Bacterial survival, lymph node pathology, and serological responses of bison (Bison bison) vaccinated with Brucella abortus strain RB51 or strain 19

From August 1993 to June 1994, 3 month-old bison (Bison bison) were vaccinated with Brucella abortus strain RB51 (SRB51, n = 6), strain 19 (S19, n = 3), or with saline (n = 1) and serologic responses and persistence of vaccine strains within lymph nodes were monitored. Bison vaccinated with S19 had granulomatous lymphadenitis and greater peak numbers of B. abortus than those vaccinated with SRB51. Bison vaccinated with RB51 had similar histological lesions and B. abortus were still present in lymph nodes at 16 weeks. Although antibodies against RB51 were produced, standard tube agglutination test responses of RB51-vaccinates remained negative. The histological lesions of B. abortus infections in bison were similar to those observed in cattle, but bison did not clear SRB51 as rapidly as cattle.     

Effects of Sulphate-reducing Bacteria on Corrosion Behaviour of 2205 Duplex Stainless Steel

The effects of sulphate-reducing bacteria(SRB)on the 2205 duplex stainless steel in the sea water and oil industry environments were studied by electrochemical impedance spectroscopy(EIS),potentiodynamic polarization and microorganism analysis.The results showed that the detected SRB was the non-spore bacillus of about 0.8μm×(1.8-2.2)μm in size and the content of S was about 7.59% in the corrosion products.SRB contributed to the corrosion evolution which caused the corrosion failure of 2205 duplex stainless steel pipe in the liquid hydrocarbon cooler.During the corrosion process,the produced H2S could significantly influence the anodic process and finally accelerate the corrosion.SEM observation indicated that the distribution of SRB on the surface of 2205 duplex stainless steel was nonuniform.X-ray photoelectron spectroscopy analysis revealed that the surface film was composed of Cr2O3,MoO3,FeS,FeS2,Fe(OH)2 and FeO after immersing the sample in the SRB medium for 14d.     

Effect of Sulfate Reduced Bacterium on Corrosion Behavior of 10CrMoAl Steel

 The effects of sulfate reduced bacterium (SRB) on the corrosion behavior of 10CrMoAl steel in seawater were studied by chemical immersion, potentiodynamic polarization, electrochemical impedance spectroscopy measurement, and scanning electron microscope techniques. The results show that the content of element sulfur in the corrosion product of 10CrMoAl steel in seawater with SRB is up to 923%, which is higher than that of the same in sterile seawater. X ray diffraction demonstrates that the main corrosion product is FeS. SRB increases the corrosion rate by anodic depolarization of the metabolized sulfide product. SEM observation indicates that the corrosion product is not distributed continuously; in addition, bacilliform sulfate reduced bacterium accumulates on the local surface of 10CrMoAl steel. Hence, SRB enhances sensitivity to the localized corrosion of 10CrMoAl steel in seawater.     

Microbiologically Induced Corrosion Action on Al-6Mg-Zr and Al-6Mg-Zr-Sc

The corrosion behaviors of Al-6Mg-Zr and Al-6Mg-Zr-Sc in sulfate-reducing bacteria（SRB） solution in the anaerobic environment were studied by electrochemical, microbiology and surface analysis methods. It is found that the oxide film is more compact resulting in the open circuit potential shifting about 100 mV positively due to the addition of Sc. On the other hand, it is demonstrated that pitting sensitivity of Al-6Mg-Zr-Sc alloy in the SRB solution is decreased and its microbiologically influenced corrosion resistance is improved.     

Experimental infection of pregnant cattle with the vaccine candidate Brucella abortus strain RB51: pathologic, bacteriologic, and serologic findings

To determine the placental tropism and abortigenicity of the vaccine candidate Brucella abortus strain RB51 (SRB51), a rough mutant of the virulent strain 2308, ten Polled Hereford heifers were inoculated intravenously in the 6th month of gestation. Heifers were euthanatized and examined at postinoculation week (PIW) 8 (n = 5) or at full term (n = 5). Four of five infected heifers sampled at PIW 8 and three of four infected heifers at term had placentitis, whereas reproductive tissues of three normal cows used for comparison had no placentitis. Numerous macrophages, immunoreactive for SRB51 antigen, as well as neutrophils, fibrin, and cell debris filled the arcade zone between chorion and maternal septae. Trophoblastic epithelium of the placentomal arcade zone had intracellular bacteria that were immunoreactive for SRB51 antigen. The tips of maternal septa had a lymphoplasmacytic infiltrate with small multifocal erosions and ulcerations of maternal epithelium. SRB51 was cultured from all tissues in which lesions were seen. Placentae of one cow from each group had no placentitis and contained no SRB51. In mammae, interstitial lymphoplasmacytic infiltrates and suppurative infiltrates within alveoli and intralobular ductules were seen in two of five heifers at PIW 8. SRB51 was cultured from liver, spleen, lung, and bronchial lymph nodes in four of five calves at PIW 8 and three of four full-term calves, but no lesions were seen. One near-term heifer had disseminated infection, placentitis, and lymphoplasmacytic endometritis, and delivered a premature weak calf. These results establish that SRB51 is less abortifacient than previously published reports with strain 19, in that only one of four heifers delivered prematurely following intravenous inoculation with SRB51, whereas intravenous inoculation with strain 19 leads to 100% abortion. However, it also shows that SRB51 can infect the bovine placenta, mammary gland, and fetus, can induce placentitis, and, in some cases, can lead to preterm expulsion of the fetus.     

温度和硫酸盐还原菌（SRB）协同作用下X80钢的腐蚀行为

摘要：通过利用线性极化曲线,交流阻抗技术（EIS）,并结合使用扫描电子显微镜观察研究了不同温度下SRB对X80管线钢在大港土壤模拟溶液中的腐蚀行为的影响,实验结果表明：SRB会加剧X80管线钢在大港土壤溶液中的腐蚀,当SRB活性受不同温度影响时,其对X80管线钢腐蚀行为产生不同影响。当外界环境温度为30℃时,SRB活性较强,生物膜中细胞密度高,其致密性增加,加速了金属的电化学腐蚀速率。当外界环境温度为50℃时,SRB的活性较低,在金属表面形成的生物膜致密性较差,此时在含SRB模拟溶液与无菌模拟溶液中,X80管线钢所呈现出的电化学腐蚀速率基本一致,且小于30℃时含SRB模拟溶液中的腐蚀速率。     

Study of Microbiologicaily Induced Corrosion Action on Al-6Mg-Zr and Al-6Mg-Zr-Sc

The corrosion behaviors of Al-6Mg-Zr and Al-6Mg-Zr-Sc in the sulfate-reducing bacteria （SRB） solution in anaerobic environment were studied using electrochemical, microbiological, and surface analysis methods. It was found that the oxide film was more compact owing to the addition of Sc resulting in the open circuit potential shifting by about 100mV positively. On the other hand, it was seen that the pitting sensitivity of Al-6Mg-Zr-Sc alloy in SRB solution decreased and its microbiologically influenced corrosion resistance was improved. Pitting corrosion occurring on the surface of the two alloys under the comprehensive action of the metabolism of SRB was observed by SEM. It was obtained by EDS that the corrosion degree increased with time and corrosion was furthered by deposition of the product.     

Investigation of Fluorescent Dyes as Partitioning Tracers for Subsurface Nonaqueous Phase Liquid (NAPL) Characterization

Five fluorescent dyes were evaluated as partitioning tracers for detection and quantification of tetrachloroethylene (PCE): fluorescein, rhodamine WT (RWT), sulforhodamine B (SRB), eosine, and pyranine. Results obtained from batch tests were (a) sorption partitioning coefficients (KP) 0.088±0.025 and 0.091 cm3/g, for RWT and SRB, respectively (eosine and pyranine increased fluorescence after soil/dye batch tests; thus, KP could not be obtained for these tracers) and (b) nonaqueous phase liquid/water partitioning coefficients (KNW) for RWT, SRB, and eosine were 0.1703, 0.0603, and 0.049, respectively (pyranine also increased fluorescence in PCE/dye tests). Retardation factors (Rf) measured in column tests for fluorescein, RWT, SRB, eosine, and pyranine were (a) 1.08±0.07, 1.64±0.38, 1.23, 1.45, and 2.97, in the absence of PCE; and (b) 1.31, 2.3, 1.33, 1.79, and 3.51, in the presence of PCE, respectively. The results of this study suggested that the partitioning behavior of the tracers tested is different from simple hydrophobic partitioning and that their fluorescence is complex and dependent upon several variables. Column tests indicated that RWT, SRB, and eosine are possibly suitable as partitioning tracers.     

X100管线钢在含SRB的近中性土壤溶液中的腐蚀行为

采用电化学技术、表面分析技术和失重法,研究了X100管线钢在有/无SRB的近中性土壤溶液中的腐蚀过程与行为。结果表明,X100管线钢在有/无SRB的近中性土壤溶液中的腐蚀均属于中度腐蚀,SRB的活动与代谢影响了X100钢的腐蚀行为,随着腐蚀时间的增加,SRB可在X100钢表面形成由微生物膜与腐蚀产物结合在一起的更加致密的结合膜,对腐蚀传质有一定的阻碍作用,进而减缓了X100钢的腐蚀;而无菌时X100钢表面的腐蚀产物比较疏松,厚度不均匀,对钢基体的保护作用差,导致X100钢在无菌溶液中的腐蚀速率大于有菌时,说明SRB具有减缓X100管线钢腐蚀的作用。不含SRB时X100钢的腐蚀产物主要为铁的氧化物(α-FeO(OH)和Fe_3O_4),含SRB时腐蚀产物主要为铁的氧化物和铁的硫化物(Fe_3O4和FeS)。     

Corrosion of mild steel in sea mud containing sulphate reducing bacteria

In this work, the corrosion behaviour of a mild steel was studied in a sea mud extracted solution in the absence and presence of sulphate reducing bacteria (SRB) by electrochemical impedance spectroscope measurements and scanning electron microscope characterisation. The presence of SRB in the sea mud extracted solution affects corrosion of steel remarkably. In the absence of SRB, the steel corrosion is somewhat inhibited by the formed corrosion product layer. However, the addition of SRB enhances corrosion of the steel due to its metabolism activity. It is speculated that the formed sulphide product may experience transformation decreasing the protectiveness of the product layer.

Dans ce travail, on a étudié le comportement à la corrosion d’un acier doux dans une solution extraite de la boue marine, avec ou sans la présence de bactéries sulfatoréductrices (SRB), au moyen de mesures au spectroscope de l’impédance électrochimique et de la caractérisation au microscope électronique à balayage. La présence de SRB dans la solution extraite de la boue marine affecte la corrosion de l’acier de façon remarquable. En absence de SRB, la corrosion de l’acier est quelque peu inhibée par la couche formée par le produit de la corrosion. Cependant, l’addition de SRB augmente la corrosion de l’acier à cause de l’activité de son métabolisme. L’hypothèse est que le produit sulfuré formé peut se transformer, diminuant ainsi l’effet protecteur de la couche produite.     

Mechanism of Decolorization of Azo Dyes in Anaerobic Mixed Culture

To determine the role of diverse groups of bacteria in the decolorization of a monoazo dye C. I. Reactive Orange 96 (RO 96), batch experiments with an anaerobic mixed culture were made using the selective inhibitors molybdate and 2-bromoethanesulfonic acid (BES). In the presence of acetate and sulfate, inhibition of sulfate reducing bacteria (SRB) by molybdate (8 mmol∕L) caused a significant decrease in the decolorization rate of RO 96. Increases in the SRB inhibitor concentration (20, 38 mmol∕L) led to slower decolorization of RO 96, confirming the contribution of SRB to the decolorization. Inhibition of methane producing bacteria (MPB) with BES (10, 20 mmol∕L), however, did not significantly influence the decolorization, indicating that MPB took no part in the decolorization. In the presence of lactate and sulfate, SRB also contributed to the decolorization of RO 96. The mechanism of decolorization of azo dyes based on extracellular chemical reduction with sulfide was postulated. Sulfide produced via sulfate respiration by SRB chemically decolorizes azo dyes.     

Phenytoin as a countermeasure for motion sickness in NASA maritime operations

Seasickness is the most prevalent form of motion sickness and is an operational problem during Space Shuttle Solid-fueled Rocket Booster (SRB) retrieval. Phenytoin has been shown to protect against motion sickness induced by Coriolis stress. We exposed SRB recovery personnel to off-vertical rotation and sea motion after phenytoin or placebo. Phenytoin blood levels of at least 9 micrograms/ml were protective against motion sickness at sea. No change in susceptibility to nitrogen narcosis was seen in divers in chamber tests at 460 KPa. Phenytoin was used during performance of critical and hazardous tasks during training and actual SRB recovery operations. Phenytoin is an effective operational countermeasure for motion sickness for selected SRB crewmembers.     

Spatial Variation of Sediment Sulfate Reduction Rates in a Saline Lake

Devils Lake in North Dakota is a terminal, multibasin, saline lake with an overall surface area that is currently approximately 44,520?ha (110,000?acres). Lake elevation has increased by more than 7?m within 10?years, and vast areas of prairie and cropland have been flooded. The lake is rich in sulfate, and water column sulfate concentrations are relatively uniform within each of the five major basins, but increase from 3.1?mM (300?mg/L) in West Bay to 31?mM (3,000?mg/L) in East Devils Lake. Sediment cores were collected from three of the basins at different water depths, and used in laboratory studies to evaluate the spatial distribution of sulfate-reducing bacteria (SRB) activity in the lake sediments. The high sulfate concentrations within the experimental sediment cores suggest that the activity of SRB is limited by the availability of suitable electron donors rather than by the availability of sulfate and that SRB activity can be defined by a zero-order volumetric rate constant (K0). Experimentally determined K0 values ranged from 11?to?88?mmol SO42? m?3?day?1. The water depths from which sediment cores were collected in Devils Lake are related to the elapsed time since inundation by the rising lake level. It was found that time since inundation influences the observed K0 value. Mean K0 values for cores from an average depth of 4.8?m (submergence time of about 5?years), and 9.4?m (submergence time of about 28?years) were 62 and 17?mmol SO42? m?3?day?1, respectively. The significant difference (two-tailed t-test, p<0.05) suggests that SRB activities in the Devils Lake sediments change with submergence times. A uniform sulfate reduction rate applied to all Devils Lake sediments is therefore only a crude approximation of reality.     

Exposure to 60 Hz magnetic fields and risk of lymphoma in PIM transgenic and TSG-p53 (p53 knockout) mice

The results of a number of epidemiology studies suggest that exposure to power frequency (50 and 60 Hz) magnetic fields may be a risk factor for hematopoietic neoplasia. To generate experimental data to test this hypothesis, the influence of magnetic field exposure on lymphoma induction was determined in two strains of mice that are genetically predisposed to the disease. PIM mice, which carry the pim-1 oncogene, are highly sensitive to lymphoma induction by N-ethyl-N-nitrosourea (ENU); ENU-treated PIM mice were studied as a 'high incidence' lymphoma model. TSG-p53 (p53 knockout) mice, in which the p53 tumor suppressor gene has been deleted from the germ line, develop lymphoma as an age-related change; hemizygous TSG-p53 mice were studied as a 'low incidence' lymphoma model. Beginning 1 day after a single i.p. injection of 25 mg ENU/kg body wt, groups of 30 PIM mice/sex were exposed for 18.5 h/day to pure, linearly polarized, transient-free 60 Hz magnetic fields at field strengths of 0 (sham control), 0.02, 2.0 or 10.0 Gauss (G). An additional group of 30 PIM mice/sex was exposed intermittently (1 h on, 1 h off) to 10.0 G fields. Groups of 30 TSG-p53 mice/sex were exposed continuously to magnetic field strengths of 0 (sham control) or 10.0 G; TSG-p53 mice received no ENU. Studies were terminated after 23 weeks of magnetic field exposure. Lymphoma incidence in male PIM mice exposed continuously to 10.0 G magnetic fields was significantly reduced from that seen in sex-matched sham controls; survival, lymphoma incidence and lymphoma latency in other groups of PIM mice did not differ from sham controls. Survival and lymphoma incidence in all groups of TSG-p53 mice was 7% or less, regardless of magnetic field exposure regimen. These data do not support the hypothesis that exposure to magnetic fields is a significant risk factor for lymphoid neoplasia in mice with a genetic predisposition to the disease.     

硫酸盐还原菌在处理酸性矿山废水中的应用

利用硫酸盐还原菌(sulfate reducing bacteria, SRB)处理酸性矿山废水是目前研究的热点，在实际生产活动中有着非常广泛的应用.文章简要介绍酸性矿山废水的来源、特点及其危害，重点介绍SRB处理酸性矿山废水的机理，总结国内外SRB处理工艺在酸性矿山废水中的发展研究，并提出SRB处理酸性矿山废水方面存在的一些问题.      

Effects of high magnetic fields on the flow stress of 18-8 stainless steels

The plastic deformation of two 18-8 stainless steels was studied in magnetic fields as large as 18 T at temperatures of 4, 77 and 290 K. Changes in stress-strain behavior during magnetic exposure at cryogenic temperatures are reported, and are associated with an enhanced f.c.c.→ b.c.c. martensitic transformation. In the magnetic field a reduced flow stress was observed at small strains, but at larger strains an increased rate of work hardening and a larger flow stress were observed. Additionally, a reduced elongation was found for the specimens tested in the magnetic field. Although these effects of magnetic fields are probably too small to be of engineering importance, they provide a unique means of determining how the f.c.c.→ b.c.c. martensitic transformation affects the plastic deformation of 18-8 stainless steels.     

Growth of a human intestinal Desulfovibrio desulfuricans in continuous cultures containing defined populations of saccharolytic and amino acid fermenting bacteria

Ecological and physiological effects of the sulphate-reducing bacterium (SRB) Desulfovibrio desulfuricans on other intestinal organisms were investigated in anaerobic chemostats (dilution rate approximately 0.2 h-1). Reproducible defined bacterial communities were used in these experiments, comprising 14 different saccharolytic and amino acid fermenting species: Bifidobacterium longum, Bif. adolescentis, Bif. pseudolongum, Bif. infantis, Bacteroides thetaiotaomicron, Bact. vulgatus, Lactobacillus acidophilus, Enterococcus faecalis, Ent. faecium, Escherichia coli, Clostridium perfringens, Cl. butyricum, Cl. innocuum, Cl. bifermentans. Lactobacillus and Cl. bifermentans populations never rose above minimum detection limits (log10 2.0 and 4.0, respectively) under the experimental conditions employed in these studies. Inclusion of Des. desulfuricans in bacterial cultures (c. log10 8.4 viable cells ml-1) resulted in marked reductions (i.e. greater than 1 log) in planktonic cell population densities of several species, particularly Bif. longum, Cl. perfringens and Bif. pseudolongum. The two bacteroides species were unaffected by Des. desulfuricans, while numbers of Cl. butyricum increased. Extensive wall growth developed in the SRB culture, consisting mainly of Des. desulfuricans (log10 9.2 viable cells ml-1), Bact. thetaiotaomicron and Bact. vulgatus, with lesser numbers of facultative anaerobes, Cl. perfringens and Bif. longum. Wall growth was associated with a reduction in planktonic cell mass and increased acid production by the cultures. Chemotaxonomic study of chemostat microbiotas, on the basis of cellular fatty acid methyl ester (FAME) analyses, showed the existence of characteristic bacteroides (C15) and bifidobacterial (C18) markers, but desulfovibrio markers (i-C15:0, C16:0, i-C17:1) could be identified. The metabolic activities of saccharolytic organisms were altered in the SRB chemostat, including synthesis of a number of hydrolytic enzymes involved in carbohydrate breakdown, such as alpha-galactosidase, alpha-glucosidase and beta-galactosidase, together with several mucinolytic enzymes. High concentrations of sulphide (8.2 mmol 1-1) were detected in the SRB chemostat, suggesting that this metabolite may have been inhibitory to some species. Saccharolytic organisms growing in the SRB fermenter utilized more starch, but less galactose-containing polymers, which correlated with the observed glycosidase activities. Profound differences were also recorded with respect to fermentation product formation in the chemostats, where a major switch to acetate production occurred in the SRB culture, with concomitant reductions in propionate, butyrate and lactate, which is an important electron donor for desulfovibrios.     

Sex ratio at birth deviations in modern Venezuela: the Trivers-Willard effect

This study evaluates the impact of the Trivers-Willard (T-W) effect on human populations, using demographic data collected from vital registration data in Venezuela. The evaluation of the sex ratio at birth (SRB) and of fetal and infant deaths supports the existence of T-W effect in the Venezuelan population in extreme conditions. This T-W effect was observable in the SRB but not at later ages and is related to the marital status of the mother. The results indicate that the investment in females associated with environmental adversity is greater than the investment in males associated with good environmental conditions.     

Increased resorptions in CBA mice exposed to low-frequency magnetic fields: an attempt to replicate earlier observations

This paper has two aims. First, it reports the findings of a study on the effects of low-frequency magnetic fields on reproduction. Second, it serves as an example of an attempt to replicate the results of an experimental study in an independent laboratory and discusses some of the problems of replication studies. To try to replicate the findings of a study reporting increased resorptions (fetal loss) in mice exposed to 20 kHz magnetic fields with sawtooth waveform and to study the possible effects of 50 Hz sinusoidal fields, pregnant mice were exposed to magnetic fields from day 0 to 18 of pregnancy, 24 h per day. The flux densities of the vertical magnetic fields were 15 microT (peak-to-peak) at 20 kHz and 13 or 130 microT (root mean square) at 50 Hz. Two strains of animals were used: CBA/S mice imported from the laboratory reporting the original observations, and a closely related strain CBA/Ca. The CBA/S mice were cleaned of pathogenic microbes and parasites before they were imported into our laboratory. The magnetic field exposures did not affect resorption rate in CBA/Ca mice. In CBA/S, the frequency of resorptions was higher in the exposed mice than in the control group. However, the increase was not significantly different from either the no-effect hypothesis or the results of the original study we were attempting to replicate. Differences between the two studies and difficulties in interpreting the results are discussed. It is concluded that the results tend more to support than argue against increased resorptions in CBA/S mice exposed to the 20 kHz magnetic field. The results demonstrate that animal strain is an important variable in bioelectromagnetics research: even closely related strains may show different responses to magnetic field exposure.