20 CFR 348.1 - Introduction.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Introduction. 348.1 Section 348.1 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT REPRESENTATIVE... Railroad Retirement Act, which is also applicable to the Railroad Unemployment Insurance Act, provides that...

20 CFR 348.1 - Introduction.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Introduction. 348.1 Section 348.1 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT REPRESENTATIVE... Railroad Retirement Act, which is also applicable to the Railroad Unemployment Insurance Act, provides that...

20 CFR 348.1 - Introduction.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Introduction. 348.1 Section 348.1 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT REPRESENTATIVE... Railroad Retirement Act, which is also applicable to the Railroad Unemployment Insurance Act, provides that...

20 CFR 348.1 - Introduction.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Introduction. 348.1 Section 348.1 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT REPRESENTATIVE... Railroad Retirement Act, which is also applicable to the Railroad Unemployment Insurance Act, provides that...

Crack Arrest Toughness of Two High Strength Steels (AISI 4140 and AISI 4340)

NASA Astrophysics Data System (ADS)

Ripling, E. J.; Mulherin, J. H.; Crosley, P. B.

1982-04-01

The crack initiation toughness ( K c ) and crack arrest toughness ( K a ) of AISI 4140 and AISI 4340 steel were measured over a range of yield strengths from 965 to 1240 MPa, and a range of test temperatures from -53 to +74°C. Emphasis was placed on K a testing since these values are thought to represent the minimum toughness of the steel as a function of loading rate. At the same yield strengths and test temperatures, K a for the AISI 4340 was about twice as high as it was for the AISI 4140. In addition, the K a values showed a more pronounced transition temperature than the K c values, when the data were plotted as a function of test temperature. The transition appeared to be associated with a change in fracture mechanism from cleavage to dimpled rupture as the test temperature was increased. The occurrence of a “pop-in” behavior at supertransition temperatures has not been found in lower strength steels, and its evaluation in these high strength steels was possible only because they are not especially tough at their supertransition temperatures. There is an upper toughness limit at which pop-in will not occur, and this was found for the AISI 4340 steel when it was tempered to its lowest yield strength (965 MPa). All the crack arrest data were identified as plane strain values, while only about one-half of the initiation values could be classified this way.

18 CFR 34.8 - Verification.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Verification. 34.8 Section 34.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT APPLICATION FOR AUTHORIZATION OF THE ISSUANCE OF...

18 CFR 348.2 - Procedures.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Procedures. 348.2 Section 348.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE INTERSTATE COMMERCE ACT OIL PIPELINE APPLICATIONS FOR MARKET POWER...

13 CFR 120.348 - Amount of guarantee.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Amount of guarantee. 120.348 Section 120.348 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans International Trade Loans § 120.348 Amount of guarantee. SBA can guarantee up to $1,250,000...

The effect of nitrogen gas flow rate on heat treatment of AISI SS-430: Study of microstructure and hardness

NASA Astrophysics Data System (ADS)

Sebayang, Perdamean; Darmawan, Bobby Aditya; Simbolon, Silviana; Alfirano, Sudiro, Toto; Aryanto, Didik

2018-05-01

The aim of this research was to obtain the austenite phase from ferritic stainless steel through sample heat treatment. The AISI 430 ferritic steel with the thickness of about 0.4 mm was used. The heat treatment was conducted in a tube furnace at elevated temperature of 1150, 1200, 1250 °C and nitrogen gas flow rate of 0.57 and 0.73 l/s. The samples were then rapidly quenched in water bath. An optical microscope, XRD, SEM-EDS and micro vickers hardness tester were used to characterize the sample before and after het treatment. The presence of anneal twins indicated the formation of austenite phase in the sample. Its fraction was varied from 10.89 wt% to 35.10 wt%. In addition, the heat treatment temperature strongly affected the sample hardness. The optimum hardness obtained was about 542.69 HV. According to the results, this material can be considered for biomedical applications.

10 CFR 2.348 - Separation of functions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Separation of functions. 2.348 Section 2.348 Energy... Adjudicatory Hearings § 2.348 Separation of functions. (a) In any proceeding under this part, any NRC officer or employee engaged in the performance of any investigative or litigating function in the proceeding...

Electrochemical Evaluation of Stainless Steels in Acidified Sodium Chloride Solutions

NASA Technical Reports Server (NTRS)

Calle, L. M.; MacDowell, L. G.; Vinje, R. D.

2004-01-01

This paper presents the results of an investigation in which several 300-series stainless steels (SS): AISI S30403 SS (UNS S30403), AISI 316L SS (UNS S31603), and AISI 317L SS (LINS S31703), as well as highly-alloyed: SS 254-SMO (UNS S32154), AL-6XN (N08367) and AL29-4C (UNS S44735), were evaluated using DC electrochemical techniques in three different electrolyte solutions. The solutions consisted of neutral 3.55% NaCl, 3.55% NaCl in 0.1N HCl, and 3.55% NaCl in 1.0N HCl. These solutions were chosen to simulate environments that are less, similar, and more aggressive, respectively, than the conditions at the Space Shuttle launch pads. The electrochemical test results were compared to atmospheric exposure data and evaluated for their ability to predict the long-term corrosion performance of the subject alloys. The electrochemical measurements for the six alloys indicated that the higher-alloyed SS 254-SMO, AL29-4C, and AL-6XN exhibited significantly higher resistance to localized corrosion than the 300-series SS. There was a correlation between the corrosion performance of the alloys during a two-year atmospheric exposure and the corrosion rates calculated from electrochemical (polarization resistance) measurements.

13 CFR 120.348 - Amount of guarantee.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Purpose Loans International Trade Loans § 120.348 Amount of guarantee. The maximum loan amount for any one International Trade (IT) loan is $5,000,000. IT loans may receive a maximum guaranty of 90 percent or $4,500,000...

Characterization of AISI 4140 borided steels

NASA Astrophysics Data System (ADS)

Campos-Silva, I.; Ortiz-Domínguez, M.; López-Perrusquia, N.; Meneses-Amador, A.; Escobar-Galindo, R.; Martínez-Trinidad, J.

2010-02-01

The present study characterizes the surface of AISI 4140 steels exposed to the paste-boriding process. The formation of Fe 2B hard coatings was obtained in the temperature range 1123-1273 K with different exposure times, using a 4 mm thick layer of boron carbide paste over the material surface. First, the growth kinetics of boride layers at the surface of AISI 4140 steels was evaluated. Second, the presence and distribution of alloying elements on the Fe 2B phase was measured using the Glow Discharge Optical Emission Spectrometry (GDOES) technique. Further, thermal residual stresses produced on the borided phase were evaluated by X-ray diffraction (XRD) analysis. The fracture toughness of the iron boride layer of the AISI 4140 borided steels was estimated using a Vickers microindentation induced-fracture testing at a constant distance of 25 μm from the surface. The force criterion of fracture toughness was determined from the extent of brittle cracks, both parallel and perpendicular to the surface, originating at the tips of an indenter impression. The fracture toughness values obtained by the Palmqvist crack model are expressed in the form KC( π/2) > KC > KC(0) for the different applied loads and experimental parameters of the boriding process.

Hot-corrosion of AISI 1020 steel in a molten NaCl/Na2SO4 eutectic at 700°C

NASA Astrophysics Data System (ADS)

Badaruddin, Mohammad; Risano, Ahmad Yudi Eka; Wardono, Herry; Asmi, Dwi

2017-01-01

Hot-corrosion behavior and morphological development of AISI 1020 steel with 2 mg cm-2 mixtures of various NaCl/Na2SO4 ratios at 700°C were investigated by means of weight gain measurements, Optical Microscope (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). The weight gain kinetics of the steel with mixtures of salt deposits display a rapid growth rates, compared with the weight gain kinetics of AISI 1020 steel without salt deposit in dry air oxidation, and follow a steady-state parabolic law for 49 h. Chloridation and sulfidation produced by a molten NaCl/Na2SO4 on the steel induced hot-corrosion mechanism attack, and are responsible for the formation of thicker scale. The most severe corrosion takes place with the 70 wt.% NaCl mixtures in Na2SO4. The typical Fe2O3 whisker growth in outer part scale was attributed to the FeCl3 volatilization. The formation of FeS in the innermost scale is more pronounced as the content of Na2SO4 in the mixture is increased.

10 CFR 34.8 - Information collection requirements: OMB approval.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Information collection requirements: OMB approval. 34.8 Section 34.8 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS General Provisions § 34.8 Information collection...

10 CFR 34.8 - Information collection requirements: OMB approval.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Information collection requirements: OMB approval. 34.8 Section 34.8 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS General Provisions § 34.8 Information collection...

10 CFR 34.8 - Information collection requirements: OMB approval.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Information collection requirements: OMB approval. 34.8 Section 34.8 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS General Provisions § 34.8 Information collection...

10 CFR 34.8 - Information collection requirements: OMB approval.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Information collection requirements: OMB approval. 34.8 Section 34.8 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS General Provisions § 34.8 Information collection...

10 CFR 34.8 - Information collection requirements: OMB approval.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Information collection requirements: OMB approval. 34.8 Section 34.8 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS General Provisions § 34.8 Information collection...

Brucella Rough Mutant Induce Macrophage Death via Activating IRE1α Pathway of Endoplasmic Reticulum Stress by Enhanced T4SS Secretion

PubMed Central

Li, Peng; Tian, Mingxing; Bao, Yanqing; Hu, Hai; Liu, Jiameng; Yin, Yi; Ding, Chan; Wang, Shaohui; Yu, Shengqing

2017-01-01

Brucella is a Gram-negative facultative intracellular pathogen that causes the worldwide zoonosis, known as brucellosis. Brucella virulence relies mostly on its ability to invade and replicate within phagocytic cells. The type IV secretion system (T4SS) and lipopolysaccharide are two major Brucella virulence factors. Brucella rough mutants reportedly induce the death of infected macrophages, which is T4SS dependent. However, the underlying molecular mechanism remains unclear. In this study, the T4SS secretion capacities of Brucella rough mutant and its smooth wild-type strain were comparatively investigated, by constructing the firefly luciferase fused T4SS effector, BPE123 and VceC. In addition, quantitative real-time PCR and western blotting were used to analyze the T4SS expression. The results showed that T4SS expression and secretion were enhanced significantly in the Brucella rough mutant. We also found that the activity of the T4SS virB operon promoter was notably increased in the Brucella rough mutant, which depends on quorum sensing-related regulators of VjbR upregulation. Cell infection and cell death assays revealed that deletion of vjbR in the Brucella rough mutant absolutely abolished cytotoxicity within macrophages by downregulating T4SS expression. This suggests that up-regulation of T4SS promoted by VjbR in rough mutant ΔrfbE contribute to macrophage death. In addition, we found that the Brucella rough mutant induce macrophage death via activating IRE1α pathway of endoplasmic reticulum stress. Taken together, our study provide evidence that in comparison to the Brucella smooth wild-type strain, VjbR upregulation in the Brucella rough mutant increases transcription of the virB operon, resulting in overexpression of the T4SS gene, accompanied by the over-secretion of effecter proteins, thereby causing the death of infected macrophages via activating IRE1α pathway of endoplasmic reticulum stress, suggesting novel insights into the molecular

Brucella Rough Mutant Induce Macrophage Death via Activating IRE1α Pathway of Endoplasmic Reticulum Stress by Enhanced T4SS Secretion.

PubMed

Li, Peng; Tian, Mingxing; Bao, Yanqing; Hu, Hai; Liu, Jiameng; Yin, Yi; Ding, Chan; Wang, Shaohui; Yu, Shengqing

2017-01-01

Brucella is a Gram-negative facultative intracellular pathogen that causes the worldwide zoonosis, known as brucellosis. Brucella virulence relies mostly on its ability to invade and replicate within phagocytic cells. The type IV secretion system (T4SS) and lipopolysaccharide are two major Brucella virulence factors. Brucella rough mutants reportedly induce the death of infected macrophages, which is T4SS dependent. However, the underlying molecular mechanism remains unclear. In this study, the T4SS secretion capacities of Brucella rough mutant and its smooth wild-type strain were comparatively investigated, by constructing the firefly luciferase fused T4SS effector, BPE123 and VceC. In addition, quantitative real-time PCR and western blotting were used to analyze the T4SS expression. The results showed that T4SS expression and secretion were enhanced significantly in the Brucella rough mutant. We also found that the activity of the T4SS virB operon promoter was notably increased in the Brucella rough mutant, which depends on quorum sensing-related regulators of VjbR upregulation. Cell infection and cell death assays revealed that deletion of vjbR in the Brucella rough mutant absolutely abolished cytotoxicity within macrophages by downregulating T4SS expression. This suggests that up-regulation of T4SS promoted by VjbR in rough mutant Δ rfbE contribute to macrophage death. In addition, we found that the Brucella rough mutant induce macrophage death via activating IRE1α pathway of endoplasmic reticulum stress. Taken together, our study provide evidence that in comparison to the Brucella smooth wild-type strain, VjbR upregulation in the Brucella rough mutant increases transcription of the virB operon, resulting in overexpression of the T4SS gene, accompanied by the over-secretion of effecter proteins, thereby causing the death of infected macrophages via activating IRE1α pathway of endoplasmic reticulum stress, suggesting novel insights into the molecular

42 CFR 413.348 - Limitation on review.

Code of Federal Regulations, 2011 CFR

2011-10-01

... payment rates, the case-mix methodology, and the development and application of the wage index. This... 42 Public Health 2 2011-10-01 2011-10-01 false Limitation on review. 413.348 Section 413.348 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE...

IFNL4 ss469415590 Variant Is Associated with Treatment Response in Japanese HCV Genotype 1 Infected Individuals Treated with IFN-Including Regimens

PubMed Central

Miyamura, Tatsuo; Kanda, Tatsuo; Nakamoto, Shingo; Arai, Makoto; Nakamura, Masato; Wu, Shuang; Jiang, Xia; Sasaki, Reina; Yasui, Shin; Ooka, Yoshihiko; Imazeki, Fumio; Mikami, Shigeru; Yokosuka, Osamu

2014-01-01

Aim. Eradication of hepatitis C virus (HCV) is still challenging even if interferon- (IFN-) free regimens with direct-acting antiviral agents (DAAs) for HCV-infected individuals are available in clinical practice. IFNL4 is a newly described protein, associated with human antiviral defenses. We investigated whether IFNL4 ss469415590 variant has an effect on the prediction of treatment response in HCV-infected patients treated with IFN-including regimens. Patients and Methods. In all, 185 patients infected with HCV genotype 1 treated with peg-IFN plus ribavirin, with or without telaprevir, were genotyped for IFNL4 ss469415590. We retrospectively investigated whether the role of IFNL4 ss469415590 variant and other factors could predict sustained virological response (SVR) in Japanese patients infected with HCV genotype 1. Results. There were 65.7%, 31.5%, and 2.8% patients in the IFNL4 ss469415590 TT/TT, TT/-G, and -G/-G groups, respectively. SVR rates were 82.1% or 49.3% in patients treated with peg-IFN plus ribavirin with or without telaprevir, respectively. IFNL4 ss469415590 variant and HCV viral loads or IFNL4 ss469415590 variant and early virological response were better predictors of SVR in patients treated with peg-IFN plus ribavirin with or without telaprevir, respectively. Conclusion. In the era of DAAs, measurement of IFNL4 ss469415590 variant could help the prediction of SVR in Japanese HCV genotype 1 infected individuals treated with IFN-including regimens. PMID:25548683

Evidence for 4-chlorobenzoic acid dehalogenation mediated by plasmids related to pSS50.

PubMed Central

Layton, A C; Sanseverino, J; Wallace, W; Corcoran, C; Sayler, G S

1992-01-01

The biodegradation of 4-chlorobiphenyl usually proceeds through the intermediate 4-chlorobenzoate. Few bacterial strains can degrade 4-chlorobiphenyl to 4-chlorobenzoate and 4-chlorobenzoate to CO2. This study demonstrates that the 4-chlorobiphenyl-degrading Alcaligenes sp. strain ALP83 can degrade 4-chlorobenzoate to 4-hydroxybenzoate. The dehalogenase activity is correlated with a 10-kb fragment carried on plasmid pSS70. Images PMID:1539985

13 CFR 120.348 - Amount of guarantee.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Section 120.348 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans International Trade Loans § 120.348 Amount of guarantee. SBA can guarantee up to $1,250,000... fixed-asset portion of the loan cannot exceed $1,000,000 and the non-fixed-asset portion cannot exceed...

Analysis of the Corrosion Behavior of an A-TIG Welded SS 409 Weld Fusion Zone

NASA Astrophysics Data System (ADS)

Vidyarthy, R. S.; Dwivedi, D. K.

2017-11-01

AISI 409 (SS 409) ferritic stainless steel is generally used as the thick gauge section in freight train wagons, in ocean containers, and in sugar refinery equipment. Activating the flux tungsten inert gas (A-TIG) welding process can reduce the welding cost during fabrication of thick sections. However, corrosion behavior of the A-TIG weld fusion zone is a prime concern for this type of steel. In the present work, the effect of the A-TIG welding process parameters on the corrosion behavior of a weld fusion zone made of 8-mm-thick AISI 409 ferritic stainless-steel plate has been analyzed. Potentiodynamic polarization tests were performed to evaluate the corrosion behavior. The maximum corrosion potential ( E corr) was shown by the weld made using a welding current of 215 A, a welding speed of 95 mm/min, and a flux coating density of 0.81 mg/cm2. The minimum E corr was observed in the weld made using a welding current of 190 A, a welding speed of 120 mm/min, and a flux coating density of 1.40 mg/cm2. The current study also presents the inclusive microstructure-corrosion property relationships using the collective techniques of scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffraction.

Differential biotin labelling of the cell envelope proteins in lipopolysaccharidic diderm bacteria: Exploring the proteosurfaceome of Escherichia coli using sulfo-NHS-SS-biotin and sulfo-NHS-PEG4-bismannose-SS-biotin.

PubMed

Monteiro, Ricardo; Chafsey, Ingrid; Leroy, Sabine; Chambon, Christophe; Hébraud, Michel; Livrelli, Valérie; Pizza, Mariagrazia; Pezzicoli, Alfredo; Desvaux, Mickaël

2018-06-15

Surface proteins are the major factor for the interaction between bacteria and its environment, playing an important role in infection, colonisation, virulence and adaptation. However, the study of surface proteins has proven difficult mainly due to their hydrophobicity and/or relatively low abundance compared with cytoplasmic proteins. To overcome these issues new proteomic strategies have been developed, such as cell-surface protein labelling using biotinylation reagents. Sulfo-NHS-SS-biotin is the most commonly used reagent to investigate the proteins expressed at the cell surface of various organisms but its use in lipopolysaccharidic diderm bacteria (archetypical Gram-negative bacteria) remains limited to a handful of species. While generally pass over in silence, some periplasmic proteins, but also some inner membrane lipoproteins, integral membrane proteins and cytoplasmic proteins (cytoproteins) are systematically identified following this approach. To limit cell lysis and diffusion of the sulfo-NHS-SS-biotin through the outer membrane, biotin labelling was tested over short incubation times and proved to be as efficient for 1 min at room temperature. To further limit labelling of protein located below the outer membrane, the use of high-molecular weight sulfo-NHS-PEG4-bismannose-SS-biotin appeared to recover differentially cell-envelope proteins compared to low-molecular weight sulfo-NHS-SS-biotin. Actually, the sulfo-NHS-SS-biotin recovers at a higher extent the proteins completely or partly exposed in the periplasm than sulfo-NHS-PEG4-bismannose-SS-biotin, namely periplasmic and integral membrane proteins as well as inner membrane and outer membrane lipoproteins. These results highlight that protein labelling using biotinylation reagents of different sizes provides a sophisticated and accurate way to differentially explore the cell envelope proteome of lipopolysaccharidic diderm bacteria. While generally pass over in silence, some periplasmic proteins

Surface-protein interactions on different stainless steel grades: effects of protein adsorption, surface changes and metal release.

PubMed

Hedberg, Y; Wang, X; Hedberg, J; Lundin, M; Blomberg, E; Wallinder, I Odnevall

2013-04-01

Implantation using stainless steels (SS) is an example where an understanding of protein-induced metal release from SS is important when assessing potential toxicological risks. Here, the protein-induced metal release was investigated for austenitic (AISI 304, 310, and 316L), ferritic (AISI 430), and duplex (AISI 2205) grades in a phosphate buffered saline (PBS, pH 7.4) solution containing either bovine serum albumin (BSA) or lysozyme (LSZ). The results show that both BSA and LSZ induce a significant enrichment of chromium in the surface oxide of all stainless steel grades. Both proteins induced an enhanced extent of released iron, chromium, nickel and manganese, very significant in the case of BSA (up to 40-fold increase), whereas both proteins reduced the corrosion resistance of SS, with the reverse situation for iron metal (reduced corrosion rates and reduced metal release in the presence of proteins). A full monolayer coverage is necessary to induce the effects observed.

21 CFR 348.10 - Analgesic, anesthetic, and antipruritic active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Analgesic, anesthetic, and antipruritic active ingredients. 348.10 Section 348.10 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Active Ingredients § 348.10 Analgesic, anesthetic, and antipruritic active ingredients. The active...

21 CFR 348.10 - Analgesic, anesthetic, and antipruritic active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Analgesic, anesthetic, and antipruritic active ingredients. 348.10 Section 348.10 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Active Ingredients § 348.10 Analgesic, anesthetic, and antipruritic active ingredients. The active...

21 CFR 348.10 - Analgesic, anesthetic, and antipruritic active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Analgesic, anesthetic, and antipruritic active ingredients. 348.10 Section 348.10 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Active Ingredients § 348.10 Analgesic, anesthetic, and antipruritic active ingredients. The active...

21 CFR 348.10 - Analgesic, anesthetic, and antipruritic active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Analgesic, anesthetic, and antipruritic active ingredients. 348.10 Section 348.10 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Active Ingredients § 348.10 Analgesic, anesthetic, and antipruritic active ingredients. The active...

21 CFR 348.10 - Analgesic, anesthetic, and antipruritic active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Analgesic, anesthetic, and antipruritic active ingredients. 348.10 Section 348.10 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Active Ingredients § 348.10 Analgesic, anesthetic, and antipruritic active ingredients. The active...

High temperature oxidation behavior of austenitic stainless steel AISI 304 in steam of nanofluids contain nanoparticle ZrO2

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

Prajitno, Djoko Hadi, E-mail: djokohp@batan.go.id; Syarif, Dani Gustaman, E-mail: djokohp@batan.go.id

2014-03-24

The objective of this study is to evaluate high temperature oxidation behavior of austenitic stainless steel SS 304 in steam of nanofluids contain nanoparticle ZrO{sub 2}. The oxidation was performed at high temperatures ranging from 600 to 800°C. The oxidation time was 60 minutes. After oxidation the surface of the samples was analyzed by different methods including, optical microscope, scanning electron microscope (SEM) and X-ray diffraction (XRD). X-ray diffraction examination show that the oxide scale formed during oxidation of stainless steel AISI 304 alloys is dominated by iron oxide, Fe{sub 2}O{sub 3}. Minor element such as Cr{sub 2}O{sub 3} ismore » also appeared in the diffraction pattern. Characterization by optical microscope showed that cross section microstructure of stainless steel changed after oxidized with the oxide scale on the surface stainless steels. SEM and x-ray diffraction examination show that the oxide of ZrO{sub 2} appeared on the surface of stainless steel. Kinetic rate of oxidation of austenite stainless steel AISI 304 showed that increasing oxidation temperature and time will increase oxidation rate.« less

A Puzzling Object - V348-SAGITTARIUS

NASA Astrophysics Data System (ADS)

Houziaux, L.

1983-09-01

V 348 Sagitarii is one of the many variables discovered by Miss Ida Woods on Harvard plates (Harvard Bulletin 838, 1926). Later, in the 1950s, 500 patrol plates have been scrutinized by Mrs. Jean Haies Anderson (Hoffleit, Astronomical Journal, 63, 78, 1958) at Maria Mitchell Observatory. This material covered the period 1906-1939 and the derived light Curve suggested a semi-regular variability with cycles of 200 to 400 days. Because of the resemblance of its light curve with the ones of stars undergoing at irregular intervals sudden drops of brightness before recovering more slowly their previous magnitude, that star was once classified as belonging to the R Coronae Borealis type by Schjan, who rediscovered the star in 1929 and gave it the number 3976 in the H(amburg) V(ariables) catalogue (Astronomische Nachrichten, 235, 417, 1929). V 348 Sgr, however, is seen more often at minimum light than at maximum, contrarily to the R Coronae Borealis stars. These objects are known to be carbon rich and this is indeed the case for V 348 Sgr; however, as shown first by George Herbig (Astrophysical Journal, 127, 312, 1958) the spectrum, unlike the other stars of the type reveals the presence of a hot diluted atmosphere around the star where many lines of ionized atoms of carbon are seen instead of absorption bands due to molecular compounds. So both by its light curve and by its spectrum V 348 Sgr is indeed a peculiar object.

A New Continuous Cooling Transformation Diagram for AISI M4 High-Speed Tool Steel

NASA Astrophysics Data System (ADS)

Briki, Jalel; Ben Slima, Souad

2008-12-01

The increasing evolution of dilatometric techniques now allows for the identification of structural transformations with very low signal. The use of dilatometric techniques coupled with more common techniques, such as metallographic, hardness testing, and x-ray diffraction allows to plot a new CCT diagram for AISI M4 high-speed tool steel. This diagram is useful for a better selection of alternate solutions, hardening, and tempering heat treatments. More accurate determination of the various fields of transformation of austenite during its cooling was made. The precipitation of carbides highlighted at high temperature is at the origin of the martrensitic transformation into two stages (splitting phenomena). For slow cooling rates, it was possible to highlight the ferritic, pearlitic, and bainitic transformation.

42 CFR 486.348 - Condition: Quality assessment and performance improvement (QAPI).

Code of Federal Regulations, 2010 CFR

2010-10-01

... improvement (QAPI). 486.348 Section 486.348 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT... Coverage: Organ Procurement Organizations Organ Procurement Organization Process Performance Measures § 486.348 Condition: Quality assessment and performance improvement (QAPI). The OPO must develop, implement...

Performance Testing of Twist Drills on AISI 4140 Alloy Steel

DTIC Science & Technology

1979-07-01

AISI 4140 Annealed, RPM: 110, Feed Rate: 0.005 Ipr 2^ vi 1 LIST OF FIGURES (cont.) Figure Page 20. Maximum Height of Built-up Edge at Various...period. This investigation was conducted using only one kind of work material, AISI 4140 steel, annealed. The drill used for this investigation was a...HSS (M7), 0.5 inch diameter regular point, taper shank. AISI 4140 steel, annealed, belongs to a group of high strength materials relatively hard to

Effect of Thermomechanical Treatment on the Microstructure and Mechanical Properties of AISI 52100 Steel.

DTIC Science & Technology

1981-06-01

ofJue18 AISI 52100 Steel S. PERFOMING 04G. REOR "idMeRf 7. AUTHOR(e, A. CONTRACT ON GRANT NUmetta~s) Clarence W. Schultz S. P9m1FOMuNGw ORGMSIZATION...SUPPLEMENTARY NOTCS to. 14 IV WORDS (Cominu. -s bree coer It arneemp aE~ndt bay .4*l ONber) 52100 Steel , thermomechanical processing; heat treatment...AISI 52100 steel have been investigated using a canbination of optical and transmission electron microscopy in conjunction with standard mechanical

Corrosion and wear behaviors of boronized AISI 316L stainless steel

NASA Astrophysics Data System (ADS)

Kayali, Yusuf; Büyüksaǧiş, Aysel; Yalçin, Yılmaz

2013-09-01

In this study, the effects of a boronizing treatment on the corrosion and wear behaviors of AISI 316L austenitic stainless steel (AISI 316L) were examined. The corrosion behavior of the boronized samples was studied via electrochemical methods in a simulation body fluid (SBF) and the wear behavior was examined using the ball-on-disk wear method. It was observed that the boride layer that formed on the AISI 316L surface had a flat and smooth morphology. Furthermore, X-ray diffraction analyses show that the boride layer contained FeB, Fe2B, CrB, Cr2B, NiB, and Ni2B phases. Boride layer thickness increased with an increasing boronizing temperature and time. The boronizing treatment also increased the surface hardness of the AISI 316L. Although there was no positive effect of the coating on the corrosion resistance in the SBF medium. Furthermore, a decrease in the friction coefficient was recorded for the boronized AISI 316L. As the boronizing temperature increased, the wear rate decreased in both dry and wet mediums. As a result, the boronizing treatment contributed positively to the wear resistance by increasing the surface hardness and by decreasing the friction coefficient of the AISI 316L.

Strain-induced phase transformation at the surface of an AISI-304 stainless steel irradiated to 4.4 dpa and deformed to 0.8% strain

NASA Astrophysics Data System (ADS)

Gussev, M. N.; Field, K. G.; Busby, J. T.

2014-03-01

Surface relief due to localized deformation in a 4.4-dpa neutron-irradiated AISI 304 stainless steel was investigated using scanning electron microscopy coupled with electron backscattering diffraction and scanning transmission electron microscopy. It was found a body-centered-cubic (BCC) phase (deformation-induced martensite) had formed at the surface of the deformed specimen along the steps generated from dislocation channels. Martensitic hill-like formations with widths of ˜1 μm and depths of several microns were observed at channels with heights greater than ˜150 nm above the original surface. Martensite at dislocation channels was observed in grains along the [0 0 1]-[1 1 1] orientation but not in those along the [1 0 1] orientation.

Corrosion Performance of Stainless Steels in a Simulated Launch Environment

NASA Technical Reports Server (NTRS)

Calle, Luz Marina; Vinje, Rubiela D.; MacDowell, Louis

2004-01-01

At the Kennedy Space Center, NASA relies on stainless steel (SS) tubing to supply the gases and fluids required to launch the Space Shuttle. 300 series SS tubing has been used for decades but the highly corrosive environment at the launch pad has proven to be detrimental to these alloys. An upgrade with higher alloy content materials has become necessary in order to provide a safer and long lasting launch facility. In the effort to find the most suitable material to replace the existing AISI 304L SS ([iNS S30403) and AISI 316L SS (UNS S31603) shuttle tubing, a study involving atmospheric exposure at the corrosion test site near the launch pads and electrochemical measurements is being conducted. This paper presents the results of an investigation in which stainless steels of the 300 series, 304L, 316L, and AISI 317L SS (UNS S31703) as well as highly alloyed stainless steels 254-SMO (UNS S32154), AL-6XN (N08367) and AL29-4C ([iNS S44735) were evaluated using direct current (DC) electrochemical techniques under conditions designed to simulate those found at the Space Shuttle Launch pad. The electrochemical results were compared to the atmospheric exposure data and evaluated for their ability to predict the long-term corrosion performance of the alloys.

40 CFR 35.348 - Award limitation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... ASSISTANCE Environmental Program Grants Pollution Prevention State Grants (section 6605) § 35.348 Award limitation. If a State includes a Pollution Prevention State Grant in a Performance Partnership Grant, the...

7 CFR 51.348 - One variety.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND THE EGG PRODUCTS INSPECTION ACT FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1 2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples for Processing Definitions § 51.348...

7 CFR 51.348 - One variety.

Code of Federal Regulations, 2011 CFR

2011-01-01

... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples for Processing Definitions § 51.348 One variety. One variety within the...

7 CFR 51.348 - One variety.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND THE EGG PRODUCTS INSPECTION ACT FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples for Processing Definitions § 51.348...

7 CFR 51.348 - One variety.

Code of Federal Regulations, 2012 CFR

2012-01-01

... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples for Processing Definitions § 51.348 One variety. One variety within the...

18 CFR 348.1 - Content of application for a market power determination.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Content of application for a market power determination. 348.1 Section 348.1 Conservation of Power and Water Resources... OIL PIPELINE APPLICATIONS FOR MARKET POWER DETERMINATIONS § 348.1 Content of application for a market...

42 CFR 34.8 - Reexamination; convening of review boards; expert witnesses; reports.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Reexamination; convening of review boards; expert witnesses; reports. 34.8 Section 34.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND EXAMINATIONS MEDICAL EXAMINATION OF ALIENS § 34.8 Reexamination; convening of review boards; expert witnesses; reports...

42 CFR 34.8 - Reexamination; convening of review boards; expert witnesses; reports.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 1 2014-10-01 2014-10-01 false Reexamination; convening of review boards; expert witnesses; reports. 34.8 Section 34.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND EXAMINATIONS MEDICAL EXAMINATION OF ALIENS § 34.8 Reexamination; convening of review boards; expert witnesses; reports...

40 CFR 98.348 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... GREENHOUSE GAS REPORTING Municipal Solid Waste Landfills § 98.348 Definitions. Except as specified in this... contained in landfill gas. Industrial waste landfill means any landfill other than a municipal solid waste... capacity means the maximum amount of solid waste a landfill can accept. For the purposes of this subpart...

Novel water-air circulation quenching process for AISI 4140 steel

NASA Astrophysics Data System (ADS)

Zheng, Liyun; Zheng, Dawei; Zhao, Lixin; Wang, Lihui; Zhang, Kai

2013-11-01

AISI 4140 steel is usually used after quenching and tempering. During the heat treatment process in industry production, there are some problems, such as quenching cracks, related to water-cooling and low hardness due to oil quenching. A water-air circulation quenching process can solve the problems of quenching cracks with water and the high cost quenching with oil, which is flammable, unsafe and not enough to obtain the required hardness. The control of the water-cooling and air-cooling time is a key factor in the process. This paper focuses on the quenching temperature, water-air cycle time and cycle index to prevent cracking for AISI 4140 steel. The optimum heat treatment parameters to achieve a good match of the strength and toughness of AISI 4140 steel were obtained by repeated adjustment of the water-air circulation quenching process parameters. The tensile strength, Charpy impact energy at -10 °C and hardness of the heat treated AISI 4140 steel after quenching and tempering were approximately 1098 MPa, 67.5 J and 316 HB, respectively.

40 CFR 98.348 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., turbine, internal combustion engine, or any other combustion unit used to destroy or oxidize methane... GREENHOUSE GAS REPORTING Municipal Solid Waste Landfills § 98.348 Definitions. Except as specified in this section, all terms used in this subpart have the same meaning given in the Clean Air Act and subpart A of...

40 CFR 98.348 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., turbine, internal combustion engine, or any other combustion unit used to destroy or oxidize methane... GREENHOUSE GAS REPORTING Municipal Solid Waste Landfills § 98.348 Definitions. Except as specified in this section, all terms used in this subpart have the same meaning given in the Clean Air Act and subpart A of...

42 CFR 413.348 - Limitation on review.

Code of Federal Regulations, 2010 CFR

2010-10-01

...; OPTIONAL PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.348 Limitation on review. Judicial or administrative review under...

42 CFR 413.348 - Limitation on review.

Code of Federal Regulations, 2013 CFR

2013-10-01

...; OPTIONAL PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.348 Limitation on review. Judicial or administrative review under...

40 CFR 35.348 - Award limitation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Environmental Program Grants Pollution Prevention State Grants (section 6605) § 35.348 Award limitation. If a State includes a Pollution Prevention State Grant in a Performance Partnership Grant, the...

40 CFR 35.348 - Award limitation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Environmental Program Grants Pollution Prevention State Grants (section 6605) § 35.348 Award limitation. If a State includes a Pollution Prevention State Grant in a Performance Partnership Grant, the...

49 CFR 178.348 - Specification DOT 412; cargo tank motor vehicle.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Specification DOT 412; cargo tank motor vehicle. 178.348 Section 178.348 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

Type-IVC Secretion System: A Novel Subclass of Type IV Secretion System (T4SS) Common Existing in Gram-Positive Genus Streptococcus

PubMed Central

Chen, Chen; Gao, George F.

2012-01-01

A growing number of pathogens are being found to possess specialized secretion systems which they use in various ways to subvert host defenses. Type IV secretion system (T4SS) is one of versatile secretion systems essential for the virulence and even survival of some bacteria species, and they enable the secretion of protein and DNA substrates across the cell envelope. T4SS was once believed to be present only in Gram-negative bacteria. In this study, we present evidence of a new subclass of T4SS, Type-IVC secretion system and indicate its common existence in the Gram-positive bacterial genus Streptococcus. We further identified that VirB1, VirB4, VirB6 and VirD4 are the minimal key components of this system. Using genome comparisons and evolutionary relationship analysis, we proposed that Type-IVC secretion system is movable via transposon factors and mediates the conjugative transfer of DNA, enhances bacterial pathogenicity, and could cause large-scale outbreaks of infections in humans. PMID:23056296

Analysis of AISI 304 Tensile Strength as an Anchor Chain of Mooring System

NASA Astrophysics Data System (ADS)

Hamidah, I.; Wati, R.; Hamdani, R. A.

2018-05-01

The background of this research is the use of mild steel (i.e., St37) as anchor chain that works on the corrosive environment of seawater which is possible to decrease its tensile strength. The longer soaked in seawater, the more significant the lowering of its tensile strength. Anchor chain needs to be designed by considering its tensile strength and corrosion resistance, so it’s able to support mooring system well. The primary purpose of this research is obtaining the decreasing of stainless steel 304 (AISI 304) tensile strength which is corroded by seawater as anchor chain of the mooring system. It is also essential to obtain the lifetime of AISI304 and St37 as anchor chain with the same load, the corrosion rate of AISI 304, and St 37 in seawater. The method which was employed in this research is an experiment with four pieces of stainless steel AISI 304, and of St 37 corrosion testing samples, six pieces of stainless steel 304, and six pieces of St 37 for tensile testing samples. The result of this research shows that seawater caused stainless steel AISI 304 as anchor chain has decreased of tensile strength about 1.68 % during four weeks. Also, it indicates that AISI 304 as anchor chain has a lifetime about 130 times longer than St 37. Further, we found that the corrosion rate of stainless steel 304 in seawater is 0.2042 mpy in outstanding category, while the St 37 samples reached up to 27.0247 mpy ranked as fair category. This result recommends that AISI 304 more excellence than St 37 as anchor chain of the mooring system.

Materials screening tests for the krypton-85 storage development program

NASA Astrophysics Data System (ADS)

Nagata, P. K.

1981-04-01

The results of a materials testing program for krypton-85 storage techniques are reported. Corrosion and stress corrosion tests were performed on a variety of materials including AISI 4130, Type 316 SS, Type 304 SS, Type 310 SS, Nitronic 50, and alloy A286. Test environments were high-purity liquid rubidium, liquid rubidium contaminated with oxygen, and rubidium hydroxide. Oxygen and water contaminations in liquid rubidium were found to greatly increase both general and localized corrosion of the materials tested. Alloy A286, Type 304 SS, and AISI 4130 were eliminated as candidate materials due to their susceptibility to general corrosion and stress corrosion cracking.

A Life Study of Ausforged, Standard Forged and Standard Machined AISI M-50 Spur Gears

NASA Technical Reports Server (NTRS)

Townsend, D. P.; Bamberger, E. N.; Zaretsky, E. V.

1975-01-01

Tests were conducted at 350 K (170 F) with three groups of 8.9 cm (3.5 in.) pitch diameter spur gears made of vacuum induction melted (VIM) consumable-electrode vacuum-arc melted (VAR), AISI M-50 steel and one group of vacuum-arc remelted (VAR) AISI 9310 steel. The pitting fatigue life of the standard forged and ausforged gears was approximately five times that of the VAR AISI 9310 gears and ten times that of the bending fatigue life of the standard machined VIM-VAR AISI M-50 gears run under identical conditions. There was a slight decrease in the 10-percent life of the ausforged gears from that for the standard forged gears, but the difference is not statistically significant. The standard machined gears failed primarily by gear tooth fracture while the forged and ausforged VIM-VAR AISI M-50 and the VAR AISI 9310 gears failed primarily by surface pitting fatigue. The ausforged gears had a slightly greater tendency to fail by tooth fracture than the standard forged gears.

Rolling Contact Fatigue Life and Spall Propagation Characteristics of AISI M50, M50 NiL, and AISI 52100. Part 3. Metallurgical Examination (Preprint)

DTIC Science & Technology

2009-10-01

bearing materials, namely AISI 52100, VIM-VAR M50 , and VIM-VAR M50 NiL steels . While...propagation characteristics of three bearing materials, namely AISI 52100, VIM-VAR M50 , and VIM-VAR M50 NiL steels . While there is substantial prior work...deformation from run in. Residual stress profiles for bearing 075B are shown in Figure 3. The bearing is made from M50 steel and the spall

40 CFR 761.348 - Contemporaneous sampling.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for Off-Site Disposal... Section 761.348 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES...

40 CFR 761.348 - Contemporaneous sampling.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for Off-Site Disposal... Section 761.348 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES...

40 CFR 761.348 - Contemporaneous sampling.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for Off-Site Disposal... Section 761.348 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES...

Dynamical histories of the IC 348 and NGC 1333 star-forming regions in Perseus

NASA Astrophysics Data System (ADS)

Parker, Richard J.; Alves de Oliveira, Catarina

2017-07-01

We present analyses of the spatial distributions of stars in the young (1-3 Myr) star-forming regions IC 348 and NGC 1333 in the Perseus giant molecular cloud. We quantify the spatial structure using the Q-parameter and find that both IC 348 and NGC 1333 are smooth and centrally concentrated with Q-parameters of 0.98 and 0.89, respectively. Neither region exhibits mass segregation (Λ _MSR = 1.1^{+0.2}_{-0.3} for IC 348 and Λ _MSR = 1.2^{+0.4}_{-0.3} for NGC 1333, where ΛMSR ˜ 1 corresponds to no mass segregation) nor do the most massive stars reside in areas of enhanced stellar surface density compared to the average surface density, according to the ΣLDR method. We then constrain the dynamical histories and hence initial conditions of both regions by comparing the observed values to N-body simulations at appropriate ages. Stars in both regions likely formed with subvirial velocities that contributed to merging of substructure and the formation of smooth clusters. The initial stellar densities were no higher than ρ ˜ 100-500 M⊙ pc-3 for IC 348 and ρ ˜ 500-2000 M⊙ pc-3 for NGC 1333. These initial densities, in particular that of NGC 1333, are high enough to facilitate dynamical interactions that would likely affect ˜10 per cent of protoplanetary discs and binary stars.

Surface fatigue life of M50NiL and AISI 9310 spur gears and R C bars

NASA Technical Reports Server (NTRS)

Townsend, Dennis P.; Bamberger, Eric N.

1991-01-01

Spur gear endurance tests and rolling element surface fatigue tests were conducted to study vacuum induction melted, vacuum arc remelted (VIM-VAR) M50NiL steel for use as a gear steel in advanced aircraft applications, to determine its endurance characteristics, and to compare the results with those for standard VAR and VIM-VAR AISI 9310 gear material. Tests were conducted with spur gears and rolling contact bars manufactured from VIM-VAR M50NiL and VAR and VIM-VAR AISI 9310. The gear pitch diameter was 8.9 cm. Gear test conditions were an inlet oil temperature of 320 K, and outlet oil temperature of 350 K, a maximum Hertz stress of 1.71 GPa, and a speed of 10000 rpm. Bench rolling element fatigue tests were conducted at ambient temperatures with a bar speed of 12,500 rpm and a maximum Hertz stress of 4.83 GPa. The VIM-VAR M50NiL gears had a surface fatigue life that was 4.5 and 11.5 times that for VIM-VAR and VAR AISI 9310 gears, respectively. The surface fatigue life of the VIM-VAR M50NiL rolling contact bars was 13.2 and 21.6 times that for the VIM-VAR and VAR AISI 9310, respectively. The VIM-VAR M50NiL material was shown to have good resistance to fracture through a fatigue spall and superior fatigue life to both other gears.

36 CFR 34.8 - Preservation of natural, cultural and archeological resources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Preservation of natural, cultural and archeological resources. 34.8 Section 34.8 Parks, Forests, and Public Property NATIONAL PARK... natural, cultural and archeological resources. In addition to the provisions of § 2.1 of this chapter, the...

40 CFR 761.348 - Contemporaneous sampling.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Contemporaneous sampling. 761.348... PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for Off-Site Disposal...

40 CFR 761.348 - Contemporaneous sampling.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Contemporaneous sampling. 761.348... PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for Off-Site Disposal...

Kinetics and Tribological Characterization of Pack-Borided AISI 1025 Steel

NASA Astrophysics Data System (ADS)

Gómez-Vargas, O. A.; Keddam, M.; Ortiz-Domínguez, M.

2017-03-01

In this present study, the AISI 1025 steel was pack-borided in the temperature range of 1,123-1,273 K for different treatment times ranging from 2 to 8 h. A diffusion model was suggested to estimate the boron diffusion coefficients in the Fe2B layers. As a result, the boron activation energy for the AISI 1025 steel was estimated as 174.36 kJ/mol. This value of energy was compared with the literature data. To extend the validity of the present model, other additional boriding conditions were considered. The boride layers formed on the AISI 1025 steel were characterized by the following experimental techniques: scanning electron microscopy, X-ray diffraction analysis and the Daimler-Benz Rockwell-C indentation technique. Finally, the scratch and pin-on-disc tests for wear resistance were achieved using an LG Motion Ltd and a CSM tribometer, respectively, under dry sliding conditions.

Hardness of AISI type 410 martensitic steels after high temperature irradiation via nanoindentation

NASA Astrophysics Data System (ADS)

Waseem, Owais Ahmed; Jeong, Jong-Ryul; Park, Byong-Guk; Maeng, Cheol-Soo; Lee, Myoung-Goo; Ryu, Ho Jin

2017-11-01

The hardness of irradiated AISI type 410 martensitic steel, which is utilized in structural and magnetic components of nuclear power plants, is investigated in this study. Proton irradiation of AISI type 410 martensitic steel samples was carried out by exposing the samples to 3 MeV protons up to a 1.0 × 1017 p/cm2 fluence level at a representative nuclear reactor coolant temperature of 350 °C. The assessment of deleterious effects of irradiation on the micro-structure and mechanical behavior of the AISI type 410 martensitic steel samples via transmission electron microscopy-energy dispersive spectroscopy and cross-sectional nano-indentation showed no significant variation in the microscopic or mechanical characteristics. These results ensure the integrity of the structural and magnetic components of nuclear reactors made of AISI type 410 martensitic steel under high-temperature irradiation damage levels up to approximately 5.2 × 10-3 dpa.

An experimental analysis of process parameters to manufacture micro-channels in AISI H13 tempered steel by laser micro-milling

NASA Astrophysics Data System (ADS)

Teixidor, D.; Ferrer, I.; Ciurana, J.

2012-04-01

This paper reports the characterization of laser machining (milling) process to manufacture micro-channels in order to understand the incidence of process parameters on the final features. Selection of process operational parameters is highly critical for successful laser micromachining. A set of designed experiments is carried out in a pulsed Nd:YAG laser system using AISI H13 hardened tool steel as work material. Several micro-channels have been manufactured as micro-mold cavities varying parameters such as scanning speed (SS), pulse intensity (PI) and pulse frequency (PF). Results are obtained by evaluating the dimensions and the surface finish of the micro-channel. The dimensions and shape of the micro-channels produced with laser-micro-milling process exhibit variations. In general the use of low scanning speeds increases the quality of the feature in both surface finishing and dimensional.

A comprehensive review on cold work of AISI D2 tool steel

NASA Astrophysics Data System (ADS)

Abdul Rahim, Mohd Aidil Shah bin; Minhat, Mohamad bin; Hussein, Nur Izan Syahriah Binti; Salleh, Mohd Shukor bin

2017-11-01

As a common material in mould and die application, AISI D2 cold work tool steel has proven to be a promising chosen material in the industries. However, challenges remain in using AISI D2 through a modified version with a considerable progress having been made in recent years. This paper provides a critical review of the original as-cast AISI D2 cold work tool steel up to the modified version. The main purpose is to develop an understanding of current modified tool steel trend; the machinability of AISI D2 (drilling, milling, turning, grinding and EDM/WEDM; and the microstructure evolution and mechanical properties of these cold work tool steels due to the presence of alloy materials in the steel matrix. The doping of rare earth alloy element, new steel fabrication processes, significant process parameter in machinability and surface treatment shows that there have been few empirical investigations into these cold work tool steel alloys. This study has discovered that cold work tool steel will remain to be explored in order to survive in the steel industries.

Development Specification for RV-346/348 Positive Pressure Relief Valves (PPRV)

NASA Technical Reports Server (NTRS)

Ralston, Russell L.

2017-01-01

This specification establishes the requirements for design, performance, safety, testing, and manufacture of the RV-346 and RV-348, Positive Pressure Relief Valve (PPRV) as part of the Advanced Extravehicular Mobility Unit (EMU)(AEMU) Portable Life Support System (PLSS). The RV-346 serves as the Positive Pressure Relief Valve (PPRV), and the RV-348 serves as the Secondary Positive Pressure Relief Valve (SPPRV).

Meeting the complex needs of urban youth and their families through the 4Rs 2Ss Family Strengthening Program: The "real world" meets evidence-informed care.

PubMed

Small, Latoya; Jackson, Jerrold; Gopalan, Geetha; McKay, Mary McKernan

2015-07-01

Youth living in poverty face compounding familial and environmental challenges in utilizing effective community mental health services. They have ongoing stressors that increase their dropout rate in mental health service use. Difficulties also exist in staying engaged in services when they are involved with the child welfare system. This study examines the 4Rs 2Ss Family Strengthening Program, developed across four broad conceptual categories related to parenting skills and family processes that form a multiple family group service delivery approach. A total of 321 families were enrolled in this randomized intervention study, assigned to either the 4Rs 2Ss Family Strengthening Program or standard care services. Caregivers and their children randomly assigned to the experimental condition received a 16 week multiple family group intervention through their respective outpatient community mental health clinic. Data was collected at baseline, midtest (8 weeks), posttest (16 weeks), and 6 month follow-up. Major findings include high engagement in the 4Rs 2Ss Family Strengthening Program, compared to standard services. Although child welfare status is not related to attendance, family stress and parental depression are also related to participant engagement in this multiple family group intervention. Involvement in the 4Rs 2Ss Family Strengthening Program resulted in improved effects for child behaviors. Lastly, no evidence of moderation effects on family stress, child welfare involvement, or parental needs were found. The 4Rs 2Ss Family Strengthening Program appeared able to engage families with more complex "real world" needs.

Surface fatigue life and failure characteristics of EX-53, CBS 1000M, and AISI 9310 gear materials

NASA Technical Reports Server (NTRS)

Townsend, D. P.

1985-01-01

Spur gear endurance tests and rolling-element surface fatigue tests are conducted to investigate EX-53 and CBS 1000M steels for use as advanced application gear materials, to determine their endurance characteristics, and to compare the results with the standard AISI 9310 gear material. The gear pitch diameter is 8.89 cm (3.50 in). Gear test conditions are an oil inlet temperature of 320 K (116 F), an oil outlet temperature of 350 K (170 F), a maximum Hertz stress of 1.71 GPa (248 ksi), and a speed of 10,000 rpm. Bench-type rolling-element fatigue tests are conducted at ambient temperature with a bar specimen speed of 12,500 rpm and a maximum Hertz stress of 4.83 GPa (700 ksi). The EX-53 test gears have a surface fatigue life of twice that of the AISI 9310 spur gears. The CBS 1000M test gears have a surface fatigue life of more than twice that of the AISI 9310 spur gears. However, the CBS 1000M gears experience a 30-percent tooth fracture failure which limits its use as a gear material. The rolling-contact fatigue lines of RC bar specimens of EX-53 and ASISI 9310 are approximately equal. However, the CBS 1000M RC specimens have a surface fatigue life of about 50 percent that of the AISI 9310.

RXTE Observations of the Seyfert 2 Galaxy MrK 348

NASA Technical Reports Server (NTRS)

Smith, David A.; Georgantopoulos, Ioannis; Warwick, Robert S.

2000-01-01

We present RXTE monitoring observations of the Seyfert 2 galaxy Mrk 348 spanning a 6 month period. The time-averaged spectrum in the 3-20 keV band shows many features characteristic of a Compton-thin Seyfert 2 galaxy, namely a hard underlying power-law continuum (Gamma approximately equal 1.8) with heavy soft X-ray absorption (N(sub H) approximately 10(exp 23)/sq cm) plus measurable iron K.alpha emission (equivalent width approximately 100 eV) and, at high energy, evidence for a reflection component (R approximately < 1). During the first half of the monitoring period the X-ray continuum flux from Mrk 348 remained relatively steady. However this was followed by a significant brightening of the source (by roughly a factor of 4) with the fastest change corresponding to a doubling of its X-ray flux on a timescale of about 20 days. The flux increase was accompanied by a marked softening of X-ray spectrum most likely attributable to a factor approximately 3 decline in the intrinsic line-of-sight column density. In contrast the iron K.alpha line and the reflection components showed no evidence of variability. These observations suggest a scenario in which the central X-ray source is surrounded by a patchy distribution of absorbing material located within about a light-week of the nucleus of Mrk 348. The random movement of individual clouds within the absorbing screen, across our line of sight, produces substantial temporal variations in the measured column density on timescales of weeks to months and gives rise to the observed X-ray spectral variability. However, as viewed from the nucleus the global coverage and typical thickness of the cloud layer remains relatively constant.

32 CFR 644.348 - Delegation of authority to division and district engineers.

Code of Federal Regulations, 2013 CFR

2013-07-01

... engineers. 644.348 Section 644.348 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Departments of the Army and Air Force to report excess real and related personal property to GSA in accordance... needs of the Department of Defense, in accordance with §§ 644.333 through 644.339, and has been cleared...

32 CFR 644.348 - Delegation of authority to division and district engineers.

Code of Federal Regulations, 2014 CFR

2014-07-01

... engineers. 644.348 Section 644.348 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Departments of the Army and Air Force to report excess real and related personal property to GSA in accordance... needs of the Department of Defense, in accordance with §§ 644.333 through 644.339, and has been cleared...

32 CFR 644.348 - Delegation of authority to division and district engineers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... engineers. 644.348 Section 644.348 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Departments of the Army and Air Force to report excess real and related personal property to GSA in accordance... needs of the Department of Defense, in accordance with §§ 644.333 through 644.339, and has been cleared...

32 CFR 644.348 - Delegation of authority to division and district engineers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... engineers. 644.348 Section 644.348 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Departments of the Army and Air Force to report excess real and related personal property to GSA in accordance... needs of the Department of Defense, in accordance with §§ 644.333 through 644.339, and has been cleared...

32 CFR 644.348 - Delegation of authority to division and district engineers.

Code of Federal Regulations, 2012 CFR

2012-07-01

... engineers. 644.348 Section 644.348 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY... Departments of the Army and Air Force to report excess real and related personal property to GSA in accordance... needs of the Department of Defense, in accordance with §§ 644.333 through 644.339, and has been cleared...

20 CFR 702.348 - Formal hearings; preparation of final decision and order; content.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Formal hearings; preparation of final decision and order; content. 702.348 Section 702.348 Employees' Benefits EMPLOYMENT STANDARDS... final decision and order; content. Within 20 days after the official termination of the hearing as...

Atomic diffusion in laser surface modified AISI H13 steel

NASA Astrophysics Data System (ADS)

Aqida, S. N.; Brabazon, D.; Naher, S.

2013-07-01

This paper presents a laser surface modification process of AISI H13 steel using 0.09 and 0.4 mm of laser spot sizes with an aim to increase surface hardness and investigate elements diffusion in laser modified surface. A Rofin DC-015 diffusion-cooled CO2 slab laser was used to process AISI H13 steel samples. Samples of 10 mm diameter were sectioned to 100 mm length in order to process a predefined circumferential area. The parameters selected for examination were laser peak power, pulse repetition frequency (PRF), and overlap percentage. The hardness properties were tested at 981 mN force. Metallographic study and energy dispersive X-ray spectroscopy (EDXS) were performed to observe presence of elements and their distribution in the sample surface. Maximum hardness achieved in the modified surface was 1017 HV0.1. Change of elements composition in the modified layer region was detected in the laser modified samples. Diffusion possibly occurred for C, Cr, Cu, Ni, and S elements. The potential found for increase in surface hardness represents an important method to sustain tooling life. The EDXS findings signify understanding of processing parameters effect on the modified surface composition.

49 CFR 178.348-1 - General requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Specifications for Containers for Motor Vehicle Transportation § 178.348-1 General requirements. (a) Each specification DOT 412 cargo tank motor vehicle must conform to the general design and construction requirements in § 178.345 in addition to the specific requirements of this section. (b) The MAWP of each cargo...

Experimental study on joining of AA6063 and AISI 1040 steel

NASA Astrophysics Data System (ADS)

Hynes, N. Rajesh Jesudoss; Raja, S.

2018-05-01

Feasibility of joining of dissimilar metals with different physical, chemical and thermal properties such as AA6063 alloy and AISI 1040 steel is worthwhile study, since it has tremendous applications in all most of all engineering domains. The mechanism of bonding is studied using scanning electron microscopy. Impact strength of AA2024/AISI joints, axial shortening distance, micro hardness distribution and joint strength are determined. Micro hardness profile shows increased hardness value at the joint interface, due to grain refinement.

43 CFR 34.8 - Affirmative action plans.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Affirmative action plans. 34.8 Section 34..., applicants or recipients shall have an acceptable affirmative action plan which has been approved by the... paragraph (c) of this section. The affirmative action plan must set forth overall goals and timetables for...

49 CFR 178.348-1 - General requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Containers for Motor Vehicle Transportation § 178.348-1 General requirements. (a) Each specification DOT 412 cargo tank motor vehicle must conform to the general design and construction requirements in § 178.345 in addition to the specific requirements of this section. (b) The MAWP of each cargo tank must be at...

49 CFR 178.348-1 - General requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Containers for Motor Vehicle Transportation § 178.348-1 General requirements. (a) Each specification DOT 412 cargo tank motor vehicle must conform to the general design and construction requirements in § 178.345 in addition to the specific requirements of this section. (b) The MAWP of each cargo tank must be at...

49 CFR 178.348-1 - General requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Containers for Motor Vehicle Transportation § 178.348-1 General requirements. (a) Each specification DOT 412 cargo tank motor vehicle must conform to the general design and construction requirements in § 178.345 in addition to the specific requirements of this section. (b) The MAWP of each cargo tank must be at...

49 CFR 178.348-1 - General requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Containers for Motor Vehicle Transportation § 178.348-1 General requirements. (a) Each specification DOT 412 cargo tank motor vehicle must conform to the general design and construction requirements in § 178.345 in addition to the specific requirements of this section. (b) The MAWP of each cargo tank must be at...

SS-mPMG and SS-GA: tools for finding pathways and dynamic simulation of metabolic networks.

PubMed

Katsuragi, Tetsuo; Ono, Naoaki; Yasumoto, Keiichi; Altaf-Ul-Amin, Md; Hirai, Masami Y; Sriyudthsak, Kansuporn; Sawada, Yuji; Yamashita, Yui; Chiba, Yukako; Onouchi, Hitoshi; Fujiwara, Toru; Naito, Satoshi; Shiraishi, Fumihide; Kanaya, Shigehiko

2013-05-01

Metabolomics analysis tools can provide quantitative information on the concentration of metabolites in an organism. In this paper, we propose the minimum pathway model generator tool for simulating the dynamics of metabolite concentrations (SS-mPMG) and a tool for parameter estimation by genetic algorithm (SS-GA). SS-mPMG can extract a subsystem of the metabolic network from the genome-scale pathway maps to reduce the complexity of the simulation model and automatically construct a dynamic simulator to evaluate the experimentally observed behavior of metabolites. Using this tool, we show that stochastic simulation can reproduce experimentally observed dynamics of amino acid biosynthesis in Arabidopsis thaliana. In this simulation, SS-mPMG extracts the metabolic network subsystem from published databases. The parameters needed for the simulation are determined using a genetic algorithm to fit the simulation results to the experimental data. We expect that SS-mPMG and SS-GA will help researchers to create relevant metabolic networks and carry out simulations of metabolic reactions derived from metabolomics data.

Meeting the complex needs of urban youth and their families through the 4Rs 2Ss Family Strengthening Program: The “real world” meets evidence-informed care

PubMed Central

Small, Latoya; Jackson, Jerrold; Gopalan, Geetha; McKay, Mary McKernan

2014-01-01

Youth living in poverty face compounding familial and environmental challenges in utilizing effective community mental health services. They have ongoing stressors that increase their dropout rate in mental health service use. Difficulties also exist in staying engaged in services when they are involved with the child welfare system. This study examines the 4Rs 2Ss Family Strengthening Program, developed across four broad conceptual categories related to parenting skills and family processes that form a multiple family group service delivery approach. A total of 321 families were enrolled in this randomized intervention study, assigned to either the 4Rs 2Ss Family Strengthening Program or standard care services. Caregivers and their children randomly assigned to the experimental condition received a 16 week multiple family group intervention through their respective outpatient community mental health clinic. Data was collected at baseline, midtest (8 weeks), posttest (16 weeks), and 6 month follow-up. Major findings include high engagement in the 4Rs 2Ss Family Strengthening Program, compared to standard services. Although child welfare status is not related to attendance, family stress and parental depression are also related to participant engagement in this multiple family group intervention. Involvement in the 4Rs 2Ss Family Strengthening Program resulted in improved effects for child behaviors. Lastly, no evidence of moderation effects on family stress, child welfare involvement, or parental needs were found. The 4Rs 2Ss Family Strengthening Program appeared able to engage families with more complex “real world” needs. PMID:26523115

Experimental measurement of stationary SS 304, SS 316L and 8630 GTA weld pool surface temperatures

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

Kraus, H.G.

1989-07-01

The optical spectral radiometric/laser reflectance experimental method, previously developed by the author, was extended to obtain high-resolution surface temperature maps of stationary GTA molten weld pools using thick-plate SS 304, SS316L, and 8630 steel. Increasing the welding current from 50 to 200 A resulted in peak pool surface temperatures from 1050{sup 0} to 2400{sup 0}C for the SS 304. At a constant welding current of 150 A, the SS 304 and various heats of SS 316L and 8630 resulted in peak weld pool temperatures from 2300{sup 0} to 2700{sup 0}C. Temperature contour plots of all the welds made are given.more » Surface temperature maps are classified into types that are believed to be indicative of the convective circulation patterns present in the weld pools.« less

Antibacterial and Tribological Performance of Carbonitride Coatings Doped with W, Ti, Zr, or Cr Deposited on AISI 316L Stainless Steel

PubMed Central

Yao, Sun-Hui; Su, Yen-Liang; Lai, Yu-Cheng

2017-01-01

Carbonitride (CNx) coatings have existed for several decades but are not well understood. Related studies have indicated that CNx coatings exhibit behaviors comparable to diamond-like carbon (DLC) coatings. Metal-doped CNx coatings are expected to show superior performance to single CNx coatings. In this study, a CNx coating and a group of CNx coatings with 6 at. % metal doping (W, Ti, Zr, or Cr) were prepared on biograde AISI 316L stainless steel (SS316L) substrates, and they were then characterized and studied for antibacterial and wear performance. The microstructure, constituent phase, nanohardness, adhesion, surface roughness, and contact angle were evaluated. The antimicrobial test used Staphylococcus aureus and followed the Japanese Industrial Standard JIS Z 2801:2010. Finally, the wear behavior was assessed. The results showed that the CNx coating was a composite of amorphous CNx and amorphous C structures. The metal doping caused crystalline metal carbides/nitrides to form in the CNx coatings, which weakened their overall integrity. All the coatings showed antimicrobial ability for the SS316L samples. The CNx-Zr coating, the surface of which had the highest hydrophilicity, produced the best antibacterial performance. However, the CNx-Zr coating showed lower wear resistance than the CNx-W and CNx-Ti coatings. The CNx-Ti coating with a highly hydrophilic surface exhibited the lowest antibacterial ability. PMID:29039782

CHROMIUM PLATING FOR PROTECTION AGAINST STRESS CORROSION CRACKING OF HARDENED AISI 410 STEEL

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

Suss, H.

1958-04-22

Because of its high corrosion resistance properties, chromium electroplate should offer protection to AISI 419 steel against stress corrosion cracking. Tests have been made (KAPL and Bettis) on chromium plates on test specimens as deposited by two different sources in conformance with Bettis and USMC specifications. These deposits either offered protection to hardened (RC36- 42) AISI 410 against stress corrosion cracking, or caused accelerated stress corrosion cracking under conditions which did not crack unplated material. At present there is no significant data which could give definite clues for these extreme differences in the corrosive protective values. The results of testsmore » so far strongly question tbe value of chromium plate as a means to protect AISI 410 against stress corrosion cracking. (A.C.)« less

Young Low-Mass Stars and Brown Dwarfs in IC 348

NASA Astrophysics Data System (ADS)

Luhman, K. L.

1999-11-01

I present new results from a continuing program to identify and characterize the low-mass stellar and substellar populations in the young cluster IC 348 (0.5-10 Myr). Optical spectroscopy has revealed young objects with spectral types as late as M8.25. The intrinsic J-H and H-K colors of these sources are dwarflike, whereas the R-I and I-J colors appear intermediate between the colors of dwarfs and giants. Furthermore, the spectra from 6500 to 9500 Å are reproduced well with averages of standard dwarf and giant spectra, suggesting that such averages should be used in the classification of young late-type sources. An H-R diagram is constructed for the low-mass population in IC 348 (K6-M8). The presumably coeval components of the young quadruple system GG Tau (White et al.) and the locus of stars in IC 348 are used as empirical isochrones to test the theoretical evolutionary models. The calculations of Burrows et al. do not appear to be consistent with the data at these earliest stages of stellar evolution. There is fair agreement between the data and the model isochrones of D'Antona & Mazzitelli, except near the hydrogen-burning limit. The agreement cannot be improved by changing the conversion between spectral types and effective temperatures. On the other hand, for the models of Baraffe et al., an adjustment of the temperature scale to progressively warmer temperatures at later M types, intermediate between dwarfs and giants, brings all components of GG Tau onto the same model isochrone and gives the population of IC 348 a constant age and age spread as a function of mass. When other observational constraints are considered, such as the dynamical masses of GM Aur, DM Tau, and GG Tau A, the models of Baraffe et al. are the most consistent with observations of young systems. With compatible temperature scales, the models of both D'Antona & Mazzitelli and Baraffe et al. suggest that the hydrogen-burning mass limit occurs near M6 at ages of <~10 Myr. Thus, several

Tensile and fatigue data for irradiated and unirradiated AISI 310 stainless steel and titanium - 5 percent aluminum - 2.5 percent tin: Application of the method of universal slopes

NASA Technical Reports Server (NTRS)

Debogdan, C. E.

1973-01-01

Irradiated and unirradiated tensile and fatigue specimens of AISI 310 stainless steel and Ti-5Al-2.5Sn were tested in the range of 100 to 10,000 cycles to failure to determine the applicability of the method of universal slopes to irradiated materials. Tensile data for both materials showed a decrease in ductility and increase in ultimate tensile strength due to irradiation. Irradiation caused a maximum change in fatigue life of only 15 to 20 percent for both materials. The method of universal slopes predicted all the fatigue data for the 310 SS (irradiated as well as unirradiated) within a life factor of 2. For the titanium alloy, 95 percent of the data was predicted within a life factor of 3.

Variability in response to nicotine in the LSxSS RI strains: potential role of polymorphisms in alpha4 and alpha6 nicotinic receptor genes.

PubMed

Tritto, Theresa; Stitzel, Jerry A; Marks, Michael J; Romm, Elena; Collins, Allan C

2002-04-01

Several studies have shown that genetic factors influence the effects of nicotine on respiration, acoustic startle, Y-maze crosses and rears, heart rate and body temperature in the mouse. Recently, we identified restriction fragment length polymorphisms (RFLPs) associated with the alpha4 (Chrna4) and alpha6 (Chrna6) nicotinic cholinergic receptor genes in the recombinant inbred (RI) strains derived from the Long-Sleep (LS) and Short-Sleep (SS) mouse lines. The alpha4 polymorphism has been identified as a point-mutation at position 529 (threonine to alanine) and the alpha6 polymorphism has not yet been identified. The studies described here evaluated the potential role of these polymorphisms in regulating sensitivity to nicotine by constructing dose-response curves for the effects of nicotine on six responses in the LSxSS RI strains. The results obtained suggest that both of the polymorphisms may play a role in regulating variability in sensitivity to nicotine. Those RI strains carrying the LS-like alpha4 RFLP were significantly more sensitive to the effects of nicotine on Y-maze crosses and rears, temperature and respiration and were less sensitive to the effects of nicotine on acoustic startle than those strains carrying the SS-like alpha4 RFLP. Those RI strains carrying the LS-like alpha6 RFLP were more sensitive to the effects of nicotine on respiration and acoustic startle, and less sensitive to the effects of nicotine on Y-maze crosses than those strains carrying the SS-like alpha6 RFLP. These results suggest that genetically determined differences in sensitivity to nicotine may be explained, in part, by variability associated with at least two of the neuronal nicotinic receptor genes, alpha4 and alpha6.

Effect of mechanical activation on jell boronizing treatment of the AISI 4140

NASA Astrophysics Data System (ADS)

Yılmaz, S. O.; Karataş, S.

2013-06-01

The article presents the effect of mechanical activation on the growth kinetics of boride layer of boronized AISI 4140 steel. The samples were boronized by ferroboron + (SiO2-Na2O) powders for 873-1173 K temperature and 2, 4, 6 and 8 h times, respectively. The morphology and types of borides formed on the surface of AISI 4140 steel substrate were analyzed. Layer growth kinetics were analyzed by measuring the extent of penetration of FeB and Fe2B sublayers as function of treatment time and temperature in the range of 873-1173 K. High diffusivity was obtained by creating a large number of defects through mechanical activation in the form of nanometer sized crystalline particles through the repeated fracturing and cold-welding of the powder particles, and a depth of 100 μm was found in the specimen borided by the 2 h MA powders, for 4 h and 1073 K, where 2000-2350 HV were measured. Consequently, the application conditions of boronizing were improved by usage of mechanical activation. The preferred Fe2B boride without FeB could be formed in the boride layer under 973 K boronizing temperature by mechanically activated by ferroboron + sodium silicate powder mixture due to the decrease of the activation energy.

Toolpath strategy for cutter life improvement in plunge milling of AISI H13 tool steel

NASA Astrophysics Data System (ADS)

Adesta, E. Y. T.; Avicenna; hilmy, I.; Daud, M. R. H. C.

2018-01-01

Machinability of AISI H13 tool steel is a prominent issue since the material has the characteristics of high hardenability, excellent wear resistance, and hot toughness. A method of improving cutter life of AISI H13 tool steel plunge milling by alternating the toolpath and cutting conditions is proposed. Taguchi orthogonal array with L9 (3^4) resolution will be employed with one categorical factor of toolpath strategy (TS) and three numeric factors of cutting speed (Vc), radial depth of cut (ae ), and chip load (fz ). It is expected that there are significant differences for each application of toolpath strategy and each cutting condition factor toward the cutting force and tool wear mechanism of the machining process, and medial axis transform toolpath could provide a better tool life improvement by a reduction of cutting force during machining.

20 CFR 348.2 - Recognition by the Board of a person to act in behalf of another.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Recognition by the Board of a person to act in behalf of another. 348.2 Section 348.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT REPRESENTATIVE PAYMENT § 348.2 Recognition by the Board of...

20 CFR 348.2 - Recognition by the Board of a person to act in behalf of another.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Recognition by the Board of a person to act in behalf of another. 348.2 Section 348.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT REPRESENTATIVE PAYMENT § 348.2 Recognition by the Board of...

20 CFR 348.2 - Recognition by the Board of a person to act in behalf of another.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Recognition by the Board of a person to act in behalf of another. 348.2 Section 348.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT REPRESENTATIVE PAYMENT § 348.2 Recognition by the Board of a...

20 CFR 348.2 - Recognition by the Board of a person to act in behalf of another.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Recognition by the Board of a person to act in behalf of another. 348.2 Section 348.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT REPRESENTATIVE PAYMENT § 348.2 Recognition by the Board of a...

Pulsed laser deposited MnCo{sub 2}O{sub 4} protective layer on SS430 for solid oxide fuel cell application

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

Gaur, Anshu, E-mail: gauranshu20@gmail.com, E-mail: ahamed.vza@gmail.com; Mohiddon, Md. Ahamad, E-mail: gauranshu20@gmail.com, E-mail: ahamed.vza@gmail.com; Prasad, Muvva D.

2016-05-23

The growth and oxidation study of pulsed laser deposited MnCo{sub 2}O{sub 4} protective layer on SS430 substrate for solid oxide fuel cell application is demonstrated. MnCo{sub 2}O{sub 4} has been achieved in three different ways including, deposition at higher substrate temperature (700°C), and deposition at room temperature on pre-oxidized and untreated SS430 substrate followed by annealing at 700°C for 2 hrs. X-ray diffraction and Raman spectroscopy has been applied to demonstrate the kind of phases developed in each case. These three samples were subjected to heat treatment at 750°C for 5 hr. The extent of undesired Fe{sub 2}O{sub 3} phasemore » formation in the post deposition heat treated samples is discussed based on Raman spectroscopic results.« less

Effects of Ce on Inclusions, Microstructure, Mechanical Properties, and Corrosion Behavior of AISI 202 Stainless Steel

NASA Astrophysics Data System (ADS)

Cai, Guojun; Li, Changsheng

2015-10-01

The sizes and morphologies of nonmetallic inclusions, microhardness, tensile strength, and Charpy impact toughness in AISI 202 stainless steel with different Ce contents were synthetically analyzed by means of SEM, TEM, microhardness tester, and tensile and Charpy impact tests. Effects of Ce addition on the corrosion behavior were investigated in 5 wt.% H2SO4 solution for different periods of time through measuring AC impedance. The EIS measurements indicate that the steels with Ce addition exhibit higher R p values than those without Ce, which illustrates the relative resistance to uniform corrosion is accompanied by an increasing Ce addition. Ce addition to AISI 202 stainless steel improves its uniform corrosion resistance owing to metamorphic inclusions and the improvement of electrode potential in matrix. Upon increasing Ce addition, the indentation morphology of samples transfers from sink-in types to pile-up types, explaining good machinability of steels containing Ce. It is witnessed from the fracture mode that Ce refines the grain size of steels, significantly increasing the strength; in the meantime, its plasticity is improved, thereby solving the contradiction between the strength and the plasticity of steels. It is concluded that AISI 202 stainless steel with 0.016 wt.% Ce addition in the mass fraction has the best mechanical properties and the uniform corrosion resistance.

Zr/ZrC modified layer formed on AISI 440B stainless steel by plasma Zr-alloying

NASA Astrophysics Data System (ADS)

Shen, H. H.; Liu, L.; Liu, X. Z.; Guo, Q.; Meng, T. X.; Wang, Z. X.; Yang, H. J.; Liu, X. P.

2016-12-01

The surface Zr/ZrC gradient alloying layer was prepared by double glow plasma surface alloying technique to increase the surface hardness and wear resistance of AISI 440B stainless steel. The microstructure of the Zr/ZrC alloying layer formed at different alloying temperatures and times as well as its formation mechanism were discussed by using scanning electron microscopy, glow discharge optical emission spectrum, X-ray diffraction and X-ray photoelectron spectroscopy. The adhesive strength, hardness and tribological property of the Zr/ZrC alloying layer were also evaluated in the paper. The alloying surface consists of the Zr-top layer and ZrC-subsurface layer which adheres strongly to the AISI 440B steel substrate. The thickness of the Zr/ZrC alloying layer increases gradually from 16 μm to 23 μm with alloying temperature elevated from 900 °C to 1000 °C. With alloying time from 0.5 h to 4 h, the alloyed depth increases from 3 μm to 30 μm, and the ZrC-rich alloyed thickness vs time is basically parabola at temperature of 1000 °C. Both the hardness and wear resistance of the Zr/ZrC alloying layer obviously increase compared with untreated AISI 440B steel.

Niobium boride layers deposition on the surface AISI D2 steel by a duplex treatment

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

Kon, O., E-mail: okon42@htotmail.com; Pazarlioglu, S.; Sen, S.

2015-03-30

In this paper, we investigated the possibility of deposition of niobium boride layers on the surface of AISI D2 steel by a duplex treatment. At the first step of duplex treatment, boronizing was performed on AISI D2 steel samples at 1000{sup o}C for 2h and then pre-boronized samples niobized at 850°C, 900°C and 950°C using thermo-reactive deposition method for 1–4 h. The presence of the niobium boride layers such as NbB, NbB{sub 2} and Nb{sub 3}B{sub 4} and also iron boride phases such as FeB, Fe{sub 2}B were examined by X-ray diffraction analysis. Scanning electron microscope (SEM) and micro-hardness measurementsmore » were realized. Experimental studies showed that the depth of the coating layers increased with increasing temperature and times and also ranged from 0.42 µm to 2.43 µm, depending on treatment time and temperature. The hardness of the niobium boride layer was 2620±180 HV{sub 0.005}.« less

Is PiSS Alpha-1 Antitrypsin Deficiency Associated with Disease?

PubMed

McGee, Dawn; Schwarz, Laura; McClure, Rebecca; Peterka, Lauren; Rouhani, Farshid; Brantly, Mark; Strange, Charlie

2010-01-01

Background. Alpha-1 antitrypsin deficiency (AAT) is an inherited condition that predisposes to lung and/or liver disease. Objective. The current study examined the clinical features of the PiSS genotype. Methods. Nineteen study participants (PiSS) and 29 matched control participants (PiMM) were telephone interviewed using a standardized questionnaire. Demographic features, cigarette smoking, vocation, medication history, and clinical diagnoses were compared. Statistical analysis was performed. Finally, a comprehensive literature review was performed by two investigators. Results. 12/19 (63.2%) study participants reported the presence of lung and/or liver disease compared to 12/29 (41.4%) control participants. There trended toward having a higher frequency of medication allergies in the study population (42.11% versus 20.69%). Conclusions. The PiSS genotype was associated with a similar incidence of obstructive lung disease to controls. Selective bias intrinsic in testing for AAT deficiency and the rarity of the PiSS genotype will make future study of this association dependent on population-based tests.

Is PiSS Alpha-1 Antitrypsin Deficiency Associated with Disease?

PubMed Central

McGee, Dawn; Schwarz, Laura; McClure, Rebecca; Peterka, Lauren; Rouhani, Farshid; Brantly, Mark; Strange, Charlie

2010-01-01

Background. Alpha-1 antitrypsin deficiency (AAT) is an inherited condition that predisposes to lung and/or liver disease. Objective. The current study examined the clinical features of the PiSS genotype. Methods. Nineteen study participants (PiSS) and 29 matched control participants (PiMM) were telephone interviewed using a standardized questionnaire. Demographic features, cigarette smoking, vocation, medication history, and clinical diagnoses were compared. Statistical analysis was performed. Finally, a comprehensive literature review was performed by two investigators. Results. 12/19 (63.2%) study participants reported the presence of lung and/or liver disease compared to 12/29 (41.4%) control participants. There trended toward having a higher frequency of medication allergies in the study population (42.11% versus 20.69%). Conclusions. The PiSS genotype was associated with a similar incidence of obstructive lung disease to controls. Selective bias intrinsic in testing for AAT deficiency and the rarity of the PiSS genotype will make future study of this association dependent on population-based tests. PMID:21687342

20 CFR 404.348 - When is a child living with me in my care?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false When is a child living with me in my care? 404.348 Section 404.348 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS... activities and you do not make important decisions about his or her needs, either alone or with help from...

Microstructure and Mechanical Properties of Laser Clad and Post-cladding Tempered AISI H13 Tool Steel

NASA Astrophysics Data System (ADS)

Telasang, Gururaj; Dutta Majumdar, Jyotsna; Wasekar, Nitin; Padmanabham, G.; Manna, Indranil

2015-05-01

This study reports a detailed investigation of the microstructure and mechanical properties (wear resistance and tensile strength) of hardened and tempered AISI H13 tool steel substrate following laser cladding with AISI H13 tool steel powder in as-clad and after post-cladding conventional bulk isothermal tempering [at 823 K (550 °C) for 2 hours] heat treatment. Laser cladding was carried out on AISI H13 tool steel substrate using a 6 kW continuous wave diode laser coupled with fiber delivering an energy density of 133 J/mm2 and equipped with a co-axial powder feeding nozzle capable of feeding powder at the rate of 13.3 × 10-3 g/mm2. Laser clad zone comprises martensite, retained austenite, and carbides, and measures an average hardness of 600 to 650 VHN. Subsequent isothermal tempering converted the microstructure into one with tempered martensite and uniform dispersion of carbides with a hardness of 550 to 650 VHN. Interestingly, laser cladding introduced residual compressive stress of 670 ± 15 MPa, which reduces to 580 ± 20 MPa following isothermal tempering. Micro-tensile testing with specimens machined from the clad zone across or transverse to cladding direction showed high strength but failure in brittle mode. On the other hand, similar testing with samples sectioned from the clad zone parallel or longitudinal to the direction of laser cladding prior to and after post-cladding tempering recorded lower strength but ductile failure with 4.7 and 8 pct elongation, respectively. Wear resistance of the laser surface clad and post-cladding tempered samples (evaluated by fretting wear testing) registered superior performance as compared to that of conventional hardened and tempered AISI H13 tool steel.

Alma Survey of Circumstellar Disks in the Young Stellar Cluster IC 348

NASA Astrophysics Data System (ADS)

Ruíz-Rodríguez, D.; Cieza, L. A.; Williams, J. P.; Andrews, S. M.; Principe, D. A.; Caceres, C.; Canovas, H.; Casassus, S.; Schreiber, M. R.; Kastner, J. H.

2018-05-01

We present a 1.3 mm continuum survey of the young (2-3 Myr) stellar cluster IC 348, which lies at a distance of 310 pc, and is dominated by low-mass stars (M⋆ ˜ 0.1-0.6 M⊙). We observed 136 Class II sources (disks that are optically thick in the infrared) at 0.8″ (200 au) resolution with a 3σ sensitivity of ˜ 0.45 mJy (Mdust ˜ 1.3 M⊕). We detect 40 of the targets and construct a mm-continuum luminosity function. We compare the disk mass distribution in IC 348 to those of younger and older regions, taking into account the dependence on stellar mass. We find a clear evolution in disk masses from 1 to 5-10 Myr. The disk masses in IC 348 are significantly lower than those in Taurus (1-3 Myr) and Lupus (1-3 Myr), similar to those of Chamaleon I, (2-3 Myr) and σ Ori (3-5 Myr) and significantly higher than in Upper Scorpius (5-10 Myr). About 20 disks in our sample (˜5% of the cluster members) have estimated masses (dust + gas) >1 MJup and hence might be the precursors of giant planets in the cluster. Some of the most massive disks include transition objects with inner opacity holes based on their infrared SEDs. From a stacking analysis of the 96 non-detections, we find that these disks have a typical dust mass of just ≲ 0.4 M⊕, even though the vast majority of their infrared SEDs remain optically thick and show little signs of evolution. Such low-mass disks may be the precursors of the small rocky planets found by Kepler around M-type stars.

Thermal Properties of G-348 Graphite

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

McEligot, Donald; Swank, W. David; Cottle, David L.

2016-05-01

Fundamental measurements have been obtained in the INL Graphite Characterization Laboratory to deduce the temperature dependence of thermal conductivity for G-348 isotropic graphite, which has been used by City College of New York in thermal experiments related to gas-cooled nuclear reactors. Measurements of thermal diffusivity, mass, volume and thermal expansion were converted to thermal conductivity in accordance with ASTM Standard Practice C781-08. Data are tabulated and a preliminary correlation for the thermal conductivity is presented as a function of temperature from laboratory temperature to 1000C.

Thermal Properties of G-348 Graphite

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

McEligot, Donald M.; Swank, W. David; Cottle, David L.

Fundamental measurements have been obtained in the INL Graphite Characterization Laboratory to deduce the temperature dependence of thermal conductivity for G-348 isotropic graphite, which has been used by City College of New York in thermal experiments related to gas-cooled nuclear reactors. Measurements of thermal diffusivity, mass, volume and thermal expansion were converted to thermal conductivity in accordance with ASTM Standard Practice C781-08 (R-2014). Data are tabulated and a preliminary correlation for the thermal conductivity is presented as a function of temperature from laboratory temperature to 1000C.

The effect of surface nanocrystallization on plasma nitriding behaviour of AISI 4140 steel

NASA Astrophysics Data System (ADS)

Li, Yang; Wang, Liang; Zhang, Dandan; Shen, Lie

2010-11-01

A plastic deformation surface layer with nanocrystalline grains was produced on AISI 4140 steel by means of surface mechanical attrition treatment (SMAT). Plasma nitriding of SMAT and un-SMAT AISI 4140 steel was carried out by a low-frequency pulse excited plasma unit. A series of nitriding experiments has been conducted at temperatures ranging from 380 to 500 °C for 8 h in an NH 3 gas. The samples were characterized using X-ray diffraction, scanning electron microscopy, optical microscopy and Vickers microhardness tester. The results showed that a much thicker compound layer with higher hardness was obtained for the SMAT samples when compared with un-SMAT samples after nitriding at the low temperature. In particular, plasma nitriding SMAT AISI 4140 steel at 380 °C for 8 h can produced a compound layer of 2.5 μm thickness with very high hardness on the surface, which is similar to un-SMAT samples were plasma nitrided at approximately 430 °C within the same time.

Colloquium on Large Scale Improvement: Implications for AISI

ERIC Educational Resources Information Center

McEwen, Nelly, Ed.

2008-01-01

The Alberta Initiative for School Improvement (AISI) is a province-wide partnership program whose goal is to improve student learning and performance by fostering initiatives that reflect the unique needs and circumstances of each school authority. It is currently ending its third cycle and ninth year of implementation. "The Colloquium on…

Mechanochemical regulations of RPA's binding to ssDNA

NASA Astrophysics Data System (ADS)

Chen, Jin; Le, Shimin; Basu, Anindita; Chazin, Walter J.; Yan, Jie

2015-03-01

Replication protein A (RPA) is a ubiquitous eukaryotic single-stranded DNA (ssDNA) binding protein that serves to protect ssDNA from degradation and annealing, and as a template for recruitment of many downstream factors in virtually all DNA transactions in cell. During many of these transactions, DNA is tethered and is likely subject to force. Previous studies of RPA's binding behavior on ssDNA were conducted in the absence of force; therefore the RPA-ssDNA conformations regulated by force remain unclear. Here, using a combination of atomic force microscopy imaging and mechanical manipulation of single ssDNA tethers, we show that force mediates a switch of the RPA bound ssDNA from amorphous aggregation to a much more regular extended conformation. Further, we found an interesting non-monotonic dependence of the binding affinity on monovalent salt concentration in the presence of force. In addition, we discovered that zinc in micromolar concentrations drives ssDNA to a unique, highly stiff and more compact state. These results provide new mechanochemical insights into the influences and the mechanisms of action of RPA on large single ssDNA.

Improving the corrosion wear resistance of AISI 316L stainless steel by particulate reinforced Ni matrix composite alloying layer

NASA Astrophysics Data System (ADS)

Xu, Jiang; Zhuo, Chengzhi; Tao, Jie; Jiang, Shuyun; Liu, Linlin

2009-01-01

In order to overcome the problem of corrosion wear of AISI 316L stainless steel (SS), two kinds of composite alloying layers were prepared by a duplex treatment, consisting of Ni/nano-SiC and Ni/nano-SiO2 predeposited by brush plating, respectively, and subsequent surface alloying with Ni-Cr-Mo-Cu by a double glow process. The microstructure of the two kinds of nanoparticle reinforced Ni-based composite alloying layers was investigated by means of SEM and TEM. The electrochemical corrosion behaviour of composite alloying layers compared with the Ni-based alloying layer and 316L SS under different conditions was characterized by potentiodynamic polarization test and electrochemical impedance spectroscopy. Results showed that under alloying temperature (1000 °C) conditions, amorphous nano-SiO2 particles still retained the amorphous structure, whereas nano-SiC particles were decomposed and Ni, Cr reacted with SiC to form Cr6.5Ni2.5Si and Cr23C6. In static acidic solution, the corrosion resistance of the composite alloying layer with the brush plating Ni/nano-SiO2 particles interlayer is lower than that of the Ni-based alloying layer. However, the corrosion resistance of the composite alloying layer with the brush plating Ni/nano-SiO2 particles interlayer is prominently superior to that of the Ni-based alloying layer under acidic flow medium condition and acidic slurry flow condition. The corrosion resistance of the composite alloying layer with the brush plating Ni/nano-SiC particles interlayer is evidently lower than that of the Ni-based alloying layer, but higher than that of 316L SS under all test conditions. The results show that the highly dispersive nano-SiO2 particles are helpful in improving the corrosion wear resistance of the Ni-based alloying layer, whereas carbides and silicide phase are deleterious to that of the Ni-based alloying layer due to the fact that the preferential removal of the matrix around the precipitated phase takes place by the chemical

Modeling and Investigation of the Wear Resistance of Salt Bath Nitrided Aisi 4140 via ANN

NASA Astrophysics Data System (ADS)

Ekinci, Şerafettin; Akdemir, Ahmet; Kahramanli, Humar

2013-05-01

Nitriding is usually used to improve the surface properties of steel materials. In this way, the wear resistance of steels is improved. We conducted a series of studies in order to investigate the microstructural, mechanical and tribological properties of salt bath nitrided AISI 4140 steel. The present study has two parts. For the first phase, the tribological behavior of the AISI 4140 steel which was nitrided in sulfinuz salt bath (SBN) was compared to the behavior of the same steel which was untreated. After surface characterization using metallography, microhardness and sliding wear tests were performed on a block-on-cylinder machine in which carbonized AISI 52100 steel discs were used as the counter face. For the examined AISI 4140 steel samples with and without surface treatment, the evolution of both the friction coefficient and of the wear behavior were determined under various loads, at different sliding velocities and a total sliding distance of 1000 m. The test results showed that wear resistance increased with the nitriding process, friction coefficient decreased due to the sulfur in salt bath and friction coefficient depended systematically on surface hardness. For the second part of this study, four artificial neural network (ANN) models were designed to predict the weight loss and friction coefficient of the nitrided and unnitrided AISI 4140 steel. Load, velocity and sliding distance were used as input. Back-propagation algorithm was chosen for training the ANN. Statistical measurements of R2, MAE and RMSE were employed to evaluate the success of the systems. The results showed that all the systems produced successful results.

49 CFR 178.348-2 - Material and thickness of material.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Bulkheads and Baffles When Used as Tank Reinforcement) Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL)—Expressed in Decimals of an Inch After Forming... Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL...

49 CFR 178.348-2 - Material and thickness of material.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Bulkheads and Baffles When Used as Tank Reinforcement) Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL)—Expressed in Decimals of an Inch After Forming... Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL...

49 CFR 178.348-2 - Material and thickness of material.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Bulkheads and Baffles When Used as Tank Reinforcement) Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL)—Expressed in Decimals of an Inch After Forming... Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL...

49 CFR 178.348-2 - Material and thickness of material.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Bulkheads and Baffles When Used as Tank Reinforcement) Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL)—Expressed in Decimals of an Inch After Forming... Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL...

49 CFR 178.348-2 - Material and thickness of material.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Bulkheads and Baffles When Used as Tank Reinforcement) Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL)—Expressed in Decimals of an Inch After Forming... Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL...

Microstructural evolution and precipitation behavior in heat affected zone of Inconel 625 and AISI 904L dissimilar welds

NASA Astrophysics Data System (ADS)

Senthur Prabu, S.; Devendranath Ramkumar, K.; Arivazhagan, N.

2017-11-01

In the present investigation an attempt has been made to join the dissimilar combination of Inconel 625 super alloy and super austenitic stainless steel (AISI 904L) using manual multi-pass continuous current gas tungsten arc (CCGTA) welding processes. Two different filler wires such as ERNiCrMo-4 and ERNiCrCoMo-1 have been used to compare the metallurgical properties of these welded joints. Both optical microscopy and scanning electron microscopy techniques were adopted to disseminate the microstructure traits of these weldments. Formation of secondary phases at the HAZ and weld interface of AISI 904L was witnessed while using the ERNiCrCoMo-1 filler, along with Solidification Grain Boundary (SGB) and Migrated Grain Boundary (MGB) were also observed at the weld zone.

Microstructural Evolutions During Reversion Annealing of Cold-Rolled AISI 316 Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Naghizadeh, Meysam; Mirzadeh, Hamed

2018-03-01

Microstructural evolutions during reversion annealing of a plastically deformed AISI 316 stainless steel were investigated and three distinct stages were identified: the reversion of strain-induced martensite to austenite, the primary recrystallization of the retained austenite, and the grain growth process. It was found that the slow kinetics of recrystallization at lower annealing temperatures inhibit the formation of an equiaxed microstructure and might effectively impair the usefulness of this thermomechanical treatment for the objective of grain refinement. By comparing the behavior of AISI 316 and 304 alloys, it was found that the mentioned slow kinetics is related to the retardation effect of solute Mo in the former alloy. At high reversion annealing temperature, however, an equiaxed austenitic microstructure was achieved quickly in AISI 316 stainless steel due to the temperature dependency of retardation effect of molybdenum, which allowed the process of recrystallization to happen easily. Conclusively, this work can shed some light on the issues of this efficient grain refining approach for microstructural control of austenitic stainless steels.

Stoichiometric titanium dioxide ion implantation in AISI 304 stainless steel for corrosion protection

NASA Astrophysics Data System (ADS)

Hartwig, A.; Decker, M.; Klein, O.; Karl, H.

2015-12-01

The aim of this study is to evaluate the applicability of highly chemically inert titanium dioxide synthesized by ion beam implantation for corrosion protection of AISI 304 stainless steel in sodium chloride solution. More specifically, the prevention of galvanic corrosion between carbon-fiber reinforced plastic (CFRP) and AISI 304 was investigated. Corrosion performance of TiO2 implanted AISI 304 - examined for different implantation and annealing parameters - is strongly influenced by implantation fluence. Experimental results show that a fluence of 5 × 1016 cm-2 (Ti+) and 1 × 1017 cm-2 (O+) is sufficient to prevent pitting corrosion significantly, while galvanic corrosion with CFRP can already be noticeably reduced by an implantation fluence of 5 × 1015 cm-2 (Ti+) and 1 × 1016 cm-2 (O+). Surface roughness, implantation energy and annealing at 200 °C and 400 °C show only little influence on the corrosion behavior. TEM analysis indicates the existence of stoichiometric TiO2 inside the steel matrix for medium fluences and the formation of a separated metal oxide layer for high fluences.

Microstructural Evolutions During Reversion Annealing of Cold-Rolled AISI 316 Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Naghizadeh, Meysam; Mirzadeh, Hamed

2018-06-01

Microstructural evolutions during reversion annealing of a plastically deformed AISI 316 stainless steel were investigated and three distinct stages were identified: the reversion of strain-induced martensite to austenite, the primary recrystallization of the retained austenite, and the grain growth process. It was found that the slow kinetics of recrystallization at lower annealing temperatures inhibit the formation of an equiaxed microstructure and might effectively impair the usefulness of this thermomechanical treatment for the objective of grain refinement. By comparing the behavior of AISI 316 and 304 alloys, it was found that the mentioned slow kinetics is related to the retardation effect of solute Mo in the former alloy. At high reversion annealing temperature, however, an equiaxed austenitic microstructure was achieved quickly in AISI 316 stainless steel due to the temperature dependency of retardation effect of molybdenum, which allowed the process of recrystallization to happen easily. Conclusively, this work can shed some light on the issues of this efficient grain refining approach for microstructural control of austenitic stainless steels.

Improving by postoxidation of corrosion resistance of plasma nitrocarburized AISI 316 stainless steels

NASA Astrophysics Data System (ADS)

Yenilmez, A.; Karakan, M.; Çelik, İ.

2017-01-01

Austenitic stainless steels are widely used in several industries such as chemistry, food, health and space due to their perfect corrosion resistance. However, in addition to corrosion resistance, the mechanic and tribological features such as wear resistance and friction are required to be good in the production and engineering of this type of machines, equipment and mechanic parts. In this study, ferritic (FNC) and austenitic (ANC) nitrocarburizing were applied on AISI 316 stainless steel specimens with perfect corrosion resistance in the plasma environment at the definite time (4 h) and constant gas mixture atmosphere. In order to recover corrosion resistance which was deteriorated after nitrocarburizing again, plasma postoxidation process (45 min) was applied. After the duplex treatment, the specimens' structural analyses with XRD and SEM methods, corrosion analysis with polarization method and surface hardness with microhardness method were examined. At the end of the studies, AISI 316 surface hardness of stainless steel increased with nitrocarburizing process, but the corrosion resistance was deteriorated with FNC (570 °C) and ANC (670 °C) nitrocarburizing. With the following of the postoxidation treatment, it was detected that the corrosion resistance became better and it approached its value before the process.

Improvement of adhesion and barrier properties of biomedical stainless steel by deposition of YSZ coatings using RF magnetron sputtering

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

Sánchez-Hernández, Z.E.; CICATA—Altamira, IPN. Grupo CIAMS, Km 14.5, Carretera Tampico-Puerto Industrial Altamira, C. P. 89600, Altamira, Tamps, México; Domínguez-Crespo, M.A., E-mail: mdominguezc@ipn.mx

The AISI 316L stainless steel (SS) has been widely used in both artificial knee and hip joints in biomedical applications. In the present study, yttria stabilized zirconia (YSZ, ZrO{sub 2} + 8% Y{sub 2}O{sub 3}) films were deposited on AISI 316L SS by radio-frequency magnetron sputtering using different power densities (50–250 W) and deposition times (30–120 min) from a YSZ target. The crystallographic orientation and surface morphology were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effects of the surface modification on the corrosion performance of AISI 316L SS were evaluated in phosphatemore » buffered saline (PBS) solution using an electrochemical test on both the virgin and coated samples. The YSZ coatings have a (111) preferred orientation during crystal growth along the c-axis for short deposition times (30–60 min), whereas a polycrystalline structure forms during deposition times from 90 to 120 min. The corrosion protective character of the YSZ coatings depends on the crystal size and film thickness. A significant increase in adhesion and corrosion resistance by at least a factor of 46 and a higher breakdown potential were obtained for the deposited coatings at 200 W (120 min). - Highlights: • Well-formed and protective YSZ coatings were achieved on AISI 316L SS substrates. • Films grown at high power and long deposition time have polycrystalline structures. • The crystal size varies from ∼ 5 to 30 nm as both power and deposition time increased. • The differences of corrosion resistance are attributed to internal film structure.« less

Microstructure and Corrosion Behavior of Laser Melted 304L SS Weldment in Nitric Acid Medium

NASA Astrophysics Data System (ADS)

Suresh, Girija; Kishor, P. S. V. R. A.; Dasgupta, Arup; Upadhyay, B. N.; Mallika, C.; Kamachi Mudali, U.

2017-02-01

The manuscript presents the effect of laser surface melting on the corrosion property of 304L SS weldment in nitric acid medium. 304L SS weldment was prepared by gas tungsten arc welding process and subsequently laser surface melted using Nd:YAG laser. The microstructure and corrosion resistance of laser surface melted 304L SS weldment was evaluated and compared with that of 304L SS as-weldment and 304L SS base. Microstructural evaluation was carried out using optical and scanning electron microscopes attached with energy-dispersive x-ray spectroscopy. Corrosion investigations were carried out in 4 and 8 M nitric acid by potentiodynamic polarization technique. From the results, it was found that laser surface melting of the weldment led to chemical and microstructural homogeneities, accompanied by a substantial decrease in delta ferrite content, that enhanced the corrosion resistance of the weldment in 4 and 8 M nitric acid. However, the enhancement in the corrosion resistance was not substantial. The presence of small amount of delta ferrite (2-4 wt.%) in the laser surface melted specimens was found to be detrimental in nitric acid. X-ray photoelectron spectroscopy studies were carried out to investigate the composition of the passive film.

PREFACE: The 4th Symposium on the Mechanics of Slender Structures (MoSS2013)

NASA Astrophysics Data System (ADS)

Cao, Dengqing; Kaczmarczyk, Stefan

2013-07-01

This volume of Journal of Physics: Conference Series contains papers presented at the 4th Symposium on the Mechanics of Slender Structures (MoSS2013) run under the auspices of the Institute of Physics Applied Mechanics Group and hosted by Harbin Institute of Technology (China) from 7-9 January 2013. The conference has been organized in collaboration with the Technical Committee on Vibration and Sound of the American Society of Mechanical Engineers and follows a one day seminar on Ropes, Cables, Belts and Chains: Theory and Applications and the MoSS2006 symposium held at the University of Northampton (UK) in 2004 and 2006, respectively, the MoSS2008 symposium held at the University of Maryland Baltimore County (USA) in 2008 and the MoSS2010 symposium hosted by Mondragon University and held in San Sebastian (Spain) in 2010. The remit of the Symposium on the Mechanics of Slender Structures series involves a broad range of scientific areas. Applications of slender structures include terrestrial, marine and space systems. Moving elastic elements such as ropes, cables, belts and tethers are pivotal components of many engineering systems. Their lengths often vary when the system is in operation. The applications include vertical transportation installations and, more recently, space tether propulsion systems. Traction drive elevator installations employ ropes and belts of variable length as a means of suspension, and also for the compensation of tensile forces over the traction sheave. In cranes and mine hoists, cables and ropes are subject to length variation in order to carry payloads. Tethers experiencing extension and retraction are important components of offshore and marine installations, as well as being proposed for a variety of different space vehicle propulsion systems based on different applications of momentum exchange and electrodynamic interactions with planetary magnetic fields. Furthermore, cables and slender rods are used extensively in civil engineering

VMD-SS: A graphical user interface plug-in to calculate the protein secondary structure in VMD program.

PubMed

Yahyavi, Masoumeh; Falsafi-Zadeh, Sajad; Karimi, Zahra; Kalatarian, Giti; Galehdari, Hamid

2014-01-01

The investigation on the types of secondary structure (SS) of a protein is important. The evolution of secondary structures during molecular dynamics simulations is a useful parameter to analyze protein structures. Therefore, it is of interest to describe VMD-SS (a software program) for the identification of secondary structure elements and its trajectories during simulation for known structures available at the Protein Data Bank (PDB). The program helps to calculate (1) percentage SS, (2) SS occurrence in each residue, (3) percentage SS during simulation, and (4) percentage residues in all SS types during simulation. The VMD-SS plug-in was designed using TCL script and stride to calculate secondary structure features. The database is available for free at http://science.scu.ac.ir/HomePage.aspx?TabID=13755.

AG-348 enhances pyruvate kinase activity in red blood cells from patients with pyruvate kinase deficiency

PubMed Central

Hixon, Jeff; Kosinski, Penelope A.; Cianchetta, Giovanni; Histen, Gavin; Chen, Yue; Hill, Collin; Gross, Stefan; Si, Yaguang; Johnson, Kendall; DeLaBarre, Byron; Luo, Zhiyong; Gu, Zhiwei; Yao, Gui; Tang, Huachun; Fang, Cheng; Xu, Yingxia; Lv, Xiaobing; Biller, Scott; Su, Shin-San Michael; Yang, Hua; Popovici-Muller, Janeta; Salituro, Francesco; Silverman, Lee; Dang, Lenny

2017-01-01

Pyruvate kinase (PK) deficiency is a rare genetic disease that causes chronic hemolytic anemia. There are currently no targeted therapies for PK deficiency. Here, we describe the identification and characterization of AG-348, an allosteric activator of PK that is currently in clinical trials for the treatment of PK deficiency. We demonstrate that AG-348 can increase the activity of wild-type and mutant PK enzymes in biochemical assays and in patient red blood cells treated ex vivo. These data illustrate the potential for AG-348 to restore the glycolytic pathway activity in patients with PK deficiency and ultimately lead to clinical benefit. PMID:28760888

22 CFR 34.8 - Notice and demand for payment.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Actions § 34.8 Notice and demand for payment. (a) STATE shall promptly hand deliver or send by first-class mail to the debtor at the debtor's most current address in the records of STATE at least one written notice. Written demand under this subpart may be preceded by other appropriate actions under this part...

49 CFR 178.348-5 - Pressure and leakage test.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test. Test..., and the inspection pressure is tank MAWP. [Amdt. 178-89, 54 FR 25032, June 12, 1989. Redesignated by...

49 CFR 178.348-5 - Pressure and leakage test.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test. Test..., and the inspection pressure is tank MAWP. [Amdt. 178-89, 54 FR 25032, June 12, 1989. Redesignated by...

49 CFR 178.348-5 - Pressure and leakage test.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test. Test..., and the inspection pressure is tank MAWP. [Amdt. 178-89, 54 FR 25032, June 12, 1989. Redesignated by...

49 CFR 178.348-5 - Pressure and leakage test.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test. Test..., and the inspection pressure is tank MAWP. [Amdt. 178-89, 54 FR 25032, June 12, 1989. Redesignated by...

49 CFR 178.348-5 - Pressure and leakage test.

Code of Federal Regulations, 2010 CFR

2010-10-01

... PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure....5 times tank MAWP, and the inspection pressure is tank MAWP. [Amdt. 178-89, 54 FR 25032, June 12...

The Power of SS 433's Jets

NASA Technical Reports Server (NTRS)

Band, David F.

1999-01-01

We observed SS 433 for the third time with RXTE, this time simultaneously with a Nobeyama millimeter band monitoring campaign. These observations extended the RXTE coverage of SS 433's precession phases. and once again monitored the source during a binary eclipse. Our AO-2 campaign of a joint RXTE-VLBA-VLA-MERLIN observation was delayed to little more than a month before the AO-3 observations. We also had an AO-1 observation of SS 433. In each case we observed an eclipse of the compact ob'ect by the companion star, and had contemporaneous optical observations. We are analyzing all three sets of observations together. A publication is in preparation; Its completion will be supported by the remaining AO-2 funds. Here I will summarize the general results and point out the relevant features of the AO-3 observations. The spectrum is detected to approx. 50 keV, which is entirely within the PCA energy band. We find that the HEXTE data do not add significantly to the spectrum, and most of our fits are without HEXTE. We find that the continuum can be fit with a power law with an exponential cutoff; the photon index is usually approx. 1.4. A line at approx. 6.4 keV is definitely required, and the fits improve significant, if we add a second line, also with an energy in the iron K(alpha) complex, and an absorption edge. The edge usually has an energy of approx. 5.8 keV, which does not correspond to any known physical feature. and may be an instrumental artifact. This is under further investigation.

Surface fatigue life of CBN and vitreous ground carburized and hardened AISI 9310 spur gears

NASA Technical Reports Server (NTRS)

Townsend, Dennis P.; Patel, P. R.

1988-01-01

Spur gear surface endurance tests were conducted to investigate CBN ground AISI 9310 spur gears for use in aircraft applications, to determine their endurance characteristics and to compare the results with the endurance of standard vitreous ground AISI 9310 spur gears. Tests were conducted with VIM-VAR AISI 9310 carburized and hardened gears that were finish ground with either CBN or vitreous grinding methods. Test conditions were an inlet oil temeprature of 320 K (116 F), an outlet oil temperature of 350 K (170 F), a maximum Hertz stress of 1.71 GPa (248 ksi), and a speed of 10,000 rpm. The CBN ground gears exhibited a surface fatigue life that was slightly better than the vitreous ground gears. The subsurface residual stress of the CBN ground gears was approximately the same as that for the standard vitreous ground gears for the CBN grinding method used.

Serotoninergic neuronal systems and ethanol sensitivity in long-sleep (LS) and short-sleep (SS) mice

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

French, T.A.; Weiner, N.

LS and SS mice selectively bred for differences in CNS sensitivity to ethanol (EtOH) exhibit markedly different sleep times (LS = 120 min; SS = 13 min) and differ considerably in hypothermic response following EtOH< 4 g/kg i.p. Basal levels of serotonin (5HT), 5-hydroxyindole acetic acid and 5HT turnover (defined as 5-hydroxy-tryptophan accumulation after inhibition of aromatic L-amino acid decarboxylase) in 6 brain regions (hypthalamus (HYP), dorsal raphe (DR), pontine-medullary raphe (PMR), striatum (STR), hippocampus (HIP) and cortex (CTX)) differ minimally between the two lines. 5 HT turnover in STR, HIP, CTX and PMR of either LS or SS micemore » or in HYP or DR of SS mice was not altered at either 20 or 120 min after EtOH, 4 g/kg. However, in LS mice, 5HT turnover was decreased 23% in HYP at 20 min and 30-34% in HYP and DR at 120 min. LS mice become 1.2 and 2.2/sup 0/ more hypothermic than SS mice at 20 and 120 min after EtOH, 4 g/kg. When approximately equi-effective hypothermic doses of EtOH were administered to LS (3.5 g/kg) and SS (5.0 g/kg) mice, differences in 5HT turnover were still apparent. Pentobarbital administration (65 mg/kg) both decreased brain 5HT turnover 30-60% and produced comparable degrees of hypothermia in LS and SS mice. These data suggest that the apparent increase in sensitivity to inhibition by EtOH of 5HT neurons of HYP and DR of LS mice may contribute to the greater degree of hypothermia induced in this line.« less

SS/RCS surface tension propellant acquisition/expulsion tankage technology program

NASA Technical Reports Server (NTRS)

1974-01-01

An evaluation of published propellant physical property data together with bubble point tests of fine-mesh screen in propellants, was conducted. The effort consisted of: (1) the collection and evaluation of pertinent physical property data for hydrazine (N2H4), monomethylhydrazine (MMH), and nitrogen tetroxide (N2O4); (2) testing to determine the effect of dissolved pressurant gas, temperature, purity, and system cleanliness or contamination on system bubble point, and (3) the compilation and publishing of both the literature and test results. The space shuttle reaction control system (SS/RCS) is a bipropellant system using N2O4 and MMH, while the auxiliary power system (SS/APU) employs monopropellant N2H4. Since both the RCS and the APU use a surface tension device for propellant acquisition, the propellant properties of interest are those which impact the design and operation of surface tension systems. Information on propellant density, viscosity, surface tension, and contact angle was collected, compiled, and evaluated.

27 CFR 19.348 - Determining age of mingled spirits.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Determining age of mingled... Spirits § 19.348 Determining age of mingled spirits. When spirits are mingled, the age of the spirits for the entire lot shall be the age of the youngest spirits contained in the lot. (Sec. 201, Pub. L. 85...

LoCuSS: Testing hydrostatic equilibrium in galaxy clusters

NASA Astrophysics Data System (ADS)

Smith, G. P.; Mazzotta, P.; Okabe, N.; Ziparo, F.; Mulroy, S. L.; Babul, A.; Finoguenov, A.; McCarthy, I. G.; Lieu, M.; Bahé, Y. M.; Bourdin, H.; Evrard, A. E.; Futamase, T.; Haines, C. P.; Jauzac, M.; Marrone, D. P.; Martino, R.; May, P. E.; Taylor, J. E.; Umetsu, K.

2016-02-01

We test the assumption of hydrostatic equilibrium in an X-ray luminosity selected sample of 50 galaxy clusters at 0.15 < z < 0.3 from the Local Cluster Substructure Survey (LoCuSS). Our weak-lensing measurements of M500 control systematic biases to sub-4 per cent, and our hydrostatic measurements of the same achieve excellent agreement between XMM-Newton and Chandra. The mean ratio of X-ray to lensing mass for these 50 clusters is β_X= 0.95± 0.05, and for the 44 clusters also detected by Planck, the mean ratio of Planck mass estimate to LoCuSS lensing mass is β_P= 0.95± 0.04. Based on a careful like-for-like analysis, we find that LoCuSS, the Canadian Cluster Comparison Project, and Weighing the Giants agree on β_P ≃ 0.9-0.95 at 0.15 < z < 0.3. This small level of hydrostatic bias disagrees at ˜5σ with the level required to reconcile Planck cosmology results from the cosmic microwave background and galaxy cluster counts.

Molecular determinants of the interactions between proteins and ssDNA.

PubMed

Mishra, Garima; Levy, Yaakov

2015-04-21

ssDNA binding proteins (SSBs) protect ssDNA from chemical and enzymatic assault that can derail DNA processing machinery. Complexes between SSBs and ssDNA are often highly stable, but predicting their structures is challenging, mostly because of the inherent flexibility of ssDNA and the geometric and energetic complexity of the interfaces that it forms. Here, we report a newly developed coarse-grained model to predict the structure of SSB-ssDNA complexes. The model is successfully applied to predict the binding modes of six SSBs with ssDNA strands of lengths of 6-65 nt. In addition to charge-charge interactions (which are often central to governing protein interactions with nucleic acids by means of electrostatic complementarity), an essential energetic term to predict SSB-ssDNA complexes is the interactions between aromatic residues and DNA bases. For some systems, flexibility is required from not only the ssDNA but also, the SSB to allow it to undergo conformational changes and the penetration of the ssDNA into its binding pocket. The association mechanisms can be quite varied, and in several cases, they involve the ssDNA sliding along the protein surface. The binding mechanism suggests that coarse-grained models are appropriate to study the motion of SSBs along ssDNA, which is expected to be central to the function carried out by the SSBs.

Estimating the Contact Endurance of the AISI 321 Stainless Steel Under Contact Gigacycle Fatigue Tests

NASA Astrophysics Data System (ADS)

Savrai, R. A.; Makarov, A. V.; Osintseva, A. L.; Malygina, I. Yu.

2018-02-01

Mechanical testing of the AISI 321 corrosion resistant austenitic steel for contact gigacycle fatigue has been conducted with the application of a new method of contact fatigue testing with ultrasonic frequency of loading according to a pulsing impact "plane-to-plane" contact scheme. It has been found that the contact endurance (the ability to resist the fatigue spalling) of the AISI 321 steel under contact gigacycle fatigue loading is determined by its plasticity margin and the possibility of additional hardening under contact loading. It is demonstrated that the appearance of localized deep and long areas of spalling on a material surface can serve as a qualitative characteristic for the loss of the fatigue strength of the AISI 321 steel under impact contact fatigue loading. The value of surface microhardness measured within contact spots and the maximum depth of contact damages in the peripheral zone of contact spots can serve as quantitative criteria for that purpose.

The Influence of The Temperature on Dry Friction of AISI 3315 Steel Sliding Against AISI 3150 Steel

NASA Astrophysics Data System (ADS)

Odabas, D.

2018-01-01

In this paper, the effects the influence of frictional heating on the wear of AISI 3315 Steel were investigated experimentally using a pin-on-ring geometry. All the tests were carried out in air without any lubricant. In order to understand the variation in frictional coefficient and temperature with load and speed, the friction tests were carried out at a speed of 1 m/s and loads in the range 115-250 N, and at a speed range 1-4 m/s, a load of 115 N. The sliding distance was 1500 m. The bulk temperature of the specimen was measured from the interface surface at a distance of 1 mm from the contact surface by using type K thermocouples (Ni-Cr-Ni). The coefficient of friction was determined as a function of test load and speed. The steady state coefficient of friction of the test material decreases with increasing load and speed due to the oxide formation. But the unsteady state coefficient of friction increases with an increase in load and speed.

49 CFR 178.348 - Specification DOT 412; cargo tank motor vehicle.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Specification DOT 412; cargo tank motor vehicle...) SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.348 Specification DOT 412; cargo tank motor vehicle. ...

49 CFR 178.348 - Specification DOT 412; cargo tank motor vehicle.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Specification DOT 412; cargo tank motor vehicle... SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.348 Specification DOT 412; cargo tank motor vehicle. ...

The Symbiotic System SS73 17 seen with Suzaku

NASA Technical Reports Server (NTRS)

Smith, Randall K.; Mushotzky, Richard; Kallman, Tim; Tueller, Jack; Mukai, Koji; Markwardt, Craig

2007-01-01

We observed with Suzaku the symbiotic star SS73 17, motivated by the discovery by the INTEGRAL satellite and the Swift BAT survey that it emits hard X-rays. Our observations showed a highly-absorbed X-ray spectrum with NH > loz3 emp2, equivalent to Av > 26, although the source has B magnitude 11.3 and is also bright in UV. The source also shows strong, narrow iron lines including fluorescent Fe K as well as Fe xxv and Fe XXVI. The X-ray spectrum can be fit with a thermal model including an absorption component that partially covers the source. Most of the equivalent width of the iron fluorescent line in this model can be explained as a combination of reprocessing in a dense absorber plus reflection off a white dwarf surface, but it is likely that the continuum is partially seen in reflection as well. Unlike other symbiotic systems that show hard X-ray emission (CH Cyg, RT Cru, T CrB, GX1+4), SS73 17 is not known to have shown nova-like optical variability, X-ray flashes, or pulsations, and has always shown faint soft X-ray emission. As a result, although it is likely a white dwarf, the nature of the compact object in SS73 17 is still uncertain. SS73 17 is probably an extreme example of the recently discovered and relatively small class of hard X-ray emitting symbiotic systems.

348. Caltrans, Photographer December 27, 1935 "TOWER E3"; VIEW OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

348. Caltrans, Photographer December 27, 1935 "TOWER E-3"; VIEW OF TOWER E-3 AND CANTILEVER TRUSS EAST ANCHOR ARM UNDER CONSTRUCTION. 7-1128 - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

Characterizing AISI 1045 steel surface duplex-treated by alternating current field enhanced pack aluminizing and nitriding

NASA Astrophysics Data System (ADS)

Xie, Fei; Zhang, Ge; Pan, Jianwei

2018-02-01

Thin cases and long treating time are shortcomings of conventional duplex treatment of aluminizing followed by nitriding (DTAN). Alternating current field (ACF) enhanced DTAN was carried out on AISI 1045 steel by applying an ACF to treated samples and treating agents with a pair of electrodes for overcoming those shortcomings. By investigating cases' structures, phases, composition and hardness distributions of differently treated samples, preliminary studies were made on characterizations of the ACF enhanced duplex treatment to AISI 1045 steel. The results show that, with the help of the ACF, the surface Al-rich phase Al5Fe2 formed in conventional pack aluminizing can be easily avoided and the aluminizing process is dramatically promoted. The aluminizing case can be nitrided either with conventional pack nitriding or ACF enhanced pack nitriding. By applying ACF to pack nitriding, the diffusion of nitrogen into the aluminizing case is promoted. AlN, Fe2∼3N and solid solution of N in iron are efficiently formed as a result of reactions of N with the aluminizing case. A duplex treated case with an effective thickness of more than 170 μm can be obtained by the alternating current field enhanced 4 h pack aluminizing plus 4 h pack nitriding.

Biomaterial Studies on AISI 316L Stainless Steel after Magnetoelectropolishing

PubMed Central

Hryniewicz, Tadeusz; Rokosz, Krzysztof; Filippi, Massimiliano

2009-01-01

The polarisation characteristics of the electropolishing process in a magnetic field (MEP – magnetoelectropolishing), in comparison with those obtained under standard/conventional process (EP) conditions, have been obtained. The occurrence of an EP plateau has been observed in view of the optimization of MEP process. Up-to-date stainless steel surface studies always indicated some amount of free-metal atoms apart from the detected oxides and hydroxides. Such a morphology of the surface film usually affects the thermodynamic stability and corrosion resistance of surface oxide layer and is one of the most important features of stainless steels. With this new MEP process we can improve metal surface properties by making the stainless steel more resistant to halides encountered in a variety of environments. Furthermore, in this paper the stainless steel surface film study results have been presented. The results of the corrosion research carried out by the authors on the behaviour of the most commonly used material − medical grade AISI 316L stainless steel both in Ringer’s body fluid and in aqueous 3% NaCl solution have been investigated and presented earlier elsewhere, though some of these results, concerning the EIS Nyquist plots and polarization curves are also revealed herein. In this paper an attempt to explain this peculiar performance of 316L stainless steel has been undertaken. The SEM studies, Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were performed on 316L samples after three treatments: MP – abrasive polishing (800 grit size), EP – conventional electrolytic polishing, and MEP – magnetoelectropolishing. It has been found that the proposed magnetoelectropolishing (MEP) process considerably modifies the morphology and the composition of the surface film, thus leading to improved corrosion resistance of the studied 316L SS.

21 CFR 348.50 - Labeling of external analgesic drug products.

Code of Federal Regulations, 2011 CFR

2011-04-01

... ingredient identified in § 348.10(a). (i) “Helps in the prevention of premature ejaculation.” (ii) “For temporary male genital desensitization, helping to slow the onset of ejaculation.” (iii) “Helps in...). (i) “Premature ejaculation may be due to a condition requiring medical supervision. If this product...

21 CFR 348.50 - Labeling of external analgesic drug products.

Code of Federal Regulations, 2010 CFR

2010-04-01

... ingredient identified in § 348.10(a). (i) “Helps in the prevention of premature ejaculation.” (ii) “For temporary male genital desensitization, helping to slow the onset of ejaculation.” (iii) “Helps in...). (i) “Premature ejaculation may be due to a condition requiring medical supervision. If this product...

Endurance and failure characteristics of modified Vasco X-2, CBS 600 and AISI 9310 spur gears. [aircraft construction materials

NASA Technical Reports Server (NTRS)

Townsend, D. P.; Zaretsky, E. V.

1980-01-01

Gear endurance tests and rolling-element fatigue tests were conducted to compare the performance of spur gears made from AISI 9310, CBS 600 and modified Vasco X-2 and to compare the pitting fatigue lives of these three materials. Gears manufactured from CBS 600 exhibited lives longer than those manufactured from AISI 9310. However, rolling-element fatigue tests resulted in statistically equivalent lives. Modified Vasco X-2 exhibited statistically equivalent lives to AISI 9310. CBS 600 and modified Vasco X-2 gears exhibited the potential of tooth fracture occurring at a tooth surface fatigue pit. Case carburization of all gear surfaces for the modified Vasco X-2 gears results in fracture at the tips of the gears.

Impact of structure and morphology of nanostructured ceria coating on AISI 304 oxidation kinetics

NASA Astrophysics Data System (ADS)

Aadhavan, R.; Suresh Babu, K.

2017-07-01

Nanostructured ceria-based coatings are shown to be protective against high-temperature oxidation of AISI 304 due to the dynamics of oxidation state and associated defects. However, the processing parameters of deposition have a strong influence in determining the structural and morphological aspects of ceria. The present work focuses on the effect of variation in substrate temperature (50-300 °C) and deposition rate (0.1-50 Å/s) of ceria in electron beam physical vapour evaporation method and correlates the changes in structure and morphology to high-temperature oxidation protection. Unlike deposition rate, substrate temperature exhibited a profound influence on crystallite size (7-18 nm) and oxygen vacancy concentration. Upon isothermal oxidation at 1243 K for 24 h, bare AISI 304 exhibited a linear mass gain with a rate constant of 3.0 ± 0.03 × 10-3 kg2 m-4 s-1 while ceria coating lowered the kinetics by 3-4 orders. Though the thickness of the coating was kept constant at 2 μm, higher deposition rate offered one order lower protection due to the porous nature of the coating. Variation in the substrate temperature modulated the porosity as well as oxygen vacancy concentration and displayed the best protection for coatings deposited at moderate substrate temperature. The present work demonstrates the significance of selecting appropriate processing parameters to obtain the required morphology for efficient high-temperature oxidation protection.

Antibacterial effects, biocompatibility and electrochemical behavior of zinc incorporated niobium oxide coating on 316L SS for biomedical applications

NASA Astrophysics Data System (ADS)

Pradeep PremKumar, K.; Duraipandy, N.; Manikantan Syamala, Kiran; Rajendran, N.

2018-01-01

In the present study, Nb2O5 (NZ0) composite coatings with various concentrations of zinc (NZ2, NZ4 & NZ6) are produced on 316L SS by sol-gel method with the aim of improving its antibacterial activity, bone formability and corrosion resistance properties. This work studied the surface characterization of NZ0, NZ2, NZ4 & NZ6 coated 316L SS by ATR-FTIR, XRD, HR-SEM with EDAX. The synthesized coatings were different in the morphological aspects, NZ0 shows mesoporous morphology whereas irregular cluster like morphology was observed for the zinc incorporated coatings. The chemical composition of the NZ0 and NZ4 composite coatings were studied by XPS and the results revealed that the zinc exist as ZnO and Nb as Nb2O5 in the coatings. The increase in the concentration of zinc in Nb2O5 increases the hydrophilic nature identified by water contact angle studies. The potentiodynamic polarization studies in simulated body fluid reveals the increase in polarization resistance with decrease in current density (icorr) and electrochemical impedance spectroscopic studies with increase in charge transfer resistance (Rct) and double layer capacitance (Qdl) were observed for NZ4 coated 316L SS. The inhibition of Staphylococcus aureus and Escherichia coli bacteria were identified for NZ4 coated 316L SS by bacterial viability studies. The NZ4 coated 316L SS showed better Osseo-integration by spreading the MG 63 osteoblast cells. The study results imply that zinc incorporated Nb2O5 (NZ4) composite coating exhibits antibacterial activity and also enhance the corrosion resistance and biocompatibility of the 316L SS.

Single-molecule FRET studies of the cooperative and non-cooperative binding kinetics of the bacteriophage T4 single-stranded DNA binding protein (gp32) to ssDNA lattices at replication fork junctions

PubMed Central

Lee, Wonbae; Gillies, John P.; Jose, Davis; Israels, Brett A.; von Hippel, Peter H.; Marcus, Andrew H.

2016-01-01

Gene 32 protein (gp32) is the single-stranded (ss) DNA binding protein of the bacteriophage T4. It binds transiently and cooperatively to ssDNA sequences exposed during the DNA replication process and regulates the interactions of the other sub-assemblies of the replication complex during the replication cycle. We here use single-molecule FRET techniques to build on previous thermodynamic studies of gp32 binding to initiate studies of the dynamics of the isolated and cooperative binding of gp32 molecules within the replication complex. DNA primer/template (p/t) constructs are used as models to determine the effects of ssDNA lattice length, gp32 concentration, salt concentration, binding cooperativity and binding polarity at p/t junctions. Hidden Markov models (HMMs) and transition density plots (TDPs) are used to characterize the dynamics of the multi-step assembly pathway of gp32 at p/t junctions of differing polarity, and show that isolated gp32 molecules bind to their ssDNA targets weakly and dissociate quickly, while cooperatively bound dimeric or trimeric clusters of gp32 bind much more tightly, can ‘slide’ on ssDNA sequences, and exhibit binding dynamics that depend on p/t junction polarities. The potential relationships of these binding dynamics to interactions with other components of the T4 DNA replication complex are discussed. PMID:27694621

High-latitude ionospheric inhomogeneities according to measurements on Kosmos 348

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

Dzhordzhio, N.V.

1975-01-01

The Kosmos 348 measurements showed that considerable ionospheric inhomogeneities are virtually always observed in the precipitation region of the high-latitude nighttime ionosphere in the presence of fluxes of injected electrons with E = 0.03 to 5 keV that exceed the critical value for current instability, unlike the situation in the presence of small fluxes.

Effect of filler metals on the mechanical properties of Inconel 625 and AISI 904L dissimilar weldments using gas tungsten arc welding

NASA Astrophysics Data System (ADS)

Senthur Prabu, S.; Devendranath Ramkumar, K.; Arivazhagan, N.

2017-11-01

In the present research work, dissimilar welding between Inconel 625 super alloy and AISI 904L super austenitic stainless steel using manual multi-pass continuous current gas tungsten arc (CCGTA) welding process employed with ERNiCrMo-4 and ERNiCrCoMo-1 fillers were performed to determine the mechanical properties and weldability. Tensile test results corroborated that the fracture had occurred at the parent metal of AISI 904L irrespective of filler used for all the trials. The presence of the macro and micro void coalescence in the fibrous matrix characterised for ductile mode of fracture. The hardness values at the weld interface of Inconel 625 side were observed to be higher for ERNiCrMo-4 filler due to the presence of strengthening elements such as W, Mo, Ni and Cr. The impact test accentuated that the weldments using ERNiCrMo-4 filler offered better impact toughness (41J) at room temperature. Bend test results showed that the weldments using these fillers exhibited good ductility without cracks.

Characteristics of interstitial lung disease in SS-A positive/Jo-1 positive inflammatory myopathy patients.

PubMed

Váncsa, Andrea; Csípo, I; Németh, J; Dévényi, K; Gergely, L; Dankó, K

2009-07-01

The strongest predictive factor for the development of interstitial lung disease (ILD) in myositis (IIM) patients is the presence of different antisynthetase antibodies. The aim of this study was to compare the clinical characteristics, radiological findings and therapeutic response between the anti-SS-A positive and negative antisynthetase syndrome (ASS) patients. A prospective study of 315 IIM patients was conducted including 27 anti-Jo-1 positive ASS patients. Mean disease duration was 46.6 (range 4-198) months. All patients fulfilled the classification criteria for IIM. All patients underwent chest radiography, pulmonary function tests and HRCT at he time of diagnosis and 6 months after the immunosuppressive therapy. Routine laboratory tests, RF, ANA, anti-ENA, anti-SS-A, anti-histidyl-transfer RNA antibody (Jo-1) measurements were performed in all patients. ILD was found to be present in 70.4% of ASS patients. The anti-SS-A negative ASS group had a more frequent association with alveolitis and responded well to immunosuppressive therapy (p < 0.05). HRCT scan showed more fibrosis in the SS-A positive group. 15.8% of patients died due to pulmonary or cardiac complications. In conclusion, coexistence of anti-SS-A and anti-Jo-1 antibody may be a good predictor for a more coarse and severe ILD in IIM patients who require a more aggressive approach in therapy.

Flow stress equations for type 304 stainless and AISI 1055 steels

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

Dadras, P.

A model for stress-strain behavior under hot working conditions has been proposed. Based on experimental data, equations for the dependence of flow stress on strain, strain rate, and temperature have been developed. Application to type 304 stainless steel and AISI 1055 steel has been demonstrated.

Construction, characterization and evaluation of the protective efficacy of the Streptococcus suis double mutant strain ΔSsPep/ΔSsPspC as a live vaccine candidate in mice.

PubMed

Hu, Jin; You, Wujin; Wang, Bin; Hu, Xueying; Tan, Chen; Liu, Jinlin; Chen, Huanchun; Bei, Weicheng

2015-01-01

Streptococcus suis serotype 2 (S. suis 2) causes sepsis and meningitis in piglets and humans, and results in one of the most serious bacterial diseases affecting the production of commercial pigs around the world. Due to the failure of the current inactivated vaccine to protect against the disease, development of a new attenuated live vaccine against S. suis 2 by deleting essential virulence factors is urgently needed. We have previously reported the construction and characterization of an SsPep single gene deletion mutant strain ΔSsPep based on S. suis 2. Our previous results have shown that SsPep plays a critical role in the pathogenesis of S. suis 2. In this study, a precisely defined double-deletion mutant ΔSsPep/ΔSsPspC of S. suis 2 without antibiotic-resistance markers was constructed based on ΔSsPep, and the levels of virulence of the wild-type (WT) and ΔSsPep/ΔSsPspC were compared in a mouse experimental infection model. We demonstrated that the double mutant ΔSsPep/ΔSsPspC was less virulent than the WT, and could induce a noticeable antibody response. Analysis of IgG subclasses (IgG1 and IgG2a) indicated that both Th1 and Th2 responses were induced by ΔSsPep/ΔSsPspC, although the IgG2a (Th1) response predominated over the IgG1 (Th2) response. Moreover, ΔSsPep/ΔSsPspC could confer 90% protective efficacy against challenge with a lethal dose of fully virulent S. suis 2. Taken together, these data demonstrate that ΔSsPep/ΔSsPspC can be used as an effective live vaccine and provide a novel strategy against infection of S. suis 2. Copyright © 2014 Elsevier GmbH. All rights reserved.

Succession of splicing regulatory elements determines cryptic 5΄ss functionality

PubMed Central

Brillen, Anna-Lena; Schöneweis, Katrin; Walotka, Lara; Hartmann, Linda; Müller, Lisa; Ptok, Johannes; Kaisers, Wolfgang; Poschmann, Gereon; Stühler, Kai; Buratti, Emanuele

2017-01-01

Abstract A critical step in exon definition is the recognition of a proper splice donor (5΄ss) by the 5’ end of U1 snRNA. In the selection of appropriate 5΄ss, cis-acting splicing regulatory elements (SREs) are indispensable. As a model for 5΄ss recognition, we investigated cryptic 5΄ss selection within the human fibrinogen Bβ-chain gene (FGB) exon 7, where we identified several exonic SREs that simultaneously acted on up- and downstream cryptic 5΄ss. In the FGB exon 7 model system, 5΄ss selection iteratively proceeded along an alternating sequence of U1 snRNA binding sites and interleaved SREs which in principle supported different 3’ exon ends. Like in a relay race, SREs either suppressed a potential 5΄ss and passed the splicing baton on or splicing actually occurred. From RNA-Seq data, we systematically selected 19 genes containing exons with silent U1 snRNA binding sites competing with nearby highly used 5΄ss. Extensive SRE analysis by different algorithms found authentic 5΄ss significantly more supported by SREs than silent U1 snRNA binding sites, indicating that our concept may permit generalization to a model for 5΄ss selection and 3’ exon end definition. PMID:28039323

Micro friction stir lap welding of AISI 430 ferritic stainless steel: a study on the mechanical properties, microstructure, texture and magnetic properties

NASA Astrophysics Data System (ADS)

Mostaan, Hossein; Safari, Mehdi; Bakhtiari, Arash

2018-04-01

In this study, the effect of friction stir welding of AISI 430 (X6Cr17, material number 1.4016) ferritic stainless steel is examined. Two thin sheets with dimensions of 0.4 × 50 × 200 mm3 are joined in lap configuration. Optical microscopy and field emission electron microscopy were used in order to microstructural evaluations and fracture analysis, respectively. Tensile test and microhardness measurements are employed in order to study the mechanical behaviors of welds. Also, vibrational sample magnetometry (VSM) is employed for characterizing magnetic properties of welded samples. Texture analysis is carried out in order to clarify the change mechanism of magnetic properties in the welded area. The results show that AISI 430 sheets are successfully joined considering both, the appearance of the welding bead and the strength of the welded joint. It is found that by friction stir welding of AISI 430 sheets, texture components with easy axes magnetization have been replaced by texture components with harder magnetization axes. VSM analysis showed that friction stir welding leads to increase in residual induction (Br) and coercivity (Hc). This increase is attributed to the grain refining due the friction stir welding and formation of texture components with harder axes of magnetizations.

Lactic acid bacteria increase antiallergic effect of Artemisia princeps pampanini SS-1.

PubMed

Lee, Seung-Hoon; Shin, Yong-Wook; Bae, Eun-Ah; Lee, Bomi; Min, Sungwon; Baek, Nam-In; Chung, Hae-Gon; Kim, Nam-Jae; Kim, Dong-Hyun

2006-09-01

Artemisia princeps Pampanini, which is called Ssajuarissuk in Korean (SS-1), was fermented with lactic acid bacteria (LAB) and their passive cutaneous anaphylaxis reaction-inhibitory activity was investigated. Of these fermented agents, SS-1 extract fermented with Bifidobacterium infantis K-525 (F-SS-1) most effectively inhibited the release of P-hexosamindase from RBL-2H3 cells induced IgE. In IgE-induced RBL-2H3 cells, F-SS-1 inhibited proinflammatory cytokines IL-6 and TNF-alpha mRNA expression. Oral administration of SS-1 and F-SS-1 to mice inhibited passive cutaneous anaphylaxis (PCA) reaction induced by IgE and scratching behaviors induced by compound 48/80. The inhibitory activity of F-SS-1 against scratching behaviors was more effective than that of SS-1. These findings suggest that the fermentation of SS-1 with LAB can increase its antiallergic activity.

Effects of gaseous nitriding AISI4140 alloy steel on corrosion and hardness properties

NASA Astrophysics Data System (ADS)

Tamil Moli, L.; Wahab, N.; Gopinathan, M.; Karmegam, K.; Maniyarasi, M.

2016-10-01

Corrosion is one of the major problems in the industry especially on machinery since it weakens the structure of the machinery part and causes the mechanical failure. This will stop the production and increase the maintenance cost. In this study, the corrosion behaviour of gas nitriding on a screw press machine shaft made from AISI 4140 steel was investigated. Pitting corrosion was identified as a major cause of the shaft failure and this study was conducted to improve the corrosion resistance on the AISI 4140 alloy steel shaft by gas nitriding as a surface hardening treatment. Gas nitriding was performed with composition of 15% ammonia and 85% nitrogen at temperatures of 525 °C, 550 °C and 575 °C and with the soaking time of 30, 45 and 60 minutes, respectively. The samples were prepared as rectangular sized of 30mm x 12mm x 3mm for immersion testing. The results showed that corrosion rate of untreated samples was 77% higher compared to the nitrided samples. It was also found that hardness of the nitrided samples was higher than untreated sample. All in all, it can be concluded that gaseous nitriding can significantly improve the surface hardness and the corrosion resistance of the shaft made of AISI 4140 alloy steel, hence reduces the pitting that is the root cause of failure.

AFM surface imaging of AISI D2 tool steel machined by the EDM process

NASA Astrophysics Data System (ADS)

Guu, Y. H.

2005-04-01

The surface morphology, surface roughness and micro-crack of AISI D2 tool steel machined by the electrical discharge machining (EDM) process were analyzed by means of the atomic force microscopy (AFM) technique. Experimental results indicate that the surface texture after EDM is determined by the discharge energy during processing. An excellent machined finish can be obtained by setting the machine parameters at a low pulse energy. The surface roughness and the depth of the micro-cracks were proportional to the power input. Furthermore, the AFM application yielded information about the depth of the micro-cracks is particularly important in the post treatment of AISI D2 tool steel machined by EDM.

Mechanisms for RNA capture by ssDNA viruses: grand theft RNA.

PubMed

Stedman, Kenneth

2013-06-01

Viruses contain three common types of packaged genomes; double-stranded DNA (dsDNA), RNA (mostly single and occasionally double stranded) and single-stranded DNA (ssDNA). There are relatively straightforward explanations for the prevalence of viruses with dsDNA and RNA genomes, but the evolutionary basis for the apparent success of ssDNA viruses is less clear. The recent discovery of four ssDNA virus genomes that appear to have been formed by recombination between co-infecting RNA and ssDNA viruses, together with the high mutation rate of ssDNA viruses provide possible explanations. RNA-DNA recombination allows ssDNA viruses to access much broader sequence space than through nucleotide substitution and DNA-DNA recombination alone. Multiple non-exclusive mechanisms, all due to the unique replication of ssDNA viruses, are proposed for this unusual RNA capture. RNA capture provides an explanation for the evolutionary success of the ssDNA viruses and may help elucidate the mystery of integrated RNA viruses in viral and cellular DNA genomes.

Wear Evaluation of AISI 4140 Alloy Steel with WC/C Lamellar Coatings Sliding Against EN 8 Using Taguchi Method

NASA Astrophysics Data System (ADS)

Kadam, Nikhil Rajendra; Karthikeyan, Ganesarethinam

2016-10-01

The purpose of the experiments in this paper is to use the Taguchi methods to investigate the wear of WC/C coated nitrided AISI 4140 alloy steel. A study of lamellar WC/C coating which were deposited by a physical vapor deposition on nitrided AISI 4140 alloy steel. The investigation includes wear evaluation using Pin-on-disk configuration. When WC/C coated AISI 4140 alloy steel slides against EN 8 steel, it was found that carbon-rich coatings show much lower wear of the countersurface than nitrogen-rich coatings. The results were correlated with the properties determined from tribological and mechanical characterization, therefore by probably selecting the proper processing parameters the deposition of WC/C coating results in decreasing the wear rate of the substrate which shows a potential for tribological application.

Biosecurity and Health Monitoring at the Zebrafish International Resource Center

PubMed Central

Varga, Zoltán M.; Kent, Michael L.

2016-01-01

Abstract The Zebrafish International Resource Center (ZIRC) is a repository and distribution center for mutant, transgenic, and wild-type zebrafish. In recent years annual imports of new zebrafish lines to ZIRC have increased tremendously. In addition, after 15 years of research, we have identified some of the most virulent pathogens affecting zebrafish that should be avoided in large production facilities, such as ZIRC. Therefore, while importing a high volume of new lines we prioritize safeguarding the health of our in-house fish colony. Here, we describe the biosecurity and health-monitoring program implemented at ZIRC. This strategy was designed to prevent introduction of new zebrafish pathogens, minimize pathogens already present in the facility, and ensure a healthy zebrafish colony for in-house uses and shipment to customers. PMID:27031282

Wear Characteristics of Ni-Based Hardfacing Alloy Deposited on Stainless Steel Substrate by Laser Cladding

NASA Astrophysics Data System (ADS)

Awasthi, Reena; Limaye, P. K.; Kumar, Santosh; Kushwaha, Ram P.; Viswanadham, C. S.; Srivastava, Dinesh; Soni, N. L.; Patel, R. J.; Dey, G. K.

2015-03-01

In this study, dry sliding wear characteristics of the Ni-based hardfacing alloy (Ni-Mo-Cr-Si) deposited on stainless steel SS316L substrate by laser cladding have been presented. Dry sliding wear behavior of the laser clad layer was evaluated against two different counter bodies, AISI 52100 chromium steel (~850 VHN) and tungsten carbide ball (~2200 VHN) to study both adhesive and abrasive wear characteristics, in comparison with the substrate SS316L using ball on plate reciprocating wear tester. The wear resistance was evaluated as a function of load and sliding speed for a constant sliding amplitude and sliding distance. The wear mechanisms were studied on the basis of wear surface morphology and microchemical analysis of the wear track using SEM-EDS. Laser clad layer of Ni-Mo-Cr-Si on SS316L exhibited much higher hardness (~700 VHN) than that of substrate SS316L (~200 VHN). The laser clad layer exhibited higher wear resistance as compared to SS316L substrate while sliding against both the counterparts. However, the improvement in the wear resistance of the clad layer as compared to the substrate was much higher while sliding against AISI 52100 chromium steel than that while sliding against WC, at the same contact stress intensity.

A novel protein elicitor (SsCut) from Sclerotinia sclerotiorum induces multiple defense responses in plants.

PubMed

Zhang, Huajian; Wu, Qun; Cao, Shun; Zhao, Tongyao; Chen, Ling; Zhuang, Peitong; Zhou, Xiuhong; Gao, Zhimou

2014-11-01

In this study, we report the cloning of the SsCut gene encoding cutinase from Sclerotinia sclerotiorum. We isolated a 609-bp cDNA encoding a polypeptide of 202 amino acids with a molecular weight of 20.4 kDa. Heterologous expression of SsCut in Escherichia coli (His-SsCut) caused the formation of lesions in tobacco that closely resembled hypersensitive response lesions. Mutational analysis identified the C-terminal-half peptide and the same amino acids indispensable for both enzyme and elicitor activity. His-SsCut was caused cell death in Arabidopsis, soybean (Glycine max), oilseed rape (Brassica napus), rice (Oryza sativa), maize (Zea mays), and wheat (Triticum aestivum), indicating that both dicot and monocot species are responsive to the elicitor. Furthermore, the elicitation of tobacco was effective in the induction of the activities of hydrogen peroxide, phenylalanine ammonia-lyase, peroxides, and polyphenol oxidase. His-SsCut-treated plants exhibited enhanced resistance as indicated by a significant reduction in the number and size of S. sclerotiorum, Phytophthora sojae, and P. nicotianae lesions on leaves relative to controls. Real-time PCR results indicated that the expression of defense-related genes and genes involved in signal transduction were induced by His-SsCut. Our results demonstrate that SsCut is an elicitor that triggers defense responses in plants and will help to clarify its relationship to downstream signaling pathways that induce defense responses.

Associations between salivary gland histopathologic diagnoses and phenotypic features of Sjögren’s Syndrome (SS) among 1726 registry participants

PubMed Central

Daniels, Troy E.; Cox, Darren; Shiboski, Caroline H.; Schiødt, Morten; Wu, Ava; Lanfranchi, Hector; Umehara, Hisanori; Zhao, Yan; Challacombe, Stephen; Lam, Mi Y.; DeSouza, Yvonne; Schiødt, Julie; Holm, Helena; Bisio, Patricia A. M.; Gandolfo, Mariana S.; Sawaki, Toshioki; Li, Mengtao; Zhang, Wen; Varghese-Jacob, Beni; Ibsen, Per; Keszler, Alicia; Kurose, Nozomu; Nojima, Takayuki; Odell, Edward; Criswell, Lindsey A.; Jordan, Richard; Greenspan, John S.

2011-01-01

Objectives The Sjögren’s International Collaborative Clinical Alliance (SICCA) is an ongoing NIH-funded registry whose cohort ranges from those with symptoms of possible Sjögren’s syndrome (SS) to those with obvious disease. Using this database we examined associations between labial salivary gland (LSG) histopathology and other phenotypic features of SS. Methods LSG biopsy specimens from SICCA participants underwent protocol-directed histopathological assessments. Among 1726 LSG specimens exhibiting any pattern of sialadenitis, we compared biopsy diagnoses against concurrent salivary, ocular and serological assessments. Results LSG specimens included 61% with focal lymphocytic sialadenitis, (FLS; 66% of which had focus scores [FS] ≥ 1 per 4 mm2) and 38% with non-specific or sclerosing chronic sialadenitis (NS/SCS). FS ≥ 1 was strongly associated with positive serum anti-SS-A/-B, rheumatoid factor and the ocular component of SS, but not with symptoms of dry mouth or eyes. Those with positive anti-SS-A/-B were 9 times more likely to have a FS ≥ 1 (95% CI: 7.4; 11.9) than FS<1 or another pattern, while those with unstimulated whole salivary flow < 0.1 ml/min were only 2 times more likely to have a FS ≥ 1 (95% CI:1.7; 2.8) than FS<1 or another pattern, while controlling for other phenotypic features of SS. Conclusions Distinguishing FLS from NS/SCS is essential in assessing LSG biopsies, before determining FS. A diagnosis of FLS with FS ≥ 1 per 4 mm2, as compared to FLS with FS< 1 or with NS/SCS, was strongly associated with the ocular and serological components of SS and reflects SS autoimmunity. PMID:21480190

Synthesis and characterization of PEG-P(MAA-SS-VCL) nanoparticles

NASA Astrophysics Data System (ADS)

Yu, L. L.; Yang, K.; Mu, R. H.; Zhang, N.; Su, L.

2016-07-01

The PEG-P(MAA-SS-VCL) nanoparticles were obtained using disulfide containing dimethacrylate (SS) as cross-linking agent, using polyethylene glycol methyl acrylate (PEGMA), N-Vinyl-ε-caprolactam (VCL), and methacrylic acid (MAA) as monomers via homogeneous polymerization in aqueous. The PEG-P(MAA-SS-VCL) nanoparticles were characterized by FT-IR and TGA. The particle size and morphology variation in different environments were detected by dynamic light scattering (DLS) and scanning electron microscopy (SEM). It is the very method that PEG-P(MAA-SS-VCL) nanoparticles can be obtained in this study.

Statistical and Graphical Assessment of Circumferential and Radial Hardness Variation of AISI 4140, AISI 1020 and AA 6082 Aluminum Alloy

PubMed Central

Al-Khalid, Hamad; Alaskari, Ayman; Oraby, Samy

2011-01-01

Hardness homogeneity of the commonly used structural ferrous and nonferrous engineering materials is of vital importance in the design stage, therefore, reliable information regarding material properties homogeneity should be validated and any deviation should be addressed. In the current study the hardness variation, over wide spectrum radial locations of some ferrous and nonferrous structural engineering materials, was investigated. Measurements were performed over both faces (cross-section) of each stock bar according to a pre-specified stratified design, ensuring the coverage of the entire area both in radial and circumferential directions. Additionally the credibility of the apparatus and measuring procedures were examined through a statistically based calibration process of the hardness reference block. Statistical and response surface graphical analysis are used to examine the nature, adequacy and significance of the measured hardness values. Calibration of the apparatus reference block proved the reliability of the measuring system, where no strong evidence was found against the stochastic nature of hardness measures over the various stratified locations. Also, outlier elimination procedures were proved to be beneficial only at fewer measured points. Hardness measurements showed a dispersion domain that is within the acceptable confidence interval. For AISI 4140 and AISI 1020 steels, hardness is found to have a slight decrease trend as the diameter is reduced, while an opposite behavior is observed for AA 6082 aluminum alloy. However, no definite significant behavior was noticed regarding the effect of the sector sequence (circumferential direction). PMID:28817030

Statistical and Graphical Assessment of Circumferential and Radial Hardness Variation of AISI 4140, AISI 1020 and AA 6082 Aluminum Alloy.

PubMed

Al-Khalid, Hamad; Alaskari, Ayman; Oraby, Samy

2011-12-23

Hardness homogeneity of the commonly used structural ferrous and nonferrous engineering materials is of vital importance in the design stage, therefore, reliable information regarding material properties homogeneity should be validated and any deviation should be addressed. In the current study the hardness variation, over wide spectrum radial locations of some ferrous and nonferrous structural engineering materials, was investigated. Measurements were performed over both faces (cross-section) of each stock bar according to a pre-specified stratified design, ensuring the coverage of the entire area both in radial and circumferential directions. Additionally the credibility of the apparatus and measuring procedures were examined through a statistically based calibration process of the hardness reference block. Statistical and response surface graphical analysis are used to examine the nature, adequacy and significance of the measured hardness values. Calibration of the apparatus reference block proved the reliability of the measuring system, where no strong evidence was found against the stochastic nature of hardness measures over the various stratified locations. Also, outlier elimination procedures were proved to be beneficial only at fewer measured points. Hardness measurements showed a dispersion domain that is within the acceptable confidence interval. For AISI 4140 and AISI 1020 steels, hardness is found to have a slight decrease trend as the diameter is reduced, while an opposite behavior is observed for AA 6082 aluminum alloy. However, no definite significant behavior was noticed regarding the effect of the sector sequence (circumferential direction).

Mechanism of the formation of the RecA-ssDNA nucleoprotein filament structure: a coarse-grained approach.

PubMed

Mukherjee, Goutam; Pal, Arumay; Levy, Yaakov

2017-11-21

In prokaryotes, the RecA protein catalyzes the repair and strand exchange of double-stranded DNA. RecA binds to single-stranded DNA (ssDNA) and forms a presynaptic complex in which the protein polymerizes around the ssDNA to form a right-handed helical nucleoprotein filament structure. In the present work, the mechanism for the formation of the RecA-ssDNA filament structure is modeled using coarse-grained molecular dynamics simulations. Information from the X-ray structure was used to model the protein itself but not its interactions; the interactions between the protein and the ssDNA were modeled solely by electrostatic, aromatic, and repulsive energies. For the present study, the monomeric, dimeric, and trimeric units of RecA and 4, 8, and 11 NT-long ssDNA, respectively, were studied. Our results indicate that monomeric RecA is not sufficient for nucleoprotein filament formation; rather, dimeric RecA is the elementary binding unit, with higher multimeric units of RecA facilitating filament formation. Our results reveal that loop region flexibility at the primary binding site of RecA is essential for it to bind the incoming ssDNA, that the aromatic residues present in the loop region play an important role in ssDNA binding, and that ATP may play a role in guiding the ssDNA by changing the electrostatic potential of the RecA protein.

BER analysis of SS-WDM based FSO system for Vellore weather conditions

NASA Astrophysics Data System (ADS)

Prabu, K.; Charanya, S.; Jain, Mehul; Guha, Debapriya

2017-11-01

Spectrum Slicing Wavelength Division Multiplexing (SS-WDM) has been advanced to boost the long distance communication in FSO channel which assists immense bit rate due to its high capacity and efficiency. It is a substitute to WDM systems having multiple coherent lasers with different wavelengths which is expensive. This paper is subjected to investigate the characteristics and quality of communication links of data rate 1.56 GB/s and wavelength of 1550 nm. The SS-WDM technique has been inspected for 4, 8 and 16 channels to increase the performance of communication under various weather conditions. The proposed model is susceptible to system degradation due to turbulences where wind velocity, refractive index and height of buildings have been majorly focused. A case study has been experimented on how the height of buildings around VIT, Vellore campus interfere the transmission of light in free space. Based on the above study, the results shows that the benefits of spectrum slicing wavelength division multiplexing (SS-WDM) have been worked up on for the climatic conditions which enhance performance of system. Moreover, the graphs plotted against bit error rate (BER), attenuation and distance makes the analysis better which highlights the characteristic features of SS-WDM.

VizieR Online Data Catalog: IN-SYNC. III. Radial velocities of IC348 stars (Cottaar+, 2015)

NASA Astrophysics Data System (ADS)

Cottaar, M.; Covey, K. R.; Foster, J. B.; Meyer, M. R.; Tan, J. C.; Nidever, D. L.; Drew Chojnowski, S.; da Rio, N.; Flaherty, K. M.; Frinchaboy, P. M.; Majewski, S.; Skrutskie, M. F.; Wilson, J. C.; Zasowski, G.

2015-11-01

Cottaar et al. (Paper I, 2014, J/ApJ/794/125) describes the analysis of the high-resolution near-infrared spectra obtained by the APOGEE multi-object spectrograph from stars in IC 348, NGC 1333, NGC 2264, and Orion A as part of the INfrared Spectroscopy of Young Nebulous Clusters (IN-SYNC) ancillary program. Using radial velocities determined from APOGEE spectra of 380 likely cluster members, we have measured the radial velocity distribution of the young (2-6Myr) cluster IC 348. (2 data files).

Nanotribological response of a plasma nitrided bio-steel.

PubMed

Samanta, Aniruddha; Chakraborty, Himel; Bhattacharya, Manjima; Ghosh, Jiten; Sreemany, Monjoy; Bysakh, Sandip; Rane, Ramkrishna; Joseph, Alphonsa; Jhala, Ghanshyam; Mukherjee, Subroto; Das, Mitun; Mukhopadhyay, Anoop K

2017-01-01

AISI 316L is a well known biocompatible, austenitic stainless steel (SS). It is thus a bio-steel. Considering its importance as a bio-prosthesis material here we report the plasma nitriding of AISI 316L (SS) followed by its microstructural and nanotribological characterization. Plasma nitriding of the SS samples was carried out in a plasma reactor with a hot wall vacuum chamber. For ease of comparison these plasma nitrided samples were termed as SSPN. The experimental results confirmed the formations of an embedded nitrided metal layer zone (ENMLZ) and an interface zone (IZ) between the ENMLZ and the unnitrided bulk metallic layer zone (BMLZ) in the SSPN sample. These ENMLZ and IZ in the SSPN sample were richer in iron nitride (FeN) chromium nitride (CrN) along with the austenite phase. The results from nanoindentation, microscratch, nanoscratch and sliding wear studies confirmed that the static contact deformation resistance, the microwear, nanowear and sliding wear resistance of the SSPN samples were much better than those of the SS samples. These results were explained in terms of structure-property correlations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Structure/property (constitutive and dynamic strength/damage) characterization of additively manufactured 316L SS

NASA Astrophysics Data System (ADS)

Gray, G. T., III; Livescu, V.; Rigg, P. A.; Trujillo, C. P.; Cady, C. M.; Chen, S. R.; Carpenter, J. S.; Lienert, T. J.; Fensin, S.

2015-09-01

For additive manufacturing (AM), the certification and qualification paradigm needs to evolve as there exists no "ASTM-type" additive manufacturing certified process or AM-material produced specifications. Accordingly, utilization of AM materials to meet engineering applications requires quantification of the constitutive properties of these evolving materials in comparison to conventionally-manufactured metals and alloys. Cylinders of 316L SS were produced using a LENS MR-7 laser additive manufacturing system from Optomec (Albuquerque, NM) equipped with a 1kW Yb-fiber laser. The microstructure of the AM-316L SS is detailed in both the as-built condition and following heat-treatments designed to obtain full recrystallization. The constitutive behavior as a function of strain rate and temperature is presented and compared to that of nominal annealed wrought 316L SS plate. The dynamic damage evolution and failure response of all three materials was probed using flyer-plate impact driven spallation experiments at a peak stress of 4.5 GPa to examine incipient spallation response. The spall strength of AM-produced 316L SS was found to be very similar for the peak shock stress studied to that of annealed wrought or AM-316L SS following recrystallization. The damage evolution as a function of microstructure was characterized using optical metallography.

[111In-DOTA]LTT-SS28, a first pansomatostatin radioligand for in vivo targeting of somatostatin receptor-positive tumors.

PubMed

Maina, Theodosia; Cescato, Renzo; Waser, Beatrice; Tatsi, Aikaterini; Kaloudi, Aikaterini; Krenning, Eric P; de Jong, Marion; Nock, Berthold A; Reubi, Jean Claude

2014-08-14

Radiolabeled pansomatostatin-like analogues are expected to enhance the diagnostic sensitivity and to expand the clinical indications of currently applied sst2-specific radioligands. In this study, we present the somatostatin mimic [DOTA]LTT-SS28 {[(DOTA)Ser1,Leu8,D-Trp22,Tyr25]SS28} and its 111In radioligand. [DOTA]LTT-SS28 exhibited a pansomatostatin-like profile binding with high affinity to all five hsst1-hsst5 subtypes (IC50 values in the lower nanomolar range). Furthermore, [DOTA]LTT-SS28 behaved as an agonist at hsst2, hsst3, and hsst5, efficiently stimulating internalization of the three receptor subtypes. Radioligand [111In-DOTA]LTT-SS28 showed good stability in the mouse bloodstream. It displayed strong and specific uptake in AR42J tumors 4 h postinjection (9.3±1.6% ID/g vs 0.3±0.0% ID/g during sst2 blockade) in mice. Significant and specific uptake was also observed in HEK293-hsst2-, HEK293-hsst3-, and HEK293-hsst5-expressing tumors (4.43±1.5, 4.88±1.1, and <3% ID/g, respectively, with values of <0.5% ID/g during receptor blockade). In conclusion, the somatostatin mimic [111In-DOTA]LTT-SS28 specifically localizes in sst2-, sst3-, and sst5-expressing xenografts in mice showing promise for multi-sst1-sst5 targeted tumor imaging.

Diversity of maize kernels from a breeding program for protein quality III: Ionome profiling

USDA-ARS?s Scientific Manuscript database

Densities of single and multiple macro- and micronutrients have been estimated in mature kernels of 1,348 accessions in 13 maize genotypes. The germplasm belonged to stiff stalk (SS) and non-stiff stalk (NS) heterotic groups (HG) with one (S1) to four (S4) years of inbreeding (IB), or open pollinati...

Simultaneous IUE and Ground Based Observations of SS Cygni and HL Canis Majoris

NASA Astrophysics Data System (ADS)

Mansperger, C. S.; Kaitchuck, R. H.; Garnavich, P.; Dinshaw, N.

1993-05-01

SS Cyg and HL CMa were observed by IUE for three consecutive nights in November of 1992. During the first two nights, simultaneous photometric ground based observations of SS Cyg were made at the Ball State University Observatory. SS Cyg and HL CMa were observed simultaneously with the 90-inch telescope at the Steward Observatory on the last two nights of this run. These spectroscopic observations covered the wavelength range of 4100 Angstroms to 5000 Angstroms, while the spectra taken with the short wavelength camera on IUE resulted in wavelength coverage from 1150 Angstroms to 1980 Angstroms. SS Cyg is a U Gem type dwarf nova with an orbital period of 6.6 hours. Good simultaneous UV and optical orbital coverage was obtained for this system. HL CMa is a Z Cam type dwarf nova with an outburst period of 18 days. The AAVSO reports that this system was in outburst 4 days after the observing run. Therefore, HL CMa may have been in a preoutburst state during these observations. The C IV and H \\beta emission lines appeared to have weakened during this time.

APOBEC3G Interacts with ssDNA by Two Modes: AFM Studies

NASA Astrophysics Data System (ADS)

Shlyakhtenko, Luda S.; Dutta, Samrat; Banga, Jaspreet; Li, Ming; Harris, Reuben S.; Lyubchenko, Yuri L.

2015-10-01

APOBEC3G (A3G) protein has antiviral activity against HIV and other pathogenic retroviruses. A3G has two domains: a catalytic C-terminal domain (CTD) that deaminates cytidine, and a N-terminal domain (NTD) that binds to ssDNA. Although abundant information exists about the biological activities of A3G protein, the interplay between sequence specific deaminase activity and A3G binding to ssDNA remains controversial. We used the topographic imaging and force spectroscopy modalities of Atomic Force Spectroscopy (AFM) to characterize the interaction of A3G protein with deaminase specific and nonspecific ssDNA substrates. AFM imaging demonstrated that A3G has elevated affinity for deaminase specific ssDNA than for nonspecific ssDNA. AFM force spectroscopy revealed two distinct binding modes by which A3G interacts with ssDNA. One mode requires sequence specificity, as demonstrated by stronger and more stable complexes with deaminase specific ssDNA than with nonspecific ssDNA. Overall these observations enforce prior studies suggesting that both domains of A3G contribute to the sequence specific binding of ssDNA.

APOBEC3G Interacts with ssDNA by Two Modes: AFM Studies.

PubMed

Shlyakhtenko, Luda S; Dutta, Samrat; Banga, Jaspreet; Li, Ming; Harris, Reuben S; Lyubchenko, Yuri L

2015-10-27

APOBEC3G (A3G) protein has antiviral activity against HIV and other pathogenic retroviruses. A3G has two domains: a catalytic C-terminal domain (CTD) that deaminates cytidine, and a N-terminal domain (NTD) that binds to ssDNA. Although abundant information exists about the biological activities of A3G protein, the interplay between sequence specific deaminase activity and A3G binding to ssDNA remains controversial. We used the topographic imaging and force spectroscopy modalities of Atomic Force Spectroscopy (AFM) to characterize the interaction of A3G protein with deaminase specific and nonspecific ssDNA substrates. AFM imaging demonstrated that A3G has elevated affinity for deaminase specific ssDNA than for nonspecific ssDNA. AFM force spectroscopy revealed two distinct binding modes by which A3G interacts with ssDNA. One mode requires sequence specificity, as demonstrated by stronger and more stable complexes with deaminase specific ssDNA than with nonspecific ssDNA. Overall these observations enforce prior studies suggesting that both domains of A3G contribute to the sequence specific binding of ssDNA.

APOBEC3G Interacts with ssDNA by Two Modes: AFM Studies

PubMed Central

Shlyakhtenko, Luda S.; Dutta, Samrat; Banga, Jaspreet; Li, Ming; Harris, Reuben S.; Lyubchenko, Yuri L.

2015-01-01

APOBEC3G (A3G) protein has antiviral activity against HIV and other pathogenic retroviruses. A3G has two domains: a catalytic C-terminal domain (CTD) that deaminates cytidine, and a N-terminal domain (NTD) that binds to ssDNA. Although abundant information exists about the biological activities of A3G protein, the interplay between sequence specific deaminase activity and A3G binding to ssDNA remains controversial. We used the topographic imaging and force spectroscopy modalities of Atomic Force Spectroscopy (AFM) to characterize the interaction of A3G protein with deaminase specific and nonspecific ssDNA substrates. AFM imaging demonstrated that A3G has elevated affinity for deaminase specific ssDNA than for nonspecific ssDNA. AFM force spectroscopy revealed two distinct binding modes by which A3G interacts with ssDNA. One mode requires sequence specificity, as demonstrated by stronger and more stable complexes with deaminase specific ssDNA than with nonspecific ssDNA. Overall these observations enforce prior studies suggesting that both domains of A3G contribute to the sequence specific binding of ssDNA. PMID:26503602

Quest Trial Q348: Evaluation of WaMoS II Data

DTIC Science & Technology

2013-04-01

and slam warning.” Quest Sea Trial Q348 page 7 “In July of 2011, as part of the 11gi project, DRDC acquired and installed a new WaMoS...Fourier series expansion was originally implemented to compare WaMoS II data to reference data of an airborne LIDAR scanner, which yielded very good

48 CFR 253.213 - Simplified acquisition procedures (SF's 18, 30, 44, 1165, 1449, and OF's 336, 347, and 348).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Simplified acquisition procedures (SF's 18, 30, 44, 1165, 1449, and OF's 336, 347, and 348). 253.213 Section 253.213 Federal... OF's 336, 347, and 348). (f) DoD uses the DD Form 1155, Order for Supplies or Services, instead of OF...

Guignardones P-S, New Meroterpenoids from the Endophytic Fungus Guignardia mangiferae A348 Derived from the Medicinal Plant Smilax glabra.

PubMed

Sun, Zhang-Hua; Liang, Fa-Liang; Wu, Wen; Chen, Yu-Chan; Pan, Qing-Ling; Li, Hao-Hua; Ye, Wei; Liu, Hong-Xin; Li, Sai-Ni; Tan, Guo-Hui; Zhang, Wei-Min

2015-12-21

Four new meroterpenoids, guignardones P-S (1-4), and three known analogues (5-7) were isolated from the endophytic fungal strain Guignardia mangiferae A348. Their structures were elucidated on the basis of spectroscopic analysis and single crystal X-ray diffraction. All the isolated compounds were evaluated for their inhibitory effects on SF-268, MCF-7, and NCI-H460 human cancer cell lines. Compounds 2 and 4 exhibited weak inhibitions of cell proliferation against MCF-7 cell line.

Kinetic Investigation and Wear Properties of Fe2B Layers on AISI 12L14 Steel

NASA Astrophysics Data System (ADS)

Keddam, M.; Ortiz-Dominguez, M.; Elias-Espinosa, M.; Arenas-Flores, A.; Zuno-Silva, J.; Zamarripa-Zepeda, D.; Gomez-Vargas, O. A.

2018-03-01

In the current study, the powder-pack boriding was applied to the AISI 12L14 steel in the temperature range 1123 K to 1273 K for an exposure time between 2 and 8 hours. The produced boride layer was composed of Fe2B with a sawtooth morphology. A diffusion model based on the integral method was applied to investigate the growth kinetics of Fe2B layers. As a main result, the boron diffusion coefficients in Fe2B were estimated by considering the principle of mass balance at the (Fe2B/substrate) interface with an inclusion of boride incubation times. The value of activation energy for boron diffusion in AISI 12L14 steel was estimated as 165 kJ mol-1 and compared with other values of activation energy found in the literature. An experimental validation of the present model was made by using four different boriding conditions. Furthermore, the Rockwell-C adhesion test was employed to assess the cohesion of boride layers to the base metal. The scratch and pin-on-disc tests were also carried out to analyze the effect of boriding on wear behavior of AISI 12L14 steel.

A three-dimensional thermal finite element analysis of AISI 304 stainless steel and copper dissimilar weldment

NASA Astrophysics Data System (ADS)

Singh, Gurdeep; Saxena, Ravindra K.; Pandey, Sunil

2018-04-01

The aim of this study to developed a 3-D thermal finite element model for dissimilar material welding of AISI-304 stainless steel and copper. Welding of similar material is widely studied using experimental and numerical methods but the problem becomes trivial for the welding of dissimilar materials especially in ferrous and nonferrous materials. Finite element analysis of dissimilar material welding is a cost-effective method for the understanding and analysis of the process. The finite element analysis has been performed to predict the heat affected zone and temperature distribution in AISI-304 stainless steel and copper dissimilar weldment using MSC Marc 2017®. Due to the difference in physical properties of these materials the behavior of heat affected zone and temperature distribution are perceived to be different. To verify the accuracy of the thermal finite element model, the welding process was simulated with butt-welded joints having same dimensions and parameters from Attarha and Far [1]. It is found from the study that the heat affected zone is larger in copper weld pads than in AISI 304 stainless steel due to large difference in thermal conductivity of these two weld pads.

SynBioSS-aided design of synthetic biological constructs.

PubMed

Kaznessis, Yiannis N

2011-01-01

We present walkthrough examples of using SynBioSS to design, model, and simulate synthetic gene regulatory networks. SynBioSS stands for Synthetic Biology Software Suite, a platform that is publicly available with Open Licenses at www.synbioss.org. An important aim of computational synthetic biology is the development of a mathematical modeling formalism that is applicable to a wide variety of simple synthetic biological constructs. SynBioSS-based modeling of biomolecular ensembles that interact away from the thermodynamic limit and not necessarily at steady state affords for a theoretical framework that is generally applicable to known synthetic biological systems, such as bistable switches, AND gates, and oscillators. Here, we discuss how SynBioSS creates links between DNA sequences and targeted dynamic phenotypes of these simple systems. Copyright © 2011 Elsevier Inc. All rights reserved.

RNA-processing proteins regulate Mec1/ATR activation by promoting generation of RPA-coated ssDNA.

PubMed

Manfrini, Nicola; Trovesi, Camilla; Wery, Maxime; Martina, Marina; Cesena, Daniele; Descrimes, Marc; Morillon, Antonin; d'Adda di Fagagna, Fabrizio; Longhese, Maria Pia

2015-02-01

Eukaryotic cells respond to DNA double-strand breaks (DSBs) by activating a checkpoint that depends on the protein kinases Tel1/ATM and Mec1/ATR. Mec1/ATR is activated by RPA-coated single-stranded DNA (ssDNA), which arises upon nucleolytic degradation (resection) of the DSB. Emerging evidences indicate that RNA-processing factors play critical, yet poorly understood, roles in genomic stability. Here, we provide evidence that the Saccharomyces cerevisiae RNA decay factors Xrn1, Rrp6 and Trf4 regulate Mec1/ATR activation by promoting generation of RPA-coated ssDNA. The lack of Xrn1 inhibits ssDNA generation at the DSB by preventing the loading of the MRX complex. By contrast, DSB resection is not affected in the absence of Rrp6 or Trf4, but their lack impairs the recruitment of RPA, and therefore of Mec1, to the DSB. Rrp6 and Trf4 inactivation affects neither Rad51/Rad52 association nor DSB repair by homologous recombination (HR), suggesting that full Mec1 activation requires higher amount of RPA-coated ssDNA than HR-mediated repair. Noteworthy, deep transcriptome analyses do not identify common misregulated gene expression that could explain the observed phenotypes. Our results provide a novel link between RNA processing and genome stability. © 2014 The Authors.

Finite Element Simulation and Experimental Verification of Internal Stress of Quenched AISI 4140 Cylinders

NASA Astrophysics Data System (ADS)

Liu, Yu; Qin, Shengwei; Hao, Qingguo; Chen, Nailu; Zuo, Xunwei; Rong, Yonghua

2017-03-01

The study of internal stress in quenched AISI 4140 medium carbon steel is of importance in engineering. In this work, the finite element simulation (FES) was employed to predict the distribution of internal stress in quenched AISI 4140 cylinders with two sizes of diameter based on exponent-modified (Ex-Modified) normalized function. The results indicate that the FES based on Ex-Modified normalized function proposed is better consistent with X-ray diffraction measurements of the stress distribution than FES based on normalized function proposed by Abrassart, Desalos and Leblond, respectively, which is attributed that Ex-Modified normalized function better describes transformation plasticity. Effect of temperature distribution on the phase formation, the origin of residual stress distribution and effect of transformation plasticity function on the residual stress distribution were further discussed.

On electrical resistivity of AISI D2 steel during various stages of cryogenic treatment

NASA Astrophysics Data System (ADS)

Lomte, Sachin Vijay; Gogte, Chandrashekhar Laxman; Peshwe, Dilip

2012-06-01

The effect of dislocation densities and residual stresses is well known in tool steels. Measurement of electrical resistivity in order to monitor dislocation densities or residual stresses has seldom been used in investigating the effect of cryogenic treatment on tool steels. Monitoring residual stresses during cryogenic treatment becomes important as it is directly related to changes due to cryogenic treatment of tool steels. For high carbon high chromium (HCHC- AISI D2) steels, not only wear resistance but dimensional stability is an important issue as the steels are extensively used in dies, precision measuring instruments. This work comprises of study of measurement of electrical resistivity of AISI D2 steel at various stages of cryogenic treatment. Use of these measurements in order to assess the dimensional stability of these steels is discussed in this paper.

A Simple Kinetic Model for the Growth of Fe2B Layers on AISI 1026 Steel During the Powder-pack Boriding

NASA Astrophysics Data System (ADS)

Flores-Rentería, M. A.; Ortiz-Domínguez, M.; Keddam, M.; Damián-Mejía, O.; Elias-Espinosa, M.; Flores-González, M. A.; Medina-Moreno, S. A.; Cruz-Avilés, A.; Villanueva-Ibañez, M.

2015-02-01

This work focused on the determination of boron diffusion coefficient through the Fe2B layers on AISI 1026 steel using a mathematical model. The suggested model solves the mass balance equation at the (Fe2B/substrate) interface. This thermochemical treatment was carried out in the temperature range of 1123-1273 K for a treatment time ranging from 2 to 8 h. The generated boride layers were characterized by different experimental techniques such as light optical microscopy, scanning electron microscopy, XRD analysis and the Daimler-Benz Rockwell-C indentation technique. As a result, the boron activation energy for AISI 1026 steel was estimated as 178.4 kJ/mol. Furthermore, this kinetic model was validated by comparing the experimental Fe2B layer thickness with the predicted one at a temperature of 1253 K for 5 h of treatment. A contour diagram relating the layer thickness to the boriding parameters was proposed to be used in practical applications.

Controllable g5p-Protein-Directed Aggregation of ssDNA-Gold Nanoparticles

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

Lee, S.; Maye, M; Zhang, Y

We assembled single-stranded DNA (ssDNA) conjugated nanoparticles using the phage M13 gene 5 protein (g5p) as the molecular glue to bind two antiparallel noncomplementary ssDNA strands. The entire process was controlled tightly by the concentration of the g5p protein and the presence of double-stranded DNA. The g5p-ssDNA aggregate was disintegrated by hybridization with complementary ssDNA (C-ssDNA) that triggers the dissociation of the complex. Polyhistidine-tagged g5p was bound to nickel nitrilotriacetic acid (Ni2+-NTA) conjugated nanoparticles and subsequently used to coassemble the ssDNA-conjugated nanoparticles into multiparticle-type aggregates. Our approach offers great promise for designing biologically functional, controllable protein/nanoparticle composites.

Nitriding of AISI 4140 steel by a low energy broad ion source

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

Ochoa, E. A.; Figueroa, C. A.; Alvarez, F.

2006-11-15

A comprehensive study of the thermochemical nitriding process of steel AISI 4140 by low energy ion implantation (Kaufmann cell) is reported. Different times of implantation were employed and the studied samples were characterized by x-ray diffraction, in situ photoemission electron spectroscopy, scanning electron microscopy, and hardness (nanoindentation) measurements. The linear relationship between nitrogen content and hardness was verified. The structure of the nitrided layer was characterized yielding that the compound layer is formed by coarse precipitates, around small grains, constituted principally by {epsilon}-Fe{sub 2-3}N and {gamma}-Fe{sub 4}N phases and the diffusion zone is formed by fine precipitates, around big grainsmore » of the original martensitic phase, constituted principally by {gamma}-Fe{sub 4}N phase. Finally, a diffusion model for multiphase systems was applied to determine effective diffusion coefficients of nitrogen in the different phases.« less

On the Nature of the Compact Object in SS 433: Observational Evidence of X-ray Photon Index Saturation

NASA Astrophysics Data System (ADS)

Seifina, Elena; Titarchuk, Lev

2010-10-01

We present an analysis of the X-ray spectral properties observed from the black hole candidate (BHC) binary SS 433. We have analyzed Rossi X-ray Timing Explorer data from this source, coordinated with Green Bank Interferometer/RATAN-600. We show that SS 433 undergoes an X-ray spectral transition from the low hard state to the intermediate state (IS). We show that the X-ray broadband energy spectra during all spectral states are well fitted by a sum of the so-called bulk motion Comptonization (BMC) component and by two (broad and narrow) Gaussians for the continuum and line emissions, respectively. In addition to these spectral model components, we also find a strong feature that we identify as a "blackbody-like (BB)" component in which the color temperature is in the range of 4-5 keV in 24 IS spectra during the radio outburst decay in SS 433. Our observational results on the "high-temperature BB" bump lead us to suggest the presence of gravitationally redshifted annihilation line emission in this source. In fact, this spectral feature has been recently reproduced in Monte Carlo simulations by Laurent & Titarchuk. We have also established the photon index saturation at about 2.3 in index versus mass accretion correlation. This index-mass accretion correlation allows us to evaluate the low limit of the black hole (BH) mass of the compact object in SS 433, M_{{bh}}≳ 2 solar masses, using the scaling method using BHC GX 339 - 4 as a reference source. Our estimate of the BH mass in SS 433 is consistent with the recent BH mass measurement using the radial velocity measurements of the binary system by Hillwig & Gies, who find that Mx = (4.3 ± 0.8) solar masses. This is the smallest BH mass found up to now among all BH sources. Moreover, the index saturation effect versus mass accretion rate revealed in SS 433, as in a number of other BH candidates, is strong observational evidence for the presence of a BH in SS 433.

On the Nature of the Compact Object in SS 433. Observational Evidence of X-Ray Photon Index Saturation

NASA Technical Reports Server (NTRS)

Seifina, Elena; Titarchuk, Lev

2010-01-01

We present an analysis of the X-ray spectral properties observed from black hole , candidate (BHC) binary SS 433. We have analyzed Rossi X-ray Time Explorer (RXTE) data from this source, coordinated with Green Bank Interferometer/RATAN-600. We show that SS 433 undergoes a X-ray spectral transition from the low hard state (LHS) to the intermediate state (IS). We show that the X-ray broad-band energy spectra during all spectral states are well fit by a sum of so called "Bulk Motion Comptonization (BMC) component" and by two (broad and narrow) Gaussians for the continuum and line emissions respectively. In addition to these spectral model components we also find a strong feature that we identify as a" blackbody-like (BB)" component which color temperature is in the range of 4-5 keV in 24 IS spectra during the radio outburst decay in SS 433. Our observational results on the "high temperature BB" bump leads us to suggest the presence of gravitationally redshifted annihilation line emission in this source. In fact this spectral feature has been recently reproduced in Monte Carlo simulations by Laurent and Titarchuk. We have also established the photon index saturation at about 2.3 in index vs mass accretion correlation. This index-mass accretion correlation allows us to evaluate the low limit of black hole (BH) mass of compact object in SS 433, M(sub bh) approximately > 2 solar masses, using the scaling method using BHC GX 339-4 as a reference source. Our estimate of the BH mass in SS 433 is consistent with recent BH mass measurement using the radial-velocity measurements of the binary system by Hillwig & Gies who find that M(sub x)( = (4.3 +/- 0.8) solar masses. This is the smallest BH mass found up to now among all BH sources. Moreover, the index saturation effect versus mass accretion rate revealed in SS 433, like in a number of other BH candidates, is the strong observational evidence for the presence of a BH in SS 433.

High Resolution X-ray Spectroscopy and Star Formation: HETG Observations of the Pre-Main Sequence Stellar Cluster IC 348

NASA Astrophysics Data System (ADS)

Principe, David; Huenemoerder, David P.; Schulz, Norbert; Kastner, Joel H.; Weintraub, David; Preibisch, Thomas

2018-01-01

We present Chandra High Energy Transmission Grating (HETG) observations of the ∼3 Myr old pre-main sequence (pre-MS) stellar cluster IC 348. With 400-500 cluster members at a distance of ∼300 pc, IC 348 is an ideal target to observe a large number of X-ray sources in a single pointing and is thus an extremely efficient use of Chandra-HETG. High resolution X-ray spectroscopy offers a means to investigate detailed spectral characteristic of X-ray emitting plasmas and their surrounding environments. We present preliminary results where we compare X-ray spectral signatures (e.g., luminosity, temperature, column density, abundance) of the X-ray brightest pre-MS stars in IC 348 with spectral type, multiwavelength signatures of accretion, and the presence of circumstellar disks at multiple stages of pre-MS stellar evolution. Assuming all IC 348 members formed from the same primordial molecular cloud, any disparity between coronal abundances of individual members, as constrained by the identification and strength of emission lines, will constrain the source(s) of coronal chemical evolution at a stage of pre-MS evolution vital to the formation of planets.

A SCUBA-2 850-μm survey of protoplanetary discs in the IC 348 cluster

NASA Astrophysics Data System (ADS)

Cieza, L.; Williams, J.; Kourkchi, E.; Andrews, S.; Casassus, S.; Graves, S.; Schreiber, M. R.

2015-12-01

We present 850-μm observations of the 2-3 Myr cluster IC 348 in the Perseus molecular cloud using the SCUBA-2 camera on the James Clerk Maxwell Telescope. Our SCUBA-2 map has a diameter of 30 arcmin and contains ˜370 cluster members, including ˜200 objects with IR excesses. We detect a total of 13 discs. Assuming standard dust properties and a gas-to-dust-mass ratio of 100, we derive disc masses ranging from 1.5 to 16 MJUP. We also detect six Class 0/I protostars. We find that the most massive discs (MD > 3 MJUP; 850-μm flux > 10 mJy) in IC 348 tend to be transition objects according to the characteristic `dip' in their infrared spectral energy distributions (SEDs). This trend is also seen in other regions. We speculate that this could be an initial conditions effect (e.g. more massive discs tend to form giant planets that result in transition disc SEDs) and/or a disc evolution effect (the formation of one or more massive planets results in both a transition disc SED and a reduction of the accretion rate, increasing the lifetime of the outer disc). A stacking analysis of the discs that remain undetected in our SCUBA-2 observations suggests that their median 850-μm flux should be ≲1 mJy, corresponding to a disc mass ≲0.3 MJUP (gas plus dust) or ≲1 M⊕ of dust. While the available data are not deep enough to allow a meaningful comparison of the disc luminosity functions between IC 348 and other young stellar clusters, our results imply that disc masses exceeding the minimum-mass solar nebula are very rare (≲1per cent) at the age of IC 348, especially around very low-mass stars.

Evidence for two distinct KiSS genes in non-placental vertebrates that encode kisspeptins with different gonadotropin-releasing activities in fish and mammals.

PubMed

Felip, Alicia; Zanuy, Silvia; Pineda, Rafael; Pinilla, Leonor; Carrillo, Manuel; Tena-Sempere, Manuel; Gómez, Ana

2009-11-27

Kisspeptins, the products of KiSS-1 gene, have recently emerged as fundamental regulators of reproductive function in different mammalian and, presumably, non-mammalian species. To date, a single form of KiSS-1 has been described in mammals, and recently, in several fish species and Xenopus. We report herein the cloning and characterization of two distinct KiSS-like genes, namely, KiSS-1 and KiSS-2, in the teleost sea bass. While KiSS-1 encodes a peptide identical to rodent kisspeptin-10, the predicted KiSS-2 decapeptide diverges at 4 amino acids (FNFNPFGLRF). Genome database searches showed that both genes are present in non-placental vertebrate genomes. Indeed, phylogenetic and genome mapping analyses suggest that KiSS-1 and KiSS-2 are paralogous genes that originated by duplication of an ancestral gene, although KiSS-2 is lost in placental mammals. KiSS-1 and KiSS-2 mRNAs are present in brain and gonads of sea bass, medaka and zebrafish. Comparative functional studies demonstrated that KiSS-2 decapeptide was significantly more potent than KiSS-1 peptide in inducing LH and FSH secretion in sea bass. In contrast, KiSS-2 decapeptide only weakly elicited LH secretion in rats, whereas KiSS-1 peptide was maximally effective. Our data are the first to provide conclusive evidence for the existence of a second KiSS gene, KiSS-2, in non-placental vertebrates, whose product is likely to play a dominant stimulatory role in the regulation of the gonadotropic axis at least in teleosts.

Clinical characteristics of RA patients with secondary SS and association with joint damage.

PubMed

Brown, Lindsay E; Frits, Michelle L; Iannaccone, Christine K; Weinblatt, Michael E; Shadick, Nancy A; Liao, Katherine P

2015-05-01

Secondary SS (sSS) is a common extra-articular manifestation of RA. There are conflicting data regarding the association of sSS with worse joint damage. This study aims to characterize sSS patients in an RA cohort and study the association between sSS and joint damage. We conducted a cross-sectional study of RA patients with ≥1 year of follow-up at a large academic centre. Subjects with co-morbid diseases that can also result in sicca symptoms were excluded from the analysis. Subjects were considered to have sSS if they were reported as having sSS by their rheumatologist at recruitment into the cohort and had the diagnosis confirmed by chart review. The primary outcome was Sharp score using bilateral hand radiographs at recruitment. We constructed a linear regression model to determine the association of sSS status and Sharp score adjusted by age, gender, disease duration and ACPA and RF status. We studied 829 RA subjects, mean age 57 years, 83% female, mean RA duration 13 years, 74% seropositive; 85 subjects (10.3%) had sSS. We observed a female predominance (95.3%), longer mean disease duration (16.9 years) and higher frequency of RF or ACPA positive among patients with sSS and RA. Having sSS at baseline was associated with higher Sharp scores (P = 0.03), independent of age, gender, RA disease duration and seropositive disease. In our RA cohort, RA subjects with sSS had worse joint damage, suggesting that sSS is a marker of more aggressive disease. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Network Management and FDIR for SpaceWire Networks (N-MaSS)

NASA Astrophysics Data System (ADS)

Montano, Giuseppe; Jameux, David; Cook, Barry; Peel, Rodger; McCormick, Ecaterina; Walker, Paul; Kollias, Vangelis; Pogkas, Nikos

2014-08-01

The SpaceWire network management layer, which manages network topology and routing, is not yet standardised. This paper presents the European Space Agency (ESA) N-MaSS study, which focuses on implementation and standardisation of Fault Detection, Isolation and Recovery (FDIR) functions within the SpaceWire network management layer. N-MaSS provides an autonomous FDIR solution. It is defined at the SpaceWire network layer in order to achieve efficient re-use for heterogeneous missions, allowing for the incorporation of legacy equipment. The N-MaSS FDIR functions identify SpaceWire link and node failures and provide recovery using redundant nodes.This paper provides an overview of the overall N- MaSS study. In particular, the following topics are discussed: (a) how user requirements have been captured from the industry, SpaceWire Working Group and ESA; (b) how the N-MaSS architecture was organically shaped on the basis of the requirements captured; (c) how the N-MaSS concept is currently being implemented in a demonstrator and verified.

The Phage Lysin PlySs2 Decolonizes Streptococcus suis from Murine Intranasal Mucosa.

PubMed

Gilmer, Daniel B; Schmitz, Jonathan E; Thandar, Mya; Euler, Chad W; Fischetti, Vincent A

2017-01-01

Streptococcus suis infects pigs worldwide and may be zoonotically transmitted to humans with a mortality rate of up to 20%. S. suis has been shown to develop in vitro resistance to the two leading drugs of choice, penicillin and gentamicin. Because of this, we have pursued an alternative therapy to treat these pathogens using bacteriophage lysins. The bacteriophage lysin PlySs2 is derived from an S. suis phage and displays potent lytic activity against most strains of that species including serotypes 2 and 9. At 64 μg/ml, PlySs2 reduced multiple serotypes of S. suis by 5 to 6-logs within 1 hour in vitro and exhibited a minimum inhibitory concentration (MIC) of 32 μg/ml for a S. suis serotype 2 strain and 64 μg/ml for a serotype 9 strain. Using a single 0.1-mg dose, the colonizing S. suis serotype 9 strain was reduced from the murine intranasal mucosa by >4 logs; a 0.1-mg dose of gentamicin reduced S. suis by <3-logs. A combination of 0.05 mg PlySs2 + 0.05 mg gentamicin reduced S. suis by >5-logs. While resistance to gentamicin was induced after systematically increasing levels of gentamicin in an S. suis culture, the same protocol resulted in no observable resistance to PlySs2. Thus, PlySs2 has both broad and high killing activity against multiple serotypes and strains of S. suis, making it a possible tool in the control and prevention of S. suis infections in pigs and humans.

The Phage Lysin PlySs2 Decolonizes Streptococcus suis from Murine Intranasal Mucosa

PubMed Central

Gilmer, Daniel B.; Schmitz, Jonathan E.; Thandar, Mya; Euler, Chad W.; Fischetti, Vincent A.

2017-01-01

Streptococcus suis infects pigs worldwide and may be zoonotically transmitted to humans with a mortality rate of up to 20%. S. suis has been shown to develop in vitro resistance to the two leading drugs of choice, penicillin and gentamicin. Because of this, we have pursued an alternative therapy to treat these pathogens using bacteriophage lysins. The bacteriophage lysin PlySs2 is derived from an S. suis phage and displays potent lytic activity against most strains of that species including serotypes 2 and 9. At 64 μg/ml, PlySs2 reduced multiple serotypes of S. suis by 5 to 6-logs within 1 hour in vitro and exhibited a minimum inhibitory concentration (MIC) of 32 μg/ml for a S. suis serotype 2 strain and 64 μg/ml for a serotype 9 strain. Using a single 0.1-mg dose, the colonizing S. suis serotype 9 strain was reduced from the murine intranasal mucosa by >4 logs; a 0.1-mg dose of gentamicin reduced S. suis by <3-logs. A combination of 0.05 mg PlySs2 + 0.05 mg gentamicin reduced S. suis by >5-logs. While resistance to gentamicin was induced after systematically increasing levels of gentamicin in an S. suis culture, the same protocol resulted in no observable resistance to PlySs2. Thus, PlySs2 has both broad and high killing activity against multiple serotypes and strains of S. suis, making it a possible tool in the control and prevention of S. suis infections in pigs and humans. PMID:28046082

Alkalistable endo-β-1,4-xylanase production from a newly isolated alkalitolerant Penicillium sp. SS1 using agro-residues.

PubMed

Bajaj, Bijender Kumar; Sharma, Mukul; Sharma, Sunny

2011-09-01

Thermostable and alkalitolerant xylanases have got intense research focus due to their vast applications in various industries including pulp and paper, food, feed, textile, biofuel, etc. In the present investigation, a Penicillum sp. SS1 isolated from degrading woody material was found to produce moderately thermoactive and alkalistable endo-β-1,4-xylanase (xylanase). Maximum xylanase production was observed after fourth day of fermentation (43.84 IU/ml). The organism produced substantial quantities of xylanase using agricultural residues like wheat bran (20.6 IU/ml), rice bran (21.8 IU/ml) and sawdust (10.7 IU/ml) as carbon sources. The enzyme preparation was totally free of filter paper activity (FPase) and possessed negligible carboxymethyl cellulase (CMCase) activity; this could be an important feature of enzyme if the intended application of enzyme is in pulp and paper industries. Among nitrogen sources examined, yeast extract supported maximum xylanase production (45.74 IU/ml), and was followed by soybean meal (22.2 IU/ml) and ammonium sulphate (20 IU/ml). Maximum xylanase production was observed at initial medium pH 9 (25.6 IU/ml); however, at pH 8 and 10 also significantly high enzyme titre was observed (24 and 21.2 IU/ml, respectively). Thus, Penicillium sp. SS1 displayed capability of growing and producing xylanase at high alkaline pH (8-10). Maximum xylanase activity was reported at 50 °C, however, significantly high activity was observed at 60 °C (65.4%), however, at 70-80 °C activity was lost considerably. At 50-60 °C the enzyme retained very high activity up to 30-60 min (91-100%), however, prolonged incubation (90 min) caused considerable activity reduction (residual activity 63-68%).

IN-SYNC. III. The Dynamical State of IC 348 - A Super-virial Velocity Dispersion and a Puzzling Sign of Convergence

NASA Astrophysics Data System (ADS)

Cottaar, Michiel; Covey, Kevin R.; Foster, Jonathan B.; Meyer, Michael R.; Tan, Jonathan C.; Nidever, David L.; Chojnowski, S. Drew; da Rio, Nicola; Flaherty, Kevin M.; Frinchaboy, Peter M.; Majewski, Steve; Skrutskie, Michael F.; Wilson, John C.; Zasowski, Gail

2015-07-01

Most field stars will have encountered the highest stellar density and hence the largest number of interactions in their birth environment. Yet the stellar dynamics during this crucial phase are poorly understood. Here we analyze the radial velocities measured for 152 out of 380 observed stars in the 2-6 Myr old star cluster IC 348 as part of the SDSS-III APOGEE. The radial velocity distribution of these stars is fitted with one or two Gaussians, convolved with the measurement uncertainties including binary orbital motions. Including a second Gaussian improves the fit; the high-velocity outliers that are best fit by this second component may either (1) be contaminants from the nearby Perseus OB2 association, (2) be a halo of ejected or dispersing stars from IC 348, or (3) reflect that IC 348 has not relaxed to a Gaussian velocity distribution. We measure a velocity dispersion for IC 348 of 0.72 ± 0.07 km s-1 (or 0.64 ± 0.08 km s-1 if two Gaussians are fitted), which implies a supervirial state, unless the gas contributes more to the gravitational potential than expected. No evidence is found for a dependence of this velocity dispersion on distance from the cluster center or stellar mass. We also find that stars with lower extinction (in the front of the cloud) tend to be redshifted compared with stars with somewhat higher extinction (toward the back of the cloud). This data suggest that the stars in IC 348 are converging along the line of sight. We show that this correlation between radial velocity and extinction is unlikely to be spuriously caused by the small cluster rotation of 0.024 ± 0.013 km s-1 arcmin-1 or by correlations between the radial velocities of neighboring stars. This signature, if confirmed, will be the first detection of line of sight convergence in a star cluster. Possible scenarios for reconciling this convergence with IC 348's observed supervirial state include: (a) the cluster is fluctuating around a new virial equilibrium after a recent

Fatigue life improvements of the AISI 304 stainless steel ground surfaces by wire brushing

NASA Astrophysics Data System (ADS)

Ben Fredj, Nabil; Ben Nasr, Mohamed; Ben Rhouma, Amir; Sidhom, Habib; Braham, Chedly

2004-10-01

The surface and subsurface integrity of metallic ground components is usually characterized by an induced tensile residual stress, which has a detrimental effect on the fatigue life of these components. In particular, it tends to accelerate the initiation and growth of the fatigue cracks. In this investigation, to deliberately generate compressive residual stresses into the ground surfaces of the AISI 304 stainless steel (SS), wire brushing was applied. It was found that under the experimental conditions selected in this investigation, while the surface roughness was slightly improved by the brushing process, the surface residual stress shifted from a tensile stress (σ‖=+450 MPa) to a compressive stress (σ‖=-435 MPa). On the other hand, the work-hardened deformation layer was almost two times deeper after wire brushing. Concerning the fatigue life, an improvement of 26% in terms of endurance limit at 2×106 cycles was realized. Scanning electron microscope (SEM) observations of the fatigue fracture location and size were carried out to explain the fatigue life improvement. It was found that the enhancement of the fatigue strength could be correlated with the distribution and location of the fatigue fracture nucleation sites. Concerning the ground surfaces, it was seen that the fatigue cracks initiated at the bottom of the grinding grooves and were particularly long (150-200 µm). However, the fatigue cracks at the brushed surfaces were shorter (20-40 µm) and appeared to initiate sideways to the plowed material caused by the wire brushing. The results of the wire-brushed surface characterization have shown that significant advantages can be realized regarding surface integrity by the application of this low-cost process compared to shot peening.

Determination of Proper Austenitization Temperatures for Hot Stamping of AISI 4140 Steel

NASA Astrophysics Data System (ADS)

Samadian, Pedram; Parsa, Mohammad Habibi; Shakeri, Amid

2014-04-01

High strength steels are desirable materials for use in automobile bodies in order to reduce vehicle weight and increase the safety of car passengers, but steel grades with high strength commonly show poor formability. Recently, steels with controlled microstructures and compositions are used to gain adequate strength after hot stamping while maintaining good formability during processing. In this study, microstructure evolutions and changes in mechanical properties of AISI 4140 steel sheets resulting from the hot stamping process at different austenitization temperatures were investigated. To determine the proper austenitization temperatures, the results were compared with those of the cold-worked and cold-worked plus quench-tempered specimens. Comparisons showed that the austenitization temperatures of 1000 and 1100 °C are proper for hot stamping of 3-mm-thick AISI 4140 steel sheets due to the resultant martensitic microstructure which led to the yield and ultimate tensile strength of 1.3 and 2.1 GPa, respectively. Such conditions resulted in more favorable simultaneous strength and elongation than those of hot-stamped conventional boron steels.

French validation of the Maslach Burnout Inventory-Student Survey (MBI-SS).

PubMed

Faye-Dumanget, Christine; Carré, Julie; Le Borgne, Margaux; Boudoukha, Pr Abdel Halim

2017-12-01

Several international studies have been conducted on student burnout. To contribute to the clinical examination as well as research on the mental health of students, the MBI-SS (Maslach Burnout Inventory-Student Survey) has been validated and used in different countries but not in French. The aim of this study is to examine the validity of the 3-dimensional model of the French version of the MBI-SS, which is characterized by emotional "Emotional Exhaustion" (EE); "Cynicism" (CY); and low scores in "Academic Efficacy" (AE). A total of 667 university students were questioned to study the 3-dimensional structure of the French translation of the MBI-SS. The results validate the 3-dimensional structure of the MBI-SS and indicate satisfactory psychometric values. It is concluded that the MBI-SS can be used to assess burnout in French students. © 2017 John Wiley & Sons, Ltd.

A study on the control of melting ratio to increase mechanical properties of laser welded joints between AISI 440C and AISI 430F

NASA Astrophysics Data System (ADS)

Romoli, L.; Rashed, C. A. A.; Lovicu, G.; Ishak, R.

2015-05-01

Laser beam welding of dissimilar AISI 440C and AISI 430F stainless steels was investigated in a circular constrained configuration. The beam incidence angle and the offset of the focusing position respect to the contact point between the two materials were used as main control parameters to vary the melting ratio inside the seam. The objective of the study is twofold: to avoid surface microcracks related to the high percentage of carbon of the martensitic steel and to enhance the shear strength of the weld by making it less brittle. To reach this scope the effects of incidence angle and offset on weld bead geometry and melting ratio were studied by means of metallographic analyses, microstructure and microhardness characterization. As last step, the weld mechanical strength was tested by tensile-shear stress test on the whole seam. Experiments demonstrated that varying incidence angle and offsetting the focal position is a reliable method to modify the melting ratio and maintaining the expected resistance length at the material interface, as well. It was found that increasing the percentage of ferritic steel into the joint has beneficial effects on the weld quality and on the shear resistance. The critical carbon content determining the mechanical properties in the fusion zone can be calculated by taking into account the melting ratio.

ALMA Survey of Class II Disks in the Young Stellar Cluster IC 348

NASA Astrophysics Data System (ADS)

Ruiz, Dary; Cieza, Lucas; Williams, Jonathan; Andrews, Sean; Principe, David

2018-01-01

We present a 1.3 mm continuum survey of the young (2-3 Myr) stellar cluster IC 348 at a distance of 270 pc, which is dominated by low-mass stars. We observed 146 Class II sources (disks that are optically thick in the infrared) at 0.8 '' (200 au) resolution with a 3σ sensitivity of 0.2 MEarth. We detect 46 of the targets and construct a disk luminosity function. We compare the disk mass distribution in IC 348 to those of younger and older regions, taking into account the dependence on stellar mass. We find a clear evolution in disk masses from 1 to 5-10 Myr. The disk masses in IC 348 are significantly lower than those in Taurus (1-2 Myr) and Lupus (1-3 Myr), similar to those of Chamaleon I, (2-3 Myr) and σ-Ori (3-5 Myr) and significantly higher than in Upper Scorpius (5-10 Myr). About 20 disks in our sample (~5% of the cluster members) have estimated masses (dust + gas) of >1 MJUP. and might be the precursors of giant planets in the cluster. Some of the most massive disks include transition objects with inner opacity holes based on their infrared SEDs. From an stacking analysis of the 90 non-detections, we find that these disks have a typical dust mass of just ≤ 0.1 MEarth, even though the vast majority of their infrared SEDs remain optically thick and show little signs of evolution. Such low-mass disks are likely to be the precursors of the small rocky planets found by Kepler around M-type stars.

An investigation of the plastic fracture of AISI 4340 and 18 nickel - 200 grade maraging steels

NASA Technical Reports Server (NTRS)

Cox, T. B.; Low, J. R., Jr.

1974-01-01

The mechanisms of plastic fracture (dimpled rupture) in high-purity and commercial 18 Ni, 200 grade maraging steels and quenched and tempered AISI 4340 steels have been studied. Plastic fracture takes place in the maraging alloys through void initiation by fracture of titanium carbo-nitride inclusions and the growth of these voids until impingement results in coalescence and final fracture. The fracture of AISI 4340 steel at a yield strength of 200 ksi occurs by nucleation and subsequent growth of voids formed by fracture of the interface between manganese sulfide inclusions and the matrix. The growth of these inclusion-nucleated voids is interrupted long before coalescence by impingement, by the formation of void sheets which connect neighboring sulfide-nucleated voids.

Experimental Investigation of the Effect of Burnishing Force on Service Properties of AISI 1010 Steel Plates

NASA Astrophysics Data System (ADS)

Gharbi, F.; Sghaier, S.; Morel, F.; Benameur, T.

2015-02-01

This paper presents the results obtained with a new ball burnishing tool developed for the mechanical treatment of large flat surfaces. Several parameters can affect the mechanical behavior and fatigue of workpiece. Our study focused on the effect of the burnishing force on the surface quality and on the service properties (mechanical behavior, fatigue) of AISI 1010 steel hot-rolled plates. Experimental results assert that burnishing force not exceeding 300 N causes an increase in the ductility. In addition, results indicated that the effect of the burnishing force on the residual surface stress was greater in the direction of advance than in the cross-feed direction. Furthermore, the flat burnishing surfaces did not improve the fatigue strength of AISI 1010 steel flat specimens.

EuroPhenome and EMPReSS: online mouse phenotyping resource

PubMed Central

Mallon, Ann-Marie; Hancock, John M.

2008-01-01

EuroPhenome (http://www.europhenome.org) and EMPReSS (http://empress.har.mrc.ac.uk/) form an integrated resource to provide access to data and procedures for mouse phenotyping. EMPReSS describes 96 Standard Operating Procedures for mouse phenotyping. EuroPhenome contains data resulting from carrying out EMPReSS protocols on four inbred laboratory mouse strains. As well as web interfaces, both resources support web services to enable integration with other mouse phenotyping and functional genetics resources, and are committed to initiatives to improve integration of mouse phenotype databases. EuroPhenome will be the repository for a recently initiated effort to carry out large-scale phenotyping on a large number of knockout mouse lines (EUMODIC). PMID:17905814

EuroPhenome and EMPReSS: online mouse phenotyping resource.

PubMed

Mallon, Ann-Marie; Blake, Andrew; Hancock, John M

2008-01-01

EuroPhenome (http://www.europhenome.org) and EMPReSS (http://empress.har.mrc.ac.uk/) form an integrated resource to provide access to data and procedures for mouse phenotyping. EMPReSS describes 96 Standard Operating Procedures for mouse phenotyping. EuroPhenome contains data resulting from carrying out EMPReSS protocols on four inbred laboratory mouse strains. As well as web interfaces, both resources support web services to enable integration with other mouse phenotyping and functional genetics resources, and are committed to initiatives to improve integration of mouse phenotype databases. EuroPhenome will be the repository for a recently initiated effort to carry out large-scale phenotyping on a large number of knockout mouse lines (EUMODIC).

Isolation of a new ssDNA aptamer against staphylococcal enterotoxin B based on CNBr-activated sepharose-4B affinity chromatography.

PubMed

Hedayati Ch, Mojtaba; Amani, Jafar; Sedighian, Hamid; Amin, Mohsen; Salimian, Jafar; Halabian, Raheleh; Imani Fooladi, Abbas Ali

2016-09-01

Staphylococcus aureus are potent human pathogens possessing arsenal of virulence factors. Staphylococcal food poisoning (SFP) and respiratory infections mediated by staphylococcal enterotoxin B (SEB) are common clinical manifestations. Many diagnostic techniques are based on serological detection and quantification of SEB in different food and clinical samples. Aptamers are known as new therapeutic and detection tools which are available in different ssDNA, dsDNA and protein structures. In this study, we used a new set of ssDNA aptamers against SEB. The methods used included preparation of a dsDNA library using standard SEB protein as the target analyte, affinity chromatography matrix in microfuge tubes, SELEX procedures to isolate specific ssDNA-aptamer as an affinity ligand, aptamer purification using ethanol precipitation method, affinity binding assay using ELISA, aptamer cloning and specificity test. Among 12 readable sequences, three of them were selected as the most appropriate aptamer because of their affinity and specificity to SEB. This study presents a new set of ssDNA aptamer with favorable selectivity to SEB through 12 rounds of SELEX. Selected aptamers were used to detect SEB in infected serum samples. Results showed that SEB c1 aptamer (2 µg SEB/100 nM aptamer) had favorable specificity to SEB (kd  = 2.3 × 10(-11) ). In conclusion, aptamers can be considered as useful tools for detecting and evaluating SEB. The results showed that affinity chromatography was an affordable assay with acceptable accuracy to isolate sensitive and selective novel aptamers. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Refractory amorphous metallic (W/0.6/ Re/0.4/)76B24 coatings on steel substrates

NASA Technical Reports Server (NTRS)

Thakoor, A. P.; Lamb, J. L.; Khanna, S. K.; Mehra, M.; Johnson, W. L.

1985-01-01

Refractory metallic coatings of (W/0.6/ Re/0.4/)76B24 (WReB) have been deposited onto glass, quartz, and heat-treated AISI 52100 bearing steel substrates by dc magnetron sputtering. As-deposited WReB films are amorphous, as shown by their diffuse X-ray diffraction patterns; chemically homogeneous, according to secondary ion mass spectrometry (SIMS) analysis; and they exhibit a very high (approximately 1000 C) crystallization temperature. Adhesion strength of these coatings on heat-treated AISI 52100 steel is in excess of approximately 20,000 psi and they possess high microhardness (approximately 2400 HV50). Unlubricated wear resistance of such hard and adherent amorphous metallic coatings on AISI 52100 steel is studied using the pin-on-disc method under various loading conditions. Amorphous metallic WReB coatings, about 4 microns thick, exhibit an improvement of more than two and a half orders of magnitude in the unlubricated wear resistance over that of the uncoated AISI 52100 steel.

Structural characterization of sputter-deposited SS304+x aluminum (x = 0, 4, 7 and 10 wt.%) coatings and mechanically milled titanium, zirconium and hafnium powders

NASA Astrophysics Data System (ADS)

Seelam, Uma Maheswara Rao

Study of the metastable phases obtained by non-equilibrium processing techniques has come a long way during the past five decades. New metastable phases have often given new perspectives to the research on synthesis of novel materials systems. Metastable materials produced by two non-equilibrium processing methods were studied for this dissertation---304-type austenitic stainless steel (SS304 or Fe-18Cr-8Ni)+aluminum coatings produced by plasma enhanced magnetron sputter-deposition (PEMS) and nanocrystalline Ti, Zr and Hf powders processed by mechanical milling (MM). The objective of the study was to understand the crystallographic and microstructural aspects of these materials. Four SS304+Al coatings with a nominal Al percentages of 0, 4, 7 and 10 wt.% in the coatings were deposited on an SS304 substrate by PEMS using SS304 and Al targets. The as-deposited coatings were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and three-dimensional atom probe microscopy (3DAP). Surface morphology and chemical analysis were studied by SEM. Phase identification was carried out by XRD and TEM. The microstructural features of all the coatings, as observed in the TEM, consisted of columnar grains with the columnar grain width (a measure of grain size) increasing with an increase in the Al content. The coatings had grains with average grain sizes of about 100, 290, 320 and 980 nm, respectively for 0, 4, 7 and 10 wt.% Al. The observed grain structures and increase in grain size were related to substrate temperature during deposition. XRD results indicated that the Al-free coating consisted of the non-equilibrium ferrite and sigma phases. In the 4Al, 7Al and 10Al coatings, equilibrium ferrite and B2 phases were observed but no sigma phase was found. In 10Al coating, we were able to demonstrate experimentally using 3DAP studies that NiAl phase formation is preferred over the FeAl phase at nano scale. During

Fatigue Crack Propagation from Notched Specimens of 304 SS in elevated Temperature Aqueous Environment

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

Wire, G. L.; Mills, W. J.

2002-08-01

Fatigue crack propagation (FCP) rates for 304 stainless steel (304SS) were determined in 24 degree C and 288 degree C air and 288 degree C water using double-edged notch (DEN) specimens of 304 stainless steel (304 SS). Test performed at matched loading conditions in air and water at 288 degree C with 20-6- cc h[sub]2/kg h[sub]2O provided a direct comparison of the relative crack growth rates in air and water over a wide range of crack growth rates. The DEN crack extension ranged from short cracks (0.03-0.25 mm) to long cracks up to 4.06 mm, which are consistent with conventionalmore » deep crack tests. Crack growth rates of 304 SS in water were about 12 times the air rate. This 12X environmental enhancement persisted to crack extensions up to 4.06 mm, far outside the range associated with short crack effects. The large environmental degradation for 304 SS crack growth is consistent with the strong reduction of fatigue life in high hydrogen water. Further, very similar environmental effects w ere reported in fatigue crack growth tests in hydrogen water chemistry (HWC). Most literature data in high hydrogen water show only a mild environmental effect for 304 SS, of order 2.5 times air or less, but the tests were predominantly performed at high cyclic stress intensity or equivalently, high air rates. The environmental effect in low oxygen environments at low stress intensity depends strongly on both the stress ratio, R, and the load rise time, T[sub]r, as recently reported for austenitic stainless steel in BWR water. Fractography was performed for both tests in air and water. At 288 degree C in water, the fracture surfaces were crisply faceted with a crystallographic appearance, and showed striations under high magnification. The cleavage-like facets on the fracture surfaces suggest that hydrogen embrittlement is the primary cause of accelerated cracking.« less

The copolymer P(HEMA-co-SS) binds gluten and reduces immune response in gluten-sensitized mice and human tissues.

PubMed

Pinier, Maud; Fuhrmann, Gregor; Galipeau, Heather J; Rivard, Nathalie; Murray, Joseph A; David, Chella S; Drasarova, Hana; Tuckova, Ludmila; Leroux, Jean-Christophe; Verdu, Elena F

2012-02-01

Copolymers of hydroxyethyl methacrylate and styrene sulfonate complex with isolated gliadin (the toxic fraction of gluten) and prevent damage to the intestinal barrier in HLA-HCD4/DQ8 mice. We studied the activity toward gluten and hordein digestion and biologic effects of poly(hydroxyethyl methacrylate-co-styrene sulfonate (P(HEMA-co-SS)). We also investigated the effect of gliadin complex formation in intestinal biopsy specimens from patients with celiac disease. We studied the ability of P(HEMA-co-SS) to reduce digestion of wheat gluten and barley hordein into immunotoxic peptides using liquid chromatography-mass spectrometry. The biodistribution and pharmacokinetic profile of orally administered P(HEMA-co-SS) was established in rodents using tritium-labeled polymer. We assessed the capacity of P(HEMA-co-SS) to prevent the immunologic and intestinal effects induced by a gluten-food mixture in gluten-sensitized HLA-HCD4/DQ8 mice after short-term and long-term administration. We measured the effects of gliadin complex formation on cytokine release ex vivo using intestinal biopsy specimens from patients with celiac disease. P(HEMA-co-SS) reduced digestion of wheat gluten and barley hordein in vitro, thereby decreasing formation of toxic peptides associated with celiac disease. After oral administration to rodents, P(HEMA-co-SS) was predominantly excreted in feces, even in the presence of low-grade mucosal inflammation and increased intestinal permeability. In gluten-sensitized mice, P(HEMA-co-SS) reduced paracellular permeability, normalized anti-gliadin immunoglobulin A in intestinal washes, and modulated the systemic immune response to gluten in a food mixture. Furthermore, incubation of P(HEMA-co-SS) with mucosal biopsy specimens from patients with celiac disease showed that secretion of tumor necrosis factor-α was reduced in the presence of partially digested gliadin. The copolymer P(HEMA-co-SS) reduced digestion of wheat gluten and barley hordein and

Kidney Disease among Patients with Sickle Cell Disease, Hemoglobin SS and SC

PubMed Central

Drawz, Paul; Ayyappan, Sabarish; Nouraie, Mehdi; Saraf, Santosh; Gordeuk, Victor; Hostetter, Thomas; Gladwin, Mark T.

2016-01-01

Background and objectives Sickle cell disease (SCD) is an inherited anemia that afflicts millions worldwide. Kidney disease is a major contributor to its morbidity and mortality. We examined contemporary and historical SCD populations to understand how renal disease behaved in hemoglobin SS (HbSS) compared with HbSC. Design, setting, participants, & measurements Kidney function was examined in the multicentered Treatment of Pulmonary Hypertension and Sickle Cell Disease with Sildenafil Therapy (Walk-PHaSST) Trial (HbSS=463; HbSC=127; years 2007–2009) and historical comparator populations from the Cooperative Study of Sickle Cell Disease (CSSCD; HbSS=708) and the Multicenter Study of Hydroxyurea in Sickle Cell Disease (MSH; HbSS=299). Results In adults with SCD, eGFR was lower among older individuals: −1.78 ml/min per 1.73 m2 per year of age (95% confidence interval [95% CI], −2.06 to −1.50; Walk-PHaSST Trial), −1.75 ml/min per 1.73 m2 per year of age (95% CI, −2.05 to −1.44; MSH), and −1.69 ml/min per 1.73 m2 per year of age (95% CI, −2.00 to −1.38; CSSCD) in HbSS compared with −1.09 ml/min per 1.73 m2 per year of age (95% CI, −1.39 to −0.75) in HbSC (Walk-PHaSST Trial). Macroalbuminuria was seen in 20% of participants with SCD (HbSS or HbSC; P=0.45; Walk-PHaSST Trial), but microalbuminuria was more prevalent in HbSS (44% versus 23% in HbSC; P<0.002). In the Walk-PHaSST Trial, albuminuria was associated with hemolysis (higher lactate dehydrogenase, P<0.001; higher absolute reticulocyte count, P<0.02; and lower Hb, P=0.07) and elevated systolic BP (P<0.001) in HbSS. One half of all participants with HbSS (20 of 39) versus one fifth without (41 of 228) elevated tricuspid regurgitant jet velocity (≥3 m/s; adverse prognostic indicator in SCD) had macroalbuminuria (P<0.001). In the CSSCD, overt proteinuria, detected (less sensitively) by urine dipstick, associated with higher 3-year mortality (odds ratio, 2.48; 95% CI, 1.07 to 5.77). Serum

Electrochemical and pitting corrosion resistance of AISI 4145 steel subjected to massive laser shock peening treatment with different coverage layers

NASA Astrophysics Data System (ADS)

Lu, J. Z.; Han, B.; Cui, C. Y.; Li, C. J.; Luo, K. Y.

2017-02-01

The effects of massive laser shock peening (LSP) treatment with different coverage layers on residual stress, pitting morphologies in a standard corrosive solution and electrochemical corrosion resistance of AISI 4145 steel were investigated by pitting corrosion test, potentiodynamic polarisation test, and SEM observations. Results showed massive LSP treatment can effectively cause an obvious improvement of pitting corrosion resistance of AISI 4145 steel, and increased coverage layer can also gradually improve its corrosion resistance. Massive LSP treatment with multiple layers was shown to influence pitting corrosion behaviour in a standard corrosive solution.

Microstructure, Mechanical and Corrosion Properties of Friction Stir-Processed AISI D2 Tool Steel

NASA Astrophysics Data System (ADS)

Yasavol, Noushin; Jafari, Hassan

2015-05-01

In this study, AISI D2 tool steel underwent friction stir processing (FSP). The microstructure, mechanical properties, and corrosion resistance of the FSPed materials were then evaluated. A flat WC-Co tool was used; the rotation rate of the tool varied from 400 to 800 rpm, and the travel speed was maintained constant at 385 mm/s during the process. FSP improved mechanical properties and produced ultrafine-grained surface layers in the tool steel. Mechanical properties improvement is attributed to the homogenous distribution of two types of fine (0.2-0.3 μm) and coarse (1.6 μm) carbides in duplex ferrite-martensite matrix. In addition to the refinement of the carbides, the homogenous dispersion of the particles was found to be more effective in enhancing mechanical properties at 500 rpm tool rotation rate. The improved corrosion resistance was observed and is attributed to the volume fraction of low-angle grain boundaries produced after friction stir process of the AISI D2 steel.

[The province of East Prussia and "euthanasia" during national socialism: the SS-"Aktion Lange" and "Aktion T4"].

PubMed

Topp, Sascha; Fuchs, Petra; Hohendorf, Gerrit; Richter, Paul; Rotzoll, Maike

2008-01-01

During World War II, psychiatric patients hospitalized in asylums in Eastern Prussia became victims of two separate killing programmes: first, by the SS-special command Lange, second by the centrally (in Berlin) organized "euthanasia"-"Aktion T4". By an analysis of the patient files of the victims, the present paper shows that the historical actors responsible for the killings were communicating with each other. It is now also possible to reconstruct the exact dynamic in time and space of the killings. A comparative analysis of the selection criteria within the total population of the asylums documents that in both programs, the responsible historical actors included physicians and provincial administrative personnel; it further shows that under the conditions of war, only patients who were able to contribute to the asylum work and economy, and were behaviourally adapted could survive.

Validation of Robotic Surgery Simulator (RoSS).

PubMed

Kesavadas, Thenkurussi; Stegemann, Andrew; Sathyaseelan, Gughan; Chowriappa, Ashirwad; Srimathveeravalli, Govindarajan; Seixas-Mikelus, Stéfanie; Chandrasekhar, Rameella; Wilding, Gregory; Guru, Khurshid

2011-01-01

Recent growth of daVinci Robotic Surgical System as a minimally invasive surgery tool has led to a call for better training of future surgeons. In this paper, a new virtual reality simulator, called RoSS is presented. Initial results from two studies - face and content validity, are very encouraging. 90% of the cohort of expert robotic surgeons felt that the simulator was excellent or somewhat close to the touch and feel of the daVinci console. Content validity of the simulator received 90% approval in some cases. These studies demonstrate that RoSS has the potential of becoming an important training tool for the daVinci surgical robot.

ssDNA damage dependence from singlet oxygen concentration at photodynamic interaction

NASA Astrophysics Data System (ADS)

Klimenko, V. V.; Kaydanov, N. E.; Emelyanov, A. K.; Bogdanov, A. A.

2017-11-01

Single stranded DNA damage at photodynamic treatment with Radachlorin photosensitizer was investigated. Chemical trap method was used to evaluate generation of singlet oxygen in water solution. Interaction of singlet oxygen with ssDNA resulted into decrease of the replication activity of ssDNA. DNA stopped replicating during PCR at irradiation doses greater than 15 J/cm2 and concentration of photosensitizer [PS] = 3.8 μM. The dependence of replication activity of ssDNA on generated singlet oxygen concentration was identified.

Serrated Flow Behavior of Aisi 316l Austenitic Stainless Steel for Nuclear Reactors

NASA Astrophysics Data System (ADS)

Li, Qingshan; Shen, Yinzhong; Han, Pengcheng

2017-10-01

AISI 316L austenitic stainless steel is a candidate material for Generation IV reactors. In order to investigate the influence of temperature on serrated flow behavior, tensile tests were performed at temperatures ranging from 300 to 700 °C at an initial strain rate of 2×10-4 s-1. Another group of tensile tests were carried out at strain rates ranging from 1×10-4 to 1×10-2 s-1 at 600 °C to examine the influence of strain rates on serrated flow behavior. The steel exhibited serrated flow, suggesting the occurrence of dynamic strain ageing at 450-650°C. No plateau of yield stresses of the steel was observed at an initial strain rate of 2×10-4 s-1. The effective activation energy for serrated flow occurrence was calculated to be about 254.72 kJ/mol-1. Cr, Mn, Ni and Mo solute atoms are expected to be responsible for dynamic strain ageing at high temperatures of 450-650 °C in the steel.

A study of cumulative fatigue damage in AISI 4130 steel

NASA Technical Reports Server (NTRS)

Jeelani, S.; Musial, M.

1986-01-01

Experimental data were obtained using AISI 4130 steel under stress ratios of -1 and 0. A study of cumulative fatigue damage using Miner's and Kramer's equations for stress ratios of -1 and 0 for low-high, low-high-mixed, high-low, and high-low-mixed stress sequences has revealed that there is a close agreement between the theoretical and experimental values of fatigue damage and fatigue life. Kramer's equation predicts less conservative and more realistic cumulative fatigue damage than the popularly used Miner's rule does.

On femtosecond laser shock peening of stainless steel AISI 316

NASA Astrophysics Data System (ADS)

Hoppius, Jan S.; Kukreja, Lalit M.; Knyazeva, Marina; Pöhl, Fabian; Walther, Frank; Ostendorf, Andreas; Gurevich, Evgeny L.

2018-03-01

In this paper we report on the competition in metal surface hardening between the femtosecond shock peening on the one hand, and formation of laser-induced periodic surface structures (LIPSS) and surface oxidation on the other hand. Peening of the stainless steel AISI 316 due to shock loading induced by femtosecond laser ablation was successfully demonstrated. However, for some range of processing parameters, surface erosion due to LIPSS and oxidation seems to dominate over the peening effect. Strategies to increase the peening efficiency are discussed.

Analysis of the Enameled AISI 316LVM Stainless Steel

NASA Astrophysics Data System (ADS)

Bukovec, Mitja; Xhanari, Klodian; Lešer, Tadej; Petovar, Barbara; Finšgar, Matjaž

2018-03-01

In this work, four different enamels were coated on AISI 316LVM stainless steel and the corrosion resistance of these samples was tested in 5 wt.% NaCl solution at room temperature. The preparation procedure of the enamels was optimized in terms of firing temperature, time and composition. First the thermal expansion was measured using dilatometry followed by electrochemical analysis using chronopotentiometry, electrochemical impedance spectroscopy and cyclic polarization. The topography of the most resistant sample was obtained by 3D-profilometry. All samples coated with enamel showed significantly higher corrosion and dilatation resistance compared with the uncoated stainless steel material.

Investigating Tribological Characteristics of HVOF Sprayed AISI 316 Stainless Steel Coating by Pulsed Plasma Nitriding

NASA Astrophysics Data System (ADS)

Mindivan, H.

2018-01-01

In this study, surface modification of aluminum alloy using High-Velocity Oxygen Fuel (HVOF) thermal spray and pulsed plasma nitriding processes was investigated. AISI 316 stainless steel coating on 1050 aluminum alloy substrate by HVOF process was pulsed plasma nitrided at 793 K under 0.00025 MPa pressure for 43200 s in a gas mixture of 75 % N2 and 25 % H2. The results showed that the pulse plasma nitriding process produced a surface layer with CrN, iron nitrides (Fe3N, Fe4N) and expanded austenite (γN). The pulsed plasma nitrided HVOF-sprayed coating showed higher surface hardness, lower wear rate and coefficient of friction than the untreated HVOF-sprayed one.

Enhancing the Hardness of Sintered SS 17-4PH Using Nitriding Process for Bracket Orthodontic Application

NASA Astrophysics Data System (ADS)

Suharno, B.; Supriadi, S.; Ayuningtyas, S. T.; Widjaya, T.; Baek, E. R.

2018-01-01

Brackets orthodontic create teeth movement by applying force from wire to bracket then transferred to teeth. However, emergence of friction between brackets and wires reduces load for teeth movement towards desired area. In order to overcome these problem, surface treatment like nitriding chosen as a process which could escalate efficiency of transferred force by improving material hardness since hard materials have low friction levels. This work investigated nitriding treatment to form nitride layer which affecting hardness of sintered SS 17-4PH. The nitride layers produced after nitriding process at various temperature i.e. 470°C, 500°C, 530°C with 8hr holding time under 50% NH3 atmosphere. Optical metallography was conducted to compare microstructure of base and surface metal while the increasing of surface hardness then observed using vickers microhardness tester. Hardened surface layer was obtained after gaseous nitriding process because of nitride layer that contains Fe4N, CrN and Fe-αN formed. Hardness layers can achieved value 1051 HV associated with varies thickness from 53 to 119 μm. The presence of a precipitation process occurring in conjunction with nitriding process can lead to a decrease in hardness due to nitrogen content diminishing in solid solution phase. This problem causes weakening of nitrogen expansion in martensite lattice.

Architecture and ssDNA interaction of the Timeless-Tipin-RPA complex

PubMed Central

Witosch, Justine; Wolf, Eva; Mizuno, Naoko

2014-01-01

The Timeless-Tipin (Tim-Tipin) complex, also referred to as the fork protection complex, is involved in coordination of DNA replication. Tim-Tipin is suggested to be recruited to replication forks via Replication Protein A (RPA) but details of the interaction are unknown. Here, using cryo-EM and biochemical methods, we characterized complex formation of Tim-Tipin, RPA and single-stranded DNA (ssDNA). Tim-Tipin and RPA form a 258 kDa complex with a 1:1:1 stoichiometry. The cryo-EM 3D reconstruction revealed a globular architecture of the Tim-Tipin-RPA complex with a ring-like and a U-shaped domain covered by a RPA lid. Interestingly, RPA in the complex adopts a horse shoe-like shape resembling its conformation in the presence of long ssDNA (>30 nucleotides). Furthermore, the recruitment of the Tim-Tipin-RPA complex to ssDNA is modulated by the RPA conformation and requires RPA to be in the more compact 30 nt ssDNA binding mode. The dynamic formation and disruption of the Tim-Tipin-RPA-ssDNA complex implicates the RPA-based recruitment of Tim-Tipin to the replication fork. PMID:25348395

LOFAR 150-MHz observations of SS 433 and W 50

NASA Astrophysics Data System (ADS)

Broderick, J. W.; Fender, R. P.; Miller-Jones, J. C. A.; Trushkin, S. A.; Stewart, A. J.; Anderson, G. E.; Staley, T. D.; Blundell, K. M.; Pietka, M.; Markoff, S.; Rowlinson, A.; Swinbank, J. D.; van der Horst, A. J.; Bell, M. E.; Breton, R. P.; Carbone, D.; Corbel, S.; Eislöffel, J.; Falcke, H.; Grießmeier, J.-M.; Hessels, J. W. T.; Kondratiev, V. I.; Law, C. J.; Molenaar, G. J.; Serylak, M.; Stappers, B. W.; van Leeuwen, J.; Wijers, R. A. M. J.; Wijnands, R.; Wise, M. W.; Zarka, P.

2018-04-01

We present Low-Frequency Array (LOFAR) high-band data over the frequency range 115-189 MHz for the X-ray binary SS 433, obtained in an observing campaign from 2013 February to 2014 May. Our results include a deep, wide-field map, allowing a detailed view of the surrounding supernova remnant W 50 at low radio frequencies, as well as a light curve for SS 433 determined from shorter monitoring runs. The complex morphology of W 50 is in excellent agreement with previously published higher frequency maps; we find additional evidence for a spectral turnover in the eastern wing, potentially due to foreground free-free absorption. Furthermore, SS 433 is tentatively variable at 150 MHz, with both a debiased modulation index of 11 per cent and a χ2 probability of a flat light curve of 8.2 × 10-3. By comparing the LOFAR flux densities with contemporaneous observations carried out at 4800 MHz with the RATAN-600 telescope, we suggest that an observed ˜0.5-1 Jy rise in the 150-MHz flux density may correspond to sustained flaring activity over a period of approximately 6 months at 4800 MHz. However, the increase is too large to be explained with a standard synchrotron bubble model. We also detect a wealth of structure along the nearby Galactic plane, including the most complete detection to date of the radio shell of the candidate supernova remnant G 38.7-1.4. This further demonstrates the potential of supernova remnant studies with the current generation of low-frequency radio telescopes.

[Study and development of a new automatic suction system (SS) of intratracheal sputum in order to improve QOL of many patients with tracheostomy mechanical ventilation (TMV) and their family members by this new autonomic SS].

PubMed

Hokezu, Youichi; Yamamoto, Makoto; Tokunaga, Syuichi; Niikura, Makoto; Nagamatsu, Keiji; Kira, Jun-ichi; Fukunaga, Toshihide; Shima, Kouji; Kikuchi, Seiji; Kimura, Itaru; Kondo, Kiyohiko; Mori, Teruhiko; Goto, Katumasa; Takigami, Shigeru; Shioya, Keiichi; Uehara, Minako

2009-11-01

In Japan, many patients equipped with TMV are under medical treatment at home after 1990. These patients can't put out sputa in trachea, so that these patient's family members must suck these patient's intratracheal sputa all days. Mr Yamamoto and Mr Tokunaga, main researchers of this study, began the study on the automatic SS of itratracheal sputa from 1999. In first stage, They developed the intermittent SS in detaining the suction tube within tracheal cannula, monitering the intratracheal pressure, but this system takes the ventilation away from the patient. Hypoventilation caused by this SS may cause the serious accident in patient. Therefore, we remodel the SS from intermittent SS to rollerpomp-type SS continuing to suck the itratracheal sputa with low volume from 2004, and thereafter we made up the SS of piston pomp type-SS finally at 2007. We developed the tracheal cannula with double suction holes of inner and lower hole in the lower part of its cannula together with the suction machine. We think that the practical use of this automatic SS will bring these patients with TMV and their family members great benefits. We desire that the practical use of this SS will be realized as soon as possible.

Alterations in hypothalamic KiSS-1 system in experimental diabetes: early changes and functional consequences.

PubMed

Castellano, J M; Navarro, V M; Roa, J; Pineda, R; Sánchez-Garrido, M A; García-Galiano, D; Vigo, E; Dieguez, C; Aguilar, E; Pinilla, L; Tena-Sempere, M

2009-02-01

Using long-term streptozotocin (STZ)-treated male rats, we recently proposed that defective function of hypothalamic KiSS-1 system is mechanistically relevant for central hypogonadotropism of uncontrolled diabetes. However, the temporal pattern of such defects and its potential contribution to disturbed gonadotropin secretion in the diabetic female remain so far unexplored. To cover these issues, expression analyses and hormonal tests were conducted in diabetic male (1 wk after STZ; short term) and female (4 wk after STZ; long term) rats. Short-term diabetic males had lower basal testosterone levels and decreased gonadotropin responses to orchidectomy (ORX), which associated with significantly attenuated post-ORX rises of hypothalamic KiSS-1 mRNA. Yet kisspeptin administration to diabetic males was able to acutely elicit supramaximal LH and testosterone responses and normalize post-ORX gonadotropin secretion. Long-term diabetic females showed persistent anestrus and significantly decreased basal gonadotropin levels as well as blunted LH responses to ovariectomy; changes that were linked to lowering of basal and postovariectomy expression of hypothalamic KiSS-1 mRNA. Moreover, despite prevailing gonadotropin suppression, LH responses to acute kisspeptin administration were fully preserved, and even enhanced after its repeated injection, in diabetic females. In sum, our present findings further define the temporal course and mechanistic relevance of altered hypothalamic KiSS-1 system in the hypogonadotropic state of uncontrolled diabetes. Furthermore, our data provide the basis for the potential therapeutic intervention of the KiSS-1 system as adjuvant in the management of disturbed gonadotropin secretion of type 1 diabetes in the female.

Study of advanced communications satellite systems based on SS-FDMA

NASA Technical Reports Server (NTRS)

Kiesling, J.

1980-01-01

A satellite communication system based on the use of a multiple, contiguous beam satellite antenna and frequency division multiple access (FDMA) is studied. Emphasis is on the evaluation of the feasibility of SS (satellite switching) FDMA technology, particularly the multiple, contiguous beam antenna, the onboard switch and channelization, and on methods to overcome the effects of severe Ka band fading caused by precipitation. This technology is evaluated and plans for technology development and evaluation are given. The application of SS-FDMA to domestic satellite communications is also evaluated. Due to the potentially low cost Earth stations, SS-FDMA is particularly attractive for thin route applications up to several hundred kilobits per second, and offers the potential for competing with terrestrial facilities at low data rates and over short routes. The onboard switch also provides added route flexibility for heavy route systems. The key beneficial SS-FDMA strategy is to simplify and thus reduce the cost of the direct access Earth station at the expense of increased satellite complexity.

MUFOLD-SS: New deep inception-inside-inception networks for protein secondary structure prediction.

PubMed

Fang, Chao; Shang, Yi; Xu, Dong

2018-05-01

Protein secondary structure prediction can provide important information for protein 3D structure prediction and protein functions. Deep learning offers a new opportunity to significantly improve prediction accuracy. In this article, a new deep neural network architecture, named the Deep inception-inside-inception (Deep3I) network, is proposed for protein secondary structure prediction and implemented as a software tool MUFOLD-SS. The input to MUFOLD-SS is a carefully designed feature matrix corresponding to the primary amino acid sequence of a protein, which consists of a rich set of information derived from individual amino acid, as well as the context of the protein sequence. Specifically, the feature matrix is a composition of physio-chemical properties of amino acids, PSI-BLAST profile, and HHBlits profile. MUFOLD-SS is composed of a sequence of nested inception modules and maps the input matrix to either eight states or three states of secondary structures. The architecture of MUFOLD-SS enables effective processing of local and global interactions between amino acids in making accurate prediction. In extensive experiments on multiple datasets, MUFOLD-SS outperformed the best existing methods and other deep neural networks significantly. MUFold-SS can be downloaded from http://dslsrv8.cs.missouri.edu/~cf797/MUFoldSS/download.html. © 2018 Wiley Periodicals, Inc.

Taguchi Optimization of Cutting Parameters in Turning AISI 1020 MS with M2 HSS Tool

NASA Astrophysics Data System (ADS)

Sonowal, Dharindom; Sarma, Dhrupad; Bakul Barua, Parimal; Nath, Thuleswar

2017-08-01

In this paper the effect of three cutting parameters viz. Spindle speed, Feed and Depth of Cut on surface roughness of AISI 1020 mild steel bar in turning was investigated and optimized to obtain minimum surface roughness. All the experiments are conducted on HMT LB25 lathe machine using M2 HSS cutting tool. Ranges of parameters of interest have been decided through some preliminary experimentation (One Factor At a Time experiments). Finally a combined experiment has been carried out using Taguchi’s L27 Orthogonal Array (OA) to study the main effect and interaction effect of the all three parameters. The experimental results were analyzed with raw data ANOVA (Analysis of Variance) and S/N data (Signal to Noise ratio) ANOVA. Results show that Spindle speed, Feed and Depth of Cut have significant effects on both mean and variation of surface roughness in turning AISI 1020 mild steel. Mild two factors interactions are observed among the aforesaid factors with significant effects only on the mean of the output variable. From the Taguchi parameter optimization the optimum factor combination is found to be 630 rpm spindle speed, 0.05 mm/rev feed and 1.25 mm depth of cut with estimated surface roughness 2.358 ± 0.970 µm. A confirmatory experiment was conducted with the optimum factor combination to verify the results. In the confirmatory experiment the average value of surface roughness is found to be 2.408 µm which is well within the range (0.418 µm to 4.299 µm) predicted for confirmatory experiment.

Laser-Arc Hybrid Welding of Dissimilar Titanium Alloy and Stainless Steel Using Copper Wire

NASA Astrophysics Data System (ADS)

Gao, Ming; Chen, Cong; Wang, Lei; Wang, Zemin; Zeng, Xiaoyan

2015-05-01

Laser-arc hybrid welding with Cu3Si filler wire was employed to join dissimilar Ti6Al4V titanium alloy and AISI316 stainless steel (316SS). The effects of welding parameters on bead shape, microstructure, mechanical properties, and fracture behavior were investigated in detail. The results show that cross-weld tensile strength of the joints is up to 212 MPa. In the joint, obvious nonuniformity of the microstructure is found in the fusion zone (FZ) and at the interfaces from the top to the bottom, which could be improved by increasing heat input. For the homogeneous joint, the FZ is characterized by Fe67- x Si x Ti33 dendrites spreading on α-Cu matrix, and the two interfaces of 316SS/FZ and FZ/Ti6Al4V are characterized by a bamboo-like 316SS layer and a CuTi2 layer, respectively. All the tensile samples fractured in the hardest CuTi2 layer at Ti6Al4V side of the joints. The fracture surface is characterized by river pattern revealing brittle cleavage fracture. The bead formation mechanisms were discussed according to the melt flow and the thermodynamic calculation.

Damage Analysis of Tensile Deformation of Co-rolled SMATed 304SS

NASA Astrophysics Data System (ADS)

Guo, X.; Leung, A. Y. T.; Chen, A.; Ruan, H.; Lu, J.

2010-05-01

One of recent experimental progresses in strengthening and toughening metals simultaneously is to adopt techniques of surface mechanical attrition treatment (SMAT) and warm co-rolling to 304 stainless steel (SS). To capture deformation behavior and associated damage initiation/evolution process in the co-rolled SMATed 304SS, cohesive finite element method (CFEM) is employed in this paper and simulation results are in agreement with experimental results. Both strengthening effect due to high yield stress of the nanograin layer and toughening effect due to non-localized damage in the nanograin layer are captured. Effect of energy release rate of nanograin layer on failure strain of layered co-rolled SMATed 304SS is investigated. It is found that the more brittle the nanograin layer is, the more potential necking sites in the nanograin layer are, and the more ductile the layered co-rolled SMATed 304SS is.

Administration of antioxidant peptide SS-31 attenuates transverse aortic constriction-induced pulmonary arterial hypertension in mice.

PubMed

Lu, Hung-I; Huang, Tien-Hung; Sung, Pei-Hsun; Chen, Yung-Lung; Chua, Sarah; Chai, Han-Yan; Chung, Sheng-Ying; Liu, Chu-Feng; Sun, Cheuk-Kwan; Chang, Hsueh-Wen; Zhen, Yen-Yi; Lee, Fan-Yen; Yip, Hon-Kan

2016-05-01

Antioxidant peptide SS-31 is a class of cell-permeable small peptides, which selectively resides on the inner mitochondrial membrane and possesses intrinsic mitochondrial protective capacities. In this study we investigated the therapeutic effects of antioxidant peptide SS-31 on transverse aortic constriction (TAC)-induced pulmonary arterial hypertension (PAH) in a murine model. Adult male mice were divided into 3 groups: sham-operated mice, TAC mice, and TAC+SS-31 mice that underwent TAC surgery and received SS-31 (2 mg/d, ip) for 60 d. The right ventricular systolic blood pressure (RVSBP) was measured on d 60 prior to sacrificing the mice; then their right heart and lung tissues were collected for histological and biochemical examinations. Lung injury scores were defined by the increased crowded area and decreased number of alveolar sacs. TAC mice showed significantly higher RVSBP compared with sham-operated mice, the elevation was substantially suppressed in TAC+SS-31 mice. The same pattern of changes was found in pulmonary levels of oxidative stress proteins (NOX-1/NOX-2/oxidized proteins), cytosolic cytochrome c, biomarkers related to inflammation (MMP-9/TNF-α/iNOS), calcium overload index (TRPC1, 2, 4, 6), apoptosis (mitochondrial BAX, cleaved caspase 3/PARP), fibrosis (Smad3/TGF-β), hypoxic (HIF-1α), DNA damage (γ-H2AX) and endothelial function (eNOS/ET-1R), as well as in lung injury score, number of muscularized vessels in lungs, number of TRPC1(+) and HIF-1α(+) cells in pulmonary artery, and number of γ-H2AX(+) and Ki-67(+) cells in lung parenchyma. An opposite pattern of changes was observed in pulmonary anti-fibrotic markers (Smad1/5, BMP-2), number of small vessels, and number of alveolar sacs. In contrast, the levels of antioxidant proteins (HO-1/NQO-1/GR/GPx) in lung parenchyma were progressively and significantly increased from sham-operated mice, TAC mice to TAC+SS-31 mice. Antioxidant peptide SS-31 administration effectively attenuates TAC

Inhalation toxicity of 316L stainless steel powder in relation to bioaccessibility.

PubMed

Stockmann-Juvala, H; Hedberg, Y; Dhinsa, N K; Griffiths, D R; Brooks, P N; Zitting, A; Wallinder, I Odnevall; Santonen, T

2013-11-01

The Globally Harmonized System for Classification and Labelling of Chemicals (GHS) considers metallic alloys, such as nickel (Ni)-containing stainless steel (SS), as mixtures of substances, without considering that alloys behave differently compared to their constituent metals. This study presents an approach using metal release, explained by surface compositional data, for the prediction of inhalation toxicity of SS AISI 316L. The release of Ni into synthetic biological fluids is >1000-fold lower from the SS powder than from Ni metal, due to the chromium(III)-rich surface oxide of SS. Thus, it was hypothesized that the inhalation toxicity of SS is significantly lower than what could be predicted based on Ni metal content. A 28-day inhalation study with rats exposed to SS 316L powder (<4 µm, mass median aerodynamic diameter 2.5-3.0 µm) at concentrations up to 1.0 mg/L showed accumulation of metal particles in the lung lobes, but no signs of inflammation, although Ni metal caused lung toxicity in a similar published study at significantly lower concentrations. It was concluded that the bioaccessible (released) fraction, rather than the elemental nominal composition, predicts the toxicity of SS powder. The study provides a basis for an approach for future validation, standardization and risk assessment of metal alloys.

Architecture and ssDNA interaction of the Timeless-Tipin-RPA complex.

PubMed

Witosch, Justine; Wolf, Eva; Mizuno, Naoko

2014-11-10

The Timeless-Tipin (Tim-Tipin) complex, also referred to as the fork protection complex, is involved in coordination of DNA replication. Tim-Tipin is suggested to be recruited to replication forks via Replication Protein A (RPA) but details of the interaction are unknown. Here, using cryo-EM and biochemical methods, we characterized complex formation of Tim-Tipin, RPA and single-stranded DNA (ssDNA). Tim-Tipin and RPA form a 258 kDa complex with a 1:1:1 stoichiometry. The cryo-EM 3D reconstruction revealed a globular architecture of the Tim-Tipin-RPA complex with a ring-like and a U-shaped domain covered by a RPA lid. Interestingly, RPA in the complex adopts a horse shoe-like shape resembling its conformation in the presence of long ssDNA (>30 nucleotides). Furthermore, the recruitment of the Tim-Tipin-RPA complex to ssDNA is modulated by the RPA conformation and requires RPA to be in the more compact 30 nt ssDNA binding mode. The dynamic formation and disruption of the Tim-Tipin-RPA-ssDNA complex implicates the RPA-based recruitment of Tim-Tipin to the replication fork. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Effect of Brass Interlayer Sheet on Microstructure and Joint Performance of Ultrasonic Spot-Welded Copper-Steel Joints

NASA Astrophysics Data System (ADS)

Satpathy, Mantra Prasad; Kumar, Abhishek; Sahoo, Susanta Kumar

2017-07-01

Solid-state ultrasonic spot welding (USW) inevitably offers a potential solution for joining dissimilar metal combination like copper (Cu) and steel (SS). In this study, the USW has been performed on Cu (UNS C10100) and SS (AISI 304) with brass interlayer by varying various welding parameters, aiming to identify the interfacial reaction, changes in microstructure and weld strength. The highest tensile shear and T-peel failure loads of 1277 and 174 N are achieved at the optimum conditions like 68 µm of vibration amplitude, 0.42 MPa of weld pressure and 1 s of weld time. The fractured surface analysis of brass interlayer and AISI 304 stainless steel samples reveals the features like swirls, voids and intermetallic compounds (IMCs). These IMCs are composed of CuZn and FeZn composite-like structures with 1.0 μm thickness. This confirms that the weld quality is specifically sensitive to the levels of input parameter combinations as well as the type of material present on the sonotrode side.

RPA homologs and ssDNA processing during meiotic recombination.

PubMed

Ribeiro, Jonathan; Abby, Emilie; Livera, Gabriel; Martini, Emmanuelle

2016-06-01

Meiotic homologous recombination is a specialized process that involves homologous chromosome pairing and strand exchange to guarantee proper chromosome segregation and genetic diversity. The formation and repair of DNA double-strand breaks (DSBs) during meiotic recombination differs from those during mitotic recombination in that the homologous chromosome rather than the sister chromatid is the preferred repair template. The processing of single-stranded DNA (ssDNA) formed on intermediate recombination structures is central to driving the specific outcomes of DSB repair during meiosis. Replication protein A (RPA) is the main ssDNA-binding protein complex involved in DNA metabolism. However, the existence of RPA orthologs in plants and the recent discovery of meiosis specific with OB domains (MEIOB), a widely conserved meiosis-specific RPA1 paralog, strongly suggest that multiple RPA complexes evolved and specialized to subdivide their roles during DNA metabolism. Here we review ssDNA formation and maturation during mitotic and meiotic recombination underlying the meiotic specific features. We describe and discuss the existence and properties of MEIOB and multiple RPA subunits in plants and highlight how they can provide meiosis-specific fates to ssDNA processing during homologous recombination. Understanding the functions of these RPA homologs and how they interact with the canonical RPA subunits is of major interest in the fields of meiosis and DNA repair.

Very high resolution observations of SS433 at 10.65 GHz

NASA Technical Reports Server (NTRS)

Geldzahler, B. J.; Downes, A. J. B.; Shaffer, D. B.

1981-01-01

Observations of SS433 made on June 12, 1979, from West Germany, Massachusetts, and West Virginia are discussed. It is noted that SS433 did not show fringes on any baseline although all the calibration sources were seen at their expected strengths. The measured total flux density of SS433 was found to be approximately 0.5 Jy, consistent with previous observations. The source was observed by on-offs at each telescope, which indicates that they were all pointed properly during the observations. The absence of fringes is not attributed to poor observing conditions or instrumental difficulties. It is concluded that if all the 10.65 GHz radiation emanates from a single component, then that component is at least 0.005 arcsec (approximately 10 to the 14th cm) in size. The measurements made on more sensitive intercontinental baselines indicate that there is no component of SS433 smaller than 0.001 arcsec emitting 10.65 GHz radiation above a level of 50 mJy.

An improved DNA force field for ssDNA interactions with gold nanoparticles

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

Jiang, Xiankai; Huai, Ping; Fan, Chunhai

The widespread applications of single-stranded DNA (ssDNA) conjugated gold nanoparticles (AuNPs) have spurred an increasing interest in the interactions between ssDNA and AuNPs. Despite extensive studies using the most sophisticated experimental techniques, the detailed molecular mechanisms still remain largely unknown. Large scale molecular dynamics (MD) simulations can thus be used to supplement experiments by providing complementary information about ssDNA-AuNP interactions. However, up to now, all modern force fields for DNA were developed based on the properties of double-stranded DNA (dsDNA) molecules, which have hydrophilic outer backbones “protecting” hydrophobic inner nucleobases from water. Without the double-helix structure of dsDNA and thusmore » the “protection” by the outer backbone, the nucleobases of ssDNA are directly exposed to solvent, and their behavior in water is very different from that of dsDNA, especially at the interface with nanoparticles. In this work, we have improved the force field of ssDNA for use with nanoparticles, such as AuNPs, based on recent experimental results and quantum mechanics calculations. With the new improved force field, we demonstrated that a poly(A) sequence adsorbed on a AuNP surface is much more stable than a poly(T) sequence, which is consistent with recent experimental observations. On the contrary, the current standard force fields, including AMBER03, CHARMM27, and OPLSAA, all gave erroneous results as compared to experiments. The current improved force field is expected to have wide applications in the study of ssDNA with nanomaterials including AuNPs, which might help promote the development of ssDNA-based biosensors and other bionano-devices.« less

An improved DNA force field for ssDNA interactions with gold nanoparticles

NASA Astrophysics Data System (ADS)

Jiang, Xiankai; Gao, Jun; Huynh, Tien; Huai, Ping; Fan, Chunhai; Zhou, Ruhong; Song, Bo

2014-06-01

The widespread applications of single-stranded DNA (ssDNA) conjugated gold nanoparticles (AuNPs) have spurred an increasing interest in the interactions between ssDNA and AuNPs. Despite extensive studies using the most sophisticated experimental techniques, the detailed molecular mechanisms still remain largely unknown. Large scale molecular dynamics (MD) simulations can thus be used to supplement experiments by providing complementary information about ssDNA-AuNP interactions. However, up to now, all modern force fields for DNA were developed based on the properties of double-stranded DNA (dsDNA) molecules, which have hydrophilic outer backbones "protecting" hydrophobic inner nucleobases from water. Without the double-helix structure of dsDNA and thus the "protection" by the outer backbone, the nucleobases of ssDNA are directly exposed to solvent, and their behavior in water is very different from that of dsDNA, especially at the interface with nanoparticles. In this work, we have improved the force field of ssDNA for use with nanoparticles, such as AuNPs, based on recent experimental results and quantum mechanics calculations. With the new improved force field, we demonstrated that a poly(A) sequence adsorbed on a AuNP surface is much more stable than a poly(T) sequence, which is consistent with recent experimental observations. On the contrary, the current standard force fields, including AMBER03, CHARMM27, and OPLSAA, all gave erroneous results as compared to experiments. The current improved force field is expected to have wide applications in the study of ssDNA with nanomaterials including AuNPs, which might help promote the development of ssDNA-based biosensors and other bionano-devices.

An improved DNA force field for ssDNA interactions with gold nanoparticles.

PubMed

Jiang, Xiankai; Gao, Jun; Huynh, Tien; Huai, Ping; Fan, Chunhai; Zhou, Ruhong; Song, Bo

2014-06-21

The widespread applications of single-stranded DNA (ssDNA) conjugated gold nanoparticles (AuNPs) have spurred an increasing interest in the interactions between ssDNA and AuNPs. Despite extensive studies using the most sophisticated experimental techniques, the detailed molecular mechanisms still remain largely unknown. Large scale molecular dynamics (MD) simulations can thus be used to supplement experiments by providing complementary information about ssDNA-AuNP interactions. However, up to now, all modern force fields for DNA were developed based on the properties of double-stranded DNA (dsDNA) molecules, which have hydrophilic outer backbones "protecting" hydrophobic inner nucleobases from water. Without the double-helix structure of dsDNA and thus the "protection" by the outer backbone, the nucleobases of ssDNA are directly exposed to solvent, and their behavior in water is very different from that of dsDNA, especially at the interface with nanoparticles. In this work, we have improved the force field of ssDNA for use with nanoparticles, such as AuNPs, based on recent experimental results and quantum mechanics calculations. With the new improved force field, we demonstrated that a poly(A) sequence adsorbed on a AuNP surface is much more stable than a poly(T) sequence, which is consistent with recent experimental observations. On the contrary, the current standard force fields, including AMBER03, CHARMM27, and OPLSAA, all gave erroneous results as compared to experiments. The current improved force field is expected to have wide applications in the study of ssDNA with nanomaterials including AuNPs, which might help promote the development of ssDNA-based biosensors and other bionano-devices.

Discrimination against RNA Backbones by a ssDNA Binding Protein.

PubMed

Lloyd, Neil R; Wuttke, Deborah S

2018-05-01

Pot1 is the shelterin component responsible for the protection of the single-stranded DNA (ssDNA) overhang at telomeres in nearly all eukaryotic organisms. The C-terminal domain of the DNA-binding domain, Pot1pC, exhibits non-specific ssDNA recognition, achieved through thermodynamically equivalent alternative binding conformations. Given this flexibility, it is unclear how specificity for ssDNA over RNA, an activity required for biological function, is achieved. Examination of the ribose-position specificity of Pot1pC shows that ssDNA specificity is additive but not uniformly distributed across the ligand. High-resolution structures of several Pot1pC complexes with RNA-DNA chimeric ligands reveal Pot1pC discriminates against RNA by utilizing non-compensatory binding modes that feature significant rearrangement of the binding interface. These alternative conformations, accessed through both ligand and protein flexibility, recover much, but not all, of the binding energy, leading to the observed reduction in affinities. These findings suggest that intermolecular interfaces are remarkably sophisticated in their tuning of specificity toward flexible ligands. Copyright © 2018 Elsevier Ltd. All rights reserved.

Karl Blumenreuter (1881-1969): Himmler's chief pharmacist and medical supply quartermaster of the SS.

PubMed

Schmidt, M; Gross, D; Westemeier, J

2018-04-02

The present article elucidates the role and function of SS Gruppenführer Karl Blumenreuter (1881-1969), the leading pharmacist of the SS. The aim is to clarify how he participated in the crimes of the Nazi Party and especially the SS during the "Third Reich" and the extent to which he was brought to justice after 1945. Central elements of the study are based on researched archival primary sources. The latter were compared with each other and supplemented with the currently available secondary literature on the subject. It can be established that Blumenreuter was a zealous National Socialist with marked career ambitions who advanced within the SS to the rank of SS Gruppenführer and Lieutenant General of the Waffen SS (Generalleutnant der Waffen SS). He supplied pre-measured phenol ampoules for the murder of prisoners in the concentration camps. Blumenreuter furthermore organised equipment and material supplies for various experiments on humans. After 1945 he succeeded in playing down his participation in the crimes in the time of National Socialism. Blumenreuter died in 1969 without having being brought to justice by the judiciary and without having reflected self-critically on his role in the "Third Reich".

Bithermal Low-Cycle Fatigue Evaluation of Automotive Exhaust System Alloy SS409

NASA Technical Reports Server (NTRS)

Lu, Gui-Ying; Behling, Mike B.; Halford, Gary R.

2000-01-01

This investigation provides, for the first time, cyclic strainrange-controlled, thermomechanical fatigue results for the ferritic stainless steel alloy SS409. The alloy has seen extensive application for automotive exhaust system components. The data were generated to calibrate the Total Strain Version of the Strainrange Partitioning (TS-SRP) method for eventual application to the design and durability assessment of automotive exhaust systems. The thermomechanical cyclic lifetime and cyclic stress-strain constitutive behavior for alloy SS409 were measured using bithermal tests cycling between isothermal extremes of 400 and 800 C. Lives ranged up to 10,000 cycles to failure with hold-times of 0.33 to 2.0 minutes. The bithermal fatigue behavior is compared to isothermal, strain-controlled fatigue behavior at both 400 and 800 C. Thermomechanical cycling was found to have a profound detrimental influence on the fatigue failure resistance of SS409 compared to isothermal cycling. Supplementary bithermal cyclic stress-strain constitutive tests with hold-times ranging from 40 seconds up to 1.5 hours were conducted to calibrate the TS-SRP equation for extrapolation to longer lifetime predictions. Observed thermomechanical (bithermal) fatigue lives correlated well with lives calculated using the calibrated TS-SRP equations: 70% of the bithermal fatigue data fall within a factor of 1.2 of calculated life; 85% within a factor of 1.4; and 100% within a factor of 1.8.

The mass of (1) Ceres from perturbations on (348) May

NASA Technical Reports Server (NTRS)

Williams, Gareth V.

1992-01-01

The most promising ground-based technique for determining the mass of a minor planet is the observation of the perturbations it induces in the motion of another minor planet. This method requires careful observation of both minor planets over extended periods of time. The mass of (1) Ceres has been determined from the perturbations on (348) May, which made three close approaches to Ceres at intervals of 46 years between 1891 and 1984. The motion of May is clearly influenced by Ceres, and by using different test masses for Ceres, a search was made to determine the mass of Ceres that minimizes the residuals in the observations of May.

Optimization of process parameters in the RF-DC plasma N2-H2 for AISI420 molds and dies

NASA Astrophysics Data System (ADS)

Herdianto, Hengky; Djoko, D. J.; Santjojo, H.; Masruroh

2017-11-01

The RF-DC plasma N2-H2 was used to make precise AISI420 molds and dies have complex textured geometry. The quality of the molds and dies directly affect the quality of the produced parts. The excellent examples of molds were used for injection molding lenses and dies used for the precision forging of automotive drive train components. In this study, a temperature, DC bias, and duration as process parameters of the RF-DC plasma N2-H2 have been optimized for molds and dies fabrication. The mask-less micro-patterned method was utilized to draw the initial 2D micro patterns directly onto the AISI420 substrate surface. The unprinted substrate surfaces were selectively nitrided by the RF-DC plasma N2-H2 at 673 K for 5400 s by 70 Pa with hollow cathode device. Energy Dispersive X-ray was utilized to describe the nitrogen content distribution at the vicinity of the border between the unprinted surfaces. This exclusive nitrogen mapping proves that only the unprinted parts of the substrate have high content nitrogen solutes. XRD analysis was performed to investigate whether the iron nitrides were precipitated by RF-DC plasma N2-H2 in the AISI420.

Epigenetic Regulation of Tumor Necrosis Factor α (TNFα) Release in Human Macrophages by HIV-1 Single-stranded RNA (ssRNA) Is Dependent on TLR8 Signaling*

PubMed Central

Han, Xinbing; Li, Xin; Yue, Simon C.; Anandaiah, Asha; Hashem, Falah; Reinach, Peter S.; Koziel, Henry; Tachado, Souvenir D.

2012-01-01

Human macrophages at mucosal sites are essential targets for acute HIV infection. During the chronic phase of infection, they are persistent reservoirs for the AIDS virus. HIV virions gain entry into macrophages following ligation of surface CD4-CCR5 co-receptors, which leads to the release of two copies of HIV ssRNA. These events lead to reverse transcription and viral replication initiation. Toll-like receptors TLR7 and TLR8 recognize specific intracellular viral ssRNA sequences, but in human alveolar macrophages, their individual roles in TLR-mediated HIV ssRNA recognition are unclear. In the current study, HIV-1 ssRNA induced TNFα release in a dose-dependent manner in adherent human macrophages expressing both intracellular TLR7 and TLR8. This response was reduced by inhibiting either endocytosis (50 μm dynasore) or endosomal acidification (1 μg/ml chloroquine). Either MYD88 or TLR8 gene knockdown with relevant siRNA reduced HIV-1 ssRNA-mediated TNFα release, but silencing TLR7 had no effect on this response. Furthermore, HIV-1 ssRNA induced histone 4 acetylation at the TNFα promoter as well as trimethylation of histone 3 at lysine 4, whereas TLR8 gene knockdown reduced these effects. Taken together in human macrophages, TLR8 binds and internalizes HIV ssRNA, leading to endosomal acidification, chromatin remodeling, and increases in TNFα release. Drugs targeting macrophage TLR8-linked signaling pathways may modulate the innate immune response to acute HIV infection by reducing viral replication. PMID:22393042

Middle Level SS&C Energy Series.

ERIC Educational Resources Information Center

Crow, Linda W.; Aldridge, Bill G.

The project on Scope Sequence and Coordination of Secondary School Science (SS&C) was initiated by the National Science Teachers Association (NSTA) and recommends that all students study science every year and advocates carefully sequenced, well-coordinated instruction in biology, chemistry, earth/space science, and physics. This document…

Wear behavior of AISI 1090 steel modified by pulse plasma technique

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

Ayday, Aysun; Durman, Mehmet

2012-09-06

AISI 1090 steel was pulse plasma treated (PPT) using a Molybdenum electrode. Two different pulse numbers were chosen to obtain modified layers of 20{+-}5 {mu}m thickness. The dry sliding wear studies performed on this steel with and without PPT against an alumina ball counterpart showed that the PPT improved the wear resistance. The pulse number of the PPT modified layer was found to be highly influential in imparting the wear resistance to this steel, due to enhancement of surface hardness depending on treatment time.

Previously unknown and highly divergent ssDNA viruses populate the oceans.

PubMed

Labonté, Jessica M; Suttle, Curtis A

2013-11-01

Single-stranded DNA (ssDNA) viruses are economically important pathogens of plants and animals, and are widespread in oceans; yet, the diversity and evolutionary relationships among marine ssDNA viruses remain largely unknown. Here we present the results from a metagenomic study of composite samples from temperate (Saanich Inlet, 11 samples; Strait of Georgia, 85 samples) and subtropical (46 samples, Gulf of Mexico) seawater. Most sequences (84%) had no evident similarity to sequenced viruses. In total, 608 putative complete genomes of ssDNA viruses were assembled, almost doubling the number of ssDNA viral genomes in databases. These comprised 129 genetically distinct groups, each represented by at least one complete genome that had no recognizable similarity to each other or to other virus sequences. Given that the seven recognized families of ssDNA viruses have considerable sequence homology within them, this suggests that many of these genetic groups may represent new viral families. Moreover, nearly 70% of the sequences were similar to one of these genomes, indicating that most of the sequences could be assigned to a genetically distinct group. Most sequences fell within 11 well-defined gene groups, each sharing a common gene. Some of these encoded putative replication and coat proteins that had similarity to sequences from viruses infecting eukaryotes, suggesting that these were likely from viruses infecting eukaryotic phytoplankton and zooplankton.

Periodicity Analysis of X-ray Light Curves of SS 433

NASA Astrophysics Data System (ADS)

Wang, Jun-yi; Lu, Xiang-long; Zhao, Qiu-wen; Dong, Dian-qiao; Lao, Bao-qiang; Lu, Yang; Wei, Yan-heng; Wu, Xiao-cong; An, Tao

2017-01-01

SS 433 is sofar the unique X-ray binary that has the simultaneously detected orbital period, super-orbital period, and nutation period, as well as a bidirectional spiral jet. The study on its X-ray light variability is helpful for understanding the dynamic process of the system, and the correlations between the different wavebands. In this paper, two time-series analysis techniques, i.e., the Lomb-Scargle periodogram and weighted wavelet Z-transform, are employed to search for the periods in the Swift/BAT (Burst Alert Telescope) (15-50 keV) and RXTE/ASM (Rose X-ray Timing Explorer/All Sky Monitor) (1.5-3, 3- 4, and 5-12 keV) light curves of SS 433, and the Monte Carlo simulation is performed for the obtained periodical components. For the 15-50 keV energy band, five significant periodical components are detected, which are P1(∼6.29 d), P2 (∼6.54 d), P3 (∼13.08 d), P4 (∼81.50 d), and P5 (∼162.30 d). For the 3-5 and 5-12 keV energy bands, the periodical components P3 (∼13 d) and P5 (∼162 d) are detected in both energy bands. However, for the 1.5-3 keV energy band, no significant periodic signal is detected. P5 is the strongest periodic signal in the power spectrum for all the energy bands of 3-5, 5-12, and 15-50 keV, and it is consistent with the previous result obtained from the study of optical light curves. Furthermore, in combination with the radio spiral jet of SS 433, it is suggested that the X-ray and optical variability of P5 (∼162 d) is probably related to the precession of its relativistic jet. The high correlation between the X-ray and optical light curves may also imply that the X-ray and optical radiations are of the same physical origin. P3 shows a good agreement with the orbital period (∼13.07 d) obtained by the previous study, and P2 and P4 are respectively the high-frequency harmonics of P3 and P5. P1 is detected only in the power spectrum of the 15-50 keV energy band, and it is consistent with the nutation period of the system. As

Chitin-induced T6SS in Vibrio cholerae is dependent on ChiS activation.

PubMed

Chourashi, Rhishita; Das, Suman; Dhar, Debarpan; Okamoto, Keinosuke; Mukhopadhyay, Asish K; Chatterjee, Nabendu Sekhar

2018-05-01

Vibrio cholerae regularly colonizes the chitinous exoskeleton of crustacean shells in the aquatic region. The type 6 secretion system (T6SS) in V. cholerae is an interbacterial killing device. This system is thought to provide a competitive advantage to V. cholerae in a polymicrobial community of the aquatic region under nutrient-poor conditions. V. cholerae chitin sensing is known to be initiated by the activation of a two-component sensor histidine kinase ChiS in the presence of GlcNAc2 (N,N'-diacetylchitobiose) residues generated by the action of chitinases on chitin. It is known that T6SS in V. cholerae is generally induced by chitin. However, the effect of ChiS activation on T6SS is unknown. Here, we found that ChiS inactivation resulted in impaired bacterial killing and reduced expression of T6SS genes. Active ChiS positively affected T6SS-mediated natural transformation in V. cholerae. ChiS depletion or inactivation also resulted in reduced colonization on insoluble chitin surfaces. Therefore, we have shown that V. cholerae colonization on chitinous surfaces activates ChiS, which promotes T6SS-dependent bacterial killing and horizontal gene transfer. We also highlight the importance of chitinases in T6SS upregulation.

Characterization of Circular ssDNA Viruses within the Echinoderm Nanobiome

NASA Astrophysics Data System (ADS)

Jackson, E.; Bistolas, K. S.; Hewson, I.

2016-02-01

Viral metagenomics has revealed a great diversity and presence of circular single-stranded(ss) DNA viruses most similar to the viral family Circoviridae in various environments both ambient and host. These viruses are an emerging paradigm in viral discovery amongst aquatic invertebrates mainly from the sub-phlya Crustacea and to a lesser extent the phylum Echinodermata. This parasite-host relationship is furthered here with the discovery of circo-like viruses extracted from the tissue of members from the family Holothuroidea (sea cucumbers). Verification and presence of these viruses within the tissue of the host was confirmed through rigorous genome architecture screening and PCR amplification of the rep gene from unamplified viral DNA extracts. Phylogenetic analysis of the rep gene reveals high similarity to circular ssDNA viruses from environmental metagenomic surveys of marine habitats. The significance of these findings is changing the perception and understanding of circular ssDNA viruses by broadening the known host range and blurring certain defining characteristics established by their pathogenic counterparts. Aside from discover and characterization, the potential ecological impacts of ssDNA viruses upon their host remains relatively unknown and further investigations should aim to determine the pathology, route of infection, and ecological implications of viral infection.

Factors Affecting Optimal Surface Roughness of AISI 4140 Steel in Turning Operation Using Taguchi Experiment

NASA Astrophysics Data System (ADS)

Novareza, O.; Sulistiyarini, D. H.; Wiradmoko, R.

2018-02-01

This paper presents the result of using Taguchi method in turning process of medium carbon steel of AISI 4140. The primary concern is to find the optimal surface roughness after turning process. The taguchi method is used to get a combination of factors and factor levels in order to get the optimum surface roughness level. Four important factors with three levels were used in experiment based on Taguchi method. A number of 27 experiments were carried out during the research and analysed using analysis of variance (ANOVA) method. The result of surface finish was determined in Ra type surface roughness. The depth of cut was found to be the most important factors for reducing the surface roughness of AISI 4140 steel. On the contrary, the other important factors i.e. spindle speed and rake side angle of the tool were proven to be less factors that affecting the surface finish. It is interesting to see the effect of coolant composition that gained the second important factors to reduce the roughness. It may need further research to explain this result.

Modeling of the flow stress for AISI H13 Tool Steel during Hard Machining Processes

NASA Astrophysics Data System (ADS)

Umbrello, Domenico; Rizzuti, Stefania; Outeiro, José C.; Shivpuri, Rajiv

2007-04-01

In general, the flow stress models used in computer simulation of machining processes are a function of effective strain, effective strain rate and temperature developed during the cutting process. However, these models do not adequately describe the material behavior in hard machining, where a range of material hardness between 45 and 60 HRC are used. Thus, depending on the specific material hardness different material models must be used in modeling the cutting process. This paper describes the development of a hardness-based flow stress and fracture models for the AISI H13 tool steel, which can be applied for range of material hardness mentioned above. These models were implemented in a non-isothermal viscoplastic numerical model to simulate the machining process for AISI H13 with various hardness values and applying different cutting regime parameters. Predicted results are validated by comparing them with experimental results found in the literature. They are found to predict reasonably well the cutting forces as well as the change in chip morphology from continuous to segmented chip as the material hardness change.

Biodegradable mixed MPEG-SS-2SA/TPGS micelles for triggered intracellular release of paclitaxel and reversing multidrug resistance

PubMed Central

Dong, Kai; Yan, Yan; Wang, Pengchong; Shi, Xianpeng; Zhang, Lu; Wang, Ke; Xing, Jianfeng; Dong, Yalin

2016-01-01

In this study, a type of multifunctional mixed micelles were prepared by a novel biodegradable amphiphilic polymer (MPEG-SS-2SA) and a multidrug resistance (MDR) reversal agent (d-α-tocopheryl polyethylene glycol succinate, TPGS). The mixed micelles could achieve rapid intracellular drug release and reversal of MDR. First, the amphiphilic polymer, MPEG-SS-2SA, was synthesized through disulfide bonds between poly (ethylene glycol) monomethyl ether (MPEG) and stearic acid (SA). The structure of the obtained polymer was similar to poly (ethylene glycol)-phosphatidylethanolamine (PEG-PE). Then the mixed micelles, MPEG-SS-2SA/TPGS, were prepared by MPEG-SS-2SA and TPGS through the thin film hydration method and loaded paclitaxel (PTX) as the model drug. The in vitro release study revealed that the mixed micelles could rapidly release PTX within 24 h under a reductive environment because of the breaking of disulfide bonds. In cell experiments, the mixed micelles significantly inhibited the activity of mitochondrial respiratory complex II, also reduced the mitochondrial membrane potential, and the content of adenosine triphosphate, thus effectively inhibiting the efflux of PTX from cells. Moreover, in the confocal laser scanning microscopy, cellular uptake and 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assays, the MPEG-SS-2SA/TPGS micelles achieved faster release and more uptake of PTX in Michigan Cancer Foundation-7/PTX cells and showed better antitumor effects as compared with the insensitive control. In conclusion, the biodegradable mixed micelles, MPEG-SS-2SA/TPGS, could be potential vehicles for delivering hydrophobic chemotherapeutic drugs in MDR cancer therapy. PMID:27785018

Synergistic Protective Effects of Mitochondrial Division Inhibitor 1 and Mitochondria-Targeted Small Peptide SS31 in Alzheimer's Disease.

PubMed

Reddy, P Hemachandra; Manczak, Maria; Yin, XiangLing; Reddy, Arubala P

2018-01-01

The purpose of our study was to determine the synergistic protective effects of mitochondria-targeted antioxidant SS31 and mitochondria division inhibitor 1 (Mdivi1) in Alzheimer's disease (AD). Using biochemical methods, we assessed mitochondrial function by measuring the levels of hydrogen peroxide, lipid peroxidation, cytochrome c oxidase activity, mitochondrial ATP, and GTPase Drp1 enzymatic activity in mutant AβPP cells. Using biochemical methods, we also measured cell survival and apoptotic cell death. Amyloid-β (Aβ) levels were measured using sandwich ELISA, and using real-time quantitative RT-PCR, we assessed mtDNA (mtDNA) copy number in relation to nuclear DNA (nDNA) in all groups of cells. We found significantly reduced levels of Aβ40 and Aβ42 in mutant AβPP cells treated with SS31, Mdivi1, and SS31+Mdivi1, and the reduction of Aβ42 levels were much higher in SS31+Mdivi1 treated cells than individual treatments of SS31 and Mdivi1. The levels of mtDNA copy number and cell survival were significantly increased in SS31, Mdivi1, and SS31+Mdivi1 treated mutant AβPP cells; however, the increased levels of mtDNA copy number and cell survival were much higher in SS31+Mdivi1 treated cells than individual treatments of SS31 and Mdivi1. Mitochondrial dysfunction is significantly reduced in SS31, Mdivi1, and SS31+Mdivi1 treated mutant AβPP cells; however, the reduction is much higher in cells treated with both SS31+Mdvi1. Similarly, GTPase Drp1 activity is reduced in all treatments, but reduced much higher in SS31+Mdivi1 treated cells. These observations strongly suggest that combined treatment of SS31+Mdivi1 is effective than individual treatments of SS31 and Mdivi1. Therefore, we propose that combined treatment of SS31+Mdivi1 is a better therapeutic strategy for AD. Ours is the first study to investigate combined treatment of mitochondria-targeted antioxidant SS31 and mitochondrial division inhibitor 1 in AD neurons.

Wear and Adhesive Failure of Al2O3 Powder Coating Sprayed onto AISI H13 Tool Steel Substrate

NASA Astrophysics Data System (ADS)

Amanov, Auezhan; Pyun, Young-Sik

2016-07-01

In this study, an alumina (Al2O3) ceramic powder was sprayed onto an AISI H13 hot-work tool steel substrate that was subjected to sanding and ultrasonic nanocrystalline surface modification (UNSM) treatment processes. The significance of the UNSM technique on the adhesive failure of the Al2O3 coating and on the hardness of the substrate was investigated. The adhesive failure of the coating sprayed onto sanded and UNSM-treated substrates was investigated by a micro-scratch tester at an incremental load. It was found, based on the obtained results, that the coating sprayed onto the UNSM-treated substrate exhibited a better resistance to adhesive failure in comparison with that of the coating sprayed onto the sanded substrate. Dry friction and wear property of the coatings sprayed onto the sanded and UNSM-treated substrates were assessed by means of a ball-on-disk tribometer against an AISI 52100 steel ball. It was demonstrated that the UNSM technique controllably improved the adhesive failure of the Al2O3 coating, where the critical load was improved by about 31%. Thus, it is expected that the application of the UNSM technique to an AISI H13 tool steel substrate prior to coating may delay the adhesive failure and improve the sticking between the coating and the substrate thanks to the modified and hardened surface.

Development of Superhydrophobic Material SS 17-4 PH for Bracket Orthodontic Application by Metal Injection Molding

NASA Astrophysics Data System (ADS)

Supriadi, S.; Suharno, B.; Widjaya, T.; Ayuningtyas, S. T.; Baek, E. R.

2018-01-01

Dental’s plaque is a common problem that encountered during orthodontic treatment using bracket. It is caused by demineralization of enamel due to the activity of bacteria. The bacteria increase with remaining excess food which trapped in teeth and bracket. A hydrophobic surface could reduce food attachment on the bracket because of extremely low wettability properties that make it easy to clean with water. There are several methods to obtain hydrophobic surfaces, which are sol-gel, template replica and also etching. The propose of this work is to compare etching treatment and surface modification on sintered SS 17-4 PH as bracket material using CuCl2 and HCl as an etchant while stearic acid was used for surface modification. Hydrophobic surfaces were produced under various etching time i.e 15, 30, 45 and 60 seconds for CuCl2 and 40, 50, 60 and 70 minutes for HCl and also HCl concentration i.e 1,2 and 3 mol/L at room temperature. The hydrophobicity is observed using contact angle measurement while the microstructures observed by Scanning Electron Microscope. The result shows the contact angle could be achieved up to 60% higher than the as-sintered material. Hydrophobic structure has successfully fabricated using etching technique that might be applied to the orthodontic bracket.

Pregnancy outcome in patients with sickle cell disease in the UK--a national cohort study comparing sickle cell anaemia (HbSS) with HbSC disease.

PubMed

Oteng-Ntim, Eugene; Ayensah, Benjamin; Knight, Marian; Howard, Jo

2015-04-01

We describe the findings from a national study of maternal and fetal outcomes of pregnancy in women with sickle cell disease (SCD). Data were collected via the United Kingdom Obstetric Surveillance System between 1 February 2010 and 31 January 2011 from 109 women, of whom 51 (46·8%) had HbSS and 44 (40·4%) had HbSC. Data included antenatal, maternal and fetal outcomes. Comparisons were made between women with HbSS and HbSC. Incidence of complications were acute pain (57%), blood transfusion (26%), urinary tract infection (UTI; 12%) and critical care unit admission (23%) and these were all more common in women with HbSS than HbSC. There was no difference in the incidence of acute chest syndrome, hypertension and venous thromboembolism between HbSS and HbSC. Women with HbSS were more likely to deliver at <37 weeks gestation (P = 0·01) and their babies were more likely to have reduced birth weight. Delivery at <34 weeks was increased in both HbSS and HbSC women (5·9% vs. 4·6%) compared to national data. This study confirms a high rate of maternal and fetal complications in mothers with SCD, even in women with HbSC, which has previously been considered to have a more benign phenotype in pregnancy. © 2014 John Wiley & Sons Ltd.

Electropolymerization of camphorsulfonic acid doped conductive polypyrrole anti-corrosive coating for 304SS bipolar plates

NASA Astrophysics Data System (ADS)

Jiang, Li; Syed, Junaid Ali; Gao, Yangzhi; Zhang, Qiuxiang; Zhao, Junfeng; Lu, Hongbin; Meng, Xiangkang

2017-12-01

Conductive polymer coating doped with large molecular organic acid is an alternative method used to protect stainless steel (SS) bipolar plates in proton exchange membrane fuel cells (PEMFCs). However, it is difficult to select the proper doping acid, which improves the corrosion resistance of the coating without affecting its conductivity. In this study, large spatial molecular group camphorsulfonic acid (CSA) doped polypyrrole (PPY) conductive coating was prepared by galvanostatic electropolymerization on 304SS. The electrochemical properties of the coating were evaluated in 0.1 M H2SO4 solution in order to simulate the PEMFC service environment. The results indicate that the coating increased the corrosion potential and shifted Ecorr towards more positive value, particularly the jcorr value of PPY-CSA coated 304SS was dropped from 97.3 to 0.00187 μA cm-2. The long-term immersion tests (660 h) show that the PPY-CSA coating exhibits better corrosion resistance in comparison with the small acid (SO42-) doped PPY-SO42- or PPY/PPY-SO42- coatings. Moreover, the PPY-CSA coating presents low contact resistance and maintains strong corrosion resistance during the prolonged exposure time due to barrier effect and anodic protection.

Tensile Fracture Behavior and Failure Mechanism of Additively-Manufactured AISI 4140 Low Alloy Steel by Laser Engineered Net Shaping

PubMed Central

Kim, Hoyeol; Liu, Zhichao; Cong, Weilong; Zhang, Hong-Chao

2017-01-01

AISI 4140 powder was directly deposited on AISI 4140 wrought substrate using laser engineered net shaping (LENS) to investigate the compatibility of a LENS-deposited part with the substrate. Tensile testing at room temperature was performed to evaluate the interface bond performance and fracture behavior of the test specimens. All the samples failed within the as-deposited zone, indicating that the interfacial bond is stronger than the interlayer bond inside the deposit. The fracture surfaces were analyzed using scanning electron microscopy (SEM) and energy disperse X-ray spectrometry (EDS). Results show that the tensile fracture failure of the as-deposited part is primarily affected by lack-of-fusion defects, carbide precipitation, and oxide particles inclusions, which causes premature failure of the deposit by deteriorating the mechanical properties and structural integrity. PMID:29120374

Tensile Fracture Behavior and Failure Mechanism of Additively-Manufactured AISI 4140 Low Alloy Steel by Laser Engineered Net Shaping.

PubMed

Kim, Hoyeol; Liu, Zhichao; Cong, Weilong; Zhang, Hong-Chao

2017-11-09

AISI 4140 powder was directly deposited on AISI 4140 wrought substrate using laser engineered net shaping (LENS) to investigate the compatibility of a LENS-deposited part with the substrate. Tensile testing at room temperature was performed to evaluate the interface bond performance and fracture behavior of the test specimens. All the samples failed within the as-deposited zone, indicating that the interfacial bond is stronger than the interlayer bond inside the deposit. The fracture surfaces were analyzed using scanning electron microscopy (SEM) and energy disperse X-ray spectrometry (EDS). Results show that the tensile fracture failure of the as-deposited part is primarily affected by lack-of-fusion defects, carbide precipitation, and oxide particles inclusions, which causes premature failure of the deposit by deteriorating the mechanical properties and structural integrity.

Internal state variable plasticity-damage modeling of AISI 4140 steel including microstructure-property relations: temperature and strain rate effects

NASA Astrophysics Data System (ADS)

Nacif el Alaoui, Reda

Mechanical structure-property relations have been quantified for AISI 4140 steel. under different strain rates and temperatures. The structure-property relations were used. to calibrate a microstructure-based internal state variable plasticity-damage model for. monotonic tension, compression and torsion plasticity, as well as damage evolution. Strong stress state and temperature dependences were observed for the AISI 4140 steel. Tension tests on three different notched Bridgman specimens were undertaken to study. the damage-triaxiality dependence for model validation purposes. Fracture surface. analysis was performed using Scanning Electron Microscopy (SEM) to quantify the void. nucleation and void sizes in the different specimens. The stress-strain behavior exhibited. a fairly large applied stress state (tension, compression dependence, and torsion), a. moderate temperature dependence, and a relatively small strain rate dependence.

SS 433: Total Coverage of 162-Day Precession Phase in Four Years

NASA Technical Reports Server (NTRS)

Band, David L.

1997-01-01

The observations prior to AO-4 covered a number of precession phases, leaving a gap at phase 0.8. In addition, ASCA and previous observations of SS 433 did not observe the spectrum above approx. 10 keV, and consequently the continuum underlying the spectral lines was poorly constrained. Therefore RXTE observations were scheduled for April 1997 to extend the observed spectrum to higher energies; these observations were planned to sample the X-ray lightcurve during the 13.08 day binary period, concentrating on the eclipse of the compact object which emits the jets. We proposed and were awarded ASCA observations simultaneous with the RXTE observations; the purpose of the ASCA observations was to provide greater spectral resolution at the low end of the spectrum observed by RXTE, and to complete the phase coverage of SS 433. As a result of scheduling difficulties early in the mission the RXTE observations were confined to a much shorter time range than originally planned, April 18-91 1997. Optical observations of SS 433 were performed at a number of observatories. The ASCA observations occurred from April 18 13:10 (UT) to April 21 13:20 (UT) for a total effective exposure of 120 ks. The continuum X-ray light curve shows that the ASCA observations started shortly before the ingress into the X-ray partial eclipse, and ended approximately at the time of the egress. Light curves were also obtained for the prominent Fe emission lines in the blue-shifted frame (approaching jet), red-shifted frame (receding jet), and the stationary frame (fluorescent line from the ambient matter). Through the eclipse mapping technique using the light curves, the parameters of the jet emission model were constrained, showing that the kinetic power in the jet exceeds 104? erg s-l. If the energy source is gravitational accretion, as is commonly believed, the derived l;inetic power implies extremely supercritical accretion even for a black; hole with 10M. These results will be described more

Symbolic and Sub-Symbolic Robotic Intelligence Control System (SS-RICS) Users Manual

DTIC Science & Technology

2017-10-01

platform and simulators via either a serial or Transmission Control Protocol (TCP)/IP connection. The implementation of SS-RICS was designed and...box 4.2 SubSim Config Dialog This interface (Fig. 22) is designed to provide execution and property control of all of the subsimprocessors... post fixed with a “_” to designate the end of the variable (e.g., $Line1_memory was found). Example: rTestDollarSign { (* $LookType Distance

Development of TiN particulates reinforced SS316 based metal matrix composite by direct metal laser sintering technique and its characterization

NASA Astrophysics Data System (ADS)

Hussain, Manowar; Mandal, Vijay; Kumar, Vikas; Das, A. K.; Ghosh, S. K.

2017-12-01

The present study describes the fabrication of TiN particulates reinforced SS316 based Metal Matrix Composites (MMCs) in nitrogen and argon atmosphere. The influence of sintering process parameters on microstructure, density, porosity, wear rate and microhardness of the fabricated samples has been analyzed. The input variable process parameters, such as, laser power density (range: 4.13-5.57 W/cm2 (× 104)), scanning speed (range: 3500-4500 mm/min) and the constant parameters, such as, laser beam diameter (0.4 mm), hatching distance (0.2 mm) and layer thickness (0.4 mm) have been considered in the process. It has been observed from Field Emission Scanning Electron Microscopy (FESEM) analysis that TiN and SS316 powder mixture can be sintered in which chromium acts as a binder. Fine gaps are not found at the interface between TiN and SS316 when the mixture is sintered in nitrogen atmosphere. With an increase in the percentage of TiN, the density and wear rate decreases. However, when the reinforcement is taken beyond 18% by weight, the wear rate starts increasing. The microhardness also increases with an increase in the percentage of TiN. The microstructure, elemental compositions and phase characterization of the developed sintered MMCs have been examined by FESEM, EDX (Energy-dispersive X-ray spectroscopy) and XRD (X-ray diffractometer) analysis, respectively. The results have demonstrated the suitability of the TiN reinforced SS316 MMCs for industrial applications.

SS 383: A NEW S-TYPE YELLOW SYMBIOTIC STAR?

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

Baella, N. O.; Pereira, C. B.; Miranda, L. F.

Symbiotic stars are key objects in understanding the formation and evolution of interacting binary systems, and are probably the progenitors of Type Ia supernovae. However, the number of known symbiotic stars is much lower than predicted. We aim to search for new symbiotic stars, with particular emphasis on the S-type yellow symbiotic stars, in order to determine their total population, evolutionary timescales, and physical properties. The Two Micron All Sky Survey (2MASS) (J – H) versus (H – K {sub s}) color-color diagram has been previously used to identify new symbiotic star candidates and show that yellow symbiotics are locatedmore » in a particular region of that diagram. Candidate symbiotic stars are selected on the basis of their locus in the 2MASS (J – H) versus (H – K {sub s}) diagram and the presence of Hα line emission in the Stephenson and Sanduleak Hα survey. This diagram separates S-type yellow symbiotic stars from the rest of the S-type symbiotic stars, allowing us to select candidate yellow symbiotics. To establish the true nature of the candidates, intermediate-resolution spectroscopy is obtained. We have identified the Hα emission line source SS 383 as an S-type yellow symbiotic candidate by its position in the 2MASS color-color diagram. The optical spectrum of SS 383 shows Balmer, He I, He II, and [O III] emission lines, in combination with TiO absorption bands that confirm its symbiotic nature. The derived electron density (≅10{sup 8-9} cm{sup –3}), He I emission line intensity ratios, and position in the [O III] λ5007/Hβ versus [O III] λ4363/Hγ diagram indicate that SS 383 is an S-type symbiotic star, with a probable spectral type of K7-M0 deduced for its cool component based on TiO indices. The spectral type and the position of SS 383 (corrected for reddening) in the 2MASS color-color diagram strongly suggest that SS 383 is an S-type yellow symbiotic. Our result points out that the 2MASS color-color diagram is a powerful

32 CFR Appendix E to Part 246 - Stars and Stripes (S&S) Board of Directors

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 2 2013-07-01 2013-07-01 false Stars and Stripes (S&S) Board of Directors E... DEFENSE (CONTINUED) MISCELLANEOUS STARS AND STRIPES (S&S) NEWSPAPER AND BUSINESS OPERATIONS Pt. 246, App. E Appendix E to Part 246—Stars and Stripes (S&S) Board of Directors A. Organization and Management...

32 CFR Appendix E to Part 246 - Stars and Stripes (S&S) Board of Directors

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 2 2014-07-01 2014-07-01 false Stars and Stripes (S&S) Board of Directors E... DEFENSE (CONTINUED) MISCELLANEOUS STARS AND STRIPES (S&S) NEWSPAPER AND BUSINESS OPERATIONS Pt. 246, App. E Appendix E to Part 246—Stars and Stripes (S&S) Board of Directors A. Organization and Management...

32 CFR Appendix E to Part 246 - Stars and Stripes (S&S) Board of Directors

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 2 2012-07-01 2012-07-01 false Stars and Stripes (S&S) Board of Directors E... DEFENSE (CONTINUED) MISCELLANEOUS STARS AND STRIPES (S&S) NEWSPAPER AND BUSINESS OPERATIONS Pt. 246, App. E Appendix E to Part 246—Stars and Stripes (S&S) Board of Directors A. Organization and Management...

Helicobacter pylori modulates host cell responses by CagT4SS-dependent translocation of an intermediate metabolite of LPS inner core heptose biosynthesis

PubMed Central

Faber, Eugenia; Bats, Simon H.; Murillo, Tatiana; Speidel, Yvonne; Coombs, Nina

2017-01-01

Highly virulent Helicobacter pylori cause proinflammatory signaling inducing the transcriptional activation and secretion of cytokines such as IL-8 in epithelial cells. Responsible in part for this signaling is the cag pathogenicity island (cagPAI) that codetermines the risk for pathological sequelae of an H. pylori infection such as gastric cancer. The Cag type IV secretion system (CagT4SS), encoded on the cagPAI, can translocate various molecules into cells, the effector protein CagA, peptidoglycan metabolites and DNA. Although these transported molecules are known to contribute to cellular responses to some extent, a major part of the cagPAI-induced signaling leading to IL-8 secretion remains unexplained. We report here that biosynthesis of heptose-1,7-bisphosphate (HBP), an important intermediate metabolite of LPS inner heptose core, contributes in a major way to the H. pylori cagPAI-dependent induction of proinflammatory signaling and IL-8 secretion in human epithelial cells. Mutants defective in the genes required for synthesis of HBP exhibited a more than 95% reduction of IL-8 induction and impaired CagT4SS-dependent cellular signaling. The loss of HBP biosynthesis did not abolish the ability to translocate CagA. The human cellular adaptor TIFA, which was described before to mediate HBP-dependent activity in other Gram-negative bacteria, was crucial in the cagPAI- and HBP pathway-induced responses by H. pylori in different cell types. The active metabolite was present in H. pylori lysates but not enriched in bacterial supernatants. These novel results advance our mechanistic understanding of H. pylori cagPAI-dependent signaling mediated by intracellular pattern recognition receptors. They will also allow to better dissect immunomodulatory activities by H. pylori and to improve the possibilities of intervention in cagPAI- and inflammation-driven cancerogenesis. PMID:28715499

Immunization with the recombinant antigen Ss-IR induces protective immunity to infection with Strongyloides stercoralis in mice.

PubMed

Abraham, David; Hess, Jessica A; Mejia, Rojelio; Nolan, Thomas J; Lok, James B; Lustigman, Sara; Nutman, Thomas B

2011-10-19

Human intestinal infections with the nematode Strongyloides stercoralis remain a significant problem worldwide and a vaccine would be a useful addition to the tools available to prevent and control this infection. The goal of this study was to test single antigens for their efficacy in a vaccine against S. stercoralis larvae in mice. Alum was used as the adjuvant in these studies and antigens selected for analysis were either recognized by protective human IgG (Ss-TMY-1, Ss-EAT-6, and Ss-LEC-5) or were known to be highly immunogenic in humans (Ss-NIE-1 and Ss-IR). Only mice immunized with the Ss-IR antigen demonstrated a significant decrease of approximately 80% in the survival of larval parasites in the challenge infection. Antibodies, recovered from mice with protective immunity to S. stercoralis after immunization with Ss-IR, were used to locate the antigen in the larvae. Confocal microscopy revealed that IgG from mice immunized with Ss-IR bound to the surface of the parasites and observations by electron microscopy indicated that IgG bound to granules in the glandular esophagus. Serum collected from mice immunized with Ss-IR passively transferred immunity to naïve mice. These studies demonstrate that Ss-IR, in combination with alum, induces high levels of protective immunity through an antibody dependent mechanism and may therefore be suitable for further development as a vaccine against human strongyloidiasis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Integrated Composite Stiffener Structure (ICoSS) Concept for Planetary Entry Vehicles

NASA Technical Reports Server (NTRS)

Kellas, Sotiris

2016-01-01

Results from the design, manufacturing, and testing of a lightweight Integrated Composite Stiffened Structure (ICoSS) concept, intended for multi-mission planetary entry vehicles are presented. Tests from both component and full-scale tests for a typical Earth Entry Vehicle forward shell manufactured using the ICoSS concept are presented and advantages of the concept for the particular application of passive Earth Entry Vehicles over other structural concepts are discussed.

Mild achondroplasia/hypochondroplasia with acanthosis nigricans, normal development, and a p.Ser348Cys FGFR3 mutation.

PubMed

Couser, Natario L; Pande, Chetna K; Turcott, Christie M; Spector, Elaine B; Aylsworth, Arthur S; Powell, Cynthia M

2017-04-01

Pathogenic allelic variants in the fibroblast growth factor receptor 3 (FGFR3) gene have been associated with a number of phenotypes including achondroplasia, hypochondroplasia, thanatophoric dysplasia, Crouzon syndrome with acanthosis nigricans (Crouzonodermoskeletal syndrome), and SADDAN (severe achondroplasia with developmental delay and acanthosis nigricans). Crouzon syndrome with acanthosis nigricans is caused by the pathogenic variant c.1172C>A (p.Ala391Glu) in the FGFR3 gene. The p.Lys650Thr pathogenic variant in FGFR3 has been linked to acanthosis nigricans without significant craniofacial or skeletal abnormalities. Recently, an infant with achondroplasia and a novel p.Ser348Cys FGFR3 mutation was reported. We describe the clinical history of an 8-year-old child with a skeletal dysplasia in the achondroplasia-hypochondroplasia spectrum, acanthosis nigricans, typical development, and the recently described p.Ser348Cys FGFR3 mutation. © 2017 Wiley Periodicals, Inc.

Effect of Continuous and Pulsed Current Gas Tungsten Arc Welding on Dissimilar Weldments Between Hastelloy C-276/AISI 321 Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Sharma, Sumitra; Taiwade, Ravindra V.; Vashishtha, Himanshu

2017-03-01

In the present investigation, an attempt has been made to join Hastelloy C-276 nickel-based superalloy and AISI 321 austenitic stainless steel using ERNiCrMo-4 filler. The joints were fabricated by continuous and pulsed current gas tungsten arc welding processes. Experimental studies to ascertain the structure-property co-relationship with or without pulsed current mode were carried out using an optical microscope and scanning electron microscope. Further, the energy-dispersive spectroscope was used to evaluate the extent of microsegregation. The microstructure of fusion zone was obtained as finer cellular dendritic structure for pulsed current mode, whereas columnar structure was formed with small amount of cellular structure for continuous current mode. The scanning electron microscope examination witnessed the existence of migrated grain boundaries at the weld interfaces. Moreover, the presence of secondary phases such as P and μ was observed in continuous current weld joints, whereas they were absent in pulsed current weld joints, which needs to be further characterized. Moreover, pulsed current joints resulted in narrower weld bead, refined morphology, reduced elemental segregation and improved strength of the welded joints. The outcomes of the present investigation would help in obtaining good quality dissimilar joints for industrial applications and AISI 321 ASS being cheaper consequently led to cost-effective design also.

In vivo fate of 125I SS-B (La) injected into mice.

PubMed Central

Schrieber, L; Erhardt, C C; Melsom, R D; Venables, P J; McCarthy, D A; Mumford, P A; Horsfall, A C; Maini, R N

1983-01-01

The fate of the radiolabelled soluble cellular antigen SS-B (La) was compared with that of other 125I-labelled proteins of known molecular weight (MW) and electrostatic charge, following i.v. injection into BALB/c mice. The plasma half-life of 125I-SS-B was 3 min, while that of 125I-bovine serum albumin (similar MW and electrostatic charge) was 270 min. 125I-heat-aggregated IgG (MW greater than 1 x 10(6)) and 125I-7S human IgG (MW 168,000) had plasma half-lives of 40 min and greater than 300 min, respectively. Liver and kidney showed preferential uptake of 125I-SS-B, followed by a rapid decrease in radioactivity. During this time low MW, trichloroacetic acid (TCA) soluble, material appeared in urine. This suggests a specific uptake mechanism followed by a catabolic phase. These studies demonstrate that normal mice remove 125I-SS-B rapidly from the circulation and then degrade it. This rapid antigen elimination may protect against the induction of potentially harmful autoantibody responses. PMID:6832805

Corrosion studies of DC reactive magnetron sputtered alumina coating on 304 SS

NASA Astrophysics Data System (ADS)

Thangaraj, Baskar; Mahadevan, Krishnan

2017-12-01

Aluminum oxide films on SS 304 deposited by DC reactive magnetron sputtering technique were studied with respect to the composition of the sputter gas (Ar:O2), gas pressure, substrate temperature, current etc. to achieve good insulating films with high corrosion resistance. The films were characterized by XRD and SEM techniques. Potentiodynamic polarization and electrochemical impedance spectroscopy measurements were made under static conditions in order to evaluate the corrosion performance of the alumina-coated SS 304 for various immersion durations in 0.5 M and 1 M NaCl solution. Alumina-coated SS 304 has low corrosion value of 0.4550 and 1.1090MPY for 24 h immersion time in both solutions. The impedance plots for the alumina coated SS 304 in 1 M NaCl solution at different durations are slightly different to when compared to its immersion in 0.5 M NaCl solutions and are composed of two depressed semi circles. For the alumina coated film, the impedance spectrum decreased, when immersion time increased.

Evaluation of corrosion products formed by sulfidation as inhibitors of the naphthenic corrosion of AISI-316 steel

NASA Astrophysics Data System (ADS)

Sanabria-Cala, J. A.; Montañez, N. D.; Laverde Cataño, D.; Y Peña Ballesteros, D.; Mejía, C. A.

2017-12-01

Naphthenic acids present in oil from most regions worldwide currently stand as the main responsible for the naphthenic corrosion problems, affecting the oil-refining industry. The phenomenon of sulfidation, accompanying corrosion processes brought about by naphthenic acids in high-temperature refining plant applications, takes place when the combination of sulfidic acid (H2S) with Fe forms layers of iron sulphide (FeS) on the material surface, layers with the potential to protect the material from attack by other corrosive species like naphthenic acids. This work assessed corrosion products formed by sulfidation as inhibitors of naphthenic corrosion rate in AISI-316 steel exposed to processing conditions of simulated crude oil in a dynamic autoclave. Calculation of the sulfidation and naphthenic corrosion rates were determined by gravimetry. The surfaces of the AISI-316 gravimetric coupons exposed to acid systems; were characterized morphologically by X-Ray Diffraction (XRD) and X-ray Fluorescence by Energy Dispersive Spectroscopy (EDS) combined with Scanning Electron Microscopy (SEM). One of the results obtained was the determination of an inhibiting effect of corrosion products at 250 and 300°C, where lower corrosion rate levels were detected. For the temperature of 350°C, naphthenic corrosion rates increased due to deposition of naphthenic acids on the areas where corrosion products formed by sulfidation have lower homogeneity and stability on the surface, thus accelerating the destruction of AISI-316 steel. The above provides an initial contribution to oil industry in search of new alternatives to corrosion control by the attack of naphthenic acids, from the formation of FeS layers on exposed materials in the processing of heavy crude oils with high sulphur content.

A Computational Study of Plastic Deformation in AISI 304 Induced by Surface Mechanical Attrition Treatment

NASA Astrophysics Data System (ADS)

Zhang, X. C.; Lu, J.; Shi, S. Q.

2010-05-01

As a technique of grain refinement process by plastic deformation, surface mechanical attrition treatment (SMAT) has been developed to be one of the most effective ways to optimize the mechanical properties of various materials including pure metals and alloys. SMAT can significantly reduce grain size into nanometer regime in the surface layer of bulk materials, providing tremendous opportunities for improving physical, chemical and mechanical properties of the materials. In this work, a computational modeling of the surface mechanical attrition treatment (SMAT) process is presented, in which Johnson-Cook plasticity model and the finite element method were employed to study the high strain rate, elastic-plastic dynamic process of ball impact on a metallic target. AISI 304 steel with low stacking fault energy was chosen as the target material. First, a random impact model was used to analyze the statistic characteristics of ball impact, and then the plastic deformation behavior and residual stress distribution in AISI 304 stainless steel during SMAT were studied. The simulation results show that the compressive residual stress and vertical deformation of the surface structures were directly affected by ball impact frequency, incident impact angle and ball diameter used in SMAT process.

An Ss Model with Adverse Selection.

ERIC Educational Resources Information Center

House, Christopher L.; Leahy, John V.

2004-01-01

We present a model of the market for a used durable in which agents face fixed costs of adjustment, the magnitude of which depends on the degree of adverse selection in the secondary market. We find that, unlike typical models, the sS bands in our model contract as the variance of the shock increases. We also analyze a dynamic version of the model…

INFRARED SPECTROSCOPY OF SYMBIOTIC STARS. X. ORBITS FOR THREE S-TYPE SYSTEMS: V1044 CENTAURI, HEN 3-1213, AND SS 73-96

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

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

Employing new infrared radial velocities, we have computed orbits of the cool giants in three southern S-type symbiotic systems. The orbit for V1044 Cen, an M5.5 giant, has a period of 985 days and a modest eccentricity of 0.16. Hen 3-1213 is a K4 giant, yellow symbiotic with an orbital period of 533 days and a similar eccentricity of 0.18. For the M2 giant SS 73-96 the orbital period is 828 days, and this system has a somewhat larger eccentricity of 0.26. Measurement of the H i Paschen δ emission lines, which may at least partially reflect the motion ofmore » the secondary in SS 73-96, results in a mass ratio of 2.4 for the M giant relative to the presumed white dwarf. The estimated orbital inclinations of V1044 Cen and Hen 3-1213 are low, about 40°. However, for SS 73-96 the predicted inclination is 90°, and so an ephemeris for eclipses of the secondary or the hot nebula surrounding it is provided. A search of the orbital velocity residuals of V1044 Cen and SS 73-96 for pulsation periods produced no realistic or convincing period for either star.« less

Investigation of Low-Cycle Bending Fatigue of AISI 9310 Steel Spur Gears

NASA Technical Reports Server (NTRS)

Handschuh, Robert F.; Krantz, Timothy L.; Lerch, Bradley A.; Burke, Christopher S.

2007-01-01

An investigation of the low-cycle bending fatigue of spur gears made from AISI 9310 gear steel was completed. Tests were conducted using the single-tooth bending method to achieve crack initiation and propagation. Tests were conducted on spur gears in a fatigue test machine using a dedicated gear test fixture. Test loads were applied at the highest point of single tooth contact. Gear bending stresses for a given testing load were calculated using a linear-elastic finite element model. Test data were accumulated from 1/4 cycle to several thousand cycles depending on the test stress level. The relationship of stress and cycles for crack initiation was found to be semi-logarithmic. The relationship of stress and cycles for crack propagation was found to be linear. For the range of loads investigated, the crack propagation phase is related to the level of load being applied. Very high loads have comparable crack initiation and propagation times whereas lower loads can have a much smaller number of cycles for crack propagation cycles as compared to crack initiation.

Investigation of Low-Cycle Bending Fatigue of AISI 9310 Steel Spur Gears

NASA Technical Reports Server (NTRS)

Handschuh, Robert F.; Krantz, Timothy L.; Lerch, Bradley A.; Burke, Christopher S.

2007-01-01

An investigation of the low-cycle bending fatigue of spur gears made from AISI 9310 gear steel was completed. Tests were conducted using the single-tooth bending method to achieve crack initiation and propagation. Tests were conducted on spur gears in a fatigue test machine using a dedicated gear test fixture. Test loads were applied at the highest point of single tooth contact. Gear bending stresses for a given testing load were calculated using a linear-elastic finite element model. Test data were accumulated from 1/4 cycle to several thousand cycles depending on the test stress level. The relationship of stress and cycles for crack initiation was found to be semilogarithmic. The relationship of stress and cycles for crack propagation was found to be linear. For the range of loads investigated, the crack propagation phase is related to the level of load being applied. Very high loads have comparable crack initiation and propagation times whereas lower loads can have a much smaller number of cycles for crack propagation cycles as compared to crack initiation.

Experimental investigation of various surface integrity aspects in hard turning of AISI 4340 alloy steel with coated and uncoated cermet

NASA Astrophysics Data System (ADS)

Das, Anshuman; Patel, S. K.; Sateesh Kumar, Ch.; Biswal, B. B.

2018-03-01

The newer technological developments are exerting immense pressure on domain of production. These fabrication industries are busy finding solutions to reduce the costs of cutting materials, enhance the machined parts quality and testing different materials, which can be made versatile for cutting materials, which are difficult for machining. High-speed machining has been the domain of paramount importance for mechanical engineering. In this study, the variation of surface integrity parameters of hardened AISI 4340 alloy steel was analyzed. The surface integrity parameters like surface roughness, micro hardness, machined surface morphology and white layer of hardened AISI 4340 alloy steel were compared using coated and uncoated cermet inserts under dry cutting condition. From the results, it was deduced that coated insert outperformed uncoated one in terms of different surface integrity characteristics.

Excessive Counterion Condensation on Immobilized ssDNA in Solutions of High Ionic Strength

PubMed Central

Rant, Ulrich; Arinaga, Kenji; Fujiwara, Tsuyoshi; Fujita, Shozo; Tornow, Marc; Yokoyama, Naoki; Abstreiter, Gerhard

2003-01-01

We present experiments on the bias-induced release of immobilized, single-stranded (ss) 24-mer oligonucleotides from Au-surfaces into electrolyte solutions of varying ionic strength. Desorption is evidenced by fluorescence measurements of dye-labeled ssDNA. Electrostatic interactions between adsorbed ssDNA and the Au-surface are investigated with respect to 1), a variation of the bias potential applied to the Au-electrode; and 2), the screening effect of the electrolyte solution. For the latter, the concentration of monovalent salt in solution is varied from 3 to 1600 mM. We find that the strength of electric interaction is predominantly determined by the effective charge of the ssDNA itself and that the release of DNA mainly occurs before the electrochemical double layer has been established at the electrolyte/Au interface. In agreement with Manning's condensation theory, the measured desorption efficiency (ηrel) stays constant over a wide range of salt concentrations; however, as the Debye length is reduced below a value comparable to the axial charge spacing of the DNA, ηrel decreases substantially. We assign this effect to excessive counterion condensation on the DNA in solutions of high ionic strength. In addition, the relative translational diffusion coefficient of ssDNA in solution is evaluated for different salt concentrations. PMID:14645075

Excessive counterion condensation on immobilized ssDNA in solutions of high ionic strength.

PubMed

Rant, Ulrich; Arinaga, Kenji; Fujiwara, Tsuyoshi; Fujita, Shozo; Tornow, Marc; Yokoyama, Naoki; Abstreiter, Gerhard

2003-12-01

We present experiments on the bias-induced release of immobilized, single-stranded (ss) 24-mer oligonucleotides from Au-surfaces into electrolyte solutions of varying ionic strength. Desorption is evidenced by fluorescence measurements of dye-labeled ssDNA. Electrostatic interactions between adsorbed ssDNA and the Au-surface are investigated with respect to 1), a variation of the bias potential applied to the Au-electrode; and 2), the screening effect of the electrolyte solution. For the latter, the concentration of monovalent salt in solution is varied from 3 to 1600 mM. We find that the strength of electric interaction is predominantly determined by the effective charge of the ssDNA itself and that the release of DNA mainly occurs before the electrochemical double layer has been established at the electrolyte/Au interface. In agreement with Manning's condensation theory, the measured desorption efficiency (etarel) stays constant over a wide range of salt concentrations; however, as the Debye length is reduced below a value comparable to the axial charge spacing of the DNA, etarel decreases substantially. We assign this effect to excessive counterion condensation on the DNA in solutions of high ionic strength. In addition, the relative translational diffusion coefficient of ssDNA in solution is evaluated for different salt concentrations.

Novel Immunocytokine IL12-SS1 (Fv) Inhibits Mesothelioma Tumor Growth in Nude Mice

PubMed Central

Kim, Heungnam; Gao, Wei; Ho, Mitchell

2013-01-01

Mesothelin is a glycosylphosphatidylinositol-anchored glycoprotein that is highly expressed on the cell surface of malignant mesothelioma. Monoclonal antibodies against mesothelin are being evaluated for the treatment of mesothelioma. Immunocytokines represent a novel class of armed antibodies. To provide an alternative approach to current mesothelin-targeted antibody therapies, we have developed a novel immunocytokine based on interleukin-12 (IL12) and the SS1 Fv specific for mesothelin. IL12 possesses potent anti-tumor activity in a wide variety of solid tumors. The newly-developed recombinant immunocytokine, IL12-SS1 (Fv), was produced in insect cells using a baculovirus-insect cell expression system. The SS1 single-chain Fv was fused to the C terminus of the p35 subunit of IL12 through a short linker (GSADGG). The single-chain IL12-SS1 (Fv) immunocytokine bound native mesothelin proteins on malignant mesothelioma (NCI-H226) and ovarian (OVCAR-3) cells as well as recombinant mesothelin on A431/H9 cells. The immunocytokine retained sufficient bioactivity of IL12 and significantly inhibited human malignant mesothelioma (NCI-H226) grown in the peritoneal cavity of nude mice and showed comparable anti-tumor activity to that of the SS1P immunotoxin. IL12-SS1 (Fv) is the first reported immunocytokine to mesothelin-positive tumors and may be an attractive addition to mesothelin-targeted cancer therapies. PMID:24260587

Rapid detection of ssDNA and RNA using multi-walled carbon nanotubes modified screen-printed carbon electrode.

PubMed

Ye, Yongkang; Ju, Huangxian

2005-11-15

A method for rapid sensitive detection of DNA or RNA was designed using a composite screen-printed carbon electrode modified with multi-walled carbon nanotubes (MWNTs). MWNTs showed catalytic characteristics for the direct electrochemical oxidation of guanine or adenine residues of signal strand DNA (ssDNA) and adenine residues of RNA, leading to indicator-free detection of ssDNA and RNA concentrations. With an accumulation time of 5 min, the proposed method could be used for detection of calf thymus ssDNA ranging from 17.0 to 345 microg ml(-1) with a detection limit of 2.0 microg ml(-1) at 3 sigma and yeast tRNA ranging from 8.2 microg ml(-1) to 4.1 mg ml(-1). AC impedance was employed to characterize the surface of modified electrodes. The advantages of convenient fabrication, low-cost detection, short analysis time and combination with nanotechnology for increasing the sensitivity made the subject worthy of special emphasis in the research programs and sources of new commercial products.

12 CFR 348.4 - Interlocking relationships permitted by statute.

Code of Federal Regulations, 2011 CFR

2011-01-01

... authorized on an emergency basis in accordance with section 13(k) of the Federal Deposit Insurance Act (12 U... 12 Banks and Banking 4 2011-01-01 2011-01-01 false Interlocking relationships permitted by statute... function; (b) A corporation operating under section 25 or section 25A of the Federal Reserve Act (12 U.S.C...

Toxicity of Neurons Treated with Herbicides and Neuroprotection by Mitochondria-Targeted Antioxidant SS31

PubMed Central

Reddy, Tejaswini P.; Manczak, Maria; Calkins, Marcus J.; Mao, Peizhong; Reddy, Arubala P.; Shirendeb, Ulziibat; Park, Byung; Reddy, P. Hemachandra

2011-01-01

The purpose of this study was to determine the neurotoxicity of two commonly used herbicides: picloram and triclopyr and the neuroprotective effects of the mitochondria-targeted antioxidant, SS31. Using mouse neuroblastoma (N2a) cells and primary neurons from C57BL/6 mice, we investigated the toxicity of these herbicides, and protective effects of SS1 peptide against picloram and triclopyr toxicity. We measured total RNA content, cell viability and mRNA expression of peroxiredoxins, neuroprotective genes, mitochondrial-encoded electron transport chain (ETC) genes in N2a cells treated with herbicides and SS31. Using primary neurons from C57BL/6 mice, neuronal survival was studied in neurons treated with herbicides, in neurons pretreated with SS31 plus treated with herbicides, neurons treated with SS31 alone, and untreated neurons. Significantly decreased total RNA content, and cell viability in N2a cells treated with picloram and triclopyr were found compared to untreated N2a cells. Decreased mRNA expression of neuroprotective genes, and ETC genes in cells treated with herbicides was found compared to untreated cells. Decreased mRNA expression of peroxiredoxins 1–6 in N2a cells treated with picloram was found, suggesting that picloram affects the antioxidant enzymes in N2a cells. Immunofluorescence analysis of primary neurons revealed that decreased neuronal branching and degenerating neurons in neurons treated with picloram and triclopyr. However, neurons pretreated with SS31 prevented degenerative process caused by herbicides. Based on these results, we propose that herbicides—picloram and triclopyr appear to damage neurons, and the SS31 peptide appears to protect neurons from herbicide toxicity. PMID:21318024

Effectiveness of bomber deployed autonomous airborne vehicles in finding rail mobile SS-24s

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

Abey, A.E.; Erickson, S.A.; Norquist, P.D.

1990-08-01

Computer simulation predictions of the effectiveness of autonomous airborne vehicles in finding rail mobile SS-24s are presented. Effectiveness is discussed for several autonomous airborne vehicle endurances and survivabilities for the search area southwest of Moscow. The effect of where the Soviets place the SS-24s on the rail network was also investigated. The simulation predicts significant variations in the ability of a multi-autonomous airborne vehicle system to find SS-24s with these parameters. 12 figs., 1 tab.

[Fool's gold standards in language screening. Sensitivity and specificity of the Hessian child language screening test (Kindersprachscreening, KiSS)].

PubMed

Neumann, K; Holler-Zittlau, I; van Minnen, S; Sick, U; Zaretsky, Y; Euler, H A

2011-01-01

The German Kindersprachscreening (KiSS) is a universal speech and language screening test for large-scale identification of Hessian kindergarten children requiring special educational language training or clinical speech/language therapy. To calculate the procedural screening validity, 257 children (aged 4.0 to 4.5 years) were tested using KiSS and four language tests (Reynell Development Language Scales III, Patholinguistische Diagnostik, PLAKSS, AWST-R). The majority or consensus judgements of three speech-language professionals, based on the language test results, served as a reference criterion. The base (fail) rates of the professionals were either self-determined or preset based on known prevalence rates. Screening validity was higher for preset than for self-determined base rates due to higher inter-judge agreement. The confusion matrices of the overall index classification of the KiSS (speech-language abnormalities with educational or clinical needs) with the fixed base rate expert judgement about language impairment, including fluency or voice disorders, yielded a sensitivity of 88% and a specificity of 78%, for just language impairment 84% and 75%, respectively. Specificities for disorders requiring clinical diagnostics in the KiSS (language impairment alone or combined with fluency/voice disorders) related to the test-based consensus expert judgment was about 93%. Sensitivities were unsatisfactory because the differentiation between educational and clinical needs requires improvement. Since the judgement concordances between the speech-language professionals was only moderate, the development of a comprehensive German reference test for speech and language disorders with evidence-based algorithmic decision rules rather than subjective clinical judgement is advocated.

Nuclear processes in the jets of SS 433

NASA Technical Reports Server (NTRS)

Ramaty, R.; Kozlovsky, B.; Lingenfelter, R. E.

1984-01-01

The very narrow gamma-ray lines observed at 1.495 and 6.695 MeV from SS 433 which are blueshifted 1.369 and 6.129 emissions from deexcitations of (24)Mg-asterisk and (16)O-asterisk in grains moving with the jets and inelastically excited by interactions with the ambient medium are discussed. Energetic particle interactions in grains produce very narrow gamma ray lines from deexcitation of nuclear levels whose lifetimes are long enough that the excited nuclei stop before deexcitation. The presence of grains in the jets resolves hitherto discussed difficulties of inelastic excitation models for gamma ray production in SS 433, the very narrow widths of the observed lines and the absence of other strong lines, expected from abundant elements. A model is proposed which could be distinguished from a previously proposed fusion model by gamma ray line observations.

Nuclear processes in the jets of SS433

NASA Technical Reports Server (NTRS)

Ramaty, R.; Kozlovsky, B.; Lingenfelter, R. E.

1984-01-01

The very narrow gamma-ray lines observed at 1.495 and 6.695 MeV from SS433 which are blueshifted 1.369 and 6.129 emissions from deexcitations of (24)Mg* and (16)O* in grains moving with the jets and inelastically excited by interactions with the ambient medium are discussed. Energetic particle interactions in grains produce very narrow gamma ray lines from deexcitation of nuclear levels whose lifetimes are long enough that the excited nuclei stop before deexcitation. The presence of grains in the jets resolves hitherto discussed difficulties of inelastic excitation models for gamma ray production in SS433, the very narrow widths of the observed lines and the absence of other strong lines, expected from abundant elements. A model is proposed which could be distinguished from a previously proposed fusion model by gamma ray line observations.

Drilling into the deep interior of the Nankai accretionary prism: Preliminary results of IODP NanTroSEIZE Expedition 348

NASA Astrophysics Data System (ADS)

Tobin, H. J.; Hirose, T.; Saffer, D. M.; Toczko, S.; Maeda, L.

2014-12-01

International Ocean Discovery Program (IODP) Expedition 348, the latest advance of the NanTroSEIZE project, started on 13 September 2013 and was completed on 29 January 2014. During Expedition 348, the drilling vessel Chikyu advanced the ultra-deep riser hole at Site C0002, located 80 km offshore of the Kii Peninsula, from a depth of 860 meters below sea floor (mbsf) to 3058.5 mbsf, the world record for the deepest scientific ocean drilling, and cased it for future deepening. The drilling operation successfully obtained data on formation physical properties from logging while drilling (LWD) tools, as well as from lithological analyses of cuttings and core from the interior of the active accretionary prism at the Nankai Trough. IODP Site C0002 is the currently only borehole to access the deep interior of an active convergent margin. Preliminary scientific results of Expedition 348 are as follows: (1) Fine-grained turbiditic mudstones with coarser silty and sandy interbeds, exhibiting steep dips (between ~60 and 90 degrees) are predominant in the prism down to ~3000 mbsf. The biostratigraphic age of the sediments in the lowermost part of the hole is thought to be 9-11 Ma, with an assumed age of accretion of 3-5 Ma. (2) Slickenlined surfaces, deformation bands and mineral veins are present throughout the drilled interval, while well-developed scaly clay fabrics are increasingly observed below ~2200 mbsf. A substantial fault zone with well-developed foliation was successfully cored from the deep interior of the prism at ~2205 mbsf. (3) Porosity generally decreases from ~60% to ~20% from the seafloor to 3000 mbsf. However, physical properties including grain density, electrical conductivity and P-wave velocity suggest fairly homogeneous properties in the interior of the prism between ~2000 and 3000 mbsf. (4) Mud gas analysis during the riser drilling indicates that a source of methane gas shifts from microbial origin to thermogenic at around 2325 mbsf. (5) The maximum

Validity of Automated Choroidal Segmentation in SS-OCT and SD-OCT.

PubMed

Zhang, Li; Buitendijk, Gabriëlle H S; Lee, Kyungmoo; Sonka, Milan; Springelkamp, Henriët; Hofman, Albert; Vingerling, Johannes R; Mullins, Robert F; Klaver, Caroline C W; Abràmoff, Michael D

2015-05-01

To evaluate the validity of a novel fully automated three-dimensional (3D) method capable of segmenting the choroid from two different optical coherence tomography scanners: swept-source OCT (SS-OCT) and spectral-domain OCT (SD-OCT). One hundred eight subjects were imaged using SS-OCT and SD-OCT. A 3D method was used to segment the choroid and quantify the choroidal thickness along each A-scan. The segmented choroidal posterior boundary was evaluated by comparing to manual segmentation. Differences were assessed to test the agreement between segmentation results of the same subject. Choroidal thickness was defined as the Euclidian distance between Bruch's membrane and the choroidal posterior boundary, and reproducibility was analyzed using automatically and manually determined choroidal thicknesses. For SS-OCT, the average choroidal thickness of the entire 6- by 6-mm2 macular region was 219.5 μm (95% confidence interval [CI], 204.9-234.2 μm), and for SD-OCT it was 209.5 μm (95% CI, 197.9-221.0 μm). The agreement between automated and manual segmentations was high: Average relative difference was less than 5 μm, and average absolute difference was less than 15 μm. Reproducibility of choroidal thickness between repeated SS-OCT scans was high (coefficient of variation [CV] of 3.3%, intraclass correlation coefficient [ICC] of 0.98), and differences between SS-OCT and SD-OCT results were small (CV of 11.0%, ICC of 0.73). We have developed a fully automated 3D method for segmenting the choroid and quantifying choroidal thickness along each A-scan. The method yielded high validity. Our method can be used reliably to study local choroidal changes and may improve the diagnosis and management of patients with ocular diseases in which the choroid is affected.

Parameter Optimization Of Natural Hydroxyapatite/SS316l Via Metal Injection Molding (MIM)

NASA Astrophysics Data System (ADS)

Mustafa, N.; Ibrahim1, M. H. I.; Amin, A. M.; Asmawi, R.

2017-01-01

Metal injection molding (MIM) are well known as a worldwide application of powder injection molding (PIM) where as applied the shaping concept and the beneficial of plastic injection molding but develops the applications to various high performance metals and alloys, plus metal matrix composites and ceramics. This study investigates the strength of green part by using stainless steel 316L/ Natural hydroxyapatite composite as a feedstock. Stainless steel 316L (SS316L) was mixed with Natural hydroxyapatite (NHAP) by adding 40 wt. % Low Density Polyethylene and 60 %wt. Palm Stearin as a binder system at 63 wt. % powder loading consist of 90 % wt. of SS316 L and 10 wt. % NHAP prepared thru critical powder volume percentage (CPVC). Taguchi method was functional as a tool in determining the optimum green strength for Metal Injection Molding (MIM) parameters. The green strength was optimized with 4 significant injection parameter such as Injection temperature (A), Mold temperature (B), Pressure (C) and Speed (D) were selected throughout screening process. An orthogonal array of L9 (3)4 was conducted. The optimum injection parameters for highest green strength were established at A1, B2, C0 and D1 and where as calculated based on Signal to Noise Ratio.

Safe and effective error rate monitors for SS7 signaling links

NASA Astrophysics Data System (ADS)

Schmidt, Douglas C.

1994-04-01

This paper describes SS7 error monitor characteristics, discusses the existing SUERM (Signal Unit Error Rate Monitor), and develops the recently proposed EIM (Error Interval Monitor) for higher speed SS7 links. A SS7 error monitor is considered safe if it ensures acceptable link quality and is considered effective if it is tolerant to short-term phenomena. Formal criteria for safe and effective error monitors are formulated in this paper. This paper develops models of changeover transients, the unstable component of queue length resulting from errors. These models are in the form of recursive digital filters. Time is divided into sequential intervals. The filter's input is the number of errors which have occurred in each interval. The output is the corresponding change in transmit queue length. Engineered EIM's are constructed by comparing an estimated changeover transient with a threshold T using a transient model modified to enforce SS7 standards. When this estimate exceeds T, a changeover will be initiated and the link will be removed from service. EIM's can be differentiated from SUERM by the fact that EIM's monitor errors over an interval while SUERM's count errored messages. EIM's offer several advantages over SUERM's, including the fact that they are safe and effective, impose uniform standards in link quality, are easily implemented, and make minimal use of real-time resources.

Binding of antibodies to the extractable nuclear antigens SS-A/Ro and SS-B/La is induced on the surface of human keratinocytes by ultraviolet light (UVL): Implications for the pathogenesis of photosensitive cutaneous lupus

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

Furukawa, F.; Kashihara-Sawami, M.; Lyons, M.B.

1990-01-01

Autoantibodies to the non-histone nucleoprotein antigens SS-A/Ro, SS-B/La, and RNP are highly associated with photosensitive cutaneous lupus erythematosus (LE). In order to better understand the potential mechanisms of ultraviolet (UV) light on photosensitivity in patients with cutaneous LE, we designed immunopathologic in vitro and in vivo experiments to evaluate the effects of UV on the binding of such autoantibodies to the surface of human keratinocytes, one major target of immunologic damage in photosensitive LE. Short-term 2% paraformaldehyde fixation of suspensions of cultured human keratinocytes previously incubated with monospecific antiserum probes enabled the detection of ENA expression on the cell surfacemore » by flow-cytometry analysis. UVB light (280-320 nm) induced the binding of monospecific antibody probes for SS-A/Ro and SS-B/La on keratinocytes in a dose-dependent pattern with maximal induction observed at the dose of 200 mJ/cm2 UVB. Binding of SS-A/Ro, SS-B/La, and RNP antibody was augmented strongly, but binding of anti-Sm was very weak. In contrast, UVA (320-400 nm) light had no effect on the induction of binding of these antibody probes. Identical results were seen by standard immunofluorescence techniques. Hydroxyurea-treated keratinocytes showed similar induction of those antigens by UVB irradiation, which suggested that ENA expression on cultured keratinocytes by UVB were cell-cycle independent. Tunicamycin, an inhibitor of glycosylation of proteins, reduced UVB light effect on the SS-A/Ro and SS-B/La antigen's expression. These in vitro FACS analyses revealed that ENA augmentation on the keratinocyte cell surface was dose dependent, UVB dependent, glycosylation dependent, and cell-cycle independent. In vivo ENA augmentation on the keratinocyte surface was examined in suction blister epidermal roofs.« less

Promotion of plant growth by Pseudomonas fluorescens strain SS101 via novel volatile organic compounds.

PubMed

Park, Yong-Soon; Dutta, Swarnalee; Ann, Mina; Raaijmakers, Jos M; Park, Kyungseok

2015-05-29

Volatile organic compounds (VOCs) from plant growth-promoting rhizobacteria (PGPR) play key roles in modulating plant growth and induced systemic resistance (ISR) to pathogens. Despite their significance, the physiological functions of the specific VOCs produced by Pseudomonas fluorescens SS101 (Pf.SS101) have not been precisely elucidated. The effects of Pf.SS101 and its VOCs on augmentation of plant growth promotion were investigated in vitro and in planta. A significant growth promotion was observed in plants exposed Pf.SS101 under both conditions, suggesting that its VOCs play a key role in promoting plant growth. Solid-phase micro-extraction (SPME) and a gas chromatography-mass spectrophotometer (GC-MS) system were used to characterize the VOCs emitted by Pf.SS101 and 11 different compounds were detected in samples inoculated this bacterium, including 13-Tetradecadien-1-ol, 2-butanone and 2-Methyl-n-1-tridecene. Application of these compounds resulted in enhanced plant growth. This study suggests that Pf.SS101 promotes the growth of plants via the release of VOCs including 13-Tetradecadien-1-ol, 2-butanone and 2-Methyl-n-1-tridecene, thus increasing understanding of the role of VOCs in plant-bacterial inter-communication. Copyright © 2015 Elsevier Inc. All rights reserved.

Characterization of 316L(N)-IG SS joint produced by hot isostatic pressing technique

NASA Astrophysics Data System (ADS)

Nakano, J.; Miwa, Y.; Tsukada, T.; Kikuchi, M.; Kita, S.; Nemoto, Y.; Tsuji, H.; Jitsukawa, S.

2002-12-01

Type 316L(N) stainless steel of the international thermonuclear experimental reactor grade (316L(N)-IG SS) is being considered for the first wall/blanket module. Hot isostatic pressing (HIP) technique is expected for the fabrication of the module. To evaluate the integrity and susceptibility to stress corrosion cracking (SCC) of HIPed 316L(N)-IG SS, tensile tests in vacuum and slow strain rate tests in high temperature water were performed. Specimen with the HIPed joint had similar tensile properties to specimens of 316L(N)-IG SS, and did not show susceptibility to SCC in oxygenated water at 423 K. Thermally sensitized specimen was low susceptible to SCC even in the creviced condition. It is concluded that the tensile properties of HIPed SS are as high as those of the base alloy and the HIP process caused no deleterious effects.

Strong circumstantial proofs about the intermediate polar nature of the cataclysmic variable SS Cygni

NASA Astrophysics Data System (ADS)

Giovannelli, Franco; Sabau-Graziati, Lola

This paper is the updated version of that published in the proceedings of the Integral/Bart Workshop 2011 (Giovannelli & Sabau-Graziati, 2012a). SS Cyg is a cataclysmic variable usually classified as dwarf nova, a subclass of the non-magnetic cataclysmic variables. The goal of this paper is to demonstrate -- on the basis of the many arguments and circumstantial proofs derived from the numerous multifrequency data obtained from the SS Cyg binary system -- that such classification is wrong and that the intermediate polar nature of SS Cyg is the most probable. We derive the magnetic field intensity at the surface of the white dwarf in SS Cyg as B ≃ 1.6 ± 0.7 MG. This value is in complete agreement with the evaluation made by Fabbiano et al. (1981) (B< 1.9 MG) using simultaneous X-ray, UV, and optical data.

The N-terminal Part of Arabidopsis thaliana Starch Synthase 4 Determines the Localization and Activity of the Enzyme.

PubMed

Raynaud, Sandy; Ragel, Paula; Rojas, Tomás; Mérida, Ángel

2016-05-13

Starch synthase 4 (SS4) plays a specific role in starch synthesis because it controls the number of starch granules synthesized in the chloroplast and is involved in the initiation of the starch granule. We showed previously that SS4 interacts with fibrillins 1 and is associated with plastoglobules, suborganelle compartments physically attached to the thylakoid membrane in chloroplasts. Both SS4 localization and its interaction with fibrillins 1 were mediated by the N-terminal part of SS4. Here we show that the coiled-coil region within the N-terminal portion of SS4 is involved in both processes. Elimination of this region prevents SS4 from binding to fibrillins 1 and alters SS4 localization in the chloroplast. We also show that SS4 forms dimers, which depends on a region located between the coiled-coil region and the glycosyltransferase domain of SS4. This region is highly conserved between all SS4 enzymes sequenced to date. We show that the dimerization seems to be necessary for the activity of the enzyme. Both dimerization and the functionality of the coiled-coil region are conserved among SS4 proteins from phylogenetically distant species, such as Arabidopsis and Brachypodium This finding suggests that the mechanism of action of SS4 is conserved among different plant species. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Production of Angiotensin-I-Converting-Enzyme-Inhibitory Peptides in Fermented Milks Started by Lactobacillus delbrueckii subsp. bulgaricus SS1 and Lactococcus lactis subsp. cremoris FT4

PubMed Central

Gobbetti, M.; Ferranti, P.; Smacchi, E.; Goffredi, F.; Addeo, F.

2000-01-01

Two fermented milks containing angiotensin-I-converting-enzyme (ACE)-inhibitory peptides were produced by using selected Lactobacillus delbrueckii subsp. bulgaricus SS1 and L. lactis subsp. cremoris FT4. The pH 4.6-soluble nitrogen fraction of the two fermented milks was fractionated by reversed-phase fast-protein liquid chromatography. The fractions which showed the highest ACE-inhibitory indexes were further purified, and the related peptides were sequenced by tandem fast atom bombardment-mass spectrometry. The most inhibitory fractions of the milk fermented by L. delbrueckii subsp. bulgaricus SS1 contained the sequences of β-casein (β-CN) fragment 6-14 (f6-14), f7-14, f73-82, f74-82, and f75-82. Those from the milk fermented by L. lactis subsp. cremoris FT4 contained the sequences of β-CN f7-14, f47-52, and f169-175 and κ-CN f155-160 and f152-160. Most of these sequences had features in common with other ACE-inhibitory peptides reported in the literature. In particular, the β-CN f47-52 sequence had high homology with that of angiotensin-II. Some of these peptides were chemically synthesized. The 50% inhibitory concentrations (IC50s) of the crude purified fractions containing the peptide mixture were very low (8.0 to 11.2 mg/liter). When the synthesized peptides were used individually, the ACE-inhibitory activity was confirmed but the IC50s increased considerably. A strengthened inhibitory effect of the peptide mixtures with respect to the activity of individual peptides was presumed. Once generated, the inhibitory peptides were resistant to further proteolysis either during dairy processing or by trypsin and chymotrypsin. PMID:10966406

Fast Ss-Ilm a Computationally Efficient Algorithm to Discover Socially Important Locations

NASA Astrophysics Data System (ADS)

Dokuz, A. S.; Celik, M.

2017-11-01

Socially important locations are places which are frequently visited by social media users in their social media lifetime. Discovering socially important locations provide several valuable information about user behaviours on social media networking sites. However, discovering socially important locations are challenging due to data volume and dimensions, spatial and temporal calculations, location sparseness in social media datasets, and inefficiency of current algorithms. In the literature, several studies are conducted to discover important locations, however, the proposed approaches do not work in computationally efficient manner. In this study, we propose Fast SS-ILM algorithm by modifying the algorithm of SS-ILM to mine socially important locations efficiently. Experimental results show that proposed Fast SS-ILM algorithm decreases execution time of socially important locations discovery process up to 20 %.

Combinatorial gene editing in mammalian cells using ssODNs and TALENs

NASA Astrophysics Data System (ADS)

Strouse, Bryan; Bialk, Pawel; Niamat, Rohina A.; Rivera-Torres, Natalia; Kmiec, Eric B.

2014-01-01

The regulation of gene editing is being elucidated in mammalian cells and its potential as well as its limitations are becoming evident. ssODNs carry out gene editing by annealing to their complimentary sequence at the target site and acting as primers for replication fork extension. To effect a genetic change, a large amount of ssODN molecules must be introduced into cells and as such induce a Reduced Proliferation Phenotype (RPP), a phenomenon in which corrected cells do not proliferate. To overcome this limitation, we have used TAL-Effector Nucleases (TALENs) to increase the frequency, while reducing the amount of ssODN required to direct gene correction. This strategy resolves the problem and averts the serious effects of RPP. The efficiency of gene editing can be increased significantly if cells are targeted while they progress through S phase. Our studies define new reaction parameters that will help guide experimental strategies of gene editing.

SWIFT Observations of a Far UV Luminosity Component in SS433

NASA Technical Reports Server (NTRS)

Cannizzo, J. K.; Boyd, P. T.; Dolan, J. F.

2007-01-01

SS433 is a binary system showing relativistic Doppler shifts in its two sets of emission lines. The origin of its UV continuum is not well established. We observed SS433 to determine the emission mechanism responsible for its far UV spectrum. The source was observed at several different phases of both its 13 d orbital period and 162.5 d precession period using the UVOT and XRT detector systems on Swift. The far UV spectrum down to 1880 Angstrom lies significantly above the spectral flux distribution predicted by extrapolating the reddened blackbody continuum that fits the spectrum above 3500 Angstroms. The intensity of the far UV flux varies over a period of days and the variability is correlated with the variability of the soft X-ray flux from the source. An emission mechanism in addition to those previously detected in the optical and X-ray regions must exist in the far UV spectrum of SS433.

Protein dynamics during presynaptic complex assembly on individual ssDNA molecules

PubMed Central

Gibb, Bryan; Ye, Ling F.; Kwon, YoungHo; Niu, Hengyao; Sung, Patrick; Greene, Eric C.

2014-01-01

Homologous recombination is a conserved pathway for repairing double–stranded breaks, which are processed to yield single–stranded DNA overhangs that serve as platforms for presynaptic complex assembly. Here we use single–molecule imaging to reveal the interplay between Saccharomyce cerevisiae RPA, Rad52, and Rad51 during presynaptic complex assembly. We show that Rad52 binds RPA–ssDNA and suppresses RPA turnover, highlighting an unanticipated regulatory influence on protein dynamics. Rad51 binding extends the ssDNA, and Rad52–RPA clusters remain interspersed along the presynaptic complex. These clusters promote additional binding of RPA and Rad52. Together, our work illustrates the spatial and temporal progression of RPA and Rad52 association with the presynaptic complex, and reveals a novel RPA–Rad52–Rad51–ssDNA intermediate, which has implications for understanding how the activities of Rad52 and RPA are coordinated with Rad51 during the later stages recombination. PMID:25195049

alpha(4)beta(7) independent pathway for CD8(+) T cell-mediated intestinal immunity to rotavirus.

PubMed

Kuklin, N A; Rott, L; Darling, J; Campbell, J J; Franco, M; Feng, N; Müller, W; Wagner, N; Altman, J; Butcher, E C; Greenberg, H B

2000-12-01

Rotavirus (RV), which replicates exclusively in cells of the small intestine, is the most important cause of severe diarrhea in young children worldwide. Using a mouse model, we show that expression of the intestinal homing integrin alpha(4)ss(7) is not essential for CD8(+) T cells to migrate to the intestine or provide immunity to RV. Mice deficient in ss7 expression (ss7(-/-)) and unable to express alpha(4)ss(7) integrin were found to clear RV as quickly as wild-type (wt) animals. Depletion of CD8(+) T cells in ss7(-/-) animals prolonged viral shedding, and transfer of immune ss7(-/-) CD8(+) T cells into chronically infected Rag-2-deficient mice resolved RV infection as efficiently as wt CD8(+) T cells. Paradoxically, alpha(4)ss(7)(hi) memory CD8(+) T cells purified from wt mice that had been orally immunized cleared RV more efficiently than alpha(4)ss(7)(low) CD8(+) T cells. We explained this apparent contradiction by demonstrating that expression of alpha(4)ss(7) on effector CD8(+) T cells depends upon the site of initial antigen exposure: oral immunization generates RV-specific CD8(+) T cells primarily of an alpha(4)ss(7)(hi) phenotype, but subcutaneous immunization yields both alpha(4)ss(7)(hi) and alpha(4)ss(7)(low) immune CD8(+) T cells with anti-RV effector capabilities. Thus, alpha(4)ss(7) facilitates normal intestinal immune trafficking to the gut, but it is not required for effective CD8(+) T cell immunity.

The structural characterization of some biomaterials, type AISI 310, used in medicine

NASA Astrophysics Data System (ADS)

Minciuna, M. G.; Vizureanu, P.; Hanganu, C.; Achitei, D. C.; Popescu, D. C.; Focsaneanu, S. C.

2016-06-01

Orthopedics biomaterials are intended for implantation in the human body and substituted or help to repair of bones, cartilage or organ transplant, and tendons. At the end of the 20th century, the availability of materials for the manufacture implants used in medicine has been the same as for other industrial applications. The most used metals for manufacturing the orthopedics implants are: stainless steels, cobalt-chrome-molybdenum alloys, titanium and his alloys. The structural researches which are made in this paper, offer a complete analysis of AISI310 stainless steels, using: optical spectrometry, X-ray diffraction and scanning electronic microscopy.

Intra-instar larval cannibalism in Anopheles gambiae (s.s.) and Anopheles stephensi (Diptera: Culicidae).

PubMed

Porretta, Daniele; Mastrantonio, Valentina; Crasta, Graziano; Bellini, Romeo; Comandatore, Francesco; Rossi, Paolo; Favia, Guido; Bandi, Claudio; Urbanelli, Sandra

2016-11-02

Cannibalism has been observed in a wide range of animal taxa and its importance in persistence and stability of populations has been documented. In anopheline malaria vectors the inter-instar cannibalism between fourth- and first-instar larvae (L4-L1) has been shown in several species, while intra-instar cannibalism remains poorly investigated. In this study we tested the occurrence of intra-instar cannibalism within larvae of second-, third- and fourth-instar (L2, L3 and L4) of Anopheles gambiae (s.s.) and An. stephensi. Experiments were set up under laboratory conditions and the effects of larval density, duration of the contact period among larvae and the presence of an older larva (i.e. a potential cannibal of bigger size) on cannibalism rate were analysed. Cannibalism was assessed by computing the number of missing larvae after 24 and 48 h from the beginning of the experiments and further documented by records with a GoPro videocamera. Intra-instar cannibalism was observed in all larval instars of both species with higher frequency in An. gambiae (s.s.) than in An. stephensi. In both species the total number of cannibalistic events increased from 0-24 to 0-48 h. The density affected the cannibalism rate, but its effect was related to the larval instar and to the presence of older larvae. Interestingly, the lower cannibalism rate between L4 larvae was observed at the highest density and the cannibalism rate between L3 larvae decreased when one L4 was added. The present study provides experimental evidence of intra-instar cannibalism in the malaria vectors An. gambiae (s.s.) and An. stephensi and highlights the possible occurrence of complex interactions between all larval instars potentially present in the breeding sites. We hypothesize that the high density and the presence of a potential cannibal of bigger size could affect the readiness to attack conspecifics, resulting into low risk larval behavior and lower cannibalism rate. The understanding of

Wear and corrosion resistance of laser-cladded Fe-based composite coatings on AISI 4130 steel

NASA Astrophysics Data System (ADS)

Fan, Li; Chen, Hai-yan; Dong, Yao-hua; Dong, Li-hua; Yin, Yan-sheng

2018-06-01

The wear and corrosion resistance of Fe72.2Cr16.8Ni7.3Mo1.6Mn0.7C0.2Si1.2 and Fe77.3Cr15.8Ni3.9Mo1.1Mn0.5C0.2Si1.2 coatings laser-cladded on AISI 4130 steel were studied. The coatings possess excellent wear and corrosion resistance despite the absence of expensive yttrium, tungsten, and cobalt and very little molybdenum. The microstructure mainly consists of dendrites and eutectic phases, such as duplex (γ+α)-Fe and the Fe-Cr (Ni) solid solution, confirmed via energy dispersive spectrometry and X-ray diffraction. The cladded Fe-based coatings have lower coefficients of friction, and narrower and shallower wear tracks than the substrate without the cladding, and the main wear mechanism is mild abrasive wear. Electrochemical test results suggest that the soft Fe72.2Cr16.8Ni7.3Mo1.6Mn0.7C0.2Si1.2 coating with high Cr and Ni concentrations has high passivation resistance, low corrosion current, and positive corrosion potential, providing a better protective barrier layer to the AISI 4130 steel against corrosion.

Effects of processing on the transverse fatigue properties of low-sulfur AISI 4140 steel

NASA Astrophysics Data System (ADS)

Collins, Sunniva R.; Michal, Gary M.

1993-12-01

The effects of inclusions due to steelmaking processes on the fatigue life of AISI 4140 have been investigated. The test matrix consisted of three commercially produced heats of AISI 4140 of comparable cleanliness: one was conventionally cast (CC), and two were inert gas-shielded/ bottom-poured (IGS). One of the IGS heats was calcium-treated to explore the effects of inclusion shape control (IGS/SC). All heats were hot-rolled and reduced over 95 pct to produce bar stock of 127 to 152 mm (5 to 6 in.) in diameter. Transverse axial specimens conforming to ASTM E466 were machined, quenched, and tempered to approximately 40 HRC, and they were fatigue tested in tension-tension cycling ( R = 0.1). Test results and statistical analyses of the stress-life data show that the IGS grade has several times the fatigue strength of the CC grade at 107 cycles. Lower-limit fatigue strengths calculated at a 99.9 pct probability were 518.5 MPa (75.2 ksi) for IGS vs 55.6 MPa (8.1 ksi) for the CC grade. The IGS/SC grade had the best performance at all stress and life levels. The results obtained indicate that fatigue performance can be improved by choosing a processing method that reduces the incidence of exogenous oxides and by controlling the shape of the sulfides.

Supramolecular order following binding of the dichroic birefringent sulfonic dye Ponceau SS to collagen fibers.

PubMed

Vidal, B C; Mello, M L S

2005-06-15

The optical anisotropies (linear dichroism or LD and birefringence) of crystalline aggregates of the sulfonic azo-dye Ponceau SS and of dye complexed with chicken tendon collagen fibers were investigated in order to assess their polarizing properties and similarity to liquid crystals. In some experiments, the staining was preceded by treatment with picric acid. Crystalline fibrous aggregates of the dye had a negative LD, and their electronic transitions were oriented perpendicular to the filamentary structures. The binding of Ponceau SS molecules to the collagen fibers altered the LD signal, with variations in the fiber orientation affecting the resulting dichroic ratios. The long axis of the rod-like dye molecule was assumed to be bound in register, parallel to the collagen fiber. Picric acid did not affect the oriented binding of the azo dye to collagen fibers. There were differences in the optical anisotropy of Ponceau SS-stained tendons from 21-day-old and 41-day-old chickens, indicating that Ponceau SS was able to distinguish between different ordered states of macromolecular aggregation in chicken tendon collagen fibers. In the presence of dichroic rod-like azo-dye molecules such as Ponceau SS, collagen also formed structures with a much higher degree of orientation. The presence of LD in the Ponceau SS-collagen complex even in unpolarized light indicated that this complex can act as a polarizer. Copyright 2005 Wiley Periodicals, Inc.

MIX and match: mobile T6SS MIX-effectors enhance bacterial fitness

PubMed Central

Salomon, Dor

2016-01-01

ABSTRACT Protein secretion systems that mediate interbacterial competition secret a wide repertoire of antibacterial toxins. A major player in these competitions is the newly discovered bacterial type VI secretion system (T6SS). We recently found that a subset of polymorphic MIX-effectors, which are a widespread class of effectors secreted by T6SSs, are horizontally shared between marine bacteria and are used to diversify their T6SS effector repertoires, thus enhancing their environmental fitness. In this commentary, I expand on the ideas that were introduced in the previous report, and further speculate on the possible mobility of other MIX-effectors. In addition, I discuss the possible role of horizontal gene transfer in the dissemination of MIX-effectors through bacterial genomes, as well as its possible role in diversifying the T6SS effector repertoire. PMID:27066305

KiSS-1 and reproduction: focus on its role in the metabolic regulation of fertility.

PubMed

Tena-Sempere, Manuel

2006-01-01

Unraveling of the master role of kisspeptins, the products of the KiSS-1 gene, and their receptor, GPR54, in the control of reproduction has been a major breakthrough in contemporary neuroendocrinology. Indeed, since the disclosure of their reproductive dimension in late 2003, an ever-growing number of genetic, molecular, physiologic and pharmacological studies have defined the crucial role of KiSS-1 neurons as central processors for the dynamic regulation of the gonadotropic axis and its full activation at puberty. Yet, the potential role of the hypothalamic KiSS-1 system as an intermediary factor for the well-known interplay between energy status and reproduction initially received little attention. Recent data, however, strongly suggest a prominent role of KiSS-1 in the metabolic control of fertility, as expression of KiSS-1 gene at the hypothalamus is down-regulated in conditions of negative energy balance and kisspeptin administration is capable of overcoming the hypogonadotropic state observed in undernutrition and disturbed metabolic conditions. Leptin, the adipocyte hormone signaling the size of body energy stores, is likely to play a pivotal role in the metabolic control of the KiSS-1 system, since kisspeptin neurons express leptin receptors and leptin is able to normalize defective KiSS-1 gene expression in models of impaired gonadotropin secretion linked to hypoleptinemia, such as the ob/ob mouse and streptozotocin-induced diabetic rat. In sum, these data provide strong evidence for a central role of kisspeptins and GPR54 as molecular conduits for the metabolic regulation of reproductive function - a phenomenon with potential physiopathologic and therapeutic implications.

Dahl SS rats demonstrate enhanced aortic perivascular adipose tissue-mediated buffering of vasoconstriction through activation of NOS in the endothelium

PubMed Central

Spradley, Frank T.; Ho, Dao H.

2015-01-01

Perivascular adipose tissue (PVAT) mediates buffering of vasoconstriction through activation of endothelium-derived factors. We hypothesized that the PVAT of Dahl salt-sensitive (Dahl SS) rats has reduced ability to buffer vasoconstriction. Vascular reactivity experiments were performed on aortic rings with PVAT intact (+PVAT) or removed (−PVAT), and endothelium intact (+ENDO) or removed (−ENDO) from Dahl SS rats and control SS.13BN rats (Dahl SS rats that have had chromosome 13 completely replaced with that of the Brown Norway rat, rendering this strain insensitive to high-salt or high-fat diet-induced hypertension). Endothelial dysfunction, assessed by ACh-mediated vasorelaxation, was confirmed in aortic rings of Dahl SS rats. The +PVAT+ENDO aortic rings had indistinguishable phenylephrine-induced vasoconstriction between genotypes. In both strains, removal of PVAT significantly enhanced vasoconstriction. Dahl SS rat −PVAT+ENDO aortic rings displayed exaggerated vasoconstriction to phenylephrine vs. SS.13BN rats, indicating that PVAT-mediated buffering of vasoconstriction was greater in Dahl SS rats. Removal of both the ENDO and PVAT restored vasoconstriction in both strains. The nitric oxide synthase (NOS) inhibitor, Nω-nitro-l-arginine methyl ester (l-NAME), produced a similar effect as that seen with −ENDO. These data indicate that the function of the PVAT to activate endothelium-derived NOS is enhanced in Dahl SS compared with SS.13BN rats and, most likely, occurs through a pathway that is distinct from ACh-mediated activation of NOS. PVAT weight and total PVAT leptin levels were greater in Dahl SS rats. Leptin induced a significantly decreased vasoconstriction in −PVAT+ENDO aortic rings from Dahl SS rats, but not SS.13BN rats. In contrast to our initial hypothesis, PVAT in Dahl SS rats buffers vasoconstriction by activating endothelial NOS via mechanisms that may include the involvement of leptin. Thus, the PVAT serves a vasoprotective role in

A novel, highly divergent ssDNA virus identified in Brazil infecting apple, pear and grapevine.

PubMed

Basso, Marcos Fernando; da Silva, José Cleydson Ferreira; Fajardo, Thor Vinícius Martins; Fontes, Elizabeth Pacheco Batista; Zerbini, Francisco Murilo

2015-12-02

Fruit trees of temperate and tropical climates are of great economical importance worldwide and several viruses have been reported affecting their productivity and longevity. Fruit trees of different Brazilian regions displaying virus-like symptoms were evaluated for infection by circular DNA viruses. Seventy-four fruit trees were sampled and a novel, highly divergent, monopartite circular ssDNA virus was cloned from apple, pear and grapevine trees. Forty-five complete viral genomes were sequenced, with a size of approx. 3.4 kb and organized into five ORFs. Deduced amino acid sequences showed identities in the range of 38% with unclassified circular ssDNA viruses, nanoviruses and alphasatellites (putative Replication-associated protein, Rep), and begomo-, curto- and mastreviruses (putative coat protein, CP, and movement protein, MP). A large intergenic region contains a short palindromic sequence capable of forming a hairpin-like structure with the loop sequence TAGTATTAC, identical to the conserved nonanucleotide of circoviruses, nanoviruses and alphasatellites. Recombination events were not detected and phylogenetic analysis showed a relationship with circo-, nano- and geminiviruses. PCR confirmed the presence of this novel ssDNA virus in field plants. Infectivity tests using the cloned viral genome confirmed its ability to infect apple and pear tree seedlings, but not Nicotiana benthamiana. The name "Temperate fruit decay-associated virus" (TFDaV) is proposed for this novel virus. Copyright © 2015 Elsevier B.V. All rights reserved.

Skipping Strategy (SS) for Initial Population of Job-Shop Scheduling Problem

NASA Astrophysics Data System (ADS)

Abdolrazzagh-Nezhad, M.; Nababan, E. B.; Sarim, H. M.

2018-03-01

Initial population in job-shop scheduling problem (JSSP) is an essential step to obtain near optimal solution. Techniques used to solve JSSP are computationally demanding. Skipping strategy (SS) is employed to acquire initial population after sequence of job on machine and sequence of operations (expressed in Plates-jobs and mPlates-jobs) are determined. The proposed technique is applied to benchmark datasets and the results are compared to that of other initialization techniques. It is shown that the initial population obtained from the SS approach could generate optimal solution.

NARSTO EPA SS LOS ANGELES PM25 NITRATE

Atmospheric Science Data Center

2018-04-09

NARSTO EPA SS LOS ANGELES PM25 NITRATE Project Title:  NARSTO Discipline:  ... Order:   E arthdata Search Parameters:  Nitrate Particles Order Data:  Earthdata Search:   Order ... Guide Documents:  Los Angeles PM25 Nitrate Guide Los Angeles Project Plan  (PDF) Los ...

The SS x-ray unit as an instrument for "total registration" and "race selection".

PubMed

Schmidt, Mathias; Winzen, Tina; Gross, Dominik

2015-05-01

The aim of this article is to show that, after the onset of World War II at the latest, the central task of the x-ray unit of the Nazi-SS (Schutzstaffel) led by Prof. Hans Holfelder was by no means the early diagnosis of tuberculosis. Its primary purpose, rather, was to serve the various "racial" and inhuman aims of the SS itself. Main historical sources and information about the SS x-ray unit are surveyed and analyzed. Clearly, the significance of the x-ray storm unit was increasingly subordinated to the necessities of the war until its original objectives disappeared from focus completely. The main purpose of operation of the x-ray storm unit thus by no means lay in the early detection of tuberculosis and did not therefore serve tuberculosis control. The actual objective lay, rather, in the implementation of SS aims in terms of Volk politics, genetics, and "racial hygiene".

Evidence of the Importance of Nox4 in Production of Hypertension in Dahl Salt-Sensitive Rats.

PubMed

Cowley, Allen W; Yang, Chun; Zheleznova, Nadezhda N; Staruschenko, Alexander; Kurth, Theresa; Rein, Lisa; Kumar, Vikash; Sadovnikov, Katherine; Dayton, Alex; Hoffman, Matthew; Ryan, Robert P; Skelton, Meredith M; Salehpour, Fahimeh; Ranji, Mahsa; Geurts, Aron

2016-02-01

This study reports the consequences of knocking out NADPH (nicotinamide adenine dinucleotide phosphate) oxidase 4 (Nox4) on the development of hypertension and kidney injury in the Dahl salt-sensitive (SS) rat. Zinc finger nuclease injection of single-cell SS embryos was used to create an 8 base-pair frame-shift deletion of Nox4, resulting in a loss of the ≈68 kDa band in Western blot analysis of renal cortical tissue of the knock out of Nox4 in the SS rat (SS(Nox4-/-)) rats. SS(Nox4-/-) rats exhibited a significant reduction of salt-induced hypertension compared with SS rats after 21 days of 4.0% NaCl diet (134±5 versus 151±3 mm Hg in SS) and a significant reduction of albuminuria, tubular casts, and glomerular injury. Optical fluorescence 3-dimensional cryoimaging revealed significantly higher redox ratios (NADH/FAD [reduced nicotinamide adenine dinucleotide/flavin adenine dinucleotide]) in the kidneys of SS(Nox4-/-) rats even when fed the 0.4% NaCl diet, indicating greater levels of mitochondrial electron transport chain metabolic activity and reduced oxidative stress compared with SS rats. Before the development of hypertension, RNA expression levels of Nox subunits Nox2, p67(phox), and p22(phox) were found to be significantly lower (P<0.05) in SS(Nox4-/-) compared with SS rats in the renal cortex. Thus, the mutation of Nox4 seems to modify transcription of several genes in ways that contribute to the protective effects observed in the SS(Nox4-/-) rats. We conclude that the reduced renal injury and attenuated blood pressure response to high salt in the SS(Nox4-/-) rat could be the result of multiple pathways, including gene transcription, mitochondrial energetics, oxidative stress, and protein matrix production impacted by the knock out of Nox4. © 2015 American Heart Association, Inc.

Immobilized and MgSO4 induced cost effective bacterial disintegration of waste activated sludge for effective anaerobic digestion.

PubMed

Ushani, U; Rajesh Banu, J; Kavitha, S; Kaliappan, S; Yeom, Ick Tae

2017-05-01

In this study, an attempt was made to disintegrate waste activated sludge (WAS) in a cost-effective way. During the first phase of this study, effective break down of extracellular polymeric substance (EPS) was performed by deflocculating WAS with 0.1 g/g SS of MgSO 4 . Deflocculation rate was 92% with discharge rate of extractable EPS at 185 mg/L. In the second phase, effective bacterial cell disintegration was obtained at 36 h post treatment. Maximum solubilization of deflocculated sludge was approximately 21%, which was higher than that of flocculated sludge (14.2%) or the control (4.5%). Biodegradability studies were assessed through kinetic analysis by non-linear regression modeling. Results revealed that the deflocculated sludge had higher methane generation (at about 235.8 mL/gVs) compared to flocculated sludge (at 146.1 mL/gVs) or the control (at 34.8 mL/gVs). Cost assessment of the present work revealed that the net yield for each ton of the deflocculated sludge was about 32.99 USD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Electron Backscatter Diffraction Analysis of Joints Between AISI 316L Austenitic/UNS S32750 Dual-Phase Stainless Steel

NASA Astrophysics Data System (ADS)

Shamanian, Morteza; Mohammadnezhad, Mahyar; Amini, Mahdi; Zabolian, Azam; Szpunar, Jerzy A.

2015-08-01

Stainless steels are among the most economical and highly practicable materials widely used in industrial areas due to their mechanical and corrosion resistances. In this study, a dissimilar weld joint consisting of an AISI 316L austenitic stainless steel (ASS) and a UNS S32750 dual-phase stainless steel was obtained under optimized welding conditions by gas tungsten arc welding technique using AWS A5.4:ER2594 filler metal. The effect of welding on the evolution of the microstructure, crystallographic texture, and micro-hardness distribution was also studied. The weld metal (WM) was found to be dual-phased; the microstructure is obtained by a fully ferritic solidification mode followed by austenite precipitation at both ferrite boundaries and ferrite grains through solid-state transformation. It is found that welding process can affect the ferrite content and grain growth phenomenon. The strong textures were found in the base metals for both steels. The AISI 316L ASS texture is composed of strong cube component. In the UNS S32750 dual-phase stainless steel, an important difference between the two phases can be seen in the texture evolution. Austenite phase is composed of a major cube component, whereas the ferrite texture mainly contains a major rotated cube component. The texture of the ferrite is stronger than that of austenite. In the WM, Kurdjumov-Sachs crystallographic orientation relationship is found in the solidification microstructure. The analysis of the Kernel average misorientation distribution shows that the residual strain is more concentrated in the austenite phase than in the other phase. The welding resulted in a significant hardness increase in the WM compared to initial ASS.

Degradation of Glucan Primers in the Absence of Starch Synthase 4 Disrupts Starch Granule Initiation in Arabidopsis*

PubMed Central

Lu, Kuan-Jen; Stettler, Michaela; Streb, Sebastian

2016-01-01

Arabidopsis leaf chloroplasts typically contain five to seven semicrystalline starch granules. It is not understood how the synthesis of each granule is initiated or how starch granule number is determined within each chloroplast. An Arabidopsis mutant lacking the glucosyl-transferase, STARCH SYNTHASE 4 (SS4) is impaired in its ability to initiate starch granules; its chloroplasts rarely contain more than one large granule, and the plants have a pale appearance and reduced growth. Here we report that the chloroplastic α-amylase AMY3, a starch-degrading enzyme, interferes with granule initiation in the ss4 mutant background. The amy3 single mutant is similar in phenotype to the wild type under normal growth conditions, with comparable numbers of starch granules per chloroplast. Interestingly, the ss4 mutant displays a pleiotropic reduction in the activity of AMY3. Remarkably, complete abolition of AMY3 (in the amy3 ss4 double mutant) increases the number of starch granules produced in each chloroplast, suppresses the pale phenotype of ss4, and nearly restores normal growth. The amy3 mutation also restores starch synthesis in the ss3 ss4 double mutant, which lacks STARCH SYNTHASE 3 (SS3) in addition to SS4. The ss3 ss4 line is unable to initiate any starch granules and is thus starchless. We suggest that SS4 plays a key role in granule initiation, allowing it to proceed in a way that avoids premature degradation of primers by starch hydrolases, such as AMY3. PMID:27458017

Studies on the determination of surface deuterium in AISI 1062, 4037, and 4140 steels by secondary ion mass spectrometry

NASA Astrophysics Data System (ADS)

Sastri, V. S.; Donepudi, V. S.; McIntyre, N. S.; Johnston, D.; Revie, R. W.

1988-12-01

The concentration of deuterium at the surface of cathodically charged high strength steels AISI 1062, 4037, and 4140 has been determined by secondary ion mass spectrometry (SIMS). The beneficial effects of pickling in NAP (a mixture of nitric, acetic, and phosphoric acids) to remove surfacebound deuterium have been observed.

Electrochemical studies on the performance of SS316L electrode in electrokinetics

NASA Astrophysics Data System (ADS)

Choi, Jeong-Hee; Maruthamuthu, Sundaram; Lee, Hyun-Goo; Ha, Tae-Hyun; Bae, Jeong-Hyo

2009-10-01

Organic and trace metal pollutants are removed by employing various electrodes in an electrokinetic (EK) process. Stainless steel was used either as an anode or a cathode by various investigators in electroremediation systems. In the present study, the role of SS316L as an anode and cathode in EK system was studied by the measurements of pH, conductivity of electrolyte, and potential of the anode and cathode at different current densities. The weight loss of the anode and cathode and the leaching of chromium, iron, and nickel at different current densities were measured and discussed with an electroosmosis process. The electrochemical behavior of SS316L electrode in neutral, acidic and alkaline pH in soil environment was studied by an electrochemical technique viz. polarization study. Surface analysis of SS316L after EK was done by XPS and SEM. The higher conductivity was noticed at anolyte when compared to catholyte. The weight loss of the anode was in the following order 0.615 > 0.307 > 0.123 mA/cm2 and the cathode corrosion rate was vice versa. Peroxide production was also noticed at the anolyte, which may encourage the degradation of the total organic content (TOC) in the soil. The OCP (open circuit potential) of SS316L was about +75 mV vs SCE in the soil extract; while adding acetic acid, the potential shifted to the positive side, to about +380 mV vs SCE. The breakdown potential and the range of passivation potential were higher in acetic acid added system when compared to other systems. Pitting was observed on both the anode and cathode within 48 h during the EK process. The present study concludes that SS is not a proper electrode material for the EK process.

Spectroscopic Observations of the Mass Donor Star in SS 433

NASA Astrophysics Data System (ADS)

Hillwig, T. C.; Gies, D. R.

2008-03-01

The microquasar SS 433 is an interacting massive binary consisting of an evolved mass donor and a compact companion that ejects relativistic jets. The mass donor was previously identified through spectroscopic observations of absorption lines in the blue part of the spectrum that showed Doppler shifts associated with orbital motion and strength variations related to the orbital modulation of the star-to-disk flux ratio and to disk obscuration. However, subsequent observations revealed other absorption features that lacked these properties and that were probably formed in the disk gas outflow. We present follow-up observations of SS 433 at orbital and precession phases identical to those from several previous studies, with the goals of confirming the detection of the mass donor spectrum and providing more reliable masses for the two system components. We show that the absorption features present as well as those previously observed almost certainly belong to the mass donor star, and find revised masses of 12.3 ± 3.3 and 4.3 ± 0.8 M⊙ for the mass donor and compact object, respectively. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (US), the Science and Technology Facilities Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and SECYT (Argentina).

X-ray variability of SS 433: Evidence for supercritical accretion

NASA Astrophysics Data System (ADS)

Atapin, K. E.; Fabrika, S. N.

2016-08-01

We study the X-ray variability of SS 433 based on data from the ASCA observatory and the MAXI and RXTE/ASM monitoring missions. Based on the ASCA data, we have constructed the power spectrum of SS 433 in the frequency range from 10-6 to 0.1 Hz, which confirms the presence of a flat portion in the spectrum at frequencies 3 × 10-5-10-3 Hz. The periodic variability (precession, nutation, eclipses) begins to dominate significantly over the stochastic variability at lower frequencies, which does not allow the stochastic variability to be studied reliably. The model in which the flat portion extends to 9.5 × 10-6 Hz, while a power-law rise with an index of 2.6 occurs below provides the best agreement with the observations. The nutational oscillations of the jets with a period of about three days suggests that the time for the passage of material through the disk is less than this value. At frequencies below 4 × 10-6 Hz, the shape of the power spectrum probably does not reflect the disk structure but is determined by external factors, for example, by a change in the amount of material supplied by the donor. The flat portion can arise from a rapid decrease in the viscous time in the supercritical or radiative disk zones. The flat spectrum is associated with the variability of the X-ray jets that are formed in the supercritical disk region.

HIV-Derived ssRNA Binds to TLR8 to Induce Inflammation-Driven Macrophage Foam Cell Formation

PubMed Central

Bernard, Mark A.; Han, Xinbing; Inderbitzin, Sonya; Agbim, Ifunanya; Zhao, Hui; Koziel, Henry; Tachado, Souvenir D.

2014-01-01

Even though combined anti-retroviral therapy (cART) dramatically improves patient survival, they remain at a higher risk of being afflicted with non-infectious complications such as cardiovascular disease (CVD). This increased risk is linked to persistent inflammation and chronic immune activation. In this study, we assessed whether this complication is related to HIV-derived ssRNAs inducing in macrophages increases in TNFα release through TLR8 activation leading to foam cell formation. HIV ssRNAs induced foam cell formation in monocyte-derived macrophages (MDMs) in a dose-dependent manner. This response was reduced when either endocytosis or endosomal acidification was inhibited by dynasore or chloroquine, respectively. Using a flow cytometry FRET assay, we demonstrated that ssRNAs bind to TLR8 in HEK cells. In MDMs, ssRNAs triggered a TLR8-mediated inflammatory response that ultimately lead to foam cell formation. Targeted silencing of the TLR8 and MYD88 genes reduced foam cell formation. Furthermore, foam cell formation induced by these ssRNAs was blocked by an anti-TNFα neutralizing antibody. Taken together in MDMs, HIV ssRNAs are internalized; bind TLR8 in the endosome followed by endosomal acidification. TLR8 signaling then triggers TNFα release and ultimately leads to foam cell formation. As this response was inhibited by a blocking anti-TNFα antibody, drug targeting HIV ssRNA-driven TLR8 activation may serve as a potential therapeutic target to reduce chronic immune activation and inflammation leading to CVD in HIV+ patients. PMID:25090652

Microstructural characterization of AA5183 aluminum clad AISI 1018 steel prepared by electro spark deposition

NASA Astrophysics Data System (ADS)

Rastkerdar, E.; Aghajani, H.; Kianvash, A.; Sorrell, C. C.

2018-04-01

The application of a simple and effective technique, electro spark deposition (ESD), to create aluminum clad steel plate has been studied. AA5183 aluminum rods were used as the rotating electrode for cladding of the AISI 1018 steel. The microstructure of the interfacial zone including the intermetallic compounds (IMC) layer and the clad metal have been investigated by scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM and STEM). According to the results sound aluminum clad with thickness up to 25–30 μm can be achieved. Very thin (<4 μm) IMC layer was formed at the Al/Fe interface and the structural (electron diffraction pattern) and chemical analysis (STEM) conducted by TEM confirmed that the layer is constituted of Fe rich phases, both implying a much improved mechanical properties. Investigation of the orientations of phases at the interfacial zone confirmed absence of any preferred orientation.

Multi-scale virtual view on the precessing jet SS433

NASA Astrophysics Data System (ADS)

Monceau-Baroux, R.; Porth, O.; Meliani, Z.; Keppens, R.

2014-07-01

Observations of SS433 infer how an X-ray binary gives rise to a corkscrew patterned relativistic jet. XRB SS433 is well known on a large range of scales for wich we realize 3D simulation and radio mappings. For our study we use relativistic hydrodynamic in special relativity using a relativistic effective polytropic index. We use parameters extracted from observations to impose thermodynamical conditions of the ISM and jet. We follow the kinetic and thermal energy content, of the various ISM and jet regions. Our simulation follows simultaneously the evolution of the population of electrons which are accelerated by the jet. The evolving spectrum of these electrons, together with an assumed equipartition between dynamic and magnetic pressure, gives input for estimating the radio emission from our simulation. Ray tracing according to a direction of sight then realizes radio mappings of our data. Single snapshots are realised to compare with VLA observation as in Roberts et al. 2008. A radio movie is realised to compare with the 41 days movie made with the VLBA instrument. Finaly a larger scale simulation explore the discrepancy of opening angle between 10 and 20 degree between the large scale observation of SS433 and its close in observation.

Simulation of Thermo-viscoplastic Behaviors for AISI 4140 Steel

NASA Astrophysics Data System (ADS)

Li, Hong-Bin; Feng, Yun-Li

2016-04-01

The thermo-viscoplastic behaviors of AISI 4140 steel are investigated over wide ranges of strain rate and deformation temperature by isothermal compression tests. Based on the experimental results, a unified viscoplastic constitutive model is proposed to describe the hot compressive deformation behaviors of the studied steel. In order to reasonably evaluate the work hardening behaviors, a strain hardening material constant (h0) is expressed as a function of deformation temperature and strain rate in the proposed constitutive model. Also, the sensitivity of initial value of internal variable s to the deformation temperature is discussed. Furthermore, it is found that the initial value of internal variable s can be expressed as a linear function of deformation temperature. Comparisons between the measured and predicted results confirm that the proposed constitutive model can give an accurate and precise estimate of the inelastic stress-strain relationships for the studied high-strength steel.

Estimation of Mechanical Properties of Stainless Steel AISI 410 by Small-Punch Testing (Erickson Test)

NASA Astrophysics Data System (ADS)

Hassan, A.-P.

2014-07-01

The small-punch testing (SPT) method is used for determining the mechanical properties of AISI 410 (0.14% C, 12% Cr) stainless steel. A thin disc-shaped specimen with known mechanical properties is pressed with a small ball until the appearance of cracks in the former. The load - displacement curves are recorded. Computation of the yield strength and fracture energy by the curve obtained and by known formulas shows good convergence with the characteristics obtained by standard testing.

Oxynitrides decorated 316L SS for potential bioimplant application

NASA Astrophysics Data System (ADS)

Saravanan Kaliaraj, Gobi; Kumar, N.

2018-03-01

Titanium oxynitride (TiON) and zirconium oxynitride (ZrON) were deposited onto 316L stainless steel (316L SS) using reactive magnetron sputtering technique. The monoclinic and cubic phase of TiON and ZrON were obtained by x-ray diffraction (XRD). Nanoindentation and wear test analysis exhibited the better mechanical properties of TiON and ZrON films. Wettability studies showed hydrophilic nature on coated films; whereas bare 316L SS substrate was least hydrophilic. Drastic reduction of bacterial adhesion (Pseudomonas aeruginosa), as well as biofilm formation, was observed in both the films at different time duration. TiON and ZrON films were exhibited excellent hemocompatibility by preventing the platelet activation. Furthermore, the coated films exhibited corrosion protection in presence and absence of hydrogen peroxide (H2O2) in artificial blood plasma (ABP) solution.

True logarithmic amplification of frequency clock in SS-OCT for calibration

PubMed Central

Liu, Bin; Azimi, Ehsan; Brezinski, Mark E.

2011-01-01

With swept source optical coherence tomography (SS-OCT), imprecise signal calibration prevents optimal imaging of biological tissues such as coronary artery. This work demonstrates an approach using a true logarithmic amplifier to precondition the clock signal, with the effort to minimize the noises and phase errors for optimal calibration. This method was validated and tested with a high-speed SS-OCT. The experimental results manifest its superior ability on optimization of the calibration and improvement of the imaging performance. Particularly, this hardware-based approach is suitable for real-time calibration in a high-speed system where computation time is constrained. PMID:21698036

Maternal predictive factors for fetal congenital heart block in pregnant mothers positive for anti-SS-A antibodies.

PubMed

Tsuboi, Hiroto; Sumida, Takayuki; Noma, Hisashi; Yamagishi, Kazumasa; Anami, Ai; Fukushima, Kotaro; Horigome, Hitoshi; Maeno, Yasuki; Kishimoto, Mitsumasa; Takasaki, Yoshinari; Nakayama, Masahiro; Waguri, Masako; Sago, Haruhiko; Murashima, Atsuko

2016-07-01

To determine the maternal predictive factors for fetal congenital heart block (CHB) in pregnancy in mothers positive for anti-SS-A antibodies. The Research Team for Surveillance of Autoantibody-Exposed Fetuses and Treatment of Neonatal Lupus Erythematosus, the Research Program of the Japan Ministry of Health, Labor and Welfare, performed a national survey on pregnancy of mothers positive for anti-SS-A antibodies. We analyzed 635 pregnant mothers who tested positive for anti-SS-A antibodies before conception but had no previous history of fetal CHB. We performed univariate and multivariate analysis (models 1, 2, and 3 using different set of independent variables) investigated the relation between risk of fetal CHB and maternal clinical features. Of the 635 pregnant mothers, fetal CHB was detected in 16. Univariate analysis showed that fetal CHB associated with use of corticosteroids before conception (OR 3.72, p = 0.04), and negatively with use of corticosteroids (equivalent doses of prednisolone (PSL), at ≥10 mg/day) after conception before 16-week gestation (OR 0.17, p = 0.03). In multivariate analysis, model 1 identified the use of corticosteroids before conception (OR 4.28, p = 0.04) and high titer of anti-SS-A antibodies (OR 3.58, p = 0.02) as independent and significant risk factors, and model 3 identified use of corticosteroids (equivalent doses of PSL, at ≥10 mg/day) after conception before 16-week gestation as independent protective factor against the development of fetal CHB (OR 0.16, p = 0.03). Other maternal clinical features did not influence the development of fetal CHB. The results identified high titers of anti-SS-A antibodies and use of corticosteroids before conception as independent risk factors, and use of corticosteroids (equivalent doses of PSL, at ≥10 mg/day) after conception before 16-week gestation as an independent protective factor for fetal CHB.

Microchemical and microstructural evolution of AISI 304 stainless steel irradiated in EBR-II at PWR-relevant dpa rates

NASA Astrophysics Data System (ADS)

Dong, Y.; Sencer, B. H.; Garner, F. A.; Marquis, E. A.

2015-12-01

AISI 304 stainless steel was irradiated at 416 °C and 450 °C at a 4.4 × 10-9 and 3.05 × 10-7 dpa/s to ∼0.4 and ∼28 dpa, respectively, in the reflector of the EBR-II fast reactor. Both unirradiated and irradiated conditions were examined using standard and scanning transmission electron microscopy, energy dispersive spectroscopy, and atom probe tomography on very small specimens produced by focused ion beam milling. These results are compared with previous electron microscopy examination of 3 mm disks from essentially the same material. By comparing a very low dose specimen with a much higher dose specimen, both derived from a single reactor assembly, it has been demonstrated that the coupled microstructural and microchemical evolution of dislocation loops and other sinks begins very early, with elemental segregation producing at these sinks what appears to be measurable precursors to fully formed precipitates found at higher doses. The nature of these sinks and their possible precursors are examined in detail.

Irradiation creep and swelling of AISI 316 to exposures of 130 dpa at 385?400$deg;C

NASA Astrophysics Data System (ADS)

Garner, F. A.; Porter, D. L.

1988-07-01

The creep and swelling of AISI 316 stainless steel have been studied at 385 to 400°C in EBR-II to doses of 130 dpa. Most creep capsules were operated at constant stress and temperature but mid-life changes in these variables were also made. This paper concentrates on the behavior of the 20% cold-worked condition but five other conditions were also studied. Swelling at ⩽ 400° C was found to lose the sensitivity to stress exhibited at higher temperatures while the creep rate was found to retain linear dependencies on both stress and swelling rate. The creep coefficients extracted at 400°C agree with those found in other experiments conducted at higher temperatures. In the temperature range of ⩽ 400° C, swelling is in the recombinationdominated regime and the swelling rate falls strongly away from the ~1%/dpa rate observed at higher temperatures. These lower rates of creep and swelling, coupled with the attainment of high damage levels without failure, encourage the use of AISI 316 in the construction of water-cooled fusion first walls operating at temperatures below 400°C.

Wear behavior of the surface alloyed AISI 1020 steel with Fe-Nb-B by TIG welding technique

NASA Astrophysics Data System (ADS)

Kilinc, B.; Durmaz, M.; Abakay, E.; Sen, U.; Sen, S.

2015-03-01

Weld overlay coatings also known as hardfacing is a method which involves melting of the alloys and solidification for applied coatings. Recently hardfacing by welding has become a commonly used technique for improvement of material performance in extreme (high temperature, impact/abrasion, erosion, etc.) conditions.In the present study, the coatings were produced from a mixture of ferrous niobium, ferrous boron and iron powders in the ranges of -45µm particle size with different ratio. Fe12Nb5B3 and Fe2NbBalloys were coated on the AISI 1020 steel surface by TIG welding. The phases formed in the coated layer are Fe2B, NbB2, NbFeB and Fe0,2 Nb0,8 phases. The hardness of the presence phases are changing between 1689±85 HV0.01, and 181±7 HV0.1. Microstructural examinations were realized by optical and scanning electron microscopy. The wear and friction behaviors of Fe12Nb5B3 and Fe2NbB realized on the AISI 1020 steel were investigated by the technique of TIG welding by using ball-on-disk arrangement against alumina ball.

Relativistic jets in SS 433

NASA Astrophysics Data System (ADS)

Margon, B.

1982-01-01

A variety of recent optical, radio, and X-ray observations have confirmed the hypothesis that the peculiar star SS 433 is ejecting two narrow, opposed, highly collimated jets of matter at one-quarter the speed of light. This unique behavior is probably driven by mass exchange between a relatively normal star and a compact companion, either a neutron star or a black hole. However, numerous details regarding the energetics, radiation, acceleration, and collimation of the jets remain to be understood. This phenomenon may well be a miniature example of similar collimated ejection of gas by active extragalactic objects such as quasars and radio galaxies.

[Mini-KiSS--a multimodal group therapy intervention for parents of young children with sleep disorders: a pilot study].

PubMed

Schlarb, Angelika Anita; Brandhorst, Isabel; Hautzinger, Martin

2011-05-01

Sleep disorders in early childhood tend to be chronic and almost always a burden for the parents. This study developed and evaluated a multimodal parent training program for children 0.5 to 4 years of age suffering from sleep disorders (Mini-KiSS). We hypothesized that there would be specific improvements following the structured group training (reduction of sleep problems, improvement of parental well-being). The pilot study consisted of a pre-post test design without control group. Participants were n = 17 parents of children 0.5 to 4 years of age with sleep disorders determined according to the ICSD-II. Each of the six sessions was evaluated, and changes were assessed by sleep diary and CBCL. Behavioral and emotional problems of the child were assessed by CBCL, parental well-being, and SCL-90-R. The results showed high acceptance of Mini-KiSS and satisfactory feasibility. Children showed significant improvements of the sleep disturbances such as nightly awakenings as well as sleeping in parents' bed. Furthermore, improvements were found for children's emotional and behavioral problems and for parental well-being, in particular for the depression scale of the mother. This pilot study shows a high acceptance and good feasibility of the multimodal short-time parent-training program Mini-KiSS. Sleep problems were significantly reduced.

Constituents of the Essential Oil of Suregada zanzibariensis Leaves are Repellent to the Mosquito, Anopheles gambiae s.s.

PubMed Central

Innocent, Ester; Joseph, Cosam C.; Gikonyo, Nicholas K.; Nkunya, Mayunga H.H.; Hassanali, Ahmed

2010-01-01

In traditional African communities, repellent volatiles from certain plants generated by direct burning or by thermal expulsion have played an important role in protecting households against vectors of malaria and other diseases. Previous research on volatile constituents of plants has shown that some are good sources of potent mosquito repellents. In this bioprospecting initiative, the essential oil of leaves of the tree, Suregada zanzibariensis Verdc. (Angiospermae: Euphobiaceae) was tested against the mosquito, Anopheles gambiae s.s. Giles (Diptera: Culicidae) and found to be repellent. Gas chromatography (GC), GC-linked mass spectrometry (GC-MS) and, where possible, GC-co-injections with authentic compounds, led to the identification of about 34 compounds in the essential oil. About 56% of the constituents were terpenoid ketones, mostly methyl ketones. Phenylacetaldehyde (14.4%), artemisia ketone (10.1%), (1S)-(-)-verbenone (12.1%) and geranyl acetone (9.4%) were the main constituents. Apart from phenylacetaldehyde, repellent activities of the other main constituents were higher than that of the essential oil. The blends of the main constituents in proportions found in the essential oil were more repellent to An. gambiae s.s. than was the parent oil (p < 0.05), and the presence of artemisia ketone in the blend caused a significant increase in the repellency of the resulting blend. These results suggested that blends of some terpenoid ketones can serve as effective An. gambiae s.s. mosquito repellents. PMID:20569134

Constituents of the essential oil of Suregada zanzibariensis leaves are repellent to the mosquito, Anopheles gambiae s.s.

PubMed

Innocent, Ester; Joseph, Cosam C; Gikonyo, Nicholas K; Nkunya, Mayunga H H; Hassanali, Ahmed

2010-01-01

In traditional African communities, repellent volatiles from certain plants generated by direct burning or by thermal expulsion have played an important role in protecting households against vectors of malaria and other diseases. Previous research on volatile constituents of plants has shown that some are good sources of potent mosquito repellents. In this bioprospecting initiative, the essential oil of leaves of the tree, Suregada zanzibariensis Verdc. (Angiospermae: Euphobiaceae) was tested against the mosquito, Anopheles gambiae s.s. Giles (Diptera: Culicidae) and found to be repellent. Gas chromatography (GC), GC-linked mass spectrometry (GC-MS) and, where possible, GC-co-injections with authentic compounds, led to the identification of about 34 compounds in the essential oil. About 56% of the constituents were terpenoid ketones, mostly methyl ketones. Phenylacetaldehyde (14.4%), artemisia ketone (10.1%), (1S)-(-)-verbenone (12.1%) and geranyl acetone (9.4%) were the main constituents. Apart from phenylacetaldehyde, repellent activities of the other main constituents were higher than that of the essential oil. The blends of the main constituents in proportions found in the essential oil were more repellent to An. gambiae s.s. than was the parent oil (p < 0.05), and the presence of artemisia ketone in the blend caused a significant increase in the repellency of the resulting blend. These results suggested that blends of some terpenoid ketones can serve as effective An. gambiae s.s. mosquito repellents.

Microstructural and Electrochemical Evaluation of Fusion Welded Low-Nickel and 304 SS at Different Heat Input

NASA Astrophysics Data System (ADS)

Bansod, Ankur V.; Patil, Awanikumar P.; Moon, Abhijeet P.; Shukla, Sourabh

2017-12-01

The present research study investigates the effect of heat input using E 308 electrode (controlled by welding current, i.e., 70, 85 and 100 A) on microstructure, mechanical properties and corrosion behavior of low-nickel and 304 stainless steel (SS) weldments produced by shielded metal arc welding technique. SEM investigation shows that with the higher heat input, δ-ferrite content was reduced. Dendrite and inter-dendritic length is also reduced by lowering the heat input. For all the heat inputs, it is observed that δ-ferrite content was higher in 304 stainless steel (SS) as compared to that of low-nickel austenitic stainless steel (Cr-Mn SS). Considering the heat input for Cr-Mn SS, coarse grains were observed in the heat-affected zone region. For low heat input (LHI), tensile fracture surface has exhibited river-like pattern with dimple appearance. Corrosion studies show better pitting resistance for low heat input (LHI) samples due to higher δ-ferrite present in the weld region. Similarly, higher interphase corrosion resistance is observed in both the SS grades causing more dissolution in the LHI samples.

PU/SS EUTECTIC ASSESSMENT IN 9975 PACKAGINGS IN A STORAGE FACILITY DURING EXTENDED FIRE

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

Gupta, N.

2012-03-26

In a radioactive material (RAM) packaging, the formation of eutectic at the Pu/SS (plutonium/stainless steel) interface is a serious concern and must be avoided to prevent of leakage of fissile material to the environment. The eutectic temperature for the Pu/SS is rather low (410 C) and could seriously impact the structural integrity of the containment vessel under accident conditions involving fire. The 9975 packaging is used for long term storage of Pu bearing materials in the DOE complex where the Pu comes in contact with the stainless steel containment vessel. Due to the serious consequences of the containment breach atmore » the eutectic site, the Pu/SS interface temperature is kept well below the eutectic formation temperature of 410 C. This paper discusses the thermal models and the results for the extended fire conditions (1500 F for 86 minutes) that exist in a long term storage facility and concludes that the 9975 packaging Pu/SS interface temperature is well below the eutectic temperature.« less

Tribological properties of CrN coatings deposited by nitro-chromizing treatment on AISI D2 steel

NASA Astrophysics Data System (ADS)

Durmaz, M.; Kilinc, B.; Abakay, E.; Sen, U.; Sen, S.

2015-03-01

In this work, the wear test of uncoated and chromium nitride coated AISI D2 cold work tool steel against alumina ball realized at 0.1 m/s sliding speeds and under the loads of 2.5N, 5N and 10N. Steel samples were nitrided at 575°C for 8 h in the first step of the coating process, and then chromium nitride coating was performed thermo-reactive deposition technique (TRD) in a powder mixture consisting of ferro-chromium, ammonium chloride and alumina at 1000°C for 2 h. Nitro-chromized samples were characterized by X-Ray diffraction analysis (XRD), scanning electron microscopy (SEM), micro-hardness and ball on disk wear tests. The coating layer formed on the AISI D2 steel was compact and homogeneous. X-ray studies showed that the phase formed in the coated layer is Cr2N. The depth of the layer was 8.15 µm. The average hardness of the layer was 2160±15 HV0.025. For uncoated and chromium nitride materials, wear rate increased with increasing load. The results of friction coefficient and wear rate of the tested materials showed that the CrN coating presents the lowest results.

Tribological properties of CrN coatings deposited by nitro-chromizing treatment on AISI D2 steel

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

Durmaz, M., E-mail: mdurmaz@sakarya.edu.tr; Abakay, E.; Sen, U.

2015-03-30

In this work, the wear test of uncoated and chromium nitride coated AISI D2 cold work tool steel against alumina ball realized at 0.1 m/s sliding speeds and under the loads of 2.5N, 5N and 10N. Steel samples were nitrided at 575°C for 8 h in the first step of the coating process, and then chromium nitride coating was performed thermo-reactive deposition technique (TRD) in a powder mixture consisting of ferro-chromium, ammonium chloride and alumina at 1000°C for 2 h. Nitro-chromized samples were characterized by X-Ray diffraction analysis (XRD), scanning electron microscopy (SEM), micro-hardness and ball on disk wear tests. The coating layermore » formed on the AISI D2 steel was compact and homogeneous. X-ray studies showed that the phase formed in the coated layer is Cr{sub 2}N. The depth of the layer was 8.15 µm. The average hardness of the layer was 2160±15 HV{sub 0.025}. For uncoated and chromium nitride materials, wear rate increased with increasing load. The results of friction coefficient and wear rate of the tested materials showed that the CrN coating presents the lowest results.« less

Micro-Abrasion Wear Resistance of Borided 316L Stainless Steel and AISI 1018 Steel

NASA Astrophysics Data System (ADS)

Reséndiz-Calderon, C. D.; Rodríguez-Castro, G. A.; Meneses-Amador, A.; Campos-Silva, I. E.; Andraca-Adame, J.; Palomar-Pardavé, M. E.; Gallardo-Hernández, E. A.

2017-11-01

The 316L stainless steel has high corrosion resistance but low tribological performance. In different industrial sectors (biomedical, chemical, petrochemical, and nuclear engineering), improvement upon wear resistance of 316L stainless steel components using accessible and inexpensive methods is critical. The AISI 1018 steel is widely used in industry, but its tribological performance is not the best among steels. Therefore, in this study the behavior of the borided 316L stainless steel and 1018 steel is evaluated under micro-abrasion wear. The boriding was carried out at 1223 K over 6 h of exposure time, resulting in a biphase layer composed of FeB/Fe2B phases. In order to evaluate Fe2B phase with no influence from FeB phase, AISI 1018 steel samples were borided at 1273 K for over 20 min and then diffusion annealed at 1273 K over 2 h to obtain a Fe2B mono-phase layer. Micro-abrasion wear resistance was evaluated by a commercial micro-abrasion testing rig using a mix of F-1200 SiC particles with deionized water as abrasive slurry. The obtained wear rates for FeB and Fe2B phases and for the 316L stainless steel were compared. Wear resistance of 316L stainless steel increases after boriding. The wear mechanisms for both phases and for the stainless steel were identified. Also, transient conditions for rolling and grooving abrasion were determined for the FeB and Fe2B phases.

On the origin of X-ray variability of SS 433

NASA Astrophysics Data System (ADS)

Band, D. L.; Grindlay, J. E.

1984-10-01

The X-ray flares observed from the central source in SS 433 by the Einstein telescope are attributed to surges in the mass transfer rate due to changes in the critical Roche volume of the companion. Analysis of the Roche potential for a primary with spin misaligned with the orbital axis, as required by the slaved disk model, predicts that the critical Roche volume will contract twice per orbit if the orbit is circular. A critical Roche volume fractional change of 1-2 percent is found by applying this potential to SS 433. The nutation of the companion should not affect the steady precession of its spin. Aspects of this work strengthen the evidence that the compact object might be a black hole.

Test launch of a Topol/SS-25 missile

NASA Image and Video Library

2013-10-10

View of test launch of a Topol/SS-25 missile on Oct. 10, 2013 as seen by the Expedition 37 crew aboard the International Space Station (ISS). The missile was launched at 17:39 MSK (13:39 UTC) from Kapustin Yar to the Sary Shagan test site in Kazakhstan. Also sent as Twitter message.

The role of the C-domain of bacteriophage T4 gene 32 protein in ssDNA binding and dsDNA helix-destabilization: Kinetic, single-molecule, and cross-linking studies

PubMed Central

Pant, Kiran; Anderson, Brian; Perdana, Hendrik; Malinowski, Matthew A.; Win, Aye T.; Williams, Mark C.

2018-01-01

The model single-stranded DNA binding protein of bacteriophage T4, gene 32 protein (gp32) has well-established roles in DNA replication, recombination, and repair. gp32 is a single-chain polypeptide consisting of three domains. Based on thermodynamics and kinetics measurements, we have proposed that gp32 can undergo a conformational change where the acidic C-terminal domain binds internally to or near the single-stranded (ss) DNA binding surface in the core (central) domain, blocking ssDNA interaction. To test this model, we have employed a variety of experimental approaches and gp32 variants to characterize this conformational change. Utilizing stopped-flow methods, the association kinetics of wild type and truncated forms of gp32 with ssDNA were measured. When the C-domain is present, the log-log plot of k vs. [NaCl] shows a positive slope, whereas when it is absent (*I protein), there is little rate change with salt concentration, as expected for this model.A gp32 variant lacking residues 292–296 within the C-domain, ΔPR201, displays kinetic properties intermediate between gp32 and *I. The single molecule force-induced DNA helix-destabilizing activitiesas well as the single- and double-stranded DNA affinities of ΔPR201 and gp32 truncated at residue 295 also fall between full-length protein and *I. Finally, chemical cross-linking of recombinant C-domain and gp32 lacking both N- and C-terminal domains is inhibited by increasing concentrations of a short single-stranded oligonucleotide, and the salt dependence of cross-linking mirrors that expected for the model. Taken together, these results provide the first evidence in support of this model that have been obtained through structural probes. PMID:29634784

HTV-4 approach

NASA Image and Video Library

2013-08-09

ISS036-E-030064 (9 Aug. 2013) --- The unpiloted Japanese "Kounotori" H2 Transfer Vehicle-4 (HTV-4) approaches the International Space Station. The HTV, a 33-foot-long, 13-foot-diameter unmanned cargo transfer spacecraft, is delivering 3.6 tons of science experiments, equipment and supplies to the orbiting complex. HTV-4 launched from the Tanegashima Space Center in southern Japan on Aug.3 at 3:48 p.m. (Aug. 4 at 4:48 a.m., Japan time).

HTV-4 approach

NASA Image and Video Library

2013-08-09

ISS036-E-029969 (9 Aug. 2013) --- The unpiloted Japanese "Kounotori" H2 Transfer Vehicle-4 (HTV-4) approaches the International Space Station. The HTV, a 33-foot-long, 13-foot-diameter unmanned cargo transfer spacecraft, is delivering 3.6 tons of science experiments, equipment and supplies to the orbiting complex. HTV-4 launched from the Tanegashima Space Center in southern Japan on Aug.3 at 3:48 p.m. (Aug. 4 at 4:48 a.m., Japan time).

HTV-4 approach

NASA Image and Video Library

2013-08-09

ISS036-E-029963 (9 Aug. 2013) --- The unpiloted Japanese "Kounotori" H2 Transfer Vehicle-4 (HTV-4) approaches the International Space Station. The HTV, a 33-foot-long, 13-foot-diameter unmanned cargo transfer spacecraft, is delivering 3.6 tons of science experiments, equipment and supplies to the orbiting complex. HTV-4 launched from the Tanegashima Space Center in southern Japan on Aug.3 at 3:48 p.m. (Aug. 4 at 4:48 a.m., Japan time).

HTV-4 approach

NASA Image and Video Library

2013-08-09

ISS036-E-030067 (9 Aug. 2013) --- The unpiloted Japanese "Kounotori" H2 Transfer Vehicle-4 (HTV-4) approaches the International Space Station. The HTV, a 33-foot-long, 13-foot-diameter unmanned cargo transfer spacecraft, is delivering 3.6 tons of science experiments, equipment and supplies to the orbiting complex. HTV-4 launched from the Tanegashima Space Center in southern Japan on Aug.3 at 3:48 p.m. (Aug. 4 at 4:48 a.m., Japan time).

Comparisons of modified Vasco X-2 and AISI 9310 gear steels

NASA Technical Reports Server (NTRS)

Townsend, D. P.; Zaretsky, E. V.

1980-01-01

Endurance tests were conducted with four groups of spur gears manufactured from three heats of consumable electrode vacuum melted (CVM) modified Vasco X-2. Endurance tests were also conducted with gears manufactured from CVM AISI 9310. Bench type rolling element fatigue tests were conducted with both materials. Hardness measurements were made to 811 K. There was no statistically significant life difference between the two materials. Life differences between the different heats of modified Vasco X-2 can be attributed to heat treat variation and resultant hardness. Carburization of gear flanks only can eliminate tooth fracture as a primary failure mode for modified Vasco X-2. However, a tooth surface fatigue spall can act as a nucleus of a tooth fracture failure for the modified Vasco X-2.

Effects of fresh gas flow, tidal volume, and charcoal filters on the washout of sevoflurane from the Datex Ohmeda (GE) Aisys, Aestiva/5, and Excel 210 SE Anesthesia Workstations.

PubMed

Sabouri, A Sassan; Lerman, Jerrold; Heard, Christopher

2014-10-01

We investigated the effects of tidal volume (VT), fresh gas flow (FGF), and a charcoal filter in the inspiratory limb on the washout of sevoflurane from the following Datex Ohmeda (GE) Anesthesia Workstations (AWSs): Aisys, Aestiva/5, and Excel 210SE. After equilibrating the AWSs with 2% sevoflurane, the anesthetic was discontinued, and the absorbent anesthesia breathing circuit (ABC), reservoir bag, and test lung were changed. The lung was ventilated with 350 or 200 mL·breath(-1), 15 breaths·min(-1), and a FGF of 10 L·min(-1) while the washout of sevoflurane was performed in triplicate using a calibrated Datex Ohmeda Capnomac Ultima™ and a calibrated MIRAN SapphIRe XL ambient air analyzer until the concentration was ≤ 10 parts per million (ppm). The effects of decreasing the FGF to 5 and 2 L·min(-1) after the initial washout and of a charcoal filter in the ABC were recorded separately. The median washout times with the Aisys AWS (14 min, P < 0.01) and the Aestiva/5 (17 min, P < 0.001) with VT 350 mL·breath(-1) were significantly less than that with the Excel 210SE (32 min). The mean (95% confidence interval) washout time with the Aisys increased to 23.5 (21.5 to 25.5) min with VT 200 mL·breath(-1) (P < 0.01). Decreasing the FGF from 10 to 5 and 2 L·min(-1) with the Aisys caused a rebound in sevoflurane concentration to ≥ 50 ppm. Placement of a charcoal filter in the inspiratory limb reduced the sevoflurane concentration to < 2 ppm in the Aisys and Aestiva/5 AWSs within two minutes. The GE AWSs should be purged with large FGFs and VTs ~350 mL·breath(-1) for ~25 min to achieve 10 ppm sevoflurane. The FGF should be maintained to avoid a rebound in anesthetic concentration. Charcoal filters rapidly decrease the anesthetic concentration to < 2 ppm.

ssDNA degradation along capillary electrophoresis process using a Tris buffer.

PubMed

Ric, Audrey; Ong-Meang, Varravaddheay; Poinsot, Verena; Martins-Froment, Nathalie; Chauvet, Fabien; Boutonnet, Audrey; Ginot, Frédéric; Ecochard, Vincent; Paquereau, Laurent; Couderc, François

2017-06-01

Tris-Acetate buffer is currently used in the selection and the characterization of ssDNA by capillary electrophoresis (CE). By applying high voltage, the migration of ionic species into the capillary generates a current that induces water electrolysis. This phenomenon is followed by the modification of the pH and the production of Tris derivatives. By injecting ten times by capillary electrophoresis ssDNA (50 nM), the whole oligonucleotide was degraded. In this paper, we will show that the Tris buffer in the running vials is modified along the electrophoretic process by electrochemical reactions. We also observed that the composition of the metal ions changes in the running buffer vials. This phenomenon, never described in CE, is important for fluorescent ssDNA analysis using Tris buffer. The oligonucleotides are degraded by electrochemically synthesized species (present in the running Tris vials) until it disappears, even if the separation buffer in the capillary is clean. To address these issues, we propose to use a sodium phosphate buffer that we demonstrate to be electrochemically inactive. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Guidelines for Design, Construction, and Evaluation of Airport Pavement Drainage

DTIC Science & Technology

1990-10-01

AISI for storm sewers (11). To prevent suspended matter from depositing in the pipes, it is important to maintain sufficient velocity within the pipes...IN FEET/DAY "KS 4090 1 4100 J:HS/DS 4110 ’ 4120 X=WS/DS 4130 ’ 4140 Yz(1-J)/X 4150 ’ 4160 ’OUTFLOW 4170 QS=Y*KS*SS A-6 4180 1 4190 PRINT "OUTFLOW TO

A Mutation in the Start Codon of γ-Crystallin D Leads to Nuclear Cataracts in the Dahl SS/Jr-Ctr Strain

PubMed Central

Johnson, Ashley C.; Lee, Jonathan W.; Harmon, Ashlyn C.; Morris, Zaliya; Wang, Xuexiang; Fratkin, Jonathan; Rapp, John P.; Gomez-Sanchez, Elise; Garrett, Michael R.

2013-01-01

Cataracts are a major cause of blindness. The most common forms of cataracts are age and UV related and develops mostly in the elderly, while congenital cataracts appear at birth or in early childhood. The Dahl salt-sensitive (SS/Jr) rat is an extensively used model of salt-sensitive hypertension that exhibits concomitant renal disease. In the mid 1980’s, cataracts appeared in a few animals in the Dahl S colony, presumably the result of a spontaneous mutation. The mutation was fixed and bred to establish the SS/Jr-Ctr substrain. The SS/Jr-Ctr substrain has been exclusively used by a single investigator to study the role of steroids and hypertension. Using a classical positional cloning approach, we localized the cataract gene with high-resolution to a less than 1 Mbp region on chromosome 9 using an F1 (SS/Jr-Ctr X SHR) X SHR backcross population. The 1 Mbp region contained only 13 genes, including 4 genes from the γ-crystallins (Cryg) gene family which are known to play a role in cataract formation. All of the γ-crystallins were sequenced and a novel point mutation in the start codon (ATG → GTG) of the Crygd gene was identified which led to the complete absence of CRYGD protein in the eyes of the SS/Jr-Ctr strain. In summary, the identification of the genetic cause in this novel cataract model may provide an opportunity to better understand the development of cataracts, particularly in the context of hypertension. PMID:23404175

A user's guide to the ssWavelets package

Treesearch

J.H. ​Gove

2017-01-01

ssWavelets is an R package that is meant to be used in conjunction with the sampSurf package (Gove, 2012) to perform wavelet decomposition on the results of a sampling surface simulation. In general, the wavelet filter decomposes the sampSurf simulation results by scale (distance), with each scale corresponding to a different level of the...

Scalable and reusable emulator for evaluating the performance of SS7 networks

NASA Astrophysics Data System (ADS)

Lazar, Aurel A.; Tseng, Kent H.; Lim, Koon Seng; Choe, Winston

1994-04-01

A scalable and reusable emulator was designed and implemented for studying the behavior of SS7 networks. The emulator design was largely based on public domain software. It was developed on top of an environment supported by PVM, the Parallel Virtual Machine, and managed by OSIMIS-the OSI Management Information Service platform. The emulator runs on top of a commercially available ATM LAN interconnecting engineering workstations. As a case study for evaluating the emulator, the behavior of the Singapore National SS7 Network under fault and unbalanced loading conditions was investigated.

Development of Ultra-Fine-Grained Structure in AISI 321 Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Tiamiyu, A. A.; Szpunar, J. A.; Odeshi, A. G.; Oguocha, I.; Eskandari, M.

2017-12-01

Ultra-fine-grained (UFG) structure was developed in AISI 321 austenitic stainless steel (ASS) using cryogenic rolling followed by annealing treatments at 923 K, 973 K, 1023 K, and 1073 K (650 °C, 700 °C, 750 °C, and 800 °C) for different lengths of time. The α'-martensite to γ-austenite reversion behavior and the associated texture development were analyzed in the cryo-rolled specimens after annealing. The activation energy, Q, required for the reversion of α'-martensite to γ-austenite in the steel was estimated to be 80 kJ mol-1. TiC precipitates and unreversed triple junction α'-martensite played major roles in the development of UFG structure through the Zener pinning of grain boundaries. The optimum annealing temperature and time for the development of UFG structure in the cryo-rolled AISI 321 steel are (a) 923 K (650 °C) for approximately 28800 seconds and (b) 1023 K (750 °C) for 600 seconds, with average grain sizes of 0.22 and 0.31 µm, respectively. Annealing at 1023 K (750 °C) is considered a better alternative since the volume fraction of precipitated carbides in specimens annealed at 1023 K (750 °C) are less than those annealed at 923 K (650 °C). More so, the energy consumption during prolonged annealing time to achieve an UFG structure at 923 K (650 °C) is higher due to low phase reversion rate. The hardness of the UFG specimens is 195 pct greater than that of the as-received steel. The higher volume fraction of TiC precipitates in the UFG structure may be an additional source of hardening. Micro and macrotexture analysis indicated {110}〈uvw〉 as the major texture component of the austenite grains in the UFG structure. Its intensity is stronger in the specimen annealed at low temperatures.

Corrosion behaviour of electropolished AISI 316L austenitic biomaterial in physiological solution

NASA Astrophysics Data System (ADS)

Zatkalíková, V.; Markovičová, L.; Škorvanová, M.

2017-11-01

Due to suitable mechanical properties, satisfactory corrosion resistance and relatively low cost, austenitic stainless steels are important biomaterials for manufacture of implants and various medical instruments and devices. Their corrosion properties and biocompatibility are significantly affected by protective passive surface film quality, which depends on used mechanical and chemical surface treatment. This article deals with corrosion resistance of AISI 316L stainless steel, which is the most widely used Cr-Ni-Mo austenitic biomaterial. Corrosion behaviour of five various surfaces (original, electropolished, three surfaces with combined treatment finished by electropolishing) is evaluated on the bases of cyclic potentiodynamic polarization tests performed in physiological solution at the temperature of 37± 0.5 °C.

Echinococcus granulosus sensu stricto (s.s.) from the critically endangered antelope Addax nasomaculatus in Tunisia.

PubMed

Boufana, Belgees; Saïd, Yousra; Dhibi, Mokhtar; Craig, Philip S; Lahmar, Samia

2015-12-01

Echinococcus granulosus sensu lato (s.l.) is a zoonotic disease highly endemic in Tunisia. Canids including stray and semi-stray dogs, jackals and foxes are known as definitive hosts and a wide range of ungulates have been shown to harbour the metacestode hydatid stage and may serve as intermediate hosts. Fertile hydatid cysts of Echinococcus equinus and E. granulosus sensu stricto (s.s.) were recently molecularly identified for the first time from Tunisian donkeys. E. granulosus (s.s.) was also identified from wild boars in Tunisia. Here we report the confirmation of hydatid cysts caused by E. granulosus (s.s.) in the critically endangered antelope, Addax nasomaculatus in Tunisia. DNA-based molecular analysis revealed that A.nasomaculatus was infected with E. granulosus (s.s.) which had a 100% identity with the main globally distributed E. granulosus (s.s.) (EgTu01) haplotype. Cysts of Taenia hydatigena (n=33) were also observed on the liver and in the body cavity. Due to their endangered status and their relatively small numbers, it is unlikely that hydatid infection of A. nasomaculatus will form a major contribution to the epidemiology and transmission of E. granulosus in Tunisia, but infection may result in pathology, morbidity and early mortality, and may still play a role in the perpetuation of the parasite in wildlife cycles. Copyright © 2015 Elsevier B.V. All rights reserved.

Surface Conditioning of Cardiovascular 316L Stainless Steel Stents: a Review

NASA Astrophysics Data System (ADS)

Navarro, Lucila; Luna, Julio; Rintoul, Ignacio

2017-07-01

Cardiovascular disease is the leading cause of death worldwide and 90% of coronary interventions consists in stenting procedures. Most of the implanted stents are made of AISI 316L stainless steel (SS). Excellent mechanical properties, biocompatibility, corrosion resistance, workability and statistically demonstrated medical efficiency are the reasons for the preference of 316L SS over any other material for stent manufacture. However, patients receiving 316L SS bare stents are reported with 15-20% of restenosis probability. The decrease of the restenosis probability is the driving force for a number of strategies for surface conditioning of 316L SS stents. This review reports the latest advances in coating, passivation and the generation of controlled topographies as strategies for increasing the corrosion resistance and reducing the ion release and restenosis probability on 316L SS stents. Undoubtedly, the future of technique is related to the elimination of interfaces with abrupt change of properties, the elimination of molecules and any other phase somehow linked to the metal substrate. And leaving the physical, chemical and topographical smart modification of the outer part of the 316L SS stent for enhancing the biocompatiblization with endothelial tissues.

Periodicity Analysis of X-ray Light Curves of SS 433

NASA Astrophysics Data System (ADS)

Wang, J. Y.; Lu, X. L.; Zhao, Q. W.; Dong, D. Q.; Lao, B. Q.; Lu, Y.; Wei, Y. H.; Wu, X. C.; An, T.

2016-03-01

SS 433 is the only X-ray binary to date that was detected to have a pair of well-collimated jets, and its orbital period, super orbital period, and nutation period were all detected at the same time. The study on the periodic X-ray variabilities is helpful for understanding its dynamic process of the central engine and the correlation with other bands. In the present paper, two time series analysis techniques, Lomb-Scargle periodogram and weighted wavelet Z-transform, are employed to search for the periodicities from the Swift/BAT (Burst Alert Telescope)(15--50 keV) and RXTE/ASM (Rossi X-Ray Timing Explorer/All-Sky Monitor)(1.5--3, 3--5 and 5--12 keV) light curves of SS 433, and the Monte Carlo simulation is performed. For the 15--50 keV energy band, five significant periodic signals are detected, which are P_1(˜6.29 d), P_2 (˜6.54 d), P_3 (˜13.08 d), P_4 (˜81.50 d), and P_5 (˜162.30 d). For the 3--5 and 5--12 keV energy bands, periodic signals P_3 (˜13 d) and P_5 (˜162 d) are detected in both energy bands. However, for the 1.5--3 keV energy band, no significant periodic signal is detected. P_5 has the strongest periodic signal in the power spectrum for all the energy bands of 3--5, 5--12, and 15--50 keV, and it is consistent with that obtained by previous study in optical band. Further, due to the existence of relativistic radio jets, the X-ray and optical band variability of P_5 (˜162 d) is probably related to the precession of the relativistic jets. High coherence between X-ray and optical light curves may also imply that the X-ray and optical emissions are of the same physical origin. P_3 shows a good agreement with the orbital period (˜13.07 d) first obtained by previous study, and P_2 and P_4 are the high frequency harmonic components of P_3 and P_5, respectively. P_1 is detected from the power spectrum of 15--50 keV energy band only, and it is consistent with the systematic nutation period. As the power of energy band decreases (from hard X-ray to

Experimental and numerical study on plasma nitriding of AISI P20 mold steel

NASA Astrophysics Data System (ADS)

Nayebpashaee, N.; Vafaeenezhad, H.; Kheirandish, Sh.; Soltanieh, M.

2016-09-01

In this study, plasma nitriding was used to fabricate a hard protective layer on AISI P20 steel, at three process temperatures (450°C, 500°C, and 550°C) and over a range of time periods (2.5, 5, 7.5, and 10 h), and at a fixed gas N2:H2 ratio of 75vol%:25vol%. The morphology of samples was studied using optical microscopy and scanning electron microscopy, and the formed phase of each sample was determined by X-ray diffraction. The elemental depth profile was measured by energy dispersive X-ray spectroscopy, wavelength dispersive spectroscopy, and glow dispersive spectroscopy. The hardness profile of the samples was identified, and the microhardness profile from the surface to the sample center was recorded. The results show that ɛ-nitride is the dominant species after carrying out plasma nitriding in all strategies and that the plasma nitriding process improves the hardness up to more than three times. It is found that as the time and temperature of the process increase, the hardness and hardness depth of the diffusion zone considerably increase. Furthermore, artificial neural networks were used to predict the effects of operational parameters on the mechanical properties of plastic mold steel. The plasma temperature, running time of imposition, and target distance to the sample surface were all used as network inputs; Vickers hardness measurements were given as the output of the model. The model accurately reproduced the experimental outcomes under different operational conditions; therefore, it can be used in the effective simulation of the plasma nitriding process in AISI P20 steel.

Peripheral vascular response to mild indirect cooling in patients with homozygous sickle cell (SS) disease and the frequency of painful crisis.

PubMed

Mohan, J; Marshall, J M; Reid, H L; Thomas, P W; Hambleton, I; Serjeant, G R

1998-02-01

1. In homozygous sickle cell (SS) disease, skin cooling is a common precipitating factor of the painful crisis which is associated with avascular necrosis of active bone marrow. Since skin cooling does not directly induce sickling, we have investigated the nature of the reflex vascular responses to mild cooling in SS patients in a steady state of the disease and compared them with their history of painful crises. 2. Experiments were performed in Jamaica on 60 male SS patients and 30 matched control subjects with normal haemoglobin (AA) genotype. Forearm blood flow (FBF) was measured by venous occlusion plethysmography and mean arterial pressure (MAP) by a Finapres device: forearm vascular resistance (FVR) was calculated as MAP/FBF. Cutaneous erythrocyte flux in forearm and hand was monitored by a laser Doppler meter. The contralateral hand was immersed in cool water at 16 degrees C for 2 min, 6 times, at random intervals of 0.5-3 min. 3. The first cool immersion evoked an increase in MAP, cutaneous vasoconstriction and a net increase in FVR in both AA and SS subjects. However, the direction of change in FVR varied between individuals such that 18 AA subjects showed an increase in FVR (constrictor group) while 12 showed a decrease in FVR, indicating vasodilatation in forearm muscle (dilator group). In contrast, 50 SS subjects showed an increase in FVR and only 10 showed a decrease in FVR. The proportion of subjects who showed net vasoconstriction was significantly greater in the SS than in the AA group (83% versus 60%, P = 0.03, chi 2 test). 4. By the sixth cool stimulus, the 'dilator' group of AA subjects showed no change in FVR while the 'dilator' group of SS patients showed an increase in FVR. We suggest that forearm muscle vasodilatation was the characteristic component of the alerting/defence response to novel or noxious stimuli which habituates on repetition. 5. In the whole group of SS patients, baseline values of cutaneous vascular resistance and FVR

Simulation of kinematics of SS 433 radio jets that interact with the ambient medium

NASA Astrophysics Data System (ADS)

Panferov, A.

2014-02-01

Context. The mildly relativistic jets of SS 433 are believed to inflate the surrounding supernova remnant W 50, possibly depositing more than 99% of their kinetic energy in the remnant expansion. Where and how this transformation of the energy occurs is as yet unknown. We can learn from this that the jets decelerate and that this deceleration is non-dissipative. Aims: We uncover the deviation of the arcsecond-scale precessing radio jets of SS 433 from the ballistic locus described by the kinematic model as a signature of the dynamics issuing from the interaction of the jets with the ambient medium. Methods: To do this, we simulated the kinematics of these jets, taking into account the ram pressure on the jets, which we estimated from the profile of brightness of synchrotron radiation along the radio jets, assuming pressure balance in the jets. Results: We found that to fit an observable locus in all scales the radio jets need to be decelerated and twisted in addition to the precession torsion, mostly within the first one-fifth of the precession period, and subsequently they extend in a way that imitates ballistic jets. This jet kinematics implies a smaller distance to SS 433 than the currently accepted 5.5 kpc. The physical parameters of the jet model, which links jets dynamics with radiation, are physically reliable and characteristic for the SS 433 jets. The model proposes that beyond the radio-brightening zone, the jet clouds expand because they are in pressure balance with the intercloud medium, and heat up with distance according to the law T = 2 × 104(r/1015 cm)1.5 K. Conclusions: This model naturally explains and agrees with, the observed properties of the radio jets: a) the shock-pressed morphology; b) the brightness profile; c) the ~10% deflections of the jet kinematics from the standard kinematic model - a magnitude of the jet speed decrement in our simulation; d) the precession-phase deviations from the standard kinematic model predictions; e) the

Parsec-scale Variations in the 7Li I/6Li I Isotope Ratio Toward IC 348 and the Perseus OB 2 Association

NASA Astrophysics Data System (ADS)

Knauth, D. C.; Taylor, C. J.; Ritchey, A. M.; Federman, S. R.; Lambert, D. L.

2017-01-01

Measurements of the lithium isotopic ratio in the diffuse interstellar medium from high-resolution spectra of the Li I λ6708 resonance doublet have now been reported for a number of lines of sight. The majority of the results for the 7Li/6Li ratio are similar to the solar system ratio of 12.2, but the line of sight toward o Per, a star near the star-forming region IC 348, gave a ratio of about two, the expected value for gas exposed to spallation and fusion reactions driven by cosmic rays. To examine the association of IC 348 with cosmic rays more closely, we measured the lithium isotopic ratio for lines of sight to three stars within a few parsecs of o Per. One star, HD 281159, has 7Li/6Li ≃ 2 confirming production by cosmic rays. The lithium isotopic ratio toward o Per and HD 281159 together with published analyses of the chemistry of interstellar diatomic molecules suggest that the superbubble surrounding IC 348 is the source of the cosmic rays. Based on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen.

Wear behavior of the surface alloyed AISI 1020 steel with Fe-Nb-B by TIG welding technique

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

Kilinc, B., E-mail: bkilinc@sakarya.edu.tr; Durmaz, M.; Abakay, E.

Weld overlay coatings also known as hardfacing is a method which involves melting of the alloys and solidification for applied coatings. Recently hardfacing by welding has become a commonly used technique for improvement of material performance in extreme (high temperature, impact/abrasion, erosion, etc.) conditions.In the present study, the coatings were produced from a mixture of ferrous niobium, ferrous boron and iron powders in the ranges of -45µm particle size with different ratio. Fe{sub 12}Nb{sub 5}B{sub 3} and Fe{sub 2}NbBalloys were coated on the AISI 1020 steel surface by TIG welding. The phases formed in the coated layer are Fe{sub 2}B,more » NbB{sub 2}, NbFeB and Fe0,2 Nb{sub 0,8} phases. The hardness of the presence phases are changing between 1689±85 HV{sub 0.01}, and 181±7 HV{sub 0.1}. Microstructural examinations were realized by optical and scanning electron microscopy. The wear and friction behaviors of Fe{sub 12}Nb{sub 5}B{sub 3} and Fe2NbB realized on the AISI 1020 steel were investigated by the technique of TIG welding by using ball-on-disk arrangement against alumina ball.« less

Establishment and proteomic characterization of a novel synovial sarcoma cell line, NCC-SS2-C1.

PubMed

Oyama, Rieko; Kito, Fusako; Sakumoto, Marimu; Shiozawa, Kumiko; Toki, Shunichi; Endo, Makoto; Yoshida, Akihiko; Kawai, Akira; Kondo, Tadashi

2018-05-01

Synovial sarcoma is an aggressive mesenchymal tumor, characterized by the presence of unique transfusion gene, SS18-SSX. Cell lines enable researchers to investigate the molecular backgrounds of disease and the significance of SS18-SSX in relevant cellular contexts. We report the establishment and proteomic characterization of a novel synovial sarcoma cell line. Primary tissue culture was performed using tumor tissue of synovial sarcoma. The established cell line was authenticated by assessing its DNA microsatellite short tandem repeat analysis and characterized by in vitro assay. Proteomic study was achieved by mass spectrometry, and the results were analyzed by treemap. The cell line NCC-SS2-C1 was established from a primary tumor tissue of a synovial sarcoma patient. The cell line has grown well for 11 mo and has been subcultured more than 15 times. The established cells were authenticated by assessing their short tandem repeat pattern comparing with that of original tumor tissue. The cells showed polygonal in shape and formed spheroid when seeded on the low-attachment dish. Proteomic analysis revealed the molecular pathways which are unique to the original tumor tissue or the established cell line. In conclusion, a novel synovial sarcoma cell line NCC-SS2-C1 was successfully established from the primary tumor tissue. The cell line has characteristic transfusion SS18-SSX and poses aggressive in vitro growth and capability of spheroid formation. Thus, NCC-SS2-C1 cell line will be a useful tool for investigation of the mechanisms of disease and the biological role of fusion gene.

iSS-PseDNC: identifying splicing sites using pseudo dinucleotide composition.

PubMed

Chen, Wei; Feng, Peng-Mian; Lin, Hao; Chou, Kuo-Chen

2014-01-01

In eukaryotic genes, exons are generally interrupted by introns. Accurately removing introns and joining exons together are essential processes in eukaryotic gene expression. With the avalanche of genome sequences generated in the postgenomic age, it is highly desired to develop automated methods for rapid and effective detection of splice sites that play important roles in gene structure annotation and even in RNA splicing. Although a series of computational methods were proposed for splice site identification, most of them neglected the intrinsic local structural properties. In the present study, a predictor called "iSS-PseDNC" was developed for identifying splice sites. In the new predictor, the sequences were formulated by a novel feature-vector called "pseudo dinucleotide composition" (PseDNC) into which six DNA local structural properties were incorporated. It was observed by the rigorous cross-validation tests on two benchmark datasets that the overall success rates achieved by iSS-PseDNC in identifying splice donor site and splice acceptor site were 85.45% and 87.73%, respectively. It is anticipated that iSS-PseDNC may become a useful tool for identifying splice sites and that the six DNA local structural properties described in this paper may provide novel insights for in-depth investigations into the mechanism of RNA splicing.

Modelling of Tool Wear and Residual Stress during Machining of AISI H13 Tool Steel

NASA Astrophysics Data System (ADS)

Outeiro, José C.; Umbrello, Domenico; Pina, José C.; Rizzuti, Stefania

2007-05-01

Residual stresses can enhance or impair the ability of a component to withstand loading conditions in service (fatigue, creep, stress corrosion cracking, etc.), depending on their nature: compressive or tensile, respectively. This poses enormous problems in structural assembly as this affects the structural integrity of the whole part. In addition, tool wear issues are of critical importance in manufacturing since these affect component quality, tool life and machining cost. Therefore, prediction and control of both tool wear and the residual stresses in machining are absolutely necessary. In this work, a two-dimensional Finite Element model using an implicit Lagrangian formulation with an automatic remeshing was applied to simulate the orthogonal cutting process of AISI H13 tool steel. To validate such model the predicted and experimentally measured chip geometry, cutting forces, temperatures, tool wear and residual stresses on the machined affected layers were compared. The proposed FE model allowed us to investigate the influence of tool geometry, cutting regime parameters and tool wear on residual stress distribution in the machined surface and subsurface of AISI H13 tool steel. The obtained results permit to conclude that in order to reduce the magnitude of surface residual stresses, the cutting speed should be increased, the uncut chip thickness (or feed) should be reduced and machining with honed tools having large cutting edge radii produce better results than chamfered tools. Moreover, increasing tool wear increases the magnitude of surface residual stresses.

32 CFR Appendix E to Part 246 - Stars and Stripes (S&S) Board of Directors

Code of Federal Regulations, 2010 CFR

2010-07-01

... from the American Forces Information Service (AFIS) and one S&S may attend the meetings of the other S... DoD policy, the Unified Commands shall ask the Director of the AFIS for resolution. The S&S commander... Unified Commands shall forward the on-going strategic and corporate plan to the Director of the AFIS for...

32 CFR Appendix E to Part 246 - Stars and Stripes (S&S) Board of Directors

Code of Federal Regulations, 2011 CFR

2011-07-01

... from the American Forces Information Service (AFIS) and one S&S may attend the meetings of the other S... DoD policy, the Unified Commands shall ask the Director of the AFIS for resolution. The S&S commander... Unified Commands shall forward the on-going strategic and corporate plan to the Director of the AFIS for...

Study of Carbide Evolution During Thermo-Mechanical Processing of AISI D2 Tool Steel

NASA Astrophysics Data System (ADS)

Bombac, D.; Fazarinc, M.; Podder, A. Saha; Kugler, G.

2013-03-01

The microstructure of a cold-worked tool steel (AISI D2) with various thermo-mechanical treatments was examined in the current study to identify the effects of these treatments on phases. X-ray diffraction was used to identify phases. Microstructural changes such as spheroidization and coarsening of carbides were studied. Thermodynamic calculations were used to verify the results of the differential thermal analysis. It was found that soaking temperature and time have a large influence on dissolution, precipitation, spheroidization, and coalescence of carbides present in the steel. This consequently influences the hot workability and final properties.

Lead (Pb) bioaccumulation; genera Bacillus isolate S1 and SS19 as a case study

NASA Astrophysics Data System (ADS)

Arifiyanto, Achmad; Apriyanti, Fitria Dwi; Purwaningsih, Puput; Kalqutny, Septian Hary; Agustina, Dyah; Surtiningsih, Tini; Shovitri, Maya; Zulaika, Enny

2017-06-01

Lead (Pb) includes a group of large heavy metal in nature was toxic either on animal or human and did not provide an advantage function biologically. Bacillus isolates S1 and SS19 known resistant to lead up to 50 mg / L PbCl2. In this research will be examined whether genera Bacillus isolates S1 and SS19 could accumulate metal lead (Pb), their capability in accumulating and profile protein differences when the bacteria genera Bacillus isolates S1 and SS19 get exposed metal lead (Pb). Inoculum at age ± 9 hours are used, with a Nutrient Broth (NB) containing 50, 75 and 100 mg / L PbCl2. Inductively Coupled Plasma Atomic Emission Spectrometry (ICP) used to assessed Pb2+ concentrations. Bioaccumulation levels of Pb2+ by Bacillus isolate S1 and SS19 related to the distinction of beginning concentration to the final concentration. Bacillus isolate S1 achieved 53% and 51% bioaccumulation efficiency rate in lead presence concentration (75 and 100 mg/L) and 51% (50 mg/L). Another way Bacillus isolate SS19 was able to accumulate 57% (50 mg/L PbCl2) and kept stable on 36% bioaccumulation efficiency rate (75 and 100 mg/L PbCl2). Regarding SDS-PAGE electrophoresis protein profile result, protein in ± 127 kDa, molecule mass detected in the presence of Lead for Bacillus isolate S1.

NARSTO EPA SS NEW YORK AIR CHEM PM MET DATA

Atmospheric Science Data Center

2018-04-09

NARSTO EPA SS NEW YORK AIR CHEM PM MET DATA Project Title:  NARSTO ... Nitrogen Oxides Ozone Surface Winds Air Temperature Humidity Solar Irradiance Particulate Matter ... Data Guide Documents:  New York Air Chem Guide CPM Summary Report  (PDF) Nitrate ...

Design selection of an innovative tool holder for ultrasonic vibration assisted turning (IN-UVAT) using finite element analysis simulation

NASA Astrophysics Data System (ADS)

Rachmat, Haris; Ibrahim, M. Rasidi; Hasan, Sulaiman bin

2017-04-01

On of high technology in machining is ultrasonic vibration assisted turning. The design of tool holder was a crucial step to make sure the tool holder is enough to handle all forces on turning process. Because of the direct experimental approach is expensive, the paper studied to predict feasibility of tool holder displacement and effective stress was used the computational in finite element simulation. SS201 and AISI 1045 materials were used with sharp and ramp corners flexure hinges on design. The result shows that AISI 1045 material and which has ramp corner flexure hinge was the best choice to be produced. The displacement is around 11.3 micron and effective stress is 1.71e+008 N/m2 and also the factor of safety is 3.10.

Redox-sensitive micelles assembled from amphiphilic mPEG-PCL-SS-DTX conjugates for the delivery of docetaxel.

PubMed

Zhang, Huiyuan; Wang, Kaiming; Zhang, Pei; He, Wenxiu; Song, Aixin; Luan, Yuxia

2016-06-01

Docetaxel (DTX) can produce anti-tumor effects by inhibiting cell growth and inducing apoptosis. However, the poor solubility of DTX restricts its application and its clinical formulation has caused serious adverse reaction due to the use of Tween-80. In the present study, DTX was conjugated to an amphiphilic di-block polymer to solve these problems. Methoxy poly(ethylene glycol)-poly(ε-caprolactone) (mPEG-PCL) was selected as the polymer skeleton and a redox sensitive disulfide bond was used as the linker between DTX and mPEG-PCL. The synthesized mPEG-PCL-SS-DTX conjugates were characterized by (1)H-nuclear magnetic resonance ((1)H NMR) and Fourier transform infrared spectroscopy (FTIR). Interestingly, the mPEG-PCL-SS-DTX conjugates could self-assemble into micelles in aqueous solution. The critical micelle concentration (CMC) of mPEG-PCL-SS-DTX micelles was about 2.3mgL(-1) determined using pyrene molecule fluorescent probe method while the size of mPEG-PCL-SS-DTX micelles was determined to be ca. 17.6nm and 116.0nm with a bimodal distribution by dynamic light scattering (DLS). The in vitro release results indicated that the as-prepared micelles exhibited a sustained release profile with good redox sensitive properties. In particular, the hemolytic toxicity test indicated the as-prepared mPEG-PCL-SS-DTX micelles had negligible hemolytic activity, demonstrating their safety in drug delivery system. Cytotoxicity assay of the mPEG-PCL-SS-DTX micelles verified their highly enhanced cytotoxicity to MCF-7/A and A549 cells. These results thus demonstrated that the present redox-sensitive mPEG-PCL-SS-DTX micelle was an efficient and safe sustained drug delivery system in the biomedical area. Copyright © 2016 Elsevier B.V. All rights reserved.

Impaired myogenic response and autoregulation of cerebral blood flow is rescued in CYP4A1 transgenic Dahl salt-sensitive rat

PubMed Central

Fan, Fan; Geurts, Aron M.; Murphy, Sydney R.; Pabbidi, Mallikarjuna R.; Jacob, Howard J.

2014-01-01

We have reported that a reduction in renal production of 20-HETE contributes to development of hypertension in Dahl salt-sensitive (SS) rats. The present study examined whether 20-HETE production is also reduced in the cerebral vasculature of SS rats and whether this impairs the myogenic response and autoregulation of cerebral blood flow (CBF). The production of 20-HETE, the myogenic response of middle cerebral arteries (MCA), and autoregulation of CBF were compared in SS, SS-5BN rats and a newly generated CYP4A1 transgenic rat. 20-HETE production was 6-fold higher in cerebral arteries of CYP4A1 and SS-5BN than in SS rats. The diameter of the MCA decreased to 70 ± 3% to 65 ± 6% in CYP4A1 and SS-5BN rats when pressure was increased from 40 to 140 mmHg. In contrast, the myogenic response of MCA isolated from SS rats did not constrict. Administration of a 20-HETE synthesis inhibitor, HET0016, abolished the myogenic response of MCA in CYP4A1 and SS-5BN rats but had no effect in SS rats. Autoregulation of CBF was impaired in SS rats compared with CYP4A1 and SS-5BN rats. Blood-brain barrier leakage was 5-fold higher in the brain of SS rats than in SS-5BN and SS.CYP4A1 rats. These findings indicate that a genetic deficiency in the formation of 20-HETE contributes to an impaired myogenic response in MCA and autoregulation of CBF in SS rats and this may contribute to vascular remodeling and cerebral injury following the onset of hypertension. PMID:25540098

Upper Mantle Discontinuity Structure Beneath the Western Atlantic Ocean and Eastern North America from SS Precursors

NASA Astrophysics Data System (ADS)

Schmerr, N. C.; Beghein, C.; Kostic, D.; Baldridge, A. M.; West, J. D.; Nittler, L. R.; Bull, A. L.; Montesi, L.; Byrne, P. K.; Hummer, D. R.; Plescia, J. B.; Elkins-Tanton, L. T.; Lekic, V.; Schmidt, B. E.; Elkins, L. J.; Cooper, C. M.; ten Kate, I. L.; Van Hinsbergen, D. J. J.; Parai, R.; Glass, J. B.; Ni, J.; Fuji, N.; McCubbin, F. M.; Michalski, J. R.; Zhao, C.; Arevalo, R. D., Jr.; Koelemeijer, P.; Courtier, A. M.; Dalton, H.; Waszek, L.; Bahamonde, J.; Schmerr, B.; Gilpin, N.; Rosenshein, E.; Mach, K.; Ostrach, L. R.; Caracas, R.; Craddock, R. A.; Moore-Driskell, M. M.; Du Frane, W. L.; Kellogg, L. H.

2015-12-01

Seismic discontinuities within the mantle arise from a wide range of mechanisms, including changes in mineralogy, major element composition, melt content, volatile abundance, anisotropy, or a combination of the above. In particular, the depth and sharpness of upper mantle discontinuities at 410 and 660 km depth are attributed to solid-state phase changes sensitive to both mantle temperature and composition, where regions of thermal heterogeneity produce topography and chemical heterogeneity changes the impedance contrast across the discontinuity. Seismic mapping of this topography and sharpness thus provides constraint on the thermal and compositional state of the mantle. The EarthScope USArray is providing unprecedented access to a wide variety of new regions previously undersampled by the SS precursors. This includes the boundary between the oceanic plate in the western Atlantic Ocean and continental margin of eastern North America. Here we use a seismic array approach to image the depth, sharpness, and topography of the upper mantle discontinuities, as well as other possible upper mantle reflectors beneath this region. This array approach utilizes seismic waves that reflect off the underside of a mantle discontinuity and arrive several hundred seconds prior to the SS seismic phase as precursory energy. In this study, we collected high-quality broadband data SS precursors data from shallow focus (< 30 km deep), mid-Atlantic ridge earthquakes recorded by USArray seismometers in Alaska. We generated 4th root vespagrams to enhance the SS precursors and determine how they sample the mantle. Our data show detection of localized structure on the discontinuity boundaries as well as additional horizons, such as the X-discontinuity and a potential reflection from a discontinuity near the depth of the lithosphere-asthenosphere boundary. These structures are related to the transition from predominantly old ocean lithosphere to underlying continental lithosphere, as while

Xylanase production by a newly isolated Aspergillus niger SS7 in submerged culture.

PubMed

Bakri, Yasser; Al-Jazairi, Manal; Al-Kayat, Ghassan

2008-01-01

Xylanase production by a newly isolated Aspergillus niger SS7 was studied in submerged culture. The optimum initial pH for xylanase production was found to be 7.0. Different agricultural and industrial wastes were evaluated for their ability to induce xylanase production by this isolate. The best xylanase production (293.82 IU/ml) was recorded at 3% (w/v) corn cob hulls after 120 h of incubation. The Aspergillus niger SS7 isolate grown in a simple medium, proved to be a promising microorganism for xylanase production.

Spatiotemporal regulation of a Legionella pneumophila T4SS substrate by the metaeffector SidJ.

PubMed

Jeong, Kwang Cheol; Sexton, Jessica A; Vogel, Joseph P

2015-03-01

Modulation of host cell function is vital for intracellular pathogens to survive and replicate within host cells. Most commonly, these pathogens utilize specialized secretion systems to inject substrates (also called effector proteins) that function as toxins within host cells. Since it would be detrimental for an intracellular pathogen to immediately kill its host cell, it is essential that secreted toxins be inactivated or degraded after they have served their purpose. The pathogen Legionella pneumophila represents an ideal system to study interactions between toxins as it survives within host cells for approximately a day and its Dot/Icm type IVB secretion system (T4SS) injects a vast number of toxins. Previously we reported that the Dot/Icm substrates SidE, SdeA, SdeB, and SdeC (known as the SidE family of effectors) are secreted into host cells, where they localize to the cytoplasmic face of the Legionella containing vacuole (LCV) in the early stages of infection. SidJ, another effector that is unrelated to the SidE family, is also encoded in the sdeC-sdeA locus. Interestingly, while over-expression of SidE family proteins in a wild type Legionella strain has no effect, we found that their over-expression in a ∆sidJ mutant completely inhibits intracellular growth of the strain. In addition, we found expression of SidE proteins is toxic in both yeast and mammalian HEK293 cells, but this toxicity can be suppressed by co-expression of SidJ, suggesting that SidJ may modulate the function of SidE family proteins. Finally, we were able to demonstrate both in vivo and in vitro that SidJ acts on SidE proteins to mediate their disappearance from the LCV, thereby preventing lethal intoxication of host cells. Based on these findings, we propose that SidJ acts as a metaeffector to control the activity of other Legionella effectors.

Analysis of the association of the expression of KiSS-1 in colorectal cancer tissues with the pathology and prognosis.

PubMed

Huo, Xinkai; Zhang, Lei; Li, Tao

2018-03-01

Colorectal cancer is a common malignant tumor of the digestive tract with high morbidity and mortality rates. The aim of the present study was to examine the expression level of KiSS-1 in tumor tissues of patients with colorectal cancer, and to explore the relationship with the clinicopathology and prognosis of patients with colorectal cancer. Frozen tumor tissue and corresponding cancer-adjacent normal tissue specimens were selected from 56 patients with colorectal cancer who were treated in the Department of Surgery of our hospital from May 2009 to December 2011. The expression levels of KiSS-1 messenger ribonucleic acid (mRNA) in tumor tissues and cancer-adjacent normal tissues were detected by reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR). The expression levels of KiSS-1 proteins in colorectal cancer tissues and cancer-adjacent normal tissues were further detected by immunohistochemistry. In addition, the association of the expression level of KiSS-1 proteins in tissues of colorectal cancer patients with pathological parameters and the prognosis of patients with colorectal cancer was analyzed combined with clinical data. The RT-qPCR results showed that the expression of KiSS-1 mRNA in colorectal cancer tissues was significantly lower than that in cancer-adjacent normal tissues (P<0.05). Immunohistochemistry results indicated that the positive expression rate of KiSS-1 proteins in colorectal cancer tissues (26.79%) was significantly lower than that in cancer-adjacent normal tissues (80.36%). The low expression of KiSS-1 in colorectal cancer tissues was associated with the degree of differentiation, invasion and metastasis, as well as clinical staging. The 5-year overall survival rate of patients with colorectal cancer was 55.36% (31/56). The univariate survival analysis showed that patients with lowly expressed KiSS-1 had worse prognosis. The low expression of KiSS-1 is closely associated with the occurrence and development of colorectal

Chemostat studies of bacteriophage M13 infected Escherichia coli JM109 for continuous ssDNA production.

PubMed

Kick, Benjamin; Behler, Karl Lorenz; Severin, Timm Steffen; Weuster-Botz, Dirk

2017-09-20

Steady state studies in a chemostat enable the control of microbial growth rate at defined reaction conditions. The effects of bacteriophage M13 infection on maximum growth rate of Escherichia coli JM109 were studied in parallel operated chemostats on a milliliter-scale to analyze the steady state kinetics of phage production. The bacteriophage infection led to a decrease in maximum specific growth rate of 15% from 0.74h -1 to 0.63h -1 . Under steady state conditions, a constant cell specific ssDNA formation rate of 0.15±0.004 mg ssDNA g CDW -1 h -1 was observed, which was independent of the growth rate. Using the estimated kinetic parameters for E. coli infected with bacteriophage M13, the ssDNA concentration in the steady state could be predicted as function of the dilution rate and the glucose concentration in the substrate. Scalability of milliliter-scale data was approved by steady state studies on a liter-scale at a selected dilution rate. An ssDNA space-time yield of 5.7mgL -1 h -1 was achieved with increased glucose concentration in the feed at a dilution rate of 0.3h -1 , which is comparable to established fed-batch fermentation with bacteriophage M13 for ssDNA production. Copyright © 2017 Elsevier B.V. All rights reserved.

Pseudomonas aeruginosa uses T3SS to inhibit diabetic wound healing

PubMed Central

Goldufsky, Josef; Wood, Stephen J.; Jayaraman, Vijayakumar; Majdobeh, Omar; Chen, Lin; Qin, Shanshan; Zhang, Chunxiang; DiPietro, Luisa A.; Shafikhani, Sasha H.

2015-01-01

Diabetic foot ulcers are responsible for more hospitalizations than any other complication of diabetes. Bacterial infection is recognized as an important factor associated with impaired healing in diabetic ulcers. Pseudomonas aeruginosa is the most frequently detected Gram-negative pathogen in diabetic ulcers. P. aeruginosa infection has been shown to impair healing in diabetic wounds in a manner that correlates with its ability to form biofilm. While the majority of infections in diabetic ulcers are biofilm associated, 33% of infections are nonbiofilm in nature. P. aeruginosa is the most prevalent Gram-negative pathogen in all diabetic wound types, which suggests that the deleterious impact of P. aeruginosa on healing in diabetic wounds goes beyond its ability to form biofilm and likely involves other factors. The Type III Secretion System (T3SS) virulence structure is required for the pathogenesis of all P. aeruginosa clinical isolates, suggesting that it may also play a role in the inhibition of wound repair in diabetic skin ulcers. We evaluated the role of T3SS in mediating P. aeruginosa–induced tissue damage in the wounds of diabetic mice. Our data demonstrate that P. aeruginosa establishes a robust and persistent infection in diabetic wounds independent of its ability to form biofilm and causes severe wound damage in a manner that primarily depends on its T3SS. PMID:25912785

Pseudomonas aeruginosa uses T3SS to inhibit diabetic wound healing.

PubMed

Goldufsky, Josef; Wood, Stephen J; Jayaraman, Vijayakumar; Majdobeh, Omar; Chen, Lin; Qin, Shanshan; Zhang, Chunxiang; DiPietro, Luisa A; Shafikhani, Sasha H

2015-01-01

Diabetic foot ulcers are responsible for more hospitalizations than any other complication of diabetes. Bacterial infection is recognized as an important factor associated with impaired healing in diabetic ulcers. Pseudomonas aeruginosa is the most frequently detected Gram-negative pathogen in diabetic ulcers. P. aeruginosa infection has been shown to impair healing in diabetic wounds in a manner that correlates with its ability to form biofilm. While the majority of infections in diabetic ulcers are biofilm associated, 33% of infections are nonbiofilm in nature. P. aeruginosa is the most prevalent Gram-negative pathogen in all diabetic wound types, which suggests that the deleterious impact of P. aeruginosa on healing in diabetic wounds goes beyond its ability to form biofilm and likely involves other factors. The Type III Secretion System (T3SS) virulence structure is required for the pathogenesis of all P. aeruginosa clinical isolates, suggesting that it may also play a role in the inhibition of wound repair in diabetic skin ulcers. We evaluated the role of T3SS in mediating P. aeruginosa-induced tissue damage in the wounds of diabetic mice. Our data demonstrate that P. aeruginosa establishes a robust and persistent infection in diabetic wounds independent of its ability to form biofilm and causes severe wound damage in a manner that primarily depends on its T3SS. © 2015 by the Wound Healing Society.

TIMES-SS--recent refinements resulting from an industrial skin sensitisation consortium.

PubMed

Patlewicz, G; Kuseva, C; Mehmed, A; Popova, Y; Dimitrova, G; Ellis, G; Hunziker, R; Kern, P; Low, L; Ringeissen, S; Roberts, D W; Mekenyan, O

2014-01-01

The TImes MEtabolism Simulator platform for predicting Skin Sensitisation (TIMES-SS) is a hybrid expert system, first developed at Bourgas University using funding and data from a consortium of industry and regulators. TIMES-SS encodes structure-toxicity and structure-skin metabolism relationships through a number of transformations, some of which are underpinned by mechanistic 3D QSARs. The model estimates semi-quantitative skin sensitisation potency classes and has been developed with the aim of minimising animal testing, and also to be scientifically valid in accordance with the OECD principles for (Q)SAR validation. In 2007 an external validation exercise was undertaken to fully address these principles. In 2010, a new industry consortium was established to coordinate research efforts in three specific areas: refinement of abiotic reactions in the skin (namely autoxidation) in the skin, refinement of the manner in which chemical reactivity was captured in terms of structure-toxicity rules (inclusion of alert reliability parameters) and defining the domain based on the underlying experimental data (study of discrepancies between local lymph node assay Local Lymph Node Assay (LLNA) and Guinea Pig Maximisation Test (GPMT)). The present paper summarises the progress of these activities and explains how the insights derived have been translated into refinements, resulting in increased confidence and transparency in the robustness of the TIMES-SS predictions.

Effect of five lubricants on life of AISI 9310 spur gears

NASA Technical Reports Server (NTRS)

Townsend, D. P.; Zaretsky, E. V.

1985-01-01

Spur-gear surface fatigue tests were conducted with five lubricants using a single lot of consumable-electrode vacuum melted (CVM) AISI 9310 spur gears. The lot of gears was divided into five groups, each of which was tested with a different lubricant. The test lubricants are classified as either a synthetic hydrocarbon, mineral oil, or ester-based lubricant. All five lubricants have imilar viscosity and pressure-viscosity coefficients. A pentaerythritol base stock without sufficient antiwear additives produced a surface fatigue life pproximately 22 percent that of the same base stock with chlorine and phosphorus type additives. The presence of sulfur type antiwear additives in the lubricant did not appear to affect the surface fatigue life of the gears tested. No statistical difference in the 10-percent surface fatigue life was produced with four of the five lubricants.

Influence of processing parameters on the characteristics of surface layers of low temperature plasma nitrocarburized AISI 630 martensitic stainless steel

NASA Astrophysics Data System (ADS)

Lee, Insup

2017-11-01

Plasma nitrocarburizing was performed on solution-treated AISI 630 martensitic precipitation hardening stainless steel samples with a gas mixture of H2, N2, and CH4 with changing temperature, discharge voltage and amount of CH4. When nitrocarburized with increasing temperature from 380 °C to 430 °C at fixed 25% N2 and 6% CH4, the thickness of expanded martensite (α'N) layer and surface hardness increased up to 10 μm and 1323 HV0.05, respectively but the corrosion resistance decreased. Though the increase of discharge voltage from 400 V to 600 V increased α'N layer thickness and surface hardness (up to 13 μm and 1491 HV0.05, respectively), the treated samples still showed very poor corrosion behavior. Thus, to further improve the corrosion resistance, the influence of variation of the amount of CH4 in the nitrocarburizing process was investigated. Increasing the CH4 percentage aided higher corrosion resistance, although it decreased the α'N layer thickness. The most appropriate conditions for moderate α'N layer thickness, high surface hardness and better corrosion resistance than the solution-treated bare sample were established, which is plasma nitrocarburizing at 400 °C with 400 V discharge voltage and containing 25% N2 and 4% CH4.

ssHMM: extracting intuitive sequence-structure motifs from high-throughput RNA-binding protein data

PubMed Central

Krestel, Ralf; Ohler, Uwe; Vingron, Martin; Marsico, Annalisa

2017-01-01

Abstract RNA-binding proteins (RBPs) play an important role in RNA post-transcriptional regulation and recognize target RNAs via sequence-structure motifs. The extent to which RNA structure influences protein binding in the presence or absence of a sequence motif is still poorly understood. Existing RNA motif finders either take the structure of the RNA only partially into account, or employ models which are not directly interpretable as sequence-structure motifs. We developed ssHMM, an RNA motif finder based on a hidden Markov model (HMM) and Gibbs sampling which fully captures the relationship between RNA sequence and secondary structure preference of a given RBP. Compared to previous methods which output separate logos for sequence and structure, it directly produces a combined sequence-structure motif when trained on a large set of sequences. ssHMM’s model is visualized intuitively as a graph and facilitates biological interpretation. ssHMM can be used to find novel bona fide sequence-structure motifs of uncharacterized RBPs, such as the one presented here for the YY1 protein. ssHMM reaches a high motif recovery rate on synthetic data, it recovers known RBP motifs from CLIP-Seq data, and scales linearly on the input size, being considerably faster than MEMERIS and RNAcontext on large datasets while being on par with GraphProt. It is freely available on Github and as a Docker image. PMID:28977546

SS-mPEG chemical modification of recombinant phospholipase C for enhanced thermal stability and catalytic efficiency.

PubMed

Fang, Xian; Wang, Xueting; Li, Guiling; Zeng, Jun; Li, Jian; Liu, Jingwen

2018-05-01

PEGylation is one of the most promising and extensively studied strategies for improving the properties of proteins as well as enzymic physical and thermal stability. Phospholipase C, hydrolyzing the phospholipids offers tremendous applications in diverse fields. However, the poor thermal stability and higher cost of production have restricted its industrial application. This study focused on improving the stabilization of recombinant PLC by chemical modification with methoxypolyethylene glycol-Succinimidyl Succinate (SS-mPEG, MW 5000). PLC gene from isolate Bacillus cereus HSL3 was fused with SUMO, a novel small ubiquitin-related modifier expression vector and over expressed in Escherichia coli. The soluble fraction of SUMO-PLC reached 80% of the total recombinant protein. The enzyme exhibited maximum catalytic activity at 80 °C and was relatively thermostable at 40-70 °C. It showed extensive substrate specificity pattern and marked activity toward phosphatidylcholine, which made it a typical non-specific PLC for industrial purpose. SS-mPEG-PLC complex exhibited an enhanced thermal stability at 70-80 °C and the catalytic efficiency (K cat /K m ) had increased by 3.03 folds compared with free PLC. CD spectrum of SS-mPEG-PLC indicated a possible enzyme aggregation after chemical modification, which contributed to the higher thermostability of SS-mPEG-PLC. The increase of antiparallel β sheets in secondary structure also made it more stable than parallel β sheets. The presence of SS-mPEG chains on the enzyme molecule surface somewhat changed the binding rate of the substrates, leading to a significant improvement in catalytic efficiency. This study provided an insight into the addition of SS-mPEG for enhancing the industrial applications of phospholipase C at higher temperature. Copyright © 2018 Elsevier B.V. All rights reserved.

Wear resistance of CuZr-based amorphous-forming alloys against bearing steel in 3.5% NaCl solution

NASA Astrophysics Data System (ADS)

Ji, Xiulin; Wang, Hui; Bao, Yayun; Zheng, Dingcong

2017-11-01

To investigate the amorphous-crystalline microstructure on the tribocorrosion of bulk metallic glasses (BMGs), 6 mm diameter rods of Cu46-xZr47Al7Agx (x = 0, 2, 4) amorphous-forming alloys with in situ crystalline and amorphous phases were fabricated by arc-melting and Cu-mould casting. Using a pin-on-disc tribometer, the tribo-pair composed by CuZr-based amorphous-forming alloys and AISI 52100 steel were studied in 3.5% NaCl solution. With the increase of Ag content from 0 to 4 at.%, the compressive fracture strength and the average hardness decrease firstly and then increase. Moreover, 4 at.% Ag addition increases the amount of amorphous phase obviously and inhibits the formation of brittle crystalline phase, resulting in the improvement of corrosion resistance and the corrosive wear resistance. The primary wear mechanism of the BMG composites is abrasive wear accompanying with corrosive wear. The tribocorrosion mass loss of Cu42Zr47Al7Ag4 composite is 1.5 mg after 816.8 m sliding distance at 0.75 m s-1 sliding velocity under 10 N load in NaCl solution. And the volume loss evaluated from the mass loss is about 20 times lower than that of AISI 304 SS. Thus, Cu42Zr47Al7Ag4 composite may be a good candidate in the tribology application under marine environment.

Efficient Computation of Sparse Matrix Functions for Large-Scale Electronic Structure Calculations: The CheSS Library.

PubMed

Mohr, Stephan; Dawson, William; Wagner, Michael; Caliste, Damien; Nakajima, Takahito; Genovese, Luigi

2017-10-10

We present CheSS, the "Chebyshev Sparse Solvers" library, which has been designed to solve typical problems arising in large-scale electronic structure calculations using localized basis sets. The library is based on a flexible and efficient expansion in terms of Chebyshev polynomials and presently features the calculation of the density matrix, the calculation of matrix powers for arbitrary powers, and the extraction of eigenvalues in a selected interval. CheSS is able to exploit the sparsity of the matrices and scales linearly with respect to the number of nonzero entries, making it well-suited for large-scale calculations. The approach is particularly adapted for setups leading to small spectral widths of the involved matrices and outperforms alternative methods in this regime. By coupling CheSS to the DFT code BigDFT, we show that such a favorable setup is indeed possible in practice. In addition, the approach based on Chebyshev polynomials can be massively parallelized, and CheSS exhibits excellent scaling up to thousands of cores even for relatively small matrix sizes.

Influence of cryogenic treatment on microstructure and mechanical properties of high strength AISI D2 tool steel =

NASA Astrophysics Data System (ADS)

Ghasemi Nanesa, Hadi

Cryogenic treatment, known as treating materials at sub-zero temperatures, has been added to conventional heat treatment cycle of high alloyed steels where martensitic transformation is incomplete after quenching to room temperature. Incomplete martensitic transformation occurs due to the effect of high content of alloying elements on pushing down martensite start and finish temperatures to very low values, specifically, on tool steels. In spite of obtaining significant improvements in mechanical and wear properties after cryogenic treatment, there is no cohesive picture about what exactly modifies the microstructure of tool steels during cryogenic treatment and therefore divergent opinions on the influence of process parameters are still reported. For example, the suggested time length for cryogenic treatment starts from few seconds to several days indicating the lack of understanding about micromechanisms responsible for microstructural evolution while holding at cryogenic temperatures. In this regard, the main objective of this project is to develop a better understanding on the fundamental micromechanisms operating during cryogenic treatment. To attain this objective, the following milestones are pursued. - To study the conventional cryogenic treatment and finding challenges. - To identify and characterize the optimum starting microstructure before cryogenic treatment. - To determine the important processing parameters those control the evolution of microstructure and hardness. - To investigate the interaction between carbide precipitation and martensitic transformation in the AISI D2 steel. - To propose an optimal cryogenic treatment for AISI D2 steel.

Effect of surface etching on the oxidation behavior of plasma chromizing-treated AISI440B stainless steel

NASA Astrophysics Data System (ADS)

Meng, T. X.; Guo, Q.; Xi, W.; Ding, W. Q.; Liu, X. Z.; Lin, N. M.; Yu, S. W.; Liu, X. P.

2018-03-01

Double glow plasma surface alloying was applied to prepare chromizing layer in the surface of AISI440B stainless steel. Prior to chromizing, the stainless steel was etched by microwave plasma chemical vapor deposition to change the surface morphology and composition, and then heated for chromizing at 950 °C for 3 h. The cyclical oxidation of steel after chromizing was carried out at 900 °C for 100 h. Scanning electron microscopy, glow discharge optical emission spectrometer and X-ray diffractometer were used to characterize microstructure, composition and phase structure of alloyed and oxidized samples. The results show that the surface was composed of the Cr-rich top layer and Cr23C6, Cr7C3 and {Cr,Fe}7C3 below layer after chromizing. The bonding between the chromizing layer and the substrate after etching treatment was obviously strengthened. AISI440B steel shows a poor oxidation resistance and the weight gain oxidized for 100 h was up to 31.1 mg/cm2. Weight gains for chromizing and etching + chromizing treated samples were 0.67 mg/cm2 and 8 mg/cm2, respectively. Both oxidized surfaces of chromizing and etching + chromizing were composed of Cr2O3, but the oxide scale of etching + chromizing treated samples was more compact than that of samples without etching.

Starch synthase 4 is essential for coordination of starch granule formation with chloroplast division during Arabidopsis leaf expansion

PubMed Central

Crumpton-Taylor, Matilda; Pike, Marilyn; Lu, Kuan-Jen; Hylton, Christopher M; Feil, Regina; Eicke, Simona; Lunn, John E; Zeeman, Samuel C; Smith, Alison M

2013-01-01

Arabidopsis thaliana mutants lacking the SS4 isoform of starch synthase have strongly reduced numbers of starch granules per chloroplast, suggesting that SS4 is necessary for the normal generation of starch granules. To establish whether it plays a direct role in this process, we investigated the circumstances in which granules are formed in ss4 mutants. Starch granule numbers and distribution and the accumulation of starch synthase substrates and products were investigated during ss4 leaf development, and in ss4 mutants carrying mutations or transgenes that affect starch turnover or chloroplast volume. We found that immature ss4 leaves have no starch granules, but accumulate high concentrations of the starch synthase substrate ADPglucose. Granule numbers are partially restored by elevating the capacity for glucan synthesis (via expression of bacterial glycogen synthase) or by increasing the volumes of individual chloroplasts (via introduction of arc mutations). However, these granules are abnormal in distribution, size and shape. SS4 is an essential component of a mechanism that coordinates granule formation with chloroplast division during leaf expansion and determines the abundance and the flattened, discoid shape of leaf starch granules. PMID:23952675

Thermal and non-thermal X-rays from the Galactic supernova remnant G348.5+0.1

NASA Astrophysics Data System (ADS)

Yamauchi, Shigeo; Minami, Sari; Ota, Naomi; Koyama, Katsuji

2014-02-01

We report on Suzaku results of the two distinct regions in the Galactic supernova remnant G348.5+0.1: extended thermal X-rays ("soft diffuse") at the north-east region and non-thermal X-rays (CXOU J171419.8-383023) at the north-west region. The X-ray spectrum of the soft diffuse X-rays can be fitted with neither an ionization equilibrium nor a non-equilibrium (ionizing) plasma model, leaving saw- tooth residuals in the 1.5-3 keV energy band. The residual structures can be produced when free electrons are recombined to the K-shells of highly ionized Mg and Si ions. In fact, the X-ray spectrum is nicely fitted with a recombination-dominant plasma model. We propose a scenario whereby the plasma in a nearly fully ionized state at high temperature quickly changed to a recombining phase due to selective cooling of electrons to a lower temperature of ˜ 0.5 keV. The spectrum of CXOU J171419.8-383023 is well explained by a simple power-law model with a photon index of 1.9, nearly equal to the typical value for pulsar wind nebulae. Since the distance is estimated to be the same as that of the soft diffuse radiation, we infer that both the soft diffuse X-rays and CXOU J171419.8-383023 are associated with the same object, SNR G348.5+0.1.

Studies with pyrethroids (kadethrin and deltamethrin) and lindane in ethanol sensitive (LS) and insensitive (SS) mouse strains

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

Doherty, J.; Baker, R.C.; Deitrich, R.

1990-02-26

Ethanol (E) sensitive (LS) and insensitive (SS) mouse strains are distinguished by their sleeping time to a given dose of E and the locus for this difference is at the level of the neuron. In attempts to understand the neuropharmacological basis of insecticide action and to further define the differences in these mouse lines, LS and SS mice were dosed with type I (kadethrine, K) and II (deltamethrin, D) pyrethroids and lindane (L). These compounds were selected because their proposed modes of action are on the Na+ channel (K and D) and/or the GABA receptor ionophore (D and L). Nomore » consistent differences in the effects of K, D or L in the SS and LS mouse lines were evident. In preliminary studies both SS and LS mice dosed with 50 or 100 {mu}g/brain of L (intracerebroventricularly) but not D slept much longer (2-3X) than when dosed with E alone, an effect opposite of that predicted from L's known excitatory action. These data indicate that as far as can be distinguished by pyrethroids and L, the Na+ channel and GABA receptor/ionophore complex are similar in both the LS and SS mouse lines.« less

Resistance of superhydrophobic and oleophobic surfaces to varied temperature applications on 316L SS

NASA Astrophysics Data System (ADS)

Shams, Hamza; Basit, Kanza; Saleem, Sajid; Siddiqui, Bilal A.

316L SS also called Marine Stainless Steel is an important material for structural and marine applications. When superhydrophobic and oleophobic coatings are applied on 316L SS it shows significant resistance to wear and corrosion. This paper aims to validate the coatings manufacturer's information on optimal temperature range and test the viability of coating against multiple oil based cleaning agents. 316L SS was coated with multiple superhydrophic and oleohobic coatings and observed under SEM for validity of adhesion and thickness and then scanned under FFM to validate the tribological information. The samples were then dipped into multiple cleaning agents maintained at the range of operating temperatures specified by the manufacturer. Coating was observed for deterioration over a fixed time intervals through SEM and FFM. A comparison was drawn to validate the most critical cleaning agent and the most critical temperature at which the coating fails to leave the base substrate exposed to the environment.

The effect of some heat treatment parameters on the dimensional stability of AISI D2

NASA Astrophysics Data System (ADS)

Surberg, Cord Henrik; Stratton, Paul; Lingenhöle, Klaus

2008-01-01

The tool steel AISI D2 is usually processed by vacuum hardening followed by multiple tempering cycles. It has been suggested that a deep cold treatment in between the hardening and tempering processes could reduce processing time and improve the final properties and dimensional stability. Hardened blocks were then subjected to various combinations of single and multiple tempering steps (520 and 540 °C) and deep cold treatments (-90, -120 and -150 °C). The greatest dimensional stability was achieved by deep cold treatments at the lowest temperature used and was independent of the deep cold treatment time.

Microstructure Characterization and Corrosion Properties of Nitrocarburized AISI 4140 Low Alloy Steel

NASA Astrophysics Data System (ADS)

Fattah, M.; Mahboubi, F.

2012-04-01

Plasma nitrocarburizing treatments of AISI 4140 low alloy steel have been carried out in a gas mixture of 85% N2-12% H2-3% CO2. All treatments were performed for 5 h at a chamber pressure of 4 mbar. Different treatment temperatures varying from 520 to 620 °C have been used to investigate the effect of treatment temperature on the corrosion and hardness properties and also microstructure of the plasma nitrocarburized steel. Scanning electron and optical microscopy, x-ray diffraction, microhardness measurement, and potentiodynamic polarization technique in 3.5% NaCl solution were used to study the treated surfaces. The results revealed that plasma nitrocarburizing at temperatures below 570 °C can readily produce a monophase ɛ compound layer. The compound layer formed at 620 °C is composed of two sub-layers and is supported by an austenite zone followed by the diffusion layer. The thickest diffusion layer was related to the sample treated at 620 °C. Microhardness results showed a reduction of surface hardness with increasing the treatment temperature from 520 to 620 °C. It has also been found that with increasing treatment temperature from 520 to 545 °C the corrosion resistance increases up to a maximum and then decreases with further increasing treatment temperature from 545 to 620 °C.

Kinetic of carbonaceous substrate in an upflow anaerobic sludge sludge blanket (UASB) reactor treating 2,4 dichlorophenol (2,4 DCP).

PubMed

Sponza, Delia Teresa; Uluköy, Ayşen

2008-01-01

The performance of an upflow anaerobic sludge blanket (UASB) reactor treating 2,4 dichlorophenol (2,4 DCP) was evaluated at different hydraulic retention times (HRTs) using synthetic wastewater in order to obtain the growth substrate (glucose-COD) and 2,4 DCP removal kinetics. Treatment efficiencies of the UASB reactor were investigated at different hydraulic retention times (2-20 h) corresponding to a food to mass (F/M) ratio of 1.2-1.92 g-COD g(-1) VSS day(-1). A total of 65-83% COD removal efficiencies were obtained at HRTs of 2-20 h. In all, 83% and 99% 2,4 DCP removals were achieved at the same HRTs in the UASB reactor. Conventional Monod, Grau Second-order and Modified Stover-Kincannon models were applied to determine the substrate removal kinetics of the UASB reactor. The experimental data obtained from the kinetic models showed that the Monod kinetic model is more appropriate for correlating the substrate removals compared to the other models for the UASB reactor. The maximum specific substrate utilization rate (k) (mg-COD mg(-1) SS day(-1)), half-velocity concentration (K(s)) (mg COD l(-1)), growth yield coefficient (Y) (mg mg(-1)) and bacterial decay coefficient (b) (day(-1)) were 0.954 mg-COD mg(-1) SS day(-1), 560.29 mg-COD l(-1), 0.78 mg-SS g(-1)-COD, 0.093 day(-1) in the Conventional Monod kinetic model. The second-order kinetic coefficient (k(2)) was calculated as 0.26 day(-1) in the Grau reaction kinetic model. The maximum COD removal rate constant (U(max)) and saturation value (K(B)) were calculated as 7.502 mg CODl(-1)day(-1) and 34.56 mg l(-1)day(-1) in the Modified Stover-Kincannon Model. The (k)(mg-2,4 DCP mg(-1) SS day(-1)), (K(s)) (mg 2,4 DCPl(-1)), (Y) (mg SS mg(-1) 2,4 DCP) and (k(d)) (day(-1)) were 0.0041 mg-2,4 DCP mg(-1) SS day(-1), 2.06 mg-COD l(-1), 0.0017 mg-SS mg(-1) 2,4 DCP and 3.1 x 10(-5) day(-1) in the Conventional Monod kinetic model for 2,4 DCP degradation. The second-order kinetic coefficient (k(2)) was calculated as 0.30 day

First insights into the genetic diversity of Echinococcus granulosus sensu stricto (s.s.) in Serbia.

PubMed

Debeljak, Zoran; Boufana, Belgees; Interisano, Maria; Vidanovic, Dejan; Kulisic, Zoran; Casulli, Adriano

2016-06-15

Cystic echinococcosis (CE) caused by Echinococcus granulosus sensu stricto (s.s.) is a cosmopolitan zoonotic infection which is endemic in Serbia where it is subject to mandatory reporting. However, information on the incidence of the disease in humans and prevalence of hydatid infection in livestock remains limited. We used sequenced data of the cytochrome c oxidase subunit 1 (cox 1) mitochondrial gene to examine the genetic diversity and population structure of E. granulosus (s.s.) from intermediate hosts from Serbia. We also compared our generated nucleotide sequences with those reported for neighbouring European countries. Echinococcus canadensis was molecularly confirmed from pig and human hydatid isolates. E. granulosus (G1) was confirmed from sheep and cattle hydatid isolates as well as the first molecular confirmation in Serbia of E. granulosus G2 in sheep and E. granulosus G3 in sheep and cattle hydatid isolates. The Serbian E. granulosus (s.s.) parsimony network displayed 2 main haplotypes (SB02 and SB05) which together with the neutrality indices were suggestive of bottleneck and/or balancing selection. Haplotype analysis showed the presence of the common E. granulosus haplotype described from other worldwide regions. Investigation of the pairwise fixation (Fst) index suggested that Serbian populations of E. granulosus (s.s.) from sheep and cattle hosts showed moderate genetic differentiation. Six of the Serbian haplotypes (SB02-SB07) were shared with haplotypes from Bulgaria, Hungary and/or Romania. Further studies using a larger number of hydatid isolates from various locations across Serbia will provide more information on the genetic structure of E. granulosus (s.s.) within this region. Copyright © 2016 Elsevier B.V. All rights reserved.

Dynamic Cooperation of Hydrogen Binding and π Stacking in ssDNA Adsorption on Graphene Oxide.

PubMed

Xu, Zhen; Lei, Xiaoling; Tu, Yusong; Tan, Zhi-Jie; Song, Bo; Fang, Haiping

2017-09-21

Functional nanoscale structures consisting of a DNA molecule coupled to graphene or graphene oxide (GO) have great potential for applications in biosensors, biomedicine, nanotechnology, and materials science. Extensive studies using the most sophisticated experimental techniques and theoretical methods have still not clarified the dynamic process of single-stranded DNA (ssDNA) adsorbed on GO surfaces. Based on a molecular dynamics simulation, this work shows that an ssDNA segment could be stably adsorbed on a GO surface through hydrogen bonding and π-π stacking interactions, with preferential binding to the oxidized rather than to the unoxidized region of the GO surface. The adsorption process shows a dynamic cooperation adsorption behavior; the ssDNA segment first captures the oxidized groups of the GO surface by hydrogen bonding interaction, and then the configuration relaxes to maximize the π-π stacking interactions between the aromatic rings of the nucleobases and those of the GO surface. We attributed this behavior to the faster forming hydrogen bonding interaction compared to π-π stacking; the π-π stacking interaction needs more relaxation time to regulate the configuration of the ssDNA segment to fit the aromatic rings on the GO surface. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Identification of serine 348 on the apelin receptor as a novel regulatory phosphorylation site in apelin-13-induced G protein-independent biased signaling.

PubMed

Chen, Xiaoyu; Bai, Bo; Tian, Yanjun; Du, Hui; Chen, Jing

2014-11-07

Phosphorylation plays vital roles in the regulation of G protein-coupled receptor (GPCR) functions. The apelin and apelin receptor (APJ) system is involved in the regulation of cardiovascular function and central control of body homeostasis. Here, using tandem mass spectrometry, we first identified phosphorylated serine residues in the C terminus of APJ. To determine the role of phosphorylation sites in APJ-mediated G protein-dependent and -independent signaling and function, we induced a mutation in the C-terminal serine residues and examined their effects on the interaction between APJ with G protein or GRK/β-arrestin and their downstream signaling. Mutation of serine 348 led to an elimination of both GRK and β-arrestin recruitment to APJ induced by apelin-13. Moreover, APJ internalization and G protein-independent ERK signaling were also abolished by point mutation at serine 348. In contrast, this mutant at serine residues had no demonstrable impact on apelin-13-induced G protein activation and its intracellular signaling. These findings suggest that mutation of serine 348 resulted in inactive GRK/β-arrestin. However, there was no change in the active G protein thus, APJ conformation was biased. These results provide important information on the molecular interplay and impact of the APJ function, which may be extrapolated to design novel drugs for cardiac hypertrophy based on this biased signal pathway. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Assuring SS7 dependability: A robustness characterization of signaling network elements

NASA Astrophysics Data System (ADS)

Karmarkar, Vikram V.

1994-04-01

Current and evolving telecommunication services will rely on signaling network performance and reliability properties to build competitive call and connection control mechanisms under increasing demands on flexibility without compromising on quality. The dimensions of signaling dependability most often evaluated are the Rate of Call Loss and End-to-End Route Unavailability. A third dimension of dependability that captures the concern about large or catastrophic failures can be termed Network Robustness. This paper is concerned with the dependability aspects of the evolving Signaling System No. 7 (SS7) networks and attempts to strike a balance between the probabilistic and deterministic measures that must be evaluated to accomplish a risk-trend assessment to drive architecture decisions. Starting with high-level network dependability objectives and field experience with SS7 in the U.S., potential areas of growing stringency in network element (NE) dependability are identified to improve against current measures of SS7 network quality, as per-call signaling interactions increase. A sensitivity analysis is presented to highlight the impact due to imperfect coverage of duplex network component or element failures (i.e., correlated failures), to assist in the setting of requirements on NE robustness. A benefit analysis, covering several dimensions of dependability, is used to generate the domain of solutions available to the network architect in terms of network and network element fault tolerance that may be specified to meet the desired signaling quality goals.

Presence of T3SS2β genes in trh⁺ Vibrio parahaemolyticus isolated from seafood harvested along Mangalore coast, India.

PubMed

Kumar, B K; Deekshit, V K; Rai, P; Shekar, M; Karunasagar, I; Karunasagar, I

2014-05-01

Vibrio parahaemolyticus is a seafood-borne pathogen autochthonous to the marine and estuarine ecosystem, responsible for gastroenteritis when contaminated raw seafood is consumed. The pathogenicity has been associated with thermostable direct haemolysin (TDH) and TDH-related haemolysin (TRH). Of late, the presence of T3SS2α and T3SS2β gene clusters has been well documented in clinical isolates of Vibrio parahaemolyticus and known to play an essential role in pathogenesis. However, reports on the presence of T3SSβ genes in V. parahaemolyticus isolated from the seafood and/or environmental samples are scanty. In this study, we have identified and analysed the distribution of the T3SS2β genes in V. parahaemolyticus isolated from seafood harvested along southwest coast of India. Results showed that T3SS2β genes are solely associated with trh⁺ and tdh⁺ /trh⁺ strains of V. parahaemolyticus. Reverse transcriptase PCR (RT-PCR) showed that the T3SS2β genes identified in trh⁺ V. parahaemolyticus were transcriptionally active. To our knowledge, this study appears to be the first description on the presence of T3SS2β-positive V. parahaemolyticus isolated from seafood in India. The study of T3SS2 along with other virulence factors will help in better understanding of the risk of seafood-borne illness due to V. parahaemolyticus. T3SSs (α or β) are the important virulence factors of Vibrio parahaemolyticus that contribute to their pathogenicity in humans. This study demonstrated the presence of T3SS2β genes in V. parahaemolyticus isolated from the seafood harvested along Mangalore coast. RT-PCR showed that the T3SS2β genes identified in seafood isolates of V. parahaemolyticus were found to be functional. To the best of our knowledge, this is the first description of T3SS2β genes in trh⁺ V. parahaemolyticus isolated from seafood in India. The presence of T3SS2 along with other virulence factors such as TDH and/or TRH highlights a potential health risk for

Draft genome sequence of Streptomyces sp. strain SS, which produces a series of uridyl peptide antibiotic sansanmycins.

PubMed

Wang, Lifei; Xie, Yunying; Li, Qinglian; He, Ning; Yao, Entai; Xu, Hongzhang; Yu, Ying; Chen, Ruxian; Hong, Bin

2012-12-01

Streptomyces sp. SS produces a series of uridyl peptide antibiotic sansanmycins. Here, we present a draft genome sequence of Streptomyces sp. SS containing the biosynthetic gene cluster for the antibiotics. The identification of the biosynthetic gene cluster of sansanmycins may provide further insight into biosynthetic mechanisms for uridyl peptide antibiotics.

Experimental and Numerical Investigation on Micro-Bending of AISI 304 Sheet Metal Using a Low Power Nanosecond Laser

NASA Astrophysics Data System (ADS)

Paramasivan, K.; Das, Sandip; Marimuthu, Sundar; Misra, Dipten

2018-06-01

The aim of this experimental study is to identify and characterize the response related to the effects of process parameters in terms of bending angle for micro-bending of AISI 304 sheet using a low power Nd:YVO4 laser source. Numerical simulation is also carried out through a coupled thermo-mechanical formulation with finite element method using COMSOL MULTIPHYSICS. The developed numerical simulation indicates that bending is caused by temperature gradient mechanism in the present investigation involving laser micro-bending. The results of experiment indicate that bending angle increases with laser power, number of irradiations, and decreases with increase in scanning speed. Moreover, average bending angle increases with number of laser passes and edge effect, defined in terms of relative variation of bending angle (RBAV), decreases monotonically with the number of laser scans. The substrate is damaged over a width of about 80 μm due to the high temperatures experienced during laser forming at a low scanning speed.

Establishment and characterization of the NCC-SS1-C1 synovial sarcoma cell line.

PubMed

Kito, Fusako; Oyama, Rieko; Takai, Yoko; Sakumoto, Marimu; Shiozawa, Kumiko; Qiao, Zhiwei; Uehara, Takenori; Yoshida, Akihiko; Kawai, Akira; Kondo, Tadashi

2018-04-01

Synovial sarcoma is an aggressive mesenchymal malignancy characterized by unique gene fusions. Tissue culture cells are essential tools for further understanding tumorigenesis and anti-cancer drug development; however, only a limited number of well-characterized synovial sarcoma cell lines exist. Thus, the objective of this study was to establish a patient-derived synovial sarcoma cell line. We established a synovial sarcoma cell line from tumor tissue isolated from a 72-year-old female patient. Prepared cells were analyzed for the presence of gene fusions by fluorescence in situ hybridization, RT-PCR, and karyotyping. In addition, the resulting cell line was characterized by viability, short tandem repeat, colony and spheroid formation, and invasion analyses. Differences in gene enrichment between the primary tumor and cell line were examined by mass spectrometric protein expression profiling and KEGG pathway analysis. Our analyses revealed that the primary tumor and NCC-SS1-C1 cell line harbored the SS18-SSX1 fusion gene typical of synovial sarcoma and similar proteomics profiles. In vitro analyses also confirmed that the established cell line harbored invasive, colony-forming, and spheroid-forming potentials. Moreover, drug screening with chemotherapeutic agents and tyrosine kinase inhibitors revealed that doxorubicin, a subset of tyrosine kinase inhibitors, and several molecular targeting drugs markedly decreased NCC-SS1-C1 cell viability. Results from the present study support that the NCC-SS1-C1 cell line will be an effective tool for sarcoma research.

Identification of the Vibrio parahaemolyticus type III secretion system 2-associated chaperone VocC for the T3SS2-specific effector VopC.

PubMed

Akeda, Yukihiro; Kodama, Toshio; Saito, Kazunobu; Iida, Tetsuya; Oishi, Kazunori; Honda, Takeshi

2011-11-01

The enteropathogen Vibrio parahaemolyticus possesses two sets of type III secretion systems, T3SS1 and T3SS2. Effector proteins secreted by these T3SSs are delivered into host cells, leading to cell death or diarrhea. However, it is not known how specific effectors are secreted through a specific T3SS when both T3SSs are expressed within bacteria. One molecule thought to determine secretion specificity is a T3SS-associated chaperone; however, no T3SS2-specific chaperone has been identified. Therefore, we screened T3SS2 chaperone candidates by a pull-down assay using T3SS2 effectors fused with glutathione-S-transferase. A secretion assay revealed that the newly identified cognate chaperone VocC for the T3SS2-specific effector VopC was required for the efficient secretion of the substrate through T3SS2. Further experiments determined the chaperone-binding domain and the amino-terminal secretion signal of the cognate effector. These findings, in addition to the previously identified T3SS1-specific chaperone, VecA, provide a strategy to clarify the specificity of effector secretion through T3SSs of V. parahaemolyticus. 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Reprint of "Echinococcus granulosus sensu stricto (s.s.) from the critically endangered antelope Addax nasomaculatus in Tunisia".

PubMed

Boufana, Belgees; Saïd, Yousra; Dhibi, Mokhtar; Craig, Philip S; Lahmar, Samia

2017-01-01

Echinococcus granulosus sensu lato (s.l.) is a zoonotic disease highly endemic in Tunisia. Canids including stray and semi-stray dogs, jackals and foxes are known as definitive hosts and a wide range of ungulates have been shown to harbour the metacestode hydatid stage and may serve as intermediate hosts. Fertile hydatid cysts of Echinococcus equinus and E. granulosus sensu stricto (s.s.) were recently molecularly identified for the first time from Tunisian donkeys. E. granulosus (s.s.) was also identified from wild boars in Tunisia. Here we report the confirmation of hydatid cysts caused by E. granulosus (s.s.) in the critically endangered antelope, Addax nasomaculatus in Tunisia. DNA-based molecular analysis revealed that A. nasomaculatus was infected with E. granulosus (s.s.) which had a 100% identity with the main globally distributed E. granulosus (s.s.) (EgTu01) haplotype. Cysts of Taenia hydatigena (n=33) were also observed on the liver and in the body cavity. Due to their endangered status and their relatively small numbers, it is unlikely that hydatid infection of A. nasomaculatus will form a major contribution to the epidemiology and transmission of E. granulosus in Tunisia, but infection may result in pathology, morbidity and early mortality, and may still play a role in the perpetuation of the parasite in wildlife cycles. Copyright © 2015 Elsevier B.V. All rights reserved.

ON THE HUBBLE SPACE TELESCOPE TRIGONOMETRIC PARALLAX OF THE DWARF NOVA SS CYGNI

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

Nelan, Edmund P.; Bond, Howard E., E-mail: nelan@stsci.edu, E-mail: heb11@psu.edu

SS Cygni is one of the brightest dwarf novae (DNe), and one of the best studied prototypes of the cataclysmic variables. Astrometric observations with the Fine Guidance Sensors (FGSs) on the Hubble Space Telescope (HST), published in 2004, gave an absolute trigonometric parallax of 6.06 {+-} 0.44 mas. However, recent very long baseline interferometry (VLBI), obtained during radio outbursts of SS Cyg, has yielded a significantly larger absolute parallax of 8.80 {+-} 0.12 mas, as well as a large difference in the direction of the proper motion (PM) compared to the HST result. The VLBI distance reduces the implied luminositymore » of SS Cyg by about a factor of two, giving good agreement with predictions based on accretion-disk theory in order to explain the observed DN outburst behavior. This discrepancy raises the possibility of significant systematic errors in FGS parallaxes and PMs. We have reanalyzed the archival HST/FGS data, including (1) a critical redetermination of the parallaxes of the background astrometric reference stars, (2) updated input values of the reference-star PMs, and (3) correction of the position measurements for color-dependent shifts. Our new analysis yields a PM of SS Cyg that agrees well with the VLBI motion, and an absolute parallax of 8.30 {+-} 0.41 mas, also statistically concordant with the VLBI result at the {approx}1.2 {sigma} level. Our results suggest that HST/FGS parallaxes are free of large systematic errors, when the data are reduced using high-quality input values for the astrometry of the reference stars, and when instrumental signatures are properly removed.« less

Impact of the Arizona NExSS Winter School on Interdisciplinary Knowledge and Attitudes

NASA Astrophysics Data System (ADS)

Huff, Cierra; Burnam-Fink, Michael; Desch, Steven; Apai, Dániel

2018-01-01

The Nexus for Exoplanet System Science (NExSS) is a NASA-funded research coordination network whose focus is on investigating exoplanet diversity and devising strategies for searching for life on exoplanets. The fields of exoplanets and astrobiology are inherently highly interdisciplinary. Progress in these fields demands that researchers with various scientific backgrounds understand the issues and techniques of allied fields of study, including the tools and approaches used to solve different problems, as well as their limitations.In 2016, the NExSS teams at Arizona State University (ASU) and University of Arizona (UA) hosted 32 graduate students and postdoctoral researchers from various scientific backgrounds for one week at the Arizona NExSS Winter School. To bridge the gaps between fields and promote interdisciplinarity, students participated in lessons, field trips, hands-on activities, and a capstone proposal-writing activity. To assess the impact of the School on knowledge and attitudes about other fields, we administered a pre- and post-School questionnaire designed using the Impact Analysis Method of Davis & Scalice (2015).The results show that all participants gained knowledge at the School, especially in areas outside their primary field of study. The questionnaire revealed interesting differences in attitudes as well. When asked whether the geochemistry of Earth without life is predictable, planetary scientists were more likely than average to say yes, and geologists were more likely than average to say no. Their attitudes had converged after participation in the School. These results demonstrate that the Arizona NExSS Winter School was impactful not just in the knowledge gained, but in the interdisciplinary attitudes of students.

YebC controls virulence by activating T3SS gene expression in the pathogen Edwardsiella piscicida.

PubMed

Wei, Lifan; Wu, Yanyan; Qiao, Haoxian; Xu, Wensheng; Zhang, Yuanxing; Liu, Xiaohong; Wang, Qiyao

2018-06-12

Edwardsiella piscicida is an infectious Gram-negative bacterium that causes great losses to the aquaculture industry worldwide. Based on pattern analysis of conditional essentiality (PACE), a new method for transposon insertion sequencing (Tn-seq) data analysis, we investigated the genome-wide genetic requirements during the dynamic process of infection and colonization in turbot in this study. As a result, disruption of ETAE_1437 was discovered to lead to substantially reduced colonization, which was similar to the in vivo dynamic patterns of the mutants of T3SS or T6SS. Bioinformatics analysis indicated that ETAE_1437 is a YebC/PmpR family regulator. Moreover, we found that ETAE_1437 not only regulated quorum sensing by directly binding to the edwR promoter region but also activated T3SS expression by directly binding to the promoter region of the T3SS gene ETAE_0873. In addition, ETAE_1437 mutants exhibited substantial colonization defects and significantly decreased virulence in turbot. Overall, this study identified ETAE_1437 as a novel virulence regulator in E. piscicida and enriched our understanding of the pathogenesis of E. piscicida in fish. We thus reannotated ETAE_1437 as YebC.

ss Component of the Proton and the Strangeness Magnetic Moment

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

Zou, B.S.; Riska, D.O.; Helsinki Institute of Physics and Department of Physical Sciences, POB 64, 00014 University of Helsinki

2005-08-12

A complete analysis is given of the implications of the empirical indications for a positive strangeness magnetic moment {mu}{sub s} of the proton on the possible configurations of the uudss component of the proton. A positive value for {mu}{sub s} is obtained in the ss configuration where the uuds subsystem is in an orbitally excited state with [4]{sub FS}[22]{sub F}[22]{sub S} flavor-spin symmetry, which is likely to have the lowest energy. The configurations in which the s is orbitally excited, which include the conventional K{sup +}{lambda}{sup 0} configuration, with the exception of that in which the uuds component has spinmore » 2, yield negative values for {mu}{sub s}. The hidden strangeness analogues of recently proposed quark cluster models for the {theta}{sup +} pentaquark give differing signs for {mu}{sub s}.« less

Quantitative Evaluation of Aged AISI 316L Stainless Steel Sensitization to Intergranular Corrosion: Comparison Between Microstructural Electrochemical and Analytical Methods

NASA Astrophysics Data System (ADS)

Sidhom, H.; Amadou, T.; Sahlaoui, H.; Braham, C.

2007-06-01

The evaluation of the degree of sensitization (DOS) to intergranular corrosion (IGC) of a commercial AISI 316L austenitic stainless steel aged at temperatures ranging from 550 °C to 800 °C during 100 to 80,000 hours was carried out using three different assessment methods. (1) The microstructural method coupled with the Strauss standard test (ASTM A262). This method establishes the kinetics of the precipitation phenomenon under different aging conditions, by transmission electronic microscope (TEM) examination of thin foils and electron diffraction. The subsequent chromium-depleted zones are characterized by X-ray microanalysis using scanning transmission electronic microscope (STEM). The superimposition of microstructural time-temperature-precipitation (TTP) and ASTM A262 time-temperature-sensitization (TTS) diagrams provides the relationship between aged microstructure and IGC. Moreover, by considering the chromium-depleted zone characteristics, sensitization and desensitization criteria could be established. (2) The electrochemical method involving the double loop-electrochemical potentiokinetic reactivation (DL-EPR) test. The operating conditions of this test were initially optimized using the experimental design method on the bases of the reliability, the selectivity, and the reproducibility of test responses for both annealed and sensitized steels. The TTS diagram of the AISI 316L stainless steel was established using this method. This diagram offers a quantitative assessment of the DOS and a possibility to appreciate the time-temperature equivalence of the IGC sensitization and desensitization. (3) The analytical method based on the chromium diffusion models. Using the IGC sensitization and desensitization criteria established by the microstructural method, numerical solving of the chromium diffusion equations leads to a calculated AISI 316L TTS diagram. Comparison of these three methods gives a clear advantage to the nondestructive DL-EPR test when it is

Sequence analysis of mitochondrial ND1 gene can reveal the genetic structure and origin of Bactrocera dorsalis s.s.

PubMed Central

2014-01-01

Background The oriental fruit fly, Bactrocera dorsalis s.s., is one of the most important quarantine pests in many countries, including China. Although the oriental fruit fly has been investigated extensively, its origins and genetic structure remain disputed. In this study, the NADH dehydrogenase subunit 1 (ND1) gene was used as a genetic marker to examine the genetic diversity, population structure, and gene flow of B. dorsalis s.s. throughout its range in China and southeast Asia. Results Haplotype networks and phylogenetic analysis indicated two distinguishable lineages of the fly population but provided no strong support for geographical subdivision in B. philippinensis. Demographic analysis revealed rapid expansion of B. dorsalis s.s. populations in China and Southeast Asia in the recent years. The greatest amount of genetic diversity was observed in Manila, Pattaya, and Bangkok, and asymmetric migration patterns were observed in different parts of China. The data collected here further show that B. dorsalis s.s. in Yunnan, Guangdong, and Fujian Provinces, and in Taiwan might have different origins within southeast Asia. Conclusions Using the mitochondrial ND1 gene, the results of the present study showed B. dorsalis s.s. from different parts of China to have different genetic structures and origins. B. dorsalis s.s. in China and southeast Asia was found to have experienced rapid expansion in recent years. Data further support the existence of two distinguishable lineages of B. dorsalis s.s. in China and indicate genetic diversity and gene flow from multiple origins. The sequences in this paper have been deposited in GenBank/NCBI under accession numbers KC413034–KC413367. PMID:24655832

Critical analysis of the discrepancy between V(beta) and V(ss) for drugs exhibiting different two-compartment disposition profiles.

PubMed

Sobol, Eyal; Bialer, Meir

2005-03-01

It is well known that in the two-compartment open body model the values of apparent volume of distribution (V(beta)) and volume of distribution at steady state (V(ss)) are never identical. There are at least two conditions when V(beta) significantly overestimates V(ss). The first is when most of a drug is eliminated relatively rapidly but a small fraction of the dose persists and gives rise to an extremely long half-life. The second is when a drug is rapidly cleared from the central compartment with a short half-life. The primary purpose of the current paper was to investigate how different two-compartment disposition profiles affect the magnitude of difference between V(beta) and V(ss). Novel equations have been developed that relate the V(beta)/V(ss) ratio to f1 (fraction of drug elimination associated with the distributive phase) and to beta/alpha (ratio of the exponential coefficients). This paper demonstrates mathematically that an increasing value of f1 is associated with a greater divergence between V(beta) and V(ss). A similar relationship was also found for the divergence between the terminal half-life (t(1/2beta)) and the mean residence time (MRT). An increase in the beta/alpha ratio results in a substantial decrease of this discrepancy and provides a maximal possible value, or an upper limit to the V(beta)/V(ss) ratio. The newly derived equations along with their graphical presentation may serve as an excellent predictive tool for checking the accuracy of the experimentally obtained values of V(beta) and V(ss). Copyright 2004 John Wiley & Sons, Ltd.

Erosion and corrosion resistance of laser cladded AISI 420 stainless steel reinforced with VC

NASA Astrophysics Data System (ADS)

Zhang, Zhe; Yu, Ting; Kovacevic, Radovan

2017-07-01

Metal Matrix Composites (MMC) fabricated by the laser cladding process have been widely applied as protective coatings in industries to improve the wear, erosion, and corrosion resistance of components and prolong their service life. In this study, the AISI 420/VC metal matrix composites with different weight percentage (0 wt.%-40 wt.%) of Vanadium Carbide (VC) were fabricated on a mild steel A36 by a high power direct diode laser. An induction heater was used to preheat the substrate in order to avoid cracks during the cladding process. The effect of carbide content on the microstructure, elements distribution, phases, and microhardness was investigated in detail. The erosion resistance of the coatings was tested by using the abrasive waterjet (AWJ) cutting machine. The corrosion resistance of the coatings was studied utilizing potentiodynamic polarization. The results showed that the surface roughness and crack susceptibility of the laser cladded layer were increased with the increase in VC fraction. The volume fraction of the precipitated carbides was increased with the increase in the VC content. The phases of the coating without VC consisted of martensite and austenite. New phases such as precipitated VC, V8C7, M7C3, and M23C6 were formed when the primary VC was added. The microhardness of the clads was increased with the increase in VC. The erosion resistance of the cladded layer was improved after the introduction of VC. The erosion resistance was increased with the increase in the VC content. No obvious improvement of erosion resistance was observed when the VC fraction was above 30 wt.%. The corrosion resistance of the clads was decreased with the increase in the VC content, demonstrating the negative effect of VC on the corrosion resistance of AISI 420 stainless steel

Optimisation of a polygon mirror-based spectral filter for swept source optical coherence tomography (SS-OCT)

NASA Astrophysics Data System (ADS)

Everson, Michael; Duma, Virgil-Florin; Dobre, George

2018-03-01

Medical imaging using Optical Coherence Tomography (OCT) provides clinicians with 3D, high resolution reconstructions of microscopic structures, in depth. It has been initially developed for ophthalmology, in order to scan the retinas of patients to diagnose illness. The quality of the images depends upon their axial and lateral resolutions and the properties of the light being used. Research using a polygon mirror (PM) as a spectral filter in Swept Source OCT (SS-OCT) has resulted in a variety of different experimental arrangements. Although the application of PM-based SS-OCT sources has been successfully demonstrated, the combination of their components' fundamental properties and the overall impact they have on imaging performance is rarely reported. A more detailed examination of these properties would lead to a full description of their operation and to the best methods to employ if system performance is to be maximised. This work presents our current findings of on-going research into the optimisation of PM-based SS-OCT systems. A swept source spectral filter, consisting of a collimator, a transmission grating, a two-lens telescope and an off-axis PM with an end reflector mirror has been evaluated experimentally and compared with theoretical predictions. The system's performance has been compared for two different fibre collimators. Although the beam width on the grating is different for each of the two collimators, the spot size at the PM facet is made the same by selecting appropriate focal lengths. An improvement in the signal roll-off at the interferometer output of 1.0 dB/mm was obtained when using a 3.4 mm collimator compared to a 1.5 mm collimator.

Monitoring ssDNA Binding to the DnaB Helicase from Helicobacter pylori by Solid-State NMR Spectroscopy.

PubMed

Wiegand, Thomas; Cadalbert, Riccardo; Gardiennet, Carole; Timmins, Joanna; Terradot, Laurent; Böckmann, Anja; Meier, Beat H

2016-11-02

DnaB helicases are bacterial, ATP-driven enzymes that unwind double-stranded DNA during DNA replication. Herein, we study the sequential binding of the "non-hydrolysable" ATP analogue AMP-PNP and of single-stranded (ss) DNA to the dodecameric DnaB helicase from Helicobacter pylori using solid-state NMR. Phosphorus cross-polarization experiments monitor the binding of AMP-PNP and DNA to the helicase. 13 C chemical-shift perturbations (CSPs) are used to detect conformational changes in the protein upon binding. The helicase switches upon AMP-PNP addition into a conformation apt for ssDNA binding, and AMP-PNP is hydrolyzed and released upon binding of ssDNA. Our study sheds light on the conformational changes which are triggered by the interaction with AMP-PNP and are needed for ssDNA binding of H. pylori DnaB in vitro. They also demonstrate the level of detail solid-state NMR can provide for the characterization of protein-DNA interactions and the interplay with ATP or its analogues. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electromagnetic nondestructive evaluation of tempering process in AISI D2 tool steel

NASA Astrophysics Data System (ADS)

Kahrobaee, Saeed; Kashefi, Mehrdad

2015-05-01

The present paper investigates the potential of using eddy current technique as a reliable nondestructive tool to detect microstructural changes during the different stages of tempering treatment in AISI D2 tool steel. Five stages occur in tempering of the steel: precipitation of ɛ carbides, formation of cementite, retained austenite decomposition, secondary hardening effect and spheroidization of carbides. These stages were characterized by destructive methods, including dilatometry, differential scanning calorimetry, X-ray diffraction, scanning electron microscopic observations, and hardness measurements. The microstructural changes alter the electrical resistivity/magnetic saturation, which, in turn, influence the eddy current signals. Two EC parameters, induced voltage sensed by pickup coil and impedance point detected by excitation coil, were evaluated as a function of tempering temperature to characterize the microstructural features, nondestructively. The study revealed that a good correlation exists between the EC parameters and the microstructural changes.

Long-range effect in nitrogen ion-implanted AISI 316L stainless steel

NASA Astrophysics Data System (ADS)

Budzynski, P.

2015-01-01

The effect of nitrogen ion implantation on AISI 316L stainless steel was investigated. The microstructure and composition of an N implanted layer were studied by RBS, GIXRD, SEM, and EDX measurements. Friction and wear tests were also performed. The discrepancy between the measured and calculated stopped ion maximum range does not exceed 0.03 μm. After nitrogen implantation with a fluence of 5 × 1017 ion/cm2, additional phases of expanded austenite were detected. At a 5-fold larger depth than the maximum ion range, improvement in the coefficient of friction and wear was detected. We have shown, for the first time, the long-range effect in tribological investigations. The long-range effect is caused by movement of not only defects along the depth of the sample, as assumed so far, but also nitrogen atoms.

Silver syndrome variant of hereditary spastic paraplegia: A locus to 4p and allelism with SPG4.

PubMed

Orlacchio, A; Patrono, C; Gaudiello, F; Rocchi, C; Moschella, V; Floris, R; Bernardi, G; Kawarai, T

2008-05-20

To perform a clinical and genetic study of two large Italian families (RM-36 and RM-51) showing the cardinal clinical features of Silver syndrome (SS), a rare dominantly inherited form of hereditary spastic paraplegia (HSP) complicated by amyotrophy of the small hand muscles. Clinical assessment including neurophysiologic, neuropsychological, and neuroimaging evaluations. Genetic studies included linkage and sequence analyses. Using a genome-wide survey in the RM-36 family, a novel locus (SPG38) has been identified and mapped within the 13.1-cM region on chromosome 4p16-p15 between markers D4S432 and D4S1599. The RM-51 family was linked to the SPG4 locus at 2p21-p24 and sequence analysis of SPG4 showed a novel frameshift mutation p.Asp321GlyfsX6. Clinical examination of the affected members carrying the mutation showed high frequency of additional clinical features including decreased vibration sense, pes cavus, temporal lobe epilepsy, and cognitive impairment. This study demonstrates evidence of a novel locus SPG38 for Silver syndrome (SS) and suggests that genetic defects in SPG4 might lead to broad clinical features overlapped with those of SS.

Double heterozygous mutations Gln100Leu and His348Gln of the F7 gene in a patient with factor VII deficiency.

PubMed

Li, Min; Zheng, Fangxiu; Jin, Yanhui; Wang, Mingshan; Zhu, Liqing; Yang, Lihong

2013-03-01

A 25-year-old Chinese woman who had a history of easy bruising was admitted to hospital due to uncontrolled epistaxis. She showed factor VII activity level of 2% and factor VII antigen level of 4% of the normal value. We detected a novel missense mutation g.8355 A>T (p.Gln100Leu) in the second epidermal growth factor-like (EGF) domain and a g.11482 T>G (p.His348Gln) in the catalytic domain. Although the Gln100 residue is close to the junction of EGF-2 domain with the serine protease domain, we infer that the substitution of polar negatively charged Gln residue at the position 100 with introduction of nonpolar Leu residue may be likely to perturb proper folding, resulting in decreasing factor VII activity.

Investigating early stages of biocorrosion with XPS: AISI 304 stainless steel exposed to Burkholderia species

NASA Astrophysics Data System (ADS)

Johansson, Leena-Sisko; Saastamoinen, Tuomas

1999-04-01

We have investigated the interactions of an exopolymer-producing bacteria, Burkholderia sp. with polished AISI 304 stainless steel substrates using X-ray photoelectron spectroscopy (XPS). Steel coupons were exposed to the pure bacteria culture in a specially designed flowcell for 6 h during which the experiment was monitored in situ with an optical microscope. XPS results verified the formation of biofilm containing extracellular polymer on all the samples exposed to bacteria. Sputter results indicated that some ions needed for metabolic processes were trapped within the biofilm. Changes in the relative Fe concentration and Fe 2p peak shape indicated that also iron had accumulated into the biofilm.

Development in corrosion resistance by microstructural refinement in Zr-16 SS 304 alloy using suction casting technique

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

Das, N., E-mail: nirupamd@barc.gov.in; Sengupta, P.; Abraham, G.

Highlights: • Grain refinement was made in Zr–16 wt.% SS alloy while prepared by suction casting process. • Distribution of Laves phase, e.g., Zr{sub 2}(Fe, Cr) was raised in suction cast (SC) Zr–16 wt.% SS. • Corrosion resistance was improved in SC alloy compared to that of arc-melt-cast alloy. • Grain refinement in SC alloy assisted for an increase in its corrosion resistance. - Abstract: Zirconium (Zr)-stainless steel (SS) hybrid alloys are being considered as baseline alloys for developing metallic-waste-form (MWF) with the motivation of disposing of Zr and SS base nuclear metallic wastes. Zr–16 wt.% SS, a MWF alloymore » optimized from previous studies, exhibit significant grain refinement and changes in phase assemblages (soft phase: Zr{sub 2}(Fe, Cr)/α-Zr vs. hard phase: Zr{sub 3}(Fe, Ni)) when prepared by suction casting (SC) technique in comparison to arc-cast-melt (AMC) route. Variation in Cr-distribution among different phases are found to be low in suction cast alloy, which along with grain refinement restricted Cr-depletion at the Zr{sub 2}(Fe, Cr)/Zr interfaces, prone to localized attack. Hence, SC alloy, compared to AMC alloy, showed lower current density, higher potential at the breakdown of passivity and higher corrosion potential during polarization experiments (carried out under possible geological repository environments, viz., pH 8, 5 and 1) indicating its superior corrosion resistance.« less

Understanding heat and fluid flow in linear GTA welds

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

Zacharia, T.; David, S.A.; Vitek, J.M.

1992-01-01

A transient heat flow and fluid flow model was used to predict the development of gas tungsten arc (GTA) weld pools in 1.5 mm thick AISI 304 SS. The welding parameters were chosen so as to correspond to an earlier experimental study which produced high-resolution surface temperature maps. The motivation of the present study was to verify the predictive capability of the computational model. Comparison of the numerical predictions and experimental observations indicate good agreement.

Understanding heat and fluid flow in linear GTA welds

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

Zacharia, T.; David, S.A.; Vitek, J.M.

1992-12-31

A transient heat flow and fluid flow model was used to predict the development of gas tungsten arc (GTA) weld pools in 1.5 mm thick AISI 304 SS. The welding parameters were chosen so as to correspond to an earlier experimental study which produced high-resolution surface temperature maps. The motivation of the present study was to verify the predictive capability of the computational model. Comparison of the numerical predictions and experimental observations indicate good agreement.

Preparation of SS316L MIM feedstock with biopolymer as a binder

NASA Astrophysics Data System (ADS)

Abdullah, A. A.; Norita, H.; Azlina, H. N.; Sulong, A. B.; Mas'ood, N. N.

2018-01-01

This paper focus on feedstock preparation for SS316L metal injection molding (MIM) part. The primary step of feedstock preparation, critical powder loading determined by two method; maximum filled volume calculation model and torque analysis. The critical powder loading determined by calculation was 70 vol% to 77 vol% while for experimental approaches shows the value of 75 vol%. The feedstock was prepared by mixing SS316L powder and polymer binder with ratio 70:30 at 175 °C with speed of 50 rpm. The feedstock was analyzed by thermogravimetric analysis (TGA) and Scanning electron microscope (SEM). The composition for the feedstock after preparation step was confirmed by TGA. It was found that the prepared feedstock component was compatible to each other and composition is maintain along the mixing step.

Hot compression deformation behavior of AISI 321 austenitic stainless steel

NASA Astrophysics Data System (ADS)

Haj, Mehdi; Mansouri, Hojjatollah; Vafaei, Reza; Ebrahimi, Golam Reza; Kanani, Ali

2013-06-01

The hot compression behavior of AISI 321 austenitic stainless steel was studied at the temperatures of 950-1100°C and the strain rates of 0.01-1 s-1 using a Baehr DIL-805 deformation dilatometer. The hot deformation equations and the relationship between hot deformation parameters were obtained. It is found that strain rate and deformation temperature significantly influence the flow stress behavior of the steel. The work hardening rate and the peak value of flow stress increase with the decrease of deformation temperature and the increase of strain rate. In addition, the activation energy of deformation ( Q) is calculated as 433.343 kJ/mol. The microstructural evolution during deformation indicates that, at the temperature of 950°C and the strain rate of 0.01 s-1, small circle-like precipitates form along grain boundaries; but at the temperatures above 950°C, the dissolution of such precipitates occurs. Energy-dispersive X-ray analyses indicate that the precipitates are complex carbides of Cr, Fe, Mn, Ni, and Ti.

G-quadruplex and G-rich sequence stimulate Pif1p-catalyzed downstream duplex DNA unwinding through reducing waiting time at ss/dsDNA junction

PubMed Central

Zhang, Bo; Wu, Wen-Qiang; Liu, Na-Nv; Duan, Xiao-Lei; Li, Ming; Dou, Shuo-Xing; Hou, Xi-Miao; Xi, Xu-Guang

2016-01-01

Alternative DNA structures that deviate from B-form double-stranded DNA such as G-quadruplex (G4) DNA can be formed by G-rich sequences that are widely distributed throughout the human genome. We have previously shown that Pif1p not only unfolds G4, but also unwinds the downstream duplex DNA in a G4-stimulated manner. In the present study, we further characterized the G4-stimulated duplex DNA unwinding phenomenon by means of single-molecule fluorescence resonance energy transfer. It was found that Pif1p did not unwind the partial duplex DNA immediately after unfolding the upstream G4 structure, but rather, it would dwell at the ss/dsDNA junction with a ‘waiting time’. Further studies revealed that the waiting time was in fact related to a protein dimerization process that was sensitive to ssDNA sequence and would become rapid if the sequence is G-rich. Furthermore, we identified that the G-rich sequence, as the G4 structure, equally stimulates duplex DNA unwinding. The present work sheds new light on the molecular mechanism by which G4-unwinding helicase Pif1p resolves physiological G4/duplex DNA structures in cells. PMID:27471032

Differential roles of SS18-SSX fusion gene and insulin-like growth factor-1 receptor in synovial sarcoma cell growth

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

Toernkvist, Maria; Natalishvili, Natalia; Xie Yuntao

2008-04-11

Recently we demonstrated that the synovial sarcoma specific fusion gene SS18-SSX is crucial for cyclin D1 expression and is linked to cell proliferation. In this report we explore the role of SS18-SSX and IGF-1R for their potential functions in cellular proliferation and survival in cultured synovial sarcoma cells. We found that targeting of SS18-SSX mRNA by antisense oligonucleotide treatment drastically and rapidly decreased cell proliferation but caused only a slight increase of apoptosis. The synovial sarcoma cells were confirmed to express IGF-1R, and treatment with an IGF-1R inhibitor resulted in substantially reduced cell viability by inducing apoptosis in these cells.more » Conversely, inhibition of the IGF-1R resulted only in a slight to moderate decrease in DNA synthesis. In conclusion, SS18-SSX and IGF-1R seem to play important but different roles in maintaining malignant growth of synovial sarcoma cells. Whereas SS18-SSX maintains cyclin D1 and cell proliferation, IGF-1R protects from apoptosis.« less

Reduction-responsive PEtOz-SS-PCL micelle with tailored size to overcome blood-brain barrier and enhance doxorubicin antiglioma effect.

PubMed

Li, Yuling; Baiyang, Li; Leran, Bu; Zhen, Wang; Yandong, Xie; Baixiang, Du; Dandan, Zhu; Yufu, Zhu; Jun, Liang; Rutong, Yu; Hongmei, Liu

2017-11-01

A series of novel reduction-responsive micelles with tailored size were designed and prepared to release doxorubicin (DOX) for treating glioma, which were developed based on amphiphilic block copolymer poly (2-ethyl-2-oxazoline)-b-poly (ε-caprolactone) (PEtOz-SS-PCL) and the micelle size could be regulated by designing the polymer structure. The DOX-loaded PEtOz-SS-PCL micelles had small size and rapid drug release in reductive intracellular environments. Biodistribution and in vivo imaging studies in C6 glioma mice tumor model showed that DOX loaded PEtOz-SS-PCL43 micelles with the smallest size had superior accumulation and fast drug release in tumor sites. In vivo antitumor activity demonstrated that DOX-loaded PEtOz-SS-PCL43 micelles improved antitumor efficacy in contrast to PEtOz-SS-PCL micelles with larger size toward the orthotopic C6-Luci cells-bearing mice. This study shows great potential in tailoring the micelle size and introducing the responsive bonds or compartment for intracellular drug delivery and release in glioma treatment by designing the architecture of the polymer.

Effects of Deep Cryogenic Treatment on the Wear Resistance and Mechanical Properties of AISI H13 Hot-Work Tool Steel

NASA Astrophysics Data System (ADS)

Çiçek, Adem; Kara, Fuat; Kıvak, Turgay; Ekici, Ergün; Uygur, İlyas

2015-11-01

In this study, a number of wear and tensile tests were performed to elucidate the effects of deep cryogenic treatment on the wear behavior and mechanical properties (hardness and tensile strength) of AISI H13 tool steel. In accordance with this purpose, three different heat treatments (conventional heat treatment (CHT), deep cryogenic treatment (DCT), and deep cryogenic treatment and tempering (DCTT)) were applied to tool steel samples. DCT and DCTT samples were held in nitrogen gas at -145 °C for 24 h. Wear tests were conducted on a dry pin-on-disk device using two loads of 60 and 80 N, two sliding velocities of 0.8 and 1 m/s, and a wear distance of 1000 m. All test results showed that DCT improved the adhesive wear resistance and mechanical properties of AISI H13 steel. The formation of small-sized and uniformly distributed carbide particles and the transformation of retained austenite to martensite played an important role in the improvements in the wear resistance and mechanical properties. After cleavage fracture, the surfaces of all samples were characterized by the cracking of primary carbides, while the DCT and DCTT samples displayed microvoid formation by decohesion of the fine carbides precipitated during the cryo-tempering process.

Mitochondria-targeted molecules MitoQ and SS31 reduce mutant huntingtin-induced mitochondrial toxicity and synaptic damage in Huntington's disease

PubMed Central

Yin, Xiangling; Manczak, Maria; Reddy, P. Hemachandra

2016-01-01

The objective of this study was to determine the protective effects of the mitochondria-targeted molecules MitoQ and SS31 in striatal neurons that stably express mutant huntingtin (Htt) (STHDhQ111/Q111) in Huntington's disease (HD). We studied mitochondrial and synaptic activities by measuring mRNA and the protein levels of mitochondrial and synaptic genes, mitochondrial function, and ultra-structural changes in MitoQ- and SS31-treated mutant Htt neurons relative to untreated mutant Htt neurons. We used gene expression analysis, biochemical methods, transmission electron microscopy (TEM) and confocal microscopy methods. In the MitoQ- and SS31-treated mutant Htt neurons, fission genes Drp1 and Fis1 were down-regulated, and fusion genes Mfn1, Mfn2 and Opa1 were up-regulated relative to untreated neurons, suggesting that mitochondria-targeted molecules reduce fission activity. Interestingly, the mitochondrial biogenesis genes PGC1α, PGC1β, Nrf1, Nrf2 and TFAM were up-regulated in MitoQ- and SS31-treated mutant Htt neurons. The synaptic genes synaptophysin and PSD95 were up-regulated, and mitochondrial function was normal in the MitoQ- and SS31-treated mutant Htt neurons. Immunoblotting findings of mitochondrial and synaptic proteins agreed with the mRNA findings. TEM studies revealed decreased numbers of structurally intact mitochondria in MitoQ- and SS31-treated mutant Htt neurons. These findings suggest that mitochondria-targeted molecules MitoQ and SS31 are protective against mutant Htt-induced mitochondrial and synaptic damage in HD neurons, and these mitochondria-targeted molecules are potential therapeutic molecules for the treatment of HD neurons. PMID:26908605

Seismic Anisotropy in Mantle Transition Zone: Constraints from Observations and Synthetic Modeling of SS Precursors

NASA Astrophysics Data System (ADS)

Huang, Q.; Schmerr, N. C.; Waszek, L.; Beghein, C.; Weidner, E. C.

2017-12-01

Mantle transition zone (MTZ) is delineated by the 410 and 660 km discontinuities and plays an important role in mantle convection. Mineral physics experiments predict that wadsleyite and ringwoodite can have 13% and 2% single-crystal anisotropy respectively, indicating that seismic anisotropy is likely to exist in the upper part of the MTZ when MTZ minerals are aligned by mantle flow (e.g. subducting slabs). Here we use the SS precursors to study the topography change and seismic anisotropy in the vicinity of MTZ discontinuities. An up-to-date SS precursor dataset consisting of 45,624 records was collected to investigate MTZ topography and anisotropy. We stacked the whole dataset into 9 geographical caps to obtain the global topography of 410 and 660 km discontinuities. The MTZ is thickened by 15 km beneath subduction zones (e.g. Japan and South America) and also thinned by 15 km beneath mantle plume regions (e.g. Bowie and Iceland hotspots), which is consistent with thermal heterogeneity in the mid-mantle. We identify four locations with sufficient bounce point density and azimuthal coverage of SS precursors to study azimuthal anisotropy in MTZ; the central Pacific, the northwest Pacific, Greenland and the central Atlantic. We stack the data by the azimuth of SS bounce points falling within the range of 2000 km in these four locations. The goal is to detect the azimuthal dependence of travel time and amplitude of SS precursors, thus to constrain azimuthal anisotropy in MTZ. The central Pacific bin has fast direction at 110° for both S410S and S660S azimuthal stacks, which is interpreted as seismic anisotropy in the overlying upper mantle. We also stack data in subduction zones by the relative azimuths of bounce points compared to mantle flow directions to test the hypothesis that subducting slabs can cause azimuthal anisotropy in MTZ. A trench-parallel fast direction is observed for both S410S and S660S travel times and amplitudes, but not for their differential

[Studies on purification and properties of antagonistic protein from bacteria SS02 of Paenibacillus daejeonensis].

PubMed

Zhu, Kai; Zhang, Xiao-Yu; Ren, Zhi; Feng, Ding-Sheng; Wang, Yi-Ding

2007-07-01

The antifungal, anti-bacterical, anti-brine shrimp activities of SD22 isolated from Paenibacillus daejeonensis Bacteria SS02 were studied. The separation steps included ultracentrifugation, ultrafiltration and (NH4)2SO4 fractional precipitation, further purification was performed by SephadexG-75 and DEAE-32 chromatography. Its molecular weight determined by SDS-PAGE was 56.0 kD and its isoelectfic point was 6.4. SD22 was thermostable to some extent and stable to ultraviolet, but sensitive to some of the enzyme. SD22 could kill most pathogens from propagation, such as Rhizoctonia cerealis, Sclerotinia sclerotiorum Physalospora piricala, Trichodema viride, Gliocladium viride, Curvularia leaf spot, Fusarium sp, Fusarium head blight, Beauveria Bassiana, Escherichia coli, Staphylococcus aureus, Bacillus subtilis , Candidal vaginitis, Fusarium oxysporum Schl. emend. Sayder & Hansem et al. The results will be helpful to find out a novel antifungal protein.

Social class and survival on the S.S. Titanic.