Chemical dispersants can be a useful tool to mitigate oil spills. This study examined potential risks to sensitive estuarine species by comparing the toxicity of two dispersants (Corexit
®
EC9500A ...and Finasol
®
OSR 52) individually and in chemically enhanced water-accommodated fractions (CEWAFs) of Louisiana Sweet Crude oil. Acute toxicity thresholds and sublethal biomarker responses were determined in seven species (sheepshead minnow, grass shrimp, mysid, amphipod, polychaete, hard clam, mud snail). Comparing median lethal (LC
50
) values for the dispersants, Finasol was generally more toxic than Corexit and had greater sublethal toxicity (impaired embryonic hatching, increased lipid peroxidation, decreased acetylcholinesterase activity). The nominal concentration-based mean LC
50
for all species tested with Corexit was 150.31 mg/L compared with 43.27 mg/L with Finasol. Comparing the toxicity of the CEWAFs using the nominal concentrations (% CEWAF), Corexit-CEWAFs appeared more toxic than Finasol-CEWAFs; however, when LC
50
values were calculated using measured hydrocarbon concentrations, the Finasol-CEWAFs were more toxic. There was greater dispersion efficiency leading to greater hydrocarbon concentrations measured in the Corexit-CEWAF solutions than in equivalent Finasol-CEWAF solutions. The measured concentration-based mean LC
50
values for all species tested with Corexit-CEWAF were 261.96 mg/L total extractable hydrocarbons (TEH) and 2.95 mg/L total polycyclic aromatic hydrocarbons (PAH), whereas the mean LC
50
values for all species tested with Finasol-CEWAF were 23.19 mg/L TEH and 0.49 mg/L total PAH. Larval life stages were generally more sensitive to dispersants and dispersed oil than adult life stages within a species. These results will help to inform management decisions regarding the use of oil-spill dispersants.
Polar and but not lateral flagellin proteins from Aeromonas hydrophila strain AH-1 (serotype O11) were found to be glycosylated. Top-down mass spectrometry studies of purified polar flagellins ...suggested the presence of a 403 Da glycan of mass. Bottom-up mass spectrometry studies showed the polar flagellin peptides to be modified with 403 Da glycans in O-linkage. The MS fragmentation pattern of this putative glycan was similar to that of pseudaminic acid derivative. Mutants lacking the biosynthesis of pseudaminic acid (pseB and pseI homologues) were unable to produce polar flagella but no changes were observed in lateral flagella by post-transcriptional regulation of the flagellin. Complementation was achieved by reintroduction of the wild-type pseB and pseI. We compared two pathogenic features (adhesion to eukaryotic cells and biofilm production) between the wild-type strain and two kinds of mutants: mutants lacking polar flagella glycosylation and lacking the O11-antigen lipopolysaccharide (LPS) but with unaltered polar flagella glycosylation. Results suggest that polar flagella glycosylation is extremely important for A. hydrophila AH-1 adhesion to Hep-2 cells and biofilm formation. In addition, we show the importance of the polar flagella glycosylation for immune stimulation of IL-8 production via toll-"like" receptor 5 (TLR5).
The SLC4 family of HCO3 ? transporters Romero, Michael F.; Fulton, Christiaan M.; Boron, Walter F.
Pflügers Archiv,
2/2004, Letnik:
447, Številka:
5
Journal Article
Recenzirano
The SLC4 family consists of ten genes. All appear to encode integral membrane proteins with very similar hydropathy plots--consistent with the presence of 10-14 transmembrane segments. At least eight ...SLC4 members encode proteins that transport HCO^sub 3^^sup -^ (or a related species, such as CO^sub 3^^sup 2-^) across the plasma membrane. Functionally, these eight proteins fall into two major groups: three Cl-HCO^sub 3^ exchangers (AE1-3) and five Na^sup +^-coupled HCO^sub 3^^sup -^ transporters (NBCe1, NBCe2, NBCn1, NDCBE, NCBE). Two of the Na^sup +^-coupled HCO^sub 3^^sup -^transporters (NBCe1, NBCe2) are electrogenic; the other three Na^sup +^-coupled HCO^sub 3^^sup -^ transporters and all three AEs are electroneutral. At least NDCBE transports Cl^sup -^ in addition to Na^sup +^ and HCO^sub 3^^sup -^. Whether NCBE transports Cl^sup -^--in addition to Na^sup +^ and HCO^sub 3^^sup -^--is unsettled. In addition, two other SLC4 members (AE4 and BTR1) do not yet have a firmly established function; on the basis of homology, they fall between the two major groups. A characteristic of many, though not all, SLC4 members is inhibition by 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS). SLC4 gene products play important roles in the carriage of CO^sub 2^ by erythrocytes, the absorption or secretion of H^sup +^ or HCO^sub 3^^sup -^ by several epithelia, as well as the regulation of cell volume and intracellular pH.PUBLICATION ABSTRACT
Automated driving technology along with electric propulsion are widely expected to fundamentally change our transport systems. They may not only allow a more productive use of travel time, but will ...likely trigger completely new business models in the mobility market. A key determinant of the future prospects of both existing and new mobility services will be their production costs. Hence, in this research the production costs of various transport modes both today and in an automated-electric future are analyzed. To account for different local contexts, the study is conducted for 17 cities across the globe. The results indicate that high-income countries will benefit the most from vehicle automation, while only smaller changes can be expected in lower-income countries. This is due to the different relative contribution of labor cost to the total cost of current taxi and bus operations. In a likely final state, transportation costs will be largely decoupled from a country’s income level, which will favor productivity in higher-income locations. While this research provides valuable first insights into potential future developments, the underlying assumptions will need to be updated as better information becomes available.
A new superconducting magnet test facility was created at the MIT Plasma Science and Fusion Center (PSFC) for the SPARC Toroidal Field Model Coil (TFMC) program. The facility was designed and ...constructed in parallel with the TFMC between 2019 and 2021, with capabilities and design approaches tailored to the needs of this project and its time line. The major components of the facility include a new cryostat (outer dimensions, 5.3 m × 3.7 m × 1.5 m) with open bore; a novel cooling system circulating supercritical helium in a closed loop to provide <inline-formula><tex-math notation="LaTeX">\sim</tex-math></inline-formula>600 W cooling power at <inline-formula><tex-math notation="LaTeX">\sim</tex-math></inline-formula>20 bar-a, <inline-formula><tex-math notation="LaTeX">\sim</tex-math></inline-formula>20 K; a 50-kA <inline-formula><tex-math notation="LaTeX">\pm</tex-math></inline-formula> 10-V power supply with supporting nitrogen-cooled high temperature superconductor (HTS) binary current leads operating at record currents, as well as VIPER-cable HTS cold bus; and a new instrumentation and programmable-logic-controller-based control system handling <inline-formula><tex-math notation="LaTeX">\sim</tex-math></inline-formula>650 input and output signals distributed between the facility and the test article. Substantial legacy infrastructure inherited from the PSFC's Alcator C-Mod tokamak program, including liquid nitrogen facilities and 10 MW of ac power, was instrumental in the rapid deployment of these new systems. Immediately after initial commissioning, the facility was used successfully to test the SPARC TFMC, operating the magnet in a campaign achieving 20 T on the coil, as well as a second campaign performing quench testing. The facility has since undergone several upgrades and has been used in campaigns of other test articles, and it is expected that the facility will remain a resource for the community for the foreseeable future to develop fusion magnets and related technology.
In a large population of animals, it is normal to have some die each day from causes not related to disease, which is often referred to as natural causes. In poultry production, this phenomenon is ...commonly referred to as daily mortality. In egg-producing chickens, many of the natural causes of death are associated with making an egg. The causes of normal mortality in commercial egg-laying chicken flocks have been described very little to date. A commercial chicken egg farm, housing approximately two million single-comb white leghorn chickens (Gallus gallus domesticus) in 16 egg-producing flocks, was visited on a monthly basis to monitor bird health, body conditioning, skeletal integrity, and causes of daily mortality in an attempt to provide early detection of health abnormalities. A representative sample of daily mortality from each flock was necropsied to determine the cause of death. Reported herein is a summary of visits for a period of 38 mo from June 2011 to July 2014. The top 15 causes of normal mortality, in rank order of prevalence, were determined to be the following: egg yolk peritonitis, hypocalcemia, gout, self-induced molt, salpingitis, caught by spur, intussusception or volvulus (twisted intestine), cannibalism (pick out), tracheal plug, septicemia, fatty liver syndrome, internal layer, layer hepatitis, persecution, and prolapsed vent. Other causes noted were hyperthermia (during summer), trauma, coccidiosis, ovarian neoplasia, being egg bound, urolithiasis, peritonitis (not egg yolk induced), leg fracture, caught in the structure, tumor (other than ovarian origin), wing fracture, exsanguination, and cardiomyopathy.
The results from a cross-country empirical analysis show that corporate governance and ethics are linked to national scores of subjective well-being. This impact is over and above the effect that ...corporate governance has on national income, suggesting that people value corporate governance for additional reasons besides its economic impact.
Polar flagellin proteins from Aeromonas hydrophila strain AH-3 (serotype O34) were found to be O-glycosylated with a heterogeneous glycan. Mutants unable to produce WecP or Gne enzymes showed altered ...motility, and the study of their polar flagellin glycosylation showed that the patterns of glycosylation differed from that observed with wild type polar flagellin. This suggested the involvement of a lipid carrier in glycosylation. A gene coding for an enzyme linking sugar to a lipid carrier was identified in strain AH-3 (WecX) and subsequent mutation abolished completely motility, flagella production by EM, and flagellin glycosylation. This is the first report of a lipid carrier involved in flagella O-glycosylation. A molecular model has been proposed. The results obtained suggested that the N-acetylhexosamines are N-acetylgalactosamines and that the heptasaccharide is completely independent of the O34-antigen lipopolysaccharide. Furthermore, by comparing the mutants with differing degrees of polar flagellin glycosylation, we established their importance in A. hydrophila flagella formation and motility.
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