voigt function due to the fact that the scattering cross section near the resonant line center is approximately described by the Lorentzian function. Since a hydrogen atom has infinitely many p states that participate in the electric dipole interaction, the cross section starts to deviate from the Lorentzian in an asymmetric way in the line wing regions. We investigate this asymmetry in the absorption linemore » profiles around Ly{alpha} and Ly{beta} as a function of the neutral hydrogen column density N{sub HI}. In terms of {Delta}{lambda} {identical_to} {lambda} - {lambda}{sub {alpha}}, we expand the Kramers-Heisenberg formula around Ly{alpha} to find {sigma}({lambda}) {approx_equal} (0.5f{sub 12}){sup 2}{sigma}{sub T}({Delta}{lambda}/{lambda}{sub {alpha}}){sup -2}[1 + 3.792({Delta}{lambda}/{lambda}{sub {alpha}})], where f{sub 12} and {sigma}{sub T} are the oscillator strength of Ly{alpha} and the Thomson scattering cross section, respectively. In terms of {Delta}{lambda}{sub 2} {identical_to} {lambda} - {lambda}{sub {beta}} in the vicinity of Ly{beta}, the total scattering cross section, given as the sum of cross sections for Rayleigh and Raman scattering, is shown to be {sigma}({lambda}) {approx_equal} {sigma}{sub T}(0.5f{sub 13}){sup 2}(1 + R{sub 0})({Delta}{lambda}{sub 2}/{lambda}{sub {beta}}){sup -2}[1 - 24.68({Delta}{lambda}{sub 2}/{lambda}{sub {beta}})] with f{sub 13} and the factor R{sub 0} = 0.1342 being the oscillator strength for Ly{beta} and the ratio of the Raman cross section to Rayleigh cross section, respectively. A redward asymmetry develops around Ly{alpha}, whereas a blue asymmetry is obtained for Ly{beta}. The absorption center shifts are found to be almost proportional to the neutral hydrogen column density.« less
[Ecological and biological characteristics of Drosophila melanogaster features depending on the dose of electromagnetic radiation of various types].

PubMed

Babkina, V V; Chernova, G V; Allenova, E A; Endebera, O P; Naumkina, E N

2013-01-01

Biological effects of exposure to red light (lambda = 660 +/- 10 nm) on the viability and morphophysiological characteristics of Drosophila melanogaster have been studied. The ability of this physical agent to modify these features is shown. The degree of expression and impact of biological effects depend on the dose, functional and genetic status of the organism. The study of the life expectancy of the exposed to EHF and white light D. melanogaster has revealed that expression of the features depends on the radiation doses, genotype, sex, the nature of the position of wings and lighting conditions. It has been found that the dark mode (24 h-night) is more favorable than the artificial lighting. Individuals with the left wing at the top are more sensitive to the external factors.
Wind diagnostics and correlations with the near-infrared excess in Herbig Ae/Be stars

NASA Astrophysics Data System (ADS)

Corcoran, M.; Ray, T. P.

1998-03-01

Intermediate dispersion spectroscopic observations of 37 Herbig Ae/Be stars reveal that the equivalent widths of their [OI]lambda 6300 and Hα emission lines, are related to their near-infrared colours in the same fashion as the T-Tauri stars. Such a correlation strongly supports the idea that the winds from Herbig Ae/Be stars arise in the same manner as those from T-Tauri stars, i.e. through accretion driven mass-loss. We also find that the [OI]lambda 6300 line luminosity correlates better with excess infrared luminosity than with stellar luminosities, again supporting the idea that Herbig Ae/Be winds are accretion driven. If one includes the lower mass analogues of the Herbig Ae/Be stars with forbidden line emission, i.e. the classical T-Tauri stars, the correlation between mass-loss rate and infrared excess spans 5 orders of magnitude in luminosity and a range of masses from 0.5Msun to approximately 10Msun. Our observations therefore extend the findings of Cohen et al. (1989) and Cabrit et al. (1990) for low mass young stars and, taken in conjunction with other evidence (Corcoran & Ray 1997), strongly support the presence of circumstellar disks around intermediate mass stars with forbidden line emission. An implication of our findings is that the same outflow model must be applicable to these Herbig Ae/Be stars and the classical T Tauri stars. Based on observations made at the La Palma Observatory, the Caltech Submillimeter Observatory, and the European Southern Observatory/Max Planck Institute 2.2m Telescope.
A Study of Multi-Λ Hypernuclei Within Spherical Relativistic Mean-Field Approach

NASA Astrophysics Data System (ADS)

Rather, Asloob A.; Ikram, M.; Usmani, A. A.; Kumar, B.; Patra, S. K.

2017-12-01

This research article is a follow up of an earlier work by M. Ikram et al., reported in Int. J. Mod. Phys. E 25, 1650103 (2016) where we searched for Λ magic numbers in experimentally confirmed doubly magic nucleonic cores in light to heavy mass region (i.e., 16 O-208 P b) by injecting Λ's into them. In the present manuscript, working within the state of the art relativistic mean field theory with the inclusion of Λ N and ΛΛ interaction in addition to nucleon-meson NL 3∗ effective force, we extend the search of lambda magic numbers in multi- Λ hypernuclei using the predicted doubly magic nucleonic cores 292120, 304120, 360132, 370132, 336138, 396138 of the elusive superheavy mass regime. In analogy to well established signatures of magicity in conventional nuclear theory, the prediction of hypernuclear magicities is made on the basis of one-, two- Λ separation energy ( S Λ, S 2Λ) and two lambda shell gaps ( δ 2Λ) in multi- Λ hypernuclei. The calculations suggest that the Λ numbers 92, 106, 126, 138, 184, 198, 240, and 258 might be the Λ shell closures after introducing the Λ's in the elusive superheavy nucleonic cores. The appearance of new lambda shell closures apart from the nucleonic ones predicted by various relativistic and non-relativistic theoretical investigations can be attributed to the relatively weak strength of the spin-orbit coupling in hypernuclei compared to normal nuclei. Further, the predictions made in multi- Λ hypernuclei under study resembles closely the magic numbers in conventional nuclear theory suggested by various relativistic and non-relativistic theoretical models. Moreover, in support of the Λ shell closure, the investigation of Λ pairing energy and effective Λ pairing gap has been made. We noticed a very close agreement of the predicted Λ shell closures with the survey made on the pretext of S Λ, S 2Λ, and δ 2Λ except for the appearance of magic numbers corresponding to Λ = 156 which manifest in Λ effective pairing gap and pairing energy. Also, the lambda single-particle spectrum is analyzed to mark the energy shell gap for further strengthening the predictions made on the basis of separation energies and shell gaps. Lambda and nucleon spin-orbit interactions are analyzed to confirm the reduction in magnitude of Λ spin-orbit interaction compared to the nucleonic case, however the interaction profile is similar in both the cases. Lambda and nucleon density distributions have been investigated to reveal the impurity effect of Λ hyperons which make the depression of central density of the core of superheavy doubly magic nuclei. Lambda skin structure is also seen.
Light response of phytoplankton in the South Atlantic Ocean: Interpretation of observations and application to remote sensing

NASA Technical Reports Server (NTRS)

Hood, Raleigh R.

1995-01-01

A simplified, nonspectral derivation of a classical theory in plant physiology is presented and used to derive an absorption-based primary productivity algorithm. Field observations from a meridional transect (4 deg N to 42 deg S) in the Atlantic Ocean are then described and interpreted in this theoretical context. The observations include photosynthesis-irradiance curve parameters (alpha and P(sub max)), chlorophyll a and phaeopigment concentration, and estimated phytoplankton absorption coefficients at wavelength = 440 nm (a(sub ph)(440)). Observations near the top (50% I(sub 0)) and bottom (6% I(sub 0)) of the euphotic zone are contrasted. At both light levels, alpha, P(sub max), a(sub ph)(440), and pigment concentration varied similarly along the transect: values were highest at the equator and at the southern end of the transect and lowest in the central South Atlantic. It is concluded that this pattern was related to increased nutrient availability due to equatorial upwelling in the north, and increased wind mixing in the south. At the 50% light level, alpha increased relative to a(sub ph) at the southern end of the transect. This result appears to reflect a large-scale meridional (southward) increase in the average quantum efficiency of the photosynthetic units of the phytoplankton. A correlation analysis of the data reveals that at the 50% light level, variations in P(sub max) were more closely related to a(sub ph)(440) than chlorophyll concentration and that phytoplankton absorption explains 90% of the variability in P(sub max). In theory, this shows that the ratio of the average quantum efficiency of the photosynthetic units of the phytoplankton to the product of their average absorption cross section and turnover time is relatively constant. This result is used to simplify the absorption-based primary productivity algorithm derived previously. The feasibility of using this model to estimate production rate from satellite ocean color observations is discussed. It is concluded that an absorption-based algorithm should provide more accurate production rate estimates than one based upon chlorophyll (pigment) concentration.
Singlet oxygen triggers chloroplast rupture and cell death in the zeaxanthin epoxidase defective mutant aba1 of Arabidopsis thaliana under high light stress.

PubMed

Sánchez-Corrionero, Álvaro; Sánchez-Vicente, Inmaculada; González-Pérez, Sergio; Corrales, Ascensión; Krieger-Liszkay, Anja; Lorenzo, Óscar; Arellano, Juan B

2017-09-01

The two Arabidopsis thaliana mutants, aba1 and max4, were previously identified as sharing a number of co-regulated genes with both the flu mutant and Arabidopsis cell suspension cultures exposed to high light (HL). On this basis, we investigated whether aba1 and max4 were generating high amounts of singlet oxygen ( 1 O 2 ) and activating 1 O 2 -mediated cell death. Thylakoids of aba1 produced twice as much 1 O 2 as thylakoids of max4 and wild type (WT) plants when illuminated with strong red light. 1 O 2 was measured using the spin probe 2,2,6,6-tetramethyl-4-piperidone hydrochloride. 77-K chlorophyll fluorescence emission spectra of thylakoids revealed lower aggregation of the light harvesting complex II in aba1. This was rationalized as a loss of connectivity between photosystem II (PSII) units and as the main cause for the high yield of 1 O 2 generation in aba1. Up-regulation of the 1 O 2 responsive gene AAA-ATPase was only observed with statistical significant in aba1 under HL. Two early jasmonate (JA)-responsive genes, JAZ1 and JAZ5, encoding for two repressor proteins involved in the negative feedback regulation of JA signalling, were not up-regulated to the WT plant levels. Chloroplast aggregation followed by chloroplast rupture and eventual cell death was observed by confocal imaging of the fluorescence emission of leaf cells of transgenic aba1 plants expressing the chimeric fusion protein SSU-GFP. Cell death was not associated with direct 1 O 2 cytotoxicity in aba1, but rather with a delayed stress response. In contrast, max4 did not show evidence of 1 O 2 -mediated cell death. In conclusion, aba1 may serve as an alternative model to other 1 O 2 -overproducing mutants of Arabidopsis for investigating 1 O 2 -mediated cell death. Copyright © 2017 Elsevier GmbH. All rights reserved.
Measurement of sigma(Lambda(b)0) / sigma(anti-B 0) x B(Lambda0(b) ---> Lambda+(c) pi-) / B(anti-B0 ---> D+ pi-) in p anti-p collisions at S**(1/2) = 1.96-TeV

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

Abulencia, A.; Acosta, D.; Adelman, Jahred A.

2006-01-01

The authors present the first observation of the baryon decay {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +} {pi}{sup -} followed by {Lambda}{sub c}{sup +} {yields} pK{sup -} {pi}{sup +} in 106 pb{sup -1} p{bar p} collisions at {radical}s = 1.96 TeV in the CDF experiment. IN order to reduce systematic error, the measured rate for {Lambda}{sub b}{sup 0} decay is normalized to the kinematically similar meson decay {bar B}{sup 0} {yields} D{sup +}{pi}{sup -} followed by D{sup +} {yields} {pi}{sup +}K{sup -}{pi}{sup +}. They report the ratio of production cross sections ({sigma}) times the ratio of branching fractions ({Beta}) formore » the momentum region integrated above p{sub T} > 6 GeV/c and pseudorapidity range |{eta}| < 1.3: {sigma}(p{bar p} {yields} {Lambda}{sub b}{sup 0}X)/{sigma}(p{bar p} {yields} {bar B}{sup 0} X) x {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -})/{Beta}({bar B}{sup 0} {yields} D{sup +}{pi}{sup -}) = 0.82 {+-} 0.08(stat) {+-} 0.11(syst) {+-} 0.22 ({Beta}({Lambda}{sub c}{sup +} {yields} pK{sup -} {pi}{sup +})).« less
Inhibitory effect of tocotrienol on eukaryotic DNA polymerase {lambda} and angiogenesis

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

Mizushina, Yoshiyuki; Nakagawa, Kiyotaka; Shibata, Akira

2006-01-20

Tocotrienols, vitamin E compounds that have an unsaturated side chain with three double bonds, selectively inhibited the activity of mammalian DNA polymerase {lambda} (pol {lambda}) in vitro. These compounds did not influence the activities of replicative pols such as {alpha}, {delta}, and {epsilon}, or even the activity of pol {beta} which is thought to have a very similar three-dimensional structure to the pol {beta}-like region of pol {lambda}. Since {delta}-tocotrienol had the strongest inhibitory effect among the four ({alpha}- to {delta}-) tocotrienols, the isomer's structure might be an important factor in the inhibition of pol {lambda}. The inhibitory effect ofmore » {delta}-tocotrienol on both intact pol {lambda} (residues 1-575) and a truncated pol {lambda} lacking the N-terminal BRCA1 C-terminus (BRCT) domain (residues 133-575, del-1 pol {lambda}) was dose-dependent, with 50% inhibition observed at a concentration of 18.4 and 90.1 {mu}M, respectively. However, del-2 pol {lambda} (residues 245-575) containing the C-terminal pol {beta}-like region was unaffected. Tocotrienols also inhibited the proliferation of and formation of tubes by bovine aortic endothelial cells, with {delta}-tocotrienol having the greatest effect. These results indicated that tocotrienols targeted both pol {lambda} and angiogenesis as anti-cancer agents. The relationship between the inhibition of pol {lambda} and anti-angiogenesis by {delta}-tocotrienol was discussed.« less
The formation of low-ionization emission in the halo of NGC 891

NASA Technical Reports Server (NTRS)

Sokolowski, James; Bland-Hawthorn, Jonathan

1993-01-01

Imaging and Spectroscopic study first revealed the presence of a diffuse ionized medium (DIM), having unusual excitation, pervading the lower halo of the edge-on spiral galaxy NGC 891. Emission from this DIM is strongest northeast of the nucleus, at radii between 2 and 8 kpc (hereafter region 1). The (N2)(lambda)6583/H(alpha) and (S2)(lambda) (lambda)6716,6731/H(alpha) ratios increase dramatically with z in region 1, from 0.6 and 0.5 respectively at z is approximately equal to 500 pc to 1.1 and 1.0 at z is approximately equal to 1 kpc, while nondetections of (O1)(lambda)6300 and (O3)(lambda)5007 emission yield upper limits of (O1)(lambda)6300/H(alpha) less than or equal to 0.05 and (O3)(lambda)5007/H(alpha) less than or equal to 0.15 for z less than 1 kpc. Previous photoionization models, using the radiation field from disk O and B stars, have been successful in reproducing the elevated (N2)(lambda)6583/H(alpha) and (S2)(lambda)(lambda)6716.6731/H(alpha) ratios observed. However, these radiation bounded models also produce significant (O3)(lambda)5007 emission, in conflict with the observed upper limit. Here, we report the results of new, matter bounded models for the photoionization of the DIM in region 1 of NGC 891.
Measurement of the Lambda(0)(b) lifetime in the exclusive decay Lambda(0)(b) -> J/psi Lambda(0) in p(p)over-bar collisions at root s=1.96 TeV

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

Abazov V. M.; Abbott, B.; Acharya, B. S.

2012-06-07

We measure the {Lambda}{sub b}{sup 0} lifetime in the fully reconstructed decay {Lambda}{sub b}{sup 0} {yields} J/{psi}{Lambda}{sup 0} using 10.4 fb{sup -1} of p{bar p} collisions collected with the D0 detector at {radical}s = 1.96 TeV. The lifetime of the topologically similar decay channel B{sup 0} {yields} J/{psi}K{sub S}{sup 0} is also measured. We obtain {tau}({Lambda}{sub b}{sup 0}) = 1.303 {+-} 0.075(stat) {+-} 0.035(syst) ps and {tau}(B{sup 0}) = 1.508 {+-} 0.025(stat) {+-} 0.043(syst) ps. Using these measurements, we determine the lifetime ratio of {tau}({Lambda}{sub b}{sup 0})/{tau}(B{sup 0}) = 0.864 {+-} 0.052(stat) {+-} 0.033(syst).
UNiquant, a program for quantitative proteomics analysis using stable isotope labeling.

PubMed

Huang, Xin; Tolmachev, Aleksey V; Shen, Yulei; Liu, Miao; Huang, Lin; Zhang, Zhixin; Anderson, Gordon A; Smith, Richard D; Chan, Wing C; Hinrichs, Steven H; Fu, Kai; Ding, Shi-Jian

2011-03-04

Stable isotope labeling (SIL) methods coupled with nanoscale liquid chromatography and high resolution tandem mass spectrometry are increasingly useful for elucidation of the proteome-wide differences between multiple biological samples. Development of more effective programs for the sensitive identification of peptide pairs and accurate measurement of the relative peptide/protein abundance are essential for quantitative proteomic analysis. We developed and evaluated the performance of a new program, termed UNiquant, for analyzing quantitative proteomics data using stable isotope labeling. UNiquant was compared with two other programs, MaxQuant and Mascot Distiller, using SILAC-labeled complex proteome mixtures having either known or unknown heavy/light ratios. For the SILAC-labeled Jeko-1 cell proteome digests with known heavy/light ratios (H/L = 1:1, 1:5, and 1:10), UNiquant quantified a similar number of peptide pairs as MaxQuant for the H/L = 1:1 and 1:5 mixtures. In addition, UNiquant quantified significantly more peptides than MaxQuant and Mascot Distiller in the H/L = 1:10 mixtures. UNiquant accurately measured relative peptide/protein abundance without the need for postmeasurement normalization of peptide ratios, which is required by the other programs.
UNiquant, a Program for Quantitative Proteomics Analysis Using Stable Isotope Labeling

PubMed Central

Huang, Xin; Tolmachev, Aleksey V.; Shen, Yulei; Liu, Miao; Huang, Lin; Zhang, Zhixin; Anderson, Gordon A.; Smith, Richard D.; Chan, Wing C.; Hinrichs, Steven H.; Fu, Kai; Ding, Shi-Jian

2011-01-01

Stable isotope labeling (SIL) methods coupled with nanoscale liquid chromatography and high resolution tandem mass spectrometry are increasingly useful for elucidation of the proteome-wide differences between multiple biological samples. Development of more effective programs for the sensitive identification of peptide pairs and accurate measurement of the relative peptide/protein abundance are essential for quantitative proteomic analysis. We developed and evaluated the performance of a new program, termed UNiquant, for analyzing quantitative proteomics data using stable isotope labeling. UNiquant was compared with two other programs, MaxQuant and Mascot Distiller, using SILAC-labeled complex proteome mixtures having either known or unknown heavy/light ratios. For the SILAC-labeled Jeko-1 cell proteome digests with known heavy/light ratios (H/L = 1:1, 1:5, and 1:10), UNiquant quantified a similar number of peptide pairs as MaxQuant for the H/L = 1:1 and 1:5 mixtures. In addition, UNiquant quantified significantly more peptides than MaxQuant and Mascot Distiller in the H/L = 1:10 mixtures. UNiquant accurately measured relative peptide/protein abundance without the need for post-measurement normalization of peptide ratios, which is required by the other programs. PMID:21158445
Comparative visual ecology of cephalopods from different habitats.

PubMed

Chung, Wen-Sung; Marshall, N Justin

2016-09-14

Previous investigations of vision and visual pigment evolution in aquatic predators have focused on fish and crustaceans, generally ignoring the cephalopods. Since the first cephalopod opsin was sequenced in late 1980s, we now have data on over 50 cephalopod opsins, prompting this functional and phylogenetic examination. Much of this data does not specifically examine the visual pigment spectral absorbance position (λmax) relative to environment or lifestyle, and cephalopod opsin functional adaptation and visual ecology remain largely unknown. Here we introduce a new protocol for photoreceptor microspectrophotometry (MSP) that overcomes the difficulty of bleaching the bistable visual pigment and that reveals eight coastal coleoid cephalopods to be monochromatic with λmax varying from 484 to 505 nm. A combination of current MSP results, the λmax values previously characterized using cephalopod retinal extracts (467-500 nm) and the corresponding opsin phylogenetic tree were used for systematic comparisons with an end goal of examining the adaptations of coleoid visual pigments to different light environments. Spectral tuning shifts are described in response to different modes of life and light conditions. A new spectral tuning model suggests that nine amino acid substitution sites may determine the direction and the magnitude of spectral shifts. © 2016 The Authors.
A Randomized Study of Peginterferon Lambda-1a Compared to Peginterferon Alfa-2a in Combination with Ribavirin and Telaprevir in Patients with Genotype-1 Chronic Hepatitis C.

PubMed

Flisiak, Robert; Shiffman, Mitchell; Arenas, Juan; Cheinquer, Hugo; Nikitin, Igor; Dong, Yuping; Rana, Khurram; Srinivasan, Subasree

2016-01-01

A randomized, double-blind, multinational, phase 3 study was conducted comparing the efficacy and safety of peginterferon lambda-1a (Lambda)/ribavirin (RBV)/telaprevir (TVR) vs. peginterferon alfa-2a (Alfa)/RBV/TVR in patients with chronic hepatitis C virus (HCV) genotype-1 (GT-1) infection. Patients (treatment-naïve or relapsers on prior Alfa/RBV treatment) were randomly assigned in a 2:1 ratio to receive Lambda/RBV/TVR or Alfa/RBV/TVR. Total duration of treatment was either 24 or 48 weeks (response-guided treatment), with TVR administered for the first 12 weeks. The primary endpoint was the proportion of patients who achieved a sustained virologic response at post treatment week 12 (SVR12), which was tested for noninferiority of Lambda/RBV/TVR. A total of 838 patients were enrolled, and 617 were treated; 411 and 206 patients received Lambda/RBV/TVR and Alfa/RBV/TVR, respectively. The majority of patients were treatment-naïve, with HCV GT-1b and a high baseline viral load (≥800,000 IU/mL). Less than 10% of patients had cirrhosis (Lambda, 7.5%; Alfa, 6.8%). Lambda/RBV/TVR did not meet the criterion for noninferiority (lower bound of the treatment difference interval was -12.3%); the SVR12 in all patients (modified intent-to-treat) was 76.2% in the Lambda arm and 82.0% in the Alfa arm. Overall, the frequency of adverse events in each arm was comparable (Lambda, 91.7%; Alfa, 97.1%). As expected based on the safety profile of the 2 interferons, there were more hepatobiliary events observed in the Lambda arm and more hematologic events in the Alfa arm. In this comparison of Lambda/RBV/TVR and Alfa/RBV/TVR in patients who were treatment-naïve or had relapsed on prior Alfa/RBV treatment, Lambda failed to demonstrate noninferiority based on SVR12 results. Treatment with Lambda/RBV/TVR was associated with a higher incidence of relapse. More patients discontinued Lambda/RBV/TVR treatment during the first 4 weeks of study treatment, mainly due to hepatobiliary-related events, and more Lambda patients were lost to follow-up.
Human Anti-V3 HIV-1 Monoclonal Antibodies Encoded by the VH5-51/VL Lambda Genes Define a Conserved Antigenic Structure

PubMed Central

Gorny, Miroslaw K.; Sampson, Jared; Li, Huiguang; Jiang, Xunqing; Totrov, Maxim; Wang, Xiao-Hong; Williams, Constance; O'Neal, Timothy; Volsky, Barbara; Li, Liuzhe; Cardozo, Timothy; Nyambi, Phillipe; Zolla-Pazner, Susan; Kong, Xiang-Peng

2011-01-01

Preferential usage of immunoglobulin (Ig) genes that encode antibodies (Abs) against various pathogens is rarely observed and the nature of their dominance is unclear in the context of stochastic recombination of Ig genes. The hypothesis that restricted usage of Ig genes predetermines the antibody specificity was tested in this study of 18 human anti-V3 monoclonal Abs (mAbs) generated from unrelated individuals infected with various subtypes of HIV-1, all of which preferentially used pairing of the VH5-51 and VL lambda genes. Crystallographic analysis of five VH5-51/VL lambda-encoded Fabs complexed with various V3 peptides revealed a common three dimensional (3D) shape of the antigen-binding sites primarily determined by the four complementarity determining regions (CDR) for the heavy (H) and light (L) chains: specifically, the H1, H2, L1 and L2 domains. The CDR H3 domain did not contribute to the shape of the binding pocket, as it had different lengths, sequences and conformations for each mAb. The same shape of the binding site was further confirmed by the identical backbone conformation exhibited by V3 peptides in complex with Fabs which fully adapted to the binding pocket and the same key contact residues, mainly germline-encoded in the heavy and light chains of five Fabs. Finally, the VH5-51 anti-V3 mAbs recognized an epitope with an identical 3D structure which is mimicked by a single mimotope recognized by the majority of VH5-51-derived mAbs but not by other V3 mAbs. These data suggest that the identification of preferentially used Ig genes by neutralizing mAbs may define conserved epitopes in the diverse virus envelopes. This will be useful information for designing vaccine immunogen inducing cross-neutralizing Abs. PMID:22164215
Optical properties of CAD-CAM ceramic systems.

PubMed

Della Bona, Alvaro; Nogueira, Audrea D; Pecho, Oscar E

2014-09-01

To evaluate the direct transmittance (T%), translucency, opacity and opalescence of CAD-CAM ceramic systems and the correlation between the translucency parameter (TP) and the contrast ratio (CR). Specimens of shades A1, A2 and A3 (n=5) were fabricated from CAD-CAM ceramic blocks (IPS e.max(®) CAD HT and LT, IPS Empress(®) CAD HT and LT, Paradigm™ C, and VITABLOCS(®) Mark II) and polished to 1.0±0.01mm in thickness. A spectrophotometer (Lambda 20) was used to measure T% on the wavelength range of 400-780nm. Another spectrophotometer (VITA Easyshade(®) Advance) was used to measure the CIE L(*)a(*)b(*) coordinates and the reflectance value (Y) of samples on white and black backgrounds. TP, CR and the opalescence parameter (OP) were calculated. Data were statistically analysed using VAF (variance accounting for) coefficient with Cauchy-Schwarz inequality, one-way ANOVA, Tukey's test, Bonferroni correction and Pearson's correlation. T% of some ceramic systems is dependent on the wavelength. The spectral behaviour showed a slight and constant increase in T% up to approximately 550nm, then some ceramics changed the behaviour as the wavelength gets longer. TP and CR values ranged, respectively, from 16.79 to 21.69 and from 0.52 to 0.64 (r(2)=-0.97). OP values ranged from 3.01 to 7.64. The microstructure of CAD-CAM ceramic systems influenced the optical properties. TP and CR showed a strong correlation for all ceramic systems evaluated. Yet, all ceramics showed some degree of light transmittance. In addition to shade, this study showed that other optical properties influence on the natural appearance of dental ceramics. Copyright © 2014 Elsevier Ltd. All rights reserved.
Measurement of nitrophenols in rain and air by two-dimensional liquid chromatography-chemically active liquid core waveguide spectrometry.

PubMed

Ganranoo, Lucksagoon; Mishra, Santosh K; Azad, Abul K; Shigihara, Ado; Dasgupta, Purnendu K; Breitbach, Zachary S; Armstrong, Daniel W; Grudpan, Kate; Rappenglueck, Bernhard

2010-07-01

We report a novel system to analyze atmospheric nitrophenols (NPs). Rain or air sample extracts (1 mL) are preconcentrated on a narrow bore (2 mm) aliphatic anion exchanger. In the absence of strong retention of NPs exhibited by aromatic ion exchangers, retained NPs are eluted as a plug by injection of 100 microL of 0.1 M Na(2)SO(4) on to a short (2 x 50 mm) reverse phase C-18 column packed with 2.2 mum particles. The salt plug passes through the C-18 column unretained while the NPs are separated by an ammonium acetate buffered methanol-water eluent, compatible with mass spectrometry (MS). The eluted NPs are measured with a long path Teflon AF-based liquid core waveguide (0.15 x 1420 mm) illuminated by a 403 nm light emitting diode and detected by a monolithic photodiode-operational amplifier. The waveguide is rendered chemically active by suspending it over concentrated ammonia that permeates into the lumen. The NPs ionize to the yellow anion form (lambda(max) approximately 400 nm). The separation of 4-nitrophenol, 2,4-dinitrophenol, 2-methyl-4-nitrophenol, 3-methyl-4-nitrophenol, and 2-nitrophenol (these are the dominant NPs, typically in that order, in both rain and air of Houston and Arlington, TX, confirmed by tandem MS) takes just over 5 min with respective S/N = 3 limits of detection (LODs) of 60, 12, 30, 67, and 23 pg/mL compared to MS/MS LODs of 20, 49, 11, 20, and 210 pg/mL. Illustrative air and rain data are presented.

Cyclobutane pyrimidine dimers are photosensitised by carprofen plus UVA in human HaCaT cells.

PubMed

Robinson, K S; Traynor, N J; Moseley, H; Ferguson, J; Woods, J A

2010-06-01

Every year in the UK about 75,000 cases of non-melanoma skin cancer (NMSC) are registered, and about 9500 people are diagnosed with cutaneous melanoma (CM). The main risk factor for these cancers is exposure to sunlight. The effects of light on skin are wavelength dependent, with wavelengths in the UVB waveband (280-315 nm) being the most carcinogenic. UVB is directly absorbed by DNA, producing dimeric pyrimidine photoproducts including cyclobutane pyrimidine dimers (CPD) and pyrimidine (6-4) pyrimodone photoproducts (6-4PP). However UVA (315-400 nm) can also produce CPD, induce skin tumours in mice, and has been shown to be mutagenic in cell culture. Although the precise role of UVA in human skin cancer remains to be elucidated, it comprises the major portion of solar UV radiation, transmits through window glass and can be delivered in high doses from tanning lamps. Non-steroidal anti-inflammatory drugs (NSAIDs), in particular the 2-aryl propionic acid derivatives, are a well-documented group of photosensitising chemicals producing clinical phototoxic and photoallergic reactions. We have used carprofen, a model compound from this group to see if it could amplify the effects of UVA and contribute to the formation of CPD by UVA. Preliminary work has shown that carprofen combined with low doses of UVA (lambda(max): 365 nm; 5 J/cm(2)) can produce both strand breaks (SB) and CPD in human skin or blood cells. CPD were detected indirectly by both an immunofluorescence method and as T4 endonuclease V sensitive sites in the comet assay. These findings show that compounds other than fluoroquinolones and psoralen derivatives may contribute to CPD formation in skin cells in combination with UVA. Copyright 2010 Elsevier Ltd. All rights reserved.
Sustainability of the Catalytic Activity of a Silica-Titania Composite (STC) for Long-Term Indoor Air Quality Control

NASA Technical Reports Server (NTRS)

Coutts, Janelle L.; Levine, Lanfang H.; Richards, Jeffrey T.

2011-01-01

TiO2-assisted photocatalytic oxidation (PCO) is an emerging technology for indoor air quality control and is also being evaluated as an alternative trace contaminant control technology for crew habitats in space exploration. Though there exists a vast range of literature on the development of photocatalysts and associated reactor systems, including catalyst performance and performance-influencing factors, the critical question of whether photocatalysts can sustain their initial catalytic activity over an extended period of operation has not been adequately addressed. For a catalyst to effectively serve as an air quality control product, it must be rugged enough to withstand exposure to a multitude of low concentration volatile organic compounds (VOCs) over long periods of time with minimal loss of activity. The objective of this study was to determine the functional lifetime of a promising photocatalyst - the silica-titania composite (STC) from Sol Gel Solutions, LLC in a real-world scenario. A bench-scale STC-packed annular reactor under continuous irradiation by a UV-A fluorescent black-light blue lamp ((lambda)max = 365 nm) was exposed to laboratory air continuously at an apparent contact time of 0.27 sand challenged with a known concentration of ethanol periodically to assess any changes in catalytic activity. Laboratory air was also episodically spiked with halocarbons (e.g., octafluoropropane), organosulfur compounds (e.g., sulfur hexafluoride), and organosilicons (e.g., siloxanes) to simulate accidental releases or leaks of such VOCs. Total organic carbon (TOC) loading and contaminant profiles of the laboratory air were also monitored. Changes in STC photocatalytic performance were evaluated using the ethanol mineralization rate, mineralization efficiency, and oxidation intermediate (acetaldehyde) formation. Results provide insights to any potential catalyst poisoning by trace halocarbons and organosulfur compounds.
Optical super-resolution and periodical focusing effects by dielectric microspheres

NASA Astrophysics Data System (ADS)

Darafsheh, Arash

Optical microscopy is one of the oldest and most important imaging techniques; however, its far-field resolution is diffraction-limited. In this dissertation, we proposed and developed a novel method of optical microscopy with super-resolution by using high-index dielectric microspheres immersed in liquid and placed on the surface of the structures under study. We used barium titanate glass microspheres with diameters of D~2-220 mum and refractive indices n˜1.9-2.1 to discern minimal feature sizes ˜lambda/4 (down to ˜lambda/7) of various photonic and plasmonic nanostructures, where lambda is the illumination wavelength. We studied the magnification, field of view, and resolving power, in detail, as a function of sphere sizes. We studied optical coupling, transport, focusing, and polarization properties of linear arrays of dielectric spheres. We showed that in arrays of spheres with refractive index n=3, a special type of rays with transverse magnetic (TM) polarization incident on the spheres under the Brewster's angle form periodically focused modes with radial polarization and 2D period, where D is the diameter of the spheres. We showed that the formation of periodically focused modes in arrays of dielectric spheres gives a physical explanation for beam focusing and extraordinarily small attenuation of light in such chains. We showed that the light propagation in such arrays is strongly polarization-dependent, indicating that such arrays can be used as filters of beams with radial polarization. The effect of forming progressively smaller focused beams was experimentally observed in chains of sapphire spheres in agreement with the theory. We studied optical coupling,transport, focusing, and polarization properties of linear arrays of dielectric spheres. We showed that in arrays of spheres with refractive index n=a3, a special type of rays with transverse magnetic (TM) polarization incident on the spheres under the Brewster's angle form periodically focused modes with radial polarization and 2D period, where D is the diameter of the spheres. We showed that the formation of periodically focused modes in arrays of dielectric spheres gives a physical explanation for beam focusing and extraordinarily small attenuation of light in such chains. We showed that the light propagation in such arrays is strongly polarization-dependent, indicating that such arrays can be used as filters of beams with radial polarization. The effect of forming progressively smaller focused beams was experimentally observed in chains of sapphire spheres in agreement with the theory.
Pharmacokinetics of endogenous porphyrins induced by 5-aminolevulinic acid as observed by means of laser-induced fluorescence from several organs of tumor-bearing mice

NASA Astrophysics Data System (ADS)

Sroka, Ronald; Baumgartner, Reinhold; Beyer, Wolfgang; Gossner, Liebwin; Sassy, T.; Stocker, Susanne

1995-04-01

Photodynamic therapy (PDT) and photodynamic diagnosis (PDD) add support to efficient treatment modalities of superficial and early stage cancer. Recently 5-aminolevulinic acid (5-ALA), a precursor of hemoglobin in the hem biosynthetic pathway, was used to stimulate endogenous porphyrin production. The time dependency of 5-ALA induced porphyrin fluorescence has been investigated on several normal tissues as well as on a tumor in an in-vivo tumor model (human gastrointestinal adenocarcinoma Grade II, UICC IIa). 5-ALA has been administered intravenously at a concentration of 50 mg/(kg bw). With respect to a certain time schedule the animals were sacrificed and 12 different organs as well as the tumor were removed. Using laser-induced fluorescence techniques the emission spectra in the range of (lambda) equals (550-750) nm were detected from the tissues after excitation with light of the wavelength (lambda) equals (411 +/- 4) nm. For quantitative evaluation the integral fluorescence intensity at (lambda) equals (635 +/- 2) nm of the porphyrin specific spectra has been determined. All tissues showed porphyrin fluorescence, while brightest fluorescence has been detected from the tumor. With respect to the other tissues the relative tumor selectivity showed a maximum ratio at 406 h post injection. The kinetics of the porphyrin fluorescence intensity of the organs follow different time dependencies. Simple mathematical pharmacokinetic models are developed and discussed.
Effect of temperature on photosynthesis-light response and growth of four phytoplankton species isolated from a tidal freshwater river

USGS Publications Warehouse

Coles, J.F.; Jones, R.C.

2000-01-01

Three cyanobacteria (Microcystis aeruginosa Kutz. emend. Elenkin, Merismopedia tenuissima Lemmermann, and Oscillatoria sp.) and one diatom (Aulacoseira granulata var. angustissima O. Mull. emend. Simonsen) were isolated from the tidal freshwater Potomac River and maintained at 23??C and 40 ??mol photons??m-2??s-1 on a 16:8 L:D cycle in unialgal culture. Photosynthetic parameters were determined in nutrient-replete cultures growing exponentially at 15, 20, 25, and 30??C by incubation with 14C at six light levels. P(B)(max) was strongly correlated with temperature over the entire range for the cyanobacteria and from 15 to 25??C for Aulacoseira, with Q10 ranging from 1.79 to 2.67. The ?? values demonstrated a less consistent temperature pattern. Photosynthetic parameters indicated an advantage for cyanobacteria at warmer temperatures and in light-limited water columns. P(B)(max) and I(k) values were generally lower than comparable literature and field values, whereas ?? was generally higher, consistent with a somewhat shade acclimated status of our cultures. Specific growth rate (??), as measured by chlorophyll change, was strongly influenced by temperature in all species. Oscillatoria had the highest ?? at all temperatures, joined at lower temperatures by Aulacoseira and at higher temperatures by Microcystis. Values of ?? for Aulacaseira were near the low end of the literature range for diatoms consistent with the light-limited status of the cultures. The cyanobacteria exhibited growth rates similar to those reported in other studies. Q10 for growth ranged from 1.71 for Aulacoseira to 4.16 for Microcystis. Growth rate was highly correlated with P(B)(max) for each species and the regression slope coefficients were very similar for three of the species.
Apparatus and method for closed-loop control of reactor power in minimum time

DOEpatents

Bernard, Jr., John A.

1988-11-01

Closed-loop control law for altering the power level of nuclear reactors in a safe manner and without overshoot and in minimum time. Apparatus is provided for moving a fast-acting control element such as a control rod or a control drum for altering the nuclear reactor power level. A computer computes at short time intervals either the function: .rho.=(.beta.-.rho.).omega.-.lambda..sub.e '.rho.-.SIGMA..beta..sub.i (.lambda..sub.i -.lambda..sub.e ')+l* .omega.+l* [.omega..sup.2 +.lambda..sub.e '.omega.] or the function: .rho.=(.beta.-.rho.).omega.-.lambda..sub.e .rho.-(.lambda..sub.e /.lambda..sub.e)(.beta.-.rho.)+l* .omega.+l* [.omega..sup.2 +.lambda..sub.e .omega.-(.lambda..sub.e /.lambda..sub.e).omega.] These functions each specify the rate of change of reactivity that is necessary to achieve a specified rate of change of reactor power. The direction and speed of motion of the control element is altered so as to provide the rate of reactivity change calculated using either or both of these functions thereby resulting in the attainment of a new power level without overshoot and in minimum time. These functions are computed at intervals of approximately 0.01-1.0 seconds depending on the specific application.
Plasma Cell Cheilitis: A Clinicopathological and Immunohistochemical Study of 13 Cases

PubMed Central

Lee, Jin Yong; Kim, Kwang Ho; Hahm, Ji Eun; Ha, Jae Won; Kwon, Won Joo; Kim, Chul Woo

2017-01-01

Background Plasma cell cheilitis is an unusual benign plasma cell proliferative disease of an unknown etiology that typically presents on the lip. Objective The aim of this study was to investigate the clinicopathological characteristics of 13 cases of plasma cell cheilitis. Methods The present study investigated the clinical manifestations, treatment modalities, and outcome of 13 patients diagnosed with plasma cell cheilitis from 2011 to 2016 at Kangdong Sacred Heart Hospital and Hallym University Sacred Heart Hospital. Biopsy specimens of the all cases were evaluated using conventional hematoxylin and eosin staining with kappa and lambda immunoglobulin light chain immunohistochemistry. Results The age of the patients ranged from 39 to 86 years (mean, 64.7 years), with male predominance. Histopathologically, 61.5% and 38.5% of patients showed band-like and pan dermal plasmacytic infiltrates, respectively. Eosinophilic infiltration was noted in 69.2% of patients. All cases showed both kappa and lambda immunoglobulin light chain reactivities, and kappa predominance was confirmed in 9 patients (69.2%). A majority of the patients was treated with local therapy, such as intralesional steroid injection with topical tacrolimus. Among the 13 patients, plasma cell cheilitis completely resolved, partially resolved, and recurred in 3 (23.1%), 5 (38.5%), and 5 patients (38.5%), respectively. Conclusion Plasma cell cheilitis presented as erosive edematous circumscribed patches or plaques affecting mainly the lower lip of elderly male patients. The majority of histopathology cases showed characteristic plasma cell aggregation on the upper dermis that was immunopositive for immunoglobulin light chain, with kappa predominance. PMID:28966508
In situ temperature relationships of biochemical and stomatal controls of photosynthesis in four lowland tropical tree species.

PubMed

Slot, Martijn; Winter, Klaus

2017-12-01

Net photosynthetic carbon uptake of Panamanian lowland tropical forest species is typically optimal at 30-32 °C. The processes responsible for the decrease in photosynthesis at higher temperatures are not fully understood for tropical trees. We determined temperature responses of maximum rates of RuBP-carboxylation (V CMax ) and RuBP-regeneration (J Max ), stomatal conductance (G s ), and respiration in the light (R Light ) in situ for 4 lowland tropical tree species in Panama. G s had the lowest temperature optimum (T Opt ), similar to that of net photosynthesis, and photosynthesis became increasingly limited by stomatal conductance as temperature increased. J Max peaked at 34-37 °C and V CMax ~2 °C above that, except in the late-successional species Calophyllum longifolium, in which both peaked at ~33 °C. R Light significantly increased with increasing temperature, but simulations with a photosynthesis model indicated that this had only a small effect on net photosynthesis. We found no evidence for Rubisco-activase limitation of photosynthesis. T Opt of V CMax and J Max fell within the observed in situ leaf temperature range, but our study nonetheless suggests that net photosynthesis of tropical trees is more strongly influenced by the indirect effects of high temperature-for example, through elevated vapour pressure deficit and resulting decreases in stomatal conductance-than by direct temperature effects on photosynthetic biochemistry and respiration. © 2017 John Wiley & Sons Ltd.
Behavioral and physiological photoresponses to light intensity by intertidal microphytobenthos

NASA Astrophysics Data System (ADS)

Du, Guoying; Yan, Hongmei; Liu, Chunrong; Mao, Yunxiang

2018-03-01

Behavioral and physiological responses to light are the two major mechanisms by which natural microphytobenthic assemblages adapt to the intertidal environment and protect themselves from light stress. The present study investigated these photoresponses with different light intensities over 8 h of illumination, and used a specific inhibitor (Latrunculin A, Lat A) for migration to compare migratory and non-migratory microphytobenthos (MPB). Photosynthetic activity was detected using rapid light curves and induction curves by chlorophyll fluorescence. It showed distinct variation in migratory responses to different light intensities; high light induced downward migration to avoid photoinhibition, and low and medium light (50-250 μmol/(m2·s)) promoted upward migration followed by downward migration after certain period of light exposure. No significant difference in non-photochemical quenching (NPQ) or PSII maximal quantum yield ( F v/ F m) was detected between low and medium light irradiance, possibly indicating that only high light influences the photosynthetic capability of MPB. Decreased photosynthetic activity, indicated by three parameters, the maximum relative electron transport rate (rETR max), minimum saturating irradiance ( E k) and light utilization coefficient ( α), was observed in MPB after exposure to prolonged illumination under low and medium light. Lat A effectively inhibited the migration of MPB in all light treatments and induced lower F v/ F m under high light (500 and 100 μmol/(m2·s)) and prolonged illumination at 250 μmol/(m2·s), but did not significantly influence F v/ F m under low light (0-100 μmol/(m2·s)) or NPQ. The increase of NPQ in Lat A treatments with time implied that the MPB assemblages can recover their physiological photoprotection capacity to adapt to light stress. Non-migratory MPB exhibited lower light use efficiency (lower α) and lower maximum photosynthetic capacity (lower rETR max) than migratory MPB under light intensities above 250 μmol/(m2·s) after 4.0 h illumination.
On Spectral Invariance of Single Scattering Albedo for Weakly Absorbing Wavelengths

NASA Technical Reports Server (NTRS)

Marshak, Alexander; Knyazikhin, Yuri; Chiu, J. Christine; Wiscombe, Warren J.

2011-01-01

This note shows that for water droplets at weakly absorbing wavelengths, the ratio omega(sub O lambda(r))/omega(sub O lambda(r(sub O)) of two single scattering albedo spectra, omega(sub O lambda(r) and omega(sub O lambda(r (sub O)), is a linear function of omega(sub O lambda(r). The slope and intercept of the linear function are wavelength independent and sum to unity. This relationship allows for a representation of any single scattering albedo omega(sub O lambda(r) via one known spectrum omega(sub O lambda(r(sub O)). The note provides a simple physical explanation of the discovered relationship. In addition to water droplets, similar linear relationships were found for the single scattering albedo of non-spherical ice crystals.
Pegylated interferons Lambda-1a and alfa-2a display different gene induction and cytokine and chemokine release profiles in whole blood, human hepatocytes and peripheral blood mononuclear cells.

PubMed

Freeman, J; Baglino, S; Friborg, J; Kraft, Z; Gray, T; Hill, M; McPhee, F; Hillson, J; Lopez-Talavera, J C; Wind-Rotolo, M

2014-06-01

Pegylated interferon-lambda-1a (Lambda), a type III interferon (IFN) in clinical development for the treatment of chronic HCV infection, has shown comparable efficacy and an improved safety profile to a regimen based on pegylated IFN alfa-2a (alfa). To establish a mechanistic context for this improved profile, we investigated the ex vivo effects of Lambda and alfa on cytokine and chemokine release, and on expression of IFN-stimulated genes (ISGs) in primary human hepatocytes and peripheral blood mononuclear cells (PBMCs) from healthy subjects. Our findings were further compared with changes observed in blood analysed from HCV-infected patients treated with Lambda or alfa in clinical studies. mRNA transcript and protein expression of the IFN-λ-limiting receptor subunit was lower compared with IFN-α receptor subunits in all cell types. Upon stimulation, alfa and Lambda induced ISG expression in hepatocytes and PBMCs, although in PBMCs Lambda-induced ISG expression was modest. Furthermore, alfa and Lambda induced release of cytokines and chemokines from hepatocytes and PBMCs, although differences in their kinetics of induction were observed. In HCV-infected patients, alfa treatment induced ISG expression in whole blood after single and repeat dosing. Lambda treatment induced modest ISG expression after single dosing and showed no induction after repeat dosing. Alfa and Lambda treatment increased IP-10, iTAC, IL-6, MCP-1 and MIP-1β levels in serum, with alfa inducing higher levels of all mediators compared with Lambda. Overall, ex vivo and in vivo induction profiles reported in this analysis strongly correlate with clinical observations of fewer related adverse events for Lambda vs those typically associated with alfa. © 2014 John Wiley & Sons Ltd.
Environmental chemistry, ecotoxicity, and fate of lambda-cyhalothrin.

PubMed

He, Li-Ming; Troiano, John; Wang, Albert; Goh, Kean

2008-01-01

Lambda-cyhalothrin is a pyrethroid insecticide used for controlling pest insects in agriculture, public health, and in construction and households. Lambda-cyhalothrin is characterized by low vapor pressure and a low Henry's law constant but by a high octanol-water partition coefficient (K(ow)) and high water-solid-organic carbon partition coefficient (K(oc)) values. Lambda-cyhalothrin is quite stable in water at pH < 8, whereas it hydrolyzes to form HCN and aldehyde under alkaline conditions. Although lambda-cyhalothrin is relatively photostable under natural irradiation, with a half-life > 3 wk, its photolysis process is fast under UV irradiation, with a half-life < 10 min. The fate of lambda-cyhalothrin in aquatic ecosystems depends on the nature of system components such as suspended solids (mineral and organic particulates) and aquatic organisms (algae, macrophytes, or aquatic animals). Lambda-cyhalothrin residues dissolved in water decrease rapidly if suspended solids and/or aquatic organisms are present because lambda-cyhalothrin molecules are strongly adsorbed by particulates and plants. Adsorbed lambda-cyhalothrin molecules show decreased degradation rates because they are less accessible to breakdown than free molecules in the water column. On the other hand, lambda-cyhalothrin adsorbed to suspended solids or bottom sediments may provide a mechanism to mitigate its acute toxicity to aquatic organisms by reducing their short-term bioavailability in the water column. The widespread use of lambda-cyhalothrin has resulted in residues in sediment, which have been found to be toxic to aquatic organisms including fish and amphipods. Mitigation measures have been used to reduce the adverse impact of lambda-cyhalothrin contributed from agricultural or urban runoff. Mitigation may be achieved by reducing the quantity of runoff and suspended solid content in runoff through wetlands, detention ponds, or vegetated ditches.
Non-LTE radiative transfer with lambda-acceleration - Convergence properties using exact full and diagonal lambda-operators

NASA Technical Reports Server (NTRS)

Macfarlane, J. J.

1992-01-01

We investigate the convergence properties of Lambda-acceleration methods for non-LTE radiative transfer problems in planar and spherical geometry. Matrix elements of the 'exact' A-operator are used to accelerate convergence to a solution in which both the radiative transfer and atomic rate equations are simultaneously satisfied. Convergence properties of two-level and multilevel atomic systems are investigated for methods using: (1) the complete Lambda-operator, and (2) the diagonal of the Lambda-operator. We find that the convergence properties for the method utilizing the complete Lambda-operator are significantly better than those of the diagonal Lambda-operator method, often reducing the number of iterations needed for convergence by a factor of between two and seven. However, the overall computational time required for large scale calculations - that is, those with many atomic levels and spatial zones - is typically a factor of a few larger for the complete Lambda-operator method, suggesting that the approach should be best applied to problems in which convergence is especially difficult.
Mass and K{lambda} Coupling of the N*(1535)

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

Liu, B.C.; Graduate School of the Chinese Academy of Sciences, Beijing 100049; Zou, B.S.

2006-02-03

Using a resonance isobar model and an effective Lagrangian approach, from recent BES results on J/{psi}{yields}pp{eta} and {psi}{yields}pK{sup +}{lambda}, we deduce the ratio between effective coupling constants of N*(1535) to K{lambda} and p{eta} to be R{identical_to}g{sub N*(1535)K{lambda}}/g{sub N*(1535)p{eta}}=1.3{+-}0.3. With the previous known value of g{sub N*(1535)p{eta}}, the obtained new value of g{sub N*(1535)K{lambda}} is shown to reproduce recent pp{yields}pK{sup +}{lambda} near-threshold cross section data as well. Taking into account this large N*K{lambda} coupling in the coupled channel Breit-Wigner formula for the N*(1535), its Breit-Wigner mass is found to be around 1400 MeV, much smaller than the previous value of aboutmore » 1535 MeV obtained without including its coupling to K{lambda}. The implication on the nature of N*(1535) is discussed.« less
[Effects of simulating acid rain on photosynthesis and chlorophyll fluorescence parameters of Quercus glauca Quercus glauca].

PubMed

Wang, Sai; Yi, Li-Ta; Yu, Shu-Quan; Zhang, Chao; Shi, Jing-Jing

2014-08-01

At three levels of simulated acid rainfall intensities with pH values of 2.5 (severe), 40 (medium) and 5.6 (light) respectively, the responses of chlorophyll fluorescence and photosynthetic parameters of Quercus glauca seedlings were studied in three acid rainfall treatments, i. e. only the aboveground of seedlings exposed to acid rain (T1), both of the seedlings and soil exposed to acid rain (T2), only the soil exposed to acid rain (T3) compared with blank control (CK). Under the severe acid rainfall, T1 significantly inhibited chlorophyll synthesis, and thus reduced the primary photochemical efficiency of PS II ( F(v)/F(m)), potential activity of PS II (F(v)/F(o)) , apparent quantum (Y), net photosynthetic rate (P(n)), and transpiration rate (T(r)), but increased the light compensation point (LCP) and dark respiration rate (R(d)) of Q. glauca seedlings. T2 inhibited, but T3 played a little enhancement on the aforementioned parameters of Q. glauca seedlings. Under the conditions of medium and light acid rainfall intensities, the above parameters in the three treatments were higher than that of CK, except with lower R(d). The chlorophyll fluorescence and photosynthetic parameters showed a similar tendency in the three treatments, i. e. T2>T3 >T1. It indicated that T1 had the strongest inhibition on seedlings in condition of the severe acid rainfall, while T2 had the most dramatic facilitating effect on seedlings under the medium and light acid rainfall. Intensity of acid rainfall had significant influences on SPAD, F(v)/F(m), F(v)/F(o), Y, P(n), T(r), and maximum photosynthetic rate (A(max)), whereas treatments of acid rainfall affected SPAD, F(v)/F(m), Y, P(n), T(r), A(max) and light saturation point (LSP). The interaction of acid rainfall intensities and treatments played significant effects on SPAD, F(v)/F(m), Y, P(n) and A(max).
Peginterferon lambda for the treatment of HBeAg-positive chronic hepatitis B: A randomized phase 2b study (LIRA-B).

PubMed

Chan, Henry L Y; Ahn, Sang Hoon; Chang, Ting-Tsung; Peng, Cheng-Yuan; Wong, David; Coffin, Carla S; Lim, Seng Gee; Chen, Pei-Jer; Janssen, Harry L A; Marcellin, Patrick; Serfaty, Lawrence; Zeuzem, Stefan; Cohen, David; Critelli, Linda; Xu, Dong; Wind-Rotolo, Megan; Cooney, Elizabeth

2016-05-01

Peginterferon lambda-1a (lambda) is a Type-III interferon, which, like alfa interferons, has antiviral activity in vitro against hepatitis B virus (HBV) and hepatitis C virus (HCV); however, lambda has a more limited extra-hepatic receptor distribution. This phase 2b study (LIRA-B) evaluated lambda in patients with chronic HBV infection. Adult HBeAg+ interferon-naive patients were randomized (1:1) to weekly lambda (180 μg) or peginterferon alfa-2a (alfa) for 48 weeks. The primary efficacy endpoint was HBeAg seroconversion at week 24 post-treatment; lambda non-inferiority was demonstrated if the 80% confidence interval (80% CI) lower bound was >-15%. Baseline characteristics were balanced across groups (lambda N=80; alfa N=83). Early on-treatment declines in HBV-DNA and qHBsAg through week 24 were greater with lambda. HBeAg seroconversion rates were comparable for lambda and alfa at week 48 (17.5% vs. 16.9%, respectively); however lambda non-inferiority was not met at week 24 post-treatment (13.8% vs. 30.1%, respectively; lambda vs. alfa 80% CI lower bound -24%). Results for other key secondary endpoints (virologic, serologic, biochemical) and post hoc combined endpoints (HBV-DNA <2000 IU/ml plus HBeAg seroconversion or ALT normalization) mostly favored alfa. Overall adverse events (AE), serious AE, and AE-discontinuation rates were comparable between arms but AE-spectra differed (more cytopenias, flu-like, and musculoskeletal symptoms observed with alfa, more ALT flares and bilirubin elevations seen with lambda). Most on-treatment flares occurred early (weeks 4-12), associated with HBV-DNA decline; all post-treatment flares were preceded by HBV-DNA rise. On-treatment, lambda showed greater early effects on HBV-DNA and qHBsAg, and comparable serologic/virologic responses at end-of-treatment. However, post-treatment, alfa-associated HBeAg seroconversion rates were higher, and key secondary results mostly favored alfa. ClinicalTrials.gov number: NCT01204762. Copyright © 2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
First Observation of Charmed Resonances in the $$\\Lambda^0_b \\to \\Lambda^+_c \\pi^- \\pi^+ \\pi^-$$ Inclusive Decay and Measurement of Their Relative Branching Ratios at CDF

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

Barria, Patrizia

2012-01-01

We present the observation of themore » $$\\Lambda^0_b$$ decay into a $$\\Lambda^+_c \\pi^- \\pi^+ \\pi^-$$ final state, in $$p\\bar{p}$$ collisions at $$\\sqrt{s}$$ = 1:96 TeV. The data analyzed were collected by the CDF II detector at the Fermilab Tevatron collider, and correspond to 2:4 $$fb^{-1}$$ of integrated luminosity. We fit the invariant mass distribution of the reconstructed candidates to extract a signal yield of 848 $$\\pm$$ 93 $$\\Lambda^0_b$$ into $$\\Lambda^+_c \\pi^- \\pi^+ \\pi^-$$....« less
Further observations of the lambda 10830 He line in stars and their significance as a measure of stellar activity

NASA Technical Reports Server (NTRS)

Zirin, H.

1975-01-01

Measurements of the lambda 1030 He line in 198 stars are given along with data on other features in that spectral range. Nearly 80% of all G and K stars show some lambda 10830; of these, half are variable and 1/4 show emission. It was confirmed that lambda 10830 is not found in M stars, is weak in F stars, and is particularly strong in close binaries. The line is found in emission in extremely late M and S stars, along with P gamma, but P gamma is not in emission in G and K stars with lambda 10830 emissions. Variable He emission and Ti I emission are found in the RV Tauri variables R Scuti and U Mon. In R Aqr the Fe XIII coronal line lambda 10747 and a line at lambda 11012 which may be singlet He or La II are found, as well as lambda 10830 and P gamma. The nature of coronas or hot chromospheres in the various stars is discussed. It was concluded that the lambda 10830 intensity must be more or less proportional to the energy deposited in the chromosphere corona by non-thermal processes.
A photon spectrometric dose-rate constant determination for the Advantage Pd-103 brachytherapy source

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

Chen, Zhe Jay; Bongiorni, Paul; Nath, Ravinder

Purpose: Although several dosimetric characterizations using Monte Carlo simulation and thermoluminescent dosimetry (TLD) have been reported for the new Advantage Pd-103 source (IsoAid, LLC, Port Richey, FL), no AAPM consensus value has been established for the dosimetric parameters of the source. The aim of this work was to perform an additional dose-rate constant ({Lambda}) determination using a recently established photon spectrometry technique (PST) that is independent of the published TLD and Monte Carlo techniques. Methods: Three Model IAPD-103A Advantage Pd-103 sources were used in this study. The relative photon energy spectrum emitted by each source along the transverse axis wasmore » measured using a high-resolution germanium spectrometer designed for low-energy photons. For each source, the dose-rate constant was determined from its emitted energy spectrum. The PST-determined dose-rate constant ({sub PST}{Lambda}) was then compared to those determined by TLD ({sub TLD}{Lambda}) and Monte Carlo ({sub MC}{Lambda}) techniques. A likely consensus {Lambda} value was estimated as the arithmetic mean of the average {Lambda} values determined by each of three different techniques. Results: The average {sub PST}{Lambda} value for the three Advantage sources was found to be (0.676{+-}0.026) cGyh{sup -1} U{sup -1}. Intersource variation in {sub PST}{Lambda} was less than 0.01%. The {sub PST}{Lambda} was within 2% of the reported {sub MC}{Lambda} values determined by PTRAN, EGSnrc, and MCNP5 codes. It was 3.4% lower than the reported {sub TLD}{Lambda}. A likely consensus {Lambda} value was estimated to be (0.688{+-}0.026) cGyh{sup -1} U{sup -1}, similar to the AAPM consensus values recommended currently for the Theragenics (Buford, GA) Model 200 (0.686{+-}0.033) cGyh{sup -1} U{sup -1}, the NASI (Chatsworth, CA) Model MED3633 (0.688{+-}0.033) cGyh{sup -1} U{sup -1}, and the Best Medical (Springfield, VA) Model 2335 (0.685{+-}0.033) cGyh{sup -1} U{sup -1} {sup 103}Pd sources. Conclusions: An independent {Lambda} determination has been performed for the Advantage Pd-103 source. The {sub PST}{Lambda} obtained in this work provides additional information needed for establishing a more accurate consensus {Lambda} value for the Advantage Pd-103 source.« less
78 FR 71609 - Methiocarb, Lambda-Cyhalothrin, Permethrin and Prodiamine; Notice of Receipt of Requests To...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-29

... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2009-1017; FRL-9902-77] Methiocarb, Lambda-Cyhalothrin... receipt of requests by the registrants to voluntarily amend their Methiocarb, Lambda- Cyhalothrin... Willowood Lambda Cyhalothrin LLC, Gowan Company, Farnam Companies, Inc., Pyxis Regulatory Consulting, Inc...

Structural relationship of curcumin derivatives binding to the BRCT domain of human DNA polymerase lambda.

PubMed

Takeuchi, Toshifumi; Ishidoh, Tomomi; Iijima, Hiroshi; Kuriyama, Isoko; Shimazaki, Noriko; Koiwai, Osamu; Kuramochi, Kouji; Kobayashi, Susumu; Sugawara, Fumio; Sakaguchi, Kengo; Yoshida, Hiromi; Mizushina, Yoshiyuki

2006-03-01

We previously reported that phenolic compounds, petasiphenol and curcumin (diferuloylmethane), were a selective inhibitor of DNA polymerase lambda (pol lambda) in vitro. The purpose of this study was to investigate the molecular structural relationship of curcumin and 13 chemically synthesized derivatives of curcumin. The inhibitory effect on pol lambda (full-length, i.e. intact pol lambda including the BRCA1 C- terminal [BRCT] domain) by some derivatives was stronger than that by curcumin, and monoacetylcurcumin (compound 13) was the strongest pol lambda inhibitor of all the compounds tested, achieving 50% inhibition at a concentration of 3.9 microm. The compound did not influence the activities of replicative pols such as alpha, delta, and epsilon. It had no effect on pol beta activity either, although the three-dimensional structure of pol beta is thought to be highly similar to that of pol lambda. Compound 13 did not inhibit the activity of the C-terminal catalytic domain of pol lambda including the pol beta-like core, in which the BRCT motif was deleted from its N-terminal region. MALDI-TOF MS analysis demonstrated that compound 13 bound selectively to the N-terminal domain of pol lambda, but did not bind to the C-terminal region. Based on these results, the pol lambda-inhibitory mechanism of compound 13 is discussed.
New 1982-1990 photometry of Lambda Andromedae and its 11-year cycle

NASA Technical Reports Server (NTRS)

Hall, Douglas S.; Henry, Gregory W.; Boehme, Dietmar; Brooks, Peter A.; Chang, Sandy; Dolzan, Ales; Fortier, George L.; Fried, Robert E.; Genet, Russell M.; Grim, Bruce S.

1991-01-01

The paper presents photoelectric photometry of Lambda And never before published, obtained between February 1982 and December 1990 at 29 different observatories. Then it is combined with all other photometry available (previously published, contained in the I.A.U. Commission 27 Archives, and obtained with the Vanderbilt 16-inch automatic telescope but not yet published), to yield a 14.8-year data base. Analysis reveals a long-term cycle in mean brightness, with a full range of 0.15 m and a period of 11.4 +/- 0.4 years. Because most of the new photometry was concentrated in the 1983-1984 observing season, this one well-defined light curve is analyzed with a two-spot model. Spot A keeps a 0.04 m amplitude throughout four rotation cycles whereas the amplitude of spot B diminishes from 0.09 m down almost to 0.03 m. The spot rotation periods were 55.9 d +/- 0.6 d and 52.8 d +/- 1.0 d, respectively.
Full-color laser cathode ray tube (L-CRT) projector

NASA Astrophysics Data System (ADS)

Kozlovskiy, Vladimir; Nasibov, Alexander S.; Popov, Yuri M.; Reznikov, Parvel V.; Skasyrsky, Yan K.

1995-04-01

A full color TV projector based on three laser cathode-ray tubes (L-CRT) is described. A water-cooled laser screen (LS) is the radiation element of the L-CRT. We have produced three main colors (blue, green and red) by using the LS made of three II-VI compounds: ZnSe ((lambda) equals 475 nm), CdS ((lambda) equals 530 nm) and ZnCdSe (630 nm). The total light flow reaches 1500 Lm, and the number of elements per line is not less than 1000. The LS efficiency may be about 10 Lm/W. In our experiments we have tested new electron optics: - (30 - 37) kV are applied to the cathode unit of the electron gun; the anode of the e-gun and the e-beam intensity modulator are under low potential; the LS has a potential + (30 - 37) kV. The accelerating voltage is divided into two parts, and this enables us to diminish the size and weight of the projector.
High-resolution IUE observations of the 1981 eclipse of 32 CYG

NASA Technical Reports Server (NTRS)

Reimers, D.; Che, A.; Hempe, K.

1981-01-01

32 Cyg shows a spectacular pure emission line spectrum during eclipse. Six weeks later, most lines, which were observed in emission during eclipse, are seen as P Cygni type profiles with strong absorption components. The lines are formed through line scattering of B star light in the extended atmosphere (wind) of the K supergiant. During eclipse, the emission parts of the P Cyg lines remain visible since the size of the line scattering sphere around the B star is larger than the red giant. Other emission lines are formed in a shock front near the B star (CIV, SiIV, FeIII) and possibly in an accretion disk. The strong FeII UV Mult. 191 lambda lambda 1785-88 A is shown to be formed through optical pumping via FeII UV Mult. 9 photons. The phase dependence of the P Cyg type profiles is modelled by means of line transfer calculations in nonspherical, 3-dimensional geometry with velocity fields.
Visual detection of trace nitroaromatic explosive residue using photoluminescent metallole-containing polymers.

PubMed

Toal, Sarah J; Sanchez, Jason C; Dugan, Regina E; Trogler, William C

2007-01-01

The detection of trace explosives is important for forensic, military, and homeland security applications. Detection of widely used nitroaromatic explosives (trinitrotoluene [TNT], 2,4-dinitrotoluene [DNT], picric acid [PA]) was carried out using photoluminescent metallole-containing polymers. The method of detection is through the quenching of fluorescence of thin films of the polymer, prepared by spray coating organic solutions of the polymer, by the explosive analyte. Visual quenching of luminescence (lambda(em) approximately 400-510 nm) in the presence of the explosive is seen immediately upon illumination with near-UV light (lambda(ex)=360 nm). Detection limits were observed to be as low as 5 ng for TNT, 20 ng for DNT, and 5 ng for PA. In addition, experiments with normal production line explosives and their components show that this technology is also able to detect composition B, Pyrodex, and nitromethane. This method offers a convenient and sensitive method of detection of trace nitroaromatic explosive residue.
New microscope produced by Lambda Praha Co. applicable to field studies of microorganisms.

PubMed

Zizka, Z

2008-01-01

A new microscope produced by the company Lambda Praha, applicable to field studies, was used for the observation of biofilms growing on stones and rocks of the Red Sea beach at Sharm El Sheikh resort in Egypt. The microscope was equipped with a novel LED illumination system, independent of sunlight as the light source, and an attachable mechanical stage making possible a precise and systematic observation of the preparation. Using this device, black biofilms of cyanobacteria and green biofilms of algae were studied; characteristic sheaths protecting the cells against the intense sunlight were found in cyanobacteria belonging to the genus Lyngbya. Trichomes on phylloids consisting of 3 to 4 cells were observed in algae belonging to the genus Padina, whose nuclei were degraded as a result of apoptosis, which is in contrast to the species Padina pavonia containing visible nuclear residues observed on the shore of the Mediterranean Sea near Lastovo island in Croatia in 2007.
Assessment of the bioequivalence of two formulations of clarithromycin extended-release 500-mg tablets under fasting and fed conditions: a single-dose, randomized, open-label, two-period, two-way crossover study in healthy Jordanian male volunteers.

PubMed

Alkhalidi, Bashar A; Tamimi, Jaafar J; Salem, Isam I; Ibrahim, Husain; Sallam, Alsayed Alarabi I

2008-10-01

Clarithromycin extended-release tablets are indicated for the treatment of adults with acute maxillary sinusitis caused by Haemophilus influenzae, Moraxella catarrhalis, or Streptococcus pneumoniae; acute bacterial exacerbation of chronic bronchitis due to H influenzae, Haemophilus parainfluenzae, M catarrhalis, or S pneumoniae; or community acquired pneumonia due to H influenzae, H parainfluenzae, M catarrhalis, S pneumoniae, Chlamydia pneumoniae, or Mycoplasma pneumoniae. This study was conducted to assess the bioequivalence of test and reference formulations of clarithromycin extended-release 500-mg tablets under fasting and fed conditions. This was a single-dose, randomized, open-label, 2-period, 2-way crossover study with a 1-week washout period between doses. Separate bioequivalence studies (fasting and fed) were performed in 2 groups of healthy male Jordanian volunteers. Eighteen blood samples were obtained from each volunteer over 38 hours after drug administration. Clarithromycin concentrations were determined in plasma using a validated high-performance liquid chromatography method with electrochemical detection. Pharmacokinetic parameters of clarithromycin (C(max), T(max), AUC(0-t), AUC(0-infinity), lambda(z) [first-order elimination rate constant], and t((1/2))) were calculated and analyzed statistically. Tolerability was assessed based on changes in vital signs and laboratory tests, and by questioning subjects about adverse events. Thirty-eight volunteers each participated in the fasting and fed studies. The mean ages of participants in the fasting and fed studies were 26.7 and 27.6 years, respectively; their mean weight was 71.2 and 70.9 kg and mean height was 171.3 and 179.0 cm. Under fasting conditions, the arithmetic mean (SD) C(max) was 569.4 (189.3) ng/mL for the test formulation and 641.2 (202.0) ng/mL for the reference formulation, with a geometric mean ratio of 0.88. The arithmetic mean AUC(0-t) was 8602.9 (4105.1) and 8245.3 (4122.4) ng . h/mL in the respective formulations, with a geometric mean ratio of 1.06. The arithmetic mean T(max) was 8.0 (5.6) and 6.1 (3.8) hours. In the fed study, the C(max) and AUC of both formulations were significantly increased relative to the fasting study (P < 0.05). The arithmetic mean C(max) of the 2 formulations was 1183.0 (637.5) and 1199.6 (496.3) ng/mL, with a geometric mean ratio of 0.93. The arithmetic mean AUC(0-t) was 12,981.2 (7849.0) and 11,822.9 (5790.2) ng . h/mL, with a geometric mean ratio of 1.06. The arithmetic mean T(max) was 5.7 (2.8) and 6.7 (2.5) hours. The 90% CI for the ratio (test:reference) of log-transformed C(max) and AUC values was within the acceptance range of 0.80 to 1.25. The 2 formulations were both well tolerated, and no adverse events were reported during the study. In these fasting and fed studies in healthy male Jordanian volunteers, the 2 formulations of clarithromycin extended-release 500-mg tablets were found to be bioequivalent according to the US Food and Drug Administration regulatory definition. Administration with food significantly increased the rate and extent of absorption of both products, with no significant effect on their bioequivalence.
Crystal Structure of Chabazite K

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

Yakubovich, O.V.; Gavrilenko, P.G.; Pekov, I.V.

2005-07-15

The crystal structure of the chabazite K with the formula (K{sub 1.33}Na{sub 1.02}Ca{sub 0.84})[Al{sub 4}Si{sub 8}O{sub 24}] {center_dot} 12.17H{sub 2}O from late hydrothermalites in the Khibiny alkaline massif (Kola Peninsula) is established by X-ray diffraction analysis (CAD4 four-circle diffractometer, {lambda}MoK{sub {alpha}} radiation, graphite monochromator, T = 193 K, 2{theta}{sub max} = 70 deg., R{sub 1} = 0.047 for 4745 reflections) on the basis of experimental data (6265 reflections) obtained from a twin (twinning parameter 0.535(1)): a = 13.831(3) A, c = 15.023(5) A, sp. gr. R3-barm, Z = 3, {rho}{sub calcd} = 2.016 g/cm{sup 3} . It is shown thatmore » cations occupy five independent positions in large cavities of the tetrahedral Al,Si,O anionic framework in potassium-rich chabazite. A comparative crystallochemical analysis of chabazites of different composition and origin is performed.« less
In vitro energy transfer in Renilla bioluminescence

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

Ward, W.W.; Cormier, M.J.

1976-09-23

A quantitative study of in vitro energy transfer in a natural biological system is reported. The in vitro bioluminescent oxidation of Renilla (sea pansy) luciferin by luciferase produces a broad, structureless emission, peaking in the blue at 490 nm. In contrast, the live animal produces a structured emission peaking in the green at 509 nm. This difference in emission characteristics is due to the presence, in Renilla, of a green fluorescent protein (GFP). Addition of GFP in vitro sensitizes the oxyluciferin product excited state, resulting in the narrow, structured green emission characteristic of GFP fluorescence (lambda/sub max/ 509 nm). Undermore » conditions of efficient in vitro energy transfer (2.7 x 10/sup -6/ M GFP) the radiative quantum yield (with respect to luciferin) increases 5.7-fold from 5.3% (blue pathway) to 30% (green pathway). The fluorescence quantum yield of the Renilla GFP has been measured as 30%; thus, within the precision of our measurements (15% coefficient of variation) the in vitro energy transfer efficiency is a surprising 100%.« less
A new test method for the evaluation of total antioxidant activity of herbal products.

PubMed

Zaporozhets, Olga A; Krushynska, Olena A; Lipkovska, Natalia A; Barvinchenko, Valentina N

2004-01-14

A new test method for measuring the antioxidant power of herbal products, based on solid-phase spectrophotometry using tetrabenzo-[b,f,j,n][1,5,9,13]-tetraazacyclohexadecine-Cu(II) complex immobilized on silica gel, is proposed. The absorbance of the modified sorbent (lambda(max) = 712 nm) increases proportionally to the total antioxidant activity of the sample solution. The method represents an attractive alternative to the mostly used radical scavenging capacity assays, because they generally require complex long-lasting stages to be carried out. The proposed test method is simple ("drop and measure" procedure is applied), rapid (10 min/sample), requires only the monitoring of time and absorbance, and provides good statistical parameters (s(r)
Resonance Raman spectra of the copper-sulfur chromophores in Achromobacter cycloclastes nitrite reductase.

PubMed

Dooley, D M; Moog, R S; Liu, M Y; Payne, W J; LeGall, J

1988-10-15

Resonance Raman spectroscopy at ambient temperature and 77 K has been used to probe the structures of the copper sites in Achromobacter cycloclastes nitrite reductase. This enzyme contains three copper ions per protein molecule and has two principal electronic absorption bands with lambda max values of 458 and 585 nm. Comparisons between the resonance Raman spectra of nitrite reductase and blue copper proteins establish that both the 458 and 585 nm bands are associated with Cu(II)-S(Cys) chromophores. A histidine ligand probably is also present. Different sets of vibrational frequencies are observed with 457.9 nm (ambient) or 476.1 nm (77 K) excitation as compared with 590 nm (ambient) or 593 nm (77 K) excitation. Excitation profiles indicate that the 458 and 585 nm absorption bands are associated with separate [Cu(II)-S(Cys)N(His)] sites or with inequivalent and uncoupled cysteine ligands in the same site. The former possibility is considered to be more likely.
Search for CP Violation in Hyperon Decay: $$\\Xi^- / \\bar{\\Xi}^+$$ and $$\\Lambda / \\bar{\\Lambda}$$ (in French)

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

Leros, Nicolas

2001-06-01

The HyperCP(EB71) experiment, performed at the Fermi National Accelerator Laboratory in the United States, provides a primary search for direct OP violation in the decays ofmore » $$\\Xi^-/\\bar{\\Xi}^+$$ and $$\\Lambda/ \\bar{\\Lambda}$$ hyperons....« less
Spectral sensitivity of the circadian system

NASA Astrophysics Data System (ADS)

Figueiro, Mariana G.; Bullough, John D.; Rea, Mark S.

2004-01-01

Light exposure regulates several circadian functions in normal humans including the sleep-wake cycle. Individuals with Alzheimer"s Disease (AD) often do not have regular patterns of activity and rest, but, rather, experience random periods of sleep and agitation during both day and night. Bright light during the day and darkness at night has been shown to consolidate activity periods during the day and rest periods at night in AD patients. The important characteristics of bright light exposure (quantity, spectrum, distribution, timing and duration) for achieving these results in AD patients is not yet understood. Recent research has shown that moderate (~18 lx at the cornea) blue (~470 nm) light is effective at suppressing melatonin in normal humans. It was hypothesized that blue light applied just before AD patients retire to their beds for the night would have a measurable impact on their behavior. A pilot study was conducted for 30 days in a senior health care facility using four individuals diagnosed with mild to moderate levels of dementia. Four AD patients were exposed to arrays of blue light from light emitting diodes (max wavelength = 470 nm) in two-hour sessions (18:00 to 20:00 hours) for 10 days. As a control, they were exposed to red light (max wavelength = 640 nm) in two-hour sessions for 10 days prior to the blue light exposure. Despite the modest sample size, exposure to blue LEDs has shown to affect sleep quality and median body temperature peak of these AD patients. Median body temperature peak was delayed by approximately 2 hours after exposure to blue LEDs compared to exposure to red LEDs and sleep quality was improved. This pilot study demonstrated that light, especially LEDs, can be an important contribution to helping AD patients regulate their circadian functions.
Luminescence properties and energy transfer of site-sensitive Ca(6-x-y)Mg(x-z)(PO(4))(4):Eu(y)(2+),Mn(z)(2+) phosphors and their application to near-UV LED-based white LEDs.

PubMed

Kwon, Ki Hyuk; Im, Won Bin; Jang, Ho Seong; Yoo, Hyoung Sun; Jeon, Duk Young

2009-12-21

On the basis of the structural information that the host material has excellent charge stabilization, blue-emitting Ca(6-x-y)Mg(x)(PO(4))(4):Eu(y)(2+) (CMP:Eu(2+)) phosphors were synthesized and systematically optimized, and their photoluminescence (PL) properties were evaluated. Depending upon the amount of Mg added, the emission efficiency of the phosphors could be enhanced. The substitution of Eu(2+) affected their maximum wavelength (lambda(max)) and thermal stability because the substitution site of Eu(2+) could be varied. To obtain single-phase two-color-emitting phosphors, we incorporated Mn(2+) into CMP:Eu(2+) phosphors. Weak red emission resulting from the forbidden transition of Mn(2+) could be enhanced by the energy transfer from Eu(2+) to Mn(2+) that occurs because of the spectral overlap between the photoluminescence excitation (PLE) spectrum of Mn(2+) and the PL spectrum of Eu(2+). The energy transfer process was confirmed by the luminescence spectra, energy transfer efficiency, and decay curve of the phosphors. Finally, the optimized Ca(6-x-y)Mg(x-z)(PO(4))(4):Eu(y)(2+),Mn(z)(2+) (CMP:Eu(2+),Mn(2+)) phosphors were applied with green emitting Ca(2)MgSi(2)O(7):Eu(2+) (CMS:Eu(2+)) phosphors to ultraviolet (UV) light emitting diode (LED)-pumped white LEDs. The CMS:Eu(2+)-mixed CMP:Eu(2+), Mn(2+)-based white LEDs showed an excellent color rendering index (CRI) of 98 because of the broader emission band and more stable color coordinates than those of commercial Y(3)Al(5)O(12):Ce(3+) (YAG:Ce(3+))-based white LEDs under a forward bias current of 20 mA. The fabricated white LEDs showed very bright natural white light that had the color coordinate of (0.3288, 0.3401), and thus CMP:Eu(2+),Mn(2+) could be regarded as a good candidate for UV LED-based white LEDs.
Photosynthetic and Growth Response of Sugar Maple (Acer saccharum Marsh.) Mature Trees and Seedlings to Calcium, Magnesium, and Nitrogen Additions in the Catskill Mountains, NY, USA.

PubMed

Momen, Bahram; Behling, Shawna J; Lawrence, Greg B; Sullivan, Joseph H

2015-01-01

Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor, which can impede seedling survival.
Photosynthetic and Growth Response of Sugar Maple (Acer saccharum Marsh.) Mature Trees and Seedlings to Calcium, Magnesium, and Nitrogen Additions in the Catskill Mountains, NY, USA

PubMed Central

Momen, Bahram; Behling, Shawna J.; Lawrence, Greg B.; Sullivan, Joseph H.

2015-01-01

Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (A qe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; A qe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor, which can impede seedling survival. PMID:26291323
Photosynthetic and growth response of sugar maple (Acer saccharum Marsh.) mature trees and seedlings to calcium, magnesium, and nitrogen additions in the Catskill Mountains, NY, USA

USGS Publications Warehouse

Momen, Bahram; Behling, Shawna J; Lawrence, Gregory B.; Sullivan, Joseph H

2015-01-01

Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor, which can impede seedling survival.
Prognostic value of the serum free light chain ratio in newly diagnosed myeloma: proposed incorporation into the international staging system.

PubMed

Snozek, C L H; Katzmann, J A; Kyle, R A; Dispenzieri, A; Larson, D R; Therneau, T M; Melton, L J; Kumar, S; Greipp, P R; Clark, R J; Rajkumar, S V

2008-10-01

To determine if the serum free light chain (FLC) ratio has prognostic value in patients with symptomatic multiple myeloma (MM), baseline serum samples from a well-characterized cohort of 790 newly diagnosed MM patients were tested with the FLC assay. FLC ratio was calculated as kappa/lambda (reference range 0.26-1.65). On the basis of the distribution of values, a cutpoint kappa/lambda FLC ratio of <0.03 or >32 was chosen for further analysis. Overall survival was significantly inferior in patients with an abnormal FLC ratio of <0.03 or >32 (n=479) compared with those with an FLC ratio between 0.03 and 32 (n=311), with median survival of 30 versus 39 months, respectively. We incorporated abnormal FLC ratio with the International Staging System (ISS) risk factors (that is, albumin <3.5 g/dl and serum beta(2)-microglobulin >or=3.5 g/l), to create a risk stratification model with improved prognostic capabilities. Patients with 0, 1, 2 or 3 adverse risk factors had significantly different overall survival, with median survival times of 51, 39, 30 and 22 months, respectively (P<0.001). These findings suggest that the serum FLC ratio at initial diagnosis is an important predictor of prognosis in myeloma, and can be incorporated into the ISS for improved risk stratification.
Bubble formation during pulsed laser ablation: mechanism and implications

NASA Astrophysics Data System (ADS)

van Leeuwen, Ton G. J. M.; Jansen, E. Duco; Motamedi, Massoud; Welch, Ashley J.; Borst, Cornelius

1993-07-01

Holmium ((lambda) equals 2.09 micrometers ) and excimer ((lambda) equals 308 nm) lasers are used for ablation of tissue. In a previous study it was demonstrated that both excimer and holmium laser pulses produce fast expanding and collapsing vapor bubbles. To investigate whether the excimer induced bubble is caused by vaporization of water, the threshold fluence for bubble formation at a bare fiber tip in water was compared between the excimer laser (pulse length 115 ns) and the Q-switched and free-running holmium lasers (pulse length 1 microsecond(s) to 250 microsecond(s) , respectively). To induce bubble formation by excimer laser light in water, the absorber oxybuprocaine-hydrochloride (OBP-HCl) was added to the water. Fast flash photography was used to measure the threshold fluence as a function of the water temperature (6 - 90 degree(s)C) at environmental pressure. The ultraviolet excimer laser light is strongly absorbed by blood. Therefore, to document the implications of bubble formation at fluences above the tissue ablation threshold, excimer laser pulses were delivered in vitro in hemoglobin solution and in vivo in the femoral artery of the rabbit. We conclude that the principal content of the fast bubble induced by a 308 nm excimer laser pulse is water vapor. Therefore, delivery of excimer laser pulses in a water or blood environment will cause fast expanding water vapor bubbles, which may induce mechanical damage to adjacent tissue.
TESTING NONSTANDARD COSMOLOGICAL MODELS WITH SNLS3 SUPERNOVA DATA AND OTHER COSMOLOGICAL PROBES

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

Li Zhengxiang; Yu Hongwei; Wu Puxun, E-mail: hwyu@hunnu.edu.cn

2012-01-10

We investigate the implications for some nonstandard cosmological models using data from the first three years of the Supernova Legacy Survey (SNLS3), assuming a spatially flat universe. A comparison between the constraints from the SNLS3 and those from other SN Ia samples, such as the ESSENCE, Union2, SDSS-II, and Constitution samples, is given and the effects of different light-curve fitters are considered. We find that analyzing SNe Ia with SALT2 or SALT or SiFTO can give consistent results and the tensions between different data sets and different light-curve fitters are obvious for fewer-free-parameters models. At the same time, we alsomore » study the constraints from SNLS3 along with data from the cosmic microwave background and the baryonic acoustic oscillations (CMB/BAO), and the latest Hubble parameter versus redshift (H(z)). Using model selection criteria such as {chi}{sup 2}/dof, goodness of fit, Akaike information criterion, and Bayesian information criterion, we find that, among all the cosmological models considered here ({Lambda}CDM, constant w, varying w, Dvali-Gabadadze-Porrati (DGP), modified polytropic Cardassian, and the generalized Chaplygin gas), the flat DGP is favored by SNLS3 alone. However, when additional CMB/BAO or H(z) constraints are included, this is no longer the case, and the flat {Lambda}CDM becomes preferred.« less

Achromatic Focal Plane Mask for Exoplanet Imaging Coronagraphy

NASA Technical Reports Server (NTRS)

Newman, Kevin Edward; Belikov, Ruslan; Guyon, Olivier; Balasubramanian, Kunjithapatham; Wilson, Dan

2013-01-01

Recent advances in coronagraph technologies for exoplanet imaging have achieved contrasts close to 1e10 at 4 lambda/D and 1e-9 at 2 lambda/D in monochromatic light. A remaining technological challenge is to achieve high contrast in broadband light; a challenge that is largely limited by chromaticity of the focal plane mask. The size of a star image scales linearly with wavelength. Focal plane masks are typically the same size at all wavelengths, and must be sized for the longest wavelength in the observational band to avoid starlight leakage. However, this oversized mask blocks useful discovery space from the shorter wavelengths. We present here the design, development, and testing of an achromatic focal plane mask based on the concept of optical filtering by a diffractive optical element (DOE). The mask consists of an array of DOE cells, the combination of which functions as a wavelength filter with any desired amplitude and phase transmission. The effective size of the mask scales nearly linearly with wavelength, and allows significant improvement in the inner working angle of the coronagraph at shorter wavelengths. The design is applicable to almost any coronagraph configuration, and enables operation in a wider band of wavelengths than would otherwise be possible. We include initial results from a laboratory demonstration of the mask with the Phase Induced Amplitude Apodization coronagraph.
New SPUDT cell structures.

PubMed

Martin, Guenter; Schmidt, Hagen; Wall, Bert

2004-07-01

The present paper describes single-phase unidirectional transducers (SPUDT) cells with all fingers wider than lambda/8 while maintaining the unidirectional effect. The first solution is related to a SPUDT consisting of lambda/4 and lambda/2 wide fingers arranged in two tracks. Each track has no significant unidirectional effect. Both tracks form a waveguide, and the waveguide coupling generates the interaction of the tracks. As a result of that interaction, a unidirectional effect arises as verified by experiment. This transducer type is called double-track (DT) SPUDT. A second solution is suggested that includes, in contrast to distributed acoustic reflection transducer (DART), electrode width control (EWC), and Hunsinger cells, SPUDT cell fingers with one and the same width only. Cell types with lambda/6, lambda/5, and lambda/3 wide fingers called uniform width electrode (UWE) cells are considered. One of these cell types, including exclusively lambda/5 wide fingers, is experimentally investigated and a unidirectional effect is found. Moreover, a filter example using the lambda/5 cell type has been designed for reducing SPUDT reflections. The echo suppression expected could be verified experimentally. No waveguide coupling is required for this cell type.
Recombination between bacteriophage lambda and plasmid pBR322 in Escherichia coli.

PubMed Central

Pogue-Geile, K L; Dassarma, S; King, S R; Jaskunas, S R

1980-01-01

Recombinant lambda phages were isolated that resulted from recombination between the lambda genome and plasmid pBR322 in Escherichia coli, even though these deoxyribonucleic acids (DNAs) did not share extensive regions of homology. The characterization of these recombinant DNAs by heteroduplex analysis and restriction endonucleases is described. All but one of the recombinants appeared to have resulted from reciprocal recombination between a site on lambda DNA and a site on the plasmid. In general, there were two classes of recombinants. One class appeared to have resulted from recombination at the phage attachment site that probably resulted from lambda integration into secondary attachment sites on the plasmid. Seven different secondary attachment sites on pBR322 were found. The other class resulted from plasmid integration at other sites that were widely scattered on the lambda genome. For this second class of recombinants, more than one site on the plasmid could recombine with lambda DNA. Thus, the recombination did not appear to be site specific with respect to lambda or the plasmid. Possible mechanisms for generating these recombinants are discussed. Images PMID:6247334
Two-parameter partially correlated ground-state electron density of some light spherical atoms from Hartree-Fock theory with nonintegral nuclear charge

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

Cordero, Nicolas A.; March, Norman H.; Alonso, Julio A.

2007-05-15

Partially correlated ground-state electron densities for some spherical light atoms are calculated, into which nonrelativistic ionization potentials represent essential input data. The nuclear cusp condition of Kato is satisfied precisely. The basic theoretical starting point, however, is Hartree-Fock (HF) theory for the N electrons under consideration but with nonintegral nuclear charge Z{sup '} slightly different from the atomic number Z (=N). This HF density is scaled with a parameter {lambda}, near to unity, to preserve normalization. Finally, some tests are performed on the densities for the atoms Ne and Ar, as well as for Be and Mg.
Electro-Optic Lighting Detector

NASA Technical Reports Server (NTRS)

Koshak, William J.; Solakiewicz, Richard J.

1999-01-01

The design, alignment, calibration, and field deployment of a solid-state lightning detector is described. The primary sensing component of the detector is a potassium dihydrogen phosphate electro-optic crystal that is attached in series to a flat-plate aluminum antenna; the antenna is exposed to the ambient thundercloud electric field. A semiconductor laser diode (lambda = 685 nm), polarizing optics, and the crystal are arranged in a Pockels cell configuration. Lightning-caused electric field changes are related to small changes in the transmission of laser light through the optical cell. Several hundred lightning electric field change excursions were recorded during five thunderstorms that occurred in the summer of 1998 at the NASA Marshall Space Flight Center in northern Alabama.
Elevated carboxylesterase activity contributes to the lambda-cyhalothrin insensitivity in quercetin fed Helicoverpa armigera (Hübner).

PubMed

Chen, Chengyu; Liu, Ying; Shi, Xueyan; Desneux, Nicolas; Han, Peng; Gao, Xiwu

2017-01-01

Quercetin as one of the key plant secondary metabolite flavonol is ubiquitous in terrestrial plants. In this study, the decrease in sensitivity to lambda-cyhalothrin was observed in quercetin-fed Helicoverpa armigera larvae. In order to figure out the mechanisms underlying the decreased sensitivity of H. armigera larvae to lambda-cyhalothrin by quercetin induction, the changes in carboxylesterase activity and in-vitro hydrolytic metabolic capacity to lambda-cyhalothrin were examined. The LC50 value of quercetin-fed H. armigera larvae to lambda-cyhalothrin showed 2.41-fold higher than that of the control. S, S, S-Tributyl phosphorotrithioate (DEF) treatment showed a synergism effect on lambda-cyhalothrin toxicity to quercetin-fed H. armigera. Moreover, the activity of carboxylesterase was significantly higher in quercetin-fed H. armigera larvae after fed on quercetin for 48 h. The in-vitro hydrolytic metabolic capacity to lambda-cyhalothrin in quercetin-fed H. armigera larvae midgut was 289.82 nmol 3-PBA/mg protein/min, which is significant higher than that in the control group (149.60 nmol 3-PBA/mg protein/min). The elevated CarE enzyme activity and corresponding increased hydrolytic metabolic capacity to lambda-cyhalothrin in quercetin-fed H. armigera contributed to the enhanced tolerance to lambda-cyhalothrin.
Elevated carboxylesterase activity contributes to the lambda-cyhalothrin insensitivity in quercetin fed Helicoverpa armigera (Hübner)

PubMed Central

Chen, Chengyu; Liu, Ying; Desneux, Nicolas; Han, Peng; Gao, Xiwu

2017-01-01

Quercetin as one of the key plant secondary metabolite flavonol is ubiquitous in terrestrial plants. In this study, the decrease in sensitivity to lambda-cyhalothrin was observed in quercetin-fed Helicoverpa armigera larvae. In order to figure out the mechanisms underlying the decreased sensitivity of H. armigera larvae to lambda-cyhalothrin by quercetin induction, the changes in carboxylesterase activity and in-vitro hydrolytic metabolic capacity to lambda-cyhalothrin were examined. The LC50 value of quercetin-fed H. armigera larvae to lambda-cyhalothrin showed 2.41-fold higher than that of the control. S, S, S-Tributyl phosphorotrithioate (DEF) treatment showed a synergism effect on lambda-cyhalothrin toxicity to quercetin-fed H. armigera. Moreover, the activity of carboxylesterase was significantly higher in quercetin-fed H. armigera larvae after fed on quercetin for 48 h. The in-vitro hydrolytic metabolic capacity to lambda-cyhalothrin in quercetin-fed H. armigera larvae midgut was 289.82 nmol 3-PBA/mg protein/min, which is significant higher than that in the control group (149.60 nmol 3-PBA/mg protein/min). The elevated CarE enzyme activity and corresponding increased hydrolytic metabolic capacity to lambda-cyhalothrin in quercetin-fed H. armigera contributed to the enhanced tolerance to lambda-cyhalothrin. PMID:28817718
A triple helical calcium-based coordination polymer with strong blue fluorescent emission

NASA Astrophysics Data System (ADS)

Yu, Liang-Cai; Chen, Zhen-Feng; Liang, Hong; Zhou, Chun-Shan; Li, Yan

2005-08-01

A hydrothermal reaction of 1,3-dicyanobenzene and Ca(OH)2 yielded a triple helical calcium-based coordination polymer of the formula, C20H25Ca2.50O18.50 (1). The 1,3-benzenecarboxylate anion, found in the final product was generated in situ during the synthesis by the hydrolysis of 1,3-dicyanobenzene. X-ray diffraction study shows that the complex 1 crystallizes in the monoclinic system, C2/c space group, a=15.5701(5), b=21.4445(7), c=17.1601(6) Å, β=111.7400(7)°, V=5322.1(3) Å3, Z=8, Dc=1.651 Mg/m3. The calcium atoms show differences in the coordination environments. Complex 1 emits strong blue fluorescent light (λem(max)=419 nm) when it is excited by UV light (λex(max)=316 nm) in the solid state at room temperature.
Thermal-mechanical fatigue crack growth in Inconel X-750

NASA Technical Reports Server (NTRS)

Marchand, N.; Pelloux, R. M.

1984-01-01

Thermal-mechanical fatigue crack growth (TMFCG) was studied in a gamma-gamma' nickel base superalloy Inconel X-750 under controlled load amplitude in the temperature range from 300 to 650 C. In-phase (T sub max at sigma sub max), out-of-phase (T sub min at sigma sub max), and isothermal tests at 650 C were performed on single-edge notch bars under fully reversed cyclic conditions. A dc electrical potential method was used to measure crack length. The electrical potential response obtained for each cycle of a given wave form and R value yields information on crack closure and crack extension per cycle. The macroscopic crack growth rates are reported as a function of delta k and the relative magnitude of the TMFCG are discussed in the light of the potential drop information and of the fractographic observations.
Antitumor activity of type I and type III interferons in BNL hepatoma model.

PubMed

Abushahba, Walid; Balan, Murugabaskar; Castaneda, Ismael; Yuan, Yao; Reuhl, Kenneth; Raveche, Elizabeth; de la Torre, Andrew; Lasfar, Ahmed; Kotenko, Sergei V

2010-07-01

Hepatocellular carcinoma (HCC) occurs most commonly secondary to cirrhosis due to chronic hepatitis C or B virus (HCV/HBV) infections. Type I interferon (IFN-alpha) treatment of chronic HCV/HBV infections reduces the incidence of HCC in cirrhotic patients. However, IFN-alpha toxicity limits its tolerability and efficacy highlighting a need for better therapeutic treatments. A recently discovered type III IFN (IFN-lambda) has been shown to possess antiviral properties against HCV and HBV in vitro. In phase I clinical trials, IFN-lambda treatment did not cause significant adverse reactions. Using a gene therapy approach, we compared the antitumor properties of IFN-alpha and IFN-lambda in a transplantable hepatoma model of HCC. BALB/c mice were inoculated with syngeneic BNL hepatoma cells, or BNL cells expressing IFN-lambda (BNL.IFN-lambda cells) or IFN-alpha (BNL.IFN-alpha cells). Despite the lack of antiproliferative activity of IFNs on BNL cells, both BNL.IFN-lambda and BNL.IFN-alpha cells displayed retarded growth kinetics in vivo. Depletion of NK cells from splenocytes inhibited splenocyte-mediated cytotoxicity, demonstrating that NK cells play a role in IFN-induced antitumor responses. However, isolated NK cells did not respond directly to IFN-lambda. There was also a marked NK cell infiltration in IFN-lambda producing tumors. In addition, IFN-lambda and, to a lesser extent, IFN-alpha enhanced immunocytotoxicity of splenocytes primed with irradiated BNL cells. Splenocyte cytotoxicity against BNL cells was dependent on IL-12 and IFN-gamma, and mediated by dendritic cells. In contrast to NK cells, isolated from spleen CD11c+ and mPDCA+ dendritic cells responded directly to IFN-lambda. The antitumor activities of IFN-lambda against hepatoma, in combination with HCV and HBV antiviral activities warrant further investigation into the clinical use of IFN-lambda to prevent HCC in HCV/HBV-infected cirrhotic patients, as well as to treat liver cancer.
Cyclometalated 6-phenyl-2,2'-bipyridyl (CNN) platinum(II) acetylide complexes: structure, electrochemistry, photophysics, and oxidative- and reductive-quenching studies.

PubMed

Schneider, Jacob; Du, Pingwu; Jarosz, Paul; Lazarides, Theodore; Wang, Xiaoyong; Brennessel, William W; Eisenberg, Richard

2009-05-18

Three cyclometalated 6-phenyl-4-(p-R-phenyl)-2,2'-bipyridyl (CNN-Ph-R) Pt(II) acetylide complexes, Pt(CNN-Ph-R)(CCPh), where R = Me (1), COOMe (2), and P(O)(OEt)(2) (3), have been synthesized and studied. Compounds 1 and 3 have been structurally characterized by single crystal X-ray crystallography and are found to exhibit distorted square planar geometries about the Pt(II) ions. The electrochemical properties of the compounds, as determined by cyclic voltammetry, have also been examined. Complexes 1-3 are brightly emissive in fluid CH(2)Cl(2) solution and in the solid state with lambda(em)(max) of ca. 600 nm and lifetimes on the order of ca. 500 ns in fluid solution. The emissions are assigned to a (3)MLCT transition. The complexes undergo oxidative quenching by MV(2+) with quenching rates near the diffusion-controlled limit (k(q) approximately 1.4 x 10(10) M(-1) s(-1)) in CH(2)Cl(2) solution. Reductive-quenching experiments of complexes 1-3 by the amine donors N,N,N',N'-tetramethylphenylenediamine (TMPD), phenothiazine (PTZ), and N,N,N',N'-tetramethylbenzidine (TMB) follow Stern-Volmer behavior, with very fast quenching rates on the order of 10(9)-10(10) M(-1) s(-1) in CH(2)Cl(2) solution. When the complexes are employed as the sensitizer in multiple component systems containing MV(2+), TEOA, and colloidal Pt in aqueous media, approximately one turnover of H(2) (TN vs mol of chromophore) is produced per hour upon irradiation with lambda > 410 nm but only after at least a 2 h induction period.
Parametric binary dissection

NASA Technical Reports Server (NTRS)

Bokhari, Shahid H.; Crockett, Thomas W.; Nicol, David M.

1993-01-01

Binary dissection is widely used to partition non-uniform domains over parallel computers. This algorithm does not consider the perimeter, surface area, or aspect ratio of the regions being generated and can yield decompositions that have poor communication to computation ratio. Parametric Binary Dissection (PBD) is a new algorithm in which each cut is chosen to minimize load + lambda x(shape). In a 2 (or 3) dimensional problem, load is the amount of computation to be performed in a subregion and shape could refer to the perimeter (respectively surface) of that subregion. Shape is a measure of communication overhead and the parameter permits us to trade off load imbalance against communication overhead. When A is zero, the algorithm reduces to plain binary dissection. This algorithm can be used to partition graphs embedded in 2 or 3-d. Load is the number of nodes in a subregion, shape the number of edges that leave that subregion, and lambda the ratio of time to communicate over an edge to the time to compute at a node. An algorithm is presented that finds the depth d parametric dissection of an embedded graph with n vertices and e edges in O(max(n log n, de)) time, which is an improvement over the O(dn log n) time of plain binary dissection. Parallel versions of this algorithm are also presented; the best of these requires O((n/p) log(sup 3)p) time on a p processor hypercube, assuming graphs of bounded degree. How PBD is applied to 3-d unstructured meshes and yields partitions that are better than those obtained by plain dissection is described. Its application to the color image quantization problem is also discussed, in which samples in a high-resolution color space are mapped onto a lower resolution space in a way that minimizes the color error.
A randomized, controlled study of peginterferon lambda-1a/ribavirin ± daclatasvir for hepatitis C virus genotype 2 or 3.

PubMed

Foster, Graham R; Chayama, Kazuaki; Chuang, Wan-Long; Fainboim, Hugo; Farkkila, Martti; Gadano, Adrian; Gaeta, Giovanni B; Hézode, Christophe; Inada, Yukiko; Heo, Jeong; Kumada, Hiromitsu; Lu, Sheng-Nan; Marcellin, Patrick; Moreno, Christophe; Roberts, Stuart K; Strasser, Simone I; Thompson, Alexander J; Toyota, Joji; Paik, Seung Woon; Vierling, John M; Zignego, Anna L; Cohen, David; McPhee, Fiona; Wind-Rotolo, Megan; Srinivasan, Subasree; Hruska, Matthew; Myler, Heather; Portsmouth, Simon D

2016-01-01

Peginterferon Lambda was being developed as an alternative to alfa interferon for the treatment of chronic hepatitis C virus (HCV) infection. We compared peginterferon Lambda-1a plus ribavirin (Lambda/RBV) and Lambda/RBV plus daclatasvir (DCV; pangenotypic NS5A inhibitor) with peginterferon alfa-2a plus RBV (alfa/RBV) in treatment-naive patients with HCV genotype 2 or 3 infection. In this multicenter, double-blind, phase 3 randomized controlled trial, patients were assigned 2:2:1 to receive 24 weeks of Lambda/RBV, 12 weeks of Lambda/RBV + DCV, or 24 weeks of alfa/RBV. The primary outcome measure was sustained virologic response at post-treatment Week 12 (SVR12). Overall, 874 patients were treated: Lambda/RBV, n = 353; Lambda/RBV + DCV, n = 349; alfa/RBV, n = 172. Patients were 65 % white and 33 % Asian, 57 % male, with a mean age of 47 years; 52 % were infected with genotype 2 (6 % cirrhotic) and 48 % with genotype 3 (9 % cirrhotic). In the Lambda/RBV + DCV group, 83 % (95 % confidence interval [CI] 78.5, 86.5) achieved SVR12 (90 % genotype 2, 75 % genotype 3) whereas SVR12 was achieved by 68 % (95 % CI 63.1, 72.9) with Lambda/RBV (72 % genotype 2, 64 % genotype 3) and 73 % (95 % CI 66.6, 79.9) with peginterferon alfa/RBV (74 % genotype 2, 73 % genotype 3). Lambda/RBV + DCV was associated with lower incidences of flu-like symptoms, hematological abnormalities, and discontinuations due to adverse events compared with alfa/RBV. The 12-week regimen of Lambda/RBV + DCV was superior to peginterferon alfa/RBV in the combined population of treatment-naive patients with genotype 2 or 3 infection, with an improved tolerability and safety profile compared with alfa/RBV.
Dynamic processes in Be star atmospheres. 2: He I 2P-nD line formation in lambda Eridani (outburst)

NASA Technical Reports Server (NTRS)

Smith, Myron A.; Hubeny, Ivan; Lanz, Thierry; Meylan, Thomas

1994-01-01

The He I lambda 6678 line of early Be stars generally shows violet (V) and red (R) emission whenever hydrogen alpha emission is present, but its use as a diagnostic has been handicapped by a poor understanding of the processes that drive it into emission. In an attempt to address this problem we obtained three series of eschelle spectra of the first two members of the singlet and triplet 2P-nD series of lambda Eri (B2e) during 1992 November 3-5 at Kitt Peak. During these observations lambda 6678 showed substantial emission variability in both the wings and central profile, providing an opportunity to compare its behavior with that of the lambda 4922, lambda 5876, and lambda 4471 lines. We found that the responses of the lines were different in several respects. Whereas the emissions in the V wings of all four lines scaled together, the R wing of the lambda 4922 line invariably responded with increased absorption whenever the R wing of lambda 6678 line showed increased emission. These same trends occurred within the central photospheric profiles. The R-wing behavior shows that much, but not all of the emission in lambda 6678 is caused by matter projected against the stellar disk. The excitation temperatures of the neighboring 2(sup 1) P transitions, lambda 6678 and lambda 4922 must be greater than and less than the photospheric continuum temperature, respectively. We have investigated departures from local thermodynamic equilibrium (LTE) for the He I spectrum in a variety of ad hoc, perturbed model atmospheres. We have found only one way to cause the source function of lambda 6678 to increase so strongly, namely, by increasing the atmospheric temperature in the line formation region to 30,000 - 40,000 K. This effect was discovered by Auer and Mihalas for O3-O4 atmospheric models, but it has not been applied to active B stars. Our models suggest that lambda 6678 emission in Be stars can be used as a sensitive monitor of localized hot spots on these stars' surfaces. The energies involved in heating the active portions of the atmosphere are too high to be produced by gravitational infall. This leaves magnetically induced flares among the few known processes on the surfaces of stars capable of sustaining this energy level.
Physical Strain and Work Ergonomics in Farmers with Disabilities.

PubMed

Nevala-Puranen, Nina; Sörensen, Lars

1997-01-01

In agriculture, occupational injuries are common, and several of them lead to permanent physical disability. The objective of this case study was to assess the strain and the ergonomic needs of four farmers (aged 34-49 years) with physical disabilities. A maximal bicycle ergometer test or an arm-crank test was done to assess their maximal heart rate (HR max ) and maximal oxygen consumption (V0 2max ). The strain at work was analyzed by measuring heart rate (HR), muscle activity (EMG), and the rating of perceived exertion (RPE). The farmers were interviewed as to possible and impossible work tasks and the ergonomic redesign measures taken to improve the work environment. The work tasks performed were mainly light or moderate work for the cardiorespiratory system according to mean HR (88-102 beats/min), the percentage of HR range (17-31% HRR), and the relative V0 2 (22-46% V0 2max ). The mean activity of the trapezius muscles was 0.4-9% of the maximal voluntary contraction (%MVC). All the participants had work tasks they were unable to perform. They had made ergonomie redesign changes mainly to the tractor. This case study showed that some agricultural work tasks were possible for farmers with physical disabilities and that the physical strain associated with these tasks was mainly light or moderate.
Magnetic penetration depth of YBa2Cu3O(7-delta) thin films determined by the power transmission method

NASA Technical Reports Server (NTRS)

Heinen, Vernon O.; Miranda, Felix A.; Bhasin, Kul B.

1992-01-01

A power transmission measurement technique was used to determine the magnetic penetration depth (lambda) of YBa2Cu3O(7-delta) superconducting thin films on LaAlO3 within the 26.5 to 40.0 GHz frequency range, and at temperatures from 20 to 300 K. Values of lambda ranging from 1100 to 2500 A were obtained at low temperatures. The anisotropy of lambda was determined from measurements of c-axis and a-axis oriented films. An estimate of the intrinsic value of lambda of 90 +/- 30 nm was obtained from the dependence of lambda on film thickness. The advantage of this technique is that it allows lambda to be determined nondestructively.
Measurement of the Branching Ratio Lambda_c+ -> p pi+ pi- (in Spanish)

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

Lopez-Hinojosa, Guillermo; /San Luis Potosi U.

2008-03-01

The confirmation of the Cabibbo-suppressed charm baryon decay mode {Lambda}{sub c}{sup +} {yields} p{pi}{sup +}{pi}{sup -} is reported. All data analyzed are from SELEX, a fixed target experiment at Fermilab that took data during 1996 and 1997, mainly with a 600 GeV/c {Sigma}{sup -} beam. The branching ratio of the Cabibbo-suppressed decay mode {Lambda}{sub c}{sup +} {yields} p{pi}{sup +}{pi}{sup -} relative to the Cabibbo-favored mode {Lambda}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +} is measured to be: {Gamma}({Lambda}{sub c}{sup +} {yields} p{pi}{sup +}{pi}{sup -})/{Gamma}({Lambda}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +}) = 0.103 {+-} 0.022.
Changes in bacterial diversity and community structure following pesticides addition to soil estimated by cultivation technique.

PubMed

Cycoń, Mariusz; Piotrowska-Seget, Zofia

2009-07-01

An experiment was conducted under laboratory conditions to investigate the effect of increasing concentrations of fenitrothion (2, 10 and 200 mg a.i./kg soil), diuron (1.5, 7.5 and 150 mg a.i./kg soil) and thiram (3.5, 17.5 and 350 mg a.i./kg soil) on soil respiration, bacterial counts and changes in culturable fraction of soil bacteria. To ascertain these changes, the community structure, bacterial biodiversity and process of colony formation, based on the r/K strategy concept, EP- and CD-indices and the FOR model, respectively, were determined. The results showed that the measured parameters were generally unaffected by the lowest dosages of pesticides, corresponding to the recommended field rates. The highest dosages of fenitrothion and thiram suppressed the peak SIR by 15-70% and 20-80%, respectively, while diuron increased respiration rate by 17-25% during the 28-day experiment. Also, the total numbers of bacteria increased in pesticide-treated soils. However, the reverse effect on day 1 and, in addition, in case of the highest dosages of insecticide on days 14 and 28, was observed. Analysis of the community structure revealed that in all soil treatments bacterial communities were generally dominated by K-strategists. Moreover, differences in the distribution of individual bacteria classes and the gradual domination of bacteria populations belonging to r-strategists during the experiment, as compared to control, was observed. However, on day 1, at the highest pesticide dosages, fast growing bacteria constituted only 1-10% of the total colonies number during 48 h of plate incubation, whereas in remaining samples they reached from 20 to 40% of total cfu. This effect, in case of fenitrothion, lasted till the end of the experiment. At the highest dosages of fenitrothion, diuron and at all dosages of thiram the decrease of biodiversity, as indicated by EP- and CD-indices on day 1, was found. At the next sampling time, no significant retarding or stimulating effect was detected. However, in case of CD values the higher differences were observed. The significant impact of pesticides on the physiological state of soil bacteria was not found. They were generally in dormant state (lambda < 0.5), but immediately after pesticides application, the additional reduction of frequency of bacterial cell proliferation (max. decrease of lambda value to 0.15 for thiram on day 14) and prolonged retardation time of colony appearance (max. increase of t(r) value to 1.39 for fenitrothion on day 1) on agar plates were found.
Radiation and quantum chemical studies of chalcone derivatives.

PubMed

Gaikwad, P; Priyadarsini, K I; Naumov, S; Rao, B S M

2010-08-05

The reactions of oxidizing radicals ((*)OH, Br(2)(*-), and SO(4)(*-)) with -OH-, -CH(3)-, or -NH(2)-substituted indole chalcones and hydroxy benzenoid chalcones were studied by radiation and quantum chemical methods. The (*)OH radical was found to react by addition at diffusion-controlled rates (k = 1.1-1.7 x 10(10) dm(3) mol(-1) s(-1)), but Br(2)(*-) radical reacted by 2 orders of magnitude lower. Quantum chemical calculations at the B3LYP/6-31+G(d,p) level of theory have shown that the (C2-OH)(*), (C11-OH)(*), and (C10-OH)(*) adducts of the indole chalcones and the (C7-OH)(*) and (C8-OH)(*) adducts of the hydroxy benzenoid chalcones are more stable with DeltaH = -39 to -28 kcal mol(-1) and DeltaG = -32 to -19 kcal mol(-1). This suggests that (*)OH addition to the alpha,beta-unsaturated bond is a major reaction channel in both types of chalcones and is barrierless. The stability and lack of dehydration of the (*)OH adducts arise from two factors: strong frontier orbital interaction due to the low energy gap between interacting orbitals and the negligible Coulombic repulsion due to small absolute values of Mulliken charges. The transient absorption spectrum measured in the (*)OH radical reaction with all the indole chalcone derivatives exhibited a maximum at 390 nm, which is in excellent agreement with the computed value (394 nm). The formation of three phenolic products under steady-state radiolysis is in line with the three stable (*)OH adducts predicted by theory. Independent of the substituent, identical spectra (lambda(max) = 330-360 and approximately 580 nm) were obtained on one-electron oxidation of the three indole chalcones. MO calculations predict the deprotonation from the -NH group is more efficient than from the substituent due to the larger electron density on the N1 atom forming the chalcone indolyl radical. Its reduction potential was determined to be 0.56 V from the ABTS(*-)/ABTS(2-) couple. In benzenoid chalcones, the (*)OH adduct spectrum is characterized by a peak at 270 nm and a broad maximum centered in the range 430-450 nm with an intense bleaching at 340 nm. The spectrum formed by electron transfer in these derivatives with lambda(max) = 280 and 380 nm (epsilon(280) = 5000 dm(3) mol(-1) cm(-1) and epsilon(380) = 700 dm(3) mol(-1) cm(-1)) was assigned to its phenoxyl radical. Our pulse radiolysis experiments in combination with quantum chemical calculations demonstrate that chalcones are efficient scavengers of damaging oxyl radicals.
Compact sub-kilohertz low-frequency quantum light source based on four-wave mixing in cesium vapor

NASA Astrophysics Data System (ADS)

Ma, Rong; Liu, Wei; Qin, Zhongzhong; Su, Xiaolong; Jia, Xiaojun; Zhang, Junxiang; Gao, Jiangrui

2018-03-01

Using a nondegenerate four-wave mixing (FWM) process based on a double-{\\Lambda} scheme in hot cesium vapor, we demonstrate a compact diode-laser-pumped quantum light source for the generation of quantum correlated twin beams with a maximum squeezing of 6.5 dB. The squeezing is observed at a Fourier frequency in the audio band down to 0.7 kHz which, to the best of our knowledge, is the first observation of sub-kilohertz intensity-difference squeezing in an atomic system so far. A phase-matching condition is also investigated in our system, which confirms the spatial-multi-mode characteristics of the FWM process. Our compact low-frequency squeezed light source may find applications in quantum imaging, quantum metrology, and the transfer of optical squeezing onto a matter wave.

[Light response characteristics of photosynthesis and model comparison of Distylium chinense in different flooding durations].

PubMed

Liu, Ze-bin; Cheng, Rui-mei; Xiao, Wen-fa; Guo, Quan-shui; Wang, Na

2015-04-01

The light responses of photosynthesis of two-year-old Distytum chinense seedlings subjected to a simulated reservoir flooding environment in autumn and winter seasons were measured by using a Li-6400 XT portable photosynthesis system, and the light response curves were fitted and analyzed by three models of the rectangular hyperbola, non-rectangular hyperbola and modified rectangular hyperbola to investigate the applicability of different light response models for the D. chinense in different flooding durations and the adaption regulation of light response parameters to flooding stress. The results showed that the fitting effect of the non-rectangular hyperbola model for light response process of D. chinense under normal growth condition and under short-term flooding (15 days of flooding) was better than that of the other two models, while the fitting effect of the modified rectangular hyperbola model for light response process of D. chinense under longer-term flooding (30, 45 and 60 days of flooding) was better than that of the other two models. The modified rectangular hyperbola model gave the best fitted results of light compensation point (LCP) , maximum net photosynthetic rate (P(n max)) and light saturation point (LSP), and the non-rectangular hyperbola model gave the best fitted result of dark respiration rate (R(d)). The apparent quantum yield (Φ), P(n max) and LSP of D. chinense gradually decreased, and the LCP and R(d) of D. chinense gradually increased in early flooding (30 days), but D. chinense gradually produced adaptability for flooding as the flooding duration continued to increase, and various physiological indexes were gradually stabilized. Thus, this species has adaptability to some degree to the flooding environment.
Leaf Morphology, Photosynthetic Performance, Chlorophyll Fluorescence, Stomatal Development of Lettuce (Lactuca sativa L.) Exposed to Different Ratios of Red Light to Blue Light.

PubMed

Wang, Jun; Lu, Wei; Tong, Yuxin; Yang, Qichang

2016-01-01

Red and blue light are both vital factors for plant growth and development. We examined how different ratios of red light to blue light (R/B) provided by light-emitting diodes affected photosynthetic performance by investigating parameters related to photosynthesis, including leaf morphology, photosynthetic rate, chlorophyll fluorescence, stomatal development, light response curve, and nitrogen content. In this study, lettuce plants (Lactuca sativa L.) were exposed to 200 μmol⋅m(-2)⋅s(-1) irradiance for a 16 h⋅d(-1) photoperiod under the following six treatments: monochromatic red light (R), monochromatic blue light (B) and the mixture of R and B with different R/B ratios of 12, 8, 4, and 1. Leaf photosynthetic capacity (A max) and photosynthetic rate (P n) increased with decreasing R/B ratio until 1, associated with increased stomatal conductance, along with significant increase in stomatal density and slight decrease in stomatal size. P n and A max under B treatment had 7.6 and 11.8% reduction in comparison with those under R/B = 1 treatment, respectively. The effective quantum yield of PSII and the efficiency of excitation captured by open PSII center were also significantly lower under B treatment than those under the other treatments. However, shoot dry weight increased with increasing R/B ratio with the greatest value under R/B = 12 treatment. The increase of shoot dry weight was mainly caused by increasing leaf area and leaf number, but no significant difference was observed between R and R/B = 12 treatments. Based on the above results, we conclude that quantitative B could promote photosynthetic performance or growth by stimulating morphological and physiological responses, yet there was no positive correlation between P n and shoot dry weight accumulation.
Determination of unique power conversion efficiency of solar cell showing hysteresis in the I-V curve under various light intensities.

PubMed

Cojocaru, Ludmila; Uchida, Satoshi; Tamaki, Koichi; Jayaweera, Piyankarage V V; Kaneko, Shoji; Nakazaki, Jotaro; Kubo, Takaya; Segawa, Hiroshi

2017-09-18

Energy harvesting at low light intensities has recently attracted a great deal of attention of perovskite solar cells (PSCs) which are regarded as promising candidate for indoor application. Anomalous hysteresis of the PSCs a complex issue for reliable evaluation of the cell performance. In order to address these challenges, we constructed two new evaluation methods to determinate the power conversion efficiencies (PCEs) of PSCs. The first setup is a solar simulator based on light emitting diodes (LEDs) allowing evaluation of the solar cells at wider range of light intensities, ranging from 10 2 to 10 -3 mW·cm -2 . As the overestimate error, we found that the PCEs of dye sensitized solar cell (DSC) and PSCs increase dramatically at low light intensities conditions. Due to the internal capacitance at the interfaces on hybrid solar cells, the measurement of current below 10 -2 mW·cm -2 shows constant value given high PCE, which is related to the capacitive current and origin of the hysteresis. The second setup is a photovoltaic power analyzing system, designed for tracking the maximum power (P max ) with time. The paper suggests the combination of the LED solar simulator and P max tracking technique as a standard to evaluate the PCE of capacitive solar cells.
Polarized edge emission from GaN-based light-emitting diodes sandwiched by dielectric/metal hybrid reflectors

NASA Astrophysics Data System (ADS)

Yan, L. J.; Sheu, J. K.; Huang, F. W.; Lee, M. L.

2010-12-01

Edge-emitting c-plane GaN/sapphire-based light-emitting diodes (LEDs) sandwiched by two dielectric/metal hybrid reflectors on both sapphire and GaN surfaces were studied to determine their light emission polarization. The hybrid reflectors comprised dielectric multiple thin films and a metal layer. The metal layers of Au or Ag used in this study were designed to enhance the polarization ratio from S-polarization (transverse electric wave, TE) to P-polarization (transverse magnetic wave, TM). The two sets of optimized dielectric multi thin films served as matching layers for wide-angle incident light on both sapphire and GaN surfaces. To determine which reflector scheme would achieve a higher polarization ratio, simulations of the reflectance at the hybrid reflectors on sapphire (or GaN) interface were performed before the fabrication of experimental LEDs. Compared with conventional c-plane InGaN/GaN/sapphire LEDs without dielectric/metal hybrid reflectors, the experimental LEDs exhibited higher polarization ratio (ITE-max/ITM-max) with r=2.174 (˜3.37 dB) at a wavelength of 460 nm. In contrast, the original polarized light (without dielectric/metal hybrid reflectors) was partially contributed (r=1.398) by C-HH or C-LH (C band to the heavy-hole sub-band or C band to the crystal-field split-off sub-band) transitions along the a-plane or m-plane direction.
Characterization of arylalkylamine N-acetyltransferase (AANAT) activities and action spectrum for suppression in the band-legged cricket, Dianemobius nigrofasciatus (Orthoptera: Gryllidae).

PubMed

Izawa, Norimitsu; Suzuki, Takeshi; Watanabe, Masakatsu; Takeda, Makio

2009-04-01

Arylalkylamine N-acetyltransferase (AANAT), constituting a large family of enzymes, catalyzes the transacetylation from acetyl-CoA to monoamine substrates, although homology among species is not very high. AANAT in vertebrates is photosensitive and mediates circadian regulation. Here, we analyzed AANAT of the cricket, Dianemobius nigrofasciatus. The central nervous system contained AANAT activity. The optimum pHs were 6.0 (a minor peak) and 10.5 (a major peak) with crude enzyme solution. We analyzed the kinetics at pH 10.5 using the sample containing collective AANAT activities, which we term AANAT. Lineweaver-Burk plot and secondary plot yielded a K(m) for tryptamine as substrate of 0.42 microM, and a V(max) of 9.39 nmol/mg protein/min. The apparent K(m) for acetyl-CoA was 59.9 microM and the V(max) was 8.14 nmol/mg protein/min. AANAT of D. nigrofasciatus was light-sensitive. The activity was higher at night-time than at day-time as in vertebrates. To investigate most effective wavelengths on AANAT activity, a series of monochromatic lights was applied (350, 400, 450, 500, 550, 600 and 650 nm). AANAT showed the highest sensitivity to around 450 nm and 550 nm. 450 nm light was more effective than 550 nm light. Therefore, the most effective light affecting AANAT activity is blue light, which corresponds to the absorption spectrum of blue wave (BW)-opsin.
Anomalous pH Effect of Blue Proteorhodopsin.

PubMed

Yamada, Keisuke; Kawanabe, Akira; Yoshizawa, Susumu; Inoue, Kentaro; Kogure, Kazuhiro; Kandori, Hideki

2012-04-05

Proteorhodopsin (PR) is a light-driven proton pump found in marine bacteria, and thousands of PRs are classified into blue-absorbing PR (B-PR; λmax ≈ 490 nm) and green-absorbing PR (G-PR; λmax ≈ 525 nm). In this report, we present conversion of B-PR into G-PR using anomalous pH effect. B-PR in LC1-200, marine γ-proteobacteria, absorbs 497 and 513 nm maximally at pH 7 and 4, respectively, whose pH titration was reversible (pKa = 4.8). When pH was lowered from 4, the λmax was further red-shifted (528 nm at pH 2). This is unusual because blue shift occurs by chloride binding in the case of bacteriorhodopsin. Surprisingly, when pH was increased from 2 to 7, the λmax of this B-PR was further red-shifted to 540 nm, indicating that green-absorbing PR (PR540) is created only by changing pH. The present study reports the conformational flexibility of microbial rhodopsins, leading to the switch of absorbing color by a simple pH change.
Towards dropout training for convolutional neural networks.

PubMed

Wu, Haibing; Gu, Xiaodong

2015-11-01

Recently, dropout has seen increasing use in deep learning. For deep convolutional neural networks, dropout is known to work well in fully-connected layers. However, its effect in convolutional and pooling layers is still not clear. This paper demonstrates that max-pooling dropout is equivalent to randomly picking activation based on a multinomial distribution at training time. In light of this insight, we advocate employing our proposed probabilistic weighted pooling, instead of commonly used max-pooling, to act as model averaging at test time. Empirical evidence validates the superiority of probabilistic weighted pooling. We also empirically show that the effect of convolutional dropout is not trivial, despite the dramatically reduced possibility of over-fitting due to the convolutional architecture. Elaborately designing dropout training simultaneously in max-pooling and fully-connected layers, we achieve state-of-the-art performance on MNIST, and very competitive results on CIFAR-10 and CIFAR-100, relative to other approaches without data augmentation. Finally, we compare max-pooling dropout and stochastic pooling, both of which introduce stochasticity based on multinomial distributions at pooling stage. Copyright © 2015 Elsevier Ltd. All rights reserved.
Physcomitrella patens MAX2 characterization suggests an ancient role for this F-box protein in photomorphogenesis rather than strigolactone signalling.

PubMed

Lopez-Obando, Mauricio; de Villiers, Ruan; Hoffmann, Beate; Ma, Linnan; de Saint Germain, Alexandre; Kossmann, Jens; Coudert, Yoan; Harrison, C Jill; Rameau, Catherine; Hills, Paul; Bonhomme, Sandrine

2018-05-21

Strigolactones (SLs) are key hormonal regulators of flowering plant development and are widely distributed amongst streptophytes. In Arabidopsis, SLs signal via the F-box protein MORE AXILLARY GROWTH2 (MAX2), affecting multiple aspects of development including shoot branching, root architecture and drought tolerance. Previous characterization of a Physcomitrella patens moss mutant with defective SL synthesis supports an ancient role for SLs in land plants, but the origin and evolution of signalling pathway components are unknown. Here we investigate the function of a moss homologue of MAX2, PpMAX2, and characterize its role in SL signalling pathway evolution by genetic analysis. We report that the moss Ppmax2 mutant shows very distinct phenotypes from the moss SL-deficient mutant. In addition, the Ppmax2 mutant remains sensitive to SLs, showing a clear transcriptional SL response in dark conditions, and the response to red light is also altered. These data suggest divergent evolutionary trajectories for SL signalling pathway evolution in mosses and vascular plants. In P. patens, the primary roles for MAX2 are in photomorphogenesis and moss early development rather than in SL response, which may require other, as yet unidentified, factors. © 2018 INRA New Phytologist © 2018 New Phytologist Trust.
CRITICAL DIFFERENCES AND CLUES IN ETA CAR'S 2009 EVENT ,

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

Mehner, Andrea; Davidson, Kris; Humphreys, Roberta M.

2011-10-20

We monitored Eta Carinae with the Hubble Space Telescope WFPC2 and Gemini GMOS throughout the 2009 spectroscopic event, which was expected to differ from its predecessor in 2003. Here we report major observed differences between events and their implications. Some of these results were quite unexpected. (1) The UV brightness minimum was much deeper in 2009. This suggests that physical conditions in the early stages of an event depend on different parameters than the 'normal' inter-event wind. Extra mass ejection from the primary star is one possible cause. (2) The expected He II {lambda}4687 brightness maximum was followed several weeksmore » later by another. We explain why this fact and the timing of the {lambda}4687 maxima strongly support a 'shock breakup' hypothesis for X-ray and {lambda}4687 behavior as proposed 5-10 years ago. (3) We observed a polar view of the star via light reflected by dust in the Homunculus nebula. Surprisingly, at that location, the variations of emission-line brightness and Doppler velocities closely resembled a direct view of the star, which should not have been true for any phenomena related to the orbit. This result casts very serious doubt on all the proposed velocity interpretations that depend on the secondary star's orbital motion. (4) Latitude-dependent variations of H I, He I, and Fe II features reveal aspects of wind behavior during the event. In addition, we discuss implications of the observations for several crucial unsolved problems.« less
Autofluorescence spectroscopy of oral mucosa

NASA Astrophysics Data System (ADS)

Majumdar, S. K.; Uppal, A.; Gupta, P. K.

1998-06-01

We report the results of an in-vitro study on autofluorescence from pathologically characterized normal and malignant squamous tissues from the oral cavity. The study involved biopsy samples from 47 patients with oral cancer of which 11 patients had cancer of tongue, 17 of buccal mucosa and 19 of alveolus. The results of excitation and emission spectroscopy at several wavelengths (280 nm less than or equal to (lambda) exless than or equal to 460 nm; 340 nm less than or equal to (lambda) em less than or equal to 520 nm) showed that at (lambda) ex equals 337 nm and 400 nm the mean value for the spectrally integrated fluorescence intensity [(Sigma) (lambda ) IF((lambda) )] from the normal tissue sites was about a factor of 2 larger than that from the malignant tissue sites. At other excitation wavelengths the difference in (Sigma) (lambda ) IF((lambda) ) was not statistically significant. Similarly, for (lambda) em equals 390 nm and 460 nm, the intensity of the 340 nm band of the excitation spectra from normal tissues was observed to be a factor of 2 larger than that from malignant tissues. Analysis of these results suggests that NADH concentration is higher in normal oral tissues compared to the malignant. This contrasts with our earlier observation of an reduced NADH concentration in normal sites of breast tissues vis a vis malignant sites. For the 337 nm excited emission spectra a 10-variable MVLR score (using (Sigma) (lambda ) IF((lambda) ) and normalized intensities at nine wavelengths as input parameters) provided a sensitivity and specificity of 95.7% and 93.1% over the sample size investigated.
Biological trait analysis and stability of lambda-cyhalothrin resistance in the house fly, Musca domestica L. (Diptera: Muscidae).

PubMed

Abbas, Naeem; Shah, Rizwan Mustafa; Shad, Sarfraz Ali; Iqbal, Naeem; Razaq, Muhammad

2016-05-01

House flies, Musca domestica L., (Diptera: Muscidae), are pests of poultry and have the ability to develop resistance to insecticides. To design a strategy for resistance management, life history traits based on laboratory observations were established for lambda-cyhalothrin-resistant, susceptible and reciprocal crosses of M. domestica strains. Bioassay results showed that the lambda-cyhalothrin-selected strain developed a resistance ratio of 98.34 compared to its susceptible strain. The lambda-cyhalothrin-selected strain had a relative fitness of 0.26 and lower fecundity, hatchability, lower number of next generation larvae, and net reproductive rate compared with its susceptible strain. Mean population growth rates, such as intrinsic rate of population increase, and biotic potential were lower for the lambda-cyhalothrin-selected strain compared to its susceptible strain. Resistance to lambda-cyhalothrin, indoxacarb, and abamectin was unstable while resistance to bifenthrin and methomyl was stable in the lambda-cyhalothrin-selected strain of M. domestica. Development of resistance can cost considerable fitness for the lambda-cyhalothrin-selected strain. The present study provided useful information for making potential management strategies to delay resistance development in M. domestica.
Depolymerized products of lambda-carrageenan as a potent angiogenesis inhibitor.

PubMed

Chen, Haimin; Yan, Xiaojun; Lin, Jing; Wang, Feng; Xu, Weifeng

2007-08-22

Since angiogenesis is involved in initiating and promoting several diseases such as cancer and cardiovascular events, this study was designed to evaluate the anti-angiogenesis of low-molecular-weight (LMW), highly sulfated lambda-carrageenan oligosaccharides (lambda-CO) obtained by carrageenan depolymerization, by CAM (chick chorioallantoic membrane) model and human umbilical vein endothelial cells (HUVECs). Significant inhibition of vessel growth was observed at 200 microg/pellet. A histochemistry assay also revealed a decrease of capillary plexus and connective tissue in lambda-CO treated samples. lambda-CO inhibited the viability of cells at the high concentration of 1 mg/mL, whereas it affected the cell survival slightly (>95%) at a low concentration (<250 microg/mL), and HUVEC is the most sensitive to lambda-CO among three kinds of cells. Furthermore, the inhibitory action of lambda-CO was also observed in the endothelial cell invasion and migration at relatively low concentration (150-300 microg/mL), through down-regulation of intracellular matrix metalloproteinases (MMP-2) expression on endothelial cells. Taken together, these findings demonstrate that lambda-CO is a potential angiogenesis inhibitor with combined effects of inhibiting invasion, migration, and proliferation.
Oxidative and apoptotic effects of lambda-cyhalothrin modulated by piperonyl butoxide in the liver of Oreochromis niloticus.

PubMed

Piner, Petek; Uner, Nevin

2012-05-01

The aim of this study was to investigate the toxic effects of pyrethroid pesticide lambda-cyhalothrin in the presence of piperonyl butoxide as a modulator in the liver of juvenile Oreochromis niloticus. LC(50) (96h) value of lambda-cyhalothrin was determined as 2.901μg/L for O. niloticus. The fish were exposed to 0.48μg/L (1/6 of the 96-h LC(50)) lambda-cyhalothrin and 10μg/L piperonyl butoxide for 96-h and 15-d. tGSH, GSH, GSSG, Hsp70 and TBARS contents, GPx, GR, GST and caspase-3 enzymes activities were determined. Lambda-cyhalothrin caused increases in tGSH, GSH, TBARS contents, and GST activity. Piperonyl butoxide treatment with lambda-cyhalothrin caused significant increases in tGSH GSH, Hsp70, TBARS contents, and GPx and GST activities while caspase-3 activity was decreased. The results of the present study revealed that lambda-cyhalothrin caused oxidative stress which upregulated GSH and GSH-related enzymes. Piperonyl butoxide increased the oxidative stress potential and apoptotic effects of lambda-cyhalothrin. Copyright Â© 2012 Elsevier B.V. All rights reserved.
IUE and Einstein observations of the LINER galaxy NGC 4579

NASA Technical Reports Server (NTRS)

Reichert, G. A.; Puchnarewicz, E. M.; Mason, K. O.

1990-01-01

Results of International Ultraviolet Explorer (IUE) and Einstein observations of the LINER galaxy NGC 4579 are reported. Spatial profiles of the long wavelength IUE emission show a two component structure, with an unresolved core superimposed on broader underlying emission. The core spectrum shows strong C II lambda 2326 and broad Mg II lambda 2800 emission, and perhaps emission due to blends of Fe II multiplets (2300 to 23600 angstrom). The short wavelength emission is spatially unresolved, and shows C II lambda 1335, C III lambda 1909 broad C IV lambda 1550 emission, and a broad feature at approximately 1360 angstrom which may be due to 0.1 lambda 1356. Contrary to previous reports no evidence for He II lambda 1640 is found in the spectrum. An unresolved x ray source is detected at the location of the nucleus; its spectrum is well fitted by a power law of energy slope alpha approximately -0.5. These results further support the idea that NGC 4579 may contain a dwarf Seyfert nucleus.
Segregated tandem filter for enhanced conversion efficiency in a thermophotovoltaic energy conversion system

DOEpatents

Brown, Edward J.; Baldasaro, Paul F.; Dziendziel, Randolph J.

1997-01-01

A filter system to transmit short wavelength radiation and reflect long wavelength radiation for a thermophotovoltaic energy conversion cell comprises an optically transparent substrate segregation layer with at least one coherent wavelength in optical thickness; a dielectric interference filter deposited on one side of the substrate segregation layer, the interference filter being disposed toward the source of radiation, the interference filter including a plurality of alternating layers of high and low optical index materials adapted to change from transmitting to reflecting at a nominal wavelength .lambda..sub.IF approximately equal to the bandgap wavelength .lambda..sub.g of the thermophotovoltaic cell, the interference filter being adapted to transmit incident radiation from about 0.5.lambda..sub.IF to .lambda..sub.IF and reflect from .lambda..sub.IF to about 2.lambda..sub.IF ; and a high mobility plasma filter deposited on the opposite side of the substrate segregation layer, the plasma filter being adapted to start to become reflecting at a wavelength of about 1.5.lambda..sub.IF.
[In vitro anti-angiogenic action of lambda-carrageenan oligosaccharides].

PubMed

Chen, Hai-Min; Yan, Xiao-Jun; Wang, Feng; Lin, Jing; Xu, Wei-Feng

2007-06-01

This study was designed to evaluate the inhibition effect of lambda-carrageenan oligosaccharides on neovascularization in vitro by chick chorioallantoic membrane (CAM) model and human umbilical vein endothelial cell ( HUVEC). lambda-Carrageenan oligosaccharides caused a dose-dependent decrease of the vascular density of CAM, and adversely affected capillary plexus formation. At a high concentration of 1 mg x mL(-1), this compound inhibited the endothelial cell proliferation, while low concentration of lambda-carrageenan oligosaccharides (< 250 microg x mL(-1)) affected the cell survival slightly (> 95%). Different cytotoxic sensitivity of lambda-carrageenan oligosaccharides in three kinds of cells was observed, of which HUVEC is the most sensitive to this oligosaccharides. The inhibitory action of lambda-carrageenan oligosaccharides on the endothelial cell invasion and migration was also observed at relatively low concentration (150 - 300 microg x mL(-1)) through down-regulation of intracellular matrix metalloproteinases-2 (MMP-2) expression on endothelial cells. Current observations demonstrated that lambda-carrageenan oligosaccharides are potential angiogenesis inhibitor with combined effects of inhibiting invasion, migration and proliferation.
Effect of atmospheric extinction on laser rangefinder performance at 1.54 and 0.6 microns

NASA Technical Reports Server (NTRS)

Hutt, D. L.; Theriault, J.-M.; Larochelle, V.; Bonnier, D.

1992-01-01

Extinction of laser rangefinder (LRF) pulses by the atmosphere depends on the wavelength, weather conditions, and aerosol concentration along the optical path. In the IR, extinction is due to absorption by molecular constituents and scattering and absorption by aerosols. The total atmospheric extinction alpha(lambda) is the sum of the molecular and aerosol contributions, alpha(sub m)(lambda)and Alpha(sub a)(lambda). We present simple expressions for alpha(sub m)(lambda) and alpha(sub a)(lambda) for two LRF sources: Er:glass and CO2 which operate at 1.54 and 10.6 microns, respectively. The expressions are based on accepted models of atmospheric aerosols and molecular extinction and give an estimate of alpha(lambda) as a function of standard meteorological parameters, assuming horizontal beam propagation. Signal-to-noise ratios of LRF returns, measured from a reference target under different weather conditions are compared to predictions based on the estimate of alpha(lambda).
On Spectral Invariance of Single Scattering Albedo for Water Droplets and Ice Crystals at Weakly Absorbing Wavelengths

NASA Technical Reports Server (NTRS)

Marshak, Alexander; Knyazikhin, Yuri; Chiu, J. Christine; Wiscombe, Warren J.

2012-01-01

The single scattering albedo omega(sub O lambda) in atmospheric radiative transfer is the ratio of the scattering coefficient to the extinction coefficient. For cloud water droplets both the scattering and absorption coefficients, thus the single scattering albedo, are functions of wavelength lambda and droplet size r. This note shows that for water droplets at weakly absorbing wavelengths, the ratio omega(sub O lambda)(r)/omega(sub O lambda)(r (sub O)) of two single scattering albedo spectra is a linear function of omega(sub O lambda)(r). The slope and intercept of the linear function are wavelength independent and sum to unity. This relationship allows for a representation of any single scattering albedo spectrum omega(sub O lambda)(r) via one known spectrum omega(sub O lambda)(r (sub O)). We provide a simple physical explanation of the discovered relationship. Similar linear relationships were found for the single scattering albedo spectra of non-spherical ice crystals.
Duality symmetry and power-law fading of frustration in a quantum multiconnected superconductor

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

Sun, S.N.; Ralston, J.P.

1991-03-01

We generalize the Alexander--de Gennes equations to a new system of superconducting-wire networks, allowing for variation of the cross-sectional area of wires. The generalized equations are solved for a square lattice of different cross-sectional-area ratios {lambda} in the {ital x} and {ital y} directions. A symmetry of {lambda}{r arrow}1/{lambda} is related to the Aubry-Andre duality and an obvious geometric property. We find that even a slight geometric asymmetry can soften the fine structure of the magnetic phase boundary considerably. We obtain a power-law dependence on the parameter {lambda} as {lambda}{r arrow}{infinity} and {lambda}{r arrow}0. For a finite-area ratio {lambda}, wemore » speculate that a simple analytic fit incorporating the dual symmetry is close to the exact nonperturbative behavior. The system is also related analytically to a recent study of Hu and Chen, which revealed a power-law behavior for a rectangular lattice.« less
Structural basis of light chain amyloidogenicity: comparison of the thermodynamic properties, fibrillogenic potential and tertiary structural features of four vλ6 proteins

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

Wall, J.S.; Gupta, V.; Wilkerson, M.

2004-04-01

Primary (AL) amyloidosis results from the pathologic deposition of monoclonal light chains as amyloid fibrils. Studies of recombinant-derived variable region (V{sub L}) fragments of these proteins have shown an inverse relationship between thermodynamic stability and fibrillogenic potential. Further, ionic interactions within the V{sub L} domain were predicted to influence the kinetics of light chain fibrillogenicity, as evidenced from our analyses of a relatively stable V{sub {lambda}}6 protein (Jto) with a long range electrostatic interaction between Asp and Arg side chains at position 29 and 68, respectively, and an unstable, highly fibrillogenic V{sub {lambda}}6 protein (Wil) that had neutral amino acidsmore » at these locations. To test this hypothesis, we have generated two Jto-related mutants designed to disrupt the interaction between Asp 29 and Arg 68 (JtoD29A and JtoR68S). Although the thermodynamic stabilities of unfolding for these two molecules were identical, they exhibited very different kinetics of fibril formation: the rate of JtoD29A fibrillogenesis was slow and comparable to the parent molecule, whereas that of JtoR68S was significantly faster. High-resolution X-ray diffraction analyses of crystals prepared from the two mutants having the same space group and unit cell dimensions revealed no significant main-chain conformational changes. However, several notable side-chain alterations were observed in JtoR68S, as compared with JtoD29A, that resulted in the solvent exposure of a greater hydrophobic surface and modifications in the electrostatic potential surface. We posit that these differences contributed to the enhanced fibrillogenic potential of the Arg 68 mutant, since both Jto mutants lacked the intrachain ionic interaction and were equivalently unstable. The information gleaned from our studies has provided insight into structural parameters that in addition to overall thermodynamic stability, contribute to the fibril forming propensity of immunoglobulin light chains.« less

Are non-linearity effects of absorption important for MAX-DOAS observations?

NASA Astrophysics Data System (ADS)

Pukite, Janis; Wang, Yang; Wagner, Thomas

2017-04-01

For scattered light observations the absorption optical depth depends non-linearly on the trace gas concentrations if their absorption is strong. This is the case because the Beer-Lambert law is generally not applicable for scattered light measurements due to many (i.e. more than one) light paths contributing to the measurement. While in many cases a linear approximation can be made, for scenarios with strong absorption non-linear effects cannot always be neglected. This is especially the case for observation geometries with spatially extended and diffuse light paths, especially in satellite limb geometry but also for nadir measurements as well. Fortunately the effects of non-linear effects can be quantified by means of expanding the radiative transfer equation in a Taylor series with respect to the trace gas absorption coefficients. Herewith if necessary (1) the higher order absorption structures can be described as separate fit parameters in the DOAS fit and (2) the algorithm constraints of retrievals of VCDs and profiles can be improved by considering higher order sensitivity parameters. In this study we investigate the contribution of the higher order absorption structures for MAX-DOAS observation geometry for different atmospheric and ground properties (cloud and aerosol effects, trace gas amount, albedo) and geometry (different Sun and viewing angles).
Further improvements of a new model for turbulent convection in stars

NASA Technical Reports Server (NTRS)

Canuto, V. M.; Mazzitelli, I.

1992-01-01

The effects of including a variable molecular weight and of using the newest opacities of Rogers and Iglesias (1991) as inputs to a recent model by Canuto and Mazzitelli (1991) for stellar turbulent convection are studied. Solar evolutionary tracks are used to conclude that the the original model for turbulence with mixing length Lambda = z, Giuli's variable Q unequal to 1 and the new opacities yields a fit to solar T(eff) within 0.5 percent. A formulation of Lambda is proposed that extends the purely nonlocal Lambda = z expression to include local effects. A new expression for Lambda is obtained which generalizes both the mixing length theory (MLT) phenomenological expression for Lambda as well as the model Lambda = z. It is argued that the MLT should now be abandoned.
System Size and Energy Dependence on Strangeness Production in 22 GeV Cu+Cu Collisions at RHIC

DTIC Science & Technology

2011-05-10

relativistic speeds approaching the speed of light before they meet in an extremely high temperature collision. The Solenoidal Tracker at RHIC (STAR...extremely high energy and temperature. This project determines the yield of strange quarks through measurements of K0-short mesons as well as Lambda and Anti...charge. These quarks are never observed alone, but are observable in the form of baryons (3 quarks) or mesons (a quark-anti-quark pair). The
Near-infrared scintillation of liquid argon

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

Alexander, T.; Escobar, C. O.; Lippincott, W. H.

2016-03-03

Since the 1970s it has been known that noble gases scintillate in the near infrared (NIR) region of the spectrum (0.7more » $$\\mu$$m < $$\\lambda$$; < 1.5$$\\mu$$m). More controversial has been the question of the NIR light yield for condensed noble gases. We first present the motivation for using the NIR scintillation in liquid argon detectors, then briefly review early as well as more recent efforts and finally show encouraging preliminary results of a test performed at Fermilab.« less
Sensitized photooxidation of phenols by fulvic acid and in natural waters

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

Faust, B.C.; Hoigne, J.

1987-10-01

In addition to singlet oxygen, irradiation of fulvic acid solutions and lake water with UV and visible light (lambda > 315 nm) produces another transient oxidant species. This transient oxidant (probably an organic peroxy radical) is derived from natural dissolved organic material (DOM) and controls DOM-sensitized photooxidations of various alkylphenols. On the basis of kinetic data for the transient oxidant, DOM-sensitized photooxidation half-lives of alkylphenols are estimated to range from 1 day to several months in middle-latitude shallow surface waters.
A new small-angle X-ray scattering set-up on the crystallography beamline I711 at MAX-lab.

PubMed

Knaapila, M; Svensson, C; Barauskas, J; Zackrisson, M; Nielsen, S S; Toft, K N; Vestergaard, B; Arleth, L; Olsson, U; Pedersen, J S; Cerenius, Y

2009-07-01

A small-angle X-ray scattering (SAXS) set-up has recently been developed at beamline I711 at the MAX II storage ring in Lund (Sweden). An overview of the required modifications is presented here together with a number of application examples. The accessible q range in a SAXS experiment is 0.009-0.3 A(-1) for the standard set-up but depends on the sample-to-detector distance, detector offset, beamstop size and wavelength. The SAXS camera has been designed to have a low background and has three collinear slit sets for collimating the incident beam. The standard beam size is about 0.37 mm x 0.37 mm (full width at half-maximum) at the sample position, with a flux of 4 x 10(10) photons s(-1) and lambda = 1.1 A. The vacuum is of the order of 0.05 mbar in the unbroken beam path from the first slits until the exit window in front of the detector. A large sample chamber with a number of lead-throughs allows different sample environments to be mounted. This station is used for measurements on weakly scattering proteins in solutions and also for colloids, polymers and other nanoscale structures. A special application supported by the beamline is the effort to establish a micro-fluidic sample environment for structural analysis of samples that are only available in limited quantities. Overall, this work demonstrates how a cost-effective SAXS station can be constructed on a multipurpose beamline.
Total enantioselectivity in the DNA binding of the dinuclear ruthenium(II) complex [[Ru(Me2bpy)2]2(mu-bpm)]4+ [bpm = 2,2'-bipyrimidine; Me2bpy = 4,4'-dimethyl-2,2'-bipyridine].

PubMed

Smith, Jayden A; Collins, J Grant; Patterson, Bradley T; Keene, F Richard

2004-05-07

The binding of the three stereoisomers (DeltaDelta-, LambdaLambda- and DeltaLambda-) of the dinuclear ruthenium(II) complex [[Ru(Me2bpy)2]2(mu-bpm)]4+ [Me2bpy = 4,4'-dimethyl-2,2'-bipyridine; bpm = 2,2'-bipyrimidine] to a tridecanucleotide containing a single adenine bulge has been studied by 1H NMR spectroscopy. The addition of the DeltaDelta-isomer to d(CCGAGAATTCCGG)2 induced significant chemical shift changes for the base and sugar resonances of the residues at the bulge site (G3A4G5/C11C10), whereas small shifts were observed upon addition of the enantiomeric LambdaLambda-form. NOESY spectra of the tridecanucleotide bound with the DeltaDelta-isomer revealed intermolecular NOE's between the metal complex and the nucleotide residues at the bulge site, while only weak NOE's were observed to terminal residues to the LambdaLambda-form. Competitive binding studies were performed where both enantiomers were simultaneously added to the tridecanucleotide, and for all ratios of the two stereoisomers the DeltaDelta-isomer remained selectively bound at the bulge site with the LambdaLambda-enantiomer localised at the terminal regions of the tridecanucleotide. The meso-diastereoisomer (DeltaLambda) was found to bind to the tridecanucleotide with characteristics intermediate between the DeltaDelta- and LambdaLambda-enantiomers of the rac form. Two distinct sets of metal complex resonances were observed, with one set having essentially the same shift as the free metal complex, whilst the other set of resonances exhibited significant shifts. The NOE data indicated that the meso-diastereoisomer does not bind as selectively as the DeltaDelta-isomer, with NOE's observed to a greater number of nucleotide residues compared to the DeltaDelta-form. This study provides a rare example of total enantioselectivity in the binding of an inert transition metal complex to DNA, produced by the shape recognition of both ruthenium(II) centres.
FAR-ULTRAVIOLET SPECTRAL IMAGES OF THE VELA SUPERNOVA REMNANT: SUPPLEMENTS AND COMPARISONS WITH OTHER WAVELENGTH IMAGES

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

Kim, Il-Joong; Seon, Kwang-Il; Han, Wonyong

We present the improved far-ultraviolet (FUV) emission-line images of the entire Vela supernova remnant (SNR) using newly processed Spectroscopy of Plasma Evolution from Astrophysical Radiation/Far-Ultraviolet Imaging Spectrograph (SPEAR/FIMS) data. The incomplete C III {lambda}977 and O VI {lambda}{lambda}1032, 1038 images presented in the previous study are updated to cover the whole region. The C IV {lambda}{lambda}1548, 1551 image with a higher resolution and new images at Si IV {lambda}{lambda}1394, 1403, O IV] {lambda}1404, He II {lambda}1640.5, and O III] {lambda}{lambda}1661, 1666 are also shown. Comparison of emission-line ratios for two enhanced FUV regions reveals that the FUV emissions of themore » east-enhanced FUV region may be affected by nonradiative shocks of another very young SNR, the Vela Jr. SNR (RX J0852.0-4622, G266.6-1.2). This result is the first FUV detection that is likely associated with the Vela Jr. SNR, supporting previous arguments that the Vela Jr. SNR is close to us. The comparison of the improved FUV images with soft X-ray images shows that an FUV filamentary feature forms the boundary of the northeast-southwest asymmetrical sections of the X-ray shell. The southwest FUV features are characterized as the region where the Vela SNR is interacting with slightly denser ambient medium within the dim X-ray southwest section. From a comparison with the H{alpha} image, we identify a ring-like H{alpha} feature overlapped with an extended hot X-ray feature of similar size and two local peaks of C IV emission. Their morphologies are expected when the H{alpha} ring is in direct contact with the near or far side of the Vela SNR.« less
Preparing the MAX IV storage rings for timing-based experiments

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

Stråhlman, C., E-mail: Christian.Strahlman@maxlab.lu.se; Olsson, T., E-mail: Teresia.Olsson@maxlab.lu.se; Leemann, S. C.

2016-07-27

Time-resolved experimental techniques are increasingly abundant at storage ring facilities. Recent developments in accelerator technology and beamline instrumentation allow for simultaneous operation of high-intensity and timing-based experiments. The MAX IV facility is a state-of-the-art synchrotron light source in Lund, Sweden, that will come into operation in 2016. As many storage ring facilities are pursuing upgrade programs employing strong-focusing multibend achromats and passive harmonic cavities (HCs) in high-current operation, it is of broad interest to study the accelerator and instrumentation developments required to enable timing-based experiments at such machines. In particular, the use of hybrid filling modes combined with pulse pickingmore » by resonant excitation or pseudo single bunch has shown promising results. These methods can be combined with novel beamline instrumentation, such as choppers and instrument gating. In this paper we discuss how these techniques can be implemented and employed at MAX IV.« less
Limits on the Decay-Rate Difference of Neutral-B Mesons and on CP, T, and CPT Violation in B0-antiB0 Oscillations

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

Aubert, B

2004-02-29

Using events in which one of two neutral-B mesons from the decay of an {Upsilon}(4S) resonance is fully reconstructed, we set limits on the difference between the decay rates of the two neutral-B mass eigenstates and on CP, T, and CPT violation in B{sup 0}{bar B}{sup 0} mixing. The reconstructed decays, comprising both CP and flavor eigenstates, are obtained from 88 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We determine six independent parameters governing oscillations ({Delta}m, {Delta}{Lambda}/{Lambda}), CPT and CP violation (Re z, Im z), and CP andmore » T violation (Im {lambda}{sub CP}, |q/p|), where {lambda}{sub cp} characterizes B{sup 0} and {bar B}{sup 0} decays to states of charmonium plus K{sub S}{sup 0} or K{sub L}{sup 0}. The results are sgn(Re {lambda}{sub CP}){Delta}{Lambda}/{Lambda} = .0.008 {+-} 0.037(stat.) {+-} 0.018(syst.) [-0.084, 0.068], |q/p| = 1.029 {+-} 0.013(stat.) {+-} 0.011(syst.) [1.001, 1.057], (Re {lambda}{sub CP}/|{lambda}{sub CP}|)Re z = 0.014 {+-} 0.035(stat.) {+-} 0.034(syst.) [-0.072, 0.101], Imz = 0.038 {+-} 0.029(stat.) {+-} 0.025(syst.) [-0.028, 0.104]. The values inside square brackets indicate the 90% confidence-level intervals. The values of Im {lambda}{sub CP} and {Delta}m are consistent with previous analyses and are used as cross-checks. These measurements are in agreement with Standard Model expectations.« less
The study of correlation among different scattering parameters in an aggregate dust model

NASA Astrophysics Data System (ADS)

Mazarbhuiya, A. M.; Das, H. S.

2017-09-01

We study the light scattering properties of aggregate particles in a wide range of complex refractive indices (m = n + i k, where 1.4 ≤ n ≤ 2.0, 0.001 ≤ k ≤1.0) and wavelengths (0.45 ≤ λ≤1.25 μ m) to investigate the correlation among different parameters e.g., the positive polarization maximum (P_{max}), the amplitude of the negative polarization (P_{min}), geometric albedo (A), (n,k) and λ. Numerical computations are performed by the Superposition T-matrix code with Ballistic Cluster-Cluster Aggregate (BCCA) particles of 128 monomers and Ballistic Aggregates (BA) particles of 512 monomers, where monomer's radius of aggregates is considered to be 0.1 μm. At a fixed value of k, P_{max} and n are correlated via a quadratic regression equation and this nature is observed at all wavelengths. Further, P_{max} and k are found to be related via a polynomial regression equation when n is taken to be fixed. The degree of the equation depends on the wavelength, higher the wavelength lower is the degree. We find that A and P_{max} are correlated via a cubic regression at λ= 0.45 μ m whereas this correlation is quadratic at higher wavelengths. We notice that |P_{min}| increases with the decrease of P_{max} and a strong linear correlation between them is observed when n is fixed at some value and k is changed from higher to lower value. Further, at a fix value of k, P_{min} and P_{max} can be fitted well via a quartic regression equation when n is changed from higher to lower value. We also find that P_{max} increases with λ and they are correlated via a quartic regression.
Simple model for lambda-doublet propensities in bimolecular reactions

NASA Technical Reports Server (NTRS)

Bronikowski, Michael J.; Zare, Richard N.

1990-01-01

A simple geometric model is presented to account for lambda-doublet propensities in bimolecular reactions A + BC - AB + C. It applies to reactions in which AB is formed in a pi state, and in which the unpaired molecular orbital responsible for lambda-doubling arises from breaking the B-C bond. The lambda-doublet population ratio is predicted to be 2:1 provided that: (1) the motion of A in the transition state determines the plane of rotation of AB; (2) the unpaired pi orbital lying initially along the B-C bond may be resolved into a projection onto the AB plane of rotation and a projection perpendicular to this plane; (3) there is no preferred geometry for dissociation of ABC. The 2:1 lambda-doublet ratio is the 'unconstrained dynamics prior' lambda-doublet distribution for such reactions.
Effective screening length of isotropic liquid samples submitted to an applied voltage.

PubMed

Zola, R S; Evangelista, L R; Barbero, G

2006-05-25

A cell of isotropic liquid in the shape of a slab of thickness d and containing ionic impurities is considered. It is shown that the screening effect produced by the ionic charges on the external field is characterized by an effective surface length, lambda(S)(U), depending on the applied voltage U. The analysis indicates that lambda(S)(U)) < lambda(D) when the applied voltage is very large, and lambda(S)(U) --> lambda(D) for very small values of the applied voltage, where lambda(D) is the Debye screening length. The presence of the ions is responsible also for a counterpotential, v, that for small U is such to cancel the effective electric field in the sample, whereas in the opposite limit it is inversely proportional to the applied difference of potential.
The Legacy Archive for Microwave Background Data Analysis (LAMBDA)

NASA Astrophysics Data System (ADS)

Miller, Nathan; LAMBDA

2018-01-01

The Legacy Archive for Microwave Background Data Analysis (LAMBDA) provides CMB researchers with archival data for cosmology missions, software tools, and links to other sites of interest. LAMBDA is one-stop shopping for CMB researchers. It hosts data from WMAP along with many suborbital experiments. Over the past year, LAMBDA has acquired new data from SPTpol, SPIDER and ACTPol. In addition to the primary CMB, LAMBDA also provides foreground data.LAMBDA has several ongoing efforts to provide tools for CMB researchers. These tools include a web interface for CAMB and a web interface for a CMB survey footprint database and plotting tool. Additionally, we have recently developed a Docker container with standard CMB analysis tools and demonstrations in the form of Jupyter notebooks. These containers will be publically available through Docker's container repository and the source will be available on github.
Interferon lambda 1-3 expression in infants hospitalized for RSV or HRV associated bronchiolitis.

PubMed

Selvaggi, Carla; Pierangeli, Alessandra; Fabiani, Marco; Spano, Lucia; Nicolai, Ambra; Papoff, Paola; Moretti, Corrado; Midulla, Fabio; Antonelli, Guido; Scagnolari, Carolina

2014-05-01

The airway expression of type III interferons (IFNs) was evaluated in infants hospitalized for respiratory syncytial virus (RSV) or rhinovirus (HRV) bronchiolitis. As an additional objective we sought to determine whether a different expression of IFN lambda 1-3 was associated with different harboring viruses, the clinical course of bronchiolitis or with the levels of well established IFN stimulated genes (ISGs), such as mixovirus resistance A (MxA) and ISG56. The analysis was undertaken in 118 infants with RSV or HRV bronchiolitis. Nasopharyngeal washes were collected for virological studies and molecular analysis of type III IFN responses. RSV elicited higher levels of IFN lambda subtypes when compared with HRV. A similar expression of type III IFN was found in RSVA or RSVB infected infants and in those infected with HRVA or HRVC viruses. Results also indicate that IFN lambda 1 and IFN lambda 2-3 levels were correlated with each other and with MxA and ISG56-mRNAs. In addition, a positive correlation exists between the IFN lambda1 levels and the clinical score index during RSV infection. In particular, higher IFN lambda 1 levels are associated to an increase of respiratory rate. These findings show that differences in the IFN lambda 1-3 levels in infants with RSV or HRV infections are present and that the expression of IFN lambda 1 correlates with the severity of RSV bronchiolitis. Copyright © 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.
Risk assessment of lambda-cyhalothrin on aquatic organisms in paddy field in China.

PubMed

Gu, Bao G; Wang, Hui M; Chen, William L; Cai, Dao J; Shan, Zheng J

2007-06-01

This study was carried out to assess the risk of lambda-cyhalothrin to aquatic organisms used in paddy field, and to provide assistance in the ecological risk management of lambda-cyhalothrin. The acute toxicities of five individual formulations of lambda-cyhalothrin to four aquatic species were investigated in the laboratory, as well as in a simulated paddy field-pond ecosystem, and the results implicated that lambda-cyhalothrin is highly toxic to fish, and to a greater extent to shrimp. There were differences in the toxicities to each aquatic organisms among different formulations. lambda-Cyhalothrin degraded rapidly in the environment, with half-lives of different formulations in paddy field water (0.23-0.53 days), pond water (0.38-0.63 days), and paddy field soil (0.96-7.35 days), respectively. The water overflow from the paddy field following a simulated rainstorm 12h after application of lambda-cyhalothrin did not cause injury to fish, clam or crab, but was severely hazardous to shrimp. Additionally, no injury to shrimp was found when simulated overflow occurred 4 days after application. These results suggest that the environmental risk of lambda-cyhalothrin to aquatic organisms can be reduced by (1) developing a relatively safe formulation such as a suspension concentrate, and/or (2) controlling the drainage time of the paddy field.
Broadband Achromatic Phase Shifter for a Nulling Interferometer

NASA Technical Reports Server (NTRS)

Bolcar, Matthew R.; Lyon, Richard G.

2011-01-01

Nulling interferometry is a technique for imaging exoplanets in which light from the parent star is suppressed using destructive interference. Light from the star is divided into two beams and a phase shift of radians is introduced into one of the beams. When the beams are recombined, they destructively interfere to produce a deep null. For monochromatic light, this is implemented by introducing an optical path difference (OPD) between the two beams equal to lambda/2, where lambda is the wavelength of the light. For broadband light, however, a different phase shift will be introduced at each wavelength and the two beams will not effectively null when recombined. Various techniques have been devised to introduce an achromatic phase shift a phase shift that is uniform across a particular bandwidth. One popular technique is to use a series of dispersive elements to introduce a wavelength-dependent optical path in one or both of the arms of the interferometer. By intelligently choosing the number, material and thickness of a series of glass plates, a nearly uniform, arbitrary phase shift can be introduced between two arms of an interferometer. There are several constraints that make choosing the number, type, and thickness of materials a difficult problem, such as the size of the bandwidth to be nulled. Several solutions have been found for bandwidths on the order of 20 to 30 percent (Delta(lambda)/lambda(sub c)) in the mid-infrared region. However, uniform phase shifts over a larger bandwidth in the visible regime between 480 to 960 nm (67 percent) remain difficult to obtain at the tolerances necessary for exoplanet detection. A configuration of 10 dispersive glass plates was developed to be used as an achromatic phase shifter in nulling interferometry. Five glass plates were placed in each arm of the interferometer and an additional vacuum distance was also included in the second arm of the interferometer. This configuration creates a phase shift of pi radians with an average error of 5.97 x 10(exp -8) radians and standard deviation of 3.07 x 10(exp -4) radians. To reduce ghost reflections and interference effects from neighboring elements, the glass plates are tilted such that the beam does not strike each plate at normal incidence. Reflections will therefore walk out of the system and not contribute to the intensity when the beams are recombined. Tilting the glass plates, however, introduces several other problems that must be mitigated: (1) the polarization of a beam changes when refracted at an interface at non-normal incidence; (2) the beam experiences lateral chromatic spread as it traverses multiple glass plates; (3) at each surface, wavelength- dependent intensity losses will occur due to reflection. For a fixed angle of incidence, each of these effects must be balanced between each arm of the interferometer in order to ensure a deep null. The solution was found using a nonlinear optimization routine that minimized an objective function relating phase shift, intensity difference, chromatic beam spread, and polarization difference to the desired parameters: glass plate material and thickness. In addition to providing a uniform, broadband phase shift, the configuration achieves an average difference in intensity transmission between the two arms of the interferometer of 0.016 percent with a standard deviation of 3.64 x 10(exp -4) percent, an average difference in polarization between the two arms of the interferometer of 5.47 x 10(exp -5) percent with a standard deviation of 1.57 x 10(exp -6) percent, and an average chromatic beam shift between the two arms of the interferometer of -47.53 microns with a wavelength-by-wavelength spread of 0.389 microns.
Comparison of elliptical and spherical mirrors for the grasshopper monochromators at SSRL

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

Waldhauer, A. P.

1989-07-01

A comparison of the performance of a spherical and elliptical mirror in the grasshopper monochromator is presented. The problem was studied by ray tracing and then tested using visible (/lambda/=633 nm) laser light. Calculations using ideal optics yield an improvement in flux by a factor of up to 2.7, while tests with visible light show an increase by a factor of 5 because the old spherical mirror is compared to a new, perfect elliptical one. The FWHM of the measured focus is 90 /mu/m with a spherical mirror, and 25 /mu/m with an elliptical one. Elliptical mirrors have been acquiredmore » and are now being installed in the two grasshoppers at SSRL.« less
Segregated tandem filter for enhanced conversion efficiency in a thermophotovoltaic energy conversion system

DOEpatents

Brown, E.J.; Baldasaro, P.F.; Dziendziel, R.J.

1997-12-23

A filter system to transmit short wavelength radiation and reflect long wavelength radiation for a thermophotovoltaic energy conversion cell comprises an optically transparent substrate segregation layer with at least one coherent wavelength in optical thickness; a dielectric interference filter deposited on one side of the substrate segregation layer, the interference filter being disposed toward the source of radiation, the interference filter including a plurality of alternating layers of high and low optical index materials adapted to change from transmitting to reflecting at a nominal wavelength {lambda}{sub IF} approximately equal to the bandgap wavelength {lambda}{sub g} of the thermophotovoltaic cell, the interference filter being adapted to transmit incident radiation from about 0.5{lambda}{sub IF} to {lambda}{sub IF} and reflect from {lambda}{sub IF} to about 2{lambda}{sub IF}; and a high mobility plasma filter deposited on the opposite side of the substrate segregation layer, the plasma filter being adapted to start to become reflecting at a wavelength of about 1.5{lambda}{sub IF}. 10 figs.
On the ordinary quiver of the symmetric group over a field of characteristic 2

NASA Astrophysics Data System (ADS)

Martin, Stuart; Russell, Lee

1997-11-01

Let [fraktur S]n and [fraktur A]n denote the symmetric and alternating groups of degree n[set membership][open face N] respectively. Let p be a prime number and let F be an arbitrary field of characteristic p. We say that a partition of n is p-regular if no p (non-zero) parts of it are equal; otherwise we call it p-singular. Let S[lambda]F denote the Specht module corresponding to [lambda]. For [lambda] a p-regular partition of n let D[lambda]F denote the unique irreducible top factor of S[lambda]F. Denote by [Delta][lambda]F =D[lambda]F [downward arrow][fraktur A]n its restriction to [fraktur A]n. Recall also that, over F, the ordinary quiver of the modular group algebra FG is a finite directed graph defined as follows: the vertices are labelled by the set of all simple FG-modules, L1, [ctdot], Lr, and the number of arrows from Li to Lj equals dimFExtFG(Li, Lj). The quiver gives important information about the block structure of G.

ZrO2-modified mesoporous nanocrystalline TiO2-xNx as efficient visible light photocatalysts.

PubMed

Wang, Xinchen; Yu, Jimmy C; Chen, Yilin; Wu, Ling; Fu, Xianzhi

2006-04-01

Mesoporous nanocrystalline TiO2-xNx and TiO2-xNx/ZrO2 visible-light photocatalysts have been prepared by a sol-gel method. The photocatalysts were characterized by XRD, N2 adsorption-desorption, TEM, XPS, UV/Vis, and IR spectroscopy. The photocatalytic activity of the samples was evaluated by the decomposition of ethylene in air under visible light (lambda > 450 nm) illumination. Results revealed that nitrogen was doped into the lattice of TiO2 by the thermal treatment of NH3-adsorbed TiO2 hydrous gels, converting the TiO2 into a visible-light responsive catalyst. The introduction of ZrO2 into TiO2-xNx considerably inhibits the undesirable crystal growth during calcination. Consequently, the ZrO2-modified TiO2-xNx displays higher porosity, higher specific surface area, and an improved thermal stability over the corresponding unmodified TiO2-xNx samples.
Morning bright light exposure has no influence on self-chosen exercise intensity and mood in overweight individuals - A randomized controlled trial.

PubMed

Knaier, Raphael; Klenk, Christopher; Königstein, Karsten; Hinrichs, Timo; Rossmeissl, Anja; Infanger, Denis; Cajochen, Christian; Schmidt-Trucksäss, Arno

2018-04-01

Overweight is a worldwide increasing public health issue. Physical exercise is a useful countermeasure. Overweight individuals choose rather low exercise intensities, but especially high exercise intensities lead to higher energy expenditure and show beneficial health effects compared to lower exercise intensities. However, especially in the morning higher exercise intensities are likely to be avoided due to higher subjective effort. Bright light exposure has shown to increase maximum performance. The aim of this study was to investigate if bright light exposure can also increase self-chosen exercise intensity. We hypothesized that morning bright light exposure increases self-chosen exercise intensity of subsequent exercise through increased mood and reduced sleepiness in overweight individuals. In this randomized controlled single-blind parallel group design, 26 overweight individuals (11 males, 15 females; age 25 ± 5.7 years; body mass index 28.9 ± 2.1 kg/m 2 ) underwent three measurement appointments. On the first appointment, subjects performed a cardiopulmonary exercise test to measure maximum oxygen uptake (VO2max). Two days later a 30-min exercise session with self-chosen exercise intensity was performed for familiarization. Then subjects were randomly allocated to bright light (~4400 lx) or a control light (~230 lx) condition. Three to seven days later, subjects were exposed to light for 30 min starting at 8:00 am, immediately followed by a 30-min exercise session with persisting light exposure. Multidimensional mood questionnaires were filled out before and after the light exposure and after the exercise session. The primary outcome was the mean power output during the exercise session and the secondary outcome the rating on the three domains (i.e. good-bad; awake-tired; calm-nervous) of the multidimensional mood questionnaire. Mean power output during the exercise session was 92 ± 19 W in bright light and 80 ± 37 W in control light, respectively. In the multivariate analysis adjusted for VO2max, the mean power output during the exercise session was 8.5 W higher (95% confidence interval -12.7, 29.7; p = 0.416) for participants in bright light compared to control light. There were no significant differences between the groups for any of the three domains of the questionnaire at any time point. This is in contrast to longer lasting intervention studies that show positive influences on mood and suggests that bright light therapy requires repetitive sessions to improve mood in overweight individuals. In conclusion bright light exposure does not acutely increase self-chosen exercise intensity or improve mood in a 30-min exercise session starting at 08:30. However, regarding the fact that overweight is a worldwide and rapidly increasing public health issue even small increases in exercise intensity may be relevant. The trend toward superiority of bright light over control light implicates that further studies may be conducted in a larger scale. VO2max: maximum oxygen uptake; 95% CI: 95% confidence interval; SD: standard deviation.
Membranous nephropathy (bubbling appearance and spike formation) without immunoglobulin deposition in a patient with systemic lupus erythematosus.

PubMed

Miura, Naoto; Mori, Yuki; Yoshino, Masabumi; Suga, Norihiro; Kitagawa, Wataru; Yamada, Harutaka; Nishikawa, Kazuhiro; Imai, Hirokazu

2008-12-01

A 53-year-old Japanese man with systemic lupus erythematosus developed proteinuria and hematuria after a urinary stone episode. A light microscopic study of a kidney biopsy specimen demonstrated a bubbling appearance and spike formation of the basement membrane. Immunofluorescent studies revealed that there were no significant depositions of immunoglobulins, such as IgG (-), IgA (-), IgM (+/-), kappa light chain (+/-), lambda light chain (+/-), or C3 (-) in the glomerular capillary wall, though C1q was present as one-plus positive staining in mesangial areas. Electron microscopic studies showed that the thickness of the basement membrane varied from thin to thick without electron dense deposits, and that the cellular components of the podocyte were irregularly present in the basement membrane. Urinary protein decreased after the usage of prednisolone and mizoribine; however, proteinuria aggravated after an episode of urinary stone during the same treatment.
Time limit and VO2 slow component at intensities corresponding to VO2max in swimmers.

PubMed

Fernandes, R J; Cardoso, C S; Soares, S M; Ascensão, A; Colaço, P J; Vilas-Boas, J P

2003-11-01

The purpose of this study was to measure, in swimming pool conditions and with high level swimmers, the time to exhaustion at the minimum velocity that elicits maximal oxygen consumption (TLim at vVO(2)max), and the corresponding VO(2) slow component (O(2)SC). The vVO(2)max was determined through an intermittent incremental test (n = 15). Forty-eight hours later, TLim was assessed using an all-out swim at vVO(2)max until exhaustion. VO(2) was measured through direct oximetry and the swimming velocity was controlled using a visual light-pacer. Blood lactate concentrations and heart rate values were also measured. Mean VO(2)max for the incremental test was 5.09 +/- 0.53 l/min and the corresponding vVO(2)max was 1.46 +/- 0.06 m/s. Mean TLim value was 260.20 +/- 60.73 s and it was inversely correlated with the velocity of anaerobic threshold (r = -0.54, p < 0.05). This fact, associated with the inverse relationship between TLim and vVO(2)max (r = -0.47, but only for p < 0.10), suggested that swimmers' lower level aerobic metabolic rate might be associated with a larger capacity to sustain that exercise intensity. O(2)SC reached 274.11 +/- 152.83 l/min and was correlated with TLim (r = 0.54), increased ventilation in TLim test (r = 0.52) and energy cost of the respiratory muscles (r = 0.51), for p < 0.05. These data suggest that O(2)SC was also observed in the swimming pool, in high level swimmers performing at vVO(2)max, and that higher TLim seems to correspond to higher expected O(2)SC amplitude. These findings seem to bring new data with application in middle distance swimming.
Germany plans 60m euro physics and medicine lab

NASA Astrophysics Data System (ADS)

Stafford, Ned

2017-09-01

A new €60m medical-physics research lab is to be built in Erlangen, Germany, by the Max Planck Institute for the Science of Light (MPL) together with the Friedrich Alexander University Erlangen-Nürnberg and the University Hospital Erlangen.
Plasticity in mesophyll volume fraction modulates light-acclimation in needle photosynthesis in two pines.

PubMed

Niinemets, Ulo; Lukjanova, Aljona; Turnbull, Matthew H; Sparrow, Ashley D

2007-08-01

Acclimation potential of needle photosynthetic capacity varies greatly among pine species, but the underlying chemical, anatomical and morphological controls are not entirely understood. We investigated the light-dependent variation in needle characteristics in individuals of Pinus patula Schlect. & Cham., which has 19-31-cm long pendulous needles, and individuals of P. radiata D. Don., which has shorter (8-17-cm-long) stiffer needles. Needle nitrogen and carbon contents, mesophyll and structural tissue volume fractions, needle dry mass per unit total area (M(A)) and its components, volume to total area ratio (V/A(T)) and needle density (D = M(A)/(V/A(T))), and maximum carboxylase activity of Rubisco (V(cmax)) and capacity of photosynthetic electron transport (J(max)) were investigated in relation to seasonal mean integrated irradiance (Q(int)). Increases in Q(int) from canopy bottom to top resulted in proportional increases in both needle thickness and width such that needle total to projected surface area ratio, characterizing the efficiency of light interception, was independent of Q(int). Increased light availability also led to larger M(A) and nitrogen content per unit area (N(A)). Light-dependent modifications in M(A) resulted from increases in both V/A(T) and D, whereas N(A) changed because of increases in both M(A) and mass-based nitrogen content (N(M)) (N(A) = N(M)M(A)). Overall, the volume fraction of mesophyll cells increased with increasing irradiance and V/A(T) as the fraction of hypodermis and epidermis decreased with increasing needle thickness. Increases in M(A) and N(A) resulted in enhanced J(max) and V(cmax) per unit area in both species, but mass-based photosynthetic capacity increased only in P. patula. In addition, J(max) and V(cmax) showed greater plasticity in response to light in P. patula. Species differences in mesophyll volume fraction explained most of the variation in mass-based needle photosynthetic capacity between species, demonstrating that differences in plastic adjustments in mass-based photosynthetic activities among these representative individuals were mainly associated with contrasting investments in mesophyll cells. Greater area-based photosynthetic plasticity in P. patula relative to P. radiata was associated with larger increases in M(A) and mesophyll volume fraction with increasing irradiance. These data collectively demonstrate that light-dependent increases in mass-based nitrogen contents and photosynthetic activities were associated with an increased mesophyll volume fraction in needles at higher irradiances. They also emphasize the importance of light-dependent anatomical modifications in determining needle photosynthetic capacity.
Characterization of highly scattering media by measurement of diffusely backscattered polarized light

DOEpatents

Hielscher, Andreas H.; Mourant, Judith R.; Bigio, Irving J.

2000-01-01

An apparatus and method for recording spatially dependent intensity patterns of polarized light that is diffusely backscattered from highly scattering media are described. These intensity patterns can be used to differentiate different turbid media, such as polystyrene-sphere and biological-cell suspensions. Polarized light from a He-Ne laser (.lambda.=543 nm) is focused onto the surface of the scattering medium, and a surface area of approximately 4.times.4 cm centered on the light input point is imaged through polarization analysis optics onto a CCD camera. A variety of intensity patterns may be observed by varying the polarization state of the incident laser light and changing the analyzer configuration to detect different polarization components of the backscattered light. Experimental results for polystyrene-sphere and Intralipid suspensions demonstrate that the radial and azimuthal variations of the observed pattern depend on the concentration, size, and anisotropy factor, g, of the particles constituting the scattering medium. Measurements performed on biological cell suspensions show that intensity patterns can be used to differentiate between suspensions of cancerous and non-cancerous cells. Introduction of the Mueller-matrix for diffusely backscattered light, permits the selection of a subset of measurements which comprehensively describes the optical properties of backscattering media.
Spectroscopy of the neutron-rich hypernucleus He Λ 7 from electron scattering

DOE PAGES

Gogami, T.; Chen, C.; Kawama, D.; ...

2016-08-12

Here, the missing mass spectroscopy of themore » $$^{7}_{\\Lambda}$$He hypernucleus was performed, using the $$^{7}$$Li$$(e,e^{\\prime}K^{+})^{7}_{\\Lambda}$$He reaction at the Thomas Jefferson National Accelerator Facility Hall C. The $$\\Lambda$$ binding energy of the ground state (1/2$$^{+}$$) was determined with a smaller error than that of the previous measurement, being $$B_{\\Lambda}$$ = 5.55 $$\\pm$$ 0.10(stat.) $$\\pm$$ 0.11(sys.) MeV. The experiment also provided new insight into charge symmetry breaking in p-shell hypernuclear systems. Finally, a peak at $$B_{\\Lambda}$$ = 3.65 $$\\pm$$ 0.20(stat.) $$\\pm$$ 0.11(sys.) MeV was observed and assigned as a mixture of 3/2$$^{+}$$ and 5/2$$^{+}$$ states, confirming the "gluelike" behavior of $$\\Lambda$$, which makes an unstable state in $$^{6}$$He stable against neutron emission.« less
A 2-lambda laser-induced flurorescence field instrument for ground-based and airborne measurements of atmospheric OH

NASA Technical Reports Server (NTRS)

Rodgers, M. O.; Bradshaw, J. D.; Sandholm, S. T.; Kesheng, S.; Davis, D. D.

1985-01-01

A number of techniques have been proposed for detecting atmospheric OH radicals. Of these, the laser-induced fluorescence (LIF) technique has been used by the largest number of investigators. One of the problems arising in connection with the implementation of this technique is related to the perturbing effect of the UV (lambda approximately 282 nm) laser beam used for OH monitoring, while another problem relates to signal extraction. Several new LIF approaches have been or are currently under development with the objective to bring both problems under control. The present paper deals with the experimental features of one of these new approaches. The considered approach is referred to as 2-lambda laser-induced fluorescence (2-lambda LIF). It is shown that the 2-lambda LIF system provides significant advantages over earlier 1-lambda LIF OH measurement instruments operating at ambient pressure.
Hybrid-Lambda: simulation of multiple merger and Kingman gene genealogies in species networks and species trees.

PubMed

Zhu, Sha; Degnan, James H; Goldstien, Sharyn J; Eldon, Bjarki

2015-09-15

There has been increasing interest in coalescent models which admit multiple mergers of ancestral lineages; and to model hybridization and coalescence simultaneously. Hybrid-Lambda is a software package that simulates gene genealogies under multiple merger and Kingman's coalescent processes within species networks or species trees. Hybrid-Lambda allows different coalescent processes to be specified for different populations, and allows for time to be converted between generations and coalescent units, by specifying a population size for each population. In addition, Hybrid-Lambda can generate simulated datasets, assuming the infinitely many sites mutation model, and compute the F ST statistic. As an illustration, we apply Hybrid-Lambda to infer the time of subdivision of certain marine invertebrates under different coalescent processes. Hybrid-Lambda makes it possible to investigate biogeographic concordance among high fecundity species exhibiting skewed offspring distribution.
Simultaneous display of two large proteins on the head and tail of bacteriophage lambda.

PubMed

Pavoni, Emiliano; Vaccaro, Paola; D'Alessio, Valeria; De Santis, Rita; Minenkova, Olga

2013-09-30

Consistent progress in the development of bacteriophage lambda display platform as an alternative to filamentous phage display system was achieved in the recent years. The lambda phage has been engineered to display efficiently multiple copies of peptides or even large protein domains providing a powerful tool for screening libraries of peptides, proteins and cDNA. In the present work we describe an original method for dual display of large proteins on the surface of lambda particles. An anti-CEA single-chain antibody fragment and green fluorescent protein or alkaline phosphatase were simultaneously displayed by engineering both gpD and gpV lambda proteins. Here we show that such modified phage particles can be used for the detection of target molecules in vitro and in vivo. Dual expression of functional moieties on the surface of the lambda phage might open the way to generation of a new class of diagnostic and therapeutic targeted nanoparticles.
Primary Dendrite Arm Spacings in Al-7Si Alloy Directionally Solidified on the International Space Station

NASA Technical Reports Server (NTRS)

Angart, Samuel; Lauer, Mark; Poirier, David; Tewari, Surendra; Rajamure, Ravi; Grugel, Richard

2015-01-01

Samples from directionally solidified Al- 7 wt. % Si have been analyzed for primary dendrite arm spacing (lambda) and radial macrosegregation. The alloy was directionally solidified (DS) aboard the ISS to determine the effect of mitigating convection on lambda and macrosegregation. Samples from terrestrial DS-experiments thermal histories are discussed for comparison. In some experiments, lambda was measured in microstructures that developed during the transition from one speed to another. To represent DS in the presence of no convection, the Hunt-Lu model was used to represent diffusion controlled growth under steady-state conditions. By sectioning cross-sections throughout the entire length of a solidified sample, lambda was measured and calculated using the model. During steady-state, there was reasonable agreement between the measured and calculated lambda's in the space-grown samples. In terrestrial samples, the differences between measured and calculated lambda's indicated that the dendritic growth was influenced by convection.
{Lambda}K*{Lambda}(1116) photoproduction and nucleon resonances

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

Kim, Sang-Ho; Kim, Hyun-Chul; Nam, Seung-il

2011-10-21

In this presentation, we report our recent studies on the {Lambda}K*{Lambda}(1116) photoproduction off the proton target, using the tree-level Born approximation, via the effective Lagrangian approach. In addition, we include the nine (three- or four-star confirmed) nucleon resonances below the threshold {radical}(s{sub th}){approx_equal}2008 MeV, to interpret the discrepancy between the experiment and previous theoretical studies, in the vicinity of the threshold region. From the numerical studies, we observe that the S{sub 11}(1535) and S11(1650) play an important role for the cross-section enhancement near the {radical}(s{sub th}). It also turns out that, in order to reproduce the data, we have themore » vector coupling constants gK*S{sub 11}(1535){Lambda} = (7.0{approx}9.0) and gK*S{sub 11}(1650){Lambda} (5.0{approx}6.0).« less
Spectroscopic studies and structure of 3-methoxy-2 -[(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde

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

Oezay, H.; Yildiz, M., E-mail: myildiz@comu.edu.tr; Uenver, H.

2013-01-15

The compound called 3-methoxy-2- [(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde has been synthesized from the reaction of 2-hydroxy-3-methoxybenzaldehyde with hexachlorocyclotriphosphazene. It has been characterized by elemental analysis, MS, IR, {sup 1}H NMR, {sup 13}C NMR, {sup 31}P NMR and UV-visible spectroscopic techniques. The structure of the title compound has been determind by X-ray analysis. Crystals are orthorhombic, space group P2{sub 1}2{sub 1}2{sub 1}, Z = 4, a = 7.705(1), b = 12.624(1), c = 17.825(2) A, R{sub 1} = 0.0390 and wR{sub 2} = 0.1074 [I > 2{sigma}(I)], respectively.
[Ru(phen)2DPPZ]2+ is in contact with DNA bases when it forms a luminescent complex with single-stranded oligonucleotides.

PubMed

Moon, Seok Joon; Kim, Jong Moon; Choi, Ji Youn; Kim, Seog K; Lee, Je Seung; Jang, Ho G

2005-05-01

The luminescence intensity of the Delta- and Lambda-enantiomer of [Ru(phen)2DPPZ]2+ ([Ru(phenanthroline)2 dipyrido[3,2-a:2',3'-c]phenazine]2+) complex enhanced upon binding to double stranded DNA, which has been known as "light switch effect". The enhancement of the luminescence required the intercalation of the large ligand between DNA base pairs. In this study, we report the enhancement in the luminescence intensity when the metal complexes bind to single stranded oligonucleotides, indicating that the "light switch effect" does not require intercalation of the large DPPZ ligand. Oligonucleotides may provide a hydrophobic cavity for the [Ru(phen)2DPPZ]2+ complex to prevent the quenching by the water molecule. In the cavity, the metal complex is in contact with DNA bases as is evidenced by the observation that the excited energy of the DNA bases transfer to the bound metal complex. However, the contact of the metal complex with DNA bases is different from the stacking of DPPZ in the intercalation pocket. In addition to the normal two luminescence lifetimes, a short lifetime in the range of 1-2 ns was found for both the delta- and lambda-enantiomer of [Ru(phen)2DPPZ]2+ when complexed with single stranded oligonucleotides, which may be assigned to the metal complex that is outside of the cavity, interacting with phosphate groups of DNA.
Influence of tensor interactions on masses and decay widths of dibaryons

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

Pang Hourong; Ping Jialun; Chen Lingzhi

The influence of gluon and Goldstone boson induced tensor interactions on the dibaryon masses and D-wave decay widths has been studied in the quark delocalization, color screening model. The effective S-D wave transition interactions induced by gluon and Goldstone boson exchanges decrease rapidly with increasing strangeness of the channel. The tensor contribution of K and {eta} mesons is negligible in this model. There is no six-quark state in the light flavor world studied so far that can become bound by means of these tensor interactions besides the deuteron. The partial D-wave decay widths of the IJ{sup p}=(1/2)2{sup +}N{omega} state tomore » spin 0 and 1 {lambda}{xi} final states are 12.0 and 21.9 keV, respectively. This is a very narrow dibaryon resonance that might be detectable in those production reactions with rich high strangeness particles through the reconstruction of the vertex mass of the decay product {lambda}{xi} by existing detectors at RHIC and COMPASS at CERN or at JHF in Japan and FAIR in Germany in the future.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Ke; Li Yanqiu; Wang Hai

Characterization of measurement accuracy of the phase-shifting point diffraction interferometer (PS/PDI) is usually performed by two-pinhole null test. In this procedure, the geometrical coma and detector tilt astigmatism systematic errors are almost one or two magnitude higher than the desired accuracy of PS/PDI. These errors must be accurately removed from the null test result to achieve high accuracy. Published calibration methods, which can remove the geometrical coma error successfully, have some limitations in calibrating the astigmatism error. In this paper, we propose a method to simultaneously calibrate the geometrical coma and detector tilt astigmatism errors in PS/PDI null test. Basedmore » on the measurement results obtained from two pinhole pairs in orthogonal directions, the method utilizes the orthogonal and rotational symmetry properties of Zernike polynomials over unit circle to calculate the systematic errors introduced in null test of PS/PDI. The experiment using PS/PDI operated at visible light is performed to verify the method. The results show that the method is effective in isolating the systematic errors of PS/PDI and the measurement accuracy of the calibrated PS/PDI is 0.0088{lambda} rms ({lambda}= 632.8 nm).« less
Few-fJ/bit data transmissions using directly modulated lambda-scale embedded active region photonic-crystal lasers

NASA Astrophysics Data System (ADS)

Takeda, Koji; Sato, Tomonari; Shinya, Akihiko; Nozaki, Kengo; Kobayashi, Wataru; Taniyama, Hideaki; Notomi, Masaya; Hasebe, Koichi; Kakitsuka, Takaaki; Matsuo, Shinji

2013-07-01

A low operating energy is needed for nanocavity lasers designed for on-chip photonic network applications. On-chip nanocavity lasers must be driven by current because they act as light sources driven by electronic circuits. Here, we report the high-speed direct modulation of a lambda-scale embedded active region photonic-crystal (LEAP) laser that holds three records for any type of laser operated at room temperature: a low threshold current of 4.8 µA, a modulation current efficiency of 2.0 GHz µA-0.5 and an operating energy of 4.4 fJ bit-1. Five major technologies make this performance possible: a compact buried heterostructure, a photonic-crystal nanocavity, a lateral p-n junction realized by ion implantation and thermal diffusion, an InAlAs sacrificial layer and current-blocking trenches. We believe that an output power of 2.17 µW and an operating energy of 4.4 fJ bit-1 will enable us to realize on-chip photonic networks in combination with the recently developed highly sensitive receivers.
Observational constraints on disc galaxy formation

NASA Astrophysics Data System (ADS)

Syer, D.; Mao, Shude; Mo, H. J.

1999-04-01

We use data from the literature to constrain theoretical models of galaxy formation. We show how to calculate the dimensionless spin parameter lambda of the haloes of disc galaxies, and we compare the distribution of lambda with that observed in cosmological N-body simulations. The agreement is excellent, which provides strong support for the hierarchical picture of galaxy formation. Assuming only that the radial surface density distribution of discs is exponential, we estimate crudely the maximum-disc mass-to-light ratio in the I band, and obtain < Upsilon_I> <~ 3.56 h, for a Hubble constant of 100 h km s^-1 Mpc^-1. We discuss this result and its limitations in relation to other independent determinations of Upsilon_I. We also define a dimensionless form of the Tully-Fisher relation, and use it to derive a value of the baryon fraction in disc galaxies; the median value is m_d = 0.084 (Upsilon_I3.56 h). Assuming that the gas fraction in galactic haloes is at most as large as that in clusters, we also conclude that < Upsilon_I> <~ 2.56 h^-1/2.
C III] Emission in Star-Forming Galaxies Near and Far

NASA Technical Reports Server (NTRS)

Rigby, J, R.; Bayliss, M. B.; Gladders, M. D.; Sharon, K.; Wuyts, E.; Dahle, H.; Johnson, T.; Pena-Guerrero, M.

2015-01-01

We measure C III Lambda Lambda 1907, 1909 Angstrom emission lines in eleven gravitationally-lensed star-forming galaxies at zeta at approximately 1.6-3, finding much lower equivalent widths than previously reported for fainter lensed galaxies (Stark et al. 2014). While it is not yet clear what causes some galaxies to be strong C III] emitters, C III] emission is not a universal property of distant star-forming galaxies. We also examine C III] emission in 46 star-forming galaxies in the local universe, using archival spectra from GHRS, FOS, and STIS on HST, and IUE. Twenty percent of these local galaxies show strong C III] emission, with equivalent widths less than -5 Angstrom. Three nearby galaxies show C III] emission equivalent widths as large as the most extreme emitters yet observed in the distant universe; all three are Wolf-Rayet galaxies. At all redshifts, strong C III] emission may pick out low-metallicity galaxies experiencing intense bursts of star formation. Such local C III] emitters may shed light on the conditions of star formation in certain extreme high-redshift galaxies.

Effects of light quality on pod elongation in soybean (Glycine max (L.) Merr.) and cowpea (Vigna unguiculata (L.) Walp.).

PubMed

Tanaka, Seiya; Ario, Nobuyuki; Nakagawa, Andressa Camila Seiko; Tomita, Yuki; Murayama, Naoki; Taniguchi, Takatoshi; Hamaoka, Norimitsu; Iwaya-Inoue, Mari; Ishibashi, Yushi

2017-06-03

Soybean pods are located at the nodes, where they are in the shadow, whereas cowpea pods are located outside of the leaves and are exposed to sunlight. To compare the effects of light quality on pod growth in soybean and cowpea, we measured the length of pods treated with white, blue, red or far-red light. In both species, pods elongated faster during the dark period than during the light period in all light treatments except red light treatment in cowpea. Red light significantly suppressed pod elongation in soybean during the dark and light periods. On the other hand, the elongation of cowpea pods treated with red light markedly promoted during the light period. These results suggested that the difference in the pod set sites between soybean and cowpea might account for the difference in their red light responses for pod growth.
Organic cation rhodamines for screening organic cation transporters in early stages of drug development.

PubMed

Ugwu, Malachy C; Oli, Angus; Esimone, Charles O; Agu, Remigius U

The aim of this study was to investigate the suitability of rhodamine-123, rhodamine-6G and rhodamine B as non-radioactive probes for characterizing organic cation transporters in respiratory cells. Fluorescent characteristics of the compounds were validated under standard in vitro drug transport conditions (buffers, pH, and light). Uptake/transport kinetics and intracellular accumulation of the compounds were investigated. Uptake/transport mechanisms were investigated by comparing the effect of pH, temperature, concentration, polarity, OCTs/OCTNs inhibitors/substrates, and metabolic inhibitors on the cationic dyes uptake in Calu-3 cells. Fluorescence stability and intensity of the compounds were altered by buffer composition, light, and pH. Uptake of the dyes was concentration-, temperature- and pH-dependent. OCTs/OCTNs inhibitors significantly reduced intracellular accumulation of the compounds. Whereas rhodamine-B uptake was sodium-dependent, pH had no effect on rhodamine-123 and rhodamine-6G uptake. Transport of the dyes across the cells was polarized: (AP→BL>BL→AP transport) and saturable: {V max =14.08±2.074, K m =1821±380.4 (rhodamine-B); V max =6.555±0.4106, K m =1353±130.4 (rhodamine-123) and V max =0.3056±0.01402, K m =702.9±60.97 (rhodamine-6G)}. The dyes were co-localized with MitoTracker®, the mitochondrial marker. Cationic rhodamines, especially rhodamine-B and rhodamine- 6G can be used as organic cation transporter substrates in respiratory cells. During such studies, buffer selection, pH and light exposure should be taken into consideration. Copyright © 2016 Elsevier Inc. All rights reserved.
Longitudinal diffusion tensor magnetic resonance imaging study of radiation-induced white matter damage in a rat model.

PubMed

Wang, Silun; Wu, Ed X; Qiu, Deqiang; Leung, Lucullus H T; Lau, Ho-Fai; Khong, Pek-Lan

2009-02-01

Radiation-induced white matter (WM) damage is a major side effect of whole brain irradiation among childhood cancer survivors. We evaluate longitudinally the diffusion characteristics of the late radiation-induced WM damage in a rat model after 25 and 30 Gy irradiation to the hemibrain at 8 time points from 2 to 48 weeks postradiation. We hypothesize that diffusion tensor magnetic resonance imaging (DTI) indices including fractional anisotropy (FA), trace, axial diffusivity (lambda(//)), and radial diffusivity (lambda( perpendicular)) can accurately detect and monitor the histopathologic changes of radiation-induced WM damage, measured at the EC, and that these changes are dose and time dependent. Results showed a progressive reduction of FA, which was driven by reduction in lambda(//) from 4 to 40 weeks postradiation, and an increase in lambda( perpendicular) with return to baseline in lambda(//) at 48 weeks postradiation. Histologic evaluation of irradiated WM showed reactive astrogliosis from 4 weeks postradiation with reversal at 36 weeks, and demyelination, axonal degeneration, and necrosis at 48 weeks postradiation. Moreover, changes in lambda(//) correlated with reactive astrogliosis (P < 0.01) and lambda( perpendicular) correlated with demyelination (P < 0.01). Higher radiation dose (30 Gy) induced earlier and more severe histologic changes than lower radiation dose (25 Gy), and these differences were reflected by the magnitude of changes in lambda(//) and lambda( perpendicular). DTI indices reflected the histopathologic changes of WM damage and our results support the use of DTI as a biomarker to noninvasively monitor radiation-induced WM damage.
Assessment of resistance risk to lambda-cyhalothrin and cross-resistance to four other insecticides in the house fly, Musca domestica L. (Diptera: Muscidae).

PubMed

Abbas, Naeem; Shad, Sarfraz Ali

2015-07-01

Lambda-cyhalothrin, a sodium channel modulator insecticide, has been used frequently for the control of house flies, Musca domestica L. (Diptera: Muscidae) worldwide, including Pakistan. This experiment was performed to determine the selection and assessment of lambda-cyhalothrin resistance evolution along with four other insecticides. After 26 generations of selection, the lambda-cyhalothrin-selected population developed 445-fold resistance to lambda-cyhalothrin compared to the susceptible population. There was low cross-resistance to bifenthrin and very low cross-resistance to methomyl, imidacloprid, and fipronil in the lambda-cyhalothrin-selected population compared to the field population (G1). Realized heritability (h (2)) of resistance to lambda-cyhalothrin, bifenthrin, methomyl, imidacloprid, and fipronil was 0.07, 0.05, 0.01, 0.08, and 0.08, respectively. The projected rate of resistance development revealed that if 90 % house flies were selected, then a tenfold increase in lethal concentration 50 occurred after 17, 20, 159, 13, and 14 generations for lambda-cyhalothrin (h (2) = 0.07, slope = 2.09), bifenthrin (h (2) = 0.05, slope = 1.73), methomyl (h (2) = 0.01, slope = 2.52), imidacloprid (h (2) = 0.08, slope = 1.89), and fipronil (h (2) = 0.08, slope = 2.03), respectively. The results of our study concluded that the house fly has the potential to develop multiple insecticide resistances following continued selection pressure with lambda-cyhalothrin. This study will be helpful for assisting the development of resistance management strategies.
Size effects of primary/secondary twins on the atomistic deformation mechanisms in hierarchically nanotwinned metals

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

Yuan, Fuping; Wu, Xiaolei

2013-05-28

A series of large-scale molecular dynamics simulations have been performed to investigate the tensile properties of nanotwinned (NT) copper with hierarchically twinned structures (HTS). For the same grain size d and the same spacing of primary twins {lambda}{sub 1}, the average flow stress first increases as the spacing of secondary twins {lambda}{sub 2} decreases, reaching a maximum at a critical {lambda}{sub 2}, and then decreases as {lambda}{sub 2} becomes even smaller. The smaller the spacing for {lambda}{sub 1}, the smaller the critical spacing for {lambda}{sub 2}. There exists a transition in dominating deformation mechanisms, occurring at a critical spacing ofmore » {lambda}{sub 2} for which strength is maximized. Above the critical spacing of {lambda}{sub 2}, the deformation mechanisms are dominated by the two Hall-Petch type strengthening mechanisms: (a) partial dislocations emitted from grain boundaries (GBs) travel across other GBs and twin boundaries (TBs); (b) partial dislocations emitted from TBs travel across other TBs. Below the critical spacing of {lambda}{sub 2}, the deformation mechanism is dominated by the two softening mechanisms: (a) Partial dislocations emitted from boundaries of the primary twins travel parallel to the TBs of the secondary twins, leading to detwinning of the secondary twins; (b) Boundaries of the primary twins shift entirely, leading to thickening in one part of primary twins and thinning in the other part of primary twins. The present results should provide insights to design the microstructures for reinforcing the mechanical properties in the NT metals with HTS.« less
RECONCILIATION OF WAITING TIME STATISTICS OF SOLAR FLARES OBSERVED IN HARD X-RAYS

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

Aschwanden, Markus J.; McTiernan, James M., E-mail: aschwanden@lmsal.co, E-mail: jimm@ssl.berkeley.ed

2010-07-10

We study the waiting time distributions of solar flares observed in hard X-rays with ISEE-3/ICE, HXRBS/SMM, WATCH/GRANAT, BATSE/CGRO, and RHESSI. Although discordant results and interpretations have been published earlier, based on relatively small ranges (<2 decades) of waiting times, we find that all observed distributions, spanning over 6 decades of waiting times ({Delta}t {approx} 10{sup -3}-10{sup 3} hr), can be reconciled with a single distribution function, N({Delta}t) {proportional_to} {lambda}{sub 0}(1 + {lambda}{sub 0{Delta}}t){sup -2}, which has a power-law slope of p {approx} 2.0 at large waiting times ({Delta}t {approx} 1-1000 hr) and flattens out at short waiting times {Delta}t {approx}
Utilization of lightflecks by seedlings of five dominant tree species of different subtropical forest successional stages under low-light growth conditions.

PubMed

Zhang, Q; Chen, Y J; Song, L Y; Liu, N; Sun, L L; Peng, C L

2012-05-01

We selected five typical tree species, including one early-successional species (ES) Pinus massoniana Lamb., two mid-successional species (MS) Schima superba Gardn. et Champ. and Castanopsis fissa (Champ. ex Benth.) Rehd. et Wils. and two late-successional species (LS) Cryptocarya concinna Hance. and Acmena acuminatissima (BI.) Merr et Perry., which represent the plants at three successional periods in Dinghushan subtropical forest succession of southern China. Potted seedlings of the five species were grown under 12% of full sunlight for 36 months. The ES and MS showed the slowest and fastest responses to lightflecks, respectively, which correlated with the rate of stomatal opening. In contrast to P. massoniana and C. concinna, the other three species exhibited a high induction loss. Early-successional species showed the lowest specific leaf area and chlorophyll content, the highest photosynthetic capacity (A(max)) and respiratory carbon losses (R(d)). Compared with ES and MS, LS showed lower A(max) and R(d). The five tree species showed a similar chlorophyll a/b ratio after long-term low-light adaptations. On the other hand, LS had a relatively higher de-epoxidation state to protect themselves from excess light during lightflecks. Our results indicated that (i) slower responses to lightflecks could partially explain why ES species could not achieve seedling regeneration in low-light conditions; (ii) fast responses to lightflecks could partially explain why MS species could achieve seedling regeneration in low-light conditions; and (iii) smaller respiratory carbon losses might confer on the LS species a competitive advantage in low-light conditions.
Relationship between Human Pupillary Light Reflex and Circadian System Status

PubMed Central

Bonmati-Carrion, Maria Angeles; Hild, Konstanze; Isherwood, Cheryl; Sweeney, Stephen J.; Revell, Victoria L.; Skene, Debra J.; Rol, Maria Angeles; Madrid, Juan Antonio

2016-01-01

Intrinsically photosensitive retinal ganglion cells (ipRGCs), whose photopigment melanopsin has a peak of sensitivity in the short wavelength range of the spectrum, constitute a common light input pathway to the olivary pretectal nucleus (OPN), the pupillary light reflex (PLR) regulatory centre, and to the suprachiasmatic nuclei (SCN), the major pacemaker of the circadian system. Thus, evaluating PLR under short wavelength light (λmax ≤ 500 nm) and creating an integrated PLR parameter, as a possible tool to indirectly assess the status of the circadian system, becomes of interest. Nine monochromatic, photon-matched light stimuli (300 s), in 10 nm increments from λmax 420 to 500 nm were administered to 15 healthy young participants (8 females), analyzing: i) the PLR; ii) wrist temperature (WT) and motor activity rhythms (WA), iii) light exposure (L) pattern and iv) diurnal preference (Horne-Östberg), sleep quality (Pittsburgh) and daytime sleepiness (Epworth). Linear correlations between the different PLR parameters and circadian status index obtained from WT, WA and L recordings and scores from questionnaires were calculated. In summary, we found markers of robust circadian rhythms, namely high stability, reduced fragmentation, high amplitude, phase advance and low internal desynchronization, were correlated with a reduced PLR to 460–490 nm wavelengths. Integrated circadian (CSI) and PLR (cp-PLR) parameters are proposed, that also showed an inverse correlation. These results demonstrate, for the first time, the existence of a close relationship between the circadian system robustness and the pupillary reflex response, two non-visual functions primarily under melanopsin-ipRGC input. PMID:27636197
Alternatives to Goodman and Kruskal's Lambda.

ERIC Educational Resources Information Center

Stavig, Gordon R.

1979-01-01

Lambda and kappa coefficients of nominal scale association are developed for research hypotheses that involve predictions of modality, agreement, or some theoretically specified configuration. The proposed new coefficient is offered as an alternative to Goodman and Kruskal's lambda. (Author/CTM)
Carbon Nanotubes Reinforced Maleic Anhydride-Modified Xylan-g-Poly(N-isopropylacrylamide) Hydrogel with Multifunctional Properties

PubMed Central

Liu, Xinxin; Song, Tao; Chang, Minmin; Meng, Ling; Wang, Xiaohui; Sun, Runcang; Ren, Junli

2018-01-01

Introducing multifunctional groups and inorganic material imparts xylan-based hydrogels with excellent properties, such as responsiveness to pH, temperature, light, and external magnetic field. In this work, a composite hydrogel was synthesized by introducing acid treated carbon nanotubes (AT-CNTs) into the maleic anhydride modified xylan grafted with poly(N-isopropylacrylamide) (MAX-g-PNIPAM) hydrogels network. It was found that the addition of AT-CNTs affected the MAX-g-PNIPAM hydrogel structure, the swelling ratio and mechanical properties, and imparted the hydrogel with new properties of electrical conductivity and near infrared region (NIR) photothermal conversion. AT-CNTs could reinforce the mechanical properties of MAX-g-PNIPAM hydrogels, being up to 83 kPa for the compressive strength when the amount was 11 wt %, which was eight times than that of PNIPAM hydrogel and four times than that of MAX-g-PNIPAM hydrogel. The electroconductibility was enhanced by the increase of AT-CNTs amounts. Meanwhile, the composite hydrogel also exhibited multiple shape memory and NIR photothermal conversion properties, and water temperature was increased from 26 °C to 56 °C within 8 min under the NIR irradiation. Thus, the AT-CNTs reinforced MAX-g-PNIPAM hydrogel possessed promising multifunctional properties, which offered many potential applications in the fields of biosensors, thermal-arrest technology, and drug-controlled release. PMID:29495611
Carbon Nanotubes Reinforced Maleic Anhydride-Modified Xylan-g-Poly(N-isopropylacrylamide) Hydrogel with Multifunctional Properties.

PubMed

Liu, Xinxin; Song, Tao; Chang, Minmin; Meng, Ling; Wang, Xiaohui; Sun, Runcang; Ren, Junli

2018-02-28

Introducing multifunctional groups and inorganic material imparts xylan-based hydrogels with excellent properties, such as responsiveness to pH, temperature, light, and external magnetic field. In this work, a composite hydrogel was synthesized by introducing acid treated carbon nanotubes (AT-CNTs) into the maleic anhydride modified xylan grafted with poly(N-isopropylacrylamide) (MAX-g-PNIPAM) hydrogels network. It was found that the addition of AT-CNTs affected the MAX-g-PNIPAM hydrogel structure, the swelling ratio and mechanical properties, and imparted the hydrogel with new properties of electrical conductivity and near infrared region (NIR) photothermal conversion. AT-CNTs could reinforce the mechanical properties of MAX-g-PNIPAM hydrogels, being up to 83 kPa for the compressive strength when the amount was 11 wt %, which was eight times than that of PNIPAM hydrogel and four times than that of MAX-g-PNIPAM hydrogel. The electroconductibility was enhanced by the increase of AT-CNTs amounts. Meanwhile, the composite hydrogel also exhibited multiple shape memory and NIR photothermal conversion properties, and water temperature was increased from 26 °C to 56 °C within 8 min under the NIR irradiation. Thus, the AT-CNTs reinforced MAX-g-PNIPAM hydrogel possessed promising multifunctional properties, which offered many potential applications in the fields of biosensors, thermal-arrest technology, and drug-controlled release.
A Multi-year Multi-passband CCD Photometric Study of the W UMa Binary EQ Tauri

NASA Astrophysics Data System (ADS)

Alton, K. B.

2009-12-01

A revised ephemeris and updated orbital period for EQ Tau have been determined from newly acquired (2007-2009) CCD-derived photometric data. A Roche-type model based on the Wilson-Devinney code produced simultaneous theoretical fits of light curve data in three passbands by invoking cold spots on the primary component. These new model fits, along with similar light curve data for EQ Tau collected during the previous six seasons (2000-2006), provided a rare opportunity to follow the seasonal appearance of star spots on a W UMa binary system over nine consecutive years. Fixed values for q, ?1,2, T1, T2, and i based upon the mean of eleven separately determined model fits produced for this system are hereafter proposed for future light curve modeling of EQ Tau. With the exception of the 2001 season all other light curves produced since then required a spotted solution to address the flux asymmetry exhibited by this binary system at Max I and Max II. At least one cold spot on the primary appears in seven out of twelve light curves for EQ Tau produced over the last nine years, whereas in six instances two cold spots on the primary star were invoked to improve the model fit. Solutions using a hot spot were less common and involved positioning a single spot on the primary constituent during the 2001-2002, 2002-2003, and 2005-2006 seasons.
Immunoglobulin light chain allelic inclusion in systemic lupus erythematosus

PubMed Central

Fraser, Louise D.; Zhao, Yuan; Lutalo, Pamela M. K.; D'Cruz, David P.; Cason, John; Silva, Joselli S.; Dunn‐Walters, Deborah K.; Nayar, Saba; Cope, Andrew P.

2015-01-01

The principles of allelic exclusion state that each B cell expresses a single light and heavy chain pair. Here, we show that B cells with both kappa and lambda light chains (Igκ and Igλ) are enriched in some patients with the systemic autoimmune disease systemic lupus erythematosus (SLE), but not in the systemic autoimmune disease control granulomatosis with polyangiitis. Detection of dual Igκ and Igλ expression by flow cytometry could not be abolished by acid washing or by DNAse treatment to remove any bound polyclonal antibody or complexes, and was retained after two days in culture. Both surface and intracytoplasmic dual light chain expression was evident by flow cytometry and confocal microscopy. We observed reduced frequency of rearrangements of the kappa‐deleting element (KDE) in SLE and an inverse correlation between the frequency of KDE rearrangement and the frequency of dual light chain expressing B cells. We propose that dual expression of Igκ and Igλ by a single B cell may occur in some patients with SLE when this may be a consequence of reduced activity of the KDE. PMID:26036683
Young Stars Emerge from Orion Head

NASA Image and Video Library

2007-05-17

This image from NASA's Spitzer Space Telescope shows infant stars "hatching" in the head of the hunter constellation, Orion. Astronomers suspect that shockwaves from a supernova explosion in Orion's head, nearly three million years ago, may have initiated this newfound birth . The region featured in this Spitzer image is called Barnard 30. It is located approximately 1,300 light-years away and sits on the right side of Orion's "head," just north of the massive star Lambda Orionis. Wisps of red in the cloud are organic molecules called polycyclic aromatic hydrocarbons. These molecules are formed anytime carbon-based materials are burned incompletely. On Earth, they can be found in the sooty exhaust from automobile and airplane engines. They also coat the grills where charcoal-broiled meats are cooked. This image shows infrared light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight. http://photojournal.jpl.nasa.gov/catalog/PIA09412
Young Stars Emerge from Orion's Head

NASA Technical Reports Server (NTRS)

2007-01-01

This image from NASA's Spitzer Space Telescope shows infant stars 'hatching' in the head of the hunter constellation, Orion. Astronomers suspect that shockwaves from a supernova explosion in Orion's head, nearly three million years ago, may have initiated this newfound birth
The region featured in this Spitzer image is called Barnard 30. It is located approximately 1,300 light-years away and sits on the right side of Orion's 'head,' just north of the massive star Lambda Orionis.
Wisps of red in the cloud are organic molecules called polycyclic aromatic hydrocarbons. These molecules are formed anytime carbon-based materials are burned incompletely. On Earth, they can be found in the sooty exhaust from automobile and airplane engines. They also coat the grills where charcoal-broiled meats are cooked.
This image shows infrared light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight.
Hepatopancreatic intoxication of lambda cyhalothrin insecticide on albino rats

PubMed Central

Elhalwagy, Manal EA; Abd-Alrahman, Sherif H; Nahas, AA; Ziada, Reem M; Mohamady, Aziza H

2015-01-01

Background: Despite the known adverse effects of lambda cyhalothrin insecticide, little is known about its hepatopancreatic intoxication effects. The present study was carried out to elucidate sub-chronic effect of Karat 2.5% EC formulation of lambda cyhalothrin on male albino rats. Methods: To explore the effects of exposure to lambda cyhalothrin on rats and its mechanism, low (1/40 of LD50, 5 mg/kg/day) and high dose (1/4 of LD50, 50 mg/kg/day) lambda cyhalothrin were applied to rats via drinking water for 3 months. Blood samples were collected monthly, and the animals were dissected for liver and pancreas’s examination at the end of the experiment. Lambda cyhalothrin administration was associated with the elevation in lipid peroxidation marker, malondialdehyde (MDA), reduction in SH-protein a major marker for antioxidant, as well as basel paraoxonase (PON) in both treated groups throughout the experimental periods. Results: In addition, significant elevations in liver enzymes alanin amino transferase, (ALT), and aspartate amino transferase (AST), as well as plasma acetylcholinesterase (AChE) and glucose level. While, significant reduction in insulin level through the experimental periods. Results of histopathological and histochemical studies showed that lambda cyhalothrin exposure induces liver and pancreatic tissues damage and depletion in glycogen content was pronounced in liver of both treated groups. Conclusions: In conclusion subchronic intoxication with lambda cyhalothrin formulation induced remarkable changes in the examined parameters. PMID:26221269
Hepatopancreatic intoxication of lambda cyhalothrin insecticide on albino rats.

PubMed

Elhalwagy, Manal Ea; Abd-Alrahman, Sherif H; Nahas, A A; Ziada, Reem M; Mohamady, Aziza H

2015-01-01

Despite the known adverse effects of lambda cyhalothrin insecticide, little is known about its hepatopancreatic intoxication effects. The present study was carried out to elucidate sub-chronic effect of Karat 2.5% EC formulation of lambda cyhalothrin on male albino rats. To explore the effects of exposure to lambda cyhalothrin on rats and its mechanism, low (1/40 of LD50, 5 mg/kg/day) and high dose (1/4 of LD50, 50 mg/kg/day) lambda cyhalothrin were applied to rats via drinking water for 3 months. Blood samples were collected monthly, and the animals were dissected for liver and pancreas's examination at the end of the experiment. Lambda cyhalothrin administration was associated with the elevation in lipid peroxidation marker, malondialdehyde (MDA), reduction in SH-protein a major marker for antioxidant, as well as basel paraoxonase (PON) in both treated groups throughout the experimental periods. In addition, significant elevations in liver enzymes alanin amino transferase, (ALT), and aspartate amino transferase (AST), as well as plasma acetylcholinesterase (AChE) and glucose level. While, significant reduction in insulin level through the experimental periods. Results of histopathological and histochemical studies showed that lambda cyhalothrin exposure induces liver and pancreatic tissues damage and depletion in glycogen content was pronounced in liver of both treated groups. In conclusion subchronic intoxication with lambda cyhalothrin formulation induced remarkable changes in the examined parameters.
Anisotropy of the penetration depth in La2-xSrxCuO4 in underdoped and overdoped regions

NASA Astrophysics Data System (ADS)

Zaleski, A. J.; Klamut, J.

1999-12-01

We present the results of measurements of the penetration depth anisotropy in pulverized, ceramic La2-xSrxCuO4. The measurements were carried out for x = 0.08, 0.1, 0.125, 0.15 and 0.2. The powdered samples, immersed in wax, were magnetically oriented in a static magnetic field of 10 T. The penetration depth in the a-b plane, icons/Journals/Common/lambda" ALT="lambda" ALIGN="TOP"/>ab, and perpendicular to it, icons/Journals/Common/lambda" ALT="lambda" ALIGN="TOP"/>icons/Journals/Common/perp" ALT="perp" ALIGN="MIDDLE"/>, were derived from alternating-current susceptibility measurements. For underdoped samples they both vary linearly with temperature (for the low-temperature region), while for the samples from the overdoped region the measured points can be fitted by an exponential function. These results support Uemura's picture (Uemura Y J 1997 Physica C 282-287 194) of crossover from Bose-Einstein condensation to a Bardeen-Cooper-Schrieffer mechanism of superconductivity. The penetration depth values extrapolated to T = 0 may be described by a quadratic function of the strontium concentration (for both icons/Journals/Common/lambda" ALT="lambda" ALIGN="TOP"/>ab and icons/Journals/Common/lambda" ALT="lambda" ALIGN="TOP"/>icons/Journals/Common/perp" ALT="perp" ALIGN="MIDDLE"/>). The anisotropy of the penetration depth as a function of the substitution shows a similar dependence to the critical temperature Tc(x).
Effects of elevated atmospheric CO2 concentration on leaf dark respiration of Xanthium strumarium in light and in darkness.

PubMed

Wang, X; Lewis, J D; Tissue, D T; Seemann, J R; Griffin, K L

2001-02-27

Leaf dark respiration (R) is an important component of plant carbon balance, but the effects of rising atmospheric CO(2) on leaf R during illumination are largely unknown. We studied the effects of elevated CO(2) on leaf R in light (R(L)) and in darkness (R(D)) in Xanthium strumarium at different developmental stages. Leaf R(L) was estimated by using the Kok method, whereas leaf R(D) was measured as the rate of CO(2) efflux at zero light. Leaf R(L) and R(D) were significantly higher at elevated than at ambient CO(2) throughout the growing period. Elevated CO(2) increased the ratio of leaf R(L) to net photosynthesis at saturated light (A(max)) when plants were young and also after flowering, but the ratio of leaf R(D) to A(max) was unaffected by CO(2) levels. Leaf R(N) was significantly higher at the beginning but significantly lower at the end of the growing period in elevated CO(2)-grown plants. The ratio of leaf R(L) to R(D) was used to estimate the effect of light on leaf R during the day. We found that light inhibited leaf R at both CO(2) concentrations but to a lesser degree for elevated (17-24%) than for ambient (29-35%) CO(2)-grown plants, presumably because elevated CO(2)-grown plants had a higher demand for energy and carbon skeletons than ambient CO(2)-grown plants in light. Our results suggest that using the CO(2) efflux rate, determined by shading leaves during the day, as a measure for leaf R is likely to underestimate carbon loss from elevated CO(2)-grown plants.
First-trimester ultrasound determination of chorionicity in twin gestations using the lambda sign: a systematic review and meta-analysis.

PubMed

Maruotti, G M; Saccone, G; Morlando, M; Martinelli, P

2016-07-01

To evaluate the accuracy of first-trimester sonographic determination of chorionicity in twin gestations using the lambda sign. Electronic databases (MEDLINE, PROSPERO, Scopus, ClinicalTrials.gov, EMBASE, Sciencedirect) were searched from their inception until April 2016. We included only study assessing the accuracy lambda sign in prediction of monochorionicity in the first trimester. Forest plots for pooled sensitivity and specificity with 95% confidence intervals (CI) were generated. In addition, symmetric summary receiver-operating characteristic curves were plotted. The area under the curve (AUC) was also computed to evaluate the overall accuracy of the diagnostic test. Nine studies, including 2292 twins, were analysed. In all of these studies, identification of the lambda sign was used to diagnose chorionicity on real-time B-mode imaging. Twins were classified as monochorionic if there was a single placental mass in the absence of the lambda sign, and dichorionic if there was a single placental mass but the lambda sign was present or the placentas were not adjacent to each other. In all nine studies, placental histology or discordant fetal sex were used to confirm chorionicity. Pooled results from the meta-analysis showed that sensitivity of the presence of the lambda sign in the prediction of dichorionicity was 99% (95% CI 98-100%), and specificity was 95% (95% CI 92-97%). Pooled sensitivity of the absence of the lambda sign in the prediction of monochorionicity was 96% (95% CI 92-98%) and pooled specificity was 99% (95% CI 98-99%). The AUC for diagnostic accuracy was 0.99, and suggested very high diagnostic accuracy. The lambda sign predicts chorionicity with a high degree of accuracy before 14 weeks of gestation. Presence of the lambda sign indicates dichorionicity, and absence of the lambda sign indicates monochorionicity. All hospitals should encourage departments providing ultrasound services to determine chorionicity when examining women with twin pregnancies in the first trimester. As determination of chorionicity is most accurate before 14 weeks when the amnion and chorion have not yet fused, the first-trimester scan in twin pregnancy is paramount. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Photosynthetic Light Responses May Explain Vertical Distribution of Hymenophyllaceae Species in a Temperate Rainforest of Southern Chile.

PubMed

Parra, María José; Acuña, Karina I; Sierra-Almeida, Angela; Sanfuentes, Camila; Saldaña, Alfredo; Corcuera, Luis J; Bravo, León A

2015-01-01

Some epiphytic Hymenophyllaceae are restricted to lower parts of the host (< 60 cm; 10-100 μmol photons m(-2) s(-1)) in a secondary forest of Southern Chile; other species occupy the whole host height (≥ 10 m; max PPFD > 1000 μmol photons m(-2) s(-1)). Our aim was to study the photosynthetic light responses of two Hymenophyllaceae species in relation to their contrasting distribution. We determined light tolerance of Hymenoglossum cruentum and Hymenophyllum dentatum by measuring gas exchange, PSI and PSII light energy partitioning, NPQ components, and pigment contents. H. dentatum showed lower maximum photosynthesis rates (A max) than H. cruentum, but the former species kept its net rates (An) near Amax across a wide light range. In contrast, in the latter one, An declined at PPFDs > 60 μmol photons m(-2) s(-1). H. cruentum, the shadiest plant, showed higher chlorophyll contents than H. dentatum. Differences in energy partitioning at PSI and PSII were consistent with gas exchange results. H. dentatum exhibited a higher light compensation point of the partitioning of absorbed energy between photochemical Y(PSII) and non-photochemical Y(NPQ) processes. Hence, both species allocated energy mainly toward photochemistry instead of heat dissipation at their light saturation points. Above saturation, H. cruentum had higher heat dissipation than H. dentatum. PSI yield (YPSI) remained higher in H. dentatum than H. cruentum in a wider light range. In both species, the main cause of heat dissipation at PSI was a donor side limitation. An early dynamic photo-inhibition of PSII may have caused an over reduction of the Qa+ pool decreasing the efficiency of electron donation to PSI. In H. dentatum, a slight increase in heat dissipation due to acceptor side limitation of PSI was observed above 300 μmol photons m(-2)s(-1). Differences in photosynthetic responses to light suggest that light tolerance and species plasticity could explain their contrasting vertical distribution.
[Illumination's effect on the growth and nitrate reductase activity of typical red-tide algae in the East China Sea].

PubMed

Li, Hong-mei; Shi, Xiao-yong; Ding, Yan-yan; Tang, Hong-jie

2013-09-01

Two typical red-tide algae, Skeletonema costatum and Prorocentrum donghaiense were selected as studied objects. The nitrate reductase activity (NRA) and the growth of the two algae under different illuminations through incubation experiment were studied. The illumination condition was consistent with in situ. Results showed that P. donghaiense and S. costatum could grow normally in the solar radiation ranged from 30-60 W x m(-2), and the growth curve was "S" type. However, when solar radiation was below 9 W x m(-2), the two alga could hardly grow. In the range of 0-60 W x m(-2), three parameters (NRAmax, micro(max), Bf) increased with the increasing of light intensity, indicating that the light intensity can influence the grow of alga indirectly through influencing the nitrate reductase activity. The micro(max) and NRAmax in unite volume of Skeletonema costatum were higher than those of Prorocentrum donghaiense, indicating that Skeletonema costatum can better utilize the nitrate than Prorocentrum donghaiense.
Max Hirsch (1875–1941): His forgotten fate and his contributions to the founding of modern rheumatology

PubMed Central

Keitel, Wolfgang; Olsson, Leif; Matteson, Eric L.

2016-01-01

Objective To elucidate the connections between balneology and rheumatology in the founding period of the discipline of rheumatology, and describe the contributions of Max Hirsch, MD in the formation of professional rheumatology societies. Material and Methods Historical documents from the medical history collection of Vogelsang–Gommern, Germany, and original personal documents of the Hirsch family and information from the medical and historical period literature were used in developing this report. Results The first efforts at organizing rheumatology as a recognized clinical and academic discipline took place in the 1920s. Many of the first proponents were balneologists who cared for patients with chronic arthritic conditions without the benefit of effective medications. Max Hirsch, MD was a major figure in the development of modern rheumatology as it emerged from the provenance of balneology and orthopedics as a recognized organized medical discipline, contributing to the founding of the German Society for Rheumatology and the International League Against Rheumatism. Conclusion Max Hirsch made significant contributions to scientific and organized rheumatology in the early days of the discipline. His contributions to the field and his fate as a Jewish physician have only recently come to light. PMID:27733939
A Hybrid Lyot Coronagraph for the Direct Imaging and Spectroscopy of Exoplanet Systems: Recent Results and Prospects

NASA Technical Reports Server (NTRS)

Trauger, John; Moody, Dwight; Gordon, Brian; Krist, John; Mawet, Dimitri

2011-01-01

We report our best laboratory contrast demonstrations achieved to date. We review the design, fabrication, performance, and future prospects of a hybrid focal plane occulter for exoplanet coronagraphy. Composed of thickness-profiled metallic and dielectric thin films vacuum deposited on a fused silica substrate, the hybrid occulter uses two superimposed thin films for control over both the real and imaginary parts of the complex attenuation pattern. Together with a deformable mirror for adjustment of wavefront phase, the hybrid Lyot coronagraph potentially exceeds billion-to one contrast over dark fields extending to within angular separations of 3 lambda/D (3 x the cosmological constant / diameter of the telescope) from the central star, over spectral bandwidths of 20 percent or more, and with throughput efficiencies up to 60 percent. We report laboratory contrasts of 3 x 10 (sup -10) degrees over 2 percent bandwidths, 6 x 10 (sup -10) degrees over 10 percent bandwidths, and 2 x 10 (sup -9) over 20 percent bandwidths, achieved across high contrast fields extending from an inner working angle of 3 lambda/D to a radius of 15 lambda/D. Occulter performance is analyzed in light of recent experiments and optical models, and prospects for further improvements are summarized. The science capabilities of the hybrid Lyot coronagraph are compared with requirements of the ACCESS mission, a representative exoplanet space telescope concept study for the direct imaging and spectroscopy of exoplanet systems. This work has been supported by NASA's Technology Demonstration for Exoplanet Missions (TDEM) program.
Multiple factors and processes involved in host cell killing by bacteriophage Mu: characterization and mapping.

PubMed

Waggoner, B T; Marrs, C F; Howe, M M; Pato, M L

1984-07-15

The regions of bacteriophage Mu involved in host cell killing were determined by infection of a lambda-immune host with 12 lambda pMu-transducing phages carrying different amounts of Mu DNA beginning at the left end. Infecting lambda pMu phages containing 5.0 (+/- 0.2) kb or less of the left end of Mu DNA did not kill the lambda-immune host, whereas lambda pMu containing 5.1 kb did kill, thus locating the right end of the kil gene between approximately 5.0 and 5.1 kb. For the Kil+ phages the extent of killing increased as the multiplicity of infection (m.o.i.) increased. In addition, killing was also affected by the presence of at least two other regions of Mu DNA: one, located between 5.1 and 5.8 kb, decreased the extent of killing; the other, located between 6.3 and 7.9 kb, greatly increased host cell killing. Killing was also assayed after lambda pMu infection of a lambda-immune host carrying a mini-Mu deleted for most of the B gene and the middle region of Mu DNA. Complementation of mini-Mu replication by infecting B+ lambda pMu phages resulted in killing of the lambda-immune, mini-Mu-containing host, regardless of the presence or absence of the Mu kil gene. The extent of host cell killing increased as the m.o.i. of the infecting lambda pMu increased, and was further enhanced by both the presence of the kil gene and the region located between 6.3 and 7.9 kb. These distinct processes of kil-mediated killing in the absence of replication and non-kil-mediated killing in the presence of replication were also observed after induction of replication-deficient and kil mutant prophages, respectively.
Study of the strong {sigma}{sub c}{yields}{lambda}{sub c}{pi},{sigma}{sub c}*{yields}{lambda}{sub c}{pi} and {xi}{sub c}*{yields}{xi}{sub c}{pi} decays in a nonrelativistic quark model

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

Albertus, C.; Nieves, J.; Hernandez, E.

We present results for the strong widths corresponding to the {sigma}{sub c}{yields}{lambda}{sub c}{pi}, {sigma}{sub c}*{yields}{lambda}{sub c}{pi} and {xi}{sub c}*{yields}{xi}{sub c}{pi} decays. The calculations have been done in a nonrelativistic constituent quark model with wave functions that take advantage of the constraints imposed by heavy quark symmetry. Partial conservation of axial current hypothesis allows us to determine the strong vertices from an analysis of the axial current matrix elements. Our results {gamma}({sigma}{sub c}{sup ++}{yields}{lambda}{sub c}{sup +}{pi}{sup +})=2.41{+-}0.07{+-}0.02 MeV, {gamma}({sigma}{sub c}{sup +}{yields}{lambda}{sub c}{sup +}{pi}{sup 0})=2.79{+-}0.08{+-}0.02 MeV, {gamma}({sigma}{sub c}{sup 0}{yields}{lambda}{sub c}{sup +}{pi}{sup -})=2.37{+-}0.07{+-}0.02 MeV, {gamma}({sigma}{sub c}*{sup ++}{yields}{lambda}{sub c}{sup +}{pi}{sup +})=17.52{+-}0.74{+-}0.12 MeV, {gamma}({sigma}{sub c}*{supmore » +}{yields}{lambda}{sub c}{sup +}{pi}{sup 0})=17.31{+-}0.73{+-}0.12 MeV, {gamma}({sigma}{sub c}*{sup 0}{yields}{lambda}{sub c}{sup +}{pi}{sup -})=16.90{+-}0.71{+-}0.12 MeV, {gamma}({xi}{sub c}*{sup +}{yields}{xi}{sub c}{sup 0}{pi}{sup +}+{xi}{sub c}{sup +}{pi}{sup 0})=3.18{+-}0.10{+-}0.01 MeV, and {gamma}({xi}{sub c}*{sup 0}{yields}{xi}{sub c}{sup +}{pi}{sup -}+{xi}{sub c}{sup 0}{pi}{sup 0})=3.03{+-}0.10{+-}0.01 MeV are in good agreement with experimental determinations.« less
Modeling of light-dependent algal photosynthesis and growth: experiments with the Barents sea diatoms Thalassiosira nordenskioldii and Chaetoceros furcellatus

NASA Astrophysics Data System (ADS)

Sakshaug, Egil; Johnsen, Geir; Andresen, Kjersti; Vernet, Maria

1991-04-01

The models by SAKSHAUGet al (1989, Limnology and Oceanography, 34, 198-205) and WEBBet al. (1974, Oecologia, 17, 281-291), for prediction of the gross growth rate of phytoplankton and short-term photosynthesis, respectively, have been modified on the basis of experiments with cultures of the centric diatoms Thalassiosira nordenskioeldii and Chaetoceros furcellatus grown at 0.5°C at combinations of two irradiances (25 and 400μmol m -2s -1) and two day-lengths (12 and 24 h). The models have one spectrum, °σ, which represents chlorophyll a (Chl a) specific absorption of photosynthetically usable light, and introduces a factor q which represents Chla per PSU, functionally defined. The models describe phytoplankton growth in terms of physiologically relevant coefficients. A properly scaled fluorescence excitation spectrum (° F) represents a more appropriate estimate for °σ than the Chl a-specific absorption spectrum ° ac judging from calculations of Φmax (= αB/° σ). On the basis of ° F, Φmax is 0.04 g-at C(mol photons) -1 for gross growth and about 0.05-0.08 for short-term carbon uptake (unfiltered samples). Calculations based on ° ac yield values for Φmax which on average are 44% lower. P vs I (photosynthesis vs irradiance) parameters are relatively independent of day-length and highly dependent on growth irradiance. The product of q [mg Chl a (mol PSU) -1] and τ (the minimum turnover time of the photosynthetic unit, h) increases 2-3-fold from high to low irradiance, thus PmB (= Φmax/ qτ) and Ik(=1/ qτ° σ)decreased. ° F decreases from high to low irradiance. Carbon-specific dark respiration rates are <0.09 day -1. Pigment ratios vary inversely with irradiance and day-length. The Chl a:C ratio is particularly low under high, strong continuous light; Chl c: Cha a ratios are higher for shalde- than for light-adapted cells, while the converse is true for the ratio of the sum of the photoprotective pigments diadinoxanthin and diatoxanthin to Chl a. The fucoxanthin: Chl a ratio is virtually independent of the light regime. The two species are similar with respect to variations in growth rate (0.09-0.33 day -1 and Ik (31-36 vs 49-100 μmol m -2 s -1 at low and high irradiance, respectively). PmB and aB for growth as well as ° F are systematically higher for C. furcellatus than for T. nordenskioeldii, while the product qτ is lower. C. furcellatus is considerably more plastic than T. nordenskioeldii with respect to pigment composition.
Modified van Vaals-Bergman coaxial cable coil (lambda coil) for high-field imaging.

PubMed

Matsuzawa, H; Nakada, T

1996-03-01

An easily constructed, low-capacitive coupling volume coil based on the van Vaals-Bergman coaxial cable coil for high field imaging is described. The coil (designated "lambda coil") was constructed using two 5/4 length 50 omega coaxial cables matched to a 50 omega transmission line with LC bridge balun. The standing wave on the single 5/4 lambda length coaxial cable provides two points of current maxima in oppositional direction. Therefore, the four current elements necessary for effective B1 field generation can be obtained by two 5/4 lambda length coaxial cables arranged analogous to 1/2 lambda T-antenna. Capacitive coupling between the coil elements and conductive samples (i.e. animals) is minimized by simply retaining the shield of the coaxial cable for the area of voltage maxima. The lambda coil exhibited excellent performance as a volume coil with a high quality factor and highly homogeneous rf fields. Because of its dramatically simple architecture and excellent performance, the lambda coil configuration appears to be an economical alternative to the original van Vaals-Bergman design, especially for research facilities with a high field magnet and limited bore space.
Wind and boundary layers in Rayleigh-Bénard convection. II. Boundary layer character and scaling.

PubMed

van Reeuwijk, Maarten; Jonker, Harm J J; Hanjalić, Kemo

2008-03-01

The scaling of the kinematic boundary layer thickness lambda(u) and the friction factor C(f) at the top and bottom walls of Rayleigh-Bénard convection is studied by direct numerical simulation (DNS). By a detailed analysis of the friction factor, a new parameterisation for C(f) and lambda(u) is proposed. The simulations were made of an L/H=4 aspect-ratio domain with periodic lateral boundary conditions at Ra=(10(5), 10(6), 10(7), 10(8)) and Pr=1. The continuous spectrum, as well as significant forcing due to Reynolds stresses, clearly indicates a turbulent character of the boundary layer, while viscous effects cannot be neglected, judging from the scaling of classical integral boundary layer parameters with Reynolds number. Using a conceptual wind model, we find that the friction factor C(f) should scale proportionally to the thermal boundary layer thickness as C(f) proportional variant lambda(Theta)/H, while the kinetic boundary layer thickness lambda(u) scales inversely proportionally to the thermal boundary layer thickness and wind Reynolds number lambda(u)/H proportional variant (lambda(Theta)/H)(-1)Re(-1). The predicted trends for C(f) and lambda(u) are in agreement with DNS results.
Neurotoxic effects of lambda-cyhalothrin modulated by piperonyl butoxide in the brain of Oreochromis niloticus.

PubMed

Piner, Petek; Üner, Nevin

2014-11-01

The objective of this research was to investigate the neurotoxic effects of pyrethroid pesticide lambda-cyhalothrin by the modulation of cytochrome P450 with piperonyl butoxide in the brain of juvenile Oreochromis niloticus. The fish were exposed to 0.48 μg L(-1) (1/6 of the 96-h LC50 ) lambda-cyhalothrin and 10 μg L(-1) piperonyl butoxide for 96 h and 15 days. tGSH, GSSG, TBARS contents, GPx, GR, GST, and AChE enzymes activities were determined by spectrophotometrical methods and Hsp70 content was analyzed by ELISA technique. Lambda-cyhalothrin had no significant effect on the components of GSH redox system, lipid peroxidation and Hsp70 levels but inhibited AChE activity. In the presence of piperonyl butoxide, lambda-cyhalothrin caused increases in tGSH, GSSG, TBARS and Hsp70 contents, GST activity, and decrease in AChE activity. Present results showed that in the presence of piperonyl butoxide, lambda-cyhalothrin caused neurotoxic effects by increasing oxidative stress. Adaptation to its oxidative stress effects may be supplied by GSH-related antioxidant system. Piperonyl butoxide revealed neurotoxic effect of lambda-cyhalothrin. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.
Preliminary use of nematic liquid crystal adaptive optics with a 2.16-meter reflecting telescope.

PubMed

Cao, Zhaoliang; Mu, Quanquan; Hu, Lifa; Li, Dayu; Peng, Zenghui; Liu, Yonggang; Xuan, Li

2009-02-16

A nematic liquid crystal adaptive optics system (NLC AOS) was assembled for a 2.16-m telescope to correct for atmospheric turbulence. LC AOS was designed and optimized with Zemax optical software. Second, an adaptive correction experiment was performed in the laboratory to test the performance of the NLC AOS. After the correction, the peak to valley (PV) and root mean square (RMS) of the wavefront were down to 0.2 lambda (lambda=633 nm) and 0.05 lambda, respectively. Finally, the star of Pollux (beta Gem) was tracked using the 2.16-m Reflecting Telescope, and real time correction of the atmospheric turbulence was performed with the NLC AOS. After the adaptive correction, the average PV and RMS of the wavefront were reduced from 11 lambda and 2.5 lambda to 2.3 lambda and 0.6 lambda, respectively. Although the intensity distribution of the beta Gem was converged and its peak was sharp, a halo still existed around the peak. These results indicated that the NLC AOS only partially corrected the vertical atmospheric turbulence. The limitations of our NLC AOS are discussed and some proposals are made.
Optical characterization of the oceanic unicellular cyanobacterium Synechococcus grown under a day-night cycle in natural irradiance

NASA Technical Reports Server (NTRS)

Stramski, Dariusz; Shalapyonok, Alexi; Reynolds, Rick A.

1995-01-01

The optical properties of the ocenanic cyanobacterium Synechococcus (clone WH8103) were examined in a nutrient-replete laboratory culture grown under a day-night cycle in natural irradiance. Measurements of the spectral absorption and beam attenuation coefficients, the size distribution of cells in suspension, and microscopic analysis of samples were made at intervals of 2-4 hours for 2 days. These measurements were used to calculate the optical properties at the level of a single 'mean' cell representative of the acutal population, specifically, the optical cross sections for spectral absorption bar-(sigma(sub a)), scattering bar-sigma(sub b))(lambda), and attentuation bar-(sigma(sub c))(lambda). In addition, concurrent determinations of chlorophyll a and particulate organic carbon allowed calculation of the Chl a- and C-specific optical coefficients. The refractive index of cells was derived from the observed data using a theory of light absorption and scattering by homogeneous spheres. Low irradiance because of cloudy skies resulted in slow division rates of cells in the culture. The percentage of dividing cells was unusually high (greater than 30%) throughout the experiment. The optical cross sections varied greatly over a day-night cycle, with a minimum near dawn or midmorning and maximum near dusk. During daylight hours, bar-(sigma(sub b)) and bar-(sigma(sub c)) can increase more than twofold and bar-(sigma(sub a) by as much as 45%. The real part of the refractive index n increaed during the day; changes in n had equal or greater effect than the varying size distribution on changes in bar-(sigma(sub c)) and bar-(sigma(sub b)). The contribution of changes in n to the increase of bar-(sigma(sub c))(660) during daylight hours was 65.7% and 45.1% on day 1 and 2, respectively. During the dark period, when bar-(sigma(sub c))(660) decreased by a factor of 2.9, the effect of decreasing n was dominant (86.3%). With the exception of a few hours during the second light period, the imaginary part of the refractive index n' showed little variation over a day-night cycle, and bar-(sigma(sub a)) was largely controlled by variations in cell size. The real part of the refractive index at lambda = 660 nm was correlated with the intracellular C concentration and the imaginary part at lambda = 678 nm with the intracellular Chl a concentration. The C-specfic attenuation coefficient showed significant diel variability, which has implications for the estimation of oceanic primary production from measurements of diel variability in beam attenuation. This study provides strong evidence that diel variability is an important component of the optical characterization of marine phytoplankton.
Historical gains in soybean (Glycine max Merr.) seed yield are driven by linear increases in light interception, energy conversion, and partitioning efficiencies

PubMed Central

Koester, Robert P.; Skoneczka, Jeffrey A.; Cary, Troy R.; Diers, Brian W.; Ainsworth, Elizabeth A.

2014-01-01

Soybean (Glycine max Merr.) is the world’s most widely grown leguminous crop and an important source of protein and oil for food and feed. Soybean yields have increased substantially throughout the past century, with yield gains widely attributed to genetic advances and improved cultivars as well as advances in farming technology and practice. Yet, the physiological mechanisms underlying the historical improvements in soybean yield have not been studied rigorously. In this 2-year experiment, 24 soybean cultivars released between 1923 and 2007 were grown in field trials. Physiological improvements in the efficiencies by which soybean canopies intercepted light (εi), converted light energy into biomass (εc), and partitioned biomass into seed (εp) were examined. Seed yield increased by 26.5kg ha–1 year–1, and the increase in seed yield was driven by improvements in all three efficiencies. Although the time to canopy closure did not change in historical soybean cultivars, extended growing seasons and decreased lodging in more modern lines drove improvements in εi. Greater biomass production per unit of absorbed light resulted in improvements in εc. Over 84 years of breeding, soybean seed biomass increased at a rate greater than total aboveground biomass, resulting in an increase in εp. A better understanding of the physiological basis for yield gains will help to identify targets for soybean improvement in the future. PMID:24790116
Evaluation of the light scattering and the turbidity microtiter plate-based methods for the detection of the excipient-mediated drug precipitation inhibition.

PubMed

Petruševska, Marija; Urleb, Uroš; Peternel, Luka

2013-11-01

The excipient-mediated precipitation inhibition is classically determined by the quantification of the dissolved compound in the solution. In this study, two alternative approaches were evaluated, one is the light scattering (nephelometer) and other is the turbidity (plate reader) microtiter plate-based methods which are based on the quantification of the compound precipitate. Following the optimization of the nephelometer settings (beam focus, laser gain) and the experimental conditions, the screening of 23 excipients on the precipitation inhibition of poorly soluble fenofibrate and dipyridamole was performed. The light scattering method resulted in excellent correlation (r>0.91) between the calculated precipitation inhibitor parameters (PIPs) and the precipitation inhibition index (PI(classical)) obtained by the classical approach for fenofibrate and dipyridamole. Among the evaluated PIPs AUC100 (nephelometer) resulted in only four false positives and lack of false negatives. In the case of the turbidity-based method a good correlation of the PI(classical) was obtained for the PIP maximal optical density (OD(max), r=0.91), however, only for fenofibrate. In the case of the OD(max) (plate reader) five false positives and two false negatives were identified. In conclusion, the light scattering-based method outperformed the turbidity-based one and could be reliably used for identification of novel precipitation inhibitors. Copyright © 2013 Elsevier B.V. All rights reserved.
Car MAX-DOAS measurements of the tropospheric Formaldehyde (HCHO) column around Bucharest (Romania) and in the Rhein-Main area (Germany)

NASA Astrophysics Data System (ADS)

Donner, Sebastian; Shaiganfar, Reza; Riffel, Katharina; Dörner, Steffen; Lampel, Johannes; Remmers, Julia; Wagner, Thomas

2016-04-01

The DOAS (differential optical absorption spectroscopy)-method analyses the absorptions of atmospheric trace gases in spectra of scattered sun light. It is an excellent way to determine the concentrations of different trace gases (e.g. NO2, SO2, HCHO…) simultaneously. MAX (Multi-AXis)-DOAS measurements observe scattered sun light under different elevation angles. From such measurements tropospheric vertical column densities (VCDs) or even vertical profiles of the measured trace gases and aerosols can be determined. We performed mobile MAX-DOAS measurements using two instruments on the roof of a car in summer 2015 in Romania during the AROMAT2 campaign and in the Winter/Spring 2016 in the Rhein-Main area (Germany). The latter is one of the densest populated areas in Germany. One instrument is a commercial Mini-MAX-DOAS instrument from the Hoffmann company, the other a self-built instrument using an AVANTES spectrometer with better optical characteristics. The instruments were looking in two different directions (one forward and one backward). Mobile MAX-DOAS measurements cover a quite large area in a short period of time. This enables to map existing gradients of concentrations of tropospheric trace gases, e.g. NO2 and HCHO. The results of those measurements then can be used to validate satellite measurements or can be compared to model results. In this study we focus on formaldehyde (HCHO). In small amounts it is emitted directly by industries and other anthropogenic and biogenic activities. Large amounts are mostly secondary produced. As it is an intermediate product of basic oxidation cycles of other hydrocarbons its concentrations are determined by the abundances of other hydrocarbons. Therefore it can be used as an indicator for volatile organic compounds (VOCs). Furthermore HCHO plays an important role in photochemical smog chemistry and tropospheric O3 chemistry. In this work we present the measurement setup and preliminary HCHO results of the AROMAT2 campaign and first results of the measurements in the Rhein-Main area. We characterize the amounts, spatial gradients and identify potential emission sources of HCHO.
Effects of tag loss on direct estimates of population growth rate

USGS Publications Warehouse

Rotella, J.J.; Hines, J.E.

2005-01-01

The temporal symmetry approach of R. Pradel can be used with capture-recapture data to produce retrospective estimates of a population's growth rate, lambda(i), and the relative contributions to lambda(i) from different components of the population. Direct estimation of lambda(i) provides an alternative to using population projection matrices to estimate asymptotic lambda and is seeing increased use. However, the robustness of direct estimates of lambda(1) to violations of several key assumptions has not yet been investigated. Here, we consider tag loss as a possible source of bias for scenarios in which the rate of tag loss is (1) the same for all marked animals in the population and (2) a function of tag age. We computed analytic approximations of the expected values for each of the parameter estimators involved in direct estimation and used those values to calculate bias and precision for each parameter estimator. Estimates of lambda(i) were robust to homogeneous rates of tag loss. When tag loss rates varied by tag age, bias occurred for some of the sampling situations evaluated, especially those with low capture probability, a high rate of tag loss, or both. For situations with low rates of tag loss and high capture probability, bias was low and often negligible. Estimates of contributions of demographic components to lambda(i) were not robust to tag loss. Tag loss reduced the precision of all estimates because tag loss results in fewer marked animals remaining available for estimation. Clearly tag loss should be prevented if possible, and should be considered in analyses of lambda(i), but tag loss does not necessarily preclude unbiased estimation of lambda(i).
Cholinergic dysfunctions and enhanced oxidative stress in the neurobehavioral toxicity of lambda-cyhalothrin in developing rats.

PubMed

Ansari, Reyaz W; Shukla, Rajendra K; Yadav, Rajesh S; Seth, Kavita; Pant, Aditya B; Singh, Dhirendra; Agrawal, Ashok K; Islam, Fakhrul; Khanna, Vinay K

2012-11-01

This study is focused on understanding the mechanism of neurobehavioral toxicity of lambda-cyhalothrin, a new generation type II synthetic pyrethroid in developing rats following their exposure from post-lactational day (PLD)22 to PLD49 and investigate whether neurobehavioral alterations are transient or persistent. Post-lactational exposure to lambda-cyhalothrin (1.0 or 3.0 mg/kg body weight, p.o.) affected grip strength and learning activity in rats on PLD50 and the persistent impairment of grip strength and learning was observed at 15 days after withdrawal of exposure on PLD65. A decrease in the binding of muscarinic-cholinergic receptors in frontocortical, hippocampal, and cerebellar membranes associated with decreased expression of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) in hippocampus was observed following exposure to lambda-cyhalothrin on PLD50 and PLD65. Exposure to lambda-cyhalothrin was also found to increase the expression of growth-associated protein-43 in hippocampus of rats on PLD50 and PLD65 as compared to controls. A significant increase in lipid peroxidation and protein carbonyl levels and decreased levels of reduced glutathione and activity of superoxide dismutase, catalase, and glutathione peroxidase in brain regions of lambda-cyhalothrin exposed rats were distinctly observed indicating increased oxidative stress. Inhibition of ChAT and AChE activity may cause down-regulation of muscarinic-cholinergic receptors consequently impairing learning activity in developing rats exposed to lambda-cyhalothrin. The data further indicate that long-term exposure to lambda-cyhalothrin at low doses may be detrimental and changes in selected behavioral and neurochemical end points may persist if exposure to lambda-cyhalothrin continues.
Bacteriophage lambda: early pioneer and still relevant

PubMed Central

Casjens, Sherwood R.; Hendrix, Roger W.

2015-01-01

Molecular genetic research on bacteriophage lambda carried out during its golden age from the mid 1950's to mid 1980's was critically important in the attainment of our current understanding of the sophisticated and complex mechanisms by which the expression of genes is controlled, of DNA virus assembly and of the molecular nature of lysogeny. The development of molecular cloning techniques, ironically instigated largely by phage lambda researchers, allowed many phage workers to switch their efforts to other biological systems. Nonetheless, since that time the ongoing study of lambda and its relatives have continued to give important new insights. In this review we give some relevant early history and describe recent developments in understanding the molecular biology of lambda's life cycle. PMID:25742714
E.S.R., magnetic, electronic and superoxide dismutase studies of imidazolate-bridged Cu(II)-Cu(II) complexes with ethylenediamine as capping ligand.

PubMed

Patel, R N; Singh, Nripendra; Shukla, K K; Gundla, V L N

2005-06-01

X-band E.S.R., magnetic and electronic spectra of some imidazolate-bridged homometallic complexes [(en)2Cu-R-Im-Cu(en)2](ClO4)3 where en, ethylenediamine; R-ImH, R = H imidazole (ImH); if R = CH3, 2-methylimidazole (M-ImH) and if R = C2H5, 2-ethylimidazole (E-ImH), and mononuclear complexes [(en)Cu-dien](ClO4)2 and [(en)Cu-PMDT](ClO4)2 where dien, diethylenetriamine; PMDT, pentamethyldiethylenetriamine have been described. Superoxide dismutase (SOD) activity has also been measured and compared with earlier reported complexes. In frozen solution at 77 K, the spectra show axial symmetry with a d(x2-y2) ground state. Difference in lambda(max) between mononuclear and binuclear complexes was found to be approximately 65-75 nm. Magnetic susceptibility and E.S.R. spectral measurements for all these binuclear complexes revealed that the copper(II) ions are involved in antiferromagnetic exchange interactions propagated by the imidazolate bridge.
A flexible 1,8-naphthyridyl derivative and its Zn(II) complexes: synthesis, structures, spectroscopic properties and recognition of Cd(II).

PubMed

Zhang, Hui-Miao; Fu, Wen-Fu; Gan, Xin; Xu, Yan-Qing; Wang, Jun; Xu, Quan-Qing; Chi, Shao-Ming

2008-12-21

A flexible ligand bis(7-methyl-1,8-naphthyridine-2-ylamino)methane (), having kappa(4)-chelating and kappa(2)-bridging modes, and its intriguing structural complexes of Zn(II) with mu-OH, kappa(1)-OAc, mu-kappa(1)-OAc and mu-kappa(2)-OAc ligands, [Zn(2)()(2)(OH)](ClO(4))(3) (), [Zn(4)()(2)(OAc)(6)(OH)(2)].CH(2)Cl(2) (.CH(2)Cl(2)) and [Zn(5)()(2)(OAc)(10)](n).4nH(2)O (.4H(2)O) were synthesized and their structures were determined by X-ray crystallography. These compounds exhibited intense blue fluorescent emissions with a lambda(max) in the range of 380-410 nm in CH(2)Cl(2), CH(3)CN and CH(3)OH solutions, and solid-state emissions centered at 416, 463, 490 and 451 nm were observed for the compounds , , and at room temperature, respectively. The investigated fluorescence properties of associated with various metal ions showed that the fluorescence enhancement of with Cd(II) was more sensitive than with other interfering cations.

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