Physiological Characteristics and Production of Folic Acid of Lactobacillus plantarum JA71 Isolated from Jeotgal, a Traditional Korean Fermented Seafood

PubMed Central

Lim, Sang-Dong

2014-01-01

Folic acid, one of the B group of vitamins, is an essential substance for maintaining the functions of the nervous system, and is also known to decrease the level of homocysteine in plasma. Homocysteine influences the lowering of the cognitive function in humans, and especially in elderly people. In order to determine the strains with a strong capacity to produce folic acid, 190 bacteria were isolated from various kinds of jeotgal and chungkuk-jang. In our test experiment, JA71 was found to contain 9.03μg/mL of folic acid after 24 h of incubation in an MRS broth. This showed that JA71 has the highest folic acid production ability compared to the other lactic acid bacteria that were isolated. JA71 was identified as Lactobacillus plantarum by the result of API carbohydrate fermentation pattern and 16s rDNA sequence. JA71 was investigated for its physiological characteristics. The optimum growth temperature of JA71 was 37℃, and the cultures took 12 h to reach pH 4.4. JA71 proved more sensitive to bacitracin when compared with fifteen different antibiotics, and showed most resistance to neomycin and vancomycin. Moreover, it was comparatively tolerant of bile juice and acid, and displayed resistance to Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus with restraint rates of 60.4%, 96.7%, and 76.2%, respectively. These results demonstrate that JA71 could be an excellent strain for application to functional products. PMID:26760752

Application of a JA-Ile Biosynthesis Inhibitor to Methyl Jasmonate-Treated Strawberry Fruit Induces Upregulation of Specific MBW Complex-Related Genes and Accumulation of Proanthocyanidins.

PubMed

Delgado, Laura D; Zúñiga, Paz E; Figueroa, Nicolás E; Pastene, Edgar; Escobar-Sepúlveda, Hugo F; Figueroa, Pablo M; Garrido-Bigotes, Adrián; Figueroa, Carlos R

2018-06-13

Fleshy fruits are an important source of anthocyanins and proanthocyanidins (PAs), which protect plants against stress, and their consumption provides beneficial effects for human health. In strawberry fruit, the application of exogenous methyl jasmonate (MeJA) upregulates anthocyanin accumulation, although the relationship between the jasmonate pathway and anthocyanin and PA biosynthesis in fruits remains to be understood. Anthocyanin and PA accumulation is mainly regulated at the transcriptional level through R2R3-MYB and bHLH transcription factors in different plant species and organs. Here, the effect of jarin-1, a specific inhibitor of bioactive JA (jasmonoyl-isoleucine, JA-Ile) biosynthesis, on anthocyanin and PA accumulation was evaluated during strawberry ( Fragaria × ananassa ) fruit development using an in vitro ripening system for 48 h. Also, we observed the effects of MeJA and the application of jarin-1 to MeJA-treated fruits (MeJA + jarin-1 treatment). We assessed changes of expression levels for the JA-Ile and MeJA biosynthetic ( FaJAR1.2 and FaJMT ), JA signaling-related ( FaMYC2 and FaJAZ1 ), MYB-bHLH-WD40 (MBW) complex-related ( FabHLH3/33 , FaMYB9/10/11 , and repressor FaMYB1 ), and anthocyanin and PA biosynthetic (FaANS , FaUFGT , FaANR , and FaLAR ) genes. In addition, the promoter region of MBW complex-related MYB genes was isolated and sequenced. We found a higher redness of strawberry fruit skin and anthocyanin content in MeJA-treated fruits with respect to jarin-1-treated ones concomitant with an upregulation of FaANS and FaUFGT genes. Inversely, the PA content was higher in jarin-1- and MeJA + jarin-1-treated than in MeJA-treated fruits. MeJA + jarin-1 treatment resulted in an upregulation of FaANR and associated transcription factors such as FabHLH33 and FaMYB9/11 along with FaJMT and FaJAR1.2 . Finally, we found JA-responsive elements in the promoter regions of FaMYB1/9/10/11 genes. It is proposed that PA biosynthesis-related genes

JA, a new type of polyunsaturated fatty acid isolated from Juglans mandshurica Maxim, limits the survival and induces apoptosis of heptocarcinoma cells.

PubMed

Gao, Xiu-Li; Lin, Hua; Zhao, Wei; Hou, Ya-Qin; Bao, Yong-Li; Song, Zhen-Bo; Sun, Lu-Guo; Tian, Shang-Yi; Liu, Biao; Li, Yu-Xin

2016-03-01

Juglans mandshurica Maxim (Juglandaceae) is a famous folk medicine for cancer treatment and some natural compounds isolated from it have been studied extensively. Previously we isolated a type of ω-9 polyunsaturated fatty acid (JA) from the bark of J. mandshurica, however little is known about its activity and the underlying mechanisms. In this study, we studied anti-tumor activity of JA on several human cancer cell lines. Results showed that JA is cytotoxic to HepG2, MDA-MB-231, SGC-7901, A549 and Huh7 cells at a concentration exerting minimal toxic effects on L02 cells. The selective toxicity of JA was better than other classical anti-cancer drugs. Further investigation indicated that JA could induce cell apoptosis, characterized by chromatin condensation, DNA fragmentation and activation of the apoptosis-associated proteins such as Caspase-3 and PARP-1. Moreover, we investigated the cellular apoptosis pathway involved in the apoptosis process in HepG2 cells. We found that proteins involved in mitochondrion (cleaved-Caspase-9, Apaf-1, HtrA2/Omi, Bax, and Mitochondrial Bax) and endocytoplasmic reticulum (XBP-1s, GRP78, cleaved-Caspase-7 and cleaved-Caspase-12) apoptotic pathways were up-regulated when cells were treated by JA. In addition, a morphological change in the mitochondrion was detected. Furthermore, we found that JA could inhibit DNA synthesis and induce G2/M cell cycle arrest. The expression of G2-to-M transition related proteins, such as CyclinB1 and phosphorylated-CDK1, were reduced. In contrast, the G2-to-M inhibitor p21 was increased in JA-treated cells. Overall, our results suggest that JA can induce mitochondrion- and endocytoplasmic reticulum-mediated apoptosis, and G2/M phase arrest in HepG2 cells, making it a promising therapeutic agent against hepatoma.

The tomato res mutant which accumulates JA in roots in non-stressed conditions restores cell structure alterations under salinity.

PubMed

Garcia-Abellan, José O; Fernandez-Garcia, Nieves; Lopez-Berenguer, Carmen; Egea, Isabel; Flores, Francisco B; Angosto, Trinidad; Capel, Juan; Lozano, Rafael; Pineda, Benito; Moreno, Vicente; Olmos, Enrique; Bolarin, Maria C

2015-11-01

Jasmonic acid (JA) regulates a wide spectrum of plant biological processes, from plant development to stress defense responses. The role of JA in plant response to salt stress is scarcely known, and even less known is the specific response in root, the main plant organ responsible for ionic uptake and transport to the shoot. Here we report the characterization of the first tomato (Solanum lycopersicum) mutant, named res (restored cell structure by salinity), that accumulates JA in roots prior to exposure to stress. The res tomato mutant presented remarkable growth inhibition and displayed important morphological alterations and cellular disorganization in roots and leaves under control conditions, while these alterations disappeared when the res mutant plants were grown under salt stress. Reciprocal grafting between res and wild type (WT) (tomato cv. Moneymaker) indicated that the main organ responsible for the development of alterations was the root. The JA-signaling pathway is activated in res roots prior to stress, with transcripts levels being even higher in control condition than in salinity. Future studies on this mutant will provide significant advances in the knowledge of JA role in root in salt-stress tolerance response, as well as in the energy trade-off between plant growth and response to stress. © 2015 Scandinavian Plant Physiology Society.

NtWRKY-R1, a Novel Transcription Factor, Integrates IAA and JA Signal Pathway under Topping Damage Stress in Nicotiana tabacum

PubMed Central

Jin, Weihuan; Zhou, Qi; Wei, Yuanfang; Yang, Jinmiao; Hao, Fengsheng; Cheng, Zhipeng; Guo, Hongxiang; Liu, Weiqun

2018-01-01

Topping damage can induce the nicotine synthesis in tobacco roots, which involves the activation of JA and auxin signal transduction. It remains unclear how these hormone signals are integrated to regulate nicotine synthesis. Here we isolated a transcription factor NtWRKY-R1 from the group IIe of WRKY family and it had strong negative correlation with the expression of putrescine N-methyltransferase, the key enzyme of nicotine synthesis pathway. NtWRKY-R1 was specifically and highly expressed in tobacco roots, and it contains two transcriptional activity domains in the N- and C-terminal. The promoter region of NtWRKY-R1 contains two cis-elements which are responding to JA and auxin signals, respectively. Deletion of NtWRKY-R1 promoter showed that JA and auxin signals were subdued by NtWRKY-R1, and the expression of NtWRKY-R1 was more sensitive to auxin than JA. Furthermore, Yeast two-hybrid experiment demonstrated that NtWRKY-R1 can interact with the actin-binding protein. Our data showed that the intensity of JA and auxin signals can be translated into the expression of NtWRKY-R1, which regulates the balance of actin polymerization and depolymerization through binding actin-binding protein, and then regulates the expression of genes related to nicotine synthesis. The results will help us better understand the function of the WRKY-IIe family in the signaling crosstalk of JA and auxin under damage stress. PMID:29379516

Transcriptome Analysis of ABA/JA-Dual Responsive Genes in Rice Shoot and Root.

PubMed

Kim, Jin-Ae; Bhatnagar, Nikita; Kwon, Soon Jae; Min, Myung Ki; Moon, Seok-Jun; Yoon, In Sun; Kwon, Taek-Ryoun; Kim, Sun Tae; Kim, Beom-Gi

2018-01-01

The phytohormone abscisic acid (ABA) enables plants to adapt to adverse environmental conditions through the modulation of metabolic pathways and of growth and developmental programs. We used comparative microarray analysis to identify genes exhibiting ABA-dependent expression and other hormone-dependent expression among them in Oryza sativa shoot and root. We identified 854 genes as significantly up- or down-regulated in root or shoot under ABA treatment condition. Most of these genes had similar expression profiles in root and shoot under ABA treatment condition, whereas 86 genes displayed opposite expression responses in root and shoot. To examine the crosstalk between ABA and other hormones, we compared the expression profiles of the ABA-dependently regulated genes under several different hormone treatment conditions. Interestingly, around half of the ABA-dependently expressed genes were also regulated by jasmonic acid based on microarray data analysis. We searched the promoter regions of these genes for cis-elements that could be responsible for their responsiveness to both hormones, and found that ABRE and MYC2 elements, among others, were common to the promoters of genes that were regulated by both ABA and JA. These results show that ABA and JA might have common gene expression regulation system and might explain why the JA could function for both abiotic and biotic stress tolerance.

Multiple Reaction Monitoring Mode Based Liquid Chromatography-Mass Spectrometry Method for Simultaneous Quantification of Brassinolide and Other Plant Hormones Involved in Abiotic Stresses.

PubMed

Kasote, Deepak M; Ghosh, Ritesh; Chung, Jun Young; Kim, Jonggeun; Bae, Inhwan; Bae, Hanhong

2016-01-01

Plant hormones are the key regulators of adaptive stress response. Abiotic stresses such as drought and salt are known to affect the growth and productivity of plants. It is well known that the levels of plant hormones such as zeatin (ZA), abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), and brassinolide (BR) fluctuate upon abiotic stress exposure. At present, there is not any single suitable liquid chromatography-mass spectrometry (LC-MS) method for simultaneous analysis of BR and other plant hormones involved in abiotic stresses. In the present study, we developed a simple, sensitive, and rapid method for simultaneous analysis of five major plant hormones, ZA, ABA, JA, SA, and BR, which are directly or indirectly involved in drought and salt stresses. The optimized extraction procedure was simple and easy to use for simultaneous measurement of these plant hormones in Arabidopsis thaliana. The developed method is highly reproducible and can be adapted for simultaneous measurement of changes in plant hormones (ZA, ABA, JA, SA, and BR) in response to abiotic stresses in plants like A. thaliana and tomato.

Integrated metabolomic and proteomic analysis reveals systemic responses of Rubrivivax benzoatilyticus JA2 to aniline stress.

PubMed

Mujahid, Md; Prasuna, M Lakshmi; Sasikala, Ch; Ramana, Ch Venkata

2015-02-06

Aromatic amines are widely distributed in the environment and are major environmental pollutants. Although degradation of aromatic amines is well studied in bacteria, physiological adaptations and stress response to these toxic compounds is not yet fully understood. In the present study, systemic responses of Rubrivivax benzoatilyticus JA2 to aniline stress were deciphered using metabolite and iTRAQ-labeled protein profiling. Strain JA2 tolerated high concentrations of aniline (30 mM) with trace amounts of aniline being transformed to acetanilide. GC-MS metabolite profiling revealed aniline stress phenotype wherein amino acid, carbohydrate, fatty acid, nitrogen metabolisms, and TCA (tricarboxylic acid cycle) were modulated. Strain JA2 responded to aniline by remodeling the proteome, and cellular functions, such as signaling, transcription, translation, stress tolerance, transport and carbohydrate metabolism, were highly modulated. Key adaptive responses, such as transcription/translational changes, molecular chaperones to control protein folding, and efflux pumps implicated in solvent extrusion, were induced in response to aniline stress. Proteo-metabolomics indicated extensive rewiring of metabolism to aniline. TCA cycle and amino acid catabolism were down-regulated while gluconeogenesis and pentose phosphate pathways were up-regulated, leading to the synthesis of extracellular polymeric substances. Furthermore, increased saturated fatty acid ratios in membranes due to aniline stress suggest membrane adaptation. The present study thus indicates that strain JA2 employs multilayered responses: stress response, toxic compound tolerance, energy conservation, and metabolic rearrangements to aniline.

JaK/STAT Inhibition to Prevent Post-Traumatic Epileptogenesis

DTIC Science & Technology

2013-07-31

months 22-28) 2i. Assess mossy fiber sprouting, cell loss and glial proliferation 10 weeks post injury using Timm and Nissl staining (40 mice...1e. Assess protein levels and regional/cellular expression of JaK1 and 2, pSTAT1-5 using fluorescent immunohistochemistry with co- staining for cell...treated with CCI, 10 of which were treated with WP1066. Early post-injury experiments are underway; Timm staining has not revealed mossy fiber

OsMPK3 positively regulates the JA signaling pathway and plant resistance to a chewing herbivore in rice.

PubMed

Wang, Qi; Li, Jiancai; Hu, Lingfei; Zhang, Tongfang; Zhang, Guren; Lou, Yonggen

2013-07-01

KEY MESSAGE : Silencing OsMPK3 decreased elicited JA levels, which subsequently reduced levels of herbivore-induced trypsin protease inhibitors (TrypPIs) and improved the performance of SSB larvae, but did not influence BPH. Mitogen-activated protein kinases (MPKs) are known to play an important role in plant defense by transferring biotic and abiotic signals into programmed cellular responses. However, their functions in the herbivore-induced defense response in rice remain largely unknown. Here, we identified a MPK3 gene from rice, OsMPK3, and found that its expression levels were up-regulated in response to infestation by the larvae of the striped stem borer (SSB) (Chilo suppressalis), to mechanical wounding and to treatment with jasmonic acid (JA), but not to infestation by the brown planthopper (BPH) Nilaparvata lugens or to treatment with salicylic acid. Moreover, mechanical wounding and SSB infestation induced the expression of OsMPK3 strongly and quickly, whereas JA treatment induced the gene more weakly and slowly. Silencing OsMPK3 (ir-mpk3) reduced the expression of the gene by 50-70 %, decreased elicited levels of JA and diminished the expression of a lipoxygenase gene OsHI-LOX and an allene oxide synthase gene OsAOS1. The reduced JA signaling in ir-mpk3 plants decreased the levels of herbivore-induced trypsin protease inhibitors (TrypPIs) and improved the performance of SSB larvae, but did not influence BPH. Our findings suggest that the gene OsMPK3 responds early in herbivore-induced defense and can be regulated by rice plants to activate a specific and appropriate defense response to different herbivores.

Analysis of defense signals in Arabidopsis thaliana leaves by ultra-performance liquid chromatography/tandem mass spectrometry: jasmonates, salicylic acid, abscisic acid.

PubMed

Stingl, Nadja; Krischke, Markus; Fekete, Agnes; Mueller, Martin J

2013-01-01

Defense signaling compounds and phytohormones play an essential role in the regulation of plant responses to various environmental abiotic and biotic stresses. Among the most severe stresses are herbivory, pathogen infection, and drought stress. The major hormones involved in the regulation of these responses are 12-oxo-phytodienoic acid (OPDA), the pro-hormone jasmonic acid (JA) and its biologically active isoleucine conjugate (JA-Ile), salicylic acid (SA), and abscisic acid (ABA). These signaling compounds are present and biologically active at very low concentrations from ng/g to μg/g dry weight. Accurate and sensitive quantification of these signals has made a significant contribution to the understanding of plant stress responses. Ultra-performance liquid chromatography (UPLC) coupled with a tandem quadrupole mass spectrometer (MS/MS) has become an essential technique for the analysis and quantification of these compounds.

Aniline Is an Inducer, and Not a Precursor, for Indole Derivatives in Rubrivivax benzoatilyticus JA2

PubMed Central

Mohammed, Mujahid; Ch, Sasikala; Ch, Ramana V.

2014-01-01

Rubrivivax benzoatilyticus JA2 and other anoxygenic photosynthetic bacteria produce indole derivatives when exposed to aniline, a xenobiotic compound. Though this phenomenon has been reported previously, the role of aniline in the production of indoles is still a biochemical riddle. The present study aims at understanding the specific role of aniline (as precursor or stimulator) in the production of indoles and elucidating the biochemical pathway of indoles in aniline-exposed cells by using stable isotope approaches. Metabolic profiling revealed tryptophan accumulation only in aniline exposed cells along with indole 3-acetic acid (IAA) and indole 3-aldehyde (IAld), the two major catabolites of tryptophan. Deuterium labelled aniline feeding studies revealed that aniline is not a precursor of indoles in strain JA2. Further, production of indoles only in aniline-exposed cells suggests that aniline is an indoles stimulator. In addition, production of indoles depended on the presence of a carbon source, and production enhanced when carbon sources were added to the culture. Isotope labelled fumarate feeding identified, fumarate as the precursor of indole, indicating de novo synthesis of indoles. Glyphosate (shikimate pathway inhibitor) inhibited the indoles production, accumulation of tryptophan, IAA and IAld indicating that indoles synthesis in strain JA2 occurs via the de novo shikimate pathway. The up-regulation of anthranilate synthase gene and induction of anthranilate synthase activity correlated well with tryptophan production in strain JA2. Induction of tryptophan aminotransferase and tryptophan 2-monooxygenase activities corroborated well with IAA levels, suggesting that tryptophan catabolism occurs simultaneously in aniline exposed cells. Our study demonstrates that aniline (stress) stimulates tryptophan/indoles synthesis via the shikimate pathway by possibly modulating the metabolic pathway. PMID:24533057

Aniline is an inducer, and not a precursor, for indole derivatives in Rubrivivax benzoatilyticus JA2.

PubMed

Mujahid, Mohammed; Sasikala, Ch; Ramana, Ch V

2014-01-01

Rubrivivax benzoatilyticus JA2 and other anoxygenic photosynthetic bacteria produce indole derivatives when exposed to aniline, a xenobiotic compound. Though this phenomenon has been reported previously, the role of aniline in the production of indoles is still a biochemical riddle. The present study aims at understanding the specific role of aniline (as precursor or stimulator) in the production of indoles and elucidating the biochemical pathway of indoles in aniline-exposed cells by using stable isotope approaches. Metabolic profiling revealed tryptophan accumulation only in aniline exposed cells along with indole 3-acetic acid (IAA) and indole 3-aldehyde (IAld), the two major catabolites of tryptophan. Deuterium labelled aniline feeding studies revealed that aniline is not a precursor of indoles in strain JA2. Further, production of indoles only in aniline-exposed cells suggests that aniline is an indoles stimulator. In addition, production of indoles depended on the presence of a carbon source, and production enhanced when carbon sources were added to the culture. Isotope labelled fumarate feeding identified, fumarate as the precursor of indole, indicating de novo synthesis of indoles. Glyphosate (shikimate pathway inhibitor) inhibited the indoles production, accumulation of tryptophan, IAA and IAld indicating that indoles synthesis in strain JA2 occurs via the de novo shikimate pathway. The up-regulation of anthranilate synthase gene and induction of anthranilate synthase activity correlated well with tryptophan production in strain JA2. Induction of tryptophan aminotransferase and tryptophan 2-monooxygenase activities corroborated well with IAA levels, suggesting that tryptophan catabolism occurs simultaneously in aniline exposed cells. Our study demonstrates that aniline (stress) stimulates tryptophan/indoles synthesis via the shikimate pathway by possibly modulating the metabolic pathway.

Genome Analysis of the Biotechnologically Relevant Acidophilic Iron Oxidising Strain JA12 Indicates Phylogenetic and Metabolic Diversity within the Novel Genus “Ferrovum”

PubMed Central

Ullrich, Sophie R.; Poehlein, Anja; Tischler, Judith S.; González, Carolina; Ossandon, Francisco J.; Daniel, Rolf; Holmes, David S.; Schlömann, Michael; Mühling, Martin

2016-01-01

Background Members of the genus “Ferrovum” are ubiquitously distributed in acid mine drainage (AMD) waters which are characterised by their high metal and sulfate loads. So far isolation and microbiological characterisation have only been successful for the designated type strain “Ferrovum myxofaciens” P3G. Thus, knowledge about physiological characteristics and the phylogeny of the genus “Ferrovum” is extremely scarce. Objective In order to access the wider genetic pool of the genus “Ferrovum” we sequenced the genome of a “Ferrovum”-containing mixed culture and successfully assembled the almost complete genome sequence of the novel “Ferrovum” strain JA12. Phylogeny and Lifestyle The genome-based phylogenetic analysis indicates that strain JA12 and the type strain represent two distinct “Ferrovum” species. “Ferrovum” strain JA12 is characterised by an unusually small genome in comparison to the type strain and other iron oxidising bacteria. The prediction of nutrient assimilation pathways suggests that “Ferrovum” strain JA12 maintains a chemolithoautotrophic lifestyle utilising carbon dioxide and bicarbonate, ammonium and urea, sulfate, phosphate and ferrous iron as carbon, nitrogen, sulfur, phosphorous and energy sources, respectively. Unique Metabolic Features The potential utilisation of urea by “Ferrovum” strain JA12 is moreover remarkable since it may furthermore represent a strategy among extreme acidophiles to cope with the acidic environment. Unlike other acidophilic chemolithoautotrophs “Ferrovum” strain JA12 exhibits a complete tricarboxylic acid cycle, a metabolic feature shared with the closer related neutrophilic iron oxidisers among the Betaproteobacteria including Sideroxydans lithotrophicus and Thiobacillus denitrificans. Furthermore, the absence of characteristic redox proteins involved in iron oxidation in the well-studied acidophiles Acidithiobacillus ferrooxidans (rusticyanin) and Acidithiobacillus

A liquid chromatography/electrospray ionisation tandem mass spectrometry method for the simultaneous quantification of salicylic, jasmonic and abscisic acids in Coffea arabica leaves.

PubMed

de Sá, Marta; Ferreira, João P; Queiroz, Vagner T; Vilas-Boas, Luís; Silva, Maria C; Almeida, Maria H; Guerra-Guimarães, Leonor; Bronze, Maria R

2014-02-01

Plants have developed an efficient system of recognition that induces a complex network of signalling molecules such as salicylic acid (SA), jasmonic acid (JA) and abscisic acid (ABA) in case of a pathogenic infection. The use of specific and sensitive methods is mandatory for the analysis of compounds in these complex samples. In this study a liquid chromatography/electrospray ionisation tandem mass spectrometry method was developed and validated for the simultaneous quantification of SA, JA and ABA in Coffea arabica (L.) leaves in order to understand the role of these phytohormones in the signalling network involved in the coffee defence response against Hemileia vastatrix. The results showed that the method was specific, linear (r ≥ 0.99) in the range 0.125-1.00 µg mL⁻¹ for JA and ABA and 0.125-5.00 µg mL⁻¹ for SA, and precise (relative standard deviation ≤11%), and the limit of detection (0.010 µg g⁻¹ fresh weight) was adequate for quantifying these phytohormones in this type of matrix. In comparison with healthy leaves, those infected with H. vastatrix (resistance reaction) displayed an increase in SA level 24 h after inoculation, suggesting the involvement of an SA-dependent pathway in coffee resistance. © 2013 Society of Chemical Industry.

New Enhanced Artificial Bee Colony (JA-ABC5) Algorithm with Application for Reactive Power Optimization

PubMed Central

2015-01-01

The standard artificial bee colony (ABC) algorithm involves exploration and exploitation processes which need to be balanced for enhanced performance. This paper proposes a new modified ABC algorithm named JA-ABC5 to enhance convergence speed and improve the ability to reach the global optimum by balancing exploration and exploitation processes. New stages have been proposed at the earlier stages of the algorithm to increase the exploitation process. Besides that, modified mutation equations have also been introduced in the employed and onlooker-bees phases to balance the two processes. The performance of JA-ABC5 has been analyzed on 27 commonly used benchmark functions and tested to optimize the reactive power optimization problem. The performance results have clearly shown that the newly proposed algorithm has outperformed other compared algorithms in terms of convergence speed and global optimum achievement. PMID:25879054

New enhanced artificial bee colony (JA-ABC5) algorithm with application for reactive power optimization.

PubMed

Sulaiman, Noorazliza; Mohamad-Saleh, Junita; Abro, Abdul Ghani

2015-01-01

The standard artificial bee colony (ABC) algorithm involves exploration and exploitation processes which need to be balanced for enhanced performance. This paper proposes a new modified ABC algorithm named JA-ABC5 to enhance convergence speed and improve the ability to reach the global optimum by balancing exploration and exploitation processes. New stages have been proposed at the earlier stages of the algorithm to increase the exploitation process. Besides that, modified mutation equations have also been introduced in the employed and onlooker-bees phases to balance the two processes. The performance of JA-ABC5 has been analyzed on 27 commonly used benchmark functions and tested to optimize the reactive power optimization problem. The performance results have clearly shown that the newly proposed algorithm has outperformed other compared algorithms in terms of convergence speed and global optimum achievement.

Biosynthesis of silver and zinc oxide nanoparticles using Pichia fermentans JA2 and their antimicrobial property

NASA Astrophysics Data System (ADS)

Chauhan, Ritika; Reddy, Arpita; Abraham, Jayanthi

2015-01-01

The development of eco-friendly alternative to chemical synthesis of metal nanoparticles is of great challenge among researchers. The present study aimed to investigate the biological synthesis, characterization, antimicrobial study and synergistic effect of silver and zinc oxide nanoparticles against clinical pathogens using Pichia fermentans JA2. The extracellular biosynthesis of silver and zinc oxide nanoparticles was investigated using Pichia fermentans JA2 isolated from spoiled fruit pulp bought in Vellore local market. The crystalline and stable metallic nanoparticles were characterized evolving several analytical techniques including UV-visible spectrophotometer, X-ray diffraction pattern analysis and FE-scanning electron microscope with EDX-analysis. The biosynthesized metallic nanoparticles were tested for their antimicrobial property against medically important Gram positive, Gram negative and fungal pathogenic microorganisms. Furthermore, the biosynthesized nanoparticles were also evaluated for their increased antimicrobial activities with various commercially available antibiotics against clinical pathogens. The biosynthesized silver nanoparticles inhibited most of the Gram negative clinical pathogens, whereas zinc oxide nanoparticles were able to inhibit only Pseudomonas aeruginosa. The combined effect of standard antibiotic disc and biosynthesized metallic nanoparticles enhanced the inhibitory effect against clinical pathogens. The biological synthesis of silver and zinc oxide nanoparticles is a novel and cost-effective approach over harmful chemical synthesis techniques. The metallic nanoparticles synthesized using Pichia fermentans JA2 possess potent inhibitory effect that offers valuable contribution to pharmaceutical associations.

Monitoring of selected priority and emerging contaminants in the Guadalquivir River and other related surface waters in the province of Jaén, South East Spain.

PubMed

Robles-Molina, José; Gilbert-López, Bienvenida; García-Reyes, Juan F; Molina-Díaz, Antonio

2014-05-01

The province of Jaén counts with four natural parks, numerous rivers, reservoirs and wetlands; moreover, it is probably the region with higher olive oil production in the world, which makes this zone a proper target to be studied based on the European Water Framework Directive 2000/60/CE. The aim of this survey is to monitor a total number of 373 compounds belonging to different families (pesticides, PAHs, nitrosamines, drugs of abuse, pharmaceuticals and life-style compounds) in surface waters located at different points of the province of Jaén. Among these compounds some priority organic substances (regulated by the EU Directive 2008/105/EC) and pollutants of emerging concern (not regulated yet) can be found. A liquid chromatography electrospray time-of-flight mass spectrometry (LC-TOFMS) method covering 340 compounds was developed and applied, together with a gas chromatography triple-quadrupole mass spectrometry (GC-MS/MS) method which enabled the analysis of 63 organic contaminants (30 of these compounds are analyzed by LC-TOFMS as well). From April 2009 to November 2010 a total of 83 surface water samples were collected (rivers, reservoirs and wetlands). In this period numerous organic contaminants were detected, most of them at the ng L(-1) level. The most frequently priority substances found were chlorpyrifos ethyl, diuron and hexachlorobenzene. Within the other groups, the most frequently detected compounds were: terbuthylazine, oxyfluorfen, desethyl terbuthylazine, diphenylamine (pesticide family); fluorene, phenanthrene, pyrene (PAHs group), codeine, paracetamol (pharmaceuticals compounds) and caffeine, nicotine (life-style compounds). As is could be expected, the total concentration of emerging contaminants is distinctly larger than that of priority pollutants, highlighting the importance of continuing with the study of their presence, fate and effects in aquatic environments. However, concentration levels (at the ng per liter level) are low in

Cyclic lipopeptide iturin A structure-dependently induces defense response in Arabidopsis plants by activating SA and JA signaling pathways.

PubMed

Kawagoe, Yumi; Shiraishi, Soma; Kondo, Hiroko; Yamamoto, Shoko; Aoki, Yoshinao; Suzuki, Shunji

2015-05-15

Iturin A is the most well studied antifungal cyclic lipopeptide produced by Bacillus species that are frequently utilized as biological control agents. Iturin A not only shows strong antifungal activity against phytopathogens but also induces defense response in plants, thereby reducing plant disease severity. Here we report the defense signaling pathways triggered by iturin A in Arabidopsis salicylic acid (SA) or jasmonic acid (JA)-insensitive mutants. Iturin A activated the transcription of defense genes PR1 and PDF1.2 through the SA and JA signaling pathways, respectively. The role of iturin A as an elicitor was dependent on the cyclization of the seven amino acids and/or the β-hydroxy fatty acid chain. The iturin A derivative peptide, NH2-(L-Asn)-(D-Tyr)-(D-Asn)-(L-Gln)-(L-Pro)-(D-Asn)-(L-Ser)-COOH, completely suppressed PR1 and PDF1.2 gene expression in wild Arabidopsis plants. The identification of target molecules binding to iturin A and its derivative peptide is expected to shed new light on defense response in plants through the SA and JA signaling pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

Is Watson's ``CHARGE-MODIFIED'' Reduced Mass always best for Diatomic Ions ?

NASA Astrophysics Data System (ADS)

Le Roy, Robert J.; Dattani, Nikesh S.

2016-06-01

Watson's landmark reformulation of the Born-Oppenheimer separation problem has been the basis of most combined-isotopologue analyses of diatomic spectroscopic data since 1980. One noteworthy feature of this work was his proposal that description of the dynamical behaviour of a diatomic ion with (±) charge Q, formed from atoms with isotopic masses of M_1 and M_2, should use a ``charge-modified'' reduced mass: μWat≡ M_1 M_2 /(M_1 + M_2 - Q m_e) , in which m_e is the electron mass, and this proposal seems to have been benignly accepted and adopted. The first quantitative test of this proposal was in the pioneering combined-isotopologue direct-potential-fit (CI-DPF) study of HeH^+ by Coxon and Hajigeorgiou in 1999, where they compared the quality of fit for analyses that used different choices for the definition of the reduced masses of the various isotopologues, and found that the best choice seemed to be to use conventional two-body reduced masses for (M_1 - 1/2 m_e) and (M_2 - 1/2 m_e ). This question was re-examined recently in the context of a CI-DPF study of CH^+, and a rather different conclusion was reached. The present paper combines new CI-DPF studies of HeH^+ and BeH^+ with our recent CH^+ work, and attempts to draw some general conclusions on this matter. J.K.G. Watson, J. Mol. Spectrosc. 80, 411 (1980) J.A. Coxon and P. Hajigeorgiou, J. Mol. Spectrosc. 193, 306 (1999). Y.-S. Cho and R.J. Le Roy, J. Chem. Phys. 144, 024311 (2016)

Deep Sequencing Reveals the Effect of MeJA on Scutellarin Biosynthesis in Erigeron breviscapus

PubMed Central

Xiao, Ying; Zhang, Feng; Chen, Jun-feng; Ji, Qian; Tan, He-Xin; Huang, Xin; Feng, Hao; Huang, Bao-Kang; Chen, Wan-Sheng; Zhang, Lei

2015-01-01

Background Erigeron breviscapus, a well-known traditional Chinese medicinal herb, is broadly used in the treatment of cerebrovascular disease. Scutellarin, a kind of flavonoids, is considered as the material base of the pharmaceutical activities in E. breviscapus. The stable and high content of scutellarin is critical for the quality and efficiency of E. breviscapus in the clinical use. Therefore, understanding the molecular mechanism of scutellarin biosynthesis is crucial for metabolic engineering to increase the content of the active compound. However, there is virtually no study available yet concerning the genetic research of scutellarin biosynthesis in E. breviscapus. Results Using Illumina sequencing technology, we obtained over three billion bases of high-quality sequence data and conducted de novo assembly and annotation without prior genome information. A total of 182,527 unigenes (mean length = 738 bp) were found. 63,059 unigenes were functionally annotated with a cut-off E-value of 10−5. Next, a total of 238 (200 up-regulated and 38 down-regulated genes) and 513 (375 up-regulated and 138 down-regulated genes) differentially expressed genes were identified at different time points after methyl jasmonate (MeJA) treatment, which fell into categories of ‘metabolic process’ and ‘cellular process’ using GO database, suggesting that MeJA-induced activities of signal pathway in plant mainly led to re-programming of metabolism and cell activity. In addition, 13 predicted genes that might participate in the metabolism of flavonoids were found by two co-expression analyses in E. breviscapus. Conclusions Our study is the first to provide a transcriptome sequence resource for E. breviscapus plants after MeJA treatment and it reveals transcriptome re-programming upon elicitation. As the result, several putative unknown genes involved in the metabolism of flavonoids were predicted. These data provide a valuable resource for the genetic and genomic studies of

The Combined Effects of Ethylene and MeJA on Metabolic Profiling of Phenolic Compounds in Catharanthus roseus Revealed by Metabolomics Analysis

PubMed Central

Liu, Jia; Liu, Yang; Wang, Yu; Zhang, Zhong-Hua; Zu, Yuan-Gang; Efferth, Thomas; Tang, Zhong-Hua

2016-01-01

Phenolic compounds belong to a class of secondary metabolites and are implicated in a wide range of responsive mechanisms in plants triggered by both biotic and abiotic elicitors. In this study, we approached the combinational effects of ethylene and MeJA (methyl jasmonate) on phenolic compounds profiles and gene expressions in the medicinal plant Catharanthus roseus. In virtue of a widely non-targeted metabolomics method, we identified a total of 34 kinds of phenolic compounds in the leaves, composed by 7 C6C1-, 11 C6C3-, and 16 C6C3C6 compounds. In addition, 7 kinds of intermediates critical for the biosynthesis of phenolic compounds and alkaloids were identified and discussed with phenolic metabolism. The combinational actions of ethylene and MeJA effectively promoted the total phenolic compounds, especially the C6C1 compounds (such as salicylic acid, benzoic acid) and C6C3 ones (such as cinnamic acid, sinapic acid). In contrast, the C6C3C6 compounds displayed a notably inhibitory trend in this case. Subsequently, the gene-to-metabolite networks were drawn up by searching for correlations between the expression profiles of 5 gene tags and the accumulation profiles of 41 metabolite peaks. Generally, we provide an insight into the controlling mode of ethylene-MeJA combination on phenolic metabolism in C. roseus leaves. PMID:27375495

The Combined Effects of Ethylene and MeJA on Metabolic Profiling of Phenolic Compounds in Catharanthus roseus Revealed by Metabolomics Analysis.

PubMed

Liu, Jia; Liu, Yang; Wang, Yu; Zhang, Zhong-Hua; Zu, Yuan-Gang; Efferth, Thomas; Tang, Zhong-Hua

2016-01-01

Phenolic compounds belong to a class of secondary metabolites and are implicated in a wide range of responsive mechanisms in plants triggered by both biotic and abiotic elicitors. In this study, we approached the combinational effects of ethylene and MeJA (methyl jasmonate) on phenolic compounds profiles and gene expressions in the medicinal plant Catharanthus roseus. In virtue of a widely non-targeted metabolomics method, we identified a total of 34 kinds of phenolic compounds in the leaves, composed by 7 C6C1-, 11 C6C3-, and 16 C6C3C6 compounds. In addition, 7 kinds of intermediates critical for the biosynthesis of phenolic compounds and alkaloids were identified and discussed with phenolic metabolism. The combinational actions of ethylene and MeJA effectively promoted the total phenolic compounds, especially the C6C1 compounds (such as salicylic acid, benzoic acid) and C6C3 ones (such as cinnamic acid, sinapic acid). In contrast, the C6C3C6 compounds displayed a notably inhibitory trend in this case. Subsequently, the gene-to-metabolite networks were drawn up by searching for correlations between the expression profiles of 5 gene tags and the accumulation profiles of 41 metabolite peaks. Generally, we provide an insight into the controlling mode of ethylene-MeJA combination on phenolic metabolism in C. roseus leaves.

Changes in ABA, IAA and JA levels during calyx, fruit and leaves development in cape gooseberry plants (Physalis peruviana L.).

PubMed

Álvarez-Flórez, F; López-Cristoffanini, C; Jáuregui, O; Melgarejo, L M; López-Carbonell, M

2017-06-01

Changes in abscisic acid (ABA), indole-3-acetic acid (IAA) and jasmonic acid (JA) content in developing calyx, fruits and leaves of Physalis peruviana L. plants were analysed. Plant hormones have been widely studied for their roles in the regulation of various aspects related to plant development and, in particular, into their action during development and ripening of fleshly fruits. The obtained evidences suggest that the functions of these hormones are no restricted to a particular development stage, and more than one hormone is involved in controlling various aspects of plant development. Our results will contribute to understand the role of these hormones during growth and development of calyx, fruits and leaves in cape gooseberry plants. This work offers a good, quickly and efficiently protocol to extract and quantify simultaneously ABA, IAA and JA in different tissues of cape gooseberry plants. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Identification of jasmonic acid and its methyl ester as gum-inducing factors in tulips.

PubMed

Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi

2005-02-01

The purpose of this study was to identify endogenous factors that induce gummosis and to show their role in gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) stems. Using procedures to detect endogenous factors that induce gum in the stem of tulips, jasmonic acid (JA) and methyl jasmonate (JA-Me) were successfully identified using gas-liquid chromatography-mass spectrometry. Total amounts of JA and JA-Me designated as jasmonates in tulip stems were also estimated at about 70-80 ng/g fresh weight, using deuterium-labeled jasmonates as internal standards. The application of JA and JA-Me as lanolin pastes substantially induced gums in tulip stems with ethylene production. The application of ethephon, an ethylene-generating compound, however, induced no gummosis although it slightly affected jasmonate content in tulip stems. These results strongly suggest that JA and JA-Me are endogenous factors that induce gummosis in tulip stems.

Mass

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

Quigg, Chris

2007-12-05

In the classical physics we inherited from Isaac Newton, mass does not arise, it simply is. The mass of a classical object is the sum of the masses of its parts. Albert Einstein showed that the mass of a body is a measure of its energy content, inviting us to consider the origins of mass. The protons we accelerate at Fermilab are prime examples of Einsteinian matter: nearly all of their mass arises from stored energy. Missing mass led to the discovery of the noble gases, and a new form of missing mass leads us to the notion of darkmore » matter. Starting with a brief guided tour of the meanings of mass, the colloquium will explore the multiple origins of mass. We will see how far we have come toward understanding mass, and survey the issues that guide our research today.« less

European network for Health Technology Assessment Joint Action (EUnetHTA JA): a process evaluation performed by questionnaires and documentary analysis.

PubMed

Woodford Guegan, Eleanor; Cook, Andrew

2014-06-01

The European network for Health Technology Assessment Joint Action (EUnetHTA JA) project's overarching objective was to 'establish an effective and sustainable HTA [Health technology assessment] collaboration in Europe that brings added value at the regional, national and European level'. Specific objectives were to develop a strategy and business model for sustainable European collaboration on HTA, develop HTA tools and methods and promote good practice in HTA methods and processes. We describe activities performed on behalf of the National Institute for Health Research HTA programme; evaluating the project processes and developing a data set for a registry of planned clinical studies of relevance to public funders. Annual self-completion online questionnaires were sent to project participants and external stakeholders to identify their views about the project processes. Documentary review was undertaken at the project end on the final technical reports from the work packages to examine whether or not their deliverables had been achieved. The project's impact was assessed by whether or not the deliverables were produced, the objectives met and additional 'added value' generated. The project's effectiveness was evaluated by its processes, communication, administration, workings of individual work packages and involvement of external stakeholders. A two-stage Delphi exercise was undertaken to identify the data elements that should be included in a registry of planned clinical studies of relevance to public funders. The data set was validated by an efficacy testing exercise. High response rates were achieved for the questionnaires sent to project participants and this was attributed to the evidence-based strategy implemented. Response rates to questionnaires sent to external stakeholders were disappointingly lower. Most of the high-level objectives were achieved, although applying the developed tools in practice will be implemented in the European network for Health

European network for Health Technology Assessment Joint Action (EUnetHTA JA): a process evaluation performed by questionnaires and documentary analysis.

PubMed Central

Woodford Guegan, Eleanor; Cook, Andrew

2014-01-01

BACKGROUND The European network for Health Technology Assessment Joint Action (EUnetHTA JA) project's overarching objective was to 'establish an effective and sustainable HTA [Health technology assessment] collaboration in Europe that brings added value at the regional, national and European level'. Specific objectives were to develop a strategy and business model for sustainable European collaboration on HTA, develop HTA tools and methods and promote good practice in HTA methods and processes. We describe activities performed on behalf of the National Institute for Health Research HTA programme; evaluating the project processes and developing a data set for a registry of planned clinical studies of relevance to public funders. METHODS Annual self-completion online questionnaires were sent to project participants and external stakeholders to identify their views about the project processes. Documentary review was undertaken at the project end on the final technical reports from the work packages to examine whether or not their deliverables had been achieved. The project's impact was assessed by whether or not the deliverables were produced, the objectives met and additional 'added value' generated. The project's effectiveness was evaluated by its processes, communication, administration, workings of individual work packages and involvement of external stakeholders. A two-stage Delphi exercise was undertaken to identify the data elements that should be included in a registry of planned clinical studies of relevance to public funders. The data set was validated by an efficacy testing exercise. RESULTS AND DISCUSSION High response rates were achieved for the questionnaires sent to project participants and this was attributed to the evidence-based strategy implemented. Response rates to questionnaires sent to external stakeholders were disappointingly lower. Most of the high-level objectives were achieved, although applying the developed tools in practice will be

GA3 and other signal regulators (MeJA and IAA) improve xanthumin biosynthesis in different manners in Xanthium strumarium L.

PubMed

Li, Changfu; Chen, Fangfang; Zhang, Yansheng

2014-08-25

Xanthanolides from Xanthium strumarium L. exhibit various pharmacological activities and these compounds are mainly produced in the glandular trichomes of aerial plant parts. The regulation of xanthanolide biosynthesis has never been reported in the literature. In this study, the effects of phytohormonal stimulation on xanthumin (a xanthanolide compound) biosynthesis, glandular trichomes and germacrene A synthase (GAS) gene expression in X. strumarium L. young leaves were investigated. The exogenous applications of methyl jasmonate (MeJA), indole-3-acetic acid (IAA), and gibberrellin A3 (GA3) at appropriate concentrations were all found to improve xanthumin biosynthesis, but in different ways. It was suggested that a higher gland density stimulated by MeJA (400 µM) or IAA (200 µM) treatment caused at least in part an improvement in xanthumin production, whereas GA3 (10 µM) led to an improvement by up-regulating xanthumin biosynthetic genes within gland cells, not by forming more glandular trichomes. Compared to the plants before the flowering stage, plants that had initiated flowering showed enhanced xanthumin biosynthesis, but no higher gland density, an effect was similar to that caused by exogenous GA3 treatment.

Assessment of iodine nutritional status in the general population in the province of Jaén.

PubMed

Olmedo Carrillo, Pablo; García Fuentes, Eduardo; Gutiérrez Alcántara, Carmen; Serrano Quero, Manuel; Moreno Martínez, Macarena; Ureña Fernández, Tomás; Santiago Fernández, Piedad

2015-10-01

Iodine deficiency affecting both pregnant women and schoolchildren has been reported in Jaén. Iodine deficiency is one of the leading causes of thyroid dysfunction and goiter, and adequate iodine prophylaxis with iodized salt, milk, and dairy products, or iodine supplementation have been shown to significantly improve iodine status in pregnancy. The purpose of this study was to assess iodine nutritional status in the general population of a iodine-deficient area with no previous institutional campaigns of iodine prophylaxis. A descriptive, cross-sectional study. Urinary iodine levels were measured in subjects from the Jaén healthcare district. The data were stratified by sex and age groups, and a survey was conducted on iodized salt consumption. Median and mean urinary iodine levels were 110.59 mcg/L and 130.11 mcg/L respectively. Urinary iodine levels were significantly higher in schoolchildren as compared to other age groups (161.52μg/L vs 109.33μg/L in subjects older than 65 years). Forty-three percent of the population had urinary iodine levels less than 100μg/L, and 68% of women of childbearing age had levels less than 150μg/L. Iodine nutritional status appears to be adequate, but the proportion of the population with urinary iodine levels less than 100μg/L is still very high, and iodized salt consumption is much less common than recommended by the WHO. Copyright © 2015 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

RNA sequencing on Amomum villosum Lour. induced by MeJA identifies the genes of WRKY and terpene synthases involved in terpene biosynthesis.

PubMed

He, Xueying; Wang, Huan; Yang, Jinfen; Deng, Ke; Wang, Teng

2018-02-01

Amomum villosum Lour. is an important Chinese medicinal plant that has diverse medicinal functions, and mainly contains volatile terpenes. This study aims to explore the WRKY transcription factors (TFs) and terpene synthase (TPS) unigenes that might be involved in terpene biosynthesis in A. villosum, and thus providing some new information on the regulation of terpenes in plants. RNA sequencing of A. villosum induced by methyl jasmonate (MeJA) revealed that the WRKY family was the second largest TF family in the transcriptome. Thirty-six complete WRKY domain sequences were expressed in response to MeJA. Further, six WRKY unigenes were highly correlated with eight deduced TPS unigenes. Ultimately, we combined the terpene abundance with the expression of candidate WRKY TFs and TPS unigenes to presume a possible model wherein AvWRKY61, AvWRKY28, and AvWRKY40 might coordinately trans-activate the AvNeoD promoter. We propose an approach to further investigate TF unigenes that might be involved in terpenoid biosynthesis, and identified four unigenes for further analyses.

Negative effective mass in acoustic metamaterial with nonlinear mass-in-mass subsystems

NASA Astrophysics Data System (ADS)

Cveticanin, L.; Zukovic, M.

2017-10-01

In this paper the dynamics of the nonlinear mass-in-mass system as the basic subsystem of the acoustic metamaterial is investigated. The excitation of the system is in the form of the Jacobi elliptic function. The corresponding model to this forcing is the mass-in-mass system with cubic nonlinearity of the Duffing type. Mathematical model of the motion is a system of two coupled strong nonlinear and nonhomogeneous second order differential equations. Particular solution to the system is obtained. The analytical solution of the problem is based on the simple and double integral of the cosine Jacobi function. In the paper the integrals are given in the form of series of trigonometric functions. These results are new one. After some modification the simplified solution in the first approximation is obtained. The result is convenient for discussion. Conditions for elimination of the motion of the mass 1 by connection of the nonlinear dynamic absorber (mass - spring system) are defined. In the consideration the effective mass ratio is introduced in the nonlinear mass-in-mass system. Negative effective mass ratio gives the absorption of vibrations with certain frequencies. The advantage of the nonlinear subunit in comparison to the linear one is that the frequency gap is significantly wider. Nevertheless, it has to be mentioned that the amplitude of vibration differs from zero for a small value. In the paper the analytical results are compared with numerical one and are in agreement.

Pro Memoria. Professor Bolesław Jałowy (1906-1943): Mortui viventes obligant - the livings are obligated to the dead.

PubMed

Wincewicz, Andrzej

2016-01-01

Professor Bolesław Jałowy (1906-1943) was a chairman of Department of Histology and Embryology at Faculty of Medicine of King John Casimir University (Polish: Universytet Jana Kazimierza: UJK) in Lvov. He succeeded Professor Władysław Szymonowicz (1869-1939) who held this position for decades. As the most skillful followers of his tutor, Bolesław Jałowy was a great investigator of physiology of human tissue, embryogenesis, histological consequences of female sex hormones on blood clotting action as well as regeneration of nerves in addition to description of silver staining technique for reticulin fibers of skin. He was a hard working person with gentle attitude to such a subtle matter as microscopic structure of human body. However, he happened to live in brutal conditions of nationalistic struggles. His example shows how much a dedicated scientist could do in a very short time as his life was tragically ended with murdering him during World War Two. His story is a great lesson for generations of academic workers how to meet high moral standards with efficient and creative scientific work in evil and destructive, nationalistic climate that occurs usually in wartime.

The Mass Distribution of Stellar-mass Black Holes

NASA Astrophysics Data System (ADS)

Farr, Will M.; Sravan, Niharika; Cantrell, Andrew; Kreidberg, Laura; Bailyn, Charles D.; Mandel, Ilya; Kalogera, Vicky

2011-11-01

We perform a Bayesian analysis of the mass distribution of stellar-mass black holes using the observed masses of 15 low-mass X-ray binary systems undergoing Roche lobe overflow and 5 high-mass, wind-fed X-ray binary systems. Using Markov Chain Monte Carlo calculations, we model the mass distribution both parametrically—as a power law, exponential, Gaussian, combination of two Gaussians, or log-normal distribution—and non-parametrically—as histograms with varying numbers of bins. We provide confidence bounds on the shape of the mass distribution in the context of each model and compare the models with each other by calculating their relative Bayesian evidence as supported by the measurements, taking into account the number of degrees of freedom of each model. The mass distribution of the low-mass systems is best fit by a power law, while the distribution of the combined sample is best fit by the exponential model. This difference indicates that the low-mass subsample is not consistent with being drawn from the distribution of the combined population. We examine the existence of a "gap" between the most massive neutron stars and the least massive black holes by considering the value, M 1%, of the 1% quantile from each black hole mass distribution as the lower bound of black hole masses. Our analysis generates posterior distributions for M 1%; the best model (the power law) fitted to the low-mass systems has a distribution of lower bounds with M 1%>4.3 M sun with 90% confidence, while the best model (the exponential) fitted to all 20 systems has M 1%>4.5 M sun with 90% confidence. We conclude that our sample of black hole masses provides strong evidence of a gap between the maximum neutron star mass and the lower bound on black hole masses. Our results on the low-mass sample are in qualitative agreement with those of Ozel et al., although our broad model selection analysis more reliably reveals the best-fit quantitative description of the underlying mass

Ultra High Mass Range Mass Spectrometer System

DOEpatents

Reilly, Peter T. A. [Knoxville, TN

2005-12-06

Applicant's present invention comprises mass spectrometer systems that operate in a mass range from 1 to 10.sup.16 DA. The mass spectrometer system comprising an inlet system comprising an aerodynamic lens system, a reverse jet being a gas flux generated in an annulus moving in a reverse direction and a multipole ion guide; a digital ion trap; and a thermal vaporization/ionization detector system. Applicant's present invention further comprises a quadrupole mass spectrometer system comprising an inlet system having a quadrupole mass filter and a thermal vaporization/ionization detector system. Applicant's present invention further comprises an inlet system for use with a mass spectrometer system, a method for slowing energetic particles using an inlet system. Applicant's present invention also comprises a detector device and a method for detecting high mass charged particles.

Mass Defect from Nuclear Physics to Mass Spectral Analysis.

PubMed

Pourshahian, Soheil

2017-09-01

Mass defect is associated with the binding energy of the nucleus. It is a fundamental property of the nucleus and the principle behind nuclear energy. Mass defect has also entered into the mass spectrometry terminology with the availability of high resolution mass spectrometry and has found application in mass spectral analysis. In this application, isobaric masses are differentiated and identified by their mass defect. What is the relationship between nuclear mass defect and mass defect used in mass spectral analysis, and are they the same? Graphical Abstract ᅟ.

Integrated Performance of Next Generation High Data Rate Receiver and AR4JA LDPC Codec for Space Communications

NASA Technical Reports Server (NTRS)

Cheng, Michael K.; Lyubarev, Mark; Nakashima, Michael A.; Andrews, Kenneth S.; Lee, Dennis

2008-01-01

Low-density parity-check (LDPC) codes are the state-of-the-art in forward error correction (FEC) technology that exhibits capacity approaching performance. The Jet Propulsion Laboratory (JPL) has designed a family of LDPC codes that are similar in structure and therefore, leads to a single decoder implementation. The Accumulate-Repeat-by-4-Jagged- Accumulate (AR4JA) code design offers a family of codes with rates 1/2, 2/3, 4/5 and lengths 1024, 4096, 16384 information bits. Performance is less than one dB from capacity for all combinations.Integrating a stand-alone LDPC decoder with a commercial-off-the-shelf (COTS) receiver faces additional challenges than building a single receiver-decoder unit from scratch. In this work, we outline the issues and show that these additional challenges can be over-come by simple solutions. To demonstrate that an LDPC decoder can be made to work seamlessly with a COTS receiver, we interface an AR4JA LDPC decoder developed on a field-programmable gate array (FPGA) with a modern high data rate receiver and mea- sure the combined receiver-decoder performance. Through optimizations that include an improved frame synchronizer and different soft-symbol scaling algorithms, we show that a combined implementation loss of less than one dB is possible and therefore, most of the coding gain evidence in theory can also be obtained in practice. Our techniques can benefit any modem that utilizes an advanced FEC code.

Salicylic acid and jasmonic acid are essential for systemic resistance against tobacco mosaic virus in Nicotiana benthamiana.

PubMed

Zhu, Feng; Xi, De-Hui; Yuan, Shu; Xu, Fei; Zhang, Da-Wei; Lin, Hong-Hui

2014-06-01

Systemic resistance is induced by pathogens and confers protection against a broad range of pathogens. Recent studies have indicated that salicylic acid (SA) derivative methyl salicylate (MeSA) serves as a long-distance phloem-mobile systemic resistance signal in tobacco, Arabidopsis, and potato. However, other experiments indicate that jasmonic acid (JA) is a critical mobile signal. Here, we present evidence suggesting both MeSA and methyl jasmonate (MeJA) are essential for systemic resistance against Tobacco mosaic virus (TMV), possibly acting as the initiating signals for systemic resistance. Foliar application of JA followed by SA triggered the strongest systemic resistance against TMV. Furthermore, we use a virus-induced gene-silencing-based genetics approach to investigate the function of JA and SA biosynthesis or signaling genes in systemic response against TMV infection. Silencing of SA or JA biosynthetic and signaling genes in Nicotiana benthamiana plants increased susceptibility to TMV. Genetic experiments also proved the irreplaceable roles of MeSA and MeJA in systemic resistance response. Systemic resistance was compromised when SA methyl transferase or JA carboxyl methyltransferase, which are required for MeSA and MeJA formation, respectively, were silenced. Moreover, high-performance liquid chromatography-mass spectrometry analysis indicated that JA and MeJA accumulated in phloem exudates of leaves at early stages and SA and MeSA accumulated at later stages, after TMV infection. Our data also indicated that JA and MeJA could regulate MeSA and SA production. Taken together, our results demonstrate that (Me)JA and (Me)SA are required for systemic resistance response against TMV.

An ultrahigh-performance liquid chromatography method with electrospray ionization tandem mass spectrometry for simultaneous quantification of five phytohormones in medicinal plant Glycyrrhiza uralensis under abscisic acid stress.

PubMed

Xiang, Yu; Song, Xiaona; Qiao, Jing; Zang, Yimei; Li, Yanpeng; Liu, Yong; Liu, Chunsheng

2015-07-01

An efficient simplified method was developed to determine multiple classes of phytohormones simultaneously in the medicinal plant Glycyrrhiza uralensis. Ultrahigh-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC/ESI-MS/MS) with multiple reaction monitoring (MRM) in negative mode was used for quantification. The five studied phytohormones are gibberellic acid (GA3), abscisic acid (ABA), jasmonic acid (JA), indole-3-acetic acid, and salicylic acid (SA). Only 100 mg of fresh leaves was needed, with one purification step based on C18 solid-phase extraction. Cinnamic acid was chosen as the internal standard instead of isotope-labeled internal standards. Under the optimized conditions, the five phytohormones with internal standard were separated within 4 min, with good linearities and high sensitivity. The validated method was applied to monitor the spatial and temporal changes of the five phytohormones in G. uralensis under ABA stress. The levels of GA3, ABA, JA, and SA in leaves of G. uralensis were increased at different times and with different tendencies in the reported stress mode. These changes in phytohormone levels are discussed in the context of a possible feedback regulation mechanism. Understanding this mechanism will provide a good chance of revealing the mutual interplay between different biosynthetic routes, which could further help elucidate the mechanisms of effective composition accumulation in medicinal plants.

The Discrepancy between Einstein Mass and Dynamical Mass for SIS and Power-law Mass Models

NASA Astrophysics Data System (ADS)

Li, Rui; Wang, Jiancheng; Shu, Yiping; Xu, Zhaoyi

2018-03-01

We investigate the discrepancy between the two-dimensional projected lensing mass and the dynamical mass for an ensemble of 97 strong gravitational lensing systems discovered by the Sloan Lens ACS Survey, the BOSS Emission-Line Lens Survey (BELLS), and the BELLS for GALaxy-Lyα EmitteR sYstems Survey. We fit the lensing data to obtain the Einstein mass and use the velocity dispersion of the lensing galaxies provided by the Sloan Digital Sky Survey to get the projected dynamical mass within the Einstein radius by assuming the power-law mass approximation. The discrepancy is found to be obvious and quantified by Bayesian analysis. For the singular isothermal sphere mass model, we obtain that the Einstein mass is 20.7% more than the dynamical mass, and the discrepancy increases with the redshift of the lensing galaxies. For the more general power-law mass model, the discrepancy still exists within a 1σ credible region. We suspect the main reason for this discrepancy is mass contamination, including all invisible masses along the line of sight. In addition, the measurement errors and the approximation of the mass models could also contribute to the discrepancy.

Air Mass Considerations in Fog Optical Modeling.

DTIC Science & Technology

1981-02-01

Other microphysical quantities whi.-h are frequently used include the mean radius, the mode radius, and the liquid water content. All these quantities...Commerce .a~ il -’ ecommunications and Commander nr1~nAdministration Ja) Arm~y Comined Arms Center *,Y nn-l t n elecommunication Sciences, & Fort !-eav...Forecasting Selected Weather Variables (Emphasizinq Remote Means )," ASL-TR-O001, January 1978. 73. Heaps, Melvin G., "The 1979 Solar Eclipse and Validation

Using System Mass (SM), Equivalent Mass (EM), Equivalent System Mass (ESM) or Life Cycle Mass (LCM) in Advanced Life Support (ALS) Reporting

NASA Technical Reports Server (NTRS)

Jones, Harry

2003-01-01

The Advanced Life Support (ALS) has used a single number, Equivalent System Mass (ESM), for both reporting progress and technology selection. ESM is the launch mass required to provide a space system. ESM indicates launch cost. ESM alone is inadequate for technology selection, which should include other metrics such as Technology Readiness Level (TRL) and Life Cycle Cost (LCC) and also consider perfom.arxe 2nd risk. ESM has proven difficult to implement as a reporting metric, partly because it includes non-mass technology selection factors. Since it will not be used exclusively for technology selection, a new reporting metric can be made easier to compute and explain. Systems design trades-off performance, cost, and risk, but a risk weighted cost/benefit metric would be too complex to report. Since life support has fixed requirements, different systems usually have roughly equal performance. Risk is important since failure can harm the crew, but it is difficult to treat simply. Cost is not easy to estimate, but preliminary space system cost estimates are usually based on mass, which is better estimated than cost. Amass-based cost estimate, similar to ESM, would be a good single reporting metric. The paper defines and compares four mass-based cost estimates, Equivalent Mass (EM), Equivalent System Mass (ESM), Life Cycle Mass (LCM), and System Mass (SM). EM is traditional in life support and includes mass, volume, power, cooling and logistics. ESM is the specifically defined ALS metric, which adds crew time and possibly other cost factors to EM. LCM is a new metric, a mass-based estimate of LCC measured in mass units. SM includes only the factors of EM that are originally measured in mass, the hardware and logistics mass. All four mass-based metrics usually give similar comparisons. SM is by far the simplest to compute and easiest to explain.

Boundaries of mass resolution in native mass spectrometry.

PubMed

Lössl, Philip; Snijder, Joost; Heck, Albert J R

2014-06-01

Over the last two decades, native mass spectrometry (MS) has emerged as a valuable tool to study intact proteins and noncovalent protein complexes. Studied experimental systems range from small-molecule (drug)-protein interactions, to nanomachineries such as the proteasome and ribosome, to even virus assembly. In native MS, ions attain high m/z values, requiring special mass analyzers for their detection. Depending on the particular mass analyzer used, instrumental mass resolution does often decrease at higher m/z but can still be above a couple of thousand at m/z 5000. However, the mass resolving power obtained on charge states of protein complexes in this m/z region is experimentally found to remain well below the inherent instrument resolution of the mass analyzers employed. Here, we inquire into reasons for this discrepancy and ask how native MS would benefit from higher instrumental mass resolution. To answer this question, we discuss advantages and shortcomings of mass analyzers used to study intact biomolecules and biomolecular complexes in their native state, and we review which other factors determine mass resolving power in native MS analyses. Recent examples from the literature are given to illustrate the current status and limitations.

Aroma changes of black tea prepared from methyl jasmonate treated tea plants*

PubMed Central

Shi, Jiang; Wang, Li; Ma, Cheng-ying; Lv, Hai-peng; Chen, Zong-mao; Lin, Zhi

2014-01-01

Methyl jasmonate (MeJA) was widely applied in promoting food quality. Aroma is one of the key indicators in judging the quality of tea. This study examined the effect of exogenous MeJA treatment on tea aroma. The aroma components in black tea prepared from MeJA-treated fresh tea leaves were extracted using headspace solid-phase microextraction (HS-SPME) and were analyzed using gas chromatography-mass spectrometry (GC-MS) and GC-olfactometry (GC-O). Forty-five volatile compounds were identified. The results revealed that the MeJA-treated black tea had higher levels of terpene alcohols and hexenyl esters than the untreated tea. Moreover, several newly components, including copaene, cubenol, and indole, were induced by the MeJA treatment. The activities of polyphenol oxidase and β-glucosidase in fresh tea leaves changed after the MeJA treatment. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the gene expression levels of polyphenol oxidase and β-primeverosidase were upregulated by two and three folds, respectively, by the MeJA treatment (P<0.01); however, the gene expression of β-glucosidase was downregulated to a half level. In general, the aroma quality of the MeJA-treated black tea was clearly improved. PMID:24711352

Control of Carbon Assimilation and Partitioning by Jasmonate: An Accounting of Growth-Defense Tradeoffs.

PubMed

Havko, Nathan E; Major, Ian T; Jewell, Jeremy B; Attaran, Elham; Browse, John; Howe, Gregg A

2016-01-15

Plant growth is often constrained by the limited availability of resources in the microenvironment. Despite the continuous threat of attack from insect herbivores and pathogens, investment in defense represents a lost opportunity to expand photosynthetic capacity in leaves and absorption of nutrients and water by roots. To mitigate the metabolic expenditure on defense, plants have evolved inducible defense strategies. The plant hormone jasmonate (JA) is a key regulator of many inducible defenses. Synthesis of JA in response to perceived danger leads to the deployment of a variety of defensive structures and compounds, along with a potent inhibition of growth. Genetic studies have established an important role for JA in mediating tradeoffs between growth and defense. However, several gaps remain in understanding of how JA signaling inhibits growth, either through direct transcriptional control of JA-response genes or crosstalk with other signaling pathways. Here, we highlight recent progress in uncovering the role of JA in controlling growth-defense balance and its relationship to resource acquisition and allocation. We also discuss tradeoffs in the context of the ability of JA to promote increased leaf mass per area (LMA), which is a key indicator of leaf construction costs and leaf life span.

Investigation of sodium arsenite, thioacetamide, and diethanolamine in the alkaline comet assay: Part of the JaCVAM comet validation exercise.

PubMed

Beevers, Carol; Henderson, Debbie; Lillford, Lucinda

2015-07-01

As part of the Japanese Center for the Validation of Alternative Methods (JaCVAM)-initiative international validation study of the in vivo rat alkaline comet assay (comet assay), we examined sodium arsenite, thioacetamide, and diethanolamine. Using the JaCVAM approved study protocol version 14.2, each chemical was tested in male rats up to maximum tolerated dose levels and DNA damage in the liver and stomach was assessed approximately 3h after the final administration by gavage. Histopathology assessments of liver and stomach sections from the same animals were also examined for evidence of cytotoxicity or necrosis. No evidence of DNA damage was observed in the stomach of animals treated with sodium arsenite at 7.5, 15, or 30 mg/kg/day. However, equivocal findings were found in the liver, where increases in DNA migration were observed in two independent experiments, but not in all treated animals and not at the same dose levels. Thioacetamide caused an increase in DNA migration in the stomach of rats treated at 19, 38, and 75 mg/kg/day, but not in the liver, despite evidence of marked hepatotoxicity following histopathology assessments. No evidence of DNA damage was observed in the stomach or liver of animals treated with diethanolamine at 175, 350, or 700 mg/kg/day. Copyright © 2015 Elsevier B.V. All rights reserved.

Involvement of nitric oxide in the jasmonate-dependent basal defense against root-knot nematode in tomato plants.

PubMed

Zhou, Jie; Jia, Feifei; Shao, Shujun; Zhang, Huan; Li, Guiping; Xia, Xiaojian; Zhou, Yanhong; Yu, Jingquan; Shi, Kai

2015-01-01

Jasmonic acid (JA) and nitric oxide (NO) are well-characterized signaling molecules in plant defense responses. However, their roles in plant defense against root-knot nematode (RKN, Meloidogyne incognita) infection are largely unknown. In this study, we found that the transcript levels of the JA- and NO-related biosynthetic and signaling component genes were induced after RKN infection. Application of exogenous JA and sodium nitroprusside (SNP; a NO donor) significantly decreased the number of egg masses in tomato roots after RKN infection and partially alleviated RKN-induced decreases in plant fresh weight and net photosynthetic rate. These molecules also alleviated RKN-induced increases in root electrolyte leakage and membrane peroxidation. Importantly, NO scavenger partially inhibited JA-induced RKN defense. The pharmacological inhibition of JA biosynthesis significantly increased the plants' susceptibility to RKNs, which was effectively alleviated by SNP application, showing that NO may be involved in the JA-dependent RKN defense pathway. Furthermore, both JA and SNP induced increases in protease inhibitor 2 (PI2) gene expression after RKN infestation. Silencing of PI2 compromised both JA- and SNP-induced RKN defense responses, suggesting that the PI2 gene mediates JA- and NO-induced defense against RKNs. This work will be important for deepening the understanding of the mechanisms involved in basal defense against RKN attack in plants.

Involvement of nitric oxide in the jasmonate-dependent basal defense against root-knot nematode in tomato plants

PubMed Central

Zhou, Jie; Jia, Feifei; Shao, Shujun; Zhang, Huan; Li, Guiping; Xia, Xiaojian; Zhou, Yanhong; Yu, Jingquan; Shi, Kai

2015-01-01

Jasmonic acid (JA) and nitric oxide (NO) are well-characterized signaling molecules in plant defense responses. However, their roles in plant defense against root-knot nematode (RKN, Meloidogyne incognita) infection are largely unknown. In this study, we found that the transcript levels of the JA- and NO-related biosynthetic and signaling component genes were induced after RKN infection. Application of exogenous JA and sodium nitroprusside (SNP; a NO donor) significantly decreased the number of egg masses in tomato roots after RKN infection and partially alleviated RKN-induced decreases in plant fresh weight and net photosynthetic rate. These molecules also alleviated RKN-induced increases in root electrolyte leakage and membrane peroxidation. Importantly, NO scavenger partially inhibited JA-induced RKN defense. The pharmacological inhibition of JA biosynthesis significantly increased the plants’ susceptibility to RKNs, which was effectively alleviated by SNP application, showing that NO may be involved in the JA-dependent RKN defense pathway. Furthermore, both JA and SNP induced increases in protease inhibitor 2 (PI2) gene expression after RKN infestation. Silencing of PI2 compromised both JA- and SNP-induced RKN defense responses, suggesting that the PI2 gene mediates JA- and NO-induced defense against RKNs. This work will be important for deepening the understanding of the mechanisms involved in basal defense against RKN attack in plants. PMID:25914698

["The madhouse" by W. Kaulbach and the meaning of the picture interpreted by J.A. Schilling, 1863].

PubMed

Rothkopf, A

1980-01-01

This article deals with the picture "Das Narrenhaus" (the Madhouse) by W. Kaulbach and its interpretation by the psychiatrist J.A. Schilling, which he gave in his book "Psychiatrische Briefe" (psychiatric letters) in 1863. This picture is often used as a contemporary document for the situation in the treatment of the mentally ill at the beginning of the last century. The article points out doubts in this procedure. The interpretation by Schilling cannot be considered a document for psychiatric records; on the contrary, it is influenced by contemporary romantic medicine and utilises the picture to exemplify the theoretical concept of culpable human offence as the cause for mental illness.

Mass spectrometry.

NASA Technical Reports Server (NTRS)

Burlingame, A. L.; Johanson, G. A.

1972-01-01

Review of the current state of mass spectrometry, indicating its unique importance for advanced scientific research. Mass spectrometry applications in computer techniques, gas chromatography, ion cyclotron resonance, molecular fragmentation and ionization, and isotope labeling are covered. Details are given on mass spectrometry applications in bio-organic chemistry and biomedical research. As the subjects of these applications are indicated alkaloids, carbohydrates, lipids, terpenes, quinones, nucleic acid components, peptides, antibiotics, and human and animal metabolisms. Particular attention is given to the mass spectra of organo-inorganic compounds, inorganic mass spectrometry, surface phenomena such as secondary ion and electron emission, and elemental and isotope analysis. Further topics include mass spectrometry in organic geochemistry, applications in geochronology and cosmochemistry, and organic mass spectrometry.

Jasmonoyl-l-Isoleucine Coordinates Metabolic Networks Required for Anthesis and Floral Attractant Emission in Wild Tobacco (Nicotiana attenuata)[C][W][OPEN

PubMed Central

Stitz, Michael; Hartl, Markus; Baldwin, Ian T.; Gaquerel, Emmanuel

2014-01-01

Jasmonic acid and its derivatives (jasmonates [JAs]) play central roles in floral development and maturation. The binding of jasmonoyl-l-isoleucine (JA-Ile) to the F-box of CORONATINE INSENSITIVE1 (COI1) is required for many JA-dependent physiological responses, but its role in anthesis and pollinator attraction traits remains largely unexplored. Here, we used the wild tobacco Nicotiana attenuata, which develops sympetalous flowers with complex pollination biology, to examine the coordinating function of JA homeostasis in the distinct metabolic processes that underlie flower maturation, opening, and advertisement to pollinators. From combined transcriptomic, targeted metabolic, and allometric analyses of transgenic N. attenuata plants for which signaling deficiencies were complemented with methyl jasmonate, JA-Ile, and its functional homolog, coronatine (COR), we demonstrate that (1) JA-Ile/COR-based signaling regulates corolla limb opening and a JA-negative feedback loop; (2) production of floral volatiles (night emissions of benzylacetone) and nectar requires JA-Ile/COR perception through COI1; and (3) limb expansion involves JA-Ile-induced changes in limb fresh mass and carbohydrate metabolism. These findings demonstrate a master regulatory function of the JA-Ile/COI1 duet for the main function of a sympetalous corolla, that of advertising for and rewarding pollinator services. Flower opening, by contrast, requires JA-Ile signaling-dependent changes in primary metabolism, which are not compromised in the COI1-silenced RNA interference line used in this study. PMID:25326292

Risk of malnutrition (over and under-nutrition): validation of the JaNuS screening tool.

PubMed

Donini, Lorenzo M; Ricciardi, Laura Maria; Neri, Barbara; Lenzi, Andrea; Marchesini, Giulio

2014-12-01

Malnutrition (over and under-nutrition) is highly prevalent in patients admitted to hospital and it is a well-known risk factor for increased morbidity and mortality. Nutritional problems are often misdiagnosed, and especially the coexistence of over and undernutrition is not usually recognized. We aimed to develop and validate a screening tool for the easy detection and reporting of both undernutrition and overnutrition, specifically identifying the clinical conditions where the two types of malnutrition coexist. The study consisted of three phases: 1) selection of an appropriate study population (estimation sample) and of the hospital admission parameters to identify overnutrition and undernutrition; 2) combination of selected variables to create a screening tool to assess the nutritional risk in case of undernutrition, overnutrition, or the copresence of both the conditions, to be used by non-specialist health care professionals; 3) validation of the screening tool in a different patient sample (validation sample). Two groups of variables (12 for undernutrition, 7 for overnutrition) were identified in separate logistic models for their correlation with the outcome variables. Both models showed high efficacy, sensitivity and specificity (overnutrition, 97.7%, 99.6%, 66.6%, respectively; undernutrition, 84.4%, 83.6%, 84.8%). The logistic models were used to construct a two-faced test (named JaNuS - Just A Nutritional Screening) fitting into a two-dimension Cartesian coordinate graphic system. In the validation sample the JaNuS test confirmed its predictive value. Internal consistency and test-retest analysis provide evidence for the reliability of the test. The study provides a screening tool for the assessment of the nutritional risk, based on parameters easy-to-use by health care personnel lacking nutritional competence and characterized by excellent predictive validity. The test might be confidently applied in the clinical setting to determine the importance of

Neutrino phenomenology, dark energy and leptogenesis from pseudo-Nambu Goldstone bosons

NASA Astrophysics Data System (ADS)

Hill, C. T.; Mocioiu, I.; Paschos, E. A.; Sarkar, U.

2007-07-01

We consider a model of dynamical neutrino masses via the see-saw mechanism. Nambu-Goldstone bosons (majorons) arise associated with the formation of the heavy right-handed Majorana masses. These bosons then acquire naturally soft masses (become pNGB's) at loop level via the Higgs-Yukawa mass terms. These models, like the original neutrino pNGB quintessence schemes of the 1980's [C.T. Hill, D.N. Schramm, J.N. Fry, Nucl. Part. Phys. 19 (1989) 25; J.A. Frieman, C.T. Hill, R. Watkins, Phys. Rev. D 46 (1992) 1226; A.K. Gupta, C.T. Hill, R. Holman, E.W. Kolb, Phys. Rev. D 45 (1992) 441; J.A. Frieman, C.T. Hill, A. Stebbins, I. Waga, Phys. Rev. Lett. 75 (1995) 2077, astro-ph/9505060] that proceed through the Dirac masses, are natural, have cosmological implications through mass varying neutrinos, long range forces, and provide a soft potential for dark energy. We further argue that these models can explain leptogenesis naturally through the decays of the right-handed neutrinos.

Measuring masses of large biomolecules and bioparticles using mass spectrometric techniques.

PubMed

Peng, Wen-Ping; Chou, Szu-Wei; Patil, Avinash A

2014-07-21

Large biomolecules and bioparticles play a vital role in biology, chemistry, biomedical science and physics. Mass is a critical parameter for the characterization of large biomolecules and bioparticles. To achieve mass analysis, choosing a suitable ion source is the first step and the instruments for detecting ions, mass analyzers and detectors should also be considered. Abundant mass spectrometric techniques have been proposed to determine the masses of large biomolecules and bioparticles and these techniques can be divided into two categories. The first category measures the mass (or size) of intact particles, including single particle quadrupole ion trap mass spectrometry, cell mass spectrometry, charge detection mass spectrometry and differential mobility mass analysis; the second category aims to measure the mass and tandem mass of biomolecular ions, including quadrupole ion trap mass spectrometry, time-of-flight mass spectrometry, quadrupole orthogonal time-of-flight mass spectrometry and orbitrap mass spectrometry. Moreover, algorithms for the mass and stoichiometry assignment of electrospray mass spectra are developed to obtain accurate structure information and subunit combinations.

Changes in the Polypeptide Patterns of Barley Seedlings Exposed to Jasmonic Acid and Salinity 1

PubMed Central

Maslenkova, Liliana Todorova; Miteva, Tania Simeonova; Popova, Losanka P.

1992-01-01

Soluble and thylakoid membrane proteins of jasmonic acid (JA)-treated and salt-stressed barley (Hordeum vulgare L.) seedlings were investigated using 15% sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis. High JA concentrations induced marked quantitative and qualitative changes in polypeptide profiles concerning mainly the proteins with approximately equal mobility, as in NaCl-stressed plants. The most obvious increase in thylakoid polypeptide band intensity was at 55 to 57 kilodaltons (kD). The relative share of some polypeptides with apparent molecular masses above 66 kD and of polypeptides with lower molecular masses in the region of 20.5 to 15 kD was enhanced. At the same time, one new band at 31 to 31.5 kD was well expressed at 25 and 250 micromolar JA concentrations and became discernible in the 100 micromolar NaCl-treated plants. The intensity of some polypeptides of soluble proteins (molecular masses of 60, 47, 37, 30, and 23.4 kD) increased with increasing JA concentration, whereas the intensities of other polypeptide bands (55, 21.4, and 15 kD) decreased. Enhanced levels of 60-, 47-, 34-, and 30-kD polypeptides and reduced levels of 55- and 15-kD polypeptides were present in NaCl-treated plants. The appearance of one new polypeptide, of 25.1 kD, was observed only in NaCl-treated plants. At 100 millimolar NaCl, an eightfold increase in proline content was observed while at 250 micromolar JA, the proline content was threefold over the control. It is hypothesized that exogenously applied jasmonates act as stress agents. As such, they provoke alterations in the proline content and they can modulate typical stress responses by induction of stress proteins. ImagesFigure 1Figure 4Figure 5 PMID:16668698

Jasmonic acid protects etiolated seedlings of Arabidopsis thaliana against herbivorous arthropods

PubMed Central

Boex-Fontvieille, Edouard; Rustgi, Sachin; Von Wettstein, Diter; Pollmann, Stephan; Reinbothe, Steffen; Reinbothe, Christiane

2016-01-01

ABSTRACT Seed predators can cause mass ingestion of larger seed populations. As well, herbivorous arthropods attempt to attack etiolated seedlings and chose the apical hook for ingestion, aimed at dropping the cotyledons for later consumption. Etiolated seedlings, as we show here, have established an efficient mechanism of protecting their Achilles' heel against these predators, however. Evidence is provided for a role of jasmonic acid (JA) in this largely uncharacterized plant-herbivore interaction during skotomorphogenesis and that this comprises the temporally and spatially tightly controlled synthesis of a cysteine protease inhibitors of the Kunitz family. Interestingly, the same Kunitz protease inhibitor was found to be expressed in flowers of Arabidopsis where endogenous JA levels are high for fertility. Because both the apical hook and inflorescences were preferred isopod targets in JA-deficient plants that could be rescued by exogenously administered JA, our data identify a JA-dependent mechanism of plant arthropod deterrence that is recalled in different organs and at quite different times of plant development. PMID:27485473

Mass loss

NASA Technical Reports Server (NTRS)

Goldberg, Leo

1987-01-01

Observational evidence for mass loss from cool stars is reviewed. Spectra line profiles are used for the derivation of mass-loss rates with the aid of the equation of continuity. This equation implies steady mass loss with spherical symmetry. Data from binary stars, Mira variables, and red giants in globular clusters are examined. Silicate emission is discussed as a useful indicator of mass loss in the middle infrared spectra. The use of thermal millimeter-wave radiation, Very Large Array (VLA) measurement of radio emission, and OH/IR masers are discussed as a tool for mass loss measurement. Evidence for nonsteady mass loss is also reviewed.

Buoyancy contribution to uncertainty of mass, conventional mass and force

NASA Astrophysics Data System (ADS)

Malengo, Andrea; Bich, Walter

2016-04-01

The conventional mass is a useful concept introduced to reduce the impact of the buoyancy correction in everyday mass measurements, thus avoiding in most cases its accurate determination, necessary in measurements of ‘true’ mass. Although usage of conventional mass is universal and standardized, the concept is considered as a sort of second-choice tool, to be avoided in high-accuracy applications. In this paper we show that this is a false belief, by elucidating the role played by covariances between volume and mass and between volume and conventional mass at the various stages of the dissemination chain and in the relationship between the uncertainties of mass and conventional mass. We arrive at somewhat counter-intuitive results: the volume of the transfer standard plays a comparatively minor role in the uncertainty budget of the standard under calibration. In addition, conventional mass is preferable to mass in normal, in-air operation, as its uncertainty is smaller than that of mass, if covariance terms are properly taken into account, and the uncertainty over-stating (typically) resulting from neglecting them is less severe than that (always) occurring with mass. The same considerations hold for force. In this respect, we show that the associated uncertainty is the same using mass or conventional mass, and, again, that the latter is preferable if covariance terms are neglected.

Prebiotic potential of Jerusalem artichoke (Helianthus tuberosus L.) in Wistar rats: effects of levels of supplementation on hindgut fermentation, intestinal morphology, blood metabolites and immune response.

PubMed

Samal, Lipismita; Chaturvedi, Vishwa Bandhu; Saikumar, Guttula; Somvanshi, Ramesh; Pattanaik, Ashok Kumar

2015-06-01

Many studies have been conducted using purified prebiotics such as inulin or fructooligosaccharides (FOS) as nutraceuticals, but there is very little information available on the prebiotic potential of raw products rich in inulin and FOS, such as Jerusalem artichoke (JA; Helianthus tuberosus L.). The present experiment aimed to evaluate the prebiotic effects of JA tubers in rats. Seventy-two Wistar weanling rats divided into four groups were fed for 12 weeks on a basal diet fortified with pulverized JA tubers at 0 (control), 20, 40 and 60 g kg(-1) levels. Enhanced cell-mediated immunity in terms of skin indurations (P = 0.082) and CD4+ T-lymphocyte population (P = 0.002) was observed in the JA-supplemented groups compared with the control group. Blood haemoglobin (P = 0.017), glucose (P = 0.001), urea (P = 0.004) and calcium (P = 0.048) varied favourably upon inclusion of JA. An increasing trend (P = 0.059) in the length of large intestine was apparent in the JA-fed groups. The tissue mass of caecum (P = 0.069) and colon (P = 0.003) was increased in the JA-supplemented groups, accompanied by higher (P = 0.007) caecal crypt depth. The pH and ammonia concentrations of intestinal digesta decreased and those of lactate and total volatile fatty acids increased in the JA-fed groups. The results suggest that JA had beneficial effects on immunity, blood metabolites, intestinal morphometry and hindgut fermentation of rats. © 2014 Society of Chemical Industry.

Control of Carbon Assimilation and Partitioning by Jasmonate: An Accounting of Growth–Defense Tradeoffs

PubMed Central

Havko, Nathan E.; Major, Ian T.; Jewell, Jeremy B.; Attaran, Elham; Browse, John; Howe, Gregg A.

2016-01-01

Plant growth is often constrained by the limited availability of resources in the microenvironment. Despite the continuous threat of attack from insect herbivores and pathogens, investment in defense represents a lost opportunity to expand photosynthetic capacity in leaves and absorption of nutrients and water by roots. To mitigate the metabolic expenditure on defense, plants have evolved inducible defense strategies. The plant hormone jasmonate (JA) is a key regulator of many inducible defenses. Synthesis of JA in response to perceived danger leads to the deployment of a variety of defensive structures and compounds, along with a potent inhibition of growth. Genetic studies have established an important role for JA in mediating tradeoffs between growth and defense. However, several gaps remain in understanding of how JA signaling inhibits growth, either through direct transcriptional control of JA-response genes or crosstalk with other signaling pathways. Here, we highlight recent progress in uncovering the role of JA in controlling growth-defense balance and its relationship to resource acquisition and allocation. We also discuss tradeoffs in the context of the ability of JA to promote increased leaf mass per area (LMA), which is a key indicator of leaf construction costs and leaf life span. PMID:27135227

Relationship between body mass, lean mass, fat mass, and limb bone cross-sectional geometry: Implications for estimating body mass and physique from the skeleton.

PubMed

Pomeroy, Emma; Macintosh, Alison; Wells, Jonathan C K; Cole, Tim J; Stock, Jay T

2018-05-01

Estimating body mass from skeletal dimensions is widely practiced, but methods for estimating its components (lean and fat mass) are poorly developed. The ability to estimate these characteristics would offer new insights into the evolution of body composition and its variation relative to past and present health. This study investigates the potential of long bone cross-sectional properties as predictors of body, lean, and fat mass. Humerus, femur and tibia midshaft cross-sectional properties were measured by peripheral quantitative computed tomography in sample of young adult women (n = 105) characterized by a range of activity levels. Body composition was estimated from bioimpedance analysis. Lean mass correlated most strongly with both upper and lower limb bone properties (r values up to 0.74), while fat mass showed weak correlations (r ≤ 0.29). Estimation equations generated from tibial midshaft properties indicated that lean mass could be estimated relatively reliably, with some improvement using logged data and including bone length in the models (minimum standard error of estimate = 8.9%). Body mass prediction was less reliable and fat mass only poorly predicted (standard errors of estimate ≥11.9% and >33%, respectively). Lean mass can be predicted more reliably than body mass from limb bone cross-sectional properties. The results highlight the potential for studying evolutionary trends in lean mass from skeletal remains, and have implications for understanding the relationship between bone morphology and body mass or composition. © 2018 The Authors. American Journal of Physical Anthropology Published by Wiley Periodicals, Inc.

Alienation, Mass Society and Mass Culture.

ERIC Educational Resources Information Center

Dam, Hari N.

This monograph examines the nature of alienation in mass society and mass culture. Conceptually based on the "Gemeinschaft-Gesellschaft" paradigm of sociologist Ferdinand Tonnies, discussion traces the concept of alienation as it appears in the philosophies of Hegel, Marx, Kierkegaard, Sartre, and others. Dwight Macdonald's "A Theory of Mass…

Laser-based mass spectrometry for in situ chemical composition analysis of planetary surfaces

NASA Astrophysics Data System (ADS)

Frey, Samira; Neuland, Maike B.; Grimaudo, Valentine; Moreno-García, Pavel; Riedo, Andreas; Tulej, Marek; Broekmann, Peter; Wurz, Peter

2016-04-01

Mass spectrometry is an important analytical technique in space research. The chemical composition of planetary surface material is a key scientific question on every space mission to a planet, moon or asteroid. Chemical composition measurements of rocky material on the surface are of great importance to understand the origin and evolution of the planetary body.[1] A miniature laser ablation/ionisation reflectron- type time-of-flight mass spectrometer (instrument name LMS) was designed and built at the University of Bern for planetary research.[2] Despite its small size and light weight, the LMS instrument still maintains the same capabilities as large laboratory systems, which makes it suitable for its application on planetary space missions.[3-5] The high dynamic range of about eight orders of magnitude, high lateral (μm-level) and vertical (sub-nm level) resolution and high detection sensitivity for almost all elements (10 ppb, atomic fraction) make LMS a versatile instrument for various applications. LMS is a suitable instrument for in situ measurements of elemental and isotope composition with high precision and accuracy. Measurements of Pb- isotope abundances can be used for dating of planetary material. Measurements of bio-relevant elements allow searching for past or present life on a planetary surface. The high spatial resolution, both in lateral and vertical direction, is of considerable interest, e.g. for analysis of inhomogeneous, extraterrestrial samples as well as weathering processes of planetary material. References [1] P. Wurz, D. Abplanalp, M. Tulej, M. Iakovleva, V.A. Fernandes, A. Chumikov, and G. Managadze, "Mass Spectrometric Analysis in Planetary Science: Investigation of the Surface and the Atmosphere", Sol. Sys. Res., 2012, 46, 408. [2] U. Rohner, J.A. Whitby, P. Wurz, "A miniature laser ablation time of flight mass spectrometer for in situ planetary exploration" Meas. Sci. Tch., 2003, 14, 2159. [3] M. Tulej, A. Riedo, M.B. Neuland, S

ON THE MASS DISTRIBUTION AND BIRTH MASSES OF NEUTRON STARS

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

Oezel, Feryal; Psaltis, Dimitrios; Santos Villarreal, Antonio

We investigate the distribution of neutron star masses in different populations of binaries, employing Bayesian statistical techniques. In particular, we explore the differences in neutron star masses between sources that have experienced distinct evolutionary paths and accretion episodes. We find that the distribution of neutron star masses in non-recycled eclipsing high-mass binaries as well as of slow pulsars, which are all believed to be near their birth masses, has a mean of 1.28 M{sub Sun} and a dispersion of 0.24 M{sub Sun }. These values are consistent with expectations for neutron star formation in core-collapse supernovae. On the other hand,more » double neutron stars, which are also believed to be near their birth masses, have a much narrower mass distribution, peaking at 1.33 M{sub Sun }, but with a dispersion of only 0.05 M{sub Sun }. Such a small dispersion cannot easily be understood and perhaps points to a particular and rare formation channel. The mass distribution of neutron stars that have been recycled has a mean of 1.48 M{sub Sun} and a dispersion of 0.2 M{sub Sun }, consistent with the expectation that they have experienced extended mass accretion episodes. The fact that only a very small fraction of recycled neutron stars in the inferred distribution have masses that exceed {approx}2 M{sub Sun} suggests that only a few of these neutron stars cross the mass threshold to form low-mass black holes.« less

Macro-microscopic mass formulae and nuclear mass predictions

NASA Astrophysics Data System (ADS)

Royer, G.; Guilbaud, M.; Onillon, A.

2010-12-01

Different mass formulae derived from the liquid drop model and the pairing and shell energies of the Thomas-Fermi model have been studied and compared. They include or not the diffuseness correction to the Coulomb energy, the charge exchange correction term, the curvature energy, different forms of the Wigner term and powers of the relative neutron excess I=(N-Z)/A. Their coefficients have been determined by a least square fitting procedure to 2027 experimental atomic masses (G. Audi et al. (2003) [1]). The Coulomb diffuseness correction Z/A term or the charge exchange correction Z/A term plays the main role to improve the accuracy of the mass formula. The Wigner term and the curvature energy can also be used separately but their coefficients are very unstable. The different fits lead to a surface energy coefficient of around 17-18 MeV. A large equivalent rms radius ( r=1.22-1.24 fm) or a shorter central radius may be used. An rms deviation of 0.54 MeV can be reached between the experimental and theoretical masses. The remaining differences come probably mainly from the determination of the shell and pairing energies. Mass predictions of selected expressions have been compared to 161 new experimental masses and the correct agreement allows to provide extrapolations to masses of 656 selected exotic nuclei.

MassTRIX: mass translator into pathways.

PubMed

Suhre, Karsten; Schmitt-Kopplin, Philippe

2008-07-01

Recent technical advances in mass spectrometry (MS) have brought the field of metabolomics to a point where large numbers of metabolites from numerous prokaryotic and eukaryotic organisms can now be easily and precisely detected. The challenge today lies in the correct annotation of these metabolites on the basis of their accurate measured masses. Assignment of bulk chemical formula is generally possible, but without consideration of the biological and genomic context, concrete metabolite annotations remain difficult and uncertain. MassTRIX responds to this challenge by providing a hypothesis-driven approach to high precision MS data annotation. It presents the identified chemical compounds in their genomic context as differentially colored objects on KEGG pathway maps. Information on gene transcription or differences in the gene complement (e.g. samples from different bacterial strains) can be easily added. The user can thus interpret the metabolic state of the organism in the context of its potential and, in the case of submitted transcriptomics data, real enzymatic capacities. The MassTRIX web server is freely accessible at http://masstrix.org.

Enhanced Production of Anthraquinones and Phenolic Compounds and Biological Activities in the Cell Suspension Cultures of Polygonum multiflorum

PubMed Central

Thiruvengadam, Muthu; Rekha, Kaliyaperumal; Rajakumar, Govindasamy; Lee, Taek-Jun; Kim, Seung-Hyun; Chung, Ill-Min

2016-01-01

Anthraquinones (AQs) and phenolic compounds are important phytochemicals that are biosynthesized in cell suspension cultures of Polygonum multiflorum. We wanted to optimize the effects of plant growth regulators (PGRs), media, sucrose, l-glutamine, jasmonic acid (JA), and salicylic acid (SA) for the production of phytochemicals and biomass accumulation in a cell suspension culture of P. multiflorum. The medium containing Murashige and Skoog (MS) salts and 4% sucrose supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid, 0.5 mg/L thidiazuron, and 100 µM l-glutamine at 28 days of cell suspension culture was suitable for biomass accumulation and AQ production. Maximum biomass accumulation (12.5 and 12.35 g fresh mass (FM); 3 and 2.93 g dry mass (DM)) and AQ production (emodin 295.20 and 282 mg/g DM; physcion 421.55 and 410.25 mg/g DM) were observed using 100 µM JA and SA, respectively. JA- and SA-elicited cell cultures showed several-fold higher biomass accumulation and AQ production than the control cell cultures. Furthermore, the cell suspension cultures effectively produced 23 phenolic compounds, such as flavonols and hydroxycinnamic and hydroxybenzoic acid derivatives. PGR-, JA-, and SA-elicited cell cultures produced a higher amount of AQs and phenolic compounds. Because of these metabolic changes, the antioxidant, antimicrobial, and anticancer activities were high in the PGR-, JA-, and SA-elicited cell cultures. The results showed that the elicitors (JA and SA) induced the enhancement of biomass accumulation and phytochemical (AQs and phenolic compounds) production as well as biological activities in the cell suspension cultures of P. multiflorum. This optimized protocol can be developed for large-scale biomass accumulation and production of phytochemicals (AQs and phenolic compounds) from cell suspension cultures, and the phytochemicals can be used for various biological activities. PMID:27854330

Imaging mass spectrometer with mass tags

DOEpatents

Felton, James S.; Wu, Kuang Jen; Knize, Mark G.; Kulp, Kristen S.; Gray, Joe W.

2010-06-01

A method of analyzing biological material by exposing the biological material to a recognition element, that is coupled to a mass tag element, directing an ion beam of a mass spectrometer to the biological material, interrogating at least one region of interest area from the biological material and producing data, and distributing the data in plots.

Citrus leprosis virus C Infection Results in Hypersensitive-Like Response, Suppression of the JA/ET Plant Defense Pathway and Promotion of the Colonization of Its Mite Vector

PubMed Central

Arena, Gabriella D.; Ramos-González, Pedro L.; Nunes, Maria A.; Ribeiro-Alves, Marcelo; Camargo, Luis E. A.; Kitajima, Elliot W.; Machado, Marcos A.; Freitas-Astúa, Juliana

2016-01-01

Leprosis is a serious disease of citrus caused by Citrus leprosis virus C (CiLV-C, genus Cilevirus) whose transmission is mediated by false spider mites of the genus Brevipalpus. CiLV-C infection does not systemically spread in any of its known host plants, thus remaining restricted to local lesions around the feeding sites of viruliferous mites. To get insight into this unusual pathosystem, we evaluated the expression profiles of genes involved in defense mechanisms of Arabidopsis thaliana and Citrus sinensis upon infestation with non-viruliferous and viruliferous mites by using reverse-transcription qPCR. These results were analyzed together with the production of reactive oxygen species (ROS) and the appearance of dead cells as assessed by histochemical assays. After interaction with non-viruliferous mites, plants locally accumulated ROS and triggered the salicylic acid (SA) and jasmonate/ethylene (JA/ET) pathways. ERF branch of the JA/ET pathways was highly activated. In contrast, JA pathway genes were markedly suppressed upon the CiLV-C infection mediated by viruliferous mites. Viral infection also intensified the ROS burst and cell death, and enhanced the expression of genes involved in the RNA silencing mechanism and SA pathway. After 13 days of infestation of two sets of Arabidopsis plants with non-viruliferous and viruliferous mites, the number of mites in the CiLV-C infected Arabidopsis plants was significantly higher than in those infested with the non-viruliferous ones. Oviposition of the viruliferous mites occurred preferentially in the CiLV-C infected leaves. Based on these results, we postulated the first model of plant/Brevipalpus mite/cilevirus interaction in which cells surrounding the feeding sites of viruliferous mites typify the outcome of a hypersensitive-like response, whereas viral infection induces changes in the behavior of its vector. PMID:27933078

MASS SPECTROMETER

DOEpatents

White, F.A.

1960-08-23

A mass spectrometer is designed with a first adjustable magnetic field for resolving an ion beam into beams of selected masses, a second adjustable magnetic field for further resolving the ion beam from the first field into beams of selected masses, a thin foil disposed in the path of the beam between the first and second magnets to dissociate molecular ions incident thereon, an electrostatic field for further resolving the ion beam from the second field into beams of selected masses, and a detector disposed adjacent to the electrostatic field to receive the ion beam.

A non-resonant mass sensor to eliminate the "missing mass" effect during mass measurement of biological materials

NASA Astrophysics Data System (ADS)

Shrikanth, V.; Bobji, M. S.

2014-10-01

Resonant sensors and crystal oscillators for mass detection need to be excited at very high natural frequencies (MHz). Use of such systems to measure mass of biological materials affects the accuracy of mass measurement due to their viscous and/or viscoelastic properties. The measurement limitation of such sensor system is the difficulty in accounting for the "missing mass" of the biological specimen in question. A sensor system has been developed in this work, to be operated in the stiffness controlled region at very low frequencies as compared to its fundamental natural frequency. The resulting reduction in the sensitivity due to non-resonant mode of operation of this sensor is compensated by the high resolution of the sensor. The mass of different aged drosophila melanogaster (fruit fly) is measured. The difference in its mass measurement during resonant mode of operation is also presented. That, viscosity effects do not affect the working of this non-resonant mass sensor is clearly established by direct comparison.

Mass predictions from the Garvey-Kelson mass relations

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

Jaenecke, J.; Masson, P.J.

Part A: The transverse Garvey-Kelson mass relation represents a homogeneous third-order partial difference equation. Procedures are described for estimating masses of nuclei with Ngreater than or equal toZ from the most general solution of this difference equation subject to a chi/sup 2/ minimization, using the recent atomic mass adjustment of Wapstra, Audi, and Hoekstra as a boundary condition. A judicious division of the input data in subsets of neutron-rich and proton-rich nuclei had to be introduced to reduce systematic errors in long-range extrapolations. Approximately 5600 mass-excess values for nuclei with 2less than or equal toZless than or equal to103, 4lessmore » than or equal toNless than or equal to157, and Ngreater than or equal toZ (except N = Z odd for A<40) have been calculated. The standard deviation for reproducing the known mass-excess values is sigma/sub m/approx. =103 keV.« less

Mass Media Types: Three Q-Analyses of Mass Media Exposure.

ERIC Educational Resources Information Center

Walker, James R.

The purpose of a mass media study was to (l) identify mass media types (patterns of exposure to mass media content) among seventh graders, high school juniors, and adults in a given geographic area; (2) show similarities and differences in the mass media types isolated for these three age groups; (3) pinpoint demographic variables most strongly…

Heavy quark masses

NASA Technical Reports Server (NTRS)

Testa, Massimo

1990-01-01

In the large quark mass limit, an argument which identifies the mass of the heavy-light pseudoscalar or scalar bound state with the renormalized mass of the heavy quark is given. The following equation is discussed: m(sub Q) = m(sub B), where m(sub Q) and m(sub B) are respectively the mass of the heavy quark and the mass of the pseudoscalar bound state.

Differential Effects of Methyl Jasmonate on the Expression of the Early Light-Inducible Proteins and Other Light-Regulated Genes in Barley1

PubMed Central

Wierstra, Inken; Kloppstech, Klaus

2000-01-01

The effects of methyl jasmonate (JA-Me) on early light-inducible protein (ELIP) expression in barley (Hordeum vulgare L. cv Apex) have been studied. Treatment of leaf segments with JA-Me induces the same symptoms as those exhibited by norflurazon bleaching, including a loss of pigments and enhanced light stress that results in increased ELIP expression under both high- and low-light conditions. The expression of both low- and high-molecular-mass ELIP families is considerably down-regulated by JA-Me at the transcript and protein levels. This repression occurs despite increased photoinhibition measurable as a massive degradation of D1 protein and a delayed recovery of photosystem II activity. In JA-Me-treated leaf segments, the decrease of the photochemical efficiency of photosystem II under high light is substantially more pronounced as compared to controls in water. The repression of ELIP expression by JA-Me is superimposed on the effect of the increased light stress that leads to enhanced ELIP expression. The fact that the reduction of ELIP transcript levels is less pronounced than those of light-harvesting complex II and small subunit of Rubisco transcripts indicates that light stress is still affecting gene expression in the presence of JA-Me. The jasmonate-induced protein transcript levels that are induced by JA-Me decline under light stress conditions. PMID:11027731

Neutrino mass as the probe of intermediate mass scales

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

Senjanovic, G.

1980-01-01

A discussion of the calculability of neutrino mass is presented. The possibility of neutrinos being either Dirac or Majorana particles is analyzed in detail. Arguments are offered in favor of the Majorana case: the smallness of neutrino mass is linked to the maximality of parity violation in weak interactions. It is shown how the measured value of neutrino mass would probe the existence of an intermediate mass scale, presumably in the TeV region, at which parity is supposed to become a good symmetry. Experimental consequences of the proposed scheme are discussed, in particular the neutrino-less double ..beta.. decay, where observationmore » would provide a crucial test of the model, and rare muon decays such as ..mu.. ..-->.. e..gamma.. and ..mu.. ..-->.. ee anti e. Finally, the embedding of this model in an O(10) grand unified theory is analyzed, with the emphasis on the implications for intermediate mass scales that it offers. It is concluded that the proposed scheme provides a distinct and testable alternative for understanding the smallness of neutrino mass. 4 figures.« less

Linear mass actuator

NASA Technical Reports Server (NTRS)

Holloway, Sidney E., III (Inventor); Crossley, Edward A., Jr. (Inventor); Jones, Irby W. (Inventor); Miller, James B. (Inventor); Davis, C. Calvin (Inventor); Behun, Vaughn D. (Inventor); Goodrich, Lewis R., Sr. (Inventor)

1992-01-01

A linear mass actuator includes an upper housing and a lower housing connectable to each other and having a central passageway passing axially through a mass that is linearly movable in the central passageway. Rollers mounted in the upper and lower housings in frictional engagement with the mass translate the mass linearly in the central passageway and drive motors operatively coupled to the roller means, for rotating the rollers and driving the mass axially in the central passageway.

On Defining Mass

NASA Astrophysics Data System (ADS)

Hecht, Eugene

2011-01-01

Though central to any pedagogical development of physics, the concept of mass is still not well understood. Properly defining mass has proven to be far more daunting than contemporary textbooks would have us believe. And yet today the origin of mass is one of the most aggressively pursued areas of research in all of physics. Much of the excitement surrounding the Large Hadron Collider at CERN is associated with discovering the mechanism responsible for the masses of the elementary particles. This paper will first briefly examine the leading definitions, pointing out their shortcomings. Then, utilizing relativity theory, it will propose—for consideration by the community of physicists—a conceptual definition of mass predicated on the more fundamental concept of energy, more fundamental in that everything that has mass has energy, yet not everything that has energy has mass.

Origins of mass

NASA Astrophysics Data System (ADS)

Wilczek, Frank

2012-10-01

Newtonian mechanics posited mass as a primary quality of matter, incapable of further elucidation. We now see Newtonian mass as an emergent property. That mass-concept is tremendously useful in the approximate description of baryon-dominated matter at low energy — that is, the standard "matter" of everyday life, and of most of science and engineering — but it originates in a highly contingent and non-trivial way from more basic concepts. Most of the mass of standard matter, by far, arises dynamically, from back-reaction of the color gluon fields of quantum chromodynamics (QCD). Additional quantitatively small, though physically crucial, contributions come from the intrinsic masses of elementary quanta (electrons and quarks). The equations for massless particles support extra symmetries — specifically scale, chiral, and gauge symmetries. The consistency of the standard model relies on a high degree of underlying gauge and chiral symmetry, so the observed non-zero masses of many elementary particles ( W and Z bosons, quarks, and leptons) requires spontaneous symmetry breaking. Superconductivity is a prototype for spontaneous symmetry breaking and for mass-generation, since photons acquire mass inside superconductors. A conceptually similar but more intricate form of all-pervasive ( i.e. cosmic) superconductivity, in the context of the electroweak standard model, gives us a successful, economical account of W and Z boson masses. It also allows a phenomenologically successful, though profligate, accommodation of quark and lepton masses. The new cosmic superconductivity, when implemented in a straightforward, minimal way, suggests the existence of a remarkable new particle, the so-called Higgs particle. The mass of the Higgs particle itself is not explained in the theory, but appears as a free parameter. Earlier results suggested, and recent observations at the Large Hadron Collider (LHC) may indicate, the actual existence of the Higgs particle, with mass m H �

Buckwheat (Fagopyrum esculentum M.) Sprout Treated with Methyl Jasmonate (MeJA) Improved Anti-Adipogenic Activity Associated with the Oxidative Stress System in 3T3-L1 Adipocytes

PubMed Central

Lee, Young-Jun; Kim, Kui-Jin; Park, Kee-Jai; Yoon, Bo-Ra; Lim, Jeong-Ho; Lee, Ok-Hwan

2013-01-01

Buckwheat sprouts contain various bioactive compounds including rutin which have a number of biological activities. We have previously shown that buckwheat sprouts (TBWE) treated with methyl jasmonate (MeJA) significantly increased the amount of phenolics and the antioxidant activity. The aim of this study was to demonstrate the effect of TBWE on anti-adipogenesis and pro-oxidant enzyme in 3T3-L1 adipocytes. We also evaluated the anti-oxidative activity of TBWE in adipocytes by using the nitroblue tetrazolium assay. Our data showed that TBWE markedly inhibited adipocyte differentiation and ROS production in 3T3-L1 cells compared with control groups. Moreover, TBWE has strongly shown the inhibition of adipogenic transcription factor as well as pro-oxidant enzymes. Together, we demonstrate that the MeJA treatment significantly increased the amount of phenolic compound, resulting in the suppression of adipogenesis and ROS production in the 3T3-L1 cells. These findings indicate that TBWE has the potential for anti-adipogenesis activity with anti-oxidative properties. PMID:23344050

Influence of Altered Mass Loading on Testosterone Levels and Testicular Mass

NASA Technical Reports Server (NTRS)

Wang, Tommy J.; Ortiz, R. M.; Wade, C. E.; Hargens, Alan R. (Technical Monitor)

1996-01-01

Effects of altered load on testosterone levels and testicular mass in mammals are not well defined. Two separate studies (loading;centrifuged; +2G(sub z) and unloading;hindlimb suspension;HLS) were conducted to provide a better understanding of the effects of mass loading on testosterone levels and testicular mass. Daily urine samples were collected, and testicular mass measured at the end of the study. +2G(sub z): Sprague-Dawley rats (230-250 g) were centrifuged for 12 days at +2G(sub z): 8 centrifuged (EC) and 8 off centrifuge controls (OCC). EC had lower body mass, however relative testicular mass was greater. EC exhibited an increase in excreted testosterone levels between days 2 (T2) and 6 (T6), and returned to baseline at T9. HLS: To assess the effects of unloading Sprague-Dawley rats (125-150 g) were studied for 12 days: 10 suspended (Exp) and 10 ambulatory (Ctl). Exp had lower body mass during the study, with reduced absolute and relative testicular mass. Exp demonstrated lower excreted testosterone levels from T5-T12. Conclusions: Loading appears to stimulate anabolism, as opposed to unloading, as indicated by greater relative testicular mass and excreted testosterone levels. Reported changes in muscle mass during loading and unloading coincide with similar changes in excreted testosterone levels.

Micro-mass standards to calibrate the sensitivity of mass comparators

NASA Astrophysics Data System (ADS)

Madec, Tanguy; Mann, Gaëlle; Meury, Paul-André; Rabault, Thierry

2007-10-01

In mass metrology, the standards currently used are calibrated by a chain of comparisons, performed using mass comparators, that extends ultimately from the international prototype (which is the definition of the unit of mass) to the standards in routine use. The differences measured in the course of these comparisons become smaller and smaller as the standards approach the definitions of their units, precisely because of how accurately they have been adjusted. One source of uncertainty in the determination of the difference of mass between the mass compared and the reference mass is the sensitivity error of the comparator used. Unfortunately, in the market there are no mass standards small enough (of the order of a few hundreds of micrograms) for a valid evaluation of this source of uncertainty. The users of these comparators therefore have no choice but to rely on the characteristics claimed by the makers of the comparators, or else to determine this sensitivity error at higher values (at least 1 mg) and interpolate from this result to smaller differences of mass. For this reason, the LNE decided to produce and calibrate micro-mass standards having nominal values between 100 µg and 900 µg. These standards were developed, then tested in multiple comparisons on an A5 type automatic comparator. They have since been qualified and calibrated in a weighing design, repeatedly and over an extended period of time, to establish their stability with respect to oxidation and the harmlessness of the handling and storage procedure associated with their use. Finally, the micro-standards so qualified were used to characterize the sensitivity errors of two of the LNE's mass comparators, including the one used to tie France's Platinum reference standard (Pt 35) to stainless steel and superalloy standards.

Pulsation, Mass Loss and the Upper Mass Limit

NASA Astrophysics Data System (ADS)

Klapp, J.; Corona-Galindo, M. G.

1990-11-01

RESUMEN. La existencia de estrellas con masas en exceso de 100 M0 ha sido cuestionada por mucho tiempo. Lfmites superiores para la masa de 100 M0 han sido obtenidos de teorfas de pulsaci6n y formaci6n estelar. En este trabajo nosotros primero investigamos la estabilidad radial de estrellas masivas utilizando la aproximaci6n clasica cuasiadiabatica de Ledoux, la aproximaci6n cuasiadiabatica de Castor y un calculo completamente no-adiabatico. Hemos encontrado que los tres metodos de calculo dan resultados similares siempre y cuando una pequefia regi6n de las capas externas de la estrella sea despreciada para la aproximaci6n clasica. La masa crftica para estabilidad de estrellas masivas ha sido encontrada en acuerdo a trabajos anteriores. Explicamos Ia discrepancia entre este y trabajos anteriores por uno de los autores. Discunmos calculos no-lineales y perdida de masa con respecto a) lfmite superior de masa. The existence of stars with masses in excess of 100 M0 has been questioned for a very long time. Upper mass limits of 100 Me have been obtained from pulsation and star formation theories. In this work we first investigate the radial stability of massive stars using the classical Ledoux's quasiadiabatic approximation. the Castor quasiadiabatic approximation and a fully nonadiabatic calculation. We have found that the three methods of calculation give similar results provided that a small region in outer layers of the star be neglected for the classical approximation. The critical mass for stability of massive stars is found to be in agreement with previous work. We explain the reason for the discrepancy between this and previous work by one of the authors. We discuss non-linear calculations and mass loss with regard to the upper mass limit. Key words: STARS-MASS FUNCTION - STARS-MASS LOSS - STARS-PULSATION

Mass spectrometric immunoassay

DOEpatents

Nelson, Randall W; Williams, Peter; Krone, Jennifer Reeve

2007-12-04

Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

Mass spectrometric immunoassay

DOEpatents

Nelson, Randall W; Williams, Peter; Krone, Jennifer Reeve

2013-07-16

Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

Mass spectrometric immunoassay

DOEpatents

Nelson, Randall W.; Williams, Peter; Krone, Jennifer Reeve

2005-12-13

Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

Safety and quality parameters of ready-to-cook minced pork meat products supplemented with Helianthus tuberosus L. tubers fermented by BLIS producing lactic acid bacteria.

PubMed

Stimbirys, Arturas; Bartkiene, Elena; Siugzdaite, Jurate; Augeniene, Dovile; Vidmantiene, Daiva; Juodeikiene, Grazina; Maruska, Audrius; Stankevicius, Mantas; Cizeikiene, Dalia

2015-07-01

The aim of this study was to evaluate the influence of additives of Jerusalem artichoke (JA), fermented with P. acidilactici KTU05-7, P. pentosaceus KTU05-9, L. sakei KTU05-6, on the quality and safety parameters of ready - to cook - minced pork (RCMP). Fermented JA additives reduced pH of the meat products and decreased water holding capacity (WHC) from 2.01 till 2.93 %. Concentrations of biogenic amines in RCMP with additives of the lactic acid bacteria (LAB) - fermented JA were significantly lower comparing with control sample. The number of pathogenic bacteria in artificially contaminated meat samples was significantly reduced in case of LAB-fermented JA additives. The highest antimicrobial activity was obtained using P. acidilactici fermented JA additives. The amounts of microbial pathogens E. coli and Ent. faecalis, S. aureus and Streptococcus spp. were determined 3.41, 3.38, 3,96 and 4.74 log CFU/g correspondingly, whereas without LAB-fermented JA additives were 8.94, 7.75, 8.82 and 8.58 log CFU/g, correspondingly. A possibility to improve sensory properties (flavor) of RCMP using LAB fermented JA additives was investigated. The composition of volatile compounds of RCMP without additive and with LAB-fermented JA additives was analyzed using gas chromatography-mass spectrometry (GC-MS). The results of sensory evaluation of meat products supplemented with fermented JA additives revealed specific odor, which is pleasant and acceptable for consumers might be explainable that LAB-fermented JA additives have shown considerable differences mainly due to the accumulation of volatiles such as toluene, ethylbenzene, decane, undecane, 2 methyl undecane. N-morpholinomethyl-isopropyl-sulfide, 6-undecilamine and N,N-dimethyl-1-pentadecanamine were not determined in RCMP with LAB-fermented JA additives. The results obtained show, that P. acidilactici fermented JA 5 % additive is most suitable for the RCMP processing in order to prevent microbiological spoilage, increase

Counting Molecules by Desorption Ionization and Mass Spectrometry/Mass Spectrometry.

ERIC Educational Resources Information Center

Cooks, R. G.; Busch, K. L.

1982-01-01

Discusses two newer methods in mass spectrometry and shows how they can increase signal and signal-to-noise ratios, respectively. The first method, desorption ionization (DI), increases sensitivity while the second method, mass spectrometry/mass spectrometry (MS/MS), increases specificity. Together, the two methods offer improved analytical…

Relationship between mass-flux reduction and source-zone mass removal: analysis of field data.

PubMed

Difilippo, Erica L; Brusseau, Mark L

2008-05-26

The magnitude of contaminant mass-flux reduction associated with a specific amount of contaminant mass removed is a key consideration for evaluating the effectiveness of a source-zone remediation effort. Thus, there is great interest in characterizing, estimating, and predicting relationships between mass-flux reduction and mass removal. Published data collected for several field studies were examined to evaluate relationships between mass-flux reduction and source-zone mass removal. The studies analyzed herein represent a variety of source-zone architectures, immiscible-liquid compositions, and implemented remediation technologies. There are two general approaches to characterizing the mass-flux-reduction/mass-removal relationship, end-point analysis and time-continuous analysis. End-point analysis, based on comparing masses and mass fluxes measured before and after a source-zone remediation effort, was conducted for 21 remediation projects. Mass removals were greater than 60% for all but three of the studies. Mass-flux reductions ranging from slightly less than to slightly greater than one-to-one were observed for the majority of the sites. However, these single-snapshot characterizations are limited in that the antecedent behavior is indeterminate. Time-continuous analysis, based on continuous monitoring of mass removal and mass flux, was performed for two sites, both for which data were obtained under water-flushing conditions. The reductions in mass flux were significantly different for the two sites (90% vs. approximately 8%) for similar mass removals ( approximately 40%). These results illustrate the dependence of the mass-flux-reduction/mass-removal relationship on source-zone architecture and associated mass-transfer processes. Minimal mass-flux reduction was observed for a system wherein mass removal was relatively efficient (ideal mass-transfer and displacement). Conversely, a significant degree of mass-flux reduction was observed for a site wherein mass

Mass-Fatality Incident Preparedness Among Faith-Based Organizations.

PubMed

Zhi, Qi; Merrill, Jacqueline A; Gershon, Robyn R

2017-12-01

organizations (73%) and less likely with local death care sector organizations (27%) or Departments of Health (DOHs; 32%). The study suggests improvements are needed in terms of staff training in general, and specifically, drills with planning partners are needed. Greater cooperation and inclusion of FBOs in national planning and training will likely benefit overall MFI preparedness in the US. Zhi Q , Merrill JA , Gershon RR . Mass-fatality incident preparedness among faith-based organizations. Prehosp Disaster Med. 2017;32(6):596-603.

Hierarchical Galaxy Growth and Scatter in the Stellar Mass-Halo Mass Relation

NASA Astrophysics Data System (ADS)

Gu, Meng; Conroy, Charlie; Behroozi, Peter

2016-12-01

The relation between galaxies and dark matter halos reflects the combined effects of many distinct physical processes. Observations indicate that the z = 0 stellar mass-halo mass (SMHM) relation has remarkably small scatter in stellar mass at fixed halo mass (≲0.2 dex), with little dependence on halo mass. We investigate the origins of this scatter by combining N-body simulations with observational constraints on the SMHM relation. We find that at the group and cluster scale ({M}{vir}\\gt {10}14 {M}⊙ ) the scatter due purely to hierarchical assembly is ≈ 0.16 dex, which is comparable to recent direct observational estimates. At lower masses, mass buildup since z≈ 2 is driven largely by in situ growth. We include a model for the in situ buildup of stellar mass and find that an intrinsic scatter in this growth channel of 0.2 dex produces a relation between scatter and halo mass that is consistent with observations from {10}12 {M}⊙ \\lt {M}{vir}\\lt {10}14.75 {M}⊙ . The approximately constant scatter across a wide range of halo masses at z = 0 thus appears to be a coincidence, as it is determined largely by in situ growth at low masses and by hierarchical assembly at high masses. These results indicate that the scatter in the SMHM relation can provide unique insight into the regularity of the galaxy formation process.

The Mass Distribution of Companions to Low-mass White Dwarfs

NASA Astrophysics Data System (ADS)

Andrews, Jeff J.; Price-Whelan, Adrian M.; Agüeros, Marcel A.

2014-12-01

Measuring the masses of companions to single-line spectroscopic binary stars is (in general) not possible because of the unknown orbital plane inclination. Even when the mass of the visible star can be measured, only a lower limit can be placed on the mass of the unseen companion. However, since these inclination angles should be isotropically distributed, for a large enough, unbiased sample, the companion mass distribution can be deconvolved from the distribution of observables. In this work, we construct a hierarchical probabilistic model to infer properties of unseen companion stars given observations of the orbital period and projected radial velocity of the primary star. We apply this model to three mock samples of low-mass white dwarfs (LMWDs; M <~ 0.45 M ⊙) and a sample of post-common-envelope binaries. We use a mixture of two Gaussians to model the WD and neutron star (NS) companion mass distributions. Our model successfully recovers the initial parameters of these test data sets. We then apply our model to 55 WDs in the extremely low-mass (ELM) WD Survey. Our maximum a posteriori model for the WD companion population has a mean mass μWD = 0.74 M ⊙, with a standard deviation σWD = 0.24 M ⊙. Our model constrains the NS companion fraction f NS to be <16% at 68% confidence. We make samples from the posterior distribution publicly available so that future observational efforts may compute the NS probability for newly discovered LMWDs.

The Stellar Mass-Halo Mass Relation for Low-mass X-Ray Groups At 0.5< z< 1 in the CDFS With CSI

NASA Astrophysics Data System (ADS)

Patel, Shannon G.; Kelson, Daniel D.; Williams, Rik J.; Mulchaey, John S.; Dressler, Alan; McCarthy, Patrick J.; Shectman, Stephen A.

2015-02-01

Since z˜ 1, the stellar mass density locked in low-mass groups and clusters has grown by a factor of ˜8. Here, we make the first statistical measurements of the stellar mass content of low-mass X-ray groups at 0.5\\lt z\\lt 1, enabling the calibration of stellar-to-halo mass scales for wide-field optical and infrared surveys. Groups are selected from combined Chandra and XMM-Newton X-ray observations in the Chandra Deep Field South. These ultra-deep observations allow us to identify bona fide low-mass groups at high redshift and enable measurements of their total halo masses. We compute aggregate stellar masses for these halos using galaxies from the Carnegie-Spitzer-IMACS (CSI) spectroscopic redshift survey. Stars comprise ˜3%-4% of the total mass of group halos with masses {{10}12.8}\\lt {{M}200}/{{M}⊙ }\\lt {{10}13.5} (about the mass of Fornax and one-fiftieth the mass of Virgo). Complementing our sample with higher mass halos at these redshifts, we find that the stellar-to-halo mass ratio decreases toward higher halo masses, consistent with other work in the local and high redshift universe. The observed scatter about the stellar-halo mass relation is σ ˜ 0.25 dex, which is relatively small and suggests that total group stellar mass can serve as a rough proxy for halo mass. We find no evidence for any significant evolution in the stellar-halo mass relation since z≲ 1. Quantifying the stellar content in groups since this epoch is critical given that hierarchical assembly leads to such halos growing in number density and hosting increasing shares of quiescent galaxies. This Letter includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile. This research is based on observations made with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555.

The origin of mass

NASA Astrophysics Data System (ADS)

Froggatt*, C. D.

2003-01-01

The quark-lepton mass problem and the ideas of mass protection are reviewed. The hierarchy problem and suggestions for its resolution, including Little Higgs models, are discussed. The Multiple Point Principle (MPP) is introduced and used within the Standard Model (SM) to predict the top quark and Higgs particle masses. Mass matrix ansätze are considered; in particular we discuss the lightest family mass generation model, in which all the quark mixing angles are successfully expressed in terms of simple expressions involving quark mass ratios. It is argued that an underlying chiral flavour symmetry is responsible for the hierarchical texture of the fermion mass matrices. The phenomenology of neutrino mass matrices is briefly discussed.

Abdominal mass

MedlinePlus

... lumpy mass in the right upper quadrant. Liver enlargement (hepatomegaly) can cause a firm, irregular mass below ... the kidney (usually only affects one kidney). Spleen enlargement (splenomegaly) can sometimes be felt in the left- ...

Scrotal masses

MedlinePlus

... on this page, please enable JavaScript. A scrotal mass is a lump or bulge that can be ... sac that contains the testicles. Causes A scrotal mass can be noncancerous (benign) or cancerous (malignant). Benign ...

Measuring the Dust Flux and Dust Particle Mass Distribution in the Saturn Rings with HRD Dust Instrument on the Cassini Mission

NASA Astrophysics Data System (ADS)

Tuzzolino, A. J.; Economou, T. E.

In July 2004, the Cassini spacecraft will go into the Saturn orbit and start a 4 year intensive investigation of the planet itself, its multiple satellites and its rings with a multinational instrument payload. The High Rate Detectors (HRD) instrument provided by the Laboratory of Astrophysics and Space Research of the University of is part of the German Cosmic Dust Analyzer (CDA) and its main scientific objective is to provide quantitative measurements and mass distributions of dust particles in the rings of Saturn in the 10-11 to 10-4 grams mass range. The HRD instrument consists of two dust detectors -- a 20 and a 200 cm2 polyvinylidene fluoride (PVDF) sensors -- and an electronic box that contains all the analog and digital electronics and in addition provides interface between the HRD and CDA instrument. The CDA stores all the HRD data in its memory and transmits the data to Earth. The HRD weighs 1.7 kg and consumes 1.8 W of power [1]. The HRD instrument was fully calibrated through the entire mass range using two dust particle accelerators at Heidelberg and Munich in Germany. The HRD electronics is very fast and it will provide spatial and time distributions of up to 0.1 second. It can handle rates up to 104 counts/sec expected to be encountered during the Saturn ring crossings without any dead time. The HRD instrument operated successfully during all of the time that it was under power and detected many interplanetary dust particles. Almost all of these particles were close to the lowest mass threshold. References 1 A.J. TUZZOLINO, T.E. ECONOMOU, R.B. MCKIBBEN, J.A. SIMPSON, J.A.M. MCDONNELL, M.J. BURCHELL, B.A.M. VAUGHAN, P. TSOU, M.S. HANNER, B.C. CLARK AND D.E. BROWNLEE. THE DUST FLUX MONITOR INSTRUMENT FOR THE STARDUST MISSION TO COMET WILD-2, J. GEOPHYS. RES., 108, DOI:10.1029/2003JE002091, 2003.

Upper bounds on superpartner masses from upper bounds on the Higgs boson mass.

PubMed

Cabrera, M E; Casas, J A; Delgado, A

2012-01-13

The LHC is putting bounds on the Higgs boson mass. In this Letter we use those bounds to constrain the minimal supersymmetric standard model (MSSM) parameter space using the fact that, in supersymmetry, the Higgs mass is a function of the masses of sparticles, and therefore an upper bound on the Higgs mass translates into an upper bound for the masses for superpartners. We show that, although current bounds do not constrain the MSSM parameter space from above, once the Higgs mass bound improves big regions of this parameter space will be excluded, putting upper bounds on supersymmetry (SUSY) masses. On the other hand, for the case of split-SUSY we show that, for moderate or large tanβ, the present bounds on the Higgs mass imply that the common mass for scalars cannot be greater than 10(11)  GeV. We show how these bounds will evolve as LHC continues to improve the limits on the Higgs mass.

A Phenolic Extract Obtained from Methyl Jasmonate-Treated Strawberries Enhances Apoptosis in a Human Cervical Cancer Cell Line.

PubMed

Spagnuolo, Carmela; Flores, Gema; Russo, Gian Luigi; Ruiz Del Castillo, Maria Luisa

2016-10-01

In the present study, we evaluated the effect of methyl jasmonate (MeJA) treatment on strawberry phenolic composition. Strawberry extracts contain a mixture of phenolic compounds possessing several biological properties. We demonstrated that these extracts were more effective in inducing apoptosis in HeLa cells compared to phenolic preparations derived from untreated strawberries. Treatment of strawberries with 0.5% MeJA resulted in increased polyphenols content (from 7.4 to 8.6 mM quercetin equivalents) and antioxidant properties (from 3.9 to 4.6 mM quercetin equivalents). The identification and quantification of phenolic compounds by liquid chromatography-mass spectrometry in the strawberry extracts showed that cyanidin glucoside, pelargonidin glucoside, and ellagic glucoside acid were significantly higher in strawberries treated with MeJA. Phenolic extracts from MeJA-treated strawberries significantly decreased the cell viability in HeLa cells, compared to extracts derived from untreated fruits. We hypothesized that the enhanced apoptotic activity of MeJA-treated strawberries was due to a synergistic or additive effect of different phenolic compounds present in the extract, rather than the activity of a single molecule.

Hartree-Fock mass formulas and extrapolation to new mass data

NASA Astrophysics Data System (ADS)

Goriely, S.; Samyn, M.; Heenen, P.-H.; Pearson, J. M.; Tondeur, F.

2002-08-01

The two previously published Hartree-Fock (HF) mass formulas, HFBCS-1 and HFB-1 (HF-Bogoliubov), are shown to be in poor agreement with new Audi-Wapstra mass data. The problem lies first with the prescription adopted for the cutoff of the single-particle spectrum used with the δ-function pairing force, and second with the Wigner term. We find an optimal mass fit if the spectrum is cut off both above EF+15 MeV and below EF-15 MeV, EF being the Fermi energy of the nucleus in question. In addition to the Wigner term of the form VW exp(-λ|N-Z|/A) already included in the two earlier HF mass formulas, we find that a second Wigner term linear in |N-Z| leads to a significant improvement in lighter nuclei. These two features are incorporated into our new Hartree-Fock-Bogoliubov model, which leads to much improved extrapolations. The 18 parameters of the model are fitted to the 2135 measured masses for N,Z>=8 with an rms error of 0.674 MeV. With this parameter set a complete mass table, labeled HFB-2, has been constructed, going from one drip line to the other, up to Z=120. The new pairing-cutoff prescription favored by the new mass data leads to weaker neutron-shell gaps in neutron-rich nuclei.

Cluster secondary ion mass spectrometry microscope mode mass spectrometry imaging.

PubMed

Kiss, András; Smith, Donald F; Jungmann, Julia H; Heeren, Ron M A

2013-12-30

Microscope mode imaging for secondary ion mass spectrometry is a technique with the promise of simultaneous high spatial resolution and high-speed imaging of biomolecules from complex surfaces. Technological developments such as new position-sensitive detectors, in combination with polyatomic primary ion sources, are required to exploit the full potential of microscope mode mass spectrometry imaging, i.e. to efficiently push the limits of ultra-high spatial resolution, sample throughput and sensitivity. In this work, a C60 primary source was combined with a commercial mass microscope for microscope mode secondary ion mass spectrometry imaging. The detector setup is a pixelated detector from the Medipix/Timepix family with high-voltage post-acceleration capabilities. The system's mass spectral and imaging performance is tested with various benchmark samples and thin tissue sections. The high secondary ion yield (with respect to 'traditional' monatomic primary ion sources) of the C60 primary ion source and the increased sensitivity of the high voltage detector setup improve microscope mode secondary ion mass spectrometry imaging. The analysis time and the signal-to-noise ratio are improved compared with other microscope mode imaging systems, all at high spatial resolution. We have demonstrated the unique capabilities of a C60 ion microscope with a Timepix detector for high spatial resolution microscope mode secondary ion mass spectrometry imaging. Copyright © 2013 John Wiley & Sons, Ltd.

Mass Communication: An Introduction; Theory and Practice of Mass Media in Society.

ERIC Educational Resources Information Center

Bittner, John R.

From the perspectives of historical, contemporary, and future interpretations of mass communication, this introduction to the theory and practice of mass media in society treats both the social context of mass communication and the hardware components that make it operable. The book discusses all mass media--newspapers, magazines, radio,…

[Conversion methods of freshwater snail tissue dry mass and ash free dry mass].

PubMed

Zhao, Wei-Hua; Wang, Hai-Jun; Wang, Hong-Zhu; Liu, Xue-Qin

2009-06-01

Mollusk biomass is usually expressed as wet mass with shell, but this expression fails to represent real biomass due to the high calcium carbonate content in shells. Tissue dry mass and ash free dry mass are relatively close to real biomass. However, the determination process of these two parameters is very complicated, and thus, it is necessary to establish simple and practical conversion methods for these two parameters. A total of six taxa of freshwater snails (Bellamya sp., Alocinma longicornis, Parafossarulus striatulus, Parafossarulus eximius, Semisulcospira cancellata, and Radix sp.) common in the Yangtze Basin were selected to explore the relations of their five shell dimension parameters, dry and wet mass with shells with their tissue dry mass and ash free dry mass. The regressions of the tissue dry mass and ash free dry mass with the five shell dimension parameters were all exponential (y = ax(b)). Among them, shell width and shell length were more precise (the average percentage error between observed and predicted value being 22.0% and 22.5%, respectively) than the other three parameters in the conversion of dry mass. Wet mass with shell could be directly converted to tissue dry mass and ash free dry mass, with an average percentage error of 21.7%. According to the essence of definition and the errors of conversion, ash free dry mass would be the optimum parameter to express snail biomass.

NGC 4051: Black hole mass and photon index-mass accretion rate correlation

NASA Astrophysics Data System (ADS)

Seifina, Elena; Chekhtman, Alexandre; Titarchuk, Lev

2018-05-01

We present a discovery of the correlation between the X-ray spectral (photon) index and mass accretion rate observed in an active galactic nucleus, NGC 4051. We analyzed spectral transition episodes observed in NGC 4051 using XMM-Newton, Suzaku and RXTE. We applied a scaling technique for a black hole (BH) mass evaluation which uses a correlation between the photon index and normalization of the seed (disk) component, which is proportional to a mass accretion rate. We developed an analytical model that shows the spectral (photon) index of the BH emergent spectrum undergoes an evolution from lower to higher values depending on a mass accretion rate in the accretion disk. We considered Cygnus X-1 and GRO J1550-564 as reference sources for which distances, inclination angles and the BH masses are evaluated by dynamical measurements. Application of the scaling technique for the photon index-mass accretion rate correlation provides an estimate of the black hole mass in NGC 4051 to be more than 6 × 105 solar masses.

Mechanical Properties of Aerojet, Thiokol, and JA2 High-Energy Gun Propellants at 1.5 m/s Deformation Rate

DTIC Science & Technology

2002-01-01

a2 6 n -32 4C La /C A> i c 4S Figure 5. Remains of specimens tested at 210, 630, and -32 0C. 5 I AUg 2001 "-1t AERQJET/"THIDKOL LOTS 0111W PM 4-40.00...10.00 +78.00 STRESS (Mra) -THIOKOL LOT LA -10T3--01 +5.C THIOKOL LOT JA-IEZ35--Z-02 JAZ LOT HCL03JO14-001 -28.00 AE J>:T? +0.00 4.00 0.0 .0 *20.0 O30 +40M0...WARREN MI 48397-5000 MATERIAL SCIENCE TEAM AMSSB RSS 14 BENET LABORATORIES J HERBERT AMSTA AR CCB M SENNETT R FISCELLA KANSAS ST M SOJA NATICK MA 01760

MPAI (mass probes aided ionization) method for total analysis of biomolecules by mass spectrometry.

PubMed

Honda, Aki; Hayashi, Shinichiro; Hifumi, Hiroki; Honma, Yuya; Tanji, Noriyuki; Iwasawa, Naoko; Suzuki, Yoshio; Suzuki, Koji

2007-01-01

We have designed and synthesized various mass probes, which enable us to effectively ionize various molecules to be detected with mass spectrometry. We call the ionization method using mass probes the "MPAI (mass probes aided ionization)" method. We aim at the sensitive detection of various biological molecules, and also the detection of bio-molecules by a single mass spectrometry serially without changing the mechanical settings. Here, we review mass probes for small molecules with various functional groups and mass probes for proteins. Further, we introduce newly developed mass probes for proteins for highly sensitive detection.

Digital imaging mass spectrometry.

PubMed

Bamberger, Casimir; Renz, Uwe; Bamberger, Andreas

2011-06-01

Methods to visualize the two-dimensional (2D) distribution of molecules by mass spectrometric imaging evolve rapidly and yield novel applications in biology, medicine, and material surface sciences. Most mass spectrometric imagers acquire high mass resolution spectra spot-by-spot and thereby scan the object's surface. Thus, imaging is slow and image reconstruction remains cumbersome. Here we describe an imaging mass spectrometer that exploits the true imaging capabilities by ion optical means for the time of flight mass separation. The mass spectrometer is equipped with the ASIC Timepix chip as an array detector to acquire the position, mass, and intensity of ions that are imaged by matrix-assisted laser desorption/ionization (MALDI) directly from the target sample onto the detector. This imaging mass spectrometer has a spatial resolving power at the specimen of (84 ± 35) μm with a mass resolution of 45 and locates atoms or organic compounds on a surface area up to ~2 cm(2). Extended laser spots of ~5 mm(2) on structured specimens allows parallel imaging of selected masses. The digital imaging mass spectrometer proves high hit-multiplicity, straightforward image reconstruction, and potential for high-speed readout at 4 kHz or more. This device demonstrates a simple way of true image acquisition like a digital photographic camera. The technology may enable a fast analysis of biomolecular samples in near future.

DETERMINING ION COMPOSITIONS USING AN ACCURATE MASS, TRIPLE QUADRUPOLE MASS SPECTROMETER

EPA Science Inventory

For the past decade, we have used double focusing mass spectrometers to determine
compositions of ions observed in mass spectra produced from compounds introduced by GC
based on measured exact masses of the ions and their +1 and +2 isotopic profiles arising from atoms of ...

Laser Ablation-Aerosol Mass Spectrometry-Chemical Ionization Mass Spectrometry for Ambient Surface Imaging

DOE PAGES

Berry, Jennifer L.; Day, Douglas A.; Elseberg, Tim; ...

2018-02-20

Mass spectrometry imaging is becoming an increasingly common analytical technique due to its ability to provide spatially resolved chemical information. In this paper, we report a novel imaging approach combining laser ablation with two mass spectrometric techniques, aerosol mass spectrometry and chemical ionization mass spectrometry, separately and in parallel. Both mass spectrometric methods provide the fast response, rapid data acquisition, low detection limits, and high-resolution peak separation desirable for imaging complex samples. Additionally, the two techniques provide complementary information with aerosol mass spectrometry providing near universal detection of all aerosol molecules and chemical ionization mass spectrometry with a heated inletmore » providing molecular-level detail of both gases and aerosols. The two techniques operate with atmospheric pressure interfaces and require no matrix addition for ionization, allowing for samples to be investigated in their native state under ambient pressure conditions. We demonstrate the ability of laser ablation-aerosol mass spectrometry-chemical ionization mass spectrometry (LA-AMS-CIMS) to create 2D images of both standard compounds and complex mixtures. Finally, the results suggest that LA-AMS-CIMS, particularly when combined with advanced data analysis methods, could have broad applications in mass spectrometry imaging applications.« less

Laser Ablation-Aerosol Mass Spectrometry-Chemical Ionization Mass Spectrometry for Ambient Surface Imaging

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

Berry, Jennifer L.; Day, Douglas A.; Elseberg, Tim

Mass spectrometry imaging is becoming an increasingly common analytical technique due to its ability to provide spatially resolved chemical information. In this paper, we report a novel imaging approach combining laser ablation with two mass spectrometric techniques, aerosol mass spectrometry and chemical ionization mass spectrometry, separately and in parallel. Both mass spectrometric methods provide the fast response, rapid data acquisition, low detection limits, and high-resolution peak separation desirable for imaging complex samples. Additionally, the two techniques provide complementary information with aerosol mass spectrometry providing near universal detection of all aerosol molecules and chemical ionization mass spectrometry with a heated inletmore » providing molecular-level detail of both gases and aerosols. The two techniques operate with atmospheric pressure interfaces and require no matrix addition for ionization, allowing for samples to be investigated in their native state under ambient pressure conditions. We demonstrate the ability of laser ablation-aerosol mass spectrometry-chemical ionization mass spectrometry (LA-AMS-CIMS) to create 2D images of both standard compounds and complex mixtures. Finally, the results suggest that LA-AMS-CIMS, particularly when combined with advanced data analysis methods, could have broad applications in mass spectrometry imaging applications.« less

Traveling waves for the mass in mass model of granular chains

DOE PAGES

Kevrekidis, Panayotis G.; Stefanov, Atanas G.; Xu, Haitao

2016-06-03

In this work, we consider the mass in mass (or mass with mass) system of granular chains, namely, a granular chain involving additionally an internal (or, respectively, external) resonator. For these chains, we rigorously establish that under suitable “anti-resonance” conditions connecting the mass of the resonator and the speed of the wave, bell-shaped traveling-wave solutions continue to exist in the system, in a way reminiscent of the results proven for the standard granular chain of elastic Hertzian contacts. Finally, we also numerically touch upon settings, where the conditions do not hold, illustrating, in line also with recent experimental work, thatmore » non-monotonic waves bearing non-vanishing tails may exist in the latter case.« less

Traveling waves for the mass in mass model of granular chains

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

Kevrekidis, Panayotis G.; Stefanov, Atanas G.; Xu, Haitao

In this work, we consider the mass in mass (or mass with mass) system of granular chains, namely, a granular chain involving additionally an internal (or, respectively, external) resonator. For these chains, we rigorously establish that under suitable “anti-resonance” conditions connecting the mass of the resonator and the speed of the wave, bell-shaped traveling-wave solutions continue to exist in the system, in a way reminiscent of the results proven for the standard granular chain of elastic Hertzian contacts. Finally, we also numerically touch upon settings, where the conditions do not hold, illustrating, in line also with recent experimental work, thatmore » non-monotonic waves bearing non-vanishing tails may exist in the latter case.« less

Dynamical Mass Generation

NASA Astrophysics Data System (ADS)

Bashir, A.; Raya, A.

2006-09-01

Understanding the origin of mass, in particular that of the fermions, is one of the most uncanny problems which lie at the very frontiers of particle physics. Although the celebrated Standard Model accommodates these masses in a gauge invariant fashion, it fails to predict their values. Moreover, the mass thus generated accounts for only a very small percentage of the mass which permeates the visible universe. Most of the observed mass is accounted for by the strong interactions which bind quarks into protons and neutrons. How does that exactly happen in its quantitative details is still an unsolved mystery. Lattice formulation of quantum chromodynamics (QCD) or continuum studies of its Schwinger-Dyson equations (SDEs) are two of the non-perturbative means to try to unravel how quarks, starting from negligible current masses can acquire enormously large constituent masses to account for the observed proton and neutron masses. Analytical studies of SDEs in this context are extremely hard as one has to resort to truncation schemes whose quantitative reliability can be established only after a very careful analysis. Let alone the far more complicated realm of QCD, arriving at reliable truncation schemes in simpler scenarios such as quantum electrodynamics (QED) has also proved to be a hard nut to crack. In the last years, there has been an increasing group of physicists in Mexico which is taking up the challenge of understanding how the dynamical generation of mass can be understood in a reliable way through SDEs of gauge theories in various contexts such as (i) in arbitrary space-time dimensions d as well as d ⩽ 4, (ii) finite temperatures and (ii) in the presence of magnetic fields. In this article, we summarise some of this work.

Geographic variation in left ventricular mass and mass index: a systematic review.

PubMed

Poppe, K K; Bachmann, M Edgerton; Triggs, C M; Doughty, R N; Whalley, G A

2012-07-01

Left ventricular (LV) hypertrophy, defined as an abnormal increase in LV mass (LVM), is an important prognostic indicator and therapeutic target. LVM is often divided by body surface area to derive indexed mass; however, this does not correctly identify pathological LV hypertrophy in all people, especially when body composition is altered, or in different ethnic groups. We evaluated published ranges of echocardiographic LVM in healthy adult populations from different countries, excluding control groups, and compared them with the American Society of Echocardiography reference ranges. A total of 33 studies met the inclusion criteria. In men and women, there was wide variation in the ranges of LVM with a tendency for the upper limit to increase geographically westward; this variation remained for indexed mass. Several ranges fell outside the upper reference limits: in men, 13 of the mass ranges and 16 of indexed mass; and in women, 8 mass and 16 indexed mass. This review has shown that current guidelines may need revision as some published series suggest that greater LV mass should be considered normal. This may be explained by ethnic differences and supports the need for widely applicable and ethnically diverse reference ranges to be established.

On Defining Mass

ERIC Educational Resources Information Center

Hecht, Eugene

2011-01-01

Though central to any pedagogical development of physics, the concept of mass is still not well understood. Properly defining mass has proven to be far more daunting than contemporary textbooks would have us believe. And yet today the origin of mass is one of the most aggressively pursued areas of research in all of physics. Much of the excitement…

Mapping the core mass function to the initial mass function

NASA Astrophysics Data System (ADS)

Guszejnov, Dávid; Hopkins, Philip F.

2015-07-01

It has been shown that fragmentation within self-gravitating, turbulent molecular clouds (`turbulent fragmentation') can naturally explain the observed properties of protostellar cores, including the core mass function (CMF). Here, we extend recently developed analytic models for turbulent fragmentation to follow the time-dependent hierarchical fragmentation of self-gravitating cores, until they reach effectively infinite density (and form stars). We show that turbulent fragmentation robustly predicts two key features of the initial mass function (IMF). First, a high-mass power-law scaling very close to the Salpeter slope, which is a generic consequence of the scale-free nature of turbulence and self-gravity. We predict the IMF slope (-2.3) is slightly steeper than the CMF slope (-2.1), owing to the slower collapse and easier fragmentation of large cores. Secondly, a turnover mass, which is set by a combination of the CMF turnover mass (a couple solar masses, determined by the `sonic scale' of galactic turbulence, and so weakly dependent on galaxy properties), and the equation of state (EOS). A `soft' EOS with polytropic index γ < 1.0 predicts that the IMF slope becomes `shallow' below the sonic scale, but fails to produce the full turnover observed. An EOS, which becomes `stiff' at sufficiently low surface densities Σgas ˜ 5000 M⊙ pc-2, and/or models, where each collapsing core is able to heat and effectively stiffen the EOS of a modest mass (˜0.02 M⊙) of surrounding gas, are able to reproduce the observed turnover. Such features are likely a consequence of more detailed chemistry and radiative feedback.

Proton mass decomposition

NASA Astrophysics Data System (ADS)

Yang, Yi-Bo; Chen, Ying; Draper, Terrence; Liang, Jian; Liu, Keh-Fei

2018-03-01

We report the results on the proton mass decomposition and also on the related quark and glue momentum fractions. The results are based on overlap valence fermions on four ensembles of Nf = 2 + 1 DWF configurations with three lattice spacings and volumes, and several pion masses including the physical pion mass. With 1-loop pertur-bative calculation and proper normalization of the glue operator, we find that the u, d, and s quark masses contribute 9(2)% to the proton mass. The quark energy and glue field energy contribute 31(5)% and 37(5)% respectively in the MS scheme at µ = 2 GeV. The trace anomaly gives the remaining 23(1)% contribution. The u, d, s and glue momentum fractions in the MS scheme are consistent with the global analysis at µ = 2 GeV.

Atomic masses 1993. The 1993 atomic mass evaluation

NASA Astrophysics Data System (ADS)

Audi, G.; Wapstra, A. H.

1993-11-01

The 1993 atomic mass evaluation by G. Audi and A.H. Wapstra is documented. The resulting data files containing recommended values of atomic masses, obtained by experiment of systematics, and related data such as reaction and separation energies are described. The data files can be obtained through online services from several nuclear data centers or on magnetic tape, free of charge.

Mass-Radius Relationships for Low-Mass Planets: From Iron Planets to Water Planets

NASA Technical Reports Server (NTRS)

Kuchner, Marc

2007-01-01

Transit observations, and radial velocity measurements, have begun to populate the mass radius diagram for extrasolar planets; fubture astrometric measurements and direct images promise more mass and radius information. Clearly, the bulk density of a planet indicates something about a planet s composition--but what? I will attempt to answer this question in general for low-mass planets (mass) using a combination of analytic and numerical calculations, and I will show that all low-mass planets obey a kind of universal mass-radius relationship: an expansion whose first term is M approx. R(sup 3).

No Change of Body Mass, Fat Mass, and Skeletal Muscle Mass in Ultraendurance Swimmers after 12 Hours of Swimming

ERIC Educational Resources Information Center

Knechtle, Beat; Knechtle, Patrizia; Kaul, Rene; Kohler, Gotz

2009-01-01

We evaluated whether ultraendurance swimmers suffer a change of body mass, fat mass, skeletal muscle mass, total body water, and specific gravity of urine during a 12-hr swim in 12 male Caucasian ultraswimmers. Proton nuclear magnetic resonance of urine samples before and after the race was performed to detect alanine, lactate, and…

Evaluation of Mass Filtered, Time Dilated, Time-of-Flight Mass Spectrometry

DTIC Science & Technology

2010-01-01

Figure 4.4: Mass resolution dependence on field for selected actinides and surrogates...45 Figure 4.7: Mass resolution dependence on field for selected actinides and actinide surrogates, modeled with no initial...system. A somewhat better mass resolution would need to be achieved in order to separate hydride molecules in the actinide region. However, the

Fourier transform mass spectrometry.

PubMed

Scigelova, Michaela; Hornshaw, Martin; Giannakopulos, Anastassios; Makarov, Alexander

2011-07-01

This article provides an introduction to Fourier transform-based mass spectrometry. The key performance characteristics of Fourier transform-based mass spectrometry, mass accuracy and resolution, are presented in the view of how they impact the interpretation of measurements in proteomic applications. The theory and principles of operation of two types of mass analyzer, Fourier transform ion cyclotron resonance and Orbitrap, are described. Major benefits as well as limitations of Fourier transform-based mass spectrometry technology are discussed in the context of practical sample analysis, and illustrated with examples included as figures in this text and in the accompanying slide set. Comparisons highlighting the performance differences between the two mass analyzers are made where deemed useful in assisting the user with choosing the most appropriate technology for an application. Recent developments of these high-performing mass spectrometers are mentioned to provide a future outlook.

Mass drivers. 3: Engineering

NASA Technical Reports Server (NTRS)

Arnold, W.; Bowen, S.; Cohen, S.; Fine, K.; Kaplan, D.; Kolm, M.; Kolm, H.; Newman, J.; Oneill, G. K.; Snow, W.

1979-01-01

The last of a series of three papers by the Mass-Driver Group of the 1977 Ames Summer Study is presented. It develops the engineering principles required to implement the basic mass-driver. Optimum component mass trade-offs are derived from a set of four input parameters, and the program used to design a lunar launcher. The mass optimization procedures is then incorporated into a more comprehensive mission optimization program called OPT-4, which evaluates an optimized mass-driver reaction engine and its performance in a range of specified missions. Finally, this paper discusses, to the extent that time permitted, certain peripheral problems: heating effects in buckets due to magnetic field ripple; an approximate derivation of guide force profiles; the mechanics of inserting and releasing payloads; the reaction mass orbits; and a proposed research and development plan for implementing mass drivers.

New Reference Centiles for Left Ventricular Mass Relative to Lean Body Mass in Children.

PubMed

Foster, Bethany J; Khoury, Philip R; Kimball, Thomas R; Mackie, Andrew S; Mitsnefes, Mark

2016-05-01

Echocardiographic measurement of left ventricular (LV) mass is routinely performed in pediatric patients with elevated cardiovascular risk. The complex relationship between heart growth and body growth in children requires normalization of LV mass to determine its appropriateness relative to body size. LV mass is strongly determined by lean body mass (LBM). Using new LBM predictive equations, the investigators generated sex-specific LV mass-for-LBM centile curves for children 5 to 18 years of age. This retrospective study used M-mode echocardiographic data collected from 1995 through 2003 from 939 boys and 771 girls between 5 and 18 years of age (body mass index < 85th percentile for sex and age) to create smoothed sex-specific LV mass-for-LBM reference centile curves using the Lamda Mu Sigma method. The newly developed reference centiles were applied to children with essential hypertension and with chronic kidney disease, groups known to be at high risk for LV hypertrophy (LVH). The identification of LVH using two different normalization approaches was compared: LV mass-for-LBM and LV mass index-for-age percentiles. Among 231 children at risk for LVH, on average, relative LV mass was higher using the LV mass index-for-age percentile method than the LV mass-for-LBM percentile method. LVH was more likely to be diagnosed among overweight children and less likely among thin children. This study provides new LV mass reference centiles expressing LV mass relative to LBM, the strongest determinant of LV mass. These reference centiles may allow more accurate stratification of cardiovascular risk in children. Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Exploring the Relationship between Skeletal Mass and Total Body Mass in Birds.

PubMed

Martin-Silverstone, Elizabeth; Vincze, Orsolya; McCann, Ria; Jonsson, Carl H W; Palmer, Colin; Kaiser, Gary; Dyke, Gareth

2015-01-01

Total body mass (TBM) is known to be related to a number of different osteological features in vertebrates, including limb element measurements and total skeletal mass. The relationship between skeletal mass and TBM in birds has been suggested as a way of estimating the latter in cases where only the skeleton is known (e.g., fossils). This relationship has thus also been applied to other extinct vertebrates, including the non-avian pterosaurs, while other studies have used additional skeletal correlates found in modern birds to estimate TBM. However, most previous studies have used TBM compiled from the literature rather than from direct measurements, producing values from population averages rather than from individuals. Here, we report a new dataset of 487 extant birds encompassing 79 species that have skeletal mass and TBM recorded at the time of collection or preparation. We combine both historical and new data for analyses with phylogenetic control and find a similar and well-correlated relationship between skeletal mass and TBM. Thus, we confirm that TBM and skeletal mass are accurate proxies for estimating one another. We also look at other factors that may have an effect on avian body mass, including sex, ontogenetic stage, and flight mode. While data are well-correlated in all cases, phylogeny is a major control on TBM in birds strongly suggesting that this relationship is not appropriate for estimating the total mass of taxa outside of crown birds, Neornithes (e.g., non-avian dinosaurs, pterosaurs). Data also reveal large variability in both bird skeletal and TBM within single species; caution should thus be applied when using published mass to test direct correlations with skeletal mass and bone lengths.

The Low-Mass Stellar Initial Mass Function: Ultra-Faint Dwarf Galaxies Revisited

NASA Astrophysics Data System (ADS)

Platais, Imants

2017-08-01

The stellar Initial Mass Function plays a critical role in the evolution of the baryonic content of the Universe. The form of the low-mass IMF - stars of mass less than the solar mass - determines the fraction of baryons locked up for a Hubble time, and thus indicates how gas and metals are cycled through galaxies. Inferences from resolved stellar populations, where the low-mass luminosity function and associated IMF can be derived from direct star counts, generally favor an invariant and universal IMF. However, a recent study of ultra-faint dwarf galaxies Hercules and Leo IV indicates a bottom-lite IMF, over a narrow range of stellar mass (only 0.55-0.75 M_sun), correlated with the internal velocity dispersion and/or metallicity. We propose to obtain ultra-deep imaging for a significantly closer ultra-faint dwarf, Bootes I, which will allow us to construct the luminosity function down to M_v=+10 (equivalent to 0.35 solar mass). We will also re-analyze the HST archival observations for the Hercules and Leo IV dwarfs using the same updated techniques as for Bootes I. The combined datasets should provide a reliable answer to the question of how variable is the low-mass stellar IMF.

Application of the mass-spectrometer MASHA for mass-spectrometry and laser-spectroscopy

NASA Astrophysics Data System (ADS)

Rodin, A. M.; Belozerov, A. V.; Dmitriev, S. N.; Oganessian, Yu. Ts.; Sagaidak, R. N.; Salamatin, V. S.; Stepantsov, S. V.; Vanin, D. V.

2010-02-01

We report the present status of the mass-spectrometer MASHA (Mass-Analyzer of Supper Heavy Atoms) designed for determination of the masses of superheavy elements. The mass-spectrometer is connected to the U-400M cyclotron of the Flerov Laboratory for Nuclear Reactions (FLNR) JINR, Dubna. The first experiments on mass-measurements for 112 and 114 elements will be performed in the upcoming 2010. For this purpose a hot catcher, based on a graphite stopper, is constructed. The α-decay of the superheavy nuclides or spontaneous fission products will be detected with a silicon 192 strips detector. The experimental program of future investigations using the technique of a gas catcher is discussed. It should be regarded as an alternative of the classical ISOL technique. The possibilities are considered for using this mass-spectrometer for laser spectroscopy of nuclei far off-stability.

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

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

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

2010-06-07

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

Fourier Transform Mass Spectrometry

PubMed Central

Scigelova, Michaela; Hornshaw, Martin; Giannakopulos, Anastassios; Makarov, Alexander

2011-01-01

This article provides an introduction to Fourier transform-based mass spectrometry. The key performance characteristics of Fourier transform-based mass spectrometry, mass accuracy and resolution, are presented in the view of how they impact the interpretation of measurements in proteomic applications. The theory and principles of operation of two types of mass analyzer, Fourier transform ion cyclotron resonance and Orbitrap, are described. Major benefits as well as limitations of Fourier transform-based mass spectrometry technology are discussed in the context of practical sample analysis, and illustrated with examples included as figures in this text and in the accompanying slide set. Comparisons highlighting the performance differences between the two mass analyzers are made where deemed useful in assisting the user with choosing the most appropriate technology for an application. Recent developments of these high-performing mass spectrometers are mentioned to provide a future outlook. PMID:21742802

Dynamical Mass Generation.

NASA Astrophysics Data System (ADS)

Mendel Horwitz, Roberto Ruben

1982-03-01

In the framework of the Glashow-Weinberg-Salem model without elementary scalar particles, we show that masses for fermions and intermediate vector bosons can be generated dynamically. The mechanism is the formation of fermion-antifermion pseudoscalar bound states of zero total four momentum, which form a condensate in the physical vacuum. The force responsible for the binding is the short distance part of the net Coulomb force due to photon and Z exchange. Fermions and bosons acquire masses through their interaction with this condensate. The neutrinos remain massless because their righthanded components have no interactions. Also the charge -1/3 quarks remain massless because the repulsive force from the Z exchange dominates over the Coulomb force. To correct this, we propose two possible modifications to the theory. One is to cut off the Z exchange at very small distances, so that all fermions except the neutrinos acquire masses, which are then, purely electromagnetic in origin. The other is to introduce an additional gauge boson that couples to all quarks with a pure vector coupling. To make this vector boson unobservable at usual energies, at least two new fermions must couple to it. The vector boson squared masses receive additive contributions from all the fermion squared masses. The photon remains massless and the masses of the Z and W('(+OR -)) bosons are shown to be related through the Weinberg angle in the conventional way. Assuming only three families of fermions, we obtain estimates for the top quark mass.

Study of node and mass sensitivity of resonant mode based cantilevers with concentrated mass loading

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

Zhang, Kewei, E-mail: drzkw@126.com; Chai, Yuesheng; Fu, Jiahui

2015-12-15

Resonant-mode based cantilevers are an important type of acoustic wave based mass-sensing devices. In this work, the governing vibration equation of a bi-layer resonant-mode based cantilever attached with concentrated mass is established by using a modal analysis method. The effects of resonance modes and mass loading conditions on nodes and mass sensitivity of the cantilever were theoretically studied. The results suggested that the node did not shift when concentrated mass was loaded on a specific position. Mass sensitivity of the cantilever was linearly proportional to the square of the point displacement at the mass loading position for all the resonancemore » modes. For the first resonance mode, when mass loading position x{sub c} satisfied 0 < x{sub c} < ∼ 0.3l (l is the cantilever beam length and 0 represents the rigid end), mass sensitivity decreased as the mass increasing while the opposite trend was obtained when mass loading satisfied ∼0.3l ≤ x{sub c} ≤ l. Mass sensitivity did not change when concentrated mass was loaded at the rigid end. This work can provide scientific guidance to optimize the mass sensitivity of a resonant-mode based cantilever.« less

The Use of Gas Chromatography and Mass Spectrometry to Introduce General Chemistry Students to Percent Mass and Atomic Mass Calculations

ERIC Educational Resources Information Center

Pfennig, Brian W.; Schaefer, Amy K.

2011-01-01

A general chemistry laboratory experiment is described that introduces students to instrumental analysis using gas chromatography-mass spectrometry (GC-MS), while simultaneously reinforcing the concepts of mass percent and the calculation of atomic mass. Working in small groups, students use the GC to separate and quantify the percent composition…

Mass balance computation in SAGUARO

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

Baker, B.L.; Eaton, R.R.

1986-12-01

This report describes the development of the mass balance subroutines used with the finite-element code, SAGUARO, which models fluid flow in partially saturated porous media. Derivation of the basic mass storage and mass flux equations is included. The results of the SAGUARO mass-balance subroutine, MASS, are shown to compare favorably with the linked results of FEMTRAN. Implementation of the MASS option in SAGUARO is described. Instructions for use of the MASS option are demonstrated with the three sample cases.

Ultra-high-mass mass spectrometry with charge discrimination using cryogenic detectors

DOEpatents

Frank, Matthias; Mears, Carl A.; Labov, Simon E.; Benner, W. Henry

1999-01-01

An ultra-high-mass time-of-flight mass spectrometer using a cryogenic particle detector as an ion detector with charge discriminating capabilities. Cryogenic detectors have the potential for significantly improving the performance and sensitivity of time-of-flight mass spectrometers, and compared to ion multipliers they exhibit superior sensitivity for high-mass, slow-moving macromolecular ions and can be used as "stop" detectors in time-of-flight applications. In addition, their energy resolving capability can be used to measure the charge state of the ions. Charge discrimination is very valuable in all time-of-flight mass spectrometers. Using a cryogenically-cooled Nb-Al.sub.2 O.sub.3 -Nb superconductor-insulator-superconductor (SIS) tunnel junction (STJ) detector operating at 1.3 K as an ion detector in a time-of-flight mass spectrometer for large biomolecules it was found that the STJ detector has charge discrimination capabilities. Since the cryogenic STJ detector responds to ion energy and does not rely on secondary electron production, as in the conventionally used microchannel plate (MCP) detectors, the cryogenic detector therefore detects large molecular ions with a velocity-independent efficiency approaching 100%.

High-Resolution Mass Spectrometers

NASA Astrophysics Data System (ADS)

Marshall, Alan G.; Hendrickson, Christopher L.

2008-07-01

Over the past decade, mass spectrometry has been revolutionized by access to instruments of increasingly high mass-resolving power. For small molecules up to ˜400 Da (e.g., drugs, metabolites, and various natural organic mixtures ranging from foods to petroleum), it is possible to determine elemental compositions (CcHhNnOoSsPp…) of thousands of chemical components simultaneously from accurate mass measurements (the same can be done up to 1000 Da if additional information is included). At higher mass, it becomes possible to identify proteins (including posttranslational modifications) from proteolytic peptides, as well as lipids, glycoconjugates, and other biological components. At even higher mass (˜100,000 Da or higher), it is possible to characterize posttranslational modifications of intact proteins and to map the binding surfaces of large biomolecule complexes. Here we review the principles and techniques of the highest-resolution analytical mass spectrometers (time-of-flight and Fourier transform ion cyclotron resonance and orbitrap mass analyzers) and describe some representative high-resolution applications.

Inertial Mass

ERIC Educational Resources Information Center

King, Kenneth P.

2007-01-01

The inertial balance is one device that can help students to quantify the quality of inertia--a body's resistance to a change in movement--in more generally understood terms of mass. In this hands-on activity, students use the inertial balance to develop a more quantitative idea of what mass means in an inertial sense. The activity also helps…

Forensic Mass Spectrometry

NASA Astrophysics Data System (ADS)

Hoffmann, William D.; Jackson, Glen P.

2015-07-01

Developments in forensic mass spectrometry tend to follow, rather than lead, the developments in other disciplines. Examples of techniques having forensic potential born independently of forensic applications include ambient ionization, imaging mass spectrometry, isotope ratio mass spectrometry, portable mass spectrometers, and hyphenated chromatography-mass spectrometry instruments, to name a few. Forensic science has the potential to benefit enormously from developments that are funded by other means, if only the infrastructure and personnel existed to adopt, validate, and implement the new technologies into casework. Perhaps one unique area in which forensic science is at the cutting edge is in the area of chemometrics and the determination of likelihood ratios for the evaluation of the weight of evidence. Such statistical techniques have been developed most extensively for ignitable-liquid residue analyses and isotope ratio analysis. This review attempts to capture the trends, motivating forces, and likely impact of developing areas of forensic mass spectrometry, with the caveat that none of this research is likely to have any real impact in the forensic community unless: (a) The instruments developed are turned into robust black boxes with red and green lights for positives and negatives, respectively, or (b) there are PhD graduates in the workforce who can help adopt these sophisticated techniques.

Method for calibrating mass spectrometers

DOEpatents

Anderson, Gordon A [Benton City, WA; Brands, Michael D [Richland, WA; Bruce, James E [Schwenksville, PA; Pasa-Tolic, Ljiljana [Richland, WA; Smith, Richard D [Richland, WA

2002-12-24

A method whereby a mass spectra generated by a mass spectrometer is calibrated by shifting the parameters used by the spectrometer to assign masses to the spectra in a manner which reconciles the signal of ions within the spectra having equal mass but differing charge states, or by reconciling ions having known differences in mass to relative values consistent with those known differences. In this manner, the mass spectrometer is calibrated without the need for standards while allowing the generation of a highly accurate mass spectra by the instrument.

Estimating initial contaminant mass based on fitting mass-depletion functions to contaminant mass discharge data: Testing method efficacy with SVE operations data

NASA Astrophysics Data System (ADS)

Mainhagu, J.; Brusseau, M. L.

2016-09-01

The mass of contaminant present at a site, particularly in the source zones, is one of the key parameters for assessing the risk posed by contaminated sites, and for setting and evaluating remediation goals and objectives. This quantity is rarely known and is challenging to estimate accurately. This work investigated the efficacy of fitting mass-depletion functions to temporal contaminant mass discharge (CMD) data as a means of estimating initial mass. Two common mass-depletion functions, exponential and power functions, were applied to historic soil vapor extraction (SVE) CMD data collected from 11 contaminated sites for which the SVE operations are considered to be at or close to essentially complete mass removal. The functions were applied to the entire available data set for each site, as well as to the early-time data (the initial 1/3 of the data available). Additionally, a complete differential-time analysis was conducted. The latter two analyses were conducted to investigate the impact of limited data on method performance, given that the primary mode of application would be to use the method during the early stages of a remediation effort. The estimated initial masses were compared to the total masses removed for the SVE operations. The mass estimates obtained from application to the full data sets were reasonably similar to the measured masses removed for both functions (13 and 15% mean error). The use of the early-time data resulted in a minimally higher variation for the exponential function (17%) but a much higher error (51%) for the power function. These results suggest that the method can produce reasonable estimates of initial mass useful for planning and assessing remediation efforts.

Mass spectrometer calibration standard

NASA Technical Reports Server (NTRS)

Ross, D. S.

1978-01-01

Inert perfluorinated alkane and alkyl ethers mixture is used to calibrate mass spectrometer. Noncontaminating, commercially-available liquid provides series of reproducible reference peaks over broad mass spectrum that ranges over mass numbers from 1 to 200.

The 2012 Atomic Mass Evaluation and the Mass Tables

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

Audi, G., E-mail: amdc.audi@gmail.com; Wang, M.; MPI-K, D-69117 Heidelberg

The new evaluation of the Atomic Masses, Ame2012, has just been released. It represents a major step in the history of the 60 year old Atomic Mass Evaluation based on the method developed by Wapstra. This new publication includes all material available to date. Some of the policies and procedures used in our evaluation are reported, together with an illustration of one specially difficult case, the energy available for the {sup 102}Pd double-electron capture. The observation of the mass surface reveals many important new features. We illustrate this statement by the double magicity of {sup 270}Hs at N = 162more » and Z = 108.« less

[Small renal mass].

PubMed

Prokofiev, D; Kreutzer, N; Kress, A; Wissing, F; Pfeifer, H; Stolzenburg, J-U; Dietel, A; Schwalenberg, T; Do, M; Truß, M C

2012-10-01

The frequent application of ultrasound and radiological imaging for non-urological indications in recent years has resulted in an increase in the diagnosis of small renal masses. The treatment options for patients with a small renal mass include active surveillance, surgery (both open and minimally invasive) as well as ablative techniques. As there is a risk for metastatic spread even in small renal masses surgical extirpation remains the treatment of choice in most patients. Ablative procedures, such as cryoablation and radiofrequency ablation are appropriate for old and multi-morbid patients who require active treatment of a small renal mass. Active surveillance is an alternative for high-risk patients. Meticulous patient selection by the urologist and patient preference will determine the choice of treatment option in the future.

Probabilistic Mass Growth Uncertainties

NASA Technical Reports Server (NTRS)

Plumer, Eric; Elliott, Darren

2013-01-01

Mass has been widely used as a variable input parameter for Cost Estimating Relationships (CER) for space systems. As these space systems progress from early concept studies and drawing boards to the launch pad, their masses tend to grow substantially, hence adversely affecting a primary input to most modeling CERs. Modeling and predicting mass uncertainty, based on historical and analogous data, is therefore critical and is an integral part of modeling cost risk. This paper presents the results of a NASA on-going effort to publish mass growth datasheet for adjusting single-point Technical Baseline Estimates (TBE) of masses of space instruments as well as spacecraft, for both earth orbiting and deep space missions at various stages of a project's lifecycle. This paper will also discusses the long term strategy of NASA Headquarters in publishing similar results, using a variety of cost driving metrics, on an annual basis. This paper provides quantitative results that show decreasing mass growth uncertainties as mass estimate maturity increases. This paper's analysis is based on historical data obtained from the NASA Cost Analysis Data Requirements (CADRe) database.

Alternative mass reference standards for direct analysis in real time mass spectrometry.

PubMed

Cody, Robert B; Dane, A John

2016-05-30

Mass spectra were acquired with the Direct Analysis in Real Time (DART®) ion source for an amine-terminated polyether used as positive-ion mass reference standards and for several fluorinated materials commonly used as negative-ion reference standards for mass spectrometry. A commercial time-of-flight mass spectrometer equipped with a DART ion source was used for all measurements. Mass reference standards deposited onto the sealed end of a glass melting point tube were suspended in the DART gas stream for analysis. A polyetheramine (Jeffamine® M-600) produced intense peaks corresponding to protonated molecules. Perfluorotributylamine (PFTBA), and perfluorotripentylamine, gave useful reference spectra for different m/z ranges. DART mass spectra of Ultramark 1621® resembled those previously reported for Fast Atom Bombardment (FAB) and Electrospray Ionization (ESI). Fomblin®Y, a fluorinated ether, was the most useful negative-ion reference standard of the materials tested. The material is commercially available, inexpensive, and provides reference peaks covering the m/z range 85 to >3000. Jeffamine-M600 was found to be a convenient alternative to polyethers such as polyethylene glycol (PEG) for DART positive-ion mass calibration. Fomblin Y was suitable for use as a negative-ion reference standard. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The dependence of halo mass on galaxy size at fixed stellar mass using weak lensing

NASA Astrophysics Data System (ADS)

Charlton, Paul J. L.; Hudson, Michael J.; Balogh, Michael L.; Khatri, Sumeet

2017-12-01

Stellar mass has been shown to correlate with halo mass, with non-negligible scatter. The stellar mass-size and luminosity-size relationships of galaxies also show significant scatter in galaxy size at fixed stellar mass. It is possible that, at fixed stellar mass and galaxy colour, the halo mass is correlated with galaxy size. Galaxy-galaxy lensing allows us to measure the mean masses of dark matter haloes for stacked samples of galaxies. We extend the analysis of the galaxies in the CFHTLenS catalogue by fitting single Sérsic surface brightness profiles to the lens galaxies in order to recover half-light radius values, allowing us to determine halo masses for lenses according to their size. Comparing our halo masses and sizes to baselines for that stellar mass yields a differential measurement of the halo mass-galaxy size relationship at fixed stellar mass, defined as Mh(M_{*}) ∝ r_{eff}^{η }(M_{*}). We find that, on average, our lens galaxies have an η = 0.42 ± 0.12, i.e. larger galaxies live in more massive dark matter haloes. The η is strongest for high-mass luminous red galaxies. Investigation of this relationship in hydrodynamical simulations suggests that, at a fixed M*, satellite galaxies have a larger η and greater scatter in the Mh and reff relationship compared to central galaxies.

Low Masses and High Redshifts: The Evolution of the Mass-Metallicity Relation

NASA Technical Reports Server (NTRS)

Henry, Alaina; Scarlata, Claudia; Dominguez, Alberto; Malkan, Matthew; Martin, Crystal L.; Siana, Brian; Atek, Hakim; Bedregal, Alejandro G.; Colbert, James W.; Rafelski, Marc;

Metabolic Profiling of Dendrobium officinale in Response to Precursors and Methyl Jasmonate

PubMed Central

Jiao, Chunyan; Song, Cheng; Zheng, Siyan; Zhu, Yingpeng; Jin, Qing; Cai, Yongping; Lin, Yi

2018-01-01

Alkaloids are the main active ingredients in the medicinal plant Dendrobium officinale. Based on the published genomic and transcriptomic data, a proposed terpenoid indole alkaloid (TIA) biosynthesis pathway may be present in D. officinale. In this study, protocorm-like bodies (PLBs) with a high-yielding production of alkaloids were obtained by the optimization of tryptophan, secologanin and methyl jasmonate (MeJA) treatment. The results showed that the total alkaloid content was 2.05 times greater than that of the control group when the PLBs were fed with 9 µM tryptophan, 6 µM secologanin and 100 µM MeJA after 36 days. HPLC analysis showed that strictosidine synthase (STR) activity also increased in the treated plants. A total of 78 metabolites were identified using gas chromatography-mass spectrometry (GC-MS) in combination with liquid chromatography-mass spectrometry (LC-MS) methods; 29 differential metabolites were identified according to the multivariate statistical analysis. Among them, carapanaubine, a kind of TIA, exhibited dramatically increased levels. In addition, a possible underlying process of the metabolic flux from related metabolism to the TIA biosynthetic pathway was enhanced. These results provide a comprehensive view of the metabolic changes related to alkaloid biosynthesis, especially TIA biosynthesis, in response to tryptophan, secologanin and MeJA treatment. PMID:29510516

Trap-induced mass declines in small mammals: Mass as a population index

Treesearch

Dean E. Pearson; Yvette K. Ortega; Leonard F. Ruggiero

2003-01-01

Body mass is routinely used as an index of physical condition for comparing small-mammal populations. However, trapping effects on animals may undermine the effectiveness of body mass as an index of population health. We examined the effects of live-trapping on body mass of 3 small-mammal species: deer mice (Peromyscus maniculatus), southern red-...

Fourier Transform Mass Spectrometry.

ERIC Educational Resources Information Center

Gross, Michael L.; Rempel, Don L.

1984-01-01

Discusses the nature of Fourier transform mass spectrometry and its unique combination of high mass resolution, high upper mass limit, and multichannel advantage. Examines its operation, capabilities and limitations, applications (ion storage, ion manipulation, ion chemistry), and future applications and developments. (JN)

Linear Proof-Mass Actuator

NASA Technical Reports Server (NTRS)

Holloway, Sidney E., III; Crossley, Edward A.; Miller, James B.; Jones, Irby W.; Davis, C. Calvin; Behun, Vaughn D.; Goodrich, Lewis R., Sr.

1995-01-01

Linear proof-mass actuator (LPMA) is friction-driven linear mass actuator capable of applying controlled force to structure in outer space to damp out oscillations. Capable of high accelerations and provides smooth, bidirectional travel of mass. Design eliminates gears and belts. LPMA strong enough to be used terrestrially where linear actuators needed to excite or damp out oscillations. High flexibility designed into LPMA by varying size of motors, mass, and length of stroke, and by modifying control software.

1986-87 atomic mass predictions

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

Haustein, P.E.

A project to perform a comprehensive update of the atomic mass predictions has recently been concluded and will be published shortly in Atomic Data and Nuclear Data Tables. The project evolved from an ongoing comparison between available mass predictions and reports of newly measured masses of isotopes throughout the mass surface. These comparisons have highlighted a variety of features in current mass models which are responsible for predictions that diverge from masses determined experimentally. The need for a comprehensive update of the atomic mass predictions was therefore apparent and the project was organized and began at the last mass conferencemore » (AMCO-VII). Project participants included: Pape and Anthony; Dussel, Caurier and Zuker; Moeller and Nix; Moeller, Myers, Swiatecki and Treiner; Comay, Kelson, and Zidon; Satpathy and Nayak; Tachibana, Uno, Yamada and Yamada; Spanier and Johansson; Jaenecke and Masson; and Wapstra, Audi and Hoekstra. An overview of the new atomic mass predictions may be obtained by written request.« less

The Higgs mass coincidence problem: why is the Higgs mass ?

NASA Astrophysics Data System (ADS)

Torrente-Lujan, E.

2014-02-01

In the light of the recent LHC boson discovery, we present a phenomenological evaluation of the ratio , from the LHC combined value, we get () This value is close to 1 with a precision of the order . Similarly we evaluate the ratio . From the up-to-date mass values we get . The Higgs mass is numerically close (at the level) to the . From these relations we can write any two mass ratios as a function of, exclusively, the Weinberg angle (with a precision of the order of or better): For example: , . In the limit all the masses would become equal . We review the theoretical situation of this ratio in the SM and beyond. In the SM these relations are rather stable under RGE pointing out to some underlying UV symmetry. In the SM such a ratio hints for a non-casual relation of the type with . Moreover the existence of relations could be interpreted as a hint for a role of the custodial symmetry, together with other unknown mechanism. Without a symmetry at hand to explain then in the SM, there arises a Higgs mass coincidence problem, why the ratios are so close to one, can we find a mechanism that naturally gives , ?

Mass discharge assessment at a brominated DNAPL site: Effects of known DNAPL source mass removal

NASA Astrophysics Data System (ADS)

Johnston, C. D.; Davis, G. B.; Bastow, T. P.; Woodbury, R. J.; Rao, P. S. C.; Annable, M. D.; Rhodes, S.

2014-08-01

Management and closure of contaminated sites is increasingly being proposed on the basis of mass flux of dissolved contaminants in groundwater. Better understanding of the links between source mass removal and contaminant mass fluxes in groundwater would allow greater acceptance of this metric in dealing with contaminated sites. Our objectives here were to show how measurements of the distribution of contaminant mass flux and the overall mass discharge emanating from the source under undisturbed groundwater conditions could be related to the processes and extent of source mass depletion. In addition, these estimates of mass discharge were sought in the application of agreed remediation targets set in terms of pumped groundwater quality from offsite wells. Results are reported from field studies conducted over a 5-year period at a brominated DNAPL (tetrabromoethane, TBA; and tribromoethene, TriBE) site located in suburban Perth, Western Australia. Groundwater fluxes (qw; L3/L2/T) and mass fluxes (Jc; M/L2/T) of dissolved brominated compounds were simultaneously estimated by deploying Passive Flux Meters (PFMs) in wells in a heterogeneous layered aquifer. PFMs were deployed in control plane (CP) wells immediately down-gradient of the source zone, before (2006) and after (2011) 69-85% of the source mass was removed, mainly by groundwater pumping from the source zone. The high-resolution (26-cm depth interval) measures of qw and Jc along the source CP allowed investigation of the DNAPL source-zone architecture and impacts of source mass removal. Comparable estimates of total mass discharge (MD; M/T) across the source zone CP reduced from 104 g day- 1 to 24-31 g day- 1 (70-77% reductions). Importantly, this mass discharge reduction was consistent with the estimated proportion of source mass remaining at the site (15-31%). That is, a linear relationship between mass discharge and source mass is suggested. The spatial detail of groundwater and mass flux distributions also

Mass discharge assessment at a brominated DNAPL site: Effects of known DNAPL source mass removal.

PubMed

Johnston, C D; Davis, G B; Bastow, T P; Woodbury, R J; Rao, P S C; Annable, M D; Rhodes, S

2014-08-01

Management and closure of contaminated sites is increasingly being proposed on the basis of mass flux of dissolved contaminants in groundwater. Better understanding of the links between source mass removal and contaminant mass fluxes in groundwater would allow greater acceptance of this metric in dealing with contaminated sites. Our objectives here were to show how measurements of the distribution of contaminant mass flux and the overall mass discharge emanating from the source under undisturbed groundwater conditions could be related to the processes and extent of source mass depletion. In addition, these estimates of mass discharge were sought in the application of agreed remediation targets set in terms of pumped groundwater quality from offsite wells. Results are reported from field studies conducted over a 5-year period at a brominated DNAPL (tetrabromoethane, TBA; and tribromoethene, TriBE) site located in suburban Perth, Western Australia. Groundwater fluxes (qw; L(3)/L(2)/T) and mass fluxes (Jc; M/L(2)/T) of dissolved brominated compounds were simultaneously estimated by deploying Passive Flux Meters (PFMs) in wells in a heterogeneous layered aquifer. PFMs were deployed in control plane (CP) wells immediately down-gradient of the source zone, before (2006) and after (2011) 69-85% of the source mass was removed, mainly by groundwater pumping from the source zone. The high-resolution (26-cm depth interval) measures of qw and Jc along the source CP allowed investigation of the DNAPL source-zone architecture and impacts of source mass removal. Comparable estimates of total mass discharge (MD; M/T) across the source zone CP reduced from 104gday(-1) to 24-31gday(-1) (70-77% reductions). Importantly, this mass discharge reduction was consistent with the estimated proportion of source mass remaining at the site (15-31%). That is, a linear relationship between mass discharge and source mass is suggested. The spatial detail of groundwater and mass flux distributions

Non-Target Screening of Veterinary Drugs Using Tandem Mass Spectrometry on SmartMass

NASA Astrophysics Data System (ADS)

Xia, Bing; Liu, Xin; Gu, Yu-Cheng; Zhang, Zhao-Hui; Wang, Hai-Yan; Ding, Li-Sheng; Zhou, Yan

2013-05-01

Non-target screening of veterinary drugs using tandem mass spectrometric data was performed on the SmartMass platform. This newly developed software uses the characteristic fragmentation patterns (CFP) to identify chemicals, especially those containing particular substructures. A mixture of 17 sulfonamides was separated by ultra performance liquid chromatography (UPLC), and SmartMass was used to process the tandem mass spectrometry (MS/MS) data acquired on an Orbitrap mass spectrometer. The data were automatically extracted, and each sulfonamide was recognized and analyzed with a prebuilt analysis rule. By using this software, over 98 % of the false candidate structures were eliminated, and all the correct structures were found within the top 10 of the ranking lists. Furthermore, SmartMass could also be used to identify slightly modified contraband drugs and metabolites with simple prebuilt rules. [Figure not available: see fulltext.

Body mass index

MedlinePlus

... page: //medlineplus.gov/ency/article/007196.htm Body mass index To use the sharing features on this ... your height is to figure out your body mass index (BMI). You and your health care provider ...

Condensed-Phase Processes during Solid Propellant Combustion. Part 2: Chemical and Microscopic Examination of Conductively Quenched Samples of RDX, XM39, JA2, M30, and HMX-Binder Compositions

DTIC Science & Technology

1992-05-01

combustion of most of the propellants, with the possible exception of JA2; scanning electron microcope examination shows the existence of a liquid layer but... compounds are similar (Fifer et Sl. 1985; Hoffsommer, Glover, and Elban 1985), the relative Intensities In Table 2 should provide rough, order-of...top of the liquid layer. In addition, the HPLC chromatograms contained a number of very weak, unknown peaks apparently corresponding to compounds

Illustrating the Basic Functioning of Mass Analyzers in Mass Spectrometers with Ball-Rolling Mechanisms

ERIC Educational Resources Information Center

Horikoshi, Ryo; Takeiri, Fumitaka; Mikita, Riho; Kobayashi, Yoji; Kageyama, Hiroshi

2017-01-01

A unique demonstration with ball-rolling mechanisms has been developed to illustrate the basic principles of mass analyzers as components of mass spectrometers. Three ball-rolling mechanisms mimicking the currently used mass analyzers (i.e., a quadrupole mass filter, a magnetic sector, and a time-of- flight) have been constructed. Each mechanism…

A mass spectrometry primer for mass spectrometry imaging

PubMed Central

Rubakhin, Stanislav S.; Sweedler, Jonathan V.

2011-01-01

Mass spectrometry imaging (MSI), a rapidly growing subfield of chemical imaging, employs mass spectrometry (MS) technologies to create single- and multi-dimensional localization maps for a variety of atoms and molecules. Complimentary to other imaging approaches, MSI provides high chemical specificity and broad analyte coverage. This powerful analytical toolset is capable of measuring the distribution of many classes of inorganics, metabolites, proteins and pharmaceuticals in chemically and structurally complex biological specimens in vivo, in vitro, and in situ. The MSI approaches highlighted in this Methods in Molecular Biology volume provide flexibility of detection, characterization, and identification of multiple known and unknown analytes. The goal of this chapter is to introduce investigators who may be unfamiliar with MS to the basic principles of the mass spectrometric approaches as used in MSI. In addition to guidelines for choosing the most suitable MSI method for specific investigations, cross-references are provided to the chapters in this volume that describe the appropriate experimental protocols. PMID:20680583

Mass spectrometry and tandem mass spectrometry of citrus limonoids.

PubMed

Tian, Qingguo; Schwartz, Steven J

2003-10-15

Methods for atmospheric pressure chemical ionization tandem mass spectrometry (APCI-MS/MS) of citrus limonoid aglycones and electrospray ionization tandem mass spectrometry (ESI-MS/MS) of limonoid glucosides are reported. The fragmentation patterns of four citrus limonoid aglycones (limonin, nomilin, obacunone, and deacetylnomilin) and six limonoid glucosides, that is, limonin 17-beta-D-glucopyranoside (LG), nomilin 17-beta-D-glucopyranoside (NG), nomilinic acid 17-beta-D-glucopyranoside (NAG), deacetyl nomilinic acid 17-beta-D-glucopyranoside (DNAG), obacunone 17-beta-D-glucopyranoside (OG), and obacunoic acid 17-beta-D-glucopyranoside (OAG) were investigated using a quadruple mass spectrometer in low-energy collisionally activated dissociation (CAD). The four limonoid aglycones and four limonoid glucosides (LG, OG, NAG, and DNAG) were purified from citrus seeds; the other two limonoid glucosides (NG and OAG) were tentatively identified in the crude extract of grapefruit seeds by ESI mass spectrometry in both positive and negative ion analysis. Ammonium hydroxide or acetic acid was added to the mobile phase to facilitate ionization. During positive ion APCI analysis of limonoid aglycones, protonated molecular ion, [M + H]+, or adduct ion, [M + NH3 + H]-, was formed as base peaks when ammonium hydroxide was added to the mobile phase. Molecular anions or adduct ions with acetic acid ([M + HOAc - H] and [M + HOAc]-) or a deprotonated molecular ion were produced during negative ion APCI analysis of limonoid aglycones, depending on the mobile-phase modifier used. Positive ion ESI-MS of limonoid glucosides produced adduct ions of [M + H + NH3]+, [M + Na]+, and [M + K]+ when ammonium hydroxide was added to the mobile phase. After collisionally activated dissociation (CAD) of the limonoid aglycone molecular ions in negative ion APCI analysis, fragment ions indicated structural information of the precursor ions, showing the presence of methyl, carboxyl, and oxygenated ring

Neutrino mass sum-rule

NASA Astrophysics Data System (ADS)

Damanik, Asan

2018-03-01

Neutrino mass sum-rele is a very important research subject from theoretical side because neutrino oscillation experiment only gave us two squared-mass differences and three mixing angles. We review neutrino mass sum-rule in literature that have been reported by many authors and discuss its phenomenological implications.

Photon Mass, Graviton Mass: Zero or Not?

NASA Astrophysics Data System (ADS)

Scharff Goldhaber, Alfred; Nieto, Michael Martin

2007-04-01

Testing for deviations from simple laws is a time-honored part of physics research. In electricity and magnetism the first approach to such testing, from the eighteenth century well into the twentieth, was to look for departures from -2 of the power of distance between two electric charges or two magnetic poles determining the force between them. Absent a particular length scale, this was a natural choice for parameterizing possible deviations from the simple and esthetic inverse square law. With the advent of relativity and quantum mechanics, and the realization that certain phenomena of light can be described in terms of photon particles, it became appealing to ask if these particles might have a non-zero mass, and Proca found the appropriate modification of the Maxwell equations. Despite the particle-motion origin of this idea, the most powerful way to constrain the size of a possible photon mass is by setting a lower bound on the Compton wavelength, by looking at static electric and especially magnetic fields over increasing length scales. For gravity similar statements apply, but graviton mass is theoretically questionable, and observed phenomena imply either additional sources or departures from Einstein's general relativity.

Body fat mass and lean mass as predictors of survival in hemodialysis patients.

PubMed

Kakiya, R; Shoji, T; Tsujimoto, Y; Tatsumi, N; Hatsuda, S; Shinohara, K; Kimoto, E; Tahara, H; Koyama, H; Emoto, M; Ishimura, E; Miki, T; Tabata, T; Nishizawa, Y

2006-08-01

A higher body mass index (BMI) is a predictor of better survival in hemodialysis patients, although the relative importance of body fat and lean mass has not been examined in the dialysis population. We performed an observational cohort study in 808 patients with end-stage renal disease on maintenance hemodialysis. At baseline, fat mass was measured by dual-energy X-ray absorptiometry and expressed as fat mass index (FMI; kg/m2). Lean mass index (LMI) was defined as BMI minus FMI. During the mean follow-up period of 53 months, 147 deaths, including 62 cardiovascular (CV) and 85 non-CV fatal events, were recorded. In univariate analysis, LMI was not significantly associated with CV or non-CV death, whereas a higher FMI was predictive of lower risk for non-CV death. Analyses with multivariate Cox models, which took other confounding variables as covariates, indicated the independent associations between a higher LMI and a lower risk of CV death, as well as between a higher FMI and a lower risk of non-CV death. These results indicate that increased fat mass and lean mass were both conditions associated with better outcomes in the dialysis population.

SINTERED REFRACTORY MASS

DOEpatents

Williams, A.E.

1955-09-01

A method is given for joining sintered masses of refractory compounds. It consists in maintaining the masses in contact with each other by application of a moderate pressure, while they are at sintering temperature. The sintered masses are subjected to am applied pressure of about 1/2 to 1 ton per square inch of the surface in contact for about 10 minutes, and the temperature employed may be fropn about 1400 deg C to 2000 deg C. Refractory oxides to which the invention may be applied are beryllia, alumina, thoria, and magnesia.

Lunar orbital mass spectrometer experiment

NASA Technical Reports Server (NTRS)

Lord, W. P.

1971-01-01

The design, development, manufacture, test and calibration of five lunar orbital mass spectrometers with the four associated ground support equipment test sets are discussed. A mass spectrometer was installed in the Apollo 15 and one in the Apollo 16 Scientific Instrument Module within the Service Module. The Apollo 15 mass spectrometer was operated with collection of 38 hours of mass spectra data during lunar orbit and 50 hours of data were collected during transearth coast. The Apollo 16 mass spectrometer was operated with collection of 76 hours of mass spectra data during lunar orbit. However, the Apollo 16 mass spectrometer was ejected into lunar orbit upon malfunction of spacecraft boom system just prior to transearth insection and no transearth coast data was possible.

Stellar Initial Mass Function: Trends With Galaxy Mass And Radius

NASA Astrophysics Data System (ADS)

Parikh, Taniya

2017-06-01

There is currently no consensus about the exact shape and, in particular, the universality of the stellar initial mass function (IMF). For massive galaxies, it has been found that near-infrared (NIR) absorption features, which are sensitive to the ratio of dwarf to giant stars, deviate from a Milky Way-like IMF; their modelling seems to require a larger fraction of low mass stars. There are now increasing results looking at whether the IMF varies not only with galaxy mass, but also radially within galaxies. The SDSS-IV/MaNGA integral-field survey will provide spatially resolved spectroscopy for 10,000 galaxies at R 2000 from 360-1000nm. Spectra of early-type galaxies were stacked to achieve high S/N which is particularly important for features in the NIR. Trends with galaxy radius and mass were compared to stellar population models for a range of absorption features in order to separate degeneracies due to changes in stellar population parameters, such as age, metallicity and element abundances, with potential changes in the IMF. Results for 611 galaxies show that we do not require an IMF steeper than Kroupa as a function of galaxy mass or radius based on the NaI index. The Wing-Ford band hints towards a steeper IMF at large radii however we do not have reliable measurements for the most massive galaxies.

Low-mass stars in globular clusters. III. The mass function of 47 Tucanae.

NASA Astrophysics Data System (ADS)

de Marchi, G.; Paresce, F.

1995-12-01

We have used the WFPC2 on board HST to investigate the stellar population in a field located 4'6 E of the center of the globular cluster 47 Tuc (NGC 104), close to the half-mass radius, through wide band imaging at 606 and 812nm. A total of ~3000 stars are accurately classified by two-color photometry to form a color-magnitude diagram extending down to a limiting magnitude m_814_=~m_I_=~24. A rich cluster main sequence is detected spanning the range from m_814_=~18 through m_814_=~23, where it spreads considerably due to the increasing photometric uncertainty and galaxy contamination. A secondary sequence of objects is also detected, parallel to the main sequence, as expected for a population of binary stars. The measured binary fraction in the range 195%. The main sequence luminosity function obtained from the observed CMD increases with decreasing luminosity following a power-law trend with index α=~0.15 in the range 5mass-luminosity relation for this metallicity, the resultant mass function shows a power-law increase in numbers for decreasing masses in the range 0.8-0.3Msun_ with a slope α=~1.5, but then flattens out in the 0.3-0.15Msun_ range. The comparison of the mass function of 47 Tuc with that of NGC 6397 (Paper I) and of M 15 (Paper II), previously investigated with the same instrumentation, suggests that the stellar population near the half-mass radius of these clusters should not be very sensitive to either internal or externally-driven dynamical processes. The difference between their mass functions could then be attributed to metallicity, reflecting an intrinsic difference in their initial mass functions, unless mass-segregation is stronger in 47 Tuc than in the other two clusters. This latter circumstance could be due, for instance, to the large number

Reevaluating the Mass-Radius Relation for Low-mass, Main-sequence Stars

NASA Astrophysics Data System (ADS)

Feiden, Gregory A.; Chaboyer, Brian

2012-09-01

We examine the agreement between the observed and theoretical low-mass (<0.8 M ⊙) stellar main-sequence mass-radius relationship by comparing detached eclipsing binary (DEB) data with a new, large grid of stellar evolution models. The new grid allows for a realistic variation in the age and metallicity of the DEB population, characteristic of the local galactic neighborhood. Overall, our models do a reasonable job of reproducing the observational data. A large majority of the models match the observed stellar radii to within 4%, with a mean absolute error of 2.3%. These results represent a factor of two improvement compared to previous examinations of the low-mass mass-radius relationship. The improved agreement between models and observations brings the radius deviations within the limits imposed by potential starspot-related uncertainties for 92% of the stars in our DEB sample.

The Neutron Star Mass Distribution

NASA Astrophysics Data System (ADS)

Kiziltan, Bülent; Kottas, Athanasios; De Yoreo, Maria; Thorsett, Stephen E.

2013-11-01

In recent years, the number of pulsars with secure mass measurements has increased to a level that allows us to probe the underlying neutron star (NS) mass distribution in detail. We critically review the radio pulsar mass measurements. For the first time, we are able to analyze a sizable population of NSs with a flexible modeling approach that can effectively accommodate a skewed underlying distribution and asymmetric measurement errors. We find that NSs that have evolved through different evolutionary paths reflect distinctive signatures through dissimilar distribution peak and mass cutoff values. NSs in double NS and NS-white dwarf (WD) systems show consistent respective peaks at 1.33 M ⊙ and 1.55 M ⊙, suggesting significant mass accretion (Δm ≈ 0.22 M ⊙) has occurred during the spin-up phase. The width of the mass distribution implied by double NS systems is indicative of a tight initial mass function while the inferred mass range is significantly wider for NSs that have gone through recycling. We find a mass cutoff at ~2.1 M ⊙ for NSs with WD companions, which establishes a firm lower bound for the maximum NS mass. This rules out the majority of strange quark and soft equation of state models as viable configurations for NS matter. The lack of truncation close to the maximum mass cutoff along with the skewed nature of the inferred mass distribution both enforce the suggestion that the 2.1 M ⊙ limit is set by evolutionary constraints rather than nuclear physics or general relativity, and the existence of rare supermassive NSs is possible.

Aptamer-facilitated mass cytometry.

PubMed

Mironov, Gleb G; Bouzekri, Alexandre; Watson, Jessica; Loboda, Olga; Ornatsky, Olga; Berezovski, Maxim V

2018-05-01

Mass cytometry is a novel cell-by-cell analysis technique, which uses elemental tags instead of fluorophores. Sample cells undergo rapid ionization in inductively coupled plasma and the ionized elemental tags are then analyzed by means of time-of-flight mass spectrometry. Benefits of the mass cytometry approach are in no need for compensation, the high number of detection channels (up to 100) and low background noise. In this work, we applied a biotinylated aptamer against human PTK7 receptor for characterization of positive (human acute lymphoblastic leukemia) and negative (human Burkitt's lymphoma) cells by a mass cytometry instrument. Our proof of principal experiments showed that biotinylated aptamers in conjunction with metal-labeled neutravidin can be successfully utilized for mass cytometry experiments at par with commercially available antibodies. Graphical abstract Biotinylated aptamers in conjunction with metal-labeled neutravidin bind to cell biomarkers, and then injected into the inductively coupled plasma (ICP) source, where cells are vaporized, atomized, and ionized in the plasma for subsequent mass spectrometry (MS) analysis of lanthanide metals.

Extending MAM5 Meta-Model and JaCalIV E Framework to Integrate Smart Devices from Real Environments

PubMed Central

2016-01-01

This paper presents the extension of a meta-model (MAM5) and a framework based on the model (JaCalIVE) for developing intelligent virtual environments. The goal of this extension is to develop augmented mirror worlds that represent a real and virtual world coupled, so that the virtual world not only reflects the real one, but also complements it. A new component called a smart resource artifact, that enables modelling and developing devices to access the real physical world, and a human in the loop agent to place a human in the system have been included in the meta-model and framework. The proposed extension of MAM5 has been tested by simulating a light control system where agents can access both virtual and real sensor/actuators through the smart resources developed. The results show that the use of real environment interactive elements (smart resource artifacts) in agent-based simulations allows to minimize the error between simulated and real system. PMID:26926691

Extending MAM5 Meta-Model and JaCalIV E Framework to Integrate Smart Devices from Real Environments.

PubMed

Rincon, J A; Poza-Lujan, Jose-Luis; Julian, V; Posadas-Yagüe, Juan-Luis; Carrascosa, C

2016-01-01

This paper presents the extension of a meta-model (MAM5) and a framework based on the model (JaCalIVE) for developing intelligent virtual environments. The goal of this extension is to develop augmented mirror worlds that represent a real and virtual world coupled, so that the virtual world not only reflects the real one, but also complements it. A new component called a smart resource artifact, that enables modelling and developing devices to access the real physical world, and a human in the loop agent to place a human in the system have been included in the meta-model and framework. The proposed extension of MAM5 has been tested by simulating a light control system where agents can access both virtual and real sensor/actuators through the smart resources developed. The results show that the use of real environment interactive elements (smart resource artifacts) in agent-based simulations allows to minimize the error between simulated and real system.

Mass Spectrometry for the Masses

ERIC Educational Resources Information Center

Persinger, Jared D.; Hoops, Geoffrey, C.; Samide, Michael J.

2004-01-01

A simple, qualitative experiment is developed for implementation, where the gas chromatography-mass spectrometry (GC-MS) plays an important role, into the laboratory curriculum of a chemistry course designed for nonscience majors. This laboratory experiment is well suited for the students as it helps them to determine the validity of their…

Deflected Propagation of Coronal Mass Ejections: One of the Key Issues in Space Weather Forecasting

NASA Astrophysics Data System (ADS)

Wang, Y.; Shen, C.; Zhuang, B.; Pan, Z.

2016-12-01

As the most important driver of severe space weather, coronal mass ejections (CMEs) and their geoeffectiveness have been studied intensively. Previous statistical studies have shown that not all the front-side halo CMEs are geoeffective, and not all non-recurrent geomagnetic storms can be tracked back to a CME. These phenomena may cause some failed predictions of the geoeffectiveness of CMEs. The recent notable event exhibiting such a failure was on 2015 March 15 when a fast CME originated from the west hemisphere. Space Weather Prediction Center (SWPC) of NOAA initially forecasted that the CME would at most cause a very minor geomagnetic disturbance labeled as G1. However, the CME produced the largest geomagnetic storm so far, at G4 level with the provisional Dst value of -223 nT, in the current solar cycle 24 [e.g., Kataoka et al., 2015; Wang et al., 2016]. Such an unexpected phenomenon naturally raises the first question for the forecasting of the geoeffectiveness of a CME, i.e., whether or not a CME will hit the Earth even though we know the source location and initial kinematic properties of the CME. A full understanding of the propagation trajectory, e.g., the deflected propagation, of a CME from the Sun to 1 AU is the key. With a few cases, we show the importance of the deflection effect in the space weather forecasting. An automated CME arrival forecasting system containing a deflected propagation model is presented. References:[1] Kataoka, R., D. Shiota, E. Kilpua, and K. Keika, Pileup accident hypothesis of magnetic storm on 17 March 2015, Geophys. Res. Lett., 42, 5155-5161, 2015.[2] Wang, Yuming, Quanhao Zhang, Jiajia Liu, Chenglong Shen, Fang Shen, Zicai Yang, T. Zic, B. Vrsnak, D. F. Webb, Rui Liu, S. Wang, Jie Zhang, Q. Hu, and B. Zhuang, On the Propagation of a Geoeffective Coronal Mass Ejection during March 15 - 17, 2015, J. Geophys. Res., accepted, doi:10.1002/2016JA022924, 2016.

Elbow mass flow meter

DOEpatents

McFarland, Andrew R.; Rodgers, John C.; Ortiz, Carlos A.; Nelson, David C.

1994-01-01

Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

Spacecraft telecommunications system mass estimates

NASA Technical Reports Server (NTRS)

Yuen, J. H.; Sakamoto, L. L.

1988-01-01

Mass is the most important limiting parameter for present-day planetary spacecraft design, In fact, the entire design can be characterized by mass. The more efficient the design of the spacecraft, the less mass will be required. The communications system is an essential and integral part of planetary spacecraft. A study is presented of the mass attributable to the communications system for spacecraft designs used in recent missions in an attempt to help guide future design considerations and research and development efforts. The basic approach is to examine the spacecraft by subsystem and allocate a portion of each subsystem to telecommunications. Conceptually, this is to divide the spacecraft into two parts, telecommunications and nontelecommunications. In this way, it is clear what the mass attributable to the communications system is. The percentage of mass is calculated using the actual masses of the spacecraft parts, except in the case of CRAF. In that case, estimated masses are used since the spacecraft was not yet built. The results show that the portion of the spacecraft attributable to telecommunications is substantial. The mass fraction for Voyager, Galileo, and CRAF (Mariner Mark 2) is 34, 19, and 18 percent, respectively. The large reduction of telecommunications mass from Voyager to Galileo is mainly due to the use of a deployable antenna instead of the solid antenna on Voyager.

Mass Storage Systems.

ERIC Educational Resources Information Center

Ranade, Sanjay; Schraeder, Jeff

1991-01-01

Presents an overview of the mass storage market and discusses mass storage systems as part of computer networks. Systems for personal computers, workstations, minicomputers, and mainframe computers are described; file servers are explained; system integration issues are raised; and future possibilities are suggested. (LRW)

Microelectromechanical dual-mass resonator structure

DOEpatents

Dyck, Christopher W.; Allen, James J.; Huber, Robert J.

2002-01-01

A dual-mass microelectromechanical (MEM) resonator structure is disclosed in which a first mass is suspended above a substrate and driven to move along a linear or curved path by a parallel-plate electrostatic actuator. A second mass, which is also suspended and coupled to the first mass by a plurality of springs is driven by motion of the first mass. Various modes of operation of the MEM structure are possible, including resonant and antiresonant modes, and a contacting mode. In each mode of operation, the motion induced in the second mass can be in the range of several microns up to more than 50 .mu.m while the first mass has a much smaller displacement on the order of one micron or less. The MEM structure has applications for forming microsensors that detect strain, acceleration, rotation or movement.

Absolute neutrino mass measurements

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

Wolf, Joachim

2011-10-06

The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2{beta}) searches, single {beta}-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy.Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments inmore » Mainz and Troitsk, using tritium as beta emitter. The next generation tritium {beta}-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope ({sup 137}Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R and D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2{beta} decay and single {beta}-decay.« less

A COMPREHENSIVE ANALYSIS OF UNCERTAINTIES AFFECTING THE STELLAR MASS-HALO MASS RELATION FOR 0 < z < 4

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

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

2010-07-01

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

Interaction of Beta-Hydroxy-Beta-Methylbutyrate Free Acid and Adenosine Triphosphate on Muscle Mass, Strength, and Power in Resistance Trained Individuals.

PubMed

Lowery, Ryan P; Joy, Jordan M; Rathmacher, John A; Baier, Shawn M; Fuller, John C; Shelley, Mack C; Jäger, Ralf; Purpura, Martin; Wilson, Stephanie M C; Wilson, Jacob M

2016-07-01

Lowery, RP, Joy, JM, Rathmacher, JA, Baier, SM, Fuller, JC Jr, Shelley, MC II, Jäger, R, Purpura, M, Wilson, SMC, and Wilson, JM. Interaction of beta-hydroxy-beta-methylbutyrate free acid and adenosine triphosphate on muscle mass, strength, and power in resistance trained individuals. J Strength Cond Res 30(7): 1843-1854, 2016-Adenosine-5'-triphosphate (ATP) supplementation helps maintain performance under high fatiguing contractions and with greater fatigue recovery demands also increase. Current evidence suggests that the free acid form of β-hydroxy-β-methylbutyrate (HMB-FA) acts by speeding regenerative capacity of skeletal muscle after high-intensity or prolonged exercise. Therefore, we investigated the effects of 12 weeks of HMB-FA (3 g) and ATP (400 mg) administration on lean body mass (LBM), strength, and power in trained individuals. A 3-phase double-blind, placebo-, and diet-controlled study was conducted. Phases consisted of an 8-week periodized resistance training program (phase 1), followed by a 2-week overreaching cycle (phase 2), and a 2-week taper (phase 3). Lean body mass was increased by a combination of HMB-FA/ATP by 12.7% (p < 0.001). In a similar fashion, strength gains after training were increased in HMB-FA/ATP-supplemented subjects by 23.5% (p < 0.001). Vertical jump and Wingate power were increased in the HMB-FA/ATP-supplemented group compared with the placebo-supplemented group, and the 12-week increases were 21.5 and 23.7%, respectively. During the overreaching cycle, strength and power declined in the placebo group (4.3-5.7%), whereas supplementation with HMB-FA/ATP resulted in continued strength gains (1.3%). In conclusion, HMB-FA and ATP in combination with resistance exercise training enhanced LBM, power, and strength. In addition, HMB-FA plus ATP blunted the typical response to overreaching, resulting in a further increase in strength during that period. It seems that the combination of HMB-FA/ATP could benefit those who

Spatially unresolved SED fitting can underestimate galaxy masses: a solution to the missing mass problem

NASA Astrophysics Data System (ADS)

Sorba, Robert; Sawicki, Marcin

2018-05-01

We perform spatially resolved, pixel-by-pixel Spectral Energy Distribution (SED) fitting on galaxies up to z ˜ 2.5 in the Hubble eXtreme Deep Field (XDF). Comparing stellar mass estimates from spatially resolved and spatially unresolved photometry we find that unresolved masses can be systematically underestimated by factors of up to 5. The ratio of the unresolved to resolved mass measurement depends on the galaxy's specific star formation rate (sSFR): at low sSFRs the bias is small, but above sSFR ˜ 10-9.5 yr-1 the discrepancy increases rapidly such that galaxies with sSFRs ˜ 10-8 yr-1 have unresolved mass estimates of only one-half to one-fifth of the resolved value. This result indicates that stellar masses estimated from spatially unresolved data sets need to be systematically corrected, in some cases by large amounts, and we provide an analytic prescription for applying this correction. We show that correcting stellar mass measurements for this bias changes the normalization and slope of the star-forming main sequence and reduces its intrinsic width; most dramatically, correcting for the mass bias increases the stellar mass density of the Universe at high redshift and can resolve the long-standing discrepancy between the directly measured cosmic SFR density at z ≳ 1 and that inferred from stellar mass densities (`the missing mass problem').

Disk Masses around Solar-mass Stars are Underestimated by CO Observations

NASA Astrophysics Data System (ADS)

Yu, Mo; Evans, Neal J., II; Dodson-Robinson, Sarah E.; Willacy, Karen; Turner, Neal J.

2017-05-01

Gas in protostellar disks provides the raw material for giant planet formation and controls the dynamics of the planetesimal-building dust grains. Accurate gas mass measurements help map the observed properties of planet-forming disks onto the formation environments of known exoplanets. Rare isotopologues of carbon monoxide (CO) have been used as gas mass tracers for disks in the Lupus star-forming region, with an assumed interstellar CO/H2 abundance ratio. Unfortunately, observations of T-Tauri disks show that CO abundance is not interstellar, a finding reproduced by models that show CO abundance decreasing both with distance from the star and as a function of time. Here, we present radiative transfer simulations that assess the accuracy of CO-based disk mass measurements. We find that the combination of CO chemical depletion in the outer disk and optically thick emission from the inner disk leads observers to underestimate gas mass by more than an order of magnitude if they use the standard assumptions of interstellar CO/H2 ratio and optically thin emission. Furthermore, CO abundance changes on million-year timescales, introducing an age/mass degeneracy into observations. To reach a factor of a few accuracy for CO-based disk mass measurements, we suggest that observers and modelers adopt the following strategies: (1) select low-J transitions; (2) observe multiple CO isotopologues and use either intensity ratios or normalized line profiles to diagnose CO chemical depletion; and (3) use spatially resolved observations to measure the CO-abundance distribution.

Miniature Piezoelectric Macro-Mass Balance

NASA Technical Reports Server (NTRS)

Sherrit, Stewart; Trebi-Ollennu, Ashitey; Bonitz, Robert G.; Bar-Cohen, Yoseph

2010-01-01

Mass balances usually use a strain gauge that requires an impedance measurement and is susceptible to noise and thermal drift. A piezoelectric balance can be used to measure mass directly by monitoring the voltage developed across the piezoelectric balance, which is linear with weight or it can be used in resonance to produce a frequency change proportional to the mass change (see figure). The piezoelectric actuator/balance is swept in frequency through its fundamental resonance. If a small mass is added to the balance, the resonance frequency shifts down in proportion to the mass. By monitoring the frequency shift, the mass can be determined. This design allows for two independent measurements of mass. Additionally, more than one sample can be verified because this invention allows for each sample to be transported away from the measuring device upon completion of the measurement, if required. A piezoelectric actuator, or many piezoelectric actuators, was placed between the collection plate of the sampling system and the support structure. As the sample mass is added to the plate, the piezoelectrics are stressed, causing them to produce a voltage that is proportional to the mass and acceleration. In addition, a change in mass delta m produces a change in the resonance frequency with delta f proportional to delta m. In a microgravity environment, the spacecraft could be accelerated to produce a force on the piezoelectric actuator that would produce a voltage proportional to the mass and acceleration. Alternatively, the acceleration could be used to force the mass on the plate, and the inertial effects of the mass on the plate would produce a shift in the resonance frequency with the change in frequency related to the mass change. Three prototypes of the mass balance mechanism were developed. These macro-mass balances each consist of a solid base and an APA 60 Cedrat flextensional piezoelectric actuator supporting a measuring plate. A similar structure with 3 APA

Relationships between HI Gas Mass, Stellar Mass and Star Formation Rate of HICAT+WISE Galaxies

NASA Astrophysics Data System (ADS)

Parkash, Vaishali; Brown, Michael J. I.

2018-01-01

Galaxies grow via a combination of star formation and mergers. In this thesis, I have studied what drives star formation in nearby galaxies. Using archival WISE, Galex, 21-cm data and new IFU observations, I examine the HI content, Hα emission, stellar kinematics, and gas kinematics of three sub-classes of galaxies: spiral galaxies, shell galaxies and HI galaxies with unusually low star formation rates (SFR). In this dissertation talk, I will focus on the scaling relations between atomic (HI) gas, stellar mass and SFR of spiral galaxies. Star formation is fuelled by HI and molecular hydrogen, therefore we expect correlations between HI mass, stellar mass and SFR. However, the measured scaling relationships vary in the prior literature due to sample selection or low completeness. I will discuss new scaling relationships determined using HI Parkes All Sky-Survey Catalogue (HICAT) and the Wide-field Infrared Survey Explorer (WISE). The combination of the local HICAT survey with sensitive WISE mid-infrared imaging improves the stellar masses, SFRs and completeness relative to previous literature. Of the 3,513 HICAT sources, we find 3.4 μm counterparts for 2,824 sources (80%), and provide new WISE matched aperture photometry for these galaxies. For a stellar mass selected sample of z ≤ 0.01 spiral galaxies, we find HI detections for 94% of the galaxies, enabling us to accurately measure HI mass as a function of stellar mass. In contrast to HI-selected galaxy samples, we find that star formation efficiency of spiral galaxies is constant at 10-9.5 yr‑1 with a scatter of 0.5 dex for stellar masses above 109.5 solar masses. We find HI mass increases with stellar mass for spiral galaxies, but the scatter is 1.7 dex for all spiral galaxies and 0.6 dex for galaxies with the T-type 5 to 7. We find an upper limit on HI mass that depends on stellar mass, which is consistent with this limit being dictated by the halo spin parameter.

How to Explain the Non-Zero Mass of Electromagnetic Radiation Consisting of Zero-Mass Photons

ERIC Educational Resources Information Center

Gabovich, Alexander M.; Gabovich, Nadezhda A.

2007-01-01

The mass of electromagnetic radiation in a cavity is considered using the correct relativistic approach based on the concept of a scalar mass not dependent on the particle (system) velocity. It is shown that due to the non-additivity of mass in the special theory of relativity the ensemble of chaotically propagating mass-less photons in the cavity…

In situ mass analysis of particles by surface ionization mass spectrometry

NASA Technical Reports Server (NTRS)

Lassiter, W. S.; Moen, A. L.

1974-01-01

A qualitative study of the application of surface ionization and mass spectrometry to the in situ detection and constituent analysis of atmospheric particles was conducted. The technique consists of mass analysis of ions formed as a result of impingement of a stream of particles on a hot filament where, it is presumed, surface ionization takes place. Laboratory air particles containing K, Ca, and possibly hydrocarbons were detected. Other known particles such as Al2O3, Pb(NO3)2, and Cr2O3 were analyzed by detecting the respective metal atoms making up the particles. In some cases, mass numbers indicative of compounds making up the particles were detected showing surface ionization of particles sometimes leads to chemical analysis as well as to elemental analysis. Individual particles were detected, and it was shown that the technique is sensitive to Al2O3 particles with a mass of a few nanograms.

Constraints from Dust Mass and Mass Accretion Rate Measurements on Angular Momentum Transport in Protoplanetary Disks

NASA Astrophysics Data System (ADS)

Mulders, Gijs D.; Pascucci, Ilaria; Manara, Carlo F.; Testi, Leonardo; Herczeg, Gregory J.; Henning, Thomas; Mohanty, Subhanjoy; Lodato, Giuseppe

2017-09-01

In this paper, we investigate the relation between disk mass and mass accretion rate to constrain the mechanism of angular momentum transport in protoplanetary disks. We find a correlation between dust disk mass and mass accretion rate in Chamaeleon I with a slope that is close to linear, similar to the one recently identified in Lupus. We investigate the effect of stellar mass and find that the intrinsic scatter around the best-fit {M}{dust}-{M}\\star and {\\dot{M}}{acc}-{M}\\star relations is uncorrelated. We simulate synthetic observations of an ensemble of evolving disks using a Monte Carlo approach and find that disks with a constant α viscosity can fit the observed relations between dust mass, mass accretion rate, and stellar mass but overpredict the strength of the correlation between disk mass and mass accretion rate when using standard initial conditions. We find two possible solutions. In the first one, the observed scatter in {M}{dust} and {\\dot{M}}{acc} is not primordial, but arises from additional physical processes or uncertainties in estimating the disk gas mass. Most likely grain growth and radial drift affect the observable dust mass, while variability on large timescales affects the mass accretion rates. In the second scenario, the observed scatter is primordial, but disks have not evolved substantially at the age of Lupus and Chamaeleon I owing to a low viscosity or a large initial disk radius. More accurate estimates of the disk mass and gas disk sizes in a large sample of protoplanetary disks, through either direct observations of the gas or spatially resolved multiwavelength observations of the dust with ALMA, are needed to discriminate between both scenarios or to constrain alternative angular momentum transport mechanisms such as MHD disk winds.

Imaging mass spectrometry statistical analysis.

PubMed

Jones, Emrys A; Deininger, Sören-Oliver; Hogendoorn, Pancras C W; Deelder, André M; McDonnell, Liam A

2012-08-30

Imaging mass spectrometry is increasingly used to identify new candidate biomarkers. This clinical application of imaging mass spectrometry is highly multidisciplinary: expertise in mass spectrometry is necessary to acquire high quality data, histology is required to accurately label the origin of each pixel's mass spectrum, disease biology is necessary to understand the potential meaning of the imaging mass spectrometry results, and statistics to assess the confidence of any findings. Imaging mass spectrometry data analysis is further complicated because of the unique nature of the data (within the mass spectrometry field); several of the assumptions implicit in the analysis of LC-MS/profiling datasets are not applicable to imaging. The very large size of imaging datasets and the reporting of many data analysis routines, combined with inadequate training and accessible reviews, have exacerbated this problem. In this paper we provide an accessible review of the nature of imaging data and the different strategies by which the data may be analyzed. Particular attention is paid to the assumptions of the data analysis routines to ensure that the reader is apprised of their correct usage in imaging mass spectrometry research. Copyright © 2012 Elsevier B.V. All rights reserved.

A Steeper than Linear Disk Mass-Stellar Mass Scaling Relation

NASA Astrophysics Data System (ADS)

Pascucci, Ilaria; SLICK, EOS

2017-01-01

The disk mass is among the most important input parameter of planet formation models as it determines the number and masses of the planets that can form. I will present an ALMA 887 micron survey of the disk population around objects from 2 to 0.03Msun in the nearby 2 Myr-old Chamaeleon I star-forming region. Assuming isothermal and optically thin emission, we convert the 887 micron flux densities into dust disk masses (Mdust) and show that the Mdust-Mstar scaling relation is steeper than linear. By re-analyzing all millimeter data available for nearby regions in a self-consistent way, we find that the 1-3 Myr-old regions of Taurus, Lupus, and Chamaeleon I share the same Mdust-Mstar relation, while the 10 Myr-old Upper Sco association has an even steeper relation. Theoretical models of grain growth, drift, and fragmentation reproduce this trend and suggest that disks are in the fragmentation-limited regime. In this regime millimeter grains will be located closer in around lower-mass stars, a prediction that can be tested with deeper and higher spatial resolution ALMA observations.

MASS SPECTROMETRY

DOEpatents

Nier, A.O.C.

1959-08-25

A voltage switching apparatus is described for use with a mass spectrometer in the concentratron analysis of several components of a gas mixture. The system automatically varies the voltage on the accelerating electrode of the mass spectrometer through a program of voltages which corresponds to the particular gas components under analysis. Automatic operation may be discontinued at any time to permit the operator to manually select any desired predetermined accelerating voltage. Further, the system may be manually adjusted to vary the accelerating voltage over a wide range.

Probing the Jet Turnover Frequency Dependence on Mass and Mass Accretion Rate

NASA Astrophysics Data System (ADS)

Hammerstein, Erica; Gültekin, Kayhan; King, Ashley

2018-01-01

We have examined a sample of 15 sub-Eddington supermassive black holes (SMBHs) in a variety of galaxy classifications to further understand the proposed fundamental plane of black hole activity and scaling relations between black hole masses and their radio and X-ray luminosities. This plane describes black holes from stellar-mass to supermassive. The physics probed by these sub-Eddington systems is thought to be a radiatively inefficient, jet-dominated accretion flow. By studying black holes in this regime, we can learn important information on the disk-jet connection for accreting black holes.A key factor in studying the fundamental plane is the turnover frequency — the frequency at which emission transitions from optically thick at lower frequencies to optically thin at higher frequencies. This turnover point can be measured by observing the source in both radio and X-ray. Our project aims to test the dependence of the turnover frequency on mass and mass accretion rate.Radio observations of the sample were obtained using the Karl G. Jansky Very Large Array (VLA) in the range of 5-40 GHz across four different frequency bands in A configuration to give the highest spatial resolution to focus on the core emission. Our carefully chosen sample of SMBHs with dynamically measured masses consists of two sub-samples: those with approximately constant mass accretion rate (LX/LEdd ~ 10‑7) and those with approximately constant mass (MBH ~ 108 Msun). X-ray data were obtained from archival Chandra observations. To find the turnover frequency, we used Markov Chain Monte Carlo methods to fit two power laws to the radio data and the archival X-ray data. The intersection of the radio and X-ray fits is the turnover frequency.We present the results for both subsamples of SMBHs and their relationship between the turnover frequency and X-ray luminosity, which we take to scale with mass accretion rate, and jet power derived from both radio and X-ray properties.

Surface term effects on mass estimators

NASA Astrophysics Data System (ADS)

Membrado, M.; Pacheco, A. F.

2016-05-01

Context. We propose a way of estimating the mass contained in the volume occupied by a sample of galaxies in a virialized system. Aims: We analyze the influence of surface effects and the contribution of the cosmological constant terms on our mass estimations of galaxy systems. Methods: We propose two equations that contain surface terms to estimate galaxy sample masses. When the surface terms are neglected, these equations provide the so-called virial and projected masses. Both equations lead to a single equation that allows sample masses to be estimated without the need for calculating surface terms. Sample masses for some nearest galaxy groups are estimated and compared with virialized masses determined from turn-around radii and results of a spherical infall model. Results: Surface effects have a considerable effect on the mass estimations of the studied galaxy groups. According to our results, they lead sample masses of some groups to being less than half the virial mass estimations and even less than 10% of projected mass estimations. However, the contributions of cosmological constant terms to mass estimations are smaller than 2% for the majority of the virialized groups studied. Our estimations are in agreement with virialized masses calculated from turn-around radii. Virialized masses for complexes were found to be: (8.9 ± 2.8) × 1011 M⊙ for the Milky Way - M 31; (12.5 ± 2.5) × 1011 M⊙ for M 81 - NGC 2403; (21.5 ± 7.7) × 1011 M⊙. for Cantaurs A - M 83; and (7.9 ± 2.6) × 1011 M⊙. for IC 324 - Maffei. Conclusions: The nearest galaxy groups located inside a sphere of 5 Mpc have been addressed to explore the performance of our mass estimator. We have seen that surface effects make mass estimations of galaxy groups rather smaller than both virial and projected masses. In mass calculations, cosmological constant terms can be neglected; nevertheless, the collapse of cold dark matter leading to virialized structures is strongly affected by the

Greenland Ice Sheet Mass Balance

NASA Technical Reports Server (NTRS)

Reeh, N.

1984-01-01

Mass balance equation for glaciers; areal distribution and ice volumes; estimates of actual mass balance; loss by calving of icebergs; hydrological budget for Greenland; and temporal variations of Greenland mass balance are examined.

Surface mass balance contributions to acceleration of Antarctic ice mass loss during 2003-2013

NASA Astrophysics Data System (ADS)

Seo, Ki-Weon; Wilson, Clark R.; Scambos, Ted; Kim, Baek-Min; Waliser, Duane E.; Tian, Baijun; Kim, Byeong-Hoon; Eom, Jooyoung

2015-05-01

Recent observations from satellite gravimetry (the Gravity Recovery and Climate Experiment (GRACE) mission) suggest an acceleration of ice mass loss from the Antarctic Ice Sheet (AIS). The contribution of surface mass balance changes (due to variable precipitation) is compared with GRACE-derived mass loss acceleration by assessing the estimated contribution of snow mass from meteorological reanalysis data. We find that over much of the continent, the acceleration can be explained by precipitation anomalies. However, on the Antarctic Peninsula and other parts of West Antarctica, mass changes are not explained by precipitation and are likely associated with ice discharge rate increases. The total apparent GRACE acceleration over all of the AIS between 2003 and 2013 is -13.6 ± 7.2 Gt/yr2. Of this total, we find that the surface mass balance component is -8.2 ± 2.0 Gt/yr2. However, the GRACE estimate appears to contain errors arising from the atmospheric pressure fields used to remove air mass effects. The estimated acceleration error from this effect is about 9.8 ± 5.8 Gt/yr2. Correcting for this yields an ice discharge acceleration of -15.1 ± 6.5 Gt/yr2.

Surface Mass Balance Contributions to Acceleration of Antarctic Ice Mass Loss during 2003- 2013

NASA Astrophysics Data System (ADS)

Seo, K. W.; Wilson, C. R.; Scambos, T. A.; Kim, B. M.; Waliser, D. E.; Tian, B.; Kim, B.; Eom, J.

2015-12-01

Recent observations from satellite gravimetry (the GRACE mission) suggest an acceleration of ice mass loss from the Antarctic Ice Sheet (AIS). The contribution of surface mass balance changes (due to variable precipitation) is compared with GRACE-derived mass loss acceleration by assessing the estimated contribution of snow mass from meteorological reanalysis data. We find that over much of the continent, the acceleration can be explained by precipitation anomalies. However, on the Antarctic Peninsula and other parts of West Antarctica mass changes are not explained by precipitation and are likely associated with ice discharge rate increases. The total apparent GRACE acceleration over all of the AIS between 2003 and 2013 is -13.6±7.2 GTon/yr2. Of this total, we find that the surface mass balance component is -8.2±2.0 GTon/yr2. However, the GRACE estimate appears to contain errors arising from the atmospheric pressure fields used to remove air mass effects. The estimated acceleration error from this effect is about 9.8±5.8 GTon/yr2. Correcting for this yields an ice discharge acceleration of -15.1±6.5 GTon/yr2.

The ALFALFA H I mass function: a dichotomy in the low-mass slope and a locally suppressed `knee' mass

NASA Astrophysics Data System (ADS)

Jones, Michael G.; Haynes, Martha P.; Giovanelli, Riccardo; Moorman, Crystal

2018-06-01

We present the most precise measurement of the z = 0 H I mass function (HIMF) to date based on the final catalogue of the ALFALFA (Arecibo Legacy Fast ALFA) blind H I survey of the nearby Universe. The Schechter function fit has a `knee' mass log (M_{*} h2_{70}/M_{⊙}) = 9.94 ± 0.01 ± 0.05, a low-mass slope parameter α = -1.25 ± 0.02 ± 0.1, and a normalization φ _{*} = (4.5 ± 0.2 ± 0.8) × 10^{-3} h3_{70} Mpc^{-3 dex^{-1}}, with both random and systematic uncertainties as quoted. Together these give an estimate of the H I content of the z = 0 Universe as Ω _{H I} = (3.9 ± 0.1 ± 0.6) × 10^{-4} h^{-1}_{70} (corrected for H I self-absorption). Our analysis of the uncertainties indicates that the `knee' mass is a cosmologically fair measurement of the z = 0 value, with its largest uncertainty originating from the absolute flux calibration, but that the low-mass slope is only representative of the local Universe. We also explore large-scale trends in α and M* across the ALFALFA volume. Unlike with the 40 per cent sample, there is now sufficient coverage in both of the survey fields to make an independent determination of the HIMF in each. We find a large discrepancy in the low-mass slope (Δα = 0.14 ± 0.03) between the two regions, and argue that this is likely caused by the presence of a deep void in one field and the Virgo cluster in the other. Furthermore, we find that the value of the `knee' mass within the Local Volume appears to be suppressed by 0.18 ± 0.04 dex compared to the global ALFALFA value, which explains the lower value measured by the shallower H I Parkes All Sky Survey (HIPASS). We discuss possible explanations and interpretations of these results and how they can be expanded on with future surveys.

Quadrupole Ion Mass Spectrometer for Masses of 2 to 50 Da

NASA Technical Reports Server (NTRS)

Helms, William; Griffin, Timothy P.; Ottens, Andrew; Harrison, Willard

2005-01-01

A customized quadrupole ion-trap mass spectrometer (QITMS) has been built to satisfy a need for a compact, rugged instrument for measuring small concentrations of hydrogen, helium, oxygen, and argon in a nitrogen atmosphere. This QITMS can also be used to perform quantitative analyses of other gases within its molecular-mass range, which is 2 to 50 daltons (Da). (More precisely, it can be used to perform quantitative analysis of gases that, when ionized, are characterized by m/Z ratios between 2 and 50, where m is the mass of an ion in daltons and Z is the number of fundamental electric charges on the ion.

DETERMINATION OF ELEMENTAL COMPOSITIONS BY HIGH RESOLUTION MASS SPECTROMETRY WITHOUT MASS CALIBRANTS

EPA Science Inventory

Widely applicable mass calibrants, including perfluorokerosene, are available for gas-phase introduction of analytes ionized by electron impact (EI) prior to analysis using high resolution mass spectrometry. Unfortunately, no all-purpose calibrants are available for recently dev...

Mass-loss Rates from Coronal Mass Ejections: A Predictive Theoretical Model for Solar-type Stars

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

Cranmer, Steven R.

Coronal mass ejections (CMEs) are eruptive events that cause a solar-type star to shed mass and magnetic flux. CMEs tend to occur together with flares, radio storms, and bursts of energetic particles. On the Sun, CME-related mass loss is roughly an order of magnitude less intense than that of the background solar wind. However, on other types of stars, CMEs have been proposed to carry away much more mass and energy than the time-steady wind. Earlier papers have used observed correlations between solar CMEs and flare energies, in combination with stellar flare observations, to estimate stellar CME rates. This papermore » sidesteps flares and attempts to calibrate a more fundamental correlation between surface-averaged magnetic fluxes and CME properties. For the Sun, there exists a power-law relationship between the magnetic filling factor and the CME kinetic energy flux, and it is generalized for use on other stars. An example prediction of the time evolution of wind/CME mass-loss rates for a solar-mass star is given. A key result is that for ages younger than about 1 Gyr (i.e., activity levels only slightly higher than the present-day Sun), the CME mass loss exceeds that of the time-steady wind. At younger ages, CMEs carry 10–100 times more mass than the wind, and such high rates may be powerful enough to dispel circumstellar disks and affect the habitability of nearby planets. The cumulative CME mass lost by the young Sun may have been as much as 1% of a solar mass.« less

Contributions of lean mass and fat mass to bone mineral density: a study in postmenopausal women.

PubMed

Ho-Pham, Lan T; Nguyen, Nguyen D; Lai, Thai Q; Nguyen, Tuan V

2010-03-26

The relative contribution of lean and fat to the determination of bone mineral density (BMD) in postmenopausal women is a contentious issue. The present study was undertaken to test the hypothesis that lean mass is a better determinant of BMD than fat mass. This cross-sectional study involved 210 postmenopausal women of Vietnamese background, aged between 50 and 85 years, who were randomly sampled from various districts in Ho Chi Minh City (Vietnam). Whole body scans, femoral neck, and lumbar spine BMD were measured by DXA (QDR 4500, Hologic Inc., Waltham, MA). Lean mass (LM) and fat mass (FM) were derived from the whole body scan. Furthermore, lean mass index (LMi) and fat mass index (FMi) were calculated as ratio of LM or FM to body height in metre squared (m2). In multiple linear regression analysis, both LM and FM were independent and significant predictors of BMD at the spine and femoral neck. Age, lean mass and fat mass collectively explained 33% variance of lumbar spine and 38% variance of femoral neck BMD. Replacing LM and FM by LMi and LMi did not alter the result. In both analyses, the influence of LM or LMi was greater than FM and FMi. Simulation analysis suggested that a study with 1000 individuals has a 78% chance of finding the significant effects of both LM and FM, and a 22% chance of finding LM alone significant, and zero chance of finding the effect of fat mass alone. These data suggest that both lean mass and fat mass are important determinants of BMD. For a given body size -- measured either by lean mass or height --women with greater fat mass have greater BMD.

Masses of proton-rich T/sub z/<0 nuclei via the isobaric mass equation

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

Pape, A.; Antony, M.S.

Masses of T/sub z/<0 nuclei through the element Sm, corresponding to Aless than or equal to117, have been calculated with the isobaric multiplet mass equation using parameterizations of its constant b and T/sub z/>0 reference masses of Wapstra, Audi, and Hoekstra. copyright 1988 Academic Press, Inc.

Inorganic trace analysis by mass spectrometry

NASA Astrophysics Data System (ADS)

Becker, Johanna Sabine; Dietze, Hans-Joachim

1998-10-01

Mass spectrometric methods for the trace analysis of inorganic materials with their ability to provide a very sensitive multielemental analysis have been established for the determination of trace and ultratrace elements in high-purity materials (metals, semiconductors and insulators), in different technical samples (e.g. alloys, pure chemicals, ceramics, thin films, ion-implanted semiconductors), in environmental samples (waters, soils, biological and medical materials) and geological samples. Whereas such techniques as spark source mass spectrometry (SSMS), laser ionization mass spectrometry (LIMS), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), glow discharge mass spectrometry (GDMS), secondary ion mass spectrometry (SIMS) and inductively coupled plasma mass spectrometry (ICP-MS) have multielemental capability, other methods such as thermal ionization mass spectrometry (TIMS), accelerator mass spectrometry (AMS) and resonance ionization mass spectrometry (RIMS) have been used for sensitive mono- or oligoelemental ultratrace analysis (and precise determination of isotopic ratios) in solid samples. The limits of detection for chemical elements using these mass spectrometric techniques are in the low ng g -1 concentration range. The quantification of the analytical results of mass spectrometric methods is sometimes difficult due to a lack of matrix-fitted multielement standard reference materials (SRMs) for many solid samples. Therefore, owing to the simple quantification procedure of the aqueous solution, inductively coupled plasma mass spectrometry (ICP-MS) is being increasingly used for the characterization of solid samples after sample dissolution. ICP-MS is often combined with special sample introduction equipment (e.g. flow injection, hydride generation, high performance liquid chromatography (HPLC) or electrothermal vaporization) or an off-line matrix separation and enrichment of trace impurities (especially for characterization of

Osteoporosis: Peak Bone Mass in Women

MedlinePlus

... Osteoporosis: Peak Bone Mass in Women Osteoporosis: Peak Bone Mass in Women Bones are the framework for ... that affect peak bone mass. Factors Affecting Peak Bone Mass A variety of genetic and environmental factors ...

Surface mass balance contributions to acceleration of Antarctic ice mass loss during 2003-2013.

PubMed

Seo, Ki-Weon; Wilson, Clark R; Scambos, Ted; Kim, Baek-Min; Waliser, Duane E; Tian, Baijun; Kim, Byeong-Hoon; Eom, Jooyoung

2015-05-01

Recent observations from satellite gravimetry (the Gravity Recovery and Climate Experiment (GRACE) mission) suggest an acceleration of ice mass loss from the Antarctic Ice Sheet (AIS). The contribution of surface mass balance changes (due to variable precipitation) is compared with GRACE-derived mass loss acceleration by assessing the estimated contribution of snow mass from meteorological reanalysis data. We find that over much of the continent, the acceleration can be explained by precipitation anomalies. However, on the Antarctic Peninsula and other parts of West Antarctica, mass changes are not explained by precipitation and are likely associated with ice discharge rate increases. The total apparent GRACE acceleration over all of the AIS between 2003 and 2013 is -13.6 ± 7.2 Gt/yr 2 . Of this total, we find that the surface mass balance component is -8.2 ± 2.0 Gt/yr 2 . However, the GRACE estimate appears to contain errors arising from the atmospheric pressure fields used to remove air mass effects. The estimated acceleration error from this effect is about 9.8 ± 5.8 Gt/yr 2 . Correcting for this yields an ice discharge acceleration of -15.1 ± 6.5 Gt/yr 2 .

The 1986-87 atomic mass predictions

NASA Astrophysics Data System (ADS)

Haustein, P. E.

1987-12-01

A project to perform a comprehensive update of the atomic mass predictions has recently been concluded and will be published shortly in Atomic Data and Nuclear Data Tables. The project evolved from an ongoing comparison between available mass predictions and reports of newly measured masses of isotopes throughout the mass surface. These comparisons have highlighted a variety of features in current mass models which are responsible for predictions that diverge from masses determined experimentally. The need for a comprehensive update of the atomic mass predictions was therefore apparent and the project was organized and began at the last mass conference (AMCO-VII). Project participants included: Pape and Anthony; Dussel, Caurier and Zuker; Möller and Nix; Möller, Myers, Swiatecki and Treiner; Comay, Kelson, and Zidon; Satpathy and Nayak; Tachibana, Uno, Yamada and Yamada; Spanier and Johansson; Jänecke and Masson; and Wapstra, Audi and Hoekstra. An overview of the new atomic mass predictions may be obtained by written request.

Isobar Separation in a Multiple-Reflection Time-of-Flight Mass Spectrometer by Mass-Selective Re-Trapping.

PubMed

Dickel, Timo; Plaß, Wolfgang R; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I; Geissel, Hans; Scheidenberger, Christoph

2017-06-01

A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry. Graphical Abstract ᅟ.

Isobar Separation in a Multiple-Reflection Time-of-Flight Mass Spectrometer by Mass-Selective Re-Trapping

NASA Astrophysics Data System (ADS)

Dickel, Timo; Plaß, Wolfgang R.; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I.; Geissel, Hans; Scheidenberger, Christoph

2017-06-01

A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry. [Figure not available: see fulltext.

First Direct Mass Measurements of Nuclides around Z =100 with a Multireflection Time-of-Flight Mass Spectrograph

NASA Astrophysics Data System (ADS)

Ito, Y.; Schury, P.; Wada, M.; Arai, F.; Haba, H.; Hirayama, Y.; Ishizawa, S.; Kaji, D.; Kimura, S.; Koura, H.; MacCormick, M.; Miyatake, H.; Moon, J. Y.; Morimoto, K.; Morita, K.; Mukai, M.; Murray, I.; Niwase, T.; Okada, K.; Ozawa, A.; Rosenbusch, M.; Takamine, A.; Tanaka, T.; Watanabe, Y. X.; Wollnik, H.; Yamaki, S.

2018-04-01

The masses of 246Es, 251Fm, and the transfermium nuclei Md-252249 and 254No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed N =152 neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. The masses of 246Es and 249,250,252Md were measured for the first time. Using the masses of Md,250249 as anchor points for α decay chains, the masses of heavier nuclei, up to 261Bh and 266Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter δ2 n derived from three isotopic masses was updated with the new masses and corroborates the existence of the deformed N =152 neutron shell closure for Md and Lr.

Silver Coating for High-Mass-Accuracy Imaging Mass Spectrometry of Fingerprints on Nanostructured Silicon.

PubMed

Guinan, Taryn M; Gustafsson, Ove J R; McPhee, Gordon; Kobus, Hilton; Voelcker, Nicolas H

2015-11-17

Nanostructure imaging mass spectrometry (NIMS) using porous silicon (pSi) is a key technique for molecular imaging of exogenous and endogenous low molecular weight compounds from fingerprints. However, high-mass-accuracy NIMS can be difficult to achieve as time-of-flight (ToF) mass analyzers, which dominate the field, cannot sufficiently compensate for shifts in measured m/z values. Here, we show internal recalibration using a thin layer of silver (Ag) sputter-coated onto functionalized pSi substrates. NIMS peaks for several previously reported fingerprint components were selected and mass accuracy was compared to theoretical values. Mass accuracy was improved by more than an order of magnitude in several cases. This straightforward method should form part of the standard guidelines for NIMS studies for spatial characterization of small molecules.

Mass Properties for Space Systems Standards Development

NASA Technical Reports Server (NTRS)

Beech, Geoffrey

2013-01-01

Current Verbiage in S-120 Applies to Dry Mass. Mass Margin is difference between Required Mass and Predicted Mass. Performance Margin is difference between Predicted Performance and Required Performance. Performance estimates and corresponding margin should be based on Predicted Mass (and other inputs). Contractor Mass Margin reserved from Performance Margin. Remaining performance margin allocated according to mass partials. Compliance can be evaluated effectively by comparison of three areas (preferably on a single sheet). Basic and Predicted Mass (including historical trend). Aggregate potential changes (threats and opportunities) which gives Mass Forecast. Mass Maturity by category (Estimated/Calculated/Actual).

The Young L Dwarf 2MASS J11193254-1137466 Is a Planetary-mass Binary

NASA Astrophysics Data System (ADS)

Best, William M. J.; Liu, Michael C.; Dupuy, Trent J.; Magnier, Eugene A.

2017-07-01

We have discovered that the extremely red, low-gravity L7 dwarf 2MASS J11193254-1137466 is a 0.″14 (3.6 au) binary using Keck laser guide star adaptive optics imaging. 2MASS J11193254-1137466 has previously been identified as a likely member of the TW Hydrae Association (TWA). Using our updated photometric distance and proper motion, a kinematic analysis based on the BANYAN II model gives an 82% probability of TWA membership. At TWA’s 10 ± 3 Myr age and using hot-start evolutionary models, 2MASS J11193254-1137466AB is a pair of {3.7}-0.9+1.2 {M}{Jup} brown dwarfs, making it the lowest-mass binary discovered to date. We estimate an orbital period of {90}-50+80 years. One component is marginally brighter in K band but fainter in J band, making this a probable flux-reversal binary, the first discovered with such a young age. We also imaged the spectrally similar TWA L7 dwarf WISEA J114724.10-204021.3 with Keck and found no sign of binarity. Our evolutionary model-derived {T}{eff} estimate for WISEA J114724.10-204021.3 is ≈230 K higher than for 2MASS J11193254-1137466AB, at odds with the spectral similarity of the two objects. This discrepancy suggests that WISEA J114724.10-204021.3 may actually be a tight binary with masses and temperatures very similar to 2MASS J11193254-1137466AB, or further supporting the idea that near-infrared spectra of young ultracool dwarfs are shaped by factors other than temperature and gravity. 2MASS J11193254-1137466AB will be an essential benchmark for testing evolutionary and atmospheric models in the young planetary-mass regime.

MASS SPECTROMETRY IN ENVIRONMENTAL SCIENCES

EPA Science Inventory

This review covers applications of mass spectrometry to the environmental sciences. From the early applications of mass spectrometry to environmental research in the 1960s and 1970s, mass spectrometry has played an important role in aiding our understanding of environmental poll...

Food Mass Reduction Trade Study

NASA Technical Reports Server (NTRS)

Perchonok, Michele H.; Stoklosa, Adam M.

2009-01-01

Future long duration manned space flights beyond low earth orbit will require the food system to remain safe, acceptable, and nutritious while efficiently balancing appropriate vehicle resources such as mass, volume, power, water, and crewtime. Often, this presents a challenge since maintaining the quality of the food system can result in a higher mass and volume. The Orion vehicle is significantly smaller than the Shuttle vehicle and the International Space Station and the mass and volume available for food is limited. Therefore, the food team has been challenged to reduce the mass of the packaged food from 1.82 kg per person per day to 1.14 kg per person per day. Past work has concentrated on how to reduce the mass of the packaging which contributes to about 15% of the total mass of the packaged food system. Designers have also focused on integrating and optimizing the Orion galley equipment as a system to reduce mass. To date, there has not been a significant effort to determine how to reduce the food itself. The objective of this project is to determine how the mass and volume of the packaged food can be reduced while maintaining caloric and hydration requirements. The following tasks are the key elements to this project: (1) Conduct further analysis of the ISS Standard Menu to determine moisture, protein, carbohydrate, and fat levels. (2) Conduct trade studies to determine how to bring the mass of the food system down. Trade studies may include removing the water of the total food system and/or increasing the fat content. (3) Determine the preferred method for delivery of the new food (e.g. bars, or beverages) and the degree of replacement. (4) Determine whether there are commercially available products that meet the requirements. By the end of this study, an estimate of the mass and volume savings will be provided to the Constellation Program. In addition, if new technologies need to be developed to achieve the mass savings, the technologies, timeline, and

Leading isospin-breaking corrections to pion, kaon, and charmed-meson masses with twisted-mass fermions

NASA Astrophysics Data System (ADS)

Giusti, D.; Lubicz, V.; Tarantino, C.; Martinelli, G.; Sanfilippo, F.; Simula, S.; Tantalo, N.; RM123 Collaboration

2017-06-01

We present a lattice computation of the isospin-breaking corrections to pseudoscalar meson masses using the gauge configurations produced by the European Twisted Mass Collaboration with Nf=2 +1 +1 dynamical quarks at three values of the lattice spacing (a ≃0.062 , 0.082, and 0.089 fm) with pion masses in the range Mπ≃210 - 450 MeV . The strange and charm quark masses are tuned at their physical values. We adopt the RM123 method based on the combined expansion of the path integral in powers of the d - and u -quark mass difference (m^d-m^u) and of the electromagnetic coupling αe m. Within the quenched QED approximation, which neglects the effects of the sea-quark charges, and after the extrapolations to the physical pion mass and to the continuum and infinite volume limits, we provide results for the pion, kaon, and (for the first time) charmed-meson mass splittings, for the prescription-dependent parameters ɛπ0, ɛγ(M S ¯ ,2 GeV ) , ɛK0(M S ¯ ,2 GeV ) , related to the violations of the Dashen's theorem, and for the light quark mass difference (m^ d-m^ u)(M S ¯ ,2 GeV ) .

Discovery and Mass Measurements of a Cold, 10-Earth Mass Planet and Its Host Star

NASA Technical Reports Server (NTRS)

Barry, Richard K.; Muraki, Y.; Han, C.; Bennett, D. P.; Gaudi, B. S.

2011-01-01

We present the discovery and mass measurement of the cold, low-mass planet MOA-2009-BLG-266Lb, made with the gravitational microlensing method. This planet has a mass of mp = 10.4 +/- M(Earth) and orbits a star of Mstar = 0.56 +/- 0.09 M(Sun) at a semi-major axis of a = 3.2 + 1.9/-0.5 AU, and an orbital period of 7.6 +7.7/-1.5 yrs. The planet and host star mass measurements are due to the measurement of the microlensing parallax effect. This measurement was primarily due to the orbital motion of the Earth, but the analysis also demonstrates the capability measure micro lensing parallax with the Deep Impact (or EPOXI) spacecraft in a Heliocentric orbit. The planet mass and orbital distance are similar to predictions for the critical core mass needed to accrete a substantial gaseous envelope, and thus may indicate that this planet is a failed gas giant. This and future microlensing detections will test planet formation theory predictions regarding the prevalence and masses of such planets

Rapid and High-Throughput pan-Orthopoxvirus Detection and Identification using PCR and Mass Spectrometry

DTIC Science & Technology

2009-07-01

used in this manuscript. Several of the co- authors are or were Ibis employees. * E -mail: meshoo@ibisbio.com Introduction The orthopoxviruses (family...its Eradication. Geneva: World Health Organization. 4. Henderson DA, Inglesby TV, Bartlett JG, Ascher MS, Eitzen E , et al. (1999) Smallpox as a...of Rio de Janeiro: preliminary report. Mem Inst Oswaldo Cruz 95: 625–627. 15. Trindade GS, da Fonseca FG, Marques JT, Diniz S, Leite JA, et al. (2004

Dynamical mass estimates in M13

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

Leonard, P.J.T.; Richer, H.B.; Fahlman, G.G.

We have used the proper motion data of Cudworth Monet to make mass estimates in the globular cluster M13 by solving the spherical Jeans equation. We find a mass inside a spherical shell centered on the cluster with a radius corresponding to 390 arcsec on the sky of 5.5 or 7.6 {times} 10{sup 5} M{circle dot}, depending on the adopted cluster distance. This large dynamical mass estimate together with the observed fact that the mass function of M13 is rising steeply at the low-mass end suggest that much of the cluster mass may be in the form of low-mass starsmore » and brown dwarfs.« less

Dynamical mass estimates in M13

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

Leonard, P.J.T.; Richer, H.B.; Fahlman, G.G.

We have used the proper motion data of Cudworth Monet to make mass estimates in the globular cluster M13 by solving the spherical Jeans equation. We find a mass inside a spherical shell centered on the cluster with a radius corresponding to 390 arcsec on the sky of 5.5 or 7.6 {times} 10{sup 5} M{circle_dot}, depending on the adopted cluster distance. This large dynamical mass estimate together with the observed fact that the mass function of M13 is rising steeply at the low-mass end suggest that much of the cluster mass may be in the form of low-mass stars andmore » brown dwarfs.« less

Mass spectrometry. [in organic chemistry

NASA Technical Reports Server (NTRS)

Burlingame, A. L.; Shackleton, C. H. L.; Howe, I.; Chizhov, O. S.

1978-01-01

A review of mass spectrometry in organic chemistry is given, dealing with advances in instrumentation and computer techniques, selected topics in gas-phase ion chemistry, and applications in such fields as biomedicine, natural-product studies, and environmental pollution analysis. Innovative techniques and instrumentation are discussed, along with chromatographic-mass spectrometric on-line computer techniques, mass spectral interpretation and management techniques, and such topics in gas-phase ion chemistry as electron-impact ionization and decomposition, photoionization, field ionization and desorption, high-pressure mass spectrometry, ion cyclotron resonance, and isomerization reactions of organic ions. Applications of mass spectrometry are examined with respect to bio-oligomers and their constituents, biomedically important substances, microbiology, environmental organic analysis, and organic geochemistry.

Ion mass spectrometer

NASA Technical Reports Server (NTRS)

Neugebauer, M. (Inventor); Clay, D. R.; Goldstein, B. E.; Goldstein, R.

1984-01-01

An ion mass spectrometer is described which detects and indicates the characteristics of ions received over a wide angle, and which indicates the mass to charge ratio, the energy, and the direction of each detected ion. The spectrometer includes a magnetic analyzer having a sector magnet that passes ions received over a wide angle, and an electrostatic analyzer positioned to receive ions passing through the magnetic analyzer. The electrostatic analyzer includes a two dimensional ion sensor at one wall of the analyzer chamber, that senses not only the lengthwise position of the detected ion to indicate its mass to charge ratio, but also detects the ion position along the width of the chamber to indicate the direction in which the ion was traveling.

Mass Transfer with Chemical Reaction.

ERIC Educational Resources Information Center

DeCoursey, W. J.

1987-01-01

Describes the organization of a graduate course dealing with mass transfer, particularly as it relates to chemical reactions. Discusses the course outline, including mathematics models of mass transfer, enhancement of mass transfer rates by homogeneous chemical reaction, and gas-liquid systems with chemical reaction. (TW)

An Empirical Mass Function Distribution

NASA Astrophysics Data System (ADS)

Murray, S. G.; Robotham, A. S. G.; Power, C.

2018-03-01

The halo mass function, encoding the comoving number density of dark matter halos of a given mass, plays a key role in understanding the formation and evolution of galaxies. As such, it is a key goal of current and future deep optical surveys to constrain the mass function down to mass scales that typically host {L}\\star galaxies. Motivated by the proven accuracy of Press–Schechter-type mass functions, we introduce a related but purely empirical form consistent with standard formulae to better than 4% in the medium-mass regime, {10}10{--}{10}13 {h}-1 {M}ȯ . In particular, our form consists of four parameters, each of which has a simple interpretation, and can be directly related to parameters of the galaxy distribution, such as {L}\\star . Using this form within a hierarchical Bayesian likelihood model, we show how individual mass-measurement errors can be successfully included in a typical analysis, while accounting for Eddington bias. We apply our form to a question of survey design in the context of a semi-realistic data model, illustrating how it can be used to obtain optimal balance between survey depth and angular coverage for constraints on mass function parameters. Open-source Python and R codes to apply our new form are provided at http://mrpy.readthedocs.org and https://cran.r-project.org/web/packages/tggd/index.html respectively.

Mass modeling for bars

NASA Technical Reports Server (NTRS)

Butler, Thomas G.

1987-01-01

Methods of modeling mass for bars are surveyed. A method for extending John Archer's concept of consistent mass beyond just translational inertia effects is included. Recommendations are given for various types of modeling situations.

Mini ion trap mass spectrometer

DOEpatents

Dietrich, Daniel D.; Keville, Robert F.

1995-01-01

An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

Mini ion trap mass spectrometer

DOEpatents

Dietrich, D.D.; Keville, R.F.

1995-09-19

An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

Improved mass resolution and mass accuracy in TOF-SIMS spectra and images using argon gas cluster ion beams.

PubMed

Shon, Hyun Kyong; Yoon, Sohee; Moon, Jeong Hee; Lee, Tae Geol

2016-06-09

The popularity of argon gas cluster ion beams (Ar-GCIB) as primary ion beams in time-of-flight secondary ion mass spectrometry (TOF-SIMS) has increased because the molecular ions of large organic- and biomolecules can be detected with less damage to the sample surfaces. However, Ar-GCIB is limited by poor mass resolution as well as poor mass accuracy. The inferior quality of the mass resolution in a TOF-SIMS spectrum obtained by using Ar-GCIB compared to the one obtained by a bismuth liquid metal cluster ion beam and others makes it difficult to identify unknown peaks because of the mass interference from the neighboring peaks. However, in this study, the authors demonstrate improved mass resolution in TOF-SIMS using Ar-GCIB through the delayed extraction of secondary ions, a method typically used in TOF mass spectrometry to increase mass resolution. As for poor mass accuracy, although mass calibration using internal peaks with low mass such as hydrogen and carbon is a common approach in TOF-SIMS, it is unsuited to the present study because of the disappearance of the low-mass peaks in the delayed extraction mode. To resolve this issue, external mass calibration, another regularly used method in TOF-MS, was adapted to enhance mass accuracy in the spectrum and image generated by TOF-SIMS using Ar-GCIB in the delayed extraction mode. By producing spectra analyses of a peptide mixture and bovine serum albumin protein digested with trypsin, along with image analyses of rat brain samples, the authors demonstrate for the first time the enhancement of mass resolution and mass accuracy for the purpose of analyzing large biomolecules in TOF-SIMS using Ar-GCIB through the use of delayed extraction and external mass calibration.

On p-mode oscillations in stars from 1 solar mass to 2 solar masses

NASA Astrophysics Data System (ADS)

Audard, N.; Provost, J.

1994-06-01

The structure of stars more massive than about 1.2 solar masses is characterized by a convective core. We have studied the evolution with age and mass of acoustic frequencies of high radical order n and low degree l for models of stars of 1, 1.5 and 2 solar masses. Using a polynomial approximation for the frequency, the p-mode spectrum can be characterized by derived global asteroseismic coefficients, i.e. the mean separation nu0 is approximately equal to nun, l - nun - 1, l and the small frequency separation Delta nu0, 2 is approximately equal to nun, l = 0 - nun - 1, l = 2. The diagram (nu0, delta nu0, 2/nu0) plotted along the evolutionary tracks would help to separate the effects of age and mass. We study the sensitivity of these coefficients and other observable quantities, like the radius and luminosity, to stellar parameters in the vicinity of 1 solar mass and 2 solar masses; this sensitivity substantially depends on the stellar mass and must be taken into account for asteroseismic calibration of stellar clusters. Considering finally some rapid variations of the internal structure, we show that the second frequency difference delta2 nu = nu(subn, l) - 2 nun - 1, l + nun - 2, l exponent gamma in the He II ionization zone.

Methods for recalibration of mass spectrometry data

DOEpatents

Tolmachev, Aleksey V [Richland, WA; Smith, Richard D [Richland, WA

2009-03-03

Disclosed are methods for recalibrating mass spectrometry data that provide improvement in both mass accuracy and precision by adjusting for experimental variance in parameters that have a substantial impact on mass measurement accuracy. Optimal coefficients are determined using correlated pairs of mass values compiled by matching sets of measured and putative mass values that minimize overall effective mass error and mass error spread. Coefficients are subsequently used to correct mass values for peaks detected in the measured dataset, providing recalibration thereof. Sub-ppm mass measurement accuracy has been demonstrated on a complex fungal proteome after recalibration, providing improved confidence for peptide identifications.

Vortex mass in a superfluid

NASA Astrophysics Data System (ADS)

Simula, Tapio

2018-02-01

We consider the inertial mass of a vortex in a superfluid. We obtain a vortex mass that is well defined and is determined microscopically and self-consistently by the elementary excitation energy of the kelvon quasiparticle localized within the vortex core. The obtained result for the vortex mass is found to be consistent with experimental observations on superfluid quantum gases and vortex rings in water. We propose a method to measure the inertial rest mass and Berry phase of a vortex in superfluid Bose and Fermi gases.

The mass function and dynamical mass of young star clusters: why their initial crossing-time matters crucially

NASA Astrophysics Data System (ADS)

Parmentier, Geneviève; Baumgardt, Holger

2012-12-01

We highlight the impact of cluster-mass-dependent evolutionary rates upon the evolution of the cluster mass function during violent relaxation, that is, while clusters dynamically respond to the expulsion of their residual star-forming gas. Mass-dependent evolutionary rates arise when the mean volume density of cluster-forming regions is mass-dependent. In that case, even if the initial conditions are such that the cluster mass function at the end of violent relaxation has the same shape as the embedded-cluster mass function (i.e. infant weight-loss is mass-independent), the shape of the cluster mass function does change transiently during violent relaxation. In contrast, for cluster-forming regions of constant mean volume density, the cluster mass function shape is preserved all through violent relaxation since all clusters then evolve at the same mass-independent rate. On the scale of individual clusters, we model the evolution of the ratio of the dynamical mass to luminous mass of a cluster after gas expulsion. Specifically, we map the radial dependence of the time-scale for a star cluster to return to equilibrium. We stress that fields of view a few pc in size only, typical of compact clusters with rapid evolutionary rates, are likely to reveal cluster regions which have returned to equilibrium even if the cluster experienced a major gas expulsion episode a few Myr earlier. We provide models with the aperture and time expressed in units of the initial half-mass radius and initial crossing-time, respectively, so that our results can be applied to clusters with initial densities, sizes, and apertures different from ours.

THE (BLACK HOLE)-BULGE MASS SCALING RELATION AT LOW MASSES

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

Graham, Alister W.; Scott, Nicholas

2015-01-01

Several recent papers have reported on the occurrence of active galactic nuclei (AGNs) containing undermassive black holes relative to a linear scaling relation between black hole mass (M {sub bh}) and host spheroid stellar mass (M {sub sph,} {sub *}). However, dramatic revisions to the M {sub bh}-M {sub sph,} {sub *} and M {sub bh}-L {sub sph} relations, based on samples containing predominantly inactive galaxies, have recently identified a new steeper relation at M {sub bh} ≲ (2-10) × 10{sup 8} M {sub ☉}, roughly corresponding to M {sub sph,} {sub *} ≲ (0.3-1) × 10{sup 11} M {submore » ☉}. We show that this steeper, quadratic-like M {sub bh}-M {sub sph,} {sub *} relation defined by the Sérsic galaxies, i.e., galaxies without partially depleted cores, roughly tracks the apparent offset of the AGN having 10{sup 5} ≲ M {sub bh}/M {sub ☉} ≲ 0.5 × 10{sup 8}. That is, these AGNs are not randomly offset with low black hole masses, but also follow a steeper (nonlinear) relation. As noted by Busch et al., confirmation or rejection of a possible AGN offset from the steeper M {sub bh}-M {sub sph,} {sub *} relation defined by the Sérsic galaxies will benefit from improved stellar mass-to-light ratios for the spheroids hosting these AGNs. Several implications for formation theories are noted. Furthermore, reasons for possible under- and overmassive black holes, the potential existence of intermediate mass black holes (<10{sup 5} M {sub ☉}), and the new steep (black hole)-(nuclear star cluster) relation, M{sub bh}∝M{sub nc}{sup 2.7±0.7}, are also discussed.« less

Discovery and Mass Measurements of a Cold, Sub-Neptune Mass Planet and Its Host Star

NASA Technical Reports Server (NTRS)

Barry, Richard K., Jr.

2011-01-01

The gravitational microlensing exoplanet detection method is uniquely sensitive to cold, low-mass planets which orbit beyond the snow-line, where the most massive planets are thought to form. The early statistical results from microlensing indicate that Neptune-Saturn mass planets located beyond the snow-line are substantially more common than their counterparts in closer orbits that have found by the Doppler radial velocity method. We present the discovery of the planet MOA-2009-BLG-266Lb, which demonstrates that the gravitational microlensing method also has the capability to measure the masses of cold, low-mass planets. The mass measurements of the host star and the planet are made possible by the detection of the microlensing parallax signal due to the orbital motion or the Earth as well as observations from the EPOXI spacecraft in a Heliocentric orbit. The microlensing light curve indicates a planetary host star mass of M(sun) = 0.54 + / - 0.05M(sun) located at a distance of DL= 2.94 _ 0.21 kpc, orbited by a planet of mass mp= 9.8 +/-1.1M(Earth) with a semi-major axis of a = 3.1(+1.9-0.4)MAU.

Biodiesel Mass Transit Demonstration

DOT National Transportation Integrated Search

2010-04-01

The Biodiesel Mass Transit Demonstration report is intended for mass transit decision makers and fleet managers considering biodiesel use. This is the final report for the demonstration project implemented by the National Biodiesel Board under a gran...

Deconstructed transverse mass variables

DOE PAGES

Ismail, Ahmed; Schwienhorst, Reinhard; Virzi, Joseph S.; ...

2015-04-02

Traditional searches for R-parity conserving natural supersymmetry (SUSY) require large transverse mass and missing energy cuts to separate the signal from large backgrounds. SUSY models with compressed spectra inherently produce signal events with small amounts of missing energy that are hard to explore. We use this difficulty to motivate the construction of "deconstructed" transverse mass variables which are designed preserve information on both the norm and direction of the missing momentum. Here, we demonstrate the effectiveness of these variables in searches for the pair production of supersymmetric top-quark partners which subsequently decay into a final state with an isolated lepton,more » jets and missing energy. We show that the use of deconstructed transverse mass variables extends the accessible compressed spectra parameter space beyond the region probed by traditional methods. The parameter space can further be expanded to neutralino masses that are larger than the difference between the stop and top masses. In addition, we also discuss how these variables allow for novel searches of single stop production, in order to directly probe unconstrained stealth stops in the small stop-and neutralino-mass regime. We also demonstrate the utility of these variables for generic gluino and stop searches in all-hadronic final states. Overall, we demonstrate that deconstructed transverse variables are essential to any search wanting to maximize signal separation from the background when the signal has undetected particles in the final state.« less

Antarctic Ice Mass Balance from GRACE

NASA Astrophysics Data System (ADS)

Boening, C.; Firing, Y. L.; Wiese, D. N.; Watkins, M. M.; Schlegel, N.; Larour, E. Y.

2014-12-01

The Antarctic ice mass balance and rates of change of ice mass over the past decade are analyzed based on observations from the Gravity Recovery and Climate Experiment (GRACE) satellites, in the form of JPL RL05M mascon solutions. Surface mass balance (SMB) fluxes from ERA-Interim and other atmospheric reanalyses successfully account for the seasonal GRACE-measured mass variability, and explain 70-80% of the continent-wide mass variance at interannual time scales. Trends in the residual (GRACE mass - SMB accumulation) mass time series in different Antarctic drainage basins are consistent with time-mean ice discharge rates based on radar-derived ice velocities and thicknesses. GRACE also resolves accelerations in regional ice mass change rates, including increasing rates of mass gain in East Antarctica and accelerating ice mass loss in West Antarctica. The observed East Antarctic mass gain is only partially explained by anomalously large SMB events in the second half of the record, potentially implying that ice discharge rates are also decreasing in this region. Most of the increasing mass loss rate in West Antarctica, meanwhile, is explained by decreasing SMB (principally precipitation) over this time period, part of the characteristic decadal variability in regional SMB. The residual acceleration of 2+/-1 Gt/yr, which is concentrated in the Amundsen Sea Embayment (ASE) basins, represents the contribution from increasing ice discharge rates. An Ice Sheet System Model (ISSM) run with constant ocean forcing and stationary grounding lines both underpredicts the largest trends in the ASE and produces negligible acceleration or interannual variability in discharge, highlighting the potential importance of ocean forcing for setting ice discharge rates at interannual to decadal time scales.

Dynamics of Variable Mass Systems

NASA Technical Reports Server (NTRS)

Eke, Fidelis O.

1998-01-01

This report presents the results of an investigation of the effects of mass loss on the attitude behavior of spinning bodies in flight. The principal goal is to determine whether there are circumstances under which the motion of variable mass systems can become unstable in the sense that their transverse angular velocities become unbounded. Obviously, results from a study of this kind would find immediate application in the aerospace field. The first part of this study features a complete and mathematically rigorous derivation of a set of equations that govern both the translational and rotational motions of general variable mass systems. The remainder of the study is then devoted to the application of the equations obtained to a systematic investigation of the effect of various mass loss scenarios on the dynamics of increasingly complex models of variable mass systems. It is found that mass loss can have a major impact on the dynamics of mechanical systems, including a possible change in the systems stability picture. Factors such as nozzle geometry, combustion chamber geometry, propellant's initial shape, size and relative mass, and propellant location can all have important influences on the system's dynamic behavior. The relative importance of these parameters on-system motion are quantified in a way that is useful for design purposes.

Mass properties measurement system dynamics

NASA Technical Reports Server (NTRS)

Doty, Keith L.

1993-01-01

The MPMS mechanism possess two revolute degrees-of-freedom and allows the user to measure the mass, center of gravity, and the inertia tensor of an unknown mass. The dynamics of the Mass Properties Measurement System (MPMS) from the Lagrangian approach to illustrate the dependency of the motion on the unknown parameters.

Top mass from asymptotic safety

NASA Astrophysics Data System (ADS)

Eichhorn, Astrid; Held, Aaron

2018-02-01

We discover that asymptotically safe quantum gravity could predict the top-quark mass. For a broad range of microscopic gravitational couplings, quantum gravity could provide an ultraviolet completion for the Standard Model by triggering asymptotic freedom in the gauge couplings and bottom Yukawa and asymptotic safety in the top-Yukawa and Higgs-quartic coupling. We find that in a part of this range, a difference of the top and bottom mass of approximately 170GeV is generated and the Higgs mass is determined in terms of the top mass. Assuming no new physics below the Planck scale, we construct explicit Renormalization Group trajectories for Standard Model and gravitational couplings which link the transplanckian regime to the electroweak scale and yield a top pole mass of Mt,pole ≈ 171GeV.

Seed germination ecology of feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes].

PubMed

Chauhan, Bhagirath S

2013-01-01

Feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes] is a C4 grass weed that has the ability to grow in both lowland and upland conditions. Experiments were conducted in the laboratory and screenhouse to evaluate the effect of environmental factors on germination, emergence, and growth of this weed species. Germination in the light/dark regime was higher at alternating day/night temperatures of 30/20 °C (98%) than at 35/25 °C (83%) or 25/15 °C (62%). Germination was completely inhibited by darkness. The osmotic potential and sodium chloride concentrations required for 50% inhibition of maximum germination were -0.7 MPa and 76 mM, respectively. The highest seedling emergence (69%) was observed from the seeds sown on the soil surface and no seedlings emerged from seeds buried at depths of 0.5 cm or more. The use of residue as mulches significantly reduced the emergence and biomass of feather lovegrass seedlings. A residue amount of 0.5 t ha(-1) was needed to suppress 50% of the maximum seedlings. Because germination was strongly stimulated by light and seedling emergence was the highest for the seeds sown on the soil surface, feather lovegrass is likely to become a problematic weed in zero-till systems. The knowledge gained from this study could help in developing effective and sustainable weed management strategies.

Point mass deflectors in gravitational lenses

NASA Technical Reports Server (NTRS)

Dolan, Joseph F.

1988-01-01

The observed properties of the six systems generally accepted as gravitational lenses are compared with the properties predicted for the images of point-mass and distributed mass deflectors. Taken as a statistical distribution, the characteristics of the six known systems strongly suggest the existence of a super-massive black hole as the effective deflecting mass in one or more of these systems. If the deflecting mass in a gravitational lens is a black hole, the distance to the deflecting mass can be determined directly from the difference in light travel time along the separate image paths. (No direct solution for the distance to the deflecting mass exists when the deflecting mass is a galaxy or a cluster of galaxies). Geometric parallaxes of objects at 1000 Mpc distance are of obvious importance in a wide variety of cosmological studies.

Proteomic analysis of JAZ interacting proteins under methyl jasmonate treatment in finger millet.

PubMed

Sen, Saswati; Kundu, Sangeeta; Dutta, Samir Kr

2016-11-01

Jasmonic acid (JA) signaling pathway in plants is activated against various developmental processes as well as biotic and abiotic stresses. The Jasmonate ZIM-domain (JAZ) protein family, the key regulator of plant JA signaling pathway, also participates in phytohormone crosstalk. This is the first study revealing the in vivo interactions of finger millet (Eleusine coracana (L.) Gaertn.) JAZ protein (EcJAZ) under methyl jasmonate (MJ) treatment. The aim of the study was to explore not only the JA signaling pathway but also the phytohormone signaling crosstalk of finger millet, a highly important future crop. From the MJ-treated finger millet seedlings, the EcJAZ interacting proteins were purified by affinity chromatography with the EcJAZ-matrix. Twenty-one proteins of varying functionalities were successfully identified by MALDI-TOF-TOF Mass spectrometry. Apart from the previously identified JAZ binding proteins, most prominently, EcJAZ was found to interact with transcription factors like NAC, GATA and also with Cold responsive protein (COR), etc. that might have extended the range of functionalities of JAZ proteins. Moreover, to evaluate the interactions of EcJAZ in the JA-co-receptor complex, we generated ten in-silico models containing the EcJAZ degron and the COI1-SKP1 of five monocot cereals viz., rice, wheat, maize, Sorghum and Setaria with JA-Ile or coronatine. Our results indicated that the EcJAZ protein of finger millet could act as the signaling hub for the JA and other phytohormone signaling pathways, in response to a diverse set of stressors and developmental cues to provide survival fitness to the plant. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The JaCVAM international validation study on the in vivo comet assay: Selection of test chemicals.

PubMed

Morita, Takeshi; Uno, Yoshifumi; Honma, Masamitsu; Kojima, Hajime; Hayashi, Makoto; Tice, Raymond R; Corvi, Raffaella; Schechtman, Leonard

2015-07-01

The Japanese Center for the Validation of Alternative Methods (JaCVAM) sponsored an international prevalidation and validation study of the in vivo rat alkaline pH comet assay. The main objective of the study was to assess the sensitivity and specificity of the assay for correctly identifying genotoxic carcinogens, as compared with the traditional rat liver unscheduled DNA synthesis assay. Based on existing carcinogenicity and genotoxicity data and chemical class information, 90 chemicals were identified as primary candidates for use in the validation study. From these 90 chemicals, 46 secondary candidates and then 40 final chemicals were selected based on a sufficiency of carcinogenic and genotoxic data, differences in chemical class or genotoxic or carcinogenic mode of action (MOA), availability, price, and ease of handling. These 40 chemicals included 19 genotoxic carcinogens, 6 genotoxic non-carcinogens, 7 non-genotoxic carcinogens and 8 non-genotoxic non-carcinogens. "Genotoxicity" was defined as positive in the Ames mutagenicity test or in one of the standard in vivo genotoxicity tests (primarily the erythrocyte micronucleus assay). These chemicals covered various chemicals classes, MOAs, and genotoxicity profiles and were considered to be suitable for the purpose of the validation study. General principles of chemical selection for validation studies are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

Linear electric field mass spectrometry

DOEpatents

McComas, David J.; Nordholt, Jane E.

1992-01-01

A mass spectrometer and methods for mass spectrometry. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field.

Extratropical Stratosphere-Troposphere Mass Exchange

NASA Technical Reports Server (NTRS)

Schoeberl, Mark R.

2004-01-01

Understanding the exchange of gases between the stratosphere and the troposphere is important for determining how pollutants enter the stratosphere and how they leave. This study does a global analysis of that the exchange of mass between the stratosphere and the troposphere. While the exchange of mass is not the same as the exchange of constituents, you can t get the constituent exchange right if you have the mass exchange wrong. Thus this kind of calculation is an important test for models which also compute trace gas transport. In this study I computed the mass exchange for two assimilated data sets and a GCM. The models all agree that amount of mass descending from the stratosphere to the troposphere in the Northern Hemisphere extra tropics is approx. 10(exp 10) kg/s averaged over a year. The value for the Southern Hemisphere by about a factor of two. ( 10(exp 10) kg of air is the amount of air in 100 km x 100 km area with a depth of 100 m - roughly the size of the D.C. metro area to a depth of 300 feet.) Most people have the idea that most of the mass enters the stratosphere through the tropics. But this study shows that almost 5 times more mass enters the stratosphere through the extra-tropics. This mass, however, is quickly recycled out again. Thus the lower most stratosphere is a mixture of upper stratospheric air and tropospheric air. This is an important result for understanding the chemistry of the lower stratosphere.

Lumped mass model of a 1D metastructure for vibration suppression with no additional mass

NASA Astrophysics Data System (ADS)

Reichl, Katherine K.; Inman, Daniel J.

2017-09-01

The article examines the effectiveness of metastructures for vibration suppression from a weight standpoint. Metastructures, a metamaterial inspired concept, are structures with distributed vibration absorbers. In automotive and aerospace industries, it is critical to have low levels of vibrations while also using lightweight materials. Previous work has shown that metastructures are effective at mitigating vibrations, but do not consider the effects of mass. This work takes mass into consideration by comparing a structure with vibration absorbers to a structure of equal mass with no absorbers. These structures are modeled as one-dimensional lumped mass models, chosen for simplicity. Results compare both the steady-state and the transient responses. As a quantitative performance measure, the H2 norm, which is related to the area under the frequency response function, is calculated and compared for both the metastructure and the baseline structure. These results show that it is possible to obtain a favorable vibration response without adding additional mass to the structure. Additionally, the performance measure is utilized to optimize the geometry of the structure, determine the optimal ratio of mass in the absorber to mass of the host structure, and determine the frequencies of the absorbers. The dynamic response of this model is verified using a finite element analysis.

Mass-Selective Chiral Analysis

NASA Astrophysics Data System (ADS)

Boesl, Ulrich; Kartouzian, Aras

2016-06-01

Three ways of realizing mass-selective chiral analysis are reviewed. The first is based on the formation of diastereomers that are of homo- and hetero- type with respect to the enantiomers of involved chiral molecules. This way is quite well-established with numerous applications. The other two ways are more recent developments, both based on circular dichroism (CD). In one, conventional or nonlinear electronic CD is linked to mass spectrometry (MS) by resonance-enhanced multiphoton ionization. The other is based on CD in the angular distribution of photoelectrons, which is measured in combination with MS via photoion photoelectron coincidence. Among the many important applications of mass-selective chiral analysis, this review focuses on its use as an analytical tool for the development of heterogeneous enantioselective chemical catalysis. There exist other approaches to combine chiral analysis and mass-selective detection, such as chiral chromatography MS, which are not discussed here.

Mass loss and stellar superwinds

NASA Astrophysics Data System (ADS)

Vink, Jorick S.

2017-09-01

Mass loss bridges the gap between massive stars and supernovae (SNe) in two major ways: (i) theoretically, it is the amount of mass lost that determines the mass of the star prior to explosion and (ii) observations of the circumstellar material around SNe may teach us the type of progenitor that made the SN. Here, I present the latest models and observations of mass loss from massive stars, both for canonical massive O stars, as well as very massive stars that show Wolf-Rayet type features. This article is part of the themed issue 'Bridging the gap: from massive stars to supernovae'.

Pre-menarcheal physical activity predicts post-menarcheal lean mass and core strength, but not fat mass

PubMed Central

Day, M.A.; Dowthwaite, J.N.; Rosenbaum, P.F.; Roedel, G.G.; Brocker, A.A.; Scerpella, T.A.

2015-01-01

Objectives: Youth exercise is associated with improved body composition, but details regarding timing and persistence are limited. We examined pre- and circum-menarcheal organized physical activity exposure (PA) as a factor in development of early post-menarcheal lean mass, fat mass and muscle strength. Methods: Participants in a longitudinal study of musculoskeletal growth using dual energy X-ray absorptiometry (DXA) were included based on: 1) Whole body DXA scans: 0.5-1.5 years pre-menarche, 0.5-1.5 years post-menarche; 2) PA records for ≥6 months preceding the first DXA (PREPA) and for the inter-DXA interval (CIRCUMPA). Dominant arm grip strength and sit-ups tests coincided with DXA scans; PA, height and maturity were recorded semi-annually. Regressions correlated PA with lean mass/fat mass/strength, accounting for maturity, body size, and baseline values. Results Seventy girls [baseline: 11.8 yrs (sd 1.0), follow-up: 13.9 years (sd 1.0)] demonstrated circum-menarcheal gains of 25-29% for lean and fat mass and 33% for grip strength. PREPA correlated with pre- and post-menarcheal lean mass, sit-ups and pre-menarcheal fat mass (p<0.05), but not grip strength. CIRCUMPA correlated with only post-menarcheal sub-head lean mass (p=0.03). Conclusions: Lean mass and core strength at 1-year post-menarche were more strongly predicted by pre-menarcheal organized PA than by recent circum-menarcheal PA. PMID:26636280

On the scatter in the relation between stellar mass and halo mass: random or halo formation time dependent?

NASA Astrophysics Data System (ADS)

Wang, Lan; De Lucia, Gabriella; Weinmann, Simone M.

2013-05-01

The empirical traditional halo occupation distribution (HOD) model of Wang et al. fits, by construction, both the stellar mass function and correlation function of galaxies in the local Universe. In contrast, the semi-analytical models of De Lucia & Blazoit (hereafter DLB07) and Guo et al. (hereafter Guo11), built on the same dark matter halo merger trees than the empirical model, still have difficulties in reproducing these observational data simultaneously. We compare the relations between the stellar mass of galaxies and their host halo mass in the three models, and find that they are different. When the relations are rescaled to have the same median values and the same scatter as in Wang et al., the rescaled DLB07 model can fit both the measured galaxy stellar mass function and the correlation function measured in different galaxy stellar mass bins. In contrast, the rescaled Guo11 model still overpredicts the clustering of low-mass galaxies. This indicates that the detail of how galaxies populate the scatter in the stellar mass-halo mass relation does play an important role in determining the correlation functions of galaxies. While the stellar mass of galaxies in the Wang et al. model depends only on halo mass and is randomly distributed within the scatter, galaxy stellar mass depends also on the halo formation time in semi-analytical models. At fixed value of infall mass, galaxies that lie above the median stellar mass-halo mass relation reside in haloes that formed earlier, while galaxies that lie below the median relation reside in haloes that formed later. This effect is much stronger in Guo11 than in DLB07, which explains the overclustering of low mass galaxies in Guo11. Assembly bias in Guo11 model might be overly strong. Nevertheless, in case that a significant assembly bias indeed exists in the real Universe, one needs to use caution when applying current HOD and abundance matching models that employ the assumption of random scatter in the relation

Accuracy of Body Mass Index Versus Lean Mass Index for Prediction of Sarcopenia in Older Women.

PubMed

Benton, M J; Silva-Smith, A L

2018-01-01

We compared accuracy of body mass index (BMI) versus lean mass index (LMI) to predict sarcopenia in 58 community-dwelling women (74.1±0.9 years). Lean mass was measured with multi-frequency bioelectrical impedance analysis, and strength was measured with Arm Curl test, Chair Stand test, and handgrip dynamometry. Sarcopenia was defined as low LMI. When categorized by BMI, normal women had less absolute lean mass (37.6±1.0 vs. 42.6±0.9 kg; P<0.001) and less relative lean mass (14.1±0.2 vs. 16.1±0.2 kg/m2; P<0.001) compared to overweight/obese women, but no differences in strength. When categorized by LMI, normal women had more absolute lean mass (44.0±0.7 vs. 35.7±0.7 kg; P<0.001), more relative lean mass (16.2±0.2 vs. 13.8±0.2 kg/m2; P<0.001), and greater upper body strength (16.7±0.9 vs. 14.2±0.6 arm curls; P<0.05) compared to women with low LMI. BMI failed to accurately predict low values of lean mass and strength. For clinical assessment, calculation of LMI rather than BMI is appropriate.

Small Business Innovations (Mass Microbalance)

NASA Technical Reports Server (NTRS)

1991-01-01

Femtometrics of Costa Mesa, CA, developed the Model 200-1 SAW Mass Microbalance under a NASA Small Business Innovation Research (SBIR) contract with Langley Research Center. The product is described as "the next generation of aerosol mass microbalance technology," because a new type of sensor, the Surface Acoustic Wave (SAW) piezoelectric crystal, offers mass resolution two orders of magnitude greater than the Quartz Crystal Microbalance cascade impactor (QCM) (used at Langley since 1979 for collection and measurement of aerosol particles in the upper atmosphere). The Model 200-1 SAW Mass Microbalance, which provides a 400-fold increase in mass sensitivity per unit area over the QCM, can be used for real-time particle monitoring in clean rooms, measuring chemical vapors in very low concentrations, measuring target chemicals in the stratosphere and in industry as a toxic vapor monitor.

RESOLVE and ECO: The Halo Mass-dependent Shape of Galaxy Stellar and Baryonic Mass Functions

NASA Astrophysics Data System (ADS)

Eckert, Kathleen D.; Kannappan, Sheila J.; Stark, David V.; Moffett, Amanda J.; Berlind, Andreas A.; Norris, Mark A.

2016-06-01

In this work, we present galaxy stellar and baryonic (stars plus cold gas) mass functions (SMF and BMF) and their halo mass dependence for two volume-limited data sets. The first, RESOLVE-B, coincides with the Stripe 82 footprint and is extremely complete down to baryonic mass M bary ˜ 109.1 M ⊙, probing the gas-rich dwarf regime below M bary ˜ 1010 M ⊙. The second, ECO, covers a ˜40× larger volume (containing RESOLVE-A) and is complete to M bary ˜ 109.4 M ⊙. To construct the SMF and BMF we implement a new “cross-bin sampling” technique with Monte Carlo sampling from the full likelihood distributions of stellar or baryonic mass. Our SMFs exhibit the “plateau” feature starting below M star ˜ 1010 M ⊙ that has been described in prior work. However, the BMF fills in this feature and rises as a straight power law below ˜1010 M ⊙, as gas-dominated galaxies become the majority of the population. Nonetheless, the low-mass slope of the BMF is not as steep as that of the theoretical dark matter halo MF. Moreover, we assign group halo masses by abundance matching, finding that the SMF and BMF, separated into four physically motivated halo mass regimes, reveal complex structure underlying the simple shape of the overall MFs. In particular, the satellite MFs are depressed below the central galaxy MF “humps” in groups with mass <1013.5 M ⊙ yet rise steeply in clusters. Our results suggest that satellite destruction and stripping are active from the point of nascent group formation. We show that the key role of groups in shaping MFs enables reconstruction of a given survey’s SMF or BMF based on its group halo mass distribution.

Mass Spectrometers in Space!

NASA Technical Reports Server (NTRS)

Brinckerhoff, William B.

2012-01-01

Exploration of our solar system over several decades has benefitted greatly from the sensitive chemical analyses offered by spaceflight mass spectrometers. When dealing with an unknown environment, the broadband detection capabilities of mass analyzers have proven extremely valuable in determining the composition and thereby the basic nature of space environments, including the outer reaches of Earth s atmosphere, interplanetary space, the Moon, and the planets and their satellites. Numerous mass analyzer types, including quadrupole, monopole, sector, ion trap, and time-of-flight have been incorporated in flight instruments and delivered robotically to a variety of planetary environments. All such instruments went through a rigorous process of application-specific development, often including significant miniaturization, testing, and qualification for the space environment. Upcoming missions to Mars and opportunities for missions to Venus, Europa, Saturn, Titan, asteroids, and comets provide new challenges for flight mass spectrometers that push to state of the art in fundamental analytical technique. The Sample Analysis at Mars (SAM) investigation on the recently-launch Mars Science Laboratory (MSL) rover mission incorporates a quadrupole analyzer to support direct evolved gas as well as gas chromatograph-based analysis of martian rocks and atmosphere, seeking signs of a past or present habitable environment. A next-generation linear ion trap mass spectrometer, using both electron impact and laser ionization, is being incorporated into the Mars Organic Molecule Analyzer (MOMA) instrument, which will be flown to Mars in 2018. These and other mass spectrometers and mission concepts at various stages of development will be described.

New mass anchor points for neutron-deficient heavy nuclei from direct mass measurements of radium and actinium isotopes

NASA Astrophysics Data System (ADS)

Rosenbusch, M.; Ito, Y.; Schury, P.; Wada, M.; Kaji, D.; Morimoto, K.; Haba, H.; Kimura, S.; Koura, H.; MacCormick, M.; Miyatake, H.; Moon, J. Y.; Morita, K.; Murray, I.; Niwase, T.; Ozawa, A.; Reponen, M.; Takamine, A.; Tanaka, T.; Wollnik, H.

2018-06-01

The masses of the exotic isotopes Ac-214210 and Ra-214210 have been measured with a multireflection time-of-flight mass spectrograph. These isotopes were obtained in flight as fusion-evaporation products behind the gas-filled recoil ion separator GARIS-II at RIKEN. The new direct mass measurements serve as an independent and direct benchmark for existing α -γ spectroscopy data in this mass region. Further, new mass anchor points are set for U and Np nuclei close to the N =126 shell closure for a future benchmark of the Z =92 subshell for neutron-deficient heavy isotopes. Our mass results are in general in good agreement with the previously indirectly determined mass values. Together with the measurement data, reasons for possible mass ambiguities from decay-data links between ground states are discussed.

Determining Mass and Persistence of a Reactive Brominated-Solvent DNAPL Source Using Mass Depletion-Mass Flux Reduction Relationships During Pumping

NASA Astrophysics Data System (ADS)

Johnston, C. D.; Davis, G. B.; Bastow, T.; Annable, M. D.; Trefry, M. G.; Furness, A.; Geste, Y.; Woodbury, R.; Rhodes, S.

2011-12-01

Measures of the source mass and depletion characteristics of recalcitrant dense non-aqueous phase liquid (DNAPL) contaminants are critical elements for assessing performance of remediation efforts. This is in addition to understanding the relationships between source mass depletion and changes to dissolved contaminant concentration and mass flux in groundwater. Here we present results of applying analytical source-depletion concepts to pumping from within the DNAPL source zone of a 10-m thick heterogeneous layered aquifer to estimate the original source mass and characterise the time trajectory of source depletion and mass flux in groundwater. The multi-component, reactive DNAPL source consisted of the brominated solvent tetrabromoethane (TBA) and its transformation products (mostly tribromoethene - TriBE). Coring and multi-level groundwater sampling indicated the DNAPL to be mainly in lower-permeability layers, suggesting the source had already undergone appreciable depletion. Four simplified source dissolution models (exponential, power function, error function and rational mass) were able to describe the concentration history of the total molar concentration of brominated organics in extracted groundwater during 285 days of pumping. Approximately 152 kg of brominated compounds were extracted. The lack of significant kinetic mass transfer limitations in pumped concentrations was notable. This was despite the heterogeneous layering in the aquifer and distribution of DNAPL. There was little to choose between the model fits to pumped concentration time series. The variance of groundwater velocities in the aquifer determined during a partitioning inter-well tracer test (PITT) were used to parameterise the models. However, the models were found to be relatively insensitive to this parameter. All models indicated an initial source mass around 250 kg which compared favourably to an estimate of 220 kg derived from the PITT. The extrapolated concentrations from the

A Hartree-Fock-Bogoliubov mass formula

NASA Astrophysics Data System (ADS)

Samyn, M.; Goriely, S.; Heenen, P.-H.; Pearson, J. M.; Tondeur, F.

2002-03-01

In order to have more reliable predictions of nuclear masses at the neutron drip line, we here go beyond the recent mass formula HFBCS-1 and present a new mass formula, HFB-1, based on the Hartree-Fock-Bogoliubov method. As with the HFBCS-1 mass formula, we use a 10-parameter Skyrme force along with a 4-parameter δ-function pairing force and a 2-parameter phenomenological Wigner term. However, with the original HFBCS-1 Skyrme force (MSk7), the rms error becomes unacceptably large and a new force fit is required. With the isoscalar and isovector effective masses constrained to be equal, the remaining 15 degrees of freedom are fitted to the masses of all the 1754 measured nuclei with A⩾16, | N- Z|>2 given in the 1995 Audi-Wapstra compilation. The rms error with respect to the masses of all the 1888 measured nuclei with Z, N⩾8 is 0.764 MeV. A complete mass table, HFB-1 (available on the Web), has been constructed, giving all nuclei lying between the two drip lines over the range Z, N⩾8 and Z⩽120. A comparison between HFB-1 and HFBCS-1 mass tables shows that the HFBCS model is a very good approximation of the HFB theory, in particular for masses, the extrapolated masses never differing by more than 2 MeV below Z⩽110. We also find that the behaviour of shell gaps far away from the region of beta stability does not depend on whether the HFBCS or HFB methods are used, in particular, no quenching of astrophysical interest arises from replacing the BCS method by the Bogoliubov method.

The double well mass filter

DOE PAGES

Gueroult, Renaud; Rax, Jean -Marcel; Fisch, Nathaniel J.

2014-02-03

Various mass filter concepts based on rotating plasmas have been suggested with the specific purpose of nuclear waste remediation. We report on a new rotating mass filter combining radial separation with axial extraction. Lastly, the radial separation of the masses is the result of a “double-well” in effective radial potential in rotating plasma with a sheared rotation profile.

Linear electric field mass spectrometry

DOEpatents

McComas, D.J.; Nordholt, J.E.

1992-12-01

A mass spectrometer and methods for mass spectrometry are described. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field. 8 figs.

High-accuracy mass spectrometry for fundamental studies.

PubMed

Kluge, H-Jürgen

2010-01-01

Mass spectrometry for fundamental studies in metrology and atomic, nuclear and particle physics requires extreme sensitivity and efficiency as well as ultimate resolving power and accuracy. An overview will be given on the global status of high-accuracy mass spectrometry for fundamental physics and metrology. Three quite different examples of modern mass spectrometric experiments in physics are presented: (i) the retardation spectrometer KATRIN at the Forschungszentrum Karlsruhe, employing electrostatic filtering in combination with magnetic-adiabatic collimation-the biggest mass spectrometer for determining the smallest mass, i.e. the mass of the electron anti-neutrino, (ii) the Experimental Cooler-Storage Ring at GSI-a mass spectrometer of medium size, relative to other accelerators, for determining medium-heavy masses and (iii) the Penning trap facility, SHIPTRAP, at GSI-the smallest mass spectrometer for determining the heaviest masses, those of super-heavy elements. Finally, a short view into the future will address the GSI project HITRAP at GSI for fundamental studies with highly-charged ions.

Plant growth promotion properties of bacterial strains isolated from the rhizosphere of the Jerusalem artichoke (Helianthus tuberosus L.) adapted to saline-alkaline soils and their effect on wheat growth.

PubMed

Liu, Xiaolin; Li, Xiangyue; Li, Yan; Li, Runzhi; Xie, Zhihong

2017-03-01

The Jerusalem artichoke (JA; Helianthus tuberosus), known to be tolerant to saline-alkaline soil conditions, has been cultivated for many years in the Yellow River delta, Shandong Province coastal zone, in China. The aim of our study was to isolate nitrogen-fixing bacteria colonizing the rhizosphere of JA and to characterize other plant growth promotion properties. The ultimate goal was to identify isolates that could be used as inoculants benefiting an economic crop, in particular for improving wheat growth production in the Yellow River delta. Bacterial strains were isolated from the rhizosphere soil of JA on the basis of growth on nitrogen-free Ashby medium. Identification and phylogenetic analysis was performed after nucleotide sequencing of 16S rRNA gene. Plant-growth-promoting traits, such as nitrogen fixation activity, phosphate solubilization activity, indole-3-acetic acid production, were determined using conventional methods. Eleven strains were isolated and 6 of them were further examined for their level of salt tolerance and their effect on plant growth promotion. Inoculation of Enterobacter sp. strain N10 on JA and wheat led to significant increases in both root and shoot dry mass and shoot height. Enterobacter sp. strain N10 appeared to be the best plant-growth-promoting rhizobacteria to increase wheat productivity in future field applications.

A mass transfer origin for blue stragglers in NGC 188 as revealed by half-solar-mass companions.

PubMed

Geller, Aaron M; Mathieu, Robert D

2011-10-19

In open star clusters, where all members formed at about the same time, blue straggler stars are typically observed to be brighter and bluer than hydrogen-burning main-sequence stars, and therefore should already have evolved into giant stars and stellar remnants. Correlations between blue straggler frequency and cluster binary star fraction, core mass and radial position suggest that mass transfer or mergers in binary stars dominates the production of blue stragglers in open clusters. Analytic models, detailed observations and sophisticated N-body simulations, however, argue in favour of stellar collisions. Here we report that the blue stragglers in long-period binaries in the old (7 × 10(9)-year) open cluster NGC 188 have companions with masses of about half a solar mass, with a surprisingly narrow mass distribution. This conclusively rules out a collisional origin, as the collision hypothesis predicts a companion mass distribution with significantly higher masses. Mergers in hierarchical triple stars are marginally permitted by the data, but the observations do not favour this hypothesis. The data are highly consistent with a mass transfer origin for the long-period blue straggler binaries in NGC 188, in which the companions would be white dwarfs of about half a solar mass.

ACTOMP - AUTOCAD TO MASS PROPERTIES

NASA Technical Reports Server (NTRS)

Jones, A.

1994-01-01

AutoCAD to Mass Properties was developed to facilitate quick mass properties calculations of structures having many simple elements in a complex configuration such as trusses or metal sheet containers. Calculating the mass properties of structures of this type can be a tedious and repetitive process, but ACTOMP helps automate the calculations. The structure can be modelled in AutoCAD or a compatible CAD system in a matter of minutes using the 3-Dimensional elements. This model provides all the geometric data necessary to make a mass properties calculation of the structure. ACTOMP reads the geometric data of a drawing from the Drawing Interchange File (DXF) used in AutoCAD. The geometric entities recognized by ACTOMP include POINTs, 3DLINEs, and 3DFACEs. ACTOMP requests mass, linear density, or area density of the elements for each layer, sums all the elements and calculates the total mass, center of mass (CM) and the mass moments of inertia (MOI). AutoCAD utilizes layers to define separate drawing planes. ACTOMP uses layers to differentiate between multiple types of similar elements. For example if a structure is made of various types of beams, modeled as 3DLINEs, each with a different linear density, the beams can be grouped by linear density and each group placed on a separate layer. The program will request the linear density of 3DLINEs for each new layer it finds as it processes the drawing information. The same is true with POINTs and 3DFACEs. By using layers this way a very complex model can be created. POINTs are used for point masses such as bolts, small machine parts, or small electronic boxes. 3DLINEs are used for beams, bars, rods, cables, and other similarly slender elements. 3DFACEs are used for planar elements. 3DFACEs may be created as 3 or 4 Point faces. Some examples of elements that might be modelled using 3DFACEs are plates, sheet metal, fabric, boxes, large diameter hollow cylinders and evenly distributed masses. ACTOMP was written in Microsoft

Mass Determination of Entire Amyloid Fibrils by Using Mass Spectrometry.

PubMed

Doussineau, Tristan; Mathevon, Carole; Altamura, Lucie; Vendrely, Charlotte; Dugourd, Philippe; Forge, Vincent; Antoine, Rodolphe

2016-02-12

Amyloid fibrils are self-assembled protein structures with important roles in biology (either pathogenic or physiological), and are attracting increasing interest in nanotechnology. However, because of their high aspect ratio and the presence of some polymorphism, that is, the possibility to adopt various structures, their characterization is challenging and basic information such as their mass is unknown. Here we show that charge-detection mass spectrometry, recently developed for large self-assembled systems such as viruses, provides such information in a straightforward manner. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mass and Energy: The Low-Energy Limit.

ERIC Educational Resources Information Center

Bauman, Robert P.

1994-01-01

Discusses Einstein's equation relating mass and energy highlighting these questions: (1) Can mass and energy be converted into one another? (2) What is the origin of the equation? (3) How do relativistic mass and rest mass relate? and (4) How is relativistic mass used in resulting equations? (MVL)

Association between fat mass, lean mass, and bone loss: the Dubbo Osteoporosis Epidemiology Study.

PubMed

Yang, S; Center, J R; Eisman, J A; Nguyen, T V

2015-04-01

Lower body fat mass is a risk factor for bone loss at lumbar spine in postmenopausal women, but not in men. Body lean mass and fat mass were not associated with femoral neck bone loss in either gender. Bone density and body mass are closely associated. Whole body lean mass (LM) and fat mass (FM) together account for approximately 95 % of body mass. Bone loss is associated with loss of body mass but which of the components of body mass (FM or LM) is related to bone loss is not well understood. Therefore, in this study, we sought to assess whether baseline FM or LM has predictive value for future relative rate of bone mineral density (BMD) changes (%/year). The present population-based cohort study was part of the ongoing Dubbo Osteoporosis Epidemiology Study (DOES). BMD, FM, and LM were measured with dual energy X-ray absorptiometry (GE-LUNAR Corp, Madison, WI). BMD measurements were taken in approximately every 2 years between 2000 and 2010. We only included the participants with at least two BMD measurements at the femoral neck and lumbar spine. In total, 717 individuals (204 men and 513 women) aged 50 years or older were studied. Rate of bone loss at femoral neck and lumbar spine was faster in women than in men (all P < 0.01). In bivariable regression analysis, each 5 kg greater FM in women was associated with 0.4 %/year (P = 0.003) lower bone loss at lumbar spine. This magnitude of association remained virtually unchanged after adjusting for LM and/or other covariates (P = 0.03). After adjusting for covariates, variation of FM accounted for ∼1.5 % total variation in lumbar spine bone loss. However, there was no significant association between FM and change in femoral neck BMD in either men or women. Lower FM was an independent but modest risk factor for greater bone loss at the lumbar spine in women but not in men. If further studies confirm our findings, FM can help predict lumbar spine bone loss in women.

The Mass of Large Impactors

NASA Technical Reports Server (NTRS)

Parisi, M. G.; Brunini, A.

1996-01-01

By means of a simplified dynamical model, we have computed the eccentricity change in the orbit of each giant planet, caused by a single, large impact at the end of the accretion process. In order to set an upper bound on this eccentricity change, we have considered the giant planets' present eccentricities as primordial ones. By means of this procedure, we were able to obtain an implicit relation for the impactor masses and maximum velocities. We have estimated by this method the maximum allowed mass to impact Jupiter to be approx. 1.136 x 10(exp -1), being in the case of Neptune approx. 3.99 x 10(exp -2) (expressed in units of each planet final mass). Due to the similar present eccentricities of Saturn, Uranus and Jupiter, the constraint masses and velocities of the bodies to impact them (in units of each planet final mass and velocity respectively) are almost the same for the three planets. These results are in good agreement with those obtained by Lissauer and Safronov. These bounds might be used to derive the mass distribution of planetesimals in the early solar system.

Intermediate-Mass Black Holes

NASA Astrophysics Data System (ADS)

Miller, M. Coleman; Colbert, E. J. M.

2004-01-01

The mathematical simplicity of black holes, combined with their links to some of the most energetic events in the universe, means that black holes are key objects for fundamental physics and astrophysics. Until recently, it was generally believed that black holes in nature appear in two broad mass ranges: stellar-mass (M~3 20 M⊙), which are produced by the core collapse of massive stars, and supermassive (M~106 1010 M⊙), which are found in the centers of galaxies and are produced by a still uncertain combination of processes. In the last few years, however, evidence has accumulated for an intermediate-mass class of black holes, with M~102 104 M⊙. If such objects exist they have important implications for the dynamics of stellar clusters, the formation of supermassive black holes, and the production and detection of gravitational waves. We review the evidence for intermediate-mass black holes and discuss future observational and theoretical work that will help clarify numerous outstanding questions about these objects.

Intermediate-Mass Black Holes

NASA Astrophysics Data System (ADS)

Coleman Miller, M.; Colbert, E. J. M.

The mathematical simplicity of black holes, combined with their links to some of the most energetic events in the universe, means that black holes are key objects for fundamental physics and astrophysics. Until recently, it was generally believed that black holes in nature appear in two broad mass ranges: stellar-mass (M~3-20 M⊙), which are produced by the core collapse of massive stars, and supermassive (M~106-1010 M⊙), which are found in the centers of galaxies and are produced by a still uncertain combination of processes. In the last few years, however, evidence has accumulated for an intermediate-mass class of black holes, with M~102-104 M⊙. If such objects exist they have important implications for the dynamics of stellar clusters, the formation of supermassive black holes, and the production and detection of gravitational waves. We review the evidence for intermediate-mass black holes and discuss future observational and theoretical work that will help clarify numerous outstanding questions about these objects.

Mass Separation by Metamaterials

PubMed Central

Restrepo-Flórez, Juan Manuel; Maldovan, Martin

2016-01-01

Being able to manipulate mass flow is critically important in a variety of physical processes in chemical and biomolecular science. For example, separation and catalytic systems, which requires precise control of mass diffusion, are crucial in the manufacturing of chemicals, crystal growth of semiconductors, waste recovery of biological solutes or chemicals, and production of artificial kidneys. Coordinate transformations and metamaterials are powerful methods to achieve precise manipulation of molecular diffusion. Here, we introduce a novel approach to obtain mass separation based on metamaterials that can sort chemical and biomolecular species by cloaking one compound while concentrating the other. A design strategy to realize such metamaterial using homogeneous isotropic materials is proposed. We present a practical case where a mixture of oxygen and nitrogen is manipulated using a metamaterial that cloaks nitrogen and concentrates oxygen. This work lays the foundation for molecular mass separation in biophysical and chemical systems through metamaterial devices. PMID:26912419

Pediatric head and neck masses.

PubMed

Gujar, Sachin; Gandhi, Dheeraj; Mukherji, Suresh K

2004-04-01

Most neck masses in the pediatric head and neck region are benign. Congenital, developmental, and inflammatory lesions make up most of the masses in the pediatric head and neck. For example, neck masses due to inflammatory lymphadenitis are common in children because of the frequency of upper respiratory tract infections. Although many of the malignant tumors in children are found in the head and neck, they account for only a small portion of the neck masses. The choice of the imaging modality is based on a number of factors, several of which are unique to the pediatric population. Although the bulk of disease entities are adequately evaluated by CT, MRI can provide additional vital information in many cases. MRI provides better soft tissue characterization than CT, has multiplanar capabilities. In this article, we will attempt to provide an overview of conditions that present as neck masses.

Mass loss and stellar superwinds.

PubMed

Vink, Jorick S

2017-10-28

Mass loss bridges the gap between massive stars and supernovae (SNe) in two major ways: (i) theoretically, it is the amount of mass lost that determines the mass of the star prior to explosion and (ii) observations of the circumstellar material around SNe may teach us the type of progenitor that made the SN. Here, I present the latest models and observations of mass loss from massive stars, both for canonical massive O stars, as well as very massive stars that show Wolf-Rayet type features.This article is part of the themed issue 'Bridging the gap: from massive stars to supernovae'. © 2017 The Author(s).

Galaxy Cluster Mass Reconstruction Project – III. The impact of dynamical substructure on cluster mass estimates

DOE PAGES

Old, L.; Wojtak, R.; Pearce, F. R.; ...

2017-12-20

With the advent of wide-field cosmological surveys, we are approaching samples of hundreds of thousands of galaxy clusters. While such large numbers will help reduce statistical uncertainties, the control of systematics in cluster masses is crucial. Here we examine the effects of an important source of systematic uncertainty in galaxy-based cluster mass estimation techniques: the presence of significant dynamical substructure. Dynamical substructure manifests as dynamically distinct subgroups in phase-space, indicating an ‘unrelaxed’ state. This issue affects around a quarter of clusters in a generally selected sample. We employ a set of mock clusters whose masses have been measured homogeneously withmore » commonly used galaxy-based mass estimation techniques (kinematic, richness, caustic, radial methods). We use these to study how the relation between observationally estimated and true cluster mass depends on the presence of substructure, as identified by various popular diagnostics. We find that the scatter for an ensemble of clusters does not increase dramatically for clusters with dynamical substructure. However, we find a systematic bias for all methods, such that clusters with significant substructure have higher measured masses than their relaxed counterparts. This bias depends on cluster mass: the most massive clusters are largely unaffected by the presence of significant substructure, but masses are significantly overestimated for lower mass clusters, by ~ 10 percent at 10 14 and ≳ 20 percent for ≲ 10 13.5. Finally, the use of cluster samples with different levels of substructure can therefore bias certain cosmological parameters up to a level comparable to the typical uncertainties in current cosmological studies.« less

Galaxy Cluster Mass Reconstruction Project – III. The impact of dynamical substructure on cluster mass estimates

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

Old, L.; Wojtak, R.; Pearce, F. R.

With the advent of wide-field cosmological surveys, we are approaching samples of hundreds of thousands of galaxy clusters. While such large numbers will help reduce statistical uncertainties, the control of systematics in cluster masses is crucial. Here we examine the effects of an important source of systematic uncertainty in galaxy-based cluster mass estimation techniques: the presence of significant dynamical substructure. Dynamical substructure manifests as dynamically distinct subgroups in phase-space, indicating an ‘unrelaxed’ state. This issue affects around a quarter of clusters in a generally selected sample. We employ a set of mock clusters whose masses have been measured homogeneously withmore » commonly used galaxy-based mass estimation techniques (kinematic, richness, caustic, radial methods). We use these to study how the relation between observationally estimated and true cluster mass depends on the presence of substructure, as identified by various popular diagnostics. We find that the scatter for an ensemble of clusters does not increase dramatically for clusters with dynamical substructure. However, we find a systematic bias for all methods, such that clusters with significant substructure have higher measured masses than their relaxed counterparts. This bias depends on cluster mass: the most massive clusters are largely unaffected by the presence of significant substructure, but masses are significantly overestimated for lower mass clusters, by ~ 10 percent at 10 14 and ≳ 20 percent for ≲ 10 13.5. Finally, the use of cluster samples with different levels of substructure can therefore bias certain cosmological parameters up to a level comparable to the typical uncertainties in current cosmological studies.« less

Survey of Mass Storage Systems

DTIC Science & Technology

1975-09-01

software that Pre- cision Instruments can provide. System Name: IBM 3850 Mass Storage System Manufacturer and Location: International Business Machines...34 Datamation, pp. 52-58, October 1973. 15 17. International Business Machines, IBM 3850 Mass Storage System Facts Folder, White Plains, NY, n.d. 18... International Business Machines, Introduction to the IBM 3850 Mass Storage System (MSS), White Plains, NY, n.d. 19. International Business Machines

Mass-tag enhanced immuno-laser desorption/ionization mass spectrometry for sensitive detection of intact protein antigens.

PubMed

Lorey, Martina; Adler, Belinda; Yan, Hong; Soliymani, Rabah; Ekström, Simon; Yli-Kauhaluoma, Jari; Laurell, Thomas; Baumann, Marc

2015-05-19

A new read-out method for antibody arrays using laser desorption/ionization-mass spectrometry (LDI-MS) is presented. Small, photocleavable reporter molecules with a defined mass called "mass-tags" are used for detection of immunocaptured proteins from human plasma. Using prostate specific antigen (PSA), a biomarker for prostate cancer, as a model antigen, a high sensitivity generic detection methodology based immunocapture with a primary antibody and with a biotin labeled secondary antibody coupled to mass-tagged avidin is demonstrated. As each secondary antibody can bind several avidin molecules, each having a large number of mass-tags, signal amplification can be achieved. The developed PSA sandwich mass-tag analysis method provided a limit of detection below 200 pg/mL (6 pM) for a 10 μL plasma sample, well below the clinically relevant cutoff value of 3-4 ng/mL. This brings the limit of detection (LOD) for detection of intact antigens with matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) down to levels comparable to capture by anti-peptide antibodies selected reaction monitoring (SISCAPA SRM) and enzyme linked immunosorbent assay (ELISA), as 6 pM corresponds to a maximal amount of 60 amol PSA captured on-spot. We propose the potential use of LDI (laser desorption/ionization) with mass-tag read-out implemented in a sandwich assay format for low abundant and/or early disease biomarker detection.

High-precision mass measurements for the isobaric multiplet mass equation at A = 52

NASA Astrophysics Data System (ADS)

Nesterenko, D. A.; Kankainen, A.; Canete, L.; Block, M.; Cox, D.; Eronen, T.; Fahlander, C.; Forsberg, U.; Gerl, J.; Golubev, P.; Hakala, J.; Jokinen, A.; Kolhinen, V. S.; Koponen, J.; Lalović, N.; Lorenz, Ch; Moore, I. D.; Papadakis, P.; Reinikainen, J.; Rinta-Antila, S.; Rudolph, D.; Sarmiento, L. G.; Voss, A.; Äystö, J.

2017-06-01

Masses of 52Co, 52Co m , 52Fe, 52Fe m , and 52Mn have been measured with the JYFLTRAP double Penning trap mass spectrometer. The isobaric multiplet mass equation for the T = 2 quintet at A = 52 has been studied employing the new mass values. No significant breakdown (beyond the 3σ level) of the quadratic form of the IMME was observed ({χ }2/n=2.4). The cubic coefficient was 6.0(32) keV ({χ }2/n=1.1). The excitation energies for the isomer and the T = 2 isobaric analog state in 52Co have been determined to be 374(13) keV and 2922(13) keV, respectively. The measured mass values for 52Co and 52Co m are 29(10) keV and 16(15) keV higher, respectively, than obtained in a recent storage-ring experiment, and significantly lower than predicted by extrapolations. Consequently, this has an impact on the proton separation energies for 52Co and 53Ni relevant for the astrophysical rapid proton capture process. The Q value for the proton decay from the 19/{2}- isomer in 53Co has been determined with an unprecedented precision, {Q}p=1558.8(17) keV.

Quark ACM with topologically generated gluon mass

NASA Astrophysics Data System (ADS)

Choudhury, Ishita Dutta; Lahiri, Amitabha

2016-03-01

We investigate the effect of a small, gauge-invariant mass of the gluon on the anomalous chromomagnetic moment (ACM) of quarks by perturbative calculations at one-loop level. The mass of the gluon is taken to have been generated via a topological mass generation mechanism, in which the gluon acquires a mass through its interaction with an antisymmetric tensor field Bμν. For a small gluon mass ( < 10 MeV), we calculate the ACM at momentum transfer q2 = -M Z2. We compare those with the ACM calculated for the gluon mass arising from a Proca mass term. We find that the ACM of up, down, strange and charm quarks vary significantly with the gluon mass, while the ACM of top and bottom quarks show negligible gluon mass dependence. The mechanism of gluon mass generation is most important for the strange quarks ACM, but not so much for the other quarks. We also show the results at q2 = -m t2. We find that the dependence on gluon mass at q2 = -m t2 is much less than at q2 = -M Z2 for all quarks.

Mass loss from solar-type stars

NASA Technical Reports Server (NTRS)

Hartmann, L.

1985-01-01

The present picture of mass loss from solar-type (low-mass) stars is described, with special emphasis on winds from pre-main-sequence stars. Attention is given to winds from T Tauri stars and to angular momentum loss. Prospects are good for further advances in our understanding of the powerful mass loss observed from young stars; ultraviolet spectra obtainable with the Space Telescope should provide better estimates of mass loss rates and a clearer picture of physical conditions in the envelopes of these stars. To understand the mass ejection from old, slowly rotating main-sequence stars, we will have to study the sun.

The discrepancy between dynamical and theoretical mass in the triplet-system 2MASS J10364483+1521394

NASA Astrophysics Data System (ADS)

Calissendorff, Per; Janson, Markus; Köhler, Rainer; Durkan, Stephen; Hippler, Stefan; Dai, Xiaolin; Brandner, Wolfgang; Schlieder, Joshua; Henning, Thomas

2017-08-01

We combine new Lucky Imaging astrometry from New Technology Telescope/AstraLux Sur with already published astrometry from the AstraLux Large M-dwarf Multiplicity Survey to compute orbital elements and individual masses of the 2MASS J10364483+1521394 triple system belonging to the Ursa-Major moving group. The system consists of one primary low-mass M-dwarf orbited by two less massive companions, for which we determine a combined dynamical mass of MB + C = 0.48 ± 0.14 M⊙. We show from the companions' relative motions that they are of equal mass (with a mass ratio of 1.00 ± 0.03), thus 0.24 ± 0.07 M⊙ individually, with a separation of 3.2 ± 0.3 AU, and we conclude that these masses are significantly higher (30%) than what is predicted by theoretical stellar evolutionary models. The biggest uncertainty remains the distance to the system, here adopted as 20.1 ± 2.0 pc based on trigonometric parallax, whose ambiguity has a major impact on the result. With the new observational data we are able to conclude that the orbital period of the BC pair is 8.41+0.04-0.02yr.

Reactions of Ions with Ionic Liquid Vapors by Selected-Ion Flow Tube Mass Spectrometry

DTIC Science & Technology

2011-03-04

Internet at http://pubs.acs.org. References (1) Emel’yanenko, V. N.; Verevkin, S. P.; Heintz, A.; Corfield, J.-A.; Deyko, A.; Lovelock , K. R. J...Spectrometry, and ab Initio Calculations J. Phys. Chem. B 2008, 112, 11734-11742. (2) Lovelock , K. R. J.; Deyko, A.; Licence, P.; Jones, R. G. Vaporisation of...Licence, P.; Lovelock , K. R. J.; Satterly, C. J.; Villar-Garcia, I. J. Vapourisation of ionic liquids PCCP 2007, 9, 982-990. (14) Chiu, Y.-H

Reactions of Ions with Ionic Liquid Vapors by Selected-Ion Flow Tube Mass Spectrometry

DTIC Science & Technology

2011-03-29

Emel’yanenko, V. N.; Verevkin, S. P.; Heintz, A.; Corfield, J.-A.; Deyko, A.; Lovelock , K. R. J.; Licence, P.; Jones, R. G. Pyrrolidinium- Based Ionic...112, 11734–11742. (2) Lovelock , K. R. J.; Deyko, A.; Licence, P.; Jones, R. G. Vaporisa- tion of an Ionic Liquid Near Room Temperature. Phys. Chem...Relevance of pKa from Aqueous Solutions. J. Am. Chem. Soc. 2003, 125, 15411–15419. (15) Armstrong, J. P.; Hurst, C.; Jones, R. G.; Licence, P.; Lovelock , K

USING AN ACCURATE MASS, TRIPLE QUADRUPOLE MASS SPECTROMETER AND AN ION CORRELATION PROGRAM TO IDENTIFY COMPOUNDS

EPA Science Inventory

Most compounds are not found in mass spectral libraries and must be identified by other means. Often, compound identities can be deduced from the compositions of the ions in their mass spectra and review of the chemical literature. Confirmation is provided by mass spectra and r...

Absorption Mode FT-ICR Mass Spectrometry Imaging

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

Smith, Donald F.; Kilgour, David P.; Konijnenburg, Marco

2013-12-03

Fourier transform ion cyclotron resonance mass spectrometry offers the highest mass resolving power for molecular imaging experiments. This high mass resolving power ensures that closely spaced peaks at the same nominal mass are resolved for proper image generation. Typically higher magnetic fields are used to increase mass resolving power. However, a gain in mass resolving power can also be realized by phase correction of the data for absorption mode display. In addition to mass resolving power, absorption mode offers higher mass accuracy and signal-to-noise ratio over the conventional magnitude mode. Here we present the first use of absorption mode formore » Fourier transform ion cyclotron resonance mass spectrometry imaging. The Autophaser algorithm is used to phase correct each spectrum (pixel) in the image and then these parameters are used by the Chameleon work-flow based data processing software to generate absorption mode ?Datacubes? for image and spectral viewing. Absorption mode reveals new mass and spatial features that are not resolved in magnitude mode and results in improved selected ion image contrast.« less

Determining Gravitational Attraction by Mass Property Measurements

NASA Astrophysics Data System (ADS)

Swank, Aaron J.; Sun, Ke-Xun; DeBra, Dan

2006-11-01

The acceleration generated by the gradient of the mass attraction field between the spacecraft and proof mass is one parameter critical to drag-free performance. The gravitational self-attraction properties between two distributed bodies is characterized by the mass, mass center and moment of inertia for each body. Mass property measurements can therefore be used to indirectly measure the mass attraction properties. Since the ultimate goal is to demonstrate the ability to predict the system gravitational mass attraction force and force gradients to a precision below that of the LISA requirements, the corresponding properties of mass, mass center, and moment of inertia must be precisely determined for the proof mass and satellite components. This work introduces a new method for measuring the moment of inertia using a novel five-wire torsion pendulum, which reduces errors due to translational degrees of freedom. The five-wire pendulum is integrated with optical angular sensing using diffraction grating angular magnification to provide a sensor with both a large dynamic range and high resolution.

Micromechanical Oscillating Mass Balance

NASA Technical Reports Server (NTRS)

Altemir, David A. (Inventor)

1997-01-01

A micromechanical oscillating mass balance and method adapted for measuring minute quantities of material deposited at a selected location, such as during a vapor deposition process. The invention comprises a vibratory composite beam which includes a dielectric layer sandwiched between two conductive layers. The beam is positioned in a magnetic field. An alternating current passes through one conductive layers, the beam oscillates, inducing an output current in the second conductive layer, which is analyzed to determine the resonant frequency of the beam. As material is deposited on the beam, the mass of the beam increases and the resonant frequency of the beam shifts, and the mass added is determined.

The mass-lifetime relation

NASA Astrophysics Data System (ADS)

LoPresto, Michael C.

2018-05-01

In a recent "AstroNote," I described a simple exercise on the mass-luminosity relation for main sequence stars as an example of exposing students in a general education science course of lower mathematical level to the use of quantitative skills such as collecting and analyzing data. Here I present another attempt at a meaningful experience for such students that again involves both the gathering and analysis of numerical data and comparison with accepted result, this time on the relationship of the mass and lifetimes of main sequence stars. This experiment can stand alone or be used as an extension of the previous mass-luminosity relationship experiment.

Determination of balloon gas mass and revised estimates of drag and virtual mass coefficients

NASA Technical Reports Server (NTRS)

Robbins, E.; Martone, M.

1993-01-01

In support of the NASA Balloon Program, small-scale balloons were flown with varying lifting gas and total system mass. Instrument packages were developed to measure and record acceleration and temperature data during these tests. Top fitting and instrument payload accelerations were measured from launch to steady state ascent and through ballast drop transients. The development of the small lightweight self-powered Stowaway Special instrument packages is discussed along with mathematical models developed to determine gas mass, drag and virtual mass coefficients.

Differences in distal lower extremity tissue masses and mass ratios exist in athletes of sports involving repetitive impacts.

PubMed

Schinkel-Ivy, Alison; Burkhart, Timothy A; Andrews, David M

2014-01-01

This study aimed to examine the effects of sex and sport on the tissue composition of the distal lower extremity of varsity athletes, in sports that involve repetitive-impact loading patterns. Fat mass, lean mass, bone mineral content and wobbling mass were predicted for the leg and leg + foot segments of varsity basketball, cross-country, soccer and volleyball athletes. The absolute masses were normalised to body mass, and also expressed relative to each other as ratios. Females and males differed on most normalised tissue masses and ratios by 11-101%. Characteristic differences were found in the normalised tissue masses across sports, with the lowest and highest values displayed by cross-country and volleyball (female)/basketball (male) athletes, respectively. Conversely, cross-country athletes had the highest wobbling mass:bone mineral content and lean mass:bone mineral content ratios for females by 10% and 16%, respectively. The differences between sports may be explained in part by different impact loading patterns characteristic of each sport. Tissue mass ratio differences between sports may suggest that the ratios of soft to rigid tissues are optimised by the body in response to typical loading patterns, and may therefore be useful in investigations of distal lower extremity injury mechanisms in athletes.

Water Vapour Effects in Mass Measurement

NASA Astrophysics Data System (ADS)

Khélifa, N.

2008-01-01

Water vapour density inside the mass comparator enclosure is a critical parameter whose fluctuations during mass weighing can lead to errors in the determination of an unknown mass. To monitor them, a method using DFB laser diode in the near infrared has been proposed and tested. Preliminary results of our observation of water vapour sorption and de-sorption processes from the walls and the mass standard are reported.

Masses of Nix and Hydra

NASA Astrophysics Data System (ADS)

Tholen, David J.; Buie, M. W.; Grundy, W.

2007-05-01

Two new, small satellites of Pluto were discovered in 2005 using deep images from the Hubble Space Telescope. The IAU has approved the name Hydra for the outermost satellite and the name Nix for the one orbiting at an intermediate distance between Charon and Hydra. We used the two discovery observations of Nix and Hydra from 2005, the two confirmation observations from 2006, and the twelve prediscovery observations from 2001 and 2002, as well as available observations of Charon, to perform a four-body orbit solution for the Pluto system. Mutual perturbations have placed constraints on the masses of each member of the system. Previous work placed useful limits on the masses of Pluto and Charon, as well as their densities, given the known sizes of the bodies based on stellar occultation and mutual event observations, therefore our new work is aimed at placing constraints on the masses of Nix and Hydra. The best-fit GM values for Nix and Hydra are 0.040 and 0.021 km3 sec-2. The uncertainty in the GM of Hydra is large enough to allow for a negligible mass. At the one-sigma level, we can rule out masses near the upper limit of what is physically reasonable (correpsonding to a combination of low albedos and high densities) for both satellites, and in the case of Nix, we can also rule out a mass near the lower limit (corresponding to a high albedo and low density). We have determined empirically that the rate of precession of the line of apsides of Charon's slightly eccentric orbit is proportional to the mass of Nix and Hydra. New HST observations of the satellites are scheduled, which should improve the orbit solution and reduce the uncertainties in the masses. Ultimately, these results will place constraints on models for the formation of the system.

FOREWORD: Special issue on mass

NASA Astrophysics Data System (ADS)

Gläser, Michael

2003-12-01

This special issue is intended to present a review of mass standards, mass determination and the efforts to replace the international prototype of the kilogram by a new definition of the kilogram based on a fundamental constant of physics. Mass is a quantity that is familiar to everybody primarily for its importance in commerce. It is not only one of the traditional quantities of metrology but also of science in general. The unit of mass has always been based on a material object and, since 1889, on the international prototype of the kilogram. The mass of any standard weight is derived from this prototype by a cascade of comparison measurements using balances. The sources of uncertainty of the mass of a standard depend upon the circumstances of the weighing process and the long-term instabilities of the intermediate standards. The international prototype—its mass is one kilogram by definition—may also suffer from instabilities or drifts in time, but until now it has not been possible to check this by comparison with a fundamental constant in physics. Repeated verifications of some 40 or so national prototypes of the members of the Metre Convention have shown significant drifts with an average of about 50 µg within 100 years, a fact that casts doubt on the stability of the international prototype itself. Experiments have been underway for about 30 years on linking fundamental constants such as the Avogadro constant or, correspondingly, the atomic mass unit and Planck's constant to the kilogram. Relative uncertainties of the order of 10-7 have been reached today, still one order of magnitude too large for monitoring the stability of the international prototype or for a new definition. The first article of this special issue gives information on the international and the national prototypes of the kilogram, its material, manufacture, cleaning procedures, stability investigations and the periodic verifications of national prototypes. The next article describes

RESOLVE AND ECO: THE HALO MASS-DEPENDENT SHAPE OF GALAXY STELLAR AND BARYONIC MASS FUNCTIONS

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

Eckert, Kathleen D.; Kannappan, Sheila J.; Stark, David V.

2016-06-20

In this work, we present galaxy stellar and baryonic (stars plus cold gas) mass functions (SMF and BMF) and their halo mass dependence for two volume-limited data sets. The first, RESOLVE-B, coincides with the Stripe 82 footprint and is extremely complete down to baryonic mass M {sub bary} ∼ 10{sup 9.1} M {sub ⊙}, probing the gas-rich dwarf regime below M {sub bary} ∼ 10{sup 10} M {sub ⊙}. The second, ECO, covers a ∼40× larger volume (containing RESOLVE-A) and is complete to M {sub bary} ∼ 10{sup 9.4} M {sub ⊙}. To construct the SMF and BMF we implementmore » a new “cross-bin sampling” technique with Monte Carlo sampling from the full likelihood distributions of stellar or baryonic mass. Our SMFs exhibit the “plateau” feature starting below M {sub star} ∼ 10{sup 10} M {sub ⊙} that has been described in prior work. However, the BMF fills in this feature and rises as a straight power law below ∼10{sup 10} M {sub ⊙}, as gas-dominated galaxies become the majority of the population. Nonetheless, the low-mass slope of the BMF is not as steep as that of the theoretical dark matter halo MF. Moreover, we assign group halo masses by abundance matching, finding that the SMF and BMF, separated into four physically motivated halo mass regimes, reveal complex structure underlying the simple shape of the overall MFs. In particular, the satellite MFs are depressed below the central galaxy MF “humps” in groups with mass <10{sup 13.5} M {sub ⊙} yet rise steeply in clusters. Our results suggest that satellite destruction and stripping are active from the point of nascent group formation. We show that the key role of groups in shaping MFs enables reconstruction of a given survey’s SMF or BMF based on its group halo mass distribution.« less

Mass Spectrometer Containing Multiple Fixed Collectors

NASA Technical Reports Server (NTRS)

Moskala, Robert; Celo, Alan; Voss, Guenter; Shaffer, Tom

2008-01-01

A miniature mass spectrometer that incorporates features not typically found in prior mass spectrometers is undergoing development. This mass spectrometer is designed to simultaneously measure the relative concentrations of five gases (H2, He, N2, O2, and Ar) in air, over the relative-concentration range from 10(exp -6) to 1, during a sampling time as short as 1 second. It is intended to serve as a prototype of a product line of easy-to-use, portable, lightweight, highspeed, relatively inexpensive instruments for measuring concentrations of multiple chemical species in such diverse applications as detecting explosive or toxic chemicals in air, monitoring and controlling industrial processes, measuring concentrations of deliberately introduced isotopes in medical and biological investigations, and general environmental monitoring. The heart of this mass spectrometer is an integral combination of a circular cycloidal mass analyzer, multiple fixed ion collectors, and two mass-selective ion sources. By circular cycloidal mass analyzer is meant an analyzer that includes (1) two concentric circular cylindrical electrodes for applying a radial electric field and (2) a magnet arranged to impose a magnetic flux aligned predominantly along the cylindrical axis, so that ions, once accelerated into the annulus between the electrodes, move along circular cycloidal trajectories. As in other mass analyzers, trajectory of each ion is determined by its mass-to-charge ratio, and so ions of different species can be collected simultaneously by collectors (Faraday cups) at different locations intersected by the corresponding trajectories (see figure). Unlike in other mass analyzers, the installation of additional collectors to detect additional species does not necessitate increasing the overall size of the analyzer assembly.

The Mass Function of Cosmic Structures

NASA Astrophysics Data System (ADS)

Audit, E.; Teyssier, R.; Alimi, J.-M.

We investigate some modifications to the Press and Schechter (1974) (PS) prescription resulting from shear and tidal effects. These modifications rely on more realistic treatments of the collapse process than the standard approach based on the spherical model. First, we show that the mass function resulting from a new approximate Lagrangian dynamic (Audit and Alimi, A&A 1996), contains more objects at high mass, than the classical PS mass function and is well fitted by a PS-like function with a threshold density of deltac ≍ 1.4. However, such a Lagrangian description can underestimate the epoch of structure formation since it defines it as the collapse of the first principal axis. We therefore suggest some analytical prescriptions, for computing the collapse time along the second and third principal axes, and we deduce the corresponding mass functions. The collapse along the third axis is delayed by the shear and the number of objects of high mass then decreases. Finally, we show that the shear also strongly affects the formation of low-mass halos. This dynamical effect implies a modification of the low-mass slope of the mass function and allows the reproduction of the observed luminosity function of field galaxies.

Air Pressure Controlled Mass Measurement System

NASA Astrophysics Data System (ADS)

Zhong, Ruilin; Wang, Jian; Cai, Changqing; Yao, Hong; Ding, Jin'an; Zhang, Yue; Wang, Xiaolei

Mass measurement is influenced by air pressure, temperature, humidity and other facts. In order to reduce the influence, mass laboratory of National Institute of Metrology, China has developed an air pressure controlled mass measurement system. In this system, an automatic mass comparator is installed in an airtight chamber. The Chamber is equipped with a pressure controller and associate valves, thus the air pressure can be changed and stabilized to the pre-set value, the preferred pressure range is from 200 hPa to 1100 hPa. In order to keep the environment inside the chamber stable, the display and control part of the mass comparator are moved outside the chamber, and connected to the mass comparator by feed-throughs. Also a lifting device is designed for this system which can easily lift up the upper part of the chamber, thus weights can be easily put inside the mass comparator. The whole system is put on a marble platform, and the temperature and humidity of the laboratory is very stable. The temperature, humidity, and carbon dioxide content inside the chamber are measured in real time and can be used to get air density. Mass measurement cycle from 1100 hPa to 200 hPa and back to 1100 hPa shows the effective of the system.

Finding Mass Constraints Through Third Neutrino Mass Eigenstate Decay

NASA Astrophysics Data System (ADS)

Gangolli, Nakul; de Gouvêa, André; Kelly, Kevin

2018-01-01

In this paper we aim to constrain the decay parameter for the third neutrino mass utilizing already accepted constraints on the other mixing parameters from the Pontecorvo-Maki-Nakagawa-Sakata matrix (PMNS). The main purpose of this project is to determine the parameters that will allow the Jiangmen Underground Neutrino Observatory (JUNO) to observe a decay parameter with some statistical significance. Another goal is to determine the parameters that JUNO could detect in the case that the third neutrino mass is lighter than the first two neutrino species. We also replicate the results that were found in the JUNO Conceptual Design Report (CDR). By utilizing Χ2-squared analysis constraints have been put on the mixing angles, mass squared differences, and the third neutrino decay parameter. These statistical tests take into account background noise and normalization corrections and thus the finalized bounds are a good approximation for the true bounds that JUNO can detect. If the decay parameter is not included in our models, the 99% confidence interval lies within The bounds 0s to 2.80x10-12s. However, if we account for a decay parameter of 3x10-5 ev2, then 99% confidence interval lies within 8.73x10-12s to 8.73x10-11s.

Management of mass casualty: a review.

PubMed

Adesunkanmi, A R K; Lawal, A O

2011-09-01

The aim of this article is to discuss the management of mass casualty and sensitise authorities at various levels and trauma surgeons the need for awareness and training in the management of mass casualty. Thorough Medline and bibliography search and available local literatures relevant to the management of mass casualty was reviewed. The available articles were reviewed in order to decipher the management pattern in various forms and degree of disasters resulting in mass casualty. Little attention was paid to mass casualty management in civilian population until mid nineties, even, in developed countries. Knowledge in this area has expanded in the last 10 years due to terrorist attacks in the United State America. In developing countries, nothing is known to be on the ground in form of planning for appropriate response to mass casualty. Mass casualty usually associated with straining of existing facilities, and with high morbidity and mortality. Pre-incident and adequate training is necessary to reduce morbidity and mortality from major incident which occurrence is often not predictable.

Stochastic mass-reconstruction: a new technique to reconstruct resonance masses of heavy particles decaying into tau lepton pairs

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

Maruyama, Sho

2015-12-15

The invariant mass of tau lepton pairs turns out to be smaller than the resonant mass of their mother particle and the invariant mass distribution is stretched wider than the width of the resonant mass as significant fraction of tau lepton momenta are carried away by neutrinos escaping undetected at collider experiments. This paper describes a new approach to reconstruct resonant masses of heavy particles decaying to tau leptons at such experiments. A typical example is a Z or Higgs boson decaying to a tau pair. Although the new technique can be used for each tau lepton separately, I combinemore » two tau leptons to improve mass resolution by requiring the two tau leptons are lined up in a transverse plane. The method is simple to implement and complementary to the collinear approximation technique that works well when tau leptons are not lined up in a transverse plane. The reconstructed mass can be used as another variable in analyses that already use a visible tau pair mass and missing transverse momentum as these variables are not explicitly used in the stochastic mass-reconstruction to select signal-like events.« less

Mass selective separation applied to radioisotopes of cesium: Mass selective applied to radioisotopes

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

Dion, Michael; Eiden, Greg; Farmer, Orville

2016-07-22

A developed technique that uses the intrinsic mass-based separation capability of a quadrupole mass spectrometer has been used to resolve spectral radiometric interference of two isotopes of the same element. In this work the starting sample was a combination of 137Cs and 134Cs and was (activity) dominated by 137Cs and this methodology separated and “implanted” 134Cs that was later quantified for spectral features and ac- tivity with traditional radiometric techniques. This work demonstrated a 134Cs/137Cs activity ratio enhancement of >4 orders of magnitude and complete removal of 137Cs spectral features from the implanted target mass (i.e., 134).

Variation in body mass dynamics among sites in Black Brant Branta bernicla nigricans supports adaptivity of mass loss during moult

USGS Publications Warehouse

Fondell, Thomas F.; Flint, Paul L.; Schmutz, Joel A.; Schamber, Jason L.; Nicolai, Christopher A.

2013-01-01

Birds employ varying strategies to accommodate the energetic demands of moult, one important example being changes in body mass. To understand better their physiological and ecological significance, we tested three hypotheses concerning body mass dynamics during moult. We studied Black Brant in 2006 and 2007 moulting at three sites in Alaska which varied in food availability, breeding status and whether geese undertook a moult migration. First we predicted that if mass loss during moult were simply the result of inadequate food resources then mass loss would be highest where food was least available. Secondly, we predicted that if mass loss during moult were adaptive, allowing birds to reduce activity during moult, then birds would gain mass prior to moult where feeding conditions allowed and mass loss would be positively related to mass at moult initiation. Thirdly, we predicted that if mass loss during moult were adaptive, allowing birds to regain flight sooner, then across sites and groups, mass at the end of the flightless period would converge on a theoretical optimum, i.e. the mass that permits the earliest possible return to flight. Mass loss was greatest where food was most available and thus our results did not support the prediction that mass loss resulted from inadequate food availability. Mass at moult initiation was positively related to both food availability and mass loss. In addition, among sites and years, variation in mass was high at moult initiation but greatly reduced at the end of the flightless period, appearing to converge. Thus, our results supported multiple predictions that mass loss during moult was adaptive and that the optimal moulting strategy was to gain mass prior to the flightless period, then through behavioural modifications use these body reserves to reduce activity and in so doing also reduce wing loading. Geese that undertook a moult migration initiated moult at the highest mass, indicating that they were more than able to

Parsimonious Charge Deconvolution for Native Mass Spectrometry

PubMed Central

2018-01-01

Charge deconvolution infers the mass from mass over charge (m/z) measurements in electrospray ionization mass spectra. When applied over a wide input m/z or broad target mass range, charge-deconvolution algorithms can produce artifacts, such as false masses at one-half or one-third of the correct mass. Indeed, a maximum entropy term in the objective function of MaxEnt, the most commonly used charge deconvolution algorithm, favors a deconvolved spectrum with many peaks over one with fewer peaks. Here we describe a new “parsimonious” charge deconvolution algorithm that produces fewer artifacts. The algorithm is especially well-suited to high-resolution native mass spectrometry of intact glycoproteins and protein complexes. Deconvolution of native mass spectra poses special challenges due to salt and small molecule adducts, multimers, wide mass ranges, and fewer and lower charge states. We demonstrate the performance of the new deconvolution algorithm on a range of samples. On the heavily glycosylated plasma properdin glycoprotein, the new algorithm could deconvolve monomer and dimer simultaneously and, when focused on the m/z range of the monomer, gave accurate and interpretable masses for glycoforms that had previously been analyzed manually using m/z peaks rather than deconvolved masses. On therapeutic antibodies, the new algorithm facilitated the analysis of extensions, truncations, and Fab glycosylation. The algorithm facilitates the use of native mass spectrometry for the qualitative and quantitative analysis of protein and protein assemblies. PMID:29376659

Determination of SB2 masses and age: introduction of the mass ratio in the Bayesian analysis

NASA Astrophysics Data System (ADS)

Giarrusso, M.; Leone, F.; Tognelli, E.; Degl'Innocenti, S.; Prada Moroni, P. G.

2018-04-01

Stellar age assignment still represents a difficult task in Astrophysics. This unobservable fundamental parameter can be estimated only through indirect methods, as well as generally the mass. Bayesian analysis is a statistical approach largely used to derive stellar properties by taking into account the available information about the quantities we are looking for. In this paper we propose to apply the method to the double-lined spectroscopic binaries (SB2), for which the only available information about masses is the observed mass ratio of the two components. We validated the method on a synthetic sample of Pre-Main Sequence (PMS) SB2 systems showing the capability of the technique to recover the simulated age and masses. Then, we applied our procedure to the PMS eclipsing binaries Parenago 1802 and RX J0529.4+0041 A, whose masses of both components are known, by treating them as SB2 systems. The estimated masses are in agreement with those dynamically measured. We conclude that the method, if based on high resolution and high signal-to-noise spectroscopy, represents a robust way to infer the masses of the very numerous SB2 systems together with their age, allowing to date the hosting astrophysical environments.

Determination of SB2 masses and age: introduction of the mass ratio in the Bayesian analysis

NASA Astrophysics Data System (ADS)

Giarrusso, M.; Leone, F.; Tognelli, E.; Degl'Innocenti, S.; Prada Moroni, P. G.

2018-07-01

Stellar age assignment still represents a difficult task in Astrophysics. This unobservable fundamental parameter can be estimated only through indirect methods, as well as generally the mass. Bayesian analysis is a statistical approach largely used to derive stellar properties by taking into account the available information about the quantities we are looking for. In this paper, we propose to apply the method to the double-lined spectroscopic binaries (SB2), for which the only available information about masses is the observed mass ratio of the two components. We validated the method on a synthetic sample of pre-main-sequence (PMS) SB2 systems showing the capability of the technique to recover the simulated age and masses. Then, we applied our procedure to the PMS eclipsing binaries Parenago 1802 and RX J0529.4+0041 A, whose masses of both components are known, by treating them as SB2 systems. The estimated masses are in agreement with those dynamically measured. We conclude that the method, if based on high resolution and high signal-to-noise spectroscopy, represents a robust way to infer the masses of the very numerous SB2 systems together with their age, allowing to date the hosting astrophysical environments.

Mass spectrometry of atmospheric aerosols--recent developments and applications. Part II: On-line mass spectrometry techniques.

PubMed

Pratt, Kerri A; Prather, Kimberly A

2012-01-01

Many of the significant advances in our understanding of atmospheric particles can be attributed to the application of mass spectrometry. Mass spectrometry provides high sensitivity with fast response time to probe chemically complex particles. This review focuses on recent developments and applications in the field of mass spectrometry of atmospheric aerosols. In Part II of this two-part review, we concentrate on real-time mass spectrometry techniques, which provide high time resolution for insight into brief events and diurnal changes while eliminating the potential artifacts acquired during long-term filter sampling. In particular, real-time mass spectrometry has been shown recently to provide the ability to probe the chemical composition of ambient individual particles <30 nm in diameter to further our understanding of how particles are formed through nucleation in the atmosphere. Further, transportable real-time mass spectrometry techniques are now used frequently on ground-, ship-, and aircraft-based studies around the globe to further our understanding of the spatial distribution of atmospheric aerosols. In addition, coupling aerosol mass spectrometry techniques with other measurements in series has allowed the in situ determination of chemically resolved particle effective density, refractive index, volatility, and cloud activation properties. Copyright © 2011 Wiley Periodicals, Inc.

Gravity-induced rock mass damage related to large en masse rockslides: Evidence from Vajont

NASA Astrophysics Data System (ADS)

Paronuzzi, Paolo; Bolla, Alberto

2015-04-01

The Vajont landslide is a well-known, reservoir-induced slope failure that occurred on 9 October 1963 and was characterized by an 'en masse' sliding motion that triggered various large waves, determining catastrophic consequences for the nearby territory and adjacent villages. During the Vajont dam construction, and especially after the disaster, some researchers identified widespread field evidence of heavy rock mass damage involving the presumed prehistoric rockslide and/or the 1963 failed mass. This paper describes evidence of heavy gravitational damage, including (i) folding, (ii) fracturing, (iii) faulting, and (iv) intact rock disintegration. The gravity-induced rock mass damage (GRMD) characterizes the remnants of the basal shear zone, still resting on the large detachment surface, and the 1963 failed rock mass. The comprehensive geological study of the 1963 Vajont landslide, based on the recently performed geomechanical survey (2006-present) and on the critical analysis of the past photographic documentation (1959-1964), allows us to recognize that most GRMD evidence is related to the prehistoric multistage Mt. Toc rockslide. The 1963 catastrophic en masse remobilization induced an increase to the prehistoric damage, reworking preexisting structures and creating additional gravity-driven features (folds, fractures, faults, and rock fragmentation). The gravity-induced damage was formed during the slope instability phases that preceded the collapse (static or quasi-static GRMD) and also as a consequence of the sliding motion and of the devastating impact between the failed blocks (dynamic GRMD). Gravitational damage originated various types of small drag folds such as flexures, concentric folds, chevron, and kink-box folds, all having a radius of 1-5 m. Large buckle folds (radius of 10-50 m) are related to the dynamic damage and were formed during the en masse motion as a consequence of deceleration and impact processes that involved the sliding mass. Prior

Elbow mass flow meter

DOEpatents

McFarland, A.R.; Rodgers, J.C.; Ortiz, C.A.; Nelson, D.C.

1994-08-16

The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity. 3 figs.

Zero voltage mass spectrometry probes and systems

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

Cooks, Robert Graham; Wleklinski, Michael Stanley; Bag, Soumabha

The invention generally relates to zero volt mass spectrometry probes and systems. In certain embodiments, the invention provides a system including a mass spectrometry probe including a porous material, and a mass spectrometer (bench-top or miniature mass spectrometer). The system operates without an application of voltage to the probe. In certain embodiments, the probe is oriented such that a distal end faces an inlet of the mass spectrometer. In other embodiments, the distal end of the probe is 5 mm or less from an inlet of the mass spectrometer.

Parametric Mass Reliability Study

NASA Technical Reports Server (NTRS)

Holt, James P.

2014-01-01

The International Space Station (ISS) systems are designed based upon having redundant systems with replaceable orbital replacement units (ORUs). These ORUs are designed to be swapped out fairly quickly, but some are very large, and some are made up of many components. When an ORU fails, it is replaced on orbit with a spare; the failed unit is sometimes returned to Earth to be serviced and re-launched. Such a system is not feasible for a 500+ day long-duration mission beyond low Earth orbit. The components that make up these ORUs have mixed reliabilities. Components that make up the most mass-such as computer housings, pump casings, and the silicon board of PCBs-typically are the most reliable. Meanwhile components that tend to fail the earliest-such as seals or gaskets-typically have a small mass. To better understand the problem, my project is to create a parametric model that relates both the mass of ORUs to reliability, as well as the mass of ORU subcomponents to reliability.

Measurement and Visualization of Mass Transport for the Flowing Atmospheric Pressure Afterglow (FAPA) Ambient Mass-Spectrometry Source

PubMed Central

Pfeuffer, Kevin P.; Ray, Steven J.; Hieftje, Gary M.

2014-01-01

Ambient desorption/ionization mass spectrometry (ADI-MS) has developed into an important analytical field over the last nine years. The ability to analyze samples under ambient conditions while retaining the sensitivity and specificity of mass spectrometry has led to numerous applications and a corresponding jump in the popularity of this field. Despite the great potential of ADI-MS, problems remain in the areas of ion identification and quantification. Difficulties with ion identification can be solved through modified instrumentation, including accurate-mass or MS/MS capabilities for analyte identification. More difficult problems include quantification due to the ambient nature of the sampling process. To characterize and improve sample volatilization, ionization, and introduction into the mass-spectrometer interface, a method of visualizing mass transport into the mass spectrometer is needed. Schlieren imaging is a well-established technique that renders small changes in refractive index visible. Here, schlieren imaging was used to visualize helium flow from a plasma-based ADI-MS source into a mass spectrometer while ion signals were recorded. Optimal sample positions for melting-point capillary and transmission-mode (stainless steel mesh) introduction were found to be near (within 1 mm of) the mass spectrometer inlet. Additionally, the orientation of the sampled surface plays a significant role. More efficient mass transport resulted for analyte deposits directly facing the MS inlet. Different surfaces (glass slide and rough surface) were also examined; for both it was found that the optimal position is immediately beneath the MS inlet. PMID:24658804

Measurement and visualization of mass transport for the flowing atmospheric pressure afterglow (FAPA) ambient mass-spectrometry source.

PubMed

Pfeuffer, Kevin P; Ray, Steven J; Hieftje, Gary M

2014-05-01

Ambient desorption/ionization mass spectrometry (ADI-MS) has developed into an important analytical field over the last 9 years. The ability to analyze samples under ambient conditions while retaining the sensitivity and specificity of mass spectrometry has led to numerous applications and a corresponding jump in the popularity of this field. Despite the great potential of ADI-MS, problems remain in the areas of ion identification and quantification. Difficulties with ion identification can be solved through modified instrumentation, including accurate-mass or MS/MS capabilities for analyte identification. More difficult problems include quantification because of the ambient nature of the sampling process. To characterize and improve sample volatilization, ionization, and introduction into the mass spectrometer interface, a method of visualizing mass transport into the mass spectrometer is needed. Schlieren imaging is a well-established technique that renders small changes in refractive index visible. Here, schlieren imaging was used to visualize helium flow from a plasma-based ADI-MS source into a mass spectrometer while ion signals were recorded. Optimal sample positions for melting-point capillary and transmission-mode (stainless steel mesh) introduction were found to be near (within 1 mm of) the mass spectrometer inlet. Additionally, the orientation of the sampled surface plays a significant role. More efficient mass transport resulted for analyte deposits directly facing the MS inlet. Different surfaces (glass slide and rough surface) were also examined; for both it was found that the optimal position is immediately beneath the MS inlet.

Measurement and Visualization of Mass Transport for the Flowing Atmospheric Pressure Afterglow (FAPA) Ambient Mass-Spectrometry Source

NASA Astrophysics Data System (ADS)

Pfeuffer, Kevin P.; Ray, Steven J.; Hieftje, Gary M.

2014-05-01

Ambient desorption/ionization mass spectrometry (ADI-MS) has developed into an important analytical field over the last 9 years. The ability to analyze samples under ambient conditions while retaining the sensitivity and specificity of mass spectrometry has led to numerous applications and a corresponding jump in the popularity of this field. Despite the great potential of ADI-MS, problems remain in the areas of ion identification and quantification. Difficulties with ion identification can be solved through modified instrumentation, including accurate-mass or MS/MS capabilities for analyte identification. More difficult problems include quantification because of the ambient nature of the sampling process. To characterize and improve sample volatilization, ionization, and introduction into the mass spectrometer interface, a method of visualizing mass transport into the mass spectrometer is needed. Schlieren imaging is a well-established technique that renders small changes in refractive index visible. Here, schlieren imaging was used to visualize helium flow from a plasma-based ADI-MS source into a mass spectrometer while ion signals were recorded. Optimal sample positions for melting-point capillary and transmission-mode (stainless steel mesh) introduction were found to be near (within 1 mm of) the mass spectrometer inlet. Additionally, the orientation of the sampled surface plays a significant role. More efficient mass transport resulted for analyte deposits directly facing the MS inlet. Different surfaces (glass slide and rough surface) were also examined; for both it was found that the optimal position is immediately beneath the MS inlet.

Mass measurement errors of Fourier-transform mass spectrometry (FTMS): distribution, recalibration, and application.

PubMed

Zhang, Jiyang; Ma, Jie; Dou, Lei; Wu, Songfeng; Qian, Xiaohong; Xie, Hongwei; Zhu, Yunping; He, Fuchu

2009-02-01

The hybrid linear trap quadrupole Fourier-transform (LTQ-FT) ion cyclotron resonance mass spectrometer, an instrument with high accuracy and resolution, is widely used in the identification and quantification of peptides and proteins. However, time-dependent errors in the system may lead to deterioration of the accuracy of these instruments, negatively influencing the determination of the mass error tolerance (MET) in database searches. Here, a comprehensive discussion of LTQ/FT precursor ion mass error is provided. On the basis of an investigation of the mass error distribution, we propose an improved recalibration formula and introduce a new tool, FTDR (Fourier-transform data recalibration), that employs a graphic user interface (GUI) for automatic calibration. It was found that the calibration could adjust the mass error distribution to more closely approximate a normal distribution and reduce the standard deviation (SD). Consequently, we present a new strategy, LDSF (Large MET database search and small MET filtration), for database search MET specification and validation of database search results. As the name implies, a large-MET database search is conducted and the search results are then filtered using the statistical MET estimated from high-confidence results. By applying this strategy to a standard protein data set and a complex data set, we demonstrate the LDSF can significantly improve the sensitivity of the result validation procedure.

Identification of Unknown Contaminants in Water Samples from ISS Employing Liquid Chromatography/Mass Spectrometry/Mass Spectrometry

NASA Technical Reports Server (NTRS)

Rutz, Jeffrey A.; Schultz, John R.

2008-01-01

Mass Spectrometry/Mass Spectrometry (MS/MS) is a powerful technique for identifying unknown organic compounds. For non-volatile or thermally unstable unknowns dissolved in liquids, liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) is often the variety of MS/MS used for the identification. One type of LC/MS/MS that is rapidly becoming popular is time-of-flight (TOF) mass spectrometry. This technique is now in use at the Johnson Space Center for identification of unknown nonvolatile organics in water samples from the space program. An example of the successful identification of one unknown is reviewed in detail in this paper. The advantages of time-of-flight instrumentation are demonstrated through this example as well as the strategy employed in using time-of-flight data to identify unknowns.

Diversity in Mass Communication Theory Courses.

ERIC Educational Resources Information Center

Lasorsa, Dominic L.

2002-01-01

Shows how prominent mass communication theories can be employed to further knowledge of diversity-related issues. Provides examples of how diversity-related issues can be addressed in mass communication theory courses. Concludes that, by definition, mass communication must take into account diversity. (PM)

Measuring Transmission Efficiencies Of Mass Spectrometers

NASA Technical Reports Server (NTRS)

Srivastava, Santosh K.

1989-01-01

Coincidence counts yield absolute efficiencies. System measures mass-dependent transmission efficiencies of mass spectrometers, using coincidence-counting techniques reminiscent of those used for many years in calibration of detectors for subatomic particles. Coincidences between detected ions and electrons producing them counted during operation of mass spectrometer. Under certain assumptions regarding inelastic scattering of electrons, electron/ion-coincidence count is direct measure of transmission efficiency of spectrometer. When fully developed, system compact, portable, and used routinely to calibrate mass spectrometers.

Mass discrimination during weightlessness

NASA Technical Reports Server (NTRS)

Ross, H.

1981-01-01

An experiment concerned with the ability of astronauts to discriminate between the mass of objects when both the objects and the astronauts are in weightless states is described. The main object of the experiment is to compare the threshold for weight-discrimination on Earth with that for mass-discrimination in orbit. Tests will be conducted premission and postmission and early and late during the mission while the crew is experiencing weightlessness. A comparison of early and late tests inflight and postflight will reveal the rate of adaptation to zero-gravity and 1-g. The mass discrimination box holds 24 balls which the astronaut will compare to one another in a random routine.

Mass spectrometry of long-lived radionuclides

NASA Astrophysics Data System (ADS)

Becker, Johanna Sabine

2003-10-01

The capability of determining element concentrations at the trace and ultratrace level and isotope ratios is a main feature of inorganic mass spectrometry. The precise and accurate determination of isotope ratios of long-lived natural and artificial radionuclides is required, e.g. for their environmental monitoring and health control, for studying radionuclide migration, for age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, for quality assurance and determination of the burn-up of fuel material in a nuclear power plant, for reprocessing plants, nuclear material accounting and radioactive waste control. Inorganic mass spectrometry, especially inductively coupled plasma mass spectrometry (ICP-MS) as the most important inorganic mass spectrometric technique today, possesses excellent sensitivity, precision and good accuracy for isotope ratio measurements and practically no restriction with respect to the ionization potential of the element investigated—therefore, thermal ionization mass spectrometry (TIMS), which has been used as the dominant analytical technique for precise isotope ratio measurements of long-lived radionuclides for many decades, is being replaced increasingly by ICP-MS. In the last few years instrumental progress in improving figures of merit for the determination of isotope ratio measurements of long-lived radionuclides in ICP-MS has been achieved by the application of a multiple ion collector device (MC-ICP-MS) and the introduction of the collision cell interface in order to dissociate disturbing argon-based molecular ions, to reduce the kinetic energy of ions and neutralize the disturbing noble gas ions (e.g. of 129Xe + for the determination of 129I). The review describes the state of the art and the progress of different inorganic mass spectrometric techniques such as ICP-MS, laser ablation ICP-MS vs. TIMS, glow discharge mass spectrometry, secondary ion mass spectrometry, resonance ionization mass

Dynamic mass exchange in doubly degenerate binaries. I - 0.9 and 1.2 solar mass stars

NASA Technical Reports Server (NTRS)

Benz, W.; Cameron, A. G. W.; Press, W. H.; Bowers, R. L.

1990-01-01

The dynamic mass exchange process in doubly degenerate binaries was investigated using a three-dimensional numerical simulation of the evolution of a doubly degenerate binary system in which the primary is a 1.2-solar-mass white dwarf and the Roche lobe filling secondary is a 0.9-solar-mass dwarf. The results show that, in a little more than two orbital periods, the secondary is completely destroyed and transformed into a thick disk orbiting about the primary. Since only a very small fraction of the mass (0.0063 solar mass) escapes the system, the evolution of the binary results in the formation of a massive object. This object is composed of three parts, the initial white dwarf primary, a very hot pressure-supported spherical envelope, and a rotationally supported outer disk. The evolution of the system can be understood in terms of a simple analytical model where it is shown that the angular momentum carried by the mass during the transfer and stored in the disk determines the evolution of the system.

Mass psychogenic illness after vaccination.

PubMed

Clements, C John

2003-01-01

When vaccines are administered to groups, the physical reactions of the recipients may be similar, causing a form of mass reaction, the mechanism for which is the same as that for mass reactions from other causes. These phenomena have been categorised as mass psychogenic illness (MPI), and have been defined as the collective occurrence of a constellation of symptoms suggestive of organic illness but without an identified cause in a group of people with shared beliefs about the cause of the symptom(s). A review of the literature shows that such outbreaks have been reported in differing cultural and environmental settings including developing and industrialised countries, in the work place, on public transport, in schools, and the military. The perceived threats have been against agents such as food poisoning, fire and toxic gases. Whatever the place or perceived threat, the response seems to be similar. The symptoms generally included headache, dizziness, weakness, and loss of consciousness. Once under way, MPIs are not easy to stop. Incidents reported in the literature show that they can quickly gather momentum and can be amplified by the press who disseminate information rapidly, escalating the events. Management of such mass events can be extremely difficult. Should the public health official in charge continue to try and determine the cause, or should this person call off the entire investigation? It is suggested here that once vaccines are identified as a probable cause of the phenomenon, a dismissive approach may actually be harmful. Unless the spokesperson has already earned a high level of trust, the public are not likely to be convinced easily that nothing was wrong with the vaccine until it has been tested. An increased awareness of MPIs on the part of organisers of future mass vaccination campaigns seems appropriate. Immunisation managers should be aware that mass immunisation campaigns could generate such mass reactions. It is therefore essential that

Biological particle analysis by mass spectrometry

NASA Technical Reports Server (NTRS)

Vilker, V. L.; Platz, R. M.

1983-01-01

An instrument that analyzes the chemical composition of biological particles in aerosol or hydrosol form was developed. Efforts were directed toward the acquisition of mass spectra from aerosols of biomolecules and bacteria. The filament ion source was installed on the particle analysis by mass spectrometry system. Modifications of the vacuum system improved the sensitivity of the mass spectrometer. After the modifications were incorporated, detailed mass spectra of simple compounds from the three major classes of biomolecules, proteins, nucleic acids, and carbohydrates were obtained. A method of generating bacterial aerosols was developed. The aerosols generated were collected and examined in the scanning electron microscope to insure that the bacteria delivered to the mass spectrometer were intact and free from debris.

Mass spectrometry with accelerators.

PubMed

Litherland, A E; Zhao, X-L; Kieser, W E

2011-01-01

As one in a series of articles on Canadian contributions to mass spectrometry, this review begins with an outline of the history of accelerator mass spectrometry (AMS), noting roles played by researchers at three Canadian AMS laboratories. After a description of the unique features of AMS, three examples, (14)C, (10)Be, and (129)I are given to illustrate the methods. The capabilities of mass spectrometry have been extended by the addition of atomic isobar selection, molecular isobar attenuation, further ion acceleration, followed by ion detection and ion identification at essentially zero dark current or ion flux. This has been accomplished by exploiting the techniques and accelerators of atomic and nuclear physics. In 1939, the first principles of AMS were established using a cyclotron. In 1977 the selection of isobars in the ion source was established when it was shown that the (14)N(-) ion was very unstable, or extremely difficult to create, making a tandem electrostatic accelerator highly suitable for assisting the mass spectrometric measurement of the rare long-lived radioactive isotope (14)C in the environment. This observation, together with the large attenuation of the molecular isobars (13)CH(-) and (12)CH 2(-) during tandem acceleration and the observed very low background contamination from the ion source, was found to facilitate the mass spectrometry of (14)C to at least a level of (14)C/C ~ 6 × 10(-16), the equivalent of a radiocarbon age of 60,000 years. Tandem Accelerator Mass Spectrometry, or AMS, has now made possible the accurate radiocarbon dating of milligram-sized carbon samples by ion counting as well as dating and tracing with many other long-lived radioactive isotopes such as (10)Be, (26)Al, (36)Cl, and (129)I. The difficulty of obtaining large anion currents with low electron affinities and the difficulties of isobar separation, especially for the heavier mass ions, has prompted the use of molecular anions and the search for alternative

High mass resolution time of flight mass spectrometer for measuring products in heterogeneous catalysis in highly sensitive microreactors

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

Andersen, T.; Jensen, R.; Christensen, M. K.

2012-07-15

We demonstrate a combined microreactor and time of flight system for testing and characterization of heterogeneous catalysts with high resolution mass spectrometry and high sensitivity. Catalyst testing is performed in silicon-based microreactors which have high sensitivity and fast thermal response. Gas analysis is performed with a time of flight mass spectrometer with a modified nude Bayard-Alpert ionization gauge as gas ionization source. The mass resolution of the time of flight mass spectrometer using the ion gauge as ionization source is estimated to m/{Delta}m > 2500. The system design is superior to conventional batch and flow reactors with accompanying product detectionmore » by quadrupole mass spectrometry or gas chromatography not only due to the high sensitivity, fast temperature response, high mass resolution, and fast acquisition time of mass spectra but it also allows wide mass range (0-5000 amu in the current configuration). As a demonstration of the system performance we present data from ammonia oxidation on a Pt thin film showing resolved spectra of OH and NH{sub 3}.« less

High mass resolution time of flight mass spectrometer for measuring products in heterogeneous catalysis in highly sensitive microreactors

NASA Astrophysics Data System (ADS)

Andersen, T.; Jensen, R.; Christensen, M. K.; Pedersen, T.; Hansen, O.; Chorkendorff, I.

2012-07-01

We demonstrate a combined microreactor and time of flight system for testing and characterization of heterogeneous catalysts with high resolution mass spectrometry and high sensitivity. Catalyst testing is performed in silicon-based microreactors which have high sensitivity and fast thermal response. Gas analysis is performed with a time of flight mass spectrometer with a modified nude Bayard-Alpert ionization gauge as gas ionization source. The mass resolution of the time of flight mass spectrometer using the ion gauge as ionization source is estimated to m/Δm > 2500. The system design is superior to conventional batch and flow reactors with accompanying product detection by quadrupole mass spectrometry or gas chromatography not only due to the high sensitivity, fast temperature response, high mass resolution, and fast acquisition time of mass spectra but it also allows wide mass range (0-5000 amu in the current configuration). As a demonstration of the system performance we present data from ammonia oxidation on a Pt thin film showing resolved spectra of OH and NH3.

High mass resolution time of flight mass spectrometer for measuring products in heterogeneous catalysis in highly sensitive microreactors.

PubMed

Andersen, T; Jensen, R; Christensen, M K; Pedersen, T; Hansen, O; Chorkendorff, I

2012-07-01

We demonstrate a combined microreactor and time of flight system for testing and characterization of heterogeneous catalysts with high resolution mass spectrometry and high sensitivity. Catalyst testing is performed in silicon-based microreactors which have high sensitivity and fast thermal response. Gas analysis is performed with a time of flight mass spectrometer with a modified nude Bayard-Alpert ionization gauge as gas ionization source. The mass resolution of the time of flight mass spectrometer using the ion gauge as ionization source is estimated to m/Δm > 2500. The system design is superior to conventional batch and flow reactors with accompanying product detection by quadrupole mass spectrometry or gas chromatography not only due to the high sensitivity, fast temperature response, high mass resolution, and fast acquisition time of mass spectra but it also allows wide mass range (0-5000 amu in the current configuration). As a demonstration of the system performance we present data from ammonia oxidation on a Pt thin film showing resolved spectra of OH and NH(3).

Fermion masses in SO(10)

NASA Astrophysics Data System (ADS)

Jungman, Gerard

1992-11-01

Yukawa-coupling-constant unification together with the known fermion masses is used to constrain SO(10) models. We consider the case of one (heavy) generation, with the tree-level relation mb=mτ, calculating the limits on the intermediate scales due to the known limits on fermion masses. This analysis extends previous analyses which addressed only the simplest symmetry-breaking schemes. In the case where the low-energy model is the standard model with one Higgs doublet, there are very strong constraints due to the known limits on the top-quark mass and the τ-neutrino mass. The two-Higgs-doublet case is less constrained, though we can make progress in constraining this model also. We identify those parameters to which the viability of the model is most sensitive. We also discuss the ``triviality'' bounds on mt obtained from the analysis of the Yukawa renormalization-group equations. Finally we address the role of a speculative constraint on the τ-neutrino mass, arising from the cosmological implications of anomalous B+L violation in the early Universe.

Highly multiparametric analysis by mass cytometry.

PubMed

Ornatsky, Olga; Bandura, Dmitry; Baranov, Vladimir; Nitz, Mark; Winnik, Mitchell A; Tanner, Scott

2010-09-30

This review paper describes a new technology, mass cytometry, that addresses applications typically run by flow cytometer analyzers, but extends the capability to highly multiparametric analysis. The detection technology is based on atomic mass spectrometry. It offers quantitation, specificity and dynamic range of mass spectrometry in a format that is familiar to flow cytometry practitioners. The mass cytometer does not require compensation, allowing the application of statistical techniques; this has been impossible given the constraints of fluorescence noise with traditional cytometry instruments. Instead of "colors" the mass cytometer "reads" the stable isotope tags attached to antibodies using metal-chelating labeling reagents. Because there are many available stable isotopes, and the mass spectrometer provides exquisite resolution between detection channels, many parameters can be measured as easily as one. For example, in a single tube the technique allows for the ready detection and characterization of the major cell subsets in blood or bone marrow. Here we describe mass cytometric immunophenotyping of human leukemia cell lines and leukemia patient samples, differential cell analysis of normal peripheral and umbilical cord blood; intracellular protein identification and metal-encoded bead arrays. Copyright © 2010 Elsevier B.V. All rights reserved.

Genetic Factors in Determining Bone Mass

PubMed Central

Smith, David M.; Nance, Walter E.; Kang, Ke Won; Christian, Joe C.; Johnston, C. Conrad

1973-01-01

This investigation was undertaken to evaluate possible genetic determinants of bone mass with the premise that inheritance of bone mass could be of etiologic importance in osteoporosis. Bone mass and width measurements were made with the photon absorption technique on the right radius of 71 juvenile and 80 adult twin paris. The variance of intrapair differences of bone mass in monozygotic (MZ) juvenile twins was 0.0013 g2/cm2 compared to 0.0052 g2/cm2 in the dizygotic (DZ) twins. For the adult twins the variance of intrapair differences in bone mass was 0.0069 for MZ and 0.0137 for DZ twins. Similar results were obtained for bone width. The significantly larger variation in intrapair differences in DZ twins indicates that these traits have significant genetic determinants. These intrapair differences were found to increase with age, suggesting that genetic-environmental interaction also contributes to the observed variation in bone mass. These data provide evidence that bone mass does have significant genetic factors, which alone or in conjunction with environmental factors may predispose persons to the development of osteoporosis. PMID:4795916

The chemical composition and mineralogy of meteorites measured with very high spatial resolution by a laser mass spectrometer for in situ planetary research

NASA Astrophysics Data System (ADS)

Brigitte Neuland, Maike; Mezger, Klaus; Tulej, Marek; Frey, Samira; Riedo, Andreas; Wurz, Peter; Wiesendanger, Reto

2017-04-01

asteroid. [1] Wurz, P., Whitby, J., Managadze, G. , "Laser Mass Spectrometry in Planetary Science", AIP Conf.Proc. CP1144(2009): 70-75. [2] Rohner, U., Whitby, J.A. and Wurz, P. "A miniature laser ablation time-of-flight mass spectrometer for in situ planetary exploration", Measurement Science and Technology 14 (2003): 2159-2164. [3] Riedo, A., Bieler, A., Neuland, M., Tulej, M. and Wurz, P., "Performance evaluation of a miniature laser ablation time-of-flight mass spectrometer designed for in situ investigations in planetary space research", Journal of Mass Spectrometry 48 (2013): 1 -15 [4] Neuland, M.B., Grimaudo, V., Mezger, K., Moreno-García, P., Riedo, A., Tulej, M. and Wurz, P., "Quantitative measurement of the chemical composition of geological standards with a miniature laser ablation/ionisation mass spectrometer designed for in situ application in space research", Meas. Sci. Technol. 27(2016), article ID:035904, 1 - 13. [5] Tulej, M., Neubeck, A., Ivarsson, M., Riedo, A., Neuland, M.B., Meyer, S. and Wurz, P., "Chemical composition of micrometer-sized filaments in an aragonite host by a miniature laser ablation/ionization mass spectrometer", Astrobiol., 15 (2015): 669 - 682.

Body Mass Measurement - Skylab Experiment M172

NASA Technical Reports Server (NTRS)

1972-01-01

This chart provides details on Skylab's Body Mass Measurement experiment (M172). The M172 experiment was a medical study to determine the body mass of each crew member and observe changes in body masses during flight. Knowledge of exact body mass variations throughout the flight aided significantly in the correlation of other medical data obtained during the flight. Mass measurements under zero-gravity conditions were achieved by the application of Newton's second law (force equals mass times acceleration). The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

Convex-hull mass estimates of the dodo (Raphus cucullatus): application of a CT-based mass estimation technique

PubMed Central

O’Mahoney, Thomas G.; Kitchener, Andrew C.; Manning, Phillip L.; Sellers, William I.

2016-01-01

The external appearance of the dodo (Raphus cucullatus, Linnaeus, 1758) has been a source of considerable intrigue, as contemporaneous accounts or depictions are rare. The body mass of the dodo has been particularly contentious, with the flightless pigeon alternatively reconstructed as slim or fat depending upon the skeletal metric used as the basis for mass prediction. Resolving this dichotomy and obtaining a reliable estimate for mass is essential before future analyses regarding dodo life history, physiology or biomechanics can be conducted. Previous mass estimates of the dodo have relied upon predictive equations based upon hind limb dimensions of extant pigeons. Yet the hind limb proportions of dodo have been found to differ considerably from those of their modern relatives, particularly with regards to midshaft diameter. Therefore, application of predictive equations to unusually robust fossil skeletal elements may bias mass estimates. We present a whole-body computed tomography (CT) -based mass estimation technique for application to the dodo. We generate 3D volumetric renders of the articulated skeletons of 20 species of extant pigeons, and wrap minimum-fit ‘convex hulls’ around their bony extremities. Convex hull volume is subsequently regressed against mass to generate predictive models based upon whole skeletons. Our best-performing predictive model is characterized by high correlation coefficients and low mean squared error (a = − 2.31, b = 0.90, r2 = 0.97, MSE = 0.0046). When applied to articulated composite skeletons of the dodo (National Museums Scotland, NMS.Z.1993.13; Natural History Museum, NHMUK A.9040 and S/1988.50.1), we estimate eviscerated body masses of 8–10.8 kg. When accounting for missing soft tissues, this may equate to live masses of 10.6–14.3 kg. Mass predictions presented here overlap at the lower end of those previously published, and support recent suggestions of a relatively slim dodo. CT-based reconstructions provide a

Physiological and Proteomic Analysis of the Rice Mutant cpm2 Suggests a Negative Regulatory Role of Jasmonic Acid in Drought Tolerance

PubMed Central

Dhakarey, Rohit; Raorane, Manish L.; Treumann, Achim; Peethambaran, Preshobha K.; Schendel, Rachel R.; Sahi, Vaidurya P.; Hause, Bettina; Bunzel, Mirko; Henry, Amelia; Kohli, Ajay; Riemann, Michael

2017-01-01

It is widely known that numerous adaptive responses of drought-stressed plants are stimulated by chemical messengers known as phytohormones. Jasmonic acid (JA) is one such phytohormone. But there are very few reports revealing its direct implication in drought related responses or its cross-talk with other phytohormones. In this study, we compared the morpho-physiological traits and the root proteome of a wild type (WT) rice plant with its JA biosynthesis mutant coleoptile photomorphogenesis 2 (cpm2), disrupted in the allene oxide cyclase (AOC) gene, for insights into the role of JA under drought. The mutant had higher stomatal conductance, higher water use efficiency and higher shoot ABA levels under severe drought as compared to the WT. Notably, roots of cpm2 were better developed compared to the WT under both, control and drought stress conditions. Root proteome was analyzed using the Tandem Mass Tag strategy to better understand this difference at the molecular level. Expectedly, AOC was unique but notably highly abundant under drought in the WT. Identification of other differentially abundant proteins (DAPs) suggested increased energy metabolism (i.e., increased mobilization of resources) and reactive oxygen species scavenging in cpm2 under drought. Additionally, various proteins involved in secondary metabolism, cell growth and cell wall synthesis were also more abundant in cpm2 roots. Proteome-guided transcript, metabolite, and histological analyses provided further insights into the favorable adaptations and responses, most likely orchestrated by the lack of JA, in the cpm2 roots. Our results in cpm2 are discussed in the light of JA crosstalk to other phytohormones. These results together pave the path for understanding the precise role of JA during drought stress in rice. PMID:29250082

14 CFR 23.659 - Mass balance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Mass balance. 23.659 Section 23.659 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Surfaces § 23.659 Mass balance. The supporting structure and the attachment of concentrated mass balance...

14 CFR 23.659 - Mass balance.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Mass balance. 23.659 Section 23.659 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Surfaces § 23.659 Mass balance. The supporting structure and the attachment of concentrated mass balance...

Effective vortex mass from microscopic theory

NASA Astrophysics Data System (ADS)

Han, Jung Hoon; Kim, June Seo; Kim, Min Jae; Ao, Ping

2005-03-01

We calculate the effective mass of a single quantized vortex in the Bardeen-Cooper-Schrieffer superconductor at finite temperature. Based on effective action approach, we arrive at the effective mass of a vortex as integral of the spectral function J(ω) divided by ω3 over frequency. The spectral function is given in terms of the quantum-mechanical transition elements of the gradient of the Hamiltonian between two Bogoliubov-deGennes (BdG) eigenstates. Based on self-consistent numerical diagonalization of the BdG equation we find that the effective mass per unit length of vortex at zero temperature is of order m(kfξ0)2 ( kf=Fermi momentum, ξ0=coherence length), essentially equaling the electron mass displaced within the coherence length from the vortex core. Transitions between the core states are responsible for most of the mass. The mass reaches a maximum value at T≈0.5Tc and decreases continuously to zero at Tc .

Evolution of Orbitrap Mass Spectrometry Instrumentation

NASA Astrophysics Data System (ADS)

Eliuk, Shannon; Makarov, Alexander

2015-07-01

We discuss the evolution of OrbitrapTM mass spectrometry (MS) from its birth in the late 1990s to its current role as one of the most prominent techniques for MS. The Orbitrap mass analyzer is the first high-performance mass analyzer that employs trapping of ions in electrostatic fields. Tight integration with the ion injection process enables the high-resolution, mass accuracy, and sensitivity that have become essential for addressing analytical needs in numerous areas of research, as well as in routine analysis. We examine three major families of instruments (related to the LTQ Orbitrap, Q Exactive, and Orbitrap Fusion mass spectrometers) in the context of their historical development over the past ten eventful years. We discuss as well future trends and perspectives of Orbitrap MS. We illustrate the compelling potential of Orbitrap-based mass spectrometers as (ultra) high-resolution platforms, not only for high-end proteomic applications, but also for routine targeted analysis.

Mass Loss during Late Stellar Evolution

NASA Astrophysics Data System (ADS)

Olofsson, Hans

1999-10-01

Extensive post-main sequence mass loss occurs for low- and intermediate-mass (up to ~8MSun) stars on the asymptotic giant branch (AGB), and for the higher-mass stars during their red supergiant evolution. These winds have a profound effect on the evolution of the stars, as well as for the enrichment of the interstellar medium with heavy elements and grain particles. The mass loss on the AGB is the by far most well studied, but a good deal of the basic processes are still not understood or cannot be described in a proper quantitative way, e.g., the mass loss mechanism itself. Furthermore, these objects provide us with fascinating systems, where intricate interplays between various physical and chemical processes take place, and their relative simplicity in terms of geometry, density distribution, and kinematics makes them excellent astrophysical laboratories. In this review we will concentrate on those aspects of AGB mass loss that are particularly well studied using a large millimetre array.

The BDNYC database of low-mass stars, brown dwarfs, and planetary mass companions

NASA Astrophysics Data System (ADS)

Cruz, Kelle; Rodriguez, David; Filippazzo, Joseph; Gonzales, Eileen; Faherty, Jacqueline K.; Rice, Emily; BDNYC

2018-01-01

We present a web-interface to a database of low-mass stars, brown dwarfs, and planetary mass companions. Users can send SELECT SQL queries to the database, perform searches by coordinates or name, check the database inventory on specified objects, and even plot spectra interactively. The initial version of this database contains information for 198 objects and version 2 will contain over 1000 objects. The database currently includes photometric data from 2MASS, WISE, and Spitzer and version 2 will include a significant portion of the publicly available optical and NIR spectra for brown dwarfs. The database is maintained and curated by the BDNYC research group and we welcome contributions from other researchers via GitHub.

Characterisation of an ion source on the Helix MC Plus noble gas mass spectrometer - pressure dependent mass discrimination

NASA Astrophysics Data System (ADS)

Zhang, X.

2017-12-01

Characterisation of an ion source on the Helix MC Plusnoble gas mass spectrometer - pressure dependent mass discrimination Xiaodong Zhang* dong.zhang@anu.edu.au Masahiko Honda Masahiko.honda@anu.edu.au Research School of Earth Sciences, The Australian National University, Canberra, Australia To obtain reliable measurements of noble gas elemental and isotopic abundances in a geological sample it is essential that the mass discrimination (instrument-induced isotope fractionation) of the mass spectrometer remain constant over the working range of noble gas partial pressures. It is known, however, that there are pressure-dependent variations in sensitivity and mass discrimination in conventional noble gas mass spectrometers [1, 2, 3]. In this study, we discuss a practical approach to ensuring that the pressure effect in the Helix MC Plus high resolution, multi-collector noble gas mass spectrometer is minimised. The isotopic composition of atmospheric Ar was measured under a range of operating conditions to test the effects of different parameters on Ar mass discrimination. It was found that the optimised ion source conditions for pressure independent mass discrimination for Ar were different from those for maximised Ar sensitivity. The optimisation can be achieved by mainly adjusting the repeller voltage. It is likely that different ion source settings will be required to minimise pressure-dependent mass discrimination for different noble gases. A recommended procedure for tuning an ion source to reduce pressure dependent mass discrimination will be presented. References: Honda M., et al., Geochim. Cosmochim. Acta, 57, 859 -874, 1993. Burnard P. G., and Farley K. A., Geochemistry Geophysics Geosystems, Volume 1, 2000GC00038, 2000. Mabry J., et al., Journal of Analytical Atomic Spectrometry, 27, 1012 - 1017, 2012.

Nonuniversal gaugino masses and muon g - 2

DOE PAGES

Gogoladze, Ilia; Nasir, Fariha; Shafi, Qaisar; ...

2014-08-11

We consider two classes of supersymmetric models with nonuniversal gaugino masses at the grand unification scale M GUT in an attempt to resolve the apparent muon g-2 anomaly encountered in the Standard Model. We explore two distinct scenarios, one in which all gaugino masses have the same sign at M GUT, and a second case with opposite sign gaugino masses. The sfermion masses in both cases are assumed to be universal at M GUT. We exploit the nonuniversality among gaugino masses to realize large mass splitting between the colored and noncolored sfermions. Thus, the sleptons can have masses in themore » few hundred GeV range, whereas the colored sparticles turn out to be an order of magnitude or so heavier. In both models the resolution of the muon g-2 anomaly is compatible, among other things, with a 125–126 GeV Higgs boson mass and the WMAP dark matter bounds.« less

Precision mass measurements of magnesium isotopes and implications for the validity of the isobaric mass multiplet equation

DOE PAGES

Brodeur, M.; Kwiatkowski, A. A.; Drozdowski, O. M.; ...

2017-09-18

If the mass excess of neutron-deficient nuclei and their neutron-rich mirror partners are both known, it can be shown that deviations of the isobaric mass multiplet equation (IMME) in the form of a cubic term can be probed. Such a cubic term was probed by using the atomic mass of neutron-rich magnesium isotopes measured using the TITAN Penning trap and the recently measured proton-separation energies of 29Cl and 30Ar. The atomic mass of 27Mg was found to be within 1.6σ of the value stated in the Atomic Mass Evaluation. The atomic masses of 28,29Mg were measured to be both withinmore » 1σ, while being 7 and 33 times more precise, respectively. Using the 29Mg mass excess and previous measurements of 29Cl, we uncovered a cubic coefficient of d = 28(7)keV, which is the largest known cubic coefficient of the IMME. This departure, however, could also be caused by experimental data with unknown systematic errors. Hence there is a need to confirm the mass excess of 28S and the one-neutron separation energy of 29Cl, which have both come from a single measurement. Lastly, our results were compared with ab initio calculations from the valence-space in-medium similarity renormalization group, resulting in a good agreement.« less

Precision mass measurements of magnesium isotopes and implications for the validity of the isobaric mass multiplet equation

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

Brodeur, M.; Kwiatkowski, A. A.; Drozdowski, O. M.

If the mass excess of neutron-deficient nuclei and their neutron-rich mirror partners are both known, it can be shown that deviations of the isobaric mass multiplet equation (IMME) in the form of a cubic term can be probed. Such a cubic term was probed by using the atomic mass of neutron-rich magnesium isotopes measured using the TITAN Penning trap and the recently measured proton-separation energies of 29Cl and 30Ar. The atomic mass of 27Mg was found to be within 1.6σ of the value stated in the Atomic Mass Evaluation. The atomic masses of 28,29Mg were measured to be both withinmore » 1σ, while being 7 and 33 times more precise, respectively. Using the 29Mg mass excess and previous measurements of 29Cl, we uncovered a cubic coefficient of d = 28(7)keV, which is the largest known cubic coefficient of the IMME. This departure, however, could also be caused by experimental data with unknown systematic errors. Hence there is a need to confirm the mass excess of 28S and the one-neutron separation energy of 29Cl, which have both come from a single measurement. Lastly, our results were compared with ab initio calculations from the valence-space in-medium similarity renormalization group, resulting in a good agreement.« less

Low-Mass Star Formation and the Initial Mass Function in Young Clusters

NASA Astrophysics Data System (ADS)

Luhman, Kevin Lee

I have used optical and near-infrared spectroscopy and imaging to measure spectral types and luminosities for young (/tau<10 Myr), embedded (AV=0[-]50), low-mass (0.1-1 Msolar) stars in three nearby (d<300 pc) clusters: L1495E, IC 348, and ρ Ophiuchi. In conjunction with theoretical evolutionary tracks, I have derived the star formation history and initial mass function for each stellar population. A large number of brown dwarf candidates have been identified in the photometry, several of which are confirmed through spectroscopy. Finally, I have measured the frequency and survival times of circumstellar disks and investigated the photometric and spectroscopic properties of protostars. In S 2, I apply observational tests to the available sets of evolutionary models for low-mass stars, concluding that the calculations of D'Antona & Mazzitelli are preferred for the range of masses and ages considered here. In S 3 and S 4, I examine in detail the spectroscopic characteristics and substellar nature of two brown dwarf candidates. The study then expands to include the populations within the clusters L1495E (S 5), IC 348 (S 6), and ρ Ophiuchi (S 7). In S 8, I briefly discuss the past, present, and future of scientific research related to this thesis.

Mass balancing of hollow fan blades

NASA Technical Reports Server (NTRS)

Kielb, R. E.

1986-01-01

A typical section model is used to analytically investigate the effect of mass balancing as applied to hollow, supersonic fan blades. A procedure to determine the best configuration of an internal balancing mass to provide flutter alleviation is developed. This procedure is applied to a typical supersonic shroudless fan blade which is unstable in both the solid configuration and when it is hollow with no balancing mass. The addition of an optimized balancing mass is shown to stabilize the blade at the design condition.

Vacuum Technology Considerations For Mass Metrology

PubMed Central

Abbott, Patrick J.; Jabour, Zeina J.

2011-01-01

Vacuum weighing of mass artifacts eliminates the necessity of air buoyancy correction and its contribution to the measurement uncertainty. Vacuum weighing is also an important process in the experiments currently underway for the redefinition of the SI mass unit, the kilogram. Creating the optimum vacuum environment for mass metrology requires careful design and selection of construction materials, plumbing components, pumping, and pressure gauging technologies. We review the vacuum technology1 required for mass metrology and suggest procedures and hardware for successful and reproducible operation. PMID:26989593

The Origins of Mass

ScienceCinema

Lincoln, Don

2018-01-16

The Higgs boson was discovered in July of 2012 and is generally understood to be the origin of mass. While those statements are true, they are incomplete. It turns out that the Higgs boson is responsible for only about 2% of the mass of ordinary matter. In this dramatic new video, Dr. Don Lincoln of Fermilab tells us the rest of the story.

Calculate the Top Quark Mass

Science.gov Websites

Searching for Top How do today's scientists use conservation of momentum? Particle physicists mass into energy and then energy into mass! You can use the principle of conservation of momentum which

Body Mass Index

PubMed Central

Nuttall, Frank Q.

2015-01-01

The body mass index (BMI) is the metric currently in use for defining anthropometric height/weight characteristics in adults and for classifying (categorizing) them into groups. The common interpretation is that it represents an index of an individual’s fatness. It also is widely used as a risk factor for the development of or the prevalence of several health issues. In addition, it is widely used in determining public health policies.The BMI has been useful in population-based studies by virtue of its wide acceptance in defining specific categories of body mass as a health issue. However, it is increasingly clear that BMI is a rather poor indicator of percent of body fat. Importantly, the BMI also does not capture information on the mass of fat in different body sites. The latter is related not only to untoward health issues but to social issues as well. Lastly, current evidence indicates there is a wide range of BMIs over which mortality risk is modest, and this is age related. All of these issues are discussed in this brief review. PMID:27340299

14 CFR 29.659 - Mass balance.

Code of Federal Regulations, 2014 CFR

2014-01-01

... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.659 Mass balance. (a) The rotor and blades must be mass balanced as necessary to— (1) Prevent excessive vibration; and (2) Prevent... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Mass balance. 29.659 Section 29.659...

14 CFR 27.659 - Mass balance.

Code of Federal Regulations, 2014 CFR

2014-01-01

... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.659 Mass balance. (a) The rotors and blades must be mass balanced as necessary to— (1) Prevent excessive vibration; and (2) Prevent... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Mass balance. 27.659 Section 27.659...

14 CFR 29.659 - Mass balance.

Code of Federal Regulations, 2012 CFR

2012-01-01

... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.659 Mass balance. (a) The rotor and blades must be mass balanced as necessary to— (1) Prevent excessive vibration; and (2) Prevent... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Mass balance. 29.659 Section 29.659...

14 CFR 27.659 - Mass balance.

Code of Federal Regulations, 2013 CFR

2013-01-01

... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.659 Mass balance. (a) The rotors and blades must be mass balanced as necessary to— (1) Prevent excessive vibration; and (2) Prevent... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Mass balance. 27.659 Section 27.659...

14 CFR 27.659 - Mass balance.

Code of Federal Regulations, 2012 CFR

2012-01-01

... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.659 Mass balance. (a) The rotors and blades must be mass balanced as necessary to— (1) Prevent excessive vibration; and (2) Prevent... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Mass balance. 27.659 Section 27.659...

14 CFR 29.659 - Mass balance.

Code of Federal Regulations, 2013 CFR

2013-01-01

... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.659 Mass balance. (a) The rotor and blades must be mass balanced as necessary to— (1) Prevent excessive vibration; and (2) Prevent... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Mass balance. 29.659 Section 29.659...

A NEW MASS SPECTROMETRIC TECHNIQUE FOR ...

EPA Pesticide Factsheets

Most organic compounds are not found in mass spectral libraries and cannot be easily identified from low resolution mass spectra. Ion Composition Elucidation (ICE) utilizes selected ion recording with a double focusing mass spectrometer in a new way to determine exact masses and relative abundances of ions more rapidly and with greater accuracy than by full scanning. These measurements are made as analytes from a complex mixture elute from a GC column into the ion source. The exact masses and relative abundances establish the elemental compositions of the ions in a mass spectrum, which limits the possible identify of the compound sufficiently to make searches of the chemical and commercial literature feasible. ICE has two facets: Mass Peak Profiling from Selected Ion Recording Data (MPPSIRD) for data acquisition and a Profile Generation Model (PGM) for automated data interpretation. NTPSIRD and the PGM will be described and several applications of ICE will be shown: tentative identification of a compound that provided a mass spectrum with I I plausible NIST library matches; confirmation of the presence of temazepam, a sedative and one of the 200 most prescribed drugs in 1999. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this T

Mass-losing red giants in open clusters

NASA Technical Reports Server (NTRS)

Jura, M.

1987-01-01

Mass-losing stars in open clusters with main-sequence turn-offs at intermediate mass have been searched for by using the IRAS data base. The absence of many strong 60 micron sources in open clusters implies that intermediate-mass stars lose much of their mass during an intense wind phase of rather short duration. For stars of about seven solar masses, this phase, if it exists at all, lasts for not much more than 100,000 yr. For stars of about four solar masses, the intense wind phase appears to last considerably less than 10 million yr; it may well last for less than a million yr.

Hybrid quadrupole mass filter/quadrupole ion trap/time-of-flight-mass spectrometer for infrared multiple photon dissociation spectroscopy of mass-selected ions

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

Gulyuz, Kerim; Stedwell, Corey N.; Wang Da

2011-05-15

We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photon dissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources, an electrospray ionization source, as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection, a reduced pressure ({approx}10{sup -5} Torr) quadrupole ion trap (QIT) for OPO irradiation, and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarilymore » increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay, the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study, we implemented this setup in the study of protonated tryptophan, TrpH{sup +}, as well as collision-induced dissociation products of this protonated amino acid [W. K. Mino, Jr., K. Gulyuz, D. Wang, C. N. Stedwell, and N. C. Polfer, J. Phys. Chem. Lett. 2, 299 (2011)]. Here, we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.« less

ELEMENT MASSES IN THE CRAB NEBULA

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

Sibley, Adam R.; Katz, Andrea M.; Satterfield, Timothy J.

Using our previously published element abundance or mass-fraction distributions in the Crab Nebula, we derived actual mass distributions and estimates for overall nebular masses of hydrogen, helium, carbon, nitrogen, oxygen and sulfur. As with the previous work, computations were carried out for photoionization models involving constant hydrogen density and also constant nuclear density. In addition, employing new flux measurements for [Ni ii]  λ 7378, along with combined photoionization models and analytic computations, a nickel abundance distribution was mapped and a nebular stable nickel mass estimate was derived.

Mass spectrometry and renal calculi

PubMed Central

Purcarea, VL; Sisu, I; Sisu, E

2010-01-01

The present review represents a concise and complete survey of the literature covering 2004–2009, concerning the mass spectrometric techniques involved in the structural investigation of renal calculi. After a short presentation of the fundamental mass spectrometric techniques (MALDI–TOF, QTOF, MS–MS) as well as hyphenated methods (GC–MS, LC–MS, CE–MS), an extensive study of the urinary proteome analysis as well as the detection and quantification by mass spectrometry of toxins, drugs and metabolites from renal calculi is presented. PMID:20968197

Disk mass determination through CO isotopologues

NASA Astrophysics Data System (ADS)

Miotello, Anna; Kama, Mihkel; van Dishoeck, Ewine

2015-08-01

One of the key properties for understanding how disks evolve to planetary systems is their overall mass, combined with their surface density distribution. So far, virtually all disk mass determinations are based on observations of the millimeter continuum dust emission.To derive the total gas + dust disk mass from these data involves however several big assumptions. The alternative method is to directly derive the gas mass through the detection of carbon monoxide (CO) and its less abundant isotopologues. CO chemistry is well studied and easily implemented in chemical models, provided that isotope-selective processes are properly accounted for.CO isotope-selective photodissociation was implemented for the first time in a full physical-chemical code in Miotello et al. (2014). The main result is that if isotope-selective effects are not considered in the data analysis, disk masses can be underestimated by an order of magnitude or more. For example, the mass discrepancy found for the renowned TW Hya disk may be explained or at least mitigated by this implementation. In this poster, we present new results for a large grid of disk models. We derive mass correction factors for different disk, stellar and grain properties in order to account for isotope-selective effects in analyzing ALMA data of CO isotopologues (Miotello et al., in prep.).

14 CFR 29.659 - Mass balance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Mass balance. 29.659 Section 29.659... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.659 Mass balance. (a) The rotor... flutter at any speed up to the maximum forward speed. (b) The structural integrity of the mass balance...

14 CFR 27.659 - Mass balance.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Mass balance. 27.659 Section 27.659... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.659 Mass balance. (a) The rotors... flutter at any speed up to the maximum forward speed. (b) The structural integrity of the mass balance...

14 CFR 27.659 - Mass balance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Mass balance. 27.659 Section 27.659... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.659 Mass balance. (a) The rotors... flutter at any speed up to the maximum forward speed. (b) The structural integrity of the mass balance...

14 CFR 29.659 - Mass balance.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Mass balance. 29.659 Section 29.659... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.659 Mass balance. (a) The rotor... flutter at any speed up to the maximum forward speed. (b) The structural integrity of the mass balance...

Determination of effective thoracic mass.

DOT National Transportation Integrated Search

1996-02-01

Effective thoracic mass is a critical parameter in specifying mathematical and mechanical models (such as crash dummies) of humans exposed to impact conditions. A method is developed using a numerical optimizer to determine effective thoracic mass (a...

Mass and Charge Measurements on Heavy Ions

PubMed Central

Sugai, Toshiki

2017-01-01

The relationship between mass and charge has been a crucial topic in mass spectrometry (MS) because the mass itself is typically evaluated based on the m/z ratio. Despite the fact that this measurement is indirect, a precise mass can be obtained from the m/z value with a high m/z resolution up to 105 for samples in the low mass and low charge region under 10,000 Da and 20 e, respectively. However, the target of MS has recently been expanded to the very heavy region of Mega or Giga Da, which includes large particles and biocomplexes, with very large and widely distributed charge from kilo to Mega range. In this region, it is necessary to evaluate charge and mass simultaneously. Recent studies for simultaneous mass and charge observation and related phenomena are discussed in this review. PMID:29302406

Iodine-Containing Mass-Defect-Tuned Dendrimers for Use as Internal Mass Spectrometry Calibrants

NASA Astrophysics Data System (ADS)

Giesen, Joseph A.; Diament, Benjamin J.; Grayson, Scott M.

2018-03-01

Calibrants based on synthetic dendrimers have been recently proposed as a versatile alternative to peptides and proteins for both MALDI and ESI mass spectrometry calibration. Because of their modular synthetic platform, dendrimer calibrants are particularly amenable to tailoring for specific applications. Utilizing this versatility, a set of dendrimers has been designed as an internal calibrant with a tailored mass defect to differentiate them from the majority of natural peptide analytes. This was achieved by incorporating a tris-iodinated aromatic core as an initiator for the dendrimer synthesis, thereby affording multiple calibration points ( m/z range 600-2300) with an optimized mass-defect offset relative to all peptides composed of the 20 most common proteinogenic amino acids. [Figure not available: see fulltext.

Ballistics/mass properties

NASA Technical Reports Server (NTRS)

Drendel, Albert S.; Richards, M. C.

1989-01-01

The propulsion performance and reconstructed mass properties data from Morton Thiokol's RSRM-4 motors, which were assigned to the STS-30R launch, are presented. The composite type solid propellant burn rates were close to predicted. The performance of the pair of motors were compared to some CEI Specification CPW1-3600 for compliance. Some aspects of the CEI Specification could not be compared because of low sampling of data. The performance of the motors were well within the CEI specification requirements. Post flight reconstructured RSRM mass properties are within expected values for the RSRM quarterweight and halfweight configurations.

The ATLAS3D project - XX. Mass-size and mass-σ distributions of early-type galaxies: bulge fraction drives kinematics, mass-to-light ratio, molecular gas fraction and stellar initial mass function

NASA Astrophysics Data System (ADS)

Cappellari, Michele; McDermid, Richard M.; Alatalo, Katherine; Blitz, Leo; Bois, Maxime; Bournaud, Frédéric; Bureau, M.; Crocker, Alison F.; Davies, Roger L.; Davis, Timothy A.; de Zeeuw, P. T.; Duc, Pierre-Alain; Emsellem, Eric; Khochfar, Sadegh; Krajnović, Davor; Kuntschner, Harald; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Sarzi, Marc; Scott, Nicholas; Serra, Paolo; Weijmans, Anne-Marie; Young, Lisa M.

2013-07-01

In the companion Paper XV of this series, we derive accurate total mass-to-light ratios (M/L)_JAM≈ (M/L)({r}= {R_e}) within a sphere of radius r= {R_e} centred on the galaxy, as well as stellar (M/L)stars (with the dark matter removed) for the volume-limited and nearly mass-selected (stellar mass M_star ≳ 6× 10^9 { M_{⊙}}) ATLAS3D sample of 260 early-type galaxies (ETGs, ellipticals Es and lenticulars S0s). Here, we use those parameters to study the two orthogonal projections ({M_JAM}, {σ _e}) and ({M_JAM}, {R_e^maj}) of the thin Mass Plane (MP) ({M_JAM}, {σ _e}, {R_e^maj}) which describes the distribution of the galaxy population, where {M_JAM}≡ L× (M/L)_JAM≈ M_star. The distribution of galaxy properties on both projections of the MP is characterized by: (i) the same zone of exclusion (ZOE), which can be transformed from one projection to the other using the scalar virial equation. The ZOE is roughly described by two power laws, joined by a break at a characteristic mass {M_JAM}≈ 3× 10^{10} { M_{⊙}}, which corresponds to the minimum Re and maximum stellar density. This results in a break in the mean {M_JAM}-{σ _e} relation with trends {M_JAM}∝ σ _e^{2.3} and {M_JAM}∝ σ _e^{4.7} at small and large σe, respectively; (ii) a characteristic mass {M_JAM}≈ 2× 10^{11} { M_{⊙}} which separates a population dominated by flat fast rotator with discs and spiral galaxies at lower masses, from one dominated by quite round slow rotators at larger masses; (iii) below that mass the distribution of ETGs' properties on the two projections of the MP tends to be constant along lines of roughly constant σe, or equivalently along lines with {R_e^maj}∝ {M_JAM}, respectively (or even better parallel to the ZOE: {R_e^maj}∝ M_JAM^{0.75}); (iv) it forms a continuous and parallel sequence with the distribution of spiral galaxies; (v) at even lower masses, the distribution of fast-rotator ETGs and late spirals naturally extends to that of dwarf ETGs (Sph

Overview of the 1986--1987 atomic mass predictions

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

Haustein, P.E.

1988-07-01

The need for a comprehensive update of earlier sets of atomic mass predictions is documented. A project that grew from this need and which resulted in the preparation of the 1986--1987 Atomic Mass Predictions is summarized. Ten sets of new mass predictions and expository text from a variety of types of mass models are combined with the latest evaluation of experimentally determined atomic masses. The methodology employed in constructing these mass predictions is outlined. The models are compared with regard to their reproduction of the experimental mass surface and their use of varying numbers of adjustable parameters. Plots are presented,more » for each set of predictions, of differences between model calculations and the measured masses. These plots may be used to estimate the reliability of the new mass predictions in unmeasured regions that border the experimetally known mass surface. copyright 1988 Academic Press, Inc.« less

On the hadron mass decomposition

NASA Astrophysics Data System (ADS)

Lorcé, Cédric

2018-02-01

We argue that the standard decompositions of the hadron mass overlook pressure effects, and hence should be interpreted with great care. Based on the semiclassical picture, we propose a new decomposition that properly accounts for these pressure effects. Because of Lorentz covariance, we stress that the hadron mass decomposition automatically comes along with a stability constraint, which we discuss for the first time. We show also that if a hadron is seen as made of quarks and gluons, one cannot decompose its mass into more than two contributions without running into trouble with the consistency of the physical interpretation. In particular, the so-called quark mass and trace anomaly contributions appear to be purely conventional. Based on the current phenomenological values, we find that in average quarks exert a repulsive force inside nucleons, balanced exactly by the gluon attractive force.

Hadron masses in a gauge theory

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

De Rujula, A.; Georgi, H.; Glashow, S.L.

1975-07-01

We explore the implications for hadron spectroscopy of the ''standard'' gauge model of weak, electromagnetic, and strong interactions. The model involves four types of fractionally charged quarks, each in three colors, coupling to massless gauge gluons. The quarks are confined within colorless hadrons by a long-range spin-independent force realizing infrared slavery. We use the asymptotic freedom of the model to argue that for the calculation of hadron masses, the short-range quark-quark interaction may be taken to be Coulomb- like. We rederive many successful quark-model mass relations for the low-lying hadrons. Because a specific interaction and symmetry-breaking mechanism are forced onmore » us by the underlying renormalizable gauge field theory, we also obtain new mass relations. They are well satisfied. We develop a qualitative understanding of many features of the hadron mass spectrum, such as the origin and sign of the $Sigma$-$lambda$ mass splitting. Interpreting the newly discovered narrow boson resonances as states of charmonium, we use the model to predict the masses of charmed mesons and baryons.« less

Factors that Alter Body Fat, Body Mass, and Fat-Free Mass in Pediatric Obesity.

ERIC Educational Resources Information Center

LeMura, Linda M.; Maziekas, Michael T.

2002-01-01

Investigated the effects of exercise programs on changes in body mass, fat-free mass, and body fat in obese children and adolescents. Research review indicated that exercise effectively helped reduce children's and adolescents' body composition variables. The most favorable body alterations occurred with low- intensity, long-duration exercise;…

Fundamental Parameters Of The Lowest Mass Stars To The Highest Mass Planets

NASA Astrophysics Data System (ADS)

Filippazzo, Joseph C.

2016-09-01

The physical and atmospheric properties of ultracool dwarfs are deeply entangled due to the degenerate effects of mass, age, metallicity, clouds and dust, activity, rotation, and possibly even formation mechanism on observed spectra. Accurate determination of funda- mental parameters for a wide diversity of objects at the low end of the initial mass function (IMF) is thus crucial to testing stellar and planetary formation theories. To determine these quantities, we constructed and flux calibrated nearly-complete spectral energy distributions (SEDs) for 234 M, L, T, and Y dwarfs using published parallaxes and (0.3-40 \\mu m) spectra and photometry. From these homogeneous SEDs, we calculated bolometric luminosity ((L_\\text{bol})), effective temperature ((T_\\text{off})), mass, surface gravity, radius, spectral indexes, synthetic photometry, and bolometric corrections (BCs) for each object. We used these results to derive (L_\\text{bol}), (T_\\text{eff}), and BC polynomial relations across the entire very-low-mass star/brown dwarf/planetary mass regime. We use a subsample of objects with age constraints based on nearby young moving group membership, companionship with a young star, or spectral signatures of low surface gravity to define new age-sensitive diagnostics and characterize the reddening of young substellar atmospheres as a redistribution of flux from the near-infrared (NIR) into the mid-infrared (MIR). Consequently we find the SED flux pivots at K-band, making BCK as a function of spectral type a reliable, age-independent relationship. We find that young L dwarfs are systematically 300 K cooler than field age objects of the same spectral type and up to 600 K cooler than field age objects of the same absolute H magnitude. These findings are used to create prescriptions for the reliable and efficient characterization of new ultracool dwarfs using heterogeneous and limited spectral data.

43 CFR 3106.4-3 - Mass transfers.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Mass transfers. 3106.4-3 Section 3106.4-3... or Otherwise § 3106.4-3 Mass transfers. (a) A mass transfer may be utilized in lieu of the provisions... large number of Federal leases to the same transferee. (b) Three originally executed copies of the mass...

VLTI Imaging of a High-Mass Protobinary System: Unveiling the Dynamical Processes in High-Mass Star Formation

NASA Astrophysics Data System (ADS)

Kraus, S.; Kluska, J.; Kreplin, A.; Bate, M.; Harries, T.; Hofmann, K.-H.; Hone, E.; Monnier, J.; Weigelt, G.; Anugu, N.; de Wit, W.-J..; Wittkowski, M.

2017-12-01

High-mass stars exhibit a significantly higher multiplicity frequency than low-mass stars, likely reflecting differences in how they formed. Theory suggests that high-mass binaries may form by the fragmentation of self-gravitational discs or by alternative scenarios such as disc-assisted capture. Near-infrared interferometric observations reveal the high-mass young stellar object IRAS 17216-3801 to be a close high-mass protobinary with a separation of 0.058 arcseconds ( 170 au). This is the closest high-mass protobinary system imaged to date. We also resolve near- infrared excess emission around the individual stars, which is associated with hot dust in circumstellar discs. These discs are strongly misaligned with respect to the binary separation vector, indicating that tidal forces have not yet had time to realign. We measure a higher accretion rate towards the circumsecondary disc, confirming a hydrodynamic effect where the secondary star disrupts the primary star’s accretion stream and effectively limits the mass that the primary star can accrete. NACO L'-band imaging may also have resolved the circumbinary disc that feeds the accretion onto the circumstellar discs. This discovery demonstrates the unique capabilities of the VLTI, creating exciting new opportunities to study the dynamical processes that govern the architecture of close multiple systems.

Association between fat mass index and fat-free mass index values and cardiovascular risk in adolescents

PubMed Central

de Oliveira, Patrícia Morais; da Silva, Fabiana Almeida; Oliveira, Renata Maria Souza; Mendes, Larissa Loures; Pereira, Michele; Cândido, Ana Paula Carlos

2016-01-01

Abstract Objective: To describe the association between fat mass index and fat-free mass index values and factors associated with cardiovascular risk in adolescents in the city of Juiz de Fora, Minas Gerais. Methods: Cross-sectional study was with 403 adolescents aged 10–14 years, from public and private schools. Anthropometric, clinical, and biochemical measurements were obtained, as well as self-reported time spent performing physical exercises, sedentary activities and sexual maturation stage. Results: Regarding the nutritional status, 66.5% of the adolescents had normal weight, 19.9% were overweight and 10.2% were obese. For both genders, the fat mass index was higher in adolescents who had high serum triglycerides, body mass index and waist circumference. Conclusions: Adolescents who had anthropometric, clinical and biochemical characteristics considered to be at risk for the development of cardiovascular disease had higher values of fat mass index. Different methodologies for the assessment of body composition make health promotion and disease prevention more effective. PMID:26542380

Einstein Never Approved of Relativistic Mass

ERIC Educational Resources Information Center

Hecht, Eugene

2009-01-01

During much of the 20th century it was widely believed that one of the significant insights of special relativity was "relativistic mass." Today there are two schools on that issue: the traditional view that embraces speed-dependent "relativistic mass," and the more modern position that rejects it, maintaining that there is only one mass and it's…

BANYAN. IX. The Initial Mass Function and Planetary-mass Object Space Density of the TW HYA Association

NASA Astrophysics Data System (ADS)

Gagné, Jonathan; Faherty, Jacqueline K.; Mamajek, Eric E.; Malo, Lison; Doyon, René; Filippazzo, Joseph C.; Weinberger, Alycia J.; Donaldson, Jessica K.; Lépine, Sébastien; Lafrenière, David; Artigau, Étienne; Burgasser, Adam J.; Looper, Dagny; Boucher, Anne; Beletsky, Yuri; Camnasio, Sara; Brunette, Charles; Arboit, Geneviève

2017-02-01

A determination of the initial mass function (IMF) of the current, incomplete census of the 10 Myr-old TW Hya association (TWA) is presented. This census is built from a literature compilation supplemented with new spectra and 17 new radial velocities from ongoing membership surveys, as well as a reanalysis of Hipparcos data that confirmed HR 4334 (A2 Vn) as a member. Although the dominant uncertainty in the IMF remains census incompleteness, a detailed statistical treatment is carried out to make the IMF determination independent of binning while accounting for small number statistics. The currently known high-likelihood members are fitted by a log-normal distribution with a central mass of {0.21}-0.06+0.11 M ⊙ and a characteristic width of {0.8}-0.1+0.2 dex in the 12 M Jup-2 M ⊙ range, whereas a Salpeter power law with α ={2.2}-0.5+1.1 best describes the IMF slope in the 0.1-2 M ⊙ range. This characteristic width is higher than other young associations, which may be due to incompleteness in the current census of low-mass TWA stars. A tentative overpopulation of isolated planetary-mass members similar to 2MASS J11472421-2040204 and 2MASS J11193254-1137466 is identified: this indicates that there might be as many as {10}-5+13 similar members of TWA with hot-start model-dependent masses estimated at ˜5-7 M Jup, most of which would be too faint to be detected in 2MASS. Our new radial velocity measurements corroborate the membership of 2MASS J11472421-2040204, and secure TWA 28 (M8.5 γ), TWA 29 (M9.5 γ), and TWA 33 (M4.5 e) as members. The discovery of 2MASS J09553336-0208403, a young L7-type interloper unrelated to TWA, is also presented.

A search for close-mass lepton doublet

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

Riles, J.K.

1989-04-01

Described is a search for a heavy charged lepton with an associated neutrino of nearly the same mass, together known as a close-mass lepton doublet. The search is conducted in e/sup +/e/sup/minus// annihilation data taken with the Mark II detector at a center-of-mass energy of 29 GeV. In order to suppress contamination from conventional two-photon reactions, the search applies a novel, radiative-tagging technique. Requiring the presence of an isolated, energetic photon allows exploration for lepton doublets with a mass splitting smaller than that previously accessible to experiment. No evidence for such a new lepton has been found, enabling limits tomore » be placed on allowed mass combinations. Mass differences as low as 250-300 MeV are excluded for charged lepton masses up to 10 GeV. 78 refs., 64 figs., 8 tabs.« less

Mass Measurement - Skylab Student Experiment ED-74

NASA Technical Reports Server (NTRS)

1973-01-01

Vincent W. Converse of Rockford, Illinois proposed Skylab's student experiment ED-74, Mass Measurement, to measure mass in a weightless environment. This chart describes Converse's experiment. Mass is the quantity of matter in any object. The gravitational force between an object and the Earth is called weight, which is a result of the Earth's gravity acting upon the object's mass. Even though objects in Skylab were apparently weightless, their mass properties were unchanged. Measurement of mass is therefore an acceptable alternative to measurement of weight. The devices used in this experiment provided accurate mass measurements of the astronauts' weights, intakes, and body wastes throughout the missions. In March 1972, NASA and the National Science Teachers Association selected 25 experiment proposals for flight on Skylab. Science advisors from the Marshall Space Flight Center aided and assisted the students in developing the proposals for flight on Skylab.

Higher-speed coronal mass ejections and their geoeffectiveness

NASA Astrophysics Data System (ADS)

Singh, A. K.; Bhargawa, Asheesh; Tonk, Apeksha

2018-06-01

We have attempted to examine the ability of coronal mass ejections to cause geoeffectiveness. To that end, we have investigated total 571 cases of higher-speed (> 1000 km/s) coronal mass ejection events observed during the years 1996-2012. On the basis of angular width (W) of observance, events of coronal mass ejection were further classified as front-side or halo coronal mass ejections (W = 360°); back-side halo coronal mass ejections (W = 360°); partial halo (120°< W < 360°) and non-halo (W < 120°). From further analysis, we found that front halo coronal mass ejections were much faster and more geoeffective in comparison of partial halo and non-halo coronal mass ejections. We also inferred that the front-sided halo coronal mass ejections were 67.1% geoeffective while geoeffectiveness of partial halo coronal mass ejections and non-halo coronal mass ejections were found to be 44.2% and 56.6% respectively. During the same period of observation, 43% of back-sided CMEs showed geoeffectiveness. We have also investigated some events of coronal mass ejections having speed > 2500 km/s as a case study. We have concluded that mere speed of coronal mass ejection and their association with solar flares or solar activity were not mere criterion for producing geoeffectiveness but angular width of coronal mass ejections and their originating position also played a key role.

Precise charm to strange mass ratio and light quark masses from full lattice QCD.

PubMed

Davies, C T H; McNeile, C; Wong, K Y; Follana, E; Horgan, R; Hornbostel, K; Lepage, G P; Shigemitsu, J; Trottier, H

2010-04-02

By using a single formalism to handle charm, strange, and light valence quarks in full lattice QCD for the first time, we are able to determine ratios of quark masses to 1%. For m(c)/m(s) we obtain 11.85(16), an order of magnitude more precise than the current PDG average. Combined with 1% determinations of the charm quark mass now possible this gives m(s)(2 GeV)=92.4(1.5) MeV. The MILC result for m(s)/m(l)=27.2(3) yields m(l)(2 GeV)=3.40(7) MeV for the average of u and d quark masses.

Broad screening of illicit ingredients in cosmetics using ultra-high-performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometry with customized accurate-mass database and mass spectral library.

PubMed

Meng, Xianshuang; Bai, Hua; Guo, Teng; Niu, Zengyuan; Ma, Qiang

2017-12-15

Comprehensive identification and quantitation of 100 multi-class regulated ingredients in cosmetics was achieved using ultra-high-performance liquid chromatography (UHPLC) coupled with hybrid quadrupole-Orbitrap high-resolution mass spectrometry (Q-Orbitrap HRMS). A simple, efficient, and inexpensive sample pretreatment protocol was developed using ultrasound-assisted extraction (UAE), followed by dispersive solid-phase extraction (dSPE). The cosmetic samples were analyzed by UHPLC-Q-Orbitrap HRMS under synchronous full-scan MS and data-dependent MS/MS (full-scan MS 1 /dd-MS 2 ) acquisition mode. The mass resolution was set to 70,000 FWHM (full width at half maximum) for full-scan MS 1 and 17,500 FWHM for dd-MS 2 stage with the experimentally measured mass deviations of less than 2ppm (parts per million) for quasi-molecular ions and 5ppm for characteristic fragment ions for each individual analyte. An accurate-mass database and a mass spectral library were built in house for searching the 100 target compounds. Broad screening was conducted by comparing the experimentally measured exact mass of precursor and fragment ions, retention time, isotopic pattern, and ionic ratio with the accurate-mass database and by matching the acquired MS/MS spectra against the mass spectral library. The developed methodology was evaluated and validated in terms of limits of detection (LODs), limits of quantitation (LOQs), linearity, stability, accuracy, and matrix effect. The UHPLC-Q-Orbitrap HRMS approach was applied for the analysis of 100 target illicit ingredients in 123 genuine cosmetic samples, and exhibited great potential for high-throughput, sensitive, and reliable screening of multi-class illicit compounds in cosmetics. Copyright © 2017 Elsevier B.V. All rights reserved.

Mass Wasting

NASA Image and Video Library

2011-12-06

Mass Wasting is the term given to the process of change on a surface due to gravity things moving downhill due to the force of gravity. Dark streaks mark the slopes of craters and hills in this region of Amazonis Planitia.

Mass Deacidification.

ERIC Educational Resources Information Center

Harris, Carolyn

1979-01-01

Reviews methods being developed for mass deacidification of books to prevent deterioration of paper. The use of diethyl zinc, liquified gas, and morpholine, and the advantages, disadvantages, and cost of each are considered. A 26-item bibliography is included. (JD)

The Mass Index and Total Mass of the Geminid Meteoroid Stream as Found with Radar, Optical, and Lunar Impact Data

NASA Technical Reports Server (NTRS)

Blaauw, R.

2016-01-01

The Geminid meteor shower was observed in 2015 using the Western Meteor Physics Group’s Canadian Meteor Orbit Radar (CMOR), Marshall Space Flight Center’s (MSFC) eight wide-field optical cameras, and MSFC’s lunar impact monitoring. These observations allowed Geminid fluxes to be calculated in three unique mass-ranges, from 1.8 (exponent -4) grams to 30 grams. From these fluxes, a mass index of 1.68 plus or minus 0.04 is found, which is in excellent agreement with past Geminid mass indices such as 1.69 found by Blaauw et al using only radar data and 1.7 found by Arlt and Rendtel using visual data. This mass index, however, is found over five orders of magnitude of mass, which allows a higher level of confidence that this mass index holds over a large portion of the stream. Mass indices are an important quantity to be accurately measured for a shower, indicating the distribution of mass in a well-studied stream in which we know the parent body (3200 Phaethon), improving forecasts of the shower activity, and allow fluxes to be scaled to high and low masses. The quantities derived here, along with a profile of the Geminid meteor shower activity in 2015 from CMOR, permit the total Geminid mass the Earth encountered in 2015 to be found, along with a minimum total mass of the Geminid meteoroid stream. Attempts have been made in the past to measure the mass of meteoroid streams using Zenithal Hourly Rate (ZHR) profiles, but here this new and improved treatment uses empirically derived fluxes and measured mass indices for the 2015 encounter with the meteoroid stream. This is to be compared with other meteoroid stream mass estimates including that of the Perseids, caused by comet Swift Tuttle.

Organized chaos: scatter in the relation between stellar mass and halo mass in small galaxies

NASA Astrophysics Data System (ADS)

Garrison-Kimmel, Shea; Bullock, James S.; Boylan-Kolchin, Michael; Bardwell, Emma

2017-01-01

We use Local Group galaxy counts together with the ELVIS N-body simulations to explore the relationship between the scatter and slope in the stellar mass versus halo mass relation at low masses, M⋆ ≃ 105-108 M⊙. Assuming models with lognormal scatter about a median relation of the form M_star ∝ M_halo^α, the preferred log-slope steepens from α ≃ 1.8 in the limit of zero scatter to α ≃ 2.6 in the case of 2 dex of scatter in M⋆ at fixed halo mass. We provide fitting functions for the best-fitting relations as a function of scatter, including cases where the relation becomes increasingly stochastic with decreasing mass. We show that if the scatter at fixed halo mass is large enough (≳ 1 dex) and if the median relation is steep enough (α ≳ 2), then the `too-big-to-fail' problem seen in the Local Group can be self-consistently eliminated in about ˜5-10 per cent of realizations. This scenario requires that the most massive subhaloes host unobservable ultra-faint dwarfs fairly often; we discuss potentially observable signatures of these systems. Finally, we compare our derived constraints to recent high-resolution simulations of dwarf galaxy formation in the literature. Though simulation-to-simulation scatter in M⋆ at fixed Mhalo is large among different authors (˜2 dex), individual codes produce relations with much less scatter and usually give relations that would overproduce local galaxy counts.

AGN host galaxy mass function in COSMOS. Is AGN feedback responsible for the mass-quenching of galaxies?

NASA Astrophysics Data System (ADS)

Bongiorno, A.; Schulze, A.; Merloni, A.; Zamorani, G.; Ilbert, O.; La Franca, F.; Peng, Y.; Piconcelli, E.; Mainieri, V.; Silverman, J. D.; Brusa, M.; Fiore, F.; Salvato, M.; Scoville, N.

2016-04-01

We investigate the role of supermassive black holes in the global context of galaxy evolution by measuring the host galaxy stellar mass function (HGMF) and the specific accretion rate, that is, λSAR, the distribution function (SARDF), up to z ~ 2.5 with ~1000 X-ray selected AGN from XMM-COSMOS. Using a maximum likelihood approach, we jointly fit the stellar mass function and specific accretion rate distribution function, with the X-ray luminosity function as an additional constraint. Our best-fit model characterizes the SARDF as a double power-law with mass-dependent but redshift-independent break, whose low λSAR slope flattens with increasing redshift while the normalization increases. This implies that for a given stellar mass, higher λSAR objects have a peak in their space density at earlier epoch than the lower λSAR objects, following and mimicking the well-known AGN cosmic downsizing as observed in the AGN luminosity function. The mass function of active galaxies is described by a Schechter function with an almost constant M∗⋆ and a low-mass slope α that flattens with redshift. Compared to the stellar mass function, we find that the HGMF has a similar shape and that up to log (M⋆/M⊙) ~ 11.5, the ratio of AGN host galaxies to star-forming galaxies is basically constant (~10%). Finally, the comparison of the AGN HGMF for different luminosity and specific accretion rate subclasses with a previously published phenomenological model prediction for the "transient" population, which are galaxies in the process of being mass-quenched, reveals that low-luminosity AGN do not appear to be able to contribute significantly to the quenching and that at least at high masses, that is, M⋆ > 1010.7 M⊙, feedback from luminous AGN (log Lbol ≳ 46 [erg/s]) may be responsible for the quenching of star formation in the host galaxy.

A mass graph-based approach for the identification of modified proteoforms using top-down tandem mass spectra

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

Kou, Qiang; Wu, Si; Tolić, Nikola

Motivation: Although proteomics has rapidly developed in the past decade, researchers are still in the early stage of exploring the world of complex proteoforms, which are protein products with various primary structure alterations resulting from gene mutations, alternative splicing, post-translational modifications, and other biological processes. Proteoform identification is essential to mapping proteoforms to their biological functions as well as discovering novel proteoforms and new protein functions. Top-down mass spectrometry is the method of choice for identifying complex proteoforms because it provides a “bird’s eye view” of intact proteoforms. The combinatorial explosion of various alterations on a protein may result inmore » billions of possible proteoforms, making proteoform identification a challenging computational problem. Results: We propose a new data structure, called the mass graph, for efficient representation of proteoforms and design mass graph alignment algorithms. We developed TopMG, a mass graph-based software tool for proteoform identification by top-down mass spectrometry. Experiments on top-down mass spectrometry data sets showed that TopMG outperformed existing methods in identifying complex proteoforms.« less

The solar cycle variation of coronal mass ejections and the solar wind mass flux

NASA Technical Reports Server (NTRS)

Webb, David F.; Howard, Russell A.

1994-01-01

Coronal mass ejections (CMEs) are an important aspect of coronal physics and a potentially significant contributor to perturbations of the solar wind, such as its mass flux. Sufficient data on CMEs are now available to permit study of their longer-term occurrency patterns. Here we present the results of a study of CME occurrence rates over more than a complete 11-year solar sunspot cycle and a comparison of these rates with those of other activity related to CMEs and with the solar wind particle flux at 1 AU. The study includes an evaluation of correlations to the CME rates, which include instrument duty cycles, visibility functions, mass detection thresholds, and geometrical considerations. The main results are as follows: (1) The frequency of occurrence of CMEs tends to track the solar activity cycle in both amplitude and phase; (2) the CME rates from different instruments, when corrected for both duty cycles and visibility functions, are reasonably consistent; (3) considering only longer-term averages, no one class of solar activity is better correlated with CME rate than any other; (4) the ratio of the annualized CME to solar wind mass flux tends to track the solar cycle; and (5) near solar maximum, CMEs can provide a significant fraction (i.e., approximately equals 15%) of the average mass flux to the near-ecliptic solar wind.

On the Mass Distribution of Animal Species

NASA Astrophysics Data System (ADS)

Redner, Sidney; Clauset, Aaron; Schwab, David

2009-03-01

We develop a simple diffusion-reaction model to account for the broad and asymmetric distribution of adult body masses for species within related taxonomic groups. The model assumes three basic evolutionary features that control body mass: (i) a fixed lower limit that is set by metabolic constraints, (ii) a species extinction risk that is a weakly increasing function of body mass, and (iii) cladogenetic diffusion, in which daughter species have a slight tendency toward larger mass. The steady-state solution for the distribution of species masses in this model can be expressed in terms of the Airy function. This solution gives mass distributions that are in good agreement with data on 4002 terrestrial mammal species from the late Quaternary and 8617 extant bird species.

Thiol-based Redox Proteins in Brassica napus Guard Cell Abscisic Acid and Methyl Jasmonate Signaling

PubMed Central

Zhu, Mengmeng; Zhu, Ning; Song, Wen-yuan; Harmon, Alice C.; Assmann, Sarah M.; Chen, Sixue

2014-01-01

SUMMARY Reversibly oxidized cysteine sulfhydryl groups serve as redox sensors or targets of redox sensing that are important in different physiological processes. Little is known, however, about redox sensitive proteins in guard cells and how they function in stomatal signaling. In this study, Brassica napus guard cell proteins altered by redox in response to abscisic acid (ABA) or methyl jasmonate (MeJA) were identified by complementary proteomics approaches, saturation differential in-gel electrophoresis (DIGE) and isotope-coded affinity tag (ICAT). In total, 65 and 118 potential redox responsive proteins were identified in ABA and MeJA treated guard cells, respectively. All the proteins contain at least one cysteine, and over half of them are predicted to form intra-molecular disulfide bonds. Most of the proteins fall into the functional groups of energy, stress and defense, and metabolism. Based on the peptide sequences identified by mass spectrometry, 30 proteins were common to ABA and MeJA treated samples. A total of 44 cysteines was mapped in all the identified proteins, and their levels of redox sensitivity were quantified. Two of the proteins, a SNRK2 kinase and an isopropylmalate dehydrogenase were confirmed to be redox regulated and involved in stomatal movement. This study creates an inventory of potential redox switches, and highlights a protein redox regulatory mechanism in guard cell ABA and MeJA signal transduction. PMID:24580573

The mass function of Seyfert 1 nuclei

NASA Technical Reports Server (NTRS)

Padovani, P.; Burg, R.; Edelson, R. A.

1990-01-01

The first mass function of Seyfert 1 nuclei is derived from optical spectra of the complete CfA sample of Seyfert galaxies by estimating the mass for each object from a dynamical relation. An independent estimate is also derived using a complete infrared-selected sample. The two mass functions are indistinguishable. The mean mass of Seyfert 1 nuclei is about 2 x 10 to the 7th solar masses, and the integrated mass density is about 6 x 10 to the 11th solar masses/cu Gpc. This is approximately two orders of magnitude less than the value inferred from the energetics associated with quasar counts. A careful analysis of the various parameters and assumptions involved suggests that this large difference is not due to systematic errors in the determinations. Therefore, the bulk of mass related to the accretion processes connected with past quasar activity does not reside in Seyfert 1 nuclei. Instead, the remnants of past activity must be present in a much larger number of galaxies, and a one-to-one relation between distant and local active galactic nuclei seems then to be excluded.

Quark-mass dependence of two-nucleon observables

NASA Astrophysics Data System (ADS)

Chen, Jiunn-Wei; Lee, Tze-Kei; Liu, C.-P.; Liu, Yu-Sheng

2012-11-01

We study the potential implications of lattice QCD determinations of the S-wave nucleon-nucleon scattering lengths with unphysical light quark masses. If the light quark masses are small enough such that nuclear effective field theory (NEFT) can be used to perform quark-mass extrapolations, then the leading quark-mass dependence of not only the effective range and the two-body current, but also all the low-energy deuteron matrix elements up to next-to-leading-order in NEFT can be obtained. As a proof of principle, we compute the quark-mass dependence of the deuteron charge radius, magnetic moment, polarizability, and the deuteron photodisintegration cross section using the lattice calculation of the scattering lengths at 354 MeV pion mass by the ``Nuclear Physics with Lattice QCD'' (NPLQCD) collaboration and the NEFT power counting scheme of Beane, Kaplan, and Vuorinen (BKV), even though it is not yet established that the 354 MeV pion mass is within the radius of convergence of the BKV scheme. Once the lattice result with quark mass within the NEFT radius of convergence is obtained, our observation can be used to constrain the time variation of isoscalar combination of u and d quark mass mq, to help the anthropic principle study to find the mq range that allows the existence of life, and to provide a weak test of the multiverse conjecture.

The mass distribution of Population III stars

NASA Astrophysics Data System (ADS)

Fraser, M.; Casey, A. R.; Gilmore, G.; Heger, A.; Chan, C.

2017-06-01

Extremely metal-poor (EMP) stars are uniquely informative on the nature of massive Population III stars. Modulo a few elements that vary with stellar evolution, the present-day photospheric abundances observed in EMP stars are representative of their natal gas cloud composition. For this reason, the chemistry of EMP stars closely reflects the nucleosynthetic yields of supernovae from massive Population III stars. Here we collate detailed abundances of 53 EMP stars from the literature and infer the masses of their Population III progenitors. We fit a simple initial mass function (IMF) to a subset of 29 of the inferred Population III star masses, and find that the mass distribution is well represented by a power-law IMF with exponent α = 2.35^{+0.29}_{-0.24}. The inferred maximum progenitor mass for supernovae from massive Population III stars is M_{max} = 87^{+13}_{-33} M⊙, and we find no evidence in our sample for a contribution from stars with masses above ˜120 M⊙. The minimum mass is strongly consistent with the theoretical lower mass limit for Population III supernovae. We conclude that the IMF for massive Population III stars is consistent with the IMF of present-day massive stars and there may well have formed stars much below the supernova mass limit that could have survived to the present day.

The P-factor and atomic mass systematics: Application to medium mass nuclei

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

Brenner, D.S.; Haustein, P.E.; Casten, R.F.

1988-01-01

The P formalism was applied to atomic mass systematics for medium and heavy nuclei. The P-factor linearizes the structure-dependent part of the nuclear mass in those regions which are free from subshell effects indicating that the attractive quadrupole p-n force plays an important role in determining the binding of valence nucleons. Where marked non-linearities occur, the P-factor provides a means for recognizing subshell closures and/or other structural features not embodied in the simple assumptions of abrupt shell or subshell changes. These are thought to be regions where the monopole part of the p-n interaction is highly orbit dependent and altersmore » the underlying single-particle structure as a function of A, N or Z. Finally, in those regions where the systematics are smooth and subshells are absent, the P-factor provides a means for predicting masses of some nuclei far-from-stability by interpolation rather than by extrapolation. 5 figs.« less

Microcantilevers track single-cell mass

USDA-ARS?s Scientific Manuscript database

Determining the mass of objects by weighing them has been an everyday practice that informs all manner of decisions. However, direct measurement of the mass of sub-microgram objects, especially in fluid, is still a technological grand challenge. Recent advances in microscale cantilever sensors have ...

Calculate Your Body Mass Index

MedlinePlus

... Professional Resources Calculate Your Body Mass Index Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. Enter your weight and height using standard or metric measures. Select "Compute BMI" and your ...

Accurate Mass Determination of Organotrifluoroborates

PubMed Central

Petrillo, Daniel E.; Kohli, Rakesh K.; Molander, Gary A.

2007-01-01

Exact mass measurements were obtained for a variety of potassium- and tetra-n-butylammonium organotrifluoroborates using commercially available organic sulfate salts as internal reference standards. Accuracies were determined within 5 ppm using a sector ESI mass spectrometer operating in the negative ionization mode. PMID:17112738

Preliminary Results in Asteroid Mass Determination

NASA Astrophysics Data System (ADS)

Aslan, Z.; Gumerov, R. I.; Hudkova, L. A.; Ivantsov, A. V.; Khamitov, I.; Pinigin, G. I.

2006-08-01

Asteroid masses are extremely important for the determination of their bulk densities, especially for the discussed relatively high porosities in about 20 to 30% of the studied bodies. The problem will have some coverage in clarifying errors of both mass and volume determinations. We have used lists of encounters for massive and less massive asteroids, prepared by J.L. Hilton, which cover relatively contemporary period of optical observations, 1950-2005. These observations were taken from the MPC database of observations. The model of the motions uses integrations of relativistic equations for perturbing asteroids (Ceres, Pallas, Vesta, and others concerned), perturbed asteroid. Positions and velocities of the Sun and large planets are directly taken from the DE405. The necessary initial conditions were taken from the HORIZONS system. By the adjustment of dynamical model parameters (both initial conditions and perturbing masses for asteroids) there were determined preliminary masses (in 10^-10 of Sun mass) for seven asteroids: (7) Iris 0.090±0.008, (10) Hygiea 0.213±0.030, (24) Themis 0.010±0.024, (45) Eugenia 0.012±0.025, (52) Europa 0.362±0.041, (87) Sylvia 0.180±0.090, (165) Loreley 0.157±0.100. These masses were calculated from difficult cases, where the earlier study by some authors gave negative masses in the unweighted calculations. The values obtained were compared with other estimations. Both the two-fold increase in the number of observations up the present and the active boundary on the determined mass parameter or equivalent logarithm transform should have given physically meaningful values in any case.

Pulmonary Hyperinflation and Left Ventricular Mass

PubMed Central

Smith, Benjamin M; Kawut, Steven M.; Bluemke, David A; Basner, Robert C; Gomes, Antoinette S; Hoffman, Eric; Kalhan, Ravi; Lima, João AC; Liu, Chia-Ying; Michos, Erin D; Prince, Martin R; Rabbani, LeRoy; Rabinowitz, Daniel; Shimbo, Daichi; Shea, Steven; Barr, R Graham

2013-01-01

Background Left ventricular (LV) mass is an important predictor of heart failure and cardiovascular mortality, yet determinants of LV mass are incompletely understood. Pulmonary hyperinflation in chronic obstructive pulmonary disease (COPD) may contribute to changes in intrathoracic pressure that increase LV wall stress. We therefore hypothesized that residual lung volume in COPD would be associated with greater LV mass. Methods and results The Multi-Ethnic Study of Atherosclerosis (MESA) COPD Study recruited smokers aged 50–79 years who were free of clinical cardiovascular disease. LV mass was measured by cardiac magnetic resonance. Pulmonary function testing was performed according to guidelines. Regression models were used to adjust for age, sex, body size, blood pressure and other cardiac risk factors. Among 119 MESA COPD Study participants, mean age was 69±6 years, 55% were male and 65% had COPD, mostly of mild or moderate severity. Mean LV mass was 128±34 grams. Residual lung volume was independently associated with greater LV mass (7.2 grams per standard deviation increase in residual volume; 95% CI 2.2 to 12; P=0.004), and was similar in magnitude to that of systolic blood pressure (7.6 grams per standard deviation increase in systolic blood pressure, 95% CI 4.3 to 11 grams; p<0.001). Similar results were observed for LV mass to end-diastolic volume ratio (p=0.02) and with hyperinflation measured as residual volume to total lung capacity ratio (P=0.009). Conclusions Pulmonary hyperinflation, as measured by residual lung volume or residual lung volume to total lung capacity ratio, is associated with greater LV mass. PMID:23493320

Electrophoresis-mass spectrometry probe

DOEpatents

Andresen, B.D.; Fought, E.R.

1987-11-10

The invention involves a new technique for the separation of complex mixtures of chemicals, which utilizes a unique interface probe for conventional mass spectrometers which allows the electrophoretically separated compounds to be analyzed in real-time by a mass spectrometer. This new chemical analysis interface, which couples electrophoresis with mass spectrometry, allows complex mixtures to be analyzed very rapidly, with much greater specificity, and with greater sensitivity. The interface or probe provides a means whereby large and/or polar molecules in complex mixtures to be completely characterized. The preferred embodiment of the probe utilizes a double capillary tip which allows the probe tip to be continually wetted by the buffer, which provides for increased heat dissipation, and results in a continually operating interface which is more durable and electronically stable than the illustrated single capillary tip probe interface. 8 figs.

Electrophoresis-mass spectrometry probe

DOEpatents

Andresen, Brian D.; Fought, Eric R.

1987-01-01

The invention involves a new technique for the separation of complex mixtures of chemicals, which utilizes a unique interface probe for conventional mass spectrometers which allows the electrophoretically separated compounds to be analyzed in real-time by a mass spectrometer. This new chemical analysis interface, which couples electrophoresis with mass spectrometry, allows complex mixtures to be analyzed very rapidly, with much greater specificity, and with greater sensitivity. The interface or probe provides a means whereby large and/or polar molecules in complex mixtures to be completely characterized. The preferred embodiment of the probe utilizes a double capillary tip which allows the probe tip to be continually wetted by the buffer, which provides for increased heat dissipation, and results in a continually operating interface which is more durable and electronically stable than the illustrated single capillary tip probe interface.

Mass spectrometry of aerospace materials

NASA Technical Reports Server (NTRS)

Colony, J. A.

1976-01-01

Mass spectrometry is used for chemical analysis of aerospace materials and contaminants. Years of analytical aerospace experience have resulted in the development of specialized techniques of sampling and analysis which are required in order to optimize results. This work has resulted in the evolution of a hybrid method of indexing mass spectra which include both the largest peaks and the structurally significant peaks in a concise format. With this system, a library of mass spectra of aerospace materials was assembled, including the materials responsible for 80 to 90 percent of the contamination problems at Goddard Space Flight Center during the past several years.

Clockwork for neutrino masses and lepton flavor violation

NASA Astrophysics Data System (ADS)

Ibarra, Alejandro; Kushwaha, Ashwani; Vempati, Sudhir K.

2018-05-01

We investigate the generation of small neutrino masses in a clockwork framework which includes Dirac mass terms as well as Majorana mass terms for the new fermions. We derive analytic formulas for the masses of the new particles and for their Yukawa couplings to the lepton doublets, in the scenario where the clockwork parameters are universal. When the universal Majorana mass vanishes, the zero mode of the clockwork sector forms a Dirac pair with the active neutrino, with a mass which is in agreement with oscillations experiments for a sufficiently large number of clockwork gears. On the other hand, when it does not vanish, neutrino masses are generated via the seesaw mechanism. In this case, and due to the fact that the effective Yukawa couplings of the higher modes can be sizable, neutrino masses can only be suppressed by postulating a large Majorana mass scale. Finally, we discuss the constraints on the mass scale of the clockwork fermions from the non-observation of the rare leptonic decay μ → eγ.

Space Technology 7 : Micropropulsion and Mass Distribution

NASA Technical Reports Server (NTRS)

Carnaub, A.; Dunn, C.; Ziemer, J,; Hruby, V.; Spence, D.; Demmons, N.; Roy, T.; McCormick, R.; Gasaska, C.; Young, J.;