Structure-guided approach to site-specific fluorophore labeling of the lac repressor LacI.

Directory of Open Access Journals (Sweden)

Kalle Kipper

Full Text Available The lactose operon repressor protein LacI has long served as a paradigm of the bacterial transcription factors. However, the mechanisms whereby LacI rapidly locates its cognate binding site on the bacterial chromosome are still elusive. Single-molecule fluorescence imaging approaches are well suited for the study of these mechanisms but rely on a functionally compatible fluorescence labeling of LacI. Particularly attractive for protein fluorescence labeling are synthetic fluorophores due to their small size and favorable photophysical characteristics. Synthetic fluorophores are often conjugated to natively occurring cysteine residues using maleimide chemistry. For a site-specific and functionally compatible labeling with maleimide fluorophores, the target protein often needs to be redesigned to remove unwanted native cysteines and to introduce cysteines at locations better suited for fluorophore attachment. Biochemical screens can then be employed to probe for the functional activity of the redesigned protein both before and after dye labeling. Here, we report a mutagenesis-based redesign of LacI to enable a functionally compatible labeling with maleimide fluorophores. To provide an easily accessible labeling site in LacI, we introduced a single cysteine residue at position 28 in the DNA-binding headpiece of LacI and replaced two native cysteines with alanines where derivatization with bulky substituents is known to compromise the protein's activity. We find that the redesigned LacI retains a robust activity in vitro and in vivo, provided that the third native cysteine at position 281 is retained in LacI. In a total internal reflection microscopy assay, we observed individual Cy3-labeled LacI molecules bound to immobilized DNA harboring the cognate O1 operator sequence, indicating that the dye-labeled LacI is functionally active. We have thus been able to generate a functional fluorescently labeled LacI that can be used to unravel mechanistic

FUNGI ASSOCIATED WITH AFRICAN MUDFISH (Clarias gariepinus ...

African Journals Online (AJOL)

userpc

Clarias gariepinus (African mudfish) and 144 fish holding water samples were collected from ... Finding these fungi in the fish holding water might have occurred through the use ... This increased .... microbial profile of some fish ponds in the.

Characterization of cowpea genotype resistance to Callosobruchus maculatus

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Maria de Jesus Passos de Castro

2013-09-01

Full Text Available The objective of this work was to characterize the resistance of 50 cowpea (Vigna unguiculata genotypes to Callosobruchus maculatus. A completely randomized design with five replicates per treatment (genotype was used. No-choice tests were performed using the 50 cowpea genotypes to evaluate the preference for oviposition and the development of the weevil. The genotypes IT85 F-2687, MN05-841 B-49, MNC99-508-1, MNC99-510-8, TVu 1593, Canapuzinho-1-2, and Sanzi Sambili show non-preference-type resistance (oviposition and feeding. IT81 D-1045 Ereto and IT81 D-1045 Enramador exhibit antibiosis against C. maculatus and descend from resistant genitors, which grants them potential to be used in future crossings to obtain cowpea varieties with higher levels of resistance.

UVB-induced gene expression in the skin of Xiphophorus maculatus Jp 163 B☆

Science.gov (United States)

Yang, Kuan; Boswell, Mikki; Walter, Dylan J.; Downs, Kevin P.; Gaston-Pravia, Kimberly; Garcia, Tzintzuni; Shen, Yingjia; Mitchell, David L.; Walter, Ronald B.

2014-01-01

Xiphophorus fish and interspecies hybrids represent long-standing models to study the genetics underlying spontaneous and induced tumorigenesis. The recent release of the Xiphophorus maculatus genome sequence will allow global genetic regulation studies of genes involved in the inherited susceptibility to UVB-induced melanoma within select backcross hybrids. As a first step toward this goal, we report results of an RNA-Seq approach to identify genes and pathways showing modulated transcription within the skin of X. maculatus Jp 163 B upon UVB exposure. X. maculatus Jp 163 B were exposed to various doses of UVB followed by RNA-Seq analysis at each dose to investigate overall gene expression in each sample. A total of 357 genes with a minimum expression change of 4-fold (p-adj fish skin to UVB exposure. PMID:24556253

Bioactivity of Lantana camara L. essential oil against Callosobruchus maculatus (Fabricius Bioactividad de aceite esencial de Lantana camara L. contra Callosobruchus maculatus (Fabricius

Directory of Open Access Journals (Sweden)

Nooshin Zandi-Sohani

2012-12-01

Full Text Available Lantana camara L. is a widespread plant species mostly native to subtropical and tropical regions of the world. In this study, insecticidal and repellent activities of L. camara essential oil were evaluated against Callosobruchus maculatus (Fabricius (Col: Bruchidae. Analysis of chemical composition by gas chromatography/mass spectrometry (GC/MS showed high amounts of sesquiterpenes, mainly α-humelene (23.3% and cis-caryophyllene (16.2%. The results showed that the essential oil of L. camara has strong repellent activity against adults of C. maculatus at all tested concentrations. After 2 and 4 h, 97.4 and 100% repellency was seen at highest concentrations of 0.4 μL cm-2, respectively. Moreover, the oil was found to be toxic to adults when applied by fumigation. Responses varied with the gender of insect and exposure time. The LC50 values were 282.7 and 187.9 μL L-1 for females and males, respectively. An increase in the exposure time from 3 to 24 h caused increasing in mortality from 23.6 to 100% in males and from 14.1 to 97.1% in females, at highest concentration (1160 μL L-1. According to these results, L. camara essential oil may be useful as an alternative for bean protection against C. maculatus.Lantana camara L. es una especie vegetal nativa de las regiones subtropicales y tropicales del mundo. En este estudio se evaluaron las actividades insecticida y repelente del aceite esencial de L. camara contra Callosobruchus maculatus (Fabricius. El análisis de la composición volátil de este aceite esencial mediante cromatografía de gas/ espectrometría de masa (GC/MS demostró la presencia de elevadas cantidades de sesquiterpenos, principalmente α-humuleno (23.3% y ci's-cariofileno (16.2%. Los resultados obtenidos demostraron que el aceite esencial de L. camara tiene una elevada actividad repelente contra los adultos de C. maculatus a todas las concentraciones ensayadas. Después de 2 y 4 h la concentración de 0.4 μL cm-2 causó 97

Natural LacI from E. coli Yields Faster Response and Higher Level of Expression than the LVA-Tagged LacI

DEFF Research Database (Denmark)

Andreassen, Patrick Rosendahl; Fredberg, Sofie; Horan, Mattias

2014-01-01

The lac promoter is one of the most commonly used promoters for expression control of recombinant genes in E. coli. In the absence of galactosides, the lac promoter is repressed by its repressor protein LacI. Since the lac promoter is regulated by a repressor, overexpression of LacI is necessary...

the haematological response of clarias gariepinus to changes in ...

African Journals Online (AJOL)

The effect of different acclimation temperatures on physiological parameters of. Clarias gariepinus ... distribution and normal metabolism of fish, failure to adapt to ... collapse in osmoregulatory functions .... to changes in oxygen level, salinity or.

Hormonal and haematological responses of Clarias gariepinus ...

African Journals Online (AJOL)

This study assessed hormonal and haematological responses of Clarias gariepinus to ammonia toxicity. Laboratory study of haematological responses of adult C. gariepinus to sub-lethal level of ammonia (2.2 g/l) at different exposure hours (0, 6, 24, 48, 72, 96 h) were carried out. Blood samples of C. gariepinus were ...

Anaemia in the freshwater catfish Clarias albopunctatus (Teleostei ...

African Journals Online (AJOL)

Haematological changes were studied in freshwater catfish Clarias albopunctatus exposed for 20 days to 25%, 50% and 100% concentrations of brewery wastewater prepared by dilution using tap water. Haemoglobin, haematocrit and erythrocyte counts in fish exposed to wastewater were significantly lower than in a ...

lac operon induction in Escherichia coli: Systematic comparison of IPTG and TMG induction and influence of the transacetylase LacA.

Science.gov (United States)

Marbach, Anja; Bettenbrock, Katja

2012-01-01

Most commonly used expression systems in bacteria are based on the Escherichia coli lac promoter. Furthermore, lac operon elements are used today in systems and synthetic biology. In the majority of the cases the gratuitous inducers IPTG or TMG are used. Here we report a systematic comparison of lac promoter induction by TMG and IPTG which focuses on the aspects inducer uptake, population heterogeneity and a potential influence of the transacetylase, LacA. We provide induction curves in E. coli LJ110 and in isogenic lacY and lacA mutant strains and we show that both inducers are substrates of the lactose permease at low inducer concentrations but can also enter cells independently of lactose permease if present at higher concentrations. Using a gfp reporter strain we compared TMG and IPTG induction at single cell level and showed that bimodal induction with IPTG occurred at approximately ten-fold lower concentrations than with TMG. Furthermore, we observed that lac operon induction is influenced by the transacetylase, LacA. By comparing two Plac-gfp reporter strains with and without a lacA deletion we could show that in the lacA(+) strain the fluorescence level decreased after few hours while the fluorescence further increased in the lacA(-) strain. The results indicate that through the activity of LacA the IPTG concentration can be reduced below an inducing threshold concentration-an influence that should be considered if low inducer amounts are used. Copyright © 2011 Elsevier B.V. All rights reserved.

Technique de production intensive du poisson chat africain, Clarias gariepinus

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Ducarme, C.

2003-01-01

Full Text Available Intensive Production of African Catfish, Clarias gariepinus. The African catfish, Clarias gariepinus, is well appreciated in Africa and reaches high prices on the town markets (2 - 3 Euro/kg. Although it is raised since 1974 and its production is increasing in Europe, Asia and Latin America, the African production is on standby. The intensive production systems (biomass: 10 - 400 kg/m3, production: 1 - 4 kg/m3/j in recirculated systems recently developed in Europe (family farms: 200 - 250 t/year are profitable when the selling price on the farm reach 1,2 Euro/kg. This kind of model could be adapted by the African fish farmers to their local conditions and finally contributed to an important development of fish culture in Africa.

Growth response of juveniles of Clarias bidorsalis to imported ...

African Journals Online (AJOL)

USER

2010-08-02

Aug 2, 2010 ... Growth response of Clarias bidorsalis juveniles weighing between 5 - 10 g that were fed with extruded. (floating) imported ... and showed that daily food consumption and weight gain of fish that were ... mental period. The feed ...

Properties of BL Lac objects

International Nuclear Information System (INIS)

Wolfe, A.M.; Pittsburgh, University, Pittsburgh, Pa.)

1980-01-01

The properties of BL Lacertae objects are examined in light of their recently realized similarities to quasars and associations with galactic radiation. The criteria typically used to define BL Lac objects are analyzed, with attention given to radio spectra, optical continual, radio and optical variability, optical polarization and emission lines, and evidence that BL Lac objects and optically violent variables represent the most compact and strongly variable sources among the general class of quasars is discussed. Connections between BL Lac objects and the galaxies in which they have been observed to be embedded are discussed and it is pointed out that no low-luminosity quasars have been found to be associated with first-ranked giant ellipticals. Future observations which may clarify the properties and relationships of BL Lac objects are indicated

Stress in African catfish (clarias gariepinus) following overland transportation

NARCIS (Netherlands)

Manuel, R.; Boerrigter, J.; Roques, J.; Heul, van der J.W.; Bos, van den R.; Flik, G.; Vis, van de J.W.

2014-01-01

Of the many stressors in aquaculture, transportation of fish has remained poorly studied. The objective of this study was therefore to assess the effects of a (simulated) commercial transportation on stress physiology of market-size African catfish (Clarias gariepinus). Catfish weighing

(Clarias gariepinus

Directory of Open Access Journals (Sweden)

Lawrence Ezemonye

2010-01-01

Full Text Available Clarias gariepinus fingerlings exposed to lethal and sublethal concentrations of Gammalin 20 were investigated in a renewal static bioassay with particular reference to behaviour, survival, and histopathological changes. Early symptoms of gammalin 20 lethal poisoning were, respiratory distress, increased physical activity, convulsions, erratic swimming, loss of equilibrium, and increased breathing activity. Behavioural response was dose dependent and decreased with decreased concentration. The 96-hour lethal concentration (LC50 value was 30 ppb. Histopathological changes of the gill, liver, and intestinal tissues of fish treated with sublethal concentration of gammalin 20 for twelve weeks showed gill distortion and fusion of adjacent secondary lamella as a result of hyperplasia and excessive mucus accumulation. The liver showed swelling of hepatocytes with mild necrosis, pyknosis, and vacuolation, while the intestine showed yellow bodies of the lamina propria at the tip of the mucosal fold.

Plasma and organ biochemistry Clarias gariepinus exposed to ...

African Journals Online (AJOL)

The effect of toluene on enzymes; Aspatate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) in the plasma, organs (gills, kidney, liver) and muscle of Clarias gariepinus was assessed. The activity of AST in the gill was variable among the treated group and between the treated groups and ...

The Discovery of Low-Luminosity BL Lacs

Science.gov (United States)

Rector, Travis A.; Stocke, John T.

1995-12-01

Many of the properties of BL Lacs have become explicable in terms of the ``relativistic beaming'' hypothesis whereby BL Lacs are ``highly beamed'' FR-I radio galaxies (i.e. our line of sight to these objects is nearly along the jet axis). Further, radio-selected BL Lacs (RBLs) are believed to be seen nearly ``on-axis'' (the line-of-sight angle theta ~ 8deg ) while X-ray selected BL Lacs (XBLs) are seen at larger angles (theta ~ 30deg ; the X-ray emitting jet is believed to be less collimated). However, a major problem with this model was that a transition population between beamed BL Lacs and unbeamed FR-Is had not been detected. Low-luminosity BL Lacs may be such a transition population, and were predicted to exist by Browne and Marcha (1993). We present ROSAT HRI images, VLA radio maps and optical spectra which confirm the existence of low-luminosity BL Lacs, objects which were previously mis-identified in the EMSS catalog as clusters of galaxies. Thus our results strengthen the relativistic beaming hypothesis.

Alternation of cowpea genotypes affects the biology of Callosobruchus maculatus (fabr. (Coleoptera: Bruchidae

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Lima Marcileyne Pessôa Leite de

2004-01-01

Full Text Available Callosobruchus maculatus (Fabr. is an important pest in stored cowpea, Vigna unguiculata (L. Walp., with ample distribution in tropical and subtropical regions. The effect of alternation of cowpea genotypes, susceptible (S and resistant (R, on the biology of (C. maculatus was studied after four generations. A no-choice test was carried out in a completely randomized design, factorial scheme, with five treatments, four host combinations (RR, RS, SR and SS and five replications. Each replication consisted of 30 grains of each genotype infested by two insect couples. The number of eggs per female was not different within or between combinations, evidencing that the genotypes and their alternation did not affect C. maculatus fecundity. Egg viability, however, varied between genotypes and between combinations. In combination RR, the longest duration of the immature stage was verified for genotype IT89KD-245; in addition, all genotypes presented the smallest survival for the same stage, resulting in a higher mortality of the pest. The resistance index categorized combination RR as moderately resistant for genotypes IT89KD-245, BR14-Mulato and BR17-Gurguéia, and as susceptible (S only for IT89KD-260, demonstrating that these combinations were not very adequate for the development of C. maculatus, a fact that was confirmed by the better performance of the pest on the genotype from combination SS, and because of a reduction in its performance when it returned to resistant genotypes.

Fungi associated with post-harvest deterioration of dried Clarias ...

African Journals Online (AJOL)

Fungi associated with post-harvest deterioration of dried Clarias gariepinus vended in some ... Journal of Aquatic Sciences ... Results revealed that fish samples from okpokpo market contained highest number (10) of fungal isolates while samples from Afaha ... Key Words: Mycoflora, isolation, fungi, Fusarium, C. gariepinus ...

Study on Feeding Habit of Clariid Catfish ( Clarias Gariepinus ...

African Journals Online (AJOL)

A survey was conducted to investigate the feeding habit of catfish (Clarias gariepinus Burchell, 1822) in Otamiri River, South-Eastern Nigeria. Stomach items analyzed include mainly algae, fish scales, annelids, benthic invertebrates, and detritus confirmed the fish as omnivorous species. However, few stomach contents ...

Lac dayet Aoua (Maroc)

African Journals Online (AJOL)

Saad

F.S.T. Fès - Sais, Université Sidi Mohammed Abdallah Fès, B.P. 2202, Maroc. 2Laboratoire des ... d'étude en complément de la composition phytoplanctonique et des analyses de la physico-chimie des eaux à l'entrée, au ... L'analyse des paramètres physico-chimiques, au point central du lac, a montré que l'eau du lac.

Behavioural and biochemical responses of juvenile catfish ( Clarias ...

African Journals Online (AJOL)

The behavioural and serum liver enzyme responses of juvenile catfish (Clarias gariepinus) were evaluated for 72 hours. Thirty-six (36) healthy fishes with standard weight, 20 ± 1.52 g and standard length, 18.25 ± 0.50 cm were used for the experiment in non-renewable bioassay system. The test fish exhibited stressful ...

The damage caused by Callosobruchus maculatus on cowpea grains is dependent on the plant genotype.

Science.gov (United States)

Torres, Elida Barros; Nóbrega, Rafaela S A; Fernandes-Júnior, Paulo Ivan; Silva, Luciana Barboza; Dos Santos Carvalho, Gabriel; Marinho, Rita de Cassia Nunes; Pavan, Bruno E

2016-09-01

Beans from cowpea cultivars fertilized with mineral N or inoculated with various rhizobium strains may contain different nitrogen concentrations and nitrogen metabolite composition, which affects the beans' defense mechanisms against pests. In this study, the population growth of Callosobruchus maculatus reared on beans from four cowpea cultivars fertilized with different nitrogen sources was evaluated. The factors tested were beans from four cowpea cultivars and seven different nitrogen sources: mineral N fertilization, inoculation with five strains of symbiotic diazotrophic bacteria, and soil nitrogen (absolute control). BRS Tapaihum and BRS Acauã cultivars had lower cumulative emergence and instantaneous rate of population growth of the insects compared with other cultivars, indicating antixenosis resistance against C. maculatus. Inoculation of BRS Acauã cultivar with the diazotrophic bacteria strain BR 3299 resulted in higher mortality of C. maculatus. For BRS Tapaihum cultivar, inoculation with diazotrophic bacteria strains BR3267, BR 3262 and BR 3299, and nitrogen fertilization resulted in higher mortality among C. maculatus. BRS Tapaihum and BRS Acauã cultivars showed the lowest cumulative insect emergence and instantaneous rates of population growth, and the highest insect mortality, mainly when the grains were obtained from plants inoculated with rhizobial strains. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Global proteome changes in larvae of Callosobruchus maculatus Coleoptera:Chrysomelidae:Bruchinae) following ingestion of a cysteine proteinase inhibitor

DEFF Research Database (Denmark)

Nogueira, Fábio C S; Silva, Carlos P; Alexandre, Daniel

2012-01-01

The seed-feeding beetle Callosobruchus maculatus is an important cowpea pest (Vigna unguiculata) as well as an interesting model to study insect digestive physiology. The larvae of C. maculatus rely on cysteine and aspartic peptidases to digest proteins in their diet. In this work, the global...

Toxicity of cassava wastewater effluents to African catfish: Clarias ...

African Journals Online (AJOL)

The relative lethal and sublethal toxicity of cassava wastewater effluents from a local food factory were investigated on Clarias gariepinus fingerlings using a renewable static bioassay. The physico-chemical characteristics of the cassava wastewater effluents showed a number of deviations from the standards of the Federal ...

Digestive enzymes in the alimentary canal of Clarias anguillaris ...

African Journals Online (AJOL)

Three groups of digestive enzymes were observed in the alimentary canals of the fingerlings and adults of Clarias anguillaris. The enzymes were carbohydrases including amylase, sucrase, lactase and maltase, proteases including peptase, tryptase and peptidase, and lipase. The activities of the protease were found to be ...

Performance of Catfish ( Clarias Gariepinus Burchell, 1822) Fed ...

African Journals Online (AJOL)

The effect of boiled mango seed kernel (MSK) as substitute for maize in diets of catfish (Clarias gariepinus) fingerlings was investigated using four diets were formulated such that T2 , T3 and T4 contained boiled MSK as replacement for maize at 20%, 40% and 60% inclusion levels respectively, while T1 (control) contained ...

The interactive effect of entomopathogenic nematode, Steinernema carpocapsae (Weiser) and gamma radiation ori callosobruchus maculatus (F.) and their biochemical Effects

International Nuclear Information System (INIS)

EI-Orabi, M.N.; Slwfei, D.M.Y.; Amer, A.M.

2007-01-01

Cowpea weevil, Callosobruchus maculatus (F.) adults were infected with entomopathogenic nematodes, Steinernema carpocapsae (Weiser) for evaluating their potential for suppressing this insect pest. Morality percentage of un-irradiated C. maculatus infected with irradiated nematodes decreased at higher doses of gamma irradiation. The results generally Indicated that the reduction of mortality was directly related to gamma irradiation. The results indicated that infestation intensity decreased at higher doses of gamma irradiation when irradiated nematodes infected the irradiated or non-irradiated C. maculatus. Protein content of irradiated C. maculatus adults infected with nematodes showed a slight decrease by increasing radiation dose and time elapsed from infection. Comparing the protein bands at different time intervals for all tested dosage used showed absence of some bands and reduction in the intensity of the others

Inhibition of hatchability of African catfish (Clarias gariepinus) eggs ...

African Journals Online (AJOL)

To diagnose the impact of rainfall and temperature range on hatchability of Clarias gariepinus eggs incubated in hapas and in outdoor basins, some incubating ... Measures to ensure that on-farm incubation systems are free from turbidity, wide temperature fluctuations and anoxia, were thus highlighted as prerequired for ...

Nasal cavity of the farmed african catfish Clarias gariepinus ...

African Journals Online (AJOL)

The nasal cavity microanatomy of farmed fingerlings of African catfish, Clarias gariepunus was investigated to fill existing knowledge gap on its histology from available literatures. This becomes very important as no gustatory cell was reported from previous researches on the fingerling digestive tract. A slice of nasal cavity of ...

Indian Americans at Mille Lacs.

Science.gov (United States)

Holbert, Victoria L.; And Others

The Training Center for Community Programs prepared a report on the Mille Lacs (Chippewa) Reservation in Minnesota. Data for the report were from 2 separate sources: a survey conducted by the Training Center with the assistance of the Mille Lacs community action program (1967) and an attitudinal survey conducted by Victoria Holbert during 1969.…

In vivo expression of the lacY gene in two segments leads to functional lac permease

International Nuclear Information System (INIS)

Bibi, E.; Kaback, H.R.

1990-01-01

The lacY gene of Escherichia coli was cut into two approximately equal-size fragments with Afl II and subcloned individually or together under separate lac operator/promoters in plasmid pT7-5. Under these conditions, lac permease is expressed in two portions: (i) the N-terminal portion (the N terminus, the first six putative transmembrane helices, and most of putative loop 7) and (ii) the C-terminal portion (the last six putative transmembrane helices and the C terminus). Cells harboring pT7-5 encoding both fragments transport lactose at about 30% the rate of cells expressing intact permease to a comparable steady-state level of accumulation. In contrast, cells expressing either half of the permease independently do not transport lactose. As judged by [ 35 S]methionine labeling and immunoblotting, intact permease in completely absent from the membrane of cells expressing lacY fragments either individually or together. Thus, transport activity must result from an association between independently synthesized pieces of lac permease. When the gene fragments are expressed individually, the N-terminal portion of the permease is observed inconsistently, and the C-terminal portion is not observed. When the gene fragments are expressed together, polypeptides identified as the N- and C-terminal moieties of the permease are found in the membrane. It is concluded that the N- or C-terminal halves of lac permease are proteolyzed when synthesized independently and that association between the two complementing polypeptides leads to a more stable, catalytically active complex

Haematological changes in the blood of cultured Clarias gariepinus ...

African Journals Online (AJOL)

This study investigated the artifactual changes in the haematological values of Clarias gariepinus blood stored at room (32oC) and refrigerator (4oC) temperatures. Blood samples were collected from 12 apparently healthy fish weighing between 0.8 and 1kg. Samples were divided into two parts immediately after collection ...

Efficacy of plant extracts against the cowpea beetle, Callosobruchus maculatus

NARCIS (Netherlands)

Boeke, S.J.; Barnaud, B.; Loon, van J.J.A.; Kossou, D.K.; Huis, van A.; Dicke, M.

2004-01-01

Traditionally used African plant powders, with a known effect against the cowpea beetle Callosobruchus maculatus in stored cowpea, were extracted with water. The extracts, 13 volatile oils, 2 non-volatile oils and 8 slurries, were evaluated for their toxic and repellent effects against the beetle.

Growth and Survival of Catfish ( Clarias anguillaris ) Juveniles Fed ...

African Journals Online (AJOL)

Juveniles of catfish, Clarias anguillaris (mean weight, 119.8g) were fed unconventional diets for ten weeks in outdoor hapas (net cages, 1m3 dimension) and the growth responses and feed utilization by the juveniles were compared. The experimental diets were (i) live maggots, (ii) live tilapia fry, (iii) commercial catfish feed ...

Influence of cage farming on feeding and reproductive aspects of Pimelodus maculatus Lacépède, 1803 (Siluriformes: Pimelodidae in the Chavantes reservoir, Brazil - doi: 10.4025/actascibiolsci.v36i1.

Directory of Open Access Journals (Sweden)

Heleno Brandão

2013-09-01

Full Text Available This study evaluated the diet and reproductive aspects of the population of Pimelodus maculatus around net cage fish farming in order to assess the possible impacts of this activity. Monthly collections were performed from March 2008 to February 2009 on two populations: one close to the net cages (NC and one from an area not influenced by these cages denominated the “reference site” (RS. Results of the Alimentary Index (AI, Gonadosomatic Index (GSI, reproductive potential and histological analysis were obtained for both NC and RS populations. The population from NC used leftover food (ration that escapes from net cages as the main food item (99.3%. For the RS population, the detritus item was the more important food source (51.7%. The Detrended Correspondence Analysis (DCA showed that the use of food resources was different between the two sites. The reproductive period of the species (indicated by the GSI revealed that the population of the NC showed an extended reproductive period compared to RS. The histology of the ovaries indicated that the specimens in the NC were spawning capable. This study indicates that fish farming activities influence the species P. maculatus in the Chavantes reservoir by adding a new resource to the food web.

Bioaccumulation of heavy metals in fish (tilapia zilli and clarias gariepinus) organs from river Benue, North - Central Nigeria

International Nuclear Information System (INIS)

Eneji, I.S.; Ato, R.S.; Annune, P.A.

2011-01-01

Heavy metals concentrations were determined in fish organs of Tilapia zilli and Clarias gariepinus from River Benue along Makurdi metropolis sing atomic absorption spectrophotometer. The results indicated that Tilapia zilli gills contained the highest concentration (52.2%) of all the detected heavy metals, followed by the intestine (26.3%), while the muscle tissues appeared to be the least preferred site for the bioaccumulation of metals as the lowest metal concentration (21.5%) were detected in this tissue. Similarly, the Clarias gariepinus gills contained the highest concentration (40.3%) of all the detected heavy metals, followed by the intestine (31.6%), while the muscle tissue (28.1%) was the lowest. The trend of heavy metals concentration can be represented as: Cr > Zn > Cu > Fe > Mn > Cd > Pb for Tilapia zilli, while that of Clarias gariepinus was Cr > Zn > Fe > Cu > Mn > Cd > Pb. Tilapia zilli showed high bioaccumulation factors of 244, 229 and 178 for Cr, Zn and Cu, respectively. Claria gariepinus showed 232, 226 and 151 for Cr, Zn and Fe, respectively. This suggests that the fish samples could be used to monitor Cr and Zn pollution levels in the River Benue. (author)

Responses of the African catfish Clarias gariepinus to long-term ...

African Journals Online (AJOL)

... environment by pesticides results in a decrease in fish productivity and may elevate concentrations of undesirable chemicals in edible fish tissues. The effects of long-term exposure of Clarias gariepinus juveniles to sublethal concentrations of glyphosate and paraquat, two commonly used herbicides, for eight weeks were ...

Smoking Impact on the Microbial Load of Clarias gariepinus ...

African Journals Online (AJOL)

Effects of different smoking methods on microbial load on freshly collected freshwater mud fish, Clarias gariepinus samples from Oyo State Fisheries Department, Ibadan in South-Western Nigeria was carried out. Seventy-two C. gariepinus (505 ± 0.45g and 25.5 ± 1.30cm) were collected and sorted into 4 groups. 10 fish ...

Length-weight relationship and condition factor of clarias gariepinus ...

African Journals Online (AJOL)

Length-Weight relationship and condition factor of Clarias gariepinus and Tilapia Zillii were studiedin lake Alau and Monguno hatchery, both in Borno State of Nigeria, for a period of two weeks. A total of 98 C. gariepinus and 140. T. zillii were measured. The length-weight regression coefficient (b) for both fishes in lake Alau ...

Heavy metal contamination of Clarias gariepinus from a lake and ...

African Journals Online (AJOL)

Adult Clarias gariepinus (African Catfish) were purchased from Eleiyele Lake and Zartech fish farm in Ibadan. Water samples were also collected in February (dry season) and June (rainy season), 2002. Gill, bone, intestine, muscle and water samples were analyzed for five metals: manganese, copper, zinc, iron, and ...

Fresh fish ( Clarias gariepinus ) marketing system in major towns of ...

African Journals Online (AJOL)

This study was carried out to investigate marketing system, market channel, nature of costs, market margins and the factors determining the marketing profit of fresh fish (Clarias gariepinus) in major towns in Ibarapa Zone, Oyo state. Data were collected through the use of questionnaire administered to the fish traders.

Microbial flora of Clarias Gariepinus in the early stages of ...

African Journals Online (AJOL)

A study was carried out to establish the microbial flora in farmed Clarias gariepinus hatchery systems. Enumeration of total aerobic heterotrophic bacteria and fungi, total coliforms, Salmonella spp. Vibrio spp. and Aeromonas hydrophila from eggs (fertilized and unfertilized), larvae, fry, fry feed and tank water showed that ...

Chemo-enzymatic modification of poly-N-acetyllactosamine (LacNAc oligomers and N,N-diacetyllactosamine (LacDiNAc based on galactose oxidase treatment

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Christiane E. Kupper

2012-05-01

Full Text Available The importance of glycans in biological systems is highlighted by their various functions in physiological and pathological processes. Many glycan epitopes on glycoproteins and glycolipids are based on N-acetyllactosamine units (LacNAc; Galβ1,4GlcNAc and often present on extended poly-LacNAc glycans ([Galβ1,4GlcNAc]n. Poly-LacNAc itself has been identified as a binding motif of galectins, an important class of lectins with functions in immune response and tumorigenesis. Therefore, the synthesis of natural and modified poly-LacNAc glycans is of specific interest for binding studies with galectins as well as for studies of their possible therapeutic applications. We present the oxidation by galactose oxidase and subsequent chemical or enzymatic modification of terminal galactose and N-acetylgalactosamine residues of poly-N-acetyllactosamine (poly-LacNAc oligomers and N,N-diacetyllactosamine (LacDiNAc by galactose oxidase. Product formation starting from different poly-LacNAc oligomers was characterised and optimised regarding formation of the C6-aldo product. Further modification of the aldehyde containing glycans, either by chemical conversion or enzymatic elongation, was established. Base-catalysed β-elimination, coupling of biotin–hydrazide with subsequent reduction to the corresponding hydrazine linkage, and coupling by reductive amination to an amino-functionalised poly-LacNAc oligomer were performed and the products characterised by LC–MS and NMR analysis. Remarkably, elongation of terminally oxidised poly-LacNAc glycans by β3GlcNAc- and β4Gal-transferase was also successful. In this way, a set of novel, modified poly-LacNAc oligomers containing terminally and/or internally modified galactose residues were obtained, which can be used for binding studies and various other applications.

Food and feeding habits of Clarias gariepinus (burchell 1822) in ...

African Journals Online (AJOL)

Other food items found in the stomach include insects, zooplankton, arthropod parts, detritus and crustaceans which were of secondary importance. Clarias gariepinus in Egbe Reservoir is an omnivore and females had more empty stomachs (55.60%) than the males (44.40%). This gender bias could be due to intra-specific ...

Effect of Dermestes maculatus on the nutritional qualities of two ...

African Journals Online (AJOL)

This study aimed to assess the effect on nutritional composition of two 'Edible Insects' (Larva of Oryctes boas and Rhynchophorus phoenicis) after infestation by Dermestes maculatus. The study was done over a period of six weeks by subjecting these edible insects to different conditions of storage (using pepper and salt).

Aspects of the reproductive biology of hatchery-raised Clarias ...

African Journals Online (AJOL)

The fecundity of four batch weights (10 samples each) of gravid Clarias gariepinus weighing 60 ± 0.17159 g 125 ± 0.15092 g 250 ±0.20683 g and 500 ± 0.15670 g raised from the hatchery was investigated The paired ovary of each fish was dissected out, weighed (g) and its length measured(mm). Each paired ovary was ...

Attraction of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) to four varieties of Lathyrus sativus L. seed volatiles.

Science.gov (United States)

Adhikary, P; Mukherjee, A; Barik, A

2015-04-01

Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) is an important stored grain pest of Lathyrus sativus L. (Leguminosae), commonly known as khesari, in India, Bangladesh and Ethiopia. Volatiles were collected from four varieties, i.e., Bio L 212 Ratan, Nirmal B-1, WBK-14-7 and WBK-13-1 of uninfested khesari seeds, and subsequently identified and quantified by gas chromatography mass spectrometry and gas chromatography flame ionization detector analyses, respectively. A total of 23 volatiles were identified in the four varieties of khesari seeds. In Bio L 212 Ratan and WBK-13-1 seeds, nonanal was the most abundant followed by farnesyl acetone; whereas farnesyl acetone was predominant followed by nonanal in Nirmal B-1 and WBK-14-7 khesari seeds. The olfactory responses of female C. maculatus toward volatile blends from four varieties of khesari seeds, and individual synthetic compounds and their combinations were examined through Y-shaped glass tube olfactometer bioassays. Callosobruchus maculatus showed significant preference for the whole volatile blends from Bio L 212 Ratan seeds compared to whole volatile blends from other three varieties. The insect exhibited attraction to five individual synthetic compounds, 3-octanone, 3-octanol, linalool oxide, 1-octanol and nonanal. A synthetic blend of 448, 390, 1182, 659 and 8114 ng/20 μl methylene chloride of 3-octanone, 3-octanol, linalool oxide, 1-octanol and nonanal, respectively, was most attractive to C. maculatus, and this combination might be used for insect pest management program such as baited traps.

Induction of Triploidy in Clarias Gariepinus by Heat Shock of ...

African Journals Online (AJOL)

Eggs and milt were collected from female and male Clarias gariepinus respectively. Fertilized eggs were given heat-shock at 40 and 41oC for 4.5 minutes duration. The eggs were shocked at different post fertilization periods viz: immediately after fertilization, 2, 3, 4, 5 and 6 mins after fertilization. Percentage hatchability for ...

Effect of herbicide (primextra) on tissue cholesterol level in Clarias ...

African Journals Online (AJOL)

Juvenile Clarias gariepinus were exposed to sub lethal concentrations (0.04, 0.06 and 0.10μg/L) of primextra for 21 days in a static renewal bioassay system. The changes in the tissue cholesterol concentrations were determined every seven days. The result showed that primextra had adverse effect on the tissue ...

African catfish Clarias gariepinus farming practices in North and South 24 Parganas districts of West Bengal, India

OpenAIRE

Thangapalam Jawahar Abraham; Prakash Kumar Mallick; Pradipta Paul

2018-01-01

Clarias gariepinus is widely cultured due to its tolerance to environmental extremes, high production and good feed conversion rate. This communication describes the farming practices of C. gariepinus in North and South 24 Parganas districts of West Bengal. Clarias gariepinus is cultured in ponds of 0.1–0.75 ha, where fingerlings were stocked at a density of 860–1150 cubic meter–1. The current practices of seed transportation were stressful to fish as the majority of the farmers noticed 5–10%...

Growth performance of African catfish (Clarias sp. juvenile fed on the diets containing various chromium content

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H. Aryansyah

2007-07-01

Full Text Available This experiment was conducted to determine the effect of different dietary chromium level on the growth performance of catfish (Clarias sp. juvenile. Five experimental diets contain different chromium level, namely diet A (as a control diet 0.01; B 1.30; C 2.60; D 3.90 and E 5.20 mg/kg diet were used in this experiment. Fish with body weight of  5.57 ± 0.01 g/ind, fed on the experimental diet, twice a day, at satiation. Feeding trial was conducted for 60 days. Based on the evaluation of protein level of the whole body, protein and lipid retention, daily growth rate and feed efficiency, it was concluded that the optimum dietary chromium level for catfish  juvenile was 2.60 mg/kg diet. Keywords: chromium, growth, Clarias sp.   ABSTRAK Penelitian ini dilakukan untuk mengetahui pengaruh pemberian kromium dengan level berbeda terhadap pertumbuhan ikan lele (Clarias sp. juvenil.  Lima jenis pakan yang mengandung kromium berbeda, yaitu pakan A  (kontrol 0,01; B 1,30; C 2,60; D 3,90 dan pakan E 5,20 mg/kg digunakan dalam penelitian ini. Ikan dengan bobot 5,57 ± 0,01 g/ind., diberi pakan 2 kali sehari secara satiasi.  Pemeliharaan ikan dilakukan selama 60 hari.  Berdasarkan analisa retensi protein, kandungan protein dan retensi lemak dalam tubuh ikan lele, disimpulkan bahwa kadar kromium yang optimum untuk juvenil ikan lele adalah 2,60 mg/kg pakan. Kata kunci: kromium, pertumbuhan, Clarias sp.

Field protocol for induction of triploidy in Clarias gariepinus | Nwafili ...

African Journals Online (AJOL)

A simple field protocol for induction of triploidy in Clarias gariepinus using cold shock was developed. The quantity of ice needed to bring temperature of water down to desired temperature was first calculated. Fertilized eggs were then exposed to 5 ºC or 10 ºC at different times. Percentage hatchability for 5 ºC fertilized ...

heavy metal contamination of clarias gariepinus from a lake and fish ...

African Journals Online (AJOL)

Adult Clarias gariepinus (African Catfish) were purchased from Eleiyele Lake and Zartech fish farm in Ibadan. Water samples were also collected in February (dry season) and. June (rainy season), 2002. Gill, bone, intestine, muscle and water samples were analyzed for five metals: manganese, copper, zinc, iron, and ...

The use of trilene- as anesthesia and triquilizer for catfish Clarias ...

African Journals Online (AJOL)

The culture of the African catfish Clarias gariepinus is developing fast that more easier way of handling bigger fish is required both in the transportation and hypophysation/breeding. Such inputs like tranquilizer/anesthesia would help to reduce handling stress thereby reduce injury and death after operation. Trilene ...

Activités insecticides de Striga hermonthica (Del. Benth (Scrophulariaceae sur Callosobrichus maculatus (Fab. (Coleoptera : Bruchidae

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Nacoulma OG.

2006-01-01

Full Text Available Insecticidal activities of Striga hermonthica (Del. Benth (Scrophulariacecae on Callobruchus maculatus (Fab. (Coleptera Bruchidae. This paper deals with insecticidal potentialities of Striga hermonthica (Del. (Scrophulariaceae in protection of cowpea Vigna unguculata (L. Walp against Callosobruchus maculatus (Fab. (Coleoptera: Bruchidae during storage. Crude acetone extract at 0,5% w/w (100 mg of extract for 20 g of grain exhibits 48% of ovicidal effect and then reduces by half emergence rate of adult beetles at the first generation. This extract shows a weak insecticide activity against adults of C. maculatus. Petroleum ether fraction (0,4% w/w of the crude extract reveals ovicidal (51% and larvicidal (72% effects which reduce the emergence rate of adults to only 9%. LD50 and LD90 are monitored during crude extract fractionation to follow ovicidal and larvicidal compounds and to evaluate their efficacy during the isolation procedure. One fraction, mainly composed of two triterpenoid compounds has been identified as responsible of the ovicidal activity of S. hermonthica while the origin of the larvicidal activity hasn’t been identified.

The business of refractive laser assisted cataract surgery (ReLACS).

Science.gov (United States)

Berdahl, John P; Jensen, Matthew P

2014-01-01

Refractive Laser Assisted Cataract Surgery (ReLACS) combines the femtosecond laser with other noncovered tests and services in an attempt to reduce spectacle dependence in combination with cataract surgery. Significant interest is present among ophthalmologists who are considering adopting this technology, however significant capital outlays and continuing expenses can make the decision to adopt ReLACS foreboding. We review the financial considerations of ReLACS and review the trends seen in early adopters of this technology. Recent findings have shown that ReLACS is a growing segment of cataract surgery. Most practices who have implemented the technology have broken even and have a positive outlook on the financial return of implementing the ReLACS program. The average break-even analysis point for practices is around 230 cases a year. ReLACS is growing and appears to be a financial viable approach for many practices.

Effect injection of Ginger Extract on Development and Nucleus position of “Sangkuriang” Catfish Clarias sp. eggs

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M. Zairin Junior

2007-07-01

Full Text Available One of methods could be applied to continuously meet the need of fish fry including catfish (Clarias sp. is artificial propagation by inducing ovulation and spawning.   As an alternative of existing method, in this study, ginger extract was intramuscularly injected to induce development of catfish eggs.  Ginger is known as an important regulator of the balance of arachidonat cycle.  The dose of ginger extract injected was 0, 0.5, 1.0 and 1.5 mL/kg broodstock.  The results of study showed that injection 100% of ginger extracts in all doses was insignificantly inducing development of egg diameter and its nucleus position of catfish.  Other chemicals exist in ginger extract might be functions as an obstacle for egg development of catfish. Keywords: catfish, Clarias sp., ginger, ovulation, egg   ABSTRAK Salah satu cara untuk memenuhi kebutuhan benih ikan termasuk lele (Clarias sp. secara kontinyu adalah penggunaan teknologi pembiakan buatan melalui perangsangan ovulasi dan pemijahan. Sebagai alternatif teknik yang sudah ada, dicobakan perangsangan perkembangan telur ikan lele menggunakan bahan ekstrak jahe yang dilakukan melalui penyuntikan secara intramuskular. Jahe telah dikenal sebagai suatu pengatur penting atas keseimbangan siklus arakidonat. Dosis ekstrak jahe yang disuntikkan adalah 0, 0,5, 1 dan 1,5 mL/kg induk. Penyuntikan 100% ekstrak jahe pada semua dosis perlakuan belum dapat merangsang perkembangan diameter dan posisi inti sel telur ikan lele sangkuriang. Adanya bahan lain yang terdapat pada jahe diduga sebagai penghambat bagi perkembangan telur ikan lele. Kata kunci: Ikan lele, Clarias sp., jahe, ovulasi,  sel telur

Albizia lebbeck Seed Coat Proteins Bind to Chitin and Act as a Defense against Cowpea Weevil Callosobruchus maculatus.

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Silva, Nadia C M; De Sá, Leonardo F R; Oliveira, Eduardo A G; Costa, Monique N; Ferreira, Andre T S; Perales, Jonas; Fernandes, Kátia V S; Xavier-Filho, Jose; Oliveira, Antonia E A

2016-05-11

The seed coat is an external tissue that participates in defense against insects. In some nonhost seeds, including Albizia lebbeck, the insect Callosobruchus maculatus dies during seed coat penetration. We investigated the toxicity of A. lebbeck seed coat proteins to C. maculatus. A chitin-binding protein fraction was isolated from seed coat, and mass spectrometry showed similarity to a C1 cysteine protease. By ELM program an N-glycosylation interaction motif was identified in this protein, and by molecular docking the potential to interact with N-acetylglucosamine (NAG) was shown. The chitin-binding protein fraction was toxic to C. maculatus and was present in larval midgut and feces but not able to hydrolyze larval gut proteins. It did not interfere, though, with the intestinal cell permeability. These results indicate that the toxicity mechanism of this seed coat fraction may be related to its binding to chitin, present in the larvae gut, disturbing nutrient absorption.

Effect of Gamma Rays on Some Aspects of Biological Performance of Callosobrchus maculatus (Fabricius) and Trogoderma granarium (Everts)

International Nuclear Information System (INIS)

Al-Taweel, A.A.; Al-Jowary, S.A.; Mahmmod, E.A.

2007-01-01

The effect of gamma rays on males and females of Callasobruchus maculatus and Trogoderma granarium which were irradiated as 1-3 days old adults was investigated.The results revealed that the percent egg hatch for both pests was zero, and average number of egg (34.2, 21.5) for both pests respectively where their males where irradiated with 0.18 KGy and mated with unirradiated females.While the percent of egg hatch and the average number of egg (zero, 21, 3) respectively when the females where irradiated with 0.18 and 0.15 KGy and mated to unirradiated males for C. maculatus and T. granarium respectively.Furthermore, the results showed that the percent of eggs hatch and average number of egg was (zero,22.7) for C. maculatus when both sexes irradiated with 0.12 KGy and mated together and it was also (zero, 11.5) for T. granarium when both sexes where irradiated with 0.15 KGy mated together

Adsorption Properties of Lac Dyes on Wool, Silk, and Nylon

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Bo Wei

2013-01-01

Full Text Available There has been growing interest in the dyeing of textiles with natural dyes. The research about the adsorption properties of natural dyes can help to understand their adsorption mechanism and to control their dyeing process. This study is concerned with the kinetics and isotherms of adsorption of lac dyes on wool, silk, and nylon fibers. It was found that the adsorption kinetics of lac dyes on the three fibers followed the pseudosecond-order kinetic model, and the adsorption rate of lac dyes was the fastest for silk and the slowest for wool. The activation energies for the adsorption process on wool, silk, and nylon were found to be 107.15, 87.85, and 45.31 kJ/mol, respectively. The adsorption of lac dyes on the three fibers followed the Langmuir mechanism, indicating that the electrostatic interactions between lac dyes and those fibers occurred. The saturation values for lac adsorption on the three fibers decreased in the order of wool > silk > nylon; the Langmuir affinity constant of lac adsorption on nylon was much higher than those on wool and silk.

Haemogram of adult Clarias gariepinus exposed to chronic levels of ...

African Journals Online (AJOL)

Clarias gariepinus (mean weight, 850 ± 60 g) mean length, 38.75 ± 6.7 cm) were exposed individually to four concentrations of Roundup, containing 360g/l glyphosate in the form of 480g/l isopropylamine salt (1.5, 3.0, 4.5 and 6.0 mg/l) and a control (0 mg/l), five replicates per concentration for 70 days in static renewal ...

Toxicity of roundup (a glyphosate product) to fingerlings of Clarias ...

African Journals Online (AJOL)

Acute static renewal bioassays were conducted on fingerling and adult of Clarias gariepinus (mean weight, 1.22 ± 0.6g; mean total length, 5.25 ± 1.25 cm) using the herbicide, Roundup (glyphosate). In the acute study, fingerlings were exposed in triplicate to 0.0, 14.0, 16.0, 18.0, 20.0 22.0, and 24.0 mg/l of the herbicide for ...

Surviving historical Patagonian landscapes and climate: molecular insights from Galaxias maculatus

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Carrea Cecilia

2010-03-01

Full Text Available Abstract Background The dynamic geological and climatic histories of temperate South America have played important roles in shaping the contemporary distributions and genetic diversity of endemic freshwater species. We use mitochondria and nuclear sequence variation to investigate the consequences of mountain barriers and Quaternary glacial cycles for patterns of genetic diversity in the diadromous fish Galaxias maculatus in Patagonia (~300 individuals from 36 locations. Results Contemporary populations of G. maculatus, east and west of the Andes in Patagonia, represent a single monophyletic lineage comprising several well supported groups. Mantel tests using control region data revealed a strong positive relationship when geographic distance was modeled according to a scenario of marine dispersal. (r = 0.69, P = 0.055. By contrast, direct distance between regions was poorly correlated with genetic distance (r = -0.05, P = 0.463. Hierarchical AMOVAs using mtDNA revealed that pooling samples according to historical (pre-LGM oceanic drainage (Pacific vs. Atlantic explained approximately four times more variance than pooling them into present-day drainage (15.6% vs. 3.7%. Further post-hoc AMOVA tests revealed additional genetic structure between populations east and west of the Chilean Coastal Cordillera (coastal vs. interior. Overall female effective population size appears to have remained relatively constant until roughly 0.5 Ma when population size rapidly increased several orders of magnitude [100× (60×-190×] to reach contemporary levels. Maximum likelihood analysis of nuclear alleles revealed a poorly supported gene tree which was paraphyletic with respect to mitochondrial-defined haplogroups. Conclusions First diversifying in the central/north-west region of Patagonia, G. maculatus extended its range into Argentina via the southern coastal regions that join the Pacific and Atlantic oceans. More recent gene flow between northern

Description of Acleotrema maculatus sp. nov. (Monogenea: Diplectanidae infecting the spotted coral grouper Plectropomus maculatus (F:Serranidea from the Red Sea and its histopathological impact

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Kareem Morsy

2014-09-01

Full Text Available Acleotrema maculatus sp. nov. (Monogenea: Diplectanidae was described from the gills of The spotted coral grouper Plectropomus maculatus (F:Serranidea, Forsskal, 1775. Fish were collected from boot landing sites and fishermen at different water locations along the Red Sea at Hurghada City, Egypt. The morphology and morphometric characterization of the recovered worms were described by means of light microscopy. Eight (53.3% out 15 specimens of P. maculatus were infected. Most of the infected fish had very pale gills. Morphologically, the adult worm of A. maculatus sp. nov., possessed a body which was elongated, fusiform with a total length 0.86–0.90 (0.88 ± 0.02 mm, and a maximum width 0.09–0.13 (0.11 ± 0.02 mm at the level of ovary. Haptor, broad, differentiated from the rest of the body, measured 0.04–0.08 (0.06 ± 0.02 mm and provided with continuous rows of squamodiscs. Two pairs of lateral hamuli, three bars and 14 marginal hooklets were also observed. Lateral (dorsal bars two, stout, dumbbell-shaped, measured 0.052–0.056 (0.054 ± 0.002 mm in length. Ventral bar slender, with transverse groove, measured 0.09–0.11 (0.10 ± 0.01 mm in length. Ventral hamuli measured 0.02–0.06 (0.04 ± 0.02 mm in total length with an outer root that was very long measured 0.016–0.02 (0.018 ± 0.002, stout, slightly notched at broad proximal end; inner root was conical and measured 0.013–0.017 (0.015 ± 0.002 mm, with shaft measured 0.025–0.029 (0.027 ± 0.002 mm and point length 0.007–0.009 (0.008 ± 0.002 mm. Dorsal hamuli measured 0.034–0.038 (0.036 ± 0.002 in total length; base large, stout, with only lateral rudiment of roots; blade and point were long and curved with shaft length measured 0.024–0.028 (0.026 ± 0.002 mm and 0.02–0.06 (0.04 ± 0.02 mm point length. The worm is hermaphrodite, male copulatory organ measured 0.058–0.062 (0.060 ± 0.002 mm in length with a sclerotized part composed of

Resistência de genótipos de feijão-caupi [Vigna unguiculata (L. Walp.] ao Ataque do Caruncho Callosobruchus maculatus (Fabr. (Coleoptera: Chrysomelidae

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Westerllanya Medeiros

2017-04-01

Abstract. The Cowpea weevil Callosobruchus maculatus (Fabr. is considered the main Prague during storage of grains of Cowpea [Vigna unguiculata (L. Walp.]. Due to the economic losses caused by this insect, is of paramount importance to develop studies to select varieties resistant to this pest. In this study assessed the effect of genotypes of V. unguiculata about the behavior and the development of C. maculatus in two consecutive generations. The study was conducted in laboratory with conditions of temperature and relative humidity monitored, in completely randomized design using BRS Epace 10, Capela, BRS Urubuquara, BRS Pajeu, Itaim, BRS Rouxinol, Pingo de ouro, BRS Corujinha, IT85 F-2687 and BR 17 Gurguéia genotypes with eight repetitions. In each genotype were confined 10 adults of c. maculatus for it was held the oviposition. After a period of five days, the adults were removed from the pots containing the genotypes. Waited-if the emergence of adults (first generation and new infestation was held in the same access to obtain the second generation. The parameters evaluated were number of eggs, egg viability, total number of adults emergency, viability of immature phase, average period of development and dry weight of adults. IT85 F2687 genotype presented resistance of non-preference for oviposition and the genotypes BR 17 Gurguéia and BRS Urubuquara presented antibiose type resistance in relation to C. maculatus. BR 17 Gurguéia genotype was the strongest among the genotypes studied in relation to c. maculatus. The genotypes Capela and Itaim were characterized as susceptible to C. maculatus.

Utilização das brânquias de Pimelodus maculatus (Lacèpéde, 1803 (Siluriformes; Pimelodidae como biomarcador de poluição no reservatório da UHE Marechal Mascarenhas de Moraes, Minas Gerais, Brasil.

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Diego José Nogueira

2011-07-01

Full Text Available http://dx.doi.org/10.5007/2175-7925.2011v24n3p51 As brânquias dos peixes são biomarcadores da toxicidade ambiental que, frequentemente, são utilizados na avaliação dos impactos causados por xenobióticos. O presente estudo visa avaliar a contaminação do reservatório Marechal Mascarenhas de Moraes, através da estimativa do índice de alterações morfológicas nas brânquias do Pimelodus maculatus causadas por agentes tóxicos. Os exemplares de P. maculatus foram co­letados em três pontos do reservatório da UHE Marechal Mascarenhas de Moraes. No próprio local de coleta, imediatamente, as brânquias dos indivíduos coletados foram retiradas e fixadas com Bouin. Estas foram coradas com Hematoxilina-Eosina para análise em microscopia de luz. A quantificação das alterações foi realizada por estereologia, e os índices das alterações foram estimados, classificando-se as lesões de moderado a graves nos três pontos de estudo.

'Cand. Actinochlamydia clariae' gen. nov., sp. nov., a unique intracellular bacterium causing epitheliocystis in catfish (Clarias gariepinus in Uganda.

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Andreas Steigen

Full Text Available BACKGROUND AND OBJECTIVES: Epitheliocystis, caused by bacteria infecting gill epithelial cells in fish, is common among a large range of fish species in both fresh- and seawater. The aquaculture industry considers epitheliocystis an important problem. It affects the welfare of the fish and the resulting gill disease may lead to mortalities. In a culture facility in Kampala, Uganda, juveniles of the African sharptooth catfish (Clarias gariepinus was observed swimming in the surface, sometimes belly up, showing signs of respiratory problems. Histological examination of gill tissues from this fish revealed large amounts of epitheliocysts, and also presence of a few Ichthyobodo sp. and Trichodina sp. METHODS AND RESULTS: Sequencing of the epitheliocystis bacterium 16S rRNA gene shows 86.3% similarity with Candidatus Piscichlamydia salmonis causing epitheliocystis in Atlantic salmon (Salmo salar. Transmission electron microscopy showed that the morphology of the developmental stages of the bacterium is similar to that of members of the family Chlamydiaceae. The similarity of the bacterium rRNA gene sequences compared with other chlamydia-like bacteria ranged between 80.5% and 86.3%. Inclusions containing this new bacterium have tubules/channels (termed actinae that are radiating from the inclusion membrane and opening on the cell surface or in neighbouring cells. CONCLUSIONS: Radiation of tubules/channels (actinae from the inclusion membrane has never been described in any of the other members of Chlamydiales. It seems to be a completely new character and an apomorphy. We propose the name Candidatus Actinochlamydia clariae gen. nov., sp. nov. (Actinochlamydiaceae fam. nov., order Chlamydiales, phylum Chlamydiae for this new agent causing epitheliocystis in African sharptooth catfish.

Broad band energy distribution of UV-bright BL Lac objects

International Nuclear Information System (INIS)

Maraschi, L.; Tanzi, E.G.; Treves, A.

1984-01-01

IUE satellite data in the 1200-2000 and 1900-3200 A intervals of BL Lac objects are analyzed in terms of two discernible groups. A total of 25 BL Lac objects were observed, with differences between groups displayed in terms of the power slope of the energy of the UV emissions, i.e., slopes of 1 and 2. Comparisons of the spectra with those of quasars showed that quasars have a small spectral index in the 1000-6000 A band and no correlation exists between the spectral index and UV flux of the BL Lac objects. The comparisons underscore the lack of a thermal component for BL Lac objects. Steep spectral components in both BL Lac objects and highly polarized quasars emissions could both be due to synchrotron emission. Compton scattering of relativistic electrons off synchrotron photons could produce the X ray emissions. 44 references

Broad band energy distribution of UV-bright BL Lac objects

Energy Technology Data Exchange (ETDEWEB)

Maraschi, L.; Tanzi, E.G.; Treves, A.

1984-01-01

IUE satellite data in the 1200-2000 and 1900-3200 A intervals of BL Lac objects are analyzed in terms of two discernible groups. A total of 25 BL Lac objects were observed, with differences between groups displayed in terms of the power slope of the energy of the UV emissions, i.e., slopes of 1 and 2. Comparisons of the spectra with those of quasars showed that quasars have a small spectral index in the 1000-6000 A band and no correlation exists between the spectral index and UV flux of the BL Lac objects. The comparisons underscore the lack of a thermal component for BL Lac objects. Steep spectral components in both BL Lac objects and highly polarized quasars emissions could both be due to synchrotron emission. Compton scattering of relativistic electrons off synchrotron photons could produce the X ray emissions. 44 references.

Infrared polarimetry and photometry of BL Lac objects. 3

Energy Technology Data Exchange (ETDEWEB)

Holmes, P A; Brand, P W.J.L. [Edinburgh Univ. (UK). Dept. of Astronomy; Impey, C D [Hawaii Univ., Honolulu (USA). Inst. for Astronomy; Williams, P M [UKIRT, Hilo, HI (USA)

1984-10-15

The data presented here is part of a continuing monitoring programme of BL lac objects with J, H and K photometry and polarimetry. A total of 30 BL Lac objects have now been observed photometrically. Infrared polarimetry has also been obtained for 24 of these objects. The sample is sufficiently large to examine statistically, and several important correlations have emerged. Internight variations and wavelength dependence of polarization indicate that BL Lac objects, as a class, may be understood in terms of a relatively simple two-component model.

The comparison between LAC and ALA

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Tzu-heng Chiu

2000-12-01

Full Text Available A good library association serves its members, improves the librarianship, and helps library institutions achieving their missions. This article describes the history, missions and goals, organization structure, membership, financial sources, professional activities, publication, and website of the Library Association of China (LAC and American Library Association (ALA, respectively. Considering social / cultural / political differences between Taiwan and the United Sates, the author then compares these two library associations from the eight factors mentioned above. At the end, suggestions for the LAC are proposed.[Article content in Chinese

Clustering environments of BL Lac objects

Science.gov (United States)

Wurtz, Ronald; Ellingson, Erica; Stocke, John T.; Yee, H. K. C.

1993-01-01

We report measurements of the amplitude of the BL Lac galaxy spatial covariance function, B(gb), for the fields of five BL Lacertae objects. We present evidence for rich clusters around MS 1207+39 and MS 1407+59, and confirm high richness for the cluster containing H0414+009. We discuss the ease of 3C 66 A and find evidence for a poor cluster based on an uncertain redshift of z = 0.444. These data suggest that at least some BL Lac objects are consistent with being FR 1 radio galaxies in rich clusters.

The effects of brood stock size on the economy of catfish ( Clarias ...

African Journals Online (AJOL)

Eighty nine ripe female brooders of the catfish, Clarias anguillaris (Body weight. range: 150 1,200 g) were induced to spawn by hormone (Ovaprim®) induced natural spawning technique over a period of 10 weeks. Matching ripe males were used for pairing the females at the ratio of two males to a female. Six ranges of ...

Louisiana SIP: LAC 33:III Ch. 7 - Table 2 - Ambient Air--Methods of Contaminant Measurements; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) to 2011-08-03 (LAd34 - Moved to Section 711 and revised [adds PM-2.5])

Science.gov (United States)

Louisiana SIP: LAC 33:III Ch. 7 - Table 2 - Ambient Air--Methods of Contaminant Measurements; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) to 2011-08-03 (LAd34 - Moved to Section 711 and revised [adds PM-2.5])

Dynamics of ovarian maturation during the reproductive cycle of Metynnis maculatus, a reservoir invasive fish species (Teleostei: Characiformes

Directory of Open Access Journals (Sweden)

Thiago Scremin Boscolo Pereira

Full Text Available In this study, we evaluated the dynamics of ovarian maturation and the spawning processes during the reproductive cycle of Metynnis maculatus. Adult females (n = 36 were collected bimonthly between April 2010 and March 2011. The mean gonadosomatic index (GSI was determined, ovarian and blood samples were submitted for morphometric evaluation and the steroid plasma concentration was determined by ELISA. This species demonstrated asynchronous ovarian development with multiple spawns. This study revealed that, although defined as a multiple spawning species, the ovaries of M. maculatus have a pattern of development with a predominance of vitellogenesis between April and August and have an intensification in spawning in September; in October, a drop in the mean GSI values occurred, and the highest frequencies of post-ovulatory follicles (POFs were observed. We observed a positive correlation between the POF and the levels of 17α-hydroxyprogesterone. Metynnis maculatus has the potential to be used as a source of pituitary tissue for the preparation of crude extracts for hormonal induction; the theoretical period for use is from September to December, but specific studies to determine the feasibility of this approach must be conducted.

Gene-mutation assays in lambda-lacZ transgenic mice : comparison of lacZ with endogenous genes in splenocytes and small intestinal epithelium

NARCIS (Netherlands)

Delft, J.H.M. van; Bergmans, A.; Dam, F.J. van; Tates, A.D.; Howard, L.; Winton, D.J.; Baan, R.A.

1998-01-01

Comparison of results derived from transgenic animal gene-mutation assays with those from mutation analyses in endogenous genes is an important step in the validation of the former. We have used λlacZ transgenic mice to study alkylation-induced mutagenesis in vivo in (a) lacZ and hprt in spleen

Induction of the lac carrier and an associated membrane protein in Escherichia coli

International Nuclear Information System (INIS)

Lagarias, D.M.

1985-01-01

Induction of the lac operon in wild type Escherichia coli strains results in synthesis of a 16 kilodalton inner membrane protein in addition to the known products of the lacZ, lacY and lacA genes. Cells carrying the lacY gene on a plasmid over produce this 16 kilodalton polypeptide as well as the Lac carrier, the membrane protein product of the lacY gene. However, [ 35 S]methionine labeling of minicells carrying the lacY plasmid shows that the 16 kDa protein is not synthesized from the plasmid DNA. The 16 kDa protein was purified and partially characterized. It is an acidic membrane protein of apparent molecular weight 15,800 whose amino terminal sequence (NH 2 -Met-Arg-Asn-Phe-Asp-Leu-) does not correspond to any nucleotide sequence known in lac operon DNA. Using antibody prepared to the purified 16 kDa protein, a quantitative analysis of conditions under which this protein is made was accomplished, and reveals that the amount of 16 kDa protein which appears in the membrane is proportional to lac operon expression. Hybridization of a synthetic oligonucleotide probe complementary to the 5' end of 16 kDa protein mRNA shows that its synthesis is regulated at the level of transcription. A description of attempts to clone this gene is given. Possible functional roles for the 16 kDa protein are discussed

Étude des lésions anatomo-pathologiques des Tilapia et Clarias ...

African Journals Online (AJOL)

SARAH

29 déc. 2014 ... marchés de Lubumbashi témoignent de la mauvaise qualité du produit consommé à cause du danger présenté pour l'homme (toxi- ... Mots- clés: Poisson, Tilapia, Clarias, lésions anatomo-pathologiques, marché, Lubumbashi. ABSTRACT ... sequestration of fishing products that pose a danger to the public.

A dynamic simulation model for growth of the African catfish, Clarias gariepinus (Burchell 1822)

NARCIS (Netherlands)

Machiels, M.A.M.

1987-01-01

In the early '70 it was tried to identify new fish species for aquaculture in Africa. Amongst the most promising candidates was the African catfish. Clariasgariepinus (Burchell 1822). It is an omnivorous fish. which means a wide feeding spectrum. The

Subzero water permeability parameters and optimal freezing rates for sperm cells of the southern platyfish, Xiphophorus maculatus.

Science.gov (United States)

Pinisetty, D; Huang, C; Dong, Q; Tiersch, T R; Devireddy, R V

2005-06-01

This study reports the subzero water transport characteristics (and empirically determined optimal rates for freezing) of sperm cells of live-bearing fishes of the genus Xiphophorus, specifically those of the southern platyfish Xiphophorus maculatus. These fishes are valuable models for biomedical research and are commercially raised as ornamental fish for use in aquariums. Water transport during freezing of X. maculatus sperm cell suspensions was obtained using a shape-independent differential scanning calorimeter technique in the presence of extracellular ice at a cooling rate of 20 degrees C/min in three different media: (1) Hanks' balanced salt solution (HBSS) without cryoprotective agents (CPAs); (2) HBSS with 14% (v/v) glycerol, and (3) HBSS with 10% (v/v) dimethyl sulfoxide (DMSO). The sperm cell was modeled as a cylinder with a length of 52.35 microm and a diameter of 0.66 microm with an osmotically inactive cell volume (Vb) of 0.6 V0, where V0 is the isotonic or initial cell volume. This translates to a surface area, SA to initial water volume, WV ratio of 15.15 microm(-1). By fitting a model of water transport to the experimentally determined volumetric shrinkage data, the best fit membrane permeability parameters (reference membrane permeability to water at 0 degrees C, Lpg or Lpg [cpa] and the activation energy, E(Lp) or E(Lp) [cpa]) were found to range from: Lpg or Lpg [cpa] = 0.0053-0.0093 microm/minatm; E(Lp) or E(Lp) [cpa] = 9.79-29.00 kcal/mol. By incorporating these membrane permeability parameters in a recently developed generic optimal cooling rate equation (optimal cooling rate, [Formula: see text] where the units of B(opt) are degrees C/min, E(Lp) or E(Lp) [cpa] are kcal/mol, L(pg) or L(pg) [cpa] are microm/minatm and SA/WV are microm(-1)), we determined the optimal rates of freezing X. maculatus sperm cells to be 28 degrees C/min (in HBSS), 47 degrees C/min (in HBSS+14% glycerol) and 36 degrees C/min (in HBSS+10% DMSO). Preliminary empirical

Opening Up Natural Resource Based Industries for Innovation (LAC ...

International Development Research Centre (IDRC) Digital Library (Canada)

Opening Up Natural Resource Based Industries for Innovation (LAC). Commodities based on natural resources account for at least half of the exports of two-thirds of the countries in Latin America and the Caribbean (LAC). There is growing concern, however, that existing natural resource-based industries are ...

The influence of supplemented Curcuma in feed formulation to improve growth rate and feed efficiency of catfish (Clarias sp.)

Science.gov (United States)

Ulum, M. M.; Zubaidah, M.; Arief, M.; Prayogo

2018-04-01

Catfish (Clarias sp.) is very potential to be developed as a food fish. The use of the feed additive in feed intended to improve the health, productivity and compliance with animal nutrition. Feed additive is to use ginger are derived from nature.The purpose of this study was to determine the potential increase in feed formulation. The Curcuma effect on growth rate and feed efficiency of catfish (Clarias sp.). The method used experimental methods and design complete random with 4 treatments and 5 replications. The parameters examined in this study aregrowth rate and efficiency feed.The research showed that the ANOVA markedly dissimilar ( Padditive on formulations feed.

Evolutionary behaviour of AGN: Investigations on BL Lac objects and Seyfert II galaxies

Science.gov (United States)

Beckmann, V.

2000-12-01

The evolution and nature of AGN is still one of the enigmatic questions in astrophysics. While large and complete Quasar samples are available, special classes of AGN, like BL Lac objects and Seyfert II galaxies, are still rare objects. In this work I present two new AGN samples. The first one is the HRX-BL Lac survey, resulting in a sample of X-ray selected BL Lac objects. This sample results from 223 BL Lac candidates based on a correlation of X-ray sources with radio sources. The identification of this sample is 98% complete. 77 objects have been identified as BL Lac objects and form the HRX-BL Lac complete sample, the largest homogeneous sample of BL Lac objects existing today. For this sample, redshifts are now known for 62 objects (81 %). In total I present 101 BL Lac objects in the enlarged HRX-BL Lac survey, for which redshift information is available for 84 objects. During the HRX-BL Lac survey I found several objects of special interest. 1ES 1517+656 turned out to be the brightest known BL Lac object in the universe. 1ES 0927+500 could be the first BL Lac object with a line detected in the X-ray region. RX J1211+2242 is probably the the counterpart of the up to now unidentified gamma-ray source 3EG J1212+2304. Additionally I present seven candidates for ultra high frequency peaked BL Lac objects. RX J1054+3855 and RX J1153+3517 are rare high redshift X-ray bright QSO or accreting binary systems with huge magnetic fields. For the BL Lac objects I suggest an unified scenario in which giant elliptical galaxies, formed by merging events of spiral galaxies at z > 2, start as powerful, radio dominated BL Lacs. As the jet gets less powerful, the BL Lacs start to get more X-ray dominated, showing less total luminosities (for z definition to objects with a calcium break up to 40%, but do not support for the HBL the idea of allowing emission lines in the spectra of BL Lac galaxies. A way to find high redshift BL Lac objects might be the identification of faint X

Effect of body size and temperature on respiration of Galaxias maculatus (Pisces: Galaxiidae)

Science.gov (United States)

Milano, D.; Vigliano, P.H.; Beauchamp, David A.

2017-01-01

Body mass and temperature are primary determinants of metabolic rate in ectothermic animals. Oxygen consumption of post-larval Galaxias maculatus was measured in respirometry trials under different temperatures (5–21°C) and varying body masses (0.1–>1.5 g) spanning a relevant range of thermal conditions and sizes. Specific respiration rates (R in g O2 g−1 d−1) declined as a power function of body mass and increased exponentially with temperature and was expressed as: R = 0.0007 * W −0.31 * e 0.13 * T. The ability of this model to predict specific respiration rate was evaluated by comparing observed values with those predicted by the model. Our findings suggest that the respiration rate of G. maculatus is the result of multiple interactive processes (intrinsic and extrinsic factors) that modulate each other in ‘meta-mechanistic’ ways; this would help to explain the species’ ability to undergo the complex ontogenetic habitat shifts observed in the lakes of the Andean Patagonic range.

Growth Performance of Clarias Gariepinus Fed Soaked Moringa Oleifera Leaf Meal

OpenAIRE

Ayegba, E. O

2016-01-01

The present study evaluates the nutritional potential of soaked-dried Moringa oleifera leaf meal in the diet of Clarias gariepinus. Four isonitrogenous (35% crude protein) diets were formulated with Moringa leaf replacing soybean meal at 0%, 10%, 20% and 30%. Result obtained revealed declined in weight gain, specific growth rate, feed conversion efficiency, protein efficiency ratio and apparent net protein utilization as dietary replacement of Moringa leaf meal increased beyond 10%. It is con...

Utilization of fish offal meal in the diet of Clarias gariepinus fingerlings

African Journals Online (AJOL)

A feeding trial was conducted to investigate effect of replacing fish meal (FM) at 0, 25, 50, 75 and 100% with fish offal meal (FOM) in the diets of Clarias gariepinus fingerlings. At the start of experiment, ten glass aquaria of size 70 cm x 45 cm x 40 cm/each, filled with well water up to 70 L of its volume were stocked with 100 ...

The African catfish, Clarias gariepinus, a model for the study of reproductive endocrinology in teleosts

NARCIS (Netherlands)

Oordt, P.G.W.J. van; Goos, H.J.Th.

1987-01-01

In their natural habitat African catfish, Clarias gariepinus, show a discontinuous reproductive cycle. This cycle follows changes in the gonadotropic activity of the pituitary. Gonadotropin release has been shown to be under dual hypothalamic control, i.e. a gonadotropin-releasing hormone (GnRH) and

Evidence for an intermediate conformational state of LacY.

Science.gov (United States)

Jiang, Xiaoxu; Guan, Lan; Zhou, Yonggang; Hong, Wen-Xu; Zhang, Qinghai; Kaback, H Ronald

2012-03-20

LacY mutant Cys154 → Gly exhibits a periplasmic-closed crystal structure identical to the WT, but is periplasmic-open in the membrane. The mutant hardly catalyzes transport, but binds galactosides from either side of the membrane with the same affinity and is resistant to site-directed proteolysis relative to the pseudo-WT. Site-directed alkylation was also applied to 11 single-Cys mutants in Cys154 → Gly LacY in right-side-out membrane vesicles or after solubilization and purification in dodecyl-β-D-maltopyranoside (DDM). Unlike the pseudo-WT, Cys replacements on the periplasmic side of the Cys154 → Gly mutant label rapidly in the membrane without sugar, but labeling decreases markedly after the mutant proteins are purified. Thus, Cys154 → Gly LacY likely favors a higher-energy intermediate periplasmic-open conformation in situ, but collapses to a lower-energy periplasmic-closed conformation in DDM after purification. Notably, branched-chain or neopentyl glycol maltoside detergents stabilize Cys154 → Gly LacY in the membrane-embedded form.

The use of lac-type promoters in control analysis

DEFF Research Database (Denmark)

Jensen, Peter Ruhdal; Westerhoff, H. v.; Michelsen, Ole

1993-01-01

experimentally by constructing E. coli strains, in which the chromosomal atp operon is transcribed from the lacUV5 and the tacI promoter. We measured the concentration of the c subunit of H+-ATPase, and found that the expression of this enzyme could be modulated between non-detectable levels and up to five times...... the wild-type level. Thus, in the absence of inducer, no expression of atp genes could be detected when the atp operon was controlled by the lacUV5 promoter, and we estimate that the expression was less than 0.0025 times the wild-type level. We show that the introduction of a lac Y mutation facilitated...

Physico-Mechanical Properties of Coprocessed Excipient MicroceLac® 100 by DM(3) Approach.

Science.gov (United States)

Haware, Rahul V; Kancharla, Joseph P; Udupa, Aishwarya K; Staton, Scott; Gupta, Mali R; Al-Achi, Antoine; Stagner, William C

2015-11-01

To determine the effect of relative humidity (RH) and hydroxypropyl methylcellulose (HPMC) on the physico-mechanical properties of coprocessed MacroceLac(®) 100 using 'DM(3)' approach. Effects of RH and 5% w/w HPMC on MacroceLac(®) 100 Compressibility Index (CI) and tablet mechanical strength (TMS) were evaluated by 'DM(3)'. The 'DM(3)' approach evaluates material properties by combining 'design of experiments', material's 'macroscopic' properties, 'molecular' properties, and 'multivariate analysis' tools. A 4X4 full-factorial experimental design was used to study the relationship of MacroceLac(®) 100 molecular properties (moisture content, dehydration, crystallization, fusion enthalpy, and moisture uptake) and macroscopic particle size and shape on CI and TMS. A physical binary mixture (PBM) of similar composition to MacroceLac(®) 100 was also evaluated. Multivariate analysis of variance (MANOVA), principle component analysis, and partial least squares (PLS) were used to analyze the data. MANOVA CI ranking was: PBM-HPMC > PBM > MicroceLac(®)100 > MicroceLac(®)100-HPMC (p TMS values were lower than MicroceLac(®)100 and MicroceLac(®)100-HPMC (p TMS. Significant MicroceLac(®)100 changes occurred with % RH exposure affecting performance attributes. HPMC physical addition did not prevent molecular or macroscopic matrix changes.

Solving a discrete model of the lac operon using Z3

Science.gov (United States)

Gutierrez, Natalia A.

2014-05-01

A discrete model for the Lcac Operon is solved using the SMT-solver Z3. Traditionally the Lac Operon is formulated in a continuous math model. This model is a system of ordinary differential equations. Here, it was considerated as a discrete model, based on a Boolean red. The biological problem of Lac Operon is enunciated as a problem of Boolean satisfiability, and it is solved using an STM-solver named Z3. Z3 is a powerful solver that allows understanding the basic dynamic of the Lac Operon in an easier and more efficient way. The multi-stability of the Lac Operon can be easily computed with Z3. The code that solves the Boolean red can be written in Python language or SMT-Lib language. Both languages were used in local version of the program as online version of Z3. For future investigations it is proposed to solve the Boolean red of Lac Operon using others SMT-solvers as cvc4, alt-ergo, mathsat and yices.

Infrared polarimetry and photometry of BL Lac objects

Energy Technology Data Exchange (ETDEWEB)

Impey, C D; Brand, P W.J.L. [Edinburgh Univ. (UK); Wolstencroft, R D; Williams, P M [Royal Observatory, Edinburgh (UK)

1982-07-01

Infrared polarimetry and photometry have been obtained for a sample of 18 BL Lac objects. The data covers a period of one year and is part of a continuing monitoring programme; all observations were in the J,H and K wavebands. Large and variable degrees of polarization are a common property of the sample. Two BL Lac objects show wavelength-dependent polarization, with the polarization increasing towards shorter wavelengths, and two objects show evidence for position angle rotations over a five-day period. The relationship between changes in polarized and total flux is also discussed. The BL Lac objects cover an enormous range of infrared luminosity; the three most luminous having Lsub(IR) > 10/sup 46/ erg s/sup -1/ and the other end of the range having infrared luminosities similar to normal elliptical galaxies. These are the first published infrared polarimetric observations for eight of the sample.

Electron beam irradiation: a technology for quarantine disinfestation of green gram seeds against Callsobruchus maculatus

International Nuclear Information System (INIS)

Bhalla, Shashi; Srinivasan, K.; Singh, Subadas; Thakur, Manju; Sharma, S.K.; Pramod, R.; Dwivedi, J.; Bapna, S.C.

2010-01-01

Green gram (Vigna radiata (L.) Wilkzec) an important legume crop in India is grown in 33.4 lakh hectares. India accounts for ∼ 60% of the world's green gram area but contributes only 47% of its production. Major constraint in storage is the pulse beetle Callosobruchus maculatus Fab. (Coleoptera: Bruchidae), which may cause damage upto 100%. It is widespread throughout tropics and sub-tropics with wide host range and also has different strains. Fumigation with methyl bromide (MB) has been the most widely applied management practice for its control. However, the ozone depleting effect of MB has led to restrictions in its use. Therefore, there is a need for an alternative strategy for controlling the pests. Irradiation, an approved technology by International Plant Protection Convention, seems to be a viable non-chemical, residue-free strategy. Therefore, present studies were conducted to see the efficacy of electron beam (EB) irradiation as quarantine disinfestation treatment against green gram seeds infested with different stages of the target pest, C. maculatus

ATIVIDADE INSETICIDA DE PLANTAS MEDICINAIS SOBRE O Callosobruchus maculatus (COLEOPTERA: BRUCHIDAE

Directory of Open Access Journals (Sweden)

Antonia Mirian Nogueira de Moura Guerra

2009-01-01

Full Text Available This study aimed to evaluate the insecticidal activity of eight medicinal plants on Callosobruchus maculatus (F. (Coleoptera: Bruchidae. Plant powder from Rosmarinus officinalis (L. leaves, Peumus boldus (Mol leaves, Matricaria chamomilla (L. flowers, Baccharis trimera (Less. leaves, Camellia sinensis (L. leaves, Thea sinensis (L. leaves, Ilex paraguariensis (St. Hil. leaves, and fruits of Pimpinella anisum (L. were used in the experiment. Bioassays were carried out under constant conditions of temperature (28±2 °C, relative humidity (70±5% and scotophase of 24 hours. Experimental units consisted of 20 grams of cowpea (Vigna unguiculata (L. Walp. grains with 13% wet basis moisture content, 2 g plant powder and ten adult insects, both placed in plastic containers (60 mm in diameter x 60 mm high. The analyzed variables included: insect mortality, oviposition (egg number and instantaneous rate of population growth (ri. The number of dead insects was recorded 5 days after bioassays were started, the egg number was recorded after 12 days, and ri was estimated on the 60th day. All the tested plants had toxicity to C. maculatus. The highest mortality was found in insects treated with P. boldus and I. paraguariensis. Number of eggs and ri also varied significantly among the powders. The lowest mean values for these parameters were recorded in the plots treated with P. boldus, P. anisum and R. officinalis.

Bio-efficacy of gamma irradiation against pulse beetle, Callosobruchus maculatus L. infesting cowpea seeds

International Nuclear Information System (INIS)

Chauhan, Sumit Kumar; Bhalla, S.; Gautam, S.

2015-01-01

The pulse beetle, Callosobruchus maculatus is an important pest of cowpea in storage. It has cosmopolitan distribution with wide host range and also has different strains. It causes 20-60 per cent losses during storage of cowpea. Hazardous environmental effects posed by the chemicals used for its management necessitate the need for an alternative ecofriendly strategy to control the insect. Gamma irradiation seems to be a viable, non-chemical, residue-free, ecofriendly strategy. The experimental insect, C. maculatus was reared on the cowpea seeds under controlled conditions (28±1℃ and 65±5% RH). The freshly emerged adults (about 24-36 h of age) were exposed in very fine thin polythene envelops to gamma radiation at different doses viz., 25, 50, 100, 200, 400, 600 and 800 Gy using Cobalt-60 Gamma irradiation facility at Food Technology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India. The parameters observed included adult mortality, longevity, fecundity of the survivors and adult emergence in F1 generation. Dose dependent insect mortality was observed with immediate mortality at higher doses. High mortality was observed within 24 hour of irradiation. However, complete mortality resulted within five days of irradiation at 600 and 800 Gy as compared to 12 days in control. Adult longevity decreased with increase in radiation dose. The mean longevity decreased from 6.00 days in control to 2.48 days at the highest dose. The eggs laid by the treated adult beetles did not develop into the adults of next generation. Much higher doses were required to kill the adult while the complete sterility (100% sterility) was found even at the lowest dose of 25 Gy. Thus, gamma irradiation has potential to be used as an eco-friendly mitigation measure against C. maculatus. (author)

Beware of your Cre-Ation: lacZ expression impairs neuronal integrity and hippocampus-dependent memory.

Science.gov (United States)

Reichel, J M; Bedenk, B T; Gassen, N C; Hafner, K; Bura, S A; Almeida-Correa, S; Genewsky, A; Dedic, N; Giesert, F; Agarwal, A; Nave, K-A; Rein, T; Czisch, M; Deussing, J M; Wotjak, C T

2016-10-01

Expression of the lacZ-sequence is a widely used reporter-tool to assess the transgenic and/or transfection efficacy of a target gene in mice. Once activated, lacZ is permanently expressed. However, protein accumulation is one of the hallmarks of neurodegenerative diseases. Furthermore, the protein product of the bacterial lacZ gene is ß-galactosidase, an analog to the mammalian senescence-associated ß-galactosidase, a molecular marker for aging. Therefore we studied the behavioral, structural and molecular consequences of lacZ expression in distinct neuronal sub-populations. lacZ expression in cortical glutamatergic neurons resulted in severe impairments in hippocampus-dependent memory accompanied by marked structural alterations throughout the CNS. In contrast, GFP expression or the expression of the ChR2/YFP fusion product in the same cell populations did not result in either cognitive or structural deficits. GABAergic lacZ expression caused significantly decreased hyper-arousal and mild cognitive deficits. Attenuated structural and behavioral consequences of lacZ expression could also be induced in adulthood, and lacZ transfection in neuronal cell cultures significantly decreased their viability. Our findings provide a strong caveat against the use of lacZ reporter mice for phenotyping studies and point to a particular sensitivity of the hippocampus formation to detrimental consequences of lacZ expression. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Optical Spectra Evolution of BL Lac Objects XW Bi1,∗ , BZ Wang2

Indian Academy of Sciences (India)

low-frequency peaked BL Lac objects (LBLs) is steeper than the high- frequency peaked BL Lac ... vision of BL Lac objects. Many investigators .... We are grateful to the Scientific Research Foundation of the Education Department of Yunnan ...

Bioactivity of Powder and Extracts from Garlic, Allium sativum L. (Alliaceae and Spring Onion, Allium fistulosum L. (Alliaceae against Callosobruchus maculatus F. (Coleoptera: Bruchidae on Cowpea, Vigna unguiculata (L. Walp (Leguminosae Seeds

Directory of Open Access Journals (Sweden)

Abiodun A. Denloye

2010-01-01

Full Text Available Laboratory bioassays were conducted to investigate the bioactivity of powders, extracts, and essential oils from Allium sativum L. (Alliaceae and A. fistulosum L. (Liliaceae against adults, eggs, and larvae of Callosobruchus maculatus F. (Coleoptera: Bruchidae. On the basis of 48 hr median lethal toxicity (LC50, test plant powders and extracts from A. sativum were more toxic to C. maculatus adults than those from A. fistulosum. The 48 hr LC50 values for the powder against the test insect species were 9.66 g/kg and 26.29 g/kg for A. sativum and A. fistulosum, respectively. Also the 48 hr LC50 values obtained show that aqueous extracts of the test plant species, 0.11 g/L (A. sativum and 0.411 g/L (A. fistulosum were more toxic to C. maculatus than the corresponding ethanol extracts. There was no significant difference in the toxicity of vapours from the two test plant species against C. maculatus, although A. sativum gave lower values. The study shows that A. sativum and A. fistulosum have potentials for protecting stored cowpea from damage by C. maculatus.

Flat radio-spectrum galaxies and BL Lacs I. Core properties

NARCIS (Netherlands)

Dennett-Thorpe, J; Marcha, MJ

This paper concerns the relationship of BL Lacs and flat-spectrum weak emission-line galaxies. We compare the weak emission-line galaxies and the BL Lacs in a sample of 57 flat-spectrum objects (Marcha et al. 1996), using high-frequency radio and non-thermal optical flux densities, spectral indices

Insecticidal Activity and Chemical Composition of the Morinda lucida Essential Oil against Pulse Beetle Callosobruchus maculatus

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Moses S. Owolabi

2014-01-01

Full Text Available Insecticidal activity of essential oil extracted from Morinda lucida was tested on pulse beetle Callosobruchus maculatus, which is a pest that causes serious damage to several pulses. The insecticidal activity was compared with two pesticides, Phostoxin and Primo-ban-20. 120 mixed sex adult C. maculatus were introduced, along with 30 g of cowpeas. Four concentrations (0.40, 0.20, 0.10, and 0.05 μg/mL of the M. lucida essential oil, Phostoxin, and Primo-ban-20 were tested. Essential oil chemical composition was analyzed by GC-MS. M. lucida essential oil showed a high toxicological effect, producing 100% mortality after 72 hours at a dose of 0.20 μg/mL. M. lucida essential oil had a potent insecticidal activity (LC90 = 0.629 μg/mL compared to both pesticides, Phostoxin (LC90 = 0.652 μg/mL and Primo-ban-20 (LC90 = 0.726 μg/mL, at 24 h. The main compounds of the essential oil were the oxygenated monoterpenoids, 1,8-cineole (43.4%, and α-terpinyl acetate (14.5%, and the monoterpene hydrocarbons, mostly sabinene (8.2% and β-pinene (4.0%. Results clearly indicate that M. lucida essential oil can be used as an effective alternative for pulse beetle C. maculatus control, and it could be tested against other pulse beetles affecting Asia and Africa and throughout the world, thereby reducing use of synthetic pesticides.

Lysines 72, 80 and 213 and aspartic acid 210 of the Lactococcus lactis LacR repressor are involved in the response to the inducer tagatose-6-phosphate leading to induction of lac operon expression.

Science.gov (United States)

van Rooijen, R J; Dechering, K J; Niek, C; Wilmink, J; de Vos, W M

1993-02-01

Site-directed mutagenesis of the Lactococcus lactis lacR gene was performed to identify residues in the LacR repressor that are involved in the induction of lacABCDFEGX operon expression by tagatose-6-phosphate. A putative inducer binding domain located near the C-terminus was previously postulated based on homology studies with the Escherichia coli DeoR family of repressors, which all have a phosphorylated sugar as inducer. Residues within this domain and lysine residues that are charge conserved in the DeoR family were changed into alanine or arginine. The production of the LacR mutants K72A, K80A, K80R, D210A, K213A and K213R in the LacR-deficient L.lactis strain NZ3015 resulted in repressed phospho-beta-galactosidase (LacG) activities and decreased growth rates on lactose. Gel mobility shift assays showed that the complex between a DNA fragment carrying the lac operators and LacR mutants K72A, K80A, K213A and D210A did not dissociate in the presence of tagatose-6-phosphate, in contrast to wild type LacR. Other mutations (K62A/K63A, K72R, K73A, K73R, T212A, F214R, R216R and R216K) exhibited no gross effects on inducer response. The results strongly suggest that the lysines at positions 72, 80 and 213 and aspartic acid at position 210 are involved in the induction of lac operon expression by tagatose-6-phosphate.

Insecticidal activity of 2-tridecanone against the cowpea weevil Callosobruchus maculatus (Coleoptera: Bruchidae

Directory of Open Access Journals (Sweden)

Yussef F.B. Braga

2007-03-01

Full Text Available The effect of 2-tridecanone vapor on the cowpea weevil (Callosobruchus maculatus development was determined. Seeds of cowpea were infested with adults and exposed to different doses of 2-tridecanone isolated from Pilocarpus microphyllus Stapf ex Holm, a plant species native from northeastern Brazil. The pure monoterpene was evaluated both undiluted as well as in the dilutions 1:10, 1:100 and 1:1,000 (v/v. The following parameters of the cowpea weevil life cycle were analyzed in response to decreasing doses of 2-tridecanone: number of eggs laid, percentage of egg hatching on seeds, percentage of adult emergence, adult weight at emergence, mean developmental time and number of adults emerged. Vapor of 2-tridecanone caused a significant (P O efeito dos vapores da 2-tridecanona sobre o caruncho do feijão-de-corda (Callosobruchus maculatus foi avaliado. Sementes de feijão-de-corda infestados com insetos adultos foram expostas a diferentes doses de 2-tridecanona isolada de Pilocarpus microphyllus, uma espécie nativa do Nordeste do Brasil. O monoterpeno puro foi utilizado nas diluições 1:10, 1:100 e 1:1000 (v/v. Os parâmetros da biologia do inseto foram analisados em função da resposta a doses decrescentes de 2-tridecanona: número de ovos postos por fêmea, percentagem de eclosão de ovos, percentagem de emergência de adultos, peso dos adultos recém-emergidos, tempo médio de desenvolvimento e número total de ovos emergidos. Diferenças significativas (P < 0.05 entre as doses de 2-tridecanona testadas foram observadas, para quatro dos seis parâmetros biológicos analisados. Os resultados obtidos indicaram que a 2-tridecanona é tóxica para C. maculatus, reduzindo significativamente (P < 0.05 o número de insetos emergidos após a infestação. Esse efeito foi causado principalmente pela significativa redução observada na eclosão dos ovos expostos ao vapor da substância.

Baseline surveys of Lac Bay benthic and fish communities, Bonaire

NARCIS (Netherlands)

Debrot, A.O.; Hylkema, A.; Vogelaar, W.; Meesters, H.W.G.; Engel, M.S.; Leon, R.; Prud'homme van Reine, W.F.; Nagelkerken, I.

2012-01-01

Lac Bay is a clear-water, 5 m deep shallow tropical lagoon of 7 km2 opening onto the wave and wind exposed east coast of the island of Bonaire, southern Caribbean. Over the last decades land reclamation by mangroves in Lac has been expanding the surface of turbid, saline backwaters into the bay at

The REX survey as a Tool to Test the Beaming Model for BL Lacs

Science.gov (United States)

Caccianiga, A.; della Ceca, R.; Gioia, I. M.; Maccacaro, T.; Wolter, A.

We present the preliminary properties of the BL Lacs discovered in the REX survey (Caccianiga et al. 1998). In particular, we discuss a few sources with optical spectral properties ``intermediate'' between those of BL Lacs and those of elliptical galaxies. These objects could harbour weak (in the optical band) sources of non-thermal continuum in their nuclei and, if confirmed, they could represent the faint tail of the BL Lac population. The existence of such ``weak'' BL Lacs is matter of discussion in recent literature (e.g. Marcha et al. 1996) and could lead to a revision of the defining criteria of a BL Lac and, consequently, of their cosmological and statistical properties.

The Radio-optical Spectra of BL Lacs and Possible Relatives

Science.gov (United States)

Dennett-Thorpe, J.

I consider the suggestion that, in a complete sample of flat-spectrum radio sources with available optical spectra (Marcha et al 1996), the strong emission line objects, or those with passive elliptical spectra are close relatives of the BL Lacs. New observations at four frequencies from 8 to 43GHz are presented, together with evidence for radio variability. Combined with other radio and optical data from the literature, we are able to construct the non-thermal SEDs and use these to address the questions: are the optically passive objects potentially `unrecognised' BL Lacs (either intrinsically weak and/or hidden by starlight)? What is the relationship between the surprising number of strong emission-line objects and the BL Lacs?

Some gamma radiation effects on Callosobruchus maculatus (Fabr., 1775) (Col. Bruchidae)

International Nuclear Information System (INIS)

Walder, J.M.M.

1975-10-01

The effect of gamma irradiation from a Cobalt-60 source on Callosobruchus maculatus (Fabr.) was studied. Experiments showed that at a dose-rate of 9820 rad/hour the LD 75 of egg embryos was 2 Krad the LD 100 of larvae was 3 Krad and the LD 90 of pupae was 20 Krad. Total sterilization of adults irradiated of the pupae stage was 5 Krad. The sterilizing dose of irradiated adults was 8 Krad at a calculated dose-rate of 57.630 rad/hour

Sensitivity of the different developmental stages of Callosobruchus maculatus to gamma irradiation

International Nuclear Information System (INIS)

Olaifa, J.I.; Adebayo, T.A.; Adesanmi, C.A.; Salau, A.M.

1990-01-01

Life stages of the cowpea seed beetle (Callosobruchus maculatus F.) were γ irradiated from a 60 Co source. Arrested development was observed at dosages of 1.0, 4.0, 10.0 and 10.0 Gy in the egg, 1st, 2nd, 3rd and 4th larvae stages respectively while 4.0 Gy induced sterility. Longevity of 2-day old adults was not affected by irradiation of 100 Gy. Preservation of cowpeas by irradiation is discussed. (author)

Organochlorine pesticide levels in Clarias gariepinus from polluted freshwater impoundments in South Africa and associated human health risks

CSIR Research Space (South Africa)

Barnhoorn, IEJ

2014-02-01

Full Text Available There are increasing concerns regarding the safe human consumption of fish from polluted, freshwater impoundments. The aim of this study was to analyse the muscle tissue of the sharptooth catfish Clarias gariepinus for selected organo-chlorine...

Dietary Carnitine maintains energy reserves and delays fatigue of exercised African catfish (Clarias Gariepinus) fed high fat diets

NARCIS (Netherlands)

Ozorio, R.; Ginneken, van V.J.T.; Thillart, van den G.; Verstegen, M.W.A.; Verreth, J.A.J.

2005-01-01

Lipids, together with proteins, are traditionally considered as primary fuels during aerobic swimming. The effects of dietary fat and carnitine supplements and exercise on the energy metabolism of juvenile fish were investigated. One hundred African catfish (Clarias gariepinus) were fed four

EFEKTIVITAS VECTOBAC 12 AS (Bt H-14 DAN Bacillus thuringiensis H-14 TERHADAP VEKTOR MALARIA An. maculatus DI KOBAKAN DESA HARGOTIRTO, KECAMATAN KOKAP, KABUPATEN KULON PROGO

Directory of Open Access Journals (Sweden)

Blondine Ch. P.

2012-09-01

Full Text Available A study using Vectobac 12 AS ( Bt H-14 and Bacillus thuringiensis H-14 local strain was conducted at laboratory Vector and Reservoir Control Research Unit and breeding ponds of Anopheles maculatus in Kokap regency and Kulon Progo district. The objectives of this study are : (1. to detect the efficacy of B. thuringiensis H-14 local strain toward An. maculatus larvae at the laboratory. (2. to measure the effectiveness of B. thuringiensis H-14 local strain dosages 1 x LC95. 5 x LC95 and 10 x LC95 toward An. maculatus at the field. The efficacy test of B. thuringiensis H-14 local strain toward An. maculatus based on to the method proposed by WHO in order to determine the LC50 and LC90 which is computed using the probit analysis at the laboratory. The methods used R thuringiensis H-14 local strain dosages of 2.145 ppm (1 x LC95, 10.724 ppm (5 x LC95 and 21.448 ppm (10 x LC95 respectively were applied 8 ponds with the width of ponds ranging from 0.08 to 0.45 m2, 0.29 to 0.64 m2 and from 0.08-0.79 m2.The results showed, the dosages after 24 hours were 10.22 ppm (LC50, 27.11 ppm (LC90 and 35.75 ppm (LC95. After 48 hours the dosages were needed 7.74 ppm (LC50, 17.06 ppm (LC90 and 21.34 ppm (LC95, The effectiveness o/R thuringiensis H-14 local strain dosages of 2.145ppm (1 x LC95 toward An. maculatus larvae until 50 % survive the same time (7.35 days as B. thuringiensis H-14 (8.14 days dosages of 10.724 ppm (5 x LC95. B. thuringiensis H-14 local strain dosages of 21.448 ppm (10 x LC95 toward An. maculatus larvae until 50 % survive longer time (16.21 days than B. thuringiensis H-14 local strain 1 x LC95 and 5 x LC95 The B. thuringiensis H-14 local strain is effective for controlling mosquitoes larvae

RADIO-WEAK BL LAC OBJECTS IN THE FERMI ERA

Energy Technology Data Exchange (ETDEWEB)

Massaro, F.; Marchesini, E. J. [Dipartimento di Fisica, Università degli Studi di Torino (UniTO), via Pietro Giuria 1, I-10125 Torino (Italy); D’Abrusco, R.; Smith, Howard A. [Smithsonian Astrophysical Observatory, 60 Garden Street, 02138 Cambridge, MA (United States); Masetti, N. [INAF—Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, via Gobetti 101, I-40129, Bologna (Italy); Andruchow, I. [Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque, B1900FWA, La Plata (Argentina)

2017-01-10

The existence of “radio-weak BL Lac objects” (RWBLs) has been an open question, and has remained unsolved since the discovery that quasars could be radio-quiet or radio-loud. Recently, several groups identified RWBL candidates, mostly found while searching for low-energy counterparts of the unidentified or unassociated gamma-ray sources listed in the Fermi catalogs. Confirming RWBLs is a challenging task since they could be confused with white dwarfs (WDs) or weak emission line quasars (WELQs) when there are not sufficient data to precisely draw their broadband spectral energy distribution, and their classification is mainly based on a featureless optical spectra. Motivated by the recent discovery that Fermi BL Lacs appear to have very peculiar mid-IR emission, we show that it is possible to distinguish between WDs, WELQs, and BL Lacs using the [3.4]–[4.6]–[12] μ m color–color plot built using the WISE magnitudes when the optical spectrum is available. On the basis of this analysis, we identify WISE J064459.38+603131 and WISE J141046.00+740511.2 as the first two genuine RWBLs, both potentially associated with Fermi sources. Finally, to strengthen our identification of these objects as true RWBLs, we present multifrequency observations for these two candidates to show that their spectral behavior is indeed consistent with that of the BL Lac population.

RADIO-WEAK BL LAC OBJECTS IN THE FERMI ERA

International Nuclear Information System (INIS)

Massaro, F.; Marchesini, E. J.; D’Abrusco, R.; Smith, Howard A.; Masetti, N.; Andruchow, I.

2017-01-01

The existence of “radio-weak BL Lac objects” (RWBLs) has been an open question, and has remained unsolved since the discovery that quasars could be radio-quiet or radio-loud. Recently, several groups identified RWBL candidates, mostly found while searching for low-energy counterparts of the unidentified or unassociated gamma-ray sources listed in the Fermi catalogs. Confirming RWBLs is a challenging task since they could be confused with white dwarfs (WDs) or weak emission line quasars (WELQs) when there are not sufficient data to precisely draw their broadband spectral energy distribution, and their classification is mainly based on a featureless optical spectra. Motivated by the recent discovery that Fermi BL Lacs appear to have very peculiar mid-IR emission, we show that it is possible to distinguish between WDs, WELQs, and BL Lacs using the [3.4]–[4.6]–[12] μ m color–color plot built using the WISE magnitudes when the optical spectrum is available. On the basis of this analysis, we identify WISE J064459.38+603131 and WISE J141046.00+740511.2 as the first two genuine RWBLs, both potentially associated with Fermi sources. Finally, to strengthen our identification of these objects as true RWBLs, we present multifrequency observations for these two candidates to show that their spectral behavior is indeed consistent with that of the BL Lac population.

Early development of the African catfish Clarias gariepinus (Burchell, 1822), focusing on the ontogeny of selected organs

NARCIS (Netherlands)

Osman, A.G.M.; Wuertz, S.; Mekkawy, Imam A.; Verreth, J.A.J.; Kirschbaum, Frank

2008-01-01

Embryonic development of Clarias gariepinus was studied from oocyte activation to the end of endogenous feeding (164 h post-fertilization, 164 h-PF). The ontogeny of the eyes, the ear, the heart, the digestive tract and the notochord were described histologically: (i) eyes were not pigmented at

Toxicity and repellence of African plants traditionally used for the protection of stored cowpea against Callosobruchus maculatus

NARCIS (Netherlands)

Boeke, S.J.; Baumgart, I.R.; Loon, van J.J.A.; Huis, van A.; Dicke, M.; Kossou, D.K.

2004-01-01

In a search for botanical products to control the main insect pest of stored cowpea, Callosobruchus maculatus, 33 traditionally used African plants were tested in the laboratory for their toxic and repellent effects against this beetle. Toxicity was evaluated measuring life history parameters in a

Biomarkers of Oxidative Stress and Heavy Metal Levels as Indicators of Environmental Pollution in African Cat Fish (Clarias gariepinus) from Nigeria Ogun River

Science.gov (United States)

Farombi, E. O.; Adelowo, O. A.; Ajimoko, Y. R.

2007-01-01

Levels of Zn, Cu, Cd, As, and Pb in the kidney, Liver, Gills and Heart of African cat fish (Clarias gariepinus) from the Ogun River in Ogun State located close to six major industries in the South Western part of Nigeria, were determined using Bulk Scientific Atomic Absorption Spectrophotometer. Fishes were also collected from Government owned fish farm in Agodi, Ibadan which was considered a reference site. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione (GSH) concentration and malondialdehyde (MDA) formation were also determined. The trend of accumulation of the metals in the organs is as follows: Heart - Zn > Cu > Pb > As > Cd; Gills - Zn > Cu > Pb > Cd > As; Kidney - Zn > Cu > Pb > As > Cd; Liver -Zn > Cu > Pb > As > Cd. The order of concentration of the metals in the organs is as follows: Arsenite - Kidney > Liver > Gills > Heart; Zinc - Gills > Liver > Kidney > Heart; Lead- Liver > Kidney > Gills > Heart; Copper- Kidney > Liver > Gills > Heart; Cadmium > Liver > Gills > Kidney > Heart. The levels of heavy metals ranged between 0.25–8.96 ppm in the heart, 0.69– 19.05 ppm in the kidneys, 2.10–19.75 ppm in the liver and 1.95–20.35 ppm in the gills. SOD activity increased by 61% in the liver, 50% in the kidney and in the heart by 28 % while a significant decrease (44%) was observed in the gill of Clarias gariepinus from Ogun river compared to that Agodi fish farm (PCAT activity in the liver, kidney, gills and heart respectively. The levels of GST activities in the liver, kidney and heart of Clarias gariepinus from Ogun river increased by 62%, 72% and 37% respectively (Pfish farm. GSH concentration increased by 81%, 83% and 53% in the liver, kidney and heart respectively but decreased by 44% in the gills. MDA levels of Clarias gariepinus were significantly (Pfish farm. Overall, the results demonstrate that alteration in the antioxidant enzymes, glutathione system and induction of lipid peroxidation

Time-dependent inhomogeneous jet models for BL Lac objects

Science.gov (United States)

Marlowe, A. T.; Urry, C. M.; George, I. M.

1992-05-01

Relativistic beaming can explain many of the observed properties of BL Lac objects (e.g., rapid variability, high polarization, etc.). In particular, the broadband radio through X-ray spectra are well modeled by synchrotron-self Compton emission from an inhomogeneous relativistic jet. We have done a uniform analysis on several BL Lac objects using a simple but plausible inhomogeneous jet model. For all objects, we found that the assumed power-law distribution of the magnetic field and the electron density can be adjusted to match the observed BL Lac spectrum. While such models are typically unconstrained, consideration of spectral variability strongly restricts the allowed parameters, although to date the sampling has generally been too sparse to constrain the current models effectively. We investigate the time evolution of the inhomogeneous jet model for a simple perturbation propagating along the jet. The implications of this time evolution model and its relevance to observed data are discussed.

A NEW GENUS AND SPECIES OF PROTEOCEPHALIDEAN (CESTODA), FROM CLARIAS CATFISHES (SILURIFORMES: CLARIIDAE) IN AFRICA

Czech Academy of Sciences Publication Activity Database

de Chambrier, A.; Scholz, Tomáš; Beletew, M.; Mariaux, J.

2009-01-01

Roč. 95, č. 1 (2009), s. 160-168 ISSN 0022-3395 R&D Projects: GA MŠk LC522; GA ČR GA524/04/0342; GA ČR GA524/08/0885 Institutional research plan: CEZ:AV0Z60220518 Keywords : CESTODA * CLARIAS * AFRICA Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.195, year: 2009

Crisis in LAC : Infrastructure Investment, Employment and the Expectations of Stimulus

OpenAIRE

Schwartz, Jordan; Andres, Luis; Dragoiu, Georgeta

2009-01-01

Infrastructure investment is a central part of the stimulus plans of the Latin America and the Caribbean (LAC) region as it confronts the growing financial crisis. This paper estimates the potential effects on direct, indirect, and induced employment for different types of infrastructure projects with LAC-specific variables. The analysis finds that the direct and indirect short-term employ...

Haematological changes in Bufo maculatus treated with sublethal concentrations of Cadmium

Directory of Open Access Journals (Sweden)

Lawrence Ikechukwu Ezemonye

2011-12-01

Full Text Available Adult Bufo maculatus was exposed to sublethal cadmium concentrations of 0.25, 0.50, 1.00 and 2.00 mg/L. The toxicant from which the cadmium concentrations were prepared was cadmium chloride (CdCl2.H2O. There were three replicate tanks per treatment and three individuals per tank including control groups. The hematologic alterations based on the examination of blood indices during the 28 days of exposure showed that total erythrocyte count (TEC, hematocrit (Hct and hemoglobin (Hb concentration decreased (P<0.05 relative to controls. The decline was concentration- dependent as concentration of cadmium increased. The decline in hemoglobin and hematocrit in the experimental organism could be due to a decrease in the synthesis or release of erythrocytes into the circulation or an increase in the rate of erythrocyte destruction inflicted by cadmium toxicity. There was significant (P<0.05 elevation in total leuko- leukocyte count (TLC with increase in the concen- cyte concentration of cadmium. The increase in total leukocyte count observed in this study could be attributed to a stimulation of the immune system in response to tissue damage caused by cadmium toxicity. The study has shown that the exposure of the Bufo maculatus toad to cadmium can inflict alterations in the hematologic indices, which could induce unfavorable physiological changes in the amphibian, which may lead to death. There is, therefore, the need to protect amphibians in order to sustain the biodiversity in the Nigerian Niger Delta ecological zone.

lac repressor is an antivirulence factor of Salmonella enterica: its role in the evolution of virulence in Salmonella.

Directory of Open Access Journals (Sweden)

Sandeepa M Eswarappa

Full Text Available The genus Salmonella includes many pathogens of great medical and veterinary importance. Bacteria belonging to this genus are very closely related to those belonging to the genus Escherichia. lacZYA operon and lacI are present in Escherichia coli, but not in Salmonella enterica. It has been proposed that Salmonella has lost lacZYA operon and lacI during evolution. In this study, we have investigated the physiological and evolutionary significance of the absence of lacI in Salmonella enterica. Using murine model of typhoid fever, we show that the expression of LacI causes a remarkable reduction in the virulence of Salmonella enterica. LacI also suppresses the ability of Salmonella enterica to proliferate inside murine macrophages. Microarray analysis revealed that LacI interferes with the expression of virulence genes of Salmonella pathogenicity island 2. This effect was confirmed by RT-PCR and Western blot analysis. Interestingly, we found that SBG0326 of Salmonella bongori is homologous to lacI of Escherichia coli. Salmonella bongori is the only other species of the genus Salmonella and it lacks the virulence genes of Salmonella pathogenicity island 2. Overall, our results demonstrate that LacI is an antivirulence factor of Salmonella enterica and suggest that absence of lacI has facilitated the acquisition of virulence genes of Salmonella pathogenicity island 2 in Salmonella enterica making it a successful systemic pathogen.

Control of Cowpea Weevil, Callosobruchus Maculatus (F.) (Coleoptera: Bruchidae), Using Natural Plant Products

OpenAIRE

Tiroesele, Bamphitlhi; Thomas, Kesegofetse; Seketeme, Seipati

2014-01-01

A laboratory study was conducted to investigate the effects of natural products on the reproduction and damage of Callosobruchus maculatus, the cowpea weevil, on cowpea seeds at Botswana College of Agriculture in Gaborone, Botswana. The cowpea variety Blackeye was used in the study. Fifty grams of each plant product (garlic, peppermint and chilies) was added to 500 g of the cowpea seeds. Findings of this experiment revealed that chilies and garlic had negative effects on cowpea weevils for al...

In vivo biocompatibility of p(HPMAm-lac)-PEG hydrogels hybridized with hyaluronan

NARCIS (Netherlands)

Sabbieti, Maria Giovanna; Dubbini, Alessandra; Laus, Fulvio; Paggi, Emanuele; Marchegiani, Andrea; Capitani, Melania; Marchetti, Luigi; Dini, Fabrizio; Vermonden, Tina; Di Martino, Piera; Agas, Dimitrios; Censi, Roberta

2017-01-01

The present study reports on the biocompatibility in vivo after intramuscular and subcutaneous administration in Balb/c mice of vinyl sulphone bearing p(HPMAm-lac1-2)-PEG-p(HPMAm-lac1-2)/thiolated hyaluronic acid hydrogels, designed as novel injectable biomaterials for potential application in the

Can blueshifted Agn spectra explain B L Lac objects

International Nuclear Information System (INIS)

Basu, D.

2009-01-01

B L Lac spectra are almost completely devoid of any emission line, and absorption features are often present based on which redshifts are estimated. Several models have been proposed to explain the spectra, including the unification scheme currently most popular among astronomers. However, there appear to be ambiguities, uncertainties and contradictory results in this model, and many questions remain unanswered. Also, it involves the process of artificially enhancing the continuum to be concentrated to a high level, by the relativistically beaming jet action, in order to submerge the emission lines, partly or completely, to make them appear weak or invisible. Additionally, the sample based on which B L Lac objects have been included in the unification scheme is rather small to be statistically viable. In this context, we present an alternative and much simpler interpretation of the observed spectra of B L Lac objects, both emission and absorption, as blueshifted lines in Agn. Original spectra of fifty six objects available in the current literature are re-analyzed. Nine of these show only a single weak emission line and no absorption feature, while thirty five exhibit no emission feature but several absorption lines, and another twelve show more than one emission line and, in some cases, several absorption lines. It is demonstrated that emission lines in most B L Lac objects are blueshifted out of the visible region, and, hence, not seen at all. Emission lines, when seen, and absorption lines, are blueshifted and are identified with search lines of longer wavelengths that are naturally weak. Blue shifts, in emission and absorption features, are determined for all objects. Various considerations lead to the conclusion that the blue shift interpretation of B L Lac spectra is superior to and more important than the redshift interpretation. A possible explanation of observed blue shifts is presented in the scenario of the ejection process, a well-recognized mechanism

République de Djibouti : lac Assal [بحيرة عسل

OpenAIRE

Pouyllau , Stéphane

2009-01-01

Vue des berges sud-est du lac Assal (République de Djibouti) le 11 novembre 2009. Le Lac Assal est un lac salé endoréique situé au fond du golfe du Ghoubbet-el-Kharab. D'une superficie de 54 km2 et fermé de la mer par le volcan Ardoukôba, sont altitude est de -153m sous le niveau de la mer.

New morphological data on Cucullanus pinnai pinnai (Nematoda) parasitizing Pimelodus maculatus (Pimelodidae) in southeastern Brazil.

Science.gov (United States)

Vieira, Vivian Suane de Freitas; Vieira, Fabiano Matos; Luque, José Luis

2015-01-01

This paper describes the morphology of Cucullanus pinnai pinnai parasitizing Pimelodus maculatus in the Guandu River, Brazil, based on differential interference contrast (DIC) microscopy and scanning electron microscopy (SEM), providing new morphological data about this species of parasite. Nematodes were collected between May and October 2012 from specimens of Pimelodus maculatus in the Guandu River (22°48'2"S, 43°37'35"W), in the state of Rio de Janeiro, Brazil. Some characteristics of specimens of Cucullanus in this study fall within the range of morphological variations of previously studied C. pinnai pinnai. Most of the specimens studied here had excretory pore and deirids located at the posterior end of the oesophagus, a feature not recorded in previous studies of this species. In addition, the size of the gubernaculum was larger than the other specimens previously studied. The SEM and DIC analyses of C. pinnai revealed several morphological details of the cephalic region and the tail papillae. With regard to the polymorphism of C. pinnai, morphological and genetic studies of this cucullanid nematode are needed, involving large numbers of host species and a wide geographical distribution.

Multi-Wave Luminosity of High-Synchrotron-Peaked TeV BL Lacs ...

Indian Academy of Sciences (India)

LIR, Lγ) in the radio, near-infrared and γ-ray wave bands for HSP. TeV BL Lacs. The results show that there are significant intrinsic cor- relations between LR and Lγ and between LIR and Lγ in all states. (high/average/low), and suggest that for HSP TeV BL Lacs, the Syn- chrotron Self-Compton radiation (SSC) is the main ...

Effects of acute stress on aggression and the cortisol response in the African sharptooth catfish Clarias gariepinus

NARCIS (Netherlands)

Manuel, R.; Boerrigter, J.G.J.; Cloosterman, M.; Gorissen, M.; Flik, G.; Bos, van den R.; Vis, van de H.

2016-01-01

African sharptooth catfish Clarias gariepinus were housed under continuous dim light (1lx) or 12L:12D (350-0lx) cycles. The number of skin lesions, as indicator of aggressive acts, and plasma cortisol levels, as indicator of stress-axis activity, were measured at baseline as well as following a

STRUCTURAL ASPECTS REGARDING TO THE IMAGE OF ICE HOTEL BALEA LAC BREND

Directory of Open Access Journals (Sweden)

Marian ZAHARIA

2008-06-01

Full Text Available Applying a poll-based survey provides important information regarding the tourist offer particulars in Bâlea Lac area. On the day the survey is performed its main advantage is also outlined: the fact that this information display a good accuracy, are obtained in a short time span and involving relatively low expenses. Data collection and centralization of the answers provided by interviewed tourists regarding tourism practice in the Bâlea Lac area have led to drawing up distributions that are presented in the paper. Based on the respective information, statistics methods adequate to the study of tourist opinion on the Bâlea Lac Ice Hotel brand image. Several issues have been outlined, regarding the types of respondents based on their category, Romanian or foreigners, from Romania and based on destination countries, function of: the type of stay; the means of information; their answers referring to their first arrival at Bâlea Lac; the degree of destination assessment; their opinion on host reception; their preference for Bâlea Lac; appreciating value for money; age groups; gender; social and professional standing. The image created through the attractions and services provided in the Bâlea Lac tourist area by tourism activities closely related to the Ice Hotel is well appreciated, so that they have opened up a rather favourable expectancy for those willing to come back and for those tempted to try and spend their holidays in the presented hotel.

Multi-wavelength studies of TeV γ-ray emitting BL Lac objects

International Nuclear Information System (INIS)

Kaufmann, Sarah Sabine

2012-01-01

The discovery of TeV γ-ray emission of BL Lac objects gave new insights in the particle acceleration and the emission processes of the highly relativistic jets. To shed light on the conditions in the high energetic jets of the TeV γ-ray emitting BL Lac objects, I have studied in great detail the spectral energy distribution (SED) of sources with different characteristics. BL Lac objects with exceptional very high energy spectra (soft and hard spectra) and with large differences in the emission peak frequencies, to cover the different classes of BL Lac objects, have been chosen. The basic aim of this thesis was, to study with new, simultaneous multi- avelength (MWL) observations, if the emission processes of these extreme cases of TeV BL Lac objects can be explained by the synchrotron Self-Compton (SSC) model which is well established for the class of BL Lac objects at lower energies. We proposed MWL observations in the optical, UV and X-ray regime, to be conducted simultaneous to very high energy observations with the H.E.S.S. experiment, to study the emission processes. Simultaneous observations are crucial, since BL Lac objects are variable at all wavebands. I have analysed the MWL observations and conducted detailed variability and spectral studies in each wavelength range. The different kind of absorption at each wavelength as well as the influence of the host galaxy of the AGN has been considered to obtain the intrinsic jet spectrum. I have then applied the commonly used theoretical jet model, the SSC model, to the SED. I conducted a MWL campaign on a BL Lac object with the softest TeV spectrum, PKS 2005-489, during which it was observed in a very bright X-ray state. The good spectral coverage of the emission peaks allowed a detailed study of the SSC model. The extreme BL Lac object 1ES 0229+200 exhibits a hard intrinsic TeV spectrum. With my MWL campaign I found a clear cut-off in the optical range and therefore a high minimum Lorentz factor is needed to

Multi-wavelength studies of TeV γ-ray emitting BL Lac objects

Energy Technology Data Exchange (ETDEWEB)

Kaufmann, Sarah Sabine

2012-12-21

The discovery of TeV γ-ray emission of BL Lac objects gave new insights in the particle acceleration and the emission processes of the highly relativistic jets. To shed light on the conditions in the high energetic jets of the TeV γ-ray emitting BL Lac objects, I have studied in great detail the spectral energy distribution (SED) of sources with different characteristics. BL Lac objects with exceptional very high energy spectra (soft and hard spectra) and with large differences in the emission peak frequencies, to cover the different classes of BL Lac objects, have been chosen. The basic aim of this thesis was, to study with new, simultaneous multi- avelength (MWL) observations, if the emission processes of these extreme cases of TeV BL Lac objects can be explained by the synchrotron Self-Compton (SSC) model which is well established for the class of BL Lac objects at lower energies. We proposed MWL observations in the optical, UV and X-ray regime, to be conducted simultaneous to very high energy observations with the H.E.S.S. experiment, to study the emission processes. Simultaneous observations are crucial, since BL Lac objects are variable at all wavebands. I have analysed the MWL observations and conducted detailed variability and spectral studies in each wavelength range. The different kind of absorption at each wavelength as well as the influence of the host galaxy of the AGN has been considered to obtain the intrinsic jet spectrum. I have then applied the commonly used theoretical jet model, the SSC model, to the SED. I conducted a MWL campaign on a BL Lac object with the softest TeV spectrum, PKS 2005-489, during which it was observed in a very bright X-ray state. The good spectral coverage of the emission peaks allowed a detailed study of the SSC model. The extreme BL Lac object 1ES 0229+200 exhibits a hard intrinsic TeV spectrum. With my MWL campaign I found a clear cut-off in the optical range and therefore a high minimum Lorentz factor is needed to

Complex genomic rearrangement in CCS-LacZ transgenic mice.

Science.gov (United States)

Stroud, Dina Myers; Darrow, Bruce J; Kim, Sang Do; Zhang, Jie; Jongbloed, Monique R M; Rentschler, Stacey; Moskowitz, Ivan P G; Seidman, Jonathan; Fishman, Glenn I

2007-02-01

The cardiac conduction system (CCS)-lacZ insertional mouse mutant strain genetically labels the developing and mature CCS. This pattern of expression is presumed to reflect the site of transgene integration rather than regulatory elements within the transgene proper. We sought to characterize the genomic structure of the integration locus and identify nearby gene(s) that might potentially confer the observed CCS-specific transcription. We found rearrangement of chromosome 7 between regions D1 and E1 with altered transcription of multiple genes in the D1 region. Several lines of evidence suggested that regulatory elements from at least one gene, Slco3A1, influenced CCS-restricted reporter gene expression. In embryonic hearts, Slco3A1 was expressed in a spatial pattern similar to the CCS-lacZ transgene and was similarly neuregulin-responsive. At later stages, however, expression patterns of the transgene and Slco3A1 diverged, suggesting that the Slco3A1 locus may be necessary, but not sufficient to confer CCS-specific transgene expression in the CCS-lacZ line. (c) 2007 Wiley-Liss, Inc.

The seed coat of Phaseolus vulgaris interferes with the development of the cowpea weevil [Callosobruchus maculatus (F. (Coleoptera: Bruchidae

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Silva Luciana B.

2004-01-01

Full Text Available We have confirmed here that the seeds of the common bean (Phaseolus vulgaris, L. do not support development of the bruchid Callosobruchus maculatus (F., a pest of cowpea [Vigna unguiculata (L. Walp] seeds. Analysis of the testa (seed coat of the bean suggested that neither thickness nor the levels of compounds such as tannic acid, tannins, or HCN are important for the resistance. On the other hand, we have found that phaseolin (vicilin-like 7S storage globulin, detected in the testa by Western blotting and N-terminal amino acid sequencing, is detrimental to the development of C. maculatus. As for the case of other previously studied legume seeds (Canavalia ensiformis and Phaseolus lunatus we suggest that the presence of vicilin-like proteins in the testa of P. vulgaris may have had a significant role in the evolutionary adaptation of bruchids to the seeds of leguminous plants.

Stress and Welfare of African Catfish (Clarias gariepinus Burchell, 1822) in a Coupled Aquaponic System

OpenAIRE

Björn Baßmann; Matthias Brenner; Harry W. Palm

2017-01-01

African catfish (Clarias gariepinus) were investigated for physiological stress parameters to assess the influence of different cultivation techniques on fish welfare. The fish were reared in two conceptually identical recirculating aquaculture systems (RAS) constructed in a greenhouse. One system was combined with a floating raft hydroponic unit to culture cucumbers (Cucumis sativus) only using the process water. The second system remained without the plant cultivation unit and functioned as...

Evaluation of the efficacy of Levo 2.4 Sl against the cowpea beetle, Callosobruchus maculatus (F.) on stored cowpea grains

International Nuclear Information System (INIS)

Osekre, E. A.; Abrahamani, J.; Abudu, D.T.

2013-01-01

The adverse effects of synthetic pesticides on the environment and non-target organisms have necessitated the exploration of other safer and equally effective pesticides for the management of pests. The efficacy of Levo 2.4 SL (Oxymatrine 2.4 SL; Prosular oxamatrine a. i.), a botanical, against Callosobruchus maculatus (F.) infestation on stored cowpea, Vigna unguiculata (L.) (Walp.) was investigated in the insectary of the Entomology Section of the Faculty of Agriculture of the Kwame Nkrumah University of Science and Technology. The effects of Levo on the adult mortality, ovipoistion and F1 progeny of the insect were evaluated. Thus 200 g of cowpea grains were treated with three dosages; 0.01 ml, 0.02 ml and 0.03 ml of Levo 2.4 SL. Betallic Supper 2.5 EC (Primophos methyl and Permethrin a. i.) was used as a check and a control (untreated grains) was also maintained. The mean number of eggs laid and the number of F1 adults that emerged were significantly (P < 0.05) smaller in the Levo treated grains than the control. The higher dosages of Levo 2.4 SL were more effective against C. maculatus infestation and damage. At the end of four months of storage, Levo at all the dosages offered complete protection to the cowpea grains. Levo 2.4 SL at a dosage of 0.02 ml is considered the right dosage that can give optimum protection to cowpea grains against C. maculatus. (au)

Ostrea puelchana (D'Orbigny 1842: a new host of Tumidotheres maculatus (Say, 1818 in northern Patagonia, Argentina Ostrea puelchana D’Orbigny 1842 nuevo hospedador de Tumidotheres maculatus (Say, 1818 en el norte de Patagonia, Argentina

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María del Socorro Doldan

2012-03-01

Full Text Available Tumidotheres maculatus has been reported as a commensal of Mytilus platensis and Atrina seminuda and suggested as a parasite of Aequipecten tehuelchus in San Matías Gulf (SMG. The native flat oyster, Ostrea puelchana, has been studied in SMG for decades, and no crab-oyster association has been reported. In autumn-spring 2009 and 2010, oysters were collected from four banks in SMG, and the occurrence of T. maculatus inside the pallial cavity of O. puelchana was recorded. The prevalence varied between sites, with 0-12.5% at El Sótano, 0-16.7% at Caleta de los Loros, and no crabs found in the samples from Las Grutas and Puerto Lobos. Infected oysters hosted a single crab. Oysters were infested by either one male (47.7% or one female (15.1%. A positive but low correlation was found for male crab size and oyster size. The presence of these crabs inside the oysters could be due to the overlap of the distribution areas of O. puelchana and other bivalve hosts. Our findings may also be a consequence of local fishing. Commercial extraction of traditional hosts may have caused crabs to look for new hosts.En el Golfo San Matías (GSM, Tumidotheres maculatus ha sido registrado como comensal de Mytilus platensis y Atrina seminuda, y se lo ha indicado como parásito de Aequipecten tehuelchus. La ostra plana nativa Ostrea puelchana ha sido objeto de estudio por décadas en el GSM y no existen precedentes sobre una asociación entre las ostras y el cangrejo pinotérido. Durante otoño-primavera de 2009 y de 2010 se recolectaron ostras de cuatro bancos del GSM, registrándose la ocurrencia de T. maculatus en la cavidad paleal de O. puelchana. La prevalencia varió entre los sitios: 0-12,5% en El Sótano, 0-16,7% en Caleta de los Loros; no se encontraron cangrejos en los muestreos en Las Grutas y en Puerto Lobos. Se encontró un único cangrejo por hospedador; las ostras estuvieron infestadas por cangrejos macho (47,7%, o hembras (15,1%. Se encontró una

Genome-Wide SNP Discovery, Genotyping and Their Preliminary Applications for Population Genetic Inference in Spotted Sea Bass (Lateolabrax maculatus.

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Juan Wang

Full Text Available Next-generation sequencing and the collection of genome-wide single-nucleotide polymorphisms (SNPs allow identifying fine-scale population genetic structure and genomic regions under selection. The spotted sea bass (Lateolabrax maculatus is a non-model species of ecological and commercial importance and widely distributed in northwestern Pacific. A total of 22 648 SNPs was discovered across the genome of L. maculatus by paired-end sequencing of restriction-site associated DNA (RAD-PE for 30 individuals from two populations. The nucleotide diversity (π for each population was 0.0028±0.0001 in Dandong and 0.0018±0.0001 in Beihai, respectively. Shallow but significant genetic differentiation was detected between the two populations analyzed by using both the whole data set (FST = 0.0550, P < 0.001 and the putatively neutral SNPs (FST = 0.0347, P < 0.001. However, the two populations were highly differentiated based on the putatively adaptive SNPs (FST = 0.6929, P < 0.001. Moreover, a total of 356 SNPs representing 298 unique loci were detected as outliers putatively under divergent selection by FST-based outlier tests as implemented in BAYESCAN and LOSITAN. Functional annotation of the contigs containing putatively adaptive SNPs yielded hits for 22 of 55 (40% significant BLASTX matches. Candidate genes for local selection constituted a wide array of functions, including binding, catalytic and metabolic activities, etc. The analyses with the SNPs developed in the present study highlighted the importance of genome-wide genetic variation for inference of population structure and local adaptation in L. maculatus.

Distribuição e alimentação de duas espécies simpátricas de piranhas Serrasalmus maculatus e Pygocentrus nattereri (Characidae, Serrasalminae do rio Ibicuí, Rio Grande do Sul, Brasil Distribution and feeding of two sympatric species of piranhas Serrasalmus maculatus and Pygocentrus nattereri (Characidae, Serrasalminae of the Ibicuí river, State of Rio Grande do Sul, Brazil

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Everton R. Behr

2008-12-01

Full Text Available Duas espécies de piranhas ocorrem no rio Ibicuí, um dos principais afluentes do rio Uruguai. Com o objetivo de analisar a distribuição e a alimentação destas espécies, foram realizadas coletas de dezembro de 1999 a janeiro de 2002, utilizando-se diferentes artes de pesca em três pontos do rio, sendo que cada ponto foi amostrado em dois ambientes (lêntico e lótico. Foram capturados 203 indivíduos de Serrasalmus maculatus Kner, 1858 e 86 de Pygocentrus nattereri Kner, 1858, sendo que a maior captura de ambas as espécies ocorreu no ambiente lêntico e próximo ao rio Uruguai, onde P. nattereri parece estar mais concentrada. O número de exemplares capturados por horário não apresentou variações significativas em P. nattereri enquanto que S. maculatus apresentou a maior captura na revisão da meia-noite. Juvenis de S. maculatus (2-4 cm de comprimento padrão consumiram preferencialmente nadadeiras e insetos. Nas demais classes de tamanho de ambas as espécies, restos de peixes foi o alimento predominante, havendo sobreposição alimentar intra e interespecífica nas maiores classes (8-16 cm e >16 cm de comprimento padrão. Não foram constatadas diferenças no índice de repleção entre os horários e os ambientes para as duas espécies.Two species of piranhas occur in the Ibicuí River, one of the main tributaries of the Uruguay River in southern Brazil, Serrasalmus maculatus Kner, 1858 and Pygocentrus nattereri Kner, 1858. In order to analyze the distribution and feeding habits of these species we conducted collecting expeditions from December 1999 to January 2002, using a variety of fishing gears in three sites along the river, both in lentic and lotic habitats. A total of 203 individuals of S. maculatus and 86 of P. nattereri were caught, mostly in lentic habitats and closer to the Uruguay River, were P. nattereri seems to be more concentrated. The number of individuals captured at different times did not show variation in P

Laccase 1 gene from Plutella xylostella (PxLac1) and its functions in humoral immune response.

Science.gov (United States)

Wang, Ze-Hua; Hu, Rong-Min; Ye, Xi-Qian; Huang, Jian-Hua; Chen, Xue-Xin; Shi, Min

Laccase (EC 1.10.3.2) is a phenoloxidase found in many insect species. The Laccase 1 gene from Plutella xylostella (PxLac1) was cloned, and its expression patterns and functions were determined using qPCR and RNAi methods. The results showed that the expression levels of PxLac1 were consistently high in all larval stages, and the most abundant was in the midgut during the 4th instar stage. Moreover, the expression of PxLac1 was up-regulated in response to bacterial infection, and decreased 24 h after being parasitized by Cotesia vestalis. Further analyses indicated that the effect of parasitization on PxLac1 was induced by active C. vestalis Bracovirus (CvBV). Haemocyte-free hemolymph phenoloxidase (PO) activity was suppressed when PxLac1 was treated with RNAi. Our results provide evidence for a connection between the Laccase 1 gene and insect immunity, and revealed that parasitoid polydnavirus suppresses host PO activity via PxLac1 regulation. Copyright © 2018. Published by Elsevier Ltd.

Dynamic model of gene regulation for the lac operon

International Nuclear Information System (INIS)

Angelova, Maia; Ben-Halim, Asma

2011-01-01

Gene regulatory network is a collection of DNA which interact with each other and with other matter in the cell. The lac operon is an example of a relatively simple genetic network and is one of the best-studied structures in the Escherichia coli bacteria. In this work we consider a deterministic model of the lac operon with a noise term, representing the stochastic nature of the regulation. The model is written in terms of a system of simultaneous first order differential equations with delays. We investigate an analytical and numerical solution and analyse the range of values for the parameters corresponding to a stable solution.

Dynamic model of gene regulation for the lac operon

Energy Technology Data Exchange (ETDEWEB)

Angelova, Maia; Ben-Halim, Asma, E-mail: maia.angelova@northumbria.ac.uk, E-mail: asma.benhalim@northumbria.ac.uk [Intelligent Modelling Lab, School of Computing, Engineering and Information Sciences, Northumbria University, Newcastle upon Tyne NE2 1XE (United Kingdom)

2011-03-01

Gene regulatory network is a collection of DNA which interact with each other and with other matter in the cell. The lac operon is an example of a relatively simple genetic network and is one of the best-studied structures in the Escherichia coli bacteria. In this work we consider a deterministic model of the lac operon with a noise term, representing the stochastic nature of the regulation. The model is written in terms of a system of simultaneous first order differential equations with delays. We investigate an analytical and numerical solution and analyse the range of values for the parameters corresponding to a stable solution.

Gamma radiation effects on Callosobruchus Maculatus (Fabr. , 1792) (Coleoptera, Bruchidae)

Energy Technology Data Exchange (ETDEWEB)

Walder, J M.M.

1974-01-01

The effect of gamma irradiation from a Cobalt-60 source on Callosobruchus maculatus (Fabr.) was studied. Experiments showed that at a dose-rate of 9820 +- 300 rad/hour the LD/sub 100/ of egg embryos was 2,2 Krad of larvae 3 Krad of pupae 22,8 Krad. Total sterilization of adults irradiated of the pupal stage was 5 Krad. The sterilizing dose of irradiated adults was 8 krad at a calculated dose-rate of 57.630+-5000 rad/hour, whereas the LD/sub 100/ was 330 krad at a dose-rate of 63650+-1500 rad/hour. It was further verified that the number of eggs laid decrease in the females and diminish in the males as a result of irradiation.

Partial and total fish meal replacement by agricultural products in the diets improve sperm quality in African catfish (Clarias gariepinus)

NARCIS (Netherlands)

Nyina-wamwiza, L.; Milla, S.; Pierrard, M.A.; Rurangwa, E.; Mandiki, S.N.M.; Look, van K.J.W.; Kestemont, P.

2012-01-01

This study investigated the long-term effects of total and partial replacement of dietary fish meal (FM) by a mixture of agricultural products on sperm quality of African catfish Clarias gariepinus. Four isonitrogenous and isoenergetic diets were formulated containing graded levels of either 50% FM

Enzymatic Synthesis of N-Acetyllactosamine (LacNAc Type 1 Oligomers and Characterization as Multivalent Galectin Ligands

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Thomas Fischöder

2017-08-01

Full Text Available Repeats of the disaccharide unit N-acetyllactosamine (LacNAc occur as type 1 (Galβ1, 3GlcNAc and type 2 (Galβ1, 4GlcNAc glycosylation motifs on glycoproteins and glycolipids. The LacNAc motif acts as binding ligand for lectins and is involved in many biological recognition events. To the best of our knowledge, we present, for the first time, the synthesis of LacNAc type 1 oligomers using recombinant β1,3-galactosyltransferase from Escherichia coli and β1,3-N-acetylglucosaminyltranferase from Helicobacter pylori. Tetrasaccharide glycans presenting LacNAc type 1 repeats or LacNAc type 1 at the reducing or non-reducing end, respectively, were conjugated to bovine serum albumin as a protein scaffold by squarate linker chemistry. The resulting multivalent LacNAc type 1 presenting neo-glycoproteins were further studied for specific binding of the tumor-associated human galectin 3 (Gal-3 and its truncated counterpart Gal-3∆ in an enzyme-linked lectin assay (ELLA. We observed a significantly increased affinity of Gal-3∆ towards the multivalent neo-glycoprotein presenting LacNAc type 1 repeating units. This is the first evidence for differences in glycan selectivity of Gal-3∆ and Gal-3 and may be further utilized for tracing Gal-3∆ during tumor progression and therapy.

The introduction of the African catfish Clarias gariepinus (Burchell, 1822 into Brazilian inland waters: a growing threat

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Gecely Rodrigues Alves Rocha

Full Text Available The biology of the introduced species Clarias gariepinus in lagoa Encantada (Ilhéus, Bahia State was studied. Samples were obtained with gillnets between May 2002 and February 2004. All individuals caught exceeded the average length at first maturity cited in literature. Males and females in maturation stages indicate that the species is already established in the lake.

Morphological and molecular data reveal a new species of Neoechinorhynchus (Acanthocephala: Neoechinorhynchidae) from Dormitator maculatus in the Gulf of Mexico.

Science.gov (United States)

Pinacho-Pinacho, Carlos Daniel; Sereno-Uribe, Ana L; García-Varela, Martín

2014-12-01

Neoechinorhynchus (Neoechinorhynchus) mexicoensis sp. n. is described from the intestine of Dormitator maculatus (Bloch 1792) collected in 5 coastal localities from the Gulf of Mexico. The new species is mainly distinguished from the other 33 described species of Neoechinorhynchus from the Americas associated with freshwater, marine and brackish fishes by having smaller middle and posterior hooks and possessing a small proboscis with three rows of six hooks each, apical hooks longer than other hooks and extending to the same level as the posterior hooks, 1 giant nucleus in the ventral body wall and females with eggs longer than other congeneric species. Sequences of the internal transcribed spacer (ITS) and the large subunit (LSU) of ribosomal DNA including the domain D2+D3 were used independently to corroborate the morphological distinction among the new species and other congeneric species associated with freshwater and brackish water fish from Mexico. The genetic divergence estimated among congeneric species ranged from 7.34 to 44% for ITS and from 1.65 to 32.9% for LSU. Maximum likelihood and Bayesian inference analyses with each dataset showed that the 25 specimens analyzed from 5 localities of the coast of the Gulf of Mexico parasitizing D. maculatus represent an independent clade with strong bootstrap support and posterior probabilities. The morphological evidence, plus the monophyly in the phylogenetic analyses, indicates that the acanthocephalans collected from intestine of D. maculatus from the Gulf of Mexico represent a new species, herein named N. (N.) mexicoensis sp. n. Copyright © 2014. Published by Elsevier Ireland Ltd.

VizieR Online Data Catalog: The CLASS BL Lac sample (Marcha+, 2013)

Science.gov (United States)

Marcha, M. J. M.; Caccianiga, A.

2014-04-01

This paper presents a new sample of BL Lac objects selected from a deep (30mJy) radio survey of flat spectrum radio sources (the CLASS blazar survey). The sample is one of the largest well-defined samples in the low-power regime with a total of 130 sources of which 55 satisfy the 'classical' optical BL Lac selection criteria, and the rest have indistinguishable radio properties. The primary goal of this study is to establish the radio luminosity function (RLF) on firm statistical ground at low radio luminosities where previous samples have not been able to investigate. The gain of taking a peek at lower powers is the possibility to search for the flattening of the luminosity function which is a feature predicted by the beaming model but which has remained elusive to observational confirmation. In this study, we extend for the first time the BL Lac RLF down to very low radio powers ~1022W/Hz, i.e. two orders of magnitude below the RLF currently available in the literature. In the process, we confirm the importance of adopting a broader, and more physically meaningful set of classification criteria to avoid the systematic missing of low-luminosity BL Lacs. Thanks to the good statistics we confirm the existence of weak but significant positive cosmological evolution for the BL Lac population, and we detect, for the first time the flattening of the RLF at L~1025W/Hz in agreement with the predictions of the beaming model. (1 data file).

Some effects of gamma radiation in Callosobruchus maculatus (Fabr., 1792) (Coleoptera, Bruchidae); Alguns efeitos da radiacao gama em Callosobruchus maculatus (Fabr., 1792) (Coleoptera, Bruchidae)

Energy Technology Data Exchange (ETDEWEB)

Walder, J M.M.

1975-12-31

The effect of gamma irradiation from a Cobalt-60 source on Callosobruchus maculatus (Fabr.) was studied in this work. Experiments showed that at a dose-rate of 9820 {+-} 300 rad/hour the LD sub(100) of egg embryos was 2,2 krad, of larvae 3 krad and of pupae 22,8 krad. Total sterilization of adults irradiated of the pupal stage was 5 krad. The sterilizing dose of irradiated adults was 8 krad at a calculated dose-rate of 57.630 {+-} 5000 rad/hour, whereas the LD sub(100) was 330 krad at a dose-rate of 63650 {+-} 1500 rad/hour. It was further verified that the number of eggs laid decreased with the irradiation dose. Longevity tended by increase in the females and diminish in the males as a result of irradiation. (author).

A first insight into the barcodes for African diplostomids (Digenea: Diplostomidae): Brain parasites in Clarias gariepinus (Siluriformes: Clariidae)

Czech Academy of Sciences Publication Activity Database

Chibwana, F.D.; Blasco-Costa, Maria Isabel; Georgieva, Simona; Hosea, K.M.; Nkwengulila, G.; Scholz, Tomáš; Kostadinova, Aneta

2013-01-01

Roč. 17, JUL 2013 (2013), s. 62-70 ISSN 1567-1348 R&D Projects: GA ČR GBP505/12/G112 EU Projects: European Commission(XE) 252124 - PARAPOPGENE Institutional support: RVO:60077344 Keywords : Tylodelphys spp. * Diplostomum spp. * Clarias gariepinus * Synodontis nigrita * Tanzania * Africa Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.264, year: 2013

Biomarkers of Oxidative Stress and Heavy Metal Levels as Indicators of Environmental Pollution in African Cat Fish (Clarias gariepinus from Nigeria Ogun River

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Y. R. Ajimoko

2007-06-01

Full Text Available Levels of Zn, Cu, Cd, As, and Pb in the kidney, Liver, Gills and Heart of African cat fish (Clarias gariepinus from the Ogun River in Ogun State located close to six major industries in the South Western part of Nigeria, were determined using Bulk Scientific Atomic Absorption Spectrophotometer. Fishes were also collected from Government owned fish farm in Agodi, Ibadan which was considered a reference site. The activities of superoxide dismutase (SOD, catalase (CAT, glutathione S-transferase (GST, glutathione (GSH concentration and malondialdehyde (MDA formation were also determined. The trend of accumulation of the metals in the organs is as follows: Heart - Zn > Cu > Pb > As > Cd; Gills - Zn > Cu > Pb > Cd > As; Kidney - Zn > Cu > Pb > As > Cd; Liver -Zn > Cu > Pb > As > Cd. The order of concentration of the metals in the organs is as follows: Arsenite - Kidney > Liver > Gills > Heart; Zinc - Gills > Liver > Kidney > Heart; Lead- Liver > Kidney > Gills > Heart; Copper- Kidney > Liver > Gills > Heart; Cadmium > Liver > Gills > Kidney > Heart. The levels of heavy metals ranged between 0.25-8.96 ppm in the heart, 0.69- 19.05 ppm in the kidneys, 2.10-19.75 ppm in the liver and 1.95-20.35 ppm in the gills. SOD activity increased by 61% in the liver, 50% in the kidney and in the heart by 28 % while a significant decrease (44% was observed in the gill of Clarias gariepinus from Ogun river compared to that Agodi fish farm (P<0.001. On the contrary there was 46%, 41%, 50% and 19% decrease in CAT activity in the liver, kidney, gills and heart respectively. The levels of GST activities in the liver, kidney and heart of Clarias gariepinus from Ogun river increased by 62%, 72% and 37% respectively (P<0.001 whereas there was a significant decrease (41% in the gills (P<0.05 compared to that from the Agodi fish farm. GSH concentration increased by 81%, 83% and 53% in the liver, kidney and heart respectively but decreased by 44% in the gills. MDA levels of

PRODUCTION HALIEUTIQUE DU LAC FAE (BASSIN DU SAN ...

African Journals Online (AJOL)

about 5.229 millions CFA for the shrimp production at the rate of 1500 Flkg. .... Figure 1 Lac Fae-Localisation geographique, zones de production, secteurs et ... embankment dam ; d : water intake for regulating the threshold level of water in the.

Evolution and Biophysics of the Escherichia coli lac Operon

Science.gov (United States)

Ray, J. Christian; Igoshin, Oleg; Quan, Selwyn; Monds, Russell; Cooper, Tim; Balázsi, Gábor

2011-03-01

To understand, predict, and control the evolution of living organisms, we consider biophysical effects and molecular network architectures. The lactose utilization system of E. coli is among the most well-studied molecular networks in biology, making it an ideal candidate for such studies. Simulations show how the genetic architecture of the wild-type operon attenuates large metabolic intermediate fluctuations that are predicted to occur in an equivalent system with the component genes on separate operons. Quantification of gene expression in the lac operon evolved in growth conditions containing constant lactose, alternating with glucose, or constant glucose, shows characteristic gene expression patterns depending on conditions. We are simulating these conditions to show context-dependent biophysical sources and costs of different lac operon architectures.

Lead nitrate induced changes in the thyroid physiology of the catfish Clarias batrachus (L)

International Nuclear Information System (INIS)

Katti, S.R.; Sathyanesan, A.G.

1987-01-01

Chronic exposure of Clarias batrachus to sublethal dose of 5 ppm lead nitrate for a period of 150 days impaired thyroid function. Histological observations revealed hypertrophy, increased cell height, vacuolation, and reduction of colloid. The thyrotrophs of the pituitary also exhibited hypertrophy. Radioiodine ( 131 I) uptake was significantly lowered. Fish exposed to 5, 10, and 25 ppm of lead nitrate for 7 days also exhibited significant reduction in 131 I uptake which was dose dependent. These findings suggest that lead nitrate impairs thyroid function involving the hypothalamohypophysiothyroid axis

Water quality and hydrology of the Lac Vieux Desert watershed, Gogebic County, Michigan, and Vilas County, Wisconsin, 2002-04

Science.gov (United States)

Weaver, T.L.; Neff, B.P.; Ellis, J.M.

2005-01-01

Lac Vieux Desert is a prominent 6.6 square-mile lake that straddles the Michigan-Wisconsin border and forms the headwaters of the Wisconsin River. For generations, the Lac Vieux Desert Band of Lake Superior Chippewa Indians have used Lac Vieux Desert and the surrounding area for growing and harvesting wild rice, and hunting and fishing. The Lac Vieux Desert Band is concerned about the impact of lake-stage regulation on hydrology and ecology, and the impact on water quality of development along and near the shore, and recreational watercraft use and sport fishing. In 2005, the U.S. Geological Survey completed a water-resources investigation of the Lac Vieux Desert watershed in cooperation with the Lac Vieux Desert Band of Lake Superior Chippewa Indians.Water quality of Lac Vieux Desert is typical of many lakes in the northern United States. Trophic State Index calculations classify Lac Vieux Desert as a highly productive eutrophic lake. The pH of water in Lac Vieux Desert ranged from 6.5 to 9.5, and specific conductance ranged from 62 to 114 µs/cm. Chloride concentration was less than 1.5 mg/L, indicating little effect from septic-tank or road-salt input. Results indicate that the water can be classified as soft, with hardness concentrations reported as calcium carbonate ranging from 29 to 49 mg/L. Concentrations of calcium, magnesium, chloride, and other dissolved solids ranged from 47 to 77 mg/L. Alkalinity of Lac Vieux Desert ranged from 27 to 38 mg/L.Pervasive aquatic blooms, including a bloom noted during the September 2003 sampling, are apparently common in late summer. Biological productivity at Lac Vieux Desert does not appear to have changed appreciably between 1973 and 2004. In the current study, total phosphorus concentrations ranged from 0.01 to 0.064 mg/L and dissolved nitrite plus nitrate nitrogen concentrations ranged from at, or below detection limit to 0.052 mg/L. Overabundance of nutrients in Lac Vieux Desert, particularly nitrogen and phosphorus

Phenotypic Diversities of Four Populations of Clarias Gariepinus (Siluriformes, Clariidae Obtained from Ogun and Ondo State Waterbodies in South-Western Nigeria

Directory of Open Access Journals (Sweden)

Ola-Oladimeji F. A.

2017-08-01

Full Text Available The study determined the variation in the morphological and meristic features among four populations of Clarias gariepinus Burchell, 1822 obtained from Owena Dam and River Oluwa in Ondo State and Rivers Omo and Ogbere in Ogun State, both in Nigeria. A total of ninety five (95 and one hundred and twenty (120 fish specimens collected from Ondo and Ogun states respectively were measured using standard procedures and the results were analysed using Analysis of variance and multivariate analyses. The results obtained from the ANOVA and Principal Component Analyses of Clarias gariepinus from the four populations revealed heterogeneity for most of their characters. Therefore, the morphological differences between the wild African catfish found in Ondo and Ogun state populations could be linked to genetic differences or environmental factors or a combination of both factors. Hence, this study concluded that the populations are different which could imply high genetic diversity if molecular marker techniques are employed in further studies.

Gamma radiation influence on oviposition and longevity of 'Callosobruchus maculatus' (Fabr., 1972) (Coleoptera, Bruchidae)

International Nuclear Information System (INIS)

Walder, J.M.M.; Wiendl, F.M.

1973-01-01

It was verified that 'Callosobruchus maculatus' (Fabr.), a serious pest attacking seeds of 'Vigna sinensis', is highly susceptible to gamma radiation for sterilization. A dosis of 5 krad causes the egg fertility to decrease from 90% to only 1%. Adults irradiated with 10 krad become totally infertile. Doses of 10 krad and more cause an increase of about 19% in the longevity of females, but decreases the longetivy of males by about 5%. Also, irradiation causes a decrease in the total number of eggs, inversely proportional to the dosage increase [pt

Gamma radiation influence on oviposition and longevity of 'Callosobruchus maculatus' (Fabr. , 1972) (Coleoptera, Bruchidae)

Energy Technology Data Exchange (ETDEWEB)

Walder, J M.M. [Centro de Energia Nuclear na Agricultura, Piracicaba (Brazil); Wiendl, F M [Sao Paulo Univ., Piracicaba (Brazil). Escola Superior de Agricultura Luiz de Queiroz

1973-03-01

It was verified that 'Callosobruchus maculatus' (Fabr.), a serious pest attacking seeds of 'Vigna sinensis', is highly susceptible to gamma radiation for sterilization. A dosis of 5 krad causes the egg fertility to decrease from 90% to only 1%. Adults irradiated with 10 krad become totally infertile. Doses of 10 krad and more cause an increase of about 19% in the longevity of females, but decreases the longevity of males by about 5%. Also, irradiation causes a decrease in the total number of eggs, inversely proportional to the dosage increase.

Spectroscopy of optically selected BL Lac objects and their γ-ray emission

Energy Technology Data Exchange (ETDEWEB)

Sandrinelli, A.; Treves, A.; Farina, E. P.; Landoni, M. [Università degli Studi dell' Insubria, Via Valleggio 11, I-22100 Como (Italy); Falomo, R. [INAF-Osservatorio Astronomico di Padova, Vicolo dell Osservatorio 5, I-35122 Padova (Italy); Foschini, L.; Sbarufatti, B., E-mail: angela.sandrinelli@brera.inaf.it [INAF-Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, I-23807 Merate (Italy)

2013-12-01

We present Very Large Telescope optical spectroscopy of nine BL Lac objects of unknown redshift belonging to the list of optically selected radio-loud BL Lac candidates. We explore their spectroscopic properties and possible link with gamma-ray emission. From the new observations we determine the redshifts of four objects from faint emission lines or from absorption features of their host galaxies. In three cases we find narrow intervening absorptions from which a lower limit to the redshift is inferred. For the remaining two featureless sources, lower limits to the redshift are deduced from the absence of spectral lines. A search for γ counterpart emission shows that six out of the nine candidates are Fermi γ-ray emitters and we find two new detections. Our analysis suggests that most of the BL Lac objects still lacking redshift information are most likely located at high redshifts.

THE CONTRIBUTION OF FERMI -2LAC BLAZARS TO DIFFUSE TEV–PEV NEUTRINO FLUX

Energy Technology Data Exchange (ETDEWEB)

Aartsen, M. G. [Department of Physics, University of Adelaide, Adelaide, 5005 (Australia); Abraham, K. [Physik-department, Technische Universität München, D-85748 Garching (Germany); Ackermann, M. [DESY, D-15735 Zeuthen (Germany); Adams, J. [Dept. of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Aguilar, J. A.; Ansseau, I. [Université Libre de Bruxelles, Science Faculty CP230, B-1050 Brussels (Belgium); Ahlers, M. [Dept. of Physics and Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin, Madison, WI 53706 (United States); Ahrens, M. [Oskar Klein Centre and Dept. of Physics, Stockholm University, SE-10691 Stockholm (Sweden); Altmann, D.; Anton, G. [Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91058 Erlangen (Germany); Andeen, K. [Department of Physics, Marquette University, Milwaukee, WI, 53201 (United States); Anderson, T.; Arlen, T. C. [Dept. of Physics, Pennsylvania State University, University Park, PA 16802 (United States); Archinger, M.; Baum, V. [Institute of Physics, University of Mainz, Staudinger Weg 7, D-55099 Mainz (Germany); Arguelles, C.; Axani, S. [Dept. of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Auffenberg, J. [III. Physikalisches Institut, RWTH Aachen University, D-52056 Aachen (Germany); Bai, X. [Physics Department, South Dakota School of Mines and Technology, Rapid City, SD 57701 (United States); Barwick, S. W., E-mail: thorsten.gluesenkamp@fau.de [Dept. of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Collaboration: IceCube Collaboration; and others

2017-01-20

The recent discovery of a diffuse cosmic neutrino flux extending up to PeV energies raises the question of which astrophysical sources generate this signal. Blazars are one class of extragalactic sources which may produce such high-energy neutrinos. We present a likelihood analysis searching for cumulative neutrino emission from blazars in the 2nd Fermi -LAT AGN catalog (2LAC) using IceCube neutrino data set 2009-12, which was optimized for the detection of individual sources. In contrast to those in previous searches with IceCube, the populations investigated contain up to hundreds of sources, the largest one being the entire blazar sample in the 2LAC catalog. No significant excess is observed, and upper limits for the cumulative flux from these populations are obtained. These constrain the maximum contribution of 2LAC blazars to the observed astrophysical neutrino flux to 27% or less between around 10 TeV and 2 PeV, assuming the equipartition of flavors on Earth and a single power-law spectrum with a spectral index of −2.5. We can still exclude the fact that 2LAC blazars (and their subpopulations) emit more than 50% of the observed neutrinos up to a spectral index as hard as −2.2 in the same energy range. Our result takes into account the fact that the neutrino source count distribution is unknown, and it does not assume strict proportionality of the neutrino flux to the measured 2LAC γ -ray signal for each source. Additionally, we constrain recent models for neutrino emission by blazars.

METHODICAL APPROACHES TO THE CREATION MOOC (EXPERIENCE LAC

Directory of Open Access Journals (Sweden)

Larysa Nozdrina

2016-03-01

Full Text Available The article presents a number of problems, determining the current state of development of the domestic market of massive open online courses (MOOC. Considering the aim of the research, there is described national experience in this area, proposed and substantiated a number of the criteria and methodological approaches to the implementation of MOOC in higher education. The development of MOOC in the Lviv Academy of Commerce (LAC is reviewed as example. The main factors which determine the success of this educational innovation in the domestic market and are put under the research are software platforms, multimedia software for creating video lectures, course structure and support the learning process. The results of study which have been analyzed in this course can have a positive impact on the functioning of the market MOOC in Ukrainian universities. The article focuses on finding the ways of improving the process of developing and implementing MOOC in higher education in the example of LAC where Web-center on the MOODLE platform is used for e-learning. Further research should focus on the development of institutional mechanisms to ensure the effective design, implementation and operation of the MOOC in the universities in Ukraine. Particular attention during learning in massive open online course should be aimed at improving the educational process and to strengthen student's motivation in MOOC. Experience of MOOC's development in LAC can be useful at creating similar courses at other institutions of higher education in the different platforms, both MOODLE, and on the others

Biochemical studies of amylase, lipase and protease in Callosobruchus maculatus (Coleoptera: Chrysomelidae) populations fed with Vigna unguiculata grain cultivated with diazotrophic bacteria strains.

Science.gov (United States)

Silva, L B; Torres, É B; Nóbrega, R A S; Lopes, G N; Vogado, R F; Pavan, B E; Fernandes-Junior, P I

2017-12-01

The objective of this study was to evaluate the enzymatic activity of homogenates of insects fed on grain of cowpea, Vigna unguiculata (L.), cultivars grown with different nitrogen sources. For the experiment we used aliquots of the homogenate of 100 unsexed adult insects, emerged from 10 g of grain obtained from four cowpea cultivars: 'BRS Acauã', 'BRS Carijó', 'BRS Pujante', and 'BRS Tapaihum' grown under different regimes of nitrogen sources: mineral fertilizer, inoculation with strains of diazotrophs (BR 3267, BR 3262, BR 3299; INPA 03-11B, 03-84 UFLA, as well as the control (with soil nitrogen). The parameters evaluated were enzymatic activities of insect protease, amylase and lipase and the starch content of the grains. There were differences in the enzymatic activity of amylase, lipase and protease of insect homogenate according to the food source. A lower activity of the enzyme amylase from C. maculatus homogenate was observed when insects were fed grain of the cultivar BRS Carijó. A lower activity of lipase enzyme from C. maculatus homogenate was observed when the insects fed on grain from the interaction of the cultivar Tapaihum inoculated with BR 3262 diazotrophs. The lowest proteolytic activity was observed in homogenate of insects fed on interaction of 'BRS Carijó' inoculated with BR 3262 diazotrophs. Starch content correlated positively with the amylase activity of C. maculatus homogenate. The cultivar BRS Carijó had a different behavior from the other cultivars, according to the cluster analysis.

Essential oil optimizes the susceptibility of Callosobruchus maculatus and enhances the nutritional qualities of stored cowpea Vigna unguiculata.

Science.gov (United States)

Akami, Mazarin; Chakira, Hamada; Andongma, Awawing A; Khaeso, Kanjana; Gbaye, Olajire A; Nicolas, Njintang Y; Nukenine, E-N; Niu, Chang-Ying

2017-08-01

The intensive use of synthetic pesticides in cowpea storage has led to the development of resistance by Callosobruchus maculatus and subsequent degradation of grain quality. In an attempt to circumvent these constraints, the susceptibility of C. maculatus to 2,2-dichlorovinyldimethyl phosphate (DDVP) and Lippia adoensis essential oil (EO) was investigated and variations in the proportions of nutritional values of treated grains 150 days after storage were assessed. The survival rate was recorded after five generations. The resistance index and biochemical parameters of grains were determined. The results from this study revealed that the survival rate and resistance index significantly increased proportionally with damage in DDVP treatments ( r  = 0.889; p  = 0.018) while in EO treatments, those values remained low without significant variations ( p  = 0.0764) throughout the generations. DDVP stored grains yielded higher crude protein values, but lower carbohydrates, tannins, phenolics and minerals compared to EO. Eighteen amino acids were detected in EO treated grains and 14 in DDVP which was devoid of albumin and prolamin. Lippia adoensis EO could therefore represent a safe alternative bio-pesticide to cope with insect resistance and enhance the nutritional qualities of stored cowpea seeds.

A geological survey of the Lac du Bonnet batholith, Manitoba

International Nuclear Information System (INIS)

McCrank, G.F.D.

1985-02-01

This report presents the results of a geological survey of the Lac du Bonnet batholith in Manitoba. The survey consisted of field mapping of the lithologies and the joint systems throughout the batholith, and the examination of lineaments identified on aerial photographs and Landsat imagery. Petrographic descriptions and a map of the lithologies, an analysis of the fracture systems and a lineament map are presented. The results of various regional geophysical surveys were used as an aid to the interpretation of the batholith's contacts and in the interpretation of lineaments as possible faults. A comparison of the Lac du Bonnet Batholith with the Eye-Dashwa Lakes Pluton near Atikokan, Ontario is also presented

Inherited influence of low dose gamma radiation on the reproductive potential and spermiogenesis of the cowpea weevil, Callosobruchus maculatus (F (Coleoptera: Chrysomelidae

Directory of Open Access Journals (Sweden)

Hatem A. Ibrahim

2017-10-01

Full Text Available The southern cowpea weevil, Callosobruchus maculatus (F is a severe agriculture pest worldwide. In the current work, newly emerged adult males of C. maculatus have been irradiated with a low dose of 20Gy gamma radiation. The inherited deleterious effects on the fecundity, hatchability, adult emergence, and the sterility percent were recorded for the progenies F1 and F2 of the irradiated parental males. The fecundity, hatched larvae, the number of males and females were reduced in both F1 and F2. The sterility percent was high in F1 (70.8% and increased in the F2 (88.3% generation. Histopathological effects were also documented in the testes of F1 and F2 progenies. The spermatids and sperms have exhibited a variety of abnormalities. In the early spermatids, the nebenkern outer cell membrane was ruptured. The spermatid nucleus loses its homogeneous texture and has multiple foci of dense chromatin, as well as, profiles range has little dense material. In some groups, the nucleus had a peculiar ring of chromatin. The sperms had shown a variety of aberrations. The sperms irregularity distributed in lysed cysts by unusual manner. Also, some sperms had remarkably enlarged axoneme and small rounded nucleus. Many of the sperm cells were observed with two axonemes, abnormal mitochondria derivatives, and more than two accessory bodies. These results indicate that the low dose of 20 Gy induces semi-sterility in C. maculatus through generations. The same technique would help to improve using of sterile insect technique for other agriculture pests.

Competitiveness values of irradiated adults of callosobruchus maculatus (F.) irradiated as mature pupae

International Nuclear Information System (INIS)

Ahmed, M.Y.Y.

1981-01-01

When mature pupae of Callosobruchus maculatus were treated with 3 Krad, the resulting adults were sterile when they were paired with untreated opposite sex. Males and females both treated with a sterilizing dose (3 Krad) and confined with untreated (U) males and females at a I male: I female: U male: U female (irradiated males: irradiated females: unirradiated males: unirradiated females) ratio caused 69.1% infertility in the resulting eggs. When the ratio of sterile males and females was increased to 5.5:1:1; 10:10:1:1 or 15:1:1 (I male: female: U male: U female) the percentage infertility reached 82.5, 95.0 and 100.0, respectively. The percentage of observed infertility was less than the expected infertility for the ratios 1:1:1:1:5:5:1:1 and 10:10:1:1, but it was exceeded with the highest ratio used (15:15:1:1). Competitiveness values for irradiated adults increased with an increasing ratio of irradiated to unirradiated adults. Since the ratio of 15:15:1:1 gave rise to 100% egg infertility (the expected infertility was 99.6%), no F 1 adults was produced; and the competitiveness value slightly exceeded 1.0 (i.e. the sterile adults were fully competitive with the normal ones). These results indicated that irradiation with 3 Krad, a sterilizing dose, did not decrease sexual competitiveness of irradiated adults. Also, the release of (I) females together with (I) males could give good results in controlling a population of C. maculatus in a autocidal control program; and, therefore, separation of the sexes prior to release is probably unnecessary. (author)

Negative Assortative Mating Based on Body Coloration in the Freshwater Platyfish (Poecillidae: Xiphophorus maculatus

Directory of Open Access Journals (Sweden)

Tyler E. Frankel

2017-04-01

Full Text Available The ability of individuals within a population to survive and thrive is highly dependent upon the maintenance of genetic variation and phenotypic diversity, thereby ensuring adaptation to dynamic environments. A fundamental method of maintaining such variation is through a negative assortative mating strategy, in which individuals would be expected to reproductively select members of the opposite sex that exhibit dissimilar phenotypes. Employing three uniform body color morphs, red, yellow and blue, of the platyfish (Xiphophorus maculatus, this study was designed to investigate whether X. maculatus females would preferentially be attracted to males exhibiting an alternative color, thereby enabling an examination of the effect of male body coloration on mate choice by adult females. Mate choice was determined based on the initial preference of each female, as well as the amount of time females spent associating with each male. Initial preferences were analyzed using a binomial distribution test, and overall preference data using Wilcoxon signed rank tests. Red females initially selected for dissimilar colored males, and spent a significantly larger amount of time associating with blue and yellow males, as did yellow females with red and blue males. Blue females initially selected and spent a significantly larger amount of time associating with red males but, interestingly, showed no selective preference between blue and yellow males. In these experimental trials, the overall strong mate selection exhibited by female platyfish for males of dissimilar coloration is suggestive of a negative assortative mating strategy and provides evidence for the maintenance of color polymorphism in nature populations.

Toxicity of Buprofezin on the Survival of Embryo and Larvae of African Catfish, Clarias gariepinus (Bloch)

OpenAIRE

Marimuthu, Kasi; Muthu, Narmataa; Xavier, Rathinam; Arockiaraj, Jesu; Rahman, M. Aminur; Subramaniam, Sreeramanan

2013-01-01

Buprofezin is an insect growth regulator and widely used insecticide in Malaysia. The present study evaluated the toxic effects of buprofezin on the embryo and larvae of African catfish (Clarias gariepinus) as a model organism. The embryos and larvae were exposed to 7 different concentrations (0, 0.05, 0.5, 5, 25, 50 and 100 mg/L) of buprofezin. Each concentration was assessed in five replicates. Eggs were artificially fertilized and 200 eggs and larvae were subjected to a static bath treatme...

Oxygen Consumption and Acoustic Activity of Adult Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae) during Hermetic Storage.

Science.gov (United States)

Njoroge, Anastasia W; Mankin, Richard W; Smith, Bradley W; Baributsa, Dieudonne

2018-04-20

Acoustic monitoring was applied to consider hermetic exposure durations and oxygen levels required to stop adult Callosobruchus maculatus activity and economic damage on cowpea. A 15-d study was conducted with six treatments of 25, 50, and 100 C. maculatus adults in 500 and 1000 mL jars using acoustic probes inserted through stoppers sealing the jars. Acoustic activity as a result of locomotion, mating, and egg-laying was measured by identifying sound impulses with frequency spectra representative of known insect sounds, and counting trains (bursts) of impulses separated by intervals of <200 ms, that typically are produced only by insects. By the end of the first week of storage in all treatments, oxygen levels declined to levels below 4%, which has been demonstrated to cause mortality in previous studies. Concomitantly, insect sound burst rates dropped below an acoustic detection threshold of 0.02 bursts s −1 , indicating that the insects had ceased feeding. Statistically significant relationships were obtained between two different measures of the acoustic activity and the residual oxygen level. Based on the experimental results, a simple equation can be used to estimate the time needed for oxygen to decline to levels that limit insect feeding damage and thus grain losses in hermetic storage containers of different insect population levels and various volumes.

Exposure to 4100K fluorescent light elicits sex specific transcriptional responses in Xiphophorus maculatus skin.

Science.gov (United States)

Boswell, William T; Boswell, Mikki; Walter, Dylan J; Navarro, Kaela L; Chang, Jordan; Lu, Yuan; Savage, Markita G; Shen, Jianjun; Walter, Ronald B

2018-06-01

It has been reported that exposure to artificial light may affect oxygen intake, heart rate, absorption of vitamins and minerals, and behavioral responses in humans. We have reported specific gene expression responses in the skin of Xiphophorus fish after exposure to ultraviolet light (UV), as well as, both broad spectrum and narrow waveband visible light. In regard to fluorescent light (FL), we have shown that male X. maculatus exposed to 4100K FL (i.e. "cool white") rapidly suppress transcription of many genes involved with DNA replication and repair, chromosomal segregation, and cell cycle progression in skin. We have also detailed sex specific transcriptional responses of Xiphophorus skin after exposure to UVB. However, investigation of gender differences in global gene expression response after exposure to 4100K FL has not been reported, despite common use of this FL source for residential, commercial, and animal facility illumination. Here, we compare RNA-Seq results analyzed to assess changes in the global transcription profiles of female and male X. maculatus skin in response to 4100K FL exposure. Our results suggest 4100K FL exposure incites a sex-biased genetic response including up-modulation of inflammation in females and down modulation of DNA repair/replication in males. In addition, we identify clusters of genes that become oppositely modulated in males and females after FL exposure that are principally involved in cell death and cell proliferation. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of gamma radiation on the metamorphic stages of Dermestes maculatus DeGeer (Coleoptera: Dermestidae)

International Nuclear Information System (INIS)

Seal, D.R.; Tilton, E.W.

1986-01-01

The effects of γ-radiation on all stages of the hide beetle Dermestes maculatus, DeGeer were studied. Eggs of D. maculatus were more susceptible to γ radiation than other stages. Egg radiosensitivity decreased with increasing embryonic development. An absorbed dose of 200 Gy killed the 1st, 6th and 7th instar larvae, but the 4th and 5th instar larvae were more resistant. The developmental period increased in treated larvae. Pupae (24 h) treated with 150 Gy failed to eclose, but eclosion was not affected in older pupae. Adults from female pupae irradiated at 72 h with 150 Gy were infertile, but male pupae required more than 200 Gy for sterilization. The average number of eggs per female decreased with increasing doses when either the male or female of the pair was irradiated as pupae or adults. Adult males were sterile after irradiation 300 Gy and adult females treated with the same dose failed to lay eggs. Newly emerged irradiated adults or female adults from irradiated 72-h-old pupae recovered some fertility after treatment with doses as high as 150 Gy. Adult males from irradiated 72-h-old pupae were treated at doses of 50 and 100 Gy showed a higher reproductive capacity at 60 days than at 15 days post-treatment. A dose between 200 and 300 Gy was necessary to provide complete sterility of 24-h-old adults. (author)

CLUSTERING OF γ-RAY-SELECTED 2LAC FERMI BLAZARS

Energy Technology Data Exchange (ETDEWEB)

Allevato, V.; Finoguenov, A. [Department of Physics, University of Helsinki, Gustaf Hällströmin katu 2a, FI-00014 Helsinki (Finland); Cappelluti, N. [University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States)

2014-12-20

We present the first measurement of the projected correlation function of 485 γ-ray-selected blazars, divided into 175 BL Lacertae (BL Lacs) and 310 flat-spectrum radio quasars (FSRQs) detected in the 2 year all-sky survey by the Fermi-Large Area Telescope. We find that Fermi BL Lacs and FSRQs reside in massive dark matter halos (DMHs) with log M{sub h} = 13.35{sub −0.14}{sup +0.20} and log M{sub h} = 13.40{sub −0.19}{sup +0.15} h {sup –1} M {sub ☉}, respectively, at low (z ∼ 0.4) and high (z ∼ 1.2) redshift. In terms of clustering properties, these results suggest that BL Lacs and FSRQs are similar objects residing in the same dense environment typical of galaxy groups, despite their different spectral energy distributions, power, and accretion rates. We find no difference in the typical bias and hosting halo mass between Fermi blazars and radio-loud active galactic nuclei (AGNs), supporting the unification scheme simply equating radio-loud objects with misaligned blazar counterparts. This similarity in terms of the typical environment they preferentially live in, suggests that blazars tend to occupy the center of DMHs, as already pointed out for radio-loud AGNs. This implies, in light of several projects looking for the γ-ray emission from DM annihilation in galaxy clusters, a strong contamination from blazars to the expected signal from DM annihilation.

Efeitos de extratos alcoólicos de plantas sobre o caruncho do feijão vigna (Callosobruchus maculatus Effect of alcoholic extract of plants on weevil of cowpea (Callosobruchus maculatus

Directory of Open Access Journals (Sweden)

Francisco de A. C. Almeida

2005-12-01

Full Text Available Através de três métodos, extratos vegetais foram aplicados, ao Callosobruchus maculatus na fase adulta, inoculados ou não em uma massa de sementes, e na fase imatura (ovo com o objetivo de se controlar esta praga do feijão armazenado. Utilizaram-se flores, folhas, frutos e caule secos de oito espécies vegetais na obtenção dos extratos, em percolador, com solvente álcool etílico (70%. O delineamento experimental utilizado foi o inteiramente ao acaso, com os tratamentos distribuídos em esquema fatorial, cujos fatores quantitativos foram revelados pela regressão na análise de variância. Mediante os resultados obtidos, concluiu-se que a mortalidade dos insetos está relacionada com o tipo de extrato, os métodos de aplicação e com a dosagem aplicada, sendo os extratos de Callopogonium caeruleum e Piper nigrum os mais eficientes no controle do caruncho de feijão.Vegetable extracts were applied, through three methods, to the Callosobruchus maculatus in the adult phase, inoculated or not in a mass of seeds, in the immature phase (egg with the objective of controlling this pest of the stored beans. Dry flowers, leaves, fruits and dry stems of eight vegetable species were used to obtain the extracts in an extractor, with ethyl alcohol (70%. A completely randomized statistical design was used with the treatments distributed in a factorial scheme, the quantitative factors were analysed by the regression in the variance analysis. From the results obtained, it was concluded that the mortality of the insects is related to the extract type, the application methods and the applied dose, being the extracts of Callopogonium caeruleum and Piper nigrum the most efficient in the control of the weevil of cowpea.

Louisiana SIP: LAC 33:III Ch 21 Subchap J, 2147--Limiting Volatile Organic Compound (VOC) Emissions from Reactor Processes and Distillation Operations in Synthetic Organic Chemical manufacturing Industry (SOCMI); SIP effective 1998-02-02 (LAc74) to more..

Science.gov (United States)

Louisiana SIP: LAC 33:III Ch 21 Subchap J, 2147--Limiting Volatile Organic Compound (VOC) Emissions from Reactor Processes and Distillation Operations in Synthetic Organic Chemical manufacturing Industry (SOCMI); SIP effective 1998-02-02 (LAc74) more...

The BL Lac objects PKS 1144-379

International Nuclear Information System (INIS)

Nicolson, G.D.; Glass, I.S.; Feast, M.W.; Andrews, P.J.

1979-01-01

The highly variable radio source PKS 1144-379 has been monitored at 13 cm and 6 cm over a period of 3 years. It has been identified with an object whose photographic image is star-like. From infrared photometry, UBVRsub(KC)Isub(KC) photometry and spectroscopy, it is concluded that PKS 1144-379 is a BL Lac object with msub(v) approximately = 16.2. (author)

Histopathological Effects of Gammalin 20 on African Catfish (Clarias gariepinus)

International Nuclear Information System (INIS)

Ezemonye, L.; Ogbomida, T.E.

2010-01-01

Clarias gariepinus fingerlings exposed to lethal and sublethal concentrations of Gammalin 20 were investigated in a renewal static bioassay with particular reference to behaviour, survival, and histopathological changes. Early symptoms of gammalin 20 lethal poisoning were, respiratory distress, increased physical activity, convulsions, erratic swimming, loss of equilibrium, and increased breathing activity. Behavioural response was dose dependent and decreased with decreased concentration. The 96-hour lethal concentration (LC 50 ) value was 30 ppb. Histopathological changes of the gill, liver, and intestinal tissues of fish treated with sublethal concentration of gammalin 20 for twelve weeks showed gill distortion and fusion of adjacent secondary lamella as a result of hyperplasia and excessive mucus accumulation. The liver showed swelling of hepatocytes with mild necrosis, pyknosis, and vacuolation, while the intestine showed yellow bodies of the lamina propria at the tip of the mucosal fold. environmental monitoring hazardous substances like heavy metals, pesticides

Microbial evaluation and occurrence of antidrug multi-resistant organisms among the indigenous Clarias species in River Oluwa, Nigeria

Directory of Open Access Journals (Sweden)

T.A. Ayandiran

2017-01-01

Full Text Available Fish may harbor pathogens on or inside its body when in contaminated environment. Clarias gariepinus and Clarias buthopogon were analyzed to evaluate the likely impact of pollution on the antidrug resistance pattern of their microbial isolates. Different bacterial and fungal counts were observed on the fish organs (skin, muscles and gills. The highest bacterial count was 1,040,000 Cfu/mL while the lowest was 101 Cfu/mL. The highest fungal count obtained was 344,000 Cfu/mL while the lowest was 65 Cfu/mL. Bacterial isolates belonging to genera Bacillus, Clostridium, Alcaligenes, Flavobacterium, Enterobacter and Corynebacterium were obtained from the organs. Also, fungal isolates belonging to the genera Penicillium, Aspergillus, Rhizopus, Monila and Fusarium were isolated. The resistance of isolates from C. gariepinus to drugs was between 50% and 90% with Bacillus species showing the highest resistance. For isolates from C. buthopogon, 40–90% resistance was observed with Alcaligenes faecalis showing highest resistance. Five patterns of multiple drug resistance were observed among the bacterial isolates with antibiotics ranging from 4 to 9. Also, result of fungal isolates showed susceptibility to ketoconazole and resistant to fluconazole and griseofulvin. The public health implications of consuming these fishes are discussed.

Gtl2lacZ, an insertional mutation on mouse chromosome 12 with parental origin-dependent phenotype.

Science.gov (United States)

Schuster-Gossler, K; Simon-Chazottes, D; Guenet, J L; Zachgo, J; Gossler, A

1996-01-01

We have produced a transgenic mouse line, Gtl2lacZ (Gene trap locus 2), that carries an insertional mutation with a dominant modified pattern of inheritance:heterozygous Gtl2lacZ mice that inherited the transgene from the father show a proportionate dwarfism phenotype, whereas the penetrance and expressivity of the phenotype is strongly reduced in Gtl2lacZ mice that inherited the transgene from the mother. On a mixed genetic background this pattern of inheritance was reversible upon transmission of the transgene through the germ line of the opposite sex. On a predominantly 129/Sv genetic background, however, transgene passage through the female germ line modified the transgene effect, such that the penetrance of the mutation was drastically reduced and the phenotype was no longer obvious after subsequent male germ line transmission. Expression of the transgene, however, was neither affected by genetic background nor by parental legacy. Gtl2lacZ maps to mouse Chromosome 12 in a region that displays imprinting effects associated with maternal and paternal disomy. Our results suggest that the transgene insertion in Gtl2lacZ mice affects an endogenous gene(s) required for fetal and postnatal growth and that this gene(s) is predominantly paternally expressed.

Monoclonal antibody to serum immunoglobulins of Clarias batrachus and its application in immunoassays.

Science.gov (United States)

Sood, Neeraj; Chaudhary, Dharmendra K; Singh, Akhilesh; Rathore, Gaurav

2012-12-15

Serum immunoglobulins of Clarias batrachus (Cb-Ig) were purified by affinity chromatography using bovine serum albumin as capture ligand. Under reducing conditions in SDS-PAGE, Cb-Ig was composed of a heavy (H) chain (68.7 kDa) and two light (L) chains (27.4 and 26.3 kDa). Purified Cb-Ig was used to produce a monoclonal antibody (MAb) designated E4 MAb that belonged to IgG1 subclass. In Western blotting, this MAb showed binding to H chain of purified Cb-Ig and putative H chains in reduced sera of C. batrachus, Clarias gariepinus and Heteropneustes fossilis. However, no binding was observed with serum protein of Labeo rohita and Channa striata. Cross-reactivity of anti-Cb-Ig MAb was observed with serum of C. batrachus, C. gariepinus and H. fossilis in competitive ELISA. In immunoblotting of non-reduced Cb-Ig with E4 MAb, four bands assumed to be tetrameric, trimeric, dimeric and monomeric form were observed. In flow cytometric analysis of the gated lymphocytes, the number of surface Ig-positive (Ig+) cells in blood, spleen, kidney and thymus of C. batrachus was determined to be 50.1 ± 3.1, 55.1 ± 3.36, 42.4 ± 4.81 and 5.1 ± 0.89%, respectively, using E4 MAb. Ig+ cells were also demonstrated in formalin-fixed paraffin embedded tissue sections of spleen, kidney, thymus and smears of blood mononuclear cells in indirect immunoperoxidase test. The developed MAb was employed to detect pathogen-specific immunoglobulins in the sera of C. batrachus immunized with killed Edwardsiella tarda, by an indirect ELISA. This monoclonal antibody can be useful tool in immunological research and assays. Copyright © 2012 Elsevier B.V. All rights reserved.

African catfish Clarias gariepinus farming practices in North and South 24 Parganas districts of West Bengal, India

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Thangapalam Jawahar Abraham

2018-04-01

Full Text Available Clarias gariepinus is widely cultured due to its tolerance to environmental extremes, high production and good feed conversion rate. This communication describes the farming practices of C. gariepinus in North and South 24 Parganas districts of West Bengal. Clarias gariepinus is cultured in ponds of 0.1–0.75 ha, where fingerlings were stocked at a density of 860–1150 cubic meter–1. The current practices of seed transportation were stressful to fish as the majority of the farmers noticed 5–10% mortalities, despite the use of antibiotics. Acclimatization of seeds was practiced by the majority of farmers before stocking. Different feeds including slaughter-house wastes and dead poultry were supplied. Multiple stocking and harvesting were a common practice. Major problems identified were insufficient feed, disease, transport, poor seed quality and lack of financial support. The survival percentage was poor, as 88% of the farmers recorded <40–50% survival at harvest. Dropsy was the most common disease and had a significant impact on economy. Antibiotics or other aquadrugs were frequently used for treatment, although the success varied. In general, the C. gariepinus farming has helped to recycle the wastes generated in and around metropolitan Kolkata and adjacent municipalities into wealth, but it suffers from management issues and huge economic losses. This calls for immediate attention from researchers, administrators and extension personals.

Estabilidade da resistência de genótipos de caupi a Callosobruchus maculatus (Fabr. em gerações sucessivas

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Lima Marcileyne Pessôa Leite de

2002-01-01

Full Text Available Callosobruchus maculatus (Fabr. (Coleoptera: Bruchidae é a principal praga do caupi (Vigna unguiculata L. armazenado em condições tropicais e subtropicais. Avaliaram-se a estabilidade da resistência e a capacidade de adaptação de C. maculatus a genótipos de caupi, durante seis gerações. Utilizou-se o teste sem chance de escolha, em delineamento experimental inteiramente casualizado, em esquema fatorial, com dez tratamentos, seis gerações do inseto e cinco repetições. Cada repetição constou de 30 grãos infestados com dois casais da praga. O número de ovos/fêmea diferiu entre os genótipos de caupi apenas na sexta geração, e entre as gerações em BR14-Mulato, Bico de Pato, TE90-180-3E e TE87-98-8G. A viabilidade de ovos diferiu entre as gerações em BR17-Gurguéia, BR14-Mulato, IT89KD-260 e IT89KD-245, e entre os genótipos nas terceira, quinta e sexta gerações. Os genótipos diferiram entre e dentro das gerações, em relação à duração e a viabilidade da fase imatura. Observou-se redução na emergência, especialmente em IT89KD-245, IT89KD-260, CNC 0434, Bico de Pato, TE90-180-10F e BR14-Mulato, provavelmente devido a substâncias químicas presentes nos grãos que afetaram a sobrevivência dos insetos, ao longo das gerações. Os genótipos IT89KD-245 e IT89KD-260 comportaram-se como moderadamente resistentes. Não se observou adaptação de C. maculatus aos genótipos, mantendo-se a resistência estável através das gerações.

Effects of exercise on l-carnitine and lipid metabolism in African catfish (Clarias gariepinus) fed different dietary l-carnitine and lipid levels

NARCIS (Netherlands)

Ozorio, R.O.A.; Ginneken, van V.J.T.; Bessa, R.J.B.; Verstegen, M.W.A.; Verreth, J.A.J.; Huisman, E.A.

2010-01-01

African catfish (Clarias gariepinus) were fed four isonitrogenous diets (34 % crude protein), each containing one of two lipid (100 or 180 g/kg) and two l-carnitine (15 or 1000 mg/kg) levels. After 81 d of feeding, thirty-two fish (body weight 32 g) from each dietary group were randomly selected,

Isoenergetic Replacement of Fat by Starch in Diets for African Catfish (Clarias gariepinus): Effect on Water Fluxes in the Gastro Intestinal Tract

NARCIS (Netherlands)

Harter, T.S.; Verreth, J.A.J.; Heinsbroek, L.T.N.; Schrama, J.W.

2013-01-01

The effect of an isoenergetic replacement of dietary fat by starch, on chyme characteristics and water fluxes in the gastro intestinal tract (GIT) was assessed. Adult African catfish (Clarias gariepinus) were fed a starch (SD) or fat (FD) diet and groups of fish were dissected at 2, 5 and 8 h after

High-level expression of Bacillus naganoensis pullulanase from recombinant Escherichia coli with auto-induction: effect of lac operator.

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Yao Nie

Full Text Available Pullulanase plays an important role in specific hydrolysis of branch points in amylopectin and is generally employed as an important enzyme in starch-processing industry. So far, however, the production level of pullulanase is still somewhat low from wide-type strains and even heterologous expression systems. Here the gene encoding Bacillus naganoensis pullulanase was amplified and cloned. For expression of the protein, two recombinant systems, Escherichia coli BL21(DE3/pET-20b(+-pul and E. coli BL21(DE3/pET-22b(+-pul, were constructed, both bearing T7 promoter and signal peptide sequence, but different in the existance of lac operator and lacI gene encoding lac repressor. Recombinant pullulanase was initially expressed with the activity of up to 14 U/mL by E. coli BL21(DE3/pET-20b(+-pul with IPTG induction in LB medium, but its expression level reduced continually with the extension of cryopreservation time and basal expression was observed. However, E. coli BL21(DE3/pET-22b(+-pul , involving lac operator downstream of T7 promoter to regulate foreign gene transcription, exhibited pullulanase activity consistently without detected basal expression. By investigating the effect of lac operator, basal expression of foreign protein was found to cause expression instability and negative effect on production of target protein. Thus double-repression strategy was proposed that lac operators in both chromosome and plasmid were bound with lac repressor to repress T7 RNA polymerase synthesis and target protein expression before induction. Consequently, the total activity of pullulanase was remarkably increased to 580 U/mL with auto-induction by lac operator-involved E. coli BL21(DE3/pET-22b(+-pul. When adding 0.6% glycine in culture, the extracellular production of pullulanase was significantly improved with the extracellular activity of 502 U/mL, which is a relatively higher level achieved to date for extracellular production of pullulanase. The

Comparaison de quelques caractéristiques biologiques entre Dinarmus basalis Rond. (Hymenoptera: Pteromalidae élevé soit sur son hôte habituel Callosobruchus maculatus F. (Coleoptera: Bruchidae soit sur Acanthoscelides macrophthalmus Schaef. ou Bruchidius lineatopygus Pic. identifiés comme hôtes de substitution

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Nuto, Y.

2006-01-01

Full Text Available Comparison of some Biological Characteristics between Dinarmus basalis Rond. (Hymenoptera: Pteromalidae Reared either on his Habitual Host Callosobruchus maculatus F. (Coleoptera: Bruchidae or on Acanthoscelides macrophthalmus Schaef. and Bruchidius lineatopygus Pic. Identified as Substitution Hosts. In this study, we have measured some biological parameters of Dinarmus basalis Rond. (Hymenoptera: Pteromalidae when this parasitoid grows on three hosts: Callosobruchus maculatus F. (usual host, Acanthoscelides macrophthalma Schaef. and Bruchidius lineatopygus Pic. (substitution hosts. The results of this comparative study in no choice situation show that, life duration and development duration of this parasitoid are identical in laboratory conditions. By contrast, the female fecundity, the sexual rate and the parasitism rate of D. basalis are different according to the hosts presented. Although such differences appear to be small between C. maculatus and A. macrophthalmus. In presence of these two species, the number of eggs laid by the female of D. basalis is respectively 61 ± 5.24 and 54 ± 5.60, the sexual rate 37.63 ± 2.13% and 41.73 ± 3.69% and the parasitism rate 85.46 ± 2.61% and 76.48 ± 5.90%. This indicates that these two Bruchids can be used as hosts to D. basalis for a mass production. In presence of B. lineatopygus, the fecundity and the parasitism rate of D. basalis female are very low and the sexual rate more favourable of the males. This situation is unfavourable for a parasitoid production. When D. basalis females are placed in choice situation with equal number of the hosts nowely C. maculatus and A. macrophthalmus, the parasitism rate obtained, is higher for C. maculatus that of A. macrophthalmus. This parasitism rate remains high for C. maculatus even when the other host A. macrophthalmus is twice the number of C. maculatus. Thus the parasitoid seems to have a preference for his natural host. However, A. macrophthalmus can

Effect of Gamma Radiation on Morphology and Histology of Sex Pheromone Gland of Callosobruchus maculatus (F.) Female

International Nuclear Information System (INIS)

El-Degwi, M.S.; Salem, H.M.; El-Maasarawy, S.A.S.; Ismail, I.I.

2008-01-01

The pheromone gland in normal adult female of C. maculatus consists of an internal lobe composed of glandular epithelia cells, connected dorsally with the abdominal tip. It has many tubule opening dorsally in large sets which have a groove. The size of pheromone gland of 4-day old females increased than 2-day old females. There is no difference between the gland size of 6-day old females and 4-day ones, but it decreased in females of 8-day old. In this age the gland divided into two separate parts. When females 4-day old irradiated with 100 Gy the glandular cells were separated and the nuclei were not clear. The fat bodies were less in numbers than in unirradiated ones and the glandular cell membrane is irregular. After increasing the radiation dose to 200 Gy, the glandular cells destroyed and become undistinguished. All the tubule were closed. The glandular cells in the irradiated 6-day old females with 100 Gy were compact. The nuclei and cytoplasm are very difficult to distinguished, the cytoplasm is deteriorated. As increasing the irradiation dose to 200 Gy, the glandular tissue completely damaged and appeared as narrow ribbon. Scanning electron micrographs of the abdominal tip of C.maculatus showed that the sex pheromone releasing area contains a mammiform, also it has a large number of large setae which has groove

Lac repressor: Crystallization of intact tetramer and its complexes with inducer and operator DNA

International Nuclear Information System (INIS)

Pace, H.C.; Lu, P.; Lewis, M.

1990-01-01

The intact lac repressor tetramer, which regulates expression of the lac operon in Escherichia coli, has been crystallized in the native form, with an inducer, and in a ternary complex with operator DNA and an anti-inducer. The crystals without DNA diffract to better than 3.5 angstrom. They belong to the monoclinic space group C2 and have cell dimensions a = 164.7 angstrom, b = 75.6 angstrom, and c = 161.2 angstrom, with α = γ = 90 degree and β = 125.5 degree. Cocrystals have been obtained with a number of different lac operator-related DNA fragments. The complex with a blunt-ended 16-base-pair strand yielded tetragonal bipyramids that diffract to 6.5 angstrom. These protein-DNA cocrystals crack upon exposure to the gratuitous inducer isopropyl β-D-thiogalactoside, suggesting a conformational change in the repressor-operator complex

Variabilité journalière de la qualité physico-chimique du lac M'koa ...

African Journals Online (AJOL)

d'enrichissement en matières organique, azote et phosphore capables d'influer sur la teneur de saturation en oxygène dissous. La Figure 4 montre des lavandiers communément appelés "fanico" exerçant leur activité quotidienne au lac. Cette activité est source d'enrichissement des eaux du lac. M'koa en phosphore et ...

The mimetic repertoire of the spotted bowerbird Ptilonorhynchus maculatus

Science.gov (United States)

Kelley, Laura A.; Healy, Susan D.

2011-06-01

Although vocal mimicry in songbirds is well documented, little is known about the function of such mimicry. One possibility is that the mimic produces the vocalisations of predatory or aggressive species to deter potential predators or competitors. Alternatively, these sounds may be learned in error as a result of their acoustic properties such as structural simplicity. We determined the mimetic repertoires of a population of male spotted bowerbirds Ptilonorhynchus maculatus, a species that mimics predatory and aggressive species. Although male mimetic repertoires contained an overabundance of vocalisations produced by species that were generally aggressive, there was also a marked prevalence of mimicry of sounds that are associated with alarm such as predator calls, alarm calls and mobbing calls, irrespective of whether the species being mimicked was aggressive or not. We propose that it may be the alarming context in which these sounds are first heard that may lead both to their acquisition and to their later reproduction. We suggest that enhanced learning capability during acute stress may explain vocal mimicry in many species that mimic sounds associated with alarm.

Novel Infection Site and Ecology of Cryptic Didymocystis sp. (Trematoda) in the Fish Scomberomorus maculatus.

Science.gov (United States)

Schrandt, Meagan N; Andres, Michael J; Powers, Sean P; Overstreet, Robin M

2016-06-01

An undescribed, cryptic species of Didymocystis, as determined from sequences of 2 ribosomal genes and superficially similar to Didymocystis scomberomori ( MacCallum and MacCallum, 1916 ), infected the skin of the Spanish mackerel, Scomberomorus maculatus , in the north-central Gulf of Mexico (GOM). An analysis of 558 fish from 2011 to 2013 from Louisiana, Mississippi, Alabama, and the Florida panhandle showed the prevalence of the trematode varied both spatially and temporally but not with sex of the fish host. Month, year, and geographic location were identified by a negative binomial generalized linear model as indicators of the abundance and intensity of infection. Prevalence, abundance, and intensity of infection were greatest in spring and fall months off the Florida panhandle. Furthermore, the abundance and intensity of infection correlated negatively with fork length, weight, and gonad weight of mature fish but positively with longitude. Therefore, smaller adult fish tended to be more infected than larger adults, and prevalence and intensity increased from west to east (Louisiana to Florida). Spatial and temporal trends seemed to result from physical factors (e.g., water temperature, salinity, bottom type), but they also coincided with the annual migration of S. maculatus as fish moved northward along the GOM coastline from the southern tip of Florida in the spring months and returned in the fall, being present in the north-central GOM from late spring through fall. This pattern suggests the possibility that acquisition of infections occurred from a molluscan host in waters off the Florida panhandle.

Bioaccumulation of heavy metals and parasitic fauna in Synodontis clarias (Linnaeus, 1758 and Chrysichthys nigrodigitatus (Lacepede, 1803 from Lekki Lagoon, Lagos, Nigeria

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Bamidele Akinsanya

2016-08-01

Full Text Available Objective: To study the bioaccumulation of heavy metals from Synodontis clarias (S. clarias and Chrysichthys nigrodigitatus (C. nigrodigitatus with their parasitic fauna. Methods: A total of 50 specimens of each fish species (n = 100 were examined. The fishes were subjected to parasitological investigation while 3 g of intestinal tissue of S. clarias and C. nigrodigitatus samples were digested with nitric acid (10 mL. The tissues were then heated until brown fumes disappeared. The samples were allowed to cool and distilled water was added to make up to 50 mL in a standard flask. The filtrate was examined using the atomic absorption spectrometer. The fish hosts were weighed and measured with the aid of digital weighing balance and measuring board, respectively. Results: The Chi-square distribution was significant at 0.01 level (χ2 = 2.16, P Zn > Mn > Fe > Cd (not detected and Mn > Zn > Fe > Pb > Cd (not detected, respectively, while in the nematode, Procamallanus spp. and trematode, Siphodera spp. were Pb > Mn > Fe > Zn > Cd and Mn > Fe > Zn > Pb > Cd, respectively. In the water and sediment, the distribution of heavy metals were Fe > Mn > Zn > Pb > Cd and Fe > Mn > Pb > Zn > Cd, respectively. Conclusions: The findings of the concentrations of the trace elements in the aquatic habitat as well as the sediment were below the permissible limit of Federal Ministry of Environment. These findings confirmed that the aquatic habitat was adequate for fishing activity and that the consumption of fish species therein are safe. However, it should be noted that there was bioaccumulation of trace elements in the fish tissues which should not pose any danger to man. Therefore, a regular monitoring of the levels of trace elements in the water body as well as in the fauna should be regularly undertaken.

Characterization of pLAC1, a cryptic plasmid isolated from Lactobacillus acidipiscis and comparative analysis with its related plasmids.

Science.gov (United States)

Asteri, Ioanna-Areti; Papadimitriou, Konstantinos; Boutou, Effrossyni; Anastasiou, Rania; Pot, Bruno; Vorgias, Constantinos E; Tsakalidou, Effie

2010-07-15

The pLAC1 plasmid of Lactobacillus acidipiscis ACA-DC 1533, a strain isolated from traditional Kopanisti cheese, was characterised. Nucleotide sequence analysis revealed a circular molecule of 3478bp with a G+C content of 37.2%. Ab initio annotation indicated four putative open reading frames (orfs). orf1 and orf4 were found to encode a replication initiation protein (Rep) and a mobilization protein (Mob), respectively. The deduced products of orf2 and orf3 revealed no significant homology to other known proteins. However, in silico examination of the plasmid sequence supported the existence of a novel operon that includes rep, orf2 and orf3 in pLAC1 and that this operon is highly conserved also in plasmids pLB925A02, pSMA23, pLC88 and pC7. RT-PCR experiments allowed us to verify that these three genes are co-transcribed as a single polycistronic mRNA species. Furthermore, phylogenetic analysis of pLAC1 Rep and Mob proteins demonstrated that they may have derived from different plasmid origins, suggesting that pLAC1 is a product of a modular evolution process. Comparative analysis of full length nucleotide sequences of pLAC1 and related Lactobacillus plasmids showed that pLAC1 shares a very similar replication backbone with pLB925A02, pSMA23 and pLC88. In contrast, mob of pLAC1 was almost identical with the respective gene of plasmids pLAB1000, pLB4 and pPB1. These findings lead to the conclusion that pLAC1 acquired mob probably via an ancestral recombination event. Our overall work highlights the importance of characterizing plasmids deriving from non-starter 'wild' isolates in order to better appreciate plasmid divergence and evolution of lactic acid bacteria. 2010 Elsevier B.V. All rights reserved.

A set of lacZ mutations in Escherichia coli that allow rapid detection of each of the six base substitutions

International Nuclear Information System (INIS)

Cupples, C.G.; Miller, J.H.

1989-01-01

We describe the construction of six strains of Escherichia coli with different mutations at the same coding position in the lacZ gene, which specifies the active site glutamic acid residue at position 461 in beta'-galactosidase. Each strain is Lac- and reverts to Lac+ only by restoring the glutamic acid codon. The strains have been designed so that each reverts via one of the six base substitutions. The set of strains allows detection of each transition and transversion simply by monitoring the Lac- to Lac+ frequency, as demonstrated here with characterized mutagens and mutator alleles. These strains are useful for rapidly determining the mutagenic specificity of mutagens at a single site, for detecting low levels of stimulation of certain base substitutions, for monitoring specific base changes in response to various experimental conditions or strain backgrounds, and for isolating new mutator strains

Biological effects of some plant oils, gamma radiation and their interactive effects on callosobruchus maculatus (F.)

International Nuclear Information System (INIS)

EI-Orabi, M. N.; Shafei, D.M.Y.; Amer, A.M.

2007-01-01

Garlic, lemon and castor oils were evaluated for the control of infestation of Callosobruchus maculatus (F.). Oviposition, hatch ability, adult emergence were evaluated, Egg deposition was completely inhibited when cowpea seeds were treated with garlic, lemon and castor oils at doses 80,120 and 1300μl. Mean number of eggs laid by a female was significantly reduced by subjecting all developmental stages to increased radiation doses when the targeted sex was male, female or both. Egg deposition was. completely inhibited depending, on the irradiated sex and the developmental stage

USING THE METHODS OF WAVELET ANALYSIS AND SINGULAR SPECTRUM ANALYSIS IN THE STUDY OF RADIO SOURCE BL LAC

OpenAIRE

Donskykh, G. I.; Ryabov, M. I.; Sukharev, A. I.; Aller, M.

2014-01-01

We investigated the monitoring data of extragalactic source BL Lac. This monitoring was held withUniversityofMichigan26-meter radio  telescope. To study flux density of extragalactic source BL Lac at frequencies of 14.5, 8 and 4.8 GHz, the wavelet analysis and singular spectrum analysis were used. Calculating the integral wavelet spectra allowed revealing long-term  components  (~7-8 years) and short-term components (~ 1-4 years) in BL Lac. Studying of VLBI radio maps (by the program Mojave) ...

Lactase from Clarias Gariepinus and its Application in Development of Lactose Sensor

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Sandeep K. SHARMA

2007-08-01

Full Text Available A natural source of lactase enzyme was reported for the first time from an omnivorous cat fish, Clarias gariepinus. The lactase enzyme has been partially purified from catfish intestine using FPLC. The enzyme had specific activity 6.75 units mg-1 with an overall recovery of 80%. The enzyme was characterized and kinetic properties such as Km(4.8mM,Vmax (11.66 μmoles min-1mg-1, optimum pH(7.2 – 7.5 and thermal inactivation have been studied. The enzyme was stable on storage at 4 oC with only 5% loss in enzyme activity in 120 days. The energy of activation for thermal inactivation of catfish lactase was 23 K cal mol-1. The partially purified enzyme was used for the fabrication of lactose biosensor.

The clean development mechanism (CDM) an international perspective and implications for the LAC region

International Nuclear Information System (INIS)

2004-08-01

This paper addresses activity a) an analysis of international CDM experiences and its potential contribution to the LAC region. The paper begins with a section describing the basic principles of the CDM and retrieves the lessons learned from the first two years of the CDM operation. This is followed by a more detailed review in section 2 of the on-going baseline and monitoring methodology approval process. In section 3, the development value of the CDM is explored. Section 4 describes the current CDM markets, while section 5 reviews the response of host countries to the CDM outside the LAC region. Section 6 describes the various capacity building programs established by Annex 1 countries to support the CDM. In each of the first 6 sections, implications for the LAC region are identified. Section 7 brings these conclusions together into a concise summary. (The author)

EFEKTIVITAS KOMBINASI PROBIOTIK MIKROENKAPSULASI MELALUI PAKAN UNTUK PENGENDALIAN PENYAKIT MOTILE AEROMONADS SEPTICEMIA PADA IKAN LELE, Clarias gariepinus

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Angela Mariana Lusiastuti

2017-10-01

Full Text Available Penelitian ini bertujuan untuk mengetahui efektivitas kombinasi probiotik mikroenkapsulasi melalui pakan dalam pengendalian penyakit pada ikan lele, Clarias gariepinus. Penelitian dilakukan mulai dari penyiapan kombinasi probiotik Bacillus cereus ND2 dan Staphylococcus lentus L1K, mikroenkapsulasi probiotik, uji probiotik mikroenkapsulasi, serta uji dosis secara in vivo. Proses mikroenkapsulasi menggunakan BUCHI mini spray dryer dengan suhu inlet 131°C-133°C dan suhu outlet 65°C-70°C. Pakan yang digunakan adalah pakan buatan dengan kadar protein 38% yang dicampur dengan probiotik mikroenkapsulasi sesuai dengan dosis perlakuan dan diberi putih telur 2% sebagai binder. Perlakuan yang dilakukan adalah membandingkan secara in vivo probiotik mikroenkapsulasi (PM dan probiotik non-mikroenkapsulasi (PNM, dan dilanjutkan pengujian dosis melalui pakan untuk memperoleh dosis terbaik dari aplikasi probiotik mikroenkapsulasi. Parameter pengamatan berupa tingkat sintasan, biomassa, kadar hematokrit, hemoglobin, respiratory burst activity, dan total bacterial count. Hasil penelitian menunjukkan bahwa suplementasi kombinasi probiotik mikroenkapsulasi Bacillus cereus ND2 dan Staphylococcus lentus L1K pada pakan lebih efektif, dan dengan dosis 2% menunjukkan hasil yang lebih baik dalam meningkatkan sintasan hingga 97,33%, biomassa dan respons imun (NBT assay, hematocrit, hemoglobin ikan lele terhadap A. hydrophila. This study was aimed to know the effectivity of microencapsulated probiotic combinations administered through diet to control motile aeromonads septicemia disease in catfish (Clarias gariepinus. The research stages consisted of preparation probiotics, microencapsulation of probiotics and probiotic microencapsulation testing in vivo. BUCHI mini spray dryer was used in the microencapsulation process with inlet temperature ranged between 131°C-133°C and outlet temperature ranged between 65°C-70°C. The diets used in the research were pelleted

Lipofection of rabbit chondrocytes and long lasting expression of a lacZ reporter system in alginate beads.

Science.gov (United States)

Stöve, J; Fiedler, J; Huch, K; Günther, K-P; Puhl, W; Brenner, R

2002-03-01

Our aim was to investigate the maintenance of the transfection status of non-viral transfected chondrocytes in an alginate culture system. Chondrocytes harvested from rabbit knees were isolated by sequential digestion and cultivated in monolayer culture. At 60-70% cell density, chondrocytes were transfected with different transfection systems (FuGENE6, CaCl2, Lipofectin). A lac Z expression vector (pcDNA 3.1/Myc-His+ lacZ) was used as a reporter system. In order to improve transfection rates, hyaluronidase (4 U/ml) was used prior and during the transfection procedure. Thereafter, transfected cells were either kept in monolayer culture or embedded in alginate beads and kept in culture for up to the next 30 weeks. Transfection efficiency was maximal using FuGENE6TM/DNA at a ratio of 3:2 and hyaluronidase (4 U/ml). Transfection efficiency reached up to 40.8% (+/- 3.2%) after 36 h. In alginate beads lac Z positive cells declined to 8.5% +/- 3.3% after 4 weeks and to 4.6% +/- 3.2% after 12 weeks of culturing. After 30 weeks 3% of chondrocytes still expressed lac Z. In contrast, during culturing in monolayer, no lac Z expression was detectable after 4 weeks. Differentiation status of the chondrocytes was confirmed by histology and immunohistochemistry methods. After successful gene transfer to rabbit chondrocytes the alginate system made it possible to culture lipofected chondrocytes phenotypically stable. Genetically engineered chondrocytes express the lac Z reporter gene over a period of at least 30 weeks. This transfection and culture system provides a promising tool to further investigate the over-expression of growth factors and enzyme inhibitors. Copyright 2002 OsteoArthritis Research Society International.

Condition dependence of male and female genital structures in the seed beetle Callosobruchus maculatus (Coleoptera: Bruchidae).

Science.gov (United States)

Cayetano, L; Bonduriansky, R

2015-07-01

Theory predicts that costly secondary sexual traits will evolve heightened condition dependence, and many studies have reported strong condition dependence of signal and weapon traits in a variety of species. However, although genital structures often play key roles in intersexual interactions and appear to be subject to sexual or sexually antagonistic selection, few studies have examined the condition dependence of genital structures, especially in both sexes simultaneously. We investigated the responses of male and female genital structures to manipulation of larval diet quality (new versus once-used mung beans) in the bruchid seed beetle Callosobruchus maculatus. We quantified effects on mean relative size and static allometry of the male aedeagus, aedeagal spines, flap and paramere and the female reproductive tract and bursal spines. None of the male traits showed a significant effect of diet quality. In females, we found that longer bursal spines (relative to body size) were expressed on low-quality diet. Although the function of bursal spines is poorly understood, we suggest that greater bursal spine length in low-condition females may represent a sexually antagonistic adaptation. Overall, we found no evidence that genital traits in C. maculatus are expressed to a greater extent when nutrients are more abundant. This suggests that, even though some genital traits appear to function as secondary sexual traits, genital traits do not exhibit heightened condition dependence in this species. We discuss possible reasons for this finding. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Identification of Albizia lebbeck seed coat chitin-binding vicilins (7S globulins) with high toxicity to the larvae of the bruchid Callosobruchus maculatus

International Nuclear Information System (INIS)

Souza, A.J.; Ferreira, A.T.S.; Perales, J.; Beghini, D.G.; Fernandes, K.V.S.; Xavier-Filho, J.; Venancio, T.M.; Oliveira, A.E.A.

2011-01-01

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitinbinding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation

Identification of Albizia lebbeck seed coat chitin-binding vicilins (7S globulins) with high toxicity to the larvae of the bruchid Callosobruchus maculatus.

Science.gov (United States)

Souza, A J; Ferreira, A T S; Perales, J; Beghini, D G; Fernandes, K V S; Xavier-Filho, J; Venancio, T M; Oliveira, A E A

2012-02-01

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.

Identification of Albizia lebbeck seed coat chitin-binding vicilins (7S globulins) with high toxicity to the larvae of the bruchid Callosobruchus maculatus

Energy Technology Data Exchange (ETDEWEB)

Souza, A.J. [Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ (Brazil); Ferreira, A.T.S.; Perales, J.; Beghini, D.G. [Laboratório de Toxinologia, Departamento de Fisiologia e Farmacodinâmica, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ (Brazil); Fernandes, K.V.S.; Xavier-Filho, J.; Venancio, T.M.; Oliveira, A.E.A. [Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ (Brazil)

2011-01-27

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitinbinding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.

Identification of Albizia lebbeck seed coat chitin-binding vicilins (7S globulins with high toxicity to the larvae of the bruchid Callosobruchus maculatus

Directory of Open Access Journals (Sweden)

A.J. Souza

2012-02-01

Full Text Available Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.

Exploring the sequence-function relationship in transcriptional regulation by the lac O1 operator.

Science.gov (United States)

Maity, Tuhin S; Jha, Ramesh K; Strauss, Charlie E M; Dunbar, John

2012-07-01

Understanding how binding of a transcription factor to an operator is influenced by the operator sequence is an ongoing quest. It facilitates discovery of alternative binding sites as well as tuning of transcriptional regulation. We investigated the behavior of the Escherichia coli Lac repressor (LacI) protein with a large set of lac O(1) operator variants. The 114 variants examined contained a mean of 2.9 (range 0-4) mutations at positions -4, -2, +2 and +4 in the minimally required 17 bp operator. The relative affinity of LacI for the operators was examined by quantifying expression of a GFP reporter gene and Rosetta structural modeling. The combinations of mutations in the operator sequence created a wide range of regulatory behaviors. We observed variations in the GFP fluorescent signal among the operator variants of more than an order of magnitude under both uninduced and induced conditions. We found that a single nucleotide change may result in changes of up to six- and 12-fold in uninduced and induced GFP signals, respectively. Among the four positions mutated, we found that nucleotide G at position -4 is strongly correlated with strong repression. By Rosetta modeling, we found a significant correlation between the calculated binding energy and the experimentally observed transcriptional repression strength for many operators. However, exceptions were also observed, underscoring the necessity for further improvement in biophysical models of protein-DNA interactions. © 2012 The Authors Journal compilation © 2012 FEBS.

Effector Overlap between the lac and mel Operons of Escherichia coli: Induction of the mel Operon with β-Galactosides.

Science.gov (United States)

Narang, Atul; Oehler, Stefan

2017-05-01

The lac (lactose) operon (which processes β-galactosides) and the mel (melibiose) operon (which processes α-galactosides) of Escherichia coli have a close historical connection. A number of shared substrates and effectors of the permeases and regulatory proteins have been reported over the years. Until now, β-thiogalactosides like TMG (methyl-β-d-thiogalactopyranoside) and IPTG (isopropyl-β-d-thiogalactopyranoside) have not generally been considered to be inducers of the mel operon. The same is true for β-galactosides such as lactose [β-d-galactopyranosyl-(1→4)-d-glucose], which is a substrate but is not itself an inducer of the lac operon. This report shows that all three sugars can induce the mel operon significantly when they are accumulated in the cell by Lac permease. Strong induction by β-thiogalactosides is observed in the presence of Lac permease, and strong induction by lactose (more than 200-fold) is observed in the absence of β-galactosidase. This finding calls for reevaluation of TMG uptake experiments as assays for Lac permease that were performed with mel + strains. IMPORTANCE The typical textbook picture of bacterial operons is that of stand-alone units of genetic information that perform, in a regulated manner, well-defined cellular functions. Less attention is given to the extensive interactions that can be found between operons. Well-described examples of such interactions are the effector molecules shared by the lac and mel operons. Here, we show that this set has to be extended to include β-galactosides, which have been, until now, considered not to effect the expression of the mel operon. That they can be inducers of the mel operon as well as the lac operon has not been noted in decades of research because of the Escherichia coli genetic background used in previous studies. Copyright © 2017 American Society for Microbiology.

76 FR 68124 - Television Broadcasting Services; Fond du Lac, WI

Science.gov (United States)

2011-11-03

... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 [MB Docket No. 09-115, RM-11543; DA 11-1502] Television Broadcasting Services; Fond du Lac, WI AGENCY: Federal Communications Commission. ACTION: Proposed rule. SUMMARY: In this document, the Commission denies a petition for reconsideration of an August 12...

Influence of salt content and processing time on sensory characteristics of cooked "lacón".

Science.gov (United States)

Purriños, Laura; Bermúdez, Roberto; Temperán, Sara; Franco, Daniel; Carballo, Javier; Lorenzo, José M

2011-04-01

The influence of salt content and processing time on the sensory properties of cooked "lacón" were determined. "Lacón" is a traditional dry-cured and ripened meat product made in the north-west of Spain from the fore leg of the pig, following a similar process to that of dry-cured ham. Six batches of "lacón" were salted with different amounts of salt (LS (3 days of salting), MS (4 days of salting) and HS (5 days of salting)) and ripened during two times (56 and 84 days of dry-ripening). Cured odour in all batches studied, red colour and rancid odour in MS and HS batches, flavour intensity in MS batch and fat yellowness, rancid flavour and hardness in the HS batch were significantly different with respect to the time of processing. Appearance, odour, flavour and texture were not significantly affected by the salt content (P>0.05). However, the saltiness score showed significant differences with respect to the salt levels in all studied batches (56 and 84 days of process). The principal component analysis showed that physicochemical traits were the most important ones concerning the quality of dry-cured "lacón" and offered a good separation of the mean samples according to the dry ripening days and salt level. © 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

Complete genome sequence of hypervirulent and outbreak-associated Acinetobacter baumannii strain LAC-4: epidemiology, resistance genetic determinants and potential virulence factors

Science.gov (United States)

Ou, Hong-Yu; Kuang, Shan N.; He, Xinyi; Molgora, Brenda M.; Ewing, Peter J.; Deng, Zixin; Osby, Melanie; Chen, Wangxue; Xu, H. Howard

2015-01-01

Acinetobacter baumannii is an important human pathogen due to its multi-drug resistance. In this study, the genome of an ST10 outbreak A. baumannii isolate LAC-4 was completely sequenced to better understand its epidemiology, antibiotic resistance genetic determinants and potential virulence factors. Compared with 20 other complete genomes of A. baumannii, LAC-4 genome harbors at least 12 copies of five distinct insertion sequences. It contains 12 and 14 copies of two novel IS elements, ISAba25 and ISAba26, respectively. Additionally, three novel composite transposons were identified: Tn6250, Tn6251 and Tn6252, two of which contain resistance genes. The antibiotic resistance genetic determinants on the LAC-4 genome correlate well with observed antimicrobial susceptibility patterns. Moreover, twelve genomic islands (GI) were identified in LAC-4 genome. Among them, the 33.4-kb GI12 contains a large number of genes which constitute the K (capsule) locus. LAC-4 harbors several unique putative virulence factor loci. Furthermore, LAC-4 and all 19 other outbreak isolates were found to harbor a heme oxygenase gene (hemO)-containing gene cluster. The sequencing of the first complete genome of an ST10 A. baumannii clinical strain should accelerate our understanding of the epidemiology, mechanisms of resistance and virulence of A. baumannii. PMID:25728466

The REX survey as a tool to test the beaming model for BL Lacs

CERN Document Server

Caccianiga, A; MacCacaro, T; Wolter, A; Gioia, I M

1999-01-01

In the context of the beaming model (BM) BL Lac and FR I radio galaxies are thought to be the same class of sources seen at different angles. If this picture is correct, we expect to find some transition objects with intermediate properties between the two classes. To date, this intermediate population of objects is missing, probably due to the limiting fluxes of the current X-ray/radio surveys and/or to the criteria used to separate BL Lacs from normal elliptical galaxies. As pointed out by Browne and Marcha (1993), the detection of the transition objects requires particular attention since the "weak" BL Lac nucleus is hidden by the light of the host elliptical galaxy. A useful criterion often used to assess the presence of a non-thermal source, in addition to the stellar emission of the host galaxy, is the Ca contrast at 4000 AA (K/sub 4000/). This quantity, which is defined as the relative depression of the spectrum across 4000 AA, is a typical feature observed in a "normal" elliptical galaxy; the samples ...

Constraining the red shifts of TeV BL Lac objects

Science.gov (United States)

Qin, Longhua; Wang, Jiancheng; Yan, Dahai; Yang, Chuyuan; Yuan, Zunli; Zhou, Ming

2018-01-01

We present a model-dependent method to estimate the red shifts of three TeV BL Lac objects (BL Lacs) through fitting their (quasi-)simultaneous multi-waveband spectral energy distributions (SEDs) with a one-zone leptonic synchrotron self-Compton model. Considering the impact of electron energy distributions (EEDs) on the results, we use three types of EEDs to fit the SEDs: a power-law EED with exponential cut-off (PLC), a log-parabola (PLLP) EED and the broken power-law (BPL) EED. We also use a parameter α to describe the uncertainties of the extragalactic background light models, as in Abdo et al. We then use a Markov chain Monte Carlo method to explore the multi-dimensional parameter space and obtain the uncertainties of the model parameters based on the observational data. We apply our method to obtain the red shifts of three TeV BL Lac objects in the marginalized 68 per cent confidence, and find that the PLC EED does not fit the SEDs. For 3C66A, the red shift is 0.14-0.31 and 0.16-0.32 in the BPL and PLLP EEDs. For PKS1424+240, the red shift is 0.55-0.68 and 0.55-0.67 in the BPL and PLLP EEDs. For PG1553+113, the red shift is 0.22-0.48 and 0.22-0.39 in the BPL and PLLP EEDs. We also estimate the red shift of PKS1424+240 in the high stage to be 0.46-0.67 in the PLLP EED, roughly consistent with that in the low stage.

Infrared polarimetry and photometry of BL Lac objects

International Nuclear Information System (INIS)

Impey, C.D.; Williams, P.M.

1984-01-01

Photometry and polarimetry in the JHK wavebands have now been obtained for 25 BL Lac objects. Several new objects have been monitored for periods of up to five days, and accumulated data is sufficient for a statistical analysis of polarization properties. The selection effects operating on this sample are examined first. A power-law spectrum is consistent with the spectra of all but three objects. A number of important new results are reported. (author)

Essais d'adaptation de production massive de juvéniles de Clarias gariepinus en conditions rurales

Directory of Open Access Journals (Sweden)

Micha, JC.

2005-01-01

Full Text Available Adaptive Trials for Intensive Clarias gariepinus fingerling to Rural Conditions. Artificial reproduction and fingerling production of the African catfish Clarias gariepinus (Burchell 1822 have been tested under less controlled conditions to adapt the intensive technology used by Aquafarm (Tihange, Belgium to rural conditions present in developing countries. The main aim was to compare the efficiency of ovaprim a synthesised hormone with catfish pituitary extracts. Fecundity and quality of eggs (egg weight were not significantly different. Incubation results on water hyacinth and on mosquito mesh frames were compared to those obtained in Zoug jars; the latter showed a higher hatching rate (67% than water hyacinth (39% and mosquito mesh frames (44%. Larvae were stocked at different stocking rates in ponds (T1: 800 larvae.m-3 and T2: 1600 larvae. m-3 and in tanks (T3: 3200 larvae.m-3 et T4: 6400 larvae.m-3. After a 50-day nursing period, no significant difference (P> 0.05 was observed for specific growth rate (SGR and survival rate, but better SGR were observed in ponds (18.34%.d-1 than in tanks (16.81%.d-1. In general, production was slightly higher in tanks than in ponds being related to a higher stocking density. Significantly higher harvests were obtained from tanks with higher stocking densities but the sizes of the larvae were very heterogeneous. In such case, it is recommended to grade the larvae at 6 or 7 days intervals using different mesh sizes (from 3 to 5 mm. These less intensive rearing conditions gave nevertheless good fingerling productions.

Transformation of lacZ using different promoters in the commercially ...

African Journals Online (AJOL)

Yomi

2012-01-26

Jan 26, 2012 ... forced growth under unnatural conditions. In order to ... yezoensis include the gluc, cat, GUS and GFP genes. (Cheney et al. ... bacterial lacZ gene encodes the β-galactosidase enzyme which is capable of .... Table 1. Effect of viral promoters on transient β-galactosidase activity in microparticle bombarded G.

The Sedentary Multi-Frequency Survey. I. Statistical Identification and Cosmological Properties of HBL BL Lacs

OpenAIRE

Giommi, P.; Menna, M. T.; Padovani, P.

1999-01-01

We have assembled a multi-frequency database by cross-correlating the NVSS catalog of radio sources with the RASSBSC list of soft X-ray sources, obtaining optical magnitude estimates from the Palomar and UK Schmidt surveys as provided by the APM and COSMOS on-line services. By exploiting the nearly unique broad-band properties of High-Energy Peaked (HBL) BL Lacs we have statistically identified a sample of 218 objects that is expected to include about 85% of BL Lacs and that is therefore seve...

Concentration of electrolyte reserves of the juvenile african catfish clarias gariepinus (burchell, 1822) exposed to sublethal concentrations of portland cement powder in solution

International Nuclear Information System (INIS)

Adamu, M.K.; Francis, O.A.

2008-01-01

The study investigated the effect of sublethal concentrations (39.10, 19.55, 9.87 and 0.00 mg/l) of Portland cement powder in solution on the electrolyte reserves (sodium, potassium, calcium, chloride and inorganic phosphorus) in the serum, liver and kidney of the juvenile African catfish Clarias gariepinus after a 15 day exposure period. The basic function of the determined electrolyte reserves in the body lies in controlling fluid distribution, intra and extra cellular acidobasic equilibrium, maintaining osmotic pressure of body fluid and normal neuro-muscular irritability. The result revealed significant (P 0.05) changes in inorganic phosphorus. Sodium, calcium, chloride and inorganic phosphorus and potassium were significantly (P 0.05) different in liver and kidney, respectively. Ipso-facto, the effector organs viz: liver and kidney of teleost species - Clarias gariepinus which are primarily responsible for regulating water and ionic movement between external and internal milieu of fishes are susceptible to deleterious effects of Portland cement powder thus sublethal concentration (39.10 mg/l) of Portland cement powder in solution after a 15 day exposure has been most toxic and debilitating to the test fish. (author)

Role of various fishmeal ingredients on sangkuriang catfish Clarias sp. growth

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Nur Bambang Priyo Utomo

2015-05-01

Full Text Available ABSTRACT This research was aimed to evaluate the role of fish meal from different raw materials in improving growth performance of sangkuriang catfish Clarias sp. The source of raw materials used were derived from trash fish, salted fish, and head fish eal. Fish reared for 44 days and were given feed test three times per day at 08.00, 12.00, and 16.00. Biomass weight of the experimental fish used were 38.49±1.61 g. The fish reared on the aquarium of 60x50x40 cm3 and by using recirculation system. The results showed that fish meal derived from trash fish provide the best result for feed consumption, daily growth rate, absolute length, biomass, retention of protein, retention of fat, feed efficiency, feed conversion (P>0.05. However, it does not significantly different on the survival of fish (P>0.05. The data showed that the use of trash fish meal resulted on the best growth performance of sangkuriang catfish. It was indicated that the trash-fish meal might be used as the main protein source of sangkuriang catfish feed. Keywords: catfish, growth, at satiation, fish meal  ABSTRAK Penelitian ini bertujuan untuk mengevaluasi pakan uji yang menggunakan sumber tepung ikan dari bahan baku berbeda dalam meningkatkan kinerja pertumbuhan lele sangkuriang Clarias sp. Sumber tepung ikan yang digunakan berasal dari ikan rucah, ikan asin, dan kepala ikan, yang memiliki umum digunakan sebagai salah satu bahan baku pakan lokal. Ikan diberi pakan at satiation selama 44 hari dengan frekuensi tiga kali sehari, yaitu pada pukul 08.00, 12.00, dan 16.00. Biomassa rata-rata ikan uji yang digunakan adalah 38,49±1,61 g. Ikan dipelihara dalam akuarium berukuran 60x50x40 cm3 dan dengan menerapkan sistem resirkulasi. Hasil penelitian menunjukkan bahwa tepung ikan yang berasal dari ikan rucah mampu memberikan hasil terbaik dalam meningkatkan kinerja pertumbuhan ikan uji. Hal ini ditunjukkan oleh nilai kinerja pertumbuhan seperti jumlah konsumsi pakan, laju

Hydrogeologic characteristics of domains of sparsely fractured rock in the granitic Lac Du Bonnet Batholith, southeastern Manitoba, Canada

International Nuclear Information System (INIS)

Stevenson, D.R.; Kozak, E.T.; Davison, C.C.; Gascoyne, M.; Broadfoot, R.A.

1996-06-01

The hydrogeologic characteristics of the granitic Lac du Bonnet batholith in southeastern Manitoba have been studied since 1978, as part of AECL's program to assess the concept of disposing of Canada's nuclear fuel waste deep within plutonic rocks of the Canadian Shield (Davison et al. 1994a). These studies have included an extensive program of drilling, logging, testing, sampling and monitoring in 19 deep surface boreholes drilled at Grid areas located across the Lac du Bonnet batholith, at the Whiteshell Laboratory (WL), and in surface and underground boreholes at the Underground Research Laboratory (URL). Based on these investigations domains of low permeability, sparsely fractured rock (SFR) have been identified in the Lac du Bonnet batholith

PERFORMA REPRODUKSI IKAN LELE MUTIARA (Clarias gariepinus

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Bambang Iswanto

2016-12-01

Full Text Available Ikan lele Mutiara merupakan salah satu strain ikan lele Afrika (Clarias gariepinus yang memiliki keunggulan performa pertumbuhan, efisiensi pakan, keseragaman ukuran, serta ketahanan terhadap penyakit dan lingkungan. Pengggunaan benih ikan lele Mutiara dalam kegiatan budidaya dapat menghasilkan produktivitas yang lebih tinggi, sehingga permintaan benihnya semakin meningkat. Jumlah dan kualitas benih yang dihasilkan ditentukan oleh karakteristik reproduksi induknya. Penelitian ini bertujuan untuk mengevaluasi performa reproduksi ikan lele Mutiara, antara lain umur awal matang gonad, indeks gonadosomatik dan ovisomatik, fekunditas, derajat fertilisasi, derajat penetasan, dan waktu rematurasi. Penentuan umur awal matang gonad dilakukan melalui pembedahan calon induk ikan lele Mutiara sejak berumur empat bulan. Pengamatan indeks gonadosomatik dan ovisomatik, fekunditas, derajat fertilisasi, derajat penetasan, dan waktu rematurasi dilakukan terhadap induk ikan lele Mutiara berumur 10 bulan yang digunakan dalam proses pemijahan alami dan buatan. Calon induk dan induk ikan lele Mutiara yang digunakan pada penelitian ini dipelihara dalam kolam tanah dan diberi pakan buatan komersial dengan kadar protein 30% untuk calon induk dan 35% untuk induk. Hasil penelitian ini menunjukkan bahwa ikan lele Mutiara mulai matang gonad pada umur lima bulan. Induk jantan ikan lele Mutiara yang matang gonad memiliki indeks gonadosomatik sebesar 0,22%-1,47%; sedangkan indeks ovisomatik induk betina berkisar 10,30%-21,33%; dengan fekunditas berkisar 72.700-165.900 butir/kg bobot induk (rata-rata 102.400 ± 25.000 butir/kg bobot induk. Pemijahan buatan induk ikan lele Mutiara menghasilkan derajat fertilisasi berkisar 76,53%-99,22% (rata-rata 91,48 ± 5,38% dan derajat penetasan berkisar 64,93%-91,96% (rata-rata 80,45 ± 6,28%. Waktu rematurasi induk jantan ikan lele Mutiara sekitar dua minggu, sedangkan pada induk betina selama 1,5 bulan. Mutiara is one of several strains

African catfish (Clarias gariepinus Burchell, 1822. Thematic bibliography

Directory of Open Access Journals (Sweden)

I. Hrytsyniak

2017-12-01

Full Text Available Purpose. Forming a thematic bibliographic list of publications on certain issues of African catfish (Clarias gariepinus biology and cultivation in Ukraine and abroad, as well as concerning the effects of rearing conditions on physiological, biochemical and fish-breeding characteristics of clariids. Methods. The complete and selective methods were applied in the process of the systematic search. The bibliographic core have been formed with the publications in Ukrainian, Russian and English from the fund of scientific library of the Institute of Fisheries NAAS of Ukraine. Results. There was composed the thematic list of publications with a total quantity of 112 sources covering the time interval from 1978 to 2017, as well as an article from the "Aquaculture" journal, dated 2018, and including the fish-biological characteristics of African catfish as representative of Siluriformes order, Clariidae family. The literary sources are arranged in alphabetical order by author or title, and described according to DSTU 8302:2015 “ Information and documentation. Bibliographic reference. General principles and rules of composition”, with the amendments (code UKND 01.140.40, as well as in accordance with the requirements of APA style — international standard of references. Practical value. The list may be useful for scientists, practitioners, students, whose area of interests covers the questions of cultivation and study of the biological features of African catfish.

Nutritional Transition Period in Early Larvae Clarias Gariepinus

International Nuclear Information System (INIS)

Ing, N.S.; Chew, H.H.

2015-01-01

The nutritional transition period of Clarias gariepinus were described based on the early development from hatching to 120 hours after hatching (hAH) reared at 27.5 - 28.6 degree Celsius. Newly hatched larvae had a large greenish yolk sac volume (0.99 ± 0.31 mm"3) located below a straight undeveloped digestive tract, mouth not opened, eyes unpigmented and the larvae lie on the bottom of rearing tank. During endogenous feeding period, the larval feeding system has developed rapidly with development oesophagus. Yolk sac were not completely depleted at the onset of exogenous feeding (36 hAH, 0.19 ± 0.11 mm"3), and a period of mixed nutrition was observed up to 68 hAH when yolk was completely exhausted. Yolk sac volume was significantly different by time at hatching, 6, 12 and 18 to 36 hAH (ANOVA, P<0.05). At 36 hAH, the larvae commenced feeding once morphologically developed with opened anus, functional jaw and intestine, and demonstrated horizontally swimming. The rudimentary chemoreceptors like olfactory organs and taste buds that were found on the barbels and oral cavity assisted in food detection and commenced feeding without vision. Due to the cannibalistic behaviour at early stage, feed are suggested to be provided during 36 hAH and avoided delay feeding in the larval rearing. (author)

[Fond du Lac archeological resources within the Draft Area Recommendation Report

International Nuclear Information System (INIS)

Danz, D.L.

1986-01-01

Research into archaeological resources of the Fond du Lac Band within the DOE proposed high-level nuclear waste sites resulted in the discovery of four traditional ancestral sites. A number of ancestral sites that are located within other proposed repository sites were also discovered

Spinal cord self-repair during tail regeneration in Polypedates maculatus and putative role of FGF1 as a neurotrophic factor.

Science.gov (United States)

Hota, Jutshina; Pati, Sushri Sangita; Mahapatra, Pravati Kumari

2018-03-01

Spinal cord injury could be fatal in man and often results in irreversible medical conditions affecting mobility. However, anuran amphibians win over such pathological condition by the virtue of regeneration abilities. The tail of anuran tadpoles therefore allures researchers to study spinal cord injury and self- repair process. In the present study, we inflicted injury to the spinal cord by means of surgical transection of the tail and investigated the self-repair activity in the tadpoles of the Indian tree frog Polypedates maculatus. We also demonstrate for the first time by immunofluorescence localization the expression pattern of Fibroblast Growth Factor1 (FGF1) during spinal cord regeneration which has not been documented earlier in anurans. FGF1, bearer of the mitogenic and neurotrophic properties seems to be expressed by progenitor cells that facilitate regeneration. Spinal cord during tail regeneration in P. maculatus attains functional recovery within a span of 2 weeks thus enabling the organism to survive in an aquatic medium till metamorphosis. Moreover, during the course of spinal cord regeneration in the regenerating tail, melanocytes showed an interesting behaviour as these neural crest derivatives were missing near the early regenerates until their reappearance where they were positioned in close proximity with the regenerated spinal cord as in the normal tail. Copyright © 2017 Elsevier B.V. All rights reserved.

Radiocarbon measurements at LAC-UFF: Recent performance

Energy Technology Data Exchange (ETDEWEB)

Linares, Roberto, E-mail: rlinares@if.uff.br [Laboratório de Radiocarbono, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza, s/n, Niterói 24230-346 (Brazil); Macario, Kita D. [Laboratório de Radiocarbono, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza, s/n, Niterói 24230-346 (Brazil); Santos, Guaciara M. [Earth System Science, University of California, Irvine, B321 Croul Hall, Irvine, CA 92697-3100 (United States); Carvalho, Carla [Laboratório de Radiocarbono, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza, s/n, Niterói 24230-346 (Brazil); Departamento de Geoquímica, Universidade Federal Fluminense, Outeiro São João Batista, s/n, Niterói 24020-141 (Brazil); Santos, Hellen C. dos; Gomes, Paulo R.S.; Castro, Maikel D.; Oliveira, Fabiana M.; Alves, Eduardo Q. [Laboratório de Radiocarbono, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza, s/n, Niterói 24230-346 (Brazil)

2015-10-15

In 2012 a single stage accelerator mass spectrometer from NEC was installed at the Radiocarbon Laboratory of Universidade Federal Fluminense (LAC-UFF), Niterói, Brazil. Here, we present a status report of our facility. We discuss some modifications applied to our combustion protocol in an attempt to reduce our procedural blank, mostly to processed organic samples. Measurements of reference materials indicate low precision and accuracy that are partially related to beam optics through the acceleration tube. We observed that once the beam current intensity increases the measured {sup 13}C{sup +}/{sup 12}C{sup +} becomes erratic. Therefore, in order to maintain the AMS-δ{sup 13}C values within reasonable values, so that fractionation corrections using the spectrometer {sup 13}C{sup +}/{sup 12}C{sup +} values does not affect the final {sup 14}C results, we are forced to limit the {sup 12}C{sup −} beam intensity to ⩽30 μA. This requirement was confirmed during our accuracy tests, when measuring selected annual tree-rings wood samples from a Parana pine (Araucaria angustifolia) between 1927 and 1997 previously measured at the Keck Carbon Cycle AMS Facility (KCCAMS), at the University of California, Irvine (UCI). At the LAC-UFF tree-ring wood samples were processed and measured in 4 different batches during a period of about 5 months. The {sup 14}C results were later compared to the high-precision data obtained at KCCAMS/UCI and reached a good agreement. Recently a problem associated with graphitization yield were finally identified and new measurements with secondary standards are promising.

Effet des conditions climatiques sur le niveau du lac Sidi Ali (Moyen Atlas, Maroc)

OpenAIRE

Sayad, Ahmed; Chakiri, Saïd; Martin, Claude; Bejjaji, Zohra; Echarfaoui, Hassan

2012-01-01

Le lac Sidi Ali est un lac naturel d'altitude (2070-2080 m), sans exutoire superficiel, déterminé par le barrage d'une coulée basaltique. Doté d'un bassin versant apparent de 15,6 km2, il est alimenté par des eaux de ruissellement et par des sources karstiques. Son niveau subit des variations très fortes, annuelles et interannuelles, sous le contrôle des conditions climatiques, et en particulier des pluies et de l'évapotranspiration. Les périodes de sécheresse qui ont marqué les trois dernièr...

Screening of selenium containing proteins in the Tris-buffer soluble fraction of African catfish (Clarias gariepinus) fillets by laser ablation-ICP-MS after SDS-PAGE and electroblotting onto membranes

NARCIS (Netherlands)

Pedrero, Z.; Madrid, Y.; Camara, C.; Schram, E.; Luten, J.B.; Feldmann, I.; Waentig, L.; Hayen, H.; Jakubowski, N.

2009-01-01

The anti-carcinogenic properties of selenium against certain types of cancer when present in organic forms justify the increasing interest in development of selenium fortified food. In this particular study, African catfish (Clarias gariepinus) were fed with a Se-enriched diet in order to enhance

Dynamics and bistability in a reduced model of the lac operon

Science.gov (United States)

Yildirim, Necmettin; Santillán, Moisés; Horike, Daisuke; Mackey, Michael C.

2004-06-01

It is known that the lac operon regulatory pathway is capable of showing bistable behavior. This is an important complex feature, arising from the nonlinearity of the involved mechanisms, which is essential to understand the dynamic behavior of this molecular regulatory system. To find which of the mechanisms involved in the regulation of the lac operon is the origin of bistability, we take a previously published model which accounts for the dynamics of mRNA, lactose, allolactose, permease and β-galactosidase involvement and simplify it by ignoring permease dynamics (assuming a constant permease concentration). To test the behavior of the reduced model, three existing sets of data on β-galactosidase levels as a function of time are simulated and we obtain a reasonable agreement between the data and the model predictions. The steady states of the reduced model were numerically and analytically analyzed and it was shown that it may indeed display bistability, depending on the extracellular lactose concentration and growth rate.

NEW HIGH- z FERMI BL LACS WITH THE PHOTOMETRIC DROPOUT TECHNIQUE

Energy Technology Data Exchange (ETDEWEB)

Kaur, A.; Ajello, M.; Hartmann, D. H.; Paliya, V. S. [Department of Physics and Astronomy, Clemson University, SC 29634-0978 (United States); Rau, A.; Greiner, J.; Bolmer, J.; Schady, P. [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße 1, D-85748 Garching (Germany); Domínguez, A., E-mail: akaur@g.clemson.edu [Grupo de Altas Energías, Universidad Complutense, E-28040 Madrid (Spain)

2017-01-01

Determining redshifts for BL Lacertae (BL Lac) objects using the traditional spectroscopic method is challenging due to the absence of strong emission lines in their optical spectra. We employ the photometric dropout technique to determine redshifts for this class of blazars using the combined 13 broadband filters from Swift -UVOT and the multi-channel imager GROND at the MPG 2.2 m telescope at ESO's La Silla Observatory. The wavelength range covered by these 13 filters extends from far-ultraviolet to the near-infrared. We report results on 40 new Fermi- detected BL Lacs with the photometric redshift determinations for five sources, with 3FGL J1918.2–4110 being the most distant in our sample at z  = 2.16. Reliable upper limits are provided for 20 sources in this sample. Using the highest energy photons for these Fermi -LAT sources, we evaluate the consistency with the gamma-ray horizon due to the extragalactic background light.

cas du lac Fetzara, région de Annaba

African Journals Online (AJOL)

ruissellement, elles acquièrent une nouvelle composition différente de celle des eaux de pluie. Les apports par les précipitations météoriques. Chaque mois pluvieux a fait l'objet d'une analyse chimique et une moyenne des concentrations des eaux apportées au lac a été estimée. La quantité des éléments apportés par.

Computing Optical Variable Periods of BL Lac Object S5 0716+ 714 ...

Indian Academy of Sciences (India)

Computing Optical Variable Periods of BL Lac Object S5 0716+ 714 ... The study of long-term periodical variation is an important way to get the charac- ... continuous Fourier transform together, define a window function, and finally obtain.

Characterisation of Catfish (Clarias Batrachus) Oil: β-Cyclodextrin Inclusion Complex

International Nuclear Information System (INIS)

Zaibunnisa Abdul Haiyee; Nor Izzatul Adyani Yahya; Norizzah Abd Rashid; Dzulkifly Mat Hashim

2016-01-01

Catfish is a cheap source of essential omega-3 fatty acids especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Catfish oil was extracted and clean-up using pressurised liquid extraction (PLE) from the viscera of catfish (Clarias batrachus). However, the characteristics of catfish oils are sticky, strong fishy odour and can easily be oxidised with short shelf-life. In this study, catfish oil was converted into powder by formation of inclusion complex with β-cyclodextrin. Inclusion complex was prepared by using co-precipitation and kneading methods and compared with physical mixture. The inclusion complex formed were characterised by using field emission scanning electron microscopy (FESEM), differential scanning calorimeter (DSC) and fourier transform infrared spectroscopy (FTIR). FESEM images revealed that inclusion complex using co-precipitation and kneading methods has smaller in crystal sizes and appeared as different morphology compared to physical mixture. DSC proved that co-precipitation method was able to form new solid phase due to shifting of melting point to higher temperature (145.22 degree Celcius). FTIR supported the result by proving strengthening of carbonyl group (C=O). Therefore, co-precipitation method was able to successfully produce inclusion complex of catfish oil, β-cyclodextrin. (author)

Irradiation disinfestation of cowpea seeds to control southern cowpea beetle Callosbruchus maculatus (Fabricius) (Coleoptera Bruchidae)

International Nuclear Information System (INIS)

El-Kady, E.A.; Hekal, A.M.; El-Refai, S.

1987-01-01

The possibility of using gamma radiation as an alternative to fumigation or direct chemical applications for the control of stored-products insects was investigated in the laboratory and in a warehouse in Cairo, Egypt. Polyethylene bags of the type used in local markets were filled with cowpeas [Vigna unguiculata] Callosobruchus maculatus and irradiated at 400, 600 or 800 Gy [4, 6 or 8 krad]. All the treatments were effective, and no living adults infested by were found in the bags until 3 months later, when adults from outside penetrated the bags with their mandibles. It is therefore recommended that 4 krad should be administered for initial control, but that treated cowpeas should be stored in polypropylene rather than polyethylene bags in order to prevent reinfestation

Activity of the thyroid and the pituitary gland in the viviparous Cyprinodonts Lebistes reticulatus (Peters), Xiphophorus helleri Heckel and Xiphophorus maculatus Günther during the development of the gonopodium

NARCIS (Netherlands)

Stolk, A.

1959-01-01

A description is given of the activity of the thyroid and of the pituitary gland during the development of the gonopodium in the viviparous Cyprinodonts Lebistes reticulatus (Peters), Xiphophorus helleri (Heckel) and Xiphophorus maculatus (Günther). During this process the thyroid gland and the

Infrared polarimetry and photometry of BL Lac objects. 2

Energy Technology Data Exchange (ETDEWEB)

Impey, C D [Hawaii Univ., Honolulu (USA). Inst. for Astronomy; Brand, P W.J.L. [Edinburgh Univ. (UK). Dept. of Astronomy; Wolstencroft, R D [Royal Observatory, Edinburgh (UK); Williams, P M [United Kingdom Infrared Telescope Unit, Hilo, Hawaii (USA)

1984-07-15

Photometry and polarimetry in the JHK wavebands have now been obtained for 25 BL Lac objects. Several new objects have been monitored for periods of up to five days, and accumulated data is sufficient for a statistical analysis of polarization properties. The selection effects operating on this sample are examined first. A power-law spectrum is consistent with the spectra of all but three objects. A number of important new results are reported.

A source of artifact in the lacZ reversion assay in Escherichia coli.

Science.gov (United States)

Hoffmann, George R; Gray, Carol L; Lange, Paulina B; Marando, Christie I

2015-06-01

The lacZ reversion assay in Escherichia coli measures point mutations that occur by specific base substitutions and frameshift mutations. The tester strains cannot use lactose as a carbon source (Lac(-)), and revertants are easily detected by growth on lactose medium (Lac(+)). Six strains identify the six possible base substitutions, and five strains measure +G, -G, -CG, +A and -A frameshifts. Strong mutagens give dose-dependent increases in numbers of revertants per plate and revertant frequencies. Testing compounds that are arguably nonmutagens or weakly mutagenic, we often noted statistically significant dose-dependent increases in revertant frequency that were not accompanied by an absolute increase in numbers of revertants. The increase in frequency was wholly ascribable to a declining number of viable cells owing to toxicity. Analysis of the conditions revealed that the frequency of spontaneous revertants is higher when there are fewer viable cells per plate. The phenomenon resembles "adaptive" or "stress" mutagenesis, whereby lactose revertants accumulate in Lac(-) bacteria under starvation conditions in the absence of catabolite repression. Adaptive mutation is observed after long incubation and might be expected to be irrelevant in a standard assay using 48-h incubation. However, we found that elevated revertant frequencies occur under typical assay conditions when the bacterial lawn is thin, and this can cause increases in revertant frequency that mimic chemical mutagenesis when treatments are toxic but not mutagenic. Responses that resemble chemical mutagenesis were observed in the absence of mutagenic treatment in strains that revert by different frameshift mutations. The magnitude of the artifact is affected by cell density, dilution, culture age, incubation time, catabolite repression and the age and composition of media. Although the specific reversion assay is effective for quickly distinguishing classes of mutations induced by potent mutagens, its

THE PREVALENCE OF Salmonella sp., Listeria sp. AND Aeromonas spp. IN CATFISH (CLARIAS (Clarias gariepinus AND TILAPIA (Tilapia mossambica BY PELLETING METHOD

Directory of Open Access Journals (Sweden)

Titik Budiati

2013-06-01

Full Text Available The aim of this study was to modify the isolation methods of Aeromonas sp., Salmonella spp., and Listeria sp. in catfish (Clarias gariepinus and tilapia (Tilapia mossambica obtained from wet markets and ponds in Malaysia by pelleting the sample. A total of 108 samples (32 catfish intestines, 32 tilapia intestines, and 44 water samples were obtained from nine wet markets and eight ponds. The modified method was employed by pelleting the samples and followed by either implementing pre-enrichment or without pre-enrichment on the isolation of Salmonella and Listeria spp. The modified method (by pelleting the sample in combination with pre-enrichment was the most efficient for Salmonella and Listeria isolation. The sensitivity of the modified Salmonella isolation method was 0.53 and 0.73 for fish and water samples, respectively. The sensitivity of the modified Listeria method was 1 and 0.92 for fish and water samples, respectively. However, the sensitivity of the method by pelleting the sample was similar to those of non-pelleting the sample on Aeromonas isolation. Five species of Aeromonas spp., seven serovars of Salmonella sp., and four species of Listeria sp. were observed in catfish, tilapia and water samples. Overall, by pelleting the sample offered the beneficial to isolate Aeromonas spp., Salmonella sp. and Listeria spp. in catfish, tilapia and water.

New species of Cerambycinae from the Neotropical Region, and nomen novum for Anelaphus maculatus Galileo, Martins, and Santos-Silva, 2014 (Elaphidiini).

Science.gov (United States)

Galileo, Maria Helena M; Martins, Ubirajara R; Santos-Silva, Antonio

2015-07-17

Six new species and one new genus are described: Criodion spinosum sp. nov. (Cerambycini), from Bolivia; Eburodacrys wappesi sp. nov. and Eburodacrys skillmani sp. nov. (Eburiini), from Bolivia; Eupempelus rileyorum sp. nov. (Heteropsini) from Panama; Sphalloeme mexicana sp. nov. (Oemini), from Mexico; Wappesoeme camiri sp. nov., new genus (Oemini), from Bolivia. Wappesoeme, Eburodacrys wappesi, E. skillmani, Eupempelus rileyorum, and Criodion spinosum are included in previously published keys. Anelaphus erakyra nomen novum for A. maculatus Galileo et al., 2014 is established.

Effect of the partial NaCl substitution by other chloride salts on the volatile profile during the ripening of dry-cured lacón

Energy Technology Data Exchange (ETDEWEB)

Dominguez, R.; Munekata, P.E.; Cittadini, A.; Lorenzo, J.M.

2016-07-01

The influence of three salting treatments (treatment II: 50% NaCl-50% KCl; III: 45% NaCl-25% KCl-20% CaCl2-10% MgCl2; IV: 30% NaCl-50% KCl-15% CaCl2-5% MgCl2) on the formation of volatile compounds throughout the process was studied and compared to those of a control “lacón” (treatment I: 100% NaCl). There was an intense formation of volatile compounds throughout the processing, particularly during the dry-ripening stage. The most abundant chemical family in all the formulations, in the final product was hydrocarbons followed by aldehydes. The total volatile compound release was more intense in the control “lacóns” (1164 AU×106 ·g–1dry matter) than in “lacóns” from formulations II, III and IV (817–891 AU×106 ·g−1dry matter). The “lacóns” from formulation I showed the highest amounts of aldehydes. The “lacóns” from formulations I and II presented the highest amounts of hydrocarbons. The main conclusion is that the replacement of NaCl produces changes in the volatile profile and could be affect the aroma of “lacón”. (Author)

The effect of stochasticity on the lac operon: an evolutionary perspective.

Directory of Open Access Journals (Sweden)

Milan van Hoek

2007-06-01

Full Text Available The role of stochasticity on gene expression is widely discussed. Both potential advantages and disadvantages have been revealed. In some systems, noise in gene expression has been quantified, in among others the lac operon of Escherichia coli. Whether stochastic gene expression in this system is detrimental or beneficial for the cells is, however, still unclear. We are interested in the effects of stochasticity from an evolutionary point of view. We study this question in the lac operon, taking a computational approach: using a detailed, quantitative, spatial model, we evolve through a mutation-selection process the shape of the promoter function and therewith the effective amount of stochasticity. We find that noise values for lactose, the natural inducer, are much lower than for artificial, nonmetabolizable inducers, because these artificial inducers experience a stronger positive feedback. In the evolved promoter functions, noise due to stochasticity in gene expression, when induced by lactose, only plays a very minor role in short-term physiological adaptation, because other sources of population heterogeneity dominate. Finally, promoter functions evolved in the stochastic model evolve to higher repressed transcription rates than those evolved in a deterministic version of the model. This causes these promoter functions to experience less stochasticity in gene expression. We show that a high repression rate and hence high stochasticity increases the delay in lactose uptake in a variable environment. We conclude that the lac operon evolved such that the impact of stochastic gene expression is minor in its natural environment, but happens to respond with much stronger stochasticity when confronted with artificial inducers. In this particular system, we have shown that stochasticity is detrimental. Moreover, we demonstrate that in silico evolution in a quantitative model, by mutating the parameters of interest, is a promising way to unravel

Complete replacement of fish meal by other animal protein sources on growth performance of Clarias gariepinus fingerlings

Directory of Open Access Journals (Sweden)

Arnauld S. M. Djissou

2016-10-01

Full Text Available Abstract To completely replace the fish meal by a mixture of earthworm and maggot meals, experimental diets were tested during 42 days on Clarias gariepinus fingerlings. Five isoproteic and isoenergetic diets (40 % crude protein and 17.9 ± 0.3 kJ g−1 including the control diet (D1 based on fish meal, were formulated. All these diets satisfied the essential amino acids requirements of C. gariepinus fingerlings. These diets were tested on triplicate groups of 50 fishes (initial body weight: 3 ± 0.1 g bred in tank (0.5 m3. The approximate ratios 2:5; 1:4; 1:12 and 0:1 between the earthworm meal and the maggot meal were used, respectively, to formulate four diets D2, D3, D4 and D5 without fish meal. After the feeding period, significant differences (P < 0.05 were observed on growth, feed utilization between control diet (D1 and test diets (D2–D5. Fish fed earthworm- and maggot-based diets were grown better than those fed the control diet. Survival and feed utilization were not significantly affected by the ratio between earthworm meal and maggot meal in the test diets. Lipid content was higher in carcass and fillet of fishes fed earthworm- and maggot meals-based diets than that of those fed fish meal-based diet. This study indicates that when the ratio 2:5 between the earthworm meal and the maggot meal is used to entirely replace fish meal and the ratio lysine/arginine of the diet is inferior to 1, the growth performances and feed utilization of Clarias gariepinus fingerlings are improved.

Analyses de la dégradation du lac Kinkony pour la conservation du ...

African Journals Online (AJOL)

Le lac Kinkony fait partie des habitats clefs pour la biodiversité du Complexe des ... provide favoured habitat for numerous endemic and endangered avian, fish ... on fauna is essential for developing regional conservation and natural resource ...

X-ray emission from BL Lac objects: Comparison to the synchrotron self-Compton models

International Nuclear Information System (INIS)

Schwartz, D.A.; Madejski, G.; Ku, W.H.-M.

1982-01-01

As one part of our joint study of the X-ray properties of BL Lac objects, the authors compare the measured X-ray flux densities with those predicted using the synchrotron self-Compton (SSC) formalism (Jones et al. 1974). Naive application of the formalism predicts X-ray fluxes from 10 -3 to 10 5 those observed. They therefore ask what we can learn by simply assuming the SSC mechanism, and looking for ways to reconcile the observed and measured X-ray fluxes. This paper reports investigation of beaming factors due to relativistic ejection of a radiation source which is isotropic in its own rest frame. The authors conclude that large Lorentz factors, GAMMA approximately > 10, do not apply to BL Lac objects as a class. (Auth.)

Mode d'exploitation et durabilité de la pêche de Oreochromis niloticus (Linnaeus, 1758, Clarias gariepinus (Burchell, 1822 et Gymnarchus niloticus (Cuvier, 1829 dans le lac de barrage du Sourou (Burkina Faso

Directory of Open Access Journals (Sweden)

Dialla, Z.

2016-01-01

Full Text Available Mode of Operation and Sustainability of Oreochromis niloticus (Linnaeus, 1758, Clarias gariepinus (Burchell, 1822 and Gymnarchus niloticus (Cuvier, 1829 Fisheries in the Sourou Dam Lake (Burkina Faso. This research on fishery exploitation in the Sourou dam raises the issue of sustainable management of common property. The central hypothesis is that the effectiveness of co-management for sustainable fishing practices is related to the level of ownership of that management and actors' games by fishing communities. In analysing co-management induced effects on fishing practices and exploitation of C. gariepinus, O. niloticus and G. niloticus species, related to its implementation in Sourou fishery, a research methodology that combines qualitative and quantitative methods is used. Socio-economic surveys were conducted with 30 fishermen in three villages bordering the fishery. Biological surveys were also conducted with catches of C. gariepinus, O. niloticus and G. niloticus of these fishermen,. The results indicate a weak ownership of the co-management model by fishermen and the strategies of actors that consist to minimize the costs of the sustainable management of fisheries resources at individual level. Indeed, even when informed of fisheries regulations, fishermen use prohibited fishing equipment (54.1% of the catches of studied species, and fishi illegally (43.3% of the fishermen. Furthermore, significant proportions of each studied species are captured before their first maturity sizes (52.2% of C. gariepinus, 15.8% of G. niloticus and 14.3% of O. niloticus. So, the central hypothesis is verified because the weak ownership of co-management by fishing communities and the actors' strategies do not encourage them to develop a responsible behavior for sustainable fishing.

A geological reconnaissance study of the Lac du Bonnet batholith

International Nuclear Information System (INIS)

Tammemagi, H.Y.; Kerford, P.S.; Requeima, J.C.; Temple, C.A.

1980-02-01

A geological reconnaissance survey was carried out of the Lac du Bonnet batholith, southeastern Manitoba, as part of the concept verification phase of the nuclear fuel waste disposal program for Canada. This report summarizes available geological information, presents the results of field mapping and discusses the geochemical analyses of rock samples. The geological and structural aspects of the batholith are described as well as its regional setting and possible genesis. (auth)

Kinetic Analysis of Lactose Exchange in Proteoliposomes Reconstituted with Purified lac Permease

NARCIS (Netherlands)

Lolkema, Julius S.; Carrasco, Nancy; Kaback, H. Ronald

1991-01-01

Lactose exchange catalyzed by purified lac permease reconstituted into proteoliposomes was analyzed with unequal concentrations of lactose on either side of the membrane and at low pH so as to prevent equilibration of the two pools. Exchange with external concentrations below 1.0 mM is a

Sexual competion of irradiated males of the cowpea weevil, callosobruchus maculatus (F.)

International Nuclear Information System (INIS)

Ahmed, M.Y.Y.; Younes, M.W.F.

1981-01-01

When unmated males of Callosobruchus maculatus were irradiated with 7.5 or 10 Krad and confined with normal females, 97.90 and 89.32%, respectively, of the eggs did not hatch, compared with 15.49% infertility of the control eggs. Increasing the dose to 12.5 or 15 Krad induced 99.44 and 100%, respectively, sterility in the irradiated (I) males. When males treated with 7.5, 10 or 12.5 Krad were confined with unirradiated (U) males and females (1:1:1 ratio), infertility of the resulting eggs were 60.06, 67.96 and 69.04%, respectively. The competitiveness values of irradiated males with the above doses and ratio were 1.2, 1.6 and 1.8. Thus, males treated with substerilizing doses (7.5, 10 or 12.5 Krad) competed favourably with (U) males, and males treated with the sterilizing dose (15 Krad) were also fully competitive with (U) males. These results indicated that irradiation with 15 Krad, a sterilizing dose, did not decrease sexual competitiveness of irradiated males. (author)

Probing BL Lac and Cluster Evolution via a Wide-angle, Deep X-ray Selected Sample

Science.gov (United States)

Perlman, E.; Jones, L.; White, N.; Angelini, L.; Giommi, P.; McHardy, I.; Wegner, G.

1994-12-01

The WARPS survey (Wide-Angle ROSAT Pointed Survey) has been constructed from the archive of all public ROSAT PSPC observations, and is a subset of the WGACAT catalog. WARPS will include a complete sample of >= 100 BL Lacs at F_x >= 10(-13) erg s(-1) cm(-2) . A second selection technique will identify ~ 100 clusters at 0.15 = 0.304 +/- 0.062 for XBLs but = 0.60 +/- 0.05 for RBLs. Models of the X-ray luminosity function (XLF) are also poorly constrained. WARPS will allow us to compute an accurate XLF, decreasing the error bars above by over a factor of two. We will also test for low-luminosity BL Lacs, whose non-thermal nuclear sources are dim compared to the host galaxy. Browne and Marcha (1993) claim the EMSS missed most of these objects and is incomplete. If their predictions are correct, 20-40% of the BL Lacs we find will fall in this category, enabling us to probe the evolution and internal workings of BL Lacs at lower luminosities than ever before. By removing likely QSOs before optical spectroscopy, WARPS requires only modest amounts of telescope time. It will extend measurement of the cluster XLF both to higher redshifts (z>0.5) and lower luminosities (LX<1x10(44) erg s(-1) ) than previous measurements, confirming or rejecting the 3sigma detection of negative evolution found in the EMSS, and constraining Cold Dark Matter cosmologies. Faint NELGs are a recently discovered major contributor to the X-ray background. They are a mixture of Sy2s, starbursts and galaxies of unknown type. Detailed classification and evolution of their XLF will be determined for the first time.

The SOS-LUX-LAC-FLUORO-Toxicity-test on the International Space Station (ISS).

Science.gov (United States)

Rabbow, E; Rettberg, P; Baumstark-Khan, C; Horneck, G

2003-01-01

In the 21st century, an increasing number of astronauts will visit the International Space Station (ISS) for prolonged times. Therefore it is of utmost importance to provide necessary basic knowledge concerning risks to their health and their ability to work on the station and during extravehicular activities (EVA) in free space. It is the aim of one experiment of the German project TRIPLE-LUX (to be flown on the ISS) to provide an estimation of health risk resulting from exposure of the astronauts to the radiation in space inside the station as well as during extravehicular activities on one hand, and of exposure of astronauts to unavoidable or as yet unknown ISS-environmental genotoxic substances on the other. The project will (i) provide increased knowledge of the biological action of space radiation and enzymatic repair of DNA damage, (ii) uncover cellular mechanisms of synergistic interaction of microgravity and space radiation and (iii) examine the space craft milieu with highly specific biosensors. For these investigations, the bacterial biosensor SOS-LUX-LAC-FLUORO-Toxicity-test will be used, combining the SOS-LUX-Test invented at DLR Germany (Patent) with the commercially available LAC-FLUORO-Test. The SOS-LUX-Test comprises genetically modified bacteria transformed with the pBR322-derived plasmid pPLS-1. This plasmid carries the promoterless lux operon of Photobacterium leiognathi as a reporter element under control of the DNA-damage dependent SOS promoter of ColD as sensor element. This system reacts to radiation and other agents that induce DNA damages with a dose dependent measurable emission of bioluminescence of the transformed bacteria. The analogous LAC-FLUORO-Test has been developed for the detection of cellular responses to cytotoxins. It is based on the constitutive expression of green fluorescent protein (GFP) mediated by the bacterial protein expression vector pGFPuv (Clontech, Palo Alto, USA). In response to cytotoxic agents, this system

Determination of some heavy metals in oreochromis niloticus, clarias gariepinus and synodontis spp from the coastal water of Ondo State, Nigeria

International Nuclear Information System (INIS)

Asaolu, S.S.

2002-01-01

Some heavy metals (Pb, Ni, Fe, Cu, Zn, Cd, Co, Mn, and Cr) were determined in Oreochromis niloticus, Clarias graiepinus and Synodontis spp obtained from the coastal water of Ondo State. All metals examined and detected in all fish samples. Iron, manganese and cadmium were found to be the most abundant metals in the fish samples with an average values of 35.8, 31.3, and 12.5 mg kg-1 respectively. Except for manganese, iron and cadmium, Syndrontis spp has the highest concentration for virtually all the metals under examination. (author)

Distinct roles of two ceramide synthases, CaLag1p and CaLac1p, in the morphogenesis of Candida albicans

DEFF Research Database (Denmark)

Cheon, Seon Ah; Bal, Jyotiranjan; Song, Yunkyoung

2012-01-01

p) and Lac1p (CaLac1p) are functionally distinct. Lack of CaLag1p, but not CaLac1p, caused severe defects in the growth and hyphal morphogenesis of C. albicans. Deletion of CaLAG1 decreased expression of the hypha-specific HWP1 and ECE1 genes. Moreover, overexpression of CaLAG1 induced pseudohyphal...... growth in this organism under non-hypha-inducing conditions, suggesting that CaLag1p is necessary for relaying signals to induce hypha-specific gene expression. Analysis of ceramide and sphingolipid composition revealed that CaLag1p predominantly synthesizes ceramides with C24:0/C26:0 fatty acid moieties...

Optical polarimetry of quasi-stellar and BL Lac objects

International Nuclear Information System (INIS)

Wills, D.; Wills, B.J.; Breger, M.; Hsu, J.

1980-01-01

We report observations of 39 extragalactic objects, using a new polarimeter at McDonald Observatory. Most of the observations were made in January and June 1980. Some new BL Lac objects were found, and some of the previously known members of this class were also observed. Polarization exceeding 3--4 times the formal rms uncertainties was found in about ten QSO's. Rapid changes of polarization and/or position angle occurred in some of the BL Lacertae objects, usually with <0.1-mag change in the total light

Quarantine treatment by gamma radiation for different development stages of Callosobruchus maculatus in bean Vigna sinensis

International Nuclear Information System (INIS)

Arthur, Valter; Machi, André R.; Franco, Suely S.H.

2017-01-01

The loss of stored grain caused by insects generates a problem of economic order of importance, due to concern about the increased supply of food for the world population is expanding. Associated with this fact, there is the problem of nutritional deficiency due to lack of protein, especially for the less privileged populations. The use of ionizing radiation in grains and products stored without a doubt can solve the problem of the losses in these products, since it does not induce resistance to insects and leaves no toxic residue in the products, and is considered an effective and safe method. The aim of the experiment was to determine the effect of ionizing radiation from cobalt-60 as a quarantine treatment for the different stages of development of Callosobruchus maculatus (Fabr., 1972) (Coleóptera, Chysomilidae) in bean Vigna sinensis. The experiment was conducted in the laboratory of Radiobiology and Environment CENA/USP, Piracicaba, SP, Brazil. Bean samples infested with eggs, larvae, pre-pupae and pupae C. maculatus, the experiment consisted of 4 replicates for each stage of the insect's life cycle, and each repetition consisted of 20 individuals (eggs, larvae, pre-pupae and pupae), a total of 200 subjects per treatment which were irradiated with doses of 0 (control), 25, 50, 75 and 100 Gy, a source of cobalt-60, Gammabeam-650 type, in a rate dose of 1.3 kGy / h. The experiment was conducted in a room with a relative of 25 ± 2 ° C temperature and humidity of 70 ± 5%. After 35 days of irradiation process were carried out evaluations of the number of insects emerged in each repetition within the treatments. From the results obtained it was concluded that the dose lethal to eggs and larvae was 25 Gy, while for pre-pupae was 50 Gy, to pupae 100 Gy was not sufficient to control the adult emergence. (author)

Quarantine treatment by gamma radiation for different development stages of Callosobruchus maculatus in bean Vigna sinensis

Energy Technology Data Exchange (ETDEWEB)

Arthur, Valter; Machi, André R.; Franco, Suely S.H., E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil). laboratório de Radiobiologia e Ambiente; Fontes, Lucia da Silva, E-mail: lsfontes@uol.com.br [Universidade Federal do Piauí (UFPI), Teresina, PI (Brazil). Dept. de Biologia; Harder, Márcia N.C., E-mail: marcia.harder@fatec.sp.gov.br [Faculdade de Tecnologia de Piracicaba (FATEC), SP (Brazil). Dep. Roque Trevisan; Rossi, Rodrigo S.; Arthur, Paula B.; Franco, José G., E-mail: paula.arthur@hotmail.com, E-mail: zegilmar60@gamil.com, E-mail: gilmita@uol.com.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

2017-07-01

The loss of stored grain caused by insects generates a problem of economic order of importance, due to concern about the increased supply of food for the world population is expanding. Associated with this fact, there is the problem of nutritional deficiency due to lack of protein, especially for the less privileged populations. The use of ionizing radiation in grains and products stored without a doubt can solve the problem of the losses in these products, since it does not induce resistance to insects and leaves no toxic residue in the products, and is considered an effective and safe method. The aim of the experiment was to determine the effect of ionizing radiation from cobalt-60 as a quarantine treatment for the different stages of development of Callosobruchus maculatus (Fabr., 1972) (Coleóptera, Chysomilidae) in bean Vigna sinensis. The experiment was conducted in the laboratory of Radiobiology and Environment CENA/USP, Piracicaba, SP, Brazil. Bean samples infested with eggs, larvae, pre-pupae and pupae C. maculatus, the experiment consisted of 4 replicates for each stage of the insect's life cycle, and each repetition consisted of 20 individuals (eggs, larvae, pre-pupae and pupae), a total of 200 subjects per treatment which were irradiated with doses of 0 (control), 25, 50, 75 and 100 Gy, a source of cobalt-60, Gammabeam-650 type, in a rate dose of 1.3 kGy / h. The experiment was conducted in a room with a relative of 25 ± 2 ° C temperature and humidity of 70 ± 5%. After 35 days of irradiation process were carried out evaluations of the number of insects emerged in each repetition within the treatments. From the results obtained it was concluded that the dose lethal to eggs and larvae was 25 Gy, while for pre-pupae was 50 Gy, to pupae 100 Gy was not sufficient to control the adult emergence. (author)

Purified reconstituted lac carrier protein from Escherichia coli is fully functional.

Science.gov (United States)

Viitanen, P; Garcia, M L; Kaback, H R

1984-03-01

Proteoliposomes reconstituted with lac carrier protein purified from the plasma membrane of Escherichia coli catalyze each of the translocation reactions typical of the beta-galactoside transport system (i.e., active transport, counterflow, facilitated influx and efflux) with turnover numbers and apparent Km values comparable to those observed in right-side-out membrane vesicles. Furthermore, detailed kinetic studies show that the reconstituted system exhibits properties analogous to those observed in membrane vesicles. Imposition of a membrane potential (delta psi, interior negative) causes a marked decrease in apparent Km (by a factor of 7 to 10) with a smaller increase in Vmax (approximately equal to 3-fold). At submaximal values of delta psi, the reconstituted carrier exhibits biphasic kinetics, with one component manifesting the kinetic parameters of active transport and the other exhibiting the characteristics of facilitated diffusion. Finally, at low lactose concentrations, the initial velocity of influx varies linearly with the square of the proton electro-chemical gradient. The results provide quantitative support for the contention that a single polypeptide species, the product of the lac y gene, is responsible for each of the transport reactions typical of the beta-galactoside transport system.

The extent of co-metabolism of glucose and galactose by L. lactis changes with the expression of the lacSZ operon from Streptococcus thermophilus

DEFF Research Database (Denmark)

Solem, Christian; Købmann, Brian Jensen; Jensen, Peter Ruhdal

2008-01-01

The lactose transporter and β-galactosidase from Streptococcus thermophilus, encoded by the lacSZ operon, were introduced into the lactose-negative strain Lactococcus lactis MG1363 and the expression of the lacSZ operon was modulated by substitution of the native promoter with randomized synthetic...... promoters. A series of strains with various expression levels of lacSZ were examined for their fermentation of lactose. Strains with a high expression level were found to metabolize lactose in a similar manner to S. thermophilus, i.e. the galactose moiety of lactose was excreted to the growth medium...... and only glucose was metabolized in glycolysis. Interestingly, strains with low expression of the operon showed a mixed acid metabolism and co-metabolism of galactose and glucose. The lactose flux increased gradually with increasing expression of the lacSZ operon until an optimum was observed...

Dissemination in athymic nude mice of lacZ transfected small cell lung cancer cells identified by X-gal staining

DEFF Research Database (Denmark)

Rømer, M U; Christiansen, J; Brünner, N

1995-01-01

The small cell lung cancer cell lines GLC-2 and DMS 456 were genetically labeled with the lacZ gene and examined for invasive and metastatic potential in META/Bom nude mice. The lacZ gene encodes the enzyme beta-D- galactosidase, and cells expressing this enzyme were identified by staining...... with the chromogenic substrate X-gal. lacZ expressing cells were investigated after subcutaneous (s.c.) inoculation and intravenous (i.v.) injection. The X-gal detection of beta-D-galactosidase activity proved to be a rapid and easy means for specific and highly sensitive identification of metastases. All primary s.......c. tumors stained by X-gal. The primary tumors of GLC-2 regularly demonstrated local invasive growth and produced multiple metastases in several organs. In contrast, primary DMS 456 tumors only occasionally demonstrated local invasion and very rarely generated secondary foci. No experimental metastases were...

Absorption in the spectra of quasi stellar objects and BL Lac objects

International Nuclear Information System (INIS)

Perry, J.J.; Burbidge, E.M.; Burbidge, G.R.

1978-06-01

An extensive review is given of the observations of absorption in the spectra of QSOs and BL Lac objects. In Table Ia we summarize all of the information available up to May 1, 1978 on objects which show absorption. Following discussion of the observations in Section II, possible interpretations are critically discussed. (orig.) [de

Tunable Control of an Escherichia coli Expression System for the Overproduction of Membrane Proteins by Titrated Expression of a Mutant lac Repressor.

Science.gov (United States)

Kim, Seong Keun; Lee, Dae-Hee; Kim, Oh Cheol; Kim, Jihyun F; Yoon, Sung Ho

2017-09-15

Most inducible expression systems suffer from growth defects, leaky basal induction, and inhomogeneous expression levels within a host cell population. These difficulties are most prominent with the overproduction of membrane proteins that are toxic to host cells. Here, we developed an Escherichia coli inducible expression system for membrane protein production based on titrated expression of a mutant lac repressor (mLacI). Performance of the mLacI inducible system was evaluated in conjunction with commonly used lac operator-based expression vectors using a T7 or tac promoter. Remarkably, expression of a target gene can be titrated by the dose-dependent addition of l-rhamnose, and the expression levels were homogeneous in the cell population. The developed system was successfully applied to overexpress three membrane proteins that were otherwise difficult to produce in E. coli. This gene expression control system can be easily applied to a broad range of existing protein expression systems and should be useful in constructing genetic circuits that require precise output signals.

Food-grade host/vector expression system for Lactobacillus casei based on complementation of plasmid-associated phospho-beta-galactosidase gene lacG.

Science.gov (United States)

Takala, T M; Saris, P E J; Tynkkynen, S S H

2003-01-01

A new food-grade host/vector system for Lactobacillus casei based on lactose selection was constructed. The wild-type non-starter host Lb. casei strain E utilizes lactose via a plasmid-encoded phosphotransferase system. For food-grade cloning, a stable lactose-deficient mutant was constructed by deleting a 141-bp fragment from the phospho-beta-galactosidase gene lacG via gene replacement. The deletion resulted in an inactive phospho-beta-galactosidase enzyme with an internal in-frame deletion of 47 amino acids. A complementation plasmid was constructed containing a replicon from Lactococcus lactis, the lacG gene from Lb. casei, and the constitutive promoter of pepR for lacG expression from Lb. rhamnosus. The expression of the lacG gene from the resulting food-grade plasmid pLEB600 restored the ability of the lactose-negative mutant strain to grow on lactose to the wild-type level. The vector pLEB600 was used for expression of the proline iminopeptidase gene pepI from Lb. helveticus in Lb. casei. The results show that the food-grade expression system reported in this paper can be used for expression of foreign genes in Lb. casei.

Computing Optical Variable Periods of BL Lac Object S5 0716+714 ...

Indian Academy of Sciences (India)

2016-01-27

Jan 27, 2016 ... From a large volume of literature, we have collected effective observation of BL Lac object S5 0716+714 in the optical band, and constructed its long-term light curve from 1994 to 2006 AD. The light curve shows that S5 0716+714 is very active and exhibits very complicated non-sinusoidal variations.

ABNORMALITAS MORFOLOGIS BENIH IKAN LELE AFRIKA (Clarias gariepinus STRAIN MUTIARA

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Bambang Iswanto

2015-12-01

Full Text Available Ikan lele Mutiara merupakan strain baru ikan lele Afrika (Clarias gariepinus hasil pemuliaan yang memiliki keunggulan-keunggulan karakteristik budidaya, terutama pertumbuhan. Selain karakteristik budidayanya, karakteristik morfologis ikan lele Mutiara juga perlu dieksplorasi. Salah satu aspek morfologi yang perlu dieksplorasi tersebut adalah abnormalitas morfologis benihnya. Penelitian ini bertujuan untuk mengetahui abnormalitas morfologis benih ikan lele Mutiara dibandingkan dengan benih strain-strain ikan lele Afrika lain yang digunakan dalam kegiatan budidaya di Indonesia, yakni ikan lele Sangkuriang, Dumbo, Sukhoi, Burma, Paiton, Phyton dan Masamo. Karakteristik yang diamati adalah abnormalitas bentuk morfologis (deformitas dan fluktuasi asimetri sirip dada dan sirip perut. Hasil penelitian ini menunjukkan bahwa tingkat deformitas (4,00% dan fluktuasi asimetri (sirip dada 0,14 dan sirip perut 0,02 benih ikan lele Mutiara lebih rendah daripada benih-benih ikan lele Sangkuriang, Dumbo, Sukhoi, Burma, Paiton, Phyton dan Masamo (deformitas berkisar 6,00-42,00%, fluktuasi asimetri sirip dada berkisar 0,30-0,68 dan sirip perut berkisar 0,12-0,62. Hasil tersebut menunjukkan bahwa bentuk morfologis benih ikan lele Mutiara lebih normal daripada benih-benih ikan lele Sangkuriang, Dumbo, Sukhoi, Burma, Paiton, Phyton dan Masamo. Hal tersebut mengindikasikan bahwa mutu dan keragaman genetis ikan lele Mutiara lebih tinggi daripada strain-strain ikan lele Afrika lain yang digunakan dalam kegiatan budidaya di Indonesia tersebut.

Evaluation of the seed oil of three citrus species, for the control of the bean beetle, callosobruchus maculatus (F) (coleoptera: bruchidae)

International Nuclear Information System (INIS)

Ogunleye, R.F.

2009-01-01

On application of the seed oil of ripe and unripe fruits of Citrus sinensis, C. paradisi and C. aurantifolia to the cowpea bruchid, Callosobruchus maculatus (F) for three days, a dose of 0.5 ml of C. sinensis gave, significantly, high mortality rate upto 85%. In case of C. aurantifolia, mortality ranged from 75% to 100%. Same least dosage of seed oil of ripe C. paradissi produced 58.8% to 100% mortality, whereas, except the dose of 0.5 ml, all the other treatments of unripe C. paradissi resulted in 100% mortality after 24 h. (author)

Feeding ω-3 PUFA enriched rotifers to Galaxias maculatus (Jenyns, 1842 larvae reared at different salinity conditions: effects on growth parameters, survival and fatty acids profile

Directory of Open Access Journals (Sweden)

Patricio Dantagnan

2013-07-01

Full Text Available Despite the well known importance of ω-3 polyunsaturated fatty acids (PUFA in marine and freshwater fish larvae, there are few studies on how essential fatty acid requirements and composition on whole body can be altered by changes in water salinity. The present study aimed to determine the effect of salinity on ω-3 PUFA requirements, larval growth survival and fatty acid composition of Galaxias maculatus larvae cultured at two different salinities (0 and 15 g L-1 for 20 days while fed rotifers containing two different levels of ω-3 PUFA (1.87 and 3.16%. The results denoted a marked difference in ω-3 PUFA requirements and in the pattern of fatty acid deposition in the whole body of larvae reared at different salinities, depending of ω-3 PUFA in diets. Thus, to improve growth and survival larvae of G. maculatus reared at 0 g L-1 require higher levels of ω-3 PUFA, principally 18:3 ω-3. Larvae reared at salinities of 15 g L-1 require low levels of ω-3 PUFA for optimal survival, especially 18:3 ω-3. Eicosapentaenoic acid and docosahexaenoic acid content in the whole body of larvae was also affected by water salinity.

Using the Markov chain Monte Carlo method to study the physical properties of GeV-TeV BL Lac objects

Science.gov (United States)

Qin, Longhua; Wang, Jiancheng; Yang, Chuyuan; Yuan, Zunli; Mao, Jirong; Kang, Shiju

2018-01-01

We fit the spectral energy distributions (SEDs) of 46 GeV-TeV BL Lac objects in the frame of leptonic one-zone synchrotron self-Compton (SSC) model and investigate the physical properties of these objects. We use the Markov chain Monte Carlo (MCMC) method to obtain the basic parameters, such as magnetic field (B), the break energy of the relativistic electron distribution (γ ^' }b), and the electron energy spectral index. Based on the modeling results, we support the following scenarios for GeV-TeV BL Lac objects. (1) Some sources have large Doppler factors, implying other radiation mechanism should be considered. (2) Compared with flat spectrum quasars (FSRQs), GeV-TeV BL Lac objects have weaker magnetic fields and larger Doppler factors, which cause the ineffective cooling and shift the SEDs to higher bands. Their jet powers are around 4.0 × 1045 erg s-1, compared with radiation power, 5.0 × 1042 erg s-1, indicating that only a small fraction of jet power is transformed into the emission power. (3) For some BL Lacs with large Doppler factors, their jet components could have two substructures, e.g., the fast core and the slow sheath. For most GeV-TeV BL Lacs, Kelvin-Helmholtz instabilities are suppressed by their higher magnetic fields, leading to micro-variability or intro-day variability in the optical bands. (4) Combined with a sample of FSRQs, an anti-correlation between the peak luminosity, Lpk, and the peak frequency, νpk, is obtained, favoring the blazar sequence scenario. In addition, an anti-correlation between the jet power, Pjet, and the break Lorentz factor, γb, also supports the blazar sequence.

Selection of lactic acid bacteria as a probiotic and evaluated its performance on gnotobiotic catfish Clarias sp.

Directory of Open Access Journals (Sweden)

Enita Romasni Turnip

2018-05-01

Full Text Available ABSTRACT This study aimed to select lactic acid bacteria (LAB as a potential probiotic that producing anti‒microbial compounds in order to treat motile aeromonads septicemia diseases caused by Aeromonas hydrophila on catfish Clarias sp. and evaluated its performance on gnotobiotic catfish. The in vitro assay was done to select several LAB isolates based on antagonistic activity against pathogenic bacteria. The selected isolate was tested in vivo to observe their ability to improve growth performances of catfish. The study was conducted with five treatments consists of K‒ (normal catfish without addition probiotic, without challenge test, K+ (normal catfish without addition of probiotic, with challenge test, Np (normal catfish with addition of probiotic and challenge test, G (gnoto catfish without addition of probiotic, with challenge test, and Gp (gnoto catfish with addition of probiotic and challenge test. The results showed that the addition of Pediococcus pentosaceus E2211 as selected probiotic could increase survival rate, specific growth rate, and immune response towards infection of A. hydrophila. The best survival rate after challenge test was obtained in Np and Gp treatments (88.46%, followed by G treatment (65.38%, while the K+ was only 53.84%. The conclusion of this study was P. pentosaceus E2211 potentially used as a probiotic candidate for normal and gnotobiotic catfish. The presence of normal microflora with P. pentosaceus E2211 in Np treatment showed the best probiotic performance with daily growth rate 3.28%, feed conversion ratio 1.79, and total intestinal bacteria reached 108 CFU/mL significantly different from other treatments (P<0.05.Keywords: Aeromonas hydrophila, catfish, LAB, probiotic, screening  ABSTRAKTujuan penelitian ini adalah menyeleksi bakteri asam laktat (BAL sebagai probiotik potensial penghasil senyawa antimikrob guna menanggulangi penyakit motile aeromonad septicemia akibat Aeromonas hydrophila pada ikan

Discovery of Intermediates of lacZ β-Galactosidase Catalyzed Hydrolysis Using dDNP NMR

DEFF Research Database (Denmark)

Kjeldsen, Christian; Ardenkjær-Larsen, Jan Henrik; Duus, Jens Ø.

2018-01-01

Using dissolution dynamic nuclear polarization, the sensitivity of single scan solution state 13C NMR can be improved up to 4 orders of magnitude. In this study, the enzyme lacZ β-galactosidase from Escherichia coli was subjected to hyperpolarized substrate, and previously unknown reaction...

Discovery of Intermediates of lacZ beta-Galactosidase Catalyzed Hydrolysis Using dDNP NMR

DEFF Research Database (Denmark)

Kjeldsen, Christian; Ardenkjær-Larsen, Jan Henrik; Duus, Jens Øllgaard

2018-01-01

Using dissolution dynamic nuclear polarization, the sensitivity of single scan solution state C-13 NMR can be improved up to 4 orders of magnitude. In this study, the enzyme lacZ beta-galactosidase from Escherichia coli was subjected to hyperpolarized substrate, and previously unknown reaction...

lacZ transduced human breast cancer xenografts as an in vivo model for the study of invasion and metastasis

DEFF Research Database (Denmark)

Brünner, N; Thompson, E W; Spang-Thomsen, M

1992-01-01

in the animals by usual histological procedures would require extensive sectioning of the whole animal. To overcome this problem, we transduced human breast cancer cells with a replication-defective Moloney murine leukaemia retroviral vector (M-MuLV) containing both neoR (neomycin resistance) and lacZ genes...... but not the surrounding mouse tissue on either whole tissue blocks or histological sections. The staining procedure was highly sensitive, allowing detection of microfoci of human cancer cells, and quantitative estimation of the metastatic capacity of the cells. These results indicate that lacZ transduction of human...

Stress in African catfish (Clarias gariepinus) following overland transportation.

Science.gov (United States)

Manuel, Remy; Boerrigter, Jeroen; Roques, Jonathan; van der Heul, Jan; van den Bos, Ruud; Flik, Gert; van de Vis, Hans

2014-02-01

Of the many stressors in aquaculture, transportation of fish has remained poorly studied. The objective of this study was therefore to assess the effects of a (simulated) commercial transportation on stress physiology of market-size African catfish (Clarias gariepinus). Catfish weighing approximately 1.25 kg were returned to the farm after 3 h of truck-transportation, and stress-related parameters were measured for up to 72 h following return. Recovery from transportation was assessed through blood samples measuring plasma cortisol, glucose and non-esterified fatty acids (NEFA) and gill histology. Also, the number of skin lesions was compared before and after transport. Pre-transport handling and sorting elevated plasma cortisol levels compared to unhandled animals (before fasting). Plasma cortisol levels were further increased due to transportation. In control fish, plasma cortisol levels returned to baseline values within 6 h, whereas it took 48 h to reach baseline values in transported catfish. Plasma glucose and NEFA levels remained stable and were similar across all groups. Transported catfish did not, on average, have more skin lesions than the handling group, but the number of skin lesions had increased compared to unhandled animals. The macroscopic condition of the gills was similar in control, transported and unhandled catfish; however, light microscopy and immunohistochemistry revealed atypical morphology and chloride cell migration normally associated with adverse water conditions. From our data, we conclude that transportation may be considered a strong stressor to catfish that may add to other stressors and thus inflict upon the welfare of the fish.

The genus Hypostomus Lacépède, 1803, and its Surinam representatives (Siluriformes, Loricariidae)

NARCIS (Netherlands)

Boeseman, M.

1968-01-01

CONTENTS Introduction................... 3 The generic name................. 4 The type species of Hypostomus Lacépède.......... 6 The identity of Acipenser plecostomus Linnaeus........ 9 The distribution and habitats of the Surinam species........ 12 The relationship of the Surinam

Performance of Clarias gariepinus Fed Dried Brewer's Yeast (Saccharomyces cerevisiae) Slurry in Replacement for Soybean Meal.

Science.gov (United States)

Solomon, Shola Gabriel; Ataguba, Gabriel Arome; Itodo, Gabriel Enemona

2017-01-01

Following disparity of earlier results, this study tested the performance of African catfish Clarias gariepinus fed dried brewer's yeast slurry meal (DBYM) based diets. Fingerlings of C. gariepinus with pooled mean initial weight of 1.58 ± 0.01 g were stocked in hapas (1 m × 1 m × 1 m) immersed in an earthen pond at a density of 15 fish per cage. Five diets with increasing substitution of soybean meal with 25%, 50%, 75%, and 100% of dried brewer's yeast and a control without dried brewer's yeast (0% substitution) were evaluated for 8 weeks. Palatability of diets reduced with increasing levels of DBYM. Growth and utilization parameters such as weight gain, feed conversion ratio, protein efficiency ratio, and specific growth rate differed significantly ( p meal with DBYM in C. gariepinus feed is between 1% and 14% of dry matter.

Atividade inseticida de óleos essenciais e fixos sobre Callosobruchus maculatus (FABR., 1775 (Coleoptera: Bruchidae em grãos de caupi [Vigna unguiculata (L. WALP.] Insecticide activity of essential and fixed oils in Callosobruchus maculatus (FABR., 1775 (Coleoptera: Bruchidae in cowpea grains [Vigna unguiculata (L. WALP.

Directory of Open Access Journals (Sweden)

Adriana Carla Ribeiro Lopes Pereira

2008-06-01

Full Text Available O caruncho, Callosobruchus maculatus (Fabr., é considerado a praga mais importante do caupi, Vigna unguiculata (L. Walp., armazenado em regiões tropicais e subtropicais. Visando minimizar os efeitos indesejáveis dos inseticidas químicos sintéticos, o controle dessa praga com óleos de origem vegetal vem se constituindo numa alternativa promissora, de baixo custo e segura para os aplicadores e consumidores. Foram testados os óleos essenciais [(Cymbopogon martini (Roxb. J.F. Watson], Piper aduncum L., Piper hispidinervum C.DC., Melaleuca sp., Lippia gracillis Shauer e fixos (Helianthus annuus L, Sesamum indicum L, Gossypium hirsutum L., Glycine max (L. Merr. e Caryocar brasiliense Camb., em grãos de caupi, cv. Sempre Verde. Os óleos foram utilizados nas concentrações 10, 20, 30, 40 e 50mL/20g, correspondendo a 0,5, 1,0, 1,5, 2,0 e 2,5 L/t e impregnados aos grãos no interior de recipientes de plástico, com auxílio de pipetador automático e agitados manualmente durante dois minutos. Parcelas de 20g de caupi foram infestadas com oito fêmeas de C. maculatus, com 0 a 48 h de idade. Cada óleo foi testado, separadamente, em delineamento inteiramente casualisado com seis repetições. Os óleos essenciais de C. martini, P. aduncum e L. gracillis causaram 100% de mortalidade em todas as concentrações, P. hispidinervum a partir de 1,5 L/t e Melaleuca sp. nas concentrações de 2,0 e 2,5 L/t. A redução do número de ovos viáveis e de insetos emergidos foi de 100% para todos os óleos essenciais, exceto Melaleuca sp. Por outro lado, os óleos fixos, apesar de apresentarem baixa mortalidade em todas as concentrações testadas, reduziram em praticamente 100% o número de ovos viáveis e de insetos emergidos.The weevil Callosobruchus maculatus (Fabr. is considered the most important pest of cowpea, Vigna unguiculata (L. Walp., stored in tropical and subtropical regions. Focusing to minimize the undesired effects of synthetic chemical

The Accumulation and Retention of Zine-65 and Cobalt-60 by The Fresh Water Fish CLARIAS LAZERA

International Nuclear Information System (INIS)

Abdel Malik, W.E.Y.; Ibrahim, A.S.; Badawy, S.A.

2003-01-01

Some parameters affecting the accumulation and retention of 65 Zn and 60 Co radionuclides by the fresh water fish CLARIAS LAZERA from the contaminated filtered Ismail ia Canal water(FICW) have been investigated. It has been observed that the accumulated activity (KBq/g) increased with increasing exposure time with the contaminated FICW. This kind of bony fish has been shown to accumulate 65 Zn > 60 Co. The increase of the studied radionuclide carrier concentration in the canal water increased the fish uptake of both radionuclides. The increase of ph of the FICW decreased the accumulated activity by the fish. On the other hand, the retention of those radionuclides by this fish was investigated. It was possible from this study to give preliminary data for the calculation of the radiation dose that might be delivered to man eating the contaminated fish

Observations of low and intermediate-frequency-peaked BL Lacs above 100 GeV with VERITAS

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Errando M.

2013-12-01

Full Text Available Most of the ~ 50 blazars detected to date at TeV energies (E > 0.1 TeV are high-frequency-peaked BL Lacs (HBLs. Only a handful episodic detections of low- and intermediate-frequency-peaked BL Lacs (LBL/IBLs, with synchrotron peak frequencies in the infrared and optical regime have been reported by ground-based gamma-ray telescopes, typically during high-flux states. The VERITAS array located in southern Arizona has observed five known TeV LBL/IBLs since 2009: 3C 66A, WComae, PKS 1424+240, S5 0716+714 and BL Lacertae, with exposures of 5-10 hours/year, which so far resulted in the detection of a bright, sub-hour timescale gamma-ray flare of BL Lacertae in June 2011. We also report the detection and characterization of two new IBLs: VER J0521+211 and B2 1215+30.

Dynamical Black Hole Masses of BL Lac Objects from the Sloan Digital Sky Survey

NARCIS (Netherlands)

Plotkin, Richard M.; Markoff, Sera; Trager, Scott C.; Anderson, Scott F.

2012-01-01

We measure black hole masses for 71 BL Lac objects from the Sloan Digital Sky Survey (SDSS) with redshifts out to z ∼ 0.4. We perform spectral decompositions of their nuclei from their host galaxies and measure their stellar velocity dispersions. Black hole masses are then derived from the black

The LAC Test: A New Look at Auditory Conceptualization and Literacy Development K-12.

Science.gov (United States)

Lindamood, Charles; And Others

The Lindamood Auditory Conceptualization (LAC) Test was constructed with the recognition that the process of decoding involves an integration of the auditory, visual, and motor senses. Requiring the manipulation of colored blocks to indicate conceptualization of test patterns spoken by the examiner, subtest 1 entails coding of identity, number,…

Caractérisation des sables et morphologie du fond du lac du ...

African Journals Online (AJOL)

Une analyse sédimentologique et minéralogique réalisée sur un cycle hydrologique entre octobre 2004 et août 2005 a permis d\\'évaluer les charges solides en suspension et de caractériser les sédiments du lac du barrage de Taabo. La concentration moyenne en matières en suspension (12 mg.L-1) et la turbidité ...

Caractérisation des sables et morphologie du fond du lac du ...

African Journals Online (AJOL)

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Une analyse sédimentologique et minéralogique réalisée sur un cycle hydrologique entre octobre 2004 et août 2005 a permis d'évaluer les charges solides en suspension et de caractériser les sédiments du lac du barrage de Taabo. La concentration moyenne en matières en suspension (12 mg.L-1) et la turbidité ...

Effect of the partial NaCl substitution by other chloride salts on the volatile profile during the ripening of dry-cured lacón

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Domínguez, R.

2016-06-01

Full Text Available The influence of three salting treatments (treatment II: 50% NaCl-50% KCl; III: 45% NaCl-25% KCl-20% CaCl2-10% MgCl2; IV: 30% NaCl-50% KCl-15% CaCl2-5% MgCl2 on the formation of volatile compounds throughout the process was studied and compared to those of a control “lacón” (treatment I: 100% NaCl. There was an intense formation of volatile compounds throughout the processing, particularly during the dry-ripening stage. The most abundant chemical family in all the formulations, in the final product was hydrocarbons followed by aldehydes. The total volatile compound release was more intense in the control “lacóns” (1164 AU_106·g-1dry matter than in “lacóns” from formulations II, III and IV (817-891 AUx106·g-1dry matter. The “lacóns” from formulation I showed the highest amounts of aldehydes. The “lacóns” from formulations I and II presented the highest amounts of hydrocarbons. The main conclusion is that the replacement of NaCl produces changes in the volatile profile and could be affect the aroma of “lacón”.Se estudió la influencia de tres tratamientos de salado (tratamiento II: 50 % NaCl-50 % KCl; III: 45 % NaCl-25 % KCl-20 % CaCl2-10 % MgCl2; IV: 30 % NaCl-50 % KCl-15 % CaCl2-5 % MgCl2 en la formación de compuestos volátiles durante la elaboración de lacón, en comparación con un control (tratamiento I: 100 % NaCl. Hubo una intensa formación de compuestos volátiles durante el procesado, principalmente durante la fase de secado-maduración. La familia química más abundante en el producto final fueron los hidrocarbonos, seguidos por los aldehídos. La liberación de volátiles fue más intensa en los lacones control (1164 AU_106·g-1 materia seca que en los otros lacones (817-891 AUx106· g-1 materia seca. Los lacones de la formulación I mostraron las mayores cantidades de aldehídos, y los lacones de las formulaciones I y II presentaron los mayores contenidos de hidrocarburos. La principal conclusi

Du Lac de Geneve au Lac Baikal: deux metropoles en construction

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Guy Mettan

2006-08-01

Full Text Available En apparence, Geneve et Irkutsk n'ont rien en commun. A part une amitie reciproque et la proximite d'un lac, il est difficile de trouver des points communs entre la Suisse francophone, dont Geneve est la ville le plus importante, et la Siberie centrale, dont Irkutsk, est la capitale. Et pourtant les deux regions, malgre les differences de taille, de densite de la population, de climat, d'economie et de traditions culturelles, sont confrontees au meme probleme: elles sont trop petites et trop limitees pour assurer, avec leurs seuls moyens, leur avenir et elles doivent imperativement s'unir a des villes voisines pour renforcer leur statut de metropole regionale et s'imposer face aux regions et aux pays concurrents.C'est ainsi qu'Irkutsk projette de s'unir aux villes voisines d'Angarsk et de Chelekhov pour constituer une megapole au c?ur de la Siberie, tandis qu'a Geneve le debat fait rage pour trouver des solutions a l'exiguite geographique et a l'insuffisance des moyens face aux grandes regions metropolitaines de France, d'Italie et d'Allemagne.Ce debat est propre a toute la Suisse. Malgre sa petitesse, la Suisse est divisee en 26 cantons. Ces unites administratives sont jugees trop couteuses, trop petites, trop lourdes et trop compliquees pour assurer l'avenir economique et meme politique du pays. De nombreux groupes de reflexion proposent donc de reduire ce nombre a 3, 5 ou 10 grandes provinces selon les cas. En Suisse, romande, il y a dix ans, des mouvements politiques ont meme lance l'idee de fusionner les cantons de Vaud (dont Lausanne est la capitale et de Geneve. Mais l'echec a ete fracassant : le peuple des deux cantons a refuse cette option a 80% des voix. On cherche donc d'autres solutions.Les discussions s'orientent desormais autour de la constitution d'une grande metropole lemanique qui regrouperait les deux grandes villes de Geneve et Lausanne et les villes plus petites de Montreux, Vevey, Nyon ainsi que la ville francaise d

KARAKTERISTIK MORFOLOGIS DAN GENETIS IKAN LELE AFRIKA (Clarias gariepinus Burchell, 1822 STRAIN MUTIARA

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Bambang Iswanto

2015-09-01

Full Text Available Ikan lele Mutiara merupakan strain baru ikan lele Afrika Clarias gariepinus hasil pemuliaan yang memiliki keunggulan karakteristik budidaya. Selain karakteristik budidayanya, karakteristik morfologis dan genetis ikan lele Mutiara juga perlu dibandingkan dengan strain yang lain. Penelitian ini bertujuan untuk menganalisis karakteristik morfologis ikan lele Mutiara (melalui uji morfometrik dan meristik, serta karakteristik genetis menggunakan marka DNA mikrosatelit dibandingkan dengan ikan lele Mesir, Paiton, Sangkuriang, dan Dumbo yang merupakan induk-induk pembentuknya. Karakterisasi morfometrik dilakukan melalui pengukuran terhadap 20 karakter, sedangkan karakterisasi meristik dilakukan melalui penghitungan terhadap lima karakter sesuai metode standar karakterisasi biometrik-morfologis ikan lele. Data karakteristik morfometrik dan meristik dievaluasi dengan menggunakan analisis komponen utama. Hasil karakterisasi morfologis menunjukkan bahwa karakteristik morfometrik dan meristik ikan lele Mutiara tidak dapat dibedakan dari ikan lele Mesir, Paiton, Sangkuriang, dan Dumbo. Karakterisasi secara genetis dengan menggunakan empat primer DNA mikrosatelit untuk ikan lele Afrika (Cga01, Cga02, Cga05, dan Cga09 menunjukkan bahwa ikan lele Mutiara memiliki keragaman genetis (jumlah alel dan heterozigositas yang relatif lebih tinggi daripada ikan lele Mesir, Paiton, Sangkuriang, dan Dumbo.

Assessment of Clarias gariepinus as a biological control agent against mosquito larvae.

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Chala, Buze; Erko, Berhanu; Animut, Abebe; Degarege, Abraham; Petros, Beyene

2016-05-31

The emergence and spread of insecticide resistant mosquitoes renewed interest in investigating the use of larvivorous fish as a biological control agent. The potential of Clarias gariepinus fish in controlling Anopheles arabiensis and culicine larvae was assessed under laboratory and semi-field conditions. Small size (15-20 cm) C. gariepinus fish consumed greater number of mosquito larvae than the large size fish (25-40 cm) in the multivariate regression model (β = 13.36, 95 % CI = 4.57, 22.15). The Anopheles larvae consumed was greater in number than the culicines larvae consumed by the fish (β = 12.10, 95 % CI = 3.31, 20.89). The number of larvae consumed was greater during the night hours than during the light hours (β = 30.06, 95 % CI = 21.27, 38.85). Amount of supplementary fish food did not cause significant differences in the number of mosquito larvae consumed by the fish among different groups. C. gariepinus was observed to feed on mosquito larvae under laboratory and semi-field conditions. C. gariepinus fed on the larvae of An. arabiensis and culicines readily. Hence, it can be used as an alternative mosquito control agent in Ethiopia where the breeding habitats are small and localized.

Protein digestibility and ammonia excretion in catfish Clarias gariepinus culture

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Bambang Gunadi

2014-01-01

Full Text Available ABSTRACT A series of experiments was performed to analyze protein digestibility, ammonia excretion, and also heterothropic bacteria and phytoplankton dynamics in the catfish Clarias gariepinus culture. In the digestibility experiment, catfish with an individual initial size of 43.67±0.83 g were stocked into 120 L conical fiberglass tanks at a density of 20 fish per tank. Fish were fed on with commercial diet supplemented with Cr2O3 indicator at a concentration of 1%. In the ammonia excretion experiment, catfish with an individual size of 111.6±9.5 and 40.6±3.4 g, respectively,  were placed into a 10 L chamber filled with 8 L of water. Total ammonia nitrogen (TAN in the chambers were monitored every hour for six consecutive hours. In the bacteria and phytoplankton dynamics experiment, catfish were stocked in the 25 m2 concrete tanks which was divided into two compartments (catfish 10 m2, and heterotrof compartments 15 m2. Catfish with individual size of 42,5±0 g were stocked into the tanks at a density of 100 fish per tank. Water was recirculated from catfish compartments to heterotrophic compartments. Fish were fed with floating feed. Molasses as carbon source for heterotrophic bacteria was applied daily. The experiment was conducted for six weeks. The results showed that the protein digestibility was 61.97±7.24%. Larger fish (size of 111.6 g excreted ammonia at a rate of 0.008±0.003 mg TAN/g fish-weight/hour, which was lower than that of the smaller catfish (size of 40.6 g, i.e. 0.012±0.004 mg TAN/g fish-weight/hour. Keywords: protein digestibility, ammonia excretion, catfish  ABSTRAK Serangkaian penelitian telah dilakukan untuk menganalisis ketercernaan pakan dan protein, ekskresi amonia, serta dinamika bakteri dan fitoplankton pada budidaya ikan lele (Clarias gariepinus. Pada penelitian ketercernaan pakan, ikan lele berukuran 43,67±0,83 g/ekor dipelihara dalam bak fiberglas berbentuk corong berukuran 120 L dengan kepadatan 20

Mutagenicity of ultraviolet A radiation in the lacI transgene in Big Blue mouse embryonic fibroblasts

International Nuclear Information System (INIS)

Kim, Sang-in; Pfeifer, Gerd P.; Besaratinia, Ahmad

2007-01-01

Sunlight ultraviolet A (UVA) irradiation has been implicated in the etiology of human skin cancer. A genotoxic mode of action for UVA radiation has been suggested that involves photosensitization reactions giving rise to promutagenic DNA lesions. We investigated the mutagenicity of UVA in the lacI transgene in Big Blue mouse embryonic fibroblasts. UVA irradiation of these cells at a physiologically relevant dose of 18 J/cm 2 caused a 2.8-fold increase in the lacI mutant frequency relative to control, i.e., 12.12 ± 1.84 versus 4.39 ± 1.99 x 10 -5 (mean ± S.D.). DNA sequencing analysis showed that of 100 UVA-induced mutant plaques and 54 spontaneously arisen control plaques, 97 and 51, respectively, contained a minimum of one mutation along the lacI transgene. The vast majority of both induced- and spontaneous mutations were single base substitutions, although less frequently, there were also single and multiple base deletions and insertions, and tandem base substitutions. Detailed mutation spectrometry analysis revealed that G:C → T:A transversions, the signature mutations of oxidative DNA damage, were significantly induced by UVA irradiation (P -5 ; P < 0.00001). These findings are in complete agreement with those previously observed in the cII transgene of the same model system, and reaffirm the notion that intracellular photosensitization reactions causing promutagenic oxidative DNA damage are involved in UVA genotoxicity

Influência do período de armazenamento do caupi [Vigna unguiculata (L. Walp.], tratado com óleos essenciais e fixos, no controle de Callosobruchus maculatus (Fabricius, 1775 (Coleoptera, Chrysomelidae, Bruchinae Influence of the storage period of cowpea [Vigna unguiculata (L. Walp.] treated with essential and fixed oils, for the control of Callosobruchus maculatus (Fabricius, 1775 (Coleoptera, Chrysomelidae, Bruchinae

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Adriana Carla Ribeiro Lopes Pereira

2009-02-01

Full Text Available Compostos secundários obtidos de plantas podem ser utilizados no controle de Callosobruchus maculatus, como uma tática alternativa potencial aos inseticidas sintéticos. Foram testados óleos essenciais (Cymbopogon martini Roxb., Piper aduncum L., Piper hispidinervum C.DC., Melaleuca sp., Lippia gracillis Shau e fixos (Helianthus annus L., Sesamum indicum L., Gossypium hirsutum L., Glycine max L. e Caryocar brasiliense Camb., na concentração de 50µl/20g, de acordo com estudos anteriores. Grãos de caupi, cv. Sempre Verde, foram impregnados com os óleos, em recipientes de vidro e submetidos à agitação manual por dois minutos. Cada parcela de 20g foi infestada com oito fêmeas de C. maculatus com 0 a 48h de idade, durante quatro dias. Os óleos foram avaliados logo após a impregnação e aos 30, 60, 90 e 120 dias de armazenamento. Na primeira avaliação, todos os óleos essenciais provocaram 100% de mortalidade e para os óleos fixos, a mortalidade variou entre 35% (G. hirsutum e 67,5% (G. max. Com o prolongamento do período de armazenamento, houve um aumento do número de ovos viáveis e de insetos emergidos, exceto para P. aduncum. Em relação aos óleos fixos, S. indicum, G. max, G. hirsutum e C. brasiliense foram os mais eficientes até os 30 dias de armazenamento. Os resultados indicam que os óleos testados na concentração de 50µl/20g apresentam baixo efeito residual, com exceção de P. aduncum, que foi efetivo durante todo o período de armazenamento.The secondary compounds extracted from plants are considered potential alternative to synthetic insecticides in the control of agricultural pests. Essential oils (Cymbopogon martini Roxb., Piper aduncum L., P. hispidinervum C.DC., Melaleuca sp. and Lippia gracillis Shau and fixed oils (Helianthus annus L., Sesamum indicum L., Gossypium hirsutum L., Glycine max L. and Caryocar brasiliense Camb. at the concentration of 50µl/20g were tested according to previous studies. Samples

Mef2c-F10N enhancer driven β-galactosidase (LacZ) and Cre recombinase mice facilitate analyses of gene function and lineage fate in neural crest cells.

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Aoto, Kazushi; Sandell, Lisa L; Butler Tjaden, Naomi E; Yuen, Kobe C; Watt, Kristin E Noack; Black, Brian L; Durnin, Michael; Trainor, Paul A

2015-06-01

Neural crest cells (NCC) comprise a multipotent, migratory stem cell and progenitor population that gives rise to numerous cell and tissue types within a developing embryo, including craniofacial bone and cartilage, neurons and glia of the peripheral nervous system, and melanocytes within the skin. Here we describe two novel stable transgenic mouse lines suitable for lineage tracing and analysis of gene function in NCC. Firstly, using the F10N enhancer of the Mef2c gene (Mef2c-F10N) linked to LacZ, we generated transgenic mice (Mef2c-F10N-LacZ) that express LacZ in the majority, if not all migrating NCC that delaminate from the neural tube. Mef2c-F10N-LacZ then continues to be expressed primarily in neurogenic, gliogenic and melanocytic NCC and their derivatives, but not in ectomesenchymal derivatives. Secondly, we used the same Mef2c-F10N enhancer together with Cre recombinase to generate transgenic mice (Mef2c-F10N-Cre) that can be used to indelibly label, or alter gene function in, migrating NCC and their derivatives. At early stages of development, Mef2c-F10N-LacZ and Mef2c-F10N-Cre label NCC in a pattern similar to Wnt1-Cre mice, with the exception that Mef2c-F10N-LacZ and Mef2c-F10N-Cre specifically label NCC that have delaminated from the neural plate, while premigratory NCC are not labeled. Thus, our Mef2c-F10N-LacZ and Mef2c-F10N-Cre transgenic mice provide new resources for tracing migratory NCC and analyzing gene function in migrating and differentiating NCC independently of NCC formation. Copyright © 2015 Elsevier Inc. All rights reserved.

Local gene regulation details a recognition code within the LacI transcriptional factor family.

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Francisco M Camas

2010-11-01

Full Text Available The specific binding of regulatory proteins to DNA sequences exhibits no clear patterns of association between amino acids (AAs and nucleotides (NTs. This complexity of protein-DNA interactions raises the question of whether a simple set of wide-coverage recognition rules can ever be identified. Here, we analyzed this issue using the extensive LacI family of transcriptional factors (TFs. We searched for recognition patterns by introducing a new approach to phylogenetic footprinting, based on the pervasive presence of local regulation in prokaryotic transcriptional networks. We identified a set of specificity correlations--determined by two AAs of the TFs and two NTs in the binding sites--that is conserved throughout a dominant subgroup within the family regardless of the evolutionary distance, and that act as a relatively consistent recognition code. The proposed rules are confirmed with data of previous experimental studies and by events of convergent evolution in the phylogenetic tree. The presence of a code emphasizes the stable structural context of the LacI family, while defining a precise blueprint to reprogram TF specificity with many practical applications.

Archive of Geosample Data and Information from the University of Minnesota National Lacustrine Core Repository (LacCore)

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National Oceanic and Atmospheric Administration, Department of Commerce — The National Lacustrine Core Repository (LacCore), operated by the University of Minnesota is a partner in the Index to Marine and Lacustrine Geological Samples...

Performance of broodstock and hybrid juvenile of Egyptian and sangkuriang Clarias gariepinus strains

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Putri Zulfania

2016-02-01

Full Text Available ABSTRACT This study was conducted to evaluate reproduction of broodstock and intraspecific hybrid juvenile performance of Egyptian (M and sangkuriang (S strain African catfish Clarias gariepinus at nursery phase. Intraspecific hybridization of African catfish was carried out reciprocally (SM and MS and purebreed (SS and MM, each was with three replicates. Fish spawning was conducted by artificial fertilization, and larvae were reared at 1st, 2nd and 3rd nursery phases, subsequently. The results showed that broodstock performance (male and female of both strains were not significantly different (P>0.05 on all reproduction traits, except female’s gonadosomatic index. Fertilization and hatching rates of all hybrids were not significantly different (P>0.05. MM juvenile had higher growth performances than other juvenile hybrids. Heterosis of total length, standard length, and body weight were varied, whereas the survival showed positive heterosis. SM juvenile showed positive growth heterosis in 3rd nursery phase (total length, standard length, and body weight were 2.61%; 2.16%, and 4.79% respectively. Survival heterosis of MS juvenile (24.20% for total length; 103.13% for standard length and 11.62% body weight was higher than SM juvenile (6.86%; 48.57%, and 3.09% on all nursery phases Keywords: African catfish, intraspecific hybridization, growth, survival, heterosis  ABSTRAK Penelitian ini dilakukan untuk menguji performa reproduksi induk dan benih hasil hibridisasi intraspesifik ikan lele Afrika Clarias gariepinus strain Sangkuriang (S dan Mesir (M pada fase pendederan. Hibridisasi intraspesifik ikan lele Afrika dilakukan secara resiprokal (SM dan MS dan galur murni (SS dan MM masing-masing dengan tiga ulangan. Pemijahan dilakukan secara buatan dan larva yang dihasilkan dipelihara pada fase pendederan pertama, kedua, dan ketiga. Hasil penelitian menunjukkan bahwa performa induk ikan lele jantan dan betina pada kedua strain tidak berbeda

Dietary shift in juvenile coral trout ( Plectropomus maculatus) following coral reef degradation from a flood plume disturbance

Science.gov (United States)

Wen, Colin K. C.; Bonin, Mary C.; Harrison, Hugo B.; Williamson, David H.; Jones, Geoffrey P.

2016-06-01

Acute environmental disturbances impact on habitat quality and resource availability, which can reverberate through trophic levels and become apparent in species' dietary composition. In this study, we observed a distinct dietary shift of newly settled and juvenile coral trout ( Plectropomus maculatus) following severe coral reef habitat degradation after a river flood plume affected the Keppel Islands, Australia. Hard coral cover declined by ~28 % in the 2 yr following the 2010-2011 floods, as did the abundance of young coral trout. Gut contents analysis revealed that diets had shifted from largely crustacean-based to non-preferred prey fishes following the disturbances. These results suggest that newly settled and juvenile coral trout modify their diet and foraging strategy in response to coral habitat degradation. This bottom-up effect of habitat degradation on the diet of a top coral reef predator may incur a metabolic cost, with subsequent effects on growth and survival.

Assessment of aquifer properties, evapotranspiration, and the effects of ditching in the Stoney Brook watershed, Fond du Lac Reservation, Minnesota, 2006-9

Science.gov (United States)

Jones, Perry M.; Tomasek, Abigail A.

2015-01-01

The U.S. Geological Survey, in cooperation with the Fond du Lac Band of Lake Superior Chippewa, assessed hydraulic properties of geologic material, recharge, and evapotranspiration, and the effects of ditching on the groundwater resources in the Stoney Brook watershed in the Fond du Lac Reservation. Geologic, groundwater, and surface-water data were collected during 2006–9 to estimate hydrologic properties in the watershed. Streamflow and groundwater levels in the shallow glacial deposits in the Stoney Brook watershed were analyzed to estimate groundwater-flow directions, groundwater recharge, and evapotranspiration within the watershed and to assess the effect of ditches on surrounding groundwater resources. Groundwater, streamflow, and precipitation data collected during the study (2006–9) can be used to update the U.S. Department of Agriculture’s Natural Resource Conservation Service and Fond du Lac Resource Management Division surface-water models, which are used to evaluate the effect of proposed adjustments to the ditching system on streamflow on wild rice production and aquatic habitats.

The NuSTAR view on Hard-TeV BL Lacs

Science.gov (United States)

Costamante, L.; Bonnoli, G.; Tavecchio, F.; Ghisellini, G.; Tagliaferri, G.; Khangulyan, D.

2018-05-01

Hard-TeV BL Lacs are a new type of blazars characterized by a hard intrinsic TeV spectrum, locating the peak of their gamma-ray emission in the spectral energy distribution (SED) above 2-10 TeV. Such high energies are problematic for the Compton emission, using a standard one-zone leptonic model. We study six examples of this new type of BL Lacs in the hard X-ray band with NuSTAR. Together with simultaneous observations with the Neil Gehrels Swift Observatory, we fully constrain the peak of the synchrotron emission in their SED, and test the leptonic synchrotron self-Compton (SSC) model. We confirm the extreme nature of 5 objects also in the synchrotron emission. We do not find evidence of additional emission components in the hard X-ray band. We find that a one-zone SSC model can in principle reproduce the extreme properties of both peaks in the SED, from X-ray up to TeV energies, but at the cost of i) extreme electron energies with very low radiative efficiency, ii) conditions heavily out of equipartition (by 3 to 5 orders of magnitude), and iii) not accounting for the simultaneous UV data, which then should belong to a different emission component, possibly the same as the far-IR (WISE) data. We find evidence of this separation of the UV and X-ray emission in at least two objects. In any case, the TeV electrons must not "see" the UV or lower-energy photons, even if coming from different zones/populations, or the increased radiative cooling would steepen the VHE spectrum.

Lipid Status of the Two High Latitude Fish Species, Leptoclinus maculatus and Lumpenus fabricii

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Nina N. Nemova

2013-03-01

Full Text Available A comparative study of the lipid status (i.e., the total lipid and phospholipid concentrations and the percentage of fatty acids of the total lipids of adult specimens of daubed shanny (Leptoclinus maculatus from Svalbard waters (Isfjord and slender eel blenny (Lumpenus fabricii from the White Sea (Onega Bay and Tersky shore was performed to study the metabolism and functions of lipids of these fishes in ontogeny and under various ecological conditions. Slender eel blenny from both areas of the White Sea were distinguished by a high level of sphingomyelin compared with the daubed shanny from Svalbard, and the amount of total phospholipids was higher in slender eel blenny from Onega Bay than in slender eel blenny from the Tersky shore. The extent of saturation and the signature of polyenic fatty acids varied according to the specific species of the Stichaeidae family under study. These results demonstrate the differences in the trophoecological and hydrobiological conditions of habitations of these species and highlighted the importance of considering certain trends in the lipid profiles of these fishes as specific features of the organization of the ecological and biochemical mechanisms of adaptation.

Quasi-simultaneous observations of BL Lac object Mrk 501 in X-ray, UV, visible, IR, and radio frequencies

International Nuclear Information System (INIS)

Kondo, Y.; Worrall, D.M.; Mushotzky, R.F.; Hackney, R.L.; Hackney, K.R.H.; Oke, J.B.; Yee, H.K.C.; Neugebauer, G.; Matthews, K.; Feldman, P.A.; Brown, R.L.

1981-01-01

Quasi-simultaneous observations of the BL Lac object Mrk 501 were performed for the first time at X-ray, ultraviolet, visible infrared, and radio frequencies. As the BL Lac objects are known to vary in their flux, such a ''quasi-instantaneous'' spectral energy profile is necessary in order to describe properly the energy generation mechanism. The observed spectral slope from the X-ray to UV regions is positive and continuous, but that from the mid-UV to visible light region becomes gradually flat and possibly turns down toward lower frequencies; the optical-radio emission cannot be accounted for by a single power law. Several theoretical models have been considered for the emission mechanism. In some cases quantitative comparison with the data is not practical. However, most of the models are, at least, not inconsistent with the observations. A quantitative comparison has been peformed with the synchroton self-Compton model; the total spectrum is found consistent with this model. The spectrum from visible light to X-ray is consistent with synchrotron radiation or with inverse-Compton scattering by a hot thermal cloud of electrons. The continuity of the spectral slope from X-ray to UV implied by the current data suggests that the previous estimates of the total luminosity of this BL Lac object has been underestimated by a factor of about 3 or 4

Effect of artificial photoperiod on the blood cell indices of the catfish, Clarias batrachus

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S Srivastava

2010-04-01

Full Text Available The present study is aimed to assess the influence of artificial photoperiod on the blood cell indices of an Indian catfish, Clarias batrachus(Linn.. Blood samples taken from adult fishes exposed to artificial photoperiod of 24L:0D and 0L:24D for a short period of 24 hrs, were analyzed for total RBC, total WBC, differential leukocyte count (DLC and some physiological variables – glucose and chloride. The total RBC and WBC counts were unaffected by both the artificial photoperiod regimes. However, lymphopenia (p<.05 and neutrophilia (p<.05 were observed under 24L:0D photoperiod. Blood chloride levels were significantly higher (p<.05 in 24L:0D whereas blood glucose levels remained unchanged in both the photoperiod treatments. The 0L:24D photoperiod did not produce any significant change in the blood cell indices neither in the physiological variables. The findings indicate that exposure to continuous light for as short a duration as of 24 hrs elicits stress responses in the leukocyte profile of this nocturnal fish and highlights the role of leukocyte profile as potential stress biomarkers in vertebrates.

Données préliminaires sur la diversité du zooplancton du lac Nokoué

African Journals Online (AJOL)

SARAH

31 juil. 2017 ... contribuera davantage à la compréhension de la dynamique de cette communauté biologique du lac. Mots clés ... dans une perspective de gestion durable de la .... ramenés au Laboratoire de Contrôle de Qualité des Eaux.

Dietary beta-1,3 glucan potentiates innate immunity and disease resistance of Asian catfish, Clarias batrachus (L.).

Science.gov (United States)

Kumari, J; Sahoo, P K

2006-02-01

This study investigated the effects of short and prolonged administration of a yeast beta-glucan on non-specific immune parameters, growth rate and the disease resistance of Asian catfish, Clarias batrachus. Fish fed with a basal diet (control) and test diet (basal diet supplemented with 0.1% glucan) for 1, 2 and 3 weeks were assayed for superoxide production, serum myeloperoxidase (MPO) content, natural haemagglutinin level, complement and lysozyme activities. Fish were weighed at weekly intervals and specific growth rate (SGR, % increase in body weight per day) was determined. After each week, fish were challenged with Aeromonas hydrophila to measure the level of protection. Results showed that glucan administration at 0.1% in feed, significantly (Pcomplement activity and SGR were not affected by the dietary supplementation of yeast glucan. As glucan feeding at 0.1% for 1 week is able to enhance the non-specific immunity and disease resistance of catfish efficiently, short-term feeding might be used in farmed catfish diets to enhance disease resistance.

Changes in brain monoamine levels and monoamine oxidase activity in the catfish, Clarias batrachus, during chronic treatments with mercurials

International Nuclear Information System (INIS)

Kirubagaran, R.; Joy, K.P.

1990-01-01

In mammals, the central nervous system is the primary target for CH 3 Hg poisoning which is clinically known as Minamata disease. Hg is a widely recognized neurotoxin and has been reported to impair brain monoamine neurotransmitter metabolism. Reports on effects of Hg on brain monoamine activity in fishes are scarce. In the present study, therefore, changes in the brain monoamine levels and the degradation enzyme, monoamine oxidase (MAO), are described in the catfish, Clarias batrachus, exposed to sublethal concentrations of mercuric chloride (HgCl 2 -inorganic Hg), methylmercuric chloride (CH 3 HgCl-organic Hg), and a commercial mercurial fungicide formulation, emisan 6 (methoxyethyl Hg-organic Hg) for 45, 90 and 180 d during gonadal recrudescence. These intervals correspond to late preparatory, prespawning and spawning phases, respectively, of the annual reproductive cycle of the catfish

Effet des conditions climatiques sur le niveau du lac Sidi Ali (Moyen Atlas, Maroc

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Claude Martin

2011-11-01

Full Text Available Le lac Sidi Ali est un lac naturel d'altitude (2070-2080 m, sans exutoire superficiel, déterminé par le barrage d'une coulée basaltique. Doté d'un bassin versant apparent de 15,6 km2, il est alimenté par des eaux de ruissellement et par des sources karstiques. Son niveau subit des variations très fortes, annuelles et interannuelles, sous le contrôle des conditions climatiques, et en particulier des pluies et de l'évapotranspiration. Les périodes de sécheresse qui ont marqué les trois dernières décennies, se sont traduites par un abaissement du niveau de près de 7 m. Mais les précipitations abondantes des années 2008-09 et 2009-10 ont provoqué une nette remontée. Une régression multiple d'assez bonne qualité (r = 0,87 lie la variation annuelle du niveau (d'août à août à différents paramètres (conditions climatiques et niveau initial du lac.Lake Sidi Ali is a natural lake at high altitude (2070-2080 m, without surface outlet, determined by the dam of a basalt flow. With an apparent catchment of 15.6 km2, it is fed by runoff and karst springs. Its level shows strong annual and interannual variations, depending on weather conditions, particularly rainfall and evapotranspiration. Droughts that have marked the last three decades have resulted in a lowering of about 7 m of the water level. But heavy rainfall that occurred in 2008-09 and 2009-10 caused a marked rise. A multiple regression of sufficient quality (r = 0.87 binds the annual change (from august to august at differents parameters (weather conditions and initial level of the lake.

Starch-Glycerol Based Edible Film and Effect of Rosella (Hibiscus Sabdariffa Linn Extract and Surimi Dumbo Catfish (Clarias gariepinus Addition on Its Mechanical Properties

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Endaruji Sedyadi

2016-10-01

Full Text Available Effect of Rosella (Hibiscus Sabdariffa Linn Extract and Surimi Dumbo catfish (Clarias gariepinus addition on Starch-Based Edible Film-Glycerol Mechanical Properties has been done. The purpose of this study is to create an active environment-friendly packaging material. Surimi additions are intended to improve the mechanical properties of bioplastics and additions of Rosella extract intended as a bio-indicator of acidity. The method used was Solvent Casting. An amount of surimi and rosella extract varied to obtain the best mechanical properties. The results shows that the addition of surimi and rosella flower extract significantly effect the elongation of Edible films produced up to 27%.

Formulasi bubur bayi MPASI yang diperkaya hidrolisat protein ikan lele dumbo (Clarias gariepinus

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Veriani Aprilia

2016-08-01

Full Text Available ABSTRACTBackground: Malnutrition become the problem in Indonesia. Complementary feeding has the role in solving it. Most of commercial complementary feeding are enriched by vegetable protein, whereas animal protein has more complete amino acid and better digestibility. Unfortunately, consuming animal proteinoften raises concern because of its allergenicity. Catfish (Clarias gariepinus can be used as a source of high animal protein in the diet that may solve the nutritional problem after reduction of its allergen.Objectives: To develope formulate of complementary feeding porridge enriched with hydrolized protein from catfish muscle.Methods: This was experimental study. HPIL and HPIK was enzymatic hydrolized products of catfish using crude and commercial papain, respectively. Overall and partial hedonic test used 23 mothers as panelists, then selected formula were tested its acceptance by 9 babies using face scale. Nutrient content of porridge were analyzed for protein, carbohydrate, fat, protein, and water.Results: Hydrolysis of catfish using papain made the changes in color, taste, and aroma. The bitter taste limited the uses, maximum amount was 25%. Porridge with the addition of HPIK were chosen by mothers and babies panelists, whereas HPIL did not. Protein content of formulated product were lower than commercial product, but carbohydrate and fat content were higher.Conclusions: Porridge formula with addition of 25% HPIK my be developed as alternative product of complementary feeding.KEYWORDS: protein, papain, catfish, protein hydrolisate, complementary feedingABSTRAKLatar belakang: Kekurangan gizi masih menjadi masalah di Indonesia. MPASI memiliki peran penting dalam mengatasi masalah tersebut. MPASI pada umumnya diperkaya oleh protein nabati, padahal protein hewani mengandung asam amino dan daya cerna yang lebih baik. Namun demikian, protein hewanimeningkatkan risiko alergi pada bayi. Lele (Clarias gariepinus dapat dijadikan

UV spectrum of the BL Lac object PKS 0521-36

Energy Technology Data Exchange (ETDEWEB)

Danziger, I.J. (European Southern Observatory, Garching (Germany, F.R.)); Bergeron, J. (Centre National de la Recherche Scientifique, 75 - Paris (France). Inst. d' Astrophysique); Fosbury, R.A.E. (Royal Greenwich Observatory, Hailsham (UK)); Maraschi, L.; Treves, A. (Consiglio Nazionale delle Ricerche, Milan (Italy). Lab. di Fisica Cosmica; Milan Univ. (Italy). Ist. di Fisica); Tanzi, E.G. (Consiglio Nazionale delle Ricerche, Milan (Italy). Lab. di Fisica Cosmica)

1983-05-01

Ultraviolet observations (1200 to 3000 A) with the IUE satellite of the BL Lac object PKS 0521-36 are presented. The only emission line which appears clearly in the spectrum is Ly..cap alpha.., which is asymmetric with a component displaced approx. 3000 km s/sup -1/ to the red. The intensity of the line and the upper limits on other lines are compared with the model calculations on QSOs and Seyfert nuclei by Kwan and Krolik. The continuous energy distribution is discussed, combining non-simultaneous observations from the ultraviolet to the infrared. The spectral range of the non-thermal source from far IR to far UV can be described by a single power law of index -1.5.

Northern hemisphere mid-latitude geomagnetic anomaly revealed from Levantine Archaeomagnetic Compilation (LAC).

Science.gov (United States)

Shaar, R.; Tauxe, L.; Agnon, A.; Ben-Yosef, E.; Hassul, E.

2015-12-01

The rich archaeological heritage of Israel and nearby Levantine countries provides a unique opportunity for archaeomagnetic investigation in high resolution. Here we present a summary of our ongoing effort to reconstruct geomagnetic variations of the past several millennia in the Levant at decadal to millennial resolution. This effort at the Southern Levant, namely the "Levantine Archaeomagnetic Compilation" (LAC), presently consists of data from over 650 well-dated archaeological objects including pottery, slag, ovens, and furnaces. In this talk we review the methodological challenges in achieving a robust master secular variation curve with realistic error estimations from a large number of different datasets. We present the current status of the compilation, including the southern and western Levant LAC data (Israel, Cyprus, and Jordan) and other published north-eastern Levant data (Syria and southern Turkey), and outline the main findings emerging from these data. The main feature apparent from the new compilation is an extraordinary intensity high that developed over the Levant region during the first two millennia BCE. The climax of this event is a double peak intensity maximum starting at ca. 1000 BCE and ending at ca. 735 BCE, accompanied with at least two events of geomagnetic spikes. Paleomagnetic directions from this period demonstrate anomalies of up to 20 degrees far from the averaged GAD field. This leads us to postulate that the maximum in the intensity is a manifestation of an intense mid-latitude local positive geomagnetic anomaly that persisted for over two centuries.

Toxicity of buprofezin on the survival of embryo and larvae of African catfish, Clarias gariepinus (Bloch.

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Kasi Marimuthu

Full Text Available Buprofezin is an insect growth regulator and widely used insecticide in Malaysia. The present study evaluated the toxic effects of buprofezin on the embryo and larvae of African catfish (Clarias gariepinus as a model organism. The embryos and larvae were exposed to 7 different concentrations (0, 0.05, 0.5, 5, 25, 50 and 100 mg/L of buprofezin. Each concentration was assessed in five replicates. Eggs were artificially fertilized and 200 eggs and larvae were subjected to a static bath treatment for all the concentrations. The mortality of embryos was significantly increased with increasing buprofezin concentrations from 5 to 100 mg/L (p0.05 in the LC50 values obtained at 24 and 48 h exposure times. Malformations were observed when the embryos and larvae exposed to more than 5 mg/L. The results emerged from the study suggest that even the low concentration (5 mg/L of buprofezin in the aquatic environment may have adverse effect on the early embryonic and larval development of African catfish.

Study feature of variability extragalactic radio sources 3C 446 and BL Lac in the centimeter wavelength range

International Nuclear Information System (INIS)

Sukharev, A.L.

2015-01-01

This work presents the results of the analysis of long-term monitoring (over 40 years) changes in radio fluxes of the two extragalactic sources - 3C 446, and BL Lac. Observations at frequencies of 14.5, 8, 4.8 GHz were obtained in the Michigan Radio Astronomy Observatory (UMRAO). With using Fourier filtering were selected 0- C (short-period), and the trend component of flux variations that were analyzed separately with using the wavelet-analysis method. Each of these components is associated with certain physical processes in the 'core-accretion disk-jet' system. Were constructed time-frequency wavelet-spectra showing the changes of the frequency composition of the investigated data over time. For the trend component values of the main periods of -4-9 years (3C 446) and -8 years (BL Lac), for 0- C component -0.8-3 years (3C 446) and -0.6-4 years (BL Lac) and they appear in the temporal and structural changes of the jet. On the basis of calculating the global wavelet-spectra in the frequency range identified main phases activity of radio sources. Obtained comparison between the dynamics of jets (Mojave VLBI images), and change the frequency spectral structure of the studied data. With bandpass wavelet filtering, flux components corresponding to the main periods in the spectra, were identified and also found the delay between the observation frequencies in spectral bands of these periods

Fish communities in man-made lakes = Peuplements ichtyologiques des lacs de barrage

OpenAIRE

Jackson, P.N.B.; Marshall, B.E.; Paugy, Didier

1988-01-01

Il existe actuellement des réservoirs artificiels sur de nombreuses rivières africaines. Leur construction a modifié les conditions écologiques (facteurs édaphiques, apports en éléments nutritifs) et changé la composition des peuplements ichtyologiques ... Le barrage lui-même peut être un obstacle pour des poissons tels que les anguilles ou les mulets migrants depuis la mer et entraîner la disparition des espèces en amont ... Les lacs de barrage ont une vaste zone pélagique favorable au déve...

Évaluation du niveau de pollution par les métaux lourds des lacs ...

African Journals Online (AJOL)

La présente étude a pour objectif principal d'évaluer le niveau de pollution métallique des lacs Bini et Dang (Ngaoundéré, Cameroun) à travers l'analyse des eaux et des sédiments de surface. La concentration des métaux lourds (Ni, Cr, Fe, Pb, Cd, Zn) a été mesurée par spectrophotométrie d'absorption atomique.

6-Desaturase-Like Encoding Gene Introduction in Catfish (Clarias gariepinus

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Anny Hary Ayu

2017-11-01

Full Text Available African catfish (Clarias gariepinus is one of the economically valuable aquaculture fish species in Indonesia. This research was aimed to produce F0 transgenic catfish carrying masou salmon Δ6-desaturase-like (OmΔ6FAD gene. The Δ6-desaturase enzyme is involved in highly unsaturated fatty acid biosynthesis. Transgenic catfish was produced by sperm-mediated gene transfer using electroporation method. In this study, as the first step, sperms were electroporated with three different OmΔ6FAD concentration (25, 50, and 100 µg mL-1 to have the highest sperm viability after electroporation (125 V/cm, pulse frequency 5 times, pulse length 30 millisecond, pulse interval 0.1 second. The highest sperm viability and sperm carrying OmΔ6FAD were obtain at 100 µg mL-1. This concentration was then used to produce F0 transgenic catfish in the second step. Sperm motility, sperm viability, fertilization rate, hatching rate, and larval survival at 14 days after hatching were the same as the controls (p>0.05. Genomic DNA was extracted from caudal fin and then used as template to identify transgenic F0 by PCR method using specific primer for OmΔ6FAD gene. The PCR result showed that 53.84% of F0 carried OmΔ6FAD gene. The result of fatty acid analysis showed that EPA and DHA contents of F0 transgenic fish and non-transgenic fish were similar.   Keywords: catfish, Δ6-desaturase-like gene, fatty acids, electroporation

In vitro transcription accurately predicts lac repressor phenotype in vivo in Escherichia coli

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Matthew Almond Sochor

2014-07-01

Full Text Available A multitude of studies have looked at the in vivo and in vitro behavior of the lac repressor binding to DNA and effector molecules in order to study transcriptional repression, however these studies are not always reconcilable. Here we use in vitro transcription to directly mimic the in vivo system in order to build a self consistent set of experiments to directly compare in vivo and in vitro genetic repression. A thermodynamic model of the lac repressor binding to operator DNA and effector is used to link DNA occupancy to either normalized in vitro mRNA product or normalized in vivo fluorescence of a regulated gene, YFP. An accurate measurement of repressor, DNA and effector concentrations were made both in vivo and in vitro allowing for direct modeling of the entire thermodynamic equilibrium. In vivo repression profiles are accurately predicted from the given in vitro parameters when molecular crowding is considered. Interestingly, our measured repressor–operator DNA affinity differs significantly from previous in vitro measurements. The literature values are unable to replicate in vivo binding data. We therefore conclude that the repressor-DNA affinity is much weaker than previously thought. This finding would suggest that in vitro techniques that are specifically designed to mimic the in vivo process may be necessary to replicate the native system.

Salinity-dependent mechanisms of copper toxicity in the galaxiid fish, Galaxias maculatus.

Science.gov (United States)

Glover, Chris N; Urbina, Mauricio A; Harley, Rachel A; Lee, Jacqueline A

2016-05-01

The euryhaline galaxiid fish, inanga (Galaxias maculatus) is widely spread throughout the Southern hemisphere occupying near-coastal streams that may be elevated in trace elements such as copper (Cu). Despite this, nothing is known regarding their sensitivity to Cu contamination. The mechanisms of Cu toxicity in inanga, and the ameliorating role of salinity, were investigated by acclimating fish to freshwater (FW), 50% seawater (SW), or 100% SW and exposing them to a graded series of Cu concentrations (0-200μgL(-1)) for 48h. Mortality, whole body Cu accumulation, measures of ionoregulatory disturbance (whole body ions, sodium (Na) influx, sodium/potassium ATPase activity) and ammonia excretion were monitored. Toxicity of Cu was greatest in FW, with mortality likely resulting from impaired Na influx. In both FW and 100% SW, ammonia excretion was significantly elevated, an effect opposite to that observed in previous studies, suggesting fundamental differences in the effect of Cu in this species relative to other studied fish. Salinity was protective against Cu toxicity, and physiology seemed to play a more important role than water chemistry in this protection. Inanga are sensitive to waterborne Cu through a conserved impairment of Na ion homeostasis, but some effects of Cu exposure in this species are distinct. Based on effect concentrations, current regulatory tools and limits are likely protective of this species in New Zealand waters. Copyright © 2016 Elsevier B.V. All rights reserved.

Species delineation and hybrid identification using diagnostic nuclear markers for Plectropomus leopardus and Plectropomus maculatus

KAUST Repository

He, Song

2018-06-01

Diagnostic molecular markers are an essential tool in the study of species’ ecology and evolution, particularly in closely related and sympatric species. Furthermore, the increasing awareness of wild-hybrids has led to a renewed interest in rapid diagnostic assays. Here, we test the ability of two mitochondrial (Cytb and COI) and two nuclear markers (ETS2 and TMO-4c4) to confidently discriminate purebred P. leopardus and P. maculatus and their first-generation hybrids. A sample of 48 purebred individuals and 91 interspecific hybrids were used in this study and their delineation confirmed using a set of microsatellite markers. Our results indicate mitochondrial markers could not distinguish even between species but both nuclear markers confidently identified species and first-generation hybrids. However, later-generation hybrids could not always be confidently identified due to on-going introgression between species. Our findings provide a robust tool to distinguish purebred individuals and interspecific hybrids in a pair of species with an unexpectedly high incidence of hybridization. The quick species discrimination abilities provided by these diagnostic markers are important for stock assessment and recruitment studies of these important fishery species.

Effects of dietary antioxidant of tomato extract and lycopene on Carassius auratus and Xiphophorus maculatus

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Cynthia Montoya M.

2014-06-01

Full Text Available Objective. Evaluate the effect on tegument pigmentation, survival, growth and antioxidant capacity in diets supplemented with tomato extract and lycopene as additives in experimental feed for Carassius auratus and Xiphophorus maculatus. Materials and methods. The additives were added in different concentrations to a basic diet. We performed beginning and an ending biometrics for 100% of the population in each bioassay. The growth and survival of organisms were evaluated. The antioxidant capacity was analyzed by ABTS assay, both in the tomato extract sample as well as in foods used in different bioassays. The concentration of lycopene was determined in food and liver and muscle samples of fish fed with it. Acquired pigmentation of fish was assessed through photographs analyzed with Adobe Photoshop®. The results were evaluated by analysis of variance, and when differences were found (p0.05 on pigmentation and growth of the organisms under the established experimental conditions was obtained. Significant differences in antioxidant capacity (p<0.05 were obtained in foods with added lycopene. Conclusions. The inclusion of lycopene or tomato extract in food for the organisms used is not recommended to improve pigmentation, but further studies are needed to demonstrate antioxidant effect.

Species delineation and hybrid identification using diagnostic nuclear markers for Plectropomus leopardus and Plectropomus maculatus

KAUST Repository

He, Song; Harrison, Hugo B.; Berumen, Michael L.

2018-01-01

Diagnostic molecular markers are an essential tool in the study of species’ ecology and evolution, particularly in closely related and sympatric species. Furthermore, the increasing awareness of wild-hybrids has led to a renewed interest in rapid diagnostic assays. Here, we test the ability of two mitochondrial (Cytb and COI) and two nuclear markers (ETS2 and TMO-4c4) to confidently discriminate purebred P. leopardus and P. maculatus and their first-generation hybrids. A sample of 48 purebred individuals and 91 interspecific hybrids were used in this study and their delineation confirmed using a set of microsatellite markers. Our results indicate mitochondrial markers could not distinguish even between species but both nuclear markers confidently identified species and first-generation hybrids. However, later-generation hybrids could not always be confidently identified due to on-going introgression between species. Our findings provide a robust tool to distinguish purebred individuals and interspecific hybrids in a pair of species with an unexpectedly high incidence of hybridization. The quick species discrimination abilities provided by these diagnostic markers are important for stock assessment and recruitment studies of these important fishery species.

Residues in the H+ Translocation Site Define the pKa for Sugar Binding to LacY†

Science.gov (United States)

Smirnova, Irina; Kasho, Vladimir; Sugihara, Junichi; Choe, Jun-Yong; Kaback, H. Ronald

2009-01-01

A remarkably high pKa of approximately 10.5 has been determined for sugar-binding affinity to the lactose permease of Escherichia coli (LacY), indicating that, under physiological conditions, substrate binds to fully protonated LacY. We have now systematically tested site-directed replacements for the residues involved in sugar binding, as well as H+ translocation and coupling, in order to determine which residues may be responsible for this alkaline pKa. Mutations in the sugar-binding site (Glu126, Trp151, Glu269) markedly decrease affinity for sugar but do not alter the pKa for binding. In contrast, replacements for residues involved in H+ translocation (Arg302, Tyr236, His322, Asp240, Glu325, Lys319) exhibit pKa values for sugar binding that are either shifted toward neutral pH or independent of pH. Values for the apparent dissociation constant for sugar binding (Kdapp) increase greatly for all mutants except neutral replacements for Glu325 or Lys319, which are characterized by remarkably high affinity sugar binding (i.e., low Kdapp) from pH 5.5 to pH 11. The pH dependence of the on- and off-rate constants for sugar binding measured directly by stopped-flow fluorometry implicates koff as a major factor for the affinity change at alkaline pH and confirms the effects of pH on Kdapp inferred from steady-state fluorometry. These results indicate that the high pKa for sugar binding by wild-type LacY cannot be ascribed to any single amino acid residue but appears to reside within a complex of residues involved in H+ translocation. There is structural evidence for water bound in this complex, and the water could be the site of protonation responsible for the pH dependence of sugar binding. PMID:19689129

77 FR 27245 - Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN

Science.gov (United States)

2012-05-09

... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R3-R-2012-N069; FXRS1265030000S3-123-FF03R06000] Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN AGENCY: Fish and... plan (CCP) and environmental assessment (EA) for Big Stone National Wildlife Refuge (Refuge, NWR) for...

An Analysis of Periodic Components in BL Lac Object S5 0716 +714 with MUSIC Method

Science.gov (United States)

Tang, J.

2012-01-01

Multiple signal classification (MUSIC) algorithms are introduced to the estimation of the period of variation of BL Lac objects.The principle of MUSIC spectral analysis method and theoretical analysis of the resolution of frequency spectrum using analog signals are included. From a lot of literatures, we have collected a lot of effective observation data of BL Lac object S5 0716 + 714 in V, R, I bands from 1994 to 2008. The light variation periods of S5 0716 +714 are obtained by means of the MUSIC spectral analysis method and periodogram spectral analysis method. There exist two major periods: (3.33±0.08) years and (1.24±0.01) years for all bands. The estimation of the period of variation of the algorithm based on the MUSIC spectral analysis method is compared with that of the algorithm based on the periodogram spectral analysis method. It is a super-resolution algorithm with small data length, and could be used to detect the period of variation of weak signals.

MORPHOLOGICAL CHARACTERIZATION OF THE AFRICAN CATFISH (Clarias gariepinus BURCHELL, 1822 STRAINS INTRODUCED TO INDONESIA

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Bambang Iswanto

2015-12-01

Full Text Available African catfish (Clarias gariepinus Burchell, 1822 has become a great important species in Indonesian aquaculture. Several strains of the African catfish have been introduced to Indonesia for aquaculture purposes, initiated by Dumbo strain from Taiwan in 1985, followed by Paiton strain from Thailand in 1998, then Egypt strain from Egypt in 2007, Masamo strain from Thailand in 2010 and later Kenya strain from Kenya in 2011. Since its introductions, there were no reports yet on their characterization studies. The present study was conducted to morphologically characterize the strains of African catfish introduced to Indonesia, i.e. Dumbo, Paiton, Egypt, Masamo, and Kenya strains. Morphometric and meristic data obtained were analyzed using Principal Component Analysis. Results of the morphometric characterization in the present study revealed that Dumbo, Paiton, Masamo, and Kenya strains were indistinguishable, while morphometric characteristic of Egypt strain was more or less different from those of the other strains. On the other hand, results of the meristic characterization suggested that meristic characteristics of all strains of the introduced African catfish were not different from each other. Therefore, to keep the genetic purity of those introduced strains, they should be properly maintained in isolated places.

Bistable behavior of the lac operon in E. coli when induced with a mixture of lactose and TMG

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Orlando Díaz-Hernández

2010-07-01

Full Text Available In this work we investigate multistability in the lac operon of Escherichia coli when it is induced by a mixture of lactose and the non-metabolizable thiomethyl galactoside (TMG. In accordance with previously published experimental results and computer simulations, our simulations predict that: (1 when the system is induced by TMG, the system shows a discernible bistable behavior while, (2 when the system is induced by lactose, bistability does not disappear but excessively high concentrations of lactose would be required to observe it. Finally, our simulation results predict that when a mixture of lactose and TMG is used, the bistability region in the extracellular glucose concentration vs. extracellular lactose concentration parameter space changes in such a way that the model predictions regarding bistability could be tested experimentally. These experiments could help to solve a recent controversy regarding the existence of bistability in the lac operon under natural conditions.

Bistable behavior of the lac operon in E. coli when induced with a mixture of lactose and TMG.

Science.gov (United States)

Díaz-Hernández, Orlando; Santillán, Moisés

2010-01-01

In this work we investigate multistability in the lac operon of Escherichia coli when it is induced by a mixture of lactose and the non-metabolizable thiomethyl galactoside (TMG). In accordance with previously published experimental results and computer simulations, our simulations predict that: (1) when the system is induced by TMG, the system shows a discernible bistable behavior while, (2) when the system is induced by lactose, bistability does not disappear but excessively high concentrations of lactose would be required to observe it. Finally, our simulation results predict that when a mixture of lactose and TMG is used, the bistability region in the extracellular glucose concentration vs. extracellular lactose concentration parameter space changes in such a way that the model predictions regarding bistability could be tested experimentally. These experiments could help to solve a recent controversy regarding the existence of bistability in the lac operon under natural conditions.

Characterisation and discrimination of various types of lac resin using gas chromatography mass spectrometry techniques with quaternary ammonium reagents.

Science.gov (United States)

Sutherland, K; del Río, J C

2014-04-18

A variety of lac resin samples obtained from artists' suppliers, industrial manufacturers, and museum collections were analysed using gas chromatography mass spectrometry (GCMS) and reactive pyrolysis GCMS with quaternary ammonium reagents. These techniques allowed a detailed chemical characterisation of microgram-sized samples, based on the detection and identification of derivatives of the hydroxy aliphatic and cyclic (sesquiterpene) acids that compose the resin. Differences in composition could be related to the nature of the resin, e.g. wax-containing (unrefined), bleached, or aged samples. Furthermore, differences in the relative abundances of aliphatic hydroxyacids appear to be associated with the biological source of the resin. The diagnostic value of newly characterised lac components, including 8-hydroxyacids, is discussed here for the first time. Identification of derivatised components was aided by AMDIS deconvolution software, and discrimination of samples was enhanced by statistical evaluation of data using principal component analysis. The robustness of the analyses, together with the minimal sample size required, make these very powerful approaches for the characterisation of lac resin in museum objects. The value of such analyses for enhancing the understanding of museum collections is illustrated by two case studies of objects in the collection of the Philadelphia Museum of Art: a restorer's varnish on a painting by Luca Signorelli, and a pictorial inlay in an early nineteenth-century High Chest by George Dyer. Copyright © 2014 Elsevier B.V. All rights reserved.

Kinerja probiotik Bacillus sp. pada pendederan benih ikan lele Clarias sp. yang diinfeksi Aeromonas hydrophila

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, Sukenda

2016-12-01

Full Text Available ABSTRACT This experiment was conducted to assess performance of Bacillus sp. probiotic on catfish juvenile Clarias sp. infected by Aeromonas hydrophila. The probiotic content in the diets were 0% (K+ and K-, 1%, and 2% in duplicates. This experiment used randomized design with four treatments and two replications. Juveniles with average body weight of 3.22±0.15 g/fish were reared in the 1.5×2.8×0.5 m3 pond with density of 800 fish/pond. Fish were reared for 30 days and fed three times a day at rate 8% of  total body weight. At day 31, catfish were challenged by A. hydrophila 0.1 mL (106 cfu/mL. Post infection observation was carried out ten days with density 10 fish/aquaria. The result showed that fish fed diet containing 2% probiotic gave the best probiotic performance with survival rate of catfish 83.33% after challenged, spesific growth rate 5.40%, and 0,75 of feed conversion ratio. The results of the blood profile showed significantly better results in the treatment of probiotics compared to the positive control after challenge test A. hydrophila. Probiotic Bacillus sp. has given as much as 2% on feed provides better performance on catfish juvenile. Keywords: probiotic, Bacillus sp., A. hydrophila, catfish juvenille, growth  ABSTRAK Penelitian ini bertujuan untuk menguji kinerja probiotik Bacillus sp. dalam pakan pada pendederan benih ikan lele Clarias sp. yang diinfeksi bakteri Aeromonas hydrophila. Penelitian ini menggunakan rancangan acak lengkap dengan empat perlakuan yaitu kandungan probiotik dalam pakan perlakuan yaitu 0% (K+ dan K-, 1%,  dan 2%, masing-masing dengan dua ulangan. Ikan lele yang digunakan memiliki bobot rata-rata 3,22±0,15 g/ekor, dipelihara dalam kolam terpal berukuran 1,5×2,8×0,5 m3 dengan kepadatan 800 ekor/kolam. Ikan dipelihara selama 30 hari dengan frekuensi pemberian pakan tiga kali sehari sebanyak 8% dari bobot tubuh ikan. Hari ke-31 benih lele diinjeksi bakteri A. hydrophila dosis 0,1 m

Lac du Flambeau Band of Lake Superior Chippewa Indians Strategic Energy Plan

Energy Technology Data Exchange (ETDEWEB)

Bryan Hoover

2009-11-16

This plan discusses the current energy use on the Lac du Flambeau Reservation, the current status of the Tribe's energy program, as well as the issues and concerns with energy on the reservation. This plan also identifies and outlines energy opportunities, goals, and objectives for the Tribe to accomplish. The overall goal of this plan is to address the energy situation of the reservation in a holistic manner for the maximum benefit to the Tribe. This plan is an evolving document that will be re-evaluated as the Tribe's energy situation changes.

Estudo de carcaça do bagre africano (Clarias gariepinus em diferentes categorias de peso Study of African Catfish (Clarias gariepinus carcass in different weight categories

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Adriana Aparecida Pinto

1999-11-01

Full Text Available O objetivo deste experimento foi estudar carcaças de Clarias gariepinus, em três categorias de peso (P1=inferior a 1kg; P2=de 1 a 2kg e P3=superior a 2kg, para analisar o rendimento de carcaça com cabeça (RCC, sem cabeça (RCS, filé (RFI, músculos abdominais (RMA, partes comestíveis (RPC, tronco limpo (RTL, porcentagem de pele (PPE, cabeça (PCA, vísceras (PVI, resíduos totais (PRE e determinar a composição proximal do filé (proteína bruta, umidade, gordura e cinza. Foram utilizados 60 bagres, em delineamento inteiramente casualizado, 3 tratamentos com 20 repetições, em nível de significância de 5%. O rendimento de filé foi maior para P2 (38,61% que para P1 e P3. O rendimento das partes comestíveis e tronco limpo foram superiores para P2 (RPC=46,27% e RTL=56,67%, mas sem diferirem do P3. O rendimento de carcaça sem cabeça foi maior para P3, não diferindo de P2. O P2 foi inferior para PPE (4,64%, PCA (23,62% e PRE (53,73%, sem diferir de P3, para porcentagem de cabeça e de resíduos totais. Não houve diferença significativa para rendimentos dos músculos abdominais, carcaça com cabeça e vísceras. P2 (2,25% e 77,49% não diferiu do P1 (1,51% e 77,78% e P3 (3,03% e 76,39%, para gordura e umidade, respectivamente, enquanto, para proteína bruta, não houve diferença significativa. Conclui-se que P2 apresentou melhores rendimentos de filetagem, ao passo que a composição proximal do filé, nas três categorias de peso, foi relativamente similar, com aumento de deposição de gordura nos peixes acima de 1kg de peso vivo.The aim of this experiment was to study Clarias gariepinus carcass in three weight categories (P1=below 1kg; P2= 1 to 2kg and P3=over 2kg to analyze yield of carcass with head (YCH, without head (YCW, fillet (YF, abdominal muscles (YAM, eatable parts (YEP, dressed out (YDO and percentages of skin (PSK, head (PHE, viscera (PVI, total residues (PTR; and to determine the proximate composition of fillet (crude

Search for relation between flares and photometric variability outside of flares in EV Lac

International Nuclear Information System (INIS)

Rojzman, G.Sh.

1984-01-01

The observations of the flare star EV Lac in July-September 1981 have confirmed the existence of photometric variability outside the flares during the night. It was found that, as a rule, a slow increase of brightness in U and B bands during 1-2 hours preceded the flares. It is suggested that the variability outside the flares is the result of the variability of chpomospheric emission lines and continuum that are emitted by the chromospheric preflare formations

REPEUPLEMENTS EN ALEVINS NOURRIS ET DÉMOGRAPHIE DE LA POPULATION DE TRUITE (SALMO TRUTTA L. DANS LE REDON, UN AFFLUENT DU LAC LÉMAN INTERROMPU PAR UN OBSTACLE

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CHAMPIGNEULLE A.

2003-01-01

Full Text Available La démographie d’une population de truite (Salmo trutta L. a été étudiée, dans un contexte de repeuplements en alevins nourris, sur le Redon, un affluent du lac Léman. On trouve sur le Redon une situation typique de nombreux affluents du Léman : une zone aval ouverte sur le lac mais rapidement interrompue par un obstacle empêchant la remontée des truites de lac. Des relâchers d’alevins nourris issus d’œufs de géniteurs sauvages de truite de lac ou de géniteurs domestiques, pratiqués en fin de printemps-début été à des densités de 40-60 ind./100 m2, fournissent un recrutement additionnel important pouvant constituer la part dominante du peuplement automnal en 0 +, puis 1 +. Sur les zones ouvertes à la pêche, colonisées ou non par la truite de lac, la densité de la population automnale en place s’effondre entre le stade 1 + et les stades > 1 +. Les résultats comparatifs entre zones ouvertes ou fermées à la pêche indiquent que la pêche peut être un facteur de mortalité important. La dynamique comparée des truites d’origine lacustre ou sédentaire suggère l’existence d’un taux de sédentarisation plus faible pour les 1 + issus de truites de lac comparativement aux 1 + issus de la fraie de truites sédentaires en zone de réserve. Une expérimentation suggère l’existence de mouvements de dévalaison ayant lieu avant octobre et touchant préférentiellement les 0 + d’origine lacustre ayant eu la croissance initiale la plus forte. L’étude montre que : - des alevins nourris d’origine lacustre ou domestique, relâchés en fin de printemps-début été, fournissent des géniteurs de truite de lac remontant dans la rivière de relâcher, avec cependant une proportion moindre (4 fois dans le cas de l’origine domestique comparativement à l’origine lacustre. Malgré leur forte contribution aux stades de juvéniles 0 + et 1 +, les alevins domestiques de pisciculture contribuent peu aux retours de g

The UV spectrum of the BL Lac object PKS 0521-36

International Nuclear Information System (INIS)

Danziger, I.J.; Bergeron, J.; Maraschi, L.; Treves, A.; Milan Univ.; Tanzi, E.G.

1983-01-01

Ultraviolet observations (1200 to 3000 A) with the IUE satellite of the BL Lac object PKS 0521-36 are presented. The only emission line which appears clearly in the spectrum is Lyα, which is asymmetric with a component displaced approx. 3000 km s - 1 to the red. The intensity of the line and the upper limits on other lines are compared with the model calculations on QSOs and Seyfert nuclei by Kwan and Krolik. The continuous energy distribution is discussed, combining non-simultaneous observations from the ultraviolet to the infrared. The spectral range of the non-thermal source from far IR to far UV can be described by a single power law of index -1.5. (author)

Two-dimensional proteomic analysis of gonads of air-breathing catfish, Clarias batrachus after the exposure of endosulfan and malathion.

Science.gov (United States)

Laldinsangi, C; Vijayaprasadarao, K; Rajakumar, A; Murugananthkumar, R; Prathibha, Y; Sudhakumari, C C; Mamta, S K; Dutta-Gupta, A; Senthilkumaran, B

2014-05-01

Endocrine disrupting chemicals have raised public concern, since their effects have been found to interfere with the physiological systems of various organisms, especially during critical stage of development and reproduction. Endosulfan and malathion, pesticides widely used for agricultural purposes, have been known to disrupt physiological functions in aquatic organisms. The current work analyzes the effects of endosulfan (2.5 parts per billion [ppb]) and malathion (10 ppb) on the reproductive physiology of catfish (Clarias batrachus) by evaluating protein expression profiles after 21 days of exposure. The proteomic profile of testis and ovary after exposure to endosulfan showed downregulation of proteins such as ubiquitin and Esco2, and upregulation in melanocortin-receptor-2 respectively. Malathion exposed ovary showed upregulated prolactin levels. Identification of proteins differentially expressed in gonads due to the exposure to these pesticides may serve as crucial indications to denote their disruptive effects at the level of proteins. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of Cooking Method on the Proximate, Amino Acid and Fatty Acid Compositions of Clarias gariepinus and Oreochromis niloticus

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Omolara Olusola Oluwaniyi

2016-10-01

Full Text Available The proximate, amino acid and fatty acid compositions of the fillet and oil from Clarias gariepinus (Catfish and Oreochromis niloticus (Tilapia were determined. The moisture content ranged from 76.27 % for catfish to 79.97 % for tilapia while the oil content ranged from 7.80 % for tilapia and 11.00 % for catfish. Ash content was in the range 8.03 – 9.16 % and the protein content was 15.83 - 18.48 %. Cooking – boiling, roasting or frying – resulted in a variation in the nutrient composition but with no significant effect on the amino acid composition except for the samples fried with palm oil which resulted in significantly reduced essential amino acids contents. All the fish samples – both fresh and processed – have amino acid scores less than 100, with lysine, threonine and the sulphur-containing amino acids being among the limiting amino acids. Both fish samples contain more unsaturated than saturated fatty acids.

Various mutations compensate for a deleterious lacZα insert in the replication enhancer of M13 bacteriophage.

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Emily M Zygiel

Full Text Available M13 and other members of the Ff class of filamentous bacteriophages have been extensively employed in myriad applications. The Ph.D. series of phage-displayed peptide libraries were constructed from the M13-based vector M13KE. As a direct descendent of M13mp19, M13KE contains the lacZα insert in the intergenic region between genes IV and II, where it interrupts the replication enhancer of the (+ strand origin. Phage carrying this 816-nucleotide insert are viable, but propagate in E. coli at a reduced rate compared to wild-type M13 phage, presumably due to a replication defect caused by the insert. We have previously reported thirteen compensatory mutations in the 5'-untranslated region of gene II, which encodes the replication initiator protein gIIp. Here we report several additional mutations in M13KE that restore a wild-type propagation rate. Several clones from constrained-loop variable peptide libraries were found to have ejected the majority of lacZα gene in order to reconstruct the replication enhancer, albeit with a small scar. In addition, new point mutations in the gene II 5'-untranslated region or the gene IV coding sequence have been spontaneously observed or synthetically engineered. Through phage propagation assays, we demonstrate that all these genetic modifications compensate for the replication defect in M13KE and restore the wild-type propagation rate. We discuss the mechanisms by which the insertion and ejection of the lacZα gene, as well as the mutations in the regulatory region of gene II, influence the efficiency of replication initiation at the (+ strand origin. We also examine the presence and relevance of fast-propagating mutants in phage-displayed peptide libraries.

Bird communities of contrasting semi-natural habitats of Lac bay, Bonaire, during the fall migration season, 2011

NARCIS (Netherlands)

Debrot, A.O.; Bemmelen, van R.S.A.; Ligon, J.

2013-01-01

The mangrove and seagrass lagoon of Lac Bay on Bonaire covers an area of roughly 700 ha. It is home to endangered green sea turtles, Chelonia mydas, and the Caribbean queen conch, Strombus gigas, and is a roosting and breeding area for several birds. Based on its nature values this 7 km2 bay has

Intelligent Local Avoided Collision (iLAC) MAC Protocol for Very High Speed Wireless Network

Science.gov (United States)

Hieu, Dinh Chi; Masuda, Akeo; Rabarijaona, Verotiana Hanitriniala; Shimamoto, Shigeru

Future wireless communication systems aim at very high data rates. As the medium access control (MAC) protocol plays the central role in determining the overall performance of the wireless system, designing a suitable MAC protocol is critical to fully exploit the benefit of high speed transmission that the physical layer (PHY) offers. In the latest 802.11n standard [2], the problem of long overhead has been addressed adequately but the issue of excessive colliding transmissions, especially in congested situation, remains untouched. The procedure of setting the backoff value is the heart of the 802.11 distributed coordination function (DCF) to avoid collision in which each station makes its own decision on how to avoid collision in the next transmission. However, collision avoidance is a problem that can not be solved by a single station. In this paper, we introduce a new MAC protocol called Intelligent Local Avoided Collision (iLAC) that redefines individual rationality in choosing the backoff counter value to avoid a colliding transmission. The distinguishing feature of iLAC is that it fundamentally changes this decision making process from collision avoidance to collaborative collision prevention. As a result, stations can avoid colliding transmissions with much greater precision. Analytical solution confirms the validity of this proposal and simulation results show that the proposed algorithm outperforms the conventional algorithms by a large margin.

Influence of Mining Pollution on Metal Bioaccumulation and Biomarker Responses in Cave Dwelling Fish, Clarias gariepinus.

Science.gov (United States)

du Preez, Gerhard; Wepener, Victor

2016-07-01

Cave ecosystems remain largely unstudied and risk being severely degraded as a result of anthropogenic activities. The Wonderfontein Cave, situated in the extensive gold mining region of the Witwatersrand Basin, is one such system that hosts a population of Clarias gariepinus, which is exposed to the influx of polluted mine water from the Wonderfontein Spruit River. The aim of this study was to investigate the bioaccumulation of metals, as well as relevant biomarkers, in C. gariepinus specimens sampled from the Wonderfontein Cave during high (April 2013) and low (September 2013) flow surveys. Results were also compared to a surface population associated with the Wonderfontein Spruit River. There were temporal differences in metal bioaccumulation patterns and this was attributed to the lack of dilution during the low flow period. Metals associated with acid mine drainage, i.e. Co, Mn and Zn were significantly higher in the Wonderfontein Cave population and were reflected in an increase in oxidative stress biomarkers (catalase, protein carbonyls and superoxide dismutase) and the induction of metallothionein, a biomarker of metal exposure. The surface population was exposed to metals associated with geological weathering processes, i.e. Fe and Al.

Survival strategies of sharptooth catfish Clarias gariepinus in desiccating pans in the northern Kruger National Park

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B.C.W. Van der Waal

1998-08-01

Full Text Available Observations in drying out pans showed that small (26-37 cm sharptooth catfish (Clarias gariepinus can hide at the bottom of small pools filled with sticky mud whereas larger fish stay afloat at the surface in larger pools with sloppy mud, where they easily become prey or succumb to heat stress. The inability of larger fish to keep down in the sloppy mud of up to 40 cm depth is the result of their large bulk and high density of the mud. This may indicate a survival advantage for smaller fish in the final dry-out phase of pools and is supported by the presence of only small fish remains in the last drying up pools of dry pans. Another adaptation of smaller fish includes the temporary congregation outside the water enabling concealment under dense vegetation as a means to escape adverse environmental conditions, including high water temperatures and avian predation. The advantage small fish have over larger catfish under these extreme conditions may explain why catfish are known to show a wide variation in growth rate under natural and aquaculture conditions.

An Analysis of Light Periods of BL Lac Object S5 0716+714 with the MUSIC Algorithm

Science.gov (United States)

Tang, Jie

2012-07-01

The multiple signal classification (MUSIC) algorithm is introduced to the estimation of light periods of BL Lac objects. The principle of the MUSIC algorithm is given, together with a testing on its spectral resolution by using a simulative signal. From a lot of literature, we have collected a large number of effective observational data of the BL Lac object S5 0716+714 in the three optical wavebands V, R, and I from 1994 to 2008. The light periods of S5 0716+714 are obtained by means of the MUSIC algorithm and average periodogram algorithm, respectively. It is found that there exist two major periodic components, one is the period of (3.33±0.08) yr, another is the period of (1.24±0.01) yr. The comparison of the performances of periodicity analysis of two algorithms indicates that the MUSIC algorithm has a smaller requirement on the sample length, as well as a good spectral resolution and anti-noise ability, to improve the accuracy of periodicity analysis in the case of short sample length.

Ovipositional Deterrence of Methanolic and Etherial Extracts of Five Plants to the Cowpea Bruchid, Callosobruchus maculatus (F. (Coleoptera: Bruchidae

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E.A. Elhag

1999-06-01

Full Text Available Methanol and diethyl ether extracts of Harmal, Rhazya stricta Decne.; neem seed kernels, Azadirachta indica A.Juss; cloves, Syzygeum aromarticum (L.; citrus peel and Ramram, Heliotropium bacciferum (Forssk- were evaluated for their deterrence to oviposition by Callosobruchus maculatus (F. on chickpeas in choice tests. Both extracts of all materials significantly reduced oviposition on treated seeds. Maximum deterrent effects (91.8% were obtained in the neem seed methanol extract at 0.5% concentration, citrus peel O. l% ether extract (90.9%, R stricta 0.5% methanol extract (83.9%, and clove 0. 1% ether extract (80.0%. Methanol extracts of neem seeds and R. stricta evoked higher deterrent effects than their etherial extracts, whereas the responses for cloves and citrus peel were more pronounced in their ether extracts. H. bacirferum % deterrency due to both types of extracts were practically identical. The results encourage future incorporation of such plant extracts as ovipositional deterrents in stored-product lPM programmes.

Influence of gamma radiation on oviposition and egg viability of Callosobruchus maculatus F. and grain loss in mungbean storage

International Nuclear Information System (INIS)

Dongre, T.K.; Rananavare, H.D.; Padwal Desai, S.R.

1997-01-01

Influence of gamma radiation on reproductive potential of Callosobruchus maculatus F. was studied by exposing them to 10, 30 and 50 Gy of radiation. Radiation at pupal stage was more effective in arresting egg laying and its further development. The dose of 50 Gy induced complete infertility in males when they were irradiated at pupal stage and only partial infertility was induced when irradiated at adult stage. In case of females whether irradiated at pupal or adult stage the dose of 50 Gy was sufficient to induce complete infertility. In order to assess the requirement of radiation doses for preventing the insect multiplication and subsequent damage in storage, mungbean samples with various developmental stages of insect were exposed to radiation at 50, 100 and 150 Gy. After three months of storage no grain damage was noticed when grains infested with different insect stages were irradiated with the dose of 100 or 150 Gy. (author)

Radio emission from quasars and BL Lac objects by coherent plasma oscillation and stimulated Compton scattering

International Nuclear Information System (INIS)

Colgate, S.A.; Petschek, A.G.

1978-01-01

The full radiation spectrum of quasars and BL Lac objects is interpreted as due to a dependent combination of a soft plasma oscillation source at 2ν/sub P/ and bremsstrahlung. Previous work of the plasma oscillation radiation is extended into the radio part of the spectrum and it is shown how the high brightness temperature observations of BL Lac objects [kT/sub b/ (100 MHz) approximate = 3 x 10 5 mc 2 ] are a reasonable consequence of a lower external plasma density and ejection as required for the observed lack of emission lines. Two extreme cases are considered, the one where the plasma oscillations are suddenly extinguished and only stimulated Compton scattering remains and a second case of a constant source of plasma oscillations but a graded surface density. The first case gives 1/100 of the required brightness temperature and the second gives 100 times too large a brightness temperature and also a x 10 too large a radius. It is believed reasonable to invoke a combination of both processes to explain the observed radio spectrum. This model circumvents the self-Compton x-ray flux difficulty of incoherent synchrotron emission

Hydrogen production by Escherichia coli {delta}hycA {delta}lacI using cheese whey as substrate

Energy Technology Data Exchange (ETDEWEB)

Rosales-Colunga, Luis Manuel; Ordonez, Leandro G.; De Leon-Rodriguez, Antonio (Division de Biologia Molecular, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Col. Lomas 4a secc. CP 78216, San Luis Potosi, SLP. Mexico); Razo-Flores, Elias; Alatriste-Mondragon, Felipe (Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Col. Lomas 4a secc. CP 78216, San Luis Potosi, SLP. Mexico)

2010-01-15

This study reports a fermentative hydrogen production by Escherichia coli using cheese whey as substrate. To improve the biohydrogen production, an E. coli {delta}hycA {delta}lacI strain (WDHL) was constructed. The absence of hycA and lacI genes had a positive effect on the biohydrogen production. The strain produced 22% more biohydrogen in a shorter time than the wild-type (WT) strain. A Box-Behnken experimental design was used to optimize pH, temperature and substrate concentration. The optimal initial conditions for biohydrogen production by WDHL strain were pH 7.5, 37 C and 20 g/L of cheese whey. The specific production rate was improved from 3.29 mL H{sub 2}/optical density at 600 nm (OD{sub 600nm}) unit-h produced by WDHL under non-optimal conditions to 5.88 mL H{sub 2}/OD{sub 600nm} unit-h under optimal conditions. Using optimal initial conditions, galactose can be metabolized by WDHL strain. The maximum yield obtained was 2.74 mol H{sub 2}/mol lactose consumed, which is comparable with the yield reached in other hydrogen production processes with Clostridium sp. or mixed cultures. (author)

Déclin et restauration de la population de truites lacustres (Salmo trutta lacustris L. du lac de Constance

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RUHLÉ C.

1990-10-01

Full Text Available Le déclin de la population de truites migratrices du lac de Constance a débuté vers 1950 quand un barrage a été construit sur le Rhin, affluent principal de ce lac, coupant ainsi l'accès aux plus importantes frayères. Ceci a suffi de prétexte pour renoncer à une longueur de capture garantissant la reproduction naturelle. Par la suite, la population en train de diminuer a servi de justification pour des déversements importants de truites arc-en-ciel. Un désintérêt croissant pour le maintien de frayères dans les affluents secondaires a, finalement, contribué à la baisse des captures de 12.000 kg à 3.000 kg entre 1950 et 1980.Les mesures réalisées au cours des dernières années pour restaurer la population de truites lacustres ont du succès. Il s'agit surtout de : — la détermination d'une nouvelle longueur de capture ainsi que de périodes de protection respectant la reproduction des truites migrant à longue et à courte distance,— l'élevage de stocks de géniteurs, — les déversements forcés et effectués surtout en affluents (au lieu du lac,— l'interdiction d'immersions de truites arc-en-ciel,— l'abolition de barrages. Le succès se manifeste par un nombre croissant de truites observées frayant dans les affluents ainsi que par des captures de plus en plus nombreuses faites par la pêche professionnelle.

Morphological studies on the Gaseous Chambers of the African-Catfish (Clarias gariepinus

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Eman A. Eshra

2015-04-01

Full Text Available This study aimed to find out the morpho-functional correlations of supra-branchial gaseous chambers (SC and gas bladder (GB in Clarias gariepinus. Gross, and Histological observations were made on ten different ontogenetic stages ranged from 10 mm SL (Standard length to 100 mm SL, and mature fish 330 mm-333 mm SL. Computed tomography (CT was performed on five mature fishes at 130 K Volt and 80 Ma, different CT windows were adjusted as follows: Soft tissue (WL: 40, WW: 300, Bone (2000: 400, and Air-chambers (-600:1200. Each SC lodged mid-constricted membranous sac, communicated to gill cavity via single opening. The GB was an oval sac surrounded by incomplete bony capsule, it touched the skin laterally, otic capsule medially and SC anteriorly. The SC membrane was three layered with a gill like mucosa (respiratory mucosa; GB has an inner layer of simple squamous epithelium and an outer layer of dense irregular connective tissue. Collectively, the larval stages were adult like, but differ in proportions; in stages from 10 to 26 mm, SC adventitia was ill defined or absent and SC musculosa was well developed relatively to the total thickness of the membrane. In CT images, there was a clear communication between the otic capsule and GB at the level of anterior-medial fissures of complex vertebra; disc–shaped fat pads appeared as hypodense bilateral areas dorso-medial to GB and caudo-posterior to SC. Results Concluded that GB and SC had an accessory auditory role related to their anatomical structure, position and communications.

Stress and Welfare of African Catfish (Clarias gariepinus Burchell, 1822 in a Coupled Aquaponic System

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Björn Baßmann

2017-07-01

Full Text Available African catfish (Clarias gariepinus were investigated for physiological stress parameters to assess the influence of different cultivation techniques on fish welfare. The fish were reared in two conceptually identical recirculating aquaculture systems (RAS constructed in a greenhouse. One system was combined with a floating raft hydroponic unit to culture cucumbers (Cucumis sativus only using the process water. The second system remained without the plant cultivation unit and functioned as the control. Water quality was monitored regularly by measuring dissolved nutrients and physical water parameters. During 87 days, a total of 71 fish from each system (n = 142 were studied, with a final sampling of all fish (n = 107 at the end of the experiment. Blood from the caudal vein was analyzed for the stress hormone cortisol and the glucose concentration. In addition, fish were investigated for external injuries on their skin, fins and barbels. The results demonstrate that the system design had no influence on fish mortalities and growth rates. Furthermore, cortisol and blood glucose levels did not differ significantly between the two systems. However, the number of external injuries was significantly lower in the aquaponics, providing evidence that co-cultivation of fish and plants might offer benefits to the welfare of the fish.

Efecto de la temperatura en la sobrevivencia embrionaria del puye Galaxias maculatus (Jenyns, 1842

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Juan Bariles

2013-11-01

Full Text Available Se evaluó el efecto de seis temperaturas constantes en la sobrevivencia embrionaria, periodo embrionario y periodo de eclosión de Galaxias maculatus de 7 a 22°C, en condiciones de laboratorio. Los resultados de la sobrevivencia embrionaria fueron: 90,6 ± 2,0; 88,7 ± 8,6; 87,7 ± 0,7; 89,7 ± 4,2; 70,0 ± 5,6 y 49,5 ± 7,4% a temperaturas de 7, 10, 13, 16, 19 y 22°C. Exceptuando la temperatura de 22°C, no hay diferencias significativas entre ellas (P > 0,05. Estos resultados caracterizan al embrión como euritérmico independientemente de ser una especie de aguas subantárticas. En relación al periodo embrionario (tH50%, los resultados fueron de 40,8 ± 0,6; 27,0 ± 0,0; 17,3 ± 0,6; 16,3 ± 0,6 y 13,3 ± 0,6 días a temperaturas de 7, 10, 13, 16 y 19°C respectivamente, con diferencias significativas entre ellas (P 87,7%, periodos embrionarios <27 días y periodos de eclosión <6,3 días. Estos resultados permitirán optimizar la sobrevivencia embrionaria y el eventual cultivo de la especie para fines comerciales o de repoblamiento.

Phylogeography in Galaxias maculatus (Jenyns, 1848 along Two Biogeographical Provinces in the Chilean Coast.

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Claudio A González-Wevar

Full Text Available Major geologic and climatic changes during the Quaternary exerted a major role in shaping past and contemporary distribution of genetic diversity and structure of aquatic organisms in southern South America. In fact, the northern glacial limit along the Pacific coast, an area of major environmental changes in terms of topography, currents, and water salinity, represents a major biogeographic transition for marine and freshwater species. We used mitochondrial DNA sequences (D-loop to investigate the consequences of Quaternary glacial cycles over the pattern of genetic diversity and structure of G. maculatus (Pisces: Galaxiidae along two biogeographical provinces in the Chilean coast. Extreme levels of genetic diversity and strong phylogeographic structure characterize the species suggesting a low amount of influence of the last glacial cycle over its demography. However, we recognized contrasting patterns of genetic diversity and structure between main biogeographical areas here analyzed. Along the Intermediate Area (38°-41° S each estuarine population constitutes a different unit. In contrast, Magellanic populations (43°-53° S exhibited low levels of genetic differentiation. Contrasting patterns of genetic diversity and structure recorded in the species between the analyzed biogeographic areas are consistent with the marked differences in abiotic factors (i.e., different coastal configurations, Quaternary glacial histories, and oceanographic regimes and to inherent characteristics of the species (i.e., salt-tolerance, physiology, and reproductive behavior.

Phylogeography in Galaxias maculatus (Jenyns, 1848) along Two Biogeographical Provinces in the Chilean Coast

Science.gov (United States)

González-Wevar, Claudio A.; Salinas, Pilar; Hüne, Mathias; Segovia, Nicolás I.; Vargas-Chacoff, Luis; Astorga, Marcela; Cañete, Juan I.; Poulin, Elie

2015-01-01

Major geologic and climatic changes during the Quaternary exerted a major role in shaping past and contemporary distribution of genetic diversity and structure of aquatic organisms in southern South America. In fact, the northern glacial limit along the Pacific coast, an area of major environmental changes in terms of topography, currents, and water salinity, represents a major biogeographic transition for marine and freshwater species. We used mitochondrial DNA sequences (D-loop) to investigate the consequences of Quaternary glacial cycles over the pattern of genetic diversity and structure of G. maculatus (Pisces: Galaxiidae) along two biogeographical provinces in the Chilean coast. Extreme levels of genetic diversity and strong phylogeographic structure characterize the species suggesting a low amount of influence of the last glacial cycle over its demography. However, we recognized contrasting patterns of genetic diversity and structure between main biogeographical areas here analyzed. Along the Intermediate Area (38°–41° S) each estuarine population constitutes a different unit. In contrast, Magellanic populations (43°–53° S) exhibited low levels of genetic differentiation. Contrasting patterns of genetic diversity and structure recorded in the species between the analyzed biogeographic areas are consistent with the marked differences in abiotic factors (i.e., different coastal configurations, Quaternary glacial histories, and oceanographic regimes) and to inherent characteristics of the species (i.e., salt-tolerance, physiology, and reproductive behavior). PMID:26161896

78 FR 3911 - Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN; Final Comprehensive...

Science.gov (United States)

2013-01-17

... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R3-R-2012-N259; FXRS1265030000-134-FF03R06000] Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN; Final Comprehensive... significant impact (FONSI) for the environmental assessment (EA) for Big Stone National Wildlife Refuge...

Deposition mechanism and microstructure of laser-assisted cold-sprayed (LACS) Al-12 wt.%Si coatings: effects of laser power

CSIR Research Space (South Africa)

Olakanmi, EO

2013-06-01

Full Text Available at the substrate and build up a coating. To circumvent the processing problems associated with cold-spray (CS) deposition of low-temperature, corrosion-resistant Al-12 wt.%Si coatings, a preliminary investigation detailing the effect of laser power on its LACS...

THE ABILITY OF FAST-GROWING TRANSGENIC AFRICAN CATFISH (Clarias gariepinus ON PREDATOR AVOIDANCE

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Huria Marnis

2016-12-01

Full Text Available Research Institute for Fish Breeding has produced transgenic African catfish (Clarias gariepinus containing stripped catfish growth hormone gene (PccBA-PhGH with growth 19.86% faster than that of non-transgenic fish. This fish has high potential to be released and utilized for fish farming sector to increase national production. However, there is not yet information about environmental risk of this fish. One of the major fitness traits determining potential environmental risk is predator avoidance. This study aimed to determine the predator avoidance ability of transgenic African catfish in an experimental laboratory condition. In this study, thirty five individuals each of transgenic and non-transgenic with body weight of about 0.1 ± 0.019 g were communally stocked in 60 cm x 40 cm x 40 cm aquarium with limited feeding frequency (ad libitum twice a day. One day after the fish were stocked, the predators were added to each aquarium. The non-transgenic and transgenic with body weight of 1.0 ± 0.024 g were stocked as predators as many as five individual in each aquarium. After approximately two weeks of predation, all remaining fish were collected for transgenic verification by PCR method. Genomic DNA was isolated from fin tissue of individually survivors. The results of this study showed that the transgenic fish had worse predator avoidance and lower cannibal than non-transgenic (P0.05 in limited food. The transgenic fish may have lower fitness than non-transgenic.

Generation of viable progeny from dead brooders of endangered catfish Clarias magur (Hamilton, 1822

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Sullip Kumar Majhi

2017-10-01

Full Text Available The obligatory air-breathing catfish Clarias magur is a prime candidate for aquaculture owing to its unique taste, high growth rate, and hardy nature. However, recently the IUCN has listed the species under the endangered category because the population has critically declined in the wild. The sexually mature C. magur brooders are often collected from their natural habitats for seed production in captivity. In many cases, the brooder dies due to handling injuries or confinement stress. In this study, we demonstrated that viable progeny could be generated from freshly dead sexually mature C. magur. Three hours after death, the gonads were excised, macroscopically examined and gamete viability was evaluated. Artificial fertilization was performed by mixing the sperm suspension with the eggs. Water was added after 1 min of mixing to activate the fertilization process. We observed 85%-93% fertilization success from gametes derived from dead donors as opposed to 90%-95% from those derived from live control donors. The embryos showed normal development and resulted in the generation of 88%-92% viable progeny, which was similar to the progeny derived from control donors (92%-93%. The results obtained in this study will have profound implications in enhancing the seed production of endangered C. magur and could potentially be applied to other key commercially or endangered fish species. Keywords: Biological sciences, Developmental biology, Zoology

The diluvial rains of Saguenay-Lac-Saint-Jean : status one year after

International Nuclear Information System (INIS)

Henri, N.; Beauchemin, G.; Alonso, M.; Gelinas, M.

1997-01-01

The status of damages and reconstruction in the Saguenay-Lac-Saint-Jean region, one year after the catastrophic torrential rain storm of July 1996 was presented. Numerous detailed maps and photographs of the principal washed-out, destroyed and damaged regions were presented, along with maps and photographs of the same areas after reconstruction, repair and landscaping. The maps show the different river beds, urban, and rural districts that were subjected to the catastrophic washouts, landslides and soil collapses. The report also includes a summary of the repair costs by municipal regions and the financial aid received by the region to help in the reconstruction effort. tabs., figs

Controle do caruncho Callosobruchus maculatus (Fabr., 1775 (Coleóptera: Bruchidae utilizando extratos de Piper nigrum L. (Piperaceae pelo método de vapor Control of cowpea weevil Callosobruchus maculatus (Fabr., 1775(Coleóptera: Bruchidae using extracts of Piper nigrum L. (Piperaceae by the steam method

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Silvana Alves de Almeida

2006-08-01

Full Text Available Considerando os prejuízos causados pelo inseto-praga Callosobruchus maculatus (Fabr., 1775 ao feijão Vigna unguiculata Walp. armazenado, com o presente trabalho objetivou-se avaliar a eficácia de extratos de Piper nigrum L. na mortalidade de adultos daquela espécie. O delineamento estatístico utilizado foi inteiramente ao acaso com quatro repetições e arranjo fatorial 3 x 5, constituído por três concentrações do extrato e cinco períodos de exposições dos extratos (5, 10, 15, 20 e 25 minutos. Utilizaram-se frutos secos triturados de P. nigrum para extração em percolador com solvente álcool etílico (70, 50 e 30%. Os extratos foram aplicados na forma de vapor, por meio de um compressor adaptado, para dentro de recipiente contendo 100 insetos. Os resultados permitiram concluir que a mortalidade dos insetos aumenta com o aumento do período de exposição aos extratos, e que todas as concentrações se mostraram eficientes, embora, em termos de valores absolutos, o extrato com 70% de álcool etílico foi o mais eficaz.Considering the damage caused by the insect pest Callosobruchus maculatus (Fabr., 1775 to stored Vigna unguiculata Walp beans, this work aimed to evaluate the effectiveness of extracts of Piper nigrum L. in the control of adults of the referred species. The statistical outline used was made at random with four repetitions and factorial arrangement 3 x 5, formed by three concentrations of the extract and five periods of exposure to the extracts (5, 10, 15, 20 and 25 minutes. P. nigrum grounded dry fruits were used for extraction , which was done with ethyl alcohol (70, 50 and 30%, using a percolator. The extracts were applied as steam, using an adapted compressor into a container having 100 insects. By the results it was possible to conclude that the mortality of the insects becomes higher as the period of exposure to the extracts is increased, and that all the concentrations were shown to be effective, although, in

A new species of Trichodina Ehrenberg, 1830 (Ciliophora: Trichodinidae) infecting farmed Clarias gariepinus (Burchell) (Siluriformes: Clariidae) in Cuba.

Science.gov (United States)

León, Fernando Lucas Prats; Pérez, Mercedes Martínez

2017-11-01

A new species of Trichodina Ehrenberg, 1830 collected from the skin and fins of farmed North African catfish Clarias gariepinus (Burchell) fingerlings, is described. The new species can be distinguished from other trichodinids by the characteristics of the adhesive disc, especially by the great number of denticles. Trichodina merciae n. sp. is morphologically similar to T. renicola (Mueller, 1931) and T. marplatensis Martorelli, Marcotegui & Alda, 2008, in the number of denticles, but differs in the morphometric data, denticle morphology, environment and location. Trichodina merciae n. sp. has broad sickle-shaped blades and thin, straight rays, while T. marplatensis has broad club-shaped blades and wide S-shaped rays. Besides, denticle length, blade length, ray length, width of central part and denticle span of the new species are greater than T. marplatensis. However, the diameter of denticle ring and the diameter of the central area in T. marplatensis is larger than the ones in T. merciae n. sp. This is the first record of freshwater ectoparasite trichodinid with an average number of denticles greater than 50.

Mutagenicity of the peroxisome proliferators clofibrate, Wyeth 14,643 and di-2-ethylhexyl phthalate in the lacZ plasmid-based transgenic mouse mutation assay

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Boerrigter Michaël

2004-01-01

Full Text Available Abstract Background Peroxisome proliferators are considered rodent carcinogens that are putative human non-carcinogens based on the presumed absence of direct genetic toxicity in rodent and human cells and the resistance of human cells to the induction of peroxisomes by peroxisome proliferators. The highly sensitive lacZ plasmid-based transgenic mouse mutation assay was employed to investigate the mutagenicity of several peroxisome proliferators based on several lines of evidence suggesting that these agents may in fact exert a genotoxic effect. Methods Male and female lacZ-plasmid based transgenic mice were treated at 4 months of age with 6 doses of 2,333 mg di-2-ethylhexyl phthalate (DHEP, 200 mg Wyeth-14,643, or 90 mg clofibrate per kg of bodyweight, respectively, over a two-week period. Control animals were treated with the respective vehicles only (35% propyl glycol for DEHP and Wyeth-14,643 treatment controls and sterile water for clofibrate treatment controls. The mutant frequency in liver, kidney and spleen DNA was determined as the proportion of retrieved mutant and wild-type lacZ plasmids expressed in Escherichia Coli C host cells employing a positive selection system for mutant plasmids. Results Exposure to DEHP or Wyeth-14,643 significantly increased the mutant frequency in liver, but not in kidney or spleen, of both female and male mice. Treatment with clofibrate did not lead to an increased mutant frequency in any of the organs studied. Conclusion The results indicate that some peroxisome proliferators display an organ-specific mutagenicity in lacZ plasmid-based transgenic mice consistent with historical observations of organ- and compound-specific carcinogenicity.

Polarization burst in the BL Lac object AO 0235 + 164

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Impey, C D; Brand, P W.J.L. [Edinburgh Univ. (UK). Dept. of Astronomy; Tapia, S [Steward Observatory, Tucson, AZ (USA)

1982-01-01

Simultaneous infrared and optical polarimetry and photometry have been obtained for AO 0235 + 164 covering a five night period. The object underwent a polarization burst during which the 2.2 ..mu..m polarization rose from 17.5 to 28.7 per cent and fell again to 14.9 per cent. At its peak the degree of optical polarization was 43.9 per cent, the highest linear polarization observed in a BL Lac object. The data show the degree of polarization to increase towards shorter wavelengths, and the effect is inconsistent with either dilution by a galactic component or simple one-component synchrotron models. The large changes in polarization are not accompanied by large changes in flux, a result which is difficult to explain using conventional models of these objects. Other implications of the luminosity, polarization and variability are discussed.

DNA adducts, mutant frequencies and mutation spectra in λlacZ transgenic mice treated with N-nitrosodimethylamine

NARCIS (Netherlands)

Souliotis, V.L.; Delft, J.H.M. van; Steenwinkel, M.-J.S.T.; Baan, R.A.; Kyrtopoulos, S.A.

1998-01-01

Groups of λlacZ transgenic mice were treated i.p. with N-nitrosodimethylamine (NDMA) as single doses of 5 mg/kg or 10 mg/kg or as 10 daily doses of 1 mg/kg and changes in DNA N7- or O6-methylguanine or the repair enzyme O6-alkylguanine-DNA alkyltransferase (AGT) were followed for up to 14 days in

Hopf Bifurcation and Delay-Induced Turing Instability in a Diffusive lac Operon Model

Science.gov (United States)

Cao, Xin; Song, Yongli; Zhang, Tonghua

In this paper, we investigate the dynamics of a lac operon model with delayed feedback and diffusion effect. If the system is without delay or the delay is small, the positive equilibrium is stable so that there are no spatial patterns formed; while the time delay is large enough the equilibrium becomes unstable so that rich spatiotemporal dynamics may occur. We have found that time delay can not only incur temporal oscillations but also induce imbalance in space. With different initial values, the system may have different spatial patterns, for instance, spirals with one head, four heads, nine heads, and even microspirals.

The role of laserpuncture exposure on gonad maturation mechanism of catfish (Clarias sp. through Ca2+, PKC and GABA neurotransmitter

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Pungky Slamet Wisnu Kusuma

2017-12-01

Full Text Available Laser puncture exposure at reproduction acupoint is proven to increase cellular activity like Ca2+ in the skin tissues. The aim of the study is to determine the role of laserpuncture exposure on gonad maturation by evaluating Ca2+ stimulation and PKC activity in skin tissue and the release of GABA from GABAergic neurons of the brain tissue of catfish (Clarias sp.. A total of 36 females and 36 males of 8–9-month old of F1 catfish broodstock Sangkuriang (female and Paiton (male. This study used Completely Randomized Design (CDR experimental method. Expression analysis was conducted using immunohistochemical staining with a streptavidinbiotin method with calcineurin kit, PKC kit, and GABA kit. The results showed that laserpuncture can stimulate calcineurin and PKC expression in skin tissue, and GABA expression in the brain tissue on the condition pre-spawn, spawn, and post-spawn (P < .05. It can be concluded that laserpuncture stimulates gonad maturation through Ca2+, PKC, and GABA neurotransmitter.

L'habitat à une échelle globale : importance respective de l'immigration et de l'extinction pour les peuplements de poissons des petits lacs

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TONN W. M.

1995-04-01

Full Text Available Les deux processus qui déterminent la structure des communautés dans les habitats insulaires sont l'immigration d'espèces vers une communauté et l'extinction de celles qui étaient présentes auparavant. Bien que l'immigration et l'extinction se produisent généralement à des échelles supérieures à celles qu'il est possible d'étudier avec des expériences plannifiées, les écologistes peuvent améliorer leur compréhension de ces processus par l'analyse des distributions observées ; l'isolation, le caractère discret et la réplication des systèmes insulaires présentent des avantages pour réaliser de telles analyses. Comme pour les communautés observées sur de vraies îles, la structure des peuplements de poissons dans les petits lacs forestiers est le résultat de l'immigration et de l'extinction. L'importance relative de ces processus peut dépendre des caractéristiques d'habitat des lacs et des espèces présentes, ainsi que du cadre régional et historique des lacs étudiés. Dans une région donnée, la composition des peuplements locaux de poissons peut être reliée à un ensemble particulier de conditions d'habitat et, dans la mesure où ces facteurs peuvent être liés à l'immigration et à l'extinction, il devrait être possible d'analyser les relations peuplement-environnement pour en déduire l'importance relative de ces processus dans la formation de peuplements locaux dans et entre les régions et les continents. Nous avons réalisé des analyses à large échelle des relations peuplement-environnement des petits lacs forestiers de quatre régions tempérées d'Europe et d'Amérique du Nord ; l'utilisation d'une série d'analyses canonique partielle des correspondances nous a permis de distinguer la variation due aux relations peuplements-environnement d'un ensemble de facteurs associés à l'immigration contre l'extinction. Les isolations passées et présentes varient selon les lacs et les régions, comme la

ASCA and Contemporaneous Ground-based Observations of the BL Lacertae Objects 1749+096 and 2200+420 (BL Lac)

International Nuclear Information System (INIS)

Sambruna, R.M.; Ghisellini, G.; Hooper, E.; Kollgaard, R.I.; Pesce, J.E.; Urry, C.M.

1999-01-01

We present ASCA observations of the radio-selected BL Lacertae objects 1749+096 (z=0.32) and 2200+420 (BL Lac, z=0.069) performed in 1995 September and November, respectively. The ASCA spectra of both sources can be described as a first approximation by a power law with photon index Γ∼2. This is flatter than for most X-ray endash selected BL Lacs observed with ASCA, in agreement with the predictions of current blazar unification models. While 1749+096 exhibits tentative evidence for spectral flattening at low energies, a concave continuum is detected for 2200+420: the steep low-energy component is consistent with the high-energy tail of the synchrotron emission responsible for the longer wavelengths, while the harder tail at higher energies is the onset of the Compton component. The two BL Lacs were observed with ground-based telescopes from radio to TeV energies contemporaneously with ASCA. The spectral energy distributions are consistent with synchrotron self-Compton emission from a single homogeneous region shortward of the IR/optical wavelengths, with a second component in the radio domain related to a more extended emission region. For 2200+420, comparing the 1995 November state with the optical/GeV flare of 1997 July, we find that models requiring inverse Compton scattering of external photons provide a viable mechanism for the production of the highest (GeV) energies during the flare. In particular, an increase of the external radiation density and of the power injected in the jet can reproduce the flat γ-ray continuum observed in 1997 July. A directly testable prediction of this model is that the line luminosity in 2200+420 should vary shortly after (∼1 month) a nonthermal synchrotron flare. copyright copyright 1999. The American Astronomical Society

Embryonic and larvae development of reciprocal crosses between Pangasianodon hypophthalmus (Sauvage, 1878 and Clarias gariepinus (Burchell, 1822

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V.T. Okomoda

2017-12-01

Full Text Available The egg and larval development of reciprocal crosses of Pangasianodon hypophthalmus (Sauvage, 1878 and Clarias gariepinus (Burchell, 1822 were studied under laboratory conditions. Crosses between ♀C. gariepinus × ♂P. hypophthalmus (Clariothalmus and ♀P. hypophthalmus × ♂C. gariepinus (Pangapinus had embryonic stages similar to those of the pure sib, however, unequal cell cleavages were notable in the early development of both crosses, hence, leading to different forms of deformities. The critical stage where highest mortality occurred during the embryogenesis was the somite (21.68% and hatching (48.1% stages (respectively for the Clariothalmus and Pangapinus. However, both crosses produced viable larvae (60.21 vs 13.20% hatchability respectively, which survived (30.3 vs 2.1% respectively until the end of the study (2 weeks. The external morphological features of the larvae were completely formed by the 14th day after hatching. The body forms of the crosses at this time were either phenotypic intermediary of the parent species (92% of Clariothalmus or indistinguishable from the female parent (all Pangapinus and 8% of the Clariothalmus. This study thus laid the groundwork for further comparative studies on hybrid performance and characterization.

Water in the Cratonic Mantle: Insights from FTIR Data on Lac De Gras Xenoliths (Slave Craton, Canada)

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Peslier, Anne H.; Brandon, Alan D.; Schaffer, Lillian Aurora; O'Reilly, Suzanne Yvette; Griffin, William L.; Morris, Richard V.; Graff, Trevor G.; Agresti, David G.

2014-01-01

The mantle lithosphere beneath the cratonic part of continents is the deepest (> 200 km) and oldest (>2-3 Ga) on Earth, remaining a conundrum as to how these cratonic roots could have resisted delamination by asthenospheric convection over time. Water, or trace H incorporated in mineral defects, could be a key player in the evolution of continental lithosphere because it influences melting and rheology of the mantle. Mantle xenoliths from the Lac de Gras kimberlite in the Slave craton were analyzed by FTIR. The cratonic mantle beneath Lac de Gras is stratified with shallow (water contents extending to higher values than those from the shallow ones. The FTIR spectra of olivines from the shallow samples have more prominent Group II OH bands compared to the olivines from the deep samples, consistent with a more oxidized mantle environment. The range of olivine water content is similar to that observed in Kaapvaal craton peridotites at the same depths (129-184 km) but does not extend to as high values as those from Udachnaya (Siberian craton). The Slave, Kaapvaal and Siberian cratons will be compared in terms of water content distribution, controls and role in cratonic root longevity.

p21-LacZ reporter mice reflect p53-dependent toxic insult

International Nuclear Information System (INIS)

Vasey, Douglas B.; Wolf, C. Roland; MacArtney, Thomas; Brown, Ken; Whitelaw, C. Bruce A.

2008-01-01

There is an urgent need to discover less toxic and more selective drugs to treat disease. The use of transgenic mice that report on toxic insult-induced transcription can provide a valuable tool in this regard. To exemplify this strategy, we have generated transgenic mice carrying a p21-LacZ transgene. Transgene activity reflected endogenous p21 gene activation in various tissues, displayed compound-specific spatial expression signatures in the brain and immune tissues and enabled p53-dependent and p53-independent responses to be identified. We discuss the application of these mice in delineating the molecular events in normal cellular growth and disease and for the evaluation of drug toxicity

The ultraviolet to X-ray continua of BL Lac objects

International Nuclear Information System (INIS)

George, I.M.; Warwick, R.S.; McHardy, I.M.

1988-01-01

The results from EXOSAT observations of three X-ray bright BL Lacertae objects, Mrk 501, 1218 + 304 and Mrk 180 are presented. All three sources have soft power-law X-ray spectra with low-energy cut-offs consistent with absorption in the line-of-sight gas column density through our own galaxy. The three objects also exhibit significant spectral variability in the X-ray band on time-scales ranging from a few days to a year. In each case, X-ray flux and spectral index appear to be correlated, in the sense that the X-ray spectrum hardens as the source brightens. The intrinsic ultraviolet to X-ray spectrum of these and several other X-ray bright BL Lac objects can be modelled as a power-law continuum of energy index ∼1.0 below about 0.1 keV, above which the spectral slope steepens. (author)

Preferential oxidation of linolenic acid compared to linoleic acid in the liver of catfish (Heteropneustes fossilis and Clarias batrachus)

International Nuclear Information System (INIS)

Bandyopadhyay, G.K.; Dutta, J.; Ghosh, S.

1982-01-01

The fate of [1(- 14 C] linoleic acid and [1( 14 C] linolenic acid in the liver slices and also in the liver tissues of live carnivorous catfish, Heteropneustes fossilis and Clarias batrachus, was studied. Incorporation of the fatty acids into different lipid classes in the live fish differed greatly from the tissue slices, indicating certain physiological control operative in vivo. The extent of desaturation and chain elongation of linoleic and linolenic acids into long-chain polyunsaturated fatty acids was low. Linolenic acid was oxidized (thus labeling the saturated fatty acid with liberated 14 C-acetyl-CoA) in preference to linoleic acid, and this oxidation also seemed to be under physiological control since both of the fatty acids were poorly oxidized in the tissue slices and in the killed fish. These fish can therefore recognize the difference in the acyl chain structures of linoleate and linolenate. The higher oxidation of linolenic acid and poor capacity for its conversion to longer chain, highly unsaturated derivatives indicates a higher demand for the dietary supply of these essential fatty acids in these two species

Largemouth bass (Micropterus salmoides Lacépède): reproduction management and larval rearing in Italy

OpenAIRE

A. Dees; P. Melotti; R. Vicenzi; A. Roncarati

2010-01-01

Micropterus salmoides (Lacépède) was originally present into the waters of the eastern United States of America, northern Mexico and southern Canada. This species can be distinguished from the other black basses by the fact that its mouth extends to and beyond the edge of the eye and the first and the second dorsal fins are almost separated by a deep dip and there are no scales on the soft rayed of the second dorsal fin.

Quasi-simultaneous observations of the BL Lac object MK 501 in X-ray, UV, visible, IR and radio frequencies

Science.gov (United States)

Kondo, D. M.; Worrall, D. M.; Mushotzky, R. F.; Hackney, R. L.; Hackney, K. H.; Oke, J. B.; Yee, H.; Neugebauer, G.; Matthews, K.; Feldman, P. A.

1980-01-01

Quasi-simultaneous observations of the BL Lacertae (Lac) objects MK 501 were performed for the first time at X-ray, ultraviolet, visible, infrared, and radio frequencies. The observed spectral slope from the X-ray to UV regions is positive and continuous, but that from the mid UV to visible light region becomes gradually flat and possibly turns down toward lower frequencies; the optical radio emission can not be accounted for by a single power law. Several theoretical models were considered for the emission mechanism. A quantitative comparison was performed with the synchrotron-self-Compton model; the total spectrum is found consistent with this model. The spectrum from visible light to X-ray is consistent with synchrotron radiation or with inverse-Compton scattering by a hot thermal cloud of electrons. The continuity of the spectral slope from X-ray to UV implied by the current data suggests that the previous estimates of the total luminosity of this BL Lac object is underestimated by a factor of about three or four.

Lactose carrier protein of Escherichia coli. Structure and expression of plasmids carrying the Y gene of the lac operon.

Science.gov (United States)

Teather, R M; Bramhall, J; Riede, I; Wright, J K; Fürst, M; Aichele, G; Wilhelm, U; Overath, P

1980-01-01

The previously described hybrid plasmid pC7 which carries lacI+O+delta(Z)Y+A+ on a 12.3 X 10(6)-Mr DNA fragment [Teather et al. (1978) Mol. Gen. Genet. 159, 239-248] was partially digested with the restriction endonuclease EcoRI under conditions reducing the recognition sequence to d(A-A-T-T) and ligated to the vector pB322. lac Y-carrying inserts of various sized (Mr 1.5-4.7 X 10(6)) were obtained. Hybrid plasmid pTE18 (2300-base-pair insert) carries part of the I (repressor) gene, the promotor-operator region, part of the Z (beta-galactosidase) gene, the Y (lactose carrier) gene and part of the A (transacetylase) gene. Upon induction of pTE18-harbouring strains the Y-gene product is expressed at a nearly constant rate for several generations and accumulates to a level of 12-16% of the total cytoplasmic membrane protein. Integration into the membrane leads to active carrier as judged by binding and transport measurements.

Thermal cracking in Lac du Bonnet granite during slow heating to 205 degrees celsius

International Nuclear Information System (INIS)

Chernis, P.J.; Robertson, P.B.

1993-09-01

Acoustic emissions (AE) were recorded as drill core samples of Lac du Bonnet granite were slowly heated to between 66 and 205 degrees celsius to evaluate the effects of temperature on the properties of rock samples. Longitudinal and shear velocities of the samples were measured, and Young's moduli, shear moduli and Poisson's ratios were calculated. No significant AE activity was detected until temperatures reached approximately 73-80 degrees celsius. Above this 'threshold' temperature, calculated rock properties decreased, and at 205 degrees celsius calculated Young's modulus, shear modulus, and Poisson's ratio were reduced by 30, 26, and 29% respectively

VLBA Observations of Low Luminosity Flat Spectrum Radio Galaxies and BL Lac Objects: Polarisation Properties

Science.gov (United States)

Bondi, M.; Dallacasa, D.; Stanghellini, C.; Marchã, M. J. M.

We obtained two-epoch VLBA observations at 5 GHz of a list of radio galaxies drawn from the 200 mJy sample (Marcha et al. 1996). The objects selected for milli-arcsecond scale observations are classified, on the basis of their optical spectroscopic and polarimetric properties, as BL Lac objects, normal weak line radio galaxies, broad line radio galaxies, and transition objects (those with intermediate properties). We present preliminary results on the radio polarization properties, on the milli-arcsecond scale, of objects with different optical properties and discuss structural variations detected from the two epochs.

Interplay of protein and DNA structure revealed in simulations of the lac operon.

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Luke Czapla

Full Text Available The E. coli Lac repressor is the classic textbook example of a protein that attaches to widely spaced sites along a genome and forces the intervening DNA into a loop. The short loops implicated in the regulation of the lac operon suggest the involvement of factors other than DNA and repressor in gene control. The molecular simulations presented here examine two likely structural contributions to the in-vivo looping of bacterial DNA: the distortions of the double helix introduced upon association of the highly abundant, nonspecific nucleoid protein HU and the large-scale deformations of the repressor detected in low-resolution experiments. The computations take account of the three-dimensional arrangements of nucleotides and amino acids found in crystal structures of DNA with the two proteins, the natural rest state and deformational properties of protein-free DNA, and the constraints on looping imposed by the conformation of the repressor and the orientation of bound DNA. The predicted looping propensities capture the complex, chain-length-dependent variation in repression efficacy extracted from gene expression studies and in vitro experiments and reveal unexpected chain-length-dependent variations in the uptake of HU, the deformation of repressor, and the folding of DNA. Both the opening of repressor and the presence of HU, at levels approximating those found in vivo, enhance the probability of loop formation. HU affects the global organization of the repressor and the opening of repressor influences the levels of HU binding to DNA. The length of the loop determines whether the DNA adopts antiparallel or parallel orientations on the repressor, whether the repressor is opened or closed, and how many HU molecules bind to the loop. The collective behavior of proteins and DNA is greater than the sum of the parts and hints of ways in which multiple proteins may coordinate the packaging and processing of genetic information.

Interplay of protein and DNA structure revealed in simulations of the lac operon.

Science.gov (United States)

Czapla, Luke; Grosner, Michael A; Swigon, David; Olson, Wilma K

2013-01-01

The E. coli Lac repressor is the classic textbook example of a protein that attaches to widely spaced sites along a genome and forces the intervening DNA into a loop. The short loops implicated in the regulation of the lac operon suggest the involvement of factors other than DNA and repressor in gene control. The molecular simulations presented here examine two likely structural contributions to the in-vivo looping of bacterial DNA: the distortions of the double helix introduced upon association of the highly abundant, nonspecific nucleoid protein HU and the large-scale deformations of the repressor detected in low-resolution experiments. The computations take account of the three-dimensional arrangements of nucleotides and amino acids found in crystal structures of DNA with the two proteins, the natural rest state and deformational properties of protein-free DNA, and the constraints on looping imposed by the conformation of the repressor and the orientation of bound DNA. The predicted looping propensities capture the complex, chain-length-dependent variation in repression efficacy extracted from gene expression studies and in vitro experiments and reveal unexpected chain-length-dependent variations in the uptake of HU, the deformation of repressor, and the folding of DNA. Both the opening of repressor and the presence of HU, at levels approximating those found in vivo, enhance the probability of loop formation. HU affects the global organization of the repressor and the opening of repressor influences the levels of HU binding to DNA. The length of the loop determines whether the DNA adopts antiparallel or parallel orientations on the repressor, whether the repressor is opened or closed, and how many HU molecules bind to the loop. The collective behavior of proteins and DNA is greater than the sum of the parts and hints of ways in which multiple proteins may coordinate the packaging and processing of genetic information.

Largemouth bass (Micropterus salmoides Lacépède: reproduction management and larval rearing in Italy

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A. Dees

2010-01-01

Full Text Available Micropterus salmoides (Lacépède was originally present into the waters of the eastern United States of America, northern Mexico and southern Canada. This species can be distinguished from the other black basses by the fact that its mouth extends to and beyond the edge of the eye and the first and the second dorsal fins are almost separated by a deep dip and there are no scales on the soft rayed of the second dorsal fin.

Croissance et alimentation des larves de corégones (Coregonus lavaretus dans le lac d'Annecy de mars à avril 1996

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CRETENOY L.

1997-04-01

Full Text Available La capture de plus de 400 larves de Coregonus lavaretus à 7 dates différentes dans le lac d'Annecy de mars à avril 1996 a permis d'étudier conjointement leur croissance et l'évolution de leur régime alimentaire. Les larves capturées ont une taille comprise entre 8,5 et 20 mm et un stade larvaire allant de 0 à 4, ces deux paramètres étant fortement liés. À mesure qu'elles grandissent, les larves qui consomment d'abord préférentiellement les stades larvaires des copépodes, puis leurs stades adultes, se nourrissent ensuite majoritairement de cladocères. La comparaison des structures de taille des proies ingérées et du zooplancton présent dans le lac conduit à évoquer la notion d'expérience acquise par les larves pour expliquer cette dérive alimentaire.

White Mulberry (Morus alba Foliage Methanolic Extract Can Alleviate Aeromonas hydrophila Infection in African Catfish (Clarias gariepinus

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Atefeh Sheikhlar

2014-01-01

Full Text Available Two experiments were simultaneously conducted with Morus alba (white mulberry foliage extract (MFE as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp. in African catfish (Clarias gariepinus. In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC, albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM. Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish.

White Mulberry (Morus alba) Foliage Methanolic Extract Can Alleviate Aeromonas hydrophila Infection in African Catfish (Clarias gariepinus)

Science.gov (United States)

Sheikhlar, Atefeh; Alimon, Abd Razk; Daud, Hassan; Saad, Chee R.; Webster, Carl D.; Meng, Goh Yong

2014-01-01

Two experiments were simultaneously conducted with Morus alba (white mulberry) foliage extract (MFE) as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp.) in African catfish (Clarias gariepinus). In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM) of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC), albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM). Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish. PMID:25574488

White mulberry (Morus alba) foliage methanolic extract can alleviate Aeromonas hydrophila infection in African catfish (Clarias gariepinus).

Science.gov (United States)

Sheikhlar, Atefeh; Alimon, Abd Razk; Daud, Hassan; Saad, Chee R; Webster, Carl D; Meng, Goh Yong; Ebrahimi, Mahdi

2014-01-01

Two experiments were simultaneously conducted with Morus alba (white mulberry) foliage extract (MFE) as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp.) in African catfish (Clarias gariepinus). In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM) of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC), albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM). Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish.

Digestibilidade e metabólitos sanguíneos de vacas da raça Holandesa superovuladas que receberam Lac100® ou linhaça em grão como fontes de gordura Digestibility and blood concentration of metabolites in superovulated dairy cows fed Lac100® or linseed as fat sources

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F.L.B. Cavalieri

2009-08-01

Full Text Available Foram avaliados os efeitos de duas fontes de gordura, Lac100® (Yakult, fonte de ácido graxo ômega-6, e linhaça em grão (Linum usitatissimum (LIN, fonte de ácido graxo ômega-3, sobre a digestibilidade aparente da matéria seca (DMS, proteína bruta (DPB, fibra em detergente neutro (DFDN, fibra em detergente ácido (DFDA e extrato etéreo (DEE, e concentrações sanguíneas de HDL, LDL, VLDL, colesterol, triglicerídeos, glicose, cálcio, fósforo, N-ureico e progesterona. Foram utilizadas 10 vacas da raça Holandesa em lactação, distribuídas nos dois tratamentos, em um delineamento estatístico inteiramente casualizado. Os animais alimentados com Lac100® apresentaram maiores valores de DFDN (57,44% vs. 50,80% e DEE (77,70% vs. 72,18% quando comparados aos alimentados com LIN. Os animais alimentados com Lac100® apresentaram maiores concentrações de LDL (111,00 vs. 45,46mg/dL, HDL (82,27 vs. 64,93mg/dL e colesterol total (203,60 vs. 116,13mg/dL e menor concentração de N-ureico (13,22 vs. 15,19mg/dL em relação aos animais alimentados com linhaça em grão. As concentrações sanguíneas de glicose, cálcio, fósforo e progesterona não foram alteradas. Os resultados sugerem que a fonte de gordura na dieta modifica a DFDN e a DEE e, as concentrações sanguíneas de LDL, HDL e colesterol total em vacas em lactação.The effect of two sources of fat, calcium salts of soybean oil, Lac100® (Yakult, a source of omega-6 fatty acids or whole flaxseed (Linum usitatissiumum, a source of omega-3 fatty acids were evaluated to determine the apparent digestibility of dry matter (DDM, crude protein (DCP, neutral detergent fiber (DNDF, acid detergent fiber (DADF, and ether extract (DEE; and blood concentrations of HDL, LDL, VLDL, cholesterol, triglycerides, glucose, calcium, phosphorus, N-urea, and progesterone. Ten lactating Holstein cows were allocated in two treatments and a completely randomized design was used. Cows fed Lac100® had higher

Tapeworms (Cestoda: Caryophyllidea), parasites of Clarias batrachus (Pisces: Siluriformes) in the Indomalayan region.

Science.gov (United States)

Ash, Anirban; Scholz, Tomáš; Oros, Mikuláš; Kar, Pradip Kumar

2011-06-01

Revision of monozoic cestodes (Caryophyllidea) parasitic in commercially important walking catfish Clarias batrachus (L.) in tropical Asia (Indomalayan zoogeographical region) was carried out, based on the evaluation of newly collected material from India, Indonesia, and Thailand, as well as a study of type specimens. Instead of the 59 nominal taxa of 15 genera from 3 caryophyllidean families previously described, only 8 species of the Lytocestidae are considered to be valid: Bovienia indica (Niyogi, Gupta and Agarwal, 1982) n. comb.; Bovienia raipurensis (Satpute and Agarwal, 1980) Mackiewicz, 1994; Bovienia serialis (Bovien, 1926) Fuhrmann, 1931; Djombangia penetrans Bovien, 1926; Lucknowia microcephala (Bovien, 1926) n. comb.; Lytocestus indicus (Moghe, 1925) Woodland 1926; Pseudocaryophyllaeus ritai Gupta and Singh, 1983; and Pseudocaryophyllaeus tenuicollis (Bovien, 1926) n. comb. All valid species are redescribed and SEM photomicrographs of their scolices and photomicrographs of their eggs are provided for the first time. Crescentovitus Murhar, 1963, Heeradevina Srivastav and Khare, 2005, Pseudobatrachus Pathak and Srivastav, 2005, Pseudobilobulata Srivastav and Lohia, 2002, Pseudoclariasis Pathak, 2002, and Pseudoinverta Pathak, 2002 are invalidated and 50 nominal species are newly synonymized, including 4 species described from other fish hosts. Taxonomic status of the remaining caryophyllidean taxa reported from C. batrachus (at least 6 taxa) could not be clarified because of the unavailability of their original descriptions. A key to identification of caryophyllidean tapeworms parasitic in C. batrachus is provided. To avoid current inflation of descriptions of invalid taxa, researchers are strongly encouraged to work only with well-fixed material; damaged, decomposed, or strongly flattened specimens should not be used for taxonomic studies, and type specimens must always be deposited in internationally recognized collections.

Multi-epoch intranight optical monitoring of eight radio-quiet BL Lac candidates

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Kumar, P.; Gopal-Krishna; Stalin, C. S.; Chand, H.; Srianand, R.; Petitjean, P.

2017-10-01

For a new sample of eight weak-line quasars (WLQs) we report a sensitive search in 20 intranight monitoring sessions, for blazar-like optical flux variations on hour-like and longer time-scale (day/month/year-like). The sample consists exclusively of the WLQs that are not radio-loud and either have been classified as 'radio-weak probable BL Lac candidates' and/or are known to have exhibited at least one episode of large, blazar-like optical variability. Whereas only a hint of intranight variability is seen for two of these WLQs, J104833.5+620305.0 (z = 0.219) and J133219.6+622715.9 (z = 3.15), statistically significant internight variability at a few per cent level is detected for three of the sources, including the radio-intermediate WLQ J133219.6+622715.9 (z = 3.15) and the well-known bona fide radio-quiet WLQs J121221.5+534128.0 (z = 3.10) and WLQ J153259.9-003944.1 (z = 4.62). In the rest frame, this variability is intraday and in the far-ultraviolet band. On the time-scale of a decade, we find for three of the WLQs large brightness changes, amounting to 1.655 ± 0.009, 0.163 ± 0.010 and 0.144 ± 0.018 mag, for J104833.5+620305.0, J123743.1+630144.9 and J232428.4+144324.4, respectively. Whereas the latter two are confirmed radio-quiet WLQs, the extragalactic nature of J104833.5+620305.0 remains to be well established, thanks to the absence of any feature(s) in its available optical spectra. This study forms a part of our ongoing campaign of intranight optical monitoring of radio-quiet WLQs, in order to improve the understanding of this enigmatic class of active galactic nuclei and to look among them for a possible tiny, elusive population of radio-quiet BL Lacs.

Alimentação de Serrasalmus maculatus (Kner, 1858 (Characiformes; Serrasalmidae no trecho inferior bacia do rio Sorocaba, São Paulo, Brasil - DOI: 10.4025/actascibiolsci.v30i3.5011 Feeding of Serrasalmus maculatus (Kner, 1858 (Characiformes; Serrasalmidae in the Sorocaba river, São Paulo State, Brazil - DOI: 10.4025/actascibiolsci.v30i3.5011

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Leandro Muller Gomiero

2008-10-01

Full Text Available O objetivo foi abordar a alimentação de Serrasalmus maculatus. A captura dos exemplares foi realizada com a utilização de redes de emalhar de malhas entre 3 a 8 cm entre nós opostos, totalizando 100 m. Foram coletados 107 indivíduos com comprimento-padrão variando entre 62 e 210 mm, representados principalmente por fêmeas e imaturos. Nenhum indivíduo foi capturado em temperaturas inferiores a 21ºC. Ocorreram quatro categorias de itens alimentares nos estômagos analisados, a saber: pedaços de musculatura de peixe, partes de nadadeiras, fragmentos de vegetais e insetos. Foram feitas comparações entre as classes de comprimento mostrando que ocorrem diferenças significativas nos itens alimentares consumidos na maioria dessas classes. A partir da classe de 165 mm, observaram-se apenas os itens musculatura e vegetais. A disponibilidade dos itens no ambiente e a amplitude de comprimento dos exemplares coletados podem estar mascarando a maior diferenciação ontogenética na dieta desta espécie.The aim of this study was to discuss aspects of the diet of Serrasalmus maculatus. Fish were collected using gill nets, whose lengths measured 100 m and mesh diameters varied from 3 to 8 cm. A total of 107 individuals were collected. Their length varied from 62 to 210 mm. They were mainly represented by female and immature individuals. No individual was caught in temperatures below 21ºC. Four feeding item categories were observed: fish muscle pieces, parts of fish fins, plant fragments, and insects. Comparisons made among individual length classes revealed some significant differences within stomach consumed contents. Individuals whose length exceeded 165 mm consumed only parts of fish muscles and plants. The food availability in the environment and the class lengths amplitude may, however, have influenced the results, in which ontogenetic differences should not be precisely observed.

PRODUKTIVITAS DAN PROFITABILITAS BUDIDAYA IKAN LELE (Clarias gariepinus HASIL SELEKSI DAN NON-SELEKSI PADA PEMELIHARAAN DI KOLAM TANAH

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Raden Roro Sri Pudji Sinarni Dewi

2016-12-01

Full Text Available Ikan lele (Clarias gariepinus merupakan salah satu komoditas budidaya air tawar yang populer di Indonesia. Berbagai upaya dilakukan untuk meningkatkan produktivitas ikan lele di antaranya melalui perbaikan kualitas genetik. Upaya peningkatan kualitas genetik ikan lele untuk mempercepat pertumbuhan dilakukan melalui proses seleksi. Pengujian performa ikan lele hasil seleksi (strain Mutiara pada skala komersial dilakukan dengan membandingkannya dengan strain non-seleksi (strain Paiton. Tujuan dari penelitian ini yaitu untuk membandingkan produktivitas dan profitabilitas budidaya ikan lele hasil seleksi dan non-seleksi yang dibesarkan di kolam tanah pada skala komersial. Ikan lele ukuran sekitar 2,5 g dipelihara di kolam tanah berukuran 50 m2 dengan kepadatan 200 ekor/m2. Pemeliharaan dilakukan sampai ikan mencapai ukuran panen (sekitar 100 g. Hasil penelitian menunjukkan bahwa ikan hasil seleksi memiliki laju pertumbuhan spesifik lebih tinggi (5,75 ± 1,25 g/hari, konversi pakan lebih rendah (0,90 ± 0,08, dan periode pemeliharaan lebih singkat (68 ± 13 hari dibandingkan ikan non-seleksi (4,33 ± 0,70 g/hari; 1,09 ± 0,01; 90 ± 12 hari. Berdasarkan analisis bioekonomi, budidaya pembesaran ikan lele hasil seleksi mampu menekan biaya produksi hingga Rp2.365,00/kg dan mendatangkan rasio keuntungan (61,09 ± 5,17% hampir dua kali lipat lebih tinggi dibandingkan non-seleksi (32,54 ± 4,12%. African catfish (Clarias gariepinus is one of the freshwater aquaculture commodity that are popular in Indonesia. Various attempts had been conducted to increase its productivity including through genetic quality improvement. Efforts to improve the genetic quality of African catfish on growth trait was conducted by selection method. Evaluation the performance of improved strain of African catfish (Mutiara strain on a commercial scale was done by comparing with local (non-improved strain (Paiton strain. The purpose of this study was to compare the productivity and

Somatostatin receptor 2 knockout/lacZ knockin mice show impaired motor coordination and reveal sites of somatostatin action within the striatum.

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Allen, Jeremy P; Hathway, Gareth J; Clarke, Neil J; Jowett, Mike I; Topps, Stephanie; Kendrick, Keith M; Humphrey, Patrick P A; Wilkinson, Lawrence S; Emson, Piers C

2003-05-01

The peptide somatostatin can modulate the functional output of the basal ganglia. The exact sites and mechanisms of this action, however, are poorly understood, and the physiological context in which somatostatin acts is unknown. Somatostatin acts as a neuromodulator via a family of five 7-transmembrane G protein-coupled receptors, SSTR1-5, one of which, SSTR2, is known to be functional in the striatum. We have investigated the role of SSTR2 in basal ganglia function using mice in which Sstr2 has been inactivated and replaced by the lacZ reporter gene. Analysis of Sstr2lacZ expression in the brain by beta-galactosidase histochemistry demonstrated a widespread pattern of expression. By comparison to previously published in situ hybridization and immunohistochemical data, Sstr2lacZ expression was shown to accurately recapitulate that of Sstr2 and thus provided a highly sensitive model to investigate cell-type-specific expression of Sstr2. In the striatum, Sstr2 expression was identified in medium spiny projection neurons restricted to the matrix compartment and in cholinergic interneurons. Sstr2 expression was not detected in any other nuclei of the basal ganglia except for a sparse number of nondopaminergic neurons in the substantia nigra. Microdialysis in the striatum showed Sstr2-null mice were selectively refractory to somatostatin-induced dopamine and glutamate release. In behavioural tests, Sstr2-null mice showed normal levels of locomotor activity and normal coordination in undemanding tasks. However, in beam-walking, a test of fine motor control, Sstr2-null mice were severely impaired. Together these data implicate an important neuromodulatory role for SSTR2 in the striatum.

Mutagenesis of the lac promoter region in M13 mp10 phage DNA by 4'-hydroxymethyl-4,5',8-trimethylpsoralen

International Nuclear Information System (INIS)

Piette, J.; Decuyper-Debergh, D.; Gamper, H.

1985-01-01

Double-stranded M13 phage DNA (M13 mp10 replicative form) was photoreacted with 4'-hydroxymethyl-4,5',8-trimethylpsoralen, using light of wavelength greater than 320 nm or greater than 390 nm to generate predominantly crosslinks or monoadducts, respectively. The damaged DNAs were scored for inactivation and mutagenesis after transfection into Escherichia coli. The appearance of light-blue or colorless plaques on indicator medium showed that mutation had occurred in the lac insert of the viral DNA. A comparison of the consequences of the two phototreatments with psoralen supports the idea that crosslinks are both more lethal and more mutagenic than monoadducts. Numerous mutant clones partially or totally deficient in beta-galactosidase were plaque-purified and amplified. The viral DNA of each clone was sequenced by the dideoxy chain-terminating procedure. All of the observed base-pair changes were mapped to the lac promoter region and consisted of 3 transition, 14 transversion, and 6 single base-pair frame-shift mutations. The predominant mutation was a T.A----G.C transversion

Gene expression analysis in gonads and brain of catfish Clarias batrachus after the exposure of malathion.

Science.gov (United States)

Prathibha, Y; Murugananthkumar, R; Rajakumar, A; Laldinsangi, C; Sudhakumari, C C; Mamta, S K; Dutta-Gupta, A; Senthilkumaran, B

2014-04-01

Pesticides like malathion have the potential to disrupt development and reproduction of aquatic organisms including fishes. To investigate the likely consequences of malathion exposure at low doses in juvenile catfish, Clarias batrachus, we studied the expression pattern of genes encoding certain transcription factors, activin A, sex steroid or orphan nuclear receptors and steroidogenic enzymes which are known to be involved in gonadal development along with histological changes. To compare further, we also analyzed certain brain specific genes related to gonadal axis. Fifty days post hatch catfish fingerlings were exposed continuously to 1 and 10 µg/L of malathion for 21 days. Results from these experiments indicated that transcript levels of various genes were altered by the treatments, which may further affect the gonadal development either directly or indirectly through brain. Histological analysis revealed slow progression of spermatogenesis in testis, while in ovary, the oil droplet oocytes were found to be higher after treatment (10 µg/L). Our findings revealed that the exposure of malathion, even at low doses, hinder or modulate early gonadal development differentially by targeting gene expression pattern of transcription factors, activin A, sex steroid or orphan nuclear receptors and steroidogenic enzymes with an evidence on histological changes. Further, some of the genes showed differential expression at the level of brain in male and female sex after the exposure of malathion. Copyright © 2014. Published by Elsevier Inc.

Long-term exposure to arsenic affects head kidney and impairs humoral immune responses of Clarias batrachus

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Debabrata [Immunobiology Laboratory, School of Life Sciences, Visva-Bharati University, Santiniketan 731235 (India); Datta, Soma [Immunobiology Laboratory, School of Life Sciences, Visva-Bharati University, Santiniketan 731235 (India); Bhattacharya, Shelley [Environmental Toxicology Laboratory, School of Life Sciences, Visva-Bharati University, Santiniketan 731235 (India); Mazumder, Shibnath [Immunobiology Laboratory, School of Life Sciences, Visva-Bharati University, Santiniketan 731235 (India)]. E-mail: shibnath1@yahoo.co.in

2007-02-15

The present study was aimed at determining the effects of long-term arsenic exposure on the head kidney (HK) and ensuing humoral immune responses in Clarias batrachus L. Long-term exposure (150 days) to non-lethal concentrations of arsenic (42.42 {mu}M) resulted in significant time-dependent alterations in HK cell number eventually affecting the HK somatic index. Prolonged exposure to arsenic also suppressed HK-B cell proliferation and led to significant reduction in serum immunoglobulin levels and antigen-specific serum bacterial agglutinin titers. A decline in the number of antigen-specific plaque-forming cells with duration of arsenic exposure was noted in the HK. Enzyme linked immunosorbent assays further revealed that arsenic exposure inhibited the release of 'IL-4 like factors' from HK-T cells. Histological studies documented time-dependent changes in the structure and cellular composition of HK characterized by extensive lymphocytopenia, decrease in melano-macrophage population and hemosiderin accumulation. From exposure-challenge studies with Aeromonas hydrophila it was evident that pathogens could efficiently disseminate and colonize distant host tissues in the exposed fish. Moreover, the ability to decrease the pathogen load was also significantly reduced in the arsenic-exposed fish. Thus long-term exposure to non-lethal concentrations of arsenic affects HK and interferes with the humoral immune system of C. batrachus rendering them immunocompromised and susceptible to pathogenic challenge.

Long-term exposure to arsenic affects head kidney and impairs humoral immune responses of Clarias batrachus

International Nuclear Information System (INIS)

Ghosh, Debabrata; Datta, Soma; Bhattacharya, Shelley; Mazumder, Shibnath

2007-01-01

The present study was aimed at determining the effects of long-term arsenic exposure on the head kidney (HK) and ensuing humoral immune responses in Clarias batrachus L. Long-term exposure (150 days) to non-lethal concentrations of arsenic (42.42 μM) resulted in significant time-dependent alterations in HK cell number eventually affecting the HK somatic index. Prolonged exposure to arsenic also suppressed HK-B cell proliferation and led to significant reduction in serum immunoglobulin levels and antigen-specific serum bacterial agglutinin titers. A decline in the number of antigen-specific plaque-forming cells with duration of arsenic exposure was noted in the HK. Enzyme linked immunosorbent assays further revealed that arsenic exposure inhibited the release of 'IL-4 like factors' from HK-T cells. Histological studies documented time-dependent changes in the structure and cellular composition of HK characterized by extensive lymphocytopenia, decrease in melano-macrophage population and hemosiderin accumulation. From exposure-challenge studies with Aeromonas hydrophila it was evident that pathogens could efficiently disseminate and colonize distant host tissues in the exposed fish. Moreover, the ability to decrease the pathogen load was also significantly reduced in the arsenic-exposed fish. Thus long-term exposure to non-lethal concentrations of arsenic affects HK and interferes with the humoral immune system of C. batrachus rendering them immunocompromised and susceptible to pathogenic challenge

Spectroscopy of 10 γ -Ray BL Lac Objects at High Redshift

Energy Technology Data Exchange (ETDEWEB)

Paiano, Simona; Falomo, Renato [INAF, Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy); Landoni, Marco [INAF, Osservatorio Astronomico di Brera, Via E. Bianchi 46, I-23807 Merate (Italy); Treves, Aldo [Università degli Studi dell’Insubria, Via Valleggio 11, I-22100 Como (Italy); Scarpa, Riccardo [Instituto de Astrofisica de Canarias, C/O Via Lactea, s/n E-38205 La Laguna, Tenerife (Spain)

2017-08-01

We present optical spectra with high signal-to-noise ratio of 10 BL Lac objects detected at GeV energies by the Fermi satellite (3FGL catalog), which previous observations suggested are at relatively high redshift. The new observations, obtained at the 10 m Gran Telescopio Canarias, allowed us to find the redshift for J0814.5+2943 ( z = 0.703), and we can set a spectroscopic lower limit for J0008.0+4713 ( z > 1.659) and J1107.7+0222 ( z > 1.0735) on the basis of Mg ii intervening absorption features. In addition we confirm the redshifts for J0505.5+0416 ( z = 0.423) and J1450+5200 ( z > 2.470). Finally we contradict the previous z estimates for five objects (J0049.7+0237, J0243.5+7119, J0802.0+1005, J1109.4+2411, and J2116.1+3339).

Role of radiation therapy in bladder cancer in the Saguenay-Lac Saint-Jean area

International Nuclear Information System (INIS)

Brochet, F.; Barrette, L.R.

1998-01-01

Bladder cancer is more frequent in Quebec, especially in Saguenay-Lac Saint-Jean than in other Canadian provinces and in the USA. From 1983 to 1996, only 78 patients presenting with bladder cancer received external beam radiation therapy. Sixty-eight were treated with curative intent Overall survival rates were 70% at 3 years, 66% at 5 years, and 40% at 10 years. Retrospective analysis of these cases and literature review show that preoperative radiation therapy is useful in the management of bladder cancer, especially in T3 tumors. It is also useful for patients whose tumor objectively responds to radiation therapy, without an increase in morbidity. (authors)

Evaluation of critical indicators in the process of acquiring supplies and services LAC-UFPE

Science.gov (United States)

Caetano, V. F.; Ferreira, C. V.; dos Santos, M. J.; Honorato, F. A.

2015-01-01

In laboratories linked to public universities and accredited by the NBR ISO/IEC 17025, to meet efficiently item 4.6 (procurement of supplies and services) is a challenge that can be accomplished by programming based on historical purchases and services. In this study, we evaluated the critical procurement items to meet the quality management system of the LAC-UFPE: reagents, certified reference material, of equipment parts, maintenance and calibration of equipment and instruments. It was found that the most critical item is the certified reference material, the purchase or repair of which must be expedited within 125 days prior to the receipt to occur within the desired period.

Analysis of spontaneous deletions and gene amplification in the lac region of Escherichia coli

International Nuclear Information System (INIS)

Albertini, A.M.; Hofer, M.; Calos, M.P.; Tlsty, T.D.; Miller, J.H.

1983-01-01

Spontaneous rearrangements, such as large deletions and duplications, have important implications for the structure of the genome. It is therefore of great interest to analyze these events at the molecular level. We have constructed derivatives of a lacI-Z fusion strain, which allow us to study deletions in a more systematic manner than was previously possible. These derivatives have been used to investigate how frequently larger deletions (> 700 bp) occur between short homologies on both recA and recA - strains and to determine the effect of the lengths of the short homologies and of the distance between homologies on the frequency of deletion formation. 38 references, 11 figures

Geology and age of the Lac a la Perdrix fenite, southern Gatineau district, Quebec

International Nuclear Information System (INIS)

Hogarth, D.D.

1996-01-01

The Lac a Ia Perdrix fenite lies in the Central Metasedimentary Belt of the Grenville Province. This 30 m wide fenite, adjacent to a narrow calciocarbonatite sill, replaces diopside-oligoclase gneiss and is composed of magnesio-arfvedsonite, aegirine, microcline, albite, and fluorapatite. Near the contact with carbonatite, it contains appreciable monazite and barite whereas aegirine virtually disappears. Fenitization probably took place early in the igneous stage of carbonatite development. A Pb/U monazite age of 1026 ± 2 Ma is thought to date fenite formation. Together with published data, this age shows that carbonatite intruded metamorphic rocks near the close of the Grenville Orogeny. (author). 33 refs., 4 tabs., 5 figs

Geology and age of the Lac a la Perdrix fenite, southern Gatineau district, Quebec

Energy Technology Data Exchange (ETDEWEB)

Hogarth, D D [Ottawa Univ., ON (Canada). Dept. of Geology; VanBreemen, O [Geological Survey of Canada, Ottawa, ON (Canada)

1997-12-31

The Lac a Ia Perdrix fenite lies in the Central Metasedimentary Belt of the Grenville Province. This 30 m wide fenite, adjacent to a narrow calciocarbonatite sill, replaces diopside-oligoclase gneiss and is composed of magnesio-arfvedsonite, aegirine, microcline, albite, and fluorapatite. Near the contact with carbonatite, it contains appreciable monazite and barite whereas aegirine virtually disappears. Fenitization probably took place early in the igneous stage of carbonatite development. A Pb/U monazite age of 1026 {+-} 2 Ma is thought to date fenite formation. Together with published data, this age shows that carbonatite intruded metamorphic rocks near the close of the Grenville Orogeny. (author). 33 refs., 4 tabs., 5 figs.

Influence of the salting time on volatile compounds during the manufacture of dry-cured pork shoulder "lacón".

Science.gov (United States)

Purriños, Laura; Franco, Daniel; Carballo, Javier; Lorenzo, José M

2012-12-01

The effect of the length of salting time on volatile compounds throughout the manufacture of dry-cured "lacón" was studied using a purge-and-trap extraction and GC/MS analysis. For this study, six treatments of "lacón" were salted with different amounts of salt (LS (3 days of salting), MS (4 days of salting) and HS (5 days of salting)). The total area of volatile compounds increased significantly (Psalting time increased. Significant differences were found for the total area of all aldehydes for each salting time at the end of process. Hexanal presented the most relative abundance, showing highest content in HS treatments while LS treatments showed the lowest one at the end of salting, post-salting and drying-ripening stage. The influence of salting time on the content of 3-Octen-2-one was significant on salting stage (Psalting time affected (Psalting and at the end of drying-ripening stage. The salting time affected significantly (Psalt level (P>0.05) was detected on total hydrocarbons and total furans at the end of process. Copyright © 2012 Elsevier Ltd. All rights reserved.

Induction of lacI- mutations in Escherichia coli cells after single and split-dose irradiation

International Nuclear Information System (INIS)

Kozubek, S.; Ryznar, L.

1992-01-01

In the lacI system of Escherichia coli, X-ray mutagenesis follows a linear-quadratic curve with suppression; the survival curve is exponential. Dose fractionation leads to nearly complete repair of premutational lesions during an incubation interval of 3.5 h. Repair starts with a delay of 1.5-2 h, suggesting the involvement of an inducible repair/mutation fixation system. The dose-dependence of mutagenesis is described by a simple model assuming two hits being required. A probable explanation might be that the premutagenic lesions consist of two closely spaced lesions on the opposite strands of the DNA molecule. (author)

Structural evidence for induced fit and a mechanism for sugar/H+ symport in LacY

DEFF Research Database (Denmark)

Mirza, Osman Asghar; Guan, Lan; Verner, Gill

2006-01-01

Cation-coupled active transport is an essential cellular process found ubiquitously in all living organisms. Here, we present two novel ligand-free X-ray structures of the lactose permease (LacY) of Escherichia coli determined at acidic and neutral pH, and propose a model for the mechanism...... of coupling between lactose and H+ translocation. No sugar-binding site is observed in the absence of ligand, and deprotonation of the key residue Glu269 is associated with ligand binding. Thus, substrate induces formation of the sugar-binding site, as well as the initial step in H+ transduction....

Cypermethrin and lambda-cyhalothrin induced in vivo alterations in nucleic acids and protein contents in a freshwater catfish, Clarias batrachus (Linnaeus; Family-Clariidae).

Science.gov (United States)

Kumar, Amit; Sharma, Bechan; Pandey, Ravi S

2009-08-01

The fresh water fish, Clarias batrachus, were exposed to sub-acute concentrations of cypermethrin and lambda-cyhalothrin for 96 h to assess their impact on the levels of nucleic acids and protein in different organs of fish. DNA content was found almost unchanged with a single exception of liver, which showed significant increment in the levels of DNA in response to the separate treatments of both compounds. Both RNA and protein contents declined in brain, liver, and muscle while sharp increase was observed in gills. However, in kidney, RNA contents depicted significant enhancement only at higher concentrations, with initial decline at lower concentrations. The trends of alterations in RNA/DNA and protein/DNA ratios were quite similar to the corresponding results explained above for RNA and protein. The results clearly indicated that both of these pyrethroids exerted their effects at transcriptional and translational levels while DNA synthesis was found to be unaffected by these compounds with an exception of liver.

Morphological re-description and new geographical records for three digenean parasites infecting African sharptooth catfish Clarias gariepinus (Pisces: Clariidae) in Egypt.

Science.gov (United States)

Abdel-Gaber, Rewaida; Sakarn, Thabet; El-Shahawi, Gamal; El-Fayoumi, Hoda; Mohammed, Rana

2016-11-01

Sixty specimens of African sharptooth catfish Clarias gariepinus (Clariidae) were collected during the period of March 2014-February 2015 from boat landing sites and fishermen of the River Nile at Beni Suef Governorate, Egypt, and examined for the presence of digenean parasites. The morphology of these parasites was studied by using light microscopy to describe morphological and morphometrically measurements for different body parts. Three digenean species belonging to three different genera were collected from various organs within the examined fish species. A certain degree of site specificity was also observed, with Thaparotrema botswanensis being found only in the gall bladder of C. gariepinus, while both Pseudoholorchis clarii and Glossidium pedatum were found only in the intestine and thus seem to occupy a certain niche within their host. This study represent as the first record of T. botswanensis and G. pedatum from C. gariepinus, as well as the first report of the genera from the River Nile in Egypt. In addition, re-description of P. clarii clarifies measurements for some body parts.

ANTI-CORRELATED OPTICAL FLUX AND POLARIZATION VARIABILITY IN BL LAC

Energy Technology Data Exchange (ETDEWEB)

Gaur, Haritma [Inter-University Centre for Astronomy and Astrophysics (IUCAA), Ganeshkhind, Pune 411 007 (India); Gupta, Alok C. [Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital 263 129 (India); Wiita, Paul J. [Department of Physics, The College of New Jersey, P.O. Box 7718, Ewing, NJ 08628-0718 (United States); Uemura, Makoto; Itoh, Ryosuke; Sasada, Mahito, E-mail: haritma@iucaa.ernet.in [Hiroshima Astrophysical Science Center, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan)

2014-01-20

We present the results of photometric (V band) and polarimetric observations of the blazar BL Lac during 2008-2010 using TRISPEC attached to the KANATA 1.5 m telescope in Japan. The data reveal a great deal of variability ranging from days to months with detection of strong variations in fractional polarization. The V band flux strongly anticorrelates with the degree of polarization during the first of two observing seasons but not during the second. The direction of the electric vector, however, remained roughly constant during all of our observations. These results are consistent with a model with at least two emission regions being present, with the more variable component having a polarization direction nearly perpendicular to that of the relatively quiescent region so that a rising flux can produce a decline in degree of polarization. We also computed models involving helical jet structures and single transverse shocks in jets and show that they might also be able to agree with the anticorrelations between flux and fractional polarization.

A screen for bacterial endosymbionts in the model organisms Tribolium castaneum, T. confusum, Callosobruchus maculatus, and related species.

Science.gov (United States)

Goodacre, Sara L; Fricke, Claudia; Martin, Oliver Y

2015-04-01

Reproductive parasites such as Wolbachia are extremely widespread amongst the arthropods and can have a large influence over the reproduction and fitness of their hosts. Undetected infections could thus confound the results of a wide range of studies that focus on aspects of host behavior, reproduction, fitness, and degrees of reproductive isolation. This potential problem has already been underlined by work investigating the incidence of Wolbachia infections in stocks of the model system Drosophila melanogaster. Here we survey a range of lab stocks of further commonly used model arthropods, focusing especially on the flour beetles Tribolium castaneum and Tribolium confusum, the cowpea weevil Callosobruchus maculatus and related species (Coleoptera: Tenebrionidae and Bruchidae). These species are widespread stored product pests so knowledge of infections with symbionts further has potential use in informing biocontrol measures. Beetles were assessed for infection with 3 known microbial reproductive parasites: Wolbachia, Rickettsia, Spiroplasma. Infections with some of these microbes were found in some of the lab stocks studied, although overall infections were relatively rare. The consequences of finding infections in these or other species and the type of previous studies likely to be affected most are discussed. © 2013 Institute of Zoology, Chinese Academy of Sciences.

Lower than expected mercury concentration in piscivorous African sharptooth catfish Clarias gariepinus (Burchell)

International Nuclear Information System (INIS)

Desta, Zerihun; Borgstrom, Reidar; Rosseland, Bjorn Olav; Dadebo, Elias

2007-01-01

The concentrations of total mercury (THg), stable isotopes of nitrogen (δ 15 N) and carbon (δ 13 C), and the diet of the African sharptooth catfish Clarias gariepinus in Lake Awassa, Ethiopia, were studied from January 2003 to February 2004. Values of the δ 15 N were used as an index of trophic position in four length groups and compared to actual stomach contents. The diet of C. gariepinus within the length range of 201-600 mm L T mainly consisted of the small barb Barbus paludinosus, aquatic insects, and mollusks. The proportion of fish prey in the diet was 60% by volume, irrespective of fish size. The differences in δ 15 N values of individuals within and between length classes were less than 3 per mille , and were not significantly related to total length, showing the similarity in trophic niche of the different sizes, which corresponded to recorded stomach contents. Mercury concentrations were in the range of 0.002-0.154 mg kg -1 ww, and had no significant relationship to total length. Hence, even large specimens of C. gariepinus have Hg values below the WHO threshold of 0.2 mg kg -1 ww. The slope of the regression line between log [Hg] and δ 15 N was small, 0.06, indicating the absence of trophic shifts and biomagnification of Hg in larger specimens in our samples. The low Hg concentrations in C. gariepinus compared to the Hg concentrations in other piscivorous fish species in Lake Awassa, such as Barbus intermedius and B. paludinosus, may be due to its dependence on invertebrate preys at small size, diet switching towards low Hg prey fish at larger size, and growth biodilution owing to higher growth rate

MICROSATELLITE GENETIC VARIATION IN CULTURED POPULATIONS OF AFRICAN CATFISH (Clarias gariepinus IN INDONESIA

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Imron Imron

2011-06-01

Full Text Available African catfish, Clarias gariepinus, is one of economically important farmed species in Indonesia. To support the development of aquaculture industry, high genetic quality of both broodstock and seeds is required and breeding program is considered as viable option. Information on genetic variation of the populations being considered to form a base population may give insight toward the appropriate strategy to be implemented in breeding program. This study was aimed to assess genetic variation in farmed populations of catfish in Indonesia using microsatellite markers with special emphasis on their use to develop breeding program. Three populations of farmed catfish, namely Dumbo, Paiton, and Sangkuriang were collected. Fifteen individuals representing each population were screened for microsatellite variability using seven primer sets (cga01, cga02, cga03, cga05, cga06, cga09, cga10. Results found that with exception of two loci (cga01 and cg02 which had a slight increase, the other four loci showed reduction in the number of alleles ranging from 35% to 80% depending on loci. Farmed populations also showed heterozygote deficient and inbreeding level, being the highest was found in Sangkuriang and the least was observed in Dumbo population. Individuals within populations contributed most (95% while interpopulation variation accounted for only 5% of the total genetic variation. Populations of Dumbo and Sangkuriang were genetically similar while populations of Paiton were genetically different from both Dumbo and Sangkuriang. Viewed from genetic perspective, by combining all information emerging from this study, the best possible strategy to establish a base population with broad genetic base and less inbreeding would be to combine all the populations into a synthetic base population.

A 400-year phytolith-based reconstruction of wild rice (Zizania palustris) abundance from Mud Lake core sediments, Fond du Lac Band of Lake Superior Chippewa Reservation, Minnesota, USA.

Science.gov (United States)

Munoz, R.; Caylor, E.; Yost, C. L.; Drake, C.; Ladwig, J. L.; Myrbo, A.; Howes, T.

2014-12-01

Wild rice (Zizania palustris L.) is an aquatic grass with spiritual and subsistence significance to Native people of the Great Lakes region of North America. Mud Lake (Mashkiigwaagamaag), located on the Fond du Lac Band of Lake Superior Chippewa Reservation in Carlton County, Minnesota, USA, once supported an extensive population of wild rice (manoomin). However, early 20th century attempts to ditch and drain surrounding wetlands for landuse intensification severely altered the natural hydrological system that supports wild rice. Fond du Lac Resource Management (FDLRM) technicians are currently working to increase the wild rice population in Mud Lake. As part of these efforts, this phytolith study was undertaken to better understand how wild rice abundance has fluctuated over the past 400 years, with particular emphasis on the 19th and 20th centuries. Phytoliths are microscopic opal silica plant remains that are incorporated into soils and lake sediments after the plant-parts that contain them decay. Wild rice produces phytolith morphotypes that are unequivocally diagnostic. Mud Lake core MNMN-MUD11-1C-1P-1 (46°43'38.39"N, 92°42'2.45"W) was piston cored by LacCore (National Lacustrine Core Facility) and FDLRM technicians on 24 May 2011. Initial core descriptions, multi-sensor core logging, phytolith sampling and phytolith extractions were completed during the summer of 2014 at LacCore. Wild rice phytolith identification and quantification was conducted on twelve samples using brightfield microscopy at 400x magnification. Wild rice phytolith concentration values ranged from 68 to 2,300 phytoliths/cm3. Wild rice accumulation rates ranged from 9 to 383 phytoliths/ cm2/yr, peaking in 1952 AD. Wild rice abundance in Mud Lake appears to be influenced by a complex set of variables that include anthropogenic disturbance, climatic events and aquatic plant community succession.

Additional new species of Hypostomus Lacépède, 1803, from Surinam; with remarks on the apparent „gymnorhynchus-complex” (Siluriformes, Loricariidae)

NARCIS (Netherlands)

Boeseman, M.

1969-01-01

Two new Surinam species of Hypostomus Lacépède are described, and their relationship is discussed; a group of three forms from eastern Surinam and (French) Guyane (gymnorhynchus-complex) is reconsidered; the species H. plecostomus (Linnaeus) is reported to hitherto survive in the lacustrine

Neuropeptide Y in the olfactory system, forebrain and pituitary of the teleost, Clarias batrachus.

Science.gov (United States)

Gaikwad, Archana; Biju, K C; Saha, Subhash G; Subhedar, Nishikant

2004-03-01

Distribution of neuropeptide Y (NPY)-like immunoreactivity in the forebrain of catfish Clarias batrachus was examined with immunocytochemistry. Conspicuous immunoreactivity was seen in the olfactory receptor neurons (ORNs), their projections in the olfactory nerve, fascicles of the olfactory nerve layer in the periphery of bulb and in the medial olfactory tracts as they extend to the telencephalic lobes. Ablation of the olfactory organ resulted in loss of immunoreactivity in the olfactory nerve layer of the bulb and also in the fascicles of the medial olfactory tracts. This evidence suggests that NPY may serve as a neurotransmitter in the ORNs and convey chemosensory information to the olfactory bulb, and also to the telencephalon over the extrabulbar projections. In addition, network of beaded immunoreactive fibers was noticed throughout the olfactory bulb, which did not respond to ablation experiment. These fibers may represent centrifugal innervation of the bulb. Strong immunoreactivity was encountered in some ganglion cells of nervus terminalis. Immunoreactive fibers and terminal fields were widely distributed in the telencephalon. Several neurons of nucleus entopeduncularis were moderately immunoreactive; and a small population of neurons in nucleus preopticus periventricularis was also labeled. Immunoreactive terminal fields were particularly conspicuous in the preoptic, the tuberal areas, and the periventricular zone around the third ventricle and inferior lobes. NPY immunoreactive cells and fibers were detected in all the lobes of the pituitary gland. Present results describing the localization of NPY in the forebrain of C. batrachus are in concurrence with the pattern of the immunoreactivity encountered in other teleosts. However, NPY in olfactory system of C. batrachus is a novel feature that suggests a role for the peptide in processing of chemosensory information.

Ionoregulatory Impairment in African Catfish (Clarias gariepinus Exposed to Combined Stressors of Lead and Cypermethrin

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Omowumi O ADEWALE

2014-03-01

Full Text Available The contamination of aquatic ecosystem with heavy metals and pesticides has increased dramatically over the years, and this has generated a lot of attention by environmental experts. There are reports on impacts of different single toxicants on aquatic organisms but not much has been done to investigate the impacts of mixtures of toxicants on aquatic life. In this study we investigated the effects of multiple stressors of Pb and cypermethrin on ionoregulation in the African catfish (Clarias gariepinus. Adults C. gariepinus were exposed to either borehole water (control, 2 mg/L Pb, 0.5 μg/L cypermetrin or a mixture of 2 mg/L Pb and 0.5 μg/L cypermethrin for 96 h, after which the levels of plasma Na+, Cl- and K+ were determined as a measure of branchial ionoregulatory disturbance. The exposure of C. gariepinus to 0.5 μg/L cypermethrin resulted in a significant reduction in plasma Na+ (43% decrease and Cl- (31% decrease but a 2-fold increase in plasma K+ concentrations. Exposure to a mixture of cypermethrin and Pb resulted in 53% decrease in plasma Na+, 40% decrease in plasma Cl- and a 3- fold increase in plasma K+. There was no significant difference between the control and those exposed to just only 2 mg/L Pb for all the parameters measured. The results of this study indicated that exposure of aquatic organisms to combined stressors of heavy metals pollution as well as pesticide contamination could have a serious effect on the physiology especially on ionic regulation in the exposed fish.

Nutritional value of raw Canavalia ensiformis and its utilization as partial replacement for soybean meal in the diet of Clarias gariepinus (Burchell, 1822) fingerlings.

Science.gov (United States)

Solomon, Shola G; Okomoda, Victor T; Oguche, Obekpa

2018-01-01

The nutritional value of raw Jack bean meal ( Canavalia ensiformis ) as a partial substitute for soybeans meal was investigated in this study. Preliminary investigation on nutrient composition revealed that lysine, histidine, and phenylalanine were significantly higher in C .  ensiformis seed meal compared to soybean meal. However, crude protein and other essential amino acids were significantly lower. Feeding trial was then conducted to investigate the effect of replacing about 40% soybeans meal (at 58.8% inclusion) with C .  ensiformis in the diet of Clarias gariepinus . The result obtained after 56 days revealed that fingerlings could tolerate up to 20% replacement without significant effect on growth and nutrient utilization. Beyond this, growth was significantly reduced. Survivals of the fish also follow a similar trend as stated above. It was concluded that dietary inclusion of raw C .  ensiform meal should not be beyond 11% (or 20% replacement for soybeans meal included at 58.8%) in the diet of C .  gariepinus .

Optimization of lignin peroxidase, manganese peroxidase, and Lac production from Ganoderma lucidum under solid state fermentation of pineapple leaf

OpenAIRE

Sudha Hariharan; Padma Nambisan

2013-01-01

This study was undertaken to isolate ligninase-producing white-rot fungi for use in the extraction of fibre from pineapple leaf agriwaste. Fifteen fungal strains were isolated from dead tree trunks and leaf litter. Ligninolytic enzymes (lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (Lac)), were produced by solid-state fermentation (SSF) using pineapple leaves as the substrate. Of the isolated strains, the one showing maximum production of ligninolytic enzymes was identified...

Observations préliminaires sur la répartition et les fluctuations de l'ichtyomasse exploitable dans les différentes zones écologiques du lac Ihema (bassin moyen de l'Akagera, Rwanda

Directory of Open Access Journals (Sweden)

Mughanda, M.

1988-01-01

Full Text Available Preliminary considerations on distribution and changes in fishable ichtyomass in the ecological areas of lake Ihema (Akagera middle, Foodplain, Rwanda. Since 1981, commercial fishing is accomplished in lake Ihema with gillnets of 50 mm meshes and a mean of 175 tons of fish was caught per year during the first three years. Simultaneously, experimental fishing was introduced since 1982, for which ten gillnets of different meshes are used. Fishes of the two general Tilapia and Clarias are captured in commercial fishing, but in experimental one, about ten taxons of fish are caught. For this paper, we examined statistics obtained from experimental catches during 1982 and 1983. Apart from Tilapia and Clarias, small Cichlidae of Haplochromis group, two species of Mormyridae and Synodontis spp represent a potential which may be exploited with other kinds of gear. Concerning productiveness of fishing areas in lake Ihema, littoral zones (= inshore are more rich than pelagic (= offshore ones and the northern sector in which Akagera river enters the lake is the most productive. Species of fish are differently represented in ecological zones, following the kind of their food (planctonophagous, detritivorous or carnivorous and the places they can reproduce. Catches fluctuate monthly and annually probably because of natural changes in fish stock according to fluctuations of climatic conditions, but also because of increasing intensity of commercial fishing. For Tilapia, reduction in the quantity captured may also be due to introgressive hybridization and competition between T. macrochir, T. nilotica and their hybrids.

Study of sodium arsenite induced biochemical changes on certain biomolecules of the freshwater catfish Clarias batrachus

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Randhir Kumar

2012-01-01

Full Text Available Toxic impact of sublethal concentration (1 mg/L; 5% of 96h LC50 value of sodium arsenite (NaAsO2 on certain biomolecules (proteins, nucleic acids, lipids, and glycogen of five tissue components (muscles, liver, brain, skin, and gills of the freshwater catfish Clarias batrachus was analysed. The important toxic manifestations include marked decrease in the concentration of proteins (21.72-45.42% in muscles; 3.42-53.94% in liver; 15.39-45.42% in brain; 15.40-4.00% in skin and 11.35-64.13% in gills, DNA (0.55-22.95% in muscles; 8.33-14.06% in liver; 5.30-18.40% in brain; 13.57-52.80% in skin; and 12.38-31.01% in gills, RNA (42.68-76.16% in muscles; 10.68-39.75% in liver; 5.66-29.05% in brain; 7.72-27.93% in skin and 21.47-44.38% in gills and glycogen (24.00-51.72% in muscles; 49.11-72.45% in liver; 11.49-26.03% in brain; 26.13-38.05% in skin and 17.80-37.97% in gills. Excepting liver where the lipid content increases (15.82-24.13%, the fat content also showed depletion in their concentration (10.40-29.83% in muscles; 8.30-34.45% in brain; 8.94-31.47% in skin and 12.75-28.86% in gills, in the rest of the organ systems.Foi analisado o impacto tóxico da concentração subletal (1 mg/L; 5% do valor de LC50 de 96h do arsenito de sódio (NaAsO2 sobre certas biomoléculas (proteinas, ácidos nucleicos, lipídios e glicogênio de cinco tecidos (músculos, fígado, cérebro, pele e brânquias do bagre Clarias batrachus. As manifestações tóxicas importantes incluiram o decréscimo acentuado na concentração de proteinas (21,72-45,42% nos músculos; 3,42-53,94% no fígado; 15,39-45,42% no cérebro; 15,40-4,00% na pele e 11,35-64,13% nas brânquias, DNA (0,55-22,95% nos músculos; 8,33-14,06% no fígado; 5,30-18,40% no cérebro; 13,57-52,80% na pele e 12,38-31,01% nas brânquias, RNA (42,68-76,16% nos músculos; 10,68-39,75% no fígado; 5,66-29,05% no cérebro; 7,72-27,93% na pele e 21,47-44,38% nas brânquias e glicogênio (24,00-51,72% nos músculos; 49

Efecto de la salinidad en la supervivencia embrionaria de puye Galaxias maculatus (Jenyns, 1842

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Juan Barile

2015-05-01

Full Text Available Se evaluó e l efecto de la salinidad en la supervivencia embrionaria, período embrionario y período de eclosión de puye, Galaxias maculatus. Se utilizaron ocho tratamientos, con salinidades de 0, 4, 8, 12, 16 y 20 obteniéndose supervivencias embrionarias promedios respectivas de 84,9; 84,0; 85,5; 86,1; 82,6 y 75,8%, sin diferencias significativas entre ellas, mientras que con salinidad de 24 se obtuvo sobrevivencia de 10,4%, significativamente diferente al resto de los tratamientos y con salinidad de 28 causó 100% de mortalidad. A diferencia del estado juvenil y adulto, el embrión es incapaz de resistir la salinidad marina y su umbral de tolerancia se encuentra entre salinidades de 24 y 28. Las mayores supervivencias promedios larvales a 10 días de vida fueron con salinidades intermedias de 8, 12 y 16 de 79,3; 80,3 y 74,6% respectivamente, sin diferencias significativas entre ellas, demostrando alta viabilidad del embrión post-eclosión. Los períodos embrionarios promedios (50% más breves fueron a bajas salinidades 0, 4, 8, 12 con 28,7; 28,0; 29,7 y 29,7 días y los más extensos en los tratamientos con salinidades de 16 y 20, con 34,0 y 34,3 días, sin diferencias significativas entre ellos. Los períodos de eclosión promedio (50% con salinidades de 0, 4, 8, 12, 16, 20 y 24 fueron de 5,0; 5,5; 7,5; 8,8; 13,0; 14,3 y 15,8 días respectivamente, sin diferencias significativas entre ellos.

Isolation and characterization of Tn917lac-generated competence mutants of Bacillus subtilis

International Nuclear Information System (INIS)

Hahn, J.; Albano, M.; Dubnau, D.

1987-01-01

The authors isolated 28 mutants of Bacillus subtilis deficient in the development of competence by using the transposon Tn917lacZ as a mutagen. The mutant strains were poorly transformable with plasmid and chromosomal DNAs but were normally transducible and exhibited wild-type resistance to DNA-damaging agents. The mutations were genetically mapped, and the mutants were characterized with respect to their abilities to bind and take up radiolabeled DNA. All were defective in uptake, and some failed to bind significantly amounts of DNA. The abilities of the mutant strains to resolve into two buoyant density classes on Renografin gradients were studied. Most resolved normally, but several banded in Renografin only at the buoyant density of noncompetent cells. The genetic mapping studies and the other analyses suggested that the mutations define a minimum of seven distinct com genes

Genetic variability and resistance of cultivars of cowpea [Vigna unguiculata (L.) Walp] to cowpea weevil (Callosobruchus maculatus Fabr.).

Science.gov (United States)

Vila Nova, M X; Leite, N G A; Houllou, L M; Medeiros, L V; Lira Neto, A C; Hsie, B S; Borges-Paluch, L R; Santos, B S; Araujo, C S F; Rocha, A A; Costa, A F

2014-03-31

The cowpea weevil (Callosobruchus maculatus Fabr.) is the most destructive pest of the cowpea bean; it reduces seed quality. To control this pest, resistance testing combined with genetic analysis using molecular markers has been widely applied in research. Among the markers that show reliable results, the inter-simple sequence repeats (ISSRs) (microsatellites) are noteworthy. This study was performed to evaluate the resistance of 27 cultivars of cowpea bean to cowpea weevil. We tested the resistance related to the genetic variability of these cultivars using ISSR markers. To analyze the resistance of cultivars to weevil, a completely randomized test design with 4 replicates and 27 treatments was adopted. Five pairs of the insect were placed in 30 grains per replicate. Analysis of variance showed that the number of eggs and emerged insects were significantly different in the treatments, and the means were compared by statistical tests. The analysis of the large genetic variability in all cultivars resulted in the formation of different groups. The test of resistance showed that the cultivar Inhuma was the most sensitive to both number of eggs and number of emerged adults, while the TE96-290-12-G and MNC99-537-F4 (BRS Tumucumaque) cultivars were the least sensitive to the number of eggs and the number of emerged insects, respectively.

Determination of quarantine period in African catfish (Clarias gariepinus) fed with pig (Sus sp.) offal to assure compliance with halal standards.

Science.gov (United States)

Wan Norhana, M N; Dykes, G A; Padilah, B; Ahmad Hazizi, A A; Masazurah, A R

2012-12-01

Pig (Sus sp.) and pig by-products are considered as najasa (impurities) in Islam and forbidden in Muslim consumer products. Animals fed on najasa are categorised as al-jallālah (contaminated animals) which are allowed to be consumed as long as they have been quarantined for a certain period of time. During this quarantine period the animals will have undergone a natural purification process or istihālah. African catfish (Clarias gariepinus) are commonly consumed in Malaysia and may be fed on najasa. This study was carried out to estimate the istihālah period for catfish after feeding with pig offal, based on the absence of pig DNA in catfish gut and to suggest the quarantine period in catfish fed with pig offal. The results indicated that the maximum istihālah period could reach 36h in the stomach, 6h in the midgut and less than 2h in the hindgut although in many cases shorter periods were observed. Based on these results it is estimated that the minimum quarantine period for catfish fed with pig offal is 1.5days. Copyright © 2012 Elsevier Ltd. All rights reserved.

RECOVERY OF DAMAGES IN THE SKIN OF ARSENIC EXPOSED CLARIAS BATRACHUS (LINN. FOLLOWING WITHDRAWAL OF THE STRESS

Directory of Open Access Journals (Sweden)

A. K. Singh ، T. K. Banerjee

2008-10-01

Full Text Available The bottom dwelling air-breathing catfish, Clarias batrachus (Linn. also respires via its skin (an accessory water-breathing organ. Prolonged (90 days exposure to disodium arsenate heptahydrate has caused massive damage (e.g. wear and tear of various cellular components including club cells, hypertrophy and hyperplasia of the goblet mucous cells, altered staining and the slimy secretion to the epidermis of its skin. The present study investigated the recovery in architecture of the damaged epidermis following return of the 90 days disodium arsenate heptahydrate exposed fish to clean water. The significant regeneration of its different cellular components (epithelial cells, Club cells, Mucous cells took place after 24 h of withdrawal when sloughing; wear and tear and other damages of the epidermis of the skin got substantially reduced. The histopathological alterations which still continued included squeezing out of contents of the Club cells that formed a thin layer on the body surface. Regeneration of the Club cells continued throughout the epidermis even though the newly formed Club cells still showed massive sign of degeneration. Altered staining behaviour and hyperactivity of the Mucous cells continues even after prolonged withdrawal of the stress of the arsenic salt. Similarly the glycoproteins of the slime secreted by the mucous cells retained their sulphate moieties. This indicates that disodium arsenate heptahydrate induces certain permanent non-reversible damages including altered mucogenic activity in the epidermis of the skin of C. batrachus.

New Light Curves and Analysis of the Overcontact Binaries PP Lac and DK Sge

Science.gov (United States)

Sanders, S. J.; Hargis, J. R.; Bradstreet, D. H.

2004-12-01

As a by-product of the ongoing work with the Catalog and AtLas of Eclipsing Binaries database (CALEB; Bradstreet et al. 2004), several hundred eclipsing binary systems have been identified that have either unpublished or poor quality light curves. We present new V & Rc light curves for the overcontact systems PP Lac and DK Sge, both chosen because their deep eclipses (peak-to-peak amplitudes of nearly 0.7 mag) help constrain the light curve modelling. Data were obtained using the 41-cm telescope at the Eastern University Observatory equipped with an SBIG ST-10XME CCD. PP Lac (P= 0.40116 d) is a W-type contact binary with only one previously published light curve (Dumont & Maraziti 1990), but the data are sparse and almost non-existent at primary eclipse. Modelling of these data gave varying results; the published mass ratios differ by nearly 0.3. Our data confirms the noted differing eclipse depths but we find the primary eclipse to be total. We present a new light curve solution using Binary Maker 3 (Bradstreet & Steelman 2002) and Wilson-Devinney, finding the mass ratio to be well-constrained by the duration of total eclipse. A period study will be presented using previously existing and newly derived times of minimum light. DK Sge (P=0.62182 d) appears to be an A-type contact binary with no published light curve. The eclipses are partial, with the primary eclipse being deeper by about 0.08 mag. The maxima show evidence of a slight asymmetry, although the light curve appears to be repeatable over the 1 month of observations. We present the first light curve solution using Binary Maker 3 and Wilson-Devinney, but have limited mass ratio constraints due to the absence of radial velocity data. A period study will be presented using previously existing and newly derived times of minimum light.

First Nustar Observations of the Bl Lac-Type Blazar Pks 2155-304: Constraints on the Jet Content and Distribution of Radiating Particles

DEFF Research Database (Denmark)

Madejski, G. M.; Nalewajko, K.; Madsen, K. K.

2016-01-01

We report the first hard X-ray observations with NuSTAR of the BL Lac-type blazar PKS 2155-304, augmented with soft X-ray data from XMM-Newton and γ-ray data from the Fermi Large Area Telescope, obtained in 2013 April when the source was in a very low flux state. A joint NuSTAR and XMM spectrum, ...

Typha control efficiency of a weed-cutting boat in the Lac de Guiers in Senegal : A preliminary study on mowing speed and re-growth capacity

NARCIS (Netherlands)

Hellsten, S.; Dieme, C.; Mbengue, M.; Janauer, G.A.; Hollander, den N.G.; Pieterse, A.H.

1999-01-01

Prolific growth of Typha australis in the lower part of the Senegal River and the Lac de Guiers resulted from changed ecological conditions following the construction of two high dams in the Senegal River. Fluctuation of the water level has decreased markedly and the water has changed from brackish

Manganese, nickel and strontium bioaccumulation in the tissues of the African sharptooth catfish, Clarias gariepinus from the Olifants River, Kruger National Park

Directory of Open Access Journals (Sweden)

Annemarie Avenant-Oldewage

2000-07-01

Full Text Available The gills, liver, muscle and skin were collected from Clarias gariepinus, during four surveys (February, May, June and November in 1994 from two sites on the Olifants River in the Kruger National Park. With the use of atomic absorption spectrophotometry, metal concentrations of manganese, nickel and strontium bioaccumulated in these tissues were determined. This information was then used to differentiate between the concentrations found at the two locations and between the four survey periods. The con- centration of the metals were found to be highest in the gills, followed by the liver. This suggests the gills to be the primary uptake tissue for these metals following their intimate blood-water contact. The concentration of manganese and strontium, with particular reference to the gills, showed highest bioaccumulation at Mamba. Very little differences in the nickel concentrations were found at both Mamba and Balule. Water bioconcentration factors for manganese and nickel were much higher than that noted for sediment, suggesting a much lower bioavailability of these metals from the sediment. On the other hand, sediment bioconcentration factors for strontium were generally higher than that for water, which could imply higher bioavailability and concentration from the sediment.

Helmintos parasitos das espécies Scomberomorus cavalla (Cuvier e Scomberomorus maculatus (Mitchill do litoral cearense: Contracaecum fortalezae sp. n. (Nematoda, Ascaridoidea

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Vera Lucia M. Klein

1973-01-01

Full Text Available De nematódeos encontrados parasitando estômago, intestinos delgado e grosso de Scomberomorus cavalla (Cuv. e Scomberomorus maculatus (Mitch. o autor propões para o gênero Contracaecum Railliet et Henry, 1912 uma nova espécie, C. fortalezae sp. n., que mais se aproxima de C. clavatum (Rud., 1809 Baylis, 1920 dela se diferenciando por possuir espículos desiguais, um curto ovejetor, útero opistodelfo, ovos menores e por apresentar em todos exemplares estudados ceco intestinal curto e ceco esofagiano longo.In this paper the author proposes a new species of the genus Contracaecum Railliet et Henry, 1912. Of the species under Contracaecum, Contracaecum clavatum (Rudolphi, 1809 Baylis, 1920 is the nearest to Contracaecum fortalezae sp. n. differing from the latter by the following aspects: The males have unequal spicules. The females have a short ovijector and parallel uteri directed backward and the eggs are smaller. In both sexes the intestinal cecum is always short and the ventricular posterior appendix is always long, while Contracaecum clavatum presents these structures in an inverse way, considering the lenght of them. Besides, the thorn-like formations at the posterior end of the body are different.

Effect of photoperiod on some biological parameters of Clarias gariepinus juvenile

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Solomon S. G.

2012-11-01

Full Text Available Photoperiod effect on Growth parameters and cannibalism of Clarias gariepinushave been well documented in resent past, but little is known about the response of other biological parameters such as, Condition factor, Shooters composition, Body colouration and Blood glucose of this important tropical fish species to different photoperiods, therefore the present study was designed to evaluate these responses of the African catfish to 24 hours of light (00D:24L, 24 hours of darkness (24D: 00L and 12 hour light / 12 hours darkness (12D: 12L. The six weeks experiment observed significant differences (P0.05 at the end of the experiment and were Significantly lower than value obtained at the start of the experiment, Shooters composition was highest in 00D:24L (41.5% i.e. 27 of 65 leading to high mortality (13.33% due to cannibalism compared to 12D: 12L (Shooters =15.27% i.e. 11 of 72, Mortality= 4% and 24D: 00L (Shooters=5.33% i.e. 4 of 75, Mortality= 0% photoperiod. More so, 93.33% (70 of 75 of fish in the dark phase (24D: 00Lexhibited Deep shiny black body colouration, while 6.67% (5 of 75 was observed of Normal fish colouration. However the fishes in the 00D: 24L photoperiod were observed to be predominantly Lighter skin colouration, (80% i.e. 52 of 65= lighter colouration, 18.46% i.e. 12 of 65= Normal skin coloration and 1.53 i.e. 1 of 65= Deep black body colouration while 12D: 12L were of Normal skin colouration (100% Normal skin colouration, also blood glucose was observed to increase as the light hours increased (P<0.05 with 24D: 00L photoperiod having the highest blood glucose level of 5.7+0.5, while those in 12D: 12L had 4.4+0.3 and 24D: 00L had the least value of 3.9+0.1. This study therefore establishes the fact that photoperiod may have no effect on the condition factor of African catfish, while higher shooters composition is highlighted as one of the causes of increased mortality and could be reduced to a large extent with reduced light

Burn care in Los Angeles, California: LAC+USC experience 1994-2004.

Science.gov (United States)

Garner, Warren L; Reiss, Matthew

2005-01-01

The LAC+USC Burn Center has admitted 3118 patients for treatment in the last 10 years. A majority of patients were young adults (1868), with the second largest group being small children (543). The ethnicity of the patients reflects the diverse nature of the population of Los Angeles County. Forty-eight percent of injuries were less than 5% TBSA and approximately 2% were greater than 60% TBSA. Eighty-two percent were accidental injuries. Sixty percent of admitted patients underwent skin grafting. Mortality was negligible in the group with burns over less than 10% of their body and very high (15/19), 79% in the most severely burned group. Further, there was a high correlation between age and mortality. Complications during treatment included: deep venous thrombosis 1% per year; pulmonary emboli in 5 patients; endotracheal tube dislodgment early or self-extubation about 1 month (11.3 per year); 4.5 patients per year who developed acute renal failure; abdominal compartment syndrome developed in 4.7 patients each year; heterotopic ossification was seen in 4 patients (0.4%); 4 patients (0.4%) developed stage II-IV pressure sores; hypothermia was present in 0.8% of patients.

Gene fusions with lacZ by duplication insertion in the radioresistant bacterium Deinococcus radiodurans

International Nuclear Information System (INIS)

Lennon, E.; Minton, K.W.

1990-01-01

Deinococcus radiodurans is the most-studied species of a eubacterial family characterized by extreme resistance to DNA damage. We have focused on developing molecular biological techniques to investigate the genetics of this organism. We report construction of lacZ gene fusions by a method involving both in vitro splicing and the natural transformation of D. radiodurans. Numerous fusion strains were identified by expression of beta-galactosidase. Among these fusion strains, several were inducible by exposure to the DNA-damaging agent mitomycin C, and four of the inducible fusion constructs were cloned in Escherichia coli. Hybridization studies indicate that one of the damage-inducible genes contains a sequence reiterated throughout the D. radiodurans chromosome. Survival measurements show that two of the fusion strains have increased sensitivity to mitomycin C, suggesting that the fusions within these strains inactivate repair functions

DNA barcoding of Clarias gariepinus, Coptodon zillii and Sarotherodon melanotheron from Southwestern Nigeria [version 1; referees: 2 approved

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Mofolusho O. Falade

2016-06-01

Full Text Available DNA barcoding has been adopted as a gold standard rapid, precise and unifying identification system for animal species and provides a database of genetic sequences that can be used as a tool for universal species identification. In this study, we employed mitochondrial genes 16S rRNA (16S and cytochrome oxidase subunit I (COI for the identification of some Nigerian freshwater catfish and Tilapia species. Approximately 655 bp were amplified from the 5′ region of the mitochondrial cytochrome C oxidase subunit I (COI gene whereas 570 bp were amplified for the 16S rRNA gene. Nucleotide divergences among sequences were estimated based on Kimura 2-parameter distances and the genetic relationships were assessed by constructing phylogenetic trees using the neighbour-joining (NJ and maximum likelihood (ML methods. Analyses of consensus barcode sequences for each species, and alignment of individual sequences from within a given species revealed highly consistent barcodes (99% similarity on average, which could be compared with deposited sequences in public databases. The nucleotide distance between species belonging to different genera based on COI ranged from 0.17% between Sarotherodon melanotheron and Coptodon zillii to 0.49% between Clarias gariepinus and C. zillii, indicating that S. melanotheron and C. zillii are closely related. Based on the data obtained, the utility of COI gene was confirmed in accurate identification of three fish species from Southwest Nigeria.

Experimental exposure of African catfish Clarias Gariepinus (Burchell, 1822 to phenol: Clinical evaluation, tissue alterations and residue assessment

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Mai D. Ibrahem

2012-04-01

Full Text Available There is lack of information regarding; the toxicological and pathological consequences of phenol stressed Clarias gariepinus; as well as; the susceptibility of the stressed fish to disease occurrence. Static renewal bioassay was experimentally conducted to evaluate the toxic effects of phenol on the African catfish C. gariepinus. Ninety-six-hour acute toxicity tests revealed that the median lethal concentration of phenol (LC50 is 35 mg/L by immersion. Four experimental fish groups were assigned for 3 weeks exposure test; three were exposed 20%, 50% and 70% LC50, the fourth control fish group received a vehicle of dechlorinated water. Abnormal signs including cessation of feeding, nervous manifestations; skin expressed perfuses mucous, black patches with skin erosion and ulcerations in the later stages. All observations were correlated to the time and dose of exposure. Post mortem examination revealed adhesion of the internal organs. For tissue alterations; Skin, gills, brain, liver and kidney showed variable degrees of degenerative changes and necrosis. Muscle residues shown in mean ± SE were 4.3 ± 0.05 and 6.65 ± 0.05 ppm in groups that received 20 and 50% LD50, respectively. Infection with Aeromonas hydrophila resulted in high percent of mortalities with a non significant difference between the challenged fish groups. The study cleared that phenol is toxic to C. gariepinus under experimental conditions.

Effects of strains on growth performances of triploid bighead catfish, Clarias macrocephalus Günther, 1864

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Satid Chatchaiphan

2016-07-01

Full Text Available Despite its importance, limited empirical information is available on the effects of parental strains on the performance of triploid aquatic animals, especially of tropical species. The present study was conducted to evaluate the impacts of strains on the growth performance of the triploid bighead catfish (Clarias macrocephalus Günther, 1864 which was produced using cold shock (7 °C, 25 min shock duration, applied to newly fertilized eggs obtained from all possible crosses between two catfish strains. The fingerlings of each group were reared until they were age 240 d. At age 60 d, the triploid fish had a lower specific growth rate (SGR, absolute growth rate (AGR, body length and body weight than the diploid counterparts. However, at harvest (age 240 d body length and body weight were not different between the two groups while SGR of the cold shock group was higher than the diploid during age 121–240 d. The results revealed that parental strains did not show significant direct effects on the growth performance of triploids, but the interaction between paternal strain × shock was significant for the following traits: body length at age 90 d, body weight at age 90 d and 120 d, AGR for age 61–90 d, and SGR for age 61–90 d and 91–120 d. The interaction between paternal × maternal strain × shock was significant for body length, body weight at age 180 d and AGR for age 121–180 d. These results suggested that the growth performance of triploid C. macrocephalus cannot be enhanced by improving the parental strains; rather, improvement may be accomplished by selecting the parental strains based on triploid performance.

ENDOR determination of the proton positions around Gd3+ in La(C2H5SO4)3.9H2O

International Nuclear Information System (INIS)

Beer, R. de; Biesboer, F.; Ormondt, D. van

1976-01-01

The water proton positions around Gd 3+ in La(C 2 H 5 SO 4 ) 3 .9H 2 O have been determined by means of ENDOR. The positions of the nearest neighbour water oxygens are discussed on the basis of a superposition model analysis of the ratios b 2 0 /A 2 0 2 >, b 6 6 /b 6 0 and mod(A 6 6 )modA 6 0 . (Auth.)

Cardiorespiratory responses to hypoxia in the African catfish, Clarias gariepinus (Burchell 1822), an air-breathing fish.

Science.gov (United States)

Belão, T C; Leite, C A C; Florindo, L H; Kalinin, A L; Rantin, F T

2011-10-01

The African catfish, Clarias gariepinus, possesses a pair of suprabranchial chambers located in the dorsal-posterior part of the branchial cavity having extensions from the upper parts of the second and fourth gill arches, forming the arborescent organs. This structure is an air-breathing organ (ABO) and allows aerial breathing (AB). We evaluated its cardiorespiratory responses to aquatic hypoxia. To determine the mode of air-breathing (obligate or accessory), fish had the respiratory frequency (f (R)) monitored and were subjected to normoxic water (PwO(2) = 140 mmHg) without becoming hyperactive for 30 h. During this period, all fish survived without displaying evidences of hyperactivity and maintained unchanged f (R), confirming that this species is a facultative air-breather. Its aquatic O(2) uptake ([Formula: see text]) was maintained constant down to a critical PO(2) (PcO(2)) of 60 mmHg, below which [Formula: see text] declined linearly with further reductions of inspired O(2) tension (PiO(2)). Just above the PcO(2) the ventilatory tidal volume (V (T)) increased significantly along with gill ventilation ([Formula: see text]), while f (R) changed little. Consequently, the water convection requirement [Formula: see text] increased steeply. This threshold applied to a cardiac response that included reflex bradycardia. AB was initiated at PiO(2) = 140 mmHg (normoxia) and air-breathing episodes increased linearly with more severe hypoxia, being significantly higher at PiO(2) tensions below the PcO(2). Air-breathing episodes were accompanied by bradycardia pre air-breath, to tachycardia post air-breath.

Isolation and Identification of Aeromonas hydrophila and Saprolegnia sp. on Catfish (Clarias gariepinus) in Floating cages in Bozem Moro Krembangan Surabaya

Science.gov (United States)

Kusdarwati, Rahayu; Kismiyati; Sudarno; Kurniawan, Hendi; Teguh Prayogi, Yudha

2017-02-01

Catfish (Clarias gariepinus) is one of the familiar freshwater fish cultured in Indonesia farmer. One of the reason is the high mortality of the catfish infected by Aeromonas hydrophila and Saprolegnia sp. Motile Aeromonas septicemia (MAS) is a common bacterial disease, caused by Aeromonas hydrophila, which affects freshwater fish. In Southeast Asia, the outbreak of this disease was firstly reported from West Java in 1980, when a total of 82.5 tons a month of catfish were lost, while in Central Java in 1984, the total loss was 1.6 tons. Saprolegniosis can cause economic loss due to high mortality from its case reaching 10% to 50%. This research aimed to identify and determine the percentage of A. hydrophila and Saprolegnia sp. the catfish farmed in bozem Moro Krembangan, Surabaya, East Java. Meanwhile, a supporting parameter in this research is the value of water quality parameter including pH, temperature, ammonia and dissolved oxygen that were measured during sampling. The results showed that of the 20 samples taken from the two cages, 19 fish were positively infected by A. drophila. percentage of infections of A. hydrophila that infect umbo catfish in Moro Krembangan, was 95%, while the percentage Saprolegnia sp. was 90%.

WHAT IS THE REDSHIFT OF THE GAMMA-RAY BL LAC SOURCE S4 0954+65?

Energy Technology Data Exchange (ETDEWEB)

Landoni, M. [INAF—Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Brera, Via E. Bianchi 46, I-23807 Merate (Italy); Falomo, R. [INAF—Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy); Treves, A. [Universita’ degli Studi dell’Insubria, Via Valleggio 11, I-22100 (Italy); Scarpa, R.; Payá, D. Reverte, E-mail: marco.landoni@brera.inaf.it [Instituto de Astrofsica de Canarias, C/O Via Lactea, s/n E38205—La Laguna (Tenerife) (Spain)

2015-12-15

High signal-to-noise ratio spectroscopic observations of the BL Lac object S4 0954+65 at the alleged redshift z = 0.367 are presented. This source was detected at gamma frequencies by the MAGIC (TeV) and FERMI (GeV) telescopes during a remarkable outburst that occurred in 2015 February, making the determination of its distance particularly relevant for our understanding of the properties of the extragalactic background light. Contrary to previous reports on the redshift, we found that the optical spectrum is featureless at an equivalent width limit of ∼0.1 Å. A critical analysis of the existing observations indicates that the redshift is still unknown. Based on the new data we estimate a lower limit to the redshift at z ≥ 0.45.

Induced spawning, survival and growth of an African catfish hybrid ...

African Journals Online (AJOL)

Induced spawning, survival and growth of an African catfish hybrid (female Clarias gariepinus and male Clarias anguillaris ) fingerlings relative to their parental species in the mount Cameroon region.

Salinity-dependent nickel accumulation and effects on respiration, ion regulation and oxidative stress in the galaxiid fish, Galaxias maculatus.

Science.gov (United States)

Blewett, Tamzin A; Wood, Chris M; Glover, Chris N

2016-07-01

Inanga (Galaxias maculatus) are a euryhaline and amphidromous Southern hemisphere fish species inhabiting waters highly contaminated in trace elements such as nickel (Ni). Ni is known to exert its toxic effects on aquatic biota via three key mechanisms: inhibition of respiration, impaired ion regulation, and stimulation of oxidative stress. Inanga acclimated to freshwater (FW), 50% seawater (SW) or 100% SW were exposed to 0, 150 or 2000 μg Ni L(-1), and tissue Ni accumulation, metabolic rate, ion regulation (tissue ions, calcium (Ca) ion influx), and oxidative stress (catalase activity, protein carbonylation) were measured after 96 h. Ni accumulation increased with Ni exposure concentration in gill, gut and remaining body, but not in liver. Only in the gill was Ni accumulation affected by exposure salinity, with lower branchial Ni burdens in 100% and 50% SW inanga, relative to FW fish. There were no Ni-dependent effects on respiration, or Ca influx, and the only Ni-dependent effect on tissue ion content was on gill potassium. Catalase activity and protein carbonylation were affected by Ni, primarily in FW, but only at 150 μg Ni L(-1). Salinity therefore offsets the effects of Ni, despite minimal changes in Ni bioavailability. These data suggest only minor effects of Ni in inanga, even at highly elevated environmental Ni concentrations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Surface radiant flux densities inferred from LAC and GAC AVHRR data

Science.gov (United States)

Berger, F.; Klaes, D.

To infer surface radiant flux densities from current (NOAA-AVHRR, ERS-1/2 ATSR) and future meteorological (Envisat AATSR, MSG, METOP) satellite data, the complex, modular analysis scheme SESAT (Strahlungs- und Energieflüsse aus Satellitendaten) could be developed (Berger, 2001). This scheme allows the determination of cloud types, optical and microphysical cloud properties as well as surface and TOA radiant flux densities. After testing of SESAT in Central Europe and the Baltic Sea catchment (more than 400scenes U including a detailed validation with various surface measurements) it could be applied to a large number of NOAA-16 AVHRR overpasses covering the globe.For the analysis, two different spatial resolutions U local area coverage (LAC) andwere considered. Therefore, all inferred results, like global area coverage (GAC) U cloud cover, cloud properties and radiant properties, could be intercompared. Specific emphasis could be made to the surface radiant flux densities (all radiative balance compoments), where results for different regions, like Southern America, Southern Africa, Northern America, Europe, and Indonesia, will be presented. Applying SESAT, energy flux densities, like latent and sensible heat flux densities could also be determined additionally. A statistical analysis of all results including a detailed discussion for the two spatial resolutions will close this study.

Bioaccumulation of cadmium in an experimental aquatic food chain involving phytoplankton (Chlorella vulgaris), zooplankton (Moina macrocopa), and the predatory catfish Clarias macrocephalus x C. gariepinus

International Nuclear Information System (INIS)

Ruangsomboon, Suneerat; Wongrat, Ladda

2006-01-01

The accumulation of cadmium (Cd) was studied in an experimental aquatic food chain involving the phytoplankton Chlorella vulgaris as the primary producer, the zooplankton Moina macrocopa as the primary consumer, and the catfish Clarias macrocephalus x Clarias gariepinus as the secondary consumer. C. vulgaris was first exposed to Cd solutions at 0.00, 0.35, and 3.50 mg l -1 , referred to as control group and experimental groups 1 and 2, respectively. Subsequently, each group was fed to three corresponding groups of M. macrocopa. Finally, three groups of catfish were fed these corresponding groups of M. macrocopa. After C. vulgaris was exposed to 3.50 mg l -1 Cd (experimental group 2), the residual Cd in solution was only 4.01 μg l -1 , lower than the maximum allowable limit of Cd in natural water sources (5 μg l -1 ). Cd concentrations in C. vulgaris were 0.01 ± 0.00 μg g -1 (dry wt) in the control group, 194 ± 1.80 μg g -1 (dry wt) in experimental group 1, and 1140 ± 20.06 μg g -1 (dry wt) in experimental group 2. The Cd concentrations in M. macrocopa were 0.01 ± 0.00 μg g -1 (dry wt) in the control group, 16.48 ± 2.23 μg g -1 (dry wt) in experimental group 1, and 56.6 ± 3.23 μg g -1 (dry wt) in experimental group 2. The Cd concentrations in catfish muscle increased with increasing Cd concentrations in the food. After 60 days of fish culture, the mean concentrations of Cd in fish muscle were 0.01 ± 0.00 μg g -1 (dry wt) in the control group, 0.61 ± 0.02 μg g -1 (dry wt) in experimental group 1 and 1.04 ± 0.06 μg g -1 (dry wt) in experimental group 2. Cd concentration in fish muscle of experimental group 2 was equal to the permissible limit. Cd accumulation affected fish growth: at the end of the study, the mean fresh weight (12.81 g) of catfish in the control group, was significantly higher than those experimental group 1 (10.43 g) and experimental group 2 (10.00 g). The results showed that the measurement of Cd concentration in water does not

Bioaccumulation of cadmium in an experimental aquatic food chain involving phytoplankton (Chlorella vulgaris), zooplankton (Moina macrocopa), and the predatory catfish Clarias macrocephalus x C. gariepinus

Energy Technology Data Exchange (ETDEWEB)

Ruangsomboon, Suneerat [Faculty of Agricultural Technology, King Mongkut' s Institute of Technology Ladkrabang, Chalongkrung Road, Bangkok 10520 (Thailand)]. E-mail: krsuneer@kmitl.ac.th; Wongrat, Ladda [Faculty of Fishery, Kasetsart University, Bangkok 10900 (Thailand)

2006-06-10

The accumulation of cadmium (Cd) was studied in an experimental aquatic food chain involving the phytoplankton Chlorella vulgaris as the primary producer, the zooplankton Moina macrocopa as the primary consumer, and the catfish Clarias macrocephalus x Clarias gariepinus as the secondary consumer. C. vulgaris was first exposed to Cd solutions at 0.00, 0.35, and 3.50 mg l{sup -1}, referred to as control group and experimental groups 1 and 2, respectively. Subsequently, each group was fed to three corresponding groups of M. macrocopa. Finally, three groups of catfish were fed these corresponding groups of M. macrocopa. After C. vulgaris was exposed to 3.50 mg l{sup -1} Cd (experimental group 2), the residual Cd in solution was only 4.01 {mu}g l{sup -1}, lower than the maximum allowable limit of Cd in natural water sources (5 {mu}g l{sup -1}). Cd concentrations in C. vulgaris were 0.01 {+-} 0.00 {mu}g g{sup -1} (dry wt) in the control group, 194 {+-} 1.80 {mu}g g{sup -1} (dry wt) in experimental group 1, and 1140 {+-} 20.06 {mu}g g{sup -1} (dry wt) in experimental group 2. The Cd concentrations in M. macrocopa were 0.01 {+-} 0.00 {mu}g g{sup -1} (dry wt) in the control group, 16.48 {+-} 2.23 {mu}g g{sup -1} (dry wt) in experimental group 1, and 56.6 {+-} 3.23 {mu}g g{sup -1} (dry wt) in experimental group 2. The Cd concentrations in catfish muscle increased with increasing Cd concentrations in the food. After 60 days of fish culture, the mean concentrations of Cd in fish muscle were 0.01 {+-} 0.00 {mu}g g{sup -1} (dry wt) in the control group, 0.61 {+-} 0.02 {mu}g g{sup -1} (dry wt) in experimental group 1 and 1.04 {+-} 0.06 {mu}g g{sup -1} (dry wt) in experimental group 2. Cd concentration in fish muscle of experimental group 2 was equal to the permissible limit. Cd accumulation affected fish growth: at the end of the study, the mean fresh weight (12.81 g) of catfish in the control group, was significantly higher than those experimental group 1 (10.43 g) and

Chlorella vulgaris as Protein Source in the Diets of African Catfish Clarias gariepinus

Directory of Open Access Journals (Sweden)

Uchechukwu D. Enyidi

2017-10-01

Full Text Available Plant proteins substitutes of fishmeal in aquafeed are usually lacking in some essential amino acids and fatty acids. The microalgae Chlorella vulgaris has good-quality protein with amino acids rich in methionine, lysine and alanine. Four novel diets having C. vulgaris as the main source of protein were produced for African catfish Clarias gariepinus with an initial average weight of 1.09 ± 0.05 g. The diets were labeled Feed 1 (F1 to feed 4 (F4. The treatment diets were included 25% (F1, 15% (F2, 5% (F3 and 0% (F4 green algae meal. The basal ingredients of the feed were corn (maize included as F1, 40%, F2, 43%, F3, 53% and F4, 43%; and millet meal, which varied in F1 as 23%, F2, 30%, F3, 30% and F4, 30%. The ingredients were preconditioned at 110 °C and pelleted. Post-fingerling African catfish were stocked at 10 fish per aquarium. There were three replicate aquariums for each feed type and the fish were fed for 60 d. The specific growth rate was best for the catfish fed with 25% C. vulgaris diet 7.86 ± 0% day−1, and worst at 6.77 ± 0.07% day−1 for the control group F4, 0% algal meal. The food conversion ratio (FCR was lowest (1.88 ± 0.02 for 25% algal meal diet (F1 and highest (2.98 ± 0.01 for the 0% algal meal diet F4. Similarly, catfish had average weight gain of 121.02 ± 0.04 g for those fed with F1 compared to 62.50 ± 0.0 g for those fed with 0% algae F4. Protein efficiency ratio was highest for the F1-fed fish (2.46 ± 0.22 and lowest for those fed with F4 (2.02 ± 0.09. The hepatosomatic index was lowest for F1-fed fish (1.48 ± 0.01 and highest for catfish fed with F4 (2.50 ± 0.59. Based on the results, C. vulgaris is a good protein source for African catfish and can also substitute fishmeal in the catfish diets.

Toxicity of buprofezin on the survival of embryo and larvae of African catfish, Clarias gariepinus (Bloch).

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Marimuthu, Kasi; Muthu, Narmataa; Xavier, Rathinam; Arockiaraj, Jesu; Rahman, M Aminur; Subramaniam, Sreeramanan

2013-01-01

Buprofezin is an insect growth regulator and widely used insecticide in Malaysia. The present study evaluated the toxic effects of buprofezin on the embryo and larvae of African catfish (Clarias gariepinus) as a model organism. The embryos and larvae were exposed to 7 different concentrations (0, 0.05, 0.5, 5, 25, 50 and 100 mg/L) of buprofezin. Each concentration was assessed in five replicates. Eggs were artificially fertilized and 200 eggs and larvae were subjected to a static bath treatment for all the concentrations. The mortality of embryos was significantly increased with increasing buprofezin concentrations from 5 to 100 mg/L (pbuprofezin acute toxicity tests were evaluated using probit analysis. The 24 h LC50 value (with 95% confidence limits) of buprofezin for embryos was estimated to be 6.725 (3.167-15.017) mg/L. The hatching of fish embryos was recorded as 68.8, 68.9, 66.9, 66.4, 26.9, 25.1 and 0.12% in response to 7 different concentrations of buprofezin, respectively. The mortality rate of larvae significantly (pbuprofezin concentrations exposed to 24-48 h. The 24 and 48 h LC50 values (with 95% confidence limits) of buprofezin for the larvae was estimated to be 5.702 (3.198-8.898) and 4.642 (3.264-6.287) mg/L respectively. There were no significant differences (p>0.05) in the LC50 values obtained at 24 and 48 h exposure times. Malformations were observed when the embryos and larvae exposed to more than 5 mg/L. The results emerged from the study suggest that even the low concentration (5 mg/L) of buprofezin in the aquatic environment may have adverse effect on the early embryonic and larval development of African catfish.

Europa-Latinoamérica: amigos complicados. Sobre la IV EU-LAC en Viena, Austria

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Gerhard Drekonja-Kornat

2014-06-01

Full Text Available Para los presidentes latinoamericanos, las cumbres ya son rutina. Para Viena, la anfitriona de la IV reunión EU-LAC que se realizó del 11 al 13 de mayo de 2006, esta cumbre fue el acontecimiento del siglo. Se podría decir que fue la continuación del Congreso de Viena de 1815. Adecuadamente acicalada, se presentó la capital austriaca, a la cual después de Río, Madrid y Guadalajara, le tocó organizar la cuarta Cumbre de Jefes de Estado y de Gobierno de la Unión Europea, América Latina y el Caribe. Puesto que también se encontraban presentes los representantes de los países adherentes y candidatos a ingresar a la Unión –incluso el primer ministro de Turquía, R. T. Erdogan estuvo presente–, se tomó la tradicional “foto familiar” con 60 participantes.

A new gonad-infecting species of Philometra (Nematoda: Philometridae) from the Atlantic Spanish mackerel Scomberomorus maculatus (Scombridae) off the Atlantic Coast of Florida and South Carolina.

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Moravec, František; Bakenhaster, Micah; de Buron, Isaure

2013-04-01

A new nematode species, Philometra atlantica n. sp. (Philometridae), is described from male and female specimens found in the ovary of the Atlantic Spanish mackerel, Scomberomorus maculatus (Mitchill) (Scombridae, Perciformes), off the Atlantic coast of Florida and South Carolina. Based on light and scanning electron microscopy examination, the new species differs from most other gonad-infecting Philometra spp. in the length of spicules (111-126 μm), number and arrangement of genital papillae, and a U-shaped, dorsally interrupted caudal mound in the male. A unique feature among all gonad-infecting philometrids is the presence of 2 reflexed dorsal barbs on the distal end of the gubernaculum. From a few congeneric, gonad-infecting species with unknown males, it can be distinguished by some morphological and biometrical features found in gravid females (body length, length of first-stage larvae or esophagus, structure of caudal end) and by the host type (fish family) and geographical distribution. Philometra atlantica is the fourth valid gonad-infecting species of Philometra reported from fishes of the family Scombridae.

[Testicular testosterone production in male mice of inbred strains PT and CBA/Lac after a long-term period of stable social hierarchy].

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Osadchuk, L V; Gutorova, N V; Kleshchev, M A

2014-04-01

Social dominance can alter testicular testosterone production, although there is pronounced variability in the relationship between social status and pattern of the testosterone response. The study designed to investigate how a long-term period of stable social hierarchy effects on testicular testosterone production in male mice of inbred strains PT and CBA/Lac. Paired males of different genotypes were housed together for 32 days beginning 38 day of age. Dyadic interactions of males generated dominance-subordination relationships during the first day after a social group has been produced and the social rank of each opponent was assessed by asymmetry in agonistic behaviour. Serum level of testosterone and its testicular content were evaluated in male mice of both inbred strains at 70 day of age after pair housing. Control animals were age- and genotype-matched single males that were housed in conventional cages. After a long-term period of pair housing, the serum testosterone level and its testicular content in males of both PT and CBA/Lac strains were not significantly different from the control. There were no significant differences in androgenic parameters between social ranks in male mice of both strains. The results indicate that in laboratory mice the pattern of testicular testosterone response to social hierarchy determined by a social situation, for example, a stability of social interactions, when the importance of aggressive competition for rank is minimal.

Ultrasound-assisted synthesis of 2,4-thiazolidinedione and rhodanine derivatives catalyzed by task-specific ionic liquid: [TMG][Lac].

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Suresh; Sandhu, Jagir Singh

2013-03-03

Synthesized arylidene derivatives of rhodanine and 2,4-thiazolidiendione have potent pharmacological activities, and these are also key substrates for the preparation of clinically used antidiabetics. Some 1,1,3,3-tetramethylguanidine-based task-specific ionic liquids (TSILs) 1a-1e were prepared and employed to the catalyzed solvent-free Knoevenagel condensation of 2,4-thiazolidinedione 3a and rhodanine 3b with a variety of aldehydes. Best results were obtained with 1,1,3,3-tetramethylguanidine lactate ([TMG][Lac]) 1c. The TSIL used can be easily recovered and recycled, yielding products 4-5 in excellent yields under ultrasonic environment without the formation of any side products or toxic waste.

De Paris à Lyon. Les mutations éditoriales du «Lancelot du Lac»

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Gaëlle Burg

2015-07-01

Full Text Available Lancelot du Lac est le premier roman arthurien imprimé à la Renais­sance. Dans sa première édition parue en 1488, qui réunit deux imprimeurs (Jean Le Bourgeois à Rouen et Jean Du Pré à Paris, un découpage et un prologue inédits sont ajoutés par le remanieur. Le texte sera réédité six fois par divers imprimeurs-libraires parisiens jusqu’en 1533. L’édition de luxe d’Antoine Vérard (1494, destinée au roi Charles VIII, présente d’importantes modifications effectuées dans un but commercial. Après une longue période d’accalmie qui signe le début du déclin de la vogue des romans de chevalerie médiévaux, Benoît Rigaud publie à Lyon, sous une forme considérablement abrégée, la dernière édition connue du Lancelot au XVIe siècle (1591. Si elle ne présente que peu d’intérêt littéraire, elle apporte cependant des informations concernant les pratiques éditoriales et les goûts du  lecteur de la fin du XVIe siècle. De Paris à Lyon, entre renaissance et déclin, le parcours éditorial d’un incontournable roman arthurien.Lancelot du Lac is the editio princeps of an Arthurian romance in Renaissance France. The first edition in 1488, which brings together two printers (Jean Le Bourgeois from Rouen and Jean Du Pré from Paris, offers original arrangement and prologue added by the compositor. The text will be published six times by various printers and booksellers in Paris until 1533. The luxurious edition from Antoine Vérard (1494 dedicated to King Charles VIII provides interesting transformations in commercial purposes. After a long time without edition, showing the beginning of chivalry literature’s decline, Benoît Rigaud publish in Lyon, in a greatly abbreviated form, the last known edition of Lancelot in the XVIth century (1591. If it presents no literary interest, it provides nevertheless informations about editorial practices and reader’s tastes from the end of Renaissance France. From Paris to

Manoomin: place-based research with Native American students on wild rice lakes on the Fond du Lac Band of Lake Superior Chippewa Reservation, northern Minnesota

Science.gov (United States)

Ito, E.; Myrbo, A.; Dalbotten, D. M.; Pellerin, H.; Greensky, L.; Howes, T.; Wold, A.; McEathron, M. A.; Shanker, V.

2010-12-01

The manoomin project is a collaboration between Fond du Lac Tribal and Community College (Cloquet, MN), the Reservation’s Resource Management Division, and the University of Minnesota funded by the NSF GEO-OEDG Program. It builds on a successful seven-year history of collaboration between these parties, including regular science camps (gidaakiimanaanimigawig, Our Earth Lodge) for students of a wide range of ages. We are working as a team with Native students to study the history of wild rice (manoomin; Zizania palustris), a culturally important resource, growing on Reservation lakes. The joint project takes two main approaches: study of sediment core samples collected from Reservation lakes; and the collection of traditional knowledge about wild rice from the Elders. Science campers collect lake cores during winter with the assistance of the U of MN’s LacCore (National Lacustrine Core Facility) and Resource Management and visit LacCore to log, split and describe cores soon thereafter. Academic mentors with a range of specialties (phytoliths, pollen, plant macrofossils, sedimentology, geochemistry, magnetics) spend 1-2 weeks during the summer with small groups of college-age (>18, many nontraditional) student interns working on a particular paleoenvironmental proxy from the sediment cores. Younger students (middle and high school) also work in small teams in half day units with the same mentors. All campers become comfortable in an academic setting, gain experience working in research labs learning and practicing techniques, and jointly interpret collective results. The continuation of the project over five years (2009-2014) will allow these students to develop relationships with scientists and to receive mentoring beyond the laboratory as they make transitions into 2- and 4-year colleges and into graduate school. Their research provides historical and environmental information that is relevant to their own land that will be used by Resource Management which is

Effect of eugenol on the mutagenicity of benzo[a]pyrene and the formation of benzo[a]pyrene-DNA adducts in the X-lacZ-transgenic mouse.

NARCIS (Netherlands)

Rompelberg, C.J.M.; Steenwinkel, M.J.S.T.; Asten, J.G. van; Delft, J.H.M. van; Baan, R.A.; Verhagen, H.

1996-01-01

To study the possible reduction by eugenol of the mutagenicity and genotoxicity of benzoja]pyrene (B[a]P) in vivo, the X-lacZ-transgenic mouse strain 40.6 (Muta(TM)Mouse) was used. Male mice were fed a diet containing 0.4% (w/w) eugenol or a control diet for 58 days. On day 10, half of the mice

Evaluation of Local Feed Ingredients Based Diets on Growth Performance of African Catfish, Clarias gariepinus

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Farahiyah, I. J.

2016-12-01

Full Text Available Formulating the right feed based on the requirements of the fish species is the main solver to reduce the high cost of aquaculture production. In formulating suitable diet, factors such as the sustainability or availability of the feed sources used, quality of the feeds and price of raw materials, need to be taken into account as well so that the diets can be formulated at least cost. Low cost diets using local feed ingredients were formulated in pelleted and extruded forms and fed to juvenile African catfish, Clarias gariepinus, to determine their effect on the growth performance of the fish. Two formulations were tested: Diet A - Formula 1 MARDI and Diet B - Formula 2 MARDI, which were formulated to be iso-caloric and iso-nitrogenous with 32 % digestible protein and energy value of 14 MJ/kg. A commercial diet (Diet C was included as a control. At 15 wk of culture, fish fed diet C showed the highest growth performance in terms of weight gain, feed conversion ratio (FCR and specific growth rate (SGR. There were no significant differences (P>0.05 found among diets for weight gain and feed intake. However, FCR and SGR of Diet C were significantly better (P<0.05 compared to the experimental diets. The best FCR was recorded in Diet C at 1.17, followed by Diet A (1.42 and Diet B (1.46. Diet C also had the highest SGR with 1.99%/day followed by Diet B (1.70 and Diet A (1.67. Cost of both diets, A and B, was RM 2.50/kg compared to RM 3.50/kg for Diet C. Although the FCR of the commercial feed was lower than the experimental diets, the production cost of fish was RM4.11/kg for the commercial feed compared to RM 3.54-3.65/kg for the experimental diets. It is concluded that local feed ingredients can be used in formulating diets for catfish and they have no detrimental effect on the growth of African catfish.

Efficacy of Andrographis paniculata, Psidium guajava and Piper betle as Prevention on Motile Aeromonad Septicaemia Infection in African Catfish (Clarias sp.

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D. Wahjuningrum

2007-07-01

Full Text Available An effort to prevent Motile Aeromonad Septicaemia (MAS disease in African catfish (Clarias sp. performed using antibiotic was less safety and expensive ways.  An herbal medicine may be able to be a safety and cheap way to prevent of the MAS disease.  This study was conducted to determine efficacy of herbal medicine combination of sambiloto (Andrographis paniculata, daun jambu (Psidium guajava and daun sirih (Piper betle. Herbal medicines were mixed to diet and fish were fed on the diet containing the herbal medicine for 7 days of rearing.  The dosage of herbal medicine per 100 gram of diet was PI (1.0 g sambiloto, 0.75 g daun jambu and 0.25 g daun sirih, PII (1.0 g sambiloto,  0.50 g daun jambu,  0.50 g daun sirih, and PIII (1.0 g sambiloto, 0.25 g daun jambu, and 0.75 g daun sirih.  On 8th day, fish were injected intramuscularly with 1 ml of Aeromonas hydrophila (105 cfu/ml every 1 kg of fish.  Clinical symptom, feed response, fish weight, number of fish survive and visually changing of internal organs.  The results of study indicated that administration of herbal medicine A. paniculata, P. guajava and P. betle mixed into the diet effectively prevented A. hydrophila infection.  Combination of 1.0 gram A. paniculata, 0.75 gram P. guajava and 0.25 gram P. betle gave higher efficacy against A. hydrophila infection. Keywords: Andrographis paniculata, Psidium guajava, Piper betle, Motile Aeromonad septicaemia, African catfish   ABSTRAK Upaya penanggulangan penyakit MAS (Motil Aeromonad Septicaemia pada ikan lele dumbo (Clarias sp. yang dilakukan menggunakan antibiotik cenderung kurang aman dan mahal. Pencegahan menggunakan obat herbal diharapkan dapat mengatasi masalah tersebut secara aman dan murah.  Penelitian ini dilakukan untuk mengetahui efektivitas obat herbal kombinasi sambiloto (Andrographis paniculata, daun jambu biji (Psidium guajava dan sirih (Piper betle dengan dosis berbeda yang diberikan melalui pakan selama 7 hari. �

Preliminary use of cashew kernel oil in Clarias gariepinus fingerlings diet: comparison with fish oil and palm oil

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Morgane Paul Magouana Anvo

2017-04-01

Full Text Available Abstract The present study was performed to investigate the effect of fish oil (FO, palm oil (PO, and cashew kernel oil (CKO as the dietary lipid sources on the growth performance, tissues fatty acids composition and economical profitability in Clarias gariepinus fingerlings. Three isonitrogenous (49.32%, isolipidic (15.18%, and isoenergetic (21 kJ/g diets were formulated, differed only to the added lipid source and coded accordingly as D1 (fish oil, D2 (palm oil, and D3 (cashew kernel oil. Catfish fingerlings (initial body weight = 2.43 ± 0.04 g were stocked at 1 fish/L and fed to trial diets at 5.6%. At the end of 8 weeks, C. gariepinus fingerlings fed with D1 and D3 had significantly identical growth and feed utilization efficiency. Those fed with D2 exhibited significantly and numerically low growth performance compared, respectively, to D1 and D3. Contrary to whole-body composition of fish, the muscle lipids fatty acids composition was influenced by the fatty acids profile of the dietary lipid sources. High net profit value (NPV of 24.59$, high investment cost analysis (ICA of 10.14$ and low benefit: cost ratio (BCR of 2.42 were observed in fish fed with D1 while those fed with D3 allowed to have high NPV (23.15$, low ICA (7.86$ and high BCR (2.95. Like others vegetable oils, cashew kernel oil can replace expensive fish oil in C. gariepinus fingerlings diet without negatively affecting its growth performances.

Waveband specific transcriptional control of select genetic pathways in vertebrate skin (Xiphophorus maculatus).

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Walter, Ronald B; Boswell, Mikki; Chang, Jordan; Boswell, William T; Lu, Yuan; Navarro, Kaela; Walter, Sean M; Walter, Dylan J; Salinas, Raquel; Savage, Markita

2018-05-10

Evolution occurred exclusively under the full spectrum of sunlight. Conscription of narrow regions of the solar spectrum by specific photoreceptors suggests a common strategy for regulation of genetic pathways. Fluorescent light (FL) does not possess the complexity of the solar spectrum and has only been in service for about 60 years. If vertebrates evolved specific genetic responses regulated by light wavelengths representing the entire solar spectrum, there may be genetic consequences to reducing the spectral complexity of light. We utilized RNA-Seq to assess changes in the transcriptional profiles of Xiphophorus maculatus skin after exposure to FL ("cool white"), or narrow wavelength regions of light between 350 and 600 nm (i.e., 50 nm or 10 nm regions, herein termed "wavebands"). Exposure to each 50 nm waveband identified sets of genes representing discrete pathways that showed waveband specific transcriptional modulation. For example, 350-400 or 450-500 nm waveband exposures resulted in opposite regulation of gene sets marking necrosis and apoptosis (i.e., 350-400 nm; necrosis suppression, apoptosis activation, while 450-500 nm; apoptosis suppression, necrosis activation). Further investigation of specific transcriptional modulation employing successive 10 nm waveband exposures between 500 and 550 nm showed; (a) greater numbers of genes may be transcriptionally modulated after 10 nm exposures, than observed for 50 nm or FL exposures, (b) the 10 nm wavebands induced gene sets showing greater functional specificity than 50 nm or FL exposures, and (c) the genetic effects of FL are primarily due to 30 nm between 500 and 530 nm. Interestingly, many genetic pathways exhibited completely opposite transcriptional effects after different waveband exposures. For example, the epidermal growth factor (EGF) pathway exhibits transcriptional suppression after FL exposure, becomes highly active after 450-500 nm waveband exposure, and again, exhibits strong

On the Redshift of TeV BL Lac Objects

Energy Technology Data Exchange (ETDEWEB)

Paiano, Simona; Falomo, Renato [INAF, Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5 I-35122 Padova (PD) (Italy); Landoni, Marco; Righi, Chiara [INAF, Osservatorio Astronomico di Brera, Via E. Bianchi 46 I-23807 Merate (Italy); Treves, Aldo [Università degli Studi dell’Insubria, Via Valleggio 11 I-22100 Como (Italy); Scarpa, Riccardo [Instituto de Astrofisica de Canarias, C/O Via Lactea, s/n E38205—La Laguna (Tenerife) (Spain)

2017-03-10

We report results of a spectroscopic campaign carried out at the 10 m Gran Telescopio Canarias for a sample of 22 BL Lac objects detected (or candidates) at TeV energies, aiming to determine or constrain their redshift. This is of fundamental importance for the interpretation of their emission models and for population studies and is also mandatory for studying the interaction of high-energy photons with the extragalactic background light using TeV sources. Optical spectra with high signal-to-noise ratios in the range 4250–10000 Å were obtained to search for faint emission or absorption lines from both the host galaxy and the nucleus. We determine a new redshift for PKS 1424+240 ( z = 0.604) and a tentative one for 1ES 0033+595 ( z = 0.467). We are able to set new spectroscopic redshift lower limits for three other sources on the basis of Mg ii and Ca ii intervening absorption features: BZB J1243+3627 ( z > 0.483), BZB J1540+8155 ( z > 0.672), and BZB 0J2323+4210 ( z > 0.267). We confirm previous redshift estimates for four blazars: S3 0218+357 ( z = 0.944), 1ES 1215+303 ( z = 0.129), W Comae ( z = 0.102), and MS 1221.8+2452 ( z = 0.218). For the remaining targets, in seven cases (S2 0109+22, 3C 66A, VER J0521+211, S4 0954+65, BZB J1120+4214, S3 1227+25, BZB J2323+4210), we do not validate the proposed redshift. Finally, for all sources of still-unknown redshift, we set a lower limit based on the minimum equivalent width of absorption features expected from the host galaxy.

Karakteristik Enzim Digesti, Protease dan Amilase, Ikan Gurami (Osphronemus gouramy Lac. pada Fase Pertumbuhan

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Untung Susilo

2015-05-01

Full Text Available Suatu penelitian untuk mengetahui karakteristik enzim digesti, protease dan amilase pada ikan gurami, Osphronemus gouramy Lac., telah dilakukan dengan metode survey. Jumlah ikan yang digunakan untuk penelitian sebanyak 25 ekor yang dikelompokan menjadi tiga kelompok ukuran13,29, 35,86 dan 91,86 g/ekor. Hasil penelitian menunjukkan bahwa aktivitas protease digesti ikan gurami berbeda secara signifikan pada segmen usus dan pH buffer yang berbeda (P.05, namun berbeda secara signifikan diantara ukuran ikan yang berbeda (P<.05, dan aktivitas amilase tertinggi dijumpai pada ikan dengan ukuran terkecil. Kesimpulan yang dapat diambil adalah bahwa aktivitas protease dan amilase dijumpai sepanjang saluran digestinya baik pada ikan yang berukuran kecil maupun besar. Aktivitas protease umumnya tinggi pada suasana asam dan netral pada usus depan dan tengah. Aktivitas protease ikan yang berukuran besar lebih rendah dari pada ikan yang berukuran lebih kecil. Aktivitas amilase tidak terdapat perbedaan diantara segmen usus yang diuji, namun aktivitas amilase tertinggi dijumpai pada ikan dengan berat rata-rata 13,29 g/ekor

Metallothionein from Wild Populations of the African Catfish Clarias gariepinus: From Sequence, Protein Expression and Metal Binding Properties to Transcriptional Biomarker of Metal Pollution

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Ethel M’kandawire

2017-07-01

Full Text Available Anthropogenic pollution with heavy metals is an on-going concern throughout the world, and methods to monitor release and impact of heavy metals are of high importance. With a view to probe its suitability as molecular biomarker of metal pollution, this study has determined a coding sequence for metallothionein of the African sharptooth catfish Clarias gariepinus. The gene product was recombinantly expressed in Escherichia coli in presence of Zn(II, Cd(II, or Cu, and characterised by Electrospray Ionisation Mass Spectrometry and elemental analysis. C. gariepinus MT displays typical features of fish MTs, including 20 conserved cysteines, and seven bound divalent cations (Zn(II or Cd(II when saturated. Livers from wild C. gariepinus fish collected in all three seasons from four different sites on the Kafue River of Zambia were analysed for their metal contents and for MT expression levels by quantitative PCR. Significant correlations were found between Zn and Cu levels and MT expression in livers, with MT expression clearly highest at the most polluted site, Chililabombwe, which is situated in the Copperbelt region. Based on our findings, hepatic expression of MT from C. gariepinus may be further developed as a major molecular biomarker of heavy metal pollution resulting from mining activities in this region.

Metallothionein from Wild Populations of the African Catfish Clarias gariepinus: From Sequence, Protein Expression and Metal Binding Properties to Transcriptional Biomarker of Metal Pollution.

Science.gov (United States)

M'kandawire, Ethel; Mierek-Adamska, Agnieszka; Stürzenbaum, Stephen R; Choongo, Kennedy; Yabe, John; Mwase, Maxwell; Saasa, Ngonda; Blindauer, Claudia A

2017-07-18

Anthropogenic pollution with heavy metals is an on-going concern throughout the world, and methods to monitor release and impact of heavy metals are of high importance. With a view to probe its suitability as molecular biomarker of metal pollution, this study has determined a coding sequence for metallothionein of the African sharptooth catfish Clarias gariepinus . The gene product was recombinantly expressed in Escherichia coli in presence of Zn(II), Cd(II), or Cu, and characterised by Electrospray Ionisation Mass Spectrometry and elemental analysis. C. gariepinus MT displays typical features of fish MTs, including 20 conserved cysteines, and seven bound divalent cations (Zn(II) or Cd(II)) when saturated. Livers from wild C. gariepinus fish collected in all three seasons from four different sites on the Kafue River of Zambia were analysed for their metal contents and for MT expression levels by quantitative PCR. Significant correlations were found between Zn and Cu levels and MT expression in livers, with MT expression clearly highest at the most polluted site, Chililabombwe, which is situated in the Copperbelt region. Based on our findings, hepatic expression of MT from C. gariepinus may be further developed as a major molecular biomarker of heavy metal pollution resulting from mining activities in this region.

A new pale-spotted species of Hypostomus Lacépède (Siluriformes: Loricariidae from the rio Tocantins and rio Xingu basins in central Brazil

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Cláudio H. Zawadzki

Full Text Available A new species of the genus Hypostomus Lacépède (Siluriformes, Loricariidae from rio Tocantins and rio Xingu basins in central Brazil, is described. The new species is distinguished from its congeners by a unique combination of pale blotches over a darker background on head, body and fins, and conspicuous keels on head, predorsal region and lateral plates. Comments on the pale-spotted species of Hypostomus are provided.

Parasitic diseases and heavy metal analysis in Parachanna obscura (Gunther 1861 and Clarias gariepinus (Burchell 1901 from Epe Lagoon, Lagos, Nigeria

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Akinsanya Bamidele

2016-09-01

Full Text Available Objective: To evaluate the bioaccumulation of heavy metals in Parachanna obscura (P. obscura and Clarias gariepinus (C. gariepinus and the use of their parasites as accumulation indicators from Lekki Lagoon. Methods: Samples of fish were procured from Oluwo market, a landing site of fish of artisanal fishermen in Epe. Metal accumulation, and intestinal parasites and protozoan of P. obscura and C. gariepinus were investigated. Sediment and water samples were examined for selected heavy metals (Cu, Cr, Ni, Pb and Fe while nematode parasite from infected fish were also analysed for heavy metal content. Results: Absolute morphometric parameters had low correlation with single independent morphometric index (total length and standard length but increased when correlated with combined indices. The prevalence of parasitic infections in P. obscura and C. gariepinus were 35% and 36% respectively. The metal concentrations accumulated in the fish’s liver were more than that found in the water and sediment. There was strong correlation in metal accumulated in the parasites relative to the water medium (r = 0.968 - 1.000, P < 0.01. Procamallanus spp., a nematode accumulated 2 times more Cu, Cr, Ni, Pb and Fe than Wenyonia sp. There was higher heavy metal level observed in intestinal nematode Procamallanus sp. than wenyonia sp. in the infected fish in this study. Conclusions: This suggests that Procamallanus sp. may be used as a potential sink of metal pollution in an aquatic environment and also a good sentinel in the environment.

A Comparative Study of the Common Protozoan Parasites of Clarias gariepinus from the Wild and Cultured Environments in Benue State, Nigeria

Science.gov (United States)

Omeji, S.; Solomon, S. G.; Idoga, E. S.

2011-01-01

A total of one hundred and twenty Clarias gariepinus comprising 30 dead and 30 live fishes were examined for protozoan parasites infestation, sixty each from the wild and a pond (cultured environment) over a period of six months. Ichthyophthirius multifiliis was the most common protozoan parasites found in C. gariepinus from the wild (River Benue) and cultured (pond) environments. These protozoan parasites constitute 37.08% of the total parasites encountered for fishes in the pond and 42.51% of fishes in the wild. Among the body parts of the sampled fishes from the pond, the gills had the highest parasite load (38.86%). Also, the gills had the highest parasite load (40.54%) among the body parts of the fishes sampled from the wild. Fishes not infested with any protozoan parasites from the pond constituted 36.70% of the total fish sampled. On the other hand, fishes not infested with any protozoan parasites from the wild constituted 31.65% of the total fish sampled. Female fishes had more protozoan parasites than the male fishes. Bigger fishes of total length (25–48 cm) had more parasite load than the smaller ones (19–24 cm). Also, fishes between 150–750 g had more parasite load than the smaller ones of less than 150 g. Protozoan parasite load of fish from the cultured environment (pond) did not differ significantly (P < 0.05) from those from River Benue (wild). PMID:22028952

A Comparative Study of the Common Protozoan Parasites of Clarias gariepinus from the Wild and Cultured Environments in Benue State, Nigeria

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S. Omeji

2011-01-01

Full Text Available A total of one hundred and twenty Clarias gariepinus comprising 30 dead and 30 live fishes were examined for protozoan parasites infestation, sixty each from the wild and a pond (cultured environment over a period of six months. Ichthyophthirius multifiliis was the most common protozoan parasites found in C. gariepinus from the wild (River Benue and cultured (pond environments. These protozoan parasites constitute 37.08% of the total parasites encountered for fishes in the pond and 42.51% of fishes in the wild. Among the body parts of the sampled fishes from the pond, the gills had the highest parasite load (38.86%. Also, the gills had the highest parasite load (40.54% among the body parts of the fishes sampled from the wild. Fishes not infested with any protozoan parasites from the pond constituted 36.70% of the total fish sampled. On the other hand, fishes not infested with any protozoan parasites from the wild constituted 31.65% of the total fish sampled. Female fishes had more protozoan parasites than the male fishes. Bigger fishes of total length (25–48 cm had more parasite load than the smaller ones (19–24 cm. Also, fishes between 150–750 g had more parasite load than the smaller ones of less than 150 g. Protozoan parasite load of fish from the cultured environment (pond did not differ significantly (P<0.05 from those from River Benue (wild.

Haemoglobin polymorphism in wild and cultured African catfish ...

African Journals Online (AJOL)

Haemoglobin polymorphism, haemoglobin concentration, blood group and genotypes of wild and cultured Clarias gariepinus were investigated. Blood samples of Clarias gariepinus collected from Lake Alau (wild) and Dalori fish farm (cultured) were subjected to cellulose acetate electrophoresis to reveal the activities of ...

Complete Genomes of Bacillus coagulans S-lac and Bacillus subtilis TO-A JPC, Two Phylogenetically Distinct Probiotics.

Science.gov (United States)

Khatri, Indu; Sharma, Shailza; Ramya, T N C; Subramanian, Srikrishna

2016-01-01

Several spore-forming strains of Bacillus are marketed as probiotics due to their ability to survive harsh gastrointestinal conditions and confer health benefits to the host. We report the complete genomes of two commercially available probiotics, Bacillus coagulans S-lac and Bacillus subtilis TO-A JPC, and compare them with the genomes of other Bacillus and Lactobacillus. The taxonomic position of both organisms was established with a maximum-likelihood tree based on twenty six housekeeping proteins. Analysis of all probiotic strains of Bacillus and Lactobacillus reveal that the essential sporulation proteins are conserved in all Bacillus probiotic strains while they are absent in Lactobacillus spp. We identified various antibiotic resistance, stress-related, and adhesion-related domains in these organisms, which likely provide support in exerting probiotic action by enabling adhesion to host epithelial cells and survival during antibiotic treatment and harsh conditions.

Genetic Relatedness of Salmonella Serovars Isolated from Catfish (Clarias gariepinus) and Tilapia (Tilapia mossambica) Obtained from Wet Markets and Ponds in Penang, Malaysia.

Science.gov (United States)

Budiati, Titik; Rusul, Gulam; Wan-Abdullah, Wan Nadiah; Chuah, Li-Oon; Ahmad, Rosma; Thong, Kwai Lin

2016-04-01

A total of 43 Salmonella enterica isolates belonging to different serovars (Salmonella Albany, Salmonella Agona, Salmonella Corvallis, Salmonella Stanley, Salmonella Typhimurium, Salmonella Mikawasima, and Salmonella Bovismorbificans) were isolated from catfish (Clarias gariepinus) and tilapia (Tilapia mossambica) obtained from nine wet markets and eight ponds in Penang, Malaysia. Thirteen, 19, and 11 isolates were isolated from 9 of 32 catfish, 14 of 32 tilapia, and 11 of 44 water samples, respectively. Fish reared in ponds were fed chicken offal, spoiled eggs, and commercial fish feed. The genetic relatedness of these Salmonella isolates was determined by random amplified polymorphic DNA PCR (RAPD-PCR) using primer OPC2, repetitive extragenic palindromic PCR (REP-PCR), and pulsed-field gel electrophoresis (PFGE). Composite analysis of the RAPD-PCR, REP-PCR, and PFGE results showed that the Salmonella serovars could be differentiated into six clusters and 15 singletons. RAPD-PCR differentiated the Salmonella isolates into 11 clusters and 10 singletons, while REP-PCR differentiated them into 4 clusters and 1 singleton. PFGE differentiated the Salmonella isolates into seven clusters and seven singletons. The close genetic relationship of Salmonella isolates from catfish or tilapia obtained from different ponds, irrespective of the type of feed given, may be caused by several factors, such as the quality of the water, density of fish, and size of ponds.

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African Journals Online (AJOL)

Tissue glucose and haemoglobin levels in the catfish Clarias albopunctatus during anaesthesia with ketamine hydrochloride. Abstract · Vol 8, No 3 (2011) - Articles Histopathological effects of diethyl phthalate on Clarias gariepinus juveniles. Abstract. ISSN: 1597-3115. AJOL African Journals Online. HOW TO USE AJOL.

The potential for using red claw crayfish and hybrid African catfish as biological control agents for Schistosoma host snails

NARCIS (Netherlands)

Monde, C.; Syampungani, S.; Rico, A.; Brink, van den P.J.

2017-01-01

The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After

Deekae, SN

African Journals Online (AJOL)

Investigations on the Potential of Indian Almond Tree (Terminalia catappa) Leaf Extracts as Anaesthetic Agent in African Catfish (Clarias gariepinus) Abstract · Vol 29, No 1 (2014) - Articles Anaesthetic Efficacy of Sodium Bicarbonate and its Effects on the Blood Parameters of African Catfish, Clarias gariepinus (Burchell, ...

Author Details

African Journals Online (AJOL)

Investigations on the Potential of Indian Almond Tree (Terminalia catappa) Leaf Extracts as Anaesthetic Agent in African Catfish (Clarias gariepinus) Abstract · Vol 29, No 1 (2014) - Articles Anaesthetic Efficacy of Sodium Bicarbonate and its Effects on the Blood Parameters of African Catfish, Clarias gariepinus (Burchell, ...

Efficacy of some synthetic antibiotics on Streptococcus pneumoniae ...

African Journals Online (AJOL)

Effects of some synthetic antibiotics on Streptococcus pnemoniae and Proteus mirabilis isolated from cultured Clarias gariepinus, an important food fish raised in a concrete tank was carried out to ascertain their remedies on mortalities of the Clarias gariepinus adult fish. Streptococcus pnemoniae and Proteus mirabilis were ...

Variable quasi-stellar sources with particular emphasis on objects of the BL Lac type

International Nuclear Information System (INIS)

Kinman, T.D.

1975-01-01

The optically variable quasars tend to have steep optical spectra and to show variable polarization; they tend to be associated with compact radio sources which have flat radio spectra at GHz frequencies. Objects are known which have continuous spectra (like BL Lac and OJ 287), but whose other properties closely parallel those of the variable quasars and N galaxies; in fact no sharp distinction can be drawn between them. The variation in the visibility of emission lines in quasars and N galaxies could be due to variations in the strength and spectral index of the radiation from the non-thermal source and from the differences in the amount and disposition of the material around it; it does not seem likely that a combination of these factors accounts for the observed range in emission line strength. The systematic difference in optical spectral index between continuous-spectrum objects (and OVV variables) on the one hand and those with emission lines on the other will produce a difference in K term between them, which may be expected to affect their distributions with respect to apparent magnitude. (Auth.)

Complete Genomes of Bacillus coagulans S-lac and Bacillus subtilis TO-A JPC, Two Phylogenetically Distinct Probiotics

Science.gov (United States)

Ramya, T. N. C.; Subramanian, Srikrishna

2016-01-01

Several spore-forming strains of Bacillus are marketed as probiotics due to their ability to survive harsh gastrointestinal conditions and confer health benefits to the host. We report the complete genomes of two commercially available probiotics, Bacillus coagulans S-lac and Bacillus subtilis TO-A JPC, and compare them with the genomes of other Bacillus and Lactobacillus. The taxonomic position of both organisms was established with a maximum-likelihood tree based on twenty six housekeeping proteins. Analysis of all probiotic strains of Bacillus and Lactobacillus reveal that the essential sporulation proteins are conserved in all Bacillus probiotic strains while they are absent in Lactobacillus spp. We identified various antibiotic resistance, stress-related, and adhesion-related domains in these organisms, which likely provide support in exerting probiotic action by enabling adhesion to host epithelial cells and survival during antibiotic treatment and harsh conditions. PMID:27258038

Complete Genomes of Bacillus coagulans S-lac and Bacillus subtilis TO-A JPC, Two Phylogenetically Distinct Probiotics.

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Indu Khatri

Full Text Available Several spore-forming strains of Bacillus are marketed as probiotics due to their ability to survive harsh gastrointestinal conditions and confer health benefits to the host. We report the complete genomes of two commercially available probiotics, Bacillus coagulans S-lac and Bacillus subtilis TO-A JPC, and compare them with the genomes of other Bacillus and Lactobacillus. The taxonomic position of both organisms was established with a maximum-likelihood tree based on twenty six housekeeping proteins. Analysis of all probiotic strains of Bacillus and Lactobacillus reveal that the essential sporulation proteins are conserved in all Bacillus probiotic strains while they are absent in Lactobacillus spp. We identified various antibiotic resistance, stress-related, and adhesion-related domains in these organisms, which likely provide support in exerting probiotic action by enabling adhesion to host epithelial cells and survival during antibiotic treatment and harsh conditions.

Comparative Study of Commercial Feeds and Farm-made Aqua ...

African Journals Online (AJOL)

A feeding trial was conducted to compare the performance of Clarias gariepinus on four commercial catfish feeds and an on-farm aquafeed. The four catfish commercial diets were Coppens, Superindo and Chi manufactured in the Netherland, Indonesia and Nigeria respectively. 10 fingerlings of Clarias gariepinus (0.87 ...

Transcription of two adjacent carbohydrate utilization gene clusters in Bifidobacterium breve UCC2003 is controlled by LacI- and repressor open reading frame kinase (ROK)-type regulators.

Science.gov (United States)

O'Connell, Kerry Joan; Motherway, Mary O'Connell; Liedtke, Andrea; Fitzgerald, Gerald F; Paul Ross, R; Stanton, Catherine; Zomer, Aldert; van Sinderen, Douwe

2014-06-01

Members of the genus Bifidobacterium are commonly found in the gastrointestinal tracts of mammals, including humans, where their growth is presumed to be dependent on various diet- and/or host-derived carbohydrates. To understand transcriptional control of bifidobacterial carbohydrate metabolism, we investigated two genetic carbohydrate utilization clusters dedicated to the metabolism of raffinose-type sugars and melezitose. Transcriptomic and gene inactivation approaches revealed that the raffinose utilization system is positively regulated by an activator protein, designated RafR. The gene cluster associated with melezitose metabolism was shown to be subject to direct negative control by a LacI-type transcriptional regulator, designated MelR1, in addition to apparent indirect negative control by means of a second LacI-type regulator, MelR2. In silico analysis, DNA-protein interaction, and primer extension studies revealed the MelR1 and MelR2 operator sequences, each of which is positioned just upstream of or overlapping the correspondingly regulated promoter sequences. Similar analyses identified the RafR binding operator sequence located upstream of the rafB promoter. This study indicates that transcriptional control of gene clusters involved in carbohydrate metabolism in bifidobacteria is subject to conserved regulatory systems, representing either positive or negative control.

Dating fractures and fracture movement in the Lac du Bonnet Batholith

International Nuclear Information System (INIS)

Gascoyne, M.; Brown, A.; Ejeckam, R.B.; Everitt, R.A.

1997-04-01

This report examines and summarizes all work that has been done from 1980 to the present in determining the age of rock crystallization, fracture initiation, fracture reactivation and rates of fracture movement in the Lac du Bonnet Batholith to provide information for Atomic Energy of Canada Limited's (AECL) Canadian Nuclear Fuel Waste Management Program. Geological and petrographical indicators of relative age (e.g. cross-cutting relationships, sequences of fracture infilling minerals, P-T characteristics of primary and secondary minerals) are calibrated with radiometric age determinations on minerals and whole rock samples, using 87 Rb- 87 Sr, 40 K- 39 Ar, 40 Ar- 39 Ar and fission track methods. Most fractures and fracture zones inclined at low angles are found to be ancient features, first formed in the Early Proterozoic under conditions of deuteric alteration. Following some movement on fractures in the Late Proterozoic and Early Paleozoic, reactivation of fractures during the Pleistocene is established from uranium-series dating methods and use of stable isotopic contents of fracture infilling minerals (mainly calcite). Some indication of movement on fracture zones during the Pleistocene is given by electron spin resonance dating techniques on fault gouge. The slow rate of propagation of fractures is indicated by mineral infillings, their P-T characteristics and U-series calcite ages in a fracture in sparsely fractured rock, accessible from AECL's Underground Research Laboratory. These results collectively indicate that deep fractures observed in the batholith are ancient features and the fracturing and jointing in the upper 200 m is relatively recent (< 1 Ma) and largely a result of stress release. (author)

Death by desiccation: Effects of hermetic storage on cowpea bruchids

KAUST Repository

Murdock, Larry L.

2012-04-01

When cowpea grain is stored in airtight containers, destructive populations of the cowpea bruchid (. Callosobruchus maculatus) don\\'t develop even though the grain put into the store is already infested with sufficient . C. maculatus to destroy the entire store within a few months. The surprising effectiveness of hermetic storage for preserving grain against insect pests has long been linked with the depletion of oxygen in the hermetic container and with the parallel rise in carbon dioxide. With . C. maculatus, low oxygen (hypoxia) leads to cessation of larval feeding activity, whereas elevated levels of carbon dioxide (hypercarbia) have little or no effect on feeding. Cessation of feeding arrests the growth of the insects, which don\\'t mature and don\\'t reproduce. As a result, population growth ceases and damaging infestations don\\'t develop. . C. maculatus eggs, larvae, and pupae subjected to hypoxia eventually die after exposures of various duration. The cause of death is desiccation resulting from an inadequate supply of water. We demonstrate that blocking the supply of oxygen interdicts the main supply of water for . C. maculatus. This leads to inactivity, cessation of population growth, desiccation and eventual death. © 2012 Elsevier Ltd.

Commercial African Catfish (Clarias gariepinus Recirculating Aquaculture Systems: Assessment of Element and Energy Pathways with Special Focus on the Phosphorus Cycle

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Sebastian Marcus Strauch

2018-05-01

Full Text Available The reuse of effluent waters and sediments from African catfish (Clarias gariepinus recirculation aquaculture systems requires a deeper understanding of the nutrient and energy flows and material pathways. Three semi-commercial systems, differing in stocking density, were sampled for nutritive and pollutant elements of the input- (tap water, feed and output pathways (fillet, carcass, process water, sediments by ICP-OES/MS and calorimetry. Highly water-soluble elements, e.g., potassium, accumulated in the water, whereas iron, copper, chromium and uranium where found in the solids. Feed derived phosphorous was accounted for, 58.3–64.2% inside the fish, 9.7–19.3% in sediments, and small amounts 9.6–15.5% in the process waters. A total of 7.1–9.9% of the feed accumulated as dry matter in the sediments, comprising 5.5–8.7% total organic carbon and 3.7–5.2% nitrogen. A total of 44.5–47.1% of the feed energy was found in the fish and 5.7–7.7% in the sediments. For reuse of water and nutrients in hydroponics, the macro-nutrients potassium, nitrate, phosphorus and the micro-nutrient iron were deficient when compared with generalized recommendations for plant nutrition. Low energy contents and C/N-ratio restrict the solely use of African catfish solids for biogas production or vermiculture. Using the outputs both for biogas supplement and general fertilizer in aquaponics farming (s.l. (combined with additional nutrients appears possible.

SOME ASPECTS OF THE BIOLOGY AND CONTROL OF ...

African Journals Online (AJOL)

Key Words: Callosobruchus maculatus, developmental period, soya bean, Azadirachta indica, Citrus sinensis. ASPECTS DE LA BIOLOGIE ET DU CONTROLE DU CALLOSOBRUCHUS MACULATUS (F.) SUR LA CONSERVATION DES GRAINES DE SOJA DES VARIETES GLYCINE MAX (L.) MERR NOTE DE SYNTHESE

Redshift determination of the BL Lac object 3C 66A by the detection of its host galaxy cluster at z = 0.340

Science.gov (United States)

Torres-Zafra, Juanita; Cellone, Sergio A.; Buzzoni, Alberto; Andruchow, Ileana; Portilla, José G.

2018-03-01

The BL Lac object 3C 66A is one of the most luminous extragalactic sources at TeV γ-rays (very high energy, i.e. E > 100 GeV). Since TeV γ-ray radiation is absorbed by the extragalactic background light (EBL), it is crucial to know the redshift of the source in order to reconstruct its original spectral energy distribution, as well as to constrain EBL models. However, the optical spectrum of this BL Lac is almost featureless, so a direct measurement of z is very difficult; in fact, the published redshift value for this source (z = 0.444) has been strongly questioned. Based on EBL absorption arguments, several constraints to its redshift, in the range 0.096 GMOS-N multi-object spectroscopy. We found spectroscopic evidence of two galaxy groups along the blazar's line of sight: one at z ≃ 0.020 and the second one at z ≃ 0.340. The first one is consistent with a known foreground structure, while the second group presented here has six spectroscopically confirmed members. Their location along a red sequence in the colour-magnitude diagram allows us to identify 34 additional candidate members of the more distant group. The blazar's spectrum shows broad absorption features that we identify as arising in the intergalactic medium, thus allowing us to tentatively set a redshift lower limit at z_3C66A ≳ 0.33. As a consequence, we propose that 3C 66A is hosted in a galaxy that belongs to a cluster at z = 0.340.

Author Details

African Journals Online (AJOL)

Tachia, MU. Vol 2, No 2 (2010) - Articles Acute Toxicity of Glyphosate on Clarias Gariepinus Fingerlings Abstract PDF · Vol 4, No 2 (2012) - Articles A survey of ectoparasites of Clarias gariepinus caught from theUniversity of Agriculture Research Fish Farm, Makurdi Abstract PDF. ISSN: 2141-1778. AJOL African Journals ...

The potential for using red claw crayfish and hybrid African catfish as ...

African Journals Online (AJOL)

The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After 15 days, both crayfish and ...

Prevalence of pansteatitis in African sharptooth catfish, Clarias gariepinus (Burchell), in the Kruger National Park, South Africa.

Science.gov (United States)

Huchzermeyer, K David A

2012-11-09

Pansteatitis was confirmed in sharptooth catfish, Clarias gariepinus (Burchell), from three main locations within the Kruger National Park (KNP); the Olifants River Gorge, Engelhard Dam on the Letaba River and from the Sabie River in the Sabiepoort. An increasing prevalence of pansteatitis was observed in catfish during repeated samplings from the Olifants Gorge from 2009 to 2011 and co-existence of old and recent lesions indicated on-going incitement of pansteatitis. Only a low prevalence of pansteatitis was observed in catfish sampled from the Olifants River upstream of the Gorge in the KNP and no pansteatitis was observed in catfish sampled from a rain-filled dam not connected to the Olifants River. Common to both the Olifants Gorge and the Sabiepoort is the damming of the rivers in Mozambique to form lakes Massingir and Corumana respectively. Anthropogenic activities resulting in potential pollution of the rivers differ greatly between these two catchments, providing argument against a primary pollution-related aetiology of the pansteatitis found at these two sites. Compared with other sites, analysis of stomach contents of catfish from the Olifants Gorge and the Sabiepoort strongly suggested that consumption of a predominantly fish diet was associated with the development of pansteatitis in these fish. In a farmed population of catfish used as positive control, development of pansteatitis could be ascribed to consumption of rancid fish waste from a trout slaughterhouse. In the Olifants Gorge, alien invasive silver carp, Hypophthalmychthys molitrix (Valenciennes), seasonally migrate upstream out of Lake Massingir to spawn. This schooling species is an obligate phytoplankton feeder with consequent high levels of adipose tissue n-3 polyunsaturated fatty acids. In the Olifants Gorge, at least, this may explain seasonal exposure to levels of polyunsaturated fats in the diets of catfish and crocodiles to which these animals are not adapted. The possible roles of

Prevalence of pansteatitis in African sharptooth catfish, Clarias gariepinus (Burchell, in the Kruger National Park, South Africa

Directory of Open Access Journals (Sweden)

K. David A. Huchzermeyer

2012-04-01

Full Text Available Pansteatitis was confirmed in sharptooth catfish, Clarias gariepinus (Burchell, from three main locations within the Kruger National Park (KNP; the Olifants River Gorge, Engelhard Dam on the Letaba River and from the Sabie River in the Sabiepoort. An increasing prevalence of pansteatitis was observed in catfish during repeated samplings from the Olifants Gorge from 2009 to 2011 and co-existence of old and recent lesions indicated on-going incitement of pansteatitis. Only a low prevalence of pansteatitis was observed in catfish sampled from the Olifants River upstream of the Gorge in the KNP and no pansteatitis was observed in catfish sampled from a rain-filled dam not connected to the Olifants River. Common to both the Olifants Gorge and the Sabiepoort is the damming of the rivers in Mozambique to form lakes Massingir and Corumana respectively. Anthropogenic activities resulting in potential pollution of the rivers differ greatly between these two catchments, providing argument against a primary pollution-related aetiology of the pansteatitis found at these two sites. Compared with other sites, analysis of stomach contents of catfish from the Olifants Gorge and the Sabiepoort strongly suggested that consumption of a predominantly fish diet was associated with the development of pansteatitis in these fish. In a farmed population of catfish used as positive control, development of pansteatitis could be ascribed to consumption of rancid fish waste from a trout slaughterhouse. In the Olifants Gorge, alien invasive silver carp, Hypophthalmychthys molitrix (Valenciennes, seasonally migrate upstream out of Lake Massingir to spawn. This schooling species is an obligate phytoplankton feeder with consequent high levels of adipose tissue n-3 polyunsaturated fatty acids. In the Olifants Gorge, at least, this may explain seasonal exposure to levels of polyunsaturated fats in the diets of catfish and crocodiles to which these animals are not adapted. The

Prevalence of pansteatitis in African sharptooth catfish, Clarias gariepinus (Burchell, in the Kruger National Park, South Africa

Directory of Open Access Journals (Sweden)

K. David A. Huchzermeyer

2012-11-01

Full Text Available Pansteatitis was confirmed in sharptooth catfish, Clarias gariepinus (Burchell, from three main locations within the Kruger National Park (KNP; the Olifants River Gorge, Engelhard Dam on the Letaba River and from the Sabie River in the Sabiepoort. An increasing prevalence of pansteatitis was observed in catfish during repeated samplings from the Olifants Gorge from 2009 to 2011 and co-existence of old and recent lesions indicated on-going incitement of pansteatitis. Only a low prevalence of pansteatitis was observed in catfish sampled from the Olifants River upstream of the Gorge in the KNP and no pansteatitis was observed in catfish sampled from a rain-filled dam not connected to the Olifants River. Common to both the Olifants Gorge and the Sabiepoort is the damming of the rivers in Mozambique to form lakes Massingir and Corumana respectively. Anthropogenic activities resulting in potential pollution of the rivers differ greatly between these two catchments, providing argument against a primary pollution-related aetiology of the pansteatitis found at these two sites. Compared with other sites, analysis of stomach contents of catfish from the Olifants Gorge and the Sabiepoort strongly suggested that consumption of a predominantly fish diet was associated with the development of pansteatitis in these fish. In a farmed population of catfish used as positive control, development of pansteatitis could be ascribed to consumption of rancid fish waste from a trout slaughterhouse. In the Olifants Gorge, alien invasive silver carp, Hypophthalmychthys molitrix (Valenciennes, seasonally migrate upstream out of Lake Massingir to spawn. This schooling species is an obligate phytoplankton feeder with consequent high levels of adipose tissue n-3 polyunsaturated fatty acids. In the Olifants Gorge, at least, this may explain seasonal exposure to levels of polyunsaturated fats in the diets of catfish and crocodiles to which these animals are not adapted. The

Louisiana SIP: LAC 33:III Ch 2147. Limiting Volatile Organic Compound (VOC) Emissions from Reactor Processes and Distillation Operations in Synthetic Organic Chemical manufacturing Industry (SOCMI); SIP effective 2011-08-04 (LAd34) to 2017-09-27

Science.gov (United States)

Louisiana SIP: LAC 33:III Ch 2147. Limiting Volatile Organic Compound (VOC) Emissions from Reactor Processes and Distillation Operations in Synthetic Organic Chemical manufacturing Industry (SOCMI); SIP effective 2011-08-04 (LAd34) to 2017-09-27

Cloning, localization and differential expression of Neuropeptide-Y during early brain development and gonadal recrudescence in the catfish, Clarias gariepinus.

Science.gov (United States)

Sudhakumari, Cheni-Chery; Anitha, Arumugam; Murugananthkumar, Raju; Tiwari, Dinesh Kumar; Bhasker, Dharavath; Senthilkumaran, Balasubramanian; Dutta-Gupta, Aparna

2017-09-15

Neuropeptide-Y (NPY) has diverse physiological functions which are extensively studied in vertebrates. However, regulatory role of NPY in relation to brain ontogeny and recrudescence with reference to reproduction is less understood in fish. Present report for the first time evaluated the significance of NPY by transient esiRNA silencing and also analyzed its expression during brain development and gonadal recrudescence in the catfish, Clarias gariepinus. As a first step, full-length cDNA of NPY was cloned from adult catfish brain, which shared high homology with its counterparts from other teleosts upon phylogenetic analysis. Tissue distribution revealed dominant expression of NPY in brain and testis. NPY expression increased during brain development wherein the levels were higher in 100 and 150days post hatch females than the respective age-matched males. Seasonal cycle analysis showed high expression of NPY in brain during pre-spawning phase in comparison with other reproductive phases. Localization studies exhibited the presence of NPY, abundantly, in the regions of preoptic area, hypothalamus and pituitary. Transient silencing of NPY-esiRNA directly into the brain significantly decreased NPY expression in both the male and female brain of catfish which further resulted in significant decrease of transcripts of tryptophan hydroxylase 2, catfish gonadotropin-releasing hormone (cfGnRH), tyrosine hydroxylase and 3β-hydroxysteroid dehydrogenase in brain and luteinizing hormone-β/gonadotropin-II (lh-β/GTH-II) in pituitary exhibiting its influence on gonadal axis. In addition, significant decrease of several ovary-related transcripts was observed in NPY-esiRNA silenced female catfish, indicating the plausible role of NPY in ovary through cfGnRH-GTH axis. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of Ku80 deficiency on mutation frequencies and spectra at a LacZ reporter locus in mouse tissues and cells.

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Rita A Busuttil

Full Text Available Non-homologous end joining (NHEJ is thought to be an important mechanism for preventing the adverse effects of DNA double strand breaks (DSBs and its absence has been associated with premature aging. To investigate the effect of inactivated NHEJ on spontaneous mutation frequencies and spectra in vivo and in cultured cells, we crossed a Ku80-deficient mouse with mice harboring a lacZ-plasmid-based mutation reporter. We analyzed various organs and tissues, as well as cultured embryonic fibroblasts, for mutations at the lacZ locus. When comparing mutant with wild-type mice, we observed a significantly higher number of genome rearrangements in liver and spleen and a significantly lower number of point mutations in liver and brain. The reduced point mutation frequency was not due to a decrease in small deletion mutations thought to be a hallmark of NHEJ, but could be a consequence of increased cellular responses to unrepaired DSBs. Indeed, we found a substantial increase in persistent 53BP1 and gammaH2AX DNA damage foci in Ku80-/- as compared to wild-type liver. Treatment of cultured Ku80-deficient or wild-type embryonic fibroblasts, either proliferating or quiescent, with hydrogen peroxide or bleomycin showed no differences in the number or type of induced genome rearrangements. However, after such treatment, Ku80-deficient cells did show an increased number of persistent DNA damage foci. These results indicate that Ku80-dependent repair of DNA damage is predominantly error-free with the effect of alternative more error-prone pathways creating genome rearrangements only detectable after extended periods of time, i.e., in young adult animals. The observed premature aging likely results from a combination of increased cellular senescence and an increased load of stable, genome rearrangements.

Bilan des introductions de salmonidés dans les lacs et ruisseaux d'altitude des Hautes-Pyrénées

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DELACOSTE M.

1997-01-01

Full Text Available Les introductions de Salmonidés ont été importantes au cours des 60 dernières années dans les lacs et ruisseaux d'altitude des Hautes-Pyrénées. Six espèces de Salmonidés ont été introduites dans des milieux qui, pour la plupart, étaient vierges de populations piscicoles : la truite commune (Salmo trutta L., la truite arc-en-ciel (Oncorhynchus mykiss Walbaum, l'omble de fontaine (Salvelinus fontinalis Mitchill, l'omble chevalier (Salvelinus alpinus L., le cristivomer (Salvelinus namaycush Walbaum et le splake (Salvelinus fontinalis x Salvelinus namaycush. Dans de très nombreux cas, ces introductions ont abouti à des acclimatations. En revanche, les naturalisations sont beaucoup plus rares. Seules les espèces lacustres (cristivomer et omble chevalier se sont naturalisées dans la majorité des lacs où elles ont été introduites. Les conditions de reproduction constituent le facteur clé permettant d'expliquer la naturalisation des espèces. En ruisseau, il faut y ajouter la compétition avec l'espèce indigène (la truite commune, la pression halieutique ainsi que les conditions hivernales très rigoureuses. Les incidences écologiques des introductions sur les populations de truites communes indigènes sont faibles. En revanche, elles ne sont pas négligeables pour les populations de batraciens. Cette politique d'introduction a largement participé au développement de l'halieutisme dans ces milieux d'altitude. En cela, les introductions ont parfaitement répondu aux objectifs halieutiques qu'on leur avait fixés. L'acquisition de connaissances sur l'ensemble de la chaîne pyrénéenne constitue aujourd'hui une étape incontournable pour une politique de gestion globale des introductions.