Sample records for ukladu fojazyt-tlenek galu
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Islam, S; Oh, H; Jalal, S; Karpati, F; Ciofu, O; Høiby, N; Wretlind, B
2009-01-01
In total, 40 Pseudomonas aeruginosa isolates from cystic fibrosis (CF) patients were included in this study. Twenty of these were collected in 1994 and 1997, from six CF patients, and the rest were collected from different CF patients in 2000 and 2001. The relative expression of mRNA for the efflux pump protein MexY was determined by real-time PCR and correlated with susceptibilities to amikacin and tobramycin. The chromosomal genes mexZ, rplY, galU, PA5471 and nuoG, which were found to have a role in the gradual increase in MICs of aminoglycoside antibiotics in laboratory mutants of P. aeruginosa, were analysed. MexY mRNA overproduction was found in 17/20 isolates collected in 1994 and 1997, and was correlated with decreased susceptibility to aminoglycosides. Alteration of the MexXY-OprM efflux system has been the main mechanism of resistance to aminoglycoside antibiotics in CF P. aeruginosa isolates over the 3-year period. In several isolates, expression of the PA5471 gene product might have some effect on elevated MICs of aminoglycosides. Inactivation of rplY, galU and/or nuoG may explain the gradual increase in MICs of aminoglycosides in laboratory mutants but probably not in the CF environment, as rplY and galU were unaltered in all isolates, and nuoG was not expressed in only one isolate. No 16S rRNA A-site mutations were found in any of the four copies of the gene in 13 investigated isolates.
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1992-01-01
In First Out FMEA Failure Mode Effects Analysis EDM Engineering Development Model GALU Generic Arithmetic Logic Unit GaAs Gallium Arsenide GTE Ground...Bl B>55 * 1585/IS1/B1 = B56 I$11146/I$3/B1 B= 57 I$2S146/I$2/B1 B= 58 * $1146/1$1/81 =>B59 * 1590/IS3/Bl B= 60 *1$590/IS2/Bl== B61 * 1590/IS1/B1 - B62...vote circuitry. It is known that only 60 fC of charge is needed to upset the latch elements. It is interesting to speculate how much charge is required
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Pandey, Ramesh Prasad; Parajuli, Prakash; Gurung, Rit Bahadur; Sohng, Jae Kyung
2016-09-01
Escherichia coli BL21 (DE3) was engineered by blocking glucose-1-phosphate utilizing glucose phosphate isomerase (pgi), glucose-6-phosphate dehydrogenase (zwf) and uridylyltransferase (galU) genes to produce pool of four different rare dTDP-sugars. The cytosolic pool of dTDP-l-rhamnose, dTDP-d-viosamine, dTDP-4-amino 4,6-dideoxy-d-galactose, and dTDP-3-amino 3,6-dideoxy-d-galactose was generated by overexpressing respective dTDP-sugars biosynthesis genes from various microbial sources. A flexible glycosyltransferase YjiC, from Bacillus licheniformis DSM 13 was also overexpressed to transfer sugar moieties to 3-hydroxyl group of 3-hydroxyflavone, a core unit of flavonoids. Among four rare dTDP-sugars generated in cytosol of engineered strains, YjiC solely transferred l-rhamnose from dTDP-l-rhamnose and tuned to rhamnosyltransferase. Copyright © 2016. Published by Elsevier Inc.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Rod, M.L. Alam, K.Y.; Cunningham, P.R.; Clark, D.P.
When grown at high osmotic pressure, some strains of Escherichia coli K-12 synthesized substantial levels of free sugar and accumulated proline if it was present in the growth medium. The sugar was identified as trehalose. Strains of E. coli K-12 could be divided into two major classes with respect of osmoregulation. Those of class A showed a large increase in trehalose levels with increasing medium osmolarity and also accumulated proline from the medium, whereas those in class B showed no accumulation of trehalose or proline. Most class A strains carried suppressor mutations which arose during their derivation from the wildmore » type, whereas the osmodefective strains of class B were suppressor free. When amber suppressor mutations at the supD, supE, or supF loci were introduced into such sup{sup o} osmodefective strains, they became osmotolerant and gained the ability to accumulate trehalose in response to elevated medium osmolarity. It appears that the original K-12 strain of E. coli carries an amber mutation in a gene affecting osmoregulation. Mutants lacking ADP-glucose synthetase (glgC) accumulated trehalose normally, whereas mutants lacking UDP-glucose synthetase (galU) did not make trehalose and grew poorly in medium of high osmolarity. Trehalose synthesis was repressed by exogenous glycine betaine but not by proline.« less
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NASA Astrophysics Data System (ADS)
Aftabi, Alijan; Atapour, Habibeh
2018-10-01
There exist few data on the geochemical signatures and occurrence of silica-rich coatings developed on siliceous carbonate substrates. The rock coatings in the Maran-e-Galu area in southeast-central Iran are composed of four layers; a lower thick layer (1 mm) of silica, a lower thin film of Fe-Mn oxide, an upper thick (1 mm) silica-rich layer, and an upper thin film of Fe-Mn oxide. Energy dispersive X-ray spectrometer (EDS), X-ray diffraction and bulk coating geochemistry data obtained by XRF and ICP-MS highlight that the 1-3 mm thick silica-rich coatings occur as a silica glaze of opal composition on the siliceous carbonate substrate. The coatings were probably formed by the interaction of rainfall, water vapor or dew with silicate and carbonate-rich detrital atmospheric dust, releasing H4SiO4with a pH of 5-10 in this semiarid-arid desert environment. This led to the formation of silica gels as well as minor Fe-Mn oxide gels by evaporation and supersaturation, and finally changed to the black brown silica glaze probably at ambient temperatures of >40 °C Major and minor element signatures are consistent with the known silica glazes, displaying enrichment in Ba, Sr, P, and LREEs with little to no Eu and Ce anomalies and a weak Tm anomaly. However, the very low content of aluminum oxide is well correlated with the known classified silica glaze of genetic type 1, reflecting the absence of detrital clay minerals. The low Fe and Mn contents in bulk coatings (3.6 and 10 magnitudes lower than crustal abundance, respectively) and lack of biochemical processes in the atmospheric dust highlight the semiarid-arid climate setting. We thereby conclude that a new variant of silica glaze of 1-3 mm thickness could form on siliceous carbonate substrates under an alkaline pH in semiarid-arid regions.
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Wu, Rina; Wang, Weiwei; Yu, Dongliang; Zhang, Wenyi; Li, Yan; Sun, Zhihong; Wu, Junrui; Meng, He; Zhang, Heping
2009-01-01
Lactobacillus casei Zhang, isolated from traditional home-made koumiss in Inner Mongolia of China, was considered as a new probiotic bacterium by probiotic selection tests. We carried out a proteomics study to identify and characterize proteins expressed by L. casei Zhang in the exponential phase and stationary phase. Cytosolic proteins of the strain cultivated in de Man, Rogosa, and Sharpe broth were resolved by two-dimensional gel electrophoresis using pH 4–7 linear gradients. The number of protein spots quantified from the gels was 487 ± 21 (exponential phase) and 494 ± 13 (stationary phase) among which a total of 131 spots were identified by MALDI-TOF/MS and/or MALDI-TOF/TOF according to significant growth phase-related differences or high expression intensity proteins. Accompanied by the cluster of orthologous groups (COG), codon adaptation index (CAI), and GRAVY value analysis, the study provided a very first insight into the profile of protein expression as a reference map of L. casei. Forty-seven spots were also found in the study that showed statistically significant differences between exponential phase and stationary phase. Thirty-three of the spots increased at least 2.5-fold in the stationary phase in comparison with the exponential phase, including 19 protein spots (e.g. Hsp20, DnaK, GroEL, LuxS, pyruvate kinase, and GalU) whose intensity up-shifted above 3.0-fold. Transcriptional profiles were conducted to confirm several important differentially expressed proteins by using real time quantitative PCR. The analysis suggests that the differentially expressed proteins were mainly categorized as stress response proteins and key components of central and intermediary metabolism, indicating that these proteins might play a potential important role for the adaptation to the surroundings, especially the accumulation of lactic acid in the course of growth, and the physiological processes in bacteria cell. PMID:19508964
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The Influence of Shale Rock Fracturing Equipment Operation on Atmospheric Air Quality
NASA Astrophysics Data System (ADS)
Bogacki, Marek; Macuda, Jan
2014-12-01
The hydraulic fracturing jobs performed on shale rocks are connected with atmospheric emissions of dusts and exhaust gases from high-power motors supplying pump aggregates used for fracturing operations and from other technological devices. The total power of motors driving technological systems depends on the specific character of deposit and well and may range between a dozen to tens of thousands kW. An exemplary set of technological systems used for frac jobs is presented in figure 1. The following substances are emitted to the atmosphere during engine operation, e.g. nitrogen oxides (NOx), sulfur dioxide (SO2), carbon oxide (CO), dust PM10, ammonia, benzo(a)pyrene (B(a)P), benzene, toluene, xylene, formaldehyde, acetaldehyde, acrolein. As a consequence admissible concentrations of these substances in air can be exceeded. The influence of dust and gaseous emissions accompanying shale rock fracturing jobs is addressed in this paper. Model analyses were performed. An exemplary model of a process used for simulating propagation of atmospheric emissions in a specified calculation area (1,150 m × 1,150 m) were based on the analysis of hydraulic fracturing jobs performed in wells in Poland and abroad. For making calculations more actual, the model was located in the Gdańsk area and was ascribed its typical meteorological and orographic parameters. In the center of this area a rig site 150 m x 150 m was distinguished. The emission field was generated by 12 high-power engines supplying pump aggregates, 1680 kW each. The time of work of particular engines was established for 52 hrs (13 frac jobs, each lasting 4 hrs). It was assumed that all engines will operate simultaneously and using 100% of their power. Attention was paid to the correct modelling of the real emission field. Technical parameters of motors and the applied fuels were characterized. Emission indices were worked out by, e.g. U.S. Environmental Protection Agency or European Environment Agency. The calculations of air pollutions from analyzed motors were performed with a mathematical modelling method using Gaussian plum. The results of calculations could be used for evaluating spatial distribution of maximum 1 hour concentrations (S1), incidence of exceeding admissible 1 hour concentration values (P(D1)), percentile 99.8 or 99.726 from 1 hour concentrations and average concentrations (Sa) for selected most important for the air quality contaminants, i.e. NOx (as NO2), SO2, CO, PM10, benzo(a)pyrene, benzene, toluene, xylene, formaldehyde, acetaldehyde and acrolein. The results of calculated air concentrations of selected substances on the rig border are listed in table 9, whereas spatial distributions of NOx and PM10 concentrations in figures 3 to 8. The analysis of the obtained results did not reveal cases of exceeding Polish emission standards. However, nitrogen oxide (NOx) or dust PM10 can be expected to exceed these values, e.g. in a situation when the total power installed in motors driving technological systems in the course of hydraulic fracking will be higher than assumed in the analyses. The results of calculations show to a significant impact of nitrogen oxides (NOx) and dust PM10 emissions on air quality. The risk that emission standards are exceeded beyond the rig area is conditioned both by technological factors (total power of operating motors, parameters of combusted fuel, reduced emission technologies applied to engines, duration of frac jobs, etc.) and a number of external factors, e.g. meteorological and orographic factors or high level of emitted substances in air within the rig area. Proces hydraulicznego szczelinowania skał łupkowych wiąże się z emisją do powietrza zanieczyszczeń pyłowo-gazowych z silników wysokoprężnych dużej mocy napędzających agregaty pompowe do szczelinowania skał oraz inne urządzenia technologiczne. Łączna moc silników napędzających urządzenia technologiczne uzależniona jest od specyfiki złoża oraz specyfiki odwiertu i waha się od kilkunastu do kilkudziesięciu tysięcy kW. Przykładowy zestaw urządzeń technologicznych wykorzystywanych w procesie szczelinowania zamieszczono na rysunku 1. Podczas pracy silników do atmosfery emitowane są między innymi następujące substancje: tlenki azotu (NOx), ditlenek siarki (SO2), tlenek węgla (CO), pył PM10, amoniak, benzo(a)piren (B(a)P), benzen, toluen, ksylen, formaldehyd, acetaldehyd, akroleina. Skutkiem emisji mogą być przekroczenia dopuszczalnych, określonych prawem wartości stężeń substancji w powietrzu. W artykule skoncentrowano się na ocenie wpływu na jakość powietrza atmosferycznego emisji substancji pyłowo-gazowych towarzyszących procesowi szczelinowania skał łupkowych. Badania miały charakter modelowy. W oparciu o analizę przebiegu szeregu procesów szczelinowania hydraulicznego wykonywanych na wiertniach zlokalizowanych w Polsce i za granicą zbudowano przykładowy model procesu, który posłużył do wykonania symulacji propagacji zanieczyszczeń emitowanych substancji w powietrzu w zadeklarowanym obszarze obliczeniowym stanowiącym teren o wymiarach 1150 m × 1150 m. Dla urealnienia wyników obliczeń umiejscowiono model badanego obszaru w okolicach Gdańska i przypisano mu charakterystyczne dla tego rejonu parametry meteorologiczne i orograficzne. W środku analizowanego obszaru zlokalizowano teren wiertni o wymiarach 150 m x 150 m. Pole emisji kształtowane było przez 12 silników wysokoprężnych napędzających agregaty pompowe, każdy o mocy 1680 kW. Czas pracy pojedynczego silnika ustalono na 52 godziny w roku (13 zabiegów szczelinowania, każdy trwający 4 godziny). W obliczeniach założono, że podczas trwania szczelinowania wszystkie silniki będą pracowały równocześnie i będą obciążone w 100 %. W artykule dużo uwagi poświęcono poprawnemu zamodelowaniu rzeczywistego pola emisji. Scharakteryzowano parametry techniczne silników oraz zużywanych przez nie paliw. Zaadoptowano na potrzeby obliczeń modelowych wskaźniki emisji opracowane między innymi przez Amerykańską Agencję ds. Środowiska, czy Europejską Agencję ds. Środowiska. Obliczenia propagacji w powietrzu zanieczyszczeń pochodzących z analizowanych silników wykonano metodą modelowania matematycznego wykorzystując w tym celu model smugi Gaussa. Wyniki obliczeń pozwoliły na ocenę rozkładu przestrzennego stężeń maksymalnych 1-godzinnych (S1), częstości przekroczeń wartości dopuszczalnej stężeń 1-godzinnych (P(D1)), percentyla 99,8 lub 99,726 ze stężeń 1-godzinnych oraz stężeń średniorocznych (Sa) dla wybranych, najbardziej istotnych z punktu widzenia wpływu na jakość powietrza zanieczyszczeń tj.: NOx (jako NO2), SO2, CO, PM10, benzo(a) pirenu, benzenu, toluenu, ksylenu, formaldehydu, aldehydu octowego oraz akroleiny. Wyniki obliczeń stężeń wybranych substancji w powietrzu na granicy wiertni zestawiono w tabeli 9, natomiast rozkłady przestrzenne stężeń NOx oraz PM10 przedstawiono na rysunkach 3-8. Analiza wyników obliczeń nie wykazała wprawdzie dla analizowanego przypadku występowania przekroczeń obowiązujących w Polsce standardów imisyjnych, ale w przypadku takich zanieczyszczeń jak tlenki azotu (NOx) czy pył PM10 istnieje realne zagrożenie wystąpienia takich przekroczeń, między innymi w sytuacji, gdy łączna moc zainstalowana w silnikach napędzających urządzenia technologiczne w czasie procesu szczelinowania będzie wyraźnie większa niż przyjęta w opisanych badaniach. Wnioski z przeprowadzonych obliczeń wskazują na istotny wpływ na jakość powietrza emisji tlenków azotu (NOx) i pyłu PM10. Ryzyko wystąpienia przekroczeń obowiązujących standardów imisyjnych poza granicą wiertni jest uwarunkowane zarówno czynnikami technologicznymi (łączna moc pracujących silników, parametry spalanego paliwa, zastosowane w silnikach techniki ograniczenia emisji, czas trwania szczelinowania itp.) jak i szeregiem czynników zewnętrznych takich jak czynniki meteorologiczne, orograficzne czy wysoki poziom tła emitowanych substancji w powietrzu w lokalizacji wiertni.