A mechanical-force-driven physical vapour deposition approach to fabricating complex hydride nanostructures

NASA Astrophysics Data System (ADS)

Pang, Yuepeng; Liu, Yongfeng; Gao, Mingxia; Ouyang, Liuzhang; Liu, Jiangwen; Wang, Hui; Zhu, Min; Pan, Hongge

2014-03-01

Nanoscale hydrides desorb and absorb hydrogen at faster rates and lower temperatures than bulk hydrides because of their high surface areas, abundant grain boundaries and short diffusion distances. No current methods exist for the direct fabrication of nanoscale complex hydrides (for example, alanates, borohydrides) with unique morphologies because of their extremely high reducibility, relatively low thermodynamic stability and complicated elemental composition. Here, we demonstrate a mechanical-force-driven physical vapour deposition procedure for preparing nanoscale complex hydrides without scaffolds or supports. Magnesium alanate nanorods measuring 20-40 nm in diameter and lithium borohydride nanobelts measuring 10-40 nm in width are successfully synthesised on the basis of the one-dimensional structure of the corresponding organic coordination polymers. The dehydrogenation kinetics of the magnesium alanate nanorods are improved, and the nanorod morphology persists through the dehydrogenation-hydrogenation process. Our findings may facilitate the fabrication of such hydrides with improved hydrogen storage properties for practical applications.

Structural Characterization of Metal Hydrides for Energy Applications

NASA Astrophysics Data System (ADS)

George, Lyci

Hydrogen can be an unlimited source of clean energy for future because of its very high energy density compared to the conventional fuels like gasoline. An efficient and safer way of storing hydrogen is in metals and alloys as hydrides. Light metal hydrides, alanates and borohydrides have very good hydrogen storage capacity, but high operation temperatures hinder their application. Improvement of thermodynamic properties of these hydrides is important for their commercial use as a source of energy. Application of pressure on materials can have influence on their properties favoring hydrogen storage. Hydrogen desorption in many complex hydrides occurs above the transition temperature. Therefore, it is important to study the physical properties of the hydride compounds at ambient and high pressure and/or high temperature conditions, which can assist in the design of suitable storage materials with desired thermodynamic properties. The high pressure-temperature phase diagram, thermal expansion and compressibility have only been evaluated for a limited number of hydrides so far. This situation serves as a main motivation for studying such properties of a number of technologically important hydrides. Focus of this dissertation was on X-ray diffraction and Raman spectroscopy studies of Mg2FeH6, Ca(BH4) 2, Mg(BH4)2, NaBH4, NaAlH4, LiAlH4, LiNH2BH3 and mixture of MgH 2 with AlH3 or Si, at different conditions of pressure and temperature, to obtain their bulk modulus and thermal expansion coefficient. These data are potential source of information regarding inter-atomic forces and also serve as a basis for developing theoretical models. Some high pressure phases were identified for the complex hydrides in this study which may have better hydrogen storage properties than the ambient phase. The results showed that the highly compressible B-H or Al-H bonds and the associated bond disordering under pressure is responsible for phase transitions observed in brorohydrides or alanates. Complex hydrides exhibited very high compressibility suggesting possibility to destabilize them with pressure. With high capacity and favorable thermodynamics, complex hydrides are suitable for reversible storage. Further studies are required to overcome the kinetic barriers in complex hydrides by catalytic addition. A comparative study of the hydride properties with that of the constituting metal, and their inter relationships were carried out with many interesting features.

Chemical Bonding of AlH3 Hydride by Al-L2,3 Electron Energy-Loss Spectra and First-Principles Calculations

PubMed Central

Tatsumi, Kazuyoshi; Muto, Shunsuke; Ikeda, Kazutaka; Orimo, Shin-Ichi

2012-01-01

In a previous study, we used transmission electron microscopy and electron energy-loss (EEL) spectroscopy to investigate dehydrogenation of AlH3 particles. In the present study, we systematically examine differences in the chemical bonding states of Al-containing compounds (including AlH3) by comparing their Al-L2,3 EEL spectra. The spectral chemical shift and the fine peak structure of the spectra were consistent with the degree of covalent bonding of Al. This finding will be useful for future nanoscale analysis of AlH3 dehydrogenation toward the cell. PMID:28816996

Biogenic Magnetite in Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K. L.; Bazylinski, Dennis; Wentworth, Susan J.; McKay, David S.; Kirschvink, Joseph L.; Clemett, SImon J.; Bell, Mary Sue; Golden, D. C.; Gibson, Everett K., Jr.

1999-01-01

Fine-grained magnetite (Fe3O4) in martian meteorite ALH84001, generally less than 200 nm in size, is located primarily in the rims that surround the carbonate globules. There are two populations of ALH84001 magnetites, which are likely formed at low temperature by inorganic and biogenic processes. Nearly 27% of ALH84001 magnetite particles, also called elongated prisms, have characteristics which make them uniquely identifiable as biological precipitates. Additional information is contained in the original extended abstract.

Calcification of the acetabular labrum of the hip: prevalence in the general population and relation to hip articular cartilage and fibrocartilage degeneration.

PubMed

Hawellek, Thelonius; Hubert, Jan; Hischke, Sandra; Krause, Matthias; Bertrand, Jessica; Schmidt, Burkhard C; Kronz, Andreas; Püschel, Klaus; Rüther, Wolfgang; Niemeier, Andreas

2018-05-30

Meniscal calcification is considered to play a relevant role in the pathogenesis of osteoarthritis of the knee. Little is known about the biology of acetabular labral disease and its importance in hip pathology. Here, we analyze for the first time the calcification of the acetabular labrum of the hip (ALH) and its relation to hip cartilage degeneration. In this cross-sectional post-mortem study of an unselected sample of the general population, 170 ALH specimens and 170 femoral heads from 85 donors (38 female, 47 male; mean age 62.1 years) were analyzed by high-resolution digital contact radiography (DCR) and histological degeneration grade. The medial menisci (MM) from the same 85 donors served as an intra-individual reference for cartilage calcification (CC). Scanning electron microscopy (SEM), energy dispersive analysis (ED) and Raman spectroscopy were performed for characterization of ALH CC. The prevalence of CC in the ALH was 100% and that in the articular cartilage of the hip (ACH) was 96.5%. Quantitative analysis revealed that the amount of ALH CC was higher than that in the ACH (factor 3.0, p < 0.001) and in the MM (factor 1.3, p < 0.001). There was significant correlation between the amount of CC in the fibrocartilage of the left and right ALH (r = 0.70, p < 0.001). Independent of age, the amount of ALH CC correlated with histological degeneration of the ALH (Krenn score) (r = 0.55; p < 0.001) and the ACH (Osteoarthritis Research Society International (OARSI), r = 0.69; p < 0.001). Calcification of the ALH was characterized as calcium pyrophosphate dihydrate deposition. The finding that ALH fibrocartilage is a strongly calcifying tissue is unexpected and novel. The fact that ALH calcification correlates with cartilage degeneration independent of age is suggestive of an important role of ALH calcification in osteoarthritis of the hip and renders it a potential target for the prevention and treatment of hip joint degeneration.

Design tool for estimating chemical hydrogen storage system characteristics for light-duty fuel cell vehicles

DOE PAGES

Brooks, Kriston P.; Sprik, Samuel J.; Tamburello, David A.; ...

2018-04-07

The U.S. Department of Energy (DOE) developed a vehicle Framework model to simulate fuel cell-based light-duty vehicle operation for various hydrogen storage systems. This transient model simulates the performance of the storage system, fuel cell, and vehicle for comparison to Technical Targets established by DOE for four drive cycles/profiles. Chemical hydrogen storage models have been developed for the Framework for both exothermic and endothermic materials. Despite the utility of such models, they require that material researchers input system design specifications that cannot be estimated easily. To address this challenge, a design tool has been developed that allows researchers to directlymore » enter kinetic and thermodynamic chemical hydrogen storage material properties into a simple sizing module that then estimates system parameters required to run the storage system model. Additionally, the design tool can be used as a standalone executable file to estimate the storage system mass and volume outside of the Framework model. Here, these models will be explained and exercised with the representative hydrogen storage materials exothermic ammonia borane (NH 3BH 3) and endothermic alane (AlH 3).« less

Design tool for estimating chemical hydrogen storage system characteristics for light-duty fuel cell vehicles

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

Brooks, Kriston P.; Sprik, Samuel J.; Tamburello, David A.

The U.S. Department of Energy (DOE) developed a vehicle Framework model to simulate fuel cell-based light-duty vehicle operation for various hydrogen storage systems. This transient model simulates the performance of the storage system, fuel cell, and vehicle for comparison to Technical Targets established by DOE for four drive cycles/profiles. Chemical hydrogen storage models have been developed for the Framework for both exothermic and endothermic materials. Despite the utility of such models, they require that material researchers input system design specifications that cannot be estimated easily. To address this challenge, a design tool has been developed that allows researchers to directlymore » enter kinetic and thermodynamic chemical hydrogen storage material properties into a simple sizing module that then estimates system parameters required to run the storage system model. Additionally, the design tool can be used as a standalone executable file to estimate the storage system mass and volume outside of the Framework model. Here, these models will be explained and exercised with the representative hydrogen storage materials exothermic ammonia borane (NH 3BH 3) and endothermic alane (AlH 3).« less

Electron band structure of the high pressure cubic phase of AlH3

NASA Astrophysics Data System (ADS)

Shi, Hongliang; Zarifi, Niliffar; Yim, Wai-Leung; Tse, J. S.

2012-07-01

The electronic band structure of the cubic Pm3n phase of AlH3 stable above 100 GPa is examined with semi-local, Tran-Blaha modified Becke-Johnson local density approximation (TB-mBJLDA), screened hybrid density functionals and GW methods. The shift of the conduction band to higher energy with increasing pressure is predicted by all methods. However, there are significant differences in detail band structure. In the pressure range from 90 to160 GPa, semi-local, hybrid functional and TB-mBJLDA calculations predicted that AlH3 is a poor metal. In comparison, GW calculations show a gap opening at 160 GPa and AlH3 becomes a small gap semi-conductor. From the trends of the calculated band shifts, it can be concluded that the favourable conditions leading to the nesting of Fermi surfaces predicted by semi-local calculation have disappeared if the exchange term is included. The results highlight the importance of the correction to the exchange energy on the band structure of hydrogen dominant dense metal hydrides at high pressure hydrides and may help to rationalize the absence of superconductivity in AlH3 from experimental measurements.

Determination of the Three-Dimensional Morphology of ALH84001 and Biogenic MV-1 Magnetite: Comparison of Results from Electron Tomography and Classical Transmission Electron Microscopy

NASA Technical Reports Server (NTRS)

Thomas-Keprta, Kathie L.; Clemett, Simon J.; Schwartz, Cindy; Morphew, Mary; McIntosh, J. Richard; Bazylinski, Dennis A.; Kirschvink, Joseph L.; Wentworth, Susan J.; McKay, David S.; Vali, Hojatollah

2004-01-01

Dated at approximately 3.9 billion years of age, carbonate disks, found within fractures of the host rock of Martian meteorite ALH84001, have been interpreted as secondary minerals that formed at low temperature in an aqueous medium. Heterogeneously distributed within these disks are magnetite nanocrystals that are of Martian origin. Approximately one quarter of these magnetites have morphological and chemical similarities to magnetite particles produced by magnetotactic bacteria strain MV-1, which are ubiquitous in aquatic habitats on Earth. Moreover, these types of magnetite particles are not known or expected to be produced by abiotic means either through geological processes or synthetically in the laboratory. The remaining three quarters of the ALH84001 magnetites are likely products of multiple processes including, but not limited to, precipitation from a hydrothermal fluid, thermal decomposition of the carbonate matrix in which they are embedded, and extracellular formation by dissimilatory Fe-reducing bacteria. We have proposed that the origins of magnetites in ALH84001 can be best explained as the products of multiple processes, one of which is biological. Recently the three-dimensional (3-D) external morphology of the purported biogenic fraction of the ALH84001 magnetites has been the subject of considerable debate. We report here the 3-D geometry of biogenic magnetite crystals extracted from MV-1 and of those extracted from ALH84001 carbonate disks using a combination of high resolution classical and tomographic transmission electron microscopy (TEM). We focus on answering the following questions: (1) which technique provides adequate information to deduce the 3-D external crystal morphology?; and, (2) what is the precise 3-D geometry of the ALH84001 and MV-1 magnetites?

Experimental Shock Decomposition of Siderite to Magnetite

NASA Technical Reports Server (NTRS)

Bell, M. S.; Golden, D. C.; Zolensky, M. E.

2005-01-01

The debate about fossil life on Mars includes the origin of magnetites of specific sizes and habits in the siderite-rich portions of the carbonate spheres in ALH 84001 [1,2]. Specifically [2] were able to demonstrate that inorganic synthesis of these compositionally zoned spheres from aqueous solutions of variable ion-concentrations is possible. They further demonstrated the formation of magnetite from siderite upon heating at 550 C under a Mars-like CO2-rich atmosphere according to 3FeCO3 = Fe3O4 + 2CO2 + CO [3] and they postulated that the carbonates in ALH 84001 were heated to these temperatures by some shock event. The average shock pressure for ALH 84001, substantially based on the refractive index of diaplectic feldspar glasses [3,4,5] is some 35-40 GPa and associated temperatures are some 300-400 C [4]. However, some of the feldspar is melted [5], requiring local deviations from this average as high as 45-50 GPa. Indeed, [5] observes the carbonates in ALH 84001 to be melted locally, requiring pressures in excess of 60 GPa and temperatures > 600 C. Combining these shock studies with the above inorganic synthesis of zoned carbonates it seems possible to produce the ALH 84001 magnetites by the shock-induced decomposition of siderite.

First-principles prediction of low-energy structures for AlH3

NASA Astrophysics Data System (ADS)

Sun, Shoutian; Ke, Xuezhi; Chen, Changfeng; Tanaka, Isao

2009-01-01

We report density-functional calculations that predict ten different low-energy structures for aluminum hydride AlH3 with space groups Pnma , P6/mmm , I4/mcm , P4/mbm , P4/nmm , Pm3¯m , P21/m , P21/c , Pbcm , and P4/n . Phonon calculations within harmonic approximation reveal unstable modes in the P6/mmm , I4/mcm , P4/mbm , P4/nmm , Pm3¯m , P21/m , and P21/c structures, indicating that they are unstable at low temperatures. The calculations show that the thermodynamic stabilities for AlH3 with space groups Pnma , Pbcm , and P4/n are overall close to the existing α - and γ-AlH3 . From x-ray powder-diffraction patterns, the simulated main-peak positions for AlH3 (P4/n) are in good agreement with experimental δ-AlH3 . A full Rietveld analysis reveals that the fitting space groups R3¯c , Pbcm , and Pnma to the experimental x-ray powder-diffraction pattern of α-AlH3 gives almost the same satisfactory result.

Terahertz Spectroscopy of CrH (X 6Σ+) and AlH (X 1Σ+)

NASA Astrophysics Data System (ADS)

Halfen, D. T.; Ziurys, L. M.

2016-12-01

New laboratory measurements of hydrides have been carried out using terahertz direct absorption spectroscopy. Spin components of the N=2≤ftarrow 1 transition of the free radical CrH (X 6Σ+) have been recorded in the range 730-734 GHz, as well as a new measurement of the J=2≤ftarrow 1 line of AlH (X 1Σ+) near 755 GHz. Both species were created in an AC discharge of H2, argon, and metal vapor. For CrH, the chromium source was Cr(CO)6, while AlH was produced from Al(CH3)3. The J=4.5≤ftarrow 3.5 and 3.5≤ftarrow 2.5 fine-structure components were recorded for CrH, each which consists of resolved proton hyperfine doublets. For AlH, the two main quadrupole components, F=4.5≤ftarrow 3.5 and 3.5≤ftarrow 2.5, of the J=2≤ftarrow 1 transition were observed as blended features. These data were analyzed with previous 1≤ftarrow 0 millimeter/submillimeter measurements with 6Σ and 1Σ Hamiltonians for chromium and aluminum hydrides, respectively, and rotational, fine-structure (CrH only), and hyperfine constants were derived. The new measurements have resulted in refined spectroscopic parameters for both species, as well as direct measurement of the respective 2≤ftarrow 1 rotational transitions. This work also resolves a 10 MHz discrepancy in the frequency of the AlH line. CrH and AlH have already been observed in the photospheres of stars via their electronic transitions. These data will facilitate their discovery at submillimeter/terahertz wavelengths in circumstellar envelopes and perhaps in diffuse clouds.

Truncated Hexa-Octahedral Magnetite Crystals in Martian Meteorite ALH84001: Evidence of Biogenic Activity on Early Mars

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K.; Clemett, S. J.; Schwartz, C.; McIntosh, J. R.; Bazylinski, D. A.; Kirschvink, J.; McKay, D. S.; Gibson, E. K.; Vali, H.; Romanek, C. S.

2004-01-01

The landmark paper by McKay et al. [1] cited four lines of evidence associated with the Martian meteorite ALH84001 to support the hypothesis that life existed on Mars approximately 4 Ga ago. Now, more than five years later, attention has focused on the ALH84001 magnetite grains embedded within carbonate globules in the ALH84001 meteorite. We have suggested that up to approx.25% of the ALH84001 magnetite crystals are products of biological activity [e.g., 2]. The remaining magnetites lack sufficient characteristics to constrain their origin. The papers of Thomas Keprta et al. were criticized arguing that the three dimensional structure of ALH84001 magnetite crystals can only be unambiguously determined using electron tomographic techniques. Clemett et al. [3] confirmed that magnetites produced by magnetotactic bacteria strain MV-I display a truncated hexa-octahedral geometry using electron tomography and validated the use of the multi-tilt classical transmission microscopy technique used by [2]. Recently the geometry of the purported martian biogenic magnetites was shown be identical to that for MV-1 magnetites using electron tomography [6].

Neonatal case studies using active leptospermum honey.

PubMed

Mohr, Lynn D; Reyna, Roxana; Amaya, Rene

2014-01-01

Treatment of the neonatal patient with clinically complex wounds creates a challenge due to the safety and efficacy issues associated with the use of many advanced wound care products. The purpose of this case series was to present outcomes of 3 neonates with wounds of differing etiologies managed by Active Leptospermum Honey (ALH). Clinical case series. Clinical experiences with 3 neonates, 1 male and 2 females, are described. These premature infants received care at Rush University Medical Center, Houston, Texas, or Driscoll Children's Hospital, Corpus Christi, Texas. Each neonate presented with dissimilar wounds and differing treatment goals. For a premature infant with left foot ischemia, ALH dressings allowed for removal of nonviable tissue and facilitated the granulation of the open wounds. This removal of nonviable tissue coupled with the facilitation of granulation tissue enabled the premature infant's toe tips to be salvaged without requiring aggressive surgical intervention. For the 2 preterm infants with extravasation of intravenous solutions, ALH dressings allowed healing and increased tissue granulation without any noted toxicity to the wound bed. Further, the method of action of ALH includes an osmotic pull effect that reduced periwound erythema and edema. Although the use of ALH has been well documented in adult care, these case studies demonstrate its potential use in different wound etiologies in 3 neonatal patients.

ALH84001: The Key to Unlocking Secrets About Mars-15 Years and Counting

NASA Technical Reports Server (NTRS)

Gibson, Everett K.; McKay, D. S.; Thomas-Keprta, K. L.; Clemett, S. J.

2011-01-01

From the December 27, 1984 discovery of ALH84001, and its subsequent identification as a sample of Mars in 1993, mystery and debate has surrounded the meteorite [1]. With the realization that the ALH84001 sample was a orthopyroxenite and one of the oldest SNC meteorites (approx.4.09 Ga) [2] available to study, important and critical information about the Martian hydrosphere and atmosphere along with the early history and evolution of the planet could be obtained by studying the unique carbonate globules (approx.3.9 Ga) in the sample [3]. The initial work showed the carbonate globules were deposited within fractures and cracks in the host-orthopyroxene by low-temperature aqueous fluids [4]. Ideas that the carbonates were formed at temperatures [5] approaching 800 C were ruled out by later experiments [6]. The 1996 announcement by McKay et al. [7] that ALH84001 contained features which could be interpreted as having a biogenic origin generated considerable excitement and criticism. The NASA Administrator Dan Golden said the 1996 ALH84001 announcement saved NASAs Mars planetary exploration program and injected $6 billion dollars over five years into the scientific research and analysis efforts [8]. All of the original four lines of evidence for possible biogenic features within ALH84001 offered by McKay et al. have withstood the test of time. Criticism has been directed at the interpretation of the 1996 analytical data. Research has expanded to other SNC meteorites. Despite the numerous attacks on the ideas, the debate continues after 15 years. The 2009 paper by Thomas-Keprta et al. [9] on the origins of a suite of magnetites within the ALH84001 has offered strong arguments that some of the magnetites can only be formed by biogenic processes and not from thermal decomposition or shock events which happened to the meteorite. NASA s Astrobiology Institute was formed from the foundation laid by the ALH84001 hypothesis of finding life beyond the Earth. The strong astrobiology outreach programs have expanded because of the work done on the Martian meteorites. De-spite the criticism on the biogenic-like features in ALH84001, the meteorite has opened a window into the early history of Mars. Clearly low-temperature fluids have left their signatures within the ALH84001 meteorite and subsequent cratering events on Mars have been recorded on observable features within the meteorite. The 15 years of detailed study on ALH84001 and its unique carbonate globules have clearly shown formational and secondary processes at work on Mars. Now we need a well-documented Mars sample return mission.

Focused Ion Beam Microscopy of ALH84001 Carbonate Disks

NASA Technical Reports Server (NTRS)

Thomas-Keprta, Kathie L.; Clemett, Simon J.; Bazylinski, Dennis A.; Kirschvink, Joseph L.; McKay, David S.; Vali, Hojatollah; Gibson, Everett K., Jr.; Romanek, Christopher S.

2005-01-01

Our aim is to understand the mechanism(s) of formation of carbonate assemblages in ALH84001. A prerequisite is that a detailed characterization of the chemical and physical properties of the carbonate be established. We present here analyses by transmission electron microscopy (TEM) of carbonate thin sections produced by both focused ion beam (FIB) sectioning and ultramicrotomy. Our results suggest that the formation of ALH84001 carbonate assemblages were produced by considerably more complex process(es) than simple aqueous precipitation followed by partial thermal decomposition as proposed by other investigators [e.g., 1-3].

Extent of Atypical Hyperplasia Stratifies Breast Cancer Risk in Two Independent Cohorts of Women

PubMed Central

Degnim, Amy C.; Dupont, William D.; Radisky, Derek C.; Vierkant, Robert A.; Frank, Ryan D.; Frost, Marlene H.; Winham, Stacey J.; Sanders, Melinda E.; Smith, Jeffrey R.; Page, David L.; Hoskin, Tanya L.; Vachon, Celine M.; Ghosh, Karthik; Hieken, Tina J.; Denison, Lori A.; Carter, Jodi M.; Hartmann, Lynn C.; Visscher, Daniel W.

2016-01-01

Background Women with atypical hyperplasia (AH) on breast biopsy have a substantially increased risk of breast cancer (BC). Here we report BC risk with AH extent and subtype in two separate cohorts. Methods All samples containing AH were included from two cohorts of benign breast disease, Mayo Clinic and Nashville. Histology review quantified the number of foci of atypical ductal hyperplasia (ADH) and atypical lobular hyperplasia (ALH). BC risk was stratified for number of AH foci within AH subtypes. Results The study included 708 Mayo and 466 Nashville AH subjects. In the Mayo Cohort, increasing foci of AH was associated with a significant increase in risk of BC, both for ADH (RR’s of 2.61, 5.21, and 6.36 for 1, 2, and 3+ foci, p=0.006 for linear trend) and for ALH (RR’s of 2.56, 3.50, and 6.79 for 1, 2, and 3+ foci, p=0.001 for linear trend). In the Nashville Cohort, RR’s of BC for ADH were 2.70, 5.17, and 15.06 for 1, 2, and 3+ foci respectively (p<0.001 for linear trend); for ALH, RR’s also increased but not significantly (2.61, 3.48, and 4.02, p=0.148). Combining both Mayo and Nashville samples, risk increased significantly for 1, 2, and 3+ foci: RR’s of 2.65, 5.19, and 8.94 for ADH (p<0.001), and 2.58, 3.49, and 4.97 for ALH (p=0.001). Conclusions In two independent cohort studies of benign breast disease, extent of atypia stratifies long-term breast cancer risk for ADH and ALH. PMID:27352219

Petrologic and oxygen isotopic study of ALH 85085-like chondrites

NASA Astrophysics Data System (ADS)

Prinz, M.; Weisberg, M. K.; Clayton, R. N.; Mayeda, T. K.; Ebihara, M.

1994-07-01

Four meteorites (PAT 91546, PCA 91328, PCA 91452, PCA 91467) petrologically similar to ALH 85085 chondrite have now been found. Previous studies of ALH 85085 showed it be a new kind of CR-related microchondrule-bearing chondrite, although one called it a sub-chondrite. The purpose of this study is to learn more about ALH 85085-like meteorites and their relationship to CR and CR-related (LEW 85332, Acfer 182, Bencubbin) chondrites. The methods used included petrology, INA bulk chemical analysis (PAT 91546, PCA 91467), and O isotopic analyses of the whole rocks and separated chondrules and dark inclusions (DIs) from PAT 91546. Since microchondrules and fragments are approximately 20 microns it was necessary to analyze composite samples for O; one was of approximately 100 chondrules, and another was of 5 DIs. Petrologically, the four meteorites are similar to ALH 85085, and there is no basis for determining if all of them, or any combinations, are paired. Mineralogically, olivine and pyroxene are highly magnesian FeNi metal generally has 3-10% Ni, and has a positive Ni-Co correlation similar to that in CR and CR-related chondrites. Refractory inclusions are similar in size to the chondrules and have the following assemblages: (1) hibonite-perovskite, (2) melilite-fassaite-forsterite, (3) grossite (Ca-dialuminate)-melilite-perovskite, (4) spinel-melilite, and (5) spinel-pyroxene aggregates. Chemically, INA analyses indicate that PAT 91546 and PCA 91467 are generally similar to ALH 85085. Oxygen isotopic analyses of the four whole-rock compositions fall along the CR mixing line as does ALH 85085; they are also close to LEW 85332, Acfer 182, and Bencubbin. This supports the concept that these are all CR-related chondrites. Even stronger support is found in the compositions of the chondrules and DIs in PAT 91546, which also plot on or near the CR line.

Modern terrestrial analogues for the carbonate globules in Martian meteorite ALH84001.

PubMed

Kazmierczak, Józef; Kempe, Stephan

2003-04-01

Modern carbonate globules, located in cracks of submerged volcanic rocks and in calcareous pinnacles in alkaline (sodic) Lake Van, Turkey, appear to be analogues for the approximately 3.9 billion-year-old carbonate globules in Martian meteorite ALH84001. These terrestrial globules have similar diameters and are chemically and mineralogically zoned. Furthermore, they display surface and etching structures similar to those described from ALH84001, which were interpreted as fossilized microbial forms. These terrestrial carbonates formed at low temperatures where Ca-rich groundwaters enter the lake. Chemical, mineralogical, microbiological, and biomolecular methods were used in an attempt to decipher the process responsible for the genesis of these structures. Although the exact mode of formation of Lake Van carbonates remains an enigma, their similarity to the Martian globules indicates that the ALH84001 carbonates may have formed in similar setting on ancient Mars.

Breast Cancer Risk by Extent and Type of Atypical Hyperplasia: An Update from the Nurses’ Health Studies

PubMed Central

Collins, Laura C.; Aroner, Sarah; Connolly, James L.; Colditz, Graham A.; Schnitt, Stuart J.; Tamimi, Rulla M.

2015-01-01

Background Women with atypical hyperplasia (AH) on a benign breast biopsy (BBB) are at increased risk for the development of breast cancer. However, the relationship between type and extent of AH (atypical ductal hyperplasia (ADH) vs. atypical lobular hyperplasia (ALH)) and magnitude of breast cancer risk is not well-defined. Methods We conducted a nested case-control study of benign breast disease and breast cancer risk. Women with breast cancer and a prior BBB (cases=488) were matched to women with a prior BBB but free from breast cancer (controls=1907). BBB slides were reviewed and categorized as either non-proliferative, proliferative without atypia, or AH (ADH or ALH). The number of foci of AH was also recorded. Results Among women with ADH, the inter-relationship between extent of atypia and breast cancer risk was not significant (OR=3.5; 95%CI 2.2-5.6 for 1-2 foci, OR= 2.7; 95%CI 1.4-5.1 for ≥3 foci; p=0.58). Similarly, while the risk with ALH was higher for those with ≥3 foci than for those with <3 foci, the difference was not statistically significant (OR=5.2; 95%CI 2.7-10.0 for 1-2 foci; OR=8.0; 95%CI 4.5-14.2 for ≥3 foci; p=0.66). Conclusion This analysis demonstrates that the extent of ADH or ALH did not significantly contribute to breast cancer risk. The lack of a significant dose-response relationship between extent and type of atypia and breast cancer risk suggests that it would be premature to use extent of atypia to influence management decisions in women with ADH or ALH. PMID:26565738

ALH84001: The Key to Unlocking Secrets About Mars-15 Years and Counting

NASA Technical Reports Server (NTRS)

Gibson, Everett K.

2011-01-01

From the December 27, 1984 discovery of ALH84001, and its subsequent identification as a sample of Mars in 1993, mystery and debate has surrounded the meteorite. With the realization that the ALH84001 sample was a orthopyroxenite and one of the oldest SNC meteorites (4.09 Ga) available to study, important and critical information about the Martian hydrosphere and atmosphere along with the early history and evolution of the planet could be obtained by studying the unique carbonate globules (3.9 Ga) in the sample. The initial work showed the carbonate globules were deposited within fractures and cracks in the host-orthopyroxene by low-temperature aqueous fluids. Ideas that the carbonates were formed at temperatures approaching 800oC were ruled out by later experiments. The 1996 announcement by McKay et al. that ALH84001 contained features which could be interpreted as having a biogenic origin generated considerable excitement and criticism. The NASA Administrator Dan Golden said the 1996 ALH84001 announcement saved NASA s Mars planetary exploration program and injected $6 billion dollars over five years into the scientific research and analysis efforts. All of the original four lines of evidence for possible biogenic features within ALH84001 offered by McKay et al. have withstood the test of time. Criticism has been directed at the interpretation of the 1996 analytical data. Research has expanded to other SNC meteorites. Despite the numerous attacks on the ideas, the debate continues after 15 years. The 2009 paper by Thomas-Keprta et al. on the origins of a suite of magnetites within the ALH84001 has offered strong arguments that some of the magnetites can only be formed by biogenic processes and not from thermal decomposition or shock events which happened to the meteorite. NASA s Astrobiology Institute was formed from the foundation laid by the ALH84001 hypothesis of finding life beyond the Earth. The strong astrobiology outreach programs have expanded because of the work done on the Martian meteorites. Despite the criticism on the biogenic-like features in ALH84001, the meteorite has opened a window into the early history of Mars. Clearly low-temperature fluids have left their signatures within the ALH84001 meteorite and subsequent cratering events on Mars have been recorded on observable features within the meteorite. The 15 years of detailed study on ALH84001 and its unique carbonate globules have clearly shown formational and secondary processes at work on Mars. The evidence for biogenic processes operating on early Mars along with ground water activity within the last 15% of the life of Mars offers clear evidence that another niche for life may be possible within our solar system. Now we need a well-documented Mars sample return mission.

LEW85332: A C2 Chondrite in the CR Clan

NASA Astrophysics Data System (ADS)

Prinz, M.; Weisberg, M. K.; Brearley, A.; Grady, M. M.; Pillinger, C.; Clayton, R. N.; Mayeda, T. K.

1992-07-01

Introduction. LEW85332 was described as a unique C3 chondrite [1] and we undertook this study to learn more about its relationship to other carbonaceous chondrites. We find it to be a C2 chondrite with significant similarites to CR2 chondrites. This linkage extends to the ALH85085 [2] and Acfer 182 [3,4] chondrites, although there are some important differences among them. Petrologic and isotopic similarities define the CR clan, which consists of CR chondrites and their three relatives noted above (and Bencubbin). Some differences are due to major component abundances (chondrules, matrix, metal), and some to minor differences between components, but the similarities are greater and define the clan. Results. Petrogically, LEW85332 has over 60% (vol) chondrules, about 30% matrix and matrix clasts, and about 4-7% metal. Extensive weathering makes modal abundances uncertain. Chondrules are anhydrous, about 170 micrometers wide [1] and of all textural types. ALH85085 chondrules average 20 micrometers and are mainly pyroxene-rich, whereas Acfer 182 is more like LEW85332. Matrix is hydrous and occurs as interstitial matrix, matrix clasts, and chondrule rims [5]. The matrix contains phyllosilicates and magnetite framboids. Matrix clasts are not foreign [1], but part of the chondrite, making it C2. This is also the case for Acfer 182 [3], and perhaps ALH85085. Phyllosilicates are mainly saponite and serpentine [5], and their composition is similar to that in CR chondrites. The water/rock ratio was low. Metal abundances in LEW85332 [1] are lower than in Acfer 182 (9.3 vol%) [4] and ALH85085 (22%) [6]. However, FeNi composition is the same, with a positive Ni-Co trend equivalent to the solar abundance ratio. This is the same as that in CR chondrites [7]. LEW85332 contains 0.5% carbon, combusting between 200 and 500 degrees C, indicating fine-grained, poorly crystalline carbon, or organic material. It contains 259 ppm nitrogen with delta^15N = +249o/oo. Most nitrogen is released between 200 and 500 degrees C, but at 325 C the delta^15N reaches +306o/oo indicating at least two N-bearing components with differing C/N atomic ratios. The LEW85332 nitrogen isotopic composition is intermediate between ALH85085, Acfer 182 and CR chondrites, closer to CR. The extremely heavy, high- temperature component found in ALH85085 is absent (or nearly so) in LEW85332. Nitrogen abundance is similar to ALH85085, but lower than in CRs. The oxygen isotopic composition of LEW85332 is delta^18O = -0.92, delta^17O = -1.93. This, plus ALH85085 and Acfer 182 define a line (figure) identical to that of the CR chondrite mixing line (slope = 0.7) [7]. The composition of LEW85332 is close to that of unaltered olivine and pyroxene in Renazzo and Al Rais. Conclusions. (1) The important similarities between components in LEW85332 and CR2 chondrites put it in the CR clan. (2) Recognition of LEW85332, Acfer 182, and ALH85085 as relatives in the CR clan indicates that carbonaceous chondrites can no longer be classified only into coherent groups with highly similar characteristics. Recognition of clan relationships will be needed for IDPs and micrometeorites. (3) LEW85332, Acfer 182, and ALH85085 contain hydrous matrices and anhydrous chondrules, and the implications of this observation requires further study. References. [1] Rubin, A.E. and Kallemeyn, G.W. (1990) Meteoritics 25, 215-225. [2] Weisberg, M.K. et al. (1990) Meteoritics 25, 269-279. [3] Prinz, M. and Weisberg, M.K. (1992) LPSCXXIII, 1109-1110. [4] Bischoff, A. et al. (1992) Acfer 182 ms. GCA (in press). [5] Brearley, A.J. (1992) LPSCXXIII, 155-156. [6] Weisberg, M.K. et al. (1988) EPSL 91, 19-32. [7] Weisberg, M.K. et al. (1992) CR chondrite ms. GCA (in press).

Solid State NMR Studies of the Aluminum Hydride Phases

NASA Technical Reports Server (NTRS)

Hwang, Son-Jong; Bowman, R. C., Jr.; Graetz, Jason; Reilly, J. J.

2006-01-01

Several solid state NMR techniques including magic-angle-spinning (MAS) and multiple-quantum (MQ) MAS experiments have been used to characterize various AlH3 samples. MAS-NMR spectra for the 1H and 27Al nuclei have been obtained on a variety of AlH3 samples that include the (beta)- and (gamma)- phases as well as the most stable (alpha)-phase. While the dominant components in these NMR spectra correspond to the aluminum hydride phases, other species were found that include Al metal, molecular hydrogen (H2), as well as peaks that can be assigned to Al-O species in different configurations. The occurrence and concentration of these extraneous components are dependent upon the initial AlH3 phase composition and preparation procedures. Both the (beta)-AlH3 and (gamma)-AlH3 phases were found to generate substantial amounts of Al metal when the materials were stored at room temperature while the (alpha)-phase materials do not exhibit these changes.

SXRF determination of trace elements in chondrule rims in the unequilibrated CO3 chondrite, ALH A77307

NASA Technical Reports Server (NTRS)

Brearley, Adrian J.; Bajt, Sasa; Sutton, Steve R.; Papike, J. J.

1993-01-01

The concentrations of Ni, Cu, Zn, Ga, Ge, and Se in five chondrule rims in the CO3 chondrite ALH A77307 (3.0) using the synchrotron x-ray fluorescence (SXRF) microprobe at Brookhaven National Laboratory were determined. The data show that the trace element chemistry of rims on different chondrules is remarkably similar, consistent with data obtained for the major elements by electron microprobe. These results support the idea that rims are not genetically related to individual chondrules, but all sampled the same reservoir of homogeneously mixed dust. Of the trace elements analyzed Zn and Ga show depletions relative to CI chondrite values, but in comparison with bulk CO chondrites all the elements are enriched by approximately 1.5 to 3.5 x CO. The high concentrations of the highly volatile elements Se and Ga and moderately volatile Zn (1.5 to 2 x CO) in rims show that matrix is the major reservoir of volatile elements in ALH A77307.

Sn2+-Stabilization in MASnI3 perovskites by superhalide incorporation.

PubMed

Xiang, Junxiang; Wang, Kan; Xiang, Bin; Cui, Xudong

2018-03-28

Sn-based hybrid halide perovskites are a potential solution to replace Pb and thereby reduce Pb toxicity in MAPbI 3 perovskite-based solar cells. However, the instability of Sn 2+ in air atmosphere causes a poor reproducibility of MASnI 3 , hindering steps towards this goal. In this paper, we propose a new type of organic metal-superhalide perovskite of MASnI 2 BH 4 and MASnI 2 AlH 4 . Through first-principles calculations, our results reveal that the incorporation of BH 4 and AlH 4 superhalides can realize an impressive enhancement of oxidation resistance of Sn 2+ in MASnI 3 perovskites because of the large electron transfer between Sn 2+ and [BH 4 ] - /[AlH 4 ] - . Meanwhile, the high carrier mobility is preserved in these superhalide perovskites and only a slight decrease is observed in the optical absorption strength. Our studies provide a new path to attain highly stable performance and reproducibility of Sn-based perovskite solar cells.

Sn2+—Stabilization in MASnI3 perovskites by superhalide incorporation

NASA Astrophysics Data System (ADS)

Xiang, Junxiang; Wang, Kan; Xiang, Bin; Cui, Xudong

2018-03-01

Sn-based hybrid halide perovskites are a potential solution to replace Pb and thereby reduce Pb toxicity in MAPbI3 perovskite-based solar cells. However, the instability of Sn2+ in air atmosphere causes a poor reproducibility of MASnI3, hindering steps towards this goal. In this paper, we propose a new type of organic metal-superhalide perovskite of MASnI2BH4 and MASnI2AlH4. Through first-principles calculations, our results reveal that the incorporation of BH4 and AlH4 superhalides can realize an impressive enhancement of oxidation resistance of Sn2+ in MASnI3 perovskites because of the large electron transfer between Sn2+ and [BH4]-/[AlH4]-. Meanwhile, the high carrier mobility is preserved in these superhalide perovskites and only a slight decrease is observed in the optical absorption strength. Our studies provide a new path to attain highly stable performance and reproducibility of Sn-based perovskite solar cells.

Breast cancer risk by extent and type of atypical hyperplasia: An update from the Nurses' Health Studies.

PubMed

Collins, Laura C; Aroner, Sarah A; Connolly, James L; Colditz, Graham A; Schnitt, Stuart J; Tamimi, Rulla M

2016-02-15

Women with atypical hyperplasia (AH) on a benign breast biopsy specimen are at increased risk for the development of breast cancer. However, the relation between the type and extent of AH (atypical ductal hyperplasia [ADH] vs atypical lobular hyperplasia [ALH]) and the magnitude of the breast cancer risk is not well defined. A nested case-control study of benign breast disease and breast cancer risk was conducted. Women with breast cancer and prior benign breast biopsy findings (488 cases) were matched to women with prior benign breast biopsy findings who were free from breast cancer (1907 controls). Benign breast biopsy slides were reviewed and categorized as nonproliferative, proliferative without atypia, or AH (ADH or ALH). The number of foci of AH was also recorded. Among women with ADH, the interrelation between the extent of atypia and breast cancer risk was not significant (odds ratio [OR] for 1 or 2 foci, 3.5; 95% confidence interval [CI], 2.2-5.6; OR for ≥3 foci, 2.7; 95% CI, 1.4-5.1; P = .41). Similarly, although the risk with ALH was higher for those with ≥3 foci than for those with <3 foci, the difference was not statistically significant (OR for 1 or 2 foci, 5.2; 95% CI, 2.7-10.0; OR for ≥3 foci, 8.0; 95% CI, 4.5-14.2; P = .19). This analysis demonstrates that the extent of ADH or ALH does not significantly contribute to breast cancer risk. The lack of a significant dose-response relation between the extent and type of atypia and breast cancer risk suggests that it would be premature to use the extent of atypia to influence management decisions for women with ADH or ALH. © 2015 American Cancer Society.

Search for Unique Organic Biomarkers in ALH84001

NASA Technical Reports Server (NTRS)

Zare, Richard N.

1999-01-01

Four goals were outlined for this project. These were: [1] to reproduce the measurement of polycyclic aromatic hydrocarbons (PAHS) in ALH84001 with both a higher spatial resolution and sensitivity than has been previously reported; [2] to extend such measurements to include other members of the Martian SNC (Shergotties, Nahklites, and Chassigny) meteorite clan, in particular the Antarctic Martian meteorite EETA79001; [3] to address issues of potential organic contamination, because at present very little is known about the effect of terrestrial weathering in the Antarctic environment as it pertains to perturbing an indigenous organic distribution within a meteoritic matrix; and [4] to diversify the range of organic compounds studied to include species that can serve as unique biological markers - "molecular fossils" - derived from once living organisms. In order to achieve this, three specific goals were outlined for the funding period 06/01/97 to 02/28/98. They were: [1] to investigate the effects of terrestrial weathering and organic contamination of meteoritic samples collected from Antarctica; [2] to reproduce and extend upon the measurements of PAHs in ALH84001 with the aim of establishing or refuting the indigeneity of these species; and [3] to extend the analysis of organic compounds in ALH84001 and EETA79001 to address compounds that are considered to be more biologically relevant than PAHS. All three were successfully accomplished, as detailed in the previous performance report. In brief, however, the results achieved were to establish that the PAHs found in ALH84001 were indigenous and not due to contamination, and to determine that a novel and sensitive technique in meteoritic work, capillary zone electrophoresis (CE), could indeed detect amino acids, a potential class of biomarker.

Origin of Magnetite Crystals in Martian Meteorite ALH84001 Carbonate Disks

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K.L.; Clemett, S.J.; McKay, D.S.; Gibson, E. K.; Wentworth, S. J.

2010-01-01

Martian meteorite ALH84001 preserves evidence of interaction with aqueous fluids while on Mars in the form of microscopic carbonate disks which are believed to have precipitated approx.3.9 Ga ago at beginning of the Noachian epoch. Intimately associated within and throughout these carbonate disks are nanocrystal magnetites (Fe3O4) with unusual chemical and physical properties, whose origins have become the source of considerable debate. One group of hypotheses argues that these Fe3O4 are the product of partial thermal decomposition of the host carbonate. Alternatively, the origins of Fe3O4 and carbonate may be unrelated; that is, from the perspective of the carbonate the magnetite is allochthonous. We have sought to resolve between these hypotheses through the detailed characterized of the compositional and structural relationships of the carbonate disks and associated magnetites with the orthopyroxene matrix in which they are embedded [1]. We focus this discussion on the composition of ALH84001 magnetites and then compare these observations with those from our thermal decomposition studies of sideritic carbonates under a range of plausible geological heating scenarios.

A Case of Intractable Hemophagocytic Syndrome Associated with Systemic Lupus Erythematosus Resistant to Corticosteroids and Intravenous Cyclophosphamide that Was Successfully Treated with Cyclosporine A.

PubMed

Toko, Hirofumi; Tsuboi, Hiroto; Umeda, Naoto; Honda, Fumika; Ohyama, Ayako; Takahashi, Hidenori; Abe, Saori; Yokosawa, Masahiro; Asashima, Hiromitsu; Hagiwara, Shinya; Hirota, Tomoya; Kondo, Yuya; Matsumoto, Isao; Sumida, Takayuki

2018-05-18

Hemophagocytic syndrome (HPS) associated with systemic lupus erythematosus (SLE), dubbed acute lupus hemophagocytic syndrome (ALHS), is an intractable complication of SLE. A 24-year-old man who had been diagnosed with SLE three months previously, presented with fever, rash, hallucination, and pancytopenia accompanied with hyperferritinemia and bone marrow hemophagocytosis. He was diagnosed with ALHS and neuropsychiatric (NP)-SLE. Although 4 courses of methylprednisolone pulse therapy and 1 course of intravenous cyclophosphamide (IVCY) improved his NP-SLE, his ALHS did not respond. However, the addition of cyclosporine A (CsA) led to a rapid remission from ALHS. This suggests the usefulness of CsA in the treatment of intractable, corticosteroid- and IVCY-resistant ALHS.

Estimation of Mesoscale Atmospheric Latent Heating Profiles from TRMM Rain Statistics Utilizing a Simple One-Dimensional Model

NASA Technical Reports Server (NTRS)

Iacovazzi, Robert A., Jr.; Prabhakara, C.

2002-01-01

In this study, a model is developed to estimate mesoscale-resolution atmospheric latent heating (ALH) profiles. It utilizes rain statistics deduced from Tropical Rainfall Measuring Mission (TRMM) data, and cloud vertical velocity profiles and regional surface thermodynamic climatologies derived from other available data sources. From several rain events observed over tropical ocean and land, ALH profiles retrieved by this model in convective rain regions reveal strong warming throughout most of the troposphere, while in stratiform rain regions they usually show slight cooling below the freezing level and significant warming above. The mesoscale-average, or total, ALH profiles reveal a dominant stratiform character, because stratiform rain areas are usually much larger than convective rain areas. Sensitivity tests of the model show that total ALH at a given tropospheric level varies by less than +/- 10 % when convective and stratiform rain rates and mesoscale fractional rain areas are perturbed individually by +/- 15 %. This is also found when the non-uniform convective vertical velocity profiles are replaced by one that is uniform. Larger variability of the total ALH profiles arises when climatological ocean- and land-surface temperatures (water vapor mixing ratios) are independently perturbed by +/- 1.0 K (+/- 5%) and +/- 5.0 K (+/- 15%), respectively. At a given tropospheric level, such perturbations can cause a +/- 25% variation of total ALH over ocean, and a factor-of-two sensitivity over land. This sensitivity is reduced substantially if perturbations of surface thermodynamic variables do not change surface relative humidity, or are not extended throughout the entire model evaporation layer. The ALH profiles retrieved in this study agree qualitatively with tropical total diabatic heating profiles deduced in earlier studies. Also, from January and July 1999 ALH-profile climatologies generated separately with TRMM Microwave Imager and Precipitation Radar rain statistics, it is shown that ALH profiles can be retrieved utilizing diverse satellite-derived rain products that offer convective and stratiform discrimination. Therefore, the ALH retrieval model developed in this study can be used to make regional estimates of total diabatic heating profiles in the future Global Precipitation Measurement mission, and to assimilate these profiles into numerical weather forecast and climate models.

Estimation of Mesoscale Atmospheric Latent Heating Profiles from TRMM Rain Statistics Utilizing a Simple One-Dimensional Model

NASA Technical Reports Server (NTRS)

Iacovazzi, Robert A., Jr.; Prabhakara, C.; Lau, William K. M. (Technical Monitor)

2001-01-01

In this study, a model is developed to estimate mesoscale-resolution atmospheric latent heating (ALH) profiles. It utilizes rain statistics deduced from Tropical Rainfall Measuring Mission (TRMM) data, and cloud vertical velocity profiles and regional surface thermodynamic climatologies derived from other available data sources. From several rain events observed over tropical ocean and land, ALH profiles retrieved by this model in convective rain regions reveal strong warming throughout most of the troposphere, while in stratiform rain regions they usually show slight cooling below the freezing level and significant warming above. The mesoscale-average, or total, ALH profiles reveal a dominant stratiform character, because stratiform rain areas are usually much larger than convective rain areas. Sensitivity tests of the model show that total ALH at a given tropospheric level varies by less than +/- 10 % when convective and stratiform rain rates and mesoscale fractional rain areas are perturbed individually by 1 15 %. This is also found when the non-uniform convective vertical velocity profiles are replaced by one that is uniform. Larger variability of the total ALH profiles arises when climatological ocean- and land-surface temperatures (water vapor mixing ratios) are independently perturbed by +/- 1.0 K (+/- 5 %) and +/- 5.0 K (+/- 15 %), respectively. At a given tropospheric level, such perturbations can cause a +/- 25 % variation of total ALH over ocean, and a factor-of-two sensitivity over land. This sensitivity is reduced substantially if perturbations of surface thermodynamic variables do not change surface relative humidity, or are not extended throughout the entire model evaporation layer. The ALH profiles retrieved in this study agree qualitatively with tropical total diabatic heating profiles deduced in earlier studies. Also, from January and July 1999 ALH-profile climatologies generated separately with TRMM Microwave Imager and Precipitation Radar rain statistics, it is shown that ALH profiles can be retrieved utilizing diverse satellite-derived rain products that offer convective and stratiform discrimination. Therefore, the ALH retrieval model developed in this study can be used to make regional estimates of total diabatic heating profiles in the future Global Precipitation Measurement mission, and to assimilate these profiles into numerical weather forecast and climate models.

Analysis of Siderite Thermal Decomposition by Differential Scanning Calorimetry

NASA Technical Reports Server (NTRS)

Bell, M. S.; Lin, I.-C.; McKay, D. S.

2000-01-01

Characterization of carbonate devolitilization has important implications for atmospheric interactions and climatic effects related to large meteorite impacts in platform sediments. On a smaller scale, meteorites contain carbonates which have witnessed shock metamorphic events and may record pressure/temperature histories of impact(s). ALH84001 meteorite contains zoned Ca-Mg-Fe-carbonates which formed on Mars. Magnetite crystals are found in the rims and cores of these carbonates and some are associated with void spaces leading to the suggestion by Brearley et al. that the crystals were produced by thermal decomposition of the carbonate at high temperature, possibly by incipient shock melting or devolitilization. Golden et al. recently synthesized spherical Mg-Fe-Ca-carbonates from solution under mild hydrothermal conditions that have similar carbonate compositional zoning to those of ALH84001. They have shown experimental evidence that the carbonate-sulfide-magnetite assemblage in ALH84001 can result from a multistep inorganic process involving heating possibly due to shock events. Experimental shock studies on calcium carbonate prove its stability to approx. 60 GPa, well in excess of the approx. 45 GPa peak pressures indicated by other shock features in ALH84001. In addition, Raman spectroscopy of carbonate globules in ALH84001 indicates no presence of CaO and MgO. Such oxide phases should be found associated with the magnetites in voids if these magnetites are high temperature shock products, the voids resulting from devolitilization of CO2 from calcium or magnesium carbonate. However, if the starting material was siderite (FeCO3), thermal breakdown of the ALH84001 carbonate at 470 C would produce iron oxide + CO2. As no documentation of shock effects in siderite exists, we have begun shock experiments to determine whether or not magnetite is produced by the decomposition of siderite within the < 45GPa pressure window and by the resultant thermal pulse to approx. 600 C experienced by ALH84001. Here, we report thermal and compositional characterization of unshocked siderite and its transition to magnetite. Additional information is contained in the original extended abstract.

Geochemical evidence for mixing of three components in martian orthopyroxenite ALH 84001. [Abstract only

NASA Technical Reports Server (NTRS)

Mittlefehldt, D. W.; Lindstrom, M. M.

1994-01-01

ALH 84001, a ferroan martian orthopyroxenite, originally consisted of three petrographically defined components: a cumulus assemblage of orthopyroxene + chromite, a trapped melt assemblage of orthopyroxene(?) + chromite + maskelynite + apatite + augite +/- pyrite, and a metasomatic assemblage of carbonate +/- pyrite. We present the results of Instrumental Neutron Activation Analysis (INAA) study of five bulk samples of ALH 84001, combined with Scanning Ion Mass Spectrometer (SIMS) data on the orthopyroxene, in order to attempt to set limits on the geochemical characteristics of the latter two components, and therefore on the petrogenesis of ALH 84001. The INAA data support the petrographic observations, suggesting that there are at least three components in ALH 84001. We will assume that each of the three geochemically required components can be equated with one of the petrographically observed components. Both trapped melt and metasomatic components in ALH 84001 have higher Na than orthopyroxene based on compositions of maskelynite, apatite, and carbonate. For the metasomatic component, we will assume its Na content is that of carbonate, while for a trapped melt component, we will use a typical Na content inferred for martian meteorite parent melts, approximately 1 wt% Na2O. Under these assumptions, we can set limits on the Light Rare Earth Elements/Heavy Rare Earth Elements (LREE/HREE) ratios of the components, and use this information to compare the petrogenesis of ALH 84001 with other martian meteorites. The above calculations assume that the bulk samples are representative of different portions of ALH 84001. We will also evaluate the possible heterogeneous distribution of mineral phases in the bulk samples as the cause of compositional heterogeneity in our samples.

LEW 88180, LEW 87119, and ALH 85119: New EH6, EL7, and EL4 Enstatite Chondrites

NASA Astrophysics Data System (ADS)

Zhang, Y.; Benoit, P. H.; Sears, D. W. G.

1993-07-01

The EH and EL chondrites formed in a uniquely reducing environment, containing low-Fe pyroxene, abundant metal, and a number of unusual sulphides and other minerals [1]. An important aspect of their history is that while the EL chondrites consist predominantly of metamorphosed meteorites, the EH consist primarily of little-metamorphosed meteorites (e.g., [2]), and yet EL chondrites have lower equilibrium temperatures than EH chondrite [3,4]. To help understand this observation and its implication for the history of the classes, we have been searching for new enstatite chondrites, looking especially for meteorites of previously unknown chemical-petrologic class. Using our normal INAA methods [5] and sample splits of 100-200 mg, the bulk composition of nine Antarctic enstatite chondrites and one fall were determined. The data were used to assign the meteorites to chemical classes, the Ni/Ir vs. Al/V plot (Fig. 1) being especially useful since it uses the refractory element difference between EH and EL chondrites and is insensitive to metal-silicate heterogeneity. The well-analyzed Qingzhen was included to check our method. ALH84170, ALH84206, and EET87746, which Mason described as E3, E4, and E4 were all found to be EH chondrites [6]. Our data for the three paired EL3 chondrites were discussed earlier (MAC88136, 88180, and 88184) [7,8]. LEW88180, LEW87119, and ALH85119, which Mason described as type E6, E6, and E4 respectively [6], are EH, EL, and EL; thus LEW88180 and ALH85119 appear to be the first EH6 and EL4 chondrites. The compositions of kamacite, phosphide, and niningerite-alabandite (Fig. 2) for ALH84170, ALH84206, EET87746, LEW88180, and ALH85119 are consistent with Mason's petrologic type assignments [6]. The mineral composition of LEW88180 (2.7% Si and 9.4% Ni in the kamacite, 7.8% Ni in the phosphide, and 60% FeS in the niningerite) confirms our classification of this meteorite as EH6. ALH85119 contains kamacite with 0.5% Si and 7% Ni, phosphide with 46% Ni and alabandite with 22% FeS, confirming its classification as the first EL4 chondrite. The LEW87119 meteorite has kamacite with 1.5% Si and 9.1% Ni, troilite with 2.9% Cr and 0.64% Ti, and alabandite with the highest FeS (49%) recorded for EL chondrites. Since the meteorite does not appear to be shocked or impact melted (it has medium-grained texture with the slightest indication of chondrules and normal metal and sulfide distribution) and the phase chemistry clearly indicates a higher equilibration temperature than the EL6 chondrites, for the time being we propose to call LEW87119 an EL7 chondrite. With the discovery in the last decade or so of a number of low-petrologic-type EH chondrites and the present discovery of EH6 and EL7 chondrites, the EH class and the EL class now appear to be comparable in their range of mineral compositions and thereby equilibration temperatures. The highest equilibration temperature for the EL chondrites is now ~700 degrees C, which is close to that of EH6 chondrite (Fig. 2). Equilibration temperatures for the EL6 chondrites are similar to those of EH4 chondrites. It may be that EH and EL classes have more similar thermal histories than previously supposed and that it is purely the textures of the two classes that are widely different and in need of further research. References: [1] Keil K. (1968) JGR, 73, 6945-6976. [2] Sears D. W. G. and Weeks K. S. (1984) Nature, 308, 257-259. [3] Skinner B. J. and Luce F. D. (1971) Amer. Min., 56, 1269-1296. [4] Zhang Y. et al. (1992) Meteoritics, 27, 310-311. [5] Weeks K. S.and Sears D. W. G. (1985) GCA, 49, 1525-1536. [6] Mason in Antarctic Meteorite Newsletter (1986, 1987, 1989, and 1990) 9(3), 10(2), 12(1,3), and 13(2,3). [7] Lin Y. T. et al. (1991) LPSC XXII, 811-812. [8] Chang Y. et al. (1992) LPSC XXIII, 217-218.

Microstructures of Hibonite From an ALH A77307 (CO3.0) CAI: Evidence for Evaporative Loss of Calcium

NASA Technical Reports Server (NTRS)

Han, Jangmi; Brearley, Adrian J.; Keller, Lindsay P.

2014-01-01

Hibonite is a comparatively rare, primary phase found in some CAIs from different chondrite groups and is also common in Wark-Lovering rims [1]. Hibonite is predicted to be one of the earliest refractory phases to form by equilibrium condensation from a cooling gas of solar composition [2] and, therefore, can be a potential recorder of very early solar system processes. In this study, we describe the microstructures of hibonite from one CAI in ALH A77307 (CO3.0) using FIB/TEM techniques in order to reconstruct its formational history.

Allan Hills 76005 Polymict Eucrite Pairing Group: Curatorial and Scientific Update on a Jointly Curated Meteorite

NASA Technical Reports Server (NTRS)

Righter, K.

2011-01-01

Allan Hills 76005 (or 765) was collected by the joint US-Japan field search for meteorites in 1976-77. It was described in detail as "pale gray in color and consists of finely divided macrocrystalline pyroxene-rich matrix that contains abundant clastic fragments: (1) Clasts of white, plagioclase-rich rocks. (2) Medium-gray, partly devitrified, cryptocrystalline. (3) Monomineralic fragments and grains of pyroxene, plagioclases, oxide minerals, sulfides, and metal. In overall appearance it is very similar to some lunar breccias." Subsequent studies found a great diversity of basaltic clast textures and compositions, and therefore it is best classified as a polymict eucrite. Samples from the 1976-77, 77-78, and 78-79 field seasons (76, 77, and 78 prefixes) were split between US and Japan (NIPR). The US specimens are currently at NASA-JSC, Smithsonian Institution, or the Field Museum in Chicago. After this initial finding of ALH 76005, the next year s team recovered one additional mass ALH 77302, and then four additional masses were found during the third season ALH 78040 and ALH 78132, 78158 and 78165. The joint US-Japan collection effort ended after three years and the US began collecting in the Trans-Antarctic Mountains with the 1979-80 and subsequent field seasons. ALH 79017 and ALH 80102 were recovered in these first two years, and then in 1981-82 field season, 6 additional masses were recovered from the Allan Hills. Of course it took some time to establish pairing of all of these specimens, but altogether the samples comprise 4292.4 g of material. Here will be summarized the scientific findings as well as some curatorial details of how specimens have been subdivided and allocated for study. A detailed summary is also presented on the NASA-JSC curation webpage for the HED meteorite compendium.

ARC-1996-AC96-0345-11

NASA Image and Video Library

1996-10-10

Martian Meteorite (ALH84001): This high resolution transmission electron microscope image is of a cast, or replica, from a chip of a Martian meteorite, labeled ALH84001, that shows the outline of what are believed to be possible microscopic fossils of bacteria-like organisms that may have lived on Mars more than 3.6 billion years ago. The tubular features in this image are less than a micrometer in size, or about 1/500th the diameter of a human hair. (JSC ref: S96-12637)

Using Real-Time PCR to Quantify Aster Yellows Phytoplasma in its Insect Vector; Relationship of Infectivity to Transmissibility in the Aster Leafhopper

USDA-ARS?s Scientific Manuscript database

The aster yellows (AY) index is used to prescribe insecticide sprays that target Macrosteles quadrilineatus, or aster leafhopper (ALH), the vector of the aster yellows phytoplasma (AYp). The AY index metric is the product of the proportion of infective ALHs and the relative ALH population size at a ...

Modeling of a thermal energy storage system based on coupled metal hydrides (magnesium iron – sodium alanate) for concentrating solar power plants

DOE PAGES

d'Entremont, A.; Corgnale, C.; Sulic, M.; ...

2017-08-31

Concentrating solar power plants represent low cost and efficient solutions for renewable electricity production only if adequate thermal energy storage systems are included. Metal hydride thermal energy storage systems have demonstrated the potential to achieve very high volumetric energy densities, high exergetic efficiencies, and low costs. The current work analyzes the technical feasibility and the performance of a storage system based on the high temperature Mg 2FeH 6 hydride coupled with the low temperature Na 3AlH 6 hydride. To accomplish this, a detailed transport model has been set up and the coupled metal hydride system has been simulated based onmore » a laboratory scale experimental configuration. Proper kinetics expressions have been developed and included in the model to replicate the absorption and desorption process in the high temperature and low temperature hydride materials. The system showed adequate hydrogen transfer between the two metal hydrides, with almost complete charging and discharging, during both thermal energy storage and thermal energy release. The system operating temperatures varied from 450°C to 500°C, with hydrogen pressures between 30 bar and 70 bar. This makes the thermal energy storage system a suitable candidate for pairing with a solar driven steam power plant. The model results, obtained for the selected experimental configuration, showed an actual thermal energy storage system volumetric energy density of about 132 kWh/m 3, which is more than 5 times the U.S. Department of Energy SunShot target (25 kWh/m 3).« less

Modeling of a thermal energy storage system based on coupled metal hydrides (magnesium iron – sodium alanate) for concentrating solar power plants

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

d'Entremont, A.; Corgnale, C.; Sulic, M.

Concentrating solar power plants represent low cost and efficient solutions for renewable electricity production only if adequate thermal energy storage systems are included. Metal hydride thermal energy storage systems have demonstrated the potential to achieve very high volumetric energy densities, high exergetic efficiencies, and low costs. The current work analyzes the technical feasibility and the performance of a storage system based on the high temperature Mg 2FeH 6 hydride coupled with the low temperature Na 3AlH 6 hydride. To accomplish this, a detailed transport model has been set up and the coupled metal hydride system has been simulated based onmore » a laboratory scale experimental configuration. Proper kinetics expressions have been developed and included in the model to replicate the absorption and desorption process in the high temperature and low temperature hydride materials. The system showed adequate hydrogen transfer between the two metal hydrides, with almost complete charging and discharging, during both thermal energy storage and thermal energy release. The system operating temperatures varied from 450°C to 500°C, with hydrogen pressures between 30 bar and 70 bar. This makes the thermal energy storage system a suitable candidate for pairing with a solar driven steam power plant. The model results, obtained for the selected experimental configuration, showed an actual thermal energy storage system volumetric energy density of about 132 kWh/m 3, which is more than 5 times the U.S. Department of Energy SunShot target (25 kWh/m 3).« less

A Pilot Study of the Efficacy of Active Leptospermum Honey for the Treatment of Partial-Thickness Facial Burns.

PubMed

Duncan, Christina L; Enlow, Paul T; Szabo, Margo M; Tolchin, Eric; Kelly, Robert W; Castanon, Lourdes; Aballay, Ariel M

2016-08-01

Research suggests that active Leptospermum honey (ALH) improves outcomes in patients with partial-thickness burns by enhancing healing and reepithelialization rates, as well as by protecting against antibiotic-resistant microorganisms. This study assessed the effectiveness of ALH gel on healing time, bacterial growth, patient satisfaction, and cost of treatment. Single-arm, prospective case series. Seven patients (aged 7-64 years) with partial-thickness facial burns were recruited from a northeastern US burn center. All patients cleansed their wounds daily with soap and water, after which they applied ALH gel. Three physicians independently rated healing using wound photography and daily tests for the presence of exudate. Wound cultures on days 1 and 7 (±2 days) assessed bacterial growth. Patients completed a satisfaction survey at the end of treatment, and cost of treatment was calculated. Healing time ranged from 3 to 14 days (mean, 8.1 days). Wound cultures revealed normal bacterial growth on days 1 and 7 for all patients. Patients rated ALH gel favorably, with the most common complaint of stickiness in 5 patients. One patient experienced transient burning on application that did not interrupt treatment. Average hospital-based cost of treatment was $26.15 per patient. Healing time was congruent with or better than what would have been expected with standard treatment. Furthermore, despite no antibiotic treatment, wound culture results yielded no abnormal bacterial growth. Finally, patients overall reported satisfaction with treatment. The findings of this study suggest that ALH is a clinically and economically valuable treatment for partial-thickness facial burns.

The Origin of Magnetite Crystals in ALH84001 Carbonate Disks

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K. L.; Clemett, S. J.; Wentworth, S. J.; McKay, D. S.; Gibson, E. K., Jr.

2012-01-01

Martian meteorite ALH84001 preserves evidence of interaction with aqueous fluids while on Mars in the form of microscopic carbonate disks believed to have formed approx 3.9 Ga ago at beginning of the Noachian epoch. Intimately associated within and throughout these carbonate disks are nanocrystal magnetites (Fe3O4) with unusual chemical and physical properties, whose origins have become the source of considerable debate. One group of hypotheses argues that these magnetites are the product of partial thermal decomposition of the host carbonate. Alternatively, the origins of magnetite and carbonate may be unrelated; that is, from the perspective of the carbonate the magnetite is allochthonous. We have sought to resolve between these hypotheses through the detailed characterized of the compositional and structural relationships between the carbonate disks, their associated magnetites and the orthopyroxene matrix in which they are embedded. Comparison of these results with experimental thermal decomposition studies of sideritic carbonates conducted under a range of heating scenarios suggests that the magnetite nanocrystals in the ALH84001 carbonate disks are not the products of thermal decomposition.

New Insights into the Origin of Magnetite Crystals in ALH84001 Carbonate Disks

NASA Technical Reports Server (NTRS)

Thomas-Keptra, Katie L.; Clemett, S. J.; Wentworth S. J.; Mckay, D. S.; Gibson, E. K., Jr.

2010-01-01

Martian meteorite ALH84001 preserves evidence of interaction with aqueous fluids while on Mars in the form of microscopic carbonate disks believed to have formed approx.3.9 Ga ago at beginning of the Noachian epoch. Intimately associated within and throughout these carbonate disks are nanocrystal magnetites (Fe3O4) with unusual chemical and physical properties, whose ori gins have become the source of considerable debate. One group of hypotheses argues that these magnetites are the product of partial thermal decomposition of the host carbonate. Alternatively, the origins of magnetite and carbonate may be unrelated: that is, from the perspective of the carbonate the magnetite is allochthonous. We have sought to resolve between these hypotheses through the detailed characterized of the compositional and structural relationships between the carbonate disks, their associated magnetites and the orthopyroxene matrix in which they are embedded [1]. Comparison of these results with experimental thermal decomposition studies of sideritic carbonates conducted under a range of heating scenarios suggests that the magnetite nanocrystals in the ALH84001 carbonate disks are not the products of thermal decomposition.

Understanding the premalignant potential of atypical hyperplasia through its natural history: A longitudinal cohort study

PubMed Central

Hartmann, Lynn C; Radisky, Derek C; Frost, Marlene H; Santen, Richard J; Vierkant, Robert A; Benetti, Lorelle L; Tarabishy, Yaman; Ghosh, Karthik; Visscher, Daniel W; Degnim, Amy C

2014-01-01

Atypical hyperplasia is a high risk premalignant lesion of the breast, but its biology is poorly understood. Many believe that atypical ductal hyperplasia (ADH) is a direct precursor for low-grade ductal breast cancer (BC) while atypical lobular hyperplasia (ALH) serves as a risk indicator. These assumptions underlie current clinical recommendations. We tested these assumptions by studying the characteristics of the breast cancers (BCs) that develop in women with ADH or ALH. Using the Mayo Benign Breast Disease Cohort, we identified all women with ADH or ALH from 1967–2001 and followed them for later BCs, characterizing side of BC vs side of atypia; time to BC; type, histology and grade of BC, looking for patterns consistent with precursors vs risk indicators. 698 women with atypical hyperplasia were followed a mean of 12.5 years; 143 developed BC. For both ADH and ALH, there is a 2:1 ratio of ipsilateral to contralateral BCs. The ipsilateral predominance is marked in the first five years, consistent with a precursor phenotype for both ADH and ALH. For both, there is a predominance of invasive ductal cancers with 69% of moderate or high-grade. 25% are node positive. Both ADH and ALH portend risk for DCIS and invasive BCs, predominantly ductal, with two thirds moderate or high-grade. The ipsilateral breast is at especially high risk for BC in the first five years after atypia, with risk remaining elevated in both breasts long-term. ADH and ALH behave similarly in terms of later BC endpoints. PMID:24480577

Safety and efficacy of active Leptospermum honey in neonatal and paediatric wound debridement.

PubMed

Amaya, R

2015-03-01

Safety is a critically important factor in the selection of products used in neonatal and paediatric wound care. Given the lack of standardisation of neonatal and paediatric wound care protocols, the goal of this study was to present data on the safety and efficacy of active Leptospermum honey (ALH) in this patient population. A multicentre, retrospective chart review was conducted at eight inpatient facilities and one outpatient clinic between October 2011 and March 2014. The number of applications of ALH, adverse events, and the success of debridement and wound healing were recorded. Data were collected on 115 neonatal and paediatric patients, with 121 wounds requiring debridement, treated with ALH. Patients were treated for an average of 18.7 days. ALH was well tolerated, with two (1.7%) patients reporting adverse events involving a transient stinging sensation on application, which did not prohibit additional applications of ALH. Successful debridement was achieved in 86.0% (104 wounds), and 77.7% (94 wounds) were successfully closed using nonsurgical intervention. Outcomes in neonates were similar to the overall paediatric population, with 86.1% (31/36) wounds successfully debrided with no adverse events. In a subset of six patients with available pre- and post-treatment data, no clinically meaningful changes in white blood cell counts or glucose levels were associated with the initiation of treatment with ALH. The results of this study support ALH as a safe and effective treatment option in this group of patients. This study was supported by a grant from Derma Sciences (Princeton, NJ USA). Dr Amaya is a paid speaker for Derma Sciences.

Successful management of angiolymphoid hyperplasia with eosinophilia in a split-face trial of topical tacrolimus and timolol solution.

PubMed

Chacon, Anna; Mercer, Jessica

2016-08-01

Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon, benign condition characterized by multiple benign angiomatous nodules or plaques. Cutaneous lesions can be painful, pruritic, pulsatile, or potentially disfiguring resulting in significant morbidity. ALHE is a pathologic diagnosis featuring proliferations of capillary-sized vessels with epithelioid endothelial cells surrounded by larger, thick-walled vessels and accompanying eosinophils and lymphocytes. Surgery is generally required, however the skin lesions often recur after excision. ALHE is notoriously difficult to treat and many physicians would prefer a non-invasive treatment of choice. We report a case of ALHE that was successfully treated with the novel use of topical tacrolimus in a split-face trial with topical timolol solution.

Efficacy of horse chestnut leaf extract ALH-L1005 as a matrix metalloproteinase inhibitor in ligature-induced periodontitis in canine model

PubMed Central

Kim, Se Eun; Kim, Tae Hyun; Park, Shin Ae; Kim, Won Tae; Park, Young Woo; Ahn, Jae Sang; Jeong, Manbok; Kim, Min-Young

2017-01-01

Matrix metalloproteinases (MMPs) are the main proteinases associated with periodontal tissue destruction and remodeling. Therefore, inhibition of host-derived MMPs has a key role in the prevention and reduction of periodontitis progression. Horse chestnut (Aesculus hippocastanum L.) extracts have been used as treatments for inflammatory disease, traditionally. This study assessed the clinical effect as a MMP inhibitor of horse chestnut leaf extract ALH-L1005 on periodontitis. ALH-L1005 was obtained from horse chestnut leaf and its MMP inhibitory activities estimated. Periodontitis was induced in beagles assigned to 4 groups and medicated for 6 weeks: low dose test (LT; ALH-L1005, 100 mg/kg/day), high dose test (HT; ALH-L1005, 200 mg/kg/day), positive control (PC; doxycycline, 10 mg/kg/day), or negative control (NC; placebo). Before and after administration, clinical indices of the teeth and MMP quantity in gingival tissues using zymography were measured. Clinical conditions of the LT, HT, and PC groups were significantly improved after 6 weeks. In zymographic evaluations, gelatinolytic and caseinolytic activities were suppressed in LT, HT, and PC groups but not in the NC group. The results suggest that ALH-L1005 could be an effective agent for clinical prevention and treatment of periodontitis by inhibiting the gelatinase and collagenase activities, which can detach periodontal ligaments from alveolar bone. PMID:27515267

Efficacy of horse chestnut leaf extract ALH-L1005 as a matrix metalloproteinase inhibitor in ligature-induced periodontitis in canine model.

PubMed

Kim, Se Eun; Kim, Tae Hyun; Park, Shin Ae; Kim, Won Tae; Park, Young Woo; Ahn, Jae Sang; Jeong, Manbok; Kim, Min-Young; Seo, Kangmoon

2017-06-30

Matrix metalloproteinases (MMPs) are the main proteinases associated with periodontal tissue destruction and remodeling. Therefore, inhibition of host-derived MMPs has a key role in the prevention and reduction of periodontitis progression. Horse chestnut ( Aesculus hippocastanum L.) extracts have been used as treatments for inflammatory disease, traditionally. This study assessed the clinical effect as a MMP inhibitor of horse chestnut leaf extract ALH-L1005 on periodontitis. ALH-L1005 was obtained from horse chestnut leaf and its MMP inhibitory activities estimated. Periodontitis was induced in beagles assigned to 4 groups and medicated for 6 weeks: low dose test (LT; ALH-L1005, 100 mg/kg/day), high dose test (HT; ALH-L1005, 200 mg/kg/day), positive control (PC; doxycycline, 10 mg/kg/day), or negative control (NC; placebo). Before and after administration, clinical indices of the teeth and MMP quantity in gingival tissues using zymography were measured. Clinical conditions of the LT, HT, and PC groups were significantly improved after 6 weeks. In zymographic evaluations, gelatinolytic and caseinolytic activities were suppressed in LT, HT, and PC groups but not in the NC group. The results suggest that ALH-L1005 could be an effective agent for clinical prevention and treatment of periodontitis by inhibiting the gelatinase and collagenase activities, which can detach periodontal ligaments from alveolar bone.

Reconstruction of the Exposure Histories of 20 Allan Hills Ordinary Chondrites on the Basis of Cosmogenic 10Be, 26Al, Noble Gases, and Cosmic Ray Tracks

NASA Astrophysics Data System (ADS)

Neupert, U.; Knauer, M.; Michel, R.; Loeken, Th.; Schultz, L.; Dittrich-Hannen, B.; Suter, M.; Kubik, P. W.; Metzler, K.; Romstedt, J.

1995-09-01

Twenty ordinary chondrites from the 1988/89 meteorite search (ALH 88004, 88008, 88010, 88011, 88013, 88016 to 88021, 88026 to 88031, 88033, 88039, 88042) [1,2] were investigated for 10Be and 26Al, and for He, Ne and Ar by accelerator and rare gas mass spectrometry, respectively. Cosmic ray tracks were measured in samples of ALH 88019. Using theoretical production rates calculated by a physical model [3] the experimental data are interpreted with respect to the reconstruction of the preatmospheric exposure conditions and exposure histories of the meteoroids. Ordinary chondrites are particularly well suited to exemplify the capabilities of an interpretation of many cosmogenic nuclides measured in one sample. Model calculations of GCR production rates were performed for 10Be, 26Al, 3He, 21Ne, 22Ne and 38Ar as reported elsewhere [4,5]. For all meteorites, except for ALH 88019, the cosmogenic nuclide data can be explained by simple one stage exposure histories between 3 Ma and 44 Ma in meteoroids with radii between 5 cm and 85 cm. Exposure ages were derived from cosmogenic 3He, 21Ne and 38Ar on the basis of the theoretical production rates as function of3He/21Ne and 22Ne/21Ne as well as on the empirical ones proposed by Eugster [6]. The average ratios of exposure ages determined from theoretical production rates to those calculated according to Eugster [6] were 1.08+/-0.11, 1.11+/-0.25 and 1.12+/-0.17 in case of 3He, 21Ne and 38Ar, respectively. Repeated measurements of 10Be and 26Al in ALH 88019 resulted in 10.4+/-1.3 dpm/kg and 5.6+/-0.5 dpm/kg, respectively. But, the cosmogenic rare gas concentrations point to a (single stage) exposure age of 39 Ma in a meteoroid. This is in accordance with a measured cosmic ray track density in olivine of 2.8 * 10^6 cm^-2. The samples are from depths betwen 3 cm and 8 cm. Based on the track data we obtain a minimum meteoroid radius of 8 cm. The low 10Be and 26Al cannot be explained by a one stage exposure history and a long terrestrial age. Possible other exposure scenarios are discussed. Using the theoretical 10Be production rates and the 3He/21Ne and 22Ne/21Ne ratios, constraints about the sizes of the meteoroids and about the shielding depths in the samples were derived. 26Al was not used for this purpose since in four meteorites it is evidently affected by SCR production and since, generally, it could be changed due to long terrestrial residence times. However, most of the observed 26Al concentrations which are not affected by SCR production are consistent within experimental uncertainties with the expected GCR production rates. Substantial terrestrial age are proposed for ALH 88008, ALH 88029 and ALH 88030. Pairing among the investigated meteorites is discussed on the basis of rare gas data, 10Be and 26Al, and NTL data by Benoit et al. [7,8]. It can be concluded that the 20 meteorites result from at least 16 different falls. Acknowledgement: This work was supported by the Deutsche Forschungsgemeinschaft and the Swiss National Science Foundation. References: [1] Meteoritical Bulletin (1990) Meteoritics, 25, 237. [2] Meteoritical Bulletin (1991) Meteoritics, 26, 68. [3] Michel R. et al. (1991) Meteoritics, 26, 221-242. [4] Michel R. et al. (1995) Planet. Space Sci., in press. [5] Herpers U. et al. (1995) Planet. Space Sci., in press. [6] Eugster O. (1988) GCA, 52, 1649-1662. [7] Benoit P. H. et al. (1991) Meteoritics, 26, 262. [8] Benoit P. H. et al. (1992) Meteoritics, 27, 110.

Thermal Decomposition of an Impure (Roxbury) Siderite: Relevance to the Presence of Chemically Pure Magnetite Crystals in ALH84001 Carbonate Disks

NASA Technical Reports Server (NTRS)

McKay, D.S.; Gibson, E.K.; Thomas-Keprta, K.L.; Clemett, S.J.; Wentworth, S.J.

2009-01-01

The question of the origin of nanophase magnetite in Martian meteorite ALH84001 has been widely debated for nearly a decade. Golden et al. have reported producing nearly chemically pure magnetite from thermal decomposition of chemically impure siderite [(Fe, Mg, Mn)CO3]. This claim is significant for three reasons: first, it has been argued that chemically pure magnetite present in the carbonate disks in Martian meteorite ALH84001 could have formed by the thermal decomposition of the impure carbonate matrix in which they are embedded; second, the chemical purity of magnetite has been previously used to identify biogenic magnetite; and, third, previous studies of thermal decomposition of impure (Mg,Ca,Mn)-siderites, which have been investigated under a wide variety of conditions by numerous researchers, invariably yields a mixed metal oxide phase as the product and not chemically pure magnetite. The explanation for this observation is that these siderites all possess the same crystallographic structure (Calcite; R3c) so solid solutions between these carbonates are readily formed and can be viewed on an atomic scale as two chemically different but structurally similar lattices.

Magnetic resonance imaging-guided core needle breast biopsies resulting in high-risk histopathologic findings: upstage frequency and lesion characteristics.

PubMed

Weinfurtner, R Jared; Patel, Bhavika; Laronga, Christine; Lee, Marie C; Falcon, Shannon L; Mooney, Blaise P; Yue, Binglin; Drukteinis, Jennifer S

2015-06-01

Analysis of magnetic resonance imaging-guided breast biopsies yielding high-risk histopathologic features at a single institution found an overall upstage rate to malignancy of 14% at surgical excision. All upstaged lesions were associated with atypical ductal hyperplasia. Flat epithelial atypia and atypical lobular hyperplasia alone or with lobular carcinoma in situ were not associated with an upstage to malignancy. The purpose of the present study w as to determine the malignancy upstage rates and imaging features of high-risk histopathologic findings resulting from magnetic resonance imaging (MRI)-guided core needle breast biopsies. These features include atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), flat epithelial atypia (FEA), and lobular carcinoma in situ (LCIS). A retrospective medical record review was performed on all MRI-guided core needle breast biopsies at a single institution from June 1, 2007 to December 1, 2013 to select biopsies yielding high-risk histopathologic findings. The patient demographics, MRI lesion characteristics, and histopathologic features at biopsy and surgical excision were analyzed. A total of 257 MRI-guided biopsies had been performed, and 50 yielded high-risk histopathologic features (19%). Biopsy site and surgical excision site correlation was confirmed in 29 of 50 cases. Four of 29 lesions (14%) were upstaged: 1 case to invasive ductal carcinoma and 3 cases to ductal carcinoma in situ. ADH alone had an overall upstage rate of 7% (1 of 14), mixed ADH/ALH a rate of 75% (3 of 4), ALH alone or with LCIS a rate of 0% (0 of 7), and FEA a rate of 0% (0 of 4). Only mixed ADH/ALH had a statistically significant upstage rate to malignancy compared with the other high-risk histopathologic subtypes combined. No specific imaging characteristics on MRI were associated with an upstage to malignancy on the statistical analysis. MRI-guided breast biopsies yielding high-risk histopathologic features were associated with an overall upstage to malignancy rate of 14% at surgical excision. All upstaged lesions were associated with ADH. FEA and ALH alone or with LCIS were not associated with an upstage to malignancy. Copyright © 2015 Elsevier Inc. All rights reserved.

Differential responses of autonomic function in sea level residents, acclimatized lowlanders at >3500 m and Himalayan high altitude natives at >3500 m: A cross-sectional study.

PubMed

Dhar, Priyanka; Sharma, Vijay K; Das, Saroj K; Barhwal, Kalpana; Hota, Sunil K; Singh, Shashi B

2018-04-09

We studied the differential responses of autonomic function in sea level residents (SLR), acclimatized lowlanders (ALH) in high altitude (HA) and HA natives (HAN) at >3500 m. Out of 771 male volunteers included in this cross-sectional study, SLR, ALH and HAN groups were comprised of 351, 307 and 113 volunteers, respectively. Our results showed persistent sympathetic dominance with significantly reduced (p < 0.05) parasympathetic response in ALH as compared to SLR and HAN populations. This may be attributed to significantly increased (p < 0.05) concentration of coronary risk factors and plasma catecholamines in ALH as compared to SLR and HAN. The ALH also showed significantly increased (p < 0.05) level of serum homocysteine as compared to SLR. The HAN exhibited no changes in autonomic function despite significantly elevated (p < 0.05) homocysteine level as compared to SLR. Our findings may have clinical relevance for assessment of susceptibility to cardiovascular risks in HA dwellers, native highlanders and patients with hypoxemia. Copyright © 2018 Elsevier B.V. All rights reserved.

Magnetotactic bacteria on Earth and on Mars.

PubMed

McKay, Christopher P; Friedmann, E Imre; Frankel, Richard B; Bazylinski, Dennis A

2003-01-01

Continued interest in the possibility of evidence for life in the ALH84001 Martian meteorite has focused on the magnetite crystals. This review is structured around three related questions: is the magnetite in ALH84001 of biological or non-biological origin, or a mixture of both? does magnetite on Earth provide insight to the plausibility of biogenic magnetite on Mars? could magnetotaxis have developed on Mars? There are credible arguments for both the biological and non-biological origin of the magnetite in ALH84001, and we suggest that more studies of ALH84001, extensive laboratory simulations of non-biological magnetite formation, as well as further studies of magnetotactic bacteria on Earth will be required to further address this question. Magnetite grains produced by bacteria could provide one of the few inorganic traces of past bacterial life on Mars that could be recovered from surface soils and sediments. If there was biogenic magnetite on Mars in sufficient abundance to leave fossil remains in the volcanic rocks of ALH84001, then it is likely that better-preserved magnetite will be found in sedimentary deposits on Mars. Deposits in ancient lakebeds could contain well-preserved chains of magnetite clearly indicating a biogenic origin.

Magnetotactic bacteria on Earth and on Mars

NASA Technical Reports Server (NTRS)

McKay, Christopher P.; Friedmann, E. Imre; Frankel, Richard B.; Bazylinski, Dennis A.

2003-01-01

Continued interest in the possibility of evidence for life in the ALH84001 Martian meteorite has focused on the magnetite crystals. This review is structured around three related questions: is the magnetite in ALH84001 of biological or non-biological origin, or a mixture of both? does magnetite on Earth provide insight to the plausibility of biogenic magnetite on Mars? could magnetotaxis have developed on Mars? There are credible arguments for both the biological and non-biological origin of the magnetite in ALH84001, and we suggest that more studies of ALH84001, extensive laboratory simulations of non-biological magnetite formation, as well as further studies of magnetotactic bacteria on Earth will be required to further address this question. Magnetite grains produced by bacteria could provide one of the few inorganic traces of past bacterial life on Mars that could be recovered from surface soils and sediments. If there was biogenic magnetite on Mars in sufficient abundance to leave fossil remains in the volcanic rocks of ALH84001, then it is likely that better-preserved magnetite will be found in sedimentary deposits on Mars. Deposits in ancient lakebeds could contain well-preserved chains of magnetite clearly indicating a biogenic origin.

House Dust Endotoxin and Peripheral Leukocyte Counts: Results from Two Large Epidemiologic Studies.

PubMed

Fessler, Michael B; Carnes, Megan U; Salo, Päivi M; Wilkerson, Jesse; Cohn, Richard D; King, Debra; Hoppin, Jane A; Sandler, Dale P; Travlos, Greg; London, Stephanie; Thorne, Peter; Zeldin, Darryl

2017-05-31

The peripheral leukocyte count is a biomarker of inflammation and is associated with human all-cause mortality. Although causes of acute leukocytosis are well-described, chronic environmental determinants of leukocyte number are less well understood. We investigated the relationship between house dust endotoxin concentration and peripheral leukocyte counts in human subjects. The endotoxin–leukocyte relationship was evaluated by linear regression in the National Health and Nutrition Examination Survey (NHANES) 2005–2006 (n=6,254) and the Agricultural Lung Health Study (ALHS; n=1,708). In the ALHS, we tested for a gene [Toll-like Receptor 4 ( TLR4 ), encoding the endotoxin receptor]-by-environment interaction in the endotoxin–leukocyte relationship using regression models with an interaction term. There is a statistically significant, positive association between endotoxin concentration and total leukocyte number [estimated change, 0.186×10 3 /μL (95% CI: 0.070, 0.301×10 3 /μL) per 10-fold change in endotoxin; p=0.004) in the NHANES. Similar positive associations were found for monocytes, lymphocytes, and neutrophils. Stratified analyses revealed possible effect modification by asthma and chronic obstructive pulmonary disease. We observed similar associations in the ALHS. For total leukocytes, there was suggestive evidence in the ALHS of a gene-by-environment interaction for minor allele carrier status at the TLR4 haplotype defined by rs4986790 and rs4986791 (interaction p=0.15). This is, to our knowledge, the first report of an association between house dust endotoxin and leukocyte count in a national survey. The finding was replicated in a farming population. Peripheral leukocyte count may be influenced by residential endotoxin exposure in diverse settings. https://doi.org/10.1289/EHP661.

A Petrographic History of Martian Meteorite ALH84001: Two Shocks and an Ancient Age

NASA Technical Reports Server (NTRS)

Treiman, Allan H.

1995-01-01

ALH84001 is an igneous meteorite, an orthopyroxenite of martian origin. It contains petrographic evidence of two shock metamorphic events, separated by thermal and chemical events. The evidence for two shock events suggests that ALH84001 is ancient and perhaps a sample of the martian highlands. From petrography and mineral chemistry, the history of ALH84001 must include: crystallization from magma, a first shock (impact) metamorphism, thermal metamorphism, low-temperature chemical alteration, and a second shock (impact) metamorphism. Originally, ALH84001 was igneous, an orthopyroxene-chromite cumulate. In the first shock event, the igneous rock was cut by melt-breccia or cataclastic veinlets, now bands of equigranular fine-grained pyroxene and other minerals (crush zones). Intact fragments of the cumulate were fractured and strained (now converted to polygonized zones). The subsequent thermal metamorphism (possibly related to the first shock) annealed the melt-breccia or cataclastic veinlets to their present granoblastic texture and permitted chemical homogenization of all mineral species present. The temperature of metamorphism was at least 875 C, based on mineral thermometers. Next, Mg-Fe-Ca carbonates and pyrite replaced plagioclase in both clasts and granular bands, producing ellipsoidal carbonate globules with sub-micron scale compositional stratigraphy, repeated identically in all globules, The second shock event produced microfault offsets of carbonate stratigraphy and other mineral contacts, radial fractures around chromite and maskelynite, and strain birefringence in pyroxene. Maskelynite could not have been preserved from the first shock event, because it would have crystallized back to plagioclase. The martian source area for ALH84001 must permit this complex, multiple impact history. Very few craters on young igneous surfaces are on or near earlier impact features. It is more likely that ALH84001 was ejected from an old igneous unit (Hesperian or Noachian age), pocked by numerous impact craters over its long exposure at the martian surface.

Early evolution of Martian volatiles: Nitrogen and noble gas components in ALH84001 and Chassigny

NASA Astrophysics Data System (ADS)

Mathew, K. J.; Marti, K.

2001-01-01

Studies on SNC meteorites have permitted the characterization of modern Martian atmospheric components as well as indigenous Martian nitrogen and solar-type xenon. New isotopic and elemental abundances of noble gases and nitrogen in ALH84001 and Chassigny provide important constraints on the early evolution of the planet. A primitive solar Xe component (Chass-S) and an evolved Xe component (Chass-E), augmented with fission Xe are identified in Chassigny. Both components represent interior reservoirs of Mars and are characterized by low 129Xe/132Xe (<1.07) and by distinct elemental ratios 36Ar/132Xe<5 and >130, respectively. Light nitrogen (δ15N=-30‰) is associated with the Chass-S component and is enriched in melt inclusions in olivine. An ancient (presumably incorporated ~4 Gyr ago) evolved Martian atmospheric component is identified in ALH84001 and has the following signatures: 129Xe/132Xe=2.16, 36Ar/38Ar>=5.0, 36Ar/132Xe=~50, 84Kr/132Xe=~6, and δ15N=7‰. The trapped Xe component in ALH84001 is not isotopically fractionated. We observe major shifts in nitrogen signatures due to cosmogenic N component in both Chassigny and ALH84001. A heavy nitrogen component of comparable magnitude (δ15N>150‰) has previously been interpreted as (heavy) Martian atmospheric N. In situ produced fission Xe components, due to 244Pu in ALH84001 and due to 238U in Chassigny, are identified. The ALH84001 data strongly constrain exchanges of Martian atmospheric and interior reservoirs. Mars retained abundant fission Xe components, and this may account for the low observed fission Xe component in the modern Martian atmosphere. Chronometric information regarding the evolution of the early Martian atmosphere can be secured from the relative abundances of radiogenic and fission Xe, as ~80% of the Martian 129Xer is observed in the atmospheric 129Xe/132Xe ratio ~ 4 Gyr ago.

ExoMol line lists XXVIII: The rovibronic spectrum of AlH

NASA Astrophysics Data System (ADS)

Yurchenko, Sergei N.; Williams, Henry; Leyland, Paul C.; Lodi, Lorenzo; Tennyson, Jonathan

2018-06-01

A new line list for AlH is produced. The WYLLoT line list spans two electronic states X 1Σ+ and A 1Π. A diabatic model is used to model the shallow potential energy curve of the A 1Π state, which has a strong pre-dissociative character with only two bound vibrational states. Both potential energy curves are empirical and were obtained by fitting to experimentally derived energies of the X 1Σ+ and A 1Π electronic states using the diatomic nuclear motion codes DPOTFIT and DUO. High temperature line lists plus partition functions and lifetimes for three isotopologues 27AlH, 27AlD and 26AlH were generated using ab initio dipole moments. The line lists cover both the X-X and A-X systems and are made available in electronic form at the CDS and ExoMol databases.

Characterization of Spitsbergen Disks by Transmission Electron Microscopy and Raman Spectroscopy

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K. L.; Clemett, S. J.; Le, L.; Ross, K.; McKay, David S.; Gibson, E. K., Jr.

2010-01-01

'Carbonate disks' found in the fractures and pores spaces of peridotite xenoliths and basalts from the island of Spitsbergen in the Norwegian Svalbard archipelago have been suggested to be "The best (and best documented) terrestrial analogs for the [Martian meteorite] ALH84001 carbonate globules ..." Previous studies have indicated that Spitsbergen carbonates show broadly comparable internal layering and mineral compositions to ALH84001 carbonate-magnetite disks. We report here for the first time, the detailed mineral characterization of Spitsbergen carbonates and their spatial relationship to the host mineral assemblages in the xenolith, using high resolution TEM (as used previously for ALH84001 carbonate disks). These studies were conducted in concert with complementary Raman and SEM analysis of the same samples. Our results indicate that there are significant chemical and physical differences between the disks in Spitsbergen and the carbonates present in ALH84001.

Risk Assessment of the Naval Postgraduate School Gigabit Network

DTIC Science & Technology

2004-09-01

Management Server (1) • Ras Server (1) • Remedy Server (1) • Samba Server(2) • SQL Servers (3) • Web Servers (3) • WINS Server (1) • Library...Server Bob Sharp INCA Windows 2000 Advanced Server NPGS Landesk SQL 2000 Alan Pires eagle Microsoft Windows 2000 Advanced Server EWS NPGS Landesk...Advanced Server Special Projects NPGS SQL Alan Pires MC01BDB Microsoft Windows 2000 Advanced Server Special Projects NPGS SQL 2000 Alan Pires

Orthopyroxenes as Recorders of Diogenite Petrogenesis: Al-Cr-Ti Systematics

NASA Astrophysics Data System (ADS)

Fowler, G. W.; Papike, J. J.; Spilde, M. N.; Shearer, C. K.

1993-07-01

This research represents a continuing effort to understand the petrogenesis of diogenites and their relationship to eucrites. Our present suite of 17 diogenites includes: Aioun El Atrouss, Ellemeet, Garland, Ibbenburen, Johnstown, Manegoan, Peckelsheim, Roda, Shalka, Tatahouine, EET 83246, EET 83247, EET 87530, EET A79002, LEW 88008, and olivine diogenites ALH 84001 and ALH A77256. In our previous studies [1,2], we reported major, minor, and trace element systematics for a subgroup of 13 of these samples. In these studies, we concluded that Fe/Mg was compromised by post-crystallization annealing reactions. We also demonstrated [1] strong, positive correlations between Cr and Al along several trajectories on a Cr-Al data display. REE and Zr-Ti systematics indicate that most sampled diogenites represent cumulates from similar basaltic melts. These modeled melt compositions are similar to eucrites but show a greater compositional range. Here we further explore the Al-Cr-Ti systematics. Figure 1 (figures include over 1,000 high quality EMP analyses) is a Ti-Al plot that shows a main trend with a positive correlation between Ti and Al. Rhoda and one of the assemblages in polymict Garland have elevated Ti concentrations relative to the main trend while Manegoan has relatively depleted Ti concentrations. Figure 2 is a (Cr+Ti) vs. Al plot with a main trend that shows a strong, positive correlation between (Cr+Ti) and Al. Manegoan occupies the high (Cr+Ti)-Al end of the trend while Peckelsheim occupies the low end. Olivine diogenite ALH A77256 falls distinctly off the trend. However, ALH 84001, our only other olivine diogenite, plots with the other diogenite in the main trend. Several things are indicated by these systematics. The positive correlation of (Cr+Ti) vs. Al indicate that the most important charge balance couples are ^VITi^4+-^IVAl(sub)2, ^VITi^3+-^IVAl, ^VICr^3+-^IVAl, and ^VIAl-^IVAl. The ^VIAl-^IVAl couple is relatively more important in olivine diogenite ALH A77256, which accounts for its data plotting below the main trend. It should be noted that the main trend and the ALH A77256 trend have less scatter near the bottom of the data arrays than near the top. In fact, lines drawn through the bottom of the arrays project through the origin. Some of the reason for the scatter, other than subsolidus annealing effects [3], may be the result of different Ti^3+/Ti^4+ ratios in OPX resulting from variable fO2 environments. A possible charge balance equation, for other then quadrilateral components is: ^VITi^3++2^VITi^4++^VICr^3++^VIAl^3+=^IVAl (Na is so low it can be ignored). The cores of most OPX grains probably still retain their igneous signatures; therefore, the high Al, Cr, Ti end of the main trend likely reflects melt compositions enriched in these elements. Acknowledgment. This research was supported by NASA Grant NAGW- 3347 and the Institute of Meteoritics. References. [1] Papike J. J. et. al. (1993) LPS XXIV, 1109-1110. [2] Shearer C. K. et al. (1993) LPS XXIV, 1289-1290. [3] Papike J. J. and Spilde M. N. (1993) This volume. Fig. 1, which appears here in the hard copy, shows Al vs. Ti atoms per formula unit. Fig. 2, which appears here in the hard copy, shows Ti + Cr vs. Al in atoms per formula unit.

Astronaut Alan B. Shepard has his blood pressure and temperature checked

NASA Technical Reports Server (NTRS)

1961-01-01

Astronaut Alan B. Shepard has his blood pressure and temperate checked prior to his Mercury-Redstone 3 (MR-3) mission, the first American manned space flight. The attending physician is Dr. William K. Douglas.

Peering Through a Martian Veil: ALHA84001 Sm-Nd Age Revisited

NASA Technical Reports Server (NTRS)

Nyquist, Laurence E.; Shih, Chi-Yu

2013-01-01

The ancient Martian orthopyroxenite ALH84001experienced a complex history of impact and aqueous alteration events. Here we summarize Sm-147-Nd-143 and Sm-146-Nd-142 analyses performed at JSC. Further, using REE data, we model the REE abundance pattern of the basaltic magma parental to ALH84001 cumulus orthopyroxene. We find the Sm-146-Nd-142 isotopic data to be consistent with isotopic evolution in material having the modeled Sm/Nd ratio from a time very close to the planet's formation to igneous crystallization of ALH84001 as inferred from the Sm-Nd studies.

AMINO ACID ANALYSES OF THE ANTARCTIC CM2 METEORITES ALH 83100 AND LEW 90500 USING LIQUID CHROMATOGRAPHY-TIME OF FLIGHT-MASS SPECTROMETRY

NASA Technical Reports Server (NTRS)

Glavin, D. P.; Dworkin, J. P.; Aubrey, A.; Botta, O.; Doty, J. H., III; Bada, J. L.

2001-01-01

The investigation of organic compounds in primitive carbonaceous meteorites provides a record of the chemical processes that occurred in the early solar system. In particular, amino acids have been shown to be potential indicators in tracing the nature of carbonaceous chondrite parent bodies [ 13. The delivery of amino acids by carbonaceous chondrites to the early Earth could have been any important source of the Earth's prebiotic organic inventory [2]. Over 80 different amino acids have been detected in the Murchison CM2 meteorite, most of them completely non-existent in the terrestrial biosphere [3]. We have optimized a new liquid chromatography-time-of-flight-mass spectrometry (LC-ToF-MS) technique coupled with OPAMAC derivatization in order to detect amino acids in meteorite extracts by UV fluorescence and exact mass simultaneously. The detection limit of the LC-ToF-MS instrument for amino acids is at least 3 orders of magnitude lower than traditional GC-MS techniques. Here we report on the first analyses of amino acids and their enantiomeric abundances in the CM2 carbonaceous meteorites ALH 83100, LEW 90500, and Murchison using this new LC-ToF-MS instrument configuration. Amino acid analyses of any kind for the CM meteorite ALH 83100 have not previously been reported.

Biosignatures in the Recrystallized Shock Melt Pocket of ALH-77005 Shergottite — Clues to Martian Life

NASA Astrophysics Data System (ADS)

Gyollai, I.; Polgári, M.; Bérczi, Sz.; Gucsik, A.; Pál-Molnár, E.

2017-11-01

In the spinifex textured, recrystallized shock melt portion in ALH 77005 shergottite mineralized microbially produced texture (MMPT) - in form of pearl necklace-like, vermiform inner signatures - was measured, which we propose to have Martian origin.

A Hypothesis for the Abiotic and Non-Martian Origins of Putative Signs of Ancient Martian Life in ALH84001

NASA Technical Reports Server (NTRS)

Treiman, Allan H.

2001-01-01

Putative evidence of martian life in ALH84001 can be explained by abiotic and non-martian processes consistent with the meteorite's geological history. Additional information is contained in the original extended abstract.

Carbon Compounds from Mars Found Inside Meteorite ALH84001

NASA Image and Video Library

1996-08-08

This 4.5 billion-year-old rock, labeled meteorite ALH84001, is one of 10 rocks from Mars in which researchers have found organic carbon compounds that originated on Mars without involvement of life. http://photojournal.jpl.nasa.gov/catalog/PIA00289

Rock Magnetic and Ferromagnetic Resonance Tests of Biogenic Magnetite in ALH84001

NASA Technical Reports Server (NTRS)

Kirschvink, J. L.; Kim, S.; Weiss, B. P.; Shannon, D. M.; Kobayashi, A. K.

2002-01-01

Three separate rock magnetic and ferromagnetic resonance tests support the hypothesis that between 25 and 50% of the fine-grained magnetite in the Martian meteorite ALH84001 was formed via biological processes. Additional information is contained in the original extended abstract.

Truncated Hexa-Octahedral Magnetites: Biosignatures in Terrestrial Samples and Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

Thomas-Keprta, Kathie L.; Clemett, Simon J.; Bazylinski, Dennis A.; Kirschvink, Joseph L.; McKay, David S.; Wentworth, Susan J.; Vali, H.; Gibson, Everett K.

2001-01-01

We suggest that the observation of truncated hexa-octahedral magnetites in ALH84001 are both consistent with, and in the absence of terrestrial inorganic analogs, likely formed by biogenic processes. Additional information is contained in the original extended abstract.

Risk profile of breast cancer following atypical hyperplasia detected through organized screening.

PubMed

Buckley, Elizabeth; Sullivan, Tom; Farshid, Gelareh; Hiller, Janet; Roder, David

2015-06-01

Few population-based data are available indicating the breast cancer risk following detection of atypia within a breast screening program. Prospectively collected data from the South Australian screening program were linked with the state cancer registry. Absolute and relative breast cancer risk estimates were calculated for ADH and ALH separately, and by age at diagnosis and time since diagnosis. Post-hoc analysis was undertaken of the effect of family history on breast cancer risk. Women with ADH and ALH had an increase in relative risk for malignancy (ADH HR 2.81 [95% CI 1.72, 4.59] and (ALH HR 4.14 [95% CI 1.97, 8.69], respectively. Differences in risk profile according to time since diagnosis and age at diagnosis were not statistically significant. Estimates of the relative risk of breast cancer are necessary to inform decisions regarding clinical management and/or treatment of women with ADH and ALH. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cryogenic Origin for Mars Analog Carbonates in the Bockfjord Volcanic Complex Svalbard (Norway)

NASA Technical Reports Server (NTRS)

Amundsen, H. E. F.; Benning, L.; Blake, D. F.; Fogel, M.; Ming, D.; Skidmore, M.; Steele, A.

2011-01-01

The Sverrefjell and Sigurdfjell eruptive centers in the Bockfjord Volcanic Complex (BVC) on Svalbard (Norway) formed by subglacial eruptions ca. 1 Ma ago. These eruptive centers carry ubiquitous magnesian carbonate deposits including dolomitemagnesite globules similar to those in the Martian meteorite ALH84001. Carbonates in mantle xenoliths are dominated by ALH84001 type carbonate globules that formed during quenching of CO2-rich mantle fluids. Lava hosted carbonates include ALH84001 type carbonate globules occurring throughout lava vesicles and microfractures and massive carbonate deposits associated with vertical volcanic vents. Massive carbonates include < or equal 5 cm thick magnesite deposits protruding downwards into clear blue ice within volcanic vents and carbonate cemented lava breccias associated with volcanic vents. Carbonate cements comprise layered deposits of calcite, dolomite, huntite, magnesite and aragonite associated with ALH84001 type carbonate globules lining lava vesicles. Combined Mossbauer, XRD and VNIR data show that breccia carbonate cements at Sverrefjell are analog to Comanche carbonates at Gusev crater.

Angiolymphoid hyperplasia with eosinophilia-acquired port-wine-stain-like lesions: attempt at treatment with the argon laser.

PubMed

Pasyk, K A; Elsenety, E N; Schelbert, E B

1988-01-01

An unusual case of angiolymphoid hyperplasia with eosinophilia (ALHE) simulating port-wine stain in a 50-year-old woman is reported. The lesions of ALHE are typically papules or subcutaneous masses that range from light pink to red-brown in color. In addition to the usual histologic findings of ALHE, the biopsy in our patient showed some fibrin-like material and fibrous long-spacing collagen on ultrastructural examination. This unusual lesion necessitates biopsy because the differential diagnosis includes port-wine stain, sarcoidosis, lupus erythematosus, and non-Hodgkin lymphoma (mycosis fungoides). Many different forms of treatment have been attempted for ALHE including radiotherapy, cytotoxic chemotherapy, corticosteroids, and antibiotics. The lesions in our patient responded to argon laser therapy and surgical excision, though there has been recurrence on the border of the treated area. Because laser energy is noncumulative in the tissues and effective in removing the lesions, we recommend it as the treatment of choice for these lesions.

SHEPARD, ALAN B., JR. ASTRONAUT - WASHINGTON, DC

NASA Image and Video Library

1963-05-06

S63-06268 (8 May 1963) --- Astronaut Alan B. Shepard, Jr., receives his NASA's Distinguished Service Medal from President John F. Kennedy, after his Mercury-Redstone 3 (MR-3) flight, in a Rose Garden ceremony on May 8, 1961 at the White House.

A first principles calculation and statistical mechanics modeling of defects in Al-H system

NASA Astrophysics Data System (ADS)

Ji, Min; Wang, Cai-Zhuang; Ho, Kai-Ming

2007-03-01

The behavior of defects and hydrogen in Al was investigated by first principles calculations and statistical mechanics modeling. The formation energy of different defects in Al+H system such as Al vacancy, H in institution and multiple H in Al vacancy were calculated by first principles method. Defect concentration in thermodynamical equilibrium was studied by total free energy calculation including configuration entropy and defect-defect interaction from low concentration limit to hydride limit. In our grand canonical ensemble model, hydrogen chemical potential under different environment plays an important role in determing the defect concentration and properties in Al-H system.

Histology after lumpectomy in women with epithelial atypia on stereotactic vacuum-assisted breast biopsy.

PubMed

Graesslin, O; Antoine, M; Chopier, J; Seror, J Y; Flahault, A; Callard, P; Daraï, E; Uzan, S

2010-02-01

Large-core needle biopsy of the breast (LCNB) and vacuum-assisted breast biopsy (VABB) are widely used as alternatives to open surgical biopsy (OSB) for initial diagnosis of mammographic abnormalities. Between 18% and 80% of cases in which such specimens show atypical lobular hyperplasia (ALH) or atypical ductal hyperplasia (ADH) are found to be malignant at surgery. From 1999 to 2005, 68 women with mammographic abnormalities were sampled by stereotactic VABB and presented atypical epithelial hyperplasia. Immunohistochemical staining with anti-cytokeratin 5/6 and anti-E-cadherin antibodies was performed. All women underwent a lumpectomy. Clinical, radiological or histological factors predictive of the risk of finding malignancy at surgery were sought. VABB initially showed 28 cases of ADH, 32 cases of ALH, one case of flat epithelial atypia, five cases of mixed atypia, and two cases of Lobular Carcinoma In Situ (LCIS). After slide review with immunohistochemical staining, two cases of ADH were reclassified as simple hyperplasia and two cases of ALH were reclassified as mixed atypia. Seven lesions (10.3%) that appeared to be benign on VABB were found to be malignant on OSB (Ductal Carcinoma In Situ (DCIS) in six cases and invasive ductal carcinoma in one case). ADH was the only predictive factor of malignancy on OSB (p=0.04 versus ALH). ADH diagnosed by vacuum-assisted breast biopsy frequently corresponds to cancer on open surgical biopsy. Surgical excision of all breast lesions containing atypical hyperplasia on percutaneous biopsy can be recommended. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Did an Impact Make the Mysterious Microscopic Magnetite Crystals in ALH 84001?

NASA Astrophysics Data System (ADS)

Taylor, G. J.

2007-10-01

Fervent debate swirls around microscopic crystals of magnetite (Fe3O4) in Martian meteorite ALH 84001. Some investigators suggest that the crystals are evidence of past life on Mars, citing magnetite crystals of similar chemical compositions and sizes made by magnetotactic bacteria on Earth. Others cite assorted experiments and observations to argue that the important little crystals formed entirely by non-biological processes, hence say nothing about life on Mars. One of those processes is the decomposition of iron carbonate (the mineral siderite), which occurs in ALH 84001. Researchers argue that heating this mineral causes it to decompose into magnetite and CO2 gas. Experiments showing this were done by heating siderite and observing that it decomposed and formed magnetite, but nobody had shock-heated siderite to see if magnetite crystals formed. (Shock is a rapid, strong rise and fall in pressure. It happens under many circumstances, including meteorite impacts.) The lack of shock experiments has been solved by Mary Sue Bell (University of Houston and Jacobs Engineering). She experimentally shocked samples of siderite at the Experimental Impact Laboratory at the Johnson Space Center. She shows that magnetite crystals of the right size and composition formed when samples were shocked to 49 GPa (about 500,000 times the pressure at the Earth's surface). This is more evidence for a non-biological origin for the magnetite crystals in ALH 84001 and is consistent with what we know about the impact history of the rock. There seems to be growing evidence against a biological origin, but don't expect these results to completely settle the debate!

Evidence for shock heating and constraints on Martian surface temperatures revealed by 40Ar/ 39Ar thermochronometry of Martian meteorites

NASA Astrophysics Data System (ADS)

Cassata, William S.; Shuster, David L.; Renne, Paul R.; Weiss, Benjamin P.

2010-12-01

The thermal histories of Martian meteorite are important for the interpretation of petrologic, geochemical, geochronological, and paleomagnetic constraints that they provide on the evolution of Mars. In this paper, we quantify 40Ar/ 39Ar ages and Ar diffusion kinetics of Martian meteorites Allan Hills (ALH) 84001, Nakhla, and Miller Range (MIL) 03346. We constrain the thermal history of each meteorite and discuss the resulting implications for their petrology, paleomagnetism, and geochronology. Maskelynite in ALH 84001 yields a 40Ar/ 39Ar isochron age of 4163 ± 35 Ma, which is indistinguishable from recent Pb-Pb ( Bouvier et al., 2009a) and Lu-Hf ages ( Lapen et al., 2010). The high precision of this result arises from clear resolution of a reproducible trapped 40Ar/ 36Ar component in maskelynite in ALH 84001 ( 40Ar/ 36Ar = 632 ± 90). The maskelynite 40Ar/ 39Ar age predates the Late Heavy Bombardment and likely represents the time at which the original natural remanent magnetization (NRM) component observed in ALH 84001 was acquired. Nakhla and MIL 03346 yield 40Ar/ 39Ar isochron ages of 1332 ± 24 and 1339 ± 8 Ma, respectively, which we interpret to date crystallization. Multi-phase, multi-domain diffusion models constrained by the observed Ar diffusion kinetics and 40Ar/ 39Ar age spectra suggest that localized regions within both ALH 84001 and Nakhla were intensely heated for brief durations during shock events at 1158 ± 110 and 913 ± 9 Ma, respectively. These ages may date the marginal melting of pyroxene in each rock, mobilization of carbonates and maskelynite in ALH 84001, and NRM overprints observed in ALH 84001. The inferred peak temperatures of the shock heating events (>1400 °C) are sufficient to mobilize Ar, Sr, and Pb in constituent minerals, which may explain some of the dispersion observed in 40Ar/ 39Ar, Rb-Sr, and U-Th-Pb data toward ages younger than ˜4.1 Ga. The data also place conservative upper bounds on the long-duration residence temperatures of the ALH 84001 and Nakhla protolith to be 22-∞+8 °C and 81-∞+9 °C over the last ˜4.16 Ga and ˜1.35 Ga, respectively. MIL 03346 has apparently not experienced significant shock-heating since it crystallized, consistent with the fact that various chronometers yield concordant ages.

Astronaut Alan Bean during news conference prior to Skylab 3 mission

NASA Image and Video Library

1973-06-29

S73-30113 (30 June 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, ponders a question from a newsman during the premission press conference on June 30, 1973, in the Building 1 large auditorium at Johnson Space Center. Photo credit: NASA

New Methods for Representing and Interacting with Qualitative Geographic Information

DTIC Science & Technology

2012-10-31

Penn State University Report on Component 3: SensePlace2 Evaluation Anthony C. Robinson, Scott Pezanowski, Alexander Savelyev , and Alan M...NUMBER 6. AUTHOR(S) Alexander Savelyev , Scott Pezanowski, Anthony C. Robinson, and Alan M. MacEachren 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...2012. SensePlace2 Interface Mini-Guide Alan M. MacEachren, Alexander Savelyev , and Scott Pezanowski GeoVISTA Center, Pennsylvania State University

Mineralization of Bacteria in Terrestrial Basaltic Rocks: Comparison With Possible Biogenic Features in Martian Meteorite Allan Hills 84001

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K. L.; McKay, D. S.; Wentworth, S. J.; Stevens, T. O.; Taunton, A. E.; Allen, C. C.; Gibson, E. K., Jr.; Romanek, C. S.

1998-01-01

The identification of biogenic features altered by diagenesis or mineralization is important in determining whether specific features in terrestrial rocks and in meteorites may have a biogenic origin. Unfortunately, few studies have addressed the formation of biogenic features in igneous rocks, which may be important to these phenomena, including the controversy over possible biogenic features in basaltic martian meteorite ALH84001. To explore the presence of biogenic features in igneous rocks, we examined microcosms growing in basaltic small-scale experimental growth chambers or microcosms. Microbial communities were harvested from aquifers of the Columbia River Basalt (CRB) group and grown in a microcosm containing unweathered basalt chips and groundwater (technique described in. These microcosms simulated natural growth conditions in the deep subsurface of the CRB, which should be a good terrestrial analog for any putative martian subsurface ecosystem that may have once included ALH84001. Here we present new size measurements and photomicrographs comparing the putative martian fossils to biogenic material in the CRB microcosms. The range of size and shapes of the biogenic features on the CRB microcosm chips overlaps with and is similar to those on ALH84001 chips. Although this present work does not provide evidence for the biogenicity of ALH84001 features, we believe that, based on criteria of size, shape, and general morphology, a biogenic interpretation for the ALH84001 features remains plausible.

Building "Applied Linguistic Historiography": Rationale, Scope, and Methods

ERIC Educational Resources Information Center

Smith, Richard

2016-01-01

In this article I argue for the establishment of "Applied Linguistic Historiography" (ALH), that is, a new domain of enquiry within applied linguistics involving a rigorous, scholarly, and self-reflexive approach to historical research. Considering issues of rationale, scope, and methods in turn, I provide reasons why ALH is needed and…

Truncated hexa-octahedral magnetite crystals in ALH84001: Presumptive biosignatures

PubMed Central

Thomas-Keprta, Kathie L.; Clemett, Simon J.; Bazylinski, Dennis A.; Kirschvink, Joseph L.; McKay, David S.; Wentworth, Susan J.; Vali, Hojatollah; Gibson, Everett K.; McKay, Mary Fae; Romanek, Christopher S.

2001-01-01

McKay et al. [(1996) Science 273, 924–930] suggested that carbonate globules in the meteorite ALH84001 contained the fossil remains of Martian microbes. We have characterized a subpopulation of magnetite (Fe3O4) crystals present in abundance within the Fe-rich rims of these carbonate globules. We find these Martian magnetites to be both chemically and physically identical to terrestrial, biogenically precipitated, intracellular magnetites produced by magnetotactic bacteria strain MV-1. Specifically, both magnetite populations are single-domain and chemically pure, and exhibit a unique crystal habit we describe as truncated hexa-octahedral. There are no known reports of inorganic processes to explain the observation of truncated hexa-octahedral magnetites in a terrestrial sample. In bacteria strain MV-1 their presence is therefore likely a product of Natural Selection. Unless there is an unknown and unexplained inorganic process on Mars that is conspicuously absent on the Earth and forms truncated hexa-octahedral magnetites, we suggest that these magnetite crystals in the Martian meteorite ALH84001 were likely produced by a biogenic process. As such, these crystals are interpreted as Martian magnetofossils and constitute evidence of the oldest life yet found. PMID:11226210

Truncated hexa-octahedral magnetite crystals in ALH84001: presumptive biosignatures

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K. L.; Clemett, S. J.; Bazylinski, D. A.; Kirschvink, J. L.; McKay, D. S.; Wentworth, S. J.; Vali, H.; Gibson, E. K. Jr; McKay, M. F.; Romanek, C. S.

2001-01-01

McKay et al. [(1996) Science 273, 924-930] suggested that carbonate globules in the meteorite ALH84001 contained the fossil remains of Martian microbes. We have characterized a subpopulation of magnetite (Fe(3)O(4)) crystals present in abundance within the Fe-rich rims of these carbonate globules. We find these Martian magnetites to be both chemically and physically identical to terrestrial, biogenically precipitated, intracellular magnetites produced by magnetotactic bacteria strain MV-1. Specifically, both magnetite populations are single-domain and chemically pure, and exhibit a unique crystal habit we describe as truncated hexa-octahedral. There are no known reports of inorganic processes to explain the observation of truncated hexa-octahedral magnetites in a terrestrial sample. In bacteria strain MV-1 their presence is therefore likely a product of Natural Selection. Unless there is an unknown and unexplained inorganic process on Mars that is conspicuously absent on the Earth and forms truncated hexa-octahedral magnetites, we suggest that these magnetite crystals in the Martian meteorite ALH84001 were likely produced by a biogenic process. As such, these crystals are interpreted as Martian magnetofossils and constitute evidence of the oldest life yet found.

The Carbonates in ALH 84001 Record the Evolution of the Martian Atmosphere Through Multiple Formation Events

NASA Technical Reports Server (NTRS)

Shaheen, R.; Niles, P. B.; Corrgan, C.

2012-01-01

Current Martian conditions restrict the presence of liquid water due to low temperatures (approx 210K), a thin atmosphere (approx 7mb), and intense UV radiation. However, past conditions on Mars may have been different with the possibility that the ancient Martian climate was warm and wet with a dense CO2 atmosphere. The cycling of carbon on Mars through atmospheric CO2 and carbonate minerals is critical for deciphering its climate history. In particular stable isotopes contained in carbonates can provide information of their origin and formation environment as well as possibly hinting at the composition of global reservoirs such as atmospheric CO2. Martian meteorite ALH 84001 contains widely studied carbonate rosettes that have been dated to approx. 3.9 Ga and have been used to interpret climatic conditions present at that time. However, there is mount-ing evidence for multiple episodes of carbonate formation in ALH 84001 with potentially distinct isotopic compositions. This study seeks to tease out these different carbonate assemblages using stepped phosphoric acid dissolution and analysis of carbon and triple oxygen stable isotopes. In addition, we report SIMS analyses of the delta O-18 several petrographically unusual carbonate phases in the meteorite.

The History of Allan Hills 84001 Revised: Multiple Shock Events

NASA Technical Reports Server (NTRS)

Treiman, Allan H.

1998-01-01

The geologic history of Martian meteorite Allan Hills (ALH) 84001 is more complex than previously recognized, with evidence for four or five crater-forming impacts onto Mars. This history of repeated deformation and shock metamorphism appears to weaken some arguments that have been offered for and against the hypothesis of ancient Martian life in ALH 84001. Allan Hills 84001 formed originally from basaltic magma. Its first impact event (I1) is inferred from the deformation (D1) that produced the granular-textured bands ("crush zones") that transect the original igneous fabric. Deformation D1 is characterized by intense shear and may represent excavation or rebound flow of rock beneath a large impact crater. An intense thermal metamorphism followed D1 and may be related to it. The next impact (I2) produced fractures, (Fr2) in which carbonate "pancakes" were deposited and produced feldspathic glass from some of the igneous feldspars and silica. After I2, carbonate pancakes and globules were deposited in Fr2 fractures and replaced feldspathic glass and possibly crystalline silicates. Next, feldspars, feldspathic glass, and possibly some carbonates were mobilized and melted in the third impact (I3). Microfaulting, intense fracturing, and shear are also associated with 13. In the fourth impact (I4), the rock was fractured and deformed without significant heating, which permitted remnant magnetization directions to vary across fracture surfaces. Finally, ALH 84001 was ejected from Mars in event I5, which could be identical to I4. This history of multiple impacts is consistent with the photogeology of the Martian highlands and may help resolve some apparent contradictions among recent results on ALH 84001. For example, the submicron rounded magnetite grains in the carbonate globules could be contemporaneous with carbonate deposition, whereas the elongate magnetite grains, epitaxial on carbonates, could be ascribed to vapor-phase deposition during I3.

Astronaut Alan B. Shepard has his blood pressure and temperature checked

NASA Image and Video Library

1961-01-01

S61-02740 (5 May 1961) --- Astronaut Alan B. Shepard Jr. has his heart rate checked prior to his Mercury-Redstone 3 (MR-3) mission, the first American manned suborbital spaceflight. The attending physician is Dr. William K. Douglas. Photo credit: NASA or National Aeronautics and Space Administration

Astronaut Alan B. Shepard has his blood pressure and temperature checked

NASA Technical Reports Server (NTRS)

1961-01-01

Astronaut Alan B. Shepard has a thermometer in his mouth to check his temperature checked prior to his Mercury-Redstone 3 (MR-3) mission, the first American manned suborbital space flight (02739); Shepard has his heart rate checked. The attending physician is Dr. William K. Douglas (02740).

Statistical Analyses Comparing Prismatic Magnetite Crystals in ALH84001 Carbonate Globules with those from the Terrestrial Magnetotactic Bacteria Strain MV-1

NASA Technical Reports Server (NTRS)

Thomas-Keprta, Kathie L.; Clemett, Simon J.; Bazylinski, Dennis A.; Kirschvink, Joseph L.; McKay, David S.; Wentworth, Susan J.; Vali, H.; Gibson, Everett K.

2000-01-01

Here we use rigorous mathematical modeling to compare ALH84001 prismatic magnetites with those produced by terrestrial magnetotactic bacteria, MV-1. We find that this subset of the Martian magnetites appears to be statistically indistinguishable from those of MV-1.

Detection and variability of Aster Yellows Phytoplasma Titer in its insect vector, Macrosteles quadrilineatus (Hemiptera: Cicadellidae)

USDA-ARS?s Scientific Manuscript database

The aster yellows phytoplasma (AYp) is transmitted by the aster leafhopper (ALH), Macrosteles quadrilineatus Forbes, in a persistent and propagative manner. To study AYp replication and examine the variability of AYp titer in individual ALHs, we developed a quantitative, real-time PCR (qPCR) assay t...

Coordinated In Situ Nanosims Analyses of H-C-O Isotopes in ALH 84001 Carbonates

NASA Technical Reports Server (NTRS)

Usui, T.; Alexander, C. M. O'D.; Wang, J.; Simon, J. I.; Jones, J. H.

2016-01-01

The surface geology and geomorphology of Mars indicate that it was once warm enough to maintain a large body of liquid water on its surface, though such a warm environment might have been transient. This study reports the hydrogen, carbon, and oxygen isotope compositions of the ancient atmosphere/hydrosphere of Mars based on in situ ion microprobe analyses of approximately 4 Ga-old carbonates in Allan Hills (ALH) 84001. The ALH 84001 carbonates are the most promising targets because they are thought to have formed from fluid that was closely associated with the Noachian atmosphere. While there are a number of carbon and oxygen isotope studies of the ALH 84001 carbonates, in situ hydrogen isotope analyses of these carbonates are limited and were reported more than a decade ago. Well-documented coordinated in situ analyses of carbon, oxygen and hydrogen isotopes provide an internally consistent dataset that can be used to constrain the nature of the Noachian atmosphere/hydrosphere and may eventually shed light on the hypothesis of ancient watery Mars.

A Thermal Infrared Emission Spectra Library for Unpowdered Meteorites

NASA Astrophysics Data System (ADS)

Ashley, J. W.; Christensen, P. R.

2007-12-01

Mid-infrared thermal emission spectra have been obtained for whole-rock (unpowdered) samples of the following 25 meteorites: Abee, Admire, Allende, Bondoc, Brahin, Bruderheim, Canyon Diablo, Carichic, Clover Springs, Dhofar 007, Estherville, Holbrook, Juancheng, Kapoeta, Long Island, Marion, Modoc, ALH77225, ALH77233, ALH84082, LEW85322, ALH85025, ALH79029, ALH77004, and LEW86015. Meteorites were provided through the Center for Meteorite Studies at ASU, Johnson Space Center and the NASA Antarctic Meteorite Working Group, and from private collections. The database was prepared to aid in the on-going detection and interpretation of meteorites on Mars using the Miniature Thermal Emission Spectrometer (Mini-TES) instruments on both Mars Exploration Rovers. It therefore includes several specimens of low, moderate, and high weathering intensities, reflecting different levels of water exposure in desert and non-desert environments. Unweathered falls are also considered. Samples represent all three chondrite classes, stony irons (mesosiderites and pallasites), and select achondrites. Special consideration is given to dust-covered iron-nickel meteorites as part of a separate study designed to evaluate the Mini-TES spectra of iron-nickel meteorites on Mars. All samples were analyzed at or near a temperature of 80° C using a modified Nicolet Nexus 670 FT-IR spectrometer at the Mars Space Flight Facility at Arizona State University. Data were collected within the 2000 to 200 wavenumber (5 to 50 microns) mid-infrared range. The results show that many meteorite types display moderate to wide variability in the depth and position of prominent absorption features, making them easily distinguishable from each other. Most previous meteorite spectroscopy studies have either focused on near-infrared reflectance spectra [e.g. 1], and/or involved powdered samples to represent asteroid regoliths in the mid-infrared [e.g. 2 & 3]. Particle size- related issues are often at the heart of interpretation of asteroid spectroscopic studies in the mid-infrared [4]. However, the high-resolution Itokawa imaging results of the Hayabusa mission have shown that not all asteroid surfaces are dominated by powdered materials [e.g. 5]. It is therefore anticipated that whole-rock, mid-infrared emission spectra may serve a further purpose in studies conducted with Spitzer Space Telescope and other space-born observatories equipped with mid-infrared detectors. The library will therefore continue to be augmented with additional spectra, to include unweathered carbonaceous chondrites and achondrites at a minimum. All spectra are available through the Arizona State University Thermal Emission Spectral Library. References: [1] Sato K. and Miyamoto M. (1998) Antarctic Meteorite Research 11, 155-162. [2] Salisbury J.W. et al. (1991) NASA Technical Memorandum #4300, 262-204. [3] Dameron S.N. and Burbine T.H. (2006) LPSC XXXVII, abstract #1828. [4] Emery J.P. et al. (2006) Icarus 182, 496-512. [5] Miyamoto et al. (2007) Science 316, 1011- 1014.

Formation of "Chemically Pure" Magnetite from Mg-Fe-Carbonates Implications for the Exclusively Inorganic Origin of Magnetite and Sulfides in Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

Golden, D. C.; Ming, Douglas W.; Lauer, H. V., Jr.; Morris, R. V.; Trieman, A. H.; McKay, G. A.

2006-01-01

Magnetite and sulfides in the black rims of carbonate globules in Martian meteorite ALH84001 have been studied extensively because of the claim by McKay et al. that they are biogenic in origin. However, exclusively inorganic (abiotic) processes are able to account for the occurrence of carbonate-sulfide-magnetite assemblages in the meteorite. We have previously precipitated chemically zoned and sulfide-bearing carbonate globules analogous to those in ALH84001 (at less than or equal to 150 C) from multiple fluxes of variable-composition Ca-Mg-Fe-CO2-S-H2O solutions. Brief heating of precipitated globules to approx. 470 C produced magnetite and pyrrhotite within the globules by thermal decomposition of siderite and pyrite, respectively. We have also shown that morphology of magnetite formed by inorganic thermal decomposition of Fe-rich carbonate is similar to the morphology of so-called biogenic magnetite in the carbonate globules of ALH84001. Magnetite crystals in the rims of carbonate globules in ALH84001 are chemically pure [Note: "Chemically pure" is defined here as magnetite with Mg at levels comparable or lower than Mg detected by [8] in ALH84001 magnetite]. A debate continues on whether or not chemically pure magnetite can form by the thermal decomposition of mixed Mg-Fe-carbonates that have formed under abiotic conditions. Thomas-Keprta et al. argue that it is not possible to form Mg-free magnetite from Mg-Fe-carbonate based on thermodynamic data. We previously suggested that chemically pure magnetite could form by the thermal decomposition of relatively pure siderite in the outer rims of the globules. Mg-Fe-carbonates may also thermally decompose under conditions conducive for formation of chemically pure magnetite. In this paper we show through laboratory experiments that chemically pure magnetite can form by an inorganic process from mixed Mg-Fe-carbonates.

Submicron magnetite grains and carbon compounds in Martian meteorite ALH84001: inorganic, abiotic formation by shock and thermal metamorphism.

PubMed

Treiman, Allan H

2003-01-01

Purported biogenic features of the ALH84001 Martian meteorite (the carbonate globules, their submicron magnetite grains, and organic matter) have reasonable inorganic origins, and a comprehensive hypothesis is offered here. The carbonate globules were deposited from hydrothermal water, without biological mediation. Thereafter, ALH84001 was affected by an impact shock event, which raised its temperature nearly instantaneously to 500-700K, and induced iron-rich carbonate in the globules to decompose to magnetite and other minerals. The rapidity of the temperature increase caused magnetite grains to nucleate in abundance; hence individual crystals were very small. Nucleation and growth of magnetite crystals were fastest along edges and faces of the precursor carbonate grains, forcing the magnetite grains to be platy or elongated, including the "truncated hexa-octahedra" shape. ALH84001 had formed at some depth within Mars where the lithostatic pressure was significantly above that of Mars' surface. Also, because the rock was at depth, the impact heat dissipated slowly. During this interval, magnetite crystals approached chemical equilibria with surrounding minerals and gas. Their composition, nearly pure Fe(3)O(4), reflects those of equilibria; elements that substitute into magnetite are either absent from iron-rich carbonate (e.g., Ti, Al, Cr), or partitioned into other minerals during magnetite formation (Mg, Mn). Many microstructural imperfections in the magnetite grains would have annealed out as the rock cooled. In this post-shock thermal regime, carbon-bearing gas from the decomposition of iron carbonates reacted with water in the rock (or from its surroundings) to produce organic matter via Fischer-Tropschlike reactions. Formation of such organic compounds like polycyclic aromatic hydrocarbons would have been catalyzed by the magnetite (formation of graphite, the thermochemically stable phase, would be kinetically hindered).

Ab initio studies on Al(+)(H(2)O)(n), HAlOH(+)(H(2)O)(n-1), and the size-dependent H(2) elimination reaction.

PubMed

Siu, Chi-Kit; Liu, Zhi-Feng; Tse, John S

2002-09-11

We report computational studies on Al(+)(H(2)O)(n), and HAlOH(+)(H(2)O)(n-1), n = 6-14, by the density functional theory based ab initio molecular dynamics method, employing a planewave basis set with pseudopotentials, and also by conventional methods with Gaussian basis sets. The mechanism for the intracluster H(2) elimination reaction is explored. First, a new size-dependent insertion reaction for the transformation of Al(+)(H(2)O)(n), into HAlOH(+)(H(2)O)(n-1) is discovered for n > or = 8. This is because of the presence of a fairly stable six-water-ring structure in Al(+)(H(2)O)(n) with 12 members, including the Al(+). This structure promotes acidic dissociation and, for n > or = 8, leads to the insertion reaction. Gaussian based BPW91 and MP2 calculations with 6-31G* and 6-31G** basis sets confirmed the existence of such structures and located the transition structures for the insertion reaction. The calculated transition barrier is 10.0 kcal/mol for n = 9 and 7.1 kcal/mol for n = 8 at the MP2/6-31G** level, with zero-point energy corrections. Second, the experimentally observed size-dependent H(2) elimination reaction is related to the conformation of HAlOH(+)(H(2)O)(n-1), instead of Al(+)(H(2)O)(n). As n increases from 6 to 14, the structure of the HAlOH(+)(H(2)O)(n-1) cluster changes into a caged structure, with the Al-H bond buried inside, and protons produced in acidic dissociation could then travel through the H(2)O network to the vicinity of the Al-H bond and react with the hydride H to produce H(2). The structural transformation is completed at n = 13, coincident approximately with the onset of the H(2) elimination reaction. From constrained ab initio MD simulations, we estimated the free energy barrier for the H(2) elimination reaction to be 0.7 eV (16 kcal/mol) at n = 13, 1.5 eV (35 kcal/mol) at n = 12, and 4.5 eV (100 kcal/mol) at n = 8. The existence of transition structures for the H(2) elimination has also been verified by ab initio calculations at the MP2/6-31G** level. Finally, the switch-off of the H(2) elimination for n > 24 is explored and attributed to the diffusion of protons through enlarged hydrogen bonded H(2)O networks, which reduces the probability of finding a proton near the Al-H bond.

Astronaut Alan B. Shepard has his blood pressure and temperature checked

NASA Image and Video Library

1961-01-01

S61-02749 (5 May 1961) --- Astronaut Alan B. Shepard Jr. has his blood pressure and temperature checked prior to his Mercury-Redstone 3 (MR-3) mission, the first American manned spaceflight. The attending physician is Dr. William K. Douglas. Photo credit: NASA or National Aeronautics and Space Administration

Disruptive effects of light pollution on sleep in free-living birds: Season and/or light intensity-dependent?

PubMed

Raap, Thomas; Sun, Jiachen; Pinxten, Rianne; Eens, Marcel

2017-11-01

Light pollution or artificial light at night (ALAN) is an increasing anthropogenic environmental pollutant posing an important potential threat for wildlife. Evidence of its effects on animal physiology and behaviour is accumulating. However, in order to effectively mitigate light pollution it is important to determine which factors contribute to the severity of effects of ALAN. In this experimental study we explored whether there are seasonal-dependent effects of ALAN on sleep in free-living great tits (Parus major), an important model species. Additionally, we looked at whether light intensity determined the severity of effects of ALAN on sleep. We therefore exposed animals to artificial light inside the nest box (3lx) in December (winter) and February (pre-breeding season). Results from February were compared with the results from a previous study in February, using a lower light intensity (1.6lx). We found little evidence for a season-dependent response. Effects of ALAN hardly differed between high and low light intensity. ALAN disrupted sleep with as main effect a decrease in sleep duration (≈-40min) as animals woke up earlier (≈-24min). However, compared to a natural dark situation sleep onset was delayed by high but not by low light intensity of ALAN. Our study underlines earlier found disruptive effects of ALAN on sleep of free-living animals. While we found no conclusive evidence for seasonal or light intensity-dependent effects of ALAN, additional experimental work using lower light intensities might show such differences. Examining potential management options is crucial in mitigating disruptive effects of light pollution, which will be an important focus for future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Low-Cost alpha Alane for Hydrogen Storage

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

Fabian, Tibor; Petrie, Mark; Crouch-Baker, Steven

This project was directed towards the further development of the Savannah River National Laboratory (SRNL) lab-scale electrochemical synthesis of the hydrogen storage material alpha-alane and Ardica Technologies-SRI International (SRI) chemical downstream processes that are necessary to meet DoE cost metrics and transition alpha-alane synthesis to an industrial scale. Ardica has demonstrated the use of alpha-alane in a fuel-cell system for the U.S. Army WFC20 20W soldier power system that has successfully passed initial field trials with individual soldiers. While alpha-alane has been clearly identified as a desirable hydrogen storage material, cost-effective means for its production and regeneration on a scalemore » of use applicable to the industry have yet to be established. We focused on three, principal development areas: 1. The construction of a comprehensive engineering techno-economic model to establish the production costs of alpha-alane by both electrochemical and chemical routes at scale. 2. The identification of critical, cost-saving design elements of the electrochemical cell and the quantification of the product yields of the primary electrochemical process. A moving particle-bed reactor design was constructed and operated. 3. The experimental quantification of the product yields of candidate downstream chemical processes necessary to produce alpha-alane to complete the most cost-effective overall manufacturing process. Our techno-economic model shows that under key assumptions most 2015 and 2020 DOE hydrogen storage system cost targets for low and medium power can be achieved using the electrochemical alane synthesis process. To meet the most aggressive 2020 storage system cost target, $1/g, our model indicates that 420 metric tons per year (MT/y) production of alpha-alane is required. Laboratory-scale experimental work demonstrated that the yields of two of the three critical component steps within the overall “electrochemical process” were sufficiently high to meet this production target. In the case of the yield of the third step, the crystallization of alpha-alane from the primary alane-related product of the electrochemical reaction, further development is required.« less

Mechanism of sodium and chloride transport in the thin ascending limb of Henle.

PubMed Central

Imai, M; Kokko, J P

1976-01-01

Our previous in vitro studies have disclosed that the thin ascending limb of Henle (tALH) possesses some unique membrane characteristics. In those studies we failed to demonstrated active transport of sodium chloride by the tALH, although it was shown that the isotopic permeability to sodium and chloride was unusually high. However, we did not examine the mechanisms by which the apparent high permeation of sodium chloride occurs. Thus the purpose of the present studies was to elucidate the mechanism of sodium chloride transport across the isolated tALH of the rabbit by conducting four different types of studies: (1) comparison of the observed chloride and sodium flux ratios to those predicted by Ussing's equation under imposed salt concentration gradients; (2) kinetic evaluation of chloride and sodium fluxes; (3) examination of the effect of bromide on the kinetics of chloride transport; and (4) experiments to test for the existence of exchange diffusion of chloride. In the first set of studies the predicted and the theoretical flux ratios of sodium were identical in those experiments in which sodium chloride was added either to the perfusate or to the bath. However, the observed chloride flux ratio, lumen-to-bath/bath-to-lumen, was significantly lower than that predicted from Ussing's equation when 100 mM sodium chloride was added to the bath. In the second set of experiments the apparent isotopic permeability for sodium and for chloride was measured under varying perfusate and bath NaCl concentrations. There was no statistical change in the apparent sodium permeability coefficient when the NaCl concentration was raised by varying increments from 85.5 to 309.5 mM. However, permeation of 36Cl decrease significantly with an increase in Cl from 73.6 to 598.6 mM. These events could be explained by a two component chloride transport process consisting of simple diffusion and a saturable facilitated diffusion process with a Vmax = 3.71 neq mm-1 min-1. In the third set of studies it was shown that bromide inhibits transport of chloride and that the magnitude of inhibition is dependent on chloride concentrations. The fourth set of studies ruled out the existence of exchange diffusion. In conclusion, these studies indicate that sodium transport across tALH is by simple passive diffusion, while chloride transport across tALH involves at least two mechanisms: (1) simple passive diffusion; and (2) a specific membrane interaction process (carrier-mediated) which is competitively inhibited by bromide. PMID:993330

Astronaut Owen Garriott trims hair of Astronaut Alan Bean

NASA Technical Reports Server (NTRS)

1973-01-01

Scientist-Astronaut Owen K. Garriott, Skylab 3 science pilot, trims the hair of Astronaut Alan L. Bean, commander, in this on-board photograph from the Skylab Orbital Workshop (OWS). Bean holds a vacuum hose to gather in loose hair.

Astronaut Alan Bean doing acrobatics in OWS dome area

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, doing acrobatics in the dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. The dome area is about 22 feet in diameter and 19 feet from top to bottom.

Magnetite Formation from Thermal Decomposition of Siderite: Implications for Inorganic Magnetite Formation in Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

Morris, RIchard V.

2002-01-01

A biogenic mechanism for formation of a subpopulation magnetite in Martian meteorite ALH84001 has been suggested [McKay et al., 1996; Thomas-Keprta, et al., 2000]. We are developing experimental evidence for an alternating working hypothesis, that the subpopulation was produced inorganically by the thermal decomposition of siderite [Golden et al., 2000].

Materials Data on Na3AlH6 (SG:14) by Materials Project

DOE Data Explorer

Kristin Persson

2014-11-02

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

FOSB immunoreactivity in endothelia of epithelioid hemangioma (angiolymphoid hyperplasia with eosinophilia).

PubMed

Ortins-Pina, Ana; Llamas-Velasco, Mar; Turpin, Sara; Soares-de-Almeida, Luís; Filipe, Paulo; Kutzner, Heinz

2018-06-01

Accurate distinction of epithelioid hemangioma (EH) from its malignant mimics is paramount but remains challenging due to its wide morphological spectrum and lack of objective molecular markers. FOSB oncogenic activation was recently identified as a key event in endothelial proliferation. We sought to investigate the FOSB staining pattern in EH with angiolymphoid hyperplasia with eosinophilia (EH-AHLE) morphology and to evaluate its value in differential diagnosis of epithelioid vascular tumors. From the authors' files, 15 representative cases of EH-ALHE were selected and evaluated for their FOSB immunostaining pattern. Other vascular proliferations which can be morphological mimics were also tested: epithelioid hemangioendothelioma (EHE) (5 cases) and epithelioid angiosarcoma (EAS) (5 cases). All 15 cases of EH-ALHE showed strong and homogeneous FOSB nuclear expression in endothelial cells with ample cytoplasm and intracytoplasmic vacuoles. All cases of EHE and EAS lacked FOSB immunoreactivity or showed only incidental weak FOSB immunoreactivity in less than 5 nuclei per lesion. FOSB immunohistochemistry is sensitive in the diagnosis of EH-ALHE, and allows differentiation from its histological mimics. An immunohistochemical panel including not only pan-cytokeratin AE1/AE3 and endothelial markers, but also FOSB, helps in the diagnosis of epithelioid vascular tumors. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Astronaut Alan Bean looks over data acquisition camera on Skylab trainer

NASA Technical Reports Server (NTRS)

1972-01-01

Astronaut Alan L. Bean, commander for Skylab 3, the second manned Skylab mission, looks over the data acquisition camera mounted on the water tank in the upper level of the Orbital Workshop (OWS) one-G trainer at the Manned Spacecraft Center (MSC).

Hydrogen release reactions of Al-based complex hydrides enhanced by vibrational dynamics and valences of metal cations

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

Sato, T.; Ramirez-Cuesta, Anibal J.; Daemen, Luke L.

2016-08-31

Hydrogen release from Al-based complex hydrides composed of metal cation(s) and [AlH4] – was investigated using inelastic neutron scattering viewed from vibrational dynamics. Here, the hydrogen release followed the softening of translational and [AlH4] – librational modes, which was enhanced by vibrational dynamics and the valence(s) of the metal cation(s).

Successful Capture, Extraction and Identification of Hypervelocity CM2 Meteorite Fragments Shot by Light-Gas Gun

NASA Technical Reports Server (NTRS)

Snead, C.; Westphal, A. J.; Dominguez, G.; Zolensky, M. E.

2003-01-01

Here we report the successful capture, extraction and identification of two fragments of a CM2 meteorite (ALH83100) into lowdensity aerogel. The shot was carried out at the AVGR at NASAARC. A mixture of powdered ALH83100 and borosilicate glass microspheres was shot at 4.55.0 km/sec into 50 mg cm silicate aerogel.

High-Throughput Serum 25-Hydroxy Vitamin D Testing with Automated Sample Preparation.

PubMed

Stone, Judy

2016-01-01

Serum from bar-coded tubes, and then internal standard, are pipetted to 96-well plates with an 8-channel automated liquid handler (ALH). The first precipitation reagent (methanol:ZnSO4) is added and mixed with the 8-channel ALH. A second protein precipitating agent, 1 % formic acid in acetonitrile, is added and mixed with a 96-channel ALH. After a 4-min delay for larger precipitates to settle to the bottom of the plate, the upper 36 % of the precipitate/supernatant mix is transferred with the 96-channel ALH to a Sigma Hybrid SPE(®) plate and vacuumed through for removal of phospholipids and precipitated proteins. The filtrate is collected in a second 96-well plate (collection plate) which is foil-sealed, placed in the autosampler (ALS), and injected into a multiplexed LC-MS/MS system running AB Sciex Cliquid(®) and MPX(®) software. Two Shimadzu LC stacks, with multiplex timing controlled by MPX(®) software, inject alternately to one AB Sciex API-5000 MS/MS using positive atmospheric pressure chemical ionization (APCI) and a 1.87 min water/acetonitrile LC gradient with a 2.1 × 20 mm, 2.7 μm, C18 fused core particle column (Sigma Ascentis Express). LC-MS/MS through put is ~44 samples/h/LC-MS/MS system with dual-LC channel multiplexing. Plate maps are transferred electronically from the ALH and reformatted into LC-MS/MS sample table format using the Data Innovations LLC (DI) Instrument Manager middleware application. Before collection plates are loaded into the ALS, the plate bar code is manually scanned to download the sample table from the DI middleware to the LC-MS/MS. After acquisition-LC-MS/MS data is analyzed with AB Sciex Multiquant(®) software using customized queries, and then results are transferred electronically via a DI interface to the LIS. 2500 samples/day can be extracted by two analysts using four ALHs in 4-6 h. LC-MS/MS analysis of those samples on three dual-channel LC multiplexed LC-MS/MS systems requires 19-21 h and data analysis can be done by two analysts in 4-6 h.

Coastal urban lighting has ecological consequences for multiple trophic levels under the sea.

PubMed

Bolton, D; Mayer-Pinto, M; Clark, G F; Dafforn, K A; Brassil, W A; Becker, A; Johnston, E L

2017-01-15

Urban land and seascapes are increasingly exposed to artificial lighting at night (ALAN), which is a significant source of light pollution. A broad range of ecological effects are associated with ALAN, but the changes to ecological processes remain largely unstudied. Predation is a key ecological process that structures assemblages and responds to natural cycles of light and dark. We investigated the effect of ALAN on fish predatory behaviour, and sessile invertebrate prey assemblages. Over 21days fish and sessile assemblages were exposed to 3 light treatments (Day, Night and ALAN). An array of LED spotlights was installed under a wharf to create the ALAN treatments. We used GoPro cameras to film during the day and ALAN treatments, and a Dual frequency IDentification SONar (DIDSON) to film during the night treatments. Fish were most abundant during unlit nights, but were also relatively sedentary. Predatory behaviour was greatest during the day and under ALAN than at night, suggesting that fish are using structures for non-feeding purposes (e.g. shelter) at night, but artificial light dramatically increases their predatory behaviour. Altered predator behaviour corresponded with structural changes to sessile prey assemblages among the experimental lighting treatments. We demonstrate the direct effects of artificial lighting on fish behaviour and the concomitant indirect effects on sessile assemblage structure. Current and future projected use of artificial lights has the potential to significantly affect predator-prey interactions in marine systems by altering habitat use for both predators and prey. However, developments in lighting technology are a promising avenue for mitigation. This is among the first empirical evidence from the marine system on how ALAN can directly alter predation, a fundamental ecosystem process, and have indirect trophic consequences. Copyright © 2016 Elsevier B.V. All rights reserved.

[Construction and Characterization of B850-Only LH2 Energy Transfer System in Purple Bacteria].

PubMed

Li, Kai; Zhao, Chun-gui; Yue, Hui-ying; Yang, Su-ping; Qu, Yin-bo; Jiao, Nian-zhi

2015-04-01

To seek microscopic molecular mechanism of energy transfer and complex reconstitution in the photosynthesis, the conditions for construction of B850-only peripheral light-harvesting complex (LH2) and their properties were investigated using absorption, fluorescence spectroscopy, molecular sieve chromatography, ultrafiltration and sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) from the purple bacteria. The results indicated that bacteriochlorophylls (BChl) of B800 incubated in 10 mmo · L(-1) Tris-HCl (pH 8.0) buffer are selectively released from their binding sites of LH2 of Rhodobacter azotoformans (A-LH2) by 0.08% (W/V) SDS. B850-only A-LH2 was constructed after removing free BChl mixing with 10% methyl alcohol by ultrafiltration. B850 BChl was released after A-LH2 was incubated for 240 min in dark at room temperature (RT). While BChl of B800 incubated in pH 1.9 buffer were selectively released from their binding sites of LH2 of Rhodopseudomonas palustris (P-LH2). The authors acquired two components using molecular sieve chromatography. Free BChl of one component was not removed and self-assembled to P-LH2. The other removed free BChl and B850-only P-LH2 was constructed. B850 unchanged after P-LH2 was incubated. P-LH2 α and β subunits have different molecular weights, but those of A-LH2 are in the contrary. It is concluded that B850-only P-LH2 is more stable than A-LH2. The enigmatic split of the B800 absorption band was not observed in these LH2, but we acquired two kinds of B800-released LH2 from Rhodopseudomonas palustris. The authors' results may provide a new light to separate homogeneous Apoprotein LH2.

Physiological differences between female limited, alternative life history strategies: The Alba phenotype in the butterfly Colias croceus.

PubMed

Woronik, Alyssa; Stefanescu, Constanti; Käkelä, Reijo; Wheat, Christopher W; Lehmann, Philipp

Across a wide range of taxa, individuals within populations exhibit alternative life history strategies (ALHS) where their phenotypes dramatically differ due to divergent investments in growth, reproduction and survivorship, with the resulting trade-offs directly impacting Darwinian fitness. Though the maintenance of ALHS within populations is fairly well understood, little is known regarding the physiological mechanisms that underlie ALHS and how environmental conditions can affect the evolution and expression of these phenotypes. One such ALHS, known as Alba, exists within females of many species in the butterfly genus Colias. Previous works in New World species not only found that female morphs differ in their wing color due to a reallocation of resources away from the synthesis of wing pigments to other areas of development, but also that temperature played an important role in these trade-offs. Here we build on previous work conducted in New World species by measuring life history traits and conducting lipidomics on individuals reared at hot and cold temperatures in the Old World species Colias croceus. Results suggest that the fitness of Alba and orange morphs likely varies with rearing temperature, where Alba females have higher fitness in cold conditions and orange in warm. Additionally shared traits between Old and New World species suggest the Alba mechanism is likely conserved across the genus. Finally, in the cold treatment we observe an intermediate yellow morph that may have decreased fitness due to slower larval development. This cost may manifest as disruptive selection in the field, thereby favoring the maintenance of the two discrete morphs. Taken together these results add insights into the evolution of, and the selection on, the Alba ALHS. Copyright © 2018 Elsevier Ltd. All rights reserved.

Catalog of the George Alan Connor Esperanto Collection.

ERIC Educational Resources Information Center

Smith, Karin, Comp.; Haake, Susan, Comp.

This catalog inventories the collection of books, monographs, serials and periodicals, dictionaries, pamphlets, ephemera, and correspondence concerning Esperanto in the collection of George Alan Connor housed at the University of Oregon Library. Overall, the catalog contains approximately 475 serial entries and 3,000 author entries. Connor was a…

Pigeonholing planetary meteorites: The lessons of misclassification of EET87521 and ALH84001

NASA Technical Reports Server (NTRS)

Lindstrom, M. M.; Treiman, A. H.; Mittlefehldt, D. W.

1994-01-01

The last few years have provided two noteworthy examples of misclassifications of achondritic meteorites because the samples were new kinds of meteorites from planetary rather than asteroidal parent bodies. Basaltic lunar meteorite EET87521 was misclassified as a eucrite and SNC (martian) orthopyroxenite ALH84001 was misclassified as a diogenite. In classifying meteorites we find what we expect: we pigeonhole meteorites into known categories most of which were derived from the more common asteroidal meteorites. But the examples of EET8752 and ALH84001 remind us that planets are more complex than asteroids and exhibit a wider variety of rock types. We should expect variety in planetary meteorites and we need to know how to recognize them when we have them. Our intent here is to show that our asteroidal perspective is inappropriate for planetary meteorites.

Atomic force microscopy imaging of fragments from the Martian meteorite ALH84001

NASA Technical Reports Server (NTRS)

Steele, A.; Goddard, D.; Beech, I. B.; Tapper, R. C.; Stapleton, D.; Smith, J. R.

1998-01-01

A combination of scanning electron microscopy (SEM) and environmental scanning electron microscopy (ESEM) techniques, as well as atomic force microscopy (AFM) methods has been used to study fragments of the Martian meteorite ALH84001. Images of the same areas on the meteorite were obtained prior to and following gold/palladium coating by mapping the surface of the fragment using ESEM coupled with energy-dispersive X-ray analysis. Viewing of the fragments demonstrated the presence of structures, previously described as nanofossils by McKay et al. (Search for past life on Mars--possible relic biogenic activity in martian meteorite ALH84001. Science, 1996, pp. 924-930) of NASA who used SEM imaging of gold-coated meteorite samples. Careful imaging of the fragments revealed that the observed structures were not an artefact introduced by the coating procedure.

Mineral Biomarkers in Martian Meteorite Allan Hills 84001?

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K. L.; Bazylinski, D. A.; Wentworth, S. J.; McKay, D. S.; Golden, D. C.; Gibson, E. K., Jr.; Romanek, C. S.

1998-01-01

The occurrence of fine-grained magnetite in the Fe-rich rims surrounding carbonate globules in the martian meteorite ALH84001, originally described in , have been proposed as fossil remains of primitive martian organisms. Here we report observations on size and shape distributions of magnetites from ALH84001 and compare them to biogenic and inorganic magnetite crystals of terrestrial origin. While some magnetite morphology is not unequivocally diagnostic for its biogenicity, such as cubodial forms of magnetite, which are common in inorganically formed magnetites, other morphologies of magnetite (parallel-epiped or elongated prismatic and arrowhead forms) are more likely signatures of biogenic activity. Some ALH 84001 magnetite particles described below have unique morphology and length-to-width ratios that are indistinguishable from a variety of terrestrial biogenic magnetite and distinct from all known inorganic forms of magnetite.

Covariant C and O Isotope Trends in Some Terrestrial Carbonates and ALH 84001: Possible Linkage Through Similar Formation Processes

NASA Technical Reports Server (NTRS)

Volk, Kathryn E.; Niles, Paul B.; Socki, Richard A.

2011-01-01

Carbonate minerals found on the surface of Mars and in martian meteorites indicate that liquid water has played a significant role in the planet's history. These findings have raised questions regarding the history of the martian hydrosphere and atmosphere as well as the possibility of life. Sunset Crater, Arizona is a dry environment with relatively high evaporation and brief periods of precipitation. This environment resembles Mars and may make Sunset Crater a good analog to martian carbonates. In this study we sought to identify discrete micro-scale isotopic variation within the carbonate crusts in Sunset Crater to see if they resembled the micro-scale isotope variation found in ALH 84001 carbonates. Sunset Crater carbonate formation may be used as a martian analog and ultimately provide insight into carbonate formation in ALH 84001.

KH+Ti co-doped NaAlH4 for high-capacity hydrogen storage

NASA Astrophysics Data System (ADS)

Wang, Ping; Kang, Xiang-Dong; Cheng, Hui-Ming

2005-10-01

A method for preparation of Ti-doped NaAlH4 with high hydrogen capacity was developed, in which the NaH/Al mixture was mechanically milled with a catalytic amount of KH together with metallic Ti. The addition of KH was found to result in a pronounced improvement in the dehydriding performance of the Na3AlH6/NaH+Al step. As a result, the practical cycling hydrogen capacity has been markedly enhanced from 3.3 wt % for the Ti-doped hydride to 4.7 wt % for KH+Ti co-doped material. Moreover, the pronounced enhancement on hydrogen capacity arising upon adding KH was observed to persist in the following dehydrogenation/hydrogenation cycles. Structural investigation shows that the addition of KH has led to a lattice expansion. Moreover, it was found that the enthalpy change of the Na3AlH6/NaH+Al decomposition step underwent a considerable decrease upon adding KH. Therefore, the observed property improvement may be ascribed to a favorable thermodynamic adjustment arising upon the addition of KH.

Effects of acute feed restriction combined with targeted use of increasing luteinizing hormone content of follicle-stimulating hormone preparations on ovarian superstimulation, fertilization, and embryo quality in lactating dairy cows

PubMed Central

Bender, R. W.; Hackbart, K. S.; Dresch, A. R.; Carvalho, P. D.; Vieira, L. M.; Crump, P. M.; Guenther, J. N.; Fricke, P. M.; Shaver, R. D.; Combs, D. K.; Wiltbank, M. C.

2018-01-01

Multiple metabolic and hormonal factors can affect the success of protocols for ovarian superstimulation. In this study, the effect of acute feed restriction and increased LH content in the superstimulatory FSH preparation on numbers of ovulations, fertilization, and embryo quality in lactating dairy cows was evaluated. Two experiments were performed using a Latin square design with treatments arranged as a 2 × 2 factorial: feed restriction (FR; 25% reduction in dry matter intake) compared with ad libitum (AL) feeding, combined with high (H) versus low (L) LH in the last 4 injections of the superstimulatory protocol. As expected, FR decreased circulating insulin concentrations (26.7 vs. 46.0 μU/mL). Two analyses were performed: one that evaluated the complete Latin square in experiment 2 and a second that evaluated only the first periods of experiments 1 and 2. For both analyses, follicle numbers, ovulation rates, and corpora lutea on d 7 were not different. In the first period analysis of experiments 1 and 2, we observed an interaction between feed allowance and amount of LH on fertilization rates, percentage of embryos or oocytes that were quality 1 and 2 embryos, and number of embryos or oocytes that were degenerate. Fertilization rates were greater for the AL-L (89.4%) and FR-H (80.1%) treatments compared with the AL-H (47.9%) and FR-L (59.9%) treatments. Similarly, the proportion of total embryos or oocytes designated as quality 1 and 2 embryos was greater for AL-L (76.7%) and FR-H (73.4%) treatments compared with AL-H (35.6%) and FR-L (47.3%) treatments. In addition, the number of degenerate embryos was decreased for AL-L (1.3) and FR-H (0.4) treatments compared with the AL-H (2.6) and FR-L (2.3) treatments. Thus, cows with either too low (FR-L) or too high (AL-H) insulin and LH stimulation had lesser embryo production after superstimulation because of reduced fertilization rate and increased percentage of degenerate embryos. Therefore, interaction of the gonadotropin content of the superstimulatory preparation with the nutritional program of the donor cow needs to be considered to optimize success of ovarian superstimulatory protocols. PMID:24359829

A mild, near-surface aqueous environment on Noachian Mars preserved in ALH84001

NASA Astrophysics Data System (ADS)

Halevy, I.; Fischer, W. W.; Eiler, J. M.

2011-12-01

Despite widespread evidence for liquid water at the surface of Mars during parts of the Noachian epoch, the temperature of early aqueous environments has been impossible to establish, raising questions of whether Mars' surface was ever warmer than today. This has hindered insight into aqueous alteration processes, which, on the basis of orbital spectroscopy, appear to have been prevalent on Noachian Mars. It is important to understand such processes, as they link the observed secondary mineral assemblages to interactions between primary igneous silicates and the surface environment (atmosphere-hydrosphere). We have addressed this problem by determining the precipitation temperatures of secondary carbonate minerals preserved in the oldest known sample of Mars' crust-the meteorite Allan Hills 84001 (ALH84001). Using carbonate 'clumped' isotope thermometry we have found that the carbonates in ALH84001, which are 3.9-4.0 billion years old, formed at a temperature of ~18±4°C. With temperature known, we used the carbon and oxygen isotopic composition of the carbonates, as constrained by both our measurements and previous acid digestion and ion microprobe studies, to develop a model for their formation process and environment. The observed isotopic variation is best explained by carbonate precipitation out of a gradually evaporating, shallow subsurface aqueous solution (e.g. a regolith aquifer) at near-constant temperatures. Furthermore, on the basis of the isotopic composition of the earliest precipitated carbonates in ALH84001, the volatiles from which they formed (H2O and CO2) came not from depth, but from the early Martian surface. The occurrence of carbonates in other SNC meteorites and as a minor component of Martian dust implies that environments analogous to the one we studied may have been important in generating some of the observed secondary mineral assemblages by interaction between Mars' igneous crust and its atmosphere-hydrosphere.

Astronaut Alan Bean looks over data acquisition camera on Skylab trainer

NASA Image and Video Library

1972-09-01

S72-39256 (1972) --- Astronaut Alan L. Bean, commander for Skylab 3, the second manned Skylab mission, looks over the data acquisition camera mounted on the water tank in the upper level of the Orbital Workshop (OWS) one-G trainer at the Manned Spacecraft Center (MSC). Photo credit: NASA

Astronaut Alan Bean shaves while aboard Skylab

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, uses battery powered shaver while in the crew quarters of the Skylab space station's Orbital Workshop (OWS) crew quarters. This photograph was taken with a 35mm Nikon camera held by one of Bean's fellow crewmen during the 56.5 day second manned Skylab mission in Earth orbit.

Hydrothermal Origin for Carbonate Globules in Martian Meteorite ALH84001: A Terrestrial Analogue from Spitsbergen (Norway)

NASA Technical Reports Server (NTRS)

Treiman, Allan H.; Amundsen, Hans E. F.; Blake, David F.; Bunch, Ted

2002-01-01

Carbonate minerals in the ancient Martian meteorite ALH84001 are the only known solid phases that bear witness to the processing of volatile and biologically critical compounds (CO2, H2O) on early Mars. Similar carbonates have been found in xenoliths and their host basalts from Quaternary volcanic centers in northern Spitsbergen (Norway). These carbonates were deposited by hot (i.e., hydrothermal) waters associated with the volcanic activity. By analogy with the Spitsbergen carbonates, the ALH84001 carbonates were probably also deposited by hot water. Hydrothermal activity was probably common and widespread on Early Mars, which featured abundant basaltic rocks, water as ice or liquid, and heat from volcanos and asteroid impacts. On Earth, descendants of the earliest life forms still prefer hydrothermal environments, which are now shown to have been present on early Mars.

Ca-,Al-rich inclusions in the unique chondrite ALH85085 - Petrology, chemistry, and isotopic compositions

NASA Technical Reports Server (NTRS)

Kimura, Makoto; El-Goresy, Ahmed; Palme, Herbert; Zinner, Ernst

1993-01-01

A comprehensive study is performed for the Ca-,Al-rich inclusions (CAIs) in the unique chondrite ALH85085. The ALH85085 inclusions are smaller (5-80 microns) and more refractory than their counterparts in carbonaceous chondrites. The study includes 42 inclusions for petrography and mineralogy, 15 for bulk major and minor element chemical composition, six for Mg-Al isotopic systematics, 10 for Ca isotopes, nine for Ti isotopes, and six for trace element abundances. In addition, oxygen-isotopic compositions were determined in minerals from a single inclusion. No correlation is found between mineralogy, major element chemistry, and trace element abundances. It is further shown that the high-temperature geochemical behavior of ultrarefractory trace elements is decoupled from that of the major elements Ca and Ti (Ti is correlated with the relatively volatile elements Nb and Yb) implying that perovskite is of only minor importance as carrier of ultrarefractories.

Angiolymphoid hyperplasia with eosinophilia: a clinicopathologic study of 9 cases.

PubMed

Guinovart, R M; Bassas-Vila, J; Morell, L; Ferrándiz, C

2014-03-01

Angiolymphoid hyperplasia with eosinophilia (ALHE) is a rare disease characterized by single or multiple angiomatous lesions typically located on the scalp and the face. We present a retrospective analysis of 9 cases of ALHE. The lesions appeared largely as multiple grouped papules or, in some cases, subcutaneous nodules, located mainly on the scalp, particularly around the ear. We also observed lesions in atypical locations, such as areas of the head other than the scalp, and the shoulder, neck, and forearm. At these sites the lesions had an atypical clinical appearance that made diagnosis difficult; this should be borne in mind in patients with single, well-delimited lesions with a vascular appearance and superficial ulceration or crusting. Surgery was the most common treatment in our series, and even though ALHE is considered a benign condition, recurrence was common. Copyright © 2012 Elsevier España, S.L. and AEDV. All rights reserved.

Extinct Life on Mars: Looking for Traces of Viruses Instead of Bacteria

NASA Astrophysics Data System (ADS)

Ksanfomality, Leonid

The finds in the ALH 84001 meteorite were reported as a sign of traces and fossils of ancient Martian primitive life. Despite many experiments, the issue has not been settled. A study of geochemical data suggests that simple inorganic processes sometimes offer a more plausible explanation of the suspicious structures found in the ALH 84001 meteorite that had been discussed by many authors. A photo of certain micro structures got in the paper of N. Yushkin (Fig. 1) proves the point. (Figure: The inorganic structures in granites.) It is known that viruses possess an ability to survive under very severe external conditions. The Martian biogenic activity (if any) could leave its virus' sign. Thus it could make a sense to look for viruses or even DNA traces both in the body of the ALH 84001 meteorite and on Mars in future space missions instead of traces of the extinct bacteria.

Organic impurity profiling of 3,4-methylenedioxymethamphetamine (MDMA) synthesised from catechol.

PubMed

Heather, Erin; Shimmon, Ronald; McDonagh, Andrew M

2015-03-01

This work examines the organic impurity profile of 3,4-methylenedioxymethamphetamine (MDMA) that has been synthesised from catechol (1,2-dihydroxybenzene), a common chemical reagent available in industrial quantities. The synthesis of MDMA from catechol proceeded via the common MDMA precursor safrole. Methylenation of catechol yielded 1,3-benzodioxole, which was brominated and then reacted with magnesium allyl bromide to form safrole. Eight organic impurities were identified in the synthetic safrole. Safrole was then converted to 3,4-methylenedioxyphenyl-2-propanone (MDP2P) using two synthetic methods: Wacker oxidation (Route 1) and an isomerisation/peracid oxidation/acid dehydration method (Route 2). MDMA was then synthesised by reductive amination of MDP2P. Thirteen organic impurities were identified in MDMA synthesised via Route 1 and eleven organic impurities were identified in MDMA synthesised via Route 2. Overall, organic impurities in MDMA prepared from catechol indicated that synthetic safrole was used in the synthesis. The impurities also indicated which of the two synthetic routes was utilised. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Developments in the Aerosol Layer Height Retrieval Algorithm for the Copernicus Sentinel-4/UVN Instrument

NASA Astrophysics Data System (ADS)

Nanda, Swadhin; Sanders, Abram; Veefkind, Pepijn

2016-04-01

The Sentinel-4 mission is a part of the European Commission's Copernicus programme, the goal of which is to provide geo-information to manage environmental assets, and to observe, understand and mitigate the effects of the changing climate. The Sentinel-4/UVN instrument design is motivated by the need to monitor trace gas concentrations and aerosols in the atmosphere from a geostationary orbit. The on-board instrument is a high resolution UV-VIS-NIR (UVN) spectrometer system that provides hourly radiance measurements over Europe and northern Africa with a spatial sampling of 8 km. The main application area of Sentinel-4/UVN is air quality. One of the data products that is being developed for Sentinel-4/UVN is the Aerosol Layer Height (ALH). The goal is to determine the height of aerosol plumes with a resolution of better than 0.5 - 1 km. The ALH product thus targets aerosol layers in the free troposphere, such as desert dust, volcanic ash and biomass during plumes. KNMI is assigned with the development of the Aerosol Layer Height (ALH) algorithm. Its heritage is the ALH algorithm developed by Sanders and De Haan (ATBD, 2016) for the TROPOMI instrument on board the Sentinel-5 Precursor mission that is to be launched in June or July 2016 (tentative date). The retrieval algorithm designed so far for the aerosol height product is based on the absorption characteristics of the oxygen-A band (759-770 nm). The algorithm has heritage to the ALH algorithm developed for TROPOMI on the Sentinel 5 precursor satellite. New aspects for Sentinel-4/UVN include the higher resolution (0.116 nm compared to 0.4 for TROPOMI) and hourly observation from the geostationary orbit. The algorithm uses optimal estimation to obtain a spectral fit of the reflectance across absorption band, while assuming a single uniform layer with fixed width to represent the aerosol vertical distribution. The state vector includes amongst other elements the height of this layer and its aerosol optical thickness. We will present the development work around the ALH retrieval algorithm in the framework of the Sentinel-4/UVN instrument. The main challenges are highlighted and retrieval simulation results are provided. Also, an outlook towards application of the S4 bread board algorithm to Sentinel-5 Precursor data later this year will be discussed.

A Behavioral Test of Accepting Benefits that Cost Others: Associations with Conduct Problems and Callous-Unemotionality

PubMed Central

Sakai, Joseph T.; Dalwani, Manish S.; Gelhorn, Heather L.; Mikulich-Gilbertson, Susan K.; Crowley, Thomas J.

2012-01-01

Background Youth with conduct problems (CP) often make decisions which value self-interest over the interests of others. Self-benefiting behavior despite loss to others is especially common among youth with CP and callous-unemotional traits (CU). Such behavioral tendencies are generally measured using self- or observer-report. We are unaware of attempts to measure this tendency with a behavioral paradigm. Methods/Principal Findings In our AlAn's (altruism-antisocial) game a computer program presents subjects with a series of offers in which they will receive money but a planned actual charity donation will be reduced; subjects decide to accept or reject each offer. We tested (1) whether adolescent patients with CP (n = 20) compared with adolescent controls (n = 19) differed on AlAn's game outcomes, (2) whether youths with CP and CU differed significantly from controls without CP or CU, and (3) whether AlAn's game outcomes correlated significantly with CP and separately, CU severity. Patients with CP and CU compared with controls without these problems took significantly more money for themselves and left significantly less money in the charity donation; AlAn's game outcomes were significantly correlated with CU, but not CP. Conclusions/Significance In the AlAn's game adolescents with conduct problems and CU traits, compared with controls without CP/CU, are disposed to benefit themselves while costing others even in a novel situation, devoid of peer influences, where anonymity is assured, reciprocity or retribution are impossible, intoxication is absent and when the “other” to be harmed is considered beneficent. AlAn's game outcomes are associated with measures of CU. Results suggest that the AlAn's game provides an objective means of capturing information about CU traits. The AlAn's game, which was designed for future use in the MRI environment, may be used in studies attempting to identify the neural correlates of self-benefiting decision-making. PMID:22558367

Evaluating the Association between Artificial Light-at-Night Exposure and Breast and Prostate Cancer Risk in Spain (MCC-Spain Study).

PubMed

Garcia-Saenz, Ariadna; Sánchez de Miguel, Alejandro; Espinosa, Ana; Valentin, Antonia; Aragonés, Núria; Llorca, Javier; Amiano, Pilar; Martín Sánchez, Vicente; Guevara, Marcela; Capelo, Rocío; Tardón, Adonina; Peiró-Perez, Rosana; Jiménez-Moleón, José Juan; Roca-Barceló, Aina; Pérez-Gómez, Beatriz; Dierssen-Sotos, Trinidad; Fernández-Villa, Tania; Moreno-Iribas, Conchi; Moreno, Victor; García-Pérez, Javier; Castaño-Vinyals, Gemma; Pollán, Marina; Aubé, Martin; Kogevinas, Manolis

2018-04-23

Night shift work, exposure to light at night (ALAN) and circadian disruption may increase the risk of hormone-dependent cancers. We evaluated the association of exposure to ALAN during sleeping time with breast and prostate cancer in a population based multicase-control study (MCC-Spain), among subjects who had never worked at night. We evaluated chronotype, a characteristic that may relate to adaptation to light at night. We enrolled 1,219 breast cancer cases, 1,385 female controls, 623 prostate cancer cases, and 879 male controls from 11 Spanish regions in 2008-2013. Indoor ALAN information was obtained through questionnaires. Outdoor ALAN was analyzed using images from the International Space Station (ISS) available for Barcelona and Madrid for 2012-2013, including data of remotely sensed upward light intensity and blue light spectrum information for each geocoded longest residence of each MCC-Spain subject. Among Barcelona and Madrid participants with information on both indoor and outdoor ALAN, exposure to outdoor ALAN in the blue light spectrum was associated with breast cancer [adjusted odds ratio (OR) for highest vs. lowest tertile, OR=1.47; 95% CI: 1.00, 2.17] and prostate cancer (OR=2.05; 95% CI: 1.38, 3.03). In contrast, those exposed to the highest versus lowest intensity of outdoor ALAN were more likely to be controls than cases, particularly for prostate cancer. Compared with those who reported sleeping in total darkness, men who slept in "quite illuminated" bedrooms had a higher risk of prostate cancer (OR=2.79; 95% CI: 1.55, 5.04), whereas women had a slightly lower risk of breast cancer (OR=0.77; 95% CI: 0.39, 1.51). Both prostate and breast cancer were associated with high estimated exposure to outdoor ALAN in the blue-enriched light spectrum. https://doi.org/10.1289/EHP1837.

Wreath Laying Ceremony for Alan Bean

NASA Image and Video Library

2018-05-30

Members of the news media assemble to cover a ceremony on Wednesday, May 30, 2018, during which a memorial wreath is placed in the Apollo-Saturn V Center of the Kennedy Space Center Visitor Complex honoring former NASA astronaut Alan Bean. In the background is a large mural of a painting by Alan Bean who became an accomplished artist after leaving NASA. Bean was the fourth person to walk on the Moon as lunar module pilot on Apollo 12 in November 1969. He went on to command the 59-day Skylab 3 mission in 1973. He died in Houston on May 26, 2018, at the age of 86.

Photocatalytic oxidation of ammonia by cadmium sulfide/titanate nanotubes synthesised by microwave hydrothermal method.

PubMed

Chen, Y-C; Lo, S-L; Ou, H-H; Chen, C-H

2011-01-01

CdS/Titanate nanotubes (TNTs) were successfully synthesised by a simple, rapid, and reliable microwave hydrothermal method. The CdS nanoparticles synthesised using a 140-W microwave irradiation power at 423 K photodegraded 26% ammonia in water, while the photocatalytic efficiency increased to 52.3% using the synthesised CdS/TNTs composites. The results indicated that the CdS/TNTs photocatalysts possess improved photocatalytic activity than that of CdS or TNTs materials alone.

Atypia on breast core needle biopsies: reproducibility and significance.

PubMed

Darvishian, Farbod; Singh, Baljit; Simsir, Aylin; Ye, Weimin; Cangiarella, Joan F

2009-01-01

This study analyzes the interobserver variability in interpreting atypia on breast core needle biopsies and in each category of atypia calculates the upgrade risk of carcinoma in the subsequent surgical excision. We identified 51 cases of atypia on breast core needle biopsies performed at our institution from January 2003 to August 2006. The atypia was classified into 4 categories: atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), flat epithelial atypia (FEA), and atypia of undetermined significance (AUS). After a tutorial session, these cases were independently reviewed by four pathologists, whose overall multi-rater kappa value for agreement on different categories of atypia was 0.79 (95% CI, 0.69-0.89), which is within the substantial agreement range. The upgrade risk in each category of atypia was as follows: ADH 20% (p = 0.04); ALH 10% (p = 0.6); FEA 16.6% (p = 0.23), and AUS 100% (p = 0.96). Based on our findings, we conclude that follow-up excision should be performed after a diagnosis of ADH. The upgrade risk did not reach statistical significance in ALH or FEA. Although follow-up excision cannot be strongly recommended in ALH and FEA, it should be considered since the upgrade risk is not negligible. Strict adherence to the diagnostic criteria and tutorial sessions can help pathologists to achieve substantial agreement in interpreting atypia on breast core needle biopsies.

Methods for synthesizing alane without the formation of adducts and free of halides

DOEpatents

Zidan, Ragaiy; Knight, Douglas A; Dinh, Long V

2013-02-19

A process is provided to synthesize an alane without the formation of alane adducts as a precursor. The resulting product is a crystallized .alpha.-alane and is a highly stable product and is free of halides.

[Benign proliferative breast disease with and without atypia].

PubMed

Coutant, C; Canlorbe, G; Bendifallah, S; Beltjens, F

2015-12-01

In the last few years, diagnostics of high-risk breast lesions (atypical ductal hyperplasia [ADH], flat epithelial atypia [FEA], lobular neoplasia: atypical lobular hyperplasia [ALH], lobular carcinoma in situ [LCIS], radial scar [RS], usual ductal hyperplasia [UDH], adenosis, sclerosing adenosis [SA], papillary breast lesions, mucocele-like lesion [MLL]) have increased with the growing number of breast percutaneous biopsies. The management of these lesions is highly conditioned by the enlarged risk of breast cancer combined with either an increased probability of finding cancer after surgery, either a possible malignant transformation (in situ or invasive cancer), or an increased probability of developing cancer on the long range. An overview of the literature reports grade C recommendations concerning the management and follow-up of these lesions: in case of ADH, FEA, ALH, LCIS, RS, MLL with atypia, diagnosed on percutaneous biopsies: surgical excision is recommended; in case of a diagnostic based on vacuum-assisted core biopsy with complete disappearance of radiological signal for FEA or RS without atypia: surgical abstention is a valid alternative approved by multidisciplinary meeting. In case of ALH (incidental finding) associated with benign lesion responsible of radiological signal: abstention may be proposed; in case of UDH, adenosis, MLL without atypia, diagnosed on percutaneous biopsies: the concordance of radiology and histopathology findings must be ensured. No data is available to recommend surgery; in case of non-in sano resection for ADH, FEA, ALH, LCIS (except pleomorphic type), RS, MLL: surgery does not seem to be necessary; in case of previous ADH, ALH, LCIS: a specific follow-up is recommended in accordance with HAS's recommendations. In case of FEA and RS or MLL combined with atypia, little data are yet available to differ the management from others lesions with atypia; in case of UDH, usual sclerosing adenosis, RS without atypia, fibro cystic disease: no specific follow-up is recommended in agreement with HAS's recommendations. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Experimental Shock Decomposition of Siderite and the Origin of Magnetite in Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

Bell, Mary Sue

2007-01-01

Shock recovery experiments to determine whether magnetite could be produced by the decomposition of iron-carbonate were initiated. Naturally occurring siderite was first characterized by electron microprobe (EMP), transmission electron microscopy (TEM), Mossbauer spectroscopy, and magnetic susceptibility measurements to be sure that the starting material did not contain detectable magnetite. Samples were shocked in tungsten-alloy holders (W=90%, Ni=6%, Cu=4%) to further insure that any iron phases in the shock products were contributed by the siderite rather than the sample holder. Each sample was shocked to a specific pressure between 30 to 49 GPa. Previously reported results of TEM analyses on 49 GPa experiments indicated the presence of nano-phase spinel-structured iron oxide. Transformation of siderite to magnetite as characterized by TEM was found in the 49 GPa shock experiment. Compositions of most magnetites are greater than 50% Fe sup(+2) in the octahedral site of the inverse spinel structure. Magnetites produced in shock experiments display the same range of single-domain, superparamagnetic sizes (approx. 50 100 nm), compositions (100% magnetite to 80% magnetite-20% magnesioferrite), and morphologies (equant, elongated, euhedral to subhedral) as magnetites synthesized by Golden et al. (2001) or magnetites grown naturally by MV1 magnetotactic bacteria, and as the magnetites in Martian meteorite ALH84001. Fritz et al. (2005) previously concluded that ALH84001 experienced approx. 32 GPa pressure and a resultant thermal pulse of approx. 100 - 110 C. However, ALH84001 contains evidence of local temperature excursions high enough to 1 melt feldspar, pyroxene, and a silica-rich phase. This 49 GPa experiment demonstrates that magnetite can be produced by the shock decomposition of siderite as a result of local heating to greater than 470 C. Therefore, magnetite in the rims of carbonates in Martian meteorite ALH84001 could be a product of shock devolatilization of siderite as well.

Astronaut Alan Bean reads data from book while holding teleprinter tape

NASA Image and Video Library

1973-08-08

SL3-111-1514 (July-September 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, reads data from book in his right hand while holding teleprinter tape in his left hand, in the ward room of the Skylab space station's Orbital Workshop (OWS) crew quarters. This photograph was taken with a 35mm Nikon camera held by one of Bean's fellow crewmen during the 56.5 day second manned Skylab mission in Earth orbit. Photo credit: NASA

The association between artificial light at night and prostate cancer in Gwangju City and South Jeolla Province of South Korea.

PubMed

Kim, Ka Young; Lee, Eunil; Kim, Yun Jeong; Kim, Jinsun

2017-01-01

ABSRACT Exposure to artificial light at night (ALAN) has been reported to be associated with various pathological changes including sleep deprivation, circadian rhythm disruption, and melatonin suppression with increase in various cancers such as breast or prostate cancers. In this study, we sought to elucidate the association between ALAN and prostate cancer in 27 districts within Gwangju City and urban and rural areas from South Jeolla Province in South Korea. We analyzed the correlation between ALAN and the incidence of a range of cancers by Poisson regression analysis, after adjustment for confounding risk factors, such as smoking, drinking, obesity, stress, air pollution (particulate matter <10 μm in diameter), urbanization (proportion of urbanized area), and the cancer screening rate. Interestingly, the incidence of prostate cancer was significantly associated with ALAN (risk ratio = 1.02, p = 0.0369) and urbanization (risk ratio = 1.06, p = 0.0055). In particular, comparing the prostate cancer incidence at 25% and 75% level of ALAN, the risk ratio was 1.726 (12.6 over 7.3, respectively). No significant association was observed between ALAN and other cancers, including stomach, esophageal, liver, pancreatic, laryngeal, lung and tracheal, bladder, and brain and central nervous system cancers, as well as lymphoma and multiple myeloma. In conclusion, this study shows that a high incidence of prostate cancer may be independently associated with light pollution and urbanization, which represent significant factors in the rapid process of industrialization of South Korea.

Isotopic Composition of Trapped and Cosmogenic Noble Gases in Several Martian Meteorites

NASA Technical Reports Server (NTRS)

Garrison, Daniel H.; Bogard, Donald D.

1997-01-01

Isotopic abundances of the noble gases were measured in the following Martian meteorites: two shock glass inclusions from EET79001, shock vein glass from Shergotty and Y793605, and whole rock samples of ALH84001 and QUE94201. These glass samples, when combined with literature data on a separate single glass inclusion from EET79001 and a glass vein from Zagami, permit examination of the isotopic composition of Ne, Ar, Kr, and Xe trapped from the Martian atmosphere in greater detail. The isotopic composition of Martian Ne, if actually present in these glasses, remains poorly defined. The Ar-40/Ar-36 ratio of Martian atmospheric Ar may be much less than the ratio measured by Viking and possibly as low as approx. 1900. The atmospheric Ar-36/Ar-38 ratio is less than or equal to 4.0. Martian atmospheric Kr appears to be enriched in lighter isotopes by approx. 0.4%/amu compared to both solar wind Kr and to the Martian composition previously reported. The Martian atmospheric Ar-36/Xe-132 and Kr-84/Xe-132 Xe elemental ratios are higher than those reported by Viking by factors of approx. 3.3 and approx. 2.5, respectively. Cosmogenic gases indicate space exposure ages of 13.9 +/- 1 Myr for ALH84001 and 2.7 +/- 0.6 Myr for QUE94201. Small amounts of Ne-21 produced by energetic solar protons may be present in QUE94201, but are not present in ALH84001 or Y793605. The space exposure age for Y793605 is 4.9 +/- 0.6 Myr and appears to be distinctly older than the ages for basaltic shergottites.

The role of chemoprevention in modifying the risk of breast cancer in women with atypical breast lesions.

PubMed

Coopey, Suzanne B; Mazzola, Emanuele; Buckley, Julliette M; Sharko, John; Belli, Ahmet K; Kim, Elizabeth M H; Polubriaginof, Fernanda; Parmigiani, Giovanni; Garber, Judy E; Smith, Barbara L; Gadd, Michele A; Specht, Michelle C; Guidi, Anthony J; Roche, Constance A; Hughes, Kevin S

2012-12-01

Women with atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), lobular carcinoma in situ (LCIS), and severe ADH are at increased risk of breast cancer, but a systematic quantification of this risk and the efficacy of chemoprevention in the clinical setting is still lacking. The objective of this study is to evaluate a woman's risk of breast cancer based on atypia type and to determine the effect of chemoprevention in decreasing this risk. Review of 76,333 breast pathology reports from three institutions within Partners Healthcare System, Boston, from 1987 to 2010 using natural language processing was carried out. This approach identified 2,938 women diagnosed with atypical breast lesions. The main outcome of this study is breast cancer occurrence. Of the 2,938 patients with atypical breast lesions, 1,658 were documented to have received no chemoprevention, and 184/1,658 (11.1 %) developed breast cancer at a mean follow-up of 68 months. Estimated 10-year cancer risks were 17.3 % with ADH, 20.7 % with ALH, 23.7 % with LCIS, and 26.0 % with severe ADH. In a subset of patients treated from 1999 on (the chemoprevention era), those who received no chemoprevention had an estimated 10-year breast cancer risk of 21.3 %, whereas those treated with chemoprevention had a 10-year risk of 7.5 % (p < 0.001). Chemoprevention use significantly reduced breast cancer risk for all atypia types (p < 0.05). The risk of breast cancer with atypical breast lesions is substantial. Physicians should counsel patients with ADH, ALH, LCIS, and severe ADH about the benefit of chemoprevention in decreasing their breast cancer risk.

Analyses at High Spatial Resolution of Organic Molecules in Extraterrestrial Samples: Two-Step Laser Mass Spectrometry: Search for Polycyclic Aromatic Hydrocarbons in Antarctic Meteorite and Micrometeorite Samples

NASA Technical Reports Server (NTRS)

Zare, Richard N.

1998-01-01

Perhaps the best way to summarize the past three-year grant period is to cite the publications and present a brief synopsis of each: 1. "Indigenous Polycyclic Aromatic Hydrocarbon Molecules in Circumstellar Graphite Grains." Bulk C-12/C-13 isotope ratios observed in some graphite grains extracted from primitive meteorites point strongly to a circumstellar origin. By applying our technique of microprobe two-step laser desorption laser ionization mass spectrometry ((mu)L(sup 2)MS) to individual circumstellar graphite grains we have measured the C-12/C-13 isotope ratio of various polycyclic aromatic hydrocarbons (PAHS) found in these grains. 2. "Deuterium Enrichments in Cluster IDPS," Large enrichments in the D/H isotope ratios in IDPs likely arise from the preservation of presolar molecules. 3. "Evidence for thermalization of surface-disorder molecules at heating rates of 10(exp 8) K/s". A careful study of the ((mu)L(sup 2)MS) of aniline-d(sub 7) from a single-crystal surface (0001) of sapphire (al2O3) shows that all measured properties are consistent with a thermal mechanism for desorption. 4. "Search for past life on Mars; possible relic biogenic activity in Martian meteorite ALH 84001. The authors examined the Martian meteorite ALH 84001 and found several lines of evidence compatible with existence of past primitive (single-cell) life on early Mars. 5. "Microprobe two-step laser mass spectrometry as an analytical tool for meteorite samples". THis paper presents a comprehensive review of (mu)L(sup 2)MS and how this technique can be applied to meteoritic samples. 6. "Indigenous polycyclic aromatic hydrocarbons in circumstellar graphite grains from primitive meteorites". The C-12/C-13 isotope ratios were measured for PAHs in a total of 89 spherical graphite grains. 7. "Observation of indigenous polycyclic aromatic hydrocarbons in "Giant" carbonaceous antarctic micrometeorites." The (mu)L(sup 2)MS method was used to establish the nature and distribution of PAHs in fragments of fifteen (approx. 200 microns) carbonaceous antarctic micrometeorites (AMMs). 8. "Evidence for the extraterrestrial origin of polycyclic aromatic hydrocarbons in the Martian meteorite ALH 84001" We have undertaken additional contamination studies of ALH 84001.

Morphometric and kinematic sperm subpopulations in split ejaculates of normozoospermic men

PubMed Central

Santolaria, Pilar; Soler, Carles; Recreo, Pilar; Carretero, Teresa; Bono, Araceli; Berné, José M; Yániz, Jesús L

2016-01-01

This study was designed to analyze the sperm kinematic and morphometric subpopulations in the different fractions of the ejaculate in normozoospermic men. Ejaculates from eight normozoospermic men were collected by masturbation in three fractions after 3–5 days of sexual abstinence. Analyses of sperm motility by computer-assisted sperm analysis (CASA-Mot), and of sperm morphometry by computer-assisted sperm morphometry analysis (CASA-Morph) using fluorescence were performed. Clustering and discriminant procedures were performed to identify sperm subpopulations in the kinematic and morphometric data obtained. Clustering procedures resulted in the classification of spermatozoa into three kinematic subpopulations (slow with low ALH [35.6% of all motile spermatozoa], with circular trajectories [32.0%], and rapid with high ALH [32.4%]), and three morphometric subpopulations (large-round [33.9% of all spermatozoa], elongated [32.0%], and small [34.10%]). The distribution of kinematic sperm subpopulations was different among ejaculate fractions (P < 0.001), with higher percentages of spermatozoa exhibiting slow movements with low ALH in the second and third portions, and with a more homogeneous distribution of kinematic sperm subpopulations in the first portion. The distribution of morphometric sperm subpopulations was also different among ejaculate fractions (P < 0.001), with more elongated spermatozoa in the first, and of small spermatozoa in the third, portion. It is concluded that important variations in the distribution of kinematic and morphometric sperm subpopulations exist between ejaculate fractions, with possible functional implications. PMID:27624985

Astronaut Alan Bean flies the Astronaut Maneuvering Equipment

NASA Image and Video Library

1973-08-27

SL3-107-1215 (27 Aug. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the forward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. One of his fellow crewmen took this photograph with a 35mm Nikon camera. Bean is strapped into the back mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). The dome area is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA

Astronaut Alan Bean flies the Astronaut Maneuvering Equipment

NASA Image and Video Library

1973-08-18

SL3-108-1304 (July-September 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the forward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. Bean is strapped in to the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). This ASMU experiment is being done in shirt sleeves. The dome area where the experiment is conducted is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA

Multispectroscopic (FTIR, XPS, and TOFMS-TPD) Investigation of the Core-Shell Bonding in Sonochemically-Prepared Aluminum Nanoparticles Capped with Oleic Acid (Preprint)

DTIC Science & Technology

2010-04-01

dimethylethylamine and a titanium (IV) isopropoxide catalyst were added to the solution. The concentrations of the alane complex and titanium catalyst in...public release 3.0 METHODS, ASSUMPTIONS, AND PROCEDURES 3.1 Materials Alane N,N-dimethylethylamine in a 0.4 M toluene solution, titanium (IV... isopropoxide (98%), oleic acid (99%), dodecane (99% and anhydrous), and oleyl alcohol (99%) were all obtained from Aldrich and used as received

Chains of magnetite crystals in the meteorite ALH84001: Evidence of biological origin

PubMed Central

Friedmann, E. Imre; Wierzchos, Jacek; Ascaso, Carmen; Winklhofer, Michael

2001-01-01

The presence of magnetite crystal chains, considered missing evidence for the biological origin of magnetite in ALH84001 [Thomas-Keprta, K. L., Bazylinski, D. A., Kirschvink, J. L., Clemett, S. J., McKay, D. S., Wentworth, S. J., Vali, H., Gibson, E. K., Jr., & Romanek, C. S. (2000) Geochim. Cosmochim. Acta 64, 4049–4081], is demonstrated by high-power stereo backscattered scanning electron microscopy. Five characteristics of such chains (uniform crystal size and shape within chains, gaps between crystals, orientation of elongated crystals along the chain axis, flexibility of chains, and a halo that is a possible remnant of a membrane around chains), observed or inferred to be present in magnetotactic bacteria but incompatible with a nonbiological origin, are shown to be present. Although it is unlikely that magnetotactic bacteria were ever alive in ALH84001, decomposed remains of such organisms could have been deposited in cracks in the rock while it was still on the surface on Mars. PMID:11226212

Sublimation: A Mechanism for the Enrichment of Organics in Antarctic Ice

NASA Technical Reports Server (NTRS)

Becker, Luann; McDonald, Gene D.; Glavin, Daniel P.; Bada, Jeffrey L.; Bunch, Theodore E.; Chang, Sherwood (Technical Monitor)

1997-01-01

Recent analyses of the carbonate globules present in the Martian meteorite ALH84001 have detected polycyclic aromatic hydrocarbons (PAHs) at the ppm level. The distribution of PAHs observed in ALH84001 was interpreted as being inconsistent with a terrestrial origin and were claimed to be indigenous to the meteorite, perhaps derived from an ancient Martian biota. However, Becker et al., have examined PAHs in the Martian meteorite EETA79001, in several Antarctic carbonaceous chondrites and Antarctic Allan Hills Ice and detected many of the same PAHs found in ALH84001. The reported presence of L-amino acids of apparent terrestrial origin in the EETA79001 druse material, suggests that this meteorite is contaminated with terrestrial/extraterrestrial organics probably derived from Antarctic ice meltwater that had percolated through the meteorite. The detection of PAHs and L-amino acids in these Martian meteorites suggests that despite storage in the Antarctic ice, selective changes of certain chemical and mineralogical phases has occurred.

Combined pulsed dye and CO2 lasers in the treatment of angiolymphoid hyperplasia with eosinophilia.

PubMed

Sagi, Lior; Halachmi, Shlomit; Levi, Assi; Amitai, Dan Ben; Enk, Claes D; Lapidoth, Moshe

2016-08-01

Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon dermatosis of unknown etiology that manifests as characteristic red nodules and papules with a predilection for the scalp and periauricular region. Treatment is required for both esthetic and functional reasons, as lesions may ulcerate and bleed. Many treatment approaches have been reported, including excision, systemic medical approaches, topical or intralesional therapies, and non-invasive modalities including cryotherapy, electrosurgery, and laser. Treatments have exhibited variable efficacy, and the recurrence rate is 100 %. We report the combination of pulsed dye laser and CO2 laser in the treatment of ALHE in 14 patients. All patients exhibited clinical response after a mean of 2.4 ± 0.4 treatment sessions. The clinical efficacy of the combined treatment, together with its well-tolerated nature, render the use of pulsed dye laser in combination with CO2 laser, a viable treatment for debulking ALHE lesions. Ongoing maintenance treatments are needed to due to the high degree of relapse.

Amino Acids in the Antarctic Martian Meteorite MIL03346

NASA Technical Reports Server (NTRS)

Glavin, D. P.; Aubrey, A.; Dworkin, J. P.; Botta, O.; Bada, J. L.

2005-01-01

The report by McKay et al. that the Martian meteorite ALH84001 contains evidence for life on Mars remains controversial. Of central importance is whether ALH84001 and other Antarctic Martian meteorites contain endogenous organic compounds. In any investigation of organic compounds possibly derived from Mars it is important to focus on compounds that play an essential role in biochemistry as we know it and that have properties such as chirality which can be used to distinguish between biotic versus abiotic origins. Amino acids are one of the few compounds that fulfill these requirements. Previous analyses of the Antarctic Martian meteorites ALH84001 and EETA79001 have shown that these meteorites contain low levels of terrestrial amino acid contamination derived from Antarctic ice meltwater. Here we report preliminary amino acid investigations of a third Antarctic Martian meteorite MIL03346 which was discovered in Antarctica during the 2003-04 ANSMET season. Additional information is included in the original extended abstract

High Incidence of Breast Cancer in Light-Polluted Areas with Spatial Effects in Korea.

PubMed

Kim, Yun Jeong; Park, Man Sik; Lee, Eunil; Choi, Jae Wook

2016-01-01

We have reported a high prevalence of breast cancer in light-polluted areas in Korea. However, it is necessary to analyze the spatial effects of light polluted areas on breast cancer because light pollution levels are correlated with region proximity to central urbanized areas in studied cities. In this study, we applied a spatial regression method (an intrinsic conditional autoregressive [iCAR] model) to analyze the relationship between the incidence of breast cancer and artificial light at night (ALAN) levels in 25 regions including central city, urbanized, and rural areas. By Poisson regression analysis, there was a significant correlation between ALAN, alcohol consumption rates, and the incidence of breast cancer. We also found significant spatial effects between ALAN and the incidence of breast cancer, with an increase in the deviance information criterion (DIC) from 374.3 to 348.6 and an increase in R2 from 0.574 to 0.667. Therefore, spatial analysis (an iCAR model) is more appropriate for assessing ALAN effects on breast cancer. To our knowledge, this study is the first to show spatial effects of light pollution on breast cancer, despite the limitations of an ecological study. We suggest that a decrease in ALAN could reduce breast cancer more than expected because of spatial effects.

Isospecific propylene polymerization with in situ generated bis(phenoxy-amine)zirconium and hafnium single site catalysts.

PubMed

Makio, Haruyuki; Prasad, Aitha Vishwa; Terao, Hiroshi; Saito, Junji; Fujita, Terunori

2013-07-07

Bis(phenoxy-imine) Zr and Hf complexes were activated with (i)Bu3Al or (i)Bu2AlH in conjunction with Ph3CB(C6F5)4 and tested as catalysts for propylene polymerization with emphasis on the enantioselectivity of the isospecific species and the single site polymerization characteristics. The isoselective species was identified as the in situ generated bis(phenoxy-amine) complex whose isoselectivity was sensitive to subtle changes in ligand structure. By employing specific substituents at certain key positions the isotacticity reached an extremely high level comparable to high-end commercial isotactic polypropylenes (Tm > 160 °C). Single site polymerization characteristics depended upon the efficiency and selectivity of the in situ imine reduction which is sensitive to the substituent on the imine nitrogen and the reaction conditions. By using (i)Bu2AlH as a reducing agent, quantitative imine reduction can be achieved with a stoichiometric amount of the reducing agent. This lower alkylaluminum loading is beneficial for the catalyst and significantly enhances the polymerization activity and the molecular weight of the resultant polymer.

Wreath Laying Ceremony for Alan Bean

NASA Image and Video Library

2018-05-30

Associate Kennedy Space Center Director Kelvin Manning joins guests in a ceremony on Wednesday, May 30, 2018, honoring former NASA astronaut Alan Bean. As lunar module pilot on Apollo 12, Bean was the fourth person to walk on the Moon in November 1969. He went on to command the 59-day Skylab 3 mission in 1973. He died in Houston on May 26, 2018, at the age of 86.

Biologically synthesised silver nanoparticles from three diverse family of plant extracts and their anticancer activity against epidermoid A431 carcinoma.

PubMed

Nayak, Debasis; Pradhan, Sonali; Ashe, Sarbani; Rauta, Pradipta Ranjan; Nayak, Bismita

2015-11-01

Biological synthesis of silver nanoparticles is a cost effective natural process where the phytochemicals specifically phenols, flavonoids and terpenoids present in the plant extracts act as capping and reducing agent. Due to their nano size regime the silver nanoparticles may directly bind to the DNA of the pathogenic bacterial strains leading to higher antimicrobial activity. In the current study silver nanoparticles were synthesised using plant extracts from different origin Cucurbita maxima (petals), Moringa oleifera (leaves) and Acorus calamus (rhizome). The synthesised nanoparticles were characterized by UV-visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), field emission scanning electron microscopy (Fe-SEM) and Fourier transform infrared spectroscopy (FTIR). Highly crystalline, roughly spherical and cuboidal silver nanoparticles of 30-70 nm in size were synthesised. The nanoparticles provided strong antimicrobial activity against pathogenic strains. The effect of the synthesised nanoparticles against A431 skin cancer cell line was tested for their toxicity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) dye. The IC50 values of 82.39±3.1, 83.57±3.9 and 78.58±2.7 μg/ml were calculated for silver nanoparticles synthesised by C. maxima, M. oleifera and A. calamus respectively. Copyright © 2015 Elsevier Inc. All rights reserved.

Astronaut Alan Bean reads data from book while holding teleprinter tape

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, reads data from book in his right hand while holding teleprinter tape in his left hand, in the ward room of the Skylab space station's Orbital Workshop (OWS) crew quarters. This photograph was taken with a 35mm Nikon camera held by one of Bean's fellow crewmen during the 56.5 day second manned Skylab mission in Earth orbit.

Astronaut Owen Garriott trims hair of Astronaut Alan Bean

NASA Image and Video Library

1973-08-19

SL3-108-1292 (19 Aug. 1973) --- Scientist-astronaut Owen K. Garriott, Skylab 3 science pilot, trims the hair of astronaut Alan L. Bean, commander, in this onboard photograph from the Skylab Orbital Workshop (OWS) in Earth orbit. Astronaut Jack R. Lousma, pilot, took this picture with a 35mm Nikon camera. Bean holds a vacuum hose to gather in loose hair. The crew of the second manned Skylab flight went on to successfully complete 59 days aboard the Skylab space station cluster in Earth orbit. Photo credit: NASA

Flat epithelial atypia on core needle biopsy, must we surgically excise?

PubMed

Acott, A A; Mancino, A T

2016-12-01

Breast flat epithelial atypia (FEA) often coexists with more aggressive pathology and excision is currently recommended when diagnosed by core needle biopsy (CNB). Recent studies suggest isolated FEA has a low association with carcinoma and may warrant close surveillance. A radiology database containing 2189 breast CNB was reviewed for isolated FEA or FEA in combination with atypical pathology. 79 patients had FEA. There were 48/79 with isolated FEA and 31/79 concomitant FEA with ADH, ALH, or LCIS. 46 subsequent excisional biopsies of isolated FEA resulted: benign 38/46, ADH 5/46, LCIS 2/46, DCIS 1/46. Concomitant FEA + ADH/ALH/LCIS group resulted: benign 26/31, DCIS 3/31, DCIS and LCIS 1/31, tubular carcinoma 1/31. DCIS/invasive cancer on excision in the FEA + ADH group is 5/31 versus 1/46 for isolated FEA (p 0.0489). Findings support literature suggesting isolated FEA has a low association with carcinoma. These patients may not require surgical excision, but instead have close surveillance. Based on the higher cancer incidence in FEA combined with ADH, ALH, LCIS, or residual microcalcifications, we still recommend surgical excision. Breast flat epithelial atypia (FEA) often coexists with more aggressive pathology and surgical excision is currently recommended when diagnosed by core needle biopsy. Recent studies have suggested isolated FEA has a low association with carcinoma and these patients may warrant close surveillance. Isolated FEA has a low association with carcinoma in our series. These patients may not require surgical excision, but instead have close surveillance. Published by Elsevier Inc.

Outdoor artificial light at night, obesity, and sleep health: Cross-sectional analysis in the KoGES study.

PubMed

Koo, Yong Seo; Song, Jin-Young; Joo, Eun-Yeon; Lee, Heon-Jeong; Lee, Eunil; Lee, Sang-kun; Jung, Ki-Young

2016-01-01

Obesity is a common disorder with many complications. Although chronodisruption plays a role in obesity, few epidemiological studies have investigated the association between artificial light at night (ALAN) and obesity. Since sleep health is related to both obesity and ALAN, we investigated the association between outdoor ALAN and obesity after adjusting for sleep health. We also investigated the association between outdoor ALAN and sleep health. This cross-sectional survey included 8526 adults, 39-70 years of age, who participated in the Korean Genome and Epidemiology Study. Outdoor ALAN data were obtained from satellite images provided by the US Defense Meteorological Satellite Program. We obtained individual data regarding outdoor ALAN; body mass index; depression; and sleep health including sleep duration, mid-sleep time, and insomnia; and other demographic data including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking status and consumption of caffeine or alcohol before sleep. A logistic regression model was used to investigate the association between outdoor ALAN and obesity. The prevalence of obesity differed significantly according to sex (women 47% versus men 39%, p < 0.001) and outdoor ALAN (high 55% versus low 40%, p < 0.001). Univariate logistic regression analysis revealed a significant association between high outdoor ALAN and obesity (odds ratio [OR] 1.24, 95% confidence interval [CI] 1.14-1.35, p < 0.001). Furthermore, multivariate logistic regression analyses showed that high outdoor ALAN was significantly associated with obesity after adjusting for age and sex (OR 1.25, 95% CI 1.14-1.37, p < 0.001) and even after controlling for various other confounding factors including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking, consumption of caffeine or alcohol before sleep, delayed sleep pattern, short sleep duration and habitual snoring (OR 1.20, 95% CI 1.06-1.36, p = 0.003). The findings of our study provide epidemiological evidence that outdoor ALAN is significantly related to obesity.

ALH85085: a unique volatile-poor carbonaceous chondrite with possible implications for nebular fractionation processes

USGS Publications Warehouse

Grossman, J.N.; Rubin, A.E.; MacPherson, G.J.

1988-01-01

Allan Hills 85085 is a unique chondrite with affinities to the Al Rais-Renazzo clan of carbonaceous chondrites. Its constituents are less than 50 ??m in mean size. Chondrules and microchondrules of all textures are present; nonporphyritic chondrules are unusually abundant. The mean compositions of porphyritic, nonporphyritic and barred olivine chondrules resemble those in ordinary chondrites except that they are depleted in volatile elements. Ca-, Al-rich inclusions are abundant and largely free of nebular alteration; they comprise types similar to those in CM and CO chondrites, as well as unique types. Calcium dialuminate occurs in several inclusions. Metal, silicate and sulfide compositions are close to those in CM-CO chondrites and Al Rais and Renazzo. C1-chondrite clasts and metal-rich "reduced" clasts are present, but opaque matrix is absent. Siderophile abundances in ALH85085 are extremely high (e.g., Fe Si = 1.7 ?? solar), and volatiles are depleted (e.g., Na Si = 0.25 ?? solar, S Si = 0.03 ?? solar). Nonvolatile lithophile abundances are similar to those in Al Rais, Renazzo, and CM and CO chondrites. ALH85085 agglomerated when temperatures in the nebula were near 1000 K, in the same region where Renazzo, Al Rais and the CI chondrites formed. Agglomeration of high-temperature material may thus be a mechanism by which the fractionation of refractory lithophiles occurred in the nebula. Chondrule formation must have occurred at high temperatures when clumps of precursors were small. After agglomeration, ALH85085 was annealed and lightly shocked. C1 and other clasts were subsequently incorporated during late-stage brecciation. ?? 1988.

Evolving concepts in the management of lobular neoplasia.

PubMed

Anderson, Benjamin O; Calhoun, Kristine E; Rosen, Eric L

2006-05-01

Lobular neoplasia broadly defines the spectrum of changes within the lobule, ranging from atypical lobular hyperplasia (ALH) to lobular carcinoma in situ (LCIS). This continuum of lesions is associated with an increased risk for developing subsequent invasive breast cancer, with the magnitude of that risk corresponding to the degree of proliferative change. The associated risk for developing invasive breast cancer after a diagnosis of lobular neoplasia is multicentric, bilateral, and equal in both breasts. Lobular neoplasia itself may transform into invasive carcinoma, although the frequency of this occurrence is unknown. Thus, lobular neoplasia is a risk factor for invasive breast cancer and may be a precursor lesion in unusual circumstances. The management of ALH and LCIS depends on the setting in which they are encountered. When ALH and LCIS are diagnosed after core needle breast biopsy, wire localization for surgical excision is required for definitive diagnosis because rates of histologic underestimation approach those of atypical ductal hyperplasia (ADH). When diagnosed on surgical biopsy, ALH and LCIS generally do not require further intervention, even when present at a surgical margin. However, bilateral breast cancer risk must be considered, especially when patients have a family history of breast cancer. In selected situations, bilateral prophylactic mastectomy with or without reconstruction may be considered when atypical hyperplasia or LCIS is diagnosed. Although this reduces risk for developing subsequent breast carcinoma by 90%, patients selected for prophylactic mastectomy represent a small subgroup of lobular neoplasia patients and generally have other risk factors, such as strong family history or evidence of genetic predisposition.

Wreath Laying Ceremony for Alan Bean

NASA Image and Video Library

2018-05-30

A memorial wreath placed in the Apollo-Saturn V Center of the Kennedy Space Center Visitor Complex on Wednesday, May 30, 2018, honors former NASA astronaut Alan Bean. He was the fourth person to walk on the Moon as lunar module pilot on Apollo 12 in November 1969. He went on to command the 59-day Skylab 3 mission in 1973. He died in Houston on May 26, 2018, at the age of 86.

Wreath Laying Ceremony for Alan Bean

NASA Image and Video Library

2018-05-30

Therrin Protze, COO at the Kennedy Space Center Visitor Complex, speaks in the Apollo-Saturn V Center during a ceremony on Wednesday, May 30, 2018, honoring former NASA astronaut Alan Bean. As lunar module pilot on Apollo 12, Bean was the fourth person to walk on the Moon in November 1969. He went on to command the 59-day Skylab 3 mission in 1973. He died in Houston on May 26, 2018, at the age of 86.

Passive remote sensing of altitude and optical depth of dust plumes using the oxygen A and B bands: First results from EPIC/DSCOVR at Lagrange-1 point

NASA Astrophysics Data System (ADS)

Xu, Xiaoguang; Wang, Jun; Wang, Yi; Zeng, Jing; Torres, Omar; Yang, Yuekui; Marshak, Alexander; Reid, Jeffrey; Miller, Steve

2017-07-01

We presented an algorithm for inferring aerosol layer height (ALH) and optical depth (AOD) over ocean surface from radiances in oxygen A and B bands measured by the Earth Polychromatic Imaging Camera (EPIC) on the Deep Space Climate Observatory (DSCOVR) orbiting at Lagrangian-1 point. The algorithm was applied to EPIC imagery of a 2 day dust outbreak over the North Atlantic Ocean. Retrieved ALHs and AODs were evaluated against counterparts observed by Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), Moderate Resolution Imaging Spectroradiometer, and Aerosol Robotic Network. The comparisons showed 71.5% of EPIC-retrieved ALHs were within ±0.5 km of those determined from CALIOP and 74.4% of EPIC AOD retrievals fell within a ± (0.1 + 10%) envelope of MODIS retrievals. This study demonstrates the potential of EPIC measurements for retrieving global aerosol height multiple times daily, which are essential for evaluating aerosol profile simulated in climate models and for better estimating aerosol radiative effects.

Influence of feeding supplements of almond hulls and ensiled citrus pulp on the milk production, milk composition, and methane emissions of dairy cows.

PubMed

Williams, S R O; Chaves, A V; Deighton, M H; Jacobs, J L; Hannah, M C; Ribaux, B E; Morris, G L; Wales, W J; Moate, P J

2018-03-01

Almond hulls and citrus pulp have been fed to dairy cows with variable responses for milk production, but no information exists on their effect on enteric methane emissions. This experiment examined the effects of dietary supplementation with either almond hulls or ensiled citrus pulp on the milk yield, milk composition, and enteric methane emissions of dairy cows. Thirty-two Holstein dairy cows in mid lactation were offered 1 of 3 diets over a 28-d experiment. Twelve cows received a control (CON) diet, 10 cows a diet containing almond hulls (ALH), and 10 cows a diet containing ensiled citrus pulp (CIT). All cows were offered 6.0 kg of dry matter (DM)/d of crushed corn, 2.0 kg of DM/d of cold-pressed canola, and 0.2 kg of DM/d of a mineral mix. In addition, cows fed the CON diet were offered 14.5 kg of DM/d of alfalfa cubes; cows fed the ALH diet were offered 10.5 kg of DM/d of alfalfa cubes and 4.0 kg of DM/d of almond hulls; and cows on the CIT diet were offered 11.5 kg of DM/d of alfalfa cubes and 3.0 kg of DM/d of ensiled citrus pulp. Milk yield was measured daily and milk composition was measured on 4 d of each week. Individual cow methane emissions were measured by a sulfur hexafluoride tracer technique on d 24 to 28 of the experiment. The mean milk yield of cows fed the CON diet (27.4 kg/d) was greater than the mean milk yield of cows fed the ALH diet (24.6 kg/cow per day), whereas the mean milk yield of cows fed the CIT diet (26.2 kg/cow per day) was not different from the mean milk yield from cows fed the other 2 diets. Dietary treatment did not influence the concentrations of milk fat, protein, and lactose or fat yields, but the mean protein yield from cows fed the CON diet (0.87 kg/d) was greater than that from cows fed the ALH diet (0.78 kg/d) but not different to those fed the CIT diet (0.85 kg/d). In general, we found no differences in the proportion of individual fatty acids in milk. The mean pH of ruminal fluid from cows offered the CON diet was not different to the pH in the ruminal fluids of cows offered the ALH or the CIT diets. The mean methane emissions (g/d) and yields (g/kg of DM intake) were not influenced by dietary treatment. These findings indicate that, although almond hulls and ensiled citrus pulp can be used as a low-cost feed supplement, almond hulls did negatively affect milk production and neither inhibited enteric methane emissions. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Elusive silane-alane complex [Si-H⋅⋅⋅Al]: isolation, characterization, and multifaceted frustrated Lewis pair type catalysis.

PubMed

Chen, Jiawei; Chen, Eugene Y-X

2015-06-01

The super acidity of the unsolvated Al(C6F5)3 enabled isolation of the elusive silane-alane complex [Si-H⋅⋅⋅Al], which was structurally characterized by spectroscopic and X-ray diffraction methods. The Janus-like nature of this adduct, coupled with strong silane activation, effects multifaceted frustrated-Lewis-pair-type catalysis. When compared with the silane-borane system, the silane-alane system offers unique features or clear advantages in the four types of catalytic transformations examined in this study, including: ligand redistribution of tertiary silanes into secondary and quaternary silanes, polymerization of conjugated polar alkenes, hydrosilylation of unactivated alkenes, and hydrodefluorination of fluoroalkanes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Workshop on the Issue Martian Meteorites: Where do we Stand and Where are we Going?

NASA Technical Reports Server (NTRS)

1998-01-01

The presentations in this workshop discuss the composition of Martian meteorites. Many of the talks were on a specific meteorite, i.e., Allan Hills 84001 (ALH84001). The discovery earlier of carbonates in ALH84001 lead some researchers to suggest that there was evidence of martian life. Other possible explanations for this phenomena are given. Other papers discuss methods to sterilize martian samples, the existence of water on Mars, the facilities of the Meteorite Processing Laboratory at Johnson Space Center, comparative analyses of geologic processes and the gathering of meteorites.

A Graphics Environment Supporting the Rapid Prototyping of Pictorial Cockpit Displays

DTIC Science & Technology

1986-12-01

0 - niDi cO 3 FIL .OF I A GRAPHICS ENVIRONMENT SUPPORTING THE RAPID PROTOTYPING OF PICTORIAL COCKPIT DISPLAYS THESIS Alan J. Braaten Captain, USAF...COCKPIT DISPLAYS THESIS Alan J. Braaten Captain, USAF AFIT/GCS/IA/86D- 1 Appram:ed for public release; distribution unlimited AFIT/GCS/MA/80- 1 A...GRAPHICS ENVIROWNT SUPPORTING THE RAPID PROTOTYPING OF PICTORIAL COCKPIT DISPLAYS THESIS Preented to the Faculty Of the School of Engineering of the Air

Astronaut Alan Shepard receives MASA Distinguished Service award

NASA Image and Video Library

1961-05-07

S88-31387 (8 May 1961) --- President John F. Kennedy (left) congratulates NASA's Distinguished Service Medal Award recipient astronaut Alan B. Shepard Jr. in a Rose Garden ceremony on May 8, 1961, at the White House. Vice-President Lyndon B. Johnson, NASA Administrator James E. Webb and several NASA astronauts are in the background. Three days earlier, Shepard made history with a 15-minute suborbital space mission in the Freedom 7, Mercury-Redstone 3 spacecraft. Photo credit: NASA

Investigating the Role of Akt1 in Prostate Cancer Development Through Phosphorylation-Dependent Regulation of Skp2 Stability and Oncogenic Function

DTIC Science & Technology

2010-09-01

ubiquitin ligase. Science 2001, 294(5540):173-177. 7. Strohmaier H, Spruck CH, Kaiser P, Won KA , Sangfelt O, Reed SI: Human F-box protein hCdc4 targets...Anders H. Berg,1 Alan Tseng,1 Bo Zhai,2 Shavali Shaik,1 Eric Bennett,3 Adriana E. Tron,4 Jessica A. Gasser,1 Alan Lau,1 Steven P. Gygi,2 J. Wade Harper

Astronaut Alan Bean flies the Astronaut Maneuvering Equipment

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the foreward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. Bean is strapped in to the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). This ASMU exerperiment is being done in shirt sleeves. The dome area where the experiment is conducted is about 22 feet in diameter and 19 feet from top to bottom.

Astronaut Alan Bean flies the Astronaut Maneuvering Equipment

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the forward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. Bean is strapped in to the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). This ASMU exerperiment is being done in shirt sleeves. The dome area where the experiment is conducted is about 22 feet in diameter and 19 feet from top to bottom.

On the fate of laser-produced NH 2 in a constrained pulsed expansion of trimethylamine alane and NH 3

NASA Astrophysics Data System (ADS)

Demchuk, Alexander; Cahill, John J.; Simpson, Steven; Koplitz, Brent

2001-11-01

The effects of both 193 nm radiation and NH 3 on an expansion of trimethylamine alane (TMAA) have been studied. In neat TMAA, 193 nm radiation induces small but significant clustering. When NH 3 is introduced in the absence of 193 nm photons, no visible reaction occurs. However, when NH 3 is introduced along with 193 nm photons, the H 3Al:N(CH 3) 3 parent molecule is completely replaced by H 3AlNH 2. Moreover, the clustering channels observed with neat TMAA disappear. The apparent stability or inertness of the R 3MNH 2 (R=H, CH 3 or C 2H 5; M=Ga or Al) species in a variety of metal nitride reactive environments is discussed.

Candidates source regions of martian meteorites as identified by OMEGA/MEx

NASA Astrophysics Data System (ADS)

Ody, A.; Poulet, F.; Quantin, C.; Bibring, J.-P.; Bishop, J. L.; Dyar, M. D.

2015-09-01

The objective of this study is to identify and map spectral analogues of some key martian meteorites (basaltic shergottites Los Angeles, Shergotty, QUE 94201, lherzolitic shergottite ALH A77005, Nakhla, Chassigny and the orthopyroxenite ALH 84001) in order to localize terrain candidates for their source regions. We develop a best fit procedure to reproduce the near-infrared (NIR) spectral properties of the martian surface as seen by the hyperspectral imaging spectrometer OMEGA/MEx from the NIR spectra of the martian meteorites. The fitting process is tested and validated, and Root Mean Square (RMS) global maps for each meteorite are obtained. It is found that basaltic shergottites have NIR spectral properties the most representative of the martian surface with the best spectral analogues found in early Hesperian volcanic provinces. Sites with spectral properties similar to those of ALH A77005 are scarce. They are mainly localized in olivine-bearing regions such as Nili Fossae and small Noachian/early Hesperian terrains. The only plausible source region candidate for Chassigny is the Nili Patera caldera dated to 1.6 Ga. Widespread spectral analogues for the ALH 84001 meteorite are found northeast of Syrtis Major and northwest of the Hellas basin. While this distribution is in agreement with the low-calcium-pyroxene-rich composition and old age (4.1 Ga) of this meteorite, the modal mineralogy of these candidates is not consistent with that of this meteorite. No convincing spectral analogue is found for the Amazonian-aged Nakhla meteorite suggesting that its olivine/high-calcium-pyroxene-rich composition could be representative of the Amazonian terrains buried under dust. Finally, some young rayed craters are proposed as possible candidates for source craters of the studied martian meteorites.

Surgical upgrade rate of breast atypia to malignancy: An academic center's experience and validation of a predictive model.

PubMed

Linsk, Ali; Mehta, Tejas S; Dialani, Vandana; Brook, Alexander; Chadashvili, Tamuna; Houlihan, Mary Jane; Sharma, Ranjna

2018-03-01

Atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), and lobular carcinoma in situ (LCIS) are commonly seen on breast core needle biopsy (CNB). Many institutions recommend excision of these lesions to exclude malignancy. A retrospective chart review was performed on patients who had ADH, ALH, or LCIS on breast CNB from 1/1/08 to 12/31/10 who subsequently had surgical excision of the biopsy site. Study objectives included determining upgrade to malignancy at surgical excision, identification of predictors of upgrade, and validation of a recently published predictive model. Clinical and demographic factors, pathology, characteristics of the biopsy procedure and visible residual lesion were recorded. T test and chi-squared test were used to identify predictors. Classification tree was used to predict upgrade. 151 patients had mean age of 53 years. The mean maximum lesion size on imaging was 11 mm. The primary atypia was ADH in 63.6%, ALH in 27.8%, and LCIS in 8.6%. 16.6% of patients had upgrade to malignancy, with 72% DCIS and 28% invasive carcinoma. Risk factors for upgrade included maximum lesion size (P = .002) and radiographic presence of residual lesion (P = .001). A predictive model based on these factors had sensitivity 78%, specificity 80% and AUC = 0.88. Validating a published nomogram with our data produced accuracy figures (AUC = 0.65) within published CI of 0.63-0.82. In CNB specimens containing ADH, ALH, or LCIS, initial lesion size and presence of residual lesion are predictors of upgrade to malignancy. A validated model may be helpful in developing patient management strategies. © 2017 Wiley Periodicals, Inc.

House Dust Endotoxin and Peripheral Leukocyte Counts: Results from Two Large Epidemiologic Studies

PubMed Central

Carnes, Megan U.; Salo, Päivi M.; Wilkerson, Jesse; Cohn, Richard D.; King, Debra; Hoppin, Jane A.; Sandler, Dale P.; Travlos, Greg; London, Stephanie J.; Thorne, Peter S.; Zeldin, Darryl C.

2017-01-01

Background: The peripheral leukocyte count is a biomarker of inflammation and is associated with human all-cause mortality. Although causes of acute leukocytosis are well-described, chronic environmental determinants of leukocyte number are less well understood. Objectives: We investigated the relationship between house dust endotoxin concentration and peripheral leukocyte counts in human subjects. Methods: The endotoxin–leukocyte relationship was evaluated by linear regression in the National Health and Nutrition Examination Survey (NHANES) 2005–2006 (n=6,254) and the Agricultural Lung Health Study (ALHS; n=1,708). In the ALHS, we tested for a gene [Toll-like Receptor 4 (TLR4), encoding the endotoxin receptor]-by-environment interaction in the endotoxin–leukocyte relationship using regression models with an interaction term. Results: There is a statistically significant, positive association between endotoxin concentration and total leukocyte number [estimated change, 0.186×103/μL (95% CI: 0.070, 0.301×103/μL) per 10-fold change in endotoxin; p=0.004) in the NHANES. Similar positive associations were found for monocytes, lymphocytes, and neutrophils. Stratified analyses revealed possible effect modification by asthma and chronic obstructive pulmonary disease. We observed similar associations in the ALHS. For total leukocytes, there was suggestive evidence in the ALHS of a gene-by-environment interaction for minor allele carrier status at the TLR4 haplotype defined by rs4986790 and rs4986791 (interaction p=0.15). Conclusions: This is, to our knowledge, the first report of an association between house dust endotoxin and leukocyte count in a national survey. The finding was replicated in a farming population. Peripheral leukocyte count may be influenced by residential endotoxin exposure in diverse settings. https://doi.org/10.1289/EHP661 PMID:28599265

Seasonal associations with urban light pollution for nocturnally migrating bird populations.

PubMed

La Sorte, Frank A; Fink, Daniel; Buler, Jeffrey J; Farnsworth, Andrew; Cabrera-Cruz, Sergio A

2017-11-01

The spatial extent and intensity of artificial light at night (ALAN) has increased worldwide through the growth of urban environments. There is evidence that nocturnally migrating birds are attracted to ALAN, and there is evidence that nocturnally migrating bird populations are more likely to occur in urban areas during migration, especially in the autumn. Here, we test if urban sources of ALAN are responsible, at least in part, for these observed urban associations. We use weekly estimates of diurnal occurrence and relative abundance for 40 nocturnally migrating bird species that breed in forested environments in North America to assess how associations with distance to urban areas and ALAN are defined across the annual cycle. Migratory bird populations presented stronger than expected associations with shorter distances to urban areas during migration, and stronger than expected association with higher levels of ALAN outside and especially within urban areas during migration. These patterns were more pronounced during autumn migration, especially within urban areas. Outside of the two migration periods, migratory bird populations presented stronger than expected associations with longer distances to urban areas, especially during the nonbreeding season, and weaker than expected associations with the highest levels of ALAN outside and especially within urban areas. These findings suggest that ALAN is associated with higher levels of diurnal abundance along the boundaries and within the interior of urban areas during migration, especially in the autumn when juveniles are undertaking their first migration journey. These findings support the conclusion that urban sources of ALAN can broadly effect migratory behavior, emphasizing the need to better understand the implications of ALAN for migratory bird populations. © 2017 John Wiley & Sons Ltd.

An Analysis of the President’s Budgetary Proposals for Fiscal Year 2008

DTIC Science & Technology

2007-03-01

PROPOSALS IN THE PRESIDENT’S 2008 BUDGET 53The evidence amassed so far is consistent with the view that dividend taxation affects firms ’ payout policies ...3 (2005), pp. 791– 833; Jeffrey Brown, Nellie Liang, and Scott Weisbenner, “Execu- tive Financial Incentives and Payout Policy : Firm Responses to the...by the firm . For an overview of those issues, see Alan Auerbach, “Taxation and Corporate Financial Policy ,” in Alan Auerbach and Martin Feldstein

Wreath Laying Ceremony for Alan Bean

NASA Image and Video Library

2018-05-30

Kennedy Space Center Director Bob Cabana speaks to guests in the Apollo-Saturn V Center at the spaceport's visitor complex on Wednesday, May 30, 2018. The ceremony is honoring the memory of former NASA astronaut Alan Bean. As lunar module pilot on Apollo 12, Bean was the fourth person to walk on the Moon in November 1969. He went on to command the 59-day Skylab 3 mission in 1973. He died in Houston on May 26, 2018, at the age of 86.

Breaking News: Public Affairs and the 21st Century

DTIC Science & Technology

2002-04-01

Web Sites 35 Table 10. Information on PA Web Sites 35 v Acknowledgements By way of acknowledgements, I want to thank Mr. Richard McGraw; Ms...Press, 3:38. 4 Carl H. Builder, �Service Identities and Behavior�, American Defense Policy, 7th ed, Peter L. Hayes, Brenda J. Vallance , and Alan R...Maritime Strategy, in �Services Identities and Behaviors,� in American Defense Policy, 7th ed, Peter L. Hayes, Brenda J. Vallance , and Alan R. Van

Effects of artificial light at night on human health: A literature review of observational and experimental studies applied to exposure assessment.

PubMed

Cho, YongMin; Ryu, Seung-Hun; Lee, Byeo Ri; Kim, Kyung Hee; Lee, Eunil; Choi, Jaewook

2015-01-01

It has frequently been reported that exposure to artificial light at night (ALAN) may cause negative health effects, such as breast cancer, circadian phase disruption and sleep disorders. Here, we reviewed the literature assessing the effects of human exposure to ALAN in order to list the health effects of various aspects of ALAN. Several electronic databases were searched for articles, published through August 2014, related to assessing the effects of exposure to ALAN on human health; these also included the details of experiments on such exposure. A total of 85 articles were included in the review. Several observational studies showed that outdoor ALAN levels are a risk factor for breast cancer and reported that indoor light intensity and individual lighting habits were relevant to this risk. Exposure to artificial bright light during the nighttime suppresses melatonin secretion, increases sleep onset latency (SOL) and increases alertness. Circadian misalignment caused by chronic ALAN exposure may have negative effects on the psychological, cardiovascular and/or metabolic functions. ALAN also causes circadian phase disruption, which increases with longer duration of exposure and with exposure later in the evening. It has also been reported that shorter wavelengths of light preferentially disturb melatonin secretion and cause circadian phase shifts, even if the light is not bright. This literature review may be helpful to understand the health effects of ALAN exposure and suggests that it is necessary to consider various characteristics of artificial light, beyond mere intensity.

A low temperature transfer of ALH84001 from Mars to Earth.

PubMed

Weiss, B P; Kirschvink, J L; Baudenbacher, F J; Vali, H; Peters, N T; Macdonald, F A; Wikswo, J P

2000-10-27

The ejection of material from Mars is thought to be caused by large impacts that would heat much of the ejecta to high temperatures. Images of the magnetic field of martian meteorite ALH84001 reveal a spatially heterogeneous pattern of magnetization associated with fractures and rock fragments. Heating the meteorite to 40 degrees C reduces the intensity of some magnetic features, indicating that the interior of the rock has not been above this temperature since before its ejection from the surface of Mars. Because this temperature cannot sterilize most bacteria or eukarya, these data support the hypothesis that meteorites could transfer life between planets in the solar system.

Computer-Assisted Sperm Analysis (CASA) parameters and their evolution during preparation as predictors of pregnancy in intrauterine insemination with frozen-thawed donor semen cycles.

PubMed

Fréour, Thomas; Jean, Miguel; Mirallié, Sophie; Dubourdieu, Sophie; Barrière, Paul

2010-04-01

To study the potential of CASA parameters in frozen-thawed donor semen before and after preparation on silica gradient as predictors of pregnancy in IUI with donor semen cycles. CASA parameters were measured in thawed donor semen before and after preparation on a silica gradient in 132 couples undergoing 168 IUI cycles with donor semen. The evolution of these parameters throughout this process was calculated. The relationship with cycle outcome was then studied. Clinical pregnancy rate was 18.4% per cycle. CASA parameters on donor semen before or after preparation were not significantly different between pregnancy and failure groups. However, amplitude of lateral head displacement (ALH) of spermatozoa improved in all cycles where pregnancy occurred, thus predicting pregnancy with a sensitivity of 100% and a specificity of 20%. Even if CASA parameters do not seem to predict pregnancy in IUI with donor semen cycles, their evolution during the preparation process should be evaluated, especially for ALH. However, the link between ALH improvement during preparation process and pregnancy remains to be explored. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

77 FR 37074 - License Amendment Request From the Alan J. Blotcky Reactor Facility

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-20

... the Alan J. Blotcky Reactor Facility AGENCY: Nuclear Regulatory Commission. ACTION: Notice of... section of this document. FOR FURTHER INFORMATION CONTACT: Theodore Smith, Project Manager, Reactor... provided the first time that a document is referenced. The Alan J. Blotcky Reactor Facility Decommissioning...

Lattice damage and Al-metal precipitation in 2.5 MeV-electron-irradiated AlH3

NASA Astrophysics Data System (ADS)

Zogal, O. J.; Vajda, P.; Beuneu, F.; Pietraszko, A.

1998-04-01

AlH3 powder was bombarded with energetic electrons at 20 K and at room temperature and investigated by EPR, NMR, X-ray diffractometry, and microwave dielectric-constant measurements. The EPR spectra of the irradiated powder and of a selected single crystal cuboid of ˜ {10^{ - 1}} mm edge show a complex asymmetric line centered at g = 2.009, with a Curie-like temperature dependence, attributed to radiation-induced color centers and/or their agglomerates. At the same time, the grains, which have become shiny black after irradiation, exhibit an increase of both the real and the imaginary part of ɛ. 27Al-NMR spectra of the irradiated powder present a Knight-shifted line at 1600(50) ppm, close to the position of bulk metallic Al, and corresponding to a concentration of c(Al) ˜ {10^{ - 1}}. In addition, the main hydride line differs from that before irradiation, demonstrating an alteration of environmental symmetry. The irradiation induces also a change in shape and width of the 1H-NMR line, another indication of symmetry change in the lattice. Finally, a refined X-ray single-crystal structure analysis of the irradiated cuboid indicates a change of structure from trigonal R -3 c to R -3, with a loss of mirror symmetry for the two Al sites caused by the introduction of Al-defects in the vicinity of one of them.

Low-pressure Structural Modification of Aluminum Hydride

DTIC Science & Technology

2011-02-01

Acknowledgments Use of the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory ( BNL ) was supported by the U.S. Department of Energy...National Synchrotron Light Source (NSLS) of Brookhaven National Laboratory ( BNL ). The spectral resolution of ±4 cm–1 was used for all IR measurements...12 List of Symbols, Abbreviations, and Acronyms Al aluminum AlH3 aluminum hydride BNL Brookhaven National Laboratory EOS equation of

Alan Wright | NREL

Science.gov Websites

, Alan is the technical lead and project leader for the Advanced Controls Task. Under Alan's direction , NREL has become a world leader in the development and testing of advanced controls for wind turbine load mitigation and enhanced energy capture and performed the world's first field tests of advanced

Alan Bean Art Exhibit

NASA Image and Video Library

2009-07-19

NASA Apollo 12 Astronaut and Artist Alan Bean gives remarks at the opening of the exhibit "Alan Bean: Painting Apollo, First Artist on Another World" at the National Air and Space Museum, Monday, July 20, 2009 in Washington. The show opening coincided with the 40th anniversary celebration of Apollo. Photo Credit: (NASA/Bill Ingalls)

Inhibitory actions of synthesised polyamine spider toxins and their analogues on Ca2+-activated Cl- currents recorded from cultured DRG neurones from neonatal rats.

PubMed

Sutton, K G; Stapleton, S R; Scott, R H

1998-07-24

The whole cell variant of the patch clamp technique was used to investigate the actions of polyamine spider toxins and their analogues on high voltage-activated Ca2+ currents and Ca2+-activated Cl- currents (I(Cl(Ca))). The actions of synthesised FTX (putative natural toxin from the American funnel web spider), sFTX-3.3, Orn-FTX-3.3, Lys-FTX-3.3, and argiotoxin-636 on cultured dorsal root ganglion neurones from neonatal rats were investigated. Synthesised FTX (1 microM) inhibited I(Cl(Ca)) but did not inhibit high voltage-activated Ca2+ currents. In contrast, sFTX-3.3 (10 microM) inhibited both high voltage-activated Ca2+ currents and the associated I(Cl(Ca)) in near equal proportions. Argiotoxin-636 (1-10 microM) inhibited I(Cl(Ca)) evoked by Ca2+ entry through voltage-activated channels and by intracellular photorelease of Ca2+ from a caged precursor DM-nitrophen. This data indicates that synthesised FTX and argiotoxin-636 directly inhibit Ca2+-activated Cl- channels. In conclusion, the potency of polyamines as non-selective inhibitors of Ca2+ channels and Ca2+-activated Cl- channels is in part determined by the presence of a terminal arginine and this may involve an interaction between terminal guanidino groups and Ca2+ binding sites.

Revisiting the ALA/N (alpha-lipoic acid/low-dose naltrexone) protocol for people with metastatic and nonmetastatic pancreatic cancer: a report of 3 new cases.

PubMed

Berkson, Burton M; Rubin, Daniel M; Berkson, Arthur J

2009-12-01

The authors, in a previous article, described the long-term survival of a man with pancreatic cancer and metastases to the liver, treated with intravenous alpha-lipoic acid and oral low-dose naltrexone (ALA/N) without any adverse effects. He is alive and well 78 months after initial presentation. Three additional pancreatic cancer case studies are presented in this article. At the time of this writing, the first patient, GB, is alive and well 39 months after presenting with adenocarcinoma of the pancreas with metastases to the liver. The second patient, JK, who presented to the clinic with the same diagnosis was treated with the ALA/N protocol and after 5 months of therapy, PET scan demonstrated no evidence of disease. The third patient, RC, in addition to his pancreatic cancer with liver and retroperitoneal metastases, has a history of B-cell lymphoma and prostate adenocarcinoma. After 4 months of the ALA/N protocol his PET scan demonstrated no signs of cancer. In this article, the authors discuss the poly activity of ALA: as an agent that reduces oxidative stress, its ability to stabilize NF(k)B, its ability to stimulate pro-oxidant apoptosic activity, and its discriminative ability to discourage the proliferation of malignant cells. In addition, the ability of lowdose naltrexone to modulate an endogenous immune response is discussed. This is the second article published on the ALA/N protocol and the authors believe the protocol warrants clinical trial.

Alan Bean Art Exhibit

NASA Image and Video Library

2009-07-19

Guest view works of art by NASA Apollo 12 Astronaut and Artist Alan Bean during the opening of the show "Alan Bean: Painting Apollo, First Artist on Another World" at the National Air and Space Museum, Monday, July 20, 2009 in Washington. The show opening coincided with the 40th anniversary celebration of Apollo. Photo Credit: (NASA/Bill Ingalls)

Sodium Chloride and Water Transport in the Medullary Thick Ascending Limb of Henle. EVIDENCE FOR ACTIVE CHLORIDE TRANSPORT

PubMed Central

Rocha, Antonino S.; Kokko, Juha P.

1973-01-01

Transport of NaCl and water was examined in the rabbit medullary thick ascending limb of Henle (ALH) by perfusing isolated segments of these nephrons in vitro. Osmotic water permeability was evaluated by perfusing tubules against imposed osmotic gradients. In these experiments the net transport of fluid remained at zero when segments of thick ALH were perfused with isotonic ultrafiltrate in a bath of rabbit serum in which the serum osmolality was increased by the addition of either 239±8 mosmol/liter of raffinose or 232±17 mosmol of NaCl indicating that the thick ascending limb of Henle is impermeant to osmotic flow of water. When these tubules were perfused at slow rates with isosmolal ultrafiltrate of same rabbit serum as used for the bath, the effluent osmolality was consistently lowered to concentrations less than the perfusate and the bath. That this decrease in collected fluid osmolality represented salt transport was demonstrated in a separate set of experiments in which it was shown that the sodium and chloride concentrations decreased to 0.79±0.02 and 0.77±0.02 respectively when compared with the perfusion fluid concentrations. In each instance the simultaneously determined transtubular potential difference (PD) revealed the lumen to be positive with the magnitude dependent on the perfusion rate. At flow rates above 2 nl·min-1, the mean transtubular PD was stable and equal to 6.70±0.34 mv. At stop-flow conditions this PD became more positive. Ouabain and cooling reversibly decreased the magnitude of this PD. The transtubular PD remained positive, 3.3±0.2 mV, when complete substitution of Na by choline was carried out in both the perfusion fluid and the bathing media. These results are interpreted to indicate that the active transport process is primarily an electrogenic chloride mechanism. The isotopic permeability coefficient for Na was 6.27±0.38 × 10-5 cm·s-1 indicating that the thick ALH is approximately as permeable to Na as the proximal convoluted tubule. The chloride permeability coefficient for the thick ALH was 1.06±0.12 × 10-5 cm·s-1 which is significantly less than the chloride permeability of the proximal tubule. These data demonstrate that the medullary thick ascending limb of Henle is water impermeable while having the capacity for active outward solute transport as a consequence of an electrogenic chloride pump. The combination of these characteristics allows this segment to generate a dilute tubular fluid and participate as the principal energy source for the overall operation of the countercurrent multiplication system. Images PMID:4685086

Wreath Laying Ceremony for Alan Bean

NASA Image and Video Library

2018-05-30

A memorial wreath placed in the Apollo-Saturn V Center of the Kennedy Space Center Visitor Complex on Wednesday, May 30, 2018, honors former NASA astronaut Alan Bean. He was the fourth person to walk on the Moon as lunar module pilot on Apollo 12 in November 1969. He went on to command the 59-day Skylab 3 mission in 1973. In the background is a large mural of a painting by Bean who became an accomplished artist after leaving NASA. He died in Houston on May 26, 2018, at the age of 86.

Astronaut Alan Bean flies the Astronaut Maneuvering Equipment

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the foreward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. Bean is strapped in to the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). He is wearing a pressure suit for this run of the M509 experiment, but other ASMU tests are done in shirt sleeves. The dome area where the experiment is conducted is about 22 feet in diameter and 19 feet from top to bottom.

Astronaut Alan Bean flies the Astronaut Maneuvering Equipment in the OWS

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment, as seen in this photographic reproduction taken from a television transmission made by a color television camera in the Orbital Workshop (OWS) of the Skylab space station in Earth orbit. Bean is strapped into the back-mounted, hand-controlled Automatically stabilized Maneuvering Unit (ASMU). The M509 exercise was in the forward dome area of the OWS. THe dome area is about 22 feet in diameter and 19 feet form top to bottom.

Density functional theory studies on the solvent effects in Al(H2O)63+ water-exchange reactions: the number and arrangement of outer-sphere water molecules.

PubMed

Liu, Li; Zhang, Jing; Dong, Shaonan; Zhang, Fuping; Wang, Ye; Bi, Shuping

2018-03-07

Density functional theory (DFT) calculations combined with cluster models are performed at the B3LYP/6-311+G(d,p) level for investigating the solvent effects in Al(H 2 O) 6 3+ water-exchange reactions. A "One-by-one" method is proposed to obtain the most representative number and arrangement of explicit H 2 Os in the second hydration sphere. First, all the possible ways to locate one explicit H 2 O in second sphere (N m ' = 1) based on the gas phase structure (N m ' = 0) are examined, and the optimal pathway (with the lowest energy barrier) for N m ' = 1 is determined. Next, more explicit H 2 Os are added one by one until the inner-sphere is fully hydrogen bonded. Finally, the optimal pathways with N m ' = 0-7 are obtained. The structural and energetic parameters as well as the lifetimes of the transition states are compared with the results obtained with the "Independent-minimum" method and the "Independent-average" method, and all three methods show that the pathway with N m ' = 6 may be representative. Our results give a new idea for finding the representative pathway for water-exchange reactions in other hydrated metal ion systems.

Contribution of Organic Material to the Stable Isotope Composition of Some Terrestrial Carbonates as Analogs for Martian Processes

NASA Technical Reports Server (NTRS)

Socki, Richard A.; Gibson, Everett K., Jr.; Bissada, K. K.

2005-01-01

Understanding the isotopic geochemistry of terrestrial carbonate formation is essential to understanding the evolution of the Martian atmosphere, hydrosphere, and potential biosphere. Carbonate minerals, in particular, are important secondary minerals for interpreting past aqueous environments, as illustrated by the carbonates present in ALH84001 [1]. Models for the history of Mars suggest that the planet was warmer, wetter, and possessed a greater atmospheric pressure within the first billion years as compared to present conditions [2],[3],[4], and likely had an active hydrologic cycle. Morse and Marion [5] point out that associated with this hydrologic cycle would be the active chemical weathering of silicate minerals and thus consumption of atmospheric CO2 and deposition of carbonate and silica. It is during this warmer and wetter period of Martian history that surface and/or near-surface conditions would be most favorable for harboring possible microbiological life. Carbonates within ALH84001 offer evidence that fluids were present at 3.9 Gy on Mars [6]. A more through understanding of the effects of aqueous weathering and the potential contribution of organic compounds on the isotopic composition of Martian carbonate minerals can be gained by studying some terrestrial occurrences of carbonate rocks.

Bacterial mineralization patterns in basaltic aquifers: implications for possible life in martian meteorite ALH84001

NASA Technical Reports Server (NTRS)

Thomas-Keprta, K. L.; McKay, D. S.; Wentworth, S. J.; Stevens, T. O.; Taunton, A. E.; Allen, C. C.; Coleman, A.; Gibson, E. K. Jr; Romanek, C. S.

1998-01-01

To explore the formation and preservation of biogenic features in igneous rocks, we have examined the organisms in experimental basaltic microcosms using scanning and transmission electron microscopy. Four types of microorganisms were recognized on the basis of size, morphology, and chemical composition. Some of the organisms mineralized rapidly, whereas others show no evidence of mineralization. Many mineralized cells are hollow and do not contain evidence of microstructure. Filaments, either attached or no longer attached to organisms, are common. Unattached filaments are mineralized and are most likely bacterial appendages (e.g., prosthecae). Features similar in size and morphology to unattached, mineralized filaments are recognized in martian meteorite ALH84001.

Remanent magnetic properties of unbrecciated eucrites

NASA Technical Reports Server (NTRS)

Cisowski, Stanley M.

1991-01-01

This study examines the remanent magnetic properties of five unbrecciated eucrites, ranging from the coarse-grained cumulate Moore County to the quenched melt rock ALH 81001 in order to assess the strength of the magnetic field associated with their parent body during their formation. Two of the meteorites are judged as unlikely to have preserved their primary thermal remanence because of large variations in subsample remanence intensity and direction (Ibitira), and lack of NRM resistance to AF and thermal demagnetization (PCA 82502). The lack of a strong (greater than 0.01 mT) magnetizing field during their cooling on the eucrite parent body is inferred from the low normalized NRM intensities for subsamples of ALH 81001 and Yamato 791195.

Astronaut Alan Shepard is rescued by helicopter at end of MR-3 flight

NASA Image and Video Library

1961-05-05

S88-31376 (5 May 1961) --- Astronaut Alan B. Shepard Jr., pilot of the Mercury-Redstone 3 (MR-3) suborbital spaceflight, is retrieved by a helicopter from the USS Lake Champlain during recovery operations in the western Atlantic Ocean. Shepard and the Mercury spacecraft designated the ?Freedom 7? (floating in water below) were flown to the deck of the recovery ship within 11 minutes of splashdown. MR-3 was the United States? first manned space mission. The spacecraft attained a maximum speed of 5,180 miles per hour, reached an altitude of 116 1/2 statute miles, and landed 302 statute miles downrange from Cape Canaveral, Florida. The suborbital mission lasted 15 minutes and 22 seconds. Photo credit: NASA or National Aeronautics and Space Administration

Perspective of Family Members of Transitions to Alternative Levels of Care in Anglo-Saxon Countries.

PubMed

Merla, C; Wickson-Griffiths, A; Kaasalainen, S; Dal Bello-Haas, V; Banfield, L; Hadjistavropoulos, T; Di Sante, E

2018-01-01

This scoping review explores circumstances surrounding the decision about, and eventual experience of, transitioning older adults into alternative levels of housing (ALH), such as long-term care. This topic is examined from a family member perspective, given their exposure and involvement in the care of older adult relatives during this transitional period. The scoping review methodology is based on the framework of Arksey and O'Malley and subsequent recommendations from Levac, Colquhoun, and O'Brien. Approximately 470 articles were reviewed covering the period between 2000 and November 2014; 37 articles met inclusion criteria. A temporal organization of themes was used to describe the experiences of family members in the pretransition, active transition, and posttransition periods of moving older adult relatives into ALH. This paper highlights the transitional period as a time of crisis, with a lack of planning, support, and transparent discussion. This study identifies a need for future research on the potential benefits of family support groups, interim transitional housing options, different models of ALH, changing roles in the posttransition period, and the need for a comprehensive list of housing options for older adults. Results have the potential to inform policy/practice and improve the lives of older adults and their family.

LU-HF Age and Isotope Systematics of ALH84001

NASA Technical Reports Server (NTRS)

Righter, M.; Lapen, T. J.; Brandon, A. D.; Beard, B. L.; Shafer, J. T.; Peslier, A. H.

2009-01-01

Allan Hills (ALH) 84001 is an orthopyroxenite that is unique among the Martian meteorites in having the oldest inferred crystallization age (approx..4.5 to 4.0 Gyr) [e.g., 1-6 and references therein 7]. Its ancient origin makes this stone a critical constraint on early history of Mars, in particular the evolution of different planetary crust and mantle reservoirs. However, because there is significant variability in reported crystallization ages, determination of initial isotope compositions is imprecise making assessment of planetary reservoirs difficult. Here we report a new Lu-Hf mineral isochron age, initial Hf-176/Hf-177 isotope composition, and inferred Martian mantle source compositions for ALH84001 that place constraints on longlived source reservoirs for the enriched shergottite suite of Martian meteorites including Shergotty, Zagami, NWA4468, NWA856, RBT04262, LAR06319, and Los Angeles. Sm-Nd isotope analyses are under way for the same mineral aliquots analyzed for Lu-Hf. The Lu-Hf system was utilized because Lu and Hf are both lithophile and refractory and are not easily redistributed during short-lived thermal pulses associated with shock metamorphism. Moreover, chromite has relatively modest Hf concentrations with very low Lu/Hf ratios [9] yielding tight constraints on initial Hf-176/Hf-177 isotope compositions

[Angiolymphoid hyperplasia with eosinophilia with bilateral involvement of the lacrimal glands].

PubMed

Baráková, Drahomíra; Sâch, Josef; Kuchynka, Pavel; Rêdinová, Magdalena; Kocur, Ivo

2002-05-01

Angiolymphoid hyperplasia with eosinophilia (ALHE) and Kimura's disease are two rarely occurring disorders very similar to each other; however, they are individual nosological entities. For a long time they were considered as a single disease due to the frequency of similar characteristics. The majority of authors have recently considered these diseases as two individual entities with some reciprocal specifications, both clinical as well as morphological. We report on the case of a 76-year old male white European who had suffered for more than six years from subcutaneous tumour formations in different parts of the body. Eyelid oedema on the right side with palpable resistance under the upper temporal edge of the orbit initially occurred five years after the first symptoms of the disease. A similar finding occurred on the left side after eight months. The tumours on both sides were surgically removed and sent for histological analysis. A unilateral recurrence of the finding appeared after one year, followed by surgical intervention and histological examination. Tumour infiltrate in the first two orbita excisions was topically related to lacrimal gland structures; these structures were not found in the third excision. The case was histologically diagnosed as ALHE despite some similar characteristics with Kimura's disease. The diagnosis of ALHE was histologically supported, especially by the absence of lymphatic follicle formations and fibrotisation in the infiltrate, and the identification of the appearance of epitheloid up to histiocytoid of proliferating endothelium, which forms small lumens. The diagnosis of ALHE was additionally supported by the fact that the incidence of Kimura's disease in white Europeans is very rare. According to our findings, both entities overlap one another, even in some characteristics considered to be distinguishing. The question arises, therefore, whether the strict separation of these nosological entities can indeed be determined with one hundred percent accuracy.

DNA methylation in a Scottish family multiply affected by bipolar disorder and major depressive disorder.

PubMed

Walker, Rosie May; Christoforou, Andrea Nikie; McCartney, Daniel L; Morris, Stewart W; Kennedy, Nicholas A; Morten, Peter; Anderson, Susan Maguire; Torrance, Helen Scott; Macdonald, Alix; Sussmann, Jessika Elizabeth; Whalley, Heather Clare; Blackwood, Douglas H R; McIntosh, Andrew Mark; Porteous, David John; Evans, Kathryn Louise

2016-01-01

Bipolar disorder (BD) is a severe, familial psychiatric condition. Progress in understanding the aetiology of BD has been hampered by substantial phenotypic and genetic heterogeneity. We sought to mitigate these confounders by studying a multi-generational family multiply affected by BD and major depressive disorder (MDD), who carry an illness-linked haplotype on chromosome 4p. Within a family, aetiological heterogeneity is likely to be reduced, thus conferring greater power to detect illness-related changes. As accumulating evidence suggests that altered DNA methylation confers risk for BD and MDD, we compared genome-wide methylation between (i) affected carriers of the linked haplotype (ALH) and married-in controls (MIs), (ii) well unaffected haplotype carriers (ULH) and MI, (iii) ALH and ULH and (iv) all haplotype carriers (LH) and MI. Nominally significant differences in DNA methylation were observed in all comparisons, with differences withstanding correction for multiple testing when the ALH or LH group was compared to the MIs. In both comparisons, we observed increased methylation at a locus in FANCI, which was accompanied by increased FANCI expression in the ALH group. FANCI is part of the Fanconi anaemia complementation (FANC) gene family, which are mutated in Fanconi anaemia and participate in DNA repair. Interestingly, several FANC genes have been implicated in psychiatric disorders. Regional analyses of methylation differences identified loci implicated in psychiatric illness by genome-wide association studies, including CACNB2 and the major histocompatibility complex. Gene ontology analysis revealed enrichment for methylation differences in neurologically relevant genes. Our results highlight altered DNA methylation as a potential mechanism by which the linked haplotype might confer risk for mood disorders. Differences in the phenotypic outcome of haplotype carriers might, in part, arise from additional changes in DNA methylation that converge on neurologically important pathways. Further work is required to investigate the underlying mechanisms and functional consequences of the observed differences in methylation.

Alan Bean Art Exhibit

NASA Image and Video Library

2009-07-19

NASA Apollo 7 Astronaut Walt Cunningham, left, and NASA STS-125 Mission Specialist Michael Massimino talk with another guest during the opening of "Alan Bean: Painting Apollo, First Artist on Another World" by NASA Apollo 12 Astronaut and Artist Alan Bean at the National Air and Space Museum, Monday, July 20, 2009 in Washington. The show opening coincided with the 40th anniversary celebration of Apollo. Photo Credit: (NASA/Bill Ingalls)

Synthesis of deuterium-labelled analogues of NLRP3 inflammasome inhibitor MCC950.

PubMed

Salla, Manohar; Butler, Mark S; Massey, Nicholas L; Reid, Janet C; Cooper, Matthew A; Robertson, Avril A B

2018-02-15

This study describes the syntheses of di, tetra and hexa deuterated analogues of the NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome inhibitor MCC950. In di and tetra deuterated analogues, deuteriums were incorporated into the 1,2,3,5,6,7-hexahydro-s-indacene moiety, whereas in the hexa deuterated MCC950 deuteriums were incorporated into the 2-(furan-3-yl)propan-2-ol moiety. The di deuterated MCC950 analogue was synthesised from 4-amino-3,5,6,7-tetrahydro-s-indacen-1(2H)-one 5. Tetra deuterated analogues were synthesised in 10 chemical steps starting with 5-bromo-2,3-dihydro-1H-inden-1-one 9, whereas the hexa deuterated analogue was synthesised in four chemical steps starting with ethyl-3-furoate 24. All of the compounds exhibited similar activity to MCC950 (IC 50  = 8 nM). These deuterated analogues are useful as internal standards in LC-MS analyses of biological samples from in vivo studies. Copyright © 2018 Elsevier Ltd. All rights reserved.

Bacterial mineralization patterns in basaltic aquifers: Implications for possible life in Martian meteorite ALH84001

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

Thomas-Keprta, K.L.; Wentworth, S.J.; Allen, C.C.

To explore the formation and preservation of biogenic features in igneous rocks, the authors have examined the organisms in experimental basaltic microcosms using scanning and transmission electron microscopy. Four types of microorganisms were recognized on the basis of size, morphology, and chemical composition. Some of the organisms mineralized rapidly, whereas others show no evidence of mineralization. Many mineralized cells are hollow and do not contain evidence of microstructure. Filaments, either attached or no longer attached to organisms, are common. Unattached filaments are mineralized and are most likely bacterial appendages (e.g., prosthecae). Features similar in size and morphology to unattached, mineralizedmore » filaments are recognized in martial meteorite ALH84001.« less

Astronaut Alan Bean flies the Astronaut Maneuvering Equipment in the OWS

NASA Image and Video Library

1973-08-28

S73-34207 (28 Aug. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 astronaut Maneuvering Equipment, as seen in this photographic reproduction taken from a television transmission made by a color television camera in the Orbital Workshop (OWS) of the Skylab space station in Earth orbit. Bean is strapped into the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). The M509 exercise was in the forward dome area of the OWS. The dome area is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA

Astronaut Alan L. Bean - Family - Houston, TX

NASA Image and Video Library

1973-07-05

S73-31104 (17 July 1973) --- The wife and children of astronaut Alan L. Bean are photographed at their home near the Johnson Space Center (JSC), where their husband and father is preparing for NASA?s second manned Skylab mission. Bean is commander of the Skylab 3 Earth-orbital mission and will be joined by scientist-astronaut Owen K. Garriott, science pilot, and astronaut Jack R. Lousma, pilot for the schedule two-month mission. With Mrs. Sue Bean are the couple?s children Clay, 17, and Amy Sue, 10; and the family?s pet dog. Photo credit: NASA

Influence of light intensity and spectral composition of artificial light at night on melatonin rhythm and mRNA expression of gonadotropins in roach Rutilus rutilus.

PubMed

Brüning, Anika; Hölker, Franz; Franke, Steffen; Kleiner, Wibke; Kloas, Werner

2018-02-01

In this study we investigated the influence of artificial light at night (ALAN) of different intensities (0, 1, 10, 100 lx) and different colours (blue, green, red) on the daily melatonin rhythm and mRNA expression of gonadotropins in roach Rutilus rutilus, a ubiquitous cyprinid, which occur in standing and moderately flowing freshwater habitats of central Europe. Melatonin concentrations were significantly lowered under nocturnal white light already at 1 lx. Low intensity blue, green and red ALAN lowered the melatonin levels significantly in comparison to a dark control. We conclude that ALAN can disturb melatonin rhythms in roach at very low intensities and at different wavelengths and thus light pollution in urban waters has the potential to impact biological rhythms in fish. However, mRNA expression of gonadotropins was not affected by ALAN during the period of the experiments. Thus, suspected implications of ALAN on reproduction of roach could not be substantiated.

Synthesis, characterisation of polyaniline-Fe3O4 magnetic nanocomposite and its application for removal of an acid violet 19 dye

NASA Astrophysics Data System (ADS)

Patil, Manohar R.; Khairnar, Subhash D.; Shrivastava, V. S.

2016-04-01

The present work deals with the development of a new method for the removal of dyes from an aqueous solution using polyaniline (PANI)-Fe3O4 magnetic nanocomposite. It is synthesised in situ through self-polymerisation of monomer aniline. Photocatalytic degradation studies were carried out for cationic acid violet 19 (acid fuchsine) dye using PANI-Fe3O4 nanocomposite in aqueous solution. Different parameters like catalyst dose, contact time and pH have been studied to optimise reaction condition. The optimum conditions for the removal of the dye are initial concentration 20 mg/l, adsorbent dose 6 gm/l, pH 7. The EDS technique gives elemental composition of synthesised PANI-Fe3O4. The SEM and XRD studies were carried for morphological feature characteristics of PANI-Fe3O4 nanocomposite. The VSM (vibrating sample magnetometer) gives magnetic property of PANI-Fe3O4 nanocomposite; also FT-IR analysis gives characteristics frequency of synthesised PANI-Fe3O4. Besides the above studies kinetic study has also been carried out.

Exposure to dim artificial light at night increases REM sleep and awakenings in humans.

PubMed

Cho, Chul-Hyun; Lee, Heon-Jeong; Yoon, Ho-Kyoung; Kang, Seung-Gul; Bok, Ki-Nam; Jung, Ki-Young; Kim, Leen; Lee, Eun-Il

2016-01-01

Exposure to artificial light at night (ALAN) has become increasing common, especially in developed countries. We investigated the effect of dALAN exposure during sleep in healthy young male subjects. A total of 30 healthy young male volunteers from 21 to 29 years old were recruited for the study. They were randomly divided into two groups depending on light intensity (Group A: 5 lux and Group B: 10 lux). After a quality control process, 23 healthy subjects were included in the study (Group A: 11 subjects, Group B: 12 subjects). Subjects underwent an NPSG session with no light (Night 1) followed by an NPSG session randomly assigned to two different dim light conditions (5 or 10 lux, dom λ: 501.4 nm) for a whole night (Night 2). We found significant sleep structural differences between Nights 1 and 2, but no difference between Groups A and B. Exposure to dALAN during sleep was significantly associated with increased wake time after sleep onset (WASO; F = 7.273, p = 0.014), increased Stage N1 (F = 4.524, p = 0.045), decreased Stage N2 (F = 9.49, p = 0.006), increased Stage R (F = 6.698, p = 0.017) and non-significantly decreased REM density (F = 4.102, p = 0.056). We found that dALAN during sleep affects sleep structure. Exposure to dALAN during sleep increases the frequency of arousals, amount of shallow sleep and amount of REM sleep. This suggests adverse effects of dALAN during sleep on sleep quality and suggests the need to avoid exposure to dALAN during sleep.

The arcuate line hernia: operative treatment and a review of the literature.

PubMed

Montgomery, A; Petersson, U; Austrums, E

2013-06-01

An arcuate line hernia (ALH) is a rare diagnosis with no consensus on how to deal with this condition either when symptomatic or when found accidentally. Suggestions for laparoscopic and open operative techniques are given together with a review of the literature and a presentation of three new cases. The PubMed database was searched for publications on ALH. Identified cases, including three from our department, are reported. Five males and two females, with a median age of 53 years were identified. Three patients were correctly diagnosed on a preoperative CT scan and the rest at surgery. Two patients had bilateral ALHs and four had other concomitant hernias repaired. Small bowel was present in the hernia in three cases and sigmoid colon in one. In one case, an emergency operation was performed due to bowel incarceration. Five patients had laparoscopic repairs, three with mesh and two without. Two patients, one converted from laparoscopic to open operation, had open mesh repairs. The postoperative course was uneventful in all cases, and no recurrences have been reported at a median follow-up of 6 months. A laparoscopic approach is recommended for diagnostic purposes, for pre-peritoneal mesh placement and for repair of concomitant hernias in both elective and emergency settings. Highlighting its existence might help general surgeons in interpreting an unusual finding on a CT scan or at operation.

Synthesis, Characterisation, and Evaluation of a Cross-Linked Disulphide Amide-Anhydride-Containing Polymer Based on Cysteine for Colonic Drug Delivery

PubMed Central

Lim, Vuanghao; Peh, Kok Khiang; Sahudin, Shariza

2013-01-01

The use of disulphide polymers, a low redox potential responsive delivery, is one strategy for targeting drugs to the colon so that they are specifically released there. The objective of this study was to synthesise a new cross-linked disulphide-containing polymer based on the amino acid cysteine as a colon drug delivery system and to evaluate the efficiency of the polymers for colon targeted drug delivery under the condition of a low redox potential. The disulphide cross-linked polymers were synthesised via air oxidation of 1,2-ethanedithiol and 3-mercapto-N-2-(3-mercaptopropionamide)-3-mercapto propionic anhydride (trithiol monomers) using different ratio combinations. Four types of polymers were synthesised: P10, P11, P151, and P15. All compounds synthesised were characterised by NMR, IR, LC-MS, CHNS analysis, Raman spectrometry, SEM-EDX, and elemental mapping. The synthesised polymers were evaluated in chemical reduction studies that were performed in zinc/acetic acid solution. The suitability of each polymer for use in colon-targeted drug delivery was investigated in vitro using simulated conditions. Chemical reduction studies showed that all polymers were reduced after 0.5–1.0 h, but different polymers had different thiol concentrations. The bacterial degradation studies showed that the polymers were biodegraded in the anaerobic colonic bacterial medium. Degradation was most pronounced for polymer P15. This result complements the general consensus that biodegradability depends on the swellability of polymers in an aqueous environment. Overall, these results suggest that the cross-linked disulphide-containing polymers described herein could be used as coatings for drugs delivered to the colon. PMID:24351841

Apollo 12 Mission image - Astronaut Alan L. Bean,lunar module pilot,and two U.S. spacecraft

NASA Image and Video Library

1969-11-20

AS12-48-7134 (20 Nov. 1969) --- This unusual photograph, taken during the second Apollo 12 extravehicular activity (EVA), shows two U.S. spacecraft on the surface of the moon. The Apollo 12 Lunar Module (LM) is in the background. The unmanned Surveyor 3 spacecraft is in the foreground. The Apollo 12 LM, with astronauts Charles Conrad Jr. and Alan L. Bean aboard, landed about 600 feet from Surveyor 3 in the Ocean of Storms. The television camera and several other pieces were taken from Surveyor 3 and brought back to Earth for scientific examination. Here, Conrad examines the Surveyor's TV camera prior to detaching it. Astronaut Richard F. Gordon Jr. remained with the Apollo 12 Command and Service Modules (CSM) in lunar orbit while Conrad and Bean descended in the LM to explore the moon. Surveyor 3 soft-landed on the moon on April 19, 1967.

Professor Alan Turner (1947-2012). Specialist in Miocene-Pleistocene Carnivora, particularly Felidae and Hyaenidae and their palaeoecology

NASA Astrophysics Data System (ADS)

O'Regan, Hannah; Turner, Adam; Antón, Mauricio

2014-07-01

Alan first trained as a telecom engineer, working for the GPO (General Post Office) which later became British Telecom. He never forgot this early training and was fascinated by how things worked - always happy to take something apart and fix it (although his attempt to close a large plate glass window with a geological hammer was not one of his successes). Following a few years as an engineer, he went to Sheffield University to study archaeology as a mature student in 1973. At this time Sheffield was a hotbed of prehistory with Graeme Barker, Robin Dennell and many others contributing to a truly research-led degree (with tutorials in the pub (well, it was the 1970s)) (Fig. 1). Alan's interest in bones developed at this time, and having graduated in 1976 he went on to take a PhD, supervised by Robin Dennell, on "Aspects of the palaeoecology of large predators, including man, during the British Upper Pleistocene, with particular emphasis on predator-prey relationships" which resulted in a life-long interest in the Carnivora and particularly hyaenas. Following his PhD, Alan moved to the Environmental Archaeology Unit at York to undertake a Science Research Council project on the morphometrics of domestic cattle and pigs from Coppergate and other major urban excavations in the city. Faced with a lot of measurements and statistics, Alan retained his interest in the animals themselves. The project also confirmed to Alan that prehistory was his metier, rather than the historic periods. Former York colleagues still fondly recall Alan's dry wit, and the day that he successfully put the irritating lab telephone beyond use with no externally visible trace of damage.

Artificial light at night affects sleep behaviour differently in two closely related songbird species.

PubMed

Sun, Jiachen; Raap, Thomas; Pinxten, Rianne; Eens, Marcel

2017-12-01

Artificial light at night (ALAN) or light pollution is an increasing and worldwide problem. There is growing concern that because of the disruption of natural light cycles, ALAN may pose serious risks for wildlife. While ALAN has been shown to affect many aspects of animal behaviour and physiology, few studies have experimentally studied whether individuals of different species in the wild respond differently to ALAN. Here, we investigated the effect of ALAN on sleep behaviour in two closely related songbird species inhabiting the same study area and roosting/breeding in similar nest boxes. We experimentally exposed free-living great tits (Parus major) and blue tits (Cyanistes caeruleus) to artificial light inside their nest boxes and observed changes in their sleep behaviour compared to the previous night when the nest boxes were dark. In line with previous studies, sleep behaviour of both species did not differ under dark conditions. ALAN disrupted sleep in both great and blue tits. However, compared to blue tits, great tits showed more pronounced effects and more aspects of sleep were affected. Light exposed great tits entered the nest boxes and fell asleep later, woke up and exited the nest boxes earlier, and the total sleep amount and sleep percentage were reduced. By contrast, these changes in sleep behaviour were not found in light exposed blue tits. Our field experiment, using exactly the same light manipulation in both species, provides direct evidence that two closely related species respond differently to ALAN, while their sleep behaviour under dark conditions was similar. Our research suggests that findings for one species cannot necessarily be generalised to other species, even closely-related species. Furthermore, species-specific effects could have implications for community dynamics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exposure Histories of Calcalong Creek and LEW 88516 Meteorites

NASA Astrophysics Data System (ADS)

Nishiizumi, K.; Arnold, J. R.; Caffee, M. W.; Finkel, R. C.; Southon, J.

1992-07-01

We report here preliminary results of cosmogenic radionuclides in lunar meteorite Calcalong Creek and shergottite LEW 88516 for study of exposure histories. Table 1 shows ^36Cl and ^10Be results for these two meteorites along with previous measurements of ^36Cl and ^10Be of SNC meteorites. The AMS measurements were performed at LLNL. Measured ^36Cl activities, in dpm/kg meteorite, were normalized to the target element concentration, dpm/kg (8Ca+Fe), for comparison and shown in the table. The ^36Cl saturation activity is ~22 +- 2 dpm/kg (8Ca+Fe) for 4-pi irradiation. Calcalong Creek: This is the first lunar meteorite found outside Antarctica (Hill et al., 1991; Marvin and Holmberg, 1992). ^36Cl and ^10Be activity levels are slightly (10-20%) higher than the production rate of these nuclides on the moon. One possibility is that the meteorite was ejected from near the surface (<70 g/cm^2) of the moon and transferred to the earth. The transition time from moon to earth was ~0.2 My. The other simple case is that the meteorite was ejected from deep (at least a few meters) in the moon, like Yamato 82192, and exposed to cosmic rays as a small body. The transition time in this case was ~2 My. The terrestrial age must be <70 ky for either case. Other cosmogenic nuclide measurements (in progress) are required to constrain the history further. LEW 88516: This meteorite was classified as a shergottite (Mason, 1991). The recovered mass is 13.2 g. We measured ^36Cl and ^10Be in 93.9 mg of homogenized bulk sample. All aspects of petrography and bulk chemical composition of LEW 88516 are remarkably similar to those of ALH 77005 (Boynton et al., 1992; Lindstrom et al., 1992). Since the ^10Be activities of ALH 77005 samples vary from 13.7 to 16.2 dpm/kg with increasing shielding depth (Nishiizumi et al., 1986a), the average of ^10Be in ALH 77005 is slightly lower than ^10Be in LEW 88516. The calculated ^10Be exposure age is ~3.0 My. The normalized ^36Cl activity of LEW 88516 is near saturation for a small object (no significant thermal neutron effect). On this assumption, the terrestrial age of the meteorite is shorter than 50 ky. The ^36Cl terrestrial age of ALH 77005 is ~0.2 My and in good agreement with the ^81Kr terrestrial age of (0.19 +- 0.07) My (Schultz and Freundel, 1986). LEW 88516 and ALH 77005 are separate falls. Probably, however, these two meteorites and Shergotty were ejected in the same event on the parent body, since they have same exposure age within error. Table 1, which in the hard copy appears here, shows the concentration of ^36Cl and ^10Be. References: Boynton W. V. et al. (1992) Lunar Planet. Sci. XXIII, 147-148. Hill D. H. et al. (1991) Nature 352, 614-617. Lindstrom M. M. et al. (1992) Lunar Planet. Sci. XXIII, 783-784. Marvin U. B. and Holmberg B. B. (1992) Lunar Planet. Sci. XXIII, 849- 850. Mason B. (1991) Antarctic Meteorite Newsletter 14 (2), 19. Nishiizumi K. et al. (1986a) Meteoritics 21, 472-473. Nishiizumi K. et al. (1986b) Geochim. Cosmochim. Acta 50, 1017- 1021. Pal D. K. et al. (1986) Geochim. Cosmochim. Acta 50, 2405-2409. Schultz L. and Freundel M. (1984) Meteoritics 19, 310.

Search for Past Life on Mars: Possible Relict Biogenic Activity in Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

McKay, David S.; Gibson, Everett K., Jr.; Thomas-Keprta, Kathie L.; Vali, Hojatollah; Romanek, Christopher S.; Clemett, Simon J.; Chillier, Xavier D. F.; Maechling, Claude R.; Zare, Richard N.

1996-01-01

Fresh fracture surfaces of the martian meteorite ALH84001 contain abundant polycyclic aromatic hydrocarbons (PAHs). These fresh fracture surfaces also display carbonate globules. Contamination studies suggest the PAHs are indigenous to the meteorite. High resolution scanning and transmission electron microscopy study of surface textures and internal structures of selected carbonate globules show that the globules contain fine-grained, secondary phases of single-domain magnetite and Fe-monosulfides. The carbonate globules are similar in texture and size to some terrestrial bacterially induced carbonate precipitates. Although inorganic formation is possible, formation of the globules by biogenic processes could explain many of the observed features including the PAHs. The PAHs, the carbonate globules, and their associated secondary mineral phases and textures could thus be fossil remains of a past martian biota.

Influence of artificially induced light pollution on the hormone system of two common fish species, perch and roach, in a rural habitat

PubMed Central

Brüning, Anika; Kloas, Werner; Preuer, Torsten; Hölker, Franz

2018-01-01

Abstract Almost all life on earth has adapted to natural cycles of light and dark by evolving circadian and circannual rhythms to synchronize behavioural and physiological processes with the environment. Artificial light at night (ALAN) is suspected to interfere with these rhythms. In this study we examined the influence of ALAN on nocturnal melatonin and sex steroid blood concentrations and mRNA expression of gonadotropins in the pituitary of European perch (Perca fluviatilis) and roach (Rutilus rutilus). In a rural experimental setting, fish were held in net cages in drainage channels experiencing either additional ALAN of ~15 lx at the water surface or natural light conditions at half-moon. No differences in melatonin concentrations between ALAN and natural conditions were detected. However, blood concentration of sex steroids (17β-estradiol; 11-ketotestosterone) as well as mRNA expression of gonadotropins (luteinizing hormone, follicle stimulating hormone) was reduced in both fish species. We conclude that ALAN can disturb biological rhythms in fish in urban waters. However, impacts on melatonin rhythm might have been blurred by individual differences, sampling methods and moonlight. The effect of ALAN on biomarkers of reproduction suggests a photo-labile period around the onset of gonadogenesis, including the experimental period (August). Light pollution therefore has a great potential to influence crucial life history traits with unpredictable outcome for fish population dynamics. PMID:29686874

Artificial light at night causes an unexpected increase in oxalate in developing male songbirds

PubMed Central

Pinxten, Rianne; Eens, Marcel

2018-01-01

Abstract Artificial light at night (ALAN) is a widespread and increasing environmental pollutant with known negative impacts on animal physiology and development. Physiological effects could occur through sleep disruption and deprivation, but this is difficult to quantify, especially in small developing birds. Sleep loss can potentially be quantified by using oxalate, a biomarker for sleep debt in adult humans and rats. We examined the effect of ALAN on oxalate in free-living developing great tits (Parus major) as effects during early-life could have long-lasting and irreversible consequences. Nestlings’ physiology was quantified at baseline (= 13 days after hatching) and again after two nights of continued darkness (control) or exposure to ALAN (treatment). We found that ALAN increased oxalate levels but only in male nestlings, rather than decreasing it as was found in sleep-deprived humans and rats. Our results using developing birds differ strongly from those obtained with adult mammals. However, we used ALAN to reduce sleep while in rats forced movement was used. Finally, we used free-living opposed to laboratory animals. Whether oxalate is a reliable marker of sleep loss in developing great tits remains to be examined. Potentially the increase of oxalate in male nestlings was unrelated to sleep debt. Nonetheless, our results substantiate physiological effects of ALAN in developing animals and may provide a foundation for future work with free-living animals. PMID:29479432

Influence of artificially induced light pollution on the hormone system of two common fish species, perch and roach, in a rural habitat.

PubMed

Brüning, Anika; Kloas, Werner; Preuer, Torsten; Hölker, Franz

2018-01-01

Almost all life on earth has adapted to natural cycles of light and dark by evolving circadian and circannual rhythms to synchronize behavioural and physiological processes with the environment. Artificial light at night (ALAN) is suspected to interfere with these rhythms. In this study we examined the influence of ALAN on nocturnal melatonin and sex steroid blood concentrations and mRNA expression of gonadotropins in the pituitary of European perch ( Perca fluviatilis ) and roach ( Rutilus rutilus ). In a rural experimental setting, fish were held in net cages in drainage channels experiencing either additional ALAN of ~15 lx at the water surface or natural light conditions at half-moon. No differences in melatonin concentrations between ALAN and natural conditions were detected. However, blood concentration of sex steroids (17β-estradiol; 11-ketotestosterone) as well as mRNA expression of gonadotropins (luteinizing hormone, follicle stimulating hormone) was reduced in both fish species. We conclude that ALAN can disturb biological rhythms in fish in urban waters. However, impacts on melatonin rhythm might have been blurred by individual differences, sampling methods and moonlight. The effect of ALAN on biomarkers of reproduction suggests a photo-labile period around the onset of gonadogenesis, including the experimental period (August). Light pollution therefore has a great potential to influence crucial life history traits with unpredictable outcome for fish population dynamics.

Solvent-free synthesis, spectral correlations and antimicrobial activities of some aryl E 2-propen-1-ones

NASA Astrophysics Data System (ADS)

Sathiyamoorthi, K.; Mala, V.; Sakthinathan, S. P.; Kamalakkannan, D.; Suresh, R.; Vanangamudi, G.; Thirunarayanan, G.

2013-08-01

Totally 38 aryl E 2-propen-1-ones including nine substituted styryl 4-iodophenyl ketones have been synthesised using solvent-free SiO2-H3PO4 catalyzed Aldol condensation between respective methyl ketones and substituted benzaldehydes under microwave irradiation. The yields of the ketones are more than 80%. The synthesised chalcones were characterized by their analytical, physical and spectroscopic data. The spectral frequencies of synthesised substituted styryl 4-iodophenyl ketones have been correlated with Hammett substituent constants, F and R parameters using single and multi-linear regression analysis. The antimicrobial activities of 4-iodophenyl chalcones have been studied using Bauer-Kirby method.

Once a physicist: Alan Pierson

NASA Astrophysics Data System (ADS)

2016-08-01

Alan Pierson is artistic director and conductor of the New York-based contemporary-music ensemble Alarm Will Sound, and a professor of conducting at Northwestern University's Bienen School of Music in Illinois

Water-Solubilized, Cap-Stabilized, Helical Polyalanines: Calibration Standards for NMR and CD Analyses

PubMed Central

Heitmann, Björn; Job, Gabriel E.; Kennedy, Robert J.; Walker, Sharon M.; Kemp, Daniel S.

2006-01-01

NMR and CD studies are reported for two length series of solubilized, spaced, highly helical polyalanines that are N-capped by the optimal helix stabilizer βAsp-Hel and C-capped by β-aminoalanine beta and that are studied in water at 2 °C, pH 1–8. NMR analysis yields a structural characterization of the peptide AcβAspHelAla8betaNH2 and selected members of one βAspHelAlanbeta series. At pH > 4.5 the βAspHel cap provides a preorganized triad of carboxylate anion and two amide residues that is complementary to the helical polyalanine N-terminus. The C-terminal β-aminoalanine assumes a helix-stabilizing conformation consistent with literature precedents. H(N)CO NMR experiments applied to capped, uniformly 13C- and 15N-labeled Ala8 and Ala12 peptides define Alan hydrogen bonding signatures as α-helical without detectable 310 character. Relative NH→ND exchange rates yield site protection factors PFi that define uniquely high fractional helicities FH for the peptide Alan regions. These Alan calibration series, studied in water and lacking helix-stabilizing tertiary structure, yield the first 13C NMR chemical shifts, 3JHNHα coupling constants, and CD ellipticities [θMolar]λ,n characteristic of a fully helical alanine within an Alan context. CD data are used to assign parameters X and [θ]λ,∞, required for rigorous calculation of FH values from CD ellipticities. PMID:15701003

Multispectroscopic (FTIR, XPS, and TOFMS-TPD) Investigation of the Core-Shell Bonding in Sonochemically Prepared Aluminum Nanoparticles Capped with Oleic Acid (Postprint)

DTIC Science & Technology

2010-03-04

Alane N,N-dimethylethylamine in a 0.4 M toluene solution, titanium (IV) isopropoxide (98%), oleic acid (99%), dodecane (99% and anhydrous), and oleyl...inside a dry nitrogen glovebox, where alane N,N-dimethylethylamine and a titanium (IV) isopropoxide catalyst were added to the solution. The...concentrations of the alane complex and titanium catalyst in this solution were 50 and 0.55 mM, respectively. This solution was then transferred into a sonication

2011 Joint Program Executive Office for Chemical and Biological Defense Advance Planning Briefing for Industry (APBI) Held in Baltimore, Maryland on September 7-9, 2011

DTIC Science & Technology

2011-09-09

Chemical and Biological Defense Defense Threat Reduction Agency (DTRA)/Joint Science & Technology Office (JSTO) Dr. Alan Rudolph , Director, Chemical...Mr. Douglas W. Bryce 9:05 am – 9:45 am Dr. Alan Rudolph Director, Chemical and Biological Technologies Directorate, Defense Threat Reduction...Joint Science and Technology Office for Chemical and Biological Defense Dr. Alan S. Rudolph Mr. David K. Grimm Acting Heidi Shyu Joint Combat

Surgical excision of pure flat epithelial atypia identified on core needle breast biopsy.

PubMed

Prowler, Vanessa L; Joh, Jennifer E; Acs, Geza; Kiluk, John V; Laronga, Christine; Khakpour, Nazanin; Lee, M Catherine

2014-08-01

The biology of flat epithelial atypia (FEA) is still being investigated as its presence becomes more frequent on biopsy specimens. FEA is more commonly associated with malignancy when found in association with ADH, ALH or LCIS. Pure FEA is only upgraded to cancer in 3.2% of patients. Surgical excision of pure FEA found on core needle biopsy results in overtreatment in the vast majority of breast patients and may not be necessary. Copyright © 2014 Elsevier Ltd. All rights reserved.

Self-Defense by Any Other Name is Still Self-Defense

DTIC Science & Technology

2003-04-01

Unlimited D D15Th3WON STAT13ENT L YNANNOUNIPV 03 JUSMIICATION BY DISTIBUTON/T AVAILABILIT CODES DIST1ZDtmN AVAILABILI AQM SPECI~ALH DATE ACCMSIONED...homeport? When the invasion force enters another state’s sovereign waters ? Is it as simplistic as which side fired the first shot? 34 These rhetorical...States’ sovereignty in her territorial waters and even led to the occasional killing of Whereas armed vessels sailing under authority or pretence of

Re{sup 3+} : YAG laser ceramics: synthesis, optical properties and laser characteristics

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

Bagayev, S N; Vatnik, S M; Vedin, I A

2015-05-31

Highly transparent yttrium aluminium garnet ceramics doped with holmium or ytterbium or neodymium are synthesised. The ceramics were made of a mixture of nanopowders synthesised by laser ablation. The structural and spectral characteristics of ceramics are studied. In the samples with holmium Ho{sup 3+} and neodymium Nd{sup 3+} ions, lasing was achieved with a slope efficiency of 40% and 35.3%, respectively; the maximum laser power exceeded 4 W. The internal absorption and scattering losses for 1% Nd : YAG ceramics are estimated to be 1.6 × 10{sup -2} cm{sup -1}. (extreme light fields and their applications)

Anti-acne, anti-dandruff and anti-breast cancer efficacy of green synthesised silver nanoparticles using Coriandrum sativum leaf extract.

PubMed

Sathishkumar, Palanivel; Preethi, Johnson; Vijayan, Raji; Mohd Yusoff, Abdull Rahim; Ameen, Fuad; Suresh, Sadhasivam; Balagurunathan, Ramasamy; Palvannan, Thayumanavan

2016-10-01

In this present investigation, AgNPs were green synthesised using Coriandrum sativum leaf extract. The physicochemical properties of AgNPs were characterised using UV-visible spectrophotometer, field emission scanning microscopy/energy dispersive X-ray (FESEM/EDX), Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analysis. Further, in vitro anti-acne, anti-dandruff and anti-breast cancer efficacy of green synthesised AgNPs were assessed against Propionibacterium acnes MTCC 1951, Malassezia furfur MTCC 1374 and human breast adenocarcinoma (MCF-7) cell line, respectively. The flavonoids present in the plant extract were responsible for the AgNPs synthesis. The green synthesised nanoparticles size was found to be ≈37nm. The BET analysis result shows that the surface area of the synthesised AgNPs was found to be 33.72m(2)g(-1). The minimal inhibitory concentration (MIC) of AgNPs for acne causative agent P. acnes and dandruff causative agent M. furfur was found to be at 3.1 and 25μgmL(-1), respectively. The half maximal inhibitory concentration (IC50) value of the AgNPs for MCF-7 cells was calculated as 30.5μgmL(-1) and complete inhibition was observed at a concentration of 100μgmL(-1). Finally, our results proved that green synthesised AgNPs using C. sativum have great potential in biomedical applications such as anti-acne, anti-dandruff and anti-breast cancer treatment. Copyright © 2016. Published by Elsevier B.V.

Cumberland Falls chondritic inclusions. III - Consortium study of relationship to inclusions in Allan Hills 78113 aubrite

NASA Astrophysics Data System (ADS)

Lipschutz, Michael E.; Verkouteren, R. Michael; Sears, Derek W. G.; Hasan, Fouad A.; Prinz, Martin.; Weisberg, M. K.; Nehru, Cherukupalli E.; Delaney, Jeremy S.; Grossman, Lawrence; Boily, Michel

1988-07-01

The contents of Ag, Au, Bi, Cd, Co, Cs, Ga, In, Rb, Sb, Se, Te, Tl, U, and Zn in large chondritic clasts from the Cumbersand Falls aubrite were determined by radiochemical neutron activation analysis, and the results, together with the results of a mineralogical investigation, were compared with respective data obtained for three primitive inclusions from the ALH A78113 aubrite. The results indicated that the clasts from both aubrite sources constitute a single chondritic suite. The analyses data, together with the results of thermoluminescence data for Cumberland Falls chondritic inclusions and achondritic host, indicate that inclusions in Cumberland Falls and in ALH A78113 aubrite represent a primitive chondrite sample suite whose properties were established during primary nebular accretion and condensation over a broad redox range.

Long-term dim light during nighttime changes activity patterns and space use in experimental small mammal populations.

PubMed

Hoffmann, Julia; Palme, Rupert; Eccard, Jana Anja

2018-07-01

Artificial light at night (ALAN) is spreading worldwide and thereby is increasingly interfering with natural dark-light cycles. Meanwhile, effects of very low intensities of light pollution on animals have rarely been investigated. We explored the effects of low intensity ALAN over seven months in eight experimental bank vole (Myodes glareolus) populations in large grassland enclosures over winter and early breeding season, using LED garden lamps. Initial populations consisted of eight individuals (32 animals per hectare) in enclosures with or without ALAN. We found that bank voles under ALAN experienced changes in daily activity patterns and space use behavior, measured by automated radiotelemetry. There were no differences in survival and body mass, measured with live trapping, and none in levels of fecal glucocorticoid metabolites. Voles in the ALAN treatment showed higher activity at night during half moon, and had larger day ranges during new moon. Thus, even low levels of light pollution as experienced in remote areas or by sky glow can lead to changes in animal behavior and could have consequences for species interactions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Portrait of Astronaut Alan L. Bean

NASA Technical Reports Server (NTRS)

1969-01-01

Portrait of Astronaut Alan L. Bean, Prime Crew Lunar Module Pilot of the Apollo 12 Lunar Landing Mission, in his space suit minus the helmet. He is standing outside beside a mock-up of the Lunar Lander.

Astronaut Alan Shepard - U.S.S. Champlain - Post-Recovery Mercury Capsule

NASA Image and Video Library

1961-05-05

S61-02727 (5 May 1961) --- Astronaut Alan B. Shepard is seen on the deck of the USS Lake Champlain after the recovery of his Mercury capsule in the western Atlantic Ocean. Shepard and the Mercury spacecraft designated the ?Freedom 7? were flown to the deck of the recovery ship within 11 minutes of splashdown. MR-3 was the United States? first manned space mission. The spacecraft attained a maximum speed of 5,180 miles per hour, reached an altitude of 116 1/2 statute miles, and landed 302 statute miles downrange from Cape Canaveral, Florida. The suborbital mission lasted 15 minutes and 22 seconds. Photo credit: NASA or National Aeronautics and Space Administration

Division F Commission 53: Extrasolar Planets

NASA Astrophysics Data System (ADS)

Lecavelier Des Etangs, Alain; Minniti, Dante; Boss, Alan; Mayor, Michel; Bodenheimer, Peter; Collier-Cameron, Andrew; Jayawardhana, Ray; Kokubo, Eiichiro; Mardling, Rosemary; Queloz, Didier; Rauer, Heike; Zhao, Gang

2016-04-01

The IAU Working Group on Extrasolar Planets (WGESP) was created by the Executive Council as a Working Group of Division III. This decision took place in June 1999, that is only 7 years after the discovery of planets around the pulsar PSR B1257+12 and 4 years after the discovery of 51 Peg b. This working group was renewed for 3 years at the General Assembly in 2003 in Sydney, Australia. It was chaired by Alan Boss from Carnegie Institution of Washington. The WGESP members were Paul Butler, William Hubbard, Philip Ianna, Martin Kürster, Jack Lissauer, Michel Mayor, Karen Meech, Francois Mignard, Alan Penny, Andreas Quirrenbach, Jill Tarter, and Alfred Vidal-Madjar.

Impact of the Geoplasma on a Spaceborne GPS(Global Positioning System) Receiver System - A Preliminary Study

DTIC Science & Technology

1989-02-28

valug vhich *dvrivv the A044 1 hý’we not met with mucth suktflV. Klobutchsr Ot al (1987) have obtained ThC data for tho first ti=# "t a polar cap sit...ntudy in 1984. found teei s vaiblty int TE. as-pri trainsg of ehnmntof the -ardor of J-O1gtffs~ fltpt riqd4 al ghlort a; tpný mrl’seO Were nbtrvud... ALE ) THEN ENC - V3 * ZEC ELSE EAR - (SIN (P1(3) - ALH) * 2.92) **6 F3 - EXP (- EAR) "V3 - V3 * F3 F3 - 1.0 - F3C* C* S3 - SOLAR CYCLE FUNCTION IF(1.1

Astronaut Alan Bean participates in lunar surface simulation

NASA Technical Reports Server (NTRS)

1969-01-01

Astronaut Alan L. Bean, lunar module pilot of the Apollo 12 lunar landing mission, participates in lunar surface simulation training in bldg 29 at the Manned Spacecraft Center. Bean is strapped to a one-sixth gravity simulator.

78 FR 31627 - Thirteenth Meeting: RTCA Special Committee 222, Inmarsat AMS(R)S.

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-24

... Conference. Participants who will be traveling to the meeting should contact Alan Schuster-Bruce, alan... open to the interested public but limited to space availability. With the approval of the chairman...

Modeling Continuous-Time Random Processes in Digital Computer Simulations of Physical Systems

DTIC Science & Technology

1986-08-27

hf) + BD1QD1B31 + BD2QD2B62 + BD3QD3BZ3 + BD4QD4BZ4 (51) where ODk = E[NDk-_•k] for k = 1 to 4. Note that PD(ti+l) has four BDiQDiBZi terms, one from...3 , collecting terms, and rearrang- ing equation (95), results in (aUz 3 + a 2 z 2 + a3z + ag4)hBV(z)Xlz) , (96) z 4 - alhAz 3 - (1 + a2 hA)z 2 - a 3...approximate the Taylor series form of I(h,I)? To answer this question, expand equation (1ll) in a series form , collect terms and compare it to 1(hI) . EhA

Early life exposure to artificial light at night affects the physiological condition: An experimental study on the ecophysiology of free-living nestling songbirds.

PubMed

Raap, Thomas; Casasole, Giulia; Pinxten, Rianne; Eens, Marcel

2016-11-01

Light pollution or artificial light at night (ALAN) is increasingly recognised to be an important anthropogenic environmental pressure on wildlife, affecting animal behaviour and physiology. Early life experiences are extremely important for the development, physiological status and health of organisms, and as such, early exposure to artificial light may have detrimental consequences for organism fitness. We experimentally manipulated the light environment of free-living great tit nestlings (Parus major), an important model species in evolutionary and environmental research. Haptoglobin (Hp) and nitric oxide (NOx), as important indicators of immunity, health, and physiological condition, were quantified in nestlings at baseline (13 days after hatching) and after a two night exposure to ALAN. We found that ALAN increased Hp and decreased NOx. ALAN may increase stress and oxidative stress and reduce melatonin which could subsequently lead to increased Hp and decreased NOx. Haptoglobin is part of the immune response and mounting an immune response is costly in energy and resources and, trade-offs are likely to occur with other energetically demanding tasks, such as survival or reproduction. Acute inhibition of NOx may have a cascading effect as it also affects other physiological aspects and may negatively affect immunocompetence. The consequences of the observed effects on Hp and NOx remain to be examined. Our study provides experimental field evidence that ALAN affects nestlings' physiology during development and early life exposure to ALAN could therefore have long lasting effects throughout adulthood. Copyright © 2016 Elsevier Ltd. All rights reserved.

Apollo 12 Mission image - Astronaut Alan L. Bean,lunar module pilot,and two U.S. spacecraft

NASA Image and Video Library

1969-11-20

AS12-48-7136 (20 Nov. 1969) --- Astronaut Charles Conrad Jr., commander, examines the unmanned Surveyor 3 spacecraft during the second Apollo 12 extravehicular activity (EVA). In the background is the lunar module, parked where the crew had landed it in the Ocean of Storms only 600 feet from Surveyor 3. This series of pictures documents the only occasion wherein Apollo astronauts landed near or had hands-on contact with another spacecraft which had arrived on the moon's surface well ahead of them. This picture was taken by astronaut Alan L. Bean, lunar module pilot. The television camera and several other pieces were taken from Surveyor 3 and brought back to Earth for scientific examination. Surveyor 3 soft-landed on the moon on April 19, 1967. Astronaut Richard F. Gordon Jr., command module pilot, remained with the Command and Service Modules (CSM) in lunar orbit while astronauts Conrad and Bean descended in the LM to explore the moon. Photo credit: NASA

Green Synthesis of Iron Nanoparticles and Their Environmental Applications and Implications

PubMed Central

Saif, Sadia; Tahir, Arifa; Chen, Yongsheng

2016-01-01

Recent advances in nanoscience and nanotechnology have also led to the development of novel nanomaterials, which ultimately increase potential health and environmental hazards. Interest in developing environmentally benign procedures for the synthesis of metallic nanoparticles has been increased. The purpose is to minimize the negative impacts of synthetic procedures, their accompanying chemicals and derivative compounds. The exploitation of different biomaterials for the synthesis of nanoparticles is considered a valuable approach in green nanotechnology. Biological resources such as bacteria, algae fungi and plants have been used for the production of low-cost, energy-efficient, and nontoxic environmental friendly metallic nanoparticles. This review provides an overview of various reports of green synthesised zero valent metallic iron (ZVMI) and iron oxide (Fe2O3/Fe3O4) nanoparticles (NPs) and highlights their substantial applications in environmental pollution control. This review also summarizes the ecotoxicological impacts of green synthesised iron nanoparticles opposed to non-green synthesised iron nanoparticles. PMID:28335338

Hydrogeological Interpretation of Candidate Origin Sites for Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

Gulick, Virginia C.; McKay, Chris; Cuzzi, Jeffrey N. (Technical Monitor)

1996-01-01

Barlow (this meeting) has identified two potential source craters for the martian meteorite ALH84001. The craters are at 11.7 deg S, 243.3 deg W (Mare Tyrrhenum site) and 14.0 deg S, 343.5 deg W (Sinus Sabaeus site). As noted by Barlow, both craters lie in the heavily cratered terrain (HCT) and are adjacent to fluvial valleys, Here I explore the fluvial history of these areas based upon the surrounding valley morphology. The most prominent valley network at the Sabaeus site is Evros Vallis. This wide, flat-floored valley is approximately 600 km long with an average width of 2.5 km and a depth of 220 m. The eroded volume of the entire Evros network is approximately 6 x 10(exp 11) cc. This is typical for networks located in the heavily cratered terrain (e.g. Warrego and Parana Valles). Evros is also an isolated valley system. No similar networks are found in the surrounding terrain. Thus it is unlikely that Evros formed as a result of widespread rainfall. A localized water source, such as discharge of a hydrothermal system or localized melting of snowfall, seems more consistent Previous modeling has demonstrated that only hydrothermal systems associated with high permeability subsurfaces can discharge sufficient water to form a valley network. The bulk of the discharge from such systems is consequently low temperature, slightly heated water Precipitation of calcium carbonate by low temperature fluids is consistent with most interpretations of the geochemistry of ALH84001. Available imagery at the Tyrrhenum site is of lesser quality. While eroded units of the HCT are nearby, there are no comparable well developed valley networks at this site. Erosion is instead manifested predominantly as gullies on slopes. This style of erosion suggests that water was not present at this site for the length of time as at the more integrated Sabaeus site. The superposition of fluidized ejecta blankets suggests however that ground water or ground ice was still present at this locality fairly recently, if the chosen crater is indeed correct.

Human Resource Automation Architecture Validation for a Transforming Army

DTIC Science & Technology

2005-03-03

2004. 26 Ibid 27 Alan Bundy, “One Essential Direction: Information Literacy , Information Technology Fluency” 30 May 2003. available from...smartcard.html>. Internet. Accessed 11 December 2004. Bundy, Alan “One Essential Direction: Information Literacy , Information Technology Fluency” 30

MERCURY-ATLAS (MA)-9 - SHEPARD, ALAN B., JR. ASTRONAUT - MERCURY CONTROL CENTER (MCC) - CAPE

NASA Image and Video Library

1963-05-16

S63-07857 (15-16 May 1963) --- Astronaut Alan Shepard (left) and Walter C. Williams monitor progress of the Mercury Atlas 9 (MA-9) mission from Mercury Control Center, Cape Canaveral, Florida. Photo credit: NASA

Astronaut Alan Bean works on Modular Equipment Stowage Assembly

NASA Technical Reports Server (NTRS)

1969-01-01

Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 lunar landing mission, works at the Modular Equipment Stowage Assembly (MESA) on the Apollo 12 Lunar Module during the mission's first extravehicular activity, EVA-1, on November 19, 1969.

Breast Changes and Conditions

Cancer.gov

Breast changes include benign conditions and those that increase the risk of breast cancer. Symptoms and treatment of breast conditions such as ADH, ALH, cysts, DCIS, and LCIS are explained to women who may have received an abnormal mammogram finding.

Remote identification of research and educational activities using spectral properties of nighttime light

NASA Astrophysics Data System (ADS)

Rybnikova, Nataliya A.; Portnov, Boris A.

2017-06-01

Research and educational activities (R&EAs) are major forces behind modern economic growth. However, data on geographic location of such activities are often poorly reported. According to our research hypothesis, intensities and spectral properties of artificial light-at-night (ALAN) can be used for remote identification of R&EAs, due to their unique ALAN signatures. In order to develop activity identification models, we carried out a series of in situ measurements of ALAN intensities and spectral properties in a major metropolitan area in Israel. For this task, we used an illuminance CL-500A spectrophotometer that measures the total intensity and spectral irradiance of ALAN, incremented by a 1-nm pitch, from 360 to 780 nm. As our analysis shows, logistic regressions, incorporating ALAN intensities at the peak or near-peak wavelengths, and geographical attributes of the measurement sites as controls, succeeded to predict correctly up to 98.6% of the actual locations of R&EAs. A digital camera satellite image, obtained from the Astronaut Photography Database, was used for the model's validation. According to the validation results, the actual locations of R&EAs coincided well with the estimated high probability areas, as confirmed by the values of Cohen's Kappa index of up to 64%, which indicate a reasonable level of agreement.

What Were the Major Factors That Controlled Mineralogical Similarities and Differences of Basaltic, Lherzolitic and Clinopyroxentic Martian Meteorites Within Each Group

NASA Technical Reports Server (NTRS)

Mikouchi, T.; Miyamoto, M.; McKay, G. A.

1998-01-01

Twelve martian meteorites that have been re- covered so far are classified into five groups (basalt, lherzolite, clinopyroxenite, dunite, and orthopyroxenite) mainly from petrology and chemistry. Among them, the dunite and orthopyroxenite groups consist of only one meteorite each (dunite: Chassigny, orthopyroxenite: ALH 84001). The basalt group is the largest group and consists of four meteorites (Shergotty, Zagani, EETA 79001, and QUE 94201). The lherzolitic and clinopyroxenitic groups include three meteorites each (Lherzolite: ALH 77005, LEW 88516, and Y793605, clinopyroxenite: Nakhla, Governador Valadares, and Lafayette). These meteorites within each group are generally similar to the others, but none of them is paired with the others. In this abstract, we discuss the major factors that controlled mineralogical similarities and differences of basaltic, lherzolitic, and clinopyroxenitic meteorites within each group. This may help in understanding their petrogenesis and original locations on Mars in general.

Xe-129 - Xe-128 and Ar-40 - Ar-39 chronology of two Antarctic enstatite meteorites

NASA Technical Reports Server (NTRS)

Honda, M.; Bernatowicz, T. J.; Podosek, F. A.

1983-01-01

Xe-129 - Xe-128 and Ar-40 - Ar-39 analyses has been performed on two Antarctic enstatite meteorites, the chondrite Y-691 and the aubrite (enstatite achondrite) ALH-78113. Both meteorites have complex Ar-40 - Ar-39 release patterns to which no unambiguous age assignment is possible. Both give apparently satisfactory Xe-129 - Xe-128 correlations corresponding to unusual ages. The I-Xe age of the chondrite Y-691 is 16 Ma after Bjurbole, not unusual for chondrites in general but 10 Ma later than previously known ages for enstatite chondrites. The I-Xe age of the aubrite ALH-78113 is 210 Ma after Bjurbole, the latest age (rather than a limit) so far observed by the I-Xe technique, but this age assignment must be considered tentative because of the possibility that it is significantly influenced by terrestrial I contamination.

Covariant C and O Isotope Trends in Arctic Carbonate Crusts and ALH 84001: Potential Biomarker or Indicator of Cryogenic Formation Environment?

NASA Technical Reports Server (NTRS)

Socki, Richard A.; Niles, Paul B.; Blake, Weston; Leveille, Richard

2009-01-01

This work seeks to use the chemical, isotopic, and mineralogical characteristics of secondary carbonate minerals produced during brief aqueous events to identify the conditions of the aqueous environment in which they formed. Liquid water near the surface of Mars is subject to either rapid freezing and/or evaporation. These processes are also active on Earth, and produce secondary minerals that have complex chemical, mineralogical, and isotopic textures and compositions that can include covariant relationships between Delta C-13 (sub VPDB) and delta O-18 (sub VSMOW). The extremely well studied four billion year old carbonates preserved in martian meteorite ALH 84001 also show covariant delta C-13 and delta O-18 compositions, but these variations are manifested on a micro-scale in a single thin section while the variation observed so far in terrestrial carbonates is seen between different hand samples.

Astronaut - Shepard - MR-3

NASA Image and Video Library

1961-01-01

S61-02785 (5 May 1961) --- Astronaut Alan B. Shepard Jr. in his pressure suit is seated in a reclining chair while a technician checks communications equipment in his helmet. He is in the suiting trailer before the Mercury-Redstone 3 (MR-3) flight, the first American manned spaceflight. Photo credit: NASA or National Aeronautics and Space Administration

Action Learning at Work.

ERIC Educational Resources Information Center

Mumford, Alan, Ed.

This book contains 34 papers examining the theory, process, and outcomes of action learning at work. The following papers are included: "An Introduction to the Text" (Alan Mumford); "The Learning Equation" (Reg Revans); "Action Learning as a Vehicle for Learning" (Alan Mumford); "Placing Action Learning and…

Effect of separate and combined exposure of selenium and diazinon on rat sperm motility by computer assisted semen analysis.

PubMed

Toman, Robert; Hluchy, Svatoslav; Cabaj, Michal; Massanyi, Peter; Roychoudhury, Shubhadeep; Tunegova, Martina

2016-12-01

Effects of selenium (Se) and diazinon (DZN) on sperm motility parameters in rats were investigated. Male rats received a separate dose of Se (2mgkg -1 b.w., intraperitoneally, 5mgL -1 , per os in drinking water), diazinon (20mgkg -1 b.w., intraperitoneally, 40mgL -1 , per os in drinking water), and in combination (Se+DZN) with the same dosage as in the separate administration. 36h an intraperitoneal (i.p.) and after 90days of per oral (p.o.) exposure, thirteen parameters of sperm motility were evaluated using a Computer Assisted Sperm Analyzer (CASA). Almost all the evaluated sperm motility parameters significantly decreased in Se p.o. exposed groups. In the Se i.p. group decrease was noted only in beat cross frequency (BCF) and progressive motility. Significant decline in the sperm motility, progressive motility, BCF and increase in amplitude of lateral head displacement (ALH) were recorded after DZN i.p. administration. In DZN p.o. group, significant increase in ALH, velocity average path (VAP) and curvilinear velocity (VCL) but decrease in progressive motility and BCF was detected. Se+DZN i.p. administration caused a significant decrease in motility, progressive motility and BCF. Per oral administration of Se+DZN decreased all motility parameters except LIN, WOB and ALH. Sperm abnormalities increased in all experimental conditions. Se and DZN negatively affected sperm structure and function in separate doses or in combination. No protective effect of Se was observed. Copyright © 2016 Elsevier GmbH. All rights reserved.

Cryogenic Calcite: A Morphologic and Isotopic Analog to the ALH84001 Carbonates

NASA Technical Reports Server (NTRS)

Niles, P. B.; Leshin, L. A.; Socki, R. A.; Guan, Y.; Ming, D. W.; Gibson, E. K.

2004-01-01

Martian meteorite ALH84001 carbonates preserve large and variable microscale isotopic compositions, which in some way reflect their formation environment. These measurements show large variations (>20%) in the carbon and oxygen isotopic compositions of the carbonates on a 10-20 micron scale that are correlated with chemical composition. However, the utilization of these data sets for interpreting the formation conditions of the carbonates is complex due to lack of suitable terrestrial analogs and the difficulty of modeling under non-equilibrium conditions. Thus, the mechanisms and processes are largely unknown that create and preserve large microscale isotopic variations in carbonate minerals. Experimental tests of the possible environments and mechanisms that lead to large microscale isotopic variations can help address these concerns. One possible mechanism for creating large carbon isotopic variations in carbonates involves the freezing of water. Carbonates precipitate during extensive CO2 degassing that occurs during the freezing process as the fluid s decreasing volume drives CO2 out. This rapid CO2 degassing results in a kinetic isotopic fractionation where the CO2 gas has a much lighter isotopic composition causing an enrichment of 13C in the remaining dissolved bicarbonate. This study seeks to determine the suitability of cryogenically formed carbonates as analogs to ALH84001 carbonates. Specifically, our objective is to determine how accurately models using equilibrium fractionation factors approximate the isotopic compositions of cryogenically precipitated carbonates. This includes determining the accuracy of applying equilibrium fractionation factors during a kinetic process, and determining how isotopic variations in the fluid are preserved in microscale variations in the precipitated carbonates.

Organic Carbon Exists in Mars Meteorites: Where is it on the Martian Surface?

NASA Technical Reports Server (NTRS)

McKay, D. S.; Clemett, S. J.; Gibson, E. K., Jr.; Thomas-Keprta, K. L.; Wentworth, S. J.

2010-01-01

The search for organic carbon on Mars has been a major challenge. The first attempt was the Viking GC-MS in situ experiment which gave inconclusive results at two sites oil. After the discovery that the SNC meteorites were from Mars, reported C isotopic compositional information which suggested a reduced C component present in the Martian meteorites reported the presence of reduced C components (i.e., polycyclic aromatic hydrocarbons) associated with the carbonate globules in ALH84001. Jull et al. noted in Nakhla there was acid insoluble C component present with more than 75% of its C lacking any C-14, which is modern-day terrestrial carbon. This C fraction was believed to be either indigenous martian or ancient meteoritic carbon. Fisk et al. have shown textural evidence along with C-enriched areas within fractures in Nakhla and ALH84001. Westall et al. have shown the presence of a large irregular fragment of organic material completely embedded within a chip of ALH84001. Interior samples from the Naklnla SNC made available by the British Museum of Natural History, were analyzed. Petrographic examination of Nakhla showed evidence of fractures (approx.0.5 microns wide) filled with dark brown to black dendritic material with characteristics similar to those observed by. Iddingsite is also present along fractures in olivine. Fracture filling and dendritic material was examined by SEM-EDX, TEM-EDX, Focused Electron Beam microscopy, Laser Raman Spectroscopy, Nano-SIMS Ion Micro-probe, and Stepped-Combustion Static Mass Spectrometry. Observations from the first three techniques are discussed.

Comparison of retinal vessel measurements using adaptive optics scanning laser ophthalmoscopy and optical coherence tomography.

PubMed

Arichika, Shigeta; Uji, Akihito; Ooto, Sotaro; Muraoka, Yuki; Yoshimura, Nagahisa

2016-05-01

We compared adaptive optics scanning laser ophthalmoscopy (AOSLO) and optical coherence tomography (OCT) vessel caliber measurements. AOSLO videos were acquired from 28 volunteers with healthy eyes. Artery measurements were made 0.5-1 disc diameters away from the optic disc margin. Individual segmented retinal arterial caliber was measured in synchronization with cardiac pulsation and averaged to obtain final horizontal retinal arterial caliber (ACH) and horizontal retinal arterial lumen (ALH). All OCT images were obtained with the Spectralis OCT, a spectral-domain OCT system. Vertical retinal arterial caliber (ACV) and vertical retinal arterial lumen (ALV) were measured on the same artery measured with AOSLO. Measurements made with the two imaging systems were compared. Average ACH, measured with AOSLO, was 123.4 ± 11.2 and average ALH was 101.8 ± 10.2 µm. Average ACV, measured with OCT, was 125.5 ± 11.4 and average ALV was 99.1 ± 10.6 µm. Both arterial caliber (r = 0.767, p < 0.0001) and arterial lumen (r = 0.81, p < 0.0001) measurements were significantly correlated between imaging modalities. Additionally, ACH and ACV were not significantly different (p = 0.16). However, ALH measurements were significantly higher than ALV measurements (p = 0.03). Vessel measurements made with AOSLO and OCT were well correlated. Moreover, plasma is visible and distinguishable from the retinal vessel wall in AOSLO images but not in OCT images. Therefore, AOSLO may measure vessel width more precisely than OCT.

Microstructure and Thermal History of Metal Particles in CH Chondrites

NASA Astrophysics Data System (ADS)

Goldstein, J. I.; Jones, R. H.; Kotula, P. G.; Michael, J. R.

2005-03-01

This paper provides detailed microstructural and microchemical information at the nm to µm scale (SEM, EPMA, TEM, EBSD) for a select suite of metal particles in four CH chondrites, ALH 85085, PAT 91546, Acfer 214, NWA 739.

Modeling the contributions of phytoplankton and non-algal particles to spectral scattering properties in near-shore and lagoon waters

NASA Astrophysics Data System (ADS)

Vadakke-Chanat, Sayoob; Shanmugam, Palanisamy

2017-03-01

Particular attention was focused on modeling the spectral scattering properties of phytoplankton (bph(λ)) and non-algal particles (detrital organic and inorganic sediments bNAP(λ)) from absorption and attenuation measurements in near-shore and lagoon waters. The absorption line height (aLH(676)) measured above a linear background between 648 nm and 714 nm in particulate and dissolved organic matter absorption spectra (ap(λ)) is a spectral feature that is primarily associated with the chlorophyll with significantly less pigment package effect compared to the blue peak, and hence it is solely attributed to the phytoplankton absorption (aph). The correlation of aph(λ) with bph(λ) in terms of the spectral shape and the relation of aLH(676) with chlorophyll concentration hold the key to derive bph(648) from the aLH(676) measurements. bNAP(648) values are then determined by subtracting the bph(648) from bp(648), allowing the power-law model to derive the bNAP(λ). In-situ determination of bph (λ) is subsequently achieved by subtracting the featureless bNAP(λ) from bp(λ) provided by the ac-s sensor. These data form the basis for the development of models for independent estimates of bph(λ) and bNAP(λ) based on the measurements of aLH and suspended sediment concentration or turbidity. The validity of this method was demonstrated in a wide variety of samples from coastal and inland environments. Comparison of the modeled and measured spectral variations of bph(λ) showed the mean relative percent difference between these two data to be within 20%. bNAP(λ) predictions also had an error a few percent and the correlation coefficient close to unity. When comparing the modeled bph(λ) with laboratory culture data, the results were exceptionally good although discrepancies in size and refractive index of cells of monospecific lab culture samples and natural assemblages due to the simultaneous presence of different species. The proposed approach and models are highly instrumental in investigating the scattering properties of phytoplankton and non-living constituents, and will provide new tools for improving our current understanding of particle dynamics, advancing biogeochemical and ecosystem modeling, and assessing phytoplankton blooms and sediment plumes within inland and coastal environments.

Skylab-3 Mission Onboard Photograph - Astronaut Bean working on Experiment S019

NASA Technical Reports Server (NTRS)

1973-01-01

This Skylab-3 mission onboard photograph shows Astronaut Alan Bean operating the Ultraviolet (UV) Stellar Astronomy experiment (S019) in the Skylab Airlock Module. The S019, a camera with a prism for UV star photography, studied the UV spectra of early-type stars and galaxies.

Expert Systems on Multiprocessor Architectures. Volume 2. Technical Reports

DTIC Science & Technology

1991-06-01

Report RC 12936 (#58037). IBM T. J. Wartson Reiearch Center. July 1987. � Alan Jay Smith. Cache memories. Coniputing Sitrry., 1.1(3): I.3-5:30...basic-shared is an instrument for ashared memory design. The components panels are processor- qload-scrolling-bar-panel, memory-qload-scrolling-bar-panel

Astronaut Alan Bean participates in lunar surface simulation

NASA Image and Video Library

1969-10-29

S69-56059 (24 Oct. 1969) --- Astronaut Alan L. Bean, lunar module pilot of the Apollo 12 lunar landing mission, participates in lunar surface simulation training in Building 29 at the Manned Spacecraft Center (MSC). Bean is strapped to a one-sixth gravity simulator.

Variability of surface and underwater nocturnal spectral irradiance with the presence of clouds in urban and peri-urban wetlands.

PubMed

Secondi, Jean; Dupont, Valentin; Davranche, Aurélie; Mondy, Nathalie; Lengagne, Thierry; Théry, Marc

2017-01-01

Artificial light at night (ALAN) is an increasing phenomenon worldwide. It causes a wealth of biological and ecological effects that may eventually affect populations and ecosystems. Despite the growing concern about ALAN, little is known about the light levels species are exposed to at night, especially for wetlands and underwater habitats. We determined nocturnal irradiance in urban and peri-urban wetlands above and under water, and assessed the effect of cloud cover on the variability of ALAN across the urban gradient. Even in aquatic habitats, cloud cover could increase irradiance beyond values observed during clear full moon nights. We report a negative relationship between baseline irradiance and the increase in irradiance during overcast nights. According to this result and previous studies, we propose that the change in the variation regime of ALAN between the urban center and rural land at its periphery is a usual feature. We discuss the ecological and evolutionary implications of this spatial variation in the urban and peri-urban environment.

Rubidium-Strontium Formation Age of Allan Hills 84001 Carbonates

NASA Technical Reports Server (NTRS)

Borg, L. E.; Nyquist, L. E.; Shih, C.-Y.; Weismann, H.; Reese, Y.; Connelly, J. N.

1998-01-01

Our preferred age for the formation of carbonates in the martian meteorite ALH 84001 is 3.90 plus or minus 0.04 Ga for Lambda (Rubidium 87) equals 0.01402 Ga (exp -1), or 3.85 plus or minus 0.04 Ga for Lambda (Rubidium 87) = 0.0142 Ga(exponent -1). This age is determined by a three-point Rb-Sr isochron defined by leachates of high-graded carbonate-rich material. Major cation and especially phosphorous analyses of the leachates permit contributions from igneous whitlockite to be recognized for low-acidity leachates, and the corresponding data are omitted from the isochron. Data for the two highest acidity leachates plot close to the preferred isochron, but are omitted because we believe they contain contributions leached from the pyroxene substrate on which most of the carbonates are found. Nevertheless, the isochron age for all five highest-acidity leachates is 3.94 plus or minus 0.04 Ga, and is within error of the age obtained for the more restricted data set. All leachates used to define the isochron have major cation compositions that are singular to those obtained by microprobe analyses of the carbonate rosettes and are consistent with progressive digestion of the carbonates according to their composition. The age thus obtained for the carbonates is about 600 m.y. younger than the crystalization age of ALH 84001 determined by Sm-Nd analyses but is within error limits of the age of impact metamorphism inferred from the Rb-Sr and Ar-Ar systematics of silicates. which yield ages of 3.85 plus or minus 0.05 Ga and 4.05- 3.80 Ga to 4.3-3.8 Ga, respectively. Similarities between the carbonate crystallization age and the age of impact metamorphism as determined by Ar-Ar and Rb-Sr suggest that the carbonate formation is impact-related. Nevertheless, both high and low- temperature scenarios for the origin of the carbonates are possible.

Calculation of the 13C NMR shieldings of the C0 2 complexes of aluminosilicates

NASA Astrophysics Data System (ADS)

Tossell, J. A.

1995-04-01

13C NMR shieldings have been calculated using the random-phase-approximation, localized-orbital local-origins version of ab initio coupled Hartree-Fuck perturbation theory for CO 2 and and for several complexes formed by the reaction of CO 2 with molecular models for aluminosilicate glasses, H 3TOT'H3 3-n, T,T' = Si,Al. Two isomeric forms of the CO 2-aluminosilicate complexes have been considered: (1) "CO 2-like" complexes, in which the CO 2 group is bound through carbon to a bridging oxygen and (2) "CO 3-like" complexes, in which two oxygens of a central CO 3 group form bridging bonds to the two TH 3 groups. The CO 2-like isomer of CO 2-H 3SiOSiH 3 is quite weakly bonded and its 13C isotropic NMR shielding is almost identical to that in free CO 2. As Si is progressively replaced by Al in the - H terminated aluminosilicate model, the CO 2-like isomers show increasing distortion from the free CO 2 geometry and their 13C NMR shieldings decrease uniformly. The calculated 13C shielding value for H 3AlO(CO 2)AlH 3-2 is only about 6 ppm larger than that calculated for point charge stabilized CO 3-2. However, for a geometry of H 3SiO(CO 2) AlH 3-1, in which the bridging oxygen to C bond length has been artificially increased to that found in the - OH terminated cluster (OH) 3SiO(CO 2)Al(OH) 3-1, the calculated 13C shielding is almost identical to that for free CO 2. The CO 3-like isomers of the CO 2-aluminosili-cate complexes show carbonate like geometries and 13C NMR shieldings about 4-9 ppm larger than those of carbonate for all T,T' pairs. For the Si,Si tetrahedral atom pair the CO 2-like isomer is more stable energetically, while for the Si,Al and Al,Al cases the CO 3-like isomer is more stable. Addition of Na + ions to the CO 3-2 or H 3AlO(CO 2)AlH 3-2 complexes reduces the 13C NMR shieldings by about 10 ppm. Complexation with either Na + or CO 2 also reduces the 29Si NMR shieldings of the aluminosilicate models, while the changes in 27Al shielding with Na + or CO 2 complexation are much smaller. Complexation with CO 2 greatly increases the electric field gradient at the bridging oxygen of H 3AlOAlH 3-2, raising it to a value similar to that found for SiOSi linkages. Comparison of these results with the experimental 13C NMR spectra support the formation of CO 2-like complexes at SiOSi bridges in albite glasses and CO 3-like complexes at SiOAl and AlOAl bridges in albite and nepheline glasses. Changes in the calculated shieldings as Na + ions are added to the complexes suggest that some of the observed complexes may be similar in their CO 2-aluminosilicate interactions, but different with respect to the positions of the charge-compensating Na + ions.

Aqueous Chemical Modeling of Sedimentation on Early Mars with Application to Surface-Atmosphere Evolution

NASA Technical Reports Server (NTRS)

Catling, David C.

2004-01-01

This project was to investigate models for aqueous sedimentation on early Mars from fluid evaporation. Results focused on three specific areas: (1) First, a fluid evaporation model incorporating iron minerals was developed to compute the evaporation of a likely solution on early Mars derived from the weathering of mafic rock. (2) Second, the fluid evaporation model was applied to salts within Martian meteorites, specifically salts in the nakhlites and ALH84001. Evaporation models were found to be consistent with the mineralogy of salt assemblages-anhydrite, gypsum, Fe-Mg-Ca carbonates, halite, clays-- and the concentric chemical fractionation of Ca-to Mg-rich carbonate rosettes in ALH84001. We made progress in further developing our models of fluid concentration by contributing to updating the FREZCHEM model. (3) Third, theoretical investigation was done to determine the thermodynamics and kinetics involved in the formation of gray, crystalline hematite. This mineral, of probable ancient aqueous origin, has been observed in several areas on the surface of Mars by the Thermal Emission Spectrometer on Mars Global Surveyor. The "Opportunity" Mars Exploration Rover has also detected gray hematite at its landing site in Meridiani Planum. We investigated how gray hematite can be formed via atmospheric oxidation, aqueous precipitation and subsequent diagenesis, or hydrothermal processes. We also studied the geomorphology of the Aram Chaos hematite region using Mars Orbiter Camera (MOC) images.

Carbonates in the Martian meteorite Allan Hills 84001 formed at 18 ± 4 °C in a near-surface aqueous environment

PubMed Central

Halevy, Itay; Fischer, Woodward W.; Eiler, John M.

2011-01-01

Despite evidence for liquid water at the surface of Mars during the Noachian epoch, the temperature of early aqueous environments has been impossible to establish, raising questions of whether the surface of Mars was ever warmer than today. We address this problem by determining the precipitation temperature of secondary carbonate minerals preserved in the oldest known sample of Mars’ crust—the approximately 4.1 billion-year-old meteorite Allan Hills 84001 (ALH84001). The formation environment of these carbonates, which are constrained to be slightly younger than the crystallization age of the rock (i.e., 3.9 to 4.0 billion years), has been poorly understood, hindering insight into the hydrologic and carbon cycles of earliest Mars. Using “clumped” isotope thermometry we find that the carbonates in ALH84001 precipitated at a temperature of approximately 18 °C, with water and carbon dioxide derived from the ancient Martian atmosphere. Furthermore, covarying carbonate carbon and oxygen isotope ratios are constrained to have formed at constant, low temperatures, pointing to deposition from a gradually evaporating, subsurface water body—likely a shallow aquifer (meters to tens of meters below the surface). Despite the mild temperatures, the apparently ephemeral nature of water in this environment leaves open the question of its habitability. PMID:21969543

Thermally metamorphosed carbonaceous chondrites from data for thermally mobile trace elements

NASA Astrophysics Data System (ADS)

Wang, Ming-Sheng; Lipschutz, Michael E.

1998-11-01

We report RNAA data for U, Co, Au, Sb, Ga, Rb, Cs, Se, Ag, Te, Zn, In, Bi, Tl and Cd (ordered by increasing ease of vaporization and loss from Murchison CM2 chondrite during open-system heating) in 9 Antarctic C2 and C3 chondrites. These meteorites exhibit properties (obtained by reflectance spectroscopy, oxygen isotope mass spectrometry and/or mineralogy-petrology) suggesting thermal metamorphism in their parent bodies. Five of these (Asuka 881655, Yamato (Y) 793495, Y-790992, PCA 91008 and Y-86789, paired with Y-86720) exhibit significant depletion of the most thermally-mobile 1-5 trace elements consistent with open-system loss during extended parent body heating under conditions duplicated by week-long heating of Murchison C2 chondrite heated at 500-700 deg C in a low pressure (initially 10-5 atm) H atmosphere. From earlier data, three other C3 chondrites - Allan Hills (ALH) 81003, ALH 85003 and Lewis Cliffs 85332 - show significant Cd depletion. Nine additional C2 and C3 chondrites show no evidence of mobile trace element depletion - including Y-793321, which by all other criteria was mildly metamorphosed thermally. Either metamorphism of these nine occurred under closed conditions and/or alteration took place under such mild conditions that even Cd could not be lost. The RNAA data suggest that 10 of the 46 Antarctic carbonaceous chondrites (including 4 of 37 from Victoria Land and 6 of 9 from Queen Maud Land) exhibit open-system loss of at least some thermally mobile trace elements by heating in their parent bodies while none of the 25 non-Antarctic falls experienced this. These results are consistent with the idea that the Antarctic sampling of near-Earth material differs from that being sampled today.

Lunar and Planetary Science XXXV: Astrobiology

NASA Technical Reports Server (NTRS)

2004-01-01

The presentations in this session are: 1. A Prototype Life Detection Chip 2. The Geology of Atlantis Basin, Mars, and Its Astrobiological Interest 3. Collecting Bacteria Together with Aerosols in the Martian Atmosphere by the FOELDIX Experimental Instrument Developed with a Nutrient Detector Pattern: Model Measurements of Effectivity 4. 2D and 3D X-ray Imaging of Microorganisms in Meteorites Using Complexity Analysis to Distinguish Field Images of Stromatoloids from Surrounding Rock Matrix in 3.45 Ga Strelley Pool Chert, Western Australia 4. Characterization of Two Isolates from Andean Lakes in Bolivia Short Time Scale Evolution of Microbiolites in Rapidly Receding Altiplanic Lakes: Learning How to Recognize Changing Signatures of Life 5. The Effect of Salts on Electrospray Ionization of Amino Acids in the Negative Mode 6. Determination of Aromatic Ring Number Using Multi-Channel Deep UV Native Fluorescence 7. Microbial D/H Fractionation in Extraterrestrial Materials: Application to Micrometeorites and Mars 8. Carbon Isotope Characteristics of Spring-fed Iron-precipitating Microbial Mats 9. Amino Acid Survival Under Ambient Martian Surface UV Lighting Extraction of Organic Molecules from Terrestrial Material: Quantitative Yields from Heat and Water Extractions 10. Laboratory Detection and Analysis of Organic Compounds in Rocks Using HPLC and XRD Methods 11. Thermal Decomposition of Siderite-Pyrite Assemblages: Implications for Sulfide Mineralogy in Martian Meteorite ALH84001 Carbonate Globules 12. Determination of the Three-Dimensional Morphology of ALH84001 and Biogenic MV-1 Magnetite: Comparison of Results from Electron Tomography and Classical Transmission Electron Microscopy 13. On the Possibility of a Crypto-Biotic Crust on Mars Based on Northern and Southern Ringed Polar Dune Spots 14. Comparative Planetology of the Terrestrial Inner Planets: Implications for Astrobiology 15. A Possible Europa Exobiology 16. A Possible Biogeochemical Model for Titan

New derivatives of 3,4-dihydroisoquinoline-3-carboxylic acid with free-radical scavenging, D-amino acid oxidase, acetylcholinesterase and butyrylcholinesterase inhibitory activity.

PubMed

Solecka, Jolanta; Guśpiel, Adam; Postek, Magdalena; Ziemska, Joanna; Kawęcki, Robert; Lęczycka, Katarzyna; Osior, Agnieszka; Pietrzak, Bartłomiej; Pypowski, Krzysztof; Wyrzykowska, Agata

2014-09-30

A series of 3,4-dihydroisoquinoline-3-carboxylic acid derivatives were synthesised and tested for their free-radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS·+), superoxide anion radical (O2·-) and nitric oxide radical (·NO) assays. We also studied d-amino acid oxidase (DAAO), acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activity. Almost each of newly synthesised compounds exhibited radical scavenging capabilities. Moreover, several compounds showed moderate inhibitory activities against DAAO, AChE and BuChE. Compounds with significant free-radical scavenging activity may be potential candidates for therapeutics used in oxidative-stress-related diseases.

Astronaut Alan Bean deploys Lunar Surface Magnetometer on lunar surface

NASA Image and Video Library

1969-11-19

Astronaut Alan L. Bean, lunar module pilot, deploys the Lunar Surface Magnetometer (LSM) during the first Apollo 12 extravehicular activity on the Moon. The LSM is a component of the Apollo Lunar Surface Experiments Package (ALSEP). The Lunar Module can be seen in the left background.

77 FR 74518 - Alan T. Waterman Award Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-14

... NATIONAL SCIENCE FOUNDATION Alan T. Waterman Award Committee; Notice of Meeting In accordance with the Federal Advisory Committee Act (Pub. L. 92- 463, as amended), the National Science Foundation..., 2013, 8:30a.m.-1:30 p.m. Place: National Science Foundation, Arlington, Virginia 22230. Type of Meeting...

Astronaut Alan Bean deploys Lunar Surface Magnetometer on lunar surface

NASA Technical Reports Server (NTRS)

1969-01-01

Astronaut Alan L. Bean, lunar module pilot, deploys the Lunar Surface Magnetometer (LSM) during the first Apollo 12 extravehicular activity on the Moon. The LSM is a component of the Apollo Lunar Surface Experiments Package (ALSEP). The Lunar Module can be seen in the left background.

Density functional theory study on aqueous aluminum-fluoride complexes: exploration of the intrinsic relationship between water-exchange rate constants and structural parameters for monomer aluminum complexes.

PubMed

Jin, Xiaoyan; Qian, Zhaosheng; Lu, Bangmei; Yang, Wenjing; Bi, Shuping

2011-01-01

Density functional theory (DFT) calculation is carried out to investigate the structures, (19)F and (27)Al NMR chemical shifts of aqueous Al-F complexes and their water-exchange reactions. The following investigations are performed in this paper: (1) the microscopic properties of typical aqueous Al-F complexes are obtained at the level of B3LYP/6-311+G**. Al-OH(2) bond lengths increase with F(-) replacing inner-sphere H(2)O progressively, indicating labilizing effect of F(-) ligand. The Al-OH(2) distance trans to fluoride is longer than other Al-OH(2) distance, accounting for trans effect of F(-) ligand. (19)F and (27)Al NMR chemical shifts are calculated using GIAO method at the HF/6-311+G** level relative to F(H(2)O)(6)(-) and Al(H(2)O)(6)(3+) references, respectively. The results are consistent with available experimental values; (2) the dissociative (D) activated mechanism is observed by modeling water-exchange reaction for [Al(H(2)O)(6-i)F(i)]((3-i)+) (i = 1-4). The activation energy barriers are found to decrease with increasing F(-) substitution, which is in line with experimental rate constants (k(ex)). The log k(ex) of AlF(3)(H(2)O)(3)(0) and AlF(4)(H(2)O)(2)(-) are predicted by three ways. The results indicate that the correlation between log k(ex) and Al-O bond length as well as the given transmission coefficient allows experimental rate constants to be predicted, whereas the correlation between log k(ex) and activation free energy is poor; (3) the environmental significance of this work is elucidated by the extension toward three fields, that is, polyaluminum system, monomer Al-organic system and other metal ions system with high charge-to-radius ratio.

Fission Xenon on Mars

NASA Technical Reports Server (NTRS)

Mathew, K. J.; Marti, K.; Marty, B.

2002-01-01

Fission Xe components due to Pu-244 decay in the early history of Mars have been identified in nakhlites; as in the case of ALH84001 and Chassigny the fission gas was assimilated into indigenous solar-type Xe. Additional information is contained in the original extended abstract.

New natural product -an efficient antimicrobial applications of new newly synthesized pyrimidine derivatives by the electrochemical oxidation of hydroxyl phenol in the presence of 2-mercapto-6-(trifluoromethyl) pyrimidine-4-ol as nucleophile.

PubMed

Khan, Zia Ul Haq; Khan, Amjad; Wan, Pingyu; Khan, Arif Ullah; Tahir, Kamran; Muhammad, Nawshad; Khan, Faheem Ullah; Shah, Hidayat Ullah; Khan, Zia Ullah

2018-05-01

Some new pyrimidine derivatives have been synthesised by electrochemical oxidation of catechol (1a) in the existence of 2-mercapto-6-(trifluoromethyl) pyrimidine-4-ol (3) as a nucleophile in aqueous solution using Cyclic Voltammetric and Controlled Potential Coulometry. The catechol has been oxidised to o-quinone through electrochemical method and participative in Michael addition reaction, leading to the development of some new pyrimidine derivatives. The products were achieved in good yield with high pureness. The mechanism of the reaction has been conformed from the Cyclic Voltammetric data and Controlled Potential Coulometry. After purification, the compounds were characterised using modern techniques. The synthesised materials were screened for antimicrobial actions using Gram positive and Gram negative strain of bacteria. These new synthesised pyrimidine derivatives showed very good antimicrobial activity.

Spatial distribution analysis of the OMI aerosol layer height: a pixel-by-pixel comparison to CALIOP observations

NASA Astrophysics Data System (ADS)

Chimot, Julien; Pepijn Veefkind, J.; Vlemmix, Tim; Levelt, Pieternel F.

2018-04-01

A global picture of atmospheric aerosol vertical distribution with a high temporal resolution is of key importance not only for climate, cloud formation, and air quality research studies but also for correcting scattered radiation induced by aerosols in absorbing trace gas retrievals from passive satellite sensors. Aerosol layer height (ALH) was retrieved from the OMI 477 nm O2 - O2 band and its spatial pattern evaluated over selected cloud-free scenes. Such retrievals benefit from a synergy with MODIS data to provide complementary information on aerosols and cloudy pixels. We used a neural network approach previously trained and developed. Comparison with CALIOP aerosol level 2 products over urban and industrial pollution in eastern China shows consistent spatial patterns with an uncertainty in the range of 462-648 m. In addition, we show the possibility to determine the height of thick aerosol layers released by intensive biomass burning events in South America and Russia from OMI visible measurements. A Saharan dust outbreak over sea is finally discussed. Complementary detailed analyses show that the assumed aerosol properties in the forward modelling are the key factors affecting the accuracy of the results, together with potential cloud residuals in the observation pixels. Furthermore, we demonstrate that the physical meaning of the retrieved ALH scalar corresponds to the weighted average of the vertical aerosol extinction profile. These encouraging findings strongly suggest the potential of the OMI ALH product, and in more general the use of the 477 nm O2 - O2 band from present and future similar satellite sensors, for climate studies as well as for future aerosol correction in air quality trace gas retrievals.

Rare Potassium-Bearing Mica in Allan Hills 84001: Additional Constraints on Carbonate Formation

NASA Technical Reports Server (NTRS)

Brearley, A. J.

1998-01-01

There have been presented several intriguing observations suggesting evidence of fossil life in martian orthopyroxenite ALH 84001. These exciting and controversial observations have stimulated extensive debate over the origin and history of ALH 84001, but many issues still remain unresolved. Among the most important is the question of the temperature at which the carbonates, which host the putative microfossils, formed. Oxygen- isotopic data, while showing that the carbonates are generally out of isotopic equilibria with the host rock, cannot constrain their temperature of formation. Both low- and high-temperature scenarios are plausible depending on whether carbonate growth occurred in an open or closed system. Petrographic arguments have generally been used to support a high-temperature origin but these appear to be suspect because they assume equilibrium between carbonate compositions that are not in contact. Some observations appear to be consistent with shock mobilization and growth from immiscible silicate-carbonate melts at high temperatures. Proponents of a low-temperature origin for the carbonates are hampered by the fact that there is currently no evidence of hydrous phases that would indicate low temperatures and the presence of a hydrous fluid during the formation of the carbonates. However, the absence of hydrous phases does not rule out carbonate formation at low temperatures, because the carbonate forming fluids may have been extremely CO2 rich, such that hydrous phases would not have been stabilized. In this study, I have carried out additional Transmission electron microscopy (TEM) studies of ALH-84001 and have found evidence of very rare phyllosilicates, which appear to be convincingly of pre-terrestrial origin. At present these observations are limited to one occurrence: further studies are in progress to determine if the phyllosilicates are more widespread.

Ameliorative Effect of Hexane Extract of Phalaris canariensis on High Fat Diet-Induced Obese and Streptozotocin-Induced Diabetic Mice

PubMed Central

Perez Gutierrez, Rosa Martha; Madrigales Ahuatzi, Diana; Horcacitas, Maria del Carmen; Garcia Baez, Efren; Cruz Victoria, Teresa; Mota-Flores, Jose Maria

2014-01-01

Obesity is one of the major factors to increase various disorders like diabetes. The present paper emphasizes study related to the antiobesity effect of Phalaris canariensis seeds hexane extract (Al-H) in high-fat diet- (HFD-) induced obese CD1 mice and in streptozotocin-induced mild diabetic (MD) and severely diabetic (SD) mice.AL-H was orally administered to MD and SD mice at a dose of 400 mg/kg once a day for 30 days, and a set of biochemical parameters were studied: glucose, cholesterol, triglycerides, lipid peroxidation, liver and muscle glycogen, ALP, SGOT, SGPT, glucose-6-phosphatase, glucokinase, hexokinase, SOD, CAT, GSH, GPX activities, and the effect on insulin level. HS-H significantly reduced the intake of food and water and body weight loss as well as levels of blood glucose, serum cholesterol, triglyceride, lipoprotein, oxidative stress, showed a protective hepatic effect, and increased HDL-cholesterol, serum insulin in diabetic mice. The mice fed on the high-fat diet and treated with AL-H showed inhibitory activity on the lipid metabolism decreasing body weight and weight of the liver and visceral adipose tissues and cholesterol and triglycerides in the liver. We conclude that AL-H can efficiently reduce serum glucose and inhibit insulin resistance, lipid abnormalities, and oxidative stress in MD and SD mice. Our results demonstrate an antiobesity effect reducing lipid droplet accumulation in the liver, indicating that its therapeutic properties may be due to the interaction plant components soluble in the hexane extract, with any of the multiple targets involved in obesity and diabetes pathogenesis. PMID:24523819

A robust robotic high-throughput antibody purification platform.

PubMed

Schmidt, Peter M; Abdo, Michael; Butcher, Rebecca E; Yap, Min-Yin; Scotney, Pierre D; Ramunno, Melanie L; Martin-Roussety, Genevieve; Owczarek, Catherine; Hardy, Matthew P; Chen, Chao-Guang; Fabri, Louis J

2016-07-15

Monoclonal antibodies (mAbs) have become the fastest growing segment in the drug market with annual sales of more than 40 billion US$ in 2013. The selection of lead candidate molecules involves the generation of large repertoires of antibodies from which to choose a final therapeutic candidate. Improvements in the ability to rapidly produce and purify many antibodies in sufficient quantities reduces the lead time for selection which ultimately impacts on the speed with which an antibody may transition through the research stage and into product development. Miniaturization and automation of chromatography using micro columns (RoboColumns(®) from Atoll GmbH) coupled to an automated liquid handling instrument (ALH; Freedom EVO(®) from Tecan) has been a successful approach to establish high throughput process development platforms. Recent advances in transient gene expression (TGE) using the high-titre Expi293F™ system have enabled recombinant mAb titres of greater than 500mg/L. These relatively high protein titres reduce the volume required to generate several milligrams of individual antibodies for initial biochemical and biological downstream assays, making TGE in the Expi293F™ system ideally suited to high throughput chromatography on an ALH. The present publication describes a novel platform for purifying Expi293F™-expressed recombinant mAbs directly from cell-free culture supernatant on a Perkin Elmer JANUS-VariSpan ALH equipped with a plate shuttle device. The purification platform allows automated 2-step purification (Protein A-desalting/size exclusion chromatography) of several hundred mAbs per week. The new robotic method can purify mAbs with high recovery (>90%) at sub-milligram level with yields of up to 2mg from 4mL of cell-free culture supernatant. Copyright © 2016 Elsevier B.V. All rights reserved.

Alan Bean Art Exhibit

NASA Image and Video Library

2009-07-19

Former NASA Astronaut and U.S. Senator John Glenn is seen at the opening of the exhibit "Alan Bean: Painting Apollo, First Artist on Another World" at the National Air and Space Museum, Monday, July 20, 2009 in Washington. The show opening coincided with the 40th anniversary celebration of Apollo. Photo Credit: (NASA/Carla Cioffi)

Preventing Terror Attacks in the Homeland: A New Mission for State and Local Police

DTIC Science & Technology

2005-09-01

18 Dale Couprie, Alan Goodbrand, Bin Li, and David Zhu, “ Soft Systems Methodology ,” Department of Computer Science (University of Calgary, 2002...Activities Authorization Act.” (50 USC. 403-1). June 2005. Couprie, Dale, Alan Goodbrand, Bin Li, and David Zhu. “ Soft Systems Methodology .” Department

A Consumer's Guide to High School History Textbooks

ERIC Educational Resources Information Center

Ravitch, Diane

2004-01-01

This document reviews a dozen history textbooks. The following American History textbooks are reviewed: (1) Joyce Appleby, Alan Brinkley, and James M. McPherson, The American Journey: Building a Nation (Glencoe, 2003), and Joyce Appleby, Alan Brinkley, Albert S. Broussard, James M. McPherson, and Donald A. Ritchie, The American Republic Since 1877…

40 Years in Applied Linguistics: An Interview with Alan Davies

ERIC Educational Resources Information Center

Kunnan, Antony John

2005-01-01

This article presents an interview with Professor Alan Davies who was born in Wales, studied at Oxford University and Birmingham University, and taught in Scotland at the University of Edinburgh, completing 40 years this year. Professor Davies has travelled widely to give invited talks and seminars, participate in applied linguistics conferences,…

Challenging the Status Quo: Alan Pifer and Higher Education Reform in Colonial Nigeria

ERIC Educational Resources Information Center

Anyanwu, Ogechi E.

2013-01-01

The historiography of higher education in Nigeria has not fully accounted for Alan Pifer's crucial contributions in reforming the elitist British higher education tradition in colonial Nigeria. Through qualitative analysis of mostly primary sources acquired from the Rare Book and Manuscript Library in Columbia University, this article argues that…

Variability of surface and underwater nocturnal spectral irradiance with the presence of clouds in urban and peri-urban wetlands

PubMed Central

Dupont, Valentin; Davranche, Aurélie; Mondy, Nathalie; Lengagne, Thierry; Théry, Marc

2017-01-01

Artificial light at night (ALAN) is an increasing phenomenon worldwide. It causes a wealth of biological and ecological effects that may eventually affect populations and ecosystems. Despite the growing concern about ALAN, little is known about the light levels species are exposed to at night, especially for wetlands and underwater habitats. We determined nocturnal irradiance in urban and peri-urban wetlands above and under water, and assessed the effect of cloud cover on the variability of ALAN across the urban gradient. Even in aquatic habitats, cloud cover could increase irradiance beyond values observed during clear full moon nights. We report a negative relationship between baseline irradiance and the increase in irradiance during overcast nights. According to this result and previous studies, we propose that the change in the variation regime of ALAN between the urban center and rural land at its periphery is a usual feature. We discuss the ecological and evolutionary implications of this spatial variation in the urban and peri-urban environment. PMID:29117235

China Report, Economic Affairs, No. 334

DTIC Science & Technology

1983-05-05

stations and 33 county artificial insemination and veterinary diagnostic stations, thereby taking the first steps toward setting up a...lanes between Erhuang road and Sanhuang road and build main roads leading to Huangchun hk and Changping, two satellite towns. In the next 3 years

Mercury Project

NASA Image and Video Library

1963-09-09

Astronaut Alan B. Shepard, one of the original seven astronauts for Mercury Project selected by NASA on April 27, 1959. The Freedom 7 spacecraft boosted by Mercury-Redstone vehicle for the MR-3 mission made the first marned suborbital flight and Astronaut Shepard became the first American in space.

Does artificial light-at-night exposure contribute to the worldwide obesity pandemic?

PubMed

Rybnikova, N A; Haim, A; Portnov, B A

2016-05-01

Worldwide overweight and obesity rates are on the rise, with about 1 900 billion adults being defined as overweight and about 600 million adults being defined as obese by the World Health Organization (WHO). Increasing exposure to artificial light-at-night (ALAN) may influence body mass, by suppression of melatonin production and disruption of daily rhythms, resulting in physiological or behavioral changes in the human body, and may thus become a driving force behind worldwide overweight and obesity pandemic. We analyzed most recent satellite images of night time illumination, available from the US Defense Meteorological Satellite Program (DMSP), combining them with country-level data on female and male overweight and obesity prevalence rates, reported by the WHO. The study aims to identify and measure the strength of association between ALAN and country-wide overweight and obesity rates, controlling for per capita GDP, level of urbanization, birth rate, food consumption and regional differences. ALAN emerged as a statistically significant and positive predictor of overweight and obesity (t>1.97; P<0.05), helping to explain, together with other factors, about 70% of the observed variation of overweight and obesity prevalence rates among females and males in more than 80 countries worldwide. Regional differences in the strength of association between ALAN and excessive body mass are also noted. This study is the first population-level study that confirms the results of laboratory research and cohort studies in which ALAN was found to be a contributing factor to excessive body mass in humans.

The reactivity of sodium alanates with O[2], H[2]O, and CO[2] : an investigation of complex metal hydride contamination in the context of automotive systems.

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

Dedrick, Daniel E.; Bradshaw, Robert W.; Behrens, Richard, Jr.

2007-08-01

Safe and efficient hydrogen storage is a significant challenge inhibiting the use of hydrogen as a primary energy carrier. Although energy storage performance properties are critical to the success of solid-state hydrogen storage systems, operator and user safety is of highest importance when designing and implementing consumer products. As researchers are now integrating high energy density solid materials into hydrogen storage systems, quantification of the hazards associated with the operation and handling of these materials becomes imperative. The experimental effort presented in this paper focuses on identifying the hazards associated with producing, storing, and handling sodium alanates, and thus allowingmore » for the development and implementation of hazard mitigation procedures. The chemical changes of sodium alanates associated with exposure to oxygen and water vapor have been characterized by thermal decomposition analysis using simultaneous thermogravimetric modulated beam mass spectrometry (STMBMS) and X-ray diffraction methods. Partial oxidation of sodium alanates, an alkali metal complex hydride, results in destabilization of the remaining hydrogen-containing material. At temperatures below 70 C, reaction of sodium alanate with water generates potentially combustible mixtures of H{sub 2} and O{sub 2}. In addition to identifying the reaction hazards associated with the oxidation of alkali-metal containing complex hydrides, potential treatment methods are identified that chemically stabilize the oxidized material and reduce the hazard associated with handling the contaminated metal hydrides.« less

SL3-111-01516

NASA Image and Video Library

1973-07-01

SL3-111-1516 (July-September 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, uses a battery powered shaver in the crew quarters of the Orbital Workshop (OWS) aboard the Skylab space station cluster in Earth orbit. Astronaut Bean, Owen K. Garriott, science pilot, and Jack R. Lousma, pilot, went on to successfully complete 59 days aboard the Skylab cluster in Earth orbit. Photo credit: NASA

Alteration of Rock Fragments from Columbia River Basalt Microcosms

NASA Technical Reports Server (NTRS)

Wentworth, Susan J.; Thomas-Keprta, Kathie L.; Velbel, Michael A.; McKay, David S.; Stevens, Todd O.

1999-01-01

During an earlier study, microorganisms were grown microcosms consisting of sterilized chips of Columbia River Basalt (CRB) and natural CRB ground water with its natural microflora; environmental conditions simulated a deep subsurface, anaerobic, dark environment. Subsequent scanning and transmission electron microscope (SEM and TEM) studies revealed the presence of several types of bacteria and biofilm, some of which were mineralized. Some of these biological features are very similar to possible biogenic features found in two meteorites from Mars, ALH84001 (found in Antarctica) and Nakhla (observed to fall in Egypt). Both ALH84001 and Nakhla contain traces of low-temperature aqueous alteration of silicates, oxides, and sulfides. The goals of this study are to use high-resolution field-emission SEM (FE-SEM) to examine the CRB samples for evidence of alteration features similar to those in the martian meteorites, to determine the extent of alteration during the CRB microcosm experiments, and to determine whether effects of biological activity can be distinguished from inorganic effects.

Mars Life? - Orange-colored Carbonate Mineral Globules

NASA Technical Reports Server (NTRS)

1996-01-01

This photograph shows orange-colored carbonate mineral globules found in a meteorite, called ALH84001, believed to have once been a part of Mars. These carbonate minerals in the meteorite are believed to have been formed on Mars more than 3.6 billion years ago. Their structure and chemistry suggest that they may have been formed with the assistance of primitive, bacteria-like living organisms. A two-year investigation by a NASA research team found organic molecules, mineral features characteristic of biological activity and possible microscopic fossils inside of carbonate minerals such as these in the meteorite.

Mars Life? - Microscopic Tube-like Structures

NASA Technical Reports Server (NTRS)

1996-01-01

This high-resolution scanning electron microscope image shows an unusual tube-like structural form that is less than 1/100th the width of a human hair in size found in meteorite ALH84001, a meteorite believed to be of Martian origin. Although this structure is not part of the research published in the Aug. 16 issue of the journal Science, it is located in a similar carbonate glob in the meteorite. This structure will be the subject of future investigations that could confirm whether or not it is fossil evidence of primitive life on Mars 3.6 billion years ago.

The Holocaust and History.

ERIC Educational Resources Information Center

Singer, Alan, Ed.

2003-01-01

This theme based journal issue consists of articles and teaching ideas focusing on the Holocaust and history. This publication contains the following materials: (1) "Multiple Perspectives on the Holocaust?" (Alan Singer); (2) "Responses to 'Multiple Perspectives on the Holocaust'"; (3) "Escape to Cuba: Story of Laura Kahn,…

Astronaut Alan Shepard using MET during geological training in Mexico

NASA Technical Reports Server (NTRS)

1970-01-01

Astronaut Alan B. Shepard Jr., commander of the Apollo 14 lunar landing mission, takes a piece of equipment from the Modular Equipment Transporter (MET) during geological and lunar surface simulation training training in the Pinacate volcanic area of northwestern Sonora, Mexico. The MET has been nicknamed 'Rickshaw' after its shape and method of propulsion.

Astronaut Alan Bean holds Special Environmental Sample Container

NASA Technical Reports Server (NTRS)

1969-01-01

Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 lunar landing mission, holds a Special Environmental Sample Container filled with lunar soil collected during the extravehicular activity (EVA) in which Astronauts Charles Conrad Jr., commander, and Bean participated. Connrad, who took this picture, is reflected in the helmet visor of the lunar module pilot.

Astronaut Alan Bean deploys ALSEP during first Apollo 12 EVA on moon

NASA Technical Reports Server (NTRS)

1969-01-01

Astronaut Alan L. Bean, Apollo 12 lunar module pilot, deploys components of the Apollo Lunar Surface Experiments Package (ALSEP) during the first Apollo 12 extravehicular activity (EVA) on the moon. The photo was made by Astronaut Charles Conrad Jr., Apollo 12 commander, using a 70mm handheld Haselblad camera modified for lunar surface usage.

Astronaut Alan Bean steps from ladder of Lunar Module for EVA

NASA Technical Reports Server (NTRS)

1969-01-01

Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 lunar landing mission, steps from the ladder of the Lunar Module to join Astronaut Charles Conrad Jr., commander, in extravehicular activity on November 19, 1969. Astronaut Ricard F. Gordon Jr., command module pilot, remained with the Command/Service Modules in lunar orbit.

Astronaut Alan Bean with subpackages of the ALSEP during EVA

NASA Technical Reports Server (NTRS)

1969-01-01

Astronaut Alan L. Bean, lunar module pilot, traverses with the two subpackages of the Apollo Lunar Surface Experiments Package (ALSEP) during the first Apollo 12 extravehicular activity (EVA). Bean deployed the ALSEP components 300 feet from the Lunar Module (LM). The LM and deployed erectable S-band antenna can be seen in the background.

Tilting at Windmills: School Reform, San Diego, and America?s Race to Renew Public Education

ERIC Educational Resources Information Center

Colvin, Richard Lee

2013-01-01

A book that draws equally on Richard Lee Colvin's deep acquaintance with contemporary education reform and the unique circumstances of the San Diego experience, "Tilting at Windmills" is a penetrating and invaluable account of Alan Bersin's contentious superintendency. Between 1998, when Alan Bersin became superintendent of the San Diego…

The Inevitable War?

DTIC Science & Technology

2011-05-20

69 67 Alan Bryman and Emma Bell , Business Research Methods, 2 ed. (Oxford: Oxford...University Press, USA, 2007), 727. Bryam and Bell define a dependant variable as “ a variable that is causally influenced by another variable.” As the...Pushing-for-Yuan-to-be-Global- Currency-But-Business-Leaders-Say-Not-Yet-114475409.html (accessed April 6, 2011). Bryman , Alan, and Emma Bell

Burning daylight: balancing vitamin D requirements with sensible sun exposure.

PubMed

Stalgis-Bilinski, Kellie L; Boyages, John; Salisbury, Elizabeth L; Dunstan, Colin R; Henderson, Stuart I; Talbot, Peter L

2011-04-04

To examine the feasibility of balancing sunlight exposure to meet vitamin D requirements with sun protection guidelines. We used standard erythemal dose and Ultraviolet Index (UVI) data for 1 June 1996 to 30 December 2005 for seven Australian cities to estimate duration of sun exposure required for fair-skinned individuals to synthesise 1000 IU (25 µg) of vitamin D, with 11% and 17% body exposure, for each season and hour of the day. Periods were classified according to whether the UVI was < 3 or ≥ 3 (when sun protection measures are recommended), and whether required duration of exposure was ≤ 30 min, 31-60 min, or > 60 min. Duration of sunlight exposure required to achieve 1000 IU of vitamin D synthesis. Duration of sunlight exposure required to synthesise 1000 IU of vitamin D varied by time of day, season and city. Although peak UVI periods are typically promoted as between 10 am and 3 pm, UVI was often ≥ 3 before 10 am or after 3 pm. When the UVI was < 3, there were few opportunities to synthesise 1000 IU of vitamin D within 30 min, with either 11% or 17% body exposure. There is a delicate line between balancing the beneficial effects of sunlight exposure while avoiding its damaging effects. Physiological and geographical factors may reduce vitamin D synthesis, and supplementation may be necessary to achieve adequate vitamin D status for individuals at risk of deficiency. ©The Medical Journal of Australia 2011

Facile Synthesis and Superior Catalytic Activity of Nano-TiN@N-C for Hydrogen Storage in NaAlH4.

PubMed

Zhang, Xin; Ren, Zhuanghe; Lu, Yunhao; Yao, Jianhua; Gao, Mingxia; Liu, Yongfeng; Pan, Hongge

2018-05-09

Herein, we synthesize successfully ultrafine TiN nanoparticles (<3 nm in size) embedded in N-doped carbon nanorods (nano-TiN@N-C) by a facile one-step calcination process. The prepared nano-TiN@N-C exhibits superior catalytic activity for hydrogen storage in NaAlH 4 . Adding 7 wt % nano-TiN@N-C induces more than 100 °C reduction in the onset dehydrogenation temperature of NaAlH 4 . Approximately 4.9 wt % H 2 is rapidly released from the 7 wt % nano-TiN@N-C-containing NaAlH 4 at 140 °C within 60 min, and the dehydrogenation product is completely hydrogenated at 100 °C within 15 min under 100 bar of hydrogen, exhibiting significantly improved desorption/absorption kinetics. No capacity loss is observed for the nano-TiN@N-C-containing sample within 25 de-/hydrogenation cycles because nano-TiN functions as an active catalyst instead of a precursor. A severe structural distortion with extended bond lengths and reduced bond strengths for Al-H bonding when the [AlH 4 ] - group adsorbs on the TiN cluster is demonstrated for the first time by density functional theory calculations, which well-explains the reduced de-/hydrogenation temperatures of the nano-TiN@N-C-containing NaAlH 4 . These findings provide new insights into designing and synthesizing high-performance catalysts for hydrogen storage in complex hydrides.

Talking about Israel: 3 Responses

ERIC Educational Resources Information Center

Chronicle of Higher Education, 2006

2006-01-01

Alan Wolfe's article "Free Speech, Israel, and Jewish Illiberalism" prompted numerous responses on The Chronicle's online discussion forum. The essay commented on the debate that erupted following the Polish Consulate's decision to cancel a speech by the scholar Tony Judt--allegedly prompted by protests over his critical views of Israel…

Journal Writing: Pedagogical Perspectives. [SFC Monograph #3.

ERIC Educational Resources Information Center

Casanave, Christine Pearson, Ed.

Articles on the use of student journals in high school and college English-as-a-Second-Language instruction, specifically in the Japanese context, include: "Journal Writing and the Damaged Language Learner" (Alan J. McCormick); "Interested?" (Sven G. M. Puetter); "Tradition and the Student Journal" (George Deaux);…

Cavities shield birds from effects of artificial light at night on sleep.

PubMed

Raap, Thomas; Pinxten, Rianne; Eens, Marcel

2018-05-20

Light pollution is an ever increasing worldwide problem disrupting animal behavior. Artificial light at night (ALAN) has been shown to affect sleep in wild birds. Even cavity-nesting bird species may be affected when sleeping inside their cavity. Correlational studies suggest that light from outside the cavity/nest box, for example from street lights, may affect sleep. We used an experimental design to study to what extent nest boxes shield animals from effects of ALAN on sleep. We recorded individual sleep behavior of free-living great tits (Parus major) that were roosting in dark nest boxes and exposed their nest box entrance to ALAN the following night (1.6 lux white LED light; a similar light intensity as was found at nest boxes near street lights). Their behavior was compared to that of control birds sleeping in dark nest boxes on both nights. Our experimental treatment did not affect sleep behavior. Sleep behavior of birds in the control group did not differ from that of individuals in the light treated group. Our results suggest that during winter cavities shield birds from some effects of ALAN. Furthermore, given that effects of ALAN and exposure to artificial light are species-, sex-, and season-dependent, it is important that studies using wild animals quantify individual exposure to light pollution, and be cautious in the interpretation and generalization of the effects, or lack thereof, from light pollution. Rigorous studies are necessary to examine individual light exposure and its consequences in cavity- and open-nesting birds. © 2018 Wiley Periodicals, Inc.

Editors' overview for the Alan Turner Memorial volume

NASA Astrophysics Data System (ADS)

O'Regan, Hannah J.; Elton, Sarah; Schreve, Danielle

2014-07-01

The papers presented here, in this special volume dedicated to the memory of Alan Turner (1947-2012), provide a glimpse of the multi-faceted ways in which the mammalian fossil record can be investigated. The authors of contributions in this Special Issue are by no means an exhaustive list of his international collaborators and colleagues, and indeed, many are not represented here, but the contents cover many of the topics and issues that were of central archaeological and wider Quaternary mammalian interest to Alan. Although the papers are not intended to provide a comprehensive overview of all techniques that can be applied, the set nevertheless reveals a snapshot of the state-of-the-art and of some of the methods that have the potential to bring much more of the past to life. Alan always sought to move beyond the 'stamp-collecting' approach of simply listing which taxa were present at a site, attempting to elucidate what the presence of those animals might mean in terms of palaeoecology. In particular, the span of Alan's career has seen major advances in our understanding of Quaternary mammalian biostratigraphy and palaeobiogeography, the widespread application of novel techniques such as ancient DNA, the development of high-precision geochronology and the discovery of new hominin species. The papers presented here reflect those developments and highlight interdisciplinary approaches, from examination of sediments to careful measurements of the fossils themselves, from modelling the presence of taxa at particular points in the Quaternary to examination of the similarities and differences in fauna within and between sites.

Search for fullerenes in stone meteorites

NASA Astrophysics Data System (ADS)

Oester, M. Y.; Kuechl, D.; Sipiera, P. P.; Welch, C. J.

1994-07-01

The possibility of identifying fullerenes in stony meteorites became apparent from a paper given by Radicati de Brozolo. In this paper it was reported that fullerenes were present in the debris resulting from a collision between a micrometeoroid and an orbiting satellite. This fact generated sufficient curiosity to initiate a search for the presence of fullerenes in various stone meteorites. In the present study seven ordinary chondrites (al-Ghanim L6 (find), Dimmitt H4 (find), Lazbuddie LL5 (find), New Concord H5 (fall), Silverton H4 (find), Springlake L6 (find), and Umbarger L3/6 (find)). Four carbonaceous chondrites (ALH 83100 C2 (find), ALH 83108 C30 (find), Allende CV3 (fall), and Murchison CM2 (fall), and one achondrite (Monticello How (find)) were analyzed for the presence of fullerenes. The analytical procedure employed was as follows: 100 mg of meteorite was ground up with a mortar and pestle; 10 mL of toluene was then added and the mixture was refluxed for 90 min; this mixture was then filtered through a short column of silica; a 50 microliter sample was then analyzed by high pressure liquid chromatography (HPLC) using a Buckyclutcher I column with a mobile phase consisting of equal volumes of toluene and hexane at a flow rate of 1.00 mg per minute, with detection at 330 and 600 nm. Three of the meteorites, Allende, Murchison, and al-Ghanim, gave HPLC traces containing peaks with similar retention times to the HPLC trace of an authentic fullerene C60. However, further analysis using an HPLC instrument equipped with a diode-array detector failed to confirm any of the substances detected in the three meteorites as C60. Additional analyses will be conducted to identify what the HPLC traces actually represent.

Origins of Magnetite Nanocrystals in Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

Thomas-Keprta, Kathie L.; Clemett, Simon J.; Mckay, David S.; Gibson, Everett K.; Wentworth, Susan J.

2009-01-01

The Martian meteorite ALH84001 preserves evidence of interaction with aqueous fluids while on Mars in the form of microscopic carbonate disks. These carbonate disks are believed to have precipitated 3.9 Ga ago at beginning of the Noachian epoch on Mars during which both the oldest extant Martian surfaces were formed, and perhaps the earliest global oceans. Intimately associated within and throughout these carbonate disks are nanocrystal magnetites (Fe3O4) with unusual chemical and physical properties, whose origins have become the source of considerable debate. One group of hypotheses argues that these magnetites are the product of partial thermal decomposition of the host carbonate. Alternatively, the origins of mag- netite and carbonate may be unrelated; that is, from the perspective of the carbonate the magnetite is allochthonous. For example, the magnetites might have already been present in the aqueous fluids from which the carbonates were believed to have been deposited. We have sought to resolve between these hypotheses through the detailed characterized of the compo- sitional and structural relationships of the carbonate disks and associated magnetites with the orthopyroxene matrix in which they are embedded. Extensive use of focused ion beam milling techniques has been utilized for sample preparation. We then compared our observations with those from experimental thermal decomposition studies of sideritic carbonates under a range of plausible geological heating scenarios. We conclude that the vast majority of the nanocrystal magnetites present in the car- bonate disks could not have formed by any of the currently proposed thermal decomposition scenarios. Instead, we find there is considerable evidence in support of an alternative allochthonous origin for the magnetite unrelated to any shock or thermal processing of the carbonates.

An Interview with Alan J. Hovestadt: AAMFT Past President and Long-Time Marriage and Family Counselor Educator

ERIC Educational Resources Information Center

Juhnke, Gerald A.; Sunich, Michael F.; Coll, Kenneth M.; Lebron-Striker, Maritza

2009-01-01

Alan J. Hovestadt, EdD, is the immediate past president of the 24,000 member American Association for Marriage and Family Therapy (AAMFT) and a long-time IAMFC member who served as an IAMFC founding board member when American Counseling Association (ACA) first granted International Association of Marriage and Family Counselors (IAMFC) divisional…

Astronaut Alan Bean deploys ALSEP during first Apollo 12 EVA on moon

NASA Image and Video Library

1969-11-19

AS12-47-6919 (19 Nov. 1969) --- Astronaut Alan L. Bean, lunar module pilot, deploys components of the Apollo Lunar Surface Experiments Package (ALSEP) during the first Apollo 12 extravehicular activity (EVA) on the moon. The photo was made by astronaut Charles Conrad Jr., commander, using a 70mm handheld Hasselblad camera modified for lunar surface usage.

2016 Summer Series - Alan Stern - The Exploration of Pluto by New Horizons

NASA Image and Video Library

2016-08-11

Interplanetary exploration is essential for the long-term survival of our species. Robotic space exploration allows us to advance our knowledge of our solar system and beyond. Dr. Alan Stern will talk about the New Horizons mission to Pluto and the scientific knowledge gained through the exploration of the icy worlds at the edge of our solar system.

Artificial light at night affects body mass but not oxidative status in free-living nestling songbirds: an experimental study.

PubMed

Raap, Thomas; Casasole, Giulia; Costantini, David; AbdElgawad, Hamada; Asard, Han; Pinxten, Rianne; Eens, Marcel

2016-10-19

Artificial light at night (ALAN), termed light pollution, is an increasingly important anthropogenic environmental pressure on wildlife. Exposure to unnatural lighting environments may have profound effects on animal physiology, particularly during early life. Here, we experimentally investigated for the first time the impact of ALAN on body mass and oxidative status during development, using nestlings of a free-living songbird, the great tit (Parus major), an important model species. Body mass and blood oxidative status were determined at baseline (=13 days after hatching) and again after a two night exposure to ALAN. Because it is very difficult to generalise the oxidative status from one or two measures we relied on a multi-biomarker approach. We determined multiple metrics of both antioxidant defences and oxidative damage: molecular antioxidants GSH, GSSG; antioxidant enzymes GPX, SOD, CAT; total non-enzymatic antioxidant capacity and damage markers protein carbonyls and TBARS. Light exposed nestlings showed no increase in body mass, in contrast to unexposed individuals. None of the metrics of oxidative status were affected. Nonetheless, our study provides experimental field evidence that ALAN may negatively affect free-living nestlings' development and hence may have adverse consequences lasting throughout adulthood.

Artificial light at night affects body mass but not oxidative status in free-living nestling songbirds: an experimental study

PubMed Central

Raap, Thomas; Casasole, Giulia; Costantini, David; AbdElgawad, Hamada; Asard, Han; Pinxten, Rianne; Eens, Marcel

2016-01-01

Artificial light at night (ALAN), termed light pollution, is an increasingly important anthropogenic environmental pressure on wildlife. Exposure to unnatural lighting environments may have profound effects on animal physiology, particularly during early life. Here, we experimentally investigated for the first time the impact of ALAN on body mass and oxidative status during development, using nestlings of a free-living songbird, the great tit (Parus major), an important model species. Body mass and blood oxidative status were determined at baseline (=13 days after hatching) and again after a two night exposure to ALAN. Because it is very difficult to generalise the oxidative status from one or two measures we relied on a multi-biomarker approach. We determined multiple metrics of both antioxidant defences and oxidative damage: molecular antioxidants GSH, GSSG; antioxidant enzymes GPX, SOD, CAT; total non-enzymatic antioxidant capacity and damage markers protein carbonyls and TBARS. Light exposed nestlings showed no increase in body mass, in contrast to unexposed individuals. None of the metrics of oxidative status were affected. Nonetheless, our study provides experimental field evidence that ALAN may negatively affect free-living nestlings’ development and hence may have adverse consequences lasting throughout adulthood. PMID:27759087

The LED outdoor lighting revolution : Opportunities, threats and mitigation

NASA Astrophysics Data System (ADS)

Aube, Martin

2017-01-01

The presence of artificial light at night (ALAN) in environment is now known to have non negligible consequences on the night sky, the fauna, the flora and the human health. A real revolution is undergoing in the outdoor lighting industry threatens the night integrity. This revolution is driven by the advent of the cost-effective Light-Emitting Diode (LED) technology into the outdoor lighting industry. The LEDs provides many opportunities: they are long lasting, easily controlled, and generally allow a more efficient photometric design which, in term, may result in energy savings.After explaining the complex and non-linear behaviour of the propagation of the ALAN into the nocturnal environment, we will outline the potential impact of the ALAN on the human health and on the night sky, and we will introduce some dedicated indicators for its evaluation. We will focus on the role of the blue content of the ALAN in the evaluation of its impact. More specifically we will show how white LED technology, that often shows increased blue light content, compares to the traditional High Pressure Sodium technology. Finally, we will identify the possible mitigations to restrict the adverse impacts of the white LEDs in the urban and rural environment.

Field Emission Gun Scanning Electron (FEGSEM) and Transmission Electron (TEM) Microscopy of Phyllosilicates in Martian Meteorites ALH84001, Nakhla, and Shergotty

NASA Technical Reports Server (NTRS)

Thomas-Keprta, Kathie L.; Wentworth, Susan J.; McKay, David S.; Gibson, Everett K.

2000-01-01

Here we document the occurrence of phyllosilicates and alteration phases in three martian meteorites, suggest formation conditions required for phyllosilicate formation and speculate on the extent of fluid:rock interactions during the past history of Mars.

Mars Life? - Microscopic Tube-like Structures

NASA Image and Video Library

1996-08-09

This high-resolution scanning electron microscope image shows an unusual tube-like structural form that is less than 1/100th the width of a human hair in size found in meteorite ALH84001, a meteorite believed to be of Martian origin. http://photojournal.jpl.nasa.gov/catalog/PIA00288

Evaluation of Meterorite Amono Acid Analysis Data Using Multivariate Techniques

NASA Technical Reports Server (NTRS)

McDonald, G.; Storrie-Lombardi, M.; Nealson, K.

1999-01-01

The amino acid distributions in the Murchison carbonaceous chondrite, Mars meteorite ALH84001, and ice from the Allan Hills region of Antarctica are shown, using a multivariate technique known as Principal Component Analysis (PCA), to be statistically distinct from the average amino acid compostion of 101 terrestrial protein superfamilies.

Photocatalytic effect of green synthesised CuO nanoparticles on selected environmental pollutants and pathogens

NASA Astrophysics Data System (ADS)

Fuku, Xolile; Thovhogi, Ntevheleni; Maaza, Malik

2018-05-01

Highly crystalline irregular green synthesised CuO nanoparticles (CuO NPs) which are 10 nm in particle size were successfully characterised by HRSEM and AFM. EDS confirmed the main components of prepared sample which are Cu and O. Meanwhile, UV/Vis revealed the reflectance, transmittance, absorbance and the semiconducting nature of the synthesised nano-oxides. The optical band gap of CuO NPs was calculated to be 1.4 - 2.3 eV which indicates that CuO NPs can be used in metal oxide semiconductor-based devices. CuO NPs were found to be excellent photocatalysts for the degradation of methyl orange organic dye under the illumination of artificial light irradiation. The experiments demonstrated that MO in aqueous solution was more efficiently photo-degraded (65 %) using CuO NPs as photocatalysts. Further, the nanomaterials were also found to be good inhibitors of bacterial strains at both low and high concentrations of 5 - 10 mg mL-1.

Reversible Dehydration Behavior Reveals Coordinatively Unsaturated Metal Sites in Microporous Aluminum Phosphonates

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

Kinnibrugh, Tiffany L.; Bakhmutov, Vladimir I.; Clearfield, Abraham

2014-10-01

Incorporation of the same ligand into three different aluminum phenylenediphosphonates (Al(H 2O)(O 3PC 6H 4PO 3H) (1), Al-4(H 2O)(2)(O 3PC 6H 4PO 3)(3) (2), and Al-4(H 2O)(4)(O 3PC 6H 4PO 3)(2.84)(OH)(0.64) (3)) was accomplished by varying the synthetic conditions. The compounds have different sorption properties; however, all exhibit reversible dehydration behavior. The structures of the hydrated and dehydrated phases were determined from powder X-ray diffraction data. Compounds 2 and 3 were found to be microporous, while compound 1 was found to be nonporous. The stability of the dehydrated phase and the resulting porosity was found to be influenced by themore » change in the structure upon loss of water.« less

76 FR 66777 - Office of Hazardous Materials Safety; Notice of Application for Special Permits

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-27

... hexafluoride. (modes 1, 2, 3, 4.) 15461-N Kidde Products 49 CFR 171.23... To authorize the High Bentham, Yo..., 3--Cargo vessel, 4--Cargo aircraft only, 5--Passenger-carrying aircraft. DATES: Comments must be... impracticable or not available. (mode 4.) 15469-N B.J. Alan Company 49 CFR 173.62... To authorize the Youngstown...

Bilingual Education. Papers Presented at the Language Teaching Conference (3rd, La Trobe University, May 3-4, 1974).

ERIC Educational Resources Information Center

Rado, Marta, Ed.

The conference was held to alert teachers and other interested persons to the complexities of linguistic diversity in Australia, with attention focused on the immigrant child. This report includes the individual conference papers, presented by Marta Rado, Bert Townsend, Michael Clyne, Alan Matheson, and Rede Lar, and the comments of symposium and…

In vitro and in vivo assessment of newer quinoxaline-oxadiazole hybrids as antimicrobial and antiprotozoal agents.

PubMed

Patel, Navin B; Patel, Jignesh N; Purohit, Amit C; Patel, Vatsal M; Rajani, Dhanji P; Moo-Puc, Rosa; Lopez-Cedillo, Julio Cesar; Nogueda-Torres, Benjamin; Rivera, Gildardo

2017-09-01

A new series of N-(substituted-phenyl)-2-[5-(quinoxalin-2-yloxymethyl)-[1,3,4] oxadiazol-2-ylsulfanyl]-acetamides (5a-o) was designed and synthesised from the parent compound 2-hydroxy quinoxaline (1) through a multistep reaction sequence and was characterised by spectral and elemental analyses. All of the compounds synthesised were evaluated for their antimicrobial and antiprotozoal activities. The results revealed that quinoxaline-based 1,3,4-oxadiazoles displayed promising antibacterial, antifungal and anti-Trypanosoma cruzi activities compared with reference drugs, particularly the lead compound 5l in a short-term in vivo model in T. cruzi. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

ACFER 182/207/214 A Metal-rich, Volatile-poor Chondritic Meteorite, Similar to ALH85085

NASA Astrophysics Data System (ADS)

Palme, H.; Spettel, B.

1992-07-01

The unique Antarctic meteorite ALH85085 was the first chondritic meteorite to contain a significant excess of metallic Fe and associated siderophile elements (e.g., Grossman et al. 1988, Wasson and Kallemeyn 1990). Recently three Sahara meteorites, Acfer 182/207/214, apparently belonging to the same fall, were shown to be chemically and mineralogically very similar to ALHA85085, although minor textural differences appear to exclude a common origin with ALH85085. A mineralogical description and chemical composition of Acfer182/207/214 (henceforth ACFER182) are given in Bischoff et al. (1992). These authors suggested designating ALH85085 and ACFER182 as HH-chondrites reflecting high total Fe and high metal. The Fe/Mg-ratio of ACFER182 is 1.7 times that of CI-chondrites. All metals more refractory than Fe have similar enrichment factors, i.e., non-volatile metals occur in chondritic proportions, except for a slightly lower W enrichment. Metals more volatile than Fe are strongly depleted, with the depletion sequence closely following decreasing condensation temperatures. CI-normalized abundances are: Fe(1.92), Au(1.33), As(1.04), Cu(0.62), Ga(0.38), and the chalcophile Se(0.17). Lithophiles, more refractory than Mg, but including Mg and Cr, also occur in CI-abundance ratios (e.g., Sc/Mg in ACFER182 is 1.05xCI), although their absolute abundances are lower than those of metals. More volatile lithophile elements (Mn, Zn, etc.) decrease in abundance with decreasing condensation temperatures, just as the metals. The parallel (metal and silicate) decrease in moderately volatile element abundances with condensation temperatures suggests a similar nebular history for metal and silicate and is readily understood in a model where nebular gas is continually removed during condensation (Wasson and Chou 1974). Actual mixing of silicate and metal, i.e., agglomeration of silicate and metal grains in non-chondritic proportions (with 70% metal excess) could have occurred at relatively low temperatures, after the chondrule-forming process had transformed silicate grains into chondrules and fine metal grains into coarser metal. Partial loss of volatiles during chondrule formation or reheating of a metal-silicate assemblage with high volatile element abundances are very unlikely to produce the observed depletion sequence as argued by Grossman et al. (1988) for ALH85085. In addition, experiments on artificially heated meteorites produce losses of volatiles that are strongly dependent on fO(sub)2 and are incompatible with the patterns observed in ACFER182 (Wulf and Palme 1991). For example, the observed depletion of Mn in Acfer182 is 0.35 (i.e., 65 % are not condensed). However, Mn loss was never observed in the heating experiments, while large losses of Ga, Se, and Zn were found at temperatures up to 1300 degrees C. At temperatures required for Mn-volatilisation most other moderately volatiles would be quantitatively removed. However, the delicate pattern of moderate volatiles excludes ACFER182 as being a simple mixture of volatile-rich and volatile-poor material. Chemically, ACFER182 and ALHA85085 are related to CR-chondrites. These meteorites follow a trend of increasingly lower contents of volatile elements (e.g., Se, Zn) with decreasing contents of refractory element contents (e.g., Sc), opposite to the major trend in carbonaceous chondrites (from CI to CV). The ACFER182 and ALH85085 meteorites with their low Zn and Se contents and their low Sc abundances appear to form an endmember of this trend. Additional similarities with CR-meteorites in texture, mineralogy, and O, C, and N isotopic compositions (Bischoff et al. 1992; Prinz and Weisberg 1992 and references therein) may indicate that these meteorites are not as unique as originally thought. References: Bischoff A., Palme H., Schultz L., Weber D., Weber H.W. and Spettel B. (submitted to Geochim. Cosmochim. Acta 1992). Grossman J.N., Rubin A.E., MacPherson G.J. (1988) Earth Planet. Sci. Lett. 91, 33-54. Prinz M. and Weisberg M.K. (1992) Lunar. Planet. Sci. (abstract) 23, 1109. Wasson J.T. and Chou C.L. (1974) Meteoritics 9, 69-84. Wasson J.T. and Kallemeyn G.W. (1990) Earth Planet. Sci. Lett. 101, 148-161. Wulf A.-V. and Palme H.(1991) Lunar. Planet. Sci. (abstract) 22, 1527.

Google Moon Press Conference

NASA Image and Video Library

2009-07-19

Alan Eustace, Senior VP of Engineering and Research, Google, Inc., speaks during a press conference, Monday, July 20, 2009, announcing the launch of Moon in Google Earth, an immersive 3D atlas of the Moon, accessible within Google Earth 5.0, Monday, July 20, 2009, at the Newseum in Washington. Photo Credit: (NASA/Bill Ingalls)

Chronicle of Higher Education. Volume 51, Number 3, September 10, 2004

ERIC Educational Resources Information Center

Chronicle of Higher Education, 2004

2004-01-01

"Chronicle of Higher Education" presents an abundant source of news and information for college and university faculty members and administrators. This September 10, 2004 issue of "Chronicle of Higher Education" includes the following articles: (1) "Why America Should Welcome Tariq Ramadan" (Wolfe, Alan; Zimbardo,…

Environment for Learning: The 1970's.

ERIC Educational Resources Information Center

Green, Alan C.

The presentation by Alan C. Green briefly discusses the activities and concerns of EFL and elaborates on the learning environment of the 1970's. Building programming is discussed along with the need to consider--(1) time utilization, (2) architect's early involvement in the process of building programming, (3) prevention of domination over the…

International Handbook of Educational Reform.

ERIC Educational Resources Information Center

Cookson, Peter W., Jr., Ed.; And Others

This book provides an overview of education reform in 27 countries. Following the introduction by Peter W. Cookson, Jr., Alan R. Sadovnik, and Susan F. Semel, part 1 offers national case studies of educational reform in the 1980s. Chapters include: (2) "Argentina" (Ana Munoz-Sandoval); (3) "Australia" (Richard Teese); (4) "Brazil" (Robert Cowen…

The Great Tunes of the Hough: Music and Song in Alan Garner's "The Stone Book Quartet "

ERIC Educational Resources Information Center

Godek, Sarah

2004-01-01

Although song and music are often elements in children's books, little critical attention has gone into examining their literary uses. Alan Garner's "The Stone Book Quartet" is an example of four texts for children in which music plays a vital role. The several snatches of traditional songs found throughout the quartet bring to life the culture of…

Astronaut Alan Bean steps from ladder of Lunar Module for EVA

NASA Image and Video Library

1969-11-19

AS12-46-6729 (19 Nov. 1969) --- Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 lunar landing mission, steps from the ladder of the Lunar Module to join astronaut Charles Conrad Jr., commander, in extravehicular activity on Nov. 19, 1969. Astronaut Richard F. Gordon Jr., command module pilot, remained with the Command and Service Modules in lunar orbit.

Astronaut Alan Bean with subpackages of the ALSEP during EVA

NASA Image and Video Library

1969-11-19

AS12-46-6807 (19 Nov. 1969) --- Astronaut Alan L. Bean, lunar module pilot, traverses with the two sub packages of the Apollo Lunar Surface Experiments Package (ALSEP) during the first Apollo 12 extravehicular activity (EVA). Bean deployed the ALSEP components 300 feet from the Lunar Module (LM). The LM and deployed erectable S-band antenna can be seen in the background.

Counterinsurgency in West Africa: Non Lethal Activities

DTIC Science & Technology

2009-06-01

Michael S. Lewis Beck, Alan Bryman , Tim Futing Liao, The SAGE Encyclopedia of Social Science Research Methods , SAGE, 2004, California, USA.p.894. 11...Publishing, 1966. Michael S. Lewis Beck, Alan Bryman , Tim Futing Liao, The SAGE Encyclopedia of Social Science Research Methods , SAGE, 2004...conduct the research . Research Design The methodology that will be used in this thesis is a qualitative method using case studies. Qualitative research

COMMENTS CONTRIBUTED BY ALAN HUBER TO AWMA AB-3 COMMITTEE FOR POSSIBLE INCLUSION IN THE COMMITTEE'S PRESENTATION AT EPA'S 8TH CONFERENCE ON AIR QUALITY MODELING - A&WMA AB-3 COMMENTS ON NONSTANDARD MODELING APPROACHES

EPA Science Inventory

Technical comments are provided to the Air and waste Management Associations AB-3 committee for potential inclusion into the committee's comments to be made at EPA's 8th Conference on Air Quality Modeling. Computational Fluid Dynamics (CFD) simulations can model specific cases wh...

A Report on Policies and Practices of the U.S. Navy for Naming the Vessels of the Navy

DTIC Science & Technology

2012-11-01

modification was not immediately  evident. The process started when Secretary Gordon R. England named T‐AKE 3  USNS Alan B.  Shepard . The name honored astronaut...and US Navy admiral Alan B.  Shepard , who “Like the legendary explorers, Meriwether Lewis and William Clark,  for whom the first ship of the class was...powered by steam engines. These first cruisers were named in honor of  the cities Atlanta, Boston, and  Chicago . They were followed by 9 ships acquired

The origin of organic matter in the Martian meteorite ALH84001.

PubMed

Becker, L; Popp, B; Rust, T; Bada, J L

1999-01-01

Stable carbon isotope measurements of the organic matter associated with the carbonate globules and the bulk matrix material in the ALH84001 Martian meteorite indicate that two distinct sources are present in the sample. The delta 13C values for the organic matter associated with the carbonate globules averaged -26% and is attributed to terrestrial contamination. In contrast, the delta 13C values for the organic matter associated with the bulk matrix material yielded a value of -15%. The only common carbon sources on the Earth that yield similar delta 13C values, other then some diagenetically altered marine carbonates, are C4 plants. A delta 13C value of -15%, on the other hand, is consistent with a kerogen-like component, the most ubiquitous form of organic matter found in carbonaceous chondrites such as the Murchison meteorite. Examination of the carbonate globules and bulk matrix material using laser desorption mass spectrometry (LDMS) indicates the presence of a high molecular weight organic component which appears to be extraterrestrial in origin, possibly derived from the exogenous delivery of meteoritic or cometary debris to the surface of Mars.

The origin of organic matter in the Martian meteorite ALH84001.

PubMed

Becker, L; Popp, B; Rust, T; Bada, J L

1999-03-30

Stable carbon isotope measurements of the organic matter associated with the carbonate globules and the bulk matrix material in the ALH84001 Martian meteorite indicate that two distinct sources are present in the sample. The delta 13C values for the organic matter associated with the carbonate globules averaged -26% and is attributed to terrestrial contamination. In contrast, the delta 13C values for the organic matter associated with the bulk matrix material yielded a value of -15%. The only common sources of carbon on the Earth that yield similar delta 13C values, other then some diagenetically altered marine carbonates, are C4 plants. A delta 13C value of -15%, on the other hand, is consistent with a kerogen-like component, the most ubiquitous form of organic matter found in carbonaceous chondrites such as the Murchison meteorite. Examination of the carbonate globules and bulk matrix material using laser desorption mass spectrometry (LDMS) indicates the presence of a high molecular weight organic component which appears to be extraterrestrial in origin, possibly derived from the exogenous delivery, of meteoritic or cometary debris to the surface of Mars.

[Shall all lobular intraepithelial neoplasia diagnosed on image-guided biopsy require a surgical management?].

PubMed

Fischer-Hunsinger, Maeva; Guinebretière, Jean-Marc; Lasry, Serge; Langer, Adriana; Berment, Hélène; Nekka, Ibtissem; Nodiot, Philippe; Cherel, Pascal

2016-05-01

Lobular intraepithelial neoplasia (LIN) diagnosed on image-guided biopsy may be associated with an undiagnosed cancer. This is called under-diagnosis. The consequence is that management of these lesions is often surgical. But many surgeries finally are unnecessary. The aim of our study was to define criteria to avoid unnecessary surgery. This is a single-center, retrospective after a database collected prospectively study. Fourteen thousand biopsies were analyzed, including 456 diagnosed NLI. Under-diagnosis rates were analyzed according to many criteria. The average duration of following was 45 months. For atypical lobular hyperplasia (ALH), we obtained 7.6% under-diagnosis and combining several criteria, we got a low risk of cancer (2%). For LCIS, this rate was 23% and any low-risk group could be identified. ALH with calcifications≤20 mm, without any atypical lesion associated, histologically focal and whose removal is representative may be safely observed. For other LIN, surgery remains indicated. Copyright © 2016 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

Information Processing Research.

DTIC Science & Technology

1986-09-01

Kuroe. The 3D MOSAIC Scene Understanding System. In Alan Bundy, Editor, Proceedings of the Eighth International Joint Conference on Artificial ... Artificial Jntelligencel7(1-3):409-460, August, 1981. Given a single picture which is a projection of a three-dimensional scene onto the two...values are detected as outliers by computing the distribution of values over a sliding 80 msec window. During the third pass (based on artificial

Test Review: Kaufman, A. S., & Kaufman, N. L. (2014), "Kaufman Test of Educational Achievement, Third Edition." Bloomington, MN: NCS Pearson

ERIC Educational Resources Information Center

Frame, Laura B.; Vidrine, Stephanie M.; Hinojosa, Ryan

2016-01-01

The Kaufman Test of Educational Achievement, Third Edition (KTEA-3) is a revised and updated comprehensive academic achievement test (Kaufman & Kaufman, 2014). Authored by Drs. Alan and Nadeen Kaufman and published by Pearson, the KTEA-3 remains an individual achievement test normed for individuals of ages 4 through 25 years, or for those in…

SKYLAB (SL)-3 CREW - 1-G TRAINER - MULTIPLE DOCKING ADAPTER (MDA) - JSC

NASA Image and Video Library

1973-06-22

S73-28714 (29 June 1973) --- These three men are the prime crewmen for the Skylab 3 mission. Pictured in the one-G trainer Multiple Docking Adapter (MDA) at the Johnson Space Center (JSC) are, left to right, scientist-astronaut Owen K. Garriott, science pilot; and astronauts Jack R. Lousma and Alan L. Bean, pilot and commander, respectively. Photo credit: NASA

Modeling of Progressive Damage in Fiber-Reinforced Ceramic Matrix Composites

DTIC Science & Technology

1996-03-01

ALAN V. LAIR , Committee Member Professor and Department Head Department of Mathematics and Statistics DAVID D. ROBERTSON, Committee Member Major...other committee members, Prof. Peter Torvik, Prof. Alan Lair , and, representing the dean, Prof. Kirk Mathews for their support and time spent in...34 Journal of Composites Technology and Research, In press (1996). 177. Sorensen B.F. and Talreja R. "Effects of Nonuniformity of Fiber Distribution On

Astronaut Alan Bean assisted with egressing command module after landing

NASA Technical Reports Server (NTRS)

1969-01-01

Astronaut Alan L. Bean, lunar module pilot, is assisted with egressing the Apollo 12 Command Module by a U.S. Navy underwater demolition team swimmer during recovery operations in the Pacific Ocean. Already in the life raft are Astronauts Charles Conrad Jr., commander; and Richard F. Gordon Jr., command module pilot. The Apollo 12 splashdown occured at 2:58 p.m., November 24, 1969 near American Samoa.

Transformation of TNT by Aquatic Plants,

DTIC Science & Technology

1996-01-01

ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Department of Environmental Science and Engineering N/A George R. Brown School of Engineering Rice...Department of Environmental Science and Engineering at Rice University, Dr. Hughes teaches courses in Water and Wastewater Treatment, Biological Process...8:55 Chairperson’s Opening Remarks 1:40 Chairperson’s Remarks Alan J. M. Baker Ph.D., Reader in Environmental Science & Alan J. M. Baker, Ph.D

Photocatalytic activity and reusability of ZnO layer synthesised by electrolysis, hydrogen peroxide and heat treatment.

PubMed

Akhmal Saadon, Syaiful; Sathishkumar, Palanivel; Mohd Yusoff, Abdull Rahim; Hakim Wirzal, Mohd Dzul; Rahmalan, Muhammad Taufiq; Nur, Hadi

2016-08-01

In this study, the zinc oxide (ZnO) layer was synthesised on the surface of Zn plates by three different techniques, i.e. electrolysis, hydrogen peroxide and heat treatment. The synthesised ZnO layers were characterised using scanning electron microscopy, X-ray diffraction, UV-visible diffuse reflectance and photoluminescence spectroscopy. The photocatalytic activity of the ZnO layer was further assessed against methylene blue (MB) degradation under UV irradiation. The photocatalytic degradation of MB was achieved up to 84%, 79% and 65% within 1 h for ZnO layers synthesised by electrolysis, heat and hydrogen peroxide treatment, respectively. The reusability results show that electrolysis and heat-treated ZnO layers have considerable photocatalytic stability. Furthermore, the results confirmed that the photocatalytic efficiency of ZnO was directly associated with the thickness and enlarged surface area of the layer. Finally, this study proved that the ZnO layers synthesised by electrolysis and heat treatment had shown better operational stability and reusability.

Aqueous Alteration of Carbonaceous Chondrites: New Insights from Comparative Studies of Two Unbrecciated CM2 Chondrites, Y 791198 and ALH 81002

NASA Technical Reports Server (NTRS)

Chizmadia, L. J.; Brearley, A. J.

2004-01-01

Carbonaceous chondrites are an important resource for understanding the physical and chemical conditions in the early solar system. In particular, a long-standing question concerns the role of water in the cosmochemical evolution of carbonaceous chondrites. It is well established that extensive hydration of primary nebular phases occurred in the CM and CI chondrites, but the location where this alteration occurred remains controversial. In the CM2 chondrites, hydration formed secondary phases such as serpentine, tochilinite, pentlandite, carbonate and PCP. There are several textural observations which suggest that alteration occurred before the accretion of the final CM parent asteroid, i.e. preaccretionary alteration. Conversely, there is a significant body of evidence that supports parent-body alteration. In order to test these two competing hypotheses further, we studied two CM chondrites, Y-791198 and ALH81002, two meteorites that exhibit widely differing degrees of aqueous alteration. In addition, both meteorites have primary accretionary textures, i.e. experienced minimal asteroidal brecciation. Brecciation significantly complicates the task of unraveling alteration histories, mixing components that have been altered to different degrees from different locations on the same asteroidal parent body. Alteration in Y-791198 is mostly confined to chondrule mesostases, FeNi metal and fine-grained matrix and rims. In comparison, the primary chondrule silicates in ALH81002 have undergone extensive replacement by secondary hydrous phases. This study focuses on compositional and textural relationships between chondrule mesostasis and the associated rim materials. Our hypothesis is: both these components are highly susceptible to aqueous alteration and should be sensitive recorders of the alteration process. For parent body alteration, we expect systematic coupled mineralogical and compositional changes in rims and altered mesostasis, as elemental exchange between these components occurs. Conversely, for preaccretionary alteration, there should be no clear relationships between the rims and mesostases.

Training for New Trends in Clubs and Centers for Older Persons.

ERIC Educational Resources Information Center

New York State Education Dept., Albany. Bureau of Special Continuing Education.

The proceedings of an inservice leadership training seminar for enriching the education-recreation programs for the elderly in New York State are presented. The following speeches were given: (1) "The Anatomy of Leadership" by Alan F. Klein; (2) "Leadership for What?" by Marvin S. Schreiber; (3) "Operationalizing Your Leadership With Groups" by…

Seminar Series for School Administrators. Volume 1, Leadership.

ERIC Educational Resources Information Center

Carson, Robert B., Ed.

A collection of six papers presented on separate occasions to practicing administrators deals with the need for better leadership in administration. The authors and titles of the papers are (1) R. B. Howsam, "Administering Tomorrow's Schools," (2) H. W. Kitchen, "Recent Studies Relating to Leadership," (3) Alan F. Brown, "Reactions to Leadership,"…

Press Conference - Skylab 3

NASA Image and Video Library

1972-08-14

S72-46699 (19 Jan. 1972) --- Prime crew members of the scheduled second Skylab mission are introduced to the media during a press conference in January 1972 at the Manned Spacecraft Center (MSC). From left to right are astronauts Jack R. Lousma, pilot; Owen K. Garriott, science pilot, and Alan L. Bean, commander. Photo credit: NASA

The Learning Revolution: Education Innovations for Global Citizens.

ERIC Educational Resources Information Center

Gilman, Robert, Ed.

1991-01-01

This theme journal issue is devoted to the learning revolution in educational innovations aimed at global citizens. The article titles and authors are as follows: (1) "A Personal Introduction" by Alan AtKisson; (2) "Onward and Upward!" by Dee Dickinson; (3) "Multiple Intelligences in the Classroom" by Bruce Campbell; (4) "Learning As…

Consensus report on the future of animal-free systemic toxicity testing

EPA Science Inventory

This is a multi-authored consensus report from conferences held in 2011-2012. Complete author listing is as follows: Marcel Leist1,2, Nina Hasiwa1, Costanza Rovida1, Mardas Daneshian1, David Basketter3, Ian Kimber4, Harvey Clewell5, Tilman Gocht6, Alan Goldberg7, Derek Knight8, G...

The Hues of English. NCTE Distinguished Lectures 1969.

ERIC Educational Resources Information Center

National Council of Teachers of English, Champaign, IL.

The third volume in the NCTE Distinguished Lectures Series, this collection of papers includes (1) William Stafford on poetry and the language of everyday life, (2) Fred Stocking linking Shakespeare to his time and all time by analysing "temperance" in Sonnet 18, (3) Alan Downer discussing the nature of comedy in drama and the universal…

Getting to the guts of enteric nervous system development.

PubMed

Heuckeroth, Robert O; Pachnis, Vassilis

2006-06-01

Scientists from around the world gathered in New York City recently to discuss the latest research on enteric nervous system development at a meeting organised by Alan Burns and Heather Young. The participants enjoyed 3 days of presentations that spurred active conversations and highlighted the rapidly advancing research in this field.

Report on Component 2 - Designing New Methods for Visualizing Text in Spatial Contexts

DTIC Science & Technology

2012-10-31

W9132V-11-P-0010 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Alexander Savelyev , Scott Pezanowski, Anthony C. Robinson, and Alan M...e Component 2 – Designing New Methods for Visualizing Text in Spatial Contexts Alexander Savelyev , Scott Pezanowski, Anthony Robinson and Alan...Center, Penn State University Report on Component 2: Component 2 – Designing New Methods for Visualizing Text in Spatial Contexts Alexander

Results of SEI Independent Research and Development Projects and Report on Emerging Technologies and Technology Trends

DTIC Science & Technology

2005-12-01

W. Collins Peter Feiler John Goodenough Aaron Greenhouse Jorgen Hansson Alan R . Hevner John Hudak Angel Jordan Rick Kazman Richard C. Linger...John Goodenough Aaron Greenhouse Jorgen Hansson Alan R . Hevner John Hudak Angel Jordan Rick Kazman Richard C. Linger Mark G. Pleszkoch Stacy J...operability, sustainability, software R &D, metrics for acquisition, acquisition management, and commercial off-the-shelf products. The IR&D projects conducted

Precision Minds: An Investigation Into the use of Information in Operational-Level Decision Making and Learning

DTIC Science & Technology

2005-06-17

Procedures and Techniques. (California: Thousand Oaks 1998),11. 14 Alan Bryman Quantity and Quality in Social Research . (London: Unwin, 1988), 8. 48... Bryman , Alan. Quantity and Quality in Social Research . London: Unwin, 1988. Clark, Wesley. Winning Modern Wars: Iraq, Terrorism, and the American...a global audience than ever before. Under such conditions the practical business of defeating the enemy militarily in such a way as to deliver

Destabilized and catalyzed borohydride for reversible hydrogen storage

DOEpatents

Mohtadi, Rana F [Northville, MI; Zidan, Ragaiy [Aiken, SC; Gray, Joshua [Aiken, SC; Stowe, Ashley C [Knoxville, TN; Sivasubramanian, Premkumar [Aiken, SC

2012-02-28

A process of forming a hydrogen storage material, including the steps of: providing a borohydride material of the formula: M(BH.sub.4).sub.x where M is an alkali metal or an alkaline earth metal and 1.ltoreq.x.ltoreq.2; providing an alanate material of the formula: M.sub.1(AlH.sub.4).sub.x where M.sub.1 is an alkali metal or an alkaline earth metal and 1.ltoreq.x.ltoreq.2; providing a halide material of the formula: M.sub.2Hal.sub.x where M.sub.2 is an alkali metal, an alkaline earth metal or transition metal and Hal is a halide and 1.ltoreq.x.ltoreq.4; combining the borohydride, alanate and halide materials such that 5 to 50 molar percent from the borohydride material is present forming a reaction product material having a lower hydrogen release temperature than the alanate material.

From Mercury to Apollo: astronaut Alan Shepard reflects on life support and other space issues [interview by Winston Huff].

PubMed

Shepard, A

1995-01-01

Alan Shepard was one of the original Mercury astronauts. He became the first American in space on May 5, 1961, in the Freedom 7 capsule, during a 15 minute suborbital trip reaching 115 miles altitude and 302 miles down the Atlantic tracking range. Grounded by an inner ear problem, he served as Chief of the Astronaut Office for several years. After an operation to correct the problem, he commanded the Apollo 14 moon mission in 1971. He retired as a Rear Admiral in 1974. Here, Alan Shepard offers his views on life support comedies and tragedies, going back to the moon, future drivers of the manned space flight program, the benefits of the space program, joint NASA and Russia missions, how his NASA experience affected his personal life, and the profitability of working with NASA.

U.S. EPA, Pesticide Product Label, MYCOTROL ES, 11/13/2008

EPA Pesticide Factsheets

2011-04-21

... rL"plr~iI,'r Ille·l·tillg .\\iII)SI I sl~llldards nfa( kast R-'):'i or Pl)5. Rq)~alCd L'XpOSUI\\' III hit!h l'PllcL'llIr:lliull:' pI" 1l1l .... Ttihl:!I 111"1)IL'II1:-. (:llll';ltl:-'l' alh . ...

The CaGeO3 Ca3Fe2Ge3O12 garnet join: an experimental study

NASA Astrophysics Data System (ADS)

Iezzi, Gianluca; Boffa-Ballaran, Tiziana; McCammon, Catherine; Langenhorst, Falko

2005-06-01

Germanate garnets are often used as isostructural analogues of silicate garnets to provide insight into the crystal chemistry and symmetry of the less accessible natural garnet solid solutions. We synthesised two series of germanate garnets at 3 GPa along the joinVIIICa3VI(CaGe)IVGe3O12 VIIICa3VIFe2IVGe3O12 at 900 °C and 1,100 °C. Samples with compositions close to the CaGeO3 end-member consist of tetragonal garnet with a small amount of triclinic CaGe2O5. Samples with nominal compositions between XFe=0.4 and 1.0 consist of a mixture of tetragonal and cubic garnets; whereas, single-phase cubic garnets were obtained for compositions with XFe>1.2 (XFe gives the iron content expressed in atoms per formula unit, and varies between 0 and 2 along the join). Run products which were primarily single-phase garnet were investigated using Mössbauer spectroscopy. Spectra from samples synthesised at 1,100°C consist of one well-resolved doublet that can be assigned to Fe3+ in the octahedral site of the garnet structure. A second doublet, present primarily in samples synthesised at 900°C, can be assigned to Fe2+ at the octahedral sites of the garnet structure. The relative abundance of Fe2+ decreases with increasing iron content. Transmission electron microscopy analyses confirm this tendency and show that the garnets are essentially defect-free. The unit-cell parameters of tetragonal VIIICa3VI(CaGe)IVGe3O3 garnet decrease with increasing synthesis temperature, and the deviation from cubic symmetry becomes smaller. Cubic garnets show a linear decrease of unit-cell parameter with increasing iron content. The results are discussed in the context of iron incorporation into VIIIMg3VI(MgSi)IVSi3O3 majorite.

FTIR Analysis of Water in Pyroxene and Plagioclase in ALH 84001 and Nakhlites

NASA Technical Reports Server (NTRS)

Peslier, A. H.; Cintala, M. J.; Montes, R.; Cardenas, F.

2016-01-01

Determining the volatile budget of the interior of Mars is crucial for our understanding of that planet's formation, geodynamics, cooling history and the origin of its volcanism and atmosphere as well as its potential for life. Surficial water is evident from spacecraft and rover data in polar caps and the atmosphere, in the presence of river channels, and in the detection of water-bearing minerals. Meteorites, however, are our best candidates for estimating the amount of water present at depth, even if all are crustal samples. The last 10 years have seen a blooming of studies measuring water and halogens in Martian meteorites. The bulk of these studies target phosphate, a typically late-stage phase in the igneous Martian meteorites that potentially would concentrate incompatible element hydrogen (H quantified traditionally as "water", i.e., H2O concentrations in weight) near the end of the crystallization sequence. However, determining the amount of water, F, and Cl in the magma from which a phosphate crystallized from is not straightforward and in most instances not possible. On the other hand, phosphates have turned out to be very useful in identifying hydrothermal processes that could have added water while or after the magma flowed and crystallized. Another caveat of analyzing Martian meteorite phases for water is that shocked phases such as maskelynite and impact melts appear to have incorporated water from the Martian atmosphere, as evidenced by high H isotope ((delta)D) signatures, and therefore their water concentrations cannot be interpreted in terms of deep planetary processes. The best candidates for estimating the water content of the Martian interior have been melt inclusions (glass or amphibole-bearing) which the enclosing mineral (usually olivine) would have prevented from exchanging volatiles with the surroundings after crystallization. Even some of these, however, have high (delta)D, meaning they were affected by H exchange via impact events or with crustal reservoirs or hydrothermal fluids. Here, nominally anhydrous minerals (pyroxene, olivine, plagioclase, or maskelynite) in orthopyroxenite ALH 84001 and selected nakhlites are analyzed for water and major elements, in order to determine 1) whether they contain any water; 2) if they do, what controls its distribution (crystallization, degassing, hydrothermal or impact processes); and 3) if any of these measurements can be used to infer the water contents of the parent magma and their mantle sources. A shock-reverberation experiment was also performed on terrestrial orthopyroxenes (opx) to simulate the heavily shocked conditions of ALH 84001 (> 31 GPa [17]).

ASTRONAUT LOUSMA, JACK - EGRESS - SKYLAB 3 COMMAND MODULE - PACIFIC

NASA Image and Video Library

1973-09-25

S73-36435 (25 Sept. 1973) --- Astronaut Jack R. Lousma, Skylab 3 pilot, egresses the Skylab 3 Command Module aboard the prime recovery ship, USS New Orleans, during recovery operations in the Pacific Ocean. Astronauts Lousma; Alan L. Bean, commander; and Owen L. Garriott, science pilot, had just completed a successful 59-day visit to the Skylab space station in Earth orbit. The Skylab 3 spacecraft splashed down in the Pacific about 230 miles southwest of San Diego, California. Photo credit: NASA

Skylab 3,Astronaut Jack R. Lousma on EVA

NASA Image and Video Library

1973-08-06

SL3-122-2612 (6 Aug. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, participates in the final Skylab 3 extravehicular activity (EVA), during which a variety of tasks were performed. Here, Bean is near the Apollo Telescope Mount (ATM) during final film change out for the giant telescope facility. Astronaut Owen K. Garriott, who took the picture, is reflected in Bean's helmet visor. The reflected Earth disk in Bean's visor is so clear that the Red Sea and Nile River area can delineated. Photo credit: NASA

Green synthesis of silver nanoparticles using flower extract of Malva sylvestris and investigation of their antibacterial activity.

PubMed

Mahmoodi Esfanddarani, Hassan; Abbasi Kajani, Abolghasem; Bordbar, Abdol-Khalegh

2018-06-01

High-quality colloidal silver nanoparticles (AgNP) were synthesised via a green approach by using hydroalcoholic extracts of Malva sylvestris . Silver nitrate was used as a substrate ion while the plant extract successfully played the role of reducing and stabilising agents. The synthesised nanoparticles were carefully characterised by using transmission electron microscopy, atomic-force microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and UV-vis spectroscopy. The maximum absorption wavelengths of the colloidal solutions synthesised using 70 and 96% ethanol and 100% methanol, as extraction solvents, were 430, 485 and 504 nm, respectively. Interestingly, the size distribution of nanoparticles depended on the used solvent. The best particle size distribution belonged to the nanoparticles synthesised by 70% ethanol extract, which was 20-40 nm. The antibacterial activity of the synthesised nanoparticles was studied on Escherichia coli , Staphylococcus aureus and Streptococcus pyogenes using disk diffusion, minimum inhibitory concentrations and minimum bactericidal concentrations assays. The best antibacterial activity obtained for the AgNPs produced by using 96% ethanolic extract.

Photocatalytic, antioxidant, antibacterial and anti-inflammatory activity of silver nanoparticles synthesised using forest and edible mushroom

NASA Astrophysics Data System (ADS)

Sriramulu, Mohana; Sumathi, Shanmugam

2017-12-01

Mushroom has been part of the human diet for thousands of years, and in recent times, the amounts consumed have risen greatly, involving a large number of species. Mushrooms used for nutritional and therapeutic purposes. In this study silver nanoparticles were synthesised using an edible mushroom (Agaricus bisporus) and forest mushroom (Ganoderma lucidum) extract. The synthesised nanoparticles were characterised by UV-vis spectroscopy, FTIR, powder XRD and SEM. Silver nanoparticles were synthesised at room temperature and at 60 °C. FTIR results recognised the presence of bioactive functional groups responsible for the reduction of silver nitrate to silver nanoparticles. From the XRD, it was observed that the nanoparticles are silver with an average size of 10-80 nm. The silver nanoparticles are explored for photocatalytic activity and biological activities such as in vitro antioxidant activity, anti-inflammatory activity and antimicrobial activity against Escherichia coli and Staphylococcus aureus organisms. 98% of textile dye (direct blue 71) degradation was noticed under UV light within 150 min for forest mushroom synthesised silver nanoparticles at room temperature.

Lidar - ESRL WindCube 200s, Wasco Airport - Derived Data

DOE Data Explorer

Choukulkar, Aditya

2017-10-23

The available "readme" file introduces the basics of the Doppler lidar data and offers a detailed description of the variables present in the data files. If you have any further questions about the data and its interpretation, contact either Alan Brewer () or Aditya Choukulkar (). It is highly recommended to discuss any planned use of the data with NOAA-CSD scientists. For more information, refer to the attached readme.

ASTRONAUT BEAN, ALAN L - SIMULATION - BLDG. 35 - COMMAND MODULE TRAINER - JSC

NASA Image and Video Library

1975-02-20

S75-21720 (14 Feb. 1975) --- Astronaut Alan L. Bean (foreground) and cosmonaut Aleksey A. Leonov participate in Apollo-Soyuz Test Project joint crew training in Building 35 at NASA's Johnson Space Center. They are in the Apollo Command Module trainer. The training session simulated activities on the first day in Earth orbit. Bean is the commander of the American ASTP backup crew. Leonov is the commander of the Soviet ASTP first (prime) crew.

Regionally Aligned Forces: The Critical Role of Military Engagement and Interdependence Between Conventional and Special Operations Forces

DTIC Science & Technology

2015-05-21

110 Ibid., 212. 111 Ibid., 43-45. 112 Peter L. Berger and Thomas Luckmann, The Social Construction of...time and resources. As noted by Army Colonel Alan Shumate, a former battalion commander in a unit similar to 2/1 ABCT, “I personally experienced how...136 Alan Shumate, “Employing US Army Special Forces to Defeat America’s Emerging Threats,” manuscript USAWC Civilian Research Project, US

Electrochemical and Photochemical Treatment of Aqueous Waste Streams

DTIC Science & Technology

1996-01-01

TREATMENT OF AQUEOUS WASTE STREAMS Joseph C. Farmer, Richard W. Pekala, Francis T. Wang, David V. Fix, Alan M. Volpe, Daniel D. Dietrich, William H...STREAMS Joseph C. Farmer, Richard W. Pekala, Francis T. Wang, David V. Fix, Alan M. Volpe, Daniel D. Dietrich, William H. Siegel and James F. Carley...1992). Wilbourne , C. M. Wong, , W. S. Gillam, S. Johnson, R. H. Horowitz, "Electrosorb Process for Desalting Water," Res. Dev. Prog. Rept. No. 516, 16. J

Predicate Abstraction of ANSI-C Programs using SAT

DTIC Science & Technology

2003-09-23

compositionally and automatically. In Alan J. Hu and Moshe Y. Vardi, editors, Computer-Aided Verification, CAV ’98, volume 1427, pages 319–331, Vancouver...Languages, POPL ’77, pages 238–252, 1977. [14] David W. Currie, Alan J. Hu, Sreeranga Rajan, and Masahira Fujita. Automatic formal verification of dsp...Languages and Systems (TOPLAS), 2(4):564–79, 1980. [19] A. Gupta, Z. Yang, P. Ashar , and A. Gupta. SAT-based image computation with application in

Astronaut Bean - Acrobatics - Orbital Workshop (OWS)

NASA Image and Video Library

1973-08-20

S73-32632 (19 Aug. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, performs acrobatics and simulated gymnastics in the dome area of the Orbital Workshop in this photographic reproduction taken from a television transmission made by a color TV camera aboard the Skylab space station in Earth orbit. Bean appears to be floating in a diving position. Photo credit: NASA

Realizing the Potential of Information Resources: Information, Technology, and Services. Track 3: Serving Clients with Client/Server.

ERIC Educational Resources Information Center

CAUSE, Boulder, CO.

Eight papers are presented from the 1995 CAUSE conference track on client/server issues faced by managers of information technology at colleges and universities. The papers include: (1) "The Realities of Client/Server Development and Implementation" (Mary Ann Carr and Alan Hartwig), which examines Carnegie Mellon University's transition…

Assessment Update: Progress, Trends, and Practices in Higher Education. Volume 29, Issue 5, September-October 2017

ERIC Educational Resources Information Center

Hundley, Stephen P., Ed.

2017-01-01

This issue of "Assessment Update" presents the following articles: (1) Using National Benchmarking Data to Improve Student Learning in Chemistry at Lebanon Valley College (Marc A. Harris); (2) Mutually Dependent Outcomes: Using Assessment to Improve First-Year Retention and Student Learning (Alan Bearman and Elaine Lewis); (3) Emergent…

78 FR 46903 - Control Date for Qualifying Landings History and to Limit Speculative Entry into the Illex Squid...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-02

.... Dated: July 30, 2013. Alan D. Risenhoover, Director, Office of Sustainable Fisheries, performing the... Council considers if and how access to the Illex squid fishery should be controlled. DATES: August 2, 2013... before September 3, 2013. ADDRESSES: You may submit comments on this document, identified by NOAA-NMFS...

Non-ionic block copolymers leading to a highly ordered organosilica material

NASA Astrophysics Data System (ADS)

Rebbin, V.; Rothkirch, A.; Vainio, U.; Funari, S. S.

2012-03-01

Phenylene-bridged periodic mesoporous organosilica (PMO) materials with hexaethylene glycol mono hexadecylether (C16(EO)6) as structure directing agent (SDA) in acidic solution were synthesised and the reaction was studied in different conditions, including in situ small angle X-ray scattering at room temperature and at 60 °C. The in situ SAXS investigations at 60 °C show the formation of a 2D hexagonal mesostructure after 3 hours reaction time. In contrast to these results the same reaction performed in the laboratory produced a powder that, after drying at room temperature, shows a large number of diffraction peaks, allowing identifying a lamellar structure, possibly in coexistence of a micellar cubic structure (space group Pm3n). Aposteriori removal of the surfactant from the powder synthesised in the laboratory led to the collapse of the lamellar structure.

Ameliorative effects of amide derivatives of 1,3,4-thiadiazoles on scopolamine induced cognitive dysfunction.

PubMed

Kulshreshtha, Akanksha; Piplani, Poonam

2016-10-21

The present study reports the effect of amide derivatives of 1,3,4-thiadizoles on scopolamine induced deficit cholinergic neurotransmission and oxidative stress serving as promising leads for the therapeutics of cognitive dysfunction. Fourteen compounds (2c-8d) have been synthesised and evaluated against behavioural alterations using step down passive avoidance protocol and morris water maze and at a dose of 0.5 mg/kg with reference to the standard, Rivastigmine. All the synthesised compounds were evaluated for their in vitro acetylcholinesterase (AChE) inhibition at five different concentrations using mice brain homogenate as the source of the enzyme. Biochemical estimation of markers of oxidative stress (lipid peroxidation, superoxide dismutase, glutathione, plasma nitrite, catalase) has also been carried out to assess the role of synthesised molecules on the oxidative damage induced by scopolamine. The compounds 5c, 6c and 8c displayed appreciable activity with an IC50 value of 3 μM, 3.033 μM and 2.743 μM, respectively towards acetylcholinesterase inhibition. These compounds also decreased scopolamine induced oxidative stress, thus serving as promising leads for the amelioration of oxidative stress induced cognitive decline. The molecular docking study performed to predict the binding mode of the compounds also suggested that these compounds bind appreciably with the amino acids present in the active site of recombinant human acetylcholinesterase (rhAChE). The results indicated that these compounds could be further traversed as inhibitors of AChE and oxidative stress for the treatment of cognitive dysfunction. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Population-level study links short-wavelength nighttime illumination with breast cancer incidence in a major metropolitan area.

PubMed

Rybnikova, Nataliya; Portnov, Boris A

2018-05-16

Several population-level studies revealed a positive association between breast cancer (BC) incidence and artificial light at night (ALAN) exposure. However, the effect of short-wavelength illumination, implicated by laboratory research and small-scale cohort studies as the main driving force behind BC-ALAN association, has not been supported by any population-level study carried out to date. We investigated a possible link between BC and ALAN of different subspectra using a multi-spectral year-2011 satellite image, taken from the International Space Station, and superimposing it with year-2013 BC incidence data available for the Great Haifa Metropolitan Area in Israel. The analysis was performed using both ordinary least square (OLS) and spatial dependency models, controlling for socioeconomic and locational attributes of the study area. The study revealed strong associations between BC and blue and green light subspectra (B = 0.336 ± 0.001 and B = 0.335 ± 0.002, respectively; p < 0.01), compared to a somewhat weaker effect for the red subspectrum (B = 0.056 ± 0.001; p < 0.01). However, spatial dependency models, controlling for spatial autocorrelation of regression residuals, confirmed only a positive association between BC incidence and short-wavelength (blue) ALAN subspectrum (z = 2.462, p < 0.05) while reporting insignificant associations between BC and either green (z = 1.425, p > 0.1) or red (z = -0.604, p > 0.1) subspectra. The obtained result is in line with the results of laboratory- and small-scale cohort studies linking short-wavelength nighttime illumination with circadian disruption and melatonin suppression. The detected effect of blue lights on BC incidence may help to develop informed illumination policies aimed at minimizing the adverse health effects of ALAN exposure on human health.

Skylab 3 crewmen shown eating in Orbital Workshop wardroom

NASA Technical Reports Server (NTRS)

1973-01-01

The three Skylab 3 crewmen are shown eating in the Orbital Workshop (OWS) wardroom of the Skylab space station in Earth orbit, in this photographic reproduction taken from a television transmission made by a color TV camera aboard the OWS. Astronaut Alan L. Bean (right), commander, illustrates eating under zero gravity conditions upsidedown. The two other crewmen are Scientist-Astronaut Owen K. Garriott (left), science pilot; and Astronaut Jack R. Lousma, pilot.

Decision Factors for Cooperative Multiple Warhead UAV Target Classification and Attack with Control Applications

DTIC Science & Technology

2004-10-01

Jeffrey P. Kharoufeh Committee Member Date /signed/ 22 Oct 04 Dr. Alan V. Lair Dean’s Representative Date /signed/ Robert A. Calico, Jr Dean...who also provided great comments on my drafts. As far as the drafts go, thanks to all the committee and the Dean’s Representative (Dr. Alan Lair ) for...11. Cozzolino, J.M. “Sequential Search for an Unknown Number of Objects of Nonuniform Size,” Operations Research, 20 :293–308 (1972). 12. de Guenin

Isolation of a Toxin from Venom of Wagler’s Pit Viper Trimeresurus wagleri

DTIC Science & Technology

1990-01-31

AUTHOR(S) Scott A. Weinstein, Alan W. Bernheimer and Leonard A. Smith 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year, Month, Day) 15. PAGE...WAGLERI SCOTT A. WEINSTEIN, 1 ALAN W. BERNHEIMER , 2 AND LEONARD A. SMITH1 * 1 Department of Toxinology, Pathology Division, United States Army Medical...Weinstein, A. W. Bernheimer , and L. A. Smith. Isolation of a toxin from venom of Waglers pit viper Trimeresurus wagleri. Toxicon .,- ,19--. A lethal

Astronaut Alan Bean works on Modular Equipment Stowage Assembly

NASA Image and Video Library

1969-11-19

AS12-46-6749 (19 Nov. 1969) --- Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 lunar landing mission, works at the Modular Equipment Stowage Assembly (MESA) on the Apollo 12 Lunar Module (LM) during the mission's first extravehicular activity, (EVA) on Nov. 19, 1969. Astronaut Charles Conrad Jr., commander, and Bean descended in the Apollo 12 LM to explore the moon while astronaut Richard F. Gordon Jr., command module pilot, remained with the Command and Service Modules (CSM) in lunar orbit.

Apollo 12 Mission image - Dark view of Astronaut Alan L. Bean climbing down the ladder of the Lunar Module (LM)

NASA Image and Video Library

1969-11-19

AS12-46-6728 (19 Nov. 1969) --- Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 mission, is about to step off the ladder of the Lunar Module to join astronaut Charles Conrad Jr., mission commander, in extravehicular activity (EVA). Conrad and Bean descended in the Apollo 12 LM to explore the moon while astronaut Richard F. Gordon Jr., command module pilot, remained with the Command and Service Modules in lunar orbit.

The U.S. Navy in Operation Overlord Under the Command of Rear Admiral Alan G. Kirk

DTIC Science & Technology

1994-05-19

assault on the beaches. 14. SUBJECT TERMS 15. NUMBER OF PAGES Operation Overlord, COSSAC, Admiral Alan G. Kirk, U.S. Navy 16. PRICE CODE 17. SECUriLY ...Allies’ smal2 but growing forces. 5 Although reluctant to confront the German Army in France, Brooke admitted that reasons existed to take the Qamble; the...After Kirk took command of TF122, the pace of American landing craft and personnel arrival into Britain rapidly increased. Kirk told Stark that the

Strength and Microstructure of Ceramics

DTIC Science & Technology

1989-11-01

processing defects (pores or inclusions), etc. Theoretically, flaws have been represented as scaled-down versions of large cracks, so that the...no spurious reflections. confirming that the defects were not microtwins, From the TEM evidence. alhing with corresponding observations of fault...Lawn Vol. 71. No. I Interfaces. can be viewred as high-energy planar defects . AS Such. V. Conclusions they represent favored sites for microcrack

Fine-Grained Rims in the Allan Hills 81002 and Lewis Cliff 90500 CM2 Meteorites: Their Origin and Modification

NASA Technical Reports Server (NTRS)

Hua, X.; Wang, J.; Buseck, P. R.

2002-01-01

Antarctic CM meteorites Allan Hills (ALH) 8 1002 and Lewis Cliff (LEW) 90500 contain abundant fine-grained rims (FGRs) that surround a variety of coarse-grained objects. FGRs from both meteorites have similar compositions and petrographic features, independent of their enclosed objects. The FGRs are chemically homogeneous at the 10 m scale for major and minor elements and at the 25 m scale for trace elements. They display accretionary features and contain large amounts of volatiles, presumably water. They are depleted in Ca, Mn, and S but enriched in P. All FGRs show a slightly fractionated rare earth element (REE) pattern, with enrichments of Gd and Yb and depletion of Er. Gd is twice as abundant as Er. Our results indicate that those FGRs are not genetically related to their enclosed cores. They were sampled from a reservoir of homogeneously mixed dust, prior to accretion to their parent body. The rim materials subsequently experienced aqueous alteration under identical conditions. Based on their mineral, textural, and especially chemical similarities, we conclude that ALH 8 1002 and LEW 90500 likely have a similar or identical source.

Trace element distributions in primitive achondrites

NASA Technical Reports Server (NTRS)

Davis, Andrew M.; Prinz, Martin; Weisberg, Michael K.

1993-01-01

The primitive achondrites have approximately chondritic bulk chemical composition but achondritic textures. Clayton et al. show that nine of these meteorites, the acapulcoites and the lodranites, have similar oxygen isotopic compositions. The acapulcoites appear to be highly metamorphosed, but undifferentiated meteorites of chondritic composition; whereas, the lodranites appear to have lost a feldspathic partial melt. In order to learn more about metamorphic processes and partial melt removal, we have measured the trace element compositions of constituent phases of a number of primitive achondrites by ion microprobe. We have analyzed two acapulcoites, Acapulco and ALH81261 (paired with ALH77081), and three londranites, Lodran, LEW88280, and MAC88177. In addition, we analyzed LEW88663, which has the bulk composition, mineral chemistry, and oxygen isotopic composition of L-chondrites, but is metal-free and has an achondrite texture; and Divnoe, a plagioclase-poor, olivine-rich primitive achondrite with an oxygen isotopic composition similar to that of the group IAB iron meteorites. These meteorites show a variety of REE patterns in their constituent phases, and there are consistent differences between acapulcoites and lodranites that are consistent with removal of a LREE- and Eu-enriched melt that is apparently responsible for the low plagioclase content of lodranites.

High Resolution Chemical Study of ALH84001

NASA Technical Reports Server (NTRS)

Conrad, Pamela G.; Douglas, Susanne; Kuhlman, Kimberly R.

2001-01-01

We have studied the chemistry of a sample of the SNC meteorite ALH84001 using an environmental scanning electron microscope (ESEM) with an energy dispersive chemical analytical detector and a focused ion beam secondary ion mass spectrometer (FIB-SIMS). Here we present the chemical data, both spectra and images, from two techniques that do not require sample preparation with a conductive coating, thus eliminating the possibility of preparation-induced textural artifacts. The FIB-SIMS instrument includes a column optimized for SEM with a quadrupole type mass spectrometer. Its spatial and spectral resolution are 20 nm and 0.4 AMU, respectively. The spatial resolution of the ESEM for chemical analysis is about 100 nm. Limits of detection for both instruments are mass dependent. Both the ESEM and the FIB-SIMS instrument revealed contrasting surficial features; crumbled, weathered appearance of the matrix in some regions as well as a rather ubiquitous presence of euhedral halite crystals, often associated with cracks or holes in the surface of the rock. Other halogen elements present in the vicinity of the NaCl crystals include K and Br. In this report, elemental inventories are shown as mass spectra and as X-ray maps.

Pulmonary bioavailability of ascorbic acid in an ascorbate-synthesising species, the horse.

PubMed

Deaton, Christopher M; Marlin, David J; Smith, Nicola C; Roberts, Colin A; Harris, Pat A; Kelly, Frank J; Schroter, Robert C

2003-04-01

Vitamin C (ascorbic acid) is a non-enzymatic antioxidant important in protecting the lung against oxidative damage and is decreased in lung lining fluid of horses with airway inflammation. To examine possible therapeutic regimens in a species with ascorbate-synthesising capacity, we studied the effects of oral supplementation of two forms of ascorbic acid, (each equivalent to 20 mg ascorbic acid per kg body weight) on the pulmonary and systemic antioxidant status of six healthy ponies in a 3 x 3 Latin square design. Two weeks supplementation with ascorbyl palmitate significantly increased mean plasma ascorbic acid concentrations compared to control (29 +/- 5 and 18 +/- 7 micromol/l, respectively; p < 0.05). Calcium ascorbyl-2-monophosphate, a more stable form of ascorbic acid, also increased mean plasma ascorbic acid concentrations, but not significantly (23 +/- 1 micromol/l; p = 0.07). The concentration of ascorbic acid in bronchoalveolar lavage fluid increased in five out of six ponies following supplementation with either ascorbyl palmitate or calcium ascorbyl-2-monophosphate compared with control (30 +/- 10, 25 +/- 4 and 18 +/- 8 micromol/l, respectively; p < 0.01). Neither supplement altered the concentration of glutathione, uric acid or alpha-tocopherol in plasma or bronchoalveolar lavage fluid. In conclusion, the concentration of lung lining fluid ascorbic acid is increased following ascorbic acid supplementation (20 mg/kg body weight) in an ascorbate-synthesising species.

Amino substituted Cu3(btc)2: a new metal-organic framework with a versatile functionality.

PubMed

Peikert, Katharina; Hoffmann, Frank; Fröba, Michael

2012-11-25

A new amino substituted tricarboxylate linker and the new metal-organic framework Cu(3)(NH(2)btc)(2) have been synthesised. The new MOF shows good adsorption properties and is suitable for postsynthetic modification to form an amide functionalised framework.

Cu(3)(BTC)(2) as a viable heterogeneous solid catalyst for Friedel-Crafts alkylation of indoles with nitroalkenes.

PubMed

Nagaraj, Anbu; Amarajothi, Dhakshinamoorthy

2017-05-15

In the present work, Friedel-Crafts alkylation reaction of indole with β-nitrostyrene is examined using a readily available copper based metal-organic frameworks (MOFs) namely, Cu 3 (BTC) 2 (BTC: 1,3,5-benzenetricarboxylic acid) as solid catalyst under mild reaction conditions. Among the various catalysts screened for this reaction, Cu 3 (BTC) 2 exhibits higher activity under the optimized reaction conditions. Besides the absence of leaching of active sites, it is also observed that the catalyst can be reused for four cycles with a minimal decrease in its activity. Cu 3 (BTC) 2 is used as a catalyst to synthesise a series of heterocyclic compounds with different indole and β-nitrostyrene derivatives in moderate to high yields. The present catalytic system shows comparable activity against to recent reports but the advantage of Cu 3 (BTC) 2 is that it does not require any post-functionalization and above all it can be readily synthesised, thus contributing to the synthesis of heterocyclic compounds with high biological interest. Copyright © 2017 Elsevier Inc. All rights reserved.

Vector Antenna and Maximum Likelihood Imaging for Radio Astronomy

DTIC Science & Technology

2016-03-05

Maximum Likelihood Imaging for Radio Astronomy Mary Knapp1, Frank Robey2, Ryan Volz3, Frank Lind3, Alan Fenn2, Alex Morris2, Mark Silver2, Sarah Klein2...haystack.mit.edu Abstract1— Radio astronomy using frequencies less than ~100 MHz provides a window into non-thermal processes in objects ranging from planets...observational astronomy . Ground-based observatories including LOFAR [1], LWA [2], [3], MWA [4], and the proposed SKA-Low [5], [6] are improving access to

GEMINI-TITAN (GT)-9 TEST - ASTRONAUT BEAN, ALAN - KSC

NASA Image and Video Library

1973-08-14

S73-31973 (August 1973) --- Scientist-astronaut Owen K. Garriott, Skylab 3 science pilot, looks at a map of Earth at the food table in the ward room of the Orbital Workshop (OWS). In this photographic reproduction taken from a television transmission made by a color TV camera aboard the Skylab space station cluster in Earth orbit. Photo credit: NASA

APPA: Association of Higher Education Facilities Officers Educational Conference and Annual Meeting Proceedings (82nd, Philadelphia, Pennsylvania, July 16-18, 1995).

ERIC Educational Resources Information Center

APPA: Association of Higher Education Facilities Officers, Alexandria, VA.

The 23 papers presented in this Proceedings are grouped into four categories: business management; facilities planning, design, and construction; human resource management; and energy and environment. Papers are: (1) "A Business Approach to the Facility Function" (Alan B. Abramson); (2) "Management by Strategic Planning" (Jerry C. Black); (3)…

Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (82nd, New Orleans, Louisiana, August 3-8, 1999). Public Relations.

ERIC Educational Resources Information Center

Association for Education in Journalism and Mass Communication.

The Public Relations section of the Proceedings contains the following 8 papers: "The Cultural Competence Spiral: An Assessment and Profile of U.S. Public Relations Practitioners' Preparation for International Assignments" (Alan R. Freitag); "Trust, Communication, and Quality Relationships in the Workplace: Comparing Views of CEOs…

Synthesis of square-planar aluminum(III) complexes.

PubMed

Thompson, Emily J; Myers, Thomas W; Berben, Louise A

2014-12-15

The synthesis of two four-coordinate and square planar (SP) complexes of aluminum(III) is presented. Reaction of a phenyl-substituted bis(imino)pyridine ligand that is reduced by two electrons, Na2((Ph)I2P(2-)), with AlCl3 afforded five-coordinate [((Ph)I2P(2-))Al(THF)Cl] (1). Square-planar [((Ph)I2P(2-))AlCl] (2) was obtained by performing the same reaction in diethyl ether followed by lyphilization of 2 from benzene. The four-coordinate geometry index for 2, τ4, is 0.22, where 0 would be a perfectly square-planar molecule. The analogous aluminum hydride complex, [((Ph)I2P(2-))AlH] (3), is also square-planar, and was characterized crystallographically and has τ4=0.13. Both 2 and 3 are Lewis acidic and bind 2,6-lutidine. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reduction Pathways of Cyclooctatetraene Iron Tricarbonyl as Examined Using Infrared Spectroelectrochemistry.

DTIC Science & Technology

1987-09-25

173/175/179 potentiostat system was used for voltammetric measurements and thin-layer electrolyses . Cyclooctatetraene iron tricarbonyl was synthesised...the subsequent addftion of water . 3 The infrared spectrum for this species contains similar features to those, in Fig. 3B, including a band around 1670

Seminal plasma removal by density-gradient centrifugation is superior for goat sperm preservation compared with classical sperm washing.

PubMed

Santiago-Moreno, J; Esteso, M C; Castaño, C; Toledano-Díaz, A; Delgadillo, J A; López-Sebastián, A

2017-06-01

Seminal plasma removal is routine in goat sperm cryopreservation protocols. The classical washing procedure designed to accomplish this usually leaves the pellet resulting from use of this procedure contaminated with dead sperm, debris, and cells other than sperm. This contamination negatively affects viability of sperm after cryopreservation. The present research was conducted to compare the effect on chilled and frozen-thawed goat sperm of the classical washing method to that of a selective washing method involving density gradient centrifugation (DGC). In the first experiment, sperm variables were measured in freshly collected sperm, and again after its washing with both methods and chilling at 5°C for 0, 3, 24, 48, 72 or 96h. The DGC-washed sperm had greater (P<0.01) straight line velocity (VSL), average path velocity (VAP) and progression ratio values at all chilling times. The amplitude of lateral head displacement (ALH) was, however, less (P<0.001) in the DGC-washed sperm at all chilling times. There was a negative correlation (P<0.05) between ALH and VSL. In the second experiment involving the freezing-thawing of sperm washed by using either method, aliquots were post-wash diluted with a Tris-citric acid/glucose/egg yolk/glycerol-based medium and frozen in liquid nitrogen for 5days. After thawing, neither the VCL, VSL nor VAP of the DGC-washed samples were affected, whereas the traditionally washed samples had less motility. In conclusion, the use of DGC was associated with enhanced sperm motility variables after chilling and freezing-thawing. This procedure would, therefore, be a useful means of removing seminal plasma from goat semen and obtaining greater quality sperm for insemination purposes. Copyright © 2017. Published by Elsevier B.V.

Observation and Analysis of In Situ Carbonaceous Matter in Naklha. Part 2

NASA Technical Reports Server (NTRS)

Gibson, E. K., Jr.; Clemett, S. J.; Thomas-Kerpta, K. L.; McKay, D. S.; Wentworth, S. J.; Robert, F.; Verchovsky, A. B.; Wright, I. P.; Pillinger, C. T.; Rice, T.;

Synthesis and characterisation of the uranium pyrochlore betafite [(Ca,U)₂(Ti,Nb,Ta)₂O₇].

PubMed

McMaster, Scott A; Ram, Rahul; Charalambous, Fiona; Pownceby, Mark I; Tardio, James; Bhargava, Suresh K

2014-09-15

Betafite of composition [(Ca,U)2(Ti,Nb,Ta)2O7] was prepared via a solid state synthesis route. The synthesis was shown to be sensitive to initial reactant ratios, the atmosphere used (oxidising, neutral, reducing) and time. The optimum conditions for the synthesis of betafite were found to be heating the reactants required at 1150°C for 48 h under an inert gas atmosphere. XRD characterisation revealed that the synthesised betafite contained minor impurities. EPMA analysis of a sectioned surface showed very small regions of Ca-free betafite on grain boundaries as well as minor rutile impurities. Some heterogeneity between the Nb:Ta ratio was observed by quantitative EPMA but was generally within the nomenclature requirements stated for betafite. SEM analysis revealed the synthesised betafite was comprised mostly of hexaoctohedral crystals of ∼ 3 μm in diameter. XPS analysis of the sample showed that the uranium in the synthesised betafite was predominately present in the U(5+) oxidation state. A minor amount of U(6+) was also detected which was possibly due to surface oxidation. Copyright © 2014 Elsevier B.V. All rights reserved.

Calcium silicates synthesised from industrial residues with the ability for CO2 sequestration.

PubMed

Morales-Flórez, Victor; Santos, Alberto; López, Antonio; Moriña, Isabel; Esquivias, Luis

2014-12-01

This work explored several synthesis routes to obtain calcium silicates from different calcium-rich and silica-rich industrial residues. Larnite, wollastonite and calcium silicate chloride were successfully synthesised with moderate heat treatments below standard temperatures. These procedures help to not only conserve natural resources, but also to reduce the energy requirements and CO2 emissions. In addition, these silicates have been successfully tested as carbon dioxide sequesters, to enhance the viability of CO2 mineral sequestration technologies using calcium-rich industrial by-products as sequestration agents. Two different carbon sequestration experiments were performed under ambient conditions. Static experiments revealed carbonation efficiencies close to 100% and real-time resolved experiments characterised the dynamic behaviour and ability of these samples to reduce the CO2 concentration within a mixture of gases. The CO2 concentration was reduced up to 70%, with a carbon fixation dynamic ratio of 3.2 mg CO2 per g of sequestration agent and minute. Our results confirm the suitability of the proposed synthesis routes to synthesise different calcium silicates recycling industrial residues, being therefore energetically more efficient and environmentally friendly procedures for the cement industry. © The Author(s) 2014.

Experimental Impacts into Chondritic Targets. Part 1; Disruption of an L6 Chondrite by Multiple Impacts

NASA Technical Reports Server (NTRS)

Cintala, Mark J.; Horz, Friedrich

2007-01-01

A fragment of an L6 chondrite (ALH 85017,13) with an initial mass (M(sub 0)) of 464.1 g was the target in a series of experimental impacts in which the largest remaining fragment (M(sub R)) after each shot was impacted by a 3.18-mm ceramic sphere at a nominal speed of 2 km/s. This continued until the mass of the largest remaining piece was less than half the mass of the target presented to that shot (M(sub S)). Two chunks of Bushveldt gabbro with similar initial masses were also impacted under the same conditions until M(sub R) was less than half M(sub 0). The two gabbro targets required a total of 1.51x10(exp 7) and 1.75x10(exp 7) erg/g to attain 0.27 and 0.33 M(sub R)/M(sub 0), respectively; the chondrite, however, was considerably tougher, reaching 0.40 and 0.21 M(sub R)/M(sub 0) only after receiving 2.37x10(exp 7) and 3.10x10(exp 7) erg g-1, respectively. The combined ejecta and spallation products from the gabbro impacts were coarser than those from the chondrite and in sufficient quantities that the new surface areas exceeded those from the meteorite until the fifth shot in the chondrite series, which was the number of impacts required to disrupt each gabbro target (i.e., MR/M0 = 0.5). Unlike the behavior shown in previous regolith-evolution series, neither gabbro target produced an enhancement in the size fraction reflecting the mean size of the crystals composing the rock (about 3 mm), an effect possibly related to the width of the shock pulse. The original chondrite was so fine-grained and fractured, and the variance in its grain-size distribution so large, that effects related to grain-size were relegated to the <63- m fraction. Impacts into ALH 85017 produced abundant, fine-grained debris, but otherwise the slopes of its size distributions were comparable to those from other experiments involving natural and fabricated terrestrial targets. The characteristic slopes of the chondrite's size distributions, however, were notably more constant over the entire nine-impact series than those from any of the terrestrial targets, a testament to the control over comminution apparently exerted by pre-existing fractures and other, microscopic damage in the meteorite. The enhancement in the finer fraction of debris from ALH 85017 indicates that ordinary chondrites in solar orbit would be very efficient contributors to the cosmic-dust complex. At the same time, the greater resistance to disruption displayed by ordinary chondrites relative to that exhibited by igneous rocks indicates that a selection effect could be operative between the annealed, ordinary-chondritic breccias and relatively weaker, differentiated meteorites. Preferential survival from their time in the regoliths of their parent bodies through their transit to Earth and passage through the atmosphere suggests that meteorite collections could be biased in favor of the ordinary chondrites.

Astronaut Jack Lousma - Inflight Medical Support System (IMSS) - JSC

NASA Image and Video Library

1973-01-01

S73-28423 (16 June 1973) --- Astronaut Jack R. Lousma, Skylab 3 pilot, reaches into a medical kit, part of the Inflight Medical Support System (IMSS), during training for the second manned Skylab Earth-orbital mission. This activity took place in the OWS trainer in the Mission Simulation and Training Facility at the Johnson Space Center (JSC). Other Skylab 3 crewmen are astronaut Alan L. Bean, commander, and scientist-astronaut Owen K. Garriott, science pilot. Photo credit: NASA

Skylab 3 crew during press conference

NASA Image and Video Library

1973-06-30

S73-30110 (30 June 1973) --- The three members of the prime crew of the second manned Skylab mission (Skylab 3) discuss their scheduled 56-day flight before a gathering of news media representatives in the large auditorium of Building 1 at the Johnson Space Center (JSC), Houston, Texas, on June 30, 1973. They are, left to right, astronaut Alan L. Bean, commander; scientist-astronaut Owen K. Garriott, science pilot; and astronaut Jack R. Lousma, pilot. Photo credit: NASA

Astronaut Alan Bean holds Special Environmental Sample Container

NASA Image and Video Library

1969-11-20

AS12-49-7278 (19-20 Nov. 1969) --- Astronaut Alan L. Bean holds a Special Environmental Sample Container filled with lunar soil collected during the extravehicular activity (EVA) in which astronauts Charles Conrad Jr., commander, and Bean, lunar module pilot, participated. Conrad, who took this picture, is reflected in Bean's helmet visor. Conrad and Bean descended in the Apollo 12 Lunar Module (LM) to explore the lunar surface while astronaut Richard F. Gordon Jr., command module pilot, remained with the Command and Service Modules (CSM) in lunar orbit. Photo credit: NASA

Apollo 12 Mission image - Dark view of Astronaut Alan L. Bean climbing down the ladder of the Lunar Module (LM)

NASA Image and Video Library

1969-11-19

AS12-46-6726 (19 Nov. 1969) --- Astronaut Alan L. Bean, lunar module pilot for the Apollo 12 mission, starts down the ladder of the Lunar Module (LM) to join astronaut Charles Conrad Jr., mission commander, in extravehicular activity (EVA). While astronauts Conrad and Bean descended in the LM "Intrepid" to explore the Ocean of Storms region of the moon, astronaut Richard F. Gordon Jr., command module pilot, remained with the Command and Service Modules (CSM) "Yankee Clipper" in lunar orbit.

The Influence of the Competition in Contracting Act on the Volume of Competitive Prime Contract Awards for Major Hard Goods and Non-Major Hard Goods Purchased by the Department of Defense

DTIC Science & Technology

1988-11-16

parts was less than for sole source acquired spare parts see, Alan E. Olsen ; James E. Cunningham; and Donald J. Wilkins, "A Cost-Benefit Analysis of...Washington, D.C. Logistc Management-Institute, MUTT- I 339 I Zusman, Morris; Asher, Norman; Wetzler, Elliot; Bennett, Debbie; Gustaves, Selmer ; Higgins...Acquisition." Masters Thesis, Naval Postgraduate School, 1984. Olsen , Alan E.; Cunningham, James E.; and Wilkins, Donald J. "A Cost-Benefit Analysis of

METEORITE - ASTRONOMY

NASA Image and Video Library

1985-08-28

S85-39565 (For release August 1996) --- According to scientists, this 4.5 billion year old rock, labeled meteorite ALH84001, is believed to have once been a part of Mars and to contain fossil evidence that primitive life may have existed on Mars more than 3.6 billion years ago. The rock is a portion of a meteorite that was dislodged from Mars by a huge impact about 16 million years ago and that fell to Earth in Antarctica 13,000 years ago. The meteorite was found in Allan Hills ice field, Antarctica, by an annual expedition of the National Science Foundation?s Antarctic Meteorite Program in 1984. It is preserved for study at the Johnson Space Center?s (JSC) Meteorite Processing Laboratory in Houston, Texas.

The removal of uranium onto carbon-supported nanoscale zero-valent iron particles

NASA Astrophysics Data System (ADS)

Crane, Richard A.; Scott, Thomas

2014-12-01

In the current work carbon-supported nanoscale zero-valent iron particles (CS nZVI), synthesised by the vacuum heat treatment of ferric citrate trihydrate absorbed onto carbon black, have been tested for the removal of uranium (U) from natural and synthetic waters. Two types of CS nZVI were tested, one vacuum annealed at 600 °C for 4 h and the other vacuum annealed at 700 °C for 4 h, with their U removal behaviour compared to nZVI synthesised via the reduction of ferrous iron using sodium borohydride. The batch systems were analysed over a 28-day reaction period during which the liquid and nanoparticulate solids were periodically analysed to determine chemical evolution of the solutions and particulates. Results demonstrate a well-defined difference between the two types of CS nZVI, with greater U removal exhibited by the nanomaterial synthesised at 700 °C. The mechanism has been attributed to the CS nZVI synthesised at 700 °C exhibiting (i) a greater proportion of surface oxide Fe2+ to Fe3+ (0.34 compared to 0.28); (ii) a greater conversion of ferric citrate trihydrate [2Fe(C6H5O7)·H2O] to Fe0; and (iii) a larger surface area (108.67 compared to 88.61 m2 g-1). Lower maximum U uptake was recorded for both types of CS nZVI in comparison with the borohydride-reduced nZVI. A lower decrease in solution Eh and DO was also recorded, indicating that less chemical reduction of U was achieved by the CS nZVI. Despite this, lower U desorption in the latter stages of the experiment (>7 days) was recorded for the CS nZVI synthesised at 700 °C, indicating that carbon black in the CS nZVI is likely to have contributed towards U sorption and retention. Overall, it can be stated that the borohydride-reduced nZVI were significantly more effective than CS nZVI for U removal over relatively short timescales (e.g. <48 h), however, they were more susceptible to U desorption over extended time periods.

STUDIES ON THE ORIGIN OF CIRCULATING 18-HYDROXYCORTISOL AND 18-OXOCORTISOL IN NORMAL HUMAN SUBJECTS.

PubMed Central

Freel, E Marie; Shakerdi, Loai A; Friel, Elaine C; Wallace, A Michael; Davies, Eleanor; Fraser, Robert; Connell, John MC

2005-01-01

18-hydroxycortisol (18-OHF) and 18-oxocortisol (18oxo-F) are derivatives of cortisol found in Primary Aldosteronism but whose origin and regulation in normal subjects is uncertain. 18-OHF can be synthesised by zona fasciculata 11-β hydroxylase; 18-oxoF can only be produced by zona glomerulosa aldosterone synthase (AS). Stably transfected cell lines expressing either CYP11B1 (11β-hydroxylase) or CYP11B2 (AS) were incubated with cortisol and other substrates over a range of concentrations. Both enzymes could synthesise 18-OHF from cortisol but only AS could synthesise 18-oxoF. AS was more efficient than 11β-hydroxylase at 18-hydroxylation. The apparent Km of AS for cortisol was estimated to be 2.6μM. In 5 patients with adrenal insufficiency maintained on hydrocortisone, urinary free cortisol and cortisone levels were high; 18-oxoF was detectable in all patients and 18-hydroxycortisol in 3. It is likely that the 18-oxygenated steroids were synthesised from circulating cortisol, either in the zona glomerulosa or at extra-adrenal sites. In 8 male volunteers, dexamethasone treatment decreased urinary excretion rates of free cortisol, cortisone, 18-OHF and 18-oxoFl, confirming dependence of 18-oxygenated steroid levels on cortisol availability. In both groups, hydrocortisone administration resulted in detectable levels of 18-OHF and raised levels of 18-oxoF. There was close correlation between 18-oxoF and cortisol excretion during hydrocortisone administration in normal subjects (r=0.86, p<0.001). These data show, for the first time, that 18-OHF and 18oxoF can be synthesised from circulating cortisol. The close correlation between 18-oxoF and cortisol suggests that 18-oxoF is normally produced by the action of aldosterone synthase utilising circulating cortisol as a substrate. Although 18OHF can be synthesized using circulating cortisol as substrate, our data suggest this is normally produced in the zona fasciculata by 11β-hydroxylase from locally available cortisol. PMID:15356073

Analysis of the bonding in XH3Cu+ (XB, Al, Ga) complexes

NASA Astrophysics Data System (ADS)

Corral, Inés; Mó, Otilia; Yáñez, Manuel

High-level density functional theory (DFT) calculations on XH3Cu+ (XB, Al, Ga) complexes show that the attachment of the metal cation to the base takes place through agostic-type interactions. These interactions that can be viewed as dative bonds from the σXH bonding orbitals of the base toward low-lying empty 4s orbitals of the metal cation, and back-donations from the lone pairs of the metal into the σ *XH antibonding orbitals of the neutral, are particularly favored when the XH bonds have a high X+δH-δ polarity. Accordingly, the AlH3 and GaH3 Cu+ binding energies are very similar, but much larger than that of BH3. Depopulation of the σXH bonding orbital and the concomitant population of the σ *XH antibonding orbital involved in the agostic interaction result in a significant weakening of the corresponding XH linkages, whose bond length increases and whose stretching frequency appears red-shifted.

First Principles Based Simulation of Reaction-Induced Phase Transition in Hydrogen Storage and Other Materials

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

Ge, Qingfeng

2014-08-31

This major part of this proposal is simulating hydrogen interactions in the complex metal hydrides. Over the period of DOE BES support, key achievements include (i) Predicted TiAl 3Hx as a precursor state for forming TiAl 3 through analyzing the Ti-doped NaAlH 4 and demonstrated its catalytic role for hydrogen release; (ii) Explored the possibility of forming similar complex structures with other 3d transition metals in NaAlH 4 as well as the impact of such complex structures on hydrogen release/uptake; (iii) Demonstrated the role of TiAl 3 in hydriding process; (iv) Predicted a new phase of NaAlH 4 that linksmore » to Na3AlH6 using first-principles metadynamics; (v) Examined support effect on hydrogen release from supported/encapsulated NaAlH 4; and (vi) Expanded research scope beyond hydrogen storage. The success of our research is documented by the peer-reviewed publications.« less

Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (82nd, New Orleans, Louisiana, August 3-8, 1999). International Communication, Part 2.

ERIC Educational Resources Information Center

Association for Education in Journalism and Mass Communication.

The International Communication, Part 2 section of the Proceedings contains the following 8 papers: "Split Images: Arab and Asian Political Leaders' Portraits in Major U.S. News Magazines" (Hye-Kyeong Pae); "Public Relations Functions and Models: U.S. Practitioners in International Assignments" (Alan R. Freitag); "The…

Using Computers Intelligently in Tertiary Education. A Collection of Papers Presented to the Australian Society for Computers in Learning (Sydney, New South Wales, Australia, November 29-December 3, 1987).

ERIC Educational Resources Information Center

Barrett, John, Ed.; Hedberg, John, Ed.

The 63 papers in this collection include two keynote addresses: "Patient Simulation Using Interactive Video: An Application" (Joseph V. Henderson), and "Intelligent Tutoring Systems: Practice Opportunities and Explanatory Models" (Alan Lesgold). The remaining papers are grouped under five topics: (1) Artificial Intelligence,…

Microcomputers in Education: Uses for the '80s. Proceedings of the Annual Microcomputer Conference (2nd, Tempe, Arizona, January 15-16, 1982). Publication No. 3.

ERIC Educational Resources Information Center

Watson, Nancy Ralph, Ed.

The 30 conference papers in this collection are presented in 6 categories. Five overviews discuss innovative uses of computers in education (Dorothy K. Deringer); microcomputers in instructional research (Alan M. Lesgold); microcomputers in the schools (Mitchell Batoff, Gary G. Bitter); and the courseware crisis (Barbara R. Sadowski). Research and…

Surfactant-free bio-synthesised Tio2 nanorods from Turbinaria conoides-a study on photocatalytic and anti-bacterial activity

NASA Astrophysics Data System (ADS)

Subhapriya, S.; Gomathipriya, P.

2018-06-01

In this study, Titania nanorods were synthesised from aqueous extract of Turbinaria conoides (brown seaweeds) (TiO2NRs-TC) under surfactant free medium. The photocatalytic activity of the synthesised nanorods was tested towards the photocatalytic decolourization using simulated dye wastewater containing Navy Blue HER (NBHER). The synthesised Titania nanorods were characterized by using x-ray diffraction (XRD), UV–visible spectroscopy (UV–vis), Scanning Electron Microscopy (SEM), Energy Dispersive Spectrophotometer (EDS) and Transmission Electron Microscopy (TEM). XRD pattern confirms the anatase phase formation and HR-SEM micrograph shows the presence of rod like structure with the size of about 50 nm. TEM analysis proves the rod like structure with a size of 45–50 nm which was in agreement with the XRD analysis and HR-SEM images. EDS and XDS confirmed the formation of Titania nanoparticles. The formation of TiO2NRs-TC has a beneficial influence on the dye Navy blue HER photodegradation. TiO2-TC nano rods also show superior photocatalytic ability in hydrogen generation (2.1 mmol/h‑1g‑1). The antibacterial activity of the synthesised nanoparticles was examined using disc diffusion method which showed diverse susceptibility of microorganisms to the Titania nanoparticles.

Production of palm kernel shell-based activated carbon by direct physical activation for carbon dioxide adsorption.

PubMed

Rashidi, Nor Adilla; Yusup, Suzana

2018-05-09

The feasibility of biomass-based activated carbons has received a huge attention due to their excellent characteristics such as inexpensiveness, good adsorption behaviour and potential to reduce a strong dependency towards non-renewable precursors. Therefore, in this research work, eco-friendly activated carbon from palm kernel shell that has been produced from one-stage physical activation by using the Box-Behnken design of Response Surface Methodology is highlighted. The effect of three input parameters-temperature, dwell time and gas flow rate-towards product yield and carbon dioxide (CO 2 ) uptake at room temperature and atmospheric pressure are studied. Model accuracy has been evaluated through the ANOVA analysis and lack-of-fit test. Accordingly, the optimum condition in synthesising the activated carbon with adequate CO 2 adsorption capacity of 2.13 mmol/g and product yield of 25.15 wt% is found at a temperature of 850 °C, holding time of 60 min and CO 2 flow rate of 450 cm 3 /min. The synthesised activated carbon has been characterised by diverse analytical instruments including thermogravimetric analyser, scanning electron microscope, as well as N 2 adsorption-desorption isotherm. The characterisation analysis indicates that the synthesised activated carbon has higher textural characteristics and porosity, together with better thermal stability and carbon content as compared to pristine palm kernel shell. Activated carbon production via one-step activation approach is economical since its carbon yield is within the industrial target, whereas CO 2 uptake is comparable to the synthesised activated carbon from conventional dual-stage activation, commercial activated carbon and other published data from literature.

Synthesis of SiC nanoparticles by SHG 532 nm Nd:YAG laser ablation of silicon in ethanol

NASA Astrophysics Data System (ADS)

Khashan, Khawla S.; Ismail, Raid A.; Mahdi, Rana O.

2018-06-01

In this work, colloidal spherical nanoparticles NPs of silicon carbide SiC have been synthesized using second harmonic generation 532 nm Nd:YAG laser ablation of silicon target dipped in ethanol solution at various laser fluences (1.5-5) J/cm2. X-Ray diffraction XRD, scanning electron microscopy SEM, transmission electron microscope TEM, Fourier transformed infrared spectroscopy FT-IR, Raman spectroscopy, photoluminescence PL spectroscopy, and UV-Vis absorption were employed to examine the structural, chemical and optical properties of SiC NPs. XRD results showed that all synthesised SiC nanoparticles are crystalline in nature and have hexagonal structure with preferred orientation along (103) plane. Raman investigation showed three characteristic peaks 764,786 and 954 cm-1, which are indexing to transverse optic TO phonon mode and longitudinal optic LO phonon mode of 4H-SiC structure. The optical absorption data showed that the values of optical energy gap of SiC nanoparticles prepared at 1.5 J/cm2 was 3.6 eV and was 3.85 eV for SiC synthesised at 5 J/cm2. SEM investigations confirmed that the nanoparticles synthesised at 5 J/cm2 are agglomerated to form larger particles. TEM measurements showed that SiC particles prepared at 1.5 J/cm2 have spherical shape with average size of 25 nm, while the particles prepared at 5 J/cm2 have an average size of 55 nm.

Nocturnal light pollution and underexposure to daytime sunlight: Complementary mechanisms of circadian disruption and related diseases.

PubMed

Smolensky, Michael H; Sackett-Lundeen, Linda L; Portaluppi, Francesco

2015-01-01

Routine exposure to artificial light at night (ALAN) in work, home, and community settings is linked with increased risk of breast and prostate cancer (BC, PC) in normally sighted women and men, the hypothesized biological rhythm mechanisms being frequent nocturnal melatonin synthesis suppression, circadian time structure (CTS) desynchronization, and sleep/wake cycle disruption with sleep deprivation. ALAN-induced perturbation of the CTS melatonin synchronizer signal is communicated maternally at the very onset of life and after birth via breast or artificial formula feedings. Nighttime use of personal computers, mobile phones, electronic tablets, televisions, and the like--now epidemic in adolescents and adults and highly prevalent in pre-school and school-aged children--is a new source of ALAN. However, ALAN exposure occurs concomitantly with almost complete absence of daytime sunlight, whose blue-violet (446-484 nm λ) spectrum synchronizes the CTS and whose UV-B (290-315 nm λ) spectrum stimulates vitamin D synthesis. Under natural conditions and clear skies, day/night and annual cycles of UV-B irradiation drive corresponding periodicities in vitamin D synthesis and numerous bioprocesses regulated by active metabolites augment and strengthen the biological time structure. Vitamin D insufficiency and deficiency are widespread in children and adults in developed and developing countries as a consequence of inadequate sunlight exposure. Past epidemiologic studies have focused either on exposure to too little daytime UV-B or too much ALAN, respectively, on vitamin D deficiency/insufficiency or melatonin suppression in relation to risk of cancer and other, e.g., psychiatric, hypertensive, cardiac, and vascular, so-called, diseases of civilization. The observed elevated incidence of medical conditions the two are alleged to influence through many complementary bioprocesses of cells, tissues, and organs led us to examine effects of the totality of the artificial light environment in which humans reside today. Never have chronobiologic or epidemiologic investigations comprehensively researched the potentially deleterious consequences of the combination of suppressed vitamin D plus melatonin synthesis due to life in today's man-made artificial light environment, which in our opinion is long overdue.

U.S. Airline Transport Pilot International Flight Language Experiences, Report 3: Language Experiences in Non-Native English-Speaking Airspace/Airports

DTIC Science & Technology

2010-05-01

Aviation Administration Oklahoma City, OK 73125 Alan Campbell Johns Creek, GA 30022 Alfred M. Hendrix Ruby Hendrix HCS Consulting Services Roswell , NM...OK 73125 2A. Campbell, Johns Creek, GA, 30022 3HCS Consulting Service, Roswell , NM 88201 12. Sponsoring Agency name and Address 13. Type...52 was making its third approach into JFK Airport and failed to inform air traffic control they had a fuel emergency and crashed . 2 In November

HF Radio Astronomy from a Small Satellite

DTIC Science & Technology

2016-06-15

SSC16-XI-03 HF Radio Astronomy from a Small Satellite Frank C. Robey1, Mary Knapp2, Alan J. Fenn1, Mark Silver1, Kerry Johnson1 Frank J. Lind3...frequency end of the electromagnetic spectrum (below 15 MHz) is one of the least explored windows in observational astronomy . Observations at these...pdf. [Accessed: 17-Oct-2015]. 3. G. Hallinan, “The Owens Valley LWA,” in Exascale Radio Astronomy , 2014, vol. 2. 4. C. J. Lonsdale, R. J. Cappallo

Propagation of 3-D Beams Using a Finite-Difference Algorithm: Practical Considerations

DTIC Science & Technology

2011-05-22

electric-discharge laser ,” J. Appl. Phys. 49(3), 1012–1027 (1978). [6] Sziklas, E. A. and Siegman , A. E., “Mode calculations in unstable resonators with...flowing saturable gain .2. fast fourier-transform method,” Applied Optics 14(8), 1874–1889 (1975). [7] Siegman , A. E., [ Lasers ], University Science...Signed// ALAN H. PAXTON, DR-III Project Manager //Signed// MICHAEL F. SHEEHAN, DR-III, DAF Acting Chief, Laser Division This report is published in

Skylab 3 crewmen shown eating in Orbital Workshop wardroom

NASA Image and Video Library

1973-08-01

S73-31705 (1 Aug. 1973) --- The three Skylab 3 crewmen are shown eating in the Orbital Workshop (OWS) wardroom of the Skylab space station in Earth orbit, in this photographic reproduction taken from a television transmission made by a color TV camera aboard the OWS. Astronaut Alan L. Bean (right), commander, illustrates eating under zero-gravity conditions upsidedown. The two other crewmen are scientist-astronaut Owen K. Garriott (left), science pilot; and astronaut Jack R. Lousma, pilot. Photo credit: NASA

Two step novel hydrogen system using additives to enhance hydrogen release from the hydrolysis of alane and activated aluminum

DOEpatents

Zidan, Ragaiy; Teprovich, Joseph A.; Motyka, Theodore

2015-12-01

A system for the generation of hydrogen for use in portable power systems is set forth utilizing a two-step process that involves the thermal decomposition of AlH.sub.3 (10 wt % H.sub.2) followed by the hydrolysis of the activated aluminum (Al*) byproduct to release additional H.sub.2. Additionally, a process in which water is added directly without prior history to the AlH.sub.3:PA composite is also disclosed.

Skylab 3 crew during training in Orbital Workshop trainer

NASA Technical Reports Server (NTRS)

1973-01-01

The three prime crewmen of the Skylab 3 mission check over flight data during a training session in the crew quarters of the Orbital Workshop (OWS) trainer in the Mission Simulation and Training Facility at JSC. They are from left to right, Scientist-Astronaut Owen K. Garriott, science pilot; and Astronauts Alan L. bean, commander, and Jack R. Lousma, pilot (28419); Skylab 3 crew work with Inflight Medical Support System (IMSS) resupply container atop the food table in the OWS. From left to right are Garriott, Lousma and Bean (28420).

Skylab (SL)-3 Crew - Training - Orbital Workshop Trainer - JSC

NASA Image and Video Library

1973-06-16

S73-28420 (16 June 1973) --- The three prime crewmen of the Skylab 3 mission check over flight data during a training session in the crew quarters of the Orbital Workshop (OWS) trainer in the Mission Simulation and Training Facility at the Johnson Space Center (JSC). Skylab 3 crew work with Inflight Medical Support System (IMSS) resupply container atop the food table in the OWS. They are from left to right, scientist-astronaut Owen K. Garriott, science pilot; and astronauts Jack R. Lousma, pilot; and Alan L. Bean, commander. Photo credit: NASA

Skylab (SL)-3 Crewmen - Checklist - Crew Quarters - Orbital Workshop Simulator (OWS) Trainer - JSC

NASA Image and Video Library

1973-01-01

S73-28793 (16 July 1973) --- The three crewmen of the second manned Skylab mission (Skylab 3) go over a checklist during preflight training at the Johnson Space Center. They are, left to right, scientist-astronaut Owen K. Garriott, science pilot; astronaut Alan L. Bean, commander; and astronaut Jack R. Lousma, pilot. They are in the crew quarters of the Orbital Workshop trainer in the Mission Training and Simulation Facility, Building 5, at JSC. Skylab 3 is scheduled as a 59-day mission in Earth orbit. Photo credit: NASA

The spectral amplification effect of clouds to the night sky radiance in Madrid

NASA Astrophysics Data System (ADS)

Aubé, M.; Kocifaj, M.; Zamorano, J.; Solano Lamphar, H. A.; Sanchez de Miguel, A.

2016-09-01

Artificial Light at Night (ALAN) may have various environmental impacts ranging from compromising the visibility of astronomical objects to the perturbation of circadian cycles in animals and humans. In the past much research has been carried out to study the impact of ALAN on the radiance of the night sky during clear sky conditions. This was mainly justified by the need for a better understanding of the behavior of ALAN propagation into the environment in order to protect world-class astronomical facilities. More recently, alongside to the threat to the natural starry sky, many issues have emerged from the biological science community. It has been shown that, nearby or inside cities, the presence of cloud cover generally acts as an amplifier for artificial sky radiance while clouds behave as attenuators for remote observers. In this paper we show the spectral behavior of the zenith sky radiance amplification factor exerted by clouds inside a city. We compare in-situ measurements made with the spectrometer SAND-4 with a numerical model applied to the specific geographical context of the Universidad Complutense de Madrid in Spain.

America’s Public Diplomacy Deficit

DTIC Science & Technology

1997-01-01

experienced soldiers that the servrces so desperately need to keep Unfortunately, rt 1s clear that the objectives-resources unbalance will not be resolved...do we square the circle? The obvrous alternative 1s to work closely with our alhes, both to promote world economrc growth and share the security...and predictability in trade relations that led to raped expansion m trade and growth m economic prosperrty Increased trade in turn demanded expansion

Possible Evidence for Life in ALH84001

NASA Technical Reports Server (NTRS)

McKay, David; Gibson, Everett K., Jr.; Thomas-Keprta, Kathie

1999-01-01

Since our original paper Science in August 1996, considerable new data has appeared from laboratories throughout the world, and our own team has had a chance to examine the sample in greater detail. The following summary touches on our original data and interpretation, and points out new data from us and from other groups, and the resulting changes and refinements in interpretations which we have made during the past three years.

Angular distribution of γ rays from neutron-induced compound states of 140La

NASA Astrophysics Data System (ADS)

Okudaira, T.; Takada, S.; Hirota, K.; Kimura, A.; Kitaguchi, M.; Koga, J.; Nagamoto, K.; Nakao, T.; Okada, A.; Sakai, K.; Shimizu, H. M.; Yamamoto, T.; Yoshioka, T.

2018-03-01

The angular distribution of individual γ rays, emitted from a neutron-induced compound-nuclear state via radiative capture reaction of 139La(n ,γ ) has been studied as a function of incident neutron energy in the epithermal region by using germanium detectors. An asymmetry ALH was defined as (NL-NH) /(NL+NH) , where NL and NH are integrals of low- and high-energy region of a neutron resonance respectively, and we found that ALH has the angular dependence of (A cosθγ+B ) , where θγ is the emitted angle of γ rays, with A =-0.3881 ±0.0236 and B =-0.0747 ±0.0105 in 0.74 eV p -wave resonance. This angular distribution was analyzed within the framework of interference between s - and p -wave amplitudes in the entrance channel to the compound-nuclear state, and it is interpreted as the value of the partial p -wave neutron width corresponding to the total angular momentum of the incident neutron combined with the weak matrix element, in the context of the mechanism of enhanced parity-violating effects. Additionally, we use the result to quantify the possible enhancement of the breaking of time-reversal invariance in the vicinity of the p -wave resonance.

Microbial Extremophiles in Evolutionary Aspect

NASA Technical Reports Server (NTRS)

Pikuta, Elena V.; Hoover, Richard B.

2007-01-01

The microflora of the cryosphere of planet Earth provides the best analogs for life forms that might be found in the permafrost or polar ice caps of Mars, near the surface of the cometary nuclei, or in the liquid water beneath the ice crusts of icy moons of Jupiter and Saturn. For astrobiology the focus on the study alkaliphilic microorganisms was enhanced by the findings of abundant carbonates and carbonate globules rimmed with possibly biogenic magnetites in association with the putative microfossils in the ALH84001 meteorite. Although the ALH84001 "nanofossils" were to small and simple to be unambiguously recognized as biogenic, they stimulated Astrobiology research and studies of microbial extremophiles and biomarkers in ancient rocks and meteorites. Recent studies of CI and CM carbonaceous meteorites have resulted in the detection of the well-preserved mineralized remains of coccoidal and" filamentous microorganisms in cyanobacterial mats. Energy Dispersive X-ray Analysis has shown anomalous biogenic element ratios clearly indicating they are not recent biological contaminants. This paper reviews microbial extremophiles in context of their significance to Astrobiology and the evolution of life. Extremophilic microorganisms on Earth are models for life that might endure high radiation environments in the ice near the surface of comets or on the icy moons of Jupiter and Saturn and in the seafloor deep beneath the icy crusts of Europa and Enceladus.

Green-synthesised nanoparticles from Melia azedarach seeds and the cyclopoid crustacean Cyclops vernalis: an eco-friendly route to control the malaria vector Anopheles stephensi?

PubMed

Anbu, Priya; Murugan, Kadarkarai; Madhiyazhagan, Pari; Dinesh, Devakumar; Subramaniam, Jayapal; Panneerselvam, Chellasamy; Suresh, Udaiyan; Alarfaj, Abdullah A; Munusamy, Murugan A; Higuchi, Akon; Hwang, Jiang-Shiou; Kumar, Suresh; Nicoletti, Marcello; Benelli, Giovanni

2016-09-01

The impact of green-synthesised mosquitocidal nanoparticles on non-target aquatic predators is poorly studied. In this research, we proposed a single-step method to synthesise silver nanoparticles (Ag NP) using the seed extract of Melia azedarach. Ag NP were characterised using a variety of biophysical methods, including UV-vis spectrophotometry, scanning electron microscopy, energy-dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. In laboratory assays on Anopheles stephensi, Ag NP showed LC50 ranging from 2.897 (I instar larvae) to 14.548 ppm (pupae). In the field, the application of Ag NP (10 × LC50) lead to complete elimination of larval populations after 72 h. The application of Ag NP in the aquatic environment did not show negative adverse effects on predatory efficiency of the mosquito natural enemy Cyclops vernalis. Overall, this study highlights the concrete possibility to employ M. azedarach-synthesised Ag NP on young instars of malaria vectors.

Synthesis of different-sized silver nanoparticles by simply varying reaction conditions with leaf extracts of Bauhinia variegata L.

PubMed

Kumar, V; Yadav, S K

2012-03-01

Green synthesis of nanoparticles is one of the crucial requirements in today's climate change scenario all over the world. In view of this, leaf extract (LE) of Bauhinia variegata L. possessing strong antidiabetic and antibacterial properties has been used to synthesise silver nanoparticles (SNP) in a controlled manner. Various-sized SNP (20-120 nm) were synthesised by varying incubation temperature, silver nitrate and LE concentrations. The rate of SNP synthesis and their size increased with increase in AgNO(3) concentration up to 4 mM. With increase in LE concentration, size and aggregation of SNP was increased. The size and aggregation of SNP were also increased at temperatures above and below 40°C. This has suggested that size and dispersion of SNP can be controlled by varying reaction components and conditions. Polarity-based fractionation of B. variegata LE has suggested that only water-soluble fraction is responsible for SNP synthesis. Fourier transform infrared spectroscopy analysis revealed the attachment of polyphenolic and carbohydrate moieties to SNP. The synthesised SNPs were found stable in double distilled water, BSA and phosphate buffer (pH 7.4). On the contrary, incubation of SNP with NaCl induced aggregation. This suggests the safe use of SNP for various in vivo applications.

Studies on the biodegradation of fosfomycin: growth of Rhizobium huakuii PMY1 on possible intermediates synthesised chemically.

PubMed

McGrath, John W; Hammerschmidt, Friedrich; Preusser, Werner; Quinn, John P; Schweifer, Anna

2009-05-07

The first step of the mineralisation of fosfomycin by R. huakuii PMY1 is hydrolytic ring opening with the formation of (1R,2R)-1,2-dihydroxypropylphosphonic acid. This phosphonic acid and its three stereoisomers were synthesised by chemical means and tested as their ammonium salts for mineralisation as evidenced by release of P(i). Only the (1R,2R)-isomer was degraded. A number of salts of phosphonic acids such as (+/-)-1,2-epoxybutyl-, (+/-)-1,2-dihydroxyethyl-, 2-oxopropyl-, (S)-2-hydroxypropyl-, (+/-)-1-hydroxypropyl- and (+/-)-1-hydroxy-2-oxopropylphosphonic acid were synthesised chemically, but none supported growth. In vitro C-P bond cleavage activity was however detected with the last phosphonic acid. A mechanism involving phosphite had to be discarded as it could not be used as a phosphorus source. R. huakuii PMY1 grew well on (R)- and (S)-lactic acid and hydroxyacetone, but less well on propionic acid and not on acetone or (R)- and (+/-)-1,2-propanediol. The P(i) released from (1R,2R)-1,2-dihydroxypropylphosphonic acid labelled with one oxygen-18 in the PO3H2 group did not stay long enough in the cells to allow complete exchange of 18O for 16O by enzymic turnover.

Approaches to Establishing the Chemical Structure of Extraterrestrial Organic Solids

NASA Technical Reports Server (NTRS)

Cody, G. D.; Alexander, C. M. OD.; Wirick, Susan

2003-01-01

The majority of extraterrestrial organic matter in carbonaceous chondrites resides in a chemically complex, insoluble and perhaps macromolecular phase. We have been applying a series of independent solid state NMR experiments that are designed to provide a self consistent chemical characterization of this complex material. To date we have thoroughly analyzed 8 organic residues from different meteorites, including a CR2 (EET92042), CIl(Orgueil), CM2 (Murchison), Tagish Lake, CM2 (AlH83100), CM2 (Cold Bokkefeld), CM2 (Mighei), CM3 (Y86720). In fig 1. (1)H to (13)C cross polarization NMR spectra of four of these are shown. Note that there exists an enormous range in chemistry exhibited in organic solid [evident by the breadth of the spectral features both in the aliphatic region (sp(sup 3)) and the aromatic region (sp(sup 2))]. There is also considerable differences in the carbon chemistry across the meteorite groups.

Computational Study of Formic Acid Dehydrogenation Catalyzed by Al(III)-Bis(imino)pyridine.

PubMed

Lu, Qian-Qian; Yu, Hai-Zhu; Fu, Yao

2016-03-18

The mechanism of formic acid dehydrogenation catalyzed by the bis(imino)pyridine-ligated aluminum hydride complex (PDI(2-))Al(THF)H (PDI=bis(imino)pyridine) was studied by density functional theory calculations. The overall transformation is composed of two stages: catalyst activation and the catalytic cycle. The catalyst activation begins with O-H bond cleavage of HCOOH promoted by aluminum-ligand cooperation, followed by HCOOH-assisted Al-H bond cleavage, and protonation of the imine carbon atom of the bis(imino)pyridine ligand. The resultant doubly protonated complex ((H,H) PDI)Al(OOCH)3 is the active catalyst for formic acid dehydrogenation. Given this, the catalytic cycle includes β-hydride elimination of ((H,H) PDI)Al(OOCH)3 to produce CO2, and the formed ((H,H) PDI)Al(OOCH)2 H mediates HCOOH to release H2. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Production of silica gel from Tunisian sands and its adsorptive properties

NASA Astrophysics Data System (ADS)

Lazaar, K.; Hajjaji, W.; Pullar, R. C.; Labrincha, J. A.; Rocha, F.; Jamoussi, F.

2017-06-01

Thanks to its highly absorbent character, silica gel is used in several applications, such as air moisture removal, as a treatment agent for effluents. In this study, silica gels were synthesised from Tunisian sands, collected from the Fortuna and Sidi Aich Formations in northern and central Tunisia. The collected quartz sand raw materials, as well as the prepared silica gels, were characterised by different techniques, such as X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM). XRD patterns of quartz sands showed quartz as main phase (86.1-98%), with lower contents of potassic feldspars, along with kaolinite and calcite. These quartz sands presented relatively small quantities of Fe2O3 (0.3%-0.5%) and TiO2 (0.1%-0.6%). The synthesised silica gels exhibited pore diameters exceeding 20 Å and surface areas up to 194 m2/g, comparable with those described in the literature and commercial silica gel. N2 adsorption isotherms showed that the silica gels prepared from Tunisian sands are mesoporous materials with high adsorption capacities. To understand better their adsorbent properties and applicability on an industrial scale, these gels were tested for methylene blue (MB) absorption. Maximum decolourisation rates (up to 96% after a contact time of 180 min) occurred with products synthesised at pH 3. The adsorption mechanism fitted better with a Langmuir model, revealing a monolayer coverage process of MB molecules over the gel surface, and the adsorption kinetics of the dye on these materials is well described by the second order model. The corresponding equilibrium adsorption capacities obtained from experimental data (Qexp = 292-214 mg/g) were close to the estimated maximum adsorption capacities (Qe = 333-250 mg/g), and to that of an industrial silica gel (250 mg/g).

Proceedings of the Electronics Manufacturing Seminar (13th Annual) Held at China Lake, California on 1-3 March 1989

DTIC Science & Technology

1989-03-01

107 Riccardo Vanzetti and Alan C. Traub Vanzeti Systems, Inc. Stoughton, MA Laser Robotic W ork Cell...O"go, NY New Ad-csive Maei.ls for PWB Assembly ........................................................................ 347 Stephen J. Gangi CHR...solderability performance. This paper addresses four main topics: (1) Section II introduces and describes new solderability indices which may be of value in

UXO Detector for Underwater Surveys Using Low-Frequency Sonar

DTIC Science & Technology

2015-06-01

Oude Waalsdorperweg 63 The Hague The Netherlands 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES...remaining number of false alarms will be further reduced. The application of these two rules to the data shown in Figure 6-3, leads to removal of...Box 96864, 2509 JG The Hague , The Netherlands, +31 88 866 0902, alan.hunter@tno.nl Abstract: Detection of unexploded ordnance is challenging in the

Use of Anti-Idiotypes and Synthetic Peptides for Control of Human T- Lymphotropic Virus Type 3 Infections

DTIC Science & Technology

1988-10-28

FIELD GROUP SUBAGROUP Synthetic peptides, anti-idiotypes, vaccines, 06 03 human immunodeficiency virus, chimpanzees, RAI, Virology, 06 13 HTLV III...suppressive effects have been reported previously with a synthetic peptide analogous to amino acid sequences from the feline leukemia virus...on the use of synthetic peptides in human immunodeficiency virus infection. In Advances in Biotechnological Processes (A. Mizrahi, ed.), Alan R. Liss

Sentence Comprehension: A Parallel Distributed Processing Approach

DTIC Science & Technology

1989-07-14

NAME OF PERFORMING ORGANIZATION 6b OFFICE SYMBOL 7a NAME OF MONITORING ORGANIZATION (If aodkawe) Computer Sciences DivisionCarnegie-Mellon University...Pittsburgh, Pennsylvania 15213. Arlington, Virginia 22217-5000 $a. NAME OF FUNOINGISPONSORING Sb OFFICE SYMBOL 9 PROCUREMENT INSTRUMENT IOENTIFICATION...3 OTIC USERS 22a NAME OF RESPONSIBLE INOIVI0UAL 22b TELEPHONE (include Area COd) 22c. OFFICE SYMBOL Dr. Alan L. Meyrowitz (202) 696-4302 N00014 D0

When Multiplication Facts Won't Stick: Could a Language/Story Approach Work? A Research Study Examining the Effectiveness of the "Memorize in Minutes" Curriculum

ERIC Educational Resources Information Center

Mahler, Joni D.

2011-01-01

This study examined whether a story/language based method of teaching the multiplication facts would be helpful to students who previously had difficulty with the memorization of those facts. Using the curriculum "Memorize in Minutes" by Alan Walker (Walker, 2000), the researcher taught six fourth-grade students the multiplication facts (3s…

Challenges of German Land Forces 2030 and Beyond

DTIC Science & Technology

2011-03-24

Defense, Army Staff, February 2009 - May 2010). 52 VUCA - volatility, uncertainty, complexity, and ambiguity. Gerras, Stephen J., ed., Strategic...2007). Gerras, Stephen J., ed., Strategic Leadership Primer, 3rd ed. (Carlisle: U.S. Army War College, 2010). Gray, Colin S., Modern Strategy (Oxford...Profession, 2nd rev. and exp. ed. (Boston: Mc Graw Hill Custom Publishing, 2005). Alan G. Stolberg, “Crafting National Interests in the 21st

Use of Commercial Imagery Capabilities in Support of Maritime Domain Awareness

DTIC Science & Technology

2015-06-01

IMAGERY CAPABILITIES IN SUPPORT OF MARITIME DOMAIN AWARENESS by Adam J. Ochs June 2015 Thesis Advisor: Alan D. Scott Second Reader...Paperwork Reduction Project (0704–0188) Washington, DC 20503. 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE June 2015 3. REPORT TYPE AND DATES...Champaign, 2006 Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE IN SPACE SYSTEMS OPERATIONS from the

Localized Density/Drag Prediction for Improved Onboard Orbit Propagation

DTIC Science & Technology

2009-09-01

Localized Density/Drag Prediction for Improved Onboard Orbit Propagation Nathan B. Stastny, Frank R. Chavez, Chin Lin, T. Alan Lovell , Robert A...Terrestrial Physics, Vol. 70, 774-793, 2008 3. Storz, M.F, Bowman, B.R., Branson, J.I., High Accuracy Satellite Drag Model (HASDM), AIAA/ AAS ...Geomagnetic Indices, AIAA/ AAS Astrodynamics Specialist Conference, Honolulu, HI, Aug. 2008 5. Bruinsma, S., Biancale, R., Total Densities Derived from

How localized is ``local?'' Efficiency vs. accuracy of O(N) domain decomposition in local orbital based all-electron electronic structure theory

NASA Astrophysics Data System (ADS)

Havu, Vile; Blum, Volker; Scheffler, Matthias

2007-03-01

Numeric atom-centered local orbitals (NAO) are efficient basis sets for all-electron electronic structure theory. The locality of NAO's can be exploited to render (in principle) all operations of the self-consistency cycle O(N). This is straightforward for 3D integrals using domain decomposition into spatially close subsets of integration points, enabling critical computational savings that are effective from ˜tens of atoms (no significant overhead for smaller systems) and make large systems (100s of atoms) computationally feasible. Using a new all-electron NAO-based code,^1 we investigate the quantitative impact of exploiting this locality on two distinct classes of systems: Large light-element molecules [Alanine-based polypeptide chains (Ala)n], and compact transition metal clusters. Strict NAO locality is achieved by imposing a cutoff potential with an onset radius rc, and exploited by appropriately shaped integration domains (subsets of integration points). Conventional tight rc<= 3å have no measurable accuracy impact in (Ala)n, but introduce inaccuracies of 20-30 meV/atom in Cun. The domain shape impacts the computational effort by only 10-20 % for reasonable rc. ^1 V. Blum, R. Gehrke, P. Havu, V. Havu, M. Scheffler, The FHI Ab Initio Molecular Simulations (aims) Project, Fritz-Haber-Institut, Berlin (2006).

Three Phoma spp. synthesised novel silver nanoparticles that possess excellent antimicrobial efficacy.

PubMed

Rai, Mahendra; Ingle, Avinash P; Gade, Aniket K; Duarte, Marta Cristina Teixeira; Duran, Nelson

2015-10-01

The authors report extracellular mycosynthesis of silver nanoparticles (AgNPs) by Phoma capsulatum, Phoma putaminum and Phoma citri. The AgNPs thus synthesised were characterised by UV-visible spectrophotometer, Fourier transform infrared spectroscopy, Nanosight LM20 and transmission electron microscopy, which confirmed the synthesis of mostly spherical and polydisperse nanoparticles capped with proteins. The size of AgNPs was found in the range of 10-80 , 5-80 and 5-90 nm with an average size of 31.85, 25.43 and 23.29 nm by P. capsulatum, P. putaminum and P. citri, respectively. Further, potential antimicrobial activity was reported against Aspergillus niger, Candida albicans, Salmonella choleraesuis, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. The lowest minimal inhibitory concentration (MIC) (0.85 µg/ml) was reported for AgNPs synthesised from P. citri against S. choleraesuis. However, AgNPs synthesised from P. capsulatum showed the highest MIC (10.62 µg/ml) against S. choleraesuis, P. aeruginosa and E. coli (clinical isolate). The same MIC values (10.62 µg/ml) were also reported against P. aeruginosa and both clinical and standard isolates of E. coli for AgNPs synthesised from P. citri. It was also observed that all the silver nanoparticles showed remarkable antifungal and antibacterial activity against these tested pathogens as compared with the commercially available antifungal and antibacterial agents.

Influence of functional groups on the photophysical properties of dimethylamino chalcones as laser dyes

NASA Astrophysics Data System (ADS)

Ibnaouf, K. H.; Elzupir, A. O.; AlSalhi, M. S.; Alaamer, Abdulaziz S.

2018-02-01

In this report, a series of 3-(4-(Dimethylamino) phenyl)-1-(4,3 di-substituted phenyl)-(2E) - propen -1-one chalcones was synthesised and examined as optical materials. The influence of functional groups (FG) and solvents on their photophysical properties was investigated. These include absorption, fluorescence, Stokes shift, and amplified spontaneous emission (ASE). The absorption spectra of all compounds showed a wavelength band in the range 404-429 nm, whereas the fluorescence spectra exhibited a band at 470-535 nm. We found that the fluorescence intensity was inversely proportional to the concentration of chalcones. The FGs and solvents had an amazing effect on the photophysical properties of the synthesised materials. Unexpectedly, the electron withdrawing group showed a highly red shift, whereas the electron donating group exhibited a blue shift. Further, these compounds showed large Stokes shifts (up to 5800 cm-1). ASE was observed under pump pulse laser excitation, and the wavelengths were tuned from 509 to 566 nm.

Serine is the major residue for ADP-ribosylation upon DNA damage

PubMed Central

Dauben, Helen

2018-01-01

Poly(ADP-ribose) polymerases (PARPs) are a family of enzymes that synthesise ADP-ribosylation (ADPr), a reversible modification of proteins that regulates many different cellular processes. Several mammalian PARPs are known to regulate the DNA damage response, but it is not clear which amino acids in proteins are the primary ADPr targets. Previously, we reported that ARH3 reverses the newly discovered type of ADPr (ADPr on serine residues; Ser-ADPr) and developed tools to analyse this modification (Fontana et al., 2017). Here, we show that Ser-ADPr represents the major fraction of ADPr synthesised after DNA damage in mammalian cells and that globally Ser-ADPr is dependent on HPF1, PARP1 and ARH3. In the absence of HPF1, glutamate/aspartate becomes the main target residues for ADPr. Furthermore, we describe a method for site-specific validation of serine ADP-ribosylated substrates in cells. Our study establishes serine as the primary form of ADPr in DNA damage signalling. PMID:29480802

An alternative hypothesis for high-T 40Ar/39Ar age spectrum discordance in polyphase extraterrestrial materials

NASA Astrophysics Data System (ADS)

Cassata, W. S.; Shuster, D. L.; Renne, P. R.; Weiss, B. P.

2009-12-01

A common feature observed in 40Ar/39Ar age spectra of extraterrestrial (ET) rocks is a conspicuous decrease in the ages of high temperature extractions relative to lower temperature steps and a correlated increase in Ca/K, often succeeded by a monotonic increase in ages. This feature is routinely attributed to recoil-implanted 39Ar from a potassium (K)-rich donor phase into a K-poor receptor phase (e.g., 1,2). While 39Ar recoil redistribution is undoubtedly manifested in many terrestrial and ET 40Ar/39Ar whole-rock age spectra, it cannot easily explain the magnitude of high release temperature 40Ar*/39ArK anomalies observed in Martian meteorites ALH 84001 and Nakhla, as well as other course-grained meteorites and lunar rocks. Depending on the aliquot and sample, 50 - 100% of the pyroxene release spectra in ALH 84001 and Nakhla appear strongly perturbed to lower ages. As the mean recoil distance of 39Ar ~0.1 µm, the recoil hypothesis demands that a high-K phase be ubiquitously distributed amongst sub-micron to micron sized pyroxene crystals to account for the observed pyroxene age spectra. However, in both Nakhla and ALH 84001, pyroxene is often completely isolated from high-K phases and individual grains commonly exceed 100 µm in diameter. 40Ar/39Ar analyses of pyroxene-bearing terrestrial basalts, wherein fine-grained pyroxene and plagioclase are intimately adjoined, show that recoil-implanted 39Ar into pyroxene produces much less precipitous anomalies in 40Ar*/39ArK, as predicted by the recoil lengthscale. An alternative hypothesis is that whole-rock age spectra of ET samples with anomalously low ages at high temperatures may reflect diffusive 40Ar distributions within considerably degassed pyroxene grains. Owing to apparent differences in activation energies between glass and/or plagioclase and pyroxene, 40Ar may diffuse more rapidly from pyroxene under certain high-temperature conditions (i.e., above the temperature at which the extrapolated Ar Arrhenius relationships intersect). Thus, very brief, high-temperature shock-heating events may preferentially degas pyroxene without significantly resetting glass and plagioclase 40Ar/39Ar age spectra. This effect would be enhanced by highly localized shock-heating focused along pyroxene (sub)grain boundaries, as has been inferred in other cases (e.g., 3). The shock and impact origin of this feature may explain its frequent appearance in ET samples, regardless of grain size, as well as the general absence of terrestrial analogs. We will present new 40Ar/39Ar data from Martian meteorites and physical models to distinguish between these competing hypotheses. References Cited: 1. Turner & Cadogan, 1974, Possible effects of 39Ar recoil in 40Ar-39Ar dating. Proc. 5th LPSC, 1601- 1615. 2. Huneke & Smith, 1976, The realities of recoil: 39Ar recoil out of small grains and anomalous age patterns in 40Ar-39Ar dating. Proc. 7th LPSC, 1987-2008. 3. Min et al., 2003, Single grain (U-Th)/He ages from phosphates in Acapulco meteorite and implications for thermal history. EPSL 209, 323-336.

Evolution of the martian mantle as recorded by igneous rocks

NASA Astrophysics Data System (ADS)

Balta, J. B.; McSween, H. Y.

2013-12-01

Martian igneous rocks provide our best window into the current state of the martian mantle and its evolution after accretion and differentiation. Currently, those rocks have been examined in situ by rovers, characterized in general from orbiting spacecraft, and analyzed in terrestrial laboratories when found as meteorites. However, these data have the potential to bias our understanding of martian magmatism, as most of the available meteorites and rover-analyzed rocks come from the Amazonian (<2 Ga) and Hesperian (~3.65 Ga) periods respectively, while igneous rocks from the Noachian (>3.8 Ga) have only been examined by orbiters and as the unique meteorite ALH 84001. After initial differentiation, the main planetary-scale changes in the structure of Mars which impact igneous compositions are cooling of the planet and thickening of the crust with time. As the shergottite meteorites give ages <500 Ma1, they might be expected to represent thick-crust, recent volcanism. Using spacecraft measurements of volcanic compositions and whole rock compositions of meteorites, we demonstrate that the shergottite meteorites do not match the composition of the igneous rocks composing the young volcanoes on Mars, particularly in their silica content, and no crystallization or crustal contamination trend reproduces the volcanoes from a shergottite-like parent magma. However, we show that the shergottite magmas do resemble older martian rocks in composition and mineralogy. The Noachian-aged meteorite ALH 84001 has similar radiogenic-element signatures to the shergottites and may derive from a similar mantle source despite the age difference2. Thus, shergottite-like magmas may represent melting of mantle sources that were much more abundant early in martian history. We propose that the shergottites represent the melting products of an originally-hydrous martian mantle, containing at least several hundred ppm H2O. Dissolved water can increase the silica content of magmas and thus plausibly explains the high silica content of the shergottites. A dehydrating martian mantle with time can explain the decreasing silica contents measured in the young volcanoes and thus fits the measurements from the surface, and producing the high-silica shergottites through a thick crust is difficult without the presence of water. Our model requires that, after differentiation, the martian mantle retained significant water. Much of that water was released early in Mars's history as widespread volcanism allowed for initial dehydration of much of the mantle. The more recent volcanism involved in building the large surface volcanoes was then produced largely from the melting of previously-dehydrated mantle, with possible contributions from crustal rocks and fluids rich in volatiles such as Cl or CO2. Rocks such as the Gusev basalts and the nakhlite and chassignite meteorites also fit into this model and do not require unique circumstances such as a highly-oxidized early martian atmosphere or mantle. Finally, the magmas that eventually became the shergottites were produced when surviving hydrous mantle, similar to that which produced ALH 84001, was entrained in a mantle upwelling such as Tharsis. 1 Nyquist, L. E. et al.. GCA 73, 4288-4309 (2009). 2 Lapen, T. J. et al.. Science 328, 347-351, (2010).

Bringing forward the new generation of alkoxy-thiourea as potential treatment for Acanthamoeba keratitis

NASA Astrophysics Data System (ADS)

Khairul, Wan M.; Goh, Yit-Peng; Daud, Adibah Izzati; Nakisah, M. A.

2017-02-01

Alkoxy substituted thiourea derivatives with general formula of A-ArC(O)NHC(S)NHAr-D which A represents the methoxy group and D denotes -OCnH2n+1 have been successfully synthesised and characterized. In turn, all the synthesised molecules were assayed for anti-amoebic activities towards Acanthamoeba sp to examine the cytotoxicity effect at their IC50 and membrane permeability. As predicted, the findings showed that the synthesised molecules owing promising anti-amoebic activity towards Acanthamoeba sp. To support, the Acridine-orange/Propidium iodide (AOPI) staining result under fluorescence microscopy revealed the treated amoeba cells by these alkoxy thiourea derivatives exhibited loss in their membrane permeability.

Large-Scale Assessments of Students' Learning and Education Policy: Synthesising Evidence across World Regions

ERIC Educational Resources Information Center

Tobin, Mollie; Nugroho, Dita; Lietz, Petra

2016-01-01

This article synthesises findings from two systematic reviews that examined evidence of the link between large-scale assessments (LSAs) and education policy in economically developing countries and in countries of the Asia-Pacific. Analyses summarise evidence of assessment characteristics and policy goals of LSAs that influence education policy,…

Love, Poindexter and Walheim in the A/L prior to EVA 3

NASA Image and Video Library

2008-02-15

S122-E-008894 (15 Feb. 2008) --- Astronaut Alan Poindexter, STS-122 pilot, lends his intravehicular support to the two STS-122 mission specialists assigned to the mission's final spacewalk to perform work on the International Space Station. Equipped with their extravehicular mobility units (EMU) and other gear and just about ready to egress the station and begin the day's external tasks are astronauts Stanley Love (left) and Rex Walheim.

An Exploratory Study of Ram Accelerator Principles

DTIC Science & Technology

1988-10-01

deeply indebted to their students, Carl Knowlen, Alan Kull, Ed Burnham, Kelley Ann Scott, Alfred Alvarez, Dai Murakami, Ivan Stonich, Dean Brackett, Dale...Conference, Honolulu, HI, June 8-10, 1987. 15. D.R. Stull and M. Prophet, project directors, JANAF Thermochemical Tables, U.S. Government Printing...Propulsion, Pergamon Press, New York, 1957. A-2. W.G. Vincenti and C.H. Kruger, Introduction to Physical Gas Dynamics, Wiley, New York, 1965. A-3. D.R. Stull

View of the parachutes of Skylab 3 command module during splashdown

NASA Image and Video Library

1973-08-06

SL3-114-1760 (25 Sept. 1973) --? An excellent view of the three main ring sail parachutes of the Skylab 3 command module as they unfurl during descent to a successful splashdown in the Pacific Ocean. This picture was taken by a hand-held 70mm Hasselblad camera, looking up through a window of the command module. These parachutes open at approximately 10,000 feet altitude. Aboard the CM were astronauts Alan L. Bean, Owen K. Garriott and Jack R. Lousma, who had just completed a 59-day visit to the Skylab space station in Earth orbit. Photo credit: NASA

SKYLAB (SL)-3 CREWMEN - IN-ORBIT PRESS CONFERENCE - JSC

NASA Image and Video Library

1973-09-21

S73-34339 (21 Sept. 1973) --- Astronaut Alan L. Bean, right, Skylab 3 commander, answers a question during the Sept. 21, 1973 press conference from the Skylab space station in Earth orbit. This is a black and white reproduction taken from a television transmission made by a TV camera aboard the Skylab space station. Scientist-astronaut Owen K. Garriott, center, science pilot; and astronaut Jack R. Lousma, left, pilot, await queries from newsmen on the ground to be sent up by scientist-astronaut Story Musgrave, CAPCOM for this shift of Skylab 3. Photo credit: NASA

Synthesis of N-vinylpyrrolidone modified acrylic acid copolymer in supercritical fluids and its application in dental glass-ionomer cements.

PubMed

Moshaverinia, Alireza; Roohpour, Nima; Billington, Richard W; Darr, Jawwad A; Rehman, Ihtesham U

2008-07-01

Compressed fluids such as supercritical CO(2) offer marvellous opportunities for the synthesis of polymers, particularly in applications in medicine and dentistry. It has several advantages in comparison to conventional polymerisation solvents, such as enhanced kinetics and simplified solvent removal process. In this study, poly(acrylic acid-co-itaconic acid-co-N-vinylpyrrolidone) (PAA-IA-NVP), a modified glass-ionomer polymer, was synthesised in supercritical CO(2) (sc-CO(2)) and methanol as a co-solvent. The synthesised polymer was characterized by (1)H-NMR, Raman and FT-IR spectroscopy and viscometry. The molecular weight of the final product was also measured using static light scattering method. The synthesised polymers were subsequently used in several glass ionomer cement formulations (Fuji II commercial GIC) in which mechanical strength (compressive strength (CS), diametral tensile strength (DTS) and biaxial flexural strength (BFS)) and handling properties (working and setting time) of the resulting cements were evaluated. The polymerisation reaction in sc-CO(2)/methanol was significantly faster than the corresponding polymerisation reaction in water and the purification procedures were simpler for the former. Furthermore, glass ionomer cement samples made from the terpolymer prepared in sc-CO(2)/methanol exhibited higher CS and DTS and comparable BFS compared to the same polymer synthesised in water. The working properties of glass ionomer formulations made in sc-CO(2)/methanol were comparable and in selected cases better than the values of those made from polymers synthesised in water.

Skylab (SL)-3 - Astronaut Jack R. Lousma - Utensils

NASA Image and Video Library

1973-09-19

S73-34198 (1 Aug. 1973) --- A close-up view of the hands of astronaut Jack R. Lousma, Skylab 3 pilot, using a silverware utensil to gather food at the food station, in this photographic reproduction taken from a television transmission made by a color TV camera aboard the Skylab space station in Earth orbit. Astronaut Alan L. Bean, commander, had just zoomed the TV camera in for this close-up of the food tray following a series of wide shots of Lousma at the food station. Photo credit: NASA

Astronaut Jack Lousma participates in EVA to deploy twin pole solar shield

NASA Image and Video Library

1973-08-06

SL3-122-2611 (22 Sept. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, participates in the final extravehicular activity (EVA) for that mission, during which a variety of tasks were performed. Here, Bean is near the Apollo Telescope Mount (ATM) during final film change out for the giant telescope facility. Astronaut Owen K. Garriott, who took the picture, is reflected in Bean's helmet visor. The reflected Earth disk in Bean's visor is so clear that the Red Sea and Nile River area can delineated. Photo credit: NASA

Snow covered Alps of France, Italy, and Switzerland

NASA Image and Video Library

1973-07-30

SL3-121-2438 (July-September 1973) --- The Alps of Switzerland, France and Italy are featured in this exceptional photograph taken by a hand-held camera from the Skylab space station during the second manned Skylab mission. Also visible in the out-the-window 70mm Hasselblad view are Lake Geneva, Lake of Lucerne, Rhone River and many other features. The Skylab 3 crewmen, astronauts Alan L. Bean, Owen K. Garriott and Jack R. Lousma completed a 59-day mission with a successful splashdown on Sept. 25, 1973. Photo credit: NASA

Skylab (SL)-3 Crew - Training - Orbital Workshop Trainer - JSC

NASA Image and Video Library

1973-06-16

S73-28419 (16 June 1973) --- The three prime crewmen of the Skylab 3 mission check over flight data during a training session in the crew quarters of the Orbital Workshop (OWS) trainer in the Mission Simulation and Training Facility at the Johnson Space Center (JSC). They are, from left to right, scientist-astronaut Owen K. Garriott, science pilot; and astronauts Alan L. Bean, commander, and Jack R. Lousma, pilot. The 56-day, second manned Skylab Earth-orbital mission is scheduled for liftoff in the latter part of July 1973. Photo credit: NASA

Milestones in welding technology

NASA Astrophysics Data System (ADS)

Dolby, Richard E.

2013-09-01

Sir Alan's PhD thesis describes his research into cracking during arc welding of armour steels. Throughout his career, he had a strong interest in defects of all types, how they formed in metallic structures and how the larger ones could be detected and sized by non-destructive techniques. He was also vitally concerned with how defects impacted on the engineering integrity of welded structures, particularly the risk of fracture in nuclear plant. This study presents a view of some of the major milestones in global welding technology that took place over the 60 or more years of Sir Alan's career and highlights those where he had a personal and direct involvement.

Astronaut Alan Shepard near Lunar Landing Training Vehicle prior to test

NASA Image and Video Library

1970-12-14

S70-56287 (14 Dec. 1970) --- Astronaut Alan B. Shepard Jr., commander of the Apollo 14 lunar landing mission, stands near a Lunar Landing Training Vehicle (LLTV) prior to a test flight at Ellington Air Force Base, Houston, on Dec. 14, 1970. Shepard will be at the controls of the Apollo 14 Lunar Module (LM) when it lands on the moon in the highlands near Fra Mauro. Astronaut Stuart A. Roosa, command module pilot, will remain with the Command and Service Modules (CSM) in lunar orbit while astronauts Shepard and Edgar D. Mitchell, lunar module pilot, descend in the LM to explore the moon.

Revealing the Universe

NASA Astrophysics Data System (ADS)

Cornell, James; Lightman, Alan

1983-05-01

Contributors include Owen Gingerich, Kenneth Bracher, Robert F. C. Vessot, Fred L. Whipple, Fred Franklin, Robert W. Noyes, Robert Rosner, Harvey Tananbaum, Alan P. Lightman, Walter H. G. Lewin, William H. Press, John Huchra, and George B. Field. Alan Lightman, a Fellow of the American Academy of Arts & Sciences since 1996, is adjunct professor of humanities at MIT. He is the author of several books on science, including "Ancient Light: Our Changing View of the Universe" (1991) and "Origins: The Lives and Worlds of Modern Cosmologists" (with R. Brawer, 1990). His works of fiction include "Einstein's Dreams" (1993), "The Diagnosis" (2000), which was a finalist for the National Book Award, and, most recently, "Reunion" (2003).

Alan Stone and the ethics of forensic psychiatry: an overview.

PubMed

Miller, Glenn H

2008-01-01

In 1982, Alan Stone presented a keynote speech at the Annual Meeting of the American Academy of Psychiatry and the Law (AAPL) on the ethics of forensic psychiatry. That speech was sharply critical of the prevailing ethics standards and led forensic psychiatrists to study his ideas carefully. A quarter-century later, he returned to the AAPL's Annual Meeting to present his current thinking. This overview outlines the development of Stone's thought over 25 years and the dialectic among Stone and three critics: Paul Appelbaum, Ezra Griffith, and Stephen Morse. Stone is now more optimistic about the possibility of developing an ethic for forensic psychiatry.

Affordability of Defense Acquisition Programs

DTIC Science & Technology

2015-02-01

I N S T I T U T E F O R D E F E N S E A N A L Y S E S IDA Paper P-5243 Redacted February 2015 Affordability of Defense Acquisition Programs...Gene H. Porter, Project Leader Kathleen M. Conley C. Vance Gordon R . Royce Kneece, Jr. Brian Q. Rieksts Alan H. Shaw David M. Tate INSTITUTE FOR DEFENSE...Kathleen M. Conley C. Vance Gordon R . Royce Kneece, Jr. Brian Q. Rieksts Alan H. Shaw David M. Tate I N S T I T U T E F O R D E F E N S E A N A L Y S E

Light pollution is greatest within migration passage areas for nocturnally-migrating birds around the world.

PubMed

Cabrera-Cruz, Sergio A; Smolinsky, Jaclyn A; Buler, Jeffrey J

2018-02-19

Excessive or misdirected artificial light at night (ALAN) produces light pollution that influences several aspects of the biology and ecology of birds, including disruption of circadian rhythms and disorientation during flight. Many migrating birds traverse large expanses of land twice every year at night when ALAN illuminates the sky. Considering the extensive and increasing encroachment of light pollution around the world, we evaluated the association of the annual mean ALAN intensity over land within the geographic ranges of 298 nocturnally migrating bird species with five factors: phase of annual cycle, mean distance between breeding and non-breeding ranges, range size, global hemisphere of range, and IUCN category of conservation concern. Light pollution within geographic ranges was relatively greater during the migration season, for shorter-distance migrants, for species with smaller ranges, and for species in the western hemisphere. Our results suggest that migratory birds may be subject to the effects of light pollution particularly during migration, the most critical stage in their annual cycle. We hope these results will spur further research on how light pollution affects not only migrating birds, but also other highly mobile animals throughout their annual cycle.

Artificial light at night prolongs juvenile development time in the black field cricket, Teleogryllus commodus.

PubMed

Durrant, Joanna; Botha, L Michael; Green, Mark P; Jones, Therésa M

2018-06-01

A growing body of evidence exists to support a detrimental effect of the presence of artificial light at night (ALAN) on life-history and fitness traits. However, few studies simultaneously investigate multiple traits and the life stages at which changes manifest. We experimentally manipulated ALAN intensities, within those found in the natural environment, to explore the consequences for growth, survival, and reproductive success of the field cricket, Teleogryllus commodus. We reared crickets from egg to adult under a daily light-cycle consisting of 12 hr bright daylight (2,600 lx) followed by either 12 hr darkness (0 lx) or dim-light environments (1, 10, or 100 lx). We found egg hatch, adult survival, and reproductive measures were largely comparable for all treatments. However, juvenile development time (number of days from egg to adult) was on average 10 days (14%) longer and adults were also larger when crickets were exposed to any light at night (1, 10, or 100 lx). Our data demonstrate that chronic lifetime exposure to ALAN can modulate the timing of life-history events and may disrupt phenology to a similar extent as other abiotic factors. © 2018 Wiley Periodicals, Inc.

Searching and synthesising 'grey literature' and 'grey information' in public health: critical reflections on three case studies.

PubMed

Adams, Jean; Hillier-Brown, Frances C; Moore, Helen J; Lake, Amelia A; Araujo-Soares, Vera; White, Martin; Summerbell, Carolyn

2016-09-29

Grey literature includes a range of documents not controlled by commercial publishing organisations. This means that grey literature can be difficult to search and retrieve for evidence synthesis. Much knowledge and evidence in public health, and other fields, accumulates from innovation in practice. This knowledge may not even be of sufficient formality to meet the definition of grey literature. We term this knowledge 'grey information'. Grey information may be even harder to search for and retrieve than grey literature. On three previous occasions, we have attempted to systematically search for and synthesise public health grey literature and information-both to summarise the extent and nature of particular classes of interventions and to synthesise results of evaluations. Here, we briefly describe these three 'case studies' but focus on our post hoc critical reflections on searching for and synthesising grey literature and information garnered from our experiences of these case studies. We believe these reflections will be useful to future researchers working in this area. Issues discussed include search methods, searching efficiency, replicability of searches, data management, data extraction, assessing study 'quality', data synthesis, time and resources, and differentiating evidence synthesis from primary research. Information on applied public health research questions relating to the nature and range of public health interventions, as well as many evaluations of these interventions, may be predominantly, or only, held in grey literature and grey information. Evidence syntheses on these topics need, therefore, to embrace grey literature and information. Many typical systematic review methods for searching, appraising, managing, and synthesising the evidence base can be adapted for use with grey literature and information. Evidence synthesisers should carefully consider the opportunities and problems offered by including grey literature and information. Enhanced incentives for accurate recording and further methodological developments in retrieval will facilitate future syntheses of grey literature and information.

Developing a Mind-Body Exercise Programme for Stressed Children

ERIC Educational Resources Information Center

Wang, Claudia; Seo, Dong-Chul; Geib, Roy W

2017-01-01

Objective: To describe the process of developing a Health Qigong programme for stressed children using a formative evaluation approach. Methods: A multi-step formative evaluation method was utilised. These steps included (1) identifying programme content and drafting the curriculum, (2) synthesising effective and age-appropriate pedagogies, (3)…

Comparative characteristics of Yb:(YLa){sub 2}O{sub 3} laser ceramics

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

Snetkov, I L; Mukhin, I B; Palashov, O V

2016-03-31

Two samples of laser ceramics synthesised at Russian institutes by two different methods are studied. The optical quality of the samples is measured, and efficient (36.6%) lasing in one of the samples is obtained under pumping at a wavelength of 940 nm. (lasers)

Optimizing the synthesis conditions of silver nanoparticles using corn starch and their catalytic reduction of 4-nitrophenol

NASA Astrophysics Data System (ADS)

Salaheldin, Hosam I.

2018-06-01

In this study, silver nanoparticles (SNPs) were synthesised in an aqueous solution of corn starch. To fabricate the SNPs, reaction conditions, such as varying silver nitrate () concentration, time, temperature and solution pH of the reaction, were optimized. Since, the optimum reaction conditions were found 1 mmo l‑1, 15 min and , respectively. Then, to study the role of pH on SNP synthesis, varying pH values of the solution (3, 5, 7, 9 and 11) were investigated. Subsequently, the obtained silver/starch nanocomposites were characterised using different techniques. The x-ray diffraction (XRD) results revealed that the particles were face-centred cubic (FCC), and had an average particle size of 7.5 nm. This was confirmed by high-resolution transmission electron microscopy (HR-TEM) images. Moreover, the synthesised SNPs, at different pH values, were used as nanocatalyst for the reduction of 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride. Under optimum reaction conditions, the higher catalytic activity was obtained with SNPs synthesised at pH 11 compared to lower pH of 7 or 9. Therefore, the rapid, reproducible, cost-effective silver/starch nanocomposite can be widely used for various applications such as drug manufacturing (e.g. analgesics and antipyretics) and the removal of pollutants from wastewater.

Synthesis of gold and silver nanoparticles using Mukia maderaspatna plant extract and its anticancer activity.

PubMed

Devi, Guruviah Karthiga; Sathishkumar, Kannaiyan

2017-03-01

The present investigation reveals the in vitro cytotoxic effect of the biosynthesised metal nanoparticles on the MCF 7 breast cancer cell lines. The gold and silver nanoparticles were synthesised through an environmentally admissible route using the Mukia Maderaspatna plant extract. Initially, the biomolecules present in the plant extract were analysed using phytochemical analysis. Further, these biomolecules reduce the metal ion solution resulting from the formation of metal nanoparticles. The reaction parameters were optimised to control the size of nanoparticles which were confirmed by UV visible spectroscopy. Various instrumental techniques such as Fourier transform-infrared spectroscopy, high resolution transmission electron microscopy, energy dispersive X-ray and scanning electron microscopy were employed to characterise the synthesised gold and silver nanoparticles. The synthesised gold and silver nanoparticles were found to be 20-50 nm and were of different shapes including spherical, triangle and hexagonal. MTT and dual staining assays were carried out with different concentrations (1, 10, 25, 50 and 100 µg/ml) of gold and silver nanoparticles. The results show that the nanoparticles exhibited significant cytotoxic effects with IC 50 value of 44.8 µg/g for gold nanoparticles and 51.3 µg/g for silver nanoparticles. The observations in this study show that this can be developed as a promising nanomaterial in pharmaceutical and healthcare sector.

CM chondrites exhibit the complete petrologic range from type 2 to 1. [Abstract only

NASA Technical Reports Server (NTRS)

Zolensky, M. E.; Browning, L. B.

1994-01-01

Recognition and characterization of the different CM lithologies as components in all meteorites could reveal details of the nature and chronology of alteration and brecciation events on hydrous asteroids. The CM chondrites are of particular interest, as they are the most common carbonaceous chondrites and are found as clasts within other types of meteorites, which suggests that the CM parent asteroids are (or were) widespread in the sections of the asteroid belt providing samples to Earth. Some CM2s, including EET 90047, ALH 83100, and Y 82042, are more 'extensively' altered, and are distinguished by a high proportion of Mg-rich phyllosilicates and Ca-Mg carbonates, frequently in rounded aggregates, and near absence of olivine or pyroxene. 'Completely' altered CMs, called CM1s, essentially lack olivine or pyroxene; these include EET 83334, ALH 88045, and the CM1 clasts in Kaidun. Cold Bokkeveld and EET 84034, both highly brecciated CMs, consist of both extensively and completely altered lithologies. We describe how these lithologies further cosntrain physicochemical conditions on hydrous asteroids. We conclude that CM chondrites exhibit the petrologic range 2 through 1, and that progressive alteration on the parent hydrous asteroid(s) was accompanied by significant increases in temperature (to a peak of approximately 450 C), fO2, water-rock ratio, and (locally) degree of chemical leaching, all well beyond the conditions recorded by CM2s.

The Normativity of the Helping Child--Meta-Ethnographic Perspectives on Individualised Learning in Age-Mixed Classrooms

ERIC Educational Resources Information Center

Huf, Christina; Raggl, Andrea

2017-01-01

This paper discusses possibilities of synthesising ethnographic data. This discussion implies a critical appraisal of the methodology of "Meta-Ethnography." Taking Noblit's and Hare's concept of Meta-Ethnography as a starting point to develop their own practice of synthesising data, the paper suggests to reconsider the possibility to…

Projection multiplex recording of computer-synthesised one-dimensional Fourier holograms for holographic memory systems: mathematical and experimental modelling

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

Betin, A Yu; Bobrinev, V I; Verenikina, N M

A multiplex method of recording computer-synthesised one-dimensional Fourier holograms intended for holographic memory devices is proposed. The method potentially allows increasing the recording density in the previously proposed holographic memory system based on the computer synthesis and projection recording of data page holograms. (holographic memory)

Drug delivery system for an anticancer agent, chlorogenate-Zn/Al-layered double hydroxide nanohybrid synthesised using direct co-precipitation and ion exchange methods

NASA Astrophysics Data System (ADS)

Barahuie, Farahnaz; Hussein, Mohd Zobir; Arulselvan, Palanisamy; Fakurazi, Sharida; Zainal, Zulkarnain

2014-09-01

A nano-structured drug-inorganic clay hybrid involving an active anticancer compound, which is chlorogenic acid (CA) intercalated into Zn/Al-layered double hydroxide, has been assembled via ion-exchange and co-precipitation methods to form a nanohybrid CZAE (a chlorogenic acid-Zn/Al nanohybrid synthesised using an ion-exchange method) and CZAC (a chlorogenic acid-Zn/Al nanohybrid synthesised using a direct method), respectively. The X-ray diffraction (XRD) results confirmed that the CA-LDH had a hybrid structure in which the anionic chlorogenate is arranged between the interlayers as a horizontal monolayer at 90 and 20° angles from the x axis for CZAE and CZAC, respectively. Both nanohybrids have the properties of mesoporous materials. The high loading percentage of chlorogenic acid (approximately 43.2% for CZAE and 45.3% for CZAC) with basal spacings of 11.7 and 12.6 Å for CZAE and CZAC, respectively, corroborates the successful intercalation of chlorogenic acid into the interlayer gallery of layered double hydroxides. Free chlorogenic acid and the synthesised nanocomposites (CZAE, CZAC) were assessed for their cytotoxicity against various cancer cells. The Fourier transform infrared data supported the formation of both nanohybrids, and a thermal analysis showed that the nanohybrids are more thermally stable than their counterparts. The chlorogenate shows a sustained release, and the release rate of chlorogenate from CZAE and CZAC nanohybrids at pH 7.4 is remarkably lower than that at pH 4.8 due to their different release mechanisms. The release rate of chlorogenate from both nanohybrids can be described as pseudo-second order. The present investigation revealed the potential of the nanohybrids to enhance the in vitro anti-tumour effect of chlorogenic acid in liver and lung cancer cells in vitro.

What we have learned about Mars from SNC meteorites

NASA Technical Reports Server (NTRS)

Mcsween, Harry Y., Jr.

1994-01-01

The SNC meteorites are thought to be igneous martian rocks, based on their young crystallization ages and a close match between the composition of gases implanted in them during shock and the atmosphere of Mars. A related meteorite, ALH84001, may be older and thus may represent ancient martian crust. These petrologically diverse basalts and ultramafic rocks are mostly cumulates, but their parent magmas share geochemical and radiogenic isotopic characteristics that suggest they may have formed by remelting the same mantle source region at different times. Information and inferences about martian geology drawn from these samples include the following: Planetary differentiation occured early at approximately 4.5 GA, probably concurrently with accretion. The martian mantle contains different abundances of moderately volatile and siderophile elements and is more Fe-rich than that of the Earth, which has implications for its mineralogy, density, and origin. The estimated core composition has a S abundance near the threshold value for inner core solidification. The former presence of a core dynamo may be suggested by remanent magnetization in Shergottite-Nakhlite-Chassignite (SNC) meteorites, although these rocks may have been magnetized during shock. The mineralogy of martian surface units, inferred from reflectance spectra, matches that of basaltic shergottites, but SNC lithologies thought to have crystallized in the subsurface are not presently recognized. The rheological properties of martian magmas are more accurately derived form these metorites than from observations of martian flow morphology, although the sampled range of magma compositions islimited. Estimates of planetary water abundance and the amount of outgassed water based on these meteorites are contridictory but overlap estimates based on geological observations and atmospheric measurements. Stable isotope measurements indicate that the martian hydrosphere experienced only limited exchange with the lithosphere, but it is in isotopic equilibrium with the atmosphere and has been since 1.3 Ga. The isotopically heavy atmosphere/hydrosphere composition deduced from these rocks reflects a loss process more severe than current atmospheric evolution models, and the occurence of carbonates in SNC meteorites suggest that they, rather than scapolite or hydrous carbonates, are the major crustal sink for CO2. Weathering products in SNC meteorites support the idea of limited alteration of the lithosphere by small volumes of saline, CO2-bearing water. Atmospheric composition and evolution are further constrained by noble gases in these meteorites, although Xe and Kr isotopes suggest different origins for the atmosphere. Planetary ejection of these rocks has promoted an advance in the understanding of impact physics, which has been accomplished by a model involving spallation during large cratering events. Ejection of all the SNC meteorites (except ALH84001) in one or two events may provide a plausible solution to most constraints imposed by chronology, geochemistry, and cosmic ray exposure, although problems remain with this scenario; ALH84001 may represent older martian crust sampled during a separate impact.

Reversible hydrogen storage by NaAlH4 confined within a titanium-functionalized MOF-74(Mg) nanoreactor.

PubMed

Stavila, Vitalie; Bhakta, Raghunandan K; Alam, Todd M; Majzoub, Eric H; Allendorf, Mark D

2012-11-27

We demonstrate that NaAlH(4) confined within the nanopores of a titanium-functionalized metal-organic framework (MOF) template MOF-74(Mg) can reversibly store hydrogen with minimal loss of capacity. Hydride-infiltrated samples were synthesized by melt infiltration, achieving loadings up to 21 wt %. MOF-74(Mg) possesses one-dimensional, 12 Å channels lined with Mg atoms having open coordination sites, which can serve as sites for Ti catalyst stabilization. MOF-74(Mg) is stable under repeated hydrogen desorption and hydride regeneration cycles, allowing it to serve as a "nanoreactor". Confining NaAlH(4) within these pores alters the decomposition pathway by eliminating the stable intermediate Na(3)AlH(6) phase observed during bulk decomposition and proceeding directly to NaH, Al, and H(2), in agreement with theory. The onset of hydrogen desorption for both Ti-doped and undoped nano-NaAlH(4)@MOF-74(Mg) is ∼50 °C, nearly 100 °C lower than bulk NaAlH(4). However, the presence of titanium is not necessary for this increase in desorption kinetics but enables rehydriding to be almost fully reversible. Isothermal kinetic studies indicate that the activation energy for H(2) desorption is reduced from 79.5 kJ mol(-1) in bulk Ti-doped NaAlH(4) to 57.4 kJ mol(-1) for nanoconfined NaAlH(4). The structural properties of nano-NaAlH(4)@MOF-74(Mg) were probed using (23)Na and (27)Al solid-state MAS NMR, which indicates that the hydride is not decomposed during infiltration and that Al is present as tetrahedral AlH(4)(-) anions prior to desorption and as Al metal after desorption. Because of the highly ordered MOF structure and monodisperse pore dimensions, our results allow key template features to be identified to ensure reversible, low-temperature hydrogen storage.

Effects of the supplementation with an high-polyphenols extra-virgin olive oil on kinetic sperm features and seminal plasma oxidative status in healthy dogs.

PubMed

Tufarelli, V; Rizzo, A; Lacalandra, G M; Guaricci, A C; Laudadio, V; Valentini, L

2018-06-01

The aim of this work was to evaluate the effects of the supplementation of two extra-virgin olive oils (EVOO) having different polyphenols content, on canine spermatozoa kinetic parameters and seminal plasma oxidative status. The study was conducted on 12 clinically healthy dogs of different breeds (2-7 years, 5-48 kg of body weight) divided into two groups: an experimental group supplemented with EVOO (Coratina cultivar) high in polyphenols (H-P) and a control group fed EVOO (Cima di Bitonto cultivar) low in polyphenols (L-P). The oil was daily administered per os (1 ml/3 kg BW) before meal. Semen collection was made twice at 15 days distance (D0 1 and D0 2 ) and then at 30 (D30), 60 (D60) and 90 (D90) days. Semen concentration and kinetic parameters were measured using computer-assisted sperm analysis (CASA) system to evaluate: sperm total count, sperm motile (MOT%), progressive motility (PROGR%) and its fractions, straight-line velocity (VSL, μm/s), curvilinear velocity (VCL, μm/s), average path velocity (VAP, μm/s), amplitude of lateral head displacement (ALH, μm), beat cross frequency (BCF, Hz), straightness (STR%) and linearity (LIN%). On seminal plasma, reactive oxygen species (ROS) and biological antioxidant potential (BAP) were tested. From findings, no differences were found for sperm MOT, VSL, VCL, VAP, ALH, BCF, STR, LIN and BAP. A gradual enhancement of PROGR% was observed in H-P group (p < .01). The ROS levels were higher in dogs H-P compared to the other group (p < .05). In conclusion, our results highlight the positive effects of EVOO polyphenols on sperm PROGR% in healthy dogs. © 2018 Blackwell Verlag GmbH.

Nature of Reduced Carbon in Martian Meteorites

NASA Technical Reports Server (NTRS)

Gibson, Everett K., Jr.; McKay, D. S.; Thomas-Keprta, K. L.; Clemett, S. J.; White, L. M.

2012-01-01

Martian meteorites provide important information on the nature of reduced carbon components present on Mars throughout its history. The first in situ analyses for carbon on the surface of Mars by the Viking landers yielded disappointing results. With the recognition of Martian meteorites on Earth, investigations have shown carbon-bearing phases exist on Mars. Studies have yielded presence of reduced carbon, carbonates and inferred graphitic carbon phases. Samples ranging in age from the first approximately 4 Ga of Mars history [e.g. ALH84001] to nakhlites with a crystallization age of 1.3 Ga [e.g. Nakhla] with aqueous alteration processes occurring 0.5-0.7 Ga after crystallizaton. Shergottites demonstrate formation ages around 165-500 Ma with younger aqueous alterations events. Only a limited number of the Martian meteorites do not show evidence of significance terrestrial alterations. Selected areas within ALH84001, Nakhla, Yamato 000593 and possibly Tissint are suitable for study of their indigenous reduced carbon bearing phases. Nakhla possesses discrete, well-defined carbonaceous phases present within iddingsite alteration zones. Based upon both isotopic measurements and analysis of Nakhla's organic phases the presence of pre-terrestrial organics is now recognized. The reduced carbon-bearing phases appear to have been deposited during preterrestrial aqueous alteration events that produced clays. In addition, the microcrystalline layers of Nakhla's iddingsite have discrete units of salt crystals suggestive of evaporation processes. While we can only speculate on the origin of these unique carbonaceous structures, we note that the significance of such observations is that it may allow us to understand the role of Martian carbon as seen in the Martian meteorites with obvious implications for astrobiology and the pre-biotic evolution of Mars. In any case, our observations strongly suggest that reduced organic carbon exists as micrometer- size, discrete structures on Mars associated with clay and salt minerals. The Mars Science Laboratory s investigators should be aware of reduced organic carbon components within clay-bearing phases.