The bacterial diversity associated with bacterial diseases on Mud Crab (Scylla serrata Fab.) from Pemalang Coast, Indonesia

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Sarjito; Desrina; Haditomo, AHC; Budi Prayitno, S.

2018-05-01

Bacterial disease is a problem in mud crab culture in Pemalang, Indonesia. The purpose of this study was to find out the bacteria associated with bacterial diseases on mud crab based on the molecular approach. Exploratory methods were conducted in this reserach. Twenty two bacteria (SJP 01 – SJP 22) were isolated from carapace and gills and hepathopancreas of moribound mud crab with TCBS and TSA medium. Based on rep PCR, five isolates (SJP 01, SJP 02, SJP 04, SJP 10 and SJP 11) were choosen for further investigation. Result from 16S rDNA sequence analysis, SJP 01, SJP 02, SJP 04, SJP 10 and SJP 11 were closely related to Exiguobacterium sp. ZJ2505 (99%), V. harveyi strain NCIMB1280 (98%), V. alginolyticus strain ATCC 17749(98%.), B. marisflavi strain TF-11 (97%) and E. aestuarii strain TF-16 (99%) respectively.

The effect of amino acid lysine and methionine addition on feed toward the growth and retention on mud crab (Scylla serrata)

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Alissianto, Y. R.; Sandriani, Z. A.; Rahardja, B. S.; Agustono; Rozi

2018-04-01

High market demand of mud crab (Scylla serrata) encourages farmers to increase the production of mud crab. However, mud crab can not synthesize essential amino acids, so it is necessary to supply essential amino acids such as lysine and methionine in the diet. This study aims to determine the effect of lysine and methionine on feeds to increase growth and retention of mud crabs (Scylla serrata). In this study the amount of lysine amino acid and methionine added to the trash fish diet were: P0 (0: 0%); P1 (0.75: 0.75%); P2 (1: 1%); P3 (1.25: 1.25%); P4 (1.5: 1.5%) with the ratio of lysine and methionine 1: 1. The parameters observed in this study were Survival Rate (SR), Specific Growth Rate (SGR), Feed Conversion Ratio (FCR), Efficiency Feed (EF), protein retention and energy retention. The results of the 35-day maintenance study showed significant differences (P protein retention and no significant effect (P> 0.05) on energy retention and Survival Rate (SR) on mud crab. The best results in this study were found in P4 treatment with addition of lysine amino acids and methionine (1.5: 1.5%).

The effect of different feed on the spawning performance of mud crab Scylla serrata broodstock

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Bethsy J. Pattiasina

2013-11-01

Full Text Available Mud crab is one of the 12 aquaculture commodities of Ministry of Maritime Affairs and Fisheries. Control of reproduction to increase seed production through feed improvement, is one of the challenges and strategies in the mud crab aquaculture. Due to lack of knowledge about broodstock nutrition lead to producing rate of seeds still relatively low. This study aimed to obtain information on the kind of feed that has specific nutrient and plays a role in increasing the success of spawning and zoea survival. Mud crab of Scylla serrata with initial weight of 500.7±103.4 g, preferably under developed gonads were maintained in a fiber tank measuring length of 2.48 m, width 1.26 m, and a height of 60 cm which is partition sealed into 30×40×60 cm3 to put one crab. Tank was equipped with sand as a substrate as high as 15 cm and seawater system with flow rate of 1 L per six minutes and 25 cm high water. Treatments were consisted of: 1. PI (fresh meat fish of Decapterus sp. with dose of 5%, 2. PSC (fresh meat mixture of Decapterus sp. 1.8%, 3% of squid, and shrimp 1.2%, 3. PB (artificial feed dose of 10% of BW, each treatment was repeated three times. Parameters measured were the duration of ovarian to mature, egg diameter, hatching rate, fecundity, and zoea production. Data were analyzed using ANOVA. The quality of larval measured by survival and larval fat and protein content. The results showed that crabs treated by PI and PSC showed faster to get mature compared to PB treatment (p<0.05. Hatching rate of larvae in PSC treatment was higher compared to PI and PB treatments (p<0.05. Furthermore, all treatments did not affect egg diameter, fecundity, and the number of zoea (p>0.05. In conclusion, crab which fed fresh meat (PI and PSC could get mature earlier, and have high percentage of the larval hatching than those of fed by PB. In fact that larvae from broodstock feed of PI has survival as well as protein and fat content were higher than those of fed

A review of maturation diets for mud crab genus Scylla broodstock: Present research, problems and future perspective.

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Azra, Mohamad N; Ikhwanuddin, Mhd

2016-03-01

Study of broodstock maturation diets is important in order to increase the quality of berried females, which indirectly improve the larval quantity in the hatchery production of cultured species. This paper reviewed the studies on the maturation diets for mud crab broodstock, genus Scylla and compared independently to identify their effect on reproductive performance and larval quality. The broodstock is usually caught from the wild and held in the spawning or maturation tank for further use of hatchery seed production. Mud crab broodstock was fed either natural diet, artificial diet or mixed diet. Trash fishes were commonly used as a natural feed for mud crab broodstock; meanwhile artificial diets are from formulated fish meal and various kinds of feed. The results indicated that mud crab broodstock has a high dietary requirement for lipids, fatty acids and protein which are to be used during the maturation and breeding processes. However, the natural diet produce better larval quality compared to the artificial diet. The mixed diet is the better diet which resulted in better reproductive performances such as growth, survival, fecundity and maturation processes. This review also discusses the problems in the previous studies for the potential future research to develop very high quality and cost-effective formulated diet for the enhancement of broodstock and seed production technology. Information from this review can be useful in developing a better quality of crustacean broodstock's diet for commercial hatchery production.

Macrophage migration inhibitory factor (MIF) family in arthropods: Cloning and expression analysis of two MIF and one D-dopachrome tautomerase (DDT) homologues in mud crabs, Scylla paramamosain.

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Huang, Wen-Shu; Duan, Li-Peng; Huang, Bei; Wang, Ke-Jian; Zhang, Cai-Liang; Jia, Qin-Qin; Nie, Pin; Wang, Tiehui

2016-03-01

The macrophage migration inhibitory factor (MIF) family, consisting of MIF and D-dopachrome tautomerase (DDT) in vertebrates, is evolutionarily ancient and has been found across Kingdoms including vertebrates, invertebrates, plants and bacteria. The mammalian MIF family are chemokines at the top of the inflammatory cascade in combating infections. They also possess enzymatic activities, e.g. DDT catalysis results in the production of 5,6-dihydroxyindole (DHI), a precursor of eumelanin. MIF-like genes are widely distributed, but DDT-like genes have only been described in vertebrates and a nematode. In this report, we cloned a DDT-like gene, for the first time in arthropods, and a second MIF in mud crab. The mud crab MIF family have a three exon/two intron structure as seen in vertebrates. The identification of a DDT-like gene in mud crab and other arthropods suggests that the separation of MIF and DDT preceded the divergence of protostomes and deuterostomes. The MIF family is differentially expressed in tissues of adults and during embryonic development and early life. The high level expression of the MIF family in immune tissues, such as intestine and hepatopancreas, suggests an important role in mud crab innate immunity. Mud crab DDT is highly expressed in early embryos, in megalops and crablets and this coincides with the requirement for melanisation in egg chorion tanning and cuticular hardening in arthropods, suggesting a potential novel role of DDT in melanogenesis via its tautomerase activity to produce DHI in mud crab. The clarification of the presence of both MIF and DDT in this report paves the way for further investigation of their functional roles in immunity and in melanogenesis in mud crab and other arthropods. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification of a serine proteinase homolog (Sp-SPH) involved in immune defense in the mud crab Scylla paramamosain.

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Zhang, Qiu-xia; Liu, Hai-peng; Chen, Rong-yuan; Shen, Kai-li; Wang, Ke-jian

2013-01-01

Clip domain serine proteinase homologs are involved in many biological processes including immune response. To identify the immune function of a serine proteinase homolog (Sp-SPH), originally isolated from hemocytes of the mud crab, Scylla paramamosain, the Sp-SPH was expressed recombinantly and purified for further studies. It was found that the Sp-SPH protein could bind to a number of bacteria (including Aeromonas hydrophila, Escherichia coli, Staphylococcus aureus, Vibrio fluvialis, Vibrio harveyi and Vibrio parahemolyticus), bacterial cell wall components such as lipopolysaccharide or peptidoglycan (PGN), and β-1, 3-glucan of fungus. But no direct antibacterial activity of Sp-SPH protein was shown by using minimum inhibitory concentration or minimum bactericidal concentration assays. Nevertheless, the Sp-SPH protein was found to significantly enhance the crab hemocyte adhesion activity (paired t-test, Pparahemolyticus which were both recognized by Sp-SPH protein, if pre-incubated with Sp-SPH protein, respectively. Whereas, the crabs died much faster when challenged with Vibrio alginolyiicus, a pathogenic bacterium not recognized by Sp-SPH protein, compared to those of crabs challenged with A. hydrophila or V. parahemolyticus when pre-coated with Sp-SPH protein. Taken together, these data suggested that Sp-SPH molecule might play an important role in immune defense against bacterial infection in the mud crab S. paramamosain.

Feasibility study on the culture of mud crab Scylla serrata in the mid coast region of Bangladesh.

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Mahmud, A I; Mamun, Abdullah-Al

2012-12-15

A study was conducted at Hatiya and Nijhum Island, Noakhali in the mid coastal region of Bangladesh to identify feasibility of mud crab culture for a study period of six months from January 2010 to June 2010. Data were collected through questionnaire interviews, focus group discussions and cross check interviews. Average yearly collection of mud crabs in this area was about 890.36 tons where lower grade crabs 45.16% and these can be brought under culture practice. It has observed that saline water intrusion was evident 670 Ha. In Hatiya and vast inundated area with saline water was found in Nijhum Island. Overall waiter salinity range was between 2-10 ppt., pH range of 7.8-8.6 and the soil was silt-loamy. The average temperature of the last three years was approximately 26.10 degrees C and rainfall was almost 10.85 mm. It was observed that natural feeds were available in this study area and there was existed a small potential marketing channel with 3-4 middlemen. Also there was a good transportation system both water and road way. So, present study revealed that the area is suitable for crab culture during April to October.

Identification of a Serine Proteinase Homolog (Sp-SPH) Involved in Immune Defense in the Mud Crab Scylla paramamosain

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Zhang, Qiu-xia; Liu, Hai-peng; Chen, Rong-yuan; Shen, Kai-li; Wang, Ke-jian

2013-01-01

Clip domain serine proteinase homologs are involved in many biological processes including immune response. To identify the immune function of a serine proteinase homolog (Sp-SPH), originally isolated from hemocytes of the mud crab, Scylla paramamosain, the Sp-SPH was expressed recombinantly and purified for further studies. It was found that the Sp-SPH protein could bind to a number of bacteria (including Aeromonas hydrophila, Escherichia coli, Staphylococcus aureus, Vibrio fluvialis, Vibrio harveyi and Vibrio parahemolyticus), bacterial cell wall components such as lipopolysaccharide or peptidoglycan (PGN), and β-1, 3-glucan of fungus. But no direct antibacterial activity of Sp-SPH protein was shown by using minimum inhibitory concentration or minimum bactericidal concentration assays. Nevertheless, the Sp-SPH protein was found to significantly enhance the crab hemocyte adhesion activity (paired t-test, Pparahemolyticus which were both recognized by Sp-SPH protein, if pre-incubated with Sp-SPH protein, respectively. Whereas, the crabs died much faster when challenged with Vibrio alginolyiicus, a pathogenic bacterium not recognized by Sp-SPH protein, compared to those of crabs challenged with A. hydrophila or V. parahemolyticus when pre-coated with Sp-SPH protein. Taken together, these data suggested that Sp-SPH molecule might play an important role in immune defense against bacterial infection in the mud crab S. paramamosain. PMID:23724001

Genetic diversity and connectivity in the East African giant mud crab Scylla serrata: Implications for fisheries management.

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Cyrus Rumisha

Full Text Available The giant mud crab Scylla serrata provides an important source of income and food to coastal communities in East Africa. However, increasing demand and exploitation due to the growing coastal population, export trade, and tourism industry are threatening the sustainability of the wild stock of this species. Because effective management requires a clear understanding of the connectivity among populations, this study was conducted to assess the genetic diversity and connectivity in the East African mangrove crab S. serrata. A section of 535 base pairs of the cytochrome oxidase subunit I (COI gene and eight microsatellite loci were analysed from 230 tissue samples of giant mud crabs collected from Kenya, Tanzania, Mozambique, Madagascar, and South Africa. Microsatellite genetic diversity (He ranged between 0.56 and 0.6. The COI sequences showed 57 different haplotypes associated with low nucleotide diversity (current nucleotide diversity = 0.29%. In addition, the current nucleotide diversity was lower than the historical nucleotide diversity, indicating overexploitation or historical bottlenecks in the recent history of the studied population. Considering that the coastal population is growing rapidly, East African countries should promote sustainable fishing practices and sustainable use of mangrove resources to protect mud crabs and other marine fauna from the increasing pressure of exploitation. While microsatellite loci did not show significant genetic differentiation (p > 0.05, COI sequences revealed significant genetic divergence between sites on the East coast of Madagascar (ECM and sites on the West coast of Madagascar, mainland East Africa, as well as the Seychelles. Since East African countries agreed to achieve the Convention on Biological Diversity (CBD target to protect over 10% of their marine areas by 2020, the observed pattern of connectivity and the measured genetic diversity can serve to provide useful information for designing

Infestation of parasitic rhizocephalan barnacles Sacculina beauforti (Cirripedia, Rhizocephala in edible mud crab, Scylla olivacea

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Khor Waiho

2017-06-01

Full Text Available Screening of mud crab genus Scylla was conducted in four locations (Marudu Bay, Lundu, Taiping, Setiu representing Malaysia. Scylla olivacea with abnormal primary and secondary sexual characters were prevalent (approximately 42.27% of the local screened S. olivacea population in Marudu Bay, Sabah. A total of six different types of abnormalities were described. Crabs with type 1 and type 3 were immature males, type 2 and type 4 were mature males, type 5 were immature females and type 6 were mature females. The abdomen of all crabs with abnormalities were dented on both sides along the abdomen’s middle line. Abnormal crabs showed significant variation in their size, weight, abdomen width and/or gonopod or pleopod length compared to normal individuals. The mean body weight of abnormal crabs (type 1–5 were higher than normal crabs with smaller body size, while females with type 6 abnormality were always heavier than the normal counterparts at any given size. Sacculinid’s externa were observed in the abdomen of crabs with type 4 and type 6 abnormalities. The presence of embryos within the externa and subsequent molecular analysis of partial mitochondrial COI region confirmed the rhizocephalan parasite as Sacculina beauforti. Future in-depth descriptions of the life cycle and characteristics of S. beauforti are recommended as it involves a commercially important edible crab species and the effect on human health from the consumption of crabs is of crucial concern.

Identification of a serine proteinase homolog (Sp-SPH involved in immune defense in the mud crab Scylla paramamosain.

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Qiu-xia Zhang

Full Text Available Clip domain serine proteinase homologs are involved in many biological processes including immune response. To identify the immune function of a serine proteinase homolog (Sp-SPH, originally isolated from hemocytes of the mud crab, Scylla paramamosain, the Sp-SPH was expressed recombinantly and purified for further studies. It was found that the Sp-SPH protein could bind to a number of bacteria (including Aeromonas hydrophila, Escherichia coli, Staphylococcus aureus, Vibrio fluvialis, Vibrio harveyi and Vibrio parahemolyticus, bacterial cell wall components such as lipopolysaccharide or peptidoglycan (PGN, and β-1, 3-glucan of fungus. But no direct antibacterial activity of Sp-SPH protein was shown by using minimum inhibitory concentration or minimum bactericidal concentration assays. Nevertheless, the Sp-SPH protein was found to significantly enhance the crab hemocyte adhesion activity (paired t-test, P<0.05, and increase phenoloxidase activity if triggered by PGN in vitro (paired t-test, P<0.05. Importantly, the Sp-SPH protein was demonstrated to promote the survival rate of the animals after challenge with A. hydrophila or V. parahemolyticus which were both recognized by Sp-SPH protein, if pre-incubated with Sp-SPH protein, respectively. Whereas, the crabs died much faster when challenged with Vibrio alginolyiicus, a pathogenic bacterium not recognized by Sp-SPH protein, compared to those of crabs challenged with A. hydrophila or V. parahemolyticus when pre-coated with Sp-SPH protein. Taken together, these data suggested that Sp-SPH molecule might play an important role in immune defense against bacterial infection in the mud crab S. paramamosain.

C-type lectin B (SpCTL-B) regulates the expression of antimicrobial peptides and promotes phagocytosis in mud crab Scylla paramamosain.

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Wei, Xiaoyuan; Wang, Limin; Sun, Wanwei; Zhang, Ming; Ma, Hongyu; Zhang, Yueling; Zhang, Xinxu; Li, Shengkang

2018-07-01

As pattern recognition receptors, C-type lectins (CTLs) play important roles in immune system of crustaceans through identifying and binding to the conservative pathogen-associated molecular patterns (PAMPs) on pathogen surfaces. In this study, a new CTL, SpCTL-B, was identified from the hemocytes of mud crab Scylla paramamosain. The full-length of SpCTL-B cDNA was 1278 bp with an open reading frame (ORF) of 348 bp. The predicted SpCTL-B protein contains a single carbohydrate-recognition domain (CRD). SpCTL-B transcripts were distributed in all examined tissues with the highest levels in hepatopancreas. After challenged with Vibrio parahaemolyticus, LPS, polyI:C and white spot syndrome virus (WSSV), the mRNA levels of SpCTL-B in hemocytes and hepatopancreas were up-regulated. The recombinant SpCTL-B (rSpCTL-B) purified by Ni-affinity chromatography showed stronger binding activities with Staphylococcus aureus, β-hemolytic Streptococcus, Escherichia coli, Aeromonas hydrophila, Vibrio alginolyticus than those with V. parahaemolyticus and Saccharomyces cerevisiae. rSpCTL-B exhibited a broad spectrum of microorganism-agglutination activities against Gram-positive bacteria (S. aureus, β-hemolytic Streptococcus) and Gram-negative bacteria (E. coli, V. parahaemolyticus, A. hydrophila, V. alginolyticus) in a Ca 2+ -dependent manner. The agglutination activities of rSpCTL-B could be inhibited by D-mannose and LPS, but not by d-fructose and galactose. The antimicrobial assay showed that rSpCTL-B exhibited the growth inhibition against all examined gram-positive bacteria and gram-negative bacteria. When SpCTL-B was silenced by RNAi, the bacterial clearance ability in mud crab was decreased and the transcript levels of five antimicrobial peptides (AMPs) (SpCrustin, SpHistin, SpALF4 (anti-lipopolysaccharide factor), SpALF5 and SpALF6) were significantly decreased in hemocytes. In our study, knockdown of SpCTL-B could down-regulate the expression of SpSTAT at m

PARASITIC AND SYMBIOTIC FAUNA IN OYSTERS (CRASSOSTREA VIRGINICA) AND MUD CRABS (PANOPEUS SPP.) FROM THE CALOOSAHATCHEE ESTUARY, FLORIDA, USA.

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Volety, Aswani K., S. Greg Tolley and James T. Winstead. 2002. Parasitic and Symbiotic Fauna in Oysters (Crassostrea virginica) and Mud Crabs (Panopeus spp.) from the Caloosahatchee Estuary, Florida, USA (Abstract). Presented at the 4th International Conference on Molluscan Shell...

Mud crab susceptibility to disease from white spot syndrome virus is species-dependent

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Sritunyalucksana Kallaya

2010-11-01

Full Text Available Abstract Background Based on a report for one species (Scylla serrata, it is widely believed that mud crabs are relatively resistant to disease caused by white spot syndrome virus (WSSV. We tested this hypothesis by determining the degree of susceptibility in two species of mud crabs, Scylla olivacea and Scylla paramamosain, both of which were identified by mitochondrial 16 S ribosomal gene analysis. We compared single-dose and serial-dose WSSV challenges on S. olivacea and S. paramamosain. Findings In a preliminary test using S. olivacea alone, a dose of 1 × 106 WSSV copies/g gave 100% mortality within 7 days. In a subsequent test, 17 S. olivacea and 13 S. paramamosain were divided into test and control groups for challenge with WSSV at 5 incremental, biweekly doses starting from 1 × 104 and ending at 5 × 106 copies/g. For 11 S. olivacea challenged, 3 specimens died at doses between 1 × 105 and 5 × 105 copies/g and none died for 2 weeks after the subsequent dose (1 × 106 copies/g that was lethal within 7 days in the preliminary test. However, after the final challenge on day 56 (5 × 106 copies/g, the remaining 7 of 11 S. olivacea (63.64% died within 2 weeks. There was no mortality in the buffer-injected control crabs. For 9 S. paramamosain challenged in the same way, 5 (55.56% died after challenge doses between 1 × 104 and 5 × 105 copies/g, and none died for 2 weeks after the challenge dose of 1 × 106 copies/g. After the final challenge (5 × 106 copies/g on day 56, no S. paramamosain died during 2 weeks after the challenge, and 2 of 9 WSSV-infected S. paramamosain (22.22% remained alive together with the control crabs until the end of the test on day 106. Viral loads in these survivors were low when compared to those in the moribund crabs. Conclusions S. olivacea and S. paramamosain show wide variation in response to challenge with WSSV. S. olivacea and S. paramamosain are susceptible to white spot disease, and S. olivacea is more

Serotonin induces ecdysteroidogenesis and methyl farnesoate synthesis in the mud crab, Scylla serrata.

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Girish, B P; Swetha, C H; Reddy, P Sreenivasula

2017-09-02

In the current study, we have examined the role of serotonin in regulating the levels of methyl farnesoate and ecdysteroids in the giant mud crab Scylla serrata and validated that serotonin indeed is a reproductive hormone. Administration of serotonin elevated circulatory levels of methyl farnesoate and ecdysteroids in crabs. Since methyl farnesoate and ecdysteroid act through retinoid X receptor (RXR) and ecdysteroid receptor (EcR) respectively and these receptors are involved in the regulation of reproduction in crustaceans, we have determined the mRNA levels of RXR and EcR in hepatopancreas and ovary after serotonin administration. The expression levels of both RXR and EcR increased significantly in the hepatopancreas and ovary of serotonin injected crabs when compared to the controls. In vitro organ culture studies revealed that incubation of Y-orgas and mandibular organ explants in the presence of serotonin resulted in a significant increase in the secretion of ecdysteroids by Y-organs, but without alterations in MF synthesis in mandibular organs. From the above studies it is evident that serotonin stimulates Y organs resulting in increased ecdysteroidogenesis. Though the circulatory levels methyl farnesoate elevated after serotonin administration, organ culture studies revealed serotonin mediated methyl farnesaote synthesis is indirect probably by inhibiting release of mandibular organ inhibiting hormone from eyestalks. Copyright © 2017 Elsevier Inc. All rights reserved.

Antioxidative-related genes expression following perfluorooctane sulfonate (PFOS) exposure in the intertidal mud crab, Macrophthalmus japonicus

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Park, Kiyun; Nikapitiya, Chamilani; Kwak, Tae-Soo; Kwak, Ihn-Sil

2015-09-01

Perfluorooctane sulfonate (PFOS) is a persistent environmental contaminant that is used as a surfactant in various industries and consumer products. The intertidal mud crab, Macrophthalmus japonicus, is one of the most abundant macrobenthic creatures. In this study, we have investigated the effect of PFOS on the molecular transcription of antioxidant and detoxification signaling in M. japonicus crab. The selected stress response genes were superoxide dismutases (CuZnSOD and MnSOD), catalase (CAT), glutathione peroxidase (GPx), phospholipid hydroperoxide glutathione peroxidase (PHGPx), peroxiredoxin (Prx), and thioredoxin reductase (TrxR). Significant up-regulation of SODs and CAT was observed after 24 and 96 h exposure to PFOS at different concentrations. The gene expression levels of GPx, PHGPx, and TrXR were significantly up-regulated after exposure to PFOS for 96 h. The transcript levels of CAT and PHGPx were induced in dose- and time-dependent manners after PFOS treatments. However, Prx gene expression was significantly up-regulated in M. japonicus crabs exposed to 10 and 30 μg L-1 PFOS for 96 h. Additionally, PFOS toxicity in M. japonicus induced reduced survival rates at relatively high concentrations of PFOS exposure. Our findings support the contention that exposures to PFOS induced the response of genes related to oxidative stress and detoxification in M. japonicus crabs.

Brachyuran crab diversity of lower estuarine mud flats of Mahi River with new record of two species from Gujarat, India

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P. J. Pandya

2013-12-01

Full Text Available A systematic study of brachyuran crab diversity and distribution was carried out for two years on the lower estuarine mud flats of the Mahi River, the upper Gulf of Khambhat, Gujarat. A total of 10 brachyuran crab species belonging to eight genera and eight families were identified. Study documented the distribution and habitat preference of the reported species on the intertidal area. The study records the occurance of two species Dotilla intermedia and Macrophthalmus brevis, for the first time from Gujarat. Moreover the study briefed on the habitat preference, general ethology and morphometry of new recorded species.

Characterization of a novel anti-lipopolysaccharide factor isoform (SpALF5) in mud crab, Scylla paramamosain.

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Sun, Wanwei; Wan, Weisong; Zhu, Shuo; Wang, Shasha; Wang, Shuqi; Wen, Xiaobo; Zheng, Huaiping; Zhang, Yueling; Li, Shengkang

2015-04-01

Anti-lipopolysaccharide factors (ALFs), the potential antimicrobial peptides that bind and neutralize lipopolysaccharide (LPS), are common effectors of innate immunity in crustaceans. In this study, a novel isoform of ALFs (SpALF5) was isolated from the hemocytes of mud crab Scylla paramamosain. The full-length 975bp SpALF5 contains a 375bp open reading frame (ORF) encoding 125 amino acids. Although SpALF5 exhibits a low degree of nucleotide homology with other reported ALFs, it contains the conserved amino acid sequence with a signal peptide and a LPS-binding domain including two conservative cysteine residues. The genomic organization of SpALF5 consists of four exons and three introns, with each intron containing one or more tandem repeats. Unlike most of ALFs mainly distributed in crab hemocytes, SpALF5 transcript was predominantly observed in the brain, muscle and skin, while barely detected in the hemocytes in our study. In situ hybridization assay also showed that SpALF5 mRNA was localized in brain, muscle and skin tissues of mud crab. Further, SpALF5 transcript was significantly up-regulated after challenge with LPS, polyinosinic polycytidylic acid (PolyI:C) (with the except of that in brain), Vibrio parahemolyticus or white spot syndrome virus (WSSV). The recombinant SpALF5 protein showed a varying degree of binding activity towards bacteria and fungus. Moreover, in vitro, the recombinant SpALF5 revealed a strong antimicrobial activity against Gram-negative bacteria (V. parahemolyticus, Vibrio alginolyticus, Escherichia coli, Aeromonas hydrophila) and fungus (Sacchromyces cerevisiae), but could only inhibited the growth of some Gram-positive bacteria like Staphylococcus aureus. The results suggest that SpALF5 is a potent immune protector and plays an important role in immune defense against invading pathogens in S. paramamosain. Copyright © 2014 Elsevier Ltd. All rights reserved.

Optimization of stocking density in intensification of mud crab Scylla serrata cultivation in the resirculation system

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Yuni Puji Hastuti

2017-07-01

Full Text Available ABSTRACT This study aimed to determine optimum stocking density of mud crab Scylla serrata through the applied of different stocking density in every treatment in recirculation system. Experimental design used was complete randomized design (CRD with three density treatments which were 5 (P1, 10 (P2, and 15 ind/container (P3. All treatments replicated three times. The crab with the average of body weight 150 g/ind cultured in a plastic box (40×30×30 cm. Crab was cultured within 60 days and were fed two times a day by at satiation method. The result showed that P2 treatment gave the best result of mangrove crabs production performance among all treatments with 73.33±5.77% survival rate, 0.68±0.01 g/ind/day absolute growth rate and food conversion ratio 10.11±0.01. Treatment P1 gave the good response of stress, it indicated by the lowest glucose of all tretamnets at the level of 31.91 mg/dL in the end of treatment periods. The water quality during study period was fluctuative as affected by different stocking density in the treatments. Keywords: mud crab, stocking density, production performance  ABSTRAK Penelitian ini bertujuan untuk menentukan padat tebar optimal kepiting bakau Scylla serrata melalui penerapan kepadatan tebar yang berbeda pada setiap perlakuan dalam sistem resirkulasi. Rancangan penelitian yang digunakan adalah rancangan acak lengkap dengan tiga perlakuan yaitu 5 (P1, 10 (P2, dan 15 ekor/wadah pemeliharaan (P3 dengan tiga ulangan. Kepiting bakau yang digunakan memiliki berat rata-rata 150 g/ekor. Wadah pemeliharaan yang digunakan selama pemeliharaan adalah kontainer plastik yang berukuran 40×30×30 cm. Pemeliharaan kepiting bakau dilaksanakan selama 60 hari dan diberikan pakan berupa ikan rucah dua kali sehari secara at satiation. Penelitian menunjukkan bahwa perlakuan P2 memberikan hasil kinerja produksi terbaik dibandingkan perlakuan lainnya dengan nilai kelangsungan hidup 73,33±5,77%, laju pertumbuhan mutlak 0,68�

POPULATION BIOLOGY OF MUD CRAB Scylla serrata - Forsskal, 1775 IN MANGROVE ECOSYSTEM OF SUBANG DISTRICT, WEST JAVA

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Ayu Annisa Kumalah

2017-11-01

Full Text Available The study of population biology of mud crab Scylla serrata is necessary to analyse the population dynamics, such as growth of crabs, size distribution, mortality and exploitation rates of S. serrata. Population biology data collection was carried out from March to June 2016 at estuary and silvofishery areas of three stations (Mayangan, Tanjung Tiga and Blanakan villages. Data  were analyzed using analytical methods of FISAT-II (FAO-ICLARM Stock Assessment Toool IIinstruments. The results showed the growth of S. serrata male in Subang distric was positive allometric and the female was negative allometric. Growth coefficient (K ranged from 0.21 to 0.43 in the estuary and from 0.28 to 0.89 in silvofishery area. Exploitation rate in the silvofishery area has been above the maximum exploitation rate. The size distribution of S. serrata in Subang district has the highest frequency at class interval of 106-110 mm (male and of 101-105 mm. The highest abundance of mature female crabs is in May.Keywords : population biology, Scylla serrata, Subang District

Gonad development and size at maturity of the male mud crab Scylla paramamosain (Forsskål, 1755 in a tropical mangrove swamp

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Md. Sherazul Islam

2013-12-01

Full Text Available The reproductive traits and size at sexual maturity of the male mud crab Scylla paramamosain were investigated in Pak Phanang mangrove swamps, Thailand. Samples were taken seven times from the local middlemen mud crab traders during June 2006 to January 2008. Gonad development was determined based on histological appearance that was classified into three stages: 1 Immature (Spermatogonia, 2 Maturing (Spermatocytes and 3 Mature (Spermatids and Spermatozoa. Among the sample population, the highest 72% was under gonad development stage I, whereas mature stage III was only 12%. The size at first maturity was estimated by the external allometric growth and histological observation of gonad. The size at which 50% of individuals attain sexual maturity was estimated by the two mathematical models such as probit analysis and logistic curve. The mean size at first sexual maturity and 50% maturation of male S. paramamosain were 96 mm and 109 mm internal carapace width (ICW which revealed that 88% individuals were immature. The present result suggested that the minimum legal size of male S. paramamosain capture should be >110 mm ICW.

Effects of mesh size and escape gaps on discarding in an Australian giant mud crab (Scylla serrata trap fishery.

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Matt K Broadhurst

Full Text Available In response to concerns over excessive discarding from Australian recreational round traps (with four funnel entrances used to target giant mud crabs, Scylla serrata, an experiment was done to assess the independent and cumulative utility of paired, bottom-located horizontal escape gaps (46×120 mm and increasing mesh size (from 51 to 101 mm. Compared to conventional traps comprising 51-mm mesh throughout, those with the same mesh size and escape gaps caught significantly fewer (by 95% undersize (<85 mm carapace length--CL crabs while maintaining legal catches. Traps made from 101-mm mesh (but with the same funnel entrances as conventional designs and with and without escape gaps similarly retained fewer undersize crabs and also yellowfin bream Acanthopagrus australis (the key bycatch species by up to 94%, but there were concomitant reductions in fishing power for legal sizes of S. serrata. Although there were no immediate mortalities among any discarded crabs, there was a greater bias towards wounding among post molts than late inter-molts and less damage to individuals in the 101-mm conventional than 51-mm conventional traps (without escape gaps. The results support retrospectively fitting escape gaps in conventional S. serrata traps as a means for reducing discarding, but additional work is required to determine appropriate mesh sizes/configurations that maximize species and size selectivity.

Investigation on the interaction between an antimicrobial in aquaculture, malachite green and hemocyanin from mud crab Scylla paramamosain.

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Li, Zhenxing; Tang, Boping; Zhang, Hongmei

2015-01-25

Interaction between malachite green and hemocyanin of crab plays a crucial role in the metabolism, distribution, and efficacy of toxic dyes in aquaculture. The mechanism of interaction between malachite green and Hc from mud crab was studied by using multi-spectral methods and molecular modeling in this work. The spectroscopic and thermodynamic data show that the interaction is a spontaneous process with the estimated enthalpy and entropy changes of -14.85(±1.86) kJ mol(-1) and 30.38(±5.21) J mol(-1) K(-1), respectively. The binding sites of malachite green in hemocyanin mainly locate in the interface of protein. The hydrophobic and electrostatic forces are the primary contributors to the interaction between hemocyanin and malachite green. The results of ultraviolet-vis absorbance, circular dichroism, and synchronous fluorescence spectroscopy suggest that the binding of malachite green to hemocyanin induces some conformational changes of protein. Copyright © 2014 Elsevier B.V. All rights reserved.

Green-synthesized CdS nano-pesticides: Toxicity on young instars of malaria vectors and impact on enzymatic activities of the non-target mud crab Scylla serrata.

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Sujitha, Vasu; Murugan, Kadarkarai; Dinesh, Devakumar; Pandiyan, Amuthvalli; Aruliah, Rajasekar; Hwang, Jiang-Shiou; Kalimuthu, Kandasamy; Panneerselvam, Chellasamy; Higuchi, Akon; Aziz, Al Thabiani; Kumar, Suresh; Alarfaj, Abdullah A; Vaseeharan, Baskaralingam; Canale, Angelo; Benelli, Giovanni

2017-07-01

Currently, nano-formulated mosquito larvicides have been widely proposed to control young instars of malaria vector populations. However, the fate of nanoparticles in the aquatic environment is scarcely known, with special reference to the impact of nanoparticles on enzymatic activity of non-target aquatic invertebrates. In this study, we synthesized CdS nanoparticles using a green protocol relying on the cheap extract of Valoniopsis pachynema algae. CdS nanoparticles showed high toxicity on young instars of the malaria vectors Anopheles stephensi and A. sundaicus. The antimalarial activity of the nano-synthesized product against chloroquine-resistant (CQ-r) Plasmodium falciparum parasites was investigated. From a non-target perspective, we focused on the impact of this novel nano-pesticide on antioxidant enzymes acetylcholinesterase (AChE) and glutathione S-transferase (GST) activities of the mud crab Scylla serrata. The characterization of nanomaterials was carried out by UV-vis and FTIR spectroscopy, as well as SEM and XRD analyses. In mosquitocidal assays, LC 50 of V. pachynema-synthesized CdS nanoparticles on A. stephensi ranged from 16.856 (larva I), to 30.301μg/ml (pupa), while for An. sundaicus they ranged from 13.584 to 22.496μg/ml. The antiplasmodial activity of V. pachynema extract and CdS nanoparticles was evaluated against CQ-r and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. IC 50 of V. pachynema extract was 58.1μg/ml (CQ-s) and 71.46μg/ml (CQ-r), while nano-CdS IC 50 was 76.14μg/ml (CQ-s) and 89.21μg/ml (CQ-r). In enzymatic assays, S. serrata crabs were exposed to sub-lethal concentrations, i.e. 4, 6 and 8μg/ml of CdS nanoparticles, assessing changes in GST and AChE activity after 16days. We observed significantly higher activity of GST, if compared to the control, during the whole experiment period. In addition, a single treatment with CdS nanoparticles led to a significant decrease in AChE activity over time. The toxicity of Cd

The influence of the La Niña-El Niño cycle on giant mud crab (Scylla serrata) catches in Northern Australia

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Meynecke, Jan-Olaf; Grubert, Mark; Arthur, James Michael; Boston, Ray; Lee, Shing Yip

2012-03-01

Mud crabs (Scylla spp.) are a high value commodity harvested in the Indo-West Pacific. Scylla species support important artisanal fisheries in south-east Asia and intensive commercial fisheries in Australia where the market demand and catch has increased markedly over the last decade. Over-fishing of Scylla spp. has been observed at varying levels throughout its distribution. Fluctuations in catch rates and abundance are thought to be driven by climate parameters. Here we analyse monthly, seasonal and annual patterns in catch and effort data (from 1990 to 2008) for the commercial giant mud crab (Scylla serrata) fishery in the Northern Territory, Australia, with corresponding climatic data (rainfall, freshwater runoff, sea surface temperature) and the Southern Oscillation Index (SOI) as an indicator of La Niña/El Niño events. Between 30 and 40% of the variation in catch per unit effort can be explained by rainfall and SOI alone. This result was supported by linear mixed models which identified SOI as the main contributor to the model. Spectral analyses showed that catch peaks coincided with a four year La Niña cycle. One- and two-year time lags (consistent with S. Serrata's life cycle) were also significantly correlated to SOI values and rainfall. These outcomes may assist fishery managers in planning fishing exposure period and duration. Furthermore, findings of this study provide information on the vulnerability of S. serrata to fluctuations in environmental conditions and can help to apply protective measures when and where necessary.

Record of the Buff-fronted Owl (Aegolius harrisii in the Pampa Biome, southern Brazil

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Marluci Müller Rebelato

2011-02-01

Full Text Available We present the second record of the Buff-fronted Owl (Aegolius harrisii in the Pampa Biome, South Brazil. On 17 January 2010 an adult male was found dead at the roadside along the BR-290, São Gabriel municipality, center-east of Rio Grande do Sul state. The specimen probably collided with a car when using the area for foraging. The record reported here agrees with the suggestion that A. harrisii can use disturbed and open areas.

Effect of cadmium exposure on hepatopancreas and gills of the estuary mud crab (Scylla paramamosain): Histopathological changes and expression characterization of stress response genes.

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Zhu, Qi-Hui; Zhou, Zhong-Kai; Tu, Dan-Dan; Zhou, Yi-Lian; Wang, Cong; Liu, Ze-Peng; Gu, Wen-Bin; Chen, Yu-Yin; Shu, Miao-An

2018-02-01

Cadmium (Cd) is a heavy metal that accumulates easily in organisms and causes several detrimental effects, including tissue damage. Cd contamination from anthropogenic terrestrial sources flows into rivers, and through estuaries to the ocean. To evaluate the toxic effects of Cd on estuary crustaceans, we exposed the mud crab Scylla paramamosain to various Cd concentrations (0, 10.0, 20.0, and 40.0mg/L) for 24h. We also exposed mud crabs to a fixed Cd concentration (20.0mg/L) for various periods of time (0, 6, 12, 24, 48, and 72h). We observed that after exposure to Cd, the surfaces of the gill lamellae were wrinkled, and the morphologies of the nuclei and mitochondria in the hepatopancreas were altered. We analyzed the expression profiles of 36 stress-related genes after Cd exposure, including those encoding metallothioneins, heat shock proteins, apoptosis-related proteins, and antioxidant proteins, with quantitative reverse transcription PCR. We found that exposure to Cd altered gene expression, and that some genes might be suitable bioindicators of Cd stress. Gene expression profiles were organ-, duration-, and concentration-dependent, suggesting that stress-response genes might be involved in an innate defense system for handling heavy metal exposure. To the best of our knowledge, this study is the first one of histopathology and stress-response gene expression pattern of Scylla paramamosain after Cd exposure. Our work could increase our understanding of the effect of environmental toxins on estuary crustaceans. Copyright © 2017 Elsevier B.V. All rights reserved.

Ocean acidification impairs crab foraging behaviour.

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Dodd, Luke F; Grabowski, Jonathan H; Piehler, Michael F; Westfield, Isaac; Ries, Justin B

2015-07-07

Anthropogenic elevation of atmospheric CO2 is driving global-scale ocean acidification, which consequently influences calcification rates of many marine invertebrates and potentially alters their susceptibility to predation. Ocean acidification may also impair an organism's ability to process environmental and biological cues. These counteracting impacts make it challenging to predict how acidification will alter species interactions and community structure. To examine effects of acidification on consumptive and behavioural interactions between mud crabs (Panopeus herbstii) and oysters (Crassostrea virginica), oysters were reared with and without caged crabs for 71 days at three pCO2 levels. During subsequent predation trials, acidification reduced prey consumption, handling time and duration of unsuccessful predation attempt. These negative effects of ocean acidification on crab foraging behaviour more than offset any benefit to crabs resulting from a reduction in the net rate of oyster calcification. These findings reveal that efforts to evaluate how acidification will alter marine food webs should include quantifying impacts on both calcification rates and animal behaviour. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Identification of genes associated with reproduction in the Mud Crab (Scylla olivacea) and their differential expression following serotonin stimulation.

Science.gov (United States)

Kornthong, Napamanee; Cummins, Scott F; Chotwiwatthanakun, Charoonroj; Khornchatri, Kanjana; Engsusophon, Attakorn; Hanna, Peter J; Sobhon, Prasert

2014-01-01

The central nervous system (CNS) is often intimately involved in reproduction control and is therefore a target organ for transcriptomic investigations to identify reproduction-associated genes. In this study, 454 transcriptome sequencing was performed on pooled brain and ventral nerve cord of the female mud crab (Scylla olivacea) following serotonin injection (5 µg/g BW). A total of 197,468 sequence reads was obtained with an average length of 828 bp. Approximately 38.7% of 2,183 isotigs matched with significant similarity (E value reproductive-related genes, namely farnesoic acid o-methyltransferase (FAMeT), estrogen sulfotransferase (ESULT) and prostaglandin F synthase (PGFS). Following serotonin injection, which would normally initiate reproductive processes, we found up-regulation of FAMeT, ESULT and PGFS expression in the female CNS and ovary. Our data here provides an invaluable new resource for understanding the molecular role of the CNS on reproduction in S. olivacea.

Isolation of Lactic Acid Bacteria That Produce Protease and Bacteriocin-Like Substance From Mud Crab (Scylla sp. Digestive Tract (Isolasi Bakteri Asam Laktat yang Menghasilkan Protease dan Senyawa Bacteriocin-Like dari Saluran Pencernaan Kepiting

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Heru Pramono

2015-03-01

Kata kunci: Bakteri Asam Laktat, Bakteriosin-like substance, Protease, Scylla  sp. Digestive tract is complex environment consist of large amount of bacteria’s species. Fish intestine bacteria consist of aerobic or facultative anaerob bacteria which can produce antibacterial and enzym. The objectives of this research were to isolated lactic acid bacteria that produce bacteriocin-like and protease from mud crab digestive tract. Isolation and characterization of isolates were conducted employing media MRS.  Neutralized cell free supernatant of isolates were tested using disc diffusion agar of against pathogenic and spoilage bacteria to indicate bacteriocin-like-producing lactic acid bacteria. Protease-producing isolate was tested using disc diffusion method in casein agar. Among a hundred isolates, 96 isolates were showed clear zone in MRS+CaCO3,, catalase negative, and Gram positive bacteria. Thirty four isolates produced protease and only four isolates (i.e. IKP29, IKP30, IKP52, and IKP94 showed strong inhibition against pathogenic and spoilage bacteria. There were three patterns of inhibition among three isolates against Bacillus subtilis, Staphylococcus aureus, Eschericia coli, and Salmonella sp. All three isolates showed potential uses for produce starter culture for fishery product fermentation purpose. This is the first report of isolation lactic acid bacteria that produced protease and bacteriocin-like from digestive tract of mud crab. Keywords: Lactic acid bacteria, Bacteriocin-like substance, Protease, Scylla  sp.

The variable colours of the fiddler crab Uca vomeris and their relation to background and predation.

Science.gov (United States)

Hemmi, Jan M; Marshall, Justin; Pix, Waltraud; Vorobyev, Misha; Zeil, Jochen

2006-10-01

Colour changes in fiddler crabs have long been noted, but a functional interpretation is still lacking. Here we report that neighbouring populations of Uca vomeris in Australia exhibit different degrees of carapace colours, which range from dull mottled to brilliant blue and white. We determined the spectral characteristics of the mud substratum and of the carapace colours of U. vomeris and found that the mottled colours of crabs are cryptic against this background, while display colours provide strong colour contrast for both birds and crabs, but luminance contrast only for a crab visual system. We tested whether crab populations may become cryptic under the influence of bird predation by counting birds overflying or feeding on differently coloured colonies. Colonies with cryptically coloured crabs indeed experience a much higher level of bird presence, compared to colourful colonies. We show in addition that colourful crab individuals subjected to dummy bird predation do change their body colouration over a matter of days. The crabs thus appear to modify their social signalling system depending on their assessment of predation risk.

Epizootiology of the parasitic dinoflagellate Hematodinium sp. in the American blue crab Callinectes sapidus.

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Messick, G A; Shields, J D

2000-11-14

Hematodinium sp. is a parasitic dinoflagellate that infects and kills blue crabs Callinectes sapidus. Periodic outbreaks of dinoflagellate infections with subsequent high host mortalities prompted a study of the epizootiology and distribution of the crab pathogen. Hemolymph samples from over 13000 crabs were assessed for infections over 8 yr. Moderate to high prevalences were found at several locations along the Atlantic and Gulf coasts of the United States. In the coastal bays of Maryland and Virginia, prevalence followed a seasonal pattern, with a sharp peak in late autumn. Infections were significantly more prevalent in crabs measuring less than 30 mm carapace width; host sex did not influence prevalence. Prevalences were highest in crabs collected from salinities of 26 to 30%o; no infected crabs were found in salinities below 11%o. Intensity of infection did not vary among crab sizes, molt stages, or sexes. Naturally and experimentally infected crabs died over 35 and 55 d in captivity, with a mean time to death of approximately 13 and 42 d, respectively. Several other crustaceans, including gammaridean amphipods, xanthid (mud) crabs, and the green crab Carcinus maenus, were found with Hematodinium-like infections. Considering its widespread distribution and high pathogenicity, we suggest that Hematodinium sp. represents a significant threat to blue crab populations in high salinity estuaries along the Atlantic and Gulf coasts of the USA.

Identification of genes associated with reproduction in the Mud Crab (Scylla olivacea and their differential expression following serotonin stimulation.

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Napamanee Kornthong

Full Text Available The central nervous system (CNS is often intimately involved in reproduction control and is therefore a target organ for transcriptomic investigations to identify reproduction-associated genes. In this study, 454 transcriptome sequencing was performed on pooled brain and ventral nerve cord of the female mud crab (Scylla olivacea following serotonin injection (5 µg/g BW. A total of 197,468 sequence reads was obtained with an average length of 828 bp. Approximately 38.7% of 2,183 isotigs matched with significant similarity (E value < 1e-4 to sequences within the Genbank non-redundant (nr database, with most significant matches being to crustacean and insect sequences. Approximately 32 putative neuropeptide genes were identified from nonmatching blast sequences. In addition, we identified full-length transcripts for crustacean reproductive-related genes, namely farnesoic acid o-methyltransferase (FAMeT, estrogen sulfotransferase (ESULT and prostaglandin F synthase (PGFS. Following serotonin injection, which would normally initiate reproductive processes, we found up-regulation of FAMeT, ESULT and PGFS expression in the female CNS and ovary. Our data here provides an invaluable new resource for understanding the molecular role of the CNS on reproduction in S. olivacea.

Cloning and characterisation of the SpToll gene from green mud crab, Scylla paramamosain.

Science.gov (United States)

Lin, Zhongyang; Qiao, Jie; Zhang, Yueling; Guo, Lingling; Huang, He; Yan, Fang; Li, Yuanyou; Wang, Xiuying

2012-05-01

Toll/Toll-like receptors (TLRs), one of the most important pattern recognition receptors (PRRs), play a crucial role in innate immune responses in both invertebrates and vertebrates. In this study, we cloned and characterised a Toll gene from Scylla paramamosain (SpToll). Bioinformatic analysis predicted that SpToll contained one open reading frame of 3018bp and encoded a single-pass transmembrane domain protein of 1005 amino acids. Further, SpToll could be clustered into one branch along with other arthropod Tolls in a phylogenetic tree. SpToll transcripts could be detected by RT-PCR from all tissues examined including the heart, gill, hepatopancreas, stomach, intestine, muscle, eyestalk and hemocytes. Infection by Vibrio parahemolyticus up-regulated SpToll mRNA expression in hemocytes after 48h. The profile of single nucleotide polymorphisms (SNPs) in the leucine-rich repeats (LRRs) domain of SpToll in three healthy crabs was then evaluated. Two hundred and twenty SNPs with a frequency of about 1.0-4.0% were identified in hemocyte DNA/cDNA. Surprisingly, the adenine to guanine transition at position 1372 (c.1372A>G) had a frequency of about 50%. Finally, the results showed that challenge with V. parahemolyticus stimulated the appearance of two sets of SNPs in crabs. More importantly, the c.1372A>G mutation could contribute to a low mortality after V. parahemolyticus infection and introduce variation of charge and secondary structure into the SpToll polypeptide. In summary, these studies suggested a novel Toll homologue in crab and identified a SNP with potential pathogen-resistant activities. The result will be important for the investigation of crab immune defense mechanisms. Copyright © 2011 Elsevier Ltd. All rights reserved.

Diversity and distribution of Dorippid Crabs (Brachyura: Dorippidae) in East Coast of Lampung, Indonesia

Science.gov (United States)

Zairion; Hakim, AA; Mashar, A.; Fahrudin, A.; Adrianto, L.; Widigdo, B.; Wardiatno, Y.

2018-05-01

Dorippid crabs (Brachyura: Dorippidae) commonly live in sand or mud substrate at shallow coastal water. These crabs are a macro-benthos, mostly found in tropic, have no economic value, but have high abundance in blue swimming crab habitat and lack information in Indonesia. This study aims to determine diversity and species distribution of dorippid crabs in East Coast of Lampung, Indonesia. This study was conducted on March-April 2017 in seven locations along coastal area (i.e. Labuhan Maringgai, Kuala Penet, Sekopong, Wako, Seputih, Sungai Burung, and Kuala Teladas). The specimen was collected from the blue swimming crab gill-net fishery as by-catch. Each location found by this family was noted at coordinate point at satellite imagery map and processed using ArcGIS. Two species have been found, there are Dorippe quadridens and Dorippoides facchino. Both species were found at every location, except D. quadridens at Sungai Burung as well as D. facchino in Sekopong. There are 74% among the sample of fishermen caught D. quadridens in those areas with an average number of 36 individuals and weight of 959 grams. While, 40% of fishermen caught D. facchino with an average number of 17 individuals and weight 152 grams.

Evolution of king crabs from hermit crab ancestors

Science.gov (United States)

Cunningham, C. W.; Blackstone, N. W.; Buss, L. W.

1992-02-01

KING crabs (Family Lithodidae) are among the world's largest arthropods, having a crab-like morphology and a strongly calcified exoskeleton1-6. The hermit crabs, by contrast, have depended on gastropod shells for protection for over 150 million years5,7. Shell-living has constrained the morphological evolution of hermit crabs by requiring a decalcified asymmetrical abdomen capable of coiling into gastropod shells and by preventing crabs from growing past the size of the largest available shells1-6. Whereas reduction in shell-living and acquisition of a crab-like morphology (carcinization) has taken place independently in several hermit crab lineages, and most dramatically in king crabs1-6, the rate at which this process has occurred was entirely unknown2,7. We present molecular evidence that king crabs are not only descended from hermit crabs, but are nested within the hermit crab genus Pagurus. We estimate that loss of the shell-living habit and the complete carcinization of king crabs has taken between 13 and 25 million years.

Genetic diversity and population structure of the endangered marsupial Sarcophilus harrisii (Tasmanian devil)

DEFF Research Database (Denmark)

Miller, Webb; Hayes, Vanessa M.; Ratan, Aakrosh

2011-01-01

The Tasmanian devil (Sarcophilus harrisii) is threatened with extinction because of a contagious cancer known as Devil Facial Tumor Disease. The inability to mount an immune response and to reject these tumors might be caused by a lack of genetic diversity within a dwindling population. Here we...... that the observed low genetic diversity in today's population preceded the Devil Facial Tumor Disease disease outbreak by at least 100 y. Using a genetically characterized breeding stock based on the genome sequence will enable preservation of the extant genetic diversity in future Tasmanian devil populations....

The mud crab Scylla serrata is one of the largest por- tunids and is ...

African Journals Online (AJOL)

denise

Indo-Pacific region. ... countries, the crab fisheries appear to be underdeveloped ... (1995) emphasized the importance of establishing ... Utende, Chole Island and Juani Island, Tanzania, and west of Quirimba and Ibo Island, ..... Asia. Mar. Biol. 128: 55–62. PAULY, D. 1995 — Anecdotes and the shifting baseline syndrome.

From oil-based mud to water-based mud

International Nuclear Information System (INIS)

Christiansen, C.

1991-01-01

Maersk Olie og Gas AS has used low toxic oil-based muds extensively since 1982 for drilling development wells and later in the development of horizontal well drilling techniques. However, in view of the strong drive towards a reduction in the amount of oil discharged to the North Sea from the oil industry, Maersk Olie og Gas AS initiated trials with new or improved types of water-based mud, first in deviated wells (1989) and then in horizontal wells (1990). The paper reviews Maersk Olie og Gas As experience with oil-based mud since the drilling of the first horizontal well in 1987, specifically with respect to cuttings washing equipment, oil retention on cuttings, and the procedure for monitoring of this parameter. It describes the circumstances leading to the decision to revert to water-based mud systems. Finally, it reviews the experience gained so far with the new improved types of water-based mud systems, mainly glycol and KCl/polymer mud systems. Comparison of operational data, such as rate of penetration, torque and drag, etc., is made between wells drilled with oil-based mud and water-based mud. The trials with the new improved types of water-based mud systems have been positive, i.e. horizontal wells can be drilled successfully with water-based mud. As a result, Maersk Olie og and Gas AS has decided to discontinue the use of low toxic oil-based muds in the Danish sector of the North Sea

Good Crab, Bad Crab

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Are crabs friends or foes of marsh grass, benefit or detriment to the salt marsh system? We examined Uca pugilator (sand fiddler) and Sesarma reticulatum (purple marsh crab) with Spartina patens (salt marsh hay) at two elevations (10 cm below MHW and 10 cm above MHW) in mesocosms...

Effectiveness of artificial diet enriched by spinach extract on molting stimulation to produce soft shell crab

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Siti Aslamyah

2011-01-01

Full Text Available Artificial feed is an alternative media applications spinach extract (EB that is known to contain molting stimulant. However, utilization of the artificial feed is related to its expensive cost, with a very high protein concentration since it's mainly produced from fish based materials, so need to be studied artificial feed formulation with substitution of vegetable material in stimulating molting and growth of mud crabs. Four formula artificial feed enriched EB (700 ng/g crab used in this study were feed A (fish, crab shells, and cassava, feed B (fish, silage, shell crab, and cassava, feed C (fish, silage, shell crab, soy flour, and cassava, and feed D (fish, silage, shell crab, soy flour, corn starch, and pollard, trash fish and feed A without EB as control. During the test, mud crab intermolt phase was culture individually in crab box placed in pond. The results showed that the percentage of molting and weight growth in their respective in the feed A (44% and 41.96%; feed B (56% and 31.57%; feed C (74% and 23.20%; feed D (50% and 39.15%; trash feed control (24% and 50.66%; and feed A without EB (28% and 35.11%. An opposite phenomenon, where the feed C with the highest percentage of molting but with the lowest growth rate, the opposite occurs in the control of trash feed. This is apparently the effect of spinach extract as a stimulant molting, where performance can be optimized with a complete and balance nutrient composition. This prediction is supported by the analysis of protein content of crabs tested at the highest feed C treatment compared with the control feed. Key words: spinach extract, soft shell crab, molting, artificial feed, growth   ABSTRAK Pakan buatan merupakan alternatif media aplikasi ekstrak bayam (EB yang diketahui mengandung stimulan molting.  Namun demikian, pakan buatan yang digunakan masih mahal dengan kandungan protein yang tinggi, karena berbahan dasar ikan, sehingga perlu dikaji formulasi pakan buatan dengan

Behavioural Response Thresholds in New Zealand Crab Megalopae to Ambient Underwater Sound

Science.gov (United States)

Stanley, Jenni A.; Radford, Craig A.; Jeffs, Andrew G.

2011-01-01

A small number of studies have demonstrated that settlement stage decapod crustaceans are able to detect and exhibit swimming, settlement and metamorphosis responses to ambient underwater sound emanating from coastal reefs. However, the intensity of the acoustic cue required to initiate the settlement and metamorphosis response, and therefore the potential range over which this acoustic cue may operate, is not known. The current study determined the behavioural response thresholds of four species of New Zealand brachyuran crab megalopae by exposing them to different intensity levels of broadcast reef sound recorded from their preferred settlement habitat and from an unfavourable settlement habitat. Megalopae of the rocky-reef crab, Leptograpsus variegatus, exhibited the lowest behavioural response threshold (highest sensitivity), with a significant reduction in time to metamorphosis (TTM) when exposed to underwater reef sound with an intensity of 90 dB re 1 µPa and greater (100, 126 and 135 dB re 1 µPa). Megalopae of the mud crab, Austrohelice crassa, which settle in soft sediment habitats, exhibited no response to any of the underwater reef sound levels. All reef associated species exposed to sound levels from an unfavourable settlement habitat showed no significant change in TTM, even at intensities that were similar to their preferred reef sound for which reductions in TTM were observed. These results indicated that megalopae were able to discern and respond selectively to habitat-specific acoustic cues. The settlement and metamorphosis behavioural response thresholds to levels of underwater reef sound determined in the current study of four species of crabs, enables preliminary estimation of the spatial range at which an acoustic settlement cue may be operating, from 5 m to 40 km depending on the species. Overall, these results indicate that underwater sound is likely to play a major role in influencing the spatial patterns of settlement of coastal crab

Factors controlling mud accumulation in the Heuksan mud belt off southwestern Korea

Science.gov (United States)

Chang, Tae Soo; Ha, Hun Jun; Chun, Seung Soo

2015-12-01

The Heuksan mud belt (hereafter HMB) is 20~50 km wide, ~200 km long, and ~50 m thick, having accumulated in the course of the Holocene transgression on the tide-dominated epicontinental shelf southwest of Korea. The internal architecture of the HMB is characterized by offshore prograding clinoforms. Of particular interest are the depositional processes responsible for this anomalously thick mud accumulation within a relatively short period of time. Tidal currents are important in the dispersal of mud in the HMB, although these alone cannot explain such an enormous mud deposit. In order to understand the formative processes of the HMB, a detailed sedimentary facies analysis, including high-resolution grain-size measurements, has been conducted on more than 30 short cores and three long drill cores recovered from the mud belt. Five major mud facies were identified. Of these, mud sequences showing a thickening-thinning trend of alternating silt and clay laminae suggestive of a tidal origin occur dominantly at inner to mid shelf locations. By contrast, internally structureless muds with sharp bases and no bioturbation, which are interpreted of representing fluid-mud deposits, are widespread at mid to outer shelf locations. Wave-generated mud ripples and storm beds on the inner shelf suggest that storm waves in winter resuspend previously deposited mud to form near-bed fluid-mud suspensions with resulting gravity-driven mud transport across the low-gradient outer shelf. This previously not recognized process is probably a major factor controlling depositional processes on the giant mud belt, enabling rapid accumulation and offshore progradation even during transgression, i.e., at times of sea-level rise.

UJI PERBEDAAN SALINITAS TERHADAP DAYA TETAS TELUR (Hatching Rate KEPITING BAKAU (Scylla serrata

Directory of Open Access Journals (Sweden)

Budi Mulyawan

2010-10-01

Full Text Available Mud crabs (Scylla sp. is one of marine commodities that is profitable. Mangrove crabs are able to hatch and breed within large variety of salinity. One of the main factors affecting hatching rate and also breeding is salinity. This research is aimed to know the effect of salinity to hatching rate of mud crabs. The design used was complete random sampling through three treatments: those are 15%o, 25%o and 30%o with 3 repetitions. Result of this research shows that hatching rate of mud crabs is affected by salinity. Treatment B (25 %o is significantly different with treatment A (15%o and C (30%o. The most appropriate hatching condition is gained from treatment B with average value 91.8%.Keywords: mud crab, Scylla sp, mangroves

Use of multiple chemical tracers to define habitat use of Indo-Pacific mangrove crab, Scylla serrata (Decapoda: Portunidae)

Science.gov (United States)

Demopoulos, A.W.J.; Cormier, N.; Ewel, K.C.; Fry, B.

2008-01-01

The mangrove or mud crab, Scylla serrata, is an important component of mangrove fisheries throughout the Indo-Pacific. Understanding crab diets and habitat use should assist in managing these fisheries and could provide additional justification for conservation of the mangrove ecosystem itself. We used multiple chemical tracers to test whether crab movements were restricted to local mangrove forests, or extended to include adjacent seagrass beds and reef flats. We sampled three mangrove forests on the island of Kosrae in the Federated States of Micronesia at Lelu Harbor, Okat River, and Utwe tidal channel. Samples of S. serrata and likely food sources were analyzed for stable carbon (??13C), nitrogen (??15N), and sulfur (??34S) isotopes. Scylla serrata tissues also were analyzed for phosphorus (P), cations (K, Ca, Mg, Na), and trace elements (Mn, Fe, Cu, Zn, and B). Discriminant analysis indicated that at least 87% of the crabs remain in each site as distinct populations. Crab stable isotope values indicated potential differences in habitat use within estuaries. Values for ??13C and ??34S in crabs from Okat and Utwe were low and similar to values expected from animals feeding within mangrove forests, e.g., feeding on infauna that had average ??13C values near -26.5???. In contrast, crabs from Lelu had higher ?? 13C and ??34S values, with average values of -21.8 and 7.8???, respectively. These higher isotope values are consistent with increased crab foraging on reef flats and seagrasses. Given that S. serrata have been observed feeding on adjacent reef and seagrass environments on Kosrae, it is likely that they move in and out of the mangroves for feeding. Isotope mixing model results support these conclusions, with the greatest mangrove ecosystem contribution to S. serrata diet occurring in the largest mangrove forests. Conserving larger island mangrove forests (> 1 km deep) appears to support crab foraging activities. ?? 2007 Coastal and Estuarine Research

Occurrence of Pasteurellaceae bacteria in the oral cavity of the Tasmanian devil (Sarcophilus harrisii)

DEFF Research Database (Denmark)

Brix, Lena; Hansen, Mie Johanne; Kelly, Androo

2015-01-01

The occurrence of bacteria belonging to the family Pasteurellaceae in the oral cavity of captive Tasmanian devils (Sarcophilus harrisii) was investigated using phenotypic and subsequent genotypic characterization and phylogenetic analyses. A total of 62 bacterial isolates obtained from Tasmanian...... devils, tentatively classified with the family Pasteurellaceae, were further characterized by phylogenetic analysis of rpoB gene sequence similarity, which showed that the isolates investigated formed five distinct groups. A total of 15 strains formed a novel genus-like group within Pasteurellaceae...... with a 100% rpoB similarity with Pasteurella dagmatis. Finally, a single strain showed 97.1% resemblance to Haemophilus haemoglobinophilus. The results demonstrate that Tasmanian devils are hosting a variety of bacterial taxa affiliated with the family of Pasteurellaceae as part of their oral microflora....

Discovery of Maritrema jebuensis n. sp. (Digenea: Microphallidae) from the Asian Shore Crab, Hemigrapsus sanguineus, in Korea.

Science.gov (United States)

Chung, Ok-Sik; Lee, Hye-Jung; Sohn, Woon-Mok; Lee, Seung-Ha; Park, Il-Yong; Oh, Sang-Ah; Chai, Jong-Yil; Seo, Min

2010-12-01

Maritrema spp. (Digenea: Microphallidae) are parasites of birds, but have not been found in the Republic of Korea. In this study, metacercariae of Maritrema sp. were discovered in the Asian shore crab, Hemigrapsus sanguineus, caught in the mud-flats of Jebu-do, Hwasung-gun, Gyeonggi-do, and the adult flukes were confirmed by experimental infection into mice. Based on the symmetric ribbon-like vitellarium, adult flukes of Maritrema sp. were identified, but did not belong to previously described species in terms of the following morphologic characteristics: ceca reaching to the lateral wall at the anterior border of the ovary; ventral sucker larger than oral sucker; a prominent metraterm; and vitellarium forming a complete ring. Hence, we named this microphallid M. jebuensis n. sp. after the island where the second intermediate hosts were collected. From this study, it has been shown that Maritrema sp. is distributed in Korea and transmitted by the Asian shore crab, H. sanguineus.

Drilling mud

Energy Technology Data Exchange (ETDEWEB)

Rusayev, A A; Bibikov, K V; Simonenkov, I D; Surkova, K I

1982-01-01

Drilling mud is proposed which contains clay, water, water output reducer, pH regulator, viscosity reducer and hydrogen sulfide absorber. In order to improve the absorbing capacity of the drilling mud with pH 8-11 and simultaneously preservation of the technological properties of the mud, it contains as the absorber of hydrogen sulfide pyrite cinders with the following ratio of components, % by mass: clay 5.0-35.0; water output reducer 0.2-2.0; pH regulator 0.05-0.25; viscosity reducer 0.1-1.0; pyrite cinders 0.5-4.0; water--the rest.

Drilling mud

Energy Technology Data Exchange (ETDEWEB)

Baranovskiy, V D; Brintsev, A I; Gusev, V G; Katenev, Ye P; Pokhorenko, I V

1979-10-25

A drilling mud is proposed, which contains a dispersion medium, a dispersion phase, for instance, clay, a stabilizer reagent, for instance, carboxymethylcellulose and a weighter. In order to reduce the viscosity and to increase the stability of the mud it contains as the dispersion medium a 75% aqueous solution of the L-7 reagent. To increase the salt resistance of the mud, it additionally contains sodium chloride in a volume of 4.04.5 percent by weight, and to regulate the alkalinity, it additionally contains sodium hydroxide in a volume of 1.1 to 1.3 percent by weight.

Numerical simulation of mud erosion rate in sand-mud alternate layer and comparison with experiment

Science.gov (United States)

Yoshida, T.; Yamaguchi, T.; Oyama, H.; Sato, T.

2015-12-01

For gas production from methane hydrates in sand-mud alternate layers, depressurization method is expected as feasible. After methane hydrate is dissociated, gas and water flow in pore space. There is a concern about the erosion of mud surface and it may result in flow blockage that disturbs the gas production. As a part of a Japanese National hydrate research program (MH21, funded by METI), we developed a numerical simulation of water-induced mud erosion in pore-scale sand-mud domains to model such mud erosion. The size of which is of the order of 100 micro meter. Water flow is simulated using a lattice Boltzmann method (LBM) and mud surface is treated as solid boundary with arbitrary shape, which changes with time. Periodic boundary condition is adopted at the domain boundaries, except for the surface of mud layers and the upper side. Shear stress acting on the mud surface is calculated using a momentum-exchange method. Mud layer is eroded when the shear stress exceeds a threshold coined a critical shear stress. In this study, we compared the simulated mud erosion rate with experimental data acquired from an experiment using artificial sand-mud core. As a result, the simulated erosion rate agrees well with that of the experiment.

The Crab Nebula

International Nuclear Information System (INIS)

Mitton, S.

1979-01-01

The subject is covered in chapters, as follows: A.D.1054, a star explodes (historical account of observations of the supernova of which the Crab Nebula is the remnant); the telescope takes over (discovery and subsequent observation of the Crab Nebula); the message of the fiery remnant (detailed structure and its interpretation); the invisible nebula (electromagnetic radiation from the Crab Nebula and its interpretation); a beacon in the night (the discovery of pulsars, with special reference to the pulsar in the Crab Nebula; observation and theory); the strange world of a neutron star (theory, prediction and observation); magnetic fields and energy flow from the pulsar (stellar magnetosphere; luminosity of the nebula); how does the pulsar pulse (observation; models to explain beaming); outburst and aftermath (types of supernovae and their evolution; nucleosynthesis); supernovae and their remnants (account of observations since early records); the Crab Nebula and modern astronomy. (U.K.)

Chesapeake Bay Future Conditions Report. Volume 11. Biota.

Science.gov (United States)

1977-12-01

vertebrates , the cattle egret , glossy ibis and nutr ia are highly success ful new- comers , with an ecological impact yet to be assessed. Eurasian wa...Horned grebe Podiceps aur i tus Protected Cattle egret Bubulcus ibis Protected Great blue heron Ardea herodias Protected Glossy ibis Plegadis...xanthid crabs but not R. harrisii. Non-nutritional Role of Other Species Fertilization: Loxothylacus castrates the sexual organs. Appendix 15 119

Multi-Sensor Mud Detection

Science.gov (United States)

Rankin, Arturo L.; Matthies, Larry H.

2010-01-01

Robust mud detection is a critical perception requirement for Unmanned Ground Vehicle (UGV) autonomous offroad navigation. A military UGV stuck in a mud body during a mission may have to be sacrificed or rescued, both of which are unattractive options. There are several characteristics of mud that may be detectable with appropriate UGV-mounted sensors. For example, mud only occurs on the ground surface, is cooler than surrounding dry soil during the daytime under nominal weather conditions, is generally darker than surrounding dry soil in visible imagery, and is highly polarized. However, none of these cues are definitive on their own. Dry soil also occurs on the ground surface, shadows, snow, ice, and water can also be cooler than surrounding dry soil, shadows are also darker than surrounding dry soil in visible imagery, and cars, water, and some vegetation are also highly polarized. Shadows, snow, ice, water, cars, and vegetation can all be disambiguated from mud by using a suite of sensors that span multiple bands in the electromagnetic spectrum. Because there are military operations when it is imperative for UGV's to operate without emitting strong, detectable electromagnetic signals, passive sensors are desirable. JPL has developed a daytime mud detection capability using multiple passive imaging sensors. Cues for mud from multiple passive imaging sensors are fused into a single mud detection image using a rule base, and the resultant mud detection is localized in a terrain map using range data generated from a stereo pair of color cameras.

What regulates crab predation on mangrove propagules?

Science.gov (United States)

Van Nedervelde, Fleur; Cannicci, Stefano; Koedam, Nico; Bosire, Jared; Dahdouh-Guebas, Farid

2015-02-01

Crabs play a major role in some ecosystems. To increase our knowledge about the factors that influence crab predation on propagules in mangrove forests, we performed experiments in Gazi Bay, Kenya in July 2009. We tested whether: (1) crab density influences propagule predation rate; (2) crab size influences food competition and predation rate; (3) crabs depredate at different rates according to propagule and canopy cover species; (4) vegetation density is correlated with crab density; (5) food preferences of herbivorous crabs are determined by size, shape and nutritional value. We found that (1) propagule predation rate was positively correlated to crab density. (2) Crab competitive abilities were unrelated to their size. (3) Avicennia marina propagules were consumed more quickly than Ceriops tagal except under C. tagal canopies. (4) Crab density was negatively correlated with the density of A. marina trees and pneumatophores. (5) Crabs prefer small items with a lower C:N ratio. Vegetation density influences crab density, and crab density affects propagule availability and hence vegetation recruitment rate. Consequently, the mutual relationships between vegetation and crab populations could be important for forest restoration success and management.

Physical and Chemical Properties of Sintering Red Mud and Bayer Red Mud and the Implications for Beneficial Utilization

Science.gov (United States)

Wang, Ping; Liu, Dong-Yan

2012-01-01

Performances of two common types of red mud, Bayer red mud and Sintering red mud, were investigated in this research. Their compositions, mechanical properties and microstructure characterization were measured through XRD, TG and SEM analysis. Their shear strength, particle size, density and hydraulic characteristics also had been performed. Huge differences between the basic mineral types of these two kinds of red mud also can be found. The comparison of compositions shows that CaCO3 content in Sintering red mud is higher, Bayer red mud has more hazardous elements such as As, Pb and Hg and both have a high concentration of radioactivity. The micro particle of Bayer red mud is finer and more disperse, but the Sintering red mud has higher shear strength. Combining the TG and hydraulic characteristics analysis, it can be shown that Bayer red mud has higher value of water content and Sintering red mud has higher hydraulic conductivity. The paper then illustrates that Sintering red mud can become the main filling material of supporting structure of red mud stocking yard. Bayer red mud has a high reuse value and also can be used as a mixing material of masonry mortar.

Isolation and characterization of the metamorphic inducer of the common mud crab, Panopeus herbstii.

Science.gov (United States)

Andrews, W R.; Targett, N M.; Epifanio, C E.

2001-06-15

Several items from the natural habitat of adult Panopeus herbstii were examined to determine if they had the ability to produce a metamorphic cue. These included adult conspecifics, natural rock/shell substratum, the co-occurring species Hemigrapsus sanguineus and bacterial biofilms. Adult conspecifics, H. sangineus and natural rock/shell all accelerated metamorphosis. However, adult conspecifics accelerated metamorphosis to the greatest extent. The cue associated with adult conspecifics was found to be water-soluble, stable following boiling and freezing, and of relatively small molecular size (<1 kDa). Furthermore, the cue appears to be produced from the conspecifics themselves, rather than from biofilms colonizing the surfaces of the crabs. The results of this experiment suggest that postlarvae of P. herbstii are able to distinguish suitable habitat through chemical signals, thus greatly increasing their chances for survival.

Shallow-Water Mud Acoustics

Science.gov (United States)

2015-09-30

1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Shallow-Water Mud Acoustics William L. Siegmann...models and methods that explain observed material and acoustic properties of different physical types of shallow-ocean mud sediments. Other goals...are to assess prior data relating to the acoustic properties of mud and to provide guidance in the development and interpretation of experiments. A

Convolutional neural network guided blue crab knuckle detection for autonomous crab meat picking machine

Science.gov (United States)

Wang, Dongyi; Vinson, Robert; Holmes, Maxwell; Seibel, Gary; Tao, Yang

2018-04-01

The Atlantic blue crab is among the highest-valued seafood found in the American Eastern Seaboard. Currently, the crab processing industry is highly dependent on manual labor. However, there is great potential for vision-guided intelligent machines to automate the meat picking process. Studies show that the back-fin knuckles are robust features containing information about a crab's size, orientation, and the position of the crab's meat compartments. Our studies also make it clear that detecting the knuckles reliably in images is challenging due to the knuckle's small size, anomalous shape, and similarity to joints in the legs and claws. An accurate and reliable computer vision algorithm was proposed to detect the crab's back-fin knuckles in digital images. Convolutional neural networks (CNNs) can localize rough knuckle positions with 97.67% accuracy, transforming a global detection problem into a local detection problem. Compared to the rough localization based on human experience or other machine learning classification methods, the CNN shows the best localization results. In the rough knuckle position, a k-means clustering method is able to further extract the exact knuckle positions based on the back-fin knuckle color features. The exact knuckle position can help us to generate a crab cutline in XY plane using a template matching method. This is a pioneering research project in crab image analysis and offers advanced machine intelligence for automated crab processing.

Limb regeneration and molting processes under chronic methoprene exposure in the mud fiddler crab, Uca pugnax.

Science.gov (United States)

Stueckle, Todd A; Likens, Jason; Foran, Christy M

2008-04-01

Insect growth regulator application for wetland mosquito control remains controversial due to the potential for disruption of normal development and growth processes in non-target crustaceans and beneficial arthropods, e.g. Apis mellifera. Concerns include slow-release methoprene formulations and its environmental breakdown products which mimic an endogenous crustacean hormone and retinoids, respectively. Our primary objective was to evaluate the effect that a chronic methoprene exposure would have on male and female Uca pugnax limb regeneration and molting. After single limb autonomy, limb growth and molt stage were monitored every two days while eyestalk ablation was used to induce proecdysis. Dorsal carapace was collected 6 days post-molt to determine protein and chitin content. In post-molt crabs, methoprene-exposed individuals displayed lower percent gain in body weight. Male crabs lost more weight per body volume than females, took significantly longer to proceed through proecdysis than females exposed to 0.1 microg/L methoprene and exhibited significantly elevated frequency for abnormal limb formation at 1.0 microg/L while females displayed no such trend. Methoprene did not significantly alter extractable exoskeleton protein or chitin content. However, variable water-soluble protein expression increased with exposure at 1.0 microg/L (1 ppb) which contributed to overall variability in total protein content. Our findings suggest that adult male U. pugnax possess greater sensitivity to chronic methoprene exposure during limb regeneration and molting, potentially affecting their post-molt fitness. Furthermore, methoprene has the potential to impact post-molt biomass and exocuticle quality.

Newly identified invertebrate-type lysozyme (Splys-i) in mud crab (Scylla paramamosain) exhibiting muramidase-deficient antimicrobial activity.

Science.gov (United States)

Zhou, Jian; Zhao, Shu; Fang, Wen-Hong; Zhou, Jun-Fang; Zhang, Jing-Xiao; Ma, Hongyu; Lan, Jiang-Feng; Li, Xin-Cang

2017-09-01

Lysozymes are widely distributed immune effectors exerting muramidase activity against the peptidoglycan of the bacterial cell wall to trigger cell lysis. However, some invertebrate-type (i-type) lysozymes deficient of muramidase activity still exhibit antimicrobial activity. To date, the mechanism underlying the antimicrobial effect of muramidase-deficient i-type lysozymes remains unclear. Accordingly, this study characterized a novel i-type lysozyme, Splys-i, in the mud crab Scylla paramamosain. Splys-i shared the highest identity with the Litopenaeus vannamei i-type lysozyme (Lvlys-i2, 54% identity) at the amino acid level. Alignment analysis and 3D structure comparison show that Splys-i may be a muramidase-deficient i-type lysozyme because it lacks the two conserved catalytic residues (Glu and Asp) that are necessary for muramidase activity. Splys-i is mainly distributed in the intestine, stomach, gills, hepatopancreas, and hemocytes, and it is upregulated by Vibrio harveyi or Staphylococcus aureus challenge. Recombinant Splys-i protein (rSplys-i) can inhibit the growth of Gram-negative bacteria (V. harveyi, Vibrio alginolyticus, Vibrio parahemolyticus, and Escherichia coli), Gram-positive bacteria (S. aureus, Bacillus subtilis, and Bacillus megaterium), and the fungus Candida albicans to varying degrees. In this study, two binding assays and a bacterial agglutination assay were conducted to elucidate the potential antimicrobial mechanisms of Splys-i. Results demonstrated that rSplys-i could bind to all nine aforementioned microorganisms. It also exhibited a strong binding activity to lipopolysaccharide from E. coli and lipoteichoic acid and peptidoglycan (PGN) from S. aureus but a weak binding activity to PGN from B. subtilis and β-glucan from fungi. Moreover, rSplys-i could agglutinate these nine types of microorganisms in the presence of Ca 2+ at different protein concentrations. These results suggest that the binding activity and its triggered

Fishery characteristics and abundance estimates of the mangrove ...

African Journals Online (AJOL)

The mud crab Scylla serrata is lightly exploited along the East African seaboard. This study reports on fishing practices and gives preliminary estimates of abundance and size structures of the mud crab populations in Utende, Chole Island and Juani Island, Tanzania, and west of Quirimba and Ibo Island, Moçambique.

Crab cavities for linear colliders

CERN Document Server

Burt, G; Carter, R; Dexter, A; Tahir, I; Beard, C; Dykes, M; Goudket, P; Kalinin, A; Ma, L; McIntosh, P; Shulte, D; Jones, Roger M; Bellantoni, L; Chase, B; Church, M; Khabouline, T; Latina, A; Adolphsen, C; Li, Z; Seryi, Andrei; Xiao, L

2008-01-01

Crab cavities have been proposed for a wide number of accelerators and interest in crab cavities has recently increased after the successful operation of a pair of crab cavities in KEK-B. In particular crab cavities are required for both the ILC and CLIC linear colliders for bunch alignment. Consideration of bunch structure and size constraints favour a 3.9 GHz superconducting, multi-cell cavity as the solution for ILC, whilst bunch structure and beam-loading considerations suggest an X-band copper travelling wave structure for CLIC. These two cavity solutions are very different in design but share complex design issues. Phase stabilisation, beam loading, wakefields and mode damping are fundamental issues for these crab cavities. Requirements and potential design solutions will be discussed for both colliders.

Crab Rationalization Permit Program

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Crab Rationalization Program (Program) allocates BSAI crab resources among harvesters, processors, and coastal communities. The North Pacific Fishery Management...

40 CFR 230.42 - Mud flats.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Mud flats. 230.42 Section 230.42... Aquatic Sites § 230.42 Mud flats. (a) Mud flats are broad flat areas along the sea coast and in coastal rivers to the head of tidal influence and in inland lakes, ponds, and riverine systems. When mud flats...

The anatomy of the king crab Hapalogaster mertensii Brandt, 1850 (Anomura: Paguroidea: Hapalogastridae): new insights into the evolutionary transformation of hermit crabs into king crabs

NARCIS (Netherlands)

Keiler, J.; Richter, S.; Wirkner, C.S.

2015-01-01

The emergence of king crabs from a hermit crab-like ancestor is one of the most curious events in decapod evolution. King crabs comprise two taxa, Lithodidae and Hapalogastridae, and while lithodids have formed the focus of various anatomical studies, the internal anatomy of hapalogastrids has never

Thermal Mud Molecular Overview

Directory of Open Access Journals (Sweden)

Ersin Odabasi

2014-06-01

Full Text Available Thermal mud (peloids, which are frequently used for thermal therapy purposes consist of organic and inorganic (minerals compounds in general. Organic structure is formed after a variety of chemical processes occurring in decades and comprise of a very complex structure. Stagnant water environment, herbal diversity, microorganism multiplicity and time are crucial players to form the structure. Data regarding description of organic compounds are very limited. Nowadays, it was clearly understood that a variety of compounds those are neglected in daily practice are found in thermal mud after GC-MS and similar methods are being frequently used. Those compounds which are biologically active are humic compounds, carboxylic acids, terpenoids, steroids and fatty acids. By comprising the thermal mud, these different compound groups which are related to divers areas from cosmetology to inflammation, make the thermal mud very meaningful in the treatment of human disease. In this review, it was tried to put forward the effects of several molecule groups those consisting of the thermal mud structure. [TAF Prev Med Bull 2014; 13(3.000: 257-264

Grooming behaviors and gill fouling in the commercially important blue crab (Callinectes sapidus and stone crab (Menippe mercenaria

Directory of Open Access Journals (Sweden)

Jen L. Wortham

2017-10-01

Full Text Available Abstract Grooming behaviors reduce fouling of body regions. In decapods, grooming time budgets, body regions groomed, and grooming appendages are known in several species; however, little data exists on brachyuran crabs. In this study, grooming behaviors of two commercially important crabs were documented (blue crabs: Callinectes sapidus Rathbun, 1896; stone crabs: Menippe mercenaria Say, 1818. These crabs are harvested by fishermen and knowing their grooming behaviors is valuable, as clean crabs are preferred by consumers and the stone crab fishery consequence of removing one cheliped to grooming behaviors is unknown. Crabs were observed individually and agonistically to determine how grooming behaviors vary in the presence of another conspecific. Both species frequently use their maxillipeds and groom, with the gills being cleaned by epipods. Respiratory and sensory structures were groomed frequently in both species. Removal of a grooming appendage resulted in higher fouling levels in the gills, indicating that grooming behaviors do remove fouling. Overall, stone crabs had a larger individual time budget for grooming, but agonistic grooming time budgets were similar. Stone crab chelipeds are used in grooming, especially cleaning the other cheliped. The chelipeds are not the main grooming appendage; however, implications of losing one cheliped may have large impacts.

Ecomorphology of crabs and swimming crabs (Crustacea DecapodaBrachyura from coastal ecosystems

Directory of Open Access Journals (Sweden)

Murilo Zanetti Marochi

Full Text Available Abstract Brachyuran crabs are one of the most diverse taxa of crustaceans, occurring in almost all coastal habitats. Due to their high morphological diversification, the authors sought to ascertain the existence of morphological patterns related to the habitat of coastal brachyuran crabs. We analyzed 17 species from mangrove forests, rocky shores, sandy beaches and exclusively aquatic marine/estuarine ecosystems. A total of 16 linear measurements of males and 17 of females were obtained for each habitat. We were able to discriminate three functional groups of crab species, based on their habitat: 1. Complex Substrates, 2. Semiterrestrial, 3. Exclusively Aquatic. The species belonging to the Complex Substrates group had long ambulatory legs, as well as being heteroquely related to uneven terrain. Semiterrestrial species showed ambulatory legs of different sizes, allowing them to walk easily on the terrestrial terrain due to the long fourth ambulatory leg, and long eyestalks which are important for visual communication. Exclusively Aquatic species showed the largest carapace widths and the shortest eyestalks. The presence of different crab lineages in the environments analyzed allows us to demonstrate the clear evolutionary convergence, by which the crabs adapted to their specific habitat and environment.

Effects of urban wastewater on crab and mollusc assemblages in equatorial and subtropical mangroves of East Africa

Science.gov (United States)

Cannicci, Stefano; Bartolini, Fabrizio; Dahdouh-Guebas, Farid; Fratini, Sara; Litulo, Carlos; Macia, Adriano; Mrabu, Elisha J.; Penha-Lopes, Gil; Paula, José

2009-09-01

Mangrove forests are known to accomplish crucial ecosystem functions and services. They are nursery areas for fish, prawns and crabs, which provide coastal communities with a variety of food, timber and chemicals, and protect coasts from catastrophic events, such as tsunamis. Recently, a novel ecological service has been proposed for mangrove systems, namely natural wastewater treatment wetlands. This hypothesis was based on experimental data collected mainly in Chinese mangrove systems, which proved that mangrove soils were efficient in absorbing nutrients. Moreover, sewage loading seemed harmless to both plants and benthic communities in these systems. However, before promoting the use of natural mangroves as pollution buffers, or constructed mangrove wetlands as sewage treatment facilities, more data are needed on their overall tolerance to organic loading. Differences in macrobenthos patterns were thus investigated between peri-urban mangroves and sites not affected by sewage disposal in East Africa. We assessed differences in epifaunal assemblages, comprising crabs and molluscs, employing multivariate ACI unbalanced analyses to compare peri-urban mangrove swamps with those characteristic of non-urban mangroves with similar ecological traits. The sampling design was spatially nested, replicates being assessed at equatorial (southern Kenya) and subtropical (southern Mozambique) sites. The results manifested a consistent increase in crab biomass at the peri-urban sites in both Kenya and Mozambique. Moreover, the peri-urban systems were richer than the non-urban mangroves, both in terms of fiddler crabs ( Uca spp.) which feed on benthic microalgae and bacteria, and sesarmids, such as Perisesarma guttatum and Neosarmatium meinerti, which feed on both substratum and leaf litter. The abundance of gastropods, in contrast, decreased significantly, especially in Kenya, mainly due to the disappearance of the mud whelk Terebralia palustris. The results thus indicate that

Multiphase modelling of mud volcanoes

Science.gov (United States)

Colucci, Simone; de'Michieli Vitturi, Mattia; Clarke, Amanda B.

2015-04-01

Mud volcanism is a worldwide phenomenon, classically considered as the surface expression of piercement structures rooted in deep-seated over-pressured sediments in compressional tectonic settings. The release of fluids at mud volcanoes during repeated explosive episodes has been documented at numerous sites and the outflows resemble the eruption of basaltic magma. As magma, the material erupted from a mud volcano becomes more fluid and degasses while rising and decompressing. The release of those gases from mud volcanism is estimated to be a significant contributor both to fluid flux from the lithosphere to the hydrosphere, and to the atmospheric budget of some greenhouse gases, particularly methane. For these reasons, we simulated the fluid dynamics of mud volcanoes using a newly-developed compressible multiphase and multidimensional transient solver in the OpenFOAM framework, taking into account the multicomponent nature (CH4, CO2, H2O) of the fluid mixture, the gas exsolution during the ascent and the associated changes in the constitutive properties of the phases. The numerical model has been tested with conditions representative of the LUSI, a mud volcano that has been erupting since May 2006 in the densely populated Sidoarjo regency (East Java, Indonesia), forcing the evacuation of 40,000 people and destroying industry, farmland, and over 10,000 homes. The activity of LUSI mud volcano has been well documented (Vanderkluysen et al., 2014) and here we present a comparison of observed gas fluxes and mud extrusion rates with the outcomes of numerical simulations. Vanderkluysen, L.; Burton, M. R.; Clarke, A. B.; Hartnett, H. E. & Smekens, J.-F. Composition and flux of explosive gas release at LUSI mud volcano (East Java, Indonesia) Geochem. Geophys. Geosyst., Wiley-Blackwell, 2014, 15, 2932-2946

LHC crab-cavity aspects and strategy

International Nuclear Information System (INIS)

Calaga, R.; Tomas, R.; Zimmermann, F.

2010-01-01

The 3rd LHC Crab Cavity workshop (LHC-CC09) took place at CERN in October 2009. It reviewed the current status and identified a clear strategy towards a future crab-cavity implementation. Following the success of crab cavities in KEK-B and the strong potential for luminosity gain and leveling, CERN will pursue crab crossing for the LHC upgrade. We present a summary and outcome of the variousworkshop sessions which have led to the LHC crab-cavity strategy, covering topics like layout, cavity design, integration, machine protection, and a potential validation test in the SPS.

Perceptions of environmental changes and Lethargic crab disease among crab harvesters in a Brazilian coastal community

Science.gov (United States)

2011-01-01

Background Lethargic Crab Disease (LCD) has caused significant mortalities in the population of Ucides cordatus crabs in the Mucuri estuary in Bahia State, Brazil, and has brought social and economic problems to many crab-harvesting communities that depend on this natural resource. The present work examined the perceptions of members of a Brazilian crab harvesting community concerning environmental changes and the Lethargic Crab Disease. Methods Field work was undertaken during the period between January and April/2009, with weekly or biweekly field excursions during which open and semi-structured interviews were held with local residents in the municipality of Mucuri, Bahia State, Brazil. A total of 23 individuals were interviewed, all of whom had at least 20 years of crab-collecting experience in the study region. Key-informants (more experienced crab harvesters) were selected among the interviewees using the "native specialist" criterion. Results According to the collectors, LCD reached the Mucuri mangroves between 2004 and 2005, decimating almost all crab population in the area, and in 2007, 2008 and 2009 high mortalities of U. cordatus were again observed as a result of recurrences of this disease in the region. In addition to LCD, crabs were also suffering great stock reductions due to habitat degradation caused by deforestation, landfills, sewage effluents, domestic and industrial wastes and the introduction of exotic fish in the Mucuri River estuary. The harvesting community was found to have significant ecological knowledge about the functioning of mangrove swamp ecology, the biology of crabs, and the mass mortality that directly affected the economy of this community, and this information was largely in accordance with scientific knowledge. Conclusions The study of traditional knowledge makes it possible to better understand human interactions with the environment and aids in the elaboration of appropriate strategies for natural resource conservation

Perceptions of environmental changes and Lethargic crab disease among crab harvesters in a Brazilian coastal community

Directory of Open Access Journals (Sweden)

Firmo Angélica MS

2011-11-01

Full Text Available Abstract Background Lethargic Crab Disease (LCD has caused significant mortalities in the population of Ucides cordatus crabs in the Mucuri estuary in Bahia State, Brazil, and has brought social and economic problems to many crab-harvesting communities that depend on this natural resource. The present work examined the perceptions of members of a Brazilian crab harvesting community concerning environmental changes and the Lethargic Crab Disease. Methods Field work was undertaken during the period between January and April/2009, with weekly or biweekly field excursions during which open and semi-structured interviews were held with local residents in the municipality of Mucuri, Bahia State, Brazil. A total of 23 individuals were interviewed, all of whom had at least 20 years of crab-collecting experience in the study region. Key-informants (more experienced crab harvesters were selected among the interviewees using the "native specialist" criterion. Results According to the collectors, LCD reached the Mucuri mangroves between 2004 and 2005, decimating almost all crab population in the area, and in 2007, 2008 and 2009 high mortalities of U. cordatus were again observed as a result of recurrences of this disease in the region. In addition to LCD, crabs were also suffering great stock reductions due to habitat degradation caused by deforestation, landfills, sewage effluents, domestic and industrial wastes and the introduction of exotic fish in the Mucuri River estuary. The harvesting community was found to have significant ecological knowledge about the functioning of mangrove swamp ecology, the biology of crabs, and the mass mortality that directly affected the economy of this community, and this information was largely in accordance with scientific knowledge. Conclusions The study of traditional knowledge makes it possible to better understand human interactions with the environment and aids in the elaboration of appropriate strategies for natural

Perceptions of environmental changes and lethargic crab disease among crab harvesters in a Brazilian coastal community.

Science.gov (United States)

Firmo, Angélica M S; Tognella, Mônica M P; Có, Walter L O; Barboza, Raynner R D; Alves, Rômulo R N

2011-11-16

Lethargic Crab Disease (LCD) has caused significant mortalities in the population of Ucides cordatus crabs in the Mucuri estuary in Bahia State, Brazil, and has brought social and economic problems to many crab-harvesting communities that depend on this natural resource. The present work examined the perceptions of members of a Brazilian crab harvesting community concerning environmental changes and the Lethargic Crab Disease. Field work was undertaken during the period between January and April/2009, with weekly or biweekly field excursions during which open and semi-structured interviews were held with local residents in the municipality of Mucuri, Bahia State, Brazil. A total of 23 individuals were interviewed, all of whom had at least 20 years of crab-collecting experience in the study region. Key-informants (more experienced crab harvesters) were selected among the interviewees using the "native specialist" criterion. According to the collectors, LCD reached the Mucuri mangroves between 2004 and 2005, decimating almost all crab population in the area, and in 2007, 2008 and 2009 high mortalities of U. cordatus were again observed as a result of recurrences of this disease in the region. In addition to LCD, crabs were also suffering great stock reductions due to habitat degradation caused by deforestation, landfills, sewage effluents, domestic and industrial wastes and the introduction of exotic fish in the Mucuri River estuary. The harvesting community was found to have significant ecological knowledge about the functioning of mangrove swamp ecology, the biology of crabs, and the mass mortality that directly affected the economy of this community, and this information was largely in accordance with scientific knowledge. The study of traditional knowledge makes it possible to better understand human interactions with the environment and aids in the elaboration of appropriate strategies for natural resource conservation.

Crab As A Coconut Oil Separating Agent

OpenAIRE

Margino, Sebastian

2017-01-01

The role of sterilized and nonsterilized crab extract on the separation of coconut oil was examined using grated coconut meat as substrate. Sterilized crab extract was prepared by suspension and centrifugation of crushed crab and then filtrated using Millipore Utter. Sterilized crab extract has proteolytic activity but not lipolytic one. It was found that the sterilized crab extract supported the growth of proteolytic microbes, isolated from fermentation process of coconut oil. Both sterilize...

Preservation of crab meat by gamma irradiation

International Nuclear Information System (INIS)

Loaharanu, P.; Prompubesara, C.; Kraisorn, K.; Noochpramool, K.

1972-01-01

Fresh crab meat from swimming crab (Portunus pelagicus, Linn.) was irradiated at doses of 0.075, 0.15 and 0.25 Mrad and held at 3 0 C. The storage life of non-irradiated crab meat was approximately 7 days compared with 14 days for crab meat irradiated at 0.075 Mrad and 28 days for samples receiving 0.15 or 0.25 Mrad treatment. Total aerobic count, trimethylamine nitrogen, total volatile basic nitrogen, and ammonia contents were used as objective indices of freshness in comparison with sensory evaluation of the crab meat. All objective indices correlated well with the sensory judgement of the samples. The crab meat used in the study was heavily contaminated with microorganisms. Irradiation at 0.15 and 0.25 Mrad reduced approximately 2 log cycles in the total count. Acinetobacter (Achromobacter) was predominated in irradiated crab meat, especially after prolonged storage. High coagulase positive staphylococci count was detected in only non-irradiated crab meat

AFSC/RACE/SAP/Jensen: Bitter crab disease mortality in SE Alaska Tanner crab

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — These are data from a laboratory experiment in which wild caught male Tanner crab (Chionoecetes bairdi) from Stephens Passage, SE Alaska were held to evaluate crab...

Chemical Speciation of Chromium in Drilling Muds

International Nuclear Information System (INIS)

Taguchi, Takeyoshi; Yoshii, Mitsuru; Shinoda, Kohzo

2007-01-01

Drilling muds are made of bentonite and other clays, and/or polymers, mixed with water to the desired viscosity. Without the drilling muds, corporations could not drill for oil and gas and we would have hardly any of the fuels and lubricants considered essential for modern industrial civilization. There are hundreds of drilling muds used and some kinds of drilling muds contain chromium. The chemical states of chromium in muds have been studied carefully due to concerns about the environmental influence. However it is difficult to determine the chemical state of chromium in drilling muds directly by conventional analytical methods. We have studied the chemical form of chromium in drilling muds by using a laboratory XAFS system and a synchrotron facility

Species coexistence and the superior ability of an invasive species to exploit a facilitation cascade habitat

Directory of Open Access Journals (Sweden)

Andrew H. Altieri

2017-02-01

Full Text Available Facilitation cascades generated by co-occurring foundation species can enhance the abundance and diversity of associated organisms. However, it remains poorly understood how differences among native and invasive species in their ability to exploit these positive interactions contribute to emergent patterns of community structure and biotic acceptance. On intertidal shorelines in New England, we examined the patterns of coexistence between the native mud crabs and the invasive Asian shore crab in and out of a facilitation cascade habitat generated by mid intertidal cordgrass and ribbed mussels. These crab species co-occurred in low intertidal cobbles adjacent to the cordgrass–mussel beds, despite experimental findings that the dominant mud crabs can kill and displace Asian shore crabs and thereby limit their successful recruitment to their shared habitat. A difference between the native and invasive species in their utilization of the facilitation cascade likely contributes to this pattern. Only the Asian shore crabs inhabit the cordgrass–mussel beds, despite experimental evidence that both species can similarly benefit from stress amelioration in the beds. Moreover, only Asian shore crabs settle in the beds, which function as a nursery habitat free of lethal mud crabs, and where their recruitment rates are particularly high (nearly an order of magnitude higher than outside beds. Persistence of invasive adult Asian shore crabs among the dominant native mud crabs in the low cobble zone is likely enhanced by a spillover effect of the facilitation cascade in which recruitment-limited Asian shore crabs settle in the mid intertidal cordgrass–mussel beds and subsidize their vulnerable populations in the adjacent low cobble zone. This would explain why the abundances of Asian shore crabs in cobbles are doubled when adjacent to facilitation cascade habitats. The propensity for this exotic species to utilize habitats created by facilitation cascades

Functional Assessment of Residues in the Amino- and Carboxyl-Termini of Crustacean Hyperglycemic Hormone (CHH in the Mud Crab Scylla olivacea Using Point-Mutated Peptides.

Directory of Open Access Journals (Sweden)

Chun-Jing Liu

Full Text Available To assess functional importance of the residues in the amino- and carboxyl-termini of crustacean hyperglycemic hormone in the mud crab Scylla olivacea (Sco-CHH, both wild-type and point-mutated CHH peptides were produced with an amidated C-terminal end. Spectral analyses of circular dichroism, chromatographic retention time, and mass spectrometric analysis of the recombinant peptides indicate that they were close in conformation to native CHH and were produced with the intended substitutions. The recombinant peptides were subsequently used for an in vivo hyperglycemic assay. Two mutants (R13A and I69A rSco-CHH completely lacked hyperglycemic activity, with temporal profiles similar to that of vehicle control. Temporal profiles of hyperglycemic responses elicited by 4 mutants (I2A, F3A, D12A, and D60A Sco-CHH were different from that elicited by wild-type Sco-CHH; I2A was unique in that it exhibited significantly higher hyperglycemic activity, whereas the remaining 3 mutants showed lower activity. Four mutants (D4A, Q51A, E54A, and V72A rSco-CHH elicited hyperglycemic responses with temporal profiles similar to those evoked by wild-type Sco-CHH. In contrast, the glycine-extended version of V72A rSco-CHH (V72A rSco-CHH-Gly completely lost hyperglycemic activity. By comparing our study with previous ones of ion-transport peptide (ITP and molt-inhibiting hormone (MIH using deleted or point-mutated mutants, detail discussion is made regarding functionally important residues that are shared by both CHH and ITP (members of Group I of the CHH family, and those that discriminate CHH from ITP, and Group-I from Group-II peptides. Conclusions summarized in the present study provide insights into understanding of how functional diversification occurred within a peptide family of multifunctional members.

Antarctic crabs: invasion or endurance?

Directory of Open Access Journals (Sweden)

Huw J Griffiths

Full Text Available Recent scientific interest following the "discovery" of lithodid crabs around Antarctica has centred on a hypothesis that these crabs might be poised to invade the Antarctic shelf if the recent warming trend continues, potentially decimating its native fauna. This "invasion hypothesis" suggests that decapod crabs were driven out of Antarctica 40-15 million years ago and are only now returning as "warm" enough habitats become available. The hypothesis is based on a geographically and spatially poor fossil record of a different group of crabs (Brachyura, and examination of relatively few Recent lithodid samples from the Antarctic slope. In this paper, we examine the existing lithodid fossil record and present the distribution and biogeographic patterns derived from over 16,000 records of Recent Southern Hemisphere crabs and lobsters. Globally, the lithodid fossil record consists of only two known specimens, neither of which comes from the Antarctic. Recent records show that 22 species of crabs and lobsters have been reported from the Southern Ocean, with 12 species found south of 60 °S. All are restricted to waters warmer than 0 °C, with their Antarctic distribution limited to the areas of seafloor dominated by Circumpolar Deep Water (CDW. Currently, CDW extends further and shallower onto the West Antarctic shelf than the known distribution ranges of most lithodid species examined. Geological evidence suggests that West Antarctic shelf could have been available for colonisation during the last 9,000 years. Distribution patterns, species richness, and levels of endemism all suggest that, rather than becoming extinct and recently re-invading from outside Antarctica, the lithodid crabs have likely persisted, and even radiated, on or near to Antarctic slope. We conclude there is no evidence for a modern-day "crab invasion". We recommend a repeated targeted lithodid sampling program along the West Antarctic shelf to fully test the validity of the

46 CFR 128.450 - Liquid-mud systems.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Liquid-mud systems. 128.450 Section 128.450 Shipping...: EQUIPMENT AND SYSTEMS Design Requirements for Specific Systems § 128.450 Liquid-mud systems. (a) Liquid-mud... this chapter. (b) Tanks for oil-based liquid mud must be fitted with tank vents equipped with flame...

30 CFR 250.1614 - Mud program.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Mud program. 250.1614 Section 250.1614 Mineral... OPERATIONS IN THE OUTER CONTINENTAL SHELF Sulphur Operations § 250.1614 Mud program. (a) The quantities, characteristics, use, and testing of drilling mud and the related drilling procedures shall be designed and...

Population structure of the red mangrove crab, Goniopsis cruentata (Decapoda: Grapsidae under different fishery impacts: Implications for resource management

Directory of Open Access Journals (Sweden)

Gustavo L. Hirose

2015-06-01

Full Text Available The red mangrove crab, Goniopsis cruentata, influences the recruitment and composition of plant species in the mangrove ecosystem and it is an important fishery resource. Nevertheless, no current management and conservation plans are available for this species for the Brazilian coast. This investigation evaluated the population structure and reproductive biology in populations of G. cruentata under contrasting fishery pressures. The sampling program was carried out in two mangroves, Vaza-Barris and Sergipe River, from January through December 2011. Crabs from both mangroves were randomly collected by a professional fisherman during daytime low tide periods, using a fishing rod baited with pieces of a locally abundant gastropod, Pugilina morio, during 20min/area (catch per unit effort. Monthly measurements of air, sediment surface layer and water temperatures were obtained with a digital thermometer and salinity with an optical refractometer. Both crab populations were compared concerning their abundance, body size, sex ratio, size at onset of sexual maturity and fecundity (FI. Abiotic factors (air, water and mud temperature; and salinity showed no significant differences between sampling localities. A total of 4 370 crabs were sampled, 2 829 from the Sergipe River and 1 541 from the Vaza-Barris River. The abundance and body size of crabs were compared between mangroves, and statistically significant differences were found. The sex ratio for both populations differed from the expected 1:1 ratio, and a significant deviation in favor of juvenile males was obtained, while adults showed a bias toward females. The estimated size at onset of sexual maturity for both sexes was similar in both populations. However, the populations differed significantly in the number and volume of eggs: a higher FI was obtained in females from the Sergipe River, while a higher egg volume was observed in females from the Vaza-Barris River mangrove. These results indicated

Numerical investigation of fluid mud motion using a three-dimensional hydrodynamic and two-dimensional fluid mud coupling model

Science.gov (United States)

Yang, Xiaochen; Zhang, Qinghe; Hao, Linnan

2015-03-01

A water-fluid mud coupling model is developed based on the unstructured grid finite volume coastal ocean model (FVCOM) to investigate the fluid mud motion. The hydrodynamics and sediment transport of the overlying water column are solved using the original three-dimensional ocean model. A horizontal two-dimensional fluid mud model is integrated into the FVCOM model to simulate the underlying fluid mud flow. The fluid mud interacts with the water column through the sediment flux, current, and shear stress. The friction factor between the fluid mud and the bed, which is traditionally determined empirically, is derived with the assumption that the vertical distribution of shear stress below the yield surface of fluid mud is identical to that of uniform laminar flow of Newtonian fluid in the open channel. The model is validated by experimental data and reasonable agreement is found. Compared with numerical cases with fixed friction factors, the results simulated with the derived friction factor exhibit the best agreement with the experiment, which demonstrates the necessity of the derivation of the friction factor.

Caught in the Crab's claws

CERN Multimedia

2001-01-01

'The crab', a new cryo magnet transport vehicle, starts work at CERN. Produced by the ESI group of EST division and built in Finland, it has the job of transporting LHC magnets in buildings SM18 and SMA18. If you see a huge crab scuttling around building SMA18 don't be afraid! It is the new Cryo Magnet Transport Vehicle produced by the ESI group (Engineering Support for Infrastructure, EST Division) for CERN's LHC project and built by Finnish Company ROCLA. This orange vehicle, nicknamed 'The Crab', is perhaps the strangest piece of equipment used for the construction of LHC magnets. It will start work at the end of this month. The crab will be used to transport LHC cryo-magnets and their components in the assembly and preparation building, SMA18, and test building, SM18. It has many capabilities that will allow CERN staff and contractors transport magnets between the two buildings and to locate them in the right position on the test beds. The crab in action during its first tests on 8 February. How does th...

Mud extrusion and ring-fault gas seepage - upward branching fluid discharge at a deep-sea mud volcano.

Science.gov (United States)

Loher, M; Pape, T; Marcon, Y; Römer, M; Wintersteller, P; Praeg, D; Torres, M; Sahling, H; Bohrmann, G

2018-04-19

Submarine mud volcanoes release sediments and gas-rich fluids at the seafloor via deeply-rooted plumbing systems that remain poorly understood. Here the functioning of Venere mud volcano, on the Calabrian accretionary prism in ~1,600 m water depth is investigated, based on multi-parameter hydroacoustic and visual seafloor data obtained using ship-borne methods, ROVs, and AUVs. Two seepage domains are recognized: mud breccia extrusion from a summit, and hydrocarbon venting from peripheral sites, hosting chemosynthetic ecosystems and authigenic carbonates indicative of long-term seepage. Pore fluids in freshly extruded mud breccia (up to 13 °C warmer than background sediments) contained methane concentrations exceeding saturation by 2.7 times and chloride concentrations up to five times lower than ambient seawater. Gas analyses indicate an underlying thermogenic hydrocarbon source with potential admixture of microbial methane during migration along ring faults to the peripheral sites. The gas and pore water analyses point to fluids sourced deep (>3 km) below Venere mud volcano. An upward-branching plumbing system is proposed to account for co-existing mud breccia extrusion and gas seepage via multiple surface vents that influence the distribution of seafloor ecosystems. This model of mud volcanism implies that methane-rich fluids may be released during prolonged phases of moderate activity.

Mud volcanism of South-Caspian depression

International Nuclear Information System (INIS)

Aliyev, A.A.

2002-01-01

Full text : South-Caspian depression is presented by area of large warping with thick (more than 25 km) sedimentary series and with wide development of mud volcanism. This depression is unique according to its number of mud volcanoes and intensity of their eruptions. There are about 400 mud volcanoes in this area, which is more than than a half of all volcanoes of the planet. Among them - 220 are continental, more 170 are marine, defined by different methods in the South-Caspian aquatorium. As a result of mudvolcanic activity islands, banks, shoals and underwater ridges are formed in marine conditions. Depths of underwater volcanoes vary from few meters to 900 m as the height of cones are different too. Marine mud volcanoes in geological history of Caspian sea evolution and in its recent history had and important significance. Activity of mud volcanoes in sea conditions lead to the formation of positive elements of relief. Products of ejection take part in the formation of microrelief of surrounding areas of sea bottom influence upon its dynamics and composition of bottom sediments. The carried out comparative analysis of mud volcanism manifestation both onshore and offshore showed the basic differences and similarities in morphology of volcanoes and geology-geochemical peculiarities of eruption products. New data on tectonics of mud volcanism development has been obtained over recent years. Mud volcanoes of South-Caspian depression are studied for assessment and oil-gas content of deep-seated deposits. Geochemical method of search of oil and gas deposits in mudvolcanic areas had been worked out.

Sterilizing effect of irradiation processing on drunk crab

International Nuclear Information System (INIS)

Chen Xiulan; Shen Qingkang; Bao Jianzhong; Cao Hong; Zhang Yongtai; Han Yuepeng

2001-01-01

Drunk crab is a kind of specially processed crab food with the shelf time of 3 months when stored at low temperature of l to 5℃. The shelf time of the tin paked drunk crab can be extend to 9 months when the crab food is irradiated by "6"0Co-γ rays with the dosage of 2 ∼ 8 k Gy. The irradiation processing technology will make drunk crab be supplied the whole year. (authors)

Organic chemical composition of mud from the LUSI mud volcano, Sidoarjo, East Java, Indonesia

Science.gov (United States)

Rosenbauer, R. J.; Campbell, P.; Lam, A.

2009-12-01

Sidoarjo, East Java, Indonesia is the site of LUSI, a terrestrial mud volcano that has been erupting since May 29, 2006. In response to a U.S. Department of State request, the U.S. Geological Survey has been assisting the Indonesian Government to describe the geological and geochemical aspects and potential health risk of the mud eruption. We report here on the organic chemical composition of the mud. Organic chemical analyses were carried out by gas chromatography/mass spectroscopy following organic extraction by microwave-assisted solvent extraction and compound fractionation by adsorption chromatography. There is a petroliferous component in the mud that is fresh, immature, and nonbiodegraded. There is a complete suite of n-alkanes with a bell-shaped pattern typical of fresh petroleum with a Cmax around C20. The alkane content ranges from 0.12 to 1.01 mg/kg dry mud. The presence of certain hopanes (i.e. 17 α,21β(H)-30-norhopane and 17α,21β(H)-hopane) is also indicative of the presence of oil. The proportions of other biomarker compounds (pristane/phytane = 2.4) and the dominance of the C27 sterane (5α(H),14α(H),17α(H)-chlolestane) suggest that oil formed under oxic conditions and has a likely coastal marine or terrigenous source. The presence of oleanane indicates a Cretaceous or younger age for the petrogenic material. These geochemical parameters are consistent with Indonesian oil derived from Tertiary marlstone source rocks that contained kerogen deposited under oxic conditions, probably the upper Miocene Klasafet Formation. Polycyclic aromatic hydrocarbons (PAHs) are present and range in content from 0.1 to 2.2 mg/kg dry mud. The low molecular weight (LMW) PAHs, in particular, naphthalene and methyl-naphthalene are dominant except for perylene which is ubiquitous in the environment. The presence of both parent and higher homologue PAHs indicate a petrogenic rather than combustion source. PAHs are known carcinogens but toxicity data in sediments are

Calcification–carbonation method for red mud processing

Energy Technology Data Exchange (ETDEWEB)

Li, Ruibing [School of Metallurgy, Northeastern University, Shenyang 110819 (China); Laboratory for Simulation and Modelling of Particulate Systems, Department of Chemical Engineering, Monash University, Clayton, Victoria, 3800 (Australia); Zhang, Tingan, E-mail: zhangta@smm.neu.edu.cn [School of Metallurgy, Northeastern University, Shenyang 110819 (China); Liu, Yan; Lv, Guozhi; Xie, Liqun [School of Metallurgy, Northeastern University, Shenyang 110819 (China)

2016-10-05

Highlights: • A new approach named calcification–carbonation method for red mud processing is proposed. • The method can prevent emission of red mud from alumina production and is good for the environment. • Thermodynamics characteristics were investigated. • The method was verified experimentally using a jet-flow reactor. - Abstract: Red mud, the Bayer process residue, is generated from alumina industry and causes environmental problem. In this paper, a novel calcification–carbonation method that utilized a large amount of the Bayer process residue is proposed. Using this method, the red mud was calcified with lime to transform the silicon phase into hydrogarnet, and the alkali in red mud was recovered. Then, the resulting hydrogarnet was decomposed by CO{sub 2} carbonation, affording calcium silicate, calcium carbonate, and aluminum hydroxide. Alumina was recovered using an alkaline solution at a low temperature. The effects of the new process were analyzed by thermodynamics analysis and experiments. The extraction efficiency of the alumina and soda obtained from the red mud reached 49.4% and 96.8%, respectively. The new red mud with <0.3% alkali can be used in cement production. Using a combination of this method and cement production, the Bayer process red mud can be completely utilized.

Stockpiling and Comprehensive Utilization of Red Mud Research Progress

Science.gov (United States)

Liu, Dong-Yan; Wu, Chuan-Sheng

2012-01-01

With increasing production of red mud, the environmental problems caused by it are increasingly serious, and thus the integrated treatment of red mud is imminent. This article provides an overview of the composition and the basic characteristics of red mud. The research progress of safe stockpiling and comprehensive utilization of red mud is summarized. The safe stockpiling of red mud can be divided into two aspects: the design and safe operation of the stocking yard. The comprehensive utilization of red mud can be further divided into three aspects: the effective recycling of components, resource utilization and application in the field of environmental protection. This paper points out that the main focus of previous studies on red mud stockpiling is cost reproduction and land tenure. The recovery of resources from red mud has a high value-added, but low level industrialization. The use of red mud as a building material and filler material is the most effective way to reduce the stockpiling of red mud. Red mud used for environmental remediation materials is a new hotspot and worth promoting for its simple processing and low cost.

METHODS OF IMPROVING THE MUD PUMP VALVE LIFE

Directory of Open Access Journals (Sweden)

Miruna BĂLTĂREȚU IANCU

2015-11-01

Full Text Available Petroleum drilling rigs are used for identifying geologic reservoirs and for creating wells for extraction. The mud pumps of drilling rigs are operated at high mud rates to make possible the drilling process. The durability of the mud pump valves to erosive wear, due to the action of abrasive drilling fluid containing solid particles, depends on their constructive form and on the mud flow velocity. This paper analyzes a few methods of increasing the wear resistance of mud pump valves.

Modeling of Mud-Wave Interaction: Mud-Induced Wave Transport & Wave-Induced Mud Transport

National Research Council Canada - National Science Library

Winterwerp, Johan C

2007-01-01

.... Also a new rheological model has been proposed to describe liquefaction of soft mud by waves, and the subsequent strength recovery after the passage of the waves. A scheme is presented on how to implement these formulations in Delft3D.

Profilicollis novaezelandensis n. sp. (Polymorphidae) and two other acanthocephalan parasites from shore birds (Haematopodidae and Scolopacidae) in New Zealand, with records of two species in intertidal crabs (Decapoda: Grapsidae and Ocypodidae).

Science.gov (United States)

Brockerhoff, A M; Smales, L R

2002-05-01

Profilicollis novaezelandensis n. sp. (Acanthocephala: Polymorphidae) is described from the South Island pied oystercatcher Haematopus ostralegus finschi Martens (Haematopodidae) and the intertidal crab Hemigrapsus crenulatus (Milne Edwards) (Brachyura: Grapsidae) from the South Island of New Zealand. The new species can be distinguished from all the other species of the genus by a combination of the following characters: long neck (13% of total body length for adults) and a subspherical proboscis with 14-16 longitudinal rows of 7-8 hooks. The mud crabs Helice crassa Dana (Grapsidae) and Macrophthalmus hirtipes (Heller) (Ocypodidae) were also harbouring cystacanths and the bar-tailed godwit Limosa lapponica (Linnaeus) (Scolopacidae) juveniles of P. novaezelandensis. This is the first record of brachyuran decapods as intermediate hosts of Acanthocephala from New Zealand. P. antarcticus is recorded from three crab species (Helice crassa, Hemigraspus crenulatus and Macrophthalmus hirtipes) and two bird species (Haematopus o. finschi and Limosa lapponica) in New Zealand. An unidentified species of Plagiorhynchus was also found in two bird species (H. o. finschi and H. unicolor Forster). P. antarcticus and P. novaezelandensis are the first records of Profilicollis from New Zealand.

50 CFR 680.21 - Crab harvesting cooperatives.

Science.gov (United States)

2010-10-01

... establishes an annual catch limit of crab that is based on the collective QS holdings of the members of the... the members of the crab harvesting cooperative. (2) Contents of application for annual crab harvesting... permit may appeal the IAD using the appeals procedures described in § 680.43. (c) Restrictions on fishing...

Changes of exoskeleton surface roughness and expression of crucial participation genes for chitin formation and digestion in the mud crab (Macrophthalmus japonicus) following the antifouling biocide irgarol.

Science.gov (United States)

Park, Kiyun; Nikapitiya, Chamilani; Kim, Won-Seok; Kwak, Tae-Soo; Kwak, Ihn-Sil

2016-10-01

Irgarol is a common antifoulant present in coastal sediment. The mud crab Macrophthalmus japonicus is one of the most abundant of the macrobenthos in the costal environment, and its exoskeleton has a protective function against various environmental threats. We evaluated the effects of irgarol toxicity on the exoskeleton of M. japonicus, which is the outer layer facing the environment. We analyzed transcriptional expression of exoskeleton, molting, and proteolysis-related genes in the gill and hepatopancreas of these exposed M. japonicus. In addition, changes in survival and exoskeleton surface characteristics were investigated. In the hepatopancreas, mRNA expression of chitinase 1 (Mj-chi1), chitinase 4 (Mj-chi4), and chitinase 5 (Mj-chi5) increased in M. japonicus exposed to all concentrations of irgarol. Mj-chi1 and Mj-chi4 expressions from 1 to 10μgL(-1) were dose- and time-dependent. Ecdysteroid receptor (Mj-EcR), trypsin (Mj-Tryp), and serine proteinase (Mj-SP) in the hepatopancreas were upregulated in response to different exposure levels of irgarol at day 1, 4, or 7. In contrast, gill Mj-chi5, Mj-Tryp, and Mj-SP exhibited late upregulated responses to 10μgL(-1) irgarol compared to the control at day 7. Mj-chi1 showed early upregulation upon exposure to 10μgL(-1) irgarol and Mj-chi4 showed no changes in transcription in the gill. Gill Mj-EcR presented generally downregulated expression patterns. In addition, decreased survival and change of exoskeleton surface roughness were observed in M. japonicus exposed to the three concentrations of irgarol. These results suggest that exposure to irgarol induces changes in the exoskeleton, molting, and proteolysis metabolism of M. japonicus. Copyright © 2016 Elsevier Inc. All rights reserved.

Bulk additive system reduces mud costs and waste

International Nuclear Information System (INIS)

Wisnie, A.P.

1994-01-01

Today, personnel safety and environmental acceptability are high priorities in oil and gas operations. Many advances have been made, but packaging and handling of drilling mud has not changed in 35 years. In most cases, bulk barite is available, however, drilling muds are typically built from chemicals contained in 50 to 100-lb sacks or 5-gal buckets. Materials must be physically opened by rig personnel and mixed into drilling mud. Chemical exposure liability, and lifting or housekeeping related injuries associated with large quantities of packaging pose serious occupational safety risk. Figures from OSHA (1986) indicate that of 1,492 serious injury cases in Louisiana oil and gas operations, 42% were to back and lower extremities, 3% were eye injuries and 1% were chemical burns. Although exact figures are not available, experience suggests that a significant number of injuries are related to mud product physical handling. Another problem with current mud packaging is generated waste. Mud material lost because of broken sacks, inefficient transfer and as residue is unacceptable. Most mud engineers agree that 5 to 15% of mud products are lost or damaged on typical offshore jobs, depending on weather. When material that is spilled or left in packages, probably 2 to 3%, is added, the total is significant. Reusable containers for drilling mud products and manifold system design effectively eliminate these problems

Monitoring the Crab Nebula with LOFT

Science.gov (United States)

Wilson-Hodge, Colleen A.

2012-01-01

From 2008-2010, the Crab Nebula was found to decline by 7% in the 15-50 keV band, consistently in Fermi GBM, INTEGRAL IBIS, SPI, and JEMX, RXTE PCA, and Swift BAT. From 2001-2010, the 15-50 keV flux from the Crab Nebula typically varied by about 3.5% per year. Analysis of RXTE PCA data suggests possible spectral variations correlated with the flux variations. I will present estimates of the LOFT sensitivity to these variations. Prior to 2001 and since 2010, the observed flux variations have been much smaller. Monitoring the Crab with the LOFT WFM and LAD will provide precise measurements of flux variations in the Crab Nebula if it undergoes a similarly active episode.

Utilization of red mud and Pb/Zn smelter waste for the synthesis of a red mud-based cementitious material.

Science.gov (United States)

Li, Yuan-Cheng; Min, Xiao-Bo; Ke, Yong; Chai, Li-Yuan; Shi, Mei-Qing; Tang, Chong-Jian; Wang, Qing-Wei; Liang, Yan-Jie; Lei, Jie; Liu, De-Gang

2018-02-15

A new method in which Pb/Zn smelter waste containing arsenic and heavy metals (arsenic sludge), red mud and lime are utilized to prepare red mud-based cementitious material (RCM) is proposed in this study. XRD, SEM, FTIR and unconfined compressive strength (UCS) tests were employed to assess the physicochemical properties of RCM. In addition, ettringite and iron oxide-containing ettringite were used to study the hydration mechanism of RCM. The results show that the UCS of the RCM (red mud+arsenic sludge+lime) was higher than that of the binder (red mud+arsenic sludge). When the mass ratio of m (binder): m (lime) was 94:6 and then maintained 28days at ambient temperature, the UCS reached 12.05MPa. The red mud has potential cementitious characteristics, and the major source of those characteristics was the aluminium oxide. In the red mud-arsenic sludge-lime system, aluminium oxide was effectively activated by lime and gypsum to form complex hydration products. Some of the aluminium in ettringite was replaced by iron to form calcium sulfoferrite hydrate. The BCR and leaching toxicity results show that the leaching concentration was strongly dependent on the chemical speciation of arsenic and the hydration products. Therefore, the investigated red mud and arsenic sludge can be successfully utilized in cement composites to create a red mud-based cementitious material. Copyright © 2017 Elsevier B.V. All rights reserved.

Gulf of Mexico mud toxicity limitations

Energy Technology Data Exchange (ETDEWEB)

Dunn, H.E.; Beardmore, D.H. (Phillips Petroleum Co., Bartlesville, OK (USA)); Stewart, W.S. (Drilling Specialties Co. (US))

1989-10-01

Because of the Environmental Protection Agency's recent toxicity limits on drilling mud discharges for offshore Gulf of Mexico, Phillips Petroleum conducted a mud toxicity study based on both field and lab tests. The study, discussed in this article, found the polyanionic cellulose-sulfomethylated quebracho-chrome lignosulfonate mud Phillips had been using would comfortably pass the toxicity limitations. The study also found barite and thinners were of low toxicity, and hydrocarbons and surfactants were highly toxic.

Predatory blue crabs induce stronger nonconsumptive effects in eastern oysters Crassostrea virginica than scavenging blue crabs

Directory of Open Access Journals (Sweden)

Avery E. Scherer

2017-02-01

Full Text Available By influencing critical prey traits such as foraging or habitat selection, predators can affect entire ecosystems, but the nature of cues that trigger prey reactions to predators are not well understood. Predators may scavenge to supplement their energetic needs and scavenging frequency may vary among individuals within a species due to preferences and prey availability. Yet prey reactions to consumers that are primarily scavengers versus those that are active foragers have not been investigated, even though variation in prey reactions to scavengers or predators might influence cascading nonconsumptive effects in food webs. Oysters Crassostrea virginica react to crab predators by growing stronger shells. We exposed oysters to exudates from crabs fed live oysters or fed aged oyster tissue to simulate scavenging, and to controls without crab cues. Oysters grew stronger shells when exposed to either crab exudate, but their shells were significantly stronger when crabs were fed live oysters. The stronger response to predators than scavengers could be due to inherent differences in diet cues representative of reduced risk in the presence of scavengers or to degradation of conspecific alarm cues in aged treatments, which may mask risk from potential predators subsisting by scavenging.

The Porcelain Crab Transcriptome and PCAD, the Porcelain Crab Microarray and Sequence Database

Energy Technology Data Exchange (ETDEWEB)

Tagmount, Abderrahmane; Wang, Mei; Lindquist, Erika; Tanaka, Yoshihiro; Teranishi, Kristen S.; Sunagawa, Shinichi; Wong, Mike; Stillman, Jonathon H.

2010-01-27

Background: With the emergence of a completed genome sequence of the freshwater crustacean Daphnia pulex, construction of genomic-scale sequence databases for additional crustacean sequences are important for comparative genomics and annotation. Porcelain crabs, genus Petrolisthes, have been powerful crustacean models for environmental and evolutionary physiology with respect to thermal adaptation and understanding responses of marine organisms to climate change. Here, we present a large-scale EST sequencing and cDNA microarray database project for the porcelain crab Petrolisthes cinctipes. Methodology/Principal Findings: A set of ~;;30K unique sequences (UniSeqs) representing ~;;19K clusters were generated from ~;;98K high quality ESTs from a set of tissue specific non-normalized and mixed-tissue normalized cDNA libraries from the porcelain crab Petrolisthes cinctipes. Homology for each UniSeq was assessed using BLAST, InterProScan, GO and KEGG database searches. Approximately 66percent of the UniSeqs had homology in at least one of the databases. All EST and UniSeq sequences along with annotation results and coordinated cDNA microarray datasets have been made publicly accessible at the Porcelain Crab Array Database (PCAD), a feature-enriched version of the Stanford and Longhorn Array Databases.Conclusions/Significance: The EST project presented here represents the third largest sequencing effort for any crustacean, and the largest effort for any crab species. Our assembly and clustering results suggest that our porcelain crab EST data set is equally diverse to the much larger EST set generated in the Daphnia pulex genome sequencing project, and thus will be an important resource to the Daphnia research community. Our homology results support the pancrustacea hypothesis and suggest that Malacostraca may be ancestral to Branchiopoda and Hexapoda. Our results also suggest that our cDNA microarrays cover as much of the transcriptome as can reasonably be captured in

Pubic "Crab" Lice Prevention and Control

Science.gov (United States)

... and General Public. Contact Us Parasites Home Prevention & Control Recommend on Facebook Tweet Share Compartir Pubic ("crab") ... that can be taken to help prevent and control the spread of pubic ("crab") lice: All sexual ...

Mud dynamics on the shoreface and upper shelf, Noordwijk, The Netherlands

NARCIS (Netherlands)

Kleinhans, M.G.; Montfort, O.; Dankers, P.J.T.; Rijn, L.C. van; Bonne, W.

2005-01-01

Mud dynamics on the shoreface were studied with measured mud concentrations in the water related to hydrodynamics and measured mud concentrations in the sandy bed. In addition, mud infiltration into the bed was modelled and mud inmixing into the bed by macro-benthos was assessed. The mud

Clay mineralogy of the mud banks of Cochin

Digital Repository Service at National Institute of Oceanography (India)

Nair, R.R.; Murty, P.S.N.

The mineralogy of the sediments constituting the mud banks formed off Cochin, Kerala, India was studied. The clay mineral composition was used as a means of understanding the nature and source of origin of the muds. Fine fraction of the mud samples...

Mud volcanos and mud domes of the central Mediterranean Ridge: near bottom and in situ observations

NARCIS (Netherlands)

Huguen, C.; Mascle, J.; Woodside, J.M.; Zitter, T.A.C.; Foucher, J.-P.

2005-01-01

The first high-resolution mapping of mud volcanoes and mud domes of the Central Mediterranean Ridge (Eastern Mediterranean) presented here is based on successive in situ observations from the Nautile submersible [MEDINAUT (1998) and NAUTINIL (2003) surveys] and near-bottom side-scan sonar data

Hyperspectral remote sensing and mud volcanism in Azerbaijan

NARCIS (Netherlands)

Scholte, K.H.

2005-01-01

The fact that Azerbaijan mud volcanoes are closely associated with oil and gas makes their study and identification of the physical and chemical properties of insitu mud volcano surfaces important. Although the composition of in-situ mud volcano surfaces can be highly variable, it usually

WAKEFIELD DAMPING FOR THE CLIC CRAB CAVITY

CERN Document Server

Ambattu, P; Dexter, A; Carter, R; Khan, V; Jones, R; Dolgashev, V

2009-01-01

A crab cavity is required in the CLIC to allow effective head-on collision of bunches at the IP. A high operating frequency is preferred as the deflection voltage required for a given rotation angle and the RF phase tolerance for a crab cavity are inversely proportional to the operating frequency. The short bunch spacing of the CLIC scheme and the high sensitivity of the crab cavity to dipole kicks demand very high damping of the inter-bunch wakes, the major contributor to the luminosity loss of colliding bunches. This paper investigates the nature of the wakefields in the CLIC crab cavity and the possibility of using various damping schemes to suppress them effectively.

Potential Impact of Submarine Power Cables on Crab Harvest

Science.gov (United States)

Bull, A. S.; Nishimoto, M.

2016-02-01

Offshore renewable energy installations convert wave or wind energy to electricity and transfer the power to shore through transmission cables laid on or buried beneath the seafloor. West coast commercial fishermen, who harvest the highly prized Dungeness crab (Metacarcinus magister) and the rock crab (Cancer spp.), are concerned that the interface of crabs and electromagnetic fields (EMF) from these cables will present an electrified fence on the seafloor that their target resource will not cross. Combined with the assistance of professional fishermen, submarine transmission cables that electrify island communities and offshore oil platforms in the eastern Pacific provide an opportunity to test the harvest of crab species across power transmission cables. In situ field techniques give commercial crab species a choice to decide if they will cross fully energized, EMF emitting, power transmission cables, in response to baited traps. Each independent trial is either one of two possible responses: the crab crosses the cable to enter a trap (1) or the crab does not cross the cable to enter a trap (0). Conditions vary among sample units by the following categorical, fixed factors (i.e., covariates) of cable structure (buried or unburied); direction of cable from crab position (west or east, north or south); time and season. A generalized linear model is fit to the data to determine whether any of these factors affect the probability of crabs crossing an energized cable to enter baited traps. Additionally, the experimental design, aside from the number of runs (set of sample trials) and the dates of the runs, is the same in the Santa Barbara Channel for rock crab and Puget Sound for Dungeness crab, and allows us to compare the capture rates of the two species in the two areas. We present preliminary results from field testing in 2015.

Cyclic Activity of Mud Volcanoes: Evidences from Trinidad (SE Caribbean)

Science.gov (United States)

Deville, E.

2007-12-01

Fluid and solid transfer in mud volcanoes show different phases of activity, including catastrophic events followed by periods of relative quiescence characterized by moderate activity. This can be notably shown by historical data onshore Trinidad. Several authors have evoked a possible link between the frequencies of eruption of some mud volcanoes and seismic activity, but in Trinidad there is no direct correlation between mud eruptions and seisms. It appears that each eruptive mud volcano has its own period of catastrophic activity, and this period is highly variable from one volcano to another. The frequency of activity of mud volcanoes seems essentially controlled by local pressure regime within the sedimentary pile. At the most, a seism can, in some cases, activate an eruption close to its term. The dynamics of expulsion of the mud volcanoes during the quiescence phases has been studied notably from temperature measurements within the mud conduits. The mud temperature is concurrently controlled by, either, the gas flux (endothermic gas depressurizing induces a cooling effect), or by the mud flux (mud is a vector for convective heat transfer). Complex temperature distribution was observed in large conduits and pools. Indeed, especially in the bigger pools, the temperature distribution characterizes convective cells with an upward displacement of mud above the deep outlet, and ring-shaped rolls associated with the burial of the mud on the flanks of the pools. In simple, tube-like shaped, narrow conduits, the temperature is more regular, but we observed different types of profiles, with either downward increasing or decreasing temperatures. If the upward flow of mud would be regular, we should expect increasing temperatures and progressively decreasing gradient with depth within the conduits. However, the variable measured profiles from one place to another, as well as time-variable measured temperatures within the conduits and especially, at the base of the

Structural and functional comparisons and production of recombinant crustacean hyperglycemic hormone (CHH) and CHH-like peptides from the mud crab Scylla olivacea.

Science.gov (United States)

Chang, Chih-Chun; Tsai, Kuo-Wei; Hsiao, Nai-Wan; Chang, Cheng-Yen; Lin, Chih-Lung; Watson, R Douglas; Lee, Chi-Ying

2010-05-15

Sco-CHH and Sco-CHH-L (CHH-like peptide), two structural variants of the crustacean hyperglycemic hormone family identified in the mud crab (Scylla olivacea), are presumably alternatively spliced gene products. In this study, Sco-CHH and Sco-CHH-L were isolated from the tissues using high performance liquid chromatography. Identity of the native peptides was confirmed using mass spectrometric (MS) analyses of purified materials and of trypsin-digested peptide fragments. Additionally, characterizations using circular dichroism (CD) spectrometry revealed that the 2 peptides have similar CD spectral profiles, showing they are composed mainly of alpha-helices, and are similarly thermo-stable with a melting temperature of 74-75 degrees C. Results of bioassays indicated that Sco-CHH exerted hyperglycemic and molt-inhibiting activity, whereas Sco-CHH-L did not. Further, recombinant Sco-CHH-Gly (rSco-CHH-Gly, a glycine extended Sco-CHH) and Sco-CHH-L (rSco-CHH-L) were produced using an Escherichia coli expression system, refolded, and purified. rSco-CHH-Gly was further alpha-amidated at the C-terminal end to produce rSco-CHH. MS analyses of enzyme-digested peptide fragments of rSco-CHH-Gly and rSco-CHH-L showed that the two peptides share a common disulfide bond pattern: C7-C43, C23-C39, and C26-C52. Circular dichroism analyses and hyperglycemic assay revealed that rSco-CHH and rSco-CHH-L resemble their native counterparts, in terms of CD spectral profiles, melting curve profiles, and biological activity. rSco-CHH-Gly has a lower alpha-helical content (32%) than rSco-CHH (47%), a structural deviation that may be responsible for the significant decrease in the biological activity of rSco-CHH-Gly. Finally, modeled structure of Sco-CHH and Sco-CHH-L indicated that they are similarly folded, each with an N-terminal tail region and 4 alpha-helices. Putative surface residues located in corresponding positions of Sco-CHH and Sco-CHH-L but with side chains of different properties

Chemical monitoring of mud products on drilled cuttings

International Nuclear Information System (INIS)

Hughes, T.L.; Jones, T.G.J.; Tomkins, P.G.; Gilmour, A.; Houwen, O.H.; Sanders, M.

1991-01-01

An increasing area of concern for offshore drilling practices in the environmental impact of discharged drilled cuttings contaminated with drilling fluids. The standard retort analysis is of limited accuracy and chemical specificity. Anticipating future requirements for a more complete accounting of mud chemicals discharged to the environment, we present here results for chemical monitoring using a modern comprehensive chemical analysis technique. Fourier transform infrared (FT-IR) spectrometry. In this paper description is given of sampling methods found to be practical and the main calibration requirements are discussed. The techniques developed in the course of this work give a good mineralogical breakdown of mud solids (commercial and drilled solids) in addition to the environmentally relevant measurements relating to mud on cuttings. The possibility of using the new technique for the rigsite monitoring of drilling cuttings is demonstrated. Cuttings samples simultaneously from the flow line, shaker screen, desilter and mud cleaner were analyzed. It is found that mud polymers and other organic additives can be measured with sufficient accuracy to measure the removal of mud products by discharged cuttings. The technique is also applicable to quantify the losses of oil-based mud on cuttings. Field testing has shown that the instrumentation used in sufficiently robust and simple to use for rig-site application

Mud Flow Characteristics Occurred in Izuoshima Island, 2013

Science.gov (United States)

Takebayashi, H.; Egashira, S.; Fujita, M.

2015-12-01

Landslides and mud flows were occurred in the west part of the Izuoshima Island, Japan on 16 October 2013. The Izuoshima Island is a volcanic island and the land surface is covered by the volcanic ash sediment in 1m depth. Hence, the mud flow with high sediment concentration was formed. The laminar layer is formed in the debris flow from the bed to the fluid surface. On the other hand, the laminar flow is restricted near the bed in the mud flow and the turbulence flow is formed on the laminar flow layer. As a result, the equilibrium slope of the mud flow becomes smaller comparing to the debris flow. In this study, the numerical analysis mud flow model considering the effect of turbulence flow on the equilibrium slope of the mud flow is developed. Subsequently, the model is applied to the mud flow occurred in the Izuoshima Island and discussed the applicability of the model and the flow characteristics of the mud flow. The differences of the horizontal flow areas between the simulated results and the field data are compared and it was found that the outline of the horizontal shape of the flow areas is reproduced well. Furthermore, the horizontal distribution of the erosion and deposition area is reproduced by the numerical analysis well except for the residential area (Kandachi area). Kandachi area is judged as the erosion area by the field observation, but the sediment was deposited in the numerical analysis. It is considered that the 1.5hour heavy rain over 100mm/h after the mud flow makes the discrepancy. The difference of the horizontal distribution of the maximum flow surface elevation between the simulated results and the field data are compared and it was found that the simulated flow depth is overestimated slightly, because of the wider erosion area due to the coarse resolution elevation data. The averaged velocity and the depth of the mud flow was enough large to collapse the houses.

Mud Flow - Slow and Fast

Science.gov (United States)

Mei, C. C.; Liu, K.-F.; Yuhi, M.

Heavy and persistent rainfalls in mountainous areas can loosen the hillslope and induce mud flows which can move stones, boulders and even trees, with destructive power on their path. In China where 70% of the land surface is covered by mountains, debris flows due to landslides or rainfalls affect over 18.6% of the nation. Over 10,000 debris flow ravines have been identified; hundreds of lives are lost every year [1]. While accurate assessment is still pending, mud flows caused by Hurr icane Mitch in 1998 have incurred devastating floods in Central America. In Honduras alone more than 6000 people perished. Half of the nation's infrastructures were damaged. Mud flows can also be the result of volcanic eruption. Near the volcano, lava and pyroclastic flows dominate. Further downstream solid particles become smaller and can mix with river or lake water, rainfall, melting snow or ice, or eroded soil, resulting in hyperconcentrated mud mixed with rocks. The muddy debris can travel at high speeds over tens of miles down the hill slopes and devastate entire communities. In 1985 the catastrophic eruption of Nevado del Ruiz in Colombia resulted in mud flows which took the life of 23,000 inhabitants in the town of Amero [2]. During the eruption of Mt. Pinatubo in Phillipnes in 1991, one cubic mile of volcanic ash and rock fragments fell on the mountain slopes. Seasonal rain in the following months washed down much of the loose deposits, causing damage to 100,000 villages. These catastrophes have been vividly recorded in the film documentary by Lyons [3].

Hidden values in bauxite residue (red mud): Recovery of metals

Energy Technology Data Exchange (ETDEWEB)

Liu, Yanju; Naidu, Ravi, E-mail: ravi.naidu@unisa.edu.au

2014-12-15

Highlights: • Current iron recovery techniques using red mud are depicted. • Advantages and disadvantages exist in different recovering processes. • Economic and environmental friendly integrated usage of red mud is promising. - Abstract: Bauxite residue (red mud) is a hazardous waste generated from alumina refining industries. Unless managed properly, red mud poses significant risks to the local environment due to its extreme alkalinity and its potential impacts on surface and ground water quality. The ever-increasing generation of red mud poses significant challenges to the aluminium industries from management perspectives given the low proportion that are currently being utilized beneficially. Red mud, in most cases, contains elevated concentrations of iron in addition to aluminium, titanium, sodium and valuable rare earth elements. Given the scarcity of iron supply globally, the iron content of red mud has attracted increasing research interest. This paper presents a critical overview of the current techniques employed for iron recovery from red mud. Information on the recovery of other valuable metals is also reviewed to provide an insight into the full potential usage of red mud as an economic resource rather than a waste. Traditional hydrometallurgy and pyrometallurgy are being investigated continuously. However, in this review several new techniques are introduced that consider the process of iron recovery from red mud. An integrated process which can achieve multiple additional values from red mud is much preferred over the single process methods. The information provided here should help to improve the future management and utilization of red mud.

Hidden values in bauxite residue (red mud): Recovery of metals

International Nuclear Information System (INIS)

Liu, Yanju; Naidu, Ravi

2014-01-01

Highlights: • Current iron recovery techniques using red mud are depicted. • Advantages and disadvantages exist in different recovering processes. • Economic and environmental friendly integrated usage of red mud is promising. - Abstract: Bauxite residue (red mud) is a hazardous waste generated from alumina refining industries. Unless managed properly, red mud poses significant risks to the local environment due to its extreme alkalinity and its potential impacts on surface and ground water quality. The ever-increasing generation of red mud poses significant challenges to the aluminium industries from management perspectives given the low proportion that are currently being utilized beneficially. Red mud, in most cases, contains elevated concentrations of iron in addition to aluminium, titanium, sodium and valuable rare earth elements. Given the scarcity of iron supply globally, the iron content of red mud has attracted increasing research interest. This paper presents a critical overview of the current techniques employed for iron recovery from red mud. Information on the recovery of other valuable metals is also reviewed to provide an insight into the full potential usage of red mud as an economic resource rather than a waste. Traditional hydrometallurgy and pyrometallurgy are being investigated continuously. However, in this review several new techniques are introduced that consider the process of iron recovery from red mud. An integrated process which can achieve multiple additional values from red mud is much preferred over the single process methods. The information provided here should help to improve the future management and utilization of red mud

Effect of Mudflat Trampling on Activity of Intertidal Crabs

Science.gov (United States)

Kim, Tae Won; Kim, Sanha; Lee, Jung-Ah

2018-03-01

Many people visit intertidal mudflats to collect bait and seafood, or for eco-tourism and recreation, and as a consequence trample on the mudflats frequently. Trampling would not be life threatening to most animals in the intertidal flats as they have evolved hiding behavior to escape predation. However, what is the effect of trampling on the behavior of intertidal animals? In this study, the effect of mudflat trampling on the activity of crabs (e.g. fiddler crabs, sentinel crabs) living on the mudflat was explored. The number of crabs active on the mudflat surface in experimental plots (1.5 × 1.5 m2) before and after (10 min. and 30 min.) trampling of three different intensities (Heavy trampling = 60 steps; Moderate trampling = 20 steps; and No trampling) was compared in two different mudflat systems. After trampling, the number of crabs active on the surface decreased and was significantly lower than that of control plots. The more intensively trampled the mudflat was, the fewer crabs were active on the mudflat surface. Surprisingly, the number of active crabs did not recover even 30 min. after trampling. The results clearly support the hypothesis that trampling can severely interfere with the behavior of crabs living on intertidal mudflats.

The Crab Boat Engineering Design Challenge

Science.gov (United States)

Love, Tyler S.; Ryan, Larry

2017-01-01

Crab cakes and football, that's what Maryland does!" (Abrams, Levy, Panay, & Dobkin, 2005). Although the Old Line State is notorious for harvesting delectable blue crabs, the movie "Wedding Crashers" failed to highlight something else Maryland does well: engineering design competitions. This article discusses how a multistate…

Monitoring drilling mud composition using flowing liquid junction electrodes

Energy Technology Data Exchange (ETDEWEB)

Jasinski, R; Fletcher, P; Vercaemer, C

1990-06-27

The concentration of a chosen ionic component of a drilling mud is determined from the potential difference between an ion selective electrode, selective to the component and a reference electrode, the reference electrode being connected to the mud by a liquid junction through which reference electrolyte flows from the electrode to the mud. The system avoids errors due to undesirable interactions between the mud and the reference electrode materials. (author).

Turbidity interferes with foraging success of visual but not chemosensory predators.

Science.gov (United States)

Lunt, Jessica; Smee, Delbert L

2015-01-01

Predation can significantly affect prey populations and communities, but predator effects can be attenuated when abiotic conditions interfere with foraging activities. In estuarine communities, turbidity can affect species richness and abundance and is changing in many areas because of coastal development. Many fish species are less efficient foragers in turbid waters, and previous research revealed that in elevated turbidity, fish are less abundant whereas crabs and shrimp are more abundant. We hypothesized that turbidity altered predatory interactions in estuaries by interfering with visually-foraging predators and prey but not with organisms relying on chemoreception. We measured the effects of turbidity on the predation rates of two model predators: a visual predator (pinfish, Lagodon rhomboides) and a chemosensory predator (blue crabs, Callinectes sapidus) in clear and turbid water (0 and ∼100 nephelometric turbidity units). Feeding assays were conducted with two prey items, mud crabs (Panopeus spp.) that rely heavily on chemoreception to detect predators, and brown shrimp (Farfantepenaus aztecus) that use both chemical and visual cues for predator detection. Because turbidity reduced pinfish foraging on both mud crabs and shrimp, the changes in predation rates are likely driven by turbidity attenuating fish foraging ability and not by affecting prey vulnerability to fish consumers. Blue crab foraging was unaffected by turbidity, and blue crabs were able to successfully consume nearly all mud crab and shrimp prey. Turbidity can influence predator-prey interactions by reducing the feeding efficiency of visual predators, providing a competitive advantage to chemosensory predators, and altering top-down control in food webs.

Effects of ocean acidification on juvenile red king crab (Paralithodes camtschaticus and Tanner crab (Chionoecetes bairdi growth, condition, calcification, and survival.

Directory of Open Access Journals (Sweden)

William Christopher Long

Full Text Available Ocean acidification, a decrease in the pH in marine waters associated with rising atmospheric CO2 levels, is a serious threat to marine ecosystems. In this paper, we determine the effects of long-term exposure to near-future levels of ocean acidification on the growth, condition, calcification, and survival of juvenile red king crabs, Paralithodes camtschaticus, and Tanner crabs, Chionoecetes bairdi. Juveniles were reared in individual containers for nearly 200 days in flowing control (pH 8.0, pH 7.8, and pH 7.5 seawater at ambient temperatures (range 4.4-11.9 °C. In both species, survival decreased with pH, with 100% mortality of red king crabs occurring after 95 days in pH 7.5 water. Though the morphology of neither species was affected by acidification, both species grew slower in acidified water. At the end of the experiment, calcium concentration was measured in each crab and the dry mass and condition index of each crab were determined. Ocean acidification did not affect the calcium content of red king crab but did decrease the condition index, while it had the opposite effect on Tanner crabs, decreasing calcium content but leaving the condition index unchanged. This suggests that red king crab may be able to maintain calcification rates, but at a high energetic cost. The decrease in survival and growth of each species is likely to have a serious negative effect on their populations in the absence of evolutionary adaptation or acclimatization over the coming decades.

33 CFR 117.177 - Mud Slough.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mud Slough. 117.177 Section 117.177 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements California § 117.177 Mud Slough. The draw of the Union Pacific...

Are vent crab behavioral preferences adaptations for habitat choice?

Science.gov (United States)

Dahms, Hans-Uwe; Tseng, Li-Chun; Hwang, Jiang-Shiou

2017-01-01

Hydrothermal vent organisms are adapted to their extreme and patchily distributed habitats. They are expected to have evolved mechanisms that keep them in their specific habitation. Since little is known about the recruitment or habitat selection of HV organisms such as brachyurans, we examined the properties of several hydrothermal vent-associated cues on the behavior of the hydrothermal vent (HV) crab Xenograpsus testudinatus in the laboratory that were contrasted by the offering of non-vent cues. This crab species is endemic and dominates the vent fauna of Turtle Island off the NE coast of Taiwan. HV crabs were separately and in combination offered the following vent-specific cues: (1) sulfuric sediment, (3) air-bubbling, (4) elevated temperature, (5) dead settled zooplankton, (7) other crabs, and (8) shade. The non-vent-specific cues were: (2) quarz sediment, (6) dead fish, (8) light. These cues were provided on either side of a two-choice chamber. The movement of individual crabs was monitored: as initial and final choices, and as the proportion of time the crabs spent in each compartment (resident time). Cues were offered alone and no such cue as a control in the same set-up. Sulfuric sediments and dead fish were significantly more attractive to females, and other crabs irrespective of gender were significantly more attractive to males. When compared to expected distributions, crabs, irrespective of gender, significantly avoided light and tended to select other crabs, air-bubbling, sulfuric sediment, elevated temperature, dead fish, dead zooplankton, and quarz sediments in the order of decreasing importance. Data do not support the hypothesis that dead settled zooplankton was particularly attractive nor that the other gender was selected. A combination of several vent-associated cues (sulfuric sediment, elevated temperature, air-bubbling) facilitated the strongest attraction to the crabs as reflected by all response variables. The 'first choice' responses

50 CFR Table 7 to Part 680 - Initial Issuance of Crab QS by Crab QS Fishery

Science.gov (United States)

2010-10-01

... June 10, 2002 in the Eastern Aleutian Island golden (brown) king crab, Western Aleutian Island golden... through February 8, 2002. 4 years 3. Eastern Aleutian Islands golden king crab (EAG) 5 years of the 5-year... through September 24, 2000. (3) August 15, 2001 through September 10, 2001. 5 years 4. Eastern Bering Sea...

AudioMUD: a multiuser virtual environment for blind people.

Science.gov (United States)

Sánchez, Jaime; Hassler, Tiago

2007-03-01

A number of virtual environments have been developed during the last years. Among them there are some applications for blind people based on different type of audio, from simple sounds to 3-D audio. In this study, we pursued a different approach. We designed AudioMUD by using spoken text to describe the environment, navigation, and interaction. We have also introduced some collaborative features into the interaction between blind users. The core of a multiuser MUD game is a networked textual virtual environment. We developed AudioMUD by adding some collaborative features to the basic idea of a MUD and placed a simulated virtual environment inside the human body. This paper presents the design and usability evaluation of AudioMUD. Blind learners were motivated when interacted with AudioMUD and helped to improve the interaction through audio and interface design elements.

Super-Acceleration in the Flaring Crab Nebula

Energy Technology Data Exchange (ETDEWEB)

Tavani, Marco, E-mail: marco.tavani@inaf.it

2013-10-15

The Crab Nebula continues to surprise us. The Crab system (energized by a very powerful pulsar at the center of the Supernova Remnant SN1054) is known to be a very efficient particle “accelerator” which can reach PeV energies. Today, new surprising data concerning the gamma-ray flares produced by the Crab Nebula challenge models of particle acceleration. The total energy flux from the Crab has been considered for many decades substantially stable at X-ray and gamma-ray energies. However, this paradigm was shattered by the AGILE discovery and Fermi confirmation in September 2010 of transient gamma-ray emission from the Crab. Indeed, we can state that four major flaring gamma-ray episodes have been detected by AGILE and Fermi during the period mid-2007/2012. During these events, transient particle acceleration occurs in a regime which apparently violates the MHD conditions and synchrotron cooling constraints. This fact justifies calling “super-acceleration” the mechanism which produces the “flaring Crab phenomenon”. Radiation between 50 MeV and a few GeV is emitted with a quite hard spectrum within a short timescale (hours-days), with no obvious relation with simultaneous optical and X-ray emissions in the inner Nebula. “Super-acceleration” implies overcoming synchrotron cooling by strong (and “parallel”) electric fields most likely produced by magnetic field reconnection within the pulsar wind outflow. This acceleration appears to be very efficient and, remarkably, limited by radiation reaction. It is not clear at the moment where in the Nebula this phenomenon occurs. An intense observational program is now focused on the Crab Nebula to resolve its most challenging mystery.

Final focus designs for crab waist colliders

Directory of Open Access Journals (Sweden)

A. Bogomyagkov

2016-12-01

Full Text Available The crab waist collision scheme promises significant luminosity gain. The successful upgrade of the DAΦNE collider proved the principle of crab waist collision and increased luminosity 3 times. Therefore, several new projects try to implement the scheme. The paper reviews interaction region designs with the crab waist collision scheme for already existent collider DAΦNE and SuperKEKB, presently undergoing commissioning, for the projects of SuperB in Italy, CTau in Novosibirsk and FCC-ee at CERN.

Hidden values in bauxite residue (red mud): recovery of metals.

Science.gov (United States)

Liu, Yanju; Naidu, Ravi

2014-12-01

Bauxite residue (red mud) is a hazardous waste generated from alumina refining industries. Unless managed properly, red mud poses significant risks to the local environment due to its extreme alkalinity and its potential impacts on surface and ground water quality. The ever-increasing generation of red mud poses significant challenges to the aluminium industries from management perspectives given the low proportion that are currently being utilized beneficially. Red mud, in most cases, contains elevated concentrations of iron in addition to aluminium, titanium, sodium and valuable rare earth elements. Given the scarcity of iron supply globally, the iron content of red mud has attracted increasing research interest. This paper presents a critical overview of the current techniques employed for iron recovery from red mud. Information on the recovery of other valuable metals is also reviewed to provide an insight into the full potential usage of red mud as an economic resource rather than a waste. Traditional hydrometallurgy and pyrometallurgy are being investigated continuously. However, in this review several new techniques are introduced that consider the process of iron recovery from red mud. An integrated process which can achieve multiple additional values from red mud is much preferred over the single process methods. The information provided here should help to improve the future management and utilization of red mud. Copyright © 2014 Elsevier Ltd. All rights reserved.

Geographic Variation in Camouflage Specialization by a Decorator Crab.

Science.gov (United States)

Stachowicz, John J; Hay, Mark E

2000-07-01

In North Carolina, the decorator crab Libinia dubia camouflages almost exclusively with the chemically noxious alga Dictyota menstrualis. By placing this alga on its carapace, the crab behaviorally sequesters the defensive chemicals of the plant and gains protection from omnivorous consumers. However, Dictyota is absent north of North Carolina, whereas Libinia occurs as far north as New England. Crabs from three northern locations where Dictyota is absent (Rhode Island, Connecticut, and New Jersey) camouflaged to match their environment, rather than selectively accumulating any one species. When D. menstrualis was offered to crabs from northern sites, they did not distinguish between it and other seaweeds for camouflage, whereas crabs from Alabama and two locations in North Carolina used D. menstrualis almost exclusively. In addition, in winter and spring, when Dictyota was seasonally absent in North Carolina, Libinia selectively camouflaged with the sun sponge Hymeniacidon heliophila, which was chemically unpalatable to local fishes. Thus, southern crabs were consistent specialists on chemically defended species for camouflage, while northern crabs were more generalized. The geographic shift in crab behavior away from specialization coincides with a reported decrease in both total predation pressure and the frequency of omnivorous consumers. These shifts in the nature and intensity of predation pressure may favor different camouflage strategies (generalist vs. specialist), contributing to the observed geographic differences in camouflage behavior.

The diversity of mud volcanoes in the landscape of Azerbaijan

Science.gov (United States)

Rashidov, Tofig

2014-05-01

As the natural phenomenon the mud volcanism (mud volcanoes) of Azerbaijan are known from the ancient times. The historical records describing them are since V century. More detail study of this natural phenomenon had started in the second half of XIX century. The term "mud volcano" (or "mud hill") had been given by academician H.W. Abich (1863), more exactly defining this natural phenomenon. All the previous definitions did not give such clear and capacious explanation of it. In comparison with magmatic volcanoes, globally the mud ones are restricted in distribution; they mainly locate within the Alpine-Himalayan, Pacific and Central Asian mobile belts, in more than 30 countries (Columbia, Trinidad Island, Italy, Romania, Ukraine, Georgia, Azerbaijan, Turkmenistan, Iran, Pakistan, Indonesia, Burma, Malaysia, etc.). Besides it, the zones of mud volcanoes development are corresponded to zones of marine accretionary prisms' development. For example, the South-Caspian depression, Barbados Island, Cascadia (N.America), Costa-Rica, Panama, Japan trench. Onshore it is Indonesia, Japan, and Trinidad, Taiwan. The mud volcanism with non-accretionary conditions includes the areas of Black Sea, Alboran Sea, the Gulf of Mexico (Louisiana coast), Salton Sea. But new investigations reveal more new mud volcanoes and in places which were not considered earlier as the traditional places of mud volcanoes development (e.g. West Nile Rive delta). Azerbaijan is the classic region of mud volcanoes development. From over 800 world mud volcanoes there are about 400 onshore and within the South-Caspian basin, which includes the territory of East Azerbaijan (the regions of Shemakha-Gobustan and Low-Kura River, Absheron peninsula), adjacent water area of South Caspian (Baku and Absheron archipelagoes) and SW Turkmenistan and represents an area of great downwarping with thick (over 25 km) sedimentary series. Generally, in the modern relief the mud volcanoes represent more or less large uplifts

Corrective Action Investigation Plan for Corrective Action Unit 234: Mud Pits, Cellars, and Mud Spills, Nevada Test Site, Nevada, Revision 0

International Nuclear Information System (INIS)

Grant Evenson

2007-01-01

Corrective Action Unit 234, Mud Pits, Cellars, and Mud Spills, consists of 12 inactive sites located in the north and northeast section of the NTS. The 12 CAU 234 sites consist of mud pits, mud spills, mud sumps, and an open post-test cellar. The CAU 234 sites were all used to support nuclear testing conducted in the Yucca Flat and Rainier Mesa areas during the 1950s through the 1970s. The CASs in CAU 234 are being investigated because hazardous and/or radioactive constituents may be present in concentrations that could potentially pose a threat to human health and the environment. Existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives for the CASs. Additional information will be generated by conducting a CAI before evaluating and selecting appropriate corrective action alternatives

Thermal mud maturation: organic matter and biological activity.

Science.gov (United States)

Centini, M; Tredici, M R; Biondi, N; Buonocore, A; Maffei Facino, R; Anselmi, C

2015-06-01

Many of the therapeutic and cosmetic treatments offered in spas are centred on mud therapy, to moisturize the skin and prevent skin ageing and rheumatic diseases. Thermal mud is a complex matrix composed of organic and inorganic elements which contribute to its functions. It is a natural product derived from the long mixing of clay and thermal water. During its maturation, organic substances are provided by the microalgae, which develop characteristic of the composition of thermal water. The aim of this study was to identify methods for introducing objective parameters as a basis for characterizing thermal mud and assessing its efficacy. Samples of thermal mud were collected at the Saturnia spa, where there are several sulphureous pools. The maturation of the mud was evaluated by organic component determination using extractive methods and chromatographic analysis (HPLC, GC-MS, SPME). We also studied the radical scavenging activity of mud samples at different stages of maturation, in a homogeneous phase, using several tests (DPPH, ORAC, ABTS). We identified several classes of compounds: saturated and unsaturated fatty acids, hydroxyl acids, dicarboxylic acids, ketoacids, alcohols and others. SPME analysis showed the presence of various hydrocarbons compounds (C(11) -C(17)) and long-chain alcohols (C(12) -C(16)). Six or seven months seemed appropriate to complete the process of maturation, and the main effect of maturation time was the increase of lipids. Six-month mud showed the highest activity. The hydrophilic extract was more active than the lipophilic extract. The results indicate that maturation of thermal mud can be followed on the basis of the changes in its organic composition and antioxidant properties along the time. They also highlight the need to develop reference standards for thermal muds in relation to assess their use for therapeutic and cosmetic purposes. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Are Crab nanoshots Schwinger sparks?

Energy Technology Data Exchange (ETDEWEB)

Stebbins, Albert [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Yoo, Hojin [Univ. of Wisconsin, Madison, WI (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)

2015-05-21

The highest brightness temperature ever observed are from "nanoshots" from the Crab pulsar which we argue could be the signature of bursts of vacuum e^± pair production. If so this would be the first time the astronomical Schwinger effect has been observed. These "Schwinger sparks" would be an intermittent but extremely powerful, ~10³ L_⊙, 10 PeV e^± accelerator in the heart of the Crab. These nanosecond duration sparks are generated in a volume less than 1 m³ and the existence of such sparks has implications for the small scale structure of the magnetic field of young pulsars such as the Crab. As a result, this mechanism may also play a role in producing other enigmatic bright short radio transients such as fast radio bursts.

Genetic population structure of the Japanese mitten crab Eriocheir ...

African Journals Online (AJOL)

Fragment of 376 bp at the mitochondrial ND2 gene was sequenced for 133 individuals of Japanese mitten crab, Eriocheir japonica from 17 localities of Japan and 30 individuals of Chinese mitten crab, E. sinensis from 2 localities of China. In Japanese mitten crab, sequence comparison of this segment revealed 23 ...

Mud Logging; Control geologico en perforaciones petroliferas (Mud Logging)

Energy Technology Data Exchange (ETDEWEB)

Pumarega Lafuente, J.C.

1994-12-31

Mud Logging is an important activity in the oil field and it is a key job in drilling operations, our duties are the acquisition, collection and interpretation of the geological and engineering data at the wellsite, also inform the client immediately of any significant changes in the well. (Author)

Study on irradiation treatment to drunk crab

International Nuclear Information System (INIS)

Cao Hong; Chen Xiulan; Zhai Jianqing; Bao Jianzhong; Wang Jinrong

2002-01-01

For guaranteeing the quality of irradiated drunk crab, manufacture method of the dosimeter, sample setting and taking position, irradiation time, asymmetry degree of irradiation dose, contrast of the dosimeter are discussed and some reference datum to commercialization of drunk crab's irradiation are provided

Radioactivity of peat mud used in therapy.

Science.gov (United States)

Karpińska, Maria; Mnich, Krystian; Kapała, Jacek; Bielawska, Agnieszka; Kulesza, Grzegorz; Mnich, Stanisław

2016-02-01

The aim of the study was to determine the contents of natural and artificial isotopes in peat mud and to estimate the radiation dose absorbed via skin in patients during standard peat mud treatment. The analysis included 37 samples collected from 8 spas in Poland. The measurements of isotope concentration activity were conducted with the use of gamma spectrometry methods. The skin dose in a standard peat mud bath therapy is approximately 300 nSv. The effective dose of such therapy is considered to be 22 nSv. The doses absorbed during peat mud therapy are 5 orders of magnitude lower than effective annual dose absorbed from the natural radiation background by a statistical Pole (3.5 mSv). Neither therapeutic nor harmful effect is probable in case of such a small dose of ionising radiation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Treatment of a mud pit by bioremediation.

Science.gov (United States)

Avdalović, Jelena; Đurić, Aleksandra; Miletić, Srdjan; Ilić, Mila; Milić, Jelena; Vrvić, Miroslav M

2016-08-01

The mud generated from oil and natural gas drilling, presents a considerable ecological problem. There are still insufficient remedies for the removal and minimization of these very stable emulsions. Existing technologies that are in use, more or less successfully, treat about 20% of generated waste drilling mud, while the rest is temporarily deposited in so-called mud pits. This study investigated in situ bioremediation of a mud pit. The bioremediation technology used in this case was based on the use of naturally occurring microorganisms, isolated from the contaminated site, which were capable of using the contaminating substances as nutrients. The bioremediation was stimulated through repeated inoculation with a zymogenous microbial consortium, along with mixing, watering and biostimulation. Application of these bioremediation techniques reduced the concentration of total petroleum hydrocarbons from 32.2 to 1.5 g kg(-1) (95% degradation) during six months of treatment. © The Author(s) 2016.

Experimental study on rule of radioactive change of red mud concrete

Science.gov (United States)

Wu, Bin; Tan, Zhuoying; Yu, Zhongtao

2017-12-01

Red mud was used to partially replace cement to prepare red mud concrete, with replacement rate of red mud mass being 0%, 5%, 10%, 15% and 20% respectively, and hydration age being 3d, 28d and 90d. The experiment of cube compressive strength and radioactivity were conducted for 90 cubical test pieces respectively. The results show that with rise of replacement rate of red mud, the cube compressive strength of red mud concrete at the same hydration age first increased and then decreased, leading to increase of content of 226Ra,232Th,40K in red mud concrete, and increase of material’s radioactivity accordingly; as hydration age was prolonged, with the replacement rate of red mud being the same, the compressive strength increased, and internal and external exposure indices and total specific activity all increased yet with small increase range. Generally the hydration age does not significantly influence the radioactivity of red mud concrete.

The effects of drilling muds on marine invertebrate larvae and adults

International Nuclear Information System (INIS)

Raimondi, P.T.; Barnett, A.M.; Krause, P.R.

1997-01-01

A series of laboratory experiments tested the effects of drilling muds from an active platform off southern California on larvae and adults of marine invertebrates. Red abalone (Haliotis rufescens) were used to determine effects of drilling muds on fertilization, early development, survivorship, and settlement, and experiments on adult brown cup corals (Paracyathus stearnsii) tested effects on adult survivorship, viability, and tissue loss. Exposures to drilling muds did not have an effect on abalone fertilization or early development. However, several exposures to drilling muds resulted in weak, but significant, positive effects of drilling muds on settlement of competent larvae. In contrast, settlement of red abalone larvae on natural coralline algal crusts decreased with increasing concentrations of drilling muds. This suggests that drilling muds affect either the abalone's ability to detect natural settlement inducers, or they affect the inducer itself. Exposure of brown cup corals to concentrations of drilling muds adversely impacted their survivorship and viability. These effects were likely caused by increased tissue mortality of the coral polyps

CLIC crab cavity design optimisation for maximum luminosity

Energy Technology Data Exchange (ETDEWEB)

Dexter, A.C., E-mail: a.dexter@lancaster.ac.uk [Lancaster University, Lancaster, LA1 4YR (United Kingdom); Cockcroft Institute, Daresbury, Warrington, WA4 4AD (United Kingdom); Burt, G.; Ambattu, P.K. [Lancaster University, Lancaster, LA1 4YR (United Kingdom); Cockcroft Institute, Daresbury, Warrington, WA4 4AD (United Kingdom); Dolgashev, V. [SLAC, Menlo Park, CA 94025 (United States); Jones, R. [University of Manchester, Manchester, M13 9PL (United Kingdom)

2011-11-21

The bunch size and crossing angle planned for CERN's compact linear collider CLIC dictate that crab cavities on opposing linacs will be needed to rotate bunches of particles into alignment at the interaction point if the desired luminosity is to be achieved. Wakefield effects, RF phase errors between crab cavities on opposing linacs and unpredictable beam loading can each act to reduce luminosity below that anticipated for bunches colliding in perfect alignment. Unlike acceleration cavities, which are normally optimised for gradient, crab cavities must be optimised primarily for luminosity. Accepting the crab cavity technology choice of a 12 GHz, normal conducting, travelling wave structure as explained in the text, this paper develops an analytical approach to optimise cell number and iris diameter.

A large bubble around the Crab Nebula

Science.gov (United States)

Romani, Roger W.; Reach, William T.; Koo, Bon Chul; Heiles, Carl

1990-01-01

IRAS and 21 cm observations of the interstellar medium around the Crab nebula show evidence of a large bubble surrounded by a partial shell. If located at the canonical 2 kpc distance of the Crab pulsar, the shell is estimated to have a radius of about 90 pc and to contain about 50,000 solar masses of swept-up gas. The way in which interior conditions of this bubble can have important implications for observations of the Crab are described, and the fashion in which presupernova evolution of the pulsar progenitor has affected its local environment is described.

Red mud characterization using nuclear analytical techniques

International Nuclear Information System (INIS)

Obhodas, J.; Sudac, D.; Matjacic, L.; Valkovic, V.

2011-01-01

Red mud is a toxic waste left as a byproduct in aluminum production Bayer process. Since it contains significant concentrations of other chemical elements interesting for industry, including REE, it is also potential secondary ore source. Recent events in some countries have shown that red mud presents a serious environmental hazard if not properly stored. The subject of our study is the red mud from an ex-aluminum plant in Obrovac, Croatia, left from processing of bauxite mined during late 70's and early 80's at the eastern Adriatic coast and since than stored in open concrete basins for more than 30 years. We have used energy dispersive x-ray fluorescence analysis (both tube and radioactive source excitation), fast neutron activation analysis and passive gamma spectrometry to identify a number of elements present in the red mud, their concentration levels and radioactivity in the red mud. The high concentrations of Al, Si, Ca, Ti and Fe have been measured. Chemical elements Sc, Cr, Mn, Co, Ni, Cu, Zn, Ga, As, Se, Br, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Pb, Th and U were found in lower concentrations. No significant levels of radioactivity have been measured. (authors)

Elementary concentration of Peruibe black mud by neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Torrecilha, Jefferson K.; Ponciano, Ricardo; Silva, Paulo S.C da, E-mail: jeffkoy@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil)

2013-07-01

The Peruibe Black Mud is used in therapies such as psoriasis, peripheral dermatitis, acne, seborrehea, myalgia arthritis and rheumatic non-articular processes. This material is characterized by is fine organic matter particles, sulphate reducing bacteria and a high content of potential reduction ions. Although this material is particles, sulphate reducing bacteria and a high content of potential reduction ions. Although this material is considered natural, it may not be free of possible adverse health effects, like toxic chemical elements, when used for therapeutic purposes. In the therapeutic treatments involving clays, clays are used in mud form also called peloids, obtained by maturation process. Five in natura and three maturated Black Mud samples were collected in Peruibe city, Sao Paulo State, Brazil. To investigate the distribution of major, trace and rare earth elements in the in natura and maturated clays that constitute the Peruibe Black Mud, neutron activation analysis (NAA) was used. A comparison between in natura and maturated mud shows that major, trace and rare earth elements follow the same order in both types. Generally, the concentrations in the maturated mud are slightly lower than in natura mud. Enrichment on the upper continental crust could be observed for the elements As, Br, Sb and Se, in these types of mud. (author)

The identification of immune genes in the milk transcriptome of the Tasmanian devil (Sarcophilus harrisii

Directory of Open Access Journals (Sweden)

Rehana V. Hewavisenti

2016-01-01

Full Text Available Tasmanian devil (Sarcophilus harrisii pouch young, like other marsupials, are born underdeveloped and immunologically naïve, and are unable to mount an adaptive immune response. The mother’s milk provides nutrients for growth and development as well as providing passive immunity. To better understand immune response in this endangered species, we set out to characterise the genes involved in passive immunity by sequencing and annotating the transcriptome of a devil milk sample collected during mid-lactation. At mid-lactation we expect the young to have heightened immune responses, as they have emerged from the pouch, encountering new pathogens. A total of 233,660 transcripts were identified, including approximately 17,827 unique protein-coding genes and 846 immune genes. The most highly expressed transcripts were dominated by milk protein genes such as those encoding early lactation protein, late lactation proteins, α-lactalbumin, α-casein and β-casein. There were numerous highly expressed immune genes including lysozyme, whey acidic protein, ferritin and major histocompatibility complex I and II. Genes encoding immunoglobulins, antimicrobial peptides, chemokines and immune cell receptors were also identified. The array of immune genes identified in this study reflects the importance of the milk in providing immune protection to Tasmanian devil young and provides the first insight into Tasmanian devil milk.

Aluminium leaching from red mud by filamentous fungi.

Science.gov (United States)

Urík, Martin; Bujdoš, Marek; Milová-Žiaková, Barbora; Mikušová, Petra; Slovák, Marek; Matúš, Peter

2015-11-01

This contribution investigates the efficient and environmentally friendly aluminium leaching from red mud (bauxite residue) by 17 species of filamentous fungi. Bioleaching experiments were examined in batch cultures with the red mud in static, 7-day cultivation. The most efficient fungal strains in aluminium bioleaching were Penicillium crustosum G-140 and Aspergillus niger G-10. The A. niger G-10 strain was capable to extract up to approximately 141 mg·L(-1) of aluminium from 0.2 g dry weight red mud. Chemical leaching with organic acids mixture, prepared according to A. niger G-10 strain's respective fungal excretion during cultivation, proved that organic acids significantly contribute to aluminium solubilization from red mud. Copyright © 2015 Elsevier Inc. All rights reserved.

New insights into the sorption mechanism of cadmium on red mud

International Nuclear Information System (INIS)

Luo Lei; Ma Chenyan; Ma Yibing; Zhang Shuzhen; Lv Jitao; Cui Mingqi

2011-01-01

Effectiveness and mechanism of cadmium (Cd) sorption on original, acidified and ball milling nano-particle red muds were investigated using batch sorption experiments, sequential extraction analysis and X-ray absorption near edge structure (XANES) spectroscopy. The maximum sorption capacity of Cd was 0.16, 0.19, and 0.21 mol/kg for the original, acidified, and nano-particle red muds at pH 6.5, respectively. Both acidification and ball-milling treatments significantly enhanced Cd sorption and facilitated transformation of Cd into less extractable fractions. The Cd L III -edge XANES analysis indicated the formation of inner-sphere complexes of Cd similar to XCdOH (X represents surface groups on red mud) on the red mud surfaces although outer-sphere complexes of Cd were the primary species. This work shed light on the potential application of red mud to remediate Cd-contaminated soils and illustrated the promising tool of XANES spectroscopy for speciation of multicomponent systems of environmental relevance. - Graphical abstract: Display Omitted Highlights: → Red mud has a strong affinity for Cd contaminants. → Ball-milling treatments significantly enhance Cd sorption on red mud. → Cadmium partially formed inner-sphere complexes on the red mud surfaces. → Red mud can be used to remediate Cd contaminated soils effectively. - Cadmium can be strongly sorbed and partially forms inner-sphere complexes on red mud.

Ghost crabs on a treadmill: Oxygen Uptake and Haemocyanin ...

African Journals Online (AJOL)

Ghost crabs Ocypode ceratophthalmus were exercised on a specially constructed treadmill. At a running speed of 13,3 cm s-1, most crabs ran for 2 h before getting fatigued. At this speed the oxygen consumption rate (MO2) was measured in time intervals for a total of 52 min. For exercised crabs the MO2 values are about ...

Marvelous Mud

Science.gov (United States)

Keeler, Rusty

2011-01-01

The author visited the Open Spaces Preschool in Whangarei, New Zealand and was surprised to see the most amazing natural preschool play. There were six preschoolers stripped down to tee shirts and underpants slipping, slopping, and sliding in the dirt spot which had now become the most lovely, silky-smooth deep-brown mud ever. Studies have…

Mud Volcanoes as Exploration Targets on Mars

Science.gov (United States)

Allen, Carlton C.; Oehler, Dorothy Z.

2010-01-01

Tens of thousands of high-albedo mounds occur across the southern part of the Acidalia impact basin on Mars. These structures have geologic, physical, mineralogic, and morphologic characteristics consistent with an origin from a sedimentary process similar to terrestrial mud volcanism. The potential for mud volcanism in the Northern Plains of Mars has been recognized for some time, with candidate mud volcanoes reported from Utopia, Isidis, northern Borealis, Scandia, and the Chryse-Acidalia region. We have proposed that the profusion of mounds in Acidalia is a consequence of this basin's unique geologic setting as the depocenter for the tune fraction of sediments delivered by the outflow channels from the highlands.

Ferroacryl mud for drilling deep bore holes

Energy Technology Data Exchange (ETDEWEB)

Lisyanskiy, V I; Chepiga, V I; Devydenko, V N

1982-01-01

The composition, technology of production and control of the parameters of a ferroacyl (FAR) mud for drilling for prospecting holes in the Donets-Basin are developed. The mud consists of Chasov Yal clay (150-160 kg), hypane (40 1), iron sulfate (1kg) and water (approximately 1 m/sup 3/). The mud exhibits the following parameters: density 1.05 -1.1 g/cm/sup 3/, viscosity 20-21 s; water yield 3-5 cm/sup 3/; crust 0.5 mm. Compared to existing flushing fluids based on hypane the FAR contains fewer components and the cost of the materials is considerably less. It features very high flocculating properties.

A Bingham-plastic model for fluid mud transport under waves and currents

Science.gov (United States)

Liu, Chun-rong; Wu, Bo; Huhe, Ao-de

2014-04-01

Simplified equations of fluid mud motion, which is described as Bingham-Plastic model under waves and currents, are presented by order analysis. The simplified equations are non-linear ordinary differential equations which are solved by hybrid numerical-analytical technique. As the computational cost is very low, the effects of wave current parameters and fluid mud properties on the transportation velocity of the fluid mud are studied systematically. It is found that the fluid mud can move toward one direction even if the shear stress acting on the fluid mud bed is much smaller than the fluid mud yield stress under the condition of wave and current coexistence. Experiments of the fluid mud motion under current with fluctuation water surface are carried out. The fluid mud transportation velocity predicted by the presented mathematical model can roughly match that measured in experiments.

Biota - 2011 Vegetation Inventory - Mud Lake, MN/SD

Data.gov (United States)

Army Corps of Engineers, Department of the Army, Department of Defense — 2011 Vegetation Classification for Mud Lake, MN/SD Vegetation Project Report, OMBIL Environmental Stewardship - Level 1 Inventory. Mud Lake, located on the Minnesota...

VIH from the mud crab is specifically expressed in the eyestalk and potentially regulated by transactivator of Sox9/Oct4/Oct1.

Science.gov (United States)

Liu, Chunyun; Jia, Xiwei; Zou, Zhihua; Wang, Xiaowei; Wang, Yilei; Zhang, Ziping

2018-01-01

Vitellogenesis-inhibiting hormone (VIH) is known to regulate ovarian maturation by suppressing the synthesis of vitellogenin (Vtg) in crustaceans, which belongs to a member of crustacean hyperglycemic hormone (CHH) family synthesized and secreted from the X-organ/sinus gland complex of eyestalks. In this study, the cDNA, genomic DNA (gDNA) and the 5'-upstream regulatory (promoter region) sequences of VIH gene were obtained by conventional PCR, genome walker and tail-PCR techniques according to our transcriptomic database of Scylla paramamosain. The full-length cDNA of SpVIH is 634bp including 105bp 5'UTR, 151bp 3'UTR and 378bp ORF that encodes a peptide of 125 amino acids. The full length gDNA of SpVIH is 790bp containing two exons and one intron. The 5'-flanking promoter regions of SpVIH we isolated are 3070bp from the translation initiation (ATG) and 2398bp from the predicted transcription initiation (A), which consists of putative core promoter region and multiple potential transcription factor binding sites. SpVIH was only expressed in eyestalk. The expression level of SpVIH in eyestalk of female crab decreased gradually along with the development of ovary. As there is not cell line of crabs available, we chose the mature transfection system HEK293FT cell lines to explore the mechanism of transcription regulation of SpVIH in crabs. Sequential deletion assays using luciferase reporter gene in HEK293FT cells revealed that the possible promoter activity regions (including positive and negative transcription factors binding sites simultaneously) presented between pSpVIH-4 and pSpVIH-6. In order to further identify the crucial transcription factors binding site in this region, the site-directed mutagenesis of Sox9/Oct4/Oct1 binding site of pSpVIH-4 was created. The results demonstrated that the transcriptional activity of pSpVIH-4△ decreased significantly (p<0.05). Thus, it is reasonable to deduce that the Sox9/Oct4/Oct1 may be the essential positive transcription

A reagent for processing drilling muds

Energy Technology Data Exchange (ETDEWEB)

Polyakov, G.A.; Khon-Pak, A.T.; Khon, A.V.; Normatov, L.N.; Telegin, B.V.

1983-01-01

A reagent is proposed for processing drilling muds. It contains an acrylic polymer and potassium permanganate. The reagent is distinguished by the fact that in order to improve the quality of the drilling muds by increasing their salt resistance, the reagent contains hydrolized nitron fiber as the acrylic polymer with the following component relationship (in percent by weight): potassium permanganate, 0.015 to 0.065 and hydrolyzed nitron fiber, the remainder.

Antimicrobial lipids from the hemolymph of brachyuran crabs

Digital Repository Service at National Institute of Oceanography (India)

Ravichandran, S.; Wahidullah, S.; DeSouza, L.; Rameshkumar, G.

The potential of marine crabs as a source of biologically active products is largely unexplored. In the present study, antimicrobial activity of the hemolymph (plasma) and hemocytes (plasma cells) of six brachyuran crabs was investigated against 16...

Red mud as a carbon sink: variability, affecting factors and environmental significance.

Science.gov (United States)

Si, Chunhua; Ma, Yingqun; Lin, Chuxia

2013-01-15

The capacity of red mud to sequester CO(2) varied markedly due to differences in bauxite type, processing and disposal methods. Calcium carbonates were the dominant mineral phases responsible for the carbon sequestration in the investigated red mud types. The carbon sequestration capacity of red mud was not fully exploited due to shortages of soluble divalent cations for formation of stable carbonate minerals. Titanate and silicate ions were the two major oxyanions that appeared to strongly compete with carbonate ions for the available soluble Ca. Supply of additional soluble Ca and Mg could be a viable pathway for maximizing carbon sequestration in red mud and simultaneously reducing the causticity of red mud. It is roughly estimated that over 100 million tonnes of CO(2) have been unintentionally sequestered in red mud around the world to date through the natural weathering of historically produced red mud. Based on the current production rate of red mud, it is likely that some 6 million tonnes of CO(2) will be sequestered annually through atmospheric carbonation. If appropriate technologies are in place for incorporating binding cations into red mud, approximately 6 million tonnes of additional CO(2) can be captured and stored in the red mud while the hazardousness of red mud is simultaneously reduced. Copyright © 2012 Elsevier B.V. All rights reserved.

Emittance Growth due to Crab Cavity Ramping for LHC Beam-1 Lattice

CERN Document Server

Morita, A

2008-01-01

In LHC upgrade scenarios using global crab crossing, it is desired to turn on the crab cavity only at top energy. Turning on the crab cavity could increase the emittance of the stored beam, since the transverse kick of the crab cavity excites betatron oscillations. For a sufficiently slow ramping speed of the crab cavity voltage, however, the changes in z-dependent closed orbit are sufficiently adiabatic that the emittance growth becomes negligible. In order to determine the safe ramping speed of the LHC crab-cavity voltage, the dependence of the emittance growth on the ramping speed is estimated via a 6D particle-tracking simulation.

Status of LHC crab activity simulations and beam studies

International Nuclear Information System (INIS)

Calaga, R.; Assman, R.; Barranco, J.; Barranco, J.; Calaga, R.; Caspers, F.; Ciapala, E.; De-Maria, R.; Koutchouk, J. P.; Linnecar, T.; Metral, E.; Morita, A.; Solyak, N.; Sun, Y.; Tomas, R.; Tuckmantel, J.; Weiler, T.; Zimmermann, F.

2009-01-01

The LHC crab cavity program is advancing rapidly towards a first prototype which is anticipated to be tested during the early stages of the LHC phase I upgrade and commissioning. The general project status and some aspects related to crab optics, collimation, aperture constraints, impedances, noise effects. beam transparency and machine protection critical for a safe and robust operation of LHC beams with crab cavities are addressed here

Comparison of Copper Scavenging Capacity between Two Different Red Mud Types

Directory of Open Access Journals (Sweden)

Yingqun Ma

2012-09-01

Full Text Available A batch experiment was conducted to compare the Cu scavenging capacity between two different red mud types: the first one was a highly basic red mud derived from a combined sintering and Bayer process, and the second one was a seawater-neutralized red mud derived from the Bayer process. The first red mud contained substantial amounts of CaCO3, which, in combination with the high OH− activity, favored the immobilization of water-borne Cu through massive formation of atacamite. In comparison, the seawater-neutralized red mud had a lower pH and was dominated by boehmite, which was likely to play a significant role in Cu adsorption. Overall, it appears that Cu was more tightly retained by the CaCO3-dominated red mud than the boehmite-dominated red mud. It is concluded that the heterogeneity of red mud has marked influences on its capacity to immobilize water-borne Cu and maintain the long-term stability of the immobilized Cu species. The research findings obtained from this study have implications for the development of Cu immobilization technology by using appropriate waste materials generated from the aluminium industry.

Comparison of Copper Scavenging Capacity between Two Different Red Mud Types

Science.gov (United States)

Ma, Yingqun; Si, Chunhua; Lin, Chuxia

2012-01-01

A batch experiment was conducted to compare the Cu scavenging capacity between two different red mud types: the first one was a highly basic red mud derived from a combined sintering and Bayer process, and the second one was a seawater-neutralized red mud derived from the Bayer process. The first red mud contained substantial amounts of CaCO3, which, in combination with the high OH− activity, favored the immobilization of water-borne Cu through massive formation of atacamite. In comparison, the seawater-neutralized red mud had a lower pH and was dominated by boehmite, which was likely to play a significant role in Cu adsorption. Overall, it appears that Cu was more tightly retained by the CaCO3-dominated red mud than the boehmite-dominated red mud. It is concluded that the heterogeneity of red mud has marked influences on its capacity to immobilize water-borne Cu and maintain the long-term stability of the immobilized Cu species. The research findings obtained from this study have implications for the development of Cu immobilization technology by using appropriate waste materials generated from the aluminium industry.

The surprising Crab pulsar and its nebula: a review.

Science.gov (United States)

Bühler, R; Blandford, R

2014-06-01

The Crab nebula and its pulsar (referred to together as 'the Crab') have historically played a central role in astrophysics. True to this legacy, several unique discoveries have been made recently. The Crab was found to emit gamma-ray pulsations up to energies of 400 GeV, beyond what was previously expected from pulsars. Strong gamma-ray flares, of durations of a few days, were discovered from within the nebula, while the source was previously expected to be stable in flux on these time scales. Here we review these intriguing and suggestive developments. In this context we give an overview of the observational properties of the Crab and our current understanding of pulsars and their nebulae.

Potential environmental benefits from regulatory consideration of synthetic drilling muds

International Nuclear Information System (INIS)

Burke, C.J.; Veil, J.A.

1995-02-01

When drilling exploration and production wells for oil and gas, drillers use specialized drilling fluids, referred to as muds, to help maintain well control and to remove drill cuttings from the hole. Historically, either water-based muds (WBMs) or oil-based muds (OBMs) have been used for offshore wells. Recently, in response to US Environmental Protection Agency (EPA) regulations and drilling-waste discharge requirements imposed by North Sea nations, the drilling industry has developed several types of synthetic-based muds (SBMs) that combine the desirable operating qualities of OBMs with the lower toxicity and environmental impact qualities of WBMs. This report describes the operational, environmental, and economic features of all three types of muds and discusses potential EPA regulatory barriers to wider use of SBMs

Molecular characterization of Cryptosporidium and Giardia from the Tasmanian devil (Sarcophilus harrisii).

Science.gov (United States)

Wait, Liana F; Fox, Samantha; Peck, Sarah; Power, Michelle L

2017-01-01

The Tasmanian devil (Sarcophilus harrisii) is a carnivorous marsupial found only in the wild in Tasmania, Australia. Tasmanian devils are classified as endangered and are currently threatened by devil facial tumour disease, a lethal transmissible cancer that has decimated the wild population in Tasmania. To prevent extinction of Tasmanian devils, conservation management was implemented in 2003 under the Save the Tasmanian Devil Program. This study aimed to assess if conservation management was altering the interactions between Tasmanian devils and their parasites. Molecular tools were used to investigate the prevalence and diversity of two protozoan parasites, Cryptosporidium and Giardia, in Tasmanian devils. A comparison of parasite prevalence between wild and captive Tasmanian devils showed that both Cryptosporidium and Giardia were significantly more prevalent in wild devils (p Giardia was identified in 24.1% of wild devils but only 0.82% of captive devils. Molecular analysis identified the presence of novel genotypes of both Cryptosporidium and Giardia. The novel Cryptosporidium genotype was 98.1% similar at the 18S rDNA to Cryptosporidium varanii (syn. C. saurophilum) with additional samples identified as C. fayeri, C. muris, and C. galli. Two novel Giardia genotypes, TD genotype 1 and TD genotype 2, were similar to G. duodenalis from dogs (94.4%) and a Giardia assemblage A isolate from humans (86.9%). Giardia duodenalis BIV, a zoonotic genotype of Giardia, was also identified in a single captive Tasmanian devil. These findings suggest that conservation management may be altering host-parasite interactions in the Tasmanian devil, and the presence of G. duodenalis BIV in a captive devil points to possible human-devil parasite transmission.

Particle beam and crabbing and deflecting structure

Science.gov (United States)

Delayen, Jean [Yorktown, VA

2011-02-08

A new type of structure for the deflection and crabbing of particle bunches in particle accelerators comprising a number of parallel transverse electromagnetic (TEM)-resonant) lines operating in opposite phase from each other. Such a structure is significantly more compact than conventional crabbing cavities operating the transverse magnetic TM mode, thus allowing low frequency designs.

Bioactive substances of the Techirghiol therapeutic mud

Directory of Open Access Journals (Sweden)

Mihail Hoteteu

2018-02-01

Full Text Available The study aims to characterize Techirghiol's sapropelic mud both by determining the organic and inorganic composition of the constituent phases and by isolating some compounds of humic substances. The distribution between the solid and liquid phases of the peloid of the Ca2+, Mg2+, Fe3+cations, PO43- anion, bioactive compounds of the protein, lipid and carbohydrate classes as well as the phosphatase activity of Techirghiol sapropelic mud are analyzed. The mud is fractionated using the pH and solvent polarity variation and is spectrophotometrically characterized based on absorption in the wavelength range 340-700 nm humic acids and fulvic acids differentiated on the basis of solubility and molecular mass.

Irradiation of residual muds and its use in the oat cultivation

International Nuclear Information System (INIS)

Moreno, A.J.; Colin, C.A.; Gomeztagle, M.M.; Frias, P.H.

1997-01-01

The irradiation of residual muds samples from a wastewater treatment plant at gamma radiation dose of 15 kGy removes from muds on average: fats and oils (33%), detergent (92%), phenols (50%) and over 99% of microorganisms of total account. The evaluation of irradiated residual mud and without irradiation as soil conditioner in oat growing (avena safira), was realized by triplicate, using different rates (80, 60, 40 and 20%) of frank sandy soil and irradiated and non-irradiated residual mud. The growing with rates 60/40 % of soil and irradiated mud respectively, resulted being more adequate as soil conditioner. It is important to clarify that for putting residual mud it is necessary that metals concentration not exceed the maximum permissible levels for the soil type and the corresponding growing. (Author)

Feasibility study for an innovative industrial red mud utilisation method.

Science.gov (United States)

Kounalakis, Petros; Aravossis, Konstantinos; Karayianni, ChS

2016-02-01

Red mud is a high volume industrial waste, and its management poses a unique challenge. For the utilisation of red mud, an economical, energy saving, environmental friendly and widely applicable method has been found. The proposed novel method is purely chemical, and achieves the recovery of all the oxides contained in red mud totally and transforms them into high value added products. The present work shows that an investment in an industrial plant, treating red mud and turning a toxic industrial waste in commercial products, is safe and viable. © The Author(s) 2015.

Land crabs as key drivers in tropical coastal forest recruitment

Science.gov (United States)

Lindquist, E.S.; Krauss, K.W.; Green, P.T.; O'Dowd, D. J.; Sherman, P.M.; Smith, T. J.

2009-01-01

Plant populations are regulated by a diverse assortment of abiotic and biotic factors that influence seed dispersal and viability, and seedling establishment and growth at the microsite. Rarely does one animal guild exert as significant an influence on different plant assemblages as land crabs. We review three tropical coastal ecosystems-mangroves, island maritime forests, and mainland coastal terrestrial forests-where land crabs directly influence forest composition by limiting tree establishment and recruitment. Land crabs differentially prey on seeds, propagules and seedlings along nutrient, chemical and physical environmental gradients. In all of these ecosystems, but especially mangroves, abiotic gradients are well studied, strong and influence plant species distributions. However, we suggest that crab predation has primacy over many of these environmental factors by acting as the first limiting factor of tropical tree recruitment to drive the potential structural and compositional organisation of coastal forests. We show that the influence of crabs varies relative to tidal gradient, shoreline distance, canopy position, time, season, tree species and fruiting periodicity. Crabs also facilitate forest growth and development through such activities as excavation of burrows, creation of soil mounds, aeration of soils, removal of leaf litter into burrows and creation of carbon-rich soil microhabitats. For all three systems, land crabs influence the distribution, density and size-class structure of tree populations. Indeed, crabs are among the major drivers of tree recruitment in tropical coastal forest ecosystems, and their conservation should be included in management plans of these forests. ?? 2009 Cambridge Philosophical Society.

Mud depocenters on continental shelves—appearance, initiation times, and growth dynamics

Science.gov (United States)

Hanebuth, Till J. J.; Lantzsch, Hendrik; Nizou, Jean

2015-12-01

Mud accumulates on continental shelves under a variety of environmental conditions and results in a diverse formation of mud depocenters (MDCs). Their three-dimensional architectures have been in the focus of several recent studies. Due to some terminological confusion concerning MDCs, the present study sets out to define eight individual MDC types in terms of surface sediment distribution and internal geometry. Under conditions of substantial sediment supply, prodeltas (distal zones off river deltas; triangular sheets), subaqueous deltas (disconnected from deltas by strong normal-to-shore currents; wedge-like clinoforms), and mud patches (scattered distribution) and mud blankets (widespread covers) are formed. Forced by hydrodynamic conditions, mud belts in the strict sense (detached from source; elongated bodies), and shallow-water contourite drifts (detached from source; growing normal to prevailing current direction; triangular clinoforms) develop. Controlled by local morphology, mud entrapments (in depressions, behind morphological steps) and mud wedges (triangular clinoforms growing in flow direction) are deposited. Shelf mud deposition took place (1) during early outer-shelf drowning (~14 ka), (2) after inner-shelf inundation to maximum flooding (9.5-6.5 ka), and (3) in sub-recent times (near the fluvial source, (2) uni-directional, extending along advective current transport paths, and (3) progradational, forming clinoforms that grow either parallel or normal to the bottom current direction. Classical mud belts may be initiated around defined nuclei, the remote sites of which are determined by seafloor morphology rather than the location of the source. From a stratigraphic perspective, mud depocenters coincide with sea-level highstand-related, shelf-wide condensed sections. They often show a conformable succession from transgressive to highstand systems tract stages.

Stock structure and demographic history of the Indo-West Pacific mud crab Scylla serrata

Science.gov (United States)

Fratini, Sara; Ragionieri, Lapo; Cannicci, Stefano

2010-01-01

The increasing exploitation of mangrove forests, without any sustainable planning, has been seriously compromising the survival of this ecosystem and of its exclusive resources. Scylla serrata is one of the most commercially exploited crabs inhabiting mangroves and estuaries of the Indo-Pacific region. This species is extensively harvested, mainly for selling to the tourist market, and, as a consequence, its populations are in constant decline. The aim of the present study was to assess the level of genetic exchange of S. serrata within the Western Indian Ocean (WIO), using a population genetic structure approach. To achieve this goal, we reconstructed the intra-specific geographic pattern of genetic variation by partial sequencing the mitochondrial DNA cytochrome oxidase subunit I, in samples from seven mangrove sites of the WIO. Our data set then encompassed all the sequences for the same genetic marker deposited in Genbank and corresponding to samples from South East Asia, Australia and some Pacific Islands: this allowed us to estimate the level of connectivity among S. serrata populations within its distribution area. Our results show that an unique Scylla serrata metapopulation exists within the WIO; while throughout the entire Indo-Pacific region at least three distinct genetic stocks occur, corresponding to well-defined geographic regions (WIO, Eastern Australia and Pacific Ocean, North-Western Australia). South East China appears as the depositary of the most ancient haplotype and at the present time shares a haplotype with the Red Sea. The WIO populations show the signature of recent population bottlenecks, as expected for populations deeply exploited in a recent past. On the basis of our results, we can conclude that both the S. serrata populations and their habitats, i.e. mangrove forests and estuaries, of the WIO require future management and conservation regulations to avoiding overexploitation of this important key predator and marketable resource.

Mechanism of high-temperature resistant water-base mud

Energy Technology Data Exchange (ETDEWEB)

Luo, P

1981-01-01

Based on experiments, the causes and laws governing the changes in the performance of water-base mud under high temperature are analyzed, and the requisites and mechanism of treating agents resisting high temperature are discussed. Ways and means are sought for inhibiting, delaying and making use of the effect of high temperature on the performance of mud, while new ideas and systematic views have been expressed on the preparation of treating agents and set-up of a high temperature resistant water-base mud system. High temperature dispersion and high temperature surface inactivation of clay in the mud, as well as their effect and method of utilization are reviewed. Subjects also touched upon include degradation and cross-linking of the high-temperature resistant treating agents, their use and effect. Based on the above, the preparation of a water-base and system capable of resisting 180 to 250/sup 0/C is recommended.

Heavy metals distribution in the Dead Sea black mud, Jordan

International Nuclear Information System (INIS)

Momani, K.; El-Hasan, T.; Auaydeh, S.

2009-01-01

The concentrations of trace metals (Fe, Mn, Ni, Zn, Co, Cr, Cu and Pb) were investigated in the Dead Sea black mud and river sediments in the northern basin of the Dead Sea region, Jordan. The pH of the mud was slightly above 8 while it was around 6 for the seawater. All analyzed heavy metal content in the black mud, except Pb, was less than their contents in other types of mud. Tlis might be due to the effect of the mildly acideic pH of seawater, which would enhance the metal solubility or incorporation within salt mineral structure, rather than precipitation. The sequential extraction results showed that Ni and Co transferred into the carbonate fraction, Mn is found mostly as manganese-iron oxide, and the residual phase contained Cr, Cu, Fe,and Pb. This study illustrated that the black mud had low heavy metal contents, thus indicating low toxicity. additionally, it shows insignificance effect of the mixing of freshwater with seawater on the heavy metal contents in the black mud. (authors).

Mud Brick Resilience

DEFF Research Database (Denmark)

Johannessen, Runa

2012-01-01

In the seemingly endless circle of demolition and illegal rebuilding hand-made mud bricks produced from the soil of contested territory become an act of resistance. In June 2011, the Palestinian village Fasayel encountered the Israeli military’s demolition of 21 of the village’s built structures....

Drilling mud

Energy Technology Data Exchange (ETDEWEB)

Babets, M A; Nechayev, N D; Vinogradova, G P

1982-01-01

A drilling mud is proposed which contains clay, alkali, water and stabilizer reagent. It is distinguished by the fact that in order to improve the viscosity and static shear stress, the stabilizer reagent contained is composted solid general wastes with the following ratio of components (% by weight): clay 10-15, alkali 0.1-0.2; composted solid general wastes 2-5; water--the rest.

The relationship of blue crab abundance to winter mortality of Whooping Cranes

Science.gov (United States)

Pugesek, Bruce H.; Baldwin, Michael J.; Stehn, Thomas

2013-01-01

We sampled blue crab (Callinectes sapidus) numbers in marshes on the Aransas National Wildlife Refuge, Texas from 1998-2006, while simultaneously censusing the wintering population of Whooping Cranes (Grus americana) on the refuge and surrounding habitats. This was done to determine whether mortality of wintering Whooping Cranes was related to the availability of this food source. Yearly variation in crab numbers was high, ranging from a low of 0.1 crabs to a high of 3.4 crabs per 100-m transect section. Significant non-linear increases in both juvenile and adult mortality in relation to decreasing crab abundance was observed. Results suggest that some threshold of crab abundance exists in which Whooping Cranes have higher survival on their wintering grounds.

Efficient Monitoring of CRAB Jobs at CMS

Energy Technology Data Exchange (ETDEWEB)

Silva, J. M.D. [Sao Paulo, IFT; Balcas, J. [Caltech; Belforte, S. [INFN, Trieste; Ciangottini, D. [INFN, Perugia; Mascheroni, M. [Fermilab; Rupeika, E. A. [Vilnius U.; Ivanov, T. T. [Sofiya U.; Hernandez, J. M. [Madrid, CIEMAT; Vaandering, E. [Fermilab

2017-11-22

CRAB is a tool used for distributed analysis of CMS data. Users can submit sets of jobs with similar requirements (tasks) with a single request. CRAB uses a client-server architecture, where a lightweight client, a server, and ancillary services work together and are maintained by CMS operators at CERN. As with most complex software, good monitoring tools are crucial for efficient use and longterm maintainability. This work gives an overview of the monitoring tools developed to ensure the CRAB server and infrastructure are functional, help operators debug user problems, and minimize overhead and operating cost. This work also illustrates the design choices and gives a report on our experience with the tools we developed and the external ones we used.

Optimization of Mud Hammer Drilling Performance--A Program to Benchmark the Viability of Advanced Mud Hammer Drilling

Energy Technology Data Exchange (ETDEWEB)

Arnis Judzis

2006-03-01

Operators continue to look for ways to improve hard rock drilling performance through emerging technologies. A consortium of Department of Energy, operator and industry participants put together an effort to test and optimize mud driven fluid hammers as one emerging technology that has shown promise to increase penetration rates in hard rock. The thrust of this program has been to test and record the performance of fluid hammers in full scale test conditions including, hard formations at simulated depth, high density/high solids drilling muds, and realistic fluid power levels. This paper details the testing and results of testing two 7 3/4 inch diameter mud hammers with 8 1/2 inch hammer bits. A Novatek MHN5 and an SDS Digger FH185 mud hammer were tested with several bit types, with performance being compared to a conventional (IADC Code 537) tricone bit. These tools functionally operated in all of the simulated downhole environments. The performance was in the range of the baseline ticone or better at lower borehole pressures, but at higher borehole pressures the performance was in the lower range or below that of the baseline tricone bit. A new drilling mode was observed, while operating the MHN5 mud hammer. This mode was noticed as the weight on bit (WOB) was in transition from low to high applied load. During this new ''transition drilling mode'', performance was substantially improved and in some cases outperformed the tricone bit. Improvements were noted for the SDS tool while drilling with a more aggressive bit design. Future work includes the optimization of these or the next generation tools for operating in higher density and higher borehole pressure conditions and improving bit design and technology based on the knowledge gained from this test program.

Wadden Sea Mud

DEFF Research Database (Denmark)

Møller-Jensen, P.

The present thesis deals with the transport phenomena of estuarine cohesive sediment from a laboratory and a numerical point of view. The cohesive sediment used throughout the whole process was natural mud from the Danish part of the Wadden sea, Ho Bay. In the laboratory, the work was concentrated...

Treatment and use of muds of wastewaters in the agriculture

International Nuclear Information System (INIS)

Mendez A, Hernando

1995-01-01

The plant includes a preliminary treatment of the domestic residual waters; with two anaerobic reactors type UASB and a facultative lagoon as pos-treatment, system that reaches a removal of 85% of organic load, obtaining a tributary of 20 g/cm 3 of biodegradable oxygen. It is in the primary treatment where muds of interest are generated from the point of view of their application with agricultural and forest aims. These muds present a majors elements as P, Ca, K, Mg and minor, Fe, Cu, Zn being these nutrients and the organic matter the components that allow a good development of the material vegetable forest and agricultural type. In the agricultural area of CORPOICA and the CDMB jointly developed studies of laboratory greenhouse and of field with the purpose of knowing the potential of the muds like nutrition source. The greenhouse study, showed significant results of the muds on the development of the plants of corn and under field conditions the grain production increased from 1.051 kg/ha to 2;077 kg/ha with the treatments without muds and with three tons for hectare respectively. In another study on the pathogen population of muds handling, the behavior of the population of some pathogens organisms, of the blended muds was evaluated with agricultural lime, it diminished the population of fecal coliform bacteria, clastridium, mushrooms and yeasts significantly

Lattice Upgrade Plan for Crab Crossing at the KEKB Rings

CERN Document Server

Morita, Akio; Hosoyama, K; Koiso, Haruyo; Kubo, T; Masuzawa, Mika; Ohmi, Kazuhito; Oide, Katsunobu; Sugahara, Ryuhei; Yoshida, Masato

2005-01-01

We plan to install two superconducting crab cavities into the rings at Janyary, 2006. In our plan, we will install one crab cavity per one ring into the NIKKO straight section where the cryogenic infrastructure is already operated for the superconducting accelerating cavities. In order to obtain the correct crabbing angle at the interaction point(IP), we have to enlarge the horizontal beta function(200m for HER) and have to adjust the horizontal phase advance between the IP and the cavity installation point. In this paper, we will report the lattice modified for the crab crossing and the study results about the single beam dynamics.

The use of artificial crabs for testing predatory behavior and health in the octopus.

Science.gov (United States)

Amodio, Piero; Andrews, Paul; Salemme, Marinella; Ponte, Giovanna; Fiorito, Graziano

2014-01-01

The willingness of the cephalopod mollusc Octopus vulgaris to attack a live crab is traditionally used as a method to assess the overall health and welfare of octopuses in the laboratory. This method requires placing a crab in the home tank of an animal, measuring the time (latency) taken for the octopus to initiate an attack and withdrawing the crab immediately prior to capture. The same crab is commonly used to assess multiple octopuses as part of daily welfare assessment. Growing concern for the welfare of crustaceans and a review of all laboratory practices for the care and welfare of cephalopods following the inclusion of this taxon in 2010/63/EU prompted a study of the utility of an artificial crab to replace a live crab in the assessment of octopus health. On consecutive days O. vulgaris (N=21) were presented with a live, a dead or an artificial crab, and the latency to attack measured. Despite differences in the predatory performance towards the three different crab alternatives, octopuses readily attacked the artificial (and the dead) crab, showing that they can generalize and respond appropriately towards artificial prey. Researchers should consider using an artificial crab to replace the use of a live crab as part of the routine health assessment of O. vulgaris.

Science support for evaluating natural recovery of polychlorinated biphenyl concentrations in fish from Crab Orchard Lake, Crab Orchard National Wildlife Refuge, Illinois

Science.gov (United States)

Kunz, Bethany K.; Hinck, Jo E.; Calfee, Robin D.; Linder, Greg L.; Little, Edward E.

2018-05-11

IntroductionCrab Orchard Lake in southern Illinois is one of the largest and most popular recreational lakes in the state. Construction of the nearly 7,000-acre reservoir in the late 1930s created employment opportunities through the Works Progress Administration, and the lake itself was intended to supply water, control flooding, and provide recreational opportunities for local communities (Stall, 1954). In 1942, the Department of War appropriated or purchased more than 20,000 acres of land around Crab Orchard Lake and constructed the Illinois Ordnance Plant, which manufactured bombs and anti-tank mines during World War II. After the war, an Act of Congress transferred the property to the U.S. Department of the Interior. Crab Orchard National Wildlife Refuge was established on August 5, 1947, for the joint purposes of wildlife conservation, agriculture, recreation, and industry. Production of explosives continued, but new industries also moved onsite. More than 200 tenants have held leases with Crab Orchard National Wildlife Refuge and have operated a variety of manufacturing plants (electrical components, plated metal parts, ink, machined parts, painted products, and boats) on-site. Soils, water, and sediments in several areas of the refuge were contaminated with hazardous substances from handling and disposal methods that are no longer acceptable environmental practice (for example, direct discharge to surface water, use of unlined landfills).Polychlorinated biphenyl (PCB) contamination at the refuge was identified in the 1970s, and a PCB-based fish-consumption advisory has been in effect since 1988 for Crab Orchard Lake. The present advisory covers common carp (Cyprinus carpio) and channel catfish (Ictalurus punctatus); see Illinois Department of Public Health (2017). Some of the most contaminated areas of the refuge were actively remediated, and natural ecosystem recovery processes are expected to further reduce residual PCB concentrations in the lake. The U

Pozzolanic Activity Assessment of LUSI (LUmpur SIdoarjo) Mud in Semi High Volume Pozzolanic Mortar

Science.gov (United States)

Hardjito, Djwantoro; Antoni; Wibowo, Gunadi M.; Christianto, Danny

2012-01-01

LUSI mud obtained from the mud volcano in Sidoarjo, Indonesia, is a viable aluminosilicate material to be utilized as pozzolanic material. LUSI is an abbreviation of the local name of the mud, i.e., Lumpur Sidoarjo, meaning Sidoarjo mud. This paper reports the results of an investigation to assess the pozzolanic activity of LUSI mud, especially in semi high volume pozzolanic mortar. In this case, the amount of mud incorporated is between 30% to 40% of total cementitious material, by mass. The content of SiO2 in the mud is about 30%, whilst the total content of SiO2, Fe2O3 and Al2O3 is more than 70%. Particle size and degree of partial cement replacement by treated LUSI mud affect the compressive strength, the strength activity index (SAI), the rate of pozzolanic activity development, and the workability of mortar incorporating LUSI mud. Manufacturing semi high volume LUSI mud mortar, up to at least 40% cement replacement, is a possibility, especially with a smaller particle size of LUSI mud, less than 63 μm. The use of a larger percentage of cement replacement by LUSI mud does not show any adverse effect on the water demand, as the flow of the fresh mortar increased with the increase of percentage of LUSI mud usage.

Mud Volcanoes of Trinidad as Astrobiological Analogs for Martian Environments

Directory of Open Access Journals (Sweden)

Riad Hosein

2014-10-01

Full Text Available Eleven onshore mud volcanoes in the southern region of Trinidad have been studied as analog habitats for possible microbial life on Mars. The profiles of the 11 mud volcanoes are presented in terms of their physical, chemical, mineralogical, and soil properties. The mud volcanoes sampled all emitted methane gas consistently at 3% volume. The average pH for the mud volcanic soil was 7.98. The average Cation Exchange Capacity (CEC was found to be 2.16 kg/mol, and the average Percentage Water Content was 34.5%. Samples from three of the volcanoes, (i Digity; (ii Piparo and (iii Devil’s Woodyard were used to culture bacterial colonies under anaerobic conditions indicating possible presence of methanogenic microorganisms. The Trinidad mud volcanoes can serve as analogs for the Martian environment due to similar geological features found extensively on Mars in Acidalia Planitia and the Arabia Terra region.

Mud Volcanoes of Trinidad as Astrobiological Analogs for Martian Environments

Science.gov (United States)

Hosein, Riad; Haque, Shirin; Beckles, Denise M.

2014-01-01

Eleven onshore mud volcanoes in the southern region of Trinidad have been studied as analog habitats for possible microbial life on Mars. The profiles of the 11 mud volcanoes are presented in terms of their physical, chemical, mineralogical, and soil properties. The mud volcanoes sampled all emitted methane gas consistently at 3% volume. The average pH for the mud volcanic soil was 7.98. The average Cation Exchange Capacity (CEC) was found to be 2.16 kg/mol, and the average Percentage Water Content was 34.5%. Samples from three of the volcanoes, (i) Digity; (ii) Piparo and (iii) Devil’s Woodyard were used to culture bacterial colonies under anaerobic conditions indicating possible presence of methanogenic microorganisms. The Trinidad mud volcanoes can serve as analogs for the Martian environment due to similar geological features found extensively on Mars in Acidalia Planitia and the Arabia Terra region. PMID:25370529

Use of red mud as addition for portland cement mortars

International Nuclear Information System (INIS)

Ribeiro, D.V.; Morelli, M.R.

2011-01-01

The aim of the present research work was to investigate the possibility of adding red mud, an alkaline leaching waste that is obtained from bauxite during the Bayer process for alumina production, in the raw meal of Portland cement mortars. The red mud is classified as dangerous, according to NBR 10004/2004, and world while generation reached over 117 million tons/year. This huge production requires high consuming products to be used as incorporation matrix and we studied the influence of red mud addition on the characteristics of cement mortars and concrete. In this paper the properties of Portland cement mortars incorporating high amounts of red mud was evaluated: pH variation, fresh (setting time, workability or normal consistency and water retention), and hardened state (mechanical strength, capillary water absorption, density and apparent porosity). Results seem promising for red mud additions up to 20 wt%. (author)

Mud volcanoes of trinidad as astrobiological analogs for martian environments.

Science.gov (United States)

Hosein, Riad; Haque, Shirin; Beckles, Denise M

2014-10-13

Eleven onshore mud volcanoes in the southern region of Trinidad have been studied as analog habitats for possible microbial life on Mars. The profiles of the 11 mud volcanoes are presented in terms of their physical, chemical, mineralogical, and soil properties. The mud volcanoes sampled all emitted methane gas consistently at 3% volume. The average pH for the mud volcanic soil was 7.98. The average Cation Exchange Capacity (CEC) was found to be 2.16 kg/mol, and the average Percentage Water Content was 34.5%. Samples from three of the volcanoes, (i) Digity; (ii) Piparo and (iii) Devil's Woodyard were used to culture bacterial colonies under anaerobic conditions indicating possible presence of methanogenic microorganisms. The Trinidad mud volcanoes can serve as analogs for the Martian environment due to similar geological features found extensively on Mars in Acidalia Planitia and the Arabia Terra region.

M10.3.4: CLIC crab cavity specifications completed

CERN Document Server

Dexter, A; Ambattu, P; Shinton, I; Jones, R

2010-01-01

The starting point of Sub-task 2 is to document the currently anticipated requirements for the CLIC crab cavity system. This milestone concerns completion of the basic specifications for the CLIC crab cavity system. This comprises kick, power requirement, phase and amplitude stability, technology choice, and RF layout. The wakefield calculations of a baseline CLIC cavity will be used to estimate the required damping of the higher order modes as well as other special modes in crab cavities (the lower and same order modes).

CLIC CRAB CAVITY SPECIFICATIONS MILESTONE: M10.3.4

CERN Document Server

Ambattu, P; Dexter, A; Jones, R; McIntosh, P; Shinton, I

2010-01-01

The starting point of Sub-task 2 is to document the currently anticipated requirements for the CLIC crab cavity system. This milestone concerns completion of the basic specifications for the CLIC crab cavity system. This comprises kick, power requirement, phase and amplitude stability, technology choice, and RF layout. The wakefield calculations of a baseline CLIC cavity will be used to estimate the required damping of the higher order modes as well as other special modes in crab cavities (the lower and same order modes).

Eruption of a deep-sea mud volcano triggers rapid sediment movement

Science.gov (United States)

Feseker, Tomas; Boetius, Antje; Wenzhöfer, Frank; Blandin, Jerome; Olu, Karine; Yoerger, Dana R.; Camilli, Richard; German, Christopher R.; de Beer, Dirk

2014-01-01

Submarine mud volcanoes are important sources of methane to the water column. However, the temporal variability of their mud and methane emissions is unknown. Methane emissions were previously proposed to result from a dynamic equilibrium between upward migration and consumption at the seabed by methane-consuming microbes. Here we show non-steady-state situations of vigorous mud movement that are revealed through variations in fluid flow, seabed temperature and seafloor bathymetry. Time series data for pressure, temperature, pH and seafloor photography were collected over 431 days using a benthic observatory at the active Håkon Mosby Mud Volcano. We documented 25 pulses of hot subsurface fluids, accompanied by eruptions that changed the landscape of the mud volcano. Four major events triggered rapid sediment uplift of more than a metre in height, substantial lateral flow of muds at average velocities of 0.4 m per day, and significant emissions of methane and CO2 from the seafloor. PMID:25384354

Laboratory exposures of invertebrate and vertebrate species to concentrations of IA-35 (Petro-Canada) drill mud fluid, production water, and Hibernia mud cuttings

Energy Technology Data Exchange (ETDEWEB)

Payne, J.; Fancey, L.; Andrews, C.; Meade, J.; Power, F.; Veinot, G. [Department of Fisheries and Oceans, St. John' s, NF (Canada). Science Branch; Lee, K. [Department of Fisheries and Oceans, Mont-Joli, PQ (Canada). Maurice Lamontagne Inst.; Cook, A. [Environment Canada, Moncton, NB (Canada). Environmental Quality Laboratory

2001-04-01

The authors studied the short term effects on brine shrimp nauplii (Artemia franciscana), capelin larvae (Mallotus villosus), marine copepods (Calanus finmarchicus), juvenile yellowtail flounder (Limanda ferruginea) and ctenophores (Pleurobrachius pileus) of synthetic drill mud fluid, produced water and drill mud cuttings. In this report, they presented the data collected, including data on the water solubility of Petro-Canada drill mud fluid IA-35 and metal analysis of production water from the Sable Island Offshore Exploration Project. Low acute toxicity potential for drill mud fluid, production water and Hibernia drill cuttings for the species and life stages tested were revealed. The hypothesis to the effect that wastes pose very little or no risk of an acute toxic nature to the marine environment were reinforced by the results from this study. 5 refs., 25 tabs.

GROWTH PERFORMANCE AND MEAT QUALITY OF DOMESTICATED BLUE SWIMMING CRAB (Portunus pelagicus)

OpenAIRE

Fujaya, Yushinta; Trijuno, Dody Dharmawan; Aslamyah, Siti; Alam, Nur

2015-01-01

Blue Swimming Crab (Portunus pelagicus) is one of the commercial crabs traded widely around the world. But, crab aquaculture has not made a significant contribution in meeting the increasing overseas market demand. Some constraints in crab cultivation were high mortality, low and variable growth rate, and low of meat quality. The aims of this research were to produce a superior broodstock through domestication and selective breeding. Superior broodstock was expected to produce a high qual...

Linking geochemical processes in mud volcanoes with arsenic mobilization driven by organic matter

Energy Technology Data Exchange (ETDEWEB)

Liu, Chia-Chuan; Kar, Sandeep [Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan (China); Jean, Jiin-Shuh, E-mail: jiinshuh@mail.ncku.edu.tw [Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan (China); Wang, Chung-Ho [Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan (China); Lee, Yao-Chang [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China); Sracek, Ondra [OPV s.r.o. (Groundwater Protection Ltd.), Bělohorská 31, 169 00 Praha 6 (Czech Republic); Department of Geology, Faculty of Science, Palacký University, 17. listopadu 12, 771 46 Olomouc (Czech Republic); Li, Zhaohui [Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan (China); Department of Geosciences, University of Wisconsin – Parkside, Kenosha, WI 53144 (United States); Bundschuh, Jochen [Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan (China); Faculty of Engineering and Surveying and National Centre for Engineering in Agriculture, The University of Southern Queensland, Toowoomba (Australia); Yang, Huai-Jen [Department of Earth Sciences, National Cheng Kung University, Tainan, Taiwan (China); Chen, Chien-Yen [Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi 621, Taiwan (China)

2013-11-15

Highlights: ► Study represents geochemical characteristics and their spatial variability among six mud volcanoes of southern Taiwan. ► Anoxic mud volcanic fluids containing high NaCl imply connate water as the possible source. ► δ{sup 18}O-rich fluids is associated with silicate and carbonate mineral released through water–rock interaction. ► High As content in mud and its sequential extraction showed mostly adsorbed As on organic and sulphidic phases. ► Organic matter specially humic acid showed redox dependence and it may play an important role in binding and mobility of arsenic. -- Abstract: The present study deals with geochemical characterization of mud fluids and sediments collected from Kunshuiping (KSP), Liyushan (LYS), Wushanting (WST), Sinyangnyuhu (SYNH), Hsiaokunshui (HKS) and Yenshuikeng (YSK) mud volcanoes in southwestern Taiwan. Chemical constituents (cations, anions, trace elements, organic carbon, humic acid, and stable isotopes) in both fluids and mud were analyzed to investigate the geochemical processes and spatial variability among the mud volcanoes under consideration. Analytical results suggested that the anoxic mud volcanic fluids are highly saline, implying connate water as the probable source. The isotopic signature indicated that δ{sup 18}O-rich fluids may be associated with silicate and carbonate mineral released through water–rock interaction, along with dehydration of clay minerals. Considerable amounts of arsenic in mud irrespective of fluid composition suggested possible release through biogeochemical processes in the subsurface environment. Sequential extraction of As from the mud indicated that As was mostly present in organic and sulphidic phases, and adsorbed on amorphous Mn oxyhydroxides. Volcanic mud and fluids are rich in organic matter (in terms of organic carbon), and the presence of humic acid in mud has implications for the binding of arsenic. Functional groups of humic acid also showed variable sources of

Linking geochemical processes in mud volcanoes with arsenic mobilization driven by organic matter.

Science.gov (United States)

Liu, Chia-Chuan; Kar, Sandeep; Jean, Jiin-Shuh; Wang, Chung-Ho; Lee, Yao-Chang; Sracek, Ondra; Li, Zhaohui; Bundschuh, Jochen; Yang, Huai-Jen; Chen, Chien-Yen

2013-11-15

The present study deals with geochemical characterization of mud fluids and sediments collected from Kunshuiping (KSP), Liyushan (LYS), Wushanting (WST), Sinyangnyuhu (SYNH), Hsiaokunshui (HKS) and Yenshuikeng (YSK) mud volcanoes in southwestern Taiwan. Chemical constituents (cations, anions, trace elements, organic carbon, humic acid, and stable isotopes) in both fluids and mud were analyzed to investigate the geochemical processes and spatial variability among the mud volcanoes under consideration. Analytical results suggested that the anoxic mud volcanic fluids are highly saline, implying connate water as the probable source. The isotopic signature indicated that δ(18)O-rich fluids may be associated with silicate and carbonate mineral released through water-rock interaction, along with dehydration of clay minerals. Considerable amounts of arsenic in mud irrespective of fluid composition suggested possible release through biogeochemical processes in the subsurface environment. Sequential extraction of As from the mud indicated that As was mostly present in organic and sulphidic phases, and adsorbed on amorphous Mn oxyhydroxides. Volcanic mud and fluids are rich in organic matter (in terms of organic carbon), and the presence of humic acid in mud has implications for the binding of arsenic. Functional groups of humic acid also showed variable sources of organic matter among the mud volcanoes being examined. Because arsenate concentration in the mud fluids was found to be independent from geochemical factors, it was considered that organic matter may induce arsenic mobilization through an adsorption/desorption mechanism with humic substances under reducing conditions. Organic matter therefore plays a significant role in the mobility of arsenic in mud volcanoes. Copyright © 2012 Elsevier B.V. All rights reserved.

Durability of Bricks Coated with Red mud Based Geopolymer Paste

Science.gov (United States)

Singh, Smita; Basavanagowda, S. N.; Aswath, M. U.; Ranganath, R. V.

2016-09-01

The present study is undertaken to assess the durability of concrete blocks coated with red mud - fly ash based geopolymer paste. Concrete blocks of size 200 x 200 x 100mm were coated with geopolymer paste synthesized by varying the percentages of red mud and fly ash. Uncoated concrete blocks were also tested for the durability for comparison. In thermal resistance test, the blocks were subjected to 600°C for an hour whereas in acid resistance test, they were kept in 5% sulphuric acid solution for 4 weeks. The specimens were thereafter studied for surface degradation, strength loss and weight loss. Pastes with red mud percentage greater than 50% developed lot of shrinkage cracks. The blocks coated with 30% and 50% red mud paste showed better durability than the other blocks. The use of blocks coated with red mud - fly ash geopolymer paste improves the aesthetics, eliminates the use of plaster and improves the durability of the structure.

Gender and snow crab occupational asthma in Newfoundland and Labrador, Canada

International Nuclear Information System (INIS)

Howse, Dana; Gautrin, Denyse; Neis, Barbara; Cartier, Andre; Horth-Susin, Lise; Jong, Michael; Swanson, Mark C.

2006-01-01

Fish and shellfish processing employs many thousands of people globally, with shellfish processing becoming more important in recent years. Shellfish processing is associated with multiple occupational health and safety (OHS) risks. Snow crab occupational asthma (OA) is work-related asthma associated with processing snow crab. We present a gender analysis of findings from a 3-year multifaceted study of snow crab OA in Newfoundland and Labrador, Canada. The study was carried out in four snow crab processing communities between 2001 and 2004. An anonymous survey questionnaire on knowledge, beliefs, and concerns related to processing snow crab administered to 158 workers attending community meetings at the start of the research found that women were significantly more likely than men to associate certain health problems, especially chest tightness, difficulty breathing, and cough, with crab processing (P<0.001). Worker health assessments carried out with 215 processing workers (187 current/28 former; 120 female/95 male) found that female participants were more likely to be diagnosed as almost certain/highly probable snow crab OA and allergy (P=0.001) and to be sensitized to snow crab (P=0.01) than male participants. Work histories from the health assessments were used to classify processing jobs as male or female. Allergen sampling (211 allergen samples: 115 area, 96 personal breathing zone) indicated that the plant areas where these male jobs were concentrated were associated with lower levels of aerosolized crab allergens (the agents responsible for OA to snow crab) than areas associated with female jobs. This difference was statistically significant in the two plants with poor ventilation (p<0.001 and P=0.017 for these plants). A gender analysis of work history data showed that female health assessment participants were likely to have worked longer processing snow crab than males (5 years versus 3.5 years, respectively). Cross-referencing of work history results

Evolutionary history of true crabs (Crustacea: Decapoda: Brachyura) and the origin of freshwater crabs.

Science.gov (United States)

Tsang, Ling Ming; Schubart, Christoph D; Ahyong, Shane T; Lai, Joelle C Y; Au, Eugene Y C; Chan, Tin-Yam; Ng, Peter K L; Chu, Ka Hou

2014-05-01

Crabs of the infra-order Brachyura are one of the most diverse groups of crustaceans with approximately 7,000 described species in 98 families, occurring in marine, freshwater, and terrestrial habitats. The relationships among the brachyuran families are poorly understood due to the high morphological complexity of the group. Here, we reconstruct the most comprehensive phylogeny of Brachyura to date using sequence data of six nuclear protein-coding genes and two mitochondrial rRNA genes from more than 140 species belonging to 58 families. The gene tree confirms that the "Podotremata," are paraphyletic. Within the monophyletic Eubrachyura, the reciprocal monophyly of the two subsections, Heterotremata and Thoracotremata, is supported. Monophyly of many superfamilies, however, is not recovered, indicating the prevalence of morphological convergence and the need for further taxonomic studies. Freshwater crabs were derived early in the evolution of Eubrachyura and are shown to have at least two independent origins. Bayesian relaxed molecular methods estimate that freshwater crabs separated from their closest marine sister taxa ~135 Ma, that is, after the break up of Pangaea (∼200 Ma) and that a Gondwanan origin of these freshwater representatives is untenable. Most extant families and superfamilies arose during the late Cretaceous and early Tertiary.

Heavy metals in red crabs, Chaceon quinquedens, from the Gulf of Mexico.

Science.gov (United States)

Perry, Harriet; Isphording, Wayne; Trigg, Christine; Riedel, Ralf

2015-12-30

The red crab, Chaceon quinquedens, is distributed in deep waters of the Gulf of Mexico (GOM) and is most abundant in an area associated with sediment deposition from the Mississippi River. Sediment geochemistry and biological and ecological traits of red crabs favor accumulation of contaminants. Red crabs, sediment, and bottom water samples were taken from three distinct geographic locations representing areas with differing exposure to contaminant laden effluents from the Mississippi River. Inductively coupled plasma spectrophotometry and atomic absorption spectrophotometry were employed to determine levels of heavy metals in red crab muscle tissue. Ion site partitioning was used to determine metal speciation in sediments. Red crabs showed evidence of heavy metal bioaccumulation in all sample areas with high variability in contaminant levels in individual crabs for some metals. Bioavailability of metals in sediment did not always result in accumulation in muscle tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

Associational resistance protects mangrove leaves from crab herbivory

Science.gov (United States)

Erickson, Amy A.; Bell, Susan S.; Dawes, Clinton J.

2012-05-01

While associational defenses have been well documented in many plant and algal ecosystems, this study is the first to document associational resistance in mangroves. Mangrove tree crab (Aratus pisonii) density and herbivory on three life-stages of the red mangrove (Rhizophora mangle) were documented in pure red versus mixed-species and predominantly non-red mangrove stands containing black (Avicennia germinans) and white (Laguncularia racemosa) mangroves in 1999-2000 in Tampa Bay, Florida. This study first established that R. mangle is the focal species in the context of associational resistance because it is damaged more than either of the other mangrove species. Next, it was hypothesized that crab density and leaf damage on R. mangle would be lower when in mixed-species and predominantly non-red versus red mangrove stands. A non-significant trend suggested that crab density varies among stands, and crab damage on R. mangle leaves was significantly lower in mixed-species and non-red stands. Mechanisms to explain associational resistance were examined. Positive Pearson correlations between the percent of adult R. mangle in a stand and both crab density and R. mangle leaf damage provided support for the resource concentration hypothesis. Limited support was found for the attractant-decoy hypothesis because the total amount of damaged leaves of all mangrove species combined typically differed among stands, suggesting that crabs were not shifting to alternative mangrove species to offset reduced availability of R. mangle leaves. Finally, while R. mangle seedlings were shorter in non-red stands compared to others, intra-specific differences in R. mangle leaf chemistry and sclerophylly among stands failed to explain associational patterns. These combined results argue for the need for additional experiments to elucidate mechanisms responsible for defensive plant associations in mangrove ecosystems and to determine whether such associations could be of use in mangrove

Comparison with Offshore and Onshore Mud Volcanoes in the Southwestern Taiwan

Science.gov (United States)

Chen, Y. H.; Su, C. C.; Chen, T. T.; Liu, C. S.; Paull, C. K.; Caress, D. W.; Gwiazda, R.; Lundsten, E. M.; Hsu, H. H.

2017-12-01

The offshore area southwest (SW) of Taiwan is on the convergent boundary between the Eurasian and Philippine Sea plates. The plate convergence manifests in this unique geological setting as a fold-and-thrust-belt. Multi-channel seismic profiles, and bathymetry and gravity anomaly data collected from Taiwan offshore to the SW show the presence of a large amount of mud volcanoes and diapirs with NE-SW orientations. In the absence of comprehensive sampling and detailed geochemistry data from submarine mud volcanoes, the relation between onshore and offshore mud volcanoes remains ambiguous. During two MBARI and IONTU joint cruises conducted in 2017 we collected high-resolution multibeam bathymetry data (1-m-resolution) and chirp sub-bottom profiles with an autonomous underwater vehicle (AUV) from submarine Mud Volcano III (MV3), and obtained precisely located samples and video observations with a remotely operated vehicle (ROV). MV3 is an active submarine mud volcano at 465 m water depth offshore SW Taiwan. This cone-shape mud volcano is almost 780 m wide, 150 m high, with 8° slopes, and a 30 m wide mound on the top. Several linear features are observed in the southwest of the mound, and these features are interpreted as a series of marks caused by rolling rocks that erupted from the top of MV3. We collected three rocks and push cores from MV3 and its top with the ROV, in order to compare their chemical and mineralogical composition to that of samples collected from mud volcanoes along the Chishan fault. The surface and X-radiography imaging, 210Pb chronology, grain size and X-ray diffractometer analyses were conducted to compare geochemical and sedimentary properties of offshore and onshore mud volcanoes. The results indicate that the offshore and onshore mud volcanoes have similar characteristics. We suggest that offshore and onshore mud volcanoes of SW Taiwan are no different in the source of their materials and their mechanism of creation and evolution.

A geochemical study on mud volcanoes in the Junggar Basin, China

Energy Technology Data Exchange (ETDEWEB)

Nakada, Ryoichi, E-mail: ryo-nakada@hiroshima-u.ac.jp [Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Takahashi, Yoshio [Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Tsunogai, Urumu [Division of Earth and Planetary Sciences, Graduate School of Science, Hokkaido University, Kita-10 Nishi-8, Kita-ku, Sapporo 060-0810 (Japan); Zheng Guodong [Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, 382 West Donggang Road, Lanzhou 730000 (China); Shimizu, Hiroshi [Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Hattori, Keiko H. [Department of Earth Science, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada)

2011-07-15

Highlights: > Gases released from Xinjiang mud volcanoes are dominated by thermogenic origin. > Secondary microbial activities occurring closer to the surface dramatically changed the {delta}{sup 13}C{sub CO2}. > The water-rock interaction occurred at deeper level than gas and petroleum reservoir. - Abstract: A comprehensive study was performed to characterize, for the first time, the mud, water, and gases released from onshore mud volcanoes located in the southern margin of the Junggar Basin, northwestern China. Chemical compositions of mud, along with the geology of the basin, suggest that a source of the mud is Mesozoic or Cenozoic shale. Oxygen and H isotope compositions of the released water suggest a local meteoric origin. Combined with the positive Eu anomalies of the water, a large {sup 18}O shift of the water suggests extensive interaction with rocks. Gases discharged from the mud volcanoes are predominantly thermogenic hydrocarbons, and the high {delta}{sup 13}C values (>+20 per mille VPDB) for CO{sub 2} gases and dissolved carbonate in muddy water suggest secondary methanogenesis with CO{sub 2} reduction after oil biodegradation. The enrichments of Eu and {sup 18}O in water and the low thermal gradient of the area suggest that the water-rock interactions possibly occur deeper than 3670 {+-} 200 m. On the other hand, considering the relationship to the petroleum reservoir around the mud volcanoes, the depth of the gases can be derived from about 3600 m, a depth that is greater than that generally estimated for reservoirs whose gas is characterized by {sup 13}C-enriched CO{sub 2}. Oil biodegradation with CO{sub 2} reduction likely occurs at a shallower depth along the seepage system of the mud volcano. The results contribute to the worldwide data set of gas genesis in mud volcanoes. Moreover, they further support the concept that most terrestrial mud volcanoes release thermogenic gas produced in very deep sediments and may be early indicators of oil

Corneal laceration caused by river crab

Directory of Open Access Journals (Sweden)

Vinuthinee N

2015-01-01

Full Text Available Naidu Vinuthinee,1,2 Anuar Azreen-Redzal,1 Jaafar Juanarita,1 Embong Zunaina2 1Department of Ophthalmology, Hospital Sultanah Bahiyah, Alor Setar, 2Department of Ophthalmology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia Abstract: A 5-year-old boy presented with right eye pain associated with tearing and photophobia of 1-day duration. He gave a history of playing with a river crab when suddenly the crab clamped his fingers. He attempted to fling the crab off, but the crab flew and hit his right eye. Ocular examination revealed a right eye corneal ulcer with clumps of fibrin located beneath the corneal ulcer and 1.6 mm level of hypopyon. At presentation, the Seidel test was negative, with a deep anterior chamber. Culture from the corneal scrapping specimen grew Citrobacter diversus and Proteus vulgaris, and the boy was treated with topical gentamicin and ceftazidime eyedrops. Fibrin clumps beneath the corneal ulcer subsequently dislodged, and revealed a full-thickness corneal laceration wound with a positive Seidel test and shallow anterior chamber. The patient underwent emergency corneal toileting and suturing. Postoperatively, he was treated with oral ciprofloxacin 250 mg 12-hourly for 1 week, topical gentamicin, ceftazidime, and dexamethasone eyedrops for 4 weeks. Right eye vision improved to 6/9 and 6/6 with pinhole at the 2-week follow-up following corneal suture removal. Keywords: corneal ulcer, pediatric trauma, ocular injury

OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE - A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING

Energy Technology Data Exchange (ETDEWEB)

Arnis Judzis

2003-01-01

This document details the progress to date on the ''OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE -- A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING'' contract for the quarter starting October 2002 through December 2002. Even though we are awaiting the optimization portion of the testing program, accomplishments included the following: (1) Smith International participated in the DOE Mud Hammer program through full scale benchmarking testing during the week of 4 November 2003. (2) TerraTek acknowledges Smith International, BP America, PDVSA, and ConocoPhillips for cost-sharing the Smith benchmarking tests allowing extension of the contract to add to the benchmarking testing program. (3) Following the benchmark testing of the Smith International hammer, representatives from DOE/NETL, TerraTek, Smith International and PDVSA met at TerraTek in Salt Lake City to review observations, performance and views on the optimization step for 2003. (4) The December 2002 issue of Journal of Petroleum Technology (Society of Petroleum Engineers) highlighted the DOE fluid hammer testing program and reviewed last years paper on the benchmark performance of the SDS Digger and Novatek hammers. (5) TerraTek's Sid Green presented a technical review for DOE/NETL personnel in Morgantown on ''Impact Rock Breakage'' and its importance on improving fluid hammer performance. Much discussion has taken place on the issues surrounding mud hammer performance at depth conditions.

Advanced Mud System for Microhole Coiled Tubing Drilling

Energy Technology Data Exchange (ETDEWEB)

Kenneth Oglesby

2008-12-01

An advanced mud system was designed and key components were built that augment a coiled tubing drilling (CTD) rig that is designed specifically to drill microholes (less than 4-inch diameter) with advanced drilling techniques. The mud system was tailored to the hydraulics of the hole geometries and rig characteristics required for microholes and is capable of mixing and circulating mud and removing solids while being self contained and having zero discharge capability. Key components of this system are two modified triplex mud pumps (High Pressure Slurry Pumps) for advanced Abrasive Slurry Jetting (ASJ) and a modified Gas-Liquid-Solid (GLS) Separator for well control, flow return and initial processing. The system developed also includes an additional component of an advanced version of ASJ which allows cutting through most all materials encountered in oil and gas wells including steel, cement, and all rock types. It includes new fluids and new ASJ nozzles. The jetting mechanism does not require rotation of the bottom hole assembly or drill string, which is essential for use with Coiled Tubing (CT). It also has low reactive forces acting on the CT and generates cuttings small enough to be easily cleaned from the well bore, which is important in horizontal drilling. These cutting and mud processing components and capabilities compliment the concepts put forth by DOE for microhole coiled tubing drilling (MHTCTD) and should help insure the reality of drilling small diameter holes quickly and inexpensively with a minimal environmental footprint and that is efficient, compact and portable. Other components (site liners, sump and transfer pumps, stacked shakers, filter membranes, etc.. ) of the overall mud system were identified as readily available in industry and will not be purchased until we are ready to drill a specific well.

Red mud flocculation process in alumina production

Science.gov (United States)

Fedorova, E. R.; Firsov, A. Yu

2018-05-01

The process of thickening and washing red mud is a gooseneck of alumina production. The existing automated systems of the thickening process control involve stabilizing the parameters of the primary technological circuits of the thickener. The actual direction of scientific research is the creation and improvement of models and systems of the thickening process control by model. But the known models do not fully consider the presence of perturbing effects, in particular the particle size distribution in the feed process, distribution of floccules by size after the aggregation process in the feed barrel. The article is devoted to the basic concepts and terms used in writing the population balance algorithm. The population balance model is implemented in the MatLab environment. The result of the simulation is the particle size distribution after the flocculation process. This model allows one to foreseen the distribution range of floccules after the process of aggregation of red mud in the feed barrel. The mud of Jamaican bauxite was acting as an industrial sample of red mud; Cytec Industries of HX-3000 series with a concentration of 0.5% was acting as a flocculant. When simulating, model constants obtained in a tubular tank in the laboratories of CSIRO (Australia) were used.

Effect of potassium-salt muds on gamma ray, and spontaneous potential measurements

International Nuclear Information System (INIS)

Cox, J.W.; Raymer, L.L.

1976-01-01

Interpretations of the gamma ray and Spontaneous Potential curves generally assume the presence of sodium chloride as the dominant salt in both the formation water and the mud filtrate. However, potassium-salt muds are increasingly being used by the oil industry. The potassium cation is significantly different from the sodium cation in its radioactive and electrochemical properties. Natural potassium contains a radioactive isotope which emits gamma rays. Thus, the presence of potassium salts in the mud system may contribute to Gamma-Ray tool response. Since the Gamma Ray is used quantitatively in many geological sequences as an indicator of clay content, a way to correct for the effect of potassium in the mud column is desirable. Correction methods and charts based on laboratory measurements and field observations are presented. The effect of temperature on the resistivity of potassium muds is also briefly discussed. From data available, it appears to be similar to that for NaCl muds. On the bases of field observations and laboratory work, the electrochemical properties of potassium-chloride and potassium-carbonate muds and mud filtrates are discussed. Activity relationships are proposed, and the influence of these salts on the SP component potentials--namely, the liquid-junction, membrane, and bi-ionic potentials--is described. Several field examples are presented

Biological properties of mud extracts derived from various spa resorts.

Science.gov (United States)

Spilioti, Eliana; Vargiami, Margarita; Letsiou, Sophia; Gardikis, Konstantinos; Sygouni, Varvara; Koutsoukos, Petros; Chinou, Ioanna; Kassi, Eva; Moutsatsou, Paraskevi

2017-08-01

Spa resorts are known for thousands of years for their healing properties and have been empirically used for the treatment of many inflammatory conditions. Mud is one of the most often used natural materials for preventive, healing and cosmetic reasons and although it has been used since the antiquity, little light has been shed on its physical, chemical and biological properties. In this study we examined the effect of mud extracts on the expression of adhesion molecules (CAMs) by endothelial cells as well as their effects on monocyte adhesion to activated endothelial cells. Most of mud extracts inhibited the expression of VCAM-1 by endothelial cells and reduced monocyte adhesion to activated endothelial cells, indicating a potent anti-inflammatory activity. Furthermore, the mud extracts were tested for their antimicrobial activity; however, most of them appeared inactive against S. aureus and S. epidermidis. One of the mud extracts (showing the best stabilization features) increased significantly the expression of genes involved in cell protection, longevity and hydration of human keratinocytes, such as, collagen 6A1, forkhead box O3, sirtuin-1, superoxide dismutase 1 and aquaporin-3. The present study reveals that mud exerts important beneficial effects including anti-inflammatory and anti-aging activity as well as moisturizing effects, implicating important cosmeceutical applications.

Valorisation of waste ilmenite mud in the manufacture of sulphur polymer cement.

Science.gov (United States)

Contreras, Manuel; Gázquez, Manuel Jesús; García-Díaz, Irene; Alguacil, Francisco J; López, Félix A; Bolívar, Juan Pedro

2013-10-15

This paper reports the preparation of sulphur polymer cements (SPCs) incorporating waste ilmenite mud for use in concrete construction works. The ilmenite mud raw material and the mud-containing SPCs (IMC-SPCs) were characterised physico-chemically and radiologically. The optimal IMC-SPC mixture had a sulphur/mud ratio (w/w) of 1.05 (mud dose 20 wt%); this cement showed the greatest compressive strength (64 MPa) and the lowest water absorption coefficient (0.4 g cm(-2) at 28 days). Since ilmenite mud is enriched in natural radionuclides, such as radium isotopes (2.0·10(3) Bq kg(-1)(228)Ra and 5.0·10(2) Bq kg(-1)(226)Ra), the IMC-SPCs were subjected to leaching experiments, which showed their environmental impact to be negligible. The activity concentration indices for the different radionuclides in the IMC-SPCs containing 10% and 20% ilmenite mud met the demands of international standards for materials used in the construction of non-residential buildings. Copyright © 2013 Elsevier Ltd. All rights reserved.

Invasive Crabs in the Barents Sea

DEFF Research Database (Denmark)

Kaiser, Brooks; Fernandez, Linda; Kourantidou, Melina

The recent invasions of the red king crab (RKC) and the snow crab (SC) in the Barents Sea represent the sorts of integrated ecological and economic shifts we may expect as climate change affects arctic seas. Economic incentives and ecological unknowns have combined to change the current...... and potentially future productivity and profitability of the Barents ecosystem in complex and interacting ways. We examine potential ecological-economic trajectories for these crabs’ continued expansions in the Arctic and how the profitability, the joint and national management structures in Norway and Russia...

Mud Volcanoes - Analogs to Martian Cones and Domes (by the Thousands!)

Science.gov (United States)

Allen, Carlton C.; Oehler, Dorothy

2010-01-01

Mud volcanoes are mounds formed by low temperature slurries of gas, liquid, sediments and rock that erupt to the surface from depths of meters to kilometers. They are common on Earth, with estimates of thousands onshore and tens of thousands offshore. Mud volcanoes occur in basins with rapidly-deposited accumulations of fine-grained sediments. Such settings are ideal for concentration and preservation of organic materials, and mud volcanoes typically occur in sedimentary basins that are rich in organic biosignatures. Domes and cones, cited as possible mud volcanoes by previous authors, are common on the northern plains of Mars. Our analysis of selected regions in southern Acidalia Planitia has revealed over 18,000 such features, and we estimate that more than 40,000 occur across the area. These domes and cones strongly resemble terrestrial mud volcanoes in size, shape, morphology, associated flow structures and geologic setting. Geologic and mineralogic arguments rule out alternative formation mechanisms involving lava, ice and impacts. We are studying terrestrial mud volcanoes from onshore and submarine locations. The largest concentration of onshore features is in Azerbaijan, near the western edge of the Caspian Sea. These features are typically hundreds of meters to several kilometers in diameter, and tens to hundreds of meters in height. Satellite images show spatial densities of 20 to 40 eruptive centers per 1000 square km. Many of the features remain active, and fresh mud flows as long as several kilometers are common. A large field of submarine mud volcanoes is located in the Gulf of Cadiz, off the Atlantic coasts of Morocco and Spain. High-resolution sonar bathymetry reveals numerous km-scale mud volcanoes, hundreds of meters in height. Seismic profiles demonstrate that the mud erupts from depths of several hundred meters. These submarine mud volcanoes are the closest morphologic analogs yet found to the features in Acidalia Planitia. We are also conducting

Beyond the CRAB symptoms: a study of presenting clinical manifestations of multiple myeloma.

Science.gov (United States)

Talamo, Giampaolo; Farooq, Umar; Zangari, Maurizio; Liao, Jason; Dolloff, Nathan G; Loughran, Thomas P; Epner, Elliot

2010-12-01

Although the typical clinical manifestations of multiple myeloma (MM) are summarized by the CRAB symptoms (hypercalcemia, renal insufficiency, anemia, and bone lesions), a significant proportion of patients with MM present with a variety of other clinical manifestations. We conducted a study evaluating the presenting symptoms that led to the diagnosis of MM. We conducted a retrospective review of 170 consecutive patients with MM seen at the Penn State Hershey Cancer Institute. Among patients with symptomatic MM, 74% presented with CRAB symptoms, 20% presented with non-CRAB manifestations, and 6% had both clinical features. Ten categories of non-CRAB manifestations were found, in order of decreasing frequency: neuropathy (because of spinal cord compression, nerve root compression, or peripheral neuropathy), extramedullary involvement, hyperviscosity syndrome, concomitant amyloidosis (eg, nephrotic syndrome or cardiopathy), hemorrhage/coagulopathy, systemic symptoms (eg, fever or weight loss), primary plasma cell leukemia, infections, cryoglobulinemia, and secondary gout. Kaplan-Meier estimates of survival in patients with non-CRAB manifestations did not show a significant difference from the survival of patients presenting with CRAB symptoms. Presenting symptoms of MM may be grouped in a total of 14 categories, 4 for the CRAB and 10 for the less common non-CRAB features. Grouped together, non-CRAB manifestations do not appear to confer a negative effect on the prognosis of patients with MM.

Crab Cavities: Past, Present, and Future of a Challenging Device

OpenAIRE

Wu, Q

2015-01-01

In two-ring facilities operating with a crossing-angle collision scheme, luminosity can be limited due to an incomplete overlapping of the colliding bunches. Crab cavities then are introduced to restore head-on collisions by providing the destined opposite deflection to the head and tail of the bunch. An increase in luminosity was demonstrated at KEKB with global crab- crossing, while the Large Hardron Collider (LHC) at CERN currently is designing local crab crossing for the Hi-Lumi upgrade. ...

Isoform-specific functions of Mud/NuMA mediate binucleation of Drosophila male accessory gland cells.

Science.gov (United States)

Taniguchi, Kiichiro; Kokuryo, Akihiko; Imano, Takao; Minami, Ryunosuke; Nakagoshi, Hideki; Adachi-Yamada, Takashi

2014-12-20

In standard cell division, the cells undergo karyokinesis and then cytokinesis. Some cells, however, such as cardiomyocytes and hepatocytes, can produce binucleate cells by going through mitosis without cytokinesis. This cytokinesis skipping is thought to be due to the inhibition of cytokinesis machinery such as the central spindle or the contractile ring, but the mechanisms regulating it are unclear. We investigated them by characterizing the binucleation event during development of the Drosophila male accessory gland, in which all cells are binucleate. The accessory gland cells arrested the cell cycle at 50 hours after puparium formation (APF) and in the middle of the pupal stage stopped proliferating for 5 hours. They then restarted the cell cycle and at 55 hours APF entered the M-phase synchronously. At this stage, accessory gland cells binucleated by mitosis without cytokinesis. Binucleating cells displayed the standard karyokinesis progression but also showed unusual features such as a non-round shape, spindle orientation along the apico-basal axis, and poor assembly of the central spindle. Mud, a Drosophila homolog of NuMA, regulated the processes responsible for these three features, the classical isoform Mud(PBD) and the two newly characterized isoforms Mud(L) and Mud(S) regulated them differently: Mud(L) repressed cell rounding, Mud(PBD) and Mud(S) oriented the spindle along the apico-basal axis, and Mud(S) and Mud(L) repressed central spindle assembly. Importantly, overexpression of Mud(S) induced binucleation even in standard proliferating cells such as those in imaginal discs. We characterized the binucleation in the Drosophila male accessory gland and examined mechanisms that regulated unusual morphologies of binucleating cells. We demonstrated that Mud, a microtubule binding protein regulating spindle orientation, was involved in this binucleation. We suggest that atypical functions exerted by three structurally different isoforms of Mud regulate

Usage of Vermiculite as Additive Material in Water-Based Drilling Muds

Directory of Open Access Journals (Sweden)

Onur Eser Kök

2018-05-01

Full Text Available Drilling mud is used in drilling operations to ensure well stability and to transport the cut-offs to the surface and is generally classified as; Spud, Lignosulfonate and Polymer types. Spud Mud is the simple mud and mostly used at the beginning of drilling operations. It is mainly composed of bentonite and water. With increasing depth, It is hard to keep well stability and to carry cuttings from the bottom of hole to the surface with the basic drilling fluid. Thus, some materials are used to maintain the rheological and filtration properties of the mud. One of them is vermiculite that is a general name of the hydrated ferromagnesian aluminium silicate group. It has expanded properties when heated. Like all clay minerals, the cation exchange capacity is very high and very similar to the montmorillonites in terms of high cation exchange capacity. In this study, the usage of vermiculite as an additive material in drilling muds was investigated. Spud muds containing vermiculite in different amounts were prepared. Then rheological and filtration analysis of the muds were done according to American Petroleum Institute (API RP-13B-1 Standard. When evaluated the results, AV reached 41cP, PV 27cP, YP 28lb/100ft2 , 10 sec. gel strength 17lb/100ft2 , 10 min. gel strength 26 lb/100ft2 and filtration 9cc. The results showed that the vermiculite can might be used as a viscosifier and fluid loss reducing additive material in the drilling mud.

Synchro-Betatron Stop-Bands Due to a Single Crab Cavity

Energy Technology Data Exchange (ETDEWEB)

Chao, A

2004-06-17

We analyze the stop-band due to crab cavities for horizontal tunes that are either close to integers or close to half integers. The latter case is relevant for today's electron/positron colliders. We compare this stop-band to that created by dispersion in an accelerating cavity and show that a single typical crab cavity creates larger stop-bands than a typical dispersion at an accelerating cavity. We furthermore analyze whether it is beneficial to place the crab cavity at a position where the dispersion and its slope vanish. We find that this choice is worth while if the horizontal tune is close to a half integer, but not if it is close to an integer. Furthermore we find that stop-bands can be avoided when the horizontal tune is located at a favorable side of the integer or the half integer. While we are here concerned with the installation of a single crab cavity in a storage ring, we show that the stop-bands can be weakened, although not eliminated, significantly when two crab cavities per ring are chosen suitably.

Inscuteable Regulates the Pins-Mud Spindle Orientation Pathway

Science.gov (United States)

Mauser, Jonathon F.; Prehoda, Kenneth E.

2012-01-01

During asymmetric cell division, alignment of the mitotic spindle with the cell polarity axis ensures that the cleavage furrow separates fate determinants into distinct daughter cells. The protein Inscuteable (Insc) is thought to link cell polarity and spindle positioning in diverse systems by binding the polarity protein Bazooka (Baz; aka Par-3) and the spindle orienting protein Partner of Inscuteable (Pins; mPins or LGN in mammals). Here we investigate the mechanism of spindle orientation by the Insc-Pins complex. Previously, we defined two Pins spindle orientation pathways: a complex with Mushroom body defect (Mud; NuMA in mammals) is required for full activity, whereas binding to Discs large (Dlg) is sufficient for partial activity. In the current study, we have examined the role of Inscuteable in mediating downstream Pins-mediated spindle orientation pathways. We find that the Insc-Pins complex requires Gαi for partial activity and that the complex specifically recruits Dlg but not Mud. In vitro competition experiments revealed that Insc and Mud compete for binding to the Pins TPR motifs, while Dlg can form a ternary complex with Insc-Pins. Our results suggest that Insc does not passively couple polarity and spindle orientation but preferentially inhibits the Mud pathway, while allowing the Dlg pathway to remain active. Insc-regulated complex assembly may ensure that the spindle is attached to the cortex (via Dlg) before activation of spindle pulling forces by Dynein/Dynactin (via Mud). PMID:22253744

Dead Sea mud packs for chronic low back pain.

Science.gov (United States)

Abu-Shakra, Mahmoud; Mayer, Amit; Friger, Michael; Harari, Marco

2014-09-01

Low back pain (LBP) is chronic disease without a curative therapy. Alternative and complementary therapies are widely used in the management of this condition. To evaluate the efficacy of home application of Dead Sea mud compresses to the back of patients with chronic LBP. Forty-six consecutive patients suffering from chronic LBP were recruited. All patients were followed at the Soroka University Rheumatic Diseases Unit. The patients were randomized into two groups: one group was treated with mineral-rich mud compresses, and the other with mineral-depleted compresses. Mud compresses were applied five times a week for 3 consecutive weeks. The primary outcome was the patient's assessment of the overall back pain severity. The score of the Ronald & Morris questionnaire served as a secondary outcome. Forty-four patients completed the therapy and the follow-up assessments: 32 were treated with real mud packs and 12 used the mineral-depleted packs. A significant decrease in intensity of pain, as described by the patients, was observed only in the treatment group. In this group, clinical improvement was clearly seen at completion of therapy and was sustained a month later. Significant improvement in the scores of the Roland & Morris questionnaire was observed in both groups. The data suggest that pain severity was reduced in patients treated with mineral-rich mud compresses compared with those treated with mineral-depleted compresses. Whether this modest effect is the result of a "true" mud effect or other causes can not be determined in this study.

Determination of rare earth elements in red mud by ICP-MS

International Nuclear Information System (INIS)

Kumar, Sanjukta A.; Suvarna, S.; Kiran Kumar, G.

2017-01-01

Red mud or red sludge is a highly alkaline waste product composed mainly of iron oxide that is generated in the industrial production of aluminum from bauxite. With about 77 million tons of this hazardous material being produced annually, red mud poses a serious disposal problem in the mining industry. Discharge of red mud is hazardous environmentally because of its alkalinity. Many studies have been conducted to develop uses of red mud. An estimated 2 to 3 million tones are used annually in the production of cement, road construction and as a source for iron. Potential applications include the production of low cost concrete, application to sandy soils to improve phosphorus cycling, amelioration of soil acidity, landfill capping and carbon sequestration. Red mud contains a large amount of iron along with appreciable concentrations of many strategic elements such as rare earth elements and therefore can be a source of valuable secondary raw material. This necessitates the elemental characterization of red mud. This paper presents an effective dissolution procedure using a mixture of phosphoric acid and nitric acid for red mud followed by determination of rare earth elements by ICP-MS. The method was validated by spike recovery experiments. The recoveries were found within 98 to 102 %. The relative standard deviation (RSD) of the method was found to be within 5 %

Invasive ants compete with and modify the trophic ecology of hermit crabs on tropical islands.

Science.gov (United States)

McNatty, Alice; Abbott, Kirsti L; Lester, Philip J

2009-05-01

Invasive species can dramatically alter trophic interactions. Predation is the predominant trophic interaction generally considered to be responsible for ecological change after invasion. In contrast, how frequently competition from invasive species contributes to the decline of native species remains controversial. Here, we demonstrate how the trophic ecology of the remote atoll nation of Tokelau is changing due to competition between invasive ants (Anoplolepis gracilipes) and native terrestrial hermit crabs (Coenobita spp.) for carrion. A significant negative correlation was observed between A. gracilipes and hermit crab abundance. On islands with A. gracilipes, crabs were generally restricted to the periphery of invaded islands. Very few hermit crabs were found in central areas of these islands where A. gracilipes abundances were highest. Ant exclusion experiments demonstrated that changes in the abundance and distribution of hermit crabs on Tokelau are a result of competition. The ants did not kill the hermit crabs. Rather, when highly abundant, A. gracilipes attacked crabs by spraying acid and drove crabs away from carrion resources. Analysis of naturally occurring N and C isotopes suggests that the ants are effectively lowering the trophic level of crabs. According to delta(15) N values, hermit crabs have a relatively high trophic level on islands where A. gracilipes have not invaded. In contrast, where these ants have invaded we observed a significant decrease in delta(15) N for all crab species. This result concurs with our experiment in suggesting long-term exclusion from carrion resources, driving co-occurring crabs towards a more herbivorous diet. Changes in hermit crab abundance or distribution may have major ramifications for the stability of plant communities. Because A. gracilipes have invaded many tropical islands where the predominant scavengers are hermit crabs, we consider that their competitive effects are likely to be more prominent in

Conservation status of the American horseshoe crab, (Limulus polyphemus): A regional assessment

Science.gov (United States)

Smith, David R.; Brockmann, H. Jane; Beekey, Mark A.; King, Timothy L.; Millard, Michael J.; Zaldívar-Rae, Jaime

2017-01-01

Horseshoe crabs have persisted for more than 200 million years, and fossil forms date to 450 million years ago. The American horseshoe crab (Limulus polyphemus), one of four extant horseshoe crab species, is found along the Atlantic coastline of North America ranging from Alabama to Maine, USA with another distinct population on the coasts of Campeche, Yucatán and Quintana Roo in the Yucatán Peninsula, México. Although the American horseshoe crab tolerates broad environmental conditions, exploitation and habitat loss threaten the species. We assessed the conservation status of the American horseshoe crab by comprehensively reviewing available scientific information on its range, life history, genetic structure, population trends and analyses, major threats, and conservation. We structured the status assessment by six genetically-informed regions and accounted for sub-regional differences in environmental conditions, threats, and management. The transnational regions are Gulf of Maine (USA), Mid-Atlantic (USA), Southeast (USA), Florida Atlantic (USA), Northeast Gulf of México (USA), and Yucatán Peninsula (México). Our conclusion is that the American horseshoe crab species is vulnerable to local extirpation and that the degree and extent of risk vary among and within the regions. The risk is elevated in the Gulf of Maine region due to limited and fragmented habitat. The populations of horseshoe crabs in the Mid-Atlantic region are stable in the Delaware Bay area, and regulatory controls are in place, but the risk is elevated in the New England area as evidenced by continuing declines understood to be caused by over-harvest. The populations of horseshoe crabs in the Southeast region are stable or increasing. The populations of horseshoe crabs in the Florida Atlantic region show mixed trends among areas, and continuing population reductions at the embayment level have poorly understood causes. Within the Northeast Gulf of Mexico, causes of population trends are

Assessing potential impacts of energized submarine power cables on crab harvests

Science.gov (United States)

Love, Milton S.; Nishimoto, Mary M.; Clark, Scott; McCrea, Merit; Bull, Ann Scarborough

2017-12-01

Offshore renewable energy facilities transmit electricity to shore through submarine power cables. Electromagnetic field emissions (EMFs) are generated from the transmission of electricity through these cables, such as the AC inter-array (between unit) and AC export (to shore) cables often used in offshore energy production. The EMF has both an electric component and a magnetic component. While sheathing can block the direct electric field, the magnetic field is not blocked. A concern raised by fishermen on the Pacific Coast of North America is that commercially important Dungeness crab (Metacarcinus magister Dana, 1852)) might not cross over an energized submarine power cable to enter a baited crab trap, thus potentially reducing their catch. The presence of operating energized cables off southern California and in Puget Sound (cables that are comparable to those within the arrays of existing offshore wind energy devices) allowed us to conduct experiments on how energized power cables might affect the harvesting of both M. magister and another commercially important crab species, Cancer productus Randall, 1839. In this study we tested the questions: 1) Is the catchability of crabs reduced if these animals must traverse an energized power cable to enter a trap and 2) if crabs preferentially do not cross an energized cable, is it the cable structure or the EMF emitted from that cable that deters crabs from crossing? In field experiments off southern California and in Puget Sound, crabs were given a choice of walking over an energized power cable to a baited trap or walking directly away from that cable to a second baited trap. Based on our research we found no evidence that the EMF emitted by energized submarine power cables influenced the catchability of these two species of commercially important crabs. In addition, there was no difference in the crabs' responses to lightly buried versus unburied cables. We did observe that, regardless of the position of the cable

Ecological effects of low toxicity oil-based mud drilling in the Beatrice oilfield

Energy Technology Data Exchange (ETDEWEB)

Addy, J M; Hartley, J P; Tibbetts, P J.C.

1984-12-01

To investigate the effects of drilling discharges on the seabed fauna, surveys were carried out in the Beatrice oilfield after drilling 13 wells with water-based muds, and then after one and five further wells had been drilled using low toxicity oil-based muds. Localized benthic effects were found after the water-based mud drilling. After the use of oil-based muds, the nature of the effects was different, although there was little increase in the area involved. Possible reasons for this are discussed and burial and organic enrichment are suggested as the major influences. It is concluded that the use of low toxicity oil-based mud at Beatrice has resulted in only limited benthic effects, suggesting that the use of these muds is environmentally acceptable.

The Crab Nebula flaring activity

Energy Technology Data Exchange (ETDEWEB)

Montani, G., E-mail: giovanni.montani@frascati.enea.it [ENEA – C.R, UTFUS-MAG, via Enrico Fermi 45, I-00044 Frascati (RM) (Italy); Dipartimento di Fisica, Università di Roma “Sapienza”, p.le Aldo Moro 5, I-00185 Roma (Italy); Bernardini, M.G. [INAF – Osservatorio Astronomico di Brera, via Bianchi 46, I-23807 Merate (Italy)

2014-12-12

The discovery made by AGILE and Fermi of a short time scale flaring activity in the gamma-ray energy emission of the Crab Nebula is a puzzling and unexpected feature, challenging particle acceleration theory. In the present work we propose the shock-induced magnetic reconnection as a viable mechanism to explain the Crab flares. We postulate that the emitting region is located at ∼10{sup 15} cm from the central pulsar, well inside the termination shock, which is exactly the emitting region size as estimated by the overall duration of the phenomenon ∼1 day. We find that this location corresponds to the radial distance at which the shock-induced magnetic reconnection process is able to accelerate the electrons up to a Lorentz factor ∼10{sup 9}, as required by the spectral fit of the observed Crab flare spectrum. The main merit of the present analysis is to highlight the relation between the observational constraints to the flare emission and the radius at which the reconnection can trigger the required Lorentz factor. We also discuss different scenarios that can induce the reconnection. We conclude that the existence of a plasma instability affecting the wind itself as the Weibel instability is the privileged scenario in our framework.

Reagent for treating clay drilling muds

Energy Technology Data Exchange (ETDEWEB)

Tkachenko, P V; Leshchinskiy, P A; Shnaper, B I; Zinchuk, I F; Zlobin, V P

1982-01-01

A reagent is proposed for treating clay drilling muds. It contains lignite, caustic soda and modifying agent. It is distinguished by the fact that in order to reduce the cost of the reagent with simultaneous decrease in the viscosity and static shear stress of the drilling mud, it additionally contains iron sulfate, and the modifying agent contained is wastes of carbonic acid production with the following ratio of components (parts by weight): lignite 10.0-15.0, caustic soda 2.0-3.0, wastes of carbonic acid production 0.5-0.75; iron sulfate 1.0-2.0.

Removal of hexavalent chromium by using red mud activated with cetyltrimethylammonium bromide.

Science.gov (United States)

Li, Deliang; Ding, Ying; Li, Lingling; Chang, Zhixian; Rao, Zhengyong; Lu, Ling

2015-01-01

The removal of hexavalent chromium [Cr(VI)] from aqueous solution by using red mud activated with cetyltrimethylammonium bromide (CTAB) was studied. The optimum operation parameters, such as CTAB concentration, pH values, contact time, and initial Cr(VI) concentration, were investigated. The best concentration of CTAB for modifying red mud was found to be 0.50% (mCTAB/VHCl,0.6 mol/L). The lower pH (mud activated with CTAB can greatly improve the removal ratio of Cr(VI) as high as four times than that of original red mud. Adsorption equilibrium was reached within 30 min under the initial Cr(VI) concentration of 100 mg L(-1). The isotherm data were analysed using Langmuir and Freundlich models. The adsorption of Cr(VI) on activated red mud fitted well to the Langmuir isotherm model, and the maximum adsorption capacity was estimated as 22.20 mg g(-1) (Cr/red mud). The adsorption process could be well described using the pseudo-second-order model. The result shows that activated red mud is a promising agent for low-cost water treatment.

Investigation of the Dashigil mud volcano (Azerbaijan) using beryllium-10

Energy Technology Data Exchange (ETDEWEB)

Kim, K.J., E-mail: kjkim@kigam.re.kr [Korea Geological Research Division, Korea Institute of Geoscience and Mineral Resources, Daejeon 305-350 (Korea, Republic of); Baskaran, M.; Jweda, J. [Department of Geology, Wayne State University, Detroit, MI 48202 (United States); Feyzullayev, A.A.; Aliyev, C. [Geology Institute of the Azerbaijan National Academy of Sciences (ANAS), Baku, AZ 1143 (Azerbaijan); Matsuzaki, H. [MALT, University of Tokyo, Tokyo (Japan); Jull, A.J.T. [NSF Arizona AMS Lab, University of Arizona, AZ 85721 (United States)

2013-01-15

We collected and analyzed five sediments from three mud volcano (MV) vents and six suspended and bottom sediment samples from the adjoining river near the Dashgil mud volcano in Azerbaijan for {sup 10}Be. These three MV are found among the 190 onshore and >150 offshore MV in this region which correspond to the western flank of the South Caspian depression. These MVs overlie the faulted and petroleum-bearing anticlines. The {sup 10}Be concentrations and {sup 10}Be/{sup 9}Be ratios are comparable to the values reported for mud volcanoes in Trinidad Island. It appears that the stable Be concentrations in Azerbaijan rivers are not perturbed by anthropogenic effects and are comparable to the much older sediments (mud volcano samples). The {sup 10}Be and {sup 9}Be concentrations in our river sediments are compared to the global data set and show that the {sup 10}Be values found for Kura River are among the lowest of any river for which data exist. We attribute this low {sup 10}Be concentration to the nature of surface minerals which are affected by the residual hydrocarbon compounds that occur commonly in the study area in particular and Azerbaijan at large. The concentrations of {sup 40}K and U-Th-series radionuclides ({sup 234}Th, {sup 210}Pb, {sup 226}Ra, and {sup 228}Ra) indicate overall homogeneity of the mud volcano samples from the three different sites. Based on the {sup 10}Be concentrations of the mud volcano samples, the age of the mud sediments could be at least as old as 4 myr.

A drilling mud for drilling wells in collapsing rocks

Energy Technology Data Exchange (ETDEWEB)

Bochkarev, G P; Anderson, B A; Minkhayrov, K A; Sharipov, A U

1982-01-01

In a known drilling mud for drilling wells in collapsing rocks, which contains clay, sodium silicate and polyacrylamide (PAA), in order to increase its specific electrical resistance and to increase the strengthening properties, a silicoorganic liquid is additionally introduced into its composition with the following component ratio (percent): clay, 5 to 7; sodium silicate, 5 to 7; polyacrylamide, 0.3 to 0.5; silicoorganic liquid, GKZh-94, 0.5 to 1.5 and water, the remainder. The GKZh-94 is a chemical compound based on alkylphenylchlorsilanes and substituted ethers of orthosilicic acid, used for waterproofing fabrics and soils. The addition of GKZh-94 provides the required values of the specific electric resistance of the mud and does not distort the gas logging indications. The proposed mud has low water production (4 to 6 cubic centimeters), optimal viscosity (25 to 31 seconds) and high structural and mechanical properties. Its strengthening properties are substantially above those of the known mud.

Binding of Vapour-Phase Mercury (Hg0) on Chemically Treated Bauxite Residues (Red Mud)

Science.gov (United States)

In this study, Hg capture using red mud, seawater-neutralized red mud, and acid-treated red mud is evaluated and compared to other, more conventional sorbent materials. Red mud (also known as bauxite residue) is a by-product of extracting alumina from ground bauxite ore by treati...

AML (Advanced Mud Logging: First Among Equals

Directory of Open Access Journals (Sweden)

T. Loermans

2017-09-01

Full Text Available During the past ten years an enormous development in mud logging technology has been made. Traditional mud logging was only qualitative in nature, and mudlogs could not be used for the petrophysical well evaluations which form the basis for all subsequent activities on wells and fields. AML however can provide quantitative information, logs with a reliability, trueness and precision like LWD and WLL. Hence for well evaluation programmes there are now three different logging methods available, each with its own pros and cons on specific aspects: AML, LWD and WLL. The largest improvements have been made in mud gas analysis and elemental analysis of cuttings. Mud gas analysis can yield hydrocarbon fluid composition for some components with a quality like PVT analysis, hence not only revolutionising the sampling programme so far done with only LWD/WLL, but also making it possible to geosteer on fluid properties. Elemental analysis of cuttings, e.g. with XRF, with an ability well beyond the capabilities of the spectroscopy measurements possible earlier with LWD/WLL tools, is opening up improved ways to evaluate formations, especially of course where the traditional methods are falling short of requirements, such as in unconventional reservoirs. An overview and specific examples of these AML logs is given, from which it may be concluded that AML now ought to be considered as “first among its equals”.

CO2 flux from Javanese mud volcanism.

Science.gov (United States)

Queißer, M; Burton, M R; Arzilli, F; Chiarugi, A; Marliyani, G I; Anggara, F; Harijoko, A

2017-06-01

Studying the quantity and origin of CO 2 emitted by back-arc mud volcanoes is critical to correctly model fluid-dynamical, thermodynamical, and geochemical processes that drive their activity and to constrain their role in the global geochemical carbon cycle. We measured CO 2 fluxes of the Bledug Kuwu mud volcano on the Kendeng Fold and thrust belt in the back arc of Central Java, Indonesia, using scanning remote sensing absorption spectroscopy. The data show that the expelled gas is rich in CO 2 with a volume fraction of at least 16 vol %. A lower limit CO 2 flux of 1.4 kg s -1 (117 t d -1 ) was determined, in line with the CO 2 flux from the Javanese mud volcano LUSI. Extrapolating these results to mud volcanism from the whole of Java suggests an order of magnitude total CO 2 flux of 3 kt d -1 , comparable with the expected back-arc efflux of magmatic CO 2 . After discussing geochemical, geological, and geophysical evidence we conclude that the source of CO 2 observed at Bledug Kuwu is likely a mixture of thermogenic, biogenic, and magmatic CO 2 , with faulting controlling potential pathways for magmatic fluids. This study further demonstrates the merit of man-portable active remote sensing instruments for probing natural gas releases, enabling bottom-up quantification of CO 2 fluxes.

Conditioning of red mud for subsequent titanium and scandium recovery. A conceptual design study

Energy Technology Data Exchange (ETDEWEB)

Alkan, G.; Xakalashe, B.; Kaussen, F.; Friedrich, Bernd [RWTH Aachen Univ. (Germany). IME Inst. of Process Metallurgy and Metal Recycling; Yagmurlu, B. [RWTH Aachen Univ. (Germany). IME Inst. of Process Metallurgy and Metal Recycling; MEAB Chemie Technik GmbH, Aachen (Germany)

2017-03-15

Leaching experiments were undertaken on red mud materials (red mud and red mud slag). The red mud slag was produced via the carbothermic reduction of red mud at high temperatures (T > 1500 C) via SAF treatment. Furthermore, iron was recovered in the smelting step to the metal phase. Ti and Sc were successfully recovered from the red mud materials by hydrometallurgical treatment. For both critical metals, it was found that sulfuric acid was the best mineral acid among others. Since direct red mud leaching had some shortcomings, a route designed to overcome them is proposed. For optimal Ti and Sc recovery from red mud a promising process flowsheet combining pyrometallurgical and hydrometallurgical treatment is proposed as follows: pyrometallurgical processing (fluxed smelting to produce calcium oxide based slag phases and controlled cooling for crystalline and glassy slags), leaching for maximized Ti- and Sc extraction and followed by a multistage precipitation (for metal recovery and solution purification). Initial trial results showed that the proposed process is promising.

Hard X-ray Variations in the Crab Nebula

Science.gov (United States)

Wilson-Hodge, Colleen A.; Cherry, M. L.; Case, G. L.; Baumgartner, W. H.; Beklen, E.; Bhat, P. N.; Briggs, M. S.; Camero-Arranz, A.; Connaughton, V.; Finger, M. H.;

Natural radionuclides in bauxitic tailings (Red-Mud) in the Gulf of Corinth, Greece

International Nuclear Information System (INIS)

Papatheodorou, G.; Maratou, A.; Ferentinos, G.; Papaefthymiou, H.

2004-01-01

A detailed environmental survey was carried out in the central Gulf of Corinth in order to determine radionuclides in the bauxite ed-mud tailings which have been discharged on the sea floor by a Bauxite Processing Plant (Aluminio Ellados A.E). The discharge of bauxitic tailings via two pipelines at a water depth of 100 m, in Antikyra Bay (Northern Gulf of Corinth), has resulted in the formation of two red-mud mound-like deposits. The red-mud deposits at the mouth of the out falls, are not stable and very often red-mud masses are detached from the two main deposits and are transported to the Corinth central basin, by turbidity currents, at a water depth of 850 m and about 17 km away from the main deposits. Thus, at the Antikyra bay, the red-mud has formed a surficial veneer (0.5-2.0 cm) on the sea floor. On the Corinth central basin floor the red mud has formed successive red-mud layers which are interrupted by layers of natural mud. Fifteen gravity cores have been selected from the studied area and a number of bauxite samples have been collected from mines that supply the bauxite processing plant. Red-mud, natural mud and bauxite samples were analyzed for 238 U 226 Ra, 232 Th, 40 K, and 137 Cs by direct gamma spectrometry. The study of radionuclides concentrations has shown that: (a) the enrichment factor of radionuclides in the red-mud in the main deposit at the mouth of the out falls, in relation to bauxite samples, is about 2.0, (b) the enrichment factor of 238 U, 226 Ra and 232 Th in the red-mud in the main deposit and the central basin, in relation to natural sediments below, is visibly higher than 1.0 (2.0-19.0) whilst 40 K exhibits the opposite trend, and (c) the enrichment/dilution factor of radionuclides in the red-mud surficial veneer at the Antikyra Bay, in relation to the natural sediments below, is ranging between 0.4 and 3.5. (author)

The anaerobic digestion of organic matter in sugarbeet mud

NARCIS (Netherlands)

Keizer, M.G.; Haan, de F.A.M.; Blom, J.J.C.; Knaapen, J.W.P.M.

1981-01-01

Storage of sugar-beet mud in the traditional way, i.e., direct dewatering after pumping the slurry in storage basins, may cause odor nuisance because of digestion of organic substances. In order to prevent these bad odor problems the mud should remain submerged during the digestion period. No

50 CFR 680.6 - Crab economic data report (EDR).

Science.gov (United States)

2010-10-01

... sales gross revenue. CR fishery code, pounds sold, and gross revenue. (iii) CDQ crab lease costs. CR... sales, gross revenue. CR fishery code, species code, pounds sold, and gross revenue; (iii) CDQ and IFQ... materials, equipment and supplies; re-packing costs, broker fees and promotions for BSAI crab sales (by CR...

Habits and customs of crab catchers in southern Bahia, Brazil.

Science.gov (United States)

Firmo, Angélica M S; Tognella, Mônica M P; Tenório, Gabrielle D; Barboza, Raynner R D; Alves, Rômulo R N

2017-08-23

Brazilian mangrove forests are widely distributed along the coast and exploited by groups of people with customs and habits as diverse as the biology of the mangrove ecosystems. This study identifies different methods of extracting crabs that inhabit the mangrove belts; some of these activities, such as catching individual crabs by hand, are aimed at maintaining natural stocks of this species in Mucuri (south Bahia), Brazil. In the studied community, illegal hunting activities that violate Brazilian legislation limiting the use of tangle-netting in mangrove ecosystem were observed. According to our observations, fishermen, to catch individual crabs, use the tangle-netting technique seeking to increase income and are from families that have no tradition of extraction. This analysis leads us to conclude that catchers from economically marginalised social groups enter mangroves for purposes of survival rather than for purposes of subsistence, because the catching by tangle-netting is a predatory technique. Tangle-netting  technique increase caught but also increases their mortality rate. We emphasise that traditional catching methods are unique to Brazil and that manual capturing of crab should be preserved through public policies aimed at maintaining the crab population.

MUD and Self Efficacy.

Science.gov (United States)

Lee, Kwan Min

2000-01-01

Proposes a theoretical framework for analyzing the effect of MUD (Multi-User Dungeons) playing on users' self-efficacy by applying Bandura's social learning theory, and introduces three types of self-efficacy: computer self-efficacy; social self-efficacy; and generalized self-efficacy. Considers successful performance, vicarious experience,…

Crab cavities: Past, present, and future of a challenging device

Energy Technology Data Exchange (ETDEWEB)

Wu, Q. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-05-03

In two-ring facilities operating with a crossing-angle collision scheme, luminosity can be limited due to an incomplete overlapping of the colliding bunches. Crab cavities then are introduced to restore head-on collisions by providing the destined opposite deflection to the head and tail of the bunch. An increase in luminosity was demonstrated at KEKB with global crab-crossing, while the Large Hardron Collider (LHC) at CERN currently is designing local crab crossing for the Hi-Lumi upgrade. Future colliders may investigate both approaches. In this paper, we review the challenges in the technology, and the implementation of crab cavities, while discussing experience in earlier colliders, ongoing R&D, and proposed implementations for future facilities, such as HiLumi-LHC, CERN’s compact linear collider (CLIC), the international linear collider (ILC), and the electron-ion collider under design at BNL (eRHIC).

Crab cavities: Past, present, and future of a challenging device

International Nuclear Information System (INIS)

Wu, Q.

2015-01-01

In two-ring facilities operating with a crossing-angle collision scheme, luminosity can be limited due to an incomplete overlapping of the colliding bunches. Crab cavities then are introduced to restore head-on collisions by providing the destined opposite deflection to the head and tail of the bunch. An increase in luminosity was demonstrated at KEKB with global crab-crossing, while the Large Hardron Collider (LHC) at CERN currently is designing local crab crossing for the Hi-Lumi upgrade. Future colliders may investigate both approaches. In this paper, we review the challenges in the technology, and the implementation of crab cavities, while discussing experience in earlier colliders, ongoing R&D, and proposed implementations for future facilities, such as HiLumi-LHC, CERN@@@s compact linear collider (CLIC), the international linear collider (ILC), and the electron-ion collider under design at BNL (eRHIC).

Crab Cavities: Past, Present, and Future of a Challenging Device

CERN Document Server

Wu, Q

2015-01-01

In two-ring facilities operating with a crossing-angle collision scheme, luminosity can be limited due to an incomplete overlapping of the colliding bunches. Crab cavities then are introduced to restore head-on collisions by providing the destined opposite deflection to the head and tail of the bunch. An increase in luminosity was demonstrated at KEKB with global crab- crossing, while the Large Hardron Collider (LHC) at CERN currently is designing local crab crossing for the Hi-Lumi upgrade. Future colliders may investigate both approaches. In this paper, we review the challenges in the technology, and the implementation of crab cavities, while discussing experience in earlier colliders, ongoing R&D, and proposed implementations for future facilities, such as HiLumi-LHC, CERN’s compact linear collider (CLIC), the international linear collider (ILC), and the electronion collider under design at BNL (eRHIC).

Dungeness crab survey for the Southwest Ocean Disposal Site off Grays Harbor, Washington, June 1990

Energy Technology Data Exchange (ETDEWEB)

Higgins, B.J.; Pearson, W.H. (Battelle/Marine Sciences Lab., Sequim, WA (United States))

1991-09-01

As part of the Grays Harbor Navigation Improvement Project, the Seattle District of the US Army Corps of Engineers has begun active use of the Southwest Ocean Disposal Site off Grays Harbor, Washington. This survey was to verify that the location of the area of high crab density observed during site selection surveys has not shifted into the Southeast Ocean Disposal Site. In June 1990, mean densities of juvenile Dungeness crab were 146 crab/ha within the disposal site and 609 crab/ha outside ad north of the disposal site. At nearshore locations outside the disposal site, juvenile crab density was 3275 crab/ha. Despite the low overall abundance, the spatial distribution of crab was such that the high crab densities in 1990 have remained outside the Southwest Ocean Disposal Site. The survey data have confirmed the appropriateness of the initial selection of the disposal site boundaries and indicated no need to move to the second monitoring tier. 8 refs., 9 figs., 2 tabs.

Summary of CARE-HHH Mini-Workshop on LHC Crab Cavity Validation, 21 August 2008

CERN Document Server

Calaga, R; Garoby, R; Linnecar, T; Tomás, R; Zimmermann, F; CERN. Geneva. BE Department

2008-01-01

A global LHC crab-cavity collaboration is rapidly advancing the R&D of a complete crab cavity cryomodule and performing the associated beam dynamics simulations compatible with a prototype test in the phase 0/I upgrade with the aim of establishing a full crab crossing scheme for the phase II upgrade of the LHC. A one day CARE-HHH mini-workshop was held on August 21, 2008 at CERN to discuss crab crossing in the LHC phase 0/I & II upgrades and this reports summarizes the activities of the four sessions that took place during the workshop. The goals of this crab-cavity workshop were fourfold: (1) to discuss prospects of crab cavities in LHC upgrades (2) to review the status of the cryomodule development and beam dynamics, (3) to establish validity requirements for LHC crab cavities which need to be demonstrated prior to their installation into the LHC, and (4) to provide guidance & coordination for the global collaborators.

Aerobic Degradation of Drill Muds by Axenic and Mixed Bacterial ...

African Journals Online (AJOL)

Prof. Ogunji

significant difference in the degradation of the drilling muds by the isolates (p > 0.05). ... the potentials of some indigenous bacteria to biodegrade drilling muds used in ... transported to the laboratory aseptically for evaluation, in labeled plastic.

The "Mud-volcanoes route" (Emilia Apennines, northern Italy)

Science.gov (United States)

Coratza, Paola; Castaldini, Doriano

2016-04-01

In the present paper the "Mud-volcanoes route" (MVR), an itinerary unfolds across the districts of Viano, Sassuolo, Fiorano Modenese and Maranello, in which part of the Emilia mud volcanoes fields are located, is presented. The Mud-volanoes route represents an emotional journey that connects places and excellences through the geological phenomenon of mud volcanoes, known with the local name "Salse". The Mud Volcanoes are created by the surfacing of salt water and mud mixed with gaseous and liquid hydrocarbons along faults and fractures of the ground. The name "Salsa"- from Latin salsus - results from the"salt" content of these muddy waters, ancient heritage of the sea that about a million years ago was occupying the current Po Plain. The "Salse" may take the shape of a cone or a level-pool according to the density of the mud. The Salse of Nirano, in the district of Fiorano Modenese, is one of the most important in Italy and among the most complex in Europe. Less extensive but equally charming and spectacular, are the "Salse" located in the districts of Maranello (locality Puianello), Sassuolo (locality Montegibbio) and Viano (locality Casola Querciola and Regnano). These fascinating lunar landscapes have always attracted the interest of researchers and tourist.The presence on the MVR territory of ancient settlements, Roman furnaces and mansions, fortification systems and castles, besides historic and rural buildings, proves the lasting bond between this land and its men. In these places, where the culture of good food has become a resource, we can find wine cellars, dairy farms and Balsamic vinegar factories that enable us to appreciate unique worldwide products. This land gave also birth to some personalities who created unique worldwide famous values, such as the myth of the Ferrrari, the ceramic industry and the mechatronics. The MVR is represented in a leaflet containing, short explanation, photos and a map in which are located areas with mud volcanoes, castles

Sympatric occurrence and population dynamics of Scylla spp. in equatorial climate: Effects of rainfall, temperature and lunar phase

Science.gov (United States)

Fazhan, Hanafiah; Waiho, Khor; Darin Azri, Mohammad Farhan; Al-Hafiz, Ismail; Norfaizza, Wan Ibrahim Wan; Megat, Fadhlul Hazmi; Jasmani, Safiah; Ma, Hongyu; Ikhwanuddin, Mhd

2017-11-01

Mud crabs (Scylla spp.) are known to exist sympatrically in the wild. However, information on their population dynamics and the influence of climate parameters and lunar phase, especially along the equatorial region, are limited. Four sampling stations representing three seas (the Strait of Malacca, South China Sea and Sulu Sea) along the equator were selected. Mud crabs were collected using baited traps during spring tides from April 2012 to July 2013. All three Scylla species, S. olivacea, S. tranquebarica and S. paramamosain live in sympatry in the three seas. Scylla olivacea is the most prevalent species in the Strait of Malacca and South China Sea, whereas S. paramamosain dominates the Sulu Sea. The total crab abundance was not affected by rainfall or temperature. The abundance of S. tranquebarica in Strait of Malacca was negatively correlated with temperature and positively correlated with rainfall whereas the abundance of S. paramamosain positively correlated with temperature only at South China Sea. Scylla tranquebarica was the largest in terms of body size and it showed interchanging abundance trends with S. paramamosain. The average body size of S. paramamosain did not differ significantly with that of S. tranquebarica and S. olivacea. This decrease is most likely attributed to overfishing. Significant seasonal fluctuations in mean carapace width were detected in S. tranquebarica and S. paramamosain, but not in S. olivacea. The monthly sex ratio of all three species occasionally fluctuates above the equal sex ratio value. Lunar phase did not affect species abundance, but males and females were significantly heavier during full moon. These findings serve as a baseline of seasonal variation in crab population dynamics that are useful in mud crab fisheries and resource management.

Experimental Study of Goaf Filling Materials Based on Red Mud

Science.gov (United States)

Mu, Mangen; Gao, Xiaozhen; Guo, Taoming; Hu, Xinping

2018-01-01

Red mud as soild waste is difficult to treatment. Goaf filling materials can make a large use of red mud. By the experimental study,we find that the red mud, fly ash, ground slag and desulfida-tion gypsum can be used to make goaf filling materials based on the principle of alkali excitation and metalion stability.Through the control variable method, we find that the optimal proportion of goaf filling materials based on red mud is red mud 55%, fly ash 30%, cement 7.5%, fly ash 2.5%, desulfurization gypsum 5%, admixture 1%, and water solid ratio=1:1.2.The 28days final material strength was 2.0 MPa,which achives the technical specification requirements.Through the test of SEM, XRD and IR, it is indicated that the strength formation of goaf filling material based on red mud is from the unformed linking hydration products of amorphous alkali excitation system. With curing time from 3 to 7 days, the unformed linking hydration products grown a lot of vitreous hydration products. When hydration reaction basicly finished after 28 days, the hydration products have developed into a large volume of massive vitreous with an extremely dense structure. The Ca2SiO3 mineral phase is significantly reduced, which is participate in hydration reactions. The decrease of Ca2SiO3 indicates that the Si-O bond in the system have been ruptured and reorganized.

A glitch in the Crab pulsar (PSR B0531+21)

Science.gov (United States)

Shaw, Benjamin; Lyne, Andrew; Bassa, Cees; Breton, Rene; Jordan, Christine; Keith, Michael; Mickaliger, Mitchell B.; Stappers, Benjamin; Weltevrede, Patrick

2018-05-01

We have detected a glitch in the Crab pulsar, B0531+21, on 2018-04-29. The Crab pulsar is regularly monitored with the 42-ft and Lovell telescopes at the Jodrell Bank Observatory as part of the pulsar timing programme.

Delay Pressure Detection Method to Eliminate Pump Pressure Interference on the Downhole Mud Pressure Signals

Directory of Open Access Journals (Sweden)

Yue Shen

2013-01-01

Full Text Available The feasibility of applying delay pressure detection method to eliminate mud pump pressure interference on the downhole mud pressure signals is studied. Two pressure sensors mounted on the mud pipe in some distance apart are provided to detect the downhole mud continuous pressure wave signals on the surface according to the delayed time produced by mud pressure wave transmitting between the two sensors. A mathematical model of delay pressure detection is built by analysis of transmission path between mud pump pressure interference and downhole mud pressure signals. Considering pressure signal transmission characteristics of the mud pipe, a mathematical model of ideal low-pass filter for limited frequency band signal is introduced to study the pole frequency impact on the signal reconstruction and the constraints of pressure sensor distance are obtained by pole frequencies analysis. Theoretical calculation and numerical simulation show that the method can effectively eliminate mud pump pressure interference and the downhole mud continuous pressure wave signals can be reconstructed successfully with a significant improvement in signal-to-noise ratio (SNR in the condition of satisfying the constraints of pressure sensor distance.

Mud diaprism and it's effect on the hydrocarbon system in the south Caspian

International Nuclear Information System (INIS)

Baganz, O.W.; Ballard, J.H.; Krenov, M.

2002-01-01

Full text : Mud diapirism plays a special role in the geology and petroleum system of the south Caspian basin. Hundreads of mud intrusions penetrate the thick Plio-Pleistocene section. This article talks in detail about aspects of the influence of mud diapirs and their related with mud volcanoes on the generation and trapping of hydrocarbons. Some of these aspects are : 1) The influence on the sedimentation; 2) Structural impact; 3) Stress and strain in the surrounded formations; 4) Thermal effect; 5) Pressure effect. All these aspects of the diapiric and mud-volcanic activity should be kept in mind during the volumetric calculations and play evaluation.

Acanthocephala Parasite (Profilicollis spp.) Loads in Correlation to Pacific Mole Crab (Emerita analoga) Size

Science.gov (United States)

Cheng, T.; Huang, S.; Galathe, M.; Jenkins, M.; Ramirez, A.; Crosby, L.; Barrera, J.; FitzHoward, S.

2013-12-01

Since 2002, San Francisco Bay students have been conducting marine ecosystem monitoring through a joint project with the Long-term Monitoring Program and Experiential Training for Students (LiMPETS), in conjunction with the Gulf of Farallones National Marine Sanctuary. Each year students collect population and demographic data on Pacific mole crabs (Emerita analoga), an indicator species that lives in the sandy beach habitat in temperate regions along the Pacific Ocean. Pacific mole crabs are filter feeding crustaceans that inhabit the intertidal swash zone and are known to be an intermediate host for parasitic ';spiny-headed' worms in the phylum Acanthocephala (Profilicollis spp.). Sampling takes place during their reproductive period, which occurs from spring to fall, and includes measuring total body length of the Pacific mole crabs and dissecting them to determine presence of Acanthocephalan parasites. We hypothesize that due to larger body mass, larger Pacific mole crabs will have a greater number of Acanthocephala parasites.We conducted several analyses using the LiMPETS long-term data. Specifically, we compared body length, crab gender, and parasite abundance from Pacific mole crabs sampled from four beaches located in the county and city of San Francisco. Our results indicated that larger Pacific mole crabs do not necessarily have more parasites, but are more likely to have at least one parasite, while female Pacific mole crabs carrying eggs, have more parasites than males or females without eggs. We also found that parasite loads per mole crab was highest in the spring. Further analysis will be conducted to determine factors affecting Pacific mole crab parasite loads. Studying Pacific mole crabs help evaluate the health of California's intertidal systems and how human activities, geologic changes, and climate changes all make huge impacts to the intertidal ecosystems.

Simulating cryptic movements of a mangrove crab : Recovery phenomena after small scale fishery

NARCIS (Netherlands)

Piou, C.; Berger, U.; Hildenbrandt, H.; Grimm, V.; Diele, K.; D'Lima, C.

2007-01-01

The semi-terrestrial burrowing crab Ucides cordatus is an important ecological component and economic resource of Brazilian mangrove forests. The crab population of the Caete peninsula (the location of our study site) has been exploited for the last 40 years. Recovery of fished areas by crabs from

Reproductive biology of the female Jonah crab from the Maryland-Virginia Coastal Zone

Science.gov (United States)

Dunn, H.; Stevens, B. G.

2016-02-01

Jonah crabs, Cancer borealis, have long been considered a bycatch of the lobster industry. Jonah crab harvest is not regulated, there are no fishing size limits, nor restrictions to protect females. The study sampled Jonah crabs from one area in the Maryland-Virginia coastal zone from a local fishing vessel in June and July of 2015. This study is based on examination of the gross anatomy of 49 crabs and on histological preparations from 29 crabs. Ovary development stages were created and ordered based on area of oocytes, color and size of ovary, and the presence of sperm plugs. Four stages were observed but five are identifiable. Size at 50% sexual maturity (SM50), for females, as indicated by vulvar condition and oocyte area, was estimated to be 49.46 mm carapace length (CL). No prior information or study has been published concerning female Jonah crabs. This fishery-independent data is vital to ensure long-term sustainability, and develop appropriate management for this species.

 The diversity of horseshoe crabs - protecting an endangered resource

DEFF Research Database (Denmark)

Funch, Peter; Cong, Nguyen Van; Intanai, Itsara

Horseshoe crabs are fascinating inhabitants of the sea represented by four living species, where three species live in Asia, while the fourth species lives on the East coast of North America. Ancient fossils, dating back to Ordovician 445 million years ago looks so similar to recent horseshoe crabs...... that people often call them "living fossils". Unfortunately, the existing populations are threatened by overfishing of the adults as well as by destruction and pollution of the beaches where they mate and deposit their eggs. All four extant species are on IUCN Red List of Threatened Species. The blue blood...... of the horseshoe crabs saves thousands of human lives every year. An extract from their blood are used worldwide to determine whether medicine, blood donations, and medical supplies are infected by bacteria or contain toxins. Horseshoe crabs are also fished for human consumption in Asia, are heavily used as bait...

Boxer crabs induce asexual reproduction of their associated sea anemones by splitting and intraspecific theft

Directory of Open Access Journals (Sweden)

Yisrael Schnytzer

2017-01-01

Full Text Available Crabs of the genus Lybia have the remarkable habit of holding a sea anemone in each of their claws. This partnership appears to be obligate, at least on the part of the crab. The present study focuses on Lybia leptochelis from the Red Sea holding anemones of the genus Alicia (family Aliciidae. These anemones have not been found free living, only in association with L. leptochelis. In an attempt to understand how the crabs acquire them, we conducted a series of behavioral experiments and molecular analyses. Laboratory observations showed that the removal of one anemone from a crab induces a “splitting” behavior, whereby the crab tears the remaining anemone into two similar parts, resulting in a complete anemone in each claw after regeneration. Furthermore, when two crabs, one holding anemones and one lacking them, are confronted, the crabs fight, almost always leading to the “theft” of a complete anemone or anemone fragment by the crab without them. Following this, crabs “split” their lone anemone into two. Individuals of Alicia sp. removed from freshly collected L. leptochelis were used for DNA analysis. By employing AFLP (Fluorescence Amplified Fragments Length Polymorphism it was shown that each pair of anemones from a given crab is genetically identical. Furthermore, there is genetic identity between most pairs of anemone held by different crabs, with the others showing slight genetic differences. This is a unique case in which one animal induces asexual reproduction of another, consequently also affecting its genetic diversity.

Characterization of the antimicrobial peptide family defensins in the Tasmanian devil (Sarcophilus harrisii), koala (Phascolarctos cinereus), and tammar wallaby (Macropus eugenii).

Science.gov (United States)

Jones, Elizabeth A; Cheng, Yuanyuan; O'Meally, Denis; Belov, Katherine

2017-03-01

Defensins comprise a family of cysteine-rich antimicrobial peptides with important roles in innate and adaptive immune defense in vertebrates. We characterized alpha and beta defensin genes in three Australian marsupials: the Tasmanian devil (Sarcophilus harrisii), koala (Phascolarctos cinereus), and tammar wallaby (Macropus eugenii) and identified 48, 34, and 39 defensins, respectively. One hundred and twelve have the classical antimicrobial peptides characteristics required for pathogen membrane targeting, including cationic charge (between 1+ and 15+) and a high proportion of hydrophobic residues (>30%). Phylogenetic analysis shows that gene duplication has driven unique and species-specific expansions of devil, koala, and tammar wallaby beta defensins and devil alpha defensins. Defensin genes are arranged in three genomic clusters in marsupials, whereas further duplications and translocations have occurred in eutherians resulting in four and five gene clusters in mice and humans, respectively. Marsupial defensins are generally under purifying selection, particularly residues essential for defensin structural stability. Certain hydrophobic or positively charged sites, predominantly found in the defensin loop, are positively selected, which may have functional significance in defensin-target interaction and membrane insertion.

Designing a suitable alternative to oil-based mud

International Nuclear Information System (INIS)

Holgate, M.; Irwin, G.; Cousins, L.

1991-01-01

This paper reports on wireline logging problems which have plagued the reservoir section of development wells in Welton oil field in the East Midlands area of England. And resulting incomplete or poor-quality logging data spurred a look at ways of improving hole conditions. Oil-based muds often are seen as the ideal solution, but they are expensive. Their use also commits the operator to additional costs from safeguarding personnel and limiting environmental impact. Such expense was initiated to develop a cheaper, more environmentally friendly, water-based alternative. A wide-ranging review was carried out to determine the most cost-effective options to obtain reservoir information. This included an examination of lithology, casing design, bit selection, hydraulics, logging requirements and techniques, and development of a suitable water-based mud. This holistic approach was seen as the most effective method of avoiding use of oil-based mud. After successful experimentation, a water-based mud was used in subsequent wells at Welton. A high-salt mud system and the drilling principles discussed here produced significant improvement in hole conditions. Application of a holistic approach led to many operational improvements. For instance, the casing shoe was deepened to case off the most troublesome zone in the local Edlington formation. There also was a better awareness of alternative logging techniques, the commercial factors that influenced their use and their operational and technical limitations. Logging problems were reduced but not eliminated. Where there were problems, application of improved techniques minimized their impact. Last, but not least, there was an unexpected spin-off in that the bit chosen to reduce hole erosion also reduced the time taken to drill the section

The largest glitch observed in the Crab pulsar

Science.gov (United States)

Shaw, B.; Lyne, A. G.; Stappers, B. W.; Weltevrede, P.; Bassa, C. G.; Lien, A. Y.; Mickaliger, M. B.; Breton, R. P.; Jordan, C. A.; Keith, M. J.; Krimm, H. A.

2018-05-01

We have observed a large glitch in the Crab pulsar (PSR B0531+21). The glitch occurred around MJD 58064 (2017 November 8) when the pulsar underwent an increase in the rotation rate of Δν = 1.530 × 10-5 Hz, corresponding to a fractional increase of Δν/ν = 0.516 × 10-6 making this event the largest glitch ever observed in this source. Due to our high-cadence and long-dwell time observations of the Crab pulsar we are able to partially resolve a fraction of the total spin-up of the star. This delayed spin-up occurred over a timescale of ˜1.7 days and is similar to the behaviour seen in the 1989 and 1996 large Crab pulsar glitches. The spin-down rate also increased at the glitch epoch by Δ \\dot{ν } / \\dot{ν } = 7 × 10^{-3}. In addition to being the largest such event observed in the Crab, the glitch occurred after the longest period of glitch inactivity since at least 1984 and we discuss a possible relationship between glitch size and waiting time. No changes to the shape of the pulse profile were observed near the glitch epoch at 610 MHz or 1520 MHz, nor did we identify any changes in the X-ray flux from the pulsar. The long-term recovery from the glitch continues to progress as \\dot{ν } slowly rises towards pre-glitch values. In line with other large Crab glitches, we expect there to be a persistent change to \\dot{ν }. We continue to monitor the long-term recovery with frequent, high quality observations.

Seafloor monitoring for synthetic-based mud discharged in the Western Gulf of Mexico

International Nuclear Information System (INIS)

Candler, J.E.; Hoskin, S.; Churan, M.

1995-01-01

Synthetic-based muds have been used to simultaneously improve drilling and environmental performance. The fate and effects of synthetic-based mud discharges in the marine environment have been issues of concern with the drilling industry and governmental agencies. Most of the environmental data on synthetic-based muds have been generated under laboratory conditions. This study uses field-collected data to investigate, the fate and effects of a polyalphaolefin synthetic-based drilling fluid. The first well drilled in the Gulf of Mexico using synthetic-based mud was completed in June 1992. Approximately 441 bbl of cuttings and 354 bbl of synthetic-based mud were discharged over a 9-day period. Three sampling trips have been made to the discharge location to collect sediment samples for chemical and biological analysis over a 2-year period. The sediment samples were analyzed for content of organic compounds and barium. On the third trip, infaunal samples were also taken. Information collected from the chemical and biological analysis is documented and compared to similar field studies performed on oil-based and water-based muds. Sampling techniques and analytical protocols are described to facilitate future studies. Two years after discharges of synthetic-based cuttings were completed, an area within 50 m of the discharge point continued to exhibit alterations in the benthic community not normally associated with water-based mud discharges. However, the study indicates that polyalphaolefin synthetic-based mud exhibits significant improvements over oil-based mud in terms of removal of organic contamination and minimization of adverse effects on the benthic community

The Crab nebula's ''wisps'' as shocked pulsar wind

International Nuclear Information System (INIS)

Gallant, Y.A.; Arons, J.; Langdon, A.B.

1992-01-01

The Crab synchrotron nebula has been successfully modelled as the post-shock region of a relativistic, magnetized wind carrying most of the spindown luminosity from the central pulsar. While the Crab is the best-studied example, most of the highest spindown luminosity pulsars are also surrounded by extended synchrotron nebulae, and several additional supernova remnants with ''plerionic'' morphologies similar to the Crab are known where the central object is not seen. All these objects have nonthermal, power-law spectra attributable to accelerated high-energy particles thought to originate in a Crab-like relativistic pulsar wind. However, proposed models have so far treated the wind shock as an infinitesimally thin discontinuity, with an arbitrarily ascribed particle acceleration efficiency. To make further progress, investigations resolving the shock structure seemed in order. Motivated by these considerations, we have performed ''particle-in-cell (PIC) simulations of perpendicularly magnetized shocks in electron-positron and electron-positron-ion plasmas. The shocks in pure electron-positron plasmas were found to produce only thermal distributions downstream, and are thus poor candidates as particle acceleration sites. When the upstream plasma flow also contained a smaller population of positive ions, however, efficient acceleration of positrons, and to a lesser extent of electrons, was observed in the simulations

A comparative study of mud-like and coralliform calcium carbonate gallbladder stones.

Science.gov (United States)

Ma, Rui-Hong; Luo, Xiao-Bing; Wang, Xiao-Feng; Qiao, Tie; Huang, Hai-Yi; Zhong, Hai-Qiang

2017-07-01

To gain insight to underlying mechanism of the formation of calcium carbonate (CaCO 3 ) gallbladder stones, we did comparative study of stones with mud appearance and those with coralliform appearance. A total of 93 gallbladder stones with mud appearance and 50 stones with coralliform appearance were analyzed. The appearance, color, texture, and the detection of Clonorchis sinensis eggs by microscopic examination were compared between the two groups. Then, the material compositions of stones were analyzed using Fourier Transform Infrared spectroscopy and the spectrogram characteristics were compared. Moreover, microstructure characteristics of the two kinds of stones were observed and compared with Scanning Electron Microscopy. Mud-like gallbladder stones were mainly earthy yellow or brown with brittle or soft texture, while coralliform stones were mainly black with extremely hard texture, the differences between the two groups was significant (p mud-like gallbladder stones were CaCO 3 stones, and mainly aragonite; while all of the coralliform stones were CaCO 3 stones, and mainly calcite (p mud-like CaCO 3 stones was lower than that in coralliform CaCO 3 stones (p Mud-like CaCO 3 stones mainly happened to patients with cystic duct obstruction. Clonorchis sinensis infection was mainly associated with coralliform (calcite) CaCO 3 stones. Cystic duct obstruction was mainly associated with mud-like (aragonite) CaCO 3 stones. © 2017 Wiley Periodicals, Inc.

Associations between dioxins/furans and dioxin-like PCBs in estuarine sediment and blue crab

Science.gov (United States)

Liebens, J.; Mohrherr, C.J.; Karouna-Renier, N. K.; Snyder, R.A.; Rao, K.R.

2011-01-01

The objective of the present study was to evaluate the relationships between the quantity, toxicity, and compositional profile of dioxin/furan compounds (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in estuarine sediment and in the blue crab (Callinectes sapidus). Sediment and blue crab samples were collected in three small urban estuaries that are in relatively close proximity to each other. Results show that differences between PCDD/F and DL-PCB mass concentrations and total toxic equivalents (TEQ) toxicity in sediments of the three estuaries are reflected in those of the blue crab. TEQs are higher in the hepatopancreas of the crabs than in the sediment, but the concentration factor is inversely proportional to the TEQ in the sediments. Congener profiles in the crabs are systematically different from those in the sediments, and the difference is more pronounced for PCDD/Fs than for DL-PCBs, possibly due to differences in metabolization rates. Compared with sediment profiles, more lesser-chlorinated PCDD/Fs that have higher TEFs accumulate in crab hepatopancreas. This selective bioaccumulation of PCDD/Fs results in a TEQ augmentation in crab hepatopancreas compared with sediments. The bioaccumulation in the blue crab is also selective for PCDD/Fs over DL-PCBs. ?? 2011 Springer Science+Business Media B.V.

Golden Crab Logbook Survey (Vessels)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — In November 1995, a voluntary logbook program for the golden crab fishery in the waters under the jurisdiction of the South Atlantic Fishery Management Council...

Mineralogical and geochemical study of mud volcanoes in north ...

African Journals Online (AJOL)

The gulf of Cadiz is one of the most interesting areas to study mud volcanoes and structures related to cold fluid seeps since their discovery in 1999. In this study, we present results from gravity cores collected from Ginsburg and Meknes mud volcanoes and from circular structure located in the gulf of Cadiz (North Atlantic ...

Edible crabs "go west": migrations and incubation cycle of Cancer pagurus revealed by electronic tags.

Directory of Open Access Journals (Sweden)

Ewan Hunter

Full Text Available Crustaceans are key components of marine ecosystems which, like other exploited marine taxa, show seasonable patterns of distribution and activity, with consequences for their availability to capture by targeted fisheries. Despite concerns over the sustainability of crab fisheries worldwide, difficulties in observing crabs' behaviour over their annual cycles, and the timings and durations of reproduction, remain poorly understood. From the release of 128 mature female edible crabs tagged with electronic data storage tags (DSTs, we demonstrate predominantly westward migration in the English Channel. Eastern Channel crabs migrated further than western Channel crabs, while crabs released outside the Channel showed little or no migration. Individual migrations were punctuated by a 7-month hiatus, when crabs remained stationary, coincident with the main period of crab spawning and egg incubation. Incubation commenced earlier in the west, from late October onwards, and brooding locations, determined using tidal geolocation, occurred throughout the species range. With an overall return rate of 34%, our results demonstrate that previous reluctance to tag crabs with relatively high-cost DSTs for fear of loss following moulting is unfounded, and that DSTs can generate precise information with regards life-history metrics that would be unachievable using other conventional means.

Preliminary study on domestication of coconut crab (Birgus latro

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. Sulistiono

2007-07-01

Full Text Available Preliminary study on domestication of coconut crab (Birgus latro had been done since June - November 2004 and December - 2005 February 2006.  Study was carried out in two locations namely Laboratory of Sekolah Tinggi Kelautan dan Perikanan, Palu to study adult crab, and Laboratory of Ecobiology of Faculty of Fisheries and Marine Science, Bogor Agricultural University to study crab in clomang stage.  Adult crabs were collected by using some fishing gears namely trap, net and directly using bamboo stick.  Domestication was done in rearing batch sized 1x1x1 m3 with artificial nests (30x15x15 cm3, and small batch for water (7x10x10 cm3.  While for clomang stage, crabs were reared in aquarium (80x40x40 cm3 with debris and small water batch.  Result showed that adult crab had a survival rate around 12.5-0%, and mortality around 50-87.5%.  A similar result was also in clomang stage, which was 12.5% for survival rate and 87.5% for mortality.  Adult coconut crab was preferred to feed coconut than other food likely vegetable and chick. Keywords: domestication, coconut crab, Birgus latro, food habit   ABSTRAK Penelitian awal mengenai kajian awal penangkaran kepiting kelapa (Birgus latro dilakukan pada bulan Juni - November 2004 dan Desember 2005 Februari 2006.  Pelaksanaan penelitian di lakukan di dua tempat, yaitu Laboratorium Sekolah Tinggi Kelautan dan Perikanan, Palu untuk percobaan kepiting dewasa, dan Laboratorium Ekobiologi Fakultas Perikanan dan Ilmu Kelautan IPB Bogor,  untuk percobaan kepiting tahap klomang.  Kepiting dewasa ditangkap dengan menggunakan beberapa peralatan a.l. perangkap, jaring dan secara langsung dengan tongkat.  Penangkaran dilakukan di bak-bak peliharaan berukuran 1x1x1 m3 yang dilengkapi dengan tempat persembunyian (30x15x15 cm3, dan bak kecil tempat air (7x10x10 cm3.  Sedangkan kepiting tahap klomang dipelihara di akuarium (80x40x40 cm3 yang diberi daun/serasah dan tempat air.  Hasil uji coba penangkaran

Inactivation of Paragonimus westermani metacercariae in soy sauce-marinated and frozen freshwater crabs.

Science.gov (United States)

Kim, Tae Im; Oh, Se-Ra; Dai, Fuhong; Yang, Hyun-Jong; Ha, Sang-Do; Hong, Sung-Jong

2017-03-01

Soy sauce-marinated freshwater crabs (Eriocheir japonicus) are a source of human paragonimiasis. The viability of Paragonimus westermani metacercariae (PwMc) in marinated crabs was investigated in an experimental setting. The PwMc collected from freshwater crayfish were inoculated into freshwater crabs, which were then frozen or marinated in soy sauce. All PwMc in the freshwater crabs were inactivated after freezing for 48 h at -20 °C and after freezing for 12 h at -40 °C. After marinating for 32 days, the survival rate of PwMc in 5% NaCl soy sauce was 50%, in 7.5% NaCl soy sauce it was 33.3%, and in 10.0% NaCl soy sauce it was 31.3%. When marinated for 64 days, all PwMc were inactivated in all experimental groups. These results revealed that freezing and soy sauce marination were detrimental to the survival of PwMc in freshwater crabs. Specifically, freezing crabs for more than 48 h or soaking them in soy sauce containing at least 5.0% NaCl for 64 days can inactivate PwMc. These results can inform the production of the traditional Korean soy sauce-marinated freshwater crabs known as gejang.

CRABS IN CRISIS:BIOGEOGRAPHIC DISTRIBUTIONS, ABUNDANCES, AND VULNERABILITIES TO CLIMATE CHANGE OF BRACHYURAN AND LITHODID CRABS FROM THE GULF OF CALIFORNIA TO THE BEAUFORT SEA

Science.gov (United States)

To predict the relative vulnerability of near-coastal species to climate change we analyzed the biogeographic and abundance patterns of the brachyuran or ‘True’ crabs (n=368) and lithodid or ‘King’ crabs (n=20) that are found in the twelve MEOW (“Mar...

Using ssh as portal - The CMS CRAB over glideinWMS experience

CERN Document Server

Belforte, Stefano; Letts, James; Fanzago, Federica; Saiz Santos, Maria Dolores; Martin, Terrence

2013-01-01

The User Analysis of the CMS experiment is performed in distributed way usingboth Grid and dedicated resources. In order to insulate the users from the details of computing fabric, CMS relies on the CRAB (CMS Remote Analysis Builder) package as an abstraction layer. CMS has recently switched from a client-server version of CRAB to a purely client-based solution, with ssh being used to interface with HTCondor-based glideinWMS batch system. This switch has resulted in significant improvement of user satisfaction, as well as in significant simplification of the CRAB code base and of the operation support. This paper presents the architecture of the ssh-based CRAB package, the rationale behind it, as well as the operational experience running both the client-server and the ssh-based versions in parallel forseveral months.

HEAVY METALS IN SURFACE MUD SEDIMENT IN EKATERINBURG (RUSSIA

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A. A. Seleznev

2018-03-01

Full Text Available Problem Statement. Now the most part of the world’s population lives in cities, thus, it is relevant the search for universal, low-cost and express methods for environmental geochemical investigations of an urban environment. The objective of the study is the assessment of content and properties of surface mud sediment at the urban territory (on the example of Ekaterinburg, Russia. Methods of the study. The 30 samples of surface mud sediment, soils and ground were collected in the residential area of the city. Particle size composition, measurements of heavy metals content, correlation analysis was conducted for the samples. Results. Surface mud sediment at the residential territories can be classified as surface facie of the recent anthropogenic sediment. Samples of the environmental compartments were collected at the territories of six blocks of houses of various years of construction, located in various parts of the city and at the various geological units. Five samples were collected in each block: 3 samples within the block and 2 samples – outside. The content of Pb, Zn, Cu, Ni, Co, and Mn was measured in particle size fractions of the samples. Particle size composition of the surface mud sediment in Ekaterinburg is similar to the particle size composition of the grounds formed on the sediments of Holocene age in Urals region. The positive statistically significant correlation was found between the couples of metals: Zn and Pb, Zn and Cu, Co and Ni. The distribution of concentrations of Pb, Zn and Cu over particle size fractions of surface mud sediment is heterogeneous. Pollution of the ground and soil in urban areas is due to the transition of heavy metals with particles of dust and fine sand. Typical geochemical association of metals for particle size fraction of surface mud sediment 0.002–0.01 mm – Mn-Zn-Ni-Cu-Pb-Co, that is similar to the association for sediments of surface puddles in local zones of relief, soils and bottom

Experimental study and mechanism analysis of modified limestone by red mud for improving desulfurization

Energy Technology Data Exchange (ETDEWEB)

Liu, Hongtao; Han, Kuihua; Niu, Shengli; Lu, Chunmei; Liu, Mengqi; Li, Hui [Shandong Univ., Jinan (China). School of Energy and Power Engineering

2013-07-01

Red mud is a type of solid waste generated during alumina production from bauxite, and how to dispose and utilize red mud in a large scale is yet a question with no satisfied answer. This paper attempts to use red mud as a kind of additive to modify the limestone. The enhancement of the sulfation reaction of limestone by red mud (two kinds of Bayer process red mud and one kind of sintering process red mud) are studied by a tube furnace reactor. The calcination and sulfation process and kinetics are investigated in a thermogravimetric (TG) analyzer. The results show that red mud can effectively improve the desulfurization performance of limestone in the whole temperature range (1,073-1,373K). Sulfur capacity of limestone (means quality of SO{sub 2} which can be retained by 100mg of limestone) can be increased by 25.73, 7.17 and 15.31% while the utilization of calcium can be increased from 39.68 to 64.13%, 60.61 and 61.16% after modified by three kinds of red mud under calcium/metallic element (metallic element described here means all metallic elements which can play a catalytic effect on the sulfation process, including the Na, K, Fe, Ti) ratio being 15, at the temperature of 1,173K. The structure of limestone modified by red mud is interlaced and tridimensional which is conducive to the sulfation reaction. The phase composition analysis measured by XRD of modified limestone sulfated at high temperature shows that there are correspondingly more sulphates for silicate and aluminate complexes of calcium existing in the products. Temperature, calcium/metallic element ratio and particle diameter are important factors as for the sulfation reaction. The optimum results can be obtained as calcium/metallic element ratio being 15. Calcination characteristic of limestone modified by red mud shows a migration to lower temperature direction. The enhancement of sulfation by doping red mud is more pronounced once the product layer has been formed and consequently the promoting

Beam dynamics aspects of crab cavities in the CERN Large Hadron Collider

CERN Document Server

Sun, Y P; Barranco, J; Tomás, R; Weiler, T; Zimmermann, F; Calaga, R; Morita, A

2009-01-01

Modern colliders bring into collision a large number of bunches to achieve a high luminosity. The long-range beam-beam effects arising from parasitic encounters at such colliders are mitigated by introducing a crossing angle. Under these conditions, crab cavities (CC) can be used to restore effective head-on collisions and thereby to increase the geometric luminosity. Such crab cavities have been proposed for both linear and circular colliders. The crab cavities are rf cavities operated in a transverse dipole mode, which imparts on the beam particles a transverse kick that varies with the longitudinal position along the bunch. The use of crab cavities in the Large Hadron Collider (LHC) may not only raise the luminosity, but it could also complicate the beam dynamics, e.g., crab cavities might not only cancel synchrobetatron resonances excited by the crossing angle but they could also excite new ones, they could reduce the dynamic aperture for off-momentum particles, they could influence the aperture and orbit...

Behavioral thermoregulation in Hemigrapsus nudus, the amphibious purple shore crab.

Science.gov (United States)

McGaw, I J

2003-02-01

The thermoregulatory behavior of Hemigrapsus nudus, the amphibious purple shore crab, was examined in both aquatic and aerial environments. Crabs warmed and cooled more rapidly in water than in air. Acclimation in water of 16 degrees C (summer temperatures) raised the critical thermal maximum temperature (CTMax); acclimation in water of 10 degrees C (winter temperatures) lowered the critical thermal minimum temperature (CTMin). The changes occurred in both water and air. However, these survival regimes did not reflect the thermal preferences of the animals. In water, the thermal preference of crabs acclimated to 16 degrees C was 14.6 degrees C, and they avoided water warmer than 25.5 degrees C. These values were significantly lower than those of the crabs acclimated to 10 degrees C; these animals demonstrated temperature preferences for water that was 17 degrees C, and they avoided water that was warmer than 26.9 degrees C. This temperature preference was also exhibited in air, where 10 degrees C acclimated crabs exited from under rocks at a temperature that was 3.2 degrees C higher than that at which the 16 degrees C acclimated animals responded. This behavioral pattern was possibly due to a decreased thermal tolerance of 16 degrees C acclimated crabs, related with the molting process. H. nudus was better able to survive prolonged exposure to cold temperatures than to warm temperatures, and there was a trend towards lower exit temperatures with the lower acclimation (10 degrees C) temperature. Using a complex series of behaviors, the crabs were able to precisely control body temperature independent of the medium, by shuttling between air and water. The time spent in either air or water was influenced more strongly by the temperature than by the medium. In the field, this species may experience ranges in temperatures of up to 20 degrees C; however, it is able to utilize thermal microhabitats underneath rocks to maintain its body temperature within fairly narrow

Space Movie Reveals Shocking Secrets Of The Crab Pulsa

Science.gov (United States)

2002-09-01

Just when it seemed like the summer movie season had ended, two of NASA's Great Observatories have produced their own action movie. Multiple observations made over several months with NASA's Chandra X-ray Observatory and the Hubble Space Telescope captured the spectacle of matter and antimatter propelled to near the speed of light by the Crab pulsar, a rapidly rotating neutron star the size of Manhattan. "Through this movie, the Crab Nebula has come to life," said Jeff Hester of Arizona State University in Tempe, lead author of a paper in the September 20th issue of The Astrophysical Journal Letters. "We can see how this awesome cosmic generator actually works." The Crab was first observed by Chinese astronomers in 1054 A.D. and has since become one of the most studied objects in the sky. By combining the power of both Chandra and Hubble, the movie reveals features never seen in still images. By understanding the Crab, astronomers hope to unlock the secrets of how similar objects across the universe are powered. Crab Nebula Composite Image Crab Nebula Composite Image Bright wisps can be seen moving outward at half the speed of light to form an expanding ring that is visible in both X-ray and optical images. These wisps appear to originate from a shock wave that shows up as an inner X-ray ring. This ring consists of about two dozen knots that form, brighten and fade, jitter around, and occasionally undergo outbursts that give rise to expanding clouds of particles, but remain in roughly the same location. "These data leave little doubt that the inner X-ray ring is the location of the shock wave that turns the high-speed wind from the pulsar into extremely energetic particles," said Koji Mori of Penn State University in University Park, a coauthor of the paper. Another dramatic feature of the movie is a turbulent jet that lies perpendicular to the inner and outer rings. Violent internal motions are obvious, as is a slow motion outward into the surrounding nebula of

Effect of mangrove restoration on crab burrow density in Luoyangjiang Estuary, China

Directory of Open Access Journals (Sweden)

Wei Li

2015-07-01

Full Text Available Background Mangrove restoration seeks to restore or rebuild degraded mangrove systems. The methods of mangrove restoration include ecological projects and restoration-oriented technologies, the latter of which are designed to restore the structure, processes as well as related physical, chemical and biological characteristics of wetlands and to ensure the provision of ecosystem services. As important components of mangrove ecosystem, benthic organisms and crabs play a key role in nutrient cycling. In addition, mangrove restoration, such as vegetation restoration measures, can lead to changes in the benthic faunal communities. This study investigates whether the presence of different mangrove species, age and canopy cover of mangrove communities affect the density of crab burrows. Methods The Luoyangjiang Estuary, in the southeast of Fujian Province, was selected as our research area. A survey, covering 14 sites, was conducted to investigate the impacts of mangrove restoration on the density of crab burrows in four rehabilitated forests with different stand ages and canopy. Results It was found that differences in vegetation types had a large impact on crab density and that the density of crab burrows was lower on exposed beaches (non-mangrove than under mature Kandelia candel, Aegiceras corniculatum and Avicennia marina communities. In general, the amount of leaf litter and debris on mangrove mudflats was greater than on the beaches as food sources for crabs. Two-factor analysis of variance (ANOVA shows that changes in mangrove species and age since restoration had different effects on crab burrow density. The effect of canopy cover was highly significant on crab burrow density. Conclusions The results suggest that in the process of mangrove restoration the combined effects of mangrove stand age, canopy cover and other factors should be taken into account. This study further supports the findings of the future scientific research and practice on

Valorization of mud from Fergoug dam in manufacturing mortars

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L. Laoufi

2016-12-01

Full Text Available The production of calcined mud, with pozzolanic properties, from the large quantities of sediments dredged from Algerian dams, could be a good opportunity for the formulation of high performance mortars and pozzolanic concretes, with lower costs and less greenhouse gas (CO2 emissions. The optimal temperatures selected for calcination were 750, 850 and 950 °C. The burning operation was continuous over a period of 3 h. Therefore, a series of physical, chemical, mechanical and microstructural analyses were conducted on sediment samples, collected from the waters of Fergoug dam. The results obtained from the analyses of the calcined mud, from the dam, allowed saying that mortars with different percentages of that mud represent a potential source of high reactivity pozzolanic materials.

CMS distributed data analysis with CRAB3

Science.gov (United States)

Mascheroni, M.; Balcas, J.; Belforte, S.; Bockelman, B. P.; Hernandez, J. M.; Ciangottini, D.; Konstantinov, P. B.; Silva, J. M. D.; Ali, M. A. B. M.; Melo, A. M.; Riahi, H.; Tanasijczuk, A. J.; Yusli, M. N. B.; Wolf, M.; Woodard, A. E.; Vaandering, E.

2015-12-01

The CMS Remote Analysis Builder (CRAB) is a distributed workflow management tool which facilitates analysis tasks by isolating users from the technical details of the Grid infrastructure. Throughout LHC Run 1, CRAB has been successfully employed by an average of 350 distinct users each week executing about 200,000 jobs per day. CRAB has been significantly upgraded in order to face the new challenges posed by LHC Run 2. Components of the new system include 1) a lightweight client, 2) a central primary server which communicates with the clients through a REST interface, 3) secondary servers which manage user analysis tasks and submit jobs to the CMS resource provisioning system, and 4) a central service to asynchronously move user data from temporary storage in the execution site to the desired storage location. The new system improves the robustness, scalability and sustainability of the service. Here we provide an overview of the new system, operation, and user support, report on its current status, and identify lessons learned from the commissioning phase and production roll-out.

Warts phosphorylates mud to promote pins-mediated mitotic spindle orientation in Drosophila, independent of Yorkie.

Science.gov (United States)

Dewey, Evan B; Sanchez, Desiree; Johnston, Christopher A

2015-11-02

Multicellular animals have evolved conserved signaling pathways that translate cell polarity cues into mitotic spindle positioning to control the orientation of cell division within complex tissue structures. These oriented cell divisions are essential for the development of cell diversity and the maintenance of tissue homeostasis. Despite intense efforts, the molecular mechanisms that control spindle orientation remain incompletely defined. Here, we describe a role for the Hippo (Hpo) kinase complex in promoting Partner of Inscuteable (Pins)-mediated spindle orientation. Knockdown of Hpo, Salvador (Sav), or Warts (Wts) each result in a partial loss of spindle orientation, a phenotype previously described following loss of the Pins-binding protein Mushroom body defect (Mud). Similar to orthologs spanning yeast to mammals, Wts kinase localizes to mitotic spindle poles, a prominent site of Mud localization. Wts directly phosphorylates Mud in vitro within its C-terminal coiled-coil domain. This Mud coiled-coil domain directly binds the adjacent Pins-binding domain to dampen the Pins/Mud interaction, and Wts-mediated phosphorylation uncouples this intramolecular Mud interaction. Loss of Wts prevents cortical Pins/Mud association without affecting Mud accumulation at spindle poles, suggesting phosphorylation acts as a molecular switch to specifically activate cortical Mud function. Finally, loss of Wts in Drosophila imaginal disc epithelial cells results in diminished cortical Mud and defective planar spindle orientation. Our results provide new insights into the molecular basis for dynamic regulation of the cortical Pins/Mud spindle positioning complex and highlight a novel link with an essential, evolutionarily conserved cell proliferation pathway. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ocean Acidification Affects Hemocyte Physiology in the Tanner Crab (Chionoecetes bairdi)

Science.gov (United States)

Meseck, Shannon L.; Alix, Jennifer H.; Swiney, Katherine M.; Long, W. Christopher; Wikfors, Gary H.; Foy, Robert J.

2016-01-01

We used flow cytometry to determine if there would be a difference in hematology, selected immune functions, and hemocyte pH (pHi), under two different, future ocean acidification scenarios (pH = 7.50, 7.80) compared to current conditions (pH = 8.09) for Chionoecetes bairdi, Tanner crab. Hemocytes were analyzed after adult Tanner crabs were held for two years under continuous exposure to acidified ocean water. Total counts of hemocytes did not vary among control and experimental treatments; however, there were significantly greater number of dead, circulating hemocytes in crabs held at the lowest pH treatment. Phagocytosis of fluorescent microbeads by hemocytes was greatest at the lowest pH treatment. These results suggest that hemocytes were dying, likely by apoptosis, at a rate faster than upregulated phagocytosis was able to remove moribund cells from circulation at the lowest pH. Crab hemolymph pH (pHe) averaged 8.09 and did not vary among pH treatments. There was no significant difference in internal pH (pHi) within hyalinocytes among pH treatments and the mean pHi (7.26) was lower than the mean pHe. In contrast, there were significant differences among treatments in pHi of the semi-granular+granular cells. Control crabs had the highest mean semi-granular+granular pHi compared to the lowest pH treatment. As physiological hemocyte functions changed from ambient conditions, interactions with the number of eggs in the second clutch, percentage of viable eggs, and calcium concentration in the adult crab shell was observed. This suggested that the energetic costs of responding to ocean acidification and maintaining defense mechanisms in Tanner crab may divert energy from other physiological processes, such as reproduction. PMID:26859148

Provenance discrimination of sediments in the Zhejiang-Fujian mud belt, East China Sea: Implications for the development of the mud depocenter

Science.gov (United States)

Liu, Xiting; Li, Anchun; Dong, Jiang; Lu, Jian; Huang, Jie; Wan, Shiming

2018-01-01

In the past decade, the 800 km elongated mud belt off Zhejiang-Fujian coast, East China Sea (ECS), has been extensively studied for understanding the source to sink processes on the East Asian continental margin in the context of the Asian monsoon. However, to better understand the sediment source and dispersal pattern, the existing mineralogical and geochemical data of adjacent river systems, including the Changjiang River (CJR) and local rivers in Zhejiang, Fujian and Taiwan, need to be systematically reviewed. Therefore, various indicators from published literatures for the provenance discrimination in the mud belt have been summarised in this article. The results show that high diversity of clay mineral assemblages in fluvial sediments being supplied into the mud belt, e.g., dominant illite and chlorite in the CJR, absence of smectite in Taiwan rivers, similar amounts of the four clay mineral species in Zhejiang rivers, and dominant kaolinite in Fujian rivers. On heavy mineralogy, the CJR is dominated by dolomite, hornblende, and flaky minerals; and among of them, dolomite is distinctive for the CJR. For geochemical approaches, elemental compositions, combined with strontium and neodymium isotopes, reflect strong provenance control. However, geochemical and mineralogical compositions are found to vary with grain size, and thus extra caution should be taken when using these parameters as provenance indicator to discriminate the marine sediments with variety of grain-size fractions. In addition, pyrrhotite, occurred in fluvial sediments from western Taiwan, has not been found in sediments derived from mainland China, indicating that magnetic parameters could be used to discriminate sediment provenance. The mud belt formed during sea-level highstand, when modern current system in the ECS has been established, resulting in sediments derived from the CJR have been transported southward since 8 ka. In addition, sediment provenances have not been constant since

Mud Pit Risk-Based Closure Strategy Report, Nevada Test Site, Nevada, Revision 0

Energy Technology Data Exchange (ETDEWEB)

Brain Hoenes

2004-08-01

This report presents the findings of the human and ecological risk assessment for the NTS mud pits. The risk assessment utilizes data from 52 of the 270 NTS mud pits in conjunction with corroborative data from 87 other DOE mud pits associated with nuclear testing (at locations on the NTS, in the western United States, and Alaska) as well as relevant process knowledge. Based on the risk assessment findings, the report provides a strategy for further evaluation, characterization, and closure of all 270 NTS mud pit CASs using the Streamlined Approach for Environmental Restoration (SAFER).

Implementation of viscoelastic mud-induced energy attenuation in the third-generation wave model, SWAN

Science.gov (United States)

Beyramzade, Mostafa; Siadatmousavi, Seyed Mostafa

2018-01-01

The interaction of waves with fluid mud can dissipate the wave energy significantly over few wavelengths. In this study, the third-generation wave model, SWAN, was advanced to include attenuation of wave energy due to interaction with a viscoelastic fluid mud layer. The performances of implemented viscoelastic models were verified against an analytical solution and viscous formulations for simple one-dimensional propagation cases. Stationary and non-stationary test cases in the Surinam coast and the Atchafalaya Shelf showed that the inclusion of the mud-wave interaction term in the third-generation wave model enhances the model performance in real applications. A high value of mud viscosity (of the order of 0.1 m2/s) was required in both field cases to remedy model overestimation at high frequency ranges of the wave spectrum. The use of frequency-dependent mud viscosity value improved the performance of model, especially in the frequency range of 0.2-0.35 Hz in the wave spectrum. In addition, the mud-wave interaction might affect the high frequency part of the spectrum, and this part of the wave spectrum is also affected by energy transfer from wind to waves, even for the fetch lengths of the order of 10 km. It is shown that exclusion of the wind input term in such cases might result in different values for parameters of mud layer when inverse modeling procedure was employed. Unlike viscous models for wave-mud interaction, the inverse modeling results to a set of mud parameters with the same performance when the viscoelastic model is used. It provides an opportunity to select realistic mud parameters which are in more agreement with in situ measurements.

AFSC/RACE/SAP/Long: Data from: Effects of Ocean Acidification on Juvenile Red King Crab (Paralithodes camtschaticus) and Tanner Crab (Chionoecetes bairdi) Growth, Condition, Calcification, and Survival

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set is the results of a laboratory experiment. Juvenile red king crab and Tanner crab were reared in individual containers for nearly 200 days in flowing...

Snow crab allergy and asthma among Greenlandic workers – a pilot study

Directory of Open Access Journals (Sweden)

Jakob Hjort Bønløkke

2012-08-01

Full Text Available Objectives. To study snow crab sensitization, occupational allergy and asthma in the snow crab industry in Greenland, as high rates have been found in Canada, but no reports have emerged from the same industry in Greenland. Study design. Pilot survey. Methods. Twenty workers (19 of Inuit and 1 of other origin in a snow crab (Chionoecetes opilio and Atlantic shrimp (Pandalus borealis processing plant in Greenland were assessed with skin prick tests (SPTs with common aeroallergens and specific allergens from snow crab and shrimp extracts, spirometry, blood sampling for total IgE and specific IgE determination. Eighteen workers contributed a questionnaire-based medical interview. Results. Positive skin prick test reactions were common to snow crab (40% and shrimp (20%. Specific IgE to snow crab were positive in 4 workers (21%. Two workers had elevated total IgE levels. Symptoms suggestive of asthma were common (45%. Work-related symptoms of skin rash, rhinitis, and/or conjunctivitis were reported by 50%, and symptoms from the lower airways by 39%. Combining history of work-related symptoms with results from specific SPTs and/or specific IgE determination suggested that 11 and 22% of workers suffered from probable and possible occupational asthma, respectively, whereas 22% had possible occupational dermatitis or rhinitis. Conclusions. Greenlander Inuit do not appear to be protected against sensitization to snow crab or shrimp when occupationally exposed to these. This pilot study suggests that occupational allergy and asthma may be as common a problem in Greenlandic workers as in Canadian.

Rheological measurements on artifical muds

NARCIS (Netherlands)

De Wit, P.J.

1992-01-01

The rheological behaviour of three artificial muds was determined using a rotational viscometer. First some characteristics of the viscometer used were rneasured. For want of an appropriate calibration tluid, the viscosity of demineralized water was determined. The result agreed very well with what

75 FR 56485 - Groundfish Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea/Aleutian Islands Crab...

Science.gov (United States)

2010-09-16

.../Aleutian Islands Crab Rationalization Program; Recordkeeping and Reporting AGENCY: National Marine... rule. SUMMARY: NMFS issues regulations to remove the Crab Rationalization Program requirements for.... Background The Crab Rationalization (CR) Program is a limited-access system that allocates crab managed under...

Arsenobetaine in the red crab, Chionoecetes opilio

Energy Technology Data Exchange (ETDEWEB)

Matsuto, S.; Stockton, R.A.; Irgolic, K.J.

1986-01-01

The meat of the red crab, Chionoecetes opilio, caught near the central coast the Japan Sea, was extracted with methanol. The arsenic compounds were isolated from this extract and purified by anion and cation exchange chromatography and thin-layer chromatography. Three arsenic compounds were detected. The major arsenic compound, identified as arsenobetaine by TLC, proton NMR spectroscopy, and high pressure liquid chromatography with an atomic absorption spectrometer as an arsenic-specific detector, accounted for 90% of the total arsenic in the crab meat. The other two arsenic compounds could not be identified because of insufficient amounts available for analysis.

Morphodynamic Modeling of Tidal Mud Flats

National Research Council Canada - National Science Library

Winterwerp, Johan C

2008-01-01

The objective of the current research proposal is to develop and test a numerical model to simulate and predict the seasonal morphodynamic evolution of intertidal mud flats in macrotidal environments...

Effect of strong acids on red mud structural and fluoride adsorption properties.

Science.gov (United States)

Liang, Wentao; Couperthwaite, Sara J; Kaur, Gurkiran; Yan, Cheng; Johnstone, Dean W; Millar, Graeme J

2014-06-01

The removal of fluoride using red mud has been improved by acidifying red mud with hydrochloric, nitric and sulphuric acid. The acidification of red mud causes sodalite and cancrinite phases to dissociate, confirmed by the release of sodium and aluminium into solution as well as the disappearance of sodalite bands and peaks in infrared and X-ray diffraction data. The dissolution of these mineral phases increases the amount of available iron and aluminium oxide/hydroxide sites that are accessible for the adsorption of fluoride. However, concentrated acids have a negative effect on adsorption due to the dissolution of these iron and aluminium oxide/hydroxide sites. The removal of fluoride is dependent on the charge of iron and aluminium oxide/hydroxides on the surface of red mud. Acidifying red mud with hydrochloric, nitric and sulphuric acid resulted in surface sites of the form ≡SOH2(+) and ≡SOH. Optimum removal is obtained when the majority of surface sites are in the form ≡SOH2(+) as the substitution of a fluoride ion does not cause a significant increase in pH. This investigation shows the importance of having a low and consistent pH for the removal of fluoride from aqueous solutions using red mud. Copyright © 2014 Elsevier Inc. All rights reserved.

76 FR 35772 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab...

Science.gov (United States)

2011-06-20

... Aleutian Islands Crab Rationalization Program AGENCY: National Marine Fisheries Service (NMFS), National... Tanner Crabs. Amendment 34 amends the Bering Sea and Aleutian Islands Crab Rationalization Program to... for the Crab Rationalization Program are available from the NMFS Alaska Region Web site at http...

Electrical resistivity and rheological properties of sensing bentonite drilling muds modified with lightweight polymer

Directory of Open Access Journals (Sweden)

Ahmed S. Mohammed

2018-03-01

Full Text Available In this study, the electrical resistivity and rheological properties of a water-based bentonite clay drilling mud modified with the lightweight polymer (guar gum under various temperature were investigated. Based on the experimental and analytical study, the electrical resistivity was identified as the sensing property of the bentonite drilling mud so that the changes in the properties can be monitored in real-time during the construction. The bentonite contents in the drilling muds were varied up to 8% by the weight of water and temperature was varied from 25 °C to 85 °C. The guar gum content (GG% was varied between 0% and 1% by the weight of the drilling mud to modify the rheological properties and enhance the sensing electrical resistivity of the drilling mud. The guar gum and bentonite clay were characterized using thermal gravimetric analysis (TGA. The total weight loss at 800 °C for the bentonite decreased from 12.96% to 0.7%, about 95% reduction, when the bentonite was mixed with 1% of guar gum. The results also showed that 1% guar gum decreased the electrical resistivity of the drilling mud from 50% to 90% based on the bentonite content and the temperature of the drilling mud. The guar gum modification increased the yield point (YP and plastic viscosity (PV by 58% to 230% and 44% to 77% respectively based on the bentonite content and temperature of the drilling mud. The rheological properties of the drilling muds have been correlated to the electrical resistivity of the drilling mud using nonlinear power and hyperbolic relationships. The model predictions agreed well with the experimental results. Hence the performance of the bentonite drilling muds with and without guar gum can be characterized based on the electrical resistivity which can be monitored real-time in the field. Keywords: Bentonite, Polymer (Guar gum, Electrical resistivity, Rheological properties, Temperature, Modeling

Analysis of chloride diffusivity in concrete containing red mud

Directory of Open Access Journals (Sweden)

D.V. Ribeiro

Full Text Available Red mud is a solid waste produced in the alumina production process and, due to its high pH, is classified as hazardous. Its incorporation in concrete mixtures, acting as filler due to the particles fineness, might be an interesting reuse alternative. The focus of this paper is to study the chloride diffusivity of concrete mixtures containing red-mud. The concentration of chlorides was monitored by measuring the conductivity of the anolyte, which was distilled water initially. In addition, the estimation of the chloride ions diffusion coefficients in steady and non-steady conditions, Ds and Dns, was obtained from the ''time-lag'' and ''equivalent time'' between diffusion and migration experiments. Due to superfine particle-size distribution and the "filler" effect, the red mud addition seems to assure lower chloride diffusivity.

A Comparative SEM-EDS Elemental Composition of Mud in Coastal ...

African Journals Online (AJOL)

The present study was aimed to understand the comparative abundance and source of elemental constituents in mud of four coastal shrimp farming areas, Vunh Tau (VT), Nha Trang (NT), Da Nang (DN) and Hue (HU) in Viet Nam using SEM-EDS analysis. Mud samples were collected from shrimp farming coastal zones ...

Use of clay-free polymer saline drilling muds. Primeneniye bezglinistykh polimerosolevykh burovykh rastvorov

Energy Technology Data Exchange (ETDEWEB)

Krysin, N I; Ishmukhametova, A M; Krysina, T I; Mavlyutov, M R

1982-01-01

A brief analysis is made of the geological and technical and technological conditions for drilling and stripping productive beds in the Perm Prikamye. Domestic and foreign experience in the area of studies covering the effect of properties of the drilling muds on the indicators of operation of bits and preservation of stability of the well shaft walls, as well as for development of formulas for clay-free drilling muds is generalized. Results are presented of studies on viscosity and filtering properties of drilling muds, development of clay-free drilling muds based on potassium containing wastes and bed waters.

76 FR 35781 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab...

Science.gov (United States)

2011-06-20

... Aleutian Islands Crab Rationalization Program; Amendment 37 AGENCY: National Marine Fisheries Service (NMFS... Tanner Crabs (FMP). This action amends the Bering Sea/Aleutian Islands Crab Rationalization Program by... Assessment prepared for the Crab Rationalization Program are available from the NMFS Alaska Region Web site...

76 FR 47155 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab...

Science.gov (United States)

2011-08-04

... the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab Rationalization Program... program for the Bering Sea/Aleutian Islands crab fisheries managed under the BSAI Crab Rationalization... Center Web site at http://www.afsc.noaa.gov/ . For further information on the Crab Rationalization...

Mud Banks along the southwest coast of India are not too muddy for plankton.

Science.gov (United States)

Jyothibabu, R; Balachandran, K K; Jagadeesan, L; Karnan, C; Arunpandi, N; Naqvi, S W A; Pandiyarajan, R S

2018-02-07

Considering Alappuzha Mud Bank in the southern Kerala coast as a typical case of biologically productive Mud Banks that form along the southwest coast of India during the Southwest Monsoon (June - September), the present study addresses several pertinent missing links between the physical environment in Mud Banks and their influence on plankton stock. This study showed that very strong coastal upwelling prevails in the entire study domain during the Southwest Monsoon, which manifests itself in the form of significantly cool, hypoxic and nitrate-rich waters surfacing near the coast. The upwelled water persisting throughout the Southwest Monsoon period was found to have fuelled the exceptionally high phytoplankton stock in the entire study area, including the Mud Bank region. Having accepted that Mud Banks are special because of the calm sea surface conditions and relatively high turbidity level in the water column around them, the present study showed that except at points close to the sea bottom, turbidity level in the Alappuzha Mud Bank was below the critical level to inhibit the plankton stock. The suspended sediments that form in the Mud Bank occasionally could be attributed to the disturbance of the bottom fluid muddy layer and their vertical spurts.

Propagation of Measurement-While-Drilling Mud Pulse during High Temperature Deep Well Drilling Operations

Directory of Open Access Journals (Sweden)

Hongtao Li

2013-01-01

Full Text Available Signal attenuates while Measurement-While-Drilling (MWD mud pulse is transmited in drill string during high temperature deep well drilling. In this work, an analytical model for the propagation of mud pulse was presented. The model consists of continuity, momentum, and state equations with analytical solutions based on the linear perturbation analysis. The model can predict the wave speed and attenuation coefficient of mud pulse. The calculated results were compared with the experimental data showing a good agreement. Effects of the angular frequency, static velocity, mud viscosity, and mud density behavior on speed and attenuation coefficients were included in this paper. Simulated results indicate that the effects of angular frequency, static velocity, and mud viscosity are important, and lower frequency, viscosity, and static velocity benefit the transmission of mud pulse. Influenced by density behavior, the speed and attenuation coefficients in drill string are seen to have different values with respect to well depth. For different circulation times, the profiles of speed and attenuation coefficients behave distinctly different especially in lower section. In general, the effects of variables above on speed are seen to be small in comparison.

Plugging wellbore fractures : limit equilibrium of a Bingham drilling mud cake in a tensile crack

Energy Technology Data Exchange (ETDEWEB)

Garagash, D.I. [Dalhousie Univ., Halifax, NS (Canada). Dept. of Civil and Resource Engineering

2009-07-01

The proper selection of drilling muds is important in order to successfully drill hydrocarbon wells in which wellbore mud pressure remains low enough to prevent circulation loss and high enough to support the uncased wellbore against the shear failure. This paper presented a mathematical model to study invasion of mud cake into a drilling-induced planar fracture at the edge of a wellbore perpendicular to the minimum in situ principal stress. The model assumed a planar edge-crack geometry loaded by the wellbore hoop stress, variable mud pressure along the invaded region adjacent to the wellbore, and uniform pore-fluid pressure along the rest of the crack. The invading mud was assumed to freely displaces the pore-fluid in the crack without mixing with it. The case corresponding to a sufficiently permeable formation was considered. This solution provides a means to evaluate whether or not the mud cake could effectively plug the fracture, thereby prevent fracture propagation and associated uncontrollable loss of wellbore drilling mud. The toughness or tensile strength is evaluated based on criterion for initiation of crack propagation, which may lead to uncontrollable loss of mud circulation in a well. The study provided information on the breakdown pressure as a function of the rock ambient stress, ambient pore pressure, pre-existing crack length, and mud cake properties. 12 refs., 6 figs.

Endogenous cellulase production in the leaf litter foraging mangrove crab Parasesarma erythodactyla.

Science.gov (United States)

Bui, T H Hanh; Lee, Shing Yip

2015-01-01

The sesarmid crab Parasesarma erythodactyla consumes large amounts of mangrove leaf litter but its biochemical capacity for cellulose digestion is poorly known. We demonstrate the presence of endo-β-1,4-glucanase, β-glucosidase and total cellulase activities in the digestive juice of this crab. The highest total cellulase activity was observed at mildly acidic pH (5 to 6) and temperature between 30 and 50°C. A 1752bp cDNA containing an open reading frame of 1386bp encoding a putative endo-β-1,4-glucanase (EG) of 461 amino acids was identified in the crab's hepatopancreas using polymerase chain reaction (PCR), cloning and sequencing techniques. P. erythodactyla endo-β-1,4-glucanase (PeEG) contains a glycosyl hydrolase family 9 (GHF9) catalytic domain with all catalytically important residues conserved, and shows high sequence identity to GHF9 EGs reported from other arthropods. The endogenous origin of PeEG was confirmed by PCR amplification of a ~1.5kb DNA fragment, containing a phase 1 intron flanked by two exon sequences identical to the cDNA, from genomic DNA isolated from the crab's muscle tissue. PeEG encoding cDNA is the first endogenous EG sequence reported from the brachyuran crabs. Using degenerate primers, we also isolated 204bp cDNA fragments with sequences affiliated to EG from the hepatopancreas of eight other mangrove crabs of the Sesarmidae (Neosarmatium trispinosum and Sesarmoides borneensis), Macrophthalmidae (Ilyograpsus daviei, Australoplax tridentata, and Macrophthalmus setosus), Varunidae (Pseudohelice subquadrata), Heloeciidae (Heloecius cordiformis), and Ocypodidae (Uca perplexa) families, suggesting that endogenous cellulase production may be a common characteristic among the detritivorous mangrove crabs. Copyright © 2014 Elsevier Inc. All rights reserved.

Movement patterns and trajectories of ovigerous blue crabs Callinectes sapidus during the spawning migration

Science.gov (United States)

Carr, Sarah D.; Tankersley, Richard A.; Hench, James L.; Forward, Richard B.; Luettich, Richard A.

2004-08-01

Female blue crabs ( Callinectes sapidus Rathbun) migrate from low salinity estuarine regions to high salinity regions near the ocean to release larvae. During this migration, ovigerous females use ebb-tide transport, a vertical migratory behavior in which they ascend into the water column during ebb tides, to move seaward to larval release areas. In order to determine the relationship of ebb-tide vertical migrations to local currents and the influence of these vertical migrations on the horizontal transport of blue crabs in the estuary, ovigerous females with mature embryos (˜1-3 days from hatching) were tracked near Beaufort Inlet, North Carolina (USA), in July and August 2001 and 2002. Crabs were tagged and tracked using ultrasonic telemetry, and currents near the crabs were measured simultaneously with a shipboard acoustic Doppler current profiler. During the two seasons, eight crabs were successfully tracked for periods ranging from 3.9-37.0 h and for distances ranging from 1.9-10.6 km. All crabs migrated seaward during the tracking periods. Crabs moved episodically during all tidal phases with periods of movement on the order of minutes to an hour. They moved with local currents in terms of both speed and direction during ebb tides, consistent with ebb-tide transport, and moved down-estuary (seaward) in opposition to local currents during flood tides. The percentage of time that crabs were active was higher during night ebb tides than during day ebb tides or flood tides and increased with increasing ebb-tide current speed. Mean migratory speeds were 0.11, 0.04, 0.08 and 0.02 m s -1 during night ebb, night flood, day ebb and day flood tides, respectively, and net migratory speeds were on the order of 5 km day -1. Due to the episodic nature of the crabs' movements, the total distances that crabs traveled during ebb tides ranged from 10-40% of the distances that passive particles could have traveled under the same conditions.

Polarization and emission geometry of the Crab pulsar

International Nuclear Information System (INIS)

Kaiyou Chen; Cheng Ho

1993-01-01

Optical emission of the Crab pulsar can best be understood as synchrotron radiation of relativistic particles from the outer magnetosphere of the neutron star. The outer gap model was developed specifically to address energy balance and double-pulsed emission (from optical to high-energy gamma-ray) of young pulsars like the Crab. In this paper, we present the polarization properties of the optical pulses calculated from the outer gap model. We found that the theoretical light curves exhibit the same qualitative behavior as observations

INTEGRATED DRILLING SYSTEM USING MUD ACTUATED DOWN HOLE HAMMER AS PRIMARY ENGINE

Energy Technology Data Exchange (ETDEWEB)

John V. Fernandez; David S. Pixton

2005-12-01

A history and project summary of the development of an integrated drilling system using a mud-actuated down-hole hammer as its primary engine are given. The summary includes laboratory test results, including atmospheric tests of component parts and simulated borehole tests of the hammer system. Several remaining technical hurdles are enumerated. A brief explanation of commercialization potential is included. The primary conclusion for this work is that a mud actuated hammer can yield substantial improvements to drilling rate in overbalanced, hard rock formations. A secondary conclusion is that the down-hole mud actuated hammer can serve to provide other useful down-hole functions including generation of high pressure mud jets, generation of seismic and sonic signals, and generation of diagnostic information based on hammer velocity profiles.

Titanium leaching from red mud by diluted sulfuric acid at atmospheric pressure

International Nuclear Information System (INIS)

Agatzini-Leonardou, S.; Oustadakis, P.; Tsakiridis, P.E.; Markopoulos, Ch.

2008-01-01

Laboratory-scale research has focused on the recovery of titanium from red mud, which is obtained from bauxite during the Bayer process for alumina production. The leaching process is based on the extraction of this element with diluted sulfuric acid from red mud under atmospheric conditions and without using any preliminary treatment. Statistical design and analysis of experiments were used, in order to determine the main effects and interactions of the leaching process factors, which were: acid normality, temperature and solid to liquid ratio. The titanium recovery efficiency on the basis of red mud weight reached 64.5%. The characterization of the initial red mud, as well as this of the leached residues was carried out by X-ray diffraction, TG-DTA and scanning electron microscopy

Beam losses due to abrupt crab cavity failures in the LHC

International Nuclear Information System (INIS)

Baer, T.; Barranco, J.; Calaga, R.; Tomas, R.; Wenninger, B.; Yee, B.; Zimmermann, F.

2011-01-01

A major concern for the implementation of crab crossing in a future High-Luminosity LHC (HL-LHC) is machine protection in an event of a fast crab-cavity failure. Certain types of abrupt crab-cavity amplitude and phase changes are simulated to characterize the effect of failures on the beam and the resulting particle-loss signatures. The time-dependent beam loss distributions around the ring and particle trajectories obtained from the simulations allow for a first assessment of the resulting beam impact on LHC collimators and on sensitive components around the ring. Results for the nominal LHC lattice is presented.

Recovery of rare earths from red mud

International Nuclear Information System (INIS)

Bautista, R.G.

1992-01-01

The prospect for the recovery of rare earths from red mud, the bauxite tailings from the production of alumina is examined. The Jamaican red mud by far has the higher trace concentrations of lanthanum, cerium, neodymium, and yttrium. Scandium is also present. The dissolution of the rare earth is a major extraction problem because of the large volume of other materials. The recovery processes that have been proposed include the production of co-products such as iron, alumina, and titanium concentrates, with the rare earths going with the titanium. In this paper a critical examination of the possible processes are presented with the recommended research projects to be carried out

Method of preparing light-weight plugging mud

Energy Technology Data Exchange (ETDEWEB)

Gorskiy, V F; Melnichuk, A N; Vernikovskiy, A N

1982-01-01

A method is proposed for preparing a light-weight plugging mud which includes mixing Portland cement on an aqueous suspension of palygorskite. It is distinguished by the fact that in order to improve the quality of the mud and strength of the cement stone with simultaneous decrease in the gas permeability, before mixing the Portland cement, the aqueous suspension of palygorskite is dispersed to stabilization of viscosity, and after mixing the Portland cement, the obtained cement-clay mixture is exposed to additional dispersion under pressure. The ratio of the ingredients is the following (% by mass): Portland cement 32.0-61.0; palygorskite 1.2-2.9; water--the rest.

Crabbing system for an electron-ion collider

Energy Technology Data Exchange (ETDEWEB)

Castilla, Alejandro [Old Dominion Univ., Norfolk, VA (United States)

2017-05-01

As high energy and nuclear physicists continue to push further the boundaries of knowledge using colliders, there is an imperative need, not only to increase the colliding beams' energies, but also to improve the accuracy of the experiments, and to collect a large quantity of events with good statistical sensitivity. To achieve the latter, it is necessary to collect more data by increasing the rate at which these processes are being produced and detected in the machine. This rate of events depends directly on the machine's luminosity. The luminosity itself is proportional to the frequency at which the beams are being delivered, the number of particles in each beam, and inversely proportional to the cross-sectional size of the colliding beams. There are several approaches that can be considered to increase the events statistics in a collider other than increasing the luminosity, such as running the experiments for a longer time. However, this also elevates the operation expenses, while increasing the frequency at which the beams are delivered implies strong physical changes along the accelerator and the detectors. Therefore, it is preferred to increase the beam intensities and reduce the beams cross-sectional areas to achieve these higher luminosities. In the case where the goal is to push the limits, sometimes even beyond the machines design parameters, one must develop a detailed High Luminosity Scheme. Any high luminosity scheme on a modern collider considers|in one of their versions|the use of crab cavities to correct the geometrical reduction of the luminosity due to the beams crossing angle. In this dissertation, we present the design and testing of a proof-of-principle compact superconducting crab cavity, at 750 MHz, for the future electron-ion collider, currently under design at Jefferson Lab. In addition to the design and validation of the cavity prototype, we present the analysis of the first order beam dynamics and the integration of the

Additive to clay drilling muds

Energy Technology Data Exchange (ETDEWEB)

Voytenko, V.S.; Nekrasova, V.B.; Nikitinskiy, E.L.; Ponomarev, V.N.

1984-01-01

The purpose of the invention is to improve the lubricating and strengthening properties of clay drilling muds. This goal is achieved because the lubricating and strengthening additive used is waste from the pulp and paper industry at the stage of reprocessing crude sulfate soap into phytosterol.

Evidence of marine debris usage by the ghost crab Ocypode quadrata (Fabricius, 1787).

Science.gov (United States)

Costa, Leonardo Lopes; Rangel, Danilo Freitas; Zalmon, Ilana Rosental

2018-03-01

Sandy beaches are sites of marine debris stranding, but the interaction of beach biota with waste is poorly studied. The objective of this study was to investigate whether the ghost crab Ocypode quadrata selects marine debris by types using a non-destructive method on sandy beaches of Southeastern Brazil. We found marine debris in 7% of 1696 surveyed burrows, and the ghost crabs selectivity was mainly by soft plastic (30%), straw (11%), rope (6%) and foam (4%). Burrows with marine debris showed higher occupation rate (~68%) compared to burrows without debris (~28%), indicating that these materials may increase the capacity of ghost crabs to memorize their burrows placement (homing). The percentage of marine debris was not always related to their amount in the drift line, but ghost crabs used more debris near urbanized areas. Future studies should test whether ghost crabs are using marine debris for feeding, homing or other mechanisms. Copyright © 2018 Elsevier Ltd. All rights reserved.

Time-dependent source model of the Lusi mud volcano

Science.gov (United States)

Shirzaei, M.; Rudolph, M. L.; Manga, M.

2014-12-01

The Lusi mud eruption, near Sidoarjo, East Java, Indonesia, began erupting in May 2006 and continues to erupt today. Previous analyses of surface deformation data suggested an exponential decay of the pressure in the mud source, but did not constrain the geometry and evolution of the source(s) from which the erupting mud and fluids ascend. To understand the spatiotemporal evolution of the mud and fluid sources, we apply a time-dependent inversion scheme to a densely populated InSAR time series of the surface deformation at Lusi. The SAR data set includes 50 images acquired on 3 overlapping tracks of the ALOS L-band satellite between May 2006 and April 2011. Following multitemporal analysis of this data set, the obtained surface deformation time series is inverted in a time-dependent framework to solve for the volume changes of distributed point sources in the subsurface. The volume change distribution resulting from this modeling scheme shows two zones of high volume change underneath Lusi at 0.5-1.5 km and 4-5.5km depth as well as another shallow zone, 7 km to the west of Lusi and underneath the Wunut gas field. The cumulative volume change within the shallow source beneath Lusi is ~2-4 times larger than that of the deep source, whilst the ratio of the Lusi shallow source volume change to that of Wunut gas field is ~1. This observation and model suggest that the Lusi shallow source played a key role in eruption process and mud supply, but that additional fluids do ascend from depths >4 km on eruptive timescales.

Radiological aspects of the usability of red mud as building material additive

International Nuclear Information System (INIS)

Somlai, Janos; Jobbagy, Viktor; Kovacs, Jozsef; Tarjan, Sandor; Kovacs, Tibor

2008-01-01

Several researchers have examined and achieved favourable results in connection with the building industry's use of red mud extracted in large quantities from the processing of bauxite. These days more and more precedence is being given to limiting the radiological dose to the population. In this study carried out in Hungary, the use of red mud, bauxite, and clay additives recommended for the production of special cements, were examined from a radiological aspect. 226 Ra and 232 Th activity concentrations measured in Hungarian bauxite, red mud and clay samples were significantly similar with the levels for such raw materials mentioned in international literature. Taking radiation protection aspects into consideration, none of these products can be directly used for building construction. Taking Hungarian and international values into consideration, a small amount of red mud, not exceeding 15% could be used for brick production, for example as a colouring material. However, beyond this amount the standards for building materials would not be met. For the production of cements an even stricter limit needs to be determined when both bauxite and red mud are used

Source Signature of Sr Isotopes in Fluids Emitting From Mud volcanoes in Taiwan

Science.gov (United States)

Chung, C.; You, C.; Chao, H.

2003-12-01

Located at the boundary between the Philippine Sea Plate and the Asia Continental Plate, abundance of mud volcanoes were erupted on land in Taiwan. According to their occurrences and associated tectonic settings, these mud volcanoes were classified into four groupies. The group (I) mud volcanoes are located in the western coastal plane, whereas group (II) and (III) are situated near the Kutinkung anticline axis and the Chishan fault respectively. The group (IV) mud volcanoes are discovered at the Coastal Range. Although there are numerous studies focused on morphology, possible fluid migration paths and sources are poorly understood. We have collected and analyzed major ions and Sr isotopic ratios in fluids separated from various mud volcanoes in Taiwan. Chemical contents of these fluids were measured by IC and the emitted gasses were analyzed by GC. The Sr concentrations in these fluids were determined using AA and the isotopic compositions were analyzed by TIMS. The dominated ions in fluids are Na and Cl which account for 98% of dissolved materials. All fluids show similar Na/Cl ratios(0.7-0.8), slightly higher than seawater but each group has unique Sr isotopic signature. Waters expelled from group I mud volcanoes featured with low salinity and high Sr isotopic ratios ranged from 0.71150 to 0.71175. Groups II and III were outcroped in the Kutinkung formation but show distinctive chemical compositions. Group II fluids have four times Cl concentrations(358-522mM) compared with those of group III(85-162mM). The latter fluids appear to be more radiogenic(0.71012- 0.71075) indicating possible influence due to water-rock interactions. Low 87Sr/86Sr(0.70692-0.70939) is typical characteristic of mud volcano fluids in group IV where large Mg and K depletion were discovered, suggesting effects due to sediment diagenetic processes. The chemical compositions of mud volcano associated gasses show similar distribution pattern. The major gas constituents in mud volcano zones

Viral infections stimulate the metabolism and shape prokaryotic assemblages in submarine mud volcanoes.

Science.gov (United States)

Corinaldesi, Cinzia; Dell'Anno, Antonio; Danovaro, Roberto

2012-06-01

Mud volcanoes are geological structures in the oceans that have key roles in the functioning of the global ecosystem. Information on the dynamics of benthic viruses and their interactions with prokaryotes in mud volcano ecosystems is still completely lacking. We investigated the impact of viral infection on the mortality and assemblage structure of benthic prokaryotes of five mud volcanoes in the Mediterranean Sea. Mud volcano sediments promote high rates of viral production (1.65-7.89 × 10(9) viruses g(-1) d(-1)), viral-induced prokaryotic mortality (VIPM) (33% cells killed per day) and heterotrophic prokaryotic production (3.0-8.3 μgC g(-1) d(-1)) when compared with sediments outside the mud volcano area. The viral shunt (that is, the microbial biomass converted into dissolved organic matter as a result of viral infection, and thus diverted away from higher trophic levels) provides 49 mgC m(-2) d(-1), thus fuelling the metabolism of uninfected prokaryotes and contributing to the total C budget. Bacteria are the dominant components of prokaryotic assemblages in surface sediments of mud volcanoes, whereas archaea dominate the subsurface sediment layers. Multivariate multiple regression analyses show that prokaryotic assemblage composition is not only dependant on the geochemical features and processes of mud volcano ecosystems but also on synergistic interactions between bottom-up (that is, trophic resources) and top-down (that is, VIPM) controlling factors. Overall, these findings highlight the significant role of the viral shunt in sustaining the metabolism of prokaryotes and shaping their assemblage structure in mud volcano sediments, and they provide new clues for our understanding of the functioning of cold-seep ecosystems.

Mud peeling and horizontal crack formation in drying clays

KAUST Repository

Style, Robert W.

2011-03-01

Mud peeling is a common phenomenon whereby horizontal cracks propagate parallel to the surface of a drying clay. Differential stresses then cause the layer of clay above the crack to curl up to form a mud peel. By treating the clay as a poroelastic solid, we analyze the peeling phenomenon and show that it is caused by the gradient in tensile stress at the surface of the clay, analogously to the spalling of thermoelastic materials. For a constant water evaporation rate at the clay surface we derive equations for the depth of peeling and the time of peeling as functions of the evaporation rate. Our model predicts a simple relationship between the radius of curvature of a mud peel and the depth of peeling. The model predictions are in agreement with the available experimental data. Copyright 2011 by the American Geophysical Union.

Comparative toxicity of offshore and oil-added drilling muds to larvae of the grass shrimp Palaemonetes intermedius

Energy Technology Data Exchange (ETDEWEB)

Conklin, P.J.; Rao, K.R.

1984-11-01

Offshore drilling fluids (muds) varied widely in their toxicity to grass shrimp (Palaemonetes intermedius) larvae. The 96-h LC/sub 50/s for the eleven drilling muds tested ranged from 142 to > 100,000 ppM (..mu..l/L). There was a significant correlation between oil content of the drilling muds and their toxicity. Furthermore, addition of diesel oil (No. 2 fuel oil) or mineral oil to an offshore drilling mud having a low oil content or to an oil-free synthetic drilling mud led to a marked increase in the toxicity of these muds. Thus, much of the toxicity of the offshore drilling muds tested can be attributable to the oil content. 24 references, 2 figures, 3 tables.

Assessing SfM-Photogrammetry potential at micro-scale on a rapidly evolving mud-bank: case study on a mesocosm study within pioneer mangroves in French Guiana (South America)

Science.gov (United States)

Fleury, Jules; Brunier, Guillaume; Michaud, Emma; Anthony, Edward; Dussouillez, Philippe; Morvan, Sylvain

2016-04-01

Mud banks are the loci of rich bio-geo-chemical processes occuring rapidly at infra-tide frequency. Their surface topography is commonly affected by many of these processes, including bioturbation, water drainage or dessication. Quantifying surface morphology and changes on a mud bank at the micro-scale is a challenging task due to a number of issues. First, the water-saturated nature of the soil makes it difficult to measure High Resolution Topography (HRT) with classical methods. Second, setting up an instrumented experiment without disrupting the signal being studied is hardly achieved at micro-scale. Finally, the highly mobile nature of this environment enhancing strong spatio-temporal heterogeneity is hard to capture. Terrestrial Laser Scanning (TLS) and SfM (Surface from Motion)-Photogrammetry are two techniques that enable mapping of micro-scale features, but the first technique is not suitable because of the poor quality of the backscattered laser signal on wet surfaces and the need to set up several measuring stations on a complex, unstable substrate. Thus, we set up an experiment to assess the feasibility and the accuracy of SfM in such a context. We took the opportunity of the installation of a pontoon dedicated to the study of bio-geochemical processes within benthic mesocosms installed on a mud bank inhabited by pioneer mangroves trees to develop an adapted photogrammetry protocol based on a full-frame remotely triggered camera sensor mounted on a pole. The incident light on the surface was also controlled with a light-diffusing device. We obtained sub-millimetric resolution 3D-topography and visible imagery. Surveys were carried out every 2 hours at low tide to detect surface changes due to water content variation as well as bioturbation mainly caused by crabs digging galleries and feeding on sediment surface. Both the qualitative and quantitative results seem very promising and lead us to expect new insights into heterogeneous surface processes on a

Geochemical recovery of the Torna-Marcal river system after the Ajka red mud spill, Hungary.

Science.gov (United States)

Anton, Á D; Klebercz, O; Magyar, Á; Burke, I T; Jarvis, A P; Gruiz, K; Mayes, W M

2014-12-01

The failure of the Ajka red mud depository in October 2010 led to the largest single release of red mud into the surface water environment. This study provides a comparative assessment of stream sediment quality in the Torna-Marcal-Rába catchment between post-disaster surveys (2010) and follow up surveys at an identical suite of 21 locations in 2013. The signature of red mud apparent in initial surveys with high Al, As, Cr, Na, V was only apparent at a small number of sample stations in recent surveys. These constitute 20 km reach of affected sediments in the immediate aftermath of the spill. Concentrations of red mud-derived contaminants are predominately associated with fine fractions of the red mud (mud-derived contaminants and, along with extensive remedial efforts, has substantially limited the within-channel inventory of potentially ecotoxic metals and metalloids.

Present and future distributions of horseshoe crabs under predicted climate changes

DEFF Research Database (Denmark)

Funch, Peter; Obst, Matthias; Quevedo, Francisco

The habitats of South East Asian horseshoe crabs span across the shallow waters of many countries and biogeographic regions in the Indo-Pacific. Such ubiquitous presence makes it difficult to obtain an up-to-date and overall picture of the current distribution, density and wealth of horseshoe crab...

Responses of the crab Heterozius rotundifrons to heterospecific chemical alarm cues: phylogeny vs. ecological overlap.

Science.gov (United States)

Hazlett, Brian A; McLay, Colin

2005-03-01

The big-handed brachyuran crab Heterozius rotundifrons extends the time spent in its anti-predator posture, limb extended posture, if exposed to chemical cues from crushed conspecifics. In this study, we tested whether crabs also respond to chemical cues from crushed heterospecific crabs, and if so, whether phylogenetic relations or ecological overlap is more important in influencing the duration of the anti-predator posture. Chemical cues from two other brachyuran crabs (Cyclograpsus lavauxi and Hemigrapsus sexdentatus), which do not overlap directly in ecological distribution with H. rotundifrons, elicited a duration of the anti-predator posture that was indistinguishable from that produced by conspecific chemical cues. In contrast, chemical cues from two anomuran crabs (Petrolisthes elongatus and Pagurus novizealandiae) that overlap in ecological distribution with H. rotundifrons, elicited durations of the antipredator posture that were significantly shorter than those of either conspecifics or more closely related crab species. Thus, phylogenetic relationship seems to be more important than ecological overlap in influencing anti-predator behavior in H. rotundifrons.

Shell use and partitioning of two sympatric species of hermit crabs on a tropical mudflat

Science.gov (United States)

Teoh, Hong Wooi; Chong, Ving Ching

2014-02-01

Shell use and partitioning of two sympatric hermit crab species (Diogenes moosai and Diogenes lopochir), as determined by shell shape, size and availability, were examined from August 2009 to March 2011 in a tropical mudflat (Malaysia). Shells of 14 gastropod species were used but > 85% comprised shells of Cerithidea cingulata, Nassarius cf. olivaceus, Nassarius jacksonianus, and Thais malayensis. Shell partitioning between hermit crab species, sexes, and developmental stages was evident from occupied shells of different species, shapes, and sizes. Extreme bias in shell use pattern by male and female of both species of hermit crabs suggests that shell shape, which depends on shell species, is the major determinant of shell use. The hermit crab must however fit well into the shell so that compatibility between crab size and shell size becomes crucial. Although shell availability possibly influenced shell use and hermit crab distribution, this is not critical in a tropical setting of high gastropod diversity and abundance.

Interference competition as a key determinant for spatial distribution of mangrove crabs

KAUST Repository

Cannicci, Stefano

2018-02-15

The spatial distribution of mangrove crabs has been commonly associated with tree zonation and abiotic factors such as ground temperature and soil granulometry. Conversely, no studies were designed to investigate the role of competition for resources and predation in shaping crab distribution in mangroves, despite these biotic factors are recognised as key determinants for spatial patterns observed in the communities colonising rocky and sandy intertidal habitats.We studied floral and faunal assemblages in two zones of a Sri Lankan mangrove, a man-made upper intertidal level and a natural eulittoral, mid-shore one. Leaf choice experiments were designed to study both feeding rate and intra and inter-specific interactions for food of sesarmid crabs in the two habitats in order to better understand crab spatial distribution.The two intertidal belts differed in terms of floral composition and crab species abundance. The eulittoral zone was strongly dominated by Neosarmatium smithi, while within the elevated littoral fringe four sesarmids (N. smithi, N. asiaticum, N. malabaricum and Muradium tetragonum) were more evenly distributed. At both levels, all sesarmids showed to collect significantly more Bruguiera spp. and Rhizophora apiculata leaves than Excoecaria agallocha ones. There was no temporal segregation in feeding activity among the four species, resulting in a high interference competition for leaves. Regardless of the habitat, N. smithi was always successful in winning inter-specific fights.Our results showed that the elevated littoral fringe was more crowded with crabs, but was less favourable in terms of food availability and environmental conditions. The dominance of N. smithi in gathering mangrove leaves suggests that this species may segregate the other sesarmids into less favourable habitats. The present data strongly suggest for the first time that interference competition for food can contribute to shape mangrove crab spatial distribution.

Electroless nickel – phosphorus coating on crab shell particles and its characterization

Energy Technology Data Exchange (ETDEWEB)

Arulvel, S., E-mail: gs.arulvel.research@gmail.com; Elayaperumal, A.; Jagatheeshwaran, M.S.

2017-04-15

Being hydrophilic material, crab shell particles have only a limited number of applications. It is, therefore, necessary to modify the surface of the crab shell particles. To make them useful ever for the applications, the main theme we proposed in this article is to utilize crab shell particles (CSP) with the core coated with nickel phosphorus (NiP) as a shell using the electroless coating process. For dealing with serious environmental problems, utilization of waste bio-shells is always an important factor to be considered. Chelating ability of crab shell particles eliminates the surface activation in this work proceeding to the coating process. The functional group, phase structure, microstructure, chemical composition and thermal analysis of CSP and NiP/CSP were characterized using Fourier transform infra-red spectroscopy (FTIR), x-ray diffraction analyzer (XRD), scanning electron microscope (SEM), energy-dispersive x-ray spectroscopy (EDS), and thermogravimetric analysis (TGA). The combination of an amorphous and crystalline structure was exhibited by CSP and NiP/CSP. NiP/CSP has shown a better thermal stability when compared to uncoated CSP. Stability test, adsorption test, and conductivity test were conducted for the study of adsorption behavior and conductivity of the particles. CSP presented a hydrophilic property in contrast to hydrophobic NiP/CSP. NiP/CSP presented a conductivity of about 44% greater compared to the CSP without any fluctuations. - Highlights: • Utilization of crab shell waste is focused on. • NiP coating on crab shell particle is fabricated using electroless process. • Thermal analysis, stability test, adsorption test and conductivity test were done. • Organic matrix of crab shell particle favors the coating process. • Results demonstrate the characterization of CSP core – NiP shell structure.

Interference competition as a key determinant for spatial distribution of mangrove crabs

KAUST Repository

Cannicci, Stefano; Fusi, Marco; Cimó , Filippo; Dahdouh-Guebas, Farid; Fratini, Sara

2018-01-01

The spatial distribution of mangrove crabs has been commonly associated with tree zonation and abiotic factors such as ground temperature and soil granulometry. Conversely, no studies were designed to investigate the role of competition for resources and predation in shaping crab distribution in mangroves, despite these biotic factors are recognised as key determinants for spatial patterns observed in the communities colonising rocky and sandy intertidal habitats.We studied floral and faunal assemblages in two zones of a Sri Lankan mangrove, a man-made upper intertidal level and a natural eulittoral, mid-shore one. Leaf choice experiments were designed to study both feeding rate and intra and inter-specific interactions for food of sesarmid crabs in the two habitats in order to better understand crab spatial distribution.The two intertidal belts differed in terms of floral composition and crab species abundance. The eulittoral zone was strongly dominated by Neosarmatium smithi, while within the elevated littoral fringe four sesarmids (N. smithi, N. asiaticum, N. malabaricum and Muradium tetragonum) were more evenly distributed. At both levels, all sesarmids showed to collect significantly more Bruguiera spp. and Rhizophora apiculata leaves than Excoecaria agallocha ones. There was no temporal segregation in feeding activity among the four species, resulting in a high interference competition for leaves. Regardless of the habitat, N. smithi was always successful in winning inter-specific fights.Our results showed that the elevated littoral fringe was more crowded with crabs, but was less favourable in terms of food availability and environmental conditions. The dominance of N. smithi in gathering mangrove leaves suggests that this species may segregate the other sesarmids into less favourable habitats. The present data strongly suggest for the first time that interference competition for food can contribute to shape mangrove crab spatial distribution.

Comparing the efficacy of mature mud pack and hot pack treatments for knee osteoarthritis.

Science.gov (United States)

Sarsan, Ayşe; Akkaya, Nuray; Ozgen, Merih; Yildiz, Necmettin; Atalay, Nilgun Simsir; Ardic, Fusun

2012-01-01

The objective of this study is to compare the efficacy of mature mud pack and hot pack therapies on patients with knee osteoarthritis. This study was designed as a prospective, randomized-controlled, and single-blinded clinical trial. Twenty-seven patients with clinical and radiologic evidence of knee osteoarthritis were randomly assigned into two groups and were treated with mature mud packs (n 15) or hot packs (n=12). Patients were evaluated for pain [based on the visual analog scale (VAS)], function (WOMAC, 6 min walking distance), quality of life [Short Form-36 (SF-36)], and serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and insulin-like growth factor-1 (IGF-1) at baseline, post-treatment, and 3 and 6~months after treatment. The mud pack group shows a significant improvement in VAS, pain, stifness, and physical function domains of WOMAC. The difference between groups of pain and physical activity domains is significant at post-treatment in favor of mud pack. For a 6 min walking distance, mud pack shows significant improvement, and the difference is significant between groups in favor of mud pack at post-treatment and 3 and 6 months after treatment. Mud pack shows significant improvement in the pain subscale of SF-36 at the third month continuing until the sixth month after the treatment. Significant improvements are found for the social function, vitality/energy, physical role disability, and general health subscales of SF-36 in favor of the mud pack compared with the hot pack group at post-treatment. A significant increase is detected for IGF-1 in the mud pack group 3 months after treatment compared with the baseline, and the difference is significant between groups 3 months after the treatment. Mud pack is a favorable option compared with hotpack for pain relief and for the improvement of functional conditions in treating patients with knee osteoarthritis.

Red mud application in construction industry: review of benefits and possibilities

Science.gov (United States)

Lima, M. S. S.; Thives, L. P.; Haritonovs, V.; Bajars, K.

2017-10-01

Red mud is a waste originated in the processing of bauxite into aluminium, which properties of high alkalinity make it cumulatively stored, occupying increasing deforested areas. Annually, it is estimated that approximately 117 million tons of red mud are generated in the world, with no prospect of use, what represents an imminent risk of pollution prone to contamination. Nevertheless, environmental liabilities caused by red mud affect not only the environment, but also the companies responsible for the waste, which will be subject to highest fee payments. Although there are studies that prove the feasibility of using this solid waste in the constitution of ceramic materials, there are no large-scale applications. This study seeks to evaluate the possibilities of red mud application in construction industry, focusing into two main areas: cement production/ceramic material and road construction. Backgrounds from other researchers were taken into consideration and analysed according environmental, economic and technical feasibilities.

A novel approach in red mud neutralization using cow dung.

Science.gov (United States)

Patel, Sucharita; Pal, Bhatu Kumar; Patel, Raj Kishore

2018-05-01

In this study, cow dung was identified as a neutralizing agent for red mud (RM). Present research estimated a significant reduction in pH value of red mud (10 g) from 10.28 to 8.15 and reduction in alkalinity of ~148 mg/L from ~488 mg/L by adding 80 g of cow dung in 40 days of anaerobic condition. XRD results exhibit a high intensity of quartz and found new compound, the calcium carbide. The acid neutralizing capacity (ANC) of NRM reduces to ~0.87 from ~1.506 mol H + /kg. Based on the resultant research, present study proposes cow dung as an efficient neutralizing agent for reducing the pH and alkalinity in the red mud.

Hypolobocera guayaquilensis (Decapoda: Pseudothelphusidae): A New Crab Intermediate Host of Paragonimus mexicanus in Manabí Province, Ecuador

Science.gov (United States)

Calvopina, Manuel; Romero-Alvarez, Daniel; Rendon, Melina; Takagi, Hidekazu; Sugiyama, Hiromu

2018-01-01

To determine that Paragonimus sp. is actively transmitted in a tropical area of the Pacific region of Ecuador where human cases of pulmonary paragonimiasis have recently been documented, a total of 75 freshwater crabs were collected from 2 different streams in the Pedernales area of Manabí Province, Ecuador. All collected crabs were identified as Hypolobocera guayaquilensis based on morphological characteristics of the male gonopods. The hepatopancreas of each crab was examined by compressing it between 2 glass plates followed by observation under a stereomicroscope. Excysted Paragonimus metacercariae were detected in 39 (52.0%) crabs and their densities varied from 1 to 32 per infected crab. There was a positive relationship between crab size and metacercarial density. Sequences of the second internal transcribed spacer region of the ribosomal RNA gene of the Paragonimus metacercariae obtained in this study were identical to those of Paragonimus mexicanus deposited in the DDBJ/EMBL/GenBank database. Thus, the present study is the first to confirm that the crab species H. guayaquilensis is the second intermediate host of P. mexicanus in Manabí Province, Ecuador. Because this crab might be the possible source of human infections in this area, residents should pay attention to improper crab-eating habits related with a neglected parasitic disease, i.e., paragonimiasis. PMID:29742874

The condition and ways to develop operations to establish standards for drilling muds in the ''Grozneft''' Union

Energy Technology Data Exchange (ETDEWEB)

Baranov, V S; Volkova, A P

1979-01-01

Four intervals are strictly defined in the geological section of the sites of ''Grozneft''', which require the use of different types of drilling muds (R). The upper part of the section to the Karagano-Chokraksk sediments inclusively should be drilled with wash through by limestone clay mud, whose use should begin immediately after the lowering of the conducter. The upper Maykop sediments should be drilled with the use of a weighted limestone mud, strictly observing the concentration of the lime and the caustic soda in the mud. In the deposits of the lower Maykop, where the temperature reaches 120/sup 0/C, a gypsum and clay mud should be used, using oxyl for regulating its viscosity. In the deposits of the Upper Cretaceous, for which absorption is characteristic, it is expedient to wash through with water or clay mud, processed by UShchR and bichromate. The deposits of the lower Cretaceous should be drilled with wash through by a gypsum mud, processed by lignosulfonates, where it is recommended to use KSSB-4. The capability is assumed of using chlorocalcium clay mud in drilling the Maykop clays. A condition for the effective use of any types of drilling muds is the improved system for removing drilled out rock from the mud.

Effect of self-glazing on reducing the radioactivity levels of red mud based ceramic materials

Energy Technology Data Exchange (ETDEWEB)

Qin, Shuo [College of Material Science and Engineering, Guilin University of Technology, Guilin, Guangxi 541004 (China); Wu, Bolin, E-mail: wubolin3211@gmail.com [College of Material Science and Engineering, Guilin University of Technology, Guilin, Guangxi 541004 (China)

2011-12-30

Graphical abstract: Self-glazing red mud based ceramic materials (RMCM) were produced by normal pressure sintering process using the main raw materials of red mud. The properties of the RMCM samples were investigated by the measurements of mechanical properties, radiation measurement, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the self-glazing RMCM have good mechanical properties (water absorption and apparent porosity approached zero; bulk density, 2.94 g/cm{sup 3}; compressive strength, 78.12 MPa). The radiation level has clear change regularity that the radioactivity levels of red mud (6360 Bq) are obvious declined, and can be reduced to that of the natural radioactive background of Guilin Karst landform, China (3600 Bq). It will not only consume large quantities of red mud, but also decrease the production cost of self-glazing RMCM. And the statement of this paper will offer effective ways to reduce the radioactivity level of red mud. Highlights: Black-Right-Pointing-Pointer The self-glazing phenomenon in red mud system was first discovered in our research. Black-Right-Pointing-Pointer Radiation levels of red mud can be reduced efficiently by self-glazing layer. Black-Right-Pointing-Pointer Red mud based ceramic materials will not cause harm to environment and humans. Black-Right-Pointing-Pointer This research possesses important economic significances to aluminum companies. - Abstract: Self-glazing red mud based ceramic materials (RMCM) were produced by normal pressure sintering process using the main raw materials of red mud. The properties of the RMCM samples were investigated by the measurements of mechanical properties, radiation measurement, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the self-glazing RMCM have good mechanical properties (water absorption and apparent porosity approached zero; bulk density, 2.94 g/cm{sup 3}; compressive strength, 78.12 MPa). The radiation

Sensory Characteristics of Mud Clam (Polymesoda Erosa) Hydrolysate

International Nuclear Information System (INIS)

Normah Ismail; Noorasma Mustakim

2016-01-01

Mud clam (Polymesoda erosa) was hydrolysed using two different microbial enzymes; alcalase and flavourzyme. The volatile compounds, amino acids and molecular weight associated with umami and bitter taste in mud clam hydrolysate were determined by head space solid phase micro-extraction gas chromatography (HS-SPME-GCMS), High performance liquid chromatography (HPLC) and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The characteristics of hydrolysates produced using alcalase and flavourzyme were compared. In total, eighteen, seven and six volatile compounds were identified in the flesh, alcalase hydrolysate and flavourzyme hydrolysate, respectively. 2-piperidinone volatile compound content which is associated with bitterness was 6.79 % in alcalase hydrolysate and 3.78 % in flavourzyme hydrolysate. SDS-PAGE results showed that alcalase hydrolysate contains smaller peptide (<52 kDa) compared to flavourzyme hydrolysate (<126 kDa). In addition, sensory analysis using quantitative descriptive analysis (QDA) showed that flavourzyme hydroysate was the least bitter but elicited more umami taste compared to alcalase hydrolysate. Further treatments are still needed to enhance umami taste and to remove bitter taste in mud clam hydrolysate. (author)

Scientific studies on decorated mud mortar of Ajanta

Directory of Open Access Journals (Sweden)

M. Singh

2014-01-01

Full Text Available This study is an attempt to reveal the decorated earthen plaster of Ajanta. The mud plaster of Ajanta caves has been analyzed with the help of physical and analytical tools. The results indicate that high silt (>70% low clay soil may have been mixed purposefully with lime (calcite for the reason to enhance the cementing characteristics. The presence of calcium oxalate was detected from FTIR spectra may have been the resultant product of proteic materials presented in mud plaster. Ferrugineous silicate along with rarer gluconite–celendonite and white zeolites were also perceived from SEM and FTIR spectral analysis. The existence of quartz and sepiolite in mud mortar was also detected from XRD and SEM studies. The vegetal matter might have been added to tailor the construction behavior. The analytical results authenticate the similarity of earthen plaster of Ajanta and alluvion deposits of Waghura River just in front of caves, probably used as raw material in improvement of new material that suits for restoration for optimize performance and compatibility with the existing materials.

The Crab pulsar at VHE

Directory of Open Access Journals (Sweden)

Zanin Roberta

2017-01-01

Full Text Available The last six years have witnessed major revisions of our knowledge about the Crab Pulsar. The consensus scenario for the origin of the high-energy pulsed emission has been challenged with the discovery of a very-high-energy power law tail extending up to ~400 GeV, above the expected spectral cut off at a few GeV. Now, new measurements obtained by the MAGIC collaboration extend the energy spectrum of the Crab Pulsar even further, on the TeV regime. Above ~400 GeV the pulsed emission comes mainly from the interpulse, which becomes more prominent with energy due to a harder spectral index. These findings require γ -ray production via inverse Compton scattering close to or beyond the light cylinder radius by an underlying particle population with Lorentz factors greater than 5 × 106. We will present those new results and discuss the implications in our current knowledge concerning pulsar environments.

Evaluation of some vanillin-modified polyoxyethylene surfactants as additives for water based mud

Directory of Open Access Journals (Sweden)

M.M.A. El-Sukkary

2014-03-01

Full Text Available Water-based drilling fluids are increasingly being used for oil and gas exploration and are generally considered to be more environmentally acceptable than oil-based or synthetic-based fluids. In this study, new types of vanillin-modified polyoxyethylene surfactants were evaluated as additives in water-based mud. Their rheological properties in water-based mud were investigated which included the apparent viscosity, the plastic viscosity, the yield point, the gel strength, the thixotropy as well as the filtration properties. Also, the effect of high temperature on the rheology of the formulated water based mud was studied. The tested ethoxylated non-ionic surfactants showed good results when utilized in the formulation of water-based mud.

Engineered covers for mud pit closures Central Nevada Test Area, Nevada

International Nuclear Information System (INIS)

Madsen, D.D.

2000-01-01

Two abandoned drilling mud pits impacted with petroleum hydrocarbons were determined to require closure action at the Central Nevada Test Area. The UC-4 Mud Pit C is approximately 0.12 hectares (0.3 acres) and 1.2 meters (4 feet) in depth. The UC-1 Central Mud Pit (CMP) is approximately 1.54 hectares (3.8 acres) and 2.4 meters (8 feet) in depth. Both mud pits contain bentonite drilling muds with a thin dry crust, low shear strength, low permeability, and high moisture content. The following closure methodologies were evaluated: stabilization by mixing/injection with soil, fly ash, and lime; excavation and disposal; on-site drying; thermal destruction; wick drains; administrative closure (postings and land-use restrictions); and engineered covers. Based upon regulatory closure criteria, implementation, and cost considerations, the selected remedial alternative was the construction of an engineered cover. A multilayered cover with a geo-grid and geo-synthetic clay liner (GCL) was designed and constructed over the UC-4 Mud Pit C to evaluate the constructability and applicability of the design for the CMP cover. The geo-grid provided structural strength for equipment and material loads during cover construction, and the GCL was used as a moisture infiltration barrier. The design was determined to be constructable and applicable. To reduce project costs for the CMP cover, a vegetative cover was designed with drainage toward the center of the cover rather than the perimeter. The vegetative cover with the internal drainage design resulted in a fill volume reduction of approximately 63 percent compared to the multilayered cover design with a GCL

Artificial lights improve the catchability of snow crab (Chionoecetes opilio traps

Directory of Open Access Journals (Sweden)

Khanh Q. Nguyen

2017-05-01

Full Text Available This study investigated the behaviour and commercial catchability of snow crab (Chionoecetes opilio in response to different low-powered LED lights under laboratory and field conditions. We created a novel choice-experiment in a laboratory setting in which we investigated the behaviour of snow crab in response to coloured LED lights. The results showed that snow crab movement was dependent on light colour, with animals choosing to move toward blue and white lights, away from purple lights, and no detectable effect for green and red lights. We then conducted two field experiments to investigate the effect of the same LED lights on the catch rates of commercial traps during the 2016 snow crab fishery on the east coast of Newfoundland and Labrador. Results from the first field experiment showed that adding white and purple LED lights into baited traps significantly improved Catch Per Unit Effort (CPUE by 77% and 47% respectively. Results from the second field experiment showed that unbaited traps equipped with only LED lights (no bait, could also catch snow crab in comparable amounts to traditional baited traps, with soak time and depth explaining some of the variation in CPUE. Taken together, these experiments suggest that fishing enterprises can improve their catching performance and profitability by adding LED lights to their traps, or by using LED lights as a bait replacement.

76 FR 25545 - Safety Zone; Blue Crab Festival Fireworks Display, Little River, Little River, SC

Science.gov (United States)

2011-05-05

...-AA00 Safety Zone; Blue Crab Festival Fireworks Display, Little River, Little River, SC AGENCY: Coast... zone on the waters of Little River in Little River, South Carolina during the Blue Crab Festival... this rule because the Coast Guard did not receive notice of the Blue Crab Festival Fireworks Display...

Giant robber crabs monitored from space: GPS-based telemetric studies on Christmas Island (Indian Ocean).

Science.gov (United States)

Krieger, Jakob; Grandy, Ronald; Drew, Michelle M; Erland, Susanne; Stensmyr, Marcus C; Harzsch, Steffen; Hansson, Bill S

2012-01-01

We investigated the navigational capabilities of the world's largest land-living arthropod, the giant robber crab Birgus latro (Anomura, Coenobitidae); this crab reaches 4 kg in weight and can reach an age of up to 60 years. Populations are distributed over small Indo-Pacific islands of the tropics, including Christmas Island (Indian Ocean). Although this species has served as a crustacean model to explore anatomical, physiological, and ecological aspects of terrestrial adaptations, few behavioral analyses of it exist. We used a GPS-based telemetric system to analyze movements of freely roaming robber crabs, the first large-scale study of any arthropod using GPS technology to monitor behavior. Although female robber crabs are known to migrate to the coast for breeding, no such observations have been recorded for male animals. In total, we equipped 55 male robber crabs with GPS tags, successfully recording more than 1,500 crab days of activity, and followed some individual animals for as long as three months. Besides site fidelity with short-distance excursions, our data reveal long-distance movements (several kilometers) between the coast and the inland rainforest. These movements are likely related to mating, saltwater drinking and foraging. The tracking patterns indicate that crabs form route memories. Furthermore, translocation experiments show that robber crabs are capable of homing over large distances. We discuss if the search behavior induced in these experiments suggests path integration as another important navigation strategy.

Colour change and camouflage in juvenile shore crabs Carcinus maenas

Directory of Open Access Journals (Sweden)

Martin eStevens

2014-05-01

Full Text Available Camouflage is perhaps the most widespread anti-predator defense in nature, with many different types thought to exist. Of these, resembling the general color and pattern of the background (background matching is likely to be the most common. Background matching can be achieved by adaptation of individual appearance to different habitats or substrates, behavioral choice, and color change. Although the ability to change coloration for camouflage over a period of hours or days is likely to be widely found among animals, few studies have quantified this against different backgrounds. Here, we test whether juvenile shore crabs (Carcinus maenas are capable of color change for camouflage by placing them on either black or white (experiment 1 or red and green (experiment 2 backgrounds. We find that crabs are capable of significant changes in brightness, becoming lighter on white backgrounds and darker on black backgrounds. Using models of predator (avian vision, we show that these differences are large enough in many individuals to lead to perceptible changes in appearance. Furthermore, comparisons of crabs with the backgrounds show that changes are likely to lead to significant improvements in camouflage and potentially reduced detection probabilities. Crabs underwent some changes on the red and green backgrounds, but visual modeling indicated that these changes were very small and unlikely to be detectable. Our experiment shows that crabs are able to adjust their camouflage by changes in brightness over a period of hours, and that this could influence detection probability by predators.

Neutralization of red mud with pickling waste liquor using Taguchi's design of experimental methodology.

Science.gov (United States)

Rai, Suchita; Wasewar, Kailas L; Lataye, Dilip H; Mishra, Rajshekhar S; Puttewar, Suresh P; Chaddha, Mukesh J; Mahindiran, P; Mukhopadhyay, Jyoti

2012-09-01

'Red mud' or 'bauxite residue', a waste generated from alumina refinery is highly alkaline in nature with a pH of 10.5-12.5. Red mud poses serious environmental problems such as alkali seepage in ground water and alkaline dust generation. One of the options to make red mud less hazardous and environmentally benign is its neutralization with acid or an acidic waste. Hence, in the present study, neutralization of alkaline red mud was carried out using a highly acidic waste (pickling waste liquor). Pickling waste liquor is a mixture of strong acids used for descaling or cleaning the surfaces in steel making industry. The aim of the study was to look into the feasibility of neutralization process of the two wastes using Taguchi's design of experimental methodology. This would make both the wastes less hazardous and safe for disposal. The effect of slurry solids, volume of pickling liquor, stirring time and temperature on the neutralization process were investigated. The analysis of variance (ANOVA) shows that the volume of the pickling liquor is the most significant parameter followed by quantity of red mud with 69.18% and 18.48% contribution each respectively. Under the optimized parameters, pH value of 7 can be achieved by mixing the two wastes. About 25-30% of the total soda from the red mud is being neutralized and alkalinity is getting reduced by 80-85%. Mineralogy and morphology of the neutralized red mud have also been studied. The data presented will be useful in view of environmental concern of red mud disposal.

Gamma rays and neutrinos from the Crab Nebula produced by pulsar accelerated nuclei

OpenAIRE

Bednarek, W.; Protheroe, R. J.

1997-01-01

We investigate the consequences of the acceleration of heavy nuclei (e.g. iron nuclei) by the Crab pulsar. Accelerated nuclei can photodisintegrate in collisions with soft photons produced in the pulsar's outer gap, injecting energetic neutrons which decay either inside or outside the Crab Nebula. The protons from neutron decay inside the nebula are trapped by the Crab Nebula magnetic field, and accumulate inside the nebula producing gamma-rays and neutrinos in collisions with the matter in t...

Characterization of red mud-epoxy intumescent char using surface imaging and micro analysis

Energy Technology Data Exchange (ETDEWEB)

Arogundade, A. I., E-mail: ajiunolorioba@gmail.com; Megat-Yusoff, P. S. M., E-mail: puteris@petronas.com.my; Faiz, A. [Department of Mechanical Engineering, Universiti Tecknologi Petronas (Malaysia); Bhat, A. H. [Department of Fundamental and Applied Science, Universiti Tecknologi Petronas (Malaysia)

2015-07-22

In this study, red mud (RM), an oxide waste was proposed as reinforcing, synergistic filler for the traditional epoxy intumescent coating (IC). 5.5 wt% of acid-modified and unmodified red mud were introduced into the basic intumescent formulation of ammonium polyphosphate (APP), pentaerythritol (PER) and melamine (MEL). In order to predict effect of modification on its suitability, Field emission electron scanning microscopy and Fourier transform infra red were used to obtain detailed characteristics such as the cell size, pore distribution, homogeneity and chemical composition of the red mud-epoxy carbonaceous char. Both acid-modified and unmodified RM-filled ICs produced chars with smaller and more closely packed cells compared to chars from the unfilled coating. Both coating types had hard carbonaceous metal phosphate coverings that could act as heat barriers. The unmodified red mud was found to be antagonistic to the intumescent action with an expansion of only 2 times the initial thickness. The leached, low iron-red mud produced an expansion of 15 times the initial thickness, but possessed a hollow interior. From these findings, it may be deduced that while acid leaching of red mud may improve intumescent expansion, it would be necessary to optimize the percent filler loading to improve residual mass.

Start up study of UASB reactor treating press mud for biohydrogen production

International Nuclear Information System (INIS)

Radjaram, B.; Saravanane, R.

2011-01-01

Anaerobic digestion of press mud mixed with water for biohydrogen production was performed in continuous fed UASB bioreactor for 120 days. Experiment was conducted by maintaining constant HRT of 30 h and the volume of biohydrogen evolved daily was monitored. Various parameters like COD, VFA, Alkalinity, EC, Volatile solids, pH with respect to biohydrogen production were monitored at regular interval of time. SBPR was 10.98 ml g -1 COD reduced d -1 and 12.77 ml g -1 VS reduced d -1 on peak yield of biohydrogen. COD reduction was above 70 ± 7%. Maximum gas yield was on the 78th day to 2240 ml d -1 . The aim of the experiment is to study the startup process of UASB reactor for biohydrogen production by anaerobic fermentation of press mud. The inoculum for the process is cow dung and water digested in anaerobic condition for 30 days with municipal sewage sludge. The study explores the viability of biohydrogen production from press mud which is a renewable form of energy to supplement the global energy crisis. -- Highlights: → Feasibility of biohydrogen production from press mud was explored in this study. The gas yield was maximum on the 78th day to 2240 ml d -1 with H 2 % of 52-59%. Biohydrogen yield was about 890 ml kg -1 press mud added d -1 . Press mud is identified as an excellent potential waste to tap energy.

Ex-vivo evaluation of crab shell chitosan as absorption enhancer in ...

African Journals Online (AJOL)

This study was aimed at evaluating crab shell chitosan as absorption enhancer in ciprofloxacin tablet formulation using the ex-vivo model. Six batches of ciprofloxacin tablets containing varying concentrations of crab shell-derived chitosan ranging from 0 to 5% w/w at 1% w/w intervals were produced. Batch CTS-0 ...

Function of drilling mud during well boring

Energy Technology Data Exchange (ETDEWEB)

Martinko, B

1982-01-01

This paper provides an analysis of primary functions that an emulsion mud must have when shallow wells are drilled: remove drilled waste matter from well, monitor stratal pressure, retain material when circulation is absent, release material to the surface, form an impermeable clay coating on walls of the well, prevent caving of soil, and prevent instrument corrosion. Recommendations are provided to achieve the above listed requirements in mud characteristics: density, filtration, viscosity, gelation and alkalization must be adjusted to the given requirements. It is concluded that fresh water alone cannot satisfy all the necessary requirements and it is recommended to avoid using it where possible, and instead utilize water with additives (emulsions). A number of water and additive compositions are offered. A polymer solution, consisting of water, NaCl or CaCl/sub 2/ to the required density, polymer (vegetative rubber or hydroxethylcellulose) in the amount of 3-6 kg/m/sup 3/ for circulation and 6-9 kg/m/sup 3/ when there's mud loss, can be utilized. Also finely ground CaCO/sub 3/ in the amount of 20-30 kg/m/sup 3/ can be utilized for cementing media. Formulas for a bentonite emulsion and others are included.

Clash of the crabs: Interspecific, inter-cohort competition between the native European green crab, Carcinus maenas and the exotic brush clawed crab Hemigrapsus takanoi on artificial oyster reefs

Science.gov (United States)

van den Brink, Anneke; Hutting, Samara

2017-10-01

Interaction between cohorts was investigated with juveniles of the native crab Carcinus maenas and adults of the exotic crab Hemigrapsus takanoi on artificial, intertidal oyster reefs. The reefs are occupied by C. maenas seasonally as a nursery habitat and consistently by adult H. takanoi. There was a distinct decrease in abundance of C. maenas of the same carapace width as most adult H. takanoi, suggesting competition at this size was occurring. Laboratory experiments indicated that H. takanoi was a more aggressive competitor for food and, with consistently high abundance on the reefs, may result in some exclusion of C. maenas from their nursery habitat. While total exclusion of C. maenas on the oyster reefs is unlikely, cohabitation may result in reduced population size or increased use of alternative nursery habitats.

Marine Science

African Journals Online (AJOL)

fisheries, recovery and restoration processes, legal and institutional frameworks, and ...... export market for mud crabs from Kenya has increased drastically over the last two decades. ..... The Forest Conservation and Management Act of 2016.

Robotic crabs reveal that female fiddler crabs are sensitive to changes in male display rate.

Science.gov (United States)

Mowles, Sophie L; Jennions, Michael D; Backwell, Patricia R Y

2018-01-01

Males often produce dynamic, repetitive courtship displays that can be demanding to perform and might advertise male quality to females. A key feature of demanding displays is that they can change in intensity: escalating as a male increases his signalling effort, but de-escalating as a signaller becomes fatigued. Here, we investigated whether female fiddler crabs, Uca mjoebergi , are sensitive to changes in male courtship wave rate. We performed playback experiments using robotic male crabs that had the same mean wave rate, but either escalated, de-escalated or remained constant. Females demonstrated a strong preference for escalating robots, but showed mixed responses to robots that de-escalated ('fast' to 'slow') compared to those that waved at a constant 'medium' rate. These findings demonstrate that females can discern changes in male display rate, and prefer males that escalate, but that females are also sensitive to past display rates indicative of prior vigour. © 2018 The Authors.

Intraguild predation by shore crabs affects mortality, behavior, growth, and densities of California horn snails

Science.gov (United States)

Lorda, J.; Hechinger, R.F.; Cooper, S. D.; Kuris, A. M.; Lafferty, Kevin D.

2016-01-01

The California horn snail, Cerithideopsis californica, and the shore crabs, Pachygrapsus crassipesand Hemigrapsus oregonensis, compete for epibenthic microalgae, but the crabs also eat snails. Such intraguild predation is common in nature, despite models predicting instability. Using a series of manipulations and field surveys, we examined intraguild predation from several angles, including the effects of stage-dependent predation along with direct consumptive and nonconsumptive predator effects on intraguild prey. In the laboratory, we found that crabs fed on macroalgae, snail eggs, and snails, and the size of consumed snails increased with predator crab size. In field experiments, snails grew less in the presence of crabs partially because snails behaved differently and were buried in the sediment (nonconsumptive effects). Consistent with these results, crab and snail abundances were negatively correlated in three field surveys conducted at three different spatial scales in estuaries of California, Baja California, and Baja California Sur: (1) among 61 sites spanning multiple habitat types in three estuaries, (2) among the habitats of 13 estuaries, and (3) among 34 tidal creek sites in one estuary. These results indicate that shore crabs are intraguild predators on California horn snails that affect snail populations via predation and by influencing snail behavior and performance.

Biogeochemical interactions among the arsenic, iron, humic substances, and microbes in mud volcanoes in southern Taiwan.

Science.gov (United States)

Liu, Chia-Chuan; Maity, Jyoti Prakash; Jean, Jiin-Shuh; Sracek, Ondra; Kar, Sandeep; Li, Zhaohui; Bundschuh, Jochen; Chen, Chien-Yen; Lu, Hsueh-Yu

2011-01-01

Fluid and mud samples collected from Hsiaokunshui (HKS), Wushanting (WST), Yenshuikeng (YSK), Kunshuiping (KSP), Liyushan (LYS), and Sinyangnyuhu (SYNH) mud volcanoes of southwestern Taiwan were characterized for major ions, humic substances (HS) and trace elements concentrations. The relationship between the release of arsenic (As) and activities of sulfate-reducing bacteria has been assessed to understand relevant geochemical processes in the mud volcanoes. Arsenic (0.02-0.06 mg/L) and humic substances (4.13 × 10(-4) to 1.64 × 10(-3) mM) in the fluids of mud volcanoes showed a positive correlation (r = 0.99, p volcano. Arsenic and iron in mud sediments formed two separate groups i) high As, but low Fe in HKS, WST, and SYNH; and ii) low As, but high Fe in the YSK, KSP, and LYS mud volcanoes. The Eh(S.H.E.) values of the mud volcano liquids were characterized by mild to strongly reducing conditions. The HKS, SYNH, and WST mud volcanoes (near the Chishan Fault) belongs to strong reducing environment (-33 to -116 mV), whereas the LYS, YSK, and KSP mud volcanoes located near the coastal plain are under mild reducing environment (-11 to 172 mV). At low Eh values mud volcanoes, saturation index (SI) values of poorly crystalline phases such as amorphous ferric hydroxide indicate understaturation, whereas saturation is reached in relatively high Eh(S.H.E.) values mud volcanoes. Arsenic contents in sediments are low, presumably due to its release to fluids (As/Fe ratio in YSK, KSP, and LYS sediment: 4.86 × 10(-4)-6.20 × 10(-4)). At low Eh(S.H.E.) values (mild to strong reducing environment), arsenic may co-precipitate with sulfides as a consequence of sulfate reduction (As/Fe ratios in WST, HKS, and SYNH sediments: 0.42-0.69).

Present and Potential Future Distributions of Asian Horseshoe Crabs Determine Areas for Conservation

Directory of Open Access Journals (Sweden)

Stine Vestbo

2018-05-01

Full Text Available Conservation of horseshoe crabs has recently received increasing attention as several populations are in decline. However, scarce information on their distributions in Southeast Asia is impairing conservation efforts. In this study, we sought to improve our understanding of the geographical range and distinct populations of the three Asian horseshoe crabs species in order to identify optimal conservation areas. We mapped the geographic range of Carcinoscorpius rotundicauda, Tachypleus gigas, and T. tridentatus using recent data from field work, literature, Global Biodiversity Information Facility (GBIF, and unpublished data from our scientific network. The data were correlated with 23 different environmental variables of potential ecological importance for horseshoe crabs using the openModeller webservices, including new tidal variables. Ecological niche models were generated using two algorithms, Maximum Entropy and support vector machine, for the three species under present conditions, and projected into a climate change scenario of 2050. The niches of the Asian horseshoe crabs were mostly determined by tidal regime, chlorophyll A concentrations, depth, distance to land, and sea surface temperature. According to our predictions, horseshoe crabs in Southeast Asia are not expected to experience any severe change in extent and distribution of suitable habitat in the future. In order to conserve Asian horseshoe crabs, we suggest establishing Marine Protected Areas at locations where distinct populations and several species occur, such as northern Vietnam, China, Borneo, and southern Japan.

Mobility of 232Th and 210Po in red mud.

Science.gov (United States)

Hegedűs, Miklós; Tóth-Bodrogi, Edit; Jónás, Jácint; Somlai, János; Kovács, Tibor

2018-04-01

The valorization of industrial by-products such as red mud became a tempting opportunity, but the understanding of the risks involved is required for the safe utilization of these products. One of the risks involved are the elevated levels of radionuclides (in the 100-1300 Bq/kg range for both the 238 U and 232  Th decay chains, but usually lower than 1000 Bq/kg, which is the recommended limit for excemption or clearance according to the EU BSS released in 2013) in red mud that can affect human health. There is no satisfactory answer for the utilization of red mud; the main current solution is still almost exclusively disposal into a landfill. For the safe utilization and deposition of red mud, it is important to be able to assess the leaching behaviour of radionuclides. Because there is no commonly accepted measurement protocol for testing the leaching of radionuclides in the EU a combined measurement protocol was made and tested based on heavy metal leaching methods. The leaching features of red mud were studied by methods compliant with the MSZ-21470-50 Hungarian standard, the CEN/TS 14429 standard and the Tessier sequential extraction method for 232 Th and 210 Po. The leached solutions were taken to radiochemical separation followed by spontaneous deposition for Po and electrodeposition for Th. The 332 ± 33 Bq/kg 232 Th content was minimally mobile, 1% became available for distilled water 1% and 6% for Lakanen-Erviö solution; the Tessier extraction showed minimal mobility in the first four steps, while more than 85% remained in the residue. The 210 Po measurements had a severe disturbing effect in many cases, probably due to large amounts of iron present in the red mud, from the 310 ± 12 Bq/kg by aqua regia digestion, distilled water mobilized 23%, while Lakanen-Erviö solution mobilized ∼13%. The proposed protocol is suitable for the analysis of Th and Po leaching behaviour. Copyright © 2018 Elsevier Ltd. All rights reserved.

Line features in the X-ray spectrum of the crab pulsar

International Nuclear Information System (INIS)

Hasinger, G.; Pietsch, W.; Reppin, C.; Truemper, J.; Voges, W.; Kendziorra, E.; Staubert, R.

1982-01-01

Beside the well-known synchrotron behaviour of the Crab pulsar, there may be another source of high energy emission due to a hot plasma. The similarities between this component and common accretion-fed X-ray binaries are the frame in which the present balloon observation of the Crab pulsar will be discussed. (orig./WL)

Biomaterial compounds and bioactivity of horseshoe crab Carsinoscorpius rotundicauda biomass harvested from the Madura Strait

Science.gov (United States)

Asih, Eka Nurrahema Ning; Kawaroe, Mujizat; Bengen, Dietriech G.

2018-03-01

Carsinoscorpius rotundicauda or horseshoe crab biomass has great potential in pharmaceutical aspects, one of them as an antibacterial substance. Information related to the benefits of Carsinoscorpius rotundicauda biomass such as meat and blood is essential because in fact, this species is considered a pest by fishermen, a low market value and has no legal protection in Indonesia. The purpose of this study was to determine the content of biomaterial compounds of meat and bioactivity of Carsinoscorpius rotundicauda plasma on bacterial inhibition from three different stations harvested from the waters in Madura Strait. The observation of the utilization of the potential from horseshoe crab biomass ie meat and plasma was performed by measuring the content of biomaterial compound in horseshoe crab meat by HPLC method and zone of inhibition test for gram-positive and gram-negative bacteria in horseshoe crab plasma. Analysis of the relationship between the two parameters used the Principal Component Analysis. The highest content of biomaterial compounds of monoterpenoid and zoosterol is found in horseshoe crab from Bangkalan waters, namely monoterpenoid (18.33 ppm) and zoosterol (22.67 ppm), while the smallest compound content obtained in horseshoe crab from Probolinggo waters, namely monoterpenoid (13.67) ppm and zoosterol (17.33 ppm). The bioactivity of Dark Blue Plasma (BDP) and Light Blue Plasma (LBP) samples of horseshoe crab obtained around the Madura Strait has the ability to inhibit gram-positive bacteria higher than gram-negative bacteria. The total average of DBP plasma inhibitory power on Staphylococcus aureus was 10.00 mm and 10.07 mm on Bacillus, while that in LBP sample, Staphylococcus aureus was 9.11 mm and Bacillus was 9.67 mm. The high biomaterial compound content of horseshoe crab is in line with the ability of horseshoe crab plasma to inhibit Bacillus and Staphylococcus aureus.

Mating Success of Female Dungeness Crabs (Cancer magister) in Oregon Coastal Waters

DEFF Research Database (Denmark)

Dunn, Paul; Shanks, Alan

2012-01-01

year, and when combined with crabs that carried sperm from previous mating encounters (females store sperm), the percent of females that would have produced viable eggs was 83%. Crabs that definitely molted during the collection year showed higher mating success (95%). The largest females examined...

DID THE CRAB PULSAR UNDERGO A SMALL GLITCH IN 2006 LATE MARCH/EARLY APRIL?

Energy Technology Data Exchange (ETDEWEB)

Vivekanand, M., E-mail: viv.maddali@gmail.com [No. 24, NTI Layout 1st Stage, 3rd Main, 1st Cross, Nagasettyhalli, Bangalore 560094 (India)

2016-08-01

On 2006 August 23 the Crab Pulsar underwent a glitch, which was reported by the Jodrell Bank and the Xinjiang radio observatories. Neither data are available to the public. However, the Jodrell group publishes monthly arrival times of the Crab Pulsar pulse (their actual observations are done daily), and using these, it is shown that about 5 months earlier the Crab Pulsar probably underwent a small glitch, which has not been reported before. Neither observatory discusses the detailed analysis of data from 2006 March to August; either they may not have detected this small glitch, or they may have attributed it to timing noise in the Crab Pulsar. The above result is verified using X-ray data from RXTE . If this is indeed true, this is probably the smallest glitch observed in the Crab Pulsar so far, whose implications are discussed. This work addresses the confusion possible between small-magnitude glitches and timing noise in pulsars.

The bioeconomic impact of different management regulations on the Chesapeake Bay blue crab fishery

Science.gov (United States)

Bunnell, David B.; Lipton, Douglas W.; Miller, Thomas J.

2010-01-01

The harvest of blue crabs Callinectes sapidus in Chesapeake Bay declined 46% between 1993 and 2001 and remained low through 2008. Because the total market value of this fishery has declined by an average of US $ 3.3 million per year since 1993, the commercial fishery has been challenged to maintain profitability. We developed a bioeconomic simulation model of the Chesapeake Bay blue crab fishery to aid managers in determining which regulations will maximize revenues while ensuring a sustainable harvest. We compared 15 different management scenarios, including those implemented by Maryland and Virginia between 2007 and 2009, that sought to reduce female crab harvest and nine others that used seasonal closures, different size regulations, or the elimination of fishing for specific market categories. Six scenarios produced the highest revenues: the 2008 and 2009 Maryland regulations, spring and fall closures for female blue crabs, and 152- and 165-mm maximum size limits for females. Our most important finding was that for each state the 2008 and 2009 scenarios that implemented early closures of the female crab fishery produced higher revenues than the 2007 scenario, in which no early female closures were implemented. We conclude that the use of maximum size limits for female crabs would not be feasible despite their potentially high revenue, given the likelihood that the soft-shell and peeler fisheries cannot be expanded beyond their current capacity and the potentially high mortality rate for culled individuals that are the incorrect size. Our model results support the current use of seasonal closures for females, which permit relatively high exploitation of males and soft-shell and peeler blue crabs (which have high prices) while keeping the female crab harvest sustainable. Further, our bioeconomic model allows for the inclusion of an economic viewpoint along with biological data when target reference points are set by managers.

Effects of mud supply on large-scale estuary morphology and development over centuries to millennia

Directory of Open Access Journals (Sweden)

L. Braat

2017-10-01

Full Text Available Alluvial river estuaries consist largely of sand but are typically flanked by mudflats and salt marshes. The analogy with meandering rivers that are kept narrower than braided rivers by cohesive floodplain formation raises the question of how large-scale estuarine morphology and the late Holocene development of estuaries are affected by cohesive sediment. In this study we combine sand and mud transport processes and study their interaction effects on morphologically modelled estuaries on centennial to millennial timescales. The numerical modelling package Delft3D was applied in 2-DH starting from an idealised convergent estuary. The mixed sediment was modelled with an active layer and storage module with fluxes predicted by the Partheniades–Krone relations for mud and Engelund–Hansen for sand. The model was subjected to a range of idealised boundary conditions of tidal range, river discharge, waves and mud input. The model results show that mud is predominantly stored in mudflats on the side of the estuary. Marine mud supply only influences the mouth of the estuary, whereas fluvial mud is distributed along the whole estuary. Coastal waves stir up mud and remove the tendency to form muddy coastlines and the formation of mudflats in the downstream part of the estuary. Widening continues in estuaries with only sand, while mud supply leads to a narrower constant width and reduced channel and bar dynamics. This self-confinement eventually leads to a dynamic equilibrium in which lateral channel migration and mudflat expansion are balanced on average. However, for higher mud concentrations, higher discharge and low tidal amplitude, the estuary narrows and fills to become a tidal delta.

Experimental Evidence that Abrasion of Carbonate Sand is a Significant Source of Carbonate Mud

Science.gov (United States)

Trower, L.; Kivrak, L.; Lamb, M. P.; Fischer, W. W.

2017-12-01

Carbonate mud is a major sedimentary component of modern and ancient tropical carbonate environments, yet its enigmatic origin remains debated. Early views on the origin of carbonate mud considered the abrasion of carbonate sand during sediment transport as a possible mechanism. In recent decades, however, prevailing thought has generally settled on a binary explanation: 1) precipitation of aragonite needles within the water column, and 2) post-mortem dispersal of biological aragonite, in particular from algae, and perhaps aided by fish. To test these different hypotheses, we designed a model and a set of laboratory experiments to quantify the rates of mud production associated with sediment transport. We adapted a recent model of ooid abrasion rate to predict the rate of mud production by abrasion of carbonate sand as a function of grain size and sediment transport mode. This model predicts large mud production rates, ranging from 103 to 104 g CaCO3/m2/yr for typical grain sizes and transport conditions. These rate estimates are at least one order of magnitude more rapid than the 102 g CaCO3/m2/yr estimates for other mechanisms like algal biomineralization, indicating that abrasion could produce much larger mud fluxes per area as other mechanisms. We tested these estimates using wet abrasion mill experiments; these experiments generated mud through mechanical abrasion of both ooid and skeletal carbonate sand for grain sizes ranging from 250 µm to >1000 µm over a range of sediment transport modes. Experiments were run in artificial seawater, including a series of controls demonstrating that no mud was produced via homogenous nucleation and precipitation in the absence of sand. Our experimental rates match the model predictions well, although we observed small systematic differences in rates between abrasion ooid sand and skeletal carbonate sand that likely stems from innate differences in grain angularity. Electron microscopy of the experimental products revealed

Dependence of radon emanation of red mud bauxite processing wastes on heat treatment

International Nuclear Information System (INIS)

Jobbagy, V.; Somlai, J.; Kovacs, J.; Szeiler, G.; Kovacs, T.

2009-01-01

Natural radioactivity content, radon emanation and some other physical characteristics of red mud were investigated, so that to identify the possibilities of the safe utilization of such material as a building material additive. Based on the radionuclide concentration, red mud is not permitted to be used directly as a building material, however, mixing of a maximum 20% red mud and 80% clay meets the requirements. The main aim of this work was to determine the dependence of the emanation factor of red mud firing temperature and some other parameters. The relevant experimental procedure was carried out in two different ways: without any additional material, and by adding a known amount of sawdust (5-35 wt%) then firing the sample at a given temperature (100-1000 deg. C). The average emanation factor of the untreated dry red mud was estimated to 20%, which decreased to about 5% at a certain heat treatment. Even lower values were found using semi-reductive atmosphere. It has been concluded that all emanation measurements results correlate well to the firing temperature, the specific surface and the pore volume.

Alternatives Analysis Amchitka Island Mud Pit Cap Repair, Amchitka, Alaska January 2016

Energy Technology Data Exchange (ETDEWEB)

Darr, Paul S. [US Department of Energy, Washington, DC (United States). Office of Legacy Management

2016-01-01

The U.S. Department of Energy (DOE) Office of Legacy Management (LM) manages the Nevada Offsites program, which includes a series of reclaimed drilling mud impoundments on Amchitka Island, Alaska (Figure 1). Navarro Research and Engineering, Inc. is the Legacy Management Support contractor (the Contractor) for LM. The Contractor has procured Tetra Tech, Inc. to provide engineering support to the Amchitka mud pit reclamation project. The mud pit caps were damaged during a 7.9-magnitude earthquake that occurred in 2014. The goals of the current project are to investigate conditions at the mud pit impoundments, identify feasible alternatives for repair of the cover systems and the contents, and estimate relative costs of repair alternatives. This report presents descriptions of the sites and past investigations, existing conditions, summaries of various repair/mitigation alternatives, and direct, unburdened, order-of-magnitude (-15% to +50%) associated costs.

Safety evaluation of traces of nickel and chrome in cosmetics: The case of Dead Sea mud.

Science.gov (United States)

Ma'or, Ze'evi; Halicz, Ludwik; Portugal-Cohen, Meital; Russo, Matteo Zanotti; Robino, Federica; Vanhaecke, Tamara; Rogiers, Vera

2015-12-01

Metal impurities such as nickel and chrome are present in natural ingredients-containing cosmetic products. These traces are unavoidable due to the ubiquitous nature of these elements. Dead Sea mud is a popular natural ingredient of cosmetic products in which nickel and chrome residues are likely to occur. To analyze the potential systemic and local toxicity of Dead Sea mud taking into consideration Dead Sea muds' natural content of nickel and chrome. The following endpoints were evaluated: (Regulation No. 1223/20, 21/12/2009) systemic and (SCCS's Notes of Guidance) local toxicity of topical application of Dead Sea mud; health reports during the last five years of commercial marketing of Dead Sea mud. Following exposure to Dead Sea mud, MoS (margin of safety) calculations for nickel and chrome indicate no toxicological concern for systemic toxicity. Skin sensitization is also not to be expected by exposure of normal healthy skin to Dead Sea mud. Topical application, however, is not recommended for already nickel-or chrome-sensitized persons. As risk assessment of impurities present in cosmetics may be a difficult exercise, the case of Dead Sea mud is taken here as an example of a natural material that may contain traces of unavoidable metals. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

A review of fiddler crabs (genus Uca Leach, 1814) in South Africa ...

African Journals Online (AJOL)

Fiddler crabs occur globally across tropical and subtropical coastal habitats including mangrove swamps, which are in decline worldwide. The genus has been well-studied in the Americas, Australia and Asia, whereas information on African species is scarce. This review summarises the existing literature on fiddler crabs ...

Effect of lunar periodicity on the abundance of crabs from the Goa Coast

Digital Repository Service at National Institute of Oceanography (India)

Chatterji, A; Ansari, Z.A; Ingole, B.S.; Sreepada, R.A; Kanti, A; Parulekar, A

Lunar periodicity showed a significant influence on the occurrence of edible crabs (@iPortunus pelagicus, Charybdis cruciata and Portunus sanguinolentus@@). High density of these crabs was recorded in the trawl catches during full moon and new moon...

Impacts of Habitat Complexity on Physiology: Purple Shore Crabs Tolerate Osmotic Stress for Shelter

Science.gov (United States)

McGaw, I. J.

2001-12-01

Purple shore crabs, Hemigrapsus nudus (Crustacea: Decapoda), can survive indefinitely in salinities of 8 (25% SW), but also tolerate short-term exposure to salinities as low as 2. In the laboratory their salinity preference range, determined from choice chamber experiments, is 22-32 and they can discriminate between pairs of salinities separated by a difference of 2. These crabs show a strong positive thigmotaxis and a weak negative phototaxis and tend to choose environments with available shelter. The presence of shelter significantly alters the behaviour of this species. When shelter is available the salinity preference range is 10-32. Even in salinities below this preference range, the presence of shelter prolongs the time spent in the lower test salinities. This change in behaviour has implications on the crab's physiology: the haemolymph osmolality falls to lower levels when crabs remain in low salinity under shelters. In the field, H. nudus is found in creeks with salinities close to freshwater and they may remain in this salinity for up to 11 h, if there are rocks under which to shelter. An increase in habitat complexity increases the number of crabs that are found within the creek. These crabs in the low salinity environment have a lower haemolymph osmolality than crabs on the nearby open shore. In H. nudus the behavioural selection of a shelter appears to outweigh the physiological costs associated with osmotic regulation of the body fluids. Therefore, the distribution of H. nudus in estuaries may depend more on the availability of suitable habitats rather than the salinity tolerance of this species.

Gypsum addition to soils contaminated by red mud: implications for aluminium, arsenic, molybdenum and vanadium solubility.

Science.gov (United States)

Lehoux, Alizée P; Lockwood, Cindy L; Mayes, William M; Stewart, Douglas I; Mortimer, Robert J G; Gruiz, Katalin; Burke, Ian T

2013-10-01

Red mud is highly alkaline (pH 13), saline and can contain elevated concentrations of several potentially toxic elements (e.g. Al, As, Mo and V). Release of up to 1 million m(3) of bauxite residue (red mud) suspension from the Ajka repository, western Hungary, caused large-scale contamination of downstream rivers and floodplains. There is now concern about the potential leaching of toxic metal(loid)s from the red mud as some have enhanced solubility at high pH. This study investigated the impact of red mud addition to three different Hungarian soils with respect to trace element solubility and soil geochemistry. The effectiveness of gypsum amendment for the rehabilitation of red mud-contaminated soils was also examined. Red mud addition to soils caused a pH increase, proportional to red mud addition, of up to 4 pH units (e.g. pH 7 → 11). Increasing red mud addition also led to significant increases in salinity, dissolved organic carbon and aqueous trace element concentrations. However, the response was highly soil specific and one of the soils tested buffered pH to around pH 8.5 even with the highest red mud loading tested (33 % w/w); experiments using this soil also had much lower aqueous Al, As and V concentrations. Gypsum addition to soil/red mud mixtures, even at relatively low concentrations (1 % w/w), was sufficient to buffer experimental pH to 7.5-8.5. This effect was attributed to the reaction of Ca(2+) supplied by the gypsum with OH(-) and carbonate from the red mud to precipitate calcite. The lowered pH enhanced trace element sorption and largely inhibited the release of Al, As and V. Mo concentrations, however, were largely unaffected by gypsum induced pH buffering due to the greater solubility of Mo (as molybdate) at circumneutral pH. Gypsum addition also leads to significantly higher porewater salinities, and column experiments demonstrated that this increase in total dissolved solids persisted even after 25 pore volume replacements. Gypsum

Trophic discrimination of stable isotopes and potential food source partitioning by leaf-eating crabs in mangrove environments

DEFF Research Database (Denmark)

Kristensen, Erik; Lee, Shing Yip; Mangion, Perrine

2017-01-01

Diet composition of leaf-eating mangrove crabs is a puzzle among mangrove ecologists. Nutrient-poor leaf litter can in most cases not support animal growth. Food partitioning (mangrove leaves, animal tissue, and microphytobenthos [MPB]) of sesarmid and ucidid mangrove crabs from eight locations...... here for crabs foraging on leaf litter to identify discrimination values that provide a balanced diet with sufficient nutrients (i.e., N) when combined with other food sources. The data from all mangrove locations suggest that sesarmid and ucidid crabs ingest and assimilate mixtures of available food...... is probably caused by metabolic disparities between these two crab families. Deviations in 15N discrimination have in most cases only minor influence on the model-based 13C discrimination thresholds. The present findings lead us to suggest a modified Optimal Foraging Theory for leaf-eating mangrove crabs....

Use of Hyperspectral Imagery to Assess Cryptic Color Matching in Sargassum Associated Crabs.

Directory of Open Access Journals (Sweden)

Brandon J Russell

Full Text Available Mats of the pelagic macroalgae Sargassum represent a complex environment for the study of marine camouflage at the air-sea interface. Endemic organisms have convergently evolved similar colors and patterns, but quantitative assessments of camouflage strategies are lacking. Here, spectral camouflage of two crab species (Portunus sayi and Planes minutus was assessed using hyperspectral imagery (HSI. Crabs matched Sargassum reflectance across blue and green wavelengths (400-550 nm and diverged at longer wavelengths. Maximum discrepancy was observed in the far-red (i.e., 675 nm where Chlorophyll a absorption occurred in Sargassum and not the crabs. In a quantum catch color model, both crabs showed effective color matching against blue/green sensitive dichromat fish, but were still discernible to tetrachromat bird predators that have visual sensitivity to far red wavelengths. The two species showed opposing trends in background matching with relation to body size. Variation in model parameters revealed that discrimination of crab and background was impacted by distance from the predator, and the ratio of cone cell types for bird predators. This is one of the first studies to detail background color matching in this unique, challenging ecosystem at the air-sea interface.

Mariana Forearc Serpentine Mud Volcanoes Harbor Novel Communities of Extremophilic Archaea

Science.gov (United States)

Curtis, A. C.; Moyer, C. L.

2005-12-01

Since the Eocene (45 Ma) the Pacific Plate has been subducting beneath the Philippine Plate in the western Pacific ocean. This process has given rise to the Mariana Islands. As a direct result of this non-accretionary subduction, the Mariana Island Arc contains a broad forearc zone of serpentinite mud volcanoes located between the island chain and the trench. Forearc faulting, due to high pressure and low temperature build-up, produce slurries of mud and rock that mix with slab derived fluids and rise in conduits. Due to dehydration of the overlying mantle, native rock is converted to serpentinite, which squeezes out at fractures along the sea floor. This results in giant mud volcanoes (~30 km diameter and ~2 km high) that form a chain between 50 and 150 km behind the trench axis. Microbial samples were collected using Jason II from seven mud volcanoes along the length of the forearc and community fingerprinting was applied to genomic DNA using terminal restriction length polymorphism (T-RFLP). The resulting data were compared with traditional clone library and sequence analysis from samples obtained from the southernmost mud volcano, South Chamorro, site 1200, holes D and E, sampled during ODP Leg 195. The dominant archaeal phylotypes found clustered into two groups within the Methanobacteria, a class of anaerobic methanogens and methylotrophs. These phylotypes were detected at three of the seven mud volcanoes sampled and comprised 61% of the archaeal clone library from 1200 E. The first group was most closely related to the order Methanobacteriales, however, these novel phylotypes had similarity values of up to 0.90 at best with some resulting at 0.48. The second novel group of phylotypes were most closely related to order Methanosarcinales, with similarity values in the range of 0.50 to 0.22, indicating a relatively weak association with known phylotypes. At 1200 D, phylotypes associated with non-thermophilic Marine Group I Crenarchaeota were detected

Crab and shellfish occurrences in the newly-grown mangrove habitats in southern Thailand

Science.gov (United States)

Yeesin, P.; Bautip, S.; Chesoh, S.

2018-04-01

Mangrove crabs and shellfish populating in Prince of Songkla University’s new grown mangrove forest were investigated from January 2011 to December 2011 and then repeated annually. A total of 12 species under 6 families of crab and 11 species under 5 families of shellfish were recorded. The most abundant family of crab was Sesarmidae (64.18 %), followed by Ocypodidae, Varunidae, Macrophthalmidae, Portunidae and Dotillidae. Episesarma mederi ( H. Milne Edwards, 1853) showed highest dominant species. In addition, the most dominant family of shellfish was Potamididae (13.79 %), followed by Melampidae, Assimineidae, Onchidiidae and Littorinidae. Sea snail (Cerithidae quadrata; Sowerby, 1866) presented the most dominant coastal mollusc species. Abundance and diversification crabs and mollusks show important component of food web of this type ecosystem. However, only trapped hold samples during low tide were collected but this preliminary finding enables reasonable specified regulation measures.

Understanding to Hierarchical Microstructures of Crab (Chinese hairy) Shell as a Natural Architecture

Energy Technology Data Exchange (ETDEWEB)

Chuanqiang, Zhou [Testing Center, Yangzhou University, No. 48 Wenhui East Road, Yangzhou (China); Xiangxiang, Gong [Testing Center, Yangzhou University, No. 48 Wenhui East Road, Yangzhou (China); School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou (China); Jie, Han [School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou (China)

2016-03-07

This work was done to better understand the microstructures, composition and mechanical properties of Chinese hairy crab shell. For fully revealing its hierarchical microstructure, the crab shell was observed with electron microscope under different magnifications from different facets. XRD, EDS, FTIR and TGA techniques have been used to characterize the untreated and chemically-treated crab shells, which provided enough information to determine the species and relative content of components in this biomaterial. Combined the microstructures with constituents analysis, the structural principles of crab shell was detailedly realized from different structural levels beyond former reports. To explore the relationship between structure and function, the mechanical properties of shell have been measured through performing tensile tests. The contributions of organics and minerals in shell to the mechanical properties were also discussed by measuring the tensile strength of de-calcification samples treated with HCl solution.

Understanding to Hierarchical Microstructures of Crab (Chinese hairy) Shell as a Natural Architecture

International Nuclear Information System (INIS)

Chuanqiang, Zhou; Xiangxiang, Gong; Jie, Han

2016-01-01

This work was done to better understand the microstructures, composition and mechanical properties of Chinese hairy crab shell. For fully revealing its hierarchical microstructure, the crab shell was observed with electron microscope under different magnifications from different facets. XRD, EDS, FTIR and TGA techniques have been used to characterize the untreated and chemically-treated crab shells, which provided enough information to determine the species and relative content of components in this biomaterial. Combined the microstructures with constituents analysis, the structural principles of crab shell was detailedly realized from different structural levels beyond former reports. To explore the relationship between structure and function, the mechanical properties of shell have been measured through performing tensile tests. The contributions of organics and minerals in shell to the mechanical properties were also discussed by measuring the tensile strength of de-calcification samples treated with HCl solution

Ethnotaxonomical Study of Mole Crab (Crustacea:Hippoidea on Coastal Community of Cilacap

Directory of Open Access Journals (Sweden)

Dian Bhagawati

2016-09-01

Full Text Available Local wisdom is a cultural heritage that needs to be preserved. The Cilacap’s coastal communities have traditional taxonomy knowledge that hasn’t been informed, especially about mole crab. This study aimed to explore the ethnotaxonomy knowledge of sand crabs (Crustacea: Hippoidea in Widarapayung coastal communities. The purposive snowball sampling was used for the method, followed by observation and semi-structured interviews with 30 respondents. Data were analyzed descriptively based on observations and interviews. The results showed that the coastal communities in Widarapayung tourist areas could be divided into five groups, namely catchers, collectors, processors, traders, and consumers. The catcher was able to recognize and describe three types of sand crabs based on the shape of the body and their catchment areas. Captured crabs had the local name of ‘yutuk jambe’ (Emerita emeritus Linnaeus 1767, the appellation was based on carapace shape that resembled the shape of areca fruit; ‘Yutuk bathok’ (Hippa adactyla Fabricius 1787, had the carapace shape resembling a coconut shell, and ‘yutuk Kethek’ (Albunea symmysta Linnaeus 1758, had ornaments on the carapace surface similar with a monkey face, there were dense setae on the edge of the carapace, spiny long antennas and aggressively pinch when captured. The knowledge and skills of sand crabs classification and local name entitlement acquired by the people were in accordance with the Berlin’s model. How to CiteBhagawati, D., Anggoro, S., Zainuri, M. & Sya’rani, L. (2016. Ethnotaxonomical Study of Mole Crab (Crustacea:Hippoidea on Coastal Community of Cilacap. Biosaintifika: Journal of Biology & Biology Education, 8(2, 222-230.

Red mud enhances methanogenesis with the simultaneous improvement of hydrolysis-acidification and electrical conductivity.

Science.gov (United States)

Ye, Jie; Hu, Andong; Ren, Guoping; Zhou, Ting; Zhang, Guangming; Zhou, Shungui

2018-01-01

The role of red mud in the improvement of methanogenesis during sludge anaerobic digestion was innovatively investigated in this study. The results demonstrated that the addition of 20g/L red mud resulted in a 35.5% increase in methane accumulation. Red mud effectively promoted the hydrolysis-acidification of organic compounds in the sludge, which resulted in the increase of protein, polysaccharide, and VFAs by 5.1-94.5%. The activities of key enzymes were improved by 41.4-257.3%. Electrochemical measurements presented direct evidence that the electrical conductivity was significantly improved with red mud. More conductive magnetite was formed during the secondary mineralization after Fe(III) reduction by Fe (III)-reducing genes such as Clostridiaceae and Ruminococcaceae. The higher conductivity enhanced the electron transfer between the syntrophic bacteria (Geobacteraceae) and methanogens (Methanosaeta and Methanosarcina), and then improved the methanogenesis. This research provides a novel perspective on the synergism between sludge and red mud for methane production. Copyright © 2017 Elsevier Ltd. All rights reserved.

76 FR 36511 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3

Science.gov (United States)

2011-06-22

...-BA22 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3 AGENCY... the Atlantic Deep-Sea Red Crab Fishery Management Plan (FMP) (Amendment 3), incorporating a draft... current trap limit regulations state that red crab may not be harvested from gear other than a marked red...

Evaluation of red mud as pozzolanic material in replacement of cement for production of mortars

International Nuclear Information System (INIS)

Manfroi, E.P.; Cheriaf, M.; Rocha, J.C.

2010-01-01

Red mud is a by-product of the alkaline extraction of aluminum from the bauxite and represents a renewed environmental problem due the significant annual throughput by the plants. In the present work, the pozzolanic properties of Brazilian red mud fired at 600, 700, 800 and 900 deg C were investigated by monitoring lime consumption using DTA analysis and Brazilian standard methodology NBR 5772 (1992). Products and kinetics of hydration were determined in cement pastes produced with 5 and 15% red mud using x-ray diffraction and DTA analysis. Compressive strength and capillary absorption tests were realized on mortars constituted by 5, 10 and 15% red mud in replacement of cement. When calcined at 600 deg C, the red mud develops good pozzolanic properties, and the compressive strength of mortars produced with this waste meet values in accordance with regulatory standard. These results shown than red mud can be used, in partial replacement of cement, as new construction material to produce sustainable mortars with low environmental impact. (author)

The Dead Sea Mud and Salt: A Review of Its Characterization, Contaminants, and Beneficial Effects

Science.gov (United States)

Bawab, Abeer Al; Bozeya, Ayat; Abu-Mallouh, Saida; Abu Irmaileh, Basha'er; Daqour, Ismail; Abu-Zurayk, Rund A.

2018-02-01

The Dead Sea has been known for its therapeutic and cosmetic properties. The unique climatic conditions in the Dead Sea area make it a renowned site worldwide for the field of climatotherapy, which is a natural approach for the provision of medications for many human diseases including unusual exclusive salt composition of the water, a special natural mud, thermal mineral springs, solar irradiation, oxygen-rich and bromine-rich haze. This review focuses on the physical, chemical, and biological characteristics of the Dead Sea mud and salts, in addition to their contaminants, allowing this review to serve as a guide to interested researchers to their risks and the importance of treatment. Beneficial effects of Dead Sea mud and salts are discussed in terms of therapy and cosmetics. Additional benefits of both Dead Sea mud and salts are also discussed, such as antimicrobial action of the mud in relation to its therapeutic properties, and the potency of mud and salts to be a good medium for the growth of a halophilic unicellular algae, used for the commercial production of β-carotene Dunaliella.

Biodiesel Production from Castor Oil by Using Calcium Oxide Derived from Mud Clam Shell

OpenAIRE

Ismail, S.; Ahmed, A. S.; Anr, Reddy; Hamdan, S.

2016-01-01

The catalytic potential of calcium oxide synthesized from mud clam shell as a heterogeneous catalyst for biodiesel production was studied. The mud clam shell calcium oxide was characterized using particle size analyzer, Fourier transform infrared spectroscopy, scanning electron microscopy, and BET gas sorption analyzer. The catalyst performance of mud clam shell calcium oxide was studied in the transesterification of castor oil as biodiesel. Catalyst characterization and transesterification s...

New technology of extracting the amount of rare earth metals from the red mud

International Nuclear Information System (INIS)

Martoyan, G A; Karamyan, G G; Vardan, G A

2016-01-01

The paper outlined the environmental and economic problems associated with red mud - the waste generated in processing of bauxite ore for aluminum production. The chemical analysis of red mud has identified a number of useful elements including rare earth metals. The electromembrane technology of red mud processing with extraction of valuable elements is described. A possible scheme of separation of these metals through electrolysis is also given. (paper)

Environmental impact of toxic elements in red mud studied by fractionation and speciation procedures.

Science.gov (United States)

Milačič, Radmila; Zuliani, Tea; Ščančar, Janez

2012-06-01

Aluminum (Al) is mostly produced from bauxite ore, which contains up to 70% of Al(2)O(3) (alumina). Before alumina is refined to aluminum metal, it is purified by hot alkaline extraction. As a waste by-product red mud is formed. Due to its high alkalinity and large quantities, it represents a severe disposal problem. In Kidričevo (Slovenia), red mud was washed with water before disposal, and after drying, covered with soil. In Ajka (Hungary), the red mud slurry was collected directly in a containment structure, which burst caused a major accident in October 2010. In the present work the environmental impact of toxic elements in red mud from Kidričevo and Ajka were evaluated by applying a sequential extraction procedure and speciation analysis. The predominant red mud fraction was the insoluble residue; nevertheless, environmental concern was focused on the highly mobile water-soluble fraction of Al and Cr. Al in the water-soluble Ajka mud fraction was present exclusively in form of toxic [Al(OH)(4)](-), while Cr existed in its toxic hexavalent form. Comparative assessment to red mud from Kidričevo (Slovenia) with a lower alkalinity (pH 9) with that from Ajka demonstrated significantly lower Al solubility and the presence of only trace amounts of Cr(VI), confirming that disposal of neutralized mud is environmentally much more acceptable and carries a smaller risk of ecological accidents. Since during the Ajka accident huge amounts of biologically available Al and moderate Cr(VI) concentrations were released into the terrestrial and aquatic environments, monitoring of Al and Cr(VI) set free during remedial actions at the contaminated site is essential. Particular care should be taken to minimize the risk of release of soluble Al species and Cr(VI) into water supplies and surface waters. Copyright © 2012 Elsevier B.V. All rights reserved.

Field evaluation of in situ remediation of a heavy metal contaminated soil using lime and red-mud

Energy Technology Data Exchange (ETDEWEB)

Gray, C.W. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Dunham, S.J. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Dennis, P.G. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Zhao, F.J. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); McGrath, S.P. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom)]. E-mail: steve.mcgrath@bbsrc.ac.uk

2006-08-15

We evaluated the effectiveness of lime and red mud (by-product of aluminium manufacturing) to reduce metal availability to Festuca rubra and to allow re-vegetation on a highly contaminated brown-field site. Application of both lime and red mud (at 3 or 5%) increased soil pH and decreased metal availability. Festuca rubra failed to establish in the control plots, but grew to a near complete vegetative cover on the amended plots. The most effective treatment in decreasing grass metal concentrations in the first year was 5% red mud, but by year two all amendments were equally effective. In an additional pot experiment, P application in combination with red mud or lime decreased the Pb concentration, but not total uptake of Pb in Festuca rubra compared to red mud alone. The results show that both red mud and lime can be used to remediate a heavily contaminated acid soil to allow re-vegetation. - Red mud was effective in immobilising heavy metals in soil.

Field evaluation of in situ remediation of a heavy metal contaminated soil using lime and red-mud

International Nuclear Information System (INIS)

Gray, C.W.; Dunham, S.J.; Dennis, P.G.; Zhao, F.J.; McGrath, S.P.

2006-01-01

We evaluated the effectiveness of lime and red mud (by-product of aluminium manufacturing) to reduce metal availability to Festuca rubra and to allow re-vegetation on a highly contaminated brown-field site. Application of both lime and red mud (at 3 or 5%) increased soil pH and decreased metal availability. Festuca rubra failed to establish in the control plots, but grew to a near complete vegetative cover on the amended plots. The most effective treatment in decreasing grass metal concentrations in the first year was 5% red mud, but by year two all amendments were equally effective. In an additional pot experiment, P application in combination with red mud or lime decreased the Pb concentration, but not total uptake of Pb in Festuca rubra compared to red mud alone. The results show that both red mud and lime can be used to remediate a heavily contaminated acid soil to allow re-vegetation. - Red mud was effective in immobilising heavy metals in soil

Sterol biosynthesis from acetate and the fate of dietary cholesterol and desmosterol in crabs

International Nuclear Information System (INIS)

Teshima, Shin-ichi; Kanazawa, Akio; Okamoto, Haruhito

1976-01-01

This paper deals with the sterol-synthesizing ability and the fate of dietary sterols, cholesterol and desmosterol, in the crabs, Sesarma dehaani and Helice tridens. Injected acetate-1- 14 C was not incorporated into either squalene or sterols in the above crabs. This suggested that the sterol-synthesizing ability from acetate is absent or weak in the crabs, S. dehaani and H. tridens. The apparent percentage absorptions of dietary cholesterol and desmosterol from the digestive tracts were 91.9 and 90.9, respectively. The ingested cholesterol and desmosterol were metabolized to steryl esters and polar compounds but only slightly to water-soluble sterols. Also, it was shown that the crab, S. dehaani, is capable of converting desmosterol to cholesterol. (auth.)

Appearance and partial purification of a high molecular weight protein in crabs exposed to saxitoxin.

Science.gov (United States)

Barber, K G; Kitts, D D; Townsley, P M; Smith, D S

1988-01-01

This paper provides evidence for a protein component which appears to be involved in the seasonal resistance of small shore crabs, Hemigrapsus oregonesis and Hemigrapsus nudus to saxitoxin, a principle neurotoxin involved in paralytic shellfish poisoning (PSP). This unique protein complex was isolated and partially purified by ion exchange chromatography using DEAE-cellulose from visceral tissue extracts of resistant crabs. The complex was absent in control crabs that were sensitive to saxitoxin. In addition, the protein complex was induced in the crab after acute administration of low doses of saxitoxin. Results indicate that the protein complex is acidic in nature and has an apparent mol. wt of 145,000.

Consumption patterns and risk assessment of crab consumers from the Newark Bay Complex, New Jersey, USA.

Science.gov (United States)

Pflugh, Kerry Kirk; Stern, Alan H; Nesposudny, Laura; Lurig, Lynette; Ruppel, Bruce; Buchanan, Gary A

2011-10-01

The Newark Bay Complex (NBC) is a significant historical repository of polychlorinated dibenzodioxins (PCDDs) and dioxin-like compounds. Detection of high levels of 2,3,7,8 tetrachloro-dibenzodioxins (TCDD) and its toxicological equivalents in blue crabs in the early 1990's led to a ban on the taking and distribution of crabs from the NBC. Despite this ban and ongoing communication outreach, surveys of crabbers in 1995, 2002 and 2005 by the New Jersey Department of Environmental Protection (NJDEP) showed that crabbing for recreational purposes and for significant dietary supplementation was continuing. At the time they were surveyed, the crabbers had been consuming these crabs for an average of 37% of their lives. Thus, exposure can be considered chronic. The surveys provided data on the duration, frequency and amount of NBC crab consumption. In 2004, the NJDEP sampled blue crabs in the NBC and analyzed the edible portions for 2,3,7,8 TCDD toxicity equivalent (TEQ) concentration. We have combined the survey-based exposure data and the 2,3,7,8 TCDD TEQ concentration data to produce an estimate of the lifetime cancer risk to NBC crabbers from dioxin-like compounds. We employed a point-estimate approach using discrete lower, central tendency and reasonable maximum exposure (RME) estimates of exposure factors and a probabilistic approach to exposure factors. Both approaches show central tendency lifetime cancer risk of greater than one-in-a-thousand (10(-3)) and an upper percentile/RME risk of approximately one-in-a-hundred (10(-2)). Little extrapolation is involved in applying the 2,3,7,8-TCDD TEQ concentration data in crabs to risk estimates in the population consuming those crabs. The ongoing and frequent nature of the crab collection minimizes the uncertainty often inherent in food recall surveys. These estimates point to the continued risk posed to NBC crab consumers and to the continuing importance of this resource which, with proper remediation, could provide

Infection of juvenile edible crabs, Cancer pagurus by a haplosporidian-like parasite.

Science.gov (United States)

Thrupp, Tara J; Lynch, Sharon A; Wootton, Emma C; Malham, Shelagh K; Vogan, Claire L; Culloty, Sarah C; Rowley, Andrew F

2013-09-01

This study aimed to examine the pathobiology of a haplosporidian-like infection in juvenile (pre-recruit) edible crabs (Cancer pagurus) from two locations in South West Wales, UK. Infected crabs showed no external symptoms of the disease but dissection revealed an infected and hypertrophic antennal gland. Histological examination showed extensive parasitisation of the antennal gland overlying the hepatopancreas. Heavily infected crabs also showed the presence of parasites with morphological similarities to Haplosporidia in the labyrinth of the antennal gland and in the gills. The spread of the infection from the antennal gland to the gills suggests that these parasites are released into the haemolymph. Attempts to characterise the haplosporidian-like organism using several primers previously shown to amplify members of the phylum Haplosporidia failed. The prevalence of infection in juvenile edible crabs varied throughout the sampling period of November 2011 to July 2012 with the lowest level of ca. 15% in November peaking at 70% in March. This parasite may represent a threat to the sustainability of edible crab fisheries in this region if the damage observed in the antennal gland and gills results in host mortality. The identification of these parasites as members of the phylum Haplosporidia based on morphology alone must be seen as tentative in the absence of sequence data. Copyright © 2013 Elsevier Inc. All rights reserved.

Sequential extraction applied to Peruibe black mud, SP, Brazil

International Nuclear Information System (INIS)

Torrecilha, Jefferson Koyaishi

2014-01-01

The Peruibe Black mud is used in therapeutic treatments such as psoriasis, peripheral dermatitis, acne and seborrhoea, as well as in the treatment of myalgia, arthritis, rheumatism and non-articular processes. Likewise other medicinal clays, it may not be free from possible adverse health effects due to possible hazardous minerals leading to respiratory system occurrences and other effects, caused by the presence of toxic elements. Once used for therapeutic purposes, any given material should be fully characterized and thus samples of Peruibe black mud were analyzed to determine physical and chemical properties: moisture content, organic matter and loss on ignition; pH, particle size, cation exchange capacity and swelling index. The elemental composition was determined by Neutron Activation Analysis, Atomic Absorption Graphite Furnace and X-ray fluorescence; the mineralogical composition was determined by X-ray diffraction. Another tool widely used to evaluate the behavior of trace elements, in various environmental matrices, is the sequential extraction. Thus, a sequential extraction procedure was applied to fractionate the mud in specific geochemical forms and verify how and how much of the elements may be contained in it. Considering the several sequential extraction procedures, BCR-701 method (Community Bureau of Reference) was used since it is considered the most reproducible among them. A simple extraction with an artificial sweat was, also, applied in order to verify which components are potentially available for absorption by the patient skin during the topical treatment. The results indicated that the mud is basically composed by a silty-clay material, rich in organic matter and with good cation exchange capacity. There were no significant variations in mineralogy and elemental composition of both, in natura and mature mud forms. The analysis by sequential extraction and by simple extraction indicated that the elements possibly available in larger

A nonlinear model for the fluidization of marine mud by waves

Energy Technology Data Exchange (ETDEWEB)

Foda, M.A.; Hunt, J.R.; Chou, Hsien-Ter (Univ. of California, Berkeley (United States))

1993-04-15

The authors consider the problem of fluidization of mud deposits in shallow waters due to interactions with water waves. This is of increasing interest because of concerns that water pollutants, including heavy metals, pesticides, etc., are often found near surfaces of mud deposits. The authors look at the question of whether the cohesive properties of mud deposits exhibit nonlinear properties when they experience strains from water wave interactions. It is obvious that with large enough wave interactions the deposits become fluidized, and are not in that case truly nonlinear. In their modeling efforts they try to incorporate these ideas into a cohesive model where the magnitude of the water wave-sediment interaction has an influence on the type of response within the system.

Mechanism of red mud combined with Fenton's reagent in sewage sludge conditioning.

Science.gov (United States)

Zhang, Hao; Yang, Jiakuan; Yu, Wenbo; Luo, Sen; Peng, Li; Shen, Xingxing; Shi, Yafei; Zhang, Shinan; Song, Jian; Ye, Nan; Li, Ye; Yang, Changzhu; Liang, Sha

2014-08-01

Red mud was evaluated as an alternative skeleton builder combined with Fenton's reagent in sewage sludge conditioning. The results show that red mud combined with Fenton's reagent showed good conditioning capability with the pH of the filtrate close to neutrality, indicating that red mud acted as a neutralizer as well as a skeleton builder when jointly used with Fenton's reagent. Through response surface methodology (RSM), the optimal dosages of Fe(2+), H2O2 and red mud were proposed as 31.9, 33.7 and 275.1 mg/g DS (dry solids), respectively. The mechanism of the composite conditioner could be illuminated as follows: (1) extracellular polymeric substances (EPS), including loosely bound EPS and tightly bound EPS, were degraded into dissolved organics, e.g., proteins and polysaccharides; (2) bound water was released and converted into free water due to the degradation of EPS; and (3) morphology of the conditioned sludge exhibited a porous structure in contrast with the compact structure of raw sludge, and the addition of red mud formed new mineral phases and a rigid lattice structure in sludge, allowing the outflow of free water. Thus, sludge dewatering performance was effectively improved. The economic assessment for a wastewater treatment plant of 370,000 equivalent inhabitants confirms that using red mud conditioning, combined with Fenton's reagent, leads to a saving of approximately 411,000 USD/y or 50.8 USD/t DS comparing with using lime and ordinary Portland cement combined with Fenton's reagent, and approximately 612,000 USD/y or 75.5 USD/t DS comparing with the traditional treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Propagation of Measurement-While-Drilling Mud Pulse during High Temperature Deep Well Drilling Operations

OpenAIRE

Li, Hongtao; Meng, Yingfeng; Li, Gao; Wei, Na; Liu, Jiajie; Ma, Xiao; Duan, Mubai; Gu, Siman; Zhu, Kuanliang; Xu, Xiaofeng

2013-01-01

Signal attenuates while Measurement-While-Drilling (MWD) mud pulse is transmited in drill string during high temperature deep well drilling. In this work, an analytical model for the propagation of mud pulse was presented. The model consists of continuity, momentum, and state equations with analytical solutions based on the linear perturbation analysis. The model can predict the wave speed and attenuation coefficient of mud pulse. The calculated results were compared with the experimental dat...

American alligator digestion rate of blue crabs and its implications for stomach contents analysis

Science.gov (United States)

Nifong, James C.; Rosenblatt, Adam E.; Johnson, Nathan A.; Barichivich, William; Silliman, Brian; Heithaus, Michael R.

2012-01-01

Stomach contents analysis (SCA) provides a snap-shot observation of a consumer's diet. Interpretation of SCA data can be complicated by many factors, including variation in gastric residence times and digestion rates among prey taxa. Although some SCA methods are reported to efficiently remove all stomach contents, the effectiveness of these techniques has rarely been tested for large irregular shaped prey with hard exoskeletons. We used a controlled feeding trial to estimate gastric residency time and decomposition rate of a large crustacean prey item, the Blue Crab (Callinectes sapidus), which is consumed by American Alligators (Alligator mississippiensis), an abundant apex predator in coastal habitats of the southeastern United States. The decomposition rate of C. sapidus in the stomachs of A. mississippiensis followed a predictable pattern, and some crab pieces remained in stomachs for at least 14 days. We also found that certain portions of C. sapidus were prone to becoming caught within the stomach or esophagus, meaning not all crab parts are consistently recovered using gastric lavage techniques. However, because the state of decomposition of crabs was predictable, it is possible to estimate time since consumption for crabs recovered from wild alligators. This information, coupled with a detailed understanding of crab distributions and alligator movement tactics could help elucidate patterns of cross-ecosystem foraging by the American Alligator in coastal habitats

Effect of formulation variables on the physical properties and stability of Dead Sea mud masks.

Science.gov (United States)

Shahin, Sawsan; Hamed, Saja; Alkhatib, Hatim S

2015-01-01

The physical stability of Dead Sea mud mask formulations under different conditions and their rheological properties were evaluated as a function of the type and level of thickeners, level of the humectant, incorporation of ethanol, and mode of mud treatment. Formulations were evaluated in terms of visual appearance, pH, moisture content, spreadability, extrudability, separation, rate of drying at 32 degrees C, and rheological properties. Prepared mud formulations and over-the-shelf products showed viscoplastic shear thinning behavior; satisfactory rheological behavior was observed with formulations containing a total concentration of thickeners less than 10% (w/w). Casson and Herschel-Bulkley models were found the most suitable to describe the rheological data of the prepared formulations. Thickener incorporation decreased phase separation and improved formulation stability. Bentonite incorporation in the mud prevented color changes during stability studies while glycerin improved spreadability. Addition of 5% (w/w) ethanol improved mud extrudability, slightly increased percent separation, accelerated drying at 32 degrees C, and decreased viscosity and yield stress values. Different mud treatment techniques did not cause a clear behavioral change in the final mud preparation. B10G and K5B5G were labeled as "best formulas" based on having satisfactory physical and aesthetic criteria investigated in this study, while other formulations failed in one or more of the tests we have performed.

Spatial and temporal patterns of subtidal and intertidal crabs excursions

Science.gov (United States)

Silva, A. C. F.; Boaventura, D. M.; Thompson, R. C.; Hawkins, S. J.

2014-01-01

Highly mobile predators such as fish and crabs are known to migrate from the subtidal zone to forage in the intertidal zone at high-tide. The extent and variation of these habitat linking movements along the vertical shore gradient have not been examined before for several species simultaneously, hence not accounting for species interactions. Here, the foraging excursions of Carcinus maenas (L.), Necora puber (Linnaeus, 1767) and Cancer pagurus (Linnaeus, 1758) were assessed in a one-year mark-recapture study on two replicated rocky shores in southwest U.K. A comparison between the abundance of individuals present on the shore at high-tide with those present in refuges exposed at low-tide indicated considerable intertidal migration by all species, showing strong linkage between subtidal and intertidal habitats. Estimates of population size based on recapture of marked individuals indicated that an average of ~ 4000 individuals combined for the three crab species, can be present on the shore during one tidal cycle. There was also a high fidelity of individuals and species to particular shore levels. Underlying mechanisms for these spatial patterns such as prey availability and agonistic interactions are discussed. Survival rates were estimated using the Cormack-Jolly-Seber model from multi-recapture analysis and found to be considerably high with a minimum of 30% for all species. Growth rates were found to vary intraspecifically with size and between seasons. Understanding the temporal and spatial variations in predation pressure by crabs on rocky shores is dependent on knowing who, when and how many of these commercially important crab species depend on intertidal foraging. Previous studies have shown that the diet of these species is strongly based on intertidal prey including key species such as limpets; hence intertidal crab migration could be associated with considerable impacts on intertidal assemblages.

AFSC/RACE/SAP/Long: Data from: Embryo development in golden king crab, Lithodes aequispina.

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The data from this study, describes embryo development in Golden king crab, Lithodes aequispinus. Six female multiparous golden king crab were captured from the...

Sex Ratio And Size At First Maturity Of Blue Swimming Crab (Portunus pelagicus Salemo Island Pangkep Regency

Directory of Open Access Journals (Sweden)

Muh. Saleh Nurdin

2016-03-01

Full Text Available Blue swimming crab (Portunuspelagicus is aeconomical valuable fisheries importantcommodity  due to the high demand and availability jobs created for the fishermen. Due to their high demand blue swimming crab heavily exploited from Salemo Island. This study aimed at comparing the sex ratio and the size at first maturity of blue swimming crab caught in mangrove ecosystems, coral reefs, and seagrass. Sex ratio was analyzed using chi square test and the size at first maturity was analyzed using the Spearman-Karber formula. The results showed the sex ratio ofmales and femalessmall crab caught in every ecosystem is balanced. The size at first maturity of blue swimming crab caught in mangrove, seagrass and coral reefs, each to the male 81,08 mm, 102,36 mm and 102,87 mm in width and size of female 94,54 mm, 83,35 mm, 98,31 mm width. In a reference to government regulations, the blue male swimming crab caught in the coral reef and seagrass ecosystems have yet to size at first maturity is allowed to be captured. Keywords: blue swimming crab, sex ratio,size at first maturity, Salemo Island

75 FR 7435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Science.gov (United States)

2010-02-19

.... 100105009-0053-01] RIN 0648-AY51 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications AGENCY: National Marine Fisheries Service (NMFS... comments. SUMMARY: NMFS proposes 2010 specifications for the Atlantic deep-sea red crab fishery, including...

Evolution of crabs – history and deconstruction of a prime example of convergence

NARCIS (Netherlands)

Scholtz, G.

2014-01-01

Compared with the elongate bodies of shrimps or lobsters, crabs are characterised by a compact body organisation with a depressed, short carapace and a ventrally folded pleon. The evolutionary transformation from a lobster-like crustacean towards a crab is called ‘carcinization’ and has been

CRAB3: Establishing a new generation of services for distributed analysis at CMS

International Nuclear Information System (INIS)

Cinquilli, M; Spiga, D; Konstantinov, P; Mascheroni, M; Grandi, C; Hernàndez, J M; Riahi, H; Vaandering, E

2012-01-01

In CMS Computing the highest priorities for analysis tools are the improvement of the end users’ ability to produce and publish reliable samples and analysis results as well as a transition to a sustainable development and operations model. To achieve these goals CMS decided to incorporate analysis processing into the same framework as data and simulation processing. This strategy foresees that all workload tools (TierO, Tier1, production, analysis) share a common core with long term maintainability as well as the standardization of the operator interfaces. The re-engineered analysis workload manager, called CRAB3, makes use of newer technologies, such as RESTFul based web services and NoSQL Databases, aiming to increase the scalability and reliability of the system. As opposed to CRAB2, in CRAB3 all work is centrally injected and managed in a global queue. A pool of agents, which can be geographically distributed, consumes work from the central services serving the user tasks. The new architecture of CRAB substantially changes the deployment model and operations activities. In this paper we present the implementation of CRAB3, emphasizing how the new architecture improves the workflow automation and simplifies maintainability. In particular, we will highlight the impact of the new design on daily operations.

CRAB3: Establishing a new generation of services for distributed analysis at CMS

Science.gov (United States)

Cinquilli, M.; Spiga, D.; Grandi, C.; Hernàndez, J. M.; Konstantinov, P.; Mascheroni, M.; Riahi, H.; Vaandering, E.

2012-12-01

In CMS Computing the highest priorities for analysis tools are the improvement of the end users’ ability to produce and publish reliable samples and analysis results as well as a transition to a sustainable development and operations model. To achieve these goals CMS decided to incorporate analysis processing into the same framework as data and simulation processing. This strategy foresees that all workload tools (TierO, Tier1, production, analysis) share a common core with long term maintainability as well as the standardization of the operator interfaces. The re-engineered analysis workload manager, called CRAB3, makes use of newer technologies, such as RESTFul based web services and NoSQL Databases, aiming to increase the scalability and reliability of the system. As opposed to CRAB2, in CRAB3 all work is centrally injected and managed in a global queue. A pool of agents, which can be geographically distributed, consumes work from the central services serving the user tasks. The new architecture of CRAB substantially changes the deployment model and operations activities. In this paper we present the implementation of CRAB3, emphasizing how the new architecture improves the workflow automation and simplifies maintainability. In particular, we will highlight the impact of the new design on daily operations.

CRAB3: Establishing a new generation of services for distributed analysis at CMS

Energy Technology Data Exchange (ETDEWEB)

Cinquilli, M. [CERN; Spiga, D. [CERN; Grandi, C. [INFN, Bologna; Hernandez, J. M. [Madrid, CIEMAT; Konstantinov, P. [CERN; Mascheroni, M. [CERN; Riahi, H. [INFN, Perugia; Vaandering, E. [Fermilab

2012-01-01

In CMS Computing the highest priorities for analysis tools are the improvement of the end users ability to produce and publish reliable samples and analysis results as well as a transition to a sustainable development and operations model. To achieve these goals CMS decided to incorporate analysis processing into the same framework as data and simulation processing. This strategy foresees that all workload tools (TierO, Tier1, production, analysis) share a common core with long term maintainability as well as the standardization of the operator interfaces. The re-engineered analysis workload manager, called CRAB3, makes use of newer technologies, such as RESTFul based web services and NoSQL Databases, aiming to increase the scalability and reliability of the system. As opposed to CRAB2, in CRAB3 all work is centrally injected and managed in a global queue. A pool of agents, which can be geographically distributed, consumes work from the central services serving the user tasks. The new architecture of CRAB substantially changes the deployment model and operations activities. In this paper we present the implementation of CRAB3, emphasizing how the new architecture improves the workflow automation and simplifies maintainability. In particular, we will highlight the impact of the new design on daily operations.

Toxicity of invert drilling muds composted with wood/bark chips

Energy Technology Data Exchange (ETDEWEB)

Bessie, K. [EBA Engineering Consultants Ltd., Calgary, AB (Canada)

2006-07-01

Since the early to mid 1990s, many companies have composted invert (diesel) drilling muds with wood chips/bark chips in the green (forestry) zone as a method of drilling mud treatment. This presentation addressed the toxicity of invert drilling muds composted with wood/bark chips and provided some background on composted invert drilling mud (CIDM). EBA Engineering monitored 22 third-party sites in 2002, some of which were biopiles, and others land treatment areas (LTAs). Active treatment started between 1995 and 1999 and some LTAs were seeded with varying degrees of success. Composted materials had hydrocarbon odour and staining and were very moist. Materials exceeded Alberta Environment guidelines for petroleum hydrocarbons (PHCs) and sometimes barium. Most sites were within areas that had forestry production/wildlife as end land use. Receptors included plants, soil invertebrates by soil contact, and wildlife by ingestion. Stakeholder meetings were held for their input and an ecotoxicity study was developed. Material tested, tests and species used as well as results of the ecotoxicity study were presented. A comparison of results to other EBA composting studies was also given. It was concluded that CIDM affects the reproduction of earthworms and springtails, and plant growth; wood/barks chips themselves can be ecotoxic; and, other compost studies with finely ground sawdust and no bark chips had less ecotoxicity. tabs., figs.

Removal of fluoride ions from aqueous solution by waste mud

International Nuclear Information System (INIS)

Kemer, Baris; Ozdes, Duygu; Gundogdu, Ali; Bulut, Volkan N.; Duran, Celal; Soylak, Mustafa

2009-01-01

The present study was carried out to assess the ability of original waste mud (o-WM) and different types of activated waste mud which are acid-activated (a-WM) and precipitated waste mud (p-WM), in order to remove excess of fluoride from aqueous solution by using batch technique. The p-WM exhibited greater performance than the others. Adsorption studies were conducted as a function of pH, contact time, initial fluoride concentration, adsorbent concentration, temperature, etc. Studies were also performed to understand the effect of some co-existing ions present in aqueous solutions. Adsorption process was found to be almost independent of pH for all types of waste mud. Among the kinetic models tested for p-WM, pseudo-second-order model fitted the kinetic data well with a perfect correlation coefficient value of 1.00. It was found that the adequate time for the adsorption equilibrium of fluoride was only 1 h. Thermodynamic parameters including the Gibbs free energy (ΔG o ), enthalpy (ΔH o ), and entropy (ΔS o ) revealed that adsorption of fluoride ions on the p-WM was feasible, spontaneous and endothermic in the temperature range of 0-40 deg. C. Experimental data showed a good fit with the Langmuir and Freundlich adsorption isotherm models. Results of this study demonstrated the effectiveness and feasibility of WM for removal of fluoride ions from aqueous solution.

A crab swarm at an ecological hotspot: patchiness and population density from AUV observations at a coastal, tropical seamount

Directory of Open Access Journals (Sweden)

Jesús Pineda

2016-04-01

Full Text Available A research cruise to Hannibal Bank, a seamount and an ecological hotspot in the coastal eastern tropical Pacific Ocean off Panama, explored the zonation, biodiversity, and the ecological processes that contribute to the seamount’s elevated biomass. Here we describe the spatial structure of a benthic anomuran red crab population, using submarine video and autonomous underwater vehicle (AUV photographs. High density aggregations and a swarm of red crabs were associated with a dense turbid layer 4–10 m above the bottom. The high density aggregations were constrained to 355–385 m water depth over the Northwest flank of the seamount, although the crabs also occurred at lower densities in shallower waters (∼280 m and in another location of the seamount. The crab aggregations occurred in hypoxic water, with oxygen levels of 0.04 ml/l. Barcoding of Hannibal red crabs, and pelagic red crabs sampled in a mass stranding event in 2015 at a beach in San Diego, California, USA, revealed that the Panamanian and the Californian crabs are likely the same species, Pleuroncodes planipes, and these findings represent an extension of the southern endrange of this species. Measurements along a 1.6 km transect revealed three high density aggregations, with the highest density up to 78 crabs/m2, and that the crabs were patchily distributed. Crab density peaked in the middle of the patch, a density structure similar to that of swarming insects.

Dominance and population structure of freshwater crabs ...

African Journals Online (AJOL)

1997-02-06

Feb 6, 1997 ... Intraspecific aggression, predation and refuge availability are probable strong selection pressures in determining ... Hluhluwe Game Reserve, P.O. Box 25, 3935 .... video recorder in order not to disturb the crabs during obser-.

OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE - A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING

Energy Technology Data Exchange (ETDEWEB)

Alan Black; Arnis Judzis

2003-01-01

Progress during current reporting year 2002 by quarter--Progress during Q1 2002: (1) In accordance to Task 7.0 (D. No.2 Technical Publications) TerraTek, NETL, and the Industry Contributors successfully presented a paper detailing Phase 1 testing results at the February 2002 IADC/SPE Drilling Conference, a prestigious venue for presenting DOE and private sector drilling technology advances. The full reference is as follows: IADC/SPE 74540 ''World's First Benchmarking of Drilling Mud Hammer Performance at Depth Conditions'' authored by Gordon A. Tibbitts, TerraTek; Roy C. Long, US Department of Energy, Brian E. Miller, BP America, Inc.; Arnis Judzis, TerraTek; and Alan D. Black, TerraTek. Gordon Tibbitts, TerraTek, will presented the well-attended paper in February of 2002. The full text of the Mud Hammer paper was included in the last quarterly report. (2) The Phase 2 project planning meeting (Task 6) was held at ExxonMobil's Houston Greenspoint offices on February 22, 2002. In attendance were representatives from TerraTek, DOE, BP, ExxonMobil, PDVSA, Novatek, and SDS Digger Tools. (3) PDVSA has joined the advisory board to this DOE mud hammer project. PDVSA's commitment of cash and in-kind contributions were reported during the last quarter. (4) Strong Industry support remains for the DOE project. Both Andergauge and Smith Tools have expressed an interest in participating in the ''optimization'' phase of the program. The potential for increased testing with additional Industry cash support was discussed at the planning meeting in February 2002. Progress during Q2 2002: (1) Presentation material was provided to the DOE/NETL project manager (Dr. John Rogers) for the DOE exhibit at the 2002 Offshore Technology Conference. (2) Two meeting at Smith International and one at Andergauge in Houston were held to investigate their interest in joining the Mud Hammer Performance study. (3) SDS Digger Tools (Task 3

Modelling the ArH+ emission from the Crab nebula

Science.gov (United States)

Priestley, F. D.; Barlow, M. J.; Viti, S.

2017-12-01

We have performed combined photoionization and photodissociation region (PDR) modelling of a Crab nebula filament subjected to the synchrotron radiation from the central pulsar wind nebula, and to a high flux of charged particles; a greatly enhanced cosmic-ray ionization rate over the standard interstellar value, ζ0, is required to account for the lack of detected [C I] emission in published Herschel SPIRE FTS observations of the Crab nebula. The observed line surface brightness ratios of the OH+ and ArH+ transitions seen in the SPIRE FTS frequency range can only be explained with both a high cosmic-ray ionization rate and a reduced ArH+ dissociative recombination rate compared to that used by previous authors, although consistent with experimental upper limits. We find that the ArH+/OH+ line strengths and the observed H2 vibration-rotation emission can be reproduced by model filaments with nH = 2 × 104 cm-3, ζ = 107ζ0 and visual extinctions within the range found for dusty globules in the Crab nebula, although far-infrared emission from [O I] and [C II] is higher than the observational constraints. Models with nH = 1900 cm-3 underpredict the H2 surface brightness, but agree with the ArH+ and OH+ surface brightnesses and predict [O I] and [C II] line ratios consistent with observations. These models predict HeH+ rotational emission above detection thresholds, but consideration of the formation time-scale suggests that the abundance of this molecule in the Crab nebula should be lower than the equilibrium values obtained in our analysis.

Absolute quantification method and validation of airborne snow crab allergen tropomyosin using tandem mass spectrometry

International Nuclear Information System (INIS)

Rahman, Anas M. Abdel; Lopata, Andreas L.; Randell, Edward W.; Helleur, Robert J.

2010-01-01

Measuring the levels of the major airborne allergens of snow crab in the workplace is very important in studying the prevalence of crab asthma in workers. Previously, snow crab tropomyosin (SCTM) was identified as the major aeroallergen in crab plants and a unique signature peptide was identified for this protein. The present study advances our knowledge on aeroallergens by developing a method of quantification of airborne SCTM by using isotope dilution mass spectrometry. Liquid chromatography tandem mass spectrometry was developed for separation and analysis of the signature peptides. The tryptic digestion conditions were optimized to accomplish complete digestion. The validity of the method was studied using international conference on harmonization protocol, Where 2-9% for CV (precision) and 101-110% for accuracy, at three different levels of quality control. Recovery of the spiked protein from PTFE and TopTip filters was measured to be 99% and 96%, respectively. To further demonstrate the applicability and the validity of the method for real samples, 45 kg of whole snow crab were processed in an enclosed (simulated) crab processing line and air samples were collected. The levels of SCTM ranged between 0.36-3.92 μg m -3 and 1.70-2.31 μg m -3 for butchering and cooking stations, respectively.

Absolute quantification method and validation of airborne snow crab allergen tropomyosin using tandem mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Rahman, Anas M. Abdel, E-mail: anasar@mun.ca [Department of Chemistry, Memorial University of Newfoundland, St. John' s, Newfoundland A1B 3X7 (Canada); Lopata, Andreas L. [School of Applied Science, Marine Biomedical Sciences and Health Research Group, RMIT University, Bundoora, 3083 Victoria (Australia); Randell, Edward W. [Department of Laboratory Medicine, Memorial University of Newfoundland, Eastern Health, St. John' s, Newfoundland and Labrador A1B 3V6 (Canada); Helleur, Robert J. [Department of Chemistry, Memorial University of Newfoundland, St. John' s, Newfoundland A1B 3X7 (Canada)

2010-11-29

Measuring the levels of the major airborne allergens of snow crab in the workplace is very important in studying the prevalence of crab asthma in workers. Previously, snow crab tropomyosin (SCTM) was identified as the major aeroallergen in crab plants and a unique signature peptide was identified for this protein. The present study advances our knowledge on aeroallergens by developing a method of quantification of airborne SCTM by using isotope dilution mass spectrometry. Liquid chromatography tandem mass spectrometry was developed for separation and analysis of the signature peptides. The tryptic digestion conditions were optimized to accomplish complete digestion. The validity of the method was studied using international conference on harmonization protocol, Where 2-9% for CV (precision) and 101-110% for accuracy, at three different levels of quality control. Recovery of the spiked protein from PTFE and TopTip filters was measured to be 99% and 96%, respectively. To further demonstrate the applicability and the validity of the method for real samples, 45 kg of whole snow crab were processed in an enclosed (simulated) crab processing line and air samples were collected. The levels of SCTM ranged between 0.36-3.92 {mu}g m{sup -3} and 1.70-2.31 {mu}g m{sup -3} for butchering and cooking stations, respectively.

Mercury burdens in Chinese mitten crabs (Eriocheir sinensis) in three tributaries of southern San Francisco Bay, California, USA

Energy Technology Data Exchange (ETDEWEB)

Hui, Clifford A. [US Geological Survey, 7801 Folsom Blvd, Suite 101, Sacramento, CA 95826 (United States)]. E-mail: bioinvestigations@sbcglobal.net; Rudnick, Deborah [Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720 (United States); Williams, Erin [US Fish and Wildlife Service, 4001 N. Wilson Way, Stockton, CA 95205 (United States)

2005-02-01

Chinese mitten crabs (Eriocheir sinensis), endemic to Asia, were first reported in the San Francisco Bay in 1992. They are now established in nearly all San Francisco Bay tributaries. These crabs accumulate more metals, such as mercury, than crustaceans living in the water column. Because their predators include fish, birds, mammals and humans, their mercury burdens have an exceptional potential to impact the ecosystem and public health. We sought to elucidate the potential threat of mitten crab mercury burdens in three adjacent streams in southern San Francisco Bay, one of which is known to be contaminated with mercury. Mitten crabs had hepatopancreas concentrations of total mercury and methylmercury that did not differ among streams. The maximum burden we measured was below the action level of 1 ppm recommended by the USEPA. Hepatopancreas concentrations of methylmercury declined with increasing crab size, suggesting a mechanism for mercury excretion and that predators might reduce mercury exposure if they select larger crabs. Because mercury may be heterogeneously distributed among tissues, estimation of the impacts of crab mercury burdens on the environment requires more data on the feeding preferences of predators. - Hepatopancreas concentrations of mercury decline with crab size, which may have important consequences for bio-magnification in food webs.

Mercury burdens in Chinese mitten crabs (Eriocheir sinensis) in three tributaries of southern San Francisco Bay, California, USA

International Nuclear Information System (INIS)

Hui, Clifford A.; Rudnick, Deborah; Williams, Erin

2005-01-01

Chinese mitten crabs (Eriocheir sinensis), endemic to Asia, were first reported in the San Francisco Bay in 1992. They are now established in nearly all San Francisco Bay tributaries. These crabs accumulate more metals, such as mercury, than crustaceans living in the water column. Because their predators include fish, birds, mammals and humans, their mercury burdens have an exceptional potential to impact the ecosystem and public health. We sought to elucidate the potential threat of mitten crab mercury burdens in three adjacent streams in southern San Francisco Bay, one of which is known to be contaminated with mercury. Mitten crabs had hepatopancreas concentrations of total mercury and methylmercury that did not differ among streams. The maximum burden we measured was below the action level of 1 ppm recommended by the USEPA. Hepatopancreas concentrations of methylmercury declined with increasing crab size, suggesting a mechanism for mercury excretion and that predators might reduce mercury exposure if they select larger crabs. Because mercury may be heterogeneously distributed among tissues, estimation of the impacts of crab mercury burdens on the environment requires more data on the feeding preferences of predators. - Hepatopancreas concentrations of mercury decline with crab size, which may have important consequences for bio-magnification in food webs

75 FR 49420 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Science.gov (United States)

2010-08-13

.... 100513223-0289-02] RIN 0648-AY88 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In- season Adjustment AGENCY: National Marine...-sea (DAS) allocation for the Atlantic deep- sea red crab fishery that were implemented in May 2010...

Evaluation of the hurricanes Gustav and Ike impact on healing mud from San Diego River using nuclear and geochemical techniques

International Nuclear Information System (INIS)

Diaz Rizo, Oscar; Gelen Rudnikas, Alina Katia; Rodriguez, D'Alessandro; Arado Lopez, Juana O.; Dominguez Rodriguez, Roberto; Gonzalez Hernandez, Patricia; Melian Rodriguez, Clara M.; Suarez Munnoz, Margaret; Fagundo Castillo, Juan R.; Blanco Padilla, Dagoberto

2011-01-01

Effects induced by the hurricanes Gustav and Ike on San Diego River mud characteristics have been studied. X-ray fluorescence analysis, gamma spectrometry and measurement of some physico-chemical characteristics in mud samples, collected before and after hurricane impacts, shows that hurricanes induced changes in mud major composition and in some other mud characteristics. The average sedimentation rate determined by gamma spectrometry in San Diego River outlet permitted to estimate that the original mud characteristics will be recovered never before than 5-7 years. Further studies of the influence of mud characteristics changes due the hurricanes impact in mud therapeutic properties are recommended.(author)

Heterogeneous Catalysts for VOC Oxidation from Red Mud and Bagasse Ash Carbon

Science.gov (United States)

Pande, Gaurav

A range of VOC oxidation catalysts have been prepared in this study from agricultural and industrial waste as the starting point. The aim is to prepare catalysts with non-noble metal oxides as the active catalytic component (iron in red mud). The same active component was also supported on activated carbon obtained from unburned carbon in bagasse ash. Red mud which is an aluminum industry waste and rich in different phases of iron as oxide and hydroxide is used as the source for the catalytically active species. It is our aim to enhance the catalytic performance of red mud which though high in iron concentration has a low surface area and may not have the properties of an ideal catalyst by itself. In one of the attempts to enhance the catalytic performance, we have tried to leach red mud for which we have explored a range of leaching acids for effecting the leaching most efficiently and then precipitated the iron from the leachate as its hydroxide by precipitating with alkali solution followed by drying and calcination to give high surface area metal oxide material. Extensive surface characterization and VOC oxidation catalytic testing were performed for these solids. In a step to further enhance the catalytic activity towards oxidation, copper was introduced by taking another industrial waste from the copper tubing industry viz. the pickling acid. Copper has a more favourable redox potential making it catalytically more effective than iron. To make the mixed metal oxide, red mud leachate was mixed with the pickling acid in a pre-decided ratio before precipitating with alkali solution followed by drying and calcination as was done with the red mud leachate. The results from these experiments are encouraging. The temperature programmed reduction (TPR) of the solids show that the precipitate of red mud leachates show hydrogen uptake peak at a lower temperature than for just the calcined red mud. This could be due to the greatly enhanced surface area of the prepared

Selection of parameters for mud pumps used for HDD Systems

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Jan Ziaja

2006-10-01

Full Text Available Design solutions of rigs used for HDD are presented in the paper. HDD devices are classified on the basis of presented criteria, and then a division of rigs was proposed. The principles of determining technological parameters of piston mud pumps for HDD are presented. The principles of determining volume flow rate for an arbitrary rheological model of drilling mud are discussed. The dependences enabling a calculation of resistance of drilling fluid flow in a circulation system are also presented.

Sulfur Fixation by Chemically Modified Red Mud Samples Containing Inorganic Additives: A Parametric Study

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Yang Liu

2016-01-01

Full Text Available Sulfur retention ability of Bayer red mud from alumina plant was investigated. Bayer red mud modified by fusel salt and waste mother liquor of sodium ferrocyanide as the main sulfur fixation agent and the calcium based natural mineral materials as servicing additives; the experimental results showed the following: (1 Through 10 wt% waste mother liquor of sodium ferrocyanide modifying Bayer red mud, sulfur fixation rate can increase by 13 wt%. (2 Magnesium oxide can obviously improve the sulfur fixation performance of Bayer red mud and up to a maximum sulfur fixation rate of 47 wt% at adding 1 wt% magnesium oxide. (3 Dolomite enhanced the sulfur fixation performances with the sulfur fixation rate of 68 wt% in optimized condition. (4 Vermiculite dust reduced sulfur dioxide during the fixed-sulfur process of modified Bayer red mud, and the desulphurization ration could reach up to a maximum 76 wt% at 950°C. (5 An advanced three-component sulfur fixation agent was investigated, in which the optimized mass ratio of modified Bayer red mud, dolomite, and vermiculite dust was 70 : 28 : 2 in order, and its sulfur fixation efficiency has reached to a maximum 87 wt% under its 20 wt% dosage in the coal.

A comparative study of modern carbonate mud in reefs and carbonate platforms: Mostly biogenic, some precipitated

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Gischler, Eberhard; Dietrich, Sarah; Harris, Daniel; Webster, Jody M.; Ginsburg, Robert N.

2013-06-01

Carbonate mud from reefs and carbonate platforms in six locations of the Atlantic, Indian, and Pacific Oceans (Belize, Bahamas, Florida, the Maldives, French Polynesia, Great Barrier Reef) was systematically and quantitatively analyzed with regard to texture, composition, mineralogy, and geochemistry. Mud composition shows considerable variability, however, the data supports the contention that these muds are largely derived from the breakdown of skeletal grains and codiacean algae. Only mud from the Bahamas and northern Belize, areas which are characterized by common whitings, is interpreted to be mainly inorganically precipitated. Three grain-size fractions (63-20 μm, 20-4 μm, aragonite needles, nanograins, and coccoliths. Coccoliths are common in deeper lagoonal settings of the open ocean settings (Maldives, French Polynesia). The geochemistry of the aragonite contents and strontium concentrations, suggesting physico-chemical precipitation. The northern Belize and Great Barrier Reef samples show the highest magnesium calcite values and, accordingly, produced the lowest aragonite and strontium measurements. The high-magnesium calcite portion of the northern Belize mud is either precipitated or due to abundant micritized skeletal grains (e.g., foraminifera): more studies are needed to verify the origin. In the case of the Great Barrier Reef sample, coralline algae appear to be the source of abundant high-magnesium calcite. This study emphasizes that from a global perspective, modern muds in reefs and carbonate platforms exhibit different compositions but are in many cases biologically derived. Even though the composition of modern carbonate muds varies among the six locations investigated, they may serve as analogs for the formation of muds in Cenozoic and Mesozoic reefs and carbonate platforms. Limitations of the interpretation of carbonate-mud origin include the difficulty of identifying, quantifying, and analyzing small grains, the ease with which small

AFSC/REFM: BSAI Crab Economic Data Report

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Economic data collected for years 1998, 2001, 2004, and 2005 and onward for the BSAI Crab Economic Data Report (EDR). Reporting is required of any owner or...

Characteristics of laser textured silicon surface and effect of mud adhesion on hydrophobicity

Energy Technology Data Exchange (ETDEWEB)

Yilbas, B.S., E-mail: bsyilbas@kfupm.edu.sa [ME Department, King Fahd University of Petroleum & Minerals, Kfupm box 1913, Dhahran 31261 (Saudi Arabia); Ali, H. [ME Department, King Fahd University of Petroleum & Minerals, Kfupm box 1913, Dhahran 31261 (Saudi Arabia); Khaled, M. [CHEM Department, King Fahd University of Petroleum & Minerals, Dhahran (Saudi Arabia); Al-Aqeeli, N.; Abu-Dheir, N. [ME Department, King Fahd University of Petroleum & Minerals, Kfupm box 1913, Dhahran 31261 (Saudi Arabia); Varanasi, K.K. [Mechanical Engineering, Massachusetts Institute of Technology, Boston, MA (United States)

2015-10-01

Highlights: • Laser treatment increases surface microhardness and slightly lowers surface fracture toughness. • Residual stress formed is compressive and self-annealing effect of laser tracks lowers residual stress. • Nitride species lowers surface energy and adhesion work required to remove dust. • Mud residues do not have notable effect on fracture toughness and microhardness of treated surface. • Mud residues lower surface hydrophobicity. - Abstract: Laser gas assisted texturing of silicon wafer surface is carried out. Morphological and metallurgical changes in the treated layer are examined using the analytical tools. Microhardness and fracture toughness of the laser treated surface are measured using the indentation technique while residual stress formed is determined from the X-ray diffraction data. The hydrophobicity of the textured surfaces are assessed incorporating the contact angle data and compared with those of as received workpiece surfaces. Environmental dust accumulation and mud formation, due to air humidity, at the laser treated and as received workpiece surfaces are simulated and the effect of the mud residues on the properties of the laser treated surface are studied. The adhesion work due to the presence of the mud on the laser treated surface is also measured. It is found that laser textured surface composes of micro/nano poles and fibers, which in turn improves the surface hydrophobicity significantly. In addition, formation of nitride species contributes to microhardness increase and enhancement of surface hydrophobicity due to their low surface energy. The mud residues do not influence the fracture toughness and microhardness of the laser textured surface; however, they reduced the surface hydrophobicity significantly.

Cellular immune responses and phagocytic activity of fishes exposed to pollution of volcano mud.

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Risjani, Yenny; Yunianta; Couteau, Jerome; Minier, Christophe

2014-05-01

Since May 29, 2006, a mud volcano in the Brantas Delta of the Sidoarjo district has emitted mud that has inundated nearby villages. Pollution in this area has been implicated in detrimental effects on fish health. In fishes, leukocyte and phagocytic cells play a vital role in body defenses. We report for the first time the effect of "LUSI" volcano mud on the immune systems of fish in the Brantas Delta. The aim of this study was to find biomarkers to allow the evaluation of the effects of volcanic mud and anthropogenic pollution on fish health in the Brantas Delta. The study took places at the Brantas Delta, which was polluted by volcano mud, and at reference sites in Karangkates and Pasuruan. Leukocyte numbers were determined using a Neubauer hemocytometer and a light microscope. Differential leukocyte counts were determined using blood smears stained with May Grunwald-Giemsa, providing neutrophil, lymphocyte and monocyte counts. Macrophages were taken from fish kidney, and their phagocytic activity was measured. In vitro analyses revealed that leukocyte and differential leukocyte counts (DLC) were higher in Channa striata and Chanos chanos caught from the polluted area. Macrophage numbers were higher in Oreochromis mossambicus than in the other species, indicating that this species is more sensitive to pollution. In areas close to volcanic mud eruption, all specimens had lower phagocytic activity. Our results show that immune cells were changed and phagocytic activity was reduced in the polluted area indicating cytotoxicity and alteration of the innate immune system in fishes exposed to LUSI volcano mud and anthropogenic pollution. Copyright © 2014 Elsevier Ltd. All rights reserved.

75 FR 35435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Science.gov (United States)

2010-06-22

.... 100513223-0254-01] RIN 0648-AY88 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In- season Adjustment AGENCY: National Marine... deep-sea red crab fishery, including a target total allowable catch (TAC) and a fleet-wide days-at-sea...

Elemental compositions of crab and snail shells from the Kueishantao hydrothermal field in the southwestern Okinawa Trough

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Zeng, Zhigang; Ma, Yao; Wang, Xiaoyuan; Chen, Chen-Tung Arthur; Yin, Xuebo; Zhang, Suping; Zhang, Junlong; Jiang, Wei

2018-04-01

To reveal differences in the behavior of benthic vent animals, and the sources and sinks of biogeochemical and fluid circulations, it is necessary to constrain the chemical characteristics of benthic animals from seafloor hydrothermal fields. We measured the abundances of 27 elements in shells of the crab Xenograpsus testudinatus and the snail Anachis sp., collected from the Kueishantao hydrothermal field (KHF) in the southwestern Okinawa Trough, with the aim of improving our understanding of the compositional variations between individual vent organisms, and the sources of the rare earth elements (REEs) in their shells. The Mn, Hg, and K concentrations in the male X. testudinatus shells are found to be higher than those in female crab shells, whereas the reverse is true for the accumulation of B, implying that the accumulation of K, Mn, Hg, and B in the crab shells is influenced by sex. This is inferred to be a result of the asynchronous molting of the male and female crab shells. Snail shells are found to have higher Ca, Al, Fe, Ni, and Co concentrations than crab shells. This may be attributed to different metal accumulation times. The majority of the light rare earth element (LREE) distribution patterns in the crab and snail shells are similar to those of Kueishantao vent fluids, with the crab and snail shells also exhibiting LREE enrichment, implying that the LREEs contained in crab and snail shells in the KHF are derived from vent fluids.

Flood Tide Transport of Blue Crab Postlarvae: Limitations in a Lagoonal Estuary

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Cudaback, C.; Eggleston, D.

2005-05-01

Blue crabs, an important commercial species, spend much of their life in estuaries along the east coast. The larvae spawn at or near the ocean, but the juveniles mature in the lower salinity waters of the estuary. It is generally believed that blue crab postlarvae migrate into near surface waters on flood, possibly cued by increasing salinity, and return to the bottom on ebb. Over several tidal cycles, the postlarvae travel a significant distance up-estuary. This model applies quite well to Chesapeake Bay, which has a strong along-estuary salinity gradient and large tides, but may not apply as well to Pamlico Sound, where circulation and salinity are more wind-driven than tidal. A recently completed study (N. Reyns, PhD), indicates that postlarval blue crabs use flood tides and wind-driven currents to cross Pamlico Sound. This study was based on observations with good spatial coverage, but limited vertical and temporal resolution. We have recently completed a complementary study, sampling crab larvae around the clock at four depths at a single location. Preliminary results from the new study suggest that the crab postlarvae do swim all the way to the surface, on flood only, and that flood currents are strongest slightly below the surface. These observations suggest the utility of flood tide transport in this system. However, near bottom salinity does not seem to be driven by tides; at this point it is unclear what cue might trigger the vertical migration of the postlarvae.

Environmental control of drilling mud discharge through dewatering in cold weather climates

International Nuclear Information System (INIS)

Wojtanowicz, A.K.

1991-01-01

The paper presents results of an experimental study into the effect of drilling mud temperature upon the dewatering performance. Three temperature ranges were considered: from flowline temperature to room temperature, from room temperature to freezing point, and the freeze (4 degrees F)/thaw (54 degrees F) cycle. The tested drilling fluids included unweighted and weighted fresh water muds and a weighted salt water mud. a sealed laboratory batch reactor was used in the experiments to prevent rapid vaporization of separated water at temperatures above 140 degrees F. Also, ice or ice-salt baths were utilized for deep freezing. The dewaterability (net water removal) was measured with a bench-top plate press under constant expression pressure 30 psi

Evolution and phylogeny of the mud shrimps (Crustacea: Decapoda) revealed from complete mitochondrial genomes.

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Lin, Feng-Jiau; Liu, Yuan; Sha, Zhongli; Tsang, Ling Ming; Chu, Ka Hou; Chan, Tin-Yam; Liu, Ruiyu; Cui, Zhaoxia

2012-11-16

The evolutionary history and relationships of the mud shrimps (Crustacea: Decapoda: Gebiidea and Axiidea) are contentious, with previous attempts revealing mixed results. The mud shrimps were once classified in the infraorder Thalassinidea. Recent molecular phylogenetic analyses, however, suggest separation of the group into two individual infraorders, Gebiidea and Axiidea. Mitochondrial (mt) genome sequence and structure can be especially powerful in resolving higher systematic relationships that may offer new insights into the phylogeny of the mud shrimps and the other decapod infraorders, and test the hypothesis of dividing the mud shrimps into two infraorders. We present the complete mitochondrial genome sequences of five mud shrimps, Austinogebia edulis, Upogebia major, Thalassina kelanang (Gebiidea), Nihonotrypaea thermophilus and Neaxius glyptocercus (Axiidea). All five genomes encode a standard set of 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a putative control region. Except for T. kelanang, mud shrimp mitochondrial genomes exhibited rearrangements and novel patterns compared to the pancrustacean ground pattern. Each of the two Gebiidea species (A. edulis and U. major) and two Axiidea species (N. glyptocercus and N. thermophiles) share unique gene order specific to their infraorders and analyses further suggest these two derived gene orders have evolved independently. Phylogenetic analyses based on the concatenated nucleotide and amino acid sequences of 13 protein-coding genes indicate the possible polyphyly of mud shrimps, supporting the division of the group into two infraorders. However, the infraordinal relationships among the Gebiidea and Axiidea, and other reptants are poorly resolved. The inclusion of mt genome from more taxa, in particular the reptant infraorders Polychelida and Glypheidea is required in further analysis. Phylogenetic analyses on the mt genome sequences and the distinct gene orders provide further

Production of Green Steel from Red Mud: A Novel Concept

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Bhoi, Bhagyadhar; Behera, Pravas Ranjan; Mishra, Chitta Ranjan

Red mud of Indian origin contains around 55% plus of Fe2O3 and is considered as a hazardous waste for the alumina industry. For production of one tone of alumina employing the Bayer's Process, around two tones of red mud is generated from three tones of Bauxite. Conventional process of steel making is not devoid of environmental pollution. In the present investigation, efforts have been made to produce steel from red mud by adopting reduction roasting, magnetic separation and hydrogen plasma smelting route. Magnetic fraction, containing enriched iron oxide and minimal content of alumina, is produced following the first two stages which is then subjected to hydrogen plasma smelting process for production of steel. This novel concept follows a green path way for production of steel free from pollution and is termed as green steel. Further, the only by-product that is produced in the process, is water, which is eco-friendly and recyclable.

Effects of Red-mud and Organic Fertilizer on Cadmium and Lead Absorption and Distribution in Rice

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FANG Ya-yu

2016-09-01

Full Text Available Effects of red mud and organic fertilizer on distribution of cadmium(Cd and lead (Pb in soil-rice system were studied in field by orthogonal test. Results showed that after red mud and organic fertilizer added including single and combined, the soil pH value increased 0.36~1.90 units, contents of Cd and Pb in rice rhizosphere soil decreased 2.73%~26.25% and 7.15%~34.26% respectively and contents of Cd and Pb in brown rice decreased 23.24%~55.90% and 11.76%~29.41% respectively. In all treatments, single red mud was best, followed by red mud and organic fertilizer combined, single organic fertilizer was worst. The content of Cd and Pb in different rice organs with addition of red mud and organic fertilizer decreased significantly, the contribution rate of Cd and Pb at different stages changed obviously, and influences of adding quantity and fertilizing method were also significant. Different treatments had different effects on contents of Cd and Pb in brown rice. Compared with CK, red mud (4 000 kg·hm-2 was the best for Cd, combination of red mud (4 000 kg·hm-2 and organic fertilizer (1 000 kg·hm-2was the best for Pb, the contents of which were 55.90% and 29.41% less than the control respectively. Although contents of Cd and Pb in brown rice decreased significantly after red mud and organic fertilizer added, contents of Cd and Pb in brown rice were still higher than national food safety standards (GB 2762-2012 because of high polluted degree of Cd (65 times than standard and Pb(7 times than standard in soil. All results showed it was ineffective to control heavy metal pollution in brown rice only by red mud and organic fertilizer addition in high polluted degree soils.

Maine belowground marsh destruction from the European green crab documented by computer-aided tomography

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Invasive European green crab (Carcinus maenus) populations have exploded with devastating losses to Maine’s intertidal resources including soft-shell clams, eelgrass beds, and salt marshes. This project quantified the green crab abundance in three different marsh locations ...

Epizoic and ectoparasitic protozoans from crab larvae